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991.
Genetic polymorphisms near IL28B are associated with spontaneous and treatment-induced clearance of hepatitis C virus (HCV), two processes that require the appropriate activation of the host immune responses. Intrahepatic inflammation is believed to mirror such activation, but its relationship with IL28B polymorphisms has yet to be fully appreciated. We analyzed the association of IL28B polymorphisms with histological and follow-up features in 2335 chronically HCV-infected Caucasian patients. Assessable phenotypes before any antiviral treatment included necroinflammatory activity (n = 1,098), fibrosis (n = 1,527), fibrosis progression rate (n = 1,312), and hepatocellular carcinoma development (n = 1,915). Associations of alleles with the phenotypes were evaluated by univariate analysis and multivariate logistic regression, accounting for all relevant covariates. The rare G allele at IL28B marker rs8099917-previously shown to be at risk of treatment failure-was associated with lower activity (P = 0.04), lower fibrosis (P = 0.02) with a trend toward lower fibrosis progression rate (P = 0.06). When stratified according to HCV genotype, most significant associations were observed in patients infected with non-1 genotypes (P = 0.003 for activity, P = 0.001 for fibrosis, and P = 0.02 for fibrosis progression rate), where the odds ratio of having necroinflammation or rapid fibrosis progression for patients with IL28B genotypes TG or GG versus TT were 0.48 (95% confidence intervals 0.30-0.78) and 0.56 (0.35-0.92), respectively. IL28B polymorphisms were not predictive of the development of hepatocellular carcinoma. CONCLUSION: In chronic hepatitis C, IL28B variants associated with poor response to interferon therapy may predict slower fibrosis progression, especially in patients infected with non-1 HCV genotypes.  相似文献   
992.
993.
994.
Allergic bronchopulmonary aspergillosis (ABPA) is caused by an exaggerated T(H)2 response to the ubiquitous mold Aspergillus fumigatus. ABPA develops in a small fraction of patients with cystic fibrosis and asthma, suggesting that intrinsic host defects play a major role in disease susceptibility. This article reviews current understanding of the immunopathology, clinical and laboratory findings, and diagnosis and management of ABPA. It highlights clinical and laboratory clues to differentiate ABPA from cystic fibrosis and asthma, which are challenging given clinical and serologic similarities. A practical diagnostic algorithm and management scheme to aid in the treatment of these patients is outlined.  相似文献   
995.
The term phenotype in the field of COPD is defined as "a single or combination of disease attributes that describe differences between individuals with COPD as they relate to clinically meaningful outcomes". Among all phenotypes described, there are three that are associated with prognosis and especially are associated with a different response to currently available therapies. There phenotypes are: the exacerbator, the overlap COPD-asthma and the emphysema-hyperinflation. The exacerbator is characterised by the presence of, at least, two exacerbations the previous year, and on top of long-acting bronchodilators, may require the use of antiinflammatory drugs. The overlap phenotype presents symptoms of increased variability of airflow and incompletely reversible airflow obstruction. Due to the underlying inflammatory profile, it uses to have a good therapeutic response to inhaled corticosteroids in addition to bronchodilators. Lastly, the emphysema phenotype presents a poor therapeutic response to the existing antiinflammatory drugs and long-acting bronchodilators together with rehabilitation are the treatments of choice. Identifying the peculiarities of the different phenotypes of COPD will allow us to implement a more personalised treatment, in which the characteristics of the patients, together with their severity will be key to choose the best treatment option.  相似文献   
996.

Introduction

Although asthma and COPD are different pathologies, many patients share characteristics from both entities. These cases can have different evolutions and responses to treatment. Nevertheless, the evidence available is limited, and it is necessary to evaluate whether they represent a differential phenotype and provide recommendations about diagnosis and treatment, in addition to identifying possible gaps in our understanding of asthma and COPD.

Methods

A nation-wide consensus of experts in COPD in two stages: 1) during an initial meeting, the topics to be dealt with were established and a first draft of statements was elaborated with a structured «brainstorming» method; 2) consensus was reached with two rounds of e-mails, using a Likert-type scale.

Results

Consensus was reached about the existence of a differential clinical phenotype known as «Overlap Phenotype COPD-Asthma», whose diagnosis is made when 2 major criteria and 2 minor criteria are met. The major criteria include very positive bronchodilator test (increase in FEV1 ≥ 15% and ≥ 400 ml), eosinophilia in sputum and personal history of asthma. Minor criteria include high total IgE, personal history of atopy and positive bronchodilator test (increase in FEV1 ≥ 12% and ≥ 200 ml) on two or more occasions. The early use of individually-adjusted inhaled corticosteroids is recommended, and caution must be taken with their abrupt withdrawal. Meanwhile, in severe cases the use of triple therapy should be evaluated. Finally, there is an obvious lack of specific studies about the natural history and the treatment of these patients.

Conclusions

It is necessary to expand our knowledge about this phenotype in order to establish adequate guidelines and recommendations for its diagnosis and treatment.  相似文献   
997.
Increased afterload results in ‘pathological’ cardiac hypertrophy, the most important risk factor for the development of heart failure. Current in vitro models fall short in deciphering the mechanisms of hypertrophy induced by afterload enhancement. The aim of this study was to develop an experimental model that allows investigating the impact of afterload enhancement (AE) on work-performing heart muscles in vitro. Fibrin-based engineered heart tissue (EHT) was cast between two hollow elastic silicone posts in a 24-well cell culture format. After 2?weeks, the posts were reinforced with metal braces, which markedly increased afterload of the spontaneously beating EHTs. Serum-free, triiodothyronine-, and hydrocortisone-supplemented medium conditions were established to prevent undefined serum effects. Control EHTs were handled identically without reinforcement. Endothelin-1 (ET-1)- or phenylephrine (PE)-stimulated EHTs served as positive control for hypertrophy. Cardiomyocytes in EHTs enlarged by 28.4?% under AE and to a similar extent by ET-1- or PE-stimulation (40.6 or 23.6?%), as determined by dystrophin staining. Cardiomyocyte hypertrophy was accompanied by activation of the fetal gene program, increased glucose consumption, and increased mRNA levels and extracellular deposition of collagen-1. Importantly, afterload-enhanced EHTs exhibited reduced contractile force and impaired diastolic relaxation directly after release of the metal braces. These deleterious effects of afterload enhancement were preventable by endothelin-A, but not endothelin-B receptor blockade. Sustained afterload enhancement of EHTs alone is sufficient to induce pathological cardiac remodeling with reduced contractile function and increased glucose consumption. The model will be useful to investigate novel therapeutic approaches in a simple and fast manner.  相似文献   
998.
Although rare, coronary artery stent infections are associated with a high mortality rate. Since the introduction of coronary stents in 1987, only 16 cases of infection have been reported. We report a new case in a 66-year-old woman who had undergone a difficult percutaneous coronary intervention procedure, during which 3 overlapping stents were implanted in the mid portion of the right coronary artery. Twenty-two days after the procedure, the patient died. Autopsy revealed the cause of death to be pericardial tamponade due to rupture of the right ventricular myocardium. The stented portion of the right coronary artery was enveloped by an abscess, and purulent material completely occluded the stents. Cultures of the myocardium were positive for methicillin-resistant Staphylococcus aureus. We conducted a review of the literature on coronary artery stent infections. Data suggest that early-onset infections (<10 days after stent implantation) are potentially amenable to medical therapy alone, but late-onset infections (≥10 days after implantation) or major complications necessitate combined surgical and medical therapy. Medical therapy consists of broad-spectrum antibiotics. Surgical intervention includes stent removal if possible, and abscess drainage or perforation repair when indicated.Key words: Blood vessel prosthesis implantation/adverse effects, coronary stent infections, prosthesis-related infections/complications/diagnosis/therapy, stents/adverse effects, Staphylococcus aureusCoronary artery stents have been in use for more than 2 decades. Stent infections are rare, hard to treat, and potentially devastating. Our treatment of a patient with a coronary stent abscess prompted us to review the literature. From our experience and the evaluation of previously reported cases,1–14 we propose an approach for diagnosing and treating these infections.  相似文献   
999.
Colorectal cancer rarely metastasizes to the heart. In the world medical literature, we identified only 7 cases of well-documented colorectal cancer metastasis to the right atrium. Herein, we describe the case of a 72-year-old man in whom metastatic mucinous adenocarcinoma of the colon involved the right atrium and caused superior vena cava syndrome. To our knowledge, this is the first case report of sudden cardiac death due to embolization of metastatic colon cancer from the right atrium. We also present the first comprehensive case series review of this rare entity.Given improvements in diagnostic and therapeutic methods that have increased the longevity of many cancer patients, the detection of cardiac metastases is likely to increase in frequency. Accordingly, we recommend that previously asymptomatic cancer patients with a history of colorectal cancer who develop cardiac symptoms undergo prompt investigation for possible cardiac metastasis.  相似文献   
1000.
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