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81.
Vincenzo Giannini Rogelio Rodríguez-Oliveros Jose A. Sánchez-Gil 《Plasmonics (Norwell, Mass.)》2010,5(1):99-104
We investigate theoretically the optical properties associated to plasmon resonances of metal nanowires with cross section
given by low-order Chebyshev nanoparticles (like rounded-tip nanostars or nanoflowers). The impact of the nanoflower shape
is analyzed for varying symmetry and deformation parameter through the spectral dependence of resonances and their corresponding
near field distributions. Large field intensity enhancements are obtained at the gaps between petals, apart from the tips
themselves, which make these nanostars/nanoflowers specially suitable to host molecules for surface-enhanced Raman scattering
sensing applications. 相似文献
82.
Rogelio Zamilpa Elizabeth F. Lopez Ying Ann Chiao Qiuxia Dai Gladys P. Escobar Kevin Hakala Susan T. Weintraub Merry L. Lindsey 《Proteomics》2010,10(11):2214-2223
Matrix metalloproteinase‐9 (MMP‐9) deletion has been shown to improve remodeling of the left ventricle post‐myocardial infarction (MI), but the mechanisms to explain this improvement have not been fully elucidated. MMP‐9 has a broad range of in vitro substrates, but relevant in vivo substrates are incompletely defined. Accordingly, we evaluated the infarct regions of wild‐type (wt) and MMP‐9 null (null) mice using a proteomic strategy. Wt and null groups showed similar infarct sizes (48±3 in wt and 45±3% in null), indicating that both groups received an equal injury stimulus. Left ventricle infarct tissue was homogenized and analyzed by 2‐DE and MS. Of 31 spot intensity differences, the intensities of 9 spots were higher and 22 spots were lower in null mice compared to wt (all p<0.05). Several extracellular matrix proteins were identified in these spots by MS, including fibronectin, tenascin‐C, thrombospondin‐1, and laminin. Fibronectin was observed on the gels at a lower than expected molecular weight in the wt group, which suggested substrate cleavage, and the lower molecular weight spot was observed at lower intensity in the MMP‐9 null group, which suggested cleavage by MMP‐9. Immunoblotting confirmed the presence of fibronectin cleavage products in the wt samples and lower levels in the absence of MMP‐9. In conclusion, examining infarct tissue from wt and MMP‐9 null mice by proteomic analysis provides a powerful and unique method to identify in vivo candidate MMP substrates. 相似文献
83.
84.
Liliana I. Cichón Jimena Soleño Silvina A. Garrido Natalia Guiñazú Cristina M. Montagna Pierre Franck Jerome Olivares Selim Musleh Marcela A. Rodríguez Eduardo Fuentes-Contreras 《Journal of Applied Entomology》2021,145(9):911-921
The codling moth (Cydia pomonella (L.)) is an invasive pest of pome fruits introduced to the Americas in the 19–20th centuries. This pest is widespread on both sides of the Andes range separating Argentina and Chile. We performed an analysis of the population genetic variability and structure of C. pomonella in Argentina and Chile using 13 microsatellite markers and sampled C. pomonella from apple as the main host plant along its distribution area (approx. 1,800 km). A total of 22 locations (11 from Chile and 11 from Argentina) were sampled. Significant genetic differentiation was observed among samples from Argentina and Chile (FSC = 0.045) and between all localities (FST = 0.085). Significant isolation by distance (IBD) was found for each country and when samples from both sides of the Andes range were pooled, although a lower correlation coefficient was observed. The Mantel test showed that the geographic distance and highest altitude of the mountains between locations were significantly associated with the pairwise FST when samples from both sides of the Andes range were pooled. According to a Bayesian assignment test (STRUCTURE), samples from Argentina and Chile conformed to two distinct genetic clusters. Our results also suggest that the recent invasion of C. pomonella in the southernmost localities (Aysén Region in Chile and Santa Cruz Province in Argentina) originated in populations from the respective sides of the Andes range. Our results indicate a genetic exchange of C. pomonella within each country and significant genetic differentiation between countries, which could be explained by dispersal mediated by human activities related to fruit production within each country with little exchange between them. A possible explanation is that the Andes range could be a significant barrier for dispersal by flight, and quarantine barriers could prevent the movement of plant material or infested fruit between countries. 相似文献
85.
Ricardo Moreira Borges Fernanda das Neves Costa Fernanda O. Chagas Andrew Magno Teixeira Jaewon Yoon Márcio Barczyszyn Weiss Camila Manoel Crnkovic Alan Cesar Pilon Bruno C. Garrido Luz Adriana Betancur Abel M. Forero Leonardo Castellanos Freddy A. Ramos Mônica T. Pupo Stefan Kuhn 《Phytochemical analysis : PCA》2023,34(1):48-55
86.
87.
Dumas Gálvez Milagro Garrido Fermín Gil Hermógenes Fernández-Marín 《Entomologia Experimentalis et Applicata》2020,168(4):280-285
The omnipresence of pathogens makes them a strong selective pressure for most organisms, generating a variety of defensive responses to fight them. One mechanism by which organisms can release this pressure is avoidance of the pathogens in a spatial or temporal context. To date, only a few biological systems provide evidence that habitat selection can favour an escape from pathogens. An abiotic factor that varies across habitats and influences the evolution of host life history is humidity, which correlates positively with pathogen levels in the environment. Entomopathogenic fungi are abundant in soils and are obligate killers that require humidity for host infection. Antlions (Neuroptera: Myrmeleontidae) are typical soil-dwelling insects that can live several years as larvae, buried in dry and fine substrates where they build their traps. This lifestyle may release them from selective pressure by entomopathogenic fungi. Here, we investigated whether living underground provides protection against the generalist entomopathogenic fungus Beauveria bassiana (Bals.-Criv.) Vuill. in the antlion Myrmeleon timidus Gerstaecker under low or high humidity in the environment. Individuals that were inoculated with the fungus showed greater survival rates when buried in dry sand compared to individuals that were kept half-buried or without sand, with similar outcomes across humidity levels. Given that the diversity of antlions is higher in arid environments, this benefit obtained from pit-building behaviour seems to be a coincidental by-product of this foraging strategy, which would be particularly beneficial in environments where fungal pathogens are common. 相似文献
88.
89.
Hernando Jos Bolvar-Anillo Carlos Garrido Isidro G. Collado 《Phytochemistry Reviews》2020,19(3):721-740
Botrytis cinerea is the most widely studied necrotrophic phytopathogenic fungus. It causes economic losses that are difficult to calculate due to the large 相似文献
90.
Biofilms of As(III)-oxidising bacteria: formation and activity studies for bioremediation process development 总被引:1,自引:0,他引:1
Michel C Jean M Coulon S Dictor MC Delorme F Morin D Garrido F 《Applied microbiology and biotechnology》2007,77(2):457-467
The formation and activity of an As(III)-oxidising biofilm in a bioreactor, using pozzolana as bacterial growth support, was
studied for the purpose of optimising fixed-bed bioreactors for bioremediation. After 60 days of continuous functioning with
an As(III)-contaminated effluent, the active biofilm was found to be located mainly near the inflow rather than homogeneously
distributed. Biofilm development by the CAsO1 bacterial consortium and by Thiomonas arsenivorans was then studied both on polystyrene microplates and on pozzolana. Extra-cellular polymeric substances (EPS) and yeast extract
were found to enhance bacteria attachment, and yeast extract also appears to increase the kinetics of biofilm formation. Analysis
of proteins, sugars, lipids and uronic acids indicate that sugars were the main EPS components. The specific As(III)-oxidase
activity of T. arsenivorans was higher (by ninefold) for planktonic cells than for sessile ones and was induced by As(III). All the results suggest that
the biofilm structure is a physical barrier decreasing As(III) access to sessile cells and thus to As(III)-oxidase activity
induction. The efficiency of fixed-bed reactors for the bioremediation of arsenic-contaminated waters can be thus optimised
by controlling different factors such as temperature and EPS addition and/or synthesis to increase biofilm density and activity. 相似文献