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In recent years,a number of case reports and clinical studies have highlighted the risk of hepatitis B and C virus reactivation in patients with inflammatory bowel disease who are treated with immunosuppressive drugs.The cases of viral hepatitis reactivation that have been reported are characterized by a wide range of clinical manifestations,from viremia without clinically relevant manifestations to fulminant life-threatening hepatitis.The development and dissemination of biological immunosuppressive drugs have led to a significant increase in the number of reports of interest to physicians in a variety of clinical settings.On this topic,there have been a number of published guidelines and reviews that have collected the available evidence,providing recommendations on prophylactic and therapeutic strategies and methods for monitoring patients at risk.However,it should be noted that,to date,very few clinical studies have been published,and most of the recommendations have been borrowed from otherclinical settings.The published studies are mostly retrospective and are based on very heterogeneous populations,using different therapeutic and prophylactic regimens and obtaining conflicting results.Thus,it seems clear that it is desirable to concentrate our efforts on prospective studies,not conducting further reviews of the literature in the continued absence of new evidence.  相似文献   
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No data are present in the literature about the effect of cytokines on the prototype β chemokine (C-C motif) ligand 2 (CCL2) or of peroxisome proliferator-activated receptor α (PPARα (PPARA)) activation on CCL2 and CXCL10 chemokines secretion in fibroblasts or preadipocytes in Graves' ophthalmopathy (GO). We have tested the effect of interferon γ (IFNγ (IFNG)) and tumor necrosis factor α (TNFα) on CCL2, and for comparison on the prototype α chemokine (C-X-C motif) ligand 10 (CXCL10), and the possible modulatory role of PPARα activation on secretion of these chemokines in normal and GO fibroblasts or preadipocytes in primary cell cultures. This study shows that IFNγ alone, or in combination with TNFα, stimulates the secretion of CCL2 in primary orbital fibroblasts or preadipocytes from patients with GO at levels similar to those observed in controls. IFNγ and TNFα also stimulated CXCL10 chemokine secretion as expected. The presence of PPARα and PPARγ (PPARG) in primary fibroblasts or preadipocytes of patients with GO has been confirmed. PPARα activators were able to inhibit the secretion of CXCL10 and CCL2, while PPARγ activators were confirmed to be able to inhibit CXCL10 but had no effect on CCL2. PPARα activators were stronger inhibitors of chemokine secretions than PPARγ agonists. In conclusion, CCL2 and CXCL10 are modulated by IFNγ and TNFα in GO. PPARα activators inhibit the secretion of the main prototype α (CXCL10) and β (CCL2) chemokines in GO fibroblasts or preadipocytes, suggesting that PPARα may be involved in the modulation of the immune response in GO.  相似文献   
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ObjectiveThe objective was to evaluate the seasonal lipid variations in type 2 diabetic (DM2) outpatients.Materials/Methods302 (183 women and 119 men) DM2 subjects with or without statins therapy were screened. Body weight, HbA1c, total cholesterol (TC), high density lipoprotein (HDL-C), triglycerides (Trg) and low density lipoprotein cholesterol (LDL-C) were measured and patients’ data of diet and physical activity were recorded during fall/winter (F/W) and spring/summer (S/S) seasons.ResultsHbA1c levels showed seasonal variability without statistical significance. During the colder seasons we observed an increase (P<.05) of weight associated with higher calorie intake and reduced physical activity. We showed a peak of TC, LDL-C and Trg levels during F/W while HDL-C levels were reduced. Median TC levels in F/W with respect to S/S were 197 vs 185 mg/dL (P<.001) without statins therapy and 172 vs 161 mg/dL (P<.001) in patients under statins therapy. Median LDL-C levels, without or with statin therapy, were 122 vs 114 mg/dL (P<.001) and 97.5 vs 88.5 mg/dL (P<.001), respectively. This seasonal lipids changes from F/W to S/S, modulated the percent of patients at LDL-C target < 100 mg/dL, both without or under statins treatment: from 22% to 29.5% (P<.05) with odds ratio 0.73 (95% CI 0.62–0.87) and from 47% to 55% (P<.001) with odds ratio 0.68 (95% CI 0.58–0.76), respectively.ConclusionsDM2 patients showed a peak of TC and LDL-C during colder months associated with changes of diet and lifestyle habits. This seasonal lipid trend modified the percentage of patients at LDL-C therapeutical target.  相似文献   
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The transition from the Middle Stone Age (MSA) to the Later Stone Age (LSA) in South Africa was not associated with the appearance of anatomically modern humans and the extinction of Neandertals, as in the Middle to Upper Paleolithic transition in Western Europe. It has therefore attracted less attention, yet it provides insights into patterns of technological evolution not associated with a new hominin. Data from Border Cave (KwaZulu-Natal) show a strong pattern of technological change at approximately 44-42 ka cal BP, marked by adoption of techniques and materials that were present but scarcely used in the previous MSA, and some novelties. The agent of change was neither a revolution nor the advent of a new species of human. Although most evident in personal ornaments and symbolic markings, the change from one way of living to another was not restricted to aesthetics. Our analysis shows that: (i) at Border Cave two assemblages, dated to 45-49 and >49 ka, show a gradual abandonment of the technology and tool types of the post-Howiesons Poort period and can be considered transitional industries; (ii) the 44-42 ka cal BP assemblages are based on an expedient technology dominated by bipolar knapping, with microliths hafted with pitch from Podocarpus bark, worked suid tusks, ostrich eggshell beads, bone arrowheads, engraved bones, bored stones, and digging sticks; (iii) these assemblages mark the beginning of the LSA in South Africa; (iv) the LSA emerged by internal evolution; and (v) the process of change began sometime after 56 ka.  相似文献   
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The aim of this study was to assess exercise test results and efficacy of therapy with a β blocker (acebutolol) in ryanodine receptor type 2 (RyR2) mutation carriers with documented ventricular arrhythmias (VAs) and long-term follow-up. Twenty RyR2 mutation carriers belonging to 8 families and regularly followed at our center were analyzed using a study protocol involving electrocardiography, exercise tests off and on β-blocker therapy, 2-dimensional echocardiography, and signal-averaged electrocardiography. Off-therapy exercise testing triggered the onset of VAs at different heart rates (mean 132 ± 13 beats/min) with various patterns that worsened while exercising and disappeared immediately after stopping. The most severe VAs detected were nonsustained ventricular tachycardia in 35% and ventricular couplets in 35%. In the remaining subjects single ventricular premature beats were recorded. In 15% of patients single monomorphic ventricular premature beats were detected and identified to be linked to RyR2 mutations owing to the presence of sudden deaths of their family members and subsequent family screening. Acebutolol made the VAs disappear completely in 20% of subjects and decreased their complexity in 50%, whereas it did not change VAs appreciably in 30% of patients with less complex VAs. After 11 ± 8 years of follow-up 2 patients developed syncope. In conclusion, exercise testing was a fundamental tool for assessing the clinical phenotype and efficacy of therapy in RyR2 mutation carriers and therapy with acebutolol led in most subjects to a decreased complexity of the arrhythmic pattern or to complete suppression.  相似文献   
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