641 research outputs found

    Mapeamento de hospedeiros de Huanglongbing (Candidatus Liberibacter SP ) no Recôncavo Baiano.

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    A citricultura brasileira representa importante segmento do agronegócio, sendo São Paulo o Estado que detém o primeiro lugar no ranking nacional da produção. Proporcionalmente à pujança da sua citricultura, ele também lidera nas ocorrências fitossanitárias, as quais têm comprometido a rentabilidade do setor

    Flutuação populacional de Diaphorina citri (Hemiptera: Psyllidae), vetor do HLB (huanglongbing) no Recôncavo da Bahia.

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    O psilídeo Diaphorina citri é, atualmente, o inseto vetor da doença mais devastadora dos citros. Ganhou esse status por ser o transmissor da bactéria Candidatus Liberibacter spp., causadora, do HLB. De origem asiática, o HLB foi detectado no Brasil em 2004 e encontra-se disseminada no estado de São Paulo, e em vários municípios de Minas Gerais e Paraná

    Comparação de testes de vigor de sementes de feijão-comum por análise visual e processamento de imagens com o software Image J.

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    O vigor de sementes pode ser estimado pelo teste tetrazólio, cuja interpretação por análise visual talvez seja lenta e sujeita a erros. O objetivo deste trabalho foi estabelecer uma rotina para análise precisa e rápida do vigor de sementes de feijão-comum (Phaseolus vulgaris L.) submetidas ao teste tetrazólio, com o Software Image J, e comparar seus resultados com os de rotina de avaliação visual, padronizada pelo Mapa

    Efeito inibidor de metabólitos não voláteis de Trichoderma spp. contra patógenos causadores de doenças radiculares em plantas de feijoeiro-comum.

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    Cepas do gênero Trichoderma podem produzir metabólitos secundários que inibem fitopatógenos, no solo ou nas raízes das plantas. Este trabalho analisou o potencial de cepas de Trichoderma em inibir in vitro os patógenos Sclerotinia sclerotiorum, Macrophomina phaseolina, Fusarium solani e Rhizoctonia solani

    Bioensaio para avaliação de Bacillus spp. no controle biológico de microescleródios de Macrophomina phaseolina.

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    As rizobactérias do gênero Bacillus possuem diversos mecanismos que beneficiam o desenvolvimento das plantas, como controle biológico, promoção do crescimento e solubilização de nutrientes. É possível que metabólitos produzidos por Bacillus spp. ajudem no combate a patógenos habitantes do solo, como Macrophomina phaseolina, que pode matar as plantas hospedeiras, principalmente sob estresse hídrico. Objetivou-se ajustar um método de seleção de Bacillus sp. antagonistas ao fungo M. phaseolina

    Efficacy, Stability, and Safety Evaluation of New Polyphenolic Xanthones Towards Identification of Bioactive Compounds to Fight Skin Photoaging

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    Antioxidants have long been used in the cosmetic industry to prevent skin photoaging, which is mediated by oxidative stress, making the search for new antioxidant compounds highly desirable in this field. Naturally occurring xanthones are polyphenolic compounds that can be found in microorganisms, fungi, lichens, and some higher plants. This class of polyphenols has a privileged scaffold that grants them several biological activities. We have previously identified simple oxygenated xanthones as promising antioxidants and disclosed as hit, 1,2-dihydroxyxanthone (1). Herein, we synthesized and studied the potential of xanthones with different polyoxygenated patterns as skin antiphotoaging ingredients. In the DPPH antioxidant assay, two newly synthesized derivatives showed IC₅₀ values in the same range as ascorbic acid. The synthesized xanthones were discovered to be excellent tyrosinase inhibitors and weak to moderate collagenase and elastase inhibitors but no activity was revealed against hyaluronidase. Their metal-chelating effect (FeCl₃ and CuCl₂) as well as their stability at different pH values were characterized to understand their potential to be used as future cosmetic active agents. Among the synthesized polyoxygenated xanthones, 1,2-dihydroxyxanthone (1) was reinforced as the most promising, exhibiting a dual ability to protect the skin against UV damage by combining antioxidant/metal-chelating properties with UV-filter capacity and revealed to be more stable in the pH range that is close to the pH of the skin. Lastly, the phototoxicity of 1,2-dihydroxyxanthone (1) was evaluated in a human keratinocyte cell line and no phototoxicity was observed in the concentration range tested.This research was supported by national funds through FCT, Foundation for Science and Technology, within the scope of UIDB/04423/2020 and UIDP/04423/2020 under the project PTDC/SAU-PUB/28736/2017 (reference POCI-01-0145-FEDER-028736), cofinanced by COMPETE 2020, Portugal 2020 and the European Union through the ERDF and by FCT through national funds, as well as CHIRALBIOACTIVE-PI-3RL-IINFACTS-2019, and supported by the Applied Molecular Biosciences Unit-UCIBIO which is financed by national funds from FCT/MCTES (UID/Multi/04378/2019). Thanks are also due to FCT, the European Union, QREN, FEDER, COMPETE, by funding cE3c center (Ref. UID/BIA/00329/2019) and Direcao Regional da Ciencia e Tecnologia (Azores Government) by funding Azorean Biodiversity Group.info:eu-repo/semantics/publishedVersio

    Liquid-Ordered Phase Formation by Mammalian and Yeast Sterols: A Common Feature With Organizational Differences

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    Here, biophysical properties of membranes enriched in three metabolically related sterols are analyzed both in vitro and in vivo. Unlike cholesterol and ergosterol, the common metabolic precursor zymosterol is unable to induce the formation of a liquid ordered (lo) phase in model lipid membranes and can easily accommodate in a gel phase. As a result, Zym has a marginal ability to modulate the passive membrane permeability of lipid vesicles with different compositions, contrary to cholesterol and ergosterol. Using fluorescence-lifetime imaging microscopy of an aminostyryl dye in living mammalian and yeast cells we established a close parallel between sterol-dependent membrane biophysical properties in vivo and in vitro. This approach unraveled fundamental differences in yeast and mammalian plasma membrane organization. It is often suggested that, in eukaryotes, areas that are sterol-enriched are also rich in sphingolipids, constituting highly ordered membrane regions. Our results support that while cholesterol is able to interact with saturated lipids, ergosterol seems to interact preferentially with monounsaturated phosphatidylcholines. Taken together, we show that different eukaryotic kingdoms developed unique solutions for the formation of a sterol-rich plasma membrane, a common evolutionary trait that accounts for sterol structural diversity.Peer Reviewe

    The Effects of Resistance Training Volume on Skeletal Muscle Proteome

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    International Journal of Exercise Science 10(7): 1051-1066, 2017. Studies are conflicting to whether low volume resistance training (RT) is as effective as high-volume RT protocols with respect to promoting morphological and molecular adaptations. Thus, the aim of the present study was to compare, using a climbing a vertical ladder, the effects of 8 weeks, 3 times per week, resistance training with 4 sets (RT4), resistance training with 8 sets (RT8) and without resistance training control (CON) on gastrocnemius muscle proteome using liquid chromatography mass spectrometry (LC-MS/MS) and cross sectional area (CSA) of rats. Fifty-two proteins were identified by LC-MS/MS, with 39 in common between the three groups, two in common between RT8 and CON, one in common between RT8 and RT4, four exclusive in the CON, one in the RT8, and four in the RT4. The RT8 group had a reduced abundance of 12 proteins, mostly involved in muscle protein synthesis, carbohydrate metabolism, tricarboxylic acid cycle, anti-oxidant defense, and oxygen transport. Otherwise one protein involved with energy transduction as compared with CON group showed high abundance. There was no qualitative protein abundance difference between RT4 and CON groups. These results revealed that high volume RT induced undesirable disturbances on skeletal muscle proteins, while lower volume RT resulted in similar gains in skeletal muscle hypertrophy without impairment of proteome. The CSA was significantly higher in RT8 group when compared to RT4 group, which was significantly higher than CON group. However, no differences were found between trained groups when the gastrocnemius CSA were normalized by the total body weight

    Portuguese Ministers, 1851-1999: Social Background and Paths to Power

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    Disponível em: http://193.136.113.6/Opac/Pages/Search/Results.aspx?SearchText=UID=bb8aa8d5-c6b6-466a-81bb-fe8a67693cee&DataBase=10449_UNLFCSHThis paper provides an empirical analysis of the impact of regime changes in the composition and patterns of recruitment of the Portuguese ministerial elite throughout the last 150 years. The ‘out-of-type’, violent nature of most regime transformations accounts for the purges in and the extensive replacements of the political personnel, namely of the uppermost officeholders. In the case of Cabinet members, such discontinuities did not imply, however, radical changes in their social profile. Although there were some significant variations, a series of salient characteristics have persisted over time. The typical Portuguese minister is a male in his midforties, of middle-class origin and predominantly urban-born, highly educated and with a state servant background. The two main occupational contingents have been university professors - except for the First Republic (1910-26) - and the military, the latter having only recently been eclipsed with the consolidation of contemporary democracy. As regards career pathways, the most striking feature is the secular trend for the declining role of parliamentary experience, which the democratic regime did not clearly reverse. In this period, a technocratic background rather than political experience has been indeed the privileged credential for a significant proportion of minister

    Space-time singularities in Weyl manifolds

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    We extend one of the Hawking-Penrose singularity theorems in general relativity to the case of some scalar-tensor gravity theories in which the scalar field has a geometrical character and space-time has the mathematical structure of a Weyl integrable space-time (WIST). We adopt an invariant formalism, so that the extended version of theorem does not depend on a particular frame.Comment: 16 page
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