排序方式： 共有21条查询结果，搜索用时 718 毫秒
1.
Histofarcin, a skin test antigen for the diagnosis of epizootic lymphangitis, was locally produced from the mycelial form of Histoplasma capsulatum var. farciminosum (HCF) in disease-endemic districts of Ethiopia and tested for its application in the field between April 2002 and May 2003. The test was evaluated using 108 mules, 84 in endemic and 24 in disease-free districts. Microscopic and mycological examinations of clinical lesions were used as the "gold standard" for the validation of the test. The concentration of histofarcin that caused an optimum reaction was 0.2-0.4 mg/mL in a 0.1 mL dose and this was attained 24-48 h post-injection. The sensitivity and specificity of the histofarcin test were 90.3% (CI = 73.1, 97.5) and 69% (95%, CI = 48.1, 84.9%) in disease-endemic districts. On the other hand, specificity was 100% (CI=94.8, 100) in disease-free districts. Positive and negative predictive values of the histofarcin test were 77.78% (95% CI = 60.4, 89.3) and 85.71% (95% CI = 62.6, 96.2), respectively. A marginal substantial agreement (kappa = 0.61, P = 0.0000) was observed between the clinical status and the result of the histofarcin test. A large proportion (31%) of 'false positives' was recorded in endemic districts, which could be due to the pre-clinical stage of the disease. The latter ended in lower specificity and positive predictive value of the test since the true infection status of a 'false positive' could not be known on the basis of clinical features. Therefore, standard test validation procedures including slaughtering and isolation of HCF is required. After proper validation, we conclude that the histofarcin test could play a significant role in detecting early infection, and differentiating of EL from glanders, ulcerative lymphangitis, and sporotrichosis. 相似文献
2.
Joram Buza Tadele Kiros Adama Zerihun Isaac Abraham Gobena Ameni 《Veterinary immunology and immunopathology》2009,130(3-4):251-255
Changes in the proportion of peripheral blood T cell subsets after subcutaneous inoculation of cattle with Mycobacterium bovis Bacille Calmette-Guerin (BCG) were studied. Calves were injected with approximately 8 × 106 BCG bacillus and blood samples collected at weekly intervals for flow-cytometric analyses to determine the proportion of CD4+, CD8+ and γδ T cells. In addition, whole blood samples were stimulated in vitro with M. bovis purified protein derivative (PPD) and the secreted IFN-γ quantified by ELISA. Results showed cellular and cytokine changes which could be categorized into three phases. The first phase occurred within the first 2 weeks after vaccination involving an increase in proportion of WC1+ γδ T cells and a concomitant increase in the secretion of IFN-γ. These two responses peaked at 2 weeks and waned thereafter. The second phase involved an increase in the CD4/CD8 ratio as a result of an increase in the proportion of CD4+ T cells between 4 and 6 weeks. The third phase involved a decrease in the CD4/CD8 ratio due to an increase in the proportion of CD8+ T cells between 8 and 10 weeks. Surprisingly, the IFN-γ response was associated with changes in the γδ rather than the CD4+ or CD8+ T cells, suggesting that this cytokine was secreted by γδ-T cells. These results are consistent with the reported ability of γδ T cells to act rapidly and bridging the innate and classically adaptive immune responses. 相似文献
3.
Amal Abdelhamid Sirine Lajili Mohamed Amine Elkaibi Yosra Ben Salem Ameni Abdelhamid Christian D. Muller 《Journal Of Aquatic Food Product Technology》2013,22(9):892-909
Brown seaweeds produce useful bioactive substances with high cosmetic and pharmacological values due to the presence of antioxidant derivatives, mainly phlorotannins (PHT), which are of particular interest. A central composite rotatable design (CCRD) with three variables (extraction time, dry material-to-solvent ratio and ethanol concentration) and two responses was performed to optimize the microwave-assisted extraction (MAE) of phlorotannins from Cystoseira sedoides using response surface methodology (RSM). Results showed that the independent variables significantly affected both phlorotannin content and the scavenging capacity. The optimum operating conditions were extraction time, 101.74 sec; dry material-to-solvent ratio, 1:10 g/mL; and ethanol extraction, 50%. Under these conditions, the predicted values of PHT content and radical scavenging activity-IC50 were close to the observed values and were 383.887 µg PGE/g Dm and 18.353 µg/mL, respectively. Characterization of the phlorotannin-rich fraction was conducted by high-performance liquid chromatography and Fourier transform infrared spectroscopy. The evaluation of the anticancer activity against MCF-7 breast cancer cell line showed a potent activity to trigger apoptotic death in more than a half of the MCF-7 cells, with an estimated IC50 value of 78 μg/mL. In addition, this fraction induced a notable growth regression effect on 3D spheroids model in a concentration-dependent manner, with a growth rate of about 1.17, at 200 µg/mL.Abbreviations: CCRD: Central composite rotatable design; Dm: Dry material; DMBA: 2,4-dimethoxy benzaldehyde; DMSO: Dimethyl sulfoxide; DPPH: 1,1-diphenyl-2-picrylhydrazyl; EDTA: Ethylene diamine tetraacetic acid; FBS: Fetal bovine serum; FT-IR: Fourier transform infrared; HPLC: High-performance liquid chromatography; IC50: Half-maximal inhibitory concentration; MAE: Microwave-assisted extraction; Min: minutes; PBS: Phosphate buffered saline; PGE: Phloroglucinol equivalent; PHT: Phlorotannins; PHT-SED: phlorotannins derived from Cystoseira sedoides; PI: Propidium iodide; RSA: Radical scavenging activity; RSM: Response surface methodology; Sec: seconds 相似文献
4.
Erratum to: A cross-sectional study on bovine tuberculosis in Hawassa town and its surroundings,Southern Ethiopia 总被引：1，自引：1，他引：0
Regassa Alemayehu Tassew Asmelash Amenu Kebede Megersa Bekele Abunna Fufa Mekibib Berhanu Marcotty Tanguy Ameni Gobena 《Tropical animal health and production》2010,42(5):1039-1039
Tropical Animal Health and Production - 相似文献
5.
Gobena Ameni Abraham Aseffa Glyn Hewinson Martin Vordermeier 《Tropical animal health and production》2010,42(3):375-383
Host immune responses to Mycobacterium bovis (M. bovis) infection are variable at the different severity stages of pathology of the disease. In countries like Ethiopia, where routine
screening of bovine TB is not undertaken, the use of tests which measure cellular and antibody responses may help for the
maximum detection of infection. In the present study, 701 cattle were tested for bovine tuberculosis (BTB) using comparative
intradermal tuberculin (CIDT) test, interferon (IFN)-γ test, and lateral flow assay. The apparent prevalence was 32% when
all the three tests were used, but varied from 23 to 25% when a pair of tests was used and from 9% to 15% when a single test
was used. Agreement was observed between CIDT and IFN-γ tests both at a cut-off >2 mm (Kappa ± standard Error, k ± SE, 0.129 ± 0.045; 95%CI = 0.041,0.216) and a cut-off >4 mm (k ± SE, 0.094 ± 0.044, 95%CI = 0.008,0.179) while no agreement was observed either between CIDT test and lateral flow assay
(k ± SE, −0.04 ± 0.033; 95%CI = −0.104,0.024) or between IFN-γ tests and lateral flow assay (k ± SE, −0.031 ± 0.032; 95% CI = −0.093,0.031). Thus, the use of more than one test leads to the detection of the maximum number
of infected animals. 相似文献
6.
A cross-sectional study on bovine tuberculosis in Hawassa town and its surroundings,Southern Ethiopia 总被引：2，自引：2，他引：0
Alemayehu Regassa Asmelash Tassew Kebede Amenu Bekele Megersa Fufa Abunna Berhanu Mekibib Tanguy Macrotty Gobena Ameni 《Tropical animal health and production》2010,42(5):915-920
A cross-sectional study was conducted in Hawassa town and its surroundings from October 2007 to May 2008 to estimate the prevalence
of bovine tuberculosis (BTB) based on comparative interadermal tuberculin test (CIDT) and abattoir survey. Accordingly, 39
herds comprising 413 cattle were subjected to CIDT, and the herd and individual animal prevalence were 48.7% (19/39) and 11.6%
(48/413), respectively. One of the 16 milk samples collected from tuberculin-positive cows was culture positive. The prevalence
significantly differed among the age group (P = 0.001) and management system (P = 0.001). Thus, age group over four (OR = 7.9) and animal with poor management system (OR = 4.1) had a higher odds for tuberculin
reactivity compared to those with age group under four and cattle with good management system, respectively. Of the total
1,023 cattle subjected to postmortem examination, 11 (1.1%) were found to be positive for gross tuberculous lesions. Larger
proportion (50%) of TB lesion was recorded in the respiratory pathway followed by digestive system (28.6%) and prescapular
lymph nodes (21.4%). Of 14 tissue specimens collected from the gross lesions, four (28.6%) were positive for histopathological
TB lesions. In conclusion, this study revealed the importance of BTB in the study area in particular and the region in general. 相似文献
7.
Ameni Ben Zineb Darine Trabelsi Fathi Barhoumi Sana Fitouri Dhane Ridha Mhamdi 《Archives of Agronomy and Soil Science》2020,66(8):1074-1088
ABSTRACT The objective of this study is to evaluate the impacts of the direct use of natural rock phosphates on two forage legumes, Vicia sativa, and Medicago sativa. Crops were grown in pots containing two P deficient soils and fertilized with Tunisian rock phosphate (TRP) or chemical triple superphosphate (TSP). TRP amendment significantly increased shoot dry yield (+53% to +162%), P-content, protein content, and chlorophyll content mainly at the rate of 150 kg P ha?1. No significant effects were observed on mycorrhization and antioxidant enzyme activities. However, TSP negatively affected the frequency of root mycorrhization and stimulated antioxidant enzyme activities. TRP amendment induced an increase in fluorescein diacetate activity, alkaline phosphatase activity, and species richness. The stimulation involved mainly Actinobacteria, Proteobacteria, and Firmicutes with higher stimulation of Actinobacteria in the case of vetch. The present work indicated a better P-use efficiency of vetch. It suggested also that at least a part of the enhancement observed in plant-growth parameters following TRP fertilization is driven by changes in the structure of rhizosphere microbial communities. Nevertheless, the correlation between changes in microbial composition and phosphorus uses efficiency needs to be investigated further. 相似文献
8.
Ameni G Aseffa A Sirak A Engers H Young DB Hewinson RG Vordermeier MH Gordon SV 《The Veterinary record》2007,161(23):782-786
In 2002, the prevalence of bovine tuberculosis (tb) among 500 cattle on Holeta Farm, near Addis Ababa, Ethiopia, was 48 per cent, and the farm was divided into positive and negative herds. After three consecutive rounds of skin testing and segregation of skin test-positive and -negative animals, the prevalence of bovine tb was reduced from 14 per cent to 1 per cent in the negative herd in a year. Spoligotyping of 41 isolates from 17 cows gave an identical and unique spoligotype pattern, which can be represented as the binary number 1100000101111110111111100010000000000100000, where 1 indicates the presence of a spacer and 0 represents a loss. This spoligotype pattern had not previously been reported on the Mycobacterium bovis spoligotype database, and it was therefore designated SB1176, Ethiopian M bovis strain 1 (EMbs1). The variable number tandem repeat (VNTR) profile of the strain was 5254(*)33.1, which differed from the VNTR profile of strains reported in Great Britain. 相似文献
9.
10.
Ameni G 《Veterinary journal (London, England : 1997)》2006,172(1):160-165
A study was conducted between January 2003 and June 2004 on 19,082 carthorses in 28 towns in Ethiopia to investigate the epidemiology of equine histoplasmosis (EH). Clinical and microscopic examinations were used and an overall prevalence of 18.8% (3579/19082) was recorded. Statistically significant (P<0.001) differences was observed in the average prevalence with high, medium, and low prevalence categories. The highest prevalence (39%) was recorded at Mojo while the lowest (0.0%) was recorded at five towns, namely, Agaro, Bokoji, Debre Berhan, Dinsho, and Sagure. The prevalence of EH was not associated (R=0.08, F=0.15, P=0.71) with the mean annual rainfall but was associated (R=0.64, F=11.5, P<0.01) with the average annual temperature. Statistically significant (R=0.57, F=12.34, P<0.01) association was observed between the altitude of the study towns and the prevalence of EH. Moreover, the number of cases of EH increased significantly (R=0.88, F=90.9, P<0.001) with the horse population in the towns. In general, EH was prevalent in hot and humid towns with an altitude ranging from 1500m above sea level (asl) to 2300masl but was nil or low in cold and in dry and windy towns. It was concluded that EH is prevalent in Ethiopia and warrants the initiation of a control strategy. 相似文献