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Biomedical subjects

K Seki

Publications and source records attributed to K Seki.

At least 433 records · Page 24Linked to original sources

Tumoricidal adsorption of Staphylococcus aureus organisms on Ehrlich ascites tumor cells sensitized with rabbit antibody.

A tumoricidal effect was observed when protein A-bearing Staphylococcus aureus organisms were adsorbed on Ehrlich ascites tumor cells previously sensitized with antiserum from a rabbit immunized with Ehrlich ascites tumor cells. Electron micrographs showed that staphylococci were firmly attached to the tumor cells, which might explain how effectively the attached cocci killed the tumor cells. The tumoricidal effect was confirmed not only by an in vitro experiment but also by an in vivo one. The possible applications of the tumoricidal adsorption as an indicator for staphylococcal virulence or for selective anti-tumor action was discussed.

Adsorption↗

Changes in the concentrations of plasma steroid hormone and plasma 13, 14-dihydro-15-oxo-prostaglandin F2 alpha in late pregnancy rabbits treated with an inhibitor of 3 beta-hydroxysteroid dehydrogenase.

Changes in the concentrations of progesterone, 17 beta-estradiol and 13, 14-dihydro-15-oxo-prostaglandin F2 alpha (PGFM) were evaluated in the peripheral plasma of rabbits during late pregnancy by treating trilostane, an inhibitor of 3 beta-hydroxysteroid dehydrogenase, in an attempt to obtain further insight into the involvement of progesterone and prostaglandin (PG) in the initiation of parturition. The concentrations of progesterone were 18.8 +/- 2.2 ng/ml (mean +/- SE, n = 6) before administration of the inhibitor, significantly (p less than 0.05) fell to 7.6 +/- 1.0 ng/ml (n = 6) at 30 min, and remained low until 10 h after the drug administration. The concentrations of progesterone were still low (5.4 +/- 0.5 ng/ml, n = 6) at 20-24 h after administration of the inhibitor, and were also low (4.9 +/- 2.2 ng/ml, n = 6) at delivery. Premature deliveries occurred at 28.8 +/- 2.0 h after injection of trilostane (on days 29 of gestation). Increased concentrations of PGFM were observed at delivery. However, administration of trilostane induced no discernible changes in the concentration of estradiol. These findings suggest that delivery is induced by progesterone withdrawal and that synthesis prostaglandin F2 alpha is remarkably increased at delivery in the rabbit.

3-Hydroxysteroid Dehydrogenases↗

Functional evaluation of the adenohypophysis with metoclopramide in hyperprolactinemic-amenorrheic women in relation to radiological findings on the sella turcica.

The responses of the adenohypophyseal hormones to metoclopramide (MCP) were evaluated in hyperprolactinemic women with various radiological findings on the sella turcica. Serum PRL concentrations significantly increased after MCP administration in normal women, hyperprolactinemic patients with normal sella and patients with microadenoma, but not in macroadenoma patients with and without suprasellar expansion (SSE). The PRL response to MCP administration was significantly lower in hyperprolactinemic patients than in normal women. Serum TSH concentrations significantly increased after MCP administration in each group of subjects. The TSH response to MCP was significantly higher in patients with normal sella and patients with microadenoma than in normal women. However, the responses of PRL and TSH to MCP were not significantly different between patients with normal sella and patients with microadenoma. Therefore, they were not considered useful in distinguishing tumorous from nontumorous hyperprolactinemia. Serum LH concentrations significantly increased after MCP administration in patients with normal sella, patients with microadenoma and macroadenoma patients without SSE, but not in normal women or macroadenoma patients with SSE. The LH response to MCP was significantly higher in patients with microadenoma than in patients with normal sella. Serum FSH concentrations significantly increased after MCP administration only in patients with microadenoma. The different responses of the adenohypophyseal hormones to MCP in hyperprolactinemic women with various radiological findings on the sella turcica may be explained by the difference in the hypothalamic dopamine activity and in the impairment of the hypothalamic-pituitary system due to pituitary tumor.

Adenoma↗

Twenty-four hour secretory pattern of prolactin in hyperprolactinaemic patients with pituitary micro- and macroadenomas.

No nocturnal increase of prolactin (Prl) secretion during sleep has reportedly been discernible in most cases of hyperprolactinaemic patients with pituitary tumour. However, subjects previously evaluated, were in the majority, patients with large pituitary tumour. In the present study, 24 h secretory pattern of Prl was evaluated in 4 hyperprolactinaemic women with pituitary microadenoma and in 4 hyperprolactinaemic women with pituitary macroadenoma. Nocturnal increase of Prl secretion was observed in patients with microadenoma, but not in patients with macroadenoma. The nocturnal increase of Prl secretion in patients with microadenoma may reflect the function of the adenoma cells, and may suggest that the basic central nervous system programme governing Prl secretion in normals is qualitatively preserved in these patients. Alternatively, the nocturnal increase of Prl secretion may reflect the function of the normal lactotrophs remaining in these patients.

Adenoma↗

Characterization of an established cell line from human immature teratoma of the ovary and effects of retinoic acid on cell proliferation.

A human immature teratoma cell line was established from tumor tissue of the ovary. The cell line, designated YK , synthesized and secreted alpha-fetoprotein, but there was a gradual decrease in the synthesis of this protein during serial passage. The doubling time at passage 43 was about 20.3 hr, and the plating efficiency was 30 to 40%. Tumorigenicity of the cell line in athymic nude mice was 100% even when 10(4) cells were inoculated s.c. When the cell line was cultivated for 5 days in the presence of 80 microM retinoic acid, proliferation was completely inhibited, while alpha-fetoprotein secretion into the medium was increased. Specific lactate dehydrogenase activity in the tumor grown in nude mice as well as in the cultured cells was 8 times higher than that in the original tumor. The activity of alpha-hydroxybutyrate dehydrogenase in the original tumor was similar to that in the tumor grown in nude mice, while the activity in the cultured cells was about 2.5 times higher than those in both original tumor and the tumor grown in nude mice. The original tumor had all five ordinary bands of lactate dehydrogenase isoenzymes. In contrast, both the cultured cells and the tumor grown in nude mice had a characteristic band which was considered to have similar electrophoretic mobility as testicular lactate dehydrogenase X isoenzyme in humans.

Animals↗

Concentrations of non-glucose polyols in serum and cerebrospinal fluid from apparently healthy adults and children.

Six non-glucose polyols--mannose, fructose, 1-deoxyglucose, mannitol, glucitol, and inositol--were identified and evaluated in human serum and cerebrospinal fluid by gas-liquid chromatography and by gas-liquid chromatography/mass spectrometry. Concentrations of fructose, mannose, and inositol in the serum of healthy persons or children without metabolic diseases varied with age, as already reported for 1-deoxyglucose. Fructose, inositol, and glucitol concentrations in cerebrospinal fluid significantly exceeded those in serum. The method described here for determining polyols and for evaluating polyol patterns in serum, as well as the resulting data on children and healthy subjects, should be useful in investigations of the clinical and physiological significance of polyols.

Adolescent↗

Systolic time intervals and impedance cardiogram in pregnant and toxemic women.

STI measurements and impedance cardiography were carried out during gestation and post partum in 231 cases. In normal pregnant women, prolongation of the Q-I interval, isometric contraction time (ICT), preejection period (PEP) and shortening both of the Q-II interval and ejection time (ET) were all marked in late stages of pregnancy. Mean values for stroke volume (SV), cardiac output (CO) and cardiac index (CI) were at the maximum at 16-23 weeks of pregnancy, and then fell in the antepartum period. The total peripheral resistance (TPR) at 16-23 weeks of pregnancy was lower than in other periods. In the postpartum period, the heart rate was lowered, and the Q-II interval and ICT were prolonged. In toxemic pregnancy, SV, CO and CI were lower than those of the normal group and various changes in STI were more apparent than those of non-toxemic pregnants in the supine position. By the postural change from supine to left lateral in toxemia, the improvement in STI was not as good as in the normal pregnant group and, moreover, SV and CO were decreased and TPR was increased. These results suggest that in toxemic pregnancy the left ventricle might be less complaint and less sensitive to the increase in venous return.

Adult↗