Publications

TitleAbstractYear(sorted ascending)
Filter
PMID
Filter
emergence of streptococcus suis serotype 9 infection in humans. 201526362754
assessment of maldi-tof ms as alternative tool for streptococcus suis identification.the accuracy of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (maldi-tof ms) for identifying streptococcus suis isolates obtained from pigs, wild animals, and humans was evaluated using a pcr-based identification assay as the gold standard. in addition, maldi-tof ms was compared with the commercial multi-tests rapid id 32 strep system. from the 129 s. suis isolates included in the study and identified by the molecular method, only 31 isolates (24.03%) had score val ...201526347858
virulence genotyping and population analysis of streptococcus suis serotype 2 isolates from china.streptococcus suis is one of the most important swine pathogens worldwide. in this study, a total of 22 virulence-related genes in 101 strains of s. suis serotype 2 (ss2) were detected by pcr, namely, mrp, epf, sly, fbps, rgg, ofs, srta, pgda, gapdh, iga, endod, ciarh, salkr, mann, purd, rgg, dppiv, neub, dlta, smu_61-like, spym3_0908 (permease) and the sspa gene. the distribution of virulence-related genes among isolates was visualized using bionumerics software to study similarities among the ...201526303637
catabolite control protein a has an important role in the metabolic regulation of streptococcus suis type 2 according to itraq-based quantitative proteomic analysis.the catabolite control protein a (ccpa) regulates the carbon metabolism in streptococcus suis type 2 and has pleiotropic regulatory functions in bacterial virulence and transcription. the present study systematically investigated ccpa activity in streptococcus suis type 2 using isobaric tag for relative and absolute quantification (itraq) liquid chromatography‑tandem mass spectrometry‑based proteomics. gene ontology and kyoto encyclopedia of genes and genomes analyses demonstrated that ccpa is a ...201526299628
[correlation between type iv secretion system component vird4 and virulence for streptococcus suis 2].in order to study the role of ss2 type iv secretion system vird4 in evasion of the host innate immune killing, we constructed a knockout mutant avird4. then we studied its biological activity and virulence.201526259489
msmk, an atpase, contributes to utilization of multiple carbohydrates and host colonization of streptococcus suis.acquisition and metabolism of carbohydrates are essential for host colonization and pathogenesis of bacterial pathogens. different bacteria can uptake different lines of carbohydrates via abc transporters, in which atpase subunits energize the transport though atp hydrolysis. some abc transporters possess their own atpases, while some share a common atpase. here we identified msmk, an atpase from streptococcus suis, an emerging zoonotic bacterium causing dead infections in pigs and humans. genet ...201526222651
[lytic phages and prophages of streptococcus suis--a review].streptococcus suis (s. suis) is an important zoonosis and pathogen that can carry prophages. in this review, we focus on the recent advances in our understanding of lytic phage and lysogenic phage of s. suis, including the morphology of s. suis lytic phage, the functions of lysin and terminase large subunit encoded by s. suis lytic phage, comparative genomics of s. suis prophages, lysogenic. conversion between s. suis lytic phage and prophage. furthermore, prospective evolution of interactions b ...201526211312
simultaneous detection of 33 streptococcus suis serotypes using the luminex xtag® assay™.we report the development and evaluation of a serotype-specific xtag luminex assay (ssa) that allows detection of the 33 serotypes of streptococcus suis (s. suis). this assay is based on wzy gene targets directly involved in the cps biosynthesis and can be completed 40 min post-pcr amplification. the assay correctly and specifically identified the serotype of all 209 isolates tested, in comparison with two serotyping multiplex pcr methods previously developed. the sensitivity was higher than tha ...201526210040
investigation into the role of catabolite control protein a in the metabolic regulation of streptococcus suis serotype 2 using gene expression profile analysis.catabolite control protein a (ccpa) serves a key function in the catabolism of streptococcus suis serotype 2 (s. suis 2) by affecting the biological function and metabolic regulatory mechanisms of this bacterium. the aim of the present study was to identify variations in ccpa expression in s. suis 2 using gene expression profile analysis. using sequencing and functional analysis, ccpa was demonstrated to play a regulatory role in the expression and regulation of virulence genes, carbon metabolis ...201526170923
toll-like receptor 4 confers inflammatory response to suilysin.streptococcus suis serotype 2 (ss2) is an emerging human pathogen worldwide. a large outbreak occurred in the summer of 2005 in china. serum samples from this outbreak revealed that levels of the main proinflammatory cytokines were significantly higher in patients with streptococcal toxic-shock-like syndrome (stsls) than in patients with meningitis only. however, the mechanism underlying the cytokine storm in stsls caused by ss2 remained unclear. in this study, we found that suilysin (sly) is th ...201526167160
streptococcus suis meningitis in the netherlands. 201526165610
the type ii histidine triad protein htpsc is a novel adhesion with the involvement of streptococcus suis virulence.streptococcal histidine triad proteins htps are widely distributed within the streptococcus genus. based on the phylogenetic relationship and domain composition, htps are classified into type i and type ii subfamilies. previous studies revealed that several pathogenic streptococci contain more than one htp gene. we found that the highly virulent strain of streptococcus suis 2 (s. suis 2), 05zyh33 encodes 3 htps, designated htpsa (previously described as htps), htpsb, and htpsc. among them, htpsc ...201526151575
molecular diagnostics and its-based phylogenic analysis of streptococcus suis serotype 2 in central vietnam.streptococcus suis (s. suis) serotype 2 has recently become the most prevalent cause of meningitis in adults in many areas of vietnam. this study provides data on s. suis molecular diagnosis in central vietnam using a real-time polymerase chain reaction (pcr) assay targeting the s. suis serotype 2 cps2j gene. additionally, 16s-23s rdna intragenic spacer (its)-based phylogenic analysis of strains isolated from cerebrospinal fluid (csf) in thua thien hue province, vietnam, is presented and discuss ...201526142672
the chromosomal sezat toxin-antitoxin system promotes the maintenance of the sspi-1 pathogenicity island in epidemic streptococcus suis.streptococcus suis has emerged as a causative agent of human meningitis and streptococcal toxic shock syndrome over the last years. the high pathogenicity of s. suis may be due in part to a laterally acquired pathogenicity island (renamed sspi-1), which can spontaneously excise and transfer to recipients. cells harboring excised sspi-1 can potentially lose this island if cell division occurs prior to its reintegration; however, attempts to cure sspi-1 from the host cells have been unsuccessful. ...201526138696
streptococcus suis sorption on agricultural soils: role of soil physico-chemical properties.understanding pathogen sorption on natural soil particles is crucial to protect public health from soilborne and waterborne diseases. sorption of pathogen streptococcus suis on 10 agricultural soils was examined, and its correlations with soil physico-chemical properties were also elucidated. s. suis sorption isotherms conformed to the linear equation, with partition coefficients (ks) ranging from 12.7 ml g(-1) to 100.1 ml g(-1). bacteria were observed to sorb on the external surfaces of soil ag ...201524968305
construction, characterization and evaluation of the protective efficacy of the streptococcus suis double mutant strain δsspep/δsspspc as a live vaccine candidate in mice.streptococcus suis serotype 2 (s. suis 2) causes sepsis and meningitis in piglets and humans, and results in one of the most serious bacterial diseases affecting the production of commercial pigs around the world. due to the failure of the current inactivated vaccine to protect against the disease, development of a new attenuated live vaccine against s. suis 2 by deleting essential virulence factors is urgently needed. we have previously reported the construction and characterization of an sspep ...201525220429
identification and characterization of the chromosomal yefm-yoeb toxin-antitoxin system of streptococcus suis.toxin-antitoxin (ta) systems are widely prevalent in the genomes of bacteria and archaea. these modules have been identified in escherichia coli and various other bacteria. however, their presence in the genome of streptococcus suis, an important zoonotic pathogen, has received little attention. in this study, we describe the identification and characterization of a type ii ta system, comprising the chromosomal yefm-yoeb locus of s. suis. the yefm-yoeb locus is present in the genome of most sero ...201526272287
cultural drivers and health-seeking behaviours that impact on the transmission of pig-associated zoonoses in lao people's democratic republic.pig rearing is an important income source in the lao people's democratic republic (pdr), with many smallholder farmers using traditional free-range pig production systems. despite the potentially significant health risks posed by pig production regarding pig-associated zoonoses, information on the sociocultural drivers of these zoonoses is significantly lacking. this review summarises the existing sociocultural knowledge on eight pig-associated zoonoses suspected to be endemic in southeast asia: ...201525973203
crystal structure and identification of two key amino acids involved in ai-2 production and biofilm formation in streptococcus suis luxs.streptococcus suis has emerged as an important zoonotic pathogen that causes meningitis, arthritis, septicemia and even sudden death in pigs and humans. quorum sensing is the signaling network for cell-to-cell communication that bacterial cells can use to monitor their own population density through production and exchange of signal molecules. s-ribosylhomocysteinase (luxs) is the key enzyme involved in the activated methyl cycle. autoinducer 2 (ai-2) is the adduct of borate and a ribose derivat ...201526484864
suicin 3908, a new lantibiotic produced by a strain of streptococcus suis serotype 2 isolated from a healthy carrier pig.while streptococcus suis serotype 2 is known to cause severe infections in pigs, it can also be isolated from the tonsils of healthy animals that do not develop infections. we hypothesized that s. suis strains in healthy carrier pigs may have the ability to produce bacteriocins, which may contribute to preventing infections by pathogenic s. suis strains. two of ten s. suis serotype 2 strains isolated from healthy carrier pigs exhibited antibacterial activity against pathogenic s. suis isolates. ...201525659110
trem-1 signaling promotes host defense during the early stage of infection with highly pathogenic streptococcus suis.infection with highly pathogenic streptococcus suis can cause septic shock, which is characterized by high levels of inflammatory cytokines and a high mortality rate. our previous study indicated that trem-1 (triggering receptor expressed on myeloid cells 1) was upregulated in swine spleen cells in response to s. suis infection. the role of trem-1 signaling in enhancement of the proinflammatory response promoted us to examine its effect on the outcome of s. suis infection. in the present study, ...201526056380
rare events of intragenus and intraspecies horizontal transfer of the 16s rrna gene.horizontal gene transfer (hgt) of operational genes has been widely reported in prokaryotic organisms. however, informational genes such as those involved in transcription and translation processes are very difficult to be horizontally transferred, as described by woese's complexity hypothesis. here, we analyzed all of the completed prokaryotic genome sequences (2,143 genomes) in the ncbi (national center for biotechnology information) database, scanned for genomes with high intragenomic heterog ...201526220935
investigation of pathogenesis of h1n1 influenza virus and swine streptococcus suis serotype 2 co-infection in pigs by microarray analysis.swine influenza virus and streptococcus suis are two important contributors to the porcine respiratory disease complex, and both have significant economic impacts. clinically, influenza virus and streptococcus suis co-infections in pigs are very common, which often contribute to severe pneumonia and can increase the mortality. however, the co-infection pathogenesis in pigs is unclear. in the present study, co-infection experiments were performed using swine h1n1 influenza virus and streptococcus ...201525906258
functional and structural characterization of the antiphagocytic properties of a novel transglutaminase from streptococcus suis.streptococcus suis serotype 2 (ss2) is an important swine and human zoonotic pathogen. in the present study, we identified a novel secreted immunogenic protein, sstgase, containing a highly conserved eukaryotic-like transglutaminase (tgase) domain at the n terminus. we found that inactivation of sstgase significantly reduced the virulence of ss2 in a pig infection model and impaired its antiphagocytosis in human blood. we further solved the crystal structure of the n-terminal portion of the prot ...201526085092
isolation and characterization of a native avirulent strain of streptococcus suis serotype 2: a perspective for vaccine development.streptococcus suis, an emerging infectious pathogen, is the cause of two large-scale outbreaks of human streptococcal toxic shock syndrome in china, and has attracted much attention from the scientific community. the genetic basis of its pathogenesis remains enigmatic, and no effective prevention measures have been established. to better understand the virulence differentiation of s. suis and develop a promising vaccine, we isolated and sequenced a native avirulent s. suis strain (05has68). anim ...201525891917
streptococcus suis meningitis: a systematic review and meta-analysis.streptococcus suis is the most common cause of meningitis in pork consuming and pig rearing countries in south-east asia. we performed a systematic review of studies on s. suis meningitis to define the clinical characteristics, predisposing factors and outcome.201526505485
interactions of streptococcus suis serotype 2 with human meningeal cells and astrocytes.streptococcus suis serotype 2 is an important porcine pathogen and emerging zoonotic agent responsible for meningitis, of which different sequence types predominate worldwide. though bacterial meningitis is defined as an exacerbated inflammation of the meninges, the underlying astrocytes of the glia limitans superficialis may also be implicated. however, the interactions between this pathogen and human meningeal cells or astrocytes remain unknown. furthermore, the roles of well-described virulen ...201526502903
isolation, characterization and biological properties of membrane vesicles produced by the swine pathogen streptococcus suis.streptococcus suis, more particularly serotype 2, is a major swine pathogen and an emerging zoonotic agent worldwide that mainly causes meningitis, septicemia, endocarditis, and pneumonia. although several potential virulence factors produced by s. suis have been identified in the last decade, the pathogenesis of s. suis infections is still not fully understood. in the present study, we showed that s. suis produces membrane vesicles (mvs) that range in diameter from 13 to 130 nm and that appear ...201526110524
development and application of loop-mediated isothermal amplification assays based on its-1 for rapid detection of toxoplasma gondii in pork.the loop-mediated isothermal amplification (lamp) assay is a novel method that rapidly amplifies dna with high specificity and sensitivity under isothermal conditions. in this study, we established a lamp assay with six primers targeting a highly conserved region of toxoplasma gondii its-1 sequence. the amplification protocol completes within 30 min under isothermal condition in a 65°c water bath while specificity tests confirmed no cross-reactivity with dna templates of neospora caninum, eimeri ...201525624074
potential probiotic attributes of a new strain of bacillus coagulans cgmcc 9951 isolated from healthy piglet feces.a new strain of bacillus coagulans cgmcc 9551, which has a broad range of antibacterial activities against six main pathogenic bacteria including escherichia coli o8, staphylococcus aureus, salmonella enterica subsp. enterica serovar enteritidis, streptococcus suis, listeria monocytogenes and pasteurella multocida, was isolated from healthy piglet feces. in adhesion assay, the isolate exhibited a stronger adhesion to pig intestinal mucus than that of b. subtilis jt143 and l. acidophilus ly24 res ...201525752235
bacterial cell surface properties: role of loosely bound extracellular polymeric substances (lb-eps).this study investigated the effect of loosely bound extracellular polymeric substances (lb-eps) on the comprehensive surface properties of four bacteria (bacillus subtilis, streptococcus suis, escherichia coli and pseudomonas putida). the removal of lb-eps from bacterial surfaces by high-speed centrifugation (12,000×g) was confirmed by sem images. viability tests showed that the percentages of viable cells ranged from 95.9% to 98.0%, and no significant difference was found after treatment (p>0.0 ...201525805151
canada: distribution of streptococcus suis (from 2012 to 2014) and actinobacillus pleuropneumoniae (from 2011 to 2014) serotypes isolated from diseased pigs. 201526483588
erythema multiforme associated with respiratory disease in a commercial breeding pig herd.this study describes an erythema multiforme (em) in breeding sows, after their mixing in the group housing system. sows at 30-35 days of gestation showed red and raised skin areas, depression, anorexia, fever, respiratory problems, and increased return to estrus. blood and nasal samples from diseased sows were examined by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay for respiratory pathogens. hematological and biochemical analyses were performed on the blood sampl ...201526266696
investigations of selected pathogens among village pigs in central papua, indonesia.village pig husbandry is an important part of livestock production in papua province, eastern indonesia. however, high level of disease and mortality constrains production. the aim of this study was to investigate the prevalence of the selected pathogens in village pigs in the jayawijaya region of papua province, indonesia. two studies were conducted: study 1 determined the prevalence of selected pathogens in dead or moribund pigs sent to the main local market for sale. study 2 recorded the prev ...201626381546
acute meningitis of piglets and mice caused by co-infected with streptococcus suis and aerococcus viridans.the two opportunistic pathogens, streptococcus suis (s. suis) and aerococcus. viridans (a. viridans) were isolated from the brains of piglets suffered bacterial meningitis in a farm of china. the murine model has been established to evaluate the pathogenicity and symbiotic relationship of s. suis and a. viridans simultaneously infection. our results demonstrated the ability of new serotype s. suis to cause the classical bacterial meningitis and death were greatly enhanced during co-infection wit ...201627816682
chemical constituents from campylotropis hirtella.a phytochemical investigation on the roots of campylotropis hirtella afforded nine new isoflavones (3-9, 12, 15), two new isoflavans (10 and 11), one new coumestan (1), and three new prenylated benzoic acid derivatives (2, 13, 14), together with twenty-four known compounds. their structures were established by spectroscopic analysis and circular dichroism data. the isolated compounds were also evaluated for their antibacterial activities against enterococcus faecalis, salmonella gallinarum, stre ...201627220079
a novel inhibition elisa for the detection and monitoring of penicillium marneffei antigen in human serum.the thermally dimorphic fungus penicillium marneffei is a causative agent of penicilliosis marneffei, a disease considered to be an acquired immune deficiency syndrome (aids)-defining illness in southeast asia and southern china. we have developed an inhibition enzyme-linked immunosorbent assay (inh-elisa) incorporating the yeast phase specific mannoprotein-binding monoclonal antibody 4d1 for the detection of p. marneffei infection. in our sample set, the test detected antigenemia in all 45 (100 ...201626838686
genomic and proteomic characterization of se-i, a temperate bacteriophage infecting erysipelothrix rhusiopathiae.a bacteriophage infecting pathogenic erysipelothrix rhusiopathiae was isolated from a swine farm experiencing an outbreak of acute swine erysipelas; we designated this phage se-i. se-i has an icosahedral head, a long tail and a double-stranded dna genome. the 34,997-bp genome has a gc content of 34 % and contains 43 open reading frames (orfs) encoding packaging, structural, lysin-holin, and hypothetical proteins. components of purified se-i were separated using sds-page and analyzed using liquid ...201627541818
roles of the putative type iv-like secretion system key component vird4 and prsa in pathogenesis of streptococcus suis type 2.streptococcus suis type 2 (ss2) is a zoonotic pathogen causing septic infection, meningitis and pneumonia in pigs and humans. ss2 may cause streptococcal toxic shock syndrome (stss) probably due to excessive release of inflammatory cytokines. a previous study indicated that the vird4 gene in the putative type iv-like secretion system (t4ss) within the 89k pathogenicity island specific for recent epidemic strains contributed to the development of stss. however, the functional basis of vird4 in st ...201627995095
development of a sandwich elisa for ehec o157:h7 intimin γ1.enterohemorrhagic escherichia coli (ehec) o157:h7 is a zoonotic pathogen of worldwide importance that causes foodborne infections in humans. intimin gamma 1 (intimin γ1) is one of the most important outer membrane proteins required for ehec's intimate adhesion to epithelial cells. here, we generated a polyclonal antibody (pab) and a monoclonal antibody (mab) against intimin γ1 to develop a double antibody sandwich elisa (das-elisa) with increased sensitivity and specificity for measuring ehec o1 ...201627603508
immune-responsiveness of cd4(+) t cells during streptococcus suis serotype 2 infection.the pathogenesis of streptococcus suis infection, a major swine and human pathogen, is only partially understood and knowledge on the host adaptive immune response is critically scarce. yet, s. suis virulence factors, particularly its capsular polysaccharide (cps), enable this bacterium to modulate dendritic cell (dc) functions and potentially impair the immune response. this study aimed to evaluate modulation of t cell activation during s. suis infection and the role of dcs in this response. s. ...201627905502
identification of streptococcus suis meningitis through population-based surveillance, togo, 2010-2014.during 2010-2014, we enrolled 511 patients with suspected bacterial meningitis into surveillance in 2 districts of northern togo. we identified 15 persons with streptococcus suis infection; 10 had occupational contact with pigs, and 12 suffered neurologic sequelae. s. suis testing should be considered in rural areas of the african meningitis belt.201627314251
protection against streptococcus suis serotype 2 infection using a capsular polysaccharide glycoconjugate vaccine.streptococcus suis serotype 2 is an encapsulated bacterium and one of the most important bacterial pathogens in the porcine industry. despite decades of research for an efficient vaccine, none is currently available. based on the success achieved with other encapsulated pathogens, a glycoconjugate vaccine strategy was selected to elicit opsonizing anti-capsular polysaccharide (anti-cps) igg antibodies. in this work, glycoconjugate prototypes were prepared by coupling s. suis type 2 cps to tetanu ...201627113360
binding of human fibrinogen to mrp enhances streptococcus suis survival in host blood in a αxβ2 integrin-dependent manner.the gram-positive bacterium streptococcus suis serotype 2 (s. suis 2), an important zoonotic pathogen, induces strong systemic infections in humans; sepsis and meningitis are the most common clinical manifestations and are often accompanied by bacteremia. however, the mechanisms of s. suis 2 survival in human blood are not well understood. in our previous study, we identified muramidase-released protein (mrp), a novel human fibrinogen (hfg)-binding protein (fbp) in s. suis 2 that is an important ...201627231021
host-pathogen interactions in bacterial meningitis.bacterial meningitis is a devastating disease occurring worldwide with up to half of the survivors left with permanent neurological sequelae. due to intrinsic properties of the meningeal pathogens and the host responses they induce, infection can cause relatively specific lesions and clinical syndromes that result from interference with the function of the affected nervous system tissue. pathogenesis is based on complex host-pathogen interactions, some of which are specific for certain bacteria, ...201626744349
egfr transactivation contributes to neuroinflammation in streptococcus suis meningitis.streptococcus suis serotype 2 (ss2) is an important zoonotic bacterial pathogen in both humans and animals, which can cause high morbidity and mortality. meningitis is one of the major clinical manifestations of ss2 infection. however, the specific process of ss2 meningitis and its molecular mechanisms remain unclear. epidermal growth factor receptor (egfr) has been reported to initiate transduction of intracellular signals and regulate host inflammatory responses. whether and how egfr contribut ...201627756321
recruitment of factor h to the streptococcus suis cell surface is multifactorial.streptococcus suis is an important bacterial swine pathogen and a zoonotic agent. recently, two surface proteins of s. suis, fhb and fhbp, have been described for their capacity to bind factor h-a soluble complement regulatory protein that protects host cells from complement-mediated damages. results obtained in this study showed an important role of host factor h in the adhesion of s. suis to epithelial and endothelial cells. both fhb and fhbp play, to a certain extent, a role in such increased ...201627399785
simultaneous quantification and differentiation of streptococcus suis serotypes 2 and 9 by quantitative real-time pcr, evaluated in tonsillar and nasal samples of pigs.invasive streptococcus suis (s. suis) infections in pigs are often associated with serotypes 2 and 9. mucosal sites of healthy pigs can be colonized with these serotypes, often multiple serotypes per pig. to unravel the contribution of these serotypes in pathogenesis and epidemiology, simultaneous quantification of serotypes is needed. a quantitative real-time pcr (qpcr) targeting cps2j (serotypes 2 and 1/2) and cps9h (serotype 9) was evaluated with nasal and tonsillar samples from s. suis expos ...201627376336
evaluation of galleria mellonella larvae for studying the virulence of streptococcus suis.streptococcus suis is an encapsulated gram-positive bacterium and the leading cause of sepsis and meningitis in young pigs, resulting in considerable economic losses in the porcine industry. s. suis is considered an emerging zoonotic agent with increasing numbers of human cases over the last years. in the environment, both avirulent and virulent strains occur in pigs, with no evidence for consistent adapatation of virulent strains to the human host. currently, there is an urgent need for a conve ...201627978817
serological patterns of actinobacillus pleuropneumoniae, mycoplasma hyopneumoniae, pasteurella multocida and streptococcus suis in pig herds affected by pleuritis.respiratory illness is traditionally regarded as the disease of the growing pig, and has historically mainly been associated to bacterial infections with focus on mycoplasma hyopneumoniae and actinobacillus pleuropneumoniae. these bacteria still are of great importance, but continuously increasing herd sizes have complicated the scenario and the influence of secondary invaders may have been increased. the aim of this study was to evaluate the presence of a. pleuropneumoniae and m. hyopneumoniae, ...201627716292
a survey of porcine respiratory disease complex (prdc) associated pathogens among commercial pig farms of korea via oral fluid method.oral fluid analysis for monitoring herd is an interest in commercial pig farms in korea. the aim of this study was to investigate the positive rates and correlation of eight pathogens associated with porcine respiratory disease complex (prdc) by analyzing oral fluid samples from 214 pig groups from 56 commercial farms. the samples collected by rope-chewing method were analyzed with reverse-transcription polymerase chain reaction (rt-pcr) or standard pcr depending on microorganisms. the pathogens ...201627586468
monitoring of antimicrobial susceptibility of respiratory tract pathogens isolated from diseased cattle and pigs across europe, 2009-2012: vetpath results.vetpath is an ongoing pan-european antibiotic susceptibility monitoring programme that collects pathogens from diseased cattle, pigs and poultry. in the current study, 996 isolates from cattle and pig respiratory tract infections were tested for their antimicrobial susceptibilities. non-replicate lung samples or nasopharyngeal/nasal swabs were collected from animals with acute clinical signs in 10 countries during 2009-2012. pasteurella multocida, mannheimia haemolytica and histophilus somni fro ...201627102206
preparation, characterization and pharmacokinetics of doxycycline hydrochloride and florfenicol polyvinylpyrroliddone microparticle entrapped with hydroxypropyl-β-cyclodextrin inclusion complexes suspension.in order to effectively control the bacterial pneumonia in pigs, doxycycline hydrochloride (doxhcl) and florfenicol (ff) microparticle suspension together with inclusion complexes was prepared by using hydroxypropyl-β-cyclodextrin (hp-β-cd) as host molecules, polyvinylpyrroliddone (pvp) as polymer carriers and hydroxypropyl methyl cellulose (hpmc) as suspending agents. in vitro antibacterial activity, properties, stability and pharmacokinetics of the suspension were studied. the results demonstr ...201626918512
auxotrophic actinobacillus pleurpneumoniae grows in multispecies biofilms without the need for nicotinamide-adenine dinucleotide (nad) supplementation.actinobacillus pleuropneumoniae is the etiologic agent of porcine contagious pleuropneumonia, which causes important worldwide economic losses in the swine industry. several respiratory tract infections are associated with biofilm formation, and a. pleuropneumoniae has the ability to form biofilms in vitro. biofilms are structured communities of bacterial cells enclosed in a self-produced polymer matrix that are attached to an abiotic or biotic surface. virtually all bacteria can grow as a biofi ...201627349384
gida, a trna modification enzyme, contributes to the growth, and virulence of streptococcus suis serotype 2.glucose-inhibited division protein (gida), is a trna modification enzyme functioning together with mnme in the addition of a carboxymethylaminomethyl group to position 5 of the anticodon wobble uridine of trna. here, we report a gida homolog from a chinese isolate sc-19 of the zoonotic streptococcus suis serotype 2 (ss2). gida disruption led to a defective growth, increased capsule thickness, and reduced hemolytic activity. moreover, the gida deletion mutant (δgida) displayed reduced mortality a ...201627148493
functional definition of bira suggests a biotin utilization pathway in the zoonotic pathogen streptococcus suis.biotin protein ligase is universal in three domains of life. the paradigm version of bpl is the escherichia coli bira that is also a repressor for the biotin biosynthesis pathway. streptococcus suis, a leading bacterial agent for swine diseases, seems to be an increasingly-important opportunistic human pathogen. unlike the scenario in e. coli, s. suis lacks the de novo biotin biosynthesis pathway. in contrast, it retains a bioy, a biotin transporter-encoding gene, indicating an alternative survi ...201627217336
sub-mics of azithromycin decrease biofilm formation of streptococcus suis and increase capsular polysaccharide content of s. suis.streptococcus suis (s. suis) caused serious disease symptoms in humans and pigs. s. suis is able to form thick biofilms and this increases the difficulty of treatment. after growth with 1/2 minimal inhibitory concentration (mic) of azithromycin, 1/4 mic of azithromycin, or 1/8 mic of azithromycin, biofilm formation of s. suis dose-dependently decreased in the present study. furthermore, scanning electron microscopy analysis revealed the obvious effect of azithromycin against biofilm formation of ...201627812354
clearance of streptococcus suis in stomach contents of differently fed growing pigs.streptococcus (s.) suis translocates across the intestinal barrier of piglets after intraintestinal application. based on these findings, an oro-gastrointestinal infection route has been proposed. thus, the objective of this study was to investigate the survival of s. suis in the porcine stomach. whereas surviving bacteria of s. suis serotypes 2 and 9 were not detectable after 60 min of incubation in stomach contents with a comparatively high gastric ph of 5 due to feeding of fine pellets, the n ...201627509526
a cluster of streptococcus suis meningitis in a family who traveled to taiwan from southern vietnam. 201625081989
in vivo pharmacodynamics of cefquinome in a neutropenic mouse thigh model of streptococcus suis serotype 2 at varied initial inoculum sizes.streptococcus suis serotype 2 is an emerging zoonotic pathogen and causes severe disease in both pigs and human beings. cefquinome (ceq), a fourth-generation cephalosporin, exhibits broad-spectrum activity against gram-positive bacteria such as s. suis. this study evaluated the in vitro and in vivo antimicrobial activities of ceq against four strains of s. suis serotype 2 in a murine neutropenic thigh infection model. we investigated the effect of varied inoculum sizes (10(6) to 10(8) cfu/thigh) ...201626666923
[case report; a case of streptococcus suis meningitis which caused bilateral sensorineural hearing loss was improved due to the cochlear implantation]. 201627491267
temporal and spatial association of streptococcus suis infection in humans and porcine reproductive and respiratory syndrome outbreaks in pigs in northern vietnam.porcine reproductive and respiratory syndrome (prrs) outbreaks in pigs are associated with increased susceptibility of pigs to secondary bacterial infections, including streptococcus suis - an important zoonotic pathogen causing bacterial meningitis in humans. this case-control study examined the association between human s. suis infection and prrs outbreaks in pigs in northern vietnam. we included 90 s. suis case-patients and 183 non-s. suis sepsis controls from a referral hospital in hanoi in ...201625997360
characterisation of a novel integrative and conjugative element icessd9 carrying erm(b) and tet(o) resistance determinants in streptococcus suis, and the distribution of icessd9-like elements in clinical isolates.this study identified a novel integrative and conjugative element (icessd9) carrying erm(b) and tet(o) resistance determinants in streptococcus suis d9 and determined its prevalence in clinical isolates. comparative genome analysis was performed using mauve and artemis comparison tool visualisation programs. inverse pcr was utilised to detect its circular intermediate. the transfer capacity of icessd9 was evaluated by mating assays using s. suis a7 and enterococcus faecalis jh2-2 as recipients. ...201627531000
transcriptional analysis of prrsv-infected porcine dendritic cell response to streptococcus suis infection reveals up-regulation of inflammatory-related genes expression.the porcine reproductive and respiratory syndrome virus (prrsv) is one of the most important swine pathogens and often serves as an entry door for other viral or bacterial pathogens, of which streptococcus suis is one of the most common. pre-infection with prrsv leads to exacerbated disease caused by s. suis infection. very few studies have assessed the immunological mechanisms underlying this higher susceptibility. since antigen presenting cells play a major role in the initiation of the immune ...201627213692
effects of dietary fibre source on microbiota composition in the large intestine of suckling piglets.this study aimed to investigate the effects of dietary fibre sources on the gut microbiota in suckling piglets, and to test the hypothesis that a moderate increase of dietary fibre may affect the gut microbiota during the suckling period. suckling piglets were fed different fibre-containing diets or a control diet from postnatal day 7 to 22. digesta samples from cecum, proximal colon and distal colon were used for pig intestinal tract chip analysis. the data showed that the effects of fibre-cont ...201627231242
expression of a tandemly arrayed plectasin gene from pseudoplectania nigrella in pichia pastoris and its antimicrobial activity.in recent years, various naturally occurring defence peptides such as plectasin have attracted considerable research interest because they could serve as alternatives to antibiotics. however, the production of plectasin from natural microorganisms is still not commercially feasible because of its low expression levels and weak stability. a tandemly arrayed plectasin gene (1,002 bp) from pseudoplectania nigrella was generated using the isoschizomer construction method, and was inserted into the p ...201626643963
evolution and diversity of the antimicrobial resistance associated mobilome in streptococcus suis: a probable mobile genetic elements reservoir for other streptococci.streptococcus suis is a previously neglected, newly emerging multidrug-resistant zoonotic pathogen. mobile genetic elements (mges) play a key role in intra- and interspecies horizontal transfer of antimicrobial resistance (amr) determinants. although, previous studies showed the presence of several mges, a comprehensive analysis of amr-associated mobilome as well as their interaction and evolution has not been performed. in this study, we presented the amr-associated mobilome and their insertion ...201627774436
comparative genomic analysis of the icesa2603 family ices and spread of erm(b)- and tet(o)-carrying transferable 89k-subtype ices in swine and bovine isolates in china.integrative and conjugative elements (ices) of the icesa2603 family have been isolated from several species of streptococcus spp.; however, the comparative genomic and evolutionary analyses of these particular ices are currently only at their initial stages. by investigating 13 ices of the icesa2603 family and two icesa2603 family-like ices derived from diverse hosts and locations, we have determined that ices comprised a backbone of 30 identical syntenic core genes and accessory genes that were ...201626870017
screening for antibacterial and antioxidant activities and phytochemical analysis of oroxylum indicum fruit extracts.oroxylum indicum, which is called pheka in thai, is a traditional thai plant in the bignoniaceae family with various ethnomedical uses such as as an astringent, an anti-inflammatory agent, an anti-bronchitic agent, an anti-helminthic agent and an anti-microbial agent. the young fruits of this plant have also been consumed as vegetables. however, there has been no report concerning its antibacterial activities, especially activities related to clinically isolated pathogenic bacteria and the in vi ...201627070560
a novel suicide shuttle plasmid for streptococcus suis serotype 2 and streptococcus equi ssp. zooepidemicus gene mutation.the mariner-based himar1 system has been utilized for creating mutant libraries of many gram-positive bacteria. streptococcus suis serotype 2 (ss2) and streptococcus equi ssp. zooepidemicus (sez) are primary pathogens of swine that threaten the swine industry in china. to provide a forward-genetics technology for finding virulent phenotype-related genes in these two pathogens, we constructed a novel temperature-sensitive suicide shuttle plasmid, pmar4s, which contains the himar1 system transposo ...201627256117
molecular and antimicrobial susceptibility profiling of atypical streptococcus species from porcine clinical specimens.the streptococcus species present broad phenotypic variation, making identification difficult using only traditional microbiological methods. even though streptococcus suis is the most important species for the worldwide swine industry, other streptococcus species appear to be able to cause disease in swine and could represent a higher underestimated risk for porcine health. the aim of this study was to identify streptococcus-like isolates by maldi-tof ms and 16s rrna sequencing and further mole ...201627491454
streptococcus suis serotype 2 strains isolated in argentina (south america) are different from those recovered in north america and present a higher risk for humans.streptococcus suis serotype 2 is an important swine pathogen and emerging zoonotic agent causing meningitis and septicemia/septic shock. strains are usually virulent (eurasia) or of intermediate/low virulence (north america). very few data regarding human and swine isolates from south america are available.201628348788
a novel virulence-associated protein, vape, in streptococcus suis serotype 2.streptococcus suis serotype 2 (ss2) is an important pathogen that affects pigs. however, neither its virulence nor its pathogenesis of infection has yet to be fully elucidated. the present study identifies a novel virulence‑associated protein e gene (vape) of ss2. to investigate the importance of vape in ss2 infection, a vape knock‑out mutant based on ss2 wild‑type strain zy458 was designated 458δvape. 458δvape was generated through homologous recombination, using a combined plasmid with a vape ...201626821177
characterization of iga1 protease as a surface protective antigen of streptococcus suis serotype 2.iga1 protease of streptococcus suis serotype 2 (ss2) has been proven to be relative with virulence and immunogenicity, however, its protective efficacy remained to be evaluated. the present study found evidence that immunization with purified recombinant iga1 protease (600-1926aa) could induce high igg antibody titers and could confer complete protection against a challenge with a lethal dose of ss2 in a mouse model. in addition, our findings confirmed that the iga1 protease distributes on the s ...201626774332
enolase of streptococcus suis serotype 2 enhances blood-brain barrier permeability by inducing il-8 release.streptococcus suis serotype 2 (ss2) is an emerging zoonosis, and meningitis is the most frequent clinical manifestation, but mechanism of its virulent factor, enolase (eno), is unknown in meningitis. in this study, eno was inducibly expressed and added to an in vitro transwell co-culture model of the blood-brain barrier (bbb) consisted of porcine brain microvascular endothelial cells (pbmecs) and astrocytes (acs), the results showed that eno induces a significant increase in bbb permeability and ...201626732390
a novel prophage lysin ply5218 with extended lytic activity and stability against streptococcus suis infection.streptococcus suis (s. suis) is an emerging zoonotic agent that exhibits high level resistance to classic antibiotics and a heavy burden in the swine industry. therefore alternative antibacterial agents need to be developed. a novel endolysin derived from the s. suis temperate phage phi5218, termed ply5218, was identified. the minimum inhibitory concentration (mic) of ply5218 was 2.5 μg ml(-1) against s. suis strain ha9801, an activity many times greater than the lysins reported previously (mic ...201627481700
characterization of the immune response and evaluation of the protective capacity of rssna against streptococcus suis infection in pigs.the efforts made to develop vaccines against streptococcus suis have failed because of lack of common antigens cross-reactive against different serotypes of this species. the cell wall-anchored proteins can be good vaccine candidates due to their high expression and accessibility to antibodies, among these, a cell-wall protein, dna-nuclease (ssna), present in most of the s. suis serotypes and clinical isolates collected from infected pigs, was selected. an experimental challenge against s. suis ...201627477507
characterization of spectinomycin resistance in streptococcus suis leads to two novel insights into drug resistance formation and dissemination mechanism.spectinomycin is an aminocyclitol antibiotic used clinically to treat a variety of infections in animals. here, we characterized drug resistance prevalence in clinical streptococcus suis isolates and discovered a novel resistance mechanism in which the s5 mutation (gly26asp) results in high spectinomycin resistance. additionally, a novel integrative and conjugative element encompassing a multidrug resistance spw_like-aade-lnu(b)-lsa(e) cluster and a cadmium resistance operon were identified, sug ...201627458226
flps, the fnr-like protein of streptococcus suis is an essential, oxygen-sensing activator of the arginine deiminase system.streptococcus (s.) suis is a zoonotic pathogen causing septicemia and meningitis in pigs and humans. during infection s. suis must metabolically adapt to extremely diverse environments of the host. ccpa and the fnr family of bacterial transcriptional regulators are important for metabolic gene regulation in various bacteria. the role of ccpa in s. suis is well defined, but the function of the fnr-like protein of s. suis, flps, is yet unknown. transcriptome analyses of wild-type s. suis and a flp ...201627455333
determining streptococcus suis serotype from short-read whole-genome sequencing data.streptococcus suis is divided into 29 serotypes based on a serological reaction against the capsular polysaccharide (cps). multiplex pcr tests targeting the cps locus are also used to determine s. suis serotypes, but they cannot differentiate between serotypes 1 and 14, and between serotypes 2 and 1/2. here, we developed a pipeline permitting in silico serotype determination from whole-genome sequencing (wgs) short-read data that can readily identify all 29 s. suis serotypes.201627449127
fatal septic meningitis in child caused by streptococcus suis serotype 24. 201627439179
comparative genome analyses of streptococcus suis isolates from endocarditis demonstrate persistence of dual phenotypic clones.many bacterial species coexist in the same niche as heterogeneous clones with different phenotypes; however, understanding of infectious diseases by polyphenotypic bacteria is still limited. in the present study, encapsulation in isolates of the porcine pathogen streptococcus suis from persistent endocarditis lesions was examined. coexistence of both encapsulated and unencapsulated s. suis isolates was found in 26 out of 59 endocarditis samples. the isolates were serotype 2, and belonged to two ...201627433935
formate-tetrahydrofolate ligase is involved in the virulence of streptococcus suis serotype 2.streptococcus suis is an emerging zoonotic pathogen that causes severe infections in pigs and humans. however, the pathogenesis of s. suis remains unclear. the present study targeted a putative virulence-associated factor (fhs, encoding the formate-tetrahydrofolate ligase) of s. suis. to investigate the role of fhs in the virulence potential of s. suis serotype 2, an fhs deletion mutant (δfhs) and the corresponding complementation strain (cδfhs) were generated. the δfhs mutant displayed similar ...201627427088
structure determination of streptococcus suis serotype 9 capsular polysaccharide and assignment of functions of the cps locus genes involved in its biosynthesis.streptococcus suis serotype 9 is the most prevalent s. suis serotype in several european countries. in spite of its pathogenicity for pigs and increasing zoonotic potential, limited information is available on this serotype. here we determined for the first time the chemical composition and structure of serotype 9 capsular polysaccharide (cps), a major bacterial virulence factor and the antigen at the origin of s. suis classification into serotypes. chemical and spectroscopic data gave the repea ...201627423880
virulence studies of different sequence types and geographical origins of streptococcus suis serotype 2 in a mouse model of infection.multilocus sequence typing previously identified three predominant sequence types (sts) of streptococcus suis serotype 2: st1 strains predominate in eurasia while north american (na) strains are generally st25 and st28. however, st25/st28 and st1 strains have also been isolated in asia and na, respectively. using a well-standardized mouse model of infection, the virulence of strains belonging to different sts and different geographical origins was evaluated. results demonstrated that although a ...201627409640
an emerging zoonotic clone in the netherlands provides clues to virulence and zoonotic potential of streptococcus suis.streptococcus suis is a zoonotic swine pathogen and a major public health concern in asia, where it emerged as an important cause of bacterial meningitis in adults. while associated with food-borne transmission in asia, zoonotic s. suis infections are mainly occupational hazards elsewhere. to identify genomic differences that can explain zoonotic potential, we compared whole genomes of 98 s. suis isolates from human patients and pigs with invasive disease in the netherlands, and validated our ob ...201627381348
increase of β2-integrin on adhesion of thp-1 cells to collagen vitrigel membrane.when human monocyte-derived leukemia (thp-1) cells, which are floating cells, are stimulated with lipid peroxides, or streptococcus suis, these cells adhere to a plastic plate or endothelial cells. however, it is unclear whether or not non-stimulated thp-1 cells adhere to collagen vitrigel membrane (cvm). in this study, firstly, we investigated the rate of adhesion of thp-1 cells to cvm. when thp-1 cells were not stimulated, the rate of adhesion to cvm was high. then, to identify adhesion molecu ...201627379801
[isolation and characterization of a streptococcus suis serotype 9 from a wild cat].streptococcus suis (s. suis) is an emerging zoonotic pathogenic bacterium capable of infecting piglets and human and with sporadic infections in a variety of mammalian species. the aim of this study is to investigate the prevalence of s. suis in wild cats.201627373075
biological activities of suilysin: role in streptococcus suis pathogenesis.streptococcus suis is an important swine and zoonotic pathogen equipped with several virulence factors. the pore-forming toxins are the most abundant bacterial toxins and classified as critical virulence (associated) factors of several pathogens. the role of suilysin (sly), a pore-forming cholesterol-dependent cytolysin of s. suis, as a true virulence factor is under debate. most of the bacterial toxins have been reported to modulate the host immune system to facilitate invasion and subsequent r ...201627357518
live streptococcus suis type 5 strain xs045 provides cross-protection against infection by strains of types 2 and 9.streptococcus suis is one of the common pathogens causing diseases in pigs and covers 35 serotypes with the type 2 strains being more pathogenic and zoonotic. existing inactivated or subunit vaccines, in clinical use or under trial, could not provide cross protection against other serotypes. we identified a natural low-virulence s. suis type 5 strain xs045 as a live vaccine candidate because it is highly adhesive to the cultured hep-2 cells, but with no apparent pathogenicity in mice and piglets ...201627349838
current taxonomical situation of streptococcus suis.streptococcus suis, a major porcine pathogen and an important zoonotic agent, is considered to be composed of phenotypically and genetically diverse strains. however, recent studies reported several "s. suis-like strains" that were identified as s. suis by commonly used methods for the identification of this bacterium, but were regarded as distinct species from s. suis according to the standards of several taxonomic analyses. furthermore, it has been suggested that some s. suis-like strains can ...201627348006
mechanisms of host-pathogen protein complex formation and bacterial immune evasion of streptococcus suis protein fhb.streptococcus suis serotype 2 (s. suis 2)-induced sepsis and meningitis are often accompanied by bacteremia. the evasion of polymorphonuclear leukocyte-mediated phagocytic clearance is central to the establishment of bacteremia caused by s. suis 2 and is facilitated by the ability of factor h (fh)-binding protein (fhb) to bind fh on the bacterial surface, thereby impeding alternative pathway complement activation and phagocytic clearance. here, c3b/c3d was found to bind to fhb, along with fh, fo ...201627342778
astrocytes enhance streptococcus suis-glial cell interaction in primary astrocyte-microglial cell co-cultures.streptococcus (s.) suis infections are the most common cause of meningitis in pigs. moreover, s. suis is a zoonotic pathogen, which can lead to meningitis in humans, mainly in adults. we assume that glial cells may play a crucial role in host-pathogen interactions during s. suis infection of the central nervous system. glial cells are considered to possess important functions during inflammation and injury of the brain in bacterial meningitis. in the present study, we established primary astrocy ...201627304968
antimicrobial activity of penicillin g and n-acetylcystein on planktonic and sessile cells of streptococcus suis.the aim of this study was to investigate the capacity of streptococcus suis strains to form biofilms and to evaluate the antimicrobial activity of penicillin g and n-acetylcystein (nac) on both s. suis sessile and planktonic forms. only non-typeable isolates of s. suis were correlated with a greater biofilm formation capacity. the mci of penicillin g and nac required for inhibiting biofilm growth were higher than the required concentration for inhibiting planktonic growth. the combinations of na ...201627282001
subtilisin-like protease-1 secreted through type iv secretion system contributes to high virulence of streptococcus suis 2.streptococcus suis serotype 2 is an emerging zoonotic pathogen that triggered two outbreaks of streptococcal toxic shock syndrome (stss) in china. our previous research demonstrated that a type iv secretion system (t4ss) harbored in the 89k pathogenicity island contributes to the pathogenicity of s. suis 2. in the present study, a shotgun proteomics approach was employed to identify the effectors secreted by t4ss in s. suis 2, and surface-associated subtilisin-like protease-1 (sspa-1) was identi ...201627270879
the roles of rela/(p)ppgpp in glucose-starvation induced adaptive response in the zoonotic streptococcus suis.the (p)ppgpp signal molecules play a central role in the stringent response (sr) to adapt to nutrient starvation in bacteria, yet the carbohydrate starvation induced adaptive response and the roles of sr in this response is not well characterized, especially in gram-positives. here, two (p)ppgpp synthetases rela and relq are identified in streptococcus suis, an important emerging zoonotic gram-positive bacterium, while only rela is functional under glucose starvation. to characterize the roles o ...201627255540
efficient suilysin-mediated invasion and apoptosis in porcine respiratory epithelial cells after streptococcal infection under air-liquid interface conditions.streptococci may colonize the epithelium in the airways and other entry sites. while local infection often remains asymptomatic, severe or even fatal diseases occur when streptococci become invasive and spread to different sites in the infected host. we have established porcine respiratory air-liquid interface cultures (ali) from the porcine lung to analyze the interaction of streptococci with their primary target cells. as representative of the streptococcal family we chose streptococcus suis ( ...201627229328
loss of 89k pathogenicity island in epidemic streptococcus suis, china. 201627192444
impact of serotype and sequence type on the preferential aerosolization of streptococcus suis.streptococcus suis is a swine pathogen that causes pneumonia, septicemia and meningitis. it is also an important zoonotic agent responsible of several outbreaks in china. s. suis strains are classified into 35 serotypes based on the composition of their polysaccharide capsule. s. suis serotype 2 causes the majority of severe infections in pigs and in human, and can be further subdivided into sequence types (sts) based on multilocus sequence typing. the st1 is associated with highly virulent stra ...201627180230
metabolic context of the competence-induced checkpoint for cell replication in streptococcus suis.natural genetic transformation is a transient, rapidly progressing energy-consuming process characterized by expression of the transformasome and competence-associated regulatory genes. this transient state is tightly controlled to avoid potentially adverse effects of genetic recombination on genome integrity during cell division. we investigated the global response of streptococcus suis to exposure to the sigx competence-inducing peptide (xip), and thus to the activation of the competence machi ...201627149631
Refresh
firstprev
...1112131415
nextlast
Displaying items 1201 - 1300 of 1416