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71.
Effects of human recombinant interleukin-1beta on canine articular chondrocytes in three-dimensional culture 总被引:1,自引:0,他引:1
Cook JL Anderson CC Kreeger JM Tomlinson JL 《American journal of veterinary research》2000,61(7):766-770
OBJECTIVE: To determine the effects of interleukin (IL)-1beta on matrix synthesis and degradation by chondrocytes cultured in a 3-dimensional (3-D) gel medium. SAMPLE POPULATION: Chondrocytes from 7 dogs. PROCEDURE: Articular chondrocytes were harvested and cultured in 3-D gel medium alone or with 10 or 20 ng IL-1beta/ml that was added beginning on day 0, 3, 6, or 9. On days 3, 6, 12, and 20 of 3-D culture, samples of the liquid medium were evaluated for glycosaminoglycan (GAG), prostaglandin E2 (PGE2), and matrix metalloprotease (MMP)-3 content. The 3-D plug in each well was evaluated for histologic characteristics of viability, cell morphology, and proteoglycan staining, immunohistochemically stained for collagen type II, and spectrophotometrically analyzed for GAG content. RESULTS: Significant differences for all variables were detected between controls and each IL-1beta group, among groups with different IL-1beta concentrations, and among groups with IL-1beta added at various time points. Chondrocytes exposed to IL-1beta had loss of GAG, increased PGE2 and MMP-3 concentrations, and lack of collagen type-II synthesis. These IL-1beta effects appeared to be time and concentration dependent. CONCLUSIONS: Addition of IL-1beta to chondrocytes in 3-D gel medium results in time- and concentration-dependent effects on matrix synthesis and degradation and provides an appropriate in vitro model for many of the pathophysiologic events associated with osteoarthritis. 相似文献
72.
The case records of 37 cats treated for nasopharyngeal or aural inflammatory polyps were reviewed. Thirty of them were managed conservatively with the polyp being removed by traction alone. Long-term follow-up information was available for 22 cats, of which 13 (59 per cent) had no recurrence of clinical signs. The remaining nine cats required recurrent polyps to be removed surgically. Cats with only nasopharyngeal polyps were nearly four times more likely to be cured by traction alone than cats with aural polyps, and none of the cats that was treated with prednisolone after traction suffered a recurrence. Cats with more severe aural signs were more likely to require surgery. 相似文献
73.
Rohde C Anderson DE Desrochers A St-Jean G Hull BL Rings DM 《Veterinary surgery : VS》2000,29(4):341-346
OBJECTIVE: To compare synovial fluid characteristics of cattle with infectious and noninfectious arthritis. STUDY DESIGN: Retrospective cohort study. ANIMAL OR SAMPLE POPULATION: 130 cattle. METHODS: Synovial fluid was analyzed for total nucleated cell count (NCC), absolute number and percentages of polymorphonuclear (PMN) and mononuclear cells, total protein (TP) concentration, and specific gravity. Cattle were categorized as having infectious or noninfectious arthritis based on physical and lameness examinations, joint radiographs, and microbial culture results. Kruskal-Wallis 1-way analysis of variance was used to compare synovial fluid analysis data from different categories. Selection of cut-off values for the calculation of likelihood ratios, sensitivity, specificity, and positive and negative predictive values was based on examination of the distribution of the data using histograms. RESULTS: Cattle with infectious arthritis had significantly higher numbers of total NNC, PMN cells, TP concentration, and specific gravity (P = .0001) and a significantly higher percentage of PMN cells compared with cattle with noninfectious arthritis (P = .0001). The percentage of mononuclear cells was significantly higher in cattle with noninfectious arthritis (P = .0001). CONCLUSIONS: Synovial fluid analysis is useful for differentiation of infectious and noninfectious causes of joint disease in cattle. CLINICAL RELEVANCE: Cattle with a synovial fluid total NCC > 25,000 cells/microL, a PMN cell count > 20,000 cells/microL or more than 80% PMN cells, and TP > 4.5 g/dL should be considered to have infectious arthritis. 相似文献
74.
Efficacy of doramectin against naturally acquired nematode infection in Iberian swine 总被引:7,自引:0,他引:7
Studies were carried out to determine the therapeutic efficacy of doramectin, administered intramuscularly at a dose of 300 microg/kg live weight, against naturally acquired helminths of extensively farmed Iberian pigs. The first study (slaughter study) evaluated, through necropsy of the study animals, the product's efficacy against gastrointestinal and pulmonary nematodes (Ascaris suum, Oesophagostomum dentatum and Metastrongylus sp.) whilst the second, faecal egg count reduction study, (FECR study) evaluated the drug's efficacy only against gastrointestinal helminths (A. suum, Trichuris suis and Oesophagostomum sp.).The first study used 20 animals divided into two equal groups of 10 on the basis of body weight and faecal egg count. One group constituted saline treated controls and the other was doramectin treated. On Day 14 post treatment half of the animals in each group were necropsied and the number of parasites present counted. On Day 15 the remaining half of each group underwent the same procedure. The second study was carried out with 40 animals divided equally into two groups of 20. This study determined the effect of doramectin treatment on faecal egg counts as an indicator of parasite burden.The first study demonstrated an efficacy of 100% against adult Metastrongylus sp. and A. suum, whilst the efficacy against O.dentatum was 96.3%. The second study indicated that at Day 21 post treatment there was a 100% reduction in egg counts in faeces in comparison to untreated controls. 相似文献
75.
Prevalence of Salmonella in beef feeder steers as determined by bacterial culture and ELISA serology
Galland JC House JK Hyatt DR Hawkins LL Anderson NV Irwin CK Smith BP 《Veterinary microbiology》2000,76(2):143-151
Results are presented for monitoring Salmonella infection by bacteriological culture and immune response (enzyme linked immunosorbent assay (ELISA) and haptoglobin) testing of samples collected from beef cattle at a single feedyard sampled over time. A total of 120 beef steers were examined on entry to the feedyard and at days 30, 60, and at time of slaughter (120-150 days). Isolations of Salmonella decreased over time from 40% of the steers sampled at day 0 to 0% at slaughter, whereas serological results varied by serogroup. Seropositivity increased for Salmonella group B up to day 60, and subsequently decreased to about half of the 60-day positivity rate at the time of slaughter. No significant changes in seropositivity were detected during the course of the study for the four other Salmonella serogroups (C1, C3, D1, and E1). Haptoglobin measurements were not a good indicator of Salmonella infection status. Sequential Salmonella testing either by culture, ELISA, or both could be used to monitor pathogen control practices. 相似文献
76.
Bailey BA Apel-Birkhold PC Akingbe OO Ryan JL O'Neill NR Anderson JD 《Phytopathology》2000,90(8):812-818
ABSTRACT The fungus Pleospora papaveracea and Nep1, a phytotoxic protein from Fusarium oxysporum, were evaluated for their biocontrol potential on opium poppy (Papaver somniferum). Four treatments consisting of a control, P. papaveracea conidia, Nep1 (5 mug/ml), and P. papaveracea conidia plus Nep1 (5 mug/ml) were used in detached-leaf and whole-plant studies. Conidia of P. papaveracea remained viable for 38 days when stored at 20 or 4 degrees C. Nep1 was stable in the presence of conidia for 38 days when stored at 4 degrees C or for 28 days at 20 degrees C. The presence of Nep1 did not affect conidia germination or appressoria formation. Nep1 was recovered from drops applied to opium poppy leaves in greenhouse and field studies 24 h after treatment. Opium poppy treated with the combination of Nep1 and P. papaveracea had higher necrosis ratings than the other treatments. There were changes in the intercellular protein profiles, determined by sodium dodecyl sulfate gel electrophoresis and silver staining, due to application of treatments; the most intense occurred in response to the combination of Nep1 and P. papaveracea. The combination of Nep1 and P. papaveracea enhanced the damage caused to opium poppy more than either component alone. 相似文献
77.
Bailey BA Apel-Birkhold PC O'Neill NR Plaskowitz J Alavi S Jennings JC Anderson JD 《Phytopathology》2000,90(7):699-709
ABSTRACT Two pathogenic fungi of opium poppy, Pleospora papaveracea and Dendryphion penicillatum, were isolated from field material in Beltsville, MD. The processes of infection by these two fungi were studied to determine the optimal environmental conditions for infection. Both fungi formed appressoria capable of penetrating directly through the plant epidermal layer. Of the two fungi, P. papaveracea was more aggressive, causing more rapid necrosis. Appressorial formation by P. papaveracea occurred as early as 4 h after application of a conidial suspension to poppy leaves. P. papaveracea formed more appressoria than did D. penicillatum, especially at cool temperatures (7 to 13 degrees C). In greenhouse studies, P. papaveracea caused more damage to opium poppy than did D. penicillatum when applied in 10% unrefined corn oil. In the field, P. papaveracea was more consistent in its effects on opium poppy from a local seed source designated Indian Grocery. P. papaveracea caused higher disease ratings, more stem lesions, and equal or greater yield losses than did D. penicillatum on Indian Grocery. The late-maturing opium poppy variety White Cloud was severely damaged by disease, regardless of formulation or fungal treatment. P. papaveracea was the predominant fungus isolated from poppy seed capsules and the only fungus reisolated from the field the following year. These studies provide a better understanding of the infection process and the differences between these two pathogenic fungi and will be beneficial for the development of the fungi as biological control agents. 相似文献
78.
Roy D Berghaus Thomas B Farver Randall J Anderson John M Adaska Ian A Gardner 《Journal of veterinary diagnostic investigation》2006,18(3):233-242
Cows from 2 California dairies were tested for paratuberculosis at the end of lactation by using fecal culture and a commercially available serum enzyme-linked immunosorbent assay (ELISA) test kit. Individual cow characteristics and production variables were evaluated along with ELISA testing results as predictors of fecal culture status. In multivariable logistic regression analysis, age and a herd-standardized version of 305-day mature equivalent (305 ME) milk production were significant predictors of fecal culture status after adjusting for herd, quarter of the study year, and ELISA sample-to-positive (S/P) ratio. The area under a nonparametric receiver operating characteristic curve was significantly greater for a multivariable model that included age and the level of milk production when compared with a model without these covariates. In conclusion, consideration of cow-level covariates was useful as an aid in predicting Mycobacterium avium ssp. paratuberculosis (MAP) fecal culture status. For a given ELISA S/P ratio, older cows and those with lower 305 ME milk production relative to other cows in the herd were significantly more likely to be shedding MAP in their feces at the end of lactation. 相似文献
79.
Prediction of multinomial probability of land use change using a bisection decomposition and logistic regression 总被引:1,自引:1,他引:1
Land use change is an important research area in landscape ecology and urban development. Prediction of land use change (urban
development) provides critical information for making the right policies and management plans in order to maintain and improve
ecosystem and city functions. Logistic regression is a widely used method to predict binomial probabilities of land use change
when just two responses (change and no-change) are considered. However, in practice, more than two types of change are encountered
and multinomial probabilities are therefore needed. The existing methods for predicting multinomial probabilities have limits
in building multinomial probability models and are often based on improper assumptions. This is due to the lack of proper
methodology and inadequate software. In this study, a procedure has been developed for building models to predict the multinomial
probabilities of land use change and urban development. The foundation of this procedure consists of a special bisection decomposition
system for the decomposition of multiple-class systems to bi-class systems, conditional probability inference, and logistic
regression for binomial probability models. A case study of urban development has been conducted to evaluate this procedure.
The evaluation results demonstrated that different samples and bisection decomposition systems led to very similar quality
and performance in the developed multinomial probability models, which indicates the high stability of the proposed procedure
for this case study. 相似文献
80.
A polymelus monster was observed in a 7-week-old slaughterhouse chicken. The supernumerary limbs were smaller than the normal appendages but contained an equal number of digits. 相似文献