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51.
Reasons for performing study: Previous studies suggest that owners underestimate or incorrectly recognise or report health problems in geriatric horses. However, few studies have directly compared owner‐reported and veterinary assessed disease. Objectives: To compare the findings of veterinary clinical examination of geriatric horses with owner‐reported clinical signs and disease. Methods: A total of 200 horses aged ≥15 years were randomly selected to receive a veterinary examination, from responses to a cross‐sectional postal questionnaire survey. Veterinary examinations were performed within 2 months of questionnaire return, and agreement between owner‐reported data and veterinary clinical findings was assessed. Results: Owners under‐reported many clinical signs and disease conditions detected on veterinary clinical examination. For example, dental abnormalities (detected in 95.4% of horses, reported by 24.5% of owners); cardiac murmurs (detected in 20% of horses, reported by 0.5% of owners); lameness (present in 50% of horses, reported by 23% of owners) and hoof abnormalities (detected in 80% of horses, reported by 27% of owners). Agreement between owner‐reported and veterinary assessed respiratory disease (Kappa 0.02–0.2), body condition score (Kappa 0.24) and coat abnormalities (Kappa 0.42) was poor, fair and moderate, respectively. Range of motion (ROM) of the tarsal and metacarpophalangeal joints was lower in horses with owner‐reported osteoarthritis (P = 0.005 and <0.001, respectively). Conclusions and potential relevance: The low prevalence and relatively poor agreement of owner‐reported disease compared to that detected on veterinary examination suggests inaccurate or under‐recognition, or inaccurate reporting of health problems by owners of geriatric horses, which could lead to a delay in presentation for veterinary treatment. Increased veterinary involvement and improved owner education in the care of geriatric horses should facilitate earlier identification of disease, particularly that which is not readily detectable by owners, and aid management of health and welfare problems.  相似文献   
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Susceptibility to branch dieback caused by Phytophthora ramorum was tested using a detached branch assay for 66 Australian native plant species sourced from established gardens and arboreta in California. Six of these species were further tested for their susceptibility to bole cankers caused by P. ramorum using a sealed log assay. Isopogon formosus and Eucalyptus denticulata were identified as potentially highly susceptible Australian branch dieback hosts. Thirteen potentially tolerant Australian host species included Banksia attenuata, B. marginata, E. haemastoma, E. regnans, Pittosporum undulatum and Billardiera heterophylla. Eucalyptus regnans was identified as a potentially highly susceptible bole canker host, while E. diversicolor and E. viminalis were considered potentially tolerant species to bole cankers caused by P. ramorum. Phytophthora ramorum was able to infect all 66 species, as confirmed by reisolation. These results extend the known potential host range for P. ramorum, confirm it as a possible threat to Australian plant industries and ecosystems and highlight additional associated hosts that are important in the global horticultural trade, native forests and plantation forestry.  相似文献   
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Reasons for performing study: With growing numbers of aged horses, geriatric medicine is becoming increasingly important in equine veterinary practice; however, there is a paucity of information on the UK equine geriatric population. Objectives: To describe the demographic characteristics of the equine geriatric population and to assess management practices undertaken by owners of geriatric horses (aged ≥15 years). Methods: A cross‐sectional study was conducted, surveying a randomly selected sample of veterinary registered owners with horses aged ≥15 years, using a self‐administered postal questionnaire. Results: Horses aged ≥15 years represented 29% of the equine population in the study area. The response rate to the questionnaire survey was 80.2%. Management practices were similar to those previously described for the general equine population. However, the level of exercise and feeding practices changed significantly with increasing age. A summary of the demographic characteristics, feeding and management of horses in a sample of the geriatric equine population is presented. Conclusions and potential relevance: The management of geriatric horses has a direct effect on their health and welfare and this study has provided valuable information on the demographics and management of geriatric horses and ponies in the UK. The information can be used to form targeted owner education programmes for geriatric health and should aid in the investigation and prevention of disease.  相似文献   
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Four new tetromycin derivatives, tetromycins 1-4 and a previously known one, tetromycin B (5) were isolated from Streptomyces axinellae Pol001(T) cultivated from the Mediterranean sponge Axinella polypoides. Structures were assigned using extensive 1D and 2D NMR spectroscopy as well as HRESIMS analysis. The compounds were tested for antiparasitic activities against Leishmania major and Trypanosoma brucei, and for protease inhibition against several cysteine proteases such as falcipain, rhodesain, cathepsin L, cathepsin B, and viral proteases SARS-CoV M(pro), and PL(pro). The compounds showed antiparasitic activities against T. brucei and time-dependent inhibition of cathepsin L-like proteases with K(i) values in the low micromolar range.  相似文献   
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L-selectin (CD62L) gene expression in neutrophils is commonly referred to as "constitutive" because circulating neutrophils require a constant supply of this adhesion molecule for continuous trafficking into peripheral tissues. Under normal circumstances, marginating blood neutrophils and neutrophils that become activated for migration into infected tissues rapidly shed surface CD62L that is ligated to the vascular endothelium. However, this does not shut down CD62L gene expression because these cells continue to express surface CD62L. In contrast, glucocorticoid challenges resulting from stress and hormone injections result in gradual and chronic down-regulation of CD62L on the surface of blood neutrophils. Rather than being associated with migration, this type of CD62L down-regulation associates with pronounced neutrophilia and increased susceptibility to infections. Nothing is currently known about glucocorticoid regulation of CD62L expression in neutrophils. In other cell systems, however, this steroid hormone binds to cytoplasmic glucocorticoid receptors (GR) that influence expression of glucocorticoid-responsive genes at multiple pre-translational levels. Thus, the hypothesis of the present study was that glucocorticoid challenge suppresses CD62L mRNA expression in blood neutrophils. Suppressed CD62L gene expression might help explain the chronic down-regulation of surface CD62L in neutrophils and accompanying neutrophilia. The main objectives of the study were to monitor neutrophil CD62L mRNA abundance before and during subtle and severe glucocorticoid challenges and to determine if CD62L mRNA expression correlates with degree of glucocorticoid challenge. Parturient dairy cows and dexamethasone-treated steers were used as models of subtle and severe (respectively) glucocorticoid challenges. Data presented from both models support the hypothesis and show for the first time that glucocorticoids regulate neutrophil CD62L at a pre-translational level. Results also showed that inhibited CD62L mRNA expression correlated precisely with down-regulated surface expression of CD62L on neutrophils and peak neutrophilia during severe glucocorticoid challenge. Therefore, results of this study indicate that bovine neutrophils are highly sensitive to the blood environment, displaying full capacity to alter CD62L gene expression and trafficking patterns in response to changing glucocorticoid levels. This may serve animals well when heightened inflammatory responses begin to lead to tissue damage, but may be detrimental to overall health if animals are exposed to opportunistic pathogens while stressed or undergoing glucocorticoid therapy. Although this study did not elucidate how glucocorticoids inhibit neutrophil CD62L mRNA expression, presented data implicate GR as possibly being involved because neutrophils from cattle in both models expressed GR mRNA. Further in vitro studies using purified populations of neutrophils will be required to determine if GR is directly involved in glucocorticoid regulation of CD62L gene expression and, if so, at what level.  相似文献   
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