先天性肌营养不良1A型的临床表现和病理改变（附1例报道）

目的：探讨先天性肌营养不良1A型的临床和病理特点。方法：回顾分析我院收治的1例先天性肌营养不良1A型轻症患者的临床表现和肌肉病理改变，并结合复习国内文献报道的5例病例。结果：患者均干出生后6个月内起病，多表现为新生儿肌张力低下，出生1年后头颅MRI均有特征性的白质改变，部分病例伴有关节挛缩、智能发育迟缓、癫痫和周围神经损害。肌肉病理均呈典型肌营养不良改变，伴Merosin蛋白完全缺失。结论：头颅MRI是先天性肌营养不良1A型的重要诊断依据，肌肉免疫组化对确诊尤为关键。     

Muscle imaging analogies in a cohort of patients with different clinical phenotypes caused by LMNA gene mutations

Laminopathies are a heterogeneous group of LMNA‐gene‐mutation–related clinical disorders associated with alterations of cardiac and skeletal muscle and peripheral nerves, metabolic defects, and premature aging. Leg muscle imaging investigations were performed in a cohort of patients with LMNA gene alterations who were suffering from Emery–Dreifuss muscular dystrophy, limb‐girdle muscular dystrophy type 1B, isolated cardiac disorders or a phenotype of cardiac disorders, and lipodystrophy, including one individual with peripheral neuropathy. Leg muscle imaging revealed varying degrees of alteration in the soleus and medial head of gastrocnemius in each subject. This study demonstrates that LMNA‐gene‐mutated patients devoid of any clinically detectable skeletal muscle involvement have the same pattern of leg muscle involvement as patients with overt skeletal muscle compromise. This finding suggests the presence of a continuum of skeletal muscle involvement among phenotypes of LMNA‐gene‐mutation–related skeletalmyopathy and cardiomyopathy. Muscle Nerve, 2010     

Stiffness of knee extensors in Duchenne Muscular Dystrophy

The series elastic component (SEC) of Hill's muscle model is sensitive to a modification in muscle functional demand. In this study, SEC stiffness was quantified from quick-released movements in knee extensors of Duchenne muscular dystrophy (DMD) boys to look for possible modifications with the stage of disease. A SEC stiffness index (SI) was defined and was found significantly lower for controls than for DMD. Moreover, a linear relationship was established between mean SI and knee extensors involvement. This suggests a role for this parameter, together with other functional tests, for following patients with DMD. © 1998 John Wiley & Sons, Inc. Muscle Nerve 21: 1772–1774, 1998     

Two children with "dropped head" syndrome due to lamin A/C mutations

LMNA-related congenital muscular dystrophy (L-CMD) is a recently described disorder characterized by infantile-onset myopathy due to mutations in the lamin A/C (LMNA) gene. We report the genetic and clinical characteristics of two unrelated L-CMD patients. Patient 1 harbored a novel, L35P mutation and patient 2 a previously reported R249W mutation. The striking phenotype associated with L-CMD is important to recognize, as molecular diagnostic testing can spare patients unnecessary procedures and prompt the physician to monitor for associated cardiac arrhythmias.     

面肩肱型肌营养不良患者伴发视网膜病变的相关研究进展

面肩肱型肌营养不良（FSHD）是一种临床表现多样的遗传性肌病。除累及肌肉外，还累及全身多个系统，其中视网膜病变常被忽视。约1％的FSHD患者因未能及时发现视网膜血管病变而导致最终失明。FSHD伴发视网膜病变，如类似Coats病血管改变的机制尚不明确，普遍认为此两者存在必然联系。多数学者建议对FSHD患者进行早期眼底检查，必要时作眼底荧光血管造影术，以便早期诊断、早期治疗视网膜病变，减少失明率。着眼于发病机制，尤其是致病基因定位的研究，以及在明确基因突变位点后寻找相应的调控物质或抑制转录分子将是今后的研究热点。     

A novel LMNA gene mutation Leu162Pro and the associated clinical characteristics in a family with autosomal-dominant emery-dreifuss muscular dystrophy

We report the clinical characteristics, genetic analysis, and muscle biopsy findings of a family with Emery-Dreifuss muscular dystrophy and a novel mutation (Leu162Pro) in the LMNA gene. Within this single family, the age of onset and disease severity varied among the family members. In addition, focal defects of nuclear membranes with chromatin blebs in endothelial cells was shown via electron microscopy.     

One Year Outcome of Boys With Duchenne Muscular Dystrophy Using the Bayley-III Scales of Infant and Toddler Development

BackgroundThe pathogenesis of Duchenne muscular dystrophy starts before birth. Despite this, clinical trials exclude young boys because traditional outcome measures rely on cooperation. We recently used the Bayley-III Scales of Infant and Toddler Development to study 24 infants and boys with Duchenne muscular dystrophy. Clinical evaluators at six centers were trained and certified to perform the Bayley-III. Here, we report 6- and 12-month follow-up of two subsets of these boys.PatientsNineteen boys (1.9 ± 0.8 years) were assessed at baseline and 6 months. Twelve boys (1.5 ± 0.8 years) were assessed at baseline, 6, and 12 months.ResultsGross motor scores were lower at baseline compared with published controls (6.2 ± 1.7; normal 10 ± 3; P < 0.0001) and revealed a further declining trend to 5.7 ± 1.7 (P = 0.20) at 6 months. Repeated measures analysis of the 12 boys monitored for 12 months revealed that gross motor scores, again low at baseline (6.6 ± 1.7; P < 0.0001), declined at 6 months (5.9 ± 1.8) and further at 12 months (5.3 ± 2.0) (P = 0.11). Cognitive and language scores were lower at baseline compared with normal children (range, P = 0.002-<0.0001) and did not change significantly at 6 or 12 months (range, P = 0.89-0.09). Fine motor skills, also low at baseline, improved >1 year (P = 0.05).ConclusionDevelopment can reliably be measured in infants and young boys with Duchenne muscular dystrophy across time using the Bayley-III. Power calculations using these data reveal that motor development may be used as an outcome measure.     

序贯式干细胞移植术治疗假肥大型肌营养不良症临床研究

目的：观察假肥大型肌营养不良症（PMD）患儿接受序贯式干细胞移植术（SCT）后抗肌萎缩蛋白（dystrophin）的表达、dystrophin基因和运动功能的变化。方法：采用自身对照法,2008年2月至2010年11月对5例8～14岁男性PMD患儿接受序贯式SCT[即依次进行脐带间充质干细胞（UCMSC）经静脉内移植-UCMSC肌肉内移植-单倍体相合造血干细胞移植术（Haplo-HSCT）]治疗,观察患儿血清酶学、基因分析、肌电图、肌肉活检及肌萎缩蛋白、造血重建的植入证据的变化。结果：移植后①血清肌酸激酶数值显著降低;②PCR-STR检测4例为完全供者型嵌合,1例3/6位点相合患儿未植入为完全受者型;③4例外显子缺失患儿外周血及骨髓表达正常基因型;④肌肉活检显示供受者嵌合状态,缺失的外显子弱阳性表达。肌细胞形态改善,肌萎缩蛋白间断弱阳性表达;⑤肌力及运动功能较治疗前无减退或改善。结论：PMD患儿接受序贯式SCT后缺失的外显子转变为正常基因型,肌细胞膜有肌萎缩蛋白阳性或弱阳性表达,可提高患儿的运动功能。     

Congenital muscular dystrophy with dropped head phenotype and cognitive impairment due to a novel mutation in the LMNA gene

Mutations in A-type nuclear lamins are known to cause a variety of diseases, which can affect almost all organs of the human body including striated muscle. For lamin-related congenital muscular dystrophy two different phenotypes are known to date. Here, we describe a 3-year-old, white Caucasian girl with a novel de novo mutation in the LMNA gene with marked hypotonia of neck and trunk muscles with dropped head posture, loss of cervical lordosis and marked joint laxity. In addition to this novel mutation, the patient also had cerebral white matter lesions on MRI and cognitive impairment on developmental testing. This is only the second A-type lamin-related congenital muscular dystrophy patient in which white matter lesions are described. Thus, white matter involvement might be a feature in A-type lamin-related congenital muscular dystrophy, warranting screening of these patients for both white matter lesions and cognitive impairment.     

肌型肌酸激酶同工酶亚型在早期诊断假肥大型肌营养不良中的价值

目的 研究假肥大型肌营养不良（DMD）患者肌型肌酸激酶（CK－MM）亚型的变化,为早期诊断和正确评价病情提供依据。方法 采用不连续缓冲体系,在稳流低压条件下电泳分离CK－MM型亚,荧光扫描。结果 随着DMD患者病情的加重,其不同阶段的MM2／MM1均与对照组差异显著（P＜0．05）,DMD患者不同阶段的MM2／MM1值差异也显著（P＜0．05）,结论 CK－MM亚型的改变是DMD的早期诊断指标,是判断病情及科学评价治疗效果的依据。     

Fukuyama-type congenital muscular dystrophy: a case report in the Japanese population living in Brazil

INTRODUCTION: We present herein clinical, histological and magnetic resonance imaging (MRI) findings in a patient with Fukuyama-type congenital muscular dystrophy (FCMD). He is the first case report in the Japanese population living in Brazil. CASE REPORT: The child presented with neonatal hypotonia, delayed motor abilities and speech, seizures, cerebral and cerebellar gyrus abnormalities with signal intensity change in the white matter by MRI, high serum level of creatinephosphokinase (CK), and dystrophic skeletal muscle with normal merosin, alpha-sarcoglycan and dystrophin expression. The fukutin gene study showed one founder 3-kb retrotransposal insertion in the 3'-non-coding region, and in the other allele no mutation was detected after screening all exons and flanking introns by sequencing. DISCUSSION: This case report emphasizes the importance to consider FCMD in Japanese people living in other countries.     

Congenital muscular dystrophy phenotype with neuromuscular spindles excess in a 5-year-old girl caused by HRAS mutation

We report on a 5-year-old girl who presented with an association of symptoms reminiscent of an Ullrich-like congenital muscular dystrophy including congenital hypotonia, proximal joint contractures, hyperlaxity of distal joints, normal cognitive development, and kyphoscoliosis. There was an excess of neuromuscular spindles on the skeletal muscle biopsy. This very peculiar feature on muscle biopsy has been reported only in patients with mutations in the HRAS gene. Sequence analysis of the subject’s HRAS gene from blood leukocytes and skeletal muscle revealed a previously described heterozygous missense mutation (c.187G>A, p. Glu63Lys). The present report thus extends the differential diagnosis of congenital muscular dystrophy with major “retractile” phenotypes and adds congenital muscular dystrophy to the clinical spectrum of HRAS-related disorders.     

Risk Factors for Cerebral Infarction in Duchenne Muscular Dystrophy: Review With our 2 Cases

Background: Although the incidence of cerebral infarction is higher in Duchenne muscular dystrophy (.75 per 100) than in the general population (7.5-11.4 per 100 000), only 18 cases have been reported, and prevention and management guidelines for infarction in this disorder remain lacking. Patients and Methods: We encountered 2 cases of Duchenne muscular dystrophy with cerebral infarction. To clarify risk factors for such infarction in Duchenne muscular dystrophy, we reviewed 20 cases, including our 2 patients. Results: Age at onset of infarction ranged from 4 to 31 years (n = 19). Most patients were 16-21 years old (14 of 19; 73.7%). Eighteen patients (90%) had dilated cardiomyopathy (DCM), showing a higher frequency than in the age-matched general Duchenne muscular dystrophy population. Left ventricular ejection fraction (LVEF) ranged from 10.2% to 42% (median, 20%; n = 9). Detectable cardiac thrombus and atrial fibrillation were rare (2 of 17; 11.8%, and 1 of 17; 5.9%, respectively). Conclusions: Presence of DCM with low LVEF seems to be the strongest risk factor for cerebral infarction in Duchenne muscular dystrophy.     

A point mutation in the glycerol kinase gene associated with a deletion in the dystrophin gene in a familial X-linked muscular dystrophy: non-contiguous gene syndrome involving Becker muscular dystrophy and glycerol kinase loci

We report a family with an X-linked recessive muscular dystrophy characterised by exercise-induced myalgia, recurrent pigmenturia and mild proximal muscle involvement. Immunocytochemical and immunoblotting analysis in muscle, using the antibody directed against the rod domain of dystrophin, revealed a loss of immunoreactivity, but the immunolabelling using the antibodies directed against the COOH and NH₂ domains of dystrophin were almost normal. The immunoreactions for -sarcoglycan, γ-sarcoglycan and β-dystroglycan were normal. In the five male patients of this family with increased serum creatine kinase levels (from ×8 to ×50), mass spectrometry screening of the urine revealed a large increase in glycerol elimination which was quantified by enzymatic assay (from ×14 to ×39). An in-frame deletion of the dystrophin gene (exons 13–29) was found in the same five males and in three carrier females. All the deleted chromosomes also carried a missense mutation at nucleotide 947 of the Xp glycerol kinase (GK) gene resulting in a Thr to Met substitution at codon 278. These findings indicate that the two mutations cosegregate on the same chromosome in this family. This is the first reported case of two physically independent mutations, within the DMD and GK genes, which are contiguous but several hundred kilobases apart.     

Effective Treatment With Albuterol in DOK7 Congenital Myasthenic Syndrome in Children

BackgroundCongenital myasthenic syndromes consist of rare disorders resulting from mutations in genes encoding for presynaptic, synaptic, and postsynaptic proteins that are involved in the signal transmission of the neuromuscular junction. They are characterized by fatigable weakness of the skeletal muscles with symptom onset from birth to early childhood. DOK7 (downstream of tyrosine kinase 7) congenital myasthenic syndrome was previously treated successfully with ephedrine and salbutamol; however, both are unavailable in the United States.MethodsCase report of a child with muscle weakness.ResultsThis report describes a boy who presented only with progressive limb-girdle muscle weakness since age 2 years. The muscle biopsy with extensive studies revealed no obvious etiologies. His muscle weakness rapidly worsened, requiring a wheelchair for daily activities. Expanded neuromuscular gene panel promptly led to the diagnosis of DOK7 congenital myasthenic syndrome, and his muscle strength dramatically and persistently improved in four weeks with albuterol treatment, allowing him to walk independently. In a brief literature review, 15 patients (five treated between ages 5 and 17 years) from the Mayo Clinic with DOK7 mutations were also successfully treated with albuterol.ConclusionDOK7 congenital myasthenic syndrome often presents with limb-girdle muscle weakness, which can become progressive without proper treatment. If muscle biopsy reveals no obvious etiology, an expanded neuromuscular gene panel may lead to a specific diagnosis of congenital myasthenic syndrome such as those due to DOK7 mutation. Albuterol is often used to treat bronchial asthma; however, it can also dramatically and persistently improve the muscle strength of DOK7 congenital myasthenic syndrome.