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71.
Alzheimer's disease (AD) is the most common cause of dementia in late life. It is difficult to precisely diagnose AD at early stages, making biomarker search essential for further developments. The objective of this study was to identify protein biomarkers associated with aluminum ions toxicity (AD-like toxicity) in a human neuroblastoma cell model, SH-SY5Y and assess potential prevention by NAP (NAPVSIPQ). Complete proteomic techniques were implemented. Four proteins were identified as up-regulated with aluminum ion treatment, CBP80/20-dependent translation initiation factor (CTIF), Early endosome antigen 1 (EEA1), Leucine-rich repeat neuronal protein 4 (LRRN4) and Phosphatidylinositol 3-kinase regulatory subunit beta (PI3KR2). Of these four proteins, EEA1 and PI3KR2 were down-regulated after NAP-induced neuroprotective activity in neuroblastoma cells. Thus, aluminum ions may increase the risk for neurotoxicity in AD, and the use of NAP is suggested as a treatment to provide additional protection against the effects of aluminum ions, via EEA1 and PI3KR2, associated with sorting and processing of the AD amyloid precursor protein (APP) through the endosomal system.  相似文献   
72.
73.
BackgroundThe abnormal alcohol consumption could cause toxicity and could alter the human brain’s structure and function, termed as alcohol used disorder (AUD). Unfortunately, the conventional screening methods for AUD patients are subjective and manual. Hence, to perform automatic screening of AUD patients, objective methods are needed. The electroencephalographic (EEG) data have been utilized to study the differences of brain signals between alcoholics and healthy controls that could further developed as an automatic screening tool for alcoholics.MethodIn this work, resting-state EEG-derived features were utilized as input data to the proposed feature selection and classification method. The aim was to perform automatic classification of AUD patients and healthy controls. The validation of the proposed method involved real-EEG data acquired from 30 AUD patients and 30 age-matched healthy controls. The resting-state EEG-derived features such as synchronization likelihood (SL) were computed involving 19 scalp locations resulted into 513 features. Furthermore, the features were rank-ordered to select the most discriminant features involving a rank-based feature selection method according to a criterion, i.e., receiver operating characteristics (ROC). Consequently, a reduced set of most discriminant features was identified and utilized further during classification of AUD patients and healthy controls. In this study, three different classification models such as Support Vector Machine (SVM), Naïve Bayesian (NB), and Logistic Regression (LR) were used.ResultsThe study resulted into SVM classification accuracy = 98%, sensitivity = 99.9%, specificity = 95%, and f-measure = 0.97; LR classification accuracy = 91.7%, sensitivity = 86.66%, specificity = 96.6%, and f-measure = 0.90; NB classification accuracy = 93.6%, sensitivity = 100%, specificity = 87.9%, and f-measure = 0.95.ConclusionThe SL features could be utilized as objective markers to screen the AUD patients and healthy controls.  相似文献   
74.
目的观察阿尔茨海默病(AD)发病进程中海马结构在断层影像上的形态学改变。方法依据AD发病进程,分别采集正常对照(NC)组、轻度认知损害(MCI)组、AD组各34例共102例受试者脑核磁共振图像,每组男、女各17例。观测海马面积、横径、矢径和颞叶钩回间距、颞角宽度等。分析组间各测量值变化趋势,以及海马面积等相关测量值与各神经评定量表评分的相关性。结果各组海马面积侧别均无统计学差异。各组间测量值比较,AD组海马面积小于NC组及MCI组(P均<0.05);AD组海马横径小于NC组及MCI组,MCI组海马横径小于NC组(P均<0.01);AD组颞叶钩回间距大于NC组及MCI组(P均<0.01),MCI组颞叶钩回间距大于NC组(P<0.05)。海马面积、海马横径与临床痴呆分级量表(CDR)及汉密尔顿抑郁量表(HAMD)评分均呈负相关,与蒙特利尔认知评估量表(MoCA)评分均呈正相关;颞叶钩回间距与神经心理量表评分相关性同海马面积、海马横径相反。结论海马面积与海马横径随AD病情进展逐渐缩小,颞叶钩回间距随AD病情进展逐渐增大;海马结构的改变可损伤其认知功能。  相似文献   
75.
BACKGROUND & AIMS: Eosinophilic esophagitis (EE) is frequently associated with atopic disease, including dermatitis and asthma. Data are emerging that atopic skin may provide an early entry point for antigen sensitization. We aimed to test the hypothesis that epicutaneous exposure to antigen primes for subsequent respiratory antigen-induced EE. METHODS: Wild-type and genetically engineered mice were subjected to epicutaneous antigen sensitization and the development of experimental EE, and immune responses were examined. RESULTS: We show that exposure to antigen via the epicutaneous route primes for marked eosinophilic inflammation in the esophagus triggered by a single airway antigen challenge. The development of experimental EE is associated with significant skin eosinophilia, accelerated bone marrow eosinophilopoiesis, blood eosinophilia, and large increases in serum antigen-specific immunoglobulin G1/immunoglobulin E using ovalbumin or Aspergillus fumigatus as the epicutaneous antigen. Mechanistic analysis with gene-targeted mice showed that interleukin-5 was required for esophageal eosinophilia and that interleukin-4, interleukin-13, and STAT6 contributed to a lesser extent. CONCLUSIONS: These findings provide the first evidence that epicutaneous exposure to allergens potently primes for EE via a Th2-dependent mechanism.  相似文献   
76.
APP.V717I and Tau.P301L transgenic mice develop Alzheimer's disease pathology comprising important aspects of human disease including increased levels of amyloid peptides, cognitive and motor impairment, amyloid plaques and neurofibrillary tangles. The combined model, APP.V717I × Tau.P301L bigenic mice (biAT mice) exhibit aggravated amyloid and tau pathology with severe cognitive and behavioral defects. In the present study, we investigated early changes in synaptic function in the CA1 and CA3 regions of acute hippocampal slices of young APP.V717I, Tau.P301L and biAT transgenic animals. We have used planar multi-electrode arrays (MEA) and improved methods for simultaneous multi-site recordings from two hippocampal sub-regions. In the CA1 region, long-term potentiation (LTP) was severely impaired in all transgenic animals when compared with age-matched wild-type controls, while basal synaptic transmission and paired-pulse facilitation were minimally affected. In the CA3 region, LTP was normal in Tau.P301L and APP.V717I but clearly impaired in biAT mice. Surprisingly, frequency facilitation in CA3 was significantly enhanced in Tau.P301L mice, while not affected in APP.V717I mice and depressed in biAT mice. The findings demonstrate important synaptic changes that differ considerably in the hippocampal sub-regions already at young age, well before the typical amyloid or tau pathology is evident.  相似文献   
77.

Objective

To characterize the end-of-life care of all international patients who died at a global destination medical center from January 1, 2005, through December 31, 2015.

Patients and Methods

We performed a retrospective review of all adult international patients who died at a global destination medical center from January 1, 2005, through December 31, 2015.

Results

Eighty-two international patients from 25 countries and 5 continents died during the study period (median age, 59.5 years; 59% male). Of the study cohort, 11% (n=9) completed an advance directive, 61% (n=50) died in the intensive care unit, 26% (n=21) had a full code order at the time of death, and 73% (n=19 of 26) receiving cardiopulmonary resuscitation did not survive the resuscitation process.

Conclusion

Seriously ill international patients who travel to receive health care in the United States face many barriers to receiving high-quality end-of-life care. Seriously ill international patients are coming to the United States in increasing numbers, and little is known about their end-of-life care. There are many unique needs in the care of this complex patient population, and further research is needed to understand how to provide high-quality end-of-life care to these patients.  相似文献   
78.

Background

Atopic dermatitis (AD) is exacerbated by sweating, and the skin of most patients with AD are resided by Malassezia (M.) fungi. Recently, MGL_1304 produced by Malassezia globosa was identified as the major histamine releasing antigen in human sweat.

Methods

The full length cDNA of the counterpart of MGL_1304 in Malassezia restricta (Mala r 8), was cloned by degenerate PCR and rapid identification of cDNA ends (RACE). Recombinant MGL_1304, and its counterparts, Mala s 8 (produced by Malassezia sympodialis) and Mala r 8 were prepared, and compared in their allergenicities by dot blot analysis and histamine release tests with sera and basophils of patients with AD.

Results

The identities between MGL_1304 and Mala s 8, MGL_1304 and Mala r 8, and Mala s 8 and Mala r 8 were 68%, 78%, and 76%, respectively, in protein sequences. Dot blot analysis revealed that the level of IgE binding to Mala s 8 was higher than that of MGL_1304. However, histamine release tests revealed that MGL_1304 and Mala r 8 possessed higher activity than Mala s 8. In addition, the crude lysate of M. globosa showed higher histamine release ability than that of M. sympodialis.

Conclusions

Patients with AD showed hypersensitivities against MGL_1304 and its homologs. However, the allergenicities of the homologs are variable and the histamine release activities may be different from the solid-phase binding activities for IgE. Sweat allergy should be carefully evaluated with biological activities of MGL_1304 and its homologs of other Malassezia fungi residing on the skin.  相似文献   
79.
目的 研究辛伐他汀对铜和高胆固醇诱导的阿尔茨海默病(AD)家兔海马淀粉样肽前蛋白(APP)mRNA表达的影响.方法 采用Sparks方法复制铜和高胆固醇诱导的AD家兔模型.辛伐他汀(5 mg·kg-1·d-1)灌胃3 w,高效液相色谱法(HPLC)检测家兔海马胆固醇含量,实时定量RT-PCR法检测海马APP mRNA表达水平.分析海马胆固醇含量与海马APP mRNA表达的相关性.结果 模型组海马胆固醇含量及APP mRNA表达水平显著高于正常组(P<0.05).辛伐他汀组海马胆固醇含量及APP mRNA表达水平显著低于模型组(P<0.05);与正常组相无显著差别(P>0.05).海马APP mRNA表达水平与海马胆固醇含量呈正相关(r=0.58,P<0.05).结论 辛伐他汀可通过降低海马胆固醇含量减少APP转录,这可能是辛伐他汀降低AD发病的机制.  相似文献   
80.
目的研究铝中毒性拟老年痴呆症(AD)小鼠模型的建立方法及中药制剂海尔福口服液对其治疗效果。方法选用昆明种小白鼠76只,分成两批进行实验。第一批36只,分成正常组、模型组、治疗组,后2组用氯化铝灌胃造模115 d,治疗组于造模第8周开始用海尔福口服液1号和2号治疗;第二批40只,分成正常组、模型组、海1组、海2组,后3组用氯化铝和硝酸铝喂养造模3个月,海1组和海2组于造模第8周开始分别用海尔福口服液1号和2号治疗。实验前后测定第一批小鼠的大脑乙酰胆碱酯酶(AchE)活性、ALT及血红蛋白,实验结束测定第二批小鼠AchE活力及血清和脑匀浆各项生化指标。结果第一批:模型组小鼠AchE活性明显高于正常组和治疗组(P<0.01),血红蛋白明显低于2组(P<0.01),血清ALT各组之间无明显差异;第二批:模型组AchE活性明显低于其余3组,而脑O.-2浓度、脑谷胱苷肽过氧化物酶活性、血清尿素含量明显高于其余3组。结论铝中毒性拟老年痴呆症表现在对大脑胆碱能系统的损害,模型小鼠脑AchE活性均明显下降;对氧自由基清除力也明显下降,同时对血红蛋白有一定的影响。而中药制剂海尔福口服液对其有明显的治疗作用。  相似文献   
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