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101.
Le Moigne V Cariolet R Béven V Keranflec'h A Jestin A Dory D 《Research in veterinary science》2012,93(2):1032-1035
This study was performed to determine whether electroporation can be used to enhance the efficacy of a DNA vaccine against pseudorabies virus (PrV) in pigs. Immune responses to PrV were measured in pigs following a single intramuscular injection of plasmids encoding PrV glycoprotein B, with or without electroporation. Plasmid injection coupled with electroporation increased production of specific antibodies against PrV and peripheral blood mononuclear cells proliferated in response to stimulation with PrV glycoproteins. These results show that electroporation can improve the performance of a DNA vaccine against PrV in pigs. However, additional work is required to maximise the effectiveness of the vaccination protocol. 相似文献
102.
Thais Borges Lessa Rafael Cardoso Carvalho André Luis Rezende Franciolli Lilian Jesus de Oliveira RodrigoSilvadaNunes Barreto David Feder Fabiana Fernandes Bressan Maria Angélica Miglino Carlos Eduardo Ambrósio 《Acta veterinaria Scandinavica》2012,54(1):73
Background
The diaphragm is the major respiratory muscle affected by Duchenne muscular dystrophy (DMD) and is responsible for causing 80% of deaths. The use of mechanical forces that act on the body or intermittent pressure on the airways improves the quality of life of patients but does not prevent the progression of respiratory failure. Thus, diseases that require tissue repair, such as DMD, represent a group of pathologies that have great potential for cell therapy. The application of stem cells directly into the diaphragm instead of systemic application can reduce cell migration to other affected areas and increase the chances of muscle reorganisation. The mdx mouse is a suitable animal model for this research because its diaphragmatic phenotype is similar to human DMD. Therefore, the aim of this study was to assess the potential cell implantation in the diaphragm muscle after the xenotransplantation of stem cells.Methods
A total of 9 mice, including 3 control BALB/Cmice, 3 5-month-old mdx mice without stem cell injections and 3 mdx mice injected with stem cells, were used. The animals injected with stem cells underwent laparoscopy so that stem cells from GFP-labelled rabbit olfactory epithelium could be locally injected into the diaphragm muscle. After 8 days, all animals were euthanised, and the diaphragm muscle was dissected and subjected to histological and immunohistochemical analyses.Results
Both the fresh diaphragm tissue and immunohistochemical analyses showed immunopositive GFP labelling of some of the cells and immunonegativity of myoblast bundles. In the histological analysis, we observed a reduction in the inflammatory infiltrate as well as the presence of a few peripheral nuclei and myoblast bundles.Conclusion
We were able to implant stem cells into the diaphragm via local injection, which promoted moderate muscle reorganisation. The presence of myoblast bundles cannot be attributed to stem cell incorporation because there was no immunopositive labelling in this structure. It is believed that the formation of the bundles may have been stimulated by cellular signalling mechanisms that have not yet been elucidated. 相似文献103.
Eloisa Ortega-Vargas Silvia López-Ortiz Juan Andrés Burgueño-Ferreira W. Bruce Campbell Jesús Jarillo-Rodríguez 《Agroforestry Systems》2013,87(4):917-927
Guazuma ulmifolia was experimentally pruned to determine when pruning should begin during the rainy season in order to extend the production of green tree-forage during the dry season. Three prunings (P-1, P-2, and P-3) were performed (5 weeks apart) during the rainy season (August, September, and October) and four forage harvests (C-a, C-b, C-c, and C-d) (3 weeks apart) took place during the dry season (February, March, and April). Over 2 years, forage biomass production was evaluated as total biomass (g dry matter tree?1), biomass of the morphological components (leaves, stems, and dead matter), and nutritional quality (crude protein, fiber, lignin, and digestibility). Date of pruning affected the production of total biomass (P = 0.001) with the earliest pruning (P-1) yielding the greatest forage quantity, while stems (P = 0.022) and dead matter (P = 0.032) varied due to a year by pruning interaction. Total biomass, leaves, stems, and dead matter varied by the interaction between forage harvest and year for all four variables (P < 0.037). In both years, the largest forage harvest occurred in C-b (P < 0.05), leaf production was highest in C-a and C-b (P < 0.001), stem production was greatest in C-b (P = 0.013) and dead matter was highest in C-b and C-d (P = 0.002). Leaf crude protein ranged between 10 and 19 %, and the interaction of pruning by forage harvest by year was significant (P = 0.035). Digestibility, neutral and acid detergent fiber and lignin differed significantly because of the interaction between forage harvest and year (P < 0.005), with February showing the lowest values for fiber and the highest digestibility. The best time to prune G. ulmifolia is in August so that the young trees will produce more total biomass with a higher crude protein content. The most suitable moment for forage harvest is in February when the trees have more leaves with greater digestibility and less fiber. 相似文献
104.
Mónica Sebastiana Vanessa Tolentino Pereira André Alcântara Maria Salomé Pais Anabela Bernardes Silva 《New Forests》2013,44(6):937-949
Mediterranean ecosystems are characterized by large arid areas where the patchy distribution of trees offers little protection against harsh climate conditions for seedling establishment. Climate change is predicted to result in an increase in these arid regions, with pronounced effects on vegetation. Production of seedlings with developed ectomycorrhizas is a promising strategy for minimizing the initial transplant shock, thereby increasing plant survival and growth during the first, most critical years of a plantation. One important species in the Mediterranean basin is Quercus suber (cork oak), which occurs, together with other evergreen oak species, in an agro-silvo-pastoral system that represents an example of sustainable land use in Europe. In this study, a Pisolithus tinctorius isolate was used for ectomycorrhizal colonization of cork oak nursery seedlings, and the effects on aboveground plant growth and leaf structural and physiological parameters were investigated. Ectomycorrhizal development resulted in a significant increase in leaf area, dry weight, nitrogen content, and photosynthetic pigments, and mycorrhizal plants showed a higher photosynthetic capacity and water use efficiency. Nursery-inoculated plants established in the field showed increased survival and growth during the first year after transplant. These results indicate a potential for further enhancing the use of mycorrhizal inoculation as a cultivation practice in forest nurseries. Considering the difficulty of soil restoration under limiting environmental conditions, nursery inoculation with ectomycorrhizal fungi can be an important advantage for improving the quality of seedling stock and its performance after out-planting in the field, benefiting the regeneration of arid regions and the reintroduction of inocula of ectomycorrhizal fungi into these areas. 相似文献
105.
106.
Elena M. Balboa Sandra Rivas Andrés Moure Herminia Domínguez Juan Carlos Parajó 《Marine drugs》2013,11(11):4612-4627
The biomass components of the invasive seaweed Sargassum muticum were fractionated to allow their separate valorization. S. muticum (Sm) and the solid residue remaining after alginate extraction of this seaweed (AESm) were processed with hot, compressed water (hydrothermal processing) to assess the effects of temperature on fucoidan solubilization. Fucose-containing oligosaccharides were identified as reaction products. Operating under optimal conditions (170 °C), up to 62 and 85 wt% of the dry mass of Sm and AESm were solubilized, respectively. The reaction media were subjected to precipitation, nanofiltration and freeze-drying. The dried products contained 50% and 85% of the fucoidan present in Sm and AESm, respectively; together with other components such as phenolics and inorganic components. The saccharidic fraction, accounting for up to 35% of the dried extracts, contained fucose as the main sugar, and also galactose, xylose, glucose and mannose. The concentrates were characterized for antioxidant activity using the TEAC assay. 相似文献
107.
Colaço André F. Molin José P. Rosell-Polo Joan R. Escolà Alexandre 《Precision Agriculture》2019,20(4):805-822
Precision Agriculture - Site-specific management strategies are usually dependant on the understanding of the underlying cause and effect relationships that occur at the within-field level. The... 相似文献
108.
AbstractThe insecticidal efficacy of microwave irradiation against the at 12, 24, 48 and 72?h following exposure to microwave irradiations (100, 300?W) and the progeny production was assessed 45?days later. Linearly increasing irradiation power range (100, 200 and 300?W) was set up for determining mortality tendency. An increase of insect mortality caused by higher irradiation period and times elapsed after treatment has become evident commencing from 12?h after the treatment, which has significantly decreased at later elapsed time after treatment. The irradiation periods inducing the highest mortality at the examined powers were at 10?min and at 100?W power (72?h: 64.93%) and at 4.5?min. and at 300?W power (12?h: 87.01). In addition, a complete suppression of progeny production was achieved by 4.5?min treatment at 300?W power. Lognormal-type mortality process was caused by the linearly increased irradiation range. The properly chosen microwave irradiation can be used for management of Sitophilus granarius larval and adult developmental stages. This treatment could provide an effective and friendly environmental treatment technique in Integrated Pest Management (IPM) program. 相似文献
109.
Shiilegdamba E Carpenter TE Perez AM Thurmond MC 《Veterinary research communications》2008,32(3):201-207
Prior to 2000, foot-and-mouth disease (FMD) had not been observed in Mongolia since 1973; however, between April 2000 and
July 2002, Mongolia reported 44 FMD outbreaks that affected cattle, sheep, goats, and camels. The objectives of this study
were to describe the distributions of the 44 reported FMD outbreaks in Mongolia and to assess their spatial clustering and
directions of movement. Official reports were collected to obtain the number and species of animals both affected and at risk,
and the date and geographical coordinates of each outbreak. Significant global and local spatial clusters of reported FMD
outbreaks were identified. Disease spread during the second epidemic moved 76° northeast and the spread of the disease during
the third epidemic moved 110° northwest. FMD outbreaks were clustered intensely close to other FMD-positive counties. These
findings can be used in the future to help plan prevention and control measures in high risk areas. 相似文献
110.
Cardoso Daniel Barros Véras Robson Magno Liberal de Carvalho Francisco Fernando Ramos Magalhães André Luiz Rodrigues de Vasconcelos Gustavo Araújo Maciel Maria Inês Sucupira Madruga Marta Suely Urbano Stela Antas de Lima Silva Janaina 《Tropical animal health and production》2019,51(6):1515-1521
Tropical Animal Health and Production - The objective of this study was to evaluate the effect of the replacement of corn by cassava dregs (0, 33, 66, and 100%) in the diet of lamb on... 相似文献