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Dive into the research topics where Akihiko Kawana is active.

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Featured researches published by Akihiko Kawana.


Journal of Infection and Chemotherapy | 2009

Nationwide surveillance of bacterial respiratory pathogens conducted by the Japanese Society of Chemotherapy in 2007: general view of the pathogens' antibacterial susceptibility.

Yoshihito Niki; Hideaki Hanaki; Takemasa Matsumoto; Morimasa Yagisawa; Shigeru Kohno; Nobuki Aoki; Ayumi Watanabe; Junko Sato; R. Hattori; M. Terada; N. Koashi; T. Kozuki; A. Maruo; K. Morita; Kazuhiko Ogasawara; Y. Takahashi; J. Watanabe; K. Takeuchi; S. Fujimura; H. Takeda; H. Ikeda; N. Sato; K. Niitsuma; Mitsumasa Saito; S. Koshiba; M. Kaneko; Makoto Miki; Susumu Nakanowatari; Y. Honda; J. Chiba

For the purpose of nationwide surveillance of the antimicrobial susceptibility of bacterial respiratory pathogens collected from patients in Japan, the Japanese Society of Chemotherapy conducted a third year of nationwide surveillance during the period from January to April 2008. A total of 1,097 strains were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections. Susceptibility testing was evaluable with 987 strains (189 Staphylococcus aureus, 211 Streptococcus pneumoniae, 6 Streptococcus pyogenes, 187 Haemophilus influenzae, 106 Moraxella catarrhalis, 126 Klebsiella pneumoniae, and 162 Pseudomonas aeruginosa). A total of 44 antibacterial agents, including 26 β-lactams (four penicillins, three penicillins in combination with β-lactamase inhibitors, four oral cephems, eight parenteral cephems, one monobactam, five carbapenems, and one penem), three aminoglycosides, four macrolides (including a ketolide), one lincosamide, one tetracycline, two glycopeptides, six fluoroquinolones, and one oxazolidinone were used for the study. Analysis was conducted at the central reference laboratory according to the method recommended by the Clinical and Laboratory Standard Institute (CLSI). The incidence of methicillin-resistant S. aureus (MRSA) was as high as 59.8%, and those of penicillin-intermediate and penicillin-resistant S. pneumoniae (PISP and PRSP) were 35.5 and 11.8%, respectively. Among H. influenzae, 13.9% of them were found to be β-lactamase-non-producing ampicillin (ABPC)-intermediately resistant (BLNAI), 26.7% to be β-lactamase-non-producing ABPC-resistant (BLNAR), and 5.3% to be β-lactamase-producing ABPC-resistant (BLPAR) strains. A high frequency (76.5%) of β-lactamase-producing strains was suspected in Moraxella catarrhalis isolates. Four (3.2%) extended-spectrum β-lactamase-producing K. pneumoniae were found among 126 strains. Four isolates (2.5%) of P.aeruginosa were found to be metallo β-lactamase-producing strains, including three (1.9%) suspected multidrug-resistant strains showing resistance to imipenem, amikacin, and ciprofloxacin. Continual national surveillance of the antimicrobial susceptibility of respiratory pathogens is crucial in order to monitor changing patterns of susceptibility and to be able to update treatment recommendations on a regular basis.


Emerging Infectious Diseases | 2009

Human Infection with Highly Pathogenic Avian Influenza Virus (H5N1) in Northern Vietnam, 2004–2005

Nguyen Duc Hien; Nguyen Hong Ha; Nguyen Tuong Van; Nguyen Minh Ha; Trinh Thi Minh Lien; Nguyen Quoc Thai; Van Dinh Trang; Takuro Shimbo; Yoshimitsu Takahashi; Yasuyuki Kato; Akihiko Kawana; Samu Akita; Koichiro Kudo

Treatment with oseltamivir or methylprednisolone was not effective, and 7 of 29 patients died.


Journal of Infection and Chemotherapy | 2008

The first nationwide surveillance of bacterial respiratory pathogens conducted by the Japanese Society of Chemotherapy. Part 1: a general view of antibacterial susceptibility

Yoshihito Niki; Hideaki Hanaki; Morimasa Yagisawa; Shigeru Kohno; Nobuki Aoki; Ayumi Watanabe; Junko Sato; R. Hattori; N. Koashi; T. Kozuki; A. Maruo; K. Morita; Kazuhiko Ogasawara; Y. Takahashi; J. Watanabe; K. Takeuchi; Masashi Takahashi; H. Takeda; H. Ikeda; Hiroyasu Kaneda; K. Niitsuma; Mitsumasa Saito; S. Koshiba; M. Kaneko; S. Itabashi; Makoto Miki; Susumu Nakanowatari; Y. Honda; J. Chiba; Hiroshi Takahashi

The Japanese Society of Chemotherapy (JSC) conducted the first nationwide surveillance of bacterial respiratory pathogens during the period from January to August 2006. With the cooperation of 32 medical institutions throughout Japan, a total of 924 strains belonging to seven clinically relevant bacterial species were collected from adult patients with well-diagnosed respiratory tract infections (RTIs). Antimicrobial susceptibility testing of the 887 evaluable strains (205 Staphylococcus aureus, 200 Streptococcus pneumoniae, 9 Streptococcus pyogenes, 165 Haemophilus influenzae, 91 Moraxella catarrhalis, 74 Klebsiella pneumoniae, and 143 Pseudomonas aeruginosa) to 42 antibacterial agents was conducted at the Central Laboratory of the Research Center for Anti-infective Drugs of the Kitasato Institute, according to recommendations issued by the Clinical and Laboratory Standards Institute (CLSI). The antibacterial agents employed were 25 β-lactams, three aminoglycosides, four macrolides (including one azalide and one ketolide), one lincosamide, one tetracycline, two glycopeptides, five fluoroquinolones, and one oxazolidinone. The incidence of methicillin-resistant S. aureus (MRSA) was 63.4%, and the incidences of penicillin-intermediately resistant S. pneumoniae (PISP) and penicillin-resistant S. pneumoniae (PRSP) were 35.0% and 4.0%, respectively. Among H. influenzae, 21.2% of the strains were found to be β-lactamase-nonproducing ampicillin (ABPC)-intermediately resistant (BLNAI), 29.1% to be β-lactamase-nonproducing ABPC-resistant (BLNAR), and 4.8% to be β-lactamaseproducing ABPC-resistant (BLPAR) strains. The incidence of extended-spectrum β-lactamase-producing K. pneumoniae was 2.7% (2 of 74 strains). Three (2.1%) of the 143 P. aeruginosa strains were found to be metallo-β-lactamaseproducing, including 1 (0.7%) multidrug-resistant strain. Through the nationwide surveillance, we obtained fundamental antimicrobial susceptibility data of clinically relevant bacterial pathogens in adult RTI to various antibacterial agents. These data will be a useful reference for future periodic surveillance studies, as well as for investigations to control antimicrobial-resistant pathogens.


Emerging Infectious Diseases | 2014

Mother-to-Child Transmission of Congenital Chagas Disease, Japan

Kazuo Imai; Takuya Maeda; Yusuke Sayama; Kei Mikita; Yuji Fujikura; Kazuhisa Misawa; Morichika Nagumo; Osamu Iwata; Takeshi Ono; Ichiro Kurane; Yasushi Miyahira; Akihiko Kawana; Sachio Miura

We report a patient with congenital Chagas disease in Japan. This report reemphasizes the role of neglected and emerging tropical diseases in the era of globalization. It also indicates the need for increased vigilance for detecting Chagas disease in non–disease-endemic countries.


Diagnostic Microbiology and Infectious Disease | 2013

The utility of cerebrospinal fluid for the molecular diagnosis of toxoplasmic encephalitis

Kei Mikita; Takuya Maeda; Takeshi Ono; Yasushi Miyahira; Takashi Asai; Akihiko Kawana

The aim of this study was to assess the efficacy of nested polymerase chain reaction (PCR) and the loop-mediated isothermal amplification (LAMP) assay, which were developed to detect and identify toxoplasma parasites in human cerebrospinal fluid (CSF). Nested PCR was performed using primers generated by Dr. L.D. Sibley to target the 18S rDNA instead of the conventionally used primers which target the B1 gene. We also designed Toxoplasma gondii-specific LAMP primers targeting both genes. In vitro detection sensitivity was evaluated using 10-fold serially diluted genomic DNA purified from RH tachyzoites, and clinical sensitivity and specificity were evaluated using clinical CSF samples from 16 patients with toxoplasmic encephalitis (TE) and from 12 patients with other diseases. The 18S rDNA nested PCR showed the highest detection sensitivity limit with a minimum of 1.0 × 10(-8) ng/μL. However, sensitivity and specificity of nested PCR with clinical specimens were 50% and 100%, respectively. The sensitivity of molecular diagnosis of TE is not sufficient; therefore, patients clinically suspected of having TE should be treated promptly. Our molecular diagnostic tool would restrictively facilitate a definitive diagnosis of TE at an early stage in approximately 50% of patients.


Emerging Infectious Diseases | 2007

Spanish Influenza in Japanese Armed Forces, 1918–1920

Akihiko Kawana; Go Naka; Yuji Fujikura; Yasuyuki Kato; Yasutaka Mizuno; Tatsuya Kondo; Koichiro Kudo

Medical records of Japanese army hospitals show high death rates during the first influenza pandemic.


Parasitology International | 2014

The Direct Boil-LAMP method: A simple and rapid diagnostic method for cutaneous leishmaniasis

Kei Mikita; Takuya Maeda; Sachio Yoshikawa; Takeshi Ono; Yasushi Miyahira; Akihiko Kawana

Needle biopsy is widely used for the diagnosis of cutaneous leishmaniasis (CL) to obtain specimens for histology and culture. However, the use of such invasive procedures causes discomfort, requires technical expertise, and carries risks of bleeding and iatrogenic infection. Therefore, developing substitutive non-invasive diagnostic tools for CL will help reduce the risk of secondary infection and the exposure of both infected individuals and medical professionals. Here we employed loop-mediated isothermal amplification and boiled swab samples (Direct Boil-LAMP method) from CL model mice to develop a simple and rapid diagnostic method for CL. The detection limit of this procedure was 1.0×10(3)parasites/mL. Accordingly, this substitutive diagnostic method should prove useful for mass screening. In addition, we discuss the potential advantages of using it, particularly in endemic regions where medical resources are limited.


Influenza and Other Respiratory Viruses | 2010

An epidemiological analysis of severe cases of the influenza A (H1N1) 2009 virus infection in Japan

Koji Wada; Hiroshi Nishiura; Akihiko Kawana

Please cite this paper as: Wada et al. (2010). An epidemiological analysis of severe cases of the influenza A (H1N1) 2009 virus infection in Japan. Influenza and Other Respiratory Viruses 4(4), 179–186.


Parasitology International | 2015

Chronic Chagas disease with advanced cardiac complications in Japan: Case report and literature review

Kazuo Imai; Takuya Maeda; Yusuke Sayama; Morichika Osa; Kei Mikita; Ichiro Kurane; Yasushi Miyahira; Akihiko Kawana; Sachio Miura

Due to the unprecedented recent increases in global migration, Chagas disease has become a global health threat and its epidemiology has drastically changed. Here we describe the first case in Japan of benznidazole treatment for chronic Chagas disease characterized by advanced cardiac complications. A 55-year-old Japanese-Brazilian woman who had previously presented with chronic heart failure was diagnosed as having Chagas disease and treated with benznidazole to prevent aggravation of her cardiac complications. However, benznidazole administration was stopped on day 56 due to severe drug-induced peripheral neuritis. Sixteen months later, her serologic test for Trypanosoma cruzi is still positive and she is being followed regularly by cardiology. Despite an estimated prevalence of over 4000 cases in Japan, only a few cases of Chagas disease have been reported. A Medline search revealed only 7 cases identified between 1995 and 2014 in Japan: in 6 cases, complications of chronic Chagas disease were apparent at the time of presentation, and sudden death occurred in 2 of these cases due to cardiac complications. This clinical case and literature review re-emphasize the urgent need to establish a surveillance network and improve the diagnostic methods and treatment framework for Chagas disease in Japan.


PLOS ONE | 2015

A Simple and Rapid Identification Method for Mycobacterium bovis BCG with Loop-Mediated Isothermal Amplification

Yuji Kouzaki; Takuya Maeda; Hiroaki Sasaki; Shinsuke Tamura; Takaaki Hamamoto; Atsushi Yuki; Akinori Sato; Yasushi Miyahira; Akihiko Kawana

Bacillus Calmette-Guérin (BCG) is widely used as a live attenuated vaccine against Mycobacterium tuberculosis and is an agent for standard prophylaxis against the recurrence of bladder cancer. Unfortunately, it can cause severe infectious diseases, especially in immunocompromised patients, and the ability to immediately distinguish BCG from other M. tuberculosis complexes is therefore important. In this study, we developed a simple and easy-to-perform identification procedure using loop-mediated amplification (LAMP) to detect deletions within the region of difference, which is deleted specifically in all M. bovis BCG strains. Reactions were performed at 64°C for 30 min and successful targeted gene amplifications were detected by real-time turbidity using a turbidimeter and visual inspection of color change. The assay had an equivalent detection limit of 1.0 pg of genomic DNA using a turbidimeter whereas it was 10 pg with visual inspection, and it showed specificity against 49 strains of 44 pathogens, including M. tuberculosis complex. The expected LAMP products were confirmed through identical melting curves in real-time LAMP procedures. We employed the Procedure for Ultra Rapid Extraction (PURE) kit to isolate mycobacterial DNA and found that the highest sensitivity limit with a minimum total cell count of mycobacterium (including DNA purification with PURE) was up to 1 × 103 cells/reaction, based on color changes under natural light with FDA reagents. The detection limit of this procedure when applied to artificial serum, urine, cerebrospinal fluid, and bronchoalveolar lavage fluid samples was also about 1 × 103 cells/reaction. Therefore, this substitute method using conventional culture or clinical specimens followed by LAMP combined with PURE could be a powerful tool to enable the rapid identification of M. bovis BCG as point-of-care testing. It is suitable for practical use not only in resource-limited situations, but also in any clinical situation involving immunocompromised patients because of its convenience, rapidity, and cost effectiveness.

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Yuji Fujikura

National Defense Medical College

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Takuya Maeda

National Defense Medical College

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Soichiro Kanoh

National Defense Medical College

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Kei Mikita

National Defense Medical College

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Yu Hara

National Defense Medical College

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Masaharu Shinkai

Yokohama City University Medical Center

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Yuji Kouzaki

National Defense Medical College

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Kazuo Imai

National Defense Medical College

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