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Biomedical subjects

K Goto

Publications and source records attributed to K Goto.

At least 991 records · Page 55Linked to original sources
PubMed1978

Factors involved in differential Giemsa-staining of sister chromatids.

Microspectrophotometric evaluation of differentially stained sister chromatids made it possible to analyse precisely the factors involved in the Giemsa methods. The concentration of Hoechst 33258, pH of the mounting medium temperature during UV-exposure and the quality (wavelength)of UV-light influenced the differential staining. Exposure of blacklight of 10(-5) M Hoechst 33528-stained brdU-labeled chromosome specimens mounted in McIlvaine buffer (pH 8.0) at 50 degrees C reproducibly allowed differential staining of sister chromatids within 15 min. On the other hand, Korenberg-Freedlender's method using no Hoechst 33258 was also UV-light-dependent. Thus, photolysis of BrdU-substituted DNA was considered the basic mechanism of the Giemsa methods where the photosensitive Hoechst 33258 played a role as a sensitizer.

Azure Stains↗
PubMed1978

Sequential changes of regional circulation in cerebral infarction.

Sequential changes of regional cerebral circulation and effects of spontaneous recanalization of occluded artery on cerebral circulation were observed in 50 patients with cerebral infarction. 1) Luxury perfusion was predominantly recognized in the recanalized patients within 16 days after onset. 2) Impairment of vasomotor responses was almost the same in the recanalized patients and the occluded patients. 3) CO2 response tended to recover about 3-4 weeks after onset, but disautoregulation to induced hypertension persisted up to 2 months after onset. Some clinical problems are discussed.

Adult↗
PubMed1978

Removal by bovine serum albumin of fatty acids from membrane vesicles and its effect on proline transport activity in Escherichia coli.

Bovine serum albumin appreciably stimulated the initial rate and the steady-state level of proline uptake in membrane vesicles, while it had no effect on the oxidase activity for ascorbate-phenazine methosulfate, on which the transport activity depends. Bovine serum albumin showed the strongest stimulatory effect on the transport system among the proteins tested. Three other proteins did not show any effect, while beta-lactoglobulin showed a weaker but appreciable effect on the transport activity. The incubation of membrane vesicles with bovine serum albumin resulted in extensive removal of fatty acids, while none of the other membrane components, including proteins and phospholipids, was removed by this treatment. Fatty acids inhibited the proline transport activity, while the inhibited activity was appreciably restored by incubation with the albumin. An experiment with radioactive fatty acids showed that exogenously-added fatty acids bound firmly to the membrane vesicles and were removed by subsequent incubation with the albumin. The incubation of membrane vesicles for several hours resulted in an increase of fatty acids with a concomitant loss of the transport activity. Subsequent incubation with the albumin resulted in the removal of fatty acids and the partial restoration of the transport activity. Based on these results, it is concluded that bovine serum albumin specifically removed fatty acids from membrane vesicles, resulting in activation of the proline transport system.

Biological Transport↗
PubMed1978

[Anti-allergic activity of 7-acetyl-5-oxo-5H-[1] benzopyrano (2,3-b] pyridine (Y-9000) (author's transl)].

The IgE mediated reactions such as 48 hr homologous passive cutaneous anaphylaxis (PCA) and active anaphylactic bronchoconstriction in rats were inhibited in a dose dependent manner by treatment with 7-acetyl-5-oxo-5H-[1]benzopyranol[2,3-b] pyridine (Y-9000) and disodium cromoglycate (DSCG) given intraperitoneally. The inhibitory activity of Y-9000 was to the same extent as that seen with DSCG. The IgE mediated reactions were also inhibited by oral treatment with Y-9000 but not with DSCG. In addition, the treatment with Y-9000 resulted in inhibition of IgG mediated reaction such as anaphylactic asthma in the passively sensitized guinea pigs and 4 hr heterologous PCA in rats. However, DSCG failed to prevent these reactions. Y-9000 also inhibited the active systemic anaphylaxis of the mouse and non-immunological reactions in rats such as histamine release after an intraperitoneal injection of dextran, anaphylactoid reaction and paw edema induced by the dextran, egg white or carrageenin. This agent had a stimulating effect on the adrenals, and showed glucocorticoid like activity, but bronchodilator and antagonistic activities on chemical mediators were nil. These results suggest that the anti-allergic activities of Y-9000 are elicited by inhibiting the release of allergic mediators in a manner similar to DSCG, and are partially mediated by stressor activity.

Anaphylaxis↗
PubMed1978

Effects of 2-(4-(2-imidazo[1,2-a]pyridyl)phenyl) propionic acid (Y-9213) and anti-inflammatory drugs on erythrocytes, polymorphonuclear leukocytes and lysosomes in vitro.

2-(4-(2-Imidazo[1,2-a]pyridyl)phenyl)propionic acid (Y-9213) with analgesic, antipyretic and anti-inflammatory activities significantly inhibited hemolysis of rat erythrocytes. Activity of Y-9213 (100--500 micrometer) on hemolysis was more potent than that of phenylbutazone, and less potent than that of indomethacin. The spontaneous release of enzymes from rat liver lysosomes by incubation alone was significantly inhibited by Y-9213 (1--100 micrometer) to the same degrees as phenylbutazone or tinoridine hydrochloride. Release of enzymes from the lysosomes by addition of phospholipase C (PLC, 0.03 units/ml) was slightly inhibited by Y-9213 (10--100 micrometer) and phenylbutazone (100 micrometer). Dexamethasone, prednisolone, hydrocortisone and tinoridine hydrochloride (1--10 micrometer) inhibited more potently the PLC-induced release than the spontaneous release. Y-9213 (1--100 micrometer) inhibited considerably the release of enzymes from intact lysosomes of rabbit polymorphonuclear (PMN) leukocytes. The release of enzymes from the PMN leukocyte lysosomes preincubated at 37 degrees C for 15 min was strongly inhibited by dexamethasone, prednisolone and hydrocortisone (1--100 micrometer), but not by Y-9213, phenylbutazone and indomethacin (100 micrometer). Y-9213 (0.1--10 micrometer) also inhibited significantly the phagocytic secretion of lysosomal enzymes from PMN leukocytes without affecting phagocytosis of the particles. Activity of this agent was similar to that of phenylbutazone, and less active than that of indomethacin, dexamethasone or prednisolone. Our results suggest that Y-9213 may stabilize membranes of erythrocytes and lysosomes and inhibit phagocytic secretion of lysosomal constitutents from PMN leukocytes.

Animals↗
PubMed1978

Disappearance of the difference between adrenal A and NA cells in the level of radioactivity after 3H-dopa injection in the hypophysectomized mouse.

Radioactivity in adrenal medullary chromaffin cells of the mouse was examined by autoradiographic methods 15 min to 1 hr after an intraperitoneal injection of 3H-dopa. In the normal control mice, the concentration of radioactivity was significantly higher in the A cells than in the NA cells, whereas in the hypophysectomized mice (9 days after operation by the transauricular method) the radioactivity was evenly distributed in the two cell types. It was suggested that both A and NA cells possessed a special trapping and concentrating mechanism for extracellular dopa and/or its metabolites and that the activity of this mechanism was made greater in the A cells than in the NA cells by the pituitary gland.

Adrenal Medulla↗
PubMed1978

Denervation-induced changes in electrophysiologic parameters of the smooth muscle of the guinea-pig and rat was deferens.

In order to further elucidate the mechanisms by which postganglionic denervation causes changes in the dose-response curves obtained in smooth muscle, microelectrodes have been used to investigate cellular changes in the denervated guinea-pig and rat vas deferens. In the guinea-pig vas deferens, chronic denervation produced a partial depolarization (mean change of 8.5 mV) without any change in threshold for the action potential. In the rat vas deferens there was no change in resting potential but the threshold membrane potential because more negative (6.5 mV). Thus, in both species, but apparently by different mechanisms, the resting and threshold membrane potentials are brought closer together by denervation. Such an effect would clearly contribute to the well documented increase in sensitivity to depolarizing agonists which is produced by chronic denervation. In both species, denervation increased the space constant of the smooth muscle, an indication of increased electrical coupling among the cells. This observation is consistent with morphologic evidence of improved coupling induced by denervation and presented previously from this laboratory. The improved coupling appears to be associated with the increased maximum response of the denervated vasa deferentia of both species. These results are discussed in references to known similarities and differences in electrophysiologic characteristics between normal guinea-pig and rat vasa deferentia.

Action Potentials↗
PubMed1978

Binding of dextran sulfate by virus-transformed cells, with reference to altered growth behavior by its treatment.

Binding of 3H-labeled dextran sulfate on transformed and untransformed cells was studied in relation to the altered growth of transformed cells by this treatment. 3T3 and SV3T3 cells, and the isolated cells (SV3T3-R5) insensitive to dextran sulfate treatment were used. The rate of binding of 3H-dextran sulfate on SV3T3 cells was dose-dependent when examined by the liquid scintillation method. It was revealed in autoradiographic analysis that there was no difference in the binding capacity of 3H-dextran sulfate among 3T3, SV3T3, and SV3T3-R5 cells. The rate of binding proceeded linearly during the first 10 hr and then tended to decline. Thin sections (0.3 approximately 0.5 micron) of SV3T3 cells were autoradiographed to examine the site of localization of 3H-dextran sulfate. Depending on the incubation time with the cells, 3H-dextran sulfate was located first on the cell surface and then in the cytoplasm when incubated further. Finally, silver grains were detected even in the nucleus of SV3T3 cells. This process of localization was similar in 3T3 cells. Binding of 3H-dextran sulfate on SV3T3 cells was independent of the presence of calf serum in the medium.

Binding Sites↗
PubMed1978

The effects of ouabain and alterations in potassium concentration on the sensitivity to drugs and the membrane potential of the smooth muscle of the guinea-pig and rat vas deferens.

Previous work has suggested partial depolarization of the smooth muscles cells to be an important factor in the post junctional supersensitivity induced in the guinea-pig vator in the post junctional supersensitivity induced in the guinea-pig vas deferens by chronic denervation or decentralization. The present experiments were undertaken to explore, under acute in vitro conditions, the relationship between membrane potential changes and sensitivity in the vasa deferentia of guinea pigs and rats. The results indicate that sensitivity was altered whenever resting potential was changed by 7 to 10 mV. The results also indicated that considerable electrophysiologic differences exist between the smooth muscles of the guinea-pig and rat vas deferens. Notably, ouabain or lowered external potassium caused a partial depolarization of the guinea-pig, but not the rat, vas deferens. The results, especially when combined with evidence that the rat vas deferens does possess a considerable amount of (Na+-K+)-adenosine triphosphatase, which is ouabain-sensitive, indicates that under the conditions of these experiments the Na pump is electrogenic in the guinea-pig, but not the rat, vas deferens.

Animals↗