Biomedical subjects

K Hamana

Publications and source records attributed to K Hamana.

At least 37 records · Page 2Linked to original sources

PubMed1994

Postthaw viability of the inner cell mass of in vitro-matured/in vitro-fertilized bovine embryos frozen in various cryoprotectants.

A study was conducted to examine the viability of inner cell mass (ICM) cells of frozen-thawed in vitro-matured (IVM)/in vitro-fertilized (IVF)-derived embryos using various cryoprotectants. Expanded blastocysts were frozen and thawed in 1.4 M glycerol with 0.25 M sucrose (GL), 1.6 M propylene glycol (PG), 1.8 M ethylene glycol (EG), or 1.3 M ethylene glycol monomethyl ether (EME) as cryoprotectants using a one-step method. After thawing, the embryos were cocultured for 24 h with cumulus cells in TCM199. Embryos which were viable after thawing and developed beyond the blastocyst stage were treated by immunosurgery and differential fluorochrome staining for ICM cell counts. Overall, there were no significant differences in the development to blastocyst stage after 24 h culture in each cryoprotectant (P < 0.05, chi 2 analysis). The viability of ICM cells of frozen-thawed embryos with each cryoprotectant was lower (GL, 72.7%; PG, 67.8%; EG, 77.5%; EME, 74.7%) than that of unfrozen embryos (84.4%). In the case of PG as a cryoprotectant, viability of ICM cells was significantly lower than that of unfrozen embryos (P < 0.05, ANOVA analysis). Our results suggest that the viability of ICM cells of frozen-thawed bovine embryos tend to be lower than that of unfrozen embryos irrespective of the cryoprotectants used. PG was significantly more toxic to the ICM cells compared with the other cryoprotectants.

Animals↗

PubMed1994

Occurrence of tertiary and quaternary branched polyamines in thermophilic archaebacteria.

Polyamines of thermophilic archaebacteria were analysed by high-performance liquid chromatography and gas chromatography. Thermoplasma acidophilum and Thermoplasma volcanium ubiquitously contained spermidine and spermine. Four species of Sulfolobus, S. acidocaldarius, S. solfataricus, S. metallicus and S. shibatae, two species of Acidianus, A. brierleyi and A. infernus, and Metallosphaera sedula, contained norspermidine and norspermine in addition to spermidine and spermine, but quantitative distribution profiles were species-specific. A tertiary tetra-amine, N4-aminopropylspermidine, and a quaternary penta-amine, N4-bis(aminopropyl)spermidine, were detected as a major polyamine in three species of Thermococcus, T. celer, T. litoralis and T. stetteri, and two Pyrococcus species, P. furiosus and P. woesei. This is the first report on the occurrence of branched polyamines in archaebacteria.

Archaea↗

PubMed1993

A Globosus amorphus from an in vitro fertilized embryo transferred to a Japanese black cow.

A Globosus amorphus along with a living calf was encountered following the transfer of blastocysts obtained by in vitro fertilization of in vitro-matured follicular oocytes in Japanese black cattle. Two embryos obtained 9 days after in vitro fertilization developed into either a hatched blastocyst with distinct inner cell mass or an expanded blastocyst with indistinct inner cell mass. The embryos were loaded into a 0.25-ml plastic straw and were nonsurgically transferred to the uterus of a heifer on Day 8 (Day 0 = estrus). On Day 75, a twin pregnancy was ultrasonically diagnosed in the right uterine horn, in which a live fetus with distinct limbs and a concomitant ovoid mass were detected. On Day 287, the dam developed parturient paralysis with dropsy of the fetal membranes. By palpation per rectum an ovoid mass was detected in the body of the uterus [corpus uteri] and a larger live fetus was in the uterine horn. A cesarean section was performed to extract a live fetus and a Globosus amorphus. The live fetus was female with the 60, XX female complements.

Journal Article↗

PubMed1993

Monitoring bovine embryo viability with early pregnancy factor.

The viability of the bovine embryo was monitored by measuring the early pregnancy factor (EPF). The EPF activity was measured by the rosette inhibition test before and after artificial insemination (AI) at natural estrus (n = 14), and after superovulatory treatment followed by embryo removal on day 7 after AI (n = 5). In the cows inseminated artificially at natural estrus, there were significant differences (p < 0.01) in the rosette inhibition titer (RIT) between pregnant and non-pregnant cows on day 13-16 and day 20-25 after AI. In the 8 pregnant cows, the RIT remained more than 5 from day 6-9 after AI. In the 6 non-pregnant cows, two patterns were observed. In one pattern, RIT rose transiently to more than 5 and decreased to less than 4 thereafter. In the other pattern, RIT remained less than 4 throughout the experimental period. The former pattern suggested early embryonic death, while the latter suggested that fertilization had not taken place or that early embryonic death had occurred before the first blood collection on day 6-9 after AI. In the cows superovulated followed by embryo removal on day 7 after AI, the RIT values were all less than 4 on the day of AI (day 0), rose to more than 5 on day 3 and thereafter then until the day of embryo removal on day 7. In 4 cows, the RIT decreased to less than 4 by 3 days after embryo removal, and in the remaining one cow, the RIT decreased to less than 4 by 7 days after embryo removal. These findings suggest that the measurement of EPF activity is useful for monitoring the viability of bovine embryos.

Animals↗

PubMed1993

Tertiary and quaternary branched polyamines distributed in thermophilic Saccharococcus and Bacillus.

The distribution of long linear, tertiary and quaternary branched polyamines in twenty thermophilic Gram-positive strains belonging to the genera Saccharococcus, Bacillus or Amphibacillus were analysed by high-performance liquid chromatography and gas chromatography. The extremely thermophilic S. thermophilus contained a tertiary tetra-amine, N4-aminopropylspermidine, a linear penta-amine, thermopentamine, a tertiary penta-amine, N4-aminopropylspermine, and a quaternary penta-amine, N4-bis(amino-propyl)spermidine. N4-aminopropylspermine [NH2(CH2)3N((CH2)3NH2)(CH2)4NH(CH2)3NH2] first found in this study, was also detected in the extremely thermophilic 'B. caldolyticus' and 'B. caldotenax' and the moderately thermophilic B. stearothermophilus, B. smithii and B. thermocatenulatus.

Bacillus↗

PubMed1992

Novel linear and branched polyamines in the extremely thermophilic eubacteria Thermoleophilum, Bacillus and Hydrogenobacter.

Novel tertiary branched tetra-amines, quaternary branched penta-amines, linear penta-amines and linear hexa-amines were distributed as the major polyamines in six obligately extremely thermophilic eubacteria belonging to Thermoleophilum, Bacillus or Hydrogenobacter. The major polyamine of Thermoleophilum album and Thermoleophilum minutum was identified as a quaternary branched penta-amine, 4,4-bis(3-aminopropyl)-1,8-diamino-4-azaoctane (NH2[CH2]3N+([CH2]3NH2)2[CH2]4NH2) by h.p.l.c., t.l.c. and g.c.-m.s. Hydrogenobacter thermophilus and Hydrogenobacter halophilus contained another quaternary branched penta-amine, 4,4-bis(3-aminopropyl)-1,7-diamino-4-azaheptane (NH2[CH2]3N([CH2]3NH2)2[CH2]3NH2) as the major polyamine, and tertiary branched tetra-amines (4-(3-aminopropyl)-1,7-diamino-4-azaheptane (NH2[CH2]3N([CH2]3NH2)[CH2]3NH2), 4-(3-aminopropyl)-1,8-diamino-4-azaoctane (NH2[CH2]3N([CH2]3NH2)[CH2]4NH2)) and 4,4-bis(3-aminopropyl)-1,8-diamino-4-azaoctane were confirmed as minor components. Bacillus schlegelii contained a branched tetra-amine, 4-(3-aminopropyl)-1,8-diamino-4-azaoctane, a branched penta-amine, 4,4-bis(3-aminopropyl)-1,8-diamino-4-azaoctane, a linear penta-amine, 1,16-diamino-4,8,13-triazahexadecane (NH2[CH2]3NH[CH2]3NH[CH2]4NH[CH2]3NH2) and linear hexa-amine(s), 1,20-diamino-4,8,12,17-tetra-azaeicosane (NH2[CH2]3NH[CH2]3NH[CH2]3NH[CH2]4NH[CH2]3NH2 ) and/or 1,20-diamino-4,8,13,17-tetra-azaeicosane (NH2[CH2]3NH[CH2]3NH[CH2]4NH[CH2]3NH[CH2]3NH2 ).

Bacillus↗

PubMed1992

Estradiol-17 beta modifies the induction of spermidine/spermine N1-acetyltransferase activity in the liver of lipopolysaccharide-treated mice.

In an attempt to elucidate the effects of estrogen on polyamine metabolism in lipopolysaccharide (LPS)-treated mice, we assayed polyamine content and the activity of spermidine/spermine N1-acetyltransferase (SAT) and ornithine decarboxylase (ODC) in some organs. LPS elevated N1-acetylspermidine levels in the liver and lung and putrescine levels in the liver, lung and spleen. LPS increased the activity of ODC at 6 h and that of SAT at 12 h in the liver. When estradiol-17 beta was simultaneously administered with LPS, the maximum increase in hepatic N1-acetylspermidine levels was found 6 h earlier than in the LPS control. Likewise, the peak of the hepatic SAT activity after LPS-treatment was observed 6 h earlier in the estradiol-17 beta-treated mice than in the LPS control. No such effect of estradiol-17 beta was found in the lung and spleen. The LPS-induced ODC activity was not affected by estradiol-17 beta in the liver, lung or spleen. Estrone and 16 beta-ethylestradiol (an anti-estrogen) were also effective in enhancing the LPS-induced elevation of N1-acetyl-spermidine and putrescine in the liver, while both diethylstilbestrol, which has a potent estrogenic activity without steroid structure and estradiol-17 alpha (a non-estrogenic isomer of estradiol-17 beta) were without effect. Tamoxifen (an estrogen receptor antagonist) did not suppress the estrogen-induced increase in hepatic N1-acetylspermidine levels.

Acetyltransferases↗

PubMed1992

A high-mobility-group protein and its cDNAs from Drosophila melanogaster.

We have identified, purified, and characterized a high-mobility-group (HMG) protein and its cDNAs from Drosophila melanogaster. This protein, HMG D, shares most of the characteristics of vertebrate HMG proteins; it is extractable from nuclei with 0.35 M NaCl, is soluble in 5% perchloric acid, is relatively small (molecular weight of 12,000), has both a high basic (24%) and high acidic (24%) amino acid content, and is a DNA-binding protein. HMG D exhibits characteristics of both the vertebrate HMG 1 and 2 class and the HMG 14 and 17 class of proteins. Its amino acid sequence is similar (36% amino acid identity) to that of HMG1, while its size and selective extraction with ethidium bromide are similar to properties of the HMG 14 and 17 class of proteins. HMG D is encoded by a single-copy gene that maps to 57F8-11 on the right arm of chromosome 2. Two transcripts are observed during embryogenesis; the protein is relatively stable throughout development. By the biochemical criteria of size, solubility, and amino acid content, HMG D appears to be the major HMG protein of D. melanogaster.

Amino Acid Sequence↗

PubMed1992

Polyamines as a chemotaxonomic marker in bacterial systematics.

Aliphatic linear polyamines, from diamines to hexaamines, tertiary branched tetraamines, and quaternary branched pentaamines are widely distributed in eubacteria, archaebacteria, and cyanobacteria. Twenty-four linear types and four branched types are acid extractable from bacterial cells and can be chromatographically analyzed and identified. The varieties of polyamines are due to the combination of amino acid decarboxylase activities to form diamines, aminopropyl- and aminobutyl-transfer activities mediated by aminopropyltransferases or Schiff-base complex formation, and hydroxylation activity. The absence or presence of spermidine, norspermidine or homospermidine and the occurrence of 2-hydroxyputrescine and diaminopropane are related to grouping into the alpha, beta, gamma, and delta subclasses within Proteobacteria. Flavobacterium complex and green bacteria contain putrescine and homospermidine. Gram-negative thermophiles contain long linear and branched polyamines; however, their distribution profiles are species specific. Gram-positive eubacteria, which comprise Bacillus cluster, anaerobes, and actinomycetes, ubiquitously contain putrescine and spermidine, while the occurrence of spermine is limited to thermophiles. Archaebacteria are separated into polyamine-absent methanogens and halophiles, homospermidine-dominant methanogens, spermidine-dominant methanogens, and spermidine- and norspermidine-containing thermophiles. Cyanobacteria comprise two types; one group contains homospermidine and the other spermidine. The polyamine distribution pattern can serve as a chemotaxonomic marker in bacterial classification and is associated with bacterial systematics on the level of order, family, or genus.

Bacteria↗

PubMed1991

Glucocorticoids suppress and oestrogens enhance the lipopolysaccharide-induced increase in putrescine and N1-acetylspermidine in mouse liver.

Previously we reported that administration of lipopolysaccharide (LPS) to mice increased the hepatic levels of putrescine (PUT) and N1-acetylspermidine (N1-acetyl-SPD). In the current study, we examined the in vivo effects of some steroid hormones on the LPS-induced increase in PUT and N1-acetyl-SPD. Corticosterone, hydrocortisone and dexamethasone suppressed the LPS-induced increase in PUT and N1-acetyl-SPD in mouse liver in a dose-dependent manner, dexamethasone being the most effective among them. On the other hand, oestrone and oestradiol-17 beta enhanced the LPS-induced increase in PUT and N1-acetyl-SPD in a dose-dependent manner. Oestradiol-17 alpha and 16 beta-ethyl-oestradiol, as an inactive oestradiol isomer and an antioestrogen, respectively, likewise enhanced the increase in PUT and N1-acetyl-SPD concentrations induced by LPS. 16 alpha-hydroxy-oestradiol (oestriol), 16 alpha-hydroxyestrone, 2-hydroxyoestradiol, 2-hydroxyoesterone, progesterone, testosterone, diethylstilboestrol and nonsteroidal antioestrogens such as tamoxifen and nafoxidine had no effect on the increase. Oestradiol-17 beta enhanced and corticosterone had little effect on the carbon tetrachloride-induced increase in PUT and N1-acetyl-SPD. These results suggest that glucocorticoids suppress the increase by preventing the immunological injury by Kupffer cells on hepatocytes and that the stimulatory effect of oestrogens may not be associated with their oestrogenic activities mediated by the oestrogen receptor system.

Animals↗

PubMed1991

Polyamine distributions in thermophilic eubacteria belonging to Thermus and Acidothermus.

Triamines such as norspermidine, spermidine, and homospermidine and tetraamines such as norspermine, spermine, thermospermine, and aminopropylhomospermidine were found to be distributed ubiquitously in the eight extremely thermophilic (growing at 70 degrees C) Thermus species tested. Three linear pentaamine (caldopentamine, homocaldopentamine, and thermopentamine), two linear hexaamines (caldohexamine and homocaldohexamine), two tertiary branched tetraamines (N4-aminopropylnorspermidine and N4-aminopropyl-spermidine), and quaternary branched pentaamines such as N4-bis(aminopropyl)norspermidine and N4-bis(aminopropyl)spermidine were detected in T. thermophilus HB8, T. filiformis Wai33 A1, T. flavus AT-62, and T. caldophilus GK24. The linear hexaamines and branched polyamines were absent in T. aquaticus YT-1, T. sp. X-1, T. sp. T2, and T. sp. T351, in which linear pentaamines were minor components. Moderately thermophilic Thermus ruber and Thermus sp. K-2 contained putrescine, spermidine, norspermidine, homospermidine, spermine, norspermine, thermospermine, and aminopropylhomospermidine. No pentaamines, hexaamines, or branched polyamines were found in these two moderately thermophilic Thermus species. On the other hand, moderately thermophilic, acidophilic Acidothermus cellulolyticus was devoid of all the polyamines.

Chromatography, High Pressure Liquid↗

PubMed1991

Polyamine distributions in the Falvobacterium-Cytophaga-Sphingobacterium complex.

Homospermidine was found as the major polyamine in one newly described species of Flavobacterium (F. indologenes), in three species of Sphingobacterium (S. mizutae, S. multivorium, and S. spiritivorum), and in 10 species of Cytophaga (C. aquatilis, C. arvensicola, C. heparina, C. hutchinsonii, C. johnsonae, "C. keratolytica," C. lytica, C. marinoflava, C. uliginosa, and "C. xantha"). These bacteria also all contain putrescine and agmatine as minor components. Flavobacterium indologenes and C. johnsonae contain an unusual diamine, 2-hydroxyputrescine, as a major polyamine. The polyamine distributions of four other species originally included in Flavobacterium (F. acidurans, "F. dormitator," "F. tirrenicum," and Halomonas halmophila), whose taxonomic positions are or were uncertain, were different from the group mentioned above. They either contain spermidine as the major polyamine or lack any polyamine. These results suggest that homospermidine can serve as a chemotaxonomic marker to delineate true members of the Flavobacterium-Cytophaga-Sphingobacterium complex.

Bacteria↗

PubMed1991

Alpha-tocopherol and superoxide dismutase suppress and diethyldithiocarbamate and phorone enhance the lipopolysaccharide-induced increase in N1-acetylspermidine concentrations in mouse liver.

Previously, we have shown the close association between hepatic concentrations of N1-acetylspermidine and the radical-producing potency of several drugs. Since vitamin E, superoxide dismutase (SOD), and reduced glutathione (GSH) are known to scavenge free radicals, in this study we tested the effect of alpha-tocopherol, one of the most potent vitamin E isomers, and SOD on the lipopolysaccharide (LPS)-induced increase in hepatic concentrations of N1-acetylspermidine. The LPS-induced increase in hepatic N1-acetylspermidine was more than twice as great in vitamin E-deficient mice as in vitamin E-supplemented mice. Pretreatment with alpha-tocopherol suppressed the LPS-induced increase in hepatic N1-acetylspermidine in vitamin E-deficient mice. Alpha-tocopherol and SOD given to mice maintained on a usual diet likewise suppressed the LPS-induced increase in hepatic N1-acetylspermidine and putrescine. The hepatic concentrations of alpha-tocopherol and GSH were lower in LPS-treated mice than in control animals. Diethyldithiocarbamate, an inhibitor of SOD, and diisopropylidene (phorone), a GSH-depleting agent, enhanced the LPS-induced increase in hepatic N1-acetylspermidine. These results suggest that the LPS-induced hepatic increase in N1-acetylspermidine is connected with radical-induced injury in vivo and that superoxide anion is produced in the liver of LPS-treated mice.

Animals↗

PubMed1989

Interconversion of polyamines in wild-type strains and mutants of yeasts and the effects of polyamines on their growth.

Yeasts of wild-type strains, such as Saccharomyces cerevisiae, Schizosaccharomyces pombe and Candida albicans were shown to have the ability to form aminopropylcadaverine and aminopropylhomospermidine from cadaverine and homospermidine, respectively. A polyamine autotroph S. cerevisiae 179-5, which lacks ornithine decarboxylase, produced both aminopropylcadaverine and aminopropylhomospermidine, while another mutant S. cerevisiae Y 260 A, which lacks spermine synthase, formed only aminopropylcadaverine. Naturally-occurring triamines and tetraamines except norspermidine and norspermine stimulated the growth of S. cerevisiae 179-5. All the six aliphatic diamines with carbon chain length ranging from one to six were effective in activating the growth of S. cerevisiae 179-5, though all of them were not converted to either triamines or tetraamines.

Candida albicans↗

PubMed1989

Superoxide dismutase and alpha-tocopherol suppress the paraquat-induced elevation of N1-acetylspermidine and putrescine in primary culture of adult rat hepatocytes.

A transient increase in N1-acetylpolyamines and putrescine (PUT) was observed in hepatocytes at the early stage of primary culture of rat hepatocytes. After pre-culture for 36 hr when the polyamine content returned to constant levels, we tested the effects of superoxide dismutase (SOD) and alpha-tocopherol on the paraquat-induced increase in N1-acetylspermidine (N1-acetyl-SPD) and PUT in the culture. Paraquat increased (N1-acetyl-SPD in a dose-dependent manner. It also increased PUT at doses between 0.1 and 1.3 mM. Both SOD and alpha-tocopherol suppressed the increase in N1-acetyl-SPD and PUT induced by paraquat. These results suggested that superoxide anion is one of the factors which increase N1-acetyl-SPD and PUT in hepatocytes. Lipopolysaccharide (LPS) little affected the polyamine concentration in the cultured hepatocytes, though it increases polyamine in mouse liver when given in vivo. These findings suggested that the formation of superoxide anion after administration of LPS in vivo is mediated by Kupffer cells.

Animals↗

PubMed1989

Distribution of spermine in bacilli and lactic acid bacteria.

Obligate moderately thermophilic bacilli and obligate moderately thermoacidophilic bacilli contained spermine as the major polyamine in addition to putrescine and spermidine. The identity of spermine was confirmed by thin-layer chromatography and high-performance liquid chromatography before and after treatment with putrescine oxidase. Using these methods, thermospermine and spermine can be separated; thermospermine was not present in these organisms. On the other hand, various facultative thermophiles and mesophilic strains of the genus Bacillus, including alkalophiles and halophiles, lack spermine and other tetraamines. No spermine was detected in several strains of mesophilic or facultative slightly thermophilic lactic acid bacteria, Lactobacillus and Streptococcus.

Bacillus↗

PubMed1989

Release of nucleosomes from nuclei by bleomycin-induced DNA strand scission.

Mononucleosomes were released from both isolated mammalian (hog thyroid) and protozoan (Tetrahymena) nuclei by the bleomycin-induced DNA-strand breaking reaction. Trout sperm nuclei, on the other hand, were protected from the bleomycin-mediated DNA degradation. The mononucleosomes released from the bleomycin-treated nuclei contained the core histones H2A, H2B, H3, and H4; while HMG1 and HMG2 proteins, in addition to the core histones, were detected in the mononucleosomes obtained by micrococcal nuclease digestion of nuclei. HMGs, but not H1 histone, were dissociated into the supernatant by cleavage of chromatin DNA with bleomycin, whereas both HMGs and H1 were found in that fraction by digestion of nuclei with micrococcal nuclease. HMG1 and HMG2 were exclusively dissociated from chromatin with 1 mM bleomycin under the solvent condition where the DNA strand-breaking activity of the drug is repressed. These observations suggest the possibility that bleomycin preferentially binds to linker DNA regions not occupied by H1 histone in chromatin and exclusively dissociates HMG proteins and breaks the DNA strand. The results of the effects on bleomycin-induced DNA cleavage of nuclei of various drugs including polyamines, chelating agents, intercalating antibiotics such as mitomycin C or adriamycin, and radical scavengers are also presented.

Animals↗

PubMed1987

Occurrence of aminopropylhomospermidine and canavalmine in the hamster epididymis.

The Syrian hamster epididymis contains rather high levels of sym-homospermidine, N1-acetylspermidine and N1-acetylspermine in addition to the common polyamines putrescine, spermidine, and spermine. In the present study two other polyamines were identified in adult hamster epididymis by gas chromatography; they are aminopropylhomospermidine [NH2(CH2)3NH(CH2)4NH(CH2)4NH2] and canavalmine [NH2(CH2)4NH(CH2)3NH(CH2)4NH2]. The molar ratio of the former to the latter was about 2:1. This is the first report to show that tetraamines other than spermine are present in mammalian tissues.

Animals↗