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Biomedical subjects

Y Oda

Publications and source records attributed to Y Oda.

At least 559 records · Page 31Linked to original sources
PubMed1988

[Nutritional assessments in the long-term survivors following massive resection of the small intestine].

Nutritional assessments were measured in the sixteen long-term survivors who had undergone a massive resection of more than two-thirds of the small intestine or less than 170 cm of the remaining small intestine. Prealbumin, retinol binding protein and zinc in serum and arm muscle circumference were significantly lower than the normal range. Serum albumin had a tendency to correlate to the length of the remaining small intestine. Nutritional risk index had a correlation with the length of the remaining small intestine. In this study, nutritional assessments in the patients with a massive resection of the small intestine indicated to be in preclinical malnutritional state. This may support that supplementary nutritional therapy is necessary for such patients. In addition, we reported a patient with sensory polyneuropathy caused by vitamin E deficiency due to short bowel syndrome. The level of vitamin E was low in his serum, 294 micrograms/dl (normal: 1004 +/- 65) and in his red blood cells, 136 micrograms/dl (normal: 176 +/- 9). His symptom was markedly decreased within two weeks after the administration of large doses of vitamin E.

Adolescent↗
PubMed1987

Formation of new corticorubral synapses as a mechanism for classical conditioning in the cat.

An electron microscopic quantitative study of corticorubral synapses was performed in the cat which acquired classical conditioning. Conditioned stimulus was applied to the cerebral peduncle and the unconditioned stimulus was an electrical shock to the forelimb skin. The proportion of corticorubral synapses contacting with somata and proximal dendrite was increased after conditioning. It was suggested that collateral sprouting and the formation of new synapses underlie classical conditioning.

Animals↗
PubMed1987

Immunological cross-reactivity between beta-galactoside-binding lectins of vertebrates. Possible relationship of antigenicity to oligomeric structure.

Structural relationships among five beta-galactoside-binding lectins isolated from human, mouse and chick were studied using immunochemical methods. The lectins examined were human placenta lectin with a 14-kDa subunit (human 14K lectin), two types of mouse lectin (mouse 15K and mouse 16K lectin), and two types of chick lectin (chick 14K and chick 16K lectin). Five polyclonal antibodies raised against these lectins were used. Antibody to human 14K lectin cross-reacted with mouse 15K and chick 14K lectins. Antibodies to both mouse 15K and chick 14K lectins cross-reacted with human 14K and chick 16K lectins. Antibody to chick 16K lectin cross-reacted with mouse 15K lectin. An immunological relationship was not found between human 14K and chick 16K lectins, or between mouse 15K and chick 14K lectins. Mouse 16K lectin did not show any immunological relationship with any of the other lectins. A monoclonal antibody raised against chick 14K lectin cross-reacted with chick 16K lectin. These results cannot be explained simply in terms of phylogenic distance but suggest that vertebrate beta-galactoside-binding lectins can be classified into two structural groups on the basis of their antigenicities. One group, which is characterized as a monomer type, includes human 14K and chick 14K lectins. The other group, which is characterized as a dimer type, includes mouse 15K and chick 16K lectins.

Animals↗
PubMed1987

Ultrastructural observations of the development of the fourth ventricular roof in the mouse brain.

The developmental changes of the fourth ventricular roof of the brain in mouse fetuses and neonates were observed by scanning and transmission electron microscopy with particular attention to the caudal portion where a median foramen might be formed during the fetal period. The fourth ventricular roof was continuously paved with a single layer of cuboidal or squamous neuroepithelial cells with poorly developed basement membrane until the 12th intrauterine day when the primitive choroid plexus appeared at the middle portion of the roof. With development of the choroid plexus, the roof caudal to the choroid plexus (membranous roof) became thinner, and it was mostly lined with a single layer of flat ependymal cells having cilia and microvilli and resting on a continuous basement membrane. These ependymal cells were connected with one another by a gap junction or an intermediate junction for the entire period examined, except at the 13th to 14th intrauterine days, during which the interependymal clefts were transiently widened up to 2 microns in width, in places, without disruption of the continuous basement membrane. Neither a median aperture nor wide intercellular pores were formed in the membranous roof during the fetal or neonatal term.

Animals↗
PubMed1987

A new agglutinin from the Tulipa gesneriana bulbs.

Two agglutinins with different agglutinating activity exist in Tulipa gesneriana bulbs. One is the T. gesneriana lectin which agglutinates yeasts as reported previously [Oda, Y. and Minami, K. (1986) Eur. J. Biochem. 159, 239-245]. The other agglutinin is a new one which agglutinates animal erythrocytes and was purified from the tulip bulbs using affinity chromatography on thyroglobulin-Sepharose 4B. The agglutinin agglutinated mouse and rat erythrocytes at a minimum concentration of 2 micrograms/ml and 30 micrograms/ml respectively, but did not agglutinate erythrocytes from other animals and yeasts even at a concentration of 1000 micrograms/ml. The agglutinin appeared homogeneous by disc gel electrophoresis at pH 4.3 and gel filtration. Its relative molecular mass was determined by gel filtration to be approximately 40,000. It was suggested that the agglutinin was composed of two different subunits of 26 kDa and 14 kDa by sodium dodecyl sulfate/polyacrylamide gel electrophoresis analysis. Binding of radioiodinated agglutinin to mouse erythrocytes indicated that the presence of a high-affinity site with a dissociation constant of 2.00 X 10(-9) M. In inhibition experiments thyroglobulin glycopeptides were the most potent inhibitors; thyroglobulin was also a potent inhibitor. Orosomucoid and mucin showed weak inhibition. The other glycoproteins, glycopeptides and sugars examined showed no inhibition.

Agglutination Tests↗
PubMed1987

Identification of I:A mismatch base-pairing structure in DNA.

Deoxyoligonucleotides containing deoxyinosine residues at positions corresponding to ambiguous nucleotides derived from an amino acid sequence have been successfully used as hybridization probes. It is assumed that the hypoxanthine residue can make base pairs with multiple bases. In order to obtain direct evidence for I:A base-pairing, a self-complementary deoxyoligonucleotide, d(G-G-I-A-C-C), was synthesized and its properties were examined by NMR spectroscopy. Three hydrogen-bonded imino proton resonances are observed at low temperatures in H2O suggesting the formation of a self-duplex with complete base pairing. Nuclear Overhauser effect (NOE) experiments showed that a signal at 15.1 ppm originated from the imino proton (H1) of the dI residue (I3) which is hydrogen-bonded to the dA residue (A4). Both the I3 and A4 residues were assumed to have taken an anti glycosidic conformation since irradiating the H1 of I3 gave NOEs both to its own H2 and to that of A4, an NOE also being observed between the H2 protons of I3 and A4. Comparison of the 31P NMR spectra of d(G-G-I-A-C-C) and d(G-G-I-C-C-C) showed the backbone structure of d(G-G-I-A-C-C) to have been disturbed by the presence of purine:purine base pairs in the middle of the hexamer duplex.

Base Composition↗
PubMed1987

Ultrastructure of the caudal portion of the fourth ventricular roof in the mouse.

A scanning and transmission electron microscopic study was done of the caudal portion of the fourth ventricular roof in the adult mouse. The caudal portion of the fourth ventricular roof was divided into two parts: choroid plexus and nonchoroid plexus roof. The plexus epithelial cells had numerous microvilli and were connected with each other with a tight junction, gap junction, or zonula adherens. The nonchoroid plexus roof was a thin neuroglial membrane with a continuous basement membrane, which we designated as "the membranous roof." The membranous roof was mostly composed of a single layer of paving ependymal cells supported by discontinuous pial cells. The ependymal cells were characterized by their squamous cell configuration, various numbers of microvilli and cilia, and a continuous basement membrane. They were connected with each other by gap junctions or zonulae adherentes, but they lacked tight junctions. Neither a cytoplasmic pore nor a wide intercellular cleft was identified. Neuronal and glial cell processes were occasionally observed. The aperture that is supposed to exist in the caudal, median portion of the fourth ventricular roof of the adult mammalian brains, called the foramen of Magendie in the human brain, was not found. Our observations suggest that the membranous roof itself would permit passage of the cerebrospinal fluid containing macromolecules via the interependymal cell clefts, implying that the foramen of Magendie would not be an anatomical aperture but a functional channel for the outflow of the cerebrospinal fluid.

Animals↗
PubMed1987

SOS-inducing activity of chemical carcinogens and mutagens in Salmonella typhimurium TA1535/pSK1002: examination with 151 chemicals.

The umu test system is a newly developed method to evaluate genotoxic activities of a wide variety of environmental carcinogens and mutagens (Oda et al., 1985). In the present study, we further examined the abilities of 151 chemicals to induce umu gene expression in Salmonella typhimurium TA1535/pSK1002. Among the chemicals examined, 72 compounds induced umu gene expression, which could be defined on a basis of increased beta-galactosidase activity by 2-fold over the background level. The potent genotoxic compounds without metabolic activation were adriamycin, bleomycin, daunorubicin, 1,3-dinitropyrene, 1,6-dinitropyrene, 1,8-dinitropyrene, N-ethyl-N'-nitro-N-nitrosoguanidine, furylfuramide, methyl methanesulfonate, N-methyl-N'-nitro-N-nitrosoguanidine, mitomycin C, 1-nitropyrene and 4-nitroquino-line-1-oxide. In the presence of S9, aflatoxin B1, 2-aminoanthracene, Glu-P-1, IQ, MeIQ, MeIQx, Trp-P-1 and Trp-P-2 also induced umu gene expression markedly. Several chemicals such as 2-acetylaminofluorene, 9-aminoacridine, azobenzene, benzanthracene, benzidine, diethyl nitrosamine, 1-nitronaphthalene, paraquat, potassium dichromate and sodium nitrite were weakly genotoxic and the induction by these compounds could be detected only when the incubation time was prolonged from 2 h to 5 h. Data are also presented that some of the chemicals such as dimethyl sulfoxide, m-dioxan, 5-fluorouracil and paraquat, which have been reported to be non-mutagenic in Ames/Salmonella assay, were found to be active in inducing umu gene expression, while the known mutagenic compounds including acrylonitrile, 4,4'-dinitrobiphenyl, furfural, methylene chloride, 1-naphthylamine, sodium azide, o-tolidine and o-toluidine were non-genotoxic in the present assay system.

Biotransformation↗
PubMed1987

Induction of SOS responses in Escherichia coli by 5-fluorouracil.

The inducibility of SOS responses by 5-fluorouracil (5-FU), which has been used as an antitumor drug, was studied in Escherichia coli cells which have different DNA repair capacities for UV lesions. Expression of the umuC gene was apparently induced by 5-FU in the wild-type and uvrA strains, but not in lexA and recA strains. The inducibility of the umuC gene by 5-FU, the metabolite of which inhibits thymidylate synthetase, was abolished in cultures containing deoxythymidine monophosphate which is converted from deoxyuridine monophosphate by thymidylate synthetase. These results suggest that 5-FU may exert its SOS inducibility by inhibiting thymidylate synthetase and then disturbing DNA metabolism but not by incorporating 5-FU residues into RNA. Further, 5-FU weakly induced mutations in E. coli.

DNA Repair↗
PubMed1987

Effect of N-benzyl-D-glucamine dithiocarbamate on distribution and excretion of cadmium in rats.

The effect of sodium N-benzyl-D-glucamine dithiocarbamate (NBG-DTC) on the distribution and excretion of cadmium in rats exposed to cadmium and the chemical form and intestinal reabsorption of cadmium compound excreted in the bile were studied. Rats were injected intraperitoneally with 109CdCl2 (1 mg Cd and 10 microCi 109Cd/kg) and 24 h later, they were injected with NBG-DTC (400 or 1200 mumol/kg). The biliary excretion of cadmium was remarkably increased by intraperitoneally injection of NBG-DTC, while there was only a small increase in urinary excretion of cadmium. Such an enhancement effect of NBG-DTC on the biliary excretion of cadmium was much larger at the high dose (1200 mumol/kg) of NBG-DTC. The treatment with NBG-DTC significantly decreased the cadmium content in the liver at the dose of 1200 mumol/kg and did not result in the undesirable redistribution of cadmium to the tissues, such as brain, testes, heart and lung. In addition, it was found that the cadmium compound excreted in the bile was mainly characterized as cadmium-NBG-DTC and which was not reabsorbed from the intestinal tracts.

Animals↗
PubMed1987

Systemic mastocytosis without cutaneous involvement.

An autopsy case of systemic mastocytosis without cutaneous involvement in a 76-year-old woman was described. The patient presented with general malaise, chest and epigastric discomfort, flushing of the face and progressive hepatosplenomegaly, and she terminated in hemorrhagic complications of DIC within 2 months. There was neither rash nor urticaria pigmentosa recognizable in the entire course. The diagnosis was made by the histologic identification of abnormal aggregates of mast cells in a bone marrow aspirate. These mast cell granules were chloroacetate esterase-positive, peroxidase-negative, and electronmicroscopically they were composed of fine granular materials containing variable numbers of lamellar structures. At autopsy, diffuse infiltration of the mast cells was found in the liver, spleen, bone marrow, lymph nodes, lungs, kidneys, stomach, and adrenal glands.

Aged↗
PubMed1987

L-methionine enhances the contractile response to norepinephrine of rat vas deferens.

Under Ca-depleted conditions, the contractile responses of rat vas deferens in the presence of norepinephrine were not elicited until the addition of CaCl2. L-Methionine enhanced the contractile response of vas deferens in the presence of methylation blockers under these conditions. The enhancing effect of L-methionine on some other smooth muscles could not be determined because under Ca-depleted conditions, these muscles showed 60-80% of the maximal contractile response on addition of CaCl2 alone. These findings suggested that L-methionine has an enhancing effect on contraction of the rat vas deferens as it does on rat uterine muscle.

Animals↗
PubMed1987

Physiological roles of two enzymes with fumarase activity in two Pseudomonads.

Effects of Fe2+ ions on the levels of two enzymes (fumarase and mesaconase) with fumarase activity in two Pseudomonads grown under various nutritional conditions were investigated. Fe2+ ions decreased fumarase but increased mesaconase. A high level of mesaconase was found in Ps. arvilla which was unable to metabolize itaconate. The level of mesaconase in the itaconate-grown cells of Ps. fluorescens was almost the same as that in the glucose-grown cells. This suggests that mesaconase is not an enzyme involved in the metabolism of C5-branched-chain dicarboxylates but presumably, taking the place of fumarase, plays a role in the operation of the tricarboxylic acid cycle in the cells grown in the medium containing Fe2+ ions more than 10 nmol/ml.

Ferrous Compounds↗