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Biomedical subjects

K Nishiguchi

Publications and source records attributed to K Nishiguchi.

53 records · Page 3Linked to original sources
PubMed1985

Effect of chronic administration of acetaldehyde by inhalation on (Na+ + K+)-activated adenosine triphosphatase activity of rat brain membranes.

The effect of chronic acetaldehyde inhalation on (Na+ + K+)-ATPase (EC 3.6.1.3) activities of subcellular fractions of the rat cerebral cortex was studied. Chronic administration of acetaldehyde by inhalation for 4-21 weeks caused significant increases in the enzyme activities of both the synaptosomal plasma membrane (SPM) fraction and the microsomal (MC) fraction. This indicates the change in neural membrane functions of the brain after acetaldehyde treatment. Mg2+-ATPase activities of both subcellular fractions remained unchanged after acetaldehyde treatment.

Acetaldehyde↗
PubMed1984

Subcellular aldehyde dehydrogenase activity and acetaldehyde oxidation by isolated intact mitochondria of rat brain and liver after acetaldehyde treatment.

The effect of treatment of rats with acetaldehyde on the subcellular NAD+-aldehyde dehydrogenase (EC 1.2.1.3, ALDH) activities and acetaldehyde oxidation by isolated intact mitochondria of the liver and the brain was studied. Inhalation of acetaldehyde caused a significant decrease in the liver mitochondrial low Km-ALDH activity, while brain mitochondrial ALDH activity remained unchanged. Acetaldehyde oxidation by isolated intact liver mitochondria decreased significantly but that by brain mitochondria remained unchanged after acetaldehyde inhalation. These findings raise the possibility that the brain enzyme may be exposed to lower concentration of acetaldehyde than the liver enzyme.

Acetaldehyde↗
PubMed1984

Activity and electrophoretic profiles of brain aldehyde dehydrogenases in mice genetically selected for their ethanol preference.

The activities and electrophoretic profiles of NAD+-aldehyde dehydrogenases (EC 1.2.1.3, ALDHs) in the different brain regions from the mice of inbred C57BL/6J strain (alcohol preferring) and DBA/2 strain (alcohol avoiding) were studied. Kinetic studies on ALDH of the different brain regions revealed the existence of at least two ALDHs in both strains. The ALDH activity in the cerebellum, which was measured spectrophotometrically with 0.1 and 5 mM acetaldehyde as the substrates, was the highest of the three regions and it was about 2-fold higher than that in the cortex in both strains. The ALDH activities of mice of DBA/2 strain were higher than those of mice of C57BL/6J strain in all the regions. Only in the cortex the F1 hybrids (intermediate alcohol preferring) between C57BL/6J and DBA/2 strains had intermediate ALDH activity between their parental strains. Electrophoretic analysis of cortex ALDH revealed that strain differences were observed in the isozyme pattern between pH 7.2 and 7.8 with either acetaldehyde or propionaldehyde as substrate. These findings suggest that the ALDH activity in the cerebral cortex could be related to alcohol preference.

Alcohol Drinking↗
PubMed1983

Activity and electrophoretic profiles of liver aldehyde dehydrogenases from mice of inbred strains with different alcohol preference.

1. The activity of low Km-aldehyde dehydrogenase (ALDH) in the liver mitochondrial fraction (MT-fraction) from male C57BL/6J strain mice (alcohol preferring) was significantly higher than that from DBA/2 mice (alcohol avoiding). The F1 hybrids (C57BL/6J X DBA/2) did not exhibit the intermediate activity to these two strains. 2. Strain differences in liver mitochondrial ALDH isozymes were observed by isoelectric focusing. C57BL/6J strain had two isozymes at pH 7.1 while DBA/2 had no band at this pH. F1 hybrid mice had similar two bands with lower density to those of C57BL/6J at pH 7.1. There was no difference in zymograms of the soluble fraction between C57BL/6J and DBA/2 strains. 3. The present results suggest that the difference in alcohol preference of mice may depend on some restricted ALDH isozymes with different pl or electric mobility rather than the enzymatic activity in the liver MT-fraction.

Alcohol Drinking↗
PubMed1980

Effects of pargyline and diethyldithiocarbamate in vivo treatment on aldehyde dehydrogenase activities of submitochondrial fractions.

1) Aldehyde dehydrogenase with a Km for acetaldehyde in the micromolar range (referred to as low Km-AldDH) is located in the matrix and that with a Km in the millimolar range (referred to as high Km-AldDH) is located in both the matrix and the outer membrane of mitochondria. 2) Pargyline in vivo treatment (100 mg/kg i.p.) caused a complete inhibition of the low Km-AldDH activity of the matrix fraction but caused only a 10% inhibition of the high Km-AldDH activities of the matrix and the outer membrane fractions. Diethyldithiocarbamate (DDC) treatment (700 mg/kg i.p.) caused less than 80% inhibition of the low Km-AldDH activity of the matrix fraction and caused a 20% inhibition of the high Km-AldDH activity of the matrix fraction. DDC treatment had no effect on the enzyme activity of the outer membrane fraction. The difference in the degree of inhibition of the low Km-AldDH activity of the matrix fraction by pargyline and DDC treatment may cause different blood acetaldehyde levels during ethanol oxidation.

Acetaldehyde↗
PubMed1979

Genetic control of responsiveness of rat liver supernatant aldehyde dehydrogenase to phenobarbital and 3-methylcholanthrene.

The responsiveness of the hepatic supernatant NAD+-dependent aldehyde dehydrogenase with a high Km value (high Km-AldDH) to phenobarbital (PB) and 3-methylcholanthrene (3-MC) treatment was studied in male rats of three strains; Wistar, Long-Evans, and Sprague-Dawley. A remarkable strain difference in the response of the enzyme to PB or 3-MC was observed. In rats of the Wistar strain the enzyme activity remained unchanged ("non-responsive") in all rats after treatment with PB while it increased ("responsive") 5- to 19-fo-d in all rats after treatment with 3-MC. The enzyme activity increased 8- to 20-fold and 2- to 8-fold respectively after treatment with PB and 3-MC in all rats of the Long-Evans strain. In rats of the Sprague-Dawley strain the enzyme activity remained unchanged in half of all the rats treated with PB or 3-MC and increased 2- to 7-fold over the basal level in half of the treated rats. The non-responsive rats to PB were all responsive to 3-MC treatment while the responsive rats to PB were responsive in 65% and non-responsive in 35% to 3-MC treatment.

Aldehyde Oxidoreductases↗
PubMedDate not supplied

A retrospective pilot study of indocyanine green enhanced diode laser photocoagulation for subfoveal choroidal neovascularization associated with age-related macular degeneration.

PURPOSE: The effectiveness and limitations of indocyanine green (ICG) enhanced diode laser photocoagulation in treating subfoveal choroidal neovascularization (CNV) associated with age-related macular degeneration (AMD) were investigated retrospectively. METHODS: Thirty-eight eyes of 37 patients with subfoveal CNV received ICG enhanced diode laser (wavelength, 805 nm) photocoagulation in our preliminary series. Nineteen eyes had classic CNV and the others had occult CNV, which was well-delineated on ICG angiography. The rate of anatomical success and functional outcomes were investigated. Factors prognostic of a final visual acuity of 0.1 or better were analyzed. The follow-up period ranged from 6 to 51 months (mean +/- SD = 26.5 +/- 14.4 months). RESULTS: Occlusion of CNV was achieved in 35 of 38 eyes (92%), and 7 eyes (18%) showed recurrence, which was occluded by retreatment in all but 1 eye. Ten eyes (26.3%) showed improvement of visual acuity; 16 (42.1%) showed no change; and in 12 eyes (31.6%) visual acuity deteriorated. Factors prognostic of a final visual acuity of 0.1 or better were good preoperative visual acuity (Mann-Whitney U-test, P =.0028), and a relatively short distance between the edge of laser burns and the center of the foveal avascular zone (unpaired t-test, P =.0285). CONCLUSION: Indocyanine green enhanced photocoagulation achieved a higher anatomical success rate but functional outcomes equal to those with argon or krypton laser photocoagulation. A controlled prospective study is necessary to prove the efficacy of this treatment.

Aged↗
PubMedDate not supplied

Serum human hepatocyte growth factor (hHGF) is elevated in patients with metastatic gastric carcinoma.

BACKGROUND/AIMS: Hepatocyte growth factor (HGF) is a stromally derived protein growth factor that modulates epithelial cell proliferation and motility. HGF may therefore be involved in tumor progression. METHODOLOGY: We measured the immunoreactive (ir)-HGF concentration in the sera of 56 patients with human gastric carcinoma, using an enzyme-linked immunosorbent assay and evaluated its association with clinical and histopathologic factors. Clinical stages were classified in accordance with The General Rules for TNM Classification (International Union Against Cancer). RESULTS: The serum hHGF concentrations from patients with gastric carcinoma significantly increased with increasing pathologic tumor grades. Also, there were significantly higher concentrations in patients with nodal metastasis compared to patients without metastasis. The serum hHGF concentrations in patients with liver metastasis were significantly higher than in patients without liver metastasis. CONCLUSIONS: These data show that the serum hHGF concentration is elevated in gastric carcinoma patients with liver and nodal metastasis. In multivariate analysis, the serum hHGF concentration was found to be the most important independent factor in predicting overall survival. Thus, the current results suggest that HGF may be important in the progression and metastasis of gastric carcinoma.

Aged↗
PubMedDate not supplied

Prognostic factors of advanced gastric carcinoma without serosal invasion (pT2 gastric carcinoma).

BACKGROUND/AIMS: The purpose of this study was to investigate the prognostic factors of advanced gastric carcinoma without serosal invasion (pT2 gastric carcinoma), for the planning of therapeutic strategy. METHODOLOGY: Prognostic factors were evaluated by univariate and multivariate analysis in a total of 304 curatively resected pT2 gastric carcinoma patients in whom the tumor invaded the muscularis propria or the subserosa. RESULTS: Macroscopic type, depth of invasion, lymph node metastasis and venous invasion were significantly related to outcome, using univariate analysis. Lesions resembling early gastric carcinoma had better prognosis than lesions belonging to one of the Borrmann types. Multivariate analysis (Cox's proportional hazards model) demonstrated that macroscopic type, lymph node metastasis and venous invasion, but not depth of invasion, were significant prognostic factors. CONCLUSIONS: Macroscopic appearance, lymph node metastasis and venous invasion were the important prognostic factors of pT2 gastric carcinoma. Extensive lymph node dissection and aggressive post-operative chemotherapy should be performed, especially in Borrmann type lesions with lymph node metastasis.

Female↗
PubMedDate not supplied

Serum human hepatocyte growth factor (hHGF) is elevated in patients with metastatic gastric carcinoma.

BACKGROUND/AIMS: Hepatocyte growth factor (HGF) is a stromally derived protein growth factor that modulates epithelial cell proliferation and motility. HGF may therefore be involved in tumor progression. METHODOLOGY: We measured the immunoreactive (ir)-HGF concentration in the sera of 56 patients with human gastric carcinoma, using an enzyme-linked immunosorbent assay and evaluated its association with clinical and histopathologic factors. Clinical stages were classified in accordance with The General Rules for TNM Classification (International Union Against Cancer). RESULTS: The serum hHGF concentrations from patients with gastric carcinoma significantly increased with increasing pathologic tumor grades. Also, there were significantly higher concentrations in patients with nodal metastasis compared to patients without metastasis. The serum hHGF concentrations in patients with liver metastasis were significantly higher than in patients without liver metastasis. CONCLUSIONS: These data show that the serum hHGF concentration is elevated in gastric carcinoma patients with liver and nodal metastasis. In multivariate analysis, the serum hHGF concentration was found to be the most important independent factor in predicting overall survival. Thus, the current results suggest that HGF may be important in the progression and metastasis of gastric carcinoma.

Carcinoma↗