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101.
C.E. Medina‐Torres J.S. Weese H.R. Staempfli 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2010,24(3):628-632
Background: Clostridium difficile infection (CDI) is a recognized cause of colitis in the horse. Identification of its toxins is important for management of individual cases and for prevention of transmission and zoonosis. In humans, CDI diagnosis is performed with enzyme immunoassays, none of which have been validated for horses. Hypothesis/Objectives: (1) Establish which test for CDI diagnosis was more frequently used by diagnostic laboratories, (2) determine the identified test's performance, sensitivity, and specificity, and (3) validate its use in diarrheic horses. Animals: Samples were obtained from 72 horses presented with acute diarrhea and hospitalized at the Ontario Veterinary College, University of Guelph. Methods: A survey was conducted to establish which of the tests for CDI diagnosis in horses is most commonly used throughout North America. A questionnaire was sent to all laboratories registered in the Veterinary Infection Control Society and the American Association of Veterinary Laboratory Diagnosticians. The performance of the test was evaluated by comparison to a cell cytotoxicity assay (CTA), the accepted Gold Standard for C. difficile toxin detection. Results: The Techlab C. difficile Tox A/B II ELISA was the most frequently used test. Compared with the CTA, no significant difference was observed, and a good level of agreement (93%) was obtained. The diagnostic performance of the ELISA test was adequate (84% sensitivity and 96% specificity). Conclusions and Clinical Importance: Results demonstrate that the Techlab C. difficile Tox A/B II ELISA is a reliable, adequate, and practical tool for identification of C. difficile toxins in horse feces. 相似文献
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AIM:To evaluate the diagnostic value of serum miR-21 as a molecular biomarker in the patients with diabetic nephropathy (DN). METHODS:Twenty-five patients with DN, 50 patients with type II diabetes [divided into DMA group and DMB group base on urinary microalbumin (UmAlb), 25 in each group], 25 patients with diabetic nephropathy-induced uremia (UM) and 25 normal controls (NC) were included in the study. Total RNA was extracted from the serum samples for determining the miR-21 level using real-time PCR. The relationship between miR-21 level and clinical parameters of the patients with diabetic nephropathy was analyzed. RESULTS:The relative expression level of serum miR-21 was significantly lower in DN group than that in DMA group, DMB group and NC group, and was significantly higher than that in UM group (all P<001). The serum miR-21 level showed significant negative correlation with cystatin C, UmAlb, UmAlb/urinary creatinine in DN patients (P<0.01,P<0.05,P<0.05). For discriminating the DN patients from NC, DMA, DMB, DMA+NC, DMB+NC and DMA+DMB, the areas under the receiver operating characteristic curve (AUC-ROC) for serum miR-21 were 0848 (95% CI: 0737~0959), 0896 (95% CI: 0812~0980), 0782 (95% CI: 0641~0922), 0838 (95% CI: 0743~0933), 0796 (95% CI: 0675~0917) and 0808 (95% CI: 0704~0911), and the sensitivity and specificity were 800% and 720%, 720% and 880%, 720% and 840%, 760% and 770%, 760% and 820%, 700% and 860%, respectively. For discriminating the DN patients from DMA+DMB+NC, the AUC-ROC was 0845 (95% CI: 0752~0939), and the sensitivity and specificity were 760% and 773%, respectively. CONCLUSION: Serum miR-21 can serve as a molecular diagnostic marker for diagnosis of diabetic nephropathy. 相似文献
104.
《Communications in Soil Science and Plant Analysis》2012,43(12):1227-1248
Abstract In a relationship between the grain yields and concentrations of a nutrient element at a well defined stage of development under varying growing conditions, i.e. 2.0 g Dry Matter weight (DMw) per hill, the boundary line concept dictates that the grain yield corresponding to the points along the boundary of data points is predominantly determined by the varying concentrations of the respective nutrient element. These concentrations, defined as “Pure‐effect Concentrations,”; form the bases to develop the pure‐effect yield curves. Pure‐effect yield curves were developed for N, P, K, Ca, Mg and Na. The absolutely optimal concentrations or absolute reference values, i.e. the concentrations of various nutrient elements at 2.0 g DMw level corresponding to maximum grain yield, were found to be 3.3% N, 0.36% P, 3.9% K, 1.3% Ca, 0.25% Mg and 0.03% Na. The relationships were developed between the concentrations of other nutrient elements corresponding to pure‐effect concentrations of a nutrient element in question in all combinations by treating each nutrient element as pure‐effect nutrient at a time. These relationships enable one to determine the varying optimal concentrations of other nutrient elements corresponding to the concentrations of the pure‐effect nutrient. These concentrations are defined as “Relatively Optimal Concentrations”; or “Relative Reference Values.”; The absolute and relative reference values are the bases for developing the diagnosis and yield prognosis models which can be used to evaluate the nutritional status of lowland rice plants and to predict the grain yield based on the elemental composition of plants at 2.0 g DMw per hill. The procedure for the application of diagnosis and yield prognosis models is demonstrated. A very good agreement was found between the grain yield predicted by using these models and the actual yields, thus indicating a high degree of accuracy in predicting the grain yield. 相似文献
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Maria Zoraida Daltro de Oliveira Vera Vale Lara Keid Songeli Menezes Freire Roberto Meyer Ricardo Wagner Portela Stella Maria Barrouin-Melo 《Research in veterinary science》2011,90(3):425-431
In the present study, the validation of an enzyme-linked immunosorbent assay (ELISA) for serodiagnosis of canine brucellosis is described. Two different antigenic extracts, obtained by heat or ultrasonic homogenization of microbial antigens from a wild isolate of Brucella canis bacteria, were compared by ELISA and Western blot (WB). A total of 145 canine sera were used to define sensitivity, specificity and accuracy of the ELISA as follows: (1) sera from 34 animals with natural B. canis infection, confirmed by blood culture and PCR, as well as 51 sera samples from healthy dogs with negative results by the agar–gel immunodiffusion (AGID) test for canine brucellosis, were used as the control panel for B. canis infection; and (2) to scrutinize the possibility of cross reactions with other common dog infections in the same geographical area in Brazil, 60 sera samples from dogs harboring known infections by Leptospira sp., Ehrlichia canis, canine distemper virus (CDV), Neospora caninum, Babesia canis and Leishmania chagasi (10 in each group) were included in the study. The ELISA using heat soluble bacterial extract (HE-antigen) as antigen showed the best values of sensitivity (91.18%), specificity (100%) and accuracy (96.47%). In the WB analyses, the HE-antigen showed no cross-reactivity with sera from dogs with different infections, while the B. canis sonicate had various protein bands identified by those sera. The performance of the ELISA standardized with the heat soluble B. canis antigen indicates that this assay can be used as a reliable and practical method to confirm infection by this microorganism, as well as a tool for seroepidemiological studies. 相似文献
107.
Epizootic heamorragic disease 总被引:1,自引:0,他引:1
Savini G Afonso A Mellor P Aradaib I Yadin H Sanaa M Wilson W Monaco F Domingo M 《Research in veterinary science》2011,91(1):1-17
Epizootic haemorrhagic disease (EHD) is an infectious non-contagious viral disease transmitted by insects of the genus Culicoides which affects wild and domestic ruminants. The causative agent, the epizootic haemorrhagic disease virus (EHDV), belongs to the family Reoviridae, genus Orbivirus and shares many morphological and structural characteristics with the other members of the genus such as bluetongue, African horse sickness and equine encephalosis viruses. In recent years EHD outbreaks have been reported in countries bordering the European Union. They caused disease in cattle and severe repercussion on the livestock industry of the affected countries. In the light of recent European bluetongue epizootic these events pose an increasing threat to the European Union. This review includes the most recent information regarding the virus and the disease as well as tools for its diagnosis and control. It is our conviction that more attention should be drawn to both EHDV and the disease itself in order to fulfil all these gaps and not to be unprepared in case future possible incursions. 相似文献
108.
泰安周边某奶牛场先后有8头奶牛发病,临床症状疑似狂犬病症状。采集死亡牛小脑、大脑皮层、大脑海马回等部位的脑组织进行常规切片染色。结果表明,在小脑、大脑海马角神经细胞的胞浆内发现嗜酸性包涵体,证实该奶牛发病为狂犬病毒感染。 相似文献
109.
为确诊贵州省都匀市某养殖场的猪死亡病因,采集病死猪病料进行猪繁殖与呼吸综合征病毒、猪瘟病毒、猪伪狂犬病病毒、猪圆环病毒2型核酸检测,细菌分离鉴定及药物敏感试验。结果:猪繁殖与呼吸综合征病毒实时荧光定量RT-PCR检测和猪圆环病毒2型PCR检测核酸均为阳性,其余病毒核酸检测均为阴性。细菌分离培养表明存在细菌感染,分子生物学鉴定为奇异变形杆菌;分离菌对硫酸安普霉素、硫酸粘菌素、盐酸大观霉素+盐酸林可霉素、氟苯尼考较敏感,对多种药物产生耐药。结论:确诊病例为猪繁殖与呼吸综合征病毒、猪圆环病毒2型、奇异变形杆菌混合感染。 相似文献
110.