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101.
C. M. Cannon M. C. Scott D. Ito B. H. Gorden A. J. Graef J. F. Modiano 《Veterinary and comparative oncology》2015,13(1):48-59
We evaluated the effect of Aurora kinase inhibitors AZD1152 and VX680 on canine osteosarcoma cells. Cytotoxicity was seen in all four cell lines; however, half‐maximal inhibitory concentrations were significantly higher than in human leukaemia and canine lymphoma cells. AZD1152 reduced Aurora kinase B phosphorylation, indicating resistance was not because of failure of target recognition. Efflux mediated by ABCB1 and ABCG2 transporters is one known mechanism of resistance against these drugs and verapamil enhanced AZD1152‐induced apoptosis; however, these transporters were only expressed by a small percentage of cells in each line and the effects of verapamil were modest, suggesting other mechanisms contribute to resistance. Our results indicate that canine osteosarcoma cells are resistant to Aurora kinase inhibitors and suggest that these compounds are unlikely to be useful as single agents for this disease. Further investigation of these resistance mechanisms and the potential utility of Aurora kinase inhibitors in multi‐agent protocols is warranted. 相似文献
102.
Cannon WB 《Science (New York, N.Y.)》1933,78(2012):43-48
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Spring wheat (Triticum aestivum L.) dry matter (DM), N content and tillering are increased by increasing the proportion of N available to the plant as NH4 (enhanced ammonium supply‐EAS) at soil pH ≥ 7.0. Using different N sources to provide different levels of EAS effects soil pH and electrical conductivity (EC) as well as soil NH4. Both pH and EC may affect plant growth and response to EAS. Two greenhouse experiments were conducted to determine the effects of EAS, pH, and EC on the DM, N content, and tillering of spring wheat. The collinearity between pH and NH4 was eliminated over a pH range of 5.8 to 7.2 by adjusting lime rates to compensate for the effect of each N source on pH. Even though EC was somewhat correlated with soil NH4 in both experiments, there were a sufficient number of comparisons to separate the effects of EC and NH4 on plant growth. Differences in plant growth resulted from differences in soil NH4 levels. Soil pH and EC did not affect plant growth. Plant responses to soil NH4 levels were quadratic. Maximum plant growth occurred at approximately 100–200 mg/kg KCl‐extractable NH4. 相似文献
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CASE HISTORY: A neonatal Thoroughbred foal was presented with rib fractures and left forelimb lameness secondary to dystocia. CLINICAL FINDINGS: The foal developed a head tilt, seizures and watery diarrhoea during hospitalisation and died at 7 days of age. Histological examination of the brain and spinal cord revealed a suppurative meningoencephalomyelitis with vasculitis, and numerous intralesional, gram-negative bacilli. Similar microscopic lesions were noted in the lungs, renal medullary interstitium, and umbilicus. Bacilli in the brain, spinal cord and umbilicus were identified immunohistochemically as Salmonella group B. Salmonella agona was isolated in pure culture from the brain, lung, liver, kidney, and intestine. CONCLUSION: This is the first report of meningoencephalomyelitis and septicaemia due to Salmonella infection in an equine neonate. 相似文献
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J Sarabia Fragoso M Pizarro Díaz JC Abad Moreno P Casanovas Infesta A Rodriguez‐Bertos K Barger 《Reproduction in domestic animals》2013,48(2):345-352
In a farm of grandparent broiler breeder chickens, we followed the development of 350 roosters from 6 to 55 weeks of age. Data collected and evaluated from these males included body weight, testicular weight, histologic and immunohistochemistry studies of the testes, hormone levels (testosterone, estradiol and corticosterone) and sperm production. The objective was to understand the factors that affect or influence hatch loss that is commonly observed after 45 weeks of age in breeder flocksare often correlated to broiler breeder male chickens. The results of this study showed that in conjunction with the weight of the rooster, the testicle weight increases quickly after the rooster receives light stimulation. At an older age, the study showed that there is a process of testicular shrinkage, and the same effect is seen in sperm production and testosterone levels in broiler breeder roosters. From the histology evaluation, we defined 5 histologic phases that illustrate the evolution of the testicular tissue: perinatal, infantile, puberty, adult and senile. We observed that the adult males with a body weight <3800 g were infertile or had subfertile levels and also had low levels of testosterone and high levels of corticosterone. In contrast, the heaviest males showed correct testicular vitality, high levels of testosterone and low levels of corticosterone. However, the roosters that had acquired this high body weight were also at risk of having less complete copulations because of their physical mass. The loss of uniformity of the males and the appearance of hierarchies within the flock accompany a decline in the percentages of hatches as a consequence of the poor confirmation of the males for copulation or the restriction to the access to the females. Results of this study show that the decrease in fertility from 45 weeks of age has been associated with a decline in testicular weight, sperm production and the testosterone levels in animals with a sub‐par weight. Likewise, decreasing hatch in older flocks may also result from a loss of conformation, and the lack of complete copulations is possible because of animals that are grossly overweight. 相似文献
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The ovarian follicle components must provide an ideal environment to ensure the success of reproductive processes, and communication between follicular cells is crucial to support proper oocyte growth. Recently, it has been demonstrated that the presence of extracellular vesicles (EVs) carrying microRNAs (miRNAs) in follicular fluid represents an important autocrine and paracrine communication mechanism inside the ovarian follicle. In this study, we tested the hypothesis that the miRNA content of EVs isolated from ovarian follicular (granulosa and cumulus–oocyte complexes) cell‐conditioned culture media is dependent upon cell type. We initially screened bovine granulosa cells (GCs) and cumulus–oocyte complexes (COCs), as well as their derived EVs for 348 miRNAs using real‐time PCR, and detected 326 miRNAs in GCs and COCs cells and 62 miRNAs in GCs and COCs EVs. A bioinformatics analysis of the identified cell‐specific and differentially expressed miRNAs predicted that they likely modulate important cellular processes, including signalling pathways such as the PI3K‐Akt, MAPK and Wnt pathways. By investigating the origins of miRNAs within the follicular fluid, the results of this study provide novel insights into follicular miRNA content and intercellular communication that may be of invaluable use in the context of reproductive technologies, diagnostic of ovarian‐related diseases and/or the identification of biomarkers for oocyte and embryo quality. 相似文献