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1.
A 25-year-old, emaciated man without medical treatment was found to have died suddenly at home by his mother. At autopsy, there were no injuries to his body, but significant circulatory insufficiency was observed. Electron microscopy revealed abnormal mitochondria in cells of the cardiac conduction system. The conduction system was filled with mitochondrial size abnormalities and mitochondrial cristae abnormalities. No notable abnormal findings were observed in other organs. Genetic examination of the blood revealed the mitochondrial pathogenetic variant m.3243A>G. Epileptic seizures, diabetic ketoacidosis, and hyperosmolar hyperglycemic state were unlikely to be the cause of sudden death. The cause of death was diagnosed as arrhythmia possibly induced by the failure of the cardiac conduction system due to mitochondrial disease. This is a rare case of sudden death caused by an accumulation of abnormal mitochondria in the cardiac conduction system. 相似文献
2.
背景:原发性线粒体病具有高度的临床和遗传异质性,其中周围神经是线粒体病的常见受累器官之一。
目的:总结COX20基因变异相关周围神经病的临床表型及遗传学特征。
设计:病例系列报告。
方法:回顾性收集2018年5月至2020年5月复旦大学附属儿科医院诊治的COX20基因变异相关周围神经病患儿的临床资料,总结其临床表现、基因检测结果及治疗效果,并以“COX20”、“线粒体复合物Ⅳ缺乏症(Complex Ⅳ deficiency)”为关键词检索中英文数据库。检索时间均为从建库至2021年12月。总结已报道COX20基因变异与临床表型的关系。
主要结局指标:临床表型和COX20基因变异位点。
结果:4例患儿纳入分析,男、女各2例,其中3例自幼运动发育落后。4例均在儿童期起病,均以行走不稳为首发症状。肌电图均提示多发性周围神经损害改变,感觉神经轴索受累为主。4例患儿均携带COX20基因复合杂合变异,包括错义变异2个,无义变异和移码变异各1个,其中移码变异c.262delG(p.E88Kfs*35)尚未见报道。文献复习目前共报道COX基因变异18个家系22例患儿(包括本文病例),起病中位年龄为5(1.0~17)岁,22例均以行走困难或步态不稳起病,11例(50.0%)有精神运动发育迟滞,病程中14例(63.6%)出现构音障碍,14例(63.6%)出现肌力下降和/或足部畸形,8例(36.4%)出现共济失调,6例(27.3%)出现肌张力障碍,5例(22.7%)存在认知倒退等。21例患儿行神经传导及肌电图检查,19例(90.5%)提示多发性周围神经病变。头颅(18例)及脊髓(10例)MR检查提示,脊髓萎缩4例(40%),小脑萎缩4例(22.2%)。9例患儿已无法独立行走,丧失独立行走能力中位年龄为10(7~21)岁。目前共报道9个变异位点,4种变异类型,其中错义变异5个,剪切变异2个,无义变异和移码变异各1个。
结论:COX20基因变异患者多早期起病,以周围神经系统病变为主要表现,可合并构音障碍、共济失调、肌张力障碍、认知倒退等,病情逐渐进展,致残率高。COX20基因变异类型以错义变异最常见。 相似文献
3.
线粒体脑肌病属于罕见性母系遗传病,本文回顾性分析了1家4例高乳酸血症-卒中样发作综合征(MELAS)型线粒体脑肌病患者,其主要表现为卒中样发作、头痛、癫痫、高乳酸血症、肌肉不耐受疲劳、高级智能下降、听力下降和身材矮小等,结合特征性影像学变化、基因检测及肌肉活检明确诊断,并结合文献对只有女儿能将其线粒体DNA(mt-DNA)传递给下一代的母系遗传MELAS型线粒体脑肌病临床特点进行了总结分析,旨在帮助临床认识此病,进一步提高MELAS型线粒体脑肌病的临床诊断率。 相似文献
4.
5.
褪黑素和6-羟褪黑素保护神经细胞抗缺血再灌注损伤比较研究 总被引:1,自引:0,他引:1
目的研究褪黑素(Mel)和6-羟褪黑素(6-OHMel)神经保护作用及作用机理。方法体外培养N2a细胞,模拟缺血再灌注(OGSD),加入Mel和6-OHMel,检测以下指标:①细胞生存能力:MTT法、乳酸脱氢酶释放;②细胞凋亡分析:DNA片断化,细胞色素C,Caspase3活性;③活性氧(ROS)和线粒体跨膜电位。结果①Mel和6-OHMel都能减轻OGSD诱导的N2a细胞损伤,Mel的作用强于6-OHMel。②Mel和6-OHMel均能抑制细胞色素C释放,但6-OHMel强于Mel。③Mel和6-OHMel都能稳定线粒体跨膜电位,但Mel作用时间比6-OHMel长。④Mel和6-OHMel能清除ROS,6-OHMel表现为直接作用,Mel表现为间接作用。⑤Mel和6-OHMel均能抑制caspase3的活性,但是作用时间不同。6-OHMel表现在OGSD后12h,Mel在OGSD后24h。结论Mel和6-OHMel的神经保护作用与其抗氧化、稳定线粒体功能相关,Mel的作用机制更复杂。 相似文献
6.
Hoon-Chul Kang Ji Won Kwon Young Mock Lee Heung Dong Kim Hong Jin Lee Si Houn Hahn 《Child's nervous system》2007,23(11):1301-1307
OBJECTIVES: This study sought to characterize epileptic phenotypes in children with nonspecific mitochondrial disease (MD) and to evaluate MD diagnostic approaches. METHODS: A retrospective analysis of the medical, electroencephalogram, and laboratory records of 142 patients with epilepsy was performed. The patients were evaluated for MD, and 124 patients were included in the final cohort. The MD criteria used included an oral glucose lactate stimulation test (OGLST) and urine organic acid/plasma amino acid (UOA/PAA) assays as metabolic indicators of modified Walker criteria, as suggested by Bernier et al. (Neurology 59:1406-1411, 2002). RESULTS: Twenty-two patients were classified as having definite MD (9), probable MD (5), possible MD (6), or pyruvate dehydrogenase (PDH) deficiency (3), including one patient which showed a respiratory chain (RC) defect and PDH deficiency. Seven out of eight patients in whom significant RC defects were observed showed complex I defects. In 14 patients, epileptic seizures start at infantile ages. Of 17 patients who substantially presented generalized seizures, 4 patients started with partial seizures. Five patients consistently presented only partial seizures. The OGLST and UOA/PAA assays were useful for a more precise diagnosis of MD, although low positive predictive value of the OGLST was regrettable. No patient was classified as definite MD by Walker's original criteria, but the use of our revised MD criteria resulted in the classification of nine additional patients as definite MD. CONCLUSIONS: MD manifested considerable diverse epileptic phenotypes and should be considered in the differential diagnosis of epilepsy in children with unexplained encephalomyopathy and progressive and fluctuating clinical courses. 相似文献
7.
Robert J. Hitzemann Jack Hirschowitz David L. Garver 《Journal of affective disorders》1986,10(3):227-232
Membrane order was measured in the erythrocyte ghost membranes of DSM-III schizophreniform disorder (SF), DSM-III schizophrenic (SCZ) and DSM-III manic (bipolar) (M) patients and a group of age- and sex-matched controls. Fluorescence polarization with the probe 1,6-diphenyl1-1,3,5-hexatriene was used to determine the steady-state fluorescence anisotropy (rs). The SF group showed a significant increase in rs (Δrs = 0.037) from the control group. Although the means were not significantly different, 3 of 8 Ms and 5 of 8 SCZs also had rs values > the highest control value. Thermotropic behavior of the membranes was evaluated over the range of 40 to 20°C. No difference among groups in membrane enthalpy was detected. Thus, the differences in rs appear to be associated with differences in entropy. Phosphatidylcholine (PC) levels, which were known to be abnormal in these patients, were compared with the rs values. A significant (P < 0.001, R= -0.63) linear correlation between rs and membrane PC levels was observed. Overall these data further support the view that unusual membrane biophysical factors may occur with high frequency in the psychoses and affective disorders. 相似文献
8.
F. Degoul M. Diry F. Viader E. Boitier C. Marsac B. Eymard N. Romero M. B. Delisle B. Lechevalier F. Chapon 《European journal of neurology》1995,2(6):573-579
We have identified the A3243G heteroplasmic point mutation in mitochondrial DNA from a female patient with headache as the main clinical feature. The mitochondrial origin of her disease was only suspected because of her brother with MELAS syndrome. Morphological and biochemical studies failed to reveal mitochondrial respiratory chain dysfunction in her muscle which contained 65% of mutated mitochondrial DNA molecules. Molecular studies performed among four generations (in the blood of seven subjects) showed the variable transmission of mutated molecules and pointed out the difficulty in giving genetic counsel. 相似文献
9.
Summary In a patient with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes [MELAS] who had normal mitochondrial enzyme activity, high doses of coenzyme Q10 (CoQ) were administered. Clinical improvement with decreased serum lactate and pyruvate levels was observed. Though the mechanism of action of CoQ is not known, a trial is worthwhile in patients with MELAS. 相似文献
10.
目的研究二氮嗪开放线粒体ATP敏感性钾通道对大鼠脑缺血再灌注细胞凋亡的影响。方法采用线栓法建立大鼠局灶性脑缺血再灌注损伤模型,将20只大鼠随机分成4组,假手术组、缺血组、缺血+二氮嗪治疗组和缺血+二氮嚷+MitoK(ATP)通道特异性抑制剂5-HD组。观察各组凋亡细胞数和凋亡相关蛋白Bcl-2、Bax的变化。结果与缺血组比较,二氮嗪使凋亡细胞数明显减少(83.2±9.04 vs 123.96±13.45),Bcl-2表达增高(0.17±0.01 vs 0.13±0.01),Bax表达下降(0.15±0.02 vs 0.20±0.03),差异具有显著性(P<0.05)。5-HD能取消这些作用(P<0.05)。结论局灶性脑缺血再灌注损伤时,二氮嗪能通过上调半暗带区Bcl-2蛋白表达,下调Bax蛋白表达,减少神经元凋亡,对脑缺血损伤起保护作用。 相似文献