Publications by authors named "Itsuki Taniguchi"

Yersinia pseudotuberculosis (Ypt) is a gram-negative bacterium that infects both humans and animals primarily through fecal‒oral transmission. While Ypt causes acute gastroenteritis in humans, an association with Kawasaki disease (KD), a disease that primarily affects infants and young children and causes multisystemic vasculitis, has also been suspected. Although KD represents a significant health concern worldwide, the highest annual incidence rate is reported in Japan.

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  • Shiga toxin-producing E. coli (STEC) causes severe gastrointestinal issues, particularly linked to Stx2, which poses greater risks than Stx1.
  • A study of 71 strains in the O145:H28 lineage reveals the dynamic nature of Stx phages, including their acquisition, transfer, and variations affecting Stx2 production levels.
  • Short-tailed Stx2 phages are associated with higher production levels of Stx2 than long-tailed variants, highlighting genetic differences that influence these levels.
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  • Microbiota composed of fungi and bacteria significantly influences the physiological functions of larvae, though the specific species and their impacts are not well understood.
  • The study found that a specific yeast is crucial for larval growth in the early fermentation stages, while a particular bacterium takes over as the primary growth supporter in later stages, needing the coexistence of yeasts and lactic acid bacteria for stability.
  • The microbiota enhances larval nutrition and promotes gene activity related to cell growth and metabolism, highlighting the important role of these microbial species during developmental transitions.
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  • Plasmids contribute significantly to the genetic diversity of bacteria, as evidenced by the study analyzing 142 closed genomes, which identified 132 plasmids in various strains, highlighting their role in genome evolution.
  • The research found that while there was no significant difference in plasmid numbers between clinical and non-clinical strains, certain hospital-adapted lineages (like clade 2) contained more plasmids, with a notable proportion being associated with antimicrobial and heavy metal resistance.
  • Clustering analysis revealed distinct groups of plasmids with varied GC content and highlighted their potential for interclade transmission and wider host-range capabilities, suggesting a complex ecological relationship among strains in different environments. *
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  • Shiga toxin (Stx), produced by Stx-producing E. coli (STEC), is crucial for the bacteria's virulence and is encoded by bacteriophages known as Stx phages.
  • A study focusing on the O26:H11 STEC lineage (specifically ST21) revealed significant genetic diversity among Stx1a phages, indicating various evolutionary changes, including the replacement of phages.
  • Additionally, the research showed notable differences in Stx1 toxin production linked to variations in Stx1 phages and host factors, emphasizing the complexity of phage-host interactions in toxin production.
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  • The study focuses on Shiga toxin-producing E. coli (STEC), particularly on the O165:H25 strain and its relationship to closely related strains, defining them all as clonal complex 119 (CC119).
  • Researchers conducted whole-genome sequencing of 202 strains to analyze their genetic similarities and differences, focusing on the presence and behavior of specific phages and virulence genes.
  • The findings revealed that the CC119 lineage retains certain genetic traits that enhance virulence, but also shows notable variations in toxin production and lacks genes typical for tellurite resistance, indicating potential vulnerabilities in these strains.
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  • * The study involved genome sequencing of 510 strains, including 147 from Japan, and analyzed variations in Stx2 production levels, which are associated with disease severity.
  • * Results showed distinct genetic diversity in Stx2a phages among the lineages, particularly that SG8_30 strains produced more Stx2 and caused more severe illnesses compared to SG8_32 strains.
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  • Lactose utilization in Escherichia coli is generally detected on lactose-containing media, but some Shiga toxin-producing strains (O121:H19) exhibit a delayed lactose utilization (DLU) phenotype, requiring 48 hours for detection instead of the usual 24 hours.
  • The DLU phenotype is linked to an insertion sequence (IS) disrupting the lactose utilization gene, and its effects can only be observed after exposure to lactose.
  • Research revealed that the IS can be excised, allowing the reactivation of the lactose utilization gene, and showed that most circulating O121:H19 strains harbor this IS insertion, explaining the prevalence of the DLU phenotype.
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  • The text discusses a significant nosocomial pathogen responsible for opportunistic infections and emphasizes the threat posed by emerging multidrug-resistant (MDR) strains to global health.
  • A large-scale genome analysis of this pathogen and its closely related species was conducted, identifying 14 distinct clades based on genomic characteristics.
  • Clades 1 and 2 contained most hospital-related isolates with high antimicrobial resistance, suggesting they are adapted to clinical environments, while new genomic insights may lead to a reevaluation of the pathogen's classification and understanding of its evolution.
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  • Shiga toxin (Stx)-producing Escherichia coli (STEC), particularly O121:H19, are emerging foodborne pathogens linked to serious illnesses like hemorrhagic colitis and hemolytic uremic syndrome.
  • A global whole genome sequencing analysis of 638 O121:H19 strains revealed four distinct lineages, with significant differences in their virulence factors and prophage characteristics between the major lineages L1 and L3.
  • The study highlights that strains in lineage L1 produce much higher levels of Stx2a toxin due to their highly conserved short-tailed phage genomes, while lineage L3 shows notable genetic diversity with long-tailed phages.
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Shiga toxin-producing (STEC) is a major intestinal pathogen and causes serious gastrointestinal illness, which includes diarrhea, hemorrhagic colitis, and life-threatening hemolytic uremic syndrome. The major virulence factors of STEC are Shiga toxins (Stx1 and Stx2), which belong to the AB-type toxin family. Among several subtypes of Stx1 and Stx2, the production of Stx2a is thought to be a risk factor for severe STEC infections, but Stx2a production levels vary markedly between STEC strains, even strains with the same serotype.

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We have previously reported a novel homozygous 4-bp deletion in DDHD1 as the responsible variant for spastic paraplegia type 28 (SPG28; OMIM#609340). The variant causes a frameshift, resulting in a functionally null allele in the patient. DDHD1 encodes phospholipase A1 (PLA1) catalyzing phosphatidylinositol to lysophosphatidylinositol (LPI).

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Background: Epidemiological studies of DNA methylation profiles may uncover the molecular mechanisms through which genetic and environmental factors contribute to the risk of multifactorial diseases. There are two types of commonly used DNA bioresources, peripheral blood cells (PBCs) and EBV-transformed lymphoblastoid cell lines (LCLs), which are available for genetic epidemiological studies. Therefore, to extend our knowledge of the difference in DNA methylation status between LCLs and PBCs is important in human population studies that use these DNA sources to elucidate the epigenetic risks for multifactorial diseases.

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The functional roles of SNPs within the 8q24 gene desert in the cancer phenotype are not yet well understood. Here, we report that CCAT2, a novel long noncoding RNA transcript (lncRNA) encompassing the rs6983267 SNP, is highly overexpressed in microsatellite-stable colorectal cancer and promotes tumor growth, metastasis, and chromosomal instability. We demonstrate that MYC, miR-17-5p, and miR-20a are up-regulated by CCAT2 through TCF7L2-mediated transcriptional regulation.

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