Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| [possible mechanisms of implementation of toxic potential of lipopolysaccharides of pathogenic bacteria]. | the significance of variability of biological properties of lipopolysaccharides (lps) is discussed in the paper within the pathogenesis of infectious process. on the basis of an analysis of published data and of results of independent research of two microorganisms (yersinia pestis and francisella tularensis) a conclusion is made on that a biologically inert lps form (with a weak cytokine-inducing ability, apirogenicity and non-toxicity etc.) is typical of highly pathogenic bacteria. it is sugge ... | 2005 | 15954469 |
| the francisella tularensis pathogenicity island protein iglc and its regulator mgla are essential for modulating phagosome biogenesis and subsequent bacterial escape into the cytoplasm. | the francisella tularensis subsp. novicida-containing phagosome (fcp) matures into a late endosome-like stage that acquires the late endosomal marker lamp-2 but does not fuse to lysosomes, for the first few hours after bacterial entry. this modulation in phagosome biogenesis is followed by disruption of the phagosome and bacterial escape into the cytoplasm where they replicate. here we examined the role of the francisella pathogenicity island (fpi) protein iglc and its regulator mgla in the intr ... | 2005 | 15953029 |
| modulation of biogenesis of the francisella tularensis subsp. novicida-containing phagosome in quiescent human macrophages and its maturation into a phagolysosome upon activation by ifn-gamma. | francisella tularensis is a highly virulent facultative intracellular pathogen that has been categorized as a class a bioterrorism agent, and is classified into four subsp, tularensis, holarctica, mediasiatica and novicida. although the ability of f. tularensis subsp. novicida to cause tularemia in mice is similar to the virulent subsp. tularensis and holarctica, it is attenuated in humans. it is not known whether attenuation of f. tularensis subsp. novicida in humans is resulting from a differe ... | 2005 | 15953028 |
| multiplexed detection of pathogen dna with dna-based fluorescence nanobarcodes. | rapid, multiplexed, sensitive and specific molecular detection is of great demand in gene profiling, drug screening, clinical diagnostics and environmental analysis. one of the major challenges in multiplexed analysis is to identify each specific reaction with a distinct label or 'code'. two encoding strategies are currently used: positional encoding, in which every potential reaction is preassigned a particular position on a solid-phase support such as a dna microarray, and reaction encoding, w ... | 2005 | 15951805 |
| structural analysis of the o-antigen of francisella tularensis subspecies tularensis strain osu 10. | 2005 | 15947437 | |
| francisella tularensis live vaccine strain: proteomic analysis of membrane proteins enriched fraction. | proteome analysis of gram-negative facultative intracellular pathogen francisella tularensis (f. tularensis) live vaccine strain has been performed only on whole-cell extracts so far. this is the first study dealing with the analysis of the membrane subproteome of this microorganism. a fraction enriched in membrane proteins obtained by carbonate extraction was separated using two-dimensional electrophoresis and all visualized spots were identified by mass spectrometry. the reference map is the b ... | 2005 | 15937965 |
| 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 ... | 2005 | 15935744 |
| 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 ... | 2005 | 15931499 |
| 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 ... | 2005 | 15928980 |
| 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 ... | 2005 | 15925273 |
| early activation of nk cells after lung infection with the intracellular bacterium, francisella tularensis lvs. | francisella tularensis is a gram-negative intracellular bacterium that has been classified as a category a biothreat because of its ability to induce deadly pneumonic tularemia when inhaled. in the present study, an experimental model of f. tularensis lvs intranasal infection was used to study the immune cells involved in cytokine secretion in the lungs after infection. dramatic increases in the numbers of cells secreting ifn-gamma were observed 72 h after intranasal infection of balb/c and c57b ... | 2004 | 15922718 |
| vaccination strategies for francisella tularensis. | francisella tularensis is the etiologic agent of tularemia, a severe debilitating disease of humans and animals. the low infectious dose of f. tularensis in humans and the relative ease of culture are probably the properties which originally attracted interest in this bacterium as a bioweapon. even today, f. tularensis is ranked as one of the pathogens most likely to be used as a biological warfare or bioterrorism agent. a live attenuated vaccine (lvs) has been available for over 50 years, but t ... | 2005 | 15919131 |
| evolution of subspecies of francisella tularensis. | analysis of unidirectional genomic deletion events and single nucleotide variations suggested that the four subspecies of francisella tularensis have evolved by vertical descent. the analysis indicated an evolutionary scenario where the highly virulent f. tularensis subsp. tularensis (type a) appeared before the less virulent f. tularensis subsp. holarctica (type b). compared to their virulent progenitors, attenuated strains of f. tularensis exhibited specific unidirectional gene losses. | 2005 | 15901721 |
| [case report: a case of tularemia with delayed diagnosis]. | tularemia is a zoonotic disease caused by francisella tularensis. in this report, a tularemia case who was living in a non-endemic area, has been presented. a 24 years old female patient with multiple cervical lymphadenitis has been admitted to the outpatient clinic of ankara training and research hospital, turkey. her complaints started two months ago as signs and symptoms of an upper respiratory tract infection. as she had received non-specific treatment (amoxycillin clavulanate; 2x 1g/day) in ... | 2005 | 15900842 |
| host-pathogen interactions: a proteomic view. | host-pathogen interactions reflect the balance of host defenses and pathogen virulence mechanisms. advances in proteomic technologies now afford opportunities to compare protein content between complex biologic systems ranging from cells to animals and clinical samples. thus, it is now possible to characterize host-pathogen interactions from a global proteomic view. most reports to date focus on cataloging protein content of pathogens and identifying virulence-associated proteins or proteomic al ... | 2005 | 15892564 |
| proteomic analysis of anti-francisella tularensis lvs antibody response in murine model of tularemia. | francisella tularensis live vaccine strain infection of mice has been established as an experimental model of tularemia that is suitable for studies of immune mechanisms against the intracellular pathogen. in this study, the model was used to explore immunogenic repertoire of f. tularensis with the aim of identifying new molecules able to activate the host immune system, potential bacterial markers with vaccine, and diagnostic applications. immunoproteomic approach based on the combination of tw ... | 2005 | 15892173 |
| [investigation on mixed natural foci of zoonotic infections]. | 2005 | 15881957 | |
| [cross-reacting antigens of pathogenic burkholderia and some dangerous causative agents of infectious diseases]. | cross-reacting antigens in b. mallei, b. pseudomallei, b. thailandensis, francisella tularensis, yersinia pestis and mycobacterium tuberculosis were studied with the use of immuno- and electrophoretic techniques. the set of antigens was shown to be almost identical in the causative agents of glanders, melioidosis, as well as in b. thailandensis, though in the latter organism 200-kd glycoprotein was absent. the analysis of immuno- and proteinograms demonstrated the presence of cross-reactions in ... | 2005 | 15881932 |
| [tularemia. the disease and its epidemiology in france]. | this study had for aim to determine whether the epidemiologic features of animal and human tularemia observed in france could explain its re-emergence since 1993. | 2005 | 15878815 |
| insights into the oxidative stress response in francisella tularensis lvs and its mutant deltaiglc1+2 by proteomics analysis. | francisella tularensis is a facultative intracellular pathogen. its capacity to induce disease depends on the ability to invade and multiply within a wide range of eukaryotic cells, such as professional phagocytes. the comparative disinterest in tularemia in the past relative to other human bacterial pathogens is reflected in the paucity of information concerning the mechanisms of pathogenesis. only a few genes and gene products associated with francisella virulence are known to date. the aim of ... | 2005 | 15869961 |
| tularemia in a kidney transplant recipient: an unsuspected case and literature review. | tularemia is a zoonotic infection that has rarely been reported in transplant recipients. the authors present a case of unsuspected tularemia in a kidney transplant patient that was diagnosed by isolation of francisella tularensis in the blood. the patient was treated successfully with antibiotics. during diagnostic workup, a laboratory technician was exposed to tularemia by inhalation of the culture plate and received postexposure prophylaxis. this report emphasizes the importance of exposure h ... | 2005 | 15861359 |
| lipopolysaccharide microarrays for the detection of antibodies. | lipopolysaccharide (lps) is the major component of gram-negative bacterial outer membrane. lps are immunogenic and show species/strain specificity. the demonstration of anti-lps antibodies in clinical samples is of diagnostic value in certain gram-negative bacterial infections. in the present study we explored the possibility of immobilizing lps isolated from different bacteria in a microarray format for the detection of anti-lps antibodies. lps was successfully immobilized on nitrocellulose-coa ... | 2005 | 15847798 |
| intranasal vaccination induces protective immunity against intranasal infection with virulent francisella tularensis biovar a. | the inhalation of francisella tularensis biovar a causes pneumonic tularemia associated with high morbidity and mortality rates in humans. exposure to f. tularensis usually occurs by accident, but there is increasing awareness that f. tularensis may be deliberately released in an act of bioterrorism or war. the development of a vaccine against pneumonic tularemia has been limited by a lack of information regarding the mechanisms required to protect against this disease. vaccine models for f. tul ... | 2005 | 15845466 |
| tularemia: emergence/re-emergence. | francisella tularensis is a gram-negative coccobacillus and the etiologic agent of the zoonotic disease tularemia. first described in 1911 in tulare county, california, it has since been reported throughout the northern hemisphere, with natural infections reported among an unusually wide range of vertebrates and invertebrates. in recent years, tularemia has emerged in new geographic locations, populations, and settings. this review will serve to highlight mechanisms contributing to the recent em ... | 2005 | 15845234 |
| epizootiologic investigations of selected infectious disease agents in free-ranging eurasian lynx from sweden. | serum samples from 106 eurasian lynx (lynx lynx) from across sweden, found dead or shot by hunters in 1993-99, were investigated for presence of antibodies to feline parvovirus (fpv), feline coronavirus, feline calicivirus, feline herpesvirus, feline immunodeficiency virus, francisella tularensis, and anaplasma phagocytophila, and for feline leukemia virus antigen. in addition, tissue samples from 22 lynx submitted in 1999 were analyzed by real-time polymerase chain reaction (pcr) to detect nucl ... | 2005 | 15827211 |
| the role of mapk signal pathways during francisella tularensis lvs infection-induced apoptosis in murine macrophages. | francisella tularensis is a highly virulent intracellular pathogen responsible for tularemia. this bacterium is capable of infecting many mammalian species and various cell types, but little is known about the mechanisms of survival and interactions with host cells. we examined the number of infected host cells, cytotoxicity and the role of apoptosis or necrosis in infection-induced cell death. our results demonstrate that f. tularensis lvs induces apoptosis of infected macrophages within 10 h. ... | 2005 | 15820149 |
| the contribution of reactive nitrogen and oxygen species to the killing of francisella tularensis lvs by murine macrophages. | intracellular killing of francisella tularensis by macrophages depends on interferon-gamma (ifn-gamma)-induced activation of the cells. the importance of inducible nitric oxide synthase (inos) or nadph phagocyte oxidase (phox) for the cidal activity was studied. murine ifn-gamma-activated peritoneal exudate cells (pec) produced nitric oxide (no), measured as nitrite plus nitrate, and superoxide. when pec were infected with the live vaccine strain, lvs, of f. tularensis, the number of viable bact ... | 2005 | 15788155 |
| intranasal interleukin-12 treatment for protection against respiratory infection with the francisella tularensis live vaccine strain. | francisella tularensis is a gram-negative intracellular bacterium that can induce lethal respiratory infection in humans and rodents. however, little is known about the role of innate or adaptive immunity in protection from respiratory tularemia. in the present study, the role of interleukin-12 (il-12) in inducing protective immunity in the lungs against intranasal infection of mice with the live vaccine strain (lvs) of f. tularensis was investigated. it was found that gamma interferon (ifn-gamm ... | 2005 | 15784575 |
| efficacy of the live attenuated francisella tularensis vaccine (lvs) in a murine model of disease. | a live attenuated vaccine francisella tularensis live vaccine strain (lvs), that confers protection against tularemia infection in a number of animal models including man was developed during the 1960s in the us. in this study, we have established the median lethal dose (mld) after intraperitoneal (i.p.) or intravenous (i.v.) delivery of ndbr lot 4 f. tularensis lvs to be 4 cfu and 2.24 x 10(4) cfu, respectively, in balb/c mice and less than 1 cfu and 1.29 x 10(4) cfu, respectively, in c57bl/6 m ... | 2005 | 15780452 |
| [tularemia acquired in denmark by an eight-year-old child]. | 2005 | 15779266 | |
| [pathogenicity of francisella]. | the data of literature and the results of the author's research on the pathogenicity of the causative agent of tularemia and other francisella organisms are reviewed. the solution of the problem of their pathogenicity is based, as stated by the author, on the level of our knowledge of the genetics of francisella. the conclusion has been made that scientific achievements in the field of the genetics of francisella, obtained during the last 15 years, make it possible to find out the pathogenicity ... | 2005 | 15773415 |
| tularaemia outbreak in bulgaria. | during the last 40 y, 2 large tularaemia outbreaks occurred in bulgaria. we report the second outbreak, in 1998--2003, including a total of 262 laboratory confirmed cases. the majority of the patients presented with oropharyngeal tularaemia (89.7%). less common were the glandular, pulmonary and oculoglandular forms. the diagnosis of tularaemia was confirmed serologically. in 5 cases, f. tularensis was detected by immunofluorescent assay in lymph node biopsies. by pcr, all 5 samples yielded succe ... | 2004 | 15764161 |
| 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 ... | 2005 | 15758077 |
| 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 ... | 2005 | 15752834 |
| [francisella tularensis infection, or how to outsmart the certain death]. | francisella tularensis is an intracellular bacterial pathogen and is the causative agent of tularemia. human become infected when manipulating with infected animals (usually rodents) or via arthropod vectors. in spite of the high virulence of the microbe still very little is known about its overall interaction with host cells and virulence factors identified to date show properties different from other bacterial species. | 2004 | 15745053 |
| 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 ... | 2005 | 15729218 |
| 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 ... | 2005 | 15686852 |
| biodefense labs. boston university under fire for pathogen mishap. | 2005 | 15681355 | |
| a multiplexed pcr-coupled liquid bead array for the simultaneous detection of four biothreat agents. | we have developed a 10-plexed pcr assay coupled to a 12-plexed liquid bead array to rapidly screen environmental samples for b. anthracis, y. pestis, f. tularensis, and b. melitensis. highly validated species-specific primer sets were used to simultaneously amplify multiple diagnostic regions unique to each individual pathogen. resolution of the mix of amplified products was achieved by pcr product hybridization to corresponding probe sequences, attached to unique sets of fluorescent beads. the ... | 2004 | 15680215 |
| bichat guidelines for the clinical management of tularaemia and bioterrorism-related tularaemia. | francisella tularensis is one of the most infectious pathogenic bacteria known, requiring inoculation or inhalation of as few as 10 organisms to initiate human infection. inhalational tularaemia following intentional release of a virulent strain of f. tularensis would have great impact and cause high morbidity and mortality. another route of contamination in a deliberate release could be contamination of water. seven clinical forms, according to route of inoculation (skin, mucous membranes, gast ... | 2004 | 15677845 |
| infection scare inflames fight against biodefence network. | 2005 | 15674255 | |
| 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 ... | 2005 | 15668033 |
| francisella tularensis peritonitis in stomach cancer patient. | tularemia with peritonitis developed in a 50-year-old man soon after diagnosis of stomach cancer with metastasis. the ascites grew francisella tularensis subsp. holarctica, which was identified by sequencing analysis of the 16s rdna. the infection resolved with antimicrobial treatment. antibodies detected 4 weeks after onset disappeared after chemotherapy-associated lymphopenia. | 2004 | 15663872 |
| serologic survey for canine infectious diseases among sympatric swift foxes (vulpes velox) and coyotes (canis latrans) in southeastern colorado. | swift foxes (vulpes velox) and coyotes (canis latrans) are sympatric canids distributed throughout many regions of the great plains of north america. the prevalence of canid diseases among these two species where they occur sympatrically is presently unknown. from january 1997 to january 2001, we collected blood samples from 89 swift foxes and 122 coyotes on the us army piñon canyon maneuver site, las animas county, se colorado (usa). seroprevalence of antibodies against canine parvovirus (cpv) ... | 2004 | 15650093 |
| serologic survey for selected disease agents in wolves (canis lupus) from alaska and the yukon territory, 1984-2000. | wolves (canis lupus) were captured in several geographic areas of alaska (usa) and the yukon territory (canada) during 1984-2000. blood was collected from 1,122 animals. sera were tested for antibodies against infectious canine hepatitis virus (ich), canine distemper virus (cdv), canine parvovirus (cpv), francisella tularensis, and serovars of leptospira interrogans. antibody prevalence for ich was >84% for all areas. area-specific prevalences of antibodies ranged from 12% to 70% for cpv, from 0 ... | 2004 | 15650081 |
| the complete genome sequence of francisella tularensis, the causative agent of tularemia. | francisella tularensis is one of the most infectious human pathogens known. in the past, both the former soviet union and the us had programs to develop weapons containing the bacterium. we report the complete genome sequence of a highly virulent isolate of f. tularensis (1,892,819 bp). the sequence uncovers previously uncharacterized genes encoding type iv pili, a surface polysaccharide and iron-acquisition systems. several virulence-associated genes were located in a putative pathogenicity isl ... | 2005 | 15640799 |
| the development of tools for diagnosis of tularemia and typing of francisella tularensis. | rapid development of molecular techniques for the diagnosis of infections and typing of microbes has been seen during the last 10 years. the present review exemplifies this development by presenting the work of the authors and others regarding techniques for the diagnosis of tularemia and typing of francisella tularensis. the lack of rapid and safe methods for the laboratory diagnosis of tularemia was the rationale behind the development of methods for the direct detection of f. tularensis in cl ... | 2004 | 15638842 |
| tularemia associated with a hamster bite--colorado, 2004. | in april 2004, the colorado department of public health and environment (cdphe) was notified about a boy aged 3 years with diagnosed tularemia associated with a hamster bite. tularemia has not been associated previously with pet hamsters. cdphe conducted an investigation to determine whether other owners of hamsters were at risk. clinicians and public health officials should be aware that pet hamsters are a potential source of tularemia. | 2005 | 15635290 |
| toll-like receptor 4 (tlr4) plays a relatively minor role in murine defense against primary intradermal infection with francisella tularensis lvs. | 2005 | 15626487 | |
| concomitant or consecutive infection with coxiella burnetii and tickborne diseases. | q fever is a worldwide zoonosis caused by coxiella burnetii, which can be isolated from ticks. reports of people with both q fever and other tickborne diseases are rare. in this study, we describe 6 patients with q fever who were infected with 1 of the following tickborne pathogens: rickettsia conorii (2 patients), rickettsia slovaca (2), rickettsia africae (1), and francisella tularensis (1). | 2004 | 15614696 |
| [tularemia from a cat bite]. | we report the first case in norway of a man who developed ulceroglandular tularaemia following a cat bite. if after feline contact, patients develop skin and soft-tissue infections that fail to respond to therapy with penicillin, physicians should consider the possibility of tularaemia. our patient was successfully treated with ciprofloxacin, which is effective against francisella tularensis and most pathogens associated with feline infections. a greater awareness of infections following a cat b ... | 2004 | 15608764 |
| [bite wound infections]. | the lifetime risk of experiencing a bite wound, human or animal, is approximately 50%, and bite wounds account for approximately 1% of all visits to emergency departments. the majority of bite wounds are inflicted by dogs and cats. | 2004 | 15608763 |
| variable presentation of the cause of lymphadenopathy in two children. | 2004 | 15602207 | |
| the bartonella henselae sucb gene encodes a dihydrolipoamide succinyltransferase protein reactive with sera from patients with cat-scratch disease. | bartonella henselae is a recently recognized pathogenic bacterium associated with cat-scratch disease, bacillary angiomatosis and bacillary peliosis. a recombinant clone expressing an immunoreactive antigen of b. henselae was isolated by screening a genomic dna cosmid library by western blotting with sera pooled from patients positive for b. henselae igg antibodies by indirect immunofluorescence (ifa). the deduced amino acid sequence of the 43.7 kda encoded protein was found to be 76.3 % identic ... | 2004 | 15585501 |
| broth microdilution susceptibility testing of francisella tularensis: quality control limits for nine antimicrobial agents and three standard quality control strains. | for broth microdilution susceptibility tests of francisella tularensis, mueller-hinton broth with 2% isovitalex is recommended. using that medium, we studied three standard control strains tested with nine antimicrobial agents potentially efficacious for treating tularemia. an eight-laboratory collaborative study generated the data needed to propose appropriate mic control limits. | 2004 | 15583330 |
| construction and characterization of a highly efficient francisella shuttle plasmid. | francisella tularensis is a facultative intracellular pathogen that infects a wide variety of mammals and causes tularemia in humans. it is recognized as a potential agent of bioterrorism due to its low infectious dose and multiple routes of transmission. to date, genetic manipulation in francisella spp. has been limited due to the inefficiency of dna transformation, the relative lack of useful selective markers, and the lack of stably replicating plasmids. therefore, the goal of this study was ... | 2004 | 15574954 |
| intranasal interleukin-12 treatment promotes antimicrobial clearance and survival in pulmonary francisella tularensis subsp. novicida infection. | francisella tularensis is a highly virulent facultative intracellular bacterium and is considered a potential biological warfare agent. inhalation tularemia can lead to the development of bronchopneumonia, which is frequently fatal without medical intervention. treatment strategies that directly target the respiratory mucosa may extend the efficacy of therapy, particularly for the medical management of acute aerosol exposure. to this end, we describe an intranasal (i.n.) strategy for the treatme ... | 2004 | 15561819 |
| distinct roles of reactive nitrogen and oxygen species to control infection with the facultative intracellular bacterium francisella tularensis. | reactive nitrogen species (rns) and reactive oxygen species (ros) are important mediators of the bactericidal host response. we investigated the contribution of these two mediators to the control of infection with the facultative intracellular bacterium francisella tularensis. when intradermally infected with the live vaccine strain f. tularensis lvs, mice deficient in production of rns (inos(-/-) mice) or in production of ros by the phagocyte oxidase (p47(phox-/-) mice) showed compromised resis ... | 2004 | 15557642 |
| tularaemia: bioterrorism defence renews interest in francisella tularensis. | francisella tularensis is a highly infectious aerosolizable intracellular pathogen that is capable of causing a debilitating or fatal disease with doses as low as 25 colony-forming units. there is no licensed vaccine available. since the 1950s there has been concern that f. tularensis could be used as a biological threat agent, and it has received renewed attention recently owing to concerns about bioterrorism. the international conference on tularaemia in 2003 attracted more than 200 delegates, ... | 2004 | 15550942 |
| comparison of enzyme-linked immunosorbent assay, western blotting, microagglutination, indirect immunofluorescence assay, and flow cytometry for serological diagnosis of tularemia. | the serodiagnostic efficiencies of five different approaches to detecting antibodies (immunoglobulins g, a, and m) developed in clinically proven infections with francisella tularensis have been assessed. fifty serum samples from patients suffering from tularemia during an outbreak in sweden were compared with samples from 50 healthy blood donors (controls) by using an enzyme-linked immunosorbent assay (elisa), microagglutination (ma), western blotting (wb), an indirect immunofluorescence assay ... | 2004 | 15539498 |
| genotypic diversity of francisella tularensis infecting dermacentor variabilis ticks on martha's vineyard, massachusetts. | martha's vineyard, mass., has been the site of two outbreaks of tularemia (1978 and 2000). although most patients from both outbreaks presented with pneumonic disease and although aerosol transmission has been suggested, the bite of a dog tick and exposure to rabbits remain the only proven modes of transmission. the factors that precipitated the tularemia outbreaks or the proximal determinants of human risk remain undescribed. we sought to test the hypothesis that the ongoing outbreak is due to ... | 2004 | 15528681 |
| use of transposon-transposase complexes to create stable insertion mutant strains of francisella tularensis lvs. | francisella tularensis is a highly virulent zoonotic bacterial pathogen capable of infecting numerous different mammalian species, including humans. elucidation of the pathogenic mechanisms of f. tularensis has been hampered by a lack of tools to genetically manipulate this organism. herein we describe the use of transposome complexes to create insertion mutations in the chromosome of the f. tularensis live vaccine strain (lvs). a tn5-derived transposon encoding kanamycin resistance and lacking ... | 2004 | 15528561 |
| molecular recognition of biowarfare agents using micromechanical sensors. | recent terrorist events have demonstrated that an urgent and widespread need exists for the development of novel sensors for threat detection, especially biowarfare agents. the advent of inexpensive, mass-produced microcantilever sensors promises to bring about a revolution in detection of terrorist threats. extremely sensitive and highly selective sensors can be developed for using a microcantilever platform. microcantilevers undergo bending when molecules are adsorbed on a single side. for bio ... | 2004 | 15525227 |
| [should ticks be regarded as a tularemia vector in habitants of north-eastern poland?]. | a growing incidence of tick borne encephalitis and lyme borreliosis in north-eastern poland as well as an increasing number of ixodes ricinus ticks in wooded areas and meadows have prompted the authors to evaluate the presence of antibodies against francisella tularensis in serum of forest workers. | 2004 | 15524088 |
| expression of iglc is necessary for intracellular growth and induction of apoptosis in murine macrophages by francisella tularensis. | francisella tularensis is a facultative intracellular bacterium capable of inducing apoptosis in murine macrophages. in a previous study, an iglc null mutant of f. tularensis live vaccine strain lvs was generated by allelic replacement and in the current study this iglc mutant was successfully complemented in trans. we characterized the capacity of this iglc mutant and the complemented strain to induce macrophage apoptosis. the iglc mutant did not induce apoptosis in the infected cells. in contr ... | 2004 | 15519043 |
| [sero-epidemiological studies of zoonotic infections in hunters--comparative analysis with veterinarians, farmers, and abattoir workers]. | the aim of this study was to investigate seroprevalences to zoonotic pathogens in hunters, to compare the results with other predisposed occupational groups already investigated and to propose preventive measures. blood samples were taken from 146 male and 3 female hunters from the provinces of styria and burgenland in the south-east of austria and anamnestic data were obtained using a questionnaire. the serological investigations included the following bacterial, viral and parasitic zoonotic ag ... | 2003 | 15508783 |
| [screening for antibodies against zoonotic agents among employees of the zoological garden of vienna, schönbrunn, austria]. | the aim of this study was to investigate the prevalence of antibodies against zoonotic agents in employees of the zoological garden of vienna, schönbrunn, austria. sixty out of 120 employees participated in the study. in 97% of them antibodies to at least one zoonotic agent were identified. only two participants were free of antibodies to the zoonotic agents tested. the following seroprevalences (in brackets) were obtained: viral zoonotic (and potentially zoonotic) agents: influenzavirus a/h1n1 ... | 2004 | 15495931 |
| did an epidemic of tularemia in ancient egypt affect the course of world history? | the dynamics of the spreading, and the identity of a virulent epidemic, similar to bubonic plague or typhus, which hit ancient egypt in the middle of the bronze age, are hereby presented. documented in medical papyri as well as archaeological findings, and re-echoed in biblical texts, a plague entered egypt's main harbor, avaris, around 1715 bc. as a result, the country was severely weakened at a time when it was already facing serious sociopolitical issues: crumbling central government, immigra ... | 2004 | 15488667 |
| detection of staphylococcus aureus enterotoxin a and b genes with pcr-eia and a hand-held electrochemical sensor. | two electrochemical assays for detecting staphylococcus aureus enterotoxin a and b genes were developed. the assays are based on pcr amplification with biotinylated primers, hybridization to a fluorescein-labeled probe, and detection with horseradish peroxidase-conjugated anti-fluorescein antibody using a hand-held electrochemical detector. the limit of detection (lod) for both assays was approximately 16 copies of the sea and seb genes. the assays were evaluated in blinded studies, each with 81 ... | 2004 | 15488376 |
| characterization of a wild-type strain of francisella tularensis isolated from a cat. | francisella tularensis type a is the primary cause of tularemia in animals and humans in north america. the majority of research on f. tularensis has been done with the attenuated live vaccine strain (lvs), which is a type b, but very few wild-type f. tularensis strains have been characterized. a gram-negative coccobacillus that was isolated in pure culture from the lungs of a cat that died after being lost for 5 days was received for identification at the virginia-maryland regional college of v ... | 2004 | 15460318 |
| identification of francisella tularensis genes encoding exported membrane-associated proteins using tnphoa mutagenesis of a genomic library. | francisella tularensis, the causative agent of tularemia, is a highly infectious pathogen of humans and animals, yet little is known about the surface proteins of this organism that mediate mechanisms of pathogenicity. lambdatnphoa was used to generate random alkaline phosphatase gene fusions in a f. tularensis subsp. tularensis (strain schu s4) genomic library to identify genes encoding exported extracytoplasmic proteins. eleven genes encoding membrane-associated proteins were identified by thi ... | 2004 | 15458781 |
| toll-like receptor 4 (tlr4) does not confer a resistance advantage on mice against low-dose aerosol infection with virulent type a francisella tularensis. | francisella tularensis, the causative agent of tularemia, is a gram-negative facultative intracellular bacterium. toll-like receptor (tlr) 4 is considered to be critical for inducing host innate immunity against many gram-negative bacteria including many respiratory pathogens. to determine the role of tlr4 in host defense against airborne f. tularensis infection, tlr4-defective c3h/hej (tlr4(d)) or wild-type c3h/heouj (wt) mice were challenged by low-dose aerosol with type a f. tularensis, and t ... | 2004 | 15458779 |
| comparative proteome analysis of cellular proteins extracted from highly virulent francisella tularensis ssp. tularensis and less virulent f. tularensis ssp. holarctica and f. tularensis ssp. mediaasiatica. | francisella tularensis is the causative agent of the zoonotic disease tularemia. four subspecies of this pathogen, namely ssp. tularensis, mediaasiatica, holarctica, and novicida are spread throughout the northern hemisphere. although there are marked variations in their virulence to mammals, the subspecies are difficult to identify as they are closely genetically related. we carried out the comparative proteome analysis of cellular extracts from isolates representing the highly virulent subspec ... | 2004 | 15378745 |
| a francisella tularensis pathogenicity island required for intramacrophage growth. | francisella tularensis is a gram-negative, facultative intracellular pathogen that causes the highly infectious zoonotic disease tularemia. we have discovered a ca. 30-kb pathogenicity island of f. tularensis (fpi) that includes four large open reading frames (orfs) of 2.5 to 3.9 kb and 13 orfs of 1.5 kb or smaller. previously, two small genes located near the center of the fpi were shown to be needed for intramacrophage growth. in this work we show that two of the large orfs, located toward the ... | 2004 | 15375123 |
| factors affecting the escape of francisella tularensis from the phagolysosome. | the highly virulent bacterium francisella tularensis is well adapted to the intracellular habitat but the mechanisms behind its intracellular survival have been elusive. recently, it was shown that the bacterium is capable of escaping from the phagosome of human and mouse monocytic cells. here it is shown that this escape is affected by gamma interferon (ifn-gamma) treatment of mouse peritoneal exudate cells since in treated cells the proportion that escaped was significantly lower (80%) than in ... | 2004 | 15358816 |
| naturally occurring tularemia in a dog. | a 4-year-old spayed female irish setter was examined because of acute onset of lethargy, anorexia, and weakness. the dog had eaten an adult rabbit 36 hours earlier. tularemia was suspected because of the rabbit exposure; however, other common diseases characterized by fever, malaise, and lymphadenopathy of acute onset were also considered (ie, ehrlichiosis and rocky mountain spotted fever). the dog was treated with doxycycline (5 mg/kg [2.3 mg/lb], po, q 24 h) for 14 days as well as supportive t ... | 2004 | 15344361 |
| msba transporter-dependent lipid a 1-dephosphorylation on the periplasmic surface of the inner membrane: topography of francisella novicida lpxe expressed in escherichia coli. | the lipid a anchor of francisella tularensis lipopolysaccharide (lps) lacks both phosphate groups present in escherichia coli lipid a. membranes of francisella novicida (an environmental strain related to f. tularensis) contain enzymes that dephosphorylate lipid a and its precursors at the 1- and 4'-positions. we now report the cloning and characterization of a membrane-bound phosphatase of f. novicida that selectively dephosphorylates the 1-position. by transferring an f. novicida genomic dna l ... | 2004 | 15339914 |
| novel modification of lipid a of francisella tularensis. | we have investigated the lipid a of francisella tularensis subsp. holarctica strain 1547-57, a type b strain, by using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry, nanoelectrospray quadrupole ion-trap mass spectrometry, and chemical methods. in accordance with the previously published structures of the lipid a from f. tularensis live vaccine strain (lvs) (atcc 29684) (e. vinogradov et al., eur. j. biochem. 269:6112-6118, 2002), all of the major lipid a forms from ... | 2004 | 15322031 |
| worldwide genetic relationships among francisella tularensis isolates determined by multiple-locus variable-number tandem repeat analysis. | the intracellular bacterium francisella tularensis is the causative agent of tularemia and poses a serious threat as an agent of bioterrorism. we have developed a highly effective molecular subtyping system from 25 variable-number tandem repeat (vntr) loci. in our study, multiple-locus vntr analysis (mlva) was used to analyze genetic relationships and potential population structure within a global collection of 192 f. tularensis isolates, including representatives from each of the four subspecie ... | 2004 | 15317786 |
| mice sublethally infected with francisella novicida u112 develop only marginal protective immunity against systemic or aerosol challenge with virulent type a or b strains of f. tularensis. | the current study determined the ability of francisella novicida to act as a live vaccine against the much more virulent, but closely related pathogen, francisella tularensis. live attenuated strains of the latter are effective vaccines against human tularemia. however, the molecular cause of their attenuation remains unknown, and this is a regulatory barrier for licensing such vaccines. moreover, f. tularensis is exceptionally difficult to manipulate genetically. this is hampering the developme ... | 2004 | 15312850 |
| [tick borne zoonosis: selected clinical and diagnostic aspects]. | tick-borne zoonotic infections are among the most diffuse vector borne diseases: these large group of infections is caused by different microorganisms: babesia spp., borrelia spp., rickettsia spp., ehrlichia spp., francisella tularensis, coxiella burnetii) and tick-borne encephalitis virus. babesiosis is caused by the protozoa (sporozoa) babesia microti and it is quite rare in humans in europe. the ixodids ticks are the competent vectors. a few symptomatic cases have been reported, mainly in spl ... | 2004 | 15305697 |
| tularaemia in europe: an epidemiological overview. | tularaemia exists endemically in most european countries. in some areas, such as finland and sweden, outbreaks comprising hundreds of cases are recorded at least once a decade. in other areas, outbreaks of such a magnitude occur only occasionally, except in times of war. between outbreaks, the natural reservoir of the causative agent, francisella tularensis, is unknown. the organism replicates intracellularly in protozoans. an association of tularaemia to natural water may be of significance in ... | 2004 | 15287379 |
| tularaemia in a captive golden-headed lion tamarin (leontopithecus chrysomelas) in switzerland. | 2004 | 15285287 | |
| [evolution of serological characteristics in 26 patients with tularemia three years after the outbreak]. | tularemia was an unknown zoonosis in our region until the first quarter of 1998. the outbreak that took place on those dates has made possible to study some scantly known characteristics of the disease, as are the determinants for the persistence of a high antibody titer. | 2004 | 15274779 |
| genome diversity among regional populations of francisella tularensis subspecies tularensis and francisella tularensis subspecies holarctica isolated from the us. | francisella tularensis is a highly infectious facultative intracellular pathogen that is considered a potential agent of bioterrorism. four different f. tularensis subspecies have been identified and they appear to display different ecological and virulence characteristics as well as differences in geographical distribution. one simple explanation for the variation in ecological and virulence characteristics is that they are conferred by differences in genome content. to characterize genome cont ... | 2004 | 15268932 |
| protection afforded by heat shock protein 60 from francisella tularensis is due to copurified lipopolysaccharide. | heat shock proteins (hsps) have attracted significant attention as protective antigens against a range of diseases caused by bacterial pathogens. however, more recently there have been suggestions that the protective response is due to the presence of peptide components other than hsps. we have shown that mice that had been immunized with purified heat shock protein 60 (hsp60) isolated from francisella tularensis were protected against a subsequent challenge with some strains of the bacterium. h ... | 2004 | 15213156 |
| tularemia: the disease and the weapon. | tularemia is a bacterial infection usually transmitted via arthropod vectors or direct contact with infected animals. naturally occurring cases are relatively rare, and can result in six different clinical syndromes. tularemia is also a potential agent of bioterrorism or biowarfare, and is categorized as a high-level threat. effective antibiotic treatment is available, including potential use of oral antibiotics in a mass casualty situation. an awareness of potential clinical presentations of tu ... | 2004 | 15207312 |
| [francisella tularensis infection transmitted by prairie dog]. | tularemia is a zoonosis caused by francisella tularensis; it mainly affects wild animals and only occasionally affects human beings. uncontrolled trade involving "exotic" animals could become a new route of acquisition. we report the case of a 3-year-old boy who contracted the disease through a bite from a prairie dog. outbreaks of tularemia have recently been described in some of these animals captured in texas (usa) and subsequently sold to other countries. infection due to yersinia pestis has ... | 2004 | 15207172 |
| immunobiology of the tomatine adjuvant. | soluble or sub-unit protein vaccines alone are incapable of generating antigen-specific cellular immune responses. this failure can be attributed to the manner in which the immune system processes antigen; endogenous antigens are cycled through the mhc class i pathway to stimulate cd8+ restricted responses and exogenous antigens are processed through the mhc class ii pathway to generate humoral immunity. traditionally sub-unit vaccines have been formulated with adjuvants to enhance immunogenicit ... | 2004 | 15193398 |
| [experimental study on the possibility of using live tularemia vaccine to increase resistance to heterologous infection disease]. | in experiments on guinea pigs immunized with francisella tularensis 15, or live tularemia vaccine (ltv), the level of heterologous protective effect to dangerous infectious diseases caused by yersinia pestis, burkholderia pseudomallei, b. mallei, mycobacterium tuberculosis was studied. the study revealed that during the first 4 weeks after the subcutaneous immunization with ltv the level of resistance of the immunized animals to heterologous infective agent reliably increased as indicated by the ... | 2004 | 15188557 |
| [multilocus vntr-typing of francisella tularensis strains]. | in the analysis of f. tularensis genome with the use of the specially developed program "dna" a great number of loci containing tandem repeats were found. for analysis, 3 of them were selected and designated as fta, ftb, ftc. the study of dna of 40 f. tularensis strains in the polymerase chain reaction with specific primers to these loci a great variability in the number of repeats was established, the presence of 17 alleles being found in locus fta, 5 alleles in locus ftb and 5 alleles in locus ... | 2004 | 15188553 |
| phylogenetic analysis of the francisella-like endosymbionts of dermacentor ticks. | bacterial endosymbionts with significant homology to francisella tularensis (gamma-proteobacteria) have been described from at least five species of ticks in three different genera, including two north american dermacentor species [d. andersoni stiles and d. variabilis (say)]. the evolutionary relationships among the francisella-like endosymbionts (fle) from different hosts and between fle and the arthropod-borne pathogen f. tularensis are not known. a 1,169-base fragment of the 16s rdna and a 7 ... | 2004 | 15185926 |
| methods for enhanced culture recovery of francisella tularensis. | francisella tularensis is found in a wide variety of hosts and extrahost environments, making culture recovery a diagnostic challenge. here we demonstrate improved recovery times and good sensitivity (90%) when cultures were inoculated on the site of an investigation using fresh tissues. for contaminated specimens, antibiotic supplementation of enriched cysteine heart agar blood culture medium improved recovery of f. tularensis by 81.1%. for transport of tissues, immediate freezing yielded cultu ... | 2004 | 15184180 |
| characterisation of the core part of the lipopolysaccharide o-antigen of francisella novicida (u112). | francisella novicida (u112), a close relative of the highly virulent bacterium f. tularensis, is known to produce a lipopolysaccharide that is significantly different in biological properties from the lps of f. tularensis. here we present the results of the structural analysis of the f. novicida lps core part, which is found to be similar to that of f. tularensis, differing only by one additional alpha-glc residue:where r is an o-chain, linked via a beta-bacillosamine (2,4-diamino-2,4,6-trideoxy ... | 2004 | 15183739 |
| vaccines against francisella tularensis--past, present and future. | francisella tularensis is a facultative intracellular bacterial pathogen capable of causing a spectrum of human diseases collectively called tularemia. the pathogen is highly infectious and some strains can cause rapidly lethal infection especially when inhaled. the latter were developed as biological weapons in the past and nowadays cause concern as potential bioterrorism agents. a live attenuated strain of the pathogen was developed more that 40 years ago and remains the sole prophylactic meas ... | 2004 | 15176947 |
| [genotyping of the francisella tularensis strains isolated from natural foci of tularemia in the rostov region by multilocus vntr analysis]. | on the basis of an analysis of the vntr alleles' distribution in 109 strains of f. tularensis it was established that 19 genotypes of the disease causative agent circulated in the rostov region from 1945 to 2002. the microbe-provoked infection episodes can be divided into polyclonal, monoclonal and cluster ones. a retrospective analysis of the genotypes' distribution is indicative of that strains of similar or of closely-related genotypes circulate simultaneously in the studied territory. all in ... | 2004 | 15164717 |
| molecular beacons for multiplex detection of four bacterial bioterrorism agents. | 2004 | 15161722 | |
| virulent and avirulent strains of francisella tularensis prevent acidification and maturation of their phagosomes and escape into the cytoplasm in human macrophages. | francisella tularensis, the agent of tularemia, is an intracellular pathogen, but little is known about the compartment in which it resides in human macrophages. we have examined the interaction of a recent virulent clinical isolate of f. tularensis subsp. tularensis and the live vaccine strain with human macrophages by immunoelectron and confocal immunofluorescence microscopy. we assessed the maturation of the f. tularensis phagosome by examining its acquisition of the lysosome-associated membr ... | 2004 | 15155622 |
| transfer of specific antibodies results in increased expression of tnf-alpha and il12 and recruitment of neutrophils to the site of a cutaneous francisella tularensis infection. | this study demonstrates that passive transfer of francisella tularensis-specific antibodies before experimental cutaneous infection with the live vaccine strain of f. tularensis has profound effects. recipient mice showed stronger staining for tnf-alpha and il12, and larger numbers of neutrophils in skin samples after infection than control mice. | 2004 | 15150328 |
| susceptibility of various mouse strains to systemically- or aerosol-initiated tularemia by virulent type a francisella tularensis before and after immunization with the attenuated live vaccine strain of the pathogen. | the following study determined whether commonly available mouse strains could be used to reveal vaccines capable of protecting against aerosol exposure to virulent type a strains of francisella tularensis. the attenuated live vaccine strain (lvs) of the pathogen, f. tularensis lvs, was used as the model vaccine for these studies. the results showed that most mouse strains survived intradermal immunization with 10(5)cfu of lvs, except for a/j mice the majority of which died following exposure to ... | 2004 | 15149767 |