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81.
Whereas cancer patients have benefited from liquid biopsies, the scenario for gastric adenocarcinoma (GAC) is still dismal. We used next-generation deep sequencing of TP53—a highly mutated and informative gene in GAC—to assess mutations in tumor biopsies, plasma (PL) and stomach fluids (gastric wash—GW). We evaluated their potential to reveal tumor-derived mutations, useful for monitoring mutational dynamics at diagnosis, progression and treatment. Exon-capture libraries were constructed from 46 patients including tumor biopsies, GW and PL pre and post-treatment (196 samples), with high vertical coverage >8,000×. At diagnosis, we detected TP53 mutations in 15/46 biopsies (32.6%), 7/46 GW- (15.2%) and 6/46 PL-samples (13%). Biopsies and GW were concordant in 38/46 cases (82.6%) for the presence/absence of mutations and, furthermore, four GW-exclusive mutations were identified, suggesting tumor heterogeneity. Considering the combined analysis of GW and PL, TP53 mutations found in biopsies were also identified in 9/15 (60%) of cases, the highest detection level reported for GAC. Our study indicates that GW could be useful to track DNA alterations, especially if anchored to a comprehensive gene-panel designed for this malignancy.  相似文献   
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To investigate the prognostic value of multiple genetic alterations, individual molecular tumor profiles were established in 79 sporadic colorectal carcinomas (41 stage II and 38 stage III). Tumors were analyzed for allelic loss (LOH) and genetic instability (MSI) using 14 microsatellites intragenic to or associated with tumor suppressor or DNA mismatch repair genes. Molecular profiling identified tumors with LOH at multiple loci without microsatellite instability (MSS), tumors with high levels of LOH and low level microsatellite marker instability (MSI-L), and tumors with high levels of MSI (MSI-H), but rare LOH. K-ras mutations occurred more frequently in MSS/MSI-L carcinomas (26%) than in MSI-H colorectal tumors (10%), the latter showing a high frequency of TGFbeta type II frameshift mutations (82%). Correlation of molecular and clinical data revealed a better prognosis for stage III tumor patients displaying 5q12 loss rather than retention of heterozygosity. Thus, molecular profiling allows the identification of new prognostic markers and might facilitate the stratification of colorectal cancer patients.  相似文献   
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Peptic ulcer due to Zollinger-Ellison syndrome is a rare entity. In this case report a 55-year-old man had a medical history of esophageal reflux, vomiting, and diarrhea for 10 years. Despite continuous medication with a proton pump inhibitor, no complete recovery from symptoms was achieved. A diagnosis of gastrinoma was at first not considered. After discontinuation of the proton pump inhibitor for only a few days, the strong stimulation of the gastrinoma led to fulminant hydrochloric acid burn of the distal esophagus with iatrogenic or spontaneous perforation at the esophagogastral junction. We describe the operative treatment as a two-stage reconstruction with colon interposition and resection of the primary tumor in the duodenum.  相似文献   
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Higher throughput methods, high content analysis and automated screening methods are of highest demand in drug development today. In toxicology, these strategies are becoming increasingly important, as well. Therefore, an integrated higher throughput method for the comet assay is addressed by the development presented here.The sensitivity, specificity and relevance of the comet assay as a method for determination of DNA damage in vivo and in vitro have been highlighted in many studies. Actually, efforts are made to include it in a panel of genotoxicity tests for regulatory purposes. However, the standard comet assay is a time consuming procedure due to the specific methods needed. The improvements presented here lead to a faster and easier slide-production, a smaller amount of cells needed, a higher amount of comets quantified, a fully automated analysis of comets including reanalysis, storing, visualisation and documentation possibilities using standard comet quantification models such as tail length or tail moment, and – by introduction of clearly definable selection criteria based on image analysis algorithms – clearly improve objectivity and standardization of the analysis procedure.Results prove the high reproducibility, flexibility, efficiency and suitability of the procedure as a fully automated analysis method in higher throughput genotoxicity testing in vitro.  相似文献   
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Immunosuppression after kidney transplantation is a major cause of skin tumours. The carcinoma incidence 10 years after transplantation is 15% and after 20 years of immunosuppressive therapy is approximately 50%. Epidemiological screening programmes have documented ultraviolet exposure and human papillomavirus (HPV) as risk factors for the development of skin neoplasias in kidney transplant recipients. Because the course of HPV-associated lesions during immunosuppression is marked by a higher risk of metastasis, early diagnosis is important. Therefore, besides investigation in HPV typing, the use of additional cellular markers such as p16INK4a will improve recognition of neoplastic skin lesions. Moreover, screening programmes of HPV-induced lesions using cellular markers will help explore the mechanism of viral-induced skin tumour.  相似文献   
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BACKGROUND: Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism and chronic anovulation. The genetic background of the insulin resistance frequently associated with PCOS is unclear. OBJECTIVES: To examine the influe nce of the Pro12Ala polymorphism of the peroxisome proliferator activated receptor gamma (PPARgamma), which is thought to play a role in the regulation of insulin sensitivity, on endocrine and metabolic parameters in PCOS patients. METHODS: PPARgamma alleles were analysed in 102 PCOS patients (age 27 +/- 5.3 years) and 104 age matched control women. PCOS was defined by the NIH-criteria as the presence of chronic oligo- or anovulation and hyperandrogenism. Family history and clinical parameters were evaluated by personal interview and physical examination, parameters of insulin resistance [homeostasis model assessment (HOMA) and Matsuda-index] were evaluated with a glucose tolerance test. RESULTS: Seventy-nine (77.5%) PCOS patients were carriers of the wild-type PPARgamma allele (Pro/Pro), while 23 (22.5%) had at least one Ala allele (X/Ala), with an equal distribution in controls. X/Ala PCOS women were more insulin-sensitive, evidenced by lower fasting insulin, HOMA index and insulin secretion. Differences in insulin resistance did not depend on body mass index. The genotype had no influence on lipid status, leptin, adiponectin, ghrelin, or family history of type 2 diabetes. A significantly lower proportion of Pro/Ala patients had hirsutism and they had on average lower hirsutism scores than Pro/Pro patients. No relationship was found between the Pro/Ala polymorphism and other signs of hyperandrogenism. CONCLUSION: The Pro12Ala polymorphism of the PPARgamma gene is associated with increased insulin sensitivity and lower hirsutism scores in PCOS women.  相似文献   
90.
BACKGROUND: In patients with dilated cardiomyopathy (DCM) and severe congestive heart failure, immunoadsorption (IA) and subsequent IgG substitution leads to an acute and prolonged hemodynamic improvement. Goal of this study was to investigate the long-term effect of immunoadsorption on morbidity. METHODS: In a retrospective analysis of 34 patients (17 patients who have received immunoadsorption therapy and 17 control patients) were included. Inclusion criteria were DCM, left ventricular ejection fraction less than 35%, NYHA classes II-III. The average time after immunoadsorption was 3.0 years (median 2.3 years). Both groups did not differ concerning sex, age, duration of disease, medication, baseline ejection fraction and NYHA class. RESULTS: In patients who have received immunoadsorption (IA) the days of hospitalisation for congestive heart failure per year could be significantly reduced in contrast to the control patients (17.2 days prior to IA, 4.3 days after IA). Even if the procedural days for immunoadsorption were included there was still a significant reduction of hospitalisation if IA therapy was longer than 2.5 years ago. The days of hospitalisation increased gradually with time during the follow up period. IA induced an acute increase in EF (19.8-25.7%, p<0.01 vs. baseline). CONCLUSION: IA not only leads to an acute hemodynamic improvement in patients with DCM but may also reduce morbidity in these patients during the next 3 years.  相似文献   
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