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Interstitial macrophages are a focus of viral takeover and inflammation in COVID-19 initiation in human lung. J Exp Med 2024; 221:e20232192. [PMID: 38597954 PMCID: PMC11009983 DOI: 10.1084/jem.20232192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 02/09/2024] [Accepted: 03/04/2024] [Indexed: 04/11/2024] Open
Abstract
Early stages of deadly respiratory diseases including COVID-19 are challenging to elucidate in humans. Here, we define cellular tropism and transcriptomic effects of SARS-CoV-2 virus by productively infecting healthy human lung tissue and using scRNA-seq to reconstruct the transcriptional program in "infection pseudotime" for individual lung cell types. SARS-CoV-2 predominantly infected activated interstitial macrophages (IMs), which can accumulate thousands of viral RNA molecules, taking over 60% of the cell transcriptome and forming dense viral RNA bodies while inducing host profibrotic (TGFB1, SPP1) and inflammatory (early interferon response, CCL2/7/8/13, CXCL10, and IL6/10) programs and destroying host cell architecture. Infected alveolar macrophages (AMs) showed none of these extreme responses. Spike-dependent viral entry into AMs used ACE2 and Sialoadhesin/CD169, whereas IM entry used DC-SIGN/CD209. These results identify activated IMs as a prominent site of viral takeover, the focus of inflammation and fibrosis, and suggest targeting CD209 to prevent early pathology in COVID-19 pneumonia. This approach can be generalized to any human lung infection and to evaluate therapeutics.
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Lineage-tracing hematopoietic stem cell origins in vivo to efficiently make human HLF+ HOXA+ hematopoietic progenitors from pluripotent stem cells. Dev Cell 2024; 59:1110-1131.e22. [PMID: 38569552 PMCID: PMC11072092 DOI: 10.1016/j.devcel.2024.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 12/05/2023] [Accepted: 03/01/2024] [Indexed: 04/05/2024]
Abstract
The developmental origin of blood-forming hematopoietic stem cells (HSCs) is a longstanding question. Here, our non-invasive genetic lineage tracing in mouse embryos pinpoints that artery endothelial cells generate HSCs. Arteries are transiently competent to generate HSCs for 2.5 days (∼E8.5-E11) but subsequently cease, delimiting a narrow time frame for HSC formation in vivo. Guided by the arterial origins of blood, we efficiently and rapidly differentiate human pluripotent stem cells (hPSCs) into posterior primitive streak, lateral mesoderm, artery endothelium, hemogenic endothelium, and >90% pure hematopoietic progenitors within 10 days. hPSC-derived hematopoietic progenitors generate T, B, NK, erythroid, and myeloid cells in vitro and, critically, express hallmark HSC transcription factors HLF and HOXA5-HOXA10, which were previously challenging to upregulate. We differentiated hPSCs into highly enriched HLF+ HOXA+ hematopoietic progenitors with near-stoichiometric efficiency by blocking formation of unwanted lineages at each differentiation step. hPSC-derived HLF+ HOXA+ hematopoietic progenitors could avail both basic research and cellular therapies.
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Prospective isolation of neural stem and progenitor cells from the developing human brain. STAR Protoc 2023; 4:102674. [PMID: 37897731 PMCID: PMC10751551 DOI: 10.1016/j.xpro.2023.102674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 09/02/2023] [Accepted: 10/05/2023] [Indexed: 10/30/2023] Open
Abstract
Prospective isolation of defined cell types is critical for the functional study of stem cells, especially in primary human tissues. Here, we present a protocol for purifying 10 transcriptomically and functionally distinct neural stem and progenitor cell types from the developing human brain using fluorescence-activated cell sorting. We describe steps for tissue dissociation, staining, and cell sorting as well as downstream functional experiments for measuring clonogenicity, differentiation, and engraftment potential of purified populations. For complete details on the use and execution of this protocol, please refer to Liu et al. (2023).1.
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Purification and characterization of human neural stem and progenitor cells. Cell 2023; 186:1179-1194.e15. [PMID: 36931245 PMCID: PMC10409303 DOI: 10.1016/j.cell.2023.02.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 11/06/2022] [Accepted: 02/10/2023] [Indexed: 03/18/2023]
Abstract
The human brain undergoes rapid development at mid-gestation from a pool of neural stem and progenitor cells (NSPCs) that give rise to the neurons, oligodendrocytes, and astrocytes of the mature brain. Functional study of these cell types has been hampered by a lack of precise purification methods. We describe a method for prospectively isolating ten distinct NSPC types from the developing human brain using cell-surface markers. CD24-THY1-/lo cells were enriched for radial glia, which robustly engrafted and differentiated into all three neural lineages in the mouse brain. THY1hi cells marked unipotent oligodendrocyte precursors committed to an oligodendroglial fate, and CD24+THY1-/lo cells marked committed excitatory and inhibitory neuronal lineages. Notably, we identify and functionally characterize a transcriptomically distinct THY1hiEGFRhiPDGFRA- bipotent glial progenitor cell (GPC), which is lineage-restricted to astrocytes and oligodendrocytes, but not to neurons. Our study provides a framework for the functional study of distinct cell types in human neurodevelopment.
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Mesenchymal stromal cells for the treatment of Alzheimer’s disease: Strategies and limitations. Front Mol Neurosci 2022; 15:1011225. [PMID: 36277497 PMCID: PMC9584646 DOI: 10.3389/fnmol.2022.1011225] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 09/20/2022] [Indexed: 11/27/2022] Open
Abstract
Alzheimer’s disease (AD) is a major cause of age-related dementia and is characterized by progressive brain damage that gradually destroys memory and the ability to learn, which ultimately leads to the decline of a patient’s ability to perform daily activities. Although some of the pharmacological treatments of AD are available for symptomatic relief, they are not able to limit the progression of AD and have several side effects. Mesenchymal stem/stromal cells (MSCs) could be a potential therapeutic option for treating AD due to their immunomodulatory, anti-inflammatory, regenerative, antioxidant, anti-apoptotic, and neuroprotective effects. MSCs not only secret neuroprotective and anti-inflammatory factors to promote the survival of neurons, but they also transfer functional mitochondria and miRNAs to boost their bioenergetic profile as well as improve microglial clearance of accumulated protein aggregates. This review focuses on different clinical and preclinical studies using MSC as a therapy for treating AD, their outcomes, limitations and the strategies to potentiate their clinical translation.
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LCOR mediates interferon-independent tumor immunogenicity and responsiveness to immune-checkpoint blockade in triple-negative breast cancer. NATURE CANCER 2022; 3:355-370. [PMID: 35301507 DOI: 10.1038/s43018-022-00339-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 01/21/2022] [Indexed: 01/05/2023]
Abstract
Ligand-dependent corepressor (LCOR) mediates normal and malignant breast stem cell differentiation. Cancer stem cells (CSCs) generate phenotypic heterogeneity and drive therapy resistance, yet their role in immunotherapy is poorly understood. Here we show that immune-checkpoint blockade (ICB) therapy selects for LCORlow CSCs with reduced antigen processing/presentation machinery (APM) driving immune escape and ICB resistance in triple-negative breast cancer (TNBC). We unveil an unexpected function of LCOR as a master transcriptional activator of APM genes binding to IFN-stimulated response elements (ISREs) in an IFN signaling-independent manner. Through genetic modification of LCOR expression, we demonstrate its central role in modulation of tumor immunogenicity and ICB responsiveness. In TNBC, LCOR associates with ICB clinical response. Importantly, extracellular vesicle (EV) Lcor-messenger RNA therapy in combination with anti-PD-L1 overcame resistance and eradicated breast cancer metastasis in preclinical models. Collectively, these data support LCOR as a promising target for enhancement of ICB efficacy in TNBC, by boosting of tumor APM independently of IFN.
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A Clinical PET Imaging Tracer ([ 18F]DASA-23) to Monitor Pyruvate Kinase M2-Induced Glycolytic Reprogramming in Glioblastoma. Clin Cancer Res 2021; 27:6467-6478. [PMID: 34475101 PMCID: PMC8639752 DOI: 10.1158/1078-0432.ccr-21-0544] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 07/15/2021] [Accepted: 08/30/2021] [Indexed: 01/10/2023]
Abstract
PURPOSE Pyruvate kinase M2 (PKM2) catalyzes the final step in glycolysis, a key process of cancer metabolism. PKM2 is preferentially expressed by glioblastoma (GBM) cells with minimal expression in healthy brain. We describe the development, validation, and translation of a novel PET tracer to study PKM2 in GBM. We evaluated 1-((2-fluoro-6-[18F]fluorophenyl)sulfonyl)-4-((4-methoxyphenyl)sulfonyl)piperazine ([18F]DASA-23) in cell culture, mouse models of GBM, healthy human volunteers, and patients with GBM. EXPERIMENTAL DESIGN [18F]DASA-23 was synthesized with a molar activity of 100.47 ± 29.58 GBq/μmol and radiochemical purity >95%. We performed initial testing of [18F]DASA-23 in GBM cell culture and human GBM xenografts implanted orthotopically into mice. Next, we produced [18F]DASA-23 under FDA oversight, and evaluated it in healthy volunteers and a pilot cohort of patients with glioma. RESULTS In mouse imaging studies, [18F]DASA-23 clearly delineated the U87 GBM from surrounding healthy brain tissue and had a tumor-to-brain ratio of 3.6 ± 0.5. In human volunteers, [18F]DASA-23 crossed the intact blood-brain barrier and was rapidly cleared. In patients with GBM, [18F]DASA-23 successfully outlined tumors visible on contrast-enhanced MRI. The uptake of [18F]DASA-23 was markedly elevated in GBMs compared with normal brain, and it identified a metabolic nonresponder within 1 week of treatment initiation. CONCLUSIONS We developed and translated [18F]DASA-23 as a new tracer that demonstrated the visualization of aberrantly expressed PKM2 for the first time in human subjects. These results warrant further clinical evaluation of [18F]DASA-23 to assess its utility for imaging therapy-induced normalization of aberrant cancer metabolism.
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[Eltrombopag for thrombocytopenia in 24 children after hematopoietic stem cell transplantation]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2021; 59:311-315. [PMID: 33775051 DOI: 10.3760/cma.j.cn112140-20200715-00727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To evaluate the efficacy and safety of eltrombopag for children with thrombocytopenia after hematopoietic stem cell transplantation (HSCT). Methods: Clinical data of 24 patients with thrombocytopenia after HSCT,who were treated with eltrombopag in the Department of Pediatrics, Sun Yat-sen Memorial Hospital, Sun Yat-sen University from August 1, 2018 to April 1, 2019 were analyzed retrospectively. The response rate and adverse reactions of eltrombopag were evaluated. Patients were divided into groups by source of hematopoietic stem cells (umbilical cord blood group and peripheral stem cell group) and type of disease (malignant and non-malignant disease group) and the clinical outcomes between groups were compared. Rank Sum test was used for comparisons between groups. Results: Among 24 cases, 15 were males and 9 females, the age of starting eltrombopag was 7.7 (2.6-13.7) years, the time of eltrombopag treatment after HSCT was 27.5 (8.0-125.0) days, the time from treatment to complete response (CR) was 23.5 (6.0-83.0) days, with the treatment course 36.5 (8.0-90.0) days. The total dose of eltrombopag was 1 400(200-5 900) mg. Complete response rate was 92% (22/24),without eltrombopag related adverse reactions. Comparing with peripheral stem cell group (n=8), the course and total dose of eltrombopag in umbilical cord blood group (n=16) were significantly reduced(24.5 (8.0-81.0) vs. 65.5 (35.0-90.0) d, Z=-3.004, P=0.002; 900.0 (200.0-3 850.0) vs. 2 862.5 (1 175.0-5 900.0) mg, Z=-2.604, P=0.007), but no significant differences were found in the time from treatment to complete response, platelet count after 2 weeks of eltrombopag withdrawal or platelet count at the end point of follow-up (all P>0.05). Comparing malignant patients (n=12) and non-malignant patients (n=12), no significant differences were found in the time from treatment to complete response, course, total dose, platelet count after 2 weeks of eltrombopag withdrawal, and platelet count at the end point of follow-up in non-malignant patients (all P>0.05). Conclusion: Eltrombopag is safe and maybe effective for thrombocytopenia after HSCT, especially for umbilical cord blood transplantation.
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[Effect of comprehensive AIDS intervention among men aged 50 or over who had non-marital sexual behavior]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2020; 40:1595-1600. [PMID: 32062922 DOI: 10.3760/cma.j.issn.0254-6450.2019.12.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To evaluate the effectiveness of AIDS intervention programs on men aged 50 or over and having had non-marital sexual behavior. Methods: A community-based intervention/experimental and based on individual level study was adopted. Stratified sampling method was used. 12 townships/streets in Fuyang district of Hangzhou were identified as intervention or control group (six research sites each). All of the subjects in the township (street) were included. The inclusion criteria of study objects would include men aged 50 or older who reported having unmarried sex in the last year. Estimated sample size was 290, with each 145 in the intervention group and the control group. All the intervention group participants were provided with a total of 4 intervention-related items (knowledge and education on AIDS prevention, information radiation and behavioral change, broadcast expert lectures), every 3 months, for 12 month, the main evaluation indicators would include: incidence of non-marital sex and commercial sex in the last year, condom use when having non-marital sex in the last episode. Results: A total of 312 subjects were recruited. 300 of them completed the baseline study while 284 of them completed the follow-up survey. Among the subjects who had undergone the baseline study, the average age was (65.58±7.89), 71.33% were married or cohabiting with someone, 52.00% having had primary school education. After the implementation of intervention programs, the incidence of non-marital sex dropped to 59.42% (82/138) and the incidence of commercial sex dropped from 79.73% (118/148) to 55.07% (76/138). Condom use rate in the last non-marital sexual contact increased from 19.59% (29/148) to 51.22% (42/82). In the control group, the incidence of non-marital sex in the year before dropped to 74.66% (109/146) and the incidence of commercial sex dropped from 91.45% (139/152) to 72.60% (106/146). Rates of condom use during the last non-marital sexual contact dropped from 32.89% (50/152) to 31.19% (34/109). Statistically, there were significant differences appeared between the two groups on the incidence of non-marital sex in the past year (χ(2)=7.48, P=0.008), the incidence of commercial sex in the last year (χ(2)=9.47, P=0.003) and the rate of condom use in the last sex experience (χ(2)=7.83, P=0.007). Conclusions: Results from this intervention study showed that: in the intervention group, both the incidence rates of non-marital or commercial sex had reduced, together with the increase of condom use in non-marital sex in the last sexual experience. Intervention strategies that involving knowledge and education on AIDS prevention, information radiation and behavioral change, broadcasting lectures by experts etc. were all proved effective.
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[Safety evaluation on different ventilation strategies set for neonatal respiratory distress syndrome: a network Meta-analysis]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2020; 41:249-260. [PMID: 32164138 DOI: 10.3760/cma.j.issn.0254-6450.2020.02.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Objective: To evaluate the relative safety of different ventilation methods regarding mortality and rates of complication, on neonatal respiratory distress syndrome (NRDS). Methods: Network Meta-analysis was used to collect data on randomized controlled trials of pulmonary ventilation strategies in preterm infants with a mean gestational age of less than 32 weeks. Diagnostic criteria on NRDS were published in the PubMed, Cochrane, Web of Science, EBSCO, and Springer Link databases from January 1986 to June 2018. Revman 5.3 software was used to evaluate the quality of studies, based on the Cochrane quality assessment tool. Data were analyzed by Bayesian and frequency methods, using both Win BUGS 1.4.3 and STATA 13.0 software. Safety of different ventilation strategies for NRDS mortality and complications would include intraventricular hemorrhage (IVH), patent ductus arteriosus (PDA) and retinopathy of prematurity (ROP) and were evaluated. Counted data was displayed by OR and 95%CI. Results: A total of 31 RCTs were included in this paper, including 5 827 preterm infants and 11 ventilation strategies. There were no statistically significant differences appearing in 11 ventilation strategies on mortality, PDA or ROP. IVH results were reported in 28 studies. Compared with nasal intermittent positive pressure ventilation (NIPPV), both high- frequency oscillation ventilation (HFOV) (OR=3.33, 95%CI: 1.08-16.67, P<0.05) and synchronized intermittent mechanical ventilation (SIMV) (OR=8.22, 95%CI: 1.25-29.44, P<0.05) schemes seemed to have increased the risk of IVH in preterm infants with NRDS. NIPPV appeared the optimal ventilation strategy in the rankings of cumulative probability. Results on clustering showed that NIPPV was probably the best ventilation strategy for children with NRDS after considering the orders of IVH, PDA and ROP on mortality, respectively. However, HFOV, IMV, and SIMV did not seem to be the ideal ventilated strategies. Conclusions: Most of the clinical decision makers might prefer using NIPPV in the treatment of children with NRDS through mechanical ventilation systems to reduce both the incidence and death caused by IVH, PDA and ROP. It was not recommended to use HFOV, SIMV and IMV in treating NRDS with gestational less than 32 weeks. We suggested that larger numbers of multi-center RCTs ba carried out to make the above conclusions more convincing.
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[The influence factors of quality-of-life in patients with thyroid-associated ophthalmopathy]. [ZHONGHUA YAN KE ZA ZHI] CHINESE JOURNAL OF OPHTHALMOLOGY 2019; 53:575-582. [PMID: 28851197 DOI: 10.3760/cma.j.issn.0412-4081.2017.08.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To assess the risk factors associated with decreased quality-of-life in patients with thyroid-associated ophthalmopathy (TAO). Methods: Cross-sectional study. One hundred and twelve patients with TAO and 68 controls were recruited to answer the Graves' ophthalmopathy quality-of-life questionnaire (GO-QOL) from January 2014 to April 2016. The GO-QOL included two subscales: the visual functioning and the psychosocial consequences. The differences in the GO-QOL scores between TAO patients and controls were analyzed. The influences of multiple factors on the GO-QOL scores among TAO patients were explored. Results: Among 112 TAO patients, 63 were male and 49 were female, with an average age of (45.4±13.1) years. Among 68 controls, 36 were male and 32 were female, with an average age of (39.5±10.8) years. Independent sample t test showed that TAO patients had significantly lower scores than controls in the visual functioning subscale and the psychosocial consequences subscale (55.63±29.02 vs 97.48±6.96, t=-14.58, P<0.01; 57.61±29.97 vs100±0.00, t=-14.97, P<0.01). Among TAO patients, smokers were associated with significantly lower psychological subscale scores than non-smokers (t=-2.284, P=0.024). Patients with abnormal primary position of eye scored significantly lower than those with normal alignment in functional (t=-3.979, P<0.001) and psychological subscales (t=-2.154, P=0.034) Patients with abnormal eye movement had significantly lower functional scores than those without (t=-2.975, P=0.004). One-way analysis of variance showed that higher CAS scores were significantly related to lower psychological subscale scores (F=3.178, P=0.018). Patients with upper eyelid retraction had significantly lower psychological subscale scores than those without (F=3.562, P=0.032). Pearson correlation analysis showed that age was negatively correlated with functional subscale scores (r=-0.366; P<0.01). TAO course was negatively correlated with functional (r=-0.235, P<0.05) and psychological subscale scores (r=-0.320, P<0.01). The degree of exophthalmos was negatively correlated with psychological subscale scores (r=-0.209, P<0.01). Multivariable linear regression analysis showed that only primary position of eye (P=0.013) and TAO course (P=0.007) were negatively correlated with functional subscale scores and only CAS scores (P=0.022) and TAO course (P=0.024) were negatively correlated with psychological subscale scores. Conclusion: Risk factors associated with lower quality-of-life among TAO patients included abnormal primary position of eye, higher CAS scores, and longer TAO course.(Chin J Ophthalmol,2017,53: 575-582).
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Abstract
1. The aim of the present study was to investigate the effects of different starch sources (corn, wheat, and rice) on the blood glucose level, glycogen content of liver and muscle, expression of GSK-3β and FAS mRNA, abdominal fat weight and abdominal fat deposition in broiler chickens. 2. A total of 360, one-day-old AA (Arbor Acres) broiler chickens were randomly assigned to three treatment groups, each with six replicates, consisting of 20 chickens per replicate, and fed either a corn-, wheat- or rice-based diet for 21 days. The chickens were then subdivided into groups A and B, and the chickens in these two subgroups were processed or sampled for 28 days, respectively. 3. The results indicated that post-prandial time significantly affected the glucose concentration, glycogen content in the liver and breast muscle and expression of GSK-3β and FAS mRNAs (P < 0.05). The expression of the GSK-3β gene in the chicken liver of the corn-based diet group was higher (P < 0.05) than that in the wheat-based diet group, and the expression of the FAS gene in the corn-based diet group was lower (P < 0.05) than that in the wheat-based and rice-based diet groups. Abdominal fat weight and deposition in the corn-based diet group were lower than those of the wheat-based and rice-based diet groups, but these differences were not significant (P > 0.05). 4. The results suggested that the efficiency of glucose absorption in animals might have an effect on the fat deposition efficiency in the liver and that diets with different starch sources might affect fat deposition in chickens.
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[Differences of brain functional alterations between subtypes of Cushing's syndrome patients]. ZHONGHUA YI XUE ZA ZHI 2019; 99:593-598. [PMID: 30818928 DOI: 10.3760/cma.j.issn.0376-2491.2019.08.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Objective: To compare the differences of brain functional damage of subtypes of patients with Cushing's syndrome (CS). Methods: A total of 11 adrenocorticotropic hormone (ACTH)-dependent CS patients and 29 ACTH-independent CS patients were recruited from Chinese PLA General Hospital between September 2015 and March 2017 with confirmed CS. The psychiatric scales and brain task functional magnetic resonance imaging (fMRI) were evaluated. Results: A total of 40 patients (34 females, 6 males) with a mean age of (39.20±12.10) years and a median education level of 12 (9, 16) years were enrolled. ACTH-dependent patients had significantly worse performance than the ACTH-independent patients in response to the depression evaluation (64.6±6.1 vs 56.2±12.8, P=0.008), positive emotion (17.8±4.2 vs 24.3±7.2, P=0.008) and CS life quality [31(29,33) vs 42(29,51), P=0.040]. In the reaction to positive target pictures, ACTH-dependent CS patients showed stronger activation in left superior temporal gyrus compared with patients in ACTH-independent group, while the activation degree of their bilateral dorsal anterior cingulate cortex, bilateralsuperior frontal gyrus and left middle frontal gyrus was much worse. In the reactions to negative target pictures, ACTH-dependent CS patients had weaker activation in bilateral cerebellum, left superior frontal gyrus, left middle frontal gyrus, left precuneus and right postcentral gyrus, compared with patients in the ACTH-independent CS group (P<0.01, AlphaSim corrected). The activation degree of some regions whose brain function was different between the two groups was correlated to the cortisol level, ACTH level, 24 h urinary free cortisol (UFC) level, depression evaluation and negative emotion assessment (all P<0.05). Conclusions: The severity of the depression and the life quality of patients in ACTH-dependent group are worse than ACTH-independent CS patients. The brain function of ACTH-dependent CS patients is much weaker.
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Abstract OT2-09-02: A phase I dose escalation study of topical bexarotene in women at high risk for breast cancer. Cancer Res 2019. [DOI: 10.1158/1538-7445.sabcs18-ot2-09-02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Breast cancer prevention with anti-estrogens, including tamoxifen, raloxifene, and exemestane, has been shown to reduce the incidence of hormone receptor-positive breast cancer. However, agents that can reduce the incidence of hormone receptor negative breast cancer are currently lacking. Rexinoids such as bexarotene are vitamin A analogues that have been shown to be involved in cell differentiation, growth, and apoptosis. In preclinical mouse models that develop ER-negative breast cancers, bexarotene showed a significant reduction in mammary tumor development. Oral bexarotene has been evaluated in BRCA mutation carriers and significant decreases in cyclin D1 were noted in breast cells suggesting biological activity of bexarotene on breast tissue. Systemic side effects of hyperlipidemia and hypothyroidism were also found. Data from chemoprevention studies with topical 4-hydroxytamoxifen support the concept of topical agents penetrating into the breast tissue and exhibiting biological activity in the tissue. We hypothesize that topical bexarotene can be applied to the breast as a chemoprevention agent with penetration to the breast tissue without subsequent systemic side effects and toxicity as seen with oral bexarotene.
Trial Design: Women at high risk for breast cancer will be recruited and assigned to one of three different dose levels: 10mg (1ml) every other day, 10mg (1ml) daily, 20mg (2ml) daily to one unaffected breast for 4 weeks. The primary endpoint of the study is to determine the recommended phase II dose of topical bexarotene 1% gel for evaluation in healthy at-risk women. Dose Limiting Toxicity (DLT) is defined as a grade 2 skin adverse event that persists for at least 6 days or any grade 3 or greater adverse event related to the study drug. A grade 2 skin adverse event that recurs and persists for at least 3 days is also a DLT. The Maximum Tolerated Dose (MTD) will be defined as the highest dose level at which no more than 2 participants experience a DLT among 10 participants treated. A conservative modification of the standard “3+3” design will be applied. The first three participants will be assigned to the lowest dose level. New cohorts of 3-4 participants will not be treated until toxicity has been fully evaluated for all current participants through 4 weeks. Once the MTD has been determined, an expansion cohort of an additional 10 patients will be recruited at the MTD to further evaluate safety and toxicity at this dose level as well bexarotene concentration in the breast tissue. Secondary endpoints include serum bexarotene level, tissue bexarotene levels, and changes in thyroid function tests, lipid profile, and calcium. The planned accrual for this study if maximally accrued to all dose levels and the dose expansion cohort will be 40 participants.
Citation Format: Thomas PS, Patel AB, Contreras A, Liu DD, Lee JJ, Khan S, Vornik LA, Dimond EP, Perloff M, Heckman-Stoddard BM, Brown PH. A phase I dose escalation study of topical bexarotene in women at high risk for breast cancer [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 OT2-09-02.
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Abstract P5-09-02: Clinical and pathological characteristics and screening outcome for secondary cancers of women with breast cancer and Li-Fraumeni syndrome. Cancer Res 2019. [DOI: 10.1158/1538-7445.sabcs18-p5-09-02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Germline TP53 mutations predispose to early onset breast cancer in women and are associated with Li-Fraumeni syndrome. Published data on the clinical and pathological characteristics and screening outcome for secondary cancers among women with breast cancer and TP53 mutations is limited. To the best of our knowledge this is the largest cohort of breast cancer associated with Li-Fraumeni syndrome.
Methods: Patients with breast cancer and Li-Fraumeni Syndrome were identified from a prospective research database from 2001 to 2017. Patients had genetic counselling and testing at The University of Texas MD Anderson Cancer Center and confirmed to have TP53 mutations associated with Li-Fraumeni syndrome. We reviewed the patient's charts to identify the clinical and pathological characteristics of their breast cancer. Data for secondary cancers are obtained only for patients with breast cancer as their initial cancer diagnosis and who are followed at The MD Anderson's Li-Fraumeni Education and Early Detection (LEAD) clinic which conducts comprehensive cancer screening for these patient's per the NCCN guidelines, including yearly whole body MRIs.
Results: Fifty-nine patients confirmed to have Li-Fraumeni syndrome and breast cancer (100% female, median age 30 years). 94% of the patients were pre-menopausal at the time of breast cancer diagnosis and 6% were post-menopausal due to bilateral salpingo-oophorectomy. 61% were diagnosed after abnormal self or clinical breast exam and 26% based on abnormal screening mammography or ultrasound. In terms of the histologic subtype of breast cancer: 69% had invasive ductal carcinoma, 5% mucinous carcinoma, 5% mixed ductal and lobular, 5% sarcoma, 3% phylloides tumor and 13% with missing data. Pathologic stage per the 7th edition of AJCC cancer staging system was as follows: 23% stage I, 26% stage II, 23% stage III, 28% remaining with unknown pathologic stage. Pathologic markers include: 70% with positive estrogen receptor expression, 64% with positive progesterone receptor expression, 57% with HER-2 amplification defined per the ASCO-CAP HER-2 test guidelines and 7% with triple negative disease. Forty three patients were followed at LEAD clinic. Of the 43 patients, 40% (N=17) were diagnosed with 1 primary cancer other than breast cancer, 7% (N=7) with 2 primary cancers other than breast cancer and 44% (N=19) with breast cancer only. Out of the 43 patients, 5 were diagnosed with acute myelogenous leukemia, 4 with leiomyosarcoma, 3 osteosarcoma, 4 with other types of sarcoma, 4 with central nervous cell tumors (astrocytoma or glioblastoma multiforme), 3 with papillary thyroid carcinoma, 1 with pancreatic cancer, 1 with renal cell carcinoma, 1 adrenocortical carcinoma, 1 with uterine cancer, 1 with melanoma and 1 with cervical cancer.
Conclusion: This study to our knowledge is the largest cohort of patient's with Li-Fraumeni syndrome and associated breast cancer that is followed in a dedicated clinic for patients with Li Fraumeni Syndrome. This cohort highlights the characteristics of patients with Li-Fraumeni syndrome and associated diagnosis of breast cancer as well as other primary cancers.
Citation Format: Al-Awadhi A, Liu DD, Gutierrez-Barrera AM, Strong LC, Arun BK. Clinical and pathological characteristics and screening outcome for secondary cancers of women with breast cancer and Li-Fraumeni syndrome [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 P5-09-02.
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Abstract P1-18-04: CTCs and SUV to predict the efficacy of the bone-specific radiopharmaceutical agent radium-223 dichloride combined with hormonal therapy for hormone receptor-positive bone-dominant breast cancer metastasis. Cancer Res 2019. [DOI: 10.1158/1538-7445.sabcs18-p1-18-04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Radium-223 dichloride (Ra-223) is a targeted alpha particle-based radiotherapeutic that has a localized cytotoxic effect on bone metastases. We sought to determine whether the circulating tumor cell (CTC) count and the presence of CTCs in epithelial-mesenchymal transition (EMT-CTCs) along with the standardized uptake value (SUV) on positron emission tomography-computed tomography (PET/CT) scans predict the efficacy of combined Ra-223 and hormonal therapy in patients with hormone receptor (HR)-positive bone-dominant metastatic breast cancer.
Patients and Methods: In this single-center phase 2 study (NCT02366130), 36 patients received Ra-223 (55 kBq/kg intravenously) on day 1 and then every 4 weeks for six cycles. Patients also received a standard care endocrine monotherapy. One non-bone metastatic site was allowed. The number of prior endocrine therapies was not limited and one prior chemotherapy was allowed for metastasis. Response was evaluated using the PET Response Criteria in Solid Tumors (PERCIST) with PET/CT at baseline, 6 and 9 months (mo) later. The CTC count (CellSearch) and the presence of EMT-CTCs (AdnaTest) was determined at baseline, 6 and 9 mo later. Progression-free survival (PFS) time was calculated to evaluate efficacy.
Results: Seven patients (20%) had a non-bone metastatic site. The median number of prior therapies for metastasis was 1 (range, 0-4). Six patients (17%) received chemotherapy. The median CTC count at baseline was 4 (range, 0-306). Only four patients (11%) were positive for EMT-CTCs at baseline. The median follow-up time was 14.7 mo (95% confidence interval [CI], 13.2 mo-not reached [NR]). The disease control rate at 9 mo was 46% in 33 patients who reached 9 mo or progressed up to 9 mo. The tumor response rate at 6 mo was 52% (complete/partialresponse rate; 22/30 %) in 27 patients whose disease was evaluable using PERCIST. The SUV on PET/CT decreased significantly at 6 and 9 mo after baseline (average decreases of 1.5 (p=0.0004) and 2.5 (p=0.0054), respectively). The median PFS duration was 7.4 mo (95% CI, 4.8 mo-NR). The median bone PFS was 16 mo (95% CI, 7.3 mo-NR). Patients with bone-only metastasis (N=28, 80%) had a significantly longer median PFS duration than did patients with non-bone metastases at baseline (N=7, 20%) (13.8 mo versus 4.5 mo; p=0.017). Patients without prior treatment (N=12, 34%) tended to have longer median PFS durations than did those who underwent prior treatment (N=23, 66%) (16.8 mo versus 4.8 mo; p=0.1865). Also, patients with <5 CTCs at baseline (N=19, 54%) tended to have longer median PFS durations than did those with ≥5 CTCs (N=16, 46%) (13.8 mo versus 4.8 mo; p=0.1277). EMT-CTCs status did not predict efficacy.
Conclusions: Bone-only metastatic breast cancer and SUV suppression by Ra-223 are predictive of efficacy. Patients with baseline <5 CTC count tended to have better outcomes than did those with ≥5 CTCs. Combined treatment with Ra-223 and a hormonal agent is especially effective at controlling bone metastasis in patients with HR-positive breast cancer. Bone-only metastatic disease and CTC count should be factored in future clinical trial designs.
Citation Format: Ueno NT, Tahara RK, Reuben JM, Gao H, Saigal B, Fujii T, Lucci A, Ibrahim NK, Damodaran S, Shen Y, Liu DD, Hortobagyi GN, Tripathy D, Lim B, Chasen BA. CTCs and SUV to predict the efficacy of the bone-specific radiopharmaceutical agent radium-223 dichloride combined with hormonal therapy for hormone receptor-positive bone-dominant breast cancer metastasis [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 P1-18-04.
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Abstract OT1-02-01: A phase II study of anti-PD-1 (MK-3475) therapy in patients with metastatic inflammatory breast cancer (MIBC) or non-IBC triple negative breast cancer (non-IBC TNBC) who have achieved clinical response or stable disease to prior chemotherapy. Cancer Res 2018. [DOI: 10.1158/1538-7445.sabcs17-ot1-02-01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Primary Objective: To assess the efficacy of MK-3475 as a single agent in patients with MIBC and non-IBC TNBC. The primary endpoint is disease control rate at the end of 4 months after receiving the treatment. We will also investigate the association between biomarkers in the peripheral blood and tumor tissue, safety and efficacy.
Background: The extensive invasion of lymphatic vessels by tumor emboli in patients with IBC suggests that the host immune surveillance system is suboptimal or that the tumor cells have decreased immunogenicity through immune editing to avoid detection by the host. In the immune-competent host, tumor cells must overcome both innate and adaptive immunologic defenses of the host. The PD-1 receptor-ligand interaction is a major pathway hijacked by tumors to suppress immune control. MK-3475 is a potent and highly selective humanized mAb designed to block the interaction between PD-1 and its ligands, PD-L1 and PD-L2. MK-3475 strongly enhances T lymphocyte immune responses in cultured blood cells from healthy human donors, cancer patients, and primates. Mouse anti-PD-1, as a monotherapy, demonstrated efficacy in several syngeneic mouse tumor models. To date, no specific targeted therapeutic options exist for the treatment of MIBC and TNBC. After patients achieving a clinical response to systemic therapy, the maintenance of disease control is not guaranteed. Further, our recent publication suggests that IBC has immune dysfunction. Chemotherapies can debulk the disease volume but cannot be used for maintenance due to their toxicities. Using an anti PD-1 monoclonal antibody is a promising approach for this patient population.
Study Design and Treatment Plan: This is a single arm phase II study. Up to 35 patients with HER2 negative MIBC or metastatic TN-IBC (MTNBC) who have achieved clinical response or stable disease after receiving any prior systemic therapy for metastatic/recurrent disease, and meet all other criteria will be eligible. Patients will receive MK-3475 200 mg IV every 3 weeks for up to 2 years.
Statistical Considerations: The trial will be conducted using Simon's optimal two-stage design and the rate of disease control will be estimated accordingly. It is assumed that the MK-3475 single agent will have a disease control rate of 30%. A disease control rate of 10% or lower will be considered treatment failure and the regimen will be rejected under this circumstance.
Status of the study:
Activation Date: June 2015. 13 patients have been enrolled. Enrollment continues.
Sponsor: Merck Sharp & Dohme Corp.
State of Texas appropriation for rare and aggressive breast cancer research.
Citation Format: Willey JS, Parker CA, Valero V, Lim B, Reuben JM, Krishnamurthy S, Gong Y, Scoggins ME, Dryden MJ, Liu DD, Woodward WA, Ueno NT. A phase II study of anti-PD-1 (MK-3475) therapy in patients with metastatic inflammatory breast cancer (MIBC) or non-IBC triple negative breast cancer (non-IBC TNBC) who have achieved clinical response or stable disease to prior chemotherapy [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 OT1-02-01.
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Abstract OT1-01-05: A phase II study using talimogene laherparepvec as a single agent for inflammatory breast cancer or non-inflammatory breast cancer patients with inoperable local recurrence. Cancer Res 2018. [DOI: 10.1158/1538-7445.sabcs17-ot1-01-05] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Objective: The primary purpose of the study is to determine the local and systemic antitumor efficacy of talimogene laherparepvec in locally recurrent breast cancer patients with or without distant metastases, as evidenced by improved overall response rates. This will be the first study to use biopsy of distant disease to demonstrate whether systemic immune modulation has antitumor efficacy in breast cancer patients.
BACKGROUND: Patients with locally recurrent breast disease frequently undergo multimodal treatment at the first occurrence of breast cancer, and because local treatment modalities such as surgical intervention and radiation are difficult to add, they subsequently receive systemic therapy. Talimogene laherparepvec (T-VEC) was developed to eliminate solid tumors and has since been considered as a potential treatment option for body surface tumors. In addition to T-VECinjected area, this agent is capable of modifying the immune response with the potential of inhibiting distant metastases. Hence, locally recurrent breast disease could benefit from T-VECregardless of concomitant distant metastases, and may offer a new local treatment option.
Study Design and Treatment Plan: This is a single agent phase II study. Patients with breast cancer who have recurrence of chest wall disease with or without distant metastasis, have at least 1 injectable lesion ≥5 mm in longest diameter or multiple injectable lesions that in aggregate have a longest diameter of ≥ 5 mm, and meet inclusion and exclusion criteria will be eligible to participate in the study. Patient will receive T-VEC via intra-tumoral injection every 2 weeks after the first initial injection (3 weeks).
STATISTICAL METHODS:
Up to 35 patients will be enrolled in the study. The trial will be conducted using a two-stage design and the overall response rate will be estimated accordingly. It is assumed that the talimogene laherparepvec single agent will have a response rate of 20%. A response rate of 5% or lower will be considered treatment failure and the regimen will be rejected under this circumstance.
Status of the study:
Activation Date: Aug 2016. 6 patients have been treated. Enrollment continues.
Sponsor: Amgen
State of Texas appropriation for rare and aggressive breast cancer research.
Citation Format: Willey JS, Marx AN, Lim B, Ibrahim NK, Valero V, Mittendorf EA, Reuben JM, Le-Petross HT, Whitman GJ, Krishnamurthy S, Woodward WA, Lucci A, Liu DD, Shen Y, Ueno NT. A phase II study using talimogene laherparepvec as a single agent for inflammatory breast cancer or non-inflammatory breast cancer patients with inoperable local recurrence [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 OT1-01-05.
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Abstract P1-16-02: Phase II study of the feasibility and safety of radium-223 dichloride in combination with hormonal therapy and denosumab for the treatment of patients with hormone receptor-positive breast cancer with bone-dominant metastasis. Cancer Res 2018. [DOI: 10.1158/1538-7445.sabcs17-p1-16-02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background
Radium-223 dichloride (Ra-223) is a therapeutic alpha particle-emitting radiopharmaceutical compound which have antitumor effect targeted on bone metastases. Alpha particles induces double strand DNA breaks and localized cytotoxic effect to cancer cells with limiting harm on normal tissues. We are conducting a phase II clinical trial of combination of Ra-223, hormonal therapy, and denosumab treatment in patients with hormone receptor (HR)-positive bone-dominant metastatic breast cancer (NCT02366130). In this preliminary analysis of the study, we aimed to evaluate the feasibility and safety of this combination therapy.
Methods
This single-center phase II study seeks to determine the efficacy and safety of Ra-223 in combination with hormonal therapy and denosumab. Major eligibility criteria include HR-positive breast cancer with bone and/or marrow predominant metastases. Patients with two or more visceral metastases were not eligible. There was no limit in the number of prior hormonal therapies in the metastatic setting. Patients received Ra-223 injection (55 kBq/kg intravenously) on day 1 of the study and then every 4 weeks thereafter for 6 cycles. Patients were also administered a single hormonal agent (i.e., tamoxifen, aromatase inhibitor, or fulvestrant at standard doses) daily and denosumab (120 mg subcutaneously) every 4 weeks. For this analysis, adverse events (AEs) were summarized using descriptive statistics.
Results
A total of 25 patients were enrolled and 22 were evaluable between March 2015 and December 2016. Median age was 58.5 years (range 31-79), and 59% of patients were postmenopausal. ECOG performance status was 0 in 16 patients (73%), and 1 in six patients (27%). HER2/neu was positive in only one patient. Four patients (18%) were de novo metastasis, no patients had visceral metastasis, and multiple bone metastases in 20 patients (91%) vs. focal metastasis in 2 (9%). Median time from diagnosis of bone metastasis was 4.8 months (range 0.5-96.6). Prior therapy for metastatic disease consisted of hormonal therapy in 50% of the patients (eight patients with one line and three patients with two lines), chemotherapy (9%), palbociclib (14%), radiation to bone metastasis (50%), and bone-supportive therapy (27% with zoledronic acid, 27% with denosumab). The median number of cycles of Ra-223 administered was 6 (range 4-6).
The median follow-up time was 4 months (range 2-8). There were no grade 3 or 4 AEs. Major non-hematological grade 1 and 2 AEs were bone pain (77%), fatigue (45%), nausea (36%), diarrhea (32%), AST/ALT elevation (23%), hot flashes (23%), and headache (18%). The most common hematological AEs were grade 1 or 2 neutropenia (23%), anemia (14%), and thrombocytopenia (18%). There was no treatment delay or discontinuation due to AEs.
Conclusion
Our results suggest that the addition of Ra-223 to hormonal therapy and denosumab is a feasible and safe combination therapy in patients with HR-positive breast cancer with bone-dominant metastasis. We continue to enroll patients in the phase II trial to evaluate the efficacy of the treatment.
Citation Format: Tahara RK, Fujii T, Saigal B, Ibrahim NK, Damodaran S, Barcenas CH, Murray JL, Chasen BA, Shen Y, Liu DD, Hortobagyi GN, Tripathy D, Ueno NT. Phase II study of the feasibility and safety of radium-223 dichloride in combination with hormonal therapy and denosumab for the treatment of patients with hormone receptor-positive breast cancer with bone-dominant metastasis [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 P1-16-02.
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[Expression of E-cadherin, N-cadherin, β-catenin and their clinical significance in laryngeal carcinoma]. ZHONGHUA ER BI YAN HOU TOU JING WAI KE ZA ZHI = CHINESE JOURNAL OF OTORHINOLARYNGOLOGY HEAD AND NECK SURGERY 2017; 51:440-5. [PMID: 27345880 DOI: 10.3760/cma.j.issn.1673-0860.2016.06.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To investigate the expression of E-cadherin(E-cad), N-cadherin(N-cad), β-catenin(β-cat), which are the markers of Epithelial-mesenchymal transition and analyze their relationships with the clinicopathological features and the prognosis of the laryngeal squamous cell carcinoma. METHODS The expression levels of E-cad, N-cad, β-cat in 76 tumor tissues and their corresponding adjacent normal laryngeal tissues were determined by immunohistochemistry method. Relationships between the proteins' expression and clinicopathological features were analyzed. Survival curves were calculated using the Kaplan-Meier method. Differences in the survival rates were analyzed by the log-rank test among different expression groups. Cox's regression model was used to examine the independent predictor of the prognosis of the laryngeal cancer. RESULTS The expression levels of E-cad, N-cad, β-cat in tumor tissues and adjacent normal tissues were statistically significant(P<0.001). The expression level of E-cad and β-cat in the laryngeal carcinoma was related to lymph node metastasis, clinical pathological stage and differentiation degree (P<0.05), while N-cad expression level was associated with clinical stage and differentiation degree (P<0.05). The expression of E-cad was correlated with the expression of β-cat (P=0.001), and the expression of N-cad was correlated with β-cat (P=0.02), but the expression of E-cad was not correlated with N-cad. There were four subgroups of patterns of E-cad and N-cad expression: E-cad (+ )/N-cad (-), E-cad (+ ) /N-cad (+ ), E-cad (-) /N-cad (-), E-cad (-) /N-cad (+ ). The expression level of each group was related to the clinical pathological stage and differentiation degree (P<0.05). The expression level of E-cad/β-cat was associated with lymph node metastasis, clinical pathological stage and differentiation degree (P<0.01). Log-rank analysis showed that the prognosis of negative and positive groups was statistically different (P<0.05), and the combined analysis showed that the prognosis of E-cad/N-cad or E-cad/β-cat group was significantly different (P<0.01). Cox's regression model analysis showed that the clinical stage and β-cat were independent predictors of the prognosis of laryngeal carcinoma. CONCLUSIONS The low expression of E-cad, high abnormal expression of N-cad and β-cat played an important role in the occurrence and development of laryngeal carcinoma. It can provide a reference for evaluating clinical prognosis. The clinical pathological stage and β-cat can be used as independent predictors for the prognosis of laryngeal carcinoma.
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[A child with palate fistula after coblation adenotonsillectomy]. ZHONGHUA ER BI YAN HOU TOU JING WAI KE ZA ZHI = CHINESE JOURNAL OF OTORHINOLARYNGOLOGY HEAD AND NECK SURGERY 2017; 52:113-114. [PMID: 28219172 DOI: 10.3760/cma.j.issn.1673-0860.2017.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
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Long-term treatment efficacy in primary inflammatory breast cancer by hormonal receptor- and HER2-defined subtypes. Ann Oncol 2013; 25:384-91. [PMID: 24351399 DOI: 10.1093/annonc/mdt525] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Subtypes defined by hormonal receptor (HR) and HER2 status have not been well studied in inflammatory breast cancer (IBC). We characterized clinical parameters and long-term outcomes, and compared pathological complete response (pCR) rates by HR/HER2 subtype in a large IBC patient population. We also compared disease-free survival (DFS) and overall survival (OS) between IBC patients who received targeted therapies (anti-hormonal, anti-HER2) and those who did not. PATIENTS AND METHODS We retrospectively reviewed the records of patients diagnosed with IBC and treated at MD Anderson Cancer Center from January 1989 to January 2011. Of those, 527 patients had received neoadjuvant chemotherapy and had available information on estrogen receptor (ER), progesterone receptor (PR), and HER2 status. HR status was considered positive if either ER or PR status was positive. Using the Kaplan-Meier method, we estimated median DFS and OS durations from the time of definitive surgery. Using the Cox proportional hazards regression model, we determined the effect of prognostic factors on DFS and OS. Results were compared by subtype. RESULTS The overall pCR rate in stage III IBC was 15.2%, with the HR-positive/HER2-negative subtype showing the lowest rate (7.5%) and the HR-negative/HER2-positive subtype, the highest (30.6%). The HR-negative, HER2-negative subtype (triple-negative breast cancer, TNBC) had the worst survival rate. HR-positive disease, irrespective of HER2 status, had poor prognosis that did not differ from that of the HR-negative/HER2-positive subtype with regard to OS or DFS. Achieving pCR, no evidence of vascular invasion, non-TNBC, adjuvant hormonal therapy, and radiotherapy were associated with longer DFS and OS. CONCLUSIONS Hormone receptor and HER2 molecular subtypes had limited predictive and prognostic power in our IBC population. All molecular subtypes of IBC had a poor prognosis. HR-positive status did not necessarily confer a good prognosis. For all IBC subtypes, novel, specific treatment strategies are needed in the neoadjuvant and adjuvant settings.
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Abstract P6-12-02: Survival differences between patients with metastatic inflammatory and non-inflammatory breast cancer. Cancer Res 2013. [DOI: 10.1158/0008-5472.sabcs13-p6-12-02] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Very little is known about the survival of patients with inflammatory breast cancer (IBC) and distant metastasis. Furthermore, the American Joint Committee on Cancer classification of breast cancer does not recognize metastatic IBC as a distinct entity within stage IV. We hypothesized that the survival of patients with IBC and distant metastasis is worse than the survival of patients with stage-matched non-IBC.
Patients and Methods: We retrospectively reviewed 5314 consecutive patients with stage III or IV breast cancer (IBC or non-IBC) who were treated at our institution between 1986 and 2012. A total of 1079 patients presented with IBC (stage III: 861; stage IV: 218) and 4235 non-IBC (stage III: 2781; stage IV: 1454). We compared the time to distant metastasis from initial diagnosis, distant metastasis–free survival (DMFS), and overall survival (OS) in stage-matched patients with IBC or non-IBC.
Results: The median follow-up periods were 3.3 years for patients with stage III disease (range, 0-32.2 years) and 1.8 years for patients with stage IV disease (range, 0-19.9 years). The total number of recorded events (metastasis/death) was 1657 for stage III, while the numbers of deaths for stage III and IV were 1337 and 973, respectively. In patients with stage III, the time to distant metastasis was shorter in IBC than in non-IBC (median 1.3 vs. 1.7 years, P < .001). DMFS and OS were shorter in patients with stage III IBC than in those with stage III non-IBC (2.5 vs. 6.9 years, P < .001; and 4.7 vs. 8.9 years, P < .001; respectively). However, there was no significant difference in OS after development of distant metastasis between stage III IBC and non-IBC (median for both 1.3 years, P = .83). In multivariate analysis, the diagnosis of IBC remained significantly associated with mortality after adjusting for potential confounders. De novo stage IV IBC presented more frequently with multiple sites of metastasis than de novo stage IV non-IBC (P = .02). In patients with de novo stage IV disease, OS was shorter in IBC than in non-IBC (2.3 vs. 3.4 years, P = .004). In the multicovariate Cox model, while ethnicity, tumor grade, hormone receptor status and HER2 status, site of metastasis, number of sites of metastasis, and definitive breast surgery by 1 year were all significant factors in OS for stage IV breast cancer, the diagnosis of IBC conferred a hazard ratio of 1.33 (95% confidence interval: 1.05 - 1.69) in multivariate analysis.
Conclusion: Our findings suggest that IBC patients with metastasis at diagnosis have worse outcomes than stage-matched non-IBC patients. IBC patients presenting with de novo stage IV disease should be considered as a separate subcategory of stage IV in the tumor-node-metastasis classification because their clinical course and prognosis are different from those of patients with stage IV non-IBC.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-12-02.
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Change of selenium in environment and risk of adolescent idiopathic scoliosis: a retrospective cohort study. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2013; 17:2499-2503. [PMID: 24089230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
OBJECTIVES Scoliosis is the disease which has a long history over one century. However, the pathogenesis remains unclear at present. To demonstrate the effect of different selenium content in environment on the morbidity of adolescent idiopathic scoliosis (AIS). METHODS Retrospective cohort study (follow-up from 1997 to 2009): compare the difference morbidity between high selenium group and the normal selenium group of AIS. PATIENTS 9998 cases from three areas in China were participated in this study. There is different selenium content in these three areas. RESULTS High selenium levels were significant associated with the AIS morbidity. While low selenium level had no significant correlation with the AIS morbidity. CONCLUSIONS This study confirmed that high selenium content in the environment was one of risk factors for idiopathic scoliosis. We speculated that the excessive growth of the spine and the spinal cord asynchronous growth effect were key factors that high selenium content in the environment leads to scoliosis.
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Protection Efficacy of Multivalent Egg Yolk Immunoglobulin against Eimeria tenella Infection in Chickens. IRANIAN JOURNAL OF PARASITOLOGY 2013; 8:449-58. [PMID: 24454440 PMCID: PMC3887248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 05/27/2013] [Indexed: 11/03/2022]
Abstract
BACKGROUND To control avian coccidiosis with drug-independent strategy effectively and safely, multivalent hyperimmune egg yolk immunoglobulin (IgY) was prepared and its ability to protect against Eimeria tenella infection was evaluated. METHODS Hens were orally immunized with live oocysts of 5 species of Eimeria for six times, antibody titers in serum and yolk were monitored by indirect enzyme-linked immunosorbent assay. The specific IgY was isolated, purified and lyophilized. IgY powder was orally administrated as dietary supplement in newly hatched chicks at various dosages. Birds were orally challenged with 10000 sporulated oocysts of E. tenella at 10 days of age, weighed and killed at 8 days post challenge, and the protective effect was assessed. RESULTS The averge yeid of IgY was 9.2 mg/ml yolk, the antibody titer of IgY reached to 1:163840 per mg with the purity up to 98%. Chickens fed IgY resulted in reduced mortality, increased body weight gain (BWG), reduced oocyst shedding, reduced caecal lesion score and increased anti-coccidial index. In terms of BWG and caecal lesion, IgY significantly enhanced the resistance of bird at ≥ 0.05% of IgY in the diet when compared with the challenged control group (P<0.05). No significant difference was observed at dosage ≥ 0.5% and 1.0% when BWG and caecal lesion were compared with the sodium salinomycin control group, respectively (P>0.05). CONCLUSION Supplementing newly hatched chicks with Eimeria-specific IgY represents a promising strategy to prevent avian coccidiosis.
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Abstract PD03-08: Statin use and improved outcome in primary inflammatory breast cancer: retrospective cohort study. Cancer Res 2012. [DOI: 10.1158/0008-5472.sabcs12-pd03-08] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background Inflammatory breast cancer (IBC) is the most aggressive type of breast cancer. HMG-CoA reductase inhibitors (statins) are cholesterol reducing agents with pleiotropic effects, including antitumorigenic and anti-inflammatory properties. We hypothesized that statins reduce the metastatic potential in primary IBC.
Methods We retrospectively reviewed 724 patients diagnosed with and treated for primary IBC at The University of Texas MD Anderson Cancer Center between Jan. 12, 1995 and Jan. 27, 2011. Patients with records indicating statin use at the time of IBC diagnosis on the electronic medical record were compared with those without. We further compared outcomes stratified by statin type (hydrophilic [H] versus lipophilic [L]). We used the Kaplan-Meier method to estimate the median disease-free survival (DFS) after surgery, overall survival (OS), and disease specific survival (DSS), followed by Cox proportional hazards regression model to test statistical significance of several potential prognostic factors.
Results For primary IBC patients who had information on their statin use status at IBC diagnosis, the median DFS time were 4.88 years, 2.47 years and 1.76 years (P= 0.04); the median OS time 5.05 years, 3.79 years and 4.32 years (P= 0.35); and the median DSS time 5.10 years, 3.79 years and 4.52 years (P= 0.37), for patients who took “ H”, “L” and no statin, respectively. In multivariable Cox model stratified by radiation therapy, ER/PR status and HER2 status, statin “H” use was associated with significantly improved DFS compared to no statin use (HR=0.49; 95% CI: 0.28–0.84; p<0.01), adjusted for lymphatic/vascular invasion. Although there is a trend that patients who used statin “H” had a longer time to death compared to patients who did not take statin, it did not reach statistical significance for OS (HR=0.80; 95% CI: 0.43–1.49; p=0.49) and DSS (HR=0.85; 95% CI: 0.46–1.57, p=0.59) after adjustment for lymphatic/vascular invasion, nuclear grade and surgery status within one year.
Conclusions Hydrophilic statin use was associated with improved DFS. There was a trend for reduced HR in OS and DSS among primary IBC patient who used hydrophilic statins. A prospective randomized study to evaluate the potential survival benefits of statins in primary IBC population is warranted.
Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD03-08.
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The impact of phosphorylated AMP-activated protein kinase expression on lung cancer survival. Ann Oncol 2012; 23:78-85. [PMID: 21430184 PMCID: PMC3276321 DOI: 10.1093/annonc/mdr036] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Revised: 01/18/2011] [Accepted: 01/21/2011] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The aim of this study is to investigate the prognostic role of phosphorylated AMP-activated protein kinase (pAMPK) in surgically resected non-small-cell lung cancer (NSCLC). METHODS Immunohistochemical staining of pAMPK was carried out on tissue microarrays containing 463 samples obtained from patients with NSCLC and correlated with clinicopathological characteristics and survival. RESULTS pAMPK expression levels were significantly higher in never smokers versus former smokers versus current smokers (P=0.045). A positive pAMPK expression was associated with increased overall survival (OS) and recurrence-free survival (RFS) (P=0.0009 and P=0.0007, respectively). OS and RFS were statistically superior in pAMPK-positive than in pAMPK-negative patients with adenocarcinoma (ADC; median OS: 5.6 and 4.2 years, respectively, P=0.0001; median RFS: 5.0 and 2.4 years, respectively, P=0.001), whereas they were similar in those patients with squamous cell carcinoma. Multivariate analysis confirmed that pAMPK positivity was associated with OS [hazard ratio (HR)=0.574, 95% confidence interval (CI) 0.418-0.789, P=0.0006) and RFS (HR=0.608, 95% CI 0.459-0.807, and P=0.0006), independent of clinical covariates. CONCLUSIONS High pAMPK expression levels are associated with increased survival in patients with NSCLC, especially those with ADC. Our results support further evaluation of AMP-activated protein kinase as a potential prognostic and therapeutic target for lung cancer.
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Isolation, sequence identification and expression profile of three novel genes Rab2A, Rab3A and Rab7A from Black-boned sheep (Ovis aries). Mol Biol (Mosk) 2010; 44:20-27. [PMID: 20198855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Complete coding sequences of three Black-boned sheep (Ovis aries) genes Rab2A, Rab3A and Rab7A were amplified using reverse transcription polymerase chain reaction (RT-PCR) based on the conserved sequence information of cattle or other mammals known to be highly homologous to sheep ESTs. The Black-boned sheep Rab2A gene encodes a protein of 226 amino acids which contains the conserved putative RabL2 domain and is highly homologous to the Rab2A proteins of seven other species--cattle (96%), human (83%), Sumatran orangutan (82%), rat (81%), mouse (80%), African clawed frog (72%) and zebrafish (71%). The Black-boned sheep Rab3A gene encodes a protein of 220 amino acids that contains the conserved putative Rab3 domain and is very similar to the Rab3A proteins of four species--cattle (99%), African clawed frog (99%), Western clawed frog (98%) and zebrafish (95%). And the Black-boned sheep Rab7A gene encodes a protein of 207 amino acids that contains the conserved putative Rab7 domain and has high homology with the Rab7A proteins of six other species--human (99%), dog (99%), Sumatran orangutan (99%), zebrafish (97%), rabbit (97%) and African clawed frog (96%). Analysis of the phylogenetic tree has demonstrated that the Black-boned sheep Rab2A, Rab3A and Rab7A proteins share a common ancestor and the tissue expression analysis has shown that the corresponding genes are expressed in a range of tissues including leg muscle, kidney, skin, longissimus dorsi muscle, spleen, heart and liver. Our experiment is the first to provide the primary foundation for a further insight into these three sheep genes.
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Abstract
Poly (ADP-ribose) synthase or polymerase (PARS and PARP, respectively) is a cytotoxic enzyme which causes cellular damage. Nicotinamide, a compound of vitamin B complex, has been reported to exert an inhibitory effect on PARS or PARP. The present study tests the effects of nicotinamide on acute lung injury and associated alterations following ischaemia/reperfusion (I/R) of the isolated perfused rat's lung. I/R increased the lung weight (LW) to body weight ratio, LW gain, protein and dye tracer leakage, pulmonary arterial pressure and capillary permeability. The insult also increased nitrate/nitrite, methyl guanidine, tumour necrosis factor-alpha and interleukin-1beta in lung perfusate, while it decreased adenosine triphosphate content with an increase in PARP activity in lung tissue. Most of the I/R-induced changes were abrogated by post-treatment (30 min after I/R) with nicotinamide (100 mg.kg(-1) body weight). However, the increase in pulmonary arterial pressure was enhanced by nicotinamide post-treatment. Following I/R, the inducible nitric oxide synthase (iNOS) mRNA expression was enhanced. Nicotinamide reduced the iNOS expression. The results suggest that nicotinamide exerted a protective effect on the acute lung injury caused by ischaemia/reperfusion. The mechanisms may be mediated through the inhibition on the poly (adenosine diphosphate-ribose) polymerase activity, inducible nitric oxide synthase expression and the subsequent suppression of nitric oxide, free radicals and pro-inflammatory cytokines with restoration of adenosine triphosphate.
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Stem cell therapy in stroke: strategies in basic study and clinical application. ACTA NEUROCHIRURGICA. SUPPLEMENT 2006; 99:137-9. [PMID: 17370780 DOI: 10.1007/978-3-211-35205-2_26] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Stem cell therapies are an important strategy for the treatment of stroke. Bone marrow-derived stem cells (BMSCs) may promote structural and functional repair in several organs via stem cell plasticity. The tissue damage could stimulate the stem cells migration, and they track into the site of damage and then undergo differentiation. The plasticity functions of BMSCs in an injuries tissue are dependent on the specific signals present in the local environment of the damaged tissue. Recent studies have also identified the specific molecular signals, such as SDF-1/CXCR4, required for the interaction of BMSCs and damaged host tissues. This review summarizes the current understanding of how BMSCs reach and function in cerebral ischemic tissues.
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A retrospective analysis of the outcome of patients who have received two prior chemotherapy regimens including platinum and docetaxel for recurrent non-small-cell lung cancer. Lung Cancer 2003; 39:55-61. [PMID: 12499095 DOI: 10.1016/s0169-5002(02)00308-2] [Citation(s) in RCA: 166] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
With the availability of chemotherapy agents for first- and second-line treatment of advanced non-small-cell lung cancer (NSCLC), the patient population that requires subsequent chemotherapy is increasing. This retrospective analysis was performed to describe the clinical course after two standard or approved chemotherapy agents in patients with good overall performance status. Data were selected from patients with advanced NSCLC who had received third- or fourth-line chemotherapy after two prior chemotherapy regimens that included platinum and docetaxel given concurrently or sequentially. Prior regiments had failed due to discase progression within 90 days of chemotherapy, or unacceptable toxicity. Examination of over 700 patient records between January 1993 and January 2000 at one US and one European cancer centre revealed 43 patients that fulfilled the inclusion criteria. Response rates decreased with each line of treatment: first line, 20.9%; second line, 16.3%; third line, 2.3%; and fourth line, 0%. The disease control rate (response plus stable disease) also decreased dramatically from first- to fourth-line treatment, although it was higher for second-line treatment (74.4%) than for first-line treatment (62.8%). The median overall survival time from diagnosis was 16.4 months. The median overall survival time from the start of the last treatment (either third or fourth line) was 4 months. Patients with stage III disease at diagnosis had a longer overall survival from diagnosis than patients with stage IV disease (P=0.02). This review highlights the need for novel therapy approaches for patients with recurrent NSCLC who have failed second-line therapy and provides a baseline for the statistical design of such studies.
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Loss of PTEN expression as a prognostic marker for tongue cancer. ARCHIVES OF OTOLARYNGOLOGY--HEAD & NECK SURGERY 2001; 127:1441-5. [PMID: 11735811 DOI: 10.1001/archotol.127.12.1441] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
BACKGROUND Abnormalities of PTEN, a candidate tumor suppressor gene located at 10q23.3, play an important role in the tumorigenesis of multiple tumor types. OBJECTIVES To investigate the expression of PTEN and its clinical implication in squamous cell carcinoma of the tongue. DESIGN Retrospective analysis of PTEN protein expression in archived primary oral tongue tumor samples. SETTING Academic center. PATIENTS AND METHODS PTEN expression was determined by immunohistochemical analysis in tissue samples from 41 patients with stage II, III, and IV squamous cell carcinoma of the tongue. All the patients underwent curative surgical treatment with a median follow-up of 81 months. The Kaplan-Meier method was used for survival analysis. Multivariate analysis was performed according to the Cox proportional hazards model. RESULTS Lack of staining for PTEN was demonstrated in 12 (29%) of the 41 tumors. Patients whose tumors lacked PTEN expression had a significantly shorter overall survival time (P = .03) and event-free survival time (P = .01) than those patients with positive PTEN expression. Multivariate regression analysis demonstrated that PTEN expression is an independent predictor of poor outcome when compared with tumor stage and nodal status. CONCLUSIONS Although genetic alterations of the PTEN gene are rare in head and neck squamous cell carcinoma, loss of PTEN is not an uncommon event in squamous cell carcinoma of the tongue. Lack of PTEN expression may be an independent prognostic indicator for clinical outcome in patients with this tumor type.
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Sodium nitroprusside increases pacemaker rhythm of sinoatrial nodes via nitric oxide-cGMP pathway. CHINESE J PHYSIOL 2000; 43:113-7. [PMID: 11132087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Effects of sodium nitroprusside (SNP), a nitric oxide donor, on the action potential in isolated guinea-pig sinoatrial nodes and ventricular papillary muscles were investigated. In the driven ventricular papillary muscle, SNP (10(-10)-10(-3) M) decreased the twitch tension in a concentration-dependent manner without significantly changing the configuration of action potential and the maximal velocity of depolarizing upstroke. In isolated sinoatrial nodes, SNP (10(-8)-10(-3) M) increased the pacemaker rhythm in a concentration-dependent manner. At 10(-5) M SNP, the pacemaker activity increased from 197.2+/-6.1 to 221.4+/-9.7 bpm. Changes of configuration of the action potential included a decrease of the duration of repolarization, i.e., from peak to the maximal diastolic potential (MDP), from 141.4+/-6.4 to 130.0+/-7.0 ms and an increase of the slope of the diastolic membrane potential from 101.6+/-5.3 to 116.5+/-7.3 mV/s (n=6, p<0.05). However, MDP and threshold potential were not significantly changed. Methylene blue (MB, 10(-5) M), a guanylate cyclase inhibitor, significantly decreased the pacemaker activity of the sinoatrial node by increasing the durations of repolarization and diastolic depolarization. After pretreatment with 10(-5) M MB, the effect of SNP was inhibited. The results indicate that nitric oxide, released from SNP, increases the pacemaker activity by enhancing the rates of repolarization and diastolic depolarization. These effects are possibly due to increases in delayed-rectifier K+ and diastolic slow inward currents, which are involved in a mechanism associated with the NO-cGMP pathway.
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Opposition of rapid baroreceptor resetting by prostanoids in rabbits. CHINESE J PHYSIOL 2000; 43:15-21. [PMID: 10857464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Arterial baroreceptors reset rapidly within minutes during acute hypertension; baroreceptor pressure threshold (Pth) is increased and the pressure-baroreceptor activity relation is shifted to the right. The purpose of the present study was to determine if prostacyclin (PGI2) or other prostanoids, released during acute hypertension modulate the magnitude of baroreceptor resetting. Baroreceptor activity was recorded from the vascularly-isolated carotid sinus during distension of the sinus with slow pressure ramp in rabbits anesthetized with chloralose. Pressure-activity curves were generated after holding carotid sinus pressure for 10-15 min from 30 to 100 mmHg. In control, the elevation of holding pressure increased Pth from 44+/- to 65+/-5 mmHg (p < 0.05, n = 12). In the presence of PGI2 (20 microM), Pth averaged 43+/-4 and 45+/-3 mmHg (n = 12) after holding pressure at 30 and 100 mmHg, respectively. In the control group before exposing the carotid sinus to indomethacin, an elevation of holding pressure increased Pth from 49+/-2 to 71+/-3 mmHg (p < 0.05, n = 12). After inhibition of the endogenous formation of prostanoids with indomethacin (20 microM), Pth increased by a significantly greater extent from 61+/-2 to 90+/-3 mmHg (p < 0.05, n = 12) with the increase in holding pressure. The slope of the pressure-activity curve (baroreceptor gain) was not influenced by the change in holding pressure. It was increased significantly by PGI2, while decreased by indomethacin. Neither the change in holding pressure nor PGI2 affected the circumferential wall strain of carotid sinus over a wide range of pressure alteration. The results suggest that PGI2 or other prostanoids released during acute hypertension sensitizes baroreceptors and provides a negative feedback mechanism that opposes and limits the magnitude of rapid baroreceptor resetting.
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Two-element dielectric antenna serially excited by optical wavelength multiplexing. OPTICS LETTERS 1999; 24:235-237. [PMID: 18071465 DOI: 10.1364/ol.24.000235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A single pulsed laser beam containing multiple wavelengths (wavelength multiplexing) is employed to activate two semiconductor antennas in series. The dielectric nature of the semiconductors permits serial cascading of the antenna elements. Recently observed nonlinear characteristics of the radiated field as a function of the free carrier accelerating (bias) voltage are used to minimize the small interactions between elements. We demonstrate that the temporal electromagnetic radiation distribution of two serial antennas is sensitive to the three-dimensional pattern of the optical excitation source. One can, in turn, vary this distribution continuously by optical means to reconfigure the array.
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Activation of gonadotropin-releasing hormone receptors induces a long-term enhancement of excitatory postsynaptic currents mediated by ionotropic glutamate receptors in the rat hippocampus. Neurosci Lett 1999; 260:33-6. [PMID: 10027693 DOI: 10.1016/s0304-3940(98)00939-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Whole-cell patch-clamp recordings were made from CA1 pyramidal neurons of the rat hippocampus to study the modulation of gonadotropin-releasing hormone (GnRH) on synaptic transmission mediated by ionotropic glutamate receptors. Leuprolide (10(-9)-10(-7) M), a specific GnRH analog, concentration-dependently elicited a long-lasting potentiation of excitatory postsynaptic currents (EPSCs) mediated by ionotropic glutamate receptors. GnRH receptor-induced synaptic potentiation was blocked by 1 microM [Acetyl-3,4-dehydro-Pro1,D-p-F-Phe2,D-Trp3,6]-LHRH, a specific GnRH receptor antagonist. Furthermore, GnRH receptor-induced synaptic potentiation was associated with the stimulation of protein kinase C (PKC), being considerably attenuated by a potent PKC inhibitor (30 microM H-7). The results suggest a long-term enhanced modulation of GnRH on synaptic transmission mediated by ionotropic glutamate receptors, possibly via the actions of PKC in the hippocampus that is an important integrative system in the regulation of reproductive processes.
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Free radicals are involved in methylmethacrylate-induced neurotoxicity in human primary neocortical cell cultures. CHINESE J PHYSIOL 1998; 41:203-9. [PMID: 10099867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
Methylmethacrylate monomer (MMA), a highly volatile material, has been extensively used for the construction of complete or partial dental prostheses. While previous studies have indicated a variety of complications and untoward side-effects associated with its use, the possible neurotoxicity induced by this monomer has not been addressed. In this study, we have investigated the MMA-produced neuronal injury in human neuron-enriched primary culture. Embryonic brain tissue (8-10 weeks postconception) was used for the primary neuron-enriched culture. Phase-contrast microscopy was used to evaluate morphological changes of cultured neurons. Extracellular concentrations of lactate dehydrogenase (LDH) and nitrite was measured from the culture medium to assess the magnitude of neuronal damage and nitric oxide formation, respectively. Neocortical neurons exposed to the monomer (1/200, Vmonomer/Vglycerol) for two days resulted in a significant increase in the LDH level but monomer (1/20000, 1/2000, or 1/200; Vmonomer/Vglycerol) failed to increase the nitrite level. Morphologically, the neurons subjected to monomer treatment exhibited irregular shrunken cell bodies with dystrophic and/or fragmented neurities, or even cell lysis. Moreover, superoxide dismutase plus catalase or vitamin C pretreatment protected against monomer-induced neurotoxicity. Our results suggest that this neurotoxicity can not likely be attributed to the cytotoxic effects of nitric oxide but may be mediated through the toxicity of superoxide and other free radicals. This is the first time, to our knowledge, that neurotoxicity induced by MMA has been demonstrated in human cortical neurons.
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The involvement of nitric oxide in synergistic neuronal damage induced by beta-amyloid peptide and glutamate in primary rat cortical neurons. CHINESE J PHYSIOL 1998; 41:175-9. [PMID: 9915130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
Abnormal extracellular accumulation of beta-amyloid (Abeta), the major component of senile plaques in the Alzheimer's brain and the excitatory amino acid glutamate are both considered to be associated with neurodegeneration. We studied whether nitric oxide (NO) was involved in neuronal damage induced by Abeta and glutamate in primary rat cortical neurons. Our results demonstrated that (1) Both neuronal damage and NO production were synergistically induced by Abeta-(25-35) and glutamate; (2) This synergistic neuronal damage induced by Abeta-(25-35) and glutamate was attenuated by selective inhibitors of NO synthase. We propose that cytotoxic characteristics of NO, at least in part, are involved in the synergistic neuronal damage induced by Abeta and glutamate, presumably seen in Alzheimer's brains.
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Estimation and correction of ultrasonic wavefront distortion using pulse-echo data received in a two-dimensional aperture. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 1998; 45:473-90. [PMID: 18244198 DOI: 10.1109/58.660157] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Pulse-echo measurements from random scattering and from a point target have been used to quantify transmitter beam size effects and isoplanatic patch size as well as to evaluate the performance of different aberration compensation techniques. Measurements were made using a single-element transmitter with a diameter of 1/2 in., 1 in., or 2 in., each focused at 3 in. A tissue-mimicking scattering phantom or a point target was used to produce echoes that were received in a two-dimensional aperture synthesized by scanning a linear array. A specimen of abdominal wall was placed in the reception path to produce aberration. B-scan images were formed with no compensation, with time-shift compensation in the receiving aperture, and with backpropagation followed by time-shift compensation. The isoplanatic patch size was estimated by compensating the focus of a test point target with the parameters estimated for an original point target position, and observing the deterioration of compensation effects with increasing distance between the test and the original point targets. The results of the measurements using different transmitter diameters quantify the improvement of time-delay estimation with the increase in wavefront coherence that accompanies decreased transmitter beam size. For seven specimens, the average isoplanatic patch size determined from a 10% increase in the -10 dB effective diameter was 16.7 mm in the azimuthal direction and 39.0 mm in the range direction. These sizes increased after backpropagation to 19.0 mm and 41.4 mm, respectively. For the 1/2 in., 1 in., and 2 in. diameter transmitters, the average contrast ratio improvement was 2.0 dB, 2.1 dB, and 2.8 dB, respectively, with time-shift compensation, and 2.3 dB, 2.7 dB, and 3.5 dB, respectively, with backpropagation of 20 mm followed by time-delay estimation and compensation. The investigation indicates that a tightly focused transmitter beam is necessary to create a scattered wavefront satisfactory for time-shift estimation, the isoplanatic patch is about twice as long in the range direction as in the azimuthal direction, and backpropagation followed by time-shift compensation provides better compensation of distortion than time-shift compensation alone.
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Feasibility of angle independent Doppler color imaging for in vivo application: preliminary study on carotid arteries. ULTRASOUND IN MEDICINE & BIOLOGY 1997; 23:59-67. [PMID: 9080618 DOI: 10.1016/s0301-5629(96)00182-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
An experimental system has been used to acquire Doppler color images using a linear transducer from an ultrasound scanner to reconstruct angle independent Doppler color (AIDC) images in normal carotid arteries in 21 volunteers. Images were first taken from relatively straight segments in the common carotid artery, and comparisons were made in a small area at the center stream. At peak systole, the correlation coefficient of the velocity amplitudes between AIDC imaging (AIDCI) and duplex scanning was 0.94; the correlation coefficient between the flow angles measured from AIDCI and the angles of the vessel wall was 0.99. Periodic variations of the flow angle over the cardiac cycle were always observed by AIDCI, whereas the changes in the geometric angle of the vessel itself were insignificant. This observation suggests that the AIDCI technique is sensitive to alterations of flow direction. On the other hand, the deviation of the flow angle from a fixed correction angle in duplex scanning may cause a certain degree of error in velocity determination. AIDC images were also obtained at the carotid bifurcation. The results show that the AIDCI technique is able to depict major flow features, such as velocity skewing, flow separation, flow reversal and vortical flow, in a complex flow field.
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Multimodality multidimensional image analysis of cortical and subcortical plasticity in the rat brain. Ann Biomed Eng 1996; 24:430-9. [PMID: 8734064 DOI: 10.1007/bf02660892] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
In this work, we developed and implemented a multimodality multidimensional imaging system which is capable of generating and displaying anatomical and functional images of selected structures and processes within a vertebrate's central nervous system (CNS). The functional images are generated from [14C]-2-deoxy-D-glucose (2DG) autoradiography whereas the anatomic images are derived from cytochrome oxidase (CO) histochemistry. This multi-modality imaging system has been used to study mechanisms underlying information processing in the rat brain. We have applied this technique to visualize and measure the plasticity (deformation) observed in the rat's whisker system due to neonatal lesioning of selected peripheral sensory organs. Application of this imaging system revealed detailed information about the shape, size, and directionality of selected cortical and subcortical structures. Previous 2-D imaging techniques were unable to deliver such holistic information. Another important issue addressed in this work is related to image registration problems. We developed an image registration technique which employs extrinsic fiduciary marks for alignment and is capable of registering images with subpixel accuracy. It uses the information from all available fiduciary marks to promote alignment of the sections and to avoid propagation of errors across a serial data set.
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Computer implementation in the reconstruction of 2-D flow velocity fields in ultrasound Doppler color imaging. Comput Biol Med 1995; 25:495-503. [PMID: 8665795 DOI: 10.1016/0010-4825(95)00039-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Doppler color imaging can easily render flow information within the vessels and simultaneously provide anatomic information for diagnostic purposes. However, the angle dependence problem of the Doppler velocity measurement is a significant barrier for continuing progress toward quantitative clinical applications of this technology. This paper presents a method and the computer implementation for reconstruction of the 2-D flow velocity field (angle independent) in ultrasound Doppler color imaging. Formulae for deriving angle independent velocity amplitude and angle direction from the color images acquired with a linear array transducer are given. The hardware configuration of the data acquiring and processing system is described. Major considerations in the development of algorithms, especially the strategies for reducing the computation time are presented.
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Off-axis holographic technique for particle image velocimetry using a Fourier-transform lens. OPTICS LETTERS 1995; 20:327-329. [PMID: 19859176 DOI: 10.1364/ol.20.000327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We propose and demonstrate a simple off-axis scheme for particle field holography that utilizes the particle forward scattering by means of a Fourier transform lens for both recording and reconstruction. This technique has the advantages of both the low speckle noise offered by off-axis holography and the minimal laser power requirement characteristic of in-line illumination.
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[Percutaneous intra-aortic balloon pumping in cardiogenic shock]. ZHONGHUA YI XUE ZA ZHI 1994; 74:290-2, 326. [PMID: 7953920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Eleven patients with cardiogenic shock underwent percutaneous intra-aortic balloon pumping (PIABP). Six (55%) survived and 5 (45%) died. Seven patients were referred to the hospital after acute myocardial infarction and 4 of them survived after the therapy in conjunction with thrombolysis or percutaneous transluminal coronary. In another four patients receiving postcardiotomy, half survived without complication. We believe that PIABP can make early revascularization safe by combating reperfusion injury.
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Stability analysis for grating-tuned strong-external-feedback semiconductor lasers. APPLIED OPTICS 1992; 31:4161-4164. [PMID: 20725396 DOI: 10.1364/ao.31.004161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We give a simple stability analysis within the scope of steady-state solution for the grating-tuned strong-external-feedback semiconductor lasers. In our model, a fluctuation in the refractive index of an active medium through the coupling of carrier density will cause another fluctuation in the refractive index. If the latter is always smaller than the former, the fluctuation will be damped, and therefore the corresponding operating point of the laser is stable. Our analysis indicates that there are various stable and unstable operating-frequency ranges for various reflectivities of the internal facet of the laser diode. In addition, it agrees well with the experimental results and explains the bistability of threshold gain versus operating frequency.
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Determination of carbofuran and its metabolites in rice paddy water by using solid phase extraction and liquid chromatography. JOURNAL - ASSOCIATION OF OFFICIAL ANALYTICAL CHEMISTS 1989; 72:845-7. [PMID: 2808248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A procedure for the determination of carbofuran and its metabolites (carbamate and phenolic) in rice paddy water is described. Water samples are concentrated on a C-18 solid phase extraction (SPE) column and eluted with methanol-water. The eluate is analyzed by reverse-phase liquid chromatography (LC) and measured by a wavelength programmable ultraviolet (UV) detector. The limit of detection for the method is 0.4 micrograms/L. Recovery studies were carried out at levels ranging from 1 to 15 micrograms/L in both rice paddy water and distilled water; recoveries ranged from 85.9 to 112.9%.
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Evidence that alterations in gamma-aminobutyric acid and acetylcholine in rat striata and cerebella are not related to soman-induced convulsions. J Neurochem 1988; 51:181-7. [PMID: 3379402 DOI: 10.1111/j.1471-4159.1988.tb04853.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Many reports have suggested that gamma-aminobutyric acid (GABA) may play a role in organophosphate-induced convulsions. The balance between GABA and acetylcholine (ACh) in the brain also has been suggested by some investigators to be related to brain excitability. We examined these questions by studying the levels of GABA and ACh and the ratios of GABA to ACh in rat striata and cerebella (two major motor control areas in the CNS) after the administration of soman, an organophosphate acetylcholinesterase inhibitor also known as nerve gas. Male Sprague-Dawley rats weighing 250-300 g were injected subcutaneously with three different doses of soman: a subconvulsive dose of 40 micrograms/kg (approximately 30% of the ED50 for convulsions in rats), a convulsive dose of 120 micrograms/kg (approximately one ED50 for convulsions), and a higher convulsive dose of 150 micrograms/kg (approximately 120% of the ED50 for convulsions). The incidence and severity of convulsions were monitored in individual rats until they were sacrificed by focused microwave irradiation of the head at the following time points after soman administration: 4 min, a time prior to the onset of convulsions; 10 min, the time of onset of convulsions; 1 h, the time of peak convulsive activity; and 6 h, a time at which rats were recovering from convulsions. Results showed that in rat striata and cerebella, neither changes in levels of GABA and ACh nor changes in ratios of GABA to ACh were related to soman-induced convulsions, i.e., none of the changes in either levels or ratios of these two neurotransmitters were related to the initiation of, maintenance of, or recovery from soman-induced convulsions.
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Abstract
Age-related differences in opiate receptors were determined using young (1 month old), mature (3 and 8 months old) and aged (20 months old) mice. 3H-Dihydromorphine binding to mu-receptors in brain synaptic membranes consisted of two components: one with high affinity and one with low affinity. High affinity mu binding sites in membranes from young and aged mice had significantly less receptor densities and higher affinities than the mature mice. In the membranes from aged mouse brain, the affinity of low affinity binding sites for 3H-dihydromorphine was also significantly increased when compared to those in membranes from the 8-month-old group. Membranes from the young and aged groups revealed significantly higher affinity for binding of the kappa ligand, 3H-(-)ethylketocylazocine, than mature mice, which was not accompanied by any change in the density of the receptors. There was no change in either the number or affinity of the binding sites for 3H-(D-Ser2-Leu5)-enkephalinyl-Thr, the delta receptor ligand, among young mature and aged groups.
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Acute effects of Soman, Sarin, and Tabun on cyclic nucleotide metabolism in rat striatum. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 1986; 19:23-32. [PMID: 2875191 DOI: 10.1080/15287398609530903] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Rats were injected sc with 120 micrograms/kg Soman, 120 micrograms/kg Sarin or 240 micrograms/kg Tabun. At 15 min, 2 h, or 6 h after administration, animals were decapitated along with saline-treated controls, and striatal activities of nucleotide cyclases and phosphodiesterases and striatal cyclic nucleotide levels were determined. All three agents had two similar effects on rat striatal cyclic nucleotide systems: they all increased cyclic GMP levels 15 min after their administration, and they all decreased guanylate cyclase activity 2 h after administration. There were also some different effects elicited by these three organophosphorus compounds. Different effects of Soman and Sarin seem to be mainly due to their different potencies, which in turn influence the time course of their actions. Tabun is quite different from Soman and Sarin in several respects: it rarely causes convulsions at sub-lethal doses, it has no effects on striatal cyclic AMP levels, and it affects enzyme activities 6 h after its administration. These differences may be due to the presence of cyanide instead of fluoride in its structure: i.e., this may be responsible for the different effects of Tabun on striatal cyclic nucleotide systems, and perhaps other biochemical effects. These results also indicate that other neurotransmitter systems, in addition to the cholinergic system, may be involved in organophosphate-induced toxicity.
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Relationship between the neurotoxicities of Soman, Sarin and Tabun, and acetylcholinesterase inhibition. Toxicol Lett 1986; 30:121-9. [PMID: 3705100 DOI: 10.1016/0378-4274(86)90094-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Acetylcholinesterase (AChE)-induced chewing movements, tremors, convulsions and hind limb abduction at doses of 50-85% LD50 in rats were monitored in order to determine whether the severity of these different signs would correlate with brain AChE levels and the time course of such a relationship. 30 min after subcutaneous (s.c.) injection of Soman, the intensities of toxic signs were significantly correlated with the degree of striatal AChE inhibition. In the case of Sarin, the corresponding r-values were not significant except for tremors. For Tabun-induced chewing, tremor and hind-limb abduction, the r-values were significant. The neurotoxicity was most intense between 15 min to 2 h after treatment, but at 2 or 6 h, the r-values were well below 0.5. The inhibition of brain AChE was maximal by 30 min and was still high at 24 h.
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