PubMed Health⌕ Search

Biomedical subjects

T Hirose

Publications and source records attributed to T Hirose.

At least 811 records · Page 45Linked to original sources
PubMed1981

Increased alveolar-capillary membrane permeability by monocrotaline.

To study the effect of monocrotaline on the pulmonary alveolar-capillary membrane permeability, cardiac catheterization, extravascular lung water content and absorption of 14C-compounds from the rat lungs in combination with morphological observations were studied in the early stage of monocrotaline intoxications. Purified monocrotaline or its pyrrole was administered to rats with various doses. Single dose of 50 mg/kg of monocrotaline was enough to induce pulmonary hypertension 4 weeks later, but neither immediate nor direct pressor effect was observed by monocrotaline or active pyrrole. Only 3 to 5 mg/kg of pyrrole was enough to produce alveolar flooding with increased extravascular lung water content and accelerated absorption of 14C-mannitol and 14C-inulin from lungs 24 hours after administration. In contrast with fast and potent effect of pyrrole, effect of monocrotaline was mild and delayed in development. These findings suggested that monocrotaline increased the porosity of not only endothelial but also alveolar membrane by active metabolite.

Animals↗
PubMed1981

Adrenal secretion of aldosterone in response to anaphylactic shock in hypophysectomized-nephrectomized dogs.

The adrenal secretion of aldosterone in response to anaphylactic shock was examined in intact and hypophysectomized-nephrectomized dogs which had been sensitized by horse serum injections (s.c. and i.v.) 24-30 days before the experiment. On the day of the experiment, dogs were injected intravenously with horse serum under pentobarbital anesthesia. During anaphylactic shock induced by horse serum, the adrenal secretion of aldosterone in intact and hypophysectomized-nephrectomized dogs increased from 1.32 +/- 0.55 (mean +/- S.E.M.) to 8.43 +/- 1.99 ng/(kg.min) and from 0.23 +/- 0.10 to 2.38 +/- 0.63 ng/(kg.min), respectively. Plasma potassium concentration increased slightly and plasma sodium concentration did not change after the injection of horse serum in hypophysectomized-nephrectomized dogs. The results suggest the possibility that the adrenal secretion of aldosterone in response to anaphylactic shock in hypophysectomized-nephrectomized dogs is due mainly to a direct effect of histamine on the adrenal cortex or occurs via some unknown factors, and only in a small part to an increase in plasma potassium concentration. The adrenal secretion of corticosterone and cortisol during anaphylactic shock increased slightly but significantly in hypophysectomized-nephrectomized dogs, whereas it increased markedly in intact dogs.

Adrenal Glands↗
PubMed1981

Direct stimulatory effect of histamine on aldosterone secretion of the perfused dog adrenal gland.

The left adrenal gland of the hypophysectomized-nephrectomized dog was perfused in situ with the blood from the femoral artery of the hypophysectomized-nephrectomized donor dog. After infusion of histamine (0.1 mg/min for 5 min) into the arterial inflow circuit, the rates of secretion of aldosterone, corticosterone and cortisol (ng/100 mg adrenal wt. each min) increased from the basal level of 0.66+/-0.21 (mean+/-S.E.M.) to 2.24+/-0.45 at 10 min, from 4+/-1 to 20+/-4 at 5 min and from 19+/-5 to 64+/-15 at 5 min, respectively. The maximal increments above the basal value after the infusion of histamine in the secretory rates of aldosterone, corticosterone and cortisol were 51, 16, and 13% that of the respective steroid after the infusion of ACTH (20mIU/min for 5 min). The results indicate that histamine has a direct stimulatory effect on the secretion of aldosterone by the adrenal gland as well as on that of corticosterone and cortisol.

Adrenal Glands↗
PubMed1981

Direct effect of histamine on the production of adrenocortical hormone by guinea-pig adrenal cells.

In trypsin-dispersed adrenal cells of the guinea-pig, the production of 11-hydroxycorticosteroids in vitro was found to be significantly stimulated by 10(-7) -10(-4)M histamine and the maximum steroidogenic response (1.7-fold increase in 11-hydroxycorticosteroid production) was observed at 10(-6)M. The stimulatory action of histamine on steroidogenesis was blocked by cycloheximide treatment.

11-Hydroxycorticosteroids↗
PubMed1981

Diagnosis and operative treatment for the brachial plexus injury.

It is shown that the electrophysiological diagnosis of brachial plexus injury is becoming more precise than ever. The intraoperative use of electrodiagnosis especially aids the obtaining of better results for brachial plexus injuries. When nerve transfer is undertaken, biceps function is more usefully restored by the accessory nerve than by the intercostal nerves. Protective sensation was achieved in almost all cases by intercostal nerve transfer. When nerve grafting was undertaken, functional motor restoration was regained in the upper arm muscles in one case, but not in the forearm.

Action Potentials↗
PubMed1981

Simulated double Bjerrum's scotomas by retinal pigment epithelium and receptor degeneration.

A seemingly glaucomatous double Bjerrum's nerve fiber bundle defect was mimicked by pigment epithelium and receptor degeneration. The discrepancy between normal appearance of the disc and the abnormal visual field was a clue indicating need for further evaluation for retinal disease unrelated to glaucoma. Ophthalmologists should be aware of the possibility of this cause of double Bjerrum's or ring scotoma to avoid protracted workup for nonexistent neurologic disease or treatment of glaucoma.

Diagnosis, Differential↗
PubMed1980

Electrocardiographic and echocardiographic findings in four cases of bovine endocarditis.

Surface limb lead electrocardiograms were recorded in four cases of endocarditis in dairy cows in which the clinical diagnosis was suggested by echocardiography, then later confirmed at necropsy. The electrocardiographic findings common to all cases were sinus tachycardia, right axis deviation (between -178 and -137 degrees); and a QRS complex of a QS variety, with an averae amplitude of -0.7 mV and a mean duration of 0.06 second in lead II. These findings were not diagnostic of endocarditis.

Animals↗
PubMed1980

Retinal detachment following congenital cataract surgery. I. Preoperative findings in 114 eyes.

One hundred fourteen eyes of patients with retinal detachment occurring after congenital cataract surgery were studied. Retinal detachment was typified by high incidences of men, myopia, preference for the second and fourth decades of life, and a fairly long interval after cataract surgery. Frequently found were the following: (1) undetected retinal breaks, (2) high incidences of small oval or round holes in the upper nasal quadrant near the ora serrata, (3) retinal detachment in more than one quadrant, and (4) extensive vitreous and preretinal traction. Preoperative examination was often hampered by a small, bound-down pupil, nystagmus, extreme photophobia, and an inability to move the eye in desired directions. The major factor in the pathogenesis of retinal detachment after congenital cataract surgery appears to be chronic vitreoretinal traction in the anterior vitreous caused by cataract removal.

Adolescent↗
PubMed1980

Membrane biophysics of chemoreception and taxis in the plasmodium of Physarum polycephalum.

The threshold phenomena observed in chemoreception and taxis of the plasmodium of Physarum polycephalum were analyzed on the basis of physical chemistry. Various physicochemical concepts and rules, e.g. the Schulze-Hardy rule, the lyotropic number and the hydrophobic interactions, were shown to be applicable reasonably well to the physiological functions in Physarum. It was stressed that the structural change of the surface membrane induced by reception of chemical stimuli plays a decisive role in recognition and sensitivity to the external stimuli as well as the appearance of tactic movement in the amoeboid motility of Physarum.

Journal Article↗
PubMed1980

Scintigraphic sequelae of superior vena caval obstruction.

The scintigraphic characteristics of superior vena caval obstruction are presented together with a discussion of the relevant vascular anatomy. Alterations in scintigraphic venous blood flow patterns of a patient who underwent two surgical bypass procedures for symptomatic relief of superior vena caval obstruction are shown.

Blood Circulation↗
PubMed1980

Pharmacokinetics of ceftizoxime in animals after parenteral dosing.

The pharmacokinetic profile of ceftizoxime was studied in mice, rats, dogs, and monkeys given the drug in a single parenteral dose. The serum data after an intravenous injection were analyzed by the two-compartment open model. Cefotiam, cefmetazole, cefotaxime, and cefamandole were used as reference drugs. High concentrations of ceftizoxime were attained in the sera of all test animals and in the tissues of rats after parenteral dosing. The serum concentrations of ceftizoxime were higher than those of the other antibiotics in large animals (dogs and monkeys), but were lower in small animals (mice and rats). About 80% of ceftizoxime was excreted unchanged in the 24-h urine of all species tested. The biliary excretion of ceftizoxime was low: 3.7% in rats and 0.59% in dogs. However, therapeutically significant concentrations of ceftizoxime were found in the bile of dogs. Ceftizoxime was stable in biological fluids such as serum, urine, and tissue homogenates, but cefotaxime was unstable in rat tissue homogenates. Binding of ceftizoxime to serum protein in all species was the lowest of all the antibiotics: 31% for humans, 17% for dogs, and 32% for rats.

Animals↗
PubMed1980

New in vitro kinetic model for evaluating bactericidal efficacy of antibiotics.

A new in vitro model was devised for evaluating the bactericidal activity of antibiotics under dynamic conditions. This model accurately reproduced the observed serum levels of antibiotics after intravenous dosing. The apparatus consists of two vessels which correspond to the central and peripheral compartments of a two-compartment open model. The volume of medium in each vessel and flow rates of media were determined from the pharmacokinetic parameters calculated from the observed serum levels selected for simulation. The bactericidal activity of cefazolin against strains of Escherichia coli and Klebsiella pneumoniae showing different minimal inhibitory concentrations was investigated with the apparatus simulating serum levels after intravenous injection, and the bactericidal activity was evaluated with respect to the relationship between the minimal inhibitory concentration and the serum levels.

Anti-Bacterial Agents↗
PubMed1980

Effects of long-term ozone exposure and dietary vitamin E in rats.

Rats fed on a vitamin E-deficient diet (E-depleted group) and a vitamin E-supplemented diet (E-supplemented group) were exposed to 0.3 ppm ozone for three hours daily, five days a week for seven months. Then animals from each group were sacrificed, and electron microscopic studies on the lung and biochemical examinations on the lung and liver were performed. 1) Vitamin E concentration in serum decreased following ozone exposure in the E-supplemented group, whereas it remained unaffected the E-depleted group. 2) Both TAB value and % release of lysosomal enzyme (acid phosphatase) of the liver were increased in vitamin E-depleted air-exposed rats, and showed even higher values following ozone exposure. Levels of both components were highest in the vitamin E-depleted ozone-exposed rats, thus demonstrating that there are a marked increase in lipid peroxide and the increased labilization of lysosomes in this instance. 3) Arachidonic acid (20:4) of total lipid, phospholipid and lecithin in the lung tissue showed a tendency to decrease in vitamin E-depleted air-exposed rats. Those in the ozone-exposed animals showed in both groups a tendency to increase in total lipid and lecithin, and to decrease in phospholipid. However, a change in the fatty acid composition following ozone exposure was generally mild. 4) The fatty acid composition of phospholipid in lung washings did not show a remarkable change following ozone exposure in either group, thus suggesting that it has the resistivity to oxidation. 5) Morphological observations on the lung with the scanning and transmission electron microscopes did not reveal any clear differences between the two groups. The defensive effect of vitamin E on ozone toxicity induced by long-term exposure to ozone was not made clear by the morphological or biochemical examination of the lung. However, biochemical findings in liver of rats exposed to ozone suggested the possibility that vitamin E deficiency permits the damaging effects of lipid peroxidation on biological membranes.

Animals↗