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Differential reactivity of bovine lymphocytes to species of Brucella
1990
Smith, R. III. | Kapatsa, J.C. | Sherwood, S.J. III. | Ficht, T.A. | Templeton, J.W. | Adams, L.G.
The reactivity of bovine lymphocytes to 4 species of Brucella was tested in thymidine-uptake assays, using long-term cultured lymphocytes and freshly obtained blood mononuclear cells. Lymphocytes were taken from cows that had been challenge exposed with a virulent strain of B abortus at midgestation. The cows were classified retrospectively as being naturally resistant or susceptible to brucellosis. Lymphocytes taken from these cows had 3 patterns of reactivity with species of Brucella: pattern 1 was defined by reactivity with 4 species (B abortus, B canis, B suis, and B melitensis); pattern 2 was defined by reactivity with all these species, except B melitensis; pattern 3 was defined by reactivity with B abortus and B canis, but not with B suis or B melitensis. There was a statistically significant correlation between susceptibility to brucellosis and expression of lymphocyte cross-reactivity with B suis (P < 0.01) and with B melitensis (P < 0.001).
Mostrar más [+] Menos [-]Chemical and protective properties of Brucella lipopolysaccharide obtained by butanol extraction
1989
Phillips, M. | Pugh, G.W. Jr | Deyoe, B.L.
Lipopolysaccharide (LPS) fractions were obtained from smooth cultures of Brucella abortus strains 2308 and S-19 by butanol extraction procedures. The LPS from the initial butanol extraction contained 10 to 15% protein and was reduced to less than 1% protein by treatment with proteinase K. The LPS fractions were identified and characterized on the basis of the chemical analysis, sodium dodecyl sulfate gel electrophoresis, cesium chloride gradients, electron microscopy, and gel immunodiffusion. Results indicated that the butanol procedure is a reliable method in the extraction of LPS from Brucella abortus cells. Proteinase K-treated LPS containing less than 1% protein from strain 2308 was used to vaccinate BALB/cByJ mice. Immune and protective criteria for vaccinated and nonvaccinated mice were increased immunoglobulin (IgG and IgM) titers in sera of prechallenge-exposed mice, reduced colony-forming units/spleen, and splenomegaly in post-challenge-exposed mice. Results indicated that proteinase K-treated LPS was immunuogenic as well as protective for mice.
Mostrar más [+] Menos [-]Protection of mice against Brucella abortus infection by inoculation with monoclonal antibodies recognizing Brucella O-antigen
1989
Phillips, M. | Deyoe, B.L. | Canning, P.C.
Monoclonal antibodies recognizing the O-polysaccharide portion of Brucella abortus strain 2308 provided BALB/c mice with passive protection against challenge exposure with the homologous strain. Numbers of colony-forming organisms in the spleen were reduced by IgM and IgG monoclonal antibodies. Active immunization of mice, using B abortus 2308S lipopolysaccharide, resulted in production of IgM antibody at 14 days. Clearance of organisms in the actively immunized mice after challenge exposure at 14 days was nearly identical to that in passively immunized mice. Mice either passively or actively immunized were effectively protected from 0 to 28 days. Bacterial colonization of the spleen was observed to increase in both groups of mice at 56 days and indicated that humoral responses were effective in eliminating the organism in the early stages of infection, but other immune mechanisms were necessary for protection of mice in the later stage of infection with virulent strains of B abortus.
Mostrar más [+] Menos [-]Investigation of Brucellosis Information and Applications of Animal Breeders: The Case of Erdemli
2020
Tollu, G.
Lack of information about brucellosis can affect patient’s health-seeking behaviors and thuscause constant infectation in semi-urban communities. This study aimed to determine the knowledge levelof brucellosis of dairy cattle breeders and evaluate the information about brucellosis in 83 people living in21 different villages and neighborhoods of Erdemli district. In the study, in this cross-sectional study, face to face interviews and data were collected using a 30 question questionnaire to investigate the level of knowledge about individuals aboutbrucellosis. Data were evulated by using SPSS 21.0 statistic program.While 72.3% the individuals do not know that brucellosis causes disease in humans, 56.6% do notknow that it causes disease in animals. Participants said that 56.6% had heard of the about brucellosis beforeand those who heard said that they had heard from 13.3% of their relatives or neighbors. A majority of theparticipants (56.6 %) had heard about Brucella, 72.3% of individuals do not know that brucellosis causesdisease in humans and 56.6% of the participants do not know that Brucella is an animal disease. It wasdetermined that 65 (73.8%) of the participants did not make cheese from raw milk, 66 (79.5%) did notconsume cheese fresh, and 74 (89.2%) did not make butter from raw milk cream. The individuals whoparticipated of in the study 32.5% had bovine animals and 67.5% had small ruminants; the rate of abortedanimals is 30.1% in the last year. The total proportion 20.5% was of stillbirths, the rate 51.8% was infertileanimals.In the present study infertility, stillbirth and abortion numbers of individuals who had notheard of brucellosis before were higher than those who had heard and who took the necessary precautions.It is a fact that the herd can threaten all other animals in rapidly spreading infectious diseases such asbrucellosis. Therefore, providing the necessary incentives for the establishment of modern business facilitiesin areas where animal husbandry is intensive, if this is not possible, raising the level of knowledge byproviding various trainings to individuals dealing with dairy cattle breeding will contribute to the nationaleconomy.
Mostrar más [+] Menos [-]Protective efficacy of an inactivated Brucella abortus vaccine candidate lysed by GI24 against brucellosis in Korean black goats
2019
Kim, W. K. | Moon, J. Y. | Cho, J. S. | Ochirkhuvaq, E. | Akanda, M. R. | Park, B. Y. | Hur, H.
The efficacy of GI24-lysed Brucella abortus cells as a vaccine candidate against brucellosis in goats was evaluated on 2 groups of Korean black goats. Group A goats were immunized subcutaneously (SC) with sterile phosphate-buffered saline, whereas group B goats were immunized SC with approximately 3 × 10(9) lysed B. abortus cells. Subcutaneous immunization with the lysed cells did not cause any negative impact on the overall clinical status, such as behavior and appetite, throughout the study period. The enzyme-linked immunosorbent assay (ELISA) optical densities values for B. abortus lipopolysaccharide in serum were considerably higher in group B than those in group A. Also, the levels of the cytokines interleukin 4 (IL-4), tumor necrosis factor-alpha (TNF-α), and interferon gamma (IFN-γ) were significantly elevated in group B compared with those in group A. Following intraconjunctival challenge with B. abortus strain 544, the severity of brucellosis in terms of infection index and colonization of B. abortus in tissues was significantly lower in group B than in group A. The present study concluded that 3 of 5 goats immunized with GI24-lysed bacteria were completely protected against challenge. Future investigations are required to improve the protective efficacy offered by lysed B. abortus cells for practical applications in small ruminants.
Mostrar más [+] Menos [-]A quantitative investigation of knowledge and practices of human brucellosis in Kajiado County, Kenya
2017
Maina, A. G. | Gatongi, P. M. | Nguhiu, P. N.
Human brucellosis, a neglected zoonosis is endemic in KajiadoCounty in both man and livestock. The Kajiado County community’s mainlivelihood is livestock-keeping which puts it at risk. The study objective was to determine the community’s knowledge and practices, and the association between the two in relation to brucellosis. Results revealed three predictors of practices the community undertook that put them at risk of contracting brucellosis. The predictors were respondent’s education status (p=0.002 [CI 0.272-0.749] OR 0.451), knowledge of importance of pre-purchaselivestock breeding soundness (p=0.007 [CI 1.207-3.356] OR 2.013), and knowledge that livestock abortions could result in human disease (p=0.027 [CI 1.070-2.974] OR 1.783). This meant that respondents without formal education were nearly half less likely to undertake practices that prevented transmission of brucellosis than those withformal education. Respondents who knew that livestock examination was important for breeding soundness were twice more likely to engage in practices that prevented brucellosis transmission than those whodid not know. Respondents who knew that livestock abortions could lead to diseases in man were nearly twice more likely to engage in practices that prevented transmission of brucellosis than those whodid not know that livestock abortions could lead to diseases in man. It was concluded that the community’s knowledge and practices that promote brucellosis were inadequate. Two key recommendationswere drawn. There was need to create awareness in the community on the risk factors and practices that contribute to occurrence of human brucellosis. There was need for using qualified animal health providers to mitigate the disease in animals.
Mostrar más [+] Menos [-]Whole genome sequence of Brucella melitensisl local isolate from an infected goat in Malaysia
2016
Mohd Mokhtar Arshad | Ramlan Mohamed | Shuhaila Mat Sharani | Hardy Abu Daud | Omer Khazaal Sallou | Mohd Azam Khan Goriman Khan | Hirzahida Mohd. Padil
Brucellosis in goats is mainly caused by the bacterium Brucellamelitensis, which is one of the most important pathogenic species in the world. In Malaysia, the annual prevalence data of brucellosis was recorded in goats and the control strategy of the disease basedon test and cull of infected animals. This strategy has caused huge economic losses to farmers and government alike. Therefore, whole genome sequencing of B. melitensis local strain is essential forimproving the current vaccine. B. melitensis strain VRI 6530/11 wasobtained from veterinary research institute biobank, Ipoh. The strain was submitted for classical identification procedures and the total genomic DNA was extracted by using DNeasy blood and tissue kit(QIAGEN). The concentration and purity of DNA were determined by using agarose gel electrophoresis and spectrophotometer (DNA/RNA) assay respectively. The genome was sequenced by using IlluminaHiSeq platform with insert size ~200 bp. A total of 1.0 Gb data was generated from the sample. More than 95% of sequencing data was retained in the sample after quality filtering, this indicatethe sequencing reads are of high quality. Final assembly had 33 scaffolds with total size ~3.28 Mb, 44 contigs, GC content is 57.25%, N50 is 293,291. A total of 3,238 protein coding genes, 48 tRNAs and 3rRNAs were predicted and over 87% of the genes were functionally annotated. Genome sequencing of a local B. melitensis strain is the first of its kind in Malaysia and work from this study can contribute towards the development of a new effective vaccine for the control ofthe disease in the country.
Mostrar más [+] Menos [-]Serological prevalence of brucellosis of cattle in selected dairy farms in Bangladesh
2014
Hassan, A., Department of Medicine, Faculty of Veterinary and Animal Science, Sylhet Agricultural University, Sylhet, Bangladesh | Uddin, M. B., Department of Medicine, Faculty of Veterinary and Animal Science, Sylhet Agricultural University, Sylhet, Bangladesh | Islam, M.R., Department of Medicine, Faculty of Veterinary and Animal Science, Sylhet Agricultural University, Sylhet, Bangladesh | Cho, H.S., Chungnam National University, Daejeon, Republic of Korea | Hossain, M.M., Department of Medicine, Faculty of Veterinary and Animal Science, Sylhet Agricultural University, Sylhet, Bangladesh
This study was conducted to investigate the status of brucellosis in dairy cattle from five selected dairy farms in the Mohammadpur Beribadh area of Bangladesh. A cross-sectional study was carried out from October 2010 to March 2011 in which a total of 334 serum samples from cattle in five herds were screened by the Rose-Bengal plate-agglutination test (RBPT) and the positives were confirmed using an indirect enzyme-linked immunosorbent assay (I-ELISA). A structured questionnaire was used to collect epidemiological information describing the animals. Overall, 4.20% of the animals were RBPT positive, while subsequent confirmatory tests with I-ELISA revealed that the overall animal-level prevalence derived from the samples was 1.20%. Additionally, the prevalence was relatively higher in females than in males. A significant association was found between abortion, age of the animals, and the occurrence of brucellosis (p 0.05). Considering the overall low prevalence of brucellosis in the selected farms in the present study, a brucellosis eradication program for dairy farms using a test-and-slaughter policy would be possible.
Mostrar más [+] Menos [-]Use of indirect enzyme-linked immunosorbent assay with hot saline solution extracts of a variant (M-) strain of Brucella canis for diagnosis of brucellosis in dogs
1993
Mateu-de-Antonio, E.M. | Martin, M. | Soler, M.
An ELISA, using hot saline solution extracts (HSS) of a less-mucoid variant (M -) strain of Brucella canis as antigen, was developed for detection of antibodies against B canis in dogs. The test was applied to 177 field serum samples previously tested by use of the 2-mercaptoethanol rapid slide agglutination test, 2- mercaptoethanol-tube agglutination test, and agar gel -immunodiffusion containing HSS and cytoplasmic antigens of B canis. Results indicated that this ELISA seems to be highly specific (95.6%) and slightly less sensitive (93.8%). The HSS obtained from B canis wild-type RM 6/66 also have been used, but in our study, it seemed to be unsuitable for use in ELISA because of the high background values observed for sera with negative test results.
Mostrar más [+] Menos [-]Treatment of Brucella melitensis infection in mice by use of liposome-encapsulated gentamicin
1989
Hernandez-Caselles, T. | Vera, A. | Crespo, F. | Villalain, J. | Gomez-Fernandez, J.C.
Liposomes with entrapped gentamicin were used to treat mice with infection attributable to Brucella melitensis. Liposomes bearing positive charge and formed by egg yolk lecithin, cholesterol, and stearylamine were effective in the elimination of B melitensis residing in liver and spleen. Negatively charged liposomes, formed by egg yolk lecithin, cholesterol, and dicetyl phosphate were also effective in suppression of the infection in liver, but were less so in suppression of the infection in the spleen. Free gentamicin was less effective than the encapsulated antibiotic. At 20 hours after administration of gentamicin encapsulated in liposomes, the gentamicin concentrations in liver and spleen were similar, regardless of the charge of the liposomes--neutral, positive, or negative. However, positively charged liposomes were more efficient than were other liposome types for the treatment of brucellosis caused by B melitensis.
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