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91.
AimsBariatric surgery (BS) is recommended for subjects with a Body Mass Index (BMI) over of 40 kg/m2 or with a BMI between 35 and 40 kg/m2 with obesity-related comorbidities. Aim of the study was to compare different types of BS with medical therapy (MT) for the treatment of obesity.Data synthesisWe conducted a network-meta-analysis (NMA) including randomized clinical trials comparing different BS techniques versus MT in people with obesity, with a duration ≥24 weeks (PROSPERO, #CRD42020160359). Primary endpoint was BMI. Indirect comparisons of different types of surgery were performed by NMA. Types of BS included: laparoscopic adjustable gastric banding (LAGB), Roux-en-Y gastric bypass, sleeve gastrectomy (SG), bilio-pancreatic diversion (BPD); greater curvature plication (GCP); one-anastomosis gastric bypass (OAGB); Laparoscopic Vertical Banded Gastroplasty (LVBG) and duodenal switch (DS). 43 trials were retrieved in this metanalysis. BS was associated with a significant reduction in BMI, systolic blood pressure, triglyceride and fasting glucose, and with a significant increase of HDL cholesterol when compared to MT. In direct comparisons, RYGB was more effective than LAGB, LVBG, and GCP, but less effective than DS, whereas LAGB was less effective than LVBG and SG. In the NMA, DS and BPD appeared to be more effective than other procedures.ConclusionsBS produces a greater weight loss than MT in morbidly obese patients, inducing a greater improvement of obesity-associated metabolic parameters. Available data are insufficient to assess the effect of BS on mortality. Different surgical procedures are heterogeneous for efficacy and safety.  相似文献   
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93.
BackgroundPatients with out-of-hospital cardiac arrest (OHCA) due to acute coronary syndromes (ACS) who undergo percutaneous coronary intervention (PCI) are at high risk of bleeding and thrombosis. While predictive bleeding and stent thrombosis risk scores have been established, their performance in patients with OHCA has not been evaluated.MethodsAll consecutive patients admitted for OHCA due to ACS who underwent PCI between January 2007 and December 2019 were included. The ACTION and CRUSADE bleeding risk scores and the Dangas score for early stent thrombosis risk were calculated for each patient. A C-statistic analysis was performed to assess the performance of these scores.ResultsAmong 386 included patients, 82 patients (21.2%) experienced severe bleeding and 30 patients (7.8%) experienced stent thrombosis. The predictive performance of the ACTION and CRUSADE bleeding risk scores for major bleeding was poor, with areas under the curve (AUCs) of 0.596 and 0.548, respectively. Likewise, the predictive performance of the Dangas stent thrombosis risk score was poor (AUC 0.513). Using multivariable analysis, prolonged low-flow (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.00–1.05; P = 0.025), reduced haematocrit or fibrinogen at admission (OR 0.93, 95% CI 0.88–0.98; P = 0.010 and OR 0.61; 95% CI 0.41–0.89; P = 0.012, respectively) and the use of glycoprotein IIb/IIIa inhibitors (OR 2.10, 95% CI 1.18–3.73; P = 0.011) were independent risk factors for major bleeding.ConclusionThe classic bleeding and stent thrombosis risk scores have poor performance in a population of patients with ACS complicated by OHCA. Other predictive factors might be more pertinent to determine major bleeding and stent thrombosis risks in this specific population.  相似文献   
94.
AimsTo identify the geometrical alterations in the age-remodeled rat coronary artery network and to develop a useful technique to analyze network properties in the rat heart.Methods and resultsWe analyzed the networks of the left anterior descendent coronary arteries on in situ perfused hearts of young (3 months) and old (18 months) male rats. All segments and branching over >80 μm diameter were analyzed using 50 μm long cylindrical ring units of the networks. Arterial widening and paucity, increased tortuosity were typical features in the old network. In addition, axis angles deviated more from the mother branches in the old, whereas the diameters of daughter branches fit the Murray law in both groups. The detected changes in the old network resulted in a longer blood flow route for the same direct distance.ConclusionWe developed a useful method to investigate arterial network property changes in the rat heart. Ageing resulted in longer, more tortuous flow route in the LAD network that might be hemodynamically disadvantageous.  相似文献   
95.
《Autoimmunity》2013,46(4):320-331
Circulating autoantibodies to beta cell antigens are present in the majority of patients with Type 1 diabetes. These autoantibodies can be detected before and at time of clinical diagnosis of disease. Although the role of autoantibodies in the pathogenesis of the disease is debated, their presence indicates a dysregulation of the humoral immune response. Mechanisms regulating autoantibodies in Type 1 diabetes are not well understood. In contrast, in other autoimmune diseases there is acceptance that autoantibodies are regulated not only by antigen but also by other antibodies that bind to the antigen-binding site of these autoantibodies (anti-idiotypic antibodies). The proposed purpose of this network is to maintain an equilibrium between autoantibodies and their anti-idiotypic antibodies, preventing autoimmunity, while allowing a robust response to exogenous antigen. Anti-idiotypic antibodies regulate both autoantibody binding and their levels by a) neutralizing autoantibodies, and b) inhibiting the secretion of autoantibodies. Because it has been proposed that the B lymphocytes that produce autoantibodies function as autoantigen presenting cells, inhibiting their binding to autoantigen by anti-idiotypic antibodies may prevent development of autoimmune disease. This hypothesis is supported by the presence of anti-idiotypic antibodies in healthy individuals and in patients in remission from autoimmune diseases, and by the lack of anti-idiotypic antibodies during active disease. We recently reported the presence of autoantibodies to glutamate decarboxylase in the majority of healthy individuals, where their binding to autoantigen is prevented by anti-idiotypic antibodies. These anti-idiotypic antibodies are absent at clinical diagnosis of Type 1 diabetes, revealing the presence of autoantibodies. Type 1 diabetes (T1D) is an autoimmune disease characterized by the dysfunction and destruction of insulin-producing beta cells by autoreactive T cells. Although much progress has been made towards understanding the respective roles of effector and regulatory T cells in this beta cell destruction, the development of autoantibodies to beta cell proteins is widely considered simply a by-product of the autoimmune destruction of the beta cells, rather than having an active role in the pathogenesis. This view is starting to change based on increasing recognition that autoantibodies can have defined roles in other autoimmune diseases, and the emergence of new data on their role in T1D. This exploration of the role of autoantibodies in autoimmune disease has been spurred, in part, by increasing recognition that development of autoimmune diseases is influenced by regulatory antibodies (anti-idiotypic antibodies) directed against the unique binding site of autoantibodies. This review provides an overview of the development and function of these anti-idiotypic antibodies, and present evidence supporting their role in the development of autoimmune diseases. Finally, we conclude this review with a model of the events that may cause loss of anti-idiotypic antibodies and the implications for the development of T1D.  相似文献   
96.
Trauma can produce posttraumatic stress disorder (PTSD), but may also foster positive outcomes, such as posttraumatic growth. Individual differences in coping styles may contribute to both positive and negative sequelae of trauma. Using network analytic methods, we investigated the structure of PTSD symptoms, elements of growth, and coping styles in bereaved survivors of a major earthquake in China. Hypervigilance and difficulty concentrating were identified as the most central symptoms in the PTSD network, whereas establishing a new path in life, feeling closer to others, and doing better things with life ranked highest on centrality in the posttraumatic growth network. Direct connections between PTSD symptoms and elements of growth were low in magnitude in our sample. Our final network, which included PTSD symptoms, growth elements, and coping styles, suggests that adaptive and active coping styles, such as positive reframing, are positively related to elements of growth, but not appreciably negatively related to PTSD symptoms. Conversely, maladaptive coping styles are positively related to PTSD symptoms, but are not negatively associated with growth. Future longitudinal studies could shed light on the direction of causality in these relationships and their clinical utility.  相似文献   
97.
Two prominent conceptual models of posttraumatic stress disorder (PTSD) are the cognitive model, associated with cognitive processing therapy (CPT; Resick & Schnicke, 1992), and the functional contextualist model, underlying acceptance and commitment therapy (ACT; Hayes et al., 1999). Network analysis was used to examine dynamic interactions among cognitive (relating to CPT) and functional contextualistic (relating to ACT) variables and PTSD symptoms in a sample of 722 trauma-exposed adults. Results from the cognitive networks highlighted the importance of maladaptive beliefs about threat in maintaining the co-occurrence of PTSD symptoms and cognitive variables. Additionally, PTSD symptoms were more likely to lead to cognitive variables, rather than the reverse direction. Results from the functional contextualist networks identified numerous associations amongst variables that contribute to the co-occurrence of PTSD symptoms and psychological inflexibility. Findings from this study may help generate causal hypotheses that can be tested further using a longitudinal study design.  相似文献   
98.
BackgroundThere has been increasing interest in classifying inflammatory phenotypes of depression. Most investigations into inflammatory phenotypes only have tested whether elevated inflammation is associated with elevated levels of depression symptoms, or risk for a diagnosis. This study expanded the definition of phenotype to include the structure of depression symptoms as a function of inflammation.MethodsNetwork models of depression symptoms were estimated in a sample of 4157 adults (mean age = 47.6, 51% female) from the 2015–2016 National Health and Nutrition Examination Survey (NHANES). Analyses included comparisons of networks between those with elevated (C-reactive protein (CRP) values ≥ 3.0 mg/L; N = 1696) and non-elevated CRP (N = 2841) as well as moderated network models with CRP group status and raw CRP values moderating the associations between depression symptoms.ResultsDifferences emerged at all levels of analysis (global, symptom-specific, symptom—symptom associations). Specifically, the elevated CRP group had greater symptom connectivity (stronger total associations between symptoms). Further, difficulty concentrating and psychomotor difficulties had higher expected influence (concordance with other symptoms) in the elevated CRP group. Finally, there was evidence that several symptom—symptom associations were moderated by CRP. Conclusions: This study provides consistent evidence that the structure of depression symptoms varies as a function of CRP levels. Greater symptom connectivity might contribute to why elevated CRP is associated with treatment-resistant depression. Additionally, differences in symptom structure might highlight different maintenance mechanisms and treatment targets for individuals with compared to those without elevated CRP. Finally, differences in symptom structure as a function of CRP highlight a potential misalignment of standard depression measures (the structure of which are evaluated on groups unselected for CRP levels) and the presentation of depression symptoms in those with elevated CRP.  相似文献   
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100.
目的 以网络药理学技术探讨趋化因子-13(CXCL-13)对人骨髓间充质干细胞(BMSCs)增殖和迁移的影响。 方法 在线数据库预测CXCL-13作用于BMSCs的靶点。Metascape数据库对靶点的基因本体论和京都基因与基因组百科全书(KEGG)信号通路进行富集分析。STRING 11.0数据库进行蛋白质相互作用分析,Cytoscape 3.8的cytoHubba 0.1插件筛选核心基因编码的蛋白质。BMSCs分为对照组、CXCL-13组和PI3K抑制剂组。分别以MTT、流式细胞术和Transwell细胞小室迁移实验检测各组BMSCs的吸光度(A)值、细胞凋亡率和细胞迁移数目情况;ELISA检测各组BMSCs上清液表皮生长因子(EGF)和血管内皮生长因子(VEGF)蛋白含量。Western blotting检测各组BMSCs的Akt、磷酸化Akt(p-Akt)蛋白的表达。 结果 CXCL-13作用于BMSCs 21个靶点。与细胞增殖相关的生物学过程包括干细胞增殖、调节内皮细胞增殖、正向调控平滑肌细胞增殖等32条;与细胞迁移相关的生物学过程包括调节细胞迁移、阿米巴状细胞迁移、调节内皮细胞迁移等22条。KEGG通路包括癌症途径、PI3K-Akt信号通路、MAPK信号通路等40条。核心蛋白包括肿瘤蛋白P53(TP53)、表皮生长因子受体(EGFR)、90kD热休克蛋白αB1(HSP90AB1)、蛋白激酶Cα(PRKCA)、雌激素受体2(ESR2)及前列腺素E受体4(PTGER4)。与其他组相比,CXCL-13组BMSCs的吸光度(A)值和细胞迁移数目均显著增高(P<0.01,n=15),细胞凋亡率明显降低(P<0.01,n=15);PI3K抑制剂组BMSCs的A值、细胞凋亡率和细胞迁移数目与CXCL-13组相比均呈相反变化(P<0.01,n=15)。相对于对照组,CXCL-13组BMSCs的EGF和VEGF蛋白含量显著提高(P<0.01,n=15),Akt和p-Akt相对表达均明显升高(P<0.01,n=9);而PI3K抑制剂组EGF和VEGF蛋白含量、Akt和p-Akt相对表达呈相反变化。 结论 CXCL-13激活PI3K-Akt通路促进BMSCs旁分泌EGF和VEGF蛋白,提高BMSCs增殖和迁移,抑制BMSCs凋亡。  相似文献   
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