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T Mitsuma

Publications and source records attributed to T Mitsuma.

At least 235 records · Page 13Linked to original sources
PubMed1989

[Expression of nerve growth factor receptor in human benign peripheral nerve sheath tumor].

We examined in vivo and in vitro expression of nerve growth factor (NGF) receptors in 13 dermal and 9 plexiform neurofibromas, 28 schwannomas, and 4 traumatic neuromas with an immunohistochemical method using a monoclonal antihuman NGF receptor antibody (ME20-4) and anti S-100 beta protein antibody. Immunoreactivity for NGF receptor and S-100 beta protein was universally observed on the principal cells of both neurofibroma and schwannoma in vivo. Moreover, we examined the NGF receptor and S-100 beta protein immunoreactivity in the culture system of the neurofibroma and schwannoma with an immunofluorescent double staining method. The principal cells of both tumors were positively stained by both ME20-4 and anti S-100 beta protein antibodies. These cells also express the ability for 125I-NGF binding, which was examined with an autoradiographic technique. These results suggest that NGF receptors are universally expressed on the S-100 beta protein positive Schwann-like cells composing of these tumors both in vivo and in vitro. In traumatic neuroma, however, a positive staining of NGF receptor was more strongly observed in the perineurium rather than in the endoneurial cells.

Adolescent↗
PubMed1989

Effect of endogenous opioid peptides on TRH release from rat stomach in vitro.

The effect of endogenous opioid peptides (beta-endorphin, leucine-enkephalin, dynorphin 1-13 on the release of thyrotropin releasing hormone (TRH) from the rat stomach in vitro was studied. The rat stomach was incubated in the medium 199 with 1.0 mg/ml of bacitracin (pH 7.4) (medium) and the amount of TRH released into the medium was measured by radioimmunoassay. The release of TRH from the rat stomach was inhibited significantly in a dose-related manner with the addition of endogenous opioid peptides, but not affected with naloxone. However, the inhibitory effect of endogenous opioid peptides on TRH release from the rat stomach was prevented by the addition of naloxone. These findings suggest that endogenous opioid peptides inhibit TRH release from the rat stomach in vitro.

Animals↗
PubMed1989

[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↗
PubMed1989

[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↗
PubMed1989

[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↗
PubMed1989

[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↗
PubMed1989

[Two cases of myasthenia gravis associated with transient amenorrhea].

Two cases of acquired autoimmune myasthenia gravis (MG) presenting transient amenorrhea were reported. Case 1, 28 years old, developed blepharoptosis and generalized fatigability at the age of 20 years. She had been treated only by anti-cholinesterase. Amenorrhea appeared at the age of 26 years. Then, physical examinations showed normal secondary sexual development and moderate myasthenic features. On laboratory examinations, SLE findings such as leucopenia (1,600/mm3), biologically false positivity in the serological tests for syphilis, negative Mantoux reaction, positive anti-nuclear and -DNA antibodies, were noted. Anti-AChR antibody was highly positive (max.: 353 nmol/l). Decreased E2 (13-15 pg/ml) and progesterone (0.21-0.29 ng/ml) values in serum, elevated LH (110-160 mIU/ml) and FSH (78-90 mIU/ml) and highly reactive LH-RH loading test were consistent with the hypergonadotropic hypogonadism. Thymus pathology of thymectomy which was done during amenorrhea, showed hyperplasia. Bilateral ovarian biopsy revealed a number of arrested primordial follicles, but neither inflammatory changes nor fibrosis. Immune complexes were not localized in the ovarian biopsy. The Kaufmann's therapy aggravated myasthenic symptoms. Menstruation recurred after 13 months of thymectomy. Amenorrhea continued for 18 months. Case 2, 37 years old, has had anti-epileptic regimens since the age of 4 years. She has been highly myasthenic for 15 years and treated by thymectomy, steroid hormone, plasmapheresis and some other therapies for 10 years. Amenorrhea occurred at the age of 34 years. Sexual development was normal. Myasthenia was very severe. On laboratory examinations, anti-AChR antibody was positive (max.: 941 nmol/l). Transient elevation of serum LH (37 mIU/l) and FSH (14 mIU/l) values was observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

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↗
PubMed1988

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↗
PubMed1988

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↗
PubMed1988

Effects of thyrotropin releasing hormone on human sudomotor and cutaneous vasomotor activities.

At an ambient temperature of 34-41 degrees C (rh = 40%) forearm sweat rates were measured by capacitance hygrometry in 9 male volunteers. Thyrotropin releasing hormone (TRH) was infused intravenously at 0.1 mg.min-1 for 20 to 30 min. Sweat rate increased rapidly within a minute after initiation of TRH infusion, decreased rapidly after the peak sweat rate was attained in 2-5 min of TRH infusion, and then levelled off in 6-10 min near the level before TRH infusion. Core temperature (Tre, Tty) started to decline at the time of the peak sweat rate and levelled off almost coincidentally with the levelling off in sweat rate. Average values for the rate of sweat expulsions (Fsw), sweat rate and mean body temperature (Tb) were obtained from the data of the last 10 min period of TRH infusion. The regression line for the relationship of Fsw to Tb shifted during the TRH infusion to the left of the line for the control; that of sweat rate to Fsw hardly shifted. At an ambient temperature of 24-27 degrees C TRH produced vasodilation as evidenced by an increase in skin blood flow (measured by means of thermal distribution), an increase in amplitude of the photoelectric plethysmogram and an elevation of skin temperature in the finger tips. It is suggested that TRH may act, either directly or indirectly, on the central thermoregulatory mechanism (or on the thermoreceptive mechanism) to lower the reference temperature for heat dissipation.

Adult↗
PubMed1988

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↗
PubMed1988

Changes of monoamine and TRH contents in naloxone induced inhibited development of rat cerebrum and cerebellum.

We have studied effects of an opioid antagonist, naloxone (NLX) on rat brain development. Newborn rats were given daily subcutaneous injection of 1 or 50 mg/kg NLX from birth until weaning (day 21). The 28 day-old rats were examined their brain development. Both doses of NLX reduced the cerebral and cerebellar weights of rats but the body weight loss was significant only in the higher dose (50 mg). However, there were neither morphological changes in the central nervous system nor movement disorders such as abnormal gait and involuntary movements in naloxone treated rats (NLX-rats). We found that serotonin content was decreased significantly in the cerebral cortex and medulla while it was significantly increased in the pons and striatum of NLX-rats. Noradrenaline was decreased significantly in the medulla while it was increased in the pons of the NLX-rats. In contrast, the concentrations of these monoamines did not show any changes in cerebellum and hippocampus of NLX-rats. On the other hand, thyrotropin-releasing hormone (TRH) was significantly decreased in cerebellum and hippocampus of NLX-rats, while it did not show any changes in cerebral cortex, medulla and pons of NLX-rats. These observations suggest that the neurotransmitters influencing the brain development, which are modulated by endogenous opioid systems, may play an important role in the development of rat brain; monoaminergic neurons play a significant role in the development of the cerebrum while TRH containing neurons may be involved in that of the cerebellum.

Animals↗
PubMed1988

Effects of eel calcitonin on plasma beta-endorphin-like immunoreactivity levels in rats.

The effect of synthetic eel calcitonin (CT) on the level of plasma beta-endorphin-like immunoreactivity (beta-En-LI) and on its content in hypothalamus and anterior pituitary in vivo and on the release of beta-En-LI-from anterior pituitary in vitro was studied. The level of beta-En-LI was increased significantly in a dose-dependent manner after the injection of 1-100 U/kg CT, maximum level being found at 10 min after the injection. After the administration of 50 U/kg CT, the increase was still significant at 40 min. Such an increase was not found in hypophysectomized animals. The content of beta-En-LI in the hypothalamus and anterior pituitary did not change significantly after CT injection. In vitro, the release of beta-En-LI from anterior pituitary was enhanced significantly after CT. It may be concluded that CT acts on the pituitary to increase the release of beta-En-LI which results in increased plasma level.

Animals↗
PubMed1988

Synthetic eel calcitonin stimulates thyrotropin releasing hormone release from rat stomach in vitro.

The effect of synthetic eel calcitonin on the release of thyrotropin releasing hormone (TRH) from the rat stomach in vitro was studied. The rat stomach was incubated in medium 199 with 1.0 mg/ml of bacitracin (pH 7.4) for 20 min. The amount of TRH released into the medium was measured by radioimmunoassay. After the addition of synthetic eel calcitonin the release of immunoreactive TRH from the rat stomach in vitro was enhanced significantly in a dose-related manner. Elution profile of acid-methanol-extracted rat stomach on Sephadex G-10 was identical to that of synthetic TRH. The findings suggest that synthetic eel calcitonin stimulated TRH release from the rat stomach in vitro.

Animals↗