脂肪累积性肌肉病患者血浆左旋肉碱含量测定的意义

目的　讨论左旋肉碱测定在脂肪累积性肌肉病 (LSM)诊断及其病因分类和治疗监测方面的意义。方法　用酶学分析法对经肌肉活检证实的 8例LSM病人和其他 9例神经肌肉病病人 ,以及 18名正常对照进行血浆左旋肉碱测定。结果　 8例LSM病人的血浆左旋肉碱含量为 (4.4± 2 .5 )mg/L ;9例其他神经肌肉病病人为 (10 .2± 2 .5 )mg/L ;18例正常对照为 (11.8± 2 .9)mg/L。经方差分析 ,LSM组与正常对照组及其他神经肌肉病组相比 ,差异均有非常显著意义 (P <0 .0 0 1)。结论　血浆左旋肉碱测定是诊断脂肪累积性肌肉病的一种特异、灵敏的检测方法。     

硒蛋白-P在线粒体疾病患者不整红边纤维中的特异表达及相关作用

目的研究硒蛋白P与琥珀酸脱氢酶、细胞色素C氧化酶的关系及它们在线粒体疾病患者不整红边纤维(raggedredfiber,RRF)中的表现和作用。方法(1)研究对象:线粒体疾病患者14例,其中Kearns Sayre综合征患者1例,线粒体脑肌病、乳酸酸中毒伴卒中样症状者4例,肌阵挛癫伴RRF1例,慢性进行性眼外肌麻痹6例,肢带型线粒体病2例;5例对照,其中多发性肌炎2例,其他神经肌病3例。全部患者均经临床、病理、分子生物学DNA分析确诊。(2)开放式肌肉活检。(3)连续切片,经组织化学、免疫组织化学染色分析。结果患者RRF的肌浆中硒蛋白-P显著表达,琥珀酸脱氢酶活性增强,细胞色素C氧化酶活性增强、减弱或缺陷。结论硒蛋白-P在对抗线粒体氧化损伤、保护线粒体机能方面可能充当了重要角色,可以作为病理学评价线粒体机能和诊断RRF的指标。     

线粒体肌病伴脂质沉积

目的 :为了了解线粒体肌病与脂质累积性肌病的关系 ,我们观察了 2 9例线粒体肌病和 36例脂质累积性肌病的临床表现和肌肉病理改变 ,分析二者之间的异同和相互关系。方法 :应用组织学和组织化学方法 ,对 6 5线粒体肌病和脂质累积性肌病的肌肉活检标本进行观察。结果 :2 9例线粒体肌病或线粒体肌脑病肌肉活检中 ,12例伴有脂滴轻 -中度增多。 36例脂质累积性肌病中 ,绝大多数表现为单纯肌病 ,6例合并周围神经病 ,9例肌肉活检除脂滴大量堆积在纤维内以外 ,有不典型的 RRF。结论 :部分线粒体肌病和脂质累积性肌病的肌肉组织中可见线粒体异常和脂滴增多并存 ,说明线粒体异常会导致不同程度的脂肪代谢障碍。脂肪代谢障碍是导致肌肉无力的一个重要原因     

乳酸丙酮酸最小运动量试验在线粒体肌病临床检查中的应用

目的研究乳酸丙酮酸最小运动量试验(theminimum exercise test of lactic acid and pyruvic acid,METLP)在线粒体肌病诊断中的作用。方法选择我院神经生化实验室2005年1月至2008年11月进行METLP检查并且有病理结果证实的患者共67例,根据病理诊断,线粒体病组患者36例,非肌病组20例,对METLP的结果分析。结果非肌病组和线粒体病组的运动后即刻的乳酸和丙酮酸浓度均明显升高,但是休息10min后又逐渐恢复接近初始水平。而二者在运动同一阶段血液内乳酸和丙酮酸浓度比较,线粒体病组浓度明显高于非肌病组,差异有统计学意义(P0.05)。在线粒体病评判的各项指标中,L2/P1是敏感性最高的一项指标。然而,METLP对线粒体肌病的诊断也出现了一定的误诊和漏诊情况,漏诊率为7.46%,误诊率为4.48%。结论METLP在对线粒体肌病的初步筛选起到一定作用,其各项分析指标中,L2/P1是最重要的的一项。     

脂质沉积性肌病的临床与病理分析

目的探讨脂质沉积性肌病(lipidstoragemyopathy,LSM)的临床表现及病理学特点。方法回顾分析7例LSM的临床表现、肌电图及肌肉活检病理改变。结果LSM的主要临床特点为亚急性或慢性起病,近端肌无力,症状呈波动性,血清肌酶有不同程度的升高,多数病人肌电图示肌源性损害,激素治疗有效。病理学特点为肌纤维内可见大量均匀的小筛孔样空泡,部分空泡融合成大泡或形成裂隙状。ORO染色证实筛孔样空泡为大量红染的脂肪颗粒充填,部分肌纤维破裂,伴脂肪颗粒堆积。受累纤维以Ⅰ型纤维为主。电镜证实肌纤维内脂滴堆积,其中1例伴有异常线粒体增多。结论LSM是一种以易疲劳和肌无力为主要临床表现的脂质代谢障碍性肌病,激素治疗可获得良好疗效。肌肉活检病理学检查是诊断LSM的重要手段。     

乳酸和丙酮酸最小运动量试验对线粒体肌病的诊断价值

目的研究乳酸和丙酮酸最小运动量试验(METLP)对线粒体肌病的诊断价值。方法对肌肉病理明确诊断为线粒体肌病的21例患者、6例其他肌病患者及14例非肌病患者进行METLP检测,并对其检测结果进行分析。结果线粒体肌病组METLP 18例(85.7%)异常,12例≥2项指标异常,主要为运动后血浆乳酸/运动前丙酮酸(L2/P1)>17;其他肌病组METLP 6例(100%)异常,主要为有氧运动后血浆乳酸浓度(L2)升高,或者经休息其血浆乳酸浓度(L3)不降、甚至升高;非肌病组为3例(21.4%)异常。结论在METLP的各项评价指标中,L2/P1作为线粒体肌病与非肌病的诊断参考指标最为可靠;L3/L2可以作为鉴别线粒体肌病与其他肌病的可靠指标;但线粒体肌病的诊断应结合METLP、临床及病理综合分析。     

脂质沉积性肌病的临床与病理分析

目的 探讨脂质沉积性肌病(lipid storage myopathy，LSM)的临床表现及病理学特点。方法 回顾分析7例LSM的临床表现、肌电图及肌肉活检病理改变。结果 LSM的主要临床特点为亚急性或慢性起病，近端肌无力，症状呈波动性，血清肌酶有不同程度的升高，多数病人肌电图示肌源性损害，激素治疗有效。病理学特点为肌纤维内可见大量均匀的小筛孔样空泡，部分空泡融合成大泡或形成裂隙状。ORO染色证实筛孔样空泡为大量红染的脂肪颗粒充填，部分肌纤维破裂，伴脂肪颗粒堆积。受累纤雏以Ⅰ型纤雏为主。电镜证实肌纤维内脂滴堆积，其中1例伴有异常线粒体增多。结论 LSM是一种以易疲劳和肌无力为主要临床表现的脂质代谢障碍性肌病，激素治疗可获得良好疗效。肌肉活检病理学检查是诊断LSM的重要手段。     

脂质沉积性肌病二例

目的探讨脂质沉积性肌病(LSM)的临床和肌肉病理特点。方法分析2例LSM的临床特点、辅助检查及肌肉病理资料。结果 LSM的临床表现为进行性肌无力,以近端肌无力为主,伴肌萎缩;发作期血清肌酶轻、中度升高,血脂升高或正常,肌电图多为肌源性损害,合并神经源性损害;肌肉病理为I型纤维受累重,肌纤维内散在大小不等的圆形空泡或缺损(脂质颗粒),线粒体受压变形;对激素治疗反应好。结论临床表现和肌酶检查对LSM的诊断具有重要意义,确诊依靠肌肉病理活检,早期治疗效果好。     

脂质沉积性肌病1例报道

脂质沉积性肌病（1ipidstoragemyopathy，LsM）是由于影响脂质代谢的线粒体酶或肉碱缺乏，干扰了肌纤维内脂质代谢，导致肌细胞内脂肪堆积而引起的肌病，属常染色体隐性遗传肌病。肌肉中脂肪滴聚集是本病最显著的病理改变特点，不伴其他肌肉病理学改变。本研究报道1例LSM，从临床和病理角度进行分析，为诊断和治疗这类肌病提供参考，并结合文献初步进行分型分析。     

脂肪累积肌肉病的病理和肌电图改变之间的关系

目的探讨脂肪累积性肌肉病和线粒体脂肪累积性肌肉病的肌肉活检病理改变和肌电图改变之间的关系。方法对33例肌活检确诊患者的肌肉病理改变分为单纯脂肪累积性肌肉病和线粒体-脂肪累积性肌肉病两组,对比两者肌纤维内脂肪沉积的程度以及肌电图改变的差异。结果33.3%为线粒体-脂肪累积性肌肉病,66.7%为单纯脂肪累积性肌肉病。前者肌纤维内脂肪沉积程度显著,7例出现小组样分布的小角状萎缩的肌纤维,后者脂肪沉积的程度相对轻,只有3例患者出现小角状萎缩的肌纤维。在前者81.8%的患者肌电图为肌源性损害、18.2%为混合性损害、45.5%合并周围神经损害。在后者59.1%的患者出现肌源性损害、13.6%出现混合或神经源损害、27.3%肌电图正常、22.7%合并周围神经损害。结论和单纯脂肪累积性肌肉病比较,线粒体-脂肪累积性肌肉病的脂肪滴沉积程度更显著以及更多的患者出现肌纤维萎缩,更易导致骨骼肌的电生理改变以及合并周围神经损害。     

A morphometric study of muscle mitochondria in cytochrome c oxidase deficiency

Quantitative analysis of mitochondrial size and its percentage of total fibre volume in different muscle fibre types was performed on biceps brachii muscles of controls aged from 9 months to 10 years, and patients aged from 8 months to 14 years, with cytochrome c oxidase (CCO) deficiency confirmed by both histochemical and biochemical analyses. The disease was classified into 2 subgroups: one not containing ragged-red fibres (RRF) (group I), and one containing RRF (group II). Relationship between type 1 and 2 fibres in mitochondrial size and percentages of total fibre volume showed significant differences in the controls and group I. A comparison of the controls and group I did not show significant differences in mitochondrial size, but abnormally enlarged mitochondria were occasionally observed in the latter. In group I, statistical differences were observed in mitochondrial percentage of total fibre volume, though these differences remained in the control range, suggesting the presence of mild morphological changes in mitochondria on electron microscopy. In group II, mitochondrial size and its percentage of total fibre volume were markedly increased in both type 1 and 2 fibres, with no statistical differences observed between the 2 fibre types.     

原发性肉碱缺乏致脂质沉积性肌病的临床与病理特点

目的 分析原发性肉碱缺乏致脂质沉积性肌病（LSM）的临床与病理特点。方法 回顾性分析4例可能LSM患者的临床资料。结果 本组患者为亚急性或慢性起病，主要表现为近端肌无力，疲劳不能耐受；血清肌酶有不同程度的升高；肌电图示肌源性损害；病理检查示肌纤维内可见大量细小空泡和裂隙形成；MGT染色无破碎红纤维，油红O染色显示空泡为大量脂滴充填；受累纤维以Ⅰ型纤维为主。电镜证实肌纤维内脂滴堆积，可伴有线粒体的轻度增多。改善能量和糖皮质激素治疗有效。结论原发性肉碱缺乏致LSM是一种以易疲劳和肌无力为主要临床表现的脂质代谢障碍性肌病，病理改变以肌纤维内脂滴堆积为主，一般不伴有线粒体结构的明显异常。糖皮质激素治疗可获得良好疗效。     

Muscle carnitine deficiency and lipid storage myopathy in patients with mitochondrial myopathy

Abnormal carnitine distribution in muscle was found in 22 of 77 patients (29%), with mitochondrial myopathy. Furthermore, total (TC) and free (FC) carnitine levels in muscle were lower in patients than in controls (P < 0.01). Muscle long-chain acylcarnitines (LCAC) were significantly increased in these patients (P < 0.01). Muscle carnitine deficiency was found in 31.5% of patients with lipid storage myopathy (LSM) and in 25.6% of patients with ragged-red fibers (RRF). Therefore, carnitine deficiency can be found in patients with mitochondrial myopathy even in the absence of LSM. Muscle levels of TC and FC were lower in patients with respiratory chain defects than in those with normal respiratory chain (P < 0.01). In contrast, LCAC levels were significantly increased (P < 0.05). Carnitine levels did not differ significantly, among patients with different respiratory-chain defects. Consequently, these patients, owing to their biochemical block, reduce progressively the muscle carnitine pool and subsequent LCAC rise, due to long-chain fatty acid (LCFA) accumulation.     

Localization of mitochondrial DNA in normal and pathological muscle using immunological probes: a new approach to the study of mitochondrial myopathies.

We have studied the usefulness of anti-DNA antibodies to detect ragged-red fibers (RRF) in muscle biopsies from patients with mitochondrial myopathies. We have found that these antibodies are excellent probes for the localization of mitochondrial DNA (mtDNA) in RRF, and for the diagnosis of depletion of mtDNA in a newly described group of fatal myopathies of infancy.     

Study of mitochondrial DNA depletion in muscle by single-fiber polymerase chain reaction

We studied muscle biopsies from 3 children with a mitochondrial myopathy characterized histochemically by the presence of ragged-red fibers (RRF) and various numbers of cytochrome c oxidase (COX)-negative fibers. We quantitated the absolute amounts of total mitochondrial DNA (mtDNA) in isolated normal COX-positive muscle fibers and in COX-negative RRF. There was severe mtDNA depletion in all fibers from the two most severe cases. In the third case mtDNA depletion could not be established with conventional diagnostic tools, but it was documented in single COX-negative fibers; COX-positive fibers showed the same amounts of mtDNA as fibers from aged-matched controls. Our observations indicate that mtDNA single-fiber PCR quantitation is a highly sensitive and specific method for diagnosing cases with focal mtDNA depletion. This method also allows one to correlate amounts of mtDNA with histochemical phenotypes in individual fibers from patients and age-matched controls, thereby providing important information about the functional role of residual mtDNA. © 1998 John Wiley & Sons, Inc. Muscle Nerve 21: 1374–1381, 1998     

脂质沉积性肌病的临床和病理特点

目的从临床和肌肉病理的角度分析脂质沉积性肌病（ＬＳＭ）的特点。方法收集２０例ＬＳＭ病人的临床资料，并做肌肉活检，采用常规组织学方法和组织化学方法染色，并在电镜下观察。结果结合临床和病理特点可将病例分为两组，第一组为急性或亚急性起病，四肢近端肌无力，肌酶谱明显升高，对激素治疗敏感；第二组呈慢性迁延性病程，表现肌无力和对运动不耐受，对激素治疗不敏感，肌纤维内线粒体异常比较明显。对２０例病人的肌肉活检发现Ｉ型肌纤维为主的肌纤维空泡样变，油红“Ｏ”染色示脂滴明显增多，电镜也证实肌纤维内脂滴堆积，部分病例伴有异常线粒体增多。结论脂质沉积性肌病是一组生化方面十分复杂的疾病，属于线粒体肌病的一个类型，临床上以不能耐受运动和近端肌无力为主，病程呈波动性，部分可有自发缓解，肌肉病理检查有助于确诊。两组的临床病理差异可能提示脂肪代谢障碍的不同环节或不同酶的缺陷。     

Human muscle fiber fine structure: morphometric data on controls.

Muscle fiber fine structure was quantitatively analyzed in 70 longitudinally and 65 transversely sectioned fibers from 10 control subjects without weakness. The average mitochondrial fraction of the fiber volume is close to 4 percent and the mean size of a mitochondrion is about 0.1 mum2. The sarcotubular surface area per unit fiber volume is close to 1.5 mum2/mum3 in transverse sections and 0.65 times this value in longitudinal sections. Only one-third of all fibers contain lipid droplets in the sectioned plane, and for all fibers the droplets account for approximately 0.12 percent of the fiber volume. Variations with the age and sex of the subjects and with different muscles were analyzed and the feasibility of typing human muscle fibers at the ultrastructural level was evaluated.     

Single-fiber analysis of mitochondrial A3243G mutation in four different phenotypes

Five unrelated patients harboring the A3243G mutation in the mitochondrial DNA (mtDNA) but presenting with different clinical phenotype were studied for their percentage of mutation at the single muscle fiber levels. One patient had a clinically and pathologically defined Leigh syndrome (LS), two showed mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), another showed progressive external ophthalmoplegia (PEO), and the other showed mitochondrial diabetes mellitus (MDM). The mutation load was greater in the muscle from the patient with LS (92%), who showed more than 80% even in the non-ragged red fibers (RRF) and also presented the highest proportion of RRF. The patients with MELAS had lower mutation levels as well as a lower proportion of RRF, and these two parameters were even lower in the PEO and MDM patients. These results were consistent with the concept that differences in the mutation load and in the somatic distribution of the mutation among different cells and tissues are responsible for the differences in phenotypical expression of the disease. Received: 8 April 1999 / Revised, accepted: 28 June 1999     

Quantitative skeletal muscle pathology of aging regarding ragged-red fibers and cytochrome c oxidase-negative fibers]

A statistical analysis of mitochondrial abnormality of aging in human skeletal muscle fibers was performed. Sixty one muscle samples were obtained from patients with acute medical illness autopsied strictly within 2 hours after death, or with orthopedic or surgical diseases biopsied with informed consents. The patients aged from 16 to 89, averaging 58 +/- 21 years in males and 21 to 92, averaging 55 +/- 20 years in females. Sections were stained by modified Gomori's trichrome, succinate dehydrogenase and cytochrome c oxidase-negative [CCO(-)] fibers approximately in 10,000 fibers in each muscle were evaluated. Both RRF and CCO (-) fibers were not observed below the fourth decade, but sequentially increased with age, especially after the seventh decade. The incidence of CCO (-) fibers was higher than that of RRF. RRF did not necessarily correspond to CCO (-) fibers. The present quantitative pathological result is a useful tool to evaluate the mitochondrial function in fresh human skeletal muscles by the age.