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51.
52.

Background and objectives

Previous research suggests that negative interpretation biases stimulate anxiety. As patients with an anxiety disorder tend to interpret ambiguous information negatively, it was hypothesised that training more positive interpretations reduces negative interpretation biases and emotional problems.

Methods

In a randomised, double-blind placebo-controlled trial, patients with different anxiety disorders were trained online over eight days to either generate positive interpretations of ambiguous social scenarios (n = 18) or to generate 50% positive and 50% negative interpretations in the placebo control condition (n = 18) (Study 1).

Results

Positively trained patients made more positive interpretations and less negative ones than control patients. This training was followed by a decrease in anxiety, depression, and general psychological distress, but this effect was also observed in the control group. To get a better understanding of these unexpected results, we tested a 100% neutral placebo control group (Study 2, n = 19); now the scenarios described neutral, non-emotional situations and no valenced interpretations were generated. The results from this neutral group were comparable to the effects from the other control group.

Limitations

An advantage, but potentially also a disadvantage of the study is that CBM-I training was performed online with less control over the procedures and setting. In addition, the scenarios were not matched to the specific concerns of each patient and the training sessions were performed in close proximity to one another.

Conclusions

Compared to both control conditions, CBM-I had superior effects on interpretations, but not on emotions. The current findings showed the boundary conditions for CBM-I.  相似文献   
53.
腹腔注射链脲佐菌素建立糖尿病大鼠模型(DM组),结果显示糖尿病大鼠2周时氧化低密度脂蛋白(oxLDL)水平已高于正常对照大鼠[(2.87±0.40对2.27±0.36)μg/dl,P<0.05],血管舒张反应迟钝;6周时oxLDL水平更高[(4.32 ±0.66) μg/dl,P<0.01],乙酰胆碱诱导的血管环舒张最大百分比(Rmax)明显降低(P<0.01),糖尿病大鼠主动脉植物血凝素样氧化低密度脂蛋白受体1( LOX-1)、NF-kB、内皮细胞间黏附分子1(ICAM-1)蛋白及mRNA表达明显高于正常对照大鼠(P<0.01),糖尿病大鼠LOX-1 mRNA表达水平与外周血oxLDL水平、NF-kBp65、ICAM-1 mRNA表达水平正相关,与Rmax呈负相关.提示OxLDL/LOX-1系统可能通过激活NF-kB,上调ICAM-1的表达,导致糖尿病早期内皮功能障碍.  相似文献   
54.
目的通过体外细胞实验阐明丹参酮ⅡA对泡沫细胞胆固醇平衡的影响。方法体外培养小鼠RAW264.7细胞,以氧化型低密度脂蛋白诱导为泡沫细胞模型,并用不同浓度的丹参酮ⅡA进行处理,通过油红O染色观察细胞内脂质堆积情况,酶比色法定量检测细胞内总胆固醇和胆固醇酯的变化,荧光定量PCR和WesternBlot检测细胞中CD36、三磷酸腺苷结合盒转运体A1(ABCA1)、肝脏X受体α(LXRα)、过氧化体增殖物激活型受体α(PPARα)及PPARγ的mRNA和蛋白表达。结果 0~20 mg/L的丹参酮ⅡA对泡沫细胞增殖活力无明显影响,20 mg/L丹参酮ⅡA干预后,泡沫细胞内胆固醇酯与总胆固醇的比值显著降低,细胞内脂质累积减少,并上调AB-CA1、LXRα和PPARα的mRNA和蛋白表达,但对CD36表达无明显作用。结论丹参酮ⅡA能抑制泡沫细胞的形成,其机制可能是通过诱导PPARα、LXRα和ABCA1表达,促进胆固醇的外排。  相似文献   
55.
目的在动脉粥样硬化模型鼠中,观察达肝素对肾动脉粥样硬化病变进展及对植物血凝素样氧化型低密度脂蛋白受体1(LOX-1)和血管内皮生长因子(VEGF)的表达影响,探讨达肝素可能的抗动脉粥样硬化机制。方法以6周龄雄性C57BL/6J小鼠24只为对照,随机分为普通饲料组及高脂饲料组。雄性6周龄载脂蛋白E基因缺陷(Apo E-/-)小鼠36只,均予高脂饲料喂养至12周龄,随机分为模型组、低剂量肝素组[达肝素钠100 IU/(kg.d)]、高剂量肝素组[达肝素钠200 IU/(kg.d)],皮下注射连续4周(16周龄)后各组随机取6只处死。分离肾动脉,制成石蜡切片行HE及免疫组织化学染色,观察斑块情况及LOX-1蛋白的表达。用RT-PCR方法,检测肾动脉LOX-1 mRNA及VEGF mRNA的表达。用Western Blot分析法,检测肾动脉中LOX-1蛋白的表达。剩余小鼠继续原方案喂养4周(20周龄)后处死,肾动脉石蜡切片行HE染色,观察斑块情况。结果 Apo E-/-模型组在16周龄时出现轻度肾动脉粥样硬化。低剂量及高剂量达肝素均抑制肾动脉粥样硬化的形成(P<0.05)。Apo E-/-模型组LOX-1 mRNA、VEGF mRNA及LOX-1蛋白的表达水平较C57BL/6J普通饲料组的表达水平明显升高(P<0.05)。低剂量及高剂量达肝素治疗后,LOX-1 mRNA、VEGF mRNA及LOX-1蛋白的表达水平表达较模型组明显下降(P<0.05)。结论达肝素钠可能通过抑制LOX-1蛋白及VEGF表达的途径,抑制肾动脉粥样硬化的进展。  相似文献   
56.

Introduction

Medically ill, hospitalized patients are at increased risk for venous thromboembolism (VTE) after discharge. This study aimed to examine thromboprophylaxis patterns, risk factors, and post-discharge outcomes.

Methods

This was a retrospective claims analysis involving administrative claims data and in-patient data abstracted from a sample of hospital charts. Patients aged ≥ 40 years hospitalized for ≥ 2 days for nonsurgical reasons between 2005 and 2009 were included. Hospital chart data were abstracted for a random sample of patients without evidence of anticoagulant use at 30 days post-discharge. The combined data determined whether in-patient thromboprophylaxis (anticoagulant or mechanical prophylaxis) reduces risk of VTE at 90 days post-discharge. Hazard ratios (HR) and odds ratios (OR) were calculated using Cox proportional hazard models and logistic regression.

Results

Of 141,628 patients in the claims analysis, 3.9% received anticoagulants (3.6% warfarin). VTE, rehospitalization, and mortality rates were 1.9%, 17.2%, and 6.2%, respectively. The strongest predictors of post-discharge VTE were history of VTE (HR = 4.0, 95% confidence interval [CI]: 3.3-4.8), and rehospitalization (HR = 3.9, 95% CI: 3.6-4.3). Of 504 medical charts, 209 (41.5%) reported in-patient thromboprophylaxis. There was no statistically significant difference in post-discharge VTE rates between patients who did and did not receive in-patient thromboprophylaxis. All-cause mortality was greater among patients without use of VTE prophylaxis.

Conclusion

Utilization rates of in-hospital and post-discharge VTE prophylaxis were low. In-hospital VTE prophylaxis did not reduce the risk of post-discharge VTE in the absence of post-discharge anticoagulation. Combined in-patient and post-discharge thromboprophylaxis lowered the odds of short-term, all-cause post-discharge mortality.  相似文献   
57.
Objective PERK/eI F2α/CHOP is a major signaling pathway mediating endoplasmic reticulum(ER) stress related with atherosclerosis.Oxidized LDL(ox-LDL) also induces endothelial apoptosis and plays a vital role in the initiation and progression of atherosclerosis.The present study was conducted to explore the regulatory effect of ox-LDL on PERK/e IF2α/CHOP signaling pathway in vascular endothelial cells.Methods The effects of ox-LDL on PERK and p-e IF2α protein expression of primary human umbilical vein endothelial cells(HUVECs) were investigated by Western blot analysis.PERK gene silencing and selective eI F2α phosphatase inhibitor,salubrinal were used to inhibit the process of ox-LDL induced endothelial cell apoptosis,caspase-3 activity,and CHOP mR NA level.Results Ox-LDL treatment significantly increased the expression of PERK,PERK-mediated inactivation of e IF2α phosphorylation,and the expression of CHOP,as well as the caspase-3 activity and apoptosis.The effects of ox-LDL were markedly decreased by knocking down PERK with stable transduction of lentiviral sh RNA or by selective eI F2α phosphatase inhibitor,salubrinal.Conclusion This study provides the first evidence that ox-LDL induces apoptosis in vascular endothelial cells mediated largely via the PERK/eI F2α/CHOP ER-stress pathway.It adds new insights into the molecular mechanisms underlying the pathogenesis and progression of atherosclerosis.  相似文献   
58.
ScopeOxidized protein products (OPPs) can be easily found in meat and milk during processing and storage. Evidence supports that accumulation of endogenous OPPs plays a negative role in physiological metabolism. However, the impacts of dietary OPPs and the mechanisms have not been elucidated yet. The present study evaluated whether oral oxidized casein would destruct the antioxidant defense system and cause potential oxidized injury in mice liver and kidney.Methods and resultsWe performed oxidized casein (modified respectively by H2O2–Cu and HClO) feeding experiments using KM mice (20–22 g). A 10-weeks feeding of oxidized casein as basal protein caused oxidative stress by increasing protein carbonylation (PC), advanced oxidation protein products (AOPPs), dityrosine (Dityr), lipid peroxidation and ROS levels in mice liver, kidney and blood (P < 0.05). In mice liver and kidney, the mRNA expression of Nrf2, γ-GCS, HO-1, GPX-3, and GPX-4 up-regulated, the protein level of Nrf2 in nucleus increased. However, activities of anti-oxidant enzymes (CAT, SOD, and GPX) decreased (P < 0.05). Moreover, histopathological examination displayed the formation of fibrous septa in mice liver and kidney after oxidized casein feeding.ConclusionOxidized casein impairs antioxidant defense system and induces hepatic and renal fibrosis.  相似文献   
59.
60.
ObjectiveTo examine the frequency and outcomes of patients requiring renal replacement therapy (RRT) early after left ventricular assist device (LVAD) implantation.Patients and MethodsWe examined use of in-hospital RRT and outcomes in consecutive adults who underwent continuous-flow LVAD implantation from February 15, 2007, through August 8, 2017. Logistic regression was used to examine predictors of RRT. The associations of RRT with outcomes were examined using Cox proportional hazards regression.ResultsOf 354 patients who underwent LVAD implantation, 54 (15%) required in-hospital RRT. Patients receiving RRT had higher preoperative Charlson Comorbidity Index values (median, 5 vs 4; P=.03), Model for End-Stage Liver Disease scores (mean, 19.0 vs 14.5; P<.001), right atrial pressure (mean, 19.1 vs 13.4 mm Hg; P<.001), and estimated 24-hour urine protein levels (median, 357 vs 174 mg; P<.001) and lower preoperative estimated glomerular filtration rate (eGFR) (median, 43 vs 57 mL/min; P<.001) and measured GFR using 125I-iothalamate clearance (median, 33 vs 51 mL/min; P=.001) than those who did not require RRT. Approximately 40% of patients with eGFR less than 45 mL/min/1.73 m2 and 24-hour urine protein level greater than 400 mg required RRT vs 6% with eGFR greater than45 mL/min/1.73 m2 and without significant proteinuria. Lower preoperative eGFR, higher estimated 24-hour urine protein level, higher right atrial pressure, and longer cardiopulmonary bypass time were independent predictors of RRT after LVAD implantation. Of patients requiring in-hospital RRT, 18 (33%) had renal recovery, 18 (33%) required outpatient hemodialysis, and 18 (33%) died before hospital discharge. After median (Q1, Q3) follow-up of 24.3 (8.9, 49.6) months, RRT was associated with increased risk of death (adjusted hazard ratio [HR], 2.86; 95% CI, 1.90-4.33; P<.001) and gastrointestinal bleeding (adjusted HR, 4.47; 95% CI, 2.57-7.75; P<.001).ConclusionIn-hospital RRT is associated with poor prognosis after LVAD. A detailed preoperative assessment of renal function before LVAD may be helpful in risk stratification and patient selection.  相似文献   
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