Biomedical subjects

Y Watanabe

Publications and source records attributed to Y Watanabe.

At least 19 recordsLinked to original sources

PubMed1992

Different antigenic nature in apparently healthy women with high serum CA 125 levels compared with typical patients with ovarian cancer.

BACKGROUND: CA 125 is a representative ovarian cancer-associated antigen defined by monoclonal antibody OC125. Recently, monoclonal antibodies were produced (designated 130-22 and 145-9) that were reactive with CA 125 but bound to a separate epitope named CA 130. There was a close correlation between serum CA 125 and CA 130 values in most instances. However, among more than 8000 serum samples, 5 apparently normal women had high serum CA 125 values, despite having normal CA 130 values. In this study, the antigenic nature of these five women was investigated. METHODS: Using gel chromatography, the molecular masses of CA 125 and CA 130 were estimated that were found in the five women with false-positive CA 125 values. The sera were examined using double-determinant assays combining iodine-125-labeled OC125 or iodine-125-labeled 130-22 with OCI25-coated or 145-9-coated beads. RESULTS: The molecular masses of both CA 125 and CA 130 were estimated as greater than 1000 kilodaltons (KD); the CA 130 mass from one of the five women with an abnormal CA 125 level was approximately 200 KD using gel chromatography. Using the double-determinant assays that combined iodine-125-labeled OC125 or iodine-125-labeled 130-22 with OC125-coated or 145-9-coated beads, high radioactivity was found only in the homologous assay using iodine-125-labeled OC125 with OC125-coated beads. These results suggest that the antigenic nature of CA 125 found in apparently healthy women differs from that found in patients with ovarian cancer and that CA 130 epitopes are not present. CONCLUSIONS: Measurement of serum CA 130 concentrations may be useful for excluding women with falsely elevated CA 125 values.

Acrylic Resins↗

PubMed1992

In vivo phosphorylation of the 30-kDa protein of tobacco mosaic virus.

The 30-kDa protein of tobacco mosaic virus, which is involved in cell-to-cell movement function, is phosphorylated in tobacco protoplasts. To investigate which portion of the protein is phosphorylated we inoculated several truncated 30-kDa protein mutants into protoplasts and determined whether or not those truncated proteins are phosphorylated. The results showed that amino acid residues 234-261 of the 30-kDa protein are required for this phosphorylation.

Amino Acid Sequence↗

PubMed1992

Effects of glycine and structurally related amino acids on generation of long-term potentiation in rat hippocampal slices.

The effects of glycine and structurally related amino acids, serine, alanine and valine, on generation of long-term potentiation (LTP) of evoked potentials were investigated in the CA1, CA3 and dentate regions of rat hippocampal slices. In the Schaffer collateral-CA1 pyramidal cell synapses and in the perforant path-dentate granule cell synapses, glycine (5 x 10(-4) M) significantly enhanced the short-term potentiation (STP) induced by subthreshold tetanic stimulation, without affecting baseline responses. The effects of glycine resulted in generation of LTP in both synapses. On the other hand, glycine did not influence STP induced by subthreshold tetanus in the mossy fiber-CA3 pyramidal cell synapses. These results suggest that exogenous glycine can facilitate the generation of LTP in the CA1 region and in the dentate gyrus but not in the CA3 region. In the CA1 region and the dentate gyrus, D- and L-serine and D-alanine (10(-3) M) also showed the LTP-facilitating effects in a similar manner to glycine, but D- and L-valine had no effect on LTP generation. Furthermore, glycine and D-serine, but not L-valine, enhanced NMDA receptor-mediated synaptic responses in the absence of extracellular Mg2+. Together, these results make it probable that exogenously applied glycine and related amino acids facilitate the generation of LTP in the CA1 and dentate region by activating the glycine modulatory sites associated with NMDA receptors.

Alanine↗

PubMed1992

Tianeptine attenuates stress-induced morphological changes in the hippocampus.

Repeated 6-h daily restraint stress over 21 days reduces length and number of branch points of hippocampal CA3c pyramidal dendrites in the hippocampal formation of adult male rats. This effect is mimicked by daily injections of 40 mg/kg corticosterone. Daily treatment with tianeptine (15 mg/kg) prior to stress sessions or the corticosterone treatment prevented these effects of stress or corticosterone, respectively. Tianeptine treatment did not prevent the effects of stress to increase adrenal/body weight ratio, nor did it prevent the effects of stress to decrease body weight gain, indicating that its actions are not mediated solely by effects on stress-induced secretion of corticosterone. Because tianeptine is known to enhance neural uptake of serotonin, these results suggest that the serotonergic system may be involved in modulating stress and corticosterone effects on dendritic morphology.

Animals↗

PubMed1992

A murine model for antibody-directed targeting of vascular endothelial cells in solid tumors.

An attractive approach to the therapy of solid tumors would be to target cytotoxic agents or coagulants to the vasculature of the tumor rather than to the tumor cells themselves. This strategy has 3 advantages: (a) it should be applicable to many types of solid tumors because all require a blood supply for survival and growth; (b) the target endothelial cells are directly accessible through the blood and are normal cells, making the outgrowth of resistant mutants unlikely; and (c) there is an in-built amplification mechanism because thousands of tumor cells are reliant on each capillary for nutrients and oxygen. Despite its theoretical attractions, the approach of tumor vascular targeting has not been testable because antibodies that recognize tumor vascular endothelial cell antigens with adequate specificity are currently not available. In this study, we developed a model system in which to investigate the antibody-directed targeting of vascular endothelial cells in solid tumors in mice. A neuroblastoma transfected with the mouse interferon-gamma gene, C1300(Mu gamma), was grown in antibiotic-treated BALB/c nude mice. The interferon-gamma secreted by the tumor induces the expression of major histocompatibility complex Class II antigens on the tumor vascular endothelium. Class II antigens are absent from the vasculature of normal tissues, although they are present on B-lymphocytes, cells of monocyte/macrophage lineage, and some epithelial cells. Anti-Class II antibody administered i.v. strongly stains the tumor vasculature, whereas an antitumor antibody directed against a major histocompatibility complex Class I antigen of the tumor allograft produces classical perivascular tumor cell staining. This model should enable the theoretical superiority of tumor vascular targeting over conventional tumor cell targeting to be tested.

Animals↗

PubMed1992

Monoclonal antibody against the common beta subunit (beta c) of the human interleukin-3 (IL-3), IL-5, and granulocyte-macrophage colony-stimulating factor receptors shows upregulation of beta c by IL-1 and tumor necrosis factor-alpha.

High-affinity receptors for human granulocyte macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), and IL-5 are composed of two distinct subunits, alpha and beta. Each receptor has its own ligand-specific alpha subunit, and the three receptors share the common beta subunit, beta c. Using a transfectant of NIH3T3 cells expressing the high-affinity human GM-CSF receptor, monoclonal antibodies (MoAbs) against beta c were generated. These MoAbs specifically bound to cells bearing beta c and immunoprecipitated the beta c protein of 120 Kd. Using these MoAbs, expression of beta c was examined. It is known that IL-1 augments the proliferative response of a human factor-dependent hematopoietic cell line TF-1 to either GM-CSF, IL-3, or IL-5, and that it upregulates the high-affinity receptors for GM-CSF, IL-3, and IL-5. Antibody binding and immunoprecipitation demonstrated that IL-1 increased cell surface expression of beta c. This enhancement by IL-1 was accompanied by an increased level of beta c mRNA. In addition, we found that tumor necrosis factor-alpha (TNF-alpha) also increased the expression of beta c, although it did not augment the proliferative response of TF-1 to GM-CSF, IL-3, and IL-5.

3T3 Cells↗

PubMed1992

In situ DNA-protein binding: a novel method for detecting DNA-binding activity of transcription factor in brain.

A novel method, in situ DNA-protein binding (in situ DPB), was developed to detect the distribution and DNA-binding activity of AP-1 and Sp1 binding proteins in situ. The regional distribution of AP-1 binding protein in mouse brain was different from that of Sp1. Antibody against the DNA-binding domain of Jun protein markedly reduced the AP-1 but not the Sp1 binding activity. The binding activity of AP-1 probe increased markedly in the brain after administration of methamphetamine. These results suggest that the in situ DPB is convenient and sensitive for detecting the distribution and the DNA-binding activity of transcription factors in situ.

Animals↗

PubMed1992

[Pregnancy in Cushing's syndrome].

Pregnancy in cases of Cushing's syndrome is rare. A pregnant patient with Cushing's syndrome due to an adrenal adenoma who was diagnosed in the third trimester is described. She underwent conservative treatment for Cushing's syndrome and delivered a normal infant by Caesarean section. Currently, 121 pregnancies in 97 patients have been reported, but a principle for the treatment of the mother and fetus has not yet been established. We reviewed pregnancy in Cushing's syndrome based on the world literature and evaluated the choice of treatment to take. In the first trimester of pregnancy, therapeutic abortion or surgical treatment, such as adrenalectomy or resection of the pituitary tumor in Cushing's syndrome, is recommended for patients with severe hypercorticism (plasma cortisol > or = 30 micrograms/dl, urinary 17-OHCS > or = 15 mg/day, urinary free cortisol > or = 1000 micrograms/day), while conservative treatment is recommended for patients with mild hypercorticism (plasma cortisol < 30 micrograms/dl, urinary 17-OHCS < 15 mg/day, urinary free cortisol < 1000 micrograms/day). In the second trimester of pregnancy, surgical treatment is recommended for patients with severe hypercorticism, while conservative treatment is recommended for patients with mild hypercorticism. In the third trimester of pregnancy, Caesarean section is recommended for most cases. Drug treatments such as with metyrapone should be limited to patients showing severe hypercorticism or a maternal high risk who have contraindications to surgical treatment.

Adenoma↗

PubMed1992

Synthesis and biological properties of 2-substituted myo-inositol 1,4,5-trisphosphate analogues directed toward affinity chromatography and photoaffinity labeling.

A series of myo-inositol 1,4,5-trisphosphate analogues with the 2-acyl substituents p-aminobenzoyl (7), p-azidobenzoyl (8), 4-(5-[2-(benzamido)ethyl]-2-hydroxyphenylazo)benzoyl (9), and cis,trans-4-aminocyclohexylcarbonyl (10) were synthesised and examined for their effects on the 5-phosphatase, the 3-kinase, the tritiated trisphosphate-binding activity, and the Ca(2+)-releasing activity. Each analogue inhibited the hydrolysis of D-[5-32P]Ins(1,4,5)P3 and the phosphorylation of D-[3H]Ins(1,4,5)P3, catalysed by erythrocyte ghosts and brain cytosol, respectively. The analogues acted as full agonists in releasing Ca2+ from permeabilised cells and also inhibited the binding of D-[3H]Ins(1,4,5)P3 to cerebellum microsomes. The analogues 7 and 10 were utilised for immobilisation of the trisphosphate on Sepharose and the subsequent affinity chromatography effected purification of the above proteins. A photoaffinity probe, the appendage of which acted as the photoaffinity probe as well as a non-radioactive molecular marker, was also derived from the analogue 7.

Animals↗

PubMed1992

Activation of human CD4+CD45RA+ T cells by chrysotile asbestos in vitro.

Chrysotile asbestos stimulates T lymphocyte subsets. Cell surface CD4 or CD45RA expression in peripheral blood mononuclear cells (PBMC) was downregulated after incubation with chrysotile asbestos in vitro temporarily. The percentage of CD4+CD45RA+ cells and mean fluorescence intensity in CD4 or CD45RA decreased after incubation with asbestos and returned to the original level after 24 h of incubation, which suggests that chrysotile asbestos activates CD4+CD45RA+ cells. No change was observed in CD29 expression. An increased percentage of IL-2R positive cells and an elevated intracellular Ca++ level were also indicative of the activation of PBMC by chrysotile asbestos.

Antigens, CD↗

PubMed1992

Calmodulin cDNAs from two species of Tetrahymena.

We describe the isolation and characterization of cDNAs encoding calmodulins of Tetrahymena thermophila and Tetrahymena pyriformis. It reveals that the deduced amino acid sequences of both calmodulins are precisely the same.

Amino Acid Sequence↗

PubMed1992

Calvasculin, an encoded protein from mRNA termed pEL-98, 18A2, 42A, or p9Ka, is secreted by smooth muscle cells in culture and exhibits Ca(2+)-dependent binding to 36-kDa microfibril-associated glycoprotein.

Calvasculin, an EF-hand protein with a molecular mass of 11 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, is present abundantly in bovine aorta (Watanabe, Y., Kobayashi, R., Ishikawa, T., and Hidaka, H. (1992) Arch. Biochem. Biophys. 292, 563-569). This protein is synthesized constitutively by bovine aortic smooth muscle (BASM) cells and rat embryo fibroblast 3Y1 cells in culture. We discovered that calvasculin was secreted by BASM cells and 3Y1 cells. Immunofluorescence staining of BASM cells showed a granular distribution for calvasculin that was typical of a secreted protein. This protein bound with an extracellular matrix protein, 36-kDa microfibril-associated glycoprotein (36-kDa MAP), in a Ca(2+)-dependent manner in vitro. A stoichiometry analysis showed that the 36-kDa MAP bound 2.2 calvasculin eq/mol of protein. Solid-phase binding assays indicated a preferential affinity of native calvasculin for 36-kDa MAP among the extracellular matrices in a Ca(2+)-dependent manner. These results suggest that calvasculin, intracellular Ca(2+)-binding protein, is released to the extracellular space and binds with 36-kDa MAP.

Animals↗

PubMed1992

Stress induces atrophy of apical dendrites of hippocampal CA3 pyramidal neurons.

The hippocampus is vulnerable to the damaging actions of insults such as transient ischemia and repetitive stimulation, as well as repeated exposure to exogenous glucocorticoids. This study investigated effects of a repeated psychological stressor, restraint, on the CA3 pyramidal neurons which are vulnerable to damage by repetitive stimulation. Repeated daily restraint stress for 21 days caused apical dendrites of CA3 pyramidal neurons to atrophy, while basal CA3 dendrites did not change. Rats undergoing this treatment were healthy and showed some adaptation of the glucocorticoid stress response over 21 days; however, stress reduced body weight gain by 14% and increased adrenal weight relative to body weight by 20%. Results are discussed in relation to the possible role of adrenal steroids and excitatory amino acids.

Animals↗

PubMed1992

L-threo-3,4-dihydroxyphenylserine enhanced ocular dominance plasticity in adult cats.

We studied whether ocular dominance plasticity can be restored to the aplastic visual cortex of the adult cat by peripheral administration of L-threo-3,4-dihydroxyphenylserine (L-threo-DOPS), an exogenous precursor of L-noradrenaline (NA). We found that NA output in the visuocortical dialysate was significantly increased by a single administration of L-threo-DOPS (200 mg or 1 g, i.p.). Single unit recordings revealed a significant reduction of binocular cells (binocularity = 0.30) in juvenile cats (7-8 months of age) that had been monocularly deprived for one month in combination with L-threo-DOPS (200 mg/day, per os). These results suggest that peripheral administration of L-threo-DOPS enhances ocular dominance plasticity, presumably through activation of the central noradrenergic system.

Animals↗

PubMed1992

Platelet-derived growth factor BB-dimer suppresses the expression of macrophage colony-stimulating factor in human vascular smooth muscle cells.

Vascular smooth muscle cell is a major cell component involved in the process of atherosclerosis. In the present study, we investigated the effects of platelet-derived growth factor (PDGF)-BB dimer on the expression of macrophage-colony stimulating factor (M-CSF) in vascular smooth muscle cells isolated from human umbilical artery. On Northern blot analysis of total RNAs isolated from smooth muscle cells, with human cDNA for M-CSF, a marked dose-dependent reduction of mRNA level was found in PDGF-BB-treated smooth muscle cells. Cellular production of M-CSF was estimated by immunoblot analysis of cell lysate with specific polyclonal antibody against recombinant human M-CSF. A concentration of 10 ng/ml PDGF-BB significantly reduced M-CSF mass in smooth muscle cells compared with that in the absence of PDGF-BB. These results suggest that PDGF-BB plays an important role in the cellular metabolism of vascular wall by regulating the rate of M-CSF production in vascular smooth muscle cells.

Antibodies↗

PubMed1992

Nucleosides and nucleotides. 112. 2-(1-Hexyn-1-yl)adenosine-5'-uronamides: a new entry of selective A2 adenosine receptor agonists with potent antihypertensive activity.

Chemical modifications of the potent A2 adenosine receptor agonist 2-(1-hexyn-1-yl)adenosine (7, 2-HA) at the 5'-position have been carried out to find more potent and selective A2 agonists. These analogues were evaluated for adenosine A1 and A2 receptor binding affinity in rat brain tissues and antihypertensive effects in spontaneously hypertensive rats (SHR). Among the series of compounds, 2-(1-hexyn-1-yl)adenosine-5'-N-cyclopropyluronamide (16d) had the most potent affinity to the A2 receptor with a Ki of 2.6 nM, which is essentially the same as that of the parent agonist, 2-HA. However, the most selective agonist for the A2 receptor was 2-(1-hexyn-1-yl)adenosine-5'-N-methyluronamide (16b) with a Ki of 11 nM and a 162-fold selectivity. The N-alkyl substituents of 5'-uronamide derivatives did not seem to potentiate the A2 binding affinity but drastically reduced the A1 affinity compared with the parent 2-HA. Therefore, the A1/A2 selectivity was consequently increased. Other 5'-deoxy-5'-substituted derivatives of 2-HA such as the chloro (20), carboxamide (27, 28), sulfonamide (29), urea (30), and thiourea (22) analogues were also prepared. Among these nucleosides, no active compounds with potent or selective affinities to both receptors were found except 20. Although glycosyl conformations and sugar-puckering of these nucleosides were studied by 1H NMR spectroscopy, there were no positive correlations between active and inactive agonists. 2-(1-Hexyn-1-yl)adenosine-5'-uronamide (16a) and 16d had a potent hypotensive effect at ED30 values of 0.18 and 0.17 micrograms/kg, respectively, upon iv administration to anesthetized SHR.

Adenosine↗

PubMed1992

Selective decreased de novo synthesis of glomerular proteoglycans under the influence of reactive oxygen species.

The effect of reactive oxygen species on de novo synthesis of heparan sulfate proteoglycans (HSPGs) of the renal glomerulus was investigated in an organ perfusion system. Isolated kidneys were perfused for 7 hr with a medium containing [35S]sulfate to label sulfated proteoglycans or [35S]methionine to label total glomerular glycoproteins. For the generation of reactive oxygen species, xanthine and xanthine oxidase were included in the perfusion medium, and catalase and superoxide dismutase were used as scavenging agents. Proteoglycans were characterized by Sepharose CL-6B and DEAE-Sephacel chromatographies and SDS/PAGE analysis. The labeled glycoproteins were immunoprecipitated with anti-HSPG, anti-type IV collagen, and anti-laminin, and their specific radioactivities were determined. With exposure to reactive oxygen species, a drastic dose-dependent decrease in de novo synthesis of proteoglycans was seen, and that effect was reversible by catalase treatment. No alterations in the biochemical characteristics of proteoglycans were noted. Immunoprecipitation studies revealed a 16-fold decrease in the synthesis of nascent core peptide of HSPGs, while at comparable concentrations of xanthine and xanthine oxidase, synthesis of type IV collagen and laminin slightly decreased (approximately 15%). Morphologic studies revealed a 14-fold decrease in [35S]sulfate-associated autoradiographic grains overlying the glomerular basement membrane, a critical component of the ultrafiltration apparatus. Relevance of the selective decreased de novo synthesis of HSPGs of the glomerular basement membrane is discussed in terms of increased glomerular permeability to plasma proteins.

Animals↗

PubMed1992

Specific binding of CAP-50 to calcyclin.

CAP-50, a calcyclin-associated protein with an apparent molecular mass of 50 kDa, was purified and proved to be a novel annexin [Tokumitsu, H. et al. (1992) J. Biol. Chem. 267, 8919-8924]. We examined the binding of CAP-50 to other Ca(2+)-binding proteins which have two of four EF-hand structures, by a co-precipitation assay with phospholipid (phosphatidylserine). Among nine Ca(2+)-binding proteins (calcyclin, S-100 proteins, p11, calgizzarin, calvasculin, calmodulin and troponin C) examined, only calcyclin interacted with CAP-50. These results clearly show that the interaction of CAP-50 to calcyclin is specific, i.e. other Ca(2+)-binding proteins with the EF-hand structure could not substitute for calcyclin, thereby suggesting the possible role in specific regulation of the function of CAP-50 by Ca2+/calcyclin.

Animals↗