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francisella tularensis in rodents, china.a total of 420 rodents in china were examined for francisella tularensis by polymerase chain reaction. the infection rates were 4.76% in total, and 11.65%, 10.00%, 6.56%, 1.77%, and 0% in jilin, xinjiang, heilongjiang, inner mongolia, and zhejiang, respectively. sequence analysis showed that all the detected agents belonged to f. tularensis subsp. holarctica.200616707060
raccoons and skunks as sentinels for enzootic tularemia.we analyzed sera from diverse mammals of martha's vineyard, massachusetts, for evidence of francisella tularensis exposure. skunks and raccoons were frequently seroreactive, whereas white-footed mice, cottontail rabbits, deer, rats, and dogs were not. tularemia surveillance may be facilitated by focusing on skunks and raccoons.200616707067
characterization of the siderophore of francisella tularensis and role of fsla in siderophore production.we determined that lvs and schu s4 strains of the human pathogen francisella tularensis express a siderophore when grown under iron-limiting conditions. we purified this siderophore by conventional column chromatography and high-pressure liquid chromatography and used mass spectrometric analysis to demonstrate that it is structurally similar to the polycarboxylate siderophore rhizoferrin. the siderophore promoted the growth of lvs and schu s4 strains in iron-limiting media. we identified a poten ...200616707671
immunologic consequences of francisella tularensis live vaccine strain infection: role of the innate immune response in infection and immunity.francisella tularensis (ft), a gram-negative intracellular bacterium, is the etiologic agent of tularemia. although attenuated for humans, i.p. infection of mice with <10 ft live vaccine strain (lvs) organisms causes lethal infection that resembles human tularemia, whereas the ld50 for an intradermal infection is >10(6) organisms. to examine the immunological consequences of ft lvs infection on the innate immune response, the inflammatory responses of mice infected i.p. or intradermally were com ...200616709849
basis for the failure of francisella tularensis lipopolysaccharide to prime human polymorphonuclear leukocytes.francisella tularensis is the intracellular gram-negative coccobacillus that causes tularemia, and its virulence and infectiousness make it a potential agent of bioterrorism. previous studies using mononuclear leukocytes have shown that the lipopolysaccharide (lps) of f. tularensis is neither a typical proinflammatory endotoxin nor an endotoxin antagonist. this inertness suggests that f. tularensis lps does not bind host lps-sensing molecules such as lps-binding protein (lbp). using priming of t ...200616714555
toll-like receptor 2 is required for control of pulmonary infection with francisella tularensis.toll-like receptor 2 (tlr2) deficiency enhances murine susceptibility to infection by francisella tularensis as indicated by accelerated mortality, higher bacterial burden, and greater histopathology. analysis of pulmonary cytokine levels revealed that tlr2 deficiency results in significantly lower levels of tumor necrosis factor alpha and interleukin-6 but increased amounts of gamma interferon and monocyte chemoattractant protein 1. this pattern of cytokine production may contribute to the exag ...200616714598
louse-borne bacterial pathogens in lice (phthiraptera) of rodents and cattle from egypt.we collected 1,023 lice, representing 5 species, from rats and domestic cattle throughout 13 governorates in egypt and tested these lice for anaplasma marginale, bartonella spp., brucella spp., borrelia recurrentis, coxiella burnetii, francisella tularensis, and rickettsia spp. by pcr amplification and sequencing. five different louse-borne bacterial agents were detected in lice from rodents or cattle, including "bartonella rattimassiliensis", "b. phoceensis", and bartonella sp. near bartonella ...200616729688
in vivo proteomic analysis of the intracellular bacterial pathogen, francisella tularensis, isolated from mouse spleen.understanding the pathogenesis of infectious diseases requires comprehensive knowledge of the proteins expressed by the pathogen during in vivo growth in the host. proteomics provides the tools for such analyses but the protocols required to purify sufficient quantities of the pathogen from the host organism are currently lacking. here, we present a rapid immunomagnetic protocol for the separation of francisella tularensis, a highly virulent bacterium and potential biowarfare agent, from the spl ...200616730660
characterization of the lipopolysaccharide and beta-glucan of the fish pathogen francisella victoria.lipopolysaccharide (lps) and beta-glucan from francisella victoria, a fish pathogen and close relative of highly virulent mammal pathogen francisella tularensis, have been analyzed using chemical and spectroscopy methods. the polysaccharide part of the lps was found to contain a nonrepetitive sequence of 20 monosaccharides as well as alanine, 3-aminobutyric acid, and a novel branched amino acid, thus confirming f. victoria as a unique species. the structure identified composes the largest oligos ...200616759227
tularemia: current epidemiology and disease management. 200616762740
immunoproteomic analysis of the murine antibody response to successful and failed immunization with live anti-francisella vaccines.francisella tularensis subspecies tularensis is one of the most virulent of bacterial pathogens for humans. protective immunity against the pathogen can be induced in humans and some, but not all, mouse strains by vaccination with live, but not killed, vaccines. in mice, this protection is mediated predominantly by cd4+ and cd8+ t cells. this is thought to be the case too for humans. nevertheless, it is possible that successful vaccination elicits antigen-specific antibodies that can serve as co ...200616781667
identification, recombinant expression, immunolocalization in macrophages, and t-cell responsiveness of the major extracellular proteins of francisella tularensis.a safer and more effective vaccine than the previously developed live attenuated vaccine is needed for combating francisella tularensis, a highly infectious bacterial pathogen. to search for potential candidates for inclusion in a new vaccine, we characterized the proteins present in the culture filtrates of a virulent recent clinical isolate and the attenuated live vaccine strain of f. tularensis using a proteomic approach. we identified a total of 12 proteins; among these, catalase-peroxidase ...200616790773
identification of francisella tularensis genes affected by iron limitation.cells of an attenuated live vaccine strain (lvs) of f. tularensis grown under iron-restricted conditions were found to contain increased quantities of several proteins relative to cells of this same strain grown under iron-replete conditions. mass spectrometric analysis identified two of these proteins as iglc and pdpb, both of which are encoded by genes located in a previously identified pathogenicity island in f. tularensis lvs. regions with homology to the consensus fur box sequence were loca ...200616790797
differential infection of mononuclear phagocytes by francisella tularensis: role of the macrophage mannose receptor.francisella tularensis (ft) is a gram-negative bacterium and the causative agent of tularemia. it is well established that this organism replicates inside macrophages, but we are only beginning to understand this interface at the molecular level. herein, we compared directly the ability of ft subspecies holarctica live-vaccine strain to infect freshly isolated human peripheral blood monocytes, monocyte-derived macrophages (mdm), and cells of the murine macrophage cell line j774a.1 (j774). we now ...200616816147
population structure of francisella tularensis.we have sequenced fragments of five metabolic housekeeping genes and two genes encoding outer membrane proteins from 81 isolates of francisella tularensis, representing all four subspecies. phylogenetic clustering of gene sequences from f. tularensis subsp. tularensis and f. tularensis subsp. holarctica aligned well with subspecies affiliations. in contrast, f. tularensis subsp. novicida and f. tularensis subsp. mediasiatica were indicated to be phylogenetically incoherent taxa. incongruent gene ...200616816208
transcriptional profiling of the peripheral blood response during tularemia.tularemia is a febrile disease caused by the highly contagious bacterium francisella tularensis. we undertook an analysis of the transcriptional response in peripheral blood during the course of ulceroglandular tularemia by use of affymetrix microarrays comprising 14,500 genes. samples were obtained from seven individuals at five occasions during 2 weeks after the first hospital visit and convalescent samples 3 months later. in total, 265 genes were differentially expressed, 95 of which at more ...200616826236
[vntr-genotyping of francisella tularensis strains isolated in the former ussr territory and some european countries during epizootics in 1988 - 1989].retrospective vntr-analysis of 159 francisella tularensis subsp. holarctica strains isolated in december 1988 - february 1989 in former ussr and some european countries was carried out. analysis of heterogenic genotypes of strains allow to subdivide them into 30 groups of variants by individual genotypes, while cluster analysis--to subdivide them in 7 clusters with different number of compositions. the predominance of genotype c1 strains isolated on the rostov and archangelsk regions and the cri ...200616830584
epidemiologic and molecular analysis of human tularemia, united states, 1964-2004.tularemia in the united states is caused by 2 subspecies of francisella tularensis, subspecies tularensis (type a) and subspecies holarctica (type b). we compared clinical and demographic features of human tularemia cases from 1964 to 2004 from 39 states in which an isolate was recovered and subtyped. our data indicate that type a and type b infections differ with respect to affected populations, anatomic site of isolation, and geographic distribution. molecular subtyping with pulsed-field gel e ...200616836829
the bla2 beta-lactamase from the live-vaccine strain of francisella tularensis encodes a functional protein that is only active against penicillin-class beta-lactam antibiotics.francisella tularensis ssp. tularensis is a category a select agent and the causal organism for the zoonotic disease tularemia. the vast majority of f. tularensis isolates are beta-lactamase-positive. beta-lactamase production is widely believed to be responsible for the inefficacy of beta-lactams in the treatment of tularemia. in this study, we report the cloning and characterization of the two chromosomally encoded f. tularensis ssp. holarctica live-vaccine strain (lvs) beta-lactamases. the tw ...200616841206
tularemia as a cause of fever in a squirrel monkey.a 3-year-old female squirrel monkey (saimiri sciureus sciureus) was examined because of sudden onset of lethargy and fever.200616842053
macrophage pro-inflammatory response to francisella novicida infection is regulated by ship.francisella tularensis, a gram-negative facultative intracellular pathogen infecting principally macrophages and monocytes, is the etiological agent of tularemia. macrophage responses to f. tularensis infection include the production of pro-inflammatory cytokines such as interleukin (il)-12, which is critical for immunity against infection. molecular mechanisms regulating production of these inflammatory mediators are poorly understood. herein we report that the sh2 domain-containing inositol ph ...200616848641
a microarray analysis of the murine macrophage response to infection with francisella tularensis lvs.the response of cells of the mouse macrophage cell line j774 to infection with francisella tularensis lvs was analysed by means of a dna microarray representing approximately 18,500 genes (20,600 clones). the adaptive response was modest at all time points, and at most, 81 clones were differentially regulated from the time point of uptake of bacteria (0 min) up to 240 min later. for all five time points, 229 clones fulfilled the criteria of being differentially regulated, i.e. the ratio between ...200616849722
critical role for serum opsonins and complement receptors cr3 (cd11b/cd18) and cr4 (cd11c/cd18) in phagocytosis of francisella tularensis by human dendritic cells (dc): uptake of francisella leads to activation of immature dc and intracellular survival of the bacteria.francisella tularensis is one of the most infectious human pathogens known. although much has been learned about the immune response of mice using an attenuated live vaccine strain (lvs) derived from f. tularensis subspecies holarctica (type b), little is known about the responses of human monocyte-derived immature dendritic cells (dc). here, we show that optimal phagocytosis of lvs by dc is dependent on serum opsonization. we demonstrate that complement factor c3-derived opsonins and the major ...200616857732
host usage and seasonal activity patterns of ixodes kingi and i. sculptus (acari: ixodidae) nymphs in a colorado prairie landscape, with a summary of published north american host records for all life stages.we examined host usage and seasonal activity patterns of the nymphal stage of the ticks ixodes kingi and i. sculptus within a prairie rodent community in north-central colorado. ixodes kingi was commonly encountered on both northern grasshopper mice (onychomys leucogaster) and thirteen-lined ground squirrels (spermophilus tridecemlineatus), whereas i. sculptus frequently infested s. tridecemlineatus but was absent from o. leucogaster. low numbers of ticks of both species were collected from deer ...200616859106
construction and characterization of an attenuated purine auxotroph in a francisella tularensis live vaccine strain.francisella tularensis is a facultative intracellular pathogen and is the etiological agent of tularemia. it is capable of escaping from the phagosome, replicating to high numbers in the cytosol, and inducing apoptosis in macrophages of a variety of hosts. f. tularensis has received significant attention recently due to its potential use as a bioweapon. currently, there is no licensed vaccine against f. tularensis, although a partially protective live vaccine strain (lvs) that is attenuated in h ...200616861631
virulence of francisella spp. in chicken embryos.we examined the utility of infecting chicken embryos as a means of evaluating the virulence of different francisella sp. strains and mutants. infection of 7-day-old chicken embryos with a low dose of f. novicida or f. tularensis subsp. holarctica live vaccine strain (lvs) resulted in sustained growth for 6 days. different doses of these two organisms were used to inoculate chicken embryos to determine the time to death. these experiments showed that wild-type f. novicida was at least 10,000-fold ...200616861669
identification of transposon insertion mutants of francisella tularensis tularensis strain schu s4 deficient in intracellular replication in the hepatic cell line hepg2.francisella tularensis is a zoonotic intracellular bacterial pathogen that causes tularemia. the subspecies tularensis is highly virulent and is classified as a category a agent of biological warfare because of its low infectious dose by an aerosol route, and its ability to cause severe disease. in macrophages f. tularensis exhibits a rather novel intracellular lifestyle; after invasion it remains in a phagosome for three to six hours before escaping to, and replicating in the cytoplasm. the mol ...200616879747
uptake of serum-opsonized francisella tularensis by macrophages can be mediated by class a scavenger receptors.the bacterium francisella tularensis is highly infective, and this is one of the chief attributes that has led to its development as a bioweapon. establishment of infection requires efficient uptake of f. tularensis by host macrophages, which provide a safe in vivo environment for f. tularensis replication. little is known, however, about the cellular entry mechanisms employed by this organism. this report shows that efficient uptake of f. tularensis live vaccine strain (lvs) by macrophages is d ...200616882038
paired-end sequence mapping detects extensive genomic rearrangement and translocation during divergence of francisella tularensis subsp. tularensis and francisella tularensis subsp. holarctica populations.comparative genome hybridization of the francisella tularensis subsp. tularensis and f. tularensis subsp. holarctica populations have shown that genome content is highly conserved, with relatively few genes in the f. tularensis subsp. tularensis genome being absent in other f. tularensis subspecies. to determine if organization of the genome differs between global populations of f. tularensis subsp. tularensis and f. tularensis subsp. holarctica, we have used paired-end sequence mapping (pesm) t ...200616885459
real-time pcr for francisella tularensis types a and b. 200617283646
[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 ...200617290906
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 ...200617186960
[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 ...200617249186
[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 ...200617340995
[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 ...200617357677
aquatic francisella-like bacterium associated with mortality of intensively cultured hybrid striped bass morone chrysops x m. saxatilis.the present study identifies an emerging disease associated with an aquatic francisella-like bacterium that can cause mortality in hybrid striped bass morone chrysops x m. saxatilis reared intensively in freshwater. clinically affected fish were lethargic, had scattered haemorrhagic cutaneous lesions and diffuse gill pallor. the head kidney and spleen were markedly swollen and contained numerous interstitial granulomas; histological examination revealed small, pleomorphic gram-negative coccobaci ...200617140136
characterization of recombinant francisella tularensis acid phosphatase a.francisella tularensis is the etiologic agent of the potentially fatal human disease tularemia and is capable of survival and multiplication within professional phagocytes of the host. while the mechanisms that allow intracellular survival of the bacterium are only now beginning to be elucidated at the molecular level, previous work demonstrated that f. tularensis produces copious levels of an acid phosphatase which in crude and purified form affected the dose-dependent abrogation of the respira ...200615964202
grey variants of the live vaccine strain of francisella tularensis lack lipopolysaccharide o-antigen, show reduced ability to survive in macrophages and do not induce protective immunity in mice.francisella tularensis live vaccine strain (lvs) produces two colony types when grown on solid media, often referred to as blue variants (bv) and grey variants (gv). whereas blue variant bacteria possessed a lipopolysaccharide o-side chain, grey variant bacteria lacked o-side chains. grey variant bacteria appeared in stationary phase bacterial cultures and could be identified using a novel facs-based assay. compared to blue variant bacteria, grey variants showed a reduced ability to infect and s ...200616257097
intracellular survival mechanisms of francisella tularensis, a stealth pathogen.research on the highly virulent and contagious, facultative intracellular bacterium francisella tularensis has come into the limelight recently, but still little is known regarding its virulence mechanisms. this review summarizes recent studies on its intramacrophage survival mechanisms, some of which appear to be novel.200616239121
francisella tularensis travels a novel, twisted road within macrophages.francisella tularensis is a highly infectious intracellular bacterium that causes fulminating disease and is a potential bioweapon. although entry of the bacteria into macrophages is mediated by novel asymmetric, spacious pseudopod loops, the nascent phagosome becomes tight fitting within seconds of formation. biogenesis of the francisella-containing phagosome (fcp) is arrested for 2-4h at a unique stage within the endosomal-lysosomal degradation pathway, followed by gradual bacterial escape int ...200616356719
internalization and phagosome escape required for francisella to induce human monocyte il-1beta processing and release.macrophage responses to francisella infection have been characterized previously by subdued proinflammatory responses; however, these studies have generally focused on macrophage cell lines or monocyte-derived macrophages. therefore, we studied the ability of fresh human blood monocytes to engulf and respond to francisella by using the live vaccine strain variant and francisella novicida. because francisella organisms have been reported to escape from the phagolysosome into the cytosol, we hypot ...200616373510
h2bc: a new technique for nmr analysis of complex carbohydrates.it is demonstrated that the h2bc nmr pulse sequence (j. am. chem. soc.2005, 127, 6154, magn. reson. chem.2005, 43, 971-974) offers unambiguous assignments and significant simplification of nmr spectra of large and complex carbohydrates compared to other techniques for the establishment of correlations over more than one bond. h2bc almost exclusively correlates protons and proton-bearing carbon spins separated by two covalent bonds and is independent of occasionally vanishing (2)j(ch) coupling co ...200616406276
cryopyrin activates the inflammasome in response to toxins and atp.a crucial part of the innate immune response is the assembly of the inflammasome, a cytosolic complex of proteins that activates caspase-1 to process the proinflammatory cytokines interleukin (il)-1beta and il-18. the adaptor protein asc is essential for inflammasome function, binding directly to caspase-1 (refs 3, 4), but the triggers of this interaction are less clear. asc also interacts with the adaptor cryopyrin (also known as nalp3 or cias1). activating mutations in cryopyrin are associated ...200616407890
bacterial cell microarrays for the detection and characterization of antibodies against surface antigens.bacterial cell surface antigens interact with the host immune system resulting in the production of antibodies. detection of antibodies against surface antigens has applications in diagnosis of many bacterial infections, assessment of immune status and epidemiological studies. we developed a microarray platform, for antibody detection, by printing gram-negative and gram-positive whole bacterial cells on nitrocellulose coated glass substrates. antibody binding was detected using fluorophore label ...200616423364
detection of biological threat agents by real-time pcr: comparison of assay performance on the r.a.p.i.d., the lightcycler, and the smart cycler platforms.rapid detection of biological threat agents is critical for timely therapeutic administration. fluorogenic pcr provides a rapid, sensitive, and specific tool for molecular identification of these agents. we compared the performance of assays for 7 biological threat agents on the idaho technology, inc. r.a.p.i.d., the roche lightcycler, and the cepheid smart cycler.200616391330
virulence comparison in mice of distinct isolates of type a francisella tularensis.francisella tularensis subspecies tularensis (type a f. tularensis) is considered to be one of the most virulent of all bacterial pathogens. mice are extremely susceptible to infection with this subspecies (ld100 via various inoculation routes is <10 cfu). however, it has not been established whether overt virulence differences exist amongst type a strains of f. tularensis. to this end, the present study compared the virulence of two distinct type a strains, fsc033 and schu s4, for naïve mice an ...200616448801
expression cloning and periplasmic orientation of the francisella novicida lipid a 4'-phosphatase lpxf.francisella tularensis and related intracellular pathogens synthesize lipid a molecules that differ from their escherichia coli counterparts. although a functional orthologue of lpxk, the gene encoding the lipid a 4'-kinase, is present in francisella, no 4'-phosphate moiety is attached to francisella lipid a. we now demonstrate that a membrane-bound phosphatase present in francisella novicida u112 selectively removes the 4'-phosphate residue from tetra- and pentaacylated lipid a molecules. a clo ...200616467300
transcriptional profiling of host responses in mouse lungs following aerosol infection with type a francisella tularensis.tularaemia caused by inhalation of type a francisella tularensis bacteria is one of the most aggressive infectious diseases known, but the reasons for the very rapid spread of the organism from the lungs to internal organs and the ensuing mortality are unknown. the present study used the mouse model to examine in detail the host immune response in the lung. after an aerosol challenge with 20 c.f.u. of the type a strain fsc033, all mice developed clinical signs of severe disease, showed weight lo ...200616476789
fiber-optic microsphere-based arrays for multiplexed biological warfare agent detection.we report a multiplexed high-density dna array capable of rapid, sensitive, and reliable identification of potential biological warfare agents. an optical fiber bundle containing 6000 individual 3.1-mum-diameter fibers was chemically etched to yield microwells and used as the substrate for the array. eighteen different 50-mer single-stranded dna probes were covalently attached to 3.1-mum microspheres. probe sequences were designed for bacillus anthracis, yersinia pestis, francisella tularensis, ...200616478092
the identification and evaluation of atp binding cassette systems in the intracellular bacterium francisella tularensis.francisella tularensis is a facultative intracellular bacterium responsible for the disease tularemia. analysis of the fully sequenced genome of the virulent f. tularensis strain schu s4 has led to the identification of twenty atp binding cassette (abc) systems, of which five appear to be non-functional. the fifteen complete systems comprise three importers, five exporters, four systems involved in non-transport processes, and three systems of unknown or ill-defined function. the number and clas ...200616503121
antibiotic selection and resistance issues with fluoroquinolones and doxycycline against bioterrorism agents.bacillus anthracis (anthrax), yersinia pestis (plague), francisella tularensis (tularemia), coxiella burnetti (q fever), and brucella sp (brucellosis) are all potential bioterrorism agents. their known virulence, potential lethality, and ability to develop resistance to known antibiotic treatments make these pathogens particularly dangerous. we reviewed the scientific literature by searching medline databases and published abstracts from the interscience conference on antimicrobial agents and ch ...200616506347
crystallization of a newly discovered histidine acid phosphatase from francisella tularensis.francisella tularensis is a highly infectious bacterial pathogen that is considered by the centers for disease control and prevention to be a potential bioterrorism weapon. here, the crystallization of a 37.2 kda phosphatase encoded by the genome of f. tularensis subsp. holarctica live vaccine strain is reported. this enzyme shares 41% amino-acid sequence identity with legionella pneumophila major acid phosphatase and contains the rhgxrxp motif that is characteristic of the histidine acid phosph ...200616511256
francisella tularensis in the united states.the causative agent of tularemia, francisella tularensis, is a formidable biologic agent that occurs naturally throughout north america. we examined genetic and spatial diversity patterns among 161 us f. tularensis isolates by using a 24-marker multiple-locus variable-number tandem repeat analysis (mlva) system. mlva identified 126 unique genotypes. phylogenetic analyses showed patterns similar to recently reported global-scale analyses. we observed clustering by subspecies, low genetic diversit ...200516485467
serologic survey of select infectious diseases in coyotes and raccoons in nebraska.to obtain data about select zoonotic and other infectious diseases in free-ranging predators in five ecoregions in nebraska, sera were collected from 67 coyotes (canis latrans) and 63 raccoons (procyon lotor) from november 2002 through january 2003. for coyotes, antibodies were detected against canine distemper virus (cdv, 61%), francisella tularensis (32%), rickettsia rickettsi (13%), and flaviviruses (48%). none of the coyote sera had antibodies to borrelia burgdorferi, brucella canis, or six ...200516456169
[incidence of zoonoses in petting zoos and evaluation of hygiene measures to prevent the transmission to humans].in summer 2003, a study was performed in thirty swiss petting zoos with the objective to determine the prevalence of zoonotic agents, and to describe hygiene measures implemented to reduce the risk of human infection. fecal samples from different animal species were collected from the floor of pens to determine the prevalence of salmonella spp., campylobacter spp., verocytotoxin producing e. coli/ vtec and francisella tularensis. a questionnaire on hygiene measures, number of animals per species ...200516398191
[rickettsia helvetica: an emerging tick-borne pathogen in hungary and europe].rickettsia helvetica belonging to spotted fever group rickettsiae was recently detected by polymerase chain reaction followed by sequencing in european sheep ticks (ixodes ricinus) from hungary. current knowledge on these rickettsiae and the clinical and diagnostic aspects of r. helvetica infection is summarized. in acute cases, r. helvetica is generally responsible for flu-like symptoms. nevertheless, recent data indicate that in chronic cases, these rickettsiae can be responsible for perimyoca ...200516440500
natural killer and cd8 t cells dominate the response by human peripheral blood mononuclear cells to inactivated francisella tularensis live vaccine strain.francisella tularensis is a category a biothreat agent, and as a result, it has recently generated much research interest. f. tularensis live vaccine strain (lvs) is an attenuated form of the virulent f. tularensis organism and has previously been used as a vaccine. however, because of safety concerns, it is no longer approved for this purpose. thus, the use of inactivated organisms is preferable for vaccine purposes. although many studies have been performed that examine human peripheral blood ...200516386645
seroprevalence of brucellosis, tularemia, and yersiniosis in wild boars (sus scrofa) from north-eastern germany.brucellosis and tularemia are classical zoonotic diseases transmitted from an animal reservoir to humans. both, wildlife and domestic animals, contribute to the spreading of these zoonoses. the surveillance of the animal health status is strictly regulated for domestic animals, whereas systematic disease monitoring in wildlife does not exist. the aim of the present study was to provide data on the prevalence of anti-brucella, anti-francisella and anti-yersinia antibodies in wild boars from north ...200516364020
[the interaction of dynamic speckles with suspensions of gram-negative cells].the role of temporal coherence at photodynamic action of light on living cells was investigated. a mathematical model describing the interaction of low-coherent speckles with bacterial cells was suggested and its parameters were determined based on experimental data. the interrelation between the life time of dynamic optical speckles and the degree of photodestruction of illuminated cells was established by computer simulations. the conditions were determined under which the photoinactivation of ...200516248164
aerosol-, but not intradermal-immunization with the live vaccine strain of francisella tularensis protects mice against subsequent aerosol challenge with a highly virulent type a strain of the pathogen by an alphabeta t cell- and interferon gamma- dependent mechanism.francisella tularensis is an extremely virulent facultative intracellular bacterial pathogen of many mammalian species including mice and humans in which it causes a spectrum of disease collectively called tularemia. in humans, intradermal or inhaled inocula of 10cfu or less of the most virulent strains of the pathogen are sufficient to cause severe infection and possible death; in mice similar inocula are routinely lethal. an attenuated live vaccine strain, f. tularensis lvs, was developed almo ...200515752834
the live vaccine strain of francisella tularensis replicates in human and murine macrophages but induces only the human cells to secrete proinflammatory cytokines.francisella tularensis is the highly infectious agent of tularemia, a disease that can prove fatal in humans. an attenuated live vaccine strain (lvs) of this bacterium is avirulent in man but produces lethal illness in mice. as a step toward understanding the species specificity of the lvs, we compared its interactions with murine and human leukocytes. the bacterium replicated within murine bone marrow-derived macrophages (mubmdm), human monocyte-derived macrophages (humdm), and freshly isolated ...200515758077
low dose aerosol infection of mice with virulent type a francisella tularensis induces severe thymus atrophy and cd4+cd8+ thymocyte depletion.francisella tularensis is a gram-negative facultative intracellular bacterium and the causative agent of tularemia. two subspecies (type a and b strains) of the pathogen exist, the former being much more virulent than the latter for humans and other higher mammals. in this study, we examined the effect of virulent strains of f. tularensis infection on the thymus and thymocytes and the potential mechanisms involved. low-dose aerosol exposure of c57bl/6 mice with type a, but not type b, f. tularen ...200516257504
discrimination between francisella tularensis and francisella-like endosymbionts when screening ticks by pcr.the presence of francisella-like endosymbionts in tick species known to transmit tularemia poses a potential diagnostic problem for laboratories that screen tick samples by pcr for francisella tularensis. tick samples initially considered positive for f. tularensis based on standard 16s rrna gene pcr were found to be positive only for francisella-like endosymbionts using a multitarget f. tularensis taqman assay (isftu2, tul4, and iglc) and 16s rrna gene sequencing. specificity of pcr-based diagn ...200516269811
francisella tularensis induces aberrant activation of pulmonary dendritic cells.francisella tularensis is an obligate intracellular bacterium that induces severe, acute, often fatal disease when acquired by the respiratory route. despite the seriousness of this pathogen, very little is understood about its interaction with key target cells in the airways and lungs (alveolar macrophages and airway dendritic cells (dc)) after inhalation. in this study we demonstrate replication of f. tularensis in primary dc. early after infection, f. tularensis induced increased expression o ...200516272336
[rodents as the vectors of infective agents in the natural foci of infections in the moscow megapolis].this work deals with the results of 40-year observations on the circulation of infective agents in the natural foci of infections (tularemia, leptospirosis, hemorrhagic fever with renal syndrome) among rodents and other small mammals in the territory of the moscow. the monitoring of their frequency and the infection rates remains the main effective measure for the prophylaxis of dangerous infections among the population of the megapolis.200516279545
[bioterrorism].biological terrorism is intentionally to use infectious substances for developing diseases or death in animals or humans, leading to disaster and panic in our community. bioterrorism-associated diseases are mostly rare or eradicated infectious diseases, and recently, we do not have experience to make a clinical and laboratory diagnosis. in particular, these infectious diseases have incubation periods from infection to development of the disease. the staff working at public health institutions, i ...200516296383
a 12-case outbreak of pharyngeal plague following the consumption of camel meat, in north-eastern jordan.between late january and early february 1997, an outbreak of plague, associated with cervical lymphadenopathy and fever, occurred in the jordanian village of azraq ad-druze, which lies about 50 km west of the border with saudi arabia. the 12 cases who presented at hospital were initially assumed to have tularaemia, and all were successfully treated with gentamicin. when, however, their sera were tested for evidence of yersinia pestis or francisella tularensis infection (using haemagglutination, ...200516297292
a mutant of francisella tularensis strain schu s4 lacking the ability to express a 58-kilodalton protein is attenuated for virulence and is an effective live vaccine.francisella tularensis subsp. tularensis (type a) strain schu s4 is a prototypic strain of the pathogen that is highly virulent for humans and other mammals. its intradermal (i.d.) 50% lethal dose (ld50) for mice is <10 cfu. we discovered a spontaneous mutant, designated fsc043, of schu s4 with an i.d. ld50 of >10(8) cfu. fsc043 effectively vaccinated mice against challenge with a highly virulent type a strain, and the protective efficacy was at least as good as that of f. tularensis lvs, an emp ...200516299332
clinical use of a diagnostic pcr for francisella tularensis in patients with suspected ulceroglandular tularaemia.a retrospective analysis to evaluate the clinical use of a diagnostic pcr for francisella tularensis in patients with suspected ulceroglandular tularaemia was performed. 154 samples, 129 from patients with definitive tularaemia and 25 from patients where tularaemia could be ruled out, were analysed. the diagnostic pcr had a specificity of 96%, a sensitivity of 78.3%, and a positive predictive value of 99%. especially samples from encrusted lesions, even up to 4 weeks old, in patients with tulara ...200516308216
the phagosomal transporter a couples threonine acquisition to differentiation and replication of legionella pneumophila in macrophages.differentiation in response to environmental cues is integral to the success of many intracellular pathogens. by characterizing a legionella pneumophila mutant defective for differentiation in broth and replication in macrophages, we identified a subfamily of major facilitator superfamily transporters, here named pht (phagosomal transporter), that also is conserved in two other vacuolar pathogens, coxiella burnetii and francisella tularensis. biolog phenotype microarray analysis indicated that p ...200515998735
cd4-cd8- t cells control intracellular bacterial infections both in vitro and in vivo.memory t cells, including the well-known cd4(+) and cd8(+) t cells, are central components of the acquired immune system and are the basis for successful vaccination. after infection, cd4(+) and cd8(+) t cells expand into effector cells, and then differentiate into long-lived memory cells. we show that a rare population of cd4(-)cd8(-)cd3(+)alphabeta(+)gammadelta(-)nk1.1(-) t cells has similar functions. these cells potently and specifically inhibit the growth of the intracellular bacteria mycob ...200516027239
[influence of cycloferon on the biological properties of bacterial intracellular pathogens].the influence of cycloferon on some biological properties of pathogenic (shigella spp., salmonella spp., francisella tularensis, brucella spp.) and opportunistic (escherichia coli, staphylococcus spp.) microorganisms has been experimentally determined in vitro. as revealed in these experiments, the preparation used at concentrations under study considerably suppresses the antilysozyme and anticomplementary activity of gram-negative intracellular parasites (shigellae, salmonellae, f. tularensis, ...200516028504
prevalence of infection with francisella tularensis, borrelia burgdorferi sensu lato and anaplasma phagocytophilum in rodents from an endemic focus of tularemia in bulgaria.the prevalence of francisella tularensis, borrelia burgdorferi and anaplasma phagocytophilum in rodents is a determinant for their role in maintaining pathogens in the environment. a total of 169 rodents, trapped in an endemic focus of tularemia, were examined by pcr to asses the frequency of infection with the etiological agents of tularemia, lyme borreliosis and human granulocytic anaplasmosis. the overall prevalence of f. tularensis was 22 %. in 6 % of the black rats, f. tularensis was identi ...200516028881
a novel screening elisa and a confirmatory western blot useful for diagnosis and epidemiological studies of tularemia.a novel enzyme-linked immunosorbent assay (elisa) and a confirmatory western blot (wb) to detect human antibodies against francisella tularensis were evaluated. the elisa was based on partially purified lipopolysaccharide (lps), the wb on whole antigen of f. tularensis. positive wb showed a typical lps ladder. sensitivity and specificity of the elisa, as assessed in 104 positive sera and 1149 'normal' sera from healthy young adults, were 99.0% and 97.1% respectively. sensitivity of the wb was cl ...200516050523
enteric fever-like illness caused by infection with citrobacter amalonaticus.'enteric fever' is a potentially fatal, severe systemic disease, which is encountered worldwide. traditionally, enteric fever refers to a bacteremic illness caused by members of certain salmonella serotypes, notably: salmonella typhi, a gram-negative bacterium, and to a lesser extent, salmonella paratyphi a, b and c. in addition, other non-salmonella organisms may produce a syndrome clinically indistinguishable from "enteric fever". brucella sp., campylobacter sp., edwardsiella tarda, enterobact ...200516083226
massive attack. 200516094740
dna assays for detection, identification, and individualization of select agent microorganisms.the purpose of this article is to review the status of dna assays used for the detection, identification, and individualization of bacillus anthracis, yersinia pestis, francisella tularensis, burkholderia mallei, and brucella abortus. these select agent microorganisms are historically significant as they have either been used or experimented with as a bioweapon or as a terrorist agent and are the subject of intense research in the areas of biodefense and bioforensics. if the presence of a biolog ...200516100754
[diagnostic tests: tularemia]. 200516111241
francisella tularensis enters macrophages via a novel process involving pseudopod loops.intracellular bacterial pathogens employ a variety of strategies to invade their eukaryotic host cells. from an ultrastructural standpoint, the processes that bacteria employ to invade their host cells include conventional phagocytosis, coiling phagocytosis, and ruffling/triggered macropinocytosis. in this paper, we describe a novel process by which francisella tularensis, the agent of tularemia, enters host macrophages. f. tularensis is a remarkably infectious facultative intracellular bacteria ...200516113308
antimicrobial susceptibilities of austrian francisella tularensis holarctica biovar ii strains.the antibiotic susceptibilities of 50 francisella tularensis subsp. holarctica biovar ii strains isolated from hares and human patients from the eastern part of austria were examined. minimum inhibitory concentrations (mics) of 24 antimicrobial agents were determined using eteststrade mark on cysteine heart agar plates supplemented with 10% sheep blood. all isolates were sensitive to tetracyclines, aminoglycosides, quinolones, chloramphenicol and rifampicin. resistance was observed in all isolat ...200516143497
[phase variations of francisella tularensis lipopolysaccharide in human infection and immunization].the comparative study of the specificity of antibodies in human sera after tularemia infection and immunization with live tularemia infection was carried out with the use of passive hemagglutination and immunoblotting techniques. the sera of tularemia patients contained two different types of immunoglobulins: strictly specific to the antigenic epitopes of f. tularensis iipopolysaccharide (lps) and strictly specific to f. tularensis subsp. novicida lps. such phenomenon may be due to phase variati ...200516146218
detection of diverse new francisella-like bacteria in environmental samples.following detection of putative francisella species in aerosol samples from houston, texas, we surveyed soil and water samples from the area for the agent of tularemia, francisella tularensis, and related species. the initial survey used 16s rrna gene primers to detect francisella species and related organisms by pcr amplification of dna extracts from environmental samples. this analysis indicated that sequences related to francisella were present in one water and seven soil samples. this is the ...200516151142
outbreak of tularaemia in golcuk, turkey in 2005: report of 5 cases and an overview of the literature from turkey.tularaemia was diagnosed by taqman rt-pcr and microagglutination tests in 5 patients, all from a new settlement constructed after the earthquake of 1999. during the follow-up, 129 more cases were found in this settlement (data from the local health care authority). in this study, clinical features of 5 cases are presented briefly, and the turkish literature on past outbreaks of tularaemia is reviewed.200516191887
use of shell-vial cell culture assay for isolation of bacteria from clinical specimens: 13 years of experience.the shell-vial culture assay is performed routinely in our laboratory. recently we revisited our experience of using the shell-vial culture assay for the isolation of microorganisms from various clinical samples. over a 13-year period, we have isolated 580 bacterial strains (5%) from 11,083 clinical samples tested. over the same period, 285 isolates of rickettsiae, bartonellae, or coxiella burnetii were cultured from a total of 7,102 samples tested. these isolates include 55 rickettsia sp. isola ...200516207953
tularemia in denmark: identification of a francisella tularensis subsp. holarctica strain by real-time pcr and high-resolution typing by multiple-locus variable-number tandem repeat analysis.we report ulceroglandular tularemia affecting an 8-year-old boy and the first recovery of francisella tularensis in denmark. a novel real-time pcr assay was used to identify the strain as f. tularensis subsp. holarctica (type b). multiple-locus variable-number tandem repeat analysis demonstrated a close genetic relationship to strains from norway.200516208017
[tularemia]. 200516209241
francisella tularensis proteome: low levels of asb-14 facilitate the visualization of membrane proteins in total protein extracts.proteomic analysis of bacterial pathogens isolated from in vivo sources, such as infected tissues, provides many challenges not the least of which is the limited quantity of sample available for analysis. it is, therefore, highly desirable to develop a one-step cellular lysis and protein solubilization method that minimizes protein losses and allows the maximum possible coverage of the proteome. here, we have used standard sample buffer constituents including urea, thiourea and dtt, but varied t ...200516212441
diagnostic procedures in tularaemia with special focus on molecular and immunological techniques.tularaemia is a severe bacterial zoonosis caused by the highly infectious agent francisella tularensis. it is endemic in countries of the northern hemisphere ranging from north america to europe, asia and japan. very recently, francisella-like strains causing disease in humans were described from tropical northern australia. in the last decade, efforts have been made to develop sensitive and specific immunological and molecular techniques for the laboratory diagnosis of tularaemia and also for t ...200516219088
in vivo efficacy of fluoroquinolones against systemic tularaemia infection in mice.the in vivo efficacy of ciprofloxacin, gatifloxacin and moxifloxacin were assessed in an experimental francisella tularensis schu s4 infection in the balb/c mouse model.200516223941
innate immunity against francisella tularensis is dependent on the asc/caspase-1 axis.francisella tularensis is a highly infectious gram-negative coccobacillus that causes the zoonosis tularemia. this bacterial pathogen causes a plague-like disease in humans after exposure to as few as 10 cells. many of the mechanisms by which the innate immune system fights francisella are unknown. here we show that wild-type francisella, which reach the cytosol, but not francisella mutants that remain localized to the vacuole, induced a host defense response in macrophages, which is dependent o ...200516230474
a multiplex polymerase chain reaction microarray assay to detect bioterror pathogens in blood.heightened concern about the dangers of bioterrorism requires that measures be developed to ensure the safety of the blood supply. multiplex detection of such agents using a blood-screening dna microarray is a sensitive and specific method to screen simultaneously for a number of suspected agents. we have developed and optimized a multiplex polymerase chain reaction microarray assay to screen blood for three potential bioterror bacterial pathogens and a human ribosomal rna gene internal control. ...200516237218
discrimination of francisella tularensis subspecies using surface enhanced laser desorption ionization mass spectrometry and multivariate data analysis.francisella tularensis causes the zoonotic disease tularemia, and is considered a potential bioterrorist agent due to its extremely low infection dose and potential for airborne transmission. presently, f. tularensis is divided into four subspecies; tularensis, holarctica, mediasiatica and novicida. phenotypic discrimination of the closely related subspecies with traditional methods is difficult and tedious. furthermore, the results may be vague and they often need to be complemented with virule ...200515668033
infection scare inflames fight against biodefence network. 200515674255
biodefense labs. boston university under fire for pathogen mishap. 200515681355
oligo-chip based detection of tick-borne bacteria.we have developed an oligonucleotide-chip based assay for detection of 16s ribosomal pcr products from tick-borne bacteria. this chip contains 14 specific probes, which target variable regions of 16s rdna of tick-borne bacteria including borrellia spp., rickettsia spp., anaplasma spp., coxiella burnetii and francisella tularensis. the specificity of these probes was tested by hybridization of the chip with fluorescently labeled pcr products amplified from the genomic dna of selected tick-borne b ...200515686852
tularemia transmitted by insect bites--wyoming, 2001-2003.tularemia is a zoonotic disease caused by francisella tularensis, a fastidious, gram-negative coccobacillus that infects vertebrates, especially rabbits and rodents. in humans, tularemia is classified into six major syndromes: ulceroglandular (the most common form), glandular, typhoidal, oculoglandular, oropharyngeal, and pneumonic. the case-fatality rate among humans can reach 30%-60% in untreated typhoidal cases. although bites from ticks and handling infected animals are considered the most c ...200515729218
francisella tularensis lvs initially activates but subsequently down-regulates intracellular signaling and cytokine secretion in mouse monocytic and human peripheral blood mononuclear cells.monocytic cells constitute an important defense mechanism against invading pathogens by recognizing conserved pathogens components. the recognition leads to activation of intracellular pathways involving nuclear factor kappa b (nf-kappab) and mitogen-activated protein kinases (mapk), such as the c-jun nh2-terminal kinase (jnk), and p38. we show that in vitro infection with francisella tularensis results in activation of nf-kappab, phosphorylation of p38 and c-jun, and secretion of tnf-alpha in a ...200515925273
tularemia vaccine: past, present and future.francisella tularensis is a gram negative intracellular pathogen that causes the highly debilitating or fatal disease tularemia. f. tularensis can infect a wide range of animals and can be transmitted to humans in a variety of ways, the most common being by the bite of an infected insect or arthropod vector. the attenuated f. tularensis live vaccine strain (lvs) has been used previously under investigational new drug status to vaccinate at-risk individuals. however the history of the strain and ...200515928980
simultaneous measurement of specific serum igg responses to five select agents.select agents are defined by cdc and the usda animal and plant health inspection service (aphis) as biological agents or toxins deemed a threat to public, animal, or plant health, or to animal or plant products. they are classified on the basis of their ease of dissemination, mortality/morbidity rate, and potential for social disruption. a subset of these agents includes bacillus anthracis, yersinia pestis, francisella tularensis, ricin toxin (rt), and staphylococcal enterotoxin b (seb). infecti ...200515931499
crystallization of acpa, a respiratory burst-inhibiting acid phosphatase from francisella tularensis.francisella tularensis is a highly infectious bacterial pathogen that is classified as a category a pathogen by the centers for disease control and prevention. here, we report crystallization of a recombinant form of f. tularensis acpa, a unique and highly expressed acid phosphatase that is thought to play a role in intracellular survival by inhibiting the host respiratory burst. three crystal forms have been obtained, with form iii being the most suitable for high-resolution structure determina ...200515935744
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