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Biomedical subjects

G Sobue

Publications and source records attributed to G Sobue.

At least 199 records · Page 11Linked to original sources
PubMed1996

Morphologic features of the normal human cadaveric spinal cord.

STUDY DESIGN: The cross-sectional area and diameter of the normal cadaveric spinal cord at each segmental level were measured, and the morphologic features were presented. OBJECTIVES: To provide accurate anatomic descriptions and morphometric data of the human spinal cord. SUMMARY OF BACKGROUND DATA: There is a large individual variation in human spinal cord size, and no authorized standard of measurement has been established. There have been few detailed descriptions of the normal morphologic features of the spinal cord. METHODS: The authors measured the cross-sectional area and diameter of the spinal cord at each segment from C2 and S3 in 12 cadaveric specimens, and the morphologic features of each segment were described. RESULTS: The relative ratio of the cross-sectional area of each segment to that of the C3 segment was similar in all the specimens examined despite a large individual variation in absolute cord size. Each segment had distinct qualitative and quantitative morphologic features. CONCLUSIONS: The normal cross-sectional area of the spinal cord at any segment in an individual is calculable from measurements of a given single normal segment. This value appears to be an appropriate and practical standard of measurement of the normal morphologic features of the spinal cord.

Adult↗
PubMed1996

Toxic effects of hexane derivatives on cultured rat Schwann cells.

The cytotoxic effects of the following five hexane-related compounds were examined on Schwann cell DNA synthesis: 2,5-hexanedione (2,5-HD), 2-hexanol (2-OH), 2-hexanone (MnBK), 2,5-dimethylfuran (DF) and gamma-valerolactone (VL). Schwann cells were isolated from the sciatic nerves of neonatal Sprague-Dawley rats and cultured. [(3)H]-thymidine incorporation into Schwann cell nuclei was measured by scintillation spectrometry and autoradiography when hexane derivatives were added to the culture medium. All of the hexane-related compounds suppressed [(3)H]-thymidine incorporation in a concentration-dependent manner. DF was the most cytotoxic for the inhibition of Schwann cell DNA synthesis among the compounds. The finding suggests that DF-mediated cytotoxicity should be taken into account as a possible additional mechanism of hexane intoxication, especially in the impairment of mitotic cells.

Animals↗
PubMed1996

Expression of glial cell line-derived growth factor mRNA in the spinal cord and muscle in amyotrophic lateral sclerosis.

The steady-state expression levels of glial cell line-derived growth factor (GDNF) mRNA was studied in the post mortem spinal cord and muscle of patients with amyotrophic lateral sclerosis (ALS), by reverse transcription followed by polymerase chain reaction (RT-PCR). GDNF mRNA levels in the lumbar cord were significantly increased in ALS as compared with controls. On the other hand, GDNF mRNA levels were significantly lower in the muscle in ALS patients. The increase of GDNF mRNA in the spinal cord mostly reflected an increase in the anterior horn, anterior and lateral columns, where the pathological involvement was severe. In the posterior column and posterior horn with less pathological involvement, the increase was less. These results suggest that GDNF mRNA levels are inversely regulated between the spinal cord and muscle in ALS, increased in the spinal cord and lowered in the muscle, in correlation with the pathological severity.

Aged↗
PubMed1996

Possible mechanism of anhidrosis in a symptomatic female carrier of Fabry's disease: an assessment by skin sympathetic nerve activity and sympathetic skin response.

Fabry's disease, X-linked alpha-galactosidase deficiency, features a variety of autonomic abnormalities including anhidrosis. In this study, we measured the skin sympathetic nerve activity (SSNA), skin potential and sweat rate in a symptomatic female carrier to investigate the underlying pathophysiology of anhidrosis. The basal activity and responsiveness of SSNA were both fairly well preserved, although slightly reduced compared with the control levels. However, sweating was completely absent, despite the normal skin potential change in response to SSNA bursts. These results suggest that anhidrosis in Fabry's disease is a result of sweat gland dysfunction as well as abnormal SSNA.

Adult↗
PubMed1996

Expression of mRNAs for neurotrophic factors (NGF, BDNF, NT-3, and GDNF) and their receptors (p75NGFR, trkA, trkB, and trkC) in the adult human peripheral nervous system and nonneural tissues.

The steady-state mRNA levels of the four neurotrophic factors of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and glial cell line-derived neurotrophic factor (GDNF) and their receptors (p75NGFR, trkA, trkB and trkC) in the adult human peripheral nervous system (PNS) as well as nonneural tissues were examined using quantitative reverse transcription-polymerase chain reaction (RT-PCR). NGF and BDNF mRNA levels were high in the heart and spleen as well as in the dorsal root ganglia (DRG) and spinal cord, showing similar spatial expression patterns, while NT-3 mRNA levels were more pronounced in the liver and spleen. In contrast to these neurotrophins, GDNF mRNA expression occurred at the highest levels in the muscle, and it was also comparatively high in the spinal cord. p75NGFR mRNA was expressed extensively throughout the PNS tissues and in the spleen. The spatial expression patterns differed among trkA, and trkB and trkC mRNAs. trkA mRNA was greatly expressed in the DRG, sympathetic ganglia and spleen, while the trkB and trkC mRNA levels were high in the DRG, spinal cord and brain. The levels of trkB and trkC mRNAs with tyrosine kinase domain, compared to those with extracellular domain, were relatively high in the DRG, whereas they were low in the spinal cord and brain. The spatial patterns of the distributions of neurotrophic factors and their receptors mRNA levels in the adult human PNS and nonneural tissues are largely similar to those reported in other mammals, but these findings provide further, more specific, understanding relevant to the therapeutic approach to human diseases.

Adult↗
PubMed1996

Age-related changes in human spinal ventral horn cells with special reference to the loss of small neurons in the intermediate zone: a quantitative analysis.

A cytoarchitectonic study of spinal ventral horn cells was performed to identify age-related changes. The diameter distribution of ventral horn neurons of the fourth lumbar segment of the spinal cord and their size and topographical distributions were investigated in 14 autopsy cases. These cases represented patients of 18-100 years of age who had died of non-neurological diseases. The results indicate that small neurons widely distributed in the intermediate zone of the ventral horn significantly diminished with aging (P < 0.0005, r = -0.898), whereas medium-sized and large neurons located in the medial and lateral nuclei showed only a slight decrease with advancing age. The total number of neurons in the whole ventral horn was also noted to decrease significantly with aging (P < 0.0005, r = -0.899). While small neurons in the intermediate zone of the ventral horn are thought to be mostly interneurons, their physiological function still remains obscure in many respects. The findings of this study provide insight into age-related cell loss in terms of size and location.

Adolescent↗
PubMed1996

Differential pattern in tissue-specific somatic mosaicism of expanded CAG trinucleotide repeats in dentatorubral-pallidoluysian atrophy, Machado-Joseph disease, and X-linked recessive spinal and bulbar muscular atrophy.

We investigated the somatic mosaicism of trinucleotide repeat expansion in the neural and nonneural tissues of a dentatorubral-pallidoluysian atrophy (DRPLA), Machado-Joseph disease (MJD), and spinal and bulbar muscular atrophy (SBMA) patient and their correlation to the topographical distribution of the pathological involvement. The spatial pattern of tissue-specific somatic mosaicism in the CAG repeat size was significantly different among the DRPLA, MJD and SBMA patients. The size of the major bands of the mutant CAG repeat allele was significantly smaller in the cerebellar cortex in both DRPLA and MJD patients by 6 and 2 repeat units respectively and larger in the colon and liver of DRPLA by 5 repeats or more. There were also 1-2 repeat-sized small variations of major band size among the neural tissues in DRPLA. In contrast, there was no tissue-specific variation of major bands of CAG repeats and diversity of extra bands among the examined tissues including the cerebellum in the SBMA patient. There was no parallel occurrence of tissue-specific CAG instability and severity of neuropathological involvement in the neural and nonneural tissues of DRPLA, MJD and SBMA patients. Lack of significant tissue-specific somatic mosaicism in SBMA including the cerebellar cortex may suggest that CAG repeat expansion in the mutant androgen receptor gene is far more stable compared with that in DRPLA and MJD as well as those reported in Huntington's disease.

Adult↗
PubMed1996

Demonstration of slow acetylator genotype of N-acetyltransferase in isoniazid neuropathy using an archival hematoxylin and eosin section of a sural nerve biopsy specimen.

The genotype for N-acetyltransferase was analyzed in five Japanese patients with isoniazid neuropathy by using the allele specific polymerase chain reaction for a single slice of the 30-year-old paraffin-embedded and hematoxylin-eosin stained sural nerve biopsy specimens. We found slow acetylator genotypes for N-acetyltransferase in all isoniazid neuropathy patients. This result confirmed that patients with the slow acetylator genotype tend to develop neuropathy after administration of isoniazid.

Acetylation↗
PubMed1996

Epidemiology of bacterial meningitis in children: Aichi Prefecture, Japan, 1984-1993.

The details of 328 patients with bacterial meningitis, admitted from 1984 through 1993, were obtained from 46 departments of pediatrics of large hospitals through questionnaires. The incidence rate per 100,000 child-years was 2.32, being higher in children aged 0-4 years (rate, 7.22) than 5-15 years (rate, 0.49). The disease in the 274 (84%) etiologically diagnosed patients was due to Haemophilus influenzae (95), Streptococcus pneumoniae (56), Group B streptococci (GBS) (41), Escherichia coli (27), and other agents (55), including 7 patients with Mycobacterium tuberculosis infection. The short-term outcome (mean length of follow-up, 2 years, 11 months) of meningitis was death in 26 patients (8.2%) and sequelae in 49 (16.0%), including 26 children with multiple residual impairment. Tuberculous, pneumococcal, and GBS meningitis with a poor outcome increased during the late period (1989-1993) of the 10-year study. The annual infant mortality rate for purulent meningitis decreased from 3.7 to 1.4 per 100,000 population between 1984 and 1993. The incidence of a poor outcome (death and sequelae) in newborns decreased by half during the late period.

Adolescent↗
PubMed1996

Founder effect in spinal and bulbar muscular atrophy (SBMA).

We analyzed the polymorphic (CAG)n and (GGC)n repeats of the androgen receptor gene in 113 unrelated X-linked spinal and bulbar muscular atrophy (SBMA) X chromosomes and 173 control X chromosomes in Japanese males. The control chromosomes had an average CAG repeat number of 21 +/- 3 with a range from 14-32 repeat units, and SBMA chromosomes had a range from 40-55 with a median of 47 +/- 3 copies. The control chromosomes had seven different alleles of the (GGC)n repeat with the range of 11 to 17; the most frequent size of (GGC)n was 16 (79%), while (GGC)17 was very rare (1%). However, in SBMA chromosomes only two alleles were seen; the most frequent size of (GGC)n was 16 (61%) followed by 17 (39%). (GGC)n size distribution was significantly different between SBMA and control chromosomes (P < 0.0001), indicating the presence of linkage disequilibrium. There was no allelic association between the (CAG)n and (GGC)n microsatellites among control subjects as well as SBMA patients, which suggests that a founder effect makes a more significant contribution to generation of Japanese SBMA chromosomes than new mutations.

Genetic Linkage↗
PubMed1996

Progressive systemic sclerosis associated with multiple mononeuropathy.

BACKGROUND: Progressive systemic sclerosis (PSS) is a chronic connective tissue inflammatory disease which commonly attacks the skin and the visceral organs, but rarely the peripheral nervous system. OBJECTIVE: The aim of this study was to investigate PSS accompanied by peripheral neuropathy clinically, electrophysiologically and pathologically from a sural nerve biopsy. METHODS: Two women suffering from PSS but without any other collagen disease were studied. Both patients developed peripheral neuropathy with multiple mononeuropathy of the limbs, and in one woman, in the trunk as well. RESULTS: A biopsy of the sural nerve revealed axonal and myelin segmental degeneration, loss of large myelinated fibers and an increase of collagen fibers, but there was no evidence of vasculitis. An electron microscopic examination revealed degenerated axons, disrupted myelin sheaths and multilayered basal lamina in the capillaries. CONCLUSION: Mononeuropathy in PSS suggests that ischemic neuropathy may be related to the immune-mediated vasculopathy.

Aged↗
PubMed1996

Infarction of superior cerebellar artery presenting as cerebellar symptoms.

BACKGROUND: MRI of the brain has facilitated the diagnosis of cerebellar infarction in the territory of the superior cerebellar artery (SCA). We analyzed the data on patients with SCA infarction who presented with only cerebellar symptoms in an attempt to define its underlying pathophysiology. SUMMARY OF REPORT: Ten patients with SCA infarction who presented with cerebellar symptoms were studied by brain MRI, angiography, and underlying pathology. Brain MRI demonstrated an infarct in the SCA territory in the anterior rostral cerebellum of all patients. None had abnormalities in the brain stem. In four patients, a hemorrhagic infarct was present in the same region. Cerebral angiography revealed no obvious SCA occlusion or atherosclerotic vascular disease in any patient. Eight of the 10 patients had heart disease, such as atrial fibrillation or old myocardial infarction. The presumed diagnosis was occlusion of the SCA in its periphery due to cardiogenic embolism. CONCLUSIONS: When a patient presents with only cerebellar symptoms and has cerebellar infarction demonstrated by brain MRI, the SCA branch is probably occluded by cardiogenic embolism.

Aged↗
PubMed1996

Selective loss of small myelinated fibers in the lateral corticospinal tract due to midbrain infarction.

Small myelinated fibers in the lateral corticospinal tract (LCST) were selectively diminished as compared with large myelinated fibers in a patient with an old paramedian midbrain infarct involving the red nuclei, oculomotor nuclei, and inferior olivary pseudohypertrophy. Although the physiologic function of small myelinated fibers in the LCST is unknown in humans, we hypothesize that some of these fibers may include the rubrospinal tract.

Cerebral Infarction↗
PubMed1996

[Peptidergic sweating in multiple system atrophy and hereditary spinocerebellar ataxia with special reference to calcitonin gene-related peptide].

Calcitonin gene-related peptide (CGRP)-like immunoreactivity has been demonstrated to be present in nerve terminals around the sweat glands. We have previously demonstrated that CGRP modulates the cholinergic sweating activity. The present study was designed to evaluate the locally administrated CGRP on sweating of patients with multiple system atrophy (MSA) and hereditary spinocerebellar ataxia (HSCA) consisting of 10 males and 11 females. Among 9 HSCA, 3 was diagnosed as Machado-Joseph disease by clinical and DNA diagnostic assessment. CGRP and methacholine chloride (MCH) was dissolved in saline solution to specified concentration, and 0.1ml of which was injected intradermally at the center of a forearm test area. The sweat rate was recorded continuously by the capacitance hygrometry in a relatively cool environment in which the spontaneous sweating was absent. CGRP significantly increased the sweat rate when it was administrated with MCH on normal subjects. There was a clear dose-dependent relationship between the dose of CGRP and its enhancement. This enhancement was significantly reduced in patients with MSA as compared with controls. On the other hand, most of HSCA showed no remarkable impairment of CGRP enhancement. These results suggest that peptidergic sweating is extensively affected in patients with MSA but is not in patients with HSCA, which may be the consequence of peptidergic sweating dysfunction in MSA.

Adult↗
PubMed1996

[Fas antigen is expressed in human diseased muscles, but does not link to apoptosis].

In an attempt to determine whether the Fas-Fas-ligand mediated apoptosis occurs in the pathologic process of human myopathies, we examined the expression of Fas antigen, Fas-ligand mRNA, and chromosomal DNA fragmentation in the muscle cells of several human muscle disorders. The Fas antigen of a whole molecule was expressed on the muscle fibers of patients with muscle wasting diseases. However, there was no evidence of an apoptotic process, nor Fas-ligand synthesis in the diseased muscle tissue. Therefore, the expression of Fas antigen on muscle fibers in diseased muscle might be related to unknown biological functions other than "apoptosis" in the process of muscle fiber injury.

Apoptosis↗
PubMed1996

[A case of hereditary neuropathy with liability to pressure palsies (HNPP) with diabetes mellitus].

Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal dominant neuropathy recently reported to be associated with deletion of the peripheral myelin protein-22 (PMP-22) gene. We report a 39-year-old man with recurrent brachial plexopathy and foot drop complicated by uncontrolled diabetes mellitus (DM). Right foot drop occurred at 31 years of the age and the patient subsequently experienced difficulty in raising his right arm. Neurological examination revealed weakness of the right deltoid, biceps muscles and tibialis anterior muscles. Deep tendon reflexes were generally absent. Sensory nerve conduction velocities in th ulnar, median and sural nerves were prolonged. Serum glucose and HB Alc levels were elevated to 468 mg/dl and 12.5%, respectively. Initially, it was difficult to diagnose the neuropathy as HNPP because the patient had poorly controlled diabetes mellitus and was unaware of similar disease in his family. In addition, focal asymmetric motor neuropathy and good recovery can develop in diabetes mellitus, occasionally with recurrence. We were able to make a final diagnosis of HNPP by detecting deletion of the PMP-22 gene region. After the diagnosis was confirmed, we examined the patient's family and found that his father experienced recurrent episodes of bilateral foot drop. This case suggests that gene analysis is sometimes essential in the differential diagnosis of hereditary peripheral neuropathies.

Adult↗