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OBJECTIVE: Interleukin-6 (IL-6) is a pleiotropic cytokine that regulates the immune response, inflammation, and hematopoiesis. Overproduction of IL-6 plays pathologic roles in rheumatoid arthritis (RA), and the blockade of IL-6 may be therapeutically effective for the disease. This study was undertaken to evaluate the safety and efficacy of a humanized anti-IL-6 receptor antibody, MRA, in patients with RA. METHODS: In a multicenter, double-blind, placebo-controlled trial, 164 patients with refractory RA were randomized to receive either MRA (4 mg/kg body weight or 8 mg/kg body weight) or placebo. MRA was administered intravenously every 4 weeks for a total of 3 months. The clinical responses were measured using the American College of Rheumatology (ACR) criteria. RESULTS: Treatment with MRA reduced disease activity in a dose-dependent manner. At 3 months, 78% of patients in the 8-mg group, 57% in the 4-mg group, and 11% in the placebo group achieved at least a 20% improvement in disease activity according to the ACR criteria (an ACR20 response) (P < 0.001 for 8-mg group versus placebo). Forty percent of patients in the 8-mg group and 1.9% in the placebo group achieved an ACR50 response (P < 0.001). The overall incidences of adverse events were 56%, 59%, and 51% in the placebo, 4-mg, and 8-mg groups, respectively, and the adverse events were not dose dependent. A blood cholesterol increase was observed in 44.0% of the patients. Liver function disorders and decreases in white blood cell counts were also observed, but these were mild and transient. There was no increase in antinuclear antibodies or anti-DNA antibodies. Anti-MRA antibodies were detected in 2 patients. CONCLUSION: Treatment with MRA was generally well tolerated and significantly reduced the disease activity of RA.  相似文献   
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Summary We screened 214 Japanese NIDDM (non-insulin-dependent) diabetic patients with a family history of diabetes for mutations in the mitochondrial tRNALeu(UUR) gene using polymerase chain reaction-restriction fragment length polymorphism and direct sequencing. Six patients were identified as having an A to G transition at position 3243 (3243 mutation), but no patients were detected with a T to C transition at position 3271, in the mitochondrial tRNALeu(UUR) gene. These two mutations were not present in 85 healthy control subjects. It was disclosed that the patients' mothers were also affected by diabetes mellitus in five of the six cases. In these six affected patients, the 3243 mutation shows variable phenotypes, such as the degree of multiple organ involvement, intrafamilial and interfamilial differences in disease characteristics, and the degree of the involvement of MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes) phenotype. Endocrinological examinations revealed that those diabetic patients with the 3243 mutation show not only beta-cell dysfunction, but also a defect in alpha-cell function, which is considered characteristic of diabetes with the 3243 mutation. When compared with 50 selected diabetic control subjects without the 3243 mutation, whose mothers, but not fathers, were found to have diabetes, it was established statistically that those with the 3243 mutation possess the following clinical characteristics; 1) the age of diabetes onset is lower, 2) they have lean body constitutions, and 3) they are more likely to be treated with insulin than control subjects. We suggest that diabetes with the 3243 mutation possesses phenotypes distinct from those in common forms of diabetes.Abbreviations NIDDM non-insulin-dependent diabetes mellitus - IDDM insulin-dependent diabetes mellitus - MELAS mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes - PCR polymerase chain reaction - RFLP restriction fragment length polymorphism - BMI body mass index - ICA islet cell antibody - ICSA islet cell surface antibody - GAD glutamic acid decarboxylase  相似文献   
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Expression of p53 and c-myc was investigated and compared with cell proliferative activity in a series of 40 hepatocellular carcinomas (HCC), by means of enhanced immunohistochemistry. p53 expression was demonstrated in 5 out of 40 HCC (12.5%) with the incidence increasing in proportion to the histological grading of malignancy: thus, 0% of well-differentiated, 6.9% of moderately differentiated and 33.3% of poorly differentiated lesions were positive. The proliferating-cell nuclear antigen (PCNA) labeling index also showed a statistically significant increase with this grading. Distribution patterns of PCNA-positive cell were divided into four types: scatter, marginal, mosaic and diffuse. Four HCC cases, predominantly of the poorly differentiated type, exhibited the diffuse pattern. Generally, p53 overexpression corresponded well with PCNA positivity. In contrast, there was no correlation between c-myc overexpression, found in 19 out of 40 HCC (47.5%), and histological grading of HCC or PCNA labeling index. The distribution pattern of c-myc-positive HCC cells was also different from that of PCNA and p53. Our results suggest that p53 overexpression closely relates to proliferation of HCC cells. Furthermore, there may be a consistent difference in regulatory mechanisms between p53 and c-myc expression in multistep hepatocarcinogenesis.  相似文献   
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Decrease in BSF-2/IL-6 response in advanced cases of multiple myeloma   总被引:2,自引:0,他引:2  
Human myeloma cells freshly isolated from 40 patients with IgG multiple myeloma (MM, 10 in stage I and 30 in stage III), were cultured for 48 hours with recombinant B cell stimulatory factor 2 (rBSF-2)/interleukin- 6 (IL-6), which is considered a major growth factor for myeloma cells. Uptake of 3H-thymidine by these purified myeloma cells was measured, and BSF-2 response was evaluated by stimulation index and delta cpm induced by rBSF-2. Myeloma cells from cases in stage I responded to rBSF-2 better than those in stage III. Moreover rBSF-2 responders also showed better response to chemotherapy. Therefore, these results suggest that in vitro response of myeloma cells to BSF-2 correlates with disease progression and clinical response in patients of MM.  相似文献   
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PurposeThis study compared the clinical success rates of mandibular fracture treatment using reconstruction plates or miniplates and clarified the selection criteria for reconstruction plates.MethodsAll patients who had surgically-treated mandible fractures from 2008 to 2017 with sufficient follow-up were retrospectively analyzed for information about the fracture condition, treatment, and outcomes.ResultsA total of 126 surgically-treated mandible fractures without mandibular condylar fracture in 105 patients (76 male, 29 female) were included. Reconstruction plates were used in 32 fractures with very good postoperative occlusal function. Four cases with complications requiring reoperation were treated using only miniplates. Variables that were statistically associated with follow-up surgery included simple versus comminuted mandible fracture, and the absence of teeth that could be used for intermaxillary fixation (P < 0.05). In the miniplates treatment for comminuted fracture, there was a significant difference in the treatment outcome depending on the number of free bone-fragments and the presence of bone-fragments requiring removal within 1 cm (P < 0.05).ConclusionReconstruction plates provided better treatment outcomes for comminuted fractures and fractures without teeth. Selecting a reconstruction plate that is capable of sufficiently overloading is important in comminuted fractures with multiple free bone-fragments and bone-fragments requiring removal.  相似文献   
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