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1.
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   
2.
Background: Tacrolimus (FK506) is currently used as the primary immunosuppressant in clinical kidney transplantation in some centers. The purpose of this study was to evaluate the pharmacokinetics of this drug and to see if trough level, which has been used widely in therapeutic drug monitoring, can be used as an appropriate substitute for other pharmacokinetic measurement tests. Methods: The blood concentration-time curve was studied in 10 kidney transplant recipients on 26 Occasions after oral dosage of 2 to 18 mg every 12 hours. Whole blood concentration was measured by two-step irnmunoabsorption assay. Methylprednisolone was used as a concomitant immuno-suppressive drug. Results: The blood concentration-time curves showed remarkable interindividual variation. lntraindividual variation was also found, but the degree of variation was slight compared with interindividual variation. On 17 occasions of measurement in one patient, the dose was significantly correlated with trough (r = 0.684). Cmax (r = 0.838) and AUC0–12 (r = 0.817). In nine patients on nine occasions, however, the dose was not significantly correlated with trough (r = 0.351), Cmax (r = 0.270) or AUC0–12 (r = 0.355). tmax ranged from one to four hours (mean + SD; 2.8 + 1.3) and fluctuated in both intra- and interindividual measurements. In spite of a wide variation in the blood concentration-time-curve patterns, a highly significant linear relationship between trough and Cmax or AUC0–12 was observed in both intraindividual (Cmax, r = 0.876; AUC0–12, r = 0.926) and interindividual (Cmax, f = 0.943; AUC0–12, r = 984) measurements. Concluslons: We conclude that trough level is a practical acceptable indicator of the blood levels of tacrolimus, and can be used to monitor blood concentration.  相似文献   
3.
Culture of chondrocytes in fibroin-hydrogel sponge   总被引:5,自引:0,他引:5  
Fibroin-hydrogel sponge and collagen gel were used as scaffold for in vitro cartilage regeneration. Fibroin-hydrogel sponge was formed by phase separation from freezed fibroin solution. Chondrocytes were harvested from proximal humerus, distal femur and proximal tibia of 4-week-old Japanese white rabbits and inoculated in the fibroin-hydrogel sponge and collagen gel. Those constructs were cultured in DMEM supplemented with 10% FCS and 50 ml L-ascorbate at 37 degrees C. Histological observation, measurement of sulfated glycosaminoglycan and cell density were carried out at 3, 7, and 14 days after the cultivation. Well-defined cartilage tissue can be seen both in the fibroin-hydrogel sponge and in the collagen gel. The matrix was intensely stained by safranin-O and showed a metachromatic reaction in both group. However, the quantity of sulfated glycosaminoglycan and cell density of the fibroin-hydrogel sponge group were increased more rapidly than these of the collagen gel group. Thus, the chondrocytes proliferated in the fibroin sponge without losing their differentiated phenotype. It is possible that culture environment in the fibroin sponge was suitable for chondrocytes regeneration.  相似文献   
4.
An autopsy case of adult hepatoblastoma is presented. The patient was an 82-year-old male with chronic hepatitis of 7 years' duration. The liver tumor was detected 6 months before death. Autopsy revealed a large hepatic tumor occupying about 80% of the entire liver. Histologically, the tumor showed typical features of mixed epithelial- and mesenchymal-type hepatoblastoma. The epithelial component consisted of fetal and embryonal cell types. The mesenchymal component showed primitive spindle-shaped cells with various degrees of cellularity. Chondroid areas and a few foci of osteoid formation were also present.  相似文献   
5.
The function of the Fc receptors γ chain (FcRγ) for the expression of the T cell receptor (TCR) complex and for T cell development, especially for T cells localized in epithelia, was investigated by analyzing FcRγ-deficient mice. In wildtype mice, CD8αα+β?TCRαβ+ T cells of intestinal intraepithelial lymphocytes (i-IEL) utilized CD3ζ homodimers and ζ-FcRγ heterodimers, whereas CD8α α+β?TCRγδ+ i-IEL used ζ-FcRγ and FcRγ homodimers in the TCR complex. On the other hand, these T cells in FcRγ-deficient mice contained only ζ homodimers. The surface expression of the TCR complex was reduced in CD8αα+β?i-IEL and dendritic epidermal T cells (DETC) in these mice, whereas the development of these T cells was normal. The degree of reduction appeared to depend on the expression level of FcRγ. In contrast to these populations, TCRγδ+ intraepithelial T cells in reproductive organs (r-IEL) were dramatically decreased, suggesting that the development of r-IEL is FcRγ-dependent, probably due to the predominant usage of FcRγ homodimers in the TCR complex. These results indicate that the FcRγ chain contributes differently to the TCR expression and to the development of T cells localized in epithelia.  相似文献   
6.
An autopsy case of a 74-year-old male who had shown clinically hypothyroidism due to chronic atrophic thyroiditis (Hashimoto's thyroiditis), and pathologically necrotizing myopathy as a remote effect of gastric cancer was reported.
Morphological features of this necrotizing myopathy was those of carcinomatous myopathy rather than those of hypothyroid or diabetic myopathy.
As for the pathogenesis of the necrotizing myopathy (as a Group IV of polymyositis of Walton and Adams), the malignancy might have played an important role as a trigger of the secondary immunological abnormality upon a pre-exizting longstanding immune disorder of Hashimoto's thyroiditis. Pseudomembranous colitis, which was thought to be related to antibiotics (Lincomycin), was also briefly discussed.  相似文献   
7.
The long-term efficacy of lamivudine therapy in patients with hepatitis B virus (HBV) infection is still not clear. In this study, 20 non-cirrhotic Japanese patients infected with HBV received lamivudine therapy for more than 1 year and were followed for a median period of 8.5 years (range, 6.7-8.7 years). The rates of HBe antigen (HbeAg) negative, HBV-DNA undetectable, and alanine aminotransferase (ALT) normal level at the start of lamivudine were 55%, 25%, and 20% and 85%, 80%, and were 80%, respectively, at the last visit, including patients who received additional treatment. The values at the last visit tended to and were significantly higher than those at the start. The values improved at the last visit regardless of the emergence of YMDD motif mutant and continuation of lamivudine. YMDD mutant and biochemical relapse with mutant virus (breakthrough hepatitis) appeared in 65% and 45% during follow-up, respectively, but severe breakthrough hepatitis occurred in only 5%. Furthermore, 80% of patients who received additional treatment for breakthrough hepatitis, regardless of continuation of lamivudine, were ALT normal level at the last visit, in contrast to 25% untreated. HBsAg clearance occurred in two patients of the discontinuous lamivudine group with non-vertical transmission, who were relatively young. One was infected with HBV genotype C with breakthrough hepatitis and the other had no YMDD mutant and was infected with genotype D, a rare type in Japan. None developed cirrhosis or hepatocellular carcinoma (HCC) during follow-up. Our results suggest that long-term lamivudine therapy improves long-term prognosis, especially when additional treatment for breakthrough hepatitis is used.  相似文献   
8.
1,5-Anhydroglucitol (1-DG) has been known as an antimetabolic glucose analogue. Using gas chromatography, 1-DG was found to be physiologically present in rat serum. In order to investigate its direct and long-term effects on feeding, 1-DG was infused during the light period into the rat third ventricle in doses of 3.0, 6.0 and 12.0 mumol/rat. Its effects were then compared to those of similarly applied 2-deoxy-D-glucose (2-DG). Following initial hyperphagia, both of these glucose-analogues produced suppressive effects on feeding during the subsequent day throughout the light and dark periods. On the third day after 2-DG injection reduction of feeding did not recover completely to the pretreatment baseline levels, but it did recover after 1-DG. Both 1-DG and 2-DG caused linear dose-related hypophagia, with the slope for 1-DG being about half of that for 2-DG. It is suggested that the delayed hypophagia which followed the initial hyperphagia produced by deoxyglucose was a result of sustained inactivation of the Na-pump due to intracellular ATP deficiency caused by accumulation of deoxy-glucose-6-phosphate.  相似文献   
9.
10.
Background: We assessed the efficacy and anticarcinogenic effects of interferon (IFN) therapy in patients with hepatitis C virus (HCV)-related cirrhosis. Methods: The study subjects were 123 Japanese patients with HCV-related cirrhosis with genotype 1b low viral load or genotype 2 who received IFN from 1989 to 2005 (18 patients continue to receive IFN therapy). They included 81 men and 42 women aged 29-74 years (median, 56 years). Results: Univariate analysis identified four parameters that significantly influenced SVR; viral load (low HCV concentration, P < 0.001), duration of IFN therapy (>/= 52 weeks, P = 0.029), daily dose of IFN (>/= 6 million units, P = 0.018), induction therapy (presence, P = 0.010) and choline esterase (> 1.0 DeltapH, P = 0.037). Multivariate analysis identified viral load (risk ratio = 6.329, P < 0.001) and daily dose of IFN (risk ratio = 2.62, P = 0.042) as two independent parameters thatinfluenced SVR. During the observation period, newly developed hepatocellular carcinoma (HCC) was detected in 22 patients. The rates of development of HCC in patients with SVR were 5.8% at the fifth year and 10.3% at the 10th year, compared with 25.8% at the fifth year and 42.5% at the 10th year in non-SVR patients. Multivariate analysis showed that IFN efficacy (SVR) was the only independent factor of hepatocarcinogenesis (hazard ratio: 0.185, 95% confidence interval: 0.042-0.810, P = 0.025) Conclusion: Among patients with HCV-related cirrhosis, the rate of development of HCC is significantly less in patients with SVR.  相似文献   
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