Publications by authors named "Fumiko Kirikae"

Clinical isolates of drug-resistant (isoniazid and/or rifampicin-resistant) Mycobacterium tuberculosis were obtained from 254 patients diagnosed with drug-resistant tuberculosis in Japan from April 2015 to March 2017 in National Hospital Organization hospitals. The 254 patients were approximately 32% of all 795 patients who were diagnosed with culture-confirmed drug-resistant tuberculosis from 2015 to 2016 nationwide in Japan. The whole-genome sequences of all the isolates from the 254 patients and the lineages of these isolates were determined, and phylogenetic trees were constructed based on single nucleotide polymorphism concatemers.

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Background: Antimicrobial peptides have a broad spectrum of antimicrobial activities and are attracting attention as promising next-generation antibiotics against multidrug-resistant (MDR) bacteria. The all-d-enantiomer [(KLAKLAK)] has been reported to have antimicrobial activity against and , and to be resistant to protein degradation in bacteria because it is composed of D-enantiomer compounds. In this study, we demonstrated that modification of [(KLAKLAK)] by the addition of an L-cysteine residue to its N- or C- terminus markedly enhanced its antimicrobial activities against Gram-negative bacteria such as MDR , , and .

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Peroxiredoxin (PRDX)1 is an antioxidant that detoxifies hydrogen peroxide and peroxinitrite. Compared with wild-type (WT) mice, Prdx1-deficient (Prdx1) mice showed increased susceptibility to Mycobacterium tuberculosis and lower levels of IFN-γ and IFN-γ-producing CD4 T cells in the lungs after M. tuberculosis infection.

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Mycobacterium tuberculosis contains a single rRNA operon that encodes targets for antituberculosis agents, including kanamycin. To date, only four mutations in the kanamycin binding sites of 16S rRNA have been reported in kanamycin-resistant clinical isolates. We hypothesized that another mutation(s) in the region may dramatically decrease M.

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MicroRNAs (miRNAs) are short, conserved, non-coding RNA molecules that repress translation, followed by the decay of miRNA-targeted mRNAs that encode molecules involved in cell differentiation, development, immunity and apoptosis. At least six miRNAs, including microRNA-155 (miR-155), were up-regulated when born marrow-derived macrophages from C57BL/6 mice were infected with Mycobacterium tuberculosis Erdman. C57BL/6 mice intravenously infected with Erdman showed up-regulation of miR-155 in livers and lungs.

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Resistance of Mycobacterium tuberculosis to pyrazinamide (PZA) derives mainly from mutations in the pncA gene. We developed a reverse hybridization-based line probe assay with oligonucleotide probes designed to detect mutations in pncA. The detection of PZA resistance was evaluated in 258 clinical isolates of M.

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Lipoteichoic acid (LTA) is a cell surface glycoconjugate of gram-positive bacteria and is reported to activate the innate immune system. We previously reported that purified LTA obtained from Enterococcus hirae has no immunostimulating activity, but a subfraction (Eh-AF) in an LTA fraction possesses activity. In this study, we established a mouse monoclonal antibody neutralizing the activity of Eh-AF and investigated its inhibitory effects.

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We developed a DNA sequencing-based method to detect mutations in the genome of drug-resistant Mycobacterium tuberculosis. Drug resistance in M. tuberculosis is caused by mutations in restricted regions of the genome.

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Screening of 120 taxanes identified a number of compounds that exhibited significant antituberculosis activity. Rational optimization of selected compounds led to the discovery that the C-seco-taxane-multidrug-resistance (MDR) reversal agents (C-seco-TRAs) are noncytotoxic at the upper limit of solubility and detection (>80 microM), while maintaining MIC(99) values of 1.25-2.

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We analyzed genetic variations of angiotensin-converting enzyme 2 (ACE2), considering that it might influence patients' susceptibility to severe acute respiratory syndrome-associated coronavirus (SARS-CoV) or development of SARS as a functional receptor. By cloning of the full-length cDNA of the ACE2 gene in the lung, where replication occurs on SARS-CoV, it was shown that there are different splicing sites. All exons including the new alternative exon, exon-intron boundaries, and the corresponding 5'-flanking region of the gene were investigated and 19 single nucleotide polymorphisms (SNPs) were found.

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We hypothesized that host antiviral genes induced by type I interferons might affect the natural course of severe acute respiratory syndrome (SARS). We analyzed single nucleotide polymorphisms (SNPs) of 2',5'-oligoadenylate synthetase 1 (OAS-1), myxovirus resistance-A (MxA), and double-stranded RNA-dependent protein kinase in 44 Vietnamese SARS patients with 103 controls. The G-allele of non-synonymous A/G SNP in exon 3 of OAS-1 gene showed association with SARS (p=0.

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The genomes of 28 bacterial strains, including mycobacterial species Mycobacterium tuberculosis and Mycobacterium bovis, were analyzed for the presence of a special class of microsatellite, that of trinucleotide repeat sequences (TRS). Results of a search of all 10 possible TRS motifs (i.e.

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We show that Proteus vulgaris O25 (PO25) lipopolysaccharide (LPS) induced an anaphylactoid reaction not only in wild-type and in lipid A non-responding mice but also in recombinase-activating gene-2-deficient (RAG-2(-/-)) and in mast cell-deficient (W/Wv) animals. Western blot analysis indicated that PO25 LPS bound to Ra-reactive factor (RaRF), the complex of mannan-binding lectins (MBL) and MBL-associated serine proteases. Binding of RaRF to PO25 LPS led to the activation of C4 component without participation of either C1 or Ig, via the lectin pathway.

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A series of new taxoids modified at the C-3', C-3'N, C-10, C-2 and C-7 positions has been designed, synthesized and evaluated for their potency to induce NO and TNF production by peritoneal murine macrophages (Mphi) from LPS-responsive C3H/HeN and LPS-hyporesponsive C3H/HeJ strains and human blood cells, and for their ability to inhibit the growth of Mphi-like cell lines J774.1 and J7.DEF3.

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An immunoglobulin enriched bovine colostrum preparation, IMMULAC (New Zealand Dairy Group, Cambridge, New Zealand), contains antibodies against various bacterial antigens. In the present study, we investigated the protective effects of a commercial bovine colostrum preparation against infections with enterohaemorrhagic Escherichia coli (EHEC) O157:H7 in a murine model. Balb/c mice were given drinking water containing streptomycin for 3 days before and following oral challenge with streptomycin-resistant EHEC O157:H7 strain (O157-SM(R)).

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Bacteroides vulgatus has been shown to be involved in the aggravation of colitis. Previously, we separated two potent virulence factors, capsular polysaccharide (CPS) and lipopolysaccharide (LPS), from a clinical isolate of B. vulgatus and characterized the structure of CPS.

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As assessed by the lipopolysaccharide (LPS)-specific chromogenic Limulus amoebocyte lysate (LAL) assay, Helicobacter pylori LPS extracted by the phenol-water procedure showed full potency to coagulate LAL, as did LPS from Salmonella minnesota and Escherichia coli. However, pretreatment of H. pylori LPS with polymyxin B, which easily destroys the endotoxic activity of enterobacterial LPS/lipid A, had little effect on the LAL coagulation activity, although the same treatment of E.

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The saccharide constituents of lipopolysaccharides (LPS) of Proteus spp. vary with the strain and contain unique components about which little is known. The biological activities of LPS and lipid A from S- and R-forms of 10 Proteus strains were examined.

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The ability of several Pseudomonas aeruginosa exo-enzymes, including exotoxin A (ETA), to induce inflammation and their influence on endotoxin-induced tumour necrosis factor (TNF) production in murine lung were evaluated. Intratracheal administration of lipopolysaccharide (LPS; 0.1-10 microg/mouse), 2(-1) LD50 of P.

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