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111.
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An Analysis of the Development of Colonic Diverticulosis in the Japanese   总被引:2,自引:0,他引:2  
PURPOSE There are quite different characteristics between colonic diverticulosis in the West and that in Asia, including Japan. These differences include the predominance of a few diverticula over others, right-sidedness, young generation, male, and few complications. In Japan, colonic diverticulosis started increasing in the 1970s. This study was performed to obtain exact evidence of diverticular development in contemporary Japanese by observing changes in diverticula in the same individuals examined over a period of ten or more years. METHODS This study included 82 subjects (56 (68 percent) males and 26 (32 percent) females) who underwent barium enema examinations repeatedly for more than ten years from 1982 to 2000. The diverticula were categorized according to their location in the colon: right, left, or bilateral. They were also categorized by whether they appeared individually, were scattered with two to nine diverticula, or were numerous with ten or more diverticula. RESULTS At the beginning of observation, the most frequent location was the right side (55; 67 percent), followed by bilateral (20; 24 percent) and the left side (7; 9 percent). Ten or more years later, the number on the right side had decreased to 39 (48 percent). The number of bilateral diverticula had increased to 38 (46 percent), and the number on the left had barely changed, to 5 (6 percent). The number of diverticula increased from 253 to 604 (239 percent) in the right and from 380 to 929 (244 percent) in the bilateral. The initially very small number in the left increased from 9 to 48 (533 percent). The data show marked increases in the right and bilateral diverticula, and also the spread from the right side to the left side. CONCLUSION In contemporary Japanese, although the right predominated initially, diverticulosis showed a strong tendency to increase and spread from the right to the bilateral. The number of bilateral diverticula also tended to increase. The left did not change much. Presented at the meeting of The Japan Society of Coloproctological Dysfunction, Tokyo, Japan, September 1, 2001.  相似文献   
113.
Unmyelinated fiber sensory neuropathy differs in type 1 and type 2 diabetes   总被引:2,自引:0,他引:2  
BACKGROUND: Neuropathic pain is common in diabetic patients. Degeneration of sensory C-fibers in peripheral nerve plays a prominent role in the generation of neuropathic pain. We examined degenerative changes of C-fibers in two rat models with type 1 and type 2 diabetes. METHODS: Type 1 insulinopenic BB/Wor and type 2 hyperinsulinemic diabetic BBZDR/Wor-rats of 8 months duration with equal exposure to hyperglycemia were examined. Thermal hyperalgesia was monitored using an infrared thermal probe. C-fiber size, number, frequencies of denervated Schwann cells, regenerating C-fibers, type 2 axon/Schwann cell relationship and collagen pockets in the sural nerve were examined morphometrically. Neurotrophic receptor expression was examined by Western blotting. Neurotrophins and neuropeptides were examined by ELISA. RESULTS: Type 1 rats showed increased thermal hyperalgesia followed by a decrease. Hyperalgesia in type 2 rats showed a slower progression. These findings were associated with a 50% (p < 0.001) loss of C-fibers, increased frequencies of denervated Schwann cells (p < 0.001), regenerating fibers (p < 0.001), collagen pockets (p < 0.001) and type 2 axon/Schwann cell relationship (p < 0.001) in type 1, but not in type 2 rats. Expression of insulin receptor, IGF-1R, TrkA and C was decreased in BB/Wor rats, whereas BBZDR/Wor rats showed milder or no deficits. NGF and NT-3 in sciatic nerve and substance P and calcitonin gene-related peptide in dorsal root ganglia were decreased in type 1, but not in type 2 rats. CONCLUSION: The more severe molecular, functional and morphometric abnormalities of nociceptive C-fibers in type 1 insulinopenic rats compared to type 2 hyperinsulinemic rats suggest that impaired insulin action may play a more important pathogenetic role than hyperglycemia per se.  相似文献   
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The effect of spironolactone (SPIR) on lipopolysaccharide (LPS)-induced production of proinflammatory mediators was examined using RAW 264.7 macrophage-like cells and mouse peritoneal macrophages. SPIR significantly inhibited LPS-induced production of nitric oxide (NO), tumor necrosis factor-α and prostaglandin E2. The inhibition was not mediated by cell death. SPIR reduced the expression of an inducible NO synthase mRNA in response to LPS. SPIR significantly inhibited phosphorylation of p65 nuclear factor (NF)-κB in response to LPS. Furthermore, SPIR inhibited phosphorylation of IκB kinase (IKK) as an upstream molecule of NF-κB in response to LPS. LPS did not induce the production of aldosterone in RAW 264.7 cells. Taken together, SPIR is suggested to inhibit LPS-induced proinflammatory mediators via inactivation of IKK/NF-κB in LPS signaling.  相似文献   
117.
The interleukin-1 receptor antagonist (IL-1Ra) binds to IL-1 receptors and inhibits IL-1 activity. However, it is not clear whether IL-1Ra plays a protective role in periodontal disease. This study was undertaken to compare experimental periodontitis induced by Aggregatibacter actinomycetemcomitans in IL-1Ra knockout (KO) mice and wild-type (WT) mice. Computed tomography (CT) analysis and hematoxylin-and-eosin (H&E) and tartrate-resistant acid phosphatase (TRAP) staining were performed. In addition, osteoblasts were isolated; the mRNA expression of relevant genes was assessed by real-time quantitative PCR (qPCR); and calcification was detected by Alizarin Red staining. Infected IL-1Ra KO mice exhibited elevated (P, <0.05) levels of antibody against A. actinomycetemcomitans, bone loss in furcation areas, and alveolar fenestrations. Moreover, protein for tumor necrosis factor alpha (TNF-α) and IL-6, mRNA for macrophage colony-stimulating factor (M-CSF), and receptor activator of NF-κB ligand (RANKL) in IL-1Ra KO mouse osteoblasts stimulated with A. actinomycetemcomitans were increased (P, <0.05) compared to in WT mice. Alkaline phosphatase (ALP), bone sialoprotein (BSP), osteocalcin (OCN)/bone gla protein (BGP), and runt-related gene 2 (Runx2) mRNA levels were decreased (P, <0.05). IL-1α mRNA expression was increased, and calcification was not observed, in IL-1 Ra KO mouse osteoblasts. In brief, IL-1Ra deficiency promoted the expression of inflammatory cytokines beyond IL-1 and altered the expression of genes involved in bone resorption in A. actinomycetemcomitans-infected osteoblasts. Alterations consistent with rapid bone loss in infected IL-Ra KO mice were also observed for genes expressed in bone formation and calcification. In short, these data suggest that IL-1Ra may serve as a potential therapeutic drug for periodontal disease.  相似文献   
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This study aimed to kinetically analyze the nonlinear absorption and systemic exposure of telmisartan (TEL) after oral administration to rats by using a stable isotope-IV method. Rats were orally administered different dose of TEL, followed by the intravenous injection of 0.005 mg/kg of deuterium-labeled TEL (TEL-d3). Assuming that TEL-d3 shows same pharmacokinetic properties with TEL, systemic clearance (CLtot), oral bioavailability (Foral), and intestinal and hepatic availability (Fa*Fg, Fh) of TEL were calculated in each individual rat. AUCpo of TEL increased disproportionately with dose and showed a sigmoid-type relation, indicating the involvement of multi-nonlinear processes in oral absorption of TEL. Fa*Fg of TEL increased with dose at the low-dose range while decreased at the high-dose range. In contrast, Fh increased and CLtot decreased significantly in the middle range (2 to 6 mg/kg). As main factors of nonlinearity, saturations of solubility, efflux transport in the intestine, and the hepatic uptake of TEL were indicated. In conclusion, this study demonstrated a high possibility of a stable isotope-IV method to characterize complicated pharmacokinetic properties of oral drugs in animals, which can help to consider the future risks in their clinical use.  相似文献   
120.
Background/Aims: Endoscopic definitions and management of Barrett's esophagus vary widely among countries. To examine the current situation regarding diagnosis, epidemiology, management and treatment of Barrett's esophagus in East Asian countries using a questionnaire-based survey. Methods: Representative members of the Committee of the International Gastrointestinal Consensus Symposium developed and sent a questionnaire to major institutions in China, South Korea, Japan, Thailand, Indonesia, and the Philippines. Results: A total of 56 institutions in the 6 countries participated in the survey. We found that the presence of specialized columnar metaplasia is considered to be important for diagnosing Barrett's esophagus in East Asian countries except for Japan. C&M criteria have not been well accepted in East Asia. The palisade vessels are mainly used as a landmark for the esophagogastric junction in Japan. The prevalence of long segment Barrett's esophagus is extremely low in East Asia, while the prevalence of short segment Barrett's esophagus is very high only in Japan, likely due to different diagnostic criteria. Conclusion: Among East Asian countries, we found both similarities and differences regarding diagnosis and management of Barrett's esophagus. The findings in the present survey are helpful to understand the current situation of Barrett's esophagus in East Asian countries.  相似文献   
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