Synthetic Utilization of 2H-Heptafluoropropane: Ionic 1,4-Addition to Electron-Deficient Carbon-Carbon Unsaturated Bonds.

We have found a novel method for introducing heptafluoro-2-propyl CF(CF3)2 groups into carbon-carbon unsaturated bonds via a nucleophilic reaction using 2H-heptafluoropropane as the source of CF(CF3)2 groups. The reaction involves the nucleophilic addition of a heptafluoro-2-propyl anion, generated by treating 2H-heptafluoropropane with a fluoride ion, to various electron-deficient unsaturated compounds. This allows the easy synthesis of various aliphatic compounds containing heptafluoro-2-propyl groups.

Biallelic Mutations in MYPN, Encoding Myopalladin, Are Associated with Childhood-Onset, Slowly Progressive Nemaline Myopathy.

Nemaline myopathy (NM) is a common form of congenital nondystrophic skeletal muscle disease characterized by muscular weakness of proximal dominance, hypotonia, and respiratory insufficiency but typically not cardiac dysfunction. Wide variation in severity has been reported. Intranuclear rod myopathy is a subtype of NM in which rod-like bodies are seen in the nucleus, and it often manifests as a severe phenotype. Although ten mutant genes are currently known to be associated with NM, only ACTA1 is associated with intranuclear rod myopathy. In addition, the genetic cause remains unclear in approximately 25%-30% of individuals with NM. We performed whole-exome sequencing on individuals with histologically confirmed but genetically unsolved NM. Our study included individuals with milder, later-onset NM and identified biallelic loss-of-function mutations in myopalladin (MYPN) in four families. Encoded MYPN is a sarcomeric protein exclusively localized in striated muscle in humans. Individuals with identified MYPN mutations in all four of these families have relatively mild, childhood- to adult-onset NM with slowly progressive muscle weakness. Walking difficulties were recognized around their forties. Decreased respiratory function, cardiac involvement, and intranuclear rods in biopsied muscle were observed in two individuals. MYPN was localized at the Z-line in control skeletal muscles but was absent from affected individuals. Homozygous knockin mice with a nonsense mutation in Mypn showed Z-streaming and nemaline-like bodies adjacent to a disorganized Z-line on electron microscopy, recapitulating the disease. Our results suggest that MYPN screening should be considered in individuals with mild NM, especially when cardiac problems or intranuclear rods are present.

Molecular epidemiology and clinical spectrum of hereditary spastic paraplegia in the Japanese population based on comprehensive mutational analyses.

Hereditary spastic paraplegia (HSP) is one of the most genetically heterogeneous neurodegenerative disorders characterized by progressive spasticity and pyramidal weakness of lower limbs. Because >30 causative genes have been identified, screening of multiple genes is required for establishing molecular diagnosis of individual patients with HSP. To elucidate molecular epidemiology of HSP in the Japanese population, we have conducted mutational analyses of 16 causative genes of HSP (L1CAM, PLP1, ATL1, SPAST, CYP7B1, NIPA1, SPG7, KIAA0196, KIF5A, HSPD1, BSCL2, SPG11, SPG20, SPG21, REEP1 and ZFYVE27) using resequencing microarrays, array-based comparative genomic hybridization and Sanger sequencing. The mutational analysis of 129 Japanese patients revealed 49 mutations in 46 patients, 32 of which were novel. Molecular diagnosis was accomplished for 67.3% (33/49) of autosomal dominant HSP patients. Even among sporadic HSP patients, mutations were identified in 11.1% (7/63) of them. The present study elucidated the molecular epidemiology of HSP in the Japanese population and further broadened the mutational and clinical spectra of HSP.

CTG repeat length underlying cardiac events and sudden death in myotonic dystrophy type 1.

Aims: Myotonic dystrophy Type 1 (DM1) is caused by the expansion of CTG repeats (CTGn) in the DM1 protein kinase (DMPK) gene, while it remains unclear whether CTGn may be associated with the incidence of cardiac events or sudden death in Japan as well as Europe. The aim of this study was to investigate the association between CTGn and cardiac involvements. Methods and results: This cohort study included patients with DM1 who were retrospectively recruited from nine Japanese hospitals specializing in neuromuscular diseases. A total of 496 patients with DM1 who underwent a genetic test in the DMPK gene were analysed. Patients with congenital form or under 15 years old were excluded and patients were assigned into the quartiles. When we compared the incidence of cardiac events including advanced/complete atrioventricular block, pacemaker implantation, and ventricular tachycardias or mortality among four groups, patients with 1300 or longer CTGn experienced composite cardiac events [hazard ratio (HR): 3.19, 95% confidence interval (CI): 1.02-9.99, P = 0.014] more frequently and had significantly higher mortality rate (HR: 6.79, 95% CI: 2.05-22.49, P < 0.001) than those under 400 CTGn while the rate of sudden death was not significantly different. Conclusion: Regarding the cardiac events and mortality in patients with DM1, patients with 1300 or longer CTGn are at especially high risk.

Complex hereditary peripheral neuropathies caused by novel variants in mitochondrial-related nuclear genes.

Mitochondrial disorders are a group of clinically and genetically heterogeneous multisystem disorders and peripheral neuropathy is frequently described in the context of mutations in mitochondrial-related nuclear genes. This study aimed to identify the causative mutations in mitochondrial-related nuclear genes in suspected hereditary peripheral neuropathy patients. We enrolled a large Japanese cohort of clinically suspected hereditary peripheral neuropathy patients who were mutation negative in the prescreening of the known Charcot-Marie-Tooth disease-causing genes. We performed whole-exome sequencing on 247 patients with autosomal recessive or sporadic inheritance for further analysis of 167 mitochondrial-related nuclear genes. We detected novel bi-allelic likely pathogenic/pathogenic variants in four patients, from four mitochondrial-related nuclear genes: pyruvate dehydrogenase beta-polypeptide (PDHB), mitochondrial poly(A) polymerase (MTPAP), hydroxyacyl-CoA dehydrogenase/3-ketoacyl-CoA thiolase/enoyl-CoA hydratase, beta subunit (HADHB), and succinate-CoA ligase ADP-forming beta subunit (SUCLA2). All these patients showed sensory and motor axonal polyneuropathy, combined with central nervous system or multisystem involvements. The pathological analysis of skeletal muscles revealed mild neurogenic changes without significant mitochondrial abnormalities. Targeted screening of mitochondria-related nuclear genes should be considered for patients with complex hereditary axonal polyneuropathy, accompanied by central nervous system dysfunctions, or with unexplainable multisystem disorders.

[Changing medical care for amyotrophic lateral sclerosis patients and cause of death - review of muscular dystrophy wards (1999-2013)].

We analyzed the records of inpatients with amyotrophic lateral sclerosis (ALS) treated at 27 specialized institutions for muscular dystrophy in Japan from 1999 to 2013 registered in a database on October 1 of each year. The total number of ALS inpatients in 1999 was 29, then that showed rapid increases in 2006 and 2007, and reached 164 in 2013. Age regardless of year was predominantly greater than 50 years. In 1999, the respirator dependent rate was 68.9% and then increased to 92.7% in 2013, while the oral nutritional supply rate was 41.4% in 1999 and decreased to 10.4% in 2013. The number of deaths from 2000 to 2013 was 118. Cause of death was respiratory failure in 26 of 30 patients who maintained voluntary respiration at the time of death and in 5 of 6 with non-invasive ventilation. On the other hand, the main cause of death in patients with tracheostomy invasive ventilation was respiratory infection, which was noted in 26 of 82, while other causes varied. It is expected that the number of ALS patients admitted to specialized institutions with muscular dystrophy wards will continue to increase.

[An experience of administration of modafinil for excessive daytime sleepiness in a patient with myotonic dystorophy].

We report the beneficial and adverse effects of modafinil for daytime sleepiness in a 62-year-old female patient with myotonic dystrophy. Although it was effective for excessive daytime sleepiness, orolingual dyskinesia appeared the day following administration of modafinil (100 mg/day), and dyskinesia disturbed her daily life including dental treatment. When modafinil was stopped, dyskinesia was improved. However, excessive daytime sleepiness deteriorated gradually; re-treatment with smaller dosage (50 mg every other day) resulted in partial improvement but aggravation of both dyskinesia and diabetes mellitus. Modafinil should be administered carefully when the patient is older or has complications such as glucose intolerance.

Cardiac Conduction Disorders as Markers of Cardiac Events in Myotonic Dystrophy Type 1.

Background Myotonic dystrophy type 1 involves cardiac conduction disorders. Cardiac conduction disease can cause fatal arrhythmias or sudden death in patients with myotonic dystrophy type 1. Methods and Results This study enrolled 506 patients with myotonic dystrophy type 1 (aged ≥15 years; >50 cytosine-thymine-guanine repeats) and was treated in 9 Japanese hospitals for neuromuscular diseases from January 2006 to August 2016. We investigated genetic and clinical backgrounds including health care, activities of daily living, dietary intake, cardiac involvement, and respiratory involvement during follow-up. The cause of death or the occurrence of composite cardiac events (ie, ventricular arrhythmias, advanced atrioventricular blocks, and device implantations) were evaluated as significant outcomes. During a median follow-up period of 87 months (Q1-Q3, 37-138 months), 71 patients expired. In the univariate analysis, pacemaker implantations (hazard ratio [HR], 4.35; 95% CI, 1.22-15.50) were associated with sudden death. In contrast, PQ interval ≥240 ms, QRS duration ≥120 ms, nutrition, or respiratory failure were not associated with the incidence of sudden death. The multivariable analysis revealed that a PQ interval ≥240 ms (HR, 2.79; 95% CI, 1.9-7.19, P<0.05) or QRS duration ≥120 ms (HR, 9.41; 95% CI, 2.62-33.77, P < 0.01) were independent factors associated with a higher occurrence of cardiac events than those observed with a PQ interval <240 ms or QRS duration <120 ms; these cardiac conduction parameters were not related to sudden death. Conclusions Cardiac conduction disorders are independent markers associated with cardiac events. Further investigation on the prediction of occurrence of sudden death is warranted.

[Nasal flaring during hypoxemia in myotonic dystrophy and duchenne muscular dystrophy].

We investigated the relationship between nasal flaring and SpO2 in 19 patients with Duchenne muscular dystrophy (DMD) and 26 patients with myotonic dystrophy (DM1). In DMD patients, nasal flaring was observed when SpO2 was lower than 96%, while it was not seen even at 82% of SpO2 in DM1. None of the DM1 patients could perform voluntary nasal flaring. Nasal flaring is a useful indicator of hypoxemia in DMD but not in DM1. It remains to be elucidated whether the lack of nasal flaring in DM1 patients is due to abnormal respiratory central mechanism or nasal muscle weakness.

[Inpatients with facioscapulohumeral muscular dystrophy in specialized institutions in Japan from 1999 to 2013-Clinical condition changes and causes of death].

We analyzed the registration data of inpatients with facioscapulohumeral muscular dystrophy (FSHD) receiving care at 27 specialized institutions for muscular dystrophy in Japan from 1999 to 2013 using data from October 1 of each year. The number of inpatients of each year ranged from 63 to 72 (67.1 ± 3.3) throughout the study period. Those aged over 50 years gradually increased during the study period, while the oldest inpatient was 82.8 years old. Most could not walk. The rate of respirator dependency increased from 21.0% in 1999 to 71.0% in 2013, while the rate of patients receiving oral nutrition was 98.4% in 1999 and then reduced to 75.4% in 2013. There were 36 death cases reported in the database, including 15 patients with respiratory failure and 4 with heart failure. Our findings indicate that FSHD patients in a severe condition are impacted by respiratory and nutritional problems and their prognosis for survival is related to respiratory failure.

Duchenne muscular dystrophy in a female with compound heterozygous contiguous exon deletions.

Females with Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) mutations rarely exhibit clinical symptoms from childhood, although potential mechanisms for symptoms associated with DMD and BMD in females have been reported. We report the case of a female DMD patient with a clinical course indistinguishable from that of a male DMD patient, and who possessed compound heterozygous contiguous exon deletions in the dystrophin gene. She exhibited Gowers' sign, calf muscle hypertrophy, and a high serum creatine kinase level at 2 years. Her muscle pathology showed most of the fibers were negative for dystrophin immunohistochemical staining. She lost ambulation at 11 years. Multiplex ligation-dependent probe amplification analysis of this gene detected one copy of exons 48-53; she was found to be a BMD carrier with an in-frame deletion. Messenger RNA from her muscle demonstrated out-of-frame deletions of exons 48-50 and 51-53 occurring on separate alleles. Genomic DNA from her lymphocytes demonstrated the accurate deletion region on each allele. To our knowledge, this is the first report on a female patient possessing compound heterozygous contiguous exon deletions in the dystrophin gene, leading to DMD.

A Japanese male with a novel ANO5 mutation with minimal muscle weakness and muscle pain till his late fifties.

Limb girdle muscular dystrophy type 2L (LGMD2L) is an adult-onset slowly progressive muscular dystrophy associated with anoctamin 5 (ANO5) gene mutation, mainly reported from Northern and Central Europe. We report the case of a Japanese male patient with a novel homozygous mutation of c.2394dup, p.Arg799Thrfs in ANO5 gene, the second patient in the Asian population. He had had marked elevation of creatine kinase (CK) level for more than 10 years with minimal muscular symptoms consisting of muscle stiffness and occasional cramps, preceding the onset of proximal limb weakness. Calf hypertrophy and selective fatty replacement of the adductor magnus and gastrocnemius muscles were prominent clinical and muscle imaging features. This case suggests that LGMD2L may affect a broader population than has been previously thought, physicians should consider the possibility of ANO5 mutation even in patients showing elevated CK level with no apparent muscle weakness but muscle stiffness or cramps.

Lhermitte's sign in alcoholic myelopathy without portosystemic shunting: MRI evaluation.

We conducted spinal MR imaging on a 35-year-old man with Lhermitte's sign that had manifested over the previous 4 years. He had consumed more than 500 ml of whisky daily for at least 10 years. However, he did not show any evidence of severe liver disease with hepato-systemic blood shunting. Neurologic examination revealed markedly depressed sense of vibration in the feet and mild spasticity in the lower limbs, together with Lhermitte's sign. MR imaging revealed abnormal signal intensity in the posterior column spanning the whole length of the upper cervical cord, which is consistent with Lhermitte's sign.

The characteristics of camptocormia in patients with Parkinson's disease: A large cross-sectional multicenter study in Japan.

PURPOSE: The goal of the present study was to clarify the clinical characteristics and laboratory results of parkinsonian symptoms among patients with and without camptocormia. METHODS: Seventy-eight Parkinson's disease (PD) patients with camptocormia and 78 PD patients without camptocormia underwent a neurological examination, a blood test, and spinal magnetic resonance imaging (MRI). PD with camptocormia group and PD with non-camptocormia group were matched on age, age at PD onset, and sex. PRINCIPAL RESULTS: Camptocormia group had significantly higher prevalence of compression fractures, more severe parkinsonian symptoms, and a greater incidence of dementia than those without camptocormia. Serum creatine kinase levels in camptocormia group significantly elevated compared with non-camptocormia group. There were higher prevalence of abnormal findings in spine MRI including compression fractures and paravertebral muscle changes in camptocormia group compared with non-camptocormia group. MAJOR CONCLUSIONS: Camptocormia is associated with a greater prevalence of compression fractures and associated with greater UPDRS part II, part III score, axial score, and lower MMSE in this cross-sectional study. Thus, it can be concluded that camptocormia in PD is predominantly myopathic.

Brain volume analyses and somatosensory evoked potentials in multiple system atrophy.

We investigated a progression of brain atrophy and somatosensory system dysfunction in multiple system atrophy (MSA). Subjects were 21 MSA patients [12 MSA-C (cerebellar type) and 9 MSA-P (parkinsonism type)]. The relative volumes of cerebrum, brainstem and cerebellum to the intracranial volume were obtained from three-dimensional computed tomography (3D-CT) of the brain. The median nerve somatosensory evoked potentials (SEPs) were recorded, and the latencies and amplitudes of N9, N11, P13/14, N20 and P25 components were measured. We studied correlations between brain volumes, SEP and clinical features. The brainstem and cerebellar atrophies were aggravated with progression of the disease. The central sensory conduction time (CSCT) was progressively prolonged in parallel with the disease duration irrespective of the actual age of the patients. In MSA patients, the volume reductions of cerebellum and brainstem could be one of structural markers of disease progression, and the sensory pathway is progressively involved with the progression of disease processes.

Asymptomatic sporadic dysferlinopathy presenting with elevation of serum creatine kinase. Typical distribution of muscle involvement shown by MRI but not by CT.

We report an 18-year-old man with elevation of the creatine kinase (CK) level to 11,068 IU/L. There was no muscle atrophy or fat replacement on CT while muscles in the posterior compartment of lower legs showed high T2 signal intensity on MRI. We performed muscle biopsy from the gastrocnemius muscle. Immunohistochemical analysis demonstrated an absence of dysferlin leading to a diagnosis of preclinical dysferlinopathy. Typical distribution of muscle involvement was demonstrated not by CT but by MRI which may have contributed to facilitating diagnosing the earliest stage of preclinical dysferlinopathy, presenting with asymptomatic elevation of serum creatine kinase.

Mental retardation and lifetime events of Duchenne muscular dystrophy in Japan.

OBJECTIVE: This study investigated the relationship between mental retardation and lifetime events in patients with Duchenne muscular dystrophy (DMD). METHODS: The data on mental retardation and ages of lifetime events (first walking, loss of ambulation, introductions of ventilator support and tube nutrition and death) were collected retrospectively, and the relationships between the factors were analyzed. PATIENTS: Among 194 DMD patients admitted to our hospital between 1995 and 2007, 74 patients underwent evaluation of their intelligence quotient (IQ). RESULTS: Twenty-eight patients (38%) demonstrated mental retardation (IQ<70). DMD patients with mental retardation started walking later, required ventilator and tube nutrition support earlier, and died earlier than those without mental retardation. CONCLUSIONS: Since the prognosis of DMD patients with mental retardation was worse than that of those without mental retardation, more careful treatment is necessary for DMD patients with mental retardation.

Heart rate variability and hypercapnia in Duchenne muscular dystrophy.

OBJECTIVE: To investigate the relationship between heart rate variability and hypercapnia. PATIENTS AND METHODS: We measured the coefficient of variation of R-R interval (CVrr) and arterial blood gas pressures in 73 patients with Duchenne muscular dystrophy. RESULTS: CVrr was negatively correlated with arterial partial pressure of carbon dioxide (PaCO(2)). In patients whose CVrr was larger than 5%, 84% of them had no hypercapnia while the other 16% had hypercapnia (PaCO(2) >45 mmHg). In contrast, 27% of those with CVrr smaller than 3% had no hypercapnia, 73% had hypercapnia and 47% had severe hypercapnia (PaCO(2) >50 mmHg). CONCLUSION: We first showed that CVrr was negatively correlated with PaCO(2), and propose that abnormally low CVrr indicates respiratory insufficiency in patients with Duchenne muscular dystrophy.