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排序方式: 共有510条查询结果,搜索用时 15 毫秒
81.
Letícia Beatriz Matter Nicolle Lima Barbieri Marcel Nordhoff Christa Ewers Fabiana Horn 《Veterinary microbiology》2011
Avian pathogenic Escherichia coli (APEC) are responsible for extraintestinal diseases, called colibacillosis, in avian species. The most severe manifestation of the disease is colisepticemia that usually starts at the respiratory tract and may result in bird death. However, it is not yet clear how APEC cross the respiratory epithelium and get into the bloodstream. In this work, we studied the interaction between 8 APEC strains (UEL31, UEL17, UEL13, UEL29, MT78, IMT5155, IMT2470, A2363) and a chicken non-phagocytic cell, the fibroblast CEC-32 cell line. We investigated the association profile, the invasion capability, the cytotoxicity effect and the induction of caspase-3/7 activation in an attempt to understand the way the pathogen gains access to the host bloodstream. Association to cells was determined after 1 h of infection, while cell invasion was determined after 4 and 24 h of infection. The cytotoxic effect of bacterial infection was measured by lactate dehydrogenase (LDH) release and the activation of the apoptotic program was verified by caspase-3/7 activation. Also, the presence of genes for adhesins, invasins and other related virulence-associated factors was verified by PCR. All bacterial strains showed similarity in relation to adhesion, LDH release and caspase-3/7 activation. However, one APEC strain, MT78, showed high invasion capability, comparable to the invasive Salmonella typhimurium strain SL1344. Since an APEC strain was capable of invading non-phagocytic cells in vitro, the same may be happening with the epithelial cells of the avian respiratory tract in vivo. CEC-32 monolayers can also provide a useful experimental model to study the molecular mechanisms used by APEC to invade non-phagocytic cells. 相似文献
82.
Azzouz A Jurado-Sánchez B Souhail B Ballesteros E 《Journal of agricultural and food chemistry》2011,59(9):5125-5132
This paper reports a systematic approach to the development of a method that combines continuous solid-phase extraction and gas chromatography-mass spectrometry for the simultaneous determination of 20 pharmacologically active substances including antibacterials (chloramphenicol, florfenicol, pyrimethamine, thiamphenicol), nonsteroideal anti-inflammatories (diclofenac, flunixin, ibuprofen, ketoprofen, naproxen, mefenamic acid, niflumic acid, phenylbutazone), antiseptic (triclosan), antiepileptic (carbamazepine), lipid regulator (clofibric acid), β-blockers (metoprolol, propranolol), and hormones (17α-ethinylestradiol, estrone, 17β-estradiol) in milk samples. The sample preparation procedure involves deproteination of the milk, followed by sample enrichment and cleanup by continuous solid-phase extraction. The proposed method provides a linear response over the range of 0.6-5000 ng/kg and features limits of detection from 0.2 to 1.2 ng/kg depending on the particular analyte. The method was successfully applied to the determination of pharmacologically active substance residues in food samples including whole, raw, half-skim, skim, and powdered milk from different sources (cow, goat, and human breast). 相似文献
83.
Ruiz Maria Luiza Owatari Marco Shizuo Yamashita Marcela Maya Ferrarezi José Victor Saffadi Garcia Patricia Cardoso Lucas Martins Maurício Laterça Mouriño José Luiz Pedreira 《Tropical animal health and production》2020,52(1):167-176
Tropical Animal Health and Production - The aims of this study were to evaluate the inclusion of different concentrations of Lactobacillus plantarum in Nile tilapia diet and to verify histological... 相似文献
84.
Hctor Marina Antonio Reverter Beatriz Gutirrez-Gil Pamela Almeida Alexandre Rocío Pelayo Aroa Surez-Vega Cristina Esteban-Blanco Juan Jos Arranz 《Journal of animal science》2020,98(12)
Sheep milk is mainly intended to manufacture a wide variety of high-quality cheeses. The ovine cheese industry would benefit from an improvement, through genetic selection, of traits related to the milk coagulation properties (MCPs) and cheese yield-related traits, broadly denoted as “cheese-making traits.” Considering that routine measurements of these traits needed for genetic selection are expensive and time-consuming, this study aimed to evaluate the accuracy of a cheese-making phenotype imputation method based on the information from official milk control records combined with the pH of the milk. For this study, we analyzed records of milk production traits, milk composition traits, and measurements of cheese-making traits available from a total of 1,145 dairy ewes of the Spanish Assaf sheep breed. Cheese-making traits included five related to the MCPs and two cheese yield-related traits. The milk and cheese-making phenotypes were adjusted for significant effects based on a general linear model. The adjusted phenotypes were used to define a multiple-phenotype imputation procedure for the cheese-making traits based on multivariate normality and Markov chain Monte Carlo sampling. Five of the seven cheese-making traits considered in this study achieved a prediction accuracy of 0.60 computed as the correlation between the adjusted phenotypes and the imputed phenotypes. Particularly the logarithm of curd-firming time since rennet addition (logK20) (0.68), which has been previously suggested as a potential candidate trait to improve the cheese ability in this breed, and the logarithm of the ratio between the rennet clotting time and the curd firmness at 60 min (logRCT/A60) (0.65), which has been defined by other studies as an indicator trait of milk coagulation efficiency. This study represents a first step toward the possible use of the phenotype imputation of cheese-making traits to develop a practical methodology for the dairy sheep industry to impute cheese-making traits only based on the analysis of a milk sample without the need of pedigree information. This information could be also used in future planning of specific breeding programs considering the importance of the cheese-making efficiency in dairy sheep and highlights the potential of phenotype imputation to leverage sample size on expensive, hard-to-measure phenotypes. 相似文献
85.
Érika A. Praxedes Luiza B. de Queiroz Neta Alana A. Borges Maria B. Silva Maria V. O. Santos Leandro R. Ribeiro Herlon V. R. Silva Alexsandra F. Pereira 《Anatomia, histologia, embryologia》2020,49(1):121-129
Skin of mammals vulnerable to extinction, such as the jaguar, is used as a source of material in conservation strategies. The composition of skin is not uniform among species, and the ability to distinguish similarities in skin morphology in animal groups is fundamental in the application of skin tissue for use in biobanks. The aim of our study was to evaluate the structure, composition and capacity for culture of ear skin from the yellow and black jaguars. Both qualitative and quantitative methods were used, focusing on skin thickness, cell quantification and distribution, collagen density, proliferative activity and viability. Histomorphometrical study of the skin showed a total thickness of 273.2 and 274.6 µm for the yellow and black jaguars, respectively. Melanocytes and fibroblasts were, respectively, 9.7 and 23.0 for the yellow jaguar and 11.3 and 26.8 for the black jaguar. A collagen density of 67.0% and 49.0% was observed for yellow and black jaguars, respectively. Both animals presented a proliferative activity varying between 1.20 and 1.30. All tissues could promote cellular detachment, reaching subconfluence in 10–15 days. This kind of information from histomorphometrical features and cell cultures can be essential for a more targeted application of ear skin cryopreservation in this species, as such information will enable understanding the action of substances on tissues during the conservation process. 相似文献
86.
Beatriz Lozano-García Luis Parras-Alcántara 《Archives of Agronomy and Soil Science》2013,59(10):1429-1444
Understanding of tillage effects on soil chemical properties and cations in soil solution dynamics is essential for making appropriate land-management decisions. Measurements were made after more than 25 years of different tillage treatments: conventional tillage (CT) and conservation tillage, which includes no-till (NT) and minimum tillage (MT). pH and bulk density did not show important changes but exchangeable cations and cations in soil solution were affected by depth and different tillage. The highest concentration of exchangeable Ca2+ and Mg2+ was found in NT, decreased in MT and the lowest concentration was found in CT (mean values were 26.0, 24.4 and 23.3 cmolc kg?1 for exchangeable Ca2+ and 4.2, 3.7 and 3.3 cmolc kg?1 for exchangeable Mg2+ in NT, MT and CT, respectively). In addition, the highest concentration of exchangeable Na+ was found in NT, decreased in CT and the lowest concentration was found in MT. However, the highest concentration of exchangeable K+ was found in MT. A significant depth effect was observed for cations in soil solution: Na+ increased with depth whereas K+ and Ca2+ decreased with depth. This study aims to demonstrate the effect of tillage on the distribution and concentration of certain chemical soil properties. 相似文献
87.
88.
de Lima Marllos Santos Araujo Maristela Machado Berghetti Álvaro Luís Pasquetti Aimi Suelen Carpenedo Costella Claudia Griebeler Adriana Maria Somavilla Luiza Michelon dos Santos Osmarino Pires dos Reis Teixeira Valente Brígida Maria 《New Forests》2022,53(1):161-179
New Forests - The forestry sector has been able to sustainably satisfy the increasing global demand for forest products, thereby positively impacting the economy, while mitigating climate change.... 相似文献
89.
Patricio A. Díaz Beatriz Reguera Manuel Ruiz-Villarreal Yolanda Pazos Lourdes Velo-Suárez Henrick Berger Marc Sourisseau 《Marine drugs》2013,11(8):2964-2981
In 2012, there were exceptional blooms of D. acuminata in early spring in what appeared to be a mesoscale event affecting Western Iberia and the Bay of Biscay. The objective of this work was to identify common climatic patterns to explain the observed anomalies in two important aquaculture sites, the Galician Rías Baixas (NW Spain) and Arcachon Bay (SW France). Here, we examine climate variability through physical-biological couplings, Sea Surface Temperature (SST) anomalies and time of initiation of the upwelling season and its intensity over several decades. In 2012, the mesoscale features common to the two sites were positive anomalies in SST and unusual wind patterns. These led to an atypical predominance of upwelling in winter in the Galician Rías, and increased haline stratification associated with a southward advection of the Gironde plume in Arcachon Bay. Both scenarios promoted an early phytoplankton growth season and increased stability that enhanced D. acuminata growth. Therefore, a common climate anomaly caused exceptional blooms of D. acuminata in two distant regions through different triggering mechanisms. These results increase our capability to predict intense diarrhetic shellfish poisoning outbreaks in the early spring from observations in the preceding winter. 相似文献
90.