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analysis of emergence of quinolone-resistant gonococci in greece by combined use of neisseria gonorrhoeae multiantigen sequence typing and multilocus sequence typing.the prevalence of quinolone-resistant neisseria gonorrhoeae (qrng) in greece remained low from 1997 to 2003 but increased dramatically from 11% to 56% between 2004 and 2007. n. gonorrhoeae multiantigen sequence typing (ng-mast) and multilocus sequence typing (mlst) were used to investigate trends in quinolone resistance from 1997 to 2007 and explore the origins of the recent increase in qrng. we characterized 295 qrng isolates from the study period and 233 quinolone-susceptible (qs) gonococci fr ...201121248096
a vaccine against meningitis in africa. 201121183138
a phase 1 study of a meningococcal native outer membrane vesicle vaccine made from a group b strain with deleted lpxl1 and synx, over-expressed factor h binding protein, two poras and stabilized opca expression.this phase i clinical trial assessed the safety and immunogenicity of a native outer membrane vesicle (nomv) vaccine prepared from an lpxl1(-) synx(-) mutant of strain 8570(b:4:p1.19,15:l8-5) of neisseria meningitidis. additional mutations enhance the expression of factor h binding protein variant 1 (fhbp v.1), stabilize expression of opca and introduce a second pora (p1.22,14). thirty-six volunteers were assigned to one of four dose groups (10, 25, 50 and 75 mcg, based on protein content) to re ...201121199704
association between sexually transmitted diseases and young adults' self-reported abstinence.self-reported behavior has been the cornerstone of sexual health research and clinical practice, yet advances in sexually transmitted disease (std) screening provide researchers with the opportunity to objectively quantify sexual risk behaviors. however, the extent to which young adults' laboratory-confirmed std results and self-reported sexual behaviors are consistent has not been assessed in a nationally representative sample.201121199852
immunogenicity and safety of an investigational quadrivalent meningococcal acwy tetanus toxoid conjugate vaccine in healthy adolescents and young adults 10 to 25 years of age.an investigational quadrivalent neisseria meningitidis serogroups a, c, w-135, and y tetanus toxoid conjugate vaccine (menacwy-tt) has been developed to expand available options for vaccination against invasive meningococcal disease.201121200360
meningococcal glycoconjugate vaccines.neisseria meningitidis is a major cause of invasive bacterial infections worldwide. for this reason, efforts to control the disease have been directed at optimizing meningococcal vaccines and implementing appropriate vaccination policies. in the past, plain polysaccharide vaccines containing purified capsular polysaccharides a, c, y and w135 were developed, but failed to protect infants, who are at greatest risk. experience with the conjugate haemophilus vaccine suggested that this approach migh ...201121178398
prevalence of genital mycoplasma, ureaplasma, gardnerella, and human papillomavirus in japanese men with urethritis, and risk factors for detection of urethral human papillomavirus infection.to analyze the risk factors for hpv infection in the urethra, we examined the prevalence of various microorganisms, for example neisseria gonorrhoeae, chlamydia trachomatis, mycoplasma genitalium, mycoplasma hominis, ureaplasma urealyticum, ureaplasma parvum, gardnerella vaginalis, and human papillomavirus (hpv) in japanese male patients with urethritis, and investigated their sexual backgrounds. rubbed samples obtained from the distal urethra and questionnaires regarding sexual activity and dem ...201121213011
phosphatidylinositol 3'-kinase activity is critical for initiating the oxidative burst and bacterial destruction during ceacam3-mediated phagocytosis.carcinoembryonic antigen-related cell adhesion molecule 3 (ceacam3) is an immunoglobulin-related receptor expressed on human granulocytes. ceacam3 functions as a single chain phagocytotic receptor recognizing gram-negative bacteria such as neisseria gonorrhoeae, which possess ceacam-binding adhesins on their surface. the cytoplasmic domain of ceacam3 contains an immunoreceptor tyrosine-based activation motif (itam)-like sequence that is phosphorylated upon receptor engagement. here we show that ...201121216968
characterization of dsbd in neisseria meningitidis.proper periplasmic disulfide bond formation is important for folding and stability of many secreted and membrane proteins, and is catalysed by three dsba oxidoreductases in neisseria meningitidis. dsbd provides reducing power to dsbc that shuffles incorrect disulfide bond in misfolded proteins as well as to the periplasmic enzymes that reduce apo-cytochrome c (ccsx) or repair oxidative protein damages (mrsab). the expression of dsbd, but not other dsb genes, is positively regulated by the misr/s ...201121219471
a nasally administered trivalent inactivated influenza vaccine is well tolerated, stimulates both mucosal and systemic immunity, and potentially protects against influenza illness.a randomized placebo-controlled double-blind trial of a nasally administered inactivated trivalent influenza vaccine formulated with partially purified meningococcal outer membrane proteins (omp-tiv) was conducted in 1349 healthy adults aged 18-64 years. subjects received either vaccine containing 15 μg of haemagglutinin (ha) of each of three influenza strains for the 2003-2004 season on days 0 and 14, or 30 μg on day 0 and saline placebo on day 14, or placebo on days 0 and 14. vaccination was w ...201121219987
baseline meningococcal carriage in burkina faso before the introduction of a meningococcal serogroup a conjugate vaccine.the serogroup a meningococcal conjugate vaccine menafrivac has the potential to confer herd immunity by reducing carriage prevalence of epidemic strains. to better understand this phenomenon, we initiated a meningococcal carriage study to determine the baseline carriage rate and serogroup distribution before vaccine introduction in the 1- to 29-year old population in burkina faso, the group chosen for the first introduction of the vaccine. a multiple cross-sectional carriage study was conducted ...201121228139
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 ...201121255369
comparative analyses of the moraxella catarrhalis type-iv pilus structural subunit pila.moraxella catarrhalis is a gram-negative aerobic diplococcus that is a mucosal pathogen of the upper and lower respiratory tracts in humans. in order to colonize the human host and establish an infection, m. catarrhalis must be able to effectively attach to the respiratory mucosal epithelia. although little is known about m. catarrhalis pathogenesis, our laboratory has previously shown that expression of type iv pili (tfp) contributes to mucosal colonization. tfp are filamentous surface appendag ...201121256201
draft genome sequence of a dominant, multidrug-resistant neisseria gonorrhoeae strain, tcdc-ng08107, from a sexual group at high risk of acquiring human immunodeficiency virus infection and syphilis.neisseria gonorrhoeae infection is the second major cause of sexually transmitted diseases worldwide. development of resistance to multiple classes of antimicrobials in n. gonorrhoeae has compromised treatment and disease control. herein, we report the availability of the draft genome sequence of a multidrug-resistant n. gonorrhoeae isolate, tcdc-ng08107, which spread in groups of men who have sex with men (msm) in taiwan.201121257765
single nucleotide polymorphisms in tlr9 are highly associated with susceptibility to bacterial meningitis in children.bacterial meningitis (bm) is a severe infection mainly caused by streptococcus pneumoniae and neisseria meningitidis (nm). however, genetically determined susceptibility to develop severe infections by these microorganisms is variable between individuals. toll-like receptor 9 (tlr9) recognizes bacterial dna leading to intracellular inflammatory signaling. single nucleotide polymorphisms (snps) within the tlr9 gene are associated with susceptibility to several diseases, no such association with m ...201121258099
deep sequencing-based analysis of the anaerobic stimulon in neisseria gonorrhoeae.maintenance of an anaerobic denitrification system in the obligate human pathogen, neisseria gonorrhoeae, suggests that an anaerobic lifestyle may be important during the course of infection. furthermore, mounting evidence suggests that reduction of host-produced nitric oxide has several immunomodulary effects on the host. however, at this point there have been no studies analyzing the complete gonococcal transcriptome response to anaerobiosis. here we performed deep sequencing to compare the go ...201121251255
microbiological and epidemiological investigation of the neisseria meningitidis serogroup a epidemic in niger in 2009: last wave before the introduction of the serogroup a meningococcal conjugate vaccine?summarythe 2009 meningitis season in niger was characterized by an early onset, beginning in the very first weeks of the year and peaking from the 12th to the 15th week with 5655 clinical cases over the 4 weeks. from 1 january 2009 to 28 june 2009 (week 26), a total of 13 733 clinical cases of meningitis were reported to the national epidemiological surveillance system with a case-fatality rate of 4·2%. during the season 25 of the 42 health districts reached the epidemic threshold and 11 the ale ...201121251346
development and clinical validation of a loop-mediated isothermal amplification method for the rapid detection of neisseria meningitidis.loop-mediated isothermal amplification (lamp) is an innovative technique that allows the rapid detection of target nucleic acid sequences under isothermal conditions without the need for complex instrumentation. the development, optimization, and clinical validation of a lamp assay targeting the ctra gene for the rapid detection of capsular neisseria meningitidis were described. highly specific detection of capsular n. meningitidis type strains and clinical isolates was demonstrated, with no cro ...201121251556
detection of neisseria meningitidis in cerebrospinal fluid using a multiplex pcr and the luminex detection technology.rapid clinical and laboratory diagnoses are the foundation for a successful management of serious infections with neisseria meningitidis. a species-specific multiplex polymerase chain reaction (pcr) coupled with fluidic microarrays using microbeads (the luminex xmap™ technology) can detect pathogens most frequently found in the cerebrospinal fluid of patients. the luminex suspension array system uniquely combines flow cytometry, microspheres, laser technology, digital signal processing, and trad ...201221993638
periodic presumptive treatment of curable sexually transmitted infections among sex workers: recent experience with implementation.curable sexually transmitted infections (stis) are common occupational hazards for female sex workers in low-income and middle-income countries. yet, most infections are asymptomatic and sensitive screening tests are rarely affordable or feasible. periodic presumptive treatment (ppt) has been used as a component of sti control interventions to rapidly reduce sti prevalence.201222156895
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 ...201222090406
Antimicrobial resistance in sexually transmitted infections in the developed world: implications for rational treatment.Public health control of bacterial sexually transmitted infections (STIs) is dependent on the delivery of effective therapy and so will be compromised by the emergence of resistance. The scope of the problem and the implications for treatment that follow are discussed in this review.201222143116
expression, purification, and crystallization of neisserial outer membrane proteins.integral outer membrane proteins (omps) play key roles in solute transport, adhesion, and other processes. in neisseria, they can also function as major protective antigens. structural, biophysical, and immunological studies of neisserial omps require their isolation in milligram quantities. purification of any omp directly from neisseria would require the growth of large quantities of cell mass, with attendant concerns about safety and convenience. as a result, many investigators have developed ...201221993641
antigen dose escalation study of a vegf-based therapeutic cancer vaccine in non human primates.cigb-247 is a cancer therapeutic, based on recombinant modified human vascular endothelial growth factor (vegf) as antigen, in combination with the oil free adjuvant vssp (very small sized proteoliposomes of neisseria meningitidis outer membrane). our previous experimental studies in mice with cigb-247 have shown that the vaccine has both anti-tumoral and anti-metastatic activity, and produces both antibodies that block vegf-vegf receptor interaction, and a specific t-cell cytotoxic response aga ...201222075086
Determinants of the cytotoxicity of PrrC anticodon nuclease and its amelioration by tRNA repair.Breakage of tRNA(Lys(UUU)) by the Escherichia coli anticodon nuclease PrrC (EcoPrrC) underlies a host antiviral response to phage T4 infection that is ultimately thwarted by a virus-encoded RNA repair system. PrrC homologs are prevalent in other bacteria, but their activities and substrates are not defined. We find that induced expression of EcoPrrC is toxic in Saccharomyces cerevisiae and E. coli, whereas the Neisseria meningitidis PrrC (NmePrrC) is not. PrrCs consist of an N-terminal NTPase mo ...201222101242
Defining the Roles of Human Carcinoembryonic Antigen-Related Cellular Adhesion Molecules during Neutrophil Responses to Neisseria gonorrhoeae.Symptomatic infection of humans with Neisseria gonorrhoeae is characterized by a neutrophil-rich cervical or urethral exudate, suggesting that neutrophils are important both for the clearance of these bacteria and for the pathogenesis of gonorrhea. Neisseria interacts with neutrophils through ligation of human carcinoembryonic antigen related-cellular adhesion molecules (CEACAMs) by their surface-expressed Opa proteins, resulting in bacterial binding, engulfment, and neutrophil activation. Multi ...201222064717
antigen identification starting from the genome: a "reverse vaccinology" approach applied to menb.most of the vaccines available today, albeit very effective, have been developed using traditional "old-style" methodologies. technologies developed in recent years have opened up new perspectives in the field of vaccinology and novel strategies are now being used to design improved or new vaccines against infections for which preventive measures do not exist. the reverse vaccinology (rv) approach is one of the most powerful examples of biotechnology applied to the field of vaccinology for ident ...201221993656
In vivo imaging of meningococcal disease dynamics.Neisseria meningitidis is a human specific organism that causes severe sepsis and/or meningitis with high mortality. The disease scenario is rapid and much remains unknown about the disease process and host-pathogen interaction. In this chapter, we describe a protocol for generating a bioluminescently labeled N. meningitidis strain in order to advance our understanding of meningococcal disease progression. We also describe how in vivo bioluminescence imaging (BLI) can be used to observe novel fe ...201221993645
Novel Protein Substrates of the Phospho-Form Modification System in Neisseria gonorrhoeae and Their Connection to O-Linked Protein Glycosylation.The zwitterionic phospho-form moieties phosphoethanolamine (PE) and phosphocholine (PC) are important components of bacterial membranes and cell surfaces. The major type IV pilus subunit protein of Neisseria gonorrhoeae, PilE, undergoes posttranslational modifications with these moieties via the activity of the pilin phospho-form transferase PptA. A number of observations relating to colocalization of phospho-form and O-linked glycan attachment sites in PilE suggested that these modifications mi ...201222083701
in the nadr regulon, adhesins and diverse meningococcal functions are regulated in response to signals in human saliva.the neisseria meningitidis regulator nadr was shown to repress expression of the nada adhesin and play a major role in nada phase-variable expression. in this study, we identified through microarray analysis over 30 genes coregulated with nada in the nadr mutant and defined members of the nadr regulon through in vitro dna-binding assays. two distinct types of promoter architectures (i and ii) were identified for nadr targets, differing in both the number and position of nadr-binding sites. all n ...201222081399
neisseria meningitidis: biology, microbiology, and epidemiology.neisseria meningitidis (the meningococcus) causes significant morbidity and mortality in children and young adults worldwide through epidemic or sporadic meningitis and/or septicemia. in this review, we describe the biology, microbiology, and epidemiology of this exclusive human pathogen. n.meningitidis is a fastidious, encapsulated, aerobic gram-negative diplococcus. colonies are positive by the oxidase test and most strains utilize maltose. the phenotypic classification of meningococci, based ...201221993636
the use of the pan-neisseria microarray and experimental design for transcriptomics studies of neisseria.the pan-neisseria microarray was the first bacterial microarray to address multiple strains and species, and is a tool specifically developed for the performance of comparative studies within and between species. to achieve this, its design was based upon a detailed comparison of multiple genomes, prior to probe selection, and serial triage to optimize sensitivity and specificity. while this tool can be used for transcriptional comparisons of the same species, such as isogenic mutants, or strain ...201221993653
Hydrogen-deuterium exchange coupled to mass spectrometry to investigate ligand-receptor interactions.A method for exploring protein-protein interactions using hydrogen/deuterium exchange coupled to mass spectrometry is described. The method monitors the exchange of backbone (amide) hydrogens in solutions of deuterated water that primarily occur on portions of the protein exposed to solvent. In the presence of a protein binding partner, regions that experience reduced exchange are either part of the protein-protein interaction interface or undergo conformational changes to reduce accessibility t ...201221993650
Evaluation of Neisseria gonorrhoeae Multiple-Locus Variable-Number Tandem-Repeat Analysis, N. gonorrhoeae Multiantigen Sequence Typing, and Full-Length porB Gene Sequence Analysis for Molecular Epidemiological Typing.The performance characteristics of Neisseria gonorrhoeae multilocus variable-number tandem-repeat analysis were evaluated, by comparison with N. gonorrhoeae multiantigen sequence typing and full-length porB sequence typing. Assessment of the relatedness of intra- and interpatient isolates showed that all three genotyping techniques display a high resolution and typeability.201222075591
the slippery slope: lubricant use and rectal sexually transmitted infections: a newly identified risk.use of lubricant products is extremely common during receptive anal intercourse (rai) yet has not been assessed as a risk for acquisition of sexually transmitted infections (stis).201222183849
routine confirmation of positive nucleic acid amplification test results for neisseria gonorrhoeae is not necessary. 201222203751
Analysis of the immune response to Neisseria meningitidis using a proteomics approach.The availability of Neisseria genome sequences together with improvements in proteomic technologies provide the opportunity to study at high resolution the immune response to Neisseria meningitidis. In this chapter, we describe a protocol that combines two-dimensional (2D) SDS-PAGE of meningococcal outer membranes with western blotting of human antisera to identify proteins associated with the development of protective antibody responses. This methodology can identify putative vaccine candidates ...201221993655
high prevalence of sexually transmitted infections in hiv-infected men during routine outpatient visits in the netherlands.in the netherlands, no guidelines exist for routine sexually transmitted infection (sti) screening of human immunodeficiency virus (hiv)-infected men having sex with men (msm). we assessed prevalence and factors associated with asymptomatic sti.201222183837
a laminar-flow chamber assay for measuring bacterial adhesion under shear stress.shear stress levels generated by circulating blood have a strong impact on biological processes taking place in the vasculature. it is therefore important to take them into account when studying infectious agents targeting the endothelium. here we describe a protocol using disposable laminar-flow chambers and video microcopy to study bacterial infections in an environment that mimics the bloodstream. we initially focused on the interaction of neisseria meningitidis with human endothelial cells a ...201221993647
generating knock-out and complementation strains of neisseria meningitidis.the human-restricted pathogens neisseria meningitidis and neisseria gonorrhoeae are naturally competent for dna uptake. this trait has been exploited extensively for genetic manipulation of these bacteria in the laboratory. most transformation protocols were developed for n. gonorrhoeae, but appear to work also for n. meningitidis. in this chapter, we describe a number of protocols for genetic manipulation of n. meningitidis. specifically, we describe how to (1) obtain knock-out mutants containi ...201221993639
acoustic wave immunosensing of a meningococcal antigen using gold nanoparticle-enhanced mass sensitivity.bacterial meningitis is an infection of the thin membranes covering the brain and spinal cord by a number of microorganisms including neisseria meningitidis, which can lead to permanent neurological damage in the event of late diagnosis. given the quick onset and severity of the disease, there is a clear need for a rapid, sensitive and specific diagnostic technique. here, we describe the development and evaluation of an acoustic wave sensor, the quartz crystal microbalance (qcm), as a rapid immu ...201222104649
Prevalence of Neisseria gonorrhoeae Infections Among Men and Women Entering the National Job Training Program-United States, 2004-2009.: National notifiable disease data indicate that there were 99 cases of gonorrhea for every 100,000 persons in the United States in 2009, the lowest recorded gonorrhea rate in US history. However, the extent to which declining case reports signify a reduction in prevalence is unknown.201222183847
a dna vaccine strategy for effective antibody induction to pathogen-derived antigens.dna-based vaccines are currently being developed for treating a diversity of human diseases including cancers, autoimmune conditions, allergies, and microbial infections. in this chapter, we present a general protocol that can be used as a starting point for developing dna vaccines to pathogen-derived antigens, using neisseria meningitidis as an example. in addition, we describe a fusion gene-based vaccine protocol for increasing the potency of dna vaccines that are based on poorly immunogenic a ...201221993657
classification and pathogenesis of meningococcal infections.the clinical symptoms induced by neisseria meningitidis reflect compartmentalized intravascular and intracranial bacterial growth and inflammation. in this chapter, we describe a classification system for meningococcal disease based on the nature of the clinical symptoms. meningococci invade the subarachnoid space and cause meningitis in as many as 50-70% of patients. the bacteremic phase is moderate in patients with meningitis and mild systemic meningococcemia but graded high in patients with s ...201221993637
Techniques to measure pilus retraction forces.The importance of physical forces in biology is becoming more appreciated. Neisseria gonorrhoeaehas become a paradigm for the study of physical forces in the bacterial world. Cycles of elongations and retractions of Type IV pili enables N. gonorrhoeaebacteria to exert forces on its environment, forces that play major roles in the life cycle of this pathogen. In order to better understand the role of these forces, there is a need to fully characterize them. Here, we present two different techniqu ...201221993648
Comparison of in vivo bioluminescence imaging and lavage biomarkers to assess pulmonary inflammation.Gram-negative bacterial endotoxin triggers innate immunity via TLR-4 and NF-kB signal activation. The aim of this study was to evaluate the use of transgenic mice expressing luciferase as a marker of NF-kB activation for exploring innate immune responses to pulmonary endotoxin exposure over time thus obviating the need for serial necropsies. Transgenic rNF-kB-Luc BALB/c mice were exposed to two different types of endotoxin (Neisseria meningitidis lipooligosaccharide, and Escherichia coli lipopol ...201222133556
Analysis of parameters associated with prevention of cellular apoptosis by pathogenic neisseriae and purified porins.The process of cellular apoptosis is mediated by a number of microbial pathogens to modulate host defense mechanisms. Inhibition of apoptosis is thought to favor microbial survival, replication or immune evasion, while induction of apoptosis is likely to promote escape of the organisms from host cells. Several studies have reported that infection with Neisseria spp. can inhibit or reduce apoptotic cell death, thus allowing adaptation, intracellular replication, and immune evasion, events that ar ...201221993654
Protective role of Toll-like receptor 4 in experimental gonococcal infection of female mice.Neisseria gonorrhoeae is a common bacterial sexually transmitted infection. Like all Gram-negative bacteria, the outer membrane of the gonococcus is rich in endotoxin, a known ligand for Toll-like receptor (TLR)4. However, the role of endotoxin and that of its cognate receptor TLR4 in the mucosal response to acute gonococcal infection in the genital tract of women is unclear. To test this, we examined the course of infection after vaginal inoculation of N. gonorrhoeae in mice carrying the Lps(d) ...201221937985
Prevalence and Correlates of Mycoplasma genitalium Infection Among Female Sex Workers in Kampala, Uganda.Background. The importance of Mycoplasma genitalium in human immunodeficiency virus (HIV)-burdened sub-Saharan Africa is relatively unknown. We assessed the prevalence and explored determinants of this emerging sexually transmitted infection (STI) in high-risk women in Uganda. Methods. Endocervical swabs from 1025 female sex workers in Kampala were tested for Mycoplasma genitalium using a commercial Real-TM polymerase chain reaction assay. Factors associated with prevalent Mycoplasma genitalium, ...201222102734
methods for studying neisseria meningitidis biofilms.neisseria meningitidisis an organism whose environmental niche is limited to the human host. it can frequently colonize the human nasopharynx and has the ability to cause severe systemic infections. these infections can be sporadic, endemic or occur in outbreaks associated with more virulent meningococcal strains. studies have demonstrated that the meningococcus can form biofilms both in vivo and ex vivo. in this chapter, we discuss methods to establish biofilms in the laboratory for in-depth bi ...201221993646
evaluation of screening tests for detecting chlamydia trachomatis: bias associated with the patient-infected-status algorithm.in recent years, the evaluation of nucleic acid amplification tests (naats) for detecting chlamydia trachomatis and neisseria gonorrhea is based on a methodology called the patient-infected-status algorithm (pisa). in the simplest version of pisa, 4 test-specimen combinations (comparator tests) are used to define the gold standard. if a person shows a positive result by any 2 or more of these 4 comparator tests, the person is classified as infected; otherwise, the person is considered to be unin ...201222157304
ongoing sexually transmitted disease acquisition and risk-taking behavior among us hiv-infected patients in primary care: implications for prevention interventions.to better understand the factors associated with hiv- and sexually transmitted disease (std)-transmitting behavior among hiv-infected persons, we estimated std prevalence and incidence and associated risk factors among a diverse sample of hiv-infected patients in primary care.201222183836
tmt labelling for the quantitative analysis of adaptive responses in the meningococcal proteome.in addition to standard gel-based proteomic approaches, gel-free approaches using isobaric label reagents, such as tandem mass tags (tmt), provide a straightforward method for studying adaptations in microbial proteomes to changing environmental conditions. this approach does not have the known difficulties of 2-d gel electrophoresis with proteins of extreme biochemical properties. the workflow described here was designed to study adaptive responses in bacteria and has been applied to study the ...201221993643
recalibrating the gram stain diagnosis of male urethritis in the era of nucleic acid amplification testing.criteria for diagnosis of male urethritis based on a gram-stained smear (gss) of urethral discharge were developed before the era of nucleic acid amplification testing (naat) for neisseria gonorrhoeae (ng) and chlamydia trachomatis (ct) and may be too stringent when considering the higher sensitivity of naat.201222183839
identification and functional characterization of srnas in neisseria meningitidis.a riboregulated network, in which small rnas (srnas) regulate the stability and thus translation of transcripts (mrna), has only recently been discovered in prokaryotes. yet, during the last 5 years, hundreds of srnas have been identified in various bacterial species by using a wide variety of both computational and experimental approaches. the majority of the srnas interact with the 5'-untranslated region (utr) of target mrnas, thereby influencing the stability of target mrnas, or by either sup ...201221993640
Transcriptome analyses in the interaction of Neisseria meningitidis with mammalian host cells.Infectious disease research has been revolutionized by two recent developments in the field of genome biology: (1) the sequencing of the human genome as well as many pathogen genomes and (2) the development of high-throughput technologies including microarray technology, proteomics, and metabolomics. Microarray studies enable a deeper understanding of the genetic evolution of pathogens and investigation of the determinants of pathogenicity on a whole-genome scale. Host studies, in turn, allow fo ...201221993652
clinical evaluation of the bd probetec™ neisseria gonorrhoeae qx amplified dna assay on the bd viper™ system with xtr™ technology.background:: the excellent sensitivity and specificity of commercially available nucleic acid amplification tests (naats) for the identification of neisseria gonorrhoeae have been demonstrated. this study evaluated the performance of the bd probetec™ n. gonorrhoeae q (gcq) amplified dna assay on the bd viper™ system with xtr™ technology in a multicenter study. methods:: specimens were collected at 7 geographically diverse clinical sites from 1846 women and men attending sexually transmitted dise ...201222249304
transactional sexual relationships, sexually transmitted infection risk, and condom use among young black women in peri-urban areas of the western cape province of south africa.background: transactional sexual behavior has been demonstrated as an important factor underlying the hiv epidemic in sub-saharan africa. the aim of this study was to evaluate the relationship between having a history of transactional sexual relationships with condom use and sti risk. methods: participants completed a behavioral questionnaire in isixhosa and provided self-collected vaginal swabs which were tested for chlamydia trachomatis, neisseria gonorrhea, and trichomonas vaginalis. multinom ...201222265179
first cases of neisseria gonorrhoeae resistant to ceftriaxone in catalonia, spain, may 2011. 201222244992
meningococcal outer membrane protein nhha triggers apoptosis in macrophages.phagocytotic cells play a fundamental role in the defense against bacterial pathogens. one mechanism whereby bacteria evade phagocytosis is to produce factors that trigger apoptosis. here we identify for the first time a meningococcal protein capable of inducing macrophage apoptosis. the conserved meningococcal outer membrane protein nhha (neisseria hia/hsf homologue a, also known as hsf) mediates bacterial adhesion and interacts with extracellular matrix components heparan sulphate and laminin. ...201222238624
mper regulates the mtr efflux locus in neisseria gonorrhoeae and modulates antimicrobial resistance by an iron-responsive mechanism.previous studies have shown that the mper transcriptional regulator produced by neisseria gonorrhoeae represses expression of mtrf, which encodes a putative inner membrane protein (mtrf). mtrf works as an accessory protein with the mtr efflux pump helping gonococci to resist high levels of diverse hydrophobic antimicrobials. regulation of mper has been reported to occur by an iron-dependent mechanism involving fur (ferric uptake regulator). collectively, these observations suggest the presence o ...201222214775
comparison of three assays for the detection of chlamydia trachomatis and neisseria gonorrhoeae in surepath pap samples and the role of pre and post-cytology testing.chlamydia trachomatis (ct) and neisseria gonorrhoeae (ng) are common sexually transmitted infections and, there is interest in screening surepath liquid-based pap (l-pap) samples with aptima combo 2 (ac2), amplicor (amp) and probetec et (pt) assays. surepath l-pap samples and a cervical swab (cs) were collected from 394 women attending health clinics in hamilton and toronto, on. l-pap samples were tested in the three assays prior to processing for cytology and the cs sample was tested by ac2. th ...201222259215
new statistical technique for analyzing mic-based susceptibility data.seventeen laboratories participated in a cooperative study to validate the regional susceptibility testing of neisseria gonorrhoeae in the netherlands. international reference strains were distributed. each laboratory determined the mic of ciprofloxacin, penicillin and tetracycline, for each strain by e-test. to explore a more transparent assessment of quality and comparability, a statistical regression model was fitted to the data that accounted for the censoring of the mics. the mean mic as fo ...201222232288
epidemiology of sexually transmitted infections, hiv, and related high-risk behaviors among female sex workers in guangxi autonomous region, china.this study assessed the epidemiology of sexually transmitted infections (stis), hiv, and associated risk factors among female sex workers (fsws) in guangxi autonomous region, china. a cross-sectional study of 488 fsws was conducted using a structured questionnaire to collect sociodemographic and behavioral information. biological specimens from subjects were sampled to detect various stis and hiv infection. among fsws, the prevalence rates of syphilis, neisseria gonorrhoeae, chlamydia trach ...201222274163
inhibition of bacterial carbonic anhydrases and zinc proteases: from orphantargets to innovative new antibiotic drugs.zinc-containing enzymes, such as carbonic anhydrases (cas) and metalloproteases (mps) play critical functions in bacteria, being involved in various steps of their life cycle, which are important for survival, colonization, acquisition of nutrients for growth and proliferation, facilitation of dissemination, invasion and pathogenicity. the development of resistance to many classes of clinically used antibiotics emphasizes the need of new antibacterial drug targets to be explored. there is a weal ...201222214451
Cost Savings and Increased Efficiency Using a Stratified Specimen Pooling Strategy for Chlamydia trachomatis and Neisseria gonorrhoeae.Idaho Chlamydia trachomatis-Neisseria gonorrhoeae specimens from July 2009 were pooled by stratified specimen pooling, an approach that removes high-risk specimens from the pooling population and pools low-risk specimens to maximize pooling efficiency. This approach reduced pool positivity rates by 8%, repeated tests by 9%, and saved 47.4% in direct costs.201222183846
Two Strikingly Different Signaling Pathways Are Induced by Meningococcal Type IV Pili on Endothelial and Epithelial Cells.Following adhesion on brain microvasculature, Neisseria meningitidis is able to cross the blood-brain barrier (BBB) by recruiting the polarity complex and the cell junction proteins, thus allowing the opening of the paracellular route. This feature is the consequence of the activation by the type IV pili of the ß(2)-adrenergic receptor/ß-arrestin signaling pathway. Here, we have extended this observation to primary peripheral endothelial cells, and we report that the interaction of N. meningitid ...201222064711
Reply to "Routine Confirmation of Positive Nucleic Acid Amplification Test Results for Neisseria gonorrhoeae Is Not Necessary". 201222203752
access to health services and sexually transmitted infections in a cohort of relocating african american public housing residents: an association between travel time and infection.background:: high incidence and prevalence of sexually transmitted infection (sti) in blacks have been attributed to multiple factors. however, few articles have discussed spatial access to healthcare as a driver of disparities. the objective of this analysis was to evaluate the relationship between travel time to a healthcare provider and the likelihood of testing positive for 1 of 3 stis in a sample of adults living in public housing. methods:: one hundred and eight black adults in atlanta, ga ...201222249300
Meningococcal ligands and molecular targets of the host.Meningococcal mechanisms of adhesion are complex, involving multiple adhesins and their respective target receptors on host cells. Three major surface structures--pili, Opa, and Opc--have been known for some time to mediate meningococcal adhesion to target human cells. More recently, several other relatively minor adhesins have also come to light. The literature on bacterial adhesion mechanisms provides numerous examples of various adhesins acting cooperatively in an apparently hierarchical and ...201221993644
adenylylation control by intra- or intermolecular active-site obstruction in fic proteins.fic proteins that are defined by the ubiquitous fic (filamentation induced by cyclic amp) domain are known to catalyse adenylylation (also called ampylation); that is, the transfer of amp onto a target protein. in mammalian cells, adenylylation of small gtpases through fic proteins injected by pathogenic bacteria can cause collapse of the actin cytoskeleton and cell death. it is unknown how this potentially deleterious adenylylation activity is regulated in the widespread fic proteins that are f ...201222266942
human dendritic cell culture and bacterial infection.dendritic cells (dc) play a key role in the development of natural immunity to microbes. the dc form a bridge between the innate and adaptive immune system by providing key instructions particularly to antigen naïve t-cells. the interaction of dc with t lymphocytes involves three signals: (1) antigen processing and presentation in context of mhc class i and/or ii, (2) expression of t cell co-stimulatory molecules, and (3) cytokine production. studying the interactions of dcs with specific pathog ...201221993649
Microbiota in the oral subgingival biofilm is associated with obesity in adolescence.To test the hypothesis whether microbiota in oral biofilm is linked with obesity in adolescents we designed this cross-sectional study. Obese adolescents (n = 29) with a mean age of 14.7 years and normal weight subjects (n = 58) matched by age and gender were examined with respect to visible plaque index (VPI%) and gingival inflammation (bleeding on probing (BOP%)). Stimulated saliva was collected. They answered a questionnaire concerning medical history, medication, oral hygiene habits, smoking ...201221996660
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