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541.
Selecting plant species for practical restoration of degraded lands using a multiple‐trait approach 下载免费PDF全文
Tereza C. Giannini Ana M. Giulietti Raymond M. Harley Pedro L. Viana Rodolfo Jaffe Ronnie Alves Carlos E. Pinto Nara F. O. Mota Cecílio F. Caldeira Jr Vera L. Imperatriz‐Fonseca Antonio E. Furtini Jose O. Siqueira 《Austral ecology》2017,42(5):510-521
Ecological restoration is essential in rehabilitating degraded areas and safeguarding biodiversity, ecosystem services and human welfare. Using functional traits to plan restoration strategies has been suggested as they are the main ecological attributes that underlie ecosystem processes and services. However, few studies have translated ecological theory into actual restoration practices that can be easily used by different stakeholders. In this article, we applied a multiple‐trait approach to select plant species for the restoration of degraded lands inside the Brazilian Amazon Forests. We selected 10 traits encompassing ease of management, geographical distribution and interactions with animals and other ecosystem services and scored these traits using 118 native species. Then, we ranked all species according to the total number of traits that they exhibited to obtain a list of 53 highly ranked species. In addition, we employed non‐metric multidimensional scaling (NMDS) to assess the variation in these traits across the entire group of species. Based on the results, we selected a subset of species that maximizes functional diversity (high variability). We performed a sparse linear discriminant analysis (SLDA) to highlight a minimum set of traits to effectively discriminate botanical families. The final list of species and their traits highlight the importance of preserving not only the historical reference of a focused ecosystem but also its functional diversity to restore the interaction with local fauna, enrich the food chain and guarantee ecosystem services for local communities. 相似文献
542.
Yzel R. Súarez Edileia A. Silva Lucilene F. Viana 《Environmental Biology of Fishes》2017,100(7):775-783
We studied the reproductive biology of Astyanax lacustris in the southern Pantanal, Brazil. A total of 382 fish were analyzed from February 2009 to January 2011. The sex ratio differed significantly from 1:1, with a larger proportion of females (χ2 = 27.24; p < 0.001). Females achieve higher standard length than males (mean 72.30 mm and 56.51 mm, respectively), and possess negative allometric growth while males have positive allometric growth. Size at first maturation did not differ between sexes. The greatest reproductive activity occurred during the rainy season, when temperatures were highest (November to February). Total fecundity was significantly correlated with standard length (rs = 0.74; p = 0.01), and spawn type was total. Then, the life history traits of A. lacustris are adjusted to seasonal variation in the Southern Pantanal. 相似文献
543.
T. Bacca E.R. Lima M.C. Picanço R.N.C. Guedes & J.H.M. Viana 《Entomologia Experimentalis et Applicata》2006,119(1):39-45
Pest monitoring with pheromone traps is affected mainly by factors such as trap placement and pest biology. The intertrap distance can affect the capture due to competition among traps that are placed at short distances. We studied the interference among pheromone traps used to monitor males of the coffee leaf miner, Leucoptera coffeella (Guérin‐Méneville) (Lepidoptera: Lyonetiidae), with traps placed at various distances. Using geostatistical analysis, we determined at what distance captures were independent from other traps. Traps were placed in groups of 12 with distances among traps per group either 2, 5, 10, 15, or 30 m. Traps were checked for males every 4 days during 16 days. We found interference between traps when intertrap distances were shorter than 10 m. The range and magnitude of spatial dependence varied considerably among each sampling date and wind direction. For directions of 45° and 135°, the traps should be placed 110 and 177 m apart, respectively, to obtain spatially independent counts and therefore representative samplings for assessing the insect population in the area. These results have implications for developing sampling plans for managing L. coffeella with pheromone traps; the spatial analysis indicated that a trap density of one pheromone trap for every 3.5–4 ha would be adequate for the monitoring of the coffee leaf miner. 相似文献
544.
- Monitoring introduction and spread of nonindigenous species via maritime transport and performing risk assessments require port biological baseline surveys. Yet, the comprehensiveness of these surveys is often compromised by the large number of habitats present in a port, the seasonal variability, and the time‐consuming morphological approach used for taxonomic identification. Metabarcoding represents a promising alternative for rapid comprehensive port biological baseline surveys, but its application in this context requires further assessments.
- We applied metabarcoding (based on barcodes of the cytochrome c oxidase subunit I and of the 18S ribosomal RNA gene) to 192 port samples collected (a) from diverse habitats (water column—including environmental DNA and zooplankton, sediment, and fouling structures), (b) at different sites (from inner to outer estuary), and iii) during the four seasons of the year.
- By comparing the biodiversity metrics derived from each sample group, we show that each sampling method resulted in a distinct community profile and that environmental DNA alone cannot substitute for organismal sampling, and that, although sampling at different seasons and locations resulted in higher observed biodiversity, operational results can be obtained by sampling selected locations and seasons.
- By assessing the taxonomic composition of the samples, we show that metabarcoding data allowed the detection of previously recorded nonindigenous species as well as to reveal presence of new ones, even if in low abundance.
- Synthesis and application. Our comprehensive assessment of metabarcoding for port biological baseline surveys sets the basics for cost‐effective, standardized, and comprehensive monitoring of nonindigenous species and for performing risk assessments in ports. This development will contribute to the implementation of the recently entered into force International Convention for the Control and Management of Ships' Ballast Water and Sediments.
545.
Dias Aline Marques de Mendonça Raíssa Pinheiro da Silva Kataoka Maria Sueli Jaeger Ruy G. de Jesus Viana Pinheiro João de Melo Alves Junior Sérgio 《Molecular biology reports》2022,49(5):3665-3674
Molecular Biology Reports - The invasive behaviour of squamous cell carcinoma (SCC), a common malignant tumour of the mouth, is a process mediated by cell proliferation, extracellular matrix... 相似文献
546.
Nathalie Boulet Anaïs Briot Valentin Jargaud David Estève Anne Rémaury Chloé Belles Pénélope Viana Jessica Fontaine Lucie Murphy Catherine Déon Marie Guillemot Catherine Pech Yaligara Veeranagouda Michel Didier Pauline Decaunes Etienne Mouisel Christian Carpéné Jason S. Iacovoni Alexia Zakaroff-Girard Jean-Louis Grolleau Jean Galitzky Séverine Ledoux Jean-Claude Guillemot Anne Bouloumié 《Aging cell》2023,22(3):e13776
547.
G S Viana K M Carvalho M G Gadelha 《Archives internationales de physiologie et de biochimie》1979,87(4):711-728
Cholinesterase activity was detected in the ascitic fluid of Ehrlich tumour and studied in a comparative manner in relation to that found in mice plasma. Enzymes from both sources were characterized with respect to optimum pH, substrate concentration and quinidine inhibition. After gel filtration by Sephadex G-200 and Sepharose 6B, two enzyme forms were observed in ascitic fluid as well as in mice plasma: a large form (L) and a small form (S) presenting molecular weights of 191 000, and 224 000 daltons for L forms and 71 000 and 69 000 daltons for S forms respectively. Concanavalin A interacts with both molecular forms, suggesting a glycoprotein nature for these enzymes. 相似文献
548.
Arancha Catalan-Moreno Marta Cela Pilar Menendez-Gil Naiara Irurzun Carlos
J Caballero Isabelle Caldelari Alejandro Toledo-Arana 《Nucleic acids research》2021,49(6):3409
Thermoregulation of virulence genes in bacterial pathogens is essential for environment-to-host transition. However, the mechanisms governing cold adaptation when outside the host remain poorly understood. Here, we found that the production of cold shock proteins CspB and CspC from Staphylococcus aureus is controlled by two paralogous RNA thermoswitches. Through in silico prediction, enzymatic probing and site-directed mutagenesis, we demonstrated that cspB and cspC 5′UTRs adopt alternative RNA structures that shift from one another upon temperature shifts. The open (O) conformation that facilitates mRNA translation is favoured at ambient temperatures (22°C). Conversely, the alternative locked (L) conformation, where the ribosome binding site (RBS) is sequestered in a double-stranded RNA structure, is folded at host-related temperatures (37°C). These structural rearrangements depend on a long RNA hairpin found in the O conformation that sequesters the anti-RBS sequence. Notably, the remaining S. aureus CSP, CspA, may interact with a UUUGUUU motif located in the loop of this long hairpin and favour the folding of the L conformation. This folding represses CspB and CspC production at 37°C. Simultaneous deletion of the cspB/cspC genes or their RNA thermoswitches significantly decreases S. aureus growth rate at ambient temperatures, highlighting the importance of CspB/CspC thermoregulation when S. aureus transitions from the host to the environment. 相似文献
549.
550.
Sara Flamini Philipp Sergeev Zenobio Viana de Barros Tommaso Mello Michele Biagioli Musetta Paglialunga Chiara Fiorucci Tatiana Prikazchikova Stefano Pagano Andrea Gagliardi Carlo Riccardi Timofei Zatsepin Graziella Migliorati Oxana Bereshchenko Stefano Bruscoli 《Cell death & disease》2021,12(5)
Liver fibrosis (LF) is a dangerous clinical condition with no available treatment. Inflammation plays a critical role in LF progression. Glucocorticoid-induced leucine zipper (GILZ, encoded in mice by the Tsc22d3 gene) mimics many of the anti-inflammatory effects of glucocorticoids, but its role in LF has not been directly addressed. Here, we found that GILZ deficiency in mice was associated with elevated CCL2 production and pro-inflammatory leukocyte infiltration at the early LF stage, resulting in enhanced LF development. RNA interference-mediated in vivo silencing of the CCL2 receptor CCR2 abolished the increased leukocyte recruitment and the associated hepatic stellate cell activation in the livers of GILZ knockout mice. To highlight the clinical relevance of these findings, we found that TSC22D3 mRNA expression was significantly downregulated and was inversely correlated with that of CCL2 in the liver samples of patients with LF. Altogether, these data demonstrate a protective role of GILZ in LF and uncover the mechanism, which can be targeted therapeutically. Therefore, modulating GILZ expression and its downstream targets represents a novel avenue for pharmacological intervention for treating LF and possibly other liver inflammatory disorders.Subject terms: Chronic inflammation, Experimental models of disease 相似文献