Brain stem auditory evoked potentials monitoring in the diagnosis of brain death--clinical application and reliability.
Explore the source record for details and available documents.
Adolescent↗
Biomedical subjects
K Takeuchi
Publications and source records attributed to K Takeuchi.
Bilateral adrenalectomy worsens gastric mucosal lesions induced by indomethacin in the rat. Role of enhanced gastric motility.
The mechanism by which bilateral adrenalectomy worsens indomethacin-induced gastric lesions was investigated in rats. In sham-operated rats subcutaneously administered indomethacin produced gastric lesions at doses of 10 mg/kg body wt or greater, in association with lowering of blood glucose levels. In a parallel study, indomethacin induced gastric hypermotility at the same dose levels but had no effect on acid output or mucosal blood flow even at 25 mg/kg body wt. Adrenalectomy (2 wk) itself significantly reduced the blood glucose levels (approximately 50%) and markedly potentiated the ulcerogenic and motility responses caused by indomethacin; the ED50 values dropped to approximately 10 times lower than those in sham-operated rats. Both acid output and mucosal blood flow were significantly reduced by adrenalectomy, but these values were increased after indomethacin treatment (3 mg/kg body wt). The ulcerogenic and motility responses caused by indomethacin were significantly reduced by acute infusion of glucose (25% wt/wt, 1.2 ml/h) intravenously in both sham-operated and adrenalectomized rats, and by subcutaneous administration of hydrocortisone acetate (10 mg/kg body wt for 2 wk) in the latter group. When the motility and the ulcer score were determined in the same animals, a highly significant relationship was found between these two factors in both sham-operated and adrenalectomized rats. These results suggest that (a) the increased gastric motility may be a key element in the pathogenesis of indomethacin-induced lesions and in the mechanism for aggravation of the lesions and in the mechanism for aggravation of the lesions by adrenalectomy, and (b) abrasion of adrenal glands by inducing hypoglycemia may sensitize the system to indomethacin and increase gastric motility.
Adrenalectomy↗
Delayed healing of acetic acid-induced gastric ulcers in rats by indomethacin.
We examined the mechanism by which repeated administration of indomethacin significantly delays the natural healing of experimental gastric ulcers induced in rats. Gastric ulcers were produced 5 days after injecting 20% acetic acid (0.03 ml) into the submucosal layer of the gastric wall of the antral-oxyntic border. The natural healing of the acetic acid-induced ulcers was extensively delayed by administering indomethacin (1 mg/kg) subcutaneously once daily for 2 or 4 wk. Subcutaneous administration of natural prostaglandin E2 (1 or 3 mg/kg) twice daily for 2 and 4 wk, together with indomethacin, significantly prevented the delay of ulcer healing. Prostaglandin E2 (3 mg/kg) administered twice daily for 2 wk also significantly accelerated the natural healing of the ulcers. A single administration of prostaglandin E2 (1 or 3 mg/kg) significantly reduced histamine-stimulated gastric acid secretion for 4 h in acute fistula rats with 1- or 2-wk-old ulcers, treated with or without daily indomethacin (1 mg/kg). Endogenous prostaglandin E2 levels in the gastric mucosa of normal rats were significantly reduced for at least 12 h after a single or repeated administration of indomethacin (1 mg/kg) for 2 or 4 wk. Gastric mucosal prostaglandin E2 levels in rats with ulcers (5 days after acetic acid injection) were also markedly reduced by indomethacin. This reduction significantly reverted toward control levels after administration of exogenous prostaglandin E2 (3 mg/kg). These results suggest that endogenous prostaglandin E2 plays an important role in the healing process of gastric ulcers.
Acetates↗
Assessment of membrane protection by 31P-NMR effects of lidocaine on calcium-paradox in myocardium.
In studying calcium paradox, perfused rat hearts were used to investigate the myocardial protective effects of lidocaine. Intracellular contents of phosphates were measured using the 31P-NMR method. In hearts reexposed to calcium, following 3 minute calcium-free perfusion, a rapid contracture occurred, followed by rapid and complete disappearance of intracellular phosphates with no resumption of cardiac function. In hearts where lidocaine was administered from the onset of the calcium-free perfusion until 2 minutes following the onset of reexposure to calcium, both intracellular phosphates and cardiac contractility were maintained. Therefore, it can be said that cell membranes were protected by lidocaine.
Animals↗
Sequence variation of the P gene among mumps virus strains.
We have determined nucleotide sequences of a 183-nucleotide long region of the P gene of 10 mumps virus strains after gene amplification mediated by DNA polymerase catalyzed chain reaction (PCR) and have compared them with those of two strains which had been reported earlier (K. Takeuchi et al., J. Gen. Virol., 69, 2043-2049 (1988]. It was shown that mutation is generally noncumulative, i.e., most nucleotide substitutions in earlier strains do not appear in later strains. Viruses of different lineages appeared to cocirculate, but the comparison of American and Japanese strains suggested that those isolated in one country are more closely related to each other than to those isolated in the other country.
Base Sequence↗
Single or repeated electroconvulsive shocks alter the levels of prodynorphin and proenkephalin mRNAs in rat brain.
The effects of single or repeated electroconvulsive shocks (ECS) on the abundance of mRNAs coding for prodynorphin (DYN mRNA) and proenkephalin (EK mRNA) in rat brain were investigated. Rats were given either a single ECS and sacrificed at 0.5, 2, 6, or 12 h post-shock (expt. I), or were subjected to ECS for 1, 3 or 6 days and killed 24 h after the last shock (expt. II). The amounts of DYN mRNA and EK mRNA were measured in several brain regions using RNA blot analysis. In expt. I, a biphasic change in the DYN mRNA level was found in the hippocampus, with an initial 49% decrease at 0.5 h followed by a 51% increase at 6 h after a single ECS. The EK mRNA content in the entorhinal cortex started to increase at 0.5 h, and continued to rise, reaching 260% of the control level at 12 h post-shock. A smaller increase in the EK mRNA level was found also in the hippocampus at 2 to 12 h post-shock. No significant increase in [Met5]-enkephalin or dynorphin A(1-8) immunoreactivity was detected by radioimmunoassay in either area. In expt. II, a dramatic reduction in the DYN mRNA level was observed in the hippocampus 24 h after a single or repeated ECS. In contrast, elevated DYN mRNA levels were seen in the striatum and hypothalamus. The EK mRNA level remained elevated in the entorhinal cortex after 6 daily ECS.(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗
Anaplastic small cell carcinoma of the larynx.
Anaplastic small cell carcinoma of the larynx is an uncommon neuroendocrine tumor. We report a case of this neoplasm of a 53-year-old male. The patient showed persistent hyponatremia accompanied with continuous loss of sodium in the urine, which resulted from inappropriate secretion of antidiuretic hormone (ADH). It is postulated that hyponatremia in this case was due to production of ADH by the tumor cells.
Carcinoma, Small Cell↗
Synthesis and antitumor activity of fused tetracyclic quinoline derivatives. 1.
Several fused tri- and tetracyclic quinolines (I and II) with [2-methoxy-4-[(methylsulfonyl)amino]phenyl]amino or [3-(N,N-dimethylamino)propyl]amino side chains were prepared, and their DNA intercalative properties, KB cytotoxicity, antitumor activity (P388 leukemia), and ability to induce topoisomerase II dependent DNA cleavage were investigated. Some compounds having both intercalative ability and KB cytotoxicity were found to be inactive in vivo. However, a positive correlation was seen between the ability to induce topoisomerase II dependent DNA cleavage and antitumor activity in vivo. The indeno- (13a), benzofuro- (21a), and benzothieno- (22a) quinoline derivatives exhibited potent antitumor activities in vitro and in vivo, comparable to those of m-AMSA. They also intercalate DNA and induce topoisomerase II dependent DNA cleavage. Extended screening of 13a showed it to be active against solid tumors such as M5076 sarcoma, B16 melanoma, and colon 38 carcinoma.
Animals↗
In vitro synthesis of influenza viral RNA: biochemical complementation assay of factors required for influenza virus replication.
Using isolated nuclei prepared from influenza virus-infected HeLa cells, factors affecting the synthesis of two species of positive-sense RNA transcripts, i.e., mRNA and cRNA (complementary RNA to vRNA) were analyzed. In the presence of low concentrations of salt, both mRNA and cRNA were synthesized, whereas in the presence of high concentrations of salt, mRNA was synthesized predominantly. Salt-extracts of nuclei (NE) mainly produced cRNA while mRNA was a major product synthesized by salt-treated nuclei (delta N). In the presence of high concentrations of salt, the NE produced mRNA instead of cRNA. After centrifugation of the NE, the precipitates (NEP) predominantly produced mRNA while the supernatant (NES) alone exhibited a low level of cRNA synthesis activity. With the addition of the NES fraction, mRNA synthesis by the NEP was switched to cRNA synthesis. Glycerol gradient centrifugation of the NES fraction in the presence of high salt yielded vRNA-RNA polymerase complexes that catalyzed mRNA synthesis. These observations indicate that a regulatory factor(s) that can be dissociated from vRNA-RNA polymerase complexes upon exposure to high ionic strength is involved in the switch from mRNA to cRNA synthesis. This activity was not detected in nuclear extracts prepared from uninfected cells, suggesting that such a factor(s) is either encoded by the virus genome or induced by virus infection.
Cations↗
Purification of human lung angiotensin-converting enzyme by high-performance liquid chromatography: properties and N-terminal amino acid sequence.
Angiotensin-converting enzyme from the human lung was purified to apparent homogeneity, using high-performance liquid chromatography following trypsin treatment of the detergent-extract. A 1,750-fold purification was achieved with a 26% yield. The specific activity of the enzyme was 105 units per mg protein with the substrate hippuryl-L-histidyl-L-leucine (HHL) at 37 degrees C, and the Km value for HHL was 1.9 mM. The molecular weight was estimated to be 170,000 by sodium dodecyl sulfate gel electrophoresis, and the isoelectric point was about 4.8, by chromatofocusing. The N-terminal amino acid sequence was (NH2)-X-X-Pro-Gly-Leu-Glu-Pro-Gly-X-Phe-Ser-Ala-Arg-Glu-Ala-Gly-Ala. This is highly homologous to the corresponding sequences of the enzymes from bovine and rabbit lung and from pig, bovine, and mouse kidney, but significantly different from that of the human kidney enzyme.
Amino Acid Sequence↗
Molecular forms of human chorionic gonadotropin in choriocarcinoma serum and urine.
The molecular forms of human chorionic gonadotropin (hCG) were assessed in parallel serum and urine samples from a choriocarcinoma patient by gel chromatography, isoelectric focusing, and Western blot analysis. There were significant qualitative differences in the molecular forms of hCG between the serum and the urine. The serum hCG had a greater molecular weight and a stronger acidic charge than the urinary hCG. These results may be attributed to differences of sialic acid contents. Affinity chromatography using Ricinus communis agglutinin-conjugated Sepharose showed that the serum hCG was completely sialylated, while the urinary hCG was partially desialylated. In addition to the complete hCG molecule, two kinds of hCGbeta-related fragments were detected in the urine of the patient, but not in the serum. In the Western blot using anti-hCGbeta or anti-hCGbeta-CTP under reducing conditions, the urine presented a new band (CTP') with Mr 23,000 in addition to the beta-subunit, while the serum revealed a single band of the beta-subunit with or without a reducing reagent. The present data revealed striking qualitative differences in the molecular forms of hCG between serum and urine of a patient with choriocarcinoma.
Adult↗
Localization and significance of fibronectin in peri-implantation mouse embryos.
This study was performed with the aim of clarifying differences in the localization of fibronectin between embryos developed in vivo and in vitro together with the significance of fibronectin in embryos at implantation. Localization of fibronectin in the embryos was first found in the inner cell mass of the early blastocyst in utero (in vivo group). In contrast, when embryos were cultured in vitro from the 2-cell to the blastocyst stage (in vitro group), fibronectin could not be observed in the late blastocyst. When the blastocysts developed either in vivo or in vitro were further culture for 3 days in Dulbecco's Modified Eagle Medium (D'MEM) containing 10% newborn calf serum, the in vitro implantation (trophoblastic outgrowth in vitro) rates were 90% and 37%, respectively. If the blastocysts developed in vivo were cultured in D'MEM alone, the in vitro implantation rate was as low 29%. However, if fibronectin was added to the D'MEM, instead of newborn calf serum, the in vitro implantation rates were improved. These results led to the conclusion that fibronectin is necessary for the implantation of blastocysts.
Animals↗
Clinical effects of local application of collagen film-immobilized tetracycline.
Tetracycline-containing cross-linked collagen film (TC film), or tetracycline-free placebo film, were locally applied 4 times, at 1-week intervals, to 33 teeth with periodontal pockets larger than 4 mm, in 11 patients with periodontal disease. The clinical and microbiological effects are summarized, as follows. In the group treated with the TC film, (1) the clinical indices were significantly decreased at the 4th and 7th weeks in comparison with those at the beginning of treatment. In particular, this group showed a significant decrease in the incidence of bleeding as compared with the placebo group at the 4th week. (2) Total counts of bacteria in the periodontal pockets showed an obvious tendency to decrease with time. The proportion of black-pigmented bacteroides was significantly decreased at the 4th and 7th weeks when compared with the pretreatment value. The extent of decrease in the proportion of spirochetes at both the 4th and 7th weeks was significant compared with the placebo group and the pretreatment value.
Bacteroides↗
Healing process of duodenal ulcers induced by indomethacin plus histamine in rats.
Healing of duodenal ulcers induced by indomethacin + histamine was investigated in rats. Animals were treated with indomethacin (5 mg/kg, s.c., once daily) and histamine (40 mg/kg, s.c., 3 times every 2.5 h after indomethacin treatment) for 2 days under fasting conditions, and they were fed normally thereafter. The duodenal ulcers so induced were confined to the proximal part of the duodenum and penetrated to the muscular mucosa with an incidence of over 80% when determined 32 h after the first injection of indomethacin (day 1). The ulcers became smaller and shallower within 7 days with granulation from the ulcer base, the mucosa grew in from the edges over the surface of granulation tissue, and they had healed almost completely after 15 days with epithelial regeneration from the edge of the ulcers. The healing of ulcers was significantly promoted by a 5-day treatment with an antacid (Al(OH)3) as well as antisecretory agents (omeprazole, cimetidine, propantheline bromide) and 16,16-dimethyl prostaglandin E2 at the dose which produced a potent inhibition of acid output and a marked increase in duodenal alkaline secretion. These results suggest that the duodenal ulcers induced in rats by indomethacin + histamine may provide a useful model for studying the healing process of duodenal ulcers and for the evaluation of the drugs with possible effects on ulcer healing.
Animals↗
Prognosis of secretory otitis media in relation to viscoelasticity of effusions in children.
Both elasticity (G') and viscosity (eta') of middle ear effusions (MEEs) were measured with an oscillating sphere magnetic rheometer and compared with continuance of fluid retention in 93 ears of 69 children with otitis media with effusion (OME). The ears were divided into four groups according to the viscoelastic properties of MEEs at the first myringotomy. Eight-four percent of the ears in group 2 were free from effusion within 4 months; the difference from the other groups was statistically significant. These results indicate that the mucociliary clearance function plays an important role in the process of recovery from OME.
Child↗
Application of chemical P450 model systems to studies on drug metabolism. I. Phencyclidine: a multi-functional model substrate.
Cytochrome P450 model and liver microsomal oxidations of drugs were compared using phencyclidine. In general, the chemical reaction systems produced many oxidation products. Besides the formation of the cyclohexane-4-hydroxyl compound (2), hydroxylation of the aromatic ring was favored in the Fenton reaction system (Fe2+ + H2O2). Formation of an m-hydroxylated product (m-5) was the main aromatic oxidation pathway in the Udenfriend reaction (Fe2+-ascorbic acid-O2), and 2, the piperidine-3-hydroxyl compound (3), and the piperidine-4-hydroxyl compound (4) were also formed. In the system using meso-tetraphenylporphinatoiron chloride (Fe(III)TPPC1) with an oxidant, the main product was the piperidine-3-oxo compound (8). In the liver microsomes system, 2, 4, 8, and m-5, which were all generated by the chemical oxidation reactions, were detected as metabolites of phencyclidine. They were formed by cytochrome P450-dependent reactions. Chemical oxidation systems can be used to study drug metabolism; they can reveal some tendencies of the real metabolic reactions, are easy to operate, and yield sufficient amounts of product.
Animals↗
Hematological studies on naturally occurring substances. II. Effects of animal crude drugs on blood coagulation and fibrinolysis systems.
The effects of 112 extracts prepared from 37 kinds of animal crude drugs and a dog's filaria were investigated on the blood coagulation and fibrinolysis systems in vitro. The plasma recalcification time method was employed for the assay of blood coagulation and fibrinolytic activity was tested by the fibrin plate method. It was found that the water extracts of Bombyx Batryticatus, Carpio Fel and Holotrichiae Vermiculus showed potent inhibitory effects on blood coagulation. The methanol extracts of Phocae Thstis et Penis, Scorpion and Tabanus were promotive effect, on the other hand. As regards the fibrinolysis system, the water extracts of Agkistrodon, Lumbricus, Hirudo, Scolopendra and Scorpion and the methanol extract of Hirudo showed a remarkable activity.
Animals↗
The complement system in the acute phase of myocardial infarction.
Although some studies suggest that complement activation is involved in the development of acute myocardial infarction, there has been little convincing evidence of a change in the complement system in patients suffering from myocardial infarction. In this study circulating levels of C3a, C3, C4 and the total hemolytic complement titer (CH50) were serially measured in 12 patients with acute myocardial infarction up to 10 days after an attack. The plasma C3a level was greatly elevated throughout the post-attack observation period. The C3, C4 and CH50 levels were significantly increased above those controls on days 8, 9 and 10 after infarction. These findings indicate that there is complement activation in patients with acute myocardial infarction, and suggest a pathogenetic role for complement activation in the development of myocardial damage after infarction.
Acute-Phase Reaction↗