| pathological changes in rabbits injected with pasteurella tularensis killed by ionizing radiation. | | 1969 | 5795104 |
| [leukocytolysis reaction and the neutrophil damage test as methods of demonstrating allergy to francisella tularensis]. | | 1981 | 7269912 |
| in vitro interactions between rabbit alveolar macrophages and pasteurella tularensis. | nutter, j. e. (fort detrick, frederick, md.), and q. n. myrvik. in vitro interactions between rabbit alveolar macrophages and pasteurella tularensis. j. bacteriol. 92:645-651. 1966.-rabbit alveolar macrophages were successfully employed in a study of host cell-pasteurella tularensis interactions in vitro. under cell culture conditions in which inhibitory antibiotics were not employed and small infection ratios were used, the relative in vivo virulence of two strains of p. tularensis was duplicat ... | 1966 | 5922539 |
| [further study of intraspecific taxonomy of francisella tularensis]. | | 1981 | 7331604 |
| [natural focus of tularemia on the kerchen peninsula (crimea)]. | the study confirming the existence of the steppe-type natural focus of tularemia on the kerch peninsula has been carried out. for the first time the cultures of francisella tularensis have been isolated. voles and house mice play the main role in the circulation of the infection. the parasitic system comprises ticks (ixodidae and nyalomma), as well as some species of fleas. in carrying out erizootological studies for detecting tularemia in the crimea the use of low temperature (0 degrees c) for ... | 1981 | 7331615 |
| modulation of the immune response by aerodin. ii. influence on the antiinfectious resistance in rabbits and guinea pigs experimentally infected by francisella tularensis and pseudomonas aeruginosa. | | 1981 | 7332454 |
| respiratory tularemia: comparison of selected routes of vaccination in fischer 344 rats. | fischer 344 rats were given the attenuated live vaccine strain of francisella tularensis by small-particle aerosol, intranasal instillation, or intraperitoneal, intramuscular, or subcutaneous injection. all of the vaccinated rats developed subclinical infection by 3 days after exposure, which cleared by day 28. temporal patterns and concentrations of the live vaccine strain organism within the hosts were dependent on the route of vaccination. pathological alterations were limited to minimal lung ... | 1981 | 7333669 |
| treatment of tularemia, including pulmonary tularemia, with gentamicin. | an alternative to streptomycin for treatment of possible tularemia would be useful on occasions when a patient develops a perplexing pneumonia that does not respond to initial treatment. in geographic areas where tularemia is endemic, an antimicrobial drug that is bactericidal for francisella tularensis and is also effective against a spectrum of common pulmonary pathogens, including the enterobacteriaceae and most strains of pseudomonas aeruginosa, would be desirable. the purposes of this repor ... | 1980 | 7352712 |
| cross-reaction to legionella pneumophila antigen in sera with elevated titers to pseudomonas pseudomallei. | a significantly greater incidence (p less than 0.005) of legionella pneumophila microagglutination titers greater than or equal to 32 was found in sera with elevated titers to pseudomonas pseudomallei as compared with sera with negative titers for p. pseudomallei antibodies. the greater incidence of l. pneumophila titers in these sera suggests that l. pneumophila and p. pseudomallei share an antigen. the incidence of l. pneumophila microagglutination titers of greater than or equal to 32 in sera ... | 1980 | 7354127 |
| antigenic composition of a vaccine strain of francisella tularensis. | the antigenic composition of the live vaccine strain of francisella tularensis was investigated. ether-water extracts, water-soluble material from freeze-pressed bacteria and detergent-eluted material from bacterial envelope were allowed to react in immunodiffusion and immunoelectrophoresis with rabbit antiserum against disintegrated bacteria of the vaccine strain. ten antigenic factors were distinguished in an ether extract. when the extract was precipitated with ammonium sulphate 15 antigenic ... | 1980 | 6153169 |
| glucan-induced enhancement of host resistance to selected infectious diseases. | we conducted studies with mice, rats, and monkeys which demonstrated the ability of glucan to induce either nonspecific or specific enhancement of host resistance to infectious diseases. intravenous pretreatment of mice with glucan significantly enhanced the survival of mice challenged with either venezuelan equine encephalomyelitis (vee) virus or rift valley fever virus. pretreatment was beneficial when initiated 3 days before challenge with vee virus and 7 days before challenge with rift valle ... | 1980 | 7439978 |
| antigen from francisella tularensis: nonidentity between determinants participating in cell-mediated and humoral reactions. | after tularemia vaccinations, most individuals respond with cell-mediated and humoral immunity as disclosed by the lymphocyte stimulation test and enzyme-linked immunosorbent assay (elisa), respectively. there is, however, no correlation between the magnitudes of the two responses, and some individuals show one of the responses only. we now report that the two responses are directed towards different antigenic determinants of the bacterium. ether-water extraction of the live vaccine strain of fr ... | 1984 | 6203835 |
| identification and classification of different isolates of francisella tularensis. | the causative agent of tularemia, francisella tularensis, occurs in two main biovars, the highly virulent f. t. biovar tularensis, found in north america; and the less virulent biovar palaearctica, found all over the northern hemisphere. two other biovars have been proposed, f. t. biovar mediaasiatica and f. t. biovar palaearctica var. japonica. in sweden tularemia is most frequently observed in man and varying hares (lepus timidus), and occasionally in other species. tularemia in hares is norma ... | 1993 | 7510445 |
| [a highly sensitive, homogeneous method for determining antibodies and antigens by using liposomes, monoclonal antibodies and complement]. | a simple and sensitive method for the determination of francisella tularensis antigen and antibodies to this antigen by means of the complement lysis of liposomes sensitized with f. tularensis lipopolysaccharide (lps) is proposed. the possibility of participation of monoclonal antibodies (mcab) in the complement-dependent lysis of liposomes has been studied. the method permits the detection of 50-100 ng/ml of soluble lps antigen in the presence of antiserum or mcab igg f-b11-x and of 50-10 ng/ml ... | 1993 | 7520654 |
| [the determination of the antigenic determinant of protective monoclonal antibodies specific to the francisella tularensis lipopolysaccharide]. | f. tularensis lipopolysaccharide (lps) was studied with the use of monoclonal antibodies (mcab) having protective properties. the binding site of these mcab (igg2a) is localized on the o-chain of lps. in contrast to lps isolated from vaccine strain 15, lps isolated from f. tularensis cells in the r-form has no o-chains and does not interact with mcab. | 1993 | 7520655 |
| nitric oxide: cytokine-regulation of nitric oxide in host resistance to intracellular pathogens. | to discover how nitric oxide (no) synthesis is controlled in different tissues as cells within these tissues combat intracellular pathogens, we examined three distinctively different experimental murine models designed for studying parasite-host interactions: macrophage killing of leishmania major; nonspecific protection against tularemia (francisella tularensis) by mycobacterium bovis (bcg); and specific vaccine-induced protection against hepatic malaria with plasmodium berghei. each model para ... | 1994 | 7537721 |
| electroporation of francisella tularensis. | | 1995 | 7550729 |
| levels of interleukin 6 and tumor necrosis factor in serum from humans vaccinated with live, attenuated francisella tularensis. | the levels of interleukin 6 (il-6) and tumor necrosis factor alpha in serum did not change significantly during the course of immunization with the live vaccine strain of francisella tularensis. higher levels of circulating il-6 were found in the sera of vaccinees with good antibody responses than in the sera from nonresponders. preimmunization levels of il-6 in serum were also higher in responders than in nonresponders. | 1995 | 7583930 |
| seroepidemiologic study of three zoonoses (leptospirosis, q fever, and tularemia) among trappers in québec, canada. | this study was undertaken to evaluate the prevalence of antibodies against francisella tularensis, coxiella burnetii, and certain serovars of leptospira interrogans among trappers in québec, canada. muskrat trapping was identified as a risk factor for f. tularensis infection, whereas having a cat at home apparently protected trappers against infection by l. interrogans. high percentages of control sera were positive for antibodies against c. burnetii (15%) and l. interrogans (5%), most frequentl ... | 1995 | 7583933 |
| [culture properties of the causative agent of tularemia isolated in natural foci in stavropol territory, the kalmyk assr and the armenian ssr]. | the strains isolated in natural foci of the stavropol territory and the armenian ssr have been found to belong to the holarctic race of francisella tularensis, biovar ii. in natural foci of the kalmyk assr the strains belonging to biovars i and ii have been isolated. the study of the tularecinogenicity of the cultures has revealed the existence of strains which are not sensitive to their own tularecins. the phenomenon of tularecinogenicity in f. novocida has been established. avirulent strain 31 ... | 1983 | 6220538 |
| adjuvanticity of iscoms incorporating a t cell-reactive lipoprotein of the facultative intracellular pathogen francisella tularensis. | immunostimulating complexes (iscoms) are known to be highly effective adjuvants for envelope antigens of viral agents, but have not been evaluated for use with antigens of intracellular bacteria. balb/c mice were subcutaneously immunized with iscoms into which the t cell-reactive membrane protein tul4 of francisella tularensis had been incorporated. spleen cells from the immunized mice responded in vitro to tul4 and to heat-killed f. tularensis live vaccine strain (lvs) with proliferation and pr ... | 1995 | 7631511 |
| [detection of the tularemia zoonosis in the territory of the kartlian plain]. | the natural focus of tularemia was found to cover the whole territory of the kartlian plain. epizooty occurred mainly among common voles with the involvement of insectivorous voles. hard ticks, gamasids and fleas infected with francisella tularensis were detected. rodents highly sensitive to tularemia can be affected by this infection. water rats were not involved into the enzootic process. further studies are necessary for the final solution of this problem. | 1983 | 6225274 |
| isolation of francisella tularensis and powassan virus from ticks (acari: ixodidae) in ontario, canada. | | 1984 | 6327984 |
| mixed natural focus of tick-borne encephalitis, tularemia and haemorrhagic fever with renal syndrome in west slovakia. | total of 923 small mammals of 7 species were collected in locality záhorská ves, west slovakia, in 1990-1992. among examined small mammal species it was clethrionomys glareolus (48.7% of total, 17.5% positive for tick-borne encephalitis (tbe) virus antibodies), apodemus flavicollis (29.7% of total, 17.5% positive), a. sylvaticus (11.3% of total, 16.3% positive), and microtus arvalis (6.2% of total, 10.5% positive). the most abundant tick species (larval and nymphal stages) on small mammals was i ... | 1995 | 7676942 |
| an endemic case of tularemia in the mountain hare (lepus timidus) on the island of stora karlsö. | in september 1983, an epizootic of unknown cause broke out among the mountain hares on the island of stora karlsö, which is located outside the coast of gotland. one hare was sent in the national veterinary institute for post-mortem examination. the hare showed lesions in liver, spleen, and bone-marrow typical for tularemia. the specimens were positive for francisella tularensis with fluorescent-antibody test. tularemia has not been observed earlier in this part of sweden. it is supposed that th ... | 1984 | 6393050 |
| cell-mediated and humoral immune responses after vaccination of human volunteers with the live vaccine strain of francisella tularensis. | the specific humoral and cell-mediated immune responses of human volunteers vaccinated with the francisella tularensis live vaccine strain (lvs) were evaluated. in the search for an optimal antigen to measure the immunogenicity of the vaccine in an enzyme-linked immunosorbent assay, we tested irradiation-killed lvs, an aqueous ether extract of the lvs (eex), lipopolysaccharide (lps) from lvs, and a virulent strain (schu4). volunteers were immunized with lvs by scarification. immunoglobulin g (ig ... | 1995 | 7697521 |
| persistence of francisella tularensis mccoy et chapin tularemia agent in the organism of highly sensitive rodents after oral infection. | in the literature there are no data on the possibility of obtaining in experiment non-fatal tularemia infection (persistence) in rodents highly sensitive to it (group i) when using highly virulent strains circulating in nature for infection by natural routes. our detailed experiments on 1483 adult voles microtus rossiaemeridionalis ogn. (syn. m. subarvalis meyer et al.) of laboratory origin using virulent strains of francisella tularensis holarctica ols. et meshch. and natural alimentary infecti ... | 1984 | 6396330 |
| infraspecific taxonomy of tularemia agent francisella tularensis mccoy et chapin. | the authors investigated 286 strains of the tularemia microbe isolated in a number of countries of the old and the new world from humans, hares, rodents, ticks, water and other objects, including 217 strains from the ussr and 69 strains from other countries. as a result, the earlier observed subspecific differences in the biological properties of the tularemia strains isolated in different regions were reconfirmed on an extensive material. it is proposed to designate the three subspecies disting ... | 1982 | 7142690 |
| [isolation and purification of penicillinase from francisella tularensis]. | beta-lactamase was isolated from the cells of a penicillinase-producing strain of the tularemia causative agent. it was purified 100 times. by its properties (the substrate profile, km, temperature optimum and thermostability) beta-lactamase differed from penicillinases isolated from other sources. | 1983 | 6606391 |
| isolation of a francisella tularensis mutant that is sensitive to serum and oxidative killing and is avirulent in mice: correlation with the loss of mind homologue expression. | we constructed mutant strains of francisella tularensis biotype novicida by insertional mutagenesis with a kanamycin resistance (kmr) cassette. one mutant, kem7, was defective for survival in macrophages in comparison with the wild-type (wt) strain and a random insertion strain, kem21. while all three strains exhibited intracellular growth, the number of viable kem7 present after 24-48 h of infection was approximately 10 times less than that of wt or kem21. this observation was apparently due to ... | 1994 | 7813885 |
| tularaemia transmitted by ticks (dermacentor andersoni) in saskatchewan. | common wood ticks (dermacentor andersoni) collected from saskatchewan landing provincial park, saskatchewan in the spring of 1982 transmitted a lethal tularaemia infection to four of six rabbits. francisella tularensis organisms were isolated from tissues taken from the dead rabbits and identified from subcultures using an indirect immunofluorescent antibody assay. one human associated with the animals developed symptoms of tularaemia and, after successful therapy, had a significant increase in ... | 1983 | 6667429 |
| [transstadial transmission of francisella tularensis by ixodes ricinus ticks infected during the nymphal stage]. | the degree of infection of nymphs of ixodes ricinus which finished their feeding on experimentally infected mice on the day of their death from tularaemia represented more than 10(7) cells of francisella tularensis per tick after feeding. the high degree of positivity was preserved in ticks also during one month of metamorphosis. transstadial transmission of the agent from the stage of nymph to the stage of imago was confirmed in adults either by cultivation or by experiments attempting to trans ... | 1994 | 7850217 |
| [an immunological analysis of bacterial persistence in the bone marrow]. | a method for the evaluation of bacterial persistence in the bone marrow in association with particular clonogenic target cells was developed. the method was based on the negative selection of cells expressing microbial antigens after treatment with hyperimmune antiserum specific to a given infective agent and the subsequent quantitation of target cells thus eliminated in appropriate assays. using this approach, we demonstrated that mycoplasma arthritidis and l-forms of streptococcus strain l-406 ... | 1994 | 7856346 |
| [results of the study of bird droppings collected in the lithuanian ssr for the purpose of searching out tularemia epizootics]. | there are practically no records of cases of tularemia among humans in the lithuanian ssr. nevertheless, the mass sero-allergic survey of the population for tularemia, carried out 10-12 years ago, showed that 2.3% of the adult population in the republic had had contacts with the causative agent of this infection. the work was aimed at the determination of the present activity of the foci of tularemia. during 6 years in 22 rural districts 2582 samples of avian excrements, containing bones and woo ... | 1984 | 6711197 |
| increased synthesis of dnak, groel, and groes homologs by francisella tularensis lvs in response to heat and hydrogen peroxide. | the response of the facultative intracellular bacterium francisella tularensis lvs to stress was assayed by pulse-labeling with [35s]methionine followed by two-dimensional gel electrophoresis and autoradiography. a temperature increase from 37 to 42 degrees c or exposure to 5 mm hydrogen peroxide induced increased syntheses of at least 15 proteins. among these proteins were a 75-, a 60-, and a 10-kda protein. by n-terminal sequence analysis, these three proteins were found to be extensively homo ... | 1994 | 7903283 |
| reduced virulence of rifampicin-resistant mutants of francisella tularensis. | rifampicin-resistant mutants of a live vaccine strain (lvs) of francisella tularensis were produced and screened for virulence in mice; 4 avirulent clones with intraperitoneal (ip) ld50s > 10(6) cfu, compared with 10(2) cfu for lvs, were characterized. growth characteristics at 37 degrees c, surface envelope proteins, and lipopolysaccharide profiles of resistant mutants were identical to those of lvs. polymerase activity of the mutants was more resistant than the enzyme from lvs to the inhibitor ... | 1994 | 7930725 |
| survey for selected diseases in nutria (myocastor coypus) from louisiana. | thirty-two trapper-caught nutria (myocastor coypus) from east baton rouge, iberville, tangipahoa, and st. helena parishes in louisiana (usa) were sampled for several disease agents. antibodies against toxoplasma gondii, chlamydia psittaci, francisella tularensis, leptospira spp., and encephalomyocarditis virus were detected in 7%, 14%, 0%, 7%, and 0% of nutria, respectively. both animals seropositive for leptospirae were positive for l. interrogans serovar canicola. no salmonella spp. were isola ... | 1994 | 7933295 |
| [the effect of the antigenic fractions of the outer membrane of francisella tularensis on the t-cell immunity indices]. | the immunological evaluation of the influence of individual gel-chromatographic antigenic fractions (gaf) of f. tularensis outer membrane on different forms of t-cell reactiveness, such as delayed hypersensitivity (dh), proliferation of lymphocytes in the reaction of blast transformation (rbt) and mixed lymphocyte culture (mlc), has been made. as revealed in this study, gaf isolated from f. tularensis produce a pronounced immunomodulating effect on the processes linked with polyclonal activation ... | 1994 | 7941852 |
| [the search for and isolation of an antiphagocytic factor in francisella tularensis]. | in this study a search for f. tularensis antiphagocytic factor and an attempt for its isolation were made. for this purpose a fraction of f.tularensis water-saline extract saturated 55-60% with ammonium sulfate was split into separate components by preparative methods. one of them, consisting of two antigens of glycoprotein nature, had the capacity of decreasing the digestion of f.tularensis by guinea pig peritoneal macrophages about 10 times. the study revealed that the protein of the preparati ... | 1994 | 7941862 |
| phagocytosis and killing of francisella tularensis by human polymorphonuclear leukocytes. | bacteria of a wild strain of francisella tularensis were less efficiently killed by human polymorphonuclear leukocytes than were bacteria of an attenuated strain. this finding was explained to some extent by a less efficient phagocytosis, but bacteria of the wild strain also seemed to be more resistant to killing after ingestion. | 1983 | 6832815 |
| streptomycin and alternative agents for the treatment of tularemia: review of the literature. | because of the recent lack of availability of streptomycin--currently considered the drug of choice for the treatment of tularemia--we reviewed the literature on alternative drugs that have been used for this purpose. in addition, we reviewed data on the in vitro susceptibility of francisella tularensis to a wide variety of agents. the rate of cure for streptomycin was 97%, with no relapses. for gentamicin and tetracycline, respectively, the rates of cure were 86% and 88%, the rates of relapse w ... | 1994 | 7948556 |
| cd4+ and cd8+ t-cell-dependent and -independent host defense mechanisms can operate to control and resolve primary and secondary francisella tularensis lvs infection in mice. | immunity to experimental infection with the facultative intracellular bacterium francisella tularensis is generally considered an example of t-cell-mediated, macrophage-expressed immunity. however, the results of the present study indicate that t-cell-independent mechanisms are also important in anti-francisella defense. they show that mice selectively depleted of cd4+, cd8+, or both t-cell populations by treatment with t-cell subset-specific monoclonal antibodies remained capable of controlling ... | 1994 | 7960142 |
| increased encapsulation and virulence of francisella tularensis live vaccine strain (lvs) by subculturing on synthetic medium. | francisella tularensis live vaccine strain (lvs), taken directly from lyophilized vials, did not appear to have a capsule and had low virulence for balb/c mice. when this strain was subcultured on chamberlain's synthetic medium (ph 6.5), it became extensively capsulated (1-5 micron in diameter) and its virulence for balb/c mice increased about 1000-fold. we conclude that the virulence of the attenuated vaccine strain, f. tularensis lvs, may still be influenced by growth conditions. | 1994 | 7975855 |
| [europium-labelled staphylococcus aureus protein a as a reagent for determining specific antibodies]. | in this work the conditions of labeling protein a with europium ions were studied and the conjugates obtained in this study were compared with traditional peroxidase conjugates currently used in immunochemistry. the conjugates of protein a with eu3+ chelate were obtained with the use of cyclic dianhydride of diethylenetriaminepentaacetic acid (dadetpa). conjugation methods with the use of dadetpa was shown to permit obtaining high-quality conjugates with europium chelates. europium-labeled prote ... | 1994 | 7992539 |
| a serological survey of antibodies against francisella tularensis in some swedish mammals. | tularemia occurs in sweden as an epizootic among the mountain hare. little is known about the occurrence of the disease in other animals in this country. for this reason serum samples from 28 cattle, 83 moose, 110 beavers and 97 mountain hares were investigated for the presence of antibodies against francisella tularensis. the antibody levels against f. tularensis found in moose and cattle were generally low and also in a low incidence. this indicates that these species are not susceptible to tu ... | 1983 | 6878028 |
| persistence of cell-mediated immunity and decline of humoral immunity to the intracellular bacterium francisella tularensis 25 years after natural infection. | the humoral and cell-mediated immune responses to the facultative intracellular pathogen francisella tularensis were studied in subjects who had tularemia 25 years earlier. serum agglutinin titers were low. of 53 subjects, only 2 had a titer > 40. the f. tularensis-induced t cell response, on the other hand, was vigorous and in fact similar in magnitude to the response to purified protein derivative (ppd) of mycobacterium tuberculosis. t cells from 44 of 52 subjects showed a significant (p < .05 ... | 1994 | 8014484 |
| [development of a serological micromethod for the detection of antibodies against francisella tularensis]. | | 1980 | 6982628 |
| transfer of immunity against lethal murine francisella infection by specific antibody depends on host gamma interferon and t cells. | both serum and spleen cells from mice immune to francisella tularensis transfer protection to naive recipients. here we characterize the mechanism of protection induced by transfer of immune mouse serum (ims). ims obtained 4 weeks after intradermal infection with 10(3) bacteria of the live vaccine strain (lvs) contained high levels of immunoglobulin g2 (igg2a) and igm (end point titers, 1:16,600 and 1:7,200, respectively) and little igg1, igg2b, or igg3. lvs-specific antibodies were detected 5 d ... | 1994 | 8039881 |
| [biological activity of lysozymes of various origins]. | the in vitro and in vivo studies showed that lysozymes obtained from o. papillipes, o moubata, a. lahorensis and h. asiaticum had bacteriostatic and bactericidal effects. the effect of the lysozymes obtained from the above ticks was studied in comparison to that of the egg lysozyme. micrococci, staphylococci, streptococci, e. coli and c. diphtheriae proved to be the most sensitive. salmonella, listeria, pasteurella pseudotuberculosis and pasteurella tularensis were less sensitive. the comparison ... | 1982 | 7149682 |
| a probable endocrine basis for the depression of ketone bodies during infectious or inflammatory state in rats. | the effects of infection with streptococcus pneumoniae, francisella tularensis, and venezuelan equine encephalitis virus as well as inflammatory stress induced by the administration of turpentine and endotoxin on plasma ketone bodies and insulin were studied in white rats. all of the infectious/inflammatory stresses caused a significant decrease in the ketonemia of fasting and an elevation of plasma insulin. when a pneumococcal infection was initiated in a diabetic rat, inhibition of fasting ket ... | 1980 | 6993191 |
| lipoarabinomannan from mycobacterium tuberculosis modulates the generation of reactive nitrogen intermediates by gamma interferon-activated macrophages. | lipoarabinomannan derived from the virulent erdman strain and a rapidly growing, laboratory-attenuated strain of mycobacterium tuberculosis were evaluated for their ability to modulate the production of nitric oxide (no) by macrophages activated with ifn-gamma or ifn-gamma and lps. it was observed that in macrophages pretreated with 100 micrograms ml-1 lam, the no induced by ifn-gamma alone was augmented while the no induced ifn-gamma and lps was reduced. lam was also shown to synergize with ifn ... | 1994 | 8061654 |
| demonstration of opsonizing antibodies to francisella tularensis by leukocyte chemiluminescence. | twenty-three individuals were vaccinated with a viable attenuated strain of francisella tularensis, and blood was collected at various time intervals during 4 weeks. to demonstrate opsonizing antibodies, a mixture of serum and vaccine bacteria was incubated, whereafter the chemiluminescence response of polymorphonuclear (pmn) leukocytes to this mixture was recorded. no opsonizing antibodies against f. tularensis were found in sera obtained before vaccination. eleven days after vaccination, sera ... | 1980 | 7216416 |
| [the effect of antigenic fractions of the outer membrane in francisella tularensis on the functional activity of macrophages]. | the influence of different gel-chromatographic antigenic fractions (gaf) of the membrane of f. tularensis, strain a'cole, on different forms of reactivity of mouse peritoneal macrophages, such as the adhesion, ingestion and presentation of antigen on the cell surface, has been immunologically evaluated. gaf isolated from f. tularensis have been shown to produce a pronounced modulating effect on all forms of macrophagal functional activity under study. thus, gaf ii with a molecular weight of 85-2 ... | 1993 | 8067125 |
| tularemia: treatment failures with outpatient use of ceftriaxone. | tularemia, an infection caused by the coccobacillus francisella tularensis, can be a difficult disease process to diagnose and treat. the difficulty in treating this disease is related to the pathophysiology of the infection and the toxicity of the antimicrobial agents presently recommended for treatment. recent in vitro data have suggested that antimicrobial drugs other than standard agents (streptomycin, gentamicin, chloramphenicol, or tetracycline) may be effective. we present eight cases of ... | 1993 | 8110955 |
| differential alterations in host peripheral polymorphonuclear leukocyte chemiluminescence during the course of bacterial and viral infections. | previous studies have shown that stimulation of the oxidative metabolism in polymorphonuclear leukocytes (pmn) by in vitro phagocytosis of various microorganisms results in photon emission, termed chemiluminescence (cl). studies were conducted to determine whether bacterial and viral infections induce enhanced basal endogenous host peripheral pmn cl in the absence of in vitro phagocytic stimulation. nonimmune rats and guinea pigs as well as immune rats were inoculated with various doses (10(5) t ... | 1980 | 7228389 |
| early recognition of atypical francisella tularensis strains lacking a cysteine requirement. | seven cultures referred to in our laboratories as unidentified gram-negative bacilli or haemophilus species were identified as atypical strains of francisella tularensis lacking a requirement for cysteine or enriched medium for growth. the use of cellular fatty acid composition analysis facilitated early recognition of this pathogen and prompt implementation of appropriate biosafety measures. | 1994 | 8150973 |
| case report. tularemia in ohio: report of two cases and clinical review. | although unusual, human tularemia continues to be reported from areas of the united states which are not heavily endemic for the disease. two patients with ulceroglandular tularemia diagnosed in ohio are described. the causative microorganism, francisella tularensis, is a small, pleomorphic gram negative coccobacillus which requires special microbiological media for laboratory isolation. in nature, the organism is usually transmitted to man by the handling of infected animal tissues and body flu ... | 1981 | 7315867 |
| life and death of an intracellular pathogen: francisella tularensis and the macrophage. | | 1994 | 8251580 |
| a serologic survey for some bacterial and viral zoonoses in game animals in the czech republic. | between 1986 and 1991, sera were collected from 33 roe deer (capreolus capreolus), 24 red deer (cervus elaphus), four fallow deer (dama dama), two mouflon (ovis musimon), 34 wild boars (sus scrofa), and 48 hares (lepus europaeus) shot in two areas of the czech republic. collectively, the sera contained antibodies to coxiella burnetii (prevalence of 12%), francisella tularensis (4%), brucella spp. (2%), central european tick-borne encephalitis virus (8%), tahyna (california serogroup) virus (36%) ... | 1993 | 8258864 |
| cell-mediated immunity against francisella tularensis after natural infection. | 31 subjects with tularemia recently or up to 11 years earlier were studied for cell-mediated immunity against francisella tularensis using formalin-killed bacteria as antigen in the lymphocyte blast transformation test. lymphocytes from all the subjects responded to f. tularensis antigen both in separated mononuclear cell and whole blood cultures, whereas lymphocytes from 12 controls responded not at all or only weakly to hig antigen concentrations and only in separated mononuclear cell cultures ... | 1980 | 7006062 |
| the entry and intracellular multiplication of francisella tularensis in cultured cells: its correlation with virulence in experimental mice. | five acriflavine agglutination test-positive (acf+) colonies and five negative (acf-) colonies were isolated from each of the four strains (ebina, cmb2, n9, and schu) of francisella tularensis, and the correlation between the virulence in experimental mice and the entry and intracellular multiplication in cultured mouse fibroblast cells (l-929 cells) was examined. all of the acf- colonies derived from the ebina and cmb2 strains were highly virulent in mice, readily entering and growing well in t ... | 1993 | 8295562 |
| mechanisms of protective immunogenicity of microbial vaccines: effects of cyclophosphamide pretreatment in venezuelan encephalitis, q fever and tularaemia. | administration of high-dose (250 mg/kg) cyclophosphamide (cy) to guinea-pigs and mice 3 days prior to immunization with inactivated vaccine derived from venezuelan encephalitis virus (ve), coxiella burnetii and francisella tularensis resulted in accentuated and prolonged delayed-type hypersensitivity (dth) and in vitro cellular immunity (cmi) to specific antigen. humoral antibody were either absent or significantly lower in cy-pretreated animals compared to immunized non-pretreated controls. cy ... | 1980 | 7438552 |
| [transstadial transmission of francisella tularensis in the tick, ixodes ricinus, infected during the larval stage]. | based on previous studies which proved the decisive importance of the degree of bacteraemia of experimentally infected white mice for the degree of infection of ticks ixodes ricinus the authors confirmed the possibility of transstadial transmission of francisella tularensis from larvae via nymphs to imagos by the detection of germs in the ticks and by experiments attempting their transmission to white mice. this applied to imagos even one year after the infection of larvae. transmission was reco ... | 1993 | 8348625 |
| use of immunoelectron microscopy to demonstrate francisella tularensis. | three immunoelectron microscopy (iem) methods were employed to show laboratory-cultivated francisella tularensis. by the iem assays, f. tularensis was distinguished from four antigenically distinct gram-negative bacteria. iem should be a valuable tool for confirming presumptive isolates of f. tularensis and may potentially be useful for demonstrating other medically important bacteria. | 1993 | 8349780 |
| liposome-encapsulated ciprofloxacin is effective in the protection and treatment of balb/c mice against francisella tularensis. | | 1993 | 8354928 |
| influence of complement on the chemiluminescent response of human leukocytes to immune complex. | vaccine bacteria of francisella tularensis were mixed with human serum containing specific antibodies against the same organism, and the mixture was incubated at 37 degrees c for 30 min. the mixture induced a two-peak chemiluminescent response in polymorphonuclear leukocytes. the initial peak was induced by a soluble agent, formed during incubation. the formation of this agent involved the activation of complement component c5. the second peak of the chemiluminescent response was induced by the ... | 1980 | 7011971 |
| analysis of a cloned francisella tularensis outer membrane protein gene and expression in attenuated salmonella typhimurium. | we have determined the nucleotide sequence of fopa from francisella tularensis. using the polymerase chain reaction fopa was detected in high and low virulence biotypes of f. tularensis. fopa was stably maintained in pbluescript in attenuated salmonella typhimurium where fopa was expressed and located in the outer membrane. this recombinant will be suitable for studies on the role of fopa in immunity against tularaemia. | 1993 | 8405941 |
| tularemia in canada with a focus on saskatchewan. | although rare among humans in canada, tularemia is often endemic in wildlife. the inhabitants of rural areas are especially likely to be exposed to the causative bacterium, francisella tularensis, through trapping or through the bites of arthropods. muskrats have replaced rabbits as the principal source of infection, as illustrated by a familial outbreak of oropharyngeal tularemia in saskatchewan. in humans the disease has six distinct forms and can be asymptomatic, but it generally comes to med ... | 1982 | 7046896 |
| antibodies to francisella tularensis in the snowshoe hare (lepus americanus struthopus) populations of nova scotia and prince edward island and in the moose (alces alces americana clinton) population of nova scotia. | | 1982 | 7093820 |
| neutralization of gamma interferon and tumor necrosis factor alpha blocks in vivo synthesis of nitrogen oxides from l-arginine and protection against francisella tularensis infection in mycobacterium bovis bcg-treated mice. | peritoneal cells from mycobacterium bovis bcg-infected c3h/hen mice produced nitrite (no2-, an oxidative end product of nitric oxide [no] synthesis) and inhibited the growth of francisella tularensis, a facultative intracellular bacterium. both no2- production and inhibition of bacterial growth were suppressed by ng-monomethyl-l-arginine, a substrate inhibitor of nitrogen oxidation of l-arginine, and monoclonal antibodies (mabs) to gamma interferon (ifn-gamma) and tumor necrosis factor alpha (tn ... | 1993 | 8423095 |
| cell-mediated and humoral immunity induced by a live francisella tularensis vaccine. | live attenuated francisella tularensis vaccine induced long-lasting humoral and cell-mediated immune responses in all 13 subjects studied. lymphocyte blast transformation reactivity to f. tularensis appeared 2 weeks after vaccination in most subjects and remained unchanged for up to 1.5 years. similarly, in most recipients, antibodies against f. tularensis were detectable by both the enzyme-linked immunosorbent assay (elisa) and the agglutination method from 2 weeks after vaccination, although d ... | 1982 | 7095859 |
| t-cell-independent resistance to infection and generation of immunity to francisella tularensis. | the intraperitoneal 50% lethal dose (ld50) for francisella tularensis lvs in both normal control heterozygote balb/c nu/+ mice and balb/c nu/nu mice was 2 x 10(0). both nu/+ and nu/nu mice given 10(7) lvs bacteria or more intradermally (i.d.) died, with a mean time to death of about 7 to 8 days. on the other hand, nu/+ mice given 10(6) lvs bacteria or less survived for more than 60 days and cleared systemic bacteria, while nu/nu mice given 10(6) lvs bacteria or less survived for more than 10 day ... | 1993 | 8432603 |
| [the glycolipid composition of francisella tularensis strains with different degrees of attenuation]. | the glycolipid composition of f. tularensis strains was investigated by silica gel thin-layer chromatography. vaccine strains in contrast to virulent ones lacked glycolipid 8, possessed new glycolipid 8-a and a higher level of glycolipid 7. low immunogenic strains had a decreased content of glycolipids, while avirulent non-immunogenic strain (15-a) nearly completely lost them. thus, the glycolipid composition is associated with the level of attenuation, virulence and immunogenicity of f. tularen ... | 1993 | 8446062 |
| nodular lymphangitis: a distinctive but often unrecognized syndrome. | to describe nodular lymphangitis by reviewing the clinical and epidemiologic features of this disease with an emphasis on distinguishing specific etiologic agents. | 1993 | 8480962 |
| comparative analysis of antibodies to francisella tularensis antigens during the acute phase of tularemia and eight years later. | approximately 8 years after treatment for tularemia, 14 of 22 (63.6%) individuals tested still had a positive microagglutination test for francisella tularensis antibodies. an enzyme-linked immunosorbent assay for anti-f. tularensis outer membrane antibodies was positive for 55% (immunoglobulin a [iga]), 95% (igg), and 27% (igm) of the late-phase sera, but with antibody levels significantly reduced from those in the acute-phase sera. igg and iga antibody levels in the late-phase sera showed sign ... | 1994 | 7496953 |
| heat stress alters the virulence of a rifampin-resistant mutant of francisella tularensis lvs. | we have studied the stress response of a rifampin-resistant mutant of francisella tularensis lvs. this mutant, rif 7, was avirulent with an intraperitoneally administered 50% lethal dose greater than 10(7) cfu in a murine model of infection. exposure of rif 7 to heat stress for 5 h in vitro resulted in a 2-log decrease in its 50% lethal dose (p < 0.02). the increase in virulence was dependent on the time of exposure to high temperature and was maximal at 5 h. envelope preparations from heat-stre ... | 1995 | 7806352 |
| cytokine expression in the liver during the early phase of murine tularemia. | cytokine expression was determined in the livers of mice inoculated subcutaneously with francisella tularensis lvs. during the first 48 h of infection, there was a logarithmic increase of bacteria in the liver, with a doubling time of 2.5 h. within 48 h, tumor necrosis factor alpha (tnf-alpha), interleukin 10 (il-10), il-12, and gamma interferon (ifn-gamma) mrnas were expressed, and production of tnf-alpha and ifn-gamma was demonstrated. there was no expression within 96 h of mrna from il-2, il- ... | 1995 | 7822019 |
| growth of francisella tularensis lvs in macrophages: the acidic intracellular compartment provides essential iron required for growth. | murine macrophages supported exponential intracellular growth of francisella tularensis lvs in vitro with a doubling time of 4 to 6 h. lvs was internalized and remained in a vacuolar compartment throughout its growth cycle. the importance of endosome acidification to intracellular growth of this bacterium was assessed by treatment of lvs-infected macrophages with several different lysosomotropic agents (chloroquine, nh4cl, and ouabain). regardless of the agent used or its mechanism of action, ma ... | 1995 | 7890413 |
| [the immunological efficacy of francisella tularensis outer membranes for hamadryas baboons]. | the protective properties of the preparation of f. tularensis outer membranes (om), obtained from f. tularensis vaccine strain 15, were studied in experiments on hamadryas baboons challenged subcutaneously with f. tularensis virulent strain schu (nonarctic subspecies). the subcutaneous immunization with the om preparation prevented the development of clinically pronounced infection in more than 70% of the monkeys challenged with f. tularensis strain schu in a dose of 787 live microbial cells 30 ... | 1994 | 7941871 |
| prevalence of ticks infected with francisella tularensis in natural foci of tularemia in western slovakia. | the prevalence of ticks infected with f. tularensis was followed during a systematic surveillance in endemic area of tularemia in western slovakia over the years 1984-93. ticks were collected from vegetation in localities of podunajské biskupice, in the vicinity of the capital of slovakia, bratislava, near the river danube. in total 6033 ticks, mostly adults of dermacentor reticulatus and ixodes ricinus (4994 and 1004, respectively) and 35 nymphs of haemaphysalis concinna, were examined for the ... | 1995 | 8549717 |
| role of lipopolysaccharide and a major outer membrane protein from francisella tularensis in the induction of immunity against tularemia. | a crude outer membrane preparation from francisella tularensis live vaccine strain (lvs) was used to immunize mice. immunized mice were completely protected from a f. tularensis challenge. we evaluated the role of two major outer membrane antigens in the induction of protective immunity, namely lipopolysaccharide and an outer membrane protein fopa. we presented fopa to the immune system using an aromatic amino acid-dependent salmonella typhimurium as a vector. although mice mounted an immune res ... | 1995 | 8578807 |
| a rapid, highly sensitive method for the detection of francisella tularensis in clinical samples using the polymerase chain reaction. | we have developed a highly sensitive method for detection of francisella tularensis in clinical samples based on a nested polymerase chain reaction (pcr) for the fopa gene. mice infected with f. tularensis were killed at 24-hr intervals, and the dna from blood and spleens was extracted by a variety of methods and analyzed by pcr. the best method, based on the ability of dna to bind to silica in the presence of guanidine thiocyanate, yielded amplifiable dna without dilution of the murine tissue s ... | 1996 | 8615448 |
| neutrophils are critical for host defense against primary infection with the facultative intracellular bacterium francisella tularensis in mice and participate in defense against reinfection. | it is generally believed that immunity to experimental infection with the facultative intracellular bacterium francisella tularensis is an example of t-cell-mediated immunity that is expressed by activated macrophages and mediated by francisella-specific t cells. according to the results presented herein, neutrophils are also essential for defense against primary infection with this organism. it is shown that mice depleted of neutrophils by treatment with the granulocyte-specific monoclonal anti ... | 1994 | 8005668 |
| ixodes (ixodes) scapularis (acari:ixodidae): redescription of all active stages, distribution, hosts, geographical variation, and medical and veterinary importance. | the blacklegged tick, ixodes (ixodes) scapularis say, 1821, is redescribed, based on laboratory reared specimens originating in bulloch county, georgia. information on distribution, host associations, morphological variation, and medical/veterinary importance is also presented. a great deal of recent work has focused on this species because it is the principal vector of the agent of lyme disease (borrelia burgdorferi johnson, schmidt, hyde, steigerwaldt & brenner) in eastern north america. its d ... | 1996 | 8667375 |
| nitric oxide-independent killing of francisella tularensis by ifn-gamma-stimulated murine alveolar macrophages. | alveolar macrophages (ams) were analyzed for ability to support replication of the intracellular bacterium francisella tularensis live vaccine strain (lvs). am supported in vitro growth (2 to 3 logs over 5 days) of lvs with a doubling time of 8 +/- 0.8 h. ams were analyzed for responsiveness to rifn-gamma for destruction of this lung pathogen. am treated with 50 u/ml rifn-gamma allowed early growth of bacteria (six doublings over 48 h) but between 48 and 96 h rifn-gamma-treated am eliminated 1.5 ... | 1994 | 8027551 |
| [the capacity of avirulent forms of francisella tularensis for dissemination and proliferation in the host body]. | in this investigation isogenic avirulent variants obtained from f. tularensis standard virulent strain 503 were used. the capsule-deficient variants (cap-) were shown to have no species-specific capsular antigens and to be capable of producing r-lps having no the polysaccharide part of the molecules. the capsule-defective forms (cap +/- ) were found to synthesize capsular antigens and s-lps whose polysaccharide part essentially differed from the o-lateral chains of lps of the virulent strain. th ... | 1996 | 8701638 |
| [francisella tularensis persistence in the body of highly sensitive animals]. | | 1996 | 8701641 |
| [the characteristics of a natural attenuated isolate of francisella tularensis]. | the natural isolate of f. tularensis subsp. holarctica 268 was detected and studied. the isolate possessed the properties of the vaccine strain: residual virulence for white mice, avirulence for guinea pigs and high immunogenicity for experimental animals. a significant decrease in its virulence for animals, highly sensitive to tularemia, was noted. in contrast to most virulent strains circulating in natural foci, f. tularensis strain 268 was characterized by the absence of growth at a cultivati ... | 1996 | 8701651 |
| passive protection of mice against lethal francisella tularensis (live tularemia vaccine strain) infection by the sera of human recipients of the live tularemia vaccine. | the relative role that humoral immunity plays in protection against infection with the intracellular bacterium, francisella tularensis, remains controversial. cellular immunity is thought to play the major and perhaps only role. the authors, in this article, investigate the immunologic and protective properties of immune serum collected from human recipients of the live tularemia vaccine (lvs). sera of recipients of the vaccine demonstrated reactivity with the vaccine strain by enzyme-linked imm ... | 1994 | 8042659 |
| [the presence of antibodies against francisella tularensis among inhabitants of north-eastern poland]. | in this work we analysed the frequency of incidence of antibodies against f. tularensis among forest workers in region of north-eastern poland. the presence was detected in 0,13% analised workers and 3,38% hospitalised patients in clinic of parasitic diseases and neuroinfections in białystok. | 1996 | 8711161 |
| lack of requirement for prolonged incubation of septi-chek blood culture bottles in patients with bacteremia due to fastidious bacteria. | a questionnaire survey for which there were 538 respondents from american clinical microbiology laboratories was used to assess the need for prolonged incubation of septi-chek blood culture bottles for the recovery of hacek bacilli, brucella species, francisella tularensis, and nutritionally deficient streptococci from blood. among a total of 219 reported isolates of these bacteria, in only 6 cases (2.7%) was incubation longer than 7 days required. only 2 of 136 patients (1.5%) were noted to be ... | 1996 | 8724399 |
| [the isolation of capsule-free variants of francisella tularensis]. | new methods (selection in medium t with 20% tween-80, inducing mutations leading to the appearance of resistance to triphenyl tetrazolium chloride or indoxyl phosphate) helped create a collection of f. tularensis stable non-capsular variants from strains of different subspecies. the characteristic features of all f. tularensis cap- variants include inability to serologic tests with erythrocytic diagnosticum, the absence of capsular antigens, sensitivity to normal human serum. | 1993 | 8059577 |
| correlation of the polysaccharide antigens of francisella tularensis with virulence in experimental mice. | francisella tularensis gives rise to two distinct colony types, acriflavine agglutination test-positive (acf+) and -negative (acf-) colonies. the acf+ variants were exclusively low virulent in mice, while the acf- variants were shown to be either high or low virulent. three fractions, phosphate-buffered saline-extractable without heating, with heating at 60 c, and with heating at 100 c, were obtained from cultures of both the acf+ and acf- variants on agar media, and the polysaccharide antigens ... | 1995 | 8789061 |
| [the characteristics of the biological properties of capsule-free variants of francisella tularensis]. | comparative study of the properties of initial capsular (cap+) and non-capsular (cap-) f. tularensis strains has revealed that the non-capsular variants have their specific biological features. the characteristic features of these variants are avirulence and inability to produce an immunogenic effect in sensitive laboratory animals. cap- mutants, depending on the method of their obtaining, may exhibit different sensitivity to some antibacterial preparations. in contrast to the initial virulent s ... | 1993 | 8067085 |
| isolation of francisella tularensis from lymph node aspirate inoculated into a non-radiometric blood culture system. | | 1996 | 8801096 |
| analysis of 16s ribosomal dna sequences of francisella strains and utilization for determination of the phylogeny of the genus and for identification of strains by pcr. | the 16s ribosomal dnas (rdnas) of two strains of francisella tularensis and one strain of francisella philomiragia were sequenced. on the basis of phylogenetic analysis data, the genus francisella was placed in the gamma subclass of the proteobacteria. the most closely related organism was the intracellular bacterium wolbachia persica. the sequenced 16s rdna molecules of the francisella species exhibited very high levels of similarity (98.5 to 99.9%). two variable regions, comprising 390 to 450 ... | 1994 | 8123561 |
| characterization of two unusual clinically significant francisella strains. | we have isolated two phenotypically distinct nonfastidious francisella strains (fx1 and fx2) from the blood of compromised patients with pneumonia and compared them with eight other francisella strains, including francisella tularensis biovar tularensis, f. tularensis biovar novicida, and f. philomiragia. our isolates grew well on sheep blood agar, chocolate agar, modified thayer-martin agar, and trypticase soy agar. fx1 and fx2 were determined to be within the francisella genus by cellular fatt ... | 1996 | 8818897 |
| [the resistance of francisella tularensis to the bactericidal action of normal serum as a criterion for evaluating the virulence of the bacterium]. | the study of the sensitivity of f. tularensis to the bactericidal action of normal serum (ns) revealed that all virulent cultures were resistant, while avirulent cultures were highly sensitive to ns. the synthesis of r-lipopolysaccharide (lps) by capsule-deficient (cap-) clones or the synthesis of s-lps by capsule-defective (cap+/-) clones of the avirulent phenotype of these bacteria had no influence on the sensitivity of these forms to ns, but ensured longer survival of cap+/- variants in the s ... | 1996 | 8820667 |
| parasites and selected diseases of collared peccaries (tayassu tajacu) in the trans-pecos region of texas. | fifty-five collared peccaries (tayassu tajacu) were collected from october 1988 through april 1991 from five counties within the trans-pecos region of texas (usa) to monitor for diseases and parasites. no endoparasites were recovered on gross examination. antibody to borrelia burgdorferi was documented in one (2%) of 55 specimens. three (6%) of 54 collared peccaries were positive for yersinia pestis antibodies. all collared peccaries were negative for antibodies against brucella spp., francisell ... | 1996 | 8827690 |
| [the protective properties of the outer membranes of francisella tularensis in an experimental infection in guinea pigs]. | subcutaneous immunization, made in a single injection, with outer membrane preparations obtained from f.tularensis vaccine strain 15 and virulent strain a'cole results in intensive immunity to tularemia in guinea pigs, ensuring the protection of 60-100% of the animals within a month after challenge with f.tularensis virulent strain 503 in a dose of 1,000 dcl. the development of protective effect induced by f.tularensis outer membranes can be observed during the first 24 hours and reaches its max ... | 1994 | 8184621 |