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K Kamakura

Publications and source records attributed to K Kamakura.

At least 19 recordsLinked to original sources
PubMed2006

Anti-ganglioside complex antibodies associated with severe disability in GBS.

Ganglioside complexes (GSCs) are known as target antigens in Guillain-Barré syndrome (GBS). To elucidate the clinical importance of the anti-GSC antibodies in GBS, we investigated serum antibodies to GSCs containing two of the gangliosides, GM1, GD1a, GD1b and GT1b, and analyzed clinical features of anti-GSC-positive GBS patients. Thirty-nine (17%) of 234 GBS patients had IgG anti-GSC antibodies. Anti-GSC-positive GBS had antecedent gastrointestinal infection and lower cranial nerve deficits more frequently than control GBS. The presence of antibody specificity to GD1a/GD1b and/or GD1b/GT1b was significantly associated with severe disability and a requirement for mechanical ventilation.

Adult↗
PubMed2006

Anti-ganglioside complex antibodies in Miller Fisher syndrome.

BACKGROUND: Some ganglioside complexes (GSCs) are target antigens for serum antibodies in patients with Guillain-Barré syndrome (GBS). Anti-GSC antibodies may be associated with particular clinical features of GBS. OBJECTIVE: To investigate antibodies to GSCs in the sera of patients with Miller Fisher syndrome (MFS) characterised by elevation of the IgG anti-GQ1b antibody. RESULTS: In all, 7 of 12 (58%) consecutive patients with MFS were found to have IgG antibodies to GSCs containing GQ1b, of whom 5 had IgG antibodies to GQ1b-GM1 complex (GQ1b/GM1) and 2 had antibodies to GQ1b/GD1a; 4 of 5 patients without sensory symptoms had anti-GQ1b/GM1 antibodies. CONCLUSIONS: At least three different specificities in MFS-associated antibodies, GQ1b-specific, anti-GQ1b/GM1-positive and anti-GQ1b/GD1a-positive, were observed. In patients with MFS not only GQ1b itself but also clustered epitopes of GSCs, including GQ1b, may be considered to be prime target antigens for serum antibodies. A tendency to escape sensory disturbances is shown by anti-GQ1b/GM1-positive MFS.

Adult↗
PubMed2006

Disinhibition of somatosensory evoked potential recovery in alcoholics.

The pathogenesis of cognitive impairment in alcoholics remains unclear. Previous studies suggested that diffuse white matter atrophy is associated with cognitive impairment in alcoholics. To elucidate this issue, the present study evaluated alcoholics with cognitive impairment using the somatosensory evoked potential (SEP) recovery method, which is suitable for detecting subtle dysfunction at the cortical level. Subjects comprised 12 alcoholics with mild cognitive impairment [Mild group: Mini Mental State Examination Score (MMSE), > or =24; mean, 27.9 +/- 1.6], 12 alcoholics with moderate to severe cognitive impairment (Moderate group: MMSE score, < 24; mean, 21.0 +/- 2.5) and 12 normal subjects (Control group). SEP was recorded from the hand sensory area contralateral to the median nerve stimulated at the wrist. Single-pulse or paired-pulse stimuli at various interstimulus intervals (10-300 ms) were administered. Recovery functions of N9 (a peripheral nerve component), N20, N20-P25 and P25-N33 (cortical components) were studied. N20 recovery curves of both alcoholic groups were less suppressive than those of Controls, and P25-N33 recovery curves of the Moderate group were more excitatory than those of the Mild or Control groups. A disinhibited recovery pattern of N20 indicates subcortical dysfunction, and a disinhibited pattern of P25-N33 would be induced by cortical dysfunction. Therefore, subcortical dysfunction indicated by an abnormal N20 recovery pattern may contribute to the early cognitive impairment of alcoholics, whilst the cortical dysfunction indicated by an abnormal P25-N33 recovery pattern may contribute to the later cognitive impairment of alcoholics.

Alcoholism↗
PubMed2005

Cognitive impairment and diffuse white matter atrophy in alcoholics.

OBJECTIVE: Diffuse brain white matter atrophy is often seen in chronic alcoholics, but its relation with cognitive impairment remains to be solved. In order to address this issue, in alcoholics with cognitive impairment at different levels, we studied relations of the central sensory conduction time (CSCT) or brain magnetic resonance imaging (MRI) findings with the cognitive function. METHODS: Subjects were 35 alcoholics with mild cognitive impairment (mini-mental state examination score, MMSE, >/=24; mean+/-SD, 27.7+/-1.9), 12 with moderate to severe cognitive impairment (MMSE<24; 20.3+/-2.7), 15 with Alzheimer's disease (AD) (MMSE, 18.9+/-4.3) (disease control) and 20 healthy volunteers (MMSE, 28.5+/-1.6) (normal control). Median nerve SEPs were recorded in the all subjects, and the latencies and amplitudes of their N9, N11, P13/14, N20 and P25 components were measured. The ventriculocranial ratio (VCR) and the width of cortical sulci were measured on MRIs. These physiological parameters and MRI findings were compared between the 4 groups of the subject, and correlations between those all features were also analyzed. RESULTS: CSCT and VCR were significantly greater in alcoholics with moderate to severe cognitive impairment than those in the other 3 groups. Pearson's product-moment correlation analyses of the alcoholics disclosed that both the CSCT and VCR had significant negative correlations with the MMSE score. Moreover, the CSCT and VCR were positively correlated. CONCLUSIONS: Both physiological and morphological estimates of the white matter function (CSCT and VCR) had a significant correlation with the cognitive dysfunction. SIGNIFICANCE: The diffuse white matter atrophy may be one of the factors causing cognitive impairment in chronic alcoholics.

Aged↗
PubMed2004

Anti-GQ1b antibody as a factor predictive of mechanical ventilation in Guillain-Barré syndrome.

Compared with 87 unventilated patients with Guillain-Barré syndrome (GBS), 44 ventilated patients with GBS more frequently had multiple cranial nerve involvement (91 vs 50%; p < 0.001) and IgG anti-GQ1b antibody (27 vs 8%; p = 0.006). In GBS patients without ophthalmoparesis, the presence of IgG anti-GQ1b antibody was associated with respiratory failure (12 [3/25] vs 0% [0/67]; p = 0.04). The presence of the antibody may be a factor predictive of respiratory failure in GBS.

Adult↗
PubMed2004

Seasonal variation of multiple sclerosis exacerbations in Japan.

Several reports have described the seasonal variation of multiple sclerosis (MS) attacks in the European countries and in the US. Some have insisted that attacks occurred more frequently in winter or spring. We investigated the possibility of a seasonal variation in the frequency of MS attacks among patients in Japan. A total of 172 MS exacerbations in 34 MS patients were analyzed retrospectively. Attacks were divided into two groups: opticospinal type and brain type. The 12 months of the year were assigned to 6 groups based on average monthly temperature. Of the 172 MS exacerbations, 123 were opticospinal type and 49 were brain type of attacks. The total number of attacks was significantly more frequent in the warmest (July and August) and coldest (January and February) months. The heat of summer in warmer, low latitude areas may be a risk factor for MS attacks.

Adult↗
PubMed2004

Intraspinal sarcoidosis: clinical features, MR imaging and electrophysiological study.

We presented the case of a 58-year-old woman with spinal sarcoidosis at the C4-C6 level. The lesion itself as visualized with magnetic resonance imaging, and its neurological findings responded favorably to treatment with prednisolone. Comparison of pre- and post-treatment values for somatosensory evoked potential (SEP) and central motor conduction time (CMCT) also showed improvement. Analysis of SEP and CMCT can be a useful tool for following up spinal sarcoidosis.

Cervical Vertebrae↗
PubMed2003

GalNAc-GD1a in human peripheral nerve: target sites of anti-ganglioside antibody.

BACKGROUND: The authors previously reported that immunoglobulin G (IgG) antibody to the ganglioside N-acetylgalactosaminyl GD1a (GalNAc-GD1a) is associated with the pure motor variant of Guillain-Barré syndrome (GBS). Elucidation of the localization of GalNAc-GD1a in human peripheral nerve tissue may lead to understanding of the pathogenetic role of anti-GalNAc-GD1a antibody in GBS. METHODS: IgG anti-GalNAc-GD1a-monospecific antibody was purified from anti-GalNAc-GD1a antibody-positive rabbit sera through an affinity column. Anti-neurofilament-200 monoclonal and anti-HNK-1 monoclonal antibodies were used as the markers for axon and myelin. Immunohistochemical study using double fluorescence labeling technique was conducted in human ventral roots (VR), dorsal roots (DR), intramuscular nerves, and sural nerves. Human teased ventral fibers also were studied. RESULTS: Anti-GalNAc-GD1a antibody immunostained an inner part of compact myelin and additionally a periaxonal-axolemma-related portion in the VR, small-diameter DR fibers, and IM nerves. In sural nerves, small fibers were selectively stained. In VR, the staining was localized in the paranodal region. CONCLUSION: Anti-GalNAc-GD1a antibodies in patients' sera may bind to those regions in the VR and IM nerves where GalNAc-GD1a is localized, and may function in the pathogenesis of pure motor type GBS. Further investigation is needed to explain the discrepancy between the immunolocalization of GalNAc-GD1a in sensory nerves and the absence of sensory disturbance in patients with GBS with IgG anti-GalNAc-GD1a antibodies.

Animals↗
PubMed2003

Dysferlin mutations in Japanese Miyoshi myopathy: relationship to phenotype.

OBJECTIVE: To study dysferlin gene mutations and genotype-phenotype correlations in Japanese patients with Miyoshi myopathy (MM). BACKGROUND: MM is an autosomal recessive distal muscular dystrophy that arises from mutations in the dysferlin gene. This gene is also mutated in families with limb girdle muscular dystrophy 2B. METHODS: The authors examined 25 Japanese patients with MM. Genomic DNA was extracted from the peripheral lymphocytes of the patients. The PCR products of each of 55 exons were screened by single strand conformation polymorphism or direct sequencing from the PCR fragments. RESULTS: The authors identified 16 different mutations in 20 patients with MM; 10 were novel. Mutations in Japanese patients are distributed along the entire length of the gene. CONCLUSIONS: Four mutations (C1939G, G3370T, 3746delG, and 4870delT) are relatively more prevalent in this population, accounting for 60% of the mutations in this study. This study revealed that the G3370T mutation was associated with milder forms of MM and the G3510A mutation was associated with a more severe form.

Adult↗
PubMed2002

Primary Sjögren's syndrome initially manifested by optic neuritis: MRI findings.

We herein describe the MRI findings in a patient clinically diagnosed with primary Sjögren's syndrome (SjS) initially manifested by retrobulbar optic neuritis. A 63-year-old woman suddenly had left ocular pain and progressive visual disturbance. MR T2-weighted images revealed hyperintensity in the left optic nerve, with swelling. Contrast-enhanced T1-weighted images showed no abnormal enhancement. Follow-up MRI 6 months after admission revealed no significant changes in the affected optic nerve. To our knowledge, optic neuritis as a complication of SjS has been reported in ten patients [1, 2, 3, 4, 5, 6] and MRI findings in only one of them [6]. We thought MR images were useful for visualizing optic nerve involvement in SjS and observing its course.

Female↗
PubMed2001

Effects of slow repetitive transcranial magnetic stimulation on heart rate variability according to power spectrum analysis.

We examined whether repetitive transcranial magnetic stimulation (rTMS) at a low rate could influence autonomic function, specially heart rate variability (HRV) by power spectrum analysis. We studied 16 healthy male volunteers as a stimulation group and 16 others as a sham group. The stimulation group received magnetic stimulations from a circular coil over Cz at a frequency of 0.2 Hz and an intensity presenting 90% of the motor threshold. Experiments in both groups included four daily sessions; at each, a train of 70 stimuli was delivered over 350 s. HRV of low-frequency power (LF) in a standing position and high-frequency power (HF) in a supine position were measured before and after each session. After stimulation, HF and LF powers were significantly increased. After sham stimulation, the power of HF but not that of LF significantly increased. Neither actual nor sham stimulation produced a long-term effect detectable on day 5. The finding of transiently increased LF power following actual but not sham stimulation suggests that rTMS may activate the sympathetic nervous system.

Adult↗
PubMed2001

Guillain-Barré syndrome with IgM antibody to the ganglioside GalNAc-GD1a.

We analyzed the characteristics of 29 Guillain-Barré syndrome (GBS) patients with IgM anti-GalNAc-GD1a antibodies. Fourteen of them had had an antecedent cytomegalovirus infection (CMV group) and 12 gastrointestinal infection (G-I group). Most of the G-I group patients (nine of 12) were subsequent to Campylobacter jejuni infection. Electrophysiological results in both groups patients predominantly indicated demyelinating neuropathy. The CMV group patients were characterized by slow progression and frequent facial and sensory deficits. IgM antibodies in their sera recognized an epitope shared by GalNAc-GD1a and GM2. The G-I group patients frequently showed motor type of GBS with cranial nerves spared. IgM antibodies specific to GalNAc-GD1a were present in their sera.

Adult↗
PubMed2001

Expression of dystroglycan complex in satellite cells of dorsal root ganglia.

In Schwann cells, the transmembrane glycoprotein beta-dystroglycan composes the dystroglycan complex together with the extracellular glycoprotein alpha-dystroglycan, which binds laminin-2 (alpha2/beta1/gamma1), a major component of the Schwann cell basal lamina. In the Schwann cell cytoplasm, beta-dystroglycan is anchored to a dystrophin isoform, Dp116. In this study, we investigated the expression of beta-dystroglycan, Dp116 and the laminin-alpha2 chain in satellite cells of rat dorsal root ganglia (DRGs). Immunohistochemical study showed that immunoreactivities for beta-dystroglycan and Dp116 were both localized to the outer rim of neuron-satellite cell and axon-Schwann cell units, indicating that both satellite and Schwann cells expressed these proteins in DRGs. Immunoreactivity for the laminin-alpha2 chain was detected in a similar location, indicating that the basal lamina surrounding satellite and Schwann cells in DRGs contained laminin-2. Ultrastructurally, immunoreactivity for the cytoplasmic domain of beta-dystroglycan as well as that for Dp116 was most intense in the cytoplasm just underlying the outer membrane of satellite cells. The immunoreactivity for laminin was associated with the outer surface of those cells, suggesting that it was localized in the surrounding basal lamina. These results indicate that the dystroglycan complex is expressed in the satellite cell outer membrane and involved in the adhesion with the basal lamina through the interaction with laminin-2.

Animals↗
PubMed2001

Somatosensory evoked potential recovery in myotonic dystrophy.

OBJECTIVE: To evaluate recovery functions of the sensory cortex using somatosensory evoked potentials (SEPs) elicited by paired stimuli of the median nerve in patients with myotonic dystrophy (MD). SUBJECTS/METHODS: Twelve MD patients were enrolled in the present investigation. Five patients with facioscapulohumeral muscular dystrophy (FSH) and 12 healthy volunteers were studied as control groups. SEP was recorded from the hand sensory area contralateral to the median nerve stimulated at the wrist. Single pulse or paired-pulse stimuli at various interstimulus intervals (ISIs) (10, 20, 40, 60, 80, 100, 150, 200 and 300 ms) were given. Recovery functions of N9, N20onset-N20peak, N20-P25 and P25-N33 components were studied. RESULTS: Conventional SEPs to a single stimulus were normal in the latency and amplitude in all the patients. Recovery functions of both N9 and N20o-N20p components were normal in the patients. In contrast, in MD patients, disinhibited or hyperexcitable recovery pattern was observed in recovery curves of the N20-P25 or P25-N33 components, whereas those were normal in FSH patients. CONCLUSIONS: Disinhibited cortical excitability (or hyperexcitability) is present in the sensory cortex in patients with myotonic dystrophy. This may reflect cortical pathology or functional alteration of the sensory cortex in MD.

Adult↗
PubMed2001

Hemophagocytic syndrome and adult Still's disease associated with meningoencephalitis and unconsciousness.

We describe a 19-year-old woman with hemophagocytic syndrome and adult Still's disease who showed rare features of central neurological involvement, including cerebellar symptoms and the sudden onset of unconsciousness with pleocytosis in the cerebrospinal fluid during the early course of the illness. As this patient's serum showed a high level of interferon-gamma and soluble interleukin 2 receptor, this might play a pathologic role in the development of central nervous system symptoms. Intensive treatment consisting of methylprednisolone pulse therapy followed by the oral administration of methylprednisolone and cyclosporine, as well as plasma exchange, was found to achieve good results.

Adult↗
PubMed2001

Nodular cutaneous amyloidosis and carpal tunnel syndrome due to the amyloidogenic transthyretin His 114 variant.

This is the second report of transthyretin (TTR) amyloidosis in a patient who had ATTR Tyr114His diagnosed by mass spectrometry and gene analysis. This case had some clinical features that differed from those of the first reported cases. The patient, 73-year-old man, complained of generalized cutaneous tubercula that had started at age 68. These tubercula gradually increased in size and became generalized. He felt a slight numbness in his extremities. Clinical and electrophysiological examinations revealed that he had bilateral carpal tunnel syndrome (CTS), whereas there was no clear evidence of sensory and/or motor polyneuropathy. Autonomic symptoms were not present. Biopsy studies revealed that both his tuberculum and his sural nerve contained TTR-related amyloid. In his sural nerve, amyloid deposits were observed mainly in the perineurium, not in the endoneurium, and there was no significant depletion of myelinated fibers. The features of this patient were clinically characterized by generalized cutaneous amyloid deposits and late-onset CTS with a lack of overt polyneuropathy and autonomic dysfunction. The unique clinical features in this case seemed to be consistent with the distribution of amyloid deposits.

Aged↗