Publishing type：Part of collection (book)   Publisher：Springer US  

DOI： 10.1007/978-1-0716-4096-8_4

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Human norovirus (HuNoV) is an enteric infectious pathogen belonging to the Caliciviridae family that causes occasional epidemics. Circulating alcohol-tolerant viral particles that are readily transmitted via food-borne routes significantly contribute to the global burden of HuNoV-induced gastroenteritis. Moreover, contact with enzymes secreted by other microorganisms in the environment can impact the infectivity of viruses. Hence, understanding the circulation dynamics of Caliciviridae is critical to mitigating epidemics. Accordingly, in this study, we screened whether environmentally abundant secretase components, particularly proteases, affect Caliciviridae infectivity. Results showed that combining Bacillaceae serine proteases with epsilon-poly-L-lysine (EPL) produced by Streptomyces-a natural antimicrobial-elicited anti-Caliciviridae properties, including against the epidemic HuNoV GII.4_Sydney_2012 strain. In vitro and in vivo biochemical and virological analyses revealed that EPL has two unique synergistic viral inactivation functions. First, it maintains an optimal pH to promote viral surface conformational changes to the protease-sensitive structure. Subsequently, it inhibits viral RNA genome release via partial protease digestion at the P2 and S domains in the VP1 capsid. This study provides new insights regarding the high-dimensional environmental interactions between bacteria and Caliciviridae, while promoting the development of protease-based anti-viral disinfectants.

DOI： 10.1038/s41598-024-65963-9

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

MraY (phospho-N-acetylmuramoyl-pentapeptide-transferase) inhibitory natural products are attractive molecules as candidates for a new class of antibacterial agents to combat antimicrobial-resistant bacteria. Structural optimization of these natural products is required to improve their drug-like properties for therapeutic use. However, chemical modifications of these natural products are painstaking tasks due to complex synthetic processes, which is a bottleneck in advancing natural products to the clinic. Here, we develop a strategy for a comprehensive in situ evaluation of the build-up library, which enables us to streamline the preparation of the analogue library and directly assess its biological activities. We apply this approach to a series of MraY inhibitory natural products. Through construction and evaluation of the 686-compound library, we identify promising analogues that exhibit potent and broad-spectrum antibacterial activity against highly drug-resistant strains in vitro as well as in vivo in an acute thigh infection model. Structures of the MraY-analogue complexes reveal distinct interaction patterns, suggesting that these analogues represent MraY inhibitors with unique binding modes. We further demonstrate the generality of our strategy by applying it to tubulin-binding natural products to modulate their tubulin polymerization activities.

DOI： 10.1038/s41467-024-49484-7

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Lipoteichoic acid (LTA) in the gram-positive bacterial cell wall acts as an immunomodulatory factor in host cells. The chemical structures vary among bacterial species and strains, and may be related to biological activities. In our previous work, much higher immunoglobulin A (IgA)-inducing activity was observed in cells of the Apilactobacillus genus (Apilactobacillus kosoi 10HT, Apilactobacillus apinorum JCM 30765T, and Apilactobacillus kunkeei JCM 16173T) than other lactic acid bacteria, and their LTA was responsible for the activity. In the present study, we elucidated the chemical structures of LTA from these Apilactobacillus strains to explore the structure-function relationship of the IgA-inducing activity. The 1H-nuclear magnetic resonance spectra suggested that their LTA structures were similar. All have a poly-glycerolphosphate main chain, which comprised 12 to 20 average number of the repeating units, with partial substitutions of glucose(α1-, glucosyl(α1-2)glucose(α1- (α-linked-kojibiose), and l-lysine at the C-2 hydroxy group of the glycerol residue. l-Lysine is a substituent never seen before in LTA, and is a probable characteristic of the Apilactobacillus genus. Removal of l-lysine residue from LTA by mild alkaline treatment decreased IgA induction in murine Peyer's patch experiments. The novel l-lysine residue in Apilactobacillus LTA plays a crucial role in the remarkably high IgA-inducing activity.

DOI： 10.1016/j.ijbiomac.2024.132540

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.onehlt.2024.100715

researchmap

Language：English  

UNLABELLED: Acinetobacter baumannii is highly resistant to antimicrobial agents, and XDR strains have become widespread. A. baumannii has developed resistance to colistin, which is considered the last resort against XDR Gram-negative bacteria, mainly caused by lipooligosaccharide (LOS) phosphoethanolamine (pEtN) and/or galactosamine (GalN) modifications induced by mutations that activate the two-component system (TCS) pmrAB. Although PmrAB of A. baumannii has been recognized as a drug resistance factor, its function as TCS, including its regulatory genes and response factors, has not been fully elucidated. In this study, to clarify the function of PmrAB as TCS, we elucidated the regulatory genes (regulon) of PmrAB via transcriptome analysis using pmrAB-activated mutant strains. We discovered that PmrAB responds to low pH, Fe2+, Zn2+, and Al3+. A. baumannii selectively recognizes Fe2+ rather than Fe3+, and a novel region ExxxE, in addition to the ExxE motif sequence, is involved in the environmental response. Furthermore, PmrAB participates in the phosphoethanolamine modification of LOS on the bacterial surface in response to metal ions such as Al3+, contributing to the attenuation of Al3+ toxicity and development of resistance to colistin and polymyxin B in A. baumannii. This study demonstrates that PmrAB in A. baumannii not only regulates genes that play an important role in drug resistance but is also involved in responses to environmental stimuli such as metal ions and pH, and this stimulation induces LOS modification. This study reveals the importance of PmrAB in the environmental adaptation and antibacterial resistance emergence mechanisms of A. baumannii. IMPORTANCE: Antimicrobial resistance (AMR) is a pressing global issue in human health. Acinetobacter baumannii is notably high on the World Health Organization's list of bacteria for which new antimicrobial agents are urgently needed. Colistin is one of the last-resort drugs used against extensively drug-resistant (XDR) Gram-negative bacteria. However, A. baumannii has become increasingly resistant to colistin, primarily by modifying its lipooligosaccharide (LOS) via activating mutations in the two-component system (TCS) PmrAB. This study comprehensively elucidates the detailed mechanism of drug resistance of PmrAB in A. baumannii as well as its biological functions. Understanding the molecular biology of these molecules, which serve as drug resistance factors and are involved in environmental recognition mechanisms in bacteria, is crucial for developing fundamental solutions to the AMR problem.

DOI： 10.1128/jb.00435-23

PubMed

J-GLOBAL

researchmap

Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Abstract

Background

Dialysis units have been concerned that the corroded metal parts of pumps used in hemodialysis might not allow sterility of the pump to be ensured due to bacterial contamination, even after cleaning and disinfection are performed after dialysis treatment. The purpose of this study was to clarify the effectiveness of the cleaning/disinfection process in eliminating bacterial contamination of the dialysate in pumps with and without metal corrosion.

Methods

A suspension of Pseudomonas aeruginosa [10 colony-forming unit (CFU)/mL] was introduced into pumps without or with corrosion of the metal parts, and the flow in the dialysis circuit was stopped for 6, 12, or 18 h. Then, after cleaning and disinfection of the circuit with a sodium-hypochlorite-containing reagent, the amounts of live bacteria in the terminal dialysate and on the surface of the metal parts of the pump were counted.

Results

Irrespective of the presence or absence of metal corrosion, bacteria were detected, even after cleaning and disinfection, on the surfaces of the pump parts that had been left in contact with the bacterial suspension for more than 12 h. However, on the surfaces of the pump parts showing metal corrosion, the bacterial numbers increased dramatically after 18 h of flow stoppage time following introduction of bacteria, and bacteria were even detected in the terminal dialysate despite cleaning/disinfection of the pump.

Conclusions

Corrosion of the metal parts used in pumps used for dialysis increases the risk of bacterial contamination of not only the pump parts and flow path of the dialysis machine but also the terminal dialysate, even if cleaning/disinfection is performed. For sterility assurance of the dialysis circuit and dialysate during routine use, it is necessary to eliminate corrosion of the metal parts of dialysis pumps during scheduled maintenance.

Other Link： https://link.springer.com/article/10.1186/s41100-024-00522-6/fulltext.html

DOI： 10.1186/s41100-024-00522-6

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

The mechanism underlying the anti-inflammatory effect of macrolide antibiotics, such as clarithromycin (CAM), remains to be clarified. The CAM-binding proteins 4-nitrophenylphosphatase domain and non-neuronal synaptosomal associated protein 25 (SNAP25)-like protein homolog (NIPSNAP) 1 and 2 are involved in the immune response and mitochondrial homeostasis. However, the axis between CAM-NIPSNAP-mitochondria and Toll-like receptor (TLR) and their molecular mechanisms remain unknown. In this study, we sought to elucidate the relationship between mitochondrial homeostasis mediated by NIPSNAP1 and 2 and the immunomodulatory effect of CAM. NIPSNAP1 or 2 knockdown (KD) by RNA interference impaired TLR4-mediated interleukin-8 (IL-8) production. Similar impairment was observed upon treatment with mitochondrial function inhibitors. However, IL-8 secretion was not impaired in NIPSNAP1 and 2 individual knockout (KO) and double KO (DKO) cells. Moreover, the oxygen consumption rate (OCR) in mitochondria measured using a flex analyzer was significantly reduced in NIPSNAP1 or 2 KD cells, but not in DKO cells. CAM also dose-dependently reduced the OCR. These results indicate that CAM suppresses the IL-8 production via the mitochondrial quality control regulated by temporary functional inhibition of NIPSNAP1 and 2. Our findings provide new insight into the mechanisms underlying cytokine production, including the TLR-mitochondria axis, and the immunomodulatory effects of macrolides.

DOI： 10.1038/s41598-024-52582-7

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Multidrug-resistant Neisseria gonorrhoeae is a serious concern worldwide. Resistance to β-lactam antibiotics occurs through mutations in penicillin-binding proteins (PBPs), acquisition of β-lactamases, and alteration of antibiotic penetration. Mosaic structures of penA, which encodes PBP2, play a major role in resistance to β-lactams, especially cephalosporins. Ceftriaxone (CRO) is recognized as the only satisfiable antibiotic for the treatment of gonococcal infections; however, CRO-resistant isolates have emerged in the community. Here, we examined the affinity of β-lactam antibiotics for recombinant PBP2 in a competition assay using fluorescence-labeled penicillin. We found no or little difference in the affinities of penicillins and meropenem (MEM) for PBP2 from cefixime (CFM)-reduced-susceptible strain and cephalosporin-resistant strain. However, the affinity of cephalosporins, including CRO, for PBP2 from the cephalosporin-resistant strain was markedly lower than that for PBP2 from the CFM-reduced-susceptible-resistant strain. Notably, piperacillin (PIP) showed almost the same affinity for PBP2 from penicillin-susceptible, CFM-reduced-susceptible, and cephalosporin (including CRO)-resistant strains. Thus, PIP/tazobactam and MEM are candidate antibiotics for the treatment of CRO-resistant/multidrug-resistant N. gonorrhoeae.

DOI： 10.1089/mdr.2023.0256

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

OBJECTIVES: It is feared that the serotype replacement of Streptococcus pneumoniae occurred by the introduction of pneumococcal vaccines as periodical inoculation leads to reduced efficacy of the approved vaccines and altered antimicrobial susceptibility. METHODS: We determined serotypes of 351 S. pneumoniae isolates collected at a commercial clinical laboratory in Hokkaido prefecture, Japan, from December 2018 to February 2019 by using the polymerase chain reaction procedure of the US Centers for Disease Control and Prevention. Antimicrobial susceptibility and resistance gene profiles were also examined. RESULTS: Vaccine coverage rates were 7.9% for 13-valent conjugate vaccine, and 32.5% for 23-valent polysaccharide vaccine, respectively. Non-typable strains were 19.7%. cpsA-positive isolates (group I), and null capsule clade (NCC)1, NCC2 and NCC3 (group II) comprised 31.3%, 28.4%, 32.8%, and 7.5% of the 69 non-typable strains, respectively. No penicillin-resistant/intermediate isolates were found; however, serotypes 35B and 15A/F showed low susceptibility to β-lactams. Only five strains (1.4%) were levofloxacin-resistant, and all were from the older persons, and three strains were serotype 35B. CONCLUSION: The progression of serotype replacement in non-invasive pneumococcal infections has occurred during the post-vaccine era in Japan, and non-encapsulated isolates, such as NCC, have increased. Antimicrobial susceptibility is not worsened.

DOI： 10.1016/j.ijregi.2023.07.002

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: Colistin (CST) is a last-line drug for multidrug-resistant Gram-negative bacterial infections. CST-heteroresistant Enterobacter cloacae complex (ECC) has been isolated. However, integrated analysis of epidemiology and resistance mechanisms based on the complete ECC species identification has not been performed. METHODS: Clinical isolates identified as "E. cloacae complex" by MALDI-TOF MS Biotyper Compass in a university hospital in Japan were analyzed. Minimum inhibitory concentrations of CST were determined by the broth microdilution method. The population analysis profiling (PAP) was performed for detecting the heteroresistant phenotype. The heat shock protein 60 (hsp60) cluster was determined from its partial nucleotide sequence. From the data of whole-genome sequencing, average nucleotide identity (ANI) for determining ECC species, multilocus sequence type, core genome single-nucleotide-polymorphism-based phylogenetic analysis were performed. phoPQ-, eptA-, and arnT-deleted mutants were established to evaluate the mechanism underlying colistin heteroresistance. The arnT mRNA expression levels were determined by reverse transcription quantitative PCR. RESULTS: Thirty-eight CST-resistant isolates, all of which exhibited the heteroresistant phenotype by PAP, were found from 138 ECC clinical isolates (27.5%). The prevalence of CST-resistant isolates did not significantly differ among the origin of specimens (29.0%, 27.8%, and 20.2% for respiratory, urine, and blood specimens, respectively). hsp60 clusters, core genome phylogeny, and ANI revealed that the CST-heteroresistant isolates were found in all or most of Enterobacter roggenkampii (hsp60 cluster IV), Enterobacter kobei (cluster II), Enterobacter chuandaensis (clusters III and IX), and Enterobacter cloacae subspecies (clusters XI and XII). No heteroresistant isolates were found in Enterobacter hormaechei subspecies (clusters VIII, VI, and III) and Enterobacter ludwigii (cluster V). CST-induced mRNA upregulation of arnT, which encodes 4-amino-4-deoxy-L-arabinose transferase, was observed in the CST-heteroresistant isolates, and it is mediated by phoPQ pathway. Isolates possessing mcr-9 and mcr-10 (3.6% and 5.6% of total ECC isolates, respectively) exhibited similar CST susceptibility and PAP compared with mcr-negative isolates. CONCLUSIONS: Significant prevalence (approximately 28%) of CST heteroresistance is observed in ECC clinical isolates, and they are accumulated in specific species and lineages. Heteroresistance is occurred by upregulation of arnT mRNA induced by CST. Acquisition of mcr genes contributes less to CST resistance in ECC.

DOI： 10.1186/s12941-023-00610-1

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Murine norovirus (MNV) is used widely as a practical alternative to human norovirus (HuNoV). Plaque-forming assays for MNV are important for developing therapeutic agents against HuNoV infections. Although agarose-overlay MNV assays have been reported, recent improvements in cellulose derivatives suggest that they could be optimized further, particularly with respect to improving the overlay material. To determine which overlay material is optimal for the MNV plaque assay, we compared four typical cellulose derivatives [microcrystalline cellulose (MCC), hydroxyethyl cellulose (HEC), hydroxypropyl methylcellulose (HPMC), and carboxymethyl cellulose (CMC)] with conventional agarose. We found that 3.5% (w/v) MCC-containing medium provided clear round-shaped plaques on RAW 264.7 cells 1 day after inoculation; the visibility of plaques was comparable with that of the original agarose-overlay assay. Removing residual MCC powder from the MCC-overlay assay before fixing was important for obtaining distinct plaques that are clearly countable. Finally, after calculating the plaque diameter as a percentage of well diameter, we found that 12- and 24-well plates were better than other plates for accurate plaque counting. The MCC-based MNV plaque assay is cost-effective and rapid, and produces plaques that are easy to count. Accurate virus quantification using this optimized plaque assay will enable reliable estimation of norovirus titers.

DOI： 10.1016/j.jviromet.2023.114715

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: Mycobacterium lentiflavum is a slow-growing nontuberculous mycobacterium that is widely distributed in soil and water systems, but it is sometimes pathogenic to humans. Although cases of M. lentiflavum infections are rare, 22 isolates of M. lentiflavum were identified at a single hospital in Japan. We suspected a nosocomial outbreak; thus, we conducted transmission pattern and genotype analyses. METHODS: Cases of M. lentiflavum isolated at Kushiro City General Hospital in Japan between May 2020 and April 2021 were analyzed. The patient samples and environmental culture specimens underwent whole-genome sequencing (WGS). Additionally, we retrospectively collected clinical data from patient medical records. RESULTS: Altogether, 22 isolates of M. lentiflavum were identified from sputum and bronchoalveolar lavage samples. Clinically, the instances with M. lentiflavum isolates were considered contaminants. In the WGS analysis, 19 specimens, including 18 patient samples and 1 environmental culture from the hospital's faucet, showed genetic similarity. The frequency of M. lentiflavum isolation decreased after we prohibited the use of taps where M. lentiflavum was isolated. CONCLUSIONS: WGS analysis identified that the cause of M. lentiflavum pseudo-outbreak was the water used for patient examinations, including bronchoscopy.

DOI： 10.1017/ice.2023.68

PubMed

researchmap

Language：English  

DOI： 10.1016/j.jgar.2022.12.008

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Chemical Society (ACS)  

DOI： 10.1021/jacs.2c12971

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Healthcare-associated infections have become a major health issue worldwide. One route of transmission of pathogenic bacteria is through contact with "high-touch" dry surfaces, such as handrails. Regular cleaning of surfaces with disinfectant chemicals is insufficient against pathogenic bacteria and alternative control methods are therefore required. We previously showed that warming to human-skin temperature affected the survival of pathogenic bacteria on dry surfaces, but humidity was not considered in that study. Here, we investigated environmental factors that affect the number of live bacteria on dry surfaces in hospitals by principal component analysis of previously-collected data (n = 576, for CFU counts), and experimentally verified the effect of warming to human-skin temperature on the survival of pathogenic bacteria on dry surfaces under humidity control. The results revealed that PCA divided hospital dry surfaces into four groups (Group 1~4) and hospital dry surfaces at low temperature and low humidity (Group 3) had much higher bacterial counts as compared to the others (Group 1 and 4) (p<0.05). Experimentally, warming to human-skin temperature (37°C with 90% humidity) for 18~72h significantly suppressed the survival of pathogenic bacteria on dry surfaces, such as plastic surfaces [p<0.05 vs. 15°C (Escherichia coli DH5α, Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, and blaNDM-5 E. coli)] or handrails [p<0.05 vs. 15~25°C (E. coli DH5α, S. aureus, P. aeruginosa, A. baumannii)], under moderate 55% humidity. Furthermore, intermittent heating to human-skin temperature reduced the survival of spore-forming bacteria (Bacillus subtilis) (p<0.01 vs. continuous heating to human-skin temperature). NhaA, an Na+/H+ antiporter, was found to regulate the survival of bacteria on dry surfaces, and the inhibitor 2-aminoperimidine enhanced the effect of warming at human-skin temperature on the survival of pathogenic bacteria (E. coli DH5α, S. aureus, A. baumannii) on dry surfaces. Thus, warming to human-skin temperature under moderate humidity is a useful method for impairing live pathogenic bacteria on high-touch surfaces, thereby helping to prevent the spread of healthcare-associated infections.

DOI： 10.1371/journal.pone.0291765

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

The development of new antibacterial drugs with different mechanisms of action is urgently needed to address antimicrobial resistance. MraY is an essential membrane enzyme required for bacterial cell wall synthesis. Sphaerimicins are naturally occurring macrocyclic nucleoside inhibitors of MraY and are considered a promising target in antibacterial discovery. However, developing sphaerimicins as antibacterials has been challenging due to their complex macrocyclic structures. In this study, we construct their characteristic macrocyclic skeleton via two key reactions. Having then determined the structure of a sphaerimicin analogue bound to MraY, we use a structure-guided approach to design simplified sphaerimicin analogues. These analogues retain potency against MraY and exhibit potent antibacterial activity against Gram-positive bacteria, including clinically isolated drug resistant strains of S. aureus and E. faecium. Our study combines synthetic chemistry, structural biology, and microbiology to provide a platform for the development of MraY inhibitors as antibacterials against drug-resistant bacteria.

DOI： 10.1038/s41467-022-35227-z

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Crohn's disease (CD) and ulcerative colitis (UC) are chronic inflammatory disorders of the gastrointestinal tract that share similar genetic risk factors. However, while fibrotic stricture of the intestine is a major characteristic of CD; it is rarely observed in UC. Deposition of collagen in the extracellular matrix contributes to the formation of fibrotic strictures in CD, but the underlying mechanisms are unknown. In the present study, we found that heat shock protein 47 (HSP47), a stress-response protein that acts as a molecular chaperone during the processing and secretion of collagen, expressed in the intestinal tissue from patients with CD. Serum HSP47 levels and anti-HSP47 antibody titers were significantly higher in patients with CD than in those with UC. Furthermore, anti-HSP47 antibody levels correlated significantly with fibrosis in CD. In addition, HSP47 inhibition significantly suppressed collagen production in fibroblasts in vitro. These findings suggest that HSP47 is a biomarker for differentiating fibrotic from non-fibrotic forms of CD. Additionally, we propose that HSP47 could be a potential target for treating fibrosis in patients with CD.

DOI： 10.1038/s41598-022-15153-2

PubMed

researchmap

Language：Japanese  

Ichushi

J-GLOBAL

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Lactic acid bacterium-containing fermentates provide beneficial health effects by regulating the immune response. A naturally fermented vegetable beverage, a traditional Japanese food, reportedly provides health benefits; however, the beneficial function of its bacteria has not been clarified. Apilactobacillus kosoi is the predominant lactic acid bacterium in the beverage. Using murine Peyer's patch cells, we compared the immunoglobulin A (IgA)-inducing activity of A. kosoi 10HT to those of 29 other species of lactic acid bacteria and found that species belonging to the genus Apilactobacillus (A. kosoi 10HT, A. apinorum JCM30765T, and A. kunkeei JCM16173T) possessed significantly higher activity than the others. Thereafter, lipoteichoic acids (LTAs), important immunostimulatory molecules of Gram-positive bacteria, were purified from the three Apilactobacillus species, and their IgA-inducing activity was compared to those of LTAs from Lactiplantibacillus plantarum JCM1149T and a probiotic strain, Lacticaseibacillus rhamnosus GG. The results revealed that LTAs from Apilactobacillus species had significantly higher activity than others. We also compared the LTA structure of A. kosoi 10HT with that of L. plantarum JCM1149T and L. rhamnosus GG. Although d-alanine or both d-alanine and carbohydrate residues were substituents of free hydroxyl groups in the polyglycerol phosphate structure in LTAs from strains JCM1149T and GG, d-alanine residues were not found in LTA from strain 10HT by 1H nuclear magnetic resonance (NMR) analysis. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) analysis of the glycolipid structure of LTA revealed that LTA from strain 10HT contained dihexosyl glycerol, whereas trihexosyl glycerol was detected in LTAs from other strains. These structural differences may be related to differences in IgA-inducing activity. IMPORTANCE The components of lactic acid bacteria that exert immunostimulatory effects are of increasing interest for therapeutic and prophylactic options, such as alternatives to antibiotics, cognitive enhancements, and vaccine adjuvants. LTAs act as immunostimulatory molecules in the host innate immune system by interacting with pattern recognition receptors. However, as LTA structures differ among species, detailed knowledge of the structure-function relationship for immunostimulatory effects is required. Comparisons of the IgA-inducing activity of LTAs have demonstrated that LTAs from the genus Apilactobacillus possess distinctive activities to stimulate mucosal immunity. The first analysis of the LTA structure from the genus Apilactobacillus suggests that it differs from structures of LTAs of related species of lactic acid bacteria. This knowledge is expected to aid in the development of functional foods containing lactic acid bacteria and pharmaceutical applications of immunostimulatory molecules from lactic acid bacteria.

DOI： 10.1128/aem.00190-22

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Quantifying proliferative virus particles is one of the most important experimental procedures in virology. Compared with classical overlay materials, newly developed cellulose derivatives enable a plaque-forming assay to produce countable clear plaques easily. HEp-2 cells are widely used in plaque assays for human respiratory syncytial virus (RSV). It is crucial to use an overlay material to keep HEp-2 cell proliferation and prevent RSV particles from spreading over the fluid. Among four cellulose derivatives, carboxymethyl cellulose sodium salt (CMC), hydroxypropyl methylcellulose (HPMC), microcrystalline cellulose (MCC), and hydroxyethyl cellulose (HEC), we found that HPMC was the optimal overlay material because HPMC maintained HEp-2 cell proliferation and RSV infectivity. Although MCC was unsuitable for RSV, it assisted the plaque-forming by human metapneumovirus in TMPRSS2-expressing cells. Therefore, depending on the cells and viruses, it is necessary to use different overlay materials at varying concentrations.

DOI： 10.1016/j.jviromet.2022.114528

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

The total synthesis of the depsipeptide natural product plusbacin A3 (1) utilizing solid-phase peptide synthesis (SPPS) was disclosed. A 3-hydroxy-proline derivative compatible with Fmoc SPPS was prepared by a diastereoselective Joullié-Ugi three-component reaction (JU-3CR)/hydrolysis sequence. After peptide elongation on the solid support, cleavage of the peptide from the resin, followed by macrolactamization and global deprotection, gave plusbacin A3 (1).

DOI： 10.1021/acs.orglett.2c00667

PubMed

researchmap

Language：English  

DOI： 10.1016/j.bmc.2022.116689

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: Eradication treatment for Helicobacter pylori gastritis is covered by national health insurance since 2013 in Japan. However, eradication failure due to the increase of antimicrobial resistance has become a serious problem. The present study aims to establish a reference panel of Japanese H. pylori strains for antimicrobial susceptibility testing. METHOD: A total of 28 strains were collected from 4 medical facilities in Japan. Antimicrobial susceptibility tests (ASTs) to clarithromycin (CLR), amoxicillin (AMX), and metronidazole (MNZ), were used to select standard reference strains. Complete genome sequences were also determined. RESULTS: Three H. pylori strains (JSHR3, JSHR6 and JSHR31) were selected as standard reference strains by the Japanese Society for Helicobacter Research (JSHR). The minimum inhibitory concentrations (MICs) of the antibiotics against these 3 strains by agar dilution method with Brucella-based horse-serum-containing agar medium were as follows: JSHR3 (CLR 16 μg/ml, AMX 0.032 μg/ml and MNZ 4 μg/ml), JSHR6 (CLR 0.016 μg/ml, AMX 0.032 μg/ml and MNZ 4 μg/ml), and JSHR31 (CLR 16 μg/ml, AMX 1 μg/ml and MNZ 64 μg/ml). CONCLUSIONS: A reference panel of H. pylori JSHR strains was established. The panel consisted of JSHR6, which was antibiotic-susceptible, JSHR3, which was CLR-resistant, and JSHR31, which was multi-resistant. This reference panel will be essential for standardized ASTs before the optimal drugs are selected for eradication treatment.

DOI： 10.1111/hel.12874

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND/AIM: Smell and taste disorders are among the most common symptoms of COVID-19. However, the relationship between smell and taste disorders and systemic symptoms is not fully understood in Japan. PATIENTS AND METHODS: Questionnaires were mailed to 105 of 111 COVID-19 patients who were hospitalized at our hospital between March and July 2020 in Japan. RESULTS: A total of 74 patients (response rate: 70.5%) completed the survey. Of these, six patients (8.1%) presented with smell disorders only, 16 (21.6%) presented with taste disorders only, and 17 (23.0%) presented with both smell and taste disorders. The mean Visual Analog Scale for smell and taste was 0.5 and 20, respectively, at the time of the most severe symptoms. CONCLUSION: Among COVID-19 patients in Japan, smell and taste disorders are often followed by fever and may not be the first symptoms. Sense of smell is particularly impaired. These symptoms often improve, although they sometimes persist for a long time as sequelae.

DOI： 10.21873/invivo.12781

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Selected lactic acid bacteria can stimulate macrophages and dendritic cells to secrete IL-12, which plays a key role in activating innate and cellular immunity. In this study, we investigated the roles of cell wall teichoic acids (WTAs) displayed on whole intact cell walls (ICWs) of Lactiplantibacillus plantarum in activation of mouse macrophages. ICWs were prepared from whole bacterial cells of several lactobacilli without physical disruption, and thus retaining the overall shapes of the bacteria. WTA-displaying ICWs of several L. plantarum strains, but not WTA-lacking ICWs of strains of other lactobacilli, elicited IL-12 secretion from mouse bone marrow-derived macrophages (BMMs) and mouse macrophage-like J774.1 cells. The ability of the ICWs of L. plantarum to induce IL-12 secretion was abolished by selective chemical elimination of WTAs from ICWs, but was preserved by selective removal of cell wall glycopolymers other than WTAs. BMMs prepared from TLR2- or TLR4-deficient mouse could secret IL-12 upon stimulation with ICWs of L. plantarum and a MyD88 dimerization inhibitor did not affect ICW-mediated IL-12 secretion. WTA-displaying ICWs, but not WTA-lacking ICWs, were ingested in the cells within 30 min. Treatment with inhibitors of actin polymerization abolished IL-12 secretion in response to ICW stimulation and diminished ingestion of ICWs. When overall shapes of ICWs of L. plantarum were physically disrupted, the disrupted ICWs (DCWs) failed to induce IL-12 secretion. However, DCWs and soluble WTAs inhibited ICW-mediated IL-12 secretion from macrophages. Taken together, these results show that WTA-displaying ICWs of L. plantarum can elicit IL-12 production from macrophages via actin-dependent phagocytosis but TLR2 signaling axis independent pathway. WTAs displayed on ICWs are key molecules in the elicitation of IL-12 secretion, and the sizes and shapes of the ICWs have an impact on actin remodeling and subsequent IL-12 production.

DOI： 10.3389/fmicb.2022.986396

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Transmission of colistin-resistant Enterobacterales from companion animals to humans poses a clinical risk as colistin is a last-line antimicrobial agent for treatment of multidrug-resistant Gram-negative bacteria including Enterobacterales. In this study, we investigated the colistin susceptibility of 285 Enterobacterales (including 140 Escherichia coli, 86 Klebsiella spp., and 59 Enterobacter spp.) isolated from companion animals in Japan. We further characterized colistin-resistant isolates by multilocus sequence typing (MLST), phylogenetic analysis of hsp60 sequences, and population analysis profiling, to evaluate the potential clinical risk of companion animal-derived colistin-resistant Enterobacterales to humans in line with the One Health approach. All E. coli isolates were susceptible to colistin, and only one Klebsiella spp. isolate (1.2%, 1/86 isolates) was colistin resistant. Enterobacter spp. isolates were frequently colistin resistant (20.3%, 12/59 isolates). In colistin-resistant Enterobacter spp., all except one isolate exhibited colistin heteroresistance by population analysis profiling. These colistin-heteroresistant isolates belonged to clusters I, II, IV, VIII, and XII based on hsp60 phylogeny. MLST analysis revealed that 12 colistin-resistant Enterobacter spp. belonged to the Enterobacter cloacae complex; five Enterobacter kobei (four ST591 and one ST1577), three Enterobacter asburiae (one ST562 and two ST1578), two Enterobacter roggenkampii (ST606 and ST1576), and Enterobacter hormaechei (ST1579) and E. cloacae (ST765) (each one strain). Forty-two percent of the colistin-resistant E. cloacae complex isolates (predominantly ST562 and ST591) belonged to lineages with human clinical isolates. Four E. kobei ST591 isolates were resistant to third-generation cephalosporines, aminoglycosides, and fluroquinolones but remained susceptible to carbapenems. In conclusion, our study is the first to our knowledge to report the frequent isolation of the colistin-resistant E. cloacae complex from companion animals. Furthermore, a subset of isolates belonged to human-associated lineages with resistance to multiple classes of antibiotics. These data warrant monitoring carriage of the colistin-resistant E. cloacae complex in companion animals as part of a domestic infection control procedure in line with the One Health approach.

DOI： 10.3389/fcimb.2022.946841

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Muraymycins and caprazamycins are strong inhibitors of MraY, which is responsible for peptidoglycan biosynthesis. Although they are promising antibacterial agents with a novel mode of action, their chemical structures are rather complex. This study investigated the simplification of these natural products by structure-based drug design, synthesis, and biological evaluation. We developed a simplified rigid scaffold with an arylalkyne moiety, which shows sub-micromolar MraY inhibitory activity. The scaffold is suitable for further investigating the structure-activity relationship by virtue of our synthetic strategy, where the substituent of interest is installed in the last stage of synthesis. This scaffold shows the potential for further use in optimizing MraY inhibitory and antibacterial activities.

DOI： 10.1016/j.bmc.2021.116556

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

An increase in human and veterinary fluoroquinolone-resistant Escherichia coli is a global concern. In this study, we isolated fluoroquinolone-resistant E. coli isolates from companion animals and characterized them using molecular epidemiological analysis, multiplex polymerase chain reaction to detect E. coli ST131 and CTX-M type extended-spectrum β-lactamases (ESBL), and multi-locus sequence typing analysis. Using plain-CHROMagar ECC, 101 E. coli isolates were isolated from 34 rectal swabs of dogs and cats. The prevalence of resistance to fluoroquinolone and cefotaxime was 27.7% and 24.8%, respectively. The prevalence of fluoroquinolone-resistant isolates (89.3%) was higher when CHROMagar ECC with CHROMagar ESBL supplement was used for E. coli isolation. The prevalence of cefotaxime resistance was also higher (76.1%) when 1 mg/L of ciprofloxacin-containing CHROMagar ECC was used for isolation. The cefotaxime-resistant isolates possessed CTX-M type β-lactamase genes (CTX-M-14, CTX-M-15, or CTX-M-27). Seventy-five percent of fluoroquinolone-resistant isolates were sequence types ST131, ST10, ST1193, ST38, or ST648, which are associated with extensive spread in human clinical settings. In addition, we isolated three common fluoroquinolone-resistant E. coli lineages (ST131 clade C1-M-27, C1-nM27 and ST2380) from dogs and their respective owners. These observations suggest that companion animals can harbor fluoroquinolone-resistant and/or ESBL-producing E. coli, in their rectums, and that transmission of these isolates to their owners can occur.

DOI： 10.3390/antibiotics10121463

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Diabetes mellitus is a chronic metabolic disease characterized by hyperglycemia and glucosuria, and is a risk factor for Candida infections. To reveal the potential effects of glucosuria on Candida spp., we investigated their growth and antifungal susceptibilities in normal human urine to which glucose was added. The viable cell numbers of Candida spp. were more than 10 fold higher in the urine added 3000 mg/dL glucose than in plain urine. In antifungal susceptibility, more than 80% of Candida albicans clinical isolates increased minimum inhibitory concentrations of azoles and 5-fluorocytosine with the addition of glucose, and exceeded their breakpoints. In most of the C. albicans clinical isolates, the mRNA expression of the azole resistance genes ERG11, CDR1, CDR2, and MDR1 in the presence of glucose in urine. These observations provide valuable information about the clinical course and therapeutic effects of azoles against C. albicans infections in patients with diabetes mellitus and hyperglucosuria.

DOI： 10.1016/j.diagmicrobio.2021.115556

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

OBJECTIVES: Fluoroquinolone (FQ)- and third-generation cephalosporin-resistant Escherichia coli are increasing in Japan. In the early 2000s, the FQ-resistant E. coli clone ST131 increased in clinical settings worldwide. It frequently produces extended-spectrum β-lactamases (ESBLs) such as CTX-M. This study aimed to explore the characteristics of FQ-resistant E. coli isolated in Japan during 2008-2009 and 2020. METHODS: We compared FQ-resistant E. coli clinical isolates from urine samples collected in 2020 (151 isolates) with a FQ-resistant E. coli collection isolated in 2008-2009 (42 isolates). Identification of E. coli ST131 clades and blaCTX-M were determined by multiplex PCR. Sequence types of non-ST131 isolates were determined by whole-genome sequencing. RESULTS: Although the prevalence of ST131 was comparable in 2020 (74.2%) and 2008-2009 (78.6%), the subclades differed during the two time periods (C1-nM27: 40.2% in 2008-2009 vs. 78.8% in 2020; C1-M27: 32.1% in 2008-2009 vs. 9.1% in 2020). The incidence of blaCTX-M among ST131 isolates increased from 27.3% in 2008-2009 to 64.3% in 2020. blaCTX-M was found in 80.6% and 93.8% of C1-M27 and C2 in 2020, respectively, and blaCTX-M possession in C1-nM27 increased from 19.2% in 2008-2009 to 40% in 2020. FQ-resistant ST1193 was detected only in 2020 (17.9% of 151 isolates, of which 14.8% possessed blaCTX-M). CONCLUSION: Increased resistance of E. coli to FQs and third-generation cephalosporins in Japan can be attributed to the accumulation of blaCTX-M in C1-nM27 and the increase of C1-M27 and C2 clades with high blaCTX-M possession, alongside the spread of ST1193.

DOI： 10.1016/j.jgar.2021.08.015

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

The complete genome sequence of mcr-10-possessing Enterobacter roggenkampii En37, isolated from a dog in Japan, was determined. mcr-10 was located on a 70,277-bp IncFIB plasmid without any additional antimicrobial resistance genes.

DOI： 10.1128/MRA.00426-21

PubMed

researchmap

Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Lactobacillus gasseri and Lactobacillus paragasseri are human commensal lactobacilli that are candidates for probiotic application. Knowledge of their oligosaccharide metabolic properties is valuable for synbiotic application. The present study characterized oligosaccharide metabolic systems and their impact on lipoteichoic acid (LTA) production in the two organisms, i.e., L. gasseri JCM 1131T and L. paragasseri JCM 11657. The two strains grew well in medium with glucose but poorly in medium with raffinose, and growth rates in medium with kestose differed between the strains. Oligosaccharide metabolism markedly influenced their LTA production, and apparent molecular size of LTA in electrophoresis recovered from cells cultured with glucose and kestose differed from that from cells cultured with raffinose in the strains. On the other hand, more than 15-fold more LTA was observed in the L. gasseri cells cultured with raffinose when compared with glucose or kestose after incubation for 15 h. Transcriptome analysis identified glycoside hydrolase family 32 enzyme as a potential kestose hydrolysis enzyme in the two strains. Transcriptomic levels of multiple genes in the dlt operon, involved in D-alanine substitution of LTA, were lower in cells cultured with raffinose than in those cultured with kestose or glucose. This suggested that the different sizes of LTA observed among the carbohydrates tested were partly due to different levels of alanylation of LTA. The present study indicates that available oligosaccharide has the impact on the LTA production of the industrially important lactobacilli, which might influence their probiotic properties.

DOI： 10.3390/microorganisms9081590

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Intrauterine infection is one of the most important causes of maternal death. In perinatal emergency, we often miss an opportunity to obtain culture specimens. In this study, we tried to examine whether we investigated whether bacteria causing infection can be detected from a formalin-fixed paraffin-embedded (FFPE) placental specimen. We examined the placenta from a maternal invasive infection that resulted in infectious abortion at 18 weeks of gestation. The case was diagnosed by acute fever and abdominal pain, and the patient was cured after 3 weeks of intensive antimicrobial treatment. Four Streptococcus pyogenes strains were isolated from vaginal fluid and blood cultures of the patient. All of the strain types were emm1/ST28. We amplified the V1-V2 region of 16S rRNA from an FFPE placental specimen and sequencing was performed using a next-generation sequencer (NGS). Taxonomic analysis was then performed for sequenced data. We succeeded in detecting causative pathogens from the FFPE placenta: 69.1% of the predominantly identified bacteria were S. pyogenes and other small populations of bacteria were detected. Our results revealed the utility of NGS for 16S rRNA analysis of an FFPE placenta. This method may reveal previous perinatal invasive infections of unknown origin retrospectively.

DOI： 10.1007/s00795-021-00298-2

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

We report the complete genome sequence of the mcr-9-possessing strain Enterobacter asburiae En30, isolated from a cat in Japan. The genome sequence was obtained by using long- and short-read sequencing.

DOI： 10.1128/MRA.00281-21

PubMed

researchmap

Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.nut.2020.111093

researchmap

Publishing type：Research paper (scientific journal)   Publisher：American Society for Microbiology  

The emergence of multidrug resistance in pathogens such as <named-content content-type="genus-species">Klebsiella pneumoniae</named-content> is of great clinical concern. Antimicrobial resistance sometimes arises during the course of an infection.

DOI： 10.1128/mbio.01954-20

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

INTRODUCTION: Eradication of asymptomatic bacteriuria (ASB) before urological procedures is important to reduce the risk for infectious complications after surgery. However, the appropriate regimen for antimicrobial treatment has not been fully determined. We experienced continuous (over 10 months) isolation of extended spectrum β-lactamase (ESBL)-producing fluoroquinolone-resistant Escherichia coli from urine of an asymptomatic patient. The four isolates obtained (SMESC1 to 4) were international high-risk clones of O25b:H4-ST131-H30R, and originated from one strain, as revealed by the whole genome sequences. Although the patient received meropenem (MEPM) and fosfomycin (FOM), to which the strains were susceptible before the urological procedures, they could not be eradicated. METHODS: To explore the reason for the continuous isolation even after MEPM and FOM administration, antimicrobial killing of adherent and/or intracellular bacterial communities (IBC) formed by coculture of the E. coli cells and T24 bladder epithelial cells were examined. RESULTS: FOM and levofloxacin did not decrease viable E. coli cells compared with gentamicin. MEPM partly decreased them, and sitafloxacin (STFX) decreased them most potently. These observations indicate that E. coli can survive in the urinary tract under antimicrobial administration, and some antimicrobials such as FOM and MEPM cannot eradicate E. coli in uroepithelial cells. Adhesion on urinary epithelial cells and/or IBC formation might result in continuous isolation from the urinary tract and recurrence of ASB and urinary tract infections. CONCLUSIONS: The present study suggests that STFX is a promising optional agent for the eradication of ESBL-producing fluoroquinolone-resistant E. coli in the urinary tract before urological procedures.

DOI： 10.1016/j.jiac.2020.07.009

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

We report the complete genome sequence of Escherichia coli strain HUE1, isolated from the urinary catheter of a female patient, showing fluoroquinolone resistance without quinolone resistance-determining region mutations. To facilitate the exploration of the molecular characteristics of HUE1, the whole genome was sequenced using long- and short-read platforms.

DOI： 10.1128/MRA.01135-20

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

The synthesis and biological evaluation of analogues of uridylpeptide antibiotics were described, and the molecular interaction between the 3'-hydroxy analogue of mureidomycin A (3'-hydroxymureidomycin A) and its target enzyme, phospho-MurNAc-pentapeptide transferase (MraY), was analyzed in detail. The structure-activity relationship (SAR) involving MraY inhibition suggests that the side chain at the urea-dipeptide moiety does not affect the MraY inhibition. However, the anti-Pseudomonas aeruginosa activity is in great contrast and the urea-dipeptide motif is a key contributor. It is also suggested that the nucleoside peptide permease NppA1A2BCD is responsible for the transport of 3'-hydroxymureidomycin A into the cytoplasm. A systematic SAR analysis of the urea-dipeptide moiety of 3'-hydroxymureidomycin A was further conducted and the antibacterial activity was determined. This study provides a guide for the rational design of analogues based on uridylpeptide antibiotics.

DOI： 10.1021/acs.jmedchem.0c00973

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: Treatment of VRE is of clinical concern. While certain numbers of vanD-type VRE have been isolated, only two vanD5-harbouring Enterococcus faecium isolates have been reported in Canada and Japan. METHODS: We report the isolation of vanD5-type E. faecium and the first ever determination of the whole-genome sequence to investigate the possible mechanisms of the acquisition of the vanD5 gene cluster in E. faecium. RESULTS: Two vanD5-harbouring vancomycin-resistant E. faecium were isolated from the skin (SMVRE19) and faeces (SMVRE20) of a patient with a skin ulcer in Japan. The isolates exhibited vancomycin and teicoplanin MIC values of 128 mg/L, whilst the previous isolates of vanD5-harbouring E. faecium were only resistant to vancomycin. SMVRE19 and SMVRE20 were clones related to ST18, which is also seen in vanA- and vanB-type VRE. These isolates harboured an insertion element, ISEfm1, in the ddl gene, similar to a previously described teicoplanin-resistant vanD3-type E. faecium. The vanD5 gene cluster was integrated into the SMVRE20 chromosome as a part of a large genomic island (approximately 127 kb), similar to other recently spreading vanD variants in the Netherlands. The genomic island shared the greatest similarity with a part of the Blautia coccoides genome sequence, except for the region surrounding the vanD gene cluster. CONCLUSIONS: This study reports that emergence of vancomycin- and teicoplanin-resistant vanD5-type E. faecium occurred via acquisition of the vanD5 cluster and ISEfm1 insertion into ddl. Considering the genetic similarity between the various VRE strains, the current study should serve as a warning against the spread of vanD5-type VRE.

DOI： 10.1093/jac/dkaa220

PubMed

researchmap

Language：English  

Campylobacter upsaliensis is an enteropathogenic bacterium in animals, and is also rarely isolated from humans, where it can cause enteritis and bacteremia. This report describes the first case of isolation of C. upsaliensis from an infected giant hepatic cyst. This bacterium could not be cultured from abscess punctuate in a usual Campylobacter-selection medium (charcoal cefoperazone deoxycholate agar medium), because of high concentration of cefoperazone as a selection agent. It could not identified by matrix-assisted laser desorption ionization-time of flight mass spectrum. Rather, it was identified as C. upsaliensis by whole genome sequencing, including by multilocus sequence typing.

DOI： 10.1016/j.jiac.2020.02.015

PubMed

researchmap

Language：English  

INTRODUCTION: Tazobactam-piperacillin (TZP) is a mixture of a broad-spectrum penicillin and an irreversible β-lactamase inhibitor. TZP is effective against Gram-negative bacteria that produce extended-spectrum β-lactamases, and it is used as a first-line or second-line drug to treat serious infections. METHODS: This study identified three TZP-resistant and two TZP-intermediate strains among 514 clinical isolates of Escherichia coli. RESULTS: These five isolates possessed one or more β-lactamase genes, blaTEM-1, blaCTX-M-2, blaCTX-M-14, and/or blaCMY-8. The expression levels of β-lactamase genes and acrAB genes in the strains were examined by using real-time reverse transcription PCR. The total enzymatic piperacillin-degrading activity in cells was determined. Two TZP-resistance mechanisms were identified: hyperproduction of TEM-1 in the two resistant strains; and simultaneous high production of β-lactamase and efflux pump AcrAB in the two TZP-intermediate isolates. The latter are an international high-risk clone O25b:H4-ST131-H30R. CONCLUSION: TZP resistance is still rare in clinical isolates of E. coli. However, resistance can develop on high production and/or combinations of known antimicrobial resistance mechanisms in different ways.

DOI： 10.1016/j.ijantimicag.2020.105919

PubMed

researchmap

Language：English  

Haemophilus influenzae is a pathogenic bacterium that causes respiratory and otolaryngological infections. The increasing prevalence of β-lactamase-negative high-level ampicillin-resistant H. influenzae (high-BLNAR) is a clinical concern. Fluoroquinolones are alternative agents to β-lactams. However, the emergence and increasing prevalence of fluoroquinolone-resistant H. influenzae have been reported. The current risk of fluoroquinolone resistance in H. influenzae (especially in high-BLNAR) has not yet been evaluated. Here, we examined the development of fluoroquinolone resistance in fluoroquinolone-susceptible clinical H. influenzae isolates in vitro during passaging in the presence of moxifloxacin (from 0.03 to 128 mg/liter). Twenty-nine isolates were examined. Seventeen isolates (58.6%) showed reduced moxifloxacin susceptibility, and 10 of these 17 isolates (34.5% of all isolates) exceeded the Clinical and Laboratory Standards Institute breakpoint for moxifloxacin (MIC of >1 mg/liter) after repeat cultivation on moxifloxacin-containing agar. Seven of these ten isolates were high-BLNAR and represented multiple lineages. We identified 56 novel mutations in 45 genes induced during the development of fluoroquinolone resistance, except the defined quinolone resistance-determining regions (Ser84Leu and Asp88Tyr/Gly/Asn in GyrA and Gly82Asp, Ser84Arg, and Glu88Lys in ParC). Glu153Leu and ΔGlu606 in GyrA, Ser467Tyr and Glu469Asp in GyrB, and ompP2 mutations were novel mutations contributing to fluoroquinolone resistance in H. influenzae In conclusion, H. influenzae clinical isolates from multiple lineages can acquire fluoroquinolone resistance by multiple novel mutations. The higher rate of derivation of fluoroquinolone-resistant H. influenzae from high-BLNAR than β-lactamase-negative ampicillin-susceptible isolates (P = 0.01) raises the possibility of the emergence and spread of fluoroquinolone-resistant high-BLNAR in the clinical setting.

DOI： 10.1128/AAC.01500-19

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Escherichia coli (E. coli) causes urinary tract infections, pneumonia, surgical site infections, and bloodstream infections and is the important pathogen for both community-acquired and healthcare-associated infections. To investigate the clonality of E. coli is important for infection control and prevention. We aimed to investigate the clonality of clinical E. coli isolates using Cica Geneus E. coli polymerase chain reaction (PCR)-based open-reading frame typing (POT) KIT and clarify the clinical usefulness of this kit. About 124 E. coli isolates obtained from inpatients at Sapporo Medical University Hospital were used. The POT method was used to classify 124 clinical isolates into 87 POT numbers. In addition to the clonality, it was possible to obtain additional information that 20 of the 124 isolates were extended-spectrum β-lactamase (ESBL) producing E. coli (5 isolates of CTX-M-1 group and 15 isolates of CTX-M-9 group) and 13 were sequence type (ST) 131 clone. Furthermore, when these ESBL-producing 20 isolates were compared with pulsed-field gel electrophoresis (PFGE) or multilocus sequence typing (MLST), Simpson's index of diversity was 0.968 in POT method, 0.979 in PFGE, and 0.584 in MLST. POT method had an analytical power similar to that of PFGE. In conclusion, attention should be paid to the difference in the interpretation of the results between the POT method and the PFGE, but POT method may be useful to timely monitor the spread of E. coli in medical facilities.

DOI： 10.1016/j.jiac.2019.06.014

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Acetic acid treatment [98% (v/v), 100 °C, 3 h] was proposed as a new method for degrading the glycerophosphate polymer moiety of Gram-positive bacterial lipoteichoic acid. We demonstrated that this method resulted in partial O-acetylation on the carbohydrate residues of the anchor glycolipid. Hence, the acetic acid treatment is not suitable for the chemical structural analysis of lipoteichoic acid.

DOI： 10.1016/j.mimet.2019.105726

PubMed

researchmap

Language：English  

Neisseria gonorrhoeae is a principal pathogen for sexually transmitted infections, especially for male urethritis. Currently, the prevalence of multidrug resistance is increasing. Carbapenems are broad-spectrum antimicrobials that are widely used in the clinical setting, especially for multidrug-resistant Gram-negative bacteria. However, susceptibility to carbapenems has not been well evaluated for cephalosporin-resistant N. gonorrhoeae isolates. In this study, we determined the susceptibility to a series of carbapenems (meropenem, imipenem, doripenem, and biapenem) and faropenem against cephalosporin-resistant (resistant to cefixime, but susceptible to ceftriaxone) and cephalosporin-susceptible N. gonorrhoeae clinical isolates. The gene mutations associated with β-lactam resistance were evaluated. All cephalosporin-resistant N. gonorrhoeae isolates possessed mosaic mutation alleles in penA (NG-STAR penA-10.001, 27.001, or 108.001). They exhibited a low minimum inhibitory concentration (MIC) (≤0.125 mg/L) for meropenem and markedly high MICs (0.5-2 mg/L) for other carbapenems and faropenem. The strongest association was observed between the mosaic alleles in penA and decreased susceptibility to carbapenems and faropenem compared with mutations in mtrR, porB, and ponA. These results suggest that meropenem may serve as an alternative therapeutic agent for cephalosporin-resistant N. gonorrhoeae with a mosaic allele in penA, whereas other carbapenems and faropenem may be ineffective.

DOI： 10.1089/mdr.2018.0263

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: The prevalence of antibodies against M-type anti-phospholipase A2 receptor (PLA2R) was reported to be ~ 70-80% in early studies on idiopathic membranous nephropathy (iMN) cohorts from Western countries, China, and Korea, and ~ 50% in recent studies on two Japanese iMN cohorts. METHODS: We developed an in-house enzyme-linked immunosorbent assay (ELISA) for the detection of anti-PLA2R antibodies, and examined sera from 217 patients with iMN, 22 patients with secondary MN (sMN), and 50 healthy individuals. All patients and healthy individuals were Japanese. The relationships between levels of anti-PLA2R antibodies and clinical parameters were analyzed. Serum samples were also tested using a standardized commercial ELISA (Euroimmun, Germany). RESULTS: In our ELISA, OD values greater than the mean + 3 standard deviation of healthy subjects were considered to be positive for anti-PLA2R antibodies. Of the patients with iMN, 33.6% (73/217) were positive, but all sMN patients were negative. Our ELISA and the Euroimmun ELISA had a high concordance (93.5%). The proportion of patients with nephrotic syndrome was significantly higher in anti-PLA2R antibody-positive patients than in antibody-negative patients (65.8 vs. 37.5%, P < 0.001). Levels of anti-PLA2R antibodies were significantly correlated with levels of urinary protein and serum albumin (P = 0.004 and P < 0.001, respectively). CONCLUSIONS: The prevalence of anti-PLA2R antibodies in our Japanese iMN cohort was lower than that in the previous studies from other countries and other Japanese institutes. The low prevalence of antibodies may be related with the characteristics of enrolled patients with mild proteinuria and undetectable antibody levels.

DOI： 10.1007/s10157-019-01712-x

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

researchmap

Language：Japanese  

Other Link： https://search.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2018&ichushi_jid=J05942&link_issn=&doc_id=20181126320008&doc_link_id=%2Ffb1endto%2F2018%2F002100%2F009%2F0035-0037%26dl%3D0&url=https%3A%2F%2Fwww.medicalonline.jp%2Fjamas.php%3FGoodsID%3D%2Ffb1endto%2F2018%2F002100%2F009%2F0035-0037%26dl%3D0&type=MedicalOnline&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00004_2.gif

Ichushi

J-GLOBAL

researchmap

Language：Japanese   Publisher：緑膿菌感染症研究会  

Ichushi

J-GLOBAL

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

β-Lactam-resistant Haemophilus influenzae is a clinical concern. A high prevalence (>40%) of β-lactamase-negative high-level ampicillin-resistant H. influenzae (high-BLNAR) isolates in Japan has been reported. However, the reasons for the expansion are unknown. High-BLNAR strains possess an amino acid substitution, either Asn526Lys (group III) or Arg517His (group III-like) in addition to Ser385Thr, in penicillin-binding protein 3 (PBP3). To determine the current prevalence of high-BLNAR strains and the mechanisms behind their expansion in Japan, their prevalence, PBP3 types, multilocus sequence types, and susceptibilities to quinolones approved in Japan as alternatives were determined. Sixty percent of H. influenzae clinical isolates (62/104 isolates) were β-lactamase-negative ampicillin-resistant H. influenzae (BLNAR) strains. Among BLNAR isolates, 92% (57/62 isolates) were high-BLNAR strains. Most isolates were classified as belonging to group III, which contained many genotypes (11 PBP3 types and 25 sequence types). These results indicated that the expansion of high-BLNAR isolates was multiclonal and such strains are still predominant in Japanese clinical settings. One high-BLNAR isolate harbored the novel amino acid substitution Asn526Met in addition to Ser385Thr in PBP3, suggesting a new group (group IV). No quinolone-resistant H. influenzae isolates were identified. The MICs for the quinolones (moxifloxacin, garenoxacin, and tosufloxacin) were similar to that for levofloxacin, whereas sitafloxacin exhibited a lower MIC. However, we obtained 4 H. influenzae isolates with decreased quinolone susceptibility with the amino acid substitution Ser84Leu in GyrA, and 3 of those isolates were high-BLNAR isolates. In summary, this study shows that multiclonal high-BLNAR strains predominate in a Japanese university hospital. Isolates remain sensitive to quinolones, but vigilance is required to prevent the development of fluoroquinolone resistance in high-BLNAR strains.

DOI： 10.1128/AAC.00851-18

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Colistin is a last-line drug for multidrug-resistant Gram-negative bacteria. We previously reported four plasmid-mediated colistin resistance (mcr) gene-negative colistin-resistant Escherichia coli clinical isolates, including the major pathogenic and fluoroquinolone-resistant strains O25b:H4-ST131-H30Rx (isolates SRE34 and SRE44; MIC for colistin = 16 mg/liter), non-x (SME296; MIC = 8 mg/liter), and O18-ST416 (SME222; MIC = 4 mg/liter). In this study, we investigated the colistin resistance mechanism and identified novel amino acid substitutions or deletions in the PmrAB two-component system that activates eptA (encoding a phosphoethanolamine transferase) and arnT (encoding an undecaprenyl phosphate-alpha-4-amino-4-deoxy-l-arabinose arabinosyl transferase) in all colistin-resistant isolates. SRE34 possessed deletion Δ27-45 (LISVFWLWHESTEQIQLFE) in PmrB, SRE44 possessed substitution L105P in PmrA, and both SME222 and SME296 included substitution G206D in PmrB. Matrix-assisted laser desorption ionization-time of flight mass spectrometry revealed that lipid A is modified with phosphoethanolamine in all four isolates. Deletion of pmrAB decreased colistin MICs to 0.5 mg/liter and lowered eptA and arnT expression. Chromosomal replacement of mutated pmrA or pmrB in colistin-susceptible O25b:H4-ST131 strain SME98 (colistin MIC = 0.5 mg/liter) increased the colistin MIC to that of the respective parent colistin-resistant isolate. In addition, SME98 mutants in which pmrAB was replaced with mutated pmrAB showed no significant differences in bacterial growth and competition culture from the parent strain, except for the mutant with L105P in PmrA, whose growth was significantly suppressed in the presence of the parent strain. In conclusion, some O25b:H4-ST131 strains appear to acquire colistin resistance via phosphoethanolamine modification of lipid A through amino acid changes in PmrAB, and the amino acid changes in PmrB do not influence bacterial growth.

DOI： 10.1128/AAC.00864-18

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: Interstitial lung diseases (ILD) are severe respiratory diseases, and ILD patients are treated with corticosteroid and immunosuppressive agents. However, it is unclear whether these medications influence the response of pneumococcal vaccine. OBJECTIVES: We examined the immunogenicity of pneumococcal vaccines (PPSV23 and PCV13) in ILD patients undergoing immunosuppressive treatment. METHODS: ILD patients who were regularly followed at the outpatient clinic were enrolled. Sera were collected before and 4-8 weeks after vaccination. Serotype-specific immunoglobulin G (IgG) concentrations against pneumococcal serotype 19F were measured by ELISA. RESULTS: IgG concentrations to serotype 19F were increased in all groups in response to the vaccine. Both PCV13 and PPSV23 induced IgG concentrations in patients immunized for the first time. Response rates for the ILD group were comparable with those for the ILD group undergoing corticosteroid therapy. Only idiopathic pulmonary fibrosis patients undergoing immunosuppressive therapy had a significantly lower response.

DOI： 10.1016/j.vaccine.2018.06.062

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Multidrug-resistant Streptococcus pneumoniae strains were isolated from blood and sputum of a patient with disseminated intravascular coagulation in Sapporo city, Japan. These antibiograms were only susceptible to vancomycin, linezolid, daptomycin, some carbapenems, and some fluoroquinolones. Identical antibiograms, serotypes (19F), and sequence types (ST10017) suggested a shared origin of these isolates. Only one ST10017 strain has been isolated in the same city in Japan previously (2014), and the 2014 isolate is still susceptible to macrolides. The whole genome of the blood-derived isolate was sequenced. The strain harbored resistance mutations in parC, gyrA, pbp1a, pbp2a, pbp2b, and pbp2x, and harbored the resistance genes, ermB and tetM. The nucleotide sequences of parC and pbp2x genes of strain MDRSPN001 were clearly different from those of other S. pneumoniae strains and were similar to those of oral streptococci strains. These findings suggest that strain MDRSPN001 has been rapidly and drastically evolving multidrug resistance by gene replacement and accumulation of genes originating from other strains, such as oral streptococci, Streptococcus mitis.

DOI： 10.1016/j.jiac.2018.01.012

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jgar.2018.02.010

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Pseudomonas aeruginosa is an important etiological agent of opportunistic infections. Injectable colistin is available as a last-line treatment option for multidrug-resistant P. aeruginosa infections. When cells were inoculated at a high number, colistin-susceptible P. aeruginosa grew on agar medium containing colistin at a concentration 10-fold higher than the minimum inhibitory concentration without acquiring colistin resistance. This study examined the responsible mechanism for growth in the presence of a high concentration of colistin. Cell wash fluid derived from P. aeruginosa efficiently reduced colistin antimicrobial activity. This reduction was mediated by lipopolysaccharide (LPS) in the wash fluid. Extracellular LPS inhibited colistin activity more effectively than cell-bound LPS in fixed cells. Cell wash fluids from Escherichia coli and Acinetobacter baumannii also reduced colistin activity; however, they were less potent than those from P. aeruginosa. The amount of LPS in cell wash fluid from P. aeruginosa was approximately 10-fold higher than that in fluid from E. coli or A. baumannii. In conclusion, cell-free LPS derived from bacterial cells inhibited the antimicrobial activity of colistin, and this effect was greatest for P. aeruginosa. Thus, large amounts of broken and dead cells of P. aeruginosa at infection foci will reduce the effectiveness of colistin, even against cells that have not yet acquired resistance.

DOI： 10.1016/j.ijantimicag.2018.02.004

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

The plaque-forming assay is the standard technique for determining viral titer, and a critical measurement for investigating viral replication. However, this assay is highly dependent on experimental technique and conditions. In the case of human respiratory syncytial virus (RSV) in particular, it can be difficult to objectively confirm the accuracy of plaque-forming assay because the plaques made by RSV are often small and unclear. In recent studies, RT-qPCR methods have emerged as a supportive procedure for assessment of viral titer, yielding highly sensitive and reproducible results. In this report, we compare the viral replication, as determined by plaque-forming assay, and the copy numbers of RSV genes NS1, NS2, N, and F, as determined by RT-qPCR. Two real-time PCR systems, SYBR Green and TaqMan probe, gave highly similar results for measurement of copy numbers of RSV N genes of virus subgroups A. We determined the RSV gene copy numbers in the culture cell supernatant and cell lysate measured at various multiplicities of infection. We found that copy number of the RSV N gene in the culture supernatant and cell lysate was highly correlated with plaque-forming units. In conclusion, RT-qPCR measurement of RSV gene copy number was highly dependent on viral titer, and the detailed comparison between each gene copy number and virus titer should be useful and supportive in confirming RSV plaque-forming assay and virus dynamics. The technique may also be used to estimate the amount of RSV present in clinical specimens.

DOI： 10.1111/1348-0421.12563

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.ijantimicag.2017.11.010

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wageningen Academic Publishers  

DOI： 10.3920/BM2017.0124

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Invasive infection of multidrug-resistant Streptococcus pneumoniae is a serious clinical concern. Here, we report the complete genome sequence of a multidrug-resistant S. pneumoniae serotype 19F strain isolated from a patient with an invasive infection in Sapporo, Japan.

DOI： 10.1128/genomeA.01239-17

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/s41598-017-11481-w

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1186/s13568-017-0430-1

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1111/1348-0421.12490

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1111/1348-0421.12483

Web of Science

researchmap

Language：Japanese   Publisher：(公財)日本感染症医薬品協会  

Ichushi

researchmap

Language：Japanese   Publisher：(公財)日本感染症医薬品協会  

Ichushi

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.bbrc.2016.12.100

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/AAC.01654-16

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.bbrc.2016.12.133

Web of Science

researchmap

Language：Japanese  

J-GLOBAL

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1159/000449368

Web of Science

researchmap

Language：Japanese  

J-GLOBAL

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1155/2017/5470241

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3201/eid2212.161117

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.phrs.2016.07.033

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1371/journal.pone.0161793

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1089/vim.2016.0004

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1111/hel.12217

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/srep13738

Web of Science

researchmap

Language：Japanese   Publisher：顎顔面口腔育成研究会  

Ichushi

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1292/jvms.13-0144

Web of Science

researchmap

Publisher：3  

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1074/jbc.M114.553255

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1371/journal.pone.0096101

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jiac.2013.12.003

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1186/1471-2466-14-48

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1099/jmm.0.054676-0

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1159/000365880

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s00795-013-0024-1

Web of Science

researchmap

Language：English  

DOI： 10.1128/AEM.03100-13

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/jmv.23718

PubMed

researchmap

DOI： 10.1186/1465-9921-14-133

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1371/journal.pone.0070225

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s12192-013-0411-5

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/AEM.00243-13

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1111/hel.12011

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1155/2013/721306

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1292/jvms.12-0186

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Frontiers Research Foundation  

DOI： 10.3389/fmicb.2013.00125

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1159/000361011

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/JVI.01196-12

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/IAI.00345-12

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1159/000336129

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1155/2012/528568

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.virusres.2011.07.011

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/AAC.00532-11

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.virol.2011.03.010

Web of Science

researchmap

Language：Japanese  

J-GLOBAL

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1111/j.1574-6968.2010.02049.x

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/AAC.00110-10

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1089/jir.2009.0015

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1074/jbc.M109.074765

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/IAI.00903-09

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jneuroim.2009.10.009

Web of Science

researchmap

Language：Japanese  

J-GLOBAL

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.bbrc.2009.09.099

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.diagmicrobio.2009.05.006

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.virol.2009.06.026

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.ijid.2008.09.017

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/CVI.00033-09

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: The pathological diagnosis of idiopathic interstitial pneumonias (IIP) by surgical lung biopsy is important for clinical decision-making. However, there is a need to use less invasive biomarkers to differentiate nonspecific interstitial pneumonia (NSIP) from other IIP such as usual interstitial pneumonia (UIP). Heat shock protein (HSP) 47, a collagen-specific molecular chaperone, is involved in the processing and/or secretion of procollagen. HSP47 is increased in various fibrotic diseases. We investigated the autoantibodies to HSP47 in IIPs. METHODS: We measured the serum levels of the autoantibodies to HSP47 in 38 patients with various forms of IIP [16 with idiopathic pulmonary fibrosis (IPF), 15 with idiopathic NSIP, 7 with cryptogenic organizing pneumonia (COP)] and 18 healthy volunteers. RESULTS: The serum levels of autoantibodies to HSP47 in patients with idiopathic NSIP were significantly higher than in patients with IPF (P < 0.01), COP (P < 0.05), and healthy volunteers (P < 0.05). In addition, those in fibrosing NSIP were significantly higher than those of cellular and fibrosing NSIP (p < 0.05). CONCLUSION: We found high levels of anti-HSP47 autoantibody titers in sera of patients with idiopathic fibrosing NSIP compared with other IIPs and healthy volunteers.

DOI： 10.1186/1471-2466-8-23

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1097/INF.0b013e31817d756e

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/JCM.00305-08

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1086/526784

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/JCM.01561-07

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1096/fj.07-8976com

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Japan  

DOI： 10.1007/s10156-007-0583-y

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Japan  

DOI： 10.1007/s10156-008-0604-5

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1111/j.1574-695X.2007.00288.x

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.virol.2006.11.002

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.cimid.2006.11.002

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1111/j.1574-695X.2006.00166.x

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Japan  

DOI： 10.1007/s10156-007-0528-5

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jns.2006.06.012

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/intimm/dxh399

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/jmv.20556

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jns.2005.10.009

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Japan  

DOI： 10.1007/s10156-006-0473-8

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.virol.2005.08.010

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.virol.2005.04.028

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/JCM.43.5.2246

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/JVI.79.7.4451-4459.2005

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jneuroim.2004.07.017

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/CDLI.11.5.969-976.2004

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/JVI.78.12.6282-6286.2004

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1074/jbc.M312490200

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/JVI.78.9.4591-4598.2004

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Japan  

DOI： 10.1007/s10156-004-0340-4

PubMed

researchmap

Language：Japanese  

J-GLOBAL

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1074/jbc.M305701200

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0006-291X(03)00352-8

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1038/sj.cdd.4401169

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0042-6822(02)00026-0

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/JVI.76.24.12683-12690.2002

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/JVI.76.24.12676-12682.2002

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1128/AAC.46.10.3311-3315.2002

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1046/j.1432-1327.2001.02393.x

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1006/viro.2001.0941

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1006/bbrc.2001.4764

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1006/bbrc.2000.4011

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1074/jbc.M005009200

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/glycob/10.7.701

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0378-1097(00)00102-6

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1046/j.1432-1327.2000.01157.x

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1074/jbc.274.52.37070

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/S0014-5793(99)01437-4

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1046/j.1432-1327.1999.00405.x

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN BIFIDUS FOUNDATION  

We have examined the responses of polymorphonuclear neutrophils (PMNs) and human umbilical vein endothelial cells (HUVEC) to <I>Helicobacter pylori</I> lipopolysaccharides (LPSs). High-antigenicity-polysaccharide-carrying smooth LPS and rough LPS from <I>H. pylori</I> were used for the experiments. PMN activation was determined by chemiluminescence response (CLR). The priming effect of patient's serum or IL-8 on the CLR was also examined. After stimulation of HUVEC with the LPSs, the supernatant was tested for IL-6, IL-8 and RANTES by ELISA. Direct induction of CLR was observed after the stimulation of <I>H. pylori</I> LPSs. Though the response was weak, enhancement occurred in response to high-antigenicity-polysaccharide-carrying smooth LPS by patient's serum against the LPS. IL-8 priming was also effective to enhance CLR, which was induced by <I>H. pylori</I> LPS. Following exposure to <I>H. pylori</I> LPSs, HUVEC secreted IL-6 and IL-8 but not RANTES. The enhanced secretion of both IL-6 and IL-8 occurred in a time-dependent manner. However, the cytokine-inducing ability of <I>H. pylori</I> LPSs is significantly lower than that of other Gram-negative bacteria such as <I>Escherichia coli</I> and <I>Campylobacter jejuni</I>. Structurally similar LPS from <I>Porphyromonas gingivalis</I> also showed weak potency. These results suggest that the ability of <I>H. pylori</I> LPSs is not directly effected to induce inflammation. However, an indirect effect of these LPSs, or continuous stimulation with these LPSs to endothelial cells, may relate to persistent infection.

DOI： 10.12938/bifidus1996.18.119

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1093/glycob/6.4.463

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/0928-8244(96)00010-7

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1083/jcb.133.2.469

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1099/13500872-142-2-289

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1006/bbrc.1996.0126

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/0378-1097(94)00329-7

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/0008-6215(94)80005-7

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1111/j.1432-1033.1992.tb16963.x

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1111/j.1432-1033.1990.tb19202.x

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

The human monoclonal antibody MH-4H7 recognizes the lipopolysaccharide outer core region of some Pseudomonas aeruginosa strains and in of some Pseudomonas aeruginosa strains and in particular strongly binds to strains of Lányi serotype 04. In this paper, we report that this monoclonal antibody also reacts with Escherichia coli O26 LPS. However, our results suggest that the previous reported immunological cross reaction between P. aeruginosa 04 and E. coli O26 strains (which was observed by using antisera against heat-stable antigens) is not due to the similarity of the O-polysaccharides.

PubMed

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1111/j.1432-1033.1987.tb13324.x

PubMed

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

PubMed

Web of Science

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

Language：Japanese   Publisher：(公社)日本化学療法学会  

Ichushi

researchmap

Language：Japanese   Publisher：日本感染症学会・日本化学療法学会  

Ichushi

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

Language：English   Publisher：日本細菌学会  

Ichushi

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

Language：Japanese  

J-GLOBAL

researchmap

Language：Japanese  

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：(株)医薬ジャーナル社  

Ichushi

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap