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AIMS: Type 2 diabetes mellitus (DM) and coronary artery disease (CAD) are both associated with endothelial dysfunction and elevated oxidative and inflammatory state. We examined the effect of vitamin C on endothelial function and levels of soluble vascular cell adhesion molecule (sVCAM-1), interleukin-6 (IL-6) and tumour necrosis factor (TNF-alpha), in DM patients with or without CAD and in non-diabetic subjects. METHODS: Thirty-seven patients with DM + CAD, 17 patients with DM without CAD and 21 non-diabetic subjects were divided into groups receiving vitamin C 2 g/day or no anti-oxidant for 4 weeks. Forearm blood flow was determined using venous occlusion gauge-strain plethysmography. Forearm vasodilatory response to reactive hyperemia was considered as index of endothelium-dependent dilation. RESULTS: Baseline levels of IL-6 and TNF-alpha were significantly higher in patients with DM + CAD compared with patients with DM (P < 0.01) or non-diabetic subjects (P < 0.01). IL-6 and TNF-alpha levels were also higher in DM compared with non-diabetic subjects (P < 0.05). sVCAM-1 levels were lower in non-diabetic controls compared with DM + CAD (P < 0.05) or DM (P < 0.05). Reactive hyperaemia was higher in non-diabetic controls compared with DM + CAD (P < 0.001) or DM (P < 0.001). Vitamin C significantly increased reactive hyperaemia only in the DM + CAD group, while it had no effect on serum levels of sVCAM-1, TNF-alpha and IL-6 in any of the groups. CONCLUSIONS: Type 2 diabetes mellitus is associated with impaired endothelial function and increased levels of TNF-alpha, IL-6 and sVCAM-1, especially in patients with DM and CAD. Vitamin C significantly increased forearm vasodilatory response to reactive hyperaemia only in patients with combined DM and CAD.  相似文献   
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目的:观察青年和老年期大鼠下丘脑弓状核阿黑皮素原mRNA(POMC mRNA)的表达水平。方法应用原位杂交技术显示POMCmRNA和用计算机图像分析观察杂交信号的强弱及阳性细胞的面积,结果:与青年组相比,老年组下丘脑弓状核及其附近区域POMCmRNA阳性神经元的灰度下降,POMCmRNA阳性神经元的数目无明显变化,结论:老年期POMCmRNA阳性神经元相应的mRNA表达水平下降可能是下丘脑的POMC基因衍生肽表达水平下降的原因之一。  相似文献   
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畸变产物耳声发射用于新生儿听力筛查的影响因素分析   总被引:11,自引:4,他引:11  
目的 探讨畸变产物耳声发射(DPOAE)用于新生儿听力筛查的影响因素。方法 采用GSI-70全自动便携式耳声发射仪进行新生儿听力筛查,在筛查同时,自制问卷表,对新生儿的出生史,母亲妊娠史,家族史,父母社会阶层等35个因素进行调查,调查结果运用SPSS统计软件进行统计分析。结果 住院期间82.8%的(3242/3944)新生儿通过筛查,通过率右耳高于左耳,女婴高于男婴,单胎高于多胎,足月儿高于早产儿,正常及高出生体重儿高于低出生体重儿,阴道助产高于自然产、剖宫产,P值均小于0.05。多因素logistic回归分析,出生体重、性别、胎数与初筛结果相关。42天复筛,96.4%(3167/3284)通过筛查,影响初筛结果的因素对复筛无影响。结论 新生儿的性别、分娩方式、胎数、孕周、出生体重对应用DPOAE进行的新生儿听力筛查的初筛结果有显著影响。  相似文献   
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Hidradenitis suppurativa (HS) is an inflammatory skin disease with poorly understood immunopathogenic mechanisms. LL‐37 is an antimicrobial peptide, which is transcribed from the CAMP (cathelicidin antimicrobial peptide) gene. Previous reports showed upregulated levels of CAMP and LL‐37 in HS lesions, and therefore, the aim of this study was to compare levels of LL‐37 in HS to other inflammatory skin diseases and to establish immunomodulatory functions of LL‐37 in HS. We confirm an upregulation of the LL‐37 peptide in lesional HS skin with comparable levels as in psoriasis patients and are able to positively correlate the presence of LL‐37 in HS with the presence of T cells, macrophages, neutrophils, IFN‐γ, IL‐17, IL‐23, TNF‐α, IL‐32 and IL‐1β. Mechanistically, LL‐37 boosts the proliferation of unspecifically activated CD4+ T cells via an increased calcium signalling independent of antigen‐presenting cells. Targeting LL‐37 may therefore represent a new therapeutic option for the treatment of this recalcitrant disease, but it has to be kept in mind that LL‐37 also has an antimicrobial function.  相似文献   
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This study aimed to investigate if combined analysis of pro‐Neuropeptide Y (NPY) and ERG expression in tumor tissue are associated with biochemical failure (BF), castration‐based treatment, castration‐resistant prostate cancer (CRPC), and prostate cancer (PCa)‐specific death for men undergoing radical prostatectomy (RP) for PCa. This study included 315 patients, who underwent RP from 2002 to 2005. Both pro‐NPY and ERG expression were analyzed using immunohistochemistry and were scored as low or high and negative or positive, respectively. Risk of BF, castration‐based treatment, CRPC, and PCa‐specific death were analyzed with multiple cause‐specific Cox regression analyses and stratified cumulative incidences using competing risk assessment. Median follow‐up was 13.0 years (95% CI: 12.7–13.2). In total, 85.7% were pro‐NPY high and 14.3% were pro‐NPY low. The combined analyses of pro‐NPY and ERG expression was not associated with risk of BF (p = 0.7), castration‐based treatment (p = 0.8), CRPC (p = 0.4) or PCa‐specific death (p = 0.5). In the multiple cause‐specific Cox regression analysis, pro‐NPY high and ERG positivity was not associated with BF (HR: 1.02; 95% CI 0.6–1.7; p = 0.94). In conclusion the combination of pro‐NPY and ERG expression did not show association with risk of BF, castration‐based treatment, CRPC, and PCa‐specific death following RP.  相似文献   
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ObjectivesThe goal of this study was to examine prognostic relationships between cardiac imaging measures and cardiovascular outcome in people living with human immunodeficiency virus (HIV) (PLWH) on highly active antiretroviral therapy (HAART).BackgroundPLWH have a higher prevalence of cardiovascular disease and heart failure (HF) compared with the noninfected population. The pathophysiological drivers of myocardial dysfunction and worse cardiovascular outcome in HIV remain poorly understood.MethodsThis prospective observational longitudinal study included consecutive PLWH on long-term HAART undergoing cardiac magnetic resonance (CMR) examination for assessment of myocardial volumes and function, T1 and T2 mapping, perfusion, and scar. Time-to-event analysis was performed from the index CMR examination to the first single event per patient. The primary endpoint was an adjudicated adverse cardiovascular event (cardiovascular mortality, nonfatal acute coronary syndrome, an appropriate device discharge, or a documented HF hospitalization).ResultsA total of 156 participants (62% male; age [median, interquartile range]: 50 years [42 to 57 years]) were included. During a median follow-up of 13 months (9 to 19 months), 24 events were observed (4 HF deaths, 1 sudden cardiac death, 2 nonfatal acute myocardial infarction, 1 appropriate device discharge, and 16 HF hospitalizations). Patients with events had higher native T1 (median [interquartile range]: 1,149 ms [1,115 to 1,163 ms] vs. 1,110 ms [1,075 to 1,138 ms]); native T2 (40 ms [38 to 41 ms] vs. 37 ms [36 to 39 ms]); left ventricular (LV) mass index (65 g/m2 [49 to 77 g/m2] vs. 57 g/m2 [49 to 64 g/m2]), and N-terminal pro–B-type natriuretic peptide (109 pg/l [25 to 337 pg/l] vs. 48 pg/l [23 to 82 pg/l]) (all p < 0.05). In multivariable analyses, native T1 was independently predictive of adverse events (chi-square test, 15.9; p < 0.001; native T1 [10 ms] hazard ratio [95% confidence interval]: 1.20 [1.08 to 1.33]; p = 0.001), followed by a model that also included LV mass (chi-square test, 17.1; p < 0.001). Traditional cardiovascular risk scores were not predictive of the adverse events.ConclusionsOur findings reveal important prognostic associations of diffuse myocardial fibrosis and LV remodeling in PLWH. These results may support development of personalized approaches to screening and early intervention to reduce the burden of HF in PLWH (International T1 Multicenter Outcome Study; NCT03749343).  相似文献   
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