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comparison of pcr/electron spray ionization-time-of-flight-mass spectrometry versus traditional clinical microbiology for active surveillance of organisms contaminating high-use surfaces in a burn intensive care unit, an orthopedic ward and healthcare workers.understanding nosocomial pathogen transmission is restricted by culture limitations. novel platforms, such as pcr-based electron spray ionization-time-of-flight-mass spectrometry (esi-tof-ms), may be useful as investigational tools.201223050585
the effect of infection order of porcine circovirus type 2 and porcine reproductive and respiratory syndrome virus on dually infected swine alveolar macrophages.concurrent infection with porcine circovirus type 2 (pcv2) and porcine reproductive and respiratory syndrome virus (prrsv) is known as one of the major causes for porcine respiratory disease complex (prdc). dual infection with pcv2 and prrsv is consistently to have more severe clinical presentations and pulmonary lesions than infection with pcv2 alone or prrsv alone. however, it is not known if dual infections with pcv2 and prrsv in different infection order may lead to different clinical sympto ...201223009687
many neglected tropical diseases may have originated in the paleolithic or before: new insights from genetics.the standard view of modern human infectious diseases is that many of them arose during the neolithic when animals were first domesticated, or afterwards. here we review recent genetic and molecular clock estimates that point to a much older paleolithic origin (2.5 million years ago to 10,000 years ago) of some of these diseases. during part of this ancient period our early human ancestors were still isolated in africa. we also discuss the need for investigations of the origin of these diseases ...201222479653
a novel tetravalent leptospira bacterin protects against infection and shedding following challenge in dogs.recent evidence based on the current epidemiological situation suggests that vaccines against canine leptospirosis in europe should be directed against infection with leptospira interrogans (sensu lato) serogroups canicola, icterohaemorrhagiae, grippotyphosa and australis. in the eight studies presented here, dogs were vaccinated with nobivac l4 (msd animal health), a new tetravalent inactivated vaccine containing antigen from four strains representing these four serogroups. the dogs were then c ...201223180149
a novel tetravalent leptospira bacterin protects against infection and shedding following challenge in dogs.recent evidence based on the current epidemiological situation suggests that vaccines against canine leptospirosis in europe should be directed against infection with leptospira interrogans (sensu lato) serogroups canicola, icterohaemorrhagiae, grippotyphosa and australis. in the eight studies presented here, dogs were vaccinated with nobivac l4 (msd animal health), a new tetravalent inactivated vaccine containing antigen from four strains representing these four serogroups. the dogs were then c ...201223180149
the structure- and metal-dependent activity of escherichia coli pgab provides insight into the partial de-n-acetylation of poly-β-1,6-n-acetyl-d-glucosamine.exopolysaccharides are required for the development and integrity of biofilms produced by a wide variety of bacteria. in escherichia coli, partial de-n-acetylation of the exopolysaccharide poly-β-1,6-n-acetyl-d-glucosamine (pnag) by the periplasmic protein pgab is required for polysaccharide intercellular adhesin-dependent biofilm formation. to understand the molecular basis for pnag de-n-acetylation, the structure of pgab in complex with ni(2+) and fe(3+) have been determined to 1.9 and 2.1 å r ...201222810235
synthetic oligosaccharides as tools to demonstrate cross-reactivity between polysaccharide antigens.escherichia coli o148 is a nonencapsulated enterotoxigenic (etec) gram negative bacterium that can cause diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome in humans. the surface-exposed o-specific polysaccharide (o-sp) of the lipopolysaccharide of this bacterium is considered both a virulence factor and a protective antigen. it is built up of the linear tetrasaccharide repeating unit [3)-α-l-rhap-(1→2)-α-d-glcp-(1→3)-α-d-glcnacp-(1→3)-α-l-rhap-(1→] differing from that of the o-sp of s ...201222713129
type v secretion: mechanism(s) of autotransport through the bacterial outer membrane.autotransport in gram-negative bacteria denotes the ability of surface-localized proteins to cross the outer membrane (om) autonomously. autotransporters perform this task with the help of a β-barrel transmembrane domain localized in the om. different classes of autotransporters have been investigated in detail in recent years; classical monomeric but also trimeric autotransporters comprise many important bacterial virulence factors. so do the two-partner secretion systems, which are a special c ...201222411980
the standard european vector architecture (seva): a coherent platform for the analysis and deployment of complex prokaryotic phenotypes.the 'standard european vector architecture' database (seva-db, http://seva.cnb.csic.es) was conceived as a user-friendly, web-based resource and a material clone repository to assist in the choice of optimal plasmid vectors for de-constructing and re-constructing complex prokaryotic phenotypes. the seva-db adopts simple design concepts that facilitate the swapping of functional modules and the extension of genome engineering options to microorganisms beyond typical laboratory strains. under the ...201223180763
the standard european vector architecture (seva): a coherent platform for the analysis and deployment of complex prokaryotic phenotypes.the 'standard european vector architecture' database (seva-db, http://seva.cnb.csic.es) was conceived as a user-friendly, web-based resource and a material clone repository to assist in the choice of optimal plasmid vectors for de-constructing and re-constructing complex prokaryotic phenotypes. the seva-db adopts simple design concepts that facilitate the swapping of functional modules and the extension of genome engineering options to microorganisms beyond typical laboratory strains. under the ...201223180763
flagella from five cronobacter species induce pro-inflammatory cytokines in macrophage derivatives from human monocytes.cronobacter spp. are opportunistic pathogens linked to lie-threatening infections in neonates and contaminated powdered infant formula that has been epidemiologically associated with these cases. clinical symptoms of cronobacter include necrotizing enterocolitis, bacteremia, and meningitis. flagella from c. sakazakii are involved in biofilm formation and its adhesion to epithelial cells. we investigated the role of flagella from c. sakazakii st1 and st4, c. malonaticus, c. muytjensii, c. turicen ...201223284883
expression of multidrug resistance efflux pump gene nora is iron responsive in staphylococcus aureus.staphylococcus aureus utilizes efflux transporter nora to pump out a wide range of structurally dissimilar drugs, conferring low-level multidrug resistance. the regulation of nora expression has yet to be fully understood although past studies have revealed that this gene is under the control of the global transcriptional regulator mgra and the two-component system arlrs. to identify additional regulators of nora, we screened a transposon library in strain newman expressing the transcriptional f ...201222267518
role of escp (orf16) in injectisome biogenesis and regulation of type iii protein secretion in enteropathogenic escherichia coli.enteropathogenic escherichia coli employs a type iii secretion system (t3ss) to translocate virulence effector proteins directly into enterocyte host cells, leading to diarrheal disease. the t3ss is encoded within the chromosomal locus of enterocyte effacement (lee). the function of some of the lee-encoded proteins remains unknown. here we investigated the role of the orf16 protein in t3ss biogenesis and function. an orf16 deletion mutant showed translocator and effector protein secretion profil ...201222923600
a type vi secretion system encoding locus is required for bordetella bronchiseptica immunomodulation and persistence in vivo.type vi secretion systems (t6sss) have been identified in numerous gram-negative pathogens, but the lack of a natural host infection model has limited analysis of t6ss contributions to infection and pathogenesis. here, we describe disruption of a gene within locus encoding a putative t6ss in bordetella bronchiseptica strain rb50, a respiratory pathogen that circulates in a broad range of mammals, including humans, domestic animals, and mice. the 26 gene locus encoding the b. bronchiseptica t6ss ...201223071529
inhibition of protein synthesis on the ribosome by tildipirosin compared with other veterinary macrolides.tildipirosin is a 16-membered-ring macrolide developed to treat bacterial pathogens, including mannheimia haemolytica and pasteurella multocida, that cause respiratory tract infections in cattle and swine. here we evaluated the efficacy of tildipirosin at inhibiting protein synthesis on the ribosome (50% inhibitory concentration [ic(50)], 0.23 ± 0.01 μm) and compared it with the established veterinary macrolides tylosin, tilmicosin, and tulathromycin. mutation and methylation at key rrna nucleot ...201222926570
biocatalyst development by directed evolution.biocatalysis has emerged as a great addition to traditional chemical processes for production of bulk chemicals and pharmaceuticals. to overcome the limitations of naturally occurring enzymes, directed evolution has become the most important tool for improving critical traits of biocatalysts such as thermostability, activity, selectivity, and tolerance towards organic solvents for industrial applications. recent advances in mutant library creation and high-throughput screening have greatly facil ...201222310212
surveillance cultures of samples obtained from biopsy channels and automated endoscope reprocessors after high-level disinfection of gastrointestinal endoscopes.the instrument channels of gastrointestinal (gi) endoscopes may be heavily contaminated with bacteria even after high-level disinfection (hld). the british society of gastroenterology guidelines emphasize the benefits of manually brushing endoscope channels and using automated endoscope reprocessors (aers) for disinfecting endoscopes. in this study, we aimed to assess the effectiveness of decontamination using reprocessors after hld by comparing the cultured samples obtained from biopsy channels ...201222943739
the multifaceted roles of neutrophil gelatinase associated lipocalin (ngal) in inflammation and cancer.neutrophil gelatinase associated lipocalin (ngal), also known as oncogene 24p3, uterocalin, siderocalin or lipocalin 2, is a 24kda secreted glycoprotein originally purified from a culture of mouse kidney cells infected with simian virus 40 (sv-40). subsequent investigations have revealed that it is a member of the lipocalin family of proteins that transport small, hydrophobic ligands. since then, ngal expression has been reported in several normal tissues where it serves to provide protection ag ...201222513004
characterization of a novel agrobacterium tumefaciens galactarolactone cycloisomerase enzyme for direct conversion of d-galactarolactone to 3-deoxy-2-keto-l-threo-hexarate.microorganisms use different pathways for d-galacturonate catabolism. in the known microbial oxidative pathway, d-galacturonate is oxidized to d-galactarolactone, the lactone hydrolyzed to galactarate, which is further converted to 3-deoxy-2-keto-hexarate and α-ketoglutarate. we have shown recently that agrobacterium tumefaciens strain c58 contains an uronate dehydrogenase (at udh) that oxidizes d-galacturonic acid to d-galactarolactone. here we report identification of a novel enzyme from the s ...201222493433
evaluation of the bruker biotyper and vitek ms matrix-assisted laser desorption ionization-time of flight mass spectrometry systems for identification of nonfermenting gram-negative bacilli isolated from cultures from cystic fibrosis patients.the bruker biotyper and vitek ms matrix-assisted laser desorption ionization-time of flight (maldi-tof) mass spectrometry (ms) instruments were evaluated for the identification of nonfermenting gram-negative bacilli (nfgnb) by a blinded comparison to conventional biochemical or molecular methods. two hundred nfgnb that were recovered from cultures from cystic fibrosis patients in the university of iowa health care (uihc) microbiology laboratory between 1 january 2006 and 31 october 2010 were sen ...201222495566
naxd is a deacetylase required for lipid a modification and francisella pathogenesis.modification of specific gram-negative bacterial cell envelope components, such as capsule, o-antigen and lipid a, are often essential for the successful establishment of infection. francisella species express lipid a molecules with unique characteristics involved in circumventing host defences, which significantly contribute to their virulence. in this study, we show that naxd, a member of the highly conserved ydjc superfamily, is a deacetylase required for an important modification of the oute ...201222966934
solitary restriction endonucleases in prokaryotic genomes.prokaryotic restriction-modification (r-m) systems defend the host cell from the invasion of a foreign dna. they comprise two enzymatic activities: specific dna cleavage activity and dna methylation activity preventing cleavage. typically, these activities are provided by two separate enzymes: a dna methyltransferase (mtase) and a restriction endonuclease (re). in the absence of a corresponding mtase, an re of type ii r-m system is highly toxic for the cell. genes of the r-m system are linked in ...201222965118
bacterial cell wall compounds as promising targets of antimicrobial agents i. antimicrobial peptides and lipopolyamines.the first barrier that an antimicrobial agent must overcome when interacting with its target is the microbial cell wall. in the case of gram-negative bacteria, additional to the cytoplasmic membrane and the peptidoglycan layer, an outer membrane (om) is the outermost barrier. the om has an asymmetric distribution of the lipids with phospholipids and lipopolysaccharide (lps) located in the inner and outer leaflets, respectively. in contrast, gram-positive bacteria lack om and possess a much thick ...201222664072
a genetic approach to the development of new therapeutic phages to fight pseudomonas aeruginosa in wound infections.pseudomonas aeruginosa is a frequent participant in wound infections. emergence of multiple antibiotic resistant strains has created significant problems in the treatment of infected wounds. phage therapy (pt) has been proposed as a possible alternative approach. infected wounds are the perfect place for pt applications, since the basic condition for pt is ensured; namely, the direct contact of bacteria and their viruses. plenty of virulent ("lytic") and temperate ("lysogenic") bacteriophages ar ...201223344559
a genetic approach to the development of new therapeutic phages to fight pseudomonas aeruginosa in wound infections.pseudomonas aeruginosa is a frequent participant in wound infections. emergence of multiple antibiotic resistant strains has created significant problems in the treatment of infected wounds. phage therapy (pt) has been proposed as a possible alternative approach. infected wounds are the perfect place for pt applications, since the basic condition for pt is ensured; namely, the direct contact of bacteria and their viruses. plenty of virulent ("lytic") and temperate ("lysogenic") bacteriophages ar ...201223344559
optimization of matrix-assisted laser desorption ionization-time of flight mass spectrometry analysis for bacterial identification.matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) is a relatively new addition to the clinical microbiology laboratory. the performance of the maldi biotyper system (bruker daltonics) was compared to those of phenotypic and genotypic identification methods for 690 routine and referred clinical isolates representing 102 genera and 225 unique species. we systematically compared direct-smear and extraction methods on a taxonomically diverse collection of is ...201222993178
multidrug-resistance and toxic metal tolerance of medically important bacteria isolated from an aquaculture system.the use of antimicrobials and toxic metals should be considered carefully in aquaculture and surrounding environments. we aimed to evaluate medically relevant bacteria in an aquaculture system and their susceptibility to antimicrobials and toxic metals. selective cultures for enterobacteria (ent), non-fermenting gram-negative rods (nfr) and gram-positive cocci (gpc) were obtained from water samples collected in two different year seasons. the isolated bacteria were biochemically identified and a ...201222972388
a multilocus sequence typing scheme implies population structure and reveals several putative novel achromobacter species.the genus achromobacter currently is comprised of seven species, including achromobacter xylosoxidans, an opportunistic and nosocomial pathogen that displays broad-spectrum antimicrobial resistance and is recognized as causing chronic respiratory tract infection in persons with cystic fibrosis (cf). to enable strain typing for global epidemiologic investigations, to clarify the taxonomy of "achromobacter-like" strains, and to elucidate the population structure of this genus, we developed a genus ...201222785192
multilocus sequence analysis of isolates of achromobacter from patients with cystic fibrosis reveals infecting species other than achromobacter xylosoxidans.a multilocus sequence analysis (mlsa) scheme was developed for characterization of strains and species from the genus achromobacter, which are increasingly recovered from patients with cystic fibrosis (cf). five conserved housekeeping genes were selected for the mlsa, which was applied to a diverse collection of 77 strains originating from europe, asia, and south america and including type strains of the seven recognized achromobacter species, six environmental strains, eight non-cf clinical str ...201222675125
developing insights into the mechanisms of evolution of bacterial pathogens from whole-genome sequences.evolution of bacterial pathogen populations has been detected in a variety of ways including phenotypic tests, such as metabolic activity, reaction to antisera and drug resistance and genotypic tests that measure variation in chromosome structure, repetitive loci and individual gene sequences. while informative, these methods only capture a small subset of the total variation and, therefore, have limited resolution. advances in sequencing technologies have made it feasible to capture whole-genom ...201223075447
synthase-dependent exopolysaccharide secretion in gram-negative bacteria.the biosynthesis and export of bacterial cell-surface polysaccharides is known to occur through several distinct mechanisms. recent advances in the biochemistry and structural biology of several proteins in synthase-dependent polysaccharide secretion systems have identified key conserved components of this pathway in gram-negative bacteria. these components include an inner-membrane-embedded polysaccharide synthase, a periplasmic tetratricopeptide repeat (tpr)-containing scaffold protein, and an ...201223117123
synthase-dependent exopolysaccharide secretion in gram-negative bacteria.the biosynthesis and export of bacterial cell-surface polysaccharides is known to occur through several distinct mechanisms. recent advances in the biochemistry and structural biology of several proteins in synthase-dependent polysaccharide secretion systems have identified key conserved components of this pathway in gram-negative bacteria. these components include an inner-membrane-embedded polysaccharide synthase, a periplasmic tetratricopeptide repeat (tpr)-containing scaffold protein, and an ...201223117123
analysis of bacterial biofilms using nmr-based metabolomics.infectious diseases can be difficult to cure, especially if the pathogen forms a biofilm. after decades of extensive research into the morphology, physiology and genomics of biofilm formation, attention has recently been directed toward the analysis of the cellular metabolome in order to understand the transformation of a planktonic cell to a biofilm. metabolomics can play an invaluable role in enhancing our understanding of the underlying biological processes related to the structure, formation ...201222800371
regulation and evolution of malonate and propionate catabolism in proteobacteria.bacteria catabolize malonate via two pathways, encoded by the mdc and mat genes. in various bacteria, transcription of these genes is controlled by the gntr family transcription factors (tfs) matr/mdcy and/or the lysr family transcription factor mdcr. propionate is metabolized via the methylcitrate pathway, comprising enzymes encoded by the prp and acn genes. prpr, the fis family sigma 54-dependent transcription factor, is known to be a transcriptional activator of the prp genes. here, we report ...201222505679
antiadhesive activity of the biosurfactant pseudofactin ii secreted by the arctic bacterium pseudomonas fluorescens bd5.pseudofactin ii is a recently identified biosurfactant secreted by pseudomonas fluorescens bd5, the strain obtained from freshwater from the arctic archipelago of svalbard. pseudofactin ii is a novel compound identified as cyclic lipopeptide with a palmitic acid connected to the terminal amino group of eighth amino acid in peptide moiety. the c-terminal carboxylic group of the last amino acid forms a lactone with the hydroxyl of thr3. adhesion is the first stage of biofilm formation and the best ...201222360895
many stimuli pull the necrotic trigger, an overview.the lab of jürg tschopp was the first to report on the crucial role of receptor-interacting protein kinase 1 (ripk1) in caspase-independent cell death. because of this pioneer finding, regulated necrosis and in particular ripk1/ripk3 kinase-mediated necrosis, referred to as necroptosis, has become an intensively studied form of regulated cell death. although necrosis was identified initially as a backup cell death program when apoptosis is blocked, it is now recognized as a cellular defense mech ...201222075985
many stimuli pull the necrotic trigger, an overview.the lab of jürg tschopp was the first to report on the crucial role of receptor-interacting protein kinase 1 (ripk1) in caspase-independent cell death. because of this pioneer finding, regulated necrosis and in particular ripk1/ripk3 kinase-mediated necrosis, referred to as necroptosis, has become an intensively studied form of regulated cell death. although necrosis was identified initially as a backup cell death program when apoptosis is blocked, it is now recognized as a cellular defense mech ...201222075985
design and application of chitosan microspheres as oral and nasal vaccine carriers: an updated review.chitosan, a natural biodegradable polymer, is of great interest in biomedical research due to its excellent properties including bioavailability, nontoxicity, high charge density, and mucoadhesivity, which creates immense potential for various pharmaceutical applications. it has gelling properties when it interacts with counterions such as sulfates or polyphosphates and when it crosslinks with glutaraldehyde. this characteristic facilitates its usefulness in the coating or entrapment of biochemi ...201223271909
the response regulator sype controls biofilm formation and colonization through phosphorylation of the syp-encoded regulator sypa in vibrio fischeri.bacteria utilize multiple regulatory systems to modulate gene expression in response to environmental changes, including two-component signalling systems and partner-switching networks. we recently identified a novel regulatory protein, sype, that combines features of both signalling systems. sype contains a central response regulator receiver domain flanked by putative kinase and phosphatase effector domains with similarity to partner-switching proteins. sype was previously shown to exert dual ...201223171087
the response regulator sype controls biofilm formation and colonization through phosphorylation of the syp-encoded regulator sypa in vibrio fischeri.bacteria utilize multiple regulatory systems to modulate gene expression in response to environmental changes, including two-component signalling systems and partner-switching networks. we recently identified a novel regulatory protein, sype, that combines features of both signalling systems. sype contains a central response regulator receiver domain flanked by putative kinase and phosphatase effector domains with similarity to partner-switching proteins. sype was previously shown to exert dual ...201223171087
complications of elastase-induced arterial saccular aneurysm in rabbits: case reports and literature review.endoluminal infusion and incubation of elastase with or without collagenase into the rabbit common carotid artery is an established model of arterial saccular aneurysm. the model mimics naturally occurring human cerebral aneurysms in many ways, including histologic and morphologic characteristics, hemodynamic pressures, and shear stresses. however, complications have been associated with the model. here, we report 2 complications: 1) the first known case of iatrogenic laryngeal hemiplegia in a r ...201223561881
tgpa, a protein with a eukaryotic-like transglutaminase domain, plays a critical role in the viability of pseudomonas aeruginosa.the gram-negative bacterium pseudomonas aeruginosa is an important opportunistic pathogen in compromised individuals, such as patients with cystic fibrosis, severe burns or impaired immunity. in this work we aimed to screen novel essential genes of p. aeruginosa by shotgun antisense identification, a technique that was developed a decade ago for the gram-positive bacterium staphylococcus aureus and was under-used in gram-negative bacteria for a considerable period of time. following antisense sc ...201223209712
specific biological diagnoses are needed to determine the durability of pertussis vaccine-induced immunity. 201222871827
identification, expression and activity analyses of five novel duck beta-defensins.in the current study, five novel avian β-defensins (avbds) were identified and characterized in tissues from peking ducks (anas platyrhynchos). the nucleotide sequences of these cdnas comprised 198 bp, 182 bp, 201 bp, 204 bp, and 168 bp, and encoded 65, 60, 66, 67, and 55 amino acids, respectively. homology, characterization and comparison of these genes with avbd from other avian species confirmed that they were apl_avbd1, 3, 5, 6, and 16. recombinant avbds were produced and purified by express ...201223112840
identification of a co2 responsive regulon in bordetella.sensing the environment allows pathogenic bacteria to coordinately regulate gene expression to maximize survival within or outside of a host. here we show that bordetella species regulate virulence factor expression in response to carbon dioxide levels that mimic in vivo conditions within the respiratory tract. we found strains of bordetella bronchiseptica that did not produce adenylate cyclase toxin (act) when grown in liquid or solid media with ambient air aeration, but produced act and additi ...201223112828
electrocardiograms corresponding to the development of myocardial infarction in anesthetized whhlmi rabbits (oryctolagus cuniculus), an animal model for familial hypercholesterolemia.the aim of this study was to determine whether features indicative of myocardial ischemia occur in the electrocardiograms (ecg) in myocardial infarction-prone watanabe heritable hyperlipidemic (whhlmi) rabbits, an animal model for human familial hypercholesterolemia. ecg were recorded in 110 anesthetized whhlmi rabbits (age, 10 to 39 mo) by using unipolar and bipolar limb leads with or without chest leads. we noted the following electrocardiographic changes: t wave inversion (37.4%), st segment ...201223114045
pr-39, a porcine host defence peptide, is prominent in mucosa and lymphatic tissue of the respiratory tract in healthy pigs and pigs infected with actinobacillus pleuropneumoniae.host defence peptides are important components of mammalian innate immunity. we have previously shown that pr-39, a cathelicidin host defence peptide, is an important factor in porcine innate immune mechanisms as a first line of defence after infection with actinobacillus pleuropneumoniae. pr-39 interacts with bacterial and mammalian cells and is involved in a variety of processes such as killing of bacteria and promotion of wound repair. in bronchoalveolar lavage fluid of infected pigs pr-39 co ...201223016650
small mutations in bordetella pertussis are associated with selective sweeps.bordetella pertussis is the causative agent of pertussis, a highly contagious disease of the human respiratory tract. despite high vaccination coverage, pertussis has resurged and has become one of the most prevalent vaccine-preventable diseases in developed countries. we have proposed that both waning immunity and pathogen adaptation have contributed to the persistence and resurgence of pertussis. allelic variation has been found in virulence-associated genes coding for the pertussis toxin a su ...201223029513
gapfiller: a de novo assembly approach to fill the gap within paired reads.next generation sequencing technologies are able to provide high genome coverages at a relatively low cost. however, due to limited reads' length (from 30 bp up to 200 bp), specific bioinformatics problems have become even more difficult to solve. de novo assembly with short reads, for example, is more complicated at least for two reasons: first, the overall amount of "noisy" data to cope with increased and, second, as the reads' length decreases the number of unsolvable repeats grows. our work' ...201223095524
natural and experimental helicobacter pullorum infection in brown norway rats.helicobacter pullorum is an enterohepatic helicobacter species (ehs) that was recently reported as a naturally acquired infection in mice. faecal samples from 18 out of 20 brown norway (bn) rats, housed in the same barrier as the h. pullorum-infected mice, were positive for h. pullorum using species-specific pcr. in addition, we determined whether h. pullorum was able to persistently colonize the gastrointestinal tract and/or biliary tree and elicit tissue inflammation as well as a serum igg res ...201222580914
artifactual changes in sprague-dawley rat hematologic parameters after storage of samples at 3 °c and 21 °c.circumstances can occur that prevent timely analysis of blood samples. the purpose of this study was to characterize artifactual changes in rat hematologic parameters after storage of samples at 3 and 21 °c and to document the effects of storage on peripheral blood smear findings. edta-treated blood samples were collected from 12 male sprague-dawley rats. samples were analyzed on an impedance hematology analyzer within 5 min after collection and then at 6, 24, 48, and 72 h after storage at 3 °c ...201223312091
handling of adolescent rats improves learning and memory and decreases anxiety.some environmental interventions can result in physiologic and behavioral changes in laboratory animals. in this context, the handling of adolescent or adult rodents has been reported to influence exploratory behavior and emotionality. here we examined the effects of handling on memory and anxiety levels of adolescent rats. male sprague-dawley rats (age, 60 d) were divided into a control group and a handled group, which were handled for 5 min daily, 5 d per week, for 6 wk. during handling bouts, ...201223312082
protective immunity conferred by the c-terminal fragment of recombinant pasteurella multocida toxin.pasteurella multocida serogroup d, producing p. multocida toxin (pmt), is a causative pathogen of progressive atrophic rhinitis (par) in swine. to evaluate the protective immunity and vaccination efficacy of the truncated form of pmt, a c-terminal form of recombinant pmt (designated pmt2.3; amino acid residues 505 to 1285 of pmt) was expressed in an escherichia coli expression system, and the humoral and cellular immune responses to pmt2.3 were investigated. pmt2.3 vaccination in mice led to hig ...201222837096
siderocalin/lcn2/ngal/24p3 does not drive apoptosis through gentisic acid mediated iron withdrawal in hematopoietic cell lines.siderocalin (also lipocalin 2, ngal or 24p3) binds iron as complexes with specific siderophores, which are low molecular weight, ferric ion-specific chelators. in innate immunity, siderocalin slows the growth of infecting bacteria by sequestering bacterial ferric siderophores. siderocalin also binds simple catechols, which can serve as siderophores in the damaged urinary tract. siderocalin has also been proposed to alter cellular iron trafficking, for instance, driving apoptosis through iron eff ...201222928018
sige facilitates the adaptation of bordetella bronchiseptica to stress conditions and lethal infection in immunocompromised mice.the cell envelope of a bacterial pathogen can be damaged by harsh conditions in the environment outside a host and by immune factors during infection. cell envelope stress responses preserve the integrity of this essential compartment and are often required for virulence. bordetella species are important respiratory pathogens that possess a large number of putative transcription factors. however, no cell envelope stress responses have been described in these species. among the putative bordetell ...201222897969
peritoneal dialysis associated infections: an update on diagnosis and management.peritoneal dialysis (pd) is associated with a high risk of infection of the peritoneum, subcutaneous tunnel and catheter exit site. although quality standards demand an infection rate < 0.67 episodes/patient/year on dialysis, the reported overall rate of pd associated infection is 0.24-1.66 episodes/patient/year. it is estimated that for every 0.5-per-year increase in peritonitis rate, the risk of death increases by 4% and 18% of the episodes resulted in removal of the pd catheter and 3.5% resul ...201224175248
phenotypic and genomic analysis of hypervirulent human-associated bordetella bronchiseptica.b. bronchiseptica infections are usually associated with wild or domesticated animals, but infrequently with humans. a recent phylogenetic analysis distinguished two distinct b. bronchiseptica subpopulations, designated complexes i and iv. complex iv isolates appear to have a bias for infecting humans; however, little is known regarding their epidemiology, virulence properties, or comparative genomics.201222863321
effects of a diet high in salt, fat, and sugar on telemetric blood pressure measurements in conscious, unrestrained adult yucatan miniature swine (sus scrofa).radiotelemetry was used to evaluate diet-related elevation of blood pressure in adult yucatan miniature swine. systolic arterial blood pressure (sap), diastolic atrial blood pressure (dap), heart rate, and locomotor activity were assessed in 9- or 11-mo-old yucatan miniature pigs fed a standard diet or a north american-type diet high in salt, fat, and sugar (hsfs). compared with pigs fed standard diet, pigs fed hsfs diet showed markedly elevated sap (132 ± 3 compared with 156 ± 6 mm hg), whereas ...201223043781
differences in health status affect susceptibility and mapping of genetic loci for atherosclerosis (fatty streak) in inbred mice.we observed differences in atherosclerosis susceptibility in mouse inbred strains over the years as the health status of our animal rooms increased. therefore, we investigated the effect of animal room health status on atherosclerosis susceptibility in different strains. as these data can also be used for genome-wide association mapping, we performed a mapping study and compared our results with previously found quantitative trait loci for atherosclerosis in mouse and humans.201222837474
similarity analysis, synthesis, and bioassay of antibacterial cyclic peptidomimetics.the chemical similarity of antibacterial cyclic peptides and peptidomimetics was studied in order to identify new promising cyclic scaffolds. a large descriptor space coupled with cluster analysis was employed to digitize known antibacterial structures and to gauge the potential of new peptidomimetic macrocycles, which were conveniently synthesized by acylbenzotriazole methodology. some of the synthesized compounds were tested against an array of microorganisms and showed antibacterial activity ...201223019443
atomic structure of bordetella bacteriophage reveals a jellyroll fold in cementprotein and a topologically distinct hk97-like fold in major capsid protein. 201225197259
the bordetella pertussis model of exquisite gene control by the global transcription factor bvga.bordetella pertussis causes whooping cough, an infectious disease that is reemerging despite widespread vaccination. a more complete understanding of b. pertussis pathogenic mechanisms will involve unravelling the regulation of its impressive arsenal of virulence factors. here we review the action of the b. pertussis response regulator bvga in the context of what is known about bacterial rna polymerase and various modes of transcription activation. at most virulence gene promoters, multiple dime ...201222628479
variation in airway responsiveness of male c57bl/6 mice from 5 vendors.mice are now the most commonly used animal model for the study of asthma. the mouse asthma model has many characteristics of the human pathology, including allergic sensitization and airway hyperresponsiveness. inbred strains are commonly used to avoid variations due to genetic background, but variations due to rearing environment are not as well recognized. after a change in mouse vendors and a switch from c57bl/6j mice to c57bl/6n mice, we noted significant differences in airway responsiveness ...201223043804
multiplex pcr to identify macrolide resistance determinants in mannheimia haemolytica and pasteurella multocida.the bacterial pathogens mannheimia haemolytica and pasteurella multocida are major etiological agents in respiratory tract infections of cattle. although these infections can generally be successfully treated with veterinary macrolide antibiotics, a few recent isolates have shown resistance to these drugs. macrolide resistance in members of the family pasteurellaceae is conferred by combinations of at least three genes: erm(42), which encodes a monomethyltransferase and confers a type i mls(b) ( ...201222564832
the type iii secreted protein bspr regulates the virulence genes in bordetella bronchiseptica.bordetella bronchiseptica is closely related with b. pertussis and b. parapertussis, the causative agents of whooping cough. these pathogenic species share a number of virulence genes, including the gene locus for the type iii secretion system (t3ss) that delivers effector proteins. to identify unknown type iii effectors in bordetella, secreted proteins in the bacterial culture supernatants of wild-type b. bronchiseptica and an isogenic t3ss-deficient mutant were compared with itraq-based, quant ...201222701731
evaluation of a mouse model of necrotic granuloma formation using c3heb/fej mice for testing of drugs against mycobacterium tuberculosis.persistence of mycobacterium tuberculosis remains a significant challenge for the effective treatment of tuberculosis in humans. in animals that develop necrotic lung lesions following infection with m. tuberculosis, drug-tolerant bacilli are present and persist in an extracellular microenvironment within the necrotic cores. in this study, we examined the efficacy of drug treatment in c3heb/fej (kramnik) mice that develop lesions with liquefactive necrosis, in comparison to balb/c mice that deve ...201222470120
contribution of bordetella filamentous hemagglutinin and adenylate cyclase toxin to suppression and evasion of interleukin-17-mediated inflammation.bordetella pertussis and bordetella bronchiseptica establish respiratory infections with notorious efficiency. our previous studies showed that the fhab genes of b. pertussis and b. bronchiseptica, which encode filamentous hemagglutinin (fha), are functionally interchangeable and provided evidence that fha-deficient b. bronchiseptica induces more inflammation in the lungs of mice than wild-type b. bronchiseptica. we show here that the robust inflammatory response to fha-deficient b. bronchisepti ...201222473603
isolation of antibacterial compounds from quercus dilatata l. through bioassay guided fractionation.four medicinal plants (chrozophora hierosolymitana spreng, chrysanthemum leucanthemum l., ephedra gerardiana wall. ex stapf, and quercus dilatata l.) used by indigenous healers to treat various infectious diseases were selected for the present study. the major objective of the present study was isolation and characterization of antimicrobial components from the crude plant extracts using bioassay guided fractionation.201222554280
isolation of a potent antibiotic producer bacterium, especially against mrsa, from northern region of the persian gulf.nowadays, emergence and prevalence of mrsa (methicillin resistant staphylococcus aureus) strain have become a great global concern in 21st century, so, it is necessary to discover new antibiotics against this pathogen. the aim of this study was isolation and evaluation marine bacteria from the persian gulf in order to finding antibiotic compounds against some pathogenic bacteria. for this purpose, water and sediment samples were collected from the persian gulf during march to october 2009. the a ...201222642595
first report of infectious pericarditis due to bordetella holmesii in an adult patient with malignant lymphoma.bordetella holmesii is a fastidious gram-negative rod first identified in 1995. though rare, it is isolated mainly in immunocompromised and asplenic hosts and is associated with bacteremia, pertussis-like respiratory tract infection, and endocarditis. herein, we describe a unique b. holmesii infectious pericarditis patient with malignant lymphoma.201222378902
in vivo pharmacokinetics/pharmacodynamics of colistin and imipenem in pseudomonas aeruginosa biofilm infection.many pseudomonas aeruginosa isolates from the airways of patients with cystic fibrosis (cf) are sensitive to antibiotics in susceptibility testing, but eradication of the infection is difficult. the main reason is the biofilm formation in the airways of patients with cf. the pharmacokinetics (pks) and pharmacodynamics (pds) of antimicrobials can reliably be used to predict whether antimicrobial regimens will achieve the maximum bactericidal effect against infections. unfortunately, however, most ...201222354300
experimental actinobacillus pleuropneumoniae challenge in swine: comparison of computed tomographic and radiographic findings during disease.in pigs, diseases of the respiratory tract like pleuropneumonia due to actinobacillus pleuropneumoniae (app) infection have led to high economic losses for decades. further research on disease pathogenesis, pathogen-host-interactions and new prophylactic and therapeutic approaches are needed. in most studies, a large number of experimental animals are required to assess lung alterations at different stages of the disease. in order to reduce the required number of animals but nevertheless gather ...201222546414
bordetella holmesii in nasopharyngeal samples from chilean patients with suspected bordetella pertussis infection. 201222427606
the promoter architectural landscape of the salmonella phop regulon.the dna-binding protein phop controls virulence and mg²⁺ homeostasis in the gram-negative pathogen salmonella enterica serovar typhimurium. phop regulates expression of a large number of genes that differ both in their ancestry and in the biochemical functions and physiological roles of the encoded products. this suggests that phop-regulated genes are differentially expressed. to understand how a bacterial activator might generate varied gene expression behaviour, we investigated the cis-acting ...201222435712
functional and structural analysis of the siderophore synthetase asbb through reconstitution of the petrobactin biosynthetic pathway from bacillus anthracis.petrobactin, a mixed catechol-carboxylate siderophore, is required for full virulence of bacillus anthracis, the causative agent of anthrax. the asbabcdef operon encodes the biosynthetic machinery for this secondary metabolite. here, we show that the function of five gene products encoded by the asb operon is necessary and sufficient for conversion of endogenous precursors to petrobactin using an in vitro system. in this pathway, the siderophore synthetase asbb catalyzes formation of amide bonds ...201222408253
voluntary ingestion of antiparasitic drugs emulsified in honey represents an alternative to gavage in mice.the oral route is the most frequently used method of drug intake in humans. oral administration of drugs to laboratory animals such as mice typically is achieved through gavage, in which a feeding needle is introduced into the esophagus and the drug is delivered directly into the stomach. this method requires technical skill, is stressful for animals, and introduces risk of injury, pain and morbidity. here we investigated another method of drug administration. the benzimidazole derivative albend ...201222776122
genome sequence of the highly efficient arsenite-oxidizing bacterium achromobacter arsenitoxydans sy8.we report the draft genome sequence of achromobacter arsenitoxydans sy8, the first reported arsenite-oxidizing bacterium belonging to the genus achromobacter and containing a genomic arsenic island, an intact type iii secretion system, and multiple metal(loid) transporters. the genome may be helpful to explore the mechanisms intertwining metal(loid) resistance and pathogenicity.201222328747
out-patient antimicrobial drug use in dogs and cats for new disease events from community companion animal practices in ontario.this study investigated oral and parenteral antimicrobial use in dogs and cats, and evaluated antimicrobial use in feline upper respiratory tract disease (furtd), feline lower urinary tract disease (flutd), and canine infectious tracheobronchitis. study journals (n = 1807) were submitted by 84 veterinarians. sixty-five percent of the antimicrobials prescribed in dogs and 67% in cats were β-lactams. most frequently prescribed in dogs were cephalexin (33%) and amoxicillin-clavulanic acid (16%), an ...201222942447
prevalence and genetic characterization of pertactin-deficient bordetella pertussis in japan.the adhesin pertactin (prn) is one of the major virulence factors of bordetella pertussis, the etiological agent of whooping cough. however, a significant prevalence of prn-deficient (prn(-)) b. pertussis was observed in japan. the prn(-) isolate was first discovered in 1997, and 33 (27%) prn(-) isolates were identified among 121 b. pertussis isolates collected from 1990 to 2009. sequence analysis revealed that all the prn(-) isolates harbor exclusively the vaccine-type prn1 allele and that loss ...201222348138
global effects of catecholamines on actinobacillus pleuropneumoniae gene expression.bacteria can use mammalian hormones to modulate pathogenic processes that play essential roles in disease development. actinobacillus pleuropneumoniae is an important porcine respiratory pathogen causing great economic losses in the pig industry globally. stress is known to contribute to the outcome of a. pleuropneumoniae infection. to test whether a. pleuropneumoniae could respond to stress hormone catecholamines, gene expression profiles after epinephrine (epi) and norepinephrine (ne) treatmen ...201222347439
effect of chemokine receptor cx3cr1 deficiency in a murine model of respiratory syncytial virus infection.respiratory syncytial virus (rsv) is the most common cause of serious lower respiratory illness in infants and young children worldwide, making it a high priority for development of strategies for prevention and treatment. rsv can cause repeat infections throughout life, with serious complications in elderly and immunocompromised patients. previous studies indicate that the rsv g protein binds through a cx3c chemokine motif to the host chemokine receptor, cx3cr1, and modulates the inflammatory i ...201222330646
self-made phage libraries with heterologous inserts in the mtd of bordetella bronchiseptica.phage display libraries are widely used as tools for identifying, dissecting and optimizing ligands. development of a simple method to access greater library diversities could expedite and expand the technique. this paper reports progress toward harnessing the naturally occurring diversity generating retroelement used by bordetella bronchiseptica bacteriophage to alter its tail-fiber protein. mutagenesis and testing identified four sites amenable to the insertion of <19-residue heterologous pept ...201222286238
network model of immune responses reveals key effectors to single and co-infection dynamics by a respiratory bacterium and a gastrointestinal helminth.co-infections alter the host immune response but how the systemic and local processes at the site of infection interact is still unclear. the majority of studies on co-infections concentrate on one of the infecting species, an immune function or group of cells and often focus on the initial phase of the infection. here, we used a combination of experiments and mathematical modelling to investigate the network of immune responses against single and co-infections with the respiratory bacterium bor ...201222253585
oral gavage in rats: animal welfare evaluation.the effect of chronic daily orogastric gavage with water (5 ml/kg) on behavior and physiology was evaluated in male sprague-dawley rats. treatment groups included: unmanipulated control, restraint control, dry gavage, and gavage, with all rats singly housed (n = 9 or 10 per group). in addition, a group of pair-housed rats (n = 18) was included to determine whether social housing affected response to gavage. weekly body weights and food consumption were recorded as well as use of a nylon chew toy ...201222330864
vaccine potential of an attenuated pasteurella multocida that expresses only the n-terminal truncated fragment of p. multocida toxin in pigs.previously we described the development of an attenuated pasteurella multocida mutant that expresses only the n-terminal truncated fragment of p. multocida toxin (n-pmt) and its protective effects in a mouse model. this paper details our evaluation of the vaccine potential of this mutant strain in pigs. pigs vaccinated with the mutant showed significantly higher rates of antibody induction and lower nasal conchal (turbinate) scores for atrophic rhinitis than controls, which suggests that this mu ...201222754098
immuno-epidemiology of chronic bacterial and helminth co-infections: observations from the field and evidence from the laboratory.co-infections can alter the host immune responses and modify the intensity and dynamics of concurrent parasitic species. the extent of this effect depends on the properties of the system and the mechanisms of host-parasite and parasite-parasite interactions. we examined the immuno-epidemiology of a chronic co-infection to reveal the immune mediated relationships between two parasites colonising independent organs, and the within-host molecular processes influencing the dynamics of infection at t ...201222584129
recurrent respiratory infection caused by bordetella bronchiseptica in an immunocompetent infant.bordetella bronchiseptica rarely infects immunocompetent humans. we report an unusual case of recurrent pertussis-like syndrome caused by b. bronchiseptica in a 7-month-old immunocompetent boy. molecular analysis demonstrated that the isolates from the child and mother were identical.201222572751
btc22 chaperone is required for secretion and stability of the type iii secreted protein bsp22 in bordetella bronchiseptica.the type iii secretion system (t3ss) is a sophisticated protein secretion machinery that delivers bacterial virulence proteins into host cells. a needle-tip protein, bsp22 , is one of the secreted substrates of the t3ss and plays an essential role in the full function of the t3ss in bordetella bronchiseptica. in this study, we found that bb1618 functions as a chaperone for bsp22 . the deletion of bb1618 resulted in a dramatic impairment of bsp22 secretion into the culture supernatants and bsp22 ...201222458424
swine atrophic rhinitis caused by pasteurella multocida toxin and bordetella dermonecrotic toxin.atrophic rhinitis is a widespread and economically important swine disease caused by pasteurella multocida and bordetella bronchiseptica. the disease is characterized by atrophy of the nasal turbinate bones, which results in a shortened and deformed snout in severe cases. p. multocida toxin and b. bronchiseptica dermonecrotic toxin have been considered to independently or cooperatively disturb the osteogenesis of the turbinate bone by inhibiting osteoblastic differentiation and/or stimulating bo ...201222411430
iron starvation regulates the type iii secretion system in bordetella bronchiseptica.the type iii secretion system (t3ss) plays a key role in the exertion of full virulence by bordetella bronchiseptica. however, little is known about the environmental stimuli that induce expression of t3ss genes. here, it is reported that iron starvation is a signal for t3ss gene expression in b. bronchiseptica. it was found that, when b. bronchiseptica is cultured under iron-depleted conditions, secretion of type iii secreted proteins is greater than that in bacteria grown under iron-replete co ...201222376189
structure and catalytic mechanism of nicotinate (vitamin b3) degradative enzyme maleamate amidohydrolase from bordetella bronchiseptica rb50.the penultimate reaction in the oxidative degradation of nicotinate (vitamin b(3)) to fumarate in several species of aerobic bacteria is the hydrolytic deamination of maleamate to maleate, catalyzed by maleamate amidohydrolase (nicf). although it has been considered a model system for bacterial degradation of n-heterocyclic compounds, only recently have gene clusters that encode the enzymes of this catabolic pathway been identified to allow detailed investigations concerning the structural basis ...201222214383
[bacterial susceptibility testings of the lower airways of diseased dogs].in this retrospective study over 5 years the bacterial flora of the deep airways of diseased dogs was sampled using bronchioalveolar lavage and its in-vitro susceptibility to numerous antimicrobial agents was analysed.201223076014
spontaneous bacterial peritonitis and pneumonia caused by bordetella bronchiseptica.bordetella bronchiseptica is a rare cause of invasive human infection. the most common infection in humans is the respiratory tract infection and it is usually associated with immunosuppression, particularly acquired immunodeficiency syndrome (aids). we report a case of a pneumonia and peritonitis in a 42-year-old female with alcoholic liver disease. the patient died despite treatment with antibiotics. this case illustrates the potential virulence of b. bronchiseptica in susceptible patients and ...201222842947
dual mechanism of protection by live attenuated bordetella pertussis bpze1 against bordetella bronchiseptica in mice.bordetella bronchiseptica, a gram-negative bacterium, causes chronic respiratory tract infections in a wide variety of mammalian hosts, including man, and no human vaccine is currently available. acellular pertussis vaccines protect poorly against b. bronchiseptica, although they contain cross-reactive antigens. we have recently developed bordetella pertussis bpze1, a novel, live attenuated pertussis vaccine, currently completing phase i clinical trials in humans, and found that it protects agai ...201222814407
comparison of the efficacy of amoxicillin-clavulanic acid, cefovecin, and doxycycline in the treatment of upper respiratory tract disease in cats housed in an animal shelter.to compare efficacy of amoxicillin-clavulanic acid, cefovecin, and doxycycline in shelter-housed cats with clinical signs of upper respiratory tract disease (urtd).201222765368
the limitations of draft assemblies for understanding prokaryotic adaptation and evolution.the de novo assembly of next generation sequencing data is a daunting task made more difficult by the presence of genomic repeats or transposable elements, resulting in an increasing number of genomes designated as completed draft assemblies. we created and assembled idealized sequence data sets for cupriavidus metallidurans ch34, caulobacter sp. k31, gramella forsetii kt0803, rhodobacter sphaeroides 2.4.1 and bordetella bronchiseptica rb50. in addition to confirming the role of transposable ele ...201222750556
development and characterization of attenuated metabolic mutants of bordetella bronchiseptica for applications in vaccinology.bordetella bronchiseptica is an important pathogen causing a number of veterinary respiratory syndromes in agriculturally important and food-producing confinement-reared animals, resulting in great economic losses annually amounting to billions of euros worldwide. currently available live vaccines are incompletely satisfactory in terms of efficacy and safety. an efficient vaccine for livestock animals would allow reducing the application of antibiotics, thereby preventing the massive release of ...201322676396
susceptibility of canine and feline bacterial pathogens to pradofloxacin and comparison with other fluoroquinolones approved for companion animals.in this study, 908 bacterial pathogens from defined infections of dogs and cats were tested for their susceptibility to the novel fluoroquinolone pradofloxacin, which was approved in 2011 for use in cats and dogs. most of the bacteria tested (staphylococcus aureus, staphylococcus pseudintermedius, escherichia coli, β-haemolytic streptococci, pasteurella multocida and bordetella bronchiseptica) exhibited low pradofloxacin mic(90) values of ≤ 0.25 μg/ml. solely proteus spp. and pseudomonas aerugin ...201322939523
aroa deleted bordetella bronchiseptica inspiring robust mucosal immune response and provide full protection against intranasal challenge.bordetella bronchiseptica is a gram-negative respiratory pathogen responsible for atrophic rhinitis and bronchopneumonia in swine. several vaccines aimed at preventing b. bronchiseptica have been used, but a safe and efficient live vaccine for use in piglets remains elusive. in this study, we constructed an aroa-deleted b. bronchiseptica strain (qh0814) and evaluated its safety and protective efficiency in piglets. lung lesion scores in qh0814-immunized piglets post-challenge were significantly ...201322892249
epidemiology of whooping cough & typing of bordetella pertussis.bordetella pertussis is a gram-negative human-restricted bacterium that evolved from the broad-range mammalian pathogen, bordetella bronchiseptica. it causes whooping cough or pertussis in humans, which is the most prevalent vaccine-preventable disease worldwide. the introduction of the pertussis whole-cell vaccination for young children, followed by the introduction of the pertussis acellular vaccination (along with booster vaccination) for older age groups, has affected the bacterial populatio ...201324199799
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