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Biomedical subjects

Y Abe

Publications and source records attributed to Y Abe.

At least 739 records · Page 41Linked to original sources
PubMed1991

Improvement of postischemic contractile dysfunction of dog heart by MCI-154, a novel cardiotonic agent.

The effects of MCI-154, a cardiotonic agent which has direct effects on cardiac myofilaments, on postischemic contractile dysfunction were studied in dog heart subjected to a 30-min occlusion of the left anterior descending coronary artery followed by reperfusion, and compared with the effects of milrinone and dobutamine, that have largely cyclic AMP-dependent mechanisms of action. Regional myocardial contractility (segment shortening) and tissue ATP levels were severely depressed in reperfused myocardium. MCI-154 (0.3 and 1 microgram/kg per min) improved the regional function of postischemic myocardium and decreased left ventricular end-diastolic pressure and systemic aortic pressure when infused i.v. from 30 min after reperfusion. The improvement of regional function caused by MCI-154 (1 microgram/kg per min) was more pronounced than that caused by milrinone (1 microgram/kg per min) or dobutamine (1 microgram/kg per min), although the drugs produced an equal increase in cardiac performance (peak positive left ventricular dP/dt). These results suggest that MCI-154 produces a more pronounced improvement of regional myocardial function than milrinone and dobutamine, presumably by increasing the responses of the contractile protein system to Ca2+. In this respect, MCI-154 would be of much benefit for the treatment of postischemic left ventricular dysfunction.

Adenosine Triphosphate↗
PubMed1991

Decreased urinary epidermal growth factor levels in diabetic patients.

Urinary human epidermal growth factor levels were assayed in diabetic patients and controls before and after surgery. The preoperative levels in the diabetic patients were decreased and postoperatively, did not show the trough and peak pattern which was seen in the controls.

Diabetes Mellitus, Type 2↗
PubMed1991

The accelerated repopulation of a murine fibrosarcoma, FSA-II, during the fractionated irradiation and the linear-quadratic model.

Radiation response of a spontaneous mouse fibrosarcoma, FSa-II, to various fractionated doses was studied in vivo together with single dose cell survival curves. Early generation isotransplants were used. Animals were C3Hf/Sed mice derived from our defined flora mouse colony. Lung colony and TD50 assays were used to determine cell survival. Surviving fractions were determined following fractionated irradiations of 1.0 to 5.0 Gy each per fraction with interfractional time intervals of 4 hr. The alpha/beta ratio based on fractionated irradiations was 8.8 Gy for aerobic FSa-II tumor cells and flexure dose was less than 1.3 Gy. Multiple fractions of 5.0 Gy each given with 4, 12, and 24 hr intervals showed an increase in survival with increasing interfractional time interval, suggesting a rapid repopulation of tumor cells between fractions; namely, cell doubling time was shortened between fractions after the first 5.0 Gy doses. These results indicated that tumor cell repopulation is a critical factor in the fractionated radiotherapy. Linear-quadratic model was fitted to single dose survival data. Single dose survival curve of aerobic FSa-II tumor cells following lung colony assays which allowed determination of minimal survival of approximately 3.0 x 10(-3) showed that alpha, beta, and alpha/beta ratios were 0.25 Gy-1, 0.048 Gy-2, and 8.47 Gy, respectively. Single dose survival curve of the same aerobic cells determined by both lung colony and TD50 assays to a survival level of approximately 3.0 x 10(-6) demonstrated that alpha, beta, and alpha/beta ratios were 0.375, 0.0127, and 29.5, respectively. Similar determination for hypoxic FSa-II tumor cells showed that alpha, beta values were smaller whereas the alpha/beta ratio was much larger than for aerobic cells. The oxygen enhancement ratio calculated by the alpha/beta ratios was greater than 3.0.

Animals↗
PubMed1991

Preparation and properties of a lysozyme derivative in which two domains are cross-linked intramolecularly between Trp62 and Asp101.

A lysozyme derivative in which two domains were cross-linked intramolecularly was newly prepared by means of a two-step reaction. First, the beta-carboxyl group of Asp101 in lysozyme was selectively modified with 2-(2-pyridyldithio)ethylamine in the presence of 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide hydrochloride. After reduction of the pyridyldithio moiety of Asp101 modified lysozyme at pH 4.5 with dithiothreitol, the derivative was allowed to cross-link intramolecularly by reaction with 1,3-dichloroacetone at pH 7. Intramolecularly cross-linked lysozyme thus formed was purified by gel chromatography followed by ion-exchange chromatography. Based on the results of 1H-NMR and peptide analyses, it was concluded that Asp101 was cross-linked to Trp62 with a -CH2COCH2SCH2CH2NH-bridge in this derivative. The derivative showed minor but distinct activity against Micrococcus lysodeikticus and glycol chitin. Its melting temperature for thermal denaturation was higher by 7.3 degrees than that of native lysozyme at pH 3.

Amino Acid Sequence↗
PubMed1991

Measurement of plasma total renin by the anti-human renin monoclonal antibodies.

The authors evaluated the assay performances and clinical usefulness of a newly developed solid phase radioimmunoassay (RIA) for total renin concentration (TRC) in human plasma. The direct total renin RIA was performed by a sandwich technique with a pair of anti-human renin monoclonal antibodies. Renin activation with trypsin did not change TRC. The RIA showed satisfactory assay performances and demonstrated full compatibility with a direct RIA-kit for active renin concentration (ARC) in human plasma. The values of TRC were 105.3 +/- 8.6 pg/mL in normal subjects and 136.5 +/- 14.6 pg/mL in patients with essential hypertension. The values of TRC and the ratios of ARC to TRC were high in patients with renovascular hypertension and were low in patients with primary aldosteronism. Although the TRC value in diabetic patients was 134.4 +/- 14.8 pg/mL, the ratio of ARC to TRC was low. The RIA procedure was simple since prior purification or activation of renin was not required. These results suggest that the total renin RIA and its combined use with the active renin RIA may be helpful in understanding the renin-angiotensin system in human plasma.

Antibodies, Monoclonal↗
PubMed1991

Effects of cromakalim on renal hemodynamics and function in dogs: comparison with nicardipine.

The effects of cromakalin, a potassium channel opener, on renal hemodynamics and renal function were investigated in pentobarbital-anesthetized dogs. Intrarenal infusion of cromakalim at 0.5 micrograms/kg/min resulted in significant increases in renal blood flow (RBF), glomerular filtration rate (GFR), urine flow, and renin release. The urinary excretion rate of sodium increased by the same proportion as that of calcium. Free water reabsorption rate/osmolar clearance did not significantly change throughout the experiments. These data suggest that cromakalim did not inhibit sodium transport at the medullary portion of the ascending limb of Henle's loop and may have increased the delivery of sodium to Henle's loop. Intrarenal infusion of nicardipine increased RBF, GFR, urine flow, and the urinary excretion of electrolytes (Na, K, and Ca). The renal effects of cromakalim were very similar to those of nicardipine. Cromakalim was superimposed on a nicardipine infusion of a maximal effective dose. Superimposition of cromakalim to the nicardipine infusion did not cause any additional changes in renal hemodynamics and renal function. These data suggest that cromakalim and nicardipine exert their effects on renal hemodynamics and function via the same pathway.

Animals↗
PubMed1991

Trigeminal trophic syndrome--a report of three patients.

Three Japanese patients with trigeminal trophic syndrome, a rare dermatosis in Japan, were reported. Cutaneous lesions were a long-standing ulcer and destruction of the right ala nasi in case 1, a persistent deep ulceration on the forehead after a small trauma in case 2, and development of small, discrete ulcers on the right forehead during the treatment of a postherpetic neuralgia in case 3. A protective device was very effective in one patient.

Aged↗
PubMed1991

Expression of membrane-associated lymphotoxin/tumor necrosis factor-beta on human lymphokine-activated killer cells.

A membrane-associated lymphotoxin (LT)-related molecule was detected on human lymphokine-activated killer (LAK) cells by flow cytometric analysis. Kinetic analysis revealed that the LT antigenicity on LAK cells appeared at 9 h after the beginning of culture and was maintained thereafter. By autoradiography, the molecular weight of membrane LT was estimated to be 31 kD and/or 62 kD.

Cell Membrane↗
PubMed1991

Phenotyping of peripheral blood hemopoietic progenitor cells--in vitro cultures using CD34-/CD33-immunomagnetic purging.

In contrast to many detailed studies on the antigenic profile of hemopoietic progenitor cells from human bone marrow, sparse information, so far, has been gathered with regard to the antigen expression of hemopoietic progenitors present in peripheral blood. Previous studies by multiparameter flow-cytometry have revealed substantial differences of the coexpression of the CD33-, CD19-, and CD74- antigens, respectively, on CD34-positive cells from blood versus those from bone marrow, respectively. Immunomagnetic purging with monoclonal antibodies detecting the CD34-, and the CD33- antigen, respectively, has been used to further characterize the expression of these antigens on day 8 and d-14 granulocyte/macrophage and erythroid colonies as grown from circulating progenitor cells. Purging with CD34 monoclonal antibody abrogated all colony formation, whereas purging with CD33 antibody led to differential inhibition of the various progenitors. Purging bone marrow cells with CD34 antibody, an inhibition of only about 25% was observed with regard to erythroid colonies, whereas an inhibition of about 85% was observed for CFU-GM. These findings reinforce the view that circulating progenitor cells represent relatively immature stages of differentiation, when compared to bone marrow progenitors. Particularly, d-8 erythroid colonies from blood do not represent the equivalent of the genuine CFU-E as described from bone marrow, but they seem to be early stages of BFU-E development.

Adult↗
PubMed1991

Effect of hemodialysis on the concentration of the seven tumor markers carcinoembryonic antigen, alpha-fetoprotein, squamous cell carcinoma-related antigen, neuron-specific enolase, CA 125, CA 19-9 and CA 15-3 in uremic patients.

The incidence of the 7 tumor markers carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), squamous cell carcinoma-related antigen (SCC), neuron-specific enolase (NSE), CA 125, CA 19-9 and CA 15-3 was studied before and after hemodialysis (HD) in 144 uremic patients who had no malignancies. Before HD, of all tumor markers, the mean concentration of SCC only exceeded the normal value. The positive rate was highest in SCC (95.1%), and that of CEA and NSE was 25.7 and 10.6%, respectively. However, AFP was within the normal range in all cases. Among CA antigens, the positive rate of CA 125 was 7.6%, of CA 19-9 was 6.3% and of CA 15-3 was 3.5%. After HD, the incidence as well as the mean concentration of all tumor markers increased. A parallel increment of total protein was observed after HD. The membrane filter used in HD appears to be insufficient to remove tumor marker proteins during HD. It is necessary to consider the clinical interpretation of elevated tumor markers in patients with uremia.

Antigens, Neoplasm↗
PubMed1991

Effects of prolonged treatment with beta-adrenoceptor antagonist, carteolol on systemic and regional hemodynamics in stroke-prone spontaneously hypertensive rats.

The present study was designed to determine the regional hemodynamic effects of prolonged beta-adrenergic receptor inhibition in conscious stroke-prone spontaneously hypertensive rats (SHRSP) using a radioactive microsphere method. When the regional blood flow was compared between 10 and 30 weeks of age, the age-related changes in organ blood flow were observed in several organs, i.e., the reduction of flow rate in kidney, adrenal gland and intestines. The reduction of flow rate in these organs contributes strongly to the age-related rise of total peripheral resistance. Carteolol, a beta-adrenoceptor antagonist, was given at a dose of 10 mg/kg/d from 10 to 30 weeks of age. These animals gained more weight than the untreated control SHRSPs, and heart rate was reduced significantly. Blood pressure was not affected. However, the prolonged treatment with carteolol prevented the age-related reduction of the blood flow rate in the kidney, adrenal gland and intestines. Thus, our findings indicate that carteolol had appreciable and beneficial effects on the maintenance of flow rates in the above organs of SHRSP without any change in blood pressure.

Animals↗
PubMed1991

[Expression of the renin and angiotensinogen genes].

Recent advances in molecular biological techniques provide us with genetic approaches for studying the renin-angiotensin system. Renin and angiotensinogen cDNAs have been cloned in several species, and the sequences are highly conserved between the species. The 5'-flanking region of the human renin gene indicated putative regulatory sequences of glucocorticoid, estrogen, progesterone, and cAMP. The 5'-flanking region of the human angiotensinogen gene also had putative regulatory sequences of glucocorticoid, estrogen, acute phase protein, and cAMP. These structures may be related to the tissue specific expression of the renin and angiotensinogen genes. In this review, expression of rat renin and angiotensinogen genes in various tissues in the following conditions are described: a) different sodium intake in the liver, kidney, and brain; b) angiotensin II and converting enzyme inhibition in the liver, kidney and brain; c) renovascular hypertension in the kidney and liver; d) aging in the liver and kidney; e) adrenal steroids in the liver, kidney and brain; f) gonadotropin and testosterone in the testes, liver and kidney; g) triiodothyronine in the liver, kidney and brain; h) nephrectomy in the liver and brain; i) high potassium, angiotensin II, sodium intake and nephrectomy in the adrenal gland; j) transgenic animal. Our results suggest that the expression of the renin and angiotensinogen genes are regulated in a tissue-specific manner.

Aging↗
PubMed1991

Forskolin preferentially dilates the afferent arteriole in the canine kidney.

Intrarenal infusion of forskolin (0.2 microgram/kg/min) in anesthetized dogs increased renal blood flow (RBF) and glomerular filtration rate (GFR) to the same degree but did not change the mean arterial pressure or heart rate. Forskolin also increased urine flow and urinary sodium excretion. The proportional increases in RBF and GFR may result from a preferential action of forskolin to dilate the afferent arteriole.

Adenylyl Cyclases↗
PubMed1991

Endothelin-1-induced phosphorylation of the 20-kDa myosin light chain and caldesmon in porcine coronary artery smooth muscle.

Endothelin-1 (ET), a potent vasoconstrictor, induces a sustained increase in the phosphorylation level of the 20-kDa myosin light chain (MLC) in porcine coronary artery strips. ET also induces late phosphorylation of caldesmon, which is mimicked by 12-deoxyphorbol 13-isobutyrate, but not by 60 mM KCl. Nitroglycerin, a vasorelaxant, completely reverses the ET-induced phosphorylation of MLC, but not that of caldesmon. These results suggest an important regulatory role of MLC phosphorylation in ET-induced contraction.

Animals↗
PubMed1991

Effects of water deprivation and morphine administration on atrial natriuretic peptide mRNA levels in rat auricles.

We investigated the influences of two potent stimuli, water deprivation (5 days) and morphine administration (100 mg/kg), on the level of atrial natriuretic peptide (ANP) mRNA in the rat auricles. The ANP mRNA level was measured by Northern blot hybridization analysis. The plasma concentration of ANP decreased in water deprived rats, and the ANP mRNA levels in both auricles of these rats were lower than those of the control, particularly in the left auricle. Thirty minutes after the injection of morphine, the plasma concentration of ANP markedly increased, while morphine increased the right auricular ANP mRNA level 4 hr after the administration. These data suggest that these stimuli can change ANP gene expression in the auricles and that the changes are induced differentially in both auricles.

Animals↗