| phase i safety and immunogenicity study of a candidate meningococcal disease vaccine based on neisseria lactamica outer membrane vesicles. | natural immunity to meningococcal disease in young children is associated epidemiologically with carriage of commensal neisseria species, including neisseria lactamica. we have previously demonstrated that outer membrane vesicles (omvs) from n. lactamica provide protection against lethal challenge in a mouse model of meningococcal septicemia. we evaluated the safety and immunogenicity of an n. lactamica omv vaccine in a phase i placebo-controlled, double-blinded clinical trial. ninety-seven heal ... | 2009 | 19553555 |
| rapid real-time pcr assays for detection of klebsiella pneumoniae with the rmpa or maga genes associated with the hypermucoviscosity phenotype: screening of nonhuman primates. | the relationship of mucoviscosity-associated (maga) and/or regulator of mucoid phenotype (rmpa) genes to the klebsiella pneumoniae hypermucoviscosity (hmv) phenotype has been reported. we previously demonstrated that rmpa+ k. pneumoniae can cause serious disease in african green monkeys and isolated rmpa+ and maga+ hmv k. pneumoniae from other species of non-human primates. to rapidly screen african green monkeys/non-human primates for these infections, we developed three real-time pcr assays. t ... | 2009 | 19644019 |
| identifying currents in the gene pool for bacterial populations using an integrative approach. | the evolution of bacterial populations has recently become considerably better understood due to large-scale sequencing of population samples. it has become clear that dna sequences from a multitude of genes, as well as a broad sample coverage of a target population, are needed to obtain a relatively unbiased view of its genetic structure and the patterns of ancestry connected to the strains. however, the traditional statistical methods for evolutionary inference, such as phylogenetic analysis, ... | 2009 | 19662158 |
| 16th international pathogenic neisseria conference: recent progress towards effective meningococcal disease vaccines. | the report describes developments in meningococcal disease vaccines presented at the 16th international pathogenic neisseria conference, rotterdam, 7-12 september 2008. great progress has been made by the meningitis vaccine project to provide an affordable and effective serogroup a conjugate vaccine for use in the meningitis belt of sub-saharan africa. the vaccine has been shown to be safe and to produce excellent immune response in phase 2 clinical trials in india and africa in the target popul ... | 2009 | 19684470 |
| variation of the factor h-binding protein of neisseria meningitidis. | there is currently no comprehensive meningococcal vaccine, due to difficulties in immunizing against organisms expressing serogroup b capsules. to address this problem, subcapsular antigens, particularly the outer-membrane proteins (omps), are being investigated as candidate vaccine components. if immunogenic, however, such antigens are often antigenically variable, and knowledge of the extent and structuring of this diversity is an essential part of vaccine formulation. factor h-binding protein ... | 2009 | 19729409 |
| evaluation of a novel real-time pcr test based on the ssra gene for the identification of group b streptococci in vaginal swabs. | despite the implementation of prevention guidelines, early-onset group b streptococci (gbs) disease remains a cause of neonatal morbidity and mortality worldwide. strategies to identify women who are at risk of transmitting gbs to their infant and the administration of intrapartum antibiotics have greatly reduced the incidence of neonatal gbs disease. however, there is a requirement for a rapid diagnostic test for gbs that can be carried out in a labour ward setting especially for women whose gb ... | 2009 | 19732424 |
| immunoproteomic analysis of the development of natural immunity in subjects colonized by neisseria meningitidis reveals potential vaccine candidates. | the potential protective effect of existing vaccines against serogroup b meningococci, based on outer membrane proteins, is limited by strain restriction and apparent short duration of immune responses. in contrast, meningococcal colonization is known to stimulate the production of cross-protective antibodies as defined by the development of serum bactericidal activity (sba) against heterologous serogroup b strains. in the current study, a resource of human serum samples and meningococcal carria ... | 2009 | 19737898 |
| assessment of vaccine potential of the neisseria-specific protein nmb0938. | the availability of complete genome sequence of neisseria meningitidis serogroup b strain mc58 and reverse vaccinology has allowed the discovery of several novel antigens. here, we have explored the potential of n. meningitidis lipoprotein nmb0938 as a vaccine candidate, based on investigation of gene sequence conservation and the antibody response elicited after immunization in mice. this antigen was previously identified by a genome-based approach as an outer membrane lipoprotein unique to the ... | 2009 | 19751688 |
| biochemical and genomic analysis of the denitrification pathway within the genus neisseria. | since neisseria gonorrhoeae and neisseria meningitidis are obligate human pathogens, a comparison with commensal species of the same genus could reveal differences important in pathogenesis. the recent completion of commensal neisseria genome draft assemblies allowed us to perform a comparison of the genes involved in the catalysis, assembly and regulation of the denitrification pathway, which has been implicated in the virulence of several bacteria. all species contained a highly conserved nitr ... | 2009 | 19762442 |
| international external quality assurance for laboratory diagnosis of diphtheria. | the diphtheria surveillance network (dipnet) encompassing national diphtheria reference centers from 25 european countries is a dedicated surveillance network recognized by the european commission. a key dipnet objective is the quality assessment of microbiological procedures for diphtheria across the european union and beyond. a detailed questionnaire on the level of reference laboratory services and an external quality assessment (eqa) panel comprising six simulated throat specimens were sent ... | 2009 | 19828749 |
| regulatory role of the misr/s two-component system in hemoglobin utilization in neisseria meningitidis. | outer membrane iron receptors are some of the major surface entities that are critical for meningococcal pathogenesis. the gene encoding the meningococcal hemoglobin receptor, hmbr, is both independently transcribed and transcriptionally linked to the upstream gene hemo, which encodes a heme oxygenase. the misr/s two-component system was previously determined to regulate hmbr transcription, and its hemo and hmbr regulatory mechanisms were characterized further here. the expression of hemo and hm ... | 2010 | 20008531 |
| regulatory role of the misr/s two-component system in hemoglobin utilization in neisseria meningitidis. | outer membrane iron receptors are some of the major surface entities that are critical for meningococcal pathogenesis. the gene encoding the meningococcal hemoglobin receptor, hmbr, is both independently transcribed and transcriptionally linked to the upstream gene hemo, which encodes a heme oxygenase. the misr/s two-component system was previously determined to regulate hmbr transcription, and its hemo and hmbr regulatory mechanisms were characterized further here. the expression of hemo and hm ... | 2010 | 20008531 |
| frequency of factor h-binding protein modular groups and susceptibility to cross-reactive bactericidal activity in invasive meningococcal isolates. | meningococcal factor h-binding protein (fhbp) is a promising vaccine candidate that elicits serum bactericidal antibodies in humans. based on sequence variability of the entire protein, fhbp has been divided into three variant groups or two sub-families. we recently reported that the fhbp architecture was modular, consisting of five variable segments, each encoded by genes from one of two lineages. based on combinations of segments from different lineages, all 70 known fhbp sequence variants cou ... | 2010 | 20044056 |
| frequency of factor h-binding protein modular groups and susceptibility to cross-reactive bactericidal activity in invasive meningococcal isolates. | meningococcal factor h-binding protein (fhbp) is a promising vaccine candidate that elicits serum bactericidal antibodies in humans. based on sequence variability of the entire protein, fhbp has been divided into three variant groups or two sub-families. we recently reported that the fhbp architecture was modular, consisting of five variable segments, each encoded by genes from one of two lineages. based on combinations of segments from different lineages, all 70 known fhbp sequence variants cou ... | 2010 | 20044056 |
| review of meningococcal group b vaccines. | no broadly effective vaccines are available for prevention of group b meningococcal disease, which accounts for >50% of all cases. the group b capsule is an autoantigen and is not a suitable vaccine target. outer-membrane vesicle vaccines appear to be safe and effective, but serum bactericidal responses in infants are specific for a porin protein, pora, which is antigenically variable. to broaden protection, outer-membrane vesicle vaccines have been prepared from >1 strain, from mutants with >1 ... | 2010 | 20144017 |
| genomic content of neisseria species. | the physical properties of most bacterial genomes are largely unexplored. we have previously demonstrated that the strict human pathogen neisseria gonorrhoeae is polyploid, carrying an average of three chromosome copies per cell and only maintaining one pair of replication forks per chromosome (d. m. tobiason and h. s. seifert, plos biol. 4:1069-1078, 2006). we are following up this initial report to test several predictions of the polyploidy model of gonococcal chromosome organization. we demon ... | 2010 | 20172999 |
| filifactor alocis--involvement in periodontal biofilms. | bacteria in periodontal pockets develop complex sessile communities that attach to the tooth surface. these highly dynamic microfloral environments challenge both clinicians and researchers alike. the exploration of structural organisation and bacterial interactions within these biofilms is critically important for a thorough understanding of periodontal disease. in recent years, filifactor alocis, a fastidious, gram-positive, obligately anaerobic rod was repeatedly identified in periodontal les ... | 2010 | 20193074 |
| coevolution of dna uptake sequences and bacterial proteomes. | dramatic examples of repeated sequences occur in the genomes of some naturally competent bacteria, which contain hundreds or thousands of copies of short motifs called dna uptake signal sequences. here, we analyze the evolutionary interactions between coding-region uptake sequences and the proteomes of haemophilus influenzae, actinobacillus pleuropneumoniae, and neisseria meningitidis. in all three genomes, uptake sequence accumulation in coding sequences has approximately doubled the frequencie ... | 2009 | 20333176 |
| genetic, structural, and antigenic analyses of glycan diversity in the o-linked protein glycosylation systems of human neisseria species. | bacterial capsular polysaccharides and lipopolysaccharides are well-established ligands of innate and adaptive immune effectors and often exhibit structural and antigenic variability. although many surface-localized glycoproteins have been identified in bacterial pathogens and symbionts, it not clear if and how selection impacts associated glycoform structure. here, a systematic approach was devised to correlate gene repertoire with protein-associated glycoform structure in neisseria species imp ... | 2010 | 20363948 |
| conjugative plasmids of neisseria gonorrhoeae. | many clinical isolates of the human pathogen neisseria gonorrhoeae contain conjugative plasmids. the host range of these plasmids is limited to neisseria species, but presence of a tetracycline (tetm) determinant inserted in several of these plasmids is an important cause of the rapid spread of tetracycline resistance. previously plasmids with different backbones (dutch and american type backbones) and with and without different tetm determinants (dutch and american type tetm determinants) have ... | 2010 | 20376355 |
| neisseria lactamica arthritis and septicemia complicating myeloma. | | 2010 | 20410341 |
| innate immune function of the neisserial porins and the relationship to vaccine adjuvant activity. | neisseria meningitidis is a gram-negative pathogenic bacteria responsible for bacterial meningitis and septicemia. porins are the most represented outer membrane proteins in the pathogenic neisseria species, functioning as pores for the exchange of ions, and are characterized by a trimeric beta-barrel structure. neisserial porins have been shown to act as adjuvants in the immune response via activation of b cells and other antigen-presenting cells. their effect on the immune response is mediated ... | 2010 | 20441547 |
| evaluation of the analytical performance of the xpert mtb/rif assay. | we performed the first studies of analytic sensitivity, analytic specificity, and dynamic range for the new xpert mtb/rif assay, a nucleic acid amplification-based diagnostic system that detects mycobacterium tuberculosis and rifampin (rif) resistance in under 2 h. the sensitivity of the assay was tested with 79 phylogenetically and geographically diverse m. tuberculosis isolates, including 42 drug-susceptible isolates and 37 rif-resistant isolates containing 13 different rpob mutations or mutat ... | 2010 | 20504986 |
| candidate vaginal microbicides with activity against chlamydia trachomatis and neisseriagonorrhoeae. | vaginal microbicides with activity towards organisms that cause sexually transmitted infections have been proposed as a strategy to reduce transmission. small-molecule inhibitors of chlamydia trachomatis serovar d belonging to the class of salicylidene acylhydrazides (inps) have been shown to work through a mechanism that involves iron restriction. expanding on this work, ten inps were tested against a lymphogranuloma venereum strain of c. trachomatis (serovar l2), neisseria gonorrhoeae, and hyd ... | 2010 | 20605703 |
| distinct cell death programs in monocytes regulate innate responses following challenge with common causes of invasive bacterial disease. | peripheral blood monocytes represent the rapid response component of mononuclear phagocyte host defense, generating vigorous but finite antibacterial responses. we investigated the fate of highly purified primary human monocytes following phagocytosis of different bacteria. exposure to high bacterial loads resulted in rapid loss of cell viability and decreased functional competence. cell death typically involved classical apoptosis. exposure to high numbers of escherichia coli and klebsiella pne ... | 2010 | 20656927 |
| characterization and pcr-based replicon typing of resistance plasmids in acinetobacter baumannii. | acinetobacter baumannii is an opportunistic pathogen, especially in intensive care units, and multidrug-resistant isolates have increasingly been reported during the last decade. despite recent progress in knowledge of antibiotic resistance mechanisms in a. baumannii, little is known about the genetic factors driving isolates toward multidrug resistance. in the present study, the a. baumannii plasmids were investigated through the analysis and classification of plasmid replication systems and th ... | 2010 | 20660691 |
| the influence of genomics and proteomics on the development of potential vaccines against meningococcal infection. | abstract : there is a particular need for an effective vaccine against life-threatening meningitis and septicemia caused by neisseria meningitidis (meningococcus) serogroup b strains. vaccine strategies incorporating capsular polysaccharide have proved effective against other meningococcal serogroups, but are not applicable to serogroup b. attention has therefore focused on the subcapsular outer membrane protein antigens as potential vaccine components. the sequencing of genomes from three serog ... | 2010 | 20670394 |
| genome sequencing reveals widespread virulence gene exchange among human neisseria species. | commensal bacteria comprise a large part of the microbial world, playing important roles in human development, health and disease. however, little is known about the genomic content of commensals or how related they are to their pathogenic counterparts. the genus neisseria, containing both commensal and pathogenic species, provides an excellent opportunity to study these issues. we undertook a comprehensive sequencing and analysis of human commensal and pathogenic neisseria genomes. commensals h ... | 2010 | 20676376 |
| neisseria lactamica selectively induces mitogenic proliferation of the naive b cell pool via cell surface ig. | neisseria lactamica is a commensal bacteria that colonizes the human upper respiratory tract mucosa during early childhood. in contrast to the closely related opportunistic pathogen neisseria meningitidis, there is an absence of adaptive cell-mediated immunity to n. lactamica during the peak age of carriage. instead, outer membrane vesicles derived from n. lactamica mediate a b cell-dependent proliferative response in mucosal mononuclear cells that is associated with the production of polyclonal ... | 2010 | 20709949 |
| structural alterations in a component of cytochrome c oxidase and molecular evolution of pathogenic neisseria in humans. | three closely related bacterial species within the genus neisseria are of importance to human disease and health. neisseria meningitidis is a major cause of meningitis, while neisseria gonorrhoeae is the agent of the sexually transmitted disease gonorrhea and neisseria lactamica is a common, harmless commensal of children. comparative genomics have yet to yield clear insights into which factors dictate the unique host-parasite relationships exhibited by each since, as a group, they display remar ... | 2010 | 20808844 |
| prevalence of chlamydia infection among women visiting a gynaecology outpatient department: evaluation of an in-house pcr assay for detection of chlamydia trachomatis. | screening women for chlamydia trachomatis infection in developing countries is highly desirable because of asymptomatic infection. the existing diagnostic methods in developing countries are not effective and their sensitivity fall below 45.0% which leads to further spread of infection. there is an urgent need for improved and cost effective diagnostic tests that will reduce the burden of sexually transmitted infections in the developing world. | 2010 | 20822551 |
| human airway epithelial cell responses to neisseria lactamica and purified porin via toll-like receptor 2-dependent signaling. | the human airway epithelium is constantly exposed to microbial products from colonizing organisms. regulation of toll-like receptor (tlr) expression and specific interactions with bacterial ligands is thought to mitigate exacerbation of inflammatory processes induced by the commensal flora in these cells. the genus neisseria comprises pathogenic and commensal organisms that colonize the human nasopharynx. neisseria lactamica is not associated with disease, but n. meningitidis occasionally invade ... | 2010 | 20937766 |
| meningococcal internalization into human endothelial and epithelial cells is triggered by the influx of extracellular l-glutamate via gltt l-glutamate abc transporter in neisseria meningitidis. | meningococcal internalization into human cells is likely to be a consequence of meningococcal adhesion to human epithelial and endothelial cells. here, we identified three transposon mutants of neisseria meningitidis that were primarily defective in the internalization of human brain microvascular endothelial cells (hbmec), with insertions occurring in the gltt (a sodium-independent l-glutamate transporter) gene or its neighboring gene, nmb1964 (unknown function). nmb1964 was tentatively named g ... | 2010 | 20956569 |
| meningococcal internalization into human endothelial and epithelial cells is triggered by the influx of extracellular l-glutamate via gltt l-glutamate abc transporter in neisseria meningitidis. | meningococcal internalization into human cells is likely to be a consequence of meningococcal adhesion to human epithelial and endothelial cells. here, we identified three transposon mutants of neisseria meningitidis that were primarily defective in the internalization of human brain microvascular endothelial cells (hbmec), with insertions occurring in the gltt (a sodium-independent l-glutamate transporter) gene or its neighboring gene, nmb1964 (unknown function). nmb1964 was tentatively named g ... | 2010 | 20956569 |
| independent evolution of the core and accessory gene sets in the genus neisseria: insights gained from the genome of neisseria lactamica isolate 020-06. | the genus neisseria contains two important yet very different pathogens, n. meningitidis and n. gonorrhoeae, in addition to non-pathogenic species, of which n. lactamica is the best characterized. genomic comparisons of these three bacteria will provide insights into the mechanisms and evolution of pathogenesis in this group of organisms, which are applicable to understanding these processes more generally. | 2010 | 21092259 |
| neisseria lactamica attenuates tlr-1/2-induced cytokine responses in nasopharyngeal epithelial cells using ppar-γ. | the upper respiratory tract commensal neisseria lactamica (nlac) induces protective humoral immunity against pathogenic nmen serogroup b (nmen), but whether it also affords anti-inflammatory mucosal protection, as reported for several gut commensals, has not been investigated. here we demonstrate for the first time that nlac weakly induces inflammatory responses compared with nmen in the nasopharyngeal epithelial cell line, detroit 562, and that nlac achieves this by attenuation of secretory cyt ... | 2011 | 21105983 |
| nasopharyngeal colonization by neisseria lactamica and induction of protective immunity against neisseria meningitidis. | natural immunity to neisseria meningitidis may result from nasopharyngeal carriage of closely related commensals, such as neisseria lactamica. | 2011 | 21148522 |
| vaccine development against neisseria meningitidis. | meningococcal disease is communicable by close contact or droplet aerosols. striking features are high case fatality rates and peak incidences of invasive disease in infants, toddlers and adolescents. vaccine development is hampered by bacterial immune evasion strategies including molecular mimicry.as for haemophilus influenzae and streptococcus pneumoniae, no vaccine has therefore been developed that targets all serogroups of neisseria meningitidis. polysaccharide vaccines available both in pro ... | 2011 | 21255369 |
| vaccine development against neisseria meningitidis. | meningococcal disease is communicable by close contact or droplet aerosols. striking features are high case fatality rates and peak incidences of invasive disease in infants, toddlers and adolescents. vaccine development is hampered by bacterial immune evasion strategies including molecular mimicry.as for haemophilus influenzae and streptococcus pneumoniae, no vaccine has therefore been developed that targets all serogroups of neisseria meningitidis. polysaccharide vaccines available both in pro ... | 2011 | 21255369 |
| horizontal transfer, not duplication, drives the expansion of protein families in prokaryotes. | gene duplication followed by neo- or sub-functionalization deeply impacts the evolution of protein families and is regarded as the main source of adaptive functional novelty in eukaryotes. while there is ample evidence of adaptive gene duplication in prokaryotes, it is not clear whether duplication outweighs the contribution of horizontal gene transfer in the expansion of protein families. we analyzed closely related prokaryote strains or species with small genomes (helicobacter, neisseria, stre ... | 2011 | 21298028 |
| quantification of ploidy in proteobacteria revealed the existence of monoploid, (mero-)oligoploid and polyploid species. | bacteria are generally assumed to be monoploid (haploid). this assumption is mainly based on generalization of the results obtained with the most intensely studied model bacterium, escherichia coli (a gamma-proteobacterium), which is monoploid during very slow growth. however, several species of proteobacteria are oligo- or polyploid, respectively. to get a better overview of the distribution of ploidy levels, genome copy numbers were quantified in four species of three different groups of prote ... | 2011 | 21305010 |
| first report of performance of the versant ct/gc dna 1.0 assay (kpcr) for detection of chlamydia trachomatis and neisseria gonorrhoeae. | we evaluated the analytical, work flow, and clinical performance of the versant ct/gc dna 1.0 assay (versant ct/gc assay, where "ct" represents chlamydia trachomatis and "gc" represents neisseria gonorrhoeae). the assay simultaneously detects chlamydia trachomatis and neisseria gonorrhoeae in swab and first-catch urine (fcu) specimens. the limit of detection (lod) was determined to be 342 copies/ml for c. trachomatis and 137 copies/ml for gc. the versant ct/gc assay detected 15 c. trachomatis se ... | 2011 | 21307209 |
| cooperative role for tetraspanins in adhesin-mediated attachment of bacterial species to human epithelial cells. | the tetraspanins are a superfamily of transmembrane proteins with diverse functions and can form extended microdomains within the plasma membrane in conjunction with partner proteins, which probably includes receptors for bacterial adhesins. neisseria meningitidis, the causative agent of meningococcal disease, attaches to host nasopharyngeal epithelial cells via type iv pili and opacity (opa) proteins. we examined the role of tetraspanin function in neisseria meningitidis adherence to epithelial ... | 2011 | 21464080 |
| characterization of neisseria meningitidis isolates that do not express the virulence factor and vaccine antigen factor h binding protein. | neisseria meningitidis remains a leading cause of bacterial sepsis and meningitis. complement is a key component of natural immunity against this important human pathogen, which has evolved multiple mechanisms to evade complement-mediated lysis. one approach adopted by the meningococcus is to recruit a human negative regulator of the complement system, factor h (fh), to its surface via a lipoprotein, factor h binding protein (fhbp). additionally, fhbp is a key antigen in vaccines currently being ... | 2011 | 21508163 |
| genetic and molecular analyses reveal an evolutionary trajectory for glycan synthesis in a bacterial protein glycosylation system. | although protein glycosylation systems are becoming widely recognized in bacteria, little is known about the mechanisms and evolutionary forces shaping glycan composition. species within the genus neisseria display remarkable glycoform variability associated with their o-linked protein glycosylation (pgl) systems and provide a well developed model system to study these phenomena. by examining the potential influence of two orfs linked to the core pgl gene locus, we discovered that one of these, ... | 2011 | 21606362 |
| francisella tularensis molecular typing using differential insertion sequence amplification (disa). | tularemia is a potentially fatal disease that is caused by the highly infectious and zoonotic pathogen francisella tularensis. despite the monomorphic nature of sequenced f. tularensis genomes, there is a significant degree of plasticity in the organization of genetic elements. the observed variability in these genomes is primarily due to the transposition of direct repeats and insertion sequence (is) elements. since current methods used to genotype f. tularensis are time-consuming and require e ... | 2011 | 21613430 |
| using snps to discriminate disease associated from carried genomes of neisseria meningitidis. | neisseria meningitidis is one of the main agents of bacterial meningitis causing substantial morbidity and mortality worldwide. however, most of the time n. meningitidis is carried as a commensal not associated with invasive disease. the genomic basis of the difference between disease associated versus carried isolates of n. meningitidis may provide critical insight into mechanisms of virulence, yet it has remained elusive. here, we have taken a comparative genomics approach to interrogate the d ... | 2011 | 21622743 |
| neisserial omp85 protein is selectively recognized and assembled into functional complexes in the outer membrane of human mitochondria. | as a consequence of their bacterial origin, mitochondria contain β-barrel proteins in their outer membrane (omm). these proteins require the translocase of the outer membrane (tom) complex and the conserved sorting and assembly machinery (sam) complex for transport and integration into the omm. the sam complex and the β-barrel assembly machinery (bam) required for biogenesis of β-barrel proteins in bacteria are evolutionarily related. despite this homology, we show that bacterial β-barrel protei ... | 2011 | 21652692 |
| evaluation of six commercial nucleic acid amplification tests for the detection of neisseria gonorrhoeae and other neisseria species. | molecular detection of neisseria gonorrhoeae in extragenital samples may result in false positive results due to cross reaction with commensal neisseria species or neisseria meningitidis. this study examined 450 characterised clinical culture isolates, comprising 216 n. gonorrhoeae and 234 neisseria species (n=218) and other closely related bacteria (n=16), with six commercial nucleic acid amplification tests (naats) including gen-probe aptima combo 2 and aptima gc; roche cobas amplicor ct/ng an ... | 2011 | 21813721 |
| from pertussis to meningococcal disease and back. | from pertussis to meningococcal disease and back represents nearly 30 years of research at porton, first at the centre for applied microbiology and research and latterly as part of the health protection agency. i joined the group lead by andy robinson developing an acellular pertussis vaccine and was part of an exciting period that encompassed basic antigen characterisation and pathogenesis studies with the development of an acellular vaccine containing fimbriae. research then changed to focus o ... | 2011 | 21795847 |
| incorporation of real-time pcr into routine public health surveillance of culture negative bacterial meningitis in s+úo paulo, brazil. | real-time (rt)-pcr increases diagnostic yield for bacterial meningitis and is ideal for incorporation into routine surveillance in a developing country. we validated a multiplex rt-pcr assay for streptococcus pneumoniae, neisseria meningitidis, and haemophilus influenzae in brazil. risk factors for being culture-negative, rt-pcr positive were determined. the sensitivity of rt-pcr in cerebrospinal fluid (csf) was 100% (95% confidence limits, 96.0%-100%) for n. meningitidis, 97.8% (85.5%-99.9%) fo ... | 2011 | 21731621 |
| human lipooligosaccharide igg that prevents endemic meningococcal disease recognizes an internal lacto-n-neotetraose structure. | antibodies that initiate complement-mediated killing of neisseria meningitidis as they enter the bloodstream from the oropharynx protect against disseminated disease. human iggs that bind the neisserial l7 lipooligosaccharide (los) are bactericidal for l3,7 and l2,4 meningococci in the presence of human complement. these strains share a lacto-n-neotetraose (nlc4) los α chain. we used a set of mutants that have successive saccharide deletions from the nlc4 α chain to characterize further the bind ... | 2011 | 22027827 |
| Development of a Multiplex PCR Assay for Detection and Genogrouping of Neisseria meningitidis. | Neisseria meningitidis is a leading pathogen of epidemic bacterial meningitis and fulminant sepsis worldwide. Twelve different N. meningitidis serogroups have been identified to date based on antigenic differences in the capsular polysaccharide. However, more than 90% of human cases of N. meningitidis meningitis are the result of infection with just five serogroups, A, B, C, W135, and Y. Efficient methods of detection and genogrouping of N. meningitidis isolates are needed, therefore, in order t ... | 2012 | 22090406 |
| Population structure in the Neisseria, and the biological significance of fuzzy species. | Phenotypic and genetic variation in bacteria can take bewilderingly complex forms even within a single genus. One of the most intriguing examples of this is the genus Neisseria, which comprises both pathogens and commensals colonizing a variety of body sites and host species, and causing a range of disease. Complex relatedness among both named species and previously identified lineages of Neisseria makes it challenging to study their evolution. Using the largest publicly available collection of ... | 2011 | 22072450 |
| Population structure in the Neisseria, and the biological significance of fuzzy species. | Phenotypic and genetic variation in bacteria can take bewilderingly complex forms even within a single genus. One of the most intriguing examples of this is the genus Neisseria, which comprises both pathogens and commensals colonizing a variety of body sites and host species, and causing a range of disease. Complex relatedness among both named species and previously identified lineages of Neisseria makes it challenging to study their evolution. Using the largest publicly available collection of ... | 2011 | 22072450 |
| Rapid PCR detection of group A streptococcus from flocked throat swabs: a retrospective clinical study. | Rapid diagnosis of GAS pharyngitis may improve patient care by ensuring that patients with GAS pharyngitis are treated quickly and also avoiding unnecessary use of antibiotics in those without GAS infection. Very few molecular methods for detection of GAS in clinical throat swab specimens have been described. | 2011 | 21888649 |
| pathogenic neisseria hitchhike on the uropod of human neutrophils. | polymorphonuclear neutrophils (pmns) are important components of the human innate immune system and are rapidly recruited at the site of bacterial infection. despite the effective phagocytic activity of pmns, neisseria gonorrhoeae infections are characterized by high survival within pmns. we reveal a novel type iv pilus-mediated adherence of pathogenic neisseria to the uropod (the rear) of polarized pmns. the direct pilus-uropod interaction was visualized by scanning electron microscopy and tota ... | 2011 | 21949708 |
| haemophilus influenzae type b carriage among young children in metropolitan atlanta in the context of vaccine shortage and booster dose deferral. | short-term deferral of the haemophilus influenzae type b (hib) vaccine booster dose during a recent u.s. hib vaccine shortage did not result in widespread hib carriage in atlanta, as the hib carriage rate was found to be 0.3% (1/342). hib colonization was significantly more common among males and day care attendees. | 2011 | 22012977 |
| Distinct Roles of ß-Galactosidase Paralogues of the Rumen Bacterium Mannheimia succiniciproducens. | Mannheimia succiniciproducens, a rumen bacterium belonging to the family Pasteurellaceae, has two putative ß-galactosidase genes, bgaA and bgaB, encoding polypeptides whose deduced amino acid sequences share 56% identity with each other and show approximately 30% identity to the Escherichia coli gene for LacZ. The M. succiniciproducens bgaA (MsbgaA) gene-deletion mutant was not able to grow on lactose as the sole carbon source, suggesting its essential role in lactose metabolism, whereas the Msb ... | 2012 | 22081396 |
| neisserial correia repeat-enclosed elements do not influence the transcription of pil genes in neisseria gonorrhoeae and neisseria meningitidis. | two human-specific neisserial pathogens, neisseria gonorrhoeae and neisseria meningitidis, require the expression of type iv pili (tfp) for initial attachment to the host during infection. however, the mechanisms controlling the assembly and functionality of tfp are poorly understood. it is known that the gonococcal pile gene, encoding the major subunit, is positively regulated by ihf, a multifunctional dna binding protein. a neisserial specific repetitive dna sequence, termed the correia repeat ... | 2011 | 21856854 |
| implementation and impact of a meningococcal c conjugate vaccination program in 13- to 25-year-old individuals in galicia, spain. | background: in response to increased case numbers of meningococcal group c disease, catch-up vaccination strategies have been shown to be successful. this paper describes the results of a repeat vaccination program in galicia, spain, and the strategy used for it. methods and results: three vaccination waves were performed: first, in 1996/1997 with a meningococcal group a and c polysaccharide vaccine in individuals aged 18 months to 19 years; second, in 2000 with a conjugate serogroup c polysacc ... | 2011 | 21957332 |
| changes in serogroup and genotype prevalence among carried meningococci in the united kingdom during vaccine implementation. | herd immunity is important in the effectiveness of conjugate polysaccharide vaccines against encapsulated bacteria. a large multicenter study investigated the effect of meningococcal serogroup c conjugate vaccine introduction on the meningococcal population. | 2011 | 21881120 |
| horizontal gene transfer in histophilus somni and its role in the evolution of pathogenic strain 2336, as determined by comparative genomic analyses. | abstract: background: pneumonia and myocarditis are the most commonly reported diseases due to histophilus somni, an opportunistic pathogen of the reproductive and respiratory tracts of cattle. thus far only a few genes involved in metabolic and virulence functions have been identified and characterized in h. somni using traditional methods. analyses of the genome sequences of several pasteurellaceae species have provided insights into their biology and evolution. in view of the economic and ec ... | 2011 | 22111657 |
| genome wide expression profiling reveals suppression of host defence responses during colonisation by neisseria meningitides but not n. lactamica. | both neisseria meningitidis and the closely related bacterium neisseria lactamica colonise human nasopharyngeal mucosal surface, but only n. meningitidis invades the bloodstream to cause potentially life-threatening meningitis and septicaemia. we have hypothesised that the two neisserial species differentially modulate host respiratory epithelial cell gene expression reflecting their disease potential. confluent monolayers of 16hbe14 human bronchial epithelial cells were exposed to live and/or d ... | 2011 | 22028815 |
| microbial antigenic variation mediated by homologous dna recombination. | pathogenic microorganisms employ numerous molecular strategies in order to delay or circumvent recognition by the immune system of their host. one of the most widely used strategies of immune evasion is antigenic variation, in which immunogenic molecules expressed on the surface of a microorganism are continuously modified. as a consequence, the host is forced to constantly adapt its humoral immune response against this pathogen. an antigenic change thus provides the microorganism with an opport ... | 2011 | 22212019 |
| [congenital skull base defect causing recurrent bacterial meningitis]. | bacterial meningitis is a life threatening disease. most patients will experience only one episode throughout life. children who experience bacterial meningitis more than once, require further immunologic or anatomic evaluation. we report a 9 year old child with five episodes of bacterial meningitis due to a congenital defect of the skull base. a two and a half year old boy first presented to our medical center with pneumococcal meningitis. he was treated with antibiotics and fully recovered. tw ... | 2012 | 23350293 |
| a multiplexed microfluidic pcr assay for sensitive and specific point-of-care detection of chlamydia trachomatis. | chlamydia trachomatis (ct) is the most common cause of bacterial sexually transmitted diseases (std) worldwide. while commercial nucleic acid amplification tests (naat) are available for ct, none are rapid or inexpensive enough to be used at the point-of-care (poc). towards the first ct poc naat, we developed a microfluidic assay that simultaneously interrogates nine ct loci in 20 minutes. | 2012 | 23272140 |
| growth inhibition of pathogenic bacteria by sulfonylurea herbicides. | emerging resistance to current antibiotics raises the need for new microbial drug targets. we show that targeting branched-chain amino acid (bcaa) biosynthesis using sulfonylurea herbicides, which inhibit the bcaa biosynthetic enzyme acetohydroxyacid synthase (ahas), can exert bacteriostatic effects on several pathogenic bacteria, including burkholderia pseudomallei, pseudomonas aeruginosa, and acinetobacter baumannii. our results suggest that targeting biosynthetic enzymes like ahas, which are ... | 2012 | 23263008 |
| various pathways leading to the acquisition of antibiotic resistance by natural transformation. | natural transformation can lead to exchange of dna between taxonomically diverse bacteria. in the case of chromosomal dna, homology-based recombination with the recipient genome is usually necessary for heritable stability. in our recent study, we have shown that natural transformation can promote the transfer of transposons, is elements, and integrons and gene cassettes, largely independent of the genetic relationship between the donor and recipient bacteria. additional results from our study s ... | 2012 | 23482877 |
| rapid universal identification of bacterial pathogens from clinical cultures by using a novel sloppy molecular beacon melting temperature signature technique. | a real-time pcr assay with the ability to rapidly identify all pathogenic bacteria would have widespread medical utility. current real-time pcr technologies cannot accomplish this task due to severe limitations in multiplexing ability. to this end, we developed a new assay system which supports very high degrees of multiplexing. we developed a new class of mismatch-tolerant "sloppy" molecular beacons, modified them to provide an extended hybridization range, and developed a multiprobe, multimelt ... | 2009 | 19923485 |
| rapid universal identification of bacterial pathogens from clinical cultures by using a novel sloppy molecular beacon melting temperature signature technique. | a real-time pcr assay with the ability to rapidly identify all pathogenic bacteria would have widespread medical utility. current real-time pcr technologies cannot accomplish this task due to severe limitations in multiplexing ability. to this end, we developed a new assay system which supports very high degrees of multiplexing. we developed a new class of mismatch-tolerant "sloppy" molecular beacons, modified them to provide an extended hybridization range, and developed a multiprobe, multimelt ... | 2009 | 19923485 |
| outer membrane vesicles as platform vaccine technology. | outer membrane vesicles (omvs) are released spontaneously during growth by many gram-negative bacteria. they present a range of surface antigens in a native conformation and have natural properties like immunogenicity, self-adjuvation and uptake by immune cells which make them attractive for application as vaccines against pathogenic bacteria. in particular with neisseria meningitidis, they have been investigated extensively and an omv-containing meningococcal vaccine has recently been approved ... | 2015 | 26912077 |
| evolutionary switches between two serine codon sets are driven by selection. | serine is the only amino acid that is encoded by two disjoint codon sets so that a tandem substitution of two nucleotides is required to switch between the two sets. previously published evidence suggests that, for the most evolutionarily conserved serines, the codon set switch occurs by simultaneous substitution of two nucleotides. here we report a genome-wide reconstruction of the evolution of serine codons in triplets of closely related species from diverse prokaryotes and eukaryotes. the res ... | 2016 | 27799560 |
| identification of novel immunogenic proteins of neisseria gonorrhoeae by phage display. | neisseria gonorrhoeae is one of the most prevalent sexually transmitted diseases worldwide with more than 100 million new infections per year. a lack of intense research over the last decades and increasing resistances to the recommended antibiotics call for a better understanding of gonococcal infection, fast diagnostics and therapeutic measures against n. gonorrhoeae. therefore, the aim of this work was to identify novel immunogenic proteins as a first step to advance those unresolved problems ... | 2016 | 26859666 |
| antigenic variation in bacterial pathogens. | antigenic variation is a strategy used by a broad diversity of microbial pathogens to persist within the mammalian host. whereas viruses make use of a minimal proofreading capacity combined with large amounts of progeny to use random mutation for variant generation, antigenically variant bacteria have evolved mechanisms which use a stable genome, which aids in protecting the fitness of the progeny. here, three well-characterized and highly antigenically variant bacterial pathogens are discussed: ... | 2016 | 26999387 |
| identification of a unique tlr2-interacting peptide motif in a microbial leucine-rich repeat protein. | pathogenesis of many bacterially-induced inflammatory diseases is driven by toll-like receptor (tlr) mediated immune responses following recognition of bacterial factors by different tlrs. periodontitis is a chronic inflammation of the tooth supporting apparatus often leading to tooth loss, and is caused by a gram-negative bacterial consortium that includes tannerella forsythia. this bacterium expresses a virulence factor, the bspa, which drives periodontal inflammation by activating tlr2. the n ... | 2012 | 22695115 |
| patient-specific analysis of periodontal and peri-implant microbiomes. | periodontally involved teeth have been implicated as 'microbial reservoirs' in the etiology of peri-implant diseases. therefore, the purpose of this investigation was to use a deep-sequencing approach to identify the degree of congruence between adjacent peri-implant and periodontal microbiomes in states of health and disease. subgingival and peri-implant biofilm samples were collected from 81 partially edentulous individuals with periodontal and peri-implant health and disease. bacterial dna wa ... | 2013 | 24158341 |
| molecular mapping to species level of the tonsillar crypt microbiota associated with health and recurrent tonsillitis. | the human palatine tonsils, which belong to the central antigen handling sites of the mucosal immune system, are frequently affected by acute and recurrent infections. this study compared the microbiota of the tonsillar crypts in children and adults affected by recurrent tonsillitis with that of healthy adults and children with tonsillar hyperplasia. an in-depth 16s rrna gene based pyrosequencing approach combined with a novel strategy that included phylogenetic analysis and detection of species ... | 2013 | 23437130 |
| differential distribution of type ii crispr-cas systems in agricultural and nonagricultural campylobacter coli and campylobacter jejuni isolates correlates with lack of shared environments. | crispr (clustered regularly interspaced palindromic repeats)-cas (crispr-associated) systems are sequence-specific adaptive defenses against phages and plasmids which are widespread in prokaryotes. here we have studied whether phylogenetic relatedness or sharing of environmental niches affects the distribution and dissemination of type ii crispr-cas systems, first in 132 bacterial genomes from 15 phylogenetic classes, ranging from proteobacteria to actinobacteria. there was clustering of distinc ... | 2015 | 26338188 |
| the influence of smoking on the peri-implant microbiome. | smokers are at high risk for 2 bacterially driven oral diseases: peri-implant mucositis and peri-implantitis. therefore, the purpose of this investigation was to use a deep-sequencing approach to identify the effect of smoking on the peri-implant microbiome in states of health and disease. peri-implant biofilm samples were collected from 80 partially edentulous subjects with peri-implant health, peri-implant mucositis, and peri-implantitis. bacterial dna was isolated and 16s ribsomal rna gene li ... | 2015 | 26124222 |
| long-term evaluation of the antimicrobial susceptibility and microbial profile of subgingival biofilms in individuals with aggressive periodontitis. | this study evaluates the antimicrobial susceptibility and composition of subgingival biofilms in generalized aggressive periodontitis (gap) patients treated using mechanical/antimicrobial therapies, including chlorhexidine (chx), amoxicillin (amx) and metronidazole (met). gap patients allocated to the placebo (c, n = 15) or test group (t, n = 16) received full-mouth disinfection with chx, scaling and root planning, and systemic amx (500 mg)/met (250 mg) or placebos. subgingival plaque samples we ... | 2015 | 26273264 |
| dna microarray characterization of pathogens associated with sexually transmitted diseases. | this study established a multiplex pcr-based microarray to detect simultaneously a diverse panel of 17 sexually transmitted diseases (stds)-associated pathogens including neisseria gonorrhoeae, chlamydia trachomatis, mycoplasma genitalium, mycoplasma hominis, ureaplasma, herpes simplex virus (hsv) types 1 and 2, and human papillomavirus (hpv) types 6, 11, 16, 18, 31, 33, 35, 39, 54 and 58. the target genes are 16s rrna gene for n. gonorrhoeae, m. genitalium, m. hominism, and ureaplasma, the majo ... | 2015 | 26208181 |
| the mmei family: type ii restriction-modification enzymes that employ single-strand modification for host protection. | the type ii restriction endonucleases form one of the largest families of biochemically-characterized proteins. these endonucleases typically share little sequence similarity, except among isoschizomers that recognize the same sequence. mmei is an unusual type ii restriction endonuclease that combines endonuclease and methyltransferase activities in a single polypeptide. mmei cuts dna 20 bases from its recognition sequence and modifies just one dna strand for host protection. using mmei as query ... | 2009 | 19578066 |
| functional genes to assess nitrogen cycling and aromatic hydrocarbon degradation: primers and processing matter. | targeting sequencing to genes involved in key environmental processes, i.e., ecofunctional genes, provides an opportunity to sample nature's gene guilds to greater depth and help link community structure to process-level outcomes. vastly different approaches have been implemented for sequence processing and, ultimately, for taxonomic placement of these gene reads. the overall quality of next generation sequence analysis of functional genes is dependent on multiple steps and assumptions of unknow ... | 2013 | 24062736 |
| evolution and comparative genomics of campylobacter jejuni st-677 clonal complex. | campylobacter is the most common bacterial cause of gastroenteritis in the european union with over 200,000 laboratory-confirmed cases reported annually. this is the first study to describe findings related to comparative genomics analyses of the sequence type (st)-677 clonal complex (cc), a campylobacter jejuni lineage associated with bacteremia cases in humans. we performed whole-genome sequencing, using illumina hiseq sequencing technology, on five related st-677 cc isolates from two chicken ... | 2014 | 25193305 |
| hypomorphic glycosyltransferase alleles and recoding at contingency loci influence glycan microheterogeneity in the protein glycosylation system of neisseria species. | as more bacterial protein glycosylation systems are identified and characterized, a central question that arises is, what governs the prevalence of particular glycans associated with them? in addition, accumulating evidence shows that bacterial protein glycans can be subject to the phenomenon of microheterogeneity, in which variant glycan structures are found at specific attachment sites of a given glycoprotein. although factors underlying microheterogeneity in reconstituted expression systems h ... | 2012 | 22797763 |
| antimicrobial activities of fidaxomicin. | fidaxomicin is bactericidal against clostridium difficile. the combined results of 8 in vitro studies of 1323 c. difficile isolates showed the minimum inhibitory concentration (mic) range of fidaxomicin to be ≤ 0.001-1 μg/ml, with a maximum mic for inhibition of 90% of organisms (mic(90)) of 0.5 μg/ml. isolates from 2 phase iii clinical trials demonstrated that fidaxomicin mics of baseline isolates did not predict clinical cure, failure, or recurrence of c. difficile infections. no resistance to ... | 2012 | 22752863 |
| allelic variation in a simple sequence repeat element of neisserial pglb2 and its consequences for protein expression and protein glycosylation. | neisseria species express an o-linked glycosylation system in which functionally distinct proteins are elaborated with variable glycans. a major source of glycan diversity in n. meningitidis results from two distinct pglb alleles responsible for the synthesis of either n,n'-diacetylbacillosamine or glyceramido-acetamido trideoxyhexose that occupy the reducing end of the oligosaccharides. alternative modifications at c-4 of the precursor udp-4-amino are attributable to distinct c-terminal domains ... | 2013 | 23729645 |
| rapid pcr detection of mycoplasma hominis, ureaplasma urealyticum, and ureaplasma parvum. | objective. we compared laboratory developed real-time pcr assays for detection of mycoplasma hominis and for detection and differentiation of ureaplasma urealyticum and parvum to culture using genitourinary specimens submitted for m. hominis and ureaplasma culture. methods. 283 genitourinary specimens received in the clinical bacteriology laboratory for m. hominis and ureaplasma species culture were evaluated. nucleic acids were extracted using the total nucleic acid kit on the magna pure 2.0. 5 ... | 2013 | 26904723 |
| the dam replacing gene product enhances neisseria gonorrhoeae fa1090 viability and biofilm formation. | many neisseriaceae do not exhibit dam methyltransferase activity and, instead of the dam gene, possess drg (dam replacing gene) inserted in the leus/dam locus. the drg locus in neisseria gonorrhoeae fa1090 has a lower gc-pairs content (40.5%) compared to the whole genome of n. gonorrhoeae fa1090 (52%). the gonococcal drg gene encodes a dna endonuclease drg, with gmeatc specificity. disruption of drg or insertion of the dam gene in gonococcal genome changes the level of expression of genes as sho ... | 2014 | 25566225 |
| cas9-based tools for targeted genome editing and transcriptional control. | development of tools for targeted genome editing and regulation of gene expression has significantly expanded our ability to elucidate the mechanisms of interesting biological phenomena and to engineer desirable biological systems. recent rapid progress in the study of a clustered, regularly interspaced short palindromic repeat (crispr)/crispr-associated (cas) protein system in bacteria has facilitated the development of newly facile and programmable platforms for genome editing and transcriptio ... | 2014 | 24389925 |
| the capricious nature of bacterial pathogens: phasevarions and vaccine development. | infectious diseases are a leading cause of morbidity and mortality worldwide, and vaccines are one of the most successful and cost-effective tools for disease prevention. one of the key considerations for rational vaccine development is the selection of appropriate antigens. antigens must induce a protective immune response, and this response should be directed to stably expressed antigens so the target microbe can always be recognized by the immune system. antigens with variable expression, due ... | 2016 | 28018352 |
| multiplex assay for simultaneous detection of mycoplasma genitalium and macrolide resistance using plexzyme and plexprime technology. | mycoplasma genitalium is a cause of non-gonoccocal urethritis (ngu) in men and cervicitis and pelvic inflammatory disease in women. recent international data also indicated that the first line treatment, 1 gram stat azithromycin therapy, for m. genitalium is becoming less effective, with the corresponding emergence of macrolide resistant strains. increasing failure rates of azithromycin for m. genitalium has significant implications for the presumptive treatment of ngu and international clinical ... | 2016 | 27271704 |
| comprehensive laboratory evaluation of a highly specific lateral flow assay for the presumptive identification of bacillus anthracis spores in suspicious white powders and environmental samples. | we conducted a comprehensive, multiphase laboratory evaluation of the anthrax biothreat alert(®) test strip, a lateral flow immunoassay (lfa) for the rapid detection of bacillus anthracis spores. the study, conducted at 2 sites, evaluated this assay for the detection of spores from the ames and sterne strains of b. anthracis, as well as those from an additional 22 strains. phylogenetic near neighbors, environmental background organisms, white powders, and environmental samples were also tested. ... | 2016 | 27661796 |
| description of an unusual neisseria meningitidis isolate containing and expressing neisseria gonorrhoeae-specific 16s rrna gene sequences. | an apparently rare neisseria meningitidis isolate containing one copy of a neisseria gonorrhoeae 16s rrna gene is described herein. this isolate was identified as n. meningitidis by biochemical identification methods but generated a positive signal with gen-probe aptima assays for the detection of neisseria gonorrhoeae. direct 16s rrna gene sequencing of the purified isolate revealed mixed bases in signature regions that allow for discrimination between n. meningitidis and n. gonorrhoeae. the mi ... | 2013 | 23863567 |
| where does neisseria acquire foreign dna from: an examination of the source of genomic and pathogenic islands and the evolution of the neisseria genus. | pathogenicity islands (pais) or genomic islands (geis) are considered to be the result of a recent horizontal transfer. detecting pais/geis as well as their putative source can provide insight into the organism's pathogenicity within its host. previously we introduced a tool called s-plot which provides a visual representation of the variation in compositional properties across and between genomic sequences. utilizing s-plot and new functionality developed here, we examined 18 publicly available ... | 2013 | 24007216 |
| commensal streptococcus salivarius modulates pparγ transcriptional activity in human intestinal epithelial cells. | the impact of commensal bacteria in eukaryotic transcriptional regulation has increasingly been demonstrated over the last decades. a multitude of studies have shown direct effects of commensal bacteria from local transcriptional activity to systemic impact. the commensal bacterium streptococcus salivarius is one of the early bacteria colonizing the oral and gut mucosal surfaces. it has been shown to down-regulate nuclear transcription factor (nf-кb) in human intestinal cells, a central regulato ... | 2015 | 25946041 |
| automatic identification of species-specific repetitive dna sequences and their utilization for detecting microbial organisms. | the concentration of pathogen dna in biological samples is often very low. therefore, the sensitivity of diagnostic tests is always a critical factor. | 2009 | 19357101 |
| association of targeted multiplex pcr with resequencing microarray for the detection of multiple respiratory pathogens. | a large number of viral and bacterial organisms are responsible for community-acquired pneumonia (cap) which contributes to substantial burden on health management. a new resequencing microarray (rpm-ivdc1) associated with targeted multiplex pcr was recently developed and validated for multiple respiratory viruses detection and discrimination. in this study, we evaluated the capability of rpm-ivdc1 for simultaneous identification of multiple viral and bacterial organisms. the nasopharyngeal aspi ... | 2015 | 26074910 |
| trypanosoma cruzi differentiates and multiplies within chimeric parasitophorous vacuoles in macrophages coinfected with leishmania amazonensis. | the trypanosomatids leishmania amazonensis and trypanosoma cruzi are excellent models for the study of the cell biology of intracellular protozoan infections. after their uptake by mammalian cells, the parasitic protozoan flagellates l. amazonensis and t. cruzi lodge within acidified parasitophorous vacuoles (pvs). however, whereas l. amazonensis develops in spacious, phagolysosome-like pvs that may enclose numerous parasites, t. cruzi is transiently hosted within smaller vacuoles from which it ... | 2016 | 26975994 |