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T Enomoto

Publications and source records attributed to T Enomoto.

At least 19 recordsLinked to original sources
PubMed1979

Effect of thymidine on poly(ADP-ribosyl)ation in vivo.

The addition of thymidine as well as nicotinamide to isolated nuclei resulted in a strong inhibition of poly(ADP-ribosyl)ation, whereas that of hydroxyurea and amethopterin has essentially no effect. The nuclei isolated from the cells immediately after release from thymidine synchronization exhibited a significantly increased activity of poly(ADP-ribosyl)ation. Thereafter, the fluctuation pattern of the activity of poly(ADP-ribosyl)ation in isolated nuclei during the cell cycle was essentially the same as in the case of hydroxyurea synchronization. The activity of poly(ADP-ribosyl)ation in isolated nuclei after treatment with thymidine in vivo increased with the treatment time. The time-dependent increase was also evident in the case of nicotinamide treatment. Little increase in the activity was observed in hydroxyurea and amethopterin treatment. When poly(ADP-ribose) polymerase was extracted from the nuclei isolated from the cells which were pretreated with each of the four compounds, there was no significant difference in the amount among these compounds. The reason for the increase in the poly(ADP-ribosyl)ation in vitro by the in vivo treatment with thymidine is discussed.

Cell Nucleus↗
PubMed1979

Lissencephaly (agyria) on computed tomography.

Unusual computed tomographic findings were observed in two infants with similar clinical pictures including delay in developmental milestones, seizures, decerebrated posture, and microcephaly. Computed tomography revealed small brain with widened subarachnoid space, smooth surface of the brain, uniformly enlarged ventricles, wide sylvian cisterns, and lack of insular opercularization. These findings coincide with pathologic features of lissencephaly (agyria), a rare congenital anomaly of the brain due to interruption of neuronal migration.

Brain↗
PubMed1979

Estrogen receptor in the thymus of the castrated mice.

Sucrose density gradient ultracentrifugation and dextran-coated charcoal adsorption permitted us to characterize the estrogen-binding proteins in cytosols obtained from the thymus, spleen and mesenteric lymph node of the castrated male and female mice of C57BL strain. The thymic cytosol from both sexes incubated with 3H-estradiol-17 beta in the presence of excess unlabeled steroids showed a specific estrogenbinding 4 S protein with its binding capacity of 10(-14) moles/mg protein for males and 4 x 10(-15) moles/mg protein for females, respectively. The dissociation constant was of 4 x 10(-10) M for males and 3 x 10(-10) M for females, respectively. No specific binding was, however, found in the cytosols of the spleen and mesenteric lymph node. Steroid analysis by thin-layer chromatography of the thymic cytosols after incubation of them with 3H-estradiol-17 beta showed that a fair amount (around 60%) of radioactivity was from the undegradated radioactive steroid still bound to 4 S binder in both sexes. Enzyme study and heat experiment revealed that the estrogen specific 4 S binding component in the thymic cytosols bears at least protein in nature and is of heat-labile nature. These results strongly suggest that the thymus of the castrated mice contain a specific estrogen receptor, the nature of which is in part protein and heat-labile.

Animals↗
PubMed1979

Progestin binding in vitro by the brain cell nuclei of ovariectomized oestrogen-primed rats.

The uptake and binding of 17 alpha, 21-dimethyl-19-nor-4,9-pregnadiene-3,20-dione, a synthetic progestin, by the hypothalamus and cerebral cortex of ovariectomized oestrogen-primed rats was examined in vitro. Uptake of this steroid by the medial basal hypothalamus was higher than that by the remaining hypothalamus and cerebral cortex. The component in the cytosol from whole hypothalami which bound the radioactive progestin sedimented in the 7S region when centrifuged in a sucrose density gradient. The tritiated progestin was displaced by incubation with non-radioactive progestin or progesterone but not by oestradiol-17 beta, corticosterone or 5 alpha-dihydrotestosterone (1 mumol/l). No 7S binding component was detected in a similar preparation from the cerebral cortex. The nuclear fraction from whole hypothalami extracted by KCl (0.4 mol/l) contained a progestin-binding complex which sedimented at 9S and which was heat-labile and protein in nature. It was concluded that the hypothalamus of ovariectomized oestrogen-primed rats contains progestin-binding material in the cytoplasm and progestin, bound to such material, is transported from the cytoplasm to the nucleus.

Animals↗
PubMed1979

Computed tomography in tuberous sclerosis--with special reference to relation between clinical manifestations and CT findings.

Concerning the clinical signs and symptoms, we noticed skin white macula in 87%, adenoma sebaceum in 53%, mental retardation in 75%, retinal phacoma in 54% and seizure in 92%. Numbers of nodules ranged from zero to 11, and showed no correlation with aging. Half of the cases showed slight ventricular dilatation, one quarter showed moderate dilatation and the remainder were normal. There was no definite correspondence between size of the ventricle and number of nodules. There were relatively many cases with normal mental state in the group with normal ventricles. In adult cases a large ventricle does not always mean poor prognosis in mental state. Almost all of the cases with cortical atrophy had mental retardation. In the group with moderate dilatation infantile spasms were the most frequent type of seizure. On the contrary, grand mal was most frequent in the normal group. As for the position of nodules there was no difference between the normal and dilated groups. Nodules were predominantly seen in the lateral aspect of the body, trigone of the lateral ventricle and adjacent to the foramen of Monro. Asymmetrical lateral ventricles were noticed in 18%. Incidence of laterality increased as dilatation proceeded. It was larger on the left side in 9 out of 11 cases. We have no reasonable explanation of this tendency. There was one case with a tumor which was verified by enhanced CT. There were five cases with brain anomalies.

Adolescent↗
PubMed1979

[Computed tomography in crossed aphasia (author's transl)].

Crossed aphasia, first described by Bramwell, is aphasia due to the hemispheric damage on the side of handedness. Crossed aphasia in a dextral is rare, and in Japan, there have not been more than ten cases in which the lesion is localized clearly. The cases reported till now have been verified mainly by necropsy. However, the time lag between the appearance of aphasia and the necropsy may affect the conclusion subtly. We consider that computed tomography (CT) can obtain almost the same findings as that by necropsy. However, at present there have been few cases diagnosed by CT except two cases reported by April et al. and Wechsler. We have reported a 47-year-old man in a dextral, who shows left hemiparesis and Broca's aphasia. His lesion is diagnosed by cerebral angiography and CT as the right hemisphere infarction due to right middle cerebral artery occlusion. CT localizes the lesion on the right hemisphere mainly sited deep region and sited wedge shaped cortical area of the fronto-parietal region. On the other hand, it localizes no lesion on the left hemisphere. CT in aphasia has been already reported by Hayward et al. In their report they concluded that correlation of lesion located by CT with aphasia type supported Geschwind's concept of aphasia. In this report we have discussed CT in crossed aphasia analysing our case and the two cases by April et al. and Wechsler. Three cases including our case are all Broca's aphasia, and we compare the lesion location of these three cases with Hayward's lesion located on Broca's aphasia. As the result of this, we can draw the conclusion that the lesion location by CT of these three cases and that of Hayward's report are almost symmetric.

Aphasia↗
PubMed1979

Variation of two forms of DNA polymerase-alpha during a HeLa cell cycle.

HeLa cells contain two forms of DNA polymerase-alpha (P-I and P-II) with varied affinity to DNA, separable on a DNA-cellulose column. The activity of each form was followed during a cell cycle of synchronized culture of the HeLa cells. P-I was recovered from the nuclear extract and P-II from the cytoplasmic fraction. The P-I activity remained at a low level during M to G1 phase until a marked increase between late G1 and S phases, while P-II activity increased gradually throughout the period. Both activities attained their highest level at mid-S phase and then the P-I activity declined more rapidly than the P-II. Addition of hydroxyurea at mid-S phase inhibited the decrease of both enzyme activities. The enzyme activity of nuclear extract from S phase cells was not inhibited by mixing with extract from M phase cells. When the cytoplasmic fraction from M phase cells was chromatographed on a DNA-cellulose column, single activity peak was observed at the position of P-II. These results suggest that the decrease in P-I activity is neither due to the presence of an inhibitor nor to mere release of the enzyme from chromosomes.

Cell Cycle↗
PubMed1978

Exposure of DNA bases induced by the interaction of DNA and calf thymus DNA helix-destabilizing protein.

The reaction of chloroacetaldehyde with adenine bases in DNA to give a fluorescent product was used to study the availability to intermolecular reaction of positions 1 and 6 of adenine in DNA complexes with calf thymus DNA helix-destabilizing protein. No inhibition of this reaction was observed when heat-denatured DNA was complexed with the protein at a protein/DNA weight ratio of 10:1, compared to free DNA. On the contrary, the same reaction was inhibited markedly for denatured DNA in the presence of calf thymus histone HI at protein/DNA weight ratio of 2:1. Furthermore, the exchange rate for hydrogens of amino and imide groups of DNA bases in DNA strands with deuterium in the solvent was totally unaffected upon complexing of DNA with the DNA helix-destabilizing protein as examined by stopped-flow ultraviolet spectroscopy. These results indicate that the DNA helix-destabilizing protein forms a complex with single-stranded DNA, leaving DNA bases uncovered by the protein. The fluorescence intensity of DNA pretreated with chloroacetaldehyde was amplified by nearly 3-fold upon addition of the DNA helix-destabilizing protein. The possibility of "unstacking" of DNA bases induced by the protein is discussed.

Acetaldehyde↗
PubMed1977

Further evidence of the presence of progesterone-binding proteins in female rat hypothalamus.

Utilizing techniques of Sephadex G-200 column chromatography, sucrose density gradient ultracentrifugation and dextran-coated charcoal adsorption, the characterization of progesterone-binding proteins was attempted in cytosols obtained from the medial basal hypothalamus including the median eminence, the remaining hypothalamus and the cerebral cortex of ovariectomized estrogen-primed rats. Ater incubation of the medial basal hypothalamic cytosol with 3H-progesterone in the absence or in the presence of various unlabeled steroids, a specific progesterone-binding protein was found in the 7 S region with its binding capacity of approximately 2 X 10(14) moles per mg protein and dissociation constant of approximately 6 X 10(-9) M. No specific binding was, however, found in the remaining hypothalamus and the cerebral cortex.

Animals↗