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71.
The T393C polymorphism of the G alpha s gene (GNAS1) is a novel prognostic marker in bladder cancer. 总被引:2,自引:0,他引:2
Ulrich H Frey Andreas Eisenhardt Gerd Lümmen Herbert Rübben Karl-Heinz J?ckel Kurt W Schmid Winfried Siffert 《Cancer epidemiology, biomarkers & prevention》2005,14(4):871-877
The G protein G(alpha)s pathway is linked to proapoptotic signaling in cancer cell lines. To assess the role of the GNAS1 locus encoding G(alpha)s as a genetic factor for disease progression of transitional cell carcinoma (TCC) of the bladder, we genotyped the synonymous T393C polymorphism in 254 patients with TCC (minor allele frequency: 0.43) to examine a potential association between genotypes and disease progression. Using Kaplan-Meier estimates to calculate 5-year probabilities of follow-up, we could show that progression-free survival, metastasis-free survival, and cancer-specific survival was significantly increased in TT genotypes (56%, 84%, 82%) compared with CC genotypes (35%, 53%, 58%). In multivariate Cox proportional hazard analysis, the T393C polymorphism was an independent prognostic factor for clinical outcome. Homozygous CC patients were at highest risk for progression [odds ratio (OR), 1.94; P = 0.020], metastasis (OR, 3.49; P = 0.005), and tumor-related death (OR, 2.49; P = 0.031) compared with TT genotypes. Heterozygous patients had an intermediate risk compatible with a gene-dose effect. Real-time PCR analysis of urothelial tumor tissue as well as adipose and heart tissue revealed that G(alpha)s mRNA expression was highest in TT genotypes, indicating a proapoptotic effect in these genotypes. In conclusion, the GNAS1 T393C status associated with differential G(alpha)s mRNA expression is a novel independent prognostic marker for clinical outcome supporting a functional role of G(alpha)s in bladder cancer progression. 相似文献
72.
Osteosarcoma relapse after combined modality therapy: an analysis of unselected patients in the Cooperative Osteosarcoma Study Group (COSS). 总被引:4,自引:0,他引:4
Beate Kempf-Bielack Stefan S Bielack Heribert Jürgens Detlev Branscheid Wolfgang E Berdel G Ulrich Exner Ulrich G?bel Knut Helmke Gernot Jundt Hartmut Kabisch Mathias Kevric Thomas Klingebiel Rainer Kotz Rainer Maas Rudolf Schwarz Michael Semik J?rn Treuner Andreas Zoubek Kurt Winkler 《Journal of clinical oncology》2005,23(3):559-568
PURPOSE: To evaluate the impact of patient, tumor, and treatment-related factors on outcome in unselected patients with recurrent osteosarcoma. PATIENTS AND METHODS: Five hundred seventy-six consecutive patients who had achieved a first complete surgical remission (CR) during combined-modality therapy on neoadjuvant Cooperative Osteosarcoma Study Group (COSS) protocols and then developed recurrent osteosarcoma were analyzed (median time from biopsy to relapse, 1.6 years; range, 0.1 to 14.3 years). There were 501 patients with metastases, 44 with local recurrences, and 31 with both. Metastases involved lungs (469 patients), bones (90 patients), and/or other sites (54 patients). RESULTS: After a median follow-up of 1.2 years for all patients and 4.2 years for survivors, actuarial overall survival (OS) rates at 2, 5, and 10 years were 0.38, 0.23, and 0.18, respectively. Five-year OS was 0.39 for 339 patients with and 0.00 for 229 patients without a second surgical CR (P < .0001). A long time to relapse, a solitary lesion, and, in the case of pulmonary metastases, unilateral disease and the absence of pleural disruption, were of positive prognostic value in uni- and multivariate analyses, as were a second surgical CR and the use of second-line chemotherapy. Radiotherapy was associated with moderately prolonged survival in patients without a second CR. The very limited prognostic differences associated with the use of second-line chemotherapy appeared to be more pronounced with polychemotherapy. CONCLUSION: Time to relapse and tumor burden correlate with postrelapse outcome in osteosarcoma. Complete surgery is an essential component of curative second-line therapy. Chemotherapy, particularly chemotherapy with more than one agent, may contribute to limited improvements in outcome. 相似文献
73.
Donald J Buchsbaum M B Khazaeli Donald B Axworthy Jody Schultz Tandra R Chaudhuri Kurt R Zinn Mark Carpenter Albert F LoBuglio 《Clinical cancer research》2005,11(22):8180-8185
PURPOSE: This study examined a pretarget radioimmunotherapy strategy for treatment of an i.p. tumor model (LS174T). EXPERIMENTAL DESIGN: The strategy used regional administration (i.p.) of a novel targeting molecule composed of four CC49 anti-tumor-associated glycoprotein 72 (TAG-72) single-chain antibodies linked to streptavidin as a fusion protein (CC49 fusion protein); 24 hours later, a synthetic clearing agent was administered i.v. to produce hepatic clearance of unbound CC49 fusion protein/synthetic clearing agent complexes. Four hours later, a low molecular weight radiolabeled reagent composed of biotin conjugated to the chelating agent 7,10-tetra-azacyclododecane-N,N',N',N'-tetraacetic acid (DOTA) complexed with (111)In-, (90)Y-, or (177)Lu-DOTA-biotin was injected. RESULTS: Radiolocalization to tumor sites was superior with i.p. administration of radiolabeled DOTA-biotin as compared with i.v. administration. Imaging and biodistribution studies showed excellent tumor localization of radioactivity with (111)In- or (177)Lu-DOTA-biotin. Tumor localization of (111)In-DOTA-biotin was 43% ID/g and 44% ID/g at 4 and 24 hours with the highest normal tissue localization in the kidney with 6% ID/g at 48 and 72 hours. Therapy studies with (90)Y-DOTA-biotin at doses of 400 to 600 microCi or (177)Lu-DOTA-biotin at doses of 600 to 800 microCi produced significant prolongation of survival compared with controls (P = 0.03 and P < 0.01). CONCLUSIONS: Pretarget radioimmunotherapy using regional administration of CC49 fusion protein and i.p. (90)Y- or (177)Lu-DOTA-biotin represents a successful therapeutic strategy in the LS174T i.p. tumor model and this strategy may be applicable to human trials in patients with i.p. ovarian cancer. 相似文献
74.
目的 探讨吡格列酮(PGZ)对人神经胶质瘤细胞株SNB19增殖和凋亡的影响及其机制。方法 用MTT、流式细胞仪、Tunel和Western blot分析技术。结果 吡格列酮能够抑制SNB19细胞增殖和诱导其凋亡,同时伴有Bax表达的增高和pRb、Bcl-2表达的降低。结论 PGZ能够在体外抑制胶质瘤SNB19细胞的生长并诱导其凋亡,提示PGZ有可能成为一种新的治疗胶质瘤药物。 相似文献
75.
Kurt B Stevenson Matthew Samore James Barbera Elizabeth Hannah James W Moore Julie L Gerberding Peter Houck 《American journal of health-system pharmacy》2004,61(8):787-792
PURPOSE: Pharmacist involvement in antimicrobial use at small rural hospitals in four Western states was studied. METHODS: Surveys were mailed in July 2000 to hospitals with a daily patient census of <150 in Idaho, Nevada, Utah, and eastern Washington. RESULTS: Seventy-seven (77%) of 100 hospitals returned completed surveys. Only 5% of the hospitals had onsite pharmacists 24 hours per day. An onsite pharmacist was present for a median of 26 hours per week in hospitals without 24-hour pharmacist coverage (range, 0-116 hr/wk). Many hospitals (71%) had policies for monitoring or controlling antimicrobial use, but only 28% had a system capable of monitoring compliance with such policies. Few hospitals had systems for recommending changes in antimicrobial selection on the basis of susceptibility test results (27%) or for monitoring physician compliance with dosage recommendations by pharmacists (21%). Onsite pharmacist hours were significantly associated with pharmacists being involved in the initial ordering of antibiotics and providing active oversight of antimicrobial use. There was a negative correlation between onsite pharmacist hours and use of third-generation cephalosporins and carbapenems. CONCLUSION: A survey showed that rural hospital pharmacists in four Western states spent relatively little time monitoring and influencing antimicrobial prescribing. 相似文献
76.
Humam M Kehrli T Jeannerat D Muñoz O Hostettmann K Christen P 《Journal of natural products》2011,74(1):50-53
Three tropane alkaloids, named schizanthines N, O, and P (1-3), have been isolated from the crude alkaloid extract of the endemic Chilean plant Schizanthus tricolor. On the basis of extensive NMR studies and MS fragmentation analysis, their structures were determined to be 3α-(E)-4-hydroxysenecioyloxy-6β-angeloyloxytropane (1), 3α-(E)-4-hydroxysenecioyloxy-6β-senecioyloxytropane (2), and 3α-mesaconyloxy-6β-senecioyloxytropane (3). Compounds 1 and 2 are the first isomeric alkaloids in the tropane series possessing a hydroxysenecioyl substituent as an esterifying moiety. 相似文献
77.
Queiroz EF Atindehou KK Terreaux C Antus S Hostettmann K 《Journal of natural products》2002,65(3):403-406
Four new prenylated isoflavonoids, vogelins D-G (1-4), were isolated from the CH2Cl2 extract of Erythrina vogelii root bark in addition to the known compounds isolupalbigenin (5), ficuisoflavone (6), ulexone (7), isochandalon (8), and isoderrone (9). The structures 1-4 were elucidated by spectroscopic and chemical methods. The absolute configuration of compound 1 was determined on the basis of its CD spectrum. Possible biogenetic relationships among the E. vogelii isoflavonoids are briefly discussed. 相似文献
78.
Barnhart KT Rinaudo P Hummel A Pena J Sammel MD Chittams J 《Fertility and sterility》2003,80(6):1345-1351
OBJECTIVE: The diagnosis of ectopic pregnancy (EP) is often confirmed at presentation (acute), but often requires serial beta-hCG levels to confirm the diagnosis (chronic). The purpose of this study is to analyze whether these clinical presentations represent a spectrum of disease. DESIGN: The retrospective cohort study of 452 patients diagnosed with EP at the University of Pennsylvania in the years 1990-1999. SETTING: University of Pennsylvania, Philadelphia, Pennsylvania. PATIENT(S): Four hundred fifty-two patients diagnosed with EP. Patients diagnosed with EP were divided into two groups according to the time of diagnosis. MAIN OUTCOME MEASURE(S): A total of 37 parameters were examined including historic and demographic factors, findings at presentation, and treatment and outcome variables. RESULT(S): The two groups were similar in terms of historic EP risk factors. Multivariable analysis demonstrates that women with a chronic presentation were less likely to have received fertility medications (odds ratio [OR] 0.23; 95% confidence interval [CI] 0.06-0.84), less likely to present with pain (OR 0.29; 95% CI 0.12-0.71), have a lower beta-hCG level at presentation (9,849 mIU/mL +/- 16,726 vs. 1,787 mIU/mL +/- 4,717), lower chance of rupture (OR 0.19; 95% CI 0.05-0.73), and less frequently have blood type 0. CONCLUSION(S): Women diagnosed with ectopic pregnancy can be categorized into two groups, those with an acute presentation and those with a chronic presentation. Differences in risk factors, presentation, and outcome may reflect differences in trophoblast viability or invasive potential. 相似文献
79.
80.