Biomedical subjects

Y Mizunoe

Publications and source records attributed to Y Mizunoe.

42 records · Page 3Linked to original sources

PubMed1988

Cloning and sequence of the gene encoding the major structural component of mannose-resistant fimbriae of Serratia marcescens.

Serratia marcescens US46, a human urinary tract isolate, exhibits mannose-resistant hemagglutination and agglutinates yeast cells, thereby indicating that it has two types of adhesins. We constructed a cosmid library for the DNA of this organism and isolated DNA clones carrying genes for mannose-sensitive (MS) and mannose-resistant (MR) fimbriae. On introduction of the cloned genes into Escherichia coli K-12, MS and MR fimbriae were formed. These fimbriae were functionally and morphologically indistinguishable from those of S. marcescens. Subcloning of these gene clusters revealed that the genes encoding MS fimbriae reside on a 9-kilobase (kb) DNA fragment, while those encoding MR fimbriae are present on a 12-kb fragment. Transposon insertion and maxicell analyses revealed that formation of MR fimbriae is controlled by several genes which reside on the 9-kb fragment. The nucleotide sequence of smfA, the gene encoding the major structural component of MR fimbriae, revealed that this gene encodes a 174-amino-acid polypeptide with a typical procaryotic signal peptide. The primary structure of the smfA product showed significant homology with the primary structure of the E. coli fimbrial subunit.

Amino Acid Sequence↗

PubMed1983

[Comparative double-blind study of cefroxadine and cephalexin in the treatment of complicated urinary tract infection].

To evaluate the efficacy, safety, and utility of cefroxadine (CXD) for the treatment of complicated urinary tract infections, a double blind study comparing CXD with cephalexin (CEX) was carried out. Patient received either 1,500 mg/day of CXD 3 times a day, or 2,000 mg/day of CEX 4 times a day for 5 days by oral route, and the following results were obtained. Of the 305 patients, clinical efficacies were evaluated in 220 cases (CXD 105 cases, CEX 115 cases) except that excluded or dropped out. Side effect was evaluated in 301 cases (CXD 150 cases, CEX 151 cases). There was no statistically significant difference in the back ground characteristics between the 2 groups. Overall clinical assessment by the committee according to the "Criteria for Evaluation of Clinical Efficacy of Antimicrobial Agents on Urinary Tract Infection" patients evaluated as better than "good" were 64 of 105 (61.0%) for CXD and 75 of 115 (65.2%) for CEX. The difference between the 2 groups was not statistically significant. In effect on pyuria, patients evaluated as better than "decreased" were 58 of 105 (55.2%) for CXD and 69 of 115 (60.0%) for CEX. The difference between the 2 groups was not statistically significant. In effect of bacteriuria, patients evaluated as better than "decreased" were 57 of 105 (54.3%) for CXD and 69 of 115 (60.0%) for CEX. The difference between the 2 groups was not statistically significant. Analyses were stratified according to classification by the type of infection, diagnosis, degree of pyuria before treatment, and bacterial count before treatment. There were no statistically significant differences between the 2 treatment groups as to any item. In evaluation by attending physician, patients evaluated as better than "good" were 81 of 140 (57.9%) for CXD, and 85 of 141 (60.3%) for CEX. Statistically significant difference was not observed between the 2 groups. In drug usefulness by attending physician, patients evaluated as better than "usefulness" were 106 of 140 (75.7%) for CXD, and 109 of 141 (77.3%) for CEX. The difference between the 2 groups was not statistically significant. In evaluation of the infections with sensitive species to both CXD and CEX by the committee according to "Criteria for Evaluation of Clinical Efficacy of Antimicrobial Agents on Urinary Tract Infections, overall clinical efficacies were evaluated in 102 (CXD 48 cases, CEX 54 cases) which were infected with sensitive species. There was no statistically significant difference in the back ground characteristics between the 2 treatment groups.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMedDate not supplied

Preventive effect of dapsone on renal scarring following mannose-sensitive piliated bacterial infection.

Renal scarring has been thought to occur in the later stages of chronic pyelonephritis. We previously reported that mannose-sensitive (MS) piliated bacteria promoted renal scarring, which was prevented by antioxidants. The preventive effect of diaphenylsulfone (dapsone), which has a scavenging activity on active oxygen species, on renal scarring was examined. Female Sprague-Dawley rats were inoculated with clinical isolates of Serratia marcescens which had both MS and mannose-resistant pili or with recombinant strains which had MS pili on their surface; they were then administered 20 mg/kg of dapsone or not. Dapsone significantly suppressed scarring following infection of the kidney. The bacterial counts in the kidneys were not different in dapsone-treated and nontreated rats. We conclude that dapsone is effective in preventing renal scarring, and it is suggested that the clinical use of this drug may prevent renal scar formation following pyelonephritis.

Animals↗

PubMedDate not supplied

Effect of ebselen on renal scarring in rats following renal infection.

Renal scarring, which occurs following refluxing pyelonephritis, is considered to be involved in the development of reflux nephropathy. Prevention of renal scar formation requires immediate initiation of antimicrobial treatment; treatment delay results in renal scarring. We demonstrate that Ebselen, an antioxidant agent, given at a dose of 15 mg/kg twice a day prevents renal scarring in rats following direct renal parenchymal bacterial inoculation. In addition, using an ascending pyelonephritis model, which clinically resembles refluxing pyelonephritis in humans, we show that when initiation of antimicrobial treatment was delayed, coadministration of Ebselen prevents renal scar formation. These results show that Ebselen is effective in preventing renal scarring and suggest that the clinical use of this drug may prevent renal scar formation following pyelonephritis and progression to reflux nephropathy.

Animals↗

PubMedDate not supplied

Fleroxacin enhancement of superoxide production by polymorphonuclear leukocytes: the role of protein kinases.

New quinolone (NQ) antimicrobials may influence the functions of polymorphonuclear leukocyes (PMNs). Fleroxacin (FLRX), one of the newer NQs which has a long half-life in blood and a strong bactericidal effect, was examined for its influence on superoxide production by PMNs. Augmentation of superoxide production by PMNs when stimulated with phorbol myristate acetate (PMA) and formyl-methionyl-leucyl-phenylalanine (fMLP) was observed following the addition of 25, 50, 100 and 200 micrograms/ml of FLRX. In addition, the effects of staurosporine and H-7, inhibitors of protein kinase C (PKC), and of genistein, a tyrosine kinase (TK) inhibitor, on FLRX-enhanced superoxide production were examined. Superoxide production augmented by FLRX was diminished by the addition of staurosporine and H-7, when PMNs were stimulated with PMA, and by the addition of genistein, when PMNs were stimulated with fMLP. These results suggest that FLRX augments superoxide production by PMNs through enhancing the activities of phosphorylation by PKC or TK within the signal transduction pathway in PMNs.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

PubMedDate not supplied

Distribution of a methicillin-resistance gene in urinary isolates of methicillin-resistant staphylococci examined by enzymatic detection of the polymerase chain reaction.

We tried to examine the susceptibility to various antimicrobial agents and to detect the mec A gene using enzymatic detection of the polymerase chain reaction in methicillin-resistant Staphylococcus aureus (MRSA), methicillin-sensitive Staphylococcus aureus (MSSA) and Staphylococcus epidermidis isolated from patients with complicated urinary tract infections (UTIs). All the strains of MRSA and MSSA showed a low sensitivity to imipenem (IPM), ceftazidime (CAZ), flomoxef (FMOX), amikacin (AMK), ciprofloxacin (CPFX) and ofloxacin (OFLX). Although all the strains of MRSA had the mec A gene, none of the MSSA strains had it. 74% of S. epidermidis had the mec A gene and strains resistant to methicillin were seen in 72% of them. The mec A-positive S. epidermidis showed a lower susceptibility to IPM, CAZ, FMOX, AMK, CPFX and OFLX than the mec A-negative strains. These results suggest that methicillin resistance was due to the mec A gene in MRSA and methicillin-resistant S. epidermidis (MRSE), and that MRSEs were very common among the bacteria causing complicated UTI. When we try to control nosocomial infections due to MRSA, it should also be noted that MRSE can be a reservoir of the mec A gene.

Genes, Bacterial↗