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Biomedical subjects

M Oshima

Publications and source records attributed to M Oshima.

At least 289 records · Page 16Linked to original sources
PubMed1977

Bacteriophage phiNS11: a lipid-containing phage of acidophilic thermophilic bacteria. II. Purification and some properties of the phage.

An improved procedure for the purification of a lipid-containing acidophilic thermophilic bacteriophage, phiNS11, is described. The procedure involves Cs2SO4 discontinuous density gradient, Cs2SO4 equilibrium density gradient and sucrose gradient centrifugations. The phage has an icosahedral shape, 75 nm in diameter, with spike-like structures radiating from the vertices. It contained about 12% by weight of lipid, 13--14% of DNA and 74--75% of protein. The phage was stable between pH 2 and 5, but rapidly inactivated above pH 6. It was highly sensitive to organic solvents and detergents. Some other basic properties such as the buoyant density and UV spectrum of the purified phage are also described.

Bacillus↗
PubMed1977

Bacteriophage phiNS11: a lipid-containing phage of acidophilic thermophilic bacteria. III. Characterization of viral components.

Components of a lipid-containing phage phiNS11 were characterized. The phage had five protein components, the molecular weights of which were 59,000, 44,000, 33,000, 23,000, and 18,000. Viral lipid consisted of six components, which were also found in the host bacterial lipid. The relative amounts of these viral lipid components were very similar to those of the bacterial lipid. The phage contained omega-cyclohexyl fatty acids characteristic of Bacillus acidocaldarius as the main fatty acids. The phage nucleic acid was a linear double-stranded DNA, the molecular weight of which was 9.3--9.4 X 10(6) daltons. The guanine plus cytosine content of the DNA was determined to be about 52% from chemical analysis, buoyant density (1.711 g/cm3 in CsCl) and melting temperature (90.6 degrees C in 0.15 M NaCl plus 0.015 M sodium citrate). The phage contained two kinds of polyamine; spermidine and spermine.

Bacillus↗
PubMed1977

A morphological and physiological study of mesotubarium ovarica in humans.

In order to clarify the mechanisms by which the egg is transported from the ruptured follicle into the fimbrial end of the Fallopian tube in the human being, the mesotubarium ovarica (MTO), the unique anatomical structure which connects the tubal fimbriae and the ovary, was studied in seven human adnexal specimens histochemically and electron microscopically. The results demonstrated clearly the presence of smooth muscle cells in the MTO, and failed to demonstrate the presence of cilia in the lining epithelial cells of the MTO. Based on these morphological results, contractility of the MTO was studied in vitro by using a muscle chamber and a pressure transducer with 26 human adnexal specimens. Spontaneous contractile activites of regular frequency and moderate intensity were observed in the MTOs of all specimens examined. A possible role of the MTO in the mechanisms of ovum pickup at the time of ovulation is discussed.

Adult↗
PubMed1977

Scanning electron microscopy of human female reproductive tract and amniotic fluid cells.

Scanning electron microscopy was used to examine surface ultrastructural characteristics of cells of the epithelium of female reproductive tract, cervical mucus, and amniotic fluid cells. The female epithelium undergoes hormone-dependent cyclical morphological alterations in cell shape, apical microvilli, ciliation, and secretory patterns. The frequency distribution of ciliated cells varies in different parts of the female reproductive tract and different segments of the same organ. In the endocervix, a few ciliated cells are randomly distributed. The density of ciliated cells is variable in several areas of the endometrium. The sparse distribution of ciliated cells in the central portion of the uterine wall may indicate a possible implantation site. According to surface ultrastructure of cells, three segments are noted in the uterotubal junction: cornual endometrium, interstitial tubal epithelium, and transitional area. The vaginal epithelium is made of flat polygonal cells with interdigitating borders and a fine interlacing network of microridges. After the menopause, the microridge pattern and distinct cell borders are lost or severely modified. Two types of fibrous structures can be found in cervical mucus: a) microfibrils that vary in diameter from 500 to 1,500 A and from bundles or networks, and b) long, thick fibers that vary in diameter from 0.5 to 5 micrometer run parallel to each other, and appear to be made up of microfibrils. Amniotic fluid cells, derived from amniotic epithelium and fetal ectoderm, consist of non-nucleated and nucleated cells with extensive microplicae.

Amniotic Fluid↗
PubMed1977

A morphologic study of mesotubarium ovarica in the human.

In order to clarify the mechanisms by which the egg is transported from the ruptured follicle into the fimbrial end of the fallopian tube in the human, the mesotubarium ovarica (MTO), the unique anatomic structure which connects the tubal fimbriae and the ovary, was studied in seven human adnexal specimens histochemically and electronmicroscopically. The results demonstrated clearly the presence of smooth muscle cells in the MTO, and failed to demonstrate the presence of cilia in the lining epithelial cells of the MTO. A possible role of the MTO in the mechanisms of ovum pick-up at the time of ovulation is discussed.

Adult↗
PubMed1976

Identification of glucosyl sphingosine from Gaucher's spleen by gas chromatography-electron impact and GC-chemical ionization mass spectrometry.

Glucosyl sphingosine was isolated from the spleen of a patient with adult-type Gaucher's disease. The yield of purified glucosyl sphingosine was 9.3 nmoles/g wet tissue. The gas chromatography-chemical ionization mass spectrum of acetylated glucosyl sphingosine showed peaks due to the presence of ions formed by successive loss of acetic acid (mass 60) from the molecular ion (QM+, 714). Fragments from acetylated sugar, m/e 331, and from the sphingosine residue, m/e 306, were also detected. The GC-CI mass spectrum of the trimethylsilyl derivative of glucosyl sphingosine showed peaks due to the molecular ion (QM+, 822), ions from the sugar moiety (m/e 361, 271), and ions from the sphingosine base (m/e 264, 280). Fragmentation analysis of the purified sample by GC-EI and GC-CI mass spectrometry confirmed the structure glucopyranosyl(1 leads to 1)-1,3-dihydroxy-2-amino-4-octadecene.

Adult↗
PubMed1975

Effects of thienodiazepine derivatives on human sleep as compared to those of benzodiazepine derivatives.

The effects of new thienodiazepine derivatives, such as clotiazepam and Y-7131, on normal human sleep were investigated on 5 subjects and compared to those of benzodiazepine derivatives, such as diazepam and nitrazepam. REM sleep was significantly decreased only with 2 mg of Y-7131 and rebound elevation of REM sleep did not follow in recovery 1 and 2 nights. By using partial differential REM deprivation which was designed by us, there was also no rebound elevation of REM sleep noted in recovery 2 nights following 2 mg of Y-7131 medication. REM sleep was not suppressed with 15 mg of clotiazepam, 6 mg of diazepam and 10 mg of nitrazepam when compared to the baseline night. With regard to NREM sleep, stage 2 was significantly increased with 15 mg of clotiazepam and 10 mg of nitrazepam, but stage SWS was significantly decreased with 10 mg of nitrazepam.

Adult↗
PubMed1975

Omega-cyclohexyl fatty acids in acidophilic thermophilic bacteria. Studies on their presence, structure, and biosynthesis using precursors labeled with stable isotopes and radioisotopes.

Omega-Cyclohexyl undecanoic acid and omega-cyclohexyl tridecanoic acid were found in 10 strains of acido-thermophilic bacteria isolated from different Japanese hot springs. These unusual fatty acids were found in the esterified form in glyceride type complex lipids and constituted 74 to 93% of the total fatty acids in the bacteria. The fatty acids other than omega-cyclohexyl fatty acids found were 14-methyl hexadecanoic acid (3 to 15%) and 15-methyl hexadecanoic acid (1 to 6%), and trace amounts of straight chain and methyl-branched tetra- and penta-decanoic acids. Biosynthesis of omega-cyclohexyl fatty acids increased with increase in the concentration of glucose in the culture medium. The metabolism of omega-cyclohexyl fatty acids was studied using deuterium-labeled precursors by mass fragmentation analysis. The deuterium of [2-D]glucose was specifically incorporated into position 2 of the cyclohexyl ring of the fatty acids, indicating that the ring was synthesized from the glucose molecule. Radioactivity was efficiently incorporated into the omega-cyclohexyl fatty acids from labeled glucose, shikimate, and cyclohexyl carboxylate. These findings indicate that omega-cyclohexyl fatty acids are synthesized with glucose through shikimic acid and probably cyclohexyl carboxylyl-CoA derivative as the intermediates.

Acetates↗
PubMed1975

Magnetorheography; calculation of blood flow from surface induced potentials.

This research is an attempt to measure blood flow without doing any hurt to the body. When the body is placed in a high magnetic field the blood-flow-induced electromotive force (EMF) can be detected with the surface electrodes using the same principle as an electromagnetic flow-meter. This blood flow measurement is named magnetorheography (its recording: MRG). A theoretical analysis of the potential in the tissue shows that blood flow can be calculated from the surface-induced EMF (MRG) without measuring the radius and the depth of the vessel from the skin surface, when the surface is fairly flat in the vicinity of the vessel. A model experiment verified the theory. In order to apply the theory to the measurement in an in situ situation, a structural coefficient was introduced which is related to the external shape, internal tissue compositions and their impedance of the body. Using such a coefficient the flow calculated from MRG, by an equation including the coefficient, agreed with the flow actually recorded. In experiments on the thighs of 8 dogs weighing 7 to 17 Kg, MRG proved to be proportional to arterial flow and the coefficients were approximately constant. These results indicate that blood flow may possibly be estimated by the calculation from MRG.

Animals↗
PubMed1975

DB-2073, a new alkylresorcinol antibiotic. I. Taxonomy, isolation and characterization.

A new antibiotic, DB-2073, was isolated in crystalline form from the fermented broth of Pseudomonas sp. B-9004. The compound is a alkylresorcinol antibiotic. The antibiotic melts at 86-88 degrees C. The molecular weight of 236 was determined by mass spectroscopy and the molecular formula was calculated as C15H24O2. The antibiotic has antimicrobial activity against Gram-positive bacteria, mycobacteria and fungi.

Anti-Bacterial Agents↗