Bayesian inferences for receiver operating characteristic curves in the absence of a gold standard     

Young-Ku Choi  Wesley O. Johnson  Michael T. Collins  Ian A. Gardner 《Journal of Agricultural, Biological & Environmental Statistics》2006,11(2):210-229

Sensitivity and specificity are used to characterize the accuracy of a diagnostic test. Receiver operating characteristic (ROC) analysis can be used more generally to plot the sensitivity versus (1-specificity) over all possible cutoff points. We develop an ROC analysis that can be applied to diagnostic tests with and without a gold standard. Moreover, the method can be applied to multiple correlated diagnostic tests that are used on the same individual. Simulation studies were performed to assess the discrimination ability of the no-gold-standard method compared with the situation where a gold standard exists. We used the area under the ROC curve (AUC) to quantify the diagnostic accuracy of tests and the difference between AUCs to compare their accuracies. In particular, we can estimate the prevalence of disease/infection under the no-gold-standard method. The method we proposed works well in the absence of a gold standard for correlated test data. Correlation affected the width of posterior probability intervals for these differences. The proposed method was used to analyze ELISA test scores for Johne’s disease in dairy cattle.  相似文献   

Biomarker changes with systolic anterior motion of the mitral valve in cats with hypertrophic cardiomyopathy     

Joonbum Seo  Jessie Rosie Payne  Jose Novo Matos  Wesley Wynne Fong  David J. Connolly  Virginia Luis Fuentes 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(5):1718-1727

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Identification and isolation of psittacid herpesvirus from psittacids in Brazil     

Luppi MM  Luiz AP  Coelho FM  Malta Mde C  Preis IS  Ecco R  da Fonseca FG  Resende M 《Veterinary microbiology》2011,154(1-2):69-77

Psittacid herpesvirus (PsHV) was isolated from 41 birds kept in captivity in Belo Horizonte, Minas Gerais/Brazil using chicken embryo fibroblasts (CEF) cell cultures. For this study, leukocytes or cloacal swabs of live birds were used. Also, portions of liver, spleen or kidney from birds collected at necropsy were utilized for these tests. PCR tests confirmed the presence of PsHV in 100% of samples. Thirty-three of the PCR products were sequenced and the results disclosed a 99% and 100% identity when compared with other sequences PsHV-1 (AY372243.1 and AF261756.1), previously deposited in GenBank. In addition, histopathology was performed and 19 of the 29 birds contained random multifocal lymphoplasmacytic hepatitis with necrotic foci, suggestive of viral infection. Three samples were examined by electron microscopy to visualize the viral particles obtained from cell culture. The viral structures measured 269 nm in average, had envelopes with an icosahedral capsid and tegument, consistent with herpesvirus. Thus, a total of 41 isolates were obtained from PsHV cell cultivation in CEF, confirming the circulation of the virus between parrots kept in captivity in Belo Horizonte, and affirming the importance of further studies in this area.  相似文献   

Effect of condensed tannin ingestion in sheep and goat parotid saliva proteome     

Lamy E  da Costa G  Santos R  Capela e Silva F  Potes J  Pereira A  Coelho AV  Baptista ES 《Journal of animal physiology and animal nutrition》2011,95(3):304-312

Saliva appears as a defence mechanism, against potential negative effects of tannins, in some species of animals which have to deal with these plant secondary metabolites in their regular diets. This study was carried out to investigate changes in parotid saliva protein profiles of sheep (Ovis aries) and goats (Capra hircus), induced by condensed tannin ingestion. Five Merino sheep and five Serpentina goats were maintained on a quebracho tannin enriched diet for 10 days. Saliva was collected through catheters inserted on parotid ducts and salivary proteins were separated by two-dimensional gel electrophoresis. Matrix-assisted Laser desorption ionization - time of flight (MALDI-TOF) and liquid chromatography tandem mass spectrometry (LC-MS/MS) were used to identify the proteins whose expression levels changed after tannin consumption. Although no new proteins appeared, quebracho tannin consumption increased saliva total protein concentration and produced changes in the proteome of both species. While some proteins were similarly altered in both species parotid salivary protein profile, sheep and goats also presented species-specific differences in response to tannin consumption.  相似文献   

Immune response in sows given transmissible gastroenteritis virus or canine coronavirus   总被引：2，自引：0，他引：2  

R D Woods  R D Wesley 《American journal of veterinary research》1986,47(6):1239-1242

Twelve pregnant sows were inoculated oral-nasally 8 weeks before farrowing with attenuated transmissible gastroenteritis virus (TGEV), tissue culture-adapted canine coronavirus (CCV), or fluids from mock-infected culture (controls). A 2nd dose of the same inoculum, one-half oral-nasally and one-half intramammarily, was given 6 weeks later. Neutralizing antibodies for TGEV and CCV were demonstrated in sera, colostrum, and milk whey from the virus-vaccinated sows. Homologous geometric mean neutralizing titers were generally 4-fold higher than were heterologous titers. After challenge exposure of the nursing pigs with virulent TGEV, average morbidity and mortality for the pigs were 81% and 34% (mortality range = 11% to 63%), respectively, in the TGEV-vaccinated group; 83% and 39% (mortality range = 15% to 83%), respectively, in the CCV-vaccinated group; and 97% and 84% (mortality range = 78% to 100%), respectively, in the controls. Seemingly, sera from swine exposed to CCV could test serologically positive for TGEV-neutralizing antibody, and TGEV and CCV share at least 1 common neutralizing determinant that may be involved in protection.  相似文献   

Occurrence of coligranulomatosis in coturnix quail in Uberlandia, Minas Gerais, Brazil     

P L da Silva  H E Coelho  S C Ribeiro  P R Oliveira 《Avian diseases》1989,33(3):590-593

The occurrence of coligranulomatosis in a Brazilian flock of 1500 8-to-12-month-old coturnix quail is described. The disease caused an 85% drop in egg production and 15% mortality. Lesions were located on the mesentery, intestines, gizzard, heart, oviducts, ovaries, and liver. Samples of these organs were submitted for bacteriological culture, isolation, identification, pathogenicity assay by inoculation of diluted cultures into healthy hens, and histopathology.  相似文献   

Neutralizing antibody decay and lack of contact transmission after inoculation of 3- and 4-day-old piglets with porcine respiratory coronavirus.     

Ronald Wesley 《Journal of veterinary diagnostic investigation》2002,14(6):525-527

Ten female neonatal piglets were infected with porcine respiratory coronavirus (PRCV) to measure the decay of a specific neutralizing antibody. By 42 weeks after exposure,1 of the gilts was serologically negative (< 5) for PRCV, and by 48 weeks 2 more gilts were serologically negative. These data demonstrate that young mature gilts can be serologically negative, yet they could have been exposed to PRCV. Sentinel pigs were commingled with the PRCV-infected pigs at 8 weeks after exposure, and no virus transmission occurred.  相似文献   

Chronic vomiting associated with a gastric carcinoid in a cat.     

John H Rossmeisl  S Dru Forrester  John L Robertson  Wesley T Cook 《Journal of the American Animal Hospital Association》2002,38(1):61-66

A geriatric domestic shorthair cat was presented for evaluation of chronic vomiting. Chronic renal failure was diagnosed on the basis of physical examination findings and results of a serum biochemical profile and urinalysis. Endoscopically obtained gastric biopsies were suggestive of a carcinoid tumor. Subsequently, an exploratory celiotomy with partial gastrectomy was performed. Histopathological and electron microscopic analysis of surgical biopsy specimens confirmed the diagnosis of a gastric carcinoid, which has not been previously reported in the cat. Following complete excision, the cat remained clinically stable and free of signs of gastrointestinal disease for 4 months before requiring treatment for progressive renal failure.  相似文献   

Identification and characterization of aquaporin-9 (AQP9) in porcine hepatic tissue and hepatocytes in monolayer culture     

Caperna TJ  Shannon AE  Richards MP  Garrett WM  Talbot NC 《Domestic animal endocrinology》2007,32(4):273-286

Aquaporins (AQPs) are members of a large family of integral membrane proteins involved in the rapid movement of water and neutral solutes across cell membranes. In this study, we have prepared an affinity-purified porcine-specific polyclonal antiserum to AQP9 and have investigated the distribution and expression of AQP9 in pig liver tissue and in hepatocytes in primary culture. Immunocytochemical analysis showed that AQP9 was primarily localized in the membrane structures of hepatocytes and was not associated with intrahepatic bile ducts or blood vessels. Western blot analysis indicated that AQP9 ranged in apparent molecular mass between 27 and 38 kD in whole liver and hepatocyte membrane fractions; minor components were also observed at approximately 34 kD in the cytosol compartment of hepatocytes, bile duct and gall bladder. A prominent immunoreactive band at 44 kD was shown to be an artifact of Western blot analysis. In primary cultures of porcine hepatocytes, glucagon enhanced absolute levels of AQP9 protein, while gene expression was enhanced by T3 and glucagon. Insulin alone had no discernable influence on AQP9 gene expression or its cellular protein levels. These data suggest that AQP9 is a major AQP in porcine hepatic tissue and appears to be primarily responsive to glucagon induction.  相似文献   

The current status and outlook for insecticide,acaricide and anthelmintic resistances across the Australian ruminant livestock industries: assessing the threat these resistances pose to the livestock sector     

AC Kotze  PW Hunt 《Australian veterinary journal》2023,101(9):321-333

The Australian ruminant livestock industries are faced with the need to control parasitic infectious diseases that can seriously impact the health of animals. However, increasing levels of resistance to insecticides, anthelmintics and acaricides are substantially reducing the ability to control some of these parasites. Here we review the current situation with regard to chemical resistances in parasites across the various sectors of the Australian ruminant livestock industries and assess the level of threat that these resistances pose to the sustainability of these sectors in the short to long terms. We also look at the extent to which testing for resistance occurs across the various industry sectors, and hence how well-informed these sectors are of the extent of chemical resistance. We examine on-farm management practices, breeding of parasite-resistant animals, and non-chemical therapeutics that may act as short to long term means to reduce the current reliance on chemicals for parasite control. Finally, we look at the balance between the prevalence and magnitude of current resistances and the availability and adoption rates of management, breeding and therapeutic alternatives in order to assess the parasite control outlook for the various industry sectors.  相似文献