Supressão de plantas daninhas por leguminosas anuais em sistema agroecológico na Pré-Amazônia.

Este trabalho teve por objetivos identificar e avaliar a agressividade potencial das plantas daninhas em um agrossistema com leguminosas herbáceas anuais como cobertura de solo. Foram plantadas, nas ruas de um sistema de aléias de sombreiro ( Clitoria fairchildiana) e no final do período agrícola, as leguminosas mucuna-preta, feijão-guandu, feijão-de-porco e calopogônio, em sistema de blocos ao acaso com cinco repetições. Para estudo da dinâmica da composição florística, avaliaram-se a freqüência, densidade, dominância, similaridade, diversidade de espécies e biomassa das plantas daninhas. Foram identificadas 42 espécies de plantas espontâneas, das quais as mais freqüentes e de maior densidade e dominância foram Leptochoa virgata, Panicumlaxum e Sidasp. Não foram detectadas diferenças significativas para densidade, número de espécies, diversidade e biomassa entre as plantas daninhas emergidas nos quatro tratamentos com leguminosas; nem destas em relação ao controle

Biological evaluation of alginate-based hydrogels, with antimicrobial features by Ce(III) incorporation, as vehicles for a bone substitute

In this work three different hydrogels were developed to associate, as vehicles, with the synthetic bone substitute GR-HA. One based on an alginate matrix (Alg); a second on a mixture of alginate and chitosan (Alg/Ch); and a third on alginate and hyaluronate (Alg/HA), using Ca2+ ions as cross-linking agents. The hydrogels, as well as the respective injectable bone substitutes (IBSs), were fully characterized from the physical-chemical point of view. Weight change studies proved that all hydrogels were able to swell and degrade within 72 hours at pH 7.4 and 4.0, being Alg/HA the hydrogel with the highest degradation rate (80%). Rheology studies demonstrated that all hydrogels are non-Newtonian viscoelastic fluids, and injectability tests showed that IBSs presented low maximum extrusion forces, as well as quite stable average forces. In conclusion, the studied hydrogels present the necessary features to be successfully used as vehicles of GR-HA, particularly the hydrogel Alg/HA.The authors would like to acknowledge the financial support from FCT (Fundacao para a Ciencia e a Tecnologia) through the grant SFRH/BD/76237/2011 and project ENMED/0002/2010, from FEDER funds through the program COMPETE-Programa Operacional Factores de Competitividade-under the project PEst-C/EME/UI0285/2011, as well as to the project I&DT BIOMAT&CELL n. 1372

Recent updates and perspectives on approaches for the development of vaccines against visceral leishmaniasis

All rights reserved. Visceral leishmaniasis (VL) is one of the most important tropical diseases worldwide. Although chemotherapy has been widely used to treat this disease, problems related to the development of parasite resistance and side effects associated with the compounds used have been noted. Hence, alternative approaches for VL control are desirable. Some methods, such as vector control and culling of infected dogs, are insufficiently effective, with the latter not ethically recommended. The development of vaccines to prevent VL is a feasible and desirable measure for disease control, for example, some vaccines designed to protect dogs against VL have recently been brought to market. These vaccines are based on the combination of parasite fractions or recombinant proteins with adjuvants that are able to induce cellular immune responses, however, their partial efficacy and the absence of a vaccine to protect against human leishmaniasis underline the need for characterization of new vaccine candidates. This review presents recent advances in control measures for VL based on vaccine development, describing extensively studied antigens, as well as new antigenic proteins recently identified using immuno-proteomic techniquesThis work was supported by grants from Instituto Nacional de Ciência e Tecnologia em Nano-Biofarmacêutica, Rede Nanobiotec/Brasil-Universidade Federal de Uberlândia/CAPES, PRONEX-FAPEMIG (APQ-01019-09), FAPEMIG (CBB-APQ-00819-12 and CBB-APQ-01778-2014), and CNPq (APQ-482976/2012-8, APQ-488237/2013-0, and APQ-467640/2014-9). EAFC and LRG are recipients of the grant from CNPq. MACF is the recipient of grants from FAPEMIG/CAPE

Transiting exoplanets from the CoRoT space mission XVII. The hot Jupiter CoRoT-17b: a very old planet

We report on the discovery of a hot Jupiter-type exoplanet, CoRoT-17b, detected by the CoRoT satellite. It has a mass of $2.43\pm0.30$\Mjup and a radius of $1.02\pm0.07$\Rjup, while its mean density is $2.82\pm0.38$ g/cm$^3$. CoRoT-17b is in a circular orbit with a period of $3.7681\pm0.0003$ days. The host star is an old ($10.7\pm1.0$ Gyr) main-sequence star, which makes it an intriguing object for planetary evolution studies. The planet's internal composition is not well constrained and can range from pure H/He to one that can contain $\sim$380 earth masses of heavier elements.Comment: Published (A&A 531, A41, 2011

Spatio-Temporal Tracking and Phylodynamics of an Urban Dengue 3 Outbreak in São Paulo, Brazil

The dengue virus has a single-stranded positive-sense RNA genome of ∼10.700 nucleotides with a single open reading frame that encodes three structural (C, prM, and E) and seven nonstructural (NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5) proteins. It possesses four antigenically distinct serotypes (DENV 1–4). Many phylogenetic studies address particularities of the different serotypes using convenience samples that are not conducive to a spatio-temporal analysis in a single urban setting. We describe the pattern of spread of distinct lineages of DENV-3 circulating in São José do Rio Preto, Brazil, during 2006. Blood samples from patients presenting dengue-like symptoms were collected for DENV testing. We performed M-N-PCR using primers based on NS5 for virus detection and identification. The fragments were purified from PCR mixtures and sequenced. The positive dengue cases were geo-coded. To type the sequenced samples, 52 reference sequences were aligned. The dataset generated was used for iterative phylogenetic reconstruction with the maximum likelihood criterion. The best demographic model, the rate of growth, rate of evolutionary change, and Time to Most Recent Common Ancestor (TMRCA) were estimated. The basic reproductive rate during the epidemics was estimated. We obtained sequences from 82 patients among 174 blood samples. We were able to geo-code 46 sequences. The alignment generated a 399-nucleotide-long dataset with 134 taxa. The phylogenetic analysis indicated that all samples were of DENV-3 and related to strains circulating on the isle of Martinique in 2000–2001. Sixty DENV-3 from São José do Rio Preto formed a monophyletic group (lineage 1), closely related to the remaining 22 isolates (lineage 2). We assumed that these lineages appeared before 2006 in different occasions. By transforming the inferred exponential growth rates into the basic reproductive rate, we obtained values for lineage 1 of R0 = 1.53 and values for lineage 2 of R0 = 1.13. Under the exponential model, TMRCA of lineage 1 dated 1 year and lineage 2 dated 3.4 years before the last sampling. The possibility of inferring the spatio-temporal dynamics from genetic data has been generally little explored, and it may shed light on DENV circulation. The use of both geographic and temporally structured phylogenetic data provided a detailed view on the spread of at least two dengue viral strains in a populated urban area