常氧、低氧训练条件下肌肉蛋白表达及肌张力的变化**★

背景：环境因素以及运动水平均可显著引起肌纤维结构的变化。 目的：观察常氧、低氧训练条件下大鼠腓肠肌肌球蛋白、肌动蛋白的表达及肌张力的变化特征。 方法：将SD大鼠随机分为常氧对照组(氧体积分数20%，不进行任何处理)、常氧训练2，4，6周组、低氧训练2，4，6周组、低氧对照组(氧体积分数12.7%，不进行训练)。 结果与结论：无论在常氧还是低氧环境下，运动训练后大鼠腓肠肌质量、腓肠肌肌纤维截面积均明显增加(P < 0.05，P < 0.01)；运动训练6周后大鼠腓肠肌等长收缩最大张力显著增加(P < 0.01)；经运动训练后大鼠腓肠肌总MHC及α-actin随着训练时间的延长逐步升高，并且低氧训练组升高幅度高于常氧训练组。说明低氧训练可以更有效促进骨骼肌肌球蛋白、肌动蛋白的表达，增强肌张力，强化Ⅰ型肌纤维，并且训练时间越长，效果越显著，表明低氧训练是一种有效的运动训练途径。     

核因子κB在低氧诱导因子1α基因修饰神经干细胞上调血管内皮生长因子表达中的桥接作用**

背景：很多研究发现,在脑缺氧损伤区域核因子κB与血管内皮生长因子表达呈正相关。因此,作者大胆假设,核因子κB是否处于低氧诱导因子1α上调血管内皮生长因子作用通路上并起桥接作用。 目的：以低氧诱导因子1α修饰的神经干细胞为载体,观察核因子κB 在低氧诱导因子1α上调血管内皮生长因子表达通路中的作用。 设计、时间及地点：细胞学体外观察,于2008-03/12在佳木斯大学神经科学研究所完成。 材料：新生24 h内的Wistar大鼠,雌雄不拘。 方法：扩增腺病毒载体低氧诱导因子1α-绿色荧光蛋白后转染神经干细胞,荧光检测神经干细胞中低氧诱导因子1α-绿色荧光蛋白及空载体Ad-绿色荧光蛋白表达,分别提取基因转染后神经干细胞、空载体转染神经干细胞、正常神经干细胞蛋白。然后低氧诱导因子1α基因修饰的神经干细胞中按50,150,300 μmol/L浓度梯度加入核因子κB特异性抑制剂二硫氨基甲酸酞吡咯烷,Western Blot法检测其中血管内皮生长因子的表达变化。 主要观察指标：各组神经干细胞中低氧诱导因子1α、血管内皮生长因子和核因子κB 的表达;给予梯浓度核因子κB 特异性抑制剂后神经干细胞中血管内皮生长因子的表达。 结果：腺病毒低氧诱导因子1α-绿色荧光蛋白转染神经干细胞后基因表达强弱与MOI及转染时间有关;转染低氧诱导因子1α-绿色荧光蛋白后的神经干细胞中低氧诱导因子1α、血管内皮生长因子和核因子κB的表达呈正相关;给予梯浓度核因子κB 特异性抑制剂后腺病毒低氧诱导因子1α-绿色荧光蛋白修饰的神经干细胞中血管内皮生长因子的表达呈抑制剂浓度依赖性下调,各浓度组之间血管内皮生长因子表达差异有显著性意义(P < 0.05~0.01)。 结论：核因子κB位于低氧诱导因子1α上调血管内皮生长因子表达的信号通路上并起桥接作用。     

急性低氧条件下复氧后大鼠脑HIF—1α蛋白的表达与人参皂甙Rd干预研究

摘要：目的观察大鼠脑缺氧状态下缺氧诱导因子1α（HIF-1α）蛋白的表达及低氧状态下人参皂甙Rd干预对其影响。方法将成年Wistar大鼠90只随机分为急性低氧对照组、低氧预处理干预组、人参皂甙Rd预处理干预组,每组按缺氧后不同时间点（复氧后0h、4h、9h）再分为3亚组,每组10只大鼠。采用免疫组化法检测HIF-1α蛋白的表达。结果在缺氧后复氧即刻,HIF-1α蛋白少量表达,主要存在于海马细胞;随着时间的推移,在复氧后4h,HIF-1α表达逐渐达高峰,至9h时HIF-1α表达又明显减少。低氧预处理干预组及人参皂甙Rd干预组的实验结果发现HIF-1α表达较急性低氧对照组减少,与急性低氧对照组各时间点相比,差异均有显著性（P〈0．05）。两个干预组之间比较无统计学差异。结论急性低氧可以促使HIF-1α在大鼠海马神经细胞的表达,具有时间依赖性,低氧预处理干预及人参皂甙Rd干预均可促使大鼠脑组织HIF-1α表达减少。     

低氧复合运动通过NO-ATF1通路上调大鼠骨骼肌线粒体解偶联蛋白3表达**◆

背景：低氧复合运动可上调解偶联蛋白3的表达,提高骨骼肌线粒体对低氧的抵抗力,但其生物学效应及作用机制尚不清楚。 目的：观察单纯低氧及低氧复合运动对骨骼肌线粒体力能学及解偶联蛋白3表达的影响,并探讨NO-ATF1信号通路在其中的生物学效应。 方法：将60只SD大鼠随机分成常氧对照组、单纯低氧组、低氧复合运动训练组、低氧+ L-NAME组和低氧复合运动训 练+L-NAME组。低氧干预为常压低氧帐篷,模拟11.3%的氧体积分数;运动干预为低氧帐篷内跑台训练;L-NAME干预为饮用水中添加一氧化氮合酶抑制剂左旋硝基精氨酸甲酯。各种干预持续4周,硝酸还原酶法测定骨骼肌一氧化氮含量,荧光素酶发光法检测线粒体ATP合成活力,二氯荧光素法检测线粒体过氧化氢生成速率,实时荧光定量PCR法检测骨骼肌激活转录因子1和解偶联蛋白3 mRNA的表达,Western blot法检测骨骼肌磷酸化激活转录因子1和线粒体解偶联蛋白3蛋白的表达。 结果与结论：低氧复合运动显著上调骨骼肌解偶联蛋白3的表达及线粒体ATP的合成活力,抑制线粒体过氧化氢的产生,同时增加骨骼肌一氧化氮含量及激活转录因子1磷酸化水平,左旋硝基精氨酸甲酯抑制了低氧复合运动对线粒体的保护效应。说明低氧复合运动可通过NO-ATF1途径上调解偶联蛋白3的表达提高骨骼肌线粒体对低氧的抵抗力。 关键词：低氧复合运动;线粒体;一氧化氮;激活转录因子1;解偶联蛋白3;骨骼肌     

高压氧对递增负荷训练大鼠腓肠肌P53、Bcl-2蛋白表达的影响

背景：研究显示高压氧疗法在运动损伤与疲劳恢复方面具有较好的应用效果,但其机制尚不清楚。 目的：观察高压氧对递增负荷跑台运动后大鼠腓肠肌P53、Bcl-2蛋白表达及细胞凋亡的影响。 设计、时间及地点：随机对照动物实验,于2008-03/05在苏州大学运动人体科学实验室完成。 材料：2个月龄雄性SD大鼠24只,随机分为3组,安静对照组、递增负荷训练组、高压氧恢复组,每组8只。 方法：递增负荷训练组：坡度10%,递增负荷训练,第1~4周,每天20 m/min运动10 min,25 m/min运动10 min,30 m/min运动10 min,35 m/min运动10 min。第5~8周,每天20 m/min运动10 min,25 m/min运动10 min,30 m/min运动20 min,35 m/min运动20 min。高压氧恢复组：运动方案相同,运动后即刻用0.2 MPa压力的高压氧恢复60 min。安静对照组自由喂养,不进行训练。递增负荷训练组末次运动后1 h、高压氧舱恢复组恢复1 h及相应安静对照组分批麻醉处死,快速取腓肠肌立即用体积分数为0.1甲醛固定,制作切片。 主要观察指标：①苏木精-伊红染色观察各组大鼠骨骼肌细胞凋亡情况。②免疫组织化学检测各组大鼠骨骼肌细胞P53与Bcl-2蛋白表达情况。 结果：24只大鼠进入结果分析。①递增负荷训练组大鼠骨骼肌细胞凋亡数量增多,经高压氧恢复后细胞凋亡数量减少。②递增负荷训练组大鼠骨骼肌细胞P53蛋白表达增多,经高压氧恢复后表达显著减少。③递增负荷训练组大鼠骨骼肌细胞Bcl-2蛋白表达增多,高压氧恢复后未见减少。 结论：高压氧能够抑制递增负荷训练大鼠骨骼肌P53蛋白的表达,减少运动导致的大鼠骨骼肌细胞凋亡的发生。     

骨骼肌细胞αB-晶状体蛋白基因在大强度离心运动后的表达

背景：骨骼肌含有被称为“分子伴侣”的小热休克蛋白αB-晶状体蛋白，有可能在肌肉运动中具有重要的生理功能。 目的：观察离心运动后骨骼肌细胞αB-晶状体蛋白基因表达。 方法：将成年雄性Wistar大鼠随机分为安静对照组和运动后即刻组，运动后24 h组。安静对照组正常喂养，两个运动组进行一次性大负荷离心运动，分别取对照组腓肠肌和运动组运动后0和24 h的腓肠肌，使用冰冻切片原位杂交法检测αB-晶状体蛋白基因表达情况。 结果与结论：骨骼肌细胞αB-晶状体蛋白基因在对照组呈低水平表达，在运动后即刻和运动后24 h组均呈较高表达 (P < 0.05)，αB-晶状体蛋白基因表达杂交信号主要位于肌细胞膜下。结果证实，大强度离心运动可诱导骨骼肌细胞αB-晶状体蛋白基因表达增高。     

不同吸氧浓度对新生鼠视网膜血管发育和血管内皮生长因子表达的影响

背景：吸氧在早产儿视网膜新生血管中起重要作用,但其具体吸氧范围以及作用机制仍不明确。 目的：观察不同氧环境在新生鼠视网膜病的作用。 方法：将新生鼠40只分为空气组、波动1,2,3组,各10只,分别以正常空气、浓度50%、20%变化氧气、40%、10%变化氧气、50%、10%变化氧气环境饲养。饲养14 d后,视网膜铺片经ADP酶染色和视网膜切片经常规苏木精-伊红染色观察视网膜血管的增生情况。Western blot检测视网膜血管内皮生长因子的表达。 结果与结论：视网膜铺片波动2,3组新生血管钟点数、突破视网膜内界膜的血管内皮细胞数和血管内皮生长因子表达水平明显高于空气组和波动1组,空气组和波动组1组未见明显的视网膜新生血管。证实了反复血氧浓度波动可导致新生鼠视网膜新生血管增生性病变,吸入氧浓度差的波动与病变程度有关;低氧比高氧对发生视网膜病变可能更重要,血管内皮生长因子在视网膜新生血管形成中起着重要作用,促进视网膜新生血管形成。     

大鼠骨骼肌雷帕霉素靶蛋白mRNA表达与4周耐力运动的影响

背景：已有研究提示，雷帕霉素靶蛋白信号调控骨骼肌蛋白翻译过程，在运动引起的蛋白质合成变化中起作用。 目的：观察耐力运动对骨骼肌雷帕霉素靶蛋白mRNA表达的影响，以及雷帕霉素靶蛋白在运动诱导骨骼肌生长中的作用途径。 设计、时间及地点：随机对照动物实验，于2006-10/12北京体育大学运动人体科学学院实验室完成。 材料：健康雄性、SPF级2月龄的SD大鼠12只，体质量180~200 g，随机为运动组和对照组，每组6只。 方法：运动组先进行适应性训练：上坡跑，坡度为5°，速度分别为10，15，20 m/min强度递增的跑台运动，30 min/次， 1次/d，共6 d；然后进行正式运动：上坡跑，跑台坡度5°，速度20 m/min，60 min/次，1次/d，6 d/周，共4周的跑台运动。②对照组均不运动，其他生活条件与运动组相同。 主要观察指标：采用反转录-聚合酶链反应方法测定腓肠肌雷帕霉素靶蛋白mRNA表达，采用BCA方法测定腓肠肌总蛋白含量。 结果：实验纳入的12只大鼠全部完成训练，均进入结果分析，中途无脱落。①运动组腓肠肌总蛋白含量显著高于对照组 (67.0±11.7, 46.8±7.9；P < 0.05)。②运动组雷帕霉素靶蛋白表达量显著高于对照组表达量（0.43±0.04, 0.25±0.03；P < 0.05）。 结论：耐力运动后大鼠腓肠肌总蛋白含量上升，骨骼肌雷帕霉素靶蛋白mRNA表达上升，提示雷帕霉素靶蛋白可能参与肌肉生长对运动适应的调控。     

低频电刺激对坐骨神经损伤大鼠不同类型骨骼肌萎缩及内源性胰岛素样生长因子1表达的影响

背景：低频电刺激可以缓解骨骼肌的萎缩,但对肌纤维类型的影响尚不清楚,同时内源性胰岛素样生长因子1在萎缩后的肌纤维中的表达与电刺激的关系尚无公识。 目的：观察低频电刺激对坐骨神经损伤大鼠不同类型骨骼肌纤维萎缩情况及内源性胰岛素样生长因子1表达的影响。 方法：将健康雄性SD大鼠随机分为3组,切断模型组和电刺激组大鼠左侧坐骨神经制备失神经支配模型,适应5 d后,对电刺激组大鼠损伤侧腓肠肌施以2 Hz的电刺激,2次/d,每次持续20 min,正常组和模型组常规饲养。30 d后,取大鼠腓肠肌腹部,检测其肌纤维直径和数量;免疫组织化学法检测肌组织中胰岛素样生长因子1的水平。 结果与结论：失神经支配后,大鼠腓肠肌Ⅰ、Ⅱ型肌纤维直径减小,Ⅰ型肌纤维数比例增大。与模型组比较,电刺激组大鼠腓肠肌Ⅰ、Ⅱ型肌纤维直径有所增大,尤以Ⅰ型肌纤维直径增大更明显(P < 0.05)。同时,电刺激组大鼠腓肠肌中胰岛素样生长因子1的表达也明显高于模型组(P < 0.05)。提示,2 Hz的电刺激可促进胰岛素样生长因子1的表达,减轻Ⅰ型肌纤维的萎缩。     

脐血内皮祖细胞尾静脉与局部注射治疗糖尿病下肢缺血

背景：内皮祖细胞治疗糖尿病下肢缺血临床及动物实验多采用局部肌肉注射。 目的：比较脐血内皮祖细胞鼠尾静脉与局部注射治疗糖尿病下肢缺血效果的差异。 方法：取Wistar雄性大鼠分成5组：①糖尿病射线照射后结扎双后肢股动脉,尾静脉注射内皮祖细胞(DLV)。②糖尿病结扎双后肢股动脉左后肢局部肌肉注射PBS(DLC),右后肢局部肌肉注射内皮祖细胞(DLM)。③正常大鼠射线照射后结扎双后肢,尾静脉注射内皮祖细胞(NLV)。④糖尿病不结扎不注射内皮祖细胞(DC)。用绿色荧光示踪内皮祖细胞,苏木精-伊红染色检测肌纤维间毛细血管数,RT-PCR检测双后肢肌肉血管内皮生长因子mRNA水平。 结果与结论：DLV组与DLM组比较,右后肢腓肠肌溃疡及缺血好转明显,二者无明显区别;有明显荧光,差别不明显,Ⅷ因子免疫组织化学染色肌纤维间毛细血管数多,相互间无明显差别;腓肠肌血管内皮生长因子表达差异无显著性意义(P > 0.05)。提示脐血内皮祖细胞治疗糖尿病大鼠下肢缺血尾静脉注射与局部肌肉注射效果相当。     

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.     

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.     

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.     

Special Pharmacokinetic Considerations in Children

Summary: Pediatric patients have greater degrees of pharmacokinetic variability and unpredictability than adults. This variability results from the effects of pharmacogenetics, age and growth, prior and current comedication, and disease. Newborns with seizures have the least predictable dosage requirements, and their needs change as drug-eliminating mechanisms mature in the neonatal period. Infants have the highest relative capacities to eliminate antiepileptics of any age group and require the largest relative doses. In addition to age-related trends, children demonstrate the same drug-specific, pharmacokinetic phenomena that adults do, including nonlinear phenytoin elimination, nonlinear valproate binding, and autoinduction of carbamazepine. Intercurrent illness and drug interactions further modify the age-related pharmacokinetic patterns in children and make dosage requirements even more unpredictable. Recent studies have shown that febrile illness can affect drug elimination, sometimes decreasing drug levels by 50% or more. Intermittent treatment with benzodiazepines administered either orally or rectally can be an important adjunct and help minimize this type of problem for children with marginally controlled epilepsy. Intermittent benzodiazepines are also helpful for children who have febrile seizures and who need only occasional antiepileptic protection.