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931.
932.
Romanyà Joan Sancho-Adamson Marc Ortega Daniela Trillas M. Isabel 《Plant and Soil》2019,436(1-2):193-209
Plant and Soil - Verticillium wilt, caused by the soil-borne pathogenic fungus Verticillium dahliae (Kleb), is one of the most severe diseases of olive trees in Mediterranean agriculture. At... 相似文献
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Alba Casellas Cristina Mallol Ariana Salavert Veronica Jimenez Miquel Garcia Judith Agudo Mercè Obach Virginia Haurigot Laia Vilà Maria Molas Ricardo Lage Meritxell Morró Estefania Casana Jesús Ruberte Fatima Bosch 《The Journal of biological chemistry》2015,290(27):16772-16785
The human insulin-like growth factor 2 (IGF2) and insulin genes are located within the same genomic region. Although human genomic studies have demonstrated associations between diabetes and the insulin/IGF2 locus or the IGF2 mRNA-binding protein 2 (IGF2BP2), the role of IGF2 in diabetes pathogenesis is not fully understood. We previously described that transgenic mice overexpressing IGF2 specifically in β-cells (Tg-IGF2) develop a pre-diabetic state. Here, we characterized the effects of IGF2 on β-cell functionality. Overexpression of IGF2 led to β-cell dedifferentiation and endoplasmic reticulum stress causing islet dysfunction in vivo. Both adenovirus-mediated overexpression of IGF2 and treatment of adult wild-type islets with recombinant IGF2 in vitro further confirmed the direct implication of IGF2 on β-cell dysfunction. Treatment of Tg-IGF2 mice with subdiabetogenic doses of streptozotocin or crossing these mice with a transgenic model of islet lymphocytic infiltration promoted the development of overt diabetes, suggesting that IGF2 makes islets more susceptible to β-cell damage and immune attack. These results indicate that increased local levels of IGF2 in pancreatic islets may predispose to the onset of diabetes. This study unravels an unprecedented role of IGF2 on β-cells function. 相似文献
937.
Karla Cameron-Veas Marc Solà-Ginés Miguel A. Moreno Lorenzo Fraile Lourdes Migura-Garcia 《Applied and environmental microbiology》2015,81(5):1782-1787
The aim of this study was to evaluate if the treatments with ceftiofur and amoxicillin are risk factors for the emergence of cephalosporin resistant (CR) E. coli in a pig farm during the rearing period. One hundred 7-day-old piglets were divided into two groups, a control (n = 50) group and a group parenterally treated with ceftiofur (n = 50). During the fattening period, both groups were subdivided in two. A second treatment with amoxicillin was administered in feed to two of the four groups, as follows: group 1 (untreated, n = 20), group 2 (treated with amoxicillin, n = 26), group 3 (treated with ceftiofur, n = 20), and group 4 (treated with ceftiofur and amoxicillin, n = 26). During treatment with ceftiofur, fecal samples were collected before treatment (day 0) and at days 2, 7, 14, 21, and 42 posttreatment, whereas with amoxicillin, the sampling was extended 73 days posttreatment. CR E. coli bacteria were selected on MacConkey agar with ceftriaxone (1 mg/liter). Pulsed-field gel electrophoresis (PFGE), MICs of 14 antimicrobials, the presence of cephalosporin resistance genes, and replicon typing of plasmids were analyzed. Both treatments generated an increase in the prevalence of CR E. coli, which was statistically significant in the treated groups. Resistance diminished after treatment. A total of 47 CR E. coli isolates were recovered during the study period; of these, 15 contained blaCTX-M-1, 10 contained blaCTX-M-14, 4 contained blaCTX-M-9, 2 contained blaCTX-M-15, and 5 contained blaSHV-12. The treatment with ceftiofur and amoxicillin was associated with the emergence of CR E. coli during the course of the treatment. However, by the time of finishing, CR E. coli bacteria were not recovered from the animals. 相似文献
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939.
Carolina Musso Heloísa S. Miranda Amadeu M. V. M. Soares Susana Loureiro 《Plant and Soil》2014,378(1-2):49-58
Aims
The Cerrado, a South American savanna, is considered a priority for conservation. In this case study, we assessed soil feeding activity as a way to improve understanding of the ecosystem functioning, in order to support and refine conservation strategies.Methods
Soil feeding activity was assessed using the bait-lamina method under different environmental conditions: in the dry and rainy seasons, in burned and unburned areas, and under native and invasive grasses.Results
Feeding activity was significantly reduced after fire, but recovered to pre-fire levels with the rains. Activity increased significantly during the rainy season in both areas, being more pronounced in the unburned area. The highest feeding activity was observed under the invasive grass (Melinis minutiflora). Feeding activity declined with soil depth and was affected by season and fire.Conclusions
Seasonality was the most important factor affecting the feeding activity of soil organisms, followed by the fire history and the extant vegetation. Although this method does not allow distinguishing between feeding activity of different organisms, it can provide valuable insights into differences in soil functioning due to changes in environmental conditions. 相似文献940.
C. Fonseca M. Caminal D. Peris J. Barrachina P. J. Fàbregas F. Garcia J. J. Cairó F. Gòdia A. Pla J. Vives 《Cytotechnology》2014,66(2):345-354
Osteochondral injuries are common in humans and are relatively difficult to manage with current treatment options. The combination of novel biomaterials and expanded progenitor or stem cells provides a source of therapeutic and immunologically compatible medicines that can be used in regenerative medicine. However, such new medicinal products need to be tested in translational animal models using the intended route of administration in humans and the intended delivery device. In this study, we evaluated the feasibility of an arthroscopic approach for the implantation of biocompatible copolymeric poly-d,l-lactide-co-glycolide (PLGA) scaffolds in an ovine preclinical model of knee osteochondral defects. Moreover this procedure was further tested using ex vivo expanded autologous chondrocytes derived from cartilaginous tissue, which were loaded in PLGA scaffolds and their potential to generate hyaline cartilage was evaluated. All scaffolds were successfully implanted arthroscopically and the clinical evolution of the animals was followed by non invasive MRI techniques, similar to the standard in human clinical practice. No clinical complications occurred after the transplantation procedures in any of the animals. Interestingly, the macroscopic evaluation demonstrated significant improvement after treatment with scaffolds loaded with cells compared to untreated controls. 相似文献