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Biomedical subjects

S Ueda

Publications and source records attributed to S Ueda.

At least 1,027 records · Page 57Linked to original sources
PubMed1982

Effects of acetylcholine on the tone and miniature contractions of isolated dog urinary bladder.

Effects of acetylcholine on the tone and miniature contractions of dog urinary bladder were investigated in vitro. In both dome and trigone preparations, cumulative administrations of acetylcholine produced dose-dependent increases in the tone, which were dose-dependently depressed by prior administration of atropine and augmented by neostigmine. The frequency of miniature contractions in the dome and trigone was dose-dependently increased by acetylcholine. The dose-response curves of the frequency for acetylcholine were shifted to the right by atropine and to the left by neostigmine in both preparations. The amplitude of miniature contractions in both preparations was not significantly changed by acetylcholine. A computer analysis showed that changes in the tone of the bladder had the positive correlation to the frequency of miniature contractions. The results indicate that acetylcholine would act on the urinary bladder through activation of muscarinic receptors, and that there is the positive correlation between changes in the tone and the frequency of miniature contractions.

Acetylcholine↗
PubMed1982

Effects of adrenergic drugs on miniature contractions of isolated dog urinary bladder.

Isolated dog urinary bladder showed spontaneous miniature contractions under a steady state. In dome preparations, norepinephrine and isoproterenol decreased the frequency of miniature contractions, while epinephrine produced biphasic responses on it; increase by low concentration and decrease by high concentrations. The height of miniature contractions was decreased by these drugs. In trigone preparations, norepinephrine and epinephrine increased the frequency of miniature contractions, while isoproterenol decreased it. These drugs decreased the height of miniature contractions. In both preparations, phentolamine enhanced the decreases in frequency and height by norepinephrine, epinephrine and isoproterenol, while propranolol depressed or reversed them. A computer analysis showed positive and significant correlations between changes in tension development of bladder and frequency and height of miniature contractions. Results indicate that miniature contractions in both dome and trigone of isolated dog urinary bladder are increased by activation of alpha-adrenoceptors and decreased by activation of beta-adrenoceptors.

Animals↗
PubMed1982

An extensive primary myocardial fibrosis in progressive systemic sclerosis--a case report with autopsy findings.

An extensive myocardial fibrosis due to progressive systemic sclerosis (PSS) was described in a 36-year-old normotensive woman without pulmonary hypertension. An electrocardiogram showed low voltage and a pseudo-infarctional pattern in leads V1 through V3. Right ventricular dilatation and generalized left ventricular hypokinesis were present, but her pulmonary artery pressure was normal. Serum creatine kinase (CK) was elevated to 2305 U/L and CK-MB isoenzyme was as high as 7.1%. Simultaneously performed isoenzyme analysis of CK from the homogenate of the skeletal muscle of the patient showed a similar pattern, thus confirming that serum CK originated mainly from the skeletal muscle lesions. Autopsy findings demonstrated diffuse myocardial fibrosis and relatively unremarkable changes in the lungs and the kidneys. Our case serves as a warning that primary myocardial fibrosis could be, in some cases, so extensive that it might lead to a rapidly aggravated myocardial dysfunction and eventual death.

Adult↗
PubMed1982

Immunohistochemical studies on the processes of serotonin neurons and their ramification in the central nervous system--with regard to the possibility of the existence of Golgi's rete nervosa diffusa.

Using various vertebrates from teleost to macacus, we studied, by the modified PAP method, the serotonin neurons that are distributed mainly in the raphe nuclei area, focussing on their process ramifications, and obtained the following results. 1. The shapes of serotonin neurons were varied. They were multipolar with many long, thick dendrites. In most of the neurons, more than two axons originated either from the stem of a dendrite or from its tip. 2. The axons contained spherical or spindle-shaped varicosities of varied sizes (diameter 0.5-6 micron). On a few occasions, they became large, Herring body-like droplets. 3. The axons were classified into four groups according to the shape and size of the varicosities they contained: stem fibers, A-fibers (tract fibers), B-fibers (branching fibers) and C-fibers (ground fibers). 4. The axon not only branched frequently, but formed a true network by way of frequent anastomosis at the level of B- and C-fibers. Serotonin fibers do not have endings that correspond to telodendrons, but conduct impulses through "en passant" type synapses. 5. A supraependymal plexus is formed over large areas of the ventricular system. This vast network is considered to be formed by the syncytial continuity of axonal reticulum of many serotonin neurons. 6. Serotonin neurons, and probably noradrenaline neurons as well, should be classified as a third type of neuron, which belong to neither the Deiters type nor the Golgi type neuron. Their characteristic feature is the long, reticular axons, and it is highly probable that this neuron system forms the "rete nervosa diffusa" proposed by GOLGI.

Animals↗
PubMed1982

HB Handa [alpha 90 (FG 2) Lys replaced by Met]: structure and biosynthesis of a new slightly higher oxygen affinity variant.

Hb Handa, an abnormal hemoglobin which isoelectrofocused anodally to Hb A, was found in a 15-year-old Japanese girl and her mother, who were apparently healthy. Clinical and hematological examinations showed no abnormality in individual heterozygous for this mutant gene except for a slight increase of reticulocyte count (2.1-2.4%). Structural studies disclosed an alpha chain anomaly and substitution of alpha 90 (FG 2) Lys replaced by Met. The content of the abnormal hemoglobin in the hemolysate was 17.5-18.3% of the hemoglobin. The isopropanol precipitation test was negative. The purified abnormal hemoglobin showed a slightly higher oxygen affinity than that of Hb A, but Hill's n constant, Bohr effect and organic phosphate effect were within the normal range. Globin chain biosynthesis in reticulocytes indicated that the production rate of the abnormal alpha chain was suppressed to 38% of the normal level.

Adolescent↗
PubMed1982

The presence of glutamate mutase in a methanol-utilizing bacterium, Protaminobacter ruber.

Cell-free extracts of a facultative methylotroph and strict aerobe, Protaminobacter ruber, could catalyze formation of beta-methylaspartate from glutamate. beta-Methylaspartate formed was further converted to mesaconate. From these results, it was found that the cells of P. ruber contained a sequential reaction system of glutamate mutase and beta-methylaspartase. The level of glutamate mutase activity was almost constant throughout the period of cultivation. When P. ruber was grown on several non-one-carbon compounds in addition to methanol as a sole carbon source, the activity of glutamate mutase was not markedly affected by the kinds of carbon sources.

Amino Acid Isomerases↗
PubMed1982

Monoclonal antibodies specific to and cross-reactive with Marek's disease virus and herpesvirus of turkeys.

In order to identify the specific and cross-reactive antigens to Marek's disease virus (MDV) and herpesvirus of turkeys (HVT), we prepared hybridomas producing monoclonal antibodies against these viruses. These monoclonal antibodies were screened by the indirect immunofluorescence method. The purified virus-specific antigens appeared to be more effective immunogens than unpurified virus-infected cell homogenates. Totals of 50 and 14 hybridoma clones were found to produce antibodies specific to MDV and HVT, respectively. Of these, 14 MDV clones and 5 HVT clones produced antibodies that recognized antigenic sites common to both viruses.

Animals↗
PubMed1982

Effect of hypertension on lipid metabolism and beta-oxidation in rat aorta and brain microvessels.

The effects of hypertension on various enzyme activities involved in lipid metabolism and beta-oxidation in rat brain microvessels and aorta were studied. The purity of the brain microvessel preparation was confirmed immunologically and microscopically. Activities involved in lipid synthesis, such as triacylglycerol synthesizing activity, acyl-CoA synthesizing activity, acyl-CoA: cholesterol acyltransferase and cytidine diphosphate choline:1,2-diacylglycerol cholinephosphotransferase, were significantly higher in brain microvessels than in aorta in both normotensive and hypertensive rats; lipid hydrolyzing activities, such as lipases and cholesterol esterases, were similar in the two preparations. beta-oxidation in brain microvessels was more active than in aorta in both groups. Hypertension did not alter these enzyme activities in either aorta or brain microvessels, or change beta-oxidation in the aorta. However beta-oxidation in brain microvessels was significantly lower in hypertensive rats than in normotensive rats. These results suggest that brain microvessels are metabolically more active than aorta, and that their beta-oxidation activity is more susceptible to effects of hypertension. Reduced beta-oxidation in brain microvessels might lead to angionecrosis by derangement of energy production, which in turn may cause cerebral bleeding.

Animals↗
PubMed1982

A possible mechanism involved in generation of automaticity of isolated human renal artery.

A possible mechanism involved in generation of automaticity of isolated human renal arteries was investigated qualitatively. Helical strips of human renal arteries showed rapid contractions followed by marked oscillations in the tension by administrations of vasoconstrictor agents such as norepinephrine, epinephrine, dopamine and 5-HT. Vasodilator agents such as acetylcholine and isoproterenol did not produce any change in these strips, but high doses of acetylcholine and isoproterenol evoked marked oscillations together with increases in the vascular tone. Prostaglandins E1, E2 and F2 alpha increased the vascular tone of the renal arterial strips, and generated marked oscillations in their contractions which were inhibited by aspirin or indomethacin. Two renal arterial strips showed marked oscillations in the tension by passive elevation of the basal tone of the strips. The marked oscillations did not appear when indomethacin was previously administered. The results indicate that mechanical stimulation of renal arterial smooth muscle, such as contractions, may induce enhancement of endogenous prostaglandin biosynthesis, resulting in generation of automaticity of isolated human renal arteries.

Acetylcholine↗