联合应用PCR-SSCP、PCR-限制性酶切和连锁分析法对脊髓性肌萎缩症进行产前基因诊断

目的：建立脊髓性肌萎缩症（SMA）的基因诊断方法。并且应用于SMA的产前基因诊断。方法：应用聚合酶链反应（PCR）－单链构像多态性（SSCP）分析和PCR－限制性酶切分析法对运动神经元存活基因（SMNT）的第7外显子进行缺失检测；应用紧靠SMN基因的微卫星标记进行单体型连锁分析。结果：家系1的患者为两个SMNT基因的同源缺失，胎儿虽然未发现SMNT基因的同源缺失，但是从母亲那儿遗传了一条与患者相同的异常5号染色体，是SMA携带者；家系2的胎儿亦未发现SMNT基因的同源缺失，两家系先证者的母亲各生下了一名正常儿。结论：PCR－SSCP分析，PCR－限制性酶切和单体型连锁分析法是诊断SMA的有效方法，三者联合使用可以相互验证，互为补充，提高产前基因诊断的准确率成功率。     

杆状体肌病12例患者临床与病理特点

目的 探讨杆状体肌病患者临床与病理特点.方法 采用肌肉酶组织化学染色方法和电镜技术观察12例杆状体肌病患者病理特点,收集临床资料进行归纳分析.结果 在本组12例杆状体肌病患者中,7例为先天轻症型,表现为下肢或四肢无力起病,病程进展缓慢,呈良性过程；3例为儿童起病型,均表现为下肢无力,病程持续加重,有肌萎缩现象；2例为成人起病型,双下肢无力起病,累及上肢肌和延髓部肌肉,进展较快,肌萎缩明显,1例出现呼吸困难.部分病例出现狭长面容、双侧弓形足等发育畸形,血清肌酸激酶值正常或稍高,肌电图提示为肌源性损害.在所有患者的肌肉病理切片中,有半数以上肌纤维均出现成堆的杆状体结构；Ⅰ型纤维占优势并呈萎缩现象,且杆状体均出现在Ⅰ型纤维中；改良Gomori染色时杆状体结构最清楚；电镜观察到部分肌原纤维发育不良,如肌丝断裂,排列不整和肌原纤维粗细不一,肌原纤维Z线细小、不规则或消肖失；大量电子密度高的杆状体结构主要出现在肌膜下的肌核周围,少数在肌纤维中央；高倍电镜观察到杆状体结构实际上是肌原纤维中的一段,只是密度很高,但也可是一块无结构的高电子密度体.结论 本组具有3个类型,成人型病情较重,半数以上肌纤维出现杆状体成堆是诊断的关键,电镜有助于确诊.     

平山病的神经电生理特点分析

目的 分析平山病的神经传导以及肌电图（EMG）特点,以提高对平山病的诊断认识.方法 对12例确诊平山病患者进行常规肌电图、感觉及运动神经传导速度检测.结果 患者患侧上肢及对侧上肢远端肌肌电图呈神经源性改变.上肢神经存在远端运动潜伏期（DML）延长及复合肌肉动作电位（CMAP）波幅下降的现象.结论 平山病主要发生在青春期,临床表现和肌电图检查提示局限于下位颈髓的前角病变.     

Estimating bone mineral content based on different types of muscle strength tests

The aims of this pilot study were to verify which muscle strength tests better explain bone mineral content (BMC) of the femoral neck and lumbar spine and to develop predictive equations to estimate femoral neck and lumbar spine BMC. Twenty-nine subjects aged 56–76 years old (12 women and 17 men) participated in the study. Femoral neck and lumbar spine BMC was evaluated by Dual X-ray absorptiometry (DXA). Muscle strength measurements included maximal isometric voluntary contractions of knee extensors and flexors, vertical jump, 5-repetition maximum of the leg press (5-RM_LP) and seated leg curl (5-RM_LC), and handgrip strength. Women presented a moderate to strong correlation between femoral neck BMC and 5-RM_LP (r = 0.819), 5-RM_LC (r = 0.879), knee extensors peak torque (r = 0.699), and handgrip strength (r = 0.663), as well as between lumbar spine BMC and the 5-RM_LP test (r = 0.845) and manual grip strength (r = 0.699). For females, the 5-RM_LP and 5-RM_LC tests most fully explained femoral neck BMC (R² = 0.859) and the 5-RM_LP test and body mass explained lumbar spine density (R² = 0.757) for females. Men did not present correlations between BMC and strength variables. For females, the 5-RM_LP and 5-RM_LC variables explained the variations of femoral neck BMC, while 5-RM_LP and body mass explained lumbar spine BMC. Future studies should evaluate a larger sample size and prioritize the strength tests with a greater predictive capacity.     

屈颈MRI对青年性上肢远端肌萎缩症的诊断价值

目的评价屈颈MRI对青年性上肢远端肌萎缩症的诊断价值。方法男性患者5例，平均年龄21岁，临床表现为一侧或两侧上肢远端肌萎缩。对照组为健康志愿者，21岁男性8例。2组均行常规及屈颈颈椎MR平扫，矢状、轴面SET1WI、T2WI、液体衰减反转恢复（FLAIR）序列扫描。结果常规颈椎扫描：5例患者下段颈髓变细；屈颈位MR扫描：下颈段颈6以下脊髓前屈、变扁平，矢状径4～6mm，硬膜囊后壁前移，硬膜后间隙明显增宽，可见多发条状、迂曲流空信号影及软组织信号。对照组：常规扫描，下颈段脊髓（颈6～胸2）可见颈膨大，屈颈位脊髓略变细（6～7mm），硬膜囊后壁无前移，硬膜后间隙未见扩张血管影。结论屈颈MRI有助于显示下颈段脊髓及硬膜囊改变，结合临床资料可准确诊断青年性上肢远端肌萎缩症。     

核因子κB p65在肌肉萎缩中的表达与被动运动对其影响

目的 研究核因子κB(nuclearfactor kappa B,NF-κB)p65在失神经骨骼肌中的表达及被动运动对其影响作用,探讨失神经骨骼肌萎缩的分子机制及防治方法.方法 选Wistar大鼠42只,随机分成健康对照组(6只)、失神经对照组(18只)和被动运动组(18只).失神经对照组和被动运动组建立右下肢失神经腓肠肌动物模型.被动运动组大鼠采用右下肢被动运动300次/d.分别在术后2 d、14 d及28d取其双侧腓肠肌称重,计算肌湿重比,采用RT-PCR和Western Blot检测大鼠右侧失神经腓肠肌NF-κB p65的mRNA和蛋白表达水平,根据实验结果做统计处理数据得出结论.结果 大鼠腓肠肌失神经支配后肌肉湿重比持续下降,NF-κB p65的mRNA和蛋白表达在2 d、14 d、28d持续增加(P＜0.05),术后14 d、28d被动运动组腓肠肌湿重比高于同期失神经对照组(P＜0.05),被动运动组mRNA和蛋白的表达在各个时间点低于失神经对照组(P＜0.05),差异有统计学意义.结论 在失神经骨骼肌萎缩中,NF-κB p65的表达持续增高.被动运动可以通过干扰NF-κB p65的mRNA和蛋白质的表达来延缓失神经骨骼肌萎缩.     

失神经骨骼肌NF-kappa B的表达变化与线粒体通透性转换孔开放及细胞凋亡的关系

目的 通过研究去神经骨骼肌细胞核转录因子kappa B(nuclear factor of kappa B,NF-kappa B)p65与线粒体通透性转换孔(mitochondrion permeability transition pore,MPTP)及细胞凋亡的关系,探讨失神经肌萎缩的相关机制.方法 Wistar大鼠30只,随机分为健康对照组、去神经2 d组、去神经7 d组、去神经14 d组、去神经28 d组.建立右下肢腓肠肌失神经支配模型,对照组仅做假手术.采用Western Bloting检测大鼠腓肠肌NF-kappa B p65蛋白表达水平,共聚焦荧光显微镜观察MPTP的开放情况,脱氧核糖核苷酸转移酶介导的缺口末端标记(Tunnel)技术检测细胞凋亡情况,并结合肌湿重进行相关性分析.结果 大鼠失神经支配后随着肌湿重比的下降,NF-kappa B p65蛋白、MPTP的开放以及骨骼肌细胞的凋亡率在各个时间点持续增加,且明显高于对照组,差异有统计学意义(P＜0.05),NF-kappa B与MPTP的开放(r=-0.896,P＜0.01)以及凋亡率(r=0.890,P＜0.01)密切相关,并且NF-kappa B和凋亡率的升高与肌湿重比呈负相关关系(r分别为-0.919、-0.924,P均＜0.01).结论 NF-kappa B在失神经肌萎缩中起重要作用,其作用机制与MPTP的开放及细胞凋亡有关.

Abstract：

Objective To analyze the relationship of nuclear factor of kappaB (NF-κB) p65 to mitochondrion permeability transition pore (MPTP) and apoptosis during denervation atrophy of the gastrocnemius muscle, and delineate their potential roles in skeletal muscle atrophy. Methods Thirty Wistar rats were randomly divided into 5 groups: control group, 2 day denervation group, 7 day denervation group, 14 day denervation group, and 28 day denervation group. The gastrocnemius muscle was denervated by transection of the sciatic nerve. Sham operation was done in the control group. Levels of NF-κB p65 protein and the opening of the mitochondrial permeability transition pore in the gastrocnemius muscle were detected respectively by Westem Bloting and confocal fluorescence microscopy. The apoptotic cells in atrophic muscles were quantitated with Tunel. Muscle wet weight was also measure for comparison. Results At different time points after denervation, the levels of NF-κB p65, the opening of MPTP and apoptosis of gastrocnemius were significantly higher than those in the normal group ( P ＜ 0.05). Furthermore NF-κB p65 had a positive correlation with the opening of MPTP (r= - 0.896, P ＜ 0.01) and with the ratio of apoptosis (r = 0.890,P ＜0.01 ), while the increase of NF-κB p65 and apoptosis was negatively correlated with the ratio of muscle wet weight ( r = - 0. 919,-0.924, P ＜ 0.01 ). Conclusion NF-κ3 plays an important role in denervation skeletal muscle atrophy.This effect is related to the opening of MPTP and apoptosis.     

A cervical myelopathy with a Hirayama disease-like phenotype

A 21-year-old man with a muscular atrophy of the left distal upper extremity is presented. The disorder had been progressive over a few years, showing an exacerbation of the hand’s weakness when the patient worked in a chilled environment (i.e., in a cold room). The patient’s diagnostic work-up was extensive and the MRI documented the presence of a cervical myelopathy, associated to an inversion of the physiological lordosis at the C5–C6 level, with a phenotype highly resembling Hirayama disease. This case indirectly supports the debated hypothesis that juvenile amyotrophy of the upper limb (Hirayama disease) is actually a type of cervical myelopathy, with a likely ischaemic pathogenesis of the ventral horns.     

神经干细胞移植防治骨骼肌失神经肌萎缩的电生理研究

目的探讨采用神经干细胞移植的方法防治骨骼肌失神经萎缩的可行性。方法采用机械分离的方法从孕14～16 d的SD孕鼠中获取神经干细胞,并于神经元限定性培养基中进行传代培养,制备神经干细胞单细胞悬液。采用切断右侧胫神经的方法建立腓肠肌失神经支配的动物(SD大鼠)模型。将108只SD大鼠按注射药物的不同随机分为3组,每组36只大鼠。实验组:将神经干细胞悬液注射到切断的胫神经远端。损伤组:注射等量的生理盐水。对照组:注射等量的细胞培养液。术后8、12周采用HRP逆行示踪技术检测失神经骨骼肌重获神经再支配的情况,并应用肌肉电生理方法对重获神经再支配的骨骼肌进行功能评价。结果术后8、12周实验组用电刺激细胞移植部位的腓肠肌,均可引出肌肉收缩活动;且随着时间的延长,单次收缩的波幅、速度,和强直收缩的时间和强直收缩波幅的恢复率均进一步得到改善。对照组和损伤组均未能引出肌肉活动。结论神经干细胞移植能够实现失神经骨骼肌的神经再支配,并且能够与骨骼肌建立起功能性突触连接,有效预防骨骼肌的萎缩。     

平山病患者的临床电生理及颈磁共振成像研究

目的 研究平山病(HD)患者的临床特征、肌电生理及颈磁共振成像(MRD特点.方法 观察15例HD患者的特殊临床表现.检测双侧上肢远端及下肢常规肌电图及周围神经传导速度.行颈部自然位、过屈位及过伸位MRI扫描,观察低位颈髓有无萎缩及颈椎曲线情况.结果 15例患者均为男性,青春期起病.病变均表现为上肢远端肌肉、骨间肌、鱼际肌萎缩和双手厥冷无力.肌电图检查示患者受累侧远端肌运动单位平均时限宽,多相波增多,波幅显著增高(巨大电位),主要位于C7、C8及T1节段.颈自然位MRI示9例患者低位颈髓萎缩,主要在C5、C6节段.所有患者过屈位时颈髓前移、变扁平,变扁节段以C6为主.结论 HD主要发生在青春期,以男性多见,临床表现和肌电图检查提示局限于下位颈髓的前角病变,颈部自然位和过屈位MRJ不同的特点可协助诊断.