Michiya Yokozaki

Emergence in Japan of an imipenem-susceptible, meropenem-resistant Klebsiella pneumoniae carrying blaIMP-6.

We identified 5 Klebsiella pneumoniae isolates showing high resistance to β-lactams except imipenem and designated them ISMRK (imipenem-susceptible but meropenem-resistant Klebsiella). They carried the bla(IMP-6) and bla(CTX-M-2) on a self-transmissible plasmid. ISMRK may be falsely categorized as susceptible to carbapenems if imipenem is used to screen carbapenem resistance.

Glutathione S-transferase-π gene expression and platinum drug exposure in human lung cancer

Abstract We examined the association between the gene expression levels of glutathione S -transferase-π (GST-π) and platinum drug exposure in human lung cancer. First we monitored GST-π gene expression levels in two lung cancer cell lines and in peripheral mononuclear cells of ten previously untreated lung cancer patients after platinum drug exposure. Next we examined GST-π gene expression levels in 40 lung cancer autopsy specimens. The GST-π gene expression levels were assessed by the quantitative reverse transcription–polymerase chain reaction or Northern blot analysis. The GST-π gene expression was not induced by platinum drugs either in vitro and in vivo within 24 h of exposure. In contrast, GST-π gene expression levels in lung cancer tissues of patients who had been exposed to platinum drugs at least 1 month before death were significantly higher than that in those of patients who had not been exposed. These results suggest that GST-π gene expression is associated with chronic exposure to platinum drugs in lung cancer and/or the stress response to xenobiotics.

Prevalence of Helicobacter pylori infection, endoscopic gastric findings and dyspeptic symptoms among a young Japanese population born in the 1970s

Background:  With the prevalence of Helicobacter pylori (H. pylori) infection rapidly decreasing in Japan, endoscopic findings and dyspeptic symptoms need to be re‐evaluated.

Gastric acidity in patients with follicular gastritis is significantly reduced, but can be normalized after eradication for Helicobacter pylori.

Background.  Follicular gastritis is thought to be caused by Helicobacter pylori infection. However, the pathophysiology of it remains unclear.

Complete Nucleotide Sequence of the IncN Plasmid Encoding IMP-6 and CTX-M-2 from Emerging Carbapenem-Resistant Enterobacteriaceae in Japan

ABSTRACT We have determined the DNA sequence of Klebsiella pneumoniae multidrug resistance plasmid pKPI-6, which is a self-transmissible IncN-type plasmid. pKPI-6 harboring blaIMP-6 and blaCTX-M-2 confers a stealth-type carbapenem resistance phenotype on members of the family Enterobacteriaceae that is not detectable with imipenem. pKPI-6 is already epidemic in Japan, favoring the dissemination of IMP-6 and CTX-M-2 in members of the family Enterobacteriaceae.

Imipenem-Susceptible, Meropenem-Resistant Klebsiella pneumoniae Producing OXA-181 in Japan

The incidence of infections by Enterobacteriaceae carrying the carbapenemase gene showing a paradoxical phenotype of resistance to virtually all s-lactams, including meropenem but not including imipenem, is increasing ([1][1], [2][2], [3][3]). Here we report the first isolation of Klebsiella

Meropenem Resistance in Imipenem-Susceptible Meropenem-Resistant Klebsiella pneumoniae Isolates Not Detected by Rapid Automated Testing Systems

ABSTRACT Klebsiella pneumoniae showing high resistance to all β-lactams except imipenem, designated as ISMRK (imipenem-susceptible meropenem-resistant Klebsiella) is emerging in Japan. The carbapenem resistance of ISMRK cannot be screened by the Vitek and the RAISUS rapid automated susceptibility test systems, which may lead to inappropriate antimicrobial therapy, resulting in compromised patient outcomes.

Rapid detection of blaIMP-6 by amplification refractory mutation system.

Klebsiella pneumoniae resistant to almost all ß-lactams except imipenem designated as ISMRK (imipenem-susceptible meropenem-resistant Klebsiella) is emerging in Japan. All ISMRK carries bla(IMP-6) which differs from bla(IMP-1) by only a single nucleotide at position 640. We devised a rapid detection system of bla(IMP-6) by using ARMS PCR.

Multiple Intraabdominal Abscesses Caused by Mycoplasma hominis Infection Following Simultaneous Pancreas-Kidney Transplantation

Yumiko Okumura, B.A., Toshiki Kajihara, M.D., Yumiko Koba, M.S., Makoto Onodera, B.A., Toshinori Hara, M.S., Hiroyuki Tahara, M.D., Hideki Ohdan, M.D., Hiroki Ohge, M.D., Michiya Yokozaki, M.D., and Motoyuki Sugai, D.D.S. Project Research Center for Nosocomial Infectious Diseases, Hiroshima University, Hiroshima, Japan; Division of Infectious Diseases Laboratory, Department of Clinical Practice and Support, Hiroshima University Hospital, Hiroshima, Japan; Division of Laboratory Medicine, Hiroshima University Hospital, Hiroshima, Japan; Department of Infectious Diseases, Hiroshima University Hospital, Hiroshima and Department of Gastroenterological and Transplant Surgery, Hiroshima University, Hiroshima, Japan

Two Cases of Clostridium tertium Infection and Successful Identification of the Organism by Matrix- Assisted Laser Desorption-Ionization Time-of-Flight Mass Spectrometry Analysis

Yumiko Joichi, A.D., Shizuo Kayama, D.D.S., Ikue Hayashi, Ph.D., Makoto Onodera, B.S.E., Maki Furushimo, A.D., Yumiko Koba, M.S., Michiya Yokozaki, M.D., Hiroki Ohge, M.D., and Motoyuki Sugai, D.D.S. Project Research Center for Nosocomial Infectious Diseases, Hiroshima University; Section of Infection Diseases, Laboratory Division of Clinical Support, Hiroshima University Hospital; Research Facility, Hiroshima University Faculty of Dentistry; Division of Laboratory Medicine, Hiroshima University Hospital; Department of Infectious Diseases, Hiroshima University Hospital, Hiroshima, Japan