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21.
22.
Analysis of K-<Emphasis Type="Italic">ras</Emphasis> Codon 12 Mutation in Flat and Nodular Variants of Serrated Adenoma in the Colon 总被引:4,自引:0,他引:4
Higashidani Y Tamura S Morita T Tadokoro T Yokoyama Y Miyazaki J Yang Y Takeuchi S Taguchi H Onishi S 《Diseases of the colon and rectum》2003,46(3):327-332
PURPOSE: The developmental process of serrated adenomas is obscure, and the importance of genetic alterations has not been elucidated clearly. The possibility that the developmental process and genetic alterations of serrated adenomas could differ from those of ordinary tubular adenomas was explored in this work.
METHODS: Serrated adenomas were obtained by endoscopic resection (n = 57) and divided into two groups: flat (n = 10) and nodular (n = 47). Mutation of the K-ras gene was analyzed by enriched polymerase chain reaction–enzyme-linked mini-sequence assay, which can detect not only the presence of a mutation but also the mutation type of K-ras codon 12 with high sensitivity. Methylation-specific polymerase chain reaction was performed with specific primers for the DNA repair gene O6-methylguanine-DNA methyltransferase.
RESULTS: Serrated adenomas located in the rectum were more likely to have a K-ras mutation (9/12, 75 percent), whereas serrated adenomas of the flat type were less likely to have one (1/10, 10 percent). Furthermore, nodular serrated adenomas that occurred in the rectum possessed a high frequency of K-ras gene codon 12 point mutation (8/10, 80 percent) despite an overall frequency of 46.8 percent (22/47). A mutation of the K-ras codon 12 gene was detected in 23 (40.4 percent) of 57 serrated adenomas. Three types of point mutations of codon 12 were detected, with the mutation of GAT being observed most frequently.
CONCLUSIONS: This study shows that development of nodular serrated adenomas may depend on the mutation of the K-ras codon 12 gene, whereas development of flat serrated adenomas may not. Additionally, serrated adenomas that occur in the rectum are closely related to the mutation of the K-ras codon 12 gene. K-ras mutations in serrated adenomas may be unaffected by the epigenetic silencing of O6-methylguanine-DNA methyltransferase by promoter hypermethylation. 相似文献
23.
Kose Segawa M.D. Saburo Nakazawa M.D. Yoshihisa Tsukamoto M.D. Hidemi Goto M.D. Kenji Yamao M.D. Satoshi Hase M.D. Toshimasa Osada M.D. Tomiyasu Arisawa M.D. 《The American journal of gastroenterology》1988,83(4):373-379
We performed morphological and physiological studies in 43 male patients with alcohol dependence (ALC) who had no other apparent lesions in the upper gastrointestinal tract except atrophic and erosive gastritis. A gastric secretory study in which tetragastrin was used as the stimulant revealed that acid and pepsin secretion was less in ALC patients than in hospital controls (p less than 0.001). Endoscopic biopsy specimens of gastric mucosa from ALC patients revealed that atrophy of the gastric mucosa advanced with age. A strong negative correlation was also found between the secretory capacity of the stomach and the degree of atrophy. Possibly, the interval between recurrent episodes of acute mucosal damage was too short to allow complete healing of mucosal lesions. Failure to regenerate denuded epithelium would result in a decrease in the gastric secretory area. Thus, chronic alcohol abuse seems to be an etiological factor in atrophic gastritis. 相似文献
24.
25.
Fukuda S Itamoto T Nakahara H Kohashi T Ohdan H Hino H Ochi M Tashiro H Asahara T 《Hepato-gastroenterology》2005,52(64):1163-1167
BACKGROUND/AIMS: Solitary small-sized HCCs tend to be considered as less aggressive cancer, and non-surgical treatments have recently been preferred. The aim of this study was to clarify the clinicopathological features and the prognostic factors of small-sized HCCs and to evaluate the significance of hepatic resection for them. METHODOLOGY: Eighty patients with HCC up to 2cm in diameter who had undergone hepatic resection were enrolled in this study. We investigated the clinicopathological features and evaluated the prognostic factors by univariate and multivariate analyses. RESULTS: The overall survival rates at 3, 5 and 10 years were 83%, 69% and 36%, respectively, and the corresponding disease-free survival rates were 63%, 41% and 10%. Well-differentiated, moderately differentiated and poorly differentiated HCC were detected in 29%, 65% and 6% of the patients, respectively. Furthermore, microscopic portal vein invasion (vp), hepatic vein invasion (vv) and intrahepatic metastasis (im) were positive in 15%, 4% and 10% of the patients, respectively. Multivariate analysis revealed that Child-Pugh classification (p=0.005) and vp (p=0.0008) were independent prognostic factors for survival rate and that platelet count (p=0.002) and tumor differentiation (p=0.0016) were independent prognostic factors for disease-free survival rate. CONCLUSIONS: Even solitary small-sized (up to 2cm in diameter) HCC already have the characteristics of advanced HCC. When hepatic function is well preserved, hepatic resection should be the first choice for local control, especially in cases of moderately to poorly differentiated HCC, because the frequency of microscopic vascular invasion is high. 相似文献
26.
Yukihiro Tsuchiya Fumitake Ishihara Goro Kajiyama Saburo Nakazawa Masao Otho Hiroshi Tanimura Yoshikazu Akura Minoru Harada Masabumi Hihara Yukio Kawai Yukihiro Kono Hajime Koshiyama Masahiro Morita Michiko Nakajima Kyoichiro Nishina Hiroshi Sagawa Terufumi Sakai Mitsuo Shoji Kayoko Sone Yoshihiro Sugimoto Keiichi Sugiyama Osamu Takahara Tomoo Takamura Susumu Tazuma Hideki Wakamatsu 《Journal of gastroenterology》1995,30(6):768-774
The use of bile acid dissolution therapy in extracorporeal shockwave lithotripsy of gallstones, remains controversial. Our
study examined whether chemolitholysis after sufficient disintegration enhanced stone clearance within 6 months of the first
lithotripsy. A total of 143 patients who developed one to three radiolucent stones measuring⪯30 mm in diameter were randomly
separated into two treatment groups: 47% were given lithotripsy alone, and 53% lithotripsy plus ursodeoxycholic acid (UDCA).
Repeated piezoelectric lithotripsy was given, with no limit on the total number of treatment sessions, to pulverize or disintegrate
stones into fragments<3 mm. Stones were disintegrated in 97% of all patients, and the fragments were ⪯2 mm in 50% of these
patients. According to an intention-to-treat analysis, 52% in the lithotripsy alone group and 58% in the UDCA group were free
of stones 6 months after the first lithotripsy (P=0.61). Of the patients with fragments⪯2 mm, 71% in the former and 86% in the latter group were free of stones 6 months after
the first lithotripsy, with no significant difference between the groups. Biliary pain occurred in 25% of all patients, including
3 with acute cholecystitis. We concluded that the sufficient disintegration of gallstones achieved with repeated lithotripsy
enhanced the early clearance of fragments, regardless of whether chemolitholysis was employed. 相似文献
27.
Telomerase activity and telomere length of peripheral blood mononuclear cells in SLE patients 总被引:4,自引:0,他引:4
Kurosaka D Yasuda J Yoshida K Yokoyama T Ozawa Y Obayashi Y Kingetsu I Saito S Yamada A 《Lupus》2003,12(8):591-599
We evaluated the clinical significance of the telomerase activity and telomere length of peripheral blood mononuclear cells (PBMC) in systemic lupus erythematosus (SLE). PBMC were isolated from 55 patients with SLE and the telomerase activity was measured by TRAP assay. The telomere length of PBMC was also measured in 30 of these subjects. As a control group, 45 healthy adults with no particular clinical history were studied. The results were compared with clinical data. In patients with active SLE, the telomerase activity of PBMC was significantly increased compared with the control group. In patients with inactive SLE, the PBMC telomerase activity was not different compared with the controls in their 20s, 30s and 40s, but it was significantly increased compared with the controls in their 50s. In SLE patients, the telomerase activity of PBMC was significantly correlated with modified SLEDAI. The telomere length of PBMC in younger SLE patients tended to be shorter than that in the controls, but no difference was observed in older patients. The correlation coefficient between the telomerase activity and telomere length of PBMC in SLE patients was not significant. Abnormalities in the telomerase activity and telomere length observed in SLE patients are considered to be important findings for evaluation of the pathology of SLE. 相似文献
28.
Saburo Onishi M.D. Toshiji Saibara Takashi Maeda Yasutake Yamamoto Kenichi Ito 《Journal of gastroenterology》1989,24(3):284-289
Serum inhibition of complement-derived leukocyte chemotaxis was examined in alcoholic liver disease with or without cirrhosis.
Chemotactic inhibitory activity (CIA) was detected with higher frequency and degree in alcoholic liver disease, especially
with liver cirrhosis compared with normal subjects and non-alcoholic liver cirrhosis. CIA was found in anti-IgA adsorbed fractions
in the sera of patients with alcoholic liver cirrhosis. Serum concentrations of IgAl and IgA2 in alcoholic liver disease were
statistically higher than in non-alcoholic liver cirrhosis. However, no correlation between CIA and the concentrations of
IgA subclasses was demonstrated in alcoholic liver disease. This serum inhibitor may partly explain the high susceptibility
to bacterial infection in alcoholic liver disease. 相似文献
29.
Dan H Tani K Hase K Shimizu T Tamiya H Biraa Y Huang L Yanagawa H Sone S 《Rheumatology international》2003,23(6):271-276
To determine the significance of CD13/aminopeptidase N in collagen vascular diseases (CVD), we examined its activity and expression in sera and disease sites of patients with CVD. Significantly higher aminopeptidase activity was detected in bronchoalveolar lavage fluid from patients with interstitial lung diseases due to rheumatoid arthritis (RA), polymyositis/dermatomyositis (PM/DM), systemic sclerosis (SSc), and Sjögren's syndrome than from control subjects. Increased aminopeptidase activity and increased expression of CD13/aminopeptidase N protein were found in alveolar macrophages from CVD patients with interstitial lung diseases. Significantly higher aminopeptidase activity was detected in pleural effusions from patients with systemic lupus erythematosus (SLE) than in transudate effusions. The mean aminopeptidase activity in synovial fluids from RA patients was significantly higher than from patients with osteoarthritis. The mean value of serum aminopeptidase activity was significantly higher in patients with SLE, RA, SSc, and PM/DM than in normal subjects. This study suggests that the activity of CD13/aminopeptidase N, locally produced in the disease site, is a useful marker for CVD and that CD13/aminopeptidase N may have an important role in the pathogenesis of CVD. 相似文献
30.
Sasaki H Kanai S Oyama T Miyashita Y Shirai K 《Journal of atherosclerosis and thrombosis》2005,12(4):218-224
This study was conducted to clarify the characteristics of colestimide responders. Forty-seven non-diabetic patients with high levels of low-density lipoprotein cholesterol (LDL-C) received colestimide at 3,000 mg/day and were followed up for 4 months. After 4 months, body weight was reduced but the change was not statistically significant. Total serum cholesterol (TC) and LDL-C levels significantly decreased from 280 to 232 mg/dl and from 195 to 150 mg/dl, respectively (p<0.01 versus before colestimide was administered). Serum triglyceride (TG) levels increased, but the change was not significant. Preheparin lipoprotein lipase mass (preheparin LPL mass) at baseline was significantly higher in colestimide responders (greater than a 20% decrease of LDL-C: n=28) than non-responders (76.2 ng/ml versus 50.3 ng/ml, p<0.05: n=19). Next, the subjects were divided into those with a high (n=33) and low (n=14) preheparin LPL mass at baseline. LDL-C levels were significantly decreased in patients with a high preheparin LPL mass while TG levels were significantly increased in patients with a low preheparin LPL mass. These results suggest that baseline preheparin LPL mass may be a marker of the response to colestimide. 相似文献