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Biomedical subjects

Y Oda

Publications and source records attributed to Y Oda.

At least 577 records · Page 32Linked to original sources
PubMed1986

Isolation and characterization of a lectin from tulip bulbs, Tulipa gesneriana.

A lectin, which agglutinated specifically the yeast cells of the Saccharomyces genus, was isolated from tulip bulbs (Tulipa gesneriana) using affinity chromatography on mannan-Sepharose 4B. Its relative molecular mass was determined by gel filtration to be approximately 67,000. On polyacrylamide gel electrophoresis in sodium dodecyl sulfate, a relative molecular mass of 17,000 was obtained, suggesting that the lectin is a tetramer. Binding studies performed with iodinated lectin indicated that Saccharomyces cerevisiae cells contained approximately 5.7 X 10(6) binding sites per cell, whereas little binding was observed with yeasts other than the Saccharomyces genus, bacteria and animal erythrocytes. D-Mannose, D-mannose 6-phosphate, L-fucose and L-fucosylamine were potent inhibitors of the lectin binding to S. cerevisiae cells, while, D-glucose, D-galactose and D-mannosamine were inactive, indicating that hydroxyl group at C-2 of D-mannose was essential for the lectin binding. Furthermore, inhibition experiments, using various manno-oligosaccharides, suggested that the lectin recognized (1----6)-linked manno-oligosaccharide units larger than mannobiose.

Agglutination↗
PubMed1986

Nucleotide sequence of chick 14K beta-galactoside-binding lectin mRNA.

cDNA for chick 14K beta-galactoside-binding lectin mRNA was cloned and the nucleotide sequence determined. The deduced amino acid sequence and the results of in vitro translation of its mRNA suggest that this lectin does not include any cleavable signal sequence while it exists in extracellular matrix. Comparison of the primary structures has shown that chick 14K lectin includes some regions homologous to those in discoidin I, which is also known to be located in extracellular matrix and lack signal peptide. The results imply some relation between these two lectins in spite of their great phylogenetic separation.

Amino Acid Sequence↗
PubMed1986

Induction of SOS functions by nitrogen dioxide in Escherichia coli with different DNA-repair capacities.

The effect of gaseous nitrogen dioxide (NO2) on cytotoxicity, induction of synthesis of UmuC and RecA proteins, and mutagenesis was studied in Escherichia coli strains with different capacities of DNA repair. Gaseous NO2 (90, 180 microliter/l) killed Escherichia coli. The recA mutant was most sensitive, the lexA mutant moderately sensitive, and the uvrA mutant and the wild-type the least sensitive. When 90 microliter/l NO2 gas was bubbled into bacterial suspensions for 30 min at a flow rate of 100 ml/min, the induction of umuC gene expression increased in the wild-type strain. NO2 also induced the recA gene expression in the wild-type strain. The synthesis of neither RecA nor UmuC proteins was induced in the recA and lexA mutants. We further investigated the NO2 mutagenesis in the cells treated with bubbling of NO2 gas. NO2 caused mutation to Trp+ of WP2.

DNA Repair↗
PubMed1986

Synaptic currents at interpositorubral and corticorubral excitatory synapses measured by a new iterative single-electrode voltage-clamp method.

A new iterative single-electrode voltage clamp method was applied to the measurement of synaptic currents in the red nucleus (RN) neuron of the cat. Voltage clamp was attained within 10 repetitions with great stability and the new algorithm was demonstrated to be superior to the original algorithm of iterative voltage clamp. With a conventional microelectrode, it was possible to measure the synaptic current with the time resolution of 50 microseconds. The synaptic currents evoked by stimulation of the contralateral interpositus nucleus (IP) had time-to-peak ranging from 200 to 540 microseconds and fitted well to alpha functions. Corticorubral (CR) synaptic current was also measured by making use of synaptic plasticity. The stimulation of the ipsilateral cerebral peduncle in cats with chronic lesion of the contralateral IP evoked fast rising EPSPs, as reported previously. The CR-EPSPs with times-to-peak less than 1 ms were subjected to voltage clamp. The CR synaptic currents had times-to-peak ranging from 350 to 880 microseconds. Since most of the interpositorubral (IR) synapses and a part of the CR synapses in IP-lesioned cats are situated on the somatic membrane of RN neurons and some of the CR synaptic currents were as rapid as the IR synaptic currents, the observed synaptic currents evoked by stimulation of the IP and those of the fast-rising CR-EPSPs were taken to originate from the synaptic membrane under space-clamp, i.e. soma. The present study provided additional evidence for the sprouting of the CR fibers as well as the time course of the synaptic current at the dendritic synapses remote from the soma, for the first time.

Animals↗
PubMed1986

Monoclonal antibodies against a beta-galactoside-binding lectin of chick embryo.

Monoclonal antibodies against an endogenous beta-galactoside-binding lectin (monomer molecular weight 14,000, 14K lectin) of chick embryo were prepared and characterized. The inhibitory activities against hemagglutination, antigenic determinants and binding specificities were examined. Monoclonal antibody S1A4-5 strongly inhibited the hemagglutination activity of this lectin. This antibody did not bind to any cyanogen bromide (BrCN) fragment of the lectin. Another monoclonal antibody, S1A4-3, bound to one of the BrCN fragments (residues 34-66). However, this antibody inhibited hemagglutination only weakly. The bindings to isolectins of beta-galactoside-binding lectin, namely 14K lectin (monomer molecular weight 16,000) and a third species which is assumed to be a hybrid molecule consisting of 14K and 16K lectin subunits, were examined. The antibody SIA4-5 bound to 14K lectin but not to 16K lectin. In the case of the third species, intermediate binding was observed.

Animals↗
PubMed1986

The presence of intracytoplasmic confronting cisternae of the endoplasmic reticulum in osteosarcoma cells in interphase.

Confronting cisternae of the endoplasmic reticulum recognized in tumor cells of 7 cases of osteosarcoma were presented. They were found in the mitotic cells as well as in the cytoplasms of interphase cells. The more the mitotic cells were observed in 1 micron-thick sections, the more frequently those membranous structures were encountered in the corresponding ultrathin sections. In the interphase cells, such structures were located around Golgi apparatus or close to the nucleus. Occasionally, they were composed of a pair of closely apposed cisternae of the nuclear membrane and the rough endoplasmic reticulum. These results seem to indicate that the nuclear envelope which is disrupted and reformed during mitosis in rapidly proliferating cells takes part in the formation of the confronting cisternae of the endoplasmic reticulum.

Adolescent↗
PubMed1986

Papillary carcinoma of the thyroid gland with anaplastic transformation in the metastatic foci. An immunohistochemical study.

An immunohistochemical study was made on an autopsy case of papillary carcinoma of the thyroid with anaplastic transformation in the metastatic foci occurring in a 72-year-old woman. The anaplastic carcinoma cells were sarcomatous in appearance, and they were vimentin-positive and cytokeratin-negative. Whereas, papillary tumor cells which were intermingled in the anaplastic carcinoma contained both cytokeratin and vimentin. The close correlation between tumor cell anaplasia and the expression of the different intermediate filament proteins in thyroid carcinoma was briefly discussed.

Aged↗
PubMed1986

Selection of yeasts for breadmaking by the frozen-dough method.

Eleven yeast strains suitable for frozen dough were selected from over 300 Saccharomyces strains. All of these were identified as Saccharomyces cerevisiae from morphological, cultural, and physiological characteristics. The selected yeast cells accumulated a higher amount of trehalose than did commercial bakers' yeast cells.

Journal Article↗
PubMed1986

[Quantitation of coronary artery lesions by 2-4 hour stress-myocardial clearance of thallium-201].

The stress-redistribution thallium-201 scintigraphy and thallium-201 washout method have limitations in their ability to detect individual coronary lesions in patients with multivessel coronary artery disease. The purpose of this study is to investigate the value of the quantitative planar method using the dynamics of thallium-201 redistribution after exercise. We observed the patterns of thallium clearance in the late stages (at 2 and 4 hrs) which are characteristic of decreased myocardial blood supply by the obstructed coronary arteries. In 20 subjects, quantitative thallium scintigrams (planar image and circumferential count profile) and blood samples for thallium concentration were obtained immediately, and 2 and 4 hrs after maximal treadmill exercise. Coronary angiography was performed in all subjects, and 16 patients had coronary artery disease (CAD) and four were normal. The rate of thallium clearance from the blood (TCB) was compared with the rate of thallium clearance from each segmental lesion of the myocardium (TCM) between the 2- and 4-hr images. The system adopted for assignment of myocardial regions to individual coronary arteries has been used as an approach to localization of anatomic disease. In the four patients with normal coronary arteries, TCM exceeded TCB in all regions of all images (specificity 100%). Fourteen of the 16 CAD patients had at least one region where TCM was less than TCB (sensitivity 88%). Ten of the 14 patients with multivessel CAD had multiple regions where TCM was less than TCB (sensitivity 71%). All of the six patients without multivessel CAD (four with normal coronary arteries and two with one vessel disease) did not have multiple regions where TCM was less than TCB (specificity 100%). Quantitative thallium scintigraphy showed sensitivities of 86%, 56% and 91% in the left anterior descending artery, the circumflex coronary artery and right coronary artery, respectively. These results showed that decreased TCM in the late stage is characteristic of myocardial regions where blood is supplied by the diseased coronary arteries. This finding may improve diagnostic sensitivity under the condition of multivessel coronary artery disease.

Adult↗
PubMed1986

[Nocardia brain abscess and ventriculitis--resistance of Nocardia to sulfonamides and susceptibility to beta-lactams].

A 31-year-old man had been healthy until the end of August, 1984 when he developed a sore throat, rhinorrhea, and high fever (39 degrees C). He was found to have hematuria and leukocytosis, though his complaints were not severe, and was not absent from his work. From the September 30, he experienced continuous pains on both temple regions and the neck. On October 6, he visited our hospital without any inflammatory signs. A screening CT scan demonstrated a ring-like enhancing mass with remarkable perifocal edema in the right temporal lobe. On emergency admission on October 9, a low grade fever (37.4 degrees C) and slight leukocytosis were noted, but not other primary lesions were present. He had normal immunological function of both humoral and cellular types. A provisional diagnosis of malignant brain tumor was made, but a possibility of brain abscess was not completely ruled out. He was initially treated with antidiuretics and steroid with prophylactic antibiotics, and underwent follow-up CT scanning. After a 10-day period with no obvious changes in CT scan, he suddenly complained of severe headache and fever, and became stuporous. A subsequent CT scan showed signs of ventriculitis, and contrast-enhancing multiloculated capsules. A lumber puncture revealed an increased number of cells, and concentration of protein in the CSF. An emergency trephination and drainage of an abscess was performed. Gram positive, acid fast, and branching fungi were found in both the smear of pus, and the samples from surrounding brain tissues. These were later identified as Nocardia asteroides in bacteriological studies.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗