Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| eradication of intracellular francisella tularensis in thp-1 human macrophages with a novel autophagy inducing agent. | autophagy has been shown recently to play an important role in the intracellular survival of several pathogenic bacteria. in this study, we investigated the effect of a novel small-molecule autophagy-inducing agent, ar-12, on the survival of francisella tularensis, the causative bacterium of tularemia in humans and a potential bioterrorism agent, in macrophages. | 2009 | 20003180 |
| interleukin-17 kick-starts t helper 1 cell differentiation. | in this issue of immunity, lin et al. (2009) implicate interleukin-17 in the regulation of t helper 1 (th1) cell immunity against francisella tularensis. these findings add a unique twist to the cytokine regulation of t cell differentiation and function. | 2009 | 19932069 |
| tlr-dependent control of francisella tularensis infection and host inflammatory responses. | francisella tularensis is the causative agent of tularemia and is classified as a category a select agent. recent studies have implicated tlr2 as a critical element in the host protective response to f. tularensis infection, but questions remain about whether tlr2 signaling dominates the response in all circumstances and with all species of francisella and whether f. tularensis pamps are predominantly recognized by tlr2/tlr1 or tlr2/tlr6. to address these questions, we have explored the role of ... | 2009 | 19936231 |
| akt and ship modulate francisella escape from the phagosome and induction of the fas-mediated death pathway. | francisella tularensis infects macrophages and escapes phago-lysosomal fusion to replicate within the host cytosol, resulting in host cell apoptosis. here we show that the fas-mediated death pathway is activated in infected cells and correlates with escape of the bacterium from the phagosome and the bacterial burden. our studies also demonstrate that constitutive activation of akt, or deletion of ship, promotes phago-lysosomal fusion and limits bacterial burden in the host cytosol, and the subse ... | 2009 | 19936232 |
| working toward the future: insights into francisella tularensis pathogenesis and vaccine development. | francisella tularensis is a facultative intracellular gram-negative pathogen and the etiological agent of the zoonotic disease tularemia. recent advances in the field of francisella genetics have led to a rapid increase in both the generation and subsequent characterization of mutant strains exhibiting altered growth and/or virulence characteristics within various model systems of infection. in this review, we summarize the major properties of several francisella species, including f. tularensis ... | 2009 | 19946137 |
| francisella tularensis subsp. novicida isolated from a human in arizona. | francisella tularensis is the etiologic agent of tularemia and is classified as a select agent by the centers for disease control and prevention. currently four known subspecies of f. tularensis that differ in virulence and geographical distribution are recognized:tularensis (type a), holarctica (type b), mediasiatica, and novicida. because of the select agent status and differences in virulence and geographical location, the molecular analysis of any clinical case of tularemia is of particular ... | 2009 | 19895698 |
| possible interaction between a rodenticide treatment and a pathogen in common vole (microtus arvalis) during a population peak. | a common vole (microtus arvalis) population peak in northern spain in 2007 was treated with large scale application of chlorophacinone, an anticoagulant rodenticide of the indandione family. voles found dead and trapped alive were collected in treated and untreated areas. residues of chlorophacinone were analyzed in liver of voles by hplc-uv. also, the presence of the pathogen francisella tularensis was analyzed by pcr in samples of vole spleen. chlorophacinone (82-3800 ng/g; wet weight liver) w ... | 2009 | 19863999 |
| small molecule control of virulence gene expression in francisella tularensis. | in francisella tularensis, the sspa protein family members mgla and sspa form a complex that associates with rna polymerase (rnap) to positively control the expression of virulence genes critical for the intramacrophage growth and survival of the organism. although the association of the mgla-sspa complex with rnap is evidently central to its role in controlling gene expression, the molecular details of how mgla and sspa exert their effects are not known. here we show that in the live vaccine st ... | 2009 | 19876386 |
| francisella virulence: significant advances, ongoing challenges and unmet needs. | francisella tularensis, the causative agent of tularemia, is an organism of concern as a potential biowarfare agent. progress towards understanding the molecular basis of pathogenicity has been hampered by a lack of tools with which to manipulate the pathogen. however, the availability of genome sequence data for a range of strains and the development of a range of plasmids and mutagenesis protocols for use in francisella has resulted in a huge advance in understanding. no licensed vaccine is ye ... | 2009 | 19863250 |
| interleukin-17 is required for t helper 1 cell immunity and host resistance to the intracellular pathogen francisella tularensis. | the importance of t helper type 1 (th1) cell immunity in host resistance to the intracellular bacterium francisella tularensis is well established. however, the relative roles of interleukin (il)-12-th1 and il-23-th17 cell responses in immunity to f. tularensis have not been studied. the il-23-th17 cell pathway is critical for protective immunity against extracellular bacterial infections. in contrast, the il-23-th17 cell pathway is dispensable for protection against intracellular pathogens such ... | 2009 | 19853481 |
| [identification and characterization of the francisella sp. strain 08hl01032 isolated in air condition systems]. | to identify and characterize the strain 08h101032 was isolated from air condition systems in the routine investigations of legionella in guangzhou, china, in 2008. | 2009 | 19835160 |
| effect of dehydrated storage on the survival of francisella tularensis in infant formula. | francisella tularensis is a gram-negative bacterium that can cause gastrointestinal or oropharyngeal tularemia in humans from ingestion of contaminated food or water. despite the potential for accidental or intentional contamination of foods with f. tularensis, there are few studies on the long-term survivability of this organism in food matrices. infant formula has previously been implicated as a vehicle for the transmission of a variety of bacterial pathogens in infants. in this study, we inve ... | 2009 | 19835784 |
| crystal structures of the histidine acid phosphatase from francisella tularensis provide insight into substrate recognition. | histidine acid phosphatases catalyze the transfer of a phosphoryl group from phosphomonoesters to water at acidic ph using an active-site histidine. the histidine acid phosphatase from the category a pathogen francisella tularensis (fthap) has been implicated in intramacrophage survival and virulence, motivating interest in understanding the structure and mechanism of this enzyme. here, we report a structure-based study of ligand recognition by fthap. the 1.70-a-resolution structure of fthap com ... | 2009 | 19836403 |
| francisella tularensis vaccines. | francisella tularensis has attracted attention historically as a biological weapon, due to its high infectivity in aerosols, and the severity of disease in humans. there is no licensed vaccine currently available, although an attenuated live vaccine strain (lvs) was identified in the middle of the last century and has been successfully used to protect humans. efforts are underway to determine the basis of attenuation of lvs, and to understand the immunity required for protection. alternative app ... | 2009 | 19837286 |
| water-borne outbreak of oropharyngeal and glandular tularemia in georgia: investigation and follow-up. | in november 2006, an outbreak of waterborne tularemia occurred in an eastern region in the republic of georgia. outbreak investigation revealed 26 cases: 21 oropharyngeal and 5 glandular tularemia cases. | 2009 | 19826763 |
| bacillus anthracis, francisella tularensis and yersinia pestis. the most important bacterial warfare agents - review. | there are three most important bacterial causative agents of serious infections that could be misused for warfare purposes: bacillus anthracis (the causative agent of anthrax) is the most frequently mentioned one; however, fracisella tularensis (causing tularemia) and yersinia pestis (the causative agent of plague) are further bacterial agents enlisted by centers for disease control and prevention into the category a of potential biological weapons. this review intends to summarize basic informa ... | 2009 | 19826916 |
| [the time course of changes in cell immunological parameters during administration of live dry plague vaccine]. | the study of the time course of changes in cell immunological parameters by a magnetic separation technique in human beings during the administration of plague vaccine in relation to the immunological load revealed the higher blood levels of all t lymphocyte subpopulations on day 14 after vaccination. these changes are most typical of a primary vaccinated cohort. the increased frequency of plague vaccine administration and multiple immunizations with live plague, anthrax, and tularemia vaccines ... | 2009 | 19827193 |
| francisella tularensis novicida proteomic and transcriptomic data integration and annotation based on semantic web technologies. | this paper summarises the lessons and experiences gained from a case study of the application of semantic web technologies to the integration of data from the bacterial species francisella tularensis novicida (fn). fn data sources are disparate and heterogeneous, as multiple laboratories across the world, using multiple technologies, perform experiments to understand the mechanism of virulence. it is hard to integrate these data sources in a flexible manner that allows new experimental data to b ... | 2009 | 19796400 |
| proteome analysis of an attenuated francisella tularensis dsba mutant: identification of potential dsba substrate proteins. | francisella tularensis (f. tularensis) is highly infectious for humans via aerosol route and untreated infections with the highly virulent subsp. tularensis can be fatal. our knowledge regarding key virulence determinants has increased recently but is still somewhat limited. surface proteins are potential virulence factors and therapeutic targets, and in this study, we decided to target three genes encoding putative membrane lipoproteins in f. tularensis lvs. one of the genes encoded a protein w ... | 2009 | 19799467 |
| generation of heterogeneous memory t cells by live attenuated tularemia vaccine in humans. | there is very limited evidence concerning the phenotype, function, and homing characteristics of memory t (t(m)) cells elicited by vaccination against intracellular bacteria in humans. here we studied t(m) subsets elicited by exposure to francisella tularensis in humans as a model of immunity to intracellular bacteria. to this end, t(m) cells were evaluated in two groups: (1) subjects immunized with live attenuated tularemia vaccine by skin scarification and (2) tularemia naturally infected subj ... | 2009 | 19799845 |
| [severe tularaemia mimicking glandular tuberculosis during adalimumab therapy]. | tularaemia is an anthropozoonosis, transmitted by small mammals (hares) and arthropods (ticks, horseflies). the causative agent is francisella tularensis, a facultatively intracellular gram-negative bacillus. we report a case of tularaemia in its ulceroglandular form occurring during methotrexate and adalimumab treatment (humira) for rheumatoid arthritis. | 2009 | 19801257 |
| programmed cell death and the pathogenesis of tissue injury induced by type a francisella tularensis. | francisella tularensis is a highly virulent bacterial species that causes various forms of tularemia in humans. the urgency in understanding the pathogenesis of these diseases has stimulated unprecedented interest in this bacterial species over the past few years. recent findings underscore a number of important distinctions between the francisella ssp. and emphasize the importance of using type a f. tularensis strains when characterizing pathophysiological responses that are relevant to the let ... | 2009 | 19811540 |
| whole genome single nucleotide polymorphism based phylogeny of francisella tularensis and its application to the development of a strain typing assay. | a low genetic diversity in francisella tularensis has been documented. current dna based genotyping methods for typing f. tularensis offer a limited and varying degree of subspecies, clade and strain level discrimination power. whole genome sequencing is the most accurate and reliable method to identify, type and determine phylogenetic relationships among strains of a species. however, lower cost typing schemes are necessary in order to enable typing of hundreds or even thousands of isolates. | 2009 | 19811647 |
| [a patient with a fever and an eschar caused by tularemia]. | a 38-year-old man presented at the first-aid department complaining of fever, general malaise and a painful left groin. the complaints had started shortly after an active holiday in finland. physical examination showed enlarged left sided inguinal lymph nodes and a marked eschar on the left lower leg. in terms of differential diagnosis a rickettsia or a tularemia infection were considered. the pathogen for tularemia, francisella tularensis subspecies holarctica, was isolated in wound discharge f ... | 2009 | 19818182 |
| francisella tularensis type a strains cause the rapid encystment of acanthamoeba castellanii and survive in amoebal cysts for three weeks postinfection. | francisella tularensis, the causative agent of the zoonotic disease tularemia, has recently gained increased attention due to the emergence of tularemia in geographical areas where the disease has been previously unknown and to the organism's potential as a bioterrorism agent. although f. tularensis has an extremely broad host range, the bacterial reservoir in nature has not been conclusively identified. in this study, the ability of virulent f. tularensis strains to survive and replicate in the ... | 2009 | 19820161 |
| humans and evolutionary and ecological forces shaped the phylogeography of recently emerged diseases. | the development of human civilizations and global commerce has led to the emergence and worldwide circulation of many infectious diseases. anthrax, plague and tularaemia are three zoonotic diseases that have been intensely studied through genome characterization of the causative species and phylogeographical analyses. a few highly fit genotypes in each species represent the causative agents for most of the observed disease cases. together, mutational and selective forces create highly adapted pa ... | 2009 | 19820723 |
| environmental and intracellular regulation of francisella tularensis ripa. | francisella tularensis is a highly virulent, facultative intracellular pathogen and the etiologic agent of the zoonotic disease tularemia. ripa is a cytoplasmic membrane protein that is conserved among francisella species and is required for intracellular growth. f. tularensis ripa deletion mutants escape the phagosome of infected cells, but unlike wild type organisms fail to replicate in the host cell cytoplasm. | 2009 | 19821974 |
| francisella asiatica sp. nov. isolated from farmed tilapia (oreochromis sp.) and elevation of francisella philomiragia subsp. noatunensis to species rank as francisella noatunensis comb. nov., sp. nov. | bacterial isolates from diseased farmed tilapia (oreochromis sp.) from costa rica (pq 1104), atlantic salmon (salmo salar) from chile (pq 1106) and three-line grunt (parapristipoma trilineatum) from japan (ehime-1) were characterized by phenotypic and molecular taxonomic methods. these isolates were gram-negative, oxidase negative, non-motile, strictly aerobic cocco-bacilli, produced h2s from cysteine supplemented media, which is phenotypically consistent with the genus francisella. comparison o ... | 2009 | 19783606 |
| [prevalence of epidemic outbreak of tularemia in the hospital universitario río hortega (spain) in the year 2007]. | this present research study presents the analytic results of an outbreak of tularemia (francisella tularensis) that occurred in the northwest areas of castilla y león in northern spain in late june 2007. | 2009 | 19709538 |
| [tularemia as a pediatric problem]. | the diagnosis of tularemia is based on the clinical picture, and epidemics are brief and local. in children, recognition of tularaemia may be challenging, as an inflamed mosquito bite mark may be covered under the hair, and lymph node enlargement is associated with other febrile diseases as well. half of the children have vesicopapular skin changes. fluoroqinolones and aminoglycosides area effective against francisella tularensis in vitro, and the efficacy of treatment seems to be the better the ... | 2009 | 19711573 |
| improved shuttle vectors for francisella tularensis genetics. | we previously described the construction and characterization of escherichia coli-francisella tularensis shuttle vectors, derived from the cryptic francisella plasmid pfnl10, for the genetic manipulation of f. tularensis ssp. tularensis. we now report further characterization of the biology of these shuttle vectors and the development of a new generation of francisella plasmids. we show that the addition of orf3 from pfnl10 can convert an unstable shuttle vector into a stable one, and that this ... | 2009 | 19067747 |
| characterization and genotyping of strains of francisella tularensis isolated in bulgaria. | a tularaemia focus was detected in 1998 in bulgaria, in an area where tularaemia had never been reported. the properties of francisella tularensis subsp. holarctica strains isolated from 1998 to 2005 were studied. the strains showed heterogeneity, based on acid production from glycerol and erythromycin susceptibility. genotyping by analysis of seven loci containing variable-number tandem repeats showed four genotypes among eight strains. | 2009 | 19074656 |
| an outbreak of oropharyngeal tularaemia linked to natural spring water. | a tularaemia outbreak was investigated involving 188 suspected cases in the kocaeli region of turkey between december 2004 and april 2005. a case-control study comprising 135 laboratory-confirmed cases and 55 controls was undertaken to identify risk factors for the development of the outbreak and to evaluate laboratory diagnostic methods. tularaemia was confirmed by a microagglutination test (mat) titre of >or=1 : 160 in 90 of the patients. in mat-negative sera, 23/44 (52 %) were positive by eli ... | 2009 | 19074661 |
| editorial: proinflammatory cytokines in pneumonic tularemia: too much too late? | 2009 | 19720615 | |
| substituted diphenyl ethers as a broad-spectrum platform for the development of chemotherapeutics for the treatment of tularaemia. | the national institute of allergy and infectious disease classifies francisella tularensis as a category a priority pathogen. despite the availability of drugs for treating tularaemia, the mortality in naturally acquired cases can still approach 30%. in addition, the usefulness of existing drugs for treatment in response to exposure or for prophylaxis is limited because of toxicity and delivery concerns. the aim of this study was to assess the efficacy of the lead alkyl-substituted diphenyl ethe ... | 2009 | 19734171 |
| innate immune response during yersinia infection: critical modulation of cell death mechanisms through phagocyte activation. | yersinia pestis, the etiological agent of plague, is one of the most deadly pathogens on our planet. this organism shares important attributes with its ancestral progenitor, yersinia pseudotuberculosis, including a 70-kb virulence plasmid, lymphotropism during growth in the mammalian host, and killing of host macrophages. infections with both organisms are biphasic, where bacterial replication occurs initially with little inflammation, followed by phagocyte influx, inflammatory cytokine producti ... | 2009 | 19734471 |
| global transcriptional response to spermine, a component of the intramacrophage environment, reveals regulation of francisella gene expression through insertion sequence elements. | tularemia is caused by the category a biodefense agent francisella tularensis. this bacterium is associated with diverse environments and a plethora of arthropod and mammalian hosts. how f. tularensis adapts to these different conditions, particularly the eukaryotic intracellular environment in which it replicates, is poorly understood. here, we demonstrate that the polyamines spermine and spermidine are environmental signals that alter bacterial stimulation of host cells. genomewide analysis sh ... | 2009 | 19749055 |
| a novel role for plasmin-mediated degradation of opsonizing antibody in the evasion of host immunity by virulent, but not attenuated, francisella tularensis. | opsonization by abs represents a critical component of the host immune response against many pathogens. the mechanisms by which virulent microbes evade this protective response are not completely understood. in disease mediated by francisella tularensis, ab can effectively protect against infections with attenuated strains, for example, lvs, but not virulent strains such as schus4. thus, it is likely that schus4 has mechanisms, which are not present in lvs, that allow evasion of opsonization by ... | 2009 | 19752236 |
| complete genome sequence of francisella tularensis subspecies holarctica ftnf002-00. | francisella tularensis subspecies holarctica ftnf002-00 strain was originally obtained from the first known clinical case of bacteremic f. tularensis pneumonia in southern europe isolated from an immunocompetent individual. the ftnf002-00 complete genome contains the rd(23) deletion and represents a type strain for a clonal population from the first epidemic tularemia outbreak in spain between 1997-1998. here, we present the complete sequence analysis of the ftnf002-00 genome. the complete genom ... | 2009 | 19756146 |
| differentiation of gram-negative bacterial aerosol exposure using detected markers in bronchial-alveolar lavage fluid. | the identification of biosignatures of aerosol exposure to pathogens has the potential to provide useful diagnostic information. in particular, markers of exposure to different types of respiratory pathogens may yield diverse sets of markers that can be used to differentiate exposure. we examine a mouse model of aerosol exposure to known gram negative bacterial pathogens, francisella tularensis novicida and pseudomonas aeruginosa. mice were subjected to either a pathogen or control exposure and ... | 2009 | 19756149 |
| rela regulates virulence and intracellular survival of francisella novicida. | analysis of the genome of francisella tularensis has revealed few regulatory systems, and how the organism adapts to conditions in different niches is poorly understood. the stringent response is a global stress response mediated by (p)ppgpp. the enzyme rela has been shown to be involved in generation of this signal molecule in a range of bacterial species. we investigated the effect of inactivation of the rela gene in francisella by generating a mutant in francisella novicida. under amino acid ... | 2009 | 19762448 |
| identification of francisella tularensis live vaccine strain cuzn superoxide dismutase as critical for resistance to extracellularly generated reactive oxygen species. | francisella tularensis is an intracellular pathogen whose survival is in part dependent on its ability to resist the microbicidal activity of host-generated reactive oxygen species (ros) and reactive nitrogen species (rns). in numerous bacterial pathogens, cuzn-containing superoxide dismutases (sodc) are important virulence factors, localizing to the periplasm to offer protection from host-derived superoxide radicals (o(2)(-)). in the present study, mutants of f. tularensis live vaccine strain ( ... | 2009 | 19684141 |
| real-time pcr strategy and detection of bacterial agents of lymphadenitis. | the aim of this study was to compare 16 s rrna gene amplification and sequencing with a systematic real-time pcr assay screening strategy that includes all common known pathogens recovered from lymph node biopsy specimens. lymph node biopsy samples sent to our laboratory from january 2007 to december 2008 were tested in the study. lymph nodes were screened for the presence of any bacteria by pcr amplification and sequencing targeting the 16 s rrna gene and also by a specific real-time pcr strate ... | 2009 | 19685089 |
| [tularemia]. | tularemia is a zoonotic disease caused by francisella tularensis. the etiological agent is transmitted to man by direct contact with infected animals, air, water or contaminated food, or through hematophagous vectors. in portugal, in 1998, after an outbreak in spain, the direcção geral de saúde issued a warning, alerting the clinicians to the possibility of the disease spreading throughout the national territory. in this work, an epidemiological review of tularemia is made in order to contribute ... | 2009 | 19686629 |
| francisella tularensis induces ubiquitin-dependent major histocompatibility complex class ii degradation in activated macrophages. | the intracellular bacterium francisella tularensis survives and replicates within macrophages, ultimately killing the host cell. resolution of infection requires the development of adaptive immunity through presentation of f. tularensis antigens to cd4+ and cd8+ t cells. we have previously established that f. tularensis induces macrophage prostaglandin e2 (pge2) production, leading to skewed t-cell responses. pge2 can also downregulate macrophage major histocompatibility complex (mhc) class ii e ... | 2009 | 19703975 |
| francisella tularensis induces extensive caspase-3 activation and apoptotic cell death in the tissues of infected mice. | although francisella tularensis subsp. tularensis is known to cause extensive tissue necrosis, the pathogenesis of tissue injury has not been elucidated. to characterize cell death in tularemia, c57bl/6 mice were challenged by the intranasal route with type a f. tularensis, and the pathological changes in infected tissues were characterized over the next 4 days. at 3 days postinfection, well-organized inflammatory infiltrates developed in the spleen and liver following the spread of infection fr ... | 2009 | 19703976 |
| cgug: in silico proteome and genome parsing tool for the determination of "core" and unique genes in the analysis of genomes up to ca. 1.9 mb. | viruses and small-genome bacteria (~2 megabases and smaller) comprise a considerable population in the biosphere and are of interest to many researchers. these genomes are now sequenced at an unprecedented rate and require complementary computational tools to analyze. "coregenesuniquegenes" (cgug) is an in silico genome data mining tool that determines a "core" set of genes from two to five organisms with genomes in this size range. core and unique genes may reflect similar niches and needs, and ... | 2009 | 19706165 |
| specific recognition of the major capsid protein of acanthamoeba polyphaga mimivirus by sera of patients infected by francisella tularensis. | francisella tularensis, a gram-negative cocobacillus responsible for tularemia, especially severe pneumonia, is a facultative intracellular bacterium classified as a biological agent of category a. acanthamoeba polyphaga mimivirus (apm) is a recently discovered giant virus suspected to be an agent of both community- and hospital-acquired pneumonia. during specificity testing of antibody to apm detection, it was observed that nearly all patients infected by f. tularensis had elevated antibody tit ... | 2009 | 19538509 |
| [prolonged course of tick-borne ulceroglandular tularemia in a 20-year-old patient in germany--case report and review of the literature]. | a 20-year-old female patient presented with painful axillary lymphadenopathy. she reported a tick bite five months ago in her right hand followed by fever, chills and regional lymphadenopathy. empiric antibiotic treatment with doxycyclin and ciprofloxacin had led to defervescence but no change in painful lymph node swellings. surgical removal of a cubital lymph node had already been performed three months after the tick bite. | 2009 | 19551605 |
| tick-borne zoonotic bacteria in ticks collected from central spain. | the prevalence of tick-borne and related bacteria infecting adult ticks in central spain was assessed by molecular methods. six areas were sampled monthly during a 2-year longitudinal study. a total of 1,038 questing and 442 feeding ticks, belonging to eight different species, were tested. the most abundant species were hyalomma lusitanicum (54% of captures), followed by dermacentor marginatus (23%) and rhipicephalus sanguineus (10%). four human pathogens, including seven rickettsia species, ana ... | 2009 | 19556569 |
| tularemia induces different biochemical responses in balb/c mice and common voles. | both balb/c mice and common voles (microtus arvalis) are considered highly susceptible to tularemia. however, the common vole is reported to harbour francisella tularensis in european habitats as well as to survive longer with chronic shedding of the bacterium. the purpose of the present study was to compare the response of these two rodents to a wild francisella tularensis subsp. holarctica strain infection. | 2009 | 19558687 |
| safety, reactogenicity and immunogenicity of francisella tularensis live vaccine strain in humans. | we evaluated the safety, reactogenicity and immunogenicity of escalating doses of a new francisella tularensis live vaccine strain (lvs) lot by scarification (scar) or subcutaneously (sq) in humans. subjects (n=10/group) received one dose of lvs via scar at 10(5),10(7) or 10(9)cfu/ml or sq at 10(2), 10(3),10(4) or 10(5)cfu/ml; 14 subjects received placebo. all doses/routes were well tolerated. when compared to placebo, vaccination with 10(7) scar and 10(9) scar resulted in significantly higher s ... | 2009 | 19567246 |
| tularemia type a in captive bornean orangutans (pongo pygmaeus pygmaeus). | in 2003, tularemia was suspected to be the cause of severe illness in two orangutans (pongo pygmaeus pygmaeus) and the cause of death in a third orangutan at an urban zoo. the two sick orangutans were treated two times under chemical immobilization with i.v. doxycycline, fluids, and antipyretic drugs, followed by a sustained course of oral doxycycline. the rest of the orangutan group was treated prophylactically with oral doxycycline. postmortem diagnosis was obtained via immunohistochemistry an ... | 2009 | 19569471 |
| [experimental verification of a model of complement-dependent immune lysis of liposomes]. | the quantitative dependences of the immune complement-dependent lysis of a monodisperse suspension of 200-nm liposomes whose membrane was sensitized by monovalent hapten (2,4-dnp-epsilon-caproyl-dppe) or a polyvalent antigen (lps from f. tularensis) on the initial concentration of specific antibodies (igg) to hapten and the antigen have been investigated. the quantity of antibodies binding sites on the surface of liposome was evaluated. the difference between the complement-dependent immune lysi ... | 2009 | 19569506 |
| familial tularaemia. | tularaemia is a zoonotic disease caused by francisella tularensis . in this report, we have presented an early stage case of tularemia with fever and pharyngitis and two cases from the same non-endemic region with typical lymphadenitis. all three patients were treated with non-specific medications in healthcare centres, the treatment being directed towards symptoms resembling those of upper respiratory tract infections. however, there was no regression in their complaints. because the first case ... | 2009 | 19584516 |
| comparative antimicrobial activity of granulysin against bacterial biothreat agents. | granulysin is a cationic protein produced by human t cells and natural killer cells that can kill bacterial pathogens through disruption of microbial membrane integrity. herein we demonstrate antimicrobial activity of the granulysin peptide derived from the active site against bacillus anthracis, yersinia pestis, francisella tularensis, and burkholderia mallei, and show pathogen-specific differences in granulysin peptide effects. the susceptibility of y. pestis to granulysin is temperature depen ... | 2009 | 19587798 |
| tularemia - missouri, 2000-2007. | tularemia is an uncommon but potentially fatal zoonotic disease caused by the gram-negative coccobacillus francisella tularensis. approximately 40% of all tularemia cases reported to cdc each year occur in arkansas, oklahoma, and missouri. to define the epidemiologic and clinical features of tularemia in missouri, the missouri department of health and senior services (mdhss) analyzed surveillance data and conducted a retrospective clinical chart review of cases that occurred during 2000--2007. t ... | 2009 | 19609248 |
| development of a macrophage cell culture method to isolate and enrich francisella tularensis from food matrices for subsequent detection by real-time pcr. | francisella tularensis is a gram-negative bacterium that can cause gastrointestinal or oropharyngeal tularemia in humans from ingestion of contaminated food or water. despite the potential for accidental or intentional contamination of foods with f. tularensis, there are no techniques currently available to detect this organism in specific food matrices. in this study, a macrophage cell culture system is combined with real-time pcr to identify f. tularensis in food matrices. the method utilizes ... | 2009 | 19610325 |
| description of two new plasmids isolated from francisella philomiragia strains and construction of shuttle vectors for the study of francisella tularensis. | francisella tularensis is the causative agent of tularemia, a zoonotic disease often transmitted to humans by infected animals. the lack of useful specific genetic tools has long hampered the study of f. tularensis subspecies. we identified and characterized two new plasmids, pf242 and pf243, isolated from francisella philomiragia strains atcc 25016 and atcc 25017, respectively. sequence analysis revealed that pf242 and pf243 are closely related to pc194 and pfnl10 plasmids, respectively. two ge ... | 2009 | 19615403 |
| epitope-based vaccination against pneumonic tularemia. | francisella tularensis, the etiological agent of tularemia, is one of the most infectious bacterial pathogens known. no vaccine is currently approved for public use. previously, we identified epitopes recognized specifically by t cells obtained from individuals following infection with f. tularensis. here, we report that a subunit vaccine constructed based upon these epitopes elicited protective immunity in "humanized" hla class ii (drb1*0401) transgenic mice. vaccinated mice challenged intratra ... | 2009 | 19616492 |
| tam receptors are dispensable in the phagocytosis and killing of bacteria. | many receptors that are employed for the engulfment of apoptotic cells are also used for the recognition and phagocytosis of bacteria. tyro3, axl, and mertk (tam) are important in the phagocytosis of apoptotic cells by macrophages. animals lacking these receptors are hypersensitive to bacterial products. in this report, we examine whether the tam receptors are involved in the phagocytosis of bacteria. we found that macrophages lacking mertk, axl, tyro3 or all three receptors were equally efficie ... | 2009 | 19625016 |
| metapopulation structure for perpetuation of francisella tularensis tularensis. | outbreaks of type a tularemia due to francisella tularensis tularensis are typically sporadic and unstable, greatly hindering identification of the determinants of perpetuation and human risk. martha's vineyard, massachusetts has experienced an outbreak of type a tularemia which has persisted for 9 years. this unique situation has allowed us to conduct long-term eco-epidemiologic studies there. our hypothesis is that the agent of type a tularemia is perpetuated as a metapopulation, with many sma ... | 2009 | 19627585 |
| vaccination with an attenuated strain of francisella novicida prevents t-cell depletion and protects mice infected with the wild-type strain from severe sepsis. | francisella tularensis is the causative agent of zoonotic tularemia, a severe pneumonia in humans, and francisella novicida causes a similarly severe tularemia in mice upon inhalation. the correlates of protective immunity, as well as the virulence mechanisms of this deadly pathogen, are not well understood. in the present study, we compared the host immune responses of lethally infected and vaccinated mice to highlight the host determinants of protection from this disease. intranasal infection ... | 2009 | 19635830 |
| evidence for the presence of francisella and spotted fever group rickettsia dna in the tick amblyomma fimbriatum (acari: ixodidae), northern territory, australia. | ticks (n = 252) were collected from five wild-caught reptile species during routine trapping in the djukbinj national park and fogg dam reserve, northern territory, australia. pooling of ticks (one to four ticks per pool), according to sex or host animal, resulted in 187 samples used for screening for the presence of rickettsia species via molecular methods. rickettsia dna was detected via the amplification of the glta, ompa, and ompb genes in 57 (34%) of the 187 tick samples, all of which conta ... | 2009 | 19645299 |
| vaccination with a defined francisella tularensis subsp. novicida pathogenicity island mutant (deltaiglb) induces protective immunity against homotypic and heterotypic challenge. | francisella tularensis, an intracellular gram-negative bacterium, is the causative agent of tularemia and a potential bioweapon. currently, there is no licensed vaccine against this organism. we have characterized the efficacy of a defined f. tularensis subsp. novicida mutant (deltaiglb) as a live attenuated vaccine against pneumonic tularemia. replication of the iglb mutant (kkf235) in murine macrophages was significantly lower than the wild type novicida strain u112, and exhibited an ld(50) gr ... | 2009 | 19651173 |
| the 58-kilodalton major virulence factor of francisella tularensis is required for efficient utilization of iron. | we investigated the role of the 58-kda ftt0918 protein in the iron metabolism of francisella tularensis. the phenotypes of schu s4, a prototypic strain of f. tularensis subsp. tularensis, and the delta ftt0918 and delta fsla isogenic mutants were analyzed. the gene product missing in the delta fsla mutant is responsible for synthesis of a siderophore. when grown in broth with various iron concentrations, the two deletion mutants generally reached lower maximal densities than schu s4. the delta f ... | 2009 | 19651867 |
| loops and networks in control of francisella tularensis virulence. | francisella tularensis is a highly infectious, gram-negative bacterium responsible for the disease tularemia in a broad variety of animals, including humans. f. tularensis intracellular multiplication occurs mainly in macrophages. however, f. tularensis is able to infect many other cell types, including other phagocytic (dendritic cells, polymorphonuclear leukocytes) and nonphagocytic (alveolar epithelial cells, hepatocytes, endothelial cells and fibroblasts) cells. the ability of professional p ... | 2009 | 19659427 |
| functional analyses of pilin-like proteins from francisella tularensis: complementation of type iv pilus phenotypes in neisseria gonorrhoeae. | accumulating evidence from a number of studies strongly suggests that proteins orthologous to those involved in type iv pili (tfp) assembly and function are required for francisella pathogenicity. however, the molecular mechanisms by which the components exert their influence on virulence remain poorly understood. owing to the conservation and promiscuity of tfp biogenesis machineries, expression of tfp pilins in heterologous species has been used successfully to analyse organelle structure-func ... | 2009 | 19423631 |
| identification of genes contributing to the virulence of francisella tularensis schu s4 in a mouse intradermal infection model. | francisella tularensis is a highly virulent human pathogen. the most virulent strains belong to subspecies tularensis and these strains cause a sometimes fatal disease. despite an intense recent research effort, there is very limited information available that explains the unique features of subspecies tularensis strains that distinguish them from other f. tularensis strains and that explain their high virulence. here we report the use of targeted mutagenesis to investigate the roles of various ... | 2009 | 19424499 |
| comparison of traditional and molecular analytical methods for detecting biological agents in raw and drinking water following ultrafiltration. | to compare the performance of traditional methods to quantitative polymerase chain reaction (qpcr) for detecting five biological agents in large-volume drinking-water samples concentrated by ultrafiltration (uf). | 2009 | 19426268 |
| pivotal role of the francisella tularensis heat-shock sigma factor rpoh. | francisella tularensis is a highly infectious pathogen that infects animals and humans to cause the disease tularemia. the primary targets of this bacterium are macrophages, in which it replicates in the cytoplasm after escaping the initial phagosomal compartment. the ability to replicate within macrophages relies on the tightly regulated expression of a series of genes. one of the most commonly used means of coordinating the regulation of multiple genes in bacteria consists of the association o ... | 2009 | 19443547 |
| [effect of serotonin and dopamine on growth of yersinia pestis and francisella tularensis strains]. | to study the effects of serotonin and dophamine on the growth of yersinia pestis and francisella tularensis strains as well as ability of monoamines to change susceptibility of experimental animals to plague infection. | 2009 | 19459486 |
| [development of a multiplex pcr-suspension array for simultaneous detection of five bioterrorism bacteria]. | to develop a rapid, high-throughput screening method of gene suspension array technique to simultaneously detect five bioterrorism bacteria: bacillus anthracis, francisella tularensis, yersinia pestis, brucella spp. and burkholderia pseudomallei. | 2009 | 19462919 |
| comparative genomic characterization of francisella tularensis strains belonging to low and high virulence subspecies. | tularemia is a geographically widespread, severely debilitating, and occasionally lethal disease in humans. it is caused by infection by a gram-negative bacterium, francisella tularensis. in order to better understand its potency as an etiological agent as well as its potential as a biological weapon, we have completed draft assemblies and report the first complete genomic characterization of five strains belonging to the following different francisella subspecies (subsp.): the f. tularensis sub ... | 2009 | 19478886 |
| laboratory-acquired infections. | laboratory-acquired infections due to a wide variety of bacteria, viruses, fungi, and parasites have been described. although the precise risk of infection after an exposure remains poorly defined, surveys of laboratory-acquired infections suggest that brucella species, shigella species, salmonella species, mycobacterium tuberculosis, and neisseria meningitidis are the most common causes. infections due to the bloodborne pathogens (hepatitis b virus, hepatitis c virus, and human immunodeficiency ... | 2009 | 19480580 |
| differential susceptibility of sprague-dawley and fischer 344 rats to infection by francisella tularensis. | the type a and b subspecies of francisella tularensis cause severe disease, tularemia, in humans. however, only the former can be lethal especially if inhaled. it is likely that non-lethal infection is due at least in part to the ability of innate host defenses to control pathogen growth whilst acquired immunity develops. most common small laboratory animals rapidly succumb to clinical strains of f. tularensis and are, therefore, poor models with which to study innate immunity. in an attempt to ... | 2009 | 19490832 |
| mucosal immunotherapy for protection from pneumonic infection with francisella tularensis. | previous studies have demonstrated that systemically administered immunotherapy can protect mice from systemic challenge with the bacterial pathogen francisella tularensis. however, for protection from inhalational challenge with this bacterium, we wondered if mucosally administered immunotherapy might be more effective. therefore, we administered cationic liposome-dna complexes (cldc), which are potent activators of innate immunity, intranasally (i.n.) and assessed the effectiveness of protecti ... | 2009 | 19490961 |
| pyrin critical to macrophage il-1beta response to francisella challenge. | relative to monocytes, human macrophages are deficient in their ability to process and release il-1beta. in an effort to explain this difference, we used a model of il-1beta processing and release that is dependent upon bacterial escape into the cytosol. fresh human blood monocytes were compared with monocyte-derived macrophages (mdm) for their il-1beta release in response to challenge with francisella novicida. although both cell types produced similar levels of il-1beta mrna and intracellular ... | 2009 | 19494323 |
| transovarial transmission of francisella-like endosymbionts and anaplasma phagocytophilum variants in dermacentor albipictus (acari: ixodidae). | dermacentor albipictus (packard) is a north american tick that feeds on cervids and livestock. it is a suspected vector of anaplasmosis in cattle, but its microbial flora and vector potential remain underevaluated. we screened d. albipictus ticks collected from minnesota white-tailed deer (odocoileus virginianus) for bacteria of the genera anaplasma, ehrlichia, francisella, and rickettsia using polymerase chain reaction (pcr) gene amplification and sequence analyses. we detected anaplasma phagoc ... | 2009 | 19496436 |
| contribution of citrulline ureidase to francisella tularensis strain schu s4 pathogenesis. | the citrulline ureidase (ctu) activity has been shown to be associated with highly virulent francisella tularensis strains, including schu s4, while it is absent in avirulent or less virulent strains. a definitive role of the ctu gene in virulence and pathogenesis of f. tularensis schu s4 has not been assessed; thus, an understanding of the significance of this phenotype is long overdue. ctu is a carbon-nitrogen hydrolase encoded by the citrulline ureidase (ctu) gene (ftt0435) on the f. tularens ... | 2009 | 19502406 |
| reintroduction of two deleted virulence loci restores full virulence to the live vaccine strain of francisella tularensis. | a disadvantage of several old vaccines is that the genetic events resulting in the attenuation are often largely unknown and reversion to virulence cannot be excluded. in the 1950s, a live vaccine strain, lvs, was developed from a type b strain of francisella tularensis, the causative agent of tularemia. lvs, which is highly attenuated for humans but still virulent for mice by some infection routes, has been extensively studied and found to protect staff from laboratory-acquired tularemia. the e ... | 2009 | 19506014 |
| francisella sp., an emerging pathogen of tilapia, oreochromis niloticus (l.), in costa rica. | francisella sp. is an emergent bacterial pathogen that causes acute to chronic disease in warm and cold water cultured and wild fish species. during the past 3 years, the bacterium has been detected in tilapia, oreochromis niloticus, cultured in costa rica. infected fish presented non-specific clinical signs, such as erratic swimming, anorexia, anaemia, exophthalmia and high mortality. upon macroscopic and microscopic examination, several internal organs (mainly spleen and kidney) were enlarged ... | 2009 | 19515205 |
| vaccination of fischer 344 rats against pulmonary infections by francisella tularensis type a strains. | pneumonic tularemia caused by inhalation of the type a strains of francisella tularensis is associated with high morbidity and mortality in humans. the only vaccine known to protect humans against this disease is the attenuated live vaccine strain (lvs), but it is not currently registered for human use. to develop a new generation of vaccines, multiple animal models are needed that reproduce the human response to f. tularensis infection and vaccination. we examined the potential use of fischer 3 ... | 2009 | 19520198 |
| molecular evolutionary consequences of niche restriction in francisella tularensis, a facultative intracellular pathogen. | francisella tularensis is a potent mammalian pathogen well adapted to intracellular habitats, whereas f. novicida and f. philomiragia are less virulent in mammals and appear to have less specialized lifecycles. we explored adaptations within the genus that may be linked to increased host association, as follows. first, we determined the genome sequence of f. tularensis subsp. mediasiatica, the only subspecies that had not been previously sequenced. this genome, and those of 12 other f. tularensi ... | 2009 | 19521508 |
| environmental adaptation of francisella tularensis. | concerns over weaponizable bacteria have recently prompted considerable interest in francisella tularensis (ft). in addition to its potential illicit use, ft occurs naturally in diverse ecological niches including mammals, arthropods, and fresh water protozoans. here we review the current knowledge of ft adaptation which has ramifications for both basic and applied research. | 2009 | 19524059 |
| analyzing time-dependent microarray data using independent component analysis derived expression modes from human macrophages infected with f. tularensis holartica. | the analysis of large-scale gene expression profiles is still a demanding and extensive task. modern machine learning and data mining techniques developed in linear algebra, like independent component analysis (ica), become increasingly popular as appropriate tools for analyzing microarray data. we applied ica to analyze kinetic gene expression profiles of human monocyte derived macrophages (mdm) from three different donors infected with francisella tularensis holartica and compared them to more ... | 2009 | 19535009 |
| rationally designed tularemia vaccines. | tularemia, caused by the gram-negative bacterium francisella tularensis, can be contracted by the bite of an arthropod vector or by inhalation. this disease occurs relatively infrequently but can be severe and even life-threatening if untreated. until recently, there were few laboratories studying this organism; however, concerns over its potential use as a biological weapon have led to renewed attention to f. tularensis research, particularly in the area of vaccine development. advances in the ... | 2009 | 19538114 |
| pharmacological exploitation of an off-target antibacterial effect of the cyclooxygenase-2 inhibitor celecoxib against francisella tularensis. | francisella tularensis, a bacterium which causes tularemia in humans, is classified as a cdc category a bioterrorism agent. in this study, we demonstrate that celecoxib, an anti-inflammatory cyclooxygenase-2 inhibitor in clinical use, exhibits activity against a type a strain of f. tularensis (schu s4), the live vaccine strain of f. tularensis (a type b strain), and f. novicida ("f. tularensis subsp. novicida") directly in growth medium. this bacterial killing, however, was not noted with rofeco ... | 2009 | 19398640 |
| lethal pulmonary infection with francisella novicida is associated with severe sepsis. | the bacterial or host determinants of lethality associated with respiratory francisella infections are currently unknown. no exo- or endotoxins that contribute to the severity of this disease have been identified. however, a deregulated host immune response upon infection is characterized by an initial 36- to 48-h delay followed by a rapid and excessive inflammatory response prior to death at 72-120 h. here, we extend these findings by comparing host immune responses between sublethal and lethal ... | 2009 | 19401387 |
| generalized tularemia in a vervet monkey (chlorocebus aethiops) and a patas monkey (erythrocebus patas) in a zoo. | generalized tularemia was diagnosed in a vervet monkey (chlorocebus aethiops) and a patas monkey (erythrocebus patas), both of which died suddenly in the szeged zoo, szeged, hungary. macroscopic lesions in each animal included disseminated, grayish-white foci in the lungs, lymph nodes, spleen, liver, and kidney. all focal lesions were characterized microscopically as purulent to pyogranulomatous to granulomatous inflammation with necrosis. francisella tularensis subsp. holarctica strains were is ... | 2009 | 19407096 |
| the role of complement opsonization in interactions between f. tularensis subsp. novicida and human neutrophils. | the remarkable infectiousness of francisella tularensis suggests that the bacterium efficiently evades innate immune responses that typically protect the host during its continuous exposure to environmental and commensal microbes. in our studies of the innate immune response to f. tularensis, we have observed that, unlike the live vaccine strain (lvs) of f. tularensis subsp. holarctica, f. tularensis subsp. novicida u112 opsonized in pooled human serum activated the nadph oxidase when incubated ... | 2009 | 19409509 |
| ticks and tick-borne pathogens and putative symbionts of black bears (ursus americanus floridanus) from georgia and florida. | ticks were collected from 38 black bears (ursus americanus floridanus) from northwestern florida (n = 18) from 2003 to 2005 and southern georgia (n = 20) in 2006. five species (amblyomma americanum, a. maculatum, dermacentor variabilis, ixodes scapularis, and i. affinis) were collected from florida bears, and 4 species (a. americanum, a. maculatum, d. variabilis, i. scapularis) were collected from bears in georgia. ixodes scapularis was the most frequently collected tick, followed by d. variabil ... | 2009 | 19413369 |
| direct isolation of francisella spp. from environmental samples. | to develop a selective medium for isolation of f. tularensis, f. novicida and f. philomiragia from environmental samples. | 2009 | 19413814 |
| itraq quantitative analysis of francisella tularensis ssp. holarctica live vaccine strain and francisella tularensis ssp. tularensis schu s4 response to different temperatures and stationary phases of growth. | proteomics has been shown to significantly contribute to the investigation of the pathogenicity of the extremely infectious bacteria francisella tularensis. in this study, the authors employed itraq quantitative proteomic analysis in order to monitor alterations in proteomes of f. tularensis ssp. holarctica live vaccine strain and f. tularensis ssp. tularensis schu s4 associated with the cultivation at different temperatures or in the stationary phase. correlated production of the identified pro ... | 2009 | 19415661 |
| comparison of antibody responses in atlantic cod (gadus morhua l.) to vibrio anguillarum, aeromonas salmonicida and francisella sp. | bacterial diseases such as vibriosis, atypical furunculosis and francisellosis, are registered as an increasing problem in cod farming in norway. in order to develop efficient vaccines against diseases it is of interest to investigate if the cod immune system differentiates between various serotypes of vibrio anguillarum and variants of aeromonas salmonicida associated with the diseases by raising specific antibody responses. cod of the same origin were shown to raise significant responses to v. ... | 2009 | 19084603 |
| functional expression of francisella tularensis fabh and fabi, potential antibacterial targets. | francisella tularensis is an extremely infectious airborne pathogen that has long been considered as a potential biological weapon. enzymes of fatty acid synthesis (fas) pathway are attractive targets for the development of new antibacterial agents because of differences between the biosynthesis pathways of bacteria and mammals. we report here the first expression of three functional enzymes in f. tularensis fas-ii pathway: fabh (3-oxoacyl-acyl carrier protein synthase iii) which initiates elong ... | 2009 | 19095065 |
| does the trojan horse have an achilles' heel? | 2009 | 19118310 | |
| re-emergence of tularemia in turkey. | four tularemia epidemics were reported from three different regions of turkey between 1936 and 1953. after a long interval, a new tularemia epidemic was reported from the area around bursa in the northwestern part of turkey in 1988. following this first epidemic in bursa, small epidemics occurred in areas around bursa between 1988 and 2002. other tularemia epidemics in different regions of turkey were reported between 1988 and 2005. almost all of the cases involved the oropharyngeal form of the ... | 2009 | 19119037 |
| influence of nutrient status and grazing pressure on the fate of francisella tularensis in lake water. | the natural reservoir of francisella tularensis, the causative agent of tularaemia, is yet to be identified. we investigated the possibility that francisella persists in natural aquatic ecosystems between outbreaks. it was hypothesized that nutrient-rich environments, with strong protozoan predation, favour the occurrence of the tularaemia bacterium. to investigate the differences in adaptation to aquatic environments of the species and subspecies of francisella, we screened 23 strains for their ... | 2009 | 19120459 |
| recombinant attenuated listeria monocytogenes vaccine expressing francisella tularensis iglc induces protection in mice against aerosolized type a f. tularensis. | fransicella tularensis, the causative agent of tularemia, is in the top category (category a) of potential agents of bioterrorism. to develop a safer vaccine against aerosolized f. tularensis, we have employed an attenuated listeria monocytogenes, which shares with f. tularensis an intracellular and extraphagosomal lifestyle, as a delivery vehicle for f. tularensis antigens. we constructed recombinant l. monocytogenes (rlm) vaccines stably expressing seven f. tularensis proteins including iglc ( ... | 2009 | 19126421 |