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Cheung CW, Qiu Q, Ying ACL, Choi SW, Law WL, Irwin MG. The effects of intra-operative dexmedetomidine on postoperative pain, side-effects and recovery in colorectal surgery. Anaesthesia 2014; 69:1214-21. [PMID: 24915800 DOI: 10.1111/anae.12759] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2014] [Indexed: 12/15/2022]
Abstract
In this double-blind, randomised study, 100 patients undergoing open or conventional laparoscopic colorectal surgery received an intra-operative loading dose of dexmedetomidine 1 μg.kg(-1) followed by an infusion of 0.5 μg.kg(-1) .h(-1) , or a bolus and infusion of saline 0.9% of equivalent volume. Forty-six patients in the dexmedetomidine group and 50 in the saline group completed the study. The area under the curve of numerical rating scores for pain at rest for 1-48 h postoperatively was significantly lower in the patients receiving dexmedetomidine (p = 0.041). There was no difference in morphine consumption, duration of recovery ward or hospital stay. From the data obtained in this study, we calculated a number needed to treat for effective pain relief of 4. Intra-operative dexmedetomidine in colorectal surgery resulted in a reduction in resting pain scores, but there was no morphine-sparing effect or improvement in patients' recovery outcome measures.
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Lian F, Wang Y, Xu H, Chen D, Zhan Z, Liang L, Qiu Q, Ye Y, Yang X. AB0634 Chinese experience with tripterygium wilfordii multiglycoside as long-term maintenance therapy in lupus nephritis. Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2012-eular.634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Zhuang M, Zhu D, Huang L, Peng X, Qiu Q, Wu R, Lin Z, Chen Z. EP-1609: Volumetric modulated arcs with flattening filter-free beams for recurrent nasopharyngeal carcinoma. Radiother Oncol 2014. [DOI: 10.1016/s0167-8140(15)31727-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Zhan Z, Chen D, Lian F, Qiu Q, Liang L, Yang X. SAT0202 Identification of thiopurine methyltransferase (TPMT) activity can predict azathioprine-related hematotoxicity in the maintenance therapy of systemic lupus erythematosus patients. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2012-eular.3149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Ye Y, Yuan S, Chen D, Zhan Z, Lian F, Qiu Q, Li H, Liang L, Xu H, Yang X. FRI0328 Protective and risk factors related to recurrence and prognosis in lupus enteritis. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2013-eular.1455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Lian F, Wang Y, Xu H, Chen D, Zhan Z, Liang L, Qiu Q, Ye Y, Yang X. THU0157 Tripterygium WILFORDII multiglycoside combined regimen as long-term maintenance therapy in chinese rheumatoid arthritis patients. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2012-eular.2122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Qiu Q, Hu B, Chen ZC, He XS. Sexual dimorphism of STGC3 tumor suppressor function in nasopharyngeal carcinoma CNE2 cells. GENETICS AND MOLECULAR RESEARCH 2012; 11:4585-97. [PMID: 23096911 DOI: 10.4238/2012.october.9.9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
STGC3 is a potential tumor suppressor in nasopharyngeal carcinoma. We previously found that CNE2 cells that re-expressed STGC3 formed smaller tumors in female mice than in male mice. Here, we investigated the sexual dimorphism of STGC3 as a tumor-suppressor in female and male nude mice injected subcutaneously with pcDNA3.1(+)-STGC3/CNE2 cells. ER-α was positively expressed in vitro in the CNE2 cells. The pcDNA3.1(+)-STGC3/CNE2 cell growth rate decreased after treatment with β-estradiol in vitro. There were significant differences in tumor size or mass between pcDNA3.1(+)-STGC3/CNE2 and control cases (P < 0.05), but there were significant differences in tumor size between female and male nude mice in the STGC3 transfection groups, and the pcDNA3.1(+)-STGC3/CNE2 tumor growth rate in the female nude mice was the lowest in all cases (P < 0.05). There were no significant differences between female and male nude mice in control groups. Furthermore, a greater number of cells were blocked in the G(0)/G(1) phase in pcDNA3.1(+)-STGC3/ CNE2 tumor xenografts in the female mice. Protemic analysis found 9 differentially expressed proteins in the pcDNA3.1-STGC3/CNE2 xenograft tissues in females and males. A heat shock 70 protein 8 isoform 2 variant was identified as a down-regulated protein associated with cell cycle control and its downstream factor cyclin D1 was also decreased in STGC3-repressed xenografts in female mice. The data above suggest that STGC3 and its associated proteins play an important role in nasopharyngeal carcinoma gender differences.
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Carnali JO, Madison SA, Shah P, Qiu Q. Structure/Property Relationship for Ethylenediamine Derivatives as Aids in Sunless Tanning. Ind Eng Chem Res 2012. [DOI: 10.1021/ie301929w] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Mishra P, Qiu Q, Gruslin A, Hidaka Y, Mbikay M, Basak A. In Vitro Regulatory Effect of Epididymal Serpin CRES on Protease Activity of Proprotein Convertase PC4/PCSK4. Curr Mol Med 2012; 12:1050-67. [DOI: 10.2174/156652412802480961] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Revised: 04/16/2012] [Accepted: 04/24/2012] [Indexed: 11/22/2022]
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Ferraro ZM, Qiu Q, Gruslin A, Adamo KB. Characterization of the insulin-like growth factor axis in term pregnancies complicated by maternal obesity. Hum Reprod 2012; 27:2467-75. [PMID: 22674202 DOI: 10.1093/humrep/des189] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
STUDY QUESTION Does maternal obesity affect insulin-like growth factor (IGF) axis protein expression patterns in maternal and cord blood? SUMMARY ANSWER Maternal obesity attenuates cord blood expression of IGF-binding protein (IGFBP)-4. WHAT IS KNOWN AND WHAT THIS PAPER ADDS The IGF axis plays a critical role in fetal growth and development. Maternal obesity compromises IGF axis protein expression in fetal circulation, which is consistent with the findings of epidemiological studies suggesting that maternal obesity has an independent effect on fetal growth signals during in utero development. STUDY DESIGN This cross-sectional case-control study involved 12 lean [body mass index (BMI) 18.5-24.9 kg/m2] and 12 obese (BMI≥30 kg/m2) women and their neonates at term. At the completion of the study, IGF axis protein expression and hormone concentrations in both maternal and cord blood were examined. PARTICIPANTS AND SETTING We obtained fasting serum samples from cases and controls matched for age, gestation, mode of delivery, parity and glucose tolerance prior to and immediately following elective caesarean section. The corresponding umbilical cord blood was also collected at birth. MAIN RESULTS AND THE ROLE OF CHANCE Between-group comparisons revealed elevated maternal insulin (P=0.03) and leptin (P<0.01) concentrations in obese gravidas. After adjustment, the maternal homeostasis model of assessment-insulin resistance (HOMA-IR) score was positively correlated with both maternal BMI and leptin levels (P<0.01). Umbilical cord blood levels of IGFBP-3 showed an inverse trend to maternal HOMA-IR (P=0.03) but were directly related to the fetal-placental weight ratio (P<0.01). In cord serum from obese mothers, IGFBP-4 expression was attenuated compared with the controls (P<0.05). LIMITATIONS The limitations of our study include the cross-sectional design and relatively small sample size. WIDER IMPLICATIONS Our results provide preliminary evidence for the applicability of our findings to other ethnic groups when pregnancy is complicated by obesity. STUDY FUNDING/COMPETING INTERESTS This work was supported by the University of Ottawa, Faculty of Health Sciences/Children's Hospital of Eastern Ontario Research Partnership Grant awarded to K.B.A. and Z.M.F. The authors have no conflicts of interest to declare.
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Saleh S, Bagce H, Qiu Q, Fluet G, Merians A, Adamovich S, Tunik E. Mechanisms of neural reorganization in chronic stroke subjects after virtual reality training. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2012; 2011:8118-21. [PMID: 22256226 DOI: 10.1109/iembs.2011.6092002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This study investigates patterns of brain reorganization in chronic stroke subjects after two weeks of robot-assisted arm and hand training in virtual reality (VR). Four subjects were studied with event-related fMRI while doing simple paretic hand finger movements before (double baseline) and after training. Bilateral hand movements were recorded and used to provide real-time feedback to subjects during scanning to eliminate performance confounds on fMRI results. The kinematic parameters of each movement were also used in the general linear model with the BOLD signal to investigate training-induced changes in neuromotor coupling. Univariate analysis showed an increase in BOLD signal in the ipsilesional hemisphere in two subjects and a decrease in activity in the other two subjects. Seed voxel based functional connectivity analysis revealed an increase in connectivity between ipsilesional motor cortex and bilateral sensorimotor cortex during finger movements in all four subjects. Hemispheric laterality index values showed a tendency to decrease reflecting a reduction in the over-dominance of the contralesional hemisphere. The study is novel in terms of 1) tracking finger movement during a motor task in the scanner, 2) monitoring motor performance during the experiment and 3) giving online visual feedback of subjects' movement. This pilot study introduces a novel approach to study neural plasticity by combining measures of regional intensity, interregional interactions (using functional connectivity analysis and hemispheric laterality index), and modulation in the strength of neuromotor coupling.
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Qiu Q, Lu H, Lu C, Chen S, Han H. Variations in TGF-beta, IL-10, and IL-17 after specific immunotherapy and correlations with symptoms in patients with allergic rhinitis. J Investig Allergol Clin Immunol 2012; 22:311-312. [PMID: 22812212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023] Open
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Kaplan R, Qiu Q, Monni S, D'Alfonso T, Shin SJ. P3-07-47: Validated Nomogram To Predict Sentinel Lymph Node Positivity in Breast Cancer Patients. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-p3-07-47] [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: Sentinel lymph node(SLN) biopsy is commonly used to assess axillary lymph node status in breast cancer patients. Intraoperative (frozen section) evaluation of SLN may lead to immediate axillary dissection if the lymph node is found to be positive. In light of the recent outcomes of the Z00011 trial, the use of intraoperative evaluation for SLN should diminish since only select patients appear to benefit from axillary dissection. We have previously reported that tumor size and lymphovascular invasion (LVI) strongly predict SLN positivity in a cohort of 350 breast cancer patients [Modern Pathology (2011) 24, 30A]. From this test cohort, we developed a nomogram which could help identify patients more likely to have sentinel lymph node positivity. The aim of this study was to validate the efficacy of this nomogram by applying a new, non-overlapping cohort of breast cancer patients who had undergone sentinel lymph node sampling. Materials and Methods: 93 breast cancer patients aged 29–82 (mean:59) who underwent excision (54, 58%) or mastectomy (39, 42%) with a SLN biopsy were studied. Patients who had undergone neoadjuvant chemotherapy were excluded. Clinicopathologic parameters such as number of sentinel lymph nodes removed and/or positive, number of non-sentinel lymph nodes removed and/or positive, tumor size, histologic type/grade, presence of lymphovascular invasion, biomarker expression (ER,PR, HER-2/neu) and multifocality were recorded. Statistical analysis was performed to identify which variables correlated with SLN positivity in this validation cohort. In addition, the probability of SLN positivity for each case was determined by using the nomogram and this value was then compared to the patient's true SLN status. Results: When analyzed separately, tumor size (p=0.03) and LVI (p=0.01) were variables that were significantly associated with SLN positivity in both the test and validation cohorts. Employment of the nomogram demonstrated that 60% of patients who were predicted to have a positive SLN with at least 0.8 probability were truly positive by histologic and immunohistochemical examination. Moreover, 89% of patients who were predicted to have a negative SLN with at least 0.8 probability were truly negative by histologic and immunohistochemical examination. Conclusions: We conclude that the utility of this nomogram prior to surgery can help predict SLN positivity. This can serve as a complimentary adjunctive tool to better select patients who will likely need intraoperative evaluation of their sentinel lymph node due to their higher risk of sentinel node positivity and thus, benefit from the option of immediate axillary dissection at that time.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-07-47.
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Haider M, Qiu Q, Bani-Yaghoub M, Tsang BK, Gruslin A. Characterization and role of NUMB in the human extravillous trophopblast. Placenta 2011; 32:441-9. [PMID: 21486681 DOI: 10.1016/j.placenta.2011.03.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Revised: 03/15/2011] [Accepted: 03/17/2011] [Indexed: 01/27/2023]
Abstract
NUMB is a multifunctional protein involved in asymmetric cell differentiation, proliferation and maintenance. Four mammalian NUMB isoforms have been identified, which utilize the phosphotyrosine binding (PTB) domain and the proline rich region (PRR) domain to regulate cell growth and differentiation in the developing nervous system. The observation that a decrease in spongiotrophoblast number and thickness of placentae of null (Numb(-/-)) mouse embryos, which died at E10.5, suggests NUMB may play a role in placental development. In this study, we demonstrated for the first time, that NUMB isoforms 1, 2, 3, and 4 are present in the human placenta and the human extravillous trophoblast (EVT) cell line HTR8/SVneo. We report three novel isoforms, NUMB 7, 8, and 9, identified by cloning of RT-PCR products and sequencing. Corresponding sequences of novel isoforms were submitted to genebank (accession numbers for each new isoform: NUMB 7- EU265736, NUMB 8- EU265737 and NUMB 9-EU265738). Western blot analysis confirmed the presence of all NUMB isofoms in human placental samples in all trimesters and in EVT cells. NUMB immunosignals were extensively localized in human extravillous trophoblasts and decidual cells at the maternal-fetal interface. NUMB 8 appeared to be the predominant isoform in placental villi. Furthermore, cell migration studies revealed NUMB isoform 1 to be involved in EVT cell migration and NUMB isoforms 2 and 4 to induce EVT apoptosis.
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Wang H, Qiu Q, Tan LL, Liu T, Deng XQ, Chen YM, Chen W, Yu XQ, Hu BJ, Chen WQ. Prevalence and determinants of diabetes and impaired fasting glucose among urban community-dwelling adults in Guangzhou, China. DIABETES & METABOLISM 2009; 35:378-84. [DOI: 10.1016/j.diabet.2009.03.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Revised: 03/03/2009] [Accepted: 03/09/2009] [Indexed: 01/15/2023]
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Merians AS, Tunik E, Fluet GG, Qiu Q, Adamovich SV. Innovative approaches to the rehabilitation of upper extremity hemiparesis using virtual environments. Eur J Phys Rehabil Med 2009; 45:123-133. [PMID: 19158659 PMCID: PMC5648052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
AIM Upper-extremity interventions for hemiparesis are a challenging aspect of stroke rehabilitation. Purpose of this paper is to report the feasibility of using virtual environments (VEs) in combination with robotics to assist recovery of hand-arm function and to present preliminary data demonstrating the potential of using sensory manipulations in VE to drive activation in targeted neural regions. METHODS We trained 8 subjects for 8 three hour sessions using a library of complex VE's integrated with robots, comparing training arm and hand separately to training arm and hand together. Instrumented gloves and hand exoskeleton were used for hand tracking and haptic effects. Haptic Master robotic arm was used for arm tracking and generating three-dimensional haptic VEs. To investigate the use of manipulations in VE to drive neural activations, we created a "virtual mirror" that subjects used while performing a unimanual task. Cortical activation was measured with functional MRI (fMRI) and transcranial magnetic stimulation. RESULTS Both groups showed improvement in kinematics and measures of real-world function. The group trained using their arm and hand together showed greater improvement. In a stroke subject, fMRI data suggested virtual mirror feedback could activate the sensorimotor cortex contralateral to the reflected hand (ipsilateral to the moving hand) thus recruiting the lesioned hemisphere. CONCLUSION Gaming simulations interfaced with robotic devices provide a training medium that can modify movement patterns. In addition to showing that our VE therapies can optimize behavioral performance, we show preliminary evidence to support the potential of using specific sensory manipulations to selectively recruit targeted neural circuits.
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Seth S, Maier M, Qiu Q, Ravens I, Kremmer E, Förster R, Bernhardt G. The murine pan T cell marker CD96 is an adhesion receptor for CD155 and nectin-1. Biochem Biophys Res Commun 2007; 364:959-65. [DOI: 10.1016/j.bbrc.2007.10.102] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2007] [Accepted: 10/16/2007] [Indexed: 10/22/2022]
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Qiu Q, Pethica BA, Somasundaran P. Reversible flocculation of silica across the phase boundary of poly(vinyl caprolactam) in aqueous solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:12096-9. [PMID: 16342979 DOI: 10.1021/la0517235] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The colloid stability of silica dispersions in water in the presence of poly(vinyl caprolactam) (PVCAP) has been studied below and above the lower consolute temperature (LCT) of its solutions. The dispersion sediments slowly without PVCAP in the temperature range studied (26-40 degrees C) or with PVCAP below the LCT ( approximately 30 degrees C). In contrast, with PVCAP above the LCT, rapid flocculation occurs at acid pH, with re-dispersal on cooling. Reversible flocculation is also obtained above the LCT by cycling the pH from alkaline to acid and back. The flocculation observed above the LCT may also be regarded as heterocoagulation between the silica particles and the aggregates of the polymer.
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Qiu Q, Yang M, Tsang BK, Gruslin A. EGF-induced trophoblast secretion of MMP-9 and TIMP-1 involves activation of both PI3K and MAPK signalling pathways. Reproduction 2004; 128:355-63. [PMID: 15333786 DOI: 10.1530/rep.1.00234] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Epidermal growth factor (EGF) is present in the maternal-fetal environment and has an important role in placental development. Matrix metalloproteinase-9 (MMP-9) expression/activation is a pre-requisite in extravillous trophoblast invasion. Whereas EGF up-regulates MMP-9 activity in a variety of cell types, there is no direct evidence for the stimulation of MMP-9 and tissue inhibitor of metalloproteinase-1 (TIMP-1) secretion by EGF in extravillous trophoblasts. In addition, the signalling pathways involved in this regulation are not clear. In the present study, we have examined the possible involvement of the phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways in the regulation of the MMP-9/TIMP-1 system by EGF in vitro. We used a well-established invasive extravillous trophoblast cell line (HTR8/Svneo) and measured gene and protein expression by semi-quantitative RT-PCR and western analysis respectively. MMP activity was determined by zymography. We showed for the first time that EGF activated both PI3K/Akt and MAPK/extracellular-signal regulated kinase (ERK) signalling in HTR8/SVneo, and increased both MMP-9 and TIMP-1 mRNAs and protein concentrations. Interfering with either signalling pathway via PI3K inhibitor LY294002 or MEK inhibitor U0126 in EGF-stimulated HTR8/SVneo cells blocked the induction of MMP-9 and TIMP-1. LY294002 inhibited Akt phosphorylation, but had no effect on ERK phosphorylation; U0126 suppressed ERK phosphorylation without interfering with the phosphorylation of Akt. In addition, expression of constitutively active Akt (Myr-Akt1, Myr-Akt2, Myr-Akt3) was not sufficient to induce proMMP-9 and TIMP-1 secretion. Our results suggest that the activation of both PI3K and MAPK pathways in extravillous trophoblasts is necessary for the up-regulation of MMP-9 and TIMP-1 expression by EGF.
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Banerjee R, Rachid Z, Qiu Q, McNamee JP, Tari AM, Jean-Claude BJ. Sustained antiproliferative mechanisms by RB24, a targeted precursor of multiple inhibitors of epidermal growth factor receptor and a DNA alkylating agent in the A431 epidermal carcinoma of the vulva cell line. Br J Cancer 2004; 91:1066-73. [PMID: 15365562 PMCID: PMC2747684 DOI: 10.1038/sj.bjc.6602098] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Recently, with the purpose of enhancing the potency of epidermal growth factor receptor (EGFR)-based therapies, we designed a novel strategy termed ‘Cascade-release targeting’ that seeks to develop molecules capable of degrading to multiple tyrosine kinase (TK) inhibitors and highly reactive electrophiles, in a stepwise fashion. Here we report on the first prototype of this model, RB24, a masked methyltriazene, that in addition to being an inhibitor on its own was designed to degrade to RB14, ZR08, RB10+a DNA alkylating methyldiazonium species. The cascade degradation of RB24 requires the generation of two reactive electrophiles: (a) an iminium ion and (b) a methyldiazonium ion. Thus, we surmise that these species could alkylate the active site of EGFR, thereby irreversibly blocking its action and that DNA damage could be induced by the methyldiazonium. Using the EGFR-overexpressing human epidermoid carcinoma of the vulva cell line, A431, we demonstrate herein that (a) RB24 and its derived species (e.g. RB14, ZR08) irreversibly inhibit EGFR autophosphorylation, (b) RB24 induced significant levels of DNA strand breaks, (c) sustained inhibition of EGFR by RB24 was associated with blockade of MAPK activation and c-fos gene expression, (d) RB24 induced irreversible cell growth inhibition with a 100-fold greater potency than Temodal™, a clinical methyltriazene. The pronounced growth inhibitory potency of RB24 was attributed to its ability to simultaneously damage DNA and irreversibly block EGFR TK activity.
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Qiu Q, Somasundaran P. Complexation between Poly(maleic acid/octyl vinyl ether) and Poly(vinyl caprolactam) in Aqueous Solution and at the Alumina/Water Interface. J Colloid Interface Sci 2002; 253:231-7. [PMID: 16290852 DOI: 10.1006/jcis.2002.8487] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2002] [Accepted: 05/10/2002] [Indexed: 11/22/2022]
Abstract
Solution and interfacial properties of binary polymer mixtures of poly(maleic acid/octyl vinyl ether) (PMAOVE) and poly(vinyl caprolactam) (PVCAP) have been studied for the alumina/water system. To test the hydrophobic effect, mixtures of poly(maleic acid/methyl vinyl ether) (PMAMVE) and PVCAP are also investigated and compared to the behavior of PMAOVE/PVCAP. At low pH, both polymer mixtures become turbid upon mixing. The turbidity increases at low mixing ratios of PVCAP to the vinyl ether component, reaches a maximum, and then decreases at higher mixing ratios. Upon shifting the pH to the alkaline range, i.e., pH 7.5 and above, the turbid solution becomes clear for both the polymer mixtures. Cloud point measurements indicate the absence of complexation of PVCAP with PMAMVE under the alkaline conditions, but strong interaction with PMAOVE. This is attributed to the different forces involved in the complexation among the polymers: H bonding for PVCAP/PMAMVE and both H bonding and hydrophobic effects for PVCAP/PMAOVE. At the alumina/water interface, the normally nonadsorbing PVCAP is triggered to adsorb by PMAOVE, attributed to the hydrophobic complexation between the two. However, the adsorption of PVCAP shows a maximum as a function of the concentration of PMAOVE. At concentrations of PMAOVE above the onset of its own plateau adsorption, the amount of PVCAP triggered to adsorb is reduced possibly due to the polymer complex formation in solution.
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Wang XB, Kakoulidou M, Qiu Q, Giscombe R, Huang D, Pirskanen R, Lefvert AK. CDS1 and promoter single nucleotide polymorphisms of the CTLA-4 gene in human myasthenia gravis. Genes Immun 2002; 3:46-9. [PMID: 11857062 DOI: 10.1038/sj.gene.6363816] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2001] [Revised: 10/02/2001] [Accepted: 10/02/2001] [Indexed: 11/09/2022]
Abstract
The cytotoxic T lymphocyte associated protein 4 (CTLA-4) gene (Ctla-4) is a candidate gene for autoimmune disease. We here report results of two single nucleotide polymorphisms (SNPs) in the Ctla-4, a +49 A/G SNP in CDS1 and a C/T promoter SNP at position -318. There were no differences in these two SNPs between patients and healthy individuals. The frequency of allele G and genotype G/G at position +49 in CDS1 was increased in patients with thymoma when compared with patients with normal and hyperplastic thymic histopathology. Patients with the G/G genotype had signs of immune activation manifested as higher levels of serum IL-1beta and higher percentage of CD28(+) T lymphocytes. There was a strong linkage between the 86bp allele in the 3'-UTR and the A(+49) allele in CDS1. Our results suggest that the SNP at position +49 in CDS1 might be associated with the manifestations of MG.
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Lampe PD, Qiu Q, Meyer RA, TenBroek EM, Walseth TF, Starich TA, Grunenwald HL, Johnson RG. Gap junction assembly: PTX-sensitive G proteins regulate the distribution of connexin43 within cells. Am J Physiol Cell Physiol 2001; 281:C1211-22. [PMID: 11546658 DOI: 10.1152/ajpcell.2001.281.4.c1211] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cells expressing connexin43 are able to upregulate gap junction (GJ) communication by enhancing the assembly of new GJs, apparently through increased connexin trafficking. Because G proteins are known to regulate different aspects of protein trafficking, we examined the effects of pertussis toxin (PTX; a specific inhibitor of certain G proteins) on GJ assembly. Dissociated Novikoff hepatoma cells were reaggregated for 60 min to form nascent junctions. PTX inhibited GJ assembly, as indicated by a reduction in dye transfer. Electron microscopy also revealed a 60% decrease in the number of GJ channels per cell interface. Importantly, PTX blocked the twofold enhancement in GJ assembly found in the presence of low-density lipoprotein. Two G(i alpha) proteins (G(i alpha 2) and G(i alpha 3)), which have been implicated in the control of membrane trafficking, reacted with PTX in ADP-ribosylation studies. PTX and/or the trafficking inhibitors, brefeldin A and monensin, inhibited GJ assembly to comparable degrees. In addition, assays for GJ hemichannels demonstrated reduced plasma membrane levels of connexin43 following PTX treatment. These results suggest that PTX-sensitive G proteins regulate connexin43 trafficking, and, as a result of inhibition with PTX, the number of plasma membrane hemichannels available for GJ assembly is reduced.
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Gruslin A, Qiu Q, Tsang BK. Influence of maternal smoking on trophoblast apoptosis throughout development: possible involvement of Xiap regulation. Biol Reprod 2001; 65:1164-9. [PMID: 11566739 DOI: 10.1095/biolreprod65.4.1164] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Maternal smoking is associated with severe perinatal complications and significant placental pathologies with underlying ultrastructural changes. In this study, we examined the influence of maternal smoking on trophoblast apoptosis throughout development and correlated those findings with changes in expression of X-linked inhibitor of apoptosis protein (Xiap) as well as Fas and Fas ligand (FasL). Trophoblast apoptosis was determined by DNA fragmentation and TUNEL. Protein expression was assessed by Western blotting and immunohistochemistry. Maternal smoking was associated with increased trophoblast apoptosis in the first trimester but decreased trophoblast apoptosis near term. Placental Xiap levels decreased significantly throughout development in nonsmokers (P < 0.05) but remained elevated in smokers. Fas and FasL levels did not vary significantly throughout development nor between groups. However, procaspase-3 levels were significantly increased in smokers at term. Our results suggest that maternal smoking has different effects at different stages of trophoblast differentiation and that this is regulated in part through modulations in placental Xiap expression.
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Qiu Q, Ducheyne P, Gao H, Ayyaswamy P. Formation and differentiation of three-dimensional rat marrow stromal cell culture on microcarriers in a rotating-wall vessel. TISSUE ENGINEERING 2001; 4:19-34. [PMID: 11541090 DOI: 10.1089/ten.1998.4.19] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Using a high aspect ratio vessel (HARV), this study investigated the formation of 3-D rat marrow stromal cell culture on microcarriers and the expression of bone-related biochemical markers under conditions of simulated microgravity. In addition, it calculated the shear stresses imparted on the surface of microcarriers of different densities by the medium fluid in an HARV. Secondary rat marrow stromal cells were cultured on two types of microcarriers, Cytodex-3 beads and modified bioactive glass particles. Examination of cellular morphology by scanning electron microscopy revealed the presence of three-dimensional multicellular aggregates consisting of multiple cell-covered Cytodex-3 microcarriers bridged together. Mineralization was observed in the aggregates. Spherical cell-bead aggregates were observed in an HARV, while cell-bead assemblies were mostly loosely packed in a chain-like or branched structure in a cell bag. The expressions of alkaline phosphatase activity, collagen type I, and osteopontin were shown via the use of histochemical staining, immunolabeling, and confocal scanning electron microscopy. Using a numerical approach, it was found that at a given rotational speed and for a given culture medium, a larger density difference between the microcarrier and the culture medium (e.g., a modified bioactive glass particle) imparted a higher maximum shear stress on the microcarrier.
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