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Biomedical subjects

T Satoh

Publications and source records attributed to T Satoh.

At least 1,081 records · Page 60Linked to original sources
PubMed1987

Cadmium-induced osteopathy: clinical and autopsy findings of four patients.

Clinical and autopsy findings of 4 patients with chronic cadmium toxication by peroral uptake of cadmium are reported. Cadmium toxication was liable to occur in multiparous postmenopausal women, and it began with proteinuria, glycosuria, lumbago and bone pain. Then, renal function gradually decreased being accompanied with renal tubulopathy. Autopsy disclosed renal tubulopathy, which consisted of the flattening of the epithelium of proximal convoluted tubules at the peripheral portion and the mild thickening of the tubular basement membrane. There was no primary change in the glomerulus and renal interstitium. Osteomalacia was observed in the vertebrae and several other bones. The degree of osteomalacia was in good agreement with chronic renal tubular dysfunction. A decrease of the estrogen content, in addition to renal tubulopathy due to biological saturation of cadmium, seems to play an important role in the pathogenesis of cadmium-induced osteomalacia.

Acidosis, Renal Tubular↗
PubMed1987

Preventive effects of the cerebral circulation improver 6,7-dimethoxy-1-(3,4-dimethoxybenzyl)-4-([4-(2-methoxyphenyl)- 1-piperazinyl]methyl)isoquinoline on stroke symptoms in stroke-prone spontaneously hypertensive rats.

Stroke-prone spontaneously hypertensive rats (SHRSP) were treated with food admixed, 6,7-dimethoxy-1-(3,4-dimethoxybenzyl)-4-([4-(2-methoxyphenyl)-1- piperazinyl]methyl)isoquinoline (Ro 22-4839), a novel cerebral circulation improver, for a period of 15 weeks starting from 5 weeks of age at an average daily dose of 30.6 or 66.0 mg/kg. As compared with normotensive Wistar Kyoto rats, SHRSP in the control group rapidly developed severe hypertension (244 mmHg at the end of the experiments) accompanied with deterioration of cardiovascular parameters including left ventricular hypertrophy, reduction in pumping ability and increase in peripheral vascular tone. At 20 weeks of age (i.e. at the end of experiments), 75% of SHRSP developed stroke signs and concomitant cerebral edema evidenced by the increases in water and sodium contents in the brain. These stroke symptoms were accompanied with a profound externalized shape change of erythrocytes after in vitro treatment with Ca2+ and ionophore A23187, an increased plasma level of thiobarbituric acid reacting substance (TBARS), a measure of lipid peroxides, and a decreased sensitivity of platelets to ADP. The long-term treatment with Ro 22-4839 prevented the progress of stroke and cerebral edema, although the deteriorated cardiovascular parameters were not prevented by the treatment. This compound was also found to prevent the hypersusceptibility of erythrocyte membrane to Ca2+-ionophore and Ca2+, the hypoaggregability of platelets and the elevated plasma TBARS in SHRSP. These results indicate that the beneficial effects of Ro 22-4839 in SHRSP may be attributable to its calmodulin antagonistic and anti-lipid peroxidative actions but not to its hypotensive action.

Animals↗
PubMed1987

Photoactivation mechanism of hyaluronidase by chlorpromazine.

A pre-irradiated chlorpromazine (CPZ) in pH 7.2 and aqueous solutions activated hyaluronidase, and it showed the enzyme-activating action even after 7 days of irradiation. This indicates that the stable photoproducts of CPZ activated the enzyme. But promazine and CPZ-5-sulfoxide, which are photoproducts of CPZ, did not activate the enzyme in the presence and absence of UVA. The dimer and higher molecular weight (MW) products of CPZ that were obtained by treating the pre-irradiated CPZ solution with gel permeation chromatography showed the hyaluronidase by activating action without UVA. In addition, photoactivation of hyaluronidase by CPZ was inhibited by radical quenchers. This suggested that the photoproducts with enzyme-activating action were produced via some radicals. On the basis of these findings, a possible mechanism for photoactivation of hyaluronidase by CPZ was proposed.

Animals↗
PubMed1987

[Application of the RI-counting method in CSF rhinorrhea].

Some diagnostic procedures for CSF rhinorrhea have been reported, but they can not always identify and localize CSF leakage. This method, using intranasal cotton pledgets after the intrathecal injection of radioisotope (111In-DTPA) is thought to be reliable, informative and innocuous for localizing the sites of CSF leakage. This technique was named RI-counting method, and applied in two cases that were difficult to diagnose especially with positional-loading. The patients were first in the supine position, then in the sitting position, after the intrathecal injection of radioisotope and the intranasal insertion of cotton pledgets. After exchanging these pledgets, the patients were set in the prone position. After measuring the radioactivity of these pledgets and of 1 ml of blood, the ratios of the radioactivity of the pledgets to that of the blood were calculated. In case 1 the ratios of the left sphenoethmoid recess and the left middle meatus were significantly higher when the patient took the prone position, but in the supine or sitting position the ratios were in the normal range. In case 2 the ratio of right olfactory cleft was significantly higher in the sitting position or neck flexion. Both cases were operated and demonstrated that the location of the CSF leakage was presumable by using RI-counting method, regarding the anatomical relationship between the intranasal sites of pledgets and the opening of the paranasal sinuses. Positional-loading seemed to be essential. We obtained 72 pledgets of patients without CSF rhinorrhea, and the ratios of radioactivity of these pledgets had a mean value (M) of 0.156 and a standard deviation (SD) of 0.107.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebrospinal Fluid Rhinorrhea↗
PubMed1986

Stereospecificity of diacylglycerol for stimulus-response coupling in platelets.

In intact platelets, a permeable diacylglycerol having a 1,2-sn- but not 2,3-sn- configuration activated protein kinase C directly. In the presence of Ca2+-ionophore this diacylglycerol caused full activation of platelet release reaction. 1,3-Isomer was inactive. Among these isomers only 1,2-sn-diacylglycerol was converted rapidly to the corresponding phosphatidic acid in both intact and broken cell preparations. Thus, the diacylglycerol which functions in stimulus-response coupling possesses a 1,2-sn-glycerol backbone, and other isomers are not involved in the signal transduction through the protein kinase C pathway.

Blood Platelets↗
PubMed1986

Purification and characterization of an endothelial cell growth factor from serum-free culture medium of human diploid fibroblast cells.

Serum-free culture supernatants of human embryo fibroblast cells contain endothelial cell growth factor (f-ECGF) which supports the serial propagation of human umbilical vein endothelial cells in the serum-free culture medium (medium A). This growth-stimulating activity has been partially purified from serum-free culture-conditioned medium. The stability of the activity to acid (pH 4.0-4.5) was utilized for the first step in purification. f-ECGF had a high affinity to heparin-Sepharose CL-6B, and was isolated by the methods of heparin affinity, of ion-exchange and gel filtration chromatography from the serum-free culture-conditioned medium preparation. The purified f-ECGF had an isoelectric point in the pH range 4.5-6, and a molecular weight of approx. 30 kDa determined by either gel filtration or SDS-polyacrylamide gradient gel electrophoresis. The f-ECGF has high affinity for concanavalin A column, and the activity was partially eluted from the column with ethylene glycol and alpha-methylmannose. The results indicate that f-ECGF is an acidic-glyco-protein with heterogeneous sugar chain(s).

Cell Line↗
PubMed1986

Prominent glutamine oxidation activity in mitochondria of avian transplantable hepatoma induced by MC-29 virus.

Well coupled mitochondria were isolated from transplantable chicken hepatoma induced by MC-29 virus. The mitochondrial phosphate-dependent and phosphate-independent glutaminase activities were increased compared with those from normal chicken liver. Glutamate dehydrogenase was undetectable in the tumor mitochondria. Oxypolarographic tests showed the following: glutamine oxidation was prominent in the tumor mitochondria and was mediated through an NAD-linked reaction, while mitochondria from the liver showed a feeble glutamine oxidation; glutamine oxidation by tumor mitochondria was inhibited either by aminooxyacetate, inhibitor of transaminases, or prior incubation of mitochondria with DON (6-diazo-5-oxonorleucine), which inhibited mitochondrial glutaminases. Bromofuroate, inhibitor of glutamate dehydrogenase, had little or no effect; and glutamate oxidation was also inhibited by aminooxyacetate, while it was not affected by DON. These findings clearly show a high glutamate oxidation activity in the hepatoma and indicate that the product of glutamine hydrolysis, glutamate, is catabolized via transamination in the mitochondria to supply ATP.

Animals↗
PubMed1986

Muscle-specific beta-enolase concentrations after cross- and random innervation of soleus and extensor digitorum longus in rats.

The concentration of beta-enolase, a highly specific marker of the skeletal muscle of rats, was determined in a slow-twitch muscle, the soleus (SOL) and a fast-twitch muscle, the extensor digitorum longus (EDL) after cross-innervation, random reinnervation, or denervation. The beta-enolase concentration is normally high in EDL and low in SOL. When the nerves entering into these muscles were cross-sutured, the beta-enolase concentration in EDL decreased and that in SOL increased to reach an almost equal value in 20 weeks and by the 35th week the SOL ultimately had a higher beta-enolase concentration than the EDL. When the sciatic nerve trunk was completely transected and sutured immediately, the beta-enolase concentration in EDL decreased and that of SOL increased; in 20 weeks SOL had a beta-enolase concentration similar to that of the EDL. When these muscles were denervated by cutting the sciatic nerve trunk, their beta-enolase concentrations were markedly lowered, but EDL still retained on the 12th week a beta-enolase value comparable to the normal SOL. Possible mechanisms behind the observed changes in beta-enolase concentration are discussed.

Animals↗
PubMed1986

Glutamine metabolism in the avian host bearing transplantable hepatomatous growth induced by MC-29 virus.

The concentrations of free amino acids have been determined in the sera of chickens bearing transplanted hepatomatous growths induced by MC-29 virus and their pair-fed controls. Decreases in serine and glutamine concentrations were observed when the tumors developed; the latter being more prominent. Glutamine synthetase activities in the liver and thigh muscle were increased as the tumors grew larger. Elevation of serum uric acid was observed in the tumor-bearing chickens. Liver glutamine-PRPP-amidotransferase activity was not affected by the tumor growth. In the hepatomatous tissue, activity of glutamine synthetase was low and below one-tenth of that in liver. Glutaminase activities, phosphate-dependent and phosphate-independent, were increased. Glutamine-PRPP-amidotransferase activity was about half compared to that in liver.

Amidophosphoribosyltransferase↗
PubMed1986

Inhibition of the formation of 13,14-dihydroprostaglandin F2-alpha induced by chlorpromazine in rat ovary.

The present study was designed to investigate the effects of chlorpromazine (CPZ) on the formation of 13,14H2-PGF2 alpha in rat ovary and the possibility that the "critical period" observed in the effect of CPZ for the blockade of ovulatin may be appreciated by measuring the formation of 13,14H2-PGF2 alpha as a parametor. When CPZ (4.0 mg/kg) was given s.c. at 10:00 a.m. once a day for 3 days from the first day of diestrus to the expected day of proestrus followed by sacrifice after 24 hours of the final injection, a significant inhibition was recognized in the formation of 13,14H2-PGF2 alpha in ovary. The effects of a single injection of CPZ were also determined 24 hours after injection at 10:00 a.m. on the day of diestrus I, diestrus II or proestrus. The results showed that the drug treatment on the day of proestrus significantly decreased the formation of 13,14H2-PGF2 alpha, but not on the day of diestrus I or II. When the formation of ovarian 13,14H2-PGF2 alpha was inhibited by CPZ treatment, the blockade of ovulation was also confirmed. A single injection of CPZ at 05:00 and 07:00 after the "critical period" on the day of proestrus did not inhibit the 13,14H2-PGF2 alpha formation in the rat ovary. It is concluded that the administration of CPZ before the "critical period" on the day of proestrus is effective in suppressing the ovarian 13,14H2-PGF2 alpha formation as well as on the blockade of ovulation.

Animals↗
PubMed1986

The pathway of glutamate oxidation in isolated mitochondria from the avian hepatomatous growth induced by MC-29 virus.

The mitochondria isolated from transplantable chicken hepatomatous growth induced by MC-29 virus were deficient in glutamate dehydrogenase. Oxypolarographic tests showed that glutamate oxidation in the tumor mitochondria was initiated via transamination, while glutamate was deaminated by glutamate dehydrogenase in liver mitochondria to supply adenosine triphosphate. Prominent glutamate oxidation and transformation-linked low glutamine synthetase activity may be favorable to the bioenergetics of this fast-growing tumor.

Animals↗
PubMed1986

Inhibitory effect of clomiphene citrate on the conversion of 13,14-dihydro-15-keto-prostaglandin F2 alpha to 13,14-dihydro-prostaglandin F2 alpha in rat ovary.

The effects of clomiphene citrate (clomiphene) on the in vitro conversion of 13,14-dihydro-15-keto-prostaglandin F2 alpha (15KD-PGF2 alpha) to 13,14-dihydro-prostaglandin F2 alpha (13,14H2-PGF2 alpha) in the presence of rat ovarian homogenate, and the relationship between clomiphene and gonadotropin or estrogen in the conversion were investigated. Although clomiphene inhibited the increased conversion of 15KD-PGF2 alpha to 13,14H2-PGF2 alpha by pregnant mare serum gonadotropin (PMS) in rat ovary, the drug did not inhibit the decreased conversion of 15KD-PGF2 alpha by estradiol. The 3-day administration of clomiphene reduced the conversion of 15KD-PGF2 alpha to 13,14H2-PGF2 alpha dose-dependently. A single administration of clomiphene also decreased the conversion, and this decreasing effect was similar to that of estradiol. On the other hand, the repeated administration of clomiphene decreased the ovarian and uterine weights and also inhibited the increase of the uterine weight by PMS or estradiol. These results suggest that clomiphene affects the ovarian enzyme catalyzing the conversion of 15KD-PGF2 alpha to 13,14H2-PGF2 alpha.

Animals↗