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Biomedical subjects

S Sakamoto

Publications and source records attributed to S Sakamoto.

At least 685 records · Page 38Linked to original sources
PubMed1984

Viability of the human placental villi in organ culture.

The viability of the placental villi in organ culture was investigated both from the morphological and functional points of view. Morphological viability was judged on the appearance of the villi with special emphasis on the trophoblastic cells and the morphological integrity of the placental villi could be maintained for at least 96 h in organ culture. Functional viability was judged by analyses of delta 5-3 beta-hydroxysteroid dehydrogenase; delta 5,4-isomerase (3 beta-HSD) activity with 14C-pregnenolone as the substrate and by the suppressive effect of the cultivated villi on the secretion of plasminogen activator (PA) obtained from mouse peritoneal macrophages stimulated by OK-432. It was found that the 3 beta-HSD activity and suppressive effect on PA secretion could be preserved for at least 120 h in organ culture.

3-Hydroxysteroid Dehydrogenases↗
PubMed1984

Effects of estrogen and prolactin on thymidine kinase isozyme activities in DMBA-induced rat mammary tumor.

Effects of prolactin or estrogen on the activity of the pyrimidine salvage pathway enzyme thymidine kinase (TK) in 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumors were investigated in ovariectomized rats. Prolactin induced by perphenazine administration significantly enhanced the activities of total TK or its isozyme in the tumors. This specific TK isozyme separated by DEAE-cellulose column chromatography was suggested to be involved in DNA synthesis because it was not affected by dCTP. Its Mr was estimated to be approx. 100 000 by high-performance liquid chromatography. In contrast, estrogen alone did not raise the activity of the specific TK isozyme in the tumors.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1984

Increased activity of thymidine kinase isozyme in human colon tumor.

Thymidine kinase (TK), the salvage pathway enzyme, and its isozymes were examined in normal mucosa and carcinoma of the colon in 13 patients. In colon tumor TK activity increased to 328% of activity of normal colon. The colon TK isozymes were separated from the normal mucosa and carcinoma by DEAE-cellulose column chromatography. The TK isozyme eluted from the column by the elution buffer alone without NaCl was markedly higher (12-fold) in activity in carcinoma than in normal mucosa of the colon and is not affected by dCTP. The TK isozyme unaffected by dCTP has also been reported to be clearly involved in DNA synthesis. This isozyme, whose molecular weight is 100 000 by means of high performance liquid chromatography, is thought to be involved in DNA replication. The results indicate the applicability of the molecular correlation concept to carcinogenesis of colon.

Aged↗
PubMed1984

Corneal findings in a foetus with Fabry's disease.

The cornea of a 22-week foetus with Fabry's disease was examined biochemically and histopathologically. The alpha-galactosidase activity in the cornea was very low compared with that of the normal control. Histopathologic examination revealed that intracytoplasmic lamellar bodies surrounded by a single membrane were present in the epithelial cells. The lamellar bodies were thought to result from the abnormal accumulation of ceramide trihexoside. We conclude that ceramide trihexoside already has begun to accumulate progressively in the epithelial cells in the mid-trimester of gestation.

Adult↗
PubMed1984

A case of pseudodiphallia.

A case of diphallia was presented. Roentogenographic and histological examination revealed pseudodiphallia without any other genitourinary anomalies.

Abnormalities, Multiple↗
PubMed1984

Syntheses of 23-deoxy-23-N-ethyl-23-(2-fluoro-, 2,2-difluoro-, and 2,2,2-trifluoroethyl)amino derivatives of mycaminosyl tylonolide and 4'-deoxymycaminosyl tylonolide.

Derivatives of mycaminosyl tylonolide (1) and 4'-deoxymycaminosyl tylonolide (2) containing N-ethyl-2-fluoro-, 2,2-difluoro- and 2,2,2-trifluoroethylamino groups at their C-23 have been prepared by treating 23-deoxy-23-ethylaminomycaminosyl tylonolide diethyl acetal (14) and its 4'-deoxy analog 15 with 2-fluoro-, 2,2-difluoro- and 2,2,2-trifluoroethyl trifluoromethanesulfonates. The relationship between the antibacterial activity and the numbers of the fluorine atoms introduced in the final products is discussed.

Leucomycins↗
PubMed1984

Osteoblast collagenase: collagenase synthesis by clonally derived mouse osteogenic (MC3T3-E1) cells.

Latent collagenase was isolated by heparin-Sepharose affinity chromatography from the culture medium of clonally derived mouse osteogenic (MC3T3-E1) cells. Collagenase synthesis by MC3T3-E1 cells was significantly stimulated by the addition of parathyroid hormone to the serum-containing culture medium. The cellular origin of the isolated collagenase was confirmed by demonstrating the characteristic 3/4 and 1/4 fragments of collagen alpha-chain, as well as inhibition of the enzyme by anti-mouse bone collagenase antibody.

Animals↗
PubMed1984

Comparison of genome structures among three different strains of avian erythroblastosis virus.

The genomic DNAs of two strains of avian erythroblastosis virus (AEV), AEV-R and AEV-H, were molecularly cloned in Escherichia coli using lambda Charon 16A as a vector. Comparison of the restriction maps of the cloned DNAs with that of AEV-ES4 DNA revealed that R strain is identical with ES4 strain, but totally differs from H strain. The erbB gene product of AEV-R and that of AEV-H were shown to be glycoproteins with molecular weights of 68,000 and 72,000, respectively. Nucleotide sequence analysis of the 3' part of the erbB gene showed that the erbB gene in AEV-R is 126 base pairs (bp) shorter than that in AEV-H, which might result in some difference in tumorigenicity between these viruses.

Alpharetrovirus↗
PubMed1984

Effects of leucovorin and methylcobalamin with N2O anesthesia.

Results of the deoxyuridine suppression test, a good marker for defining biochemical megaloblastosis caused by deficiency of folate and vitamin B12, became abnormal (greater than 10%) after 6 hours of administration of nitrous oxide anesthesia. 5-Formyltetrahydrofolate and methylcobalamin administration during nitrous oxide anesthesia have no remarkable effect on the correction of deoxyuridine suppression test values. On the other hand, 5-formyltetrahydrofolate and methylcobalamin administrated at the end of nitrous oxide anesthesia corrected the abnormal deoxyuridine suppression test values nearly to normal range within 1 hour.

Bone Marrow↗
PubMed1984

Interleukin 1 activity in culture supernatant of lipopolysaccharide-stimulated monocytes from patients with chronic liver disease.

We have developed a monocyte function test to determine the Interleukin 1 activity in lipopolysaccharide-stimulated monocyte culture supernatant, with or without the addition of indomethacin, in order to investigate helper and suppressor functions of monocytes in patients with chronic liver disease. Release of Interleukin 1 from monocytes was increased in patients with liver cirrhosis (p less than 0.01). Activity of suppressor monocytes was increased both in patients with chronic active hepatitis (p less than 0.01 and in those with liver cirrhosis (p less than 0.001). Since these disorders in the immunoregulatory function of monocytes were enhanced with advancement of liver dysfunction, we conclude that the liver plays an important role in maintaining normal monocyte function, and that chronic liver disease probably relates to dysfunction of monocytes.

Adult↗
PubMed1984

[Nonimmunologic hydrops fetalis: a review of 30 cases].

Thirty cases of nonimmunologic hydrops fetalis in 14 hospitals were studied. The incidence of nonimmunologic hydrops fetalis was 1 in 4,330 deliveries at all hospitals and 1 in 4,389 deliveries at Tokyo University Hospital. Among these, 13 cases with various kinds of fetal anomalies and 5 cases complicated by twin to twin transfusion syndrome were found. Polyhydramnios (73%), preeclampsia (20%), anemia (34%), and hypoproteinemia (64%) were the commonest prenatal maternal complications, whereas a high incidence of abnormal NST patterns such as loss of variability was found, although urinary E3 levels were within the normal range. High rates of premature labor, Caesarian section and vacuum extraction were found at the deliveries of nonimmunologic hydrops fetalis. Prenatal diagnoses were made in 30% and 85% of the cases before 1977 and between 1978 and 1982, respectively. Ultrasound examination was confirmed to be very useful in detecting the hydropic state in the later period. The perinatal mortality rate from nonimmunologic hydrops fetalis was high (90%); and it was 100% in the cases with anomalies or twin to twin transfusion syndrome. The main cause of neonatal death was respiratory insufficiency due to hypoplasty of the lungs and pleural effusion.

Edema↗