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Biomedical subjects

S Ueno

Publications and source records attributed to S Ueno.

At least 325 records · Page 18Linked to original sources
PubMed1989

Electrophoretic immunoblotting analysis of anti-thymus microsome antibodies in patients with myasthenia gravis.

Anti-thymus microsome antibodies and anti-skeletal muscle microsome antibodies in sera from patients with myasthenia gravis (MG) were analyzed by means of immunoblotting, which was performed after SDS polyacrylamide gel electrophoresis of antigens to clarify the pathogenic role of the thymus in MG. Anti-thymus microsome antibodies were detected in 15 of the 20 cases of MG examined. The detection frequency (75%) was significantly higher than the corresponding frequency determined for anti-muscle microsome antibodies (35%) in the same group of patients. Thymic antigens with a molecular weight of 38 kilodaltons (KD), 60 KD and 220 KD were often recognized by antibodies in sera from MG patients studied here. The anti-thymus microsome antibodies were not cross-reactive with either thymic acetylcholine receptors or lymphocyte surfaces. These findings indicated that the specific antibodies were produced to the thymic microsomal fraction, and its frequency was higher than has been suspected in MG patients.

Adolescent↗
PubMed1989

Glutamate metabolism of leukocytes and skin fibroblasts in spinocerebellar degeneration with lowered glutamate dehydrogenase activity.

From 21 patients with spinocerebellar degeneration 5 had markedly decreased glutamate dehydrogenase (GDH) activities and high values of serum plasma glutamate level after oral glutamate loading tests. Skin fibroblasts from patients with GHD deficiency showed intracellularly higher glutamate and lower glutathione contents than those from controls and showed significantly decreased viability in L-glutamate-containing medium. These data suggest that glutamate toxicity may at least play a part in this degeneration process.

Adolescent↗
PubMed1989

Cellular localization of müllerian inhibiting substance in the developing rat ovary.

The ontogeny of Müllerian Inhibiting Substance (MIS) production was studied in the immature developing rat ovary using immunohistochemistry and bioassay. In a graded organ culture assay, in which regression of the Müllerian duct of the 14 1/2-day rat fetus was used as a measure of bioactivity, MIS could not be detected in ovarian fragments from fetal rats. After birth, however, MIS bioactivity first became detectable at 4 days of age. Fragments from ovaries of rats 7 days of age and older contained moderate levels of MIS activity which remained detectable throughout the prepubertal period, although extreme individual variability was characteristic. A rabbit polyclonal antibody against human recombinant MIS was used to localize MIS in rat ovarian tissue. Avidin-biotin enhanced immunoperoxidase staining could not detect MIS in the 15-day fetal or 1 day postnatal ovary, where no follicular growth was noticed. In ovaries from rats 1 week or older, where follicular growth was apparent, MIS could be localized specifically and exclusively in the cytoplasm of granulosa cells. MIS was found more in the innermost layers of granulosa cells than in the peripheral layers in preantral follicles. In antral follicles, MIS was found predominantly in the cumulus oophorus cells and periantral cells. In these developing ovaries, MIS could not be found in follicles with features of atresia.

Aging↗
PubMed1989

Mullerian inhibiting substance in the adult rat ovary during various stages of the estrous cycle.

Mullerian inhibiting substance (MIS) in the adult rat ovary can be detected by immunohistochemistry in the granulosa cells of growing preantral follicles and in the cumulus oophorus and periluminal granulosa cells of antral follicles in estrus, metestrus, diestrus, and proestrus. Neither the corpus luteum nor atreitic follicles stained for MIS. During proestrus, dramatic changes occurred in the large preovulatory antral follicles, which early in the day manifest intense MIS-specific staining in the granulosa cells located close to the oocyte, however, at 2300 h, just before ovulation when the germinal vesicle was extruded to indicate resumed meiotic division, MIS staining waned. When the morphology of the late preovulatory stage was created experimentally in 26-day-old immature ovaries by stimulating 48 h earlier with hCG, the intense staining of the granulosa cells surrounding the oocytes from untreated ovaries was lost in the cumulus cells of such hCG-treated animals. This temporal pattern of MIS staining and the prior demonstration that MIS could inhibit in vitro meiosis of oocytes from untreated immature rats suggest that this regressor, well characterized in the fetal testis, might function in the ovary as a regulator of oocyte maturation and follicular development during the adult reproductive cycle.

Animals↗
PubMed1989

Long-term coenzyme Q10 therapy for a mitochondrial encephalomyopathy with cytochrome c oxidase deficiency: a 31P NMR study.

For 2 years we administered high doses of coenzyme Q10 (CoQ) to a patient having mitochondrial encephalomyopathy with cytochrome c oxidase deficiency. Abnormal elevation of the serum lactate per pyruvate ratio and the increased concentration of serum lactate plus pyruvate induced by exercise decreased with CoQ treatment. This therapeutic effect continued for 2 years. 31P nuclear magnetic resonance spectroscopy showed acceleration of the postexercise recovery of the ratio of phosphocreatine to inorganic phosphate in muscle during CoQ treatment. These observations support the beneficial effect of CoQ on the impaired mitochondrial oxidative metabolism in muscle. Also, impaired central and peripheral nerve conductivities consistently improved during CoQ treatment. These results indicate that CoQ has clinical value in the long-term management of patients with mitochondrial encephalomyopathies, even though there are clinical limitations to the effects of this therapy.

Adult↗
PubMed1989

Induction of lipid peroxidation in mice by hexavalent chromium and its relation to the toxicity.

Comparative effects of hexavalent (K2Cr2O7:Cr(VI)) and trivalent chromium (Cr(NO3)3:Cr(III)) on the development of lipid peroxidation, and the relationship between the lipid peroxidation and damage to tissues were studied using male ddY strain mice. The animals were administered with either of two chemicals at a dose of 20 mg Cr/kg by a single intraperitoneal injection. The results obtained were as follows: (1) Lipid peroxidation in the liver, as measured by the synthesis of thiobarbituric acid reactive substances (TBARS), showed a significant increase at 24 and 48 hr after Cr(VI) injection, while in the kidney it was observed only at 48 hr. In the mice administered with Cr(III), TBARS formation in the liver went down below the control levels, while no change was observed in the kidney. (2) Chromium contents in the liver and kidney showed a maximum level at 6 hr after injection of Cr(VI) and then those declined to the half of the maximum level at 48 hr, respectively. Chromium contents in the liver and kidney of the mice injected with Cr(III) were lower than those injected with Cr(VI) during the experimental period. (3) Increases of TBARS formation in the liver, chromium content in the liver and kidney, and ornithine carbamyl transferase (OCT) activity indicative of the liver cell damage, and urea nitrogen content in the serum, indicative of the kidney damage, observed at 24 hr after injection of Cr(VI) were inhibited by simultaneous injection of 100 mg/kg of L-ascorbic acid, as antichrome agent, respectively. These observations might suggest a possible causative role of lipid peroxidation in Cr(VI) toxicity.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Cellular injury and lipid peroxidation induced by hexavalent chromium in isolated rat hepatocytes.

In order to elucidate the relationship between cellular injury and lipid peroxidation induced by hexavalent chromium (CrVI), isolated rat hepatocytes treated with any one of scavengers of active oxygen species, antioxidants or antichromium agent were incubated with K2Cr2O7 as CrVI (1 mM Cr). After the incubation, the development of lipid peroxidation was determined as thiobarbituric acid (TBA)-reacting materials in total lipid extracts from the incubated hepatocytes. Cellular injury was observed as a leakage of lactate dehydrogenase (LDH) from hepatocytes into incubation medium. The contents of reduced glutathione (GSH) in hepatocytes were also assessed. Results obtained were as follows: (1) CrVI facilitated lipid peroxidation in isolated hepatocytes after 20 min of incubation. On the other hand, the cellular injury induced by CrVI was barely observed even after 60 min of incubation. (2) The CrVI-induced lipid peroxidation was inhibited by catalase and mannitol as scavengers of active oxygen species, or N,N'-diphenyl-p-phenylenediamine and alpha-tocopherol as antioxidants. However the cytotoxicity of CrVI could not be prevented by these chemicals. (3) CrVI depleted the contents of intracellular GSH and diminished the activities of glutathione reductase (GR) and glutathione-S-transferase (GST) except glutathione peroxidase. (4) The scavengers of active oxygen species and the antioxidants could not prevent the depletion of intracellular GSH induced by CrVI. (6) Ascorbic acid, antichromium agent, prevented all of the lipid peroxidation, the cellular injury and intracellular GSH depletion induced by CrVI.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

[A case of facioscapulohumeral muscular dystrophy with sensorineural hearing loss and retinal angioma].

We report a sporadic case of 12 years old boy with facioscapulohumeral dystrophy (FSHD), sensorineural hearing loss and exudative angioma of bilateral retina. His hearing loss was noted at 9 years, followed by muscle weakness of his right upper extremity at 11 years. Complete neurological examination at 12 years revealed FSH type distribution of muscle weakness with high serum CK level (330 U/L), moderate sensorineural hearing loss and exudative angiomas of bilateral retina. The biopsy from biceps brachii muscle showed advanced dystrophic changes with a dense inflammatory cell infiltration predominating on perivascular distribution and type II fiber predominance. The features of infiltrating lymphocytic surface antigen seen in this case were compatible with those of FSHD rather than those of polymyositis. In the literature, the association of FSHD with hearing loss and retinal vessel abnormalities has been documented on 15 cases as an unusual form of FSHD. However, it has otherwise been noted that the associations of FSHD and hearing loss or retinal vessel abnormalities are unequivocally frequent, Whenever special attention has been made. Morphological examination with light and electron microscopies on the muscle specimen in this patient did not demonstrate any recognizable abnormality such as arterio-venous shunt or thickening of vessel wall basal lamina. However, it cannot be completely excluded that exudation around the abnormal vessel wall in the muscle may play an initial role in the pathogenesis of FSHD. Further morphological survey on vessel abnormalities may be necessary in the FSHD muscle.

Child↗
PubMed1989

Cytochemical studies on pathological Müller cells after argon laser photocoagulation.

The cytochemical localization of G6Pase activity, which is specific to the endoplasmic reticulum (ER) of Müller cells, was studied after argon laser photocoagulation in the guinea pig retina. After argon laser radiation, Müller cells exhibited enlargement of the cytoplasm, an increase of reactive ER and the nuclei, dislocation of the nuclei and diagonal stretching of the cytoplasm. However, cell attachment between Müller cells and the proliferated pigment epithelial cells or Bruch's membrane differed with the degree of retinal coagulation. This histo- and cytochemical method may be useful for examining Müller cells under various pathological conditions.

Animals↗
PubMed1988

[The role of the sympatho-adrenomedullary system and adrenergic receptors in the pathogenesis of orthostatic hypotension in diabetes mellitus].

To clarify the role of the sympatho-adrenomedullary and renin-angiotensin-aldosterone systems, and catecholamine receptors, in the pathogenesis of orthostatic hypotension in diabetes mellitus (DM), urinary excretion of catecholamines, and plasma levels of norepinephrine (PNE), epinephrine (PE), renin activity (PRA), aldosterone (PAC), cyclic AMP (PcAMP) and cyclic GMP (PcGMP) were measured in 16 normal subjects (N) and 50 diabetic patients with or without orthostatic hypotension (DMOH(+), DMOH(-)). Changes in PNE, PE, PRA, PAC, PcAMP and PcGMP by standing, glucagon (G) administration and cold pressor test were examined. Furthermore, the effect of metoclopramide on catecholamine levels and blood pressure was investigated before and after cold pressor test. The results were following; (1) Urinary free norepinephrine excretion was significantly lower in DMOH(+), while urinary total norepinephrine excretion was normal in the two DM groups. Urinary free and total epinephrine excretions were lower in DMOH(+) than in N and DMOH(-). (2) PNE and PE were elevated after standing in all groups tested, and more pronounced in some cases of DMOH(+). Although PRA and PAC were elevated normally after standing in all groups, a dissociation between the two parameters was seen in some cases of DM. PcAMP after standing was correlated with PE(r = 0.829). Basal PcGMP was high in many cases of DMOH(+). However, no difference in the elevation of PcGMP after standing was noted between N and the two DM groups. (3) Systolic blood pressure (SBP) rose markedly in only DMOH(+) from 146 +/- 27mmHg to 178 +/- 34mmHg 5 minutes after G administration. The increment of PNE and PE 5 minutes after G administration were similar in all groups. In only DMOH(+), the increase in PcAMP 15 minutes after G test was proportional (r = 0.498) to that of epinephrine. (4) Responses of SBP, PNE, PE and PAC to cold pressor test apparently improved after administration of metoclopramide (MC) in some patients with DM. These results suggest that not only organic disturbance of sympathetic nerves but also functional inhibition of norepinephrine release mediated by dopamine receptor, may play an important role in the pathogenesis of orthostatic hypotension in diabetes mellitus. It is considered that catecholamine secretion from the adrenal medulla in DMOH(+) is increased by hypotension induced by standing. Furthermore, the vascular response to catecholamines may be accelerated through the increment of the extrajunctional receptor in DMOH(+).(ABSTRACT TRUNCATED AT 400 WORDS)

Adrenal Medulla↗
PubMed1988

[Inhibitory effects of somatostatin analog (SMS 201-995) on pancreatic hormones in patients with malignant islet-cell carcinoma].

Acute effects of somatostatin analog (SMS 201-995) on pancreatic hormones were studied in two patients with malignant islet-cell carcinoma. Before and after subcutaneous injection of somatostatin with a doses of 50 micrograms, blood glucose (BG), serum growth hormone (hGH), C-peptide immunoreactivity (CPR), plasma immunoreactive glucagon (IRG) and gastrin were assayed, and changes in elution patterns of IRG and gastrin were also analyzed on Bio-Gel P-30 column chromatography. In Patient 1 with glucagonoma syndrome and hypergastrinemia, a prompt and remarkable decrease in plasma IRG and gastrin was observed after the injection of SMS 201-995 in association with a decrease in blood glucose, and then IRG and gastrin increased gradually. The suppressive effect continued for at least 6 hours. On gel filtration of the plasma obtained before the injection of the analog, three major peaks, greater than 20000, 9000 and 3500 molecular-weight (mol wt) fractions, were seen in IRG fraction. The decrease in plasma IRG observed at 1 hour after the injection was mainly due to a marked decrease in the 3500 molecular weight fraction. In addition, a slight decrease in the 9000 mol wt fraction was seen. At 4 hours after the injection, the 3500 mol wt peak returned to the previous level, while the 9000 mol wt peak decreased further. On the other hand, the gastrin elution pattern of plasma obtained before the injection revealed three major gastrin peaks, greater than 20000, 7000 and 5000 mol wt fraction. The changes in the gastrin elution pattern after the injection were similar to those of the IRG elution pattern. In Patient 2 with Zollinger-Ellison's syndrome, the plasma gastrin level decreased gradually for 5 hours after the injection. On gel filtration of the plasma obtained before the injection, two major gastrin peaks, 7000 and 5000 mol wt fraction, of which the large-molecular fraction was more prominent than the small-molecular fraction, were observed. After the injection, a marked decrease in the small-molecular fraction and a gradual decrease in the large-molecular fraction were observed for 4 hours, accompanied by a decrease in plasma gastrin. At 7 hours after the injection, the smaller fraction was augmented again. The serum CPR and hGH was slightly suppressed after the injection in both patients. The adverse effects of slight nausea and vomiting were noticed only in Patient 1.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenoma, Islet Cell↗
PubMed1988

Suncus murinus as a new experimental model for motion sickness.

Characteristics of motion sickness and effects of possible prophylactic drugs were studied using Suncus murinus (house musk shrew) for its potential use as an experimental model in motion sickness. Mild reciprocal shaking (amplitude: 10-40 mm; frequency: 0.5-3.0 Hz) induced vomiting in most of Suncus murinus within 2 min. Adaptation was observed when the motion stimulus was repeated with an interval of 2 to 3 days. During the repetitive motion training, both the ratio of sensitive animals and the number of vomiting episodes decreased, and the time from the start of shaking to the first vomiting was extended. Subcutaneous injection of scopolamine (100 mg/kg), chlorpromazine (8 mg/kg), promethazine (50 mg/kg), diphenhydramine (20 mg/kg), chlorphenylamine (20 mg/kg) and methamphetamine (2 mg/kg) decreased the emetic effect of motion sickness, but pyrilamine (20 mg/kg), meclizine (20 mg/kg) and dimenhydrinate (32 mg/kg) were not effective or very weak. These results indicate that the Suncus murinus is sensitive to the motion stimulus and antiemetic drugs are effective as prophylaxis. The Suncus murinus is useful as a new experimental animal model for motion sickness.

Acceleration↗
PubMed1988

Effects of a high concentration of CO2 on electrocardiograms in the carp, Cyprinus carpio.

1. The effects of a high concentration of CO2 (PCO2 = 250 mmHg and PO2 = 360 mmHg in water) and MS222 (tricaine methanesulfonate, 1/8000 or 1/5000) on the electrocardiogram (ECG) in carp were examined using five kinds of bipolar leads from the body surface. 2. In the carp anesthetized with the high concentration of CO2 for 30 min, the QRS duration, PQ interval and and direction of the QRS axis on the frontal plane significantly changed. Even after recovery from anesthesia, delay in the QRS duration was still recognized. 3. The concentration of CO2 used in this study had an anesthetic action to the same degree as 1/8000 of MS222 and had a much more severe effect on the ECG of the carp than 1/5000 of MS222.

Animals↗
PubMed1988

Electrocardiograms in five bipolar leads recorded from the body surface of three fish species (Cyprinus carpio, Oreochromis niloticus and Pagrus major) in fresh or sea-water.

1. ECGs were recorded using five bipolar leads from the body surface of porgy Pagrus major and tilapia Oreochromis niloticus in fresh or sea-water, or held on a dry towel. 2. The maximum QRS amplitude was detected in lead V in both species being 54 +/- 25 microV in porgy and 241 +/- 78 microV in tilapia, respectively, when the fish were held on the dry towel. 3. Clear ECG waves could not be obtained from porgy in sea-water because of the porgy's small cardiac potential and leakage of the potential. However, clear ECG waves could be obtained in sea-water from the body surface of tilapia, with the average QRS amplitude being 35 +/- 8 microV. 4. The mean electrical P and QRS axes in tilapia were directed toward almost the same direction (frontal downward), whereas both P and QRS axes in most carp were in opposite directions. In porgy, the relationship between the P and QRS axes could not be identified due to the smaller amplitude of the P wave.

Animals↗
PubMed1988

Decreased glutamate dehydrogenase protein in spinocerebellar degeneration.

A radioimmunoassay system for determining content of glutamate dehydrogenase (GDH) in human leukocytes was established and studied in 14 patients with spinocerebellar ataxia or atypical Parkinsonism. The protein content of leukocyte GDH was decreased in four patients and the reduction in the protein content was proportional to that in the enzyme activity. The ratio of GDH activity to protein content was invariable in healthy controls, diseased controls and patients with reduced GDH activity. These results suggested that at least a portion of the partial GDH deficiency was due to the decreased level of the enzyme protein.

Adult↗