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Introduction: Cornelia de Lange syndrome (CdLS) is a rare congenital malformation characterized by distinctive facial features, short stature, and limb defects. In addition, half of the patients with CdLS exhibit repetitive self-injurious behaviors (SIBs) related to intellectual disability with autistic traits. CdLS is caused by pathogenic variants of genes encoding the cohesin complex pathway, with 70% of these variants identified in the nipped-B-like (NIPBL) gene. Case Presentation: We report 2 patients with CdLS who exhibited repetitive SIBs. Patient 1, a 40-year-old male, carried a novel heterozygous duplication variant, c.1458dup, p.(Glu487*), in exon 9 of the NIPBL gene. Patient 2, a 49-year-old female, carried a novel heterozygous insertion variant, c.1751_1752ins[A;1652_1751], p.(Asp584Glufs*8), in exon 10 of the NIPBL gene. These variants were predicted to confer loss of function to the protein because of a premature stop codon. In both patients, single-photon emission computed tomography using N-isopropyl-p-[123I] iodoamphetamine (IMP-SPECT) revealed diffuse hypoperfusion in the cerebellum. Discussion: This report identified 2 novel pathogenic variants in the NIPBL gene and the relationship between SIBs and cerebellar hypoperfusion in patients with CdLS. The cerebellar hypoperfusion might have been caused by the dysfunction of the cohesin complex via the downregulation of the NIPBL gene products. Further studies should be conducted to elucidate the contribution of the NIPBL gene to the development of the cerebello-cerebral cortical circuits associated with behavioral disorders.

We report a long-lived patient with Lafora disease (LD). A 34-year-old woman experienced onset of seizures at the age of 11 years. She was bedridden in her early twenties due to frequent generalized tonic-clonic seizures, myoclonus, and progressive mental deterioration. Her seizures occurred all the time despite administration of multiple anticonvulsants at high doses. At the age of 31, she started perampanel, which resulted in reduction of anticonvulsants after her visible myoclonus and convulsions disappeared. Brain magnetic resonance imaging showed marked cerebral and cerebellar atrophy, and single-photon emission computed tomography using N-isopropyl-p-[123I] iodoamphetamine (IMP-SPECT) revealed significant hypoperfusion of the frontal lobe and cerebellum. We identified a W219R homozygous mutation in exon 1 of the NHLRC1 gene. Because perampanel may not only control seizures but also prevent mental deterioration in LD, we propose that perampanel should be administered from the early stage of LD.

Introduction: Dyggve-Melchior-Clausen syndrome (DMC) is a rare autosomal recessive spondyloepimetaphyseal dysplasia characterized by short stature, microcephaly, intellectual disability, and coarse face. This disorder is caused by pathogenic/likely pathogenic variants of the DYM gene which encodes dymeclin. Case Presentation: Herein, we report a 60-year-old Japanese man who was born to consanguineous parents. He presented with abdominal distention and rectal prolapse in addition to the common features of DMC. We identified a novel homozygous frameshift variant [c.1670delT, p.(Leu557Argfs*20)] in the DYM gene, which introduces a premature stop codon. Histological analysis revealed disarrangement of actin filaments in cultured fibroblasts. Discussion: To the best of our knowledge, this is the first Japanese case of DMC with a confirmed variant in the DYM gene. This report provides more information about the geographic distribution and phenotypic spectrum of DMC. Moreover, it presents a novel DYM variant and insights about DMC pathology that may be associated with the disarrangement of actin filaments.

A 65‐year‐old woman with mutation of the ABCD1 gene for adrenoleukodystrophy (ALD) was admitted to our hospital with a urinary tract infection. Abdominal computed tomography showed dilation of the urinary tract. Although she had noticed pollakisuria since her forties, she had not been followed up by any medical institutions until we diagnosed her as a female carrier with ALD. ALD is an X‐linked pattern of inheritance that typically affects males, but many female carriers actually present slowly progressive myelopathy and neuropathy. Therefore, it is important to identify female carriers with ALD and treat them at the earliest stage possible., Many female adrenoleukodystrophy carriers manifest signs and symptoms of myelopathy and polyneuropathy. Therefore, it is important to identify female carriers with ALD and treat them at the earliest stage possible.

Idiopathic basal ganglia calcification (IBGC) is a rare intractable disease characterized by abnormal mineral deposits, including mostly calcium in the basal ganglia, thalamus, and cerebellum. SLC20A2 is encoding the phosphate transporter PiT-2 and was identified in 2012 as the causative gene of familial IBGC. In this study, we investigated functionally two novel SLC20A2 variants (c.680C > T, c.1487G > A) and two SLC20A2 variants (c.82G > A, c.358G > C) previously reported from patients with IBGC. We evaluated the function of variant PiT-2 using stable cell lines. While inorganic phosphate (Pi) transport activity was abolished in the cells with c.82G > A, c.358G > C, and c.1487G > A variants, activity was maintained at 27.8% of the reference level in cells with the c.680C > T variant. Surprisingly, the c.680C > T variant had been discovered by chance in healthy members of an IBGC family, suggesting that partial preservation of Pi transport activity may avoid the onset of IBGC. In addition, we confirmed that PiT-2 variants could be translocated into the cell membrane to the same extent as PiT-2 wild type. In conclusion, we investigated the PiT-2 dysfunction of four SLC20A2 variants and suggested that a partial reduced Pi transport function of PiT-2 might not be sufficient to induce brain calcification of IBGC.

To clarify the current status of genetic counseling and health monitoring for symptomatic and asymptomatic female carriers of dystrophinopathy (Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD)), we sent out questionnaires to 104 member institutions of The Japan's National Liaison Council for Clinical Sections of Medical Genetics, and responses were received from 51 institutions. Between April 2013 and March 2014, 57 carriers at 21 institutions received genetic counseling, and 37 carriers at 15 institutions underwent genetic screening for DMD/BMD mutations. At the 23 institutions that gave genetic counseling, 20 (87%) informed carriers of possible health problems, 14 (61%) informed carriers of cardiomyopathy and heart failure, and 14 (61%) advised carriers about regular medical checkups. Evidence based on accurate and up-to-date epidemiological studies of female carriers is needed and should be widely shared with the families, medical providers, and society.

Many claim that they do not have enough neurologists in Japan, but supply and demand of neurologists remains to be analyzed. To investigate the recruitment for the Japanese Society of Neurology (JSN), the subcommittee of JSN for education performed a questionnaire-based survey in 80 medical universities and 271 board-certified education facilities throughout Japan. The response rate to the questionnaire was 77.5% in medical universities and 42.4% in education facilities. It was shown that each department of neurology in university recruits average 2.2 doctors, while they supposed that more than 4 doctors to be recruited every year. The questionnaire survey included what measures JSN should take in order to promote recruitment for JSN.

Objective This study attempted to clarify the current status of female dystrophinopathy carriers, including the numbers of patients, the status of genetic screening, the status of counseling, physicians' understanding, and barriers to registration. Methods We sent out questionnaires to 402 physicians registered in the Remudy dystrophinopathy registry. The total number of responses received was 130 (response rate: 32%). Result In total, 1,212 cases of Duchenne muscular dystrophy, 365 cases of Becker muscular dystrophy, and 132 cases of female dystrophinopathy with a confirmed genetic mutation were encountered, and genetic testing was performed in the mother in 137, 23, and 12 cases, respectively. With respect to the risk of the onset of health problems, 25% of physicians always explained, 29% usually explained, 29% sometimes explained, and 13% never explained the risk to the mothers and female siblings of dystrophinopathy patients. The most common reason for not explaining the risk was a lack of knowledge/information. Thirty-five percent were familiar with the guidelines for testing the heart function of carriers. Conclusion Fewer mothers of dystrophinopathy patients have undergone genetic testing in Japan than in other countries. A significant portion of doctors did not explain the risks of health problems due to a lack of knowledge. We hope this survey will lead to an increased discussion of female dystrophinopathy patients.

To understand the status of postgraduate education in neurology in Japan, the Committee for the Education of Undergraduate Students and Junior Residents within the Japanese Society of Neurology investigated the four-year trend at 80 medical schools from 2009 to 2012. The mean number of new students to each postgraduate school increased from 1.24 to 1.67 during these four years. After training clinical neurology, more than half of the neurological residents entered the postgraduate schools. Students in the postgraduate schools seemed to be researching major neurological diseases using various methods at each neurology laboratory. However, some problems were suggested. First, the mean number of newcomers to the neurology departments of the universities decreased gradually from 2.29/year to 1.96/year. Second, many of the postgraduate students were working in patient services at university hospitals or as part-time workers at other hospitals, and may not have sufficient time for their research projects. Third, many of the postgraduate students were carrying out research at each affiliated department of neurology, and may not have the opportunity to work in laboratories specializing in basic science. Finally, there may not be sufficient opportunities for further research at other laboratories in Japan or overseas after they finished their work at postgraduate school.

Lymphoma causes various neurological manifestations that might affect any part of the nervous system and occur at any stage of the disease. The peripheral nervous system is one of the major constituents of the neurological involvement of lymphoma. In this study we characterized the clinical, electrophysiological and histopathological features of 32 patients with neuropathy associated with non-Hodgkin’s lymphoma that were unrelated to complications resulting from treatment for lymphoma. Nine patients had pathologically-proven neurolymphomatosis with direct invasion of lymphoma cells into the peripheral nervous system. These patients showed lymphomatous cell invasion that was more prominent in the proximal portions of the nerve trunk and that induced demyelination without macrophage invasion and subsequent axonal degeneration in the portion distal from the demyelination site. Six other patients were also considered to have neurolymphomatosis because these patients showed positive signals along the peripheral nerve on fluorodeoxyglucose positron emission tomography imaging. Spontaneous pain can significantly disrupt daily activities, as frequently reported in patients diagnosed with neurolymphomatosis. In contrast, five patients were considered to have paraneoplastic neuropathy because primary peripheral nerve lesions were observed without the invasion of lymphomatous cells, with three patients showing features compatible with chronic inflammatory demyelinating polyneuropathy, one patient showing sensory ganglionopathy, and one patient showing vasculitic neuropathy. Of the other 12 patients, 10 presented with multiple mononeuropathies. These patients showed clinical and electrophysiological features similar to those of neurolymphomatosis rather than paraneoplastic neuropathy. Electrophysiological findings suggestive of demyelination were frequently observed, even in patients with neurolymphomatosis. Eleven of the 32 patients, including five patients with neurolymphomatosis, fulfilled the European Federation of Neurological Societies/Peripheral Nerve Society electrodiagnostic criteria of definite chronic inflammatory demyelinating polyneuropathy. Some of these patients, even those with neurolymphomatosis, responded initially to immunomodulatory treatments, including the administration of intravenous immunoglobulin and steroids. Patients with lymphoma exhibit various neuropathic patterns, but neurolymphomatosis is the major cause of neuropathy. Misdiagnoses of neurolymphomatosis as chronic inflammatory demyelinating polyneuropathy are frequent due to a presence of a demyelinating pattern and the initial response to immunomodulatory treatments. The possibility of the concomitance of lymphoma should be considered in various types of neuropathy, even if the diagnostic criteria of chronic inflammatory demyelinating polyneuropathy are met, particularly in patients complaining of pain. * Abbreviations : CIDP : chronic inflammatory demyelinating polyneuropathy EFNS/PNS : European Federation of Neurological Societies/Peripheral Nerve Society FDG : fluorodeoxyglucose IVIg : intravenous immunoglobulin

Nasu-Hakola disease (NHD) is a rare autosomal recessive disorder, characterized by progressive presenile dementia and formation of multifocal bone cysts, caused by a loss-of-function mutation of DNAX-activation protein 12 (DAP12) or triggering receptor expressed on myeloid cells 2 (TREM2). TREM2 and DAP12 constitute a receptor/adaptor complex on myeloid cells. The post-receptor signals are transmitted via rapid phosphorylation of the immunoreceptor tyrosine-based activating motif (ITAM) of DAP12, mediated by Src protein tyrosine kinases, followed by binding of phosphorylated ITAM to Src homology 2 (SH2) domains of spleen tyrosine kinase (Syk), resulting in autophosphorylation of the activation loop of Syk. To elucidate the molecular mechanism underlying the pathogenesis of NHD, we investigated Syk expression and activation in the frontal cortex and the hippocampus of three NHD and eight control brains by immunohistochemistry. In NHD brains, the majority of neurons expressed intense immunoreactivities for Syk and Y525/Y526-phosphorylated Syk (pSyk) chiefly located in the cytoplasm, while more limited populations of neurons expressed Src. The levels of pSyk expression were elevated significantly in NHD brains compared with control brains. In both NHD and control brains, substantial populations of microglia and macrophages expressed pSyk, while the great majority of reactive astrocytes and myelinating oligodendrocytes did not express pSyk, Syk or Src. These observations indicate that neuronal expression of pSyk was greatly enhanced in the cerebral cortex and the hippocampus of NHD brains, possibly via non-TREM2/DAP12 signaling pathways involved in Syk activation.

Nakajo-Nishimura syndrome (NNS) is a disorder that segregates in an autosomal recessive fashion. Symptoms include periodic fever, skin rash, partial lipomuscular atrophy, and joint contracture. Here, we report a mutation in the human proteasome subunit beta type 8 gene (PSMB8) that encodes the immunoproteasome subunit β5i in patients with NNS. This G201V mutation disrupts the β-sheet structure, protrudes from the loop that interfaces with the β4 subunit, and is in close proximity to the catalytic threonine residue. The β5i mutant is not efficiently incorporated during immunoproteasome biogenesis, resulting in reduced proteasome activity and accumulation of ubiquitinated and oxidized proteins within cells expressing immunoproteasomes. As a result, the level of interleukin (IL)-6 and IFN-γ inducible protein (IP)-10 in patient sera is markedly increased. Nuclear phosphorylated p38 and the secretion of IL-6 are increased in patient cells both in vitro and in vivo, which may account for the inflammatory response and periodic fever observed in these patients. These results show that a mutation within a proteasome subunit is the direct cause of a human disease and suggest that decreased proteasome activity can cause inflammation.

Nasu-Hakola disease (NHD) is a rare autosomal recessive disorder, characterized by progressive presenile dementia and formation of multifocal bone cysts, caused by genetic mutations of DNAX-activation protein 12 (DAP12) or triggering receptor expressed on myeloid cells 2 (TREM2). TREM2 and DAP12 constitute a receptor/adapter signaling complex expressed on osteoclasts, dendritic cells (DC), macrophages and microglia. Previous studies using knockout mice and mouse brain cell cultures suggest that a loss-of-function of DAP12/TREM2 in microglia plays a central role in the neuropathological manifestation of NHD. However, there exist no immunohistochemical studies that focus attention on microglia in NHD brains. To elucidate a role of microglia in the pathogenesis of NHD, we searched NHD-specific biomarkers and characterized their expression on microglia in NHD brains. Here, we identified allograft inflammatory factor 1 (AIF1, Iba1) and sialic acid binding Ig-like lectin 1 (SIGLEC1) as putative NHD-specific biomarkers by bioinformatics analysis of microarray data of NHD DC. We studied three NHD and eight control brains by immunohistochemistry with a panel of 16 antibodies, including those against Iba1 and SIGLEC1. We verified the absence of DAP12 expression in NHD brains and the expression of DAP12 immunoreactivity on ramified microglia in control brains. Unexpectedly, TREM2 was not expressed on microglia but expressed on a small subset of intravascular monocytes/macrophages in control and NHD brains. In the cortex of NHD brains, we identified accumulation of numerous Iba1-positive microglia to an extent similar to control brains, while SIGLEC1 was undetectable on microglia in all the brains examined. These observations indicate that human microglia in brain tissues do not express TREM2 and DAP12-deficient microglia are preserved in NHD brains, suggesting that the loss of DAP2/TREM2 function in microglia might not be primarily responsible for the neuropathological phenotype of NHD.

Aims: Sporadic amyotrophic lateral sclerosis (SALS) seems to be a multifactorial disease, the pathogenesis of which may involve both genetic and environmental factors. The present study aims at identifying a possible genetic change that confers risk for SALS. Methods: We performed whole-genome screening of a copy-number variation (CNV) using a CNV beadchip, followed by real-time quantitative polymerase chain reaction (qPCR) and region-targeted high-density oligonucleotide tiling microarray. Results: Within the 40-kb region on 10p15.3 subtelomere, which harbours two genes encoding isopentenyl diphosphate isomerase 1 (IDI1) and IDI2, we found a segmental copy-number gain in a large proportion of SALS patients. qPCR analysis demonstrated the copy-number gain in 46 out of 83 SALS patients, as compared with 10 out of 99 controls (p = 4.86 × 10−11, Odds Ratio 10.8); subsequent tiling microarray validated qPCR results and elucidated the fine structure of segmental gains. Conclusions: A segmental copy-number gain in the IDI1/IDI2 gene region may play a significant role in the pathogenesis of SALS.

A 67-year-old man with a portal-systemic shunt confirmed by three-dimensional computed tomography (3D-CT) was successfully treated by percutaneous vascular embolization. The patient had aggravated loss of memory, disorientation, and hyperammonemia. A gastrorenal shunt 16 mm in diameter was found by 3D-CT reconstructed by helical computed tomography (CT). Embolization was performed only in the shunt percutaneously through the inferior vena cava. One year after the embolization, no recurrence of portal-systemic encephalopathy and no portal hypertension have appeared, and the clinical course has been good.

Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a neurodegenerative disorder first described among French Canadians in Quebec. To date, 24 mutations have been reported in the SACS gene of ARSACS patients. The authors report a clinical and genetic analysis of a Japanese family with ARSACS with novel compound heterozygous mutations in the SACS gene (N161fsX175, L802P). The phenotype is similar to that of previously reported ARSACS patients.

Myofibrillar myopathies (MFM) involve accumulation of various proteins in the muscle cytoplasm. In myopathy with a heterozygous A337P mutation of the desmin gene, electron-micrographs showed aggregates of vesicular and tubular structures. Positive cytoplasmic reaction for caveolin-3 immunohistochemistry and cholera toxin B binding suggested that caveolae comprised some of the aggregates. As caveolae occur in the Golgi complex and are transported to the cell surface, the results suggest inhibition of their trafficking to the sarcolemma. Alternatively, they could be trapped during internalization. We hypothesize that the accumulation of multiple proteins in MFM could be partially due to inhibited intracellular trafficking.

We genetically screened patients with ataxia with ocular motor apraxia type 1 (AOA1)/early-onset ataxia with ocular motor apraxia and hypoalbuminemia (EAOH), with a Japanese variant form of Friedreich’s ataxia. Three patients were found to have a homozygous insertion mutation of the aprataxin gene (689insT). An elder sister of a patient in this series died of cerebral hemorrhage at the age of 45, and underwent autopsy. In her cerebellar cortex, the mean density of Purkinje cells in the flocculus had predominantly decreased to 6.7% of normal controls, whereas the Purkinje cells in the other areas of the cerebellar hemisphere had decreased to 78.2%. This suggests that the cerebellar flocculus is the primary affected lesion in AOA1/EAOH, which should be associated with ocular motor apraxia.

Ca 2+ -ATPase of sarcoplasmic reticulum is an ATP-powered Ca 2+ pump but also a H + pump in the opposite direction with no demonstrated functional role. Here, we report a 2.4-Å-resolution crystal structure of the Ca 2+ -ATPase in the absence of Ca 2+ stabilized by two inhibitors, dibutyldihydroxybenzene, which bridges two transmembrane helices, and thapsigargin, also bound in the membrane region. Now visualized are water and several phospholipid molecules, one of which occupies a cleft between two transmembrane helices. Atomic models of the Ca 2+ binding sites with explicit hydrogens derived by continuum electrostatic calculations show how water and protons fill the space and compensate charge imbalance created by Ca 2+ -release. They suggest that H + countertransport is a consequence of a requirement for maintaining structural integrity of the empty Ca 2+ -binding sites. For this reason, cation countertransport is probably mandatory for all P-type ATPases and possibly accompanies transport of water as well.

A 77-year-old Japanese man with a 14-year history of human T-cell lymphotropic virus type I-associated myelopathy developed pancytopenia, proteinuria, renal dysfunction, and hypocomplementemia. Antinuclear antibody and anti-double-stranded DNA antibody test results were positive, and circulating immune complexes were detected. A renal biopsy showed diffuse and global mesangiocapillary proliferation with extensive subendothelial deposits. Immunofluorescence microscopy showed strong granular staining for immunoglobulins and complements in the mesangium and along capillary walls. Electron microscopy showed numerous mesangial and subendothelial electron-dense deposits. From these findings, systemic lupus erythematosus and diffuse global lupus nephritis were diagnosed. This is a rare case of a patient developing lupus nephritis during the long-term course of human T-cell lymphotropic virus type I-associated myelopathy.

2004年9月から11月にかけて日本海側北部を中心に, 原因不明の急性脳炎 (脳症) が多発した. 多くの患者は末期腎障害があり, スギヒラタケを摂取していたという共通事項があった. 秋田県では23例の届け出があった. 23例中16例は慢性透析患者であり, 血液透析患者であることとスギヒラタケ摂取が共通事項であることを私たちは報告してきた. 本研究は透析患者における急性脳症発症の危険因子を明らかにするため, 急性脳症発症例と非発症例の臨床背景やスギヒラタケ摂取の有無を比較検討した. 16名の急性脳症患者と秋田県内在住1,674名の脳症非発症透析患者について透析施設に質問用紙を郵送した. 16名の脳症患者と1,236名 (非脳症例中の73.8%) の非発症透析患者, 計1,252名から回答を得た. 16名の急性脳症例のうち, スギヒラタケ摂取が明らかであったのは14名, 不明は2名であった, 1,252名の透析患者中573名 (45.8%) がスギヒラタケを摂取し, 573名中14例 (2.4%) が急性脳症となった. 急性脳症16例のうち6例 (37.5%) が死亡した. 明らかにスギヒラタケを摂取していない患者で, 急性脳症を発症した例はなかった. 急性脳症発症例と非発症例を比較すると, 年齢, 性, 透析期間, 透析法に差はなかった. 単変量解析では, 糖尿病 (p=0.040, オッズ比3.10) とスギヒラタケ摂取者 (p=0.010, オッズ比8.63) の頻度が急性脳症発症例に多かった. 本研究結果からスギヒラタケ摂取は急性脳症発症の重要な危険因子であることが示唆された. スギヒラタケが含有していると考えられる原因物質解明のため, さらなる検討が必要である.

We report a paraneoplastic neuropathy with severe motor involvement following sensory-ataxic disturbance. Anti-disialosyl immunoglobulin M (IgM) antibody was detected in the course of malignant lymphoma of diffuse large B-cell type, which usually spares the motor system. Onset was subacute, with relapsing and remitting sensory ataxia, muscle weakness, bulbar palsy, respiratory paralysis, and ophthalmoplegia; only neck rotation was retained in the terminal stage. Autopsy showed no lymphoma cells infiltrating the nervous system. Motor neurons survived in the spinal cord, but mean diameter of the ventral spinal nerve roots was reduced considerably. The gracile fasciculus and the sural nerve were more markedly degenerated than proximal portions. Morphometric study showed that most of the proximal motor and sensory axons did not extend distally. This autopsy report provides further definition of a neuropathy associated with malignant lymphoma and IgM antibodies against disialosyl residues.

2004年9月から11月にかけて新潟, 山形や秋田を中心に, 原因不明の急性脳炎 (脳症) が多発した. 多くの患者は末期腎障害があり, スギヒラタケを摂取していたという共通事項があった. 秋田県では24例の届け出があった. 24例中17例は慢性透析患者であり, 3例は保存期腎不全であった. 本研究は17例の脳症発症透析患者において, 何らかの共通した臨床背景や透析条件が急性脳症発症に影響しているかを検討した. その結果, 平均年齢64.2歳, 平均透析期間56.8か月, 男性9女性8, 腎不全の主たる原因疾患は糖尿病性腎症と慢性腎炎であった. 17例の共通事項は, 血液透析患者であることとスギヒラタケ摂取だけであった. 服用薬剤, 透析液, 抗凝固剤や透析膜に特徴的なものはなかった. さらに, 2施設102名の透析患者を調査し, スギヒラタケ摂取率と急性脳症発症率を検討した. 102名中57名 (55.8%) がスギヒラタケを摂取し, 57名中5例 (8.7%) が急性脳症を発症, 5例中2例 (40.0%) が急性脳症によって死亡した. 本調査では血液透析とスギヒラタケ摂取以外に, 他に共通した臨床背景や透析条件は見い出すことができなかった. 原因究明のためのさらなる検討が必要である.

Prevalence rate of Clostridium difficile in healthy human adults is believed to be very low. Our RT-PCR system using glass powder, which can eliminate PCR inhibitors, detected C. difficile toxin B mRNA in 16 of 30 fecal samples (53.3%) from healthy human adults. In contrast, we failed to detect toxin B in the same fecal samples by PCR using DNA templates extracted with phenol-chloroform. Our results suggest that PCR inhibitors in feces carried through phenol-chloroform extraction procedure might suppress the sensitivity of PCR and that C. difficile is actually present in human gut microbiota more frequently than previously suspected.

Despite the unknown etiology and pathogenesis of sporadic inclusion body myositis (s-IBM), investigators have speculated that the lysosome system in muscle fiber plays a central role in rimmed vacuole formation, a hallmark of s-IBM. We explored the role of receptor-mediated intracellular transport and autophagy in the lysosomal system in the abnormal accumulation of rimmed vacuoles in s-IBM. Expressions of mannose 6-phosphate receptor (M6PR), clathrin and hApg5 and hApg12 were analyzed in muscle biopsy specimens from patients with s-IBM, amyotrophic lateral sclerosis (ALS) or peripheral neuropathy and in normal human muscle specimens by means of immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR). Most muscle fibers in control specimens showed little or no immunoreactivity for clathrin and M6PR, which are involved in the receptor-mediated intracellular transport. Abnormal increases in both proteins were observed mainly in the sarcoplasm of atrophic fibers in all diseased specimens. In s-IBM muscles in particular, clathrin and M6PR were often observed inside rimmed vacuoles and in the sarcoplasm of vacuolated or non-vacuolated fibers. mRNA levels of hApg5 and hApg12, which are involved in autophagic vacuole formation, as well as of M6PR and clathrin were significantly increased in s-IBM muscles in comparison to levels in normal and ALS/peripheral neuropathy muscles. Our results suggest that the transport of newly synthesized lysosomal enzymes from the secretory pathway via the trans-Golgi network of the Golgi apparatus and autophagic vacuole formation (i.e., autophagy) in the lysosome system are activated in s-IBM muscles. Remarkable accumulation of rimmed vacuoles is thought to occur because of abnormal lysosome function, especially the formation or turnover of autolysosomes after the fusion of autophagic vacuoles with the early endosomes or because of the increase in the rate of muscle fiber breakdown.

We have characterized the biochemical properties of the testis and brain-specific 105-kDa protein which is cross-reacted with an anti-bovine HSP90 antibody. The protein was induced in germ cells by heat stress, resulting in a protein which is one of the heat shock proteins [Kumagai, J., Fukuda, J., Kodama, H., Murata, M., Kawamura, K., Itoh, H. & Tanaka, T. (2000) Eur. J. Biochem.267, 3073–3078]. In the present study, we characterized the biochemical properties of the protein. The 105-kDa protein inhibited the aggregation of citrate synthase as a molecular chaperone in vitro. ATP/MgCl2 has a slight influence of the suppression of the citrate synthase aggregation by the 105-kDa protein. The protein possessed chaperone activity. The protein was able to bind to ATP–Sepharose like the other molecular chaperone HSP70. A partial amino-acid sequence (24 amino-acid residues) of the protein was determined and coincided with those of the mouse testis- and brain-specific APG-1 and osmotic stress protein 94 (OSP94). The 105-kDa protein was detected only in the medulla of the rat kidney sections similar to OSP94 upon immunoblotting. The purified 105-kDa protein was cross-reacted with an antibody against APG-1. These results suggested that APG-1 and OSP94 are both identical to the 105-kDa protein. There were highly homologous regions between the 105-kDa protein/APG-1/OSP94 and HSP90. The region of HSP90 was also an immunoreactive site. An anti-bovine HSP90 antibody may cross-react with the 105-kDa protein similar to HSP90 in the rat testis and brain. We have investigated the localization and developmental induction of the protein in the rat brain. In the immunohistochemical analysis, the protein was mainly detected in the cytoplasm of the nerve and glial cells of the rat brain. Although the 105-kDa protein was localized in all rat brain segments, the expression pattern was fast in the cerebral cortex and hippocampus and slow in the cerebellum.

Polyglutamine (polyQ) aggregate bodies are a hallmark of dentatorubral-pallidoluysian atrophy and related neurodegenerative disorders, although the relationship between aggregate body formation and cell death is not clear. We analyzed the kinetics of polyQ aggregate formation and the time intervals for cell death, tracking individual cells using fluorescence video microscopy, for the first time. Expanded polyQ tracts of atrophin-1 with or without nuclear localization signal (NLS) labeled with green fluorescent protein (GFP) were constructed, Q57NLS/GFP and Q56/GFP, respectively. All of the Q57NLS/GFP aggregate bodies were in nuclei, and all of the Q56/GFP aggregate bodies were in cytoplasm. Aggregates of Q56/GFP were larger than those of Q57NLS/GFP. Surprisingly, a kinetic analysis showed that the latter grew 5.37 times faster than the former. The time interval between transfection and cell death was shorter in Q57NLS/GFP, but the time between the end of the rapid growing phase of aggregation and the start of the cell death process did not show a significant difference. Aggregate growth was confirmed to correspond to the accumulated free polyQ by the time of starting aggregation. These findings suggest that aggregate body formation induced by expanded polyQ stretches is a self-limiting process and is enhanced by factor(s) in nuclei, whereas it is not tightly bound to the cell death process. © 2002 Wiley-Liss, Inc.

To investigate the need for pre- and post-graduate education for neurologists, the subcommittee of the Japanese Society of Neurology for education performed a questionnaire-based survey in 80 medical universities throughout Japan. The response rate to the questionnaire was 82.5%. Textbooks for lectures for medical students were used in only 22.7% of those universities. If the Japanese Society of Neurology (JSN) made a standard text, 77.8% of universities would like to use it. Most of the training programs for residents were compatible with the minimum requirements of the JSN. Just 66.7% of those training programs were completed in their own institute, and 77.3% of universities required help from the JSN.

To evaluate postgraduate neurological education, a questionnaire-based survey regarding junior and senior doctor-in-training and the Board Certification Examination in Neurology was carried out on the training supervisors of 690 insitutes, excluding 80 university hospitals. The institutes included 243 teaching hospitals, 326 semi-teaching hospitals and 121 education-associated institutes authorized by the Japanese Society of Neurology (JSN). The results were obtained from 388 institutes, and the response rate was 56.2%. The percentage of junior doctors-in-training that received training in neurology was 68.6% (the average of 2.1 months during 2 years). More than half of the institutes did not have any teaching programs for junior doctors-in-training who did not train in neurology. In senior doctors-in-training, the number of senior doctors-in-trainings per year per institute was 0.44 and was only able to experience limited types of disorders. Also, many institutes could not achieve training goals by the institutes themselves (56%). The problems were due to lack of teaching staffs and manpower, and there were many requests to the Society regarding training methods. As for the Board Certification Examination in Neurology by the Society, it was revealed that there were small number of candidates per year per institute, and over half of institutes could not sufficiently teach and support them. Most requests to the Society were regarding teaching seminars and hands-on courses, and some institutes asked small group meetings for arts and techniques of neurology to be held the Regional Society. In conclusion, there are problems that cannot be solved by individual institutes alone, and we need procedures for postgraduate training in neurology that is organized by the Regional and JSN working as the central organization.

Gait analysis was performed in patients with various vestibular systems using a tactile sensor. There were 4 patients with vestibular neuronitis, 6 patients with large acoustic neuroma and 6 patients with spino-cerebellar degeneration (SCD). Gait phase related parameters such as stance, swing and double support were studied to assess gait stability. Also the area ratio of trajectories of center of force during stance and progression of foot pressure were checked. The calculated value of each variable became high in pathological cases compared with normal controls, and the highest value was obtained in the SCD group. As regards the effect of visual deprivation on stability of gait, the most striking change was found in the large acoustic neuroma group. In a case with a unilateral lesion such as vestibular neuronitis and large acoustic neuroma, foot pressure was greater on the lesion side, especially during gait with eyes closed. As for the foot pressure progression curve, the SCD group showed the most irregular pattern in general, although there were some individual variations. Those results could reflect a functional disorder of the gait control system caused by each disease. Significance of gait analysis is also discussed.

Objective: To determine the cause and pathogenic mechanisms of a 21-year-old patient’s cardioskeletal myopathy. The patient’s muscle atrophy and weakness began in distal parts of limbs; cardiac and facial muscles were later involved. Background: Desmin myopathy is a skeletal myopathy often associated with cardiomyopathy, caused by mutations in the desmin gene and characterized by desmin accumulation in affected muscle fibers, a leading marker of myofibrillar myopathies. Two kinds of deletions and seven missense mutations in the desmin gene have been identified. Methods: Clinical examination, electron microscopy of muscle tissue, two-dimensional gel electrophoresis, DNA sequencing, restriction enzyme analysis, and gene transfection were performed. Results: Electron microscopy showed disruption of sarcomeres at Z discs and electron-dense aggregates in biopsied skeletal and heart muscle. Two-dimensional gel electrophoresis of the patient’s skeletal muscle proteins showed massive accumulation of desmin. The authors identified a novel desmin mutation, L385P in one allele in the carboxyl end of the rod domain 2B in the patient’s leukocytes and skeletal muscle; neither parent had the mutation. Serologic study and DNA markers confirmed the de novo mutation. A peptide harboring desmin rod domains 2A and 2B with L385P tagged with green fluorescent protein induced cytoplasmic aggregates, nuclear DNA condensation, and cell death. Conclusions: A novel de novo mutation, L385P, causes desmin myopathy. An expression study indicated the toxic effect of the L385P mutation.

Quiver (Quv) is a non-sense mutation of neurofilament protein L subunit (NF-L) that causes neurofilament deficiency with preserved microtubules in Japanese quail. Anti-NF-M and anti-NF-H mAbs stained cell bodies of motor neurons in Quv embryo spinal cords much more intense than those in control spinal cords. Volume of motor neurons in Quv spinal cords increased to 2.3 times of control motor neurons. Immunoblot of Quv spinal cords revealed a relative increase in non- and hypo-phosphorylated NF-M and NF-H, and a decrease in the total amount of NFs. Quv sciatic nerves showed faintly reacted phosphorylated NF-M and NF-H. These results suggest that deficiency of assembled neurofilament results in decreased axonal transport of NFs and accumulation of NFs in cell bodies of spinal motor neurons.

To investigate the clinical range of spinocerebellar ataxia type 6 (SCA6), we screened CAG repeat expansion in the voltage-dependent alpha 1A calcium channel gene (CACNL1A4) in 71 ataxic patients in 60 families; 54 patients in 43 families with hereditary ataxia and 17 sporadic patients. Thirteen patients with SCA6 were detected to have elongated CAG in CACNL1A4. Of these, 7 patients had been diagnosed as having hereditary cerebellar cortical atrophy, and 6 patients had been found to have sporadic occurrence. One patient showed distinct pontine atrophy with prominent horizontal or oblique gaze nystagmus which is an unusual feature in sporadic olivopontocerebellar atrophy. For the efficient screening of SCA6, we would propose testing CAG repeat expansion in CACNL1A4, in patients with one of two markers: (1) horizontal or oblique gaze nystagmus without other eye movement disorders, (2) pure cerebellar atrophy, even if occurrence is sporadic. We should note that the pontine atrophy could also be caused by CAG repeat expansion in CACNL1A4.

We tested the effects of four bile acids, taurochenodeoxycholate, taurocholate, tauroursodeoxycholate and taurodeoxycholate, on kinesin-driven microtubule motility, which may have a major influence on membrane organelle transport in cholestasis. Reconstituted microtubules were incubated with kinesin purified from rabbit liver and brain. Binding and gliding of microtubules were visualized by video-enhanced differential interference contrast microscopy. Liver and brain kinesin produced similar microtubule gliding velocities. The effect of bile acids on liver and brain kinesin was also similar. Low concentrations of the four bile acids (0.25–0.5 mM) enhanced the speed of microtubule gliding by up to 152%. Higher concentrations of taurochenodeoxycholate and taurodeoxycholate inhibited attachment, but did not slow the speed of gliding. Detachment was inhibited by the addition of tauroursodeoxycholate. ATPase activity showed no changes in the presence of low concentrations of tauroursodeoxycholate and taurochenodeoxycholate. Triton X-100, a nonionic detergent, increased microtubule gliding by up to 147% at lower concentrations, while higher concentrations (up to 5%) caused a return to normal speed without detachment. Low concentrations of bile acids in hepatocytes may enhance kinesin-driven microtubule dependent organelle transport. In contrast, higher concentrations of toxic bile acids, chenodeoxycholate and deoxycholate, associated with cholestasis may inhibit kinesin-driven motility by detaching microtubules from kinesin.

Dibutyryl cyclic AMP (DBcAMP) is an analogue of cAMP. DBcAMP has many effects on hepatocellular carcinoma, liver cirrhosis, ischemic liver failure and endotoxin-induced inflammatory liver injury. However, little is known about the mechanism of DBcAMP action in Kupffer cells. We examined the effects of DBcAMP on phagocytic activity and production of nitric oxide (NO) and tumor necrosis factor- α (TNF- α ) in cultured rat Kupffer cells treated with lipopolysaccharide (LPS). NO concentrations in culture supernatants were measured using an NO analyzer and TNF- α levels were measured with ELISA. Immunofluorescent staining for nuclear factor- κ B (NF- κ B) was visualized using an anti-NF- κ B p65 antibody. DBcAMP premedication had no effect on LPS-stimulated phagocytic activity of Kupffer cells but increased NO production and inhibited TNF- α production in a dose-dependent manner. Genistein did not block, but H-89 did block, the inhibitory effect of DBcAMP on LPS-stimulated TNF- α production in Kupffer cells. We conclude that DBcAMP inhibits LPS-stimulated TNF- α production by activating cyclic AMP-dependent protein kinase. Using immunofluorescent staining for NF- κ B, we demonstrate that the effect of DBcAMP does not involve signal transduction through NF- κ B.

Kinectin has been identified as a kinesin receptor on endoplasmic reticulum (ER). The ER membrane binding domain of kinectin is still obscure and is thought to require a half of the molecule. To determine the ER insertion site, we produced several constructs around N-terminus of kinectin connected with green fluorescent protein (GFP) and visualized the distribution in Cos-7 cells. The fragment of residues 7-29 appeared in the reticular pattern exactly colocalized with the ER marker but did not remain for a long time. On the other hand, residues 1-106 maintained a reticular pattern for more than seven days. These results indicate that residues 7-29 of kinectin are sufficient for targeting to the ER membrane but insufficient for remaining on the ER.

In ballooned hepatocytes associated with alcoholic liver disease, secretory proteins are abundant, possibly due to an impairment of the microtubule-dependent vesicular transport system. We studied the effects of ethanol and acetaldehyde on microtubules and hepatic kinesin function. Tubulin and microtubule-associated protein 2 was purified by phosphocellulose and hydroxyapatite column chromatography from microtubule proteins of bovine brain. Hepatic kinesin was purified from rabbit liver. The assembly of microtubules was quantified by spectro-photometer. The kinesin motility assay is done with or without various concentrations of ethanol or acetaldehyde using video-enhanced differential interference contrast microscopy. Ethanol had no effect on the assembly or disassembly of the microtubules or on hepatic kinesin function, even at high concentrations of up to 100 mM. In contrast, acetaldehyde reduced hepatic kinesin function at concentrations greater than or equal to 100 μ M and induced microtubular disassembly at concentrations greater than or equal to 200 μ M. In alcoholic liver injury, chronic reduction of hepatic kinesin function may cause retention of secretory proteins and hepatocyte swelling. Moreover, reduction of the microtubule concentrations due to acetaldehyde may further impair the vesicular transport system and reduce the cells ability to maintain morphology, in turn accelerating hepatocyte ballooning.

Kinesin is a major molecular motor responsible for anterograde axonal transport. Chicks were injected with β , β ′-iminodipropionitrile (IDPN) to induce axonal swellings in spinal motor neurons and spinal sensory ganglion neurons. Cylindrical swollen axons were found in the anterior horn and anterior funiculus of the spinal cord, anterior root, and spinal ganglia. All of the axonal swellings were heavily stained with two anti-kinesin monoclonal antibodies. The swellings were mildly stained with an anti-cytoplasmic dynein and anti-tubulin antibodies, and weakly stained with an anti-tau antibody. These suggest the isolated disturbance of kinesin transport with neurofilament accumulation in IDPN intoxication.

Peripheral myelin protein 22 (PMP22), a membrane glycoprotein, plays a significant role in the formation and/or maintenance of compact myelin in the peripheral nervous system. We studied two pedigrees with Dejerine-Sottas disease and identified two novel mutations in the PMP22 gene: one a 2-bp deletional mutation at nucleotide positions 426 and 427 of exon 4 (this is predicted to alter the reading frame at leucine 80 and thus to lead to frame-shifted translation), and the other a guanine to thymine substitution at nucleotide position 636 leading to a cysteine substitution for glycine 150. Both mutations were located in the putative transmembrane domains reported in many cases of Charcot-Marie-Tooth neuropathy, Dejerine-Sottas disease, and hereditary neuropathy with liability to pressure palsies. The results suggest an important role for the putative transmembrane domains of PMP22 in its function.