细胞因子与阿耳茨海默病

本文就细胞因子在阿耳茨海默病发病机制中的作用研究进展作一综述。     

细胞凋亡在阿耳茨海默病发病中的作用

细胞凋亡在阿耳茨海默病发病中的作用李晓东高枫综述陈清棠审校成年组织的发育与维持是通过细胞增殖与分化及程序化细胞死亡来获得。在程序化死亡发生过程中，细胞通过被称作细胞凋亡的自杀机制死亡［１，２］。细胞凋亡可以去除“不想要”的细胞，这种机制由激素、生长因...     

阿耳茨海默性痴呆与血管性痴呆的ApoE基因多态性研究

目的探讨ApoE基因在阿耳茨海默性痴呆（Alzheimer-typedementia,AD）与血管性痴呆（Vasculardementia,VD）患者当中的分布情况,以找出中国人的特点,评价ApoE基因检测在早期预测性诊断中的作用,比较AD与VD在ApoE基因多态性方面的异同。方法采用PCR-RFLP方法,对41例AD、35例VD和30例对照进行ApoE基因型测定。结果小于70岁的AD患者,其ε4等位基因频率大大高于同龄VD组患者和同龄对照组（P＜0.01和P＜0.05）。而≥70岁的AD患者ε4频率明显低于70岁以下AD患者（P＜0.01）。结论（1）ApoEε4与散发性AD之间具有明显相关性,其基因型以4/3为主,而ε4/4相对于国外文献报道要少。（2）AD组ε4等位基因频率高于VD组（P＜0.05）。（3）评价AD发病危险时,年龄因素不容忽视,70岁以下ε4携带者可能具有更高的AD发病危险性。     

磁共振血管造影的TCD检查与DSA诊断烟雾病的对比研究

目的 探讨磁共振血管造影（ＭＲＡ）结合经颅多普勒（ＴＣＤ）诊断烟雾病的可靠性。方法 对２２例成年人烟雾病患者的ＤＳＡ、ＭＲＡ及ＴＣＤ检查结果进行比较。结果 ＭＲＡ判断烟雾病血管狭窄程度和ＤＳＡ的符合率为７７．３％,另外２２．７％评估过度,ＭＲＡ示异常血管网（６３．６％）显著低于ＤＳＡ（８４．１％）;ＴＣＤ与ＤＳＡ符合率为７２．７％;ＭＲＡ和ＴＣＤ联合判断烟雾病血管狭窄程序与ＤＳＡ符合率为９３．２％,显著高于ＭＲＡ或ＴＣＤ。结论 ＭＲＡ和ＴＣＤ联合检查是诊断成年人烟雾病并作为长期随诊的理想方法。     

阿次海默病与Abeta的降解

自1907年始,阿尔次海默病（AD）就被定义为发生在记忆和认知功能脑区的病变：神经原纤维缠结（NFT）、老年斑（淀粉样斑块,SP）的形成以及神经元的进行性死亡。β-淀粉样蛋白（Aβ）是老年斑的主要成分,并且被认为在AD的发生和发展过程中起着很重要的作用。脑内Aβ的水平存在着一个动态平衡：一方面,由Aβ的前体蛋白（APP）经β泌肽酶和γ泌肽酶相继酶切后产生Aβ,进而形成寡聚体并且沉积形成老年斑;另一方面,Aβ可以被NEP等降解酶水解。而AD病人脑内的这一动态平衡被打乱了。在某些病理情况下（如缺氧或者缺血）或者随着年龄的增加,这些降解Aβ的酶的表达水平降低,这就会促进AD的发生。而相反的,以药理学等方法增加这些降解酶的活性,可以起到神经保护作用。这就为AD的治疗提供了一个新思维。     

褪黑素对阿茨海默病大鼠海马突触素表达的影响

目的 研究褪黑素(melatonin,MT)对阿茨海默病(Alzheimer's disease , AD)大鼠的海马突触素表达的影响.方法 大鼠随机分为4组,分别为AD组、AD-MT大剂量干预组、AD-MT小剂量干预组和假AD组.应用β-淀粉样蛋白(Aβ)注入大鼠海马CA1区,建立大鼠AD模型,AD-MT干预组随之以MT灌胃,1次/d,直至试验结束.应用电迷宫检测大鼠学习记忆情况,用免疫组化方法检测大鼠海马CA1区突触素的表达情况.结果 MT可以明显改善AD大鼠的学习记忆能力,提高大鼠海马CA1区突触素的阳性表达.结论 MT对AD大鼠有显著脑保护作用.     

TCD对180例头痛患者临床诊断价值分析

目的 为研究TCD检查对临床诊断偏头痛的价值。方法 应用TCD检测技术对临床上CT及MRI检查无异常且偏头痛正处于发作期的180例患者与128例无头痛症状，健康者者进行对比研究。结果 180例偏头痛患者血流速度异常加快，明显高于对比组。结论 TCD能准确的检测偏头痛患者发作期颅内段血流速度变化情况。     

阿茨海默(Alzheimer)病相关因素的研究现状

<正> 阿茨海默病是老年神经系统常见的退行性疾病,但导致本病的相关因素至今尚不十分清楚。以往的研究结果表明,年龄和受教育程度可能与阿茨海默病的患病率有关,例如65～74岁的老年人发病率约为1.45％,75～84岁者则增加至4.73％,而85岁以上的老年人更可高达9.11％,此外每增加1年受教育时间,可使阿茨海默病患病的危险性下降12％。近年来有关阿茨海默病相关因素的研究非常活跃,本文就近期的研究结果综述如下。 1 脱脂蛋白E(Apolipoprtein E,APOE) 研究发现,APOE与脂代谢、缺血性心脏病、脑血管淀粉样变性和人的寿命有关,也极有可能是导致阿茨海默病的原因之     

急性脑出血的TCD动态研究

我们使用TCD仪动态观察12例急性脑出血患者大脑前动脉、大脑中动脉和大脑后动脉的血液动力学变化,以探讨急性脑出血对脑血液动力学的影响。1　资料与方法1.1　临床资料　急性脑出血患者12例,男8例,女4例,平均年龄56.11岁,内囊出血5例,外囊出血3例,额叶出血2例,枕叶出血2例。出血30ml以下5例,30～40ml者3例,40～50ml者3例,50ml以上1例。所有患者均符合1995年全国第4届脑血管病会议通过的《各类脑血管疾病诊断要点》,并经脑CT或脑MRI检查证实。7例保守治疗,5例于发病3～10天内行经颅穿刺血肿抽吸术,无一例死亡。1.2　观察方法1.2.1　临床…     

检测脑脊液tau蛋白和天门冬氨酸转氨酶诊断阿耳茨海默病

阿耳茨海默病的神经元变性引起微管相关蛋白tau进入细胞间隙和脑脊液(CSF),在阿耳茨海默病和其它原因引起的痴呆病中,CSF中的tau蛋白浓度均可升高,这提示该蛋白的升高是非特异性的。     

Quantitative EEG mapping and PET in Alzheimer's disease

Quantitative analysis of topographical EEG was studied in comparison with measurement of regional glucose metabolism by PET in 42 patients with clinical diagnosis of probable dementia of Alzheimer type (AD) and in 15 age-matched normal controls. Measures analyzed included global and regional data from areas typically affected and not affected by AD pathology. While disturbance of metabolism followed a typical regional pattern, relative alpha, theta and delta power were more globally altered without selectivity for specific regions. Separation between AD and age matched controls by relative theta power was correct in 86% and was close to that by temporo-parietal glucose metabolism (correct classification 87%). Relative theta power as well as temporo-parietal glucose metabolism were significantly correlated (τ_B = 0.54 and −0.53, respectively) to severity of AD assessed by the global deterioration scale. These results indicate that EEG measures may be used with an accuracy close to metabolic values from PET for the assessment of severity of AD.     

Amyloid imaging in Alzheimer's disease

Alzheimer's disease (AD) is a complex neurodegenerative disorder of which the exact cause is still not known. There has, however, been remarkable progress in the understanding of the pathophysiological events that underlie the disease with a focus on amyloid formation. We do not know yet if amyloid is the most crucial target for an effective therapy in AD. The new amyloid PET imaging tracer ligands offer possibilities for measuring fibrillar beta amyloid (Abeta) in the brain and for studying the time course of amyloid in the brain. This opens up new possibilities for early diagnosis as well as new tools for monitoring anti-amyloid therapy in AD.     

Identifying functional imaging markers of mild cognitive impairment in early Alzheimer’s and Parkinson’s disease using multivariate analysis

Functional neuroimaging, such as positron emission tomography (PET) and single photon emission computed tomography (SPECT), provides a valuable technique for detecting regional changes in brain metabolic activity and blood flow associated with mild cognitive impairment (MCI) and dementia. Multivariate analysis techniques have recently received increasing attention. The results of multivariate analysis can be more easily interpreted as a signature of neuronal networks, which lend themselves to prospective application of results from the analysis of one dataset to entirely new datasets. They are well placed to provide information about mean differences and correlations with behavior with potentially greater statistical power and better reproducibility. This article will focus on investigating the baseline and progression of MCI using functional brain imaging techniques and multivariate analysis in order to understand the genesis and natural history of cognitive impairment in Alzheimer’s disease (AD) and Parkinson’s disease (PD), respectively.     

阿尔茨海默病~(18)F-FDG PET显像诊断的研究

目的 探讨阿尔茨海默病（AD）脑葡萄糖代谢及其18F-脱氧葡萄糖正电子发射计算机断层扫描（18F-FDG PET）显像的影像学特征和PET诊断标准。方法 静脉注射18F-FDG后行脑断层显像,检查13例 AD、13例非AD痴呆及13例正常人。获得纹状体、丘脑、黑质、顶叶、颞叶、额叶、枕叶、海马单位面积放射性计数与小脑计数的比值（Rcl/cb）,进行半定量分析,并与MR进行对照。结果AD患者PET异常率为100％,MR异常者占10/13。PET显像特征:①对称性双侧颞顶叶及海马伴额叶或枕叶代谢减低占9例（9/13）;②双侧颞叶对称性代谢减低伴海马或额叶代谢下降占3例（3/13）;③双顶叶对称性代谢降低1例（1/13）。12例（12/13）非AD痴呆表现为不对称、多发性代谢降低,降低区位于黑质、纹状体、丘脑及脑皮质区,MR异常率为11/13。结论 在除外脑内结构特异性损害基础上,PET发现对称性双颞顶叶、海马或颞叶、顶叶,伴或不伴枕叶、额叶代谢下降,可诊断AD。PET对AD早期诊断及鉴别诊断具有临床意义。     

The cerebral localization of neuropsychological impairment in Alzheimer's disease: a SPECT study

Summary Twenty-three patients with a clinical diagnosis of Alzheimer's disease were examined with a set of neuropsychological tests and with ^99mTc-hexamethyl-propyleneamineoxime (HMPAO) single photon emission computed tomography (SPECT). Correlations between test results and indices of regional HMPAO distribution were analysed by multidimensional scaling (MDS). Test results covaried positively with relative HMPAO uptake of frontal, inferior parietal and superior temporal regions but not, or in a negative way, with the remainder of the regions. When only positive correlations were analysed, MDS suggested two dimensions of organization: one was related to a dichotomy between frontal and temporo-parietal regions. The relationship of test results to this dimension was largely consistent with common neuropsychological knowledge. A second, less stringent dimension of organization opposed right and left hemisphere regions. The ordering of test results with respect to this dimension was only partly consistent with what is known about the lateralization of neuropsychological deficits from the study of localized brain lesions. The possibility is considered that these inconsistencies may reflect the effect of disproportionally severe involvement of extended cortical systems which modulates the sequels of localized brain damage.     

Disease-related and drug-induced changes in dopamine transporter expression might undermine the reliability of imaging studies of disease progression in Parkinson's disease

Parkinson's disease (PD) is a progressive neurodegenerative disorder. Standard therapeutic interventions are aimed at replenishment of empty dopamine stores with levodopa or substitution with dopamine receptor agonists. However, in the long term this symptomatic therapy fails. Currently, various neuroprotective agents are being developed, with the intention to slow down the degeneration of dopaminergic neurons. In this context, the early identification of persons at risk to develop the disease as well as the assessment of the effectiveness of putative neuroprotective agents, are critical issues. Dopamine transporter (DAT) scintigraphy with single photon emission computed tomography (SPECT) has been used to assess the dopaminergic function in PD. Initial studies with several radioligands show significant loss of DAT binding in PD patients as compared to controls. In this paper we review the evidence on the utility of DAT imaging with SPECT in early PD detection as well as in monitoring neurprotection.     

阿尔茨海默病^18F-AV45 PET脑显像的操作技术和临床应用

^18F-florbetapir(AV45)正电子发射断层成像(PET)脑显像作为阿尔茨海默病早期诊断的一类无创性影像学手段,目前在国内已经逐渐被认可。规范的检查流程、检查技术、图像解读及报告书写将有助于获得高质量的图像和准确的定量分析数据。因此,在参考国内外相关指南并结合国内现状及实际操作经验的基础上,我们介绍了^18F-AV45 PET脑显像的操作技术和临床应用的相关内容,以更好地促进国内^18F-AV45 PET脑显像检查的规范开展和临床应用研究的推广,为患者提供准确的影像诊断服务。     

A systematic review of molecular imaging (PET and SPECT) in autism spectrum disorder: Current state and future research opportunities

Non-invasive positron emission tomography (PET) and single-photon emission computed tomography (SPECT) are techniques used to quantify molecular interactions, biological processes and protein concentration and distribution. In the central nervous system, these molecular imaging techniques can provide critical insights into neurotransmitter receptors and their occupancy by neurotransmitters or drugs. In recent years, there has been an increase in the number of studies that have investigated neurotransmitters in autism spectrum disorder (ASD), while earlier studies mostly focused on cerebral blood flow and glucose metabolism. The underlying and contributing mechanisms of ASD are largely undetermined and ASD diagnosis relies on the behavioral phenotype. Discovery of biochemical endophenotypes would represent a milestone in autism research that could potentially lead to ASD subtype stratification and the development of novel therapeutic drugs. This review characterizes the prior use of molecular imaging by PET and SPECT in ASD, addresses methodological challenges and highlights areas of future opportunity for contributions from molecular imaging to understand ASD pathophysiology.     

PET对癫痫致痫区定位的研究进展

正电子发射型计算机断层显像（Positron Emission Computed Tomography ,PET ）是一种探测放射性示踪剂在体内分布及动态变化情况的显像技术,在神经功能影像学检查方法中,PET 目前被认为是癫痫外科术前评估的最佳无创性功能性影像检查方法［1］。 PET 利用不同种类的示踪剂,来探究脑组织葡萄糖代谢、氧代谢、脑血流灌注、神经受体分布、生化和蛋白合成等方面的变化,尤其对于结构影像学检查阴性的癫痫患者有很大的定位诊断价值［2－3］。     

Neuroanatomical correlates of low body weight in Alzheimer's disease: a PET study

Weight loss is a common problem in patients with Alzheimer's disease (AD) and this might be associated with an increased risk for mortality. Recent evidences have suggested that certain brain dysfunctions may result in impaired nutritional status in AD patients. However, the mechanism of body weight loss in AD remains enigmatic. To investigate a possible association between low body weight and regional brain dysfunction, the authors conducted the correlational analysis of body mass index (BMI) with regional brain glucose metabolism using positron emission tomography (PET) and [¹⁸F]fluorodeoxyglucose (FDG). Twenty-seven patients with probable AD were divided into two groups: the low BMI group and the normal BMI group. Regional brain glucose metabolic ratios were calculated using the cerebellar hemisphere as a reference region. Comparisons were made of regional brain metabolic ratios between the low BMI group and the normal BMI group. Correlations of the glucose metabolic ratio with BMI were also assessed in all patients with AD. In the comparison between the two groups, glucose metabolic ratio in the anterior cingulate cortex (ACC) was significantly lower in the low BMI group, whereas no significant differences were found in all the other brain regions. Furthermore, regional glucose metabolism in the ACC had a significant and positive correlation with BMI (r=.450, P=.018). After adjustment for age, gender and disease duration, regional glucose metabolism in the ACC was independently associated with BMI. Our findings suggest that the ACC may be preferentially involved in the regulation of nutritional status in AD patients, and provides a new insight into developing strategies for prevention and treatment of undernutritional demented patients.