736 research outputs found

    Ultrasound intensification suppresses the need of methanol excess during the biodiesel production with Lipozyme TL-IM

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    The synthesis of biodiesel from sunflower oil and methanol based on transesterification using the immobilized lipase from Thermomyces lanuginosus (Lipozyme TL-IM) has been investigated under silent conditions and under an ultrasound field. Ultrasound assisted process led to reduced processing time and requirement of lower enzyme dosage. We found for the first time that ratio 1:3 (oil to methanol) was favoured for the ultrasound assisted enzymatic process which is lower as that favoured for the silent process (ratio of 1.4). Our results indicate that intensification provided by ultrasound suppresses the need of the excess of the methanol reactant during the enzymatic biodiesel production. Ultrasound assisted enzymatic biodiesel production is therefore a faster and a cleaner processes.The authors acknowledge Brenntag India Pvt. Ltd. for kindly providing gift sample of lipase enzyme Lipozyme TL IM to carry out the research work. All authors acknowledge the funding of Department of Science and Technology and Portuguese Science Foundation under the Indo-Portuguese collaborative program

    Early Cardiac Mitochondrial Molecular and Functional Responses to Acute Anthracycline Treatment in Wistar Rats

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    Doxorubicin (DOX) is an anticancer drug widely used to treat human and nonhuman tumors but the late and persistent cardio-toxicity reduces the therapeutic utility of the drug. The full mechanism(s) of DOX-induced acute, subchronic and delayed toxicity, which has a preponderant mitochondrial component, remains unclear; therefore, it is clinically relevant to identify early markers to identify patients who are predisposed to DOX-related cardiovascular toxicity. To address this, Wistar rats (16 weeks old) were treated with a single DOX dose (20 mg/kg, i.p.); then, mRNA, protein levels and functional analysis of mitochondrial endpoints were assessed 24 h later in the heart, liver, and kidney. Using an exploratory data analysis, we observed cardiac-specific alterations after DOX treatment for mitochondrial complexes III, IV, and preferentially for complex I. Conversely, the same analysis revealed complex II alterations are associated with DOX response in the liver and kidney. Interestingly, H2O2 production by the mitochondrial respiratory chain as well as loss of calcium-loading capacity, markers of subchronic toxicity, were not reliable indicators of acute DOX cardiotoxicity in this animal model. By using sequential principal component analysis and feature correlation analysis, we demonstrated for the first time alterations in sets of transcripts and proteins, but not functional measurements, that might serve as potential early acute markers of cardiac-specific mitochondrial toxicity, contributing to explain the trajectory of DOX cardiac toxicity and to develop novel interventions to minimize DOX cardiac liabilities

    Spatial Factors Play a Major Role as Determinants of Endemic Ground Beetle Beta Diversity of Madeira Island Laurisilva

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    The development in recent years of new beta diversity analytical approaches highlighted valuable information on the different processes structuring ecological communities. A crucial development for the understanding of beta diversity patterns was also its differentiation in two components: species turnover and richness differences. In this study, we evaluate beta diversity patterns of ground beetles from 26 sites in Madeira Island distributed throughout Laurisilva – a relict forest restricted to the Macaronesian archipelagos. We assess how the two components of ground beetle beta diversity (βrepl – species turnover and βrich - species richness differences) relate with differences in climate, geography, landscape composition matrix, woody plant species richness and soil characteristics and the relative importance of the effects of these variables at different spatial scales. We sampled 1025 specimens from 31 species, most of which are endemic to Madeira Island. A spatially explicit analysis was used to evaluate the contribution of pure environmental, pure spatial and environmental spatially structured effects on variation in ground beetle species richness and composition. Variation partitioning showed that 31.9% of species turnover (βrepl) and 40.7% of species richness variation (βrich) could be explained by the environmental and spatial variables. However, different environmental variables controlled the two types of beta diversity: βrepl was influenced by climate, disturbance and soil organic matter content whilst βrich was controlled by altitude and slope. Furthermore, spatial variables, represented through Moran’s eigenvector maps, played a significant role in explaining both βrepl and βrich, suggesting that both dispersal ability and Madeira Island complex orography are crucial for the understanding of beta diversity patterns in this group of beetles.Peer reviewe

    Development of novel magnetoliposomes containing nickel ferrite nanoparticles covered with gold for applications in thermotherapy

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    Multifunctional nanosystems combining magnetic and plasmonic properties are a promising approach for cancer therapy, allowing magnetic guidance and a local temperature increase. This capability can provide a triggered drug release and synergistic cytotoxic effect in cancer cells. In this work, nickel ferrite/gold nanoparticles were developed, including nickel ferrite magnetic nanoparticles decorated with plasmonic gold nanoparticles and core/shell nanostructures (with a nickel ferrite core and a gold shell). These nanoparticles were covered with a surfactant/lipid bilayer, originating liposome-like structures with diameters below 160 nm. The heating capacity of these systems, upon excitation with light above 600 nm wavelength, was assessed through the emission quenching of rhodamine B located in the lipid layer. The developed nanosystems show promising results for future applications in thermotherapy.This research was funded by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding of CF-UM-UP (UID/FIS/04650/2019) and through the research project PTDC/QUI-QFI/28020/2017 (POCI-01-0145-FEDER-028020), financed by European Fund of Regional Development (FEDER), COMPETE2020, and Portugal2020. The magnetic measurements were supported by projects UTAP-EXPL/NTec/0046/2017, NORTE-01-0145-FEDER-028538, and PTDC/FIS-MAC/29454/2017. I.S.R.R. acknowledges FCT for a research grant under CF-UM-UP Strategic Funding (UID/FIS/04650/2019)

    State of the Art in the Studies on Crotamine, a Cell Penetrating Peptide from South American Rattlesnake

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    Animal venoms comprise a naturally selected cocktail of bioactive peptides/proteins and other molecules, each of which playing a defined role thanks to the highly specific interactions with diverse molecular targets found in the prey. Research focused on isolation, structural, and functional characterizations of novel natural biologics (bioactive peptides/proteins from natural sources) has a long way to go through from the basic science to clinical applications. Herein, we overview the structural and functional characteristics of the myoneurotoxin crotamine, firstly isolated from the South American rattlesnake venom. Crotamine is the first venom peptide classified as a natural cell penetrating and antimicrobial peptide (CPP and AMP) with a more pronounced antifungal activity. in contrast to other known natural CPPs and AMPs, crotamine demonstrates a wide spectrum of biological activities with potential biotechnological and therapeutic values. More recent studies have demonstrated the selective in vitro anticancer activity of crotamine. in vivo, using a murine melanoma model, it was shown that crotamine delays tumor implantation, inhibits tumor cells proliferation, and also increases the survival of mice engrafted with subcutaneous melanoma. the structural and functional properties and also the possible biotechnological applications of minimized molecules derived from crotamine are also discussed.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Inst Butantan, Genet Lab, BR-05503900 São Paulo, BrazilUniversidade Federal de São Paulo UNIFESP, Dept Farmacol, São Paulo, BrazilUniv Fed Ceara, Labomar Inst Ciencias Mar, Fortaleza, CE, BrazilUniv Estado Amazonas, Manaus, AM, BrazilCBA, Lab Bioquim & Biol Mol, Manaus, AM, BrazilUniversidade Federal de São Paulo UNIFESP, Dept Farmacol, São Paulo, BrazilWeb of Scienc

    Magnetic liposomes containing calcium ferrite nanoparticles for breast cancer therapy

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    In this work, calcium ferrite nanoparticles were prepared and characterized. The structural and magnetic properties of the nanoparticles were evaluated by XRD, TEM and SQUID. The synthesized nanoparticles were either entrapped in liposomes, originating aqueous magnetoliposomes (AMLs), or covered with a lipid bilayer, forming solid magnetoliposomes (SMLs). Magnetoliposomes present average diameters around 150 nm, suitable for biomedical applications. The magnetoliposomes were loaded with new potential anticancer drugs, thienopyridine derivatives, with a strong antitumor activity against breast cancer cells.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding of CF-UM-UP (UID/FIS/04650/2013) and of CQUM (UID/QUI/00686/2013). FCT, POPH-QREN and FSE are acknowledged for the PhD grants of A. R. O. Rodrigues (SFRH/BD/90949/2012) and V. A. Machado (SFRH/BD/77373/2011) and for financial support to MAP-Fis Joint Doctoral Programme.info:eu-repo/semantics/publishedVersio

    A utilização do ATLANTIS – Tierra 2.0 e de ferramentas SIG para predizer a distribuição espacial e a adequação do habitat de espécies endémicas

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    O conhecimento da distribuição de espécies raras requer muito esforço devido às dificuldades inerentes à detecção das suas populações. Neste capítulo, apresenta-se um exemplo de modelação da distribuição potencial de espécies endémicas de insectos, que constituem uma preocupação de conservação nos Açores. São analisados dados extraídos da base de dados ATLANTIS com o objectivo de desenvolver mapas preditivos da distribuição de quatro escaravelhos endémicos (Insecta, Coleoptera) na ilha Terceira: Cedrorum azoricus azoricus Borges & Serrano, 1993; Trechus terceiranus Machado, 1988; Trechus terrabravensis Borges, Serrano & Amorim, 2004; e Alestrus dolosus (Crotch, 1867). São usadas duas técnicas amplamente aplicadas nestas situações (BIOCLIM e BioMapper) de forma a desenvolver os mapas de distribuição, mas igualmente a obter a descrição do nicho ecológico de cada espécie. Todas as espécies, excepto T. terceiranus, apresentam grandes restrições de habitat. As outras três espécies parecem estar ambientalmente restringidas a duas áreas espaciais bem definidas, localizadas nas partes oeste (Serra de Santa Bárbara) e central (Terra Brava) da ilha Terceira. Contudo, enquanto A. dolosus estará potencialmente espalhado em ambas as áreas, de acordo com os seus requisitos de habitat, C. azoricus azoricus e T. terrabravensis parecem possuir adaptações ambientais muito mais restritivas. No entanto, como os dados sobre a distribuição conhecida destas espécies se revelaram escassos, a eficácia dos mapas de predição não é propriamente a ideal. Deste modo, é discutida de forma exaustiva a utilidade das técnicas utilizadas, num contexto de gestão da conservação. São igualmente discutidos os problemas surgidos durante o processo de modelação dos dados e como estes podem ser resolvidos. Finalmente são apresentadas sugestões para melhorar a informação a obter da base de dados ATLANTIS.ABSTRACT: Ranges of rare species require great efforts to be mapped due to the low detect ability of their populations. In this chapter, we provide an example focusing on several endemic insect species of conservation concern in the Azores. We explore the use of data extracted from ATLANTIS database to develop predictive maps of the distribution of four endemic beetle species (Insecta, Coleoptera) in Terceira Island: Cedrorum azoricus azoricus Borges & Serrano, 1993; Trechus terceiranus Machado, 1988; Trechus terrabravensis Borges, Serrano & Amorim, 2004; and Alestrus dolosus (Crotch, 1867). We use two widely used methodologies (BIOCLIM and BioMapper) to develop such maps, as well as to provide a description of the niche of these species. All species except for T. terceiranus presented highly restricted habitat requirements. The other three species seem to be environmentally restricted to two spatially well-defined areas, placed in the west (Serra de Santa Bárbara) and the centre of the island (Terra Brava). However, while A. dolosus seems to be potentially widespread in these two areas according to its habitat requirements, C. azoricus azoricus and T. terrabravensis appear to have very restricted environmental adaptations. As data (recorded presences) for these species is scarce, the performance of the predictions was not ideal. Therefore, we discuss extensively the utility of such methodologies in the context of conservation management. We also discuss how the problems arose during this work can be overcome, and how ATLANTIS information could be improved

    Magnetic/plasmonic liposomes as nanocarriers for novel antitumor tricyclic lactones against non-small cell lung cancer

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    In this work, MnFe2O4/Au core/shell nanoparticles (NPs) and MnFe2O4 NPs decorated with Au NPs were synthesized and the structural, spectroscopic and magnetic properties evaluated. The prepared NPs were covered with a lipid bilayer, forming solid magnetoliposomes (SMLs). The heating capabilities of the nanosystems were assessed through the fluorescence quenching of Nile Red (incorporated in the lipid bilayer of the SMLs) under irradiation.UIDB/04650/2020; PTDC/QUI-QFI/28020/2017 (POCI-01-0145-FEDER-028020

    Ranking protected areas in the Azores using standardised sampling of soil epigean arthropods

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    Copyright © Springer 2005.Nineteen areas in seven of the nine Azorean islands were evaluated for species diversity and rarity based on soil epigean arthropods. Fifteen out of the 19 study areas are managed as Natural Forest Reserves and the remaining four were included due to their importance as indigenous forest cover. Four of the 19 areas are not included in the European Conservation network, NATURA 2000. Two sampling replicates were run per study area, and a total of 191 species were collected; 43 of those species (23%) are endemic to the archipelago and 12 have yet to be described. To produce an unbiased multiple-criteria index (importance value for conservation, IV-C) incorporating diversity and rarity based indices, an iterative partial multiple regression analysis was performed. In addition, an irreplaceability index and the complementarity method (using both optimisation and heuristic methods) were used for priority-reserves analyses. It was concluded that at least one well-managed reserve per island is absolutely necessary to have a good fraction of the endemic arthropods preserved. We found that for presence/absence data the suboptimal complementarity algorithm provides solutions as good as the optimal algorithm. For abundance data, optimal solutions indicate that most reserves are needed if we want that at least 50% of endemic arthropod populations are represented in a minimum set of reserves. Consistently, two of the four areas not included in the NATURA 2000 framework were considered of high priority, indicating that vascular plants and bird species used to determine NATURA 2000 sites are not good surrogates of arthropod diversity in the Azores. The most irreplaceable reserves are those located in older islands, which indicates that geological history plays an important role in explaining faunal diversity of arthropods in the Azores. Based both on the uniqueness of species composition and high species richness, conservation efforts should be focused on the unmanaged Pico Alto region in the archipelago’s oldest island, Santa Maria

    Magnetoliposomes containing multicore nanoparticles and a new antitumor thienopyridine compound with potential application in chemo/thermotherapy

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    Multicore magnetic nanoparticles of manganese ferrite were prepared using carboxymethyl dextran as an agglutinating compound or by an innovative method using melamine as a cross-coupling agent. The nanoparticles prepared using melamine exhibited a flower-shape structure, a saturation magnetization of 6.16 emu/g and good capabilities for magnetic hyperthermia, with a specific absorption rate (SAR) of 0.14 W/g. Magnetoliposome-like structures containing the multicore nanoparticles were prepared, and their bilayer structure was confirmed by FRET (Förster Resonance Energy Transfer) assays. The nanosystems exhibited sizes in the range of 250–400 nm and a low polydispersity index. A new antitumor thienopyridine derivative, 7-[4-(pyridin-2-yl)-1H-1,2,3-triazol-1-yl]thieno[3,2-b]pyridine, active against HeLa (cervical carcinoma), MCF-7 (breast adenocarcinoma), NCI-H460 (non-small-cell lung carcino-ma) and HepG2 (hepatocellular carcinoma) cell lines, was loaded in these nanocarriers, obtaining a high encapsulation efficiency of 98% ± 2.6%. The results indicate that the new magnetoliposomes can be suitable for dual cancer therapy (combined magnetic hyperthermia and chemotherapy).This research was funded by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding of CF-UM-UP (UIDB/04650/2020) and through the research project PTDC/QUI-QFI/28020/2017 (POCI-01-0145-FEDER-028020), financed by the European Fund of Regional Development (FEDER), COMPETE2020, and Portugal2020. J.M.R. acknowledges FCT, ESF (European Social Fund—North Portugal Regional Operational Program) and HCOP (Human Capital Operational Program) for a PhD grant (SFRH/BD/115844/2016)
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