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Importance Repeat expansion of CGG in LRP12 has been identified as the causative variation of oculopharyngodistal myopathy (OPDM). However, to our knowledge, the clinicopathologic features of OPDM with CGG repeat expansion in LRP12 (hereafter referred to as OPDM_LRP12) remain unknown. Objective To identify and characterize the clinicopathologic features of patients with OPDM_LRP12. Design, setting, and participants This case series included 208 patients with a clinical or clinicopathologic diagnosis of oculopharyngeal muscular dystrophy (OPDM) from January 1, 1978, to December 31, 2020. Patients with GCN repeat expansions in PABPN1 were excluded from the study. Repeat expansions of CGG in LRP12 were screened by repeat primed polymerase chain reaction and/or Southern blot. Main outcomes and measures Clinical information, muscle imaging data obtained by either computed tomography or magnetic resonance imaging, and muscle pathologic characteristics. Results Sixty-five Japanese patients with OPDM (40 men [62%]; mean [SD] age at onset, 41.0 [10.1] years) from 59 families with CGG repeat expansions in LRP12 were identified. This represents the most common OPDM subtype among all patients in Japan with genetically diagnosed OPDM. The expansions ranged from 85 to 289 repeats. A negative correlation was observed between the repeat size and the age at onset (r2 = 0.188, P = .001). The most common initial symptoms were ptosis and muscle weakness, present in 24 patients (37%). Limb muscle weakness was predominantly distal in 53 of 64 patients (83%), but 2 of 64 patients (3%) had predominantly proximal muscle weakness. Ptosis was observed in 62 of 64 patients (97%), and dysphagia or dysarthria was observed in 63 of 64 patients (98%). A total of 21 of 64 patients (33%) had asymmetric muscle weakness. Aspiration pneumonia was seen in 11 of 64 patients (17%), and 5 of 64 patients (8%) required mechanical ventilation. Seven of 64 patients (11%) developed cardiac abnormalities, and 5 of 64 patients (8%) developed neurologic abnormalities. Asymmetric muscle involvement was detected on computed tomography scans in 6 of 27 patients (22%) and on magnetic resonance imaging scans in 4 of 15 patients (27%), with the soleus and the medial head of the gastrocnemius being the worst affected. All 42 muscle biopsy samples showed rimmed vacuoles. Intranuclear tubulofilamentous inclusions were observed in only 1 of 5 patients. Conclusions and relevance This study suggests that OPDM_LRP12 is the most frequent OPDM subtype in Japan and is characterized by oculopharyngeal weakness, distal myopathy that especially affects the soleus and gastrocnemius muscles, and rimmed vacuoles in muscle biopsy.

Background Complement is likely to have a role in refractory generalised myasthenia gravis, but no approved therapies specifically target this system. Results from a phase 2 study suggested that eculizumab, a terminal complement inhibitor, produced clinically meaningful improvements in patients with anti-acetylcholine receptor antibody-positive refractory generalised myasthenia gravis. We further assessed the efficacy and safety of eculizumab in this patient population in a phase 3 trial. Methods We did a phase 3, randomised, double-blind, placebo-controlled, multicentre study (REGAIN) in 76 hospitals and specialised clinics in 17 countries across North America, Latin America, Europe, and Asia. Eligible patients were aged at least 18 years, with a Myasthenia Gravis-Activities of Daily Living (MG-ADL) score of 6 or more, Myasthenia Gravis Foundation of America (MGFA) class II-IV disease, vaccination against Neisseria meningitides, and previous treatment with at least two immunosuppressive therapies or one immunosuppressive therapy and chronic intravenous immunoglobulin or plasma exchange for 12 months without symptom control. Patients with a history of thymoma or thymic neoplasms, thymectomy within 12 months before screening, or use of intravenous immunoglobulin or plasma exchange within 4 weeks before randomisation, or rituximab within 6 months before screening, were excluded. We randomly assigned participants (1:1) to either intravenous eculizumab or intravenous matched placebo for 26 weeks. Dosing for eculizumab was 900 mg on day 1 and at weeks 1, 2, and 3; 1200 mg at week 4; and 1200 mg given every second week thereafter as maintenance dosing. Randomisation was done centrally with an interactive voice or web-response system with patients stratified to one of four groups based on MGFA disease classification. Where possible, patients were maintained on existing myasthenia gravis therapies and rescue medication was allowed at the study physician's discretion. Patients, investigators, staff, and outcome assessors were masked to treatment assignment. The primary efficacy endpoint was the change from baseline to week 26 in MG-ADL total score measured by worst-rank ANCOVA. The efficacy population set was defined as all patients randomly assigned to treatment groups who received at least one dose of study drug, had a valid baseline MG-ADL assessment, and at least one post-baseline MG-ADL assessment. The safety analyses included all randomly assigned patients who received eculizumab or placebo. This trial is registered with ClinicalTrials.gov, number NCT01997229. Findings Between April 30, 2014, and Feb 19, 2016, we randomly assigned and treated 125 patients, 62 with eculizumab and 63 with placebo. The primary analysis showed no significant difference between eculizumab and placebo (least-squares mean rank 56·6 [SEM 4·5] vs 68·3 [4·5]; rank-based treatment difference -11·7, 95% CI -24·3 to 0·96; p=0·0698). No deaths or cases of meningococcal infection occurred during the study. The most common adverse events in both groups were headache and upper respiratory tract infection (ten [16%] for both events in the eculizumab group and 12 [19%] for both in the placebo group). Myasthenia gravis exacerbations were reported by six (10%) patients in the eculizumab group and 15 (24%) in the placebo group. Six (10%) patients in the eculizumab group and 12 (19%) in the placebo group required rescue therapy. Interpretation The change in the MG-ADL score was not statistically significant between eculizumab and placebo, as measured by the worst-rank analysis. Eculizumab was well tolerated. The use of a worst-rank analytical approach proved to be an important limitation of this study since the secondary and sensitivity analyses results were inconsistent with the primary endpoint result; further research into the role of complement is needed. Funding Alexion Pharmaceuticals.

The terminal complement inhibitor eculizumab was shown to improve myasthenia gravis-related symptoms in the 26-week, phase 3, randomized, double-blind, placebo-controlled REGAIN study (NCT01997229). In this 52-week sub-analysis of the open-label extension of REGAIN (NCT02301624), eculizumab's efficacy and safety were assessed in 11 Japanese and 88 Caucasian patients with anti-acetylcholine receptor antibody-positive refractory generalized myasthenia gravis. For patients who had received placebo during REGAIN, treatment with open-label eculizumab resulted in generally similar outcomes in the Japanese and Caucasian populations. Rapid improvements were maintained for 52 weeks, assessed by change in score from open-label extension baseline to week 52 (mean [standard error]) using the following scales (in Japanese and Caucasian patients, respectively): Myasthenia Gravis Activities of Daily Living (-2.4 [1.34] and - 3.3 [0.65]); Quantitative Myasthenia Gravis (-2.9 [1.98] and - 4.3 [0.79]); Myasthenia Gravis Composite (-4.5 [2.63] and - 4.9 [1.19]); and Myasthenia Gravis Quality of Life 15-item questionnaire (-8.6 [5.68] and - 6.5 [1.93]). Overall, the safety of eculizumab was consistent with its known safety profile. In this interim sub-analysis, the efficacy and safety of eculizumab in Japanese and Caucasian patients were generally similar, and consistent with the overall REGAIN population. ispartof: JOURNAL OF THE NEUROLOGICAL SCIENCES vol:407 ispartof: location:Netherlands status: published

The spleen plays an important role in the body’s immune defense against invasive infections, particularly those caused by encapsulated bacteria. Encapsulated bacterial infection in asplenic patients is a medical emergency called overwhelming postsplenectomy infection (OPSI) and has a mortality rate of 50–70%. Here, we report the case of a 51-year-old Asian man who complained of emesis and diarrhea as primary symptoms. He rapidly progressed to coma and was eventually diagnosed with OPSI (pyogenic ventriculitis/spondylitis) caused by non-vaccine pneumococcal serotype 23A. Aggressive management, including empiric antibiotic therapy, a staircase approach for intracranial pressure-targeted therapy and laminectomy/laminoplasty, resulted in a good recovery. Our report highlights that non-vaccine pneumococcal serotypes can cause disease in vaccinated patients.

Alzheimer's disease (AD) is a common neurodegenerative disease that progressively impairs memory and cognition. Deposition of amyloid-β (Aβ) peptides is the most important pathophysiological hallmark of AD. Oxidative stress induced by generation of reactive oxygen species (ROS) is a prominent phenomenon in AD and known to occur early in the course of AD. Several reports suggest a relationship between change in redox status and AD pathology including progressive Aβ deposition, glial cell activation, and inflammation. Galantamine is an acetylcholinesterase inhibitor and has been reported to have an oxidative stress inhibitory function. In the present study, galantamine was administered orally to AD model mice from before the appearance of Aβ plaques (preplaque phase), and in vivo change in redox status of the brain was measured using electron paramagnetic resonance (EPR) imaging. Administration of galantamine from the preplaque phase ameliorated memory decline in Morris water maze test and novel object recognition test. Monitoring of the redox status of the brain using EPR imaging showed that galantamine treatment improved the unbalanced redox state. Additionally, galantamine administration enhanced microglial function to promote Aβ clearance, reducing the Aβ-positive area in the cortex and amount of insoluble Aβ in the brain. In contrast, galantamine treatment from the preplaque phase suppressed the production of proinflammatory cytokines through neurotoxic microglial activity. Therefore, galantamine administration from the preplaque phase may have the potential of clinical application for the prevention of AD. In addition, our results demonstrate the usefulness of EPR imaging for speedy and quantitative evaluation of the efficacy of disease-modifying drugs for AD.

Alzheimer's disease (AD) is one of the most common neurodegenerative diseases responsible for progressive dementia. Deposition of amyloid-β (Aβ) in the brain is the most important pathophysiological hallmark of AD. In addition, recent evidence indicates that reactive oxygen species (ROS) derived from mitochondria contribute to progression of AD pathology. We thus hypothesized that Aβ accumulates and oxidative stress increases in the brain mitochondria of a transgenic mouse model of AD (APdE9). We measured the quantity of Aβ and the activity of the antioxidant enzyme superoxide dismutase (SOD) in brain mitochondrial fractions prepared from APdE9 and wild-type (WT) mice aged 6, 9, 15, and 18 months. We also quantified the age-related changes in redox status in the mitochondrial fractions obtained from both APdE9 and WT mouse brains by electron paramagnetic resonance (EPR) spectrometry using a paramagnetic nitroxide "Mito-Tempo" [(2-(2,2,6,6-Tetramethylpiperidin-1-oxyl-4-ylamino)-2-oxoethyl) triphenylphosphonium chloride monohydrate] as a mitochondria-targeted redox-sensitive probe. In APdE9 mice, Aβ accumulated in brain mitochondria earlier than in the non-mitochondrial fraction of the brain. Furthermore, increased oxidative stress was demonstrated in brain mitochondria of APdE9 mice by in vitro SOD assay as well as EPR spectroscopy. EPR combined with a mitochondria-targeted redox-sensitive nitroxide probe is a potentially powerful tool to elucidate the etiology of AD and facilitate the development of new therapeutic strategies for AD.

ObjectivesMultiple system atrophy (MSA) is a refractory neurodegenerative disease, but novel treatments are anticipated. An accurate natural history of MSA is important for clinical trials, but is insufficient. This regional registry was launched to complement clinical information on MSA.SettingPatient recruitment started in November 2014 and is ongoing at the time of submission. The number of participating facilities was 66. Postal surveys were sent to medical facilities and patients with MSA in Hokkaido, Japan.ParticipantsAfter obtaining written consent from 196 participants, 184 overview surveys and 115 detailed surveys were conducted.Primary and secondary outcome measuresAn overview survey evaluated conformity to diagnostic criteria and a detailed survey implemented an annual assessment based on the Unified Multiple System Atrophy Rating Scale (UMSARS).ResultsAt the time of registration, 58.2% of patients were diagnosed with cerebellar symptoms predominant type MSA (MSA-C) and 29.9% were diagnosed with parkinsonism predominant type MSA (MSA-P). UMSARS Part Ⅳ score of 4 or 5 accounted for 53.8% of participants. The higher the UMSARS Part Ⅳ score, the higher the proportion of MSA-P. At baseline, levodopa was used by 69 patients (37.5%) and the average levodopa dose was 406.7 mg/day. The frequency of levodopa use increased over time. Eleven cases changed from MSA-C to MSA-P during the study, but the opposite was not observed. Information about survival and causes of death was collected on 54 cases. Half of deaths were respiratory-related. Sudden death was recorded even in the group with UMSARS Part Ⅳ score of 1.ConclusionsThis study is the first large-scale prospective MSA cohort study in Asia. MSA-C was dominant, but the use of antiparkinsonian drugs increased over the study period. Changes from MSA-C to MSA-P occurred, but not vice versa.

Fused - in - sarcoma ( FUS ) mutation is associated with a familial amyotrophic lateral sclerosis (fALS) characterized by early onset and rapid progression. Here, the authors describe a rare case of possible somatic mosaicism of a novel FUS variant for a fALS family with intrafamilial clinical variablity.

In response to changes of the central nervous system environment, microglia are capable of acquiring diverse phenotypes for cytotoxic or immune regulation and resolution of injury. Alzheimer's disease (AD) pathology also induces several microglial activations, resulting in production of pro-inflammatory cytokines and reactive oxygen species or clearance of amyloid-β (Aβ) through phagocytosis. We previously demonstrated that microglial activation and increase in oxidative stress started from the middle age in APPswe/PS1dE9 mice, and hypothesized that M1 activation occurs in middle-aged AD mice by Aβ stimulation. In the present study, we analyzed in vivo expressions of pro-inflammatory cytokines (M1 microglial markers), M2 microglial markers, and suppressor of cytokine signaling (SOCS) family, and examined the microglial phenotypic profile in APPswe/PS1dE9 mice. Then we compared the in vitro gene expression patterns of Aβ- and lipopolysaccharide (LPS)-stimulated primary-cultured microglia. Microglia in APPswe/PS1dE9 mice exhibited an M1-like phenotype, expressing tumor necrosis factor α (TNFα) but not interleukin 6 (IL6). Aβ-stimulated primary-cultured microglia also expressed TNFα but not IL6, whereas LPS-stimulated primary-cultured microglia expressed both pro-inflammatory cytokines. Furthermore, both microglia in APPswe/PS1dE9 mice and Aβ-stimulated primary-cultured microglia expressed SOCS3. Reduction of SOCS3 expression in Aβ-challenged primary-cultured microglia resulted in upregulation of IL6 expression. Our findings indicate that SOCS3 suppresses complete polarization to M1 phenotype through blocking IL6 production, and Aβ-challenged primary-cultured microglia replicate the in vivo gene expression pattern of microglia in APPswe/PS1dE9 mice. Aβ may induce the M1-like phenotype through blocking of IL6 by SOCS3.

Fingolimod is a sphingosine-1-phosphate receptor agonist used to inhibit the inflammatory activity of multiple sclerosis (MS), and has been shown to suppress osteoporosis in mouse models. In this study, levels of bone turnover markers were quantified in serum and urine samples from MS patients treated with fingolimod. Compared with untreated MS patients and healthy controls, fingolimod-treated MS patients had a significantly lower level of the bone resorption marker type I collagen cross-linked N-telopeptide in urine. This finding was prominent in female but was not seen in male subjects. Our results suggest that fingolimod may have a beneficial effect on bone mass loss in female MS patients.

Polyglutamine (polyQ) diseases comprise neurodegenerative disorders caused by expression of expanded polyQ-containing proteins. The cytotoxicity of the expanded polyQ-containing proteins is closely associated with aggregate formation. In this study, we report that a novel J-protein, DNAJ (HSP40) Homolog, Subfamily C, Member 8 (DNAJC8), suppresses the aggregation of polyQ-containing protein in a cellular model of spinocerebellar ataxia type 3 (SCA3), which is also known as Machado-Joseph disease. Overexpression of DNAJC8 in SH-SY5Y neuroblastoma cells significantly reduced the polyQ aggregation and apoptosis, and DNAJC8 was co-localized with the polyQ aggregation in the cell nucleus. Deletion mutants of DNAJC8 revealed that the C-terminal domain of DNAJC8 was essential for the suppression of polyQ aggregation, whereas the J-domain was dispensable. Furthermore, 22-mer oligopeptide derived from C-termilal domain could suppress the polyQ aggregation. These results indicate that DNAJC8 can suppress the polyQ aggregation via a distinct mechanism independent of HSP70-based chaperone machinery and have a unique protective role against the aggregation of expanded polyQ-containing proteins such as pathogenic ataxin-3 proteins.

A 61-year-old alcoholic man was admitted to our hospital because of disturbance of consciousness. He also exhibited external ophthalmoplegia, diplopia and mild rigidity, but tendon reflex was normal. On brain MRI, diffusion weighted images (DWI) and apparent diffusion coefficient (ADC) map depicted high intensity in the splenium of the corpus callosum. DWI showed high intensity, but ADC map depicted iso-intensity in bilateral precentral gyri. Marchiafava-Bignami disease (MBD) was diagnosed. After intravenous drip of vitamin, his symptoms improved rapidly and the abnormal MRI findings in the splenium of the corpus callosum and bilateral precentral gyri disappeared gradually. MBD is pathologically characterized by demyelination and necrosis in the corpus callosum, which are generally caused by cytotoxic edema. Our case suggests that vasogenic edema may occur at the early stage of the MBD.

A 57-year-old man initially developed chest discomfort, nausea, vomiting, headache and low-grade fever, followed by paraplegia, sensory disturbance below level Th5 and bilateral visual loss. He was admitted to our hospital on the 15th day of illness. MRI short T1 inversion recovery image showed multiple longitudinal lesions in the spinal cord below C3, and T2-weighted image showed abnormal hyperintensity within the left optic nerve. Cerebrospinal fluid (CSF) analysis revealed marked pleocytosis (1,719/μl) and hypoglycorrhachia (CSF glucose; 20 mg/dl). Intensive immunosuppressive therapy combined with antibiotics and antiviral agent were started immediately, resulting in relatively good visual outcome but no improvement of paraplegia and sensory disturbance. The patient's serum sample on admission was subsequently reported to be positive for anti-aquaporin-4 antibody. With no evidence of infectious diseases, neuromyelitis optica (NMO) was diagnosed. It should be borne in mind that marked hypogylcorrhachia may also be seen in NMO.

A 55-year-old man was admitted to our hospital because of acute onset of diplopia and gait disturbance. On admission, ophthalmoplegia, ataxia and areflexia were observed. He was diagnosed with Fisher syndrome and given intravenous immunoglobulin therapy from day 6 to day 10 after disease onset. After treatment, ophthalmoplegia and ataxia began to improve. However, he developed taste impairment on day 13 and right hemifacial weakness on day 16 after onset. A blink reflex test revealed right facial nerve impairment. On day 42 after onset, facial weakness and taste impairment remitted, and the blink reflex test result was normalized without additional treatment. Although it has been known that 10% of patients with Fisher syndrome complicated by delayed facial nerve palsy, the mechanism of the facial nerve palsy has not been elucidated. Therefore, this is a significant report to describe delayed facial nerve palsy combined with taste impairment and successive recordings of blink reflex and facial nerve conduction in a patient with Fisher syndrome.

Introduction. The aim of this study is to elucidate the impairment of excitation-contraction (E-C) coupling in ICU-acquired weakness (ICUAW) using a unique electrophysiologic method in patients received the intensive care in ICU. Methods. We examined 13 patients with ICUAW and 11 normal controls. We performed successive recordings of electrophysiological tests after ICU admission. First, CMAPs of abductor hallucis muscle (AH) and sural SNAPs were recorded using a conventional method. In addition, the tibial nerve was stimulated at the popliteal fossa using a supramaximal rectangular pulse to record CMAPs from soleus muscle (SOL). Simultaneously, movement- related potential (MRP) was recorded using an accelerometer (SV1101; NEC, Tokyo Japan) taped at the base of hallux and calculated E-C coupling time (ECCT) based on the latency differences between soleus CMAP and MRP. Results. We recorded significantly decreased CMAP amplitudes in 6 AHs and 8 SOLs and significantly longer CMAP durations in 2 SOLs. Also, we recorded significantly decreased MRPs in 9 patients and significantly prolonged ECCTs in 10 patients. These abnormal findings were detected even in very short durations of ICU stay such as 2-3 days. The durations of ICU stay seemed to be correlated with involvement of CMAP amplitudes of AH/SOL, MRPs and ECCTs. Ten patients showed decreased SOL-CMAP amplitude concomitant with decreased MRP and/or prolonged ECCT in spite of preservation of SOL-CMAP duration. In addition, CMAP amplitudes of AH/SOL and MRP were significantly smaller in patients than in controls. Furthermore, CMAP durations of AH and ECCTs were significantly longer in patients than in controls. Conclusion. The E-C coupling may be impaired in the very early stages of CIM. Noninvasive measurement of MRP and ECCT is easy to perform, and may be useful to detect the impairment of E-C coupling in the early stages of ICUAW.

A 57-year-old man with atherosclerosis obliterans was admitted with sudden-onset sensory aphasia and right hemiparesis. Brain MRI revealed acute cerebral infarctions in the left temporal lobe and magnetic resonance angiography showed occlusion of the posterior branch of the left middle cerebral artery. Transesophageal echocardiography and ultrasonography respectively confirmed a patent foramen ovale and deep vein thrombosis in the bilateral femoral veins. Blood findings showed low protein S antigen, low protein S activity, and a missense mutation of the PROS 1 gene. The administration of apixaban 10 mg BID prevented ischemic stroke recurrence and decreased the deep vein thrombosis. These outcomes indicated that apixaban may be alternative to warfarin for the secondary prevention of ischemic stroke in a patient with a protein S deficiency.

Background Recurrent ischemic stroke early after administration of intravenous tissue plasminogen activator (IV t-PA) is a rare complication. Most previously reported cases have shown poor prognosis with only speculations regarding reasons for recurrence. Case description We report a case of recurrent cerebral infarction due to atrial fibrillation early after IV t-PA in a 77-year-old woman. She presented with sudden neurological deterioration 86 min after IV t-PA. Magnetic resonance imaging demonstrated new ischemic stroke with right internal carotid artery occlusion. Endovascular thrombectomy improved her prognosis and we evaluated the left atrial appendage using transesophageal echocardiography. Conclusions Attention should be paid to ischemic stroke recurrence as a complication of IV t-PA, and preparation for mechanical thrombectomy is warranted. Further study of the left atrial appendage is needed to clarify the mechanisms of onset.

Background: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that affects the upper and lower motor neurons. Currently, only riluzole and edaravone are approved as drugs to treat ALS and new agents with larger effect sizes are warranted. Exploratory analyses in our previous study (study ID #E0302-J081-761) have suggested that high-dose methylcobalamin (E0302) prolonged the overall survival of ALS patients and suppressed ALS progression in patients with a disease duration of less than 12 months. Objective: This clinical trial aims to evaluate the efficacy and safety of E0302 for treatment of ALS patients within one year of onset. Methods: The Japanese early-stage trial of high-dose methylcobalamin for ALS (JETALS) is a prospective, multicenter, placebo-controlled, double-blind, randomized phase III study conducted at 24 tertiary neurology centers and is funded by the Japan Agency for Medical Research and Development. A total of 128 ALS patients within one year of onset were randomized at a 1:1 ratio to receive intramuscular injection with E0302 50 mg or placebo twice a week for 16 weeks. The primary endpoint is changes in the ALS Functional Rating Scale-Revised (ALSFRS-R) total score at 16 weeks. If patients wish to receive E0302 50 mg after the double-blind administration period, E0302 will be provided to them until March 2020 during the continuous administration period. Results: This study began in October 2017 and is being conducted at 24 participating institutions in Japan. The study is in progress and the patient enrollment period is scheduled to end in August 2019, with follow-up scheduled to end in March 2020. Conclusions: This study is being performed to revalidate the efficacy and safety of E0302 in patients with early-stage ALS in the first year of symptom onset. If positive results are obtained, the aim is to apply for E0302 approval as a new drug for the treatment of ALS. Trial Registration: ClinicalTrials.gov NCT03548311; https://clinicaltrials.gov/ct2/show/NCT03548311 (Archived by WebCite at http://www.webcitation.org/74Fw3rDzb) International Registered Report Identifier (IRRID): PRR1-10.2196/12046

The patient in Case 1 was a 25-year-old female nurse. While she was working at a day-care, she fell down shortly after using a barcode reader. This was followed by a tonic-clonic seizure. The seizure spontaneously stopped after approximately 5 minutes. However, consciousness impairment continued for about 30 minutes. The patient in Case 2 was a 30-year-old female nurse. During the night shift at her workplace, she found it impossible to stand up after staring at the red flashing lights from a barcode reader. The patient was also disoriented, as indicated by her inability to recall her colleague's name. The patient's condition gradually improved and she became fully conscious soon after the episode. We believe that the barcode reader led to photosensitivity in both cases. Barcode readers that emit red flashing lights are thought to have a high potential for triggering photosensitivity. A person is highly likely to display photosensitivity while using the device in a hospital ward. Therefore, special attention is required to avoid photosensitive seizures induced by barcode readers with red flashing lights.

Background The mental rotation task is well-known for the assessment of visuospatial function; however, it has not been used for screening of dementia patients. Objective The aim of this study was to create a simple screening test for patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD) by focusing on non-amnestic symptoms. Methods Age-matched healthy controls (age 75.3±6.8), patients with MCI (76.5±5.5), and AD (78.2±5.0) participated in this study. They carried out mental rotation tasks targeting geometric graphics or alphabetical characters with three rotating angles (0°, 90°, and 180°) and indicated the correct answer. Response accuracy and reaction time were recorded along with their eye movements using an eye tracker. To quantify their visual processing strategy, the run count ratio (RC ratio) was calculated by dividing the mean number of fixations in incorrect answers by that in correct answers. Results AD patients showed lower accuracy and longer reaction time than controls. They also showed a significantly greater number of fixation and smaller saccade amplitude than controls, while fixation duration did not differ significantly. The RC ratio was higher for AD, followed by MCI and control groups. By setting the cut-off value to 0.47 in the 180° rotating angle task, we could differentiate MCI patients from controls with a probability of 80.0%. Conclusions We established a new screening system for dementia patients by evaluating visuospatial function. The RC ratio during a mental rotation task is useful for discriminating MCI patients from controls.

Background and purpose: A group of international experts on intracranial artery dissection (IAD) recently reported a consensus statement and criteria about the diagnosis of IAD (Debette S, et al: Lancet Neurol 2015). But there are little data showing clinical features of IAD based on the new criteria. We aimed to elucidate clinical and radiological characteristics based on the criteria. Methods: Patients with suspected IAD were retrospectively enrolled using a prospective single-center stroke registry between 2011 and 2016. Baseline characteristics and radiological findings including conventional MRI sequences, MRA, 3D-T1 weighted TSE blood black (3DT1BB) sequence and digital subtraction angiography (DSA) were reviewed. Results: Of 147 patients with suspected IAD, 63 patients (15 women; mean age, 51±12 years) finally met the criteria of definite (n=47), probable (n=14) or possible (n=2) idiopathic IAD. Thirty-five (56 %) had a history of hypertension, 21 (33 %) had dyslipidemia, and 39 (62 %) had smoking habit. Ischemic stroke alone was found in 50 %, subarachnoid hemorrhage plus ischemic stroke in 6 %, TIA in 3 %, and head or neck pain alone in 41 % on admission. Vertebral artery was affected in 66 %, basilar artery in 2 %, posterior inferior cerebral artery in 5 %, anterior cerebral artery in 11 %, middle cerebral artery in 6 %, intracranial internal carotid artery in 2 % and multi-vessels in 8 %. Intimal flap, double lumen and aneurysmal dilatation were similarly observed between 3DT1BB and MRI/MRA/DSA. Intramural hematoma was more frequently detected in 3DT1BB sequence than conventional MRI/MRA (initial image, 53 % vs. 14 %, P < 0.001; follow-up image, 59 % vs. 22 %, P < 0.001). Follow-up image was essential to fulfill the criteria in 12 patients; rapid morphological change of aneurysmal dilation in 3, a newly detection of intramural hematoma in 3, double lumen in 2, pearl and string sign in 2, and aneurysmal dilation without change in morphology in 2 on follow-up images. Modified Rankin Scale score of ≤ 1 at 90 days was observed in 54 patients (86 %). Conclusions: Intracranial vertebral artery was most frequently affected. 3DT1BB sequence was apparently useful in detecting intraluminal hematoma in the recently proposed diagnostic criteria of idiopathic IAD.

This open access book presents the roles and mechanisms of signal transduction triggered by nicotinic acetylcholine receptors (nAChRs) stimulation in neuroprotection against toxic effects of risk factors of neurodegenerative diseases. Accumulating evidence suggests that nAChRs in the CNS play important roles not only in excitatory neurotransmission but also in neuronal survival and related functions. Neuroprotection mediated by nAChRs in neurodegenerative diseases such as Alzheimer's disease is the major topic of this book. In response to rapidly evolving areas in clinical and laboratory neuropharmacology and neurochemistry, this volume provides in-depth coverage of neuroprotection in basic research and future developments in the clinical application of effective neuroprotective strategies in neurodegenerative diseases. This work appeals to both basic and clinical researchers in several fields, such as neuroscience, neurology, and pharmacology.

Both of the two most common neurodegenerative disorders, namely Alzheimer’s disease (AD) and Parkinson’s disease (PD), have multiple lines of evidence, from molecular and cellular to epidemiological, that nicotinic transmission is implicated in those pathogenesis. This review presents evidences of nicotinic acetylcholine receptor (nAChR)-mediated protection against neurotoxicity induced by β amyloid (Aβ), glutamate, rotenone, and 6-hydroxydopamine (6-OHDA) and the signal transduction involved in this mechanism. Our studies clarified that survival signal transduction, α7 nAChR-Src family-PI3K-AKT pathway and subsequent upregulation of Bcl-2 and Bcl-x, would lead to neuroprotection. Recently analyzing the properties of galantamine, we clarified the neuroprotective pathway, which is mediated by enhancement of microglial α7 nAChR resulting in upregulation of Aβ phagocytosis. Galantamine sensitizes microglial α7 nAChRs to choline and induce Ca2+ influx into microglia. The Ca2+-induced intracellular signaling cascades may then stimulate Aβ phagocytosis through the actin reorganization. This discovery would facilitate further investigation of possible nAChRs enhancing drugs targeting not only neuronal but also microglial nAChRs.

Alzheimer disease (AD) is a neurodegenerative disease clinically characterized by progressive cognitive dysfunction. Deposition of amyloid-β (Aβ) peptides is the most important pathophysiological hallmark of AD. Oxidative stress induced by reactive oxygen species is prominent in AD, and several reports suggest the relationship between a change in redox status and AD pathology containing progressive Aβ deposition, the activation of glial cells, and mitochondrial dysfunction. Therefore, we performed immunohistochemical analysis using a transgenic mouse model of AD (APdE9) and evaluated the activity of superoxide dismutase in brain tissue homogenates of APdE9 mice in vitro. Together with those analyses, in vivo changes in redox status with age in both wild-type (WT) and APdE9 mouse brains were measured noninvasively by three-dimensional electron paramagnetic resonance (EPR) imaging using nitroxide (3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-yloxy) as a redox-sensitive probe. Both methods found similar changes in redox status with age, and in particular a significant change in redox status in the hippocampus was observed noninvasively by EPR imaging between APdE9 mice and age-matched WT mice from 9 to 18 months of age. EPR imaging clearly visualized the accelerated change in redox status of APdE9 mouse brain compared with WT. The evaluation of the redox status in the brain of AD model rodents by EPR imaging should be useful for diagnostic study of AD.

The diagnosis of idiopathic normal pressure hydrocephalus (iNPH) is sometimes complicated by concomitant Alzheimer's disease (AD) pathology. The purpose of the present study is to identify an iNPH-specific cerebrospinal fluid (CSF) biomarker dynamics and to assess its ability to differentiate iNPH from AD. Total tau (t-tau), tau phosphorylated at threonine 181 (p-tau), amyloid-β (Aβ) 42 and 40, and leucine-rich α-2-glycoprotein (LRG) were measured in 93 consecutive CSF samples consisting of 55 iNPH (46 tap test responders), 20 AD, 11 corticobasal syndrome, and 7 spinocerebeller disease. Levels of t-tau and p-tau were significantly decreased in iNPH patients especially in tap test responders compared to AD. Correlation was observed between Mini-Mental State Examination scores and Aβ42 in AD (R = 0.44) and mildly in iNPH (R = 0.28). Although Aβ42/40 ratio showed no significant difference between iNPH and AD (p = 0.08), the levels of Aβ40 and Aβ42 correlated positively with each other in iNPH (R = 0.73) but much less in AD (R = 0.26), suggesting that they have discrete amyloid clearance and pathology. LRG levels did not differ between the two. Thus, our study shows that although CSF biomarkers of iNPH patients can be affected by concomitant tau and/or amyloid pathology, CSF t-tau and p-tau are highly useful for differentiation of iNPH and AD.

We previously reported that activated microglia are involved in amyloid-β (Aβ) clearance and that stimulation of α7 nicotinic acetylcholine receptors (nAChR) in microglia enhances Aβ clearance. Nevertheless, how microglia and α7 nAChR in microglia are affected in Alzheimer's disease (AD) remains unknown. The present study aimed to collect fundamental data for considering whether microglia are potential targets for AD treatment and the appropriate timing of therapeutic intervention, by evaluating the temporal changes of Aβ, microglia, neurons, presynapses, and α7 nAChR by immunohistochemical studies in mouse models of AD. In an Aβ-injected AD mouse model, we observed early accumulation of CD68-positive microglia at Aβ deposition sites and gradual reduction of Aβ. Microglia were closely associated with Aβ deposits, and were confirmed to participate in clearing Aβ. In a transgenic mouse model of AD, we observed an increase in Aβ deposition from 6 months of age, followed by a gradual increase in microglial accumulation at Aβ deposit sites. Activated microglia in APdE9 mice showed two-step transition: a CD68-negative activated form at 6-9 months and a CD68-positive form from 12 months of age. In addition, α7 nAChR in microglia increased markedly at 6 months of age when activated microglia appeared for the first time, and decreased gradually coinciding with the increase of Aβ deposition. These findings suggest that early microglial activation is associated with α7 nAChR upregulation in microglia in APdE9 mice. These novel findings are important for the development of new therapeutic strategy for AD.

An 85-year-old woman was first admitted to our hospital because of right ptosis and diplopia. Examinations showed right oculomotor paralysis and reduced vision in the right eye. Serological and neuroradiological examinations failed to reveal the etiology. Oral prednisolone was started for a presumptive diagnosis of idiopathic oculomotor nerve palsy, which resulted in little improvement. Approximately ten months after the first admission, left ptosis appeared and she was re-admitted to our hospital. One day after admission, external ophthalmoplegia and conjunctival injection on the left side appeared. MRI revealed abnormal flow void in the right cavernous sinus. Based on cerebral angiographic findings, dural arteriovenous fistula of the right cavernous sinus was diagnosed. Symptoms on the left side were considered to result from increased perfusion pressure due to venous drainage via the intercavernous sinus to the contralateral cavernous sinus. After transvenous embolization, symptoms and signs improved gradually. In a case of external ophthalmoplegia with unknown etiology, detailed neuroradiologyical examinations such as cerebral angiogram are advisable.

To explore a novel therapy against Parkinson's disease (PD), we evaluated the therapeutic effects of human bone marrow-derived mesenchymal stem cells (hBM-MSCs), pluripotent stromal cells with secretory potential of various neurotrophic and anti-inflammatory factors, in a hemi-parkinsonian rat model. The unilateral intrastriatal 6-hydroxydopamine (6-OHDA)-lesioned rats were injected hBM-MSCs (1.0 × 107 cells) or PBS intravenously 16 days after lesioning. Administration of hBM-MSCs inhibited methamphetamine-stimulated rotational behavior at 7, 14, 21 and 28 days after transplantation. Immunohistochemical analysis also showed that number of TH-positive neurons in the substantia nigra pars compacta was significantly preserved in hBM-MSCs-transplanted rats compared to sham-operated rats, whereas the immunoreactivity of ionized calcium binding adaptor molecule 1 was markedly inhibited. In this study, we demonstrated the therapeutic effects of intravenous hBM-MSCs administration in parkinsonian model rats presenting distinct parkinsonian phenotype at 16 days after 6-OHDA lesioning. The favorable findings raise the possibility that hBM-MSCs could be a novel therapeutic option to promote survival of dopaminergic neurons in PD.

Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is characterized by impaired mitochondrial β-oxidation of fatty acids. The fatty acid oxidation plays a significant role in energy production especially in skeletal muscle. VLCAD is one of four acyl-CoA dehydrogenases with different-chain length specificity and catalyzes the initial step in mitochondrial β-oxidation of fatty acids. While the clinical phenotypes in neonates and infants are described as severe, adolescent-onset or adult-onset VLCAD deficiency has a more benign course with only skeletal muscle involvement. These myopathic phenotypes are characterized by episodic muscle weakness and rhabdomyolysis triggered by fasting and strenuous exercise. We report a male teenager who manifested repeated episodes of rhabdomyolysis immediately after exertional exercise. Rhabdomyolysis was diagnosed based on the marked elevation of serum creatine kinase and myoglobinuria. Acylcarnitine analysis by tandem mass spectrometry (MS/MS) revealed elevation of serum tetradecenoylcarnitine (C14:1-AC), which represents an abnormal acylcarnitine profile associated with the mitochondrial β-oxidation defect. High performance liquid chromatographic analysis showed decreased production of 2-hexadecenoyl-CoA (C16:1) from palmitoyl-CoA (C16:0), indicating the defect of VLCAD activity. Direct sequencing of the acyl-CoA dehydrogenase, very long-chain gene (ACADVL) that codes VLCAD revealed a heterozygous mutation (c.1242G>C) in exon 12 (E414D), which is a novel mutation in myopathic-type VLCAD deficiency. Because VLCAD functions as a homodimer, we assume that this heterozygous mutation may exhibit dominant-negative effect. This patient remains asymptomatic thereafter by avoiding exertional exercise. The findings of reduction of enzyme activity and clinical features associated with this novel missense mutation of VLCAD are discussed.

We report the case of a 67-year-old woman with non-convulsive status epilepticus (NCSE) due to hyponatremia. She had a history of psychogenic polydipsia but not epilepsy. She was admitted to our hospital with dysbulia. On admission, she was confused and disoriented (Glasgow Coma Scale: 6, E1V1M4). Magnetic resonance imaging of the brain showed no abnormalities. Laboratory test showed hyponatremia (Na

Objective The ice-pack test is a convenient diagnostic testing procedure for myasthenia gravis (MG). We investigated the underlying mechanism of the ice-pack test performed on bilateral masseters. Methods We performed trigeminal repetitive nerve stimulation (RNS), excitation-contraction (E-C) coupling assessment (Imai’s method) and bite force measurement before and after cooling of the masseters in MG patients and normal controls. After placing the ice-pack on the masseters for 3 min, serial recordings of the three tests were performed at various time intervals during 10 min after cooling. Results The bite force increased significantly after cooling in ice-pack-positive MG patients. The acceleration and acceleration ratio (acceleration at a given time to baseline acceleration) of jaw movement increased significantly after cooling of the masseters in ice-pack-positive MG patients compared to ice-pack-negative patients and normal controls. The prolonged effect of cooling continued until the end of recording even though decremental response to RNS had returned to baseline value. Conclusions Cooling of myasthenic muscle may induce two effects. One is relatively short effect on electrical synaptic transmission at the endplate, and another is prolonged effect on E-C coupling in the muscle. Significance The ice-pack test induces a prolonged effect of ameliorating impaired E-C coupling in MG.

We previously demonstrated that stimulation of nicotinic acetylcholine receptors (nAChRs) increases amyloid-β (Aβ) phagocytosis in rat microglia and is closely associated with the decrease of brain Aβ and amelioration of memory dysfunction in a transgenic mouse model of Alzheimer's disease (AD). Here, we examined the subtypes of nAChRs involved in these beneficial effects. In primary cultures of rat microglia, the α7 nAChR selective agonist 3-[(2,4-dimethoxy)benzylidene]-anabaseine dihydrochloride (DMXBA) promoted Aβ and fluorescent latex bead phagocytosis, whereas selective α7 nAChR antagonists suppressed the enhanced Aβ phagocytosis. In a transgenic mouse model of AD, administration of DMXBA attenuated brain Aβ burden and memory dysfunction. Moreover, DMXBA suppressed γ-secretase activity in solubilized fractions of human neuroblastoma cells and transgenic mouse brain. These results suggested that selective activation of α7 nAChRs promoted microglial Aβ phagocytosis and suppressed neuronal γ-secretase activity to contribute to the attenuation of the brain Aβ burden and cognitive impairment. Thus, we propose neuronal and microglial α7 nAChRs as new therapeutic targets in the treatment of AD.

A 30-year-old woman was admitted to our hospital because of intractable orbital pain and ptosis on the left side. On admission, she had left oculomotor, ophthalmic and maxillary nerves palsy. MRI revealed a contrast enhanced lesion of the left oculomotor and trigeminal nerves through the covernous sinus and orbita. We diagnosed her condition as Tolosa-Hunt syndrome. The orbital pain was resolved within 48-hours by the pulse therapy with intra-venous methylpredonisolone. The cranial nerve palsy was gradually improved, but never reached complete remission. The left oculomotor and trigeminal nerves also remained enhanced on MRI until 200 days from the onset. Although there have been few reports to demonstrate the contrast enhancement of cranial nerves in Tolosa-Hunt syndrome, these MRI findings may be a specific indicator of the pathological process.

Involvement of cranial nerves caused by cranial base lesions manifests diverse symptoms according to the localization of lesions. These localization-related symptoms are classified into syndromes such as orbital apex syndrome, cavernous sinus syndrome, and jugular foramen syndrome. Since the lesions may have various etiologies including infection, inflammation and tumor, etiological diagnosis should be performed simultaneously if possible. However, previous reports have described poor and/or fatal outcome following inappropriate treatment mainly due to difficulties in making a definitive pathological diagnosis. Nineteen patients with multiple cranial nerve involvement caused by skull base lesions were enrolled over the past 12 years. The patients were divided into an "infectious" group (n=11) and a "noninfectious" group (n=8) based on the final diagnosis. Chi-square analysis was conducted to examine the sensitivity and specificity of various factors including patient characteristics, clinical course and treatment response in infectious and noninfectious groups. Consequently, we identified some patients with good outcome irrespective of infectious or noninfectious etiology, even though a pathological diagnosis was not reached before the initial treatment. These patients with good outcome consistently received antifungal therapy in the early stage if infectious etiologies were suspected. We recommend conducting diagnostic therapy with antifungal drugs in patients with skull base lesions of unknown origin although infection cannot be excluded, when a pathological diagnosis is difficult due to various patient conditions.

A 79 year-old female was admitted to our hospital because of high serum creatine kinase level together with proximal muscle weakness and pain on grasping. MRI revealed inflammatory changes in femoral muscles on both sides. Muscle biopsy showed size irregularity of muscle cells, and necrosis and regeneration of fibers. Study of antibodies was also consistent with the diagnostic criteria of anti-signal recognition particle (anti-SRP) antibody-positive myopathy. On admission, the patient required pericardiocentesis for the management of exudative pericarditis. Accompanying the aggravation of myositis, negative T wave in precordial leads on ECG, ventricular extrasystoles and non-sustained ventricular tachycardia were observed. These abnormalities were resolved with the improvement of myositis by immunosuppressive treatment. These observations suggest that the myopericarditis was associated with anti-SRP antibody-positive myopathy.

Previously, DJ-1 modulator UCP0054278/comp-B was identified by virtual screening, where comp-B interacts with DJ-1 to produce antioxidant and neuroprotective responses in Parkinson's disease models. However, the effect of comp-B in an in vivo Alzheimer's disease (AD) model is yet undetermined. Thus, we examined the effect of comp-B on spatial learning, memory, and amyloid-β (Aβ) clearance in a transgenic mouse model of AD. We found that comp-B resolved the cognitive deficits, reduced insoluble Aβ42 levels, and prevented the degeneration of synaptic functions, thereby suggesting that comp-B may become a major compound for AD treatment.

Background Higher latitude and human leukocyte antigen (HLA)-DRB1*04:05 increase susceptibility to multiple sclerosis (MS) in the Japanese population, but their effects on disease severity are unknown. We aimed to clarify the effects of latitude and the HLA-DRB1 and HLA-DPB1 genes on disease severity in Japanese patients with MS. Methods We enrolled 247 MS patients and 159 healthy controls (HCs) from the northernmost main island of Japan, Hokkaido Island (42–45° north), and 187 MS patients and 235 HCs from the southern half (33–35° north) of the Japanese archipelago (33–45° north). We genotyped HLA-DRB1 and HLA-DPB1 alleles, compared demographic features, and analyzed factors contributing to differences in clinical and laboratory findings between MS patients from southern and northern Japan. The Multiple Sclerosis Severity Score (MSSS), which adjusts the Kurtzke’s Expanded Disability Status Scale score according to disease duration, was used to estimate disease severity. Results The HLA-DRB1*04:05 and DRB1*15:01 alleles conferred susceptibility to MS in our Japanese population (pcorr = 0.0004 and pcorr = 0.0019, respectively). Southern patients had higher MSSS scores than northern patients (p = 0.003). Northern patients had higher frequencies of brain lesions meeting the Barkhof criteria (Barkhof brain lesions) and cerebrospinal fluid (CSF) IgG abnormalities than southern patients (p = 0.0012 and p

Background Malnutrition induced by swallowing difficulties (SD) impairs the quality of life and gives rise to SD-related costs in Parkinson’s disease (PD) patients. With results of a swallowing difficulty questionnaire and data of resources specifically obtained such as SD-related costs, caregivers, and dietary therapies, this study is to suggest statistically supported ideas for improvements in arrangements for how participants cope with SD and maintain general well-being. Methods We interviewed 237 PD patients. The SD-related costs involved those incurred by the provision of dietary modifications, care oriented foods, alternatives, and supplements. Dietary therapies included rice porridge and commercially available care foods. The relationships between BMI (body mass index) and the severity of SD assumed in this paper as indicators for general well-being and as resources for coping with SD for PD patients were statistically analyzed. Results A lower BMI was found in participants eating porridge consistency rice (p = 0.003) and eating porridge rice is significantly related to the severity of SD (p

Parkinson’s disease (PD) is a progressive, age-related, neurodegenerative disorder and oxidative stress is an important mediator in its pathogenesis. DJ-1, the product of the causative gene of a familial form of PD, plays a significant role in anti-oxidative defence to protect cells from oxidative stress. DJ-1 undergoes preferential oxidation at the cysteine residue at position 106 (Cys-106) under oxidative stress. Here, using specific antibodies against Cys-106-oxidized DJ-1 (oxDJ-1), it was found that the levels of oxDJ-1 in the erythrocytes of unmedicated PD patients (n = 88) were higher than in those of medicated PD patients (n = 62) and healthy control subjects (n = 33). Elevated oxDJ-1 levels were also observed in a non-human primate PD model. Biochemical analysis of oxDJ-1 in erythrocyte lysates showed that oxDJ-1 formed dimer and polymer forms and that the latter interacts with 20S proteasome. These results clearly indicate a biochemical alteration in the blood of PD patients, which could be utilized as an early diagnosis marker for PD.

We investigated the effect of load against self-paced movement on cortical involvement for motor execution. Ten right-handed healthy volunteers were requested to perform brisk extension of the right index finger at self-paced intervals exceeding 10s for three load conditions: 0g, 50g and 100g. Movement-related magnetic fields were recorded using an MEG system. The signals were band-pass-filtered through 18-23Hz and rectified before averaging with respect to EMG onset. We analyzed the time course and %change of peak amplitude with reference to the baseline amplitude in event-related desynchronization (ERD) or synchronization (ERS) in each hemisphere. Maximum response was observed around the left somatomotor area for all conditions. ERD did not show any significant difference before the movement onset among the three load conditions. For %change, ERS in the post-movement period was significantly larger for the 100g load condition than for the 0g load condition, and that was significantly greater over the left than over the right hemisphere. These findings indicate that the load has little effect on pre-movement desynchronization, whereas it affects the post-movement synchronization on background rhythms.

Objectives Tacrolimus (FK506) is a macrolide T-cell immunomodulator used to treat myasthenia gravis (MG). Besides immunosuppression, tacrolimus has been reported to have the potential to increase muscle strength by enhancing ryanodine receptor (RyR) function. However, few attempts have been made to demonstrate the early effect of tacrolimus as an RyR enhancer in clinical investigation. Methods In 20 MG patients, masseteric compound muscle action potential (CMAP) and mandibular movement-related potentials (MRPs) were recorded simultaneously after stimulating the trigeminal motor nerve with a needle electrode. The excitation–contraction (E–C) coupling time (ECCT) was calculated by the latency difference between CMAP and MRP. Bite force was measured using a pressure-sensitive sheet. Serial assessments of % decrement in masseteric repetitive nerve stimulation (RNS), ECCT and bite force were performed before and within 4weeks of tacrolimus (3mgday −1 ) treatment. The median (mean, range) interval of assessment was 2 (2.4, 1–4) weeks. We also measured serum antibodies against RyR, acetylcholine receptor and muscle-specific receptor tyrosine kinase. Results Bite force increased after tacrolimus treatment accompanying clinical improvement assessed by Myasthenia Gravis Foundation of America classification, but the bite force difference did not reach statistical significance. Wilcoxon matched-pairs signed-ranks test detected a significant ECCT shortening in 12 patients assessed after 1–2weeks of tacrolimus treatment as well as in eight patients assessed after 3–4weeks. In contrast, masseteric CMAP and % decrement showed no significant changes after short-term tacrolimus treatment. Conclusions Tacrolimus induces ECCT shortening accompanying clinical improvement despite no improvement in % decrement within 2weeks. Significance This early effect of tacrolimus may imply a pharmacological enhancement of RyR function to improve E–C coupling in MG.