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M Toda

Publications and source records attributed to M Toda.

At least 181 records · Page 10Linked to original sources

Adherence of Fusobacterium necrophorum to Vero cells.

The adherence of the anaerobic species Fusobacterium necrophorum to the surface of Vero cells was studied. Adherence between the bacterium and the tissue culture cells was paralleled by the hemagglutinability of F. necrophorum. Treatment of the bacterial cells with lactoalbumin hydrolysate or anti-F. necrophorum-hemagglutinin serum reduced the intensity of the attachment. The purified hemagglutinin bound to the membranes of Vero cells. It lost its adherent property when mixed with the homologous anti-hemagglutinin serum. These observations suggest that the adherence of F. necrophorum to the surface of Vero cells is mediated by the bacterial hemagglutinin.

Adhesiveness↗

Transposon-like sequences in extrachromosomal circular DNA from mouse thymocytes.

Small polydisperse circular (spc) DNA was isolated from mouse thymocytes and cloned into the HindIII site of lambda vector Charon 7. Fifty-six recombinants from this spc DNA library were analyzed. R repeats, which were originally found near immunoglobulin genes, were enriched in spc DNA clones relative to their representation in the chromosome. In one clone, the R sequence was linked to Bam and MIF sequences and the contiguous arrangement was truncated from both ends. In another clone, composite Bam/R and R repeats existed as a pair in inverted repeat orientation. Truncation occurred from the 5' side without affecting the 3' ends. In both clones, short direct repeats flanked the repeated sequences. The possible role of R sequences in transposition and circular formation is discussed.

Animals↗

In vitro studies on the antibacterial activities of YM-13115, a new broad-spectrum cephalosporin.

The in vitro antibacterial activities of YM-13115, a new parenteral cephalosporin, were compared with those of ceftazidime, cefoperazone, and cefsulodin. The compound was highly active against the common members of the Enterobacteriaceae and 2 to 256 times more active than cefoperazone. YM-13115 was as active as ceftazidime against Citrobacter freundii, Proteus vulgaris, and Morganella morganii and two to four times more active than ceftazidime against Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Enterobacter aerogenes, Serratia marcescens, Proteus mirabilis, Providencia rettgeri, and Providencia stuartii. The activity of YM-13115 against Pseudomonas aeruginosa (with MICs of 0.78 and 3.13 micrograms/ml for 50 and 90% of the isolates, respectively) was ca. 2 times that of ceftazidime, 4 times that of cefsulodin, and 16 times that of cefoperazone. Against Haemophilus influenzae YM-13115 was more active than ceftazidime. YM-13115 was less active than ceftazidime, cefoperazone, and cefsulodin against Staphylococcus aureus and Staphylococcus epidermidis. The concentrations of YM-13115 required to inhibit the growth of 90% of the isolates of Streptococcus pyogenes and Streptococcus pneumoniae were 0.78 and 1.56 microgram/ml, respectively, but concentrations above 100 micrograms/ml were required to inhibit Streptococcus faecalis. YM-13115 was not hydrolyzed by the common plasmid and chromosomal beta-lactamases. YM-13115 is extremely active against P. aeruginosa and members of the Enterobacteriaceae.

Bacteria↗

Purification and partial characterization of Fusobacterium necrophorum hemagglutinin.

Hemagglutinin (HAin) of Fusobacterium necrophorum was separated from the bacterial cells by trypsinization-sonication, and purified by the gel filtration on Sephadex G-100 column. The final product obtained from gel filtration gave one precipitin line in the immunodiffusion gel and produced a single band in polyacrylamide gel electrophoresis. The molecular weight of the HAin was estimated to be about 19000 by sodium dodecyl sulfate polyacrylamide gel electrophoresis. It was heat labile and comparatively rich in alanine, glutamine and histidine. Electron microscopy observation revealed that the HAin was a filamentous rod with 0.5-1.0 nm width or frequently showed a cluster form. The hemagglutinability was inhibited by addition of albumins but not by sugars and lipopolysaccharide. Anti HAin rabbit serum inhibited hemagglutination.

Amino Acids↗

Isolation of obligate anaerobic bacteria from bovine abscesses in sites other than the liver.

A survey in Japan showed that of 2036 slaughtered cattle 58(3%) had abscesses in sites other than the liver. In 21 of the affected animals the lesions were pulmonary and in 32 abdominal (excluding hepatic); in five animals the lesions were found elsewhere (muscle 2, skin 2, bone 1). Nineteen (33%) of the 58 cattle also had abscesses in the liver. Obligate anaerobes alone were isolated from 17(29%) of the affected animals (Fusobacterium necrophorum 14, Bacteroides spp. 2, Peptostreptococcus anaerobius 1). A mixture of obligate anaerobes and aerobes or facultative anaerobes was isolated from 31 affected cattle: of these animals 21 yielded large and five small numbers of F. necrophorum; three yield fusobacteria other than F. necrophorum; and two yielded Propionibacterium acnes. The remaining 10 affected animals yielded only aerobes or facultative anaerobes. The numbers of viable obligate anaerobes in pus specimens were in the range 10(3)-10(9)/ml.

Abscess↗

Purification of small polydisperse circular DNA of eukaryotic cells by use of ATP-dependent deoxyribonuclease.

Small polydisperse circular (spc) DNAs of mouse thymocytes were purified by a procedure involving nitrocellulose column chromatography and the treatment of ATP-dependent DNase, which acts only upon linear DNA molecules. Nitrocellulose column chromatography prior to the enzyme treatment was essential because digestion of linear DNA duplexes by the enzyme was inhibited by the presence of concomitant single-stranded DNAs. Mitochondrial DNAs were eliminated by linearization with XhoI and digestion with ATP-dependent DNase. The size distribution of the purified spc DNA molecules ranged from 0.2 micron to more than 28 micron, with a mean length of 5.4 micron. Circular molecules of more than 0.4 micron long (or 1.2 kb) were free from the contamination of linear DNA fragments and pure enough to be cloned into plasmids.

Animals↗

Synthesis and 5-lipoxygenase inhibitory activities of eicosanoid compounds.

Ten eicosanoid compounds (3, 6, 9, 11, 12, 15, 18, 21, 23, and 25), methyl (6E,8Z,11Z,14Z)-5-hydroxy-6,8,11,14-eicosatetraenoate (5-HETE, 10), leukotriene A4 (26), and (5S,6E,8E,10E,12RS,14E)-5,12-dihydroxy-6,8,10,14-eicosatetraenoic acid (5,12-diHETE, 27) were prepared and their inhibitory activities against the 5-lipoxygenase from guinea pig polymorphonuclear leukocytes (PMNL) were tested. 5,6-Methanoleukotriene A4 (18) was especially a potent and specific inhibitor of the 5-lipoxygenase without inhibiting the cyclooxygenase and the 12-lipoxygenase. Leukotriene A4, 5-HETE, and 5,12-diHETE also have inhibitory activities against the 5-lipoxygenase at micromolar concentrations, which can regulate the formation of slow-reacting substance of anaphylaxis intracellulary.

Animals↗

Thymidine factor in human cord sera and relationship to birth size, gestational age and insulin.

Thymidine factor was studied in human cord sera from 44 neonates with gestational ages ranging between 36 and 43 weeks. Thymidine factor was determined by the uptake of 6-3H-thymidine using isolated chick embryo cartilage cells. The thymidine factors increased with gestational age and those of neonates at 40 weeks of gestation were 0.89 +/- 0.17 U/ml (mean +/- SD), but were significantly lower after 42 weeks of gestation. There was no correlation between thymidine factor in cord sera and birth weight or size. There was a positive correlation (p less than 0.02) between insulin level and thymidine factor in cord sera. Our data suggest that somatomedin measured as thymidine factor might not have a major role in fetal growth and insulin might be an important factor in the synthesis of somatomedin by the fetus.

Birth Weight↗