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41.
Type 1 diabetes triggers protein kinase C (PKC)-dependent NADPH oxidase activation in the renal medullary thick ascending limb (mTAL), resulting in accelerated superoxide production. As acute exposure to superoxide stimulates NaCl transport by the mTAL, we hypothesized that diabetes increases mTAL Na(+) transport through PKC-dependent and NADPH oxidase-dependent mechanisms. An O(2)-sensitive fluoroprobe was used to measure O(2) consumption by mTALs from rats with streptozotocin-induced diabetes and sham rats. In sham mTALs, total O(2) consumption was evident as a 0.34±0.03 U change in normalized relative fluorescence (ΔNRF)/min per mg protein. Ouabain (2 mmol/L) reduced O(2) consumption by 69±4% and 500 μmol/L furosemide reduced O(2) consumption by 58±8%. Total O(2) consumption was accelerated in mTAL from diabetic rats (0.74±0.07 ΔNRF/min/mg protein; P<0.05 versus sham), reflecting increases in ouabain- and furosemide-sensitive O(2) consumption. NADPH oxidase inhibition (100 μmol/L apocynin) reduced furosemide-sensitive O(2) consumption by mTAL from diabetic rats to values not different from sham. The PKC inhibitor calphostin C (1 μmol/L) or the PKCα/β inhibitor G?6976 (1 μmol/L) decreased furosemide-sensitive O(2) consumption in both groups, achieving values that did not differ between sham and diabetic. PKCβ inhibition had no effect in either group. Similar inhibitory patterns were evident with regard to ouabain-sensitive O(2) consumption. We conclude that NADPH oxidase and PKC (primarily PKCα) contribute to an increase in O(2) consumption by the mTAL during type 1 diabetes through effects on the ouabain-sensitive Na(+)-K(+)-ATPase and furosemide-sensitive Na(+)-K(+)-2Cl(-) cotransporter that are primarily responsible for active transport Na(+) reabsorption by this nephron segment.  相似文献   
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5q14.3 deletions including the MEF2C gene have been identified to date using genomic arrays in patients with severe developmental delay or intellectual disability, stereotypic behavior, epilepsy, cerebral malformations and a facial gestalt not really distinctive though characterized by broad and/or high, bulging forehead, upslanting palpebral fissures, flat nasal root and bridge, small, upturned nose, hypotonic small mouth resulting in cupid bow/tented upper lip. MEF2C mutations have been also identified in patients with overlapping phenotype so that it is considered the gene responsible for the 5q14.3 deletion syndrome. To date, one single duplication including MEF2C has been reported in a patient with intellectual disability but its clinical significance remains uncertain also because of the large size of the imbalance. Here we present two further patients with 5q14.3 duplications including MEF2C. Their phenotype indeed suggest the pathogenic effect of the MEF2C duplication although other duplicated genes also brain expressed might contribute to the clinical features. In none of them a clear-cut syndrome can be identified. A comparison between MEF2C deleted/mutated and duplicated patients is also presented.  相似文献   
44.
To determine the effect of maternal anaemia on pregnancy outcome and describe its impact on infant haemoglobin level in the first 18 months of life, we conducted a prospective study of 617 pregnant women and their children in Benin. Prevalence of maternal anaemia at delivery was 39.5%, and 61.1% of newborns were anaemic at birth. Maternal anaemia was not associated with low birth weight [OR = 1.2 (0.6-2.2)] or preterm birth [OR = 1.3 (0.7-2.4)], whereas the newborn's anaemia was related to maternal anaemia [OR = 1.8 (1.2-2.5)]. There was no association between an infant's haemoglobin level until 18 months and maternal anaemia. However, malaria attacks during follow-up, male gender and sickle cell trait were all associated with a lower infant haemoglobin level until 18 months, whereas good infant feeding practices and a polygamous family were positively associated with a higher haemoglobin level during the first 18 months of life.  相似文献   
45.
Classification of juvenile idiopathic arthritis is an ongoing process and up to now has been predominantly based on clinical manifestations—mainly number of joints at onset of disease. In the meantime, basic studies have advanced our knowledge regarding the disease pathogenesis. Unfortunately, studies of cytokines and cytokine polymorphisms have not followed the predominantly clinical International League of Associations for Rheumatology classification in that no significant biological differences among the different disease categories have been demonstrated with robust associations. Only systemic-onset disease seems to be quite different from other disease categories with regard to biologic mechanisms; indeed, it now seems closer to autoinflammatory than to classic autoimmune diseases. New players in the immunologic basis of juvenile idiopathic arthritis (eg, interleukin-17 and regulatory T cells) are also discussed in this review.  相似文献   
46.
Erdheim-Chester disease is a rare non-langerhans cell histiocytosis characterized by infiltration of foamy CD68-positive but CD1a-negative macrophages and fibro-inflammatory lesions as retroperitoneal, periureteral areas or bones. Interferon-α therapy has been used as treatment but it had variable efficiency and limited tolerance. More recently, a recombinant form of interleukin-1 receptor antagonist (anakinra) was used with success but no skeletal radiological improvement was recorded. We report here a case of interleukin-1 receptor antagonist in the treatment of refractory bones infiltration in Erdheim-Chester disease. After 1 year of treatment, the positron emission tomography-computed tomography showed an outstanding response of the skeletal involvement with clearly lower and smaller hypermetabolism images.  相似文献   
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The aim of this study is to assess the long-term effectiveness and safety of IL1Ra in Schnitzler syndrome (SchS). Between 2010 and 2012, we performed a nationwide survey among French internal medicine departments to identify SchS patients. We retrospectively analyzed the long-term efficacy and safety of IL1Ra and the outcome of patients that did not receive this treatment. Forty-two patients were included in the study, 29 of whom received IL1Ra. The mean age at disease onset was 59.9 years. Disease manifestations included urticaria (100%), fever (76%), bone/joint pain (86%), bone lesions (76%), anemia (67%), and weight loss (60%). The monoclonal gammopathy was overwhelmingly IgM kappa (83%). The mean follow-up was 9.5 years (range: 1.6-35). Two patients developed Waldenström's macroglobulinemia and one developed AA amyloidosis. All of the 29 patients who received IL1Ra responded dramatically. After a median follow-up of 36 months (range: 2-79), the effectiveness remained unchanged. All patients remained on anti-IL-1 therapy. Twenty-four patients (83%) went into complete remission and five (17%) into partial remission. Three patients experienced grade 3-4 neutropenia. Six patients developed severe infections. No lymphoproliferative diseases occurred while on IL1Ra. When last seen, all patients without anakinra had an active disease with variable impact on their quality of life. Their median corticosteroids dosage was 6 mg/d (range: 5-25). IL1Ra is effective in SchS, with a sharp corticosteroid-sparing effect. Treatment failures should lead to reconsider the diagnosis. Long-term follow-up revealed no loss of effectiveness and a favorable tolerance profile. The long-term effects on the risk of hemopathy remain unknown.  相似文献   
50.
We performed p53 immunohistochemistry, DNA flow cytometry and analysis of the argyrophilic nucleolar organizer regions (AgNORs) in formalin-fixed, paraffin-embedded sections from 46 non-invasive thymomas and correlated the results with the traditional clinicopathologic features of the tumor. p53 immunopositivity was detected in 21 of 46 cases; it was not associated with any clinicopathologic features nor DNA content but significantly correlated with AgNOR counts. On univariate analysis, 10-year survival rates were 100% for p53-negative cases but only 71% for p53-positive cases and 93% for patients with low AgNOR counts but only 77% for patients with high AgNOR counts. Age, sex, histologic type, myasthenia gravis and DNA content did not correlate with survival. Our results indicate that p53 staining and evaluation of proliferative activity allow assessment of prognosis in non-invasive thymomas, when all of the other parameters are insufficient. Furthermore, the high rate of p53 expression in non-invasive thymomas suggests that abnormal p53 immunoreactivity may occur early in the neoplastic process. © 1996 Wiley-Liss, Inc.  相似文献   
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