982 research outputs found

    Biopolymer-based membranes associated with osteogenic growth peptide for guided bone regeneration

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    Barrier membranes for guided bone regeneration (GBR) mainly promote mechanical maintenance of bone defect space and induce osteopromotion. Additionally, biopolymer-based membranes may provide greater bioactivity and biocompatibility due to their similarity to extracellular matrix (ECM).In this study, biopolymers-based membranes from bacterial cellulose (BC) and collagen (COL) associated with osteogenic growth peptide (OGP(10–14)) were evaluated to determine in vitro osteoinductive potential in early osteogenesis; moreover, histological study was performed to evaluate the BC–COL OGP(10–14) membranes on bone healing after GBR in noncritical defects in rat femur. The results showed that the BC–COL and BC–COL OGP(10–14) membranes promoted cell proliferation and alkaline phosphatase activity in osteoblastic cell cultures. However, ECMmineralization was similar between cultures grown on BC OGP(10–14) and BC–COL OGP(10–14) membranes. In vivo results showed that all the membranes tested, including the peptide-free BC membrane, promoted better bone regeneration than control group. Furthermore, the BC–COL OGP(10–14) membranes induced higher radiographic density in the repaired bone than the other groups at 1, 4 and 16 weeks. Histomorpho-metric analyses revealed that the BC–COL OGP(10–14) induced higher percentage of bone tissue in the repaired area at 2 and 4 weeks than others membranes. In general, these biopolymer-based membranes might be potential candidates for bone regeneration applications

    Avaliação de cultivares de soja, sob manejo orgânico, para fins de adubação verde e produção de grãos.

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    O objetivo deste trabalho foi avaliar o desempenho de seis cultivares de soja, sob manejo orgânico, para fins de adubação verde e produção de grãos. Utilizou-se delineamento experimental de blocos casualizados, com quatro repetições por tratamento (cultivar). Na época da colheita, 81 dias após a emergência das plântulas, todas as cultivares testadas (Celeste, Surubi, Campo Grande, Mandi, Lambari e Taquari) mostraram excelente nodulação, variando de 545 a 760 mg/planta de massa nodular seca. As cultivares Celeste e Taquari, que produziram, respectivamente, 8,33 e 7,12 t ha-1 de biomassa seca da parte aérea, apresentaram outras características agronômicas vantajosas, tais como: ciclo curto, alta acumulação de nutrientes (N, P, K, Ca e Mg) nos tecidos verdes e bom rendimento de sementes. Esses caracteres indicam potencial de 'Celeste' e 'Taquari' para adubação verde de verão em sistemas de agricultura orgânica. Cinco das cultivares avaliadas revelaram tendência ao acamamento, porém dentro de níveis aceitáveis. As cultivares Celeste, Surubi, Campo Grande, Mandi e Taquari suplantaram em 23%, 32%, 33%, 44% e 70%, respectivamente, a média nacional de produtividade de soja, estimada em 2.398 kg ha-1 nas últimas três safras

    High connectivity of the Crocodile Shark between the Atlantic and Southwest Indian Oceans: highlights for conservation

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    Among the various shark species that are captured as bycatch in commercial fishing operations, the group of pelagic sharks is still one of the least studied and known. Within those, the crocodile shark, Pseudocarcharias kamoharai, a small-sized lamnid shark, is occasionally caught by longline vessels in certain regions of the tropical oceans worldwide. However, the population dynamics of this species, as well as the impact of fishing mortality on its stocks, are still unknown, with the crocodile shark currently one of the least studied of all pelagic sharks. Given this, the present study aimed to assess the population structure of P. kamoharai in several regions of the Atlantic and Indian Oceans using genetic molecular markers. The nucleotide composition of the mitochondrial DNA control region of 255 individuals was analyzed, and 31 haplotypes were found, with an estimated diversity Hd = 0.627, and a nucleotide diversity pi = 0.00167. An analysis of molecular variance (AMOVA) revealed a fixation index phi(ST) = -0.01118, representing an absence of population structure among the sampled regions of the Atlantic Ocean, and between the Atlantic and Indian Oceans. These results show a high degree of gene flow between the studied areas, with a single genetic stock and reduced population variability. In panmictic populations, conservation efforts can be concentrated in more restricted areas, being these representative of the total biodiversity of the species. When necessary, this strategy could be applied to the genetic maintenance of P. kamoharai.Foundation for Research Support of the Sao Paulo State - FAPESP [2011/23787-0, 2010/51903-2]; Portuguese Foundation for Science and Technology (FCT) [SFRH/BPD/93936/2013]; Foundation for Research Support of the Sao Paulo State - FAPESP [2011/23787-0, 2010/51903-2]; Portuguese Foundation for Science and Technology (FCT) [SFRH/BPD/93936/2013]info:eu-repo/semantics/publishedVersio

    Psicología Y educación a distancia : una revisión de la literatura

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    O presente estudo investigou as contribuições da Psicologia para a educação a distância – EAD. Para isso, realizou-se revisão bibliográfica de publicações nacionais, entre 1999 e 2009, nas bases de dados SciELO, Lilacs, PsycINFO, BVS e Google Acadêmico. Foram selecionados 69 estudos, dos quais se excluíram 15, por não serem compatíveis com a pesquisa. Os resultados evidenciaram nove eixos temáticos: (1) tecnologia educacional a distância com fundamentos psicológicos, (2) afeição, (3) papel do tutor/professor, (4) teorias psicológicas, (5) interatividade, (6) evasão, (7) relatos de experiências, (8) avaliação de treinamento, desenvolvimento e educação a distância e (9) outros. Os temas tecnologia educacional a distância com fundamentos psicológicos e afeição obtiveram maior frequência nas publicações. Neste estudo, registrou-se, também, que, embora em ascensão desde 2006, os anos de maiores publicações da Psicologia na educação a distância foram 2008 e 2009. Sugere-se que estudos futuros ampliem esta pesquisa para incluir bases de dados internacionais.This study investigated the contributions of Psychology to Distance Learning. A literature review of national publications between 1999 to 2009 was made in the electronic databases SciELO, LILACS, PsycINFO, BVS and Google Scholar. From the 69 studies selected, 15 were excluded because they were not compatible with the research. The results showed nine themes: (1) the distance learning technology with psychological grounding, (2) affection, (3)the role of the tutor/professor, (4) psychological theories, (5) interactivity, (6) dropout, (7) reports of experiences, (8) assessment of distance training, development and education and (9) others. The topics distance education technology with psychological grounding and affection had a larger frequency in the publications. Since 2006, there was an increasing number of publications in psychology distance education, but the years of major publications were from 2008 to 2009. It is suggested that future studies expand this research including international databases.El presente estudio investigó las contribuciones de la Psicología para la Educación a Distancia – EAD. Para eso, fue realizada una revisión bibliográfica de publicaciones nacionales, entre 1999 y 2009 en las bases de datos SciELO, Lilacs, PsycINFO, BVS y Google Académico. Fueron seleccionados 69 estudios, de los cuales se excluyeron 15, por no ser compatibles con la pesquisa. Los resultados evidenciaron nueve ejes temáticos (1) tecnología educacional la distancia con fundamentos psicológicos; (2) afección; (3) papel del tutor/profesor; (4) teorías psicológicas; (5) interactividad; (6) evasión; (7) relatos de experiencias, (8) evaluación de entrenamiento, desarrollo y educación distancia y (9) otros. Los temas tecnología educacional a distancia con fundamentos psicológicos y afección obtuvieron mayor frecuencia en las publicaciones. En ese estudio se registró, también, que, aunque en ascensión desde 2006, los años de mayores publicaciones de la psicología en la educación a distancia, fueron 2008 y 2009. Se sugiere que estudios futuros amplíen esa pesquisa para incluir bases de datos internacionales

    Effects of Glyphosate and its Formulation, Roundup, on Reproduction in Zebrafish (Danio rerio)

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    This is an open access article that is freely available in ORE or from the publisher's web site. Please cite the published version.Copyright © 2014 American Chemical SocietyRoundup and its active ingredient glyphosate are among the most widely used herbicides worldwide and may contaminate surface waters. Research suggests both Roundup and glyphosate induce oxidative stress in fish and may also cause reproductive toxicity in mammalian systems. We aimed to investigate the reproductive effects of Roundup and glyphosate in fish and the potential associated mechanisms of toxicity. To do this, we conducted a 21-day exposure of breeding zebrafish (Danio rerio) to 0.01, 0.5, and 10 mg/L (glyphosate acid equivalent) Roundup and 10 mg/L glyphosate. 10 mg/L glyphosate reduced egg production but not fertilization rate in breeding colonies. Both 10 mg/L Roundup and glyphosate increased early stage embryo mortalities and premature hatching. However, exposure during embryogenesis alone did not increase embryo mortality, suggesting that this effect was caused primarily by exposure during gametogenesis. Transcript profiling of the gonads revealed 10 mg/L Roundup and glyphosate induced changes in the expression of cyp19a1 and esr1 in the ovary and hsd3b2, cat, and sod1 in the testis. Our results demonstrate that these chemicals cause reproductive toxicity in zebrafish, although only at high concentrations unlikely to occur in the environment, and likely mechanisms of toxicity include disruption of the steroidogenic biosynthesis pathway and oxidative stress.Natural Environment Research Counci

    The Echinococcus canadensis (G7) genome: A key knowledge of parasitic platyhelminth human diseases

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    Background: The parasite Echinococcus canadensis (G7) (phylum Platyhelminthes, class Cestoda) is one of the causative agents of echinococcosis. Echinococcosis is a worldwide chronic zoonosis affecting humans as well as domestic and wild mammals, which has been reported as a prioritized neglected disease by the World Health Organisation. No genomic data, comparative genomic analyses or efficient therapeutic and diagnostic tools are available for this severe disease. The information presented in this study will help to understand the peculiar biological characters and to design species-specific control tools. Results: We sequenced, assembled and annotated the 115-Mb genome of E. canadensis (G7). Comparative genomic analyses using whole genome data of three Echinococcus species not only confirmed the status of E. canadensis (G7) as a separate species but also demonstrated a high nucleotide sequences divergence in relation to E. granulosus (G1). The E. canadensis (G7) genome contains 11,449 genes with a core set of 881 orthologs shared among five cestode species. Comparative genomics revealed that there are more single nucleotide polymorphisms (SNPs) between E. canadensis (G7) and E. granulosus (G1) than between E. canadensis (G7) and E. multilocularis. This result was unexpected since E. canadensis (G7) and E. granulosus (G1) were considered to belong to the species complex E. granulosus sensu lato. We described SNPs in known drug targets and metabolism genes in the E. canadensis (G7) genome. Regarding gene regulation, we analysed three particular features: CpG island distribution along the three Echinococcus genomes, DNA methylation system and small RNA pathway. The results suggest the occurrence of yet unknown gene regulation mechanisms in Echinococcus. Conclusions: This is the first work that addresses Echinococcus comparative genomics. The resources presented here will promote the study of mechanisms of parasite development as well as new tools for drug discovery. The availability of a high-quality genome assembly is critical for fully exploring the biology of a pathogenic organism. The E. canadensis (G7) genome presented in this study provides a unique opportunity to address the genetic diversity among the genus Echinococcus and its particular developmental features. At present, there is no unequivocal taxonomic classification of Echinococcus species; however, the genome-wide SNPs analysis performed here revealed the phylogenetic distance among these three Echinococcus species. Additional cestode genomes need to be sequenced to be able to resolve their phylogeny.Fil: Maldonado, Lucas Luciano. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Assis, Juliana. Fundación Oswaldo Cruz; BrasilFil: Gomes Araújo, Flávio M.. Fundación Oswaldo Cruz; BrasilFil: Salim, Anna C. M.. Fundación Oswaldo Cruz; BrasilFil: Macchiaroli, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Cucher, Marcela Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Camicia, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Fox, Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Rosenzvit, Mara Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Oliveira, Guilherme. Instituto Tecnológico Vale; Brasil. Fundación Oswaldo Cruz; BrasilFil: Kamenetzky, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentin

    Disclosing ambiguous gene aliases by automatic literature profiling

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    Submitted by Nuzia Santos ([email protected]) on 2015-01-14T10:55:18Z No. of bitstreams: 1 Disclosing ambiguous gene aliases by automatic.pdf: 217573 bytes, checksum: ce54aa2c4ea49eb989f9e7308d827ce6 (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2015-01-14T10:55:25Z (GMT) No. of bitstreams: 1 Disclosing ambiguous gene aliases by automatic.pdf: 217573 bytes, checksum: ce54aa2c4ea49eb989f9e7308d827ce6 (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2015-01-14T11:01:59Z (GMT) No. of bitstreams: 1 Disclosing ambiguous gene aliases by automatic.pdf: 217573 bytes, checksum: ce54aa2c4ea49eb989f9e7308d827ce6 (MD5)Made available in DSpace on 2015-01-14T11:01:59Z (GMT). No. of bitstreams: 1 Disclosing ambiguous gene aliases by automatic.pdf: 217573 bytes, checksum: ce54aa2c4ea49eb989f9e7308d827ce6 (MD5) Previous issue date: 2010Fundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Centro de Excelência em Bioinformática. Belo Horizonte, MG, Brasil/Fundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Grupo de Genômica e Biologia Computacional. Belo Horizonte, MG, BrasilGlaxoSmithKline Moore Dr. Molecular Discovery Research. Research Triangle Park, NC, USAFundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Centro de Excelência em Bioinformática. Belo Horizonte, MG, Brasil/Fundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Grupo de Genômica e Biologia Computacional. Belo Horizonte, MG, BrasilBackground Retrieving pertinent information from biological scientific literature requires cutting-edge text mining methods which may be able to recognize the meaning of the very ambiguous names of biological entities. Aliases of a gene share a common vocabulary in their respective collections of PubMed abstracts. This may be true even when these aliases are not associated with the same subset of documents. This gene-specific vocabulary defines a unique fingerprint that can be used to disclose ambiguous aliases. The present work describes an original method for automatically assessing the ambiguity levels of gene aliases in large gene terminologies based exclusively in the content of their associated literature. The method can deal with the two major problems restricting the usage of current text mining tools: 1) different names associated with the same gene; and 2) one name associated with multiple genes, or even with non-gene entities. Important, this method does not require training examples. Results Aliases were considered “ambiguous” when their Jaccard distance to the respective official gene symbol was equal or greater than the smallest distance between the official gene symbol and one of the three internal controls (randomly picked unrelated official gene symbols). Otherwise, they were assigned the status of “synonyms”. We evaluated the coherence of the results by comparing the frequencies of the official gene symbols in the text corpora retrieved with their respective “synonyms” or “ambiguous” aliases. Official gene symbols were mentioned in the abstract collections of 42 % (70/165) of their respective synonyms. No official gene symbol occurred in the abstract collections of any of their respective ambiguous aliases. In overall, querying PubMed with official gene symbols and “synonym” aliases allowed a 3.6-fold increase in the number of unique documents retrieved. Conclusions These results confirm that this method is able to distinguish between synonyms and ambiguous gene aliases based exclusively on their vocabulary fingerprint. The approach we describe could be used to enhance the retrieval of relevant literature related to a gen
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