Biomedical subjects

I Yoshitomi

Publications and source records attributed to I Yoshitomi.

5 recordsLinked to original sources

PubMed1994

[Total aortic root replacement exclusively with full-thickness suturing].

This paper describes two cases of total aortic root replacement using a valved conduit with a side branch. The full-thickness suturing technique was exclusively used at all anastomotic sites, and some technical devices are also presented. The conduit and a Hemashield Woven Double Velour graft used to make it were found very beneficial for the operation of this kind, and our procedure will equally provide every surgeon with a good result.

Aged↗

PubMed1993

[A case of double-valve replacement in a patient with idiopathic thrombocytopenic purpura].

The aortic and mitral valve replacements were successfully performed in a case with idiopathic thrombocytopenic purpura. High-dose-gamma-globulin therapy and splenectomy had been tried. Neither of them, however could increase thrombocyte. After administration of Danazol treatment, thrombocytes moderately increased. With no expectation for further increase in thrombocytes, it was decided to carry out the open heart surgery with the aid of transfusion of thrombocyte-rich fresh plasma. Haemostasis after cardiopulmonary bypass required much longer time as 3 hours than in usual cases, but being successfully controlled. It has been reported that the effectiveness rate of the high-dose-gamma-globulin therapy ranges from 80 to 90%. Therefore this strategy will be the first choice in a case with ITP requiring open heart surgery. In the event that the strategies, including splenectomy, failed, other means such as Danazol therapy and transfusion of thrombocyte-rich fresh plasma should be considered.

Aortic Valve↗

PubMed1989

alpha-Fluoromethylhistidine decreases the histamine content of the rat right atrium under the influence of sympathetic activity.

alpha-Fluoromethylhistidine (alpha-FMH; 65 mg/kg, i.p.), a specific inhibitor of histidine decarboxylase, significantly decreased the histamine content of the rat right atrium in a time-dependent manner; the maximal decrease of 22.2% was observed 4 h after injection. However, alpha-FMH had no significant effect on the histamine content of the left atrium or the ventricles. The alpha-FMH-induced decrease in the right atrial histamine content was not observed in rats pretreated with 6-hydroxydopamine (25 mg/kg, i.p.). Two i.p. injections of 10 and 5 mg/kg of propranolol and the cardioselective beta 1-adrenoceptor antagonist metoprolol almost completely inhibited the alpha-FMH-induced histamine decrease. On the other hand, phentolamine (10 mg/kg, i.p.) had no influence on the histamine-decreasing action of alpha-FMH. These results suggest that in the rat right atrium there is a histamine pool where a rapid turnover of histamine is maintained by normal sympathetic activity.

Animals↗

PubMed1986

Involvement of opioid and non-opioid mechanisms in footshock-induced enhancement of brain histamine turnover in mice.

Naloxone (1-10 mg/kg, i.p.) dose-dependently inhibited the footshock-induced elevation in levels of tele-methylhistamine (t-MH), a predominant metabolite of brain histamine (HA), although this compound had no effect on the HA dynamics in the non-shocked control mice. Footshock significantly enhanced the HA depletion induced by alpha-fluoromethylhistidine, a specific inhibitor of histidine decarboxylase. However, in mice treated with naloxone (5 mg/kg, i.p.) footshock did not significantly facilitate the alpha-fluoromethylhistidine-induced HA depletion. In mice which had been rendered morphine-tolerant following an s.c. implantation of a pellet containing 50 mg of morphine base 3 days before, footshock produced no significant elevation of the t-MH level. The treatment with alpha-methyl-p-tyrosine, p-chlorophenylalanine or atropine had no significant influence on the footshock-induced t-MH elevation. The t-MH elevation was the most marked in the midbrain. In the hypothalamus and pons-medulla oblongata, no significant change in the t-MH level was produced by footshock. These results suggest that footshock increases the HAergic activity in the mouse brain partly through activation of opioid-related mechanisms and that alterations in HA dynamics differ with region of the brain.

Animals↗

PubMed1986

Brain histamine turnover enhanced by footshock.

When footshock was given to mice at 15-s intervals for 30-120 min, there was a significant increase in the brain level of tele-methyl-histamine (t-MH), a predominant metabolite of brain histamine (HA). This footshock-induced elevation of the t-MH level also occurred in mice pretreated with pargyline but not in mice pretreated with metoprine. The footshock facilitated the HA depletion induced by a-fluoromethylhistidine. These results suggest that footshock increases the brain HA turnover.

Animals↗