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Clinical Rheumatology - To investigate the characteristics, evolution, and visual outcome of non-infectious uveitis. Records of 201 patients with non-infectious uveitis (136 (67.7%) males and 84...  相似文献   
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This work attempts to recognize the Arabic vowels based on facial electromyograph (EMG) signals, to be used for people with speech impairment and for human computer interface. Vowels were selected since they are the most difficult letters to recognize by people in Arabic language. Twenty subjects (7 females and 13 males) were asked to pronounce three Arabic vowels continuously in a random order. Facial EMG signals were recorded over three channels from the three main facial muscles that are responsible for speech. The EMG signals are then pre-processed to eliminate noise and interference signals. Segmentation procedure was implemented to extract the time event that corresponds to each vowel based on a moving standard deviation window. The accuracy of the segmentation procedure was found to be 94%. The recognition of the vowels was carried out by extracting features from the EMG in three domains: the temporal, the spectral, and the time frequency using the wavelet packet transform. Classification of the extracted features was then finally performed using different classification methods implemented in the WEKA software. The random forest classifier with time frequency features showed the best performance with an accuracy of 77% evaluated using a 10-fold cross-validation.  相似文献   
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Defects of respiratory chain complex III (CIII) result in characteristic but rare mitochondrial disorders associated with distinct neuroradiological findings. The underlying molecular defects affecting mitochondrial CIII assembly factors are few and yet to be identified. LYRM7 assembly factor is required for proper CIII assembly where it acts as a chaperone for the Rieske iron–sulfur (UQCRFS1) protein in the mitochondrial matrix and stabilizing it. We present here the seventeenth individual with LYRM7-associated mitochondrial leukoencephalopathy harboring a previously reported rare pathogenic homozygous LYRM 7 variant, c.2T>C, (p.Met1?). Like previously reported individuals, our 5-year-old male proband presented with recurrent metabolic and lactic acidosis, encephalopathy, and fatigue. Further, he has additional, previously unreported features, including an acute stroke like episode with bilateral central blindness and optic neuropathy, recurrent hyperglycemia and hypertension associated with metabolic crisis. However, he has no signs of psychomotor regression. He has been stable clinically with residual left-sided reduced visual acuity and amblyopia, and no more metabolic crises for 2-year-period while on the mitochondrial cocktail. Although the reported brain MRI findings in other affected individuals are homogenous, it is slightly different in our index, revealing evidence of bilateral almost symmetric multifocal periventricular T2 hyperintensities with hyperintensities of the optic nerves, optic chiasm, and corona radiata but with no cavitation or cystic changes. This report describes new clinical and radiological findings of LYRM7-associated disease. The report also summarizes the clinical and molecular data of previously reported individuals describing the full phenotypic spectrum.  相似文献   
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Phenotyping is commonly used for detection of extended-spectrum beta-lactamase (ESBL) production in gram-negative isolates. ESBLs are mainly coded for by four important genes, namely bla (TEM), bla (SHV), bla (CTX-M), and bla (OXA). Our aim in this study is to assess use of a multiplex PCR as a rapid method to identify four common genes responsible for ESBL production in different gram-negative isolates. All 793 clinical isolates are subjected to both screen and confirmatory testing for ESBL production using double disc synergy testing (DDST). Two hundred isolates with the ESBL phenotype are subjected to multiplex PCR for detection of the four genes bla (TEM, SHV, CTX-M, and OXA). The isolates were obtained from various clinical specimens: 68 (34 %) were isolated from urine cultures, 43 (21.5 %) from sputum, 26 (13 %) from wounds, 34 (17 %) from blood culture, 20 (10 %) from stool of healthy carrier and nine (4.5 %) from bronchoalveolar lavages. In this study, 83 isolates (41.5 %) were from outpatients (urine and stool specimens only), and the remaining 117 isolates (58.5) were from inpatients. By PCR technique, 181 isolates were found to be ESBL producers. blaTEM was the commonest genotype (39.2 %), followed by blaSHV (32.5 %) and blaCTX-M (30.9 %), either alone or in combination. Acinetobacter baumannii isolate had none of the ESBL genes. Eighteen (9.9 %) out of 181 isolates carried more than one type of beta-lactamase genes. Our study demonstrated rapid detection of bla (TEM, SHV, CTX-M, and OXA) in isolates belonging to Enterobacteriaceae and other nonfermenting clinical isolates using multiplex PCR. This genotypic method provided a rapid and efficient differentiation of ESBLs in the laboratory.  相似文献   
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Adipocyte-fatty acid binding protein (A-FABP) is a 14-15 kDa cytoplasmic protein that binds unesterified fatty acids (FA). It is believed that A-FABP is present in normal cells and disappears in cancer cells. Prostate cancer DU145 cells lack expression of A-FABP. Here, we report that transfection of A-FABP blocked growth of DU145 cells suggesting its role as a tumor suppressor. A-FABP transfected- prostate cancer DU145 cells underwent apoptosis when induced to overexpress A-FABP using an ecdysone-controlled expression system. DU145 cell cultures in complete medium exhibited a maximum of approximately 28% of apoptotic cells after 96 h of exposure to an ecdysone analog, Ponasterone A. We found that the possible mechanisms leading to the observed apoptotic effect may be due, in part, to an overexpression of tumor necrosis factor-alpha (TNF-alpha) and a moderate downregulation of transforming growth factor-alpha (TGF-alpha) in DU145 cells overexpressing A-FABP. The epidermal growth factor receptor (EGFR)/phosphatidyl inositol 3-kinase (PI 3-kinase) signaling pathway was not altered in these cells, suggesting that A-FABP may cause apoptosis by inducing downregulation of essential autocrine growth factors and/or upregulation of pro-apoptotic ones.  相似文献   
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Tumor necrosis factor-alpha (TNF-alpha) levels in supernatant fluid from cultured peripheral blood mononuclear cells (PBMC) were measured by ELISA in 54 children with active non-inherited forms of primary nephrotic syndrome (PNS), 10 nephrotics in remission, and 10 healthy controls. Children with active PNS included 21 patients with steroid-sensitive (SS) minimal change nephrotic syndrome (MCNS), 5 patients with steroid-resistant (SR) MCNS, 11 with SR focal segmental glomerulosclerosis (FSGS), 6 patients with SS diffuse mesangial proliferation (DMP), 5 patients with SR DMP, and 6 patients with mesangiocapillary glomerulonephritis (MCGN). Patients with active PNS had elevated TNF-alpha production compared with controls. Remission was associated with normalization of TNF-alpha production. There was a positive correlation between TNF-alpha production and the degree of proteinuria ( r=0.34, P=0.013), mesangial hypercellularity ( r=0.42, P=0.028), and glomerulosclerosis ( r=0.46, P=0.001). By using ROC curve, TNF-alpha production greater or equal to a cut-off point of 50 pg/ml could be used to predict resistance to steroid therapy (predictability 93.2%). By discriminate analysis, TNF-alpha production could be used to discriminate between patients with SR MCNS, SR FSGS, and SR DMP (predictability 100%). In conclusion, TNF-alpha from cultured PBMC might be involved in the pathogenesis of proteinuria as well as the pathological changes that occur in non-inherited forms of PNS. TNF-alpha levels in PBMC culture could be used to predict the pathological type of PNS and the response of these patients to steroid therapy.  相似文献   
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