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991.
992.
Blaga R Durand B Antoniu S Gherman C Cretu CM Cozma V Boireau P 《The American journal of tropical medicine and hygiene》2007,76(5):983-986
According to the International Commission on Trichinellosis survey in 2004, Romania has the most cases of trichinellosis in the world. Epidemiologic data for each county were collected and analyzed from two different time periods: before (1980-1989) and after (1990-2004) political changes. Data were analyzed separately for Transylvania and the rest of the Romanian counties. During the past 25 years, 28,293 human cases of trichinellosis were reported with an incidence of 51.0 cases per 10(6) persons per year. An important increase in the incidence was observed from 1980 to 1989 compared with the 1990-2004 period. For the entire period, the incidence rate obtained for Transylvanian counties (82.2 cases per 10(6) persons per year) was higher than the incidence rate obtained for the other counties (35.7 cases per 10(6) persons per year). Hypotheses and facts contributing to the heterogeneity of human trichinellosis cases are discussed. 相似文献
993.
Activation of PPARdelta inhibits cardiac fibroblast proliferation and the transdifferentiation into myofibroblasts 总被引:1,自引:0,他引:1
Teunissen BE Smeets PJ Willemsen PH De Windt LJ Van der Vusse GJ Van Bilsen M 《Cardiovascular research》2007,75(3):519-529
OBJECTIVE: The development of heart failure is invariably associated with extensive fibrosis. Treatment with Peroxisome Proliferator-Activated Receptor (PPAR) ligands has been shown to attenuate cardiac fibrosis, but the molecular mechanism underlying this protective effect has remained largely unknown. In this study the potential of each PPAR isoform (PPARalpha, delta, and gamma) to attenuate cardiac fibroblast proliferation, fibroblast (CF) to myofibroblast (CMF) transdifferentiation, and collagen synthesis was investigated. METHODS AND RESULTS: PPARdelta was found to be the most abundant isoform in both CF and CMF. Only the PPARdelta ligand GW501516, but not PPARalpha ligand Wy-14,643 or PPARgamma ligand rosiglitazone, significantly increased PPAR-dependent promoter activity and expression of the PPAR-responsive gene UCP2 ( approximately 5-fold). GW501516 reduced the proliferation rate of CF (-38%) and CMF (-26%), which was associated with increased expression of the cell cycle inhibitor gene G0/G1 switch gene 2 (G0S2). Exposure of CF to the PPARdelta ligand or adenoviral overexpression of PPARdelta significantly decreased alpha-smooth muscle actin (alpha-SMA) levels, indicating a reduced CF to CMF transition. The inhibition of transdifferentiation by PPARdelta correlated with an increase in PTEN (Phosphatase and Tensin Homolog Deleted on Chromosome ten) expression. (3)H-Proline incorporation assays demonstrated a GW501516 induced decline in collagen synthesis (-36%) in CF. CONCLUSION: Cardiac fibroblast proliferation, fibroblast to myofibroblast differentiation and collagen synthesis were reduced after activation of PPARdelta, suggesting that PPARdelta represents an attractive molecular target for attenuating cardiac fibrosis. 相似文献
994.
Attenuation of myocardial reperfusion injury in pigs by Mirococept, a membrane-targeted complement inhibitor derived from human CR1 总被引:1,自引:0,他引:1
Banz Y Hess OM Robson SC Csizmadia E Mettler D Meier P Haeberli A Shaw S Smith RA Rieben R 《Cardiovascular research》2007,76(3):482-493
OBJECTIVES: Membrane-targeted application of complement inhibitors may ameliorate ischemia/reperfusion (I/R) injury by directly targeting damaged cells. We investigated whether Mirococept, a membrane-targeted, myristoylated peptidyl construct derived from complement receptor 1 (CR1) could attenuate I/R injury following acute myocardial infarction in pigs. METHODS: In a closed-chest pig model of acute myocardial infarction, Mirococept, the non-tailed derivative APT154, or vehicle was administered intracoronarily into the area at risk 5 min pre-reperfusion. Infarct size, cardiac function and inflammatory status were evaluated. RESULTS: Mirococept targeted damaged vasculature and myocardium, significantly decreasing infarct size compared to vehicle, whereas APT154 had no effect. Cardioprotection correlated with reduced serum troponin I and was paralleled by attenuated local myocardial complement deposition and tissue factor expression. Myocardial apoptosis (TUNEL-positivity) was also reduced with the use of Mirococept. Local modulation of the pro-inflammatory and pro-coagulant phenotype translated to improved left ventricular end-diastolic pressure, ejection fraction and regional wall motion post-reperfusion. CONCLUSIONS: Local modification of a pro-inflammatory and pro-coagulant environment after regional I/R injury by site-specific application of a membrane-targeted complement regulatory protein may offer novel possibilities and insights into potential treatment strategies of reperfusion-induced injury. 相似文献
995.
996.
Nectin-4 is a new histological and serological tumor associated marker for breast cancer 总被引:1,自引:0,他引:1
Stéphanie Fabre-Lafay Florence Monville Sarah Garrido-Urbani Carole Berruyer-Pouyet Christophe Ginestier Nicolas Reymond Pascal Finetti Richard Sauvan José Adélaïde Jeannine Geneix Eric Lecocq Cornel Popovici Patrice Dubreuil Patrice Viens Anthony Gonçalves Emmanuelle Charafe-Jauffret Jocelyne Jacquemier Daniel Birnbaum Marc Lopez 《BMC cancer》2007,7(1):1-16
Introduction
Breast cancer is a complex and heterogeneous disease at the molecular level. Evolution is difficult to predict according to classical histoclinical prognostic factors. Different studies highlight the importance of large-scale molecular expression analyses to improve taxonomy of breast cancer and prognostic classification. Identification of new molecular markers that refine this taxonomy and improve patient management is a priority in the field of breast cancer research. Nectins are cell adhesion molecules involved in the regulation of epithelial physiology. We present here Nectin-4/PVRL4 as a new histological and serological tumor associated marker for breast carcinoma.Methods
Expression of Nectin-4 protein was measured on a panel of 78 primary cells and cell lines from different origins and 57 breast tumors by FACS analysis and immunohistochemistry (IHC), respectively. mRNA expression was measured by quantitative PCR. Serum Nectin-4 was detected by ELISA and compared with CEA and CA15.3 markers, on panels of 45 sera from healthy donors, 53 sera from patients with non-metastatic breast carcinoma (MBC) at diagnosis, and 182 sera from patients with MBC. Distribution of histological/serological molecular markers and histoclinical parameters were compared using the standard Chi-2 test.Results
Nectin-4 was not detected in normal breast epithelium. By contrast, Nectin-4 was expressed in 61% of ductal breast carcinoma vs 6% in lobular type. Expression of Nectin-4 strongly correlated with the basal-like markers EGFR, P53, and P-cadherin, and negatively correlated with the luminal-like markers ER, PR and GATA3. All but one ER/PR-negative tumors expressed Nectin-4. The detection of Nectin-4 in serum improves the follow-up of patients with MBC: the association CEA/CA15.3/Nectin-4 allowed to monitor 74% of these patients compared to 67% with the association CEA/CA15.3. Serum Nectin-4 is a marker of disease progression, and levels correlate with the number of metastases (P = 0.038). Serum Nectin-4 is also a marker of therapeutic efficiency and correlates, in 90% of cases, with clinical evolution.Conclusion
Nectin-4 is a new tumor-associated antigen for breast carcinoma. Nectin-4 is a new bio-marker whose use could help refine breast cancer taxonomy and improve patients' follow-up. Nectin-4 emerges as a potential target for breast cancer immunotherapy. 相似文献997.
Aneuploidy acts both oncogenically and as a tumor suppressor 总被引:6,自引:0,他引:6
An abnormal chromosome number, aneuploidy, is a common characteristic of tumor cells. Boveri proposed nearly 100 years ago that aneuploidy causes tumorigenesis, but this has remained untested due to the difficulty of selectively generating aneuploidy. Cells and mice with reduced levels of the mitosis-specific, centromere-linked motor protein CENP-E are now shown to develop aneuploidy and chromosomal instability in vitro and in vivo. An increased rate of aneuploidy does drive an elevated level of spontaneous lymphomas and lung tumors in aged animals. Remarkably, however, in examples of chemically or genetically induced tumor formation, an increased rate of aneuploidy is a more effective inhibitor than initiator of tumorigenesis. These findings reveal a role of aneuploidy and chromosomal instability in preventing tumorigenesis. 相似文献
998.
999.
Pascal Sève Raymond Lai Keyue Ding Timothy Winton Charles Butts John Mackey Charles Dumontet Laith Dabbagh Sarit Aviel-Ronen Lesley Seymour Marlo Whitehead Ming-Sound Tsao Frances A Shepherd Tony Reiman 《Clinical cancer research》2007,13(3):994-999
PURPOSE: High class III beta-tubulin (bTubIII) expression in advanced non-small cell lung cancer is known to correlate with reduced response rates and inferior survival with anti-microtubule agents. JBR.10 showed a 12% and 15% improvement in 5-year recurrence-free survival (RFS) and overall survival (OS), respectively, with the addition of cisplatin and vinorelbine following resection of stage IB-II non-small cell lung cancer. We sought to determine the effect of bTubIII on patient outcome and benefit from adjuvant chemotherapy in the JBR.10 trial. EXPERIMENTAL DESIGN: We did a semiquantitative immunohistochemical assay for bTubIII on primary tumor tissue available from 265 of the 482 patients in JBR.10. Tumors were classified as bTubIII "low" or "high" using a validated method. We examined the prognostic effect of bTubIII in patients treated with or without chemotherapy and the survival benefit from chemotherapy in low versus high bTubIII subgroups. RESULTS: High bTubIII expression was associated with poorer RFS and OS in patients treated with surgery alone but not in patients treated with adjuvant chemotherapy. The RFS and OS benefits of adjuvant chemotherapy were greater in high versus low tubulin expressors. However, with Cox regression, the interaction between bTubIII status and chemotherapy treatment in predicting RFS or OS did not reach statistical significance. CONCLUSIONS: Chemotherapy seemed to overcome the negative prognostic effect of high bTubIII expression. Greater benefit from adjuvant chemotherapy was seen in patients with high bTubIII expression. This is contrary to what has been seen in the setting of advanced disease; possible reasons for this difference are being explored. 相似文献
1000.
Bonnevie L Bel A Sabbah L Al Attar N Pradeau P Weill B Le Deist F Bellamy V Peyrard S Ménard C Desnos M Bruneval P Binder P Hagège AA Pucéat M Menasché P 《Transplantation》2007,83(3):333-335
To test the purported immune privilege of embryonic stem cells (ESC) in the challenging setting of xenotransplantation, 14 immunocompetent baboons were subjected to a coronary artery occlusion-reperfusion sequence and, two weeks later, randomized to receive in-scar injections of culture medium or cardiac-committed mouse ESC engineered to express fluorescent reporter genes driven by cardiac-specific promoters. Two months after transplantation, left ventricular function, as assessed by echocardiography, deteriorated to a similar extent in control and treated baboons. This correlated with failure to identify the grafted cells by X-gal histology and immunofluorescence. Rejection did not seem to be mediated by xenoantibodies, but rather by T lymphocytes and natural killer cells as suggested by positive immunostaining for CD3 and CD56 early after transplantation. There was no increase in circulating levels of regulatory T cells. These data raise a cautionary note about the immune privilege of ESC and suggest that from a mere immunologic standpoint, ESC xenotransplantation is likely to be an unrealistic challenge. 相似文献