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OBJECTIVES: To reveal the frequency and the clinical characteristics of dystrophic calcification that occurs in children with juvenile dermatomyositis, multi-center analysis was constructed. METHOD: Fifty children with JDM were enrolled, and 14 of them (28.0%) were complicated with calcinosis. Clinical symptoms and laboratory tests at onset, initial therapy and disease course were compared in children with and without calcinosis. RESULTS: The mean age of the onset of calcinosis was 4.78 +/- 3.33 years, and it was younger than those of children without calcinosis (8.66 +/- 3.85 years) (P = 0.0017). No differences of clinical manifestation except Gower's sign were observed. The frequency of positive anti-nuclear antibody was 7.1% in children with calcinosis and 52.9% without calcinosis (P = 0.0112). The initial therapy of methylprednisolon pulses gave no effects on prognosis of calcium deposition. The calcinosis appeared in 1.56 +/- 1.91 year after the onset of the disease. The various types of calcium deposition including large tumorous clumps, subcutaneous plaques or nodules, sheet-type calcification were deserved. They appeared over knee joints (64.3%), elbow joint (64.3%), and hip processes (50.0%). Calcinosis affecting the subcutaneous tissues frequently resulted in painful superficial ulceration of the overlying skin (42.9%), local infection (50.0%), and limitation of joint movement (14.3%). Although aluminum phosphate was effective in 2 children among 7, no other effective treatment was recommended. In 5 cases, surgical removal of tumorous clumps was operated. Thus, juvenile dermatomyositis is frequently complicated with calcinosis. This type of calcinosis was found to be unlikely to resolve completely, and resulted in severe disability in children.  相似文献   
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OBJECTIVES: To determine the value of the loss of expression of E-cadherin and cadherin associated molecules as useful markers for both prognosis and chemosensitivity in bladder cancer patients who have undergone radical cystectomy. PATIENTS AND METHODS: In 55 paraffin embedded specimens of radical cystectomy at our hospital from 1982 to 2000, the expression of E-cadherin, alpha-, beta- and gamma-catenin was examined by immunohistochemical staining. To evaluate the prognostic significance of these molecules, Kaplan-Meier survival curves were constructed and a statistical analysis was calculated by a log-rank test. A multivariate test (tumor stage, tumor grade, lymph node metastasis, configuration, the expression of E-cadherin, alpha-, beta- and gamma-catenin) was performed to detect prognostic markers. RESULTS: Normal expression was found in 33 cases (60.0%) for E-cadherin, 29 (52.7%) for alpha-catenin, 31 cases (56.4%) for beta-catenin, and 31 cases (56.4%) for gamma-catenin. The expression patterns for E-cadherin, alpha-, beta- and gamma-catenin were significantly correlated with each other (P < 0.01). Survival analysis showed a significant difference between normal and aberrant expression in each staining. A multivariate analysis revealed that the expression of alpha- catenin was an independent prognostic factor (P = 0.0191). In 23 patients that received adjuvant chemotherapy, there was a significant difference in survival between the normal and aberrant expression of alpha-catenin, but not other molecules. CONCLUSION: Alpha-catenin may not only be a good prognostic marker, but also one of key molecules that determine the chemosensitivities in patients with invasive bladder cancer.  相似文献   
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OBJECTIVE: Although hypercalciuria, a well-established adverse effect of vitamin D3, can be a risk factor of renal stone formation, the risk of nephrolithiasis has not been well defined. The consumption of a diet high in acid precursors is often cited as a risk factor for the development of calcium-based kidney stones. In the present study, we investigated the effect of chronic acid ingestion on kidney stone formation in rats treated with calcitriol (1-25[OH]2 D3). METHODS: Control rats (C-C), calcitriol-treated rats (C-V; three treatments of 0.5 microg of calcitriol per week) and acid-ingested (water containing 0.21 mol/L NH4Cl), calcitriol-treated (three treatments of 0.5 microg of calcitriol per week) rats (A-V) were fed in metabolic cages. After 1 month, urine, blood, kidney and bone samples were analyzed. RESULTS: The A-V rats exhibited elevated serum calcium concentrations, urinary calcium and phosphate excretion, urinary type I collagen cross-linked N-peptide (NTx)/creatinine values, mRNA expression of osteopontin in the kidney, and renal calcium contents as well as decreased bone mineral densities, compared with the C-C and C-V rats. Urinary citrate excretion was lower and NaDC-1 mRNA expression in the kidney was higher in the A-V rats than in the C-C and C-V rats. Calcium phosphate kidney stones were found in the A-V rats. CONCLUSIONS: The ingestion of NH4Cl, an acid precursor, promotes calcium phosphate kidney stone formation in calcitriol-treated rats. The chronic intake of a diet rich in acid precursors may be a risk factor for the development of kidney stones in subjects who are being treated with calcitriol.  相似文献   
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The spectral response curve (amplitude versus wavelength) of the R2 of the early receptor potential (ERP) was studied in normal, protan, and deutan subjects. The R2 amplitude peaked at 520nm in most normal subjects. The R2 at long wavelengths was smaller than normal in protans and larger than normal in deutans when the maximum amplitudes were normalized to 100% at the peak. The ratio of the R2 amplitude at 460 nm to that at 600 nm clearly differed between protans and deutans. The ERP and the rapid off-response, which is mainly due to the cessation of the late receptor potential, were recorded in the same subjects. The ratio of the sensitivity of the rapid off-response at 500 nm to that at 600 nm was correlated with the ratio of the R2 amplitude at 460 nm to that at 600nm (correlation coefficient, 0.823, p < 0.001). This study, in conjunction with our previous study, indicates that the abnormality is in the outer segments of the cones in protans and deutans.  相似文献   
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