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Biomedical subjects

G Sobue

Publications and source records attributed to G Sobue.

At least 307 records · Page 17Linked to original sources

[Clinical features of the peripheral nerve involvement in necrotizing angitis--characteristics in polyarteritis nodosa and allergic granulomatous angitis].

Thirteen patients with peripheral neuropathy caused by necrotizing vasculitis were clinico-pathologically analyzed. These patients consisted of nine classical periarteritis nodosa (PN), four allergic granulomatous angitis (Churg-Strauss syndrome, AGA). All of them were proven to have a necrotizing vasculitis by sural nerve biopsy. The characteristics of peripheral neuropathy of these patients were summarized as follows. 1) Mononeuritis multiplex was a principal features in all patients preferentially localized in common peroneal, sural, radial median and ulnar nerves, with all modality of sensory impairment. 2) Radiation or diffuse deep-pain was a major initial symptom. Since this pain occurs frequently in the manner of sudden onset, the patient can tell the day of onset. 3) Local edema on the skin of involved region was initially observed. 4) Muscular atrophy and weakness was distributed more widely than sensory impairment. 5) Morphometric and teased-fiber study of biopsied sural nerves revealed axonal degeneration as a major pathological process. As compared to myelinated fibers, unmyelinated fibers were likely to be well preserved in morphology and population, which suggests that unmyelinated fibers are relatively resistant to ischemia. 6) Motor and sensory conduction study showed greatly decreased sensory and motor action potentials frequently resulting in absent of recordings. Conduction velocity is almost within normal range or just below the normal. Routine EMG recordings showed active denervation potentials in the involved muscles. 7) Protein in CSF was rarely elevated which suggested involvement of the spinal roots is infrequent. 8) Hypereosinophilia, thrombocythemia, fever, increased erythrocyte sedimentation rate, positive CRP and RA, and polyclonal hypergammaglobulinemia (IgG, IgA) were observed in most cases.

Adult↗

[Pathology of the peripheral nervous system in polyarteritis nodosa: a clinico-pathological study of two autopsy cases].

Peripheral nerves from the two autopsied cases with polyarteritis nodosa were pathologically examined. Case 1 was a seventy-year-old female, complaining of numbness and weakness of the extremities. Sensory deficits in all modality with induced dysesthesia were distributed as a mode of overlapping mononeuritis multiplex in the distal portion of extremities. Motor involvement was also noted in extremities in disarray-accentuated pattern. Extensive steroid hormone therapy was performed and remarkable improvement in clinical sign was temporarily obtained. Relapse with bowel involvement was a cause of the death. In the post-mortem examination, central fascicular degeneration with the loss of large myelinated fibers were seen at the middle portion of upper limbs in median nerve and at the lower mid-thigh in sciatic nerve. In the distal portion of those nerves, diffuse extensive loss of large myelinated fibers in the fasciculus were observed. Some of small thin myelinated fibers in the central fasciculus or distal portion of nerves were thought to be regenerated in nature. Accumulation of cell organelles in the axonal swellings were frequently occurred in the proximal to the ischemic site. Case 2 was a seventy five-year-old female with a both motor and sensory involvement in the distal extremities. Right pulmonary effusion and extensive subcutaneous hemorrhage and necrotic gangrene in the leg was also noted. Post-mortem examination of peripheral nerves revealed a presence of central fascicular degeneration in the distal sciatic nerves and nearly complete loss of myelinated fibers in the distal nerves. Ventral and dorsal roots and dorsal root ganglia were well preserved.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

[Chronic recurrent-progressive polyradiculoneuritis--Characteristics of autonomic dysfunction].

We examined autonomic dysfunctions in 12 patients with chronic-recurrent-progressive polyradiculoneuritis (C-R-P-PRN), consisting of 6 males and 6 females with the clinical duration of 8 months to 16 years, and with the age ranged 13 and 71 years. Sixteen healthy volunteers, aged 20 to 70 years, were also examined. Thermal sweat rate was recorded on the palm, forearm, upper arm, anterior chest, lateral thigh and lateral aspect of lower leg using a ventilated capsular method in a climatic chamber at 40 degrees C and 40% of relative humidity. After steady state was attained, thermal sweat rate was measured. Local sweating induced by intradermal injection of pilocarpine and nicotine (a concentration of 10(-4), 0.1 ml) was also measured on the forearm and lower lateral leg at 23 degrees C of room temperature and 40% of relative humidity. Other autonomic functions including skin temperature at rest and after cold loading (15 degrees C, 6 minutes), variation in the R-R interval (CV%), pupillary function (response to 1.25% epinephrine, 2(-5) pilocarpine, 5% tyramine), orthostatic hypotension and bladder dysfunction were also monitored. A decrease in sweat rate and recovery rate of skin temperature was seen more frequently in patients with C-R-P-PRN than normal volunteers. Abnormality in the thermal sweat rate and local sweat response against nicotine and pilocarpine was present more frequently in the forearm and distal leg as compared with the chest and thigh.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Loss of spinal anterior horn cells in X-linked recessive bulbospinal muscular atrophy--a morphometric study of lower motoneuron loss].

A morphometric analysis was performed to study three-dimensional distribution of the anterior horn cells in the L1 segmens from four cases of X-linked bulbospinal muscular atrophy (X-BSMA) and three age-matched controls. At autopsy, the L4 spinal segment was removed and fixed in 4% paraformaldehyde in PBS at pH 7.4, then embedded in paraffin. Serial sections of 10 microns in thickness from the rostral end of L4 segment were obtained. Every tenth section was stained with Klüver-Barrera method. The anterior spinal horn in this study was designated as the gray matter anterior to the line from the central spinal canal perpendicular to the ventral spinal fissure. The diameter of the remaining neurons with obvious nucleolus in the anterior horn was measured with TGZ-3 particle size analyzer (Zeiss) on the 205 time-magnified picture, and their location was schematically plotted on a montage of the ventral horn. Neuronal loss was more marked in X-BSMA than in amyotrophic lateral sclerosis (ALS) and Shy-Drager syndrome (SDS). In X-BSMA, the loss was most prominent in cells with large-size, and in those located in the lateral and medial vental nuclei (lamina IX after Rexed's classification). Small or intermediate cells located in the area of inner-medial portion of the ventral horn (lamina VII & VIII after Rexed's classification) were also significantly depleted. In some cases, the loss of small neuron was more marked than SDS.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

[Postganglionic sudomotor function in multiple system atrophy].

Postganglionic sudomotor function were examined on 12 patients with multiple system atrophy (MSA) consisting of 5 males and 7 females with the clinical duration of 1 to 10 years, and with the age ranged 51 and 70 years. Sixteen healthy volunteers, aged 38 to 75 years were also examined as the control. Local sweating induced by intradermal injection of pilocarpine and nicotine (a concentration of 10(-4) g/ml) was quantitatively measured on the volar surface of the forearm and lower lateral leg using a ventilated capsule method in a climatic chamber at 23 degrees C and 40% of relative humidity. Maximal sweat rate induced by nicotine and pilocarpine was significantly reduced in patients with MSA as compared with controls in both the forearm and lower lateral leg. MSA cases associated with more prominent autonomic dysfunction as well as hyposweating, showed a more remarkable impairment of local sweat responses. Particularly, in 6 cases with Shy-Drager syndrome, there was no sweat response by the injection of both pilocarpine and nicotine. The study of an autopsied case with Shy-Drager syndrome revealed neurons in the para-vertebral sympathetic ganglia were well populated, though neurons in the lateral horns of the lower thoracic spinal cord were almost completely depleted. This substantial discrepancy between the impaired sudomotor function and morphological findings may imply several hypothetical views on the mode of pathology of postganglionic sudomotor nerves. The present results, however, strongly suggested that postganglionic sudomotor functions are more extensively involved in patients with MSA than had ever been believed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Gangliosides modulate Schwann cell proliferation and morphology.

We examined the effect of gangliosides on Schwann cell cultures isolated from neonatal rat sciatic nerves. Addition of gangliosides (GM1, GM3, and ganglioside mixture) at concentrations between 0.25 and 2 mg/ml significantly diminished both the baseline rate of proliferation of the Schwann cells and their response to two types of mitogens, the axolemmal fragments and derivatives of adenosine 3'-5'-monophosphate (cAMP). Gangliosides, the sialic acid residue of which had been removed, were highly toxic to the Schwann cells, which went to indicate that sialic acid is necessary to produce the inhibitory effects. Gangliosides also produced prominent changes in the morphological appearance of the Schwann cells. Most of the Schwann cells treated with gangliosides had an elongated shape with long processes and an alignment of end-to-end or side-by-side cell adhesion. These effects of gangliosides apparently were not mediated by cAMP, since intracellular cyclic adenosine monophosphate (cAMP) of Schwann cells at a basal- and forskolin-stimulated level was not altered by the exogenous gangliosides. These findings indicate that the direct effect of gangliosides on Schwann cells should also be considered as a background mechanism of ganglioside-induced facilitation of neuronal regeneration.

Animals↗

Expression of nerve growth factor receptor in human peripheral neuropathies.

Nerve growth factor (NGF) receptors in human sural nerve biopsies were detected immunohistochemically using a monoclonal anti-human NGF receptor antibody. NGF receptors were not visualized within the endoneurium of normal adult nerves but were readily demonstrable within the endoneurium of nerves undergoing active axonal degeneration. Immunostaining of adjacent sections for S-100 beta protein, a specific Schwann cell marker, suggested that Schwann cells expressed the NGF receptors induced by axonal degeneration. Residual Schwann cells in nerves in which axons were completely depleted also expressed NGF receptors. NGF receptors were not detected in relation to thinly myelinated regenerating axons, nor were they detected in the endoneurium of nerves that had undergone segmental demyelination and remyelination. The increased expression of NGF receptors in human axonal neuropathies may contribute to regeneration by NGF-responsive neurons in these disorders.

Adult↗

Acquired idiopathic generalized anhidrosis: a distinctive clinical syndrome.

The present study concerns a 28-year-old Japanese man with acquired generalized anhidrosis. The patient's ability to perspire was investigated in an artificial climate room maintained at 40 degrees C and 40% humidity. Although the body temperature rose to 38 degrees C, the patient did not sweat. Neither did sweating occur when the patient was given an intradermal injection of pilocarpine or nicotine. The serum IgE level was elevated. Atrophy and degeneration of the sweat glands, as well as infiltration by lymphocytes and mast cells around the sweat glands, were observed in skin biopsies. Anhidrosis in this patient was suggested to be the result of reduced function of the sweat glands themselves with possible underlying immune-mediated basis.

Adult↗

Peptidergic and adrenergic regulation of the intracellular 3',5'-cyclic adenosine monophosphate content in cultured rat Schwann cells.

We investigated the role of neuropeptides and adrenergic agonists in the regulation of intracellular 3',5'-cyclic adenosine monophosphate (cyclic AMP) contents in cultured Schwann cells from sciatic nerve of neonatal Sprague-Dawley rats. Of the neuropeptides examined, vasoactive intestinal polypeptide (VIP) and secretin markedly stimulated the accumulation of intracellular cyclic AMP in a time- and dose-dependent manner with half maximum at 3 and 12 min, and 2.8 X 10(-5) and 5.0 X 10(-5) M, respectively. While somatostatin, substance P, adrenocorticotropin (ACTH), beta-endorphin, and nerve growth factor (NGF) did not show any effect on cyclic AMP metabolism, isoproterenol (IP), norepinephrine (NE) and epinephrine (E) also markedly elevated the Schwann cell cyclic AMP concentration. The rank-order of potency of these adrenergic catecholamines on cyclic AMP accumulation was isoproterenol greater than norepinephrine greater than epinephrine. Simultaneous addition of VIP or secretin to the Schwann cell culture synergistically enhanced the norepinephrine-induced elevation of intracellular cyclic AMP. The effect of norepinephrine was antagonized by a selective beta 1-adrenergic antagonist but not by beta 2- nor alpha-adrenergic antagonists. These results suggest that VIP, secretin, and beta 1-adrenergic agonists alone or synergistically may play a part in the regulation of metabolism of Schwann cells mediated through a cyclic AMP-dependent mechanism.

Animals↗

A cyclic AMP analogue induces synthesis of a myelin-specific glycoprotein by cultured Schwann cells.

Neonatal rat Schwann cells, cultured with agents which increase intracellular cyclic AMP, were prompted to resume synthesis of a 170,000 Mr glycoprotein which is specific to peripheral nervous system myelin and is herein referred to as P170K. We have shown previously that similar treatment induces the synthesis by Schwann cells of the myelin lipid, galactocerebroside. In contrast to P170K and galactocerebroside, syntheses of P0 and myelin basic protein were not induced. Intracellular cyclic AMP is thus likely to be a participant in the complex system regulating myelination.

8-Bromo Cyclic Adenosine Monophosphate↗

Chronic progressive sensory ataxic neuropathy with polyclonal gammopathy and disseminated focal perivascular cellular infiltrations.

One autopsied case of chronic progressive sensory-ataxic neuropathy with polyclonal elevation of serum and CSF IgG and IgA and without malignancy is reported. A marked loss of large myelinated fibers was universal in both the central and peripheral rami of primary sensory neurons. Fiber loss showed a multifocal patchy pattern in the proximal nerve trunks. The posterior root ganglion cell bodies were moderately atrophic and loss of large cells was observed. Unmyelinated axons were well preserved. The ventral spinal roots, ventral spinal horn cells, and muscles showed minimal involvement. There were focal perivascular mononuclear inflammatory cells without necrotizing vasculitis around the endoneurial and epineurial vessels. Similar perivascular cellular invasions were observed in the visceral organs, occasionally forming germinal follicle centers. This case suggested that this neuropathy has a unique background with a possible immune-mediated basis.

Ataxia↗

Cultured rat Schwann cells express low affinity receptors for nerve growth factor.

Schwann cell cultures prepared from postnatal Sprague-Dawley rat sciatic nerves were used to demonstrate the presence of specific receptors for the beta-subunit of nerve growth factor (NGF) on rat Schwann cells. Indirect immunofluorescence microscopy with a monoclonal antineuronal NGF receptor (NGFR) antibody indicated that NGFR antigen was expressed on the surface of Schwann cells but not of endoneurial fibroblasts. Studies with 125I-NGF confirmed this distribution of NGFR in the cultures and showed that the Schwann cell NGFR had a single NGF binding affinity (Kd of 1.8 x 10(-9) M). 125I-NGF binding by the cultured Schwann cells increased with time in vitro, reaching a plateau level on the 4th day, but decreased with increasing age, reaching 40% of the neonatal value in Schwann cells isolated from 12-day-old rats. Treatment of the cultures with NGF did not alter Schwann cell phenotype, survival or proliferation.

Animals↗

A monoclonal antibody to Schwann cell surface membrane recognizes a cAMP inducible epitope.

A monoclonal antibody to the surface membrane of rat Schwann cells was generated. This antibody bound to Schwann cell surface but not to fibroblasts in mixed neonatal sciatic nerve cultures. It did not bind to cells in newborn rat brain or corpus callosum cultures that contained oligodendrocytes, astrocytes, fibroblasts and neurons. The target antigen for this monoclonal antibody disappeared from Schwann cell surface after 5 days in culture. At this time, addition of 10(-3) M 8-bromo cyclic AMP or 10(-3) M dibutyryl cyclic AMP resulted in the reappearance within 2 days, of the target antigen on Schwann cell surface membrane. The reappearance of this epitope parallels that of surface galactocerebroside on Schwann cells when incubated with cAMP analogues. Re-expression of the target antigen for this monoclonal antibody in the presence of cAMP is evidence that cAMP may be a signal for synthesis of a variety of myelin molecules and as such could be a signal for myelination of axons by Schwann cells.

Animals↗