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61.
《Clinical neurophysiology》2020,131(7):1444-1452
ObjectiveTo investigate cognitive functions in non-demented patients with early-onset Parkinson's disease (PD), and to compare PARK2 gene mutation carriers and non-carriers by means of event-related brain potentials (ERPs).MethodsThe participants comprised patients with early-onset PD (EOPD) and healthy controls (HC). Patients with EOPD were divided into two groups as carriers of known pathogenic variants of PARK2 gene (EOPD-PC) and non-carriers of genes involved in familial PD (EOPD-NC). ERP data were collected during auditory oddball and visual continuous performance test (CPT).ResultsBoth EOPD groups (EOPD-PC and EOPD-NC) displayed reduced and delayed P3 in response to oddball target and CPT NoGo. CPT Go P3 was reduced in EOPD-NC but not in EOPD-PC. Oddball target N1 was reduced and P2 was enhanced in both EOPD-PC and EOPD-NC. In both cognitive tasks, RTs were prolonged and accuracy was lower in EOPD-PC and EOPD-NC.ConclusionsWe found several EOPD-related neurophysiologic changes, implying impairments in cognitive functions. Pairwise comparisons between EOPD-PC and EOPD-NC revealed no significant ERP marker.SignificanceIn this study, the confounding effect of normative aging was somewhat excluded compared with many previous studies. In contrast with the many oddball studies in non-demented PD, we clearly observed reduced and prolonged P3 in early-onset PD. Our NoGo P3 findings also contribute to the limited ERP research concerning response inhibition.  相似文献   
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目的 探究醛糖还原酶和晚期糖基化终末产物受体对糖尿病视网膜病变神经元凋亡的影响。方法 Wistar大鼠36只,随机分为对照组、模型组、转染组,后两组建立糖尿病大鼠模型。模型建立成功后,构建含有晚期糖基化终末产物受体siRNA的质粒并利用慢病毒转染入转染组大鼠体内。造模后4周、8周、12周,记录各组大鼠体质量及空腹血糖。造模后9周,禁食6 h,测定口服葡萄糖耐量。造模后12周,处死全部大鼠后,TUNEL法检测各组大鼠视网膜神经元凋亡情况,荧光分光光度计测定醛糖还原酶活性,Western blotting法测定晚期糖基化终末产物受体的表达,RT-PCR检测视网膜中Bcl-2和Bax mRNA相对表达量。结果 造模后4周、8周、12周,转染组和模型组的大鼠体质量均低于对照组(均为P<0.05);造模后12周,转染组大鼠体质量高于模型组(P<0.05)。造模后4周、8周、12周,各组内大鼠空腹血糖水平均无明显变化(均为P>0.05),转染组和模型组大鼠的空腹血糖水平均高于对照组(均为P<0.05)。模型组和转染组大鼠在口服葡萄糖后30 min时,血糖水平均高于对照组(均为P<0.05);在120 min时分别下降至最低,但仍高于对照组(均为P<0.05)。模型组和转染组的视网膜神经元凋亡指数、醛糖还原酶活性、晚期糖基化终末产物受体和Bax mRNA相对表达量均高于对照组(均为P<0.05),且转染组均高于模型组(均为P<0.05)。模型组和转染组的Bcl-2 mRNA相对表达量均低于对照组(均为P<0.05),转染组低于模型组(P<0.05)。结论 晚期糖基化终末产物结合受体后产生大量的氧自由基损伤,可能是导致糖尿病视网膜神经元凋亡,进而导致糖尿病视网膜病变发生的机制之一。  相似文献   
64.
目的:观察电针双侧"足三里"穴对脾气虚模型大鼠小肠黏膜上皮组织内的钠依赖葡萄糖转运体(SGLT1),葡萄糖运载蛋白2(GLUT2)的基因及蛋白表达的影响。方法:将40只SD雄性大鼠随机分为正常组、脾气虚组、足三里组、非经非穴组,每组10只。所有大鼠均在SPF级动物实验中心饲养。除正常组外,其余3组均采用劳倦过度和不规则饮食复合法建立脾气虚证的大鼠模型。造模成功之后,对足三里组、非经非穴组大鼠分别进行电针"足三里"穴、非经非穴点干预处理7天。采用HE染色方法观察各组大鼠小肠黏膜组织形态变化;采用荧光定量PCR法检测大鼠小肠黏膜上皮的SGLT1和GLUT2的mRNA表达水平;采用蛋白质免疫印迹法(WB)检测大鼠小肠黏膜上皮组织内的SGLT1和GLUT2的蛋白含量变化。结果:脾气虚组大鼠小肠黏膜组织部分损伤,足三里组的小肠黏膜组织有一定程度的恢复;脾气虚组和非经非穴组大鼠小肠黏膜组织内的SGLT1和GLUT2蛋白和基因表达水平均明显低于正常组(P 0. 05);足三里组大鼠小肠黏膜组织内的SGLT1和GLUT2蛋白和基因表达水平相比于脾气虚组有所升高(P 0. 05),非经非穴组未见显著性差异(P 0. 05)。结论:电针"足三里"穴可以调节脾气虚大鼠小肠黏膜上皮组织内的SGLT1和GLUT2基因及蛋白的异常表达,参与小肠对葡萄糖的吸收作用进而改善脾气虚证。  相似文献   
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ResearchGate is a world wide web for scientists and researchers to share papers, ask and answer questions, and find collaborators. As one of the more than 15 million members, the author uploads research output and reads and responds to some of the questions raised, which are related to type 2 diabetes. In that way, he noticed a serious gap of knowledge of this disease among medical professionals over recent decades. The main aim of the current study is to remedy this situation through providing a comprehensive review on recent developments in biochemistry and molecular biology, which can be helpful for the scientific understanding of the molecular nature of type 2 diabetes. To fill up the shortcomings in the curricula of medical education, and to familiarize the medical community with a new concept of the onset of type 2 diabetes, items are discussed like: Insulin resistance, glucose effectiveness, insulin sensitivity, cell membranes, membrane flexibility, unsaturation index (UI; number of carbon-carbon double bonds per 100 acyl chains of membrane phospholipids), slow-down principle, effects of temperature acclimation on phospholipid membrane composition, free fatty acids, energy transport, onset of type 2 diabetes, metformin, and exercise. Based on the reviewed data, a new model is presented with proposed steps in the development of type 2 diabetes, a disease arising as a result of a hypothetical hereditary anomaly, which causes hyperthermia in and around the mitochondria. Hyperthermia is counterbalanced by the slow-down principle, which lowers the amount of carbon-carbon double bonds of membrane phospholipid acyl chains. The accompanying reduction in the UI lowers membrane flexibility, promotes a redistribution of the lateral pressure in cell membranes, and thereby reduces the glucose transporter protein pore diameter of the transmembrane glucose transport channel of all Class I GLUT proteins. These events will set up a reduction in transmembrane glucose transport. So, a new blood glucose regulation system, effective in type 2 diabetes and its prediabetic phase, is based on variations in the acyl composition of phospholipids and operates independent of changes in insulin and glucose concentration. UI assessment is currently arising as a promising analytical technology for a membrane flexibility analysis. An increase in mitochondrial heat production plays a pivotal role in the existence of this regulation system.  相似文献   
67.
COVID-19 is a novel coronavirus disease with a higher incidence of bilateral pneumonia and pleural effusion. The high pulmonary tropism and contagiousness of the virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), have stimulated new approaches to combat its widespread diffusion. In developing new pharmacological strategies, the chemical characteristic of volatility can add therapeutic value to the hypothetical drug candidate. Volatile molecules are characterized by a high vapor pressure and are consequently easily exhaled by the lungs after ingestion. This feature could be exploited from a pharmacological point of view, reaching the site of action in an uncommon way but allowing for drug delivery. In this way, a hypothetical molecule for COVID-19 should have a balance between its lung exhalation characteristics and both antiviral and anti-inflammatory pharmacological action. Here, the feasibility, advantages, and disadvantages of a therapy based on oral administration of possible volatile drugs for COVID-19 will be discussed. Both aerosolized antiviral therapy and oral intake of volatile molecules are briefly reviewed, and an evaluation of 1,8-cineole is provided in view of a possible clinical use and also for asymptomatic COVID-19.  相似文献   
68.
AimsWe previously showed that the protective effects of endothelial progenitor cells (EPCs)‐released exosomes (EPC‐EXs) on endothelium in diabetes. However, whether EPC‐EXs are protective in diabetic ischemic stroke is unknown. Here, we investigated the effects of EPC‐EXs on diabetic stroke mice and tested whether miR‐126 enriched EPC‐EXs (EPC‐EXsmiR126) have enhanced efficacy.MethodsThe db/db mice subjected to ischemic stroke were intravenously administrated with EPC‐EXs 2 hours after ischemic stroke. The infarct volume, cerebral microvascular density (MVD), cerebral blood flow (CBF), neurological function, angiogenesis and neurogenesis, and levels of cleaved caspase‐3, miR‐126, and VEGFR2 were measured on day 2 and 14.ResultsWe found that (a) injected EPC‐EXs merged with brain endothelial cells, neurons, astrocytes, and microglia in the peri‐infarct area; (b) EPC‐EXsmiR126 were more effective than EPC‐EXs in decreasing infarct size and increasing CBF and MVD, and in promoting angiogenesis and neurogenesis as well as neurological functional recovery; (c) These effects were accompanied with downregulated cleaved caspase‐3 on day 2 and vascular endothelial growth factor receptor 2 (VEGFR2) upregulation till day 14.ConclusionOur results indicate that enrichment of miR126 enhanced the therapeutic efficacy of EPC‐EXs on diabetic ischemic stroke by attenuating acute injury and promoting neurological function recovery.  相似文献   
69.
【摘要】 报道临床症状不典型的家族性黑棘皮病1家系。先证者女,4岁,自1周岁时,颈部、腹部出现黑色斑片,近年来逐渐扩大至唇周、躯干前部。腹部皮肤全反式共聚焦显微镜检查可见乳头环下延扭曲及沟壑结构,乳头环内可见中高折光颗粒结构。先证者父亲及祖母既往有类似病史,但随着年龄增长色素沉着自发性消退,仅有局部皮纹增粗。采集先证者及父母、祖母外周血,对先证者外周血DNA行Panel靶向测序,结果显示,先证者存在FGFR3基因14号外显子c.1949A>C(p.Lys650Thr)错义突变,Sanger测序验证证实先证者及其父亲和祖母均存在此突变。诊断:家族性黑棘皮病。  相似文献   
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