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991.
Rodrigo Araújo Lima Rodrigues Ludmila Karen dos Santos Silva Fábio Pio Dornas Danilo Bretas de Oliveira Thais Furtado Ferreira Magalh?es Daniel Assis Santos Adriana Oliveira Costa Luiz de Macêdo Farias Paula Prazeres Magalh?es Cláudio Ant?nio Bonjardim Erna Geessien Kroon Bernard La Scola Juliana Reis Cortines J?natas Santos Abrah?o 《Journal of virology》2015,89(23):11812-11819
992.
Luiz Henrique Martins Fonseca Lúcia G. Lohmann 《Botanical journal of the Linnean Society. Linnean Society of London》2015,179(3):403-420
Little information on evolutionary relationships of Neotropical organisms or on the factors that have shaped the diversity currently encountered in this region is available. However, it is clear that biotic interactions and abiotic aspects have played important roles for species diversification in the region. This study focuses on Dolichandra (Bignonieae, Bignoniaceae), a clade of Neotropical lianas that is distributed broadly across different habitats and with diverse pollination and dispersal systems. We used sequences from two plastid DNA markers (ndhF and rpl32‐trnL) and one nuclear gene (PepC) to infer phylogenetic relationships in Dolichandra using parsimony and Bayesian approaches. We then used this phylogenetic framework as basis to study the biogeographic history, reconstruct the evolution of morphological characters and test the impact of morphology and environment on the diversification of the genus. More specifically, we: (1) time‐calibrate the phylogenetic tree of Dolichandra; (2) estimate the ancestral areas of the various lineages; (3) estimate the ancestral states of discrete and continuous morphological traits; (4) test for phylogenetic signal in environmental and phenotypic data; and (5) test whether morphological characters and/or niche evolution are correlated with cladogenesis. All Dolichandra spp. are monophyletic in the combined molecular phylogeny; relationships among species are generally well resolved, although poorly supported in some instances. The genus is inferred to have originated 36.43–26.23 Mya, possibly in eastern South America. Ancestral state reconstructions of continuous and discrete floral characters inferred a mixed morphology as the ancestral condition for the group. Phylogenetic signal differed between perianth and sexual whorls and gradual evolution was recovered for all traits except style length and anther length. Environmental variables showed no phylogenetic signal and a pattern of variation that was not correlated with branch length, suggesting that environmental transitions were concomitant with speciation. Dispersal is inferred to be the main driver of the differential distribution observed among species. In addition, climatic preferences and floral characters seem to have been important reproductive barriers in Dolichandra. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 403–420. 相似文献
993.
A Semiquantitative Scoring Tool to Evaluate Eccentric Exercise-Induced Muscle Damage in Trained Rats
D. Rizo-Roca J.G. Ríos-Kristjánsson C. Nú?ez-Espinosa A.A. Ascens?o J. Magalh?es J.R. Torrella T. Pagès G. Viscor 《European journal of histochemistry : EJH》2015,59(4)
Unaccustomed eccentric exercise is a well-documented cause of exercise-induced muscle damage. However, in trained subjects muscle injury involves only light or moderate tissue damage. Since trained rats are widely used as a model for skeletal muscle injury, here we propose a semiquantitative scoring tool to evaluate muscle damage in trained rats. Twenty male Sprague-Dawley rats were trained for two weeks following a two-week preconditioning period, and randomly divided into two groups: control rats (CTL; n=5) and rats with eccentric exercise-induced muscle damage (INJ; n=15). Injured rats were sacrificed at three time points: 1, 3 and 7 days post injury (n=5 each). Transverse sections from the right soleus were cut (10 µm) and stained with haematoxylin-eosin. Samples were evaluated by two groups of observers (four researchers experienced in skeletal muscle histopathology and four inexperienced) using the proposed tool, which consisted of six items organised in three domains: abnormal fibre morphology, necrotic/(re) degenerating fibres (muscle fibre domain), endomysial and perimysial infiltration (inflammatory state domain) and endomysium and perimysium distension (interstitial compartment domain). We observed the expected time course in the six evaluated items. Furthermore, agreement among observers was evaluated by measuring the Intraclass Correlation Coefficient (ICC). Within the experienced group, items from the muscle fibre and interstitial compartment domains showed good agreement and the two items from the infiltration compartment domain showed excellent agreement. In conclusion, the proposed tool allowed quick and correct evaluation of light to moderate muscle damage in trained rats with good agreement between observers.Key words: Histopathology, haematoxylin-eosin, histochemical method 相似文献
994.
995.
Guillermo Pardo Raúl Moral Eduardo Aguilera Agustín del Prado 《Global Change Biology》2015,21(3):1313-1327
The establishment of sustainable soil waste management practices implies minimizing their environmental losses associated with climate change (greenhouse gases: GHGs) and ecosystems acidification (ammonia: NH3). Although a number of management strategies for solid waste management have been investigated to quantify nitrogen (N) and carbon (C) losses in relation to varied environmental and operational conditions, their overall effect is still uncertain. In this context, we have analyzed the current scientific information through a systematic review. We quantified the response of GHG emissions, NH3 emissions, and total N losses to different solid waste management strategies (conventional solid storage, turned composting, forced aerated composting, covering, compaction, addition/substitution of bulking agents and the use of additives). Our study is based on a meta‐analysis of 50 research articles involving 304 observations. Our results indicated that improving the structure of the pile (waste or manure heap) via addition or substitution of certain bulking agents significantly reduced nitrous oxide (N2O) and methane (CH4) emissions by 53% and 71%, respectively. Turned composting systems, unlike forced aerated composted systems, showed potential for reducing GHGs (N2O: 50% and CH4: 71%). Bulking agents and both composting systems involved a certain degree of pollution swapping as they significantly promoted NH3 emissions by 35%, 54%, and 121% for bulking agents, turned and forced aerated composting, respectively. Strategies based on the restriction of O2 supply, such as covering or compaction, did not show significant effects on reducing GHGs but substantially decreased NH3 emissions by 61% and 54% for covering and compaction, respectively. The use of specific additives significantly reduced NH3 losses by 69%. Our meta‐analysis suggested that there is enough evidence to refine future Intergovernmental Panel on Climate Change (IPCC) methodologies from solid waste, especially for solid waste composting practices. More holistic and integrated approaches are therefore required to develop more sustainable solid waste management systems. 相似文献
996.
997.
Mariele Porto Carneiro Le?o Patricia Vieira Tiago Fernando Dini Andreote Welington Luiz de Araújo Neiva Tinti de Oliveira 《Genetics and molecular biology》2015,38(1):86-92
The entomopathogenic fungi of the genus Metarhizium have several
subtilisin-like proteases that are involved in pathogenesis and these have been used
to investigate genes that are differentially expressed in response to different
growth conditions. The identification and characterization of these proteases can
provide insight into how the fungus is capable of infecting a wide variety of insects
and adapt to different substrates. In addition, the pr1A gene has
been used for the genetic improvement of strains used in pest control. In this study
we used quantitative RT-PCR to assess the relative expression levels of the
pr1A gene in M. anisopliae and M.
acridum during growth in different culture conditions and during
infection of the sugar cane borer, Diatraea saccharalis Fabricius.
We also carried out a pathogenicity test to assess the virulence of both species
against D. saccharalis and correlated the results with the pattern
of pr1A gene expression. This analysis revealed that, in both
species, the pr1A gene was differentially expressed under the growth
conditions studied and during the pathogenic process. M. anisopliae
showed higher expression of pr1A in all conditions examined, when
compared to M. acridum. Furthermore, M. anisopliae
showed a greater potential to control D. saccharalis. Taken
together, our results suggest that these species have developed different strategies
to adapt to different growing conditions. 相似文献
998.
Density‐related effects on the infectivity and aggressiveness of a sterilising smut in a wild population of Digitaria sanguinalis
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Understanding host–pathogen evolutionary dynamics needs characterisation and quantification of processes occurring at many spatiotemporal scales. With this aim, the effects of smut on a naturally infected population of the summer annual Digitaria sanguinalis were followed for 4 years in an uncropped field. The main purpose of the study was to quantify the effects of within‐population density on the infectivity and the aggressiveness of the pathogen in a range of densities that occurred naturally. The infectivity‐related variable measured was the proportion of smutted plants at the end of each growing season; proportions were analysed using a generalised linear model with a binomial distribution considering the year, the density and their interaction as effects. The aggressiveness‐related variables chosen were the number of smutted inflorescences per plant and per area, obtained over the last 2 years; they were analysed by means of ancova considering disease status (seeded or smutted), year, density and all the interactions between them. Although the disease is monocyclic, results showed clearly that infectivity increased with plant density. The number of inflorescences per plant was 1.5 times higher in smutted plants than in healthy plants throughout the range of densities. This variable declined when density increased, but as the infectivity increased at a higher rate, the aggressiveness also increased with density. The surprising results on infectivity are discussed in the context of current knowledge of plant–pathogen interaction dynamics, as well as neighbour effects on pathogen aggressiveness. Moreover, the results could be useful to develop weed biological control strategies. 相似文献
999.
1000.
Marco Aurélio Soares Roberta Amália de Carvalho Araújo Marjorie Mendes Marini Luciana Márcia de Oliveira Leonardo Gomes de Lima Viviane de Souza Alves Maria Sueli Soares Felipe Marcelo Macedo Brigido Celia Maria de Almeida Soares Jose Franco da Silveira Jeronimo Concei??o Ruiz Patrícia Silva Cisalpino 《BMC genomics》2015,16(1)