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Five pancreatic carcinomas induced by N -nitrosobis(2-hydroxypropyl)amine in Syrian golden hamsters were analyzed for activation of Ki- ras at codons 12 and 13, using the polymerase chain reaction and direct sequencing. The Ki- ras gene was shown to be activated in four of the five carcinomas, and the results were further confirmed by subcloning and sequencing. All the mutations involved a G-to-A transition at the second position of codon 12, which resulted in a change at the amino acid level from glycine to aspartic acid. This mutation is identical with that reported for pancreatic tumors of Syrian hamsters induced by N -nitrosobis(2-oxopropyl)amine.  相似文献   
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This was a case–control study to analyze the associations between calcium urolithiasis and the urokinase polymorphisms, P141L (rs2227564) and 3′-UTR C>T (rs4065), in a Japanese population. Cases consisted of 232 patients with urinary calcium stones (174 men and 58 women) who presented to a general hospital between April 2009 and June 2011. Among these cases, 115 (49.6 %) patients had calcium oxalate stones alone, and 113 (48.7 %) patients had calcium oxalate stones mixed with calcium phosphate stones. Controls consisted of 454 subjects who had a routine health check-up in the same prefecture. The two polymorphisms were genotyped via polymerase chain reaction with confronting two-pair primers. In the control group, the genotype frequencies of P141L were 0.573 for PP, 0.375 for PL, and 0.052 for LL, and those of 3′-UTR C>T were 0.835 for CC, 0.165 for CT, and TT was not identified. Neither of the polymorphisms was significantly associated with urolithiasis. The age- and sex-adjusted odds ratios of urolithiasis were 0.96 [95 % confidence interval (CI), 0.66–1.41] for PL and 1.22 (0.58–2.57) for LL as compared with PP genotype of P141L, and 1.01 (0.62–1.64) for CT as compared with CC genotype of 3′-UTR C>T. When compared with the PP genotype of P141L, the frequency of PL was significantly lower in female cases with a family history of urolithiasis than in females without such family history (p = 0.028). P141L and 3′-UTR polymorphisms of the urokinase gene are not associated with urolithiasis in a Japanese population.  相似文献   
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BACKGROUND: The alpha-amylase isozymes can be detected separately by electrophoresis; however, sometimes the identification is difficult because of their microheterogeneity. In the present study, we tried to establish a convenient method for the detection of alpha-amylase isozyme expression. METHODS: The procedure is based on three different restriction sites presented in those genes; a PstI site in both AMY 2A and 2B genes, a HaeII site in both AMY 1 and 2A genes, and a BamHI site in AMY 2B gene. After amplification from total tissue RNAs by RT-PCR with primers that were able to cover each exon, the products were cleaved with corresponding restriction endonucleases. RESULTS: This method was applied to human samples from the parotid gland, liver (non-hepatoma), hepatoma and white blood cells (WBCs). The results indicated that the parotid gland and hepatoma (also liver) clearly expressed AMY 1 and AMY 2B genes, respectively. However, AMY 2B gene was also expressed apparently in WBCs, which produced salivary-type isozyme of the alpha-amylase, although the amylase protein was not able to identify for the hepatic isozyme. CONCLUSIONS: The method presented here might be convenient and useful for the determination of alpha-amylase isozyme expression in humans.  相似文献   
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OBJECTIVE: Aging and tumor-related malnutrition are associated with increased inflammatory cytokine levels. However, it is unclear whether this influences the outcomes of surgery. We explored the relationships between cytokines and surgical complications among patients undergoing surgery for colorectal cancer. DESIGN: Laboratory experiment. SETTING: Surgery department of school of medicine. PATIENTS: One hundred patients with colorectal cancer. INTERVENTIONS: The perioperative circulating levels of interleukin (IL)-1beta, IL-6, and IL-1 receptor antagonist (Ra) were determined, and the numbers of circulating lymphocytes and neutrophils were counted. MEASUREMENTS AND MAIN RESULTS: Trends toward increasing postoperative infection were observed among patients who were older and had lower body mass index. Preoperative IL-1Ra and intraoperative blood loss, however, remained the only two independent predictors of postoperative infection. Clinically, patients with low preoperative IL-1Ra most frequently were the elderly with low body mass index. Postoperatively, elderly patients with low body mass index showed an exaggerated IL-6 response, followed by an exaggerated postoperative inflammatory response and increased postoperative loss of body weight. In contrast, normal immunoreactivity was preserved in well-nourished elderly patients. CONCLUSIONS: In colorectal cancer patients undergoing surgery, low preoperative IL-1Ra is associated with postoperative infection. In our patient population, lower IL-1Ra level is commonly observed in the elderly with low body mass index. These findings suggest that postoperative infection, frequently seen in the nutritionally deficient elderly, may be the result of defective immunoinflammatory adaptation system.  相似文献   
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OBJECTIVE: Crescent formation in the renal glomerulus is a typical manifestation of progressive glomerulopathy associated with fatal renal failure; therefore, its prevention is of clinical importance. Little is known about the pathogenic mechanism for crescent formation. This study was undertaken in an attempt to identify the events that are critical for crescent formation in immune complex crescentic glomerulonephritis (CGN) by analyzing a novel mutant strain of mice. METHODS: A spontaneous mutant strain of mice was isolated from the autoimmune-prone strain EOD, which stably develops fatal CGN. The mutant phenotypes were assessed histopathologically, hematologically, and immunologically. The mutation was searched for with positional cloning using microsatellite markers. RESULTS: Compared with wild-type EOD (WT-EOD) mice, mutant EOD (mut-EOD) mice showed marked improvement in CGN in conjunction with an improvement in spontaneous mortality. In WT-EOD mice, an inverse correlation between blood urea nitrogen concentration and blood platelet count and massive accumulation of platelets in the glomerulus were evident, suggesting that an accumulation of platelets in the glomerulus contributes to the progression of CGN. The mutant platelets showed an abnormal aggregation in response to collagen and thrombin, associated with a bleeding tendency in mut-EOD mice. Genetic analysis revealed a deleterious mutation in the cappuccino gene (cno), which encodes a protein that belongs to a complex called the biogenesis of lysosome-related organelle complex 1 and is profoundly involved in platelet function. Morphologic examination revealed a partial defect in dense body formation in the delta-granule of platelets. CONCLUSION: The present findings suggest that platelet functions have a critical role in crescent formation in autoimmune GN.  相似文献   
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