Postural instability via a loss of intermittent control in elderly and patients with Parkinson's disease: A model-based and data-driven approach.

Postural instability is one of the major symptoms of Parkinson's disease. Here, we assimilated a model of intermittent delay feedback control during quiet standing into postural sway data from healthy young and elderly individuals as well as patients with Parkinson's disease to elucidate the possible mechanisms of instability. Specifically, we estimated the joint probability distribution of a set of parameters in the model using the Bayesian parameter inference such that the model with the inferred parameters can best-fit sway data for each individual. It was expected that the parameter values for three populations would distribute differently in the parameter space depending on their balance capability. Because the intermittent control model is parameterized by a parameter associated with the degree of intermittency in the control, it can represent not only the intermittent model but also the traditional continuous control model with no intermittency. We showed that the inferred parameter values for the three groups of individuals are classified into two major groups in the parameter space: one represents the intermittent control mostly for healthy people and patients with mild postural symptoms and the other the continuous control mostly for some elderly and patients with severe postural symptoms. The results of this study may be interpreted by postulating that increased postural instability in most Parkinson's patients and some elderly persons might be characterized as a dynamical disease.

Bright light improves sleep in patients with Parkinson's disease: possible role of circadian restoration.

Parkinson's disease (PD) is one of the most common neurodegenerative disorders. Among the most common manifestations of PD are sleep problems, which are coupled with the adverse effects of dopaminergic therapies (DT). A non-pharmacological solution for these sleep problems has been sought to avoid additional pharmacological intervention. Here, we show that bright light therapy (BLT) is effective for improving sleep in Japanese PD patients receiving DT. Furthermore, experimental evaluation of peripheral clock gene expression rhythms revealed that most PD patients receiving DT who experienced improved sleep following BLT showed a circadian phase shift, indicating the existence of a correlation between circadian modulation and sleep improvement. Conversely, this result indicates that sleep problems in PD patients receiving DT may arise at least in part as a result of circadian dysfunction. Indeed, we found that chronic dopaminergic stimulation induced a rapid attenuation of autonomous oscillations of clock gene expression in ex vivo cultured mouse suprachiasmatic nucleus (SCN) at the single neuron level. In conclusion, BLT is a promising medical treatment for improving sleep in PD patients receiving DT. This BLT-induced improvement may be due to the restoration of circadian function.

Bile acid abnormality induced by intestinal dysbiosis might explain lipid metabolism in Parkinson's disease.

Intestinal dysbiosis refers to an imbalance in the intestinal flora. The concept of small intestinal bacterial overgrowth (SIBO), a condition of abnormal proliferation of the small intestine microbiota, has been proposed as a form of small intestine dysbiosis. In Parkinson's disease patients, weight loss and metabolic disorders such as lipid abnormalities are frequently encountered. This was a prospective investigation of the presence of SIBO using the lactulose breath test, Parkinson's disease symptoms, medications, abdominal symptoms, and blood data involving 39 Parkinson's disease patients. Of the 39 patients, 19 were positive for SIBO, 16 were negative, and 4 were equivocal. SIBO-positive patients had a significantly smaller dopaminergic drug load (dopamine replacement of Parkinson's disease drug potency) (P = 0.009) and significantly lower serum triglyceride (TG) (P = 0.024) and total bilirubin (P = 0.019) levels. No relationship was seen between the presence or absence of SIBO and motor or abdominal symptoms. The following hypothesis was developed with regard to the possibility that intestinal bacterial overgrowth has various effects that are exhibited via bile acid metabolism in Parkinson's disease patients. Serum bilirubin levels become higher as bilirubin metabolism declines with decreases in the intestinal bacteria. At the same time, bile acid is broken down due to increased intestinal bacteria, and lipid absorption decreases. This induces low serum TG levels and leads to weight loss. By a similar mechanism, there is less absorption of vitamin D as bile acid levels decrease, leading to osteoporosis and fractures. The possibility that some of the non-motor manifestations accompanying Parkinson's disease are caused by intestinal dysbiosis needs to be considered.

Increased number of mitochondria in capillaries distributed in stroke-like lesions of two patients with MELAS.

We investigated two autopsy cases of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) using immunohistochemical staining with an anti-mitochondrial antibody against translocase of the outer membrane 20 (TOMM20). In case 1, the patient was a 42-year-old man with a disease duration of 53 days, and in case 2, the patient was a 62-year-old woman with a disease duration of 27 months. In both the cases autopsy revealed moderate atrophy of the cerebrum and cerebellum and multifocal necrotizing lesions, irrespective of the vascular territory. Case 1 showed multiple areas with total necrosis in the cortex, accompanied by increases in number of protoplasmic astrocytes and acidophilic neurons as well as axonal swelling, suggestive of acute or subacute stage stroke-like lesions (SLLs). In case 2, most of the SLLs displayed laminar spongy change in a rarefied cortex, and were considered to be at the chronic stage. In both the cases, capillary proliferation was noted within the SLLs, particularly in the acute phase. Endothelial cells of proliferating capillaries were strongly positive for TOMM20. In the cortex outside the SLLs, microvessels displayed only a fine granular immunoreactivity, as is seen in the controls. Although smooth muscle cells and endothelial cells in pial arteries and arterioles were also strongly positive for TOMM20, the territories of the affected pial arteries and arterioles did not correlate with the distribution of the SLLs. Although MELAS is characterized by recurrent stroke-like episodes (SLEs), the pathogenetic relationship between SLEs and mitochondrial angiopathy remains unknown. An aberrant increase of mitochondria in the capillary endothelial cells of SLLs may disturb endothelial function, thus playing a role in the formation or development of SLLs.

[Cerebral embolism in Duchenne muscular dystrophy after respiratory tract infection - Report of two cases].

We report cerebral embolism in 2 patients with Duchenne muscular dystrophy (DMD) after respiratory tract infection. A 31-year-old man (Case 1) was admitted to the hospital because of an upper respiratory tract infection, then suddenly developed left-sided hemiparesis. Transthoracic echocardiography revealed an intracardiac thrombus in the left ventricle, and, under assumption of cardioembolic stroke, oral anticoagulation was initiated. Case 2 was a 36-year-old man who developed dysphasia after increasing sputum. Based on brain CT scan findings, we confirmed a diagnosis of cerebral infarction. There was no recurrence in either case. Both cases developed cerebral infarction due to embolism after mild upper respiratory tract infections. DMD patients have various risk factors for thrombus and embolus, while physicians should also be aware of possible cerebral infarction and other coagulation disorders irrespective of respiratory and cardiac therapy.

GNE myopathy caused by a synonymous mutation leading to aberrant mRNA splicing.

GNE myopathy is a rare autosomal recessive myopathy caused by bi-allelic mutations in GNE. We report the case of a 36-year-old man who presented with typical clinical and pathological features of GNE myopathy including distal dominant muscle weakness from the age of 29 and numerous rimmed vacuoles on muscle biopsy. Targeted next-generation sequencing revealed a novel synonymous mutation, c.1500A>G (p.G500=), together with a common Japanese mutation c.620A>T (p.D207V). The cDNA analysis of the biopsied muscle revealed that this synonymous mutation creates a cryptic splice donor site that causes aberrant splicing. This report will expand our understanding of the genetic heterogeneity of GNE myopathy emphasizing the importance of interpreting synonymous variants in genetic testing.

A Pilot Study of Tranilast for Cardiomyopathy of Muscular Dystrophy.

Objective Heart failure is currently the most serious complication of muscular dystrophy. The transient receptor potential cation channel, subfamily V, member 2 (TRPV2) is a stretch-sensitive Ca channel. In damaged myocytes or cardiomyocytes, TRPV2 translocates to the cytoplasmic membrane and enhances Ca influx, triggering cell damage. Evidence suggests that the inhibition of TRPV2 may be a new therapeutic target in heart failure. We found that tranilast, which is widely used as an anti-allergic drug, inhibits TRPV2. A pilot study was conducted to assess the safety and efficacy of tranilast in muscular dystrophy patients with cardiomyopathy. Methods After obtaining informed consent, two muscular dystrophy patients with advanced heart failure took tranilast (300 mg/day) for three months. Blood tests, echocardiography, electrocardiography (ECG), Holter ECG, analyses of the TRPV2 expression in peripheral mononuclear cells, and circulating micro ribonucleic acid profiling were performed to assess the safety and efficacy of tranilast. Results The brain natriuretic peptide levels decreased after treatment. The expression of TRPV2 on the cytoplasmic membrane of peripheral mononuclear cells was enhanced before treatment and was decreased after treatment. Some heart-related micro ribonucleic acids (miR-208a-5p, miR-223-3p) were elevated and then decreased after treatment. Some adverse events, including the potentiation of warfarin, the worsening of renal dysfunction, an increased heart rate and premature ventricular contractions, were observed. Conclusion Tranilast can inhibit TRPV2 and can be effective for treating heart failure, even in patients with muscular dystrophy. Although careful attention is needed, the inhibition of TRPV2 can be a new treatment target for cardiomyopathy. A multi-center trial is planned.

Febuxostat ameliorates secondary progressive experimental autoimmune encephalomyelitis by restoring mitochondrial energy production in a GOT2-dependent manner.

Oxidative stress and mitochondrial dysfunction are important determinants of neurodegeneration in secondary progressive multiple sclerosis (SPMS). We previously showed that febuxostat, a xanthine oxidase inhibitor, ameliorated both relapsing-remitting and secondary progressive experimental autoimmune encephalomyelitis (EAE) by preventing neurodegeneration in mice. In this study, we investigated how febuxostat protects neuron in secondary progressive EAE. A DNA microarray analysis revealed that febuxostat treatment increased the CNS expression of several mitochondria-related genes in EAE mice, most notably including GOT2, which encodes glutamate oxaloacetate transaminase 2 (GOT2). GOT2 is a mitochondrial enzyme that oxidizes glutamate to produce α-ketoglutarate for the Krebs cycle, eventually leading to the production of adenosine triphosphate (ATP). Whereas GOT2 expression was decreased in the spinal cord during the chronic progressive phase of EAE, febuxostat-treated EAE mice showed increased GOT2 expression. Moreover, febuxostat treatment of Neuro2a cells in vitro ameliorated ATP exhaustion induced by rotenone application. The ability of febuxostat to preserve ATP production in the presence of rotenone was significantly reduced by GOT2 siRNA. GOT2-mediated ATP synthesis may be a pivotal mechanism underlying the protective effect of febuxostat against neurodegeneration in EAE. Accordingly, febuxostat may also have clinical utility as a disease-modifying drug in SPMS.

Brain micro-inflammation at specific vessels dysregulates organ-homeostasis via the activation of a new neural circuit.

Impact of stress on diseases including gastrointestinal failure is well-known, but molecular mechanism is not understood. Here we show underlying molecular mechanism using EAE mice. Under stress conditions, EAE caused severe gastrointestinal failure with high-mortality. Mechanistically, autoreactive-pathogenic CD4+ T cells accumulated at specific vessels of boundary area of third-ventricle, thalamus, and dentate-gyrus to establish brain micro-inflammation via stress-gateway reflex. Importantly, induction of brain micro-inflammation at specific vessels by cytokine injection was sufficient to establish fatal gastrointestinal failure. Resulting micro-inflammation activated new neural pathway including neurons in paraventricular-nucleus, dorsomedial-nucleus-of-hypothalamus, and also vagal neurons to cause fatal gastrointestinal failure. Suppression of the brain micro-inflammation or blockage of these neural pathways inhibited the gastrointestinal failure. These results demonstrate direct link between brain micro-inflammation and fatal gastrointestinal disease via establishment of a new neural pathway under stress. They further suggest that brain micro-inflammation around specific vessels could be switch to activate new neural pathway(s) to regulate organ homeostasis.

Study of Duchenne muscular dystrophy long-term survivors aged 40 years and older living in specialized institutions in Japan.

The national muscular dystrophy wards database of Japan lists 118 long-term Duchenne muscular dystrophy (DMD) patients who were at least 40 years old as of October 1, 2013. To elucidate the clinical features of DMD patients aged 40 years and older, we obtained gene analysis and muscle biopsy findings, as well as medical condition information. Ninety-four of the registered patients consented to participate, of whom 55 meeting genetic or biochemical criteria confirming DMD were analyzed. The mean age at the time of the study was 43.6 ± 3.0 years, while at the time of independent ambulation loss it was 10.6 ± 1.5 years and at mechanical ventilation introduction it was 24.1 ± 5.5 years. All were receiving continuous ventilation support, 27 with non-invasive positive pressure ventilation and 28 with tracheal intermittent positive pressure ventilation. Thirty-eight were receiving ß-blockers or a renin-angiotensin system inhibitor, while 9 were free from those agents. Forty had maintained oral nutrition. The 55 analyzed patients had survived into their 40s by receiving multidisciplinary intervention. Our findings emphasize the need of future studies to investigate disease modifiers and the mechanism of long-term survival. In addition, establishment of a worldwide care standard with focus on quality of life for adult males with DMD is important.

A case of Brugada syndrome which developed status epilepticus.

A 35-year-old man showed a convulsive attack with consciousness loss and was suspected of having Brugada syndrome 6 months prior to admission to our hospital. At the initial examination, the patient showed conjugate deviation, followed by left limb convulsions and consciousness loss. He regained consciousness after 1 minute, though cardiac arrest from ventricular fibrillation was noted during an electroencephalography (EEG) examination. Sinus rhythm recovered with defibrillation, though the convulsions persisted and a Status Epilepticus developed. The patient was diagnosed with Brugada syndrome and received implantable cardioverter defibrillator (ICD). After ICD, he has suffered no further convulsive attacks. Brugada syndrome is an inheritable cardiac disease causing sudden death by ventricular fibrillation. It is important to consider both epilepsy and arrhythmia in diagnosis of the seizures.

Renal dysfunction can be a common complication in patients with myotonic dystrophy 1.

Although renal failure can be a life-threatening complication even in neuromuscular disorders (NMDs), renal dysfunction is easily overlooked because muscle atrophy decreases the serum creatinine level. Renal function was retrospectively assessed using cystatin C (CysC) in various NMDs to clarify the differences among diseases. As is in the general population, age was correlated to CysC, and female patients showed lower CysC levels. Although elevated CysC was frequent in myotonic dystrophy 1 (DM1: MIM 160900) and motor neuron disorders, an inter-disease comparison by sex adjusted for age showed that only DM1 had a higher CysC compared to other diseases. Multivariate linear regression with the stepwise method also suggested that the number of CTG repeats had an impact on CysC levels. In two autopsy DM1 cases, nephrosclerotic changes were observed even though they were in their forties. These facts suggested a disease-specific pathomechanism for renal dysfunction in DM1. Although further study is required, renal function should be carefully monitored in patients with DM1.

High expression of α-synuclein in damaged mitochondria with PLA2G6 dysfunction.

To clarify the role of α-synuclein (αSyn) in neuronal membrane remodeling, we analyzed the expression of αSyn in neurons with a dysfunction of PLA2G6, which is indispensable for membrane remodeling. αSyn/phosphorylated-αSyn (PαSyn) distribution and neurodegeneration were quantitatively estimated in PLA2G6-knockout (KO) mice, which demonstrate marked mitochondrial membrane degeneration. We also assessed the relationship between αSyn deposits and mitochondria in brain tissue from patients with PLA2G6-associated neurodegeneration (PLAN) and Parkinson's disease (PD), and quantitatively examined Lewy bodies (LBs) and neurons. The expression level of αSyn was elevated in PLA2G6-knockdown cells and KO mouse neurons. Strong PαSyn expression was observed in neuronal granules in KO mice before onset of motor symptoms. The granules were mitochondrial outer membrane protein (TOM20)-positive. Ultramicroscopy revealed that PαSyn-positive granules were localized to mitochondria with degenerated inner membranes. After symptom onset, TOM20-positive granules were frequently found in ubiquitinated spheroids, where PαSyn expression was low. Axons were atrophic, but the neuronal loss was not evident in KO mice. In PLAN neurons, small PαSyn-positive inclusions with a TOM20-positive edge were frequently observed and clustered into LBs. The surfaces of most LBs were TOM20-positive in PLAN and TOM20-negative in PD brains. The high proportion of LB-bearing neurons and the preserved neuronal number in PLAN suggested long-term survival of LB-bearing neurons. Elevated expression of αSyn/PαSyn in mitochondria appears to be the early response to PLA2G6-deficiency in neurons. The strong affinity of αSyn for damaged mitochondrial membranes may promote membrane stabilization of mitochondria and neuronal survival in neurons.

Quantifying Parkinson's disease finger-tapping severity by extracting and synthesizing finger motion properties.

We propose a novel index of Parkinson's disease (PD) finger-tapping severity, called "PDFTsi," for quantifying the severity of symptoms related to the finger tapping of PD patients with high accuracy. To validate the efficacy of PDFTsi, the finger-tapping movements of normal controls and PD patients were measured by using magnetic sensors, and 21 characteristics were extracted from the finger-tapping waveforms. To distinguish motor deterioration due to PD from that due to aging, the aging effect on finger tapping was removed from these characteristics. Principal component analysis (PCA) was applied to the age-normalized characteristics, and principal components that represented the motion properties of finger tapping were calculated. Multiple linear regression (MLR) with stepwise variable selection was applied to the principal components, and PDFTsi was calculated. The calculated PDFTsi indicates that PDFTsi has a high estimation ability, namely a mean square error of 0.45. The estimation ability of PDFTsi is higher than that of the alternative method, MLR with stepwise regression selection without PCA, namely a mean square error of 1.30. This result suggests that PDFTsi can quantify PD finger-tapping severity accurately. Furthermore, the result of interpreting a model for calculating PDFTsi indicated that motion wideness and rhythm disorder are important for estimating PD finger-tapping severity.

Postural flexibility during quiet standing in healthy elderly and patients with Parkinson's disease.

Postural instability is one of the predominant symptoms of Parkinson's disease (PD). Despite its significant impact on the deterioration in quality of life in PD patients, mechanistic causes of the instability have not been clarified. Joint inflexibility at ankle and hip joints might be such a major cause, leading to small variability in the center of pressure (CoP) during quiet stance. However, this conjecture is still controversial. Thus, quantitative characterization of CoP patterns during quiet stance in PD patients remains a matter of research. Here we performed a linear discriminant analysis for CoP data in PD patients and age-matched healthy elderly during quiet stance, and showed that CoP variations in PD patients and those in healthy elderly could be well distinguished with an accuracy of about 90%, to which appropriately selected sway indices characterizing aspects of power spectrum for the CoP variations contributed. Specifically, major factors responsible for the discrimination were all associated with increase in the power at a high-frequency band (near and over 1 Hz) along with reduction at the low-frequency regime (lower than about 0.7 Hz). Then, the power-ratio, defined as the relative spectral power in a band around 1 Hz, was examined, since the power in this band reflects postural sway with anti-phase coordinated motions of the ankle and hip joints. We showed that the power-ratio values were significantly smaller in the PD patients than those in the healthy subjects. This difference as well as the results of the linear discriminant analysis suggest joint inflexibility in PD patients, particularly at hip joint, which diminished anti-phase coordination between trunk and lower extremity, leading to postural instability in PD patients.

Survivin expression in lung cancer: Association with smoking, histological types and pathological stages.

Survivin is expressed in the nucleus and/or cytoplasm of various malignant cells. Nuclear survivin is critical for the completion of mitosis, while cytoplasmic survivin functions as an inhibitor of apoptosis. The expression of survivin has been reported to be associated with the aggressiveness of certain types of cancer. The present study examined the association between cigarette smoking history and the expression of survivin and Ki-67 in lung adenocarcinomas of pathological (p) stages I, II and III. The expression of survivin and Ki-67 in adenocarcinomas was also compared with that of other p-stage I lung cancers, including squamous cell carcinoma (SqCC), large cell neuroendocrine carcinoma (LCNEC) and small cell carcinoma (SmCCs), of patients with a smoking history. In adenocarcinomas at p-stage I, labeling indices (LIs) of nuclear survivin and Ki-67 were significantly higher in tissue samples from smokers than those from non-smokers; however, the nuclear survivin and Ki-67 LIs in p-stage II and III adenocarcinomas from non-smokers and smokers were similar to those in p-stage I adenocarcinomas of smokers. The nuclear survivin and Ki-67 LIs in adenocarcinomas of smokers at p-stage I were lower than those in SqCCs, LCNECs and SmCCs of smokers at the same stage. Smokers with adenocarcinoma also exhibited a higher survival rate compared with that of smokers with SqCCs, LCNECs and SmCCs. The present results indicated that a history of smoking is associated with increased nuclear survivin and Ki-67 expression in lung adenocarcinomas of p-stage I, but not p-stages II or III. In addition it was revealed that, in smokers, the nuclear survivin and Ki-67 expression in p-stage I adenocarcinomas was lower than that of other p-stage I lung cancer types, and was associated with an enhanced survival rate. In conclusion, smoking is associated with the histogenesis of lung adenocarcinoma but not with the development of lung adenocarcinoma, based on the nuclear expression levels of Ki-67 and survivin.

A pain-mediated neural signal induces relapse in murine autoimmune encephalomyelitis, a multiple sclerosis model.

Although pain is a common symptom of various diseases and disorders, its contribution to disease pathogenesis is not well understood. Here we show using murine experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis (MS), that pain induces EAE relapse. Mechanistic analysis showed that pain induction activates a sensory-sympathetic signal followed by a chemokine-mediated accumulation of MHC class II+CD11b+ cells that showed antigen-presentation activity at specific ventral vessels in the fifth lumbar cord of EAE-recovered mice. Following this accumulation, various immune cells including pathogenic CD4+ T cells recruited in the spinal cord in a manner dependent on a local chemokine inducer in endothelial cells, resulting in EAE relapse. Our results demonstrate that a pain-mediated neural signal can be transformed into an inflammation reaction at specific vessels to induce disease relapse, thus making this signal a potential therapeutic target.

An autopsy case of neuronal intermediate filament inclusion disease with regard to immunophenotypic and topographical analysis of the neuronal inclusions.

We report an autopsy case of neuronal intermediate filament inclusion disease (NIFID), in which pyramidal motor dysfunction preceded cognitive disturbance for 3 years from the onset. A 41-year-old Japanese man presented progressive spastic tetraparesis followed by cognitive impairment. His neurological symptoms gradually deteriorated and he died of pneumonia 16 years from the onset. His brain showed severe generalized atrophy with enlargement of ventricles. The microscopic examination revealed severe neuronal loss with gliosis and sponginess predominantly in the fronto-temporal cortices, caudate and putamen. Many hyaline conglomerate inclusions (HC) without immunoreactivity for 'fused in sarcoma' protein (FUS) and some granular and small round FUS-immunoreactive (FUS-ir) neuronal cytoplasmic inclusions (NCI) were observed in the remaining neurons. Some neurons with HC had small basophilic inclusions which showed positive FUS-ir, attached to HC in the cytoplasm. Otherwise, FUS-ir large compact inclusions (so-called Pick-like) were also observed but were scarce. In the cerebral cortex and the neostriatum, frequency of the inclusions was well correlated with neuronal loss. In the brainstem, neuronal loss was mild and FUS-ir inclusions dominated. In the subthalamic nucleus and red nucleus, there was no HC but there were many FUS-ir inclusions without neuronal loss. The above findings suggest that cytoplasmic mislocalization and aggregation of FUS appear at the early stage of the disease, and the FUS aggregate process may not be a direct precedent structure of HC.

[Two cases of hereditary motor and sensory neuropathy with proximal dominant involvement (HMSN-P)].

We, herein, report two independent cases with hereditary motor and sensory neuropathy with proximal dominant involvement (HMSN-P) inherited in an autosomal dominant fashion. Their common clinical features are slowly progressive proximal dominant muscular atrophy, fasciculations and mild to moderate distal sensory disturbance with areflexia. Nerve conduction study revealed an absence of sensory nerve action potentials, in contrast to almost normal compound muscle action potentials. Gene analysis in both patients elucidated heterozygous mutation (c.854C>T, p.Pro285Leu) in the TFG, which is an identical mutation, already described by Ishiura et al. Okinawa and Shiga are two foci of HMSN-P in Japan. Eventually, one patient is from Okinawa and the other is from a mountain village in Shiga prefecture. When we see a patient who has symptoms suggestive of motor neuron disease with sensory neuropathy, HMSN-P should be considered as a differential diagnosis despite the patient's actual resident place.

Safety of a Pandemic Influenza Vaccine and the Immune Response in Patients with Duchenne Muscular Dystrophy.

OBJECTIVE: To examine the safety of and immune response to the influenza A(H1N1)pdm09 vaccine in patients with Duchenne muscular dystrophy (DMD). METHODS: Forty-four non-ambulatory patients with DMD hospitalized in a muscle disease ward and 41 healthy healthcare workers each received one dose of the influenza A(H1N1)pdm09 vaccine. Serum samples were collected before and four weeks after vaccination to measure the hemagglutinin inhibition antibody titers. RESULTS: No severe adverse events were noted in any of the subjects. The immune responses of the patients were comparable to those of the healthcare workers. Among the patients, tube feeding and a lower total protein level in the serum were identified to be significantly associated with a lower immune response. CONCLUSION: A single dose of the vaccine was found to be safe and induced an optimal level of immunity in the DMD patients. The nutritional status may be associated with the immune response in patients with DMD.