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101.
Enhancement of paclitaxel-induced microtubule stabilization, mitotic arrest, and apoptosis by the microtubule-targeting agent EM012 总被引:3,自引:0,他引:3
EM012, a semisynthetic phthalideisoquinoline alkaloid, has been recently found to target microtubules and possess anti-cancer activity. In this study, we evaluated the effects of EM012 in combination with the classic microtubule-targeting agent paclitaxel. Our results demonstrated that EM012 enhanced the anti-proliferative activity of nanomolar concentrations of paclitaxel in human breast cancer (MCF7), prostate cancer (DU145), and non-small-cell lung cancer (A549) cells. Further studies revealed that EM012 increased the ability of nanomolar concentrations of paclitaxel to induce mitotic arrest and apoptosis, without affecting microtubule polymerization. In contrast, when micromolar concentrations of paclitaxel were used, EM012 promoted paclitaxel-induced microtubule polymerization both in vitro and in cultured cells. Nevertheless, EM012 enhanced the ability of nanomolar concentrations of paclitaxel to stabilize microtubules, as indicated by increased tubulin acetylation. Our results therefore suggest a therapeutic potential of EM012/paclitaxel combination in the management of human cancer and provide mechanistic insights into the combined effects of these two microtubule-targeting agents. 相似文献
102.
Sridevi K Neena K Chitralekha KT Arif AK Tomar D Rao DN 《International immunopharmacology》2004,4(1):1-14
In leprosy, cell-mediated immunity (CMI) is more significant than humoral response to eliminate intracellular pathogen. T cell defect is a common feature in lepromatous leprosy (LL) patients as compared to tuberculoid type (TT) patients. For efficient initiation of CD4+, T cell response requires T cell receptor (TCR) activation and costimulation provided by molecules on antigen-presenting cells (APC) and their counter receptors on T cells. In our previous study, the defective T cell function in LL patients was restored to a proliferating state with the release of TH1 type cytokines using mycobacterial antigen(s) with two immunomodulators (Murabutide (MDP-BE) and T cell epitope of Trat protein of Escherichia coli) by presenting the antigen in particulate form in vitro to PBMC derived from leprosy patients. This observation prompted us to study the expression of the costimulatory molecules (CD80, CD86, CD28, CD152), other accessory molecules (TCR alphabeta/gammadelta) and T cell lineage molecules (CD4+ and CD8+) during constitutive and activated state of peripheral blood mononuclear cells (PBMC) derived from normal and leprosy individuals using different formulations of Mycobacterium leprae total cell wall antigen (MLCWA), Trat and MDP-BE using flow cytometric analysis. An increased surface expression of CD80, CD86 and CD28 but decreased CD152 expression was observed when PBMC of normal, BT/TT (tuberculoid) and BL/LL (lepromatous) patients were stimulated in vitro with MLCWA+MDP-BE+Trat peptide using liposomal mode of antigen delivery, while opposite results were obtained with the antigen alone. Antibody inhibition study using antihuman CD80 or CD86 completely abolished the T cell lymphoproliferation, thereby reconfirming the importance of these costimulatory molecules during T cell activation/differentiation. Though the liposome-entrapped antigen formulation has no effect on expression of alphabeta/gammadelta T cell receptor, the constitutive levels of TCR gammadelta were high in lepromatous patients. Thus, TCR bearing gammadelta appears to have a negligible regulatory role in peripheral blood of leprosy patients. The percentage of cells positive for CD4+ are increased in inducible state in all the three groups, while CD8+-positive cells were decreased in LL patients, thereby reconfirming the fact that priming of CD4+ cells are necessary for producing final effector functions. Lastly, intracellular cytokine staining experiment indicated that CD4+ cells are the major producers of IFN-gamma but not NK cells. The study highlights the reversal of T cell anergy especially in lepromatous patients through the modulation of costimulatory molecule expression under the influence of Th1 cytokines, i.e., IL-2 and IFNgamma. 相似文献
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An unusual case of massive cystic degeneration in an uterine leiomyoma measuring 21 cm in diameter, in a 40 year old female is being presented. It was diagnosed as a cystic adnexal tumor on ultrasonogram. Interlacing bundles of smooth muscle were identified in the cyst wall, which was confirmed on special stains. The differential diagnoses considered in this case are discussed. To the best of our knowledge, this is the largest cystic degeneration in an uterine leiomyoma reported in the literature. 相似文献
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Walsh MM Hilton JF Ellison JA Gee L Chesney MA Tomar SL Ernster VL 《Addictive behaviors》2003,28(6):1095-1113
OBJECTIVE: To determine the efficacy of a spit tobacco (ST) intervention designed to promote ST cessation and discourage ST initiation among male high school baseball athletes. METHODS: This study was a cluster-randomized controlled trial. Forty-four randomly selected high schools in rural California were randomized within strata (prevalence of ST use and number and size of baseball teams) to either the intervention or the control group. Ninety-three percent of eligible baseball athletes participated, yielding 516 subjects in 22 intervention schools and 568 subjects in 22 control schools. Prevalences of sustained ST cessation and ST use initiation over 1 year were assessed by self-report. Multivariate logistic regression models for clustered responses were used to test the null hypotheses of no association between group and the two outcomes, adjusted for the stratified design and baseline imbalances between groups in significant predictors of ST use. RESULTS: Prevalence of cessation was 27% in intervention high schools and 14% in control high schools (odds ratio (OR)=2.29; 95% confidence interval (CI), 1.36-3.87). The intervention was especially effective in promoting cessation among those who, at baseline, lacked confidence that they could quit (OR=6.4; 95% CI, 1.0-4.3), among freshmen (OR=15; 95% CI, 0.9-260), and among nonsmokers (OR=3.2; 95% CI, 0.9-11). There was no significant difference between groups in the prevalence of ST initiation. CONCLUSIONS: This intervention was effective in promoting ST cessation, but was ineffective in preventing initiation of ST use by nonusers. 相似文献
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OBJECTIVE: This study compared yearly dental visits of diabetic adults with those of nondiabetic adults. For adults with diabetes, we compared the frequency of past-year dental visits with past-year visits for diabetes care, dilated eye examinations, and foot examinations. RESEARCH DESIGN AND METHODS: We conducted a cross-sectional study using a sample of 105,718 dentate individuals aged > or =25 years, including 4,605 individuals with diabetes who participated in the 1995-1998 Behavioral Risk Factor Surveillance System in 38 states. RESULTS: Dentate adults (i.e., those with at least some natural teeth) with diabetes were less likely than those without diabetes to have seen a dentist within the preceding 12 months (65.8 vs. 73.1%, P = 0.0000). Adults with diabetes were less likely to have seen a dentist than to have seen a health care provider for diabetes care (86.3%); the percentage who saw a dentist was comparable with the percentage who had their feet examined (67.7%) or had a dilated eye examination (62.3%). The disparity in dental visits among racial or ethnic groups and among socioeconomic groups was greater than that for any other type of health care visit for subjects with diabetes. CONCLUSIONS: Promotion of oral health among diabetic patients may be necessary, particularly in Hispanic and African-American communities. Information on oral health complications should be included in clinical training programs. Oral and diabetes control programs in state health departments should collaborate to promote preventive dental services, and the oral examination should be listed as a component of continuous care in the American Diabetes Association's standards of medical care for diabetic patients. 相似文献