Publications by authors named "Ohkusu M"

Non-typhoid Salmonella (NTS) includes many serotypes that differ in host, geographic distribution, and virulence. We report the case of a 64-year-old man who developed enteritis caused by Salmonella Kedougou without bacteremia after returning from Thailand. The patient stayed in Chiang Mai, Thailand, for 10 days to play golf and was hospitalized with fever, chills, watery diarrhea, and vomiting on the day the patient returned to Japan.

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Article Synopsis
  • Polymerase chain reaction-based open reading frame typing (POT) was used to study MRSA strains from neonatal intensive care units, focusing on their relationship with nosocomial infections and specific genes.
  • In total, 44 MRSA strains were analyzed, revealing 14 different POT types, with 28 strains identified as nosocomial infections and 11 strains carrying toxin-producing genes.
  • The study concluded that while certain POT types are associated with nosocomial infections, there wasn't a clear link between the presence of toxin-producing genes or antiseptic resistance and these infections, suggesting other factors may play a role.
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Objectives: In Japan, population-based epidemiological data on respiratory syncytial virus (RSV) infections are limited. To elucidate the epidemiology of RSV before the introduction of new prophylactic drugs, we conducted a population-based study during and after the SARS-CoV-2 pandemic.

Methods: This study was performed in four hospitals in Chiba City and three hospitals in Ichihara City.

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Article Synopsis
  • Understanding the in-vivo dynamics of pneumococci is crucial for investigating carriage in patients with invasive pneumococcal disease (IPD).
  • This study compared genomic and morphological differences between a capsular strain from blood and a non-capsular strain from sputum in a patient with IPD.
  • Findings indicated the blood strain was encapsulated while the sputum strain was non-encapsulated with a higher biofilm-forming capacity, suggesting a potential morphological change in Streptococcus pneumoniae during infection.
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Salmonella enterica subspecies enterica serovar Choleraesuis (S. Choleraesuis) is a nontyphoidal Salmonella pathogen that causes swine paratyphoids. S.

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We characterized serotype 24F sequence type (ST) 162 isolated from Japanese children with invasive pneumococcal disease (IPD). Owing to its highly invasive nature, serotype 24F is expected to be isolated from clinically significant cases. Serotype 24F ST162 isolates tested in the present study did not grow at 35°C in ambient air.

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Background: Infective endocarditis resulting from community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is a rare, but often fatal heart disorder. Here, we report a case of multidisciplinary treatment for infective endocarditis with systemic multiple abscesses due to Panton-Valentine leukocidin (PVL) producing CA-MRSA and Candida albicans .

Case Presentation: The patient suffered from infective endocarditis, destructive thyroiditis, hemorrhagic cerebral infarction due to mycotic embolism, lung abscess, multiple skeletal muscle abscess, and disseminate intravascular coagulopathy.

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After introducing the 13-valent pneumococcal conjugate vaccine (PCV13) for children, a change in the prevalence of different serotypes that cause invasive pneumococcal diseases (IPDs) has been observed. The prevalence of vaccine serotypes has decreased and that of non-vaccine serotypes has increased. Currently, serogroup 24 has become one of the major non-vaccine serotypes causing IPDs in children in Japan.

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Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections have increased worldwide in people without underlying diseases. CA-MRSA can often cause serious bacterial infections, especially skin and soft tissue infections (SSTI). Here, we describe a case of severe subcutaneous abscess due to Panton-Valentine leucocidin (PVL)-positive CA-MRSA in an infant without underlying diseases.

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We report a case of bacteremia caused by Bacillus subtilis variant natto after a gastrointestinal perforation in a patient in Japan. Genotypic and phenotypic studies of biotin identified B. subtilis var.

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Streptococcus pneumoniae is one of the leading causes of meningitis in children. In Japan, since the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13), the number of pneumococcal meningitis due to non-PCV13 serotypes in children has increased. To clarify the clinical outcomes, serotype distributions, and antimicrobial susceptibility of isolated S.

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After the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13), serotype replacement has occurred in Japan, and serotype 24 has become the most common serotype in paediatric invasive pneumococcal disease (IPD). To understand the characteristics of serotype 24-IPD in Japanese children in the post-PCV13 era, we conducted a retrospective study in children aged ≤15 years from 2010 to 2020 using a database of paediatric IPD surveillance in Chiba prefecture, Japan. We identified a total of 357 IPD cases and collected clinical information on 225 cases (24: 32 cases, non-24: 193 cases).

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Hematological malignancy and solid tumor are major risks for invasive pneumococcal disease. Thirteen-valent pneumococcal conjugate vaccine (PCV13) is recommended for immunocompromised patients aged 6 years and older and adults who had not received the vaccine previously. However, vaccination for these individuals is not publicly subsidized in Japan.

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Cryptococcus neoformans, basidiomycetous pathogenic yeast, is basically an environmental fungus and, therefore, challenged by ever changing environments. In this study, we focused on how C. neoformans responds to stress caused by cadmium that is one of high-risk pollutants.

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Patients with immune thrombocytopenia have increased risks of bleeding and thrombosis. The acute-phase treatment for venous thromboembolism complicated with severe immune thrombocytopenia involves a "platelet dilemma" in therapeutic decision-making.

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Introduction: In 2010, oral fluoroquinolone tosufloxacin (TFX) granules were released as the first oral respiratory quinolone for children in Japan.

Methods: To investigate the recent trend of H. influenzae strains with low susceptibility to quinolones in children, we analyzed the gene sequences of quinolone resistance-determining regions (QRDRs) of gyrA, gyrB, parC, and parE of 23 clinical isolates from 15 patients aged <15 years with an MIC of ≥0.

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Japan has not been able to eliminate rubella; as a result, the large rubella epidemic has occurred. Considering the complicated history of the vaccine policy in Japan, some susceptible populations became infected with rubella, resulting in an outbreak. We conducted a large serosurveillance against rubella in Chiba city after initiating free rubella-specific antibody testing and an immunization campaign during 2018-2019.

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Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a pathogen of major importance in pediatric patients. CA-MRSA can cause skin and soft tissue infection in children and young active adults with no predisposing factors, and life-threatening infections such as meningitis or necrotizing pneumonia have been reported. We report here a case of CA-MRSA meningitis complicated by acute left middle cerebral artery (MCA) infarction and necrotizing pneumonia in a previously healthy 1-month-old Vietnamese boy.

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Introduction: Neisseria lactamica is a commensal bacterium of the upper respiratory tract in humans and is closely related to Neisseria meningitidis. N. lactamica colonization may contribute to preventing N.

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The non-encapsulated Streptococcus pneumoniae (NESp) has emerged and increased in the clinical setting. The majority of NESp strains have been isolated from the nasopharynxes of healthy carriers and from respiratory specimens of patients with otitis media. NESp strains were shown to be more effective than encapsulated counterparts at forming biofilms.

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Studies on community-acquired pneumonia (CAP) and pneumococcal pneumonia (PP) related to the 13-valent pneumococcal conjugate vaccine (PCV13) introduction in Asia are scarce. This study aimed to investigate the epidemiological and microbiological determinants of hospitalised CAP and PP after PCV13 was introduced in Japan. This observational hospital-based surveillance study included children aged ⩽15 years, admitted to hospitals in and around Chiba City, Japan.

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Although the pneumococcal conjugate vaccine (PCV) has decreased the incidence of invasive pneumococcal disease (IPD) in children, cases of IPD caused by non-PCV serotypes have been increasing. Here, we report two cases of bacterial meningitis caused by meropenem-resistant Streptococcus pneumoniae; in both the cases, 13-valent PCV (PCV13) had been administered. The isolated S.

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A novel stereoisomer of eushearilide, 23-demethyleushearilide, was synthesized, and the structure-activity relationships of this compound along with known eushearilide stereoisomers were investigated in order to design novel lead compounds for the treatment of fungal infections. It was discovered that all of these congeners, together with the natural product, exhibited a wide range of antimicrobial activity against not only fungi but also against bacteria, including methicillin-resistant (MRSA) and vancomycin-resistant enterococci (VRE).

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. Certain nontypeable cannot be assigned a sequence type (ST) by Multilocus Sequence Typing (MLST) due to the lack of the gene, one of seven MLST loci in , which encodes a fucose-operon enzyme..

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