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81.
82.
Chiara Beltramo Nadia Valentini Ezio Portis Daniela Torello Marinoni Paolo Boccacci Maria Angelica Sandoval Prando Roberto Botta 《Molecular breeding : new strategies in plant improvement》2016,36(3):27
The European hazelnut (Corylus avellana L.) is the most economically important nut species in the Betulaceae family. Despite the need for new improved hazelnut cultivars, few breeding programs are carried out because of the large plant size, the long lifecycle of the plant, and the expense and time required. To date, there are no reports of maps with quantitative trait loci (QTL) in hazelnut. Our objective in the present study was to identify QTL associated with vegetative traits to allow marker-assisted selection (MAS). An F1 progeny (275 plants) of Tonda Gentile delle Langhe × Merveille de Bollwiller obtained in 2009 was used to develop a QTL linkage map for vigour, sucker habit, and time of bud burst, after three years of observations. A set of 163 plants were analysed with 152 microsatellite markers. A map of 11 linkage groups was obtained, covering 663.1 cM, and 15 QTLs were identified and mapped for the traits examined. Of them, 10 were ‘major’ QTL, including a stably expressed region on LG_02 for leaf bud burst. At least one major QTL for each year underlies the variation in each trait and a clustering of QTL for trunk circumference and suckers/trunk circumference ratio with high inter-trait correlations was observed on LG_05, suggesting a single pleiotropic locus. This research represents an initial step in the future identification of chromosomal regions carrying genes of interest, important for breeding programs and MAS. 相似文献
83.
Thaís C. Lima Rodrigo Lucarini Angelica C. Volpe Carolina Q.J. de Andrade Alice M.P. Souza Patricia M. Pauletti Ana H. Januário Guilherme V. Símaro Jairo K. Bastos Wilson R. Cunha Alexandre Borges Rosangela da Silva Laurentiz Valéria A. Conforti Renato L.T. Parreira Carly H.G. Borges Giovanni F. Caramori Karla F. Andriani Márcio L.A. e Silva 《Bioorganic & medicinal chemistry letters》2017,27(2):176-179
(?)-Cubebin (CUB), isolated from seeds of Piper cubeba, was used as starting material to obtain the derivatives (?)-hinokinin (HK) and (?)-O-benzyl cubebin (OBZ). Using paw edema as the experimental model and different chemical mediators (prostaglandin and dextran), it was observed that both derivatives were active in comparison with both negative (5% Tween® 80 in saline) and positive (indomethacin) controls. The highest reduction in the prostaglandin-induced edema was achieved by OBZ (66.0%), while HK caused a 59.2% reduction. Nonetheless, the dextran-induced paw edema was not significantly reduced by either of the derivatives (HK or OBZ), which inhibited edema formation by 18.3% and 3.5%, respectively, in contrast with the positive control, cyproheptadine, which reduced the edema by 56.0%. The docking analysis showed that OBZ presented the most stable ligand-receptor (COX-2 – cyclooxygenase-2) interaction in comparison with CUB and HK. 相似文献
84.
85.
Crottini A Marotta R Barbuto M Casiraghi M Ferraguti M 《Molecular phylogenetics and evolution》2008,48(3):1189-1203
Tubifex tubifex Müller, 1774 is a cosmopolitan freshwater tubificid widely used as a model in ecotoxicology, population dynamics and developmental biology. It is traditionally recognized as a polytypic species and in Lambro River (Milano, Northern Italy) it occurs in two of the three recognized forms, named "tubifex" and "blanchardi", alternatively considered as ecological forms or distinct species. To investigate the genetic differentiation of the populations occurring in the Lambro River we sequenced a fragment of the 16S rDNA mitochondrial gene. T. blanchardi, characterized by a low genetic diversity, was genetically segregated from the other sympatric T. tubifex. The ancestral state reconstruction was used to define the morphological traits that support its distinctness. On the contrary, the other T. tubifex from the Lambro community, although morphologically indistinguishable, revealed an astonishing degree of genetic variability, both between and within the three identified clades that proved to be genetically isolated. Using samples from the mixed Lambro River community and from other countries around the world we present an overview of the species complex' 16S rDNA variability. Our results show that the genetic variability did not sensibly increase widening the data set, suggesting that the Lambro River populations meet the species' worldwide genetic variability. 相似文献
86.
The non-indigenous perennial grass, Arundo donax, is an aggressive invader of riparian areas throughout California and many sub-tropical regions of the world, and is hypothesized to provide poorer quality habitat for native wildlife in riparian systems. We sampled aerial and ground-dwelling insects and other terrestrial arthropods associated with Arundo, native willow vegetation (Salix spp.), and mixtures of the two vegetation types during two seasons to determine how Arundo influences invertebrate composition in a low gradient stream in central California. The total number of organisms, total biomass and taxonomic richness of aerial invertebrates associated with native vegetation was approximately twice that associated with Arundo vegetation, while mixed vegetation supported intermediate arthropod levels. Shannon-Weaver (Weiner) diversity associated with native vegetation stands was also higher than that of Arundo vegetation. Ground-dwelling assemblages did not show differences as great as aerial assemblages which are more critical to foraging avian species. These results indicate that vegetation type is a significant factor reducing the abundance and diversity of invertebrates in this, and presumably in many other riparian ecosystems where this invasive species has become a dominant component. Arundo invasion changes the vegetation structure of riparian zones and in turn, may increasingly jeopardize its habitat value for birds and other wildlife whose diets are largely composed of insects found in native riparian vegetation. 相似文献
87.
Angelica Crottini Janina Dordel Jrn Khler Frank Glaw Andreas Schmitz Miguel Vences 《Molecular phylogenetics and evolution》2009,53(1):345-350
A phylogeny for 29 species of scincine lizards from Madagascar, based on 3693 bp of six mitochondrial and five nuclear genes, revealed multiple parallel evolution of adaptations for a burrowing life, and unexpected relationships of the monotypic genera Androngo and Cryptoscincus. Androngo trivittatus was sister to Pygomeles braconnieri, and Cryptoscincus minimus was deeply nested within the genus Paracontias, all of these being fossorial taxa of elongated bodies and partly or fully reduced limbs. To account for these results, we place Cryptoscincus as a junior synonym of Paracontias, and discuss possible taxonomic consequences that may affect the status of Androngo, once additional data become available. 相似文献
88.
Ryan Tewhey Masakazu Nakano Xiaoyun Wang Carlos Pabón-Peña Barbara Novak Angelica Giuffre Eric Lin Scott Happe Doug N Roberts Emily M LeProust Eric J Topol Olivier Harismendy Kelly A Frazer 《Genome biology》2009,10(10):1-13
Background
Genome sequences, now available for most pathogens, hold promise for the rational design of new therapies. However, biological resources for genome-scale identification of gene function (notably genes involved in pathogenesis) and/or genes essential for cell viability, which are necessary to achieve this goal, are often sorely lacking. This holds true for Neisseria meningitidis, one of the most feared human bacterial pathogens that causes meningitis and septicemia.Results
By determining and manually annotating the complete genome sequence of a serogroup C clinical isolate of N. meningitidis (strain 8013) and assembling a library of defined mutants in up to 60% of its non-essential genes, we have created NeMeSys, a biological resource for Neisseria meningitidis systematic functional analysis. To further enhance the versatility of this toolbox, we have manually (re)annotated eight publicly available Neisseria genome sequences and stored all these data in a publicly accessible online database. The potential of NeMeSys for narrowing the gap between sequence and function is illustrated in several ways, notably by performing a functional genomics analysis of the biogenesis of type IV pili, one of the most widespread virulence factors in bacteria, and by identifying through comparative genomics a complete biochemical pathway (for sulfur metabolism) that may potentially be important for nasopharyngeal colonization.Conclusions
By improving our capacity to understand gene function in an important human pathogen, NeMeSys is expected to contribute to the ongoing efforts aimed at understanding a prokaryotic cell comprehensively and eventually to the design of new therapies. 相似文献89.
Claudia Kanashiro Tatiana C Santos Angelica Maria Miglino Andrea M Mess Anthony M Carter 《Reproductive biology and endocrinology : RB&E》2009,7(1):57-13
Background
The guinea pig is an attractive model for human pregnancy and placentation, mainly because of its haemomonochorial placental type, but is rather small in size. Therefore, to better understand the impact of body mass, we studied placental development in the capybara which has a body mass around 50 kg and a gestation period of around 150 days. We paid attention to the development of the lobulated arrangement of the placenta, the growth of the labyrinth in the course of gestation, the differentiation of the subplacenta, and the pattern of invasion by extraplacental trophoblast. 相似文献90.
Martin Montes Cesar Sanchez Kristien Verdonck Jordan E. Lake Elsa Gonzalez Giovanni Lopez Angelica Terashima Thomas Nolan Dorothy E. Lewis Eduardo Gotuzzo A. Clinton White Jr 《PLoS neglected tropical diseases》2009,3(6)