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51.
目的观察司来吉兰对帕金森病(PD)模型大鼠黑质纹状体内酪氨酸羟化酶(TH)及胶质细胞源性神经营养因子(GDNF)表达的影响,探讨司来吉兰对多巴胺能神经元的保护作用及机制。方法 72只健康雄性SD大鼠随机分为对照组、模型组和司来吉兰组,每组均设4 d和8 d 2个亚组,各12只。模型组和司来吉兰组采用颈背部皮下注射鱼藤酮制备PD模型,对照组皮下注射等体积葵花油。之后司来吉兰组每日灌胃咪多吡0.5 mg/kg,模型组和对照组每日灌胃等体积生理盐水,4 d和8 d组分别连续灌胃4 d和8 d。采用免疫组化法和Western blotting法检测黑质纹状体TH和GDNF表达水平。结果免疫组化法和Western blotting法检测结果均显示,对照组大鼠黑质纹状体可见多量TH阳性细胞表达和少量GDNF阳性细胞表达,8 d和4 d组差异均无统计学意义。模型组TH和GDNF阳性细胞表达均明显低于对照组(均P<0.05),8 d和4 d组差异均无统计学意义。司来吉兰组TH阳性细胞表达低于对照组而高于模型组,GDNF阳性细胞表达高于对照组和模型组(均P<0.05),且8 d组均高于4 d组(均P<0.05)。结论司来吉兰可减轻PD模型大鼠黑质纹状体多巴胺能神经元的损伤,其作用机制可能与增加GDNF表达有关。  相似文献   
52.
目的比较纳米铅和常规铅暴露对生长发育期仔鼠海马及皮质的氧化损伤作用。方法将30只健康妊娠SPF级SD大鼠随机分为3组,分别为对照(生理盐水)组、纳米铅(10 mg/kg)组和常规铅(100 mg/kg)组,每组10只。采用经口灌胃方式进行染毒,自母鼠妊娠至仔鼠断乳(PND21)。记录仔鼠的出牙时间、睁眼时间、翻正反射时间、爬行时间、张耳时间、断崖回避时间,采用Morris水迷宫对PND21仔鼠进行学习记忆能力测试,分别于PND1、PND21检测仔鼠海马和皮质中的铅、活性氧(ROS)、蛋白质糖基化终产物(AGEs)含量和抑制羟自由基能力。结果与对照组比较,纳米铅及常规铅暴露后仔鼠翻正反射时间、爬行时间及张耳时间延长,学习记忆能力降低;皮质、海马中铅、ROS和AGEs含量增高,而抑制羟自由基能力降低,差异均有统计学意义(P0.05)。与常规铅组比较,纳米铅组PND21仔鼠皮质和海马中ROS水平均升高,PND1时纳米铅组仔鼠海马抑制羟自由基能力下降,纳米铅暴露组PND21仔鼠海马和皮质中AGEs含量增高,差异均有统计学意义(P0.05)。结论纳米铅和常规铅染毒可导致仔鼠生长发育期迟缓及皮质、海马的氧化应激,且随着染毒时间延长,纳米铅暴露致仔鼠皮质和海马氧化损伤程度高于常规铅暴露,这可能与纳米材料的特性有关。  相似文献   
53.
目的探索ARIMA模型在我国梅毒发病率预测中的应用,为提出相应的预防措施提供依据。方法收集2004年1月-2012年12月我国梅毒发病率资料,用SPSS13.0拟合ARIMA模型,并用2013年每月的数据评价模型的预测效果。结果 ARIMA(1,1,0)×(2,1,1)12模型为预测我国梅毒发病率的最佳模型,预测值和实际值的动态趋势基本一致。并用此模型对2014年每月我国梅毒发病率进行了预测。结论 ARIMA模型是一种短期内预测精度较高的预测模型,预测效果可靠。  相似文献   
54.
Reduced arterial elasticity and endothelial dysfunction both may indicate early cardiovascular (CV) disease in young adults. Pulse waveform analysis estimates large (LAE) and small (SAE) artery elasticity noninvasively. We assessed the associations between LAE and SAE and markers of endothelial dysfunction and CV risk factors. The Coronary Artery Risk Development in Young Adults (CARDIA) assessed arterial elasticity and other characteristics cross-sectionally in 389 men and 381 women age 27 to 42 years in 1995 (CARDIA year 10) and circulating levels of P-selectin and soluble intercellular adhesion molecule 1 (sICAM1) in 2000. We adjusted for variables included in the estimation of arterial elasticity (year 10 height, body mass index, age, heart rate, and blood pressure) and other year 10 characteristics. Mean adjusted SAE was 8.5 vs. 7.6 mL/mm Hg × 100 in those with urine albumin/creatinine ratio ≤4 vs. microalbuminuria (ratio >25; Ptrend = .008). Mean LAE was 25.6 vs. 24.2 mL/mm Hg × 10 in the lowest vs. highest quintile of P-selectin (Ptrend = .004). sICAM1 was unrelated to either LAE or SAE. Plasma triglycerides were inversely related to LAE (Ptrend = .029). Cigarette smokers had lower SAE than nonsmokers (Ptrend = .009). In addition to smoking and triglycerides, biomarkers for endothelial dysfunction were associated with impaired LAE and SAE in young adults.  相似文献   
55.
This study explores the prevalence and factors associated with back pain and treatment seeking of older people. We used data from the Longitudinal Aging Study in India (LASI), 2017-18. A sample of 31,464 older adults aged 60 years and above was considered for this study. Chi-square test was used to find the significance level for bivariate associations. Additionally, Heckprobit selection model was employed to fulfill the objectives. Among 34% of the participants suffering from back pain, 46.2% used external application, followed by analgesics (40.8%) and therapy (6.6%). Older adults with higher education had a higher probability of seeking therapy than those with no or primary education [β:0.25; CI:0.03,0.48]. Participants from the highest wealth quintile had higher probability of seeking therapy than those from the lowest [β:0.41; CI:0.23,0.58]. The use of therapy, which is globally recommended first line of management for back pain, was least utilized and must be promoted.  相似文献   
56.
Low-dose repeated lipopolysaccharide pre-challenge followed by chronic mild stress (LPS/CMS) protocol has been introduced as a rodent model of depression combining the roles of immune activation and chronic psychological stress. However, the impact of this paradigm on cognitive functioning has not been investigated hitherto.MethodsThis study evaluated LPS/CMS-induced cognitive effects and the role of glycogen synthase kinase-3β (GSK-3β) activation with subsequent neuroinflammation and pathological tau deposition in the pathogenesis of these effects using lithium (Li) as a tool for GSK-3 inhibition.ResultsLPS pre-challenge reduced CMS-induced neuroinflammation, depressive-like behavior and cognitive inflexibility. It also improved spatial learning but increased GSK-3β expression and exaggerated hyperphosphorylated tau accumulation in hippocampus and prefrontal cortex. Li ameliorated CMS and LPS/CMS-induced depressive and cognitive deficits, reduced GSK-3β over-expression and tau hyperphosphorylation, impeded neuroinflammation and enhanced neuronal survival.ConclusionThis study draws attention to LPS/CMS-triggered cognitive changes and highlights how prior low-dose immune challenge could develop an adaptive capacity to buffer inflammatory damage and maintain the cognitive abilities necessary to withstand threats. This work also underscores the favorable effect of Li (as a GSK-3β inhibitor) in impeding exaggerated tauopathy and neuroinflammation, rescuing neuronal survival and preserving cognitive functions. Yet, further in-depth studies utilizing different low-dose LPS challenge schedules are needed to elucidate the complex interactions between immune activation and chronic stress exposure.  相似文献   
57.
PurposeCerebral microbleeds (CMBs) are considered essential indicators for the diagnosis of cerebrovascular disease and cognitive disorders. Traditionally, CMBs are manually interpreted based on criteria including the shape, diameter, and signal characteristics after an MR examination, such as susceptibility-weighted imaging or gradient echo imaging (GRE). In this paper, an efficient method for CMB detection in GRE scans is presented.Materials and methodsThe proposed framework consists of the following phases: (1) pre-processing (skull extraction), (2) the first training with the ground truth labeled using CMB, (3) the second training with the ground truth labeled with CMB mimicking the same subjects, and (4) post-processing (cerebrospinal fluid (CSF) filtering). The proposed technique was validated on a dataset of 1133 CBMs that consisted of 5284 images for training and 1737 images for testing. We applied a two-stage approach using a region-based CNN method based on You Only Look Once (YOLO) to investigate a novel CMB detection technique.ResultsThe sensitivity, precision, F1-score and false positive per person (FPavg) were evaluated as 80.96, 60.98, 69.57 and 6.57, 59.69, 62.70, 61.16 and 4.5, 66.90, 79.75, 72.76 and 2.15 for YOLO with a single label, YOLO with double labels, and YOLO + CSF filtering, respectively, and YOLO + CSF filtering showed the highest precision performance, F1-score and lowest FPavg.ConclusionsUsing proposed framework, we developed an optimized CMB learning model with low false positives and a balanced performance in clinical practice.  相似文献   
58.
Increasing evidence indicates that a disturbance of normal iron homeostasis and an amyloid-β (Aβ)-iron interaction may contribute to the pathology of Alzheimer's disease (AD), whereas iron chelation could be an effective therapeutic intervention. In the present study, transgenic mice expressing amyloid precursor protein (APP) and presenilin 1 and watered with high-dose iron served as a model of AD. We evaluated the effects of intranasal administration of the high-affinity iron chelator deferoxamine (DFO) on Aβ neuropathology and spatial learning and memory deficits created in this AD model. The effects of Fe, DFO, and combined treatments were also evaluated in vitro using SHSY-5Y cells overexpressing the human APP Swedish mutation. In vivo, no significant differences in the brain concentrations of iron, copper, or zinc were found among the treatment groups. We found that high-dose iron (deionized water containing 10 mg/mL FeCl3) administered to transgenic mice increased protein expression and phosphorylation of APP695, enhanced amyloidogenic APP cleavage and Aβ deposition, and impaired spatial learning and memory. Chelation of iron via intranasal administration of DFO (200 mg/kg once every other day for 90 days) inhibited iron-induced amyloidogenic APP processing and reversed behavioral alterations. DFO treatment reduced the expression and phosphorylation of APP protein by shifting the processing of APP to the nonamyloidogenic pathway, and the reduction was accompanied by attenuating the Aβ burden, and then significantly promoted memory retention in APP/PS1 mice. The effects of DFO on iron-induced amyloidogenic APP cleavage were further confirmed in vitro. Collectively, the present data suggest that intranasal DFO treatment may be useful in AD, and amelioration of iron homeostasis is a potential strategy for prevention and treatment of this disease.  相似文献   
59.
目的 观察抑郁症大鼠杏仁核磷酸化微管相关蛋白-2(pMAP-2)表达和神经元凋亡的变化,探讨抑郁症的发病机制。方法 随机将20只雄性Wistar大鼠分为对照组和模型组,采用慢性不可预见性温和应激(CUMS)方法建立抑郁大鼠模型,采用糖水偏好实验、悬尾实验、Morris水迷宫实验进行行为学检测,免疫印迹方法检测pMAP-2变化,透射电镜观察神经细胞凋亡。结果 模型组体重增长率、糖水偏好百分比低于对照组( P <0.05),悬尾不动时间和逃避潜伏期长于对照组( P <0.05);模型组pMAP-2蛋白表达高于对照组( P <0.05);模型组观察到明显的神经细胞凋亡。结论 抑郁症大鼠杏仁核神经细胞凋亡增加,可能与MAP-2磷酸化增高有关。  相似文献   
60.
 目的: 通过观察血管紧张素转换酶2(ACE2)基因敲除(KO)小鼠止血带休克(TS)后肾组织血管紧张素转化酶/血管紧张素Ⅱ(ACE/AngⅡ)的表达及损伤程度的变化,探讨ACE2在休克后急性肾损伤中的作用。方法: 小鼠双下肢用止血带结扎缺血2 h、松带后再灌注4 h复制TS模型。将雄性6月龄野生型(WT)C57BL/6小鼠和相同背景的ACE2 KO小鼠各12只分为4组,即WT组、WT+TS组、KO组和KO+TS组,每组6只。Western blotting测肾组织ACE蛋白的表达;ELISA法测定肾组织AngⅡ表达;利用化学比色方法测定肾组织丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性、血尿素氮(BUN)和血清肌酐(Cr)含量。结果: 与WT小鼠相比,WT+TS小鼠肾组织ACE/AngⅡ表达明显增加,出现肾组织氧化应激损伤和功能改变;与WT小鼠相比,KO小鼠肾组织ACE/AngⅡ表达增加,但未见明显的氧化应激损伤和功能变化;与WT+TS小鼠相比,KO+TS小鼠肾ACE/AngⅡ表达进一步增加,肾组织氧化应激和肾功能损伤明显加重。结论: ACE2基因缺失可能通过增加ACE/AngⅡ表达加重止血带休克肾的氧化应激损伤,针对ACE2靶f点的药物有可能成为防治止血带休克时急性肾损伤的策略之一。  相似文献   
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