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51.
The association of HLA-DRB, DQA1, DQB1 alleles and haplotype frequency in Iranian patients with pulmonary tuberculosis. 总被引:3,自引:0,他引:3
A A Amirzargar A Yalda M Hajabolbaghi F Khosravi H Jabbari N Rezaei M H Niknam B Ansari B Moradi B Nikbin 《The international journal of tuberculosis and lung disease》2004,8(8):1017-1021
OBJECTIVES: To investigate HLA-DRB1, DQA1 and DQB1 allelic polymorphism in Iranian patients with pulmonary tuberculosis (PTB). METHODS: Forty patients with smear-positive PTB and 100 healthy individuals as a control group were studied for MHC class II allelic polymorphism by polymerase chain reaction with sequence-specific primers (PCR-SSP). The primer was supplied by biotest in the standard kit. DRB low resolution SSP and DQA, DQB intermediate resolution SSP was applied. RESULTS: The comparison of the patients and the control group showed a significant increase in the frequency of the HLA-DRB1*07 and DQA1*0101 alleles (OR 2.7, 95%CI 1.19-6.13, P = 0.025 and OR 2.66, 95%CI 1.15-6.44, P = 0.04, respectively) in the patient group. The frequency of DQA1*0301 and DQA1*0501 was also significantly decreased (OR 0.254, 95%CI 0.075-0.865, P = 0.033 and OR 0.53, 95%CI 0.3-0.95, P = 0.045, respectively) in the PTB patients. Concerning haplotype frequency, DRB1*11501, QDQA1*0103 and DQB1*0601 were increased, but this difference was not statistically significant. In the DQB1 locus, DQB1*0501 was non-significantly over-represented. CONCLUSIONS: HLA-DRB1*07 and HLA-DQA1*0101 appeared to be the predisposing alleles and HLA-DQA1*0301 and 0501 the protective alleles in our patients with TB. 相似文献
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Serum leptin concentrations during severe protein-energy malnutrition: correlation with growth parameters and endocrine function 总被引:3,自引:0,他引:3
Soliman AT ElZalabany MM Salama M Ansari BM 《Metabolism: clinical and experimental》2000,49(7):819-825
Circulating leptin, insulin, insulin-like growth factor-I (IGF-I), cortisol, and albumin concentrations and the growth hormone (GH) response to provocation were measured in 30 children with severe protein-energy malnutrition (PEM), 20 with marasmus and 10 with kwashiorkor, as well as 10 age-matched normal children (body mass index [BMI] >50th and <90th percentile for age and sex) and 10 prepubertal obese children (BMI >95th percentile for age and sex). Patients with PEM had a significantly lower BMI, midarm circumference (MAC), and skinfold thickness (SFT) compared with the age-matched control group. Basal cortisol and GH concentrations were significantly higher in the malnourished groups versus controls. Leptin and IGF-I were significantly lower in the marasmic and kwashiorkor groups versus normal children. Fasting insulin levels were significantly decreased in the kwashiorkor group compared with marasmic and normal children. The BMI correlated significantly with leptin (r = .77, P < .001), basal insulin (r = .61, P < .001), and IGF-I (r = .77, P < .001) and negatively with basal GH (r = -.52, P < .001). These findings suggest that during prolonged nutritional deprivation, the decreased energy intake, diminished subcutaneous fat mass, and declining insulin (and possibly IGF-I) concentration suppress leptin production. In support of this view, serum leptin levels were positively correlated with triceps, scapular, and abdominal SFT (r = .763, .75, and .744, respectively, P < .0001) in all of the children. Moreover, basal insulin and circulating IGF-I were correlated significantly with leptin concentrations (r = .47 and .62, respectively, P < .001). Basal levels of cortisol and GH were significantly elevated in the 2 groups with severe PEM. It is suggested that low leptin levels can stimulate the hypothalamic-pituitary-adrenal (HPA) axis and possibly the hypothalamic-pituitary-GH axis to maintain the high cortisol and GH levels necessary for effective lipolysis to ensure a fuel (fatty acids) supply for the metabolism of brain and peripheral tissue during nutritional deprivation. In summary, during prolonged PEM, the decreased synthesis of IGF-I and the low level of insulin and/or its diminished effect due to an insulin-resistant status in the presence of high circulating GH and cortisol levels ensure substrate diversion away from growth toward metabolic homeostasis. Leptin appears to be an important signal in the process of metabolic/endocrine adaptation to prolonged nutritional deprivation. 相似文献
54.
Vascular manifestations of systemic lupus erythematosus 总被引:2,自引:0,他引:2
Systemic lupus erythematosus (SLE) is a well-known acute and/or chronic multisystem disease of complex autoimmune nature, having predilection for cardiovascular system. While its cardiac manifestations have been adequately studied, there is paucity of information on its vascular manifestations. Accordingly, we studied the incidence of vascular manifestations in 50 consecutive SLE patients seen at our institutions and in private practice during the past 12 years. Systemic hypertension (44%) was the most common vascular manifestation followed by vasculitis (30%), Raynaud's phenomenon (26%), telangiectasis (20%), premature coronary atherosclerosis (6%), digital ulceration (6%), thrombophlebitis (6%), pulmonary hypertension (4%) and portal hypertension (4%). Diffuse systemic vasculitis similar to polyarteritis nodosa was rare (2%). Often more than one lesion was found in the same patient. The clinical diagnosis of these vascular manifestations in the context of the primary disease (SLE) usually does not pose any difficulty except when they antedate it. We also studied the pathology and pathogenesis of some of these vascular lesions in both autopsy and biopsy specimens by both light microscopy and immunofluorescent techniques. Our results as well as those of others who also studied these lesions indicate that immune complex deposition and subsequent complement activation play an important role in the pathogenesis of vasculitis, coronary arteritis and premature coronary atherosclerosis. Corticosteroids and vasodilators remain the drugs of choice for the management of the majority of the symptoms arising from the vascular lesions of SLE. 相似文献
55.
G L Hung M E Siegel C McKay D C Chen A N Ansari N B Arnstein K H Lee C A Stewart S H Rahimtoola 《Angiology》1990,41(11):901-907
Methodology for the computer analysis of 201T1 myocardial perfusion images has been developed by several laboratories. Substantial evidence of the advantage of this approach over visual inspection alone has been reported. The currently available computer analyses use different algorithms to analyze 201T1 kinetics in the myocardium. The authors evaluated and compared two widely used software programs, Medical Data System (MDS): a mean-count profile, and the Cedars Sinai (CS): a maximal-count profile, of planar 201T1 scintigraphy for their ability to detect coronary artery disease (CAD). 相似文献
56.
Faiza A. Rashid Sobia Tabassum Mosin S. Khan Hifzur R. Ansari Muhammad Asif Ahmareen K. Sheikh Syed Sameer Aga 《Journal of clinical laboratory analysis》2021,35(2)
Papillary thyroid carcinoma (PTC) is the most common endocrine malignancy among other endocrine tumors, and BRAF V600E is a frequent genetic mutation occurring in the disease. Although different molecular techniques, most importantly sequencing has been widely recognized as a gold standard but molecular diagnosis remains an expensive, laborious, and time‐intensive process. Recently, immunohistochemistry (IHC) with anti‐BRAF V600E (VE1) antibody has increased practical utility and implemented clinically for the detection of BRAF V600E mutation. Therefore, the study aimed to evaluate diagnostic accuracy of VE1 IHC for detecting the BRAF V600E mutation frequency and clinical implementation in diagnostic laboratories. In this study, 72 formalin fixed paraffin‐embedded tissues (FFPE) were used to determine the BRAF V600E mutation status using IHC and Sanger sequencing. The mutation was found in 29% and 28% cases using IHC and Sanger sequencing, respectively. Furthermore, the results showed 100% sensitivity, 98.07% specificity, 95.2% positive predictive value, and 100% negative predictive value. Notably, significant associations were found between BRAF V600E status and tumor stage, tumor focality, and extrathyroidal extensions, respectively. VE1 IHC was found to be a highly sensitive, specific, and diagnostically accurate method in this cohort. Therefore, BRAF V600E detection through IHC has been considered as the best tailored technique for routine pathology laboratories. 相似文献
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