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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: Measurement of muscle mass is useful for evaluating protein nutritional status. Various methods for estimating muscle mass in haemodialysis patients have recently been developed. METHODS: The validity of the estimate of creatinine production calculated with the creatinine kinetic model (CKM) was examined in 46 haemodialysis patients by comparing it with the actual creatinine production, this being determined from the sum of creatinine appearing in the dialysate and the estimated metabolic degradation. The correlation of various other muscle mass indices with creatinine production was also investigated in these patients. RESULTS: The estimate of creatinine production using CKM was significantly correlated with creatinine production calculated from the spent dialysate plus an estimate for the extra-renal creatinine degradation (r=0.90, P<0.001). A Bland-Altman analysis revealed that the mean prediction error for the estimate of creatinine production by CKM was +0.10 g/day and the limits of agreement were +0.34 to -0.14 g/day. The cross-sectional area of the thigh muscle measured by computed tomography (CT) was also significantly correlated with creatinine production (r=-0.86, P<0.01). In contrast, the correlations of 3-methylhistidine production measured in the spent dialysate, the mid-upper arm muscle circumference and the skeletal muscle mass estimated by an anthropometric prediction model with creatinine production were lower (r<0.82). CONCLUSION: Creatinine production calculated using CKM and CT measurement of thigh muscle area are valid methods for estimating muscle mass during routine clinical examinations of haemodialysis patients.  相似文献   
3.
BACKGROUND: Cyanide is a toxic agent, and its detoxification product, thiocyanate, may be a major pathogenetic substance in uraemia. Recent studies examining the myeloperoxidase(MPO)/thiocyanate system have suggested a link between thiocyanate and atherosclerosis. However, inaccuracies in conventional assays for cyanide and thiocyanate have limited the understanding of their metabolism in haemodialysis (HD) patients. METHODS: We used high-performance liquid chromatography to measure cyanide in erythrocytes and thiocyanate in plasma in 43 HD patients and in a group of 46 healthy controls that included 15 current smokers. To clarify the metabolic conversion of cyanide to thiocyanate in uraemic patients, we also measured cysteine and sulfate. We then used stepwise regression analysis to analyse factors that determine erythrocyte cyanide and plasma thiocyanate. RESULTS: Mean cyanide and thiocyanate were significantly greater in HD patients than in non-smoking controls. However, cyanide was far below lethal concentrations in dialysis patients. Thiocyanate was six to seven times greater in HD patients than in non-smoking controls, and decreases in thiocyanate following dialysis were only 19.3+/-3.5%. Multiple regression analysis showed a positive correlation between cyanide and thiocyanate in controls, but a negative correlation in HD patients. In patients, an inverse relationship between thiocyanate and BUN was also observed. CONCLUSIONS: The elevation of thiocyanate in patients undergoing dialysis probably is secondary to both limited efficiency of HD and deranged metabolism of cyanide and thiocyanate. Because thiocyanate is a preferred substrate for MPO, it may play a role in uraemic complications including cardiovascular events.  相似文献   
4.
We previously reported that the Guardian Bio-Threat Alert (BTA) system could detect (detection limit: about 0.1 μg/ml) staphylococcal enterotoxin B (SEB), botulinum toxins (BTX) A and B, and ricin, with no interference by white-powdered materials or colored matrices. In this study, the capability of the BTA system was further assessed. With 10 min of preheating at 60°C, all toxins could be detected, but with preheating at 80°C, BTX A and B and ricin became undetectable. About 20% SEB could be detected after heating at 80°C, but this detection ability was completely removed after heating at 100°C. The effects of chemicals usually used for decontamination, such as sodium hypochlorite, hydrogen peroxide, formaldehyde, and sodium nitrite, on the detectability of SEB, BTX A, or ricin in the BTA system were also tested. The concentrations giving 50% line intensity for SEB, BTX A, and ricin were 3.1, 11, and 15 μM for sodium hypochlorite and 88, 210, and 60 mM for formaldehyde, respectively. The addition of hydrogen peroxide or sodium nitrite did not decrease the detectability even when used at high concentrations.  相似文献   
5.
Recent studies have suggested that aldosterone plays a role in the pathogenesis of renal injury. In this study, we investigated whether local angiotensin II (Ang II) activity contributes to the progression of renal injury in aldosterone/salt-induced hypertensive rats. Uninephrectomized rats were treated with 1% NaCl in a drinking solution and one of the following combinations for 6 weeks: vehicle (2% ethanol, s.c.; n=9), aldosterone (0.75 mug/h, s.c.; n=8), aldosterone+Ang II type 1 receptor blocker olmesartan (10 mg/kg/day, p.o.; n=8), or aldosterone+olmesartan (100 mg/kg/day, p.o.; n=9). Aldosterone/salt-treated hypertensive rats exhibited severe proteinuria and renal injury characterized by glomerular sclerosis and tubulointerstitial fibrosis. Aldosterone/salt-induced renal injury was associated with augmented expression of angiotensin converting enzyme and Ang II levels in the renal cortex and medullary tissues. Renal cortical and medullary mRNA expression of transforming growth factor-beta (TGF-beta) and connective tissue growth factor (CTGF) as well as the collagen contents were increased in aldosterone/salt-treated hypertensive rats. Treatment with olmesartan (10 or 100 mg/kg/day) had no effect on blood pressure but attenuated proteinuria in a dose-dependent manner. Olmesartan at 10 mg/kg/day tended to decrease renal cortical and medullary Ang II levels, TGF-beta and CTGF expression, and collagen contents; however, these changes were not significant. On the other hand, an ultrahigh dose of olmesartan (100 mg/kg/day) significantly decreased these values and ameliorated renal injury. These data suggest that augmented local Ang II activity contributes, at least partially, to the progression of aldosterone/salt-dependent renal injury.  相似文献   
6.
We report a 73-year-old woman with typical clinical, histological and immunofluorescence features of pemphigoid nodularis. Direct immunofluorescence studies of prurigo nodularis-like lesions and peribullous skin showed the linear deposition of IgG and C3 at the basement membrane zone. Circulating IgG against the basement membrane was also detected by indirect immunofluorescence. The serum from the patient was shown to contain the autoantibody against 230 kDa hemidesmosomal antigen associated with bullous pemphigoid antigen.  相似文献   
7.
The history of the documentation of health inequality is long. The way in which health inequality has customarily been documented is by comparing differences in the average health across groups, for example, by sex or gender, income, education, occupation, or geographic region. In the controversial World Health Report 2000, researchers at the World Health Organization criticized this traditional practice and proposed to measure health inequality across individuals irrespective of individuals’ group affiliation. They defended its proposal on the moral grounds without clear explanation. In this paper I ask: is health inequality across individuals of moral concern, and, if so, why? Clarification of these questions is crucial for meaningful interpretation of health inequality measured across individuals. Only if there was something morally problematic in health inequality across individuals, its reduction would be good news. Specifically, in this paper I provide three arguments for the moral significance of health inequality across individuals: (a) health is special, (b) health equity plays an important and unique role in the general pursuit of justice, and (c) health inequality is an indicator of general injustice in society. I then discuss three key questions to examine the validity of these arguments: (i) how special is health?, (ii) how good is health as an indicator?, and (iii) what do we mean by injustice? I conclude that health inequality across individuals is of moral interest with the arguments (b) and (c).  相似文献   
8.
9.
Developments in the treatment of childhood cancer have beenevaluated in patients who had been treated in the National Children'sHospital from 1965 to 1987. The total number of patients was867, of which leukemia accounted for 376, malignant lymphoma61, neuroblastoma 174, Wilms' tumor 55, yolk sac tumor 29, rhabdomyosarcoma36 and hepatoblastoma 30. Patients were divided into three timeintervals: the 1960s, 1970s and 1980s. A marked improvementin five-year survival was recognized in Wilms' tumor and yolksac tumor, amounting to 80%, followed by rhabdomyosarcoma, acutelymphoblastic leukemia and malignant lymphoma. There was noimprovement in patients with acute non-lymphoblastic leukemia,neuroblastoma and hepatoblastoma. Prognostic factors for neuroblastomawere further analyzed, and the age of onset and stage of diseasewere found to have remained constant for 23 years. Factors relatingto the improvement of survival were discussed.  相似文献   
10.
The development of gut-associated lymphoid tissue (GALT) in the rat was investigated, with special reference to the behavior and ultrastructure of Ia(+) cells during the development of Peyer's patches (PP). At birth, Ia(+) cells were randomly scattered in the lamina propria. From three days, small aggregates of CD4(+), Ia(+), CD5(−) and IL-1(+) cells were observed in the lamina propria. Immunoelectron microscopically, these appeared as mixed populations of dendritic cells, capillary endothelial cells, flbroblast-like spindle cells and lymphocytes. In addition, CD8(+), CD4(–) and IL-1(−) cells were present in the interepithelial space. By seven days, lymphoid follicles were recognizable in the lamina propria, each with an aggregate of IgM-positive small lymphocytes at its center, surrounded by CD4(+) or CD8(+) lymphocytes. Between the 10th and 14th days, these follicles were covered with single-layered, specially differentiated epithelial cells, and structures resembling PP were formed. IgA plasma cells were identified in the lamina propria between the third and the fourth weeks. We speculate that the PP developed from aggregates of Ia(+), IL-1(+) spindle- or dendritic-shaped cells in the lamina propria. The PP were structurally complete by two weeks, although establishment of the characteristic distribution of GALT components evident in the adult took more than six weeks.  相似文献   
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