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S Shigeta

Publications and source records attributed to S Shigeta.

At least 289 records · Page 16Linked to original sources
PubMed1984

[Comparative studies of antimicrobial agents against causative organisms isolated from urinary tract infections (1982). I. Susceptibility distribution].

In vitro activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections were investigated by dilution method using MIC 2000 (Dynatec) during July to October in 1982. The summarized results are as follows: PMPC and CCL have showed potent activities against E coli among the oral antimicrobial agents. PMPC and CCL at 3.13 micrograms/ml inhibited 90% of E. coli tested. CTM, CTX, CZX, CMX and LMOX at concentrations of 0.39 microgram/ml or less among the parenteral antimicrobial agents inhibited 90% of E. coli tested. The value of MIC90 (concentration at which 90% of isolates are inhibited) against K. pneumoniae results in the resistant range for ABPC, NA, CEX, CCL and ST. Among the parenteral cephems, CMX seemed most effective against K. pneumoniae tested. C. freundii seemed generally low susceptible to antimicrobial agents tested. Among the oral agents, PMPC, PPA and ST have showed moderate activity against C. freundii. Among the parenteral agents, CMX and LMOX also showed moderate activity against C. freundii, inhibiting 50% of the strains tested at 6.25 micrograms/ml. Among the oral agents, PMPC showed the most potent activity against E. cloacae. E. cloacae tested were highly resistant to the first and second generation cephems. Among the third generation, CMX seemed the most potent activity against E. cloacae isolated. However, CMX concentration of 1.56 micrograms/ml was necessary to inhibit 50% of tested E. cloacae. P. mirabilis tested was resistant to all oral antimicrobial agents except CCL and ST. The value of MIC90 of the first and second generation cephems against P. mirabilis results in the moderately susceptible range (6.25-25 micrograms/ml). The third generation seemed most effective against P. mirabilis tested. PMPC, NA, PPA and ST concentrations of 0.78-1.56 micrograms/ml were necessary to inhibit 50% of tested P. vulgaris. CEZ and CTM, seemed less potent activity than CFX and CMZ against P. vulgaris. CTX, CZX, CMX and LMOX except CPZ have showed potent activities against P. vulgaris, these at 0.1 micrograms/ml or less inhibited 50% of P. vulgaris tested. P. aeruginosa has been resistant to the third generation cephems except CPZ, but TOB, GM, AMK, CFS, PIPC and CPZ have showed high activities against P. aeruginosa, inhibiting 50% of the strains tested at 0.39-6.25 micrograms/ml. The oral antimicrobial agents, and first and second generation cephems had not showed significant activity against S. marcescens. And strains of S. marcescens were relatively susceptible to the third generation cephems.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Bacterial Agents↗
PubMed1984

[Comparative studies of antimicrobial agents against causative organisms isolated from urinary tract infections (1982). III. Secular changes in susceptibility].

In vitro susceptibilities have been investigated against several species isolated from patients with simple and complicated urinary tract infections (UTI) during 1980-1982. Antimicrobial activities of the third generation cephems against E. coli isolated from patients with complicated UTI were found to decrease slightly in 1982. And those against Klebsiella spp. isolated from patients with simple and complicated UTI were also found to decrease similarly. Against P. mirabilis, all the drugs tested have showed relatively potent activities and slight changes in the susceptibility. The marked decrease of susceptibility against Citrobacter spp. isolated from UTI have been found even in the third generation cephems. Especially, Citrobacter spp. exhibited a greater degree of resistant to CZX and CPZ. Strains of P. aeruginosa were on the whole susceptible to the drugs tested, CFS, GM, TOB and AMK, inhibiting 50-80% of the strains tested at 1.56 micrograms/ml. CTX, CZX and CMX seemed most effective against S. marcescens among the third generation cephems, inhibiting 50-90% of the strains tested at 3.13 micrograms/ml.

Anti-Bacterial Agents↗
PubMed1984

[Comparative studies of antimicrobial agents against causative organisms isolated from urinary tract infections (1982). II. Background of patients].

The frequency of the causative strains in urinary tract infections was investigated from the point of view of the patient's background such as age, sex administration of antibiotics and so on. Especially, the frequency of the causative strains isolated from patients within 3 days after the administration of antibiotics has markedly decreased. However, the frequency of the resistant strains such as P. aeruginosa, Enterobacter spp., Citrobacter spp. and Serratia spp. has increased after 8 days' administration of antibiotics.

Adult↗
PubMed1983

Comparative efficacy of antiherpes drugs against various strains of varicella-zoster virus.

Twenty antiherpes compounds were compared for their inhibitory activities against five laboratory strains and five clinical isolates of varicella-zoster virus (VZV) in human embryo fibroblast cultures. E-5-(2-bromovinyl)-1-beta-D-arabinofuranosyluracil (BVaraU), E-5-(2-iodovinyl)-2'-deoxyuridine (IVDU), and E-5-(2-bromovinyl)-2'-deoxyuridine (BVDU) were the most effective. The average values of the 50% inhibitory dose (ID50) for VZV replication were 0.0013, 0.0015, and 0.0024 micrograms/ml, respectively. 1-beta-D-Arabinofuranosyladenine and 9-(2-hydroxyethoxymethyl)guanine were 1.2 and 3.4 times less effective than 5-iodo-2'-deoxyuridine (IDU). The selectivity indexes (ratio of ID50 for host-cell DNA synthesis to ID50 for VZV replication) of BVaraU, IVDU, and BVDU were between 41,000 and 67,000, whereas those of cytosine arabinoside, IDU, and 5-bromo-2'-deoxyuridine were less than 1.1. BVaraU, IVDU, and BVDU were the most potent and the most selective inhibitors of VZV activity. A deoxythymidine kinase deficient mutant of VZV was resistant to most of the compounds tested at concentrations up to 36,000 times greater than the average ID50 for strains that were not deficient.

Antiviral Agents↗
PubMed1983

Purification and characterization of an alpha-mannosidase of sea-squirt.

An alpha-mannosidase was isolated from the extract of acetone powder of CHCl3-treated internal organs of the sea-squirt, Styela plicata. The enzyme was purified 4,110-fold in 11% yield. The preparation was fairly homogeneous on disc and SDS-polyacrylamide gel electrophoreses and Sephadex G-200 chromatography. The enzyme had an estimated molecular weight of 275,000 by gel chromatography and 70,000 by SDS-polyacrylamide gel electrophoresis, and was therefore considered to be a tetramer. The optimum pH for the enzyme activity was 3.4 but the stable pH range was from 4 to 6. The isoelectric point was 5.0. The enzyme was activated by Zn2+ but inhibited by Cu2+, Fe2+, Hg2+, and EDTA. The isolated enzyme released mannose not only from stem bromelin glycopeptide and ovalbumin glycopeptide but also from yeast mannan.

Animals↗
PubMed1983

Incomplete growth of varicella-zoster virus in human monocytes.

Infection of human peripheral blood monocytes by varicella-zoster virus (VZV) was investigated. When freshly isolated monocytes of young adult volunteers were infected with cell-free VZV and examined by indirect immunofluorescence, specific antigens appeared at 8 hr and the number of antigen-positive cells reached the maximum between 24 and 48 hr postinfection. The proportion of antigen-positive cells to total cells was similar to that of the permissive control (HeLa cells), while very few infectious centers (IC) of monocytes were formed in comparison with the infected control cells. Monocytes isolated from infants and old persons formed a larger number of IC than those of young adults. Electron microscopic study of VZV-infected monocytes from three young adult volunteers demonstrated that the proportion of VZV particle-positive cells to total cells was similar to that of antigen-positive cells, and most of the particles seen in the nuclei were low in density and lacked a central core. These results suggest that the growth of VZV in human adult monocytes is incomplete. This restriction of VZV growth by monocytes may play an important role in defense against VZV infection.

Adult↗
PubMed1983

Serological classification of Achromobacter xylosoxidans.

Adult rabbits were immunized with nine Achromobacter xylosoxidans strains by intravenous injection of Formalin-killed organisms. Antisera thus obtained were reciprocally titrated with the nine A. xylosoxidans strains, and seven sera were defined as serologically distinct. Three of nine antisera possessed one common antibody while also each having their own specific antibody. Ninety-five strains of A. xylosoxidans were examined for serotyping by a microtiter agglutination test with the nine antisera, and the strains were divided into seven serogroups. The distribution of the 95 strains among the serogroups was as follows: serogroup A, 15 strains; B, 17 strains; C, 43 strains; D, 2 strains; E, 4 strains; G, 8 strains; F, 2 strains. Four strains were not agglutinated with any of the antisera. Serogroups A, B, and F had the ability to reduce nitrate to nitrogen gas and to grow in heart infusion broth at 41 degrees C, although there were some exceptions. In contrast, most strains of serogroups C, D, and E could not produce nitrogen gas from nitrate, although they did produce nitrite. The strains of serogroup C could not grow at 41 degrees C, whereas those of serogroups D and E could. Thus, we concluded that serogroups A, B, and F referred to biotype IIIb described by Tatum, and serogroups C, D, and E referred to biotype IIIa. The serotyping of A. xylosoxidans may be useful for the analysis of nosocomial infections caused by these organisms.

Agglutination Tests↗
PubMed1983

[Effects of alcohol drinking on mental task performance].

The effects of low level alcohol in man were studied by several psychophysiological tests. Five male college students were tested on the battery of mental tasks involving Dot-Matrix, Signal Sound Detection, Choiced Reaction Time at three levels (33.5, 67.0, 134.0 ml : whisky) of alcohol dose. Alcohol concentration in breath, critical flicker fusion, heart rate and blinking counts were measured. Results obtained are as follows. Increase in the alcohol concentrations in breath and heart rate, decrease in the blinking counts are shown in proportion to alcohol dose level. Alcohol effects of least dose (33.5 ml) in this experiment are shown clearly on the condition of adding two subsidiary tasks to the main task. The results of this study suggest that the complex-task-method is useful to estimate the effects of low level alcohol to the psychophysiological functions in man.

Adult↗
PubMed1983

[Comparison of antibacterial potencies of oral and parenteral antibiotic preparations against Escherichia coli, Klebsiella, Citrobacter, and Proteus isolated from urinary tract infections (3: 1981) 1. Susceptibility distribution].

In vitro activities of antibacterial agents against E. coli, Klebsiella, Citrobacter and Proteus which were isolated from patients with urinary tract infections at 8 hospitals in Japan, were investigated by dilution broth method using MIC 2000 (Dynatec) during July to October in 1981. The summarized results are as follows: Among oral antibacterial agents, MPC and PPA have showed potent antibacterial activities against E. coli and Klebsiella. In vitro activities of oral antibacterial agents against Proteus and Citrobacter showed not so potent. Among the first and second generation's parenteral antibacterial agents, CTM has showed potent antibacterial activities against E. coli and Klebsiella. Among the third generation's parenteral antibacterial agents, CMX, CTX and CZX have showed potent antibacterial activities against E. coli, Klebsiella, Proteus and Citrobacter.

Anti-Bacterial Agents↗
PubMed1983

[Comparison of antibacterial potencies of oral and parenteral antibiotic preparations against Escherichia coli, Klebsiella, Citrobacter, and Proteus isolated from urinary tract infections (3: 1981). 2. Changes in bacterial sensitivities].

Since 1979 the antibacterial activity of antibiotics against E. coli, Klebsiella, Citrobacter and Proteus isolated from patients with urinary tract infections has been investigated. The serious transition of susceptibilities of E. coli and Klebsiella could not be recognized in these antibiotics (MPC, ABPC, NA, PPA, CEX, CEZ, CTM, CMZ and CFX). However, a few resistant organisms against the third generation's antibiotics (CTX, CMX, CZX, LMOX and CPZ) have already been appeared, we have to observe these results, continuously.

Anti-Bacterial Agents↗
PubMed1983

[Comparison of antibacterial potencies of oral and parenteral antibiotic preparations against Escherichia coli, Klebsiella, Citrobacter, and Proteus isolated from urinary tract infections (3. 1981). 3. Patient backgrounds and bacterial sensitivities].

Routine susceptibilities testing of microorganisms isolated from patients are of restricted usefulness in the treatment of patients because of the delay in obtaining results. Thus, the empiric chemotherapy based on the susceptibility of microorganisms isolated from patients is necessary for the majority of patients with simple and complicated urinary tract infections. In this study the relation between changing susceptibility and background factors such as age, a sex distinction, antibiotics, areas in Japan, simple and complicated UTI and so on, has been investigated.

Adolescent↗
PubMed1982

Purification and characterization of a beta-N-acetylhexosaminidase of sea-squirt.

A beta-N-acetylhexosaminidase [EC 3.2.1.30] was isolated from internal organs of the sea-squirt, Styela plicata. The enzyme was purified 1,560-fold in 5% yield. The preparation was fairly homogeneous as examined by disc and SDS polyacrylamide gel electrophoresis and Sephadex G-200 chromatography. The molecular weight of the enzyme was estimated to be 132,000 by gel chromatography and 66,000 by SDS polyacrylamide gel electrophoresis. Therefore, this beta-N-acetylhexosaminidase was considered to be a dimer. The optimum pH for activity was 4.0 but the enzyme was stable in the pH range from 5 to 6. The isoelectric point was 4.99. This enzyme was inhibited by Fe2+, Hg2+, Ag+, and PCMB but not by acetate. The isolated enzyme hydrolyzed both p-nitrophenyl-N-acetyl-beta-D-glucosaminide and p-nitrophenyl-N-acetyl-beta-D-galactosaminide. The hydrolysis rate of p-nitrophenyl-N-acetyl-beta-D-galactosaminide was 43% of that of p-nitrophenyl-N-acetyl-beta-D-glucosaminide. The enzyme liberated N-acetylhexosamine from asialodegalactosyl ovomucoid glycopeptide, asialodegalactosyl fetuin glycopeptide and the fragment of hyaluronic acid prepared by hyaluronidase treatment.

Acetylglucosaminidase↗
PubMed1982

In vitro susceptibility of varicella-zoster virus to E-5-(2-bromovinyl)-2'-deoxyuridine and related compounds.

The in vitro susceptibility of eight strains of varicella-zoster virus (VZV) to E-5-(2-bromovinyl)-2'-deoxyuridine (BVDU) was examined in human embryonic fibroblasts by the following techniques: inhibition of focus formation by either cell-free VZV (4-day assay) or cell-associated VZV (2-day assay), inhibition of viral antigen formation (2-day assay), and inhibition of viral cytopathogenicity (15-day assay). The 50% inhibitory dose (ID50) of BVDU ranged from 0.001 microgram/ml (2-day assay) to 0.01 microgram/ml (15-day assay). BVDU appeared highly selective in its anti-VZV activity since even at concentrations as high as 100 micrograms/ml, BVDU did not markedly affect the viability of the host cells. The ID50 of BVDU for VZV was comparable to that of IVDU (E-5-(2-iodovinyl)-2'-deoxyuridine). Both drugs inhibited the replication of VZV at a much lower concentration than did other antiviral compounds such as iododeoxyuridine, ethyldeoxyuridine, arabinosylcytosine, arabinosyladenine, phosphonoacetic acid, iododeoxycytidine, and acycloguanosine. BVDU and IVDU were virtually inactive against a thymidine kinase-deficient VZV mutant, suggesting that phosphorylation by the viral enzyme is responsible, at least in part, for the selective anti-VZV activity of the compounds.

Antiviral Agents↗
PubMed1982

Experimental infection of immunocompromised mice with Achromobacter xylosoxidans.

The natural resistance of mice to Achromobacter (A.) xylosoxidans was decreased to 1/80 by a single dose of 250 mg of cylophosphamide (CY) per kg intraperitoneally. When mice were infected with 1 X 10(9) A. xylosoxidans, the numbers of organisms in the liver, spleen, kidneys, lungs and heart blood reached to more than 10(6) per g at 6 hr after infection, and then decreased to less than 10(4) at 96 hr after infection. However, in the CY-treated mice, the numbers of organisms in these organs began to increase rapidly at 6 hr after infection and exceeded 10(9) per g at 48 hr when the mice died. Seventeen of 18 immunocompromised mice and 23 of 24 normal mice which were infected with 1 to 2 X 10(9) organisms of A. xylosoxidans, respectively, were still living until 4 weeks after infection when they were killed and examined. Thirteen of the 33 surviving mice which were examined for bacteriological assay were chronically infected with A. xylosoxidans, some in the spleen, others in the kidney, lung, brain and/or heart blood but none were infected in the liver. Most of the infected and surviving mice had produced an antibody against A. xylosoxidans and its titer was higher in the bacteriologically "cured" group than in the chronically infected one. All surviving mice were resistant to the 2nd challenge with a lethal dose of A. xylosoxidans even when they received an effective dose of CY. The surviving mice showed activated cellular immunity and rather depressed humoral immunity as compared with normal mice or the mice which were infected with killed A. xylosoxidans.

Animals↗