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排序方式: 共有481条查询结果,搜索用时 15 毫秒
11.
Jaqueline Raymondi Silva Larissa Campos de Medeiros Vinícius Pinho dos Reis Juliana Helena Chávez Thiago Demarchi Munhoz Gustavo Puia Borges Otavio Augusto Brioschi Soares Carlos Henrique Coelho de Campos Rosangela Zacarias Machado Cristiane Divan Baldani Maria Luana Cristiny Rodrigues Silva Joice Lara Maia Faria Edson Elias da Silva Luiz Tadeu Moraes Figueiredo 《Memórias do Instituto Oswaldo Cruz》2013,108(7):921-923
Since the emergence of West Nile virus (WNV) in North America in 1999, there have been several reports of WNV activity in Central and South American countries. To detect WNV in Brazil, we performed a serological survey of horses from different regions of Brazil using recombinant peptides from domain III of WNV. Positive samples were validated with the neutralisation test. Our results showed that of 79 ELISA-positive horses, nine expressed WNV-specific neutralising antibodies. Eight of the infected horses were from the state of Mato Grosso do Sul and one was from the state of Paraíba. Our results provide additional evidence for the emergence of WNV in Brazil and for its circulation in multiple regions of the country. 相似文献
12.
Luigi Piero Stasi Roberto Artusi Clara Bovino Benedetta Buzzi Luca Canciani Gianfranco Caselli Fabrizio Colace Paolo Garofalo Silvia Giambuzzi Patrice Larger Ornella Letari Stefano Mandelli Lorenzo Perugini Sabrina Pucci Matteo Salvi PierLuigi Toro 《Bioorganic & medicinal chemistry letters》2013,23(9):2653-2658
Starting from a orexin 1 receptor selective antagonist 4,4-disubstituted piperidine series a novel potent 5-azaspiro[2.4]heptane dual orexin 1 and orexin 2 receptor antagonist class has been discovered. SAR and Pharmacokinetic optimization of this series is herein disclosed. Lead compound 15 exhibits potent activity against orexin 1 and orexin 2 receptors along with low cytochrome P450 inhibition potential, good brain penetration and oral bioavailability in rats. 相似文献
13.
Danielly Beraldo dos Santos Silva Luana Mireli Carbonera Rodrigues Adriana Araújo de Almeida Kelly Mari Pires de Oliveira Alexéia Barufatti Grisolia/ 《Memórias do Instituto Oswaldo Cruz》2016,111(3):192-199
The azoles are the class of medications most commonly used to fight infections caused
by Candida sp. Typically, resistance can be attributed to mutations
in ERG11 gene (CYP51) which encodes the cytochrome P450
14α-demethylase, the primary target for the activity of azoles. The objective of this
study was to identify mutations in the coding region of theERG11
gene in clinical isolates of Candidaspecies known to be resistant to
azoles. We identified three new synonymous mutations in the ERG11
gene in the isolates of Candida glabrata (C108G, C423T and A1581G)
and two new nonsynonymous mutations in the isolates of Candida
krusei - A497C (Y166S) and G1570A (G524R). The functional consequence of
these nonsynonymous mutations was predicted using evolutionary conservation scores.
The G524R mutation did not have effect on 14α-demethylase functionality, while the
Y166S mutation was found to affect the enzyme. This observation suggests a possible
link between the mutation and dose-dependent sensitivity to voriconazole in the
clinical isolate of C. krusei. Although the presence of the Y166S in
phenotype of reduced azole sensitivity observed in isolate C.
kruseidemands investigation, it might contribute to the search of new
therapeutic agents against resistant Candida isolates. 相似文献
14.
Territory Availability at Different Spatial Scales does not Affect Fighting Investment in Males of the Lycaenid Butterfly Strymon mulucha
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Cibele P. S. Ferreira Luana P. Cerqueira Alexandre Uezu Eddy J. F. Oliveira Paulo E. C. Peixoto 《Ethology : formerly Zeitschrift fur Tierpsychologie》2016,122(10):798-806
In territorial species, rivals investment in fights over territories may increase when the availability of suitable areas for defense is low. This should occur because low territory availability may increase the costs to maintain and acquire territories. Although such process occurs in small spatial scales (local scale), territory availability in larger scales (regional scale) may also affect fighting investment, as losers should incur additional dispersing costs to find new territories. In this study, we used males of the hilltopping butterfly Strymon mulucha to evaluate the hypothesis that males should invest more in territorial fights when the costs to find new territories are higher (both at local and at regional scale). We timed male–male contests for territories located in 12 hilltops and measured male density per territory in each hilltop (local scale). We also quantified the distance between hilltops containing suitable areas for territories (regional scale). Male–male contests lasted 21 s on average, and copulations did not occur during the observations. The duration of contests was unrelated to the male density per territory or to the distance among hilltops, indicating that the investment in fights was unaffected by the availability of territorial sites, independent of the spatial scale. As male–male contests in S. mulucha are longer than the mean contest duration in other butterfly species and mating is extremely rare, we suggest that the value of each territory may be high enough to favor males that always invest as much as possible in contests. 相似文献
15.
Vera Lucia Portal Melissa Medeiros Markoski Alexandre Schaan de Quadros Sílvia Garofallo Julia Lorenzon dos Santos Aline Oliveira Camila Wechenfelder Viviane Paiva de Campos Priscilla Azambuja Lopes de Souza Luana Machado Aline Marcadenti 《Trials》2016,17(1)
BackgroundCardiovascular disease has become a major health problem, and it has been associated with both environmental and genetic factors. Studies have shown that the Mediterranean Diet (MeDiet), or its components such as nuts and olive oil, may be strongly associated with the improvement of cardiovascular risk factors in specific populations. The purpose of the GENUTRI study is to investigate the interaction of genetics with cardiovascular risk factors in a non-Mediterranean population with coronary artery disease (CAD) according to three different diets: rich in pecan nuts, in extra-virgin olive oil or a control diet.Methods/designThe GENUTRI study is a single-center, randomized, open-label, parallel-group, 12-week pragmatic clinical trial conducted in patients aged 40 to 80 years and diagnosed with CAD. A standardized questionnaire will be applied to data collection and a blood sample will be obtained for lipid, glycemic and inflammatory profile evaluation. Polymorphisms in the CD36 and STAT3 genes will be detected using the TaqMan® SNP Genotyping Assay. Patients will be allocated in three groups: group 1: 30 g/day of pecan nuts; group 2: 30 ml/day of olive oil; and group 3: control diet. The primary outcome will consist of changes in LDL-cholesterol (in mg/dl) after 12 weeks of intervention.DiscussionStudies have shown the beneficial effects of diets rich in nuts and olive oil mainly in the Mediterranean population. GENUTRI is a clinical trial focusing on the effects of nuts or olive oil supplementation in Brazilian individuals. Additionally, we will try to demonstrate that genetic polymorphisms linked to cardiovascular disease may modulate the effects of different diets on biochemical and inflammatory markers among these subjects.
Trial registration
ClinicalTrials.gov Identifier: (registered on 18 July 2014: first version). NCT02202265相似文献16.
17.
Luísa Czamanski Nora Cauã Antunes Westmann Leonardo Martins-Santana Luana de Fátima Alves Lummy Maria Oliveira Monteiro María-Eugenia Guazzaroni Rafael Silva-Rocha 《Microbial biotechnology》2019,12(1):125-147
When recombinant DNA technology was developed more than 40 years ago, no one could have imagined the impact it would have on both society and the scientific community. In the field of genetic engineering, the most important tool developed was the plasmid vector. This technology has been continuously expanding and undergoing adaptations. Here, we provide a detailed view following the evolution of vectors built throughout the years destined to study microorganisms and their peculiarities, including those whose genomes can only be revealed through metagenomics. We remark how synthetic biology became a turning point in designing these genetic tools to create meaningful innovations. We have placed special focus on the tools for engineering bacteria and fungi (both yeast and filamentous fungi) and those available to construct metagenomic libraries. Based on this overview, future goals would include the development of modular vectors bearing standardized parts and orthogonally designed circuits, a task not fully addressed thus far. Finally, we present some challenges that should be overcome to enable the next generation of vector design and ways to address it. 相似文献
18.
19.
Filippo Maggi Claudia Giuliani Gelsomina Fico Massimo Ricciutelli Massimo Bramucci Luana Quassinti 《Plant biosystems》2019,153(2):325-335
Apium nodiflorum (L.) Lag. (water celery) is an hydrophytic plant forming dense submerged populations occurring along streams and rivers of Europe. In the present work we provided new insights into the phytochemistry and biology of A. nodiflorum. In particular, we studied the chemical profile of essential oil and polar extracts obtained from the flowering aerial parts of water celery growing in central Italy, together with the essential oil biological activities, namely antimicrobial, antioxidant and cytotoxicity on tumour cells. In addition, we correlated the productivity in secondary metabolites to the secreting structures through a detailed micromorphological study. The essential oil was dominated by two main chemotypes, characterized by myristicin and limonene, respectively. The oils showed significant toxicity on tumour cells, as evidenced by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, with IC50 values in the range 3.8–15.9 μg mL?1, together with inhibitory effects on Candida albicans (inhibition zones of 10–11 mm). HPLC-MS analysis showed the caffeoylquinic acids and quercetin-3-O-glucoside as the most abundant phenolic compounds. Ducts and vittae were the principal secretory structures of vegetative (leaves and stems) and reproductive (fruits) parts, respectively, storing mainly essential oil. Results of this work provide scientific evidences for the possible valorization and exploitation of water celery. 相似文献