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991.
992.
Background/Aims: Endoscopic definitions and management of Barrett's esophagus vary widely among countries. To examine the current situation regarding diagnosis, epidemiology, management and treatment of Barrett's esophagus in East Asian countries using a questionnaire-based survey. Methods: Representative members of the Committee of the International Gastrointestinal Consensus Symposium developed and sent a questionnaire to major institutions in China, South Korea, Japan, Thailand, Indonesia, and the Philippines. Results: A total of 56 institutions in the 6 countries participated in the survey. We found that the presence of specialized columnar metaplasia is considered to be important for diagnosing Barrett's esophagus in East Asian countries except for Japan. C&M criteria have not been well accepted in East Asia. The palisade vessels are mainly used as a landmark for the esophagogastric junction in Japan. The prevalence of long segment Barrett's esophagus is extremely low in East Asia, while the prevalence of short segment Barrett's esophagus is very high only in Japan, likely due to different diagnostic criteria. Conclusion: Among East Asian countries, we found both similarities and differences regarding diagnosis and management of Barrett's esophagus. The findings in the present survey are helpful to understand the current situation of Barrett's esophagus in East Asian countries.  相似文献   
993.
There is a critical need for improved diagnosis of tuberculosis in children, particularly in young children with intrathoracic disease as this represents the most common type of tuberculosis in children and the greatest diagnostic challenge. There is also a need for standardized clinical case definitions for the evaluation of diagnostics in prospective clinical research studies that include children in whom tuberculosis is suspected but not confirmed by culture of Mycobacterium tuberculosis. A panel representing a wide range of expertise and child tuberculosis research experience aimed to develop standardized clinical research case definitions for intrathoracic tuberculosis in children to enable harmonized evaluation of new tuberculosis diagnostic technologies in pediatric populations. Draft definitions and statements were proposed and circulated widely for feedback. An expert panel then considered each of the proposed definitions and statements relating to clinical definitions. Formal group consensus rules were established and consensus was reached for each statement. The definitions presented in this article are intended for use in clinical research to evaluate diagnostic assays and not for individual patient diagnosis or treatment decisions. A complementary article addresses methodological issues to consider for research of diagnostics in children with suspected tuberculosis.  相似文献   
994.
In most sexually reproducing animals, replication and maintenance of telomeres occurs in the germ line and during early development in embryogenesis through the use of telomerase. Somatic cells generally do not maintain telomere sequences, and these cells become senescent in adults as telomeres shorten to a critical length. Some animals reproduce clonally and must therefore require adult somatic mechanisms for maintaining their chromosome ends. Here we study the telomere biology of planarian flatworms with apparently limitless regenerative capacity fueled by a population of highly proliferative adult stem cells. We show that somatic telomere maintenance is different in asexual and sexual animals. Asexual animals maintain telomere length somatically during reproduction by fission or when regeneration is induced by amputation, whereas sexual animals only achieve telomere elongation through sexual reproduction. We demonstrate that this difference is reflected in the expression and alternate splicing of the protein subunit of the telomerase enzyme. Asexual adult planarian stem cells appear to maintain telomere length over evolutionary timescales without passage through a germ-line stage. The adaptations we observe demonstrate indefinite somatic telomerase activity in proliferating stem cells during regeneration or reproduction by fission, and establish planarians as a pertinent model for studying telomere structure, function, and maintenance.  相似文献   
995.
Chronic heart failure (HF) and chronic obstructive pulmonary disease (COPD) commonly coexist, and patients with both diseases fare worse than those with either disease alone. Several factors may contribute to worse outcomes, including an increased burden of care related to greater disease complexity, an overlap of symptoms resulting in misapplication of therapy, and the adverse effects of treatment for one disease on the symptoms and outcomes related to the other. For example, there are conflicting data about the cardiovascular risks of bronchodilators in HF patients who may experience worse outcomes with inhaled beta-2 agonists via arrhythmogenesis, ischemia, and/or attenuation of beta-blocker benefits. In contrast, the long-acting anticholinergic class of bronchodilators has a more reassuring safety profile. Anticholinergic bronchodilators may be the preferred first-line agents for COPD patients with comorbid HF, yet data supporting these recommendations are limited. Therapeutic trials in COPD patients have generally excluded patients with significant HF and vice-versa. This paper reviews bronchodilator therapy in HF and proposes a randomized trial designed to enroll patients with significant COPD and HF to determine the risks and/or benefits of adding a long-acting beta-2 agonist to patients currently taking a long-acting anticholinergic agent.  相似文献   
996.
997.
Aim of the workThe aim of the present study was to measure the level of the chemokine CXC ligand 13 protein (CXCL13) in the plasma and unstimulated saliva of rheumatoid arthritis (RA) patients in order to find out its role in the disease activity and its relation to secondary Sjögren’s syndrome (sSS).Patients and methodsThe study was conducted on thirty rheumatoid arthritis patients attending the Outpatient Clinic of Rheumatology and Rehabilitation department of Ain shams University Hospitals. The patients’ group had been classified into group (1) which included fifteen RA patients associated with sSS diagnosed according to the American–European Consensus Group Classification Criteria and group (2) which included fifteen RA patients not associated with sSS. Ten healthy subjects were included as a control group. Patients were subjected to full history taking, clinical examination, and laboratory detection of CXCL13 level in the plasma and saliva of patients as well as the control groups using ELISA technique. Assessment of disease activity in RA patients was done using the disease activity score (DAS28).ResultsPlasma levels of CXCL13 were significantly higher in RA patients than control group (p < 0.001). Plasma levels of CXCL13 were significantly correlated with the RA disease activity (r = 0.677, p < 0.001) and disease duration (r = 0.406, p < 0.05), while the salivary levels were higher in those with sSS and correlated with sSS disease duration (r = 0.536, p < 0.05). A highly significant correlation was found between salivary CXCL13 and severity of sSS (r = 0.816, p < 0.001). Salivary levels of CXCL13 above 110 pg/ml may diagnose sSS with sensitivity 80% and specificity 84%.ConclusionThe results of this preliminary study point out the importance of CXCL13 as a marker for RA disease activity, its role in diagnosing sSS, and estimation of sSS severity.  相似文献   
998.
Milk fat globule-epidermal growth factor 8 (MFG-E8), a glycoprotein secreted from various cells, enhances engulfment of apoptotic cells by forming a link between phosphatidylserine on apoptotic cells and α(v)β(3)-integrin on phagocytes. This process is essential for maintaining the host immune system under physiological conditions. Apart from this scavenging function, MFG-E8 also directly regulates a variety of cellular functions, such as attenuating inflammation and healing of injured tissues. Furthermore, recent studies have revealed that MFG-E8 has anti-inflammatory and regenerating roles during intestinal inflammation. This review highlights novel findings regarding the roles of MFG-E8 in intestinal pathophysiology as well as its therapeutic potential for gut inflammatory disorders.  相似文献   
999.

Background

While prevalence of Hepatitis B virus (HBV) in patients with end-stage renal failure (ESRF) who are undergoing dialysis has decreased significantly during the past few decades, it still remains a distinct clinical problem. The immunosuppressive nature of renal disease often leads to chronicity of the HBV infection and an opportunity for nosocomial spread of the infection among dialysis patients. Egypt is among the countries with intermediate endemicity of HBsAg (range, 2%–7%). Large-scale geographic heterogeneity in HBV prevalence has been reported worldwide and HBV prevalence is especially heterogeneous in Egypt.

Objectives

To assess the prevalence of occult HBV infection (OBI) in hemodialysis patients with or without chronic hepatitis C (HCV) from Minia and Assuit, Upper Egypt, using HBV DNA assays.

Patient and Methods

Sera from 145 hemodialysis patients with negative HbsAg were investigated for HBV DNA using real-time polymerase chain reaction (RT-PCR). Only serum samples with repeatedly detectable HBV DNA were considered positive. Patients were divided into 2 groups: HCV RNA positive and HCV RNA negative, based on the results of a third generation enzyme linked immunosorbent assay (ELISA) anti-HCV test and HCV RNA PCR.

Results

HBV DNA was detected in 6 of the 145 patients (4.1%) and HBcAb was detected in 29/145 patients (20%). There were no statistically significant differences in the age, duration of hemodialysis, biochemical parameters, serological markers of HBV, or HBV DNA between patients with and without HCV infection.

Conclusions

Four percent of the hemodialysis patients had OBI. There was no significant difference in the prevalence of OBI between hemodialysis patients with or without HCV co-infection.  相似文献   
1000.

Background

IL28B single nucleotide polymorphisms (SNPs) play important roles in the management of hepatitis C virus (HCV) infections and are strongly associated with spontaneous and treatment-induced HCV clearance.

Objectives

In the present study, the association between IL28B variants and the progression of HCV infection in Egyptian patients infected with type 4a virus will be examined.

Patients and Methods

Frequencies of the protective genotype C/C of SNP, rs12979860 were determined in healthy subjects, spontaneous resolvers, and chronic HCV type 4 patients with low F scores and in patients with end stage liver disease (ESLD). This study included a total of 404 subjects. Patients infected with HCV type 4a (n = 304) were divided into; chronic hepatitis C (CHC) with low F scores (CHC, n = 110), end stage liver disease (n = 110), liver cirrhosis (LC) (n = 35) and hepatocellular carcinoma (HCC) patients (n = 75), spontaneous resolvers of HCV infection (n = 84) were also included. A healthy group representing the Egyptian population (n = 100) was also included in the genotyping of IL28B. The later was typed via a polymerase chain reaction based restriction fragment length polymorphism (PCR-RFLP) assay analysis on purified genomic DNA extracted from all individuals.

Results

A significant increase (P < 0.0005) was observed in frequencies of IL-28B rs12979860 C/C genotypes in the healthy population, than in the CHC, LC and HCC groups (C/C = 48%, 13%, 0%.and 0% respectively). On the other hand the C/C genotype was significantly higher (P < 0.0005) in spontaneous resolvers than in healthy subjects. A comparable significant increase in the frequency of C/T allele accompanied by mild elevation of T/T allele frequency, were detected along the progression towards ESLD.

Conclusions

Genotype C/C is associated with viral clearance during acute infection. The sharp decline in the C/C genotype from healthy to CHC subjects and the total absence of the C/C genotype in ESLD suggests a central role of this genotype against HCV disease progression.  相似文献   
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