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Biomedical subjects

J Kato

Publications and source records attributed to J Kato.

At least 523 records · Page 29Linked to original sources
PubMed1986

Natriuretic effect of chronically administered alpha-human atrial natriuretic polypeptide in sodium depleted or repleted conscious spontaneously hypertensive rats.

Hypotensive and natriuretic effects of chronically administered alpha-human atrial natriuretic polypeptide (alpha-hANP) were investigated in conscious spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) in both sodium depletion and repletion. Systolic blood pressure was significantly reduced in SHR and WKY in both sodium deplete and replete states. Urinary sodium excretion was significantly increased in SHR and tended to be increased in WKY on sodium repletion, but remained unchanged on sodium depletion. It is suggested that extracellular fluid volume may be an important determinant factor of the natriuretic action of ANP but may not affect the hypotensive effect.

Animals↗
PubMed1986

Inhibition of the binding of R-5020 and rat uterine progesterone receptors by long chain fatty acids.

Long chain fatty acids were known to interfere with the binding between rat uterine estrogen receptors and estradiol. The effect of long chain fatty acids on the binding between rat progesterone receptors and 3H-R5020 was studied. The binding was inhibited by palmitic acid, palmitooleic acid, arachidonic acid and docosahexaenoic acid. Docosahexaenoic acid was the strongest inhibitor and palmitic acid was the weakest inhibitor. The inhibitory effect of palmitic acid and arachidonic acid was dose dependent. In rat uterine cytosols, there existed an arachidonic acid binding factor which was distinct from progesterone receptor. The inhibitory mechanisms of long chain fatty acids was not clear, but the inhibitory effect was stronger if the number of carbon atoms increased with the number of double bonds.

Animals↗
PubMed1986

[Prostaglandin biosynthesis by pregnant myometrium].

In order to study prostanoid biosynthesis, pregnant myometrium was taken from eleven patients undergoing cesarean section. Homogenates of myometrium were incubated with 14C labelled arachidonic acid and biosynthetic products were studied using silicic acid column chromatography, thin layer chromatography and gas-liquid chromatography. There were two metabolites assumed to be 12-hydroxy-5,8,10-heptadecatrienoic acid (HHT) or hydroxy acid. Concerning the prostaglandins, pregnant myometrium produced 6-keto PGF1 alpha, PGF2 alpha and PGE2. But the conversion rates to each prostaglandin has no relation to the gestational week. Moreover, the conversion rate to each prostaglandin was not higher in the samples taken from the patients with pains than that from the patients with no pains. The total conversion rate to prostaglandins also has no relation to the gestational week or pains. However the PGE2/PGF2 alpha (p less than 0.001) and 6-keto PGF1 alpha/PGF2 alpha (p less than 0.05) ratios were significantly higher in the patients with pains.

6-Ketoprostaglandin F1 alpha↗
PubMed1986

[An endogenous growth factor extracted from the human ovary].

A growth factor which stimulates DNA synthesis in resting mouse Balb/c 3T3 cells (3T3 cells) has been extracted from human follicular ovaries and partially purified. The dialyzed cytosol stimulated 3H-DNA synthesis in 3T3 cells dose-relatedly. When the extract was subjected to salting-out procedures with ammonium sulfate, there was found a 60% saturation cut containing growth promoting activity. Ion exchange on a cation exchanger of the active 60% cut produced an active fraction in the 1M NaCl elute. Gel filtration of ovarian cytosol yielded an active fraction that eluted between chymotrypsin (25,000 MW) and cytochrome C (12,400 MW). The data presented here indicate the presence of an endogenous growth factor in human ovary. The factor appears to be a basic protein, heat-labile and soluble in 40% or less ammonium sulfate, with a molecular weight of between 12,400-25,000. With respect to the biochemical characteristics, this growth factor is quite similar to the porcine ovarian growth factor previously reported.

Animals↗
PubMed1986

[Two cases of carcinoid tumor of the stomach and a collective review of the Japanese literature].

We report two cases of carcinoid tumor of the stomach together with a collective review of the Japanese literature. Case 1 was preoperatively diagnosed as carcinoid, and the lesion, measuring 10 X 7 mm, and located in the body of the stomach, had no metastases. Case 2 was preoperatively diagnosed as gastric cancer and was recognized as a submucosal tumor measuring 5.8 X 4.7 cm in the antrum of the stomach. There were metastases to the brain and the skin, and the patient died on the 50th day after the operation. From a collective review of previous cases, it was ascertained that small carcinoid tumors sometimes had metastases. For this reason, we feel gastrectomy should be performed together with local lymph node resection.

Carcinoid Tumor↗
PubMed1986

[Histopathological changes in endometrial cancer treated with tamoxifen].

Eight cases of endometrial adenocarcinoma, including 7 well differentiated cases (stage Ia three, stage Ib three, stage II one) and I poorly differentiated case (stage IVb), were treated with Tamoxifen (20 mg/day) for 7-14 days. The average age of these patients was 59.1 +/- 10.9 years old and they were all postmenopausal for between 6 months and 30 years. The endometrial tissue was biopsied before Tamoxifen administration and half of it was investigated for progestin receptor (PR) and estrogen receptor (ER) while the remainder was used for histopathological examination. After surgical treatment, some tissue fragments of the endometrium were taken for investigation of PR and ER. The effect of Tamoxifen was then studied for the amount of PR, ER and histopathology. The result was that the amount of PR was increased in well differentiated cases whereas it was unchanged in poorly differentiated ones, and the amount of ER was decreased in all cases. Meanwhile, obvious histopathological changes were noted as follows decrease of glandular epithelial stratification, increased secretory activity, increased epithelial cell size with columnar cell type, increase of transparent, vacuolated cytoplasm, increase of nuclear size with variable shape and prominent nucleoli with marginal aggregation of chromatin. However, no stromal change was noted. Furthermore, the greater the increase in the amount of PR, the more conspicuous histopathological change was noted. It was concluded that Tamoxifen could produce both functional (PR, ER) and morphological (histopathology) changes in endometrial cancers.

Adenocarcinoma↗
PubMed1985

Dispensability of either penicillin-binding protein-1a or -1b involved in the essential process for cell elongation in Escherichia coli.

A strain of Escherichia coli lacking the entire ponB gene and a strain lacking the proximal part of the ponA gene were constructed by substitution with a drug resistance gene. These strains lost either penicillin-binding protein(PBP)-1b or -1a totally and their growth was apparently normal at 30 degrees C and 42 degrees C except that growth of the ponB deletion strain was poor on a nutrient agar plate containing no NaCl at 30 degrees C as well as at 42 degrees C. Transductional experiments to introduce the ponB deletion into the ponA deletion strain, and vice versa, showed that the ponA ponB double deletion was lethal unless the deletion was functionally compensated, e.g., by the presence of a plasmid carrying either gene. Thus, either PBP-1b (ponB) or PBP-1a (ponA), but not both, is dispensable for cell viability, at least under ordinary culture conditions. Transductional experiments also suggested that the gamma component of PBP-1b or the PBP-1b lacking the C-terminal portion encoded in the distal region to the SphI site on the ponB was sufficient for supporting growth of the E. coli cell.

Acyltransferases↗
PubMed1985

Correlation of androgen receptors with histological differentiation in human endometrial carcinomas.

Primary endometrial carcinomas from 35 non-treated patients were investigated by measurement of androgen receptors in the tumor cytosols. Receptor analysis was done with a labelled synthetic androgen, methyltrienolone 3H-R1881 and triamcinolone acetonide, and dextran-coated charcoal absorption. The concentrations of androgen receptors in the endometrial carcinomas were, in decreasing order: highly-differentiated tumors, 15.7 +/- 1.8 (fmol/mg protein, mean +/- SE) (number of cases, 21); moderately differentiated tumors, 4.6 +/- 1.6 (n = 7); poorly differentiated tumors, undetectable in 7 out of 8 cases. Highly-differentiated tumors contained a much greater concentration of receptors than the two less differentiated ones. One highly-differentiated endometrial carcinoma with pyometra virtually lacked the receptor. The moderately differentiated endometrial carcinomas contained very low levels of the receptors. The poorly differentiated tumors virtually lacked the receptors. Metastatic lymph nodes from primary endometrial carcinomas with moderate differentiation had a very low receptor level. From these results, it is concluded that human endometrial carcinomas, particularly with histologically high differentiation, contain a considerable amount of androgen receptor and that the receptor concentrations appear to correlate with the histologic grade of tumor differentiation.

Adult↗