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Biomedical subjects

T Suda

Publications and source records attributed to T Suda.

At least 901 records · Page 50Linked to original sources
PubMed1982

Predominance of macrophage-colony formation in human cord blood.

To clarify understanding of the characteristics of granulopoiesis during early infancy, we investigated the colony-forming unit in culture (CFUC), in cord blood (CB), in peripheral blood (PB), and in bone marrow (BM) of infants. The macrophage-colonies (M-colonies) were always predominant in the study of colony formation by CB and PB cells from infants, regardless of the source of the CSF used. This result contradicts previous reports which concluded that the colonies were mainly granulocytic type. In the colony formation by BM cells from one-month-old infants, the ratio of M-colonies was significantly higher than that of adult BM cells. The CSF produced by CB and PB mononuclear cells (MNC) from infants stimulated neutrophil-colony formation in the adult BM cells.

Bone Marrow Cells↗
PubMed1982

Hemopoietic stem cells in nude mice transplanted with colony-stimulating-factor-producing tumors.

When pieces of a human pulmonary carcinoma which was producing colony-stimulating factor (CSF) were transplanted into nude mice a marked granulocytosis of 10(6)/mm3 was observed in the nude mice 4 weeks after the transplantation. In order to elucidate the control mechanism of hemopoiesis, we studied the kinetics of the hemopoietic stem cells of these mice. The number of GM-CFC, CFUE, Meg-CFC and CFUS in the whole body increased to 6 times, 8 times, 6 times and 36 times as much respectively as those of the control mice. The increase in the number of these progenitors occurred mainly in the spleen. The sera of these mice contained only CSF. The cycling fraction of GM-CFC and CFUS determined by thymidine suicide technique was increased. From these findings, it could be considered that CSF produced in these mice acted directly or indirectly on CFUS inducing their differentiation into committed stem cells.

Animals↗
PubMed1982

Hemopoietic colony-forming cells in Shwachman's syndrome.

Colony-forming capacities were studied in three Japanese children with Shwachman's syndrome (chronic neutropenia and exocrine pancreatic insufficiency). Bone marrow granulocyte-macrophage colony-forming cells assayed in a soft agar culture were markedly reduced in all three cases. The cytochemical examination of granulocyte-macrophage colonies by a new technique revealed that 90% of the colonies by a new technique revealed that 90% of the colonies consisted exclusively of granulocytes. Erythroid colony-forming cells assayed in a plasma clot culture were significantly reduced in two of the three cases. Bone marrow phagocytic cells did not suppress granulopoiesis in contrast to the cases of idiopathic aplastic anemia. Moreover, the patient serum did not inhibit granulopoiesis of normal bone marrow cells. These results have been discussed with the possibility of involving the hemopoietic stem cells and other additional factors.

Agranulocytosis↗
PubMed1981

Local therapy of carcinoma of the uterine cervix: part I.

One-hundred-fifteen patients with cervical cancer were treated by placing bleomycin, carbazilquinone (Carboquone), and 5-fluorouracil suppositories in contact with cancer lesions located in the vaginal portion of the uterus or by inserting them into the cervical canal, twice a week, one to 14 times. The cancer lesions disappeared form 17 to 33 patients with Stage 0 lesions and 9 of 42 with Stage IA lesions. The remaining lesions were principally found in the deep portion of the cervical glands and tended to decrease the more often the suppositories were applied. This led to the presumption that if this local therapy had been carried on longer it would have eradicated even the remaining lesions from the patients with Stage 0 and IA lesions. The optimal per administration dose of bleomycin appeared to be 30 mg. The use of Witepsol (Dynamit Nobel Aktiengesellschaft, F.R.G.) suppository base was accompanied by frequent adverse reactions to it, which hindered the local therapy from being repeated over long periods of time. An equal amount mixture of hydroxypropyl cellulose and carbomer (Carbopol 934) as the suppository base was accompanied by relatively less adverse reactions, which permitted the prolonged local therapy with the suppositories. A trace of bleomycin was also found in the ovaries, but it did not cause microscopically evident histologic changes, nor did it affect the menstrual cycle. If early cancer can be treated completely by local therapy, it will be useful for the younger patient with early cervical cancer.

Adolescent↗
PubMed1981

Ornithine decarboxylase activity in chick duodenum induced by 1 alpha, 25-dihydroxycholecalciferol.

The effect of cholecalciferol and its metabolites on ornithine decarboxylase activity was investigated in the duodenal mucosa of vitamin D-deficient chicks. The duodenal ornithine decarboxylase activity decreased in animals fed a vitamin D-deficient diet and its retarded activity was increased dose-dependently by a single injection of cholecalciferol. Among various metabolites of cholecalciferol tested, 1 alpha, 25-dihydroxycholecalciferol [ 1 alpha, 25 (OH)2D3] was the most potent stimulator. Stimulation of the enzyme activity was detected as early as 2h after intravenous administration of 1 alpha, 25 (OH)2D3 and a maximal value was attained at 6 h. The maximal value was 27 times higher than the control. In addition, treatment with 1 alpha 25 (OH)2D3 affected the duodenal content of polyamines. The content of putrescine increased to a value of three times that of the control 6 h after the hormone administration. The spermidine content did not change appreciably. The enhancement of duodenal ornithine decarboxylase activity by 1 alpha, 25 (OH)2D3 occurred in parallel with the enhancement of calcium absorption, which was first detected 3 h after the hormone administration. The enhancement appeared to be tissue-specific. It was observed in every intestinal segment, but was highest in the duodenum. Enzyme activity in other tissues was not influenced appreciably by 1 alpha, 25 (OH)2D3. These results clearly indicate that the duodenal biosynthesis of polyamines is regulated by 1 alpha, 25 (OH)2D3, suggesting the possibility that duodenal ornithine decarboxylase may be involved in the calcium absorption mechanism.

Animals↗
PubMed1981

Isolation, identification, and biological activity of 25-hydroxy-24-oxovitamin D3: a new metabolite of vitamin D3 generated by in vitro incubations with kidney homogenates.

A metabolite of 25-hydroxyvitamin D3 has been isolated in pure form from incubation mixtures containing kidney homogenates of chicks given large doses of vitamin D3. The isolation involved methanol--chloroform extraction and six steps of column chromatography. The metabolite was identified as 25-hydroxy-24-oxovitamin D3 by means of ultraviolet absorption spectrometry, mass spectrometry, infrared spectrometry, nuclear magnetic resonance spectrometry, and specific chemical reactions. Use of a sensitive in situ technique revealed that 25-hydroxy-24-oxovitamin D3 enhances intestinal calcium transport in rats approximately as effectively as 24,25-dihydroxyvitamin D3 does. In contrast, 25-hydroxy-24-oxovitamin D3 appeared to be less active than 24,25-dihydroxyvitamin D3 in chicks 24 h after intravenous injection.

Animals↗
PubMed1981

Vitamin D metabolism and its possible role in the developing chick embryo.

The relationship between bone formation and vitamin D metabolism was investigated in the developing chick embryo. Fertilized White Leghorn eggs were incubated at 38 degrees C in an incubator for 21 days. The fresh weight and calcium content of embryonic tibiae began to increase at day 12 and attained maximal values at day 19. Bone alkaline phosphatase and citrate decarboxylation activities, both of which represent osteoblastic activity, also began to increase at days 10-12, reached maximal values at day 19 and sharply declined thereafter. Both bone enzyme activities were highly correlated with CA2+-binding activity in the chorioallantoic membrane measured by the Chelex 100 assay. When mesonephric and metanephric homogenates were incubated with 25-hydroxy[3H]cholecalciferol, a marked and concomitant increase occurred in the metanephric 1 alpha- and 24-hydroxylase activity after day 14. The production of 1 alpha, 25-dihydroxycholecalciferol attained a maximal value at day 19 and decreased thereafter, whereas that of 24,25-dihydroxycholecalciferol continued to increase until hatching. The production rate of 1 alpha, 25-dihydroxycholecalciferol by the metanephros coincided with the changes in Ca2+-binding activity in the chorioallantoic membrane and osteoblastic activity. Since both intestinal calcium absorption and bone mineral mobilization do not occur in embryonic life, these results support the idea that 1 alpha, 25-dihydroxycholecalciferol may be involved directly in bone formation or induction of a calcium-binding protein in the chorioallantoic membrane.

Allantois↗