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61.
The goal of this study was to apply temperature-mediated heteroduplex analysis using denaturing high-performance liquid chromatography to identify pyrazinamide (PZA) resistance in Mycobacterium tuberculosis isolates and simultaneously differentiate between M. tuberculosis and Mycobacterium bovis. Features that contributed to an optimal assay included the use of two different reference probes for the pncA gene targets from wild-type M. tuberculosis and wild-type M. bovis, optimization of the column temperature, increasing the starting concentration of the elution buffer, and reducing the rate of elution buffer increase (slope). A total of 69 strains were studied, including 48 wild-type M. tuberculosis strains (13 were PZA-resistant strains) and 21 M. bovis strains (8 were BCG strains). In all isolates tested, wild-type M. tuberculosis generated a single-peak pattern when mixed with the M. tuberculosis probe and a double-peak pattern with the M. bovis probe. In contrast, all M. bovis isolates generated a double-peak pattern when mixed with the M. tuberculosis probe and a single-peak pattern with the M. bovis probe. PZA-resistant mutant M. tuberculosis isolates generated characteristic patterns that were easily distinguishable from both wild-type M. tuberculosis and M. bovis isolates. Chromatographic patterns generated by the two reference probes allowed the rapid detection of PZA resistance with the simultaneous ability to distinguish between M. tuberculosis and M. bovis. This approach may allow the detection of drug resistance-associated mutations, with potential application to clinical and epidemiological aspects of tuberculosis control.  相似文献   
62.
We aimed at establishing hybridoma cells secreting monoclonal antibodies (mAbs) against E1 synthetic peptide of HCV. BALB/c mice were immunized with HCV E1-synthetic peptide (GHRMAWDMM) and its spleenocytes were fused with the P3NS1 myeloma cell line. Two highly reactive and specific mAbs (10C7 IgG2b mAb, and 10B2 IgG1 mAb) were generated. The target HCV E1 antigen was identified at approximately 38 kDa in serum of infected individuals. A newly developed ELISA detected the target antigen in 90% of sera from HCV RNA infected individuals with a specificity of 84%. So, the generated mAbs may provide promising probes for serodiagnosis of HCV infection.  相似文献   
63.

Background  

Gastro-Esophageal Reflux Disease (GERD) defined as a condition that develops when the reflux of stomach contents causes troublesome symptoms and/or complications. Many drugs are used for the treatment of GERD such as omeprazole (a proton pump inhibitor) which is a widely used antiulcer drug demonstrated to protect against esophageal mucosal injury. Melatonin has been found to protect the gastrointestinal mucosa from oxidative damage caused by reactive oxygen species in different experimental ulcer models. The aim of this study is to evaluate the role of exogenous melatonin in the treatment of reflux disease in humans either alone or in combination with omeprazole therapy.  相似文献   
64.
IntroductionGynecomastia denotes benign enlargement of the male breast. It is a common belief that gynecomastia is stigmatizing and may frequently cause social embarrassment and psychological stress. It is possible that this may reflect on erectile function of the afflicted. High grade gynecomastia requires radical breast tissue excision and skin reduction ending up in aesthetically unappealing scars.AimThe purpose of this study is to evaluate the reduction mammaplasty using no vertical scar technique in males with high grade gynecomastia; as regards technical refinements and outcome in the hope of providing a cosmetically appealing solution to this condition. This study also reports on the effect of high grade gynecomastia on erectile function, as well as the effect of surgery.MethodsFifteen male patients with gynecomastia underwent breast reduction using the “no vertical scar reduction mammaplasty.” Erectile function was evaluated before and after surgery.Main Outcome MeasuresSurgical outcome and erectile function.ResultsAll patients but one were satisfied with the outcome. Complications were minimal and manageable. Eleven out of 15 patients had a preoperative International Index of Erectile Function (IIEF) score less than 20 denoting erectile dysfunction. All but one (n = 10) showed improvement in their IIEF score following surgery. The difference between pre-operative IIEF (average 17.8) and postoperative (average 23.5) was statistically significant.ConclusionsThe “no vertical scar reduction mammaplasty” is a reliable technique in cases with gynecomastia and significant ptosis. It has the added benefits of avoiding the vertical scar, hiding the transverse scar in the shadow of the inferior aspect of the breast, with minimal complications. Gynecomastia as a condition causing a feminized outlook may have a negative impact on self confidence and body image. We suggest that this may have a potential negative effect on erectile function, that can be improved by adequate surgical correction. El Noamani S, Thabet AM, Enab AA, Shaeer O, and El-Sadat A. High grade gynecomastia: Surgical correction and potential impact on erectile function.  相似文献   
65.
Deep vein thrombosis (DVT) is a common multi-factorial disease, with serious short- and long-term complications, and a potential fatal outcome. Many genes are involved in determining the interindividual variation in traits that define the onset and progression of disease, as well as the response to treatment. Several association studies have designed the relationship between factor XII C46T polymorphism and the risk of arterial and venous thrombosis. Some studies reported that FXII gene polymorphism is not associated with venous thrombosis, whereas other studies found an increased risk of venous thrombosis in carriers of a FXII-T variant. We constructed an age–gender–ethnic–matched case–control study including 52 DVT patients and 100 healthy volunteers. C46T polymorphism of the coagulation factor XII was carried out using allelic discrimination assay by real-time polymerase chain reaction for patients and controls, while plasma factor XII activity was detected by one-step clotting assay. FXII C46T genotyping in DVT patients revealed that 34.6% were heterozygous harboring the FXII-CT heterotype and 3.85% were homozygous; FXII-TT homotype, with no statistically significant difference in the distribution of the mutant genotypes between DVT patients and the control group. FXII activity was significantly reduced in DVT patients harboring the mutant genotypes. In the present study, FXII C46T gene polymorphism was not associated with increased risk of deep venous thrombosis.  相似文献   
66.
Introduction. Hepatitis C virus (HCV) infection affects almost 3% of the world''s population with the highest prevalence in Egypt (15%). The standard therapy; pegylated interferon (PEG-IFN) and ribavirin, is effective in only 60% of Egyptian patients; moreover it is costly, prolonged, and has severe side effects, so prediction of response is essential to reduce burden of unfavorable treatment. Several viral and host factors have been proved to affect response to the treatment PEG-IFN and ribavirin; the strongest of them is polymorphisms near IL28B; nonetheless, nonresponse in patients with favorable IL28B is still unexplained, which implies the importance of studying other immunological factors that may correlate with response. Interleukin 12 (IL-12) is one of the most important proinflammatory cytokine presented with the initiation of immune response, determining Th1 and Th2 differentiation. A functional single nucleotide polymorphism (A/C) at the 3′ untranslated region (3′UTR) at position 1188 (NCBI SNP database no 3212227) was reported to be associated with responding more efficiently to antiviral combination therapy in HCV genotype 1 infected patients. The present study aims to evaluate association between this polymorphism with fibrosis stages, necroinflammation activity, response to the combined therapy, and gender in Egyptian HCV genotype 4. Material and Methods. A total of 133 Egyptian chronic HCV (CHCV) patients were treated with IFN/RBV and were followed up. IL12B 1188 A/C genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism (PRC-RFLP) analysis. Results. A nonsignificant trend for higher sustained virological response (SVR) was observed in patients homozygote for IL12B 1188 A/C SNP CC genotype (69% SVR versus 30.8% NR) only but not in AC and AA genotypes. No association was detected between IL12B 1188 A/C polymorphism and less severe fibrosis or less liver activity. By stratification of response according to gender genotype, a significant difference in response between males and females was seen among AA genotype carriers only due to high number of non responder females. Conclusion. IL12B CC genotype appears to have some influence on SVR achievement but not on severe fibrosis and severe necroinflamation activity. Females carrying A/A genotype of IL12B 1188 A/C SNP achieve less SVR than those carrying AC and CC genotypes.  相似文献   
67.
68.
Mycophenolate mofetil (MMF) is widely used for maintenance immunosuppression in solid organ transplantation. Gastrointestinal toxicity, usually manifested as diarrhea, is the most common side effect of MMF. We evaluated colonic biopsies from 20 renal transplant patients with MMF-related diarrhea. The latter was defined by the absence of any other demonstrable etiology and improvement or resolution of symptoms by the discontinuation or reduction of the dose of MMF alone. These biopsies were compared with colon biopsies from patients with the following: acute graft-versus-host disease (GVHD, n=10), inflammatory bowel disease (IBD) or infectious colitis (n=10), and colon biopsies from renal transplant patients not receiving MMF (n=8). Normal colonic segments from surgical specimens served as normal controls (n=5). Colonic biopsies from patients with MMF-related diarrhea showed prominent crypt cell apoptosis and reactive/reparative changes including enterocyte cytologic atypia, increased neuroendocrine cells, and glandular architectural distortion. The changes were similar, although of milder degree to the ones seen in patients with acute intestinal GVHD. This pattern of injury was not seen in controls or in biopsies from transplant patients not receiving MMF, and it was markedly different from the one seen in idiopathic inflammatory or infectious colitis. The severity of histologic changes correlated significantly with the endoscopic degree of "colitis." There was no statistically significant correlation between histologic damage and the dose of MMF (corrected for body weight and renal function). MMF-related colitis is a distinct entity that displays histologic features remarkably similar to the ones associated with intestinal GVHD. This form of injury could be related to either direct toxicity or an "innocent by-stander" phenomenon secondary to the alteration of the immunologic microenvironment of the colon caused by the MMF.  相似文献   
69.
BACKGROUND: Asthma in school children is rising, and indoor allergens are very common triggers of asthma attacks; however, the risk of the school environment on asthma has not been well studied. OBJECTIVE: To determine the presence and the levels of common aeroallergens in schools, where asthma prevalence rates are high. METHODS: Settled dust samples were collected from 12 Baltimore City public elementary schools, and they were analyzed for the following allergens: cockroaches (Bla g 1/2), dust mites (Der f 1/p 1), dog (Can f 1), cat (Fel d 1), and mouse (Mus m 1). School asthma prevalence rates were correlated with allergen levels, and association between allergen levels and other risk factors present in the schools' environment was examined. RESULTS: The mean and range levels were 1.49 U/g (0 to 8) for Bla g 1/2; 0.38 microg/g (0 to 11.9) for the Der f 1/p 1; 1.44 microg/g (0.1 to 9.6) for Can f 1; 1.66 microg/g (0.2 to 12) for Fel d 1; and 6.24 microg/g (0.3 to 118.3) for Mus m 1. Dust mite, cat and dog allergens were significantly in rooms with carpet and/or area rugs, compared to rooms with bare floors (P < 0.05). Asthma prevalence rates varied from 11.8 to 20.8% between schools and positively correlation with the mean levels of Bla g 1/2 in the schools (P = 0.001). CONCLUSIONS: Common allergens that are known to trigger asthma were detected in all school environments, where asthma prevalence rates were high. However, the overall allergen levels were low, indicating that other factors, including exposures in the homes of asthmatic patients, may have more relevance to sensitization and symptoms than school exposures.  相似文献   
70.
Epidermal growth factor receptor (EGFR) exon 18-21 mutations were shown to be highly predictive of response to gefitinib (Iressa) therapy in lung cancer. Studies on Western and Japanese lung cancers have indicated substantial differences in the EGFR mutation frequency between these populations. To investigate the prevalence of EGFR in another distinct ethnic group, EGFR alterations were studied in 47 consecutive non small cell lung cancers from Saudi Arabia by immunohistochemistry, fluorescence in situ hybridization, and DNA sequencing. Detectable EGFR expression was seen in 69.8% of 43 interpretable cancers. Epidermal growth factor receptor amplification, present in 15.3% of 39 analyzable cancers, was strongly associated with high levels of EGFR expression (P = .0047). Only 1 exon 18-21 mutation was seen among 34 lung cancers that could be successfully sequenced. It is concluded that EGFR exon 18-21 mutations are rare in Middle East patients with lung cancer and occur in a similar range as in Western patients. The remarkable high rate of EGFR gene amplifications could potentially facilitate studies on the predictive role of gene copy number changes for response to anti-EGFR therapies in Middle East patient sets.  相似文献   
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