著者
Toyotaka SATO Shin-ichi YOKOTA Torahiko OKUBO Kanako ISHIHARA Hiroshi UENO Yasukazu MURAMATSU Nobuhiro FUJII Yutaka TAMURA
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.12-0186, (Released:2012-11-14)
被引用文献数
8 30

Fluoroquinolone resistance is mainly caused by mutations in quinolone resistance-determining regions of DNA gyrase and topoisomerase IV in Escherichia coli. The AcrAB-TolC efflux pump contributes to resistance against fluoroquinolone and other antimicrobials. In this study, we investigated a high-level mechanism of fluoroquinolone resistance in E. coli that was isolated from human clinical samples and canine fecal samples. E. coli strains with high levels of fluoroquinolone resistance have been found to be frequently resistant to cephalosporins. Strains with high-level fluoroquinolone resistance exhibited lower intracellular enrofloxacin (ENR) concentrations, higher expression of AcrA, and a greater reduction in the fluoroquinolone minimum inhibitory concentration for treatment with an efflux pump inhibitor. The frequency of strains with enhanced ENR resistance selection and the survival rate of E. coli in the presence of ENR in vitro were correlated well with AcrA protein expression levels in the parental strains. These results suggest that AcrAB-TolC efflux pump over-expression is related to high-level fluoroquinolone resistance and the selection of strains with enhanced fluoroquinolone resistance.
著者
Masaru USUI Yutaka TAMURA Tetsuo ASAI
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.84, no.9, pp.1292-1298, 2022 (Released:2022-09-12)
参考文献数
87
被引用文献数
3

The emergence and spread of antimicrobial-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs) are a global public health concern. ARB are transmitted directly or indirectly from animals to humans. The importance of environmental transmission of ARB and ARGs has recently been demonstrated, given the relationships between compost, livestock wastewater, insects, and wildlife. In addition, companion animals and their surrounding environments (veterinary hospitals and homes with companion animals) should be considered owing to their close relationship with humans. This review discusses the current status and future perspectives of ARB and ARGs in animal-breeding environments.
著者
Naofumi Seira Naoki Yanagisawa Akiko Suganami Takuya Honda Makiko Wasai John W. Regan Keijo Fukushima Naoto Yamaguchi Yutaka Tamura Takayoshi Arai Toshihiko Murayama Hiromichi Fujino
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.40, no.10, pp.1806-1812, 2017-10-01 (Released:2017-10-01)
参考文献数
31
被引用文献数
3

Increases in the expression of prostaglandin E2 (PGE2) are widely known to be involved in aberrant growth in the early stage of colon cancer development. We herein demonstrated that the novel indole compound MW-03 reduced PGE2-induced cAMP formation by catalization to an inactive metabolite by inducing 15-hydroxyprostaglandin dehydrogenase through the activation of peroxisome proliferator-activated receptor-γ. MW-03 also inhibited colon cancer cell growth by arresting the cell cycle at the S phase. Although the target of MW-03 for cell cycle inhibition has not yet been identified, these dual anti-cancer effects of MW-03 itself and/or its leading compound(s) on colon cancer cells may reduce colon cancer development and, thus, have potential as a novel treatment for the early stage of this disease.
著者
Kanako ISHIHARA Mieko SAITO Natsumi SHIMOKUBO Yasukazu MURAMATSU Shigeki MAETANI Yutaka TAMURA
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.14-0119, (Released:2014-10-05)
被引用文献数
1

Veterinary staff carrying methicillin-resistant Staphylococcus aureus (MRSA) can be a source of MRSA infection in animals. To identify risk factors of MRSA carriage among veterinary staff, MRSA carriage and epidemiological information (sex, career, contact with MRSA-identified animal patients and others) were analyzed from 96 veterinarians and 70 veterinary technicians working at 71 private veterinary clinics in Japan. Univariate analysis determined sex (percentage of MRSA carriage, male (29.2%) vs. female (10.0%); P=0.002) and career (veterinarians (22.9%) vs. veterinary technicians (10.0%); P=0.030) as risk factors. Multivariable analysis revealed that sex was independently associated with MRSA carriage (adjusted odds ratio, 3.717; 95% confidence interval, 1.555–8.889; P=0.003). Therefore, male veterinary staff had a higher risk of MRSA carriage than female staff.
著者
Masaru USUI Yutaka TAMURA Tetsuo ASAI
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.22-0253, (Released:2022-07-22)
被引用文献数
3

The emergence and spread of antimicrobial-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs) are a global public health concern. ARB are transmitted directly or indirectly from animals to humans. The importance of environmental transmission of ARB and ARGs has recently been demonstrated, given the relationships between compost, livestock wastewater, insects, and wildlife. In addition, companion animals and their surrounding environments (veterinary hospitals and homes with companion animals) should be considered owing to their close relationship with humans. This review discusses the current status and future perspectives of ARB and ARGs in animal-breeding environments.
著者
Masaru USUI Akari KAJINO Michiha KON Akira FUKUDA Tomomi SATO Takahiro SHIRAKAWA Michiko KAWANISHI Kazuki HARADA Chie NAKAJIMA Yasuhiko SUZUKI Yutaka TAMURA
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.19-0144, (Released:2019-05-02)
被引用文献数
3

The emergence and spread of aminoglycoside-resistant bacteria are a public health concern. The acquisition of the genes encoding 16S rRNA methylases, such as armA, rmtA, and rmtB, confers high-level resistance to aminoglycosides. However, the prevalence has not been well investigated in Japanese veterinary fields. To determine the prevalence of 16S rRNA methylases in animals, we detected 16S rRNA methylases genes in Gram-negative bacteria from animals. Here, we report the isolation of rmtB amd armA from two of the 446 Escherichia coli (0.5%) and one of the 103 Klebsiella spp. isolates (1.0%) from companion animals, respectively. However, none of the isolations were observed from 2445 E. coli isolates derived from livestock in Japan. The prevalence of 16S rRNA methylases in animals, especially in companion animals, should be carefully monitored in Japanese veterinary fields to avoid the spreading of the genes.
著者
Toyotaka SATO Shin-ichi YOKOTA Risa ICHIHASHI Tomoka MIYAUCHI Torahiko OKUBO Masaru USUI Nobuhiro FUJII Yutaka TAMURA
出版者
公益社団法人 日本獣医学会
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
pp.13-0144, (Released:2014-03-18)
被引用文献数
7

Understanding the prevalence of antimicrobial-resistance and the relationship between emergence of resistant bacteria and clinical treatment can facilitate design of effective treatment strategies. We here examined antimicrobial susceptibilities of Escherichia coli isolated from dogs admitted to a university hospital (University hospital) and companion animal clinics (Community clinics) in the same city, and investigated underlying multidrug-resistance mechanisms. The prevalence of E. coli with intermediate and resistant interpretations to ampicillin (AMP), enrofloxacin (ENR) and chloramphenicol (CHL) was higher in the University hospital than in the Community clinics cases. Use of antimicrobials, including fluoroquinolone, was also significantly higher in the University hospital than in the Community clinics cases. Upon isolation using ENR-supplemented agar plates, all ENR-resistant isolates had 3–4 nucleotide mutations that accompanied by amino acid substitutions in the quinolone-resistance-determining regions of gyrA, parC and parE, and 94.7% of all isolates derived from the University hospital showed AMP and/or CHL resistance, and possessed blaTEM and/or catA1. The average mRNA expression levels of acrA, acrB and tolC, and the prevalence of organic solvent tolerance, in isolates derived from ENR-supplemented agar plates were significantly higher in the University hospital than in the Community clinics isolates. Thus, E. coli derived from the University hospital cases more often showed concomitant decreased susceptibilities to aminopenicillins, fluoroquinolones, and CHL than did those derived from the Community clinics; this was related to an active AcrAB–TolC efflux pump, in addition to acquisition of specific resistance genes and genetic mutations.
著者
Toyotaka SATO Shin-ichi YOKOTA Torahiko OKUBO Kanako ISHIHARA Hiroshi UENO Yasukazu MURAMATSU Nobuhiro FUJII Yutaka TAMURA
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.75, no.4, pp.407-414, 2013 (Released:2013-05-02)
参考文献数
38
被引用文献数
17 30

Fluoroquinolone resistance is mainly caused by mutations in quinolone resistance-determining regions of DNA gyrase and topoisomerase IV in Escherichia coli. The AcrAB-TolC efflux pump contributes to resistance against fluoroquinolone and other antimicrobials. In this study, we investigated a high-level mechanism of fluoroquinolone resistance in E. coli that was isolated from human clinical samples and canine fecal samples. E. coli strains with high levels of fluoroquinolone resistance have been found to be frequently resistant to cephalosporins. Strains with high-level fluoroquinolone resistance exhibited lower intracellular enrofloxacin (ENR) concentrations, higher expression of AcrA, and a greater reduction in the fluoroquinolone minimum inhibitory concentration for treatment with an efflux pump inhibitor. The frequency of strains with enhanced ENR resistance selection and the survival rate of E. coli in the presence of ENR in vitro were correlated well with AcrA protein expression levels in the parental strains. These results suggest that AcrAB-TolC efflux pump over-expression is related to high-level fluoroquinolone resistance and the selection of strains with enhanced fluoroquinolone resistance.