Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| characterization of francisella sp., gm2212, the first francisella isolate from marine fish, atlantic cod (gadus morhua). | a francisella sp., isolate gm2212(t), previously isolated from diseased farmed atlantic cod gadus morhua in norway is characterized. the complete 16s rdna, 16s-23s intergenic spacer, 23s rdna, 23s-5s intergenic spacer, 5s rdna, fopa, lipoprotein tul4 (lpna), malate dehydrogenase and a hypothetical lipoprotein (lpnb) is sequenced and compared with francisella tularensis and francisella philomiragia. all these sequences support a close relationship between gm2212(t) and f. philomiragia. the bacter ... | 2007 | 17160676 |
| a case of tularemia presenting as a dental abscess: case report. | objective: the purpose of this report is to present a tularemia case accompanied by a neck mass that easily may be confounded with dental abscess. summary: francisella tularensis is a potential agent of biologic terrorism. thirty percent of the symptoms seen in tularemia localize in the head and neck region and are sometimes mistaken for complications of a dental abscess. to our knowledge, reports of the differential diagnostic characteristics of tularemia are lacking in the dental literature an ... | 2007 | 17178484 |
| coactivating signals for the hepatic lymphocyte gamma interferon response to francisella tularensis. | the facultative intracellular bacterium francisella tularensis is capable of causing systemic infections in various hosts, including mice and humans. the liver is a major secondary site of f. tularensis infection, but hepatic immune responses to the pathogen remain poorly defined. immune protection against the pathogen is thought to depend on the cytokine gamma interferon (ifn-gamma), but the cellular basis for this response has not been characterized. here we report that natural killer cells fr ... | 2007 | 17178781 |
| tularemia re-emerging in european part of turkey after 60 years. | the aim of this study was to investigate a tularemia outbreak in the thrace region of turkey. the outbreak occurred in demirkoy village of edirne, in 2005. of 400 villagers, 266 were examined and their sera were taken. throat swabs and lymph node aspirates were cultured. specific antibodies in patients and domestic animals were screened by a microagglutination test. pcr assays and cultures of the samples of patients, animal tissues, and water sources were performed, along with active surveillanc ... | 2006 | 17186960 |
| matrix metalloproteinase 9 activity enhances host susceptibility to pulmonary infection with type a and b strains of francisella tularensis. | a striking feature of pulmonary infection with the gram-negative intracellular bacterium francisella tularensis, a category a biological threat agent, is an intense accumulation of inflammatory cells, particularly neutrophils and macrophages, at sites of bacterial replication. given the essential role played by host matrix metalloproteinases (mmps) in modulating leukocyte recruitment and the potentially indiscriminate destructive capacity of these cells, we investigated whether mmp-9, an importa ... | 2007 | 17202364 |
| resistance of francisella tularensis strains against reactive nitrogen and oxygen species with special reference to the role of katg. | francisella tularensis is a facultative intracellular bacterial pathogen capable of proliferating within host macrophages. the mechanisms that explain the differences in virulence between various strains of the species are not well characterized. in the present study, we show that both attenuated (strain lvs) and virulent (strains fsc200 and schu s4) strains of the pathogen replicate at similar rates in resting murine peritoneal exudate cells (pec). however, when pec were activated by exposure t ... | 2007 | 17210667 |
| a comprehensive transposon mutant library of francisella novicida, a bioweapon surrogate. | francisella tularensis, the causative agent of tularemia, is one of the most infectious bacterial pathogens known and is a category a select agent. we created a sequence-defined, near-saturation transposon mutant library of f. tularensis novicida, a subspecies that causes a tularemia-like disease in rodents. the library consists of 16,508 unique insertions, an average of >9 insertions per gene, which is a coverage nearly twice that of the greatest previously achieved for any bacterial species. i ... | 2007 | 17215359 |
| portable 24-analyte surface plasmon resonance instruments for rapid, versatile biodetection. | field use of surface plasmon resonance (spr) biosensors for environmental and defense applications such as detection and identification of biological warfare agents has been hampered by lack of rugged, portable, high-performance instrumentation. to meet this need, we have developed compact multi-analyte spr instruments based on texas instruments' spreeta sensing chips. the instruments weigh 3 kg and are built into clamshell enclosures measuring 28 cm x 22 cm x 13 cm. functions are divided betwee ... | 2007 | 17223032 |
| proteomics analysis of the francisella tularensis lvs response to iron restriction: induction of the f. tularensis pathogenicity island proteins iglabc. | francisella tularensis is a highly virulent, facultative intracellular pathogen that causes tularemia in humans and animals. although it is one of the most infectious bacterial pathogens, little is known about its virulence mechanisms. in this study, the response of f. tularensis live vaccine strain to iron depletion, which simulates the environment within the host, was investigated. in order to detect alterations in protein synthesis, metabolic labeling, followed by 2d-page analysis was used. g ... | 2007 | 17227466 |
| the francisella pathogenicity island protein igla localizes to the bacterial cytoplasm and is needed for intracellular growth. | francisella tularensis is a gram negative, facultative intracellular bacterium that is the etiological agent of tularemia. f. novicida is closely related to f. tularensis but has low virulence for humans while being highly virulent in mice. igla is a 21 kda protein encoded by a gene that is part of an iglabcd operon located on the francisella pathogenicity island (fpi). | 2007 | 17233889 |
| identification of immunoreactive antigens in membrane proteins enriched fraction from francisella tularensis lvs. | francisella tularensis is a gram-negative, facultative intracellular bacterium causing disease in many mammalian species. the low infectious dose of f. tularensis and the ease of air-borne transmission are the main features responsible for the classification of this bacterium as a potential biological weapon. the live attenuated strain of f. tularensis live vaccine strain (lvs) is currently only effective vaccine against tularemia, however, this type of vaccine has not been approved for human us ... | 2007 | 17241671 |
| a francisella tularensis subspecies novicida purf mutant, but not a pura mutant, induces protective immunity to tularemia in mice. | francisella tularensis subspecies novicida mutants have been made with deletions introduced into the pura or purf genes. these mutants demonstrated the expected growth requirement for purines and complementation with the wild type genes restored the ability to grow on purine deficient media. the mutants were at least 10,000-fold attenuated by the ip challenge route in balb/c mice and defective for survival in j774a.1 mouse macrophages. immunisation with the pura mutant did not provide protection ... | 2007 | 17241711 |
| mouse model of oral infection with virulent type a francisella tularensis. | francisella tularensis is a gram-negative facultative intracellular pathogen and the causative agent of tularemia. little is known about the immunopathogenesis of oral infection with this pathogen. here, for the first time, we examined the susceptibility of mice to intragastric inoculation with virulent type a f. tularensis and characterized the course of infection and the associated host responses. both immunocompetent and immunodeficient mice were relatively susceptible to intragastric inocula ... | 2007 | 17242058 |
| [francisella tularensis--feature of pathogen, pathogenesis, diagnostics]. | francisella tularensis belongs to the francisellaceae family. there are four known subspecies of francisella tularensis: tularensis, holarctica, mediasiatica and novicida. fully virulent strains possess a capsule, which protects f. tularensis from bactericidal action of serum. the main virulen factors of f. tularensis are 23-kda cytoplasmatic protein and lps. f tularensis mechanism of pathogenecity is very unique. f. lularensis affect macrophages using a cytochalasin b intensive pathway. bacteri ... | 2006 | 17249186 |
| characterization of lipid a acylation patterns in francisella tularensis, francisella novicida, and francisella philomiragia using multiple-stage mass spectrometry and matrix-assisted laser desorption/ionization on an intermediate vacuum source linear ion trap. | lipopolysaccharide (lps) is a major component of the outer membrane of gram-negative bacteria. the lipid a region of lps stimulates the immune system in a structure-dependent manner. we have previously identified the two major lipid a species from francisella tularensis as asymmetric tetraacylated structures containing four long acyl chains (16 and 18 carbons) and a single phosphate group that is partially modified by galactosamine (phillips, n. j.; schilling b.; mclendon, m. k.; apicella, m. a. ... | 2007 | 17263332 |
| francisella tularensis-infected macrophages release prostaglandin e2 that blocks t cell proliferation and promotes a th2-like response. | francisella tularensis is a highly infectious bacterial pathogen, and is likely to have evolved strategies to evade and subvert the host immune response. in this study, we show that f. tularensis infection of macrophages alters t cell responses in vitro, by blocking t cell proliferation and promoting a th2-like response. we demonstrate that a soluble mediator is responsible for this effect and identify it as pge(2). supernatants from f. tularensis-infected macrophages inhibited il-2 secretion fr ... | 2007 | 17277110 |
| real-time pcr for francisella tularensis types a and b. | 2006 | 17283646 | |
| [natural foci of tularemia on the wrangel island]. | the subjects of the study were snowy owl castings (611 samples), polar fox litters (148 samples), and water samples of outdoor tundra water reservoirs. tularemia antigen was sought in the castings and litters by the antibody neutralization test. the water was examined by bioassays. tularemia antigen was annually detected in the study samples. epizootically active autonomous natural foci of tundra-type tularemia were ascertained to continue to exist on the wrangel island. the major vectors of the ... | 2006 | 17290906 |
| diversity of francisella tularensis schu4 antigens recognized by t lymphocytes after natural infections in humans: identification of candidate epitopes for inclusion in a rationally designed tularemia vaccine. | the t lymphocyte antigens, which may have a role in protection against tularemia, were predicted by immunoinformatics analysis of francisella tularensis schu4. twenty-seven class ii putative promiscuous epitopes and 125 putative class i supertype epitopes were chosen for synthesis; peptides were tested in vitro for their ability to bind hla and to induce immune responses from pbmcs of 23 previously infected subjects. while the immune responses of individual subjects showed heterogeneity, 95% of ... | 2007 | 17291638 |
| simultaneous real-time pcr detection of bacillus anthracis, francisella tularensis and yersinia pestis. | this report describes the development of in-house real-time pcr assays using minor groove binding probes for simultaneous detection of the bacillus anthracis pag and cap genes, the francisella tularensis 23 kda gene, as well as the yersinia pestis pla gene. the sensitivities of these assays were at least 1 fg, except for the assay targeting the bacillus anthracis cap gene, which showed a sensitivity of 10 fg when total dna was used as a template in a serial dilution. the clinical value of the ba ... | 2007 | 17294160 |
| inactivated francisella tularensis live vaccine strain protects against respiratory tularemia by intranasal vaccination in an immunoglobulin a-dependent fashion. | francisella tularensis is a gram-negative intracellular bacterium that is considered to be a potential category a biological weapon due to its extreme virulence. although vaccination with the attenuated live vaccine strain (lvs) of f. tularensis can protect against lethal challenge, use of inactivated or subunit forms as vaccine candidates for induction of protective antibody responses has not been fully evaluated. in the present study, we examined whether immune protection in the lung could be ... | 2007 | 17296747 |
| a defined o-antigen polysaccharide mutant of francisella tularensis live vaccine strain has attenuated virulence while retaining its protective capacity. | francisella tularensis, the causative agent of tularemia, has been designated a cdc category a select agent because of its low infective dose (<10 cfu), its ready transmission by aerosol, and its ability to produce severe morbidity and high mortality. the identification and characterization of this organism's virulence determinants will facilitate the development of a safe and effective vaccine. we report that inactivation of the wbta-encoded dehydratase of the o-antigen polysaccharide (o-ps) lo ... | 2007 | 17296751 |
| re-emergence of francisella tularensis in germany: fatal tularaemia in a colony of semi-free-living marmosets (callithrix jacchus). | francisella tularensis was identified as the cause of a die-off which occurred among a colony of semi-free-living common marmosets (callithrix jacchus). during the outbreak 5 out of 62 animals died of tularaemia in a research facility located in the district of goettingen, germany. all animals had been born at the facility suggesting an endemic infection. a total of five culture isolates were recovered and characterized as f. tularensis holarctica, biovar i. these cultures represent the first is ... | 2007 | 17306050 |
| suitability of partial 16s ribosomal rna gene sequence analysis for the identification of dangerous bacterial pathogens. | in a bioterrorism event a rapid tool is needed to identify relevant dangerous bacteria. the aim of the study was to assess the usefulness of partial 16s rrna gene sequence analysis and the suitability of diverse databases for identifying dangerous bacterial pathogens. | 2007 | 17309636 |
| comparison of the 2000 and 2005 outbreaks of tularemia in the duzce region of turkey. | tularemia caused by francisella tularensis, which is considered a biological warfare agent, is a widely distributed zoonosis. in this study, we aimed to compare a 2005 outbreak of tularemia that was confirmed as waterborne by pcr to outbreak of tularemia that was reported as waterborne in 2000 and to investigate the changes of epidemiological characteristics between these two outbreaks occurring in the same region. in the present study, a total of 11 patients were diagnosed with tularemia. in th ... | 2007 | 17314427 |
| francisella tularensis vaccines. | francisella tularensis is the causative agent of tularaemia, a disease which occurs naturally in some countries in the northern hemisphere. recently, there has been a high level of interest in devising vaccines against the bacterium because of the potential for it to be used as a bioterrorism agent. previous human volunteer studies have shown that a strain of f. tularensis [the live vaccine strain (lvs)] that has been attenuated by laboratory passage is effective in humans as a vaccine against a ... | 2007 | 17316369 |
| raman chemical imaging spectroscopy reagentless detection and identification of pathogens: signature development and evaluation. | an optical detection method, raman chemical imaging spectroscopy (rcis), is reported, which combines raman spectroscopy, fluorescence spectroscopy, and digital imaging. using this method, trace levels of biothreat organisms are detected in the presence of complex environmental backgrounds without the use of amplification or enhancement techniques. rcis is reliant upon the use of raman signatures and automated recognition algorithms to perform species-level identification. the rationale and steps ... | 2007 | 17338507 |
| an in vitro model system used to study adherence and invasion of francisella tularensis live vaccine strain in nonphagocytic cells. | in observing francisella tularensis interactions with nonphagocytic cell lines in vitro, we noted significant adherence, invasion, and intracellular growth of the bacteria within these cells. f. tularensis live vaccine strain invasion of nonprofessional phagocytic cells is inhibited by cytochalasin d and nocodazole, suggesting that both the actin and microtubule cytoskeletons are important for invasion. | 2007 | 17339345 |
| [prevalence of antibodies to francisella tularensis in forest workers from different regions of poland]. | in the present study we evaluate the prevalence of antibodies to f. tularensis in 480 serum samples obtained from healthy forest workers from different regions of poland. the investigations were performed using the tube agglutination test and elisa. the cut-off limit of serum antibodies was set at mean antibody titre determined in the sera of 115 blood donors exceeded by three standard deviations. in none serum samples we detected antibodies to f. tularensis by tube agglutination test. of the 48 ... | 2006 | 17340995 |
| oral immunization of mice with the live vaccine strain (lvs) of francisella tularensis protects mice against respiratory challenge with virulent type a f. tularensis. | francisella tularensis is a gram-negative intracellular bacterium, and the causative agent of tularemia. the infection can be initiated by various routes and can manifest itself in several clinical forms with the disseminated typhoidal form initiated by inhalation being most fatal. the attenuated live vaccine strain (lvs), developed almost 50 years ago, remains the sole effective tularemia vaccine, which is still only available as an investigational new drug for at-risk individuals. this vaccine ... | 2007 | 17346863 |
| tularemia in deer mice (peromyscus maniculatus) during a population irruption in saskatchewan, canada. | type b tularemia caused by francisella tularensis subsp. holarctica was diagnosed in deer mice (peromyscus maniculatus) found dead at four sites in west-central saskatchewan during april and may 2005. the occurrence of tularemia coincided with a decline in the number of deer mice in part of a large area (>22000 km(2) ) in which deer mice had been extremely abundant during the autumn of 2004 and spring of 2005, and in which mice caused damage to crops in the autumn of 2004. this is apparently the ... | 2007 | 17347390 |
| pathobiology and management of laboratory rodents administered cdc category a agents. | the centers for disease control and prevention category a infectious agents include bacillus anthracis (anthrax), clostridium botulinum toxin (botulism), yersinia pestis (plague), variola major virus (smallpox), francisella tularensis (tularemia), and the filoviruses and arenaviruses that induce viral hemorrhagic fevers. these agents are regarded as having the greatest potential for adverse impact on public health and therefore are a focus of renewed attention in infectious disease research. fre ... | 2007 | 17348288 |
| transcriptome analysis of human immune responses following live vaccine strain (lvs) francisella tularensis vaccination. | the live vaccine strain (lvs) of francisella tularensis is the only vaccine against tularemia available for humans, yet its mechanism of protection remains unclear. we probed human immunological responses to lvs vaccination with transcriptome analysis using pbmc samples from volunteers at time points pre- and post-vaccination. gene modulation was highly uniform across all time points, implying commonality of vaccine responses. principal components analysis revealed three highly distinct principa ... | 2007 | 17349694 |
| [glandular tularemia--case report]. | tularemia is a rare zoonosis occuring in many clinical forms, including ulceral, glandular, oropharyngeal, pneumonic, and septic form. ent specialists seeing their patients in ambulatory and emergency settings are most likely to encounter oropharyngeal and glandular form. tularemia became widely discussed clinical entity in recent years due to its potential to being used as a biological weapon in acts of terrorism. authors present a case of a 75 yrs old woman treated for atypical tonsillitis wit ... | 2006 | 17357677 |
| attenuated virulence of a francisella mutant lacking the lipid a 4'-phosphatase. | francisella tularensis causes tularemia, a highly contagious disease of animals and humans, but the virulence features of f. tularensis are poorly defined. f. tularensis and the related mouse pathogen francisella novicida synthesize unusual lipid a molecules lacking the 4'-monophosphate group typically found in the lipid a of gram-negative bacteria. lpxf, a selective phosphatase located on the periplasmic surface of the inner membrane, removes the 4'-phosphate moiety in the late stages of f. nov ... | 2007 | 17360489 |
| cerebral abscesses complicating tularemia meningitis. | tularemia meningitis is a distinctly rare entity with only 14 cases reported in the literature, half of which occurred prior to 1950. in this case we provide the first description of cerebral microabscesses which occurred as a complication of tularemia meningitis. | 2007 | 17366059 |
| modulation of virulence factors in francisella tularensis determines human macrophage responses. | francisella tularensis, the causative agent of tularemia and category a biodefense agent, is known to replicate within host macrophages, though the pathogenesis of this organism is incompletely understood. we have isolated a variant of f. tularensis live vaccine strain (lvs) based on colony morphology and its effect on macrophages. human monocyte-derived macrophages produced more tumor necrosis factor alpha (tnfalpha), interleukin (il)-1beta, il-6, and il-12 p40 following exposure to the variant ... | 2007 | 17369012 |
| francisella tularensis induces il-23 production in human monocytes. | francisella tularensis, the causative agent of tularemia, is phagocytosed by immune cells such as monocytes and macrophages. instead of being destroyed in the phagolysosome, the bacterium escapes the phagosome and replicates within the host cytosol. recent studies indicate that phagosomal escape may have a major impact on the nature of the inflammatory cytokine response to infection. to better understand the host cell response to francisella infection, we exposed human peripheral blood monocytes ... | 2007 | 17372002 |
| active suppression of the pulmonary immune response by francisella tularensis schu4. | francisella tularensis is an obligate, intracellular bacterium that causes acute, lethal disease following inhalation. as an intracellular pathogen f. tularensis must invade cells, replicate, and disseminate while evading host immune responses. the mechanisms by which virulent type a strains of francisella tularensis accomplish this evasion are not understood. francisella tularensis has been shown to target multiple cell types in the lung following aerosol infection, including dendritic cells (d ... | 2007 | 17372012 |
| optimized application of surface-enhanced laser desorption/ionization time-of-flight ms to differentiate francisella tularensis at the level of subspecies and individual strains. | francisella tularensis, the causative agent of tularaemia, is a potential agent of bioterrorism. the phenotypic discrimination of the closely related f. tularensis subspecies and individual strains with traditional methods is difficult and time consuming, often producing ambiguous results. surface-enhanced laser desorption/ionization time-of-flight ms (seldi-tof ms) was used in this study to discriminate the different species and subspecies of the genus francisella. we tested 18 francisella stra ... | 2007 | 17378900 |
| in vivo negative selection screen identifies genes required for francisella virulence. | francisella tularensis subverts the immune system to rapidly grow within mammalian hosts, often causing tularemia, a fatal disease. this pathogen targets the cytosol of macrophages where it replicates by using the genes encoded in the francisella pathogenicity island. however, the bacteria are recognized in the cytosol by the host's asc/caspase-1 pathway, which is essential for host defense, and leads to macrophage cell death and proinflammatory cytokine production. we used a microarray-based ne ... | 2007 | 17389372 |
| the francisella pathogenicity island. | the francisella pathogenicity island (fpi) is a cluster of 16-19 genes, which is found duplicated in most of the francisella genomes that have been sequenced. although 16 fpi genes are highly conserved there are 2-3 putative genes that are absent or interrupted by stop codons in some strains. francisella strains with experimentally induced mutations in fpi genes are highly attenuated in virulence and show defects in intramacrophage growth. there is experimental evidence indicating that the regul ... | 2007 | 17395722 |
| the structure and function of francisella lipopolysaccharide. | a key factor in the biology of francisella spp. is lipopolysaccharide (lps). francisella lps has many unique structural properties and poorly activates proinflammatory responses due to its lack of interaction with toll-like receptor 4 (tlr4). the lps of this organism can be modified by various carbohydrates including glucose, mannose and galactosamine, which affect various aspects of virulence. spontaneously occurring colony variants of f. tularensis have altered lps. this altered lps may accoun ... | 2007 | 17395723 |
| francisella tularensis: activation of the inflammasome. | francisella tularensis (f. tularensis) is a facultative intracellular pathogen that causes the systemic disease tularemia. this pathogen can replicate in the cytosol of macrophages, an ability that is linked with its virulence. we discuss recent data demonstrating that in macrophages, cytosolic francisella induce the activation of the cysteine protease caspase-1 within a multiprotein complex called the inflammasome. nod-like receptors (nlrs), which may have important roles in innate immunity as ... | 2007 | 17395724 |
| genetics and genetic manipulation in francisella tularensis. | francisella tularensis is a gram-negative coccobacillus and the etiological agent of tularemia. the limited knowledge regarding the interaction of f. tularensis with its host is due in part to the previous lack of tools for genetically manipulating the organism. during the past 10 years, the field of f. tularensis genetics has seen a rapid expansion. plasmids capable of stable or conditional replication in francisella have been constructed. methods for the efficient introduction of dna into fran ... | 2007 | 17395725 |
| tularemia: history, epidemiology, pathogen physiology, and clinical manifestations. | francisella tularensis has been recognized as a human pathogen for almost 100 years and is the etiological agent of the zoonotic disease tularemia. soon after its discovery, it became recognized as an important pathogen in several parts of the world, for example, in the united states and soviet union. the number of tularemia cases in the two countries peaked in the 1940s and has thereafter steadily declined. despite this decline, there was still much interest in the pathogen in the 1950s and 196 ... | 2007 | 17395726 |
| mucosal immunopathogenesis of francisella tularensis. | respiratory infection with francisella tularensis is the deadliest form of disease and represents the most likely route to be used by bioterrorists. although mucosal surfaces represent the first line of defense against respiratory tularemia, and in fact, against the great majority of human pathogens, little is known about protective immunity at these sites. the objective of this chapter is to review recent data examining the importance of various pulmonary immune mechanisms in defense against f. ... | 2007 | 17395728 |
| vaccines against francisella tularensis. | francisella tularensis is one of the most pathogenic pathogens known, especially when disseminated as a small particle aerosol. because of this, it was developed into a biological warfare agent by several states during the 20th century. nowadays, concerns remain about the potential of this pathogen to cause widespread disease, tularemia, in the hands of terrorists. this has resurrected interest in methods to combat it. this article reviews the current status of vaccine development efforts agains ... | 2007 | 17395730 |
| animal models of francisella tularensis infection. | the increased incidence of emerging infections has caused a resurgence in the development of animal models in order to study their pathophysiology and develop therapeutics against them. optimizing these models and improving our ability to extrapolate information from animals to humans is critical because in many cases the animal model will represent the only modality for efficacy testing. francisella tularensis (f. tularensis) is an emerging pathogen that fits this category. while there is a sig ... | 2007 | 17395735 |
| molecular and genetic basis of pathogenesis in francisella tularensis. | the genetic means of pathogenesis of francisella tularensis are poorly understood. f. tularensis is able to survive and replicate within macrophages, and a virulence factor, mgla, has been identified that is essential for this ability. mgla regulates the transcription of genes necessary for intracellular growth, including those located within the francisella pathogenicity island (fpi). the fpi genes are required for intramacrophage growth and virulence, and appear to encode a protein secretion s ... | 2007 | 17395737 |
| galleria mellonella as a model host to study infection by the francisella tularensis live vaccine strain. | we used the killing of galleria mellonella (lepidoptera: pyralidae; the greater wax moth) caterpillar by the live vaccine strain (lvs) of francisella tularensis to develop an invertebrate host system that can be used to study f. tularensis infection and the in vivo effects of antibacterial compounds on f. tularensis lvs. after injection into the insect hemocoel, f. tularensis lvs, killed caterpillars despite the association of lvs with hemocytes. the rate of killing depended on the number of bac ... | 2007 | 17400503 |
| monochloramine inactivation of bacterial select agents. | seven species of bacterial select agents were tested for susceptibility to monochloramine. under test conditions, the monochloramine routinely maintained in potable water would reduce six of the species by 2 orders of magnitude within 4.2 h. bacillus anthracis spores would require up to 3.5 days for the same inactivation with monochloramine. | 2007 | 17400782 |
| genome sequencing shows that european isolates of francisella tularensis subspecies tularensis are almost identical to us laboratory strain schu s4. | francisella tularensis causes tularaemia, a life-threatening zoonosis, and has potential as a biowarfare agent. f. tularensis subsp. tularensis, which causes the most severe form of tularaemia, is usually confined to north america. however, a handful of isolates from this subspecies was obtained in the 1980s from ticks and mites from slovakia and austria. our aim was to uncover the origins of these enigmatic european isolates. | 2007 | 17406676 |
| biosafety and selectable markers. | francisella tularensis (f. tularensis) is one of the most infectious pathogens known. although the disease caused by this bacterium is rarely fatal with appropriate antibiotic therapy, it is often severely debilitating. laboratory work with f. tularensis poses a significant hazard, and it is essential that appropriate laboratory facilities, trained personnel, and suitable working practices are in place in any organization working with this pathogen. work with human virulent strains should be car ... | 2007 | 17416926 |
| genome-wide identification of francisella tularensis virulence determinants. | francisella tularensis is a gram-negative pathogen that causes life-threatening infections in humans and has potential for use as a biological weapon. the genetic basis of the f. tularensis virulence is poorly understood. this study screened a total of 3,936 transposon mutants of the live vaccine strain for infection in a mouse model of respiratory tularemia by signature-tagged mutagenesis. we identified 341 mutants attenuated for infection in the lungs. the transposon disruptions were mapped to ... | 2007 | 17420240 |
| ectoparasite diversity and exposure to vector-borne disease agents in wild rodents in central coastal california. | a survey of wild rodents was performed in the morro bay area of central coastal california to determine serological and polymerase chain reaction (pcr) prevalence of anaplasma phagocytophilum dumler, barbet, bekker, dasch, palmer, ray, rikihisa, and rurangirwa, borrelia burgdorferi johnson, schmidt, hyde, steigerwalt, and brenner, francisella tularensis mccoy, and yersinia pestis yersin; to describe the ectoparasitic fauna on important vector-borne disease hosts; and to determine whether pathoge ... | 2007 | 17427705 |
| multiplexed identification of blood-borne bacterial pathogens by use of a novel 16s rrna gene pcr-ligase detection reaction-capillary electrophoresis assay. | we have developed a novel high-throughput pcr-ligase detection reaction-capillary electrophoresis (pcr-ldr-ce) assay for the multiplexed identification of 20 blood-borne pathogens (staphylococcus epidermidis, staphylococcus aureus, bacillus cereus, enterococcus faecalis, enterococcus faecium, listeria monocytogenes, streptococcus pneumoniae, streptococcus pyogenes, streptococcus agalactiae, escherichia coli, klebsiella pneumoniae, haemophilus influenzae, pseudomonas aeruginosa, acinetobacter bau ... | 2007 | 17428930 |
| type ii secretion and type iv pili of francisella. | francisella tularensis genomes encode homologues of type iv pili. though several f. tularensis genes required for tfp expression are homologous to genes required for type ii secretion (t2s), these gene clusters mainly bear structural signatures that are typical of tfp. there is preliminary evidence that different f. tularensis subspecies express tfp-like surface structures, but there are also some interesting differences between the subspecies. one difference between the nonpathogenic subspecies ... | 2007 | 17435117 |
| uptake and intracellular fate of francisella tularensis in human macrophages. | francisella tularensis is an intracellular pathogen that survives and multiplies within host mononuclear phagocytes. we have shown that uptake of the bacterium by human macrophages occurs by a novel process, "looping phagocytosis," in which the bacterium is engulfed in a spacious, asymmetric, pseudopod loop. whereas looping phagocytosis is resistant to treatment of the f. tularensis with formalin, proteases, or heat, the process is abolished by oxidation of the bacterial carbohydrates with perio ... | 2007 | 17435118 |
| molecular epidemiology, evolution, and ecology of francisella. | tularemia is a disease caused by several subspecies of francisella tularensis, although the severity of the disease varies greatly from subspecies to subspecies. currently, there are four recognized subspecies (tularensis, holarctica, mediasiatica, and novicida), in addition to a second francisella species, f. philomiragia. it is clear from molecular sampling of the environment that these human pathogens are a mere fraction of the francisella diversity. taxonomic nomenclature is now being based ... | 2007 | 17435120 |
| francisella tularensis genomics and proteomics. | the availability of the genome sequences of different strains of francisella tularensis is having a major impact on a wide range of research projects, from understanding the biology of this organism to devising vaccines and diagnostics. comparative genomics and molecular typing methods suggest that the four different subspecies of f. tularensis are genetically distinct groups. although there is a high degree of nucleotide identity between strains, there are numerous dna rearrangements. is elemen ... | 2007 | 17435122 |
| pneumonic tularemia on martha's vineyard: clinical, epidemiologic, and ecological characteristics. | martha's vineyard, massachusetts, is the site of the only two recognized outbreaks of primary pneumonic tularemia in the united states. beginning in 2000 and continuing through 2006, 59 presumed or confirmed tularemia cases have been reported from martha's vineyard, with more than 60% of these presumed to be due to inhalation of the agent. a joint cdc/massachusetts department of public health case-control study identified landscaping activities such as lawnmowing or brush cutting to be important ... | 2007 | 17442781 |
| emerging zoonoses and vector-borne infections affecting humans in europe. | the purpose of this study was to assess and describe the current spectrum of emerging zoonoses between 2000 and 2006 in european countries. a computerized search of the medline database from january 1966 to august 2006 for all zoonotic agents in european countries was performed using specific criteria for emergence. fifteen pathogens were identified as emerging in europe from 2000 to august 2006: rickettsiae spp., anaplasma phagocytophilum, borrelia burgdorferi, bartonella spp., francisella tula ... | 2007 | 17445320 |
| structural heterogeneity and environmentally regulated remodeling of francisella tularensis subspecies novicida lipid a characterized by tandem mass spectrometry. | the structural characterization of environmentally-regulated lipid a derived from francisella tularensis subspecies novicida (fn) u112 is described using negative electrospray ionization with a linear ion trap fourier transform ion cyclotron resonance (it-ft-icr) hybrid mass spectrometer. the results indicate that a unique profile of lipid a molecular structures are synthesized in response to fn growth at 25 degrees c versus 37 degrees c. molecular species were found to be tetra-acylated, sharin ... | 2007 | 17446084 |
| production and characterization of a monoclonal antibody to francisella tularensis lipopolysaccharide. | having the capacity to detect and identify pathogens that can be employed in a bioterror attack is critical from both a public health and defence perspective. immunodiagnostic assays are useful tools for enhancing such detection capabilities. in order to develop an immunodiagnostic assay for the detection of francisella tularensis, a murine monoclonal antibody (mab) was developed, using the live vaccine strain (lvs) of f. tularensis as the inoculating antigen. a single mab, f94g2-1, which is spe ... | 2007 | 17451358 |
| identification of an orphan response regulator required for the virulence of francisella spp. and transcription of pathogenicity island genes. | francisella tularensis is a category a agent of biowarfare/biodefense. little is known about the regulation of virulence gene expression in francisella spp. comparatively few regulatory factors exist in francisella, including those belonging to two-component systems (tcs). however, orphan members of typical tcs can be identified. to determine if orphan tcs members affect francisella gene expression, a gene encoding a product with high similarity to the salmonella pmra response regulator (ftt1557 ... | 2007 | 17452468 |
| type i interferon signaling is required for activation of the inflammasome during francisella infection. | francisella tularensis is a pathogenic bacterium whose virulence is linked to its ability to replicate within the host cell cytosol. entry into the macrophage cytosol activates a host-protective multimolecular complex called the inflammasome to release the proinflammatory cytokines interleukin (il)-1beta and -18 and trigger caspase-1-dependent cell death. in this study, we show that cytosolic f. tularensis subspecies novicida (f. novicida) induces a type i interferon (ifn) response that is essen ... | 2007 | 17452523 |
| development of novel plasmid vectors and a promoter trap system in francisella tularensis compatible with the pfln10 based plasmids. | francisella tularensis is a category a bioterror pathogen which in some cases can cause a severe and fatal human infection. very few virulence factors are known in this species due to the difficulty in working with it as well as the lack of tools for genetic manipulation. this work describes the construction of a shuttle vector that can replicate in escherichia coli and f. tularensis as well as two distinct promoter trap constructs based on the shuttle vector backbone. replication in f. tularens ... | 2007 | 17459476 |
| the biblical plague of the philistines now has a name, tularemia. | an epidemic thought to have been the first instance of bubonic plague in the mediterranean reveals to have been an episode of tularemia. the deadly epidemic took place in the aftermath of the removal of a wooden box from an isolated hebrew sanctuary. death, tumors, and rodents thereafter plagued philistine country. unlike earlier explanations proposed, tularemia caused by francisella tularensis exhaustively explains the outbreak. tularemia fits all the requirements indicated in the biblical text ... | 2007 | 17467189 |
| new approaches to diagnosis and therapy of tularemia. | francisella tularensis is a potent pathogen and a cause of severe human disease. the outcome of tularemia will depend on rapid insertion of appropriate antibiotics. until recently, effective clinical handling was hampered by shortcomings in laboratory diagnostics. no suitable direct methods were available and, because of risks and isolate recovery difficulties associated with laboratory work, culture has been rarely practiced. due to achievements from work on modern technology, however, tularemi ... | 2007 | 17468229 |
| innate and adaptive immunity to francisella. | studies of immune responses to francisella have been conducted for well over 50 years. here, the basic parameters of innate and adaptive immune responses to francisella are reviewed, with an emphasis on those that may contribute directly to protection against infection. although older literature provides a wealth of information on human immune responses to infection and vaccination, most recent information has been derived largely from studies in animals and using animal cells, particularly mice ... | 2007 | 17468235 |
| evaluating the use of fatty acid profiles to identify francisella tularensis. | rapid capillary gas chromatography (gc) with flame-ionization detection was used to determine the cellular fatty acid profiles of francisella tularensis. two subspecies of f. tularensis, the live vaccine strain (lvs) derived from holarctica and a novicida strain utah 112 (u112), were used to compare the extracted fatty acid methyl esters (fames). a data set for the 2 subspecies was prepared using fatty acid profiles of bacteria grown on 2 types of media, mueller-hinton and cysteine heart agar su ... | 2007 | 17474518 |
| diagnostic approaches for oculoglandular tularemia: advantages of pcr. | the authors describe a diagnostic approach that proved to be particularly valuable in rare cases of ocular tularemia registered during the tularemia outbreak in 1997-2005 in bulgaria. the authors describe the laboratory findings and diagnosis of four cases with an oculoglandular form of infection. | 2007 | 17475710 |
| detection of francisella tularensis subsp. holarctica in a european brown hare (lepus europaeus) in thuringia, germany. | the isolation of francisella tularensis subsp. holarctica biovar ii (strain 06t0001) from a european brown hare (lepus europaeus) from thuringia, germany, is described for the first time. identification of the microorganism was carried out by phenotypic characterisation, partial sequencing of the 16s rrna gene and specific pcr using the primers tul4-435/tul4-863 and ftc1/ftc4. the epidemiology of tularemia in germany is discussed and a risk assessment for humans is made. | 2007 | 17482385 |
| epizootic of tularemia in an outdoor housed group of cynomolgus monkeys (macaca fascicularis). | tularemia is a highly contagious infectious zoonosis, transmissible by inoculation, ingestion, or inhalation of the infectious agent francisella tularensis. the disease is perpetuated by infected rodents, blood-sucking arthropods, and by contaminated water. therefore, nonhuman primates housed outdoors may be at risk for exposure. an epizootic of f. tularensis occurred in an indoor/outdoor-housed group of cynomolgus monkeys (macaca fascicularis) at the german primate center. tularemia was diagnos ... | 2007 | 17491074 |
| the 'hittite plague', an epidemic of tularemia and the first record of biological warfare. | a long-lasting epidemic that plagued the eastern mediterranean in the 14th century bc was traced back to a focus in canaan along the arwad-euphrates trading route. the symptoms, mode of infection, and geographical area, identified the agent as francisella tularensis, which is also credited for outbreaks in canaan around 1715 bc and 1075 bc. at first, the 14th century epidemic contaminated an area stretching from cyprus to iraq, and from israel to syria, sparing egypt and anatolia due to quaranti ... | 2007 | 17499936 |
| role of primary human alveolar epithelial cells in host defense against francisella tularensis infection. | francisella tularensis, an intracellular pathogen, is highly virulent when inhaled. alveolar epithelial type i (ati) and type ii (atii) cells line the majority of the alveolar surface and respond to inhaled pathogenic bacteria via cytokine secretion. we hypothesized that these cells contribute to the lung innate immune response to f. tularensis. results demonstrated that the live vaccine strain (lvs) contacted ati and atii cells by 2 h following intranasal inoculation of mice. in culture, primar ... | 2007 | 17502386 |
| a francisella tularensis pathogenicity island protein essential for bacterial proliferation within the host cell cytosol. | francisella tularensis is an intracellular bacterial pathogen, and is a category a bioterrorism agent. within quiescent human macrophages, the f. tularensis pathogenicity island (fpi) is essential for bacterial growth within quiescent macrophages. the f. tularensis-containing phagosome matures to a late endosome-like stage that does not fuse to lysosomes for 1-8 h, followed by gradual bacterial escape into the macrophage cytosol. here we show that the fpi protein igld is essential for intracellu ... | 2007 | 17517064 |
| toll-like receptor 2-mediated signaling requirements for francisella tularensis live vaccine strain infection of murine macrophages. | francisella tularensis, an aerobic, non-spore-forming, gram-negative coccobacillus, is the causative agent of tularemia. we reported previously that f. tularensis live vaccine strain (lvs) elicited strong, dose-dependent nf-kappab reporter activity in toll-like receptor 2 (tlr2)-expressing hek293t cells and proinflammatory gene expression in primary murine macrophages. herein, we report that f. tularensis lvs-induced murine macrophage proinflammatory cytokine gene and protein expression are over ... | 2007 | 17517865 |
| [highly sensitive enzyme-linked assay based on monoclonal antibodies for detection of brucella antigens]. | mice monoclonal antibodies against lypopolysaccharides (lps) of brucella abortus has been obtained and characterized. the antibodies detected lps of b. abortus, b. melitensis and b. suis with high sensivity and specificity and did not react with lps of yersinia enterocolitica o:3, y. enterocolitica o:9, salmonella typhimurium, and francisella tularensis. it has been shown that interaction of monoclonal antibodies and lps of brucella species can be critically dependent from buffer system. obtaine ... | 2007 | 17523430 |
| pcr and in situ hybridization for the detection and localization of a new pathogen francisella-like bacterium (flb) in ornamental cichlids. | archived formalin-fixed, paraffin-embedded tissues from 28 diseased ornamental cichlid fish associated with visceral granulomas were examined by polymerase chain reaction (pcr) and in situ hybridization (ish) for detection of francisella-like bacteria (flb). the 16s rdna flb-specific primer pair 180f/465r was used on naturally infected ornamental cichlids, resulting in 11 positive cases (39%). using dna probes, all 28 cases (100%) showed a positive reaction, and most labeled cells were observed ... | 2007 | 17523541 |
| immunodominant francisella tularensis antigens identified using proteome microarray. | stimulation of protective immune responses against intracellular pathogens is difficult to achieve using non-replicating vaccines. balb/c mice immunized by intramuscular injection with killed francisella tularensis (live vaccine strain) adjuvanted with preformed immune stimulating complexes admixed with cpg, were protected when systemically challenged with a highly virulent strain of f. tularensis (schu s4). serum from immunized mice was used to probe a whole proteome microarray in order to iden ... | 2007 | 17533643 |
| francisella tularensis has a significant extracellular phase in infected mice. | the ability of francisella tularensis to replicate in macrophages has led many investigators to assume that it resides primarily intracellularly in the blood of mammalian hosts. we have found this supposition to be untrue. in almost all cases, the majority of f. tularensis recovered from the blood of infected mice was in plasma rather than leukocytes. this distribution was observed irrespective of size of inoculum, route of inoculation, time after inoculation, or virulence of the infecting strai ... | 2007 | 17538893 |
| a call for renewed research on tick-borne francisella tularensis in the arkansas-missouri primary national focus of tularemia in humans. | arkansas-missouri has emerged as the primary u.s. focus of tularemia, which is caused by the national institute of allergy and infectious diseases category a priority pathogen francisella tularensis, over the past 30 yr. there are several pieces of indirect evidence suggesting that a key role of ticks in the transmission of f. tularensis to humans in arkansas-missouri is the primary reason why tularemia has remained a prominent disease of humans in this two-state area while fading away from othe ... | 2007 | 17547223 |
| comparison of francisella tularensis genomes reveals evolutionary events associated with the emergence of human pathogenic strains. | francisella tularensis subspecies tularensis and holarctica are pathogenic to humans, whereas the two other subspecies, novicida and mediasiatica, rarely cause disease. to uncover the factors that allow subspecies tularensis and holarctica to be pathogenic to humans, we compared their genome sequences with the genome sequence of francisella tularensis subspecies novicida u112, which is nonpathogenic to humans. | 2007 | 17550600 |
| francisella tularensis, portugal. | 2007 | 17561575 | |
| [determination of the content of water in dry preparations of the vaccine strain francisella tularensis by nmr-relaxation technique]. | frozen-dried preparations were studied for the impact of moisture content of the nuclear magnetic resonance parameter that was a ratio of the amplitudes of a slow component and a rapid one of a free induction signal from the protons of samples. it was found that there was a linear correlation between this parameter and the moisture content of biological materials, by using bovine serum albumin (bsa) as examples, with lactose and biomass of francisella tularensis. formulas were derived for calcul ... | 2007 | 17561666 |
| twin rna polymerase-associated proteins control virulence gene expression in francisella tularensis. | the mgla protein is the only known regulator of virulence gene expression in francisella tularensis, yet it is unclear how it functions. f. tularensis also contains an mgla-like protein called sspa. here, we show that mgla and sspa cooperate with one another to control virulence gene expression in f. tularensis. using a directed proteomic approach, we show that both mgla and sspa associate with rna polymerase (rnap) in f. tularensis, and that sspa is required for mgla to associate with rnap. fur ... | 2007 | 17571921 |
| proteomic analysis of antibody response in a case of laboratory-acquired infection with francisella tularensis subsp. tularensis. | immunoproteomic analysis was applied to study the immunoreactivity of serum samples collected at different time points from a laboratory assistant accidentally infected with highly virulent strain of francisella tularensis subsp. tularensis. immunoblotting showed that the spectrum of f. tularensis antigens recognized specifically by immune sera remained with the exception for 1 antigen stable for up to 16 years after infection. using immunoproteomics approach 10 immunoreactive antigens were succ ... | 2007 | 17575919 |
| tularemia presenting with tonsillopharyngitis and cervical lymphadenitis: report of two cases. | tularemia is a zoonotic disease caused by francisella tularensis. francisella tularensis is transmitted to humans by direct contact or ingestion of infected animal tissues, through the bite of infected arthropods, by consumption of contaminated food or water, or from inhalation of aerolized bacteria. in this report we describe 2 cases with oropharyngeal tularemia who presented with tonsillopharyngitis and cervical lymphadenitis. | 2007 | 17577830 |
| prophylactic and therapeutic use of antibodies for protection against respiratory infection with francisella tularensis. | the role of abs in protection against respiratory infection with the intracellular bacterium francisella tularensis is not clear. to investigate the ability of abs to clear bacteria from the lungs and prevent systemic spread, immune serum was passively administered i.p. to naive mice before intranasal f. tularensis live vaccine strain infection. it was found that immune serum treatment provided 100% protection against lethal challenge while normal serum or ig-depleted immune serum provided no pr ... | 2007 | 17579074 |
| outbreaks of tularemia in turkey. | tularemia, casued by francisella tularensis, is a zoonotic disease presenting various clinical forms. in the present study, three outbreaks of tularemia occurred from january to march and september in 2004 (first and second) and january to march in 2005 (third) are reported from the north-eastern part of turkey. all cases originated from the same geographical location. in total, 56 patients having complaints of fever, malaise, chills and shivering, painful sore throat with swollen tonsils and en ... | 2007 | 17579300 |
| from rabbits to humans: the contributions of dr. theodore e. woodward to tularemia research. | tularemia is an endemic zoonotic infection caused by francisella tularensis, which primarily causes infection in humans who have handled contaminated animal tissue or have been bitten by infected arthropods. because of its ease of dispersion and transmission and its high degree of infectivity, f. tularensis is also considered to be a bioterrorism agent. consequently, there is renewed interest in the development of safe, effective measures, such as vaccines, to prevent the morbidity and mortality ... | 2007 | 17582573 |
| a full-genomic sequence-verified protein-coding gene collection for francisella tularensis. | the rapid development of new technologies for the high throughput (ht) study of proteins has increased the demand for comprehensive plasmid clone resources that support protein expression. these clones must be full-length, sequence-verified and in a flexible format. the generation of these resources requires automated pipelines supported by software management systems. although the availability of clone resources is growing, current collections are either not complete or not fully sequence-verif ... | 2007 | 17593976 |
| [genotypic heterogeneity and geographic diversity of collection strains of francisella tularensis as determined using the vntr variability analysis and dna sequencing]. | the analysis of the identification genotypes allowed the strains to be grouped into 61 variants from a to i with the incidence rate 0.002-0.142. the cluster analysis of the identification genotypes allowed the strains to be grouped into 9 clusters with different number of components. actual existence of genotypic heterogeneity and geographic diversity of the f. tularensis strains was demonstrated in addition to territorial attribution of certain strains. the geoinformation system tularemia was d ... | 2007 | 17600922 |
| new species in the genus francisella (gammaproteobacteria; francisellaceae); francisella piscicida sp. nov. isolated from cod (gadus morhua). | a francisella strain, gm2212, previously isolated from moribund farmed atlantic cod (gadus morhua) in norway, is closely related to francisella philomiragia among francisella spp. according to its complete 16s rdna, 16s-23s intergenic spacer, 23s rdna, 23s-5s intergenic spacer, 5s rdna, fopa, lipoprotein tul4 (lpna), malate dehydrogenase and hypothetical lipoprotein (lpnb) sequences. a comparison between gm2212 and the type strain of francisella philomiragia were performed by dna-dna hybridizati ... | 2007 | 17619856 |
| q fever community-acquired pneumonia in a patient with crohn's disease on immunosuppressive therapy. | community-acquired pneumonia (cap) may be caused by typical or atypical pathogens. the three most common zoonotic atypical pathogens are chlamydophila psittaci (psittacosis), francisella tularensis (tularemia), and coxiella burnetii (q fever). atypical caps are suggested by a distinctive pattern of extrapulmonary organ involvement. zoonotic cap may be differentiated from nonzoonotic cap (chlamydia pneumoniae, mycoplasma pneumoniae, legionnaire's disease) by a recent zoonotic vector contact histo ... | 2007 | 17628200 |
| differential effects of francisella tularensis lipopolysaccharide on b lymphocytes. | francisella tularensis, a designated category a biological agent, can cause severe infection in humans. previous studies have demonstrated a significant immunoprotective role for b lymphocytes in animal models, but the responses of human b lymphocytes to f. tularensis components are largely unknown. the lps of f. tularensis is atypical and has been reported to lack biological activity on myeloid cells and mouse b cells. our study characterized the immunological effects of highly purified lps fro ... | 2007 | 17634278 |
| identification of francisella sp. from atlantic salmon, salmo salar l., in chile. | 2007 | 17640254 | |
| mgla regulates francisella tularensis subsp. novicida (francisella novicida) response to starvation and oxidative stress. | mgla is a transcriptional regulator of genes that contribute to the virulence of francisella tularensis, a highly infectious pathogen and the causative agent of tularemia. this study used a label-free shotgun proteomics method to determine the f. tularensis subsp. novicida (f. novicida) proteins that are regulated by mgla. the differences in relative protein amounts between wild-type f. novicida and the mgla mutant were derived directly from the average peptide precursor ion intensity values mea ... | 2007 | 17644593 |