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31.
Background and aimsIncreased alcohol consumption has been associated with CVD risk. Subclinical arterial damage (SAD) precedes the onset of cardiovascular disease (CVD), and allows early identification and study of the pathophysiology of CVD. Reliable, noninvasive vascular biomarkers are available for the early detection of SAD and reclassification of CVD risk. To investigate the association of alcohol consumption with multiple SAD biomarkers and central hemodynamics in a large sample of Greek adults with CVD risk factors.Methods and resultsThis cross-sectional study was conducted with 938 participants (43.5% men) and collected data on SAD biomarkers, central hemodynamics, and dietary intake. Multiple linear regression analysis was performed according to sex after adjusting for several confounders. In men, alcohol consumption of 20–30 g/d was positively associated with mean, diastolic, and peripheral systolic blood pressure (BP). The consumption of >30 g/d was positively associated with the augmentation index. In women, no statistically significant associations were found between alcohol consumption and BP or SAD indices. No statistically significant associations were found between alcohol consumption and arterial compliance or distensibility in both sexes.ConclusionIn men even a small deviation from the current recommendation for alcohol consumption is associated with both higher BP indices and pressure wave reflections. The absence of association in women might be due to very low alcohol intake, even in the high consumption group. More studies are needed to verify our findings and establish the above associations in each sex.  相似文献   
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青光眼是世界范围内导致不可逆失明的主要疾病,发病率逐年升高,视网膜神经节细胞(RGC)凋亡被认为是青光眼病变的最早形式。补体失调是青光眼早期视神经损害的特征改变,抑制补体系统能够阻止多种危险因素对RGC的损伤,可以在眼内压持续升高的情况下保护视网膜神经元树突和突触的完整性,阻止神经损伤进一步发展,是近年来青光眼视神经保护药物研发的热点。中草药来源的抗补体活性成分开发成本低,并可以直接在体内被利用,而且其对补体的调控是多成分,多途径的,因此,具有良好的应用前景。本文综述了补体系统在青光眼视神经损害中的病理机制和干预效应的研究进展,为进一步研究补体调控在视神经保护中的作用提供参考。  相似文献   
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BackgroundRubeosis faciei diabeticorum is a persistent facial erythema in patients with diabetes mellitus. The actual pathogenesis has not been studied. However, it is speculated to be a cutaneous diabetic microangiopathy.ObjectiveExamine the correlation between the severity of facial erythema and the possible causes of microvascular diabetic complications, namely oxidative stress, hyperglycemia, and cutaneous accumulation of advanced glycation end-products .MethodsPatients diagnosed with Type 2 diabetes mellitus (n = 32) were enrolled in the study. The facial erythema index was measured using the Mexameter MX18; cutaneous accumulation of advanced glycation end-products was estimated by measuring skin auto fluorescence with the AGE Reader (DiagnOptics Technologies B.V. – Groningen, Netherlands). Glycated haemoglobin, total antioxidant status, and malondialdehyde were measured in blood by TBARS assay. The correlation between the selected variables was assessed by Spearman's rank test; p  0.05 was considered statistically significant.ResultsThere was a statistically significant correlation between total antioxidant status and the facial erythema index (ρ = 0.398, p = 0.024). Malondialdehyde, skin autofluorescence, glycated haemoglobin, body mass index, duration of diabetes, and age did not demonstrate statistically significant correlation with the facial erythema index.Study limitationsThis is an observational study. Elevation of total antioxidant status could have been caused by several factors that might have also influenced the development of rubeosis faciei, including hyperbilirubinemia and hyperuricemia.ConclusionsThe results contradicted expectations. Total antioxidant status correlated positively with facial erythema index; however, there was no correlation with oxidative stress and skin autofluorescence. Further investigations should be conducted to reveal the cause of total antioxidant status elevation in patients with rubeosis faciei.  相似文献   
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Traumatic brain injury (TBI) is caused by a head impact with a force exceeding regular exposure from normal body movement which the brain normally can accommodate. People affected include, but are not restricted to, sport athletes in American football, ice hockey, boxing as well as military personnel. Both single and repetitive exposures may affect the brain acutely and can lead to chronic neurodegenerative changes including chronic traumatic encephalopathy associated with the development of dementia. The changes in the brain following TBI include neuroinflammation, white matter lesions, and axonal damage as well as hyperphosphorylation and aggregation of tau protein. Even though the human brain gross anatomy is different from rodents implicating different energy transfer upon impact, especially rotational forces, animal models of TBI are important tools to investigate the changes that occur upon TBI at molecular and cellular levels. Importantly, such models may help to increase the knowledge of how the pathologies develop, including the spreading of tau pathologies, and how to diagnose the severity of the TBI in the clinic. In addition, animal models are helpful in the development of novel biomarkers and can also be used to test potential disease‐modifying compounds in a preclinical setting.  相似文献   
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The implant surface must withstand high insertion torque during implant insertion. The aim of this study was to investigate the damage to implant surfaces caused by two different insertion protocols in vitro. Fifteen titanium implants per group were inserted in standardized polyurethane foam models, group 1 according to a non-threaded surgical protocol and group 2 according to a threaded surgical protocol. Before and after insertion, the surfaces were visualized by scanning electron microscopy (SEM) and non-contact laser profilometry. Different surface area parameters were evaluated and maximum torque during insertion was determined. SEM detected topographical changes such as deposition of the test block and smoothening of the surface in the region of the thread crests in both groups. The laser profilometry analysis revealed significant changes in the surface topography of the implants in both groups, but no differences between the groups. Insertion torque was significantly decreased in the threaded group. Both types of surgical intervention resulted in surface damage. Less damage was detected to the thread crests with the use of a thread cutter, and most of the surface was not visibly affected by the surgical protocol at the microscopic level. The surgical protocol seems to have a minor influence on preservation of the implant surface.  相似文献   
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我国心血管疾病的患病率及死亡率仍处于上升阶段,经皮冠状动脉介入治疗(PCI)是目前减少冠心病患者冠状动脉狭窄及闭塞和改善临床症状的最有效策略。临床上,存在很大一部分患者在大血管再通后,仍存在心痛症状。在PCI围术期常伴随着氧化应激、炎症、钙超载、内皮功能损害、血栓阻塞等不良事件,氧化应激在这个过程中扮演着重要角色。在PCI的再灌注时期,活性氧(ROS)的爆发可引发线粒体能量传递链异常和细胞离子稳态失衡,造成血管内皮细胞损伤,血管通透性增高,白蛋白漏出,白细胞和血小板黏附,血管狭窄。传统中医将PCI术后再狭窄纳入"胸痹"等范畴,气血的运行与五脏的功能密切相关,当气血运行不畅,心脏的生血、行血的功能受阻,造成气虚血瘀,从而造成机体虚损。目前,普罗布考和替格瑞洛等临床一线用药,具有一定的局限性,且忽略了"本虚邪实"的机体现状,无法协调机体气血阴阳五脏之间的关系。本研究从氧化应激在PCI损伤的现代医学分子研究出发,结合中医认识,总结中医药防治的研究进展,旨在为冠状动脉介入损伤的治疗提供候选药物及为相关实验研究提供参考。  相似文献   
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Bisphenol A (BPA), a well-recognized anthropogenic xenoestrogen, has been identified as a causative agent responsible for inducing carcinogenicity, cognitive impairment, neurotoxicity, oxidative stress, etc. However, BPA-induced neurotoxicity and its possible amelioration through natural compound intervention remain elusive. The current study was performed to elucidate the neurotoxic potential of BPA in zebrafish (Danio rerio) by waterborne exposure and its possible amelioration by quercetin co-supplementation. Protective effect of quercetin against BPA-induced altered neurobehavioral response, oxidative stress and neuromorphological changes were evaluated in zebrafish brain. The present findings reveal that BPA-induced altered neurobehavioral response was ameliorated by quercetin. Biochemical studies advocate the potential therapeutic efficacy of quercetin against BPA-induced oxidative stress in zebrafish brain. Quercetin also shows neuroprotection against BPA-induced augmented neuronal pyknosis in periventricular grey zone (PGZ) of zebrafish brain. These basic findings indicate that quercetin may act as an effective intervention against BPA-induced neurotoxicity in zebrafish through down-regulation of oxidative stress.  相似文献   
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