Publications

TitleAbstractYear(sorted ascending)
Filter
PMID
Filter
coevolution of activating and inhibitory receptors within mammalian carcinoembryonic antigen families.most rapidly evolving gene families are involved in immune responses and reproduction, two biological functions which have been assigned to the carcinoembryonic antigen (cea) gene family. to gain insights into evolutionary forces shaping the cea gene family we have analysed this gene family in 27 mammalian species including monotreme and marsupial lineages.201020132533
in vitro antibacterial activities of jnj-q2, a new broad-spectrum fluoroquinolone.jnj-q2, a novel fluorinated 4-quinolone, was evaluated for its antibacterial potency by broth and agar microdilution mic methods in studies focused on skin and respiratory tract pathogens, including strains exhibiting contemporary fluoroquinolone resistance phenotypes. against a set of 118 recent clinical isolates of streptococcus pneumoniae, including fluoroquinolone-resistant variants bearing multiple dna topoisomerase target mutations, an mic(90) value for jnj-q2 of 0.12 microg/ml was determi ...201020176911
virulence-associated trimeric autotransporters of haemophilus parasuis are antigenic proteins expressed in vivo.glässer's disease is a re-emerging swine disease characterized by a severe septicaemia. vaccination has been widely used to control the disease, although there is a lack of extended cross-protection. trimeric autotransporters, a family of surface exposed proteins implicated in host-pathogen interactions, are good vaccine candidates. members of this family have been described in haemophilus parasuis and designated as virulence-associated trimeric autotransporters (vtaa). in this work, we produced ...201019995512
capacity of serotype 19a and 15b/c streptococcus pneumoniae isolates for experimental otitis media: implications for the conjugate vaccine.non-vaccine streptococcus pneumoniae serotypes are increasingly associated with disease. we evaluated isolates of the same sequence type (st199) but different serotypes (15b/c, 19a) for growth in vitro, and pathogenic potential in a chinchilla otitis media model. we also developed a quantitative pcr (qpcr) assay to quantitatively assess each isolate, circumventing the need for selectable markers. in vitro studies showed faster growth of serotype 19a over 15b/c. both were equally capable of colon ...201020067753
vitronectin binds to the head region of moraxella catarrhalis ubiquitous surface protein a2 and confers complement-inhibitory activity.the serum resistance of the common respiratory pathogen moraxella catarrhalis is mainly dependent on ubiquitous surface proteins (usp) a1 and a2 that interact with complement factor 3 (c3) and complement inhibitor c4b binding protein (c4bp) preventing the alternative and classical pathways of the complement system respectively. uspa2 also has the capacity to attract vitronectin that in turn binds c9 and hereby inhibits membrane attack complex (mac) formation. we found uspa2 as a major vitronecti ...201020199596
rapid differentiation of francisella species and subspecies by fluorescent in situ hybridization targeting the 23s rrna.francisella (f.) tularensis is the causative agent of tularemia. due to its low infectious dose, ease of dissemination and high case fatality rate, f. tularensis was the subject in diverse biological weapons programs and is among the top six agents with high potential if misused in bioterrorism. microbiological diagnosis is cumbersome and time-consuming. methods for the direct detection of the pathogen (immunofluorescence, pcr) have been developed but are restricted to reference laboratories.201020205957
antimicrobial characterisation of cem-101 activity against respiratory tract pathogens, including multidrug-resistant pneumococcal serogroup 19a isolates.cem-101 is a novel fluorinated macrolide-ketolide with potent activity against bacterial pathogens that are susceptible or resistant to other macrolide-lincosamide-streptogramin b (mls(b))-ketolide agents. cem-101 is being developed for oral and parenteral use in moderate to moderately severe community-acquired bacterial pneumonia. the objective of this study was to assess the activity of cem-101 and comparators against contemporary respiratory tract infection (rti) isolates. a worldwide sample ...201020211548
a two-tube combined taqman/sybr green assay to identify mycobacteria and detect single global lineage-defining polymorphisms in mycobacterium tuberculosis.we have developed a novel real-time pcr assay to identify and perform preliminary genotyping of mycobacteria in a manner tailored to our local service. within a single thermocycler run, mycobacterial 16s rdna and the mycobacterium tuberculosis global lineage-defining rd750 polymorphism are targeted in separate reaction tubes, each of which includes both taqman and sybr green chemistries. the results of this 16s-rd assay differentiate m. tuberculosis complex (mtbc) from nontuberculous mycobacteri ...201020093392
early biofilm formation on microtiter plates is not correlated with the invasive disease potential of streptococcus pneumoniae.biofilm formation has been suggested to play an important role during streptococcus pneumoniae nasopharyngeal colonization and may facilitate progression to pneumonia. to test whether the ability of s. pneumoniae to form biofilms was important for virulence we screened the ability of 30 invasive and 22 non-invasive clinical isolates of serotype 6a and 6b to form early biofilms on polystyrene microtiter plates and infect mice following intranasal and intratracheal challenge. we first determined t ...201020096771
current management of pediatric acute otitis media.acute otitis media (aom) is the most common childhood bacterial infection for which antibiotics are prescribed worldwide. the most common pathogens causing aom in children are streptococcus pneumoniae, nontypeable haemophilus influenzae, moraxella catarrhalis and group a streptococcus. antibiotic resistance is increasing among the bacterial pathogens causing aom, with percentages of penicillin- and macrolide-resistant s. pneumoniae strains estimated to be between 30 and 70%, and of beta-lactamas ...201020109045
nxl-103, a combination of flopristin and linopristin, for the potential treatment of bacterial infections including community-acquired pneumonia and mrsa.novexel is developing the novel, orally active, semisynthetic streptogramin nxl-103, which has potential therapeutic application in the treatment of community-acquired pneumonia, community- or hospital-acquired mrsa, vancomycin-resistant enterococcus, and acute bacterial skin and soft tissue infections. nxl-103 is a combination of streptogramin a:streptogramin b components, initially developed in a 70:30 dose ratio. in multiple in vitro studies, nxl-103 demonstrated potent activity against diffe ...201020112172
b cell activation by outer membrane vesicles--a novel virulence mechanism.secretion of outer membrane vesicles (omv) is an intriguing phenomenon of gram-negative bacteria and has been suggested to play a role as virulence factors. the respiratory pathogens moraxella catarrhalis reside in tonsils adjacent to b cells, and we have previously shown that m. catarrhalis induce a t cell independent b cell response by the immunoglobulin (ig) d-binding superantigen mid. here we demonstrate that moraxella are endocytosed and killed by human tonsillar b cells, whereas omv have t ...201020090836
community-acquired upper respiratory tract infections and the role of third-generation oral cephalosporins.common community-acquired infections include those of the upper respiratory tract. in the 1990s, the antimicrobial treatment of upper respiratory tract infections focused on penicillin-resistant streptococcus pneumoniae. however, following the introduction of a pneumococcal conjugate vaccine, a decrease in invasive pneumococcal disease occurred, and in the case of otitis media a shift towards haemophilus influenzae as the predominant causative pathogen was observed. future antimicrobial therapy ...201020014898
etiology of community-acquired pneumonia: increased microbiological yield with new diagnostic methods.the microbial etiology of community-acquired pneumonia (cap) is still not well characterized. during the past few years, polymerase chain reaction (pcr)-based methods have been developed for many pathogens causing respiratory tract infections. the aim of this study was to determine the etiology of cap among adults-especially the occurrence of mixed infections among patients with cap-by implementing a new diagnostic pcr platform combined with conventional methods.201020014950
a systemic neutrophil response precedes robust cd8(+) t-cell activation during natural respiratory syncytial virus infection in infants.severe primary respiratory syncytial virus (rsv) infections are characterized by bronchiolitis accompanied by wheezing. controversy exists as to whether infants suffer from virus-induced lung pathology or from excessive immune responses. furthermore, detailed knowledge about the development of primary t-cell responses to viral infections in infants is lacking. we studied the dynamics of innate neutrophil and adaptive t-cell responses in peripheral blood in relation to the viral load and paramete ...201020015982
a systemic neutrophil response precedes robust cd8(+) t-cell activation during natural respiratory syncytial virus infection in infants.severe primary respiratory syncytial virus (rsv) infections are characterized by bronchiolitis accompanied by wheezing. controversy exists as to whether infants suffer from virus-induced lung pathology or from excessive immune responses. furthermore, detailed knowledge about the development of primary t-cell responses to viral infections in infants is lacking. we studied the dynamics of innate neutrophil and adaptive t-cell responses in peripheral blood in relation to the viral load and paramete ...201020015982
development of a novel dna microarray to detect bacterial pathogens in patients with chronic obstructive pulmonary disease (copd).a novel microarray was constructed with dna pcr product probes targeting species specific functional genes of nine clinically significant respiratory pathogens, including the gram-positive organisms (streptococcus pneumoniae, streptococcus pyogenes), the gram-negative organisms (chlamydia pneumoniae, coxiella burnetii haemophilus spp., legionella pneumophila, moraxella catarrhalis, and pseudomonas aeruginosa), as well as the atypical bacterium, mycoplasma pneumoniae. in a "proof-of-concept" eval ...201020074591
disordered microbial communities in asthmatic airways.a rich microbial environment in infancy protects against asthma [1], [2] and infections precipitate asthma exacerbations [3]. we compared the airway microbiota at three levels in adult patients with asthma, the related condition of copd, and controls. we also studied bronchial lavage from asthmatic children and controls.201020052417
high-throughput identification of bacteria and yeast by matrix-assisted laser desorption ionization-time of flight mass spectrometry in conventional medical microbiology laboratories.matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) is suitable for high-throughput and rapid diagnostics at low costs and can be considered an alternative for conventional biochemical and molecular identification systems in a conventional microbiological laboratory. first, we evaluated maldi-tof ms using 327 clinical isolates previously cultured from patient materials and identified by conventional techniques (vitek-ii, api, and biochemical tests). discre ...201020053859
atypical bacteria in adenoids and tonsils of children requiring adenotonsillectomy.the results of this study suggest that atypical bacteria may be involved not only in acute upper airway diseases but also in recurrent infections requiring adenoidectomy and/or tonsillectomy. therefore, their identification, followed by an appropriate treatment, should be considered.201019958241
[the role of macrolides in treatment of exacerbations of chronic obstructive pulmonary disease].exacerbations of chronic obstructive pulmonary disease (copd) cause a lot of hospital admissions, mortality, and strongly influence health-related quality of life. approximately half of copd exacerbations are associated with bacterial infections and many patients have lower airways colonization. current guidelines recommend antibotic therapy in course of copd exacerbation for patients with sputum purulence and suggest correlation between severity of symptoms and the type of infecting pathogen. t ...201020491344
activity of a novel series of acylides active against community-acquired respiratory pathogens.resistance to macrolides and beta-lactams has increased sharply amongst key respiratory pathogens, leading to major concern. a novel series of acylides was designed to overcome this resistance and was evaluated for in vitro and in vivo activity. this series of acylides was designed starting from clarithromycin by changing the substitution on the desosamine nitrogen, followed by conversion to 3-o-acyl and 11,12-carbamate. minimum inhibitory concentrations (mics) of acylides were determined agains ...201020493666
simple sequence repeats and genome plasticity in streptococcus agalactiae.simple sequence repeats (ssrs) and their role in phase variation have been extensively studied in gram-negative organisms, where they have been associated with antigenic variation and other adaptation strategies. in this study, we apply comparative genomics in order to find evidence of slipped-strand mispairing in the human gram-positive pathogen streptococcus agalactiae. in two consecutive screenings, 2,233 (650 + 1,583) ssrs were identified in our reference genome 2603v/r, and these loci were ...201020494995
adenoidectomy and nasopharyngeal carriage of streptococcus pneumoniae in young children.the effect of adenoidectomy on nasopharyngeal colonisation of pathogens has not previously been evaluated. the authors studied the effect of adenoidectomy on nasopharyngeal colonisation by bacteria causing otitis media and the effect of adenoidectomy on the development of pneumococcal capsular polysaccharide antibodies.201020504840
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 ...201020504986
community-acquired bloodstream infections in africa: a systematic review and meta-analysis.data on the prevalence and causes of community-acquired bloodstream infections in africa are scarce. we searched three databases for studies that prospectively studied patients admitted to hospital with at least a blood culture, and found 22 eligible studies describing 58 296 patients, of whom 2051 (13.5%) of 15 166 adults and 3527 (8.2%) of 43 130 children had bloodstream infections. 1643 (29.1%) non-malaria bloodstream infections were due to salmonella enterica (58.4% of these non-typhoidal sa ...201020510282
the immunogenicity of the liposome-associated outer membrane proteins (omps) of moraxella catarrhalis.the outer membrane proteins (omps) are the most immunogenic and attractive of the moraxella catarrhalis vaccine antigens that may induce the protective immune response. the aim of this study was to determine the effectiveness of two types of omp-associated phosphatidylcholine (pc) liposomal formulations (omps-pc, pc-omps) and of zwittergent-based proteomicelles (omps-z) in potentiating an anti-omp systemic immune response in mice. the immunogenicities of the above preparations were evaluated by ...201019851720
human complement regulators c4b-binding protein and c1 esterase inhibitor interact with a novel outer surface protein of borrelia recurrentis.the spirochete borrelia recurrentis is the causal agent of louse-borne relapsing fever and is transmitted to humans by the infected body louse pediculus humanus. we have recently demonstrated that the b. recurrentis surface receptor, hcpa, specifically binds factor h, the regulator of the alternative pathway of complement activation, thereby inhibiting complement mediated bacteriolysis. here, we show that b. recurrentis spirochetes express another potential outer membrane lipoprotein, termed cih ...201020532227
vibrio cholerae el tor tcpa crystal structure and mechanism for pilus-mediated microcolony formation.type iv pili (t4p) are critical to virulence for vibrio cholerae and other bacterial pathogens. among their diverse functions, t4p mediate microcolony formation, which protects the bacteria from host defences and concentrates secreted toxins. the t4p of the two v. cholerae o1 disease biotypes, classical and el tor, share 81% identity in their tcpa subunits, yet these filaments differ in their interaction patterns as assessed by electron microscopy. to understand the molecular basis for pilus-med ...201020545841
large screening of ca-mrsa among staphylococcus aureus colonizing healthy young children living in two areas (urban and rural) of portugal.the incidence of pediatric infections due to community-associated methicillin-resistant staphylococcus aureus (ca-mrsa), including children with no identifiable risk factors, has increased worldwide in the last decade. this suggests that healthy children may constitute a reservoir of mrsa in the community. in this study, nested within a larger one on nasopharyngeal ecology, we aimed to: (i) evaluate the prevalence of mrsa colonizing young children in portugal; and (ii) compare results with those ...201020438633
genome analysis of moraxella catarrhalis strain rh4, a human respiratory tract pathogen.moraxella catarrhalis is an emerging human-restricted respiratory tract pathogen that is a common cause of childhood otitis media and exacerbations of chronic obstructive pulmonary disease in adults. here, we report the first completely assembled and annotated genome sequence of an isolate of m. catarrhalis, strain rh4, which originally was isolated from blood of an infected patient. the rh4 genome consists of 1,863,286 nucleotides that form 1,886 protein-encoding genes. comparison of the rh4 ge ...201020453089
the development of a 16s rrna gene based pcr for the identification of streptococcus pneumoniae and comparison with four other species specific pcr assays.streptococcus pneumoniae is one of the most frequently encountered pathogens in humans but its differentiation from closely related but less pathogenic streptococci remains a challenge.201020426878
determinants of moraxella catarrhalis colonization in healthy dutch children during the first 14 months of life.moraxella catarrhalis is an established bacterial pathogen, previously thought to be an innocent commensal of the respiratory tract of children and adults. the objective of this study was to identify significant risk factors associated with m. catarrhalis colonization in the first year of life in healthy dutch children. this study investigated a target cohort group of 1079 children forming part of the generation r study, a population-based prospective cohort study following children from fetal l ...201019681950
biochemical analysis of lgt3, a glycosyltransferase of the bacterium moraxella catarrhalis.the lipooligosaccharide (los) of moraxella catarrhalis is unusual in that it lacks heptose. the sugar linking oligosaccharide to lipid a is a trisubstituted glucose. a single enzyme, lgt3, is suggested to trisubstitute this core sugar. the lgt3 gene encodes two distinct domains with high similarity to glucosyltransferases of the gt-a superfamily, thus encoding a bidomain, multifunctional glucosyltransferase. to characterise lgt3, the gene was amplified from m. catarrhalis, expressed in escherich ...201020153730
the interaction between respiratory viruses and pathogenic bacteria in the upper respiratory tract of asymptomatic aboriginal and non-aboriginal children.associations between respiratory viruses and the bacterial pathogens streptococcus pneumoniae, haemophilus influenzae, and moraxella catarrhalis may be important in the pathogenesis of otitis media (om). however, data on asymptomatic identification rates of respiratory viruses are limited, particularly in indigenous populations, who suffer a high burden of om.201020134359
performance of matrix-assisted laser desorption ionization-time of flight mass spectrometry for identification of bacterial strains routinely isolated in a clinical microbiology laboratory.matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) has recently been introduced in diagnostic microbiology laboratories for the identification of bacterial and yeast strains isolated from clinical samples. in the present study, we prospectively compared maldi-tof ms to the conventional phenotypic method for the identification of routine isolates. colonies were analyzed by maldi-tof ms either by direct deposition on the target plate or after a formic acid- ...201020220166
a new paradigm of bacteria-gut interplay brought through the study of shigella.bacteria-gut epithelial interplay and the mucosal immune response are the most critical issues in determining the fate of bacterial infection and the severity of diseases. shigella species (abbreviated here as shigella), the causative agent of bacillary dysentery (shigellosis), are highly adapted human pathogens that are capable of invading and colonizing the intestinal epithelium, which results in severe inflammatory colitis. shigella secrete a large and diverse number (more then 50) of effecto ...201020228623
comparative in vitro antimicrobial activities of torezolid (tr-700), the active moiety of a new oxazolidinone, torezolid phosphate (tr-701), determination of tentative disk diffusion interpretive criteria, and quality control ranges.this study assessed the spectrum of activity of torezolid (tr-700), the active moiety of torezolid phosphate (tr-701), and proposes tentative mic and disk diffusion breakpoints as well as quality control ranges. the in vitro susceptibilities of 1,096 bacterial isolates, representing 23 different species or phenotypic groups, were determined for torezolid, linezolid, cefotaxime, and levofloxacin using clinical and laboratory standards institute (clsi) broth microdilution mics, minimum bactericida ...201020231392
swab transport in amies gel followed by frozen storage in skim milk tryptone glucose glycerol broth (stggb) for studies of respiratory bacterial pathogens.nasopharyngeal carriage studies are needed to monitor changes in important bacterial pathogens in response to vaccination and antibiotics. commercial swab transport followed by transfer to skim milk tryptone glucose glycerol broth for frozen storage is an option for studies of streptococcus pneumoniae, haemophilus influenzae and moraxella catarrhalis.201020298727
duplex real-time reverse transcriptase pcr assays for rapid detection and identification of pandemic (h1n1) 2009 and seasonal influenza a/h1, a/h3, and b viruses.reports of a novel influenza virus type a (h1n1), now designated by the world health organization as pandemic (h1n1) 2009, emerged from the united states and mexico in april 2009. the management of the pandemic in australia required rapid and reliable testing of large numbers of specimens for the novel influenza strain and differentiation from seasonal influenza strains. a real-time reverse transcriptase pcr (rt-pcr) assay for the detection of pandemic (h1n1) 2009 was designed and used with exis ...201020071557
role of infection in the development and exacerbation of asthma.respiratory infections are associated with wheezing illnesses in all ages and may also impact the development and severity of asthma. respiratory tract infections caused by viruses, chlamydophila or mycoplasma have been hypothesized to have significant roles in the pathogenesis of asthma. progress is being made toward establishing the mechanisms by which these agents can cause acute wheezing and impact the pathophysiology of asthma. host factors probably contribute to the risk of asthma inceptio ...201020305826
single assay for simultaneous detection and differential identification of human and avian influenza virus types, subtypes, and emergent variants.for more than four decades the cause of most type a influenza virus infections of humans has been attributed to only two viral subtypes, a/h1n1 or a/h3n2. in contrast, avian and other vertebrate species are a reservoir of type a influenza virus genome diversity, hosting strains representing at least 120 of 144 combinations of 16 viral hemagglutinin and 9 viral neuraminidase subtypes. viral genome segment reassortments and mutations emerging within this reservoir may spawn new influenza virus str ...201020140251
time-kill assay results for a linalool-hinokitiol-based eyelid cleanser for lid hygiene.time-kill testing was performed for a linalool-hinokitiol-based eyelid cleanser against pseudomonas aeruginosa, moraxella catarrhalis, escherichia coli, serratia marcescens, staphylococcus aureus, methicillin-resistant s. aureus (mrsa), staphylococcus epidermidis, and pityrosporum ovale to evaluate its efficacy.201020308878
ceftaroline: a new cephalosporin with activity against resistant gram-positive pathogens.ceftaroline is a novel, broad-spectrum, advanced-generation cephalosporin whose action is mediated by binding to penicillin-binding proteins in bacteria, consistent with other beta-lactam antibiotics. ceftaroline is distinct in that it has antimicrobial activity against multidrug-resistant staphylococcus aureus (including methicillin-resistant s. aureus, vancomycin-intermediate s. aureus [visa], heteroresistant visa, and vancomycin-resistant s. aureus), streptococcus pneumonia (including drug-re ...201020334458
simultaneous assay for four bacterial species including alloiococcus otitidis using multiplex-pcr in children with culture negative acute otitis media.the 3 most commonly encountered bacteria in acute otitis media (aom) are streptococcus pneumoniae, haemophilus influenzae, and moraxella catarrhalis. conventional culture methods detect these pathogens in only 60% to 70% of cases of aom. alloiococcus otitidis, another potential pathogen, has often been ignored.201020335823
activity of the streptogramin antibiotic etamycin against methicillin-resistant staphylococcus aureus.the alarming rise of hospital- and community-associated methicillin-resistant staphylococcus aureus (ha- and ca-mrsa) infections has prompted a desperate search for novel antibiotics. we discovered the streptogramin etamycin produced by an actinomycete species isolated from the coast of fiji, the first time this antibiotic has been identified from a marine microbe. etamycin was extracted and purified from this strain (cns-575) and identified as a three-rotamer species by 2d nmr spectroscopy. eta ...201020339399
antimicrobial susceptibility of moraxella catarrhalis isolated from children in kalgoorlie-boulder, western australia.to investigate antimicrobial susceptibility of moraxella catarrhalis isolated from a cohort of children being followed in a study of the natural history of otitis media in a semi-arid region of western australia.201020350222
the diagnosis and treatment of elderly patients with acute exacerbation of chronic obstructive pulmonary disease and chronic bronchitis.the syndrome of chronic obstructive pulmonary disease (copd) consists of chronic bronchitis (cb), bronchiectasis, emphysema, and reversible airway disease that combine uniquely in an individual patient. older patients are at risk for copd and its components--emphysema, cb, and bronchiectasis. bacterial and viral infections play a role in acute exacerbations of copd (aecopd) and in acute exacerbations of cb (aecb) without features of copd. older patients are at risk for resistant bacterial organi ...201020398122
functional characterization of lcpa, a surface-exposed protein of leptospira spp. that binds the human complement regulator c4bp.we have previously shown that pathogenic leptospiral strains are able to bind c4b binding protein (c4bp). surface-bound c4bp retains its cofactor activity, indicating that acquisition of this complement regulator may contribute to leptospiral serum resistance. in the present study, the abilities of seven recombinant putative leptospiral outer membrane proteins to interact with c4bp were evaluated. the protein encoded by lic11947 interacted with this human complement regulator in a dose-dependent ...201020404075
ceacam1 recognition by bacterial pathogens is species-specific.carcinoembryonic antigen-related cell adhesion molecule 1 (ceacam1), an immunoglobulin (ig)-related glycoprotein, serves as cellular receptor for a variety of gram-negative bacterial pathogens associated with the human mucosa. in particular, neisseria gonorrhoeae, n. meningitidis, moraxella catarrhalis, and haemophilus influenzae possess well-characterized ceacam1-binding adhesins. ceacam1 is typically involved in cell-cell attachment, epithelial differentiation, neovascularisation and regulatio ...201020406467
innate signaling in otitis media: pathogenesis and recovery.otitis media (om) is the most prevalent childhood disease in developed countries. involvement of innate immunity mediated by toll-like receptors (tlrs) in om has been implicated primarily in cell lines and by association studies of innate immune gene polymorphisms with om prevalence. however, the precise role of innate immunity in om is incompletely understood. we review recent research that has advanced our understanding of how innate immunity in the middle ear is mediated by the interaction of ...201121049294
innate signaling in otitis media: pathogenesis and recovery.otitis media (om) is the most prevalent childhood disease in developed countries. involvement of innate immunity mediated by toll-like receptors (tlrs) in om has been implicated primarily in cell lines and by association studies of innate immune gene polymorphisms with om prevalence. however, the precise role of innate immunity in om is incompletely understood. we review recent research that has advanced our understanding of how innate immunity in the middle ear is mediated by the interaction of ...201121049294
vaccine preventable community-acquired pneumonia in hospitalized children in northwest china.community-acquired pneumonia (cap) is a major cause of morbidity in industrialized countries and morbidity/mortality in developing countries. in china, comprehensive studies of the etiology of cap in children aged between 2 months and 14 years who are serious enough to require hospitalization are lacking. previous studies have been limited in child age range, focused on fatal cases, and/or limited in etiologies sought. an understanding of the etiologies is needed for development of best preventi ...201120625346
association between nasopharyngeal load of streptococcus pneumoniae, viral coinfection, and radiologically confirmed pneumonia in vietnamese children.the interplay between nasopharyngeal bacterial carriage, viral coinfection, and lower respiratory tract infections (lrtis) is poorly understood. we explored this association in vietnamese children aged less than 5 years.201120686433
characterization of a moraxella species that causes epistaxis in macaques.bacteria of the genus moraxella have been isolated from a variety of mammalian hosts. in a prior survey of bacteria that colonize the rhesus macaque nasopharynx, performed at the tulane national primate research center, organisms of the moraxella genus were isolated from animals with epistaxis, or "bloody nose syndrome." they were biochemically identified as moraxella catarrhalis, and cryopreserved. another isolate was obtained from an epistatic cynomolgus macaque at the u.s. army medical resear ...201120667430
risk factors for otitis media in children with special emphasis on the role of colonization with bacterial airway pathogens: the generation r study.acute otitis media is the most frequent diagnosis in children visiting physicians' offices. risk factors for otitis media have been widely studied. yet, the correlation between bacterial carriage and the development of otitis media is not entirely clear. our aim was to study in a population-based prospective cohort the risk factors for otitis media in the second year of life with special emphasis on the role of colonization with streptococcus pneumoniae, haemophilus influenzae and moraxella cata ...201120821039
in vitro and in vivo profiles of ach-702, an isothiazoloquinolone, against bacterial pathogens.ach-702, a novel isothiazoloquinolone (itq), was assessed for antibacterial activity against a panel of gram-positive and gram-negative clinical isolates and found to possess broad-spectrum activity, especially against antibiotic-resistant gram-positive strains, including methicillin-resistant staphylococcus aureus (mrsa). for gram-negative bacteria, ach-702 showed exceptional potency against haemophilus influenzae, moraxella catarrhalis, and a neisseria sp. but was less active against members o ...201121464250
clinical impact of combined viral and bacterial infection in patients with community-acquired pneumonia.new methods for identifying respiratory pathogens have led to several reports of a high yield of mixed infections in patients with community-acquired pneumonia (cap). the clinical impact of these findings has, however, not been fully evaluated. we aimed to compare patients with a pure bacterial etiology with those with findings of both bacteria and virus regarding severity of illness and length of hospital stay.201121466255
airway microbiology and host defences in paediatric non-cf bronchiectasis.bronchiectasis in children without cystic fibrosis is most common in socioeconomically disadvantaged communities. recurrent pneumonia in early childhood and defective pulmonary defences are important risk factors. these help establish a 'vicious cycle' of impaired mucociliary clearance, infection, airway inflammation and progressive lung injury. haemophilus influenzae, streptococcus pneumoniae, moraxella catarrhalis and pseudomonas aeruginosa are the main infecting pathogens. h. influenzae predo ...201121458739
rna-oligonucleotide quantification technique (roqt) for the enumeration of uncultivated bacterial species in subgingival biofilms.approximately 35% of the species present in subgingival biofilms are as yet uncultivated, so their role in periodontal pathogenesis is unknown. the aim of the present study was to develop a high throughput method to quantify a wide range of cultivated and uncultivated taxa in subgingival biofilm samples associated with periodontal disease or health. oligonucleotides targeting the 16s ribosomal dna gene were designed, synthesized and labeled with digoxigenin. these probes were hybridized with the ...201121375703
in vitro activity of ceftaroline against gram-positive and gram-negative pathogens isolated from patients in canadian hospitals in 2009.the in vitro activities of ceftaroline and comparative agents were determined for a collection of the most frequently isolated bacterial pathogens from hospital-associated patients across canada in 2009 as part of the ongoing canward surveillance study. in total, 4,546 isolates from 15 sentinel canadian hospital laboratories were tested using the clinical and laboratory standards institute (clsi) broth microdilution method. compared with other cephalosporins, including ceftobiprole, cefepime, an ...201121402844
severe pneumococcal pneumonia: impact of new quinolones on prognosis.most guidelines have been proposing, for more than 15 years, a ß-lactam combined with either a quinolone or a macrolide as empirical, first-line therapy of severe community acquired pneumonia (cap) requiring icu admission. our goal was to evaluate the outcome of patients with severe cap, focusing on the impact of new rather than old fluoroquinolones combined with ß-lactam in the empirical antimicrobial treatments.201121406091
nationwide surveillance of bacterial respiratory pathogens conducted by the japanese society of chemotherapy in 2008: general view of the pathogens' antibacterial susceptibility.for the purpose of nationwide surveillance of the antimicrobial susceptibility of bacterial respiratory pathogens collected from patients in japan, the japanese society of chemotherapy conducted a third year of nationwide surveillance during the period from january to april 2008. a total of 1,097 strains were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections. susceptibility testing was evaluable with 987 strains (189 staphylococcus au ...201121409533
ceftaroline: a comprehensive update.ceftaroline is a novel broad-spectrum cephalosporin antibiotic currently under us food and drug administration (fda) review for a new drug application (nda), filed by cerexa, inc. (a wholly owned subsidiary of forest laboratories), for the treatment of complicated skin and skin-structure infections (csssis) and community-associated pneumonia (cap). the antibiotic acts by binding to penicillin-binding proteins in bacteria, consistent with other ß-lactams. the antimicrobial spectrum of ceftaroline ...201121420284
microbiology of sinusitis.most sinus infections are viral, and only a small proportion develops a secondary bacterial infection. rhinoviruses, influenza viruses, and parainfluenza viruses are the most common causes of sinusitis. the most common bacteria isolated from pediatric and adult patients with community-acquired acute purulent sinusitis are streptococcus pneumoniae, haemophilus influenzae, moraxella catarrhalis, and streptococcus pyogenes. staphylococcus aureus and anaerobic bacteria (prevotella and porphyromonas, ...201121364226
clinical and microbiological evaluation of hemodialysis-associated pneumonia (hdap): should hdap be included in healthcare-associated pneumonia?although hemodialysis-associated pneumonia (hdap) was included among the healthcare-associated pneumonias (hcap) in the 2005 american thoracic society (ats)/infectious diseases society of america (idsa) guideline, little information relevant to clinical epidemiology, especially microbiological characteristics, is available. this study aimed to reveal microbiological characteristics and clinical outcomes of hdap and to assess whether hdap should be included in the hcap category. we retrospectivel ...201121369775
detection of microorganisms in exhaled breath condensate during acute exacerbations of copd.summary at a glance: exhaled breath condensate (ebc) is a noninvasive method to assess airway biology. the aim of the present study was to evaluate ebc for the detection of microbial nucleic acids during acute exacerbations of copd (aecopd). bacterial nucleic acids can be identified in ebcs of copd patients with exacerbations, however, the results differed significantly from those of sputum. abstract: background and objective:  one hallmark of chronic obstructive pulmonary disease (copd) is colo ...201121470340
neisseria meningitidis adhesin nada targets {beta}1 integrins: functional similarity to yersinia invasin.meningococci are facultative-pathogenic bacteria endowed with a set of adhesins allowing colonization of the human upper respiratory tract, leading to fulminant meningitis and septicemia. the neisseria adhesin nada was identified in about 50% of n. meningitidis isolates and is closely related to the yersinia adhesin yada, the prototype of the oligomeric coiled-coil adhesin (oca) family. nada is known to be involved in cell adhesion, invasion, and induction of proinflammatory cytokines. because o ...201121471204
sore throat.about 10% of people present to primary healthcare services with sore throat each year. the causative organisms of sore throat may be bacteria (most commonly streptococcus) or viruses (typically rhinovirus), although it is difficult to distinguish bacterial from viral infections clinically. methods and outcomes: we conducted a systematic review and aimed to answer the following clinical questions: what are the effects of interventions to reduce symptoms of acute infective sore throat? what are th ...201121477389
ceftaroline fosamil: a new broad-spectrum cephalosporin.ceftaroline fosamil, the prodrug of the active metabolite, ceftaroline, is a new, broad-spectrum cephalosporin recently approved in the usa for the treatment of acute bacterial skin and skin structure infections (absssis) and community-acquired bacterial pneumonia (cabp). ceftaroline has potent in vitro activity against gram-positive organisms, including methicillin-resistant staphylococcus aureus and streptococcus pneumoniae, as well as common gram-negative organisms. the high affinity of cefta ...201121482565
changing needs of community-acquired pneumonia.community-acquired pneumonia (cap) is a serious condition associated with significant morbidity and potential long-term mortality. although the majority of patients with cap are treated as outpatients, the greatest proportion of pneumonia-related mortality and healthcare expenditure occurs among the patients who are hospitalized. there has been considerable interest in determining risk factors and severity criteria assessments to assist with site-of-care decisions. for both inpatients and outpat ...201121482567
comparative ceftaroline activity tested against pathogens associated with community-acquired pneumonia: results from an international surveillance study.to document the spectrum of activity of ceftaroline, the active form of the prodrug, ceftaroline fosamil, a new cephalosporin with anti-methicillin-resistant staphylococcal activity, against a surveillance collection of clinical isolates obtained from the usa and europe during 2008-09.201121482572
microbiology of animal bite wound infections.the microbiology of animal bite wound infections in humans is often polymicrobial, with a broad mixture of aerobic and anaerobic microorganisms. bacteria recovered from infected bite wounds are most often reflective of the oral flora of the biting animal, which can also be influenced by the microbiome of their ingested prey and other foods. bacteria may also originate from the victim's own skin or the physical environment at the time of injury. our review has focused on bite wound infections in ...201121482724
a conserved interaction between transferrin and transferrin-binding proteins from porcine pathogens.gram-negative porcine pathogens from the pasteurellaceae family possess a surface receptor complex capable of acquiring iron from porcine transferrin (ptf). this receptor consists of transferrin binding protein a (tbpa), a transmembrane iron transporter, and tbpb, a surface-exposed lipoprotein. questions remain as to how the receptor complex engages ptf in such a way that iron is positioned for release, and whether divergent strains present distinct recognition sites on tf. in this study, the tb ...201121487007
adhesion and host cell modulation: critical pathogenicity determinants of bartonella henselae.abstract: bartonella henselae, the agent of cat scratch disease and the vasculoproliferative disorders bacillary angiomatosis and peliosis hepatis, contains to date two groups of described pathogenicity factors: adhesins and type iv secretion systems. bartonella adhesin a (bada), the trw system and possibly filamentous hemagglutinin act as promiscous or specific adhesins, whereas the virulence locus (vir)b/vird4 type iv secretion system modulates a variety of host cell functions. bada mediates b ...201121489243
bacteriological findings and antimicrobial resistance in odontogenic and non-odontogenic chronic maxillary sinusitis.the main objectives of this study were to estimate the frequency of chronic maxillary sinusitis of dental origin, and to evaluate the microbiology of odontogenic and non-odontogenic chronic maxillary sinusitis. aspirates of 59 patients with chronic maxillary sinusitis (47 non-odontogenic, 12 odontogenic), collected during a 3-year period, were microbiologically processed for aerobic and anaerobic bacteria. moreover, in the isolated bacteria the antimicrobial susceptibility was evaluated. in this ...201121498651
risk factors for serotype 19a carriage after introduction of 7-valent pneumococcal vaccination.abstract:201121501471
sitafloxacin: in bacterial infections.sitafloxacin is a fluoroquinolone antibacterial with in vitro activity against a broad range of gram-positive and -negative bacteria, including anaerobic bacteria, as well as against atypical pathogens. it is approved in japan for use in a number of bacterial infections caused by sitafloxacin-susceptible strains of staphylococcus spp., streptococcus pneumoniae, other streptococcus spp., enterococcus spp., moraxella catarrhalis, escherichia coli, citrobacter spp., klebsiella spp., enterobacter sp ...201121504249
comparative study of immune status to infectious agents in elderly patients with multiple myeloma, waldenstrom's macroglobulinemia, and monoclonal gammopathy of undetermined significance.whereas patients with multiple myeloma (mm) have a well-documented susceptibility to infections, this has been less studied in other b-cell disorders, such as waldenstrom's macroglobulinemia (wm) and monoclonal gammopathy of undetermined significance (mgus). we investigated the humoral immunity to 24 different pathogens in elderly patients with mm (n = 25), wm (n = 16), and mgus (n = 18) and in age-matched controls (n = 20). antibody titers against pneumococci, staphylococcal alpha-toxin, tetanu ...201121508164
splunc1 promotes lung innate defense against mycoplasma pneumoniae infection in mice.short palate, lung, and nasal epithelium clone 1 (splunc1) protein is highly expressed in normal airways, but is dramatically decreased in allergic and cigarette smoke exposure settings. we have previously demonstrated splunc1 in vitro antibacterial property against mycoplasma pneumoniae (mp). however, its in vivo biological functions remain unclear. the objectives of this study were to determine the in vivo functions of splunc1 following bacterial (eg, mp) infection, and to examine the underlyi ...201121514430
pathogen yield and antimicrobial resistance patterns of chronic rhinosinusitis patients presenting to a tertiary rhinology centre.to examine the yield and resistance profile of pathogens in chronic rhinosinusitis (crs) patients receiving culture-directed management and to pay particular attention to the prevalence of methicillin-resistant staphylococcus aureus (mrsa) in this population.201121518646
antimicrobial resistance in urinary tract pathogens in canada from 2007 to 2009: canward surveillance study.from january 2007 to december 2009 an annual canadian national surveillance study (canward) tested 2943 urinary culture pathogens for antimicrobial susceptibilities following clinical and laboratory standards institute (clsi) guidelines. the most frequently isolated urinary pathogens (n, % of all isolates) were escherichia coli (1581, 54%), enterococci (410, 14%), klebsiella pneumoniae (274, 9%), proteus mirabilis (122, 4%), pseudomonas aeruginosa (100, 3%), and staphylococcus aureus (80, 3%). r ...201121537027
characterization of a cryptic plasmid psm429 and its application for heterologous expression in psychrophilic pseudoalteromonas.abstract: background: pseudoalteromonas is an important genus widespread in marine environment, and a lot of psychrophilic pseudoalteromonas strains thrive in deep sea and polar sea. by now, there are only a few genetic systems for pseudoalteromonas reported and no commercial pseudoalteromonas genetic system is available, which impedes the study of pseudoalteromonas, especially for psychrophilic strains. the aim of this study is to develop a heterologous expression system for psychrophilic pseud ...201121542941
the rna chaperone hfq is important for growth and stress tolerance in francisella novicida.the rna-binding protein hfq is recognized as an important regulatory factor in a variety of cellular processes, including stress resistance and pathogenesis. hfq has been shown in several bacteria to interact with small regulatory rnas and act as a post-transcriptional regulator of mrna stability and translation. here we examined the impact of hfq on growth, stress tolerance, and gene expression in the intracellular pathogen francisella novicida. we present evidence of hfq involvement in the abi ...201121573133
helicobacter pylori alpa and alpb bind host laminin and influence gastric inflammation in gerbils.helicobacter pylori persistently colonizes humans, causing gastritis, ulcers, and gastric cancer. adherence to the gastric epithelium has been shown to enhance inflammation, yet only a few h. pylori adhesins have been paired with targets in host tissue. the alpab locus has been reported to encode adhesins involved in adherence to human gastric tissue. we report that abrogation of h. pylori alpa and alpb reduces binding of h. pylori to laminin, while expression of plasmid-borne alpa confers lamin ...201121576328
moraxella catarrhalis outer membrane vesicles carry beta-lactamase and promote survival of streptococcus pneumoniae and haemophilus influenzae by inactivating amoxicillin.moraxella catarrhalis is a common pathogen found in children with upper respiratory tract infections, and in patients with chronic obstructive pulmonary disease during exacerbations. the bacterial species is often isolated together with streptococcus pneumoniae and haemophilus influenzae. outer membrane vesicles (omv) are released by m. catarrhalis and contain phospholipids, adhesins, and immunomodulatory compounds such as lipooligosaccharide. we have recently shown that m. catarrhalis omv exist ...201121576428
microbiology of bronchoalveolar lavage fluid in children with acute nonresponding or recurrent community-acquired pneumonia: identification of nontypeable haemophilus influenzae as a major pathogen.background. precise etiologic diagnosis in pediatric community-acquired pneumonia (cap) remains challenging. methods. we conducted a retrospective study of cap etiology in 2 groups of pediatric patients who underwent flexible bronchoscopy (fob) with bronchoalveolar lavage (bal); children with acute nonresponsive cap (nr-cap; n = 127) or recurrent cap (rec-cap; n = 123). procedural measures were taken to limit contamination risk and quantitative bacterial culture of bal fluid (significance cutoff ...201121628484
the autotransporter protein from bordetella avium, baa1, is involved in host cell attachment.bordetella avium is a gram negative upper respiratory tract pathogen of birds. b. avium infection of commercially raised turkeys is an agriculturally significant problem. here we describe the functional analysis of the first characterized b. avium autotransporter protein, baa1. autotransporters comprise a large family of proteins found in all groups of gram negative bacteria. although not unique to pathogenic bacteria, autotransporters have been shown to perform a variety of functions implicated ...201121632225
the utility of matrix assisted laser desorption/ionization time-of-flight mass spectrometry (maldi-tof ms) following introduction for routine laboratory bacterial identification.maldi-tof ms was evaluated prospectively in a diagnostic laboratory. 927 organisms were tested in triplicate; 2351/2781 (85%) species and 2681/2781 (96%) genus identifications were correct. known issues such as the misidentification of α-haemolytic streptococci as streptococcus pneumonia were easily corrected. identifications cost $aud0.45 per isolate and were available in minutes. maldi-tof ms is rapid, accurate and inexpensive.201121632894
viral-bacterial co-infection in australian indigenous children with acute otitis media.abstract: background: acute otitis media with perforation (aomwip) affects 40% of remote indigenous children during the first 18 months of life. streptococcus pneumoniae, haemophilus influenzae and moraxella catarrhalis are the primary bacterial pathogens of otitis media and their loads predict clinical ear state. our hypothesis is that antecedent respiratory viral infection increases bacterial density and progression to perforation. methods: a total of 366 nasopharyngeal swabs from 114 indigeno ...201121649905
sole infection by human metapneumovirus among children with radiographically diagnosed community-acquired pneumonia in a tropical region.limited information is available on the role of human metapneumovirus (hmpv) as the unique pathogen among children hospitalized for community-acquired pneumonia (cap) in a tropical region.201121651739
[prevalence of serotypes of streptococcus pneumoniae and other agents that cause acute otitis media in children in latin america. a systematic review of the literature].acute otitis media (aom) is a common diagnosis in children. streptococcus pneumoniae remains the most prevalent agent worldwide, followed by haemophilus influenzae. however, the introduction of pneumococcal vaccines has changed the microbiology of aom.201121660385
cigarette smoke modulates pge(2) and host defence against moraxella catarrhalis infection in human airway epithelial cells.airway bacterial infections pose a significant challenge to the management of copd, a disease mainly caused by cigarette smoking. however, the mechanisms of impaired airway mucosal innate immunity against bacteria in copd remain unclear. we examined the effect of cigarette smoke on prostaglandin e(2) (pge(2)) and downstream epithelial host defence mechanisms including the antimicrobial substance human β-defensin-2 (hbd-2).201121199162
a simple assay for 3-deoxy-d-manno-octulosonate cytidylyltransferase and its use as a pathway screen.this article describes the adaptation of a simple colorimetric assay for inorganic pyrophosphate to the enzyme 3-deoxy-d-manno-octulosonate cytidylyltransferase (cmp-kdo synthetase, kdsb, ec 2.7.7.38), a key enzyme in the biosynthesis of lipopolysaccharide (lps) in gram-negative organisms. this assay is particularly useful because it can be combined with the malachite green (mg) assay for inorganic phosphate to form an assay system capable of determining inorganic phosphate and inorganic pyropho ...201121669179
phenylbutyrate counteracts shigella mediated downregulation of cathelicidin in rabbit lung and intestinal epithelia: a potential therapeutic strategy.cathelicidins and defensins are endogenous antimicrobial peptides (amps) that are downregulated in the mucosal epithelia of the large intestine in shigellosis. oral treatment of shigella infected rabbits with sodium butyrate (nab) reduces clinical severity and counteracts the downregulation of cathelicidin (cap-18) in the large intestinal epithelia.201121673991
urine antibiotic activity in patients presenting to hospitals in laos: implications for worsening antibiotic resistance.abstract. widespread use of antibiotics may be important in the spread of antimicrobial resistance. we estimated the proportion of lao in- and outpatients who had taken antibiotics before medical consultation by detecting antibiotic activity in their urine added to lawns of bacillus stearothermophilus, escherichia coli, and streptococcus pyogenes. in the retrospective (n = 2,058) and prospective studies (n = 1,153), 49.7% (95% confidence interval [ci] = 47.4-52.0) and 36.2% (95% ci = 33.4-38.9), ...201121813851
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 ...201121813721
ceftaroline: a new cephalosporin with activity against methicillin-resistant staphylococcus aureus (mrsa).microbial resistance has reached alarming levels, threatening to outpace the ability to counter with more potent antimicrobial agents. in particular, methicillin-resistant staphylococcus aureus (mrsa) has become a leading cause of skin and soft-tissue infections and pvl-positive strains have been associated with necrotizing pneumonia. increasing reports of growing resistance to glycopeptides have been noted, further limiting the efficacy of standard antibiotics, such as vancomycin. ceftaroline i ...201121785568
retrospective and prospective verification of the cepheid xpert flu assay.we performed a retrospective (n=121) and prospective (n=305) verification of the cepheid xpert flu assay to determine its performance characteristics. the overall sensitivity and specificity were 93% and 100%, respectively. nasopharyngeal specimen sensitivities were 100% for seasonal influenza a/h1 and influenza a/h3, 90% for influenza a/2009/h1n1, and 95% for influenza b.201121775544
the ph-regulated antigen 1 of candida albicans binds the human complement inhibitor c4b-binding protein and mediates fungal complement evasion.candida albicans binds and utilizes human complement inhibitors, such as c4b-binding protein (c4bp), factor h, and fhl-1 for immune evasion. here, we identify candida ph-regulated antigen 1 (pra1) as the first fungal c4bp-binding protein. recombinant pra1 binds c4bp, as shown by elisa and isothermal titration calorimetry, and the pra1-c4bp interaction is ionic in nature. the pra1 binding domains within c4bp were localized to the complement control protein domain 4 (ccp4), ccp7, and ccp8. c4bp bo ...201121212281
Refresh
firstprev
...31323334353637383940...
nextlast
Displaying items 3801 - 3900 of 5747