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Biomedical subjects

H Oda

Publications and source records attributed to H Oda.

At least 433 records · Page 24Linked to original sources

Capacitation-related changes in antigen distribution on mouse sperm heads and its relation to fertilization rate in vitro.

The anti-mouse sperm monoclonal antibody OBF13 did not react with fresh epididymal sperm. However, when sperm were incubated in a culture medium capable of inducing capacitation, the entire head of the sperm began to react with this antibody. This change of reactivity was not observed when sperm were incubated in a Ca2+-free medium. The change of the reactivity to the antibody was studied in relation to the fertilizing ability of sperm as measured in an in vitro fertilization system; a significant correlation was observed between the appearance of head-stained sperm and fertilization rate.

Acrosome↗

Characterization of a kidney antigen defined by a mouse monoclonal antibody K2.7.

Analysis by indirect immunoperoxidase staining of tissues demonstrated that monoclonal antibody (mAb) K2.7 derived from a mouse immunized with a renal cancer cell line OS-RC-2 was reactive with the tissues of all 36 normal kidneys examined, including two fetal kidneys, 22 of 25 renal cell carcinomas (RCCs) and one of 15 gastric cancers, but not with 23 normal tissues from 11 different organs or 41 malignant tissues from 10 different organs. mAb K2.7 was reactive with the kidneys of several animal species. Positive staining was seen on tubular epithelial cells of the kidney. Thus, the antigen recognized by mAb K2.7 appeared to be an interspecies kidney specific antigen. Results obtained by protein A (PA) assays with a cultured cell panel were consistent with those of staining and confirmed the restricted expression of the antigen. Immunochemical analysis revealed that mAb K2.7 reacted with molecules of 63,000, 60,000 and 43,000 daltons.

Animals↗

Effect of dietary ascorbic acid, cholesterol and PCB on cholesterol concentrations in serum and liver in a rat mutant unable to synthesize ascorbic acid.

The effect of ascorbic acid deficiency and excessive ascorbic acid intake on serum and liver levels of cholesterol and lipids was investigated in ODS-od/od (OD) rats fed a normal diet, a cholesterol-containing diet or a polychlorinated biphenyl (PCB)-containing diet. The OD rat is a rat mutant unable to synthesize ascorbic acid. In OD rats, the dietary requirement of ascorbic acid to maintain normal growth and normal levels of cholesterol in serum and liver is about 300 mg of ascorbic acid/kg diet. In control (ODS-+/+) rats that can synthesize ascorbic acid, dietary addition of 0.5% cholesterol and 0.25% cholic acid caused elevation of cholesterol concentrations in serum and liver, elevation of total lipids in liver and reduction of the ratio of high density lipoprotein (HDL) cholesterol to total cholesterol in serum. Dietary addition of PCB (200 mg/kg diet) caused elevation of serum concentration of cholesterol and of the ratio of HDL-cholesterol to total cholesterol in serum. In OD rats fed a normal diet, ascorbic acid deficiency slightly elevated serum concentration of cholesterol, elevated liver concentration of cholesterol and reduced the ratio of HDL-cholesterol to total cholesterol in serum; and ascorbic acid excess did not affect serum and liver concentrations of cholesterol and the ratio of HDL-cholesterol to total cholesterol in serum. In OD rats fed a cholesterol-containing diet, ascorbic acid deficiency elevated serum and liver concentrations of cholesterol, and did not affect the ratio of HDL-cholesterol to total cholesterol in serum; and ascorbic acid excess did not affect serum and liver concentrations of cholesterol and the ratio of HDL-cholesterol to total cholesterol in serum.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Long-term effects of dietary polychlorinated biphenyl and high level of vitamin E on ascorbic acid and lipid metabolism in rats.

Long-term feeding of purified diets containing (per kg diet) 100 mg of polychlorinated biphenyl (PCB) and 1000 mg of vitamin E (RRR-alpha-tocopheryl acetate) to male Wistar rats was carried out. Rats fed a diet containing PCB rapidly became hypercholesterolemic and maintained high cholesterol levels throughout the 240 d of the experiment. Rats fed a high dietary level of vitamin E plus PCB had higher serum cholesterol and lower liver cholesterol than rats fed a lower level of vitamin E plus PCB. In rats fed PCB, urinary excretion of ascorbic acid was higher than in rats not fed PCB. Urinary ascorbic acid was lower in rats fed high levels of vitamin E plus PCB than in those fed the normal levels of vitamin E plus PCB. Rats fed PCB had lower liver vitamin A storage and higher vitamin A in kidney than rats not fed PCB. This implies that a redistribution of vitamin A occurred in rats fed PCB. Histological observations revealed that central halves of the hepatic lobules of rats fed PCB showed distinct changes consisting of hypertrophy of hepatocytes in the perivenous region and accumulation of vacuoles (lipid droplets) in the cells in the remaining affected portion. Administration of a high dose of vitamin E could not ameliorate this lesion while the treatment depressed effectively the lipid peroxidation. This suggests that the lipid peroxidation was not responsible for the hepatic damage induced by PCB.

Animals↗

Purification of a kappa-carrageenase from marine Cytophaga species.

A mixture of extracellular carrageenases was isolated from the cell-free medium of a culture of marine Cytophaga sp. 1k-C783 grown on ZoBell 2216 E broth with 0.1% commercial carrageenan. A single active peak of kappa-carrageenase was separated and purified from the mixture by ammonium sulfate precipitation, ion-exchange chromatography, and Sephadex G-200 gel filtration chromatography. Molecular weight of the purified kappa-carrageenase was estimated as 100,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The purified kappa-carrageenase had pH optimum 7.6 and temperature optimum 25 C.

Bacteria↗

Effects of intranasal administration of atrial natriuretic hormone on spontaneously hypertensive rats.

The effects of the intranasal administration of synthetic alpha-human atrial natriuretic polypeptide (alpha-hANP) were investigated in 14 anesthetized spontaneously hypertensive rats (SHR; Okamoto-Aoki strain). They were given intranasally synthetic alpha-hANP in distilled water at doses of 10 micrograms/kg, 50 micrograms/kg and 100 micrograms/kg. Intranasal application of 200 microliter of distilled water as a control was also performed in 3 anesthetized SHR. Sixteen anesthetized SHR were examined for the effects of intravenous administration of alpha-hANP at doses of 4 micrograms/kg, 10 micrograms/kg, 20 micrograms/kg and 40 micrograms/kg. Urinary volume and the urinary excretion of sodium increased 2- to 3-fold during the 50 minutes following intranasal administration of a single dose of 50 micrograms/kg or 100 micrograms/kg, although neither the urinary volume nor the urinary excretion of sodium increased after intranasal administration of 10 micrograms/kg of alpha-hANP or 200 microliter of distilled water. There were no significant changes in arterial pressure or heart rate after the intranasal administration of synthetic alpha-hANP or distilled water. In contrast, arterial pressure was decreased and urinary volume and urinary excretion of sodium were increased, in a dose dependent manner, within 5 minutes after intravenous bolus-injection of alpha-hANP and returned to their baseline levels within 20 minutes. These results indicate that intranasal administration of synthetic alpha-hANP exerts its diuretic effect without concomitant changes in arterial pressure or heart rate in SHR.

Administration, Intranasal↗

Left ventricular responses to dopamine in dilated cardiomyopathy as assessed by two-dimensional echocardiography and compared with findings of thallium-201 scintigraphy.

The effects of dopamine on the left ventricular regional wall motion were studied in 11 patients with dilated cardiomyopathy by use of two-dimentional echocardiography and compared with the findings on the uptake of thallium-201. There were no significant changes in heart rate after dopamine infusion (6 micrograms/kg/min). However, the administration of dopamine significantly reduced PEP/ET and increased the systolic blood pressure, fractional shortening, ejection fraction and mVcf. The percentage of segments with reduced thallium-uptake area was significantly higher in abnormal wall motion segments than in normal wall segments both before and after dopamine administration. The percentage of segments with reduced thallium-uptake area was significantly higher in abnormal wall motion segments after loading than in normal wall segments before loading or in dopamine responding segments. However, in reduced uptake area, the asynergy of the left ventricle was improved significantly after dopamine administration. These results demonstrated that the abnormality of Tl-uptake was correlated roughly to the asynergy of the left ventricle, but that the state of remaining myocardium was not necessarily evaluated correctly by Tl-uptake. Dopamine loading seemed to be useful for more accurate evaluation of myocardial residual function.

Cardiomyopathy, Dilated↗

Renal haemodynamics and comparative effects of captopril in patients with benign- or malignant-essential hypertension, or with chronic renal failure.

Effects of captopril on arterial pressure (AP) and renal function were investigated in patients with non-malignant "benign" or malignant phase essential hypertension (EH group), or with chronic renal failure (CRF group). After captopril administration, AP and renal vascular resistance (RVR) decreased significantly, and renal blood flow (RBF) and plasma renin activity (PRA) increased in both groups. Glomerular filtration rate (GFR) increased in the EH group, but was unchanged in CRF. Filtration fraction decreased in the malignant hypertension and CRF groups. Significant correlations were found between baseline PRA and baseline RVR, and the captopril-induced decrease in mean AP, decrease in RVR, increase in RBF, and increase in GFR in the EH group, while these associations were not observed in CRF. These results indicate that the high AP, RVR, suppressed RBF and GFR in the EH group were closely related to activity of the renin-angiotensin system, but not so the low RBF and GFR in CRF. Small doses of captopril may improve impaired renal function in EH, and may not cause deterioration in the CRF group.

Captopril↗

Vitamin D3 metabolism in idiopathic osteonecrosis of femoral head.

Eighteen cases of idiopathic osteonecrosis of the femoral head were studied. Serum concentrations of 25(OH)D3, 24, 25(OH)2D3 and 1,25(OH)2D3 were 19.4 +/- 8.7 ng/ml, 1.04 +/- 0.44 ng/ml and 16.7 +/- 7.9 pg/ml (mean +/- SD) respectively. These values were significantly lower than those of control (26.5 +/- 15.5 ng/ml, 1.91 +/- 0.77 ng/ml and 26.9 +/- 13.7 pg/ml, respectively) (p less than 0.01). Abnormal values of serum calcium (Ca) were detected in two cases, inorganic phosphate (iP) in two cases and alkaline phosphatase (Al-Pase) in two others with no other abnormal values in blood biochemistry. Histological findings in nine cases of iliac bone were those of osteomalacia in five cases and those of osteoporosis in four cases. These results suggest the possibility of bone metabolism abnormalities due to abnormal vitamin D3 metabolism as a background of osteonecrosis of the femoral head.

Adult↗