Search PubMed⌕ Search

Biomedical subjects

K Takeda

Publications and source records attributed to K Takeda.

At least 1,387 records · Page 77Linked to original sources
PubMed1978

Stimulation of prolyl hydroxylase activity by bleomycin.

The activity of purified prolyl hydroxylase (proline, 2-oxoglutarate dioxygenase, EC 1. 14. 11. 2) was enhanced 3 approximately 8-fold at a low concentration of ferrous ion (1 X 10(-5 M) by addition of bleomycin, a glycopeptide antibiotic with antineoplastic activity and a side effect of producing pulmonary fibrosis. The maximum stimulation was attained at a concentration of 15 microgram/ml bleomycin (about 1 X 10(-5) M), which was approximately equimolar with the ferrous ion, one of the cofactors of this enzyme. Addition of bleomycin to the assay mixture resulted in a change of the optimal concentration of ferrous ion from 2 X 10(-3) M to 1 X 10(-5) M. Changing the order of addition of ferrous ion, enzyme and bleomycin in assay medium before incubation at 37 degrees C, the stimulatory activity was varied. Blemycin A2Cu++(Cu++-chelated bleomycin), which scarcely complexed with Fe++, had no enhancing effects on the enzymatic activity. We discuss the possible reasons as to why the activity of prolyl hydroxylase was enhanced by addition of bleomycin in the assay mixture.

Animals↗
PubMed1978

Gold salt in the treatment of bronchial asthma--a double-blind study.

The efficacy of gold salt on bronchial asthma was investigated by double-blind design in 79 patients. The rate of improvement was significantly higher in the gold-treated group (20/28) than in the controls (16/36). This was reflected by greater reduction of requirement for symptomatic medications. Only mild side effects were observed in 14 patients out of 38 gold-treated patients.

Asthma↗
PubMed1977

Different responses to some stimulators of prolyl hydroxylase activities in various rat organs.

Prolyl hydroxylase (proline,2-oxoglutarate dioxygenase, EC 1.14.11.2) of soluble fraction (105 000 X g supernatant) of rat granulation tissues was markedly enhanced by addition of nucleoside triphosphates to the assay medium. But the stimulatory activities of nucleoside triphosphates were very different in fractions derived from tissues of rat. In skin, lung or whole fetal tissues other than granuloma, GTP enhanced the enzymatic activity by 3-4 fold. On the other hand, in kidney, liver and spleen tissues it brought about no enhancement. The same results were obtained even if ATP regenerating system was added in the assay medium. The stimulatory effect of nucleoside triphosphates was not seen with the soluble fraction of liver, but it appeared with the enzyme fraction purified by affinity column chromatography. The same phenomenon was observed by addition of bovine serum albumin instead of nucleoside triphosphates as stimulator. We discuss the possible reasons as to why the responses of the enzyme to stimulators were quite different among various tissues.

Adenosine Triphosphate↗
PubMed1977

Tissue fibrinolytic activity of allergic contact dermatitis.

One of our co-workers was sensitized with a 1% DNCB solution in acetone. Biopsies were obtained from skin lesions 1, 2, 4, 8, 12, 24, 30, 36 and 48 hours after a challenge with 0.1% DNCB solution. In the upper dermis, a rapid decrease of tissue fibrinolytic activity was found which disappeared after 30 hours. In the lower dermis, biphasic changes were observed. Tissue fibrinolytic activity increased one hour and 12-36 hours after challenge, whereas at 48 hours, when erythema was most intensive, it decreased in comparison to the normal activity. Erythema and histological changes of the epidermis and the dermis appeared after approximately 12 hours. As for lymphocytes, T-cells were seen at first. Furthermore, B-cells were noted after approximately 30 hours when marked infiltration began to appear.

Biopsy, Needle↗
PubMed1977

[Effects of a new adrenergic beta-blocking agent, Kö 1400 on the canine heart-lung preparation supported by a donor dog and the perfused hindlimb preparation of the dog (author's transl)].

Using the canine heart-lung preparation supported by a donor, effects of a new adrenergic beta-blocking agent, dl-1-(tert. butylamino)-3-[ (2-propinyloxy) phenoxy]-2-propanol hydrochloride (Kö 1400), on cardiac function, myocardial metabolism, and coronary circulation were studied and compared with those of propranolol. Effects of this substance on the peripheral vascular bed were also studied in the perfused hindlimb preparation of the dog. Kö 1400 produced a positive inotropic and chronotropic effect. Mechanical efficiency of the heart improved after Kö 1400, while it lessened after propranolol. A decrease in the coronary flow was observed in association with a slight increase in myocardial O2 consumption, indicating that the substance exerted a direct constrictive effect on the coronary vasculature. As a beta-blocker, Kö 1400 was found to be 2-3 times more effective than propranolol. The uptake of the free fatty acid (FFA) by the heart was increased by Kö 1400 and the myocardial redox potential improved. In the perfused hindlimb preparation, intraarterial injection of Kö 1400 resulted in a transient increase of the femoral blood flow for a decrease in the flow followed by a sustained decrease. With repeated administration a marked tachyphylaxis was observed.

Adrenergic beta-Antagonists↗
PubMed1977

Effects of coronary vasodilators on large and small coronary arteries of dogs.

Using the isolated perfused heart preparation supported by a donor the effects of vasodilators on the large conductance artery were studied and were compared with those on the small resistive artery and arterioles. Nitroglycerin produced a preferential dilation of the large conductance artery, while dipyridamole produced a dilation only of the small resistive artery and arterioles. Among the "calcium antagonistic" vasodilators tested, only diltiazem produced a dilatation of the large conductance artery, verapamil and nifedipine producing a dilatation only of the small resistive artery and arterioles. These findings indicate that the mechanism of contraction of the large conductance artery is different from that of the small resistive artery and arterioles.

Adenosine↗
PubMed1977

Prolonged sarcotubular regenerative response in frog sartorius muscle.

The sarcotubular system of frog sartorius muscle fibers is found to generate a prolonged depolarizing regenerative response under appropriate experimental conditions. It is shown from a point-voltage clamp analysis that the inward current component responsible for the response lasts on depolarization for hundreds of milliseconds, and reverses its sign when an equilibrium potential is exceeded. The sarcotubular response occurs in F-Ringer solution and is enhanced with EDTA. It also occurs in normal or propionate-Ringer solution containing EDTA without great change in the equilibrium potential. The response is inhibited reversibly with picrotoxin. Partial replacement of Na by K in the propionate-Ringer solution reduces the inward current component which suggests that Na may be the responsible ions.

Animals↗