遗传性痉挛性截瘫spastin、atlastin和paraplegin基因突变分析

目的探讨遗传性痉挛性截瘫(HSP)spastin、atlastin和parap legin基因的突变特点。方法应用聚合酶链反应-单链构象多态性(PCR-SSCP)结合DNA序列分析方法对24个常染色体显性遗传HSP家系和14例散发患者进行spastin基因和atlastin基因突变分析;对12个常染色体隐性遗传HSP家系和14例散发患者进行parap legin基因突变分析。结果在5个不同的常染色体显性遗传HSP家系中发现4个spastin基因新突变(1223 insCTCA、1258T→A,1293A→G和1668delCTA),在2例散发患者中发现2个spastin基因多态(IVS1-31C→G和IVS2-47A→G);在常染色体显性遗传HSP家系和散发患者中未发现atlastin基因突变或多态;在常染色体隐性遗传HSP家系和散发患者中未发现致病突变,仅在2例散发患者中发现2个parap legin基因多态(2063G→A及2066G→A)。结论我国遗传性痉挛性截瘫患者中spastin基因突变较常见,atlastin和parap legin基因的突变率可能较低。     

遗传性痉挛性截瘫atlastin基因突变分析

目的 探讨中国人遗传性痉挛性截瘫（HSP）atlastin基因的突变特点,为HSP的基因诊断奠定基础。方法 应用聚合酶链反应一单链构象多态性（PCR-SSCP）结合DNA序列分析方法,对来自全国20例常染色体显性遗传HSP家系的先证者和10例散发性HSP患者进行了atlastin基因突变分析。结果 在20例常染色体显性遗传HSP家系的先证者和10例散发性HSP患者中均未发现异常SSCP条带,第7号外显子直接DNA序列分析亦无异常。结论 atlastin基因突变可能在中国人HSP患者中少见。     

伴皮质下梗死及白质脑病常染色体显性遗传性脑动脉病的NOTCH3基因诊断

目的 分析伴皮质下梗死及白质脑病常染色体显性遗传性脑动脉病((CADASIL)的NOTCH3基因突变类型.方法 对临床诊断为CADASIL的4例先证者、来自3个家系10例患者及4例无类似临床表现成员、以及100名健康对照者进行NOTCH3基因PCR扩增及变性高压液相色谱分析(DHPLC)检测;对DHPLC阳性结果进行DNA双向测序,明确致病性突变或多态类型.结果 在CADASIL先证者及其家系患者中共发现134半胱氨酸→酪氨酸(Cys134Tyr)、141精氨酸→半胱氨酸(Arg141Cys)、90精氨酸→半胱氨酸(Arg90Cys)3种突变类型,存在于第3、第4外显子,为杂合错义突变.同时发现15种多态类型.其中家系1和家系2中分别发现1名成员与先证者存在相同位点的NOTCH3基因致病性突变,尚未出现与先证者相应的临床表现,被确定为临床前期患者.结论 NOTCH3单基因突变是CADASIL的分子遗传学基础,第3、4外显子可能是中国CADASIL家系的热点突变区.第4外显子Cys134Tyr突变类型为国内首次报告.     

遗传性痉挛性截瘫SPG4和SPG3A基因突变和多态分析

目的 筛查并分析遗传性痉挛性截瘫(HSP)SPG4和SPG3A基因突变,了解中国人群这2个基因的突变特点.方法 联合应用变性高效液相色谱分析(DHPLC)和DNA序列分析方法对24例常染色体显性遗传的HSP(AD-HSP)家系的先证者和32例散发性HSP患者进行SPG4和SPG3A基因突变筛查,对24例AD-HSP家系的先证者进一步直接测序筛查这2个基因的突变.结果 在1个AD-HSP家系中发现1个位于SPG4基因上的新犁突变1616+1g→t杂合突变.在此家系中,共发现了3例现症患者和2例症状前患者.本组病例未检出SPG3A基因突变.此外,共发现了8种新的SPG4多态和3种新的SPG3A多态.结论 本组检测结果 丰富了SPG4和SPG3A基因的突变和多态库.这2个基因突变在本组病例中较少见,需要继续分析其他基因.     

SURF1基因604G→C杂合性错义突变所致Leigh综合征患儿的临床与分子遗传学研究

目的研究因常染色体SURF1基因突变所致Leigh综合征患儿及其家系的临床与分子遗传学特点。方法收集39例Leigh综合征患儿及其家属的外周血白细胞脱氧核糖核酸(DNA),运用聚合酶链反应(PCR)扩增SURF1基因的全部外显子序列,进行正反向序列测定检测突变,采用限制性片段长度多态性(RFLP)分析验证测序结果,并与100名健康成人对照。结果39例Leigh综合征患儿中有5例(12.8%)SURF1基因外显子7存在604G→C杂合性错义突变。5例患儿(男3例,女2例)均因智力或运动障碍于出生后8个月至9.8年来院就诊。其中3例患儿的父母接受了SURF1基因突变分析,发现双亲中一方SURF1基因存在604G→C杂合性错义突变,而另一方及健康对照的相关外显子序列未发现异常。结论我们首次报道了5例SURF1基因604G→C杂合性错义突变导致Leigh综合征的患儿及其家系,频度高达12.8%,提示该突变可能是中国人的热点突变。我们的研究将有助于今后Leigh综合征患者的诊断和遗传咨询。     

贵州部分少数民族遗传性痉挛性截瘫Spastin基因突变研究

目的筛查及分析遗传性痉挛性截瘫(HSP)Spastin基因突变,了解贵州地区少数民族(彝族、布衣族、苗族)Spastin基因突变特点。方法应用PCR产物直接DNA测序法,对9例HSP患者(包括3个家系中7例现证者和2例散发患者)Spastin基因1-17号外显子进行突变筛查;被发现存在突变的外显子,其次行家系内其他成员相对应外显子的筛查。结果在9例HSP患者中发现家系3两例患者(Ⅴ24、Ⅴ25)的Spastin基因第4号外显子同一位点上发生错义突变c.847C>T,其他参与抽血的亲属均无该位点突变,推测该位点的突变为一多态。另外的突变位点均位于外显子序列前后的内含子区域。结论此次贵州地区部分少数民族spastin基因突变率低,与国内文献报道的汉族人群不同。     

一个2A型肢带型肌营养不良家系CAPN3基因的突变分析

目的对一个2A型肢带型肌营养不良(limb-girdle muscular dystrophy type 2A)家系进行CAPN3基因的致病突变分析。方法收集先证者及家系成员的外周血,提取DNA,应用全外显子测序技术对先证者进行致病基因检测,然后用Sanger测序技术对先证者家系成员进行突变位点的验证。结果全外显子测序发现先证者携带CAPN3基因c. 1194-9A G和c. 1437C T (p. ser479=)的复合杂合突变。Sanger测序验证先证者母亲为CAPN3基因c. 1194-9A G变异携带者。家系中其他患者均存在相同的复合杂合突变,其未发病的姐姐和女儿为CAPN3基因c. 1437C T (p. ser479=)变异携带者,先证者的女婿未检测到上述位点变异。结论 CAPN3基因c. 1194-9A G和c. 1437C T (p. ser479=)的复合杂合突变为该家系的致病原因。     

一个肾上腺脑白质营养不良家系的ABCD1基因突变分析

目的 通过对1例疑似肾上腺脑白质营养不良(ALD)患者及该家系其他成员进行ALD基因分析来明确诊断. 方法 从患者和家庭成员的外周血白细胞提取总RNA和基因组DNA:应用RT-PCR技术,首先对先证者cDNA的ABCD1基因编码区进行序列分析,寻找突变位点,再通过PCR和直接测序等方法 进一步确证该突变位点;同时对该家系其他成员的相应基因组DNA进行ABCD1基因分析. 结果 先证者的ABCD1基因第656(G)、657(A)位碱基缺失,造成移码突变fs R89,可以确诊为ALD.该家系其他成员基因突变分析结果 为:先证者表弟存在与先证者相同的突变,为ALD半合子;先证者的母亲、小姨、表妹均为ALD携带者;先证者姐姐为ABCD1正常基因型. 结论 在中国人ALD患者中发现了1个新的ABCD1基因突变(fs R89),ABCD1基因突变分析是诊断X-ALD最可靠的方法 .     

家族性低钾型周期性麻痹基因型和表型分析

研究背景分析一中国汉族家族性低钾型周期性麻痹家系的致病基因和相关临床资料。方法采用DNA序列技术对先证者(Ⅲ3)进行CACNA1S、SCN4A、KCNE3全基因组筛查,针对检测到的变异进一步检测家系中其他患者和无症状家系成员是否存在相同基因突变,经对临床资料分析以确定相关基因突变是否为致病性突变基因。结果先证者(Ⅲ3)及家系中其他患者(Ⅱ1、Ⅲ4、Ⅳ3)均检测到CACNA1S基因IVS25-194C/T突变,而无症状家系成员(Ⅲ1)未检测到该突变;该家系成员(除Ⅰ1)均检测到SCN4A基因IVS18-130G/A突变,该位点位于内含子区域且有症状和无症状家系成员同时出现;先证者(Ⅲ3)和无症状家系成员(Ⅲ1)同时检测到SCN4A基因外显子12区域c.1984GA突变,系错义突变(V662I),但家系中其他患者(Ⅱ1、Ⅲ4、Ⅳ3)均未发现该位点突变。结论结合临床资料和生物信息学预测,推测CACNA1S、SCN4A、KCNE3基因突变均非该家系致病性突变基因。但该家系资料丰富了我国原发性低钾型周期性麻痹家系的临床和基因数据库。除KCNE3、CACNA1S和SCN4A基因外,中国低钾型周期性麻痹家系可能存在新的致病基因突变,尚待进一步研究。     

遗传性痉挛性截瘫2家系的临床特点与spastin基因突变分析

目的:探讨2个家系遗传3代以上常染色体显性遗传性痉挛性截瘫(AD-HSP)的临床特点及其与spastin基因突变的关系。方法:对2个AD-HSP家系进行详细的临床检查,总结所有患者临床特点,并应用PCR技术结合DNA序列分析方法,检测2家系先证者spastin基因的突变情况。结果:2家系中所有患者均具有HSP的典型表现,PCR-DNA序列分析2例先证者spastin基因的17个外显子均未发现有异常突变。结论:2家系HSP患者具有典型的AD-HSP临床表现,并非spastin基因外显子突变所致。     

Epilepsy and anomalies of neuronal migration: MRI and clinical aspects

Neuronal migration disorders are the result of disturbed brain development. In such disorders, neurons are abnormally located. In diagnosing these conditions, magnetic resonance imaging is superior to any other imaging technique. This enables us to improve our knowledge of the clinical correlates of neuronal migration. With reference to migrational disorder, a retrospective study of all 303 patients with epileptic seizures referred for magnetic resonance imaging during a 3-year period was performed, 13 patients (aged 12-41, mean age 27) were identified. They represent 4.3% of the entire study group. Of the patients with known epilepsy, 6.7% and of the mentally retarded, 13.7% had migrational disorders. Four patients had schizencephaly as the dominant finding, one was classified as hemimegalencephaly, 2 had isolated heterotopias, and 6 had localized pachy- and/or poly-microgyria. The clinical pictures are complex. Ectopias of grey matter are recognised foci of epilepsy, but from an epileptological and a clinical viewpoint little attention has been given to these disorders. The present study shows that malmigration is not rare in epilepsy patients, especially not in the mentally retarded.     

Hepatic Considerations in the Use of Antiepileptic Drugs

Summary: Virtually all of the major antiepileptic drugs (AEDs) can cause hepatotoxicity, although fatal hepatic reactions are rare. The mechanisms, incidences, and risk profiles for such reactions differ from drug to drug. With carbamazepine and phenytoin, hepatotoxicity may be due to drug hypersensitivity. Although the profiles of patients at risk have not been well-defined for these two antiepileptic drugs, it would appear from reports in the literature that older adolescents and adults are at higher risk than children of developing serious or fatal hepatotoxicity. Once hepatotoxicity develops, mortality rates are 10–38% with phenytoin and 25% for carbamazepine. The risk profile for valproate fatal hepatotoxicity has been more clearly defined. Those at primary risk of fatal hepatic dysfunction are children under the age of 2 years who are receiving multiple anticonvulsants and also have significant medical problems in addition to severe epilepsy. The risk is considerably lower for patients over the age of 2 years on valproate monotherapy. In contrast to the risk profile with other AEDs, adults receiving valproate as monotherapy have the lowest risk of hepatotoxicity. Fatal hepatic dysfunction coincident with valproate may be the result of aberrant drug metabolism. Concomitant use of AEDs that induce microsomal P450 enzymes (e.g., phenytoin and phenobarbital) may enhance the production of a toxic metabolite, and hence the greater risk of hepatotoxicity with polypharmacy.     

Vascular Malformations and Epilepsy: Clinical Considerations and Basic Mechanisms

Summary: Vascular malformations (VMs) are associated with epilepsy. The natural history of the various VMs, clinical presentation, and tendency to provoke epilepsy determine treatment strategies. Investigations have probed the mechanisms of epileptogenesis associated with these lesions. Electrophysiologic changes are associated with epileptogenic cortex adjacent to VMs. Putative pathophysiologic mechanisms of epileptogenesis include neuronal cell loss, glial proliferation and abnormal glial physiology, altered neurotransmitter levels, free radical formation, and aberrant second messenger physiology.     

Classification of methods in transcranial Electrical Stimulation (tES) and evolving strategy from historical approaches to contemporary innovations

Transcranial Electrical Stimulation (tES) encompasses all methods of non-invasive current application to the brain used in research and clinical practice. We present the first comprehensive and technical review, explaining the evolution of tES in both terminology and dosage over the past 100 years of research to present day. Current transcranial Pulsed Current Stimulation (tPCS) approaches such as Cranial Electrotherapy Stimulation (CES) descended from Electrosleep (ES) through Cranial Electro-stimulation Therapy (CET), Transcerebral Electrotherapy (TCET), and NeuroElectric Therapy (NET) while others like Transcutaneous Cranial Electrical Stimulation (TCES) descended from Electroanesthesia (EA) through Limoge, and Interferential Stimulation. Prior to a contemporary resurgence in interest, variations of transcranial Direct Current Stimulation were explored intermittently, including Polarizing current, Galvanic Vestibular Stimulation (GVS), and Transcranial Micropolarization. The development of these approaches alongside Electroconvulsive Therapy (ECT) and pharmacological developments are considered. Both the roots and unique features of contemporary approaches such as transcranial Alternating Current Stimulation (tACS) and transcranial Random Noise Stimulation (tRNS) are discussed. Trends and incremental developments in electrode montage and waveform spanning decades are presented leading to the present day. Commercial devices, seminal conferences, and regulatory decisions are noted. We conclude with six rules on how increasing medical and technological sophistication may now be leveraged for broader success and adoption of tES.     

Carbamazepine Efficacy and Utilization in Children

Summary: Carbamazepine is effective for preventing partial and generalized tonic-clonic seizures in children. Although absence epilepsies are more common in children than adults, an estimated 80% of children with epilepsy have seizure types or epilepsies that are potentially responsive to carbamazepine. The differential diagnosis of ictal staring is an especially important issue in children because absence and atypical absence seizures are more prevalent in children than adults. Age-related pharmacokinetic differences and drug interactions are major considerations in children. On average, children have higher clearance rates of carbamazepine, shorter half-lives, and higher ratios of carbamazepine-10, 11-epoxide to carbamazepine than adults. In addition, children with severe epilepsy are more likely to require multiple-drug therapy, which can lead to complex drug interactions. When carbamazepine is administered along with valproate, drug protein binding interactions can cause intermittent side effects.     

Neonatal Seizures: Problems in Diagnosis and Classification

Summary: The clinical identification of neonatal seizures is critical for the recognition of brain dysfunction; however, diagnosis is often difficult because of the poorly organized and varied nature of these behaviors. Current classification systems are limited in their ability to communicate motor, autonomic, and electroencephalo-graphic features of seizures precisely and to provide a basis for uniform effective diagnosis, therapy, and determination of prognosis. Recent investigations of neonates, utilizing bedside electroencephalographic/polygraphic/ video monitoring techniques, have provided the basis for improved diagnosis and classification of seizures in the newborn. These studies have demonstrated that not all clinical phenomena currently considered to be seizures require electrocortical epileptiform activity for their initiation or elaboration. In addition, the specific clinical character of the phenomena considered to be seizures, the clinical state of the infant, and the character of the EEG indicate the probable pathophysiological mechanisms involved and suggest probable etiologies, prognosis, and therapy. Similarities between animal models that demonstrate reflex physiology and neonates with motor automatisms and tonic posturing suggest that these clinical behaviors may not be epileptic in origin but, rather, primitive movements of progression and posture mediated by brainstem mechanisms. Although not all clinical behaviors currently considered to be neonatal seizures may have similar pathophysiological mechanisms, they are clinically significant because they all indicate brain dysfunction.     

Valproate Monotherapy in the Management of Generalized and Partial Seizures

Summary: For decades, therapeutic tradition has promoted the concept of polypharmacy in the management of epilepsy. In recent years, however, studies have shown that, for most patients, monotherapy can provide comparable or better seizure control than administration of multiple anticonvulsants, while diminishing the potential for adverse reactions, drug interactions, and poor compliance. Valproate is an important monotherapeutic agent that is highly effective in the control of idiopathic primary and secondarily generalized epilepsies, and partial seizures that do not generalize. Comparative studies have found that valproate is at least as effective as phenytoin and carbamazepine in the treatment of generalized and partial seizures. Given the similar efficacy, other factors such as pharmacokinetics and side effects may therefore determine anticonvulsant selection for monotherapy.     

Un nouveau cadre conceptuel de travail pour la psychiatrie

In an attempt to place psychiatric thinking and the training of future psychiatrists more centrally into the context of modern biology, the author outlines the beginnings of a new intellectual framework for psychiatry that derives from current biological thinking about the relationship of mind to brain. The purpose of this framework is twofold. First, it is designed to emphasize that the professional requirements for future psychiatrists will demand a greater knowledge of the structure and functioning of the brain than is currently available in most training programs. Second, it is designed to illustrate that the unique domain which psychiatry occupies within academic medicine, the analysis of the interaction between social and biological determinants of behavior, can best be studied by also having a full understanding of the biological components of behavior.