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Biomedical subjects

M Asano

Publications and source records attributed to M Asano.

At least 487 records · Page 27Linked to original sources
PubMed1984

Amosulalol, a combined alpha and beta adrenoceptor antagonist: kinetics after intravenous and oral doses.

Amosulalol kinetic studies were conducted in seven subjects who received 0.16 mg/kg iv and in 18 subjects who received 12.5, 25, 50, 100, or 150 mg by mouth. Plasma levels of amosulalol after intravenous dosing declined biphasically and fitted a two-compartment model. Kinetics were as follows: coefficients A = 0.85 +/- 0.09 microgram/ml and B = 0.22 +/- 0.01 microgram/ml; rate constants alpha = 2.78 +/- 0.24 hr-1 and beta = 0.25 +/- 0.01 hr-1; elimination rate constants, k12 = 1.36 +/- 0.17 hr-1, k21 = 0.78 +/- 0.06 hr-1, and kel = 0.88 +/- 0.06 hr-1; terminal phase volume of distribution = 0.75 +/- 0.06 l/kg; clearance = 8.09 +/- 0.54 l/hr; AUC = 1.22 +/- 0.09 microgram . hr/ml; and t1/2 alpha = 0.26 +/- 0.02 hr and t1/2 beta = 2.8 +/- 0.1 hr. After single oral doses, amosulalol peak plasma levels were generally reached within 2 to 4 hr. Maximum plasma concentrations and AUC increased in a dose-dependent manner, whereas t1/2 were about 5 hr (range 4.4 to 5.7 hr) at each dose. Systemic availability of amosulalol was about 100% as determined by the ratio of AUC after oral and intravenous dosing. These results suggest that amosulalol is well absorbed and is little affected by first-pass metabolism.

Administration, Oral↗
PubMed1984

Contractile responses of mammalian cerebral arteries to 15-hydroperoxyarachidonic acid vary in the presence of fusaric acid and verapamil.

The effects of fusaric acid and verapamil on 15-hydroperoxyarachidonic acid (15-HPAA)-induced cerebral arterial contraction were examined. Addition to the tissue bath of 15-HPAA in concentrations ranging from 1 X 10(-7) to 3 X 10(-5) M caused a dose-dependent contraction in canine basilar, middle cerebral, posterior cerebral and human basilar or middle cerebral arteries. Fusaric acid and verapamil antagonized the 15-HPAA-induced contraction of these cerebral arteries by different mechanisms, in a dose-dependent manner. In the presence of 1 X 10(-3) M fusaric acid, the dose-response curves of cerebral arteries for 15-HPAA were antagonized in a noncompetitive manner. However, the responses to 15-HPAA were restored completely after removal of fusaric acid from the bathing solution. Fusaric acid did not antagonize the CaCl2-induced contraction. The concentration of verapamil which antagonized the 15-HPAA-induced contraction was a good fit to the concentration of this antagonist which antagonized the CaCl2-induced contraction. These findings indicate that the antagonism seen with fusaric acid manifests as a block of the sites specific for 15-HPAA and that the antagonistic actions of verapamil on 15-HPAA may be produced by the inhibition of calcium influx.

Adult↗
PubMed1984

Gamma-aminobutyric acid-induced contraction of the dog basilar artery.

gamma-Aminobutyric acid (GABA) produced a biphasic action, that is, a relaxation followed by a contraction in the isolated dog basilar artery. Repeated applications of each concentration of GABA (10(-6), 10(-5), 10(-4), 10(-3) M) at regular intervals under resting conditions caused a stepwise increase in the contractile response. Marked reproducible contractile responses occurred (ED50: 1.3 X 10(-5) M), after at least 8-10 applications. The GABA-induced contraction as well as relaxation was blocked by bicuculline and picrotoxin. Pretreatment with inhibitors of prostaglandin synthesis such as aspirin (3 X 10(-6) to 3 X 10(-4) M) and indomethacin (3 X 10(-6) M) reduced the contractile response to GABA in an irreversible manner and without affecting the relaxation induced by GABA. These inhibitors increased the resting tone but reduced the tone in strips subjected to repeated applications of GABA. 15-Hydroperoxyarachidonic acid at concentrations of 1 X 10(-6) and 1 X 10(-5) M also attenuated the contractile response to GABA in a dose-dependent fashion. These observations suggest that GABA may modulate the contractile effect by inducing the production of contraction-causing prostaglandin(s) mediated through GABA receptors and/or by some as yet undefined mechanism.

Animals↗
PubMed1984

New protein inhibitors of cysteine proteinases in human saliva and salivary glands.

New protein inhibitors of cysteine proteinases were found in human saliva and salivary glands. The inhibitory potency present in saliva against ficin is about 30% of that in serum: 1 ml of saliva gives 100% inhibition of 1 nmol of ficin. The same amount of saliva causes no inhibition of 1 nmol of trypsin. The salivary inhibitors occur as multiple forms with different isoelectric points (pI of 4.5-4.7, 5.8, 6.8, 7.8 and 8.2) and different molecular masses of approximately 16, 11, 10, 9.5 and 9 kDa. The inhibitor forms having molecular masses of less than 11 kDa have not yet been described by other authors. The salivary inhibitors have a high thermal stability and a high stability both in alkaline and acidic solutions.

Cysteine Proteinase Inhibitors↗
PubMed1984

Hemodynamic effects of arotinolol in anesthetized dogs and its affinities for adrenoceptors in vitro.

Hemodynamic actions of arotinolol in anesthetized dogs and its effects on alpha- and beta-adrenoceptors were examined. Arotinolol produced dose-dependent decrease in mean blood pressure, heart rate, cardiac output, maximum rate of left ventricular pressure rise and coronary blood flow in a dose range of 1 microgram/kg-3 mg/kg. Total peripheral resistance (TPR) increased with arotinolol dose-dependently in a dose range of 1 microgram/kg-0.3 mg/kg, but at doses of 1 and 3 mg/kg the increase in TPR was less. Arotinolol at a dose of 10 micrograms/kg significantly inhibited the blood pressure and heart rate responses to isoproterenol. Propranolol at the same dose produced only a slight inhibition of these. Arotinolol at a dose of 3 mg/kg attenuated the pressor response to phenylephrine without any effect on the response to angiotensin-II in anesthetized dogs. Propranolol at the same dose produced only a slight inhibition of the response to phenylephrine. In the study of radioactive ligand binding assays, arotinolol showed high affinities for both beta 1- and beta 2-adrenoceptors. Arotinolol showed an affinity also for alpha 1-adrenoceptors which was comparable to the affinity of yohimbine. Thus, the present results support the idea that arotinolol possesses both alpha- and beta-adrenoceptors blocking effects.

Adrenergic beta-Antagonists↗
PubMed1984

[Comparative study on intravenous drip infusion of dibekacin once daily and twice daily in treatment of complicated urinary tract infections].

Dibekacin (DKB) was administered to patients with complicated urinary tract infections without any indwelling catheter to evaluate objectively and comparatively the efficacy, safety and usefulness of intravenous drip infusion once daily and twice daily in a well-controlled study. A 50 mg dose of DKB was administered twice a day to group A, and a 100 mg dose was given once a day to group B. In both groups the drug was given by 1-hr i.v. infusion for 5 consecutive days. Drug efficacy was evaluated in 72 (group A: 36, group B: 36) of the 83 patients treated, and the safety was evaluated on 81 patients (group A: 41, group B: 40). There were no significant differences in the background characteristics between the two groups. The overall clinical efficacy judged by the Committee for Evaluation of Clinical Efficacy was "excellent" in 14% and "moderate" in 50% of group A, and "excellent" in 17% and "moderate" in 64% of group B, the efficacy being higher for group B than group A, but the difference was not statistically significant. The overall drug efficacy rate for each type of infection excluding group 2, was slightly higher in group B, but this difference was not significant either. The overall clinical efficacy for each site of infection, was higher for group B but the differences were not significant. The overall clinical efficacy as judged by the attending physicians was "excellent" in 17% and "moderate" in 58% of group A, and "excellent" in 25% and "moderate" in 61% of group B. The intergroup difference was thus smaller than that judged by the Committee. The elimination rates against bacteriuria were 58% for both groups A and B, and the decrease rates including "cleared" were 42% against pyuria for both groups A and B. Bacteriological evaluation, showed that there was no significant difference in the eradication rates, between group A (65%) and group B (70%). But the eradication rate for gram-positive bacteria was 40% in group A and 81% in group B, there being a significant difference (P less than 0.05) between them. The evaluation of usefulness gave 44% and 53% "satisfactory" rates, respectively, for groups A and B. The results for the "average score" were also the same in both groups. There were no side effects in any of the 81 patients examined. Abnormal laboratory test values attributed to the drug were seen only in 3 and 2 patients in groups A and B, respectively, there being no difference between the groups.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1984

Effect of antianginal agents on arteriolar diameter in normal and cholesterol-fed rabbits.

The effect of antianginal agents on the cutaneous arteriolar diameter in normal and cholesterol-fed rabbits was investigated. The change in the potency of trapidil to dilate arterioles in cholesterol-fed rabbits was relatively minor when compared with normal rabbits. On the other hand, the potencies of other agents decreased markedly in cholesterol-fed rabbits as compared with normal rabbits. For example, in arterioles of 45-50 micron in diameter, the effective doses of tapidil and dilazep at which the agents dilated the vessel by 20% (ED20) were 1.0 and 0.07 mg/kg i.v., respectively, in normal rabbits, and 2.3 and 2.0 mg/kg i.v., respectively, in cholesterol-fed rabbits. The other agents, such as dipyridamole, diltiazem and nifedipine, virtually did not show any dilating effects on arterioles of cholesterol-fed rabbits at the doses which were effective in normal rabbits. The maximum changes in systemic blood pressure and carotid blood flow induced by the administration of trapidil, dilazep or dipyridamole did not decrease in cholesterol-fed rabbits as compared with normal rabbits. These results suggest that it is more desirable to evaluate the therapeutic potency of antianginal agents in cholesterol-fed rabbits than in normal rabbits, and that the action of antianginal agents on arterioles is not dependent on its action on systemic hemodynamics.

Animals↗
PubMed1984

Dulcerozine-induced duodenal ulcers in rats: a simple, highly-reliable model for evaluating anti-ulcer agents.

Dulcerozine-induced duodenal ulcers in rats were studied in order to establish the optimum conditions for a routine production of ulcers and to elucidate their possible pathogenesis. Single doses of dulcerozine administered either subcutaneously or orally produced a dose-related duodenal ulceration in rats. The ulcerogenic effect of dulcerozine was most potent when given subcutaneously to 24-hr fasted animals at 300 mg/kg. At this dose, deep or perforating ulcers were consistently produced within 18 hr, but mortality due to general toxicity of the agent was excluded at least up to 48 hr. Feeding of animals resulted in a significant reduction in susceptibility to dulcerozine. An antacid and antisecretory agents prevented dulcerozine-induced duodenal ulceration in a dose-dependent manner. Either pylorus ligation or vagotomy completely inhibited duodenal ulceration in response to dulcerozine. In addition, an ulcerogenic dose (300 mg/kg s.c.) of dulcerozine evoked a sustained gastric hypersecretion in pylorus ligated rats. These results suggest that a stimulating action on gastric secretion may be, at least in part, responsible for the ulcerogenic property of dulcerozine. The present study provides a new reliable model for investigations of the pathogenesis and therapy of duodenal ulcer disease.

Animals↗
PubMed1984

[Adenosquamous carcinoma arising in a dermoid cyst (benign cystic teratoma) of the ovary--a case report].

An 89-year-old woman with adenosquamous carcinoma arising in a dermoid cyst (benign cystic teratoma) of the ovary is reported. The malignant change of a dermoid cyst is rare. To our knowledge, this is the first report case of an adenosquamous carcinoma arising in a dermoid cyst of the ovary. Moreover, this case is the oldest patient on record. It is important that dermoid cyst be examined carefully.

Adenocarcinoma↗
PubMed1984

Detection of methamphetamine and amphetamine in a single human hair by gas chromatography/chemical ionization mass spectrometry.

A detailed procedure of an extremely sensitive method for quantitation of methamphetamine and amphetamine in human hair by gas chromatography (GC)/chemical ionization (CI) mass spectrometry (MS) is presented. N-methylbenzylamine was used as an internal standard. The samples, after extraction with an organic solvent, were derivatized with trifluoroacetic anhydride before the GC/MS analysis. Quantitation was made with quasi-molecular ions of the derivatives by selected ion monitoring in the CI mode. The detection limit was about 10 pg in an injected volume. The high sensitivity enabled us to measure both stimulants in a single human hair in actual cases.

Amphetamine↗
PubMed1983

Computer analysis of parentage in relation to maternity and paternity.

General formulas for statistical calculations of parentage by means of blood group analysis are presented in relation to those of maternity and paternity. Based on these formulas, a computer program has been devised to calculate plausibilities, exclusion probabilities, and distributions of log (Y/X) of parentage for any blood groups. The program also gives numerical values of these quantities of maternity and paternity. The values of plausibility and exclusion probability are highest for parentage, and decrease in the order of paternity and maternity. Concerning the distribution of log (Y/X) for true families, a simple relation holds for the ratio of the mean value of log (Y/X) in parentage ap, to that in paternity af, and to that in maternity am as, ap: af: am = 1: 0.6: (0.6)2 This relation holds for all 14 blood groups examined.

Adult↗
PubMed1983

In vivo release of testosterone from vinyl polymer composites prepared by radiation-induced polymerization.

Polymer-testosterone composites with long periods of controlled slow release were made by radiation-induced polymerization in a supercooled state at low temperature using glass-forming monomers. The in vitro release of testosterone from various vinyl polymer composites was found to follow a matrix-controlled process (Q-t1/2). The rate of drug delivery was accelerated with increasing water content of polymers. In experiments in vivo, the composites were implanted subcutaneously in the back of castrated rats during the 30 day test period. The in vivo release rate of testosterone was a little smaller than in vitro. This difference between two releases also increased with the increase of hydrophilicity of polymer. The physiological response in rats was investigated by measuring the weight of ventral prostate and serum testosterone concentration with testosterone-containing composites. The weight of ventral prostate increased linearly with increasing rate of drug release and the serum testosterone concentration could be correlated with the release and with the weight increase of ventral prostate. It was found from microscopic observation that the used polymer carriers had relatively good biocompatibility to cause little foreign body reaction.

Animals↗
PubMed1983

Serum alpha-cysteine proteinase inhibitor levels in pregnancy.

Variation in alpha-cysteine proteinase inhibitor levels in human sera were investigated with special attention to the effect of pregnancy and diseases. The inhibitor level in 111 pregnant women, examined by our previous method, increased as the pregnancy advanced. The correlation coefficient between the level and the duration, r, was 0.578 with the level of significance p less than 0.001. The mean value for 50 pregnant women in the third trimester of gestation was 0.49 +/- 0.04 unit/mL, which was 47% higher than the control value, 0.33 +/- 0.04 unit/mL (p less than 0.001). However, the levels in patients with myoma of uterus, endometritis, cervical cancer, ovarian cyst and ovarian cancer were not significantly different from the control value. From these results, it was concluded that pregnancy enhanced appreciably the alpha-cysteine proteinase inhibitor level in serum.

Adult↗
PubMed1983

Postoperative prognosis as related to blood ketone body ratios in hepatectomized patients.

20 hepatectomized patients, both cirrhotic and noncirrhotic, were studied for the postoperative changes in the arterial blood ketone body ratio and standard liver function tests. It was found that serum enzyme activities, total protein, albumin, total bilirubin, total cholesterol and prothrombin time were less reliable direct indicators of the onset of postoperative hepatic insufficiency than the arterial blood ketone body ratio, which reflects the oxidoreduction state of liver mitochondria. The hepatectomized patients were classified into three groups according to the postoperative changes in the blood ketone body ratio. In the 8 patients of group A, the blood ketone body ratio did not decrease to below 0.7. In the 7 patients of group B, the blood ketone body ratio decreased transiently to 0.4-0.7 and then increased to over 0.7. In the 5 patients of group C, the blood ketone body ratio decreased irreversibly to below 0.4. There were few postoperative complications in group A. In group B, while a variety of complications occurred, they were ameliorated concomitantly with the restoration of the blood ketone body ratio. All group C patients died of multiple organ failure. It is proposed that the arterial blood ketone body ratio is a new and practical approach which enables more effective postoperative management by the accurate evaluation of hepatic functional reserve after hepatectomy.

Aged↗
PubMed1983

Potentiation in various agonists-induced contractions of rabbit mesenteric artery by sulfhydryl reagents.

The role of sulfhydryl and disulfide groups as determinants of rabbit mesenteric arterial responses to various contractile agonists were determined. The addition of 1 X 10(-3) M or of 1 X 10(-2) M 2-mercaptoethanol (2-MEt), a sulfhydryl reagent, produced a leftward displacement (potentiation) of the concentration-response curves of mesenteric arterial strips for KCl. Dithiothreitol (DTT), a reagent that reduces disulfide bonds to sulfhydryl groups, also potentiated the contractile response to KCl in this strip. In mesenteric arterial strips treated with 14 mM KCl after exposure to Ca2+-free Krebs' bicarbonate solutions containing 0.1 mM EGTA, the addition of CaCl2 in a concentration of 2.5 mM caused a contraction (14 mM KCl-induced Ca2+-contraction). The presence of 2-MEt or DTT expectedly potentiated this 14 mM KCl-induced Ca2+-contraction. Verapamil, a calcium antagonist, inhibited the 14 mM KCl-induced Ca2+-contraction both in the presence and the absence of these sulfhydryl reagents. 2-MEt also potentiated the contractile responses of mesenteric arterial strips to histamine, norepinephrine, angiotensin II and prostaglandin F2 alpha suggesting that the potentiation by the sulfhydryl reagent is a nonspecific effect. This sulfhydryl reagent potentiated the each agonist-induced Ca2+-contraction. It is concluded that reduction of a disulfide bridge to a sulfhydryl group at Ca2+-channels increases transmembrane influx of Ca2+ in strips of rabbit mesenteric artery and the increased Ca2+ influx in turn accompanied the contractile responses to various agonists.

Animals↗