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81.
PURPOSE: Beh?et's disease (BD) is known to be associated with HLA-B51 in many ethnic groups. However, the pathogenic gene responsible for BD is as yet unknown. To localize the critical region of the pathogenic gene, microsatellite markers distributed around the HLA-B gene were investigated. The BD patients studied were of three ethnic origins: Japanese, Greek, or Italian. METHODS: The total group consisted of 172 BD patients, of whom were 95 Japanese, 55 Greek, and 22 Italian. Eight polymorphic microsatellite markers distributed within 1100 kb of the HLA-B gene were analyzed using PCR and subsequent automated fragment detection by fluorescent-based technology. RESULTS: Among the eight markers, allele 348 of the MIB microsatellite was remarkably common in all three BD populations (Japanese, PC: = 0.000014; Greek, PC: = 0. 00047; Italian, PC: = 0.11). However, HLA-B51 was found to be the marker most strongly associated with BD in each population (Japanese, PC: = 0.000000000017; Greek, PC: = 0.00000032; Italian, PC: = 0. 0074). In genotypic differentiation between the patients and controls, only HLA-B51 was found to be significantly associated with BD in all three populations. Stratification analysis suggested that significant associations of BD with MICA and other microsatellites resulted from a linkage disequilibrium with HLA-B51. CONCLUSIONS: These results suggest that the pathogenic gene of BD is HLA-B51 itself and not other genes located in the vicinity of HLA-B.  相似文献   
82.
Histopathological diagnosis is the ultimate method of attaining the final diagnosis; however, the observation range is limited to the two‐dimensional plane, and it requires thin slicing of the tissue, which limits diagnostic information. To seek solutions for these problems, we proposed a novel imaging‐based histopathological examination. We used the multiphoton excitation microscopy (MPM) technique to establish a method for visualizing unfixed/unstained human breast tissues. Under near‐infrared ray excitation, fresh human breast tissues emitted fluorescent signals with three major peaks, which enabled visualizing the breast tissue morphology without any fixation or dye staining. Our study using human breast tissue samples from 32 patients indicated that experienced pathologists can estimate normal or cancerous lesions using only these MPM images with a kappa coefficient of 1.0. Moreover, we developed an image classification algorithm with artificial intelligence that enabled us to automatically define cancer cells in small areas with a high sensitivity of ≥0.942. Taken together, label‐free MPM imaging is a promising method for the real‐time automatic diagnosis of breast cancer.  相似文献   
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We investigated whether correlations between mRNA levels of cytokines versus other proteins from patchy lesion could estimate cytokine paracrine signaling in vivo. Experiments with rat experimental autoimmune myocarditis (EAM), a patchy myocarditis model, indicated IL-1 and other protein levels were correlated, indicating paracrine signaling pathways in vivo.  相似文献   
87.
Liver regeneration in a patient with fulminant hepatic failure (FHF) who underwent living-related partial liver transplantation (LRLT) was investigated regarding hepatic growth factors. The patient was a 16-yr-old Japanese male who developed severe subacute FHF. LRLT was performed using an extended left lobe of the ABO matched patient's mother. In the recipient, the pre-transplant levels of both plasma hepatocyte growth factor (HGF) and transforming growth factor (TGF)-beta were extremely high and rapidly decreased following the liver replacement. The liver volume evaluated using a CAT scan increased 195% after 2 wk in graft liver and 110% after 2 wk in the hepatectomized donor. The explanted liver (FHF liver), the liver from donor (normal liver), and the graft liver [the 3rd post-transplant day (POD 3)] were all investigated immunohistochemically. FHF liver: No liver regeneration was observed [proliferative cell nuclear antigen (PCNA) labeling index (L.I.): 0%]. In the liver, both HGF in the hepatocytes and c-met on the membrane of the hepatocytes were positive. TGF-beta was positive in the hepatocytes and no apoptosis was detected by the TUNEL method. Donor liver (POD 0): Few PCNA stained hepatocytes were detected. No HGF was detected but c-met was clearly detected on the cell membrane of the hepatocytes. Neither TGF-beta nor apoptosis was detected. Graft liver (POD 3): The PCNA L.I. was conspicuous at 40%. HGF was positive in non-parenchymal cells and c-met was positive in the cytoplasm of the hepatocytes. TGF-beta was negative while apoptosis was positive in the zone 3 hepatocytes. In conclusion, these findings suggested that the liver of the patient with FHF did not respond to liver regenerative stimulus, in part, through involvement of inhibitor TGF-beta. On POD 3, the transplanted graft was in a vigorous regenerative status in comparison to that in the hepatectomized donor. The HGF/c-met system is thought to be involved in the mechanism of regeneration. Intrahepatic apoptosis was detected in the graft on the 3rd post-transplant day probably due to transient ischemia in the liver, which was not related to the Fas/Fas-ligand system.  相似文献   
88.
OBJECTIVES: The purpose of this study was to determine the most suitable candidates for scalene lymph node biopsy to detect non-palpable scalene lymph node metastasis (N(3)-scalene) in non-small cell lung cancer patients. METHODS: Standard cervical mediastioscopies and ipsilateral scalene lymph node biopsies were performed preoperatively by a single surgeon on 121 consecutive patients with non-small cell lung cancer scheduled to have surgical resection between January 1997 and August 2002, who had neither evidence of distant metastasis on imaging diagnosis nor palpable supraclavicular lymph nodes. RESULTS: N(3)-scalene was detected in six patients (5.0%), who all had non-squamous cell carcinoma, including one (1.0%) out of 98 patients with negative standard cervical mediastinoscopy and five (21.7%) out of the remaining 23 patients with positive mediastinal lymph node involvement. There was a significant difference in the incidence of the N(3)-scalene between the two groups (P<0.01). Five patients with N(3)-scalene had metastatic lesions in the multilevel mediastinal lymph node station on the same side as the cancer (multilevel N(2)), and accounted for 31.3% of 16 patients with multilevel N(2) disease. The N(3)-scalene was detected in 5 (45.5%) of 11 patients with lung cancer classified as non-squamous cell carcinoma with multilevel N(2) disease. CONCLUSIONS: The results of the present study suggest that non-palpable scalene lymph node biopsy is indicated for lung cancer patients diagnosed as having non-squamous cell carcinoma with mediastinoscopic multilevel N(2) disease.  相似文献   
89.
Stroke leaves serious neurological sequelae, which require long-term medical and social care, imposing financial and mental burdens on the patients and their families, and causing enormous losses to society. It is currently required that medical resources be used efficiently and the cost-effectiveness of treatment be analyzed carefully. We conducted a follow-up survey of stroke patients admitted to the hospital attached to our university in order to build a picture of the current status of chronic-phase stroke medical treatment. In total, 330 patients were analyzed in this study. We evaluated utility and medical cost at one year after onset. To investigate the relationship between activities of daily living (ADL) classified according to the modified Rankin scale (mRS) and quality of life (QOL), utility was calculated for each ADL level. Utility at 1 year post-onset for each mRS level was: ADL0, 0.89; ADL1, 0.79; ADL2, 0.65; ADL3, 0.58; ADL4, 0.36; and ADL5, 0.09. A significant correlation was seen between utility and mRS. Direct monthly medical costs at 1 year post-onset were 61,536 yen in the ADL0 group and 383,444 yen in the ADL5 group, indicating that a worse ADL score required higher medical costs. Direct monthly costs were significantly different between ADL levels. This present study has clarified the QOL and medical costs of chronic-phase stroke patients, and many cost-utility analyses will be based on our data in the future in Japan.  相似文献   
90.
Objective: To report four cases of rice bodies (RBs) showing remarkable size variations and discuss their pathogenesis. Design and patients: Based on analysis of the clinical data, we speculate on the pathogenesis of RBs using immunohistochemical and ultrastructural methods. The patients comprised three men and one woman, three with RBs in the subacromial bursae and one in the wrist synovial sheath, aged 28 (woman), 44, 50 and 81 (wrist) years, respectively. Results: There were no particular differences in clinical data among the patients. T2-weighted MR imaging was very useful for diagnosis of the RBs, allowing their clear delineation from the bursal fluid. The RBs consisted of a layered protein- aceous substance with vague targetoid cut surfaces. Much fibrin and a lesser amount of collagen fibers were recognized together with various mononuclear cells, which were few in number and predominantly T cells. The bursae and synovial sheath had multiple fibrinoid spheroids at the luminal surface. Conclusion: Fibrinoid nodular deposits probably became detached, forming the nuclei of RBs and growing to a giant RB 65 mm in diameter. Received: 27 September 1999 Revision requested: 5 January 2000, 21 March 2000 Revision received: 21 March 2000, 14 April 2000 Accepted: 8 June 2000  相似文献   
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