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Gao YN, Wang R, Gu G, Chung R, Olfson M. Inpatient antipsychotic medication switching and rehospitalization risk among patients with schizophrenia-spectrum disorders. Schizophr Res 2024; 267:165-172. [PMID: 38547719 DOI: 10.1016/j.schres.2024.03.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 02/08/2024] [Accepted: 03/18/2024] [Indexed: 04/19/2024]
Abstract
OBJECTIVE To describe patterns of antipsychotic switching among patients hospitalized for schizophrenia and to correlate antipsychotic switching with hospital readmission risk. METHODS We identified 3295 patients with index hospitalizations for schizophrenia or schizoaffective disorder from New York State Medicaid claims 2017-2018 who had filled at least one prescription for an antipsychotic in both the 44 days (one month +14 day grace period) prior to and after their admission. We identified patients who had kept or switched any of their antipsychotic medication between the pre- and post-periods surrounding their index hospitalization. We compared the kept and switched any groups, adjusting for patient characteristics. RESULTS Of patients who had filled antipsychotic prescriptions in both the 44 days prior to and after their hospitalization, 1599 (48.6 %) had switched at least one antipsychotic and 1215 (36.8 %) had switched their primary antipsychotic. Switching any antipsychotic was associated with increased hazards of readmission, HR = 1.21, 95%CI 1.09-1.35, which was slightly concentrated during the first 90 days after hospital discharge. CONCLUSIONS Switching antipsychotic medications during hospitalization occurs commonly and is associated with higher rehospitalization risk following hospital discharge.
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Affiliation(s)
- Y Nina Gao
- Department of Psychiatry, Vagelos College of Physicians & Surgeons Columbia University and New York State Psychiatric Institute, New York, United States of America.
| | - Rui Wang
- New York State Office of Mental Health, Albany, New York, United States of America
| | - Gyojeong Gu
- New York State Office of Mental Health, Albany, New York, United States of America
| | - Rakkoo Chung
- New York State Office of Mental Health, Albany, New York, United States of America
| | - Mark Olfson
- Departments of Psychiatry and Epidemiology, Columbia University, New York and New York State Psychiatric Institute, New York, United States of America
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Patel SR, Messner GR, Radigan M, Sang Y, Wang R, Gu G, Myers RW, Dixon LB, Simpson HB. Retrospective State Medicaid Claims Analysis of Children and Adults With Obsessive-Compulsive Disorder. Psychiatr Serv 2023; 74:1185-1188. [PMID: 37096356 DOI: 10.1176/appi.ps.20220152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/26/2023]
Abstract
OBJECTIVE With a lifetime U.S. prevalence of 2.3%, obsessive-compulsive disorder (OCD) is a chronic condition often producing reduced quality of life and disability when left untreated. Little is known about the prevalence or treatment of diagnosed OCD in public behavioral health systems. METHODS Using a claims analysis of 2019 New York State Medicaid data (N=2,245,084 children; N=4,274,100 adults), the authors investigated the prevalence and characteristics of children and adults with OCD. The authors also examined whether these individuals received treatment with medication or psychotherapy. RESULTS The prevalence of OCD was 0.2% among children and 0.3% among adults. Fewer than half of children (40.0%) and adults (37.5%) received U.S. Food and Drug Administration-approved medications (with or without psychotherapy); another 19.4% of children and 11.0% of adults received 45- or 60-minute psychotherapy alone. CONCLUSIONS These data demonstrate the need for public behavioral health systems to increase their capacity to identify and treat OCD.
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Affiliation(s)
- Sapana R Patel
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York City (Patel, Messner, Dixon, Simpson); Research Foundation for Mental Hygiene, New York State Psychiatric Institute, New York City (Patel, Dixon, Simpson); New York State Office of Mental Health, Albany (Radigan, Sang, Wang, Gu, Myers)
| | - Gabrielle R Messner
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York City (Patel, Messner, Dixon, Simpson); Research Foundation for Mental Hygiene, New York State Psychiatric Institute, New York City (Patel, Dixon, Simpson); New York State Office of Mental Health, Albany (Radigan, Sang, Wang, Gu, Myers)
| | - Marleen Radigan
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York City (Patel, Messner, Dixon, Simpson); Research Foundation for Mental Hygiene, New York State Psychiatric Institute, New York City (Patel, Dixon, Simpson); New York State Office of Mental Health, Albany (Radigan, Sang, Wang, Gu, Myers)
| | - Yi Sang
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York City (Patel, Messner, Dixon, Simpson); Research Foundation for Mental Hygiene, New York State Psychiatric Institute, New York City (Patel, Dixon, Simpson); New York State Office of Mental Health, Albany (Radigan, Sang, Wang, Gu, Myers)
| | - Rui Wang
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York City (Patel, Messner, Dixon, Simpson); Research Foundation for Mental Hygiene, New York State Psychiatric Institute, New York City (Patel, Dixon, Simpson); New York State Office of Mental Health, Albany (Radigan, Sang, Wang, Gu, Myers)
| | - Gyojeong Gu
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York City (Patel, Messner, Dixon, Simpson); Research Foundation for Mental Hygiene, New York State Psychiatric Institute, New York City (Patel, Dixon, Simpson); New York State Office of Mental Health, Albany (Radigan, Sang, Wang, Gu, Myers)
| | - Robert W Myers
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York City (Patel, Messner, Dixon, Simpson); Research Foundation for Mental Hygiene, New York State Psychiatric Institute, New York City (Patel, Dixon, Simpson); New York State Office of Mental Health, Albany (Radigan, Sang, Wang, Gu, Myers)
| | - Lisa B Dixon
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York City (Patel, Messner, Dixon, Simpson); Research Foundation for Mental Hygiene, New York State Psychiatric Institute, New York City (Patel, Dixon, Simpson); New York State Office of Mental Health, Albany (Radigan, Sang, Wang, Gu, Myers)
| | - H Blair Simpson
- Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York City (Patel, Messner, Dixon, Simpson); Research Foundation for Mental Hygiene, New York State Psychiatric Institute, New York City (Patel, Dixon, Simpson); New York State Office of Mental Health, Albany (Radigan, Sang, Wang, Gu, Myers)
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3
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Basaraba CN, Scodes JM, Dambreville R, Radigan M, Dachepally P, Gu G, Wang R, Dixon LB, Wall MM. Prediction Tool for Individual Outcome Trajectories Across the Next Year in First-Episode Psychosis in Coordinated Specialty Care. JAMA Psychiatry 2023; 80:49-56. [PMID: 36322062 PMCID: PMC9631229 DOI: 10.1001/jamapsychiatry.2022.3571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Accepted: 09/12/2022] [Indexed: 11/07/2022]
Abstract
Importance In coordinated specialty care (CSC) settings for people with a first episode of psychosis, the development of reliable, validated individual-level prediction tools for key outcomes may be informative for shared clinician and client decision-making. Objective To develop an individual-level prediction tool using machine-learning methods that predicts a trajectory of education/work status or psychiatric hospitalization outcomes over a client's next year of quarterly follow-up assessments. Additionally, to visualize these predictions in a way that is informative to clinicians and clients. Design, Setting, and Participants Individual-level data were collected for all patients enrolled in the OnTrackNY program at enrollment and at quarterly follow-ups using standardized forms. The OnTrackNY program, a network of CSC sites in New York State, provides person-centered, recovery-oriented, and evidence-based psychosocial and pharmaceutical interventions to individuals aged 16 to 30 years with recent-onset (<2 years) nonaffective psychosis. Although data collection is ongoing, data for this study were collected from October 2013 to December 2018, and the time frame for analysis was July 2020 to May 2021. Data were separated into a training/cross-validation set to perform internally validated model development and a separate holdout test set (~20% of the sample) for external validation. Random probability forest models were developed to predict individual-level trajectories of outcomes. Exposures Forty-three individual-level demographic and clinical features collected at enrollment in OnTrackNY, 25 of which were time-varying and updated at quarterly follow-up assessments, and 13 site-level demographic and economic census variables. Main Outcomes and Measures Individual-level education and/or employment status and psychiatric hospitalization trajectories at quarterly follow-up periods across the first 2 years of CSC. Results The total study sample consists of 1298 individuals aged 16 to 30 years and included 341 women (26.3%), 949 men (73.1%), and 8 (<1%) with another gender. Prediction models performed well for 1-year trajectories of education/work across all validation sets, with areas under the receiver operating characteristic curve (AUCs) ranging from 0.68 (95% CI, 0.63-0.74) to 0.88 (95% CI, 0.81-0.96). Predictive accuracy for psychiatric hospitalization 3 months ahead reached AUC above 0.70; moreover, predictions of future psychiatric hospitalizations at 6 months and beyond were consistently poor, with AUCs below 0.60. Given the good externally validated performance for predicting education/work, a prototype interactive visualization tool displaying individual-level education/work trajectories and related features was developed. Conclusions and Relevance This study suggests that accurate prediction tools can be developed for outcomes in people with first-episode psychosis, which may help inform shared clinician/client decision-making. Future work should study the effectiveness of its deployment, including proper communication to inform shared clinician/client decision-making in the context of a learning health care system. At present, more work is needed to develop better performing prediction models for future psychiatric hospitalizations before any tool is recommended for this outcome.
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Affiliation(s)
- Cale N. Basaraba
- Area Mental Health Data Science, New York State Psychiatric Institute, New York
| | - Jennifer M. Scodes
- Area Mental Health Data Science, New York State Psychiatric Institute, New York
| | - Renald Dambreville
- Area Mental Health Data Science, New York State Psychiatric Institute, New York
| | - Marleen Radigan
- Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany
| | - Pranith Dachepally
- Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany
| | - Gyojeong Gu
- Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany
| | - Rui Wang
- Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany
| | - Lisa B. Dixon
- Division of Behavioral Health Services and Policies, New York State Psychiatric Institute, New York
- Department of Psychiatry, Columbia University and New York State Psychiatric Institute, New York
| | - Melanie M. Wall
- Area Mental Health Data Science, New York State Psychiatric Institute, New York
- Department of Psychiatry, Columbia University and New York State Psychiatric Institute, New York
- Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, New York
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Humensky JL, Nossel I, Bello I, Malinovsky I, Radigan M, Gu G, Wang R, Wall MM, Jones N, Dixon LB. Rates of Inpatient and Emergency Room Use Before and After Discharge Among Medicaid Enrollees in OnTrackNY. Psychiatr Serv 2021; 72:1328-1331. [PMID: 34106739 PMCID: PMC8570971 DOI: 10.1176/appi.ps.202000791] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE This study examined hospital and emergency room (ER) use among Medicaid enrollees before and after discharge from OnTrackNY, a coordinated specialty care program for recent-onset psychosis. METHODS Medicaid claims data were linked to program data. Inpatient hospitalization, inpatient days, and ER visits were assessed in the 6 months prior to OnTrackNY enrollment and 6 months prior to and after discharge. The sample consisted of 138 participants with continuous Medicaid enrollment during the study. RESULTS Inpatient visits significantly declined from the pre-OnTrackNY enrollment period to the predischarge period (β=-1.23, standard error [SE]=0.22, p<0.001), did not significantly change in the first 6 months after discharge (β=0.19, SE=0.26, p=0.48), and remained significantly lower than before OnTrackNY enrollment (β=-1.05, SE=0.20, p<0.001). Similar patterns were observed for inpatient days and ER use. CONCLUSIONS ER and hospital use declined during OnTrackNY participation and did not significantly change in the first 6 months after discharge.
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Affiliation(s)
- Jennifer L Humensky
- Division of Behavioral Health Services and Policy Research (Humensky, Nossel, Bello, Malinovsky, Dixon) and Division of Mental Health Data Science (Wall), New York State Psychiatric Institute, New York City; Department of Psychiatry, Columbia University Irving Medical Center, New York City (Humensky, Nossel, Bello, Malinovsky, Wall, Dixon); Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Wang); Department of Psychiatry and Behavioral Neurosciences, University of South Florida, Tampa (Jones). Benjamin G. Druss, M.D., M.P.H., served as decision editor on the manuscript
| | - Ilana Nossel
- Division of Behavioral Health Services and Policy Research (Humensky, Nossel, Bello, Malinovsky, Dixon) and Division of Mental Health Data Science (Wall), New York State Psychiatric Institute, New York City; Department of Psychiatry, Columbia University Irving Medical Center, New York City (Humensky, Nossel, Bello, Malinovsky, Wall, Dixon); Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Wang); Department of Psychiatry and Behavioral Neurosciences, University of South Florida, Tampa (Jones). Benjamin G. Druss, M.D., M.P.H., served as decision editor on the manuscript
| | - Iruma Bello
- Division of Behavioral Health Services and Policy Research (Humensky, Nossel, Bello, Malinovsky, Dixon) and Division of Mental Health Data Science (Wall), New York State Psychiatric Institute, New York City; Department of Psychiatry, Columbia University Irving Medical Center, New York City (Humensky, Nossel, Bello, Malinovsky, Wall, Dixon); Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Wang); Department of Psychiatry and Behavioral Neurosciences, University of South Florida, Tampa (Jones). Benjamin G. Druss, M.D., M.P.H., served as decision editor on the manuscript
| | - Igor Malinovsky
- Division of Behavioral Health Services and Policy Research (Humensky, Nossel, Bello, Malinovsky, Dixon) and Division of Mental Health Data Science (Wall), New York State Psychiatric Institute, New York City; Department of Psychiatry, Columbia University Irving Medical Center, New York City (Humensky, Nossel, Bello, Malinovsky, Wall, Dixon); Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Wang); Department of Psychiatry and Behavioral Neurosciences, University of South Florida, Tampa (Jones). Benjamin G. Druss, M.D., M.P.H., served as decision editor on the manuscript
| | - Marleen Radigan
- Division of Behavioral Health Services and Policy Research (Humensky, Nossel, Bello, Malinovsky, Dixon) and Division of Mental Health Data Science (Wall), New York State Psychiatric Institute, New York City; Department of Psychiatry, Columbia University Irving Medical Center, New York City (Humensky, Nossel, Bello, Malinovsky, Wall, Dixon); Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Wang); Department of Psychiatry and Behavioral Neurosciences, University of South Florida, Tampa (Jones). Benjamin G. Druss, M.D., M.P.H., served as decision editor on the manuscript
| | - Gyojeong Gu
- Division of Behavioral Health Services and Policy Research (Humensky, Nossel, Bello, Malinovsky, Dixon) and Division of Mental Health Data Science (Wall), New York State Psychiatric Institute, New York City; Department of Psychiatry, Columbia University Irving Medical Center, New York City (Humensky, Nossel, Bello, Malinovsky, Wall, Dixon); Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Wang); Department of Psychiatry and Behavioral Neurosciences, University of South Florida, Tampa (Jones). Benjamin G. Druss, M.D., M.P.H., served as decision editor on the manuscript
| | - Rui Wang
- Division of Behavioral Health Services and Policy Research (Humensky, Nossel, Bello, Malinovsky, Dixon) and Division of Mental Health Data Science (Wall), New York State Psychiatric Institute, New York City; Department of Psychiatry, Columbia University Irving Medical Center, New York City (Humensky, Nossel, Bello, Malinovsky, Wall, Dixon); Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Wang); Department of Psychiatry and Behavioral Neurosciences, University of South Florida, Tampa (Jones). Benjamin G. Druss, M.D., M.P.H., served as decision editor on the manuscript
| | - Melanie M Wall
- Division of Behavioral Health Services and Policy Research (Humensky, Nossel, Bello, Malinovsky, Dixon) and Division of Mental Health Data Science (Wall), New York State Psychiatric Institute, New York City; Department of Psychiatry, Columbia University Irving Medical Center, New York City (Humensky, Nossel, Bello, Malinovsky, Wall, Dixon); Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Wang); Department of Psychiatry and Behavioral Neurosciences, University of South Florida, Tampa (Jones). Benjamin G. Druss, M.D., M.P.H., served as decision editor on the manuscript
| | - Nev Jones
- Division of Behavioral Health Services and Policy Research (Humensky, Nossel, Bello, Malinovsky, Dixon) and Division of Mental Health Data Science (Wall), New York State Psychiatric Institute, New York City; Department of Psychiatry, Columbia University Irving Medical Center, New York City (Humensky, Nossel, Bello, Malinovsky, Wall, Dixon); Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Wang); Department of Psychiatry and Behavioral Neurosciences, University of South Florida, Tampa (Jones). Benjamin G. Druss, M.D., M.P.H., served as decision editor on the manuscript
| | - Lisa B Dixon
- Division of Behavioral Health Services and Policy Research (Humensky, Nossel, Bello, Malinovsky, Dixon) and Division of Mental Health Data Science (Wall), New York State Psychiatric Institute, New York City; Department of Psychiatry, Columbia University Irving Medical Center, New York City (Humensky, Nossel, Bello, Malinovsky, Wall, Dixon); Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Wang); Department of Psychiatry and Behavioral Neurosciences, University of South Florida, Tampa (Jones). Benjamin G. Druss, M.D., M.P.H., served as decision editor on the manuscript
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5
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Li N, Hou R, Zhao LM, Gu G, Hou SY. [Expression of melanoma-associated antigen-C2 in breast cancers and mechanism]. Zhonghua Zhong Liu Za Zhi 2021; 43:821-826. [PMID: 34407585 DOI: 10.3760/cma.j.cn112152-20200116-00043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To analyze the expression pattern, mechanism and clinical significance of melanoma-associated antigen-C2 (MAGE-C2) in tumor-free breast specimens, breast benign disease specimens and breast cancer specimens. Methods: Reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry were used to investigate the expressions of MAGE-C2 in 60 tumor-free breast specimens, 60 breast benign disease specimens and 60 breast cancer specimens. The correlation of MAGE-C2 expression with clinicopathological parameters and prognosis of breast cancer patients were analyzed. The expression of MAGE-C2 was also detected by RT-PCR in breast cancer cell MCF-7 and MDA-MB-231 treated with DNA methylase inhibitor 5-aza-2'-deoxycytidine (5-aza-CdR) and histone deacetylase inhibitor trichostatin A (TSA). Results: The positive expression rates of MAGE-C2 mRNA and protein were 61.7% (37/60) and 58.3% (35/60) in breast cancer specimens, respectively, while negative expressed in breast and begin disease specimens. MAGE-C2 protein expression was associated with tumor grade, histological type and blood vessel invasion of breast cancer patients (P<0.05). The incidence of recurrence-free survival of patients with positive MAGE-C2 expression were lower than that of patients with negative MAGE-C2 expression (P<0.05). Multivariate Cox regression analysis showed that the clinical stage (P<0.01), lymph node metastasis (P<0.05) and MAGE-C2 expression (P<0.05) were the independent prognostic factors of breast cancer patients. The MAGE-C2 mRNA was not observed in the control and TSA treated breast cancer cells while upregulated in the 5-aza-CdR treated cells. Besides, 5-aza-CdR combined with TSA further enhanced MAGE-C2 mRNA level in breast cancer cells (P<0.05). Conclusions: MAGE-C2 is one of the tumor-specific antigen and its expression is related with the poor prognosis of breast cancer patients. DNA methylation and histone acetylation may be an important regulation mechanism of MAGE-C2 gene expression.
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Affiliation(s)
- N Li
- Department of Oncology, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China
| | - R Hou
- Department of Oncology, the Fourth Hospital of Hebei Medical University, Shijiazhuang 050019, China
| | - L M Zhao
- Department of Research Center, the Fourth Hospital of Hebei Medical University, Shijiazhuang 050019, China
| | - G Gu
- Department of Rheumatology and Immunology, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China
| | - S Y Hou
- Department of Rheumatology and Immunology, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China
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6
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Galeski S, Ehmcke T, Wawrzyńczak R, Lozano PM, Cho K, Sharma A, Das S, Küster F, Sessi P, Brando M, Küchler R, Markou A, König M, Swekis P, Felser C, Sassa Y, Li Q, Gu G, Zimmermann MV, Ivashko O, Gorbunov DI, Zherlitsyn S, Förster T, Parkin SSP, Wosnitza J, Meng T, Gooth J. Origin of the quasi-quantized Hall effect in ZrTe 5. Nat Commun 2021; 12:3197. [PMID: 34045452 PMCID: PMC8159947 DOI: 10.1038/s41467-021-23435-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 04/27/2021] [Indexed: 02/04/2023] Open
Abstract
The quantum Hall effect (QHE) is traditionally considered to be a purely two-dimensional (2D) phenomenon. Recently, however, a three-dimensional (3D) version of the QHE was reported in the Dirac semimetal ZrTe5. It was proposed to arise from a magnetic-field-driven Fermi surface instability, transforming the original 3D electron system into a stack of 2D sheets. Here, we report thermodynamic, spectroscopic, thermoelectric and charge transport measurements on such ZrTe5 samples. The measured properties: magnetization, ultrasound propagation, scanning tunneling spectroscopy, and Raman spectroscopy, show no signatures of a Fermi surface instability, consistent with in-field single crystal X-ray diffraction. Instead, a direct comparison of the experimental data with linear response calculations based on an effective 3D Dirac Hamiltonian suggests that the quasi-quantization of the observed Hall response emerges from the interplay of the intrinsic properties of the ZrTe5 electronic structure and its Dirac-type semi-metallic character.
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Affiliation(s)
- S Galeski
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany.
| | - T Ehmcke
- Institute for Theoretical Physics and Würzburg-Dresden Cluster of Excellence ct.qmat, Technische Universität Dresden, Dresden, Germany
| | - R Wawrzyńczak
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - P M Lozano
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - K Cho
- Max Planck Institute of Microstructure Physics, Halle, Saale, Germany
| | - A Sharma
- Max Planck Institute of Microstructure Physics, Halle, Saale, Germany
| | - S Das
- Max Planck Institute of Microstructure Physics, Halle, Saale, Germany
| | - F Küster
- Max Planck Institute of Microstructure Physics, Halle, Saale, Germany
| | - P Sessi
- Max Planck Institute of Microstructure Physics, Halle, Saale, Germany
| | - M Brando
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - R Küchler
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - A Markou
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - M König
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - P Swekis
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - C Felser
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - Y Sassa
- Department of Physics, Chalmers University of Technology, Gothenburg, Sweden
| | - Q Li
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - G Gu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | | | - O Ivashko
- Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany
| | - D I Gorbunov
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat,, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - S Zherlitsyn
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat,, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - T Förster
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat,, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - S S P Parkin
- Max Planck Institute of Microstructure Physics, Halle, Saale, Germany
| | - J Wosnitza
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat,, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, Dresden, Germany
| | - T Meng
- Institute for Theoretical Physics and Würzburg-Dresden Cluster of Excellence ct.qmat, Technische Universität Dresden, Dresden, Germany
| | - J Gooth
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany.
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, Dresden, Germany.
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Luo L, Cheng D, Song B, Wang LL, Vaswani C, Lozano PM, Gu G, Huang C, Kim RHJ, Liu Z, Park JM, Yao Y, Ho K, Perakis IE, Li Q, Wang J. A light-induced phononic symmetry switch and giant dissipationless topological photocurrent in ZrTe 5. Nat Mater 2021; 20:329-334. [PMID: 33462464 DOI: 10.1038/s41563-020-00882-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 11/17/2020] [Indexed: 06/12/2023]
Abstract
Dissipationless currents from topologically protected states are promising for disorder-tolerant electronics and quantum computation. Here, we photogenerate giant anisotropic terahertz nonlinear currents with vanishing scattering, driven by laser-induced coherent phonons of broken inversion symmetry in a centrosymmetric Dirac material ZrTe5. Our work suggests that this phononic terahertz symmetry switching leads to formation of Weyl points, whose chirality manifests in a transverse, helicity-dependent current, orthogonal to the dynamical inversion symmetry breaking axis, via circular photogalvanic effect. The temperature-dependent topological photocurrent exhibits several distinct features: Berry curvature dominance, particle-hole reversal near conical points and chirality protection that is responsible for an exceptional ballistic transport length of ~10 μm. These results, together with first-principles modelling, indicate two pairs of Weyl points dynamically created by B1u phonons of broken inversion symmetry. Such phononic terahertz control breaks ground for coherent manipulation of Weyl nodes and robust quantum transport without application of static electric or magnetic fields.
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Affiliation(s)
- Liang Luo
- Department of Physics and Astronomy, Iowa State University and Ames Laboratory, US Department of Energy, Ames, IA, USA
| | - Di Cheng
- Department of Physics and Astronomy, Iowa State University and Ames Laboratory, US Department of Energy, Ames, IA, USA
| | - Boqun Song
- Department of Physics and Astronomy, Iowa State University and Ames Laboratory, US Department of Energy, Ames, IA, USA
| | - Lin-Lin Wang
- Department of Physics and Astronomy, Iowa State University and Ames Laboratory, US Department of Energy, Ames, IA, USA
| | - Chirag Vaswani
- Department of Physics and Astronomy, Iowa State University and Ames Laboratory, US Department of Energy, Ames, IA, USA
| | - P M Lozano
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY, USA
| | - G Gu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - Chuankun Huang
- Department of Physics and Astronomy, Iowa State University and Ames Laboratory, US Department of Energy, Ames, IA, USA
| | - Richard H J Kim
- Department of Physics and Astronomy, Iowa State University and Ames Laboratory, US Department of Energy, Ames, IA, USA
| | - Zhaoyu Liu
- Department of Physics and Astronomy, Iowa State University and Ames Laboratory, US Department of Energy, Ames, IA, USA
| | - Joong-Mok Park
- Department of Physics and Astronomy, Iowa State University and Ames Laboratory, US Department of Energy, Ames, IA, USA
| | - Yongxin Yao
- Department of Physics and Astronomy, Iowa State University and Ames Laboratory, US Department of Energy, Ames, IA, USA
| | - Kaiming Ho
- Department of Physics and Astronomy, Iowa State University and Ames Laboratory, US Department of Energy, Ames, IA, USA
| | - Ilias E Perakis
- Department of Physics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Qiang Li
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA.
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY, USA.
| | - Jigang Wang
- Department of Physics and Astronomy, Iowa State University and Ames Laboratory, US Department of Energy, Ames, IA, USA.
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8
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Galeski S, Zhao X, Wawrzyńczak R, Meng T, Förster T, Lozano PM, Honnali S, Lamba N, Ehmcke T, Markou A, Li Q, Gu G, Zhu W, Wosnitza J, Felser C, Chen GF, Gooth J. Unconventional Hall response in the quantum limit of HfTe 5. Nat Commun 2020; 11:5926. [PMID: 33230118 PMCID: PMC7683529 DOI: 10.1038/s41467-020-19773-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 10/21/2020] [Indexed: 11/18/2022] Open
Abstract
Interacting electrons confined to their lowest Landau level in a high magnetic field can form a variety of correlated states, some of which manifest themselves in a Hall effect. Although such states have been predicted to occur in three-dimensional semimetals, a corresponding Hall response has not yet been experimentally observed. Here, we report the observation of an unconventional Hall response in the quantum limit of the bulk semimetal HfTe5, adjacent to the three-dimensional quantum Hall effect of a single electron band at low magnetic fields. The additional plateau-like feature in the Hall conductivity of the lowest Landau level is accompanied by a Shubnikov-de Haas minimum in the longitudinal electrical resistivity and its magnitude relates as 3/5 to the height of the last plateau of the three-dimensional quantum Hall effect. Our findings are consistent with strong electron-electron interactions, stabilizing an unconventional variant of the Hall effect in a three-dimensional material in the quantum limit.
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Affiliation(s)
- S Galeski
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany.
| | - X Zhao
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, 100190, Beijing, China
- Songshan Lake Materials Laboratory, 523808, Dongguan, Guangdong, China
- School of Physics Science, University of Chinese Academy of Sciences, 100049, Beijing, China
| | - R Wawrzyńczak
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - T Meng
- Institute of Theoretical Physics and Würzburg-Dresden Cluster of Excellence ct.qmat, Technische Universität Dresden, 01062, Dresden, Germany
| | - T Förster
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - P M Lozano
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY, 11794-3800, USA
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - S Honnali
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - N Lamba
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - T Ehmcke
- Institute of Theoretical Physics and Würzburg-Dresden Cluster of Excellence ct.qmat, Technische Universität Dresden, 01062, Dresden, Germany
| | - A Markou
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - Q Li
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY, 11794-3800, USA
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - G Gu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - W Zhu
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physics Science, University of Chinese Academy of Sciences, 100049, Beijing, China
| | - J Wosnitza
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany
| | - C Felser
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - G F Chen
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, 100190, Beijing, China
- Songshan Lake Materials Laboratory, 523808, Dongguan, Guangdong, China
- School of Physics Science, University of Chinese Academy of Sciences, 100049, Beijing, China
| | - J Gooth
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany.
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany.
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9
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Reber TJ, Zhou X, Plumb NC, Parham S, Waugh JA, Cao Y, Sun Z, Li H, Wang Q, Wen JS, Xu ZJ, Gu G, Yoshida Y, Eisaki H, Arnold GB, Dessau DS. A unified form of low-energy nodal electronic interactions in hole-doped cuprate superconductors. Nat Commun 2019; 10:5737. [PMID: 31844065 PMCID: PMC6914777 DOI: 10.1038/s41467-019-13497-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 11/08/2019] [Indexed: 11/13/2022] Open
Abstract
Using angle resolved photoemission spectroscopy measurements of Bi2Sr2CaCu2O8+δ over a wide range of doping levels, we present a universal form for the non-Fermi liquid electronic interactions in the nodal direction in the exotic normal state phase. It is described by a continuously varying power law exponent versus energy and temperature (hence named a Power Law Liquid or PLL), which with doping varies smoothly from a quadratic Fermi Liquid in the overdoped regime, to a linear Marginal Fermi Liquid at optimal doping, to a non-quasiparticle non-Fermi Liquid in the underdoped regime. The coupling strength is essentially constant across all regimes and is consistent with Planckian dissipation. Using the extracted PLL parameters we reproduce the experimental optics and resistivity over a wide range of doping and normal-state temperature values, including the T* pseudogap temperature scale observed in the resistivity curves. This breaks the direct link to the pseudogapping of antinodal spectral weight observed at similar temperature scales and gives an alternative direction for searches of the microscopic mechanism. The normal state of hole-doped, high-temperature superconductors is a currently-unexplained "strange metal" with exotic electronic behaviour. Here, the authors show that a doping-dependent power law ansatz for the electronic scattering phenomenologically captures ARPES, transport and optics observations.
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Affiliation(s)
- T J Reber
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA. .,Department of Chemistry, University of Georgia, Athens, GA, 30602, USA.
| | - X Zhou
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA.
| | - N C Plumb
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA.,Swiss Light Source, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - S Parham
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA
| | - J A Waugh
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA
| | - Y Cao
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA
| | - Z Sun
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA.,University of Science and Technology of China, Hefei, China
| | - H Li
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA
| | - Q Wang
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA
| | - J S Wen
- Condensed Matter Physics and Materials Science Department, Brookhaven National Labs, Upton, NY, 11973, USA
| | - Z J Xu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Labs, Upton, NY, 11973, USA
| | - G Gu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Labs, Upton, NY, 11973, USA
| | - Y Yoshida
- AIST Tsukuba Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki, 3058568, Japan
| | - H Eisaki
- AIST Tsukuba Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki, 3058568, Japan
| | - G B Arnold
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA
| | - D S Dessau
- Department of Physics, University of Colorado, Boulder, CO, 80309-0390, USA. .,Center for Experiments on Quantum Materials, University of Colorado, Boulder, CO, 80309-0390, USA.
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10
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Yin H, Gu G, Nou X, Patel J. Comparative evaluation of irrigation waters on microbiological safety of spinach in field. J Appl Microbiol 2019; 127:1889-1900. [DOI: 10.1111/jam.14436] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 08/09/2019] [Accepted: 08/22/2019] [Indexed: 01/22/2023]
Affiliation(s)
- H.‐B. Yin
- Environmental Microbial and Food Safety Laboratory USDA ARS Beltsville MD USA
| | - G. Gu
- Environmental Microbial and Food Safety Laboratory USDA ARS Beltsville MD USA
| | - X. Nou
- Environmental Microbial and Food Safety Laboratory USDA ARS Beltsville MD USA
| | - J. Patel
- Environmental Microbial and Food Safety Laboratory USDA ARS Beltsville MD USA
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11
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Radigan M, Gu G, Frimpong EY, Wang R, Huz S, Li M, Nossel I, Dixon L. A New Method for Estimating Incidence of First Psychotic Diagnosis in a Medicaid Population. Psychiatr Serv 2019; 70:665-673. [PMID: 31138057 DOI: 10.1176/appi.ps.201900033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Early intervention programs for first-episode psychosis (FEP) require population-based methods to identify individuals with FEP. This study adapted a previously published method to estimate incidence of first psychotic diagnosis in a state Medicaid program. Secondary aims were to examine demographic and service patterns associated with a first psychotic diagnosis in Medicaid. METHODS A retrospective, population-based study of New York State Medicaid data was conducted to identify first occurrence of psychotic diagnosis among persons ages 15-35 between January 1, 2013, and December 31, 2017 (N=31,606). Age-stratified incidence rates (IRs) were calculated by demographic characteristics, first-diagnosis type, and service-related characteristics. Review of charts from OnTrackNY and Medicaid managed care organizations (MCOs) was conducted to confirm identified cases. Initial IRs and confirmation rates were used to estimate adjusted IRs. RESULTS Age-stratified IRs varied by demographic, diagnostic, and service-related characteristic. IRs of FEP were higher for persons ages 15 to 25 relative to persons ages 26-35 if the first provider was an acute behavioral health emergency or inpatient setting (rate ratio=1.286; 95% confidence interval=1.24-1.33). Case confirmation rates were 90% for OnTrack NY and 53% for the MCOs. Adjusted annual IR of first diagnosis of psychosis was 272 per 100,000. CONCLUSIONS Incidence of first psychotic diagnosis in this Medicaid population was higher than previously found in insured populations. Future work will focus on algorithm refinements and piloting outreach. Administrative data algorithms may be useful to providers, Medicaid MCOs, and state Medicaid authorities to support case finding and early intervention.
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Affiliation(s)
- Marleen Radigan
- Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Frimpong, Wang, Huz, Li); New York State Psychiatric Institute and Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York (Nossel, Dixon)
| | - Gyojeong Gu
- Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Frimpong, Wang, Huz, Li); New York State Psychiatric Institute and Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York (Nossel, Dixon)
| | - Eric Y Frimpong
- Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Frimpong, Wang, Huz, Li); New York State Psychiatric Institute and Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York (Nossel, Dixon)
| | - Rui Wang
- Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Frimpong, Wang, Huz, Li); New York State Psychiatric Institute and Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York (Nossel, Dixon)
| | - Steven Huz
- Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Frimpong, Wang, Huz, Li); New York State Psychiatric Institute and Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York (Nossel, Dixon)
| | - Mengxuan Li
- Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Frimpong, Wang, Huz, Li); New York State Psychiatric Institute and Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York (Nossel, Dixon)
| | - Ilana Nossel
- Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Frimpong, Wang, Huz, Li); New York State Psychiatric Institute and Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York (Nossel, Dixon)
| | - Lisa Dixon
- Office of Performance Measurement and Evaluation, New York State Office of Mental Health, Albany (Radigan, Gu, Frimpong, Wang, Huz, Li); New York State Psychiatric Institute and Department of Psychiatry, Columbia University Vagelos College of Physicians and Surgeons, New York (Nossel, Dixon)
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12
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Zhou X, Wang R, Zhang T, Liu F, Zhang W, Wang G, Gu G, Han Q, Xu D, Yao C, Guo D, Fu W, Qi Y, Wang L. Identification of Lysophosphatidylcholines and Sphingolipids as Potential Biomarkers for Acute Aortic Dissection via Serum Metabolomics. J Vasc Surg 2019. [DOI: 10.1016/j.jvs.2019.03.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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13
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Williams J, Tu S, Lodhia C, Gu G, Haar G, O'Connor J, Niewiadomski O, Tandiari T, Nicoll A. Parenteral nutrition: How do patients initiated in the intensive care unit differ from those on the ward? Clinical Nutrition Experimental 2019. [DOI: 10.1016/j.yclnex.2019.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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14
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Kim JA, Dustin D, Gu G, Corona-Rodriguez A, Edwards D, Coarfa C, Keyomarsi K, Fuqua SA. Abstract PD7-11: Therapeutic strategy for ESR1 mutation driven-endocrine resistance in ER-positive breast cancers. Cancer Res 2019. [DOI: 10.1158/1538-7445.sabcs18-pd7-11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Endocrine therapy is used in estrogen receptor (ER)-positive breast cancers, however, 25% of these patients are at risk of distant relapse and the development of acquired endocrine resistance. Recently mutations in the ER gene (ESR1) have been validated to be acquired during the development of endocrine resistance. The most frequent ESR1 mutation, Y537S, promotes ligand-independent ER activity and emerges subclonally during aromatase inhibitor treatment. In this study, we examined the effects of the Y537S ESR1 mutation on cell cycle signaling and therapeutic response to a novel checkpoint inhibitor.
Material and Methods: MCF-7 cells expressing the Y537S ESR1 mutation were generated by CRISPR-Cas9 knock-in techniques. Cells were incubated in steroid deprived conditions. Cell cycle analysis and apoptosis were examined by flow cytometry annnexin-V assays. Proliferation was analyzed by BrdU incorporation. Cell cycle checkpoint kinases were examined by western blot analysis. Cell growth was analyzed using soft agar and MTT assays. Replication stress was identified by RPA32 and gamma-H2AX foci formation assay. For in vivo studies, MCF-7 ESR1 Y537S mutant cells were injected into female athymic nude mice with 17β-estradiol (E2) supplemented water. When tumors reached 350 mm3, tamoxifen (20 mg/kg; s.c.; three times a week), fulvestrant (200 mg/kg; s.c; once a week) and/or PF477736 Chk1 inhibitor (7.5 mg/kg; i.p.; twice a day and twice a week) was treated without E2.
Results: ESR1 Y537S mutant cells accumulated approximately 5 fold in S phase and 1.7 fold in G2/M phase compared to control cells in estrogen-deprived (ED) conditions. BrdU incorporation also increased about 2.5-fold, however, apoptosis was decreased about 60 % compared with wild-type ER parental cells. ESR1 Y537S mutant cells induced significant replication stress, showing increased RPA32 foci together with increased gamma H2AX foci, a marker of DNA double-stranded breaks. ChIP-seq analysis revealed binding sites on ATR and CHEK1 genomic locations. ATR/Chk1-mediated checkpoint signaling was activated in ESR1 Y537S mutant cells, and was repressed with fulvestrant, tamoxifen, or ESR1 siRNA treatment. The Chk1 inhibitor, PF477736, sensitized MCF-7 expressing the ESR1 Y537S mutation to endocrine treatments such as fulvestrant, tamoxifen, and the ER degrader AZD9496 in cell proliferation assays. In MCF-7 ESR1 Y537S mutant xenograft and patient derived mouse models, tamoxifen treatment combined with the Chk1 inhibitor PF477736 repressed primary xenograft tumor doubling times (P=0.038, Wilcoxon test). Treatment of mutant tumors with PF477736 together with fulvestrant significantly inhibited the frequency of distant lung metastases by 80% (P=0.0031, t-test), suggesting that these combinations may be useful in second line treatment of metastatic breast cancer patients resistant to endocrine therapies.
Conclusion: These preclinical results suggest that ESR1 mutant tumors have a therapeutic vulnerability to combination endocrine therapy with cell cycle checkpoint kinase inhibitors. These data demonstrate that this new therapeutic approach may be useful to restore endocrine sensitivity in metastatic breast cancer patients with ESR1 mutation driven-endocrine resistance.
Citation Format: Kim J-A, Dustin D, Gu G, Corona-Rodriguez A, Edwards D, Coarfa C, Keyomarsi K, Fuqua SA. Therapeutic strategy for ESR1 mutation driven-endocrine resistance in ER-positive breast cancers [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD7-11.
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Affiliation(s)
- J-A Kim
- Baylor College of Medicine, Houston, TX; M.D. Anderson Cancer Center, Houston, TX
| | - D Dustin
- Baylor College of Medicine, Houston, TX; M.D. Anderson Cancer Center, Houston, TX
| | - G Gu
- Baylor College of Medicine, Houston, TX; M.D. Anderson Cancer Center, Houston, TX
| | - A Corona-Rodriguez
- Baylor College of Medicine, Houston, TX; M.D. Anderson Cancer Center, Houston, TX
| | - D Edwards
- Baylor College of Medicine, Houston, TX; M.D. Anderson Cancer Center, Houston, TX
| | - C Coarfa
- Baylor College of Medicine, Houston, TX; M.D. Anderson Cancer Center, Houston, TX
| | - K Keyomarsi
- Baylor College of Medicine, Houston, TX; M.D. Anderson Cancer Center, Houston, TX
| | - SA Fuqua
- Baylor College of Medicine, Houston, TX; M.D. Anderson Cancer Center, Houston, TX
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15
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Joo SH, Kim JJ, Yoo JH, Park MS, Lee KS, Gu G, Lee J. Cooper Pair Density of Bi 2Sr 2CaCu 2O 8+ x in Atomic scale at 4.2 K. Nano Lett 2019; 19:1112-1117. [PMID: 30698977 DOI: 10.1021/acs.nanolett.8b04415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In pursuit of the elusive mechanism of high- T C superconductors (HTSC), spectroscopic imaging scanning tunneling microscopy (SI-STM) is an indispensable tool for surveying local properties of HTSC. Since a conventional STM utilizes metal tips, which allow the examination of only quasiparticles and not superconducting (SC) pairs, Josephson tunneling using STM has been demonstrated by many authors in the past. An atomically resolved scanning Josephson tunneling microscopy (SJTM), however, was realized only recently on Bi2Sr2CaCu2O8+ x (Bi-2212) below 50 mK and on the Pb(110) surface at 20 mK. Here we report the atomically resolved SJTM on Bi2Sr2CaCu2O8+ x at 4.2 K using Bi-2212 tips created in situ. The I- V characteristics show clear zero bias conductance peaks following Ambegaokar-Baratoff (AB) theory. A gap map was produced for the first time using an atomically resolved Josephson critical current map I C( r) and AB theory. Surprisingly, we found that this new gap map is anticorrelated to the gap map produced by a conventional method relying on the coherence peaks. Quasiparticle resonance due to a single isolated zinc atom impurity was also observed by SJTM, indicating that atomically resolved SJTM was achieved at 4.2 K. Our result provides a starting point for realizing SJTM at even higher temperatures, rendering possible investigation of the existence of SC pairs in HTSC above the T C.
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Affiliation(s)
- S H Joo
- Department of Physics and Astronomy , Seoul National University (SNU) , Seoul 08826 , Republic of Korea
- Center for Correlated Electron Systems , Institute for Basic Science (IBS) , Seoul 08826 , Republic of Korea
| | - J-J Kim
- Department of Physics and Astronomy , Seoul National University (SNU) , Seoul 08826 , Republic of Korea
- Center for Correlated Electron Systems , Institute for Basic Science (IBS) , Seoul 08826 , Republic of Korea
| | - J H Yoo
- Department of Physics and Astronomy , Seoul National University (SNU) , Seoul 08826 , Republic of Korea
- Center for Correlated Electron Systems , Institute for Basic Science (IBS) , Seoul 08826 , Republic of Korea
| | - M S Park
- Department of Physics and Astronomy , Seoul National University (SNU) , Seoul 08826 , Republic of Korea
- Center for Correlated Electron Systems , Institute for Basic Science (IBS) , Seoul 08826 , Republic of Korea
| | - K S Lee
- Department of Physics and Astronomy , Seoul National University (SNU) , Seoul 08826 , Republic of Korea
- Center for Correlated Electron Systems , Institute for Basic Science (IBS) , Seoul 08826 , Republic of Korea
| | - G Gu
- CMPMS Department , Brookhaven National Laboratory , Upton , New York 11973 , United States
| | - Jinho Lee
- Department of Physics and Astronomy , Seoul National University (SNU) , Seoul 08826 , Republic of Korea
- Center for Correlated Electron Systems , Institute for Basic Science (IBS) , Seoul 08826 , Republic of Korea
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16
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Nossel I, Wall MM, Scodes J, Marino LA, Zilkha S, Bello I, Malinovsky I, Lee R, Radigan M, Smith TE, Sederer L, Gu G, Dixon L. Results of a Coordinated Specialty Care Program for Early Psychosis and Predictors of Outcomes. Psychiatr Serv 2018; 69:863-870. [PMID: 29759055 DOI: 10.1176/appi.ps.201700436] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE This study prospectively evaluated outcomes of OnTrackNY, a statewide coordinated specialty care (CSC) program for treatment of early psychosis in community settings, as well as predictors of outcomes. METHODS The sample included 325 individuals ages 16-30 with recent-onset nonaffective psychosis who were enrolled in OnTrackNY and who had at least one three-month follow-up. Clinicians provided data at baseline and quarterly up to one year. Domains assessed included demographic and clinical characteristics, social and occupational functioning, medications, suicidality and violence, hospitalization, and time to intervention. Primary outcomes included the symptoms, occupational functioning, and social functioning scales of the Global Assessment of Functioning (GAF), as adapted by the U.S. Department of Veterans Affairs Mental Illness Research, Education and Clinical Center; education and employment status; and psychiatric hospitalization rate. RESULTS Education and employment rates increased from 40% to 80% by six months, hospitalization rates decreased from 70% to 10% by three months, and improvement in GAF scores continued for 12 months. Female gender, non-Hispanic white race-ethnicity, and more education at baseline predicted better education and employment status at follow-up. CONCLUSIONS Individuals with early psychosis receiving CSC achieved significant improvements in education and employment and experienced a decrease in hospitalization rate. Demographic variables and baseline education predicted education and employment outcomes. CSC teams should make particular effort to support the occupational goals of individuals at increased risk of not engaging in work or school, including male participants and participants from racial and ethnic minority groups.
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Affiliation(s)
- Ilana Nossel
- Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Marino, Dr. Zilkha, Dr. Bello, Dr. Malinovsky, and Dr. Dixon are with the New York State Psychiatric Institute, New York. Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Bello, Dr. Malinovsky, Dr. Smith, and Dr. Dixon are also with the Department of Psychiatry, Columbia University Medical Center, New York. Dr. Smith is also with the New York State Office of Mental Health, Albany, where Dr. Radigan, Dr. Sederer, and Mr. Gu are affiliated. Dr. Lee is with the Silberman School of Social Work, Hunter College, New York
| | - Melanie M Wall
- Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Marino, Dr. Zilkha, Dr. Bello, Dr. Malinovsky, and Dr. Dixon are with the New York State Psychiatric Institute, New York. Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Bello, Dr. Malinovsky, Dr. Smith, and Dr. Dixon are also with the Department of Psychiatry, Columbia University Medical Center, New York. Dr. Smith is also with the New York State Office of Mental Health, Albany, where Dr. Radigan, Dr. Sederer, and Mr. Gu are affiliated. Dr. Lee is with the Silberman School of Social Work, Hunter College, New York
| | - Jennifer Scodes
- Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Marino, Dr. Zilkha, Dr. Bello, Dr. Malinovsky, and Dr. Dixon are with the New York State Psychiatric Institute, New York. Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Bello, Dr. Malinovsky, Dr. Smith, and Dr. Dixon are also with the Department of Psychiatry, Columbia University Medical Center, New York. Dr. Smith is also with the New York State Office of Mental Health, Albany, where Dr. Radigan, Dr. Sederer, and Mr. Gu are affiliated. Dr. Lee is with the Silberman School of Social Work, Hunter College, New York
| | - Leslie A Marino
- Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Marino, Dr. Zilkha, Dr. Bello, Dr. Malinovsky, and Dr. Dixon are with the New York State Psychiatric Institute, New York. Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Bello, Dr. Malinovsky, Dr. Smith, and Dr. Dixon are also with the Department of Psychiatry, Columbia University Medical Center, New York. Dr. Smith is also with the New York State Office of Mental Health, Albany, where Dr. Radigan, Dr. Sederer, and Mr. Gu are affiliated. Dr. Lee is with the Silberman School of Social Work, Hunter College, New York
| | - Sacha Zilkha
- Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Marino, Dr. Zilkha, Dr. Bello, Dr. Malinovsky, and Dr. Dixon are with the New York State Psychiatric Institute, New York. Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Bello, Dr. Malinovsky, Dr. Smith, and Dr. Dixon are also with the Department of Psychiatry, Columbia University Medical Center, New York. Dr. Smith is also with the New York State Office of Mental Health, Albany, where Dr. Radigan, Dr. Sederer, and Mr. Gu are affiliated. Dr. Lee is with the Silberman School of Social Work, Hunter College, New York
| | - Iruma Bello
- Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Marino, Dr. Zilkha, Dr. Bello, Dr. Malinovsky, and Dr. Dixon are with the New York State Psychiatric Institute, New York. Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Bello, Dr. Malinovsky, Dr. Smith, and Dr. Dixon are also with the Department of Psychiatry, Columbia University Medical Center, New York. Dr. Smith is also with the New York State Office of Mental Health, Albany, where Dr. Radigan, Dr. Sederer, and Mr. Gu are affiliated. Dr. Lee is with the Silberman School of Social Work, Hunter College, New York
| | - Igor Malinovsky
- Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Marino, Dr. Zilkha, Dr. Bello, Dr. Malinovsky, and Dr. Dixon are with the New York State Psychiatric Institute, New York. Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Bello, Dr. Malinovsky, Dr. Smith, and Dr. Dixon are also with the Department of Psychiatry, Columbia University Medical Center, New York. Dr. Smith is also with the New York State Office of Mental Health, Albany, where Dr. Radigan, Dr. Sederer, and Mr. Gu are affiliated. Dr. Lee is with the Silberman School of Social Work, Hunter College, New York
| | - Rufina Lee
- Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Marino, Dr. Zilkha, Dr. Bello, Dr. Malinovsky, and Dr. Dixon are with the New York State Psychiatric Institute, New York. Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Bello, Dr. Malinovsky, Dr. Smith, and Dr. Dixon are also with the Department of Psychiatry, Columbia University Medical Center, New York. Dr. Smith is also with the New York State Office of Mental Health, Albany, where Dr. Radigan, Dr. Sederer, and Mr. Gu are affiliated. Dr. Lee is with the Silberman School of Social Work, Hunter College, New York
| | - Marleen Radigan
- Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Marino, Dr. Zilkha, Dr. Bello, Dr. Malinovsky, and Dr. Dixon are with the New York State Psychiatric Institute, New York. Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Bello, Dr. Malinovsky, Dr. Smith, and Dr. Dixon are also with the Department of Psychiatry, Columbia University Medical Center, New York. Dr. Smith is also with the New York State Office of Mental Health, Albany, where Dr. Radigan, Dr. Sederer, and Mr. Gu are affiliated. Dr. Lee is with the Silberman School of Social Work, Hunter College, New York
| | - Thomas E Smith
- Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Marino, Dr. Zilkha, Dr. Bello, Dr. Malinovsky, and Dr. Dixon are with the New York State Psychiatric Institute, New York. Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Bello, Dr. Malinovsky, Dr. Smith, and Dr. Dixon are also with the Department of Psychiatry, Columbia University Medical Center, New York. Dr. Smith is also with the New York State Office of Mental Health, Albany, where Dr. Radigan, Dr. Sederer, and Mr. Gu are affiliated. Dr. Lee is with the Silberman School of Social Work, Hunter College, New York
| | - Lloyd Sederer
- Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Marino, Dr. Zilkha, Dr. Bello, Dr. Malinovsky, and Dr. Dixon are with the New York State Psychiatric Institute, New York. Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Bello, Dr. Malinovsky, Dr. Smith, and Dr. Dixon are also with the Department of Psychiatry, Columbia University Medical Center, New York. Dr. Smith is also with the New York State Office of Mental Health, Albany, where Dr. Radigan, Dr. Sederer, and Mr. Gu are affiliated. Dr. Lee is with the Silberman School of Social Work, Hunter College, New York
| | - Gyojeong Gu
- Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Marino, Dr. Zilkha, Dr. Bello, Dr. Malinovsky, and Dr. Dixon are with the New York State Psychiatric Institute, New York. Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Bello, Dr. Malinovsky, Dr. Smith, and Dr. Dixon are also with the Department of Psychiatry, Columbia University Medical Center, New York. Dr. Smith is also with the New York State Office of Mental Health, Albany, where Dr. Radigan, Dr. Sederer, and Mr. Gu are affiliated. Dr. Lee is with the Silberman School of Social Work, Hunter College, New York
| | - Lisa Dixon
- Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Marino, Dr. Zilkha, Dr. Bello, Dr. Malinovsky, and Dr. Dixon are with the New York State Psychiatric Institute, New York. Dr. Nossel, Dr. Wall, Ms. Scodes, Dr. Bello, Dr. Malinovsky, Dr. Smith, and Dr. Dixon are also with the Department of Psychiatry, Columbia University Medical Center, New York. Dr. Smith is also with the New York State Office of Mental Health, Albany, where Dr. Radigan, Dr. Sederer, and Mr. Gu are affiliated. Dr. Lee is with the Silberman School of Social Work, Hunter College, New York
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Gelsomino L, Panza S, Giordano C, Barone I, Gu G, Spina E, Catalano S, Fuqua S, Andò S. Mutations in the estrogen receptor alpha hormone binding domain promote stem cell phenotype through notch activation in breast cancer cell lines. Cancer Lett 2018; 428:12-20. [DOI: 10.1016/j.canlet.2018.04.023] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 04/17/2018] [Accepted: 04/19/2018] [Indexed: 12/21/2022]
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Yin HB, Nou X, Gu G, Patel J. Microbiological quality of spinach irrigated with reclaimed wastewater and roof-harvest water. J Appl Microbiol 2018; 125:133-141. [PMID: 29478274 DOI: 10.1111/jam.13746] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 02/09/2018] [Accepted: 02/16/2018] [Indexed: 11/28/2022]
Abstract
AIMS The effect of reclaimed wastewater (RCW) and roof-harvest rainwater (RHW) on the microbiological quality of irrigated spinach was investigated. METHODS AND RESULTS Spinach grown in the controlled environment chamber was irrigated by RCW, RHW or creek water (CW; control water) for 4 weeks, and then six replicate spinach samples from each treatment were collected weekly at 0 h and 24 h postirrigation. Spinach samples were analysed for populations of faecal bacterial indicators and pathogens. Bacterial populations in alternative irrigation water samples were determined by the membrane filtration technique. The RCW samples contained the highest faecal bacterial indicator populations, followed by the CW and RHW throughout the entire study. Irrigation waters containing higher populations of total and faecal coliforms did not necessarily result in higher populations of these bacteria on the irrigated spinach. Higher numbers of E. coli-positive spinach samples were reported from RCW-irrigated spinach, especially with repeated irrigation. Pathogens were not detected from any water or spinach samples. CONCLUSIONS Spinach irrigated with RHW did not significantly affect the populations of faecal indicator bacteria when compared with CW-irrigated spinach. Repeat irrigation with RCW is not recommended due to the increased contamination of E. coli on spinach leaves. SIGNIFICANCE AND IMPACT OF THE STUDY RHW may potentially be used as alternative irrigation water without deleteriously affecting the microbiological safety of the spinach.
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Affiliation(s)
- H-B Yin
- Department of Nutrition and Food Science, University of Maryland, College Park, MD, USA
| | - X Nou
- United States Department of Agriculture, Environmental Microbial and Food Safety Laboratory, Agricultural Research Service, Beltsville, MD, USA
| | - G Gu
- Virginia Tech, Eastern Shore Agricultural Research and Extension Center, Painter, VA, USA
| | - J Patel
- United States Department of Agriculture, Environmental Microbial and Food Safety Laboratory, Agricultural Research Service, Beltsville, MD, USA
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Gu G, Piyarathna B, Coarfa C, Ellis L, Ando' S, Fuqua S. Abstract P1-02-03: The Y537S ESR1 mutation carries unique metabolomics profiling in breast cancer. Cancer Res 2018. [DOI: 10.1158/1538-7445.sabcs17-p1-02-03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background:
Estrogen receptor (ESR1) mutations occur at a high frequency in metastatic breast tumors in patients treated with hormonal therapy in the metastatic setting. We do not know if these mutations changed metabolomics and whether these metabolomics change could affect metastasis.
Experimental design and methods:
We generated ESR1 Y537S homozygous mutations using CRISPR Casp-9 technology. Globe metabolites screening was performed using 6550 Agilent QTOF instrument. Athymic mice were used in tumor xenograft studies. Affymetrix microarrays were performed to compare gene expression changes in Y537S mutant compared with parental cells. Enriched metabolite pathways and gene expression integrated analysis was analyzed by using online analysis tool http://www.metaboanalyst.ca.
Results:
We generated CRISPR ESR1 Y537S mutation homozygous knock-in clones in MCF-7 cells. In vivo experiments revealed that mutant cells are dominant drivers of metastasis. Transcriptome profiling revealed elevated expression of Hallmark pathways, including EMT and estrogen-regulated gene expression. We performed globe metabolites screening using MCF-7 Y537S and MCF-7 parental and identified 134 metabolites. Serum starvation media was used and estrogen was used as control for both cell lines. As we expected estrogen treatment induced metabolites changes in parental cells. However, metabolites in mutant cells were not changed significantly under estrogen treatment. Interestingly, metabolites in the mutant cells at baseline were remarkably upregulated (78 out of 134 identified total metabolites) indicating mutant cells in serum starvation condition had significantly different metabolomics compared with parental cells. Top upregulated pathways include protein biosynthesis, betaine metabolism and ammonia recycling. Integration of microarray gene expression and metabolites reviewed several metabolomics pathways significantly changed in mutant compared with parental cells including for example aminoacyl-tRNA biosynthesis, arginine and proline metabolism and alanine, aspartate and glutamate metabolism.
Conclusion: The Y537S ER mutation is a driver of distant metastasis in ER-positive breast cancer cells. Y537S ER mutant had globe changes of metabolites expression which was confirmed by integrated analysis combining microarray gene expression. The roles of these metabolites need to be studied to correlate with metastasis. Enzymes responsible for converting these metabolites changes could be served as potential therapeutic targets.
Citation Format: Gu G, Piyarathna B, Coarfa C, Ellis L, Ando' S, Fuqua S. The Y537S ESR1 mutation carries unique metabolomics profiling in breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-02-03.
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Affiliation(s)
- G Gu
- Baylor College of Medicine, Houston, TX; UC-Irvine and the Tibor Rubin VA Medical Center University of California, Long Beach, CA; University of Calabria, Rende, Calabria, Italy
| | - B Piyarathna
- Baylor College of Medicine, Houston, TX; UC-Irvine and the Tibor Rubin VA Medical Center University of California, Long Beach, CA; University of Calabria, Rende, Calabria, Italy
| | - C Coarfa
- Baylor College of Medicine, Houston, TX; UC-Irvine and the Tibor Rubin VA Medical Center University of California, Long Beach, CA; University of Calabria, Rende, Calabria, Italy
| | - L Ellis
- Baylor College of Medicine, Houston, TX; UC-Irvine and the Tibor Rubin VA Medical Center University of California, Long Beach, CA; University of Calabria, Rende, Calabria, Italy
| | - S Ando'
- Baylor College of Medicine, Houston, TX; UC-Irvine and the Tibor Rubin VA Medical Center University of California, Long Beach, CA; University of Calabria, Rende, Calabria, Italy
| | - S Fuqua
- Baylor College of Medicine, Houston, TX; UC-Irvine and the Tibor Rubin VA Medical Center University of California, Long Beach, CA; University of Calabria, Rende, Calabria, Italy
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Gu G, Na Y, Chung H, Seok SH, Lee HY. Zebrafish Larvae Model of Dilated Cardiomyopathy Induced by Terfenadine. Korean Circ J 2017; 47:960-969. [PMID: 29035434 PMCID: PMC5711688 DOI: 10.4070/kcj.2017.0080] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 07/10/2017] [Accepted: 07/27/2017] [Indexed: 12/20/2022] Open
Abstract
Background and Objectives Dilated cardiomyopathy can be the end-stage of severe cardiac disorders and directly affects the cardiac muscle, inducing cardiomegaly and heart failure (HF). Although a wide variety of animal models are available to study dilated cardiomyopathy, there is no model to assess dilated cardiomyopathy with non-invasive, simple, and large screening methods. Methods We developed a dilated cardiomyopathy model in zebrafish larvae using short duration terfenadine, a known cardiotoxic drug that induces ventricular size dilation. Fractional shortening of zebrafish hearts was calculated. Results We treated zebrafish with 5 to 10 µM terfenadine for 24 hours. In terfenadine-treated zebrafish, blood frequently pooled and clotted in the chamber, and circulation was remarkably reduced. Atria and ventricles were swollen, and fluid was deposited around the heart, mimicking edema. Cardiac contractility was significantly reduced, and ventricular area was significantly enlarged. Heart rate was markedly reduced even after terfenadine withdrawal. Acridine orange staining also showed that terfenadine increased cardiomyocyte apoptosis. A significant increase of natriuretic peptide B (NPPB) mRNA was found in terfenadine-treated zebrafish. A low dose of terfenadine (5–10 µM) did not show mortality in short-term treatment (24 hours). However, moderate dose (35–45 µM) terfenadine treatment reduced zebrafish survival within 1 hour. Conclusion With advantages of rapid sample preparation procedure and transparent observation of the live heart, this model can potentially be applied to large-scale drug screening and toxicity assays for non-ischemic HF.
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Affiliation(s)
- Gyojeong Gu
- Department of Microbiology and Immunology, Institute of Endemic Disease, Seoul National University College of Medicine, Seoul, Korea
| | - Yirang Na
- Department of Microbiology and Immunology, Institute of Endemic Disease, Seoul National University College of Medicine, Seoul, Korea
| | - Hyewon Chung
- Department of Microbiology and Immunology, Institute of Endemic Disease, Seoul National University College of Medicine, Seoul, Korea
| | - Seung Hyeok Seok
- Department of Microbiology and Immunology, Institute of Endemic Disease, Seoul National University College of Medicine, Seoul, Korea.
| | - Hae Young Lee
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
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Fan G, Fu Q, Zhang J, Zhang H, Gu X, Wang C, Gu G, Guan X, Fan Y, He S. Radiation reduction of minimally invasive transforaminal lumbar interbody fusion with localisation system in overweight patients: practical technique. Bone Joint J 2017; 99-B:944-950. [PMID: 28663402 DOI: 10.1302/0301-620x.99b7.bjj-2016-0853.r1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 02/10/2017] [Indexed: 11/05/2022]
Abstract
AIMS Minimally invasive transforaminal lumbar interbody fusion (MITLIF) has been well validated in overweight and obese patients who are consequently subject to a higher radiation exposure. This prospective multicentre study aimed to investigate the efficacy of a novel lumbar localisation system for MITLIF in overweight patients. PATIENTS AND METHODS The initial study group consisted of 175 patients. After excluding 49 patients for various reasons, 126 patients were divided into two groups. Those in Group A were treated using the localisation system while those in Group B were treated by conventional means. The primary outcomes were the effective radiation dosage to the surgeon and the exposure time. RESULTS There were 62 patients in Group A and 64 in Group B. The mean effective dosage was 0.0217 mSv (standard deviation (sd) 0.0079) in Group A and 0.0383 mSv (sd 0.0104) in Group B (p < 0.001). The mean fluoroscopy exposure time was 26.42 seconds (sd 5.91) in Group A and 40.67 seconds (sd 8.18) in Group B (p < 0.001). The operating time was 175.56 minutes (sd 32.23) and 206.08 minutes (sd 30.15) (p < 0.001), respectively. The mean pre-operative localisation time was 4.73 minutes (sd 0.84) in Group A and 7.03 minutes (sd 1.51) in Group B (p < 0.001). The mean screw placement time was 47.37 minutes (sd 10.43) in Group A and 67.86 minutes (sd 14.15) in Group B (p < 0.001). The pedicle screw violation rate was 0.35% (one out of 283) in Group A and 2.79% (eight out of 287) in Group B (p = 0.020). CONCLUSION The study shows that the localisation system can effectively reduce radiation exposure, exposure time, operating time, pre-operative localisation time, and screw placement time in overweight patients undergoing MITLIF. Cite this article: Bone Joint J 2017;99-B:944-50.
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Affiliation(s)
- G Fan
- Tongji University School of Medicine, 301 Yanchang Road, Shanghai 200072, China
| | - Q Fu
- Ningbo No.2 Hospital, 41 Northwestern Road, Ningbo, Zhejiang 315099, China
| | - J Zhang
- Southeast Hospital affiliated to Xiamen University, 269 Zhanghua Road, Zhangzhou, Fujian 363020, China
| | - H Zhang
- Tongji University School of Medicine, 301 Yanchang Road, Shanghai 200072, China
| | - X Gu
- Tongji University School of Medicine, 301 Yanchang Road, Shanghai 200072, China
| | - C Wang
- Tongji University School of Medicine, 301 Yanchang Road, Shanghai 200072, China
| | - G Gu
- Tongji University School of Medicine, 301 Yanchang Road, Shanghai 200072, China
| | - X Guan
- Tongji University School of Medicine, 301 Yanchang Road, Shanghai 200072, China
| | - Y Fan
- Tongji University School of Medicine, 301 Yanchang Road, Shanghai 200072, China
| | - S He
- Tongji University School of Medicine, 301 Yanchang Road, Shanghai 200072, China
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Bello I, Lee R, Malinovsky I, Watkins L, Nossel I, Smith T, Ngo H, Birnbaum M, Marino L, Sederer LI, Radigan M, Gu G, Essock S, Dixon LB. OnTrackNY: The Development of a Coordinated Specialty Care Program for Individuals Experiencing Early Psychosis. Psychiatr Serv 2017; 68:318-320. [PMID: 27973999 PMCID: PMC5846122 DOI: 10.1176/appi.ps.201600512] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OnTrackNY is a coordinated specialty care program that delivers early intervention services to youths experiencing a first episode of nonaffective psychosis. Treatment aims to help individuals improve their mental health and achieve personal goals related to work, school, and social relationships. This column describes OnTrackNY's progression from a research project to real-world implementation. The authors describe the treatment model, approach to training and dissemination, and procedures for collecting and sharing data with OnTrackNY teams and provide data on client characteristics and selected outcomes.
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Affiliation(s)
- Iruma Bello
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
| | - Rufina Lee
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
| | - Igor Malinovsky
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
| | - Liza Watkins
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
| | - Ilana Nossel
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
| | - Thomas Smith
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
| | - Hong Ngo
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
| | - Michael Birnbaum
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
| | - Leslie Marino
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
| | - Lloyd I Sederer
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
| | - Marleen Radigan
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
| | - Gyojeong Gu
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
| | - Susan Essock
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
| | - Lisa B Dixon
- Dr. Bello, Dr. Malinovsky, Ms. Watkins, Dr. Nossel, Dr. Ngo, Dr. Marino, Dr. Essock, and Dr. Dixon are with the New York State Psychiatric Institute, New York City (e-mail: ). Dr. Essock and Dr. Dixon are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City. Dr. Lee is with the Silberman School of Social Work at Hunter College, City University of New York. Dr. Smith and Dr. Sederer are with the New York State Office of Mental Health (NYSOMH), New York City. Dr. Smith is also with the Department of Psychiatry, Columbia University Medical Center, New York City. Dr. Sederer is also with the Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City. Dr. Birnbaum is with the Department of Psychiatry, Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York. Dr. Radigan and Mr. Gu are with NYSOMH, Albany. Fred C. Osher, M.D., and Marvin S. Swartz, M.D., are editors of this column
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Fuqua SAW, Gu G, Rechoum Y, Gelsomino L, Dustin DJ, Corona-Rodriguez A, Beyer AR, Pejerrey SM, Gao M, Tsimelzon A, Tian L, Zhang X, Nagi C, Ando' S. Abstract S4-02: The Y537S ESR1 mutation is a dominant driver of distant ER-positive breast cancer metastasis. Cancer Res 2017. [DOI: 10.1158/1538-7445.sabcs16-s4-02] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Estrogen receptor (ESR1) mutations occur at a high frequency in metastatic breast tumors in patients treated with hormonal therapy in the metastatic setting. We do not know if these mutations are involved in metastasis.
Experimental design and methods: We generated ESR1 Y537S homozygous mutations using CRISPR Casp-9 technology. Treatment synergy was evaluated using Compusyn. Athymic mice were used in tumor xenograft studies. ChIP-Seq and transcriptome analyses were performed.
Results: We generated CRISPR ESR1 Y537S mutation homozygous knock-in clones and lentiviral stable pools in MCF-7 cells. Transcriptome profiling revealed elevated expression of Hallmark pathways, including EMT and estrogen-regulated gene expression. The EMT in mutant cells was associated with a switch from E-cadherin to vimentin, and increased expression of SNAIL and TWIST. Mutant cell growth was resistant to tamoxifen, but responsive to fulvestrant treatment. Synergistic treatment effects were observed with fulvestrant and everolimus or palbociclib. CRISPR Y537S mutant knock-in cells grown in the mammary fat-pad of athymic mice spontaneously metastasized to distant organs including the lung, intestine, and kidneys. In the presence of estrogen, there was no difference in the frequency of distant macrometastases between parental wild-type ER and CRISPR Y537S mutant ER mice. However, in the absence of estrogen, 80% of CRISPR Y537S mutant ER mice displayed overt distant macrometastases, but none were observed in parental wild-type ER mice (p=0.04). Interestingly, although CRISPR Y537S mutant ER tumors grown in the mammary fat-pad were unresponsive to tamoxifen treatment, tamoxifen significantly inhibited the growth of mutant tumors at the distant microenvironment (8-fold). Distant tumors retained ER expression and hormone sensitivity. Comparison of residual tamoxifen-treated metastatic tumors with tumors grown at the primary mammary fat-pad site using immunoblot analysis demonstrated significant reduction in estrogen-regulated gene expression, but no effect on the expression of biomarkers associated with EMT, suggesting a disconnect between EMT and distant metastasis in mutant cells. EMT genes were also identified as direct binding site targets in Y537S mutant cells compared with wide-type ER using ChIPSeq. We discovered that expression of the Y537S mutant was dominant, driving the growth of distant metastatic tumors when co-expressed with wild-type ER cells. A Y537S ER mutant-specific gene expression signature predicted poor disease-free survival of ER-positive patients using the METABRIC database, and lung-specific metastasis-free survival in a Memorial Sloan Kettering dataset.
Conclusion: The Y537S ER mutation is a driver of distant metastasis in ER-positive breast cancer cells. Although tamoxifen treatment was ineffective at reducing the growth of mutant cells grown at the primary site, it was effective at reducing distant metastasis. A Y537S ER mutant-specific gene expression signature predicted poor disease-free, and distant lung metastasis in ER-positive patients. Mutation status is a potential new predictive factor for hormone therapy of metastatic breast cancer patients on maintenance hormonal therapy.
Citation Format: Fuqua SAW, Gu G, Rechoum Y, Gelsomino L, Dustin DJ, Corona-Rodriguez A, Beyer AR, Pejerrey SM, Gao M, Tsimelzon A, Tian L, Zhang X, Nagi C, Ando' S. The Y537S ESR1 mutation is a dominant driver of distant ER-positive breast cancer metastasis [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr S4-02.
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Affiliation(s)
- SAW Fuqua
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
| | - G Gu
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
| | - Y Rechoum
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
| | - L Gelsomino
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
| | - DJ Dustin
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
| | - A Corona-Rodriguez
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
| | - AR Beyer
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
| | - SM Pejerrey
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
| | - M Gao
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
| | - A Tsimelzon
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
| | - L Tian
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
| | - X Zhang
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
| | - C Nagi
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
| | - S Ando'
- Baylor College of Medicine, Houston, TX; University of Calabria, Cosenza, Calabria, Italy; MD Anderson Cancer Center, Housotn, TX
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Carruthers J, Radigan M, Erlich MD, Gu G, Wang R, Frimpong EY, Essock SM, Olfson M, Castillo EG, Miller GA, Sederer LI, Stroup TS. An Initiative to Improve Clozapine Prescribing in New York State. Psychiatr Serv 2016; 67:369-71. [PMID: 26725299 DOI: 10.1176/appi.ps.201500493] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Clozapine remains the only medication approved for treatment-resistant schizophrenia. But underuse is the norm. In 2010, the New York State Office of Mental Health began a multifaceted initiative to promote the evidence-based use of clozapine. From 2009 to 2013, in the absence of a well-funded pharmaceutical marketing campaign, the proportion of new clozapine trials among all new outpatient antipsychotic trials increased 40% among adult New York Medicaid recipients with a diagnosis of schizophrenia. The largest gains occurred in state-operated clinics. New York's experience demonstrates the feasibility of making clozapine more accessible to patients who stand to benefit most.
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Affiliation(s)
- Jay Carruthers
- Dr. Carruthers, Dr. Radigan, Dr. Erlich, Mr. Gu, Mr. Wang, Dr. Frimpong, Dr. Miller, and Dr. Sederer are with the New York State Office of Mental Health, Albany (e-mail: ). Dr. Carruthers is also with the Department of Psychiatry, Albany Medical College, Albany, New York. Dr. Radigan and Dr. Erlich are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City, where Dr. Essock and Dr. Stroup are affiliated. Dr. Sederer is also with the Mailman School of Public Health, Columbia University, New York City. Dr. Essock and Dr. Stroup are also with the New York State Psychiatric Institute, New York City, where Dr. Olfson is affiliated. Dr. Olfson is also with Columbia University Medical Center, New York City. Dr. Castillo is with the Robert Wood Johnson Foundation Clinical Scholars Program, University of California, Los Angeles. Marcela Horvitz-Lennon, M.D., M.P.H., is editor of this column
| | - Marleen Radigan
- Dr. Carruthers, Dr. Radigan, Dr. Erlich, Mr. Gu, Mr. Wang, Dr. Frimpong, Dr. Miller, and Dr. Sederer are with the New York State Office of Mental Health, Albany (e-mail: ). Dr. Carruthers is also with the Department of Psychiatry, Albany Medical College, Albany, New York. Dr. Radigan and Dr. Erlich are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City, where Dr. Essock and Dr. Stroup are affiliated. Dr. Sederer is also with the Mailman School of Public Health, Columbia University, New York City. Dr. Essock and Dr. Stroup are also with the New York State Psychiatric Institute, New York City, where Dr. Olfson is affiliated. Dr. Olfson is also with Columbia University Medical Center, New York City. Dr. Castillo is with the Robert Wood Johnson Foundation Clinical Scholars Program, University of California, Los Angeles. Marcela Horvitz-Lennon, M.D., M.P.H., is editor of this column
| | - Matthew D Erlich
- Dr. Carruthers, Dr. Radigan, Dr. Erlich, Mr. Gu, Mr. Wang, Dr. Frimpong, Dr. Miller, and Dr. Sederer are with the New York State Office of Mental Health, Albany (e-mail: ). Dr. Carruthers is also with the Department of Psychiatry, Albany Medical College, Albany, New York. Dr. Radigan and Dr. Erlich are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City, where Dr. Essock and Dr. Stroup are affiliated. Dr. Sederer is also with the Mailman School of Public Health, Columbia University, New York City. Dr. Essock and Dr. Stroup are also with the New York State Psychiatric Institute, New York City, where Dr. Olfson is affiliated. Dr. Olfson is also with Columbia University Medical Center, New York City. Dr. Castillo is with the Robert Wood Johnson Foundation Clinical Scholars Program, University of California, Los Angeles. Marcela Horvitz-Lennon, M.D., M.P.H., is editor of this column
| | - Gyojeong Gu
- Dr. Carruthers, Dr. Radigan, Dr. Erlich, Mr. Gu, Mr. Wang, Dr. Frimpong, Dr. Miller, and Dr. Sederer are with the New York State Office of Mental Health, Albany (e-mail: ). Dr. Carruthers is also with the Department of Psychiatry, Albany Medical College, Albany, New York. Dr. Radigan and Dr. Erlich are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City, where Dr. Essock and Dr. Stroup are affiliated. Dr. Sederer is also with the Mailman School of Public Health, Columbia University, New York City. Dr. Essock and Dr. Stroup are also with the New York State Psychiatric Institute, New York City, where Dr. Olfson is affiliated. Dr. Olfson is also with Columbia University Medical Center, New York City. Dr. Castillo is with the Robert Wood Johnson Foundation Clinical Scholars Program, University of California, Los Angeles. Marcela Horvitz-Lennon, M.D., M.P.H., is editor of this column
| | - Rui Wang
- Dr. Carruthers, Dr. Radigan, Dr. Erlich, Mr. Gu, Mr. Wang, Dr. Frimpong, Dr. Miller, and Dr. Sederer are with the New York State Office of Mental Health, Albany (e-mail: ). Dr. Carruthers is also with the Department of Psychiatry, Albany Medical College, Albany, New York. Dr. Radigan and Dr. Erlich are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City, where Dr. Essock and Dr. Stroup are affiliated. Dr. Sederer is also with the Mailman School of Public Health, Columbia University, New York City. Dr. Essock and Dr. Stroup are also with the New York State Psychiatric Institute, New York City, where Dr. Olfson is affiliated. Dr. Olfson is also with Columbia University Medical Center, New York City. Dr. Castillo is with the Robert Wood Johnson Foundation Clinical Scholars Program, University of California, Los Angeles. Marcela Horvitz-Lennon, M.D., M.P.H., is editor of this column
| | - Eric Y Frimpong
- Dr. Carruthers, Dr. Radigan, Dr. Erlich, Mr. Gu, Mr. Wang, Dr. Frimpong, Dr. Miller, and Dr. Sederer are with the New York State Office of Mental Health, Albany (e-mail: ). Dr. Carruthers is also with the Department of Psychiatry, Albany Medical College, Albany, New York. Dr. Radigan and Dr. Erlich are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City, where Dr. Essock and Dr. Stroup are affiliated. Dr. Sederer is also with the Mailman School of Public Health, Columbia University, New York City. Dr. Essock and Dr. Stroup are also with the New York State Psychiatric Institute, New York City, where Dr. Olfson is affiliated. Dr. Olfson is also with Columbia University Medical Center, New York City. Dr. Castillo is with the Robert Wood Johnson Foundation Clinical Scholars Program, University of California, Los Angeles. Marcela Horvitz-Lennon, M.D., M.P.H., is editor of this column
| | - Susan M Essock
- Dr. Carruthers, Dr. Radigan, Dr. Erlich, Mr. Gu, Mr. Wang, Dr. Frimpong, Dr. Miller, and Dr. Sederer are with the New York State Office of Mental Health, Albany (e-mail: ). Dr. Carruthers is also with the Department of Psychiatry, Albany Medical College, Albany, New York. Dr. Radigan and Dr. Erlich are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City, where Dr. Essock and Dr. Stroup are affiliated. Dr. Sederer is also with the Mailman School of Public Health, Columbia University, New York City. Dr. Essock and Dr. Stroup are also with the New York State Psychiatric Institute, New York City, where Dr. Olfson is affiliated. Dr. Olfson is also with Columbia University Medical Center, New York City. Dr. Castillo is with the Robert Wood Johnson Foundation Clinical Scholars Program, University of California, Los Angeles. Marcela Horvitz-Lennon, M.D., M.P.H., is editor of this column
| | - Mark Olfson
- Dr. Carruthers, Dr. Radigan, Dr. Erlich, Mr. Gu, Mr. Wang, Dr. Frimpong, Dr. Miller, and Dr. Sederer are with the New York State Office of Mental Health, Albany (e-mail: ). Dr. Carruthers is also with the Department of Psychiatry, Albany Medical College, Albany, New York. Dr. Radigan and Dr. Erlich are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City, where Dr. Essock and Dr. Stroup are affiliated. Dr. Sederer is also with the Mailman School of Public Health, Columbia University, New York City. Dr. Essock and Dr. Stroup are also with the New York State Psychiatric Institute, New York City, where Dr. Olfson is affiliated. Dr. Olfson is also with Columbia University Medical Center, New York City. Dr. Castillo is with the Robert Wood Johnson Foundation Clinical Scholars Program, University of California, Los Angeles. Marcela Horvitz-Lennon, M.D., M.P.H., is editor of this column
| | - Enrico G Castillo
- Dr. Carruthers, Dr. Radigan, Dr. Erlich, Mr. Gu, Mr. Wang, Dr. Frimpong, Dr. Miller, and Dr. Sederer are with the New York State Office of Mental Health, Albany (e-mail: ). Dr. Carruthers is also with the Department of Psychiatry, Albany Medical College, Albany, New York. Dr. Radigan and Dr. Erlich are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City, where Dr. Essock and Dr. Stroup are affiliated. Dr. Sederer is also with the Mailman School of Public Health, Columbia University, New York City. Dr. Essock and Dr. Stroup are also with the New York State Psychiatric Institute, New York City, where Dr. Olfson is affiliated. Dr. Olfson is also with Columbia University Medical Center, New York City. Dr. Castillo is with the Robert Wood Johnson Foundation Clinical Scholars Program, University of California, Los Angeles. Marcela Horvitz-Lennon, M.D., M.P.H., is editor of this column
| | - Gregory A Miller
- Dr. Carruthers, Dr. Radigan, Dr. Erlich, Mr. Gu, Mr. Wang, Dr. Frimpong, Dr. Miller, and Dr. Sederer are with the New York State Office of Mental Health, Albany (e-mail: ). Dr. Carruthers is also with the Department of Psychiatry, Albany Medical College, Albany, New York. Dr. Radigan and Dr. Erlich are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City, where Dr. Essock and Dr. Stroup are affiliated. Dr. Sederer is also with the Mailman School of Public Health, Columbia University, New York City. Dr. Essock and Dr. Stroup are also with the New York State Psychiatric Institute, New York City, where Dr. Olfson is affiliated. Dr. Olfson is also with Columbia University Medical Center, New York City. Dr. Castillo is with the Robert Wood Johnson Foundation Clinical Scholars Program, University of California, Los Angeles. Marcela Horvitz-Lennon, M.D., M.P.H., is editor of this column
| | - Lloyd I Sederer
- Dr. Carruthers, Dr. Radigan, Dr. Erlich, Mr. Gu, Mr. Wang, Dr. Frimpong, Dr. Miller, and Dr. Sederer are with the New York State Office of Mental Health, Albany (e-mail: ). Dr. Carruthers is also with the Department of Psychiatry, Albany Medical College, Albany, New York. Dr. Radigan and Dr. Erlich are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City, where Dr. Essock and Dr. Stroup are affiliated. Dr. Sederer is also with the Mailman School of Public Health, Columbia University, New York City. Dr. Essock and Dr. Stroup are also with the New York State Psychiatric Institute, New York City, where Dr. Olfson is affiliated. Dr. Olfson is also with Columbia University Medical Center, New York City. Dr. Castillo is with the Robert Wood Johnson Foundation Clinical Scholars Program, University of California, Los Angeles. Marcela Horvitz-Lennon, M.D., M.P.H., is editor of this column
| | - T Scott Stroup
- Dr. Carruthers, Dr. Radigan, Dr. Erlich, Mr. Gu, Mr. Wang, Dr. Frimpong, Dr. Miller, and Dr. Sederer are with the New York State Office of Mental Health, Albany (e-mail: ). Dr. Carruthers is also with the Department of Psychiatry, Albany Medical College, Albany, New York. Dr. Radigan and Dr. Erlich are also with the Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York City, where Dr. Essock and Dr. Stroup are affiliated. Dr. Sederer is also with the Mailman School of Public Health, Columbia University, New York City. Dr. Essock and Dr. Stroup are also with the New York State Psychiatric Institute, New York City, where Dr. Olfson is affiliated. Dr. Olfson is also with Columbia University Medical Center, New York City. Dr. Castillo is with the Robert Wood Johnson Foundation Clinical Scholars Program, University of California, Los Angeles. Marcela Horvitz-Lennon, M.D., M.P.H., is editor of this column
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Yang L, Xu Q, Xie H, Gu G, Jiang J. Expression of serum miR-218 in hepatocellular carcinoma and its prognostic significance. Clin Transl Oncol 2015; 18:841-7. [PMID: 26586116 DOI: 10.1007/s12094-015-1447-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Accepted: 11/03/2015] [Indexed: 02/06/2023]
Abstract
BACKGROUND Several recent studies have revealed that microRNAs (miRNAs) are stably detectable in the circulation and can be used as biomarkers for diagnosis and prognosis of malignancy. The aim of this manuscript is to investigate serum miR-218 expression in patients with hepatocellular carcinoma (HCC) and to analyze its potential diagnostic and prognostic value in HCC. METHODS Quantitative real-time quantitative PCR (qPCR) was conducted to detect serum miR-218 expression from 156 HCC and 98 benign liver diseases (BLD) as well as 64 healthy controls. The relevance of serum miR-218 expression to the clinicopathological factors was assessed. In addition, the prediction of cutoff values of the markers was performed by the receiver operating characteristic (ROC) curve. Moreover, the Kaplan-Meier method was used to plot survival curves and univariable and multivariable Cox regression analyses were used to evaluate independent prognostic factors. RESULTS Consequently, our findings revealed that serum miR-218 levels were remarkably underexpressed in HCC patients as compared to BLD patients and healthy controls. And its low level was obviously related to tumor size (p = 0.048), tumor number (p = 0.018), vascular invasion (p = 0.039), Edmondson grade (p = 0.042), and higher TNM stage (III-IV). ROC curve analysis showed that miR-218 had a significant diagnostic accuracy, yielded an AUC (the areas under the ROC curve) of 0.734 (95 % confidence interval (CI) 0.68-0.789, p < 0.01), thus providing a sensitivity of 66.7 % and a specificity of 69.1 % in discriminating HCC from BLD and healthy controls. Meanwhile, miR-218 can act as a useful biomarker in distinguishing the patients with large tumors (>5 cm) from patients with small tumors (<5 cm) (p < 0.01). In addition, the combination of miR-218 and AFP had greater diagnosis capacity with an AUC of 0.908 (95 % CI 0.876-0.940; p < 0.01). Both log-rank test and Cox regression analysis demonstrated that the decreased serum expression of miR-218 had a significant impact on overall survival of the patients with HCC (HR = 3.049, 95 % CI 2.028-4.585, p < 0.01). CONCLUSION Taken together, this study suggested that serum expression of miR-218 might be a potential noninvasive tumor biomarker in the diagnosis and assessment of prognosis of HCC.
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Affiliation(s)
- L Yang
- Department of Hepatopancreatobiliary Surgery, Ningbo First Hospital, Ningbo, 315010, China
| | - Q Xu
- Department of Hepatopancreatobiliary Surgery, Ningbo First Hospital, Ningbo, 315010, China
| | - H Xie
- Department of Hepatopancreatobiliary Surgery, Ningbo First Hospital, Ningbo, 315010, China
| | - G Gu
- Department of Hepatopancreatobiliary Surgery, Ningbo First Hospital, Ningbo, 315010, China
| | - J Jiang
- Department of Hepatopancreatobiliary Surgery, Ningbo First Hospital, Ningbo, 315010, China.
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Gu G, Wang Y. Uneven intensity change correction of speckle images using morphological Top-Hat transform in digital image correlation. The Imaging Science Journal 2015. [DOI: 10.1179/1743131x15y.0000000026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Ren W, Gu G. Prognostic implications of RB1 tumour suppressor gene alterations in the clinical outcome of human osteosarcoma: a meta-analysis. Eur J Cancer Care (Engl) 2015; 26. [PMID: 26503016 DOI: 10.1111/ecc.12401] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2015] [Indexed: 12/01/2022]
Abstract
Primary osteosarcoma is the most frequent malignant bone cancer in children and teenagers. Genetic alterations at the retinoblastoma 1 (RB1) gene has been implicated in the development and progression of human osteosarcoma. Here, we performed a meta-analysis to examine the impact of RB1 mutations on the survival of osteosarcoma patients, the risk of metastasis and the histological response of osteosarcoma to chemotherapy. A systemic review of the Medline, Embase, Scopus and Cochrane Library yielded 12 eligible studies with 491 patients for this study. Forest plots resulting from our meta-analyses illustrate that loss of RB1 function results in a 1.62-fold increase in the mortality rate for osteosarcoma patients (RR = 1.62, 95% CI: 1.23-2.13; Z = 3.44, P = 0.0006), a significant increase in osteosarcoma metastasis (OR = 3.95, 95% CI: 1.86-8.38; Z = 3.57; P = 0.0004), and a significant reduction in the histological response of osteosarcoma to chemotherapy (OR = 0.35; 95% CI: 0.13-0.94; Z = -2.08; P = 0.038). Additionally, the nearly symmetrical funnel plot (Egger's test, t = 1.15, P = 0.288) indicates absence of publication bias regarding the meta-analysis that examined the correlation of RB1 alterations with the survival rate for osteosarcoma patients. Our findings suggest that RB1 alterations may serve as a prognostic marker for the management of osteosarcoma patients.
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Affiliation(s)
- W Ren
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, Jilin, China
| | - G Gu
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, Jilin, China
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Wu Y, Ren J, Zhou B, Ding C, Chen J, Wang G, Gu G, Wu X, Liu S, Hu D, Li J. Gene silencing of non-obese diabetic receptor family (NLRP3) protects against the sepsis-induced hyper-bile acidaemia in a rat model. Clin Exp Immunol 2015; 179:277-93. [PMID: 25228381 DOI: 10.1111/cei.12457] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/12/2014] [Indexed: 01/08/2023] Open
Abstract
The role of NOD-like receptor family (NLRP3) has been confirmed in various inflammatory diseases. The association between NLRP3 and hyper-bileacidaemia during the sepsis remains unclear. We aimed to investigate whether NLRP3 silencing protects against the sepsis-induced hyper-bileacidaemia. Sepsis was induced by caecum ligation and puncture (CLP). Gene silencing of NLRP3 was performed by injecting rats with NLRP3 short hairpin RNA plasmids (NLRP3 shRNA) 48 h before surgery. Rats were divided into four groups: group 1: sham; group 2: sepsis; group 3: NLRP3 shRNA + sepsis (called the 'NLRP3 shRNA' group); and group 4: scrambled shRNA + sepsis (called the 'scrambled shRNA' group). The serum levels of bile acids, hepatic expression of hepatocyte membrane transporters, hepatic cytokine levels and behaviours of immune cells were compared among the groups. Hepatic NLRP3 expression was increased dramatically during the sepsis, but was suppressed by pretreatment with NLRP3 shRNA. Compared with rats in the sepsis and the scrambled shRNA groups, rats in the NLRP3 shRNA group exhibited significantly decreased serum levels of glycine and taurine conjugated-bile acids, with rehabilitated expression of hepatocyte transporters, suppressed hepatic cytokine levels, decreased hepatic neutrophils infiltration and attenuated macrophages pyroptosis. Gene silencing of NLRP3 ameliorates sepsis-induced hyper-bileacidaemia by rehabilitating hepatocyte transporter expression, reducing hepatic cytokine levels, neutrophil infiltration and macrophages pyroptosis. NLRP3 may be a pivotal target for sepsis management.
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Affiliation(s)
- Y Wu
- Department of Surgery, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
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Gu G, Zhang W, Li M, Ni J, Wang P. Transplantation of NSC-derived cholinergic neuron-like cells improves cognitive function in APP/PS1 transgenic mice. Neuroscience 2015; 291:81-92. [PMID: 25681520 DOI: 10.1016/j.neuroscience.2015.01.073] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 01/30/2015] [Accepted: 01/30/2015] [Indexed: 01/10/2023]
Abstract
The ability to selectively control the differentiation of neural stem cells (NSCs) into cholinergic neurons in vivo would be an important step toward cell replacement therapy. First, green fluorescent protein (GFP)-NSCs were induced to differentiate into cholinergic neuron-like cells (CNLs) with retinoic acid (RA) pre-induction followed by nerve growth factor (NGF) induction. Then, these CNLs were transplanted into bilateral hippocampus of APP/PS1 transgenic mice. Behavioral parameters showed by Morris water maze (MWM) tests and the percentages of GFP-labeled cholinergic neurons of CNL transplanted mice were compared with those of controls. Brain levels of choline acetyltransferase (ChAT) mRNA and proteins were analyzed by quantitative real-time PCR and Western blotting, ChAT activity and acetylcholine (ACh) concentration were also evaluated by ChAT activity and ACh concentration assay kits. Immunofluorescence analysis showed that 80.3±1.5% NSCs differentiated into CNLs after RA pre-induction followed by NGF induction in vitro. Three months after transplantation, 82.4±6.3% CNLs differentiated into cholinergic neurons in vivo. APP/PS1 mice transplanted with CNLs showed a significant improvement in learning and memory ability compared with control groups at different time points. Furthermore, CNLs transplantation dramatically increased in the expressions of ChAT mRNA and protein, as well ChAT activity and ACh concentration in APP/PS1 mice. Our findings support the prospect of using NSC-derived CNLs in developing therapies for Alzheimer's disease (AD).
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Affiliation(s)
- G Gu
- Department of Medical Imaging, Tongji Hospital, Medical School of Tongji University, Shanghai 200065, China
| | - W Zhang
- Department of Medical Imaging, Tongji Hospital, Medical School of Tongji University, Shanghai 200065, China
| | - M Li
- Department of Medical Imaging, Tongji Hospital, Medical School of Tongji University, Shanghai 200065, China
| | - J Ni
- Department of Medical Imaging, Tongji Hospital, Medical School of Tongji University, Shanghai 200065, China
| | - P Wang
- Department of Medical Imaging, Tongji Hospital, Medical School of Tongji University, Shanghai 200065, China.
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Bruin H, Fokkink R, Gu G, Roos C. On the chaotic behavior of the primal-dual affine-scaling algorithm for linear optimization. Chaos 2014; 24:043132. [PMID: 25554052 DOI: 10.1063/1.4902900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We study a one-parameter family of quadratic maps, which serves as a template for interior point methods. It is known that such methods can exhibit chaotic behavior, but this has been verified only for particular linear optimization problems. Our results indicate that this chaotic behavior is generic.
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Affiliation(s)
- H Bruin
- Faculty of Mathematics, University of Vienna, Oskar Morgensternplatz 1 A-1090 Vienna, Austria
| | - R Fokkink
- Delft University, Faculty of Electrical Engineering, Mathematics and Computer Science, P.O. Box 5031, 2600 GA Delft, Netherlands
| | - G Gu
- Department of Mathematics, Nanjing University, Nanjing 210093, China
| | - C Roos
- Delft University, Faculty of Electrical Engineering, Mathematics and Computer Science, P.O. Box 5031, 2600 GA Delft, Netherlands
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Liu L, Park J, Siegel DA, McCarty KF, Clark KW, Deng W, Basile L, Idrobo JC, Li AP, Gu G. Heteroepitaxial Growth of Two-Dimensional Hexagonal Boron Nitride Templated by Graphene Edges. Science 2014; 343:163-7. [DOI: 10.1126/science.1246137] [Citation(s) in RCA: 433] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Tatarkiewicz K, Belanger P, Gu G, Parkes D, Roy D. No evidence of drug-induced pancreatitis in rats treated with exenatide for 13 weeks. Diabetes Obes Metab 2013; 15:417-26. [PMID: 23163898 PMCID: PMC3654567 DOI: 10.1111/dom.12040] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 09/29/2012] [Accepted: 11/12/2012] [Indexed: 12/18/2022]
Abstract
AIMS The potential association of glucagon-like peptide receptor agonists (GLP-1RAs) with the development of pancreatitis or pancreatic malignancies in patients with diabetes has been suggested. This study evaluated the long-term effects of the GLP-1RA exenatide on pancreatic exocrine structure and function in the Zucker diabetic fatty (ZDF) rat model of type 2 diabetes. METHODS Rats received subcutaneous twice-daily injections of 0 (control), 6, 40 and 250 µg/kg/day exenatide for 3 months. Clinical signs, body and pancreas weight, food consumption, HbA1c, fasting serum amylase, lipase, glucose and insulin concentrations were evaluated during treatment and after a 28-day off-drug period to assess the reversibility of any observed effects. Morphometric analysis of pancreatic ductal cell proliferation and apoptosis were performed. RESULTS Plasma exenatide concentrations were several-fold higher than therapeutic levels observed in humans. No exenatide-related effects were observed on clinical signs, lipase concentration, pancreatic weight, pancreatic histology, ductal cell proliferation or apoptosis. Exenatide improved animal survival, physical condition, glucose concentrations and HbA1c, decreased food intake, and increased serum insulin concentration. Total amylase concentrations, although within normal ranges, were slightly higher in exenatide-treated rats; following the off-drug period, total amylase concentrations were comparable in treated and untreated rats. Exenatide-related minimal-to-moderate islet hypertrophy was observed at doses ≥6 µg/kg/day, with dose-related increases in incidence and degree. These changes were still present after the off-drug period. CONCLUSIONS Chronic administration of exenatide in ZDF rats resulted in the expected metabolic benefits and improved animal survival, with no adverse effects noted on pancreatic exocrine structure and function.
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Arham HZ, Hunt CR, Park WK, Gillett J, Das SD, Sebastian SE, Xu ZJ, Wen JS, Lin ZW, Li Q, Gu G, Thaler A, Budko SL, Canfield PC, Greene LH. Gap-like feature in the normal state of X(Fe1−xCox)2As2, X = Ba, Sr and Fe1+yTe revealed by Point Contact Spectroscopy. ACTA ACUST UNITED AC 2012. [DOI: 10.1088/1742-6596/400/2/022001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Gu G, Covington K, Rechoum Y, O'Malley B, Mangelsdorf D, Minna J, Webb P, Fuqua S. Abstract P4-08-09: Targeting Thyroid Receptor b in Estrogen Receptor Negative Breast Cancer. Cancer Res 2012. [DOI: 10.1158/0008-5472.sabcs12-p4-08-09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: The treatment of estrogen receptor (ER)-negative breast cancer (BC) is a major clinical problem due to the lack of useful therapeutic targets. Nuclear receptors (NRs) are potential targets in these patients because they regulate global transcriptional events and many already have agonists/antagonists available.
Material and Methods: We used microarray analysis of 227 ER-negative tumors to identify NR targets, and performed hierarchical clustering using 41 NRs. Expressed receptors were scored using prediction analysis of microarrays (PAM) across clustered groups. Cell lines were matched to subtypes using previously described data (Neve et al. 2006). Candidate gene expression levels were confirmed by qRT-PCR using TaqMan probes. pGIPZ lentiviral vectors encoding shRNA were used to knockdownselected candidates. MTT and soft agar assays were used to measure chemosensitivity and growth following treatment with Docetaxel (Doc), Doxorubicin (Dox), or Cisplatin (Cis). Statistical analysis was performed using Red-R.
Results: The 41 NRs clustered tumors into 5 groups. For each group we selected genes representing the highest ranked discriminators, and examined their effects in cell lines matching each groups' gene signature. Thyroid hormone receptor b (THRβ) was selected from group V. The expression levels of this receptor were confirmed by qRT-PCR and Western blot analysis.
Knockdown of THRβ in ER-negative HCC2185 cells rendered cells more resistant to all chemotherapeutics by using MTT assay. Similar results were confirmed in ER-negative MDA-MB-453 and HCC202 cells. Knockdown of THRβ enhanced colony forming potential in anchorage-independent soft agar assays in MDA-MB-453 and HCC202 cells. Statistical analysis using clinical data from Sabatier et al. (BCRT 2011) showed that patients with low THRb have a worse clinical outcome. In order to translate these findings into the clinic, we treated cells with a specific THRβ agonists, GC-1 and KB-141. GC-1 inhibited cell growth in growth assays, and synergistic effects were observed when cells were treated with GC-1 and Docetaxel in combination. Re-expression of ERα protein was observed in ER-nagative cells lines after treatment with GC-1 and KB141, suggesting that modulation of THRβ may also extend hormonal therapy to this hormonally insensitive group of patients.
Conclusion: Clinical targeting of NRs in ER-negative BCs is a novel strategy since receptors can be specifically targeted with ligands. Our data suggest that chemotherapy response in ER-negative patients overexpressing THRβ could be enhanced with a THRβ agonist. Similarly, functional re-activation of ERα by activating THRβ might extend hormonal therapies to these patients as well.
Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-08-09.
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Affiliation(s)
- G Gu
- Baylor College of Medicine, Houston, TX; UT Southwestern Medical Center; The Methodist Hospital Research Institute
| | - K Covington
- Baylor College of Medicine, Houston, TX; UT Southwestern Medical Center; The Methodist Hospital Research Institute
| | - Y Rechoum
- Baylor College of Medicine, Houston, TX; UT Southwestern Medical Center; The Methodist Hospital Research Institute
| | - B O'Malley
- Baylor College of Medicine, Houston, TX; UT Southwestern Medical Center; The Methodist Hospital Research Institute
| | - D Mangelsdorf
- Baylor College of Medicine, Houston, TX; UT Southwestern Medical Center; The Methodist Hospital Research Institute
| | - J Minna
- Baylor College of Medicine, Houston, TX; UT Southwestern Medical Center; The Methodist Hospital Research Institute
| | - P Webb
- Baylor College of Medicine, Houston, TX; UT Southwestern Medical Center; The Methodist Hospital Research Institute
| | - S Fuqua
- Baylor College of Medicine, Houston, TX; UT Southwestern Medical Center; The Methodist Hospital Research Institute
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Liu X, Lu M, Gu G, Lu T. Aza-Michael reactions in water using functionalized ionic liquids as the recyclable catalysts. JICS 2012. [DOI: 10.1007/bf03245908] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Dooley MJ, Wiseman M, Gu G. Prevalence of error-prone abbreviations used in medication prescribing for hospitalised patients: multi-hospital evaluation. Intern Med J 2012; 42:e19-22. [PMID: 22432997 DOI: 10.1111/j.1445-5994.2011.02697.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The use of error-prone abbreviations in prescribing is a potential cause of misinterpretation that may lead to medication error. This study determined frequency and type of error-prone abbreviations in inpatient medication prescribing across three Australian hospitals. Three hundred and sixty-nine (76.9%) patients had one or more error-prone abbreviations used in prescribing, with 8.4% of orders containing at least one error-prone abbreviation and 29.6% of these considered to be high risk for causing significant harm.
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Affiliation(s)
- M J Dooley
- Pharmacy Department, Alfred Health, Australia.
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Zhu HM, Qin L, Garnero P, Genant HK, Zhang G, Dai K, Yao X, Gu G, Hao Y, Li Z, Zhao Y, Li W, Yang J, Zhao X, Shi D, Fuerst T, Lu Y, Li H, Zhang X, Li C, Zhao J, Wu Q, Zhao SJ. The first multicenter and randomized clinical trial of herbal Fufang for treatment of postmenopausal osteoporosis. Osteoporos Int 2012; 23:1317-27. [PMID: 21505910 DOI: 10.1007/s00198-011-1577-2] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Accepted: 01/22/2011] [Indexed: 10/18/2022]
Abstract
UNLABELLED This multicenter and randomized clinical trial showed that daily oral herbal formula Xian Ling Gu Bao (XLGB) was safe in postmenopausal women over a 1-year treatment. Those patients (n ∼ 50) treated with XLGB at the conventional dose demonstrated a statistically significant increase in dual-energy X-ray absorptiometry (DXA) bone mineral density (BMD) at lumbar spine at 6 months and a numerically increased BMD at 12 months. INTRODUCTION The aim of this study was to examine the safety and efficacy of a herbal formula XLGB in postmenopausal women (ChiCTR-TRC-00000347). METHODS One hundred eighty healthy postmenopausal women (≥60 years old) with BMD T-score ≤ -2.0 (lumbar spine or femoral neck) were recruited from four clinical centers to receive low-dose (conventional dose) XLGB (L-XLGB group, 3 g/day, n = 61) or high-dose XLGB (H-XLGB group, 6 g/day, n = 58) or placebo (CON group, n = 61). Women received daily calcium (500 mg) and vitamin D (200 IU) supplementation. Primary endpoints were lumbar spine BMD and safety; secondary endpoints were femoral neck BMD and bone turnover markers measured at baseline and at 6 and 12 months. RESULTS Of 180 women recruited, 148 completed the study. The compliance in each group was comparable. Prominent adverse events were not observed in either group. In the L-XLGB group at 6 months, lumbar spine BMD by DXA increased significantly from baseline (+2.11% versus CON +0.58%, p < 0.05), but femoral neck BMD did not; at 12 months, BMD in the L-XLGB group decreased from 6-month levels yet remained higher than baseline, but without difference from the CON group. There was no dose-dependent response. Bone turnover marker levels declined during the first 6 months after XLGB treatment. There was no significant difference in the overall incidence of side effects among treatment and control groups. CONCLUSION XLGB over 1-year treatment at the conventional dose demonstrated safe and only a statistically significant increase in BMD at lumbar spine at 6 months in postmenopausal women.
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Affiliation(s)
- H M Zhu
- Centre of Osteoporosis, Shanghai Hua Dong Hospital, Fu Dan University, Shanghai, China.
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Gu G, Zhang Z, Wang G, Han F, Han L, Wang K, Liu J, Li W. Effects of electroacupuncture pretreatment on inflammatory response and acute kidney injury in endotoxaemic rats. J Int Med Res 2012; 39:1783-97. [PMID: 22117979 DOI: 10.1177/147323001103900521] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
This study investigated the effect of electroacupuncture pretreatment on the lipopolysaccharide (LPS)-induced inflammatory response and on acute kidney injury in adult male pathogen-free Wistar rats. Rats received electroacupuncture at the Zusanli (ST36) and Neiguan (PC6) acupoints, or electrical stimulation at sham points, for 30 min before stimulation with either 5 mg/kg LPS intravenously or normal saline. Plasma cytokines, plasma nitrite, renal inducible nitric oxide synthase (iNOS) and nuclear factor κB (NF-κB) activity were assessed 240 min after LPS or normal saline injection. Blood urea nitrogen (BUN), creatinine (Cr) and histopathological score for renal tubular damage were also measured. Electroacupuncture pretreatment significantly decreased LPS-induced plasma tumour necrosis factor-α and interleukin (IL)-1β, increased plasma IL-10, and decreased plasma nitrite, renal iNOS and NF-κB activity. It also significantly decreased LPS-induced BUN, Cr and the renal histopathological score. These findings suggest that electroacupuncture pretreatment at the ST36 and PC6 acupoints attenuated the LPS-induced inflammatory response and mitigated acute kidney injury.
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Affiliation(s)
- G Gu
- Department of Anaesthesiology, The Third Affiliated Hospital, Harbin Medical University, Harbin, China
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Gu G, Covington KR, Fernandez NM, Ando’ S, Fuqua SAW. P1-12-04: EBP50 – A Novel Biomarker for Resistance to Endocrine and HER2−Targeted Therapies in Breast Cancer. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-p1-12-04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Therapeutic strategies directed at inhibiting the action of ERa using antiestrogens, such as tamoxifen (Tam), or inhibiting HER2 signalling using a monoclonal antibody-Trastuzumab (Tras) are the standard therapies offered to women with ERa or ERa/HER2−positive cancer. However, not all patients respond to these targeted therapies, and a large number of patients who do respond will eventually develop disease progression or recurrence while on therapy. EBP50 functions as a molecular scaffold to coordinate a diverse range of regulatory processes and a number of studies suggest a role for EBP50 in cancer progression.
Material and Methods: Microarray profiling was used to identify genes associated with response to tamoxifen in primary as compared to metastatic breast tumor recurrences. Stable transfection of EBP50 shRNA was performed in ZR75B and BT-474 cells. Cell response to Tam and/or Tras was evaluated using soft agar and MTT growth assays. The molecular signaling pathways affected by EBP50 knockdown were explored using immunoblot, and immunoprecipitation. Cellular localization was determined using confocal microscopy. Mammosphere potential was used to evaluate the stem cell renewal capacity in BT-474 cells.
Results: The mean levels of EBP50 were reduced in the tamoxifen-resistant, metastatic breast tumors compared to tamoxifen-sensitive tumors. Knockdown of EBP50 levels decreased Tam sensitivity in ZR75B cells. Thus reduction in EBP50 levels analygous to that discovered in resistant patients, conferred resistance to the growth inhibitory effects of Tam. Cells with knockdown of EBP50 (shEBP50 cells) showed higher levels of phosphorylated HER2, EGFR and HER3, as well as their downstream signalling pathways. PI3K and AKT inhibitors were able to restore Tam sensitivity in shEBP50 cells. After long term treatment of ZR75-B cells with Tam resulted in decreased endogenous levels of EBP50, suggesting that only cells evolving with lower EBP50 levels were able to survive Tam treatment. Similarly, knockdown EBP50 in ERa/HER2 positive BT-474 cells significantly increased phosphorylated HER2 and these cells were resistant not only to Tam, but also to Tras treatment. BT-474 cells acquired Tras resistance concomittant with decreased EBP50 levels in a dose-dependent manner respective to parental cells. Interestingly, shEBP50 cells demonstrated an enhanced capacity to form mammospheres compared to vector control cells. We demonstrate that EBP50 is able to bind HER2 using immunoprecipitation, suggesting that EBP50 interacts directly with HER2. Confocal microscope analysis demonstrated the colocalization of these two proteins. Inhibitors to c-Src, PI3K, AKT and EGFR were used in combination with Tras; shEBP50 cells were sensitive to both PI3K and AKT inhibitors, and EGFR inhibitors were able to restore Tras sensitivity.
Discussion: Our data suggest that EBP50 is a novel negative regulator of HER2 signaling, and its loss conferred resistance to both Tam and Tras. EBP50 loss might function to stabilize HER2, and enhance dimerization with EGFR and HER3. We hypothesize that EBP50 levels might be a new predictive biomarker for targeted therapy; patients with low EBP50 levels might best be treated with a combination of therapies including PI3K/AKT inhibitors.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-12-04.
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Affiliation(s)
- G Gu
- 1Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - KR Covington
- 1Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - NM Fernandez
- 1Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - S Ando’
- 1Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - SAW Fuqua
- 1Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
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Brusco L, Barone I, Gu G, Beyer A, Fuqua SAW. Abstract P5-06-02: Loss of Rho GDIa Function and Tamoxifen Resistance in ERa-Positive Breast Cancer Cells. Cancer Res 2010. [DOI: 10.1158/0008-5472.sabcs10-p5-06-02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: We have previously shown that increased phosphorylation of the S305 site in ERa via mutation of ERa can lead to tamoxifen (Tam) resistance. We have also discovered that shRNA knockdown of the Rho disassociation inhibitor (Rho GDIa) can render estrogen receptor (ERa)- positive breast cancer cells more aggressive via an increase in their metastatic ability. Rho GDIa is a negative regulator of the Rho family of proteins, which play an important role in the regulation of the actin cytoskeleton. While the Rho pathway is known to influence metastasis in breast and other types of cancers, it is unclear how this pathway impacts on Tam sensitivity. Since loss of Rho GDIa causes an increase in the activity of the downstream Rho proteins (Rho, Rac, and Cdc42), it is possible that increased activity of downstream Rho effectors may lead to Tam resistance through crosstalk with the ERa signaling pathway. Materials and Methods: Rho GDIa was stably silenced in MCF-7 cells using shRNA and its levels validated using Western blot analysis. Kinase assays were perfomed using GST-tagged ERa fragments to assess the effect of various kinases on ERa. ERE-luciferase reporter assays were used to look at ERa transactivation with estrogen and Tam treatment. In vitro-derived Tam-resistant cells were generated by culturing MCF-7 cells in Tam for >6 months.
Results: Knockdown of Rho GDIa in ER-positive breast cancer cells resulted in Tam-resistant growth in vivo. Tam stimulated primary tumor growth in athymic nude mice. Mice injected with Rho GDIa knockdown cells exhibited metastatic lesions to the lung when treated with either estrogen or Tam. No lung tumors were detected in vector control transfected MCF-7 cells. Rhotekin pulldown assays revealed that Rho (A, B, and C), Rac1, and Cdc42 had higher activity in the Rho GDIa knockdown cells as compared to vector control cells. Immunecomplex kinase assays revealed that PAK1, a known downstream effector of the Rho pathway, exhibited increased activation in the Rho GDIa knockdown cells, and that this increased activity led to increased phosphorylation of ERa on the S305 residue. As expected, the acetylation of ERa was decreased when S305 was phosphorylated and this decrease in acetylation was dependent on phosphorylation of S305 since transfection of a plasmid containing a S305A mutation did not display decreased acetylation. ERE-luciferase assays showed that Rho GDIa knockdown cells had higher levels of estrogen and tamoxifen-induced activity in Rho GDIa knockdown cells as compared to vector control cells. Further possible effectors of Rho GDIa are being investigated as possible candidates playing roles in the crosstalk between these two pathways. Interestingly, cells which became Tam-resistant due to long term culture in the presence of Tam, also exhibited a decrease in endogenous Rho GDIa levels.
Discussion: Loss of Rho GDIa in ERa-positive breast cancer cells conferred a Tam-resistant and metastatic phenotype. Cells with decreased Rho GDIa levels displayed increased phosphorylation of ERa, suggesting that there is a level of crosstalk between the Rho family of signaling entwork and the ERa signaling pathway. We hypothesize that disruption of this crosstalk may be an approach to prevent or reverse Tam resistance in patients.
Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-06-02.
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Affiliation(s)
- L Brusco
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - I Barone
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - G Gu
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - A Beyer
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - SAW. Fuqua
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
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Gu G, Covington KR, Fernandez NM, Ando S, Fuqua SAW. Abstract P5-06-14: Ezrin Binding Protein Ebp50 Negatively Regulates HER2 and Alters Tamoxifen Sensitivity. Cancer Res 2010. [DOI: 10.1158/0008-5472.sabcs10-p5-06-14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Targeted therapy with antiestrogens and aromatase inhibitors are the mainstay of treatment for estrogen receptor (ER) a-positive breast cancer; however, resistance to these therapies ultimately occurs and patients recur with resistant disease.
Materials and Methods: Stable overexpression of a shRNA to Ebp50 or full-length Ebp50 was performed in MCF-7 breast cancer cells. Cell responsiveness to tamoxifen (Tam) was evaluated using soft agar and MTT growth assays. The molecular signaling pathways affected by Ebp50 knockdown were explored using immunoblot analysis, and immunoprecipitation assays. Cellular localization was determined using confocal microscopy.
Results: Modulation of Ebp50 levels altered cellular response to Tam treatment. Overexpression enhanced Tam sensitivity, whereas knockdown decreased Tam sensitivity. Thus reduction in Ebp50 levels analygous to that discovered in resistant patients, conferred resistance to the growth inhibitory effects of Tam. Since it is known that Ebp50 can bind to a number of cell surface receptors, we performed binding assays, and found that Ebp50 was able to bind to HER-2 in MCF-7 cells. In addition, this interaction was enhanced with Tam treatment. Enhanced activation of phospho-HER2 and total-HER2 levels, as well as pAKT were seen in the Ebp50 knockdown cells. We expressed deletion mutants of Ebp50 we saw increased levels of cytoplasmic ERa when the ERM domain was deleted. The ERM domain, which is know to be important for the binding cytoplasmic proteins, may thus be a determinant of ERa localization. Ebp50 was also shown to affect ERa transcriptional activity. Discussion: Our data suggest that Ebp50 may be a negative regulator of HER2 signaling, and its loss confered homrone resistance. Ebp50 loss might function to stabilize HER2 levels.
Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-06-14.
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Affiliation(s)
- G Gu
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - KR Covington
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - NM Fernandez
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - S Ando
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - SAW. Fuqua
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
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Vitek W, Pagidas K, Gu G, Pepperell J, Tantravahi U, Plante B. X-autosomal translocation — a distraction or a cause of primary ovarian insufficiency? Fertil Steril 2010. [DOI: 10.1016/j.fertnstert.2010.07.492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Korzeniewski SJ, Grigorescu V, Copeland G, Gu G, Thoburn KK, Rogers JD, Young WI. Methodological innovations in data gathering: newborn screening linkage with live births records, Michigan, 1/2007-3/2008. Matern Child Health J 2009; 14:360-4. [PMID: 19353254 DOI: 10.1007/s10995-009-0464-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2008] [Accepted: 03/13/2009] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To match Michigan birth and newborn screening records to identify and follow-up potentially unscreened infants, assess data quality, and demonstrate the utility of Link Plus linkage software for matching MCH related administrative datasets. METHODS Birth and newborn screening records maintained by the Michigan Department of Community Health from January 2007 through March 2008 were used in this study. Link Plus, a freely-available probabilistic record linkage software program developed at the Centers for Disease Control and Prevention, was used to match records. Linkage performance was assessed by the linkage success rate (percentage of valid matches). Follow-up of un-matched records was conducted by the Michigan Newborn Screening Follow-up Program. RESULTS Nearly all (99.2%) of the 142,178 birth records included in this study were successfully matched to newborn screening records. Following a transition to a web-based electronic birth certificate system and inclusion of a newborn screening card identification number on the birth record in 2008, the linkage success rate increased to 99.6% based on analysis of approximately 18,000 records. Of approximately 600 un-matched records, nearly half had received a newborn screen. Approximately 8% of un-matched records were due to parental refusal of newborn screening. Nine children received an initial screen as a result of this study; one was confirmed as having sickle cell trait. CONCLUSIONS We have demonstrated that a freely available record linkage software, Link Plus, can be used to successfully match records of MCH databases thereby providing an opportunity for further research and quality assurance investigations.
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Affiliation(s)
- S J Korzeniewski
- Division of Genomics, Perinatal Health and Chronic Disease Epidemiology Bureau of Epidemiology, Michigan Department of Community Health, 201 Capital View, 4-012, Lansing, MI 48906, USA.
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Tranquada J, Gu G, Huecker M, Xu G, Fujita M, Yamada K. Exploring the phase diagram of La 2−xBa xCuO 4: spins, stripes, and superconductivity. Acta Crystallogr A 2008. [DOI: 10.1107/s010876730809898x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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45
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Nazarian A, Gu G, Gracias NG, Wilkinson K, Hua XY, Vasko MR, Yaksh TL. Spinal N-methyl-D-aspartate receptors and nociception-evoked release of primary afferent substance P. Neuroscience 2008; 152:119-27. [PMID: 18222611 DOI: 10.1016/j.neuroscience.2007.11.037] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Revised: 11/13/2007] [Accepted: 11/28/2007] [Indexed: 11/26/2022]
Abstract
Dorsal horn N-methyl-D-aspartate (NMDA) receptors contribute significantly to spinal nociceptive processing through an effect postsynaptic to non-primary glutamatergic axons, and perhaps presynaptic to the primary afferent terminals. The present study sought to examine the regulatory effects of NMDA receptors on primary afferent release of substance P (SP), as measured by neurokinin 1 receptor (NK1r) internalization in the spinal dorsal horn of rats. The effects of intrathecal NMDA alone or in combination with D-serine (a glycine site agonist) were initially examined on basal levels of NK1r internalization. NMDA alone or when co-administered with D-serine failed to induce NK1r internalization, whereas activation of spinal TRPV1 receptors by capsaicin resulted in a notable NK1r internalization. To determine whether NMDA receptor activation could potentiate NK1r internalization or pain behavior induced by a peripheral noxious stimulus, intrathecal NMDA was given prior to an intraplantar injection of formalin. NMDA did not alter the formalin-induced NK1r internalization nor did it enhance the formalin paw flinching behavior. To further characterize the effects of presynaptic NMDA receptors, the NMDA antagonists DL-2-amino-5-phosphonopentanoic acid (AP-5) and MK-801 were intrathecally administered to assess their regulatory effects on formalin-induced NK1r internalization and pain behavior. AP-5 had no effect on formalin-induced NK1r internalization, whereas MK-801 produced only a modest reduction. Both antagonists, however, reduced the formalin paw flinching behavior. In subsequent in vitro experiments, perfusion of NMDA in spinal cord slice preparations did not evoke basal release of SP or calcitonin gene-related peptide (CGRP). Likewise, perfusion of NMDA did not enhance capsaicin-evoked release of the two peptides. These results suggest that presynaptic NMDA receptors in the spinal cord play little if any role on the primary afferent release of SP.
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Affiliation(s)
- A Nazarian
- Department of Anesthesiology, University of California-San Diego, La Jolla, CA 92093, USA.
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46
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Abstract
Glucocorticoid-induced osteoporosis may be at least in part due to the increased apoptosis of osteocytes. To study the role of osteocyte apoptosis in glucocorticoid-induced osteoporosis, we isolated primary osteocytes from murine calvaria for the analysis of the effects of dexamethasone in in vitro culture. The cells were identified by morphology, cytochemical staining, immunocytochemical staining and mRNA expression of phosphate-regulating gene with homology to endopeptidases on the X chromosome (PHEX) and sclerosteosis/van Buchem disease gene (SOST). We found that dexamethasone induced osteocyte apoptosis in a dose-dependent manner. A glucocorticoid receptor antagonist, mifepristone (RU486), suppressed dexamethasone-induced osteocyte apoptosis, suggesting that it was mediated by glucocorticoid receptor. Immunocytochemical stainings showed that glucocorticoid receptors are present in primary osteocytes, and they were translocated to nuclei after the exposure to dexamethasone. Addition of estrogen prevented glucocorticoid receptor translocation into nuclei. Corresponding antiapoptotic effects in primary osteocytes were also seen after the pretreatment of primary osteocytes with a picomolar concentration of estrogen. The pure antiestrogen ICI 182,780 inhibited estrogen effect on apoptosis induced by dexamethasone. These data suggest that glucocorticoid receptors play an important role in glucocorticoid-induced osteocyte apoptosis. Most importantly, estrogen has a protective effect against osteocyte apoptosis. To conclude, the mechanism of glucocorticoid-induced osteoporosis may be due to the apoptosis of osteocytes, which can be opposed by estrogen.
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Affiliation(s)
- G Gu
- Department of Anatomy, Institute of Biomedicine, University of Turku, Turku, Finland
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47
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Hua XY, Salgado KF, Gu G, Fitzsimmons B, Kondo I, Bartfai T, Yaksh TL. Mechanisms of antinociception of spinal galanin: how does galanin inhibit spinal sensitization? Neuropeptides 2005; 39:211-6. [PMID: 15944014 DOI: 10.1016/j.npep.2004.12.024] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2004] [Accepted: 12/02/2004] [Indexed: 11/30/2022]
Abstract
Galanin by a spinal action has been shown to have an antihyperalgesic action. Thus, in rats with lumbar intrathecal (IT) catheters, the thermal hyperalgesia evoked by carrageenan paw injection was blocked by IT delivery of galanin(1-29) (Gal(1-29)) and galanin(2-11) (Gal(2-11)) with the rank order of activity being Gal(1-29)>Gal(2-11). We sought to determine whether this spinal action reflects an effect upon afferent transmitter release, e.g., substance P (SP), and/or on secondary neurons, e.g., signaling postsynaptic to neurokinin 1 (NK1) receptor activation. To address the question on afferent release, we investigated the effect of IT administration of galanin on tissue injury-induced spinal NK1 internalization (an indicator of SP release). Noxious stimulation (paw compression) produced an increase in NK1 internalization in dorsal horn lamina I. IT pretreatment of rats with Gal(1-29) and Gal(2-11) significantly attenuated the evoked NK1 internalization, with the rank order of activity being Gal(1-29)>Gal(2-11)>saline. To address the question of postsynaptic action, we examined the effects of IT galanin upon IT SP-induced thermal hyperalgesia and spinal PGE2 release. Application of SP (30 nmol) directly to spinal cord led to a decrease in thermal thresholds and a profound increase in PGE(2) concentration in spinal dialysates. Both phenomena were reversed by Gal(1-29) and Gal(2-11) (10nmol, IT). These findings suggest that the antihyperalgesic effect of spinal galanin is due to its action on sites both presynaptic (inhibition of SP release) and postsynaptic (blockade of SP-evoked hyperalgesia and PGE2 production) to the primary afferents.
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Affiliation(s)
- X-Y Hua
- Anesthesia Research Laboratory, Department of Anesthesiology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0818, USA.
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Polston EK, Gu G, Simerly RB. Neurons in the principal nucleus of the bed nuclei of the stria terminalis provide a sexually dimorphic GABAergic input to the anteroventral periventricular nucleus of the hypothalamus. Neuroscience 2004; 123:793-803. [PMID: 14706792 DOI: 10.1016/j.neuroscience.2003.09.034] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Neurons of the principal nucleus of the bed nuclei of the stria terminalis (BSTp) process pheromonal and viscerosensory stimuli associated with reproduction and relay this information to preoptic and hypothalamic cell groups that regulate reproductive function. The anteroventral periventricular nucleus of the hypothalamus (AVPV), a nucleus involved in the regulation of gonadotropin secretory patterns, receives dense projections from BSTp neurons in males but not in females. By injecting the anterograde tracer, Phaseolus vulgaris leucoagglutinin (PHAL), into the BSTp of rats and immunohistochemically colocalizing the GABA synthetic enzyme, GAD65, to PHAL-immunoreactive fibers in the AVPV, we tested the hypothesis that these sex-specific projections arise from BSTp neurons that synthesize the inhibitory neurotransmitter GABA. Although dense GAD65-immunoreactive fiber terminals were observed in both the male and female AVPV, higher numbers of GAD65-labeled terminals were found in the male, and those localized to PHAL-immunoreactive fibers were seen almost exclusively in males. Treatment of newborn females with testosterone or neonatal orchidectomy of males reversed these sex differences, while GAD65-immunoreactivity in the AVPV was not altered in response to exogenous hormone treatments administered to peripubertal animals. Our results suggest that projections from BSTp neurons constitute a stable, sex-specific GABAergic input to the AVPV that is patterned permanently by perinatal hormone exposure.
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Affiliation(s)
- E K Polston
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, 97006, Beaverton, OR, USA
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Wang Y, Ono S, Onose Y, Gu G, Ando Y, Tokura Y, Uchida S, Ong NP. Dependence of upper critical field and pairing strength on doping in cuprates. Science 2003; 299:86-9. [PMID: 12511645 DOI: 10.1126/science.1078422] [Citation(s) in RCA: 171] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
We have determined the upper critical field Hc2 as a function of hole concentration in bismuth-based cuprates by measuring the voltage induced by vortex flow in a driving temperature gradient (the Nernst effect), in magnetic fields up to 45 tesla. We found that Hc2 decreased steeply as doping increased, in both single and bilayer cuprates. This relationship implies that the Cooper pairing potential displays a trend opposite to that of the superfluid density versus doping. The coherence length of the pairs xi(0) closely tracks the gap measured by photoemission. We discuss implications for understanding the doping dependence of the critical temperature Tc0.
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Affiliation(s)
- Yayu Wang
- Department of Physics, Princeton University, Princeton, NJ 08544, USA
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50
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Zhu Y, Moodenbaugh AR, Schneider G, Davenport JW, Vogt T, Li Q, Gu G, Fischer DA, Tafto J. Unraveling the symmetry of the hole states near the Fermi level in the MgB2 superconductor. Phys Rev Lett 2002; 88:247002. [PMID: 12059323 DOI: 10.1103/physrevlett.88.247002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2001] [Indexed: 05/23/2023]
Abstract
We use x-ray absorption spectroscopy (XAS) and electron energy loss spectroscopy (EELS) to study the fine structure at the K edge of boron in MgB(2). We observe in XAS a peak of width 0.7 eV at the edge threshold, signaling a narrow energy region with empty boron p states near the Fermi level. The changes in the near edge structure observed in EELS with direction of the momentum transfer imply that these states have p(x)p(y) symmetry. Our observations are consistent with electronic structure calculations indicating a narrow energy window of empty p(x)p(y) states that falls to zero at 0.8 eV above the Fermi level. The disappearance of the p(x)p(y) feature in EELS at grain boundaries suggests that this signature may become powerful in probing superconductivity at nanoscale.
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Affiliation(s)
- Y Zhu
- Brookhaven National Laboratory, Upton, NY 11973, USA
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