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101.
A 74-year-old Japanese woman diagnosed with autosomal dominant polycystic kidney disease (ADPKD) was admitted to our institute for the further examination of right-side groin pain developing in the past week. The patient was diagnosed with polymyositis (PM). Diagnostic imaging showed a mass lesion measuring 8 cm and a renal stone in the right kidney. Immediately following surgical resection of the right kidney, the patient''s serum CK decreased to the normal range. A histopathological analysis showed well-differentiated squamous cell carcinoma. In conclusion, this case showed a close relationship between the occurrence of squamous cell carcinoma and the development of PM in an ADPKD patient.  相似文献   
102.
BACKGROUND: To investigate the activation patterns and conduction velocity (CV) in the posterolateral right atrial (RA) wall during typical counterclockwise atrial flutter (AFL) using an electroanatomic mapping system. METHODS AND RESULTS: During typical AFL in 25 patients, the transverse conduction pattern and CV were classified and calculated. The line blocking transverse conduction was defined by the conduction pattern and double potentials recorded during mapping. There were 3 types (including 2 subtypes) of transverse conduction pattern based on the conduction blocks across the posterolateral RA in a line between the superior and inferior venae cava. Trans-cristal conduction activation in a horizontal direction was seen in all but 4 patients. The CV in the gap area was 0.59+/-0.21 m/s. CONCLUSIONS: Three types of transverse conduction pattern were observed during trans-ctristal conduction and the trans-ctristal CV was relatively slower than that in other parts of the RA, except for the isthmus.  相似文献   
103.
Ethanol exerts damaging effects on gastric mucosa and delays ulcer healing. To investigate the effect of ethanol on the wound repairing process, we used a wound repair model using primary cultured gastric mucosal cells. A confluent monolayer gastric mucosal cell sheet consisting mainly of mucous cells was wounded to make a cell-free area of constant size. Cell-free area was restored with time after wounding and monitored every 12 hr using a computer image analyzer to observe epithelial cell restoration quantitatively in the presence and absence of ethanol (2.0%). It was found that, although the control wound was completely repaired in 36 to 48 hr, the group treated with 2.0% ethanol showed a significant delay of repair. In the control, 5-bromodeoxyuridine-positive cells appeared around the wound in 24 to 36 hr. In contrast, the group treated with 2.0% ethanol showed no 5-bromodeoxyuridine-positive cells during the experiment. In conclusion, 2.0% ethanol retarded the repair of gastric mucosal restoration by inhibiting the initial gastric cell migration, followed by inhibition of proliferation of cells.  相似文献   
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Inflammatory bowel diseases such as ulcerative colitis or Crohn's disease frequently cause epithelial damage in the intestine. In general, the intestinal epithelium is able to rapidly repair itself by the restitution, proliferation, and differentiation of epithelial cells when such tissue damage occurs. However, severe and continuous inflammation could disturb the intrinsic repair system, resulting in refractory ulcers in the intestine. In this review, we will describe the recent findings of the cellular and molecular mechanisms regulating the regeneration process of the intestinal epithelium. Furthermore, we will propose bone marrow cells as a novel source of cells to regenerate the damaged intestinal epithelium. Bone marrow cells are the only cells of extra-gastrointestinal origin that are shown to contribute to the regeneration of the intestinal epithelium. Further studies of these cells and molecules may lead to a novel therapy for the repair of damaged intestinal epithelium.  相似文献   
107.
 Hepatocyte growth factor (HGF) is a unique growth factor with many protective functions. Previously, we demonstrated that HGF stimulated growth of endothelial cells without replication of vascular smooth muscle cells (VSMC) and that angiotensin (Ang) II significantly decreased local HGF production in VSMC. Moreover, we also reported that high glucose significantly decreased local vascular HGF production. Therefore, we examined effects of Ang II blockade on vascular HGF expression and endothelial injury in diabetic hypertensive rats. An angiotensin-converting enzyme inhibitor (quinapril) and an Ang II type 1 receptor antagonist (GA-0113) or vehicle was administrated to diabetic spontaneously hypertensive rats (SHR-DM), in whom diabetes was induced by streptozotocin. Endothelial function was evaluated by the vasodilator response to acetylcholine, and the expression of vascular HGF and its receptor, c-met, was examined by immunohistochemistry. Both quinapril and GA-0113 significantly improved the vasodilator response to acetylcholine (P < 0.01), while vehicle did not as compared to untreated normotensive Wistar-Kyoto rats (WKY). We next examined the effects of Ang II blockade on vascular HGF expression in SHR-DM. Importantly, the vascular HGF level was markedly decreased in SHR-DM as compared to WKY, while Ang II blockade by quinapril or GA-0113 significantly increased positive staining for HGF in SHR-DM. Similarly, staining of its specific receptor, c-met, was less in the blood vessels of SHR-DM as compared to WKY. In contrast, Ang II blockade also significantly increased c-met production in SHR-DM. The present data demonstrated the improvement of endothelial dysfunction by Ang II blockade in SHR-SM, accompanied by an increase in vascular HGF and c-met. Received: June 7, 2002 / Accepted: September 21, 2002 Acknowledgments We wish to thank Rie Kosai and Keiko Yamaguchi for their excellent technical assistance. This work was partially supported by grants from the Japan Health Sciences Foundation, a Grant-in-Aid from The Ministry of Public Health and Welfare, a Grant-in-Aid for the Development of Innovative Technology, a Grant-in-Aid from Japan Promotion of Science, and through Special Coordination Funds of the Ministry of Education, Culture, Sports, Science and Technology, the Japanese Government. Correspondence to N. Tomita  相似文献   
108.
BACKGROUND: Ulcerative colitis (UC) is a chronic inflammatory bowel disease associated with recurring inflammation of the colorectal mucosa. Recently, cytapheresis has emerged as a new treatment for patients with UC. Removal methods are mainly performed with beads [granulocyte and monocyte/macrophage adsorptive apheresis (GMCAP)] or filters [leukocytapheresis (LCAP)]. Both treatments have been reported to be effective for active UC. There have been few trials, however, comparing the efficacy of GMCAP and LCAP. In this study, we prospectively evaluated the efficacy of LCAP and GMCAP for the treatment of active UC. METHODS: Thirty-nine patients [18 male, 21 female; mean age 38.7 years; duration of disease 6 years; clinical activity index (CAI) >6 points] with moderate-to-severe active UC were randomly assigned to the LCAP (n=21) or GMCAP group (n=17). Adacolumn (cellulose acetate beads; Japan Immunoresearch Laboratories, Takasaki, Japan) for GMCAP and Cellsorba EX (polyethylene phthalate fibers; Asahi Medical Co. Ltd, Tokyo, Japan) for LCAP were used for leukocyte removal. Patients received two sessions of cytapheresis in the first week, followed by four weekly administrations. Steroid doses were tapered if patients achieved clinical improvement. When the CAI score had decreased by 5 points or more, the patient was considered to have improved. RESULTS: Thirteen patients in the GMCAP group and 14 in the LCAP group achieved clinical improvement. No significant difference was found in clinical response and clinical course between LCAP and GMCAP. Hemoglobin levels were significantly decreased immediately after one session of cytapheresis in the LCAP group. No severe adverse effects were observed in any of the patients. No significant differences were observed in any clinical parameters predictive of a response to either LCAP or GMCAP. But in all patients receiving cytapheresis, a high CAI score was a significant risk factor for treatment failure. All of the cytapheresis nonresponders had CAI scores >or=16. CONCLUSION: Both GMCAP and LCAP were effective treatments for active UC. Patients with severe UC and a high CAI score were, however, refractory to treatment.  相似文献   
109.
Reactive oxygen species are considered to play a role in the development of diabetes mellitus and its complications. Human MTH1 (mutT homologue 1) has 8-oxo-7,8-dihydrodeoxyguanosine triphosphatase activity, which repairs oxidized forms of dGTP. This enzyme is known to have a thermolabile Met83 variant. We examined whether Val83Met polymorphism of human MTH1 gene is associated with type 1 diabetes mellitus. We recruited 156 type 1 diabetic patients (59 males and 97 females). The polymorphism was analyzed by restriction fragment length polymorphism analysis with Nsi I. The Met/Met genotype at codon 83 was very rare in both control and patient groups. Val/Met genotype tended to be more frequent in the whole type 1 diabetic patients than in controls. When subjects were divided into subgroups according to gender, there were no differences in the genotype and allele frequencies between patients and controls in males. On the other hand, in female type 1 diabetic patients, the Val/Met genotype was more frequent than in female controls (corrected P = 0.102). The Met allele was significantly more frequent in female type 1 diabetic patients than in female controls (corrected P = 0.022). Our results suggested that the Met allele at codon 83 of MTH1 gene might be involved in the development of type 1 diabetes mellitus in the Japanese female population.  相似文献   
110.
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