501 research outputs found

    Toward in vitro fertilization in Brachiaria spp.

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    Brachiaria are forage grasses widely cultivated in tropical areas. In vitro pollination was applied to accessions of Brachiaria spp. by placing pollen of non-dehiscent anthers on a solid medium near isolated ovaries. Viability and in vitro germination were tested in order to establish good conditions for pollen development. Comparing sexual to apomictic plants, apomictic pollen has more abortion after meiosis during the microspore stage and a lower viability and, of both types, only some plants have sufficient germination in a high sugar concentration. Using in vitro pollination with the sexual plant, the pollen tube penetrates into the nucellus and micropyle, but the embryo sac degenerates and collapses. In the apomictic B. decumbens, in vitro pollination leads to the transfer of the sperm nuclei into the egg cell and the central cell. The results are discussed according to normal fertilization and barriers in sexual and apomictic plants

    How seasonality and anthropogenic impacts can modulate the structure of aquatic benthic invertebrate assemblages

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    We studied a benthic invertebrate assemblage of a stream that passes through pristine, rural, suburban and urban areas of a municipality located in southeastern Brazil to investigate a possible relationship between this assemblage structure and urbanization. The environmental variables and fauna structure were analyzed in a spatial and temporal scale, sampling the four sites in a dry and wet season. We found a clear spatial pattern, with higher similarity between sites from rural and suburban area that presented intermediate environmental characteristics. The pristine site showed in both seasons the lowest values of alkalinity and fecal coliform. On the other hand, the site located in the urban area showed the lowest concentration of dissolved oxygen and higher of suspended solids, ammonia and fecal coliform. The extreme values of these three variables occurred in the wet season, probably related to the high rainfall values. The benthic invertebrate fauna structure followed the same longitudinal and seasonal pattern found for the environmental variables. The site in urban area showed the lowest richness, diversity and evenness, with a dominance of two groups resistant to adverse environmental conditions (Oligochaeta and Orthocladiinae) and absence of more sensitive groups (Coleoptera, Ephemeroptera and Trichoptera). The increase drag of the substrate and associated invertebrates can be responsible for the lower abundance and richness observed in the wet season. The environmental variables that best defined the differentiation between sites (dissolved oxygen, organic suspended solids and fecal coliform) related directly to urbanization effects, like dump effluents and removal of riparian vegetation. | Supporting Information Supporting Information </supplementary-material

    Rho GTPase activating protein 21-mediated regulation of prostate cancer associated 3 gene in prostate cancer cell

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    The overexpression of the prostate cancer antigen 3 (PCA3) gene is well-defined as a marker for prostate cancer (PCa) diagnosis. Although widely used in clinical research, PCA3 molecular mechanisms remain unknown. Herein we used phage display technology to identify putative molecules that bind to the promoter region of PCA3 gene and regulate its expression. The most frequent peptide PCA3p1 (80%) was similar to the Rho GTPase activating protein 21 (ARHGAP21) and its binding affinity was confirmed using Phage Bead ELISA. We showed that ARHGAP21 silencing in LNCaP prostate cancer cells decreased PCA3 and androgen receptor (AR) transcriptional levels and increased prune homolog 2 (PRUNE2) coding gene expression, indicating effective involvement of ARHGAP21 in androgen-dependent tumor pathway. Chromatin immunoprecipitation assay confirmed the interaction between PCA3 promoter region and ARHGAP21. This is the first study that described the role of ARHGAP21 in regulating the PCA3 gene under the androgenic pathway, standing out as a new mechanism of gene regulatory control during prostatic oncogenesis

    Simultaneous determination of antiretroviral zidovudine, lamivudine and efavirenz by RP HPLC-DAD

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    A reverse phase high-performance liquid chromatography-photodiode array detector (RP HPLC-DAD) method for simultaneous determination of lamivudine (3TC), zidovudine (AZT), two nucleoside reverse transcriptase inhibitors, and efavirenz (EFV), a non-nucleoside reverse transcriptase inhibitor, in tablets is described. The drugs separation was performed on a C18 column (250 x 4,6 mm, 5 μm - Phenomenex®), through a mobile phase drag composed by a binary gradient of acetonitrile and water HPLC grade. The drugs detection was performed at 248 nm, resulting in a 14 min chromatographic run. The samples were prepared by crushing tablets, weighing powder, diluting it by a 10 min sonication and filtrating solution, resulting in samples with final concentration of 20, 40 e 40 μg.mL–1 of 3TC, AZT and EFV, respectively. The method was adequate for quality control purposes and was validated following the ICH guidelines.Colegio de Farmacéuticos de la Provincia de Buenos Aire

    Chronic Hepatitis C treatment for genotype 2 or 3 in Brazil: cost effectiveness analysis of peginterferon plus ribavirin as first choice treatment

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    Brazilian Guidelines to HCV treatment (2007) recommended that the first choice treatment for patients with chronic hepatitis C (CHC) and genotype 2 or 3 is interferon alpha (IFN) plus ribavirin (RBV) for 24 weeks. The aim of this study is compare the cost and effectiveness to Hepatitis C treatment in patients with genotype 2 or 3 of peginterferon alpha (PEG) as the first choice of treatment within PEG for those that do not respond to IFN. The target population is CHC patients with genotype 2 or 3 in Brazil. The interventions are: PEG-SEC (first IFN plus RBV for 24 weeks, after, for non-responders and relapsers subsequently PEG plus RBV for 48 weeks); PEG-FIRST24 (PEG+RBV for 24 weeks). The type of the study is cost-effectiveness analysis. The data sources are: Effectiveness data from meta-analysis conducted on the Brazilian population. Treatment cost from Brazilian micro costing study is converted into USD (2010). The perspective is the Public Health System. The outcome measurements are Sustained Viral Response (SVR) and costs. PEG-FIRST24 (SVR: 87.8%, costs: USD 8,338.27) was more effective and more costly than PEG-SEC (SVR: 79.2%, costs: USD 5,852.99). The sensitivity analyses are: When SVR rates with IFN was less than 30% PEG-FIRST is dominant. On the other hand, when SVR with IFN was more then 75% PEG-SEC is dominant (SVR=88.2% and costs USD $ 3,753.00). PEG-SEC is also dominant when SVR to PEG24 weeks was less than 54%. In the Brazilian context, PEG-FIRST is more effective and more expensive than PEG-SEC. PEG-SEC could be dominant when rates of IFN therapy are higher than 75% or rates of PEG24 therapy are lower than 54%

    O PORTAL DO CADERNO DE CIDADANIA COMO FERRAMENTA DE INCLUSÃO DIGITAL

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    Este artigo trata do desenvolvimento de um portal digital para divulgar as ações executadas pelo projeto de extensão da UNIVALI/Cejurps - Programa de Formação e Assessoria em Cidadania Infanto-juvenil - que possui o objetivo de ser uma ferramenta de inclusão digital para crianças e adolescentes. No portal existe um espaço para divulgar novidades, eventos, publicação de artigos, novas parcerias e um fórum para manter contato com os administradores e esclarecer dúvidas na interação com as crianças e os adolescentes. No trabalho de extensão foi utilizado para elaboração do portal e do jogo digital o método indutivo, já que cada etapa foi elaborada e trabalhada detalhadamente para obter-se o resultado final, qual seja, o sítio na internet, com a criação de um jogo digital. O método de procedimento foi o empírico, já que se obteve o auxílio de crianças e adolescentes para a elaboração de cada etapa, fortalecendo o papel da criança como ator social, na busca de um resultado mais efetivo e condizendo com a realidade das crianças
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