Quadripulse stimulation (QPS).

Quadripulse stimulation (QPS) is a newly developed stimulation method to induce neural plasticity in humans. One stimulation burst consisting of four monophasic pulses is given every 5 s for 30 min. A total of 360 bursts (1440 pulses) are given in one session. Short-interval QPS potentiates the target cortical excitability and long-interval QPS depresses it. QPS at an inter-pulse interval of 5 ms (QPS5) induces long-term potentiation (LTP)-like effects most efficiently and QPS50 induces long-term depression (LTD)-like effects most effectively in the primary motor cortex. In this mini-review, we briefly introduce QPS: (i) principle and cortical plasticity (stimulators and protocols, synaptic plasticity, underlying mechanisms, meta-plasticity, axonal plasticity, and drug effects), (ii) robust and strong neural plasticity induction (variability, influence of phasic muscle contraction, independency of BDNF polymorphism, sensory cortical plasticity, neural plasticity in the contralateral hemisphere, on-line effects on the brain networks, studies of normal brain physiology, and visuomotor sequence learning), (iii) therapeutic applications to neurological and psychiatric disorders (Parkinson's disease, epilepsy, cerebrovascular disease, and major depression), (iv) safety, and (v) future issues. Based on this evidence, we propose that QPS is currently the most powerful and reliable non-invasive brain stimulation method to induce neural plasticity in humans.

Asymmetric Bálint's syndrome with multimodal agnosia, bilateral agraphesthesia, and ineffective kinesthetic reading due to subcortical hemorrhage in the left parieto-occipito-temporal area.

We report a patient with asymmetric Bálint's syndrome (predominantly right-sided oculomotor apraxia and simultanagnosia and optic ataxia for the right hemispace), and multimodal agnosia (apperceptive visual agnosia and bilateral associative tactile agnosia) with accompanying right hemianopia, bilateral agraphesthesia, hemispatial neglect, global alexia with unavailable kinesthetic reading, and lexical agraphia for kanji (Japanese morphograms), after hemorrhage in the left parieto-occipito-temporal area. The coexistence of tactile agnosia, bilateral agraphesthesia, and ineffective kinesthetic reading suggests that tactile-kinesthetic information can be interrupted because of damage to the fiber connection from the parietal lobe to the occipito-temporal area, leading to these tactually related cognitive impairments.

A patient with McLeod syndrome showing involvement of the central sensorimotor tracts for the legs.

BACKGROUND: McLeod syndrome is a rare X-linked recessive acanthocytosis associated with neurological manifestations including progressive chorea, cognitive impairment, psychiatric disturbances, seizures, and sensorimotor axonal polyneuropathy. However, no studies have investigated the functioning of central sensorimotor tracts in patients with McLeod syndrome. CASE PRESENTATION: A 66-year-old man had experienced slowly progressive chorea and gait disturbance due to lower limb muscle weakness since his early fifties. Blood examinations showed erythrocyte acanthocytosis and the reduction of Kell antigens in red blood cells. Brain magnetic resonance imaging showed atrophy of the bilateral caudate nuclei and putamen. The diagnosis of McLeod syndrome was confirmed by the presence of a mutation of the XK gene on the X chromosome. Somatosensory-evoked potential and transcranial magnetic stimulation studies demonstrated that the central sensory and motor conduction times were abnormally prolonged for the lower extremity but normal for the upper extremity. CONCLUSIONS: This is the first report of the involvement of the central sensorimotor tracts for the legs in a patient with McLeod syndrome. The clinical neurophysiological technique revealed the central sensorimotor tracts involvements clinically masked by neuropathy.

Lenalidomide-Induced Ischemic Cerebrovascular Disease in Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal Gammopathy, and Skin Changes Syndrome.

We describe the case of a 34-year-old woman with polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome. She developed transient ischemic attack after the introduction of lenalidomide plus dexamethasone (Rd) therapy despite no vascular risk factors. Magnetic resonance and computed tomography angiographies showed bilateral internal carotid artery stenosis. Rd therapy was suspended because of its thromboembolic risk. She had been neurologically stable during the suspension of Rd therapy. After Rd therapy was restarted, however, she repeated ischemic cerebrovascular disease. Rd therapy was switched to carfilzomib plus dexamethasone therapy. Thereafter, she had been neurologically stable. Multivessel stenosis is infrequently seen in POEMS syndrome. Therefore, magnetic resonance angiography should be performed before introducing Rd therapy in POEMS syndrome.

Syncephalastrum racemosum amine oxidase with high catalytic efficiency toward ethanolamine and its application in ethanolamine determination.

Our screening study yielded a copper amine oxidase (SrAOX) from Syncephalastrum racemosum, which showed much higher affinity and catalytic efficiency toward ethanolamine (EA) than any other amine oxidase (AOX). Following purification of the enzyme to electrophoretic homogeneity from a cell-free extract, the maximum activity toward EA was detected at pH 7.2-7.5 and 45 °C. The SrAOX complementary DNA (cDNA) was composed of a 2052-bp open reading frame encoding a 683-amino acid protein with a molecular mass of 77,162 Da. The enzyme functions as a homodimer. The deduced amino acid sequence of SrAOX showed 55.3 % identity to Rhizopus delemar AOX and contains two consensus sequences of Cu-AOX, NYDY, and HHQH, suggesting SrAOX is a type 1 Cu-AOX (i.e., a topaquinone enzyme). Structural homology modeling showed that residues (112)ML(113), (141)FADTWG(146) M158, and N318 are unique, and T144 possibly characterizes the substrate specificity of SrAOX. The recombinant enzyme (rSrAOX) was produced using Escherichia coli. Steady-state kinetic analysis of rSrAOX activity toward EA (pH 7.5 and 45 °C) gave K m and k cat values of 0.848 ± 0.009 mM and 9.11 ± 0.13 s(-1), respectively. The standard curves were linear between 0.1 and 2 mM EA, and 10 µg mL(-1)-2.5 mg mL(-1) (15 µM-3.6 mM) phosphatidylethanolamine using Streptomyces chromofuscus phospholipase D, respectively, was sufficiently sensitive for clinical use.

Hydrolysis of plasmalogen by phospholipase A1 from Streptomyces albidoflavus for early detection of dementia and arteriosclerosis.

OBJECTIVES: To obtain an ethanolamine plasmalogen (PlsEtn)-hydrolyzing enzyme and to develop an assay that would help determine PlsEtn concentrations in human serum as an indicator of Alzheimer-type dementia and of arteriosclerosis. RESULTS: Phospholipase A1s, SaPLA1 and SvPLA1 from, respectively, Streptomyces albidoflavus NA297 and S. avermitilis JCM5070-but not phospholipase B from Streptomyces sp. NA684, PLA2-Nagase from S. avermitilis, PLA2IIL from S. violaceoruber nor LIPOMOD 699L (porcine phospholipase)-hydrolyzed choline plasmalogen (PlsCho) and PlsEtn (PlsCho preferred over PlsEtn). Using a combination of SaPLA1, lysoplasmalogen-specific phospholipase D (LyPls-PLD), with amine oxidase, an end-point assay was developed for measuring serum PlsEtn concentration. The standard curve, generated using various amounts of PlsEtn in this assay, was linear between 0 and 0.2 mM. PlsEtn concentrations in forty-seven serum samples, determined independently by this enzyme-based assay and (125)I-HPLC method, exhibited a linear relationship, indicating that the assay is suitable for fast and accurate measurement of serum PlsEtn concentration. CONCLUSIONS: An assay, developed using SaPLA1, LyPls-PLD, and AOX, selectively measured PlsEtn levels in blood samples. This assay could be a useful diagnostic tool for early stage detection of diseases such as Alzheimer-type dementia and arteriosclerosis.

Visual scanning area is abnormally enlarged in hereditary pure cerebellar ataxia.

The aim of paper was to investigate abnormalities in visual scanning using an eye-tracking device with patients with spinocerebellar ataxia type 6 (SCA6) and SCA31, pure cerebellar types of spinocerebellar degeneration. Nineteen SCA patients (12 patients with SCA6 and 7 patients with SCA31) and 19 normal subjects in total participated in the study. While the subjects viewed images of varying complexity for later recall, we compared the visual scanning parameters between SCA patients and normal subjects. SCA patients had lower image recall scores. The scanned area in SCA patients was consistently larger than that in normal subjects. The amplitude of saccades was slightly larger in SCA patients than that in normal subjects, although it did not statistically differ between the two groups and correlated significantly with the scanned area in most images in SCA patients. The instability ratio of fixation, reflecting gaze-evoked nystagmus and downbeat nystagmus, was higher in SCA patients than that in normal subjects. Since SCA patients showed low scores despite wide visual scanning, the scanned area is considered to be abnormally enlarged. The larger scanned area in SCA patients was supposed mainly to result from the slightly larger saccade amplitude. Additionally, SCA patients showed prominent fixation disturbances probably due to gaze-evoked nystagmus and downbeat nystagmus. Consequently, SCA patients suffer from recognizing various objects in daily life, probably due to the impaired saccade control and impaired fixation.

Central and Peripheral Motor Conduction Studies by Single-Pulse Magnetic Stimulation.

Single-pulse magnetic stimulation is the simplest type of transcranial magnetic stimulation (TMS). Muscle action potentials induced by applying TMS over the primary motor cortex are recorded with surface electromyography electrodes, and they are called motor-evoked potentials (MEPs). The amplitude and latency of MEPs are used for various analyses in clinical practice and research. The most commonly used parameter is the central motor conduction time (CMCT), which is measured using motor cortical and spinal nerve stimulation. In addition, stimulation at the foramen magnum or the conus medullaris can be combined with conventional CMCT measurements to evaluate various conduction parameters in the corticospinal tract more precisely, including the cortical-brainstem conduction time, brainstem-root conduction time, cortical-conus motor conduction time, and cauda equina conduction time. The cortical silent period is also a useful parameter for evaluating cortical excitability. Single-pulse magnetic stimulation is further used to analyze not only the central nervous system but also the peripheral nervous system, such as for detecting lesions in the proximal parts of peripheral nerves. In this review article we introduce four types of single-pulse magnetic stimulation-of the motor cortex, spinal nerve, foramen magnum, and conus medullaris-that are useful for the diagnosis, elucidation of pathophysiology, and evaluation of clinical conditions and therapeutic effects. Single-pulse magnetic stimulation is a clinically useful technique that all neurologists should learn.

Successful Childbirth During Satralizumab Treatment in Neuromyelitis Optica Spectrum Disorder.

A 40-year-old woman with neuromyelitis optica spectrum disorder (NMOSD) and anti-aquaporin 4 antibodies suffered three NMOSD episodes between 35 and 37 years of age. Despite treatment with prednisolone and azathioprine, her condition repeatedly relapsed. We introduced satralizumab, targeting interleukin-6 receptors, which stabilized her condition. At the age of 38, she became pregnant and delivered a healthy baby at 38 weeks. Post delivery, both mother and child stayed healthy with no NMOSD relapses. This case illustrates the efficacy and safety of satralizumab in managing NMOSD, especially for women in their reproductive years who are planning pregnancy.

Ischemic Stroke During Daprodustat Therapy for Renal Anemia: A Report of Three Cases.

Hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitors are increasingly used to treat renal anemia. Ischemic stroke is a rare severe adverse event of HIF-PH inhibitor therapy, and its clinical characteristics have not been described to date. We report three cases of ischemic stroke during treatment with daprodustat, a HIF-PH inhibitor, for anemia associated with non-dialysis-dependent chronic kidney disease (CKD). In two patients, the hemoglobin level exceeded the target hemoglobin level of 13 g/dL for renal anemia. Two patients developed ischemic stroke within two months after the daprodustat administration. None of the three patients experienced a recurrence of ischemic stroke after daprodustat discontinuation. Daprodustat therapy is a risk factor for ischemic stroke, particularly during excessive elevation of hemoglobin levels or the early phases of treatment. Daprodustat should be discontinued to mitigate the risk of ischemic stroke recurrence.

Cortical hemoglobin concentration changes underneath the coil after single-pulse transcranial magnetic stimulation: a near-infrared spectroscopy study.

Using near-infrared spectroscopy (NIRS) and multichannel probes, we studied hemoglobin (Hb) concentration changes when single-pulse transcranial magnetic stimulation (TMS) was applied over the left hemisphere primary motor cortex (M1). Seventeen measurement probes were centered over left M1. Subjects were studied in both active and relaxed conditions, with TMS intensity set at 100%, 120%, and 140% of the active motor threshold. The magnetic coils were placed so as to induce anteromedially directed currents in the brain. Hb concentration changes were more prominent at channels over M1 and posterior to it. Importantly, Hb concentration changes at M1 after TMS differed depending on whether the target muscle was in an active or relaxed condition. In the relaxed condition, Hb concentration increased up to 3-6 s after TMS, peaking at ∼6 s, and returned to the baseline. In the active condition, a smaller increase in Hb concentrations continued up to 3-6 s after TMS (early activation), followed by a decrease in Hb concentration from 9 to 12 s after TMS (delayed deactivation). Hb concentration changes in the active condition at higher stimulus intensities were more pronounced at locations posterior to M1 than at M1. We conclude that early activation occurs when M1 is activated transsynaptically. The relatively late deactivation may result from the prolonged inhibition of the cerebral cortex after activation. The posterior-dominant activation at higher intensities in the active condition may result from an additional activation of the sensory cortex due to afferent inputs from muscle contraction evoked by the TMS.

Increased gene dosage of myelin protein zero causes Charcot-Marie-Tooth disease.

OBJECTIVE: On the basis of the hypothesis that copy number mutations of the genes encoding myelin compact proteins are responsible for myelin disorders in humans, we have explored the possibility of copy number mutations in patients with Charcot-Marie-Tooth disease (CMT) whose responsible genes remain undefined. METHODS: A family with 6 affected members in 3 consecutive generations, presenting with motor and sensory demyelinating polyneuropathy, was investigated. Characteristic clinical features in this pedigree include Adie pupils and substantial intrafamilial variability in the age at onset, electrophysiological findings, and clinical severity. Nucleotide sequence analyses of PMP22, MPZ, or GJB1 and gene dosage study of PMP22 did not reveal causative mutations. Hence, we applied a custom-designed array for comparative genomic hybridization (CGH) analysis to conduct a comprehensive screening of copy number mutations involving any of the known causative genes for CMT other than PMP22. RESULTS: The array CGH analyses revealed increased gene dosage involving the whole MPZ, and the flanking genes of SDHC and C1orf192. The gene dosage is estimated to be 5 copies. This mutation showed complete cosegregation with the disease phenotype in this pedigree. INTERPRETATION: The increased gene dosage of MPZ and increased expression level of MPZ mRNA emphasize the important role of the dosage of the MPZ protein in the functional integrity of peripheral nerve myelin in humans, and provide a new insight into the pathogenic mechanisms underlying CMT.

Innate versus learned odour processing in the mouse olfactory bulb.

The mammalian olfactory system mediates various responses, including aversive behaviours to spoiled foods and fear responses to predator odours. In the olfactory bulb, each glomerulus represents a single species of odorant receptor. Because a single odorant can interact with several different receptor species, the odour information received in the olfactory epithelium is converted to a topographical map of multiple glomeruli activated in distinct areas in the olfactory bulb. To study how the odour map is interpreted in the brain, we generated mutant mice in which olfactory sensory neurons in a specific area of the olfactory epithelium are ablated by targeted expression of the diphtheria toxin gene. Here we show that, in dorsal-zone-depleted mice, the dorsal domain of the olfactory bulb was devoid of glomerular structures, although second-order neurons were present in the vacant areas. The mutant mice lacked innate responses to aversive odorants, even though they were capable of detecting them and could be conditioned for aversion with the remaining glomeruli. These results indicate that, in mice, aversive information is received in the olfactory bulb by separate sets of glomeruli, those dedicated for innate and those for learned responses.

Low temperature phase properties of water confined in mesoporous silica MCM-41: thermodynamic and neutron scattering study.

The phase properties of water confined in mesoporous silica MCM-41 were investigated over a temperature range of 100-298 K as a function of pore size by specific heat capacity and inelastic neutron scattering (INS) measurements. The water content of the samples was carefully controlled to ensure the capillary filled state and no overloading of water. The values of heat capacity of the pore water are higher than those of bulk ice and liquid water over the whole temperature range measured. The contribution of water in the inner part of pores (abbreviated as the internal water) was elucidated by using the heat capacity data of monolayer water measured. The entropy of the internal water was then estimated from integration of the heat capacity of the internal water. The entropy values of the internal water increase by confinement in the pores of MCM-41 in both liquid and frozen regions, indicating an increase in the deformation of the structure and∕or a change in the dynamics in both regions. The INS spectra show the density of states for the librational motion of water frozen at 50 K, suggesting that the confined water is similar to amorphous ice rather than to crystalline ice. When the sample is warmed to melt, the band edge of the librational motion for water frozen in large pores (diameter of 3.6 nm) shifts to a lower energy side, indicating the weakening of intermolecular hydrogen bonds. For water in small pores (2.1 nm), on the contrary, the librational band shifts slightly to a higher energy side, suggesting the low density liquid to high density liquid transition (L-L transition) at 225-250 K. A plausible mechanism of the L-L transition of water in confinement is proposed in terms of incomplete growth of homogeneous nucleation of ice due to an interfacial free energy effect to inhibit crystallization of water confined in small pores.

Tropical support vector machines: Evaluations and extension to function spaces.

Support Vector Machines (SVMs) are one of the most popular supervised learning models to classify using a hyperplane in an Euclidean space. Similar to SVMs, tropical SVMs classify data points using a tropical hyperplane under the tropical metric with the max-plus algebra. In this paper, first we show generalization error bounds of tropical SVMs over the tropical projective torus. While the generalization error bounds attained via Vapnik-Chervonenkis (VC) dimensions in a distribution-free manner still depend on the dimension, we also show numerically and theoretically by extreme value statistics that the tropical SVMs for classifying data points from two Gaussian distributions as well as empirical data sets of different neuron types are fairly robust against the curse of dimensionality. Extreme value statistics also underlie the anomalous scaling behaviors of the tropical distance between random vectors with additional noise dimensions. Finally, we define tropical SVMs over a function space with the tropical metric.

Methotrexate-induced Subacute Encephalopathy That Showed No Abnormalities on Magnetic Resonance Imaging Soon after Symptom Appearance.

A 21-year-old woman was diagnosed with acute lymphoblastic leukemia. After the administration of intrathecal methotrexate (MTX), the patient experienced dysarthria and paralysis for one hour. Magnetic resonance imaging (MRI) performed one hour from the onset and just before symptoms disappeared revealed no abnormalities. The next day, the symptoms appeared again, and diffusion-weighed MRI revealed a high-intensity area in the left frontal lobe. The patient was diagnosed with MTX-induced encephalopathy. This case suggested that MRI performed as soon as symptoms appear might show normal findings in MTX-induced encephalopathy.

Guillain-Barré syndrome after percutaneous coronary intervention and transcatheter aortic valve implantation.

Guillain-Barré syndrome (GBS) usually develops after preceding infection, but cardiac surgery can also occasionally cause GBS. Currently, cardiac catheterizations have already become common therapeutic options for heart diseases, but there have been no reports of GBS occurrence after that. Herein, we present a rare case in which GBS occurred following catheterization. An 85-year-old-man with sudden onset chest pain was rushed to our hospital and diagnosed with ST-elevated myocardial infarction. He underwent emergent percutaneous coronary intervention (PCI) to left anterior descending artery, but he still had exertional chest pain. Echocardiography revealed severe aortic stenosis (AS) and our heart team considered AS was the cause of symptom and decided to perform and transcatheter aortic valve implantation (TAVI), 11 days after the PCI. However, 5 days after the TAVI procedure, he presented with symmetrical muscular weakness of extremities. Cranial magnetic resonance imaging showed no significant lesion. Based on several signs including albuminocytologic dissociation in cerebrospinal fluid examination, demyelinating polyneuropathy in nerve conduction study, positive anti-ganglioside antibody, and the lack of preceding infection, he was diagnosed with GBS triggered by cardiac catheterizations. We administered high-dose intravenous immunoglobulin therapy and his motor strength gradually improved, finally discharged with full motor strength after 7 months rehabilitation. Learning objective: •Cardiac surgery has been already reported as a non-infectious risk factor of Guillain-Barré syndrome (GBS) in previous literatures, and cardiac catheterization such as percutaneous coronary intervention and transcatheter aortic valve implantation, which were relatively less invasive procedure, may be a potential risk factor for GBS occurrence as well.•If a patient complains of progressive, symmetrical neurological symptoms after cardiac catheterization, GBS should be considered as the possible cause, and nerve conduction study and cerebrospinal fluid examination may be helpful for the diagnosis.

Anti-nuclear matrix protein 2 antibody-positive dermatomyositis with gastrointestinal ulcers: A case report.

Gastrointestinal manifestations are a very rare complication of dermatomyositis (DM) and are much less frequent in adult cases than in juvenile cases. Only a few previous papers have reported adult patients who had DM with anti-nuclear matrix protein 2 (anti-NXP2) antibodies and who developed gastrointestinal ulcers. Herein, we report a similar case of a 50-year-old man who had DM with anti-NXP2 antibodies followed by relapsing multiple gastrointestinal ulcers. Even after the administration of prednisolone, his muscle weakness and myalgia deteriorated and gastrointestinal ulcers relapsed. In contrast, intravenous immunoglobulin and azathioprine improved his muscle weakness and gastrointestinal ulcers. Based on the parallel disease activity of the muscular and gastrointestinal symptoms, we considered that his gastrointestinal ulcers were a complication of DM with anti-NXP2 antibodies. We also propose that early intensive immunosuppressive therapy would be required for the muscular and gastrointestinal symptoms in DM with anti-NXP2 antibodies.

Early detection of cognitive decline in Alzheimer's disease using eye tracking.

Background: Patients with Alzheimer's disease (AD) are known to exhibit visuospatial processing impairment, as reflected in eye movements from the early stages of the disease. We investigated whether the pattern of gaze exploration during visual tasks could be useful for detecting cognitive decline at the earliest stage. Methods: Sixteen AD patients (age: 79.1 ± 7.9 years, Mini Mental State Examination [MMSE] score: 17.7 ± 5.3, mean ± standard deviation) and 16 control subjects (age: 79.4 ± 4.6, MMSE score: 26.9 ± 2.4) participated. In the visual memory task, subjects memorized presented line drawings for later recall. In the visual search tasks, they searched for a target Landolt ring of specific orientation (serial search task) or color (pop-out task) embedded among arrays of distractors. Using video-oculography, saccade parameters, patterns of gaze exploration, and pupil size change during task performance were recorded and compared between AD and control subjects. Results: In the visual memory task, the number of informative regions of interest (ROIs) fixated was significantly reduced in AD patients compared to control subjects. In the visual search task, AD patients took a significantly longer time and more saccades to detect the target in the serial but not in pop-out search. In both tasks, there was no significant difference in the saccade frequency and amplitude between groups. On-task pupil modulation during the serial search task was decreased in AD. The number of ROIs fixated in the visual memory task and search time and saccade numbers in the serial search task differentiated both groups of subjects with high sensitivity, whereas saccade parameters of pupil size modulation were effective in confirming normal cognition from cognitive decline with high specificity. Discussion: Reduced fixation on informative ROIs reflected impaired attentional allocation. Increased search time and saccade numbers in the visual search task indicated inefficient visual processing. Decreased on-task pupil size during visual search suggested decreased pupil modulation with cognitive load in AD patients, reflecting impaired function of the locus coeruleus. When patients perform the combination of these tasks to visualize multiple aspects of visuospatial processing, cognitive decline can be detected at an early stage with high sensitivity and specificity and its progression be evaluated.

Facile formation of barium titanium oxyhydride on a titanium hydride surface as an ammonia synthesis catalyst.

Oxyhydrides are promising compounds as supports for ammonia synthesis catalysts because they suppress hydrogen poisoning on the catalyst surface and enhance the ammonia synthesis activity. Herein, we developed a facile method for preparing BaTiO2.5H0.5, a perovskite oxyhydride, on a TiH2 surface via the conventional wet impregnation method using TiH2 and Ba hydroxide. Scanning electron microscopy and high-angle annular dark-field scanning transmission electron microscopy observations revealed that BaTiO2.5H0.5 crystallized as nanoparticles of ca. 100-200 nm on the TiH2 surface. The Ru-loaded catalyst Ru/BaTiO2.5H0.5-TiH2 exhibited 2.46 times higher ammonia synthesis activity (3.05 mmol-NH3 g-1 h-1 at 400 °C) than the benchmark Ru catalyst Ru-Cs/MgO (1.24 mmol-NH3 g-1 h-1 at 400 °C) because of the suppression of hydrogen poisoning. The analysis of reaction orders showed that the effect of suppressing hydrogen poisoning on Ru/BaTiO2.5H0.5-TiH2 was equivalent to that of the reported Ru/BaTiO2.5H0.5 catalyst, thus supporting the formation of BaTiO2.5H0.5 perovskite oxyhydride. This study demonstrated that the selection of appropriate raw materials facilitates the formation of BaTiO2.5H0.5 oxyhydride nanoparticles on the TiH2 surface using the conventional synthesis method.