大鼠骨髓间质干细胞用中药绞股蓝诱导为神经细胞的研究

目的　体外诱导大鼠骨髓间质干细胞 (rMSC)分化为神经细胞。方法　用SD大鼠股骨骨髓细胞体外培养。用绞股蓝总甙加入无血清L DMEM诱导MSC分化为神经细胞。免疫细胞化学鉴定有神经元烯醇化酶 (NSE)、神经干细胞标志物巢蛋白 (nestin)和胶质纤维酸性蛋白 (GFAP)的表达。结果　大鼠骨髓间质干细胞在体外扩增 5～ 2 2代 ,对照组不加任何诱导剂 ,MSC可分化为神经样细胞 (5 3 1%± 4 3% )。加入绞股蓝诱导剂诱导 1～ 5h ,MSC形态转变为典型的神经样细胞(90 0 %± 4 6 % )。免疫细胞化学染色显示诱导出的神经样细胞 ,NSE、nestin、GFAP表达阳性。继续培养 12～ 19d ,5d后对照组所有细胞逐渐死亡。绞股蓝组持续诱导 12～ 19d后神经样细胞形态完好 ,大部分细胞变为圆形并聚集成团 ,NSE、nestin、GFAP表达阳性。如果换回正常培养液 ,神经样细胞可逆转回MSC并传代。结论　骨髓本身可能存在神经干细胞。大鼠骨髓间质干细胞用中成药绞股蓝诱导可分化为多种形态的神经样细胞。     

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。     

人脐带间充质干细胞体外扩增和向神经元样细胞定向诱导分化的研究

目的探讨人脐带间充质干细胞(MSCs)的体外分离、纯化、扩增和向神经元样细胞的定向诱导分化,以期为脐带MSCs的神经移植提供理论依据。方法无菌条件下收集剖宫产新生儿脐带,酶消化法获取MSCs,进行培养。用流式细胞仪检测MSCs的表面标志。取扩增3,5,10代的MSCs分别向神经元样细胞诱导,用免疫组化和RT-PCR法检测神经元样细胞特异性标志。结果脐带富含MSCs,且脐带MSCs(UCMSCs)强表达CD13、29、CD44、CD105,弱表达CD106,不表达CD34、CD11a、CD14、CD33、CD45。神经条件培养基诱导后的细胞平均有70%左右呈现典型的神经元样表型。免疫组化法检测发现不同代数的MSCs经诱导后均表达nestin,NSE,NeuN,NF-M,弱表达GFAP。RT-PCR显示诱导后NSEmRNA表达增加。结论MSCs存在于人脐带中,并且在体外有较强的增殖能力,特定条件下能够分化为神经元样细胞。     

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。     

bFGF和N2体外联合定向诱导骨髓间质干细胞向神经元样细胞分化

目的:将成年大鼠骨髓间质干细胞(mesenchymal stem cells，MSCs)体外定向诱导分化为神经元样细胞。方法:成年大鼠骨髓间质干细胞，进行体外扩增、纯化培养，对纯化后的MSCs，使用碱性成纤维生长因子(basic fibroblast growth factor，bFGF)和神经培养添加剂N2进行诱导，使MSCs分化为神经元样细胞，并进行免疫细胞化学方法鉴定。结果：95．6％的MSCs出现形态改变，呈神经元样。免疫细胞化学法鉴定，显示神经元特异性烯醇化酶(NSE)、神经丝蛋白(NF)和神经干细胞标志物巢蛋白(nestin)阳性表达。结论体外MSCs可以分化为神经元样细胞。     

骨髓间充质干细胞体外诱导分化为神经元样细胞的实验研究

目的　探索骨髓间充质干细胞 (MSCs)能否在体外诱导分化成神经样细胞 ,并初步探讨其分化机制。方法　培养大鼠MSCs,用二甲亚砜 (DMSO)和丁羟茴醚 (BHA)诱导分化 ,鉴定诱导分化前后的细胞是否表达神经细胞及神经干细胞的特异性标记蛋白 ,并研究其超微结构的变化。结果　诱导分化后 ,大部分MSCs变成双极、多极和锥形 ,并相互交织成网络结构 ,出现神经元特异性核蛋白 (NeuN)和巢蛋白 (Nestin)表达 ,无胶质纤维酸性蛋白(GFAP)和 2 3 环核苷酸磷酸二脂酶 (CNP)表达。部分MSCs转变为典型的神经元超微结构。结论　MSCs可以在体外诱导分化为神经元样细胞。     

体外培养的嗅鞘细胞能够促进骨髓间充质干细胞分化为神经元样细胞

目的探讨体外培养的嗅鞘细胞(OECs)对骨髓间充质干细胞(MSCs)分化的影响。方法实验分为OECs MSCs共培养组和MSCs单独培养组,在7d和14d两时间点观察MSCs的分化情况。用p75抗体免疫细胞化学染色鉴定OECs细胞的纯度;用巢蛋白(nestin)、神经丝蛋白(NF)、微管相关蛋白2(MAP2)、胶质原纤维酸性蛋白(GFAP)、突触后膜致密区蛋白(PSD)等抗体免疫细胞化学染色鉴定已分化的细胞表型。结果体外培养的MSCs经OECs诱导后分化为神经元样细胞,这些细胞能够表达NF、MAP2和PSD等神经元标记物,而不表达星形胶质细胞标记物GFAP。在培养7d,MSCs OECs7d组的MSCs分化为神经元样细胞的百分率与MSCs7d组比较有明显增高。在培养14d,MSCs OECs14d组的MSCs分化为神经元样细胞的百分率与MSCs14d组比较,也有明显增高。结论体外培养的嗅鞘细胞能够促进骨髓间充质干细胞分化为神经元样细胞。     

成年大鼠骨髓间充质干细胞体外分化为神经元样细胞

目的 探讨成年大鼠骨髓间充质干细胞(adult rat marrow mesenchymal stem cells,rMSCs)的体外增殖和特异性诱导分化为神经元样细胞的能力.方法 分别采用3种不同的诱导方法体外定向诱导第三至五代的rMSCs向神经元样细胞分化,并分别应用相差显微镜观察神经元样细胞和免疫细胞组化检测神经元样细胞所表达的神经元特异性标志[神经元特异性烯醇化酶(neuron specific enolase,NSE)和神经丝蛋白(neurofilament,NF)]及星形胶质细胞特异性标志[胶质纤维酸性蛋白(glia fiber acid protein,GFAP)],并进行神经元样细胞定量分析.结果 所采用的3种定向诱导方法都能使rMSCs特异性诱导分化为神经元样细胞,此神经元样细胞都能特异性地表达出NSE和NF,而不表达GFAP.经过定量计数分析发现用上述方法处理rMSCs 后出现NSE阳性的细胞约为75.5%±3.5%,出现NF阳性的细胞约为77.2%±2.8%.结论 rMSCs能在体外扩增、传代,并能被定向诱导分化为神经元样细胞.     

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。     

音速波状蛋白促进骨髓间充质干细胞向多巴胺能神经元分化

目的探讨音速波状蛋白（Shh）促进人骨髓间充质干细胞（MSCs）体外定向分化为多巴胺能神经元样细胞的作用。方法体外分离、扩增和鉴定人骨髓MSCs。采用不同诱导方案诱导MSCs向神经元和多巴胺能神经元样细胞定向转化后,进行抗神经巢蛋白（Nestin）、神经元特异烯醇化酶（NSE）、神经胶质纤维酸性蛋白（GFAP）、酪氨酸羟化酶（TH）和多巴胺转运体（DAT）等免疫细胞化学染色,并计算阳性细胞百分率。结果实验组诱导后MSCs能分化为具有典型神经元形态的细胞,可见NSE、Nestin、GFAP、TH和DAT等神经细胞标志表达;对照组MSCs细胞形态无明显变化,上述特异性标志物表达均为阴性。实验2组（诱导方案含Shh）与1组（诱导方案不含Shh）的NSE、Nestin、GFAP阳性细胞百分率的差异无统计学意义,但实验2组TH和DAT阳性细胞百分率明显高于实验1组,差异具有统计学意义（P〈0.05）。结论Shh可促进MSCs分化为多巴胺能神经元样细胞。     

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.     

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.