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Biomedical subjects

S Hirose

Publications and source records attributed to S Hirose.

At least 775 records · Page 43Linked to original sources
PubMed1983

Initiation site of deoxyribonucleotide polymerization at the replication origin of the Escherichia coli chromosome.

A new round of chromosomal replication of a temperature-sensitive initiation mutant (dnaC) of Escherichia coli was initiated synchronously by a temperature shift from a nonpermissive to a permissive condition in the presence of arabinosyl cytosine. Increased amounts of nascent DNA fragments with homology for the chromosomal segment containing the replication origin (oriC) were found. The nascent DNA fragments were purified and treated with alkali to hydrolyze putative primer RNA and to expose 5'-hydroxyl DNA ends at the RNA-DNA junctions. The ends were then labeled selectively with T4 polynucleotide kinase and [gamma-32P]ATP at 0 degrees C and the terminally-labeled initiation fragments were purified by hybridization with origin probe DNAs containing one each of the constituent strands of oriC-DNA segment. The 32P-labeled initiation sites were then located at the resolution of single nucleotides in the nucleotide sequence of the oriC segment after cleavage with restriction enzymes. Two initiation sites of DNA synthesis, 37 nucleotides apart, were detected in one of the component strands of the oriC; in other words, in the strand whose 5' to 3' polynucleotide polarity lies counterclockwise on the E. coli genetic map. The results support the involvement of the primer RNA in the initiation of DNA synthesis at the origin of the E. coli genome and suggest that the first initiation event is asymmetric.

Base Sequence↗
PubMed1983

Genetic regulation of the class conversion of dsDNA-specific antibodies in (NZB X NZW)F1 hybrid.

To investigate the possible effects of NZW genes on the class conversion of dsDNA-specific antibodies in NZB X NZW (B/W)F1 hybrids, we measured IgM, IgG1, and IgG2 dsDNA-specific antibodies, using the Crithidia luciliae kinetoplast immunofluorescence test, in NZB, NZW, B/W F1 hybrid, B/W F1 X NZB backcross, and B/W F1 X NZW backcross mice at 4, 7, and 10 months of age. The highest serum levels of IgM dsDNA-specific antibodies were observed in NZB mice at the ages tested; however, the amounts of IgG1 and IgG2 antibodies were scanty. In contrast, a large amount of both IgG1 and IgG2 dsDNA-specific antibodies was produced in B/W F1 hybrids, in which the serum IgM antibodies were lower than those observed in NZB mice. NZW mice were virtually negative for these antibodies. Progeny testing suggested that a combined effect of two unlinked dominant genes of the NZB strain determines the production of dsDNA-specific antibodies and that these genes only act to produce IgM antibodies. These traits are to a great degree modified by the NZW loci in B/W F1 hybrids, and a combined effect of two unlinked dominant genes leads to conversion of the class of the antibodies from IgM to IgG, which, in turn, increases the serum levels of dsDNA-specific antibodies. The F1 hybrid of C57BL/6 and NZW strains produced no dsDNA-specific antibodies, indicating that the relevant NZB predisposing genes are required for the NZW gene action. Linkage studies showed that one of such NZW genes is to some extent linked to the H-2 complex on chromosome 17, but not to Mup-1 (chromosome 4) or a coat color locus (chromosome 2). The appearance of IgG dsDNA-specific antibodies correlated well with the incidence of renal disease in B/W F1 X NZB backcross mice.

Animals↗
PubMed1983

Genetic regulation of erythrocyte autoantibody production in New Zealand black mice.

The incidences of positive anti-erythrocyte autoantibodies (AEA) in New Zealand Black (NZB), C57BL/6, their F1, F2 hybrid, and the F1 X NZB backcross mice were 100, 0, 0, 17, and 51%, respectively. This finding is in keeping with the idea that a combined effect of one to three dominant predisposing NZB gene(s) and a single dominant modifying C57BL/6 gene regulates the AEA production. Studies suggested that the modifying locus Aem-1 is loosely linked to Mup-1 locus on chromosome 4, and the gene order is Aem-1: Mup-1: Gpd-1. We analyzed the effects of the Aem-1 locus on other autoimmune traits and found that the gene action of Aem-1 is unrelated to the spontaneous productions of dsDNA-specific antibodies, the retroviral gp70-anti-gp70 immune complexes and natural thymocytotoxic autoantibodies and to the serum level of retroviral gp70. A significant association was observed between the negative AEA and the low (normal) serum IgM level in (C57BL/6 X NZB)F1 X NZB backcross mice. It remains to be determined whether the Aem-1 locus also controls the serum IgM level.

Animals↗
PubMed1983

Cloning and sequence analysis of cDNA for human renin precursor.

The primary structure of human renin precursor has been deduced from its cDNA sequence. A library of cDNA clones was constructed from human kidney poly(A)+ RNA by applying the vector/primer method of Okayama and Berg. The library was screened for human renin sequences by hybridization with the previously cloned mouse renin cDNA. Of the 240,000 colonies screened, 35 colonies that were positive for hybridization were isolated. Two recombinant plasmids containing long inserts of about 1,300 and 1,600 base pairs were selected for sequence analysis. The amino acid sequence predicted from the cDNA sequence shows that the human renin precursor consists of 406 amino acids with a pre and a pro segment carrying 20 and 46 amino acids, respectively. A high degree of sequence homology was found upon comparison of the mouse and human renins. Close similarities were also observed in the primary structures of renin and aspartyl proteinases that have known three-dimensional structures, suggesting a similar tertiary structure for renin.

Amino Acid Sequence↗
PubMed1983

Studies on salivary gland ribonucleases. III. Purification and properties of three ribonucleases from bovine parotid gland.

Three alkaline ribonucleases [EC 3.1.4.22] were purified 4,500- to 7,850-fold from bovine parotid gland by repeated CM-Sephadex C-25 chromatography and Sephadex G-50 gel filtration, with a total recovery of about 33%. They were designated as RNase BP1, BP2, and BP3, based on their order of elution from a CM-Sephadex C-25 column. The molecular weights of these enzymes were estimated by gel electrophoresis to be 18,500, 18,000, and 14,000, respectively. These enzymes are very similar to RNase A in that they are inhibited by heparin, show preferential hydrolysis of C5'-O-P linkages adjacent to a cytosine nucleotide rather than a uracil nucleotide, and in their antigenic properties. Spermine was found to stimulate the activities of these enzymes; the degree of stimulation was in the order of RNase BP3 greater than BP2 greater than BP1. The stimulation by spermine is mainly due to the increased cleavage of C5'-O-P linkages adjacent to cytosine nucleotides. From the results of amino acid analysis, glycosidase digestion and amino-terminal sequencing, it was suggested that the differences in molecular weights of RNase BP1, BP2, and BP3 are due to the differences in carbohydrate contents. In addition, it was suggested that RNase BP3 is identical with RNase A.

Animals↗
PubMed1983

Purification and properties of an endoribonuclease existing as a complex with inhibitor in rat liver cytosol.

An endoribonuclease existing as a complex with inhibitor in the cytosol of rat liver has been purified about 128,000-fold after inactivation of the inhibitor with CdCl2. The enzyme had a molecular weight of 16,000 and produced 3'-CMP via 2',3'-cyclic phosphate of cytidine from poly(C). The breakdown of poly(U) by the enzyme was less than 5% of poly(C) breakdown. Poly(A) was not hydrolyzed by the enzyme. The enzyme had a pH optimum of 7.5-8, was heat-stable and had a Km of 952 micrograms yeast RNA and a Km of 198 micrograms poly(C) per ml. The maximal velocities for yeast RNA and poly(C) degradation were 3,970 A260/min/mg protein and 1,890 A260/min/mg protein, respectively. The enzyme was slightly stimulated by polyamines or monovalent and divalent cations except Mn2+, but was inhibited by nucleoside triphosphate, poly(G) and rat liver RNase inhibitor. Inhibition of the enzyme by rat liver RNase inhibitor was not prevented by monovalent and divalent cations or polyamines, although inhibition by poly(G) was prevented by these ions.

Ammonium Sulfate↗
PubMed1983

The relationship between mental disorders and physical severities in patients with acute myocardial infarction.

We studied the relationship between the mental disorders and the mental severities of 163 patients with acute myocardial infarction (AMI), who were admitted to the CCU (Coronary Care Unit) of Nippon Medical School Hospital during the past 2 years. Their mental disorders were diagnosed by psychiatrists, and the relationship between their physical severities according to Killip's classification and their mental severities was investigated. Based on these studies, the authors described the way to manage AMI patients in a CCU, especially from a psychiatric point of view. 1) About 64% of all the patients showed some mental disorders, and many of them were in a state of anxiety or depression. In most of the cases their mental severities were considered to be mild or moderate. 2) We found some correlation between physical severities according to Killip's classification and mental severities (r = 0.3061, p less than 0.005). Many patients with grade I of Killip's classification showed a normal or mild severity, and many with grade II had a mild or moderate severity. About one half of the patients with grades III and IV showed moderate and severe severities, respectively. 3) About 26% of the subjects were in need of psychotropic medication. 4) About 10% of the subjects showed disorientation or cloudy consciousness. The mental severity of patients with an acute lidocaine intoxication was severe. These results showed that there was a significant correlation between physical severity according to Killip's classification and mental severity of AMI patients in the CCU. Patients whose physical severity was not so great showed comparatively mild mental disorders. As Killip's grade of physical severity progressed, mental disorder became more severe.

Adult↗
PubMed1983

Cell-free translation of human renin mRNA.

The molecular weight of human renin precursor (preprorenin) was determined to be 43,000 by cell-free translation of its mRNA. Poly(A)+-containing RNA from human infarcted kidney was translated in a cell-free reticulocyte lysate system containing [35S] methionine. Immunoprecipitation with anti-renin antibody gave one major band with an apparent Mr = 43,000, as determined by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis and fluorography. The specific band, which represents the prepro-form of human renal renin, was very similar to mouse submandibular gland preprorenin in its electrophoretic mobility.

Animals↗
PubMed1983

Alveolar soft-part sarcoma. A review on its histogenesis and further studies based on electron microscopy, immunohistochemistry, and biochemistry.

To date, the histogenesis of alveolar soft part sarcoma has been considered to be of paraganglioma origin, striated muscle cell origin, or as a malignant granular cell myoblastoma, neural neoplasm, or renin-producing tumor. Further studies for these existing theories were performed based on various methods. The negative formaldehyde-induced fluorescence and the immunohistochemical absence of neuron-specific enolase were against the paraganglioma theory. The immunohistochemical absence of myelin proteins (P2 protein and PO protein) and S-100 protein were against the malignant granular cell myoblastoma and neural neoplasm theory. Furthermore, there was a totally negative immunohistochemical finding for renin in the tumor cells, and the biochemical relationship of the tumor and renin was completely negated. The contradiction in a well-known report that the components of crystals were considered to be Z-band materials such as tropomyosin was referred to based on recent myological data. Concurrently, the absence of tropomyosin was immunohistochemically demonstrated. Hence, the issues on the histogenesis of alveolar soft part sarcoma and the identity of the characteristic crystalloids remain open for discussion.

Adult↗
PubMed1983

Genetic studies of autoimmunity in New Zealand mice. IV. Contribution of NZB and NZW genes to the spontaneous occurrence of retroviral gp70 immune complexes in (NZB X NZW)F1 hybrid and the correlation to renal disease.

We designed a polyethylene glycol precipitation method for detecting retroviral gp70-anti-gp70 immune complexes (gp70 IC) in the circulation of mice. To determine the genetic contribution of NZB and NZW strains to the spontaneous occurrence of circulating gp70 IC in NZB X NZW (B/W)F1 hybrids, we measured these IC in female NZB, NZW, (NZB X NZW)F1 (B/W F1), B/W F1 X NZW backcross, and B/W F1 X NZB backcross mice. The highest amounts of gp70 IC were found in B/W F1 and the lowest in NZW mice, and the order of the average serum levels was B/W F1, B/W F1 X NZB, B/W F1 X NZW, NZB, and NZW. Genetic analyses suggested that two major dominant genes, one from NZB and the other from NZW, are involved in the formation of these gp70 IC. A single dominant gene of NZB strain determines the formation of these IC, and the magnitude is to a great degree modified (intensified) by the NZW gene. In addition, statistical analyses of data obtained in the studies of B/W F1 X NZW backcrosses suggested the presence of one additional dominant NZB gene that also regulates the magnitude of gp70 IC formation in concert with the other NZB gene. Since all these New Zealand mice share a high serum level of free gp70, the formation of gp70 IC represents the gene action on the production of anti-gp70 antibodies. Linkage studies showed that both of the major NZB and NZW genes are loosely linked to the H-2 complex but not to either the Mup-1 or coat color gene loci examined. The incidence of proteinuria correlated well with the serum level of gp70 IC in both B/W F1 X NZW and B/W F1 X NZB backcross mice.

Aging↗
PubMed1983

[Renal function after anesthesia and abnormal surgery. A comparative study between halothane and epidural anesthesia].

Beta 2-microglobulin (BMG) and osmolarity (OSM) in the plasma and in the urine were measured in 23 adult female patients before and after abdominal surgery. Creatinine clearance (Ccr) and free water clearance (C-H2O) were determined simultaneously. These patients were divided into two groups, the first group receiving halothane anesthesia (n = 14) and the second group undergoing epidural anesthesia (n = 9). Results were summarised as follows. Ccr temporarily increased in both groups on the day of operation (0-POD) and on the 1st postoperative day (1-POD), suggesting a physiological compensation to the increased metabolic and circulatory needs in the post-operative state. Urinary BMG (U-BMG) concentration remarkably increased in both groups after the operation but the plasma BMG levels were unchanged. U-BMG returned to the pre-operative levels on the 4-POD in the 1st group and on the 2-POD in the 2nd group. Tubular dysfunction after anesthesia and surgery is believed to be responsible for this marked rise in U-BMG. The earlier recovery of U-BMG to the preoperative levels in the 2nd group indicates that the tubular dysfunction in epidural anesthesia is probably less in halothane anesthesia. The results of C-H2O and urine OSM studies also indicate the postoperative tubular dysfunction but these parameters may not be so sensitive as U-BMG.

Abdomen↗