PLA2G6基因多态性与偏执型精神分裂症的关联

目的：探讨PLA2G6基因多态性与偏执型精神分裂症的关系.方法：采用聚合酶链反应（PCR）和限制性内切酶片段长度多态性（RFLP）方法,在109个偏执型精神分裂症患者核心家系中检测PLA2G6基因上的3个单核苷酸多态性（SNP）（rs2235346、rs2272831和rs2284060）.运用单倍型相对风险（HRR）分析和传递不平衡分析（TDT）方法进行关联分析.结果：所检测的3个SNPs的基因型在患者组和父母组中频数分布均符合Hardy-Weinberg平衡.HRR和TDT分析均表明,rs2272831位点与偏执型精神分裂症相关联（χ^2=5.590,υ=1,P=0.018;χ^2=5.333,υ=1,P=0.021）,而rs2235346和rs2284060位点与偏执型精神分裂症无关联.结论：PLA2G6基因可能是偏执型精神分裂症的易感基因.     

精神病混合家系GRIK2基因多态性的关联研究

目的　在中国汉族人群混合家系中探讨GRIK2基因多态性与精神分裂症、心境障碍是否 关联。方法　采用PCR RFLP技术对GRIK2基因多态性rs6922753(T/C)和rs2227283(G/A)分型,进行 传递不平衡检验(TDT)。结果　(1)rs6922753多态性与精神分裂症(χ2=3.13,P>0.05)或心境障碍 (χ2=3.20,P>0.05)无关联,但在发病年龄≤25岁的患者中与两组疾病均相关联(P<0.05);(2) rs2227283多态性与精神分裂症(χ2=9.85,P<0.01)、心境障碍(χ2=13.50,P<0.01)呈显著关联;(3) 双位点TDT提示单体型TG、CA与精神分裂症、心境障碍相关联(P<0.05)。结论　在中国汉族人群 中GRIK2基因或邻近基因可能是精神分裂症和心境障碍的共同易患基因之一,并可能影响发病年龄。     

隐花色素-1基因与精神分裂症核心家系的传递不平衡分析

目的探讨精神分裂症与隐花色素-1（Cryl）基因多态性的关联关系。方法应用聚合酶链反应和限制性片段长度多态性技术对100个精神分裂症核心家系的Cryl基因上的多态性位点rs2300448、rs1921135和rs1056560进行多态性检测；用Genehunter2．1软件包进行传递不平衡分析（TDT），并构建可能的单体型。结果（1）rs2300448多态性位点等位基因G和等位基因A传递给患病子女的频率差异有统计学意义，等位基因G优先传递给患病子女（X^2=4．92，P=0．027），但P值经Bonferroni校正后，差异无统计学意义（Pc=0．054）；rs1056560和rs1921135多态性位点未发现传递不平衡现象（X^2=0．15，P=0．698；X^2=0．56，P=0．456）。（2）单体型rs2300448-rs1056560G—A（X^2=6．76，P=0．009）、rs1921135-rs2300448-rs1056560T—G—C（X^2=4．50，P=0．034）和C—G—A（X^2=6．37，P=0．012）存在传递不平衡现象，但P值经Bonferroni校正后，T—G—C和C—G—A差异均无统计学意义（Pc〉0．05），只有单体型rs2300448-rs1056560G—A差异有统计学意义（Pc=0．036）。结论Cry1基因可能与精神分裂症相关联。     

硫氧还原蛋白结合蛋白基因多态性与精神分裂症的关联分析

目的探索硫氧还原蛋白结合蛋白（TXNIP）基因与精神分裂症的关联关系。方法以182个精神分裂症核心家系为研究对象，应用聚合酶链反应和限制性片段长度多态性技术（PCR-RFLP）对TXNIP基因标签单核苷酸多态性（htSNP）rs9245进行基因分型；使用传递不平衡（TDT）、基于单体型的单体型相对危险度分析（HHRR）检测TXNIP基因与精神分裂症之间的关联关系。结果①患者组、父母组htSNP rs9245位点各基因型的分布均符合Hardy-Weinberg平衡法则（矿值分别为0．68，0．02，df=1，P〉0．05）；②单体型相对风险分析（HHRR）显示htSNP rs9245位点等位基因在患者组和父母组的频数分布为χ^2=3．42，P=0．064；③传递不平衡检验（TDT）分析显示，杂合子父母传递给受累子女与非传递等位基因频率分布为χ^2=3．40，P=0．065，虽然差异未达到显著性，但接近边缘显著性。结论本研究虽未发现TXNIP基因htSNP rs9245与精神分裂症的发生存在关联，但不能排除两者的阳性关联，尚需选择更多SNP及扩大样本量进一步分析。     

α7-烟碱样乙酰胆碱受体基因rs1042724多态性与精神分裂症的关联研究

目的研究α7-烟碱样乙酰胆碱受体基因rs1042724多态性与精神分裂症的相关性。方法运用聚合酶链反应扩增及单核苷酸多态性的分子生物学技术,对符合精神分裂症诊断标准的98个先证者及其父母组成的核心家系,测定α7-烟碱样乙酰胆碱受体基因分型,进行精神分裂症的α7-烟碱样乙酰胆碱受体基因多态性的关联分析和传递不平衡(TDT)检验。结果TDT检验结果提示α7-烟碱样乙酰胆碱受体基因等位基因与精神分裂症之间的相关性(McNemarχ2=4.21,P<0.05),且等位基因T携带者,其精神分裂症的易患性是C携带者的1.31倍(RR=1.31,χ2(RR)=3.96,P<0.05)。结论提示α7-烟碱样乙酰胆碱受体基因rs1042724与精神分裂症相关联。     

精神分裂症和心境障碍混合家系5-HTR 6基因多态性的关联分析

目的 在中国汉族人群精神分裂症和心境障碍混合家系中探讨五羟色胺6受体（5-HTR6）基因267C／T多态性与精神分裂症、心境障碍的关联性。方法 采用聚合酶链反应一限制性片断长度多态（PCR—RFLP）技术对67例精神病混合家系患者及其父母进行5-HTR6基因267C／T多态性检测,并予以传递不平衡检验（TDT）。结果 患者组与父母组之间,5-HTR6基因267C／T多态性等位基因分布（χ^2=2．70,v=1,P〉0．05）和基因型分布（χ^2=2．97,v=2,P〉0．05）无明显差异,5-HTR6基因267C／T多态性与精神分裂症（χ^2=5．16,P〈0．05）存在关联,但与心境障碍（χ^2=2．17,P〉0．05）无关联。结论 在中国汉族人群中5-HTR6基因或邻近基因可能是精神分裂症易患基因之一,但可能不是心境障碍的易患基因。     

精神分裂症与Xp11区HSU93305基因座的单体型及22 q11～13区相关基因的关联性研究

目的探讨Xp11区HSU93305基因座单体型、22 q11～13区α2肾上腺素能受体(A2αR)基因和儿茶酚-氧-甲基转移酶(COMT)基因多态性与精神分裂症的关联.方法分别提取59个中国汉族核心家系成员(母59名,父56名,精神分裂症患者59例)的DNA,采用基因扩增和限制性片段长度多态性技术,进行HSU93305基因座的单体型研究;选择其中56个父母均存活的家系进行A2αR基因和COMT基因多态性传递不平衡检验(TDT)的研究,并应用复等位基因TDT、基于单体型的单体型相对风险率(HHRR)检验等.结果 (1)Xp11区HSU93305基因座经Msp Ⅰ及Dra Ⅱ酶切后产生四种单体型D1M1,D1M2,D2M1,D2M2.父母组以单体型D2M1频率最高(57.7%);患者组也以D2M1传递率最高(59.0%),其次为D1M2(28.9%),D2M2传递率最低(1.2%).(2)经复等位基因TDT分析,精神分裂症与Xp11区HSU93305基因座相关联(χ2=9.28,v=3,P<0.05);与A2αR基因(χ2=1.09,v=1,P>0.05)和COMT基因(χ2=0.31,v=1,P>0.05)未见关联.(3)经HHRR检验,A2αR基因(χ2=1.21,v=1,P>0.05)和COMT基因(χ2=0.37,v=1,P>0.05)与精神分裂症亦未见关联.结论精神分裂症与HSU93305基因座相关联,其易感基因可能位于Xp11区;与A2αR基因和COMT基因多态性可能无关.     

早发性精神分裂症核心家系的亚甲基四氢叶酸还原酶基因传递不平衡研究

目的:在中国汉族早发性精神分裂症家系中探讨亚甲基四氢叶酸还原酶(MTHFR)基因与精神分裂症的相关性。方法:采用聚合酶链反应-限制性片段长度多态性方法(PCR-RFLP)技术,检验111个早发性精神分裂症核心家系MTHFR基因A1298C和C677T多态性,并进行连锁不平衡检验(LD)以及传递不平衡检验(TDT)。结果:A1298C及C677T等位基因在父母与先证者间传递差异均无统计学意义(χ2=0.216,P=0.642;χ2=0.143;P=0.706);连锁不平衡检验表明A1298C与C677T之间存在中度连锁不平衡(D'=0.529);单体型TDT显示早发性精神分裂症核心家系中各单体型传递差异均无统计学意义(P>0.05)。结论:MTHFR基因A1298C及C677T多态性与早发性精神分裂症无明显关联。     

生物钟基因隐花色素-1与精神分裂症核心家系的单体型相对风险分析

目的探讨精神分裂症与生物钟基因隐花色素-1(Cryptochrome-1,Cry1)的关系。方法检测100个精神分裂症核心家系的Cry1基因上的rs2300448-rs1921135和rs1056560三个多态性位点,并进行单体型相对风险分析(HHRR)。结果HHRR结果显示,rs2300448多态性由父母传递给患病子女的等位基因(G/A)频率差异有统计学意义(P<0.05),等位基因G优先传递给患病子女;而rs1056560和rs1921135的等位基因传递频率差异无统计学意义(P>0.05)。结论Cry1基因可能与中国汉族精神分裂症相关联。     

精神分裂症和心境障碍混合家系MLC1基因多态性的关联研究

目的在中国汉族人群精神分裂症和心境障碍混合家系中探讨位于22q13的MLC1基因多态性(rs11568171、rs2076137及rs2235349)与精神分裂症、心境障碍的关系。方法在有精神分裂症和心境障碍混合遗传家族史的67个核心家系(包括44个完整的核心家系)中,采用聚合酶链式反应和限制性片断长度多态性(PCR-RFLP)方法,分析MLC1基因上述多态性的基因型及其单体型,进行传递不平衡检验(TDT)。结果患者组与父母组之间,MLC1基因rs11568171T/C、rs2076137T/C及rs2235349T/C多态性等位基因和基因型分布差异无统计学意义(P>0.05),且TDT结果示各多态性在精神分裂症或心境障碍组中父母与患者之间等位基因传递差异均无统计学意义(P>0.05)。单体型TDT显示,精神分裂症患者组中父母与患者之间单体型T-C-T明显传递过少(2=5.0,P<0.05),而单体型C-C-C明显传递过多(2=5.0,P<0.05)。结论在中国汉族人群中MLC1基因可能是精神分裂症的易感基因,但可能不是心境障碍的易感基因。     

Diagnostic Difficulties and Treatment Implications

Summary: Differentiation between types of epileptic seizures has been aided in recent years by the introduction of intensive neurodiagnostic techniques and the development of increasingly detailed classification systems. Paradoxically, these developments have not simplified the task of matching the appropriate antiepileptic drug to a particular seizure type. It is reasonable to assume that anticonvulsant drugs will have different effects on different types of seizures, but faulty, circular reasoning can enter the picture if one also assumes that responses of seizures to different drugs signify different seizure types. There are several examples of differential diagnoses that can fall prey to this problem, including the diagnosis between partial seizures with secondary generalization and generalized tonic-clonic seizures, and the diagnosis between complex partial seizures and absence seizures with automatisms, among others. Considerations of etiology in future classification systems can further complicate the problem: should one then choose an anticonvulsant drug on the basis of individual seizure type or on the basis of the type of epilepsy? Ramifications of this issue extend even to the drug approval process. Official sanction is not given for use of a drug for a seizure type not included in the original efficacy studies, even if later scientific evidence shows that seizure type to be related to a type that is included. New trials must be undertaken. These problems arise from how we choose to classify seizures.     

Cognitive Dysfunction Associated with Antiepileptic Drug Therapy

Summary: Epilepsy is frequently associated with cognitive dysfunction. However, the reasons for this correlation are unclear. Possible influential factors include patient age; duration, frequency, etiology, and type of seizures; hereditary factors; psychosocial issues; and antiepileptic drug (AED) therapy. Whereas many of these factors are beyond the physician's control, AED therapy is one element that can be addressed in treatment decisions by recognizing the potential cognitive effects of particular AEDs. For example, phenobarbital impairs memory and concentration; phenytoin affects attention, problem solving ability, and performance of visuomotor tasks. In contrast, carbamazepine may affect concentration, while valproate would appear to have minimal effects on cognition. Moreover, cognitive effects of AEDs are amplified with coadministration of multiple anticonvulsants (polytherapy). A review of studies on the cognitive effects of monotherapy with AEDs, as opposed to those of polytherapy, provides evidence that drug-related cognitive dysfunction can be reversed if patients are switched to a simpler therapeutic regimen. Future research should be directed toward developing reliable measures for assessing and monitoring cognition, and understanding the particular cognitive side effects of each AED. Physicians also need to revise their opinions about which side effects are "tolerable" for epileptic patients.     

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.     

Carbamazepine Efficacy in Adults With Partial and Generalized Tonic-Clonic Seizures

Summary: Carbamazepine and phenytoin are drugs of choice in initial monotherapy for adult partial and secondarily generalized tonic-clonic seizures. These designations reflect the results of the Veterans Administration Epilepsy Cooperative Study Group of 1985. An earlier comparative study of carbamazepine and phenytoin by Ramsay and associates found both drugs equally effective in controlling new-onset seizures. Among the advantages of carbamazepine is that it causes relatively few cognitive and dysmorphic side effects. Its disadvantages are its unavailability in parenteral formulation and its metabolic autoinduction. The latter must be compensated for by planned dosage increases to maintain therapeutic plasma steady-state levels during the first 2 or 3 months of treatment. Carbamazepine is judged a drug of choice in the treatment of these secondarily generalized tonic-clonic seizures, and the drug of choice in children, adolescents, and women susceptible to the dysmorphic side effects associated with other anticonvulsant agents.     

Etiologic and Preventive Aspects of Epilepsy in the Child–Bridging the Gap Between Laboratory and Clinic

Summary: Four broad categories of basic phenomena are pertinent to developing ways to prevent epilepsy. These include mechanisms of epileptogenesis, ictal initiation and temporary entrainment by the seizure discharge of normally functioning brain, seizure propagation, and control mechanisms that function both to restrain the cascade of epileptic events culminating in a seizure and to arrest the epileptic event and restore the interictal state. In newborns and children, hypoxia-ischemia is a major factor leading to epileptogenesis, and several schemes are proposed to classify, quantify, and prevent hypoxic-ischemic encephalopathy. Control mechanisms must be better understood in order to develop prophylactic recommendations for epilepsy, and an experimental model of "kindling antagonism" may increase our understanding of these. Programs of prevention of seizures in children will evolve only if basic researchers and clinicians work productively together to develop an adequate understanding of factors important in epileptogenesis and antiepileptogenic control mechanisms.     

Predisposing and Causative Factors in Childhood Epilepsy

Summary: We review information from large studies of defined populations, examining the role of known factors and especially of prenatal and perinatal factors in contributing to nonfebrile seizure disorders of early childhood. We depend especially, but not exclusively, on the recently completed analyses from the Collaborative Perinatal Project of the National Institute of Neurological and Communicative Disorders and Stroke, the NCPP. About 4% of children in the NCPP who had at least one non-febrile nonsymptomatic seizure by the age of 7 years had a previous seizure during acute neurologic illness, such as meningitis or during the acute illness after trauma. Many such seizures should potentially be preventable. Of children with seizures, 10% had had a neonatal seizure and 13% had had a febrile seizure. Among the hundreds of prenatal and perinatal factors explored as predictors of childhood seizure disorders, the principal predictors identified were congenital malformations of the fetus, cerebral and noncerebral; family history of certain neurologic disorders; and neonatal seizures. In agreement with the British National Child Development Study, labor and delivery factors in the NCPP appeared to contribute very little to childhood seizure disorders. Maldevelopment, rather than damage at birth to an initially intact nervous system, appeared to be the more common mechanism. Most seizure disorders of early childhood remained unexplained by the large set of prenatal and perinatal characteristics examined.     

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.     

Treatment Considerations in Anticonvulsant Monotherapy

Summary: The long-standing practice of polypharmacy in treating epilepsy is giving way to use of monotherapy. Monotherapy can improve seizure control as well as reduce the risk of serious idiosyncratic reactions, dose-related side effects, and complex drug interactions. Monotherapy also offers improved compliance and cost-effectiveness. The basis of monotherapy is accurate diagnosis and assessment of the patient's seizure type(s), followed by selection of a single appropriate anticonvulsant drug. Many patients currently treated with multiple anticonvulsants can be successfully converted to monotherapy with a carefully monitored program in which troublesome and redundant drugs are gradually withdrawn from the therapeutic regimen.     

Anticonvulsant Drugs and Cognitive Function: A Review of the Literature

Summary: Alterations of cognitive function are separate from disturbances of behavior seen in association with epilepsy. The nature of the cognitive disability may to a certain extent depend on the seizure type. Partial seizures, mainly derived from a temporal lobe focus, impair memory tasks, while generalized seizures seem to have more effect on attentional abilities. A number of studies, reviewed in this paper, suggest that anticonvulsant drugs further impair cognitive function. Maximal impairments are seen in patients receiving polytherapy: rationalization of polytherapy improves cognitive abilities. Studies in children and adults have allowed differentiation of the effects of various commonly used antiepileptic agents. Maximal cognitive deficits are seen with. phenytoin, while phenobarbital and sodium valproate induce moderate disturbances, and carbamazepine seems relatively free from such toxicity. Further research is needed on the interrelationship between types of seizure disorders, types of anticonvulsant medications, and cognitive function.     

Dextromethorphan: Cellular Effects Reducing Neuronal Hyperactivity

Summary: Dextromethorphan is a dextrorotary morphinan without affinity for opioid receptors, commonly used as an antitussive medication. During the past 5 years, interest in the compound and its demethylated derivative, dextrorphan, has been revived because additional neuroprotective and an-tiepileptic properties were found in in vitro studies, animal experiments, and a few clinical cases. Both morphinans are able to inhibit N -methyl-D-aspartate (NMDA) receptor channels and voltage-operated calcium and sodium channels with different potencies. The inhibition of the NMDA receptor is believed to be the predominant mechanism of action responsible for the anticonvulsant and neuroprotective properties of the compounds.