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Biomedical subjects

M Sugai

Publications and source records attributed to M Sugai.

At least 109 records · Page 6Linked to original sources
PubMed1991

Incidence and characterization of Staphylococcus aureus from the tongues of children.

Three hundred and seven children who had no diseases other than dental disease were examined for their oral carriage of Staphylococcus aureus, the most common persistent human pathogen. Eighty-four percent of them were positive for staphylococci, and 33% were positive for S. aureus. Among the 100 strains of S. aureus isolated, 40 strains produced enterotoxin, and 19 strains produced exfoliative toxin. Their susceptibility to antibiotics was also investigated: Six strains demonstrated resistance to methicillin (MIC greater than or equal to 12.5 microgram/mL), and 50% of the isolates were borderline resistant (MIC of 3.13 to 6.25 micrograms/mL) to the drug. These data suggest that the mouths of children could be reservoirs of pathogenic S. aureus.

Child, Preschool↗
PubMed1990

A novel epidermal cell differentiation inhibitor (EDIN): purification and characterization from Staphylococcus aureus.

A factor inhibiting the calcium-induced terminal differentiation of cultured mouse keratinocytes was purified to homogeneity from the extracellular products of S. aureus E-1 and designated 'epidermal cell differentiation inhibitor' (EDIN). EDIN activity was sensitive to trypsin and heat-labile, suggesting that EDIN is a protein. EDIN gave a single band with a molecular weight of 27,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and was found to be a single chain polypeptide, having an isoelectric point higher than 9. The N-terminal amino acid sequence of EDIN was determined as A-D-V-K-N-F-T-D-L. EDIN inhibited the differentiation of not only mouse but also human keratinocytes in culture.

Amino Acids↗
PubMed1990

A triazine dye, cibacron blue 3G-A induces Staphylococcus aureus to form giant clusters.

Cibacron blue 3G-A (CB), one of the triazinyl dyes commonly used as a ligand for affinity chromatography, induced staphylococci to form giant clusters without affecting cell viability. It was demonstrated that the cluster formation was not a mechanical aggregation of cells by CB, but a consequence of its biological effect on staphylococcal growth. Clusters induced by CB did not form a regular arrangement, and were different from clusters induced by SDS or polyanethole sulfonate.

Cell Division↗
PubMed1990

Purification of staphylococcal exfoliative toxin by high pressure liquid chromatography.

Exfoliative toxin (ET) isolated from a clinical strain of Staphylococcus aureus was purified to homogeneity, using a 3-step HPLC system. NH2-terminal 20 amino residues of purified ET was found to be identical with ETA of S. aureus TA (7), S. aureus TC16 (9) and S. aureus ZM (10), but stability of purified ET was completely different from that of ETA. This purification system gave a high yield of pure ET, which exhibited higher purity than specimens purified by more complicated and time-consuming procedures. It is useful for small-scale purification for the comparative study of ET and easy to scale up for preparative purification.

Amino Acid Sequence↗
PubMed1990

Adherence of Staphylococcus aureus to cultured epidermal cells during differentiation.

The adherence of clinical isolates of Staphylococcus aureus to cultured mouse epidermal cells was studied. Adherence of the isolates to the cells varied from strain to strain. When epidermal cell differentiation was induced by raising the calcium concentration in the medium, three out of 10 strains tested adhered better to calcium-induced differentiated cells than to undifferentiated cells, and one strain demonstrated higher adherence to undifferentiated cells than to differentiated cells. No significant difference between the adherences to both types of epidermal cells was observed with the other six strains. No relationship was observed between adherence and surface hydrophobicity with bacterial cells. Lipoteichoic acid and N-acetyl sugars caused limited inhibition of adherence. The adherence assay method employed in this study is useful for investigating the effects of epidermal cell differentiation on bacterial adherence in vitro.

Animals↗
PubMed1990

Characterization of sodium dodecyl sulfate-stable Staphylococcus aureus bacteriolytic enzymes by polyacrylamide gel electrophoresis.

Profiles of the bacteriolytic activities of Staphylococcus aureus culture supernatants, sodium dodecyl sulfate cell extracts, LiCl cell extracts, cell wall extracts, and cell membranes were analyzed in sodium dodecyl sulfate-polyacrylamide gels containing Micrococcus luteus or S. aureus. A total of 20 distinct bands of bacteriolytic activity could be detected in gels containing M. luteus, 8 of these bands were found in culture supernatants. The sodium dodecyl sulfate cell extracts, the LiCl cell extracts, and the cell membranes each contained 20 bands (P1 to P20), but no activity was found in cell wall extracts. Less bacteriolytic activity could be detected in gels containing S. aureus, although three bands were found in culture supernatants and LiCl extracts and cell membranes contained one major band, P13. Crude cell extracts showed five bacteriolytic bands of which the major bacteriolytic bands were distributed in an identical manner in all 10 strains of S. aureus studied. The effects of chemical and physical factors were determined, and it was shown that iodoacetic acid, Hg2+, and Cibacron Blue 3G-A reduced activity, and an optimum pH for enzyme detection was between 7 and 8. Preincubation at 100 degrees C for 30 min reduced the activity of P1 and P2 bands.

Bacteriolysis↗
PubMed1990

Relationship between gastrin cell number, serum, antral mucosa and luminal gastrin concentration and gastric acidity in antral atrophic gastritis.

The aim of our study was to investigate the relationship between gastrin producing cell density with antral mucosa, luminal and serum gastrin concentration in antral atrophic gastritis. Our study group consisted of 17 patients: six with mild atrophic gastritis, seven with moderate atrophic gastritis and four with severe atrophic gastritis. None of the patients had type-A atrophic gastritis but the body mucosa was affected by superficial gastritis at various extent in some. A group of 15 healthy subjects served as control. All subjects underwent gastroscopic examination with multiple bioptic sampling. Radioimmunoassay was used for gastrin determination and photomicroscopy for gastrin producing cell density assessment. Electron microscopy was used to assess the gastrin producing granule density index. Patients with moderate and severe atrophic gastritis showed a lower gastric acidity and acid output as compared to control. Serum gastrin did not show significant differences among the groups. In moderate and severe atrophic gastritis, gastrin producing cell granule density index, gastrin producing cell density and antral mucosa gastrin concentration were significantly lower when compared with control and decreased with advancing of the severity of atrophic gastritis. In atrophic gastritis, however, the latter two measurements were not correlated. In moderate and severe atrophic gastritis luminal gastrin concentration significantly increased, compared with control, after the severity of atrophic gastritis. Gastrin producing cell granule density index and luminal gastrin concentration showed a significant correlation with gastric pH. These data suggest that in antral atrophic gastritis with reduced gastric acidity, the decrement of gastrin producing cells is followed by gastrin producing cell hyperfunction with increased luminal release of gastrin.

Adult↗
PubMed1989

Purification of a 51 kDa endo-beta-N-acetylglucosaminidase from Staphylococcus aureus.

A bacteriolytic enzyme obtained from the culture fluid of Staphylococcus aureus FDA 209P was purified to homogeneity utilizing dye-ligand affinity column chromatography, hydrophobic interaction high pressure liquid chromatography (HPLC) and hydroxyapatite HPLC. Subsequent characterizations indicated that the purified enzyme acted as endo-beta-N-acetylglucosaminidase. The molecular weight determined by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) was 51,000 and the isoelectric point was higher than 10. The optimum pH for the enzyme activity on whole cells of Micrococcus luteus as a substrate was 8.0. Some heavy metal cations (Cu2+ and Zn2+) inhibited the enzyme activity at a concentration of 0.1 mM and others (Ba2+, Mg2+ and Co2+) showed a stimulating effect at a concentration of 1 mM.

Acetylglucosaminidase↗
PubMed1989

Aminoglycosides enhance the adherence of Staphylococcus aureus to HeLa cells.

Sub-lethal concentrations of aminoglycosides enhanced the adherence of Staphylococcus aureus FDA 209P to HeLa cells, whereas beta-lactams, pyridone carboxylic acid derivatives and chloramphenicol did not. Treatment with aminoglycosides also enhanced the bacterial adherence of these cells to immobilized fibronectin and laminin, and changed the bacterial cell surface to a more hydrophilic state than exists in non-treated cells. The adherence of S. aureus was not inhibited by lipoteichoic acid, extracted from the same strain, regardless of whether the bacterial cells were treated with an aminoglycoside or not. No correlation was observed between the adherence and zeta-potential of S. aureus.

Aminoglycosides↗
PubMed1987

Effects of mucopolysaccharides on penicillin-induced lysis of Staphylococcus aureus.

Effects of four mucopolysaccharides and dextran sulphate on penicillin-induced lysis of Staphylococcus aureus FDA 209P were studied. Heparin and dextran sulphate inhibited lysis, whereas hyaluronic acid enhanced it. Chondroitin sulphates A and C had no effect. Incubation of S. aureus suspended in 0.03 M phosphate buffer (pH 7.0) with dextran sulphate inhibited autolysis of the bacteria, whereas incubation with hyaluronic acid enhanced autolysis. Both extracellular and cell-associated autolysin activities of S. aureus were suppressed by dextran sulphate and high concentrations of heparin. The addition of hyaluronic acid enhanced autolysin activity. The release of lipoteichoic acid (LTA), a modulator of autolysin activity, from penicillin-treated bacteria was inhibited by heparin and dextran sulphate. However, hyaluronic acid had no effect on release of LTA. These results suggest that inhibition of penicillin-induced lysis of S. aureus by heparin results mainly from inhibition of LTA release while dextran sulphate inhibits both autolysin activity and LTA release. Hyaluronic acid appears to enhance penicillin-induced lysis through activation of the autolysins.

Bacteriolysis↗
PubMed1987

Extracellular products of Staphylococcus aureus reversibly inhibit the terminal differentiation of cultured mouse epidermal cells.

The effect of extracellular products from Staphylococcus aureus on the differentiation of mouse epidermal cells was studied using an in vitro cell culture system. The extracellular products from a clinical strain of S. aureus isolated from human skin lesions reversibly inhibited the Ca++-induced terminal differentiation of epidermal cells, as determined by their morphology and the extent of cornified envelope formation. This suggests that a similar modification of cell differentiation is involved in the pathogenesis of S. aureus-induced skin disease.

Animals↗
PubMed1986

Gangliosides in human and monkey lenses.

The amount of gangliosides was determined in normal human lens, cataractous human lens and normal monkey lens. The total gangliosidic sialic acids averaged 176.3 +/- 44.7 (SD) (n = 4) in normal human lenses, and 272.2 +/- 80.6 (n = 14) nmol per gram wet weight in cataractous lenses, respectively; the difference was statistically significant. In monkey lens, the content was 143.8 +/- 32.4 (n = 4) nmol per gram wet weight. The composition of the gangliosides was analyzed by high performance thin-layer chromatography: the components of the a-pathway biosynthesis comprised 78.3% and 70.2%, and those of the b-pathway 13.8% and 20.9%, in the normal and cataractous human lenses, respectively. In the monkey lens, the components of the a-pathway comprised 33.0% and those of the b-pathway were 56.6% of the total gangliosides. Increase in gangliosides was thought to be related with the mechanism underlying formation of cataract.

Animals↗
PubMed1985

[Morphological studies of human gallbladder].

I tried to make it clear three dimensional picture of the smooth muscle of the human gallbladder at first, and found a connection between the smooth muscle and the autonomic nerves in the wall. At autopsy the gallbladder without lesion was collected from 15 males and 7 females died of apoplexy, head injury or myocardial infarction. These material was fixed 10% neural formalin, impregnated into Masson Trichrome for smooth muscle, and modified Golgi method for nerve fivers, embeded in celloidin. I laid a picture after another after tracing serial tangential section of 8 micron by using camera lucida, and made three dimensional picture. In autonomic nerve in the wall three dimensional sections of 100-150 micron were made and observed with light microscope. Three dimensional muscle structure showed monounit structure, having meshwork structure from mucosal area to serous one. It was gratified the condition of the gallbladder contraction to illustrate a series of connection from mucosal aspect to serous one. Many fine nerve fivers were found forming plexuses in the subserous layer, muscular layer and mucosa. There was close relationship between smooth muscle and intramural nerve fibers, which especially distributed into meshwork structure of muscle. I could find morphological relation among the layers, such as three main plexuses. It was suggested that subserous plexus had extrinsic nature.

Adult↗