GABAARG2基因C588T多态性与癫痫的相关性研究

目的探讨中国粤西地区汉族人群GABAARG2基因C588T的单核苷酸多态性与癫痫的关系。方法采用病例-对照研究方法,收集粤西地区汉族人群189例癫痫患者,100例健康人作为正常对照组,根据患者对抗癫痫药物的反应性分为耐药组(92例)和药物敏感组(97例),提取所有研究对象外周血基因组DNA,采用PCR扩增后基因测序鉴定GABAARG2基因C588T多态性,测定该位点基因型频率和等位基因频率,并进行统计学分析。结果耐药组与药物敏感组、正常对照组的CC、CT、TT基因型频率及C、T等位基因频率比较差异均无统计学意义;药物敏感组与正常对照组的CC、CT、TT基因型频率比较(χ~2=6.468,P=0.039)差异有统计学意义,CC与CT优势比为1.669(95%CI=0.842~3.306,P=0.141),CC与TT的优势比为2.652(95%CI=1.240~5.668,P=0.011);C、T等位基因频率比较(χ~2=7.411,P=0.006)差异有统计学意义,C等位基因与T等位基因优势比为1.737(95%CI=1.166~2.588,P=0.006)。结论 GABAARG2基因5号外显子的C588T多态性与癫痫的易感性相关,但与癫痫的耐药风险不相关。     

结节性硬化症TSC2基因突变的分析

目的 分析结节性硬化症(TSC)致病基因TSC2突变方式.方法 采用聚合酶链反应-单链象多态性(PCR-SSCP)技术,对TSC一家系4例TSC患者(其中1例疑似)、1例散发性TSC患者外周血TSC2的41个外显子进行检测,并与家系中健康对照组和无血缘关系健康对照组进行比较.结果 此1家系中4例TSC患者(包括1例疑似)的TSC2基因外显子33发生了1346丝氨酸(S)→脯氨酸(P)(4037T→C)错义突变,1例散发性TSC患者及两健康对照组未检测到TSC2基因突变.结论 在TSC患者中TSC2外显子33错义突变(1346S→P,4037T→C)是一种尚未报道的新发现的基因突变方式.     

结节性硬化症TSC2基因5238-5255 del 18 bp及2713 C>T基因突变分析

目的检测并分析2例中国汉族结节性硬化症(tuberous sclerosis complex,TSC)患者TSC2基因突变特点。方法采用直接测序法对31个家系的34例TSC患者及其父母33名进行TSC1基因和TSC2基因全长编码外显子基因检测。测序后发现第25家系先证者为TSC2基因外显子40的框内移码突变5238-5255 del 18 bp,第11家系先证者为TSC2基因外显子23错义突变Arg905Trp。进一步采用变性凝胶电泳及内切酶技术在患者与120名正常对照中检测这两种突变。结果第25家系先证者外显子40出现5238-5255d el CATCAAGCGGCTCCGCCA突变,导致6个氨基酸缺失的框内移码突变(1746-1751del His-Ile-Lys-Arg-Leu-Gly),第11家系先证者外显子23出现2713 C>T(Arg905Trp)错义突变,2713位碱基由胞嘧啶(C)改变为胸腺嘧啶(T),导致第905位氨基酸精氨酸被色氨酸替代。120名正常对照未检测到这两种突变。结论TSC2基因5238-5255 del 18 bp及2713 C>T突变为两种致病性突变。     

胰岛素受体基因多态性与缺血性脑血管病的关系

目的 探讨胰岛素受体（IR）基因突变在缺血性脑血管病发病中的作用。方法 以PCR－单链构像多态性（PCR－SSCP）法对68例动脉粥样硬化性血栓性脑梗死（ACI）患者、81例腔隙性脑梗死（LI）患者及62名健康对照者（HC）检测IR基因第17和20外子碱基变异情况。结果 IR基因第17外显子存在C、T两种等位基因,ACI患者突变型T等位基因频率显著高于对照者,且突变型患者血压及血糖、血脂代谢指标均显著高于野生型对照者,但相关分析显示IR基因多态性与血压变化无关;第20外子未发现有碱基变异。结论 IR基因第17外显子突变可能通过促动脉粥样硬化而参与缺血性卒中发病。     

先天性肌强直一家系CLCN1基因突变的研究

目的 探讨先天性肌强直一家系CLCN1基因的突变方式.方法 采用PCR方法对1个先天性肌强直家系中的先证者、其祖母、父母、弟弟以及100名无血缘关系健康对照者的CLCN1基因全部外显子进行DNA测序.结果 先证者CLCN1基因第8及11号外显子各发现1个错义突变,分别是c.950G→A和c.1205C→T.其父亲有c.950G→A突变,其母亲有c.1205C→T突变.其弟及100名健康对照者未见上述突变.结论 CLCN1基因c.950G→A和c.1205C→T错义突变是该家系CLCN1基因的致病性突变.     

PINK1基因T313M多态性与新疆维吾尔族帕金森病的关系研究

目的探讨PINK1基因第4外显子T313M的多态性与新疆维吾尔族(维族)帕金森病(PD)的关系。方法对175例维族原发性PD患者(PD组)及163例维族健康体检者(对照组)提取基因组DNA,采用PCR扩增所需PINK1基因第4外显子T313M基因片段,用限制性内切酶酶切技术测定其基因型和等位基因,再进行测序分析验证。结果 PD组PINK1基因T313M的T/T基因型频率为2.9%,C/C基因型频率为97.1%,T等位基因频率为2.9%,C等位基因频率为97.1%;对照组PINK1基因T313M的T/T基因型频率为1.2%,C/C基因型频率为98.8%,T等位基因频率为1.2%,C等位基因频率为98.8%。两组间PINK1基因T313M多态性的比较差异无统计学意义(P0.05)。结论 PINK1基因第4外显子T313M多态性与新疆维族PD患者的遗传易感性无关。     

新疆维吾尔族、汉族阿尔茨海默病PLAU基因的多态性分析

目的探讨新疆维、汉两民族尿激酶型纤溶酶原激活因子(plasminogen activator urokinase,PLAU)基因6号外显子rs2227564位点C/T多态性同阿尔茨海默病(Alzheimer's disease,AD)的关联。方法在流行病学调查的基础上,采用美国神经病学会、语言障碍和卒中-老年性痴呆和相关疾病学会制定的标准,选取诊断很可能是AD的患者209例(汉族98例,维吾尔族111例)及正常对照220名(汉族103名,维吾尔族117名),应用聚合酶链反应-限制性片段长度多态性分析的方法,检测两组PLAU基因6号外显子rs2227564位点C/T多态性。结果 AD组和对照组、维吾尔族、汉族PLAU基因6号外显子rs2227564位点C/T基因型和等位基因频率的分布没有统计学差异(P0.05)。AD组和对照组维、汉两民族间PLAU基因6号外显子rs2227564位点C/T基因型和等位基因频率的分布没有统计学差异(P0.05)。不同性别中PLAU基因6号外显子rs2227564位点C/T的基因型和等位基因频率的分布没有统计学差异(P0.05)。结论未发现新疆维、汉两民族PLAU基因6号外显子rs2227564位点C/T多态性与AD存在相关性。     

中国汉族人群早发性帕金森综合征DJ-1基因突变分析

目的 探讨中国汉族人群早发性帕金森综合征(early-onset parkinsonism,EOP)DJ-1基因突变情况.方法 应用实时荧光定量聚合酶链反应(PCR)结合DNA直接测序技术对160例EOP患者进行了DJ-1基因突变分析.结果 对DJ-1基因外显子重排突变分析发现,4例新的DJ-1基因外显子2的杂合缺失突变,突变频率2.5%(4/160);DNA直接测序方法未发现DJ-1基因的致病突变,发现了4种已报道的单核苷酸多态(SNP)和1种新的SNP,分别为:IVS4+30 T→G、IVS4+45 G→A、IVS4+46 G→A、IVS5+31 G→A和IVS6+52 C→T.结论 DJ-1基因外显子2的杂合缺失突变扩展了DJ-1基因的突变谱,可能是中国汉族人群EOP DJ-1基因突变的重要形式.     

Alzheimer病患者淀粉样前体蛋白基因16、17外显子突变的研究

目的 探讨淀粉样β-蛋白(β/A_4)基因突变与Alzheimer病(AD)的关系。方法 运用限制性片段长度多态性(RFLP)和单链构象多态性(SSCP),检测分析20例散发性AD患者和8例正常老年人的淀粉样前体蛋白(APP)基因16、17外显子的多态性。结果 AD患者和正常对照的β/A_4基因均未发现C→T突变及其它异常SSCP泳动变位。结论 APP基因β/A_4编码区突变不是一突变“热点”,在AD不具有普遍意义。     

GCH1基因新的点突变的多巴反应性肌张力障碍1例报道并文献复习

目的 报道1例多巴反应性肌张力障碍(Doparesponsive dystonia, DRD)的三磷酸鸟苷环化水解酶I基因(Guanosine triphosphate cyclohydmlase I,GCH1)c.550C>T(p.R184C)杂合突变,并分析该基因突变患者的临床特点。方法 应用全外显子测序结合一代测序验证方法对1个家系的5名成员进行GCH1基因突变分析,并回顾既往文献进行疾病特点总结,以提高对DRD相关基因突变的临床特点及预后的认识。结果 5名家系成员中先证者及其一子一女 GCH1基因存在c.550C>T(p.R184C)杂合突变,且该点突变导致GCH1基因所编码的蛋白发生p.R184C错义突变(184位点上的精氨酸变为半胱氨酸)。软件分析显示c.550C>T(p.R184C)为可疑致病突变。结论 c.550C>T(p.R184C)突变可能是DRD新的致病位点,此分析扩展了DRD的GCH1基因突变内容,同时也为相关基因的功能验证提供了新的方向。     

Denervation study of synapses of organ of corti of old world monkeys

Fine structural characteristics of synapses in the spiral organ of Corti were examined, with reference to differences between inner and outer haircell systems, and to location of neurons of origin of efferent axons. Surgical interruption of crossed olivocochlear bundle, of vestibular nerve, of facial nerve, and excision of superior cervical ganglia were used to determine the pathways of efferent axons. Interruption of the vestibular nerve near the brainstem results in degeneration of all efferent terminals on outer hair cells. Mid-line lesions at, and caudal to, the facial colliculus result in degeneration of about half of these efferent terminals. Efferent synaptic bulbs to the inner hair-cell system are small, of the order of one micron, and form type 2 junctions with afferent dendrites. They tend to have more large dense-core vesicles (about 80 nm) than the large efferent terminals of the outer hair-cell system, and appear to be the terminals of axons in the habenula perforata, which exhibit varicosities laden with large dense core vesicles. The varicosities are unaffected by excision of the superior cervical ganglia. So far as our material can reveal, it appears that the varicosities in the habenula perforata do not survive vestibular root interruption, nor do the efferent processes in the internal spiral bundle or at the base of inner hair cells. Most interestingly, the afferent processes of the inner hair-cell system, as identified for example by their relation to pre-synaptic bodies in the inner hair cells, are subject to a trans-synaptic reaction after severance of the vestibular root. They undergo a dramatic cytological transformation, characterized by increase of volume, engorgement with microtubules, microfilaments, microvesicles of various sizes, and clusters of lysosomes. Thus, both the efferent and afferent terminals of the inner hair-cell system show marked cytological differences from the corresponding terminals of the outer hair cell system.     

Mechanism of action of tubocurarine on nicotinic cholinoreceptors of neurons of the sympathetic ganglia of rats

Tubocurarine (Tc) effect on membrane currents elicited by acetylcholine (ACh) was studied in isolated superior cervical ganglion neurons of rat using patch-clamp method in the whole-cell recording mode. The "use-dependent" block of ACh current by Tc was revealed in the experiments with ACh applications, indicating that Tc blocked the channels opened by ACh. Mean lifetime of Tc-open channel complex, tau, was found to be 9.8 +/- 0.5 s (n = 7) at -50 mV and 20-24 degrees C. tau exponentially increased with membrane hyperpolarization (e-fold change in tau corresponded to the membrane potential shift by 61 mV). Inhibition of the ACh-induced current by Tc (3-30 microM/1) was completely abolished by membrane depolarization to the level of 80-100 mV. Inhibition of ACh-induced current was augmented at increased ACh doses. It is concluded that the open channel block produced by Tc is likely to be the only mechanism for Tc action on nicotinic acetylcholine receptors in superior cervical ganglion neurons of rat.     

The effect of age of onset of PD on risk of dementia

Background Dementia occurs in the majority of patients with Parkinson’s disease (PD). Late onset of PD has been reported to be associated with a higher risk for dementia. However, age at onset (AAO) and age at baseline assessment are often correlated. The aim of this study was to explore whether AAO of PD symptoms is a risk factor for dementia independent of the general effect of age. Methods Two community-based studies of PD in New York (n = 281) and Rogaland county, Norway (n = 227) and two population-based groups of healthy elderly from New York (n = 180) and Odense, Denmark (n = 2414) were followed prospectively for 3–4 years and assessed for dementia according to DSM-IIIR. All PD and control cases underwent neurological examination and were followed with neurological and neuropsychological assessments. We used Cox proportional hazards regression based on three different time scales to explore the effect of AAO of PD on risk of dementia, adjusting for age at baseline and other demographic and clinical variables. Findings In both PD groups and in the pooled analyses, there was a significant effect of age at baseline assessment on the time to develop dementia, but there was no effect of AAO independent of age itself. Consistent with these results, there was no increased relative effect of age on the time to develop dementia in PD cases compared with controls. Interpretation This study shows that it is the general effect of age, rather than AAO that is associated with incident dementia in subjects with PD. Received in revised form: 22 December 2005     

Limits of deinstitutionalization--perspectives of relatives of psychiatric patients

After a hopeful beginning, the social process of the reintegration of those with severe mental illness has come to a standstill. I am led to wonder whether "the community" really wants to live together with people suffering from severe mental illness, and if so, how closely? As long as the medical treatment of mental illness provided by the general practitioners is fundamentally deficient, as they are not able to prescribe the necessary interventions--such as out-patient psychiatric nursing, and service providers in the out-patient sector are content with offering increasingly intensive forms of care for the less seriously ill at the cost of the Social Welfare System--the reintegration of those with serious mental illness remains an illusion--which is mainly to the benefit of providers of residential care in homes and hostels.