MMP-2及PTEN在人脑星形细胞瘤中的表达及意义

目的探讨基质金属蛋白酶2(MMP-2)及抑癌基因PTEN在人脑星形瘤中的表达及二者与人脑星形细胞瘤侵袭性的关系。方法用免疫组织化学SABC法检测50例人脑星形细胞瘤组织和10例正常人脑组织中的MMP-2和PTEN蛋白的表达,并且分析二者与人脑星形细胞瘤临床病理分级的关系。结果 MMP-2和PTEN在低度恶性星形细胞瘤和高度恶性星形细胞瘤组织中表达差别有统计学意义(p<0.05)。随着星形细胞瘤恶性度增高,MMP-2的表达强度呈上升趋势而PTEN表达强度逐渐下降;Spearman等级相关分析表明人脑星形细胞瘤中MMP-2和PTEN之间呈负相关(Rs=-0.518,P<0.01)。结论 MMP-2和PTEN是人脑星形细胞瘤分化程度和转移的潜在生物学指标,联合检测MMP-2和PTEN更有利于判断星形细胞瘤生物学行为和病理分级。     

Skp2和PTEN在人脑星形细胞瘤中的表达及临床意义

目的探讨Skp2和PTEN在人脑星形细胞瘤中的表达及与病理分级的关系。方法免疫组化S-P法检测70例Ⅰ～Ⅳ级脑星形细胞瘤和8例正常脑组织标本中Skp2和PTEN的表达。结果(1)Skp2、PTEN在人脑星形细胞瘤组中阳性表达率分别为47.1%和50.0%,而在正常脑组织组中阳性表达率分别为0%和100%。从星形细胞瘤I、II级组,III级组到IV级组,Skp2的阳性表达率呈增高趋势,分别为9.1%、45.5%、80.8%,而PTEN的阳性表达率呈降低趋势,分别为90.9%、50.0%、15.4%。(2)Spearman等级相关检验证实病理分级和Skp2标记指数呈正相关,和PTEN标记指数呈负相关。人脑星形细胞瘤中Skp2和PTEN的表达呈负相关。结论Skp2和PTEN蛋白的表达情况可作为人脑星形细胞瘤的诊断和恶性程度评估的参考资料,可能成为人脑星形细胞瘤治疗的新靶点。     

PTEN蛋白和核增殖相关抗原Ki-67在星形细胞瘤中的表达

目的　检测PTEN蛋白和Ki-67(MIB-1)在星形细胞瘤中的表达及相互关系。方法　应用免疫组化结合计算机图像分析方法检测62例星形细胞瘤中PTEN蛋白和Ki-67表达情况。结果　低分化(Ⅲ一Ⅳ级)星形细胞瘤中PTEN蛋白表达显著低于高分化(Ⅰ-Ⅱ级)星形细胞瘤(P<0.001);Ki-67蛋白在不同病理分级的星形细胞瘤中表达差异显著(P<0.01),且星形细胞瘤增殖指数(PI)与PTEN蛋白表达呈负相关(r=-0.778,P<0.001)。结论 PTEN蛋白表达可能在星形细胞瘤细胞增殖中发挥重要作用。     

PTEN/MMAC1基因改变与胶质细胞瘤生物学特征相关性研究

目的探讨胶质瘤PTEN/MMAC1基因突变及缺失与肿瘤分型、病理分级和肿瘤生长部位、患者年龄、性别的关系.方法应用聚合酶链反应-单链构象多态性电泳分析(PCR-SSCP)结合银染技术、双重PCR技术检测80例胶质瘤PTEN/MMAC1基因九个外显子点突变与基因缺失情况.结果 80例胶质瘤分别有15例(18.75%)和27例(33.75%)PTEN/MMAC1基因点突变和基因缺失,且PTEN/MMAC1基因失活与胶质瘤病理分级明显相关(P<0.05),其中低分化胶质瘤(Ⅲ～Ⅳ级)突变率(31.30%)和缺失率(60%)明显高于高分化(Ⅰ～Ⅱ级)胶质瘤(P<0.05).其中,少突胶质细胞瘤仅有1例PTEN/MMAC1基因缺失(7.70%).星形细胞瘤PTEN/MMAC1基因第5外显子、第6外显子和第8外显子是胶质瘤PTEN/MMAC1基因易突变区.PTEN/MMAC1基因失活与患者性别、年龄及肿瘤生长部位无相关性.结论人胶质瘤PTEN/MMAC1基因与病理分级关系密切,不同起源的胶质瘤PTEN/MMAC1基因改变差异明显.     

脑星形细胞瘤癌基因表达

52例星形细胞瘤应用免疫组化方法,检测癌基因p~(53)、C-erbB-2及增殖细胞核抗原(PCNA)的表达,结果发现①p53异常表达率为41.2%(24/52),C-erbB-2过度表达率为39%(20/52),PCNA(PI>0.05)增殖指数为77%(40/52),与对照组正常脑组织对比有显著差异(P<0.001).②p53,C-erbB-2,PCNA异常表达与病理级别有明显相关性.病理Ⅲ,Ⅳ级的阳性率分别为80%(16/20),40%(8/20),100%(20/20),(P0.05);C-erbB-2阳性组,PCNA指数;0.361±0.27,阴性组PCNA指数;0.399±0.39,两组间亦无差异(P>0.05).④11例胶质增生组织有1例(9%)显示p53表达,C-erbB-2,PCNA无表达.随访3年,病变复发,病理证实为星形细胞瘤Ⅰ～Ⅱ级,C-erbB-2,PCNA表达.结果提示:①星形细胞瘤p53、C-erbB-2及PCNA的异常表达可作为星形细胞瘤恶性程度及病人预后的指标,以p53过度表达尤为重要;②3种抗体的联合应用对星形细胞瘤发病机理研究及预测早癌发生有一定价值,p53异常表达主要是影响星形细胞瘤的分化,而C-erbB-2对肿瘤进展早期起一定作用.③胶质增生的胶质细胞具有恶性表型.     

人脑星形细胞瘤PTEN／MMAC1基因突变的研究

目的：了解在人脑星形细胞瘤中PTEN／MMAC基因第五、第八外显子的突变情况及其在肿瘤恶性进展中的作用。方法：应用聚合酶链反应（PCR）、银染PCR－单链构象多态性（SSCP）技术对52例人脑星形细胞瘤，7例正常脑组织和3例外周血标本进行检测。结果：52例病人中8例发生PTEN／MMAC第五、第八外显子点突变，突变率为15．4％（8／52），其中20例病理Ⅰ-Ⅱ级的星形细胞瘤无突变，32例Ⅲ-Ⅳ级的星形细胞瘤中有8例发生点突变，突变率25％（8／32），两相较，相差显（P＜0．05），结论：人脑星形细胞瘤中存在PTEN／MMAC基因第五、第八外显子点突变，这可能是肿瘤恶性进展的重要事件之一。     

LRIG1基因在人星形细胞瘤中的表达与意义

目的探讨LRIG1在人星形细胞瘤中的表达与意义。方法设计、制作LRIG1mRNA寡核苷酸探针,用原位杂交检测LRIG1mRNA在16例不同级别人星形细胞瘤组织及11例原代培养的人脑星形细胞瘤细胞中的表达,同时用免疫组化检测增殖细胞核抗原(PCNA)的表达,分析肿瘤LRIG1表达和PCNA表达之间的关系。结果人星形细胞瘤组织和培养的星形细胞瘤细胞中均有一定程度的LRIG1表达,其表达的程度与PCNA表达呈显著负相关(P<0.05)。结论LRIG1蛋白具有抑制星形细胞瘤增殖的作用,可能参与了肿瘤的发生和发展过程。     

人脑星形胶质细胞瘤中nm23-H1蛋白及PCNA的表达

目的 研究人脑星形胶质细胞瘤中nm23-H1 蛋白和增殖细胞核抗原(PCNA)表达情况及其与患者预后的关系。方法采用免疫组化的方法,对62例人脑星形胶质细胞瘤石蜡切片标本中mn23-H1编码蛋白和PCNA进行检测。结果 62例人脑星形胶质细胞瘤免疫组化结果。Ⅰ级、Ⅱ级中nm23-HI蛋白的表达显著高于Ⅲ、Ⅳ级;Ⅲ、Ⅳ级中PCNA的表达显著高于Ⅰ、Ⅱ级;但PCNA蛋白表达与nm23-H1表达无显著相关性。在34例随访病人中,发现nm23-H1蛋白高表达组及PCNA低表达组的术后生存时间较长。结论nm23-H1蛋白低表达及PCNA高表达与星形胶质细胞瘤的高病理学分级有关。nm23-H1蛋白高表达和PCNA低表达提示较好的临床预后。     

Skp2和PTEN在人脑星形细胞瘤中的表达及临床意义

目的探讨Skp2和PTEN在人脑星形细胞瘤中的表达及与病理分级的关系。方法免疫组化S-P法检测70例Ⅰ～Ⅳ级脑星形细胞瘤和8例正常脑组织标本中Skp2和PTEN的表达。结果（1）Skp2、PTEN在人脑星形细胞瘤组中阳性表达率分别为47．1％和50．0％，而在正常脑组织组中阳性表达率分别为0％和100％。从星形细胞瘤Ⅰ、Ⅱ级组，Ⅲ级组到Ⅳ级组，Skp2的阳性表达率呈增高趋势，分别为9．1％、45．5％、80．8％，而PTEN的阳性表达率呈降低趋势，分别为90．9％、50．0％、15．4％。（2）Spearman等级相关检验证实病理分级和Skp2标记指数呈正相关，和PTEN标记指数呈负相关。人脑星形细胞瘤中Skp2和PTEN的表达呈负相关。结论Skp2和PTEN蛋白的表达情况可作为人脑星形细胞瘤的诊断和恶性程度评估的参考资料，可能成为人脑星形细胞瘤治疗的新靶点。     

PCNA和GFAP在脑星形胶质细胞瘤中表达的双重染色研究

目的研究人脑星形胶质细胞瘤中增殖细胞核抗原（PCNA）和胶质纤维酸性蛋白（GFAP）的表达及其与肿瘤分级的关系。方法采用免疫组化双重染色法对41例人脑星形胶质细胞瘤进行PCNA和GFAP两重标记检测。结果脑星形胶质细胞瘤中PCNA与GFAP表达率均为100％，PCNA表达水平与肿瘤分级呈正相关（r=-0．627，P〈0．01），GFAP表达水平与肿瘤分级呈负相关（r=-0．568，P〈0．01）；Ⅰ-Ⅱ级与Ⅲ-Ⅳ级胶质瘤间PCNA和GFAP表达均有显著性差异（P〈0．05）；GFAP表达和PCNA表达水平呈负相关（r=-0．332，P〈0．05）。结论PCNA与GFAP的表达有一定的相关性。PCNA与GFAP的双重表达与脑星形胶质细胞瘤的增殖活性和恶性程度有关。     

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.     

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.     

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.     

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.     

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.     

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.     

Effects of NMD A- and AMPA-Receptor Antagonists on Different Forms of Epileptiform Activity in Rat Temporal Cortex Slices

Summary: Lowering extracellular magnesium induces different patterns of epileptiform activity in rat hippocampus and entorhinal cortex. Short recurrent epileptiform discharges in the hippocampus are stable over time, whereas seizurelike events (SLEs) in the entorhinal cortex, the subiculum, and the neighboring neocortex develop into late recurrent discharges which are not blocked by clinically employed antiepileptic drugs. We tested the sensitivity of the different epileptiform discharge patterns to. /V-methyl-D-aspartate (NMDA)- and non-NMDA-receptor antagonists. As NMDA-receptor antagonist we used dextrorphan, ket-amine, and 2-aminophosphonovalerate (2APV); as α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA)-receptor antagonist we employed the quinoxaline derivative glutamate 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). The findings show that the different patterns of epileptiform activity, including the late recurrent discharges, are sensitive to all NMDA-receptor antagonists. However, when dextrorphan was employed to suppress seizure-like events, later recurrent discharges did not develop during the remaining time course of the experiment. CNQX reversibly suppressed recurrent discharges in the hippocampus and SLEs in the entorhinal cortex. However, late recurrent discharges become insensitive to CNQX, even at a high concentration of 60 μM m. This finding suggests a prominent role for NMDA receptors in the generation of late recurrent discharges.