Search PubMed⌕ Search

Biomedical subjects

M Oya

Publications and source records attributed to M Oya.

At least 127 records · Page 7Linked to original sources
PubMed1989

Effects of pancreastatin on insulin and pancreatic polypeptide secretion in the dog.

Porcine pancreastatin (1.19 nmol) was administered into the peripheral vein (i.v.) or the third cerebral ventricle (i.t.v.) of dogs and its effect on the secretion of insulin and pancreatic polypeptide (PP) studied. Neither means of administration had any effect on basal and glucose-induced insulin or PP secretion. However, i.v. pancreastatin did inhibit the i.v. CCK-8-induced insulin but not PP release. Pancreastatin may thus play a role in the regulation of insulin secretion in the canine pancreas.

Animals↗
PubMed1989

[Vincristine, adriamycin, mitomycin-C and UFT (VAM-UFT) therapy in progressive or recurrent breast cancer].

Since June 1984, 23 cases of progressive or recurrent breast cancers were treated with combination chemotherapy of VAM-UFT consisting of vincristine, adriamycin, mitomycin C and UFT. Clinical effects of VAM-UFT therapy were 3 CR, 12 PR, and the response rate was 65.2%. Its effective interval was 3 months. But the patients treated with over 4 cycles of VAM-UFT therapy showed an 85% response rate, with a 5-month effective interval. In each patient's background, a shorter disease free interval tended to be more highly effective, but other factors were not significant. Scirrhous carcinoma of pathology evidenced slightly high response rate. Compared with the survival time of patients treated with under 3 cycles and over 4 cycles of this therapy, the latter was significantly longer. Toxicity involved leukocytopenia (74%), thrombocytopenia (22%), anemia (30%), alopecia (91%), nausea and vomiting (87%) and stomatitis (35%), but cases in which the treatment was stopped were not observed. Therefore VAM-UFT therapy had a highly therapeutic effect, reflected in an 85% response rate, for progressive or recurrent breast cancers.

Adult↗
PubMed1989

Effects of pancreatic polypeptide on basal and meal stimulated secretion of gastrointestinal, pancreatic and adrenocortical hormones in the dog.

We have assessed the effects of intravenous infusion of bovine pancreatic polypeptide (PP) (1 microgram kg-1 h-1) on the basal and postprandial secretion of gastrointestinal, pancreatic and adrenocortical hormones in normal dogs. Bovine PP within the physiological range increased plasma cortisol levels transiently but significantly. PP elicited an inhibition of insulin response to a protein-rich meal, and tended to reduce the gastrin response. There were, however, no significant changes in basal or postprandial plasma concentrations of motilin and pancreatic glucagon during PP infusion. These results suggest that PP may have a role in controlling insulin secretion from the pancreas. The possible mechanisms are discussed mainly on the basis of vagal innervation.

Adrenal Cortex Hormones↗
PubMed1988

Proton NMR resonance assignments and surface accessibility of tryptophan residues of a dimeric phospholipase A2 from Trimeresurus flavoviridis.

Proton NMR spectra of a dimeric phospholipase A2 from Trimeresurus flavoviridis have been recorded. N-1 proton resonances of the tryptophan indole rings have been detected and assigned to specific positions, Trp-3/Trp-30, Trp-68 and Trp-108, by comparing the spectra of the enzyme derivatives with tryptophans oxidized to differing extents. Photo-CIDNP experiments have revealed that Trp-68 and Trp-108 are exposed while Trp-3 and Trp-30 are buried in the molecule. This is consistent with the X-ray crystal structure of a homologous phospholipase A2 from Crotalus atrox where residues 3 and 30 are located at a dimer interface, but inconsistent with the results of stepwise oxidation of tryptophan residues.

Macromolecular Substances↗
PubMed1988

Peptide YY receptors in the brain.

Radiolabelled ligand binding studies demonstrated that specific receptors for peptide YY are present in the porcine as well as the canine brains. Peptide YY was bound to brain tissue membranes via high-affinity (dissociation constant, 1.39 X 10(-10)M) and low-affinity (dissociation constant, 3.72 X 10(-8)M) components. The binding sites showed a high specificity for peptide YY and neuropeptide Y, but not for pancreatic polypeptide or structurally unrelated peptides. The specific activity of peptide YY binding was highest in the hippocampus, followed by the pituitary gland, the hypothalamus, and the amygdala of the porcine brain, this pattern being similarly observed in the canine brain. The results suggest that peptide YY and neuropeptide Y may regulate the function of these regions of the brain through interaction with a common receptor site.

Amygdala↗
PubMed1988

DIA3 phenotyping in human tissues, dental pulps, and hair roots by isoelectric focusing.

The polymorphism of DIA3 was investigated in tissues of various human organs, dental pulps, and hair roots by isoelectric focusing. DIA3 types were demonstrated from tissues of brain, prostate, testis, ovary, and uterus, but not from tissues of spleen, pancreas, heart, liver, muscle, lung, skin, and kidney. Determination was possible from dental pulps stored at room temperature for up to 2 weeks and from fresh hair roots. The results show that the DIA3 typing by isoelectric focusing is useful for medicolegal individualization of brain, reproductive organs, teeth, and hairs.

Dental Pulp↗
PubMed1988

Glucose phosphate isomerase variants in human bloodstains and seminal stains.

Glucose phosphate isomerase (GPI) variants occurring in human red cells were also demonstrated in human semen. Phenotyping was possible from bloodstains of 6 weeks storage and seminal stains of 12 weeks storage. The GPI system may be a supplemental tool for medicolegal individualization of seminal stains.

Blood Stains↗
PubMed1988

Novel calcium antagonists. Synthesis and structure-activity relationship studies of benzothiazoline derivatives.

A series of novel compounds having a benzothiazoline skeleton was studied for their structure-activity relationship (SAR) with respect to Ca2+ antagonistic activity. As test compounds, analogues of 3-acyl-2-arylbenzothiazolines (3) were synthesized. Benzothiazoline derivatives (3) exerted higher Ca2+ antagonistic activity than the corresponding thiazolidine derivatives (2). Effects of substituents R1-R4, the substitution position of the aminoalkoxy group and R2, and the length of the methylene chain on biological activities were examined. Compound 4 [3-acetyl-2-[5-methoxy-2-[4-[N-methyl-N-(3,4,5-trimethoxyphenethyl ) amino]butoxy]phenyl]benzothiazoline hydrochloride] showed a potent Ca2+ antagonistic activity in vitro and dual inhibition on the fast Na+ inward channel and the slow Ca2+ inward channel in Langendorff perfused rabbit hearts. Compound 4 also showed a long-acting hypotensive effect in spontaneously hypertensive rats and prevented acute pulmonary thrombotic death in mice.

Animals↗
PubMed1987

Proglumide has access to brain and antagonizes the central satiety effect of cholecystokinin octapeptide in the dog.

Intra-third cerebroventricularly administered cholecystokinin octapeptide (CCK-8) decreased food intake through central mechanisms in the dog. Proglumide, administered intravenously, did enter into cerebrospinal (ventricular) fluid, and partially, but significantly, reversed this effect. CR1409, one of the newly synthesized glutaramic derivatives, blocked CCK-8-induced satiety more strongly than proglumide. These results indicate that systemic proglumide and CR1409 result in antagonism of the central CCK receptor for satiety in the dog.

Animals↗
PubMed1987

Role of C-terminal tail of long neurotoxins from snake venoms in molecular conformation and acetylcholine receptor binding: proton nuclear magnetic resonance and competition binding studies.

The role of the "C-terminal tail" segment of long neurotoxins has been investigated. The C-terminal four to five residues of alpha-bungarotoxin and Laticauda colubrina b have been cleaved off by carboxypeptidase P. The effect of such deletion on the toxin conformation has been monitored in proton nuclear magnetic resonance spectra and circular dichroism spectra. The removal of the C-terminal residues primarily affects the chemical shifts of proton resonances of the residues close to the cleavage site and does not induce a major conformational change. Therefore, the C-terminal tail of long neurotoxins does not appear to be important in maintaining the specific polypeptide chain folding. On the other hand, competition binding with tritium-labeled toxin alpha to Narke japonica acetylcholine receptor has revealed that cleavage of the C-terminal residues reduces the binding activity of alpha-bungarotoxin or Laticauda colubrina b to acetylcholine receptor. Thus it is likely that (the basic amino acid residues in) the C-terminal tail is directly involved in the binding of long neurotoxins to electric organ (and muscle) acetylcholine receptor.

Amino Acid Sequence↗
PubMed1987

DIA3 phenotyping in human semen and seminal stains by isoelectric focusing.

The polymorphism of DIA3 was investigated by isoelectric focusing in semen samples from 235 unrelated Japanese volunteers and patients. Besides the three common phenotypes seven samples of the type 3-1 were observed. However, readable isoenzyme patterns were not demonstrated in semen samples of oligospermia under about 10 X 10(6)/ml sperm cells. The allele frequencies were DIA3*1 = 0.821, DIA3*2 = 0.164, and DIA3*3 = 0.015. The DIA3*1 frequency in oligospermia (0.765) was lower than that in normospermia (0.836). The isoelectric focusing method was successfully applied to phenotyping DIA3 in seminal stains; each phenotype was demonstrated at 37 degrees C for up to 4 weeks, at room temperature for up to 8 weeks, and at 4 degrees C for over 12 weeks after stain formation. In vaginal swabs the isoenzyme bands were very faint and not identifiable.

Dihydrolipoamide Dehydrogenase↗
PubMed1987

alpha-L-fucosidase phenotyping in human tissues, dental pulps and hair roots.

Phenotypes of alpha-L-fucosidase (Fu) were demonstrated from tissue samples of spleen, liver, lung and kidney stored for a few weeks at room temperature. Activity was fairly low in pancreas, heart, muscle, skin and brain, and typing was not reliable after 1 week storage. Fu types were detectable from dental pulp tissue of up to 1 week storage. Activity was present in hair root cells, but was extremely low. The results show that the Fu typing may be applicable to individual identification of organ tissues and teeth.

Dental Pulp↗