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Biomedical subjects

K Goto

Publications and source records attributed to K Goto.

At least 937 records · Page 52Linked to original sources
PubMed1982

Follicular reconstruction and hormone production by human adenomatous goiter cells in culture.

Morphological and functional properties of dispersed cells of human adenomatous goiter and those of the thyroid tissue adjacent to and distant from the nodular lesion (normal control) were investigated. In the presence of TSH, reconstructive arrangement of adenomatous goiter cells into a three-dimensional follicular structure occurred in a similar manner to that of normal controls. An addition of thyrotropin (TSH) to culture resulted in the secretion of thyroid hormones in control cells, but adenomatous goiter cells showed no response to TSH. It was found that the ratio of rT3, T3, the ratio of an inactive to an active form, was about three times higher in adenomatous goiter than in normal control. These findings suggested that conversion from T4 to rT3 is increased in adenomatous goiter.

Adenoma↗
PubMed1982

Effects of Rb and Cs on the electrogenic Na-pump in rabbit sinoatrial node cells.

The effects of Rb and Cs on the electrogenic Na-pump of the rabbit sinoatrial node cell were studied, using conventional microelectrode techniques. Hyperpolarizations induced by K or its substitutes were recorded from the preparations which were perfused previously with an extracellular K-free solution. The K-induced hyperpolarizations after K-depletion depended linearly on K-concentration in the range of 1.35 to 10.8 mM. When 2 mM Rb was used as an activator, a subthreshold oscillation appeared and the amplitude of the spontaneous action potentials in the Rb solution was larger than with the standard solution. As the concentration of Rb increased, the Rb-activated hyperpolarization increased, but the amplitude of the action potential decreased. In the case of Cs, the induced hyperpolarization was smaller than with K or Rb, and a transient recovery of pacemaker activity and gradual hyperpolarization preceded the true recovery in the standard solution. Since these hyperpolarization effects were not observed after the application of ouabain-containing K-free solution, the hyperpolarizations were considered to be electrogenic. A small hyperpolarization induced by activation of the external site of the Na-pump appears to be necessary for the immediate recovery of automatism from arrest at low resting potentials.

Action Potentials↗
PubMed1982

Eicosapolyenoic acids of serum lipids of Japanese islanders with low incidence of cardiovascular diseases.

Japanese are unique among the peoples of developed countries in having a high intake of eicosapentaenoic acid (C 20:5) from fresh fish and this may in part contribute to their low incidence of cardiovascular diseases. Mass spectroscopic analyses of eicosapolyenoic acids (C20:3, C20:4 and C20:5) were carried out on the serum of aged persons living on Kohama island in Okinawa and known to have the lowest incidence of cardiovascular diseases in Japan. All but 4 of the 77 persons examined (73.94 +/- 7.81 years old) led active fishing-farming lives. The total amount of eicosapolyenoic acids in the serum of persons on Kohama island (46.77 +/- 7.46 mg/100 ml) was higher (p less than 0.001) than that in people on mainland Japan, owing to the higher intake of fresh fish (147.7 g/day). A positive correlation (p less than 0.01) was found between serum C 20:5 concentration (6.82 +/- 2.54 mg/100 ml) and high density lipoprotein concentration (55.38 +/- 13.83 mg/100 ml). In addition, there were positive correlations (p less than 0.01) between serum C 20:3 concentration (6.58 +/- 1.61 mg/100 ml) and total cholesterol (188.60 +/- 32.30 mg/100 ml), and triglyceride and skinfold thickness. The blood pressure level (p less than 0.01), incidence of abnormal ECG (p less than 0.05), and salt intake (6.2-8.3 g/day) estimated from urinalysis, were all lower than the average figures for Japanese of similar ages. No persons examined showed Q-wave on ECG. The percentage of smokers and drinkers were similar for Kohama island and mainland Japan.

Activities of Daily Living↗
PubMed1982

[[Effect of traxanox sodium on type I-IV allergic reactions. Studies on anti-allergic agents VII].

The 48-hour passive cutaneous anaphylaxis (PCA) and passive anaphylactic bronchoconstriction in rats induced by an IgE-like antibody against DNP-Ascaris were inhibited by intravenous treatment with traxanox sodium in a dose dependent manner. In both experiments, traxanox sodium was more potent than disodium cromoglycate (DSCG), especially as an inhibitor of bronchial anaphylaxis. In the PCA test of rats using a double sensitization technique according to the Orr's method, traxanox sodium was demonstrated not to inhibit antigen-antibody combination, but to inhibit the release of chemical mediators at a stage following antigen-antibody combination. Traxanox sodium inhibited the complement dependent immune hemolysis, but not the hypotonic hemolysis in vitro. However it failed to inhibit the Forssman anaphylaxis in the guinea pig in vivo. Traxanox sodium (50-250 mg/kg p.o.) showed an inhibitory effect on the direct passive Arthus reaction (DPAR) of the rats. Furthermore, it delayed the onset of the hyperacute form of experimental allergic encephalomyelitis (EAE) and reduced mortality in the rats. DSCG was less effective on DPAR and EAE. In conclusion, traxanox sodium is considered to have a wider spectrum of anti-allergic activity than DSCG since it has a suppressive effect not only on the type I allergic reaction, but also on the type III and IV allergic reactions.

Anaphylaxis↗
PubMed1982

Glycosaminoglycans of rat colorectal adenocarcinoma.

A transplantable colorectal adenocarcinoma and the normal colonic mucosa derived from rats of ACI/N strain were digested with pronase, and the glycosaminoglycan fractions were obtained by fractionation with cetylpyridinium chloride. The glycosaminoglycan fraction derived from the adenocarcinoma contained substantial amounts of chondroitin sulfate A/C, dermatan sulfate, heparan sulfate, and hyaluronic acid, whereas chondroitin sulfate A/C and dermatan sulfate were undetectable in that derived from the normal colonic mucosa. An increment in the heparan sulfate content was also apparent in the adenocarcinoma, while the level of hyaluronic acid appeared to be unchanged. Analyses of the extract of the tumor tissue with 5mM ethylenediaminetetraacetate (pH 7.0) indicated that heparan sulfate was present largely, if not completely, in the form of proteoglycan.

Adenocarcinoma↗
PubMed1982

[Role of vagus nerves in bronchoconstriction induced by chemical mediators].

The role of the vagal reflex in bronchoconstriction induced by histamine, acetylcholine, serotonin, and PGF2 alpha was investigated in anesthetized dogs using a complete vagal blockade by cooling. We devised a thermode for vagal cooling. The vagal cooling was performed by circulating cold water through the thermode attached to fit snugly around the bilateral cervical vagus nerves. Airway musculature response was measured as a change in ventilation overflow with a modification of the Konzett-Rössler method. Drugs were injected close intraarterially into the right bronchial artery and inhaled into the airway. Afferent impulses of the vagus nerve were abolished by cooling at 0 degree C. When the vagus nerves were cooled to 0 degree C, the ventilation overflow decreased. On the other hand, when the nerves were rewarmed, the ventilation overflow increased again. Bronchoconstriction was produced by close intraarterial injection of histamine, acetylcholine, serotonin, or PGF2 alpha at a dosage of 10 microgram each. The bronchoconstrictions produced by these agents were inhibited by vagal cooling. The bronchoconstrictions induced by histamine, acetylcholine, and serotonin were all 0.00125%, and that by PGF 2 alpha was 0.001%. Inhalations for 10 min were also inhibited by vagal cooling. These findings indicate that the thermode devised in this study is useful for vagal cooling and that vagally mediated bronchoconstriction is a relatively major component of bronchoconstriction induced by chemical mediators.

Acetylcholine↗
PubMed1982

[A quantitative analysis of the phrenic nerve activities during the cough reflex].

The phrenic nerve activity is an appropriate indicator for the output of the respiratory center as a whole, although a quantitative analysis of each of the frequency band components that constitute the neural activities during the respiratory reflex has not yet been made by other investigators. In the present study, we have made a quantitative analysis of each of the frequency band components of phrenic nerve activity during the cough reflex in anesthetized dogs. The efferent activities of the phrenic nerve were recorded from the central cut end of the phrenic nerve. Each fraction of phrenic nerve activity was separated into bands spanning a range of 100 Hz each by a variable filter and analyzed using a program for the power spectrum. The cough reflex was induced by mechanical stimulation of the tracheal mucosa. In the power spectrum analysis of each frequency band, increase in the power of each of the frequency band components was observed during the cough reflex. Particularly, the power of the 2 approximately 100 Hz band components increased significant as compared with the other frequency band components. Such as increase in the power of the 2 approximately 100 Hz band components toward the other frequency band components during the cough reflex was not observed after an i.v. administration of DMPP and lobeline, but the power increased extended over every frequency band. These findings suggest that the process for integrating the cough reflex was different from that of the other respiratory reflexes and that the present method is useful for investigating the central mechanisms of the cough reflex.

Action Potentials↗
PubMed1981

Ascorbic acid inhibition of Na,K-adenosine triphosphatase of rat forebrain without peroxidation of membrane lipids.

Using reagents and membrane preparations from which contamination had been carefully removed, we found that ascorbic acid inhibited rat brain Na,K-ATPase without causing lipid peroxidation, unlike the conventional belief; the inhibition was prevented by catecholamines and EGTA. Ascorbic acid radicals, instead of active oxygen, may play a role in the inhibition.

Adenosine Triphosphate↗
PubMed1981

A new human photosensitive subject with a defect in the recovery of DNA synthesis after ultraviolet-light irradiation.

A non-sensitive, 8-yr-old male patient (termed UV81KO) with only acute recurrent sunburns and without any other physical or neuromental retardations was studied. The patient's skin exhibited lowered minimal erythema doses between 280 and 300 nm monochromatic wavelengths without delayed peaking of erythema. UV81KO skin fibroblasts in culture was 5-fold more sensitive to 254 nm UV killing than normal cells, though the response of obligatory heterozygotes was normal. UV81KO cells were also more sensitive to killings by fluorescent sunlamp (295-300 nm UV-B) radiation, 4-nitroquinoline-1-oxide, and N-hydroxy-acetyl aminofluorene, but not by monofunctional decarbamoyl mitomycin C, bifunctional mitomycin C, and alkylating agents (methyl methanesulfonate, ethyl methanesulfonate, N-methyl-N-nitrosourea). Assays for unscheduled DNA synthesis, T4 endonuclease V-susceptible sites (pyrimidine dimers), endogenous excision-break accumulation by arabinofuranosyl cytosine-plus-hydroxyurea, single-strand-break rejoining, and molecular-weight increase of pulse-chased DNA in irradiated cells indicated no apparently detectable defects in nucleotide-excision repair processes and in replicative bypass in UV81KO cells. Despite the repair proficiency as such, UV81KO cells showed the defective recovery of DNA synthesis after 254 nm UV irradiation with 1 and 5 J/m2, at which dose the recovery occurred in normal cells. The base line level of sister-chromatid exchanges (SCEs) was higher in UV81KO cells (10-12 SCEs/cell) than in normal cells (5 SCEs/cell), although the induction rate of SCEs by 254 nm UV in UV81KO cells was the same as in normal cells. Such clinical, cellular and molecular characteristics and comparison to those in the other photodermatoses (xeroderma pigmentosum, Cockayne's syndrome, the 11961 disorder, Bloom's syndrome) can make a clear distinction of UV81KO from the others. Thus, the UV81KO disorder is put forward as a new photodermatosis with a defect in the recovery of post-UV DNA synthesis.

Cell Survival↗