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Y Tsutsui

Publications and source records attributed to Y Tsutsui.

At least 91 records · Page 5Linked to original sources
PubMed1987

[A case of Bartter-like syndrome with abdominal pain, paresis of the extremities and muscle weakness].

A 16-year-old woman was admitted to our hospital because of abdominal pain, paresis of extremities, and muscle weakness. Bartter's syndrome was suspected because of the features of the hypokalemia, hyperaldosteronism, hyperreninemia, increased concentration of plasma angiotensin I & II, the defect in distal fractional reabsorption of chloride and normotension. The concentrations of the plasma angiotensin II and aldosterone, however, were decreased to normal levels after admission probably due to a decrease in the salt intake because of the regular hospital diet. Furthermore, the hyperplasia of the juxtaglomerular apparatus was not found. Therefore, at first we thought we were dealing with another disease, that is pseudo-Bartter's syndrome, which is caused by different pathogenesis. Gill et al. reported that the defect in distal fractional reabsorption of chloride was a characteristic feature in the diagnosis of the Bartter's syndrome. Thus, we tried to explain the clinical symptoms and diagnosis of this case as the Bartter's syndrome according to the theory of Gill et al. If the defect of chloride reabsorption was the only pathogenesis of the Bartter's syndrome, other symptoms seen in our case could be thought of as secondary (or new) changes. Therefore, this case could be differentiated from the pseudo-Bartter's syndrome or the "true" Bartter's syndrome because of the clinical symptoms and the defect in chloride reabsorption.

Abdomen↗
PubMed1987

Viral replication in HeLa/fibroblast hybrid cells infected with human cytomegalovirus.

Three human hybrid cell lines were generated by the fusion of D 98OR, a HeLa cell variant, and TIG human diploid fibroblasts. Chromosome numbers of the hybrid cells fell between that of D 98OR cells and the combined chromosome number of the two cell lines, with three marker chromosomes identical to those of D 98OR cells. One hybrid, B-3, produced large amounts of human fibronectin as analyzed by immunohistochemistry. Only human cytomegalovirus (HCMV) infected B-3 cells showed positive fluorescence as detected by human antiserum to HCMV. Further cloning of B-3 by limiting dilution resulted in two cloned hybrids with markedly enhanced virus production as compared with B-3 cells. Treatment of these two clones with phorbol ester further enhanced virus production. These cloned hybrids may provide a tool to analyze host cell factors controlling the transcription and replication of HCMV.

Antigens, Viral↗
PubMed1987

Induction of S-100b (beta beta) protein in human teratocarcinoma cells.

Human teratocarcinoma NT2/D1 cells undergo differentiation into a variety of cell types, including neurons, treated with retinoic acid. In the present study, the concentrations of alpha S-100 and beta S-100 proteins (alpha and beta subunits of S-100 proteins), and three subunits (alpha, beta and gamma) of enolase in NT2/D1 cells were measured using the sensitive enzyme immunoassay method. The concentration of beta S-100 was markedly increased in the cells after treatment with retinoic acid, whereas the concentration of alpha S-100 was undetectably low, indicating that the S-100b (beta beta) protein was induced by retinoic acid. On the other hand, the concentrations of the three forms of enolase isozymes did not change in the same culture. The induction of S-100b protein was not observed in the NT2/D1 cells after treatment with forskolin, dibutyryl cyclic AMP or cholera toxin. The indirect double-labeled immunofluorescence, using antibodies specific to beta S-100 and monoclonal antibodies specific to neurofilaments, revealed that both the S-100b protein and the neurofilaments were induced in the same subpopulation of cells which underwent neuronal differentiation.

Antibodies, Monoclonal↗
PubMed1987

Murine cytomegalovirus infection of cultured mouse embryos.

Isolated mouse whole embryos of 7.5 days' gestation were infected with murine cytomegalovirus (MCMV) and cultured in pure rat serum. Although the MCMV infection had little effect on the survival and development of the embryos during 3 days of cultivation, immunohistochemical analysis of their serial sections using monoclonal antibody showed MCMV-infected cells in various portions of the embryos. This monoclonal antibody, when tested with the use of infected cultured mouse fibroblasts, reacted with nuclear antigen within 2 hours after infection and also reacted with nuclear inclusions in the late phase of infection. The viral antigen-positive cells detected by the monoclonal antibody were present in almost all of the ectoplacental cone and the yolk sac and in about 82% of the embryos. In the embryos, antigen-positive cells were frequently observed in the epithelium of the digestive tracts, endothelial cells of the blood vessels, and the mesodermal cells. In some of the embryos, viral antigen-positive cells were clearly observed in a small percentage of the blood cells. These findings indicate that blood cells, in addition to cell migration during embryogenesis, may play an important role in transmission of infectious virus into the embryos. Mouse whole embryo culture infected with MCMV can provide a model for the study of cellular tropism related to congenital infection by cytomegalovirus.

Animals↗
PubMed1986

Biochemical and immunological characterization of Suncus murinus mammary tumor virus DNA polymerase.

Enzymological properties of the RNA-directed DNA polymerase associated with the Suncus murinus mammary tumor virus (Sm-MTV) was investigated and its antigenic relatedness to other retroviral DNA polymerases was examined. The enzyme exhibited higher activity in the presence of Mg2+ than in the presence of Mn2+ with endogenous RNA as well as with almost all of the synthetic template X primers tested. Mg2+ was also effective with poly(2'-O-methylcytidylate) X oligodeoxyguanylate which was known to be specific for Mn2+. To examine the immunological relatedness of this enzyme with other retroviral DNA polymerases, remaining Sm-MTV DNA polymerase activity was measured after treatment of this enzyme with various antisera prepared against each of the reverse transcriptases of Mason-Pfizer monkey virus (MPMV), murine mammary tumor virus (MuMTV), simian sarcoma virus-simian sarcoma associated virus (SSV/SSAV), and Rauscher murine leukemia virus (RLV). No inhibition of the Sm-MTV enzyme activity was observed when treated with the latter three antisera with which the DNA polymerase activities of the corresponding retroviruses were fully inhibited. Only the antiserum against MPMV-enzyme, however, was found to slightly inhibit the Sm-MTV enzyme activity. These results indicate that Sm-MTV DNA polymerase has similar enzymological properties to those of MPMV and MuMTV and shares some common antigenic determinant group(s) with MPMV DNA polymerase.

Animals↗
PubMed1986

Monoclonal antibodies to guinea-pig cytomegalovirus: an immunoelectron microscopic study.

Three groups of monoclonal antibodies which reacted with cells infected by guinea-pig cytomegalovirus (GPCMV) were prepared. The first group of antibodies immunoprecipitated a 50 000 mol. wt. (50K) polypeptide of GPCMV-infected cells. This polypeptide was identified as part of the nuclear inclusion by immunofluorescence. This nuclear fluorescence was markedly diminished when the infected cells were incubated in the presence of phosphonoacetic acid. By immunoelectron microscopy the antibodies reacted mainly with filamentous structures (26 to 28 nm in diameter) in nuclear inclusions and occasionally stained nucleocapsids. Neither intracytoplasmic nor extracellular virions reacted with the antibodies. Therefore, the 50K protein with which the monoclonal antibodies reacted was nuclear inclusion-specific and a non-structural protein. The second group of antibodies reacted with a 76K polypeptide of the infected cells which was a matrix protein found in both cytoplasmic inclusions and extracellular dense virions. The third group of antibodies mainly reacted with a virion core protein by immunoelectron microscopy.

Animals↗
PubMed1986

Ultrastructural characterization of the retrovirus particles (Sm-MTV) liberated from the mammary tumor cell line (Sm-MT) of a house musk shrew, Suncus murinus (Insectivora).

Detailed ultrastructure of a new type of retrovirus (Sm-MTV) released by cultured cells (Sm-MT) of a spontaneous mammary tumor from a house musk shrew Suncus murinus, Insectivora, is described. The virus particles were revealed as three forms: intracellular; budding; and extracellular. The intracellular type A particles were similar in profile to those associated with mouse mammary tumor cells and tended to form a small cluster of several particles in the cytoplasm. In addition, horseshoe-shaped particles as well as smaller particles in clusters, with doughnut-shaped morphology similar in structure to type A particles, were identified near the clusters of type A particles, although in smaller numbers. The budding particles contained a doughnut-shaped nucleoid, although the nucleoids decreased in size as compared with intracytoplasmic type A particles. The extracellular virions consisted of an envelope and a centrally located nucleoid. In routinely fixed specimens, the former was covered with irregularly distributed fuzzy materials in its surface, and the latter was further composed of a small electron dense core surrounded by an intermediate layer. Tannic acid treatment of cells resulted in the visualization of surface projections on the envelope of virions. Similar projections were also detected exclusively on the plasma membrane where virus budding took place, and not on the normal plasma membrane. The presence of surface projections on the viral envelope was further confirmed by the whole-cell-mounting technique. Together with our previous results of biochemical and immunological investigations, we concluded that Sm-MTV seemed to have closer phylogenetic relatedness with type D viruses of primates than with murine mammary tumor virus.

Animals↗
PubMed1985

A new retrovirus produced by tissue culture cell line from mammary tumor of a house musk shrew, Suncus murinus.

A new type of retrovirus (Sm-MTV) released by cultured cells of a spontaneous mammary tumor from a house musk shrew, Suncus murinus, is described. The Sm-MTV is distinct morphologically from type C particles. In spite of certain morphological similarities to type B and type D retroviruses, the Sm-MTV is readily distinguishable. The extracellular virions had a spikeless envelope containing a centrally located nucleoid with a small electron-dense core surrounded by an inner membrane. The budding particles contained a doughnut-shaped nucleoid. Intracytoplasmic type A particles similar in profile to those associated with mouse mammary tumor cells were also found, and tended to form a small cluster of several particles in the cytoplasm. The virus banded at 1.169 g/cm3 in isopycnic centrifugation and possessed constitutive Mg2+-dependent reverse transcriptase. The viral RNA had a molecular size ranging from 50 to 70 S in its native form and 30 to 40 S in its denatured form by a glycerol gradient ultracentrifugation. Major viral polypeptides were 72K, 69K, 47K, 44K/43K, 27K, 20.5K, and 15K.

Animals↗
PubMed1984

Monoclonal antibodies to the nuclear matrix of chick embryonal erythrocytes.

Monoclonal antibodies were prepared from mice that had been immunized with the nuclear matrix from chick embryonal erythrocytes. Seven stable clones were obtained by an ELISA that used nuclear lysate as the solid phase. Six clones of them reacted with the nuclear matrix, and one reacted with nuclear components other than the matrix. Immunoblotting showed that one clone recognized the 72K polypeptide, two clones recognized the 69K polypeptide and three clones recognized both the 69K and 44K polypeptides. Indirect immunofluorescence that used antibodies to the nuclear matrix showed homogeneous nuclear fluorescence in cultured chick embryonal fibroblasts, and intense fluorescence was present in the peripheral part of the nucleus in thin-sectioned chick embryos. Only weak nuclear fluorescence was seen in fibroblasts from humans and rats when two of the antibodies which recognized only 69K polypeptide were used. The rest of the antibodies to the nuclear matrix produced no nuclear fluorescence in human and rat fibroblasts. The metaphase-rich population of chick embryonal fibroblasts were stained diffusely over the entire cytoplasm, but not the chromosomes, when antibodies to the nuclear matrix were used. These results indicate that monoclonal antibodies we prepared are directed to the major proteins of the nuclear matrix that correspond to the lamin A and B defined in rat liver.

Animals↗
PubMed1984

[The analgesic and antipyretic effects of a non-steroidal anti-inflammatory drug, oxaprozin, in experimental animals].

The analgesic and antipyretic effects of oxaprozin were investigated in comparison with those of indomethacin, ibuprofen, phenylbutazone and aspirin. On the various writhing tests in mice, the analgesic effect of oxaprozin was about 2 to 9 times more potent than those of ibuprofen, phenylbutazone and aspirin. On the other hand, the analgesic and antipyretic effects of oxaprozin in rats were roughly equivalent to those of aspirin, but less effective than those of the other drugs tested. On the urate synovitis test in dogs, only oxaprozin showed a prophylactic effect. Therefore, The effect of oxaprozin in mice and dogs was more potent than ibuprofen, phenylbutazone and aspirin. The metabolic rate of oxaprozin in rats is 3.5 and 7.2 times more rapid than in mice and dogs, respectively, and its blood level in rats is low. Moreover, the biological half-life of oxaprozin is 39 to 43 hr and 49 to 69 hr in dogs and humans, respectively. From these results, it is suggested that oxaprozin is more potent than ibuprofen, phenylbutazone and aspirin, and in clinical use, it is a long acting anti-inflammatory drug.

Analgesics↗
PubMed1983

Heat(40 degrees C)-induced polypeptides in human embryonic fibroblasts.

The synthesis of 3 polypeptides with molecular weights of 103-, 80- and 78-kdalton (K) was dramatically accelerated when the cultures of human embryonic fibroblasts were transferred from 37 to 40 degrees C. The induction of these polypeptides was not observed if actinomycin D was added to the cultures at the beginning of the rising of the temperature, indicating that this response may be mediated by increased transcription of their messenger RNA.

Female↗
PubMed1983

Role of the nuclear matrix in the growth of herpes simplex virus type 2.

Nuclear matrix was prepared from Vero cells infected with herpes simplex virus type 2. In the early stage of infection, both 155K and 110K viral proteins were associated with the nuclear matrix, while in the late stage, 155K protein, presumably a viral capsid protein, was predominantly associated with the matrix. Electron microscopic study showed that empty capsids were bound to the filamentous networks of the nuclear matrix of the late stage. Neither viral DNA nor viral DNA polymerase activity was associated with the nuclear matrix. These results may indicate that the nuclear matrix plays some role in the growth of herpes simplex virus, especially during the morphogenesis.

Animals↗
PubMed1983

Quantitative analysis of mouse mammary tumor virus in milk in two sublines of RIII/AnOk mice with low and high mammary tumor incidence.

Mammary tumors have ceased to develop in descendants of one female of the RIII/AnOk mouse strain which was brought from the Mouse Colony of Okayama University Medical School in 1975, while descendants of another female of this strain have maintained a high tumor incidence. The former and latter descendants were separated out as RIII/AnOk/2 and RIII/AnOk/1 sublines, respectively. The amount of mouse mammary tumor virus (MMTV) in the milk of individual females in these two sublines was determined by means of a sensitive enzyme immunoassay. No MMTV antigens were detected in 59 milk samples of RIII/AnOk/2 females collected during the 1st to 7th lactation periods. On the other hand, all the milk samples of RIII/AnOk/1 females contained MMTV antigens with concentrations ranging from 9 to 400 micrograms/ml. When RIII/AnOk/2 mice were foster-nursed by RIII/AnOk/1 mothers, the infected RIII/AnOk/2 females produced MMTV in the milk to almost the same degree as did the RIII/AnOk/1 females. No genetic differences between the two sublines were observed by the use of reciprocal skin grafting, tumor transplantation, and analysis of biochemical genetic markers. These results indicate that the arrest of mammary tumor development in the RIII/AnOk/2 subline was due to the disappearance of MMTV in the milk.

Animals↗
PubMed1982

Effects of DNA polymerase inhibitors on replicative and repair DNA synthesis in ultraviolet-irradiated HeLa cells.

Aphidicolin specifically inhibits eukaryotic DNA polymerase alpha, while 2',3'-dideoxythymidine 5'-triphosphate (d2TTP) inhibits DNA polymerase beta and gamma but not alpha. 1-beta-D-Arabinofuranosylcytosine 5'-triphosphate (araCTP) inhibits both DNA polymerase alpha and beta although to a different extent. Here we measured the effects of these inhibitors on repair DNA synthesis of U.V.-irradiated HeLa cells by two different methods. Firstly, aphidicolin, 1-beta-D-arabinofuranosylcytosine (araC, a precursor of araCTP) and 2',3'-dideoxythimidine (d2Thd, a precursor of d2TTP) were added directly to the culture medium. In this case, aphidicolin and araC strongly inhibited replicative DNA synthesis of HeLa cells, and they also inhibited repair synthesis after U.V.-irradiation but to a much lesser extent. In contrast, high concentrations of d2Thd inhibited repair DNA synthesis to a higher extent than replicative DNA synthesis. Secondly, the active form of inhibitor, d2TTP, was microinjection directly into cytoplasm or nuclei or U.V.-irradiated HeLa cells. Microinjection of d2TTP effectively inhibited repair synthesis. The microinjection of d2TTP, into either cytoplasm or nucleus, strongly inhibited replicative synthesis. These results might indicate that multiple DNA polymerases are involved in repair synthesis as well as in replicative synthesis.

Aphidicolin↗
PubMed1982

Gene transfer: DNA microinjection compared with DNA transfection with a very high efficiency.

We have developed a procedure that gives a very high efficiency of transfection in mammalian cells with low-molecular-weight DNA (approximately 10(4) base pairs). The procedure uses cells in suspension that are shocked with polyethylene glycol 4 h after replating. We compared this transfection technique to the standard technique involving manual microinjection of DNA into the nuclei of mammalian cells, using recombinant plasmids containing the simian virus 40 A gene or the herpes simplex virus thymidine kinase gene or both. The efficiency of transfection depends on a number of variables, the most important of which is the difference in transfectability of different cell lines. In our laboratory, the cell line that had the highest efficiency of transfection was tk-ts13, which is derived from baby hamster kidney cells that are deficient in thymidine kinase and temperature sensitive for growth. Under the appropriate conditions, as many as 70% of these cells can be transfected so that transient gene expression can be detected. With the manual microinjection technique, gene expression is independent of the cell line used and occurs faster than after transfection. The results suggest that the critical stage in transfection is the delivery of DNA molecules to the nucleus. Our experiments also indicate that an enzymatic function, in our case, thymidine kinase activity, gives a higher percentage of positive transfectants than when proteins are visualized only by indirect immunofluorescence. The transfection procedure described in this paper is simple and reproducible and, although less efficient than microinjection, ought to be useful in phenotypic and genotypic studies in which transfer of genes to a large number of cells is desirable.

Animals↗