自身免疫性重症肌无力的分型、治疗现状及特异性靶向治疗的展望

正重症肌无力(myasthenia gravis,MG)是最常见的神经肌肉接头疾病,以随意肌波动性肌无力和易疲劳为特点。病变主要累及神经肌肉接头(NMJ)突触后膜的乙酰胆碱受体(AChR),是乙酰胆碱受体抗体(AChR-Ab)介导的、细胞免疫依赖性及补体参与的NMJ传递障碍的自身免疫性疾病[1]。MG的治疗主要采用抗胆碱酯酶药、免疫治疗、降低血AchR-Ab水平的血浆交换及大剂量免疫球蛋白冲击疗     

肯尼迪病合并重症肌无力1例报道

肯尼迪病(Kennedy disease, KD)又称脊髓延髓肌萎缩症(SBMA), 是一种罕见的X染色体连锁隐性遗传的下运动神经元变性疾病, 发病机制为雄激素受体(AR)基因1号外显子编码多聚谷氨酰胺的CAG异常扩增[1]。重症肌无力(myasthenia gravis, MG)是由自身抗体介导的获得性神经肌肉接头传递障碍的自身免疫性疾病, 乙酰胆碱受体(AChR)抗体(AChR-Ab)为最常见的致病性抗体, 可干扰AChR聚集、影响AChR功能及神经肌肉接头信号的传递[2]。KD与MG都属于神经肌肉罕见病, 均可出现四肢无力和延髓麻痹等症状。笔者现报道河北以岭医院重症肌无力科收治的1例KD合并AChR-Ab阳性型MG的老年男性患者, 总结其治疗经验, 以期为临床作者提供参考。     

重症肌无力的治疗进展

重症肌无力(MG)是一种累及神经肌肉接头(NMJ)的获得性自身免疫性疾病。大部分MG患者由抗乙酰胆碱受体抗体(AChR-Ab)介导,该抗体可以与NMJ突触后膜上的烟碱型乙酰胆碱受体结合,通过减少突触后膜乙酰胆碱受体数量引     

重症肌无力相关抗体研究进展

重症肌无力(myasthenia gravis,MG)主要是以乙酰胆碱受体抗体介导的、细胞免疫依赖的、补体参与的神经-肌肉接头处的自身免疫反应性疾病.乙酰胆碱受体抗体(AChR-Ab)是最早发现的导致MG的自身抗体,然而随着研究的深入,在MG患者体内发现了越来越多的自身抗体,它们所导致的临床表型可能各有不同,现就与MG密切相关的自身抗体方面的研究进展综述如下.     

MG患者外周血Th17细胞与AChR抗体产生的关系研究

目的探讨重症肌无力(MG)患者外周血中Th17细胞及相关细胞因子白细胞介素17(IL-17)在MG发病中的作用。方法收集40例MG患者和10名健康人(对照组)外周血标本,采用流式细胞术检测外周血单个核细胞(PBMCs)中Th17细胞比例,反转录酶-聚合酶链锁反应(RT-PCR)检测PBMCs中维甲酸受体相关孤儿受体γt(RORγt)mRNA水平,ELISA检测血清中IL-17水平,放射免疫沉淀法检测血清中抗乙酰胆碱受体抗体(AChR-Ab)滴度;分离PBMCs中CD4~+T细胞和CD19~+B细胞与金黄色葡萄球菌肠毒素B(SEB)进行共培养,培养系统中加入人IL-17和(或)IL-21中和抗体,放射免疫测定法检测培养液中AChR-Ab滴度。采用MG评分(quantitative MG scoring system,QMGs)对MG的严重程度进行评估,并对MG患者的Th17细胞比例、RORγt mRNA和IL-17水平与病情QMGs的相关性,以及MG患者抗AChR-Ab滴度与PBMCs中Th17细胞比例的相关性进行分析。结果 MG患者PBMCs中Th17细胞比例[1.11%(0.90%,1.34%)]高于健康对照组Th17细胞比例[0.26%(0.08%,0.36%)](z=5.494,P0.001),且与疾病严重程度呈正相关(r=0.4394,P=0.0046);血清中IL-17水平和PBMCs中RORγt mRNA相对表达[分别71.46(53.91,104.76)pg/mL、2.63(1.94,3.12)]均较健康对照组[分别18.82(12.73,29.80)pg/mL、1.13(0.98,1.28)]显著增高(均P0.001);MG患者血清中抗AChR-Ab滴度[2.34(1.19,3.60)nmol/L]较健康对照组[-0.08(-0.24,-0.03)nmol/L]显著增高(z=4.662,P0.001),且与Th17细胞比例呈正相关(r=0.7066,P=0.0001)。MG患者外周血T、B细胞与SEB共培养后抗AChR-Ab水平高于未加入SEB时及健康对照(均P0.01);加入抗人IL-21或IL-17中和抗体后,两者AChR-Ab滴度与未加入抗体时AChR-Ab滴度比较均降低(均P0.05),且均仍高于MG患者未加入SEB时及健康对照(P0.01);在培养上清中同时加入抗人IL-21和IL-17中和抗体时AChR-Ab滴度明显低于加入单种抗体时,而与未加入SEB时及健康对照差异无统计学意义(均P0.05)。结论 MG患者外周血中Th17细胞可能通过IL-17促进AChR-Ab产生,参与疾病的病理过程。     

重症肌无力免疫治疗研究进展

重症肌无力(myasthenia gravis, MG)是乙酰胆碱受体抗体(acetylcholine receptor antibody, AChR-Ab)介导的、T细胞依赖和补体参与的神经-肌肉接头(neuromuscular junction, NMJ)处传递障碍的自身免疫性疾病[1],多是由于机体胸腺发育异常或其他原因产生抗乙酰胆碱受体抗体, 破坏突触后膜运动终板上的乙酰胆碱受体(AChR), 导致出现一系列肌无力的临床症状,如疲劳、虚弱、四肢无力等,呼吸肌受累常常是致命的死因.近年来,随着对MG发病机制及新疗法的深入研究和开展,该病的病死率明显下降、临床疗效也明显提高.现就其免疫治疗方面的现状和进展作一综述.     

放射免疫法定量检测乙酰胆碱受体抗体与重症肌无力患者临床特征的相关性

目的探讨乙酰胆碱受体抗体(AChR-Ab)与重症肌无力(MG)临床特征的相关性。方法采用放射免疫法检测115例MG患者及92例对照组(非MG神经系统疾病患者42例,健康体检者50名)血清AChRAb浓度,应用临床绝对评分记录MG患者病情严重程度。分析各组血清AChR-Ab浓度的差异,以及AChR-Ab浓度与MG患者临床特征的相关性。采用ROC工作特征曲线探讨AChR-Ab诊断MG的敏感度和特异度。结果MG患者血清AChR-Ab浓度中位数(四分位数间距,下同)为3.45(39.38)nmol/L,较非MG神经系统疾病患者[0(0)nmol/L]和健康体检者[0(0)nmol/L]增高(P0.01)。全身型MG(GMG)患者AChR-Ab浓度[25.45(46.14)nmol/L]较眼肌型MG(OMG)患者[0.58(3.56)nmol/L]增高(P0.01)。用ROC曲线法分析显示,以血清AChR-Ab浓度≥0.50nmol/L作为诊断MG界值时灵敏度为72.17%,特异度为100%,曲线下面积(AUC)=0.895(95%CI:0.849~0.941)。AChR-Ab浓度与发病年龄、病程及改良Osserman分型呈正相关(r=0.220,P0.05;r=0.184,P0.05;r=0.382,P0.01),但相关性较弱(均r0.5),与临床绝对记分无相关性(r=0.147,P0.05)。结论用放射免疫法检测血清AChR-Ab浓度诊断MG的灵敏度和特异度均高,有助于减少MG的漏诊率及误诊率,值得临床推广。     

血清乙酰胆碱受体抗体、肌肉特异性酪氨酸激酶抗体浓度与重症肌无力患者临床分型和疾病转归的关系

目的探索血清乙酰胆碱受体抗体(AchR-Ab)、肌肉特异性酪氨酸激酶抗体(MuSK-Ab)浓度与重症肌无力(MG)患者临床分型和疾病转归的关系。方法收集2014年5月-2015年5月在本院神经内科住院治疗的MG患者43例(MG组)和同期在本院健康体检的正常人43例(N组),采用酶联免疫吸附(ELISA)法检测血清AChR-Ab、MuSK-Ab浓度,并计算MG组患者治疗前后的肌无力绝对评分,分析不同临床分型的MG患者治疗前的血清AChR-Ab、MuSK-Ab浓度,并对治疗前后肌无力绝对评分和治疗前后血清AChR-Ab、MuSK-Ab浓度变化进行相关性分析。结果 (1)治疗前,MG组和N组的血清AChR-Ab浓度分别为0.786±0.237ng·mL~(-1)、0.298±0.113ng·mL~(-1),差异有统计学意义(均P0.05),血清Mu SK-Ab浓度分别为0.322±0.128ng·mL~(-1)、0.281±0.123ng·mL~(-1),差异无统计学意义(均P0.05);(2)血清AChR-Ab和MuSK-Ab在不同临床分型MG患者中的浓度均没有明显差异(均P0.05);(3)治疗后肌力绝对评分和血清AChR-Ab浓度均显著下降(均P0.05),而血清MuSK-Ab浓度在治疗前后没有显著变化(P0.05),并且治疗后的血清AChR-Ab浓度和治疗后的肌无力绝对评分呈正相关(r=0.797,P0.05)。结论血清AChR-Ab和MuSK-Ab的浓度与MG的临床分型无明显相关性,血清AChR-Ab对疾病的转归有一定的预示作用。     

伴肌萎缩重症肌无力4例分析并文献复习

目的探讨伴肌萎缩重症肌无力(myasthenia gravis,MG)患者的临床特征、抗体及电生理特点,提高对此少见疾病的认识。方法回顾性分析作者医院2003—2016年收治的伴肌萎缩MG患者4例的临床资料,分析其临床特征、抗体、神经电生理检查、治疗及预后特点。结果 4例患者病程中出现不同程度的肌肉萎缩,1例为手肌(左侧大鱼际肌、小鱼际肌及第一骨间肌)萎缩,3例为舌肌萎缩(其中1例同时伴面肌萎缩);抗体检查显示乙酰胆碱受体抗体(AChR-Ab)阳性3例,1例为抗骨骼肌特异性受体酪氨酸激酶抗体(MuSK-Ab)阳性。4例患者低频重复神经刺激波幅均可递减,高频刺激波幅未见明显递增。伴手肌萎缩MG患者针极肌电图检查结果提示神经源性损害。结论伴肌肉萎缩MG较罕见,MuSK-Ab、AChR-Ab阳性MG患者均可出现肌肉萎缩,其机制有待进一步明确;早期行神经电生理检查、AChR-Ab及MuSK-Ab测定有助于明确诊断。     

重症肌无力的治疗及其相关问题

重症肌无力(MG)是最常见的由乙酰胆碱受体抗体(acetylcholine receptor antibody,AChR-Ab)介导的神经-肌肉接头(NMJ)传递障碍的自身免疫性疾病。临床特征为部分或全身骨骼肌极易疲劳,常表现为上睑下垂、咀嚼吞咽困难、四肢乏力,严重者可发生MG危象而危及生命。MG治疗     

Denervation study of synapses of organ of corti of old world monkeys

Fine structural characteristics of synapses in the spiral organ of Corti were examined, with reference to differences between inner and outer haircell systems, and to location of neurons of origin of efferent axons. Surgical interruption of crossed olivocochlear bundle, of vestibular nerve, of facial nerve, and excision of superior cervical ganglia were used to determine the pathways of efferent axons. Interruption of the vestibular nerve near the brainstem results in degeneration of all efferent terminals on outer hair cells. Mid-line lesions at, and caudal to, the facial colliculus result in degeneration of about half of these efferent terminals. Efferent synaptic bulbs to the inner hair-cell system are small, of the order of one micron, and form type 2 junctions with afferent dendrites. They tend to have more large dense-core vesicles (about 80 nm) than the large efferent terminals of the outer hair-cell system, and appear to be the terminals of axons in the habenula perforata, which exhibit varicosities laden with large dense core vesicles. The varicosities are unaffected by excision of the superior cervical ganglia. So far as our material can reveal, it appears that the varicosities in the habenula perforata do not survive vestibular root interruption, nor do the efferent processes in the internal spiral bundle or at the base of inner hair cells. Most interestingly, the afferent processes of the inner hair-cell system, as identified for example by their relation to pre-synaptic bodies in the inner hair cells, are subject to a trans-synaptic reaction after severance of the vestibular root. They undergo a dramatic cytological transformation, characterized by increase of volume, engorgement with microtubules, microfilaments, microvesicles of various sizes, and clusters of lysosomes. Thus, both the efferent and afferent terminals of the inner hair-cell system show marked cytological differences from the corresponding terminals of the outer hair cell system.     

Mechanism of action of tubocurarine on nicotinic cholinoreceptors of neurons of the sympathetic ganglia of rats

Tubocurarine (Tc) effect on membrane currents elicited by acetylcholine (ACh) was studied in isolated superior cervical ganglion neurons of rat using patch-clamp method in the whole-cell recording mode. The "use-dependent" block of ACh current by Tc was revealed in the experiments with ACh applications, indicating that Tc blocked the channels opened by ACh. Mean lifetime of Tc-open channel complex, tau, was found to be 9.8 +/- 0.5 s (n = 7) at -50 mV and 20-24 degrees C. tau exponentially increased with membrane hyperpolarization (e-fold change in tau corresponded to the membrane potential shift by 61 mV). Inhibition of the ACh-induced current by Tc (3-30 microM/1) was completely abolished by membrane depolarization to the level of 80-100 mV. Inhibition of ACh-induced current was augmented at increased ACh doses. It is concluded that the open channel block produced by Tc is likely to be the only mechanism for Tc action on nicotinic acetylcholine receptors in superior cervical ganglion neurons of rat.     

The effect of age of onset of PD on risk of dementia

Background Dementia occurs in the majority of patients with Parkinson’s disease (PD). Late onset of PD has been reported to be associated with a higher risk for dementia. However, age at onset (AAO) and age at baseline assessment are often correlated. The aim of this study was to explore whether AAO of PD symptoms is a risk factor for dementia independent of the general effect of age. Methods Two community-based studies of PD in New York (n = 281) and Rogaland county, Norway (n = 227) and two population-based groups of healthy elderly from New York (n = 180) and Odense, Denmark (n = 2414) were followed prospectively for 3–4 years and assessed for dementia according to DSM-IIIR. All PD and control cases underwent neurological examination and were followed with neurological and neuropsychological assessments. We used Cox proportional hazards regression based on three different time scales to explore the effect of AAO of PD on risk of dementia, adjusting for age at baseline and other demographic and clinical variables. Findings In both PD groups and in the pooled analyses, there was a significant effect of age at baseline assessment on the time to develop dementia, but there was no effect of AAO independent of age itself. Consistent with these results, there was no increased relative effect of age on the time to develop dementia in PD cases compared with controls. Interpretation This study shows that it is the general effect of age, rather than AAO that is associated with incident dementia in subjects with PD. Received in revised form: 22 December 2005     

Limits of deinstitutionalization--perspectives of relatives of psychiatric patients

After a hopeful beginning, the social process of the reintegration of those with severe mental illness has come to a standstill. I am led to wonder whether "the community" really wants to live together with people suffering from severe mental illness, and if so, how closely? As long as the medical treatment of mental illness provided by the general practitioners is fundamentally deficient, as they are not able to prescribe the necessary interventions--such as out-patient psychiatric nursing, and service providers in the out-patient sector are content with offering increasingly intensive forms of care for the less seriously ill at the cost of the Social Welfare System--the reintegration of those with serious mental illness remains an illusion--which is mainly to the benefit of providers of residential care in homes and hostels.