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Eiko Yabuuchi

Publications and source records attributed to Eiko Yabuuchi.

9 recordsLinked to original sources

An epidemiological study of the susceptibility and frequency of multiple-drug-resistant strains of Pseudomonas aeruginosa isolated at medical institutes nationwide in Japan.

The susceptibility of 3233 strains of Pseudomonas aeruginosa, isolated primarily in 2001, as agents of infection at 37 medical institutes with various specialties in seven regions of Japan (ranging from Hokkaido to Kyushu/Okinawa), to 18 antipseudomonal agents known to be active against P. aeruginosa was evaluated, in accordance with the National Committee for Clinical Laboratory Standards (NCCLS) guidelines. Of the 18 antipseudomonal agents, including some combinations of beta-lactamase inhibitors and antibacterial agents, ciprofloxacin had the lowest minimum inhibitory concentration (MIC)(50) (0.25 microg/ml) against P. aeruginosa, followed by meropenem, with an MIC(50) of 0.5 microg/ml. The MIC(50) of 7 of the examined antibacterial agents (ceftazidime, cefozopran, imipenem, biapenem, gentamicin, tobramycin, and levofloxacin) was between 1 and 2 microg/ml. Among the antipseudomonal agents tested, tobramycin showed the lowest MIC(90) (2 microg/ml), which was not significantly different from its MIC(50) (1 microg/ml). The MIC(90) of the other antibacterial agents examined ranged from 8 to 64 microg/ml and more. The susceptibility of the 3233 strains to the 12 antibacterial agents covered by the NCCLS guidelines was determined according to the standard method of the NCCLS guidelines. The frequency of strains resistant to meropenem, gentamicin, or tobramycin was relatively low (7.5%-8.3%). The frequency of strains showing intermediate to severe resistance to tobramycin was particularly low (8.0%). The frequency of strains resistant to aztreonam, imipenem, or levofloxacin was 16.7%-19.0%, about twice as high as the frequency of strains resistant to tobramycin. The susceptibility pattern of the 3233 strains (isolated from seven regions of Japan) to five antibacterial agents (ceftazidime, piperacillin, imipenem, gentamicin, and ciprofloxacin) was evaluated in relation to the regions from which they were isolated. The MIC(50) values of these antibacterial agents did not differ significantly among the regions. However, the MIC(90) values of ceftazidime and gentamicin were higher for strains isolated from the Kansai region than for strains isolated from other regions. The MIC(90) of ciprofloxacin was higher for strains isolated from the Tohoku, Kansai, and Kyushu/Okinawa regions than for strains isolated from other regions. Of the 3233 strains, 89 were classified as multiple-drug-resistant (imipenem, gentamicin, and ciprofloxacin) strains. Of these 89 strains, 42 were isolated from urine, 17 from sputum or pharyngeal mucus, 13 from pus, 8 from blood, 1 from cerebrospinal fluid, and 8 from other specimens. The frequency of multiple-drug-resistant strains was higher among strains isolated from the Tohoku and Kansai regions than in strains isolated from other regions.

Cerebrospinal Fluid↗

[An outbreak of legionellosis in a new facility of hot spring bath in Hiuga City].

Following cerebrating ceremony in 20 June 2002, for the completion of Hiuga Sun-Park Hot Spring Bath "Ofunade-no-Yu" facilities, Miyazaki Prefecture, Kyushu Island, 200 neighbors were invited each day to experience bathing on 20 and 21 June. The Bath "Ofunade-no-Yu" officially opened on 1 July 2002. On 18 July, Hiuga Health Center was informed that 3 suspected Legionella pneumonia patients in a hospital and all of them have bathing history of "Ofunade-no-Yu". Health Center officers notified Hiuga City, the main proprietor of the Bath business, that on-site inspection on sanitary managements will be done next day and requested the City to keep the bath facilities as they are. On 19 July, Health Center officers collected bath water from seven places and recommended voluntary-closing of "Ofunade-no-Yu" business. Because of various reasons, Hiuga City did not accept the recommendation and continued business up to 23 July. Because Legionella pneumophila serogroup 1 strains from 4 patients' sputa and several bath water specimens were determined genetically similar by Pulsed Field Gel Electrophoresis of Sfi I-cut DNA. "Ofunede-no-Yu" was regarded as the source of infection of this outbreak. On 24 July, "Ofunade-no-Yu" accepted the Command to prohibit the business. Among 19,773 persons who took the bath during the period from 20 June to 23 July, 295 became ill, and 7 died. Among them, 34 were definitely diagnosed as Legionella pneumonia due to L. pneumophila SG 1, by either one or two tests of positive sputum culture, Legionella-specific urinary antigen, and significant rise of serum antibody titer against L. pneumophila SG 1. In addition to the 8 items shown by Miyazaki-Prefecture Investigation Committee as the cause of infection. Hiuga City Investigation Committee pointed out following 3 items: 1) Insufficient knowledge and understanding of stuffs on Legionella and legionellosis; 2) Residual water in tubing system after trial runs might lead multiplication of legionellae in it; and 3) Inadequate disinfection and washing for whole circulation system prior the experience bathing. The Hiuga City Committee directed 24 measures to improve the sanitary condition of the facility including following 5 items. 1) Fix the manual for maintenance and management of the bath. 2) Keep sufficient overflow of bath water. 3) Put disinfection of filters into practice. 4) Precise measurement and control of the residual chlorine concentration in bath water. 5) Replacement of filtrating material from crushed porous ceramic into natural sand.

Disease Outbreaks↗

Morphology of the type strain of Bacillus anthracis EY 3169T=ATCC 14578T grown either aerobically or anaerobically on agar plates--observation by light and laser microscopes.

Growth characteristics including cell-arrangement of the type strain of Bacillus anthracis EY 3169T=ATCC 14578T grown on agar plates in level 3 laboratory were observed by both light and laser microscopes. Small daughter colonies appeared on parent colonies grown on 5% sheep blood or chocolate agar plates after 12 days incubation at room temperature. Daughter colonies, stained by Wirtz-Conklin method, were composed with vegetative cells and spores. Growth of daughter colonies might be supported by the debris of cells in the parent colony. Colonies grown under anaerobic conditions were flat with smooth edges, and the cells neither formed chains of any length, nor produced any spores after 25 days incubation at room temperature. It was thought that spores of B. anthracis were produced at the terminal stage of individual cell life instead of under unfavorable conditions for the organism. Air is needed for spore formation and cell-chain formation. More nutrients, probably amino acids, are needed for anaerobic growth rather than aerobic.

Aerobiosis↗

Correction of the connecting vowel and gender of the specific epithet in the name Sphingomonas macrogoltabidus Takeuchi et al. 1993 to Sphingomonas macrogolitabida.

In accordance with the Bacteriological Code (1990 Revision), the connecting vowel and gender of the specific epithet macrogoltabidus in combination with the generic name Sphingomonas must be -i- and the ending must be changed to -a to agree with the gender of the generic name, respectively. Thus Sphingomonas macroboltabidus Takeuchi et al. 1993 should be Sphingomonas macrogolitabida corrig. Takeuchi et al. 1993.

Species Specificity↗

Bacillus dysentericus (sic) 1897 was the first taxonomic rather than Bacillus dysenteriae 1898.

The basonym of Shigella dysenteriae (Shiga 1898) Castellani and Chalmers 1919 was first and officially proposed in 1897 as Bacillus dysentericus (sic) in Saikingaku Zasshi, published in Japan. In accordance with Section 6 (Citation of Authors and Names) of the Bacteriological Code (1990 Revision), the year of the first proposal of Shigella dysenteriae has to be corrected from Bacillus dysenteriae 1898 to Bacillus dysentericus (sic) 1897.

Bacillus↗

Emendation of the genus Sphingomonas Yabuuchi et al. 1990 and junior objective synonymy of the species of three genera, Sphingobium, Novosphingobium and Sphingopyxis, in conjunction with Blastomonas ursincola.

The 16S rDNA sequence similarities between the type strains of Sphingomonas paucimobilis and 32 other Sphingomonas species range from 90.2 to 99.6%. It might be possible to divide the genus into several new genera according to a dendrogram drawn from 16S rDNA sequence similarity. However, the phenotypic and biochemical information needed to define clusters of strains representing distinct genera within this group of organisms was not previously available. Although the cellular lipids of type strains of all 28 Sphingomonas species tested contained glucuronosyl-(1 --> 1)-ceramide together with 2-hydroxymyristic acid, other molecular species of sphingoglycolipids were distributed randomly. Sphingomonas natatoria and Sphingomonas ursincola, bacteriochlorophyll a-containing, gram-negative facultative phototrophs, belong to the cluster of the genus Sphingomonas. Other phototrophic Porphyrobacter and Erythrobacter species in the Sphingomonadaceae were classified into a cluster different from the genus Sphingomonas, as reported previously. None of the physiological and biochemical characteristics considered, including cellular lipids and fatty acid composition, provided evidence for the division of the current genus Sphingomonas. It is therefore concluded that the genus Sphingomonas should remain undivided at this time. The species of three recently proposed genera, Sphingobium, Novosphingobium and Sphingopyxis, in conjunction with Blastobacter ursincola, are junior objective synonyms of species of the genus Sphingomonas.

Alphaproteobacteria↗

Sphingomonas melonis sp. nov., a novel pathogen that causes brown spots on yellow Spanish melon fruits.

A polyphasic taxonomic study was performed on the phytopathogenic bacterial strains DAPP-PG 224(T) and DAPP-PG 228, which cause brown spot on yellow Spanish melon (Cucumis melo var. inodorus) fruits. Based on the presence of glucuronosyl ceramide (SGL-1) in cellular lipids, the results of fatty acid analysis and 16S rDNA sequence comparison, the strains had been identified as belonging to the genus Sphingomonas and as phylogenetically related to Sphingomonas mali, Sphingomonas pruni and Sphingomonas asaccharolytica. The levels of 16S rDNA sequence similarity of these three species to strain DAPP-PG 224(T) were respectively 98.0, 98.0 and 97.4%. DNA-DNA hybridization experiments between strains pathogenic on melon fruit and S. mali, S. pruni and S. asaccharolytica revealed < or = 16% relatedness. Based on these results, the two isolates studied are regarded as independent from the type strains of the three species mentioned above. Sphingomonas strains from melon fruits are recognized as forming a genetically and phenotypically discrete species and to be differentiated by phenotypic characteristics from all 29 named species of the genus. Thus, the name Sphingomonas melonis sp. nov. is proposed for the isolates from diseased melon fruits. The type strain is DAPP-PG 224(T) (= LMG 19484(T) = DSM 14444(T)). The G+C content of DNA of the type strain is 65.0 mol%.

Cucumis melo↗