人脑组织匀浆液诱导大鼠骨髓间质干细胞分化为神经细胞

目的 研究人脑组织匀浆液诱导大鼠骨髓间质干细胞向神经元细胞分化能力。方法从大鼠骨髓分离培养骨髓间质干细胞．经体外增殖，用人脑组织匀浆液诱导骨髓间质干细胞向神经元样细胞分化，应用免疫细胞化学方法对分化的细胞进行鉴定。结果大鼠骨髓间质干细胞可在体外增殖，经人脑组织匀浆液诱导，骨髓间质干细胞可向神经元样细胞分化，且分化率较高，24小时为45％，48小时为78．2％，72小时为88．3％。分化后的细胞表达神经元标志物-神经微丝(NF)和神经元特异性烯醇化酶(NSE)。结论人脑组织匀浆液可诱导大鼠骨髓间质干细胞向神经元细胞分化，从而为骨髓间质干细胞脑内移植与及其分化，以及神经功能的修复提供了基础。     

损伤脑组织匀浆诱导骨髓间质干细胞向神经细胞分化的研究

目的探讨损伤脑组织匀浆液对骨髓间质干细胞的诱导分化作用。方法体外分离、培养骨髓间质干细胞,经体外增殖,用损伤脑组织匀浆液诱导其分化,应用免疫细胞化学方法对分化的细胞进行鉴定。结果大鼠骨髓间质干细胞可在体外增殖,经损伤脑组织匀浆液诱导,骨髓间质干细胞形态学改变明显,部分细胞突起可见锥样改变,在细胞密集处可突起交织成网。免疫细胞化学法染色显示分化细胞呈NSE阳性表达占23.2%±6.09%,GFAP阳性表达占14.3%±3.27%。结论损伤脑组织匀浆液可诱导大鼠骨髓间质干细胞向神经细胞分化,部分为神经元,部分为神经胶质细胞。     

人骨髓间充质干细胞体外定向诱导分化为神经元样细胞

背景：文献报道体外诱导骨髓间充质细胞定向分化为神经元样细胞多应用神经生长因子类多肽制剂,选择纯化学诱导剂尚不多见。 目的：建立人骨髓间充质干细胞分离培养体系,体外定向诱导人骨髓间充质干细胞分化为神经元样细胞。 方法：密度梯度离心、贴壁培养法和消化时间控制相结合分离纯化人骨髓间充质干细胞并鉴定,采用β-巯基乙醇和二甲基亚砜诱导分化为神经元样细胞,观察细胞形态,通过尼氏染色、NSE和NF-200免疫细胞化学染色对已分化的神经元样细胞进行鉴定和分化率分析。 结果与结论：分离得到的骨髓间充质干细胞为成纤维样细胞,可见多个核仁,β-巯基乙醇和二甲基亚砜诱导后,间充质干细胞分化为神经元样细胞,伸出较长轴突样和树突样突起且有分支,诱导后的神经元样细胞胞质中存在着深蓝色颗粒状的尼氏小体,NSE、NF-200免疫荧光细胞化学染色均呈阳性,阳性率分别为(85.6±6.7)%和(73.2±5.6)%。结果证实采用密度梯度离心、贴壁培养法和消化时间控制相结合能够成功分离和培养人骨髓间充质干细胞,人骨髓间充质干细胞能够在诱导剂β-巯基乙醇和二甲基亚砜的诱导下体外诱导分化为神经元样细胞。     

恒河猴骨髓基质细胞向成熟神经细胞分化的实验研究

目的研究恒河猴骨髓基质细胞(BMSCs)在体外向神经细胞诱导分化过程中神经递质分泌和神经细胞抗原表型表达情况。方法无菌条件下密度梯度法分离猴BMSCs,在体外应用神经干细胞培养液进行体外培养和诱导分化,分阶段用高效液相色谱法检测培养基中单胺类生物活性物质的含量,免疫细胞化学方法检测神经细胞抗原表型。结果高效液相检测神经干细胞培养基未测到单胺类生物活性物质,而经体外培养增殖10d、14d、30d的细胞培养基可检测到去甲肾上腺素 (NE)和多巴胺(DA)。Asp方差分析显示:随着BMSCs培养天数的增加,培养基中所含的NE和DA尤显著性差异(P>0．05)。同期细胞免疫组化检测出酪氨酸羟化酶(TH)、巢蛋白抗体(nestin)、β-微管蛋白 (β-tublin)、胶质原性纤维酸性蛋白抗体(GFALP)和神经元特异烯醇化酶(NSE)抗原表达。结论恒河猴BMSCs能在体外增殖,在适宜条件下能分化成神经元样细胞,并合成、分泌NE和DA;部分细胞表达神经干细胞、成熟神经元、胶质细胞和DA能神经元的抗原表型,提示在一定条件下,诱导分化的 BMSCs经过神经干细胞阶段可向成熟神经组织细胞分化。     

人骨髓间质干细胞的分离培养和诱导分化为神经元样细胞的研究

目的:探索成人骨髓间充质干细胞(MSCs)的分离培养及诱导分化为神经元样细胞的体外条件。方法:采用Ficoll淋巴细胞分离液(1.077g·mL-1)密度梯度离心法从人的骨髓中分离出MSCs进行体外扩增。收集第2代细胞流式细胞仪检测MSCs表面标志。逐渐加入表皮生长因子(EGF)、β-巯基乙醇(BME)和全反式维甲酸(ATRA)诱导MSCs向神经元细胞分化,通过免疫细胞化学法鉴定诱导后细胞神经元烯醇化酶(NSE)、神经巢蛋白(nsetin)、胶质纤维酸性蛋白(GFAP)的表达情况。结果:流式细胞仪检测结果显示培养后的MSCs强表达CD29;较强表达CD44、CD166和CD105;不表达CD45、CD34和HLA-DR。诱导剂诱导后,MSCs分化为具有典型的神经元形态的细胞,免疫细胞化学显示78%的细胞NSE表达阳性;大约51%细胞nsetin表达阳性;所有细胞GFAP均阴性表达。结论:成人MSCs在体外可定向诱导分化为神经元样细胞,且具有较高的阳性分化率。     

体外定向诱导人骨髓基质细胞分化为神经元样细胞三种方法的比较

目的观察比较不同的体外定向诱导培养方法对人骨髓基质细胞(骨髓间充质干细胞)分化为神经元样细胞的影响。方法分离、扩增培养人骨髓基质细胞,分别采用人重组纤维母细胞生长因子(FGF-2)和人重组脑源性神经营养因子(BDNF)、2-巯基乙醇(2-ME)以及硫代甘油(TG)等3种不同的诱导剂,诱导骨髓基质细胞分化为神经元样细胞。用神经元特异性烯醇化酶(NSE)和胶质纤维酸性蛋白(GFAP)免疫组织化学方法对已分化的神经元样细胞进行鉴定和分化率分析。结果经3种诱导剂诱导的人骨髓基质细胞均出现神经元样细胞的分化,胞体呈神经元状,伸出较长轴突样和树突样突起且有分支。免疫组化鉴定显示,诱导分化后的神经元样细胞NSE染色呈阳性,GFAP免疫组化染色均呈阴性,其中FGF-2+BDNF诱导组神经元样细胞分化率为(68.220±5.743)%;2-ME诱导组为(50.700±3.374)%;TG诱导组为(32.240±3.800)%,3组之间差异具有显著性意义(P<0.05)。结论人骨髓基质细胞能够在诱导剂的诱导下发挥横向分化能力,3种体外诱导培养方法均可诱导人骨髓基质细胞分化为神经元样细胞。     

猫骨髓基质细胞诱导为神经干细胞的实验研究

目的观察猫骨髓基质细胞体外培养及诱导分化情况。方法从猫的骨髓中分离得到骨髓基质细胞(Bone Marrow Stromal cells．BMSC），在体外给予神经干细胞培养基培养，增殖后用分化诱导因子(维甲酸，Retinoic acid，RA)进行诱导分化．倒置相差显微镜下观察活细胞及免疫细胞化学染色情况。结果猫骨髓基质细胞在体外培养中胞体增大，镜下可见丰富的胞浆颗粒，继之出芽，贴壁生长，可形成克隆团，同时可传代培养。这些具有克隆能力的骨髓基质细胞能表达神经干细胞特异性抗原nestin，而且能分化出胶质细胞样细胞和神经元样细胞。结论猫骨髓基质细胞具有干细胞特征，在合适的条件下可扩增、形成克隆并诱导分化出神经胶质细胞和神经元特征细胞，它们可考虑作为神经系统功能缺失细胞移植治疗的种子细胞来源。     

体外诱导大鼠骨髓间质干细胞分化为神经样细胞的实验研究

目的 探讨在体外诱导骨髓间质干细胞(MSCs)分化为神经样细胞的可行性。方法 采用Percoll(1．077g／L)离心分离MSCs，然后进行培养，以流式细胞仪进行荧光三标检测．并用免疫细胞化学法鉴定经β-巯基乙醇(BME)、二甲亚砜(DMSO)、丁羟茴醚(BHA)诱导分化的细胞是否为神经样细胞。结果 分离后的MSCs在生长因子的作用下出现增殖性生长．经流式细胞仪检测显示CD90和CD106阳性、CD45阴性，经诱导后MSCs分化的细胞经免疫细胞化学证实巢蛋白(nestin)、神经元特异性核蛋白(NeuN)、胶质纤维酸性蛋白(GFAP)、2-3-环核苷酸磷酸二脂酶(CNP)阳性。结论 MSCs经诱导可分化为神经样细胞。     

人骨髓间充质干细胞的体外培养及睫状神经节神经营养因子诱导其向神经元样细胞分化的研究

目的 探讨人骨髓间充质干细胞(h-MSCs)体外培养条件及睫状神经节神经营养因子(CNTF)对h-MSCs向神经元样细胞分化的影响.方法 采用梯度离心法和全骨髓法相结合,利用含血清的DMEM/F12培养基培养h-MSCs,以碱性成纤维细胞生长因子(bFGF)预诱导24 h后再以不同浓度CNTF诱导,传至第3代时h-MSCs开始向神经元样细胞方向分化.应用免疫细胞化学技术对培养细胞及其分化细胞进行鉴定.结果 h-MSCs在体外培养条件下能保持旺盛的增殖能力,CNTF诱导后细胞形态发生明显改变,伸出突起,类似神经元;免疫细胞化学法检测显示CD44、CD54以及诱导后神经元特异性蛋白(NSE)和巢蛋白(nestin)均呈阳性表达.10 ng/mL 实验组NSE阳性细胞占细胞总数的(42.42±1.39)%,nestin阳性细胞占细胞总数的(45.36±1.60)%.结论 h-MSCs可在体外扩增、培养.h-MSCs经bFGF预诱导后再经CNTF诱导可向神经元样细胞方向分化.10 ng/mL为CNTF的最适诱导浓度.     

成鼠骨髓基质细胞向神经干细胞诱导分化的实验研究

目的研究成鼠骨髓基质细胞体外培养的生长行为和分化情况。方法利用EGF、FGF-b等增殖及分化诱导因子和神经干细胞培养液进行培养,分化诱导,用细胞免疫组化染色进行细胞鉴定。结果成鼠骨髓基质细胞在体外培养中能形成细胞克隆团,具有增殖能力,并可分化出胶质细胞样细胞和神经元样细胞。结论骨髓基质细胞具有较强的自我更新及多向分化能力,在适宜的诱导分化条件下,可诱导为神经干细胞,分化出神经元和胶质细胞。     

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.     

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.     

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.     

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.     

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.