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Biomedical subjects

S Kitagawa

Publications and source records attributed to S Kitagawa.

At least 325 records · Page 18Linked to original sources
PubMed1983

Effect of local anaesthetics on human natural killer cell activity.

We explored the effects of local anaesthetics, which are proposed to affect the plasma membrane, on human natural killer (NK) cells. Human NK cell activity was inhibited by lidocaine and procaine in a dose-dependent manner. Procaine inhibited not only NK cytolysis but also the binding of NK cells to target cells when NK cells were pre-incubated with procaine, whereas procaine inhibited NK cytolysis without interfering with the binding when it was added after the binding was completed. These findings suggest that local anaesthetics may inhibit not only the recognition process but also the post-recognition process of human NK cells.

Adult↗
PubMed1982

Effect of microtubule-disrupting agents on superoxide production in human polymorphonuclear leukocytes.

We explored the effects of compounds known or proposed to affect microtubule functions on superoxide (O2-) production in human polymorphonuclear leukocytes stimulated by N-formyl-methionyl-phenylalanine (f-Met-Phe), calcium ionophore A23187 and phorbol myristate acetate. F-Met-Phe-induced O2- production was markedly potentiated not only by microtubule-disrupting agents, including colchicine, vincristine, vinblastine, nocodazole, podophyllotoxin and griseofulvin, but also deuterium oxide (2H2O), which is proposed to stabilize microtubules, and not affected by lumicolchicine. Ionophore A23187-induced O2- production was not influenced by colchicine, and markedly enhanced by 2H2O, whereas phorbol myristate acetate-induced O2- production was not influenced by colchicine, and slightly inhibited by 2H2O. 2H2O did not counteract the effects of colchicine and vice versa. Dibutyryl cyclic AMP and prostaglandin E1 inhibited O2- production stimulated by f-Met-Phe and ionophore A23187, whereas phorbol myristate acetate-induced O2- production was strongly resistant to the inhibitory effect of these agents. The enhancing effect of colchicine and 2H2O on f-Met-Phe-induced O2- production was abolished by dibutyryl cyclic AMP. Colchicine promoted concanavalin A cap formation, and 2H2O produced concanavalin A patch formation, whereas dibutyryl cyclic AMP did not affect the distribution of concanavalin A receptors. In addition, 2H2O and dibutyryl cyclic AMP did not interfere with the colchicine-induced concanavalin A cap formation. These findings suggest that f-Met-Phe, ionophore A23187 and phorbol myristate acetate may activate the oxidative metabolism of human polymorphonuclear leukocytes through different mechanisms, and that microtubule-disrupting agents, 2H2O and cyclic AMP agonists may affect the different steps of the activating system of NAD(P)H oxidase.

Alprostadil↗
PubMed1982

Uptake of hexavalent chromium by bovine erythrocytes and its interaction with cytoplasmic components; the role of glutathione.

Hexavalent chromium (Cr(VI)) anion gradually penetrated into bovine erythrocytes and bound with cytoplasmic components. Its penetration was strongly inhibited by the NH2-reactive agent, 4-acetamido-4'-isothiocyano-stilbene-2,2'-disulfonic acid (SITS) and the SH-reactive agent, N-ethylmaleimide (NEM). Gel filtration showed that the intracellular component that bound to chromium was hemoglobin. The binding affinity of Cr(VI) to hemoglobin in the absence of glutathione in vitro was found to be much less than in intact erythrocytes. However, in the presence of glutathione, the binding affinity of Cr(VI) to hemoglobin became much higher. This indicates that reduction of hemoglobin or Cr(VI) by glutathione is involved in the binding. Cr(VI) interacted only weakly with the membrane and did not cause hemolysis of bovine erythrocytes, unlike heavy metals such as Hg2+.

4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfo↗
PubMed1982

Transport of benzenesulfonic acid derivatives through the rat erythrocyte membrane.

Transport of benzenesulfonic acid derivatives through the rat erythrocyte membrane was studied. The transport properties, such as pH-dependence and effects of reagents reacting with amino-groups, were similar to those to anions like Cl- through the human erythrocyte membrane. The rate of transport of anions through rat erythrocyte membranes is higher than through those of other mammals, such as guinea pig and bovine erythrocyte membranes. This relatively high rate of transport makes the rat erythrocyte membrane suitable for use in comparative studies on the transport of slowly penetrating substances, such as organic anions. The transport velocities of benezenesulfonic acid derivatives were compared with their physico-chemical properties. It was shown that the hydrophobicity has no effect on the transport, but the electronic property has a significant effect: the transport rate is mainly dependent on the e- donor capacities. This feature is the inverse to the well-known inhibitory effect of these derivatives on other anion transport: the inhibition is mainly dependent on the e- acceptor capacities. It is suggested that the transport is regulated by the binding capacity of anions to the transport site.

Animals↗
PubMed1982

Clinical appraisal of his bundle electrocardiogram taken under cardiotomy in congenital heart disease.

The specialized conduction system in the heart was electrophysiologically delineated under cardiotomy in 74 patients with congenital heart disease primarily to determine the topographic relationship of the conduction system to intracardiac structures. Histological study was also done to evaluate the electrophysiological data. Differences were found between the ordinary ventricular septal defect (VSD), inlet-type perimembranous defect, and the ordinary tetralogy of Fallot (TOF), outlet-type perimembranous defect. A superficial run of the His bundle along the lower rim summit of defect was often demonstrated electrophysiologically in large VSD of types II or III, whereas the bundle took marked leftward course in TOF. The right bundle branch (RBB) ran beneath or slightly posterior to the Lancisi equivalent structure (LES) in VSD, while it ran under or slightly anterior to LES in TOF. This papillary muscle could be a rough landmark of the RBB. The course of the RBB in TOF, however, had to be histologically confirmed, since its deep location made electrophysiological delineation difficult. All the sites with a high deflection were the areas where the conduction system was histologically demonstrated beneath the endocardium.

Adolescent↗
PubMed1982

Is the oxygen atom of carbon monoxide coordinated to the copper of hemocyanin?

The carbon monoxide binding site of hemocyanins was studied by comparing the isotope shift of the CO-stretching frequencies in CO-hemocyanins with that of carbon monoxide diethylenetriaminecopper(I)tetraphenylboron in which the carbon atom of CO is coordinated to the copper. Coordination by the carbon atom of CO-hemocyanin is suggested.

Animals↗
PubMed1982

The TM bubble oxygenator: development and clinical application.

A bubble oxygenator (the TM or the OCVC oxygenator) has been produced with development efforts focused particularly on reduction of the nonphysiological characteristics of this type of oxygenator. The structural features of the apparatus are: (1) a reduction to the minimum of adequate priming volume, (2) an oxygen disperser designed to ensure evenly dispersed, uniform-sized bubbles, (3) a volume-control system for the oxygenating chamber (the OCVC system) based on extensive experimental oxygenation studies, and (4) an integrated double microfilter of the gravity-drainage type. Clinical features are: (1) ease of operation in perfusion, (2) reduction in hemolysis and postoperative blood loss, and (3) fewer complications associated with microemboli. Clinical use on over 200 infants and children proved generally very satisfactory. The background of its development is briefly described as are future modification plans.

Cardiac Surgical Procedures↗
PubMed1982

67Ga scanning and upper gastrointestinal series for gastric lymphomas.

67Ga scanning and upper gastrointestinal (UGI) series were performed in 13 patients with gastric lymphomas before any treatment was initiated. Seven of these patients also underwent both examinations after completing chemotherapy and/or radiation therapy. Prior to treatment, all 13 patients had abnormalities on the UGI examination, and 12 of them had abnormalities on the 67Ga scans. In 6 patients, more extensive gastric abnormalities were demonstrated by 67Ga scanning than by UGI examination. Although persistent 67Ga uptake after treatment was indicative of relatively poor therapeutic response, lack of uptake did not always indicate a good response to treatment.

Aged↗