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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
mutant lipooligosaccharide-based conjugate vaccine demonstrates a broad-spectrum effectiveness against moraxella catarrhalis.there is no licensed vaccine available against moraxella catarrhalis, an exclusive human pathogen responsible for otitis media in children and respiratory infections in adults. we previously developed conjugate vaccine candidates based on lipooligosaccharides (loss) of m. catarrhalis serotypes a, b, and c, each of which was shown to cover a portion of the clinical strains. to generate conserved los antigens and eliminate a potential autoimmune response to a similar epitope between m. catarrhalis ...201121501641
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
in vitro antibacterial activity of modithromycin, a novel 6,11-bridged bicyclolide, against respiratory pathogens, including macrolide-resistant gram-positive cocci.the in vitro activities of modithromycin against gram-positive and -negative respiratory pathogens, including macrolide-resistant cocci with different resistance mechanisms, were compared with those of other macrolide and ketolide agents. mics were determined by the broth microdilution method. all 595 test strains used in this study were isolated from japanese medical facilities. the erm (ribosome methylase) and/or mef (efflux pump) gene, which correlated with resistance to erythromycin as well ...201121220534
divergent mechanisms for passive pneumococcal resistance to β-lactam antibiotics in the presence of haemophilus influenzae.otitis media, for which antibiotic treatment failure is increasingly common, is a leading pediatric public health problem.201121220774
radiological findings in acute haemophilus influenzae pulmonary infection.background: the aim of this study was to assess pulmonary thin-section ct findings in patients with acute haemophilus influenzae pulmonary infection. methods: thin-section ct scans obtained between january 2004 and march 2009 from 434 patients with acute h. influenzae pulmonary infection were retrospectively evaluated. patients with concurrent infection diseases, including streptococcus pneumoniae (n  =  76), staphylococcus aureus (n  =  58) or multiple pathogens were ...201121224303
up-regulation of muc18 in airway epithelial cells by il-13: implications in bacterial adherence.airway bacterial infections are a major problem in lung diseases, including asthma, chronic obstructive pulmonary disease (copd), and cystic fibrosis. increased th2 cytokines, such as il-13, are observed in lung diseases and may contribute to bacterial infections. how th2 cytokines affect bacterial infection remains unknown. muc18, an adhesion molecule shown to be involved in the pathogenesis of malignant melanoma, has been recently identified in airway epithelial cells of patients with copd. we ...201121239604
time-kill activity of the streptogramin nxl 103 against gram-positive and -negative bacteria.against 33 gram-positive and -negative bacteria, nxl 103 mics were 0.03 to 1 μg/ml. nxl 103 was bactericidal by 12 h at 2 × mic against all 5 pneumococci and at 2 × mic after 24 h against all 5 group a and b β-hemolytic streptococci. nxl 103 was bactericidal against all 8 haemophilus influenzae strains at 2 × mic and all 5 moraxella catarrhalis strains at 4 × mic after 24 h but was mainly bacteriostatic against 5 methicillin-resistant staphylococcus aureus strains. after the exposure of one stra ...201121245439
the rtxa toxin gene of kingella kingae: a pertinent target for molecular diagnosis of osteoarticular infections.kingella kingae is an emerging osteoarticular pathogen in young children. its isolation by traditional culture methods remains difficult, underscoring the need to implement other diagnostic methods for its detection and identification, such as nucleic acid amplification tests. although the genome of this bacterium has not yet been sequenced, a toxin named rtx has been identified. the goal of this study was to develop sensitive, specific, and rapid molecular methods based on the rtxa toxin gene s ...201121248099
nontypeable streptococcus pneumoniae as an otopathogen.among 34 streptococcus pneumoniae (spn) sequential isolates from middle ear fluid, we found a case of a nontypeable s. pneumoniae (nt-spn) in a child with acute otitis media (aom). the strain was pneumolysin pcr positive and capsule gene pcr negative. virulence of the nt-spn was confirmed in a chinchilla model of aom.201121251566
in vitro antibiotic susceptibility patterns of bacterial keratitis isolates in oxford, uk: a 10-year review.to analyse the spectrum of bacterial keratitis isolates and their in vitro antibiotic susceptibilities over a 10-year period in oxford, uk; and to compare the in vitro efficacy of ciprofloxacin with that of the combination of gentamicin and cefuroxime over the same period.201121252952
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
comparative analysis and supragenome modeling of twelve moraxella catarrhalis clinical isolates.m. catarrhalis is a gram-negative, gamma-proteobacterium and an opportunistic human pathogen associated with otitis media (om) and exacerbations of chronic obstructive pulmonary disease (copd). with direct and indirect costs for treating these conditions annually exceeding $33 billion in the united states alone, and nearly ubiquitous resistance to beta-lactam antibiotics among m. catarrhalis clinical isolates, a greater understanding of this pathogen's genome and its variability among isolates i ...201121269504
immune evasion of moraxella catarrhalis involves ubiquitous surface protein a-dependent c3d binding.the complement system plays an important role in eliminating invading pathogens. activation of complement results in c3b deposition (opsonization), phagocytosis, anaphylatoxin (c3a, c5a) release, and consequently cell lysis. moraxella catarrhalis is a human respiratory pathogen commonly found in children with otitis media and in adults with chronic obstructive pulmonary disease. the species has evolved multiple complement evasion strategies, which among others involves the ubiquitous surface pro ...201121270401
the second rna chaperone, hfq2, is also required for survival under stress and full virulence of burkholderia cenocepacia j2315.burkholderia cenocepacia j2315 is a highly virulent and epidemic clinical isolate of the b. cepacia complex (bcc), a group of bacteria that have emerged as important pathogens to cystic fibrosis patients. this bacterium, together with all bcc strains and a few other prokaryotes, is unusual for encoding in its genome two distinct and functional hfq-like proteins. in this work, we show results indicating that the 188-amino-acid hfq2 protein is required for the full virulence and stress resistance ...201121278292
pharmacokinetics of solithromycin (cem-101) after single or multiple oral doses and effects of food on single-dose bioavailability in healthy adult subjects.the pharmacokinetics of orally administered solithromycin (cem-101), a novel fluoroketolide, were evaluated in healthy subjects in three phase 1 studies. in two randomized, double-blinded, placebo-controlled studies, escalating single oral doses of solithromycin (50 to 1,600 mg) or seven oral daily doses (200 to 600 mg) of solithromycin were administered. a third study evaluated the effects of food on the bioavailability of single oral doses (400 mg) of solithromycin. following single doses, the ...201121282444
use of ompu porins for attachment and invasion of crassostrea gigas immune cells by the oyster pathogen vibrio splendidus.ompu porins are increasingly recognized as key determinants of pathogenic host vibrio interactions. although mechanisms remain incompletely understood, various species, including the human pathogen vibrio cholera, require ompu for host colonization and virulence. we have shown previously that ompu is essential for virulence in the oyster pathogen vibrio splendidus lgp32. here, we showed that v. splendidus lgp32 invades the oyster immune cells, the hemocytes, through subversion of host-cell actin ...201121282662
microbial communities of the upper respiratory tract and otitis media in children.streptococcus pneumoniae asymptomatically colonizes the upper respiratory tract of children and is a frequent cause of otitis media. patterns of microbial colonization likely influence s. pneumoniae colonization and otitis media susceptibility. this study compared microbial communities in children with and without otitis media. nasal swabs and clinical and demographic data were collected in a cross-sectional study of philadelphia, pa, children (6 to 78 months) (n=108) during the 2008-2009 winter ...201121285435
in vitro antibacterial activity of ceftobiprole against clinical isolates from french teaching hospitals: proposition of zone diameter breakpoints.the aims of this study were to determine the in vitro activity profile of ceftobiprole, a pyrrolidinone cephalosporin, against a large number of bacterial pathogens and to propose zone diameter breakpoints for clinical categorisation according to the european committee on antimicrobial susceptibility testing (eucast) minimum inhibitory concentration (mic) breakpoints. mics of ceftobiprole were determined by broth microdilution against 1548 clinical isolates collected in eight french hospitals. d ...201121295447
structural variations within the transferrin binding site on transferrin-binding protein b, tbpb.pathogenic bacteria acquire the essential element iron through specialized uptake pathways that are necessary in the iron-limiting environments of the host. members of the gram-negative neisseriaceae and pasteurellaceae families have adapted to acquire iron from the host iron binding glycoprotein, transferrin (tf), through a receptor complex comprised of transferring-binding protein (tbp) a and b. because of the critical role they play in the host, these surface-exposed proteins are invariably p ...201121297163
neisseria meningitidis has two independent modes of recognizing its human receptor ceacam1.several human-restricted gram-negative bacteria exploit carcinoembryonic antigen-related cell adhesion molecules (ceacams) for host colonization. for example, neisseria meningitidis engages these human receptors via outer membrane proteins of the colony opacity-associated (opa) protein family triggering internalization into non-phagocytic cells.201121298042
a multicentre surveillance study on the characteristics, bacterial aetiologies and in vitro antibiotic susceptibilities in patients with acute exacerbations of chronic bronchitis.antimicrobial resistance is a global problem and the prevalence is high in many asian countries.201121299688
a novel immunity system for bacterial nucleic acid degrading toxins and its recruitment in various eukaryotic and dna viral systems.the use of nucleases as toxins for defense, offense or addiction of selfish elements is widely encountered across all life forms. using sensitive sequence profile analysis methods, we characterize a novel superfamily (the sukh superfamily) that unites a diverse group of proteins including smi1/knr4, pgs2, fbxo3, skip16, syd, herpesviral us22, irs1 and trs1, and their bacterial homologs. using contextual analysis we present evidence that the bacterial members of this superfamily are potential imm ...201121306995
adenoid reservoir for pathogenic biofilm bacteria.biofilms of pathogenic bacteria are present on the middle ear mucosa of children with chronic otitis media (com) and may contribute to the persistence of pathogens and the recalcitrance of com to antibiotic treatment. controlled studies indicate that adenoidectomy is effective in the treatment of com, suggesting that the adenoids may act as a reservoir for com pathogens. to investigate the bacterial community in the adenoid, samples were obtained from 35 children undergoing adenoidectomy for chr ...201121307211
investigation of the human pathogen acinetobacter baumannii under iron limiting conditions.iron acquisition systems are important virulence factors in pathogenic bacteria. to identify these systems in acinetobacter baumannii, the transcriptomic response of the completely sequenced strain atcc 17978 under iron limiting conditions was investigated using a genomic microarray that contained probes for all annotated open reading frames.201121342532
multistep resistance development studies of ceftaroline in gram-positive and -negative bacteria.ceftaroline, the active component of the prodrug ceftaroline fosamil, is a novel broad-spectrum cephalosporin with bactericidal activity against gram-positive and -negative isolates. this study evaluated the potential for ceftaroline and comparator antibiotics to select for clones of streptococcus pneumoniae, streptococcus pyogenes, haemophilus influenzae, moraxella catarrhalis, klebsiella pneumoniae, staphylococcus aureus, and enterococcus faecalis with elevated mics. s. pneumoniae and s. pyoge ...201121343467
antibiogram pattern of moraxella catarrhalis isolates in acute exacerbation chronic obstructive pulmonary disease. 201121346354
mechanisms of bacterial resistance to antibiotics in infections of copd patients.a key characteristic of airway inflammation in chronic obstructive pulmonary disease (copd) is the persistent presence of bacteria in the lower airways. the most commonly isolated bacteria in the lower respiratory tract of copd patients are nontypeable haemophilus influenzae, moraxella catarrhalis and streptococcus pneumoniae, with growing evidence of the significance of pseudomonas aeruginosa infections in severe copd disease. this review focuses on the antibiotic resistant mechanisms associate ...201121194403
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
non-typeable haemophilus influenzae and streptococcus pneumoniae as primary causes of acute otitis media in colombian children: a prospective study.acute otitis media (aom) is one of the most frequently encountered bacterial infections in children aged < 5 years; streptococcus pneumoniae (s. pneumoniae) and non-typeable haemophilus influenzae (nthi) are historically identified as primary aom causes. nevertheless, recent data on bacterial pathogens causing aom in latin america are limited. this prospective study aimed to identify and characterize bacterial etiology and serotypes of aom cases including antimicrobial susceptibility in < 5 year ...201121208431
tissue factor pathway inhibitor and bacterial infection.see also van den boogaard fe, brands x, schultz mj, levi m, roelofs jjth, van 't veer c, van der poll t. recombinant human tissue factor pathway inhibitor exerts anticoagulant, anti-inflammatory and antimicrobial effects in murine pneumococcal pneumonia. this issue, pp 122-32.201121210950
novel method for non-invasive induction of a middle-ear biofilm in the rat.otitis media and other middle ear diseases are extremely common among all children worldwide. chronic otitis media is strongly associated with the presence of a bacterial middle ear biofilm, which if left untreated, may result in hearing loss or delays in the development of speech and language. many animal models and methods used to study the progression of various middle ear diseases exist. however, there are no reported approaches to biofilm induction in which this infectious process can be in ...201121211589
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
vaccine candidate p6 of nontypable haemophilus influenzae is not a transmembrane protein based on protein structural analysis.p6 has been a vaccine candidate for nontypable haemophilus influenzae (nthi) based on its location on the outer membrane and immunogenicity. because p6 is attached to the inner peptidoglycan layer of nthi, and is putatively surface exposed, it must be a transmembrane protein. we examined the p6 structure using computational modeling, site-directed mutagenesis, and nuclear magnetic resonance spectroscopy. we found that p6 cannot be a transmembrane protein, and therefore may not be surface exposed ...201121215345
moraxella catarrhalis - pathogen or commensal?moraxella catarrhalis is an exclusively human commensal and mucosal pathogen. its role as a disease-causing organism has long been questioned. today, it is recognized as one of the major causes of acute otitis media in children, and its relative frequency of isolation from both the nasopharynx and the middle ear cavity has increased since the introduction of the heptavalent pneumococcal conjugate vaccine, which is associated with a shift in the composition of the nasopharyngeal flora in infants ...201121120723
antibacterial activity of carbapenems against clinical isolates of respiratory bacterial pathogens in the northeastern region of japan in 2007.as the increasing prevalence of resistant strains of respiratory bacterial pathogens has recently been reported, continuous monitoring of the susceptibility of clinical isolates to antibacterial agents is important. we performed a surveillance study focusing on the susceptibility of major respiratory bacterial pathogens in the northeastern region of japan to carbapenems and control drugs. a total of 168 bacterial strains isolated from patients with respiratory tract infections in 2007 were colle ...201120839026
colonization of healthy children by moraxella catarrhalis is characterized by genotype heterogeneity, virulence gene diversity and co-colonization with haemophilus influenzae.the colonization dynamics of moraxella catarrhalis were studied in a population comprising 1079 healthy children living in rotterdam, the netherlands (the generation r focus cohort). a total of 2751 nasal swabs were obtained during four clinic visits timed to take place at 1.5, 6, 14 and 24 months of age, yielding a total of 709 m. catarrhalis and 621 haemophilus influenzae isolates. between january 2004 and december 2006, approximate but regular 6-monthly cycles of colonization were observed, w ...201120847012
chronic granulomatous disease: a review of the infectious and inflammatory complications.abstract: chronic granulomatous disease is the most commonly encountered immunodeficiency involving the phagocyte, and is characterized by repeated infections with bacterial and fungal pathogens, as well as the formation of granulomas in tissue. the disease is the result of a disorder of the nadph oxidase system, culminating in an inability of the phagocyte to generate superoxide, leading to the defective killing of pathogenic organisms. this can lead to infections with staphylococcus aureus, ps ...201121624140
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
a prospective study of intrafamilial transmission and antimicrobial susceptibility for moraxella catarrhalis.moraxella catarrhalis has been recognized as a particularly threatening respiratory tract pathogen in humans. a prospective study was performed to investigate a possible model of m. catarrhalis that can be transmitted intrafamily, which includes features of antimicrobial susceptibility. a total of 75 strains were isolated from 6 participants between july 2002 and february 2004, which included 73 that were verified as beta-lactamase-producing strains. antimicrobial susceptibility was tested for 6 ...201121668485
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
effects of a tumor necrosis factor-a antagonist on experimentally induced rhinosinusitis.this prospective, randomized, and controlled study examined the effects of tumor necrosis factor soluble receptor type i (stnfri, a tnf-a antagonist) on experimentally induced rhinosinusitis in rats. the experimental groups received an instillation of lipopolysaccharide (lps) plus an intramuscular injection of amoxicillin/clavulanate (antibiotic group), an instillation of stnfri (stnfri group), an instillation of stnfri and an injection of amoxicillin/clavulanate (stnfri/antibiotic group), or no ...201121772791
rapid concentration and molecular enrichment approach for sensitive detection of escherichia coli/shigella in potable water samples.in this work, we used a rapid, simple, and efficient concentration and recovery procedure combined with a dna enrichment method (dubbed crename), that we coupled to an escherichia coli/shigella-specific real-time pcr (rtpcr) assay targeting the tuf gene, to sensitively detect e. coli/shigella in water. this integrated method was compared to the usepa culture-based method 1604 on mi agar in terms of analytical specificity, ubiquity, detection limit, and rapidity. none of the 179 non-e. coli/shige ...201121764965
horizontal gene transfer/assortative recombination within the acinetobacter baumannii clinical population provides genetic diversity at the single caro gene encoding a major outer membrane protein channel.we described previously the presence in acinetobacter baumannii of a novel outer membrane (om) protein, caro, which functions as an l-ornithine om channel and whose loss was concomitant with increased carbapenem resistance among clonally related nosocomial isolates of this opportunistic pathogen. here, we describe the existence of extensive genetic diversity at the caro gene within the a. baumannii clinical population. the systematic analysis of caro sequences from a. baumannii isolates obtained ...201121764928
frontline chemoimmunotherapy with fludarabine, cyclophosphamide, alemtuzumab, and rituximab (cfar) for high-risk chronic lymphocytic leukemia.frontline chemoimmunotherapy with fludarabine (f), cyclophosphamide (c) and rituximab (r) is associated with superior overall survival (os) for patients (pts) with cll. alemtuzumab (a) was added to fcr (cfar) in a phase ii trial for high-risk untreated pts <70 years with serum ß-2 microglobulin (ß2m) =4 mg/l. sixty pts were enrolled; median age was 59 yrs (range, 42-69); 75% were male; median ß2m was 5.1 mg/l (range, 4-11.6); and 51% were rai iii-iv. complete remission (cr) was achieved in 70%, ...201121750315
methicillin-resistant staphylococcus aureus and methicillin-susceptible s. aureus pneumonia: comparison of clinical and thin-section ct findings.objectives: the purpose of this study was to compare the clinical and thin-section ct findings in patients with methicillin-resistant staphylococcus aureus (mrsa) and methicillin-susceptible s. aureus (mssa). methods: we retrospectively identified 201 patients with acute mrsa pneumonia and 164 patients with acute mssa pneumonia who had undergone chest thin-section ct examinations between january 2004 and march 2009. patients with concurrent infectious disease were excluded from our study. conseq ...201121750126
molecular investigations of pena-mediated ß-lactam resistance in burkholderia pseudomallei.burkholderia pseudomallei is the etiological agent of melioidosis. because of the bacterium's intrinsic resistance and propensity to establish latent infections, melioidosis therapy is complicated and prolonged. newer generation ß-lactams, specifically ceftazidime, are used for acute phase therapy, but resistance to this cephalosporin has been observed. the chromosomally encoded pena gene encodes a putative twin arginine translocase (tat)-secreted ß-lactamase, and pena mutations have been implic ...201121747814
physiologic cold shock of moraxella catarrhalis affects the expression of genes involved in the iron acquisition, serum resistance and immune evasion.abstract:201121838871
incorporation of real-time pcr into routine public health surveillance of culture negative bacterial meningitis in s+úo paulo, brazil.real-time (rt)-pcr increases diagnostic yield for bacterial meningitis and is ideal for incorporation into routine surveillance in a developing country. we validated a multiplex rt-pcr assay for streptococcus pneumoniae, neisseria meningitidis, and haemophilus influenzae in brazil. risk factors for being culture-negative, rt-pcr positive were determined. the sensitivity of rt-pcr in cerebrospinal fluid (csf) was 100% (95% confidence limits, 96.0%-100%) for n. meningitidis, 97.8% (85.5%-99.9%) fo ...201121731621
toxin on a stick: modular cdi toxin delivery systems play roles in bacterial competition.contact-dependent growth inhibition (cdi) is the first contact-dependent competition system identified in bacteria. cdi is mediated by the cdia/cdib two-partner secretion system, and the bama outer membrane protein serves as the cdi receptor on target cells. a small immunity protein, cdii, is required to protect inhibitor cells from their own cdi system. recent results from our group show that cdi systems are present in a number of important gram-negative plant and animal pathogens. the c-termin ...201121705856
the mut056399 inhibitor of fabi is a new antistaphylococcal compound.mut056399 is a highly potent new inhibitor of the fabi enzyme of both s. aureus and e. coli. in vitro, mut056399 was very active against s. aureus strains including mssa, mrsa, linezolid-resistant and multi-drug-resistant strains, with mic(90) between 0.03 and 0.12 ++g/ml. mut056399 was also active against coagulase negative staphylococci, with mic(90) between 0.12 and 4 ++g/ml. the antibacterial spectrum is consistent with specific fabi inhibition with no activity against bacteria using fabk bu ...201121825292
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
ceftaroline versus ceftriaxone in a highly penicillin-resistant pneumococcal pneumonia rabbit model using simulated human dosing.ceftaroline (cpt) is a new cephalosporin exhibiting bactericidal activity against gram-positive organisms, including methicillin-resistant staphylococcus aureus (mrsa) and multidrug-resistant streptococcus pneumoniae (mdrsp), as well as common gram-negative pathogens. this study investigated in vivo efficacy of a 48-hour simulated human-dose regimen of cpt compared with ceftriaxone (cro) against isolates of s. pneumoniae varying in susceptibility to penicillin in a rabbit pneumonia model. three ...201121576444
investigating the potential of conserved inner core oligosaccharide regions of moraxella catarrhalis lipopolysaccharide as vaccine antigens: accessibility and functional activity of monoclonal antibodies and glycoconjugate derived sera.we investigated the conservation and antibody accessibility of inner core epitopes of moraxella catarrhalis lipopolysaccharide (lps) in order to assess their potential as vaccine candidates. two lps mutants, a single mutant designated lgt2 and a double mutant termed lgt2/lgt4, elaborating truncated inner core structures were generated in order to preclude expression of host-like outer core structures and to create an inner core structure that was shared by all three serotypes a, b and c of m. ca ...201121590368
evaluation of a single tube multiplex real-time pcr for differentiation of the mycobacterium tuberculosis complex in clinical specimens.members of the mycobacterium tuberculosis complex (mtbc) differ in virulence attributes, drug resistance patterns, and host preferences. the rapid differentiation of these species to determine zoonotic or human sources of tuberculosis disease or to direct treatment can benefit both public health and patient management. commercially available assays cannot differentiate these species and published assays have not been evaluated directly on clinical specimens. a real-time pcr assay for the differe ...201121593269
crowding and other strong predictors of upper respiratory tract carriage of otitis media-related bacteria in australian aboriginal and non-aboriginal children.background:: streptococcus pneumoniae, moraxella catarrhalis, and nontypeable haemophilus influenzae is associated with otitis media (om). data are limited on risk factors for carriage of these pathogens, particularly for indigenous populations. we investigated predictors of nasopharyngeal carriage in australian aboriginal and non-aboriginal children. methods:: nasopharyngeal aspirates were collected up to 7 times before age 2 years from 100 aboriginal and 180 non-aboriginal children. longitudin ...201121593705
extracellular matrix formation enhances the ability of streptococcus pneumoniae to cause invasive disease.during infection, pneumococci exist mainly in sessile biofilms rather than in planktonic form, except during sepsis. however, relatively little is known about how biofilms contribute to pneumococcal pathogenesis. here, we carried out a biofilm assay on opaque and transparent variants of a clinical serotype 19f strain wch159. after 4 days incubation, scanning electron microscopy revealed that opaque biofilm bacteria produced an extracellular matrix, whereas the transparent variant did not. the op ...201121611130
exacerbation of cigarette smoke-induced pulmonary inflammation by staphylococcus aureus enterotoxin b in mice.abstract: background: cigarette smoke (cs) is a major risk factor for the development of copd. cs exposure is associated with an increased risk of bacterial colonization and respiratory tract infection, because of suppressed antibacterial activities of the immune system and delayed clearance of microbial agents from the lungs. colonization with staphylococcus aureus results in release of virulent enterotoxins, with superantigen activity which causes t cell activation. objective: to study the eff ...201121615971
intragenomic and intraspecific heterogeneity of the 16s rrna gene in seven bacterial species from the respiratory tract of cystic fibrosis patients assessed by pcr-temporal temperature gel electrophoresis.16s rrna gene-based cultivation-independent methods are increasingly used to study the diversity of microbiota during health and disease. one bias of these methods is the variability of 16s rrna gene that may exist among strains of a same species (intraspecific heterogeneity) or between rrs copies in a genome (intragenomic heterogeneity). we evaluated the level of intraspecific and intragenomic 16s rdna variability in seven species frequently encountered in respiratory tract samples in cystic fi ...201121621347
effects of bacterial infection on airway antimicrobial peptides and proteins in copd.pathogenic bacteria colonize the airways of 30% to 40% of patients with copd and cause approximately 50% of exacerbations. new strains of nontypeable haemophilus influenzae (nthi) and moraxella catarrhalis are associated with exacerbations. antimicrobial protein/peptides (amps) play important roles in innate lung defense against pathogens. to our knowledge, the changes in amp baseline levels in respiratory secretions during bacterial colonization and exacerbation have not been described. the obj ...201121349930
microbial manipulation of receptor crosstalk in innate immunity.in the arms race of host-microbe co-evolution, successful microbial pathogens have evolved ingenious ways to evade host immune responses. in this review, we focus on 'crosstalk manipulation' - the microbial strategies that instigate, subvert or disrupt the molecular signalling crosstalk between receptors of the innate immune system. this proactive interference undermines host defences and contributes to microbial adaptive fitness and persistent infections. understanding how pathogens exploit hos ...201121350579
inhibitory activity of a standardized elderberry liquid extract against clinically-relevant human respiratory bacterial pathogens and influenza a and b viruses.black elderberries (sambucus nigra l.) are well known as supportive agents against common cold and influenza. it is further known that bacterial super-infection during an influenza virus (iv) infection can lead to severe pneumonia. we have analyzed a standardized elderberry extract (rubini, berrypharma ag) for its antimicrobial and antiviral activity using the microtitre broth micro-dilution assay against three gram-positive bacteria and one gram-negative bacteria responsible for infections of t ...201121352539
modified real-time pcr for detecting, differentiating, and quantifying ureaplasma urealyticum and ureaplasma parvum.we evaluated a previously described quantitative real-time pcr (qpcr) for quantifying and differentiating ureaplasma parvum and u. urealyticum. because of nonspecific reactions with staphylococcus aureus dna in the u. parvum pcr, we developed a modified qpcr and designed new primers. these oligonucleotides eradicated cross-reactions, indicating higher specificity. the detection limits of the qpcr were determined at 1 and 3 colony-forming units/ml for u. parvum and u. urealyticum, respectively. t ...201121354056
detection of nasba amplified bacterial tmrna molecules on slicsel designed microarray probes.we present a comprehensive technological solution for bacterial diagnostics using tmrna as a marker molecule. a robust probe design algorithm for microbial detection microarray is implemented. the probes were evaluated for specificity and, combined with nasba (nucleic acid sequence based amplification) amplification, for sensitivity.201121356118
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
exploring the oral microbiota of children at various developmental stages of their dentition in the relation to their oral health.an understanding of the relation of commensal microbiota to health is essential in preventing disease. here we studied the oral microbial composition of children (n = 74, aged 3 - 18 years) in natural transition from their deciduous to a permanent dentition and related the microbial profiles to their oral health status. the microbial composition of saliva was assessed by barcoded pyrosequencing of the v5-v6 hypervariable regions of the 16 s rrna, as well as by using phylogenetic microarrays.201121371338
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
molecular analysis improves pathogen identification and epidemiologic study of pediatric parapneumonic empyema.parapneumonic empyema (ppe) is an increasingly common complication of bacterial pneumonia. epidemiologic study is complicated by the low frequency of positive cultures. we sought to describe the epidemiology of ppe in children using molecular analysis of pleural fluid.201121057372
early acquisition and high nasopharyngeal co-colonisation by streptococcus pneumoniae and three respiratory pathogens amongst gambian new-borns and infants.although haemophilus influenzae type b (hib), staphylococcus aureus and moraxella catarrhalis are important causes of invasive and mucosal bacterial disease among children, co-carriage with streptococcus pneumoniae during infancy has not been determined in west africa.201121689403
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