固定剂对细胞色素氧化酶组织化学染色的影响

细胞色素氧化酶 (CytochromeOxidase ,CO)是呼吸链上的最后一个酶 ,是细胞能量产生和传递的关键组成部分。在中枢神经系统中 ,区域性CO活性反映了局部组织能量代谢变化 ,这种变化与神经元的功能尤其是神经元突触和自发性电活动的能量需求密切相关。CO的组织化学染色方法已被广泛用于反映中枢神经系统CO的活性。为了成功地进行CO的组织化学染色 ,适中的组织固定是关键。固定剂的组成必须考虑既要保持良好的组织结构又要保持较高的酶活性。通常使用多聚甲醛和戊二醛混合固定液。本实验选用不同浓度的多聚甲醛和戊二醛固定组织 ,做CO组织化学染色 ,并进行光镜和电镜观察 ,发现 1%多聚甲醛和 2 %戊二醛混合固定既可保存良好的组织结构又可获得较高的CO活性。     

细胞色素氧化酶与脑功能研究

细胞色素氧化酶（ｃｙｔｏｃｈｒｏｍｅｏｘｉｄａｓｅ,ＣＯ）作为电子传递链的末端酶,是神经元活动的内源性代谢指标之一。在正常功能状态下,细胞色素氧化酶活性从细胞器到系统各水平都表现出很强的不一致性,并随神经元功能状态的改变其活性随着发生变化。眼优势柱研究的诸多进展及视通路的研究与细胞色素氧化酶组织化学技术的应用是分不开的。许多神经变性疾病均伴有细胞色素氧化酶的缺陷。用于细胞色素氧化酶研究的方法日渐增多。目前大多数中枢神经系统水平的研究均采用组织和细胞化学方法。基因水平的研究已经开展,杂交探针可揭示亚基ｍＲＮＡ水平的变化。与２－脱氧葡萄糖放射自显影相比,细胞色素氧化酶组织化学反映是一个能量代谢更稳定的状态。利用近红外光谱可对细胞色素氧化酶氧化还原状态的变化进行无创性研究。     

伴神经毡岛样结构的胶质神经元肿瘤:一例报告并文献复习

目的 探讨伴神经毡岛样结构的胶质神经元肿瘤的病理学特征.方法 1例右侧顶枕部和胼胝体伴神经毡岛样结构的胶质神经元肿瘤(WHOⅡ～Ⅲ级)患者,HE染色和免疫组织化学染色行组织形态学观察和病理分析,并复习相关文献.结果 大体标本观察肿瘤为灰白色破碎组织块,质地柔软,约3.00 cm×3.00 cm×0.50 cm大小.组织形态学观察,肿瘤细胞里界限分明的两种排列.一种为部分细胞呈圆形和卵圆形,异型性不明显,核分裂象少见,局部血管内皮细胞增生;部分细胞呈菊心团样结构,中心为神经毡岛样结构,肿瘤细胞呈广泛的"假栅栏状"排列,中心为神经毡岛样结构.另一种为肿瘤细胞呈"旋涡状"排列.伴钙化.免疫组织化学染色显示,神经毡岛样结构区域巢蛋白强阳性表达,神经元核抗原表达阴性,神经毡岛样结构周围部分细胞少突胶质细胞转录因子-2表达阳性,中心部化突触素强阳性表达;星形细胞瘤区域胶质纤维酸性蛋白表达阳性,p53阳性细胞数日为25%～50%;神经毡岛样结构区域Ki-67抗原标记指数<5%,星形细胞瘤区域约为10%.结论 伴神经毡岛样结构的胶质神经元肿瘤的生物学行为与浸润件星形细胞瘤相似,但"假栅栏状"结构与文献报道略有不同,可能与多个神经毡岛样结构融合有关.肿瘤染色体榆测与星形细胞瘤相似,均表现为染色体7q、9p缺失,提示其本质-生物学行为仍为星形细胞源性而非神经无源性肿瘤.     

一氧化氮及其合成酶与脑创伤性损害

一氧化氮(NO)是一种具有生物活性作用的小分子,它分布于人体多种组织中。NO内源合成的关键酶是一氧化氮合成酶(NOS)。脑损伤能诱导局部神经元和传入到损伤区域的神经元表达NOS,伤口内反应性的星形细胞和相关的胶质细胞聚集并有较高的NOS活性。NO发挥神经毒性作用的中心环节是损伤DNA,使细胞内能量储备耗竭而引起细胞死亡。     

中枢神经细胞瘤的组织学及免疫组织化学研究

目的对中枢神经细胞瘤进行组织学及免疫组织化学研究,探讨细胞分化、组织发生及增殖潜能.方法对37例中枢神经细胞瘤进行HE染色及6种抗体的免疫组织化学染色,光镜下观察.结果血管增生19例,坏死6例,出血27例,核分裂23例,25例可找到神经元;Synaptophysin和NSE37例阳性,GFAP10例偶见细胞及纤维阳性,ChromograininA和NF全部阴性,PCNA-LI1.95±1.77,从0到9.95%.结论神经细胞具有进一步分化为神经元和胶质细胞的能力;肿瘤可能来源于胚胎残余原始神经上皮细胞;核分裂阴性病例的PCNA-LI＜1%,核分裂阳性的病例(除2例外)PCNA-LI＞1%,P=0.000008,提示核分裂阳性的中枢神经细胞瘤较核分裂阴性肿瘤增殖倾向活跃.     

胚胎发育不良性神经上皮肿瘤临床病理分析(附5例报告)

目的探讨胚胎发育不良性神经上皮肿瘤(DNT)的临床病理特征、影像学特点、治疗及预后。方法应用光镜及免疫组织化学染色对5例DNT进行观察分析。结果主要临床症状为顽固性癫痫发作,神经系统检查无阳性体征。MRI病变呈囊实性改变,无强化、无瘤周水肿及占位效应。肿瘤组织形态类似,由神经胶质-神经元成分构成,周围有少突胶质细胞样细胞(OLC),其组织学特点是瘤组织黏液变明显,多见网状微囊变,单个神经元漂浮在微囊的黏液样基质中。免疫组织化学染色示神经元及部分OLC突触素、神经核抗原(NeuN)及S-100阳性,OLC胶质纤维酸性蛋白染色阴性,Ki-67低增殖活性。4例随访2~7年,术后均无复发。结论 DNT属良性肿瘤(WHOⅠ级),手术切除即可治愈。结合临床表现、影像学及病理形态学和免疫组织化学结果DNT才确诊。     

脑梗死后细胞骨架和暗神经元的变化

目的　通过研究细胞骨架的变化 ,探讨脑梗死后神经元及暗神经元损伤的程度。方法7例尸检梗死脑做全脑大切片染色后 ,将梗死及其周围分成 4个区 (0～ 3区 ) ,各区取小块组织 ,用组织化学和免疫组织化学的方法观察梗死脑的暗神经元、微管相关蛋白 (MAP2 )、相对分子质量为2 0 0 0 0 0的神经丝 (NF2 0 0 )和星形细胞中的胶质纤维酸性蛋白 (GFAP) ,认识暗神经元、细胞骨架与梗死病理过程之间的关系 ,并进行病灶内外及其与对侧脑组织细胞骨架变化的对比。结果　 1区暗神经元约为 90 % ;2区为 40 %～ 5 0 % ,有些暗细胞伴有细胞骨架的严重变化 ,有的细胞骨架显色正常 ,少数FAS染色阳性 ,末端脱氧核苷酸转移酶介导DUPT的缺口末端描记法 (TUNEL法 )全部阴性。 0区MAP2和NF2 0 0消失 ,1区MAP2和NF2 0 0显著异常 ,提示为不可逆的缺血损伤 ;2区MAP2和NF2 0 0有轻度改变 ,提示损伤可能为可逆性 ;3区细胞骨架正常而星形细胞增生明显 ,表明为损伤反应。结论暗神经元是脑缺血后的主要神经元变化形式之一 ,少数处于凋亡早期 ,多数则尚未凋亡。缺血细胞骨架损伤轻者 ,神经细胞功能有可能恢复 ;损伤重者 ,神经细胞功能不能恢复     

组织工程脊髓移植治疗大鼠脊髓半切块状损伤

目的 研究组织工程脊髓移植治疗大鼠脊髓半切块状损伤的疗效.方法 以聚乳酸-羟基乙酸(PLGA)为细胞支架,多聚赖氨酸为细胞外基质,神经十细胞(NSCs)为种子细胞,体外构建组织工程脊髓.制作大鼠T10脊髓右半切块状损伤模型,随机分成3组:实验组在损伤区移植组织工程脊髓,对照组A移植NSCs,对照组B移植PLGA.移植治疗12周,每周均行BBB评分定量评价肢体运动功能.伤后第12周辣根过氧化物酶(HRP)神经逆行示踪评价脊髓传导束的恢复程度,并取损伤处脊髓组织行免疫组织化学染色,观察移植区的形态结构修复.结果 伤后12周实验组的BBB运动功能评分较对照组明显提高,差异有统计学意义(P＜0.05).HRP神经逆行示踪显示:实验组鼠右侧大脑组织中可见大量的HRP标记阳性神经元,而两对照组仅见有少量HRP阳性神经元;免疫组织化学染色显示:实验组移植区NF阳性神经元和GAP-43阳性神经轴索数量较多,修复了缺损,而对照组极少,仍留下不同程度的缺损.结论 组织工程脊髓移植治疗促进了半切块状损伤脊髓的形态结构修复和功能恢复,疗效明显优于单纯的NSCs移植和PLGA移植.     

嗅鞘细胞对培养脊髓神经元生长状态的影响

目的研究嗅鞘细胞(OECs)对体外培养脊髓背根神经节神经元生长状态的影响。方法取新生大鼠脊髓背根神经节细胞与嗅鞘细胞共培养,在显微镜下观察神经元生长发育情况,染色后进行细胞计数,并测定细胞活性。结果共培养组细胞密度明显高于对照组,神经元胞体大而饱满,突起较长,细胞活性较高。结论嗅鞘细胞可明显促进体外培养脊髓背根神经节神经元的生长,提高细胞活性。     

中枢神经系统肠源性囊肿的形态及免疫组化研究

目的：观察中枢神经系统肠源性囊肿的组织形态及免疫组织化学特征。方法：使用病理组织学及免疫组织化学方法对３１例中枢神经系统不同部位的肠源性囊肿进行研究。结果：囊肿壁上皮可为单层或复层扁平、立方、柱状上皮；一些病例可见两种以上上皮组织成分，并相互移行；某些病例，在囊肿壁内可含有黑色素、软骨、平滑肌、粘液腺等多种组织成分。免疫组织化学染色ＥＭＡ均呈阳性；ＣＥＡ染色仅一例阴性，而此例ＮＳＥ阳性，故应诊断为神经上皮性囊肿；Ｓ－１００和ＣＫ染色结果不固定；Ｖｉ－ｍｅｎｔｉｎ和ＧＦＡＰ均呈阴性。结论：肠源性囊肿的组织形态和免疫组织化学特点可作为鉴别其他类型囊肿的依据。     

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.