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T Shinagawa

Publications and source records attributed to T Shinagawa.

At least 55 records · Page 3Linked to original sources
PubMed1994

A spontaneous internal deletion of the c-myb protooncogene enhances transcriptional activation in bovine T lymphoma cells.

Three double negative (BoCD4-, BoCD8-) bovine T cell lines, BTL-PC3, BLT2, and Pr2181, which have been established from bovine lymphosarcomas, were examined for expression and molecular function of bovine c-myb genes. BTL-PC3 expressed 4.0- and 3.6-kilobase c-myb transcripts, and BLT2 and Pr2181 expressed a 3.8-kilobase c-myb message. The c-Myb protein (75 kDa) was detected in Pr2181 but not as a clear band in BLT2, while BTL-PC3 exhibited a 65-kDa c-Myb band in immunoprecipitation tests with anti-Myb antiserum. Nucleotide sequences for c-myb cDNA clones from BTL-PC3 and BLT2 indicated that the predicted bovine wild-type c-Myb from BLT2 consists of 640 amino acids whereas that from BTL-PC3 consists of 555 amino acids lacking 85 internal amino acids. This deleted DNA region (255 base pairs consisting of 85 amino acids) corresponds to the human genomic exon 9 encoding a negative regulatory domain in the c-myb gene. Upon cotransfections with reporter plasmids containing myb binding sites, the internally deleted c-Myb exhibited a 3-fold higher transcriptional activity than the wild-type c-Myb in chloramphenicol acetyltransferase assays. These results indicate that internal DNA deletion in the c-myb gene is directly involved in the enhancement of transcriptional activation in bovine T lymphoma cells.

Amino Acid Sequence↗
PubMed1994

Oligonucleotide probe design--a new approach.

The use of oligonucleotides for gene amplification, as diagnostic probes or antisense-based drugs can be optimized by minimizing the possibility of nonspecific hybridization.

Base Sequence↗
PubMed1994

Protein kinase C inhibitors enhance differentiation of rat adipocyte precursor cells in serum-free culture.

The involvement of protein kinase C in differentiation of rat adipocyte precursor cells in serum-free culture was evaluated by using various protein kinase inhibitors. Induction of adipose conversion, which was maximal after 10 days of culture in the presence of 5 micrograms/ml insulin, 10 micrograms/ml transferrin, and 200 pM triiodothyronine, was inhibited by the addition of protein kinase C inhibitors, H-7 and staurosporine, in a dose-dependent fashion with the maximal effect at 10 microM and 10 nM, respectively. Inhibition of adipocyte differentiation by 12-O-tetradecanoylphorbol 13-acetate (10(-8) M), an activator of protein kinase C, was reversed by a concomitant addition of either 10 microM H-7 or 10 nM staurosporine. HA1004, a potent inhibitor of cAMP- and cGMP-dependent protein kinases, with minimal inhibitory activity on protein kinase C, did not affect adipose conversion. Furthermore, H-89, another isoquinoline derivative with a selective inhibitory action on cAMP-dependent protein kinase, was without effect on cellular differentiation. These results indicate that the potentiation of adipogenesis by H-7 and staurosporine is mediated by suppression of protein kinase C and that protein kinase C is involved in adipocyte differentiation in an inhibitory fashion.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1994

Putative bovine B cell lineage tumor in sporadic bovine leukosis.

Two calves (C924 and C928) clinically identified as suffering from the calf type of sporadic bovine leukosis (SBL) were examined for immunophenotypical distribution of their peripheral blood lymphocytes (PBL) with T cell or B cell specific monoclonal antibodies (mAbs). Flow cytometric profile analysis indicated that both calves possessed a high population of MHC class II positive cells and a low population carrying T cell associated markers. More than 93% of the PBL of C928 were positive for MHC class II and BoCD5, but were not IgM positive, indicating that clonal tumor cells (MHC-II+, BoCD5+ and IgM-) accounted for most of the PBL of C928. A tumor cell line, BLC3, established from calf C924 in nude mice was examined for immunophenotype, DNA rearrangement of immunoglobulin (Ig) genes and expression of cellular oncogenes c-abl, c-myc and c-myb. BLC3 showed a characteristic profile, being MHC class I and MHC class II positive, but without T cell associated markers. Although the rearranged configuration in the Ig loci was not clearly found in Southern blot analysis using sheep Ig probes, steady-state levels of c-myb transcripts were detected in tumor cell line BLC3 by Northern blot hybridization. Taken together, our data show that the calf type of SBL found in these two calves is induced by immature pre-B cells, including tumor cell line BLC3 established in nude mice.

Animals↗
PubMed1994

Characterization of monoclonal antibodies against sporadic bovine leukosis cell lines.

We report here distributions of antigens expressed on sporadic bovine leukosis (SBL) cells by a total of 38 monoclonal antibodies (mAbs) directed against three different types of SBL-cell lines, BLT2 (thymic type), BTL-PC3 (calf type) and BLS1 (skin type). Most mAbs had high reactivities with some bovine lymphoma cell lines and less reactivity with normal lymphocytes except for some peripheral blood mononuclear cells (PBM) in cattle and certain other species. They were more reactive with cultured T-cell line BTL-PC3 and B-cell lines, BL312 and KU-1, than naturally occurring lymphoid tumor cells. Among the 38 mAbs, 27 was determined the molecular weights of their recognized antigens in Western blot analyses. A mAb C419 had high reactivity with lymphoma cell lines but no reactivity with normal lymphocytes, indicating that it recognizes tumor-associated antigens of SBL.

Animals↗
PubMed1994

Monoclonal antibody S37 induces apoptosis in bovine T lymphoma cells.

Influences of 38 monoclonal antibodies (mAbs) on the growth of bovine T lymphoma cells (BTL-27) were examined. One of them, S37, inhibited the cell growth strikingly when it was added to the cultures. S37-treated cells showed DNA fragmentation containing approximately 200-base pair multiple patterns and chromatin condensation. This evidence suggested that mAb S37 induced apoptosis in BTL-27 cells.

Animals↗
PubMed1994

[A case of desmoplastic infantile ganglioglioma].

We have been experienced a rare case of large supratentorial neuroepithelial tumor with a subdural cyst originated from the left fronto-parietal lobe in a 14-month-old boy. The tumor was characterized by its voluminous size, a leptomeningeal growth pattern with intense desmoplasia and divergent astrocytic and ganglionic differentiation. Schwann cell differentiation and melanocytes were also minutely demonstrated. These histological findings are characteristic of desmoplastic infantile gangliogliomas, reported by VandenBerg et al in 1987. And this tumor tissue architecture strongly suggests the hamartomatous nature, rather than the ordinary neoplastic lesion.

Brain↗
PubMed1993

Origin of a sperm motility inhibitor from boar seminal plasma.

We have investigated the origin of the sperm motility inhibitor (SPMI) from boar seminal plasma. SPMI was measured by its capacity to inhibit the motility of demembranated spermatozoa and by an enzyme-linked immunosorbent assay (ELISA). Among the various reproductive and now reproductive tissues and fluids tested, only the seminal vesicle fluid and seminal plasma contained significant amounts of SPMI biological activity and SPMI antigen. Like other seminal vesicle fluid proteins, SPMI is diluted 6- to 8-fold upon ejaculation. By immunohistochemical detection at the light microscope with antibodies obtained from rabbits immunized with SPMI purified from boar seminal plasma, SPMI was found in the cytosol and/or on the plasma membrane bordering the lumen of the seminal vesicles. At the electron microscope level, SPMI appeared to be present only on the surface of the secretory cells. The data indicate that SPMI originates from a single tissue, the seminal vesicle, and suggest that only the mature form present on the luminal surface of the gland can react with the antibody generated from rabbits immunized with the secreted form of SPMI.

Adenosine Triphosphatases↗
PubMed1993

Interleukin 6 production by peripheral blood mononuclear cells in patients with chronic hepatitis B virus infection and primary biliary cirrhosis.

IL-6 production by peripheral blood mononuclear cells (PBMC) was studied in patients with chronic hepatitis B virus (HBV) infection and primary biliary cirrhosis (PBC) using the ELISA method. Spontaneous production of IL-6 was significantly increased in patients with HBeAg+ chronic hepatitis (CH). The cultures stimulated with lipopolysaccharide and lectin-free interleukin-2 (IL-2) showed enhanced IL-6 production both in controls and all patient groups compared with culture without any stimulation. IL-6 production in response to IL-2 was higher in patients with HBeAg+ CH and PBC than in controls. In PBMC with increased IL-6 production, monocyte function was increased in patients with HBeAg+ CH and PBC, while B cells from PBC showed elevated response to Staphylococcus aureus Cowan 1. IL-6 production in the presence of HBeAg was greater in anti-HBe+ patients than in HBeAg+ ones. These results suggest that IL-6 response is involved in the immune response in patients with chronic liver disease.

Adult↗
PubMed1992

Purification and characterization of human truncated prorenin.

Posttranslational processing of enzymatically inactive prorenin to an active form participates in the control of the activity of a key system involved in blood pressure regulation, growth, and other important functions. The issue is complicated because renin can be produced by a number of tissues throughout the body, in addition to the kidney, but the mechanism by which they process prorenin to renin is unknown and difficult to determine because of the small amounts of renin present. In the juxtaglomerular cell of the kidney, a 43 amino acid prosegment is cleaved from the amino terminus of prorenin to generate renin of molecular weight 44,000 [Do, Y. S., Shinagawa, T., Tam, H., Inagami, T., & Hsueh, W. A. (1987) J. Biol. Chem. 262, 1037-1043]. Using human uterine lining or a recombinant human prorenin system, we employed the same approach as that used in kidney, ammonium sulfate precipitation at pH 3.1 followed by pepstatin and H-77 affinity chromatography or gel filtration, to purify to homogeneity a 45,500-MW totally active renin. The specific activity of the active truncated prorenin was 850 Goldblatt units (GU)/mg of protein for chorion-decidua renin and 946 GU/mg of protein for recombinant renin, both similar to that reported for pure human renal renin. Both forms of renin cross-reacted with an antibody generated against 44,00-MW pure human renal renin and with an antibody generated against a peptide identical to the carboxy-terminal one-third of the prosegment.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1992

Isoelectric point of an ion-penetrable membrane.

The surface potential of an ion-penetrable planar membrane is calculated for the case in which acidic and basic groups are present in the membrane. It is found that when both acidic and basic groups are not uniformly distributed in the direction normal to the membrane, the isoelectric point (the pH value at which the surface potential becomes zero) of the membrane varies with the electrolyte concentration, whereas if both groups are uniformly distributed, the isoelectric point is independent of the electrolyte concentration. As a simple example, we treat a membrane consisting of two layers, in which acidic groups are distributed in the outer layer and basic groups are in the inner layer. Simple equations determining the membrane surface potential as a function of pH and electrolyte concentration and the dependence of the isoelectric point on the electrolyte concentration are presented.

Chemical Phenomena↗
PubMed1992

Localisation of intrahepatic interleukin 6 in patients with acute and chronic liver disease.

AIM: To evaluate the role of local interleukin 6 (IL-6) in the pathogenesis of acute and chronic liver disease. METHODS: The cellular site of IL-6 in cryostat sections of liver from 31 patients with liver disease was examined using indirect immunofluorescence with a monoclonal antibody. RESULTS: IL-6 staining in sinusoidal endothelial cells was very noticeable and diffusely distributed in the lobules of specimens of acute viral hepatitis. IL-6 expression in endothelial cells, particularly in necrotic areas of hepatocytes, was increased and was accompanied by enhanced expression in Kupffer cells. In contrast, IL-6 staining in infiltrating mononuclear cells was prominent in portal tracts, and the numbers of cytokine positive cells were greater in specimens of chronic active hepatitis compared with chronic persistent hepatitis. In non-specific reactive hepatitis intrahepatic expression of IL-6 was minimal, while in alcoholic liver fibrosis the cytokine distribution in the lobules was similar to that of acute viral hepatitis. CONCLUSIONS: These results indicate that locally produced IL-6 contributes to the inflammatory process and immunological response in acute and chronic liver disease.

Acute Disease↗