640 results match your criteria: "International Research Center for Infectious Diseases.[Affiliation]"

Aims: To investigate the effects of Lactococcus lactis subsp. lactis strains LL100933 and LL12007 on the host defense mechanisms of Caenorhabditis elegans against pathogenic infections and stressors.

Methods And Results: C.

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Microglia-resident immune cells in the central nervous system-undergo morphological and functional changes in response to signals from the local environment and mature into various homeostatic states. However, niche signals underlying microglial differentiation and maturation remain unknown. Here, we show that neuronal micronuclei (MN) transfer to microglia, which is followed by changing microglial characteristics during the postnatal period.

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Development of a novel modified selective medium cefixime-tellurite-phosphate-xylose-rhamnose MacConkey agar for isolation of Escherichia albertii and its evaluation with food samples.

Int J Food Microbiol

January 2025

Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58, Rinkuourai-kita, Izumisano, Osaka 598-8531, Japan; Graduate School of Veterinary Science, Osaka Metropolitan University, Osaka, Japan; Asian Health Science Research Institute, Osaka Metropolitan University, Osaka, Japan; Osaka International Research Center for Infectious Diseases, Osaka Metropolitan University, 1-58, Rinkuourai-kita, Izumisano, Osaka 598-8531, Japan. Electronic address:

Since cefixime and tellurite are known to inhibit most bacteria belonging to Enterobacterales, we found that addition of tellurite inhibited E. albertii growth in Luria Bertani broth but not in tryptic soy broth (TSB), and addition of phosphate and soy peptone enhanced E. albertii growth in TSB in presence of tellurite.

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Microthrombus formation is associated with COVID-19 severity; however, the detailed mechanism remains unclear. In this study, we investigated mouse models with severe pneumonia caused by SARS-CoV-2 infection by using our in vivo two-photon imaging system. In the lungs of SARS-CoV-2-infected mice, increased expression of adhesion molecules in intravascular neutrophils prolonged adhesion time to the vessel wall, resulting in platelet aggregation and impaired lung perfusion.

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Purpose: Flotation methods are widely used to detect oocysts/cysts of protozoans and eggs of helminths, except trematodes. However, details regarding the concentration and recovery rates of these parasites are poorly understood.

Methods: Using Eimeria tenella oocysts as a model parasite, the present study evaluated three check points: (1) the proportion of parasites that remain floating in flotation solution (sucrose or saturated saline) during centrifugation, (2) the proportion of oocysts that naturally float after addition of flotation solution after centrifugation, and (3) the rate of recovery on cover slips after completion of the flotation protocol.

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Development of broadly protective influenza B vaccines.

NPJ Vaccines

January 2025

Department of Pathobiological Sciences, Influenza Research Institute, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, USA.

Influenza B viruses pose a significant threat to global public health, leading to severe respiratory infections in humans and, in some cases, death. During the last 50 years, influenza B viruses of two antigenically distinct lineages (termed 'Victoria' and 'Yamagata') have circulated in humans, necessitating two different influenza B vaccine strains. In this study, we devised a novel vaccine strategy involving reciprocal amino acid substitutions at sites where Victoria- and Yamagata-lineage viruses differ, leading to the generation of 'hybrid' vaccine viruses with the potential to protect against both lineages.

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Booster COVID-19 mRNA vaccination ameliorates impaired B-cell but not T-cell responses in older adults.

Front Immunol

December 2024

Department of Life Science Frontiers, Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan.

Age-associated differences in the effect of repetitive vaccination, particularly on memory T-cell and B-cell responses, remain unclear. While older adults (aged ≥65 years) exhibited enhanced IgG responses following COVID-19 mRNA booster vaccination, they produced fewer spike-specific circulating follicular helper T cells-1 than younger adults. Similarly, the cytotoxic CD8 T-cell response remained diminished with reduced PD-1 expression even after booster vaccination compared with that in younger adults, suggesting impaired memory T-cell activation in older adults.

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was recently reported as a novel species. Here, we present the whole-genome sequence of strain MH-1 isolated from homemade pickled Chinese cabbage in Japan. These genomic data have the potential to help clarify the role of species in fermented foods.

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Malaria rapid diagnostic tests (RDTs) targeting the Plasmodium falciparum histidine-rich protein 2 (PfHRP2) are widely used to diagnose P. falciparum infection. However, reports of P.

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U-73122, a phospholipase C inhibitor, impairs lymphocytic choriomeningitis virus virion infectivity.

J Gen Virol

December 2024

Laboratory of Emerging Viral Diseases, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan.

Lassa virus (LASV) is an Old World (OW) mammarenavirus that causes Lassa fever, a life-threatening acute febrile disease endemic in West Africa. Lymphocytic choriomeningitis virus (LCMV) is a worldwide-distributed, prototypic OW mammarenavirus of clinical significance that has been largely neglected as a human pathogen. No licensed OW mammarenavirus vaccines are available, and the current therapeutic option is limited to the off-label use of ribavirin, which offers only partial efficacy.

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Antiviral humoral immunity induced by JN.1 monovalent mRNA vaccines against SARS-CoV-2 omicron subvariants including JN.1, KP.3.1.1, and XEC.

Lancet Infect Dis

December 2024

Division of Systems Virology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan; International Research Center for Infectious Diseases, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan; International Vaccine Design Center, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan; Graduate School of Medicine, The University of Tokyo, Tokyo, Japan; Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan; Collaboration Unit for Infection, Joint Research Center for Human Retrovirus infection, Kumamoto University, Kumamoto, Japan; MRC-University of Glasgow Centre for Virus Research, Glasgow, UK. Electronic address:

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Alphaherpesviruses, including herpes simplex virus type 1 (HSV-1) and pseudorabies virus (PRV), are neurotropic double-stranded DNA viruses. Alphaherpesviruses control the expression of various host factors to ensure efficient infection and propagation. Recently, HSV-1 was found to upregulate Arc/Arg3.

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Dysbiosis of gut microbiota in COVID-19 is associated with intestinal DNA phage dynamics of lysogenic and lytic infection.

Microbiol Spectr

January 2025

Division of Infectious Diseases, Advanced Clinical Research Center, the Institute of Medical Science, the University of Tokyo, Tokyo, Japan.

This study compared intestinal DNA phage dynamics and gut microbiota changes observed at the onset of coronavirus disease 2019 (COVID-19). The study participants included 19 healthy individuals and 19 patients with severe acute respiratory syndrome coronavirus 2 infection. Significant differences were observed in the diversity of the intestinal DNA virome after the onset of COVID-19 compared with that in healthy individuals.

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TNF-α exacerbates SARS-CoV-2 infection by stimulating CXCL1 production from macrophages.

PLoS Pathog

December 2024

Division of Viral Infection, Department of Infectious Disease Control, International Research Center for Infectious Diseases, Institute of Medical Science, The University of Tokyo, Tokyo, Japan.

Since most genetically modified mice are C57BL/6 background, a mouse-adapted SARS-CoV-2 that causes lethal infection in young C57BL/6 mice is useful for studying innate immune protection against SARS-CoV-2 infection. Here, we established two mouse-adapted SARS-CoV-2, ancestral and Delta variants, by serial passaging 80 times in C57BL/6 mice. Although young C57BL/6 mice were resistant to infection with the mouse-adapted ancestral SARS-CoV-2, the mouse-adapted SARS-CoV-2 Delta variant caused lethal infection in young C57BL/6 mice.

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[Data-Driven Research for Understanding and Predicting Viral Epidemics and Evolution].

Uirusu

December 2024

Division of Systems Virology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo.

The era of big data has begun in life sciences, and virology is no exception. Especially since COVID-19, virology has become one of the most genome data-rich fields in life sciences. In this article, I will introduce the new paradigm of "understanding and predicting viral epidemics and evolution, " made possible by the emergence of vast amounts of genome data, focusing on my research to date.

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Differential vasoproliferative traits of strains associated with autotransporter BafA variants.

Microbiol Spectr

January 2025

Laboratory of Bacterial Zoonoses, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan.

a Gram-negative facultative intracellular bacterium, is the etiological agent of cat-scratch disease and also causes bacillary angiomatosis in immunocompromised individuals. Although the ability to promote vascular endothelial cell proliferation differs among species, variations among strains within remain unclear. angiogenic factor A (BafA) and adhesin A (BadA) have been identified as autotransporters of that are involved in endothelial cell proliferation.

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Disinfection effect of ozonated water on SARS-CoV-2 in the presence of salivary proteins.

J Hosp Infect

January 2025

Panasonic Corporation, Living Appliances and Solutions Company, Kusatsu, Shiga, Japan.

Background: Ozonated water is expected to be an effective disinfectant for SARS-CoV-2 present on environmental fomites; however, ozone is consumed by organic substances, resulting in attenuation of its effect. SARS-CoV-2 present in saliva can contaminate environmental surfaces; therefore, it is essential to understand the effect of organic substances in saliva on the disinfectant properties of ozonated water.

Aim: To assess organic factors in saliva and the extent to which they diminish the effect of ozonated water on SARS-CoV-2.

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Virological characteristics of the SARS-CoV-2 XEC variant.

Lancet Infect Dis

December 2024

Division of Systems Virology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan; Graduate School of Frontier Sciences, The University of Tokyo, Chiba, Japan; Graduate School of Medicine, The University of Tokyo, Tokyo, Japan; Collaboration Unit for Infection, Joint Research Center for Human Retrovirus Infection, Kumamoto University, Kumamoto, Japan; International Research Center for Infectious Diseases, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan; International Vaccine Design Center, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan; MRC-University of Glasgow Centre for Virus Research, Glasgow, UK. Electronic address:

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Cryptosporidium is a waterborne pathogen that causes diarrhea in vertebrates and humans (mainly C. hominis and C. parvum).

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Estimating influenza vaccine effectiveness among older adults using an integrated administrative database and the implications of potential bias: A population-based cohort study in Japan.

Vaccine

December 2024

Center for Surveillance, Immunization, and Epidemiologic Research, National Institute of Infectious Diseases, J1601 Iidabashi Plano Stage Building, 2-7-2 Fujimi, Chiyoda-ku, Tokyo 102-0071, Japan; Center for Field Epidemic Intelligence, Research, and Professional Development, National Institute of Infectious Diseases, J1601 Iidabashi Plano Stage Building, 2-7-2 Fujimi, Chiyoda-ku, Tokyo 102-0071, Japan.

Background: Japan lacks an established framework for routine seasonal influenza vaccine effectiveness (SIVE) assessment at the national and municipal levels. This study aimed to estimate SIVE among older adults using an innovative population-based administrative database linking medical fee claims data with vaccination records, while also exploring its potential bias.

Methods: In this retrospective population-based cohort study, we assessed SIVE against medically attended influenza during the 2017/18 season among older adults aged ≥65 years in a Japanese city.

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Campylobacter fetus is a zoonotic pathogen. Although the precise virulence mechanisms have not yet been fully elucidated, cytolethal distending toxin (CDT) is considered as one of the well-characterized virulence factors in Campylobacter. In silico analysis of the genome of C.

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Article Synopsis
  • Since 2019, SARS-CoV-2 has mutated, leading to various pandemic and epidemic waves that involve changes in its spike protein, which is key for the virus's entry into cells.
  • Researchers studied the spike proteins from variants BA.2.86 and JN.1, discovering structures where ACE2 receptor binds to the spike protein in both up and down conformations.
  • Their findings suggest that the down-conformation of the receptor-binding domain (RBD) is an important intermediate state that helps facilitate the virus's entry, with specific mutations like K356T impacting infectivity and resistance to neutralizing antibodies.
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Serine affects engulfment during the sporulation process in Clostridium perfringens strain SM101.

Anaerobe

December 2024

Graduate School of Veterinary Science, Osaka Metropolitan University, 1-58 Rinku Ourai Kita, Izumisano, Osaka, 598-8531, Japan; Osaka International Research Center for Infectious Diseases, Osaka Metropolitan University, 1-58 Rinku Ourai Kita, Izumisano, Osaka, 598-8531, Japan; Research Center for Food Safety, Osaka Metropolitan University, 1-58 Rinku Ourai Kita, Izumisano, Osaka, 598-8531, Japan.

Objectives: Although Clostridium perfringens sporulation is a key event in the pathogenesis of food-borne illness, the molecules and underlying mechanisms responsible for regulating sporulation are incompletely understood. The present study sought to identify amino acids that affect sporulation in C. perfringens strain SM101.

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Background: Humoral bactericidal activity was first recognized nearly a century ago. However, the extent of inter-individual heterogeneity and the mechanisms underlying such heterogeneity beyond antibody or complement systems have not been well studied.

Methods: The plasma bactericidal activity of five healthy volunteers were tested against 30 strains of Gram-negative uropathogens, Klebsiella pneumoniae and Escherichia coli, associated with bloodstream infections.

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Inhibitory effects of sucrose palmitic acid ester on the germination-to-outgrowth process of Clostridium perfringens SM101 spores.

Int J Food Microbiol

January 2025

Department of Veterinary Science, School of Life and Environmental Sciences, Osaka Metropolitan University, Izumisano, Osaka 598-8531, Japan; Graduate School of Veterinary Science, Osaka Metropolitan University, Izumisano, Osaka 598-8531, Japan; Research Institute for Food Safety, Osaka Metropolitan University, Izumisano, Osaka 598-8531, Japan; Osaka International Research Center for Infectious Diseases, University Public Cooperation Osaka, Osaka, Japan. Electronic address:

As a commercially available esterified compound derived from sucrose and palmitoyl acids, sucrose ester palmitic acid (SEPA) has been used as an emulsifier in food processing. It possesses antibacterial activity against vegetative and spore-forming bacteria, including Clostridium, Moorella, Bacillus, and Geobacillus species, prompting the food industry to use it as a food additive to achieve a desirable shelf life; however, the precise mechanism by which the compound affects the physiological processes of bacteria and how it inhibits bacterial growth remains unclear. In this study, we focused on the inhibitory effect of SEPA on the germination-to-outgrowth process of Clostridium perfringens SM101 spores, a strain widely used as a model of C.

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