| macrophage control of brucella abortus: role of reactive oxygen intermediates and nitric oxide. | macrophages infected with brucella abortus are able to kill intracellular brucellae over the first 12 to 24 hr following infection. thereafter, the surviving brucellae replicate. we have shown previously that macrophages activated with interferon-gamma (ifn-gamma) have enhanced brucellacidal and brucellastatic activities. in studies reported here, treatment of macrophages with methylene blue, an electron carrier, enhanced the initial killing of intracellular brucellae, indicating their susceptib ... | 1993 | 8402938 |
| endogenous gamma interferon mediates resistance to brucella abortus infection. | depletion of endogenous gamma interferon (ifn-gamma) with anti-ifn-gamma monoclonal antibody resulted in increased numbers of brucella abortus in the spleen and liver of infected cba mice. this increase was accompanied by a decrease in splenomegaly and a lower proportion of macrophages in the spleen. furthermore, treatment of recipient mice with anti-ifn-gamma antibody blocked the adoptive transfer of resistance with immune t cells. together, the results indicated that endogenous ifn-gamma plays ... | 1993 | 8406893 |
| effects of cytokines on intracellular growth of brucella abortus. | interleukin 1 alpha (il-1 alpha), il-2, il-4, il-6, gamma interferon (ifn-gamma), tumor necrosis factor alpha (tnf-alpha), and granulocyte macrophage colony-stimulating factor (gm-csf) were tested for their abilities to alter the growth of brucella abortus in balb/c j774a.1 murine macrophages. il-1 alpha, il-4, il-6, tumor necrosis factor alpha, and granulocyte macrophage-colony-stimulating factor had no consistent or significant effect on the growth of the avirulent b. abortus strain 19. in con ... | 1993 | 8418034 |
| oral immunization of mice and swine with an attenuated salmonella choleraesuis [delta cya-12 delta(crp-cdt)19] mutant containing a recombinant plasmid. | salmonella choleraesuis chi 3781, an attenuated [delta cya-12 delta(crp-cdt)19] mutant, was electroporated with the plasmid pba31-r7, which codes for the expression of a 31-kda protein from brucella abortus (bcsp31). recombinant s. choleraesuis chi 3781 stably maintained the pba31-r7 plasmid and continued to express the cloned protein following recovery of the organism from orally inoculated animals. unlike previous studies using s. typhimurium chi 4064(pba31-r7), s. choleraesuis chi 3781(pba31- ... | 1993 | 8423090 |
| comparative analysis of using mtt and xtt in colorimetric assays for quantitating bovine neutrophil bactericidal activity. | two different tetrazolium compounds were compared for use in a colorimetric assay for quantitating bovine neutrophil bactericidal activity against staphylococcus aureus, escherichia coli, listeria monocytogenes, and brucella abortus. the tetrazolium compounds tested included 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (mtt) and sodium 3,3'-[1[(phenylamino)carbonyl]-3,4- tetrazolium]-bis(4-methoxy-6-nitro) benzene sulfonic acid hydrate (xtt). the mtt and xtt colorimetric bacteric ... | 1993 | 8423367 |
| b cell tolerance induction by cross-linking of membrane igm, but not igd, and synergy by cross-linking of both isotypes. | previous studies in our laboratory demonstrated that overnight exposure of adult splenic b cells to anti-ig resulted in an unresponsive state characterized by decreased antibody synthesis but normal mitogen-driven proliferation (i.e., energy). because both anti-f(ab')2 and anti-mu were equally effective at inducing tolerance, it was important to determine whether cross-linking of igd together with or separately from igm influenced the induction of unresponsiveness. although anti-mu induced signi ... | 1993 | 8436810 |
| brucellosis in free-ranging bison (bison bison) from teton county, wyoming. | brucellosis was studied opportunistically in bison (bison bison) in the free-ranging jackson herd of approximately 120 in teton county, wyoming (usa) in march 1989. recent abortion was diagnosed in a 2-yr-old cow and brucella abortus biovar 1 was isolated from vaginal discharge, uterine contents, uterus, and supramammary lymph nodes. endometritis was characterized by lymphoplasmacytic infiltrates in the lamina propria and neutrophils in uterine glands and within necrotic debris and exudate in th ... | 1993 | 8445770 |
| comparison of brucella abortus antigen preparations for in vitro stimulation of immune bovine t-lymphocyte cell lines. | three brucella abortus antigen preparations were tested for stimulatory activity with immune bovine t-lymphocyte cell lines in vitro. a total of 32 polyclonal t-lymphocyte cell lines were derived from two steers each from four immunization groups: (1) b. abortus strain 19 (s19) alone, (2) heat-killed b. abortus whole bacterial cells (hkc) alone, (3) s19 with recombinant human interleukin 2 (rhuil-2), (4) hkc with rhuil-2. peripheral blood mononuclear cells were isolated at 2 and 9 weeks post imm ... | 1993 | 8447086 |
| cloning of genes for proline and leucine biosynthesis from brucella abortus by functional complementation in escherichia coli. | by selecting for growth of escherichia coli mutant strains in the absence of the required amino acid, clones were found in a brucella abortus library carrying genes for glutamyl phosphate reductase (proa) and beta-isopropylmalate dehydrogenase (leub). these clones hybridized to unique fragments in a genomic digest of b. abortus dna. the proa-complementing dna was found in a region of 1.3 kb, which directed the synthesis of a protein of 48,000 da with a pi of 6.3 in maxicells. the leub-complement ... | 1993 | 8450311 |
| placental pathology of the pregnant mouse inoculated with brucella abortus strain 2308. | fifty-five pregnant balb/c mice received various doses of brucella abortus virulent strain 2308 intraperitoneally on day 9 of gestation, and uteri and spleens were examined at 3, 5, 7, and 9 days post-inoculation to study the pathogenesis of infection. a dose of 10(5.7) b. abortus organisms produced a severe, necrosuppurative placentitis. bacteria multiplied preferentially within the placenta and were identified within the rough endoplasmic reticulum of trophoblast giant cells and within the vis ... | 1993 | 8470334 |
| lipopolysaccharide from brucella abortus behaves as a t-cell-independent type 1 carrier in murine antigen-specific antibody responses. | in order to determine the carrier nature of lipopolysaccharide from brucella abortus (lps-ba) in evoking humoral responses, normal and immunodeficient mice were immunized with trinitrophenyl (tnp)-conjugated lps-ba (tnp-lps-ba) and the responses were compared with those to known t-dependent and t-independent antigens. tnp-lps-ba, like t-independent type 1 (ti-1) antigens such as tnp-ba and tnp-lps from escherichia coli (tnp-lps-ec), generated anti-tnp responses in balb/c, athymic balb/c nu/nu, a ... | 1993 | 8478060 |
| iron augments macrophage-mediated killing of brucella abortus alone and in conjunction with interferon-gamma. | brucella abortus are gram negative facultative intracellular bacteria, which survive and replicate in host macrophages. we have recently demonstrated that activation of macrophages with interferon-gamma increases their anti-brucella activities but does not result in elimination of intracellular brucellae. here we demonstrate that iron-loaded macrophages have an enhanced capacity to kill or prevent replication of intracellular brucellae. iron added bound to transferrin or as a salt, iron-nitrilot ... | 1993 | 8495498 |
| modulation of the intracellular survival of brucella abortus by tuftsin and muramyl dipeptide. | tuftsin, a physiologic bioactive peptide of animal origin, and muramyl dipeptide, a synthetic bioactive glycopeptide of microbial origin, are known to enhance several recognized macrophage functions and increase non-specific resistance of the host against a number of pathogens. the influence of these two bioactive peptides was studied in permissive bovine mammary macrophages that were unable to control the intracellular replication of brucella abortus and restrictive bovine mammary macrophages t ... | 1993 | 8506616 |
| cytokine response of t-cell subsets from brucella abortus-infected mice to soluble brucella proteins. | hot saline extracts of brucella abortus 19 were separated by successive differential precipitation with 50 and 70% ammonium sulfate, yielding fractions sbp50, with predominantly 36-kda proteins and a number of medium-sized proteins (26 to 33 kda), and sbp70, with 14-kda and lower-molecular-mass proteins. both fractions stimulated specifically proliferation and cytokine production by spleen cells from brucella-infected mice, although the activity of sbp50 was much higher than that of sbp70. furth ... | 1993 | 8514387 |
| comparative performance of the enzyme-linked immunosorbent assay (elisa) and conventional assays in the diagnosis of bovine brucellosis in argentina. | the fao/iaea enzyme-linked immunosorbent assay (elisa) kit for the diagnosis of bovine brucellosis was compared in argentina with two screening tests, the rose bengal (rb) and the buffered plate antigen (bpa) agglutination tests and with two confirmatory tests, the 2-mercaptoethanol (2-me) agglutination and the complement fixation (cf) tests. in the testing of brucella abortus strain 19 (s19) vaccinated cattle from brucella-free dairy herds, the diagnostic specificity estimate of the elisa (99.7 ... | 1995 | 8533303 |
| effect of brucella abortus transfer factor in preventing murine brucellosis. | mice vaccinated with a protein extract of attenuated brucella abortus strain 19 had increased resistance to infection with virulent b. abortus strain 2308 and had increased antibody responses to strain 2308. however, resistance to infection and antibody responses were not increased when nonvaccinated recipient mice were given transfer factor preparations that were obtained from either vaccinated donor mice or strain 2308-infected donor mice. vaccination of mice with the strain 19 extract plus tr ... | 1995 | 8541805 |
| variation of brucella abortus 2308 infection in balb/c mice induced by prior vaccination with salt-extractable periplasmic proteins from brucella abortus 19. | the study compared the immune and protective responses induced in balb/c mice vaccinated with six salt-extractable periplasmic protein fractions (brucella cell surface proteins [bcsp]) of brucella abortus 19 and later challenge exposed with b. abortus 2308. bcsp70 was precipitated with ammonium sulfate at 70% saturation, and bcsp100 was precipitated with ammonium sulfate at 100% saturation by use of supernatant fluid of bcsp70 that had been precipitated with 70% ammonium sulfate. four subfractio ... | 1996 | 8550206 |
| cattle serologically positive for brucella abortus have antibodies to b. abortus cu-zn superoxide dismutase. | in this study, we demonstrated by a cu-zn superoxide dismutase-specific enzyme-linked immunoassay that cattle that are serologically positive for brucella abortus have serum immunoglobulin g antibodies to b. abortus cu-zn superoxide dismutase. the specificity of the antibody reactivity was confirmed by western blot (immunoblot) analysis with b. abortus salt-extractable proteins containing native cu-zn superoxide dismutase and with recombinant b. abortus cu-zn superoxide dismutase. the results re ... | 1994 | 8556493 |
| molecular characterization, occurrence, and immunogenicity in infected sheep and cattle of two minor outer membrane proteins of brucella abortus. | screening of a brucella abortus genomic library with two sets of monoclonal antibodies allowed the isolation of the genes corresponding to two minor outer membrane proteins (omp10 and omp19) found in this bacterial species. sequence analysis of the omp10 gene revealed an open reading frame capable of encoding a protein of 126 amino acids. the nucleotide sequence of the insert producing the omp19 protein contains two overlapping open reading frames, the largest of which (177 codons) was shown to ... | 1996 | 8557326 |
| sheep red blood cell and brucella abortus antibody responses in chickens selected for multitrait immunocompetence. | chickens from replicated lines divergently selected for multitrait immunocompetence were tested for their antibody responses to sheep red blood cells and brucella abortus antigen. all birds were injected with sheep red blood cells and b. abortus antigens at 4 and 9 wk of age, and blood samples were taken 6, 8, and 10 d postimmunization. antibody titers were determined by using agglutination assays. for sheep red blood cell responses, the most marked difference was between the high and low lines ... | 1995 | 8559724 |
| characterization of brucella abortus and brucella melitensis native haptens as outer membrane o-type polysaccharides independent from the smooth lipopolysaccharide. | brucella native haptens (nhs) extracted with hot water from smooth (s)-type b. abortus and b. melitensis were purified to high levels of serological activity and compared with the polysaccharide obtained by acid hydrolysis (ps) of the s lipopolysaccharide (s-lps). by 13c nuclear magnetic resonance analysis, nhs showed the spectrum of a homopolymer of alpha-1,2- or alpha-1,2- plus alpha-1,3-linked 4-formamido-4,6-dideoxy-d-mannose (n-formylperosamine) previously reported for the lps o chain. howe ... | 1996 | 8576040 |
| heterogeneity of brucella abortus lipopolysaccharides. | this work demonstrates that brucella lipopolysaccharide (lps) preparations are a family of related molecules which display heterogeneity not only at the level of the o polysaccharide, but also at the core oligosaccharide and the lipid a. sodium dodecyl sulphate/polyacrylamide gel electrophoresis and western blotting showed that lps from brucella strains displayed molecular weight and antigenic heterogeneity. smooth-type lps (s-lps) from b. abortus demonstrated three broad high-molecular-weight b ... | 1995 | 8577998 |
| the reca protein as a model molecule for molecular systematic studies of bacteria: comparison of trees of recas and 16s rrnas from the same species. | the evolution of the reca protein was analyzed using molecular phylogenetic techniques. phylogenetic trees of all currently available complete reca proteins were inferred using multiple maximum parsimony and distance matrix methods. comparison and analysis of the trees reveal that the inferred relationships among these proteins are highly robust. the reca trees show consistent subdivisions corresponding to many of the major bacterial groups found in trees of other molecules including the alpha, ... | 1995 | 8587109 |
| rates of seroconversion in the progeny of brucella abortus seropositive and seronegative cattle and buffalo. | the authors estimated the rates of development of serum antibodies against brucella abortus, between january 1987 and december 1990, in female jersey cattle and buffalo weaned from seropositive and seronegative dams, and used logistic regression analysis to examine the epidemiological relationship of these rates with the serum antibody status of dams. the offspring from both seropositive and seronegative dams were reared together in calf pens, while separate pens were used for bovine and buffalo ... | 1995 | 8593403 |
| serum sensitivity of field isolates and laboratory strains of brucella abortus. | to evaluate the ability of bovine complement to kill a variety of field isolates and laboratory strains of brucella abortus. | 1995 | 8599519 |
| detection of brucella abortus antigens by immunoperoxidase histochemical staining of lochia smears. | an immunoperoxidase histochemical staining technique for the detection of brucella abortus organisms in lochia of brucellosis-infected cows was described. in comparison with the standard culture technique, the former method resulted in 36% false positive and 2.3% false negative reactions, which represents a sensitivity of 82% and a specificity of 94%. false positive reactions are presumably the result of organisms which succumbed during transit. the feasibility of the test in the confirmation of ... | 1995 | 8600440 |
| brucella abortus conjugated with a peptide derived from the v3 loop of human immunodeficiency virus (hiv) type 1 induces hiv-specific cytotoxic t-cell responses in normal and in cd4+ cell-depleted balb/c mice. | we have previously shown that immunization of mice with human immunodeficiency virus (hiv)-derived proteins or peptides conjugated to inactivated brucella abortus induces the secretion of virus-neutralizing antibodies, predominantly of the immunoglobulin g2a (igg2a) isotype. in addition, b. abortus activates human cd4+ and cd8+ cells to secrete gamma interferon. since these are both characteristics of a th1-type immune response, which is associated with the development of cell-mediated immunity, ... | 1996 | 8627787 |
| experimental studies on brucella abortus in moose (alces alces). | four moose (alces alces) were inoculated conjunctivally with b. abortus biovar 1 to determine their susceptibility to brucellosis, and to describe the serology, bacteriology, hematology, clinical chemistry, and pathology associated with infection. all moose became infected. two moose were killed at day 70 post-exposure, one (83f) died acutely at day 85, and one was killed at day 166. none of the moose had clinical signs, except for 83f immediately before death. infected moose were readily detect ... | 1996 | 8627944 |
| direct detection of brucella spp. in raw milk by pcr and reverse hybridization with 16s-23s rrna spacer probes. | the 16s-23s rrna spacer regions of brucella abortus, b. melitensis, and b. suis were cloned and subcloned after pcr amplification. sequence analysis of the inserts revealed a spacer of about 800 bp with very high ( > 99%) homology among the three species examined. two genus-specific primer pairs, bru-p5-bru-p8 and bru-p6-bru-p7, that could be used in a nested pcr format and three genus-specific dna probes, bru-icg2, bru-icg3, and bru-icg4, were deduced from this spacer. the specificity and sensi ... | 1996 | 8633866 |
| lymphocyte proliferation in response to brucella abortus rb51 and 2308 proteins in rb51-vaccinated or 2308-infected cattle. | cattle vaccinated with brucella abortus strain rb51 (srb51) or infected with strain 2308 (s2308) had lymph node lymphocytes which proliferated most when incubated with 32-, 27-, 18-, or <18-kda proteins of either srb51 or s2308. some s2308-infected cattle but no srb51-vaccinated cattle had lymphocytes which proliferated in response to 80- and 49-kda proteins of srb51 and s2308. these results suggest that cattle vaccinated with srb51 or infected with s2308 have lymphocytes which proliferate in re ... | 1996 | 8641749 |
| antibody responses to brucella abortus 2308 in cattle vaccinated with b. abortus rb51. | cattle vaccinated with brucella abortus rough strain rb51 (srb51) produced small amounts of serum immunoglobulin g (igg) but no igm antibody to smooth strain 2308 (s2308) bacteria and produced no igg or igm antibody to s2308 lipopolysaccharide (lps). western immunoblot analysis revealed that antiserum from srb51-vaccinated cattle contained igg antibody that reacted with s2308 proteins of 84 to <20 kda. however, antiserum from the vaccinated cattle did not contain agglutinating b. abortus antibod ... | 1996 | 8641754 |
| residual anti-brucella abortus strain 19 antibodies detected in adult cattle by two indirect-elisa tests. | | 1996 | 8650919 |
| brucella abortus differs in the multiplication within bovine chorioallantoic membrane explants from early and late gestation. | the ability of brucella to infect and grow within extraplacentomal chorioallantoic explants (cams) derived from early and late gestational cattle was compared. following inoculation of cams with equal numbers of strain 2308 b. abortus, the infectivity was approximately the same in cams from both ages, however, bacterial replication was significantly greater in late gestational cams than in early gestational cams. co-culture of both early and late gestation cams or culture of both types of cams i ... | 1996 | 8654046 |
| identification of a rhodococcus gene cluster encoding a homolog of the 17-kda antigen of brucella and a putative regulatory protein of the asnc-lrp family. | by sequence analysis, a gene encoding a homolog of the 17-kda protein antigen of the gram-negative pathogen brucella abortus (hemmen et al., clin diagn lab immunol 2: 263, 1995) was identified in the nocardioform actinomycete rhodococcus sp. ni86/21. database searching also revealed a partial human cdna sequence for a putative eukaryotic homolog of this presumptive brucella-specific protein. these proteins display a low but significant level of similarity with lumazine synthases involved in bact ... | 1996 | 8661681 |
| humoral immune responses against particulate bacterial antigens are dependent on marginal metallophilic macrophages in the spleen. | lymphoid organs are populated by different macrophage subpopulations. in the spleen, four subpopulations can be characterized using differences in, for example, morphology, localization, cell markers and repopulation kinetics after liposome-mediated depletion. the involvement of the different macrophage subpopulations in the immune response to particulate antigens was studied in vivo by intravenous injection of clodronate containing liposomes to eliminate the splenic macrophages, followed by imm ... | 1996 | 8668919 |
| nucleotide sequence and expression of the gene encoding the major 25-kilodalton outer membrane protein of brucella ovis: evidence for antigenic shift, compared with other brucella species, due to a deletion in the gene. | the nucleotide sequences encoding the major 25-kda outer membrane protein (omp) (omp25 genes) of brucella ovis 63/290, brucella melitensis 16m, brucella suis 1330, brucella canis rm6/66, and brucella neotomae 5k33 (all reference strains) were determined and compared with that of brucella abortus 544 (p. de wergifosse, p. lintermans, j. n. limet, and a. cloeckaert, j. bacteriol. 177:1911-1914, 1995). the major difference found was between the omp25 gene of b. ovis and those of the other brucella ... | 1996 | 8675306 |
| cloning of a brucella melitensis group 3 antigen gene encoding omp28, a protein recognized by the humoral immune response during human brucellosis. | brucella group 3 antigens (ags) are outer membrane proteins (omps) with a molecular mass ranging from 25 to 30 kda. the omps are of interest partially because of their potential use as vaccine and diagnostic reagents. we used human convalescent antibody (ab) to clone a gene that encoded a 28-kda protein from a lambdagt11 library of brucella melitensis 16m genomic dna. dna sequence analysis revealed a single open reading frame that would encode a protein of 26,552 da. the 28-kda protein had a pri ... | 1996 | 8698471 |
| tumor necrosis factor alpha and interleukin-12 contribute to resistance to the intracellular bacterium brucella abortus by different mechanisms. | both interleukin-12 (il-12) and tumor necrosis factor alpha (tnf-alpha) are produced early in intracellular bacterial infection. depletion of either il-12 or tnf-alpha by a single injection of specific antibody 4 h before the injection of brucella abortus 19 led to the exacerbation of infection 2 weeks later. whereas the effect of il-12 depletion on resistance was persistent and exacerbation was still significant 6 weeks later, the bacterial numbers in mice depleted of tnf-alpha were similar to ... | 1996 | 8698508 |
| infection of cattle with yersinia enterocolitica o:9 a cause of the false positive serological reactions in bovine brucellosis diagnostic tests. | during the last four years, an increasing number of cattle herds were classified positive by brucellosis screening tests in areas of belgium and france free of the disease. no clinical symptom of brucellosis was reported in these animals and no brucella abortus strains were isolated. after two years, no brucellosis outbreak was registered in all of the herds concerned. on this basis, all the serological reactions observed were classified as false positive. an elisa using yersinia outer membrane ... | 1996 | 8701566 |
| serological response of cattle to brucella allergen after repeated intradermal applications of this allergen. | a study was conducted to determine whether an allergen that has been prepared from a mucoid strain of brucella abortus triggers a serum antibody response that interferes with the interpretation of serologic tests results. fifteen cattle seronegative for brucella antigen were tested with the sdth test several times. blood samples were collected weekly and tested with the serum agglutination test and complement fixation test. results show that some cattle tested seronegative after each of the sdth ... | 1996 | 8701573 |
| a comparison of the potency of several brucella allergens used to detect brucellosis in cattle. | the potency of brucella allergens prepared from a smooth brucella abortus strain s-99, mucoid strain leewarden, rough strain 45/20, and rough brucella melitensis strain b-115 was assessed. the potency of these allergens was compared with that of a standard allergen prepared from smooth brucella abortus s-99 that efficiently detected bovine brucellosis in other studies. eight cattle experimentally inoculated with brucella abortus 544 were tested with the allergens 4 and 10 weeks after infection, ... | 1996 | 8711894 |
| polymorphism in brucella strains detected by studying distribution of two short repetitive dna elements. | thirty-four brucella reference or field strains representing all the species and biovars were studied by repetitive element sequence-based pcr, a pcr using primers complementary to two enterobacterial short repetitive sequences: repetitive extragenic palindromic and enterobacterial repetitive intergenic consensus sequences. all the stains showed a positive amplification, suggesting that the brucella genome contains such sequences. repetitive extragenic palindromic pcr was less discriminating tha ... | 1996 | 8727925 |
| in vitro and in vivo phenotypes resulting from deletion of the high temperature requirement a (htra) gene from the bovine vaccine strain brucella abortus s19. | an htra deletion mutant was created in the bovine vaccine strain, b. abortus s19, by replacing the majority of the htra gene with a kanamycin resistance gene. antibiotic selection for a double crossover event yielded kanamycin-resistant, ampicillin-sensitive colonies confirmed by southern and western blot analysis to be htra deficient. the b. abortus s19 htra mutant was significantly more susceptible than the parental strain to killing by h2o2 (p < 0.001) and o(2)- generated by the redox cycling ... | 1996 | 8734637 |
| an unusual case of brucellosis in japan: difficulties in the differential diagnosis from pulmonary tuberculosis. | human brucellosis is an imported zoonosis extremely uncommon in japan. brucellosis was found in a 38-year-old surgeon who had never been abroad; he developed intrapulmonary infiltrates and pleural thickening indistinguishable from pulmonary tuberculosis. despite extensive antibiotic therapy for tuberculosis he developed systemic serositis. a culture of resected lung tissues grew co2-required coccobacilli. polymerase chain reaction test using a specific primer pair for brucella abortus revealed t ... | 1996 | 8739788 |
| morphometric and histopathologic analysis of lymphoid depletion in murine spleens following infection with brucella abortus strains 2308 or rb51 or an htra deletion mutant. | balb/c mice were inoculated intraperitoneally with suspensions of brucella abortus strains 2308 or rb51 or an htra mutant. spleens were examined on postinoculation day (pid) 2, 4, 7, 10, 15, 21, 30, and 60. brucellae were cultured in high numbers from the spleens of mice infected with strains 2308 or htra through pid 60; however, mice infected with strain rb51 cleared the infection between pid 30 and pid 60. histopathologic changes in spleens from 2308-infected mice were characterized by marked ... | 1996 | 8740701 |
| improvement of the brucella abortus b19 vaccine by its preparation in a glycerol based medium. | the brucella abortus b19 vaccine strain differs from other brucella strains in its sensitivity to erythritol. however, erythritol tolerant (eri(t)) mutants arise from sensitive cultures of b19 at high rate, and may cause persistence and/or abortion when the vaccine is inoculated on adult cattle. twelve different batches of b19 have been examined for the presence of eri(t) mutants. all contained eri(t) variants at a proportion ranging from 10(-4) to 10(-6). in order to eliminate these mutants fro ... | 1996 | 8744552 |
| behaviour of a high-temperature-requirement a (htra) deletion mutant of brucella abortus in goats. | previous studies have shown that high-temperature-requirement a (htra) mutants of brucella abortus are more sensitive to oxidative killing in vitro, are less able to survive in cultured murine macrophages and are attenuated in balb/c mice. to measure the effect of an htra mutation on the virulence of b abortus in ruminants, pregnant goats in late gestation were exposed to infection by the conjunctival route with b abortus 2308 or an isogenic htra mutant, phe1. infection with either 2308 or phe1 ... | 1996 | 8745255 |
| morphometric analysis of cd4+, cd8+, and gamma/delta+ t-lymphocytes in lymph nodes of cattle vaccinated with brucella abortus strains rb51 and 19. | t-lymphocyte subpopulations were examined in vivo by computer-assisted morphometry of superficial cervical lymph nodes of cattle vaccinated with brucella abortus. twenty-four 8-month-old hereford heifers were injected subcutaneously in the axillary area with 1 x 10(10) live b. abortus strain rb51 (srb51, n = 12) or strain 19 (s19, n = 6) suspended in 2 ml of saline. six control heifers were injected with sterile saline. lymph nodes were collected at 1, 2, 4, 6, 10 and 12 weeks postvaccination. b ... | 1995 | 8746701 |
| cloning of brucella abortus gene and characterization of expressed 26-kilodalton periplasmic protein: potential use for diagnosis. | brucella spp. are the causative agents of brucellosis in many different hosts, including humans. most of the serological methods of diagnosis are based on the detection of antilipopolysaccharide antibodies, which makes the differentiation of vaccinated animals from infected animals difficult. by using molecular biology techniques, a gene that encodes a 26-kda protein (bp26) was isolated from a brucella abortus s19 genome lambda gt11 library. this protein is in the periplasm of b. abortus and in ... | 1996 | 8748294 |
| serological crossreactivity between brucella abortus and yersinia enterocolitica 0:9 i immunoblot analysis of the antibody response to brucella protein antigens in bovine brucellosis. | sera from three groups of brucella abortus infected cattle were examined in immunoblots with the following antigens: sodium dodecyl sulfate/mercapto ethanol (sds/me) extracts of two rought b. abortus strains (45/20 and rb51) and rough b. ovis, smooth lipopolysaccharides (slps) from b. abortus strain 99 and y. enterocolitica 0:9, and a cytoplasmic extract from smooth b. abortus strain 19-s. the sera groups were: (1) 26 sera from animals, experimentally infected with b. abortus strain 544, which w ... | 1995 | 8748541 |
| serological crossreactivity between brucella abortus and yersinia enterocolitica 0:9 ii the use of yersinia outer proteins for the specific detection of yersinia enterocolitica infections in ruminants. | yersinia outer protein (yop) preparations from y. enterocolitica and y. pseudotuberculosis were used as antigens in immunoblots for the detection of yersinia infections in experimentally and naturally infected ruminants. sera from 9 groups of animals were used: (1) 51 sera from cattle which were false-positive in the standard brucellosis serological tests, (2) 52 sera from brucellosis-negative cattle, (3) 51 sera from a deer herd in which 16 animals were positive in the brucellosis tests and yer ... | 1995 | 8748542 |
| brucella abortus as a potential vaccine candidate: induction of interleukin-12 secretion and enhanced b7.1 and b7.2 and intercellular adhesion molecule 1 surface expression in elutriated human monocytes stimulated by heat-inactivated b. abortus. | development of a vaccine which is capable of generating a strong cellular immune response associated with gamma interferon (ifn-gamma) production and cytotoxic t-cell development requires that the immunogen be capable of inducing the secretion of interleukin-12 (il-12), which is a pivotal factor for the differentiation of th1 or tc1 cells. we have previously shown that the heat-inactivated gram-negative bacterium brucella abortus can induce ifn-gamma secretion by t cells. in the present study, w ... | 1996 | 8757841 |
| purification and antigenic analysis of the major 25-kilodalton outer membrane protein of brucella abortus. | the major 25-kda outer membrane protein (omp25) of brucella abortus was purified and antigenically characterized by use of monoclonal antibodies (mabs). purification was achieved from the sodium dodecyl sulphate-insoluble (sds-i) cell wall (cw) fraction of vaccine strain b. abortus b19 which was shown by use of mabs to contain the two major outer membrane proteins of 25 and 36 kda linked to peptidoglycan, smooth lipopolysaccharide (s-lps), and rough lps (r-lps). purity of omp25 was checked with ... | 1996 | 8763610 |
| cloning, nucleotide sequence, and expression of the brucella melitensis bp26 gene coding for a protein immunogenic in infected sheep. | we have previously identified a brucella melitensis 28 kda cytosoluble protein (cp28) which was highly immunogenic in infected sheep and which in addition made possible the serological differentiation between infected and b. melitensis rev. 1 vaccinated sheep. monoclonal antibodies against cp28 were used to screen a b. melitensis 16m genomic library and to clone the corresponding gene. dna sequencing of the gene encoding cp28 of b. melitensis 16m revealed that it was nearly identical to that of ... | 1996 | 8764475 |
| effect of composition and method of preparation of liposomes on their stability and interaction with murine monocytes infected with brucella abortus. | the success of the use of liposomes as drug carriers depends on both their formulation and the method of preparation. we have carried out a series of in vitro studies using different formulations and preparation methods, with the aim of obtaining a type of liposome which is efficient in the treatment of brucellosis. on the basis of results obtained in studies of stability at 37 degrees c in the presence of serum lipoproteins and of the activation of phagocytic cells and antibiotic transport to t ... | 1996 | 8787896 |
| effect of antibiotics contained in two brucella selective media on growth of brucella abortus, b. melitensis, and b. ovis. | the mic and the highest concentration enabling bacterial growth (ceg) of the antibiotics contained in two selective media were determined for brucella abortus, b. melitensis, and b. ovis. the nalidixic acid and bacitracin contained in farrell's selective medium were responsible for the inhibitory effects observed. | 1996 | 8789029 |
| rapid laboratory confirmation of human brucellosis by pcr analysis of a target sequence on the 31-kilodalton brucella antigen dna. | we developed a pcr-based assay for the rapid and specific laboratory diagnosis of human brucellosis directly from whole blood. specimens were collected in edta tubes from 17 patients with acute serologic brucellosis and 3 patients with chronic relapsing brucellosis as determined by serologic tests and the patient's clinical picture. dna was extracted from peripheral mononuclear cells obtained from the blood of patients with brucellosis and control individuals. specific primers for the pcr amplif ... | 1996 | 8789045 |
| humoral immune response against lipopolysaccharide and cytoplasmic proteins of brucella abortus in cattle vaccinated with b. abortus s19 or experimentally infected with yersinia enterocolitica serotype 0:9. | the humoral immune responses against three different antigens of brucella abortus were monitored by enzyme-linked immunosorbent assay in cattle vaccinated with b. abortus s19 or experimentally infected with yersinia enterocolitica serotype 0:9. immunoglobulin g (igg) and igm responses against (i) b. abortus lipopolysaccharide (lps), (ii) total cytoplasmic proteins depleted of lps (lps-free cyt), and (iii) b. abortus 18-kda cytoplasmic protein were measured. vaccinated animals and yersinia-infect ... | 1996 | 8807216 |
| infection of cattle with brucella abortus biovar 1 isolated from a bison in wood buffalo national park. | an experiment was conducted to determine if cattle could be infected with a strain of brucella abortus biovar 1 isolated from a bison in wood buffalo national park. three pregnant cows inoculated conjunctivally with 5.7 x 10(8) cfu of the bacterium, and their subsequent calves, showed seroconversion on standard serological tests for bovine brucellosis, and large numbers of the bacterium were isolated from numerous tissues at necropsy. a 4th cow that was moved into the pen that previously contain ... | 1996 | 8809394 |
| a homogeneous fluorescence polarization assay for detection of antibody to brucella abortus. | a homogeneous fluorescence polarization (fp) assay (fpa) was developed for detection of antibody in bovine sera to brucella abortus. the assay used o-polysaccharide prepared from b. abortus lipopolysaccharide in the molecular weight range of 20-30 kda which was conjugated with fluorescein isothiocyanate and used as a tracer. fluorescence polarization was measured with a fpm-1 fluorescence polarization analyzer. sample (20 microliters) was added to 2.0 ml of diluent buffer at ambient temperature. ... | 1996 | 8814332 |
| mastitis in camelus dromedarius and the somatic cell content of camels' milk. | seven hundred and sixty-three camels from 400 herds of local sudanese camel breeds were investigated for the prevalence of mastitis, identification of its bacterial causes and determination of the leucocyte contents of camel's milk. one hundred and forty-nine (19.5 per cent) of the 763 camels examined were diagnosed as mastitis cases based on clinical signs. one hundred and fifty-nine (47.3 per cent) of the 336 randomly selected milk samples were reactive in a rapid mastitis test and 16 of the 1 ... | 1996 | 8819195 |
| the sensitizing effect of a brucella abortus antigen in cattle after repeated intradermal inoculations. | an antigen prepared from a mucoid strain of b. abortus was repeatedly injected intradermally into cattle to determine whether it sensitizes cattle so that they test false positive with the skin delayed-type hypersensitivity (sdth) test. cattle (n = 14) that were experimentally inoculated. with microorganisms that serologically cross-react with b. abortus, and uninfected cattle (n = 15) were tested with the antigen 2 to 5 times over a period of 16 to 17 weeks. an increase in skinfold thickness of ... | 1996 | 8828125 |
| the effects of magainin 2, cecropin, mastoparan and melittin on brucella abortus. | the effect of the alpha-helical polycationic peptides magainin 2, melittin, mastoparan and cecropin on the viability of brucella abortus 544 (type species), b. abortus s19 (vaccine strain) and b. abortus s2308 (vaccine challenge strain) was determined. rough mutants of these strains and the rough candidate vaccine strain b. abortus rb51 were also tested. s. typhimurium was used as a control. the peptides did not affect the viability of b. abortus smooth strains but some of the peptides affected ... | 1996 | 8828135 |
| brucella-salmonella lipopolysaccharide chimeras are less permeable to hydrophobic probes and more sensitive to cationic peptides and edta than are their native brucella sp. counterparts. | a rough (r) brucella abortus 45/20 mutant was more sensitive to the bactericidal activity of polymyxin b and lactoferricin b than was its smooth (s) counterpart but considerably more resistant than salmonella montevideo. the outer membrane (om) and isolated lipopolysaccharide (lps) of s. montevideo showed a higher affinity for these cationic peptides than did the corresponding b. abortus om and lps. we took advantage of the moderate sensitivity of r b. abortus to cationic peptides to construct l ... | 1996 | 8830680 |
| differential antibody responses in 6.b major histocompatibility (b) complex congenic chickens. | lines 6.6-2 (b2b2) and 6.15-5 (b2b2), congenic for the major histocompatibility (b) complex with > 99.9% background gene uniformity, were used to examine primary antibody responses to two antigens. in each of two trials, 1 ml of 5% srbc, a t cell-dependent antigen, or 0.1 ml of brucella abortus (ba), a t cell-independent antigen, was injected into separate groups of each b genotype aged 3 and 6 wk. blood samples were taken from the chickens 7 d after immunization. serum titers (log2) for both to ... | 1996 | 8833372 |
| effects of age at vaccination on efficacy of brucella abortus strain rb51 to protect cattle against brucellosis. | to establish that female calves vaccinated with brucella abortus strain rb51 at 3, 5, and 7 months of age are protected against infection and abortion when challenged exposed during their first pregnancy. | 1996 | 8836366 |
| specific, nonradioactive detection of the nhp bacterium in penaeus vannamei by in situ hybridization. | necrotizing hepatopancreatitis (nhp) is a disease of farm-raised pacific white shrimp (penaeus vannamei) caused by a pleomorphic intracellular bacterium. a dna probe that is specific for the etiologic agent of necrotizing hepatopancreatitis was devised and tested in an in situ hybridization assay. a procedure was developed for labeling a single-stranded dna probe with digoxigenin by the polymerase chain reaction. the dna probe encompasses the v1 and v2 variable regions of the 16s ribosomal rna ( ... | 1996 | 8844575 |
| contradictory roles for antibody and complement in the interaction of brucella abortus with its host. | the ability of serum complement to kill bacteria has been linked to host resistance to gram-negative bacteria. a mechanism for killing extracellular organisms during early invasion, following release from infected phagocytic cells, or during bacteremia would contribute to a host's ability to resist disease. in fact, the ability of serum complement to kill bacteria has been linked to disease resistance. brucella abortus are gram-negative intracellular pathogens. resistance to these bacteria invol ... | 1995 | 8845060 |
| identification of sodc encoding periplasmic [cu,zn]-superoxide dismutase in salmonella. | sodc, encoding [cu,zn]-cofactored superoxide dismutase, once thought to be virtually confined to eukaryotes, has now been described in many gram-negative pathogens that have their primary niche of colonization in the upper respiratory tract. their role in host-parasite interactive biology is unknown. we here show that members of the major human and animal enteric pathogenic species salmonella harbour a version of sodc most closely resembling that found in brucella abortus. the enzyme it encodes ... | 1996 | 8869506 |
| immunization of mice with recombinant l7/l12 ribosomal protein confers protection against brucella abortus infection. | balb/c mice were immunized with the recombinant brucella abortus l7/l12 ribosomal protein fused to maltose binding protein (mbp). vaccinated animals mounted a specific immune response to the recombinant fusion protein as demonstrated by immunoblot analyses. additionally, b. abortus l7/l12 ribosomal protein conferred a significant degree of protection when compared to mice vaccinated with adjuvant alone, adjuvant plus mbp or b. abortus. these results indicate that a recombinant b. abortus protein ... | 1996 | 8873388 |
| endogenous gamma interferon and interleukin-10 in brucella abortus 2308 infection in mice. | cd-1 mice intravenously infected with the virulent brucella abortus 2308 strain simultaneously produce significant levels of gamma interferon (ifn-gamma) and interleukin-10 (il-10) in their spleens between the second and eighth day post-infection with no production of interleukin-4 (il-4). endogenous synthesis of il-10 does not affect the production of ifn-gamma in this organ, while the production of both cytokines during this period of time is accompanied by a statistically significant increase ... | 1996 | 8880135 |
| seroprevalences of brucellosis, q-fever and toxoplasmosis in slaughter livestock in trinidad. | serum samples obtained from livestock (cattle, chickens, pigs, sheep, goats and water buffaloes) slaughtered at various slaughter houses in trinidad were screened for agglutinins to three zoonosis causing pathogens. of a total of 751 sera tested, 2 (0.3%) originating from chickens were positive for brucella abortus agglutinins using the rose bengal test (rbt), but both were negative by the tube serum agglutination test (sat). thirty-six (4.8%) of 749 sera were positive for coxiella burnetii aggl ... | 1996 | 8881416 |
| immune responses and resistance to brucellosis in mice vaccinated orally with brucella abortus rb51. | immune responses and resistance to infection with brucella abortus 2308 (s2308) were measured in mice following oral or intraperitoneal (i.p.) vaccination with strain rb51 (srb51). bacteria persisted in the parotid lymph node for 4 weeks following oral vaccination of mice with 5 x 10(8) or 5 x 10(6) cfu of srb51. bacteria did not appear in the spleen during 12 weeks after oral vaccination, whereas they did appear in the spleen for 8 weeks following i.p. vaccination of mice with srb51 (5 x 10(8) ... | 1996 | 8890203 |
| the htra stress response protease contributes to resistance of brucella abortus to killing by murine phagocytes. | compared with virulent brucella abortus 2308, the isogenic htra mutant phe1 shows decreased resistance to killing by cultured murine neutrophils and macrophages and significant attenuation during the early stages of infection in the balb/c mouse model. these findings further define the contributions of the htra gene product to the pathogenesis of b. abortus infections. | 1996 | 8890248 |
| changes in blood and spleen lymphocyte populations following antigen challenge in immature male chickens. | 1. the effects of antigen (ag) injection on the distribution of lymphocyte populations of cornell k-strain male chickens were studied. 2. two experiments were conducted. in the first, chickens were injected with brucella abortus (ba), a purported t-independent antigen. in the second, chickens were injected with sheep red blood cells (srbc), a t-dependent antigen. peripheral blood lymphocytes (pbl) and spleen lymphocytes isolated at 0, 3, 6, 9, 12 and 24 h following ag injection were stained with ... | 1996 | 8894226 |
| determination of stability of brucella abortus rb51 by use of genomic fingerprint, oxidative metabolism, and colonial morphology and differentiation of strain rb51 from b. abortus isolates from bison and elk. | brucella abortus rb51 and isolates from cattle, bison, and elk were characterized by pulsed-field gel electrophoresis and standard techniques for biotyping brucella species, which included biochemical, morphological, and antigenic techniques, phage susceptibility, and antibiotic resistance. the objectives were to ascertain the stability of rb51 and to differentiate rb51 from other brucellae. genomic restriction endonuclease patterns produced by pulsed-field gel electrophoresis demonstrated a uni ... | 1996 | 8904427 |
| prepatellar bursitis caused by brucella abortus. | | 1996 | 8913256 |
| development and validation of an indirect enzyme immunoassay for detection of antibody to brucella abortus in milk. | an indirect enzyme immunoassay for detection of antibody to brucella abortus in bovine milk was developed and validated using 6238 milk samples from canadian herds (brucellosis free) and 202 samples from herds infected with b. abortus (from argentina and chile). the assay utilized lipopolysaccharide as the antigen, immobilized on the polystyrene matrix, whole milk to test and a mouse monoclonal antibody, specific for an epitope of bovine igg1, conjugated with horseradish peroxidase. the sensitiv ... | 1996 | 8914260 |
| abortion and placentitis in pregnant bison (bison bison) induced by the vaccine candidate, brucella abortus strain rb51. | to determine the ability of brucella abortus strain rb51 to induce placentitis and abortion in bison after sc vaccination. | 1996 | 8915438 |
| cloning, expression and sequence analysis of the bartonella henselae gene encoding the htra stress-response protein. | a cloned fragment of bartonella (rochalimaea) henselae (bh) dna was found to direct synthesis of an immunoreactive protein in escherichia coli (ec). sequence analysis revealed an open reading frame of 1509 nucleotides encoding a protein of 503 amino acids that exhibited extensive identity (over the entire protein) with the htra stress-response proteins of brucella abortus (59%), ec (37%) and salmonella typhimurium (36%). when the putative htra gene was amplified by polymerase chain reaction and ... | 1996 | 8921888 |
| effect of chronic fenvalerate (synthetic pyrethroid) intoxication on the immune response of goats to brucella abortus strain 19 vaccine. | fenvalerate, a widely used pesticide, was administered orally to goats at a dose rate of 15 mg/kg body weight, daily for 270 days. after 90 days of dosing, the animals, together with appropriate controls, were vaccinated with brucella abortus strain 19. the fenvalerate reduced both the humoral and cell-mediated immune responses, as assessed by the standard tube agglutination test and delayed hypersensitivity test, respectively. | 1996 | 8923239 |
| immunological response to the brucella abortus groel homolog. | western blot (immunoblot) analysis of sera from cattle vaccinated with brucella abortus s19 exhibit an elevated serologic response to hsp62, the groel homolog (bagroel). serologic screening of individual cows vaccinated with b. abortus s19 revealed no correlation between the immune response to bagroel and protection against a challenge with virulent organisms. the humoral immune response to bagroel was restricted to a region of the mature protein which mapped to amino acids 317 to 355 and may re ... | 1996 | 8926120 |
| identification and comparison of macrophage-induced proteins and proteins induced under various stress conditions in brucella abortus. | brucella abortus is a facultative intracellular pathogen of cattle and humans that is capable of survival inside macrophages. in order to understand how b. abortus copes with the conditions during intracellular growth in macrophages, the protein synthesis pattern of the bacteria grown inside bovine macrophages has been compared with that of bacteria grown in the cell culture medium by two-dimensional polyacrylamide gel electrophoresis. approximately 24 new proteins that are not detected in the b ... | 1996 | 8945577 |
| experimental infection of pregnant cattle with the vaccine candidate brucella abortus strain rb51: pathologic, bacteriologic, and serologic findings. | to determine the placental tropism and abortigenicity of the vaccine candidate brucella abortus strain rb51 (srb51), a rough mutant of the virulent strain 2308, ten polled hereford heifers were inoculated intravenously in the 6th month of gestation. heifers were euthanatized and examined at postinoculation week (piw) 8 (n = 5) or at full term (n = 5). four of five infected heifers sampled at piw 8 and three of four infected heifers at term had placentitis, whereas reproductive tissues of three n ... | 1996 | 8952027 |
| serologic responses of brucella abortus strain 19 calfhood-vaccinated cattle following adult vaccination with strain rb51. | this study was designed to determine if brucella abortus strain rb51, which expresses small amounts of the lipopolysaccharide o side chain, would cause positive responses on brucellosis serologic surveillance tests when given to adult cattle that were vaccinated as calves with b. abortus strain 19. cattle vaccinated as adults with strain rb51 that had been vaccinated as calves with strain 19 (n = 40) had significantly greater antibody titers (p < 0.05) against strain rb51 at 4 and 8 weeks postva ... | 1996 | 8953530 |
| a possible mitochondrial gene in the early-branching amitochondriate protist trichomonas vaginalis. | trichomonads are anaerobic flagellated protists that, based on analyses of ribosomal rna sequences, represent one of the earliest branching lineages among the eukaryotes. the absence of mitochondria in these organisms coupled with their deep phylogenetic position has prompted several authors to suggest that trichomonads, along with other deeply-branching amitochondriate protist groups, diverged from the main eukaryotic lineage prior to the endosymbiotic origin of mitochondria. in this report we ... | 1996 | 8962102 |
| recombinant brucella abortus proteins that induce proliferation and gamma-interferon secretion by cd4+ t cells from brucella-vaccinated mice and delayed-type hypersensitivity in sensitized guinea pigs. | optimal protective immunity to brucella abortus infection is dependent on a coordinate interaction between different t-cell subsets which leads to an antigen-specific t-lymphocyte-mediated activation of macrophages, the main cellular reservoir for the bacterium. as an initial step in the identification of bacterial proteins that mediate cellular immunity, we have subcloned the b. abortus ssb, uvra, groes, and groel genes into the prokaryotic expression vector pmal-c2 using pcr. escherichia coli ... | 1996 | 8964089 |
| t lymphocyte mediated protection against facultative intracellular bacteria. | acquired immunity against intracellular bacteria is t cell dependent. t cells play a major role in protection against intracellular bacteria, but bacterial antigens recognized by t cells have been studied less extensively than bacterial antigens recognized by b cells. using t lymphocytes from animals immunized against brucella abortus, we have screened a bacterial genomic library for genes encoding antigens recognized by t cells. lymphocytes that proliferated to b. abortus proteins were characte ... | 1996 | 8988876 |
| binding of the brucella abortus lipopolysaccharide o-chain fragment to a monoclonal antibody. quantitative analysis by fluorescence quenching and polarization. | an antigenic o-chain polysaccharide fragment derived from brucella abortus lipopolysaccharide was labeled with 14.8 +/- 1.8 (n = 5) and 52.3 +/- 2.4 (n = 3) micromol of fluorescein/g of polysaccharide (designated fl1 and fl2, respectively) for use in investigating the binding of o-chain to a specific murine antibody yst9 under equilibrium conditions. upon binding to yst9, the fluorescence of fl1 and fl2 was quenched 45-57% with no shift in the excitation and emission spectra, and polarization of ... | 1997 | 9006923 |
| characterization, occurrence, and molecular cloning of a 39-kilodalton brucella abortus cytoplasmic protein immunodominant in cattle. | monoclonal antibodies and polyclonal antisera recognizing a 39-kda protein (p39) of brucellin, a cytoplasmic extract from brucella melitensis rough strain b115, were produced. the p39 was purified by anion-exchange chromatography. eleven of fourteen brucella-infected cows whose infections had been detected by the delayed-type hypersensitivity (dth) test with brucellergen also developed a dth reaction when purified p39 was used as the trigger. the t-cell proliferative responses to p39 of peripher ... | 1997 | 9009303 |
| protection against infection in mice vaccinated with a brucella abortus mutant. | this study determines whether a genetically engineered mutant of brucella abortus, strain m-1, possesses differences in protective properties compared to the parental strain, vaccine s19. m-1 is a mutant unable to express bp26, a periplasmic protein with potential use in diagnosis. mice vaccinated with s19 developed antibodies against bp26, while those vaccinated with m-1 did not. however, mice vaccinated with s19 or m-1 were similarly protected against challenge with pathogenic strain 2308, sug ... | 1997 | 9009345 |
| serological survey for diseases in free-ranging coyotes (canis latrans) in yellowstone national park, wyoming. | from october 1989 to june 1993, we captured and sampled 110 coyotes (canis latrans) for various diseases in yellowstone national park, wyoming (usa). prevalence of antibodies against canine parvovirus (cpv) was 100% for adults (> 24 months old), 100% for yearlings (12 to 24 months old), and 100% for old pups (4 to 12 months old); 0% of the young pups (< 3 months old) had antibodies against cpv. presence of antibodies against canine distemper virus (cdv) was associated with the age of the coyote, ... | 1997 | 9027690 |
| bacterial survival, lymph node pathology, and serological responses of bison (bison bison) vaccinated with brucella abortus strain rb51 or strain 19. | from august 1993 to june 1994, 3 month-old bison (bison bison) were vaccinated with brucella abortus strain rb51 (srb51, n = 6), strain 19 (s19, n = 3), or with saline (n = 1) and serologic responses and persistence of vaccine strains within lymph nodes were monitored. bison vaccinated with s19 had granulomatous lymphadenitis and greater peak numbers of b. abortus than those vaccinated with srb51. bison vaccinated with rb51 had similar histological lesions and b. abortus were still present in ly ... | 1997 | 9027704 |
| natural resistance to infection with intracellular pathogens: the nramp1 protein is recruited to the membrane of the phagosome. | the nramp1 (natural-resistance-associated macrophage protein 1) locus (bcg, ity, lsh) controls the innate resistance or susceptibility of mice to infection with a group of unrelated intracellular parasites which includes salmonella, leishmania, and mycobacterium. nramp1 is expressed exclusively in professional phagocytes and encodes an integral membrane protein that shares structural characteristics with ion channels and transporters. its function and mechanism of action remain unknown. the intr ... | 1997 | 9034150 |
| production and characterization of monoclonal antibodies specific for the lipopolysaccharide of escherichia coli o157. | identification of the o157 antigen is an essential part of the detection of escherichia coli o157:h7, which is recognized as a major etiologic agent of hemorrhagic colitis. however, polyclonal antibodies produced against e. coli o157:h7 lipopolysaccharide (lps) may react with several other bacteria including brucella abortus, brucella melitensis, yersinia enterocolitica o9, escherichia hermannii, and stenotrophomonas maltophilia. we produced eight monoclonal antibodies (mabs) specific for the lp ... | 1997 | 9041412 |
| comparison of t cell cytokines in resistant and susceptible mice infected with virulent brucella abortus strain 2308. | c57bl/10 and balb/c mice differ in their abilities to clear infections with the intracellular bacterium brucella abortus strain 2308. we have previously reported that in vivo of il-10 in the susceptible balb/c mice results in significantly fewer bacteria in their spleens 1 week after infection with 5 x 10(3) colony forming units (cfu) of 2308. here we extend those studies and report a similar effect when il-4 is neutralized. in contrast, in the more resistant c57bl/10 mice infected with 5 x 10(3 ... | 1996 | 9116636 |
| characterization of smooth lipopolysaccharides and o polysaccharides of brucella species by competition binding assays with monoclonal antibodies. | previously, four epitope specificities on the o chain of brucella species were reported: m, a, c, and c/y. in this work, according to monoclonal antibody binding to smooth lipopolysaccharides of yersinia enterocolitica 0:9, brucella abortus w99 (a-dominant strain), and b. melitensis rev1 (m-dominant strain), seven o-chain epitope specificities were defined: m, a, c (m > a), c (m = a), c/y (m > a), c/y (m = a) and c/y (a > m). competitive binding assays between these monoclonal antibodies suggest ... | 1997 | 9125584 |
| survey of free-ranging elk from wyoming and montana for selected pathogens. | from december 1991 through january 1995, a disease survey was conducted on herds of free-ranging, hunter-killed elk (cervus elaphus nelsoni) from three areas in proximity to yellowstone national park (ynp), wyoming (usa), after tuberculosis caused by mycobacterium bovis was discovered in a captive herd of elk in the area. complete or partial sets of specimens from 289 elk collected between december 1991 and january 1993 were examined histologically; no mycobacterial lesions were observed. lesion ... | 1997 | 9131561 |
| safety and immunogenicity of brucella abortus strain rb51 vaccine in pregnant cattle. | to determine the safety and immunogenicity of brucella abortus strain rb51 as a vaccine in pregnant cattle. | 1997 | 9140553 |
| cloning and nucleotide sequence analysis of a brucella abortus gene encoding an 18 kda immunoreactive protein. | a dna fragment encoding an approximately 18 kda protein from brucella abortus strain 2308 was cloned and expressed in escherichia coli. this recombinant protein, designated ba18k, reacted in western blot analysis with sera obtained from experimentally and naturally infected animals including mice, goats, dogs and humans. restriction enzyme analysis of the plasmid (pba28) encoding ba18k revealed the presence of an approximately 8.7 kbp sau3a genomic dna fragment within the vector and subsequent s ... | 1997 | 9140920 |