重症肌无力骨骼肌减少的25000蛋白分子鉴定

目的:解析重症肌无力(MG)骨骼肌特异减少的相对分子质量约25000的蛋白分子结构。方法:用双向电泳分离纯化骨骼肌25000蛋白,电喷射离子化质谱和Edman降解法分别测定其精确分子质量和N端部分氨基酸序列,基质辅助激光解吸电离飞行时间质谱测定其肽指纹图谱,在上述基础上,用ImmunoWesternblot分析骨骼肌蛋白与25000蛋白抗体及碳酸酐酶Ⅲ(CAⅢ)抗体的结合。结果:质谱和N端部分氨基酸序列的测定表明,电泳显示的表观相对分子质量为25000的蛋白其精确分子质量为29632.05,该蛋白的N端氨基酸可能是酰基化的;肽指纹图谱解析和蛋白资料库查询结果,结合对25000蛋白生化和生物学特征的了解,发现25000蛋白与CAⅢ的分子是非常相似的。结论:MG骨骼肌特异减少的相对分子质量约25000的蛋白分子很可能是已知的蛋白质CAⅢ,该活性物质与MG发病的关系值得进一步研究。     

重症肌无力患者抗骨骼肌抗心肌抗体与心脏损害

目的探讨重症肌无力（ＭＧ）合并心脏损害的发病机制。方法采用无创性心脏检查对５６例ＭＧ患者进行心电图、彩色多普勒二维超声心动图和心肌酶学检查;并应用免疫荧光技术,对其中４９例ＭＧ患者测定抗骨骼肌抗心肌抗体（ＳＨ－Ａｂ）。以正常人作对照检查。结果心电图异常率３０．３５％,超声心动图异常率１０．７１％,心肌酶学异常率４１．０７％。ＳＨ－Ａｂ阳性率４８．９％,对照组无１例有ＳＨ－Ａｂ。还发现伴心肌酶异常的ＭＧ患者ＳＨ－Ａｂ阳性率６９．６％（１６／２３）,心肌酶正常的患者ＳＨ－Ａｂ阳性率仅为３０．８％（８／３０）,伴胸腺瘤者（ＭＧＴ）ＳＨ－Ａｂ阳性率为４１．６％（５／１２）,不伴胸腺瘤者（ＭＧＮＴ）ＳＨ－Ａｂ阳性率仅为２４．３２％（９／３７）。另外,ＭＧＴ心电图、心肌酶学异常率均为５０％,均明显高于ＭＧＮＴ。结论ＭＧ的心脏损害可能与ＳＨ－Ａｂ滴度增高抗原抗体结合等自身免疫机制有关。     

抗骨骼肌抗体与重症肌无力

重症肌无力（M G ）是一种累及神经‐肌肉接头处乙酰胆碱受体（AchR）的自身免疫性疾病。其主要临床表现为骨骼肌的易疲劳性,经休息和服用抗胆碱酯酶药物可部分缓解,80％～90％的全身型MG患者血清中可检测到AchR‐Ab［1］。AchR‐Ab可用于MG的诊断,但其与病情严重程度、是否合并胸腺瘤和发病年龄无相关性,近来研究发现,T itin抗体、RyR抗体、MusK抗体等抗骨骼肌抗体在MG的发病机制中起重要作用,并与病情严重程度、发病年龄、性别、预后具有相关性。     

重症肌无力患者骨骼肌中碳酸酐酶Ⅲ蛋白减少的原因

目的 分析重症肌无力患者(MG)骨骼肌中碳酸酐酶Ⅲ(CAⅢ)蛋白和CAⅢ mRNA的表达,并与健康对照组进行比较,探讨MG骨骼肌CAⅢ蛋白缺乏的原因.方法 用Western blot分析17例MG患者与19名健康人骨骼肌CAⅢ蛋白的水平,逆转录-聚合酶链反应(RT-PCR)技术分析CAⅢ mRNA的表达.结果 Western blot显示,MG患者骨骼肌CAⅢ蛋白谱带密度低于健康人骨骼肌;经半定量分析,健康人骨骼肌CAⅢ蛋白水平的相对值为1.70±0.29,MG骨骼肌为0.76±0.08,两者差异有统计学意义(P=0.006).RT-PCR半定量结果为:健康人骨骼肌CAⅢ mRNA表达的相对值为0.29±0.04,MG骨骼肌为0.15±0.02,两组间差异亦有统计学意义(P=0.005).分析同一标本CAⅢ蛋白与CAⅢ mRNA表达,约77%的MG患者骨骼肌中两者呈一致性减少.结论 MG骨骼肌CAⅢ蛋白降低的主要原因是其本身CAⅢ mRNA的表达降低所致,骨骼肌CAⅢ mRNA的表达降低与MG发病的关系还需进一步阐明.     

重症肌无力患者骨骼肌中减少的25000蛋白即为碳酸酐酶Ⅲ的论证

目的论证重症肌无力(MG)患者骨骼肌中特异性减少的25000蛋白为碳酸酐酶Ⅲ(CAⅢ)分子。方法用双向电泳结合免疫Western blot分析25000蛋白抗体和CAⅢ抗体有免疫反应的蛋白质分子的物化特征,分别用免疫Dot blot与免疫Western blot观察两种抗体对纯化的25000蛋白及骨骼肌蛋白匀浆的竞争结合,用免疫Western blot分析健康人与MG患者骨骼肌CAⅢ的蛋白表达。结果双向电泳结合免疫Western blot显示,25000蛋白抗体和CAⅢ抗体识别的蛋白质具有相同的相对分子质量和等电点;免疫Dot blot与免疫Western blot的竞争结合证实25000蛋白与CAⅢ为同一物质;免疫Western blot表明,用25000蛋白抗体与CAⅢ抗体检测健康人与MG患者骨骼肌25000蛋白表达的结果亦几乎是相同的。结论MG患者骨骼肌特异减少的25000蛋白分子就是CAⅢ,这为进一步深入研究CAⅢ与MG的发病奠定了基础。     

重症肌无力P9-ZFD蛋白的骨骼肌亚细胞定位

目的：表达、纯化重症肌无力相关P9基因TRAF型锌指结构(P9 TRAF-type zinc finer domain，简称P9-ZFD)编码的蛋白质，制备P9-ZFD多克隆抗体，研究P9-ZFD蛋白的骨骼肌亚细胞定位。方法：应用逆转录-聚合酶链反应(RT-PCR)克隆编码P9-ZFD的cDNA序列，构建pET24a-P9-ZFD表达载体，在E．coli B121(DE3)中胞内诱导表达P9-ZFD蛋白，组氨酸亲和色谱法纯化P9-ZFD蛋白并免疫Balb／c小鼠制备其多克隆抗体。ELISA和Western blot鉴定抗体效价及其免疫特异性。免疫组织化学及免疫电镜观察P9-ZFD蛋白在骨骼肌中的表达部位及其亚细胞分布。结果：表达、纯化的P9-ZFD蛋白相对分子质量约30kD，纯度达95％以上。制备的P9-ZFD抗体具有特异的免疫反应性。免疫组织化学和免疫电镜结果显示，P9-ZFD蛋白的免疫染色部位集中沿MG骨骼肌细胞膜分布。结论：重症肌无力相关的P9-ZFD蛋白在MG骨骼肌细胞膜处表达，是一种骨骼肌细胞膜蛋白组分。     

25例重症肌无力的临床分析

对２５例重症肌无力进行回顾性分析。根据首发症状、病程，采用Ｏｓｅｒｍａｎ分型并结合影像学检查及手术胸腺的病理改变，将合并胸腺增生或胸腺瘤的重症肌无力病人的临床特点进行了比较。不论临床分型如何，都可能存在胸腺的异常（４７．６％）。伴胸腺瘤者发病年龄较大，男性居多，病程较短，危象发生率高。胸腺瘤术后仍发生危象有其免疫学基础。此时免疫抑制剂及抗胆碱酯酶的调整及合理应用仍然是重要的     

重症肌无力P9-ZFD蛋白的骨骼肌亚细胞定位

目的:表达、纯化重症肌无力相关P9基因TRAF型锌指结构(P9 TRAF-type zinc finger domain,简称P9-ZFD)编码的蛋白质,制备P9-ZFD多克隆抗体,研究P9-ZFD蛋白的骨骼肌亚细胞定位.方法:应用逆转录-聚合酶链反应(RT-PCR)克隆编码P9-ZFD的cDNA序列,构建pET24a-P9-ZFD表达载体,在E.coli BL21(DE3)中胞内诱导表达P9-ZFD蛋白,组氨酸亲和色谱法纯化P9-ZFD蛋白并免疫Balb/c小鼠制备其多克隆抗体.ELISA和Western blot鉴定抗体效价及其免疫特异性.免疫组织化学及免疫电镜观察P9-ZFD蛋白在骨骼肌中的表达部位及其亚细胞分布.结果:表达、纯化的P9-ZFD蛋白相对分子质量约30 kD,纯度达95%以上.制备的P9-ZFD抗体具有特异的免疫反应性.免疫组织化学和免疫电镜结果显示,P9-ZFD蛋白的免疫染色部位集中沿MG骨骼肌细胞膜分布.结论:重症肌无力相关的P9-ZFD蛋白在MG骨骼肌细胞膜处表达,是一种骨骼肌细胞膜蛋白组分.     

重症肌无力患者糖皮质激素受体含量与疗效的关系

目的探讨重症肌无力患者外周血白细胞糖皮质激素受体含量与应用糖皮质激素治疗效果的关系。方法用放射免疫法测定４１例患者和２５名健康对照者血糖皮质激素水平,采用放射性配体结合法测定患者经糖皮质激素治疗前后外周血白细胞糖皮质激素受体含量。结果（１）患者白细胞糖皮质激素受体平均值为（６７６５±９７４）位点／细胞,明显高于正常对照组［（２７４０±７２５）位点／细胞］（Ｐ＜０．００１）。（２）患者血浆皮质醇浓度（４５８±１７０）ｎｍｏｌ／Ｌ,对照组为（４１３±１５６）ｎｍｏｌ／Ｌ,二者差异无显著意义。（３）治疗前糖皮质激素受体位点数高者［（７３３４±５９９）位点／细胞,２５例］治疗效果好,而治疗前位点数低者［（５７７９±６５４）位点／细胞,１６例］治疗效果差（Ｐ＜０．０５）。（４）重症肌无力患者经糖皮质激素治疗后,糖皮质激素受体位点数较治疗前下降。结论重症肌无力患者外周血白细胞糖皮质激素受体含量增多,增多的程度与近期疗效有关,受体含量高者治疗效果好。     

重症肌无力患者骨骼肌肌肉蛋白成分分析

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Immunosuppressive treatment of rippling muscles in patients with myasthenia gravis

Rippling muscle disease is a rare autosomal dominant disorder that may occur sporadically. In this report two patients presenting with rippling muscles followed by myasthenia gravis are described. Our first patient developed rippling muscles about 1 month after infection with Yersinia enterocolitica. Two years later myasthenia gravis appeared. Our second patient had a 2-year history of asthma prior to the onset of rippling muscles which preceded the myasthenic symptoms by 4–8 weeks. Acetylcholine receptor and anti-skeletal muscle antibody titers were positive in both patients. In both patients the rippling phenomena worsened with pyridostigmine treatment but markedly improved after immunosuppression with azathioprine.     

重症肌无力患者肺功能改变及其与临床肌无力严重度的相关分析

目的 检测重症肌无力(MG)患者的肺功能改变,探讨其呼吸肌力变化与临床肌无力严重度、肺功能改变的关系. 方法 选取解放军第309医院MG治疗中心自2008年8月至2009年5月收治的Ⅰ型MG患者16例,Ⅱ型50例,选取同期健康体检者30例做为对照,检测并比较呼吸肌力[最大吸气压(PIM)、最大呼气压(PEM)、0.1s口腔闭合压(P0.1)]、和肺功能[肺活量(VC)、最大自主通气量(MVV)、峰流速(PF)、总气道阻力(R5)、中心气道阻力(R20]改变,并对Ⅱ型MG患者的呼吸肌力变化与临床肌无力严重度、MG患者呼吸肌力与肺功能的改变行相关性分析. 结果 与对照组比较,Ⅰ型MG患者MVV、PM降低,R20、R5增高,Ⅱ型MG患者VC、MVV、PF、PIM、PEM降低,R5增高,差异有统计学意义(P<0.05).与Ⅰ型MG患者比较,Ⅱ型MG患者PIM、PEM蹦减少,R5、R20增高,差异有统计学意义(P<0.05);Ⅱ型MG患者的PIM、PEM、MVV、VC与肌无力严重度绝对分数均呈正相关关系(r=0.550,P=0.002;r=0.653,P=0.000;r=0.511,P=0.000;r=0.353,P=0.010);MG患者的PIM、PEM分别与VC、MVV、PF均呈正相关关系(P<0.05),且PEM与PIM之间也呈正相关关系(r=0.650,P=0.000). 结论 Ⅰ型MG患者在疾病早期无明显呼吸肌无力表现时可有呼吸肌力减退和呼吸肌耐受力降低,故MVV、PIM、R20、R5可作为早期诊断MG的敏感指标;Ⅱ型MG患者呼吸阻力的增高和呼吸肌力的受损比Ⅰ型MG更严重.且这种损害伴有肌无力严重度绝对分数的增高;呼吸肌力的减退与肺功能的减退呈一致性.     

Acetylcholine-receptor-like protein from human thymoma associated with myasthenia gravis

Summary Cobrotoxin-binding protein was isolated by affinity chromatography from human thymoma which had been surgically removed from patients with myasthenia gravis. The protein was composed of polypeptides with a molecular mass of 40, 51, 65, and 74 kilodaltons as determined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl-sulphate. Isoelectric focusing of the protein gave pI values of 5.2–5.6 and 11. This is the first report of the isolation of the protein from human thymoma. These findings suggest that the cobrotoxin-binding protein from human thymoma patients with myasthenia gravis has subunits similar to those of fish electric organs or mammalian muscles.     

伴胸腺瘤重症肌无力的临床特点(附96例分析)

目的　研究伴胸腺瘤重症肌无力的临床特点。方法　对经手术病检证实的 96例MG伴胸腺瘤患者的临床资料进行回顾性分析 ,并采用 χ2 检验及t检验与 114 9例经影像学检查无胸腺瘤表现的MG患者进行比较。结果　胸腺瘤组男性发病者多 (男∶女 =1 82∶1) ,且多于 30岁后发病 (71 9% ) ,以肢体无力和延髓症状首发者多见 (4 3 8% ) ,按改良Os serman分型 ,以Ⅲ型和Ⅳ型为主 (4 5 8% ) ,危象发生率高 (38 5 % ) ,病死率高 (8 3 % )。结论　伴胸腺瘤的重症肌无力有其独特临床特点 ,充分认识这些特点将有利于指导对这类患者的临床诊断和治疗     

218例重症肌无力危象的临床分析

目的总结重症肌无力危象的临床特点及急救和预防经验.方法回顾性分析1956～2004年诊治的218例患者369例次重症肌无力危象的病例资料.结果死亡51例,病死率23.39%;近十年(1994～2004年)死亡4人,病死率4.2%.结论综合利用气管切开正压辅助呼吸、激素冲击治疗、丙种球蛋白静滴及血浆交换可改善重症肌无力危象的预后,且明显降低病死率.     

Giant cell polymyositis associated with myasthenia gravis and thymoma

We report a case of a 40-year-old woman who developed generalized muscle weakness over a period of 2 months. Physical examination revealed palpable masses in her arms and hands. Serum creatine kinase levels were elevated. Electromyography showed myopathic changes and 3 Hz repetitive nerve stimulation revealed a decremental pattern on repetitive nerve stimulation. Muscle MRI demonstrated increased signal intensity in the biceps brachii on T1-weighted images. Chest CT scan showed a mediastinal mass suggestive of thymoma. Muscle biopsy revealed giant cell polymyositis. The patient was treated with cholinesterase inhibitors and corticosteroids with improvement of strength, and subsequently underwent thymectomy followed by radiotherapy.     

Late onset myasthenia gravis

Late onset myasthenia gravis (MG) is defined as the onset of the disease after the age of 50 in a patient with no clinical or paraclinical evidence of a thymoma. Myasthenia gravis has a bimodal appearance for both sexes with a peak age of onset located in the early onset group and another peak for late onset of MG. Early onset of MG in men is approximately 10 years later than in females. In late onset MG, the thymus is smaller than in early onset and much of the lymphoid tissue has been substituted with fat. There is no morphological evidence that the thymus atrophy seen in late onset MG is any different from the thymus involution which is age-related. The AChR antibody concentration is lower in cases with late onset MG than it is in early onset and in thymoma-associated MG. Sera from late onset MG patients can be divided in 2 groups; those with and those without striated muscle (MGT 30) antibodies. Their presence is not an effect of age since they are not detected among old healthy individuals. Nor is it an effect of long MG duration, since there is no relation between titre and duration. Non-thymoma MG patients who demonstrate an immune response to titin identical to that observed in thymoma, have a worse prognosis and seem to do less well after thymectomy than late onset MG patients without muscle antiboides.     

伴其他自身免疫性疾病的重症肌无力临床特点分析

目的分析伴其他自身免疫性疾病的重症肌无力患者之临床特点、药物疗效、预后和转归。方法共83例重症肌无力患者,分为伴其他自身免疫性疾病重症肌无力(AIDMG)组(24例)和不伴其他自身免疫性疾病重症肌无力(NAIDMG)组(59例),比较两组患者性别、发病年龄、首发症状、胸腺异常等临床特点、不同治疗措施之疗效和预后。结果两组患者性别(χ2=8.467,P=0.004)、眼睑下垂侧别(χ2=9.830,P=0.007)、发病2年内病程情况(χ2=15.255,P=0.001)差异具有统计学意义,而发病年龄(χ2=1.728,P=0.228)、首发症状(χ2=0.252,P=0.791)、胸腺异常(χ2=3.200,P=0.202)组间差异无统计学意义。两组患者溴吡斯的明(χ2=0.411,P=0.395)、糖皮质激素(χ2=0.156,P=0.513)、静脉注射免疫球蛋白(χ2=0.359,P=0.462)、免疫抑制剂(χ2=0.081,P=0.526)、胸腺切除术(χ2=0.337,P=0.391)等治疗措施之疗效,以及眼肌型重症肌无力进展为全身型重症肌无力比例(χ2=1.826,P=0.148)、进展时间(Fisher确切概率法:P=0.639)、首发症状(Fisher确切概率法:P=0.196)和复发时间(Fisher确切概率法:P=1.000)差异均无统计学意义。结论 AIDMG患者多见于女性,首发症状为眼睑下垂,以双侧同时受累为主;发病2年内较NAIDMG患者更易复发。     

Electrophysiological profile of the patients with MuSK positive myasthenia gravis

Abstract

Objectives:

To determine the electrophysiological profile of our cohort of patients with muscle-specific tyrosine kinase (MuSK) positive myasthenia gravis (MG).

Methods:

Repetitive nerve stimulation test (RNS) and jitter analysis using concentric needle electrode were performed in 31 MuSK and in 28 acetylcholine receptor (AChR) positive MG patients.

Results:

Pathological RNS was verified in 16 (51·6%) MuSK and 26 (92·9%) AChR MG patients (P < 0·01). Pathological jitter analysis was registered in 28 (90·3%) MuSK and 26 (92·9%) AChR MG patients (P > 0·05). Increased jitter was present in extensor digitorum communis (EDC) in 23 (74·2%) MuSK and in 25 (89·3%) AChR MG patients (P > 0·05) as well as in orbicularis oculi (OO) muscle in 24 (85·7%) MuSK and 22 (81·5%) AChR MG patients (P > 0·05). Lower mean value of mean consecutive difference (MCD) and fewer potential pairs with increased jitter were registered in MuSK MG compared to AChR MG patients only in EDC muscle (P < 0·05). In MuSK MG patients, increased jitter was observed to be more frequent in patients with longer disease duration (P < 0·05) and also in those patients exhibiting more severe disease forms (P < 0·01) only in EDC muscle.

Discussion:

Repetitive nerve stimulation test has low sensitivity in MuSK MG patients, while jitter analysis shows high sensitivity, especially in facial muscles. The EDC muscle in MuSK MG patients usually shows increased jitter in more severe disease forms and later in the course of the disease.