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Y Obana

Publications and source records attributed to Y Obana.

At least 37 records · Page 2Linked to original sources
PubMed1991

Adherence of Serratia marcescens in the pathogenesis of urinary tract infections in diabetic mice.

The adherence of Serratia marcescens to bladder epithelial cells of mice with alloxan-induced diabetes was studied. S. marcescens adhered more strongly to the bladder epithelial cells of diabetic mice than to those of normal mice both in vitro and in vivo. The susceptibility of diabetic mice to urinary tract infection may be due to an increased adhesive capacity of bladder epithelial cells.

Animals↗
PubMed1991

Virulence of Escherichia coli strains with R-plasmid mediated penicillin resistance in mice infections.

Penicillinase I-, II- and III-producing R-plasmid of Escherichia coli were transferred to Escherichia coli 177, KC-14, and 444. These strains are highly virulent in mice. This study was conducted to investigate the influence of conjugative R-plasmid on the virulence of its host strains. Escherichia coli 177 after penicillinase I- or III-producing R-plasmids transfer retained parental levels of virulence. On the other hand, penicillinase II-producing transconjugants showed reduced virulence in mice. The virulence of its revertants, in which R-plasmid was eliminated by heat, were equivalent to that of the host strain. It is suggested that the decrease in the virulence of transconjugants was not due to transferred R-plasmid. The reduced virulence of the these transconjugants may be due to alterations in their components such as the lipopolysaccharides in the cell envelope.

Animals↗
PubMed1991

[The infectivity of Enterococcus faecalis in experimental urinary tract infection in mice: II].

The infectivity of Enterococcus faecalis was compared with that of Escherichia coli in the urinary tract in mice. The infectivity of E. faecalis in normal mice was found to be equal to that of E. coli. The mice previously treated with cyclophosphamide, carrageenin or alloxan as the immunosuppressive drug, and restricted water supply, were more susceptible to enterococcal infection than non-treated ones. These data were confirmed with histological examinations. E. faecalis is a pathogenic organism in the urinary tract and therefore cautions should be given to the treatment in clinical practice.

Animals↗
PubMed1991

[An autopsy case of neoplastic angioendotheliosis mainly affecting the lung and presenting with atypical cells in peripheral blood].

Neoplastic angioendotheliosis (NAE) is a rare condition characterized by proliferation of atypical cells in small vessels of various organs. In the past, atypical cells seen in this condition were considered to originate from vascular endothelial cells. However, recent immunohistochemical studies have established that the tumor cells in this condition mainly originate from B-lymphocytes. NAE is likely to affect the central nervous system and skin. Cases of NAE with a primary lesion in the pulmonary vessels are rare. One such rare case of NAE was recently encountered by us. The patient was a 77-year-old woman who was admitted to our department because of fever and interstitial shadow in both lungs. After admission, fever did not subside, and the pulmonary shadow became more marked. Laboratory tests upon admission disclosed elevated LDH. Of isozymes, LDH2 and LDH3 were high. Anemia and thrombocytopenia gradually became aggravated, and atypical cells with large basophilic cell body and irregularly shaped nucleus subsequently appeared in peripheral blood. Thereafter, the patient's general condition worsened rapidly and she died about 5 months after admission. Post-mortem examination revealed pleomorphic atypical cells filling the lumen of small vessels in various regions of the body. This finding was particularly marked in pulmonary vessels. With various immunohistochemical stains, these cells were identified as cells of B-lymphocyte origin.

Aged↗
PubMed1991

[Combination antibacterial effects between aztreonam and eight other antibiotics].

In vitro interactions between aztreonam (AZT) and 8 other antibiotics were studied using the agar dilution checkerboard technique against 88 clinical isolates of Escherichia coli, Proteus vulgaris, Serratia marcescens and Pseudomonas aeruginosa. Combinations of AZT with 8 other antibiotics were generally additive or indifferent. Synergism was occasionally seen against S. marcescens or P. aeruginosa with AZT plus isepamicin (ISP). Antagonism was observed only between AZT and latamoxef against P. vulgaris. In a phase-contrast microscopic study, synergistic effects between AZT and aspoxicillin or ISP were confirmed against E. coli 177 and P. aeruginosa 15846. AZT in combination with ISP demonstrated a synergy against experimental urinary tract infection in mice caused by P. aeruginosa 15846. We believe that combinations of several antibiotics with AZT should be considered for initial therapy of infections because synergism and additive action were observed and antagonism was rarely found in our study.

Amoxicillin↗
PubMed1991

[Humoral immunity and lymphocyte subsets in patients with dilated cardiomyopathy].

We examined immunological abnormalities in patients with dilated cardiomyopathy (DCM) and reviewed their medical histories, NYHA classifications, electrocardiogram findings and chest X-Ray findings with regard to severity of DCM. Elevated CD4/CD8 ratio as well as decreased number of CD8 cells in lymphocyte subsets was recognized. These abnormalities were particularly noted in patients with past history of myocarditis. NYHA IV class increases in CTR and left ventricular dimension, and a reduced ejection fraction. These findings suggest that lasting of myocardial damage causes immunological abnormalities and the examination of DCM patients' immunological status is useful in anticipating disease process and determining medical treatment.

Autoantibodies↗
PubMed1990

In-vitro and in-vivo activities of sulbactam and YTR830H against Acinetobacter calcoaceticus.

The antibacterial activities of sulbactam and YTR830H, both beta-lactamase inhibitors, were studied against Acinetobacter calcoaceticus, in vitro and in vivo. In-vitro susceptibility tests showed both to be very active against 80 clinical isolates of A. calcoaceticus. Against an intraperitioneal infection in mice, caused by A. calcoaceticus Ac54, the 50% effective doses of sulbactam and YTR830H were 1.62 and 16.7 mg/kg, respectively. Against A. calcoaceticus S31, a strain resistant to gentamicin, sulbactam and YTR830H were active both in vitro and in vivo.

Acinetobacter↗
PubMed1990

In-vitro and in-vivo antibacterial activities of E1040, a new cephalosporin with potent antipseudomonal activity.

E1040 is a new parenteral cephalosporin with a broad antibacterial spectrum and potent activity against Gram-negative bacteria including Pseudomonas aeruginosa. The in-vitro activities of E1040 against clinical isolates of Enterobacter cloacae, Ent. aerogenes, Providencia rettgeri, and Morganella morganii were superior to those of ceftazidime, cefoperazone, cefmenoxime, and cefuzonam. The activities of E1040 against Gram-positive cocci were comparable with those of ceftazidime, but it was less active than cefmenoxime, cefuzonam, and cefoperazone. Against Ps. aeruginosa, E1040 was more potent than the other compounds, with an MIC90 of 0.39 mg/l, 1/16 that of ceftazidime. The in-vitro activity of E1040 was well sustained in vivo as shown by results obtained in experimental infections in mice. In particular, E1040 was the most active drug against Ps. aeruginosa including gentamicin-resistant and beta-lactamase-overproducing strains. Morphological studies using a scanning electron microscope and a phase-contrast microscope showed that E1040 caused spheroplast and bulge formation in Ps. aeruginosa at low concentrations.

Animals↗
PubMed1990

[The virulence of Enterococcus faecalis in experimental urinary tract infection in mice].

The virulence of Enterococcus faecalis in the urinary tract in mice was studied. Pyelonephritis was distinctly caused by E. faecalis which have a high affinity to mouse kidneys. This infection was continuous, but did not turn into sepsis. The relationship between the production of hemolysin or protease and the virulence in the urinary tract was investigated without finding any distinct association. It is concluded that E. faecalis is a pathogenic organism in the urinary tract and presumably induces a severe infection in the compromised host.

Animals↗
PubMed1990

[Bacterial combination effect between carumonam and eight other antibiotics].

In vitro interactions between carumonam (CRMN) and 8 other antibiotics were studied using the agar dilution checkerboard technique against 88 clinical isolates of Escherichia coli, Proteus vulgaris, Serratia marcescens and Pseudomonas aeruginosa. Combinations of CRMN with 8 other antibiotics were generally additive or indifferent. Synergism was found against S. marcescens or P. aeruginosa with CRMN plus fosfomycin, gentamicin (GM) or dibekacin. Antagonism was not observed with CRMN plus any of the 8 other antibiotics tested. In a phase-contrast microscopic study, the synergism of CRMN in combination with GM were confirmed against P. aeruginosa 15846. CRMN in combination with GM demonstrated a in vivo synergy against experimental urinary tract infection caused by P. aeruginosa 15846 in mice. We think that combinations of several antibiotics with CRMN should be appropriate for initial therapy of infections because no antagonism appeared to occur with other antibiotic agents.

Animals↗
PubMed1989

The virulence of Enterobacter cloacae and Serratia marcescens in experimental bladder infection in diabetic mice.

Diabetic mice were significantly more susceptible than normal mice to bladder infection with Enterobacter cloacae or Serratia marcescens but not to intraperitoneal infection. Normal urine inhibited the growth of E. cloacae and S. marcescens, whereas urine from diabetic mice permitted multiplication. The addition of urea to urine from diabetic mice restored its antibacterial properties for E. cloacae and S. marcescens. We consider that the decreased urea content of the urine of diabetic mice was responsible for their increased susceptibility to bacterial infection of the bladder.

Animals↗
PubMed1989

[Effect of insulin on the incidence of experimental Serratia marcescens cystitis in diabetic mice--relationship between insulin therapy and urea nitrogen content].

The effect of insulin on the incidence of experimental Serratia marcescens cystitis in alloxan-induced diabetic mice was studied. The symptoms in diabetes were improved by injection of insulin (1 I.U./b.i.d.) for 3 days. Diabetic mice treated with insulin showed lower susceptibility to cystitis with S. marcescens than non-treated diabetic mice, but slightly higher than normal mice. It was, therefore, suggested that the insulin treatment was important for prevention of S. marcescens cystitis. The prevention of cystitis in insulin-treated diabetic mice was possibly due to the increase of urea nitrogen that inhibits the growth of S. marcescens in urine.

Animals↗
PubMed1989

[Studies on the biological activity of slime isolated from staphylococci].

The biological characteristic and activity of slime isolated from Staphylococcus aureus No. 71 and Staphylococcus epidermidis No. 2 was studied. The slime isolated from both strains had high contents of protein, RNA (orcinol reaction-positive substances) and sugar. The slime showed low toxic effect when it was injected intravenously and intraperitoneally into mice. It, however, exhibited potent cytotoxic effect against mouse neutrophils in both ex vivo and in vivo experiments. The enhancement of virulence of Escherichia coli by slime isolated from staphylococci was due to neutrophil-impairing effect. It is suggested that the slime isolated from S. aureus and S. epidermidis may act as an virulence factor.

Animals↗
PubMed1989

In vivo activity of ciprofloxacin, ofloxacin, norfloxacin and pipemidic acid against Escherichia coli infections in mice.

The therapeutic efficacy of four quinolones, i.e. ciprofloxacin, ofloxacin, norfloxacin and pipemidic acid, was investigated in experimental infections in mice caused by pipemidic acid-susceptible and -resistant E. coli. For intraperitoneal infections caused by E. coli strain 444 and 23, the efficacy of ciprofloxacin, ofloxacin and norfloxacin was superior to that of pipemidic acid. Furthermore, ciprofloxacin and ofloxacin had higher activity than norfloxacin and pipemidic acid in urinary tract and uterine infections. Serum and uterus levels of ciprofloxacin and ofloxacin in normal mice were higher and more durable than those of norfloxacin.

Animals↗
PubMed1988

In vitro and in vivo antibacterial activity of KY-109, a new orally active cephalosporin.

The in vitro and in vivo antimicrobial potencies of KY-109, a pro-drug of KY-087, were compared with those of amoxicillin, cephalexin (CEX), and cefaclor (CCL). The following results were obtained. KY-087, which is the active form of KY-109, had broad antimicrobial spectrum against Gram-positive and Gram-negative organisms, but showed low antimicrobial activity against Enterobacter sp., Serratia, and Pseudomonas sp. The antimicrobial activities of KY-087 against clinically isolated Gram-positive organisms were superior to those of CEX and CCL. The antimicrobial activities of KY-087 against Gram-negative organisms, such as Enterobacter sp., Serratia, and Pseudomonas sp., were less active. KY-087 showed dose-related bactericidal activity against Staphylococcus aureus and Escherichia coli. The therapeutic efficacy of KY-109 against experimental intraperitoneal infections caused by Gram-positive and Gram-negative organisms in mice was comparable to that of CEX but inferior to that of CCL. In experimental granuloma pouch models in rats and kidney infection in rabbits, therapeutic efficacy of KY-109 was either comparable or superior to that of CEX and CCL.

Administration, Oral↗
PubMed1988

Therapeutic efficacy of ofloxacin, ciprofloxacin and NY-198 in experimentally infected normal and alloxan-induced diabetic mice.

The therapeutic efficacy of ofloxacin, ciprofloxacin and NY-198 was compared in alloxan-induced diabetic mice with experimental respiratory and urinary tract infections. Respiratory infection due to Klebsiella pneumoniae DT-S was well controlled by treatment with all compounds tested both in normal and diabetic mice. Similar observations were made in a model of urinary tract infection due to Serratia marcescens T-55. There was no difference between normal and diabetic mice in therapeutic efficacy of these compounds. They appear to be highly active antibacterial drugs in vitro under conditions which stimulate normal and diabetic states. There was no difference between normal and diabetic mice in the serum, lung and kidney concentrations. These observations suggest that ofloxacin, ciprofloxacin and NY-198 may be effective drugs in the treatment of bacterial respiratory and urinary tract infections which may occur in diabetic conditions.

Animals↗