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Application of pulsed-field gel electrophoresis for differentiation of vaccine strain RB51 from field isolates of Brucella abortus from cattle, bison, and elk
1995
Jensen, A.E. | Cheville, N.F. | Ewalt, D.R. | Payeur, J.B. | Thoen, C.O.
Restriction endonuclease patterns of genomic fragments separated by use of pulsed-field gel electrophoresis were used to differentiate Brucella abortus strain RB51, a rifampin-resistant mutant of the standard virulent strain 2308, from other brucellae. Results were compared with results obtained by use of standard methods for characterizing brucellae. Electrophoretic patterns of the ATCC type strains allowed identification of the strains to the level of species. Genomic profiles of B abortus biovars 1, 2, and 4 were similar, as were those of biovars 5, 6, and 9. The profile of biovar 3 was similar to that of biovars 5, 6, and 9, except for a missing band at 93 kb and additional bands at 65 and 67 kb. A different fingerprint was detected in B abortus strain RB51, using the pulsed-field gel electrophoresis patterns of genomic DNA digested with restrictive endonuclease Xba I. The profile of B abortus strain RB51 contained a band at 104 kb, as opposed to a 109-kb fragment within profiles of B abortus isolates from naturally infected cattle, bison, and elk. Despite known biochemical and biological differences between RB51 and its parent strain (2308), restriction endonuclease analysis results were similar.
显示更多 [+] 显示较少 [-]Effect of bacterial lipopolysaccharides on sulfated glycosaminoglycan metabolism and prostaglandin E2 synthesis in equine cartilage explant cultures
1994
MacDonald, M.H. | Stover, S.M. | Willits, N.H. | Benton, H.P.
The metabolic responses of equine articular cartilage to incubation with bacterial lipopolysaccharide (LPS) were studied, using explant cultures of articular cartilage obtained from the metatarsophalangeal joints of 15 horses, age of which ranged from 3 months to 20 years. For comparison, explants were also established from the metatarsophalangeal joints of 3 calves. Explants were cultured for 3 days in medium containing various concentrations of LPS from 0 (control) to 100 microgram/ml. Glycosaminoglycan (GAG) released during the 3-day incubation was determined by a spectrophotometric assay, using the dye 1,9-dimethylmethylene blue. Newly synthesized GAG content was assayed by measuring [35S]sulfate incorporation during a 3-hour pulse labeling period. In addition, prostaglandin E2 (PGE2) synthesis was quantified, using a [3H]PGE2 radioimmunoassay kit and magnetic separation. Finally, explants from 3 animals were used to evaluate the effect of supplementing culture medium with 5% serum on the response of explants to LPS, and explants from 1 horse were used to compare responses to stimulation with LPS derived from 2 bacterial sources. Equine explants cultured with bacterial LPS had a dose-dependent decrease in synthesis and increase in release of GAG, and these responses were significantly (P < 0.0001) greater in explants from younger horses. In addition, equine explants had a significant (P = 0.0001) dose-dependent increase in concentration of PGE2 released into the culture medium in response to incubation with LPS. Comparison of data for GAG synthesis from equine and bovine explants revealed a significant (P = 0.025) difference in responsiveness to LPS between the 2 species. Equine explants tended to have a greater suppression of GAG synthesis in response to incubation with increasing concentrations of LPS than did age-corrected bovine samples. However, similar analysis of data on GAG release did not indicate any difference in sensitivity between the 2 species for this response. There was no evidence that the presence or absence of serum supplementation or the use of LPS derived from different bacterial sources made a significant difference in the response of explants to incubation with LPS.
显示更多 [+] 显示较少 [-]High-resolution computed tomography of the mammalian lung
1992
Chen, Q. | Klein, J.S. | Gamsu, G. | Webb, R.
High-resolution computed tomography (HRCT) was performed in 21 isolated animal lungs, from 4 mammalian species (pigs, rabbits, dogs, sheep). Gross and subgross central and peripheral lung morphology was determined by HRCT. Three distinct types of lungs can be identified, principally based on the extent of interlobular septal development; the relationship of major vessels to airways; and the thickness of the visceral pleura. Type-I lung is found in pigs, sheep, and cattle; type-II lung is found in rabbits, dogs, cats, and monkeys; and type-III lung is found in human beings and horses. These mammalian lungs were compared with human lungs. The potential use of HRCT to investigate specific human lung diseases in the aforementioned species also was considered.
显示更多 [+] 显示较少 [-]Isolation of a major form of pepsinogen from gastric mucosa of horses
1991
Khittoo, G. | Vermette, L. | Nappert, G. | Lariviere, N.
In mammalian species studied previously, pepsinogen consisted of biochemically different groups of isozymogens. By use of gel filtration chromatography and electrophoresis, we isolated a predominant pepsinogen from the gastric mucosa of a horse. Peptide mapping with V8 protease revealed differences with its porcine homologue. However, porcine and equine pepsinogens, when activated to pepsin, had a similar pattern of activity when hemoglobin was used as substrate. Those results suggest that differences must exist in the primary structure of the pepsinogens of the 2 species.
显示更多 [+] 显示较少 [-]Seroprevalence of ovine progressive pneumonia virus in various domestic and wild animal species, and species susceptibility to the virus
1991
Cutlip, R.C. | Lehmkuhl, H.D. | Brogden, K.A. | Schmerr, M.J.F.
Ovine progressive pneumonia is caused by a lentivirus of known infectivity only for sheep and goats. Virus susceptibility of 11 other species of animals was examined. Species included cattle, chickens, deer, dogs, goats, hamsters, horses, mice, pigs, rabbits, and rats. Of these species, only goats and rabbits could be experimentally infected with the virus. The infection in rabbits was acute, and virus did not persist or induce antibody production as it does in sheep and goats. Sera obtained from several people working in close contact with the virus and from several wild species, with unknown exposure history, were tested for antibodies to viral antigens. All results were negative. Knowledge of the host range of this virus is important for scientific studies and for virus eradication programs.
显示更多 [+] 显示较少 [-]Proto-oncogenes of genomic DNA in clinically normal animals of various species
1991
Miyoshi, N. | Tateyama, S. | Ogawa, K. | Nosaka, D. | Ohashi, T. | Sunyasootcharee, B.
To provide information about oncogenes for molecular biological studies of tumors in domestic animals, theproto-oncogenes homologous to the c-myc, c-erbB-2, c-ros-1, c-yes-1, v-myc, v-Ki-ras, and v-Ha-ras oncogenes of genomic DNA in cattle, horses, pigs, dogs, cats, and chickens were investigated by Southern blot hybridization. High molecular weight genomic DNA in each of the animals contained proto-oncogenes that had a certain homology with the oncogenes used, but the extent of nucleotide homology of the proto-oncogenes differed in number and molecular weight: ie, 1 or 2 bands at 1.6 to 22.0 kilobase (kb) in the c-myc probe, 1 or 2 bands at 1.1 to 16.0 kb in the c-ros-1 probe, 1 to 3 bands at 0.7 to 23.0 kb in the c-erbB-2 probe, 1 to 4 bands at 0.6 to 18.0 kb in the c-yes-1 probe, 1 to 3 bands at 1.6 to 30.0 kb in the v-myc probe, 1 to 7 bands at 1.0 to 36.0 kb in the v-Ki-ras probe, and 1 to 4 bands at 1.0 to 27.0 kb in the v-Ha-ras probe. Furthermore, signal strength of each band, as determined by autoradiography, was not always the same for each probe in the various animals. Our findings indicate that these proto-oncogenes are well conserved with species specificities in each animal.
显示更多 [+] 显示较少 [-]Comparison of humoral immunity and induction of proliferating T lymphocytes in vaccinia virus-infected rabbits and rhesus macaques
1994
Schaffner, J.W. | Dittmer, U. | Otteken, A. | Coulibaly, C. | Bodemer, W. | Voss, G. | Hunsmann, G.
Vaccina virus (VV) infection induces specific antibodies and cytotoxic T cells in various animal species. Therefore, helper T cells also should be induced that stimulate the humoral and cellular immune responses. We determined such helper T-cell activity in 2 species after VV infection. Rabbits and rhesus macaques were infected with the Copenhagen strain of VV or with recombinant VV expressing retroviral proteins. Animals of both species developed antibodies and specific proliferative T-cell response. This reactivity could be enhanced by booster infection with VV. The proliferating macaque cells were CD4+ and major histocompatability complex class II-restricted. These data confirm the broad immunogenicity of VV. Expression of additional polypeptides expressed from a recombinant VV does not lead to altered immune response to VV antigens. However, strength of the helper T-cell response, as well as clinical reactions, differed between macaques and rabbits. Infection with recombinant VV as delivery vectors offers the opportunity for combined vaccination against recombinant proteins and does not diminish cellular and humoral immune responses to VV itself.
显示更多 [+] 显示较少 [-]Host factors affecting seroprevalence of bluetongue virus infections of cattle
1994
Ward, M.P. | Carpenter, T.E. | Osburn, B.I.
Results of testing of 19,731 samples from a serologic survey of cattle with bluetongue virus (BTV) infections in Australia were analyzed for association between age, species, or sex and test result. Bivariate analysis indicated that all 3 host factors were associated with test result. After adjusting for confounding caused by the location of each animal in the study (high, moderate, and low BTV prevalence regions), cattle greater than or equal to 4 years old had an odds ratio of 4.33 (95% confidence interval, 3.99, 4.71) for a positive test result, compared with that for cattle < 2 years old. Cattle 2 to 4 years had an odds ratio of 2.28 (2.14, 2.54), compared with cattle < 2 years old. Bos taurus cattle had an odds ratio of 1.76 (1.63, 2.05) of a positive test result, compared with crossbred cattle, and B indicus cattle had an odds ratio of 1.20 (1.09, 1.33), compared with crossbred cattle. Sexually intact (+) male cattle were found to have an odds ratio of 3.13 (2.66, 3.49) for a positive test result, compared with castrated male (-) cattle, and female cattle were found to have an odds ratio of 1.38 (1.29, 1.48), compared with male (-) cattle. Multivariate analysis of BTV testing results was performed, using stepwise logistic regression. The most parsimonious model selected included age, species, and sex factors, and first-order interaction terms between these factors. This model was only able to be fit to data from cattle restricted to the high (> 25%) BTV prevalence region. Odds ratios were found to increase with age for male (-) cattle of all species. Odds ratios were found to be greatest at 2 to 4 years of age for female cattle of all species and for B taurus and crossbred male (+) cattle.
显示更多 [+] 显示较少 [-]Tonometry of normal eyes in raptors
1994
Stiles, J. | Buyukmihci, N.C. | Farver, T.B.
An applanation tonometer was used to estimate intraocular pressure in normal eyes of several species of raptors. No bird had active injury or illness, though some were nonreleasable to the wild because of previous injury. Mean (+/- SD) intraocular pressure was 20.6 (+/- 3.4) mm of Hg in red-tailed hawks (Buteo jamaicensis, n = 10), 20.8 (+/- 2.3) mm of Hg in Swainson's hawks (Buteo swainsoni, n = 6), 21.5 (+/- 3.0) mm of Hg in golden eagles (Aquila chrysaetos, n = 7), 20.6 (+/- 2.0) mm of Hg in bald eagles (Haliaeetus leucocephalus, n = 3), and 10.8 (+/- 3.6) mm of Hg in great horned owls (Bubo virginianus, n = 6). There was no significant difference in intraocular pressure between hawks and eagles. Mean pressure in great horned owls was significantly (P < 0.01) lower than pressure in hawks or eagles. Reliable intraocular pressure readings could not be obtained in barn owls (Tyto alba).
显示更多 [+] 显示较少 [-]Comparison of the properties and concentrations of the isoforms of retinol-binding protein in animals and human beings
1993
Burri, B.J. | Neidlinger, T.R. | Zwick, H.
We used size-exclusion high-performance liquid chromatography (HPLC) to investigate the properties of the 2 isoforms of vitamin A-containing (holo) retinol-binding protein (RBP) in animals: the form that is bound to transthyretin (holo-TTR-RBP), and the form that does not bind to TTR (holo-free RBP). We also used radial immunodiffusion to measure immunologically active RBP (apo+ holo RBP). We compared the isoforms of RBP in animals with those of human beings to determine which animal is the best model of human RBP. Size-exclusion HPLC detected holo-free and holo-TTR-RBP in every animal species studied. Apparent concentration of holo-TTR-RBP varied among species: that of rabbits and dogs much greater than that of apes, sheep, goats, monkeys, rhinoceroses, felids, rats, human beings, and deer greater than that of pigs, zebra, and bison greater than that of penguins. Dogs have unusual RBP chromatograms; they have high concentration of RBP, but also appear to transport much of their vitamin A on proteins other than RBP, Human RBP antibody preparations could detect apo + holo RBP immunologic activity only in apes, monkeys, and felids. Apes and monkeys appeared to have complete cross-reactivity to human RBP antibodies. Felids may have substantial, but partial, cross-reactivity. Apes and monkeys appear to be the most relevant animal models for study of human RBP transport. However, there is a need for less-expensive models. Further research is needed, but in the interim, rats or sheep may be satisfactory for some purposes.
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