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Metabolic syndrome is a constellation of major risk factors for cardiovascular disease. In affected individuals with this syndrome, the independent contribution of low high-density lipoprotein-cholesterol and increased triglyceride levels to the development of atherosclerosis remains to be clarified. We assessed the relationship between these 2 parameters and several surrogate markers for atherosclerosis. One hundred and twenty overweight cases, defined as having high-density lipoprotein-cholesterol (or=75 percentile) were compared with 120 discordant overweight controls defined on lipid values (high-density lipoprotein-cholesterol >or=50 percentile and triglycerides 相似文献   
55.

BACKGROUND:

Optimal management of obscure gastrointestinal bleeding (OGIB) remains unclear.

OBJECTIVE:

To evaluate diagnostic yields and downstream clinical outcomes comparing video capsule endoscopy (VCE) with push enteroscopy (PE).

METHODS:

Patients with OGIB and negative esophagogastroduodenoscopies and colonoscopies were randomly assigned to VCE or PE and followed for 12 months. End points included diagnostic yield, acute or chronic bleeding, health resource utilization and crossovers.

RESULTS:

Data from 79 patients were analyzed (VCE n=40; PE n=39; 82.3% overt OGIB). VCE had greater diagnostic yield (72.5% versus 48.7%; P<0.05), especially in the distal small bowel (58% versus 13%; P<0.01). More VCE-identified lesions were rated possible or certain causes of bleeding (79.3% versus 35.0%; P<0.05). During follow-up, there were no differences in the rates of ongoing bleeding (acute [40.0% versus 38.5%; P not significant], chronic [32.5% versus 45.6%; P not significant]), nor in health resource utilization. Fewer VCE-first patients crossed over due to ongoing bleeding (22.5% versus 48.7%; P<0.05).

CONCLUSIONS:

A VCE-first approach had a significant diagnostic advantage over PE-first in patients with OGIB, especially with regard to detecting small bowel lesions, affecting clinical certainty and subsequent further small bowel investigations, with no subsequent differences in bleeding or resource utilization outcomes in follow-up. These findings question the clinical relevance of many of the discovered endoscopic lesions or the ability to treat most of these effectively over time. Improved prognostication of both patient characteristics and endoscopic lesion appearance with regard to bleeding behaviour, coupled with the impact of therapeutic deep enteroscopy, is now required using adapted, high-quality study methodologies.  相似文献   
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BackgroundPeripheral artery disease (PAD) screening may be performed to prevent progression of PAD or future cardiovascular disease in general. Recommendations for PAD screening have to be derived indirectly because no randomized trials comparing screening versus no screening have been performed. We performed a systematic review of guidelines to evaluate the value of PAD screening in asymptomatic adults.MethodsGuidelines in English published between January 1, 2003 and January 20, 2011 were retrieved using MEDLINE, CINAHL, the National Guideline Clearinghouse, the National Library for Health, the Canadian Medication Association Infobase, and the G-I-N International Guideline Library. Guidelines developed by national and international medical societies from Western countries, containing recommendations on PAD screening, were included. Two reviewers independently assessed rigor of guideline development using the Appraisal of Guidelines Research and Evaluation (AGREE) instrument. One reviewer performed full extraction of recommendations, which was validated by a second reviewer.ResultsOf 2779 titles identified, 8 guidelines were included. AGREE scores varied from 33% to 81%. Five guidelines advocated PAD screening, others found insufficient evidence for PAD screening or were against it. Measurement of the ankle-brachial index (ABI) was generally recommended for middle-aged populations with elevated cardiovascular risk levels. Those identified as having PAD are reclassified as high risk, warranting intensive preventive interventions to reduce their risk of a cardiovascular event. The underlying evidence mainly consisted of studies performed in patients with established PAD. A meta-analysis that evaluated ABI testing in the context of traditional cardiovascular risk assessment was interpreted differently.ConclusionsRecommendations on PAD screening vary across current guidelines, making the value of PAD screening uncertain. The variation seems to reflect lack of studies that show added value of detection of early PAD beyond expectant management and traditional risk assessment.  相似文献   
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Stress induces analgesia by mechanisms within and outside the brain. Here we show that the sympathetic nervous system is an essential trigger of intrinsic opioid analgesia within peripheral injured tissue. Noradrenaline, injected directly into inflamed hind paws of male Wistar rats, produced dose-dependent antinociception, reversible by alpha(1)-, alpha(2)- and beta(2)-antagonists. alpha(1)-, alpha(2)- and beta(2)-adrenergic receptors were demonstrated on beta-endorphin-containing immune cells and noradrenaline induced adrenergic receptor-specific release of beta-endorphin from immune cell suspensions. This antinociceptive effect of noradrenaline was reversed by micro - and delta-opioid antagonists as well as by anti-beta-endorphin. Stress-induced peripheral analgesia was abolished by chemical sympathectomy and by adrenergic antagonists. These findings indicate that sympathetic neuron-derived noradrenaline stimulates adrenergic receptors on inflammatory cells to release beta-endorphin, which induces analgesia via activation of peripheral opioid receptors.  相似文献   
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Adherence of the opportunistic fungus Aspergillus fumigatus to the extracellular matrix components is considered a crucial step in the establishment of the infection. Given the high carbohydrate content of these glycoproteins and the role of carbohydrate-protein interactions in numerous adherence processes, the presence of a lectin in A. fumigatus was investigated. Different fungal extracts obtained by sonication or grinding in liquid nitrogen from resting or swollen conidia, as well as from germ tubes and mycelium, were tested by hemagglutination assays using rabbit erythrocytes. A lectin activity was recovered in all the extracts tested. However, sonication of resting conidia resulted in the highest specific activity. Purification of the lectin was achieved by gel filtration followed by ion-exchange and hydrophobic-interaction chromatographies. Analysis of the purified lectin by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed an apparent molecular mass of 32 kDa, which is similar to that of the alkaline protease already identified from different strains of A. fumigatus. However, as evidenced by the use of an alkaline protease-deficient mutant, the two activities were supported by distinct proteins. In addition, hemagglutination inhibition experiments using different saccharides and glycoproteins demonstrated the specificity of the lectin for sialic acid residues. Together these results suggest that this lectin may contribute to the attachment of conidia to the extracellular matrix components through the recognition of the numerous terminal sialic acid residues of their carbohydrate chains.  相似文献   
60.
HCV is usually transmitted via the blood, but HCV RNA has been detected recently in seminal fluid. This study was done to study HCV seminal shedding and factors that could influence the presence of HCV in the seminal fluid of men coinfected with HCV and HIV-1. HCV and HIV-1 genomes were assayed in multiple paired blood and semen samples obtained from 35 men enrolled in an assisted medical procreation protocol. HCV RNA was found intermittently in semen samples from 9 patients (25.7%). Samples from 9 men with HCV RNA in their semen and 26 men without were compared to further analyze these parameters. No correlation was found between HCV RNA in the seminal fluid and age, HCV virus load, the duration of HIV-1 infection, HIV treatment, the CD4(+) cell count, HIV-1 virus load or HIV-1 detection in the semen. The intermittent detection of HCV RNA in semen samples support the systematic search for HCV RNA in semen and the use of processed spermatozoa in assisted medical procreation of infertile HCV serodiscordant couples.  相似文献   
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