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Mutations in the transforming growth factor beta type II receptor (TGFbetaRII) gene have been detected in several human cancer types exhibiting microsatellite instability. Using intron primers previously reported for examination of the entire coding region of the TGFbetaRII gene, 29 sporadic gastric cancers were screened with non-radioactive single strand conformation polymorphism and subsequent DNA sequencing analysis. Mutations of the TGFbetaRII gene were detected in three out of 29 tumors (10%). Two cases showed deletions in a polyadenine tract in both alleles and was positively associated with replication error. One case had an insertion of GA dinucleotide sequence in one allele. Mutations of the TGFbetaRII gene were restricted to exon 3 and other coding regions were not affected. Loss of heterozygosity was detected by analyzing a polymorphic site in intron 2. Three out of nine (33%) informative cases, which were all of intestinal type and advanced cases, showed loss of heterozygosity but neither TGFbetaRII mutation nor replication error was found in these cases. Immunoreactivity of TGFbetaRII in tumor tissues was reduced to a different extent in the gastric cancer with genetically abnormal transforming growth factor. Although the numbers studied are small, homozygous (A)10 deletion or loss of heterozygosity of TGFbetaRII is involved in tumorigenesis and progression of at least some part of sporadic gastric cancer.   相似文献   
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A 54-year-old man was treated with weekly 24-h infusion of high-dose 5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon cancer. At first, he tolerated the treatment well and no significant toxicity was identified. After a total of eight courses of treatment, a stable disease was observed, but mild shortness of breath was found on occasion. The patient had no previous history of cardiac disease and the heart performance assessed by left ventricular ejection fraction before treatment was normal. Unfortunately, acute pulmonary edema with lethal cardiogenic shock occurred during the ninth course of treatment, in spite of intensive medical treatment. The chest X-ray showed extreme cardiomegaly. Repeated assessment of his heart function by echocardiogram and ventricular ejection fraction revealed a very poor cardiac performance. Toxic cardiogenic shock during weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin is extremely rare. To the best of our knowledge, no case has been reported in the English literature. We report a case and the relevant literature about the incidence, clinical picture and possible pathophysiology on 5-fluorouracil-related cardioxicity is reviewed.   相似文献   
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OBJECTIVE: Recent studies of ovarian cancer have suggested a role for inflammation in carcinogenesis. Data from a population-based case-control study in Hawaii were examined to assess the relation between polymorphisms in cytokines involved with the inflammatory response, specifically members of the interleukin (IL) family and the incidence of ovarian cancer. PATIENTS AND METHODS: The analysis of 182 epithelial ovarian cancer cases and 219 controls focused on the polymorphisms in the following genes: IL-1alpha, IL-1beta, IL-6, IL-10, and IL-18. Genotype data were obtained from blood samples collected in participants' homes, and reproductive, demographic, and lifestyle histories were collected during interview. RESULTS: There were no significant odds ratios (ORs) for ovarian cancer by allelic variants in any of the IL genes after adjusting for age, ethnicity, education, oral contraceptive pill use, pregnancy, and history of tubal ligation. Although there was a significantly reduced risk of ovarian cancer risk among women with an IL-1alpha (-4845) T allele compared to women with two G alleles (OR: 0.59; 95% confidence interval: 0.37-0.97) after adjustment for age and ethnicity, the trend was not significant (p = 0.10). Further examination of the data suggested that women with at least one IL-18 variant allele (a G to C transition at position -137) were at significantly decreased risk of advanced ovarian cancer (OR: 0.51; 95% confidence interval: 0.28-0.90) compared to women with the IL-18 GG genotype. There was a significant difference in the risk of ovarian cancer associated with the IL-18 C allele by stage at diagnosis (p = 0.04 for homogeneity in the ORs): cases with IL-18 GC or CC genotypes were less likely to be diagnosed at regional/distant stages. Analysis of the data within ethnic subgroups revealed a significant positive association of the heterozygous IL-18 GC genotype with ovarian cancer risk among Native Hawaiian women (OR: 9.96; 95% CI: 1.88-52.90). The OR for ovarian cancer was not significant for Native Hawaiian women homozygous for the IL-18 C allele, but only one case and control had the IL-18 CC genotype. CONCLUSIONS: Overall, this study does not support an association of selected IL-1alpha, IL-1beta, IL-6, IL-10, or IL-18 polymorphisms with the risk for ovarian cancer. However, the IL-18 G137C variant may be a marker for ovarian cancer progression or metastasis.  相似文献   
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Ethics codes and guidelines date back to the origins of medicine in virtually all civilizations. Developed by the medical practitioners of each era and culture, oaths, prayers, and codes bound new physicians to the profession through agreement with the principles of conduct toward patients, colleagues, and society. Although less famous than the Hippocratic oath, the medical fraternities of ancient India, seventh-century China, and early Hebrew society each had medical oaths or codes that medical apprentices swore to on professional initiation. The Hippocratic oath, which graduating medical students swear to at more than 60% of US medical schools, is perhaps the most enduring medical oath of Western civilization. Other oaths commonly sworn to by new physicians include the Declaration of Geneva (a secular, updated form of the Hippocratic oath formulated by the World Medical Association, Ferney-Voltaire, France) and the Prayer of Moses Maimondes, developed by the 18th-century Jewish physician Marcus Herz.  相似文献   
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PURPOSE: This randomized study compared the results achieved by concurrent chemoradiotherapy (CRT) versus radiotherapy (RT) alone for nasopharyngeal carcinoma (NPC) with advanced nodal disease. PATIENTS AND METHODS: Patients with nonkeratinizing/undifferentiated NPC staged T1-4N2-3M0 were randomized to CRT or RT. Both arms were treated with the same RT technique and dose fractionation. The CRT patients were given cisplatin 100 mg/m2 on days 1, 22, and 43, followed by cisplatin 80 mg/m2 and fluorouracil 1,000 mg/m2/d for 96 hours starting on days 71, 99, and 127. RESULTS: From 1999 to January 2004, 348 eligible patients were randomly assigned; the median follow-up was 2.3 years. The two arms were well-balanced in all prognostic factors and RT parameters. The CRT arm achieved significantly higher failure-free survival (72% v 62% at 3-year, P = .027), mostly as a result of an improvement in locoregional control (92% v 82%, P = .005). However, distant control did not improve significantly (76% v 73%, P = .47), and the overall survival rates were almost identical (78% v 78%, P = .97). In addition, the CRT arm had significantly more acute toxicities (84% v 53%, P < .001) and late toxicities (28% v 13% at 3-year, P = .024). CONCLUSION: Preliminary results confirmed that CRT could significantly improve tumor control, particularly at locoregional sites. However, there was significant increase in the risk of toxicities and no early gain in overall survival. Longer follow-up is needed to confirm the ultimate therapeutic ratio.  相似文献   
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Clinical trials of Treg therapy in transplantation are currently entering phases IIa and IIb, with the majority of these employing polyclonal Treg populations that harbor a broad specificity. Enhancing Treg specificity is possible with the use of chimeric antigen receptors (CARs), which can be customized to respond to a specific human leukocyte antigen (HLA). In this study, we build on our previous work in the development of HLA-A2 CAR-Tregs by further equipping cells with the constitutive expression of interleukin 10 (IL-10) and an imaging reporter as additional payloads. Cells were engineered to express combinations of these domains and assessed for phenotype and function. Cells expressing the full construct maintained a stable phenotype after transduction, were specifically activated by HLA-A2, and suppressed alloresponses potently. The addition of IL-10 provided an additional advantage to suppressive capacity. This study therefore provides an important proof-of-principle for this cell engineering approach for next-generation Treg therapy in transplantation.  相似文献   
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