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Biomedical subjects

T Matsui

Publications and source records attributed to T Matsui.

At least 1,009 records · Page 56Linked to original sources
PubMed1983

Induction of superovulation in prepubertal female rats by anterior pituitary transplants.

Transplants of 26-day-old rats of an anterior pituitary gland from adult intact or castrated male, 20-day-old or adult ovariectomized female donors (all of which contained large amounts of FSH) resulted in superovulation in recipients on the morning of Day 29. Transplants of the gland from 20-day-old males and adult cyclic females could not advance the time of first ovulation or induce superovulation. In the rats in which superovulation could be induced, a marked increase in plasma FSH was noted in recipients shortly after transplantation and the high levels of plasma FSH were maintained until at least 12 h after grafting. These rats also showed preovulatory surges of LH and FSH 54 h after grafting. No obvious elevation of plasma FSH was noted over 72 h in recipients in which superovulation could not be induced. These findings suggest that the final maturation of follicles for superovulation is induced by a transient release of a large amount of FSH from the grafted pituitary gland and that the sex of the pituitary donor has no bearing on this phenomenon.

Animals↗
PubMed1983

Effects of human fibroblast interferon on human gliomas transplanted into nude mice.

Daily intratumor injection of human fibroblast interferon (HuIFN-beta) resulted in significant growth inhibition of human gliomas transplanted into nude mice. Light and electron microscope examinations were conducted to estimate the efficacy of HuIFN-beta. A 29-day daily treatment with HuIFN-beta induced complete regression of oligodendroglioma KG-1--a slowly growing tumor line positive for S-100 protein and negative for glial fibrillary acidic protein (GFAP)--in 9 out of 10 mice receiving 6 X 10(5) IU and 6 out of 9 given 1 X 10(5) IU. In mice with glioblastoma multiforme TMIMS-583, which showed more rapid growth and was positive for GFAP, dose-dependent growth inhibition was observed during 23 days of HuIFN-beta administration. Pathological changes of TMIMS-583 induced by HuIFN-beta were characterized by a decrease of the metaphase tumor cells, by enhanced degeneration of tumor cells with stromal reaction and round cell infiltrates, and by prominence of multinuclear giant cells containing glial filaments. Tumor weights were well correlated with the number of tumor cells in the metaphase (r = 0.89).

Adult↗
PubMed1983

Natural cytotoxic reactivity of peripheral blood lymphocytes from digestive tract cancer patients against a colon cancer cell line and virus-infected HeLa cells.

The natural killer (NK) activity of peripheral blood lymphocytes of gastric cancer patients in all pathological stages from I to IV was less than that of healthy persons or patients with benign diseases. However, there was no significant difference in the antibody-dependent cellular cytotoxicity (ADCC) of cancer patients and healthy individuals, and the correlation between NK and ADCC activities was somewhat lower in cancer patients than in healthy persons. The peripheral blood lymphocytes from digestive tract cancer patients were divided into two fractions on the basis of low affinity erythrocyte (E)-rosette formation. The NK activity of the low affinity E-receptor negative fraction from cancer patients was significantly lower than that of the same fraction from healthy persons. The binding of lymphocytes with target cells is considered to be a first step of natural killing. In cancer patients, there was a decrease in the target-binding capacity of lymphocytes in both fractions. Therefore, the decreased NK activity of cancer patients appeared to be related to a reduced target-binding capacity.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1982

Paradoxical anti-leukemic effects of plant-derived tumor promoters on a human thymic lymphoblast cell line.

Three different diterpen polyols and the teleocidin have antileukemic effects on the human thymic leukemia cell line HPB-ALL by inducing phenotypic differentiation. We tested TPA (phorbol esters), mezerein (daphnane), milliamin (ingenol ester) and teleocidin B (teleocidins) as representative of the chemical structure of each principle and found that these agents have the similar biological activity of inducing phenotypic differentiation in HPB-ALL cells. Moreover, competitive binding of [3H]PDB to cell-surface receptors was significantly inhibited by these agents; n-butyrate and phorbol per se did not inhibit the binding of [3H]PDB. Despite differences in the structure of the principles, these agents may have similarly acting side-chain structures.

Alkaloids↗
PubMed1982

In vitro accurate initiation of transcription on the adenovirus type 2 IVa2 gene which does not contain a TATA box.

In vitro initiation of transcription has been studied on the IVa2 gene of the adenovirus type 2 ( Ad2 ) which is expressed at intermediate time after infection. This gene does not contain a TATA box around 30 bp upstream from the cap site. By analyses of the in vitro runoff products by size and by single strand nuclease protection mapping, it was concluded that the in vitro initiation occurred accurately at two in vivo cap sites with low but detectable efficiency. By using cloned IVa2 DNA, which is free from the major late promoter, it was suggested that the low efficiency of the in vitro initiation on the IVa2 gene may not be due to close location of the two genes but may rather reflect the efficiency of the promoter itself. The cell-free extracts from both uninfected and infected HeLa cells supported the accurate initiation of transcription in vitro with almost the same efficiency. In addition, the cell free extract directed an artificial initiation of transcription in vitro by recognizing a TATA box located 140 bp upstream from the cap sites.

Adenoviruses, Human↗
PubMed1982

Determination of the transcription initiation site of Tetrahymena pyriformis rDNA using in vitro capping of 35S pre-rRNA.

Approximately 700 nucleotide sequences surrounding the transcription initiation site were determined with a cloned rDNA fragment of Tetrahymena pyriformis and the transcription initiation site was localized on these sequences using purified 35S pre-rRNA. A considerable portion of the 35S pre-rRNA was found to be capped in vitro. The 32P-labeled, capped 35S pre-rRNA, on nucleus P1 protection mapping, gave the protection band which is identical in size with that obtained with bulk 35S pre-rRNA. Both reverse transcription extension and nuclease P1 mapping localized the 5'-end of the 35S pre-rRNA at the same adenine nucleotide, 496 base pairs upstream from the HindIII site of the cloned rDNA fragment. Furthermore, sequencing of the 5'-terminal region of the in vitro capped 35S pre-rRNA unambiguously confirmed the above result. The strategy adopted in the present experiment could serve as a general procedure for determining the transcription initiation point even in cases where the concentration of the primary transcript is low.

Animals↗
PubMed1982

The localization of the motor neurons innervating the cricothyroid muscle in the adult dog by the fluorescent retrograde axonal labeling technique.

Injection of 4'6-diamidino-2-phenylindol 2 HCl (DAPI) into the cricothyroid muscle of the adult dog resulted in blue fluorescence of cells found exclusively in the rostral part of the ipsilateral nucleus ambiguus. These labeled neurons on the average extended 1.8 mm from the level just caudal the facial nucleus to the caudal extension. In the rostral tip of the nucleus, labeled cells were located in a scattered ventral group of larger neurons of the nucleus.

Animals↗
PubMed1982

A denuded "turn-over" deltopectoral flap combined with a latissimus dorsi myocutaneous flap in the repair of extensive radionecrosis of the chest wall.

For a one-stage repair of large and deep radionecrotic ulcers over the chest wall, we have used a denuded "turn-over" deltopectoral flap combined with a latissimus dorsi myocutaneous flap. With this technique we can easily cover a defect measuring over 20 x 20 cm. The deformity of the donor site on the contralateral infraclavicular region is minimal. Three illustrative cases are presented.

Adult↗
PubMed1982

Purification and characterization of a chymotrypsin-like enzyme from sperm of the sea urchin, Hemicentrotus pulcherrimus.

A chymotrypsin-like enzyme has been purified from sperm of the sea urchin, Hemicentrotus pulcherrimus, using tryptophan methyl ester (TrpOMe) linked to Sepharose 4B as an affinity column for chromatography and gel filtration. The isolated enzyme preparation is homogeneous in sodium dodecylsulfate/polyacrylamide gel electrophoresis, the estimated molecular weight being 18,500-19,000. This enzyme hydrolyses N-acetyl-L-tyrosine ethyl ester (AcTyrOEt) and N-benzoyl-L-tyrosine ethyl ester (BzTyrOEt); the optimal pH is 8.0. It does not hydrolyse N-benzoyl-L-arginine ethyl ester, N-alpha-toluenesulfonyl-L-arginine methyl ester, N-alpha-benzoyl-DL-arginine-p-nitroanilide, hippuryl-L-arginine or hippuryl-L-phenylalanine. The Michaelis constants for AcTyrOEt and BzTyrOEt are 0.05 mM and 0.0106 mM, respectively. The enzyme activity is inhibited completely by phenylmethylsulfonyl fluoride (PhMeSO2F), chymostatin and L-1-tosylamido-2-phenylethyl chloromethyl ketone (TosPheCH2Cl), and partially by soybean trypsin inhibitor and N-alpha-p-tosyl-L-lysine chloromethyl ketone (TosLysCH2Cl). The enzyme is activated by CaCl2, MgCl2, NaCl and KCl, and loses its activity in 5 min at 67 degrees C. It digests the jelly coat and vitelline layer, not the fertilization membrane. The microvilli of unfertilized eggs elongate and decrease in number as the vitelline layer lyses. The vitelline layer lytic activity is inhibited completely by PhMeSO2F, TosPheCH2Cl, and chymostatin, and partially by soybean trypsin inhibitor, TosLysCH2Cl, and alpha 1-antitrypsin. We have confirmed by transmission electron microscopy that our chymotrypsin-like enzyme completely digests the vitelline layer. A result implying release of this enzyme from the acrosome vesicle is also reported.

Acrosome↗