Conjugated linoleic acid reduces permeability and fluidity of adipose plasma membranes from obese Zucker rats

NOTICE: this is the author’s version of a work that was accepted for publication in Biochemical and Biophysical Research Communications. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Biochemical and Biophysical Research Communications. July 2010; 398 (2): 199-204.Conjugated linoleic acid (CLA) is a dietary fatty acid frequently used as a body fat reducing agent whose effects upon cell membranes and cellular function remain unknown. Obese Zucker rats were fed atherogenic diets containing saturated fats of vegetable or animal origin with or without 1% CLA, as a mixture of cis(c)9,trans(t)11 and t10,c12 isomers. Plasma membrane vesicles obtained from visceral adi- pose tissue were used to assess the effectiveness of dietary fat and CLA membrane incorporation and its outcome on fluidity and permeability to water and glycerol. A significant decrease in adipose membrane fluidity was correlated with the changes observed in permeability, which seem to be caused by the incor- poration of the t10,c12 CLA isomer into membrane phospholipids. These results indicate that CLA supple- mentation in obese Zucker rats fed saturated and cholesterol rich diets reduces the fluidity and permeability of adipose membranes, therefore not supporting CLA as a body fat reducing agent through membrane fluidification in obese fat consumers

Attack intensity of Corythucha ciliata (Hemiptera, Tingidae) on Platanus spp. in an urban area in Portugal: a comparison between pruned and unpruned trees.

Corythucha ciliata (Say, 1832), commonly known as sycamore lace bug (SLB), is an insect species native to North America. Since its accidental introduction in Europe (through Italy) in 1964, it has expanded across most European countries. The arrival of SLB in Portugal is uncertain but its distribution is wide. Sycamore (Platanus spp.), the only host of SLB, is one of the most widespread and important urban tree species in Portugal. It provides a wide range of environmental, social and economical benefits, which have been threatened by the invasion of this pest. SLB damages trees by feeding on the underside of the leaves causing discoloration and eventually premature senescence. While the long-term effect of SLB on the health of urban trees is yet to be fully assessed, there is compelling evidence that pruning further increases SLB damage. In this study we assessed the impact of pruning on the attack intensity of SLB. To test the hypothesis that pruning promotes the invasion of SLB, we compared the intensity of attack of pruned trees with unpruned trees. We collected sycamore leaves from pruned and unpruned trees and then assessed the intensity of attack by scaling damage by visual rating. Our findings show that pruned trees exhibit significantly higher attack intensities than unpruned trees (p < 0,001, χ2 goodness of fit). Based on these findings we recommend that sycamore pruning should be performed with caution (or even ceased), especially in urban areas where SLB is present

Pretreatments applied to microalgae residues to enhance anaerobic digestion

ABSTRACT: Biomass of microalga Chlorella protothecoides, grown under autotrophic and heterotrophic conditions and subjected to pretreatments, were energetically valorized through anaerobic digestion process according to the substrates: autotrophic algae (A), heterotrophic algae (H), heterotrophic algae extracted (HE), autoclave pretreated heterotrophic algae (HPA), enzyme pretreated heterotrophic algae (HPE), ultrasound pretreated heterotrophic algae (HPU), and inoculum (I). Despite the application of pretreatments, the highest methane production was obtained in the algae extracted digestion with 172 mL CH4, against 153, 126 and 142 mL obtained in HPA, HPE and HPU, respectively. The COD removal capacity was higher in the HPA sample while the TS and VS removal reached higher values in the autotrophic alga.N/

Effect of temperature on the bioactive properties of bee pollen

Bee pollen is flower pollen collected by the honey bee, Apis mellifera, for the purpose of feeding its larvae in the early stages of development. lt is recognized to be a valuable apitherapeutic product with potential for medical, health and nutritional applications. The objective of this work was to compares the effect of different storage conditions in the bioactive compounds and biological properties of bee pollen

Study of the electrochemical reduction of amoebicide Teclozan and its amperometric determination in pharmaceutical formulations

Neste trabalho, a redução eletroquímica do amebicida Teclozan (TEC) foi estudada sobre um eletrodo de carbono vítreo em meio de acetonitrila. Eletrólises com potencial controlado foram realizadas visando, tanto a determinação do número de elétrons envolvidos na redução do fármaco, quanto a identificação dos produtos eletrogerados, os quais foram isolados por extração líquido-líquido e caracterizados por 1H RMN. Foi verificado que o TEC apresenta dois picos voltamétricos, cada um associado à quebra redutiva de duas ligações C-Cl. Em presença de um doador de prótons, foi observado que o primeiro pico voltamétrico em −1,8 V corresponde principalmente à redução dos grupamentos -CHCl2 a -CH2Cl; enquanto o segundo pico em −2,2 V é responsável pela redução dos grupos -CH2Cl a CH3, fornecendo como único produto o derivado totalmente desalogenado do TEC, com rendimentos entre 82 e 97%. Este trabalho descreve também o desenvolvimento de um método eletroanalítico baseado na detecção amperométrica do TEC em condições hidrodinâmicas, o qual forneceu um limite de detecção de 8,9 × 10-6 mol L-1.The electrochemical reduction of amoebicide Teclozan (TEC) was studied on a glassy carbon electrode in acetonitrile. Controlled-potential electrolyses were performed for coulometric and preparative purposes. The electrogenerated products were isolated by liquid-liquid extraction and characterized by 1H NMR. It was observed that TEC presents two voltammetric peaks, each one associated with the cleavage of two C-Cl bonds. In presence of a proton donor it was observed that the first peak at −1.8 V promotes mainly the reduction of the groups CHCl2 to CH2Cl and the second one at −2.2 V promotes the reduction of the groups CH2Cl to CH3 giving as the sole product the completely dechlorinated TEC derivative with yields between 82 and 97%. In addition, a comparative study between the analytical performance of voltammetric techniques and amperometric detection of TEC in hydrodynamic conditions was performed. The amperometric detection was more sensitive than all evaluated voltammetric techniques, providing a detection limit of 8.9 × 10-6 mol L-1.FAPESP; CAPES; FC

A new method for testing antimicrobial activity of filamentous fungi

Tbls work was supporled by a FCT projecl (PTDC/AGR-AAM/099556/2008)

Biological invasion of Corythucha ciliata in green urban spaces in Portugal: a niche modeling approach using maximum entropy

Corythucha ciliata (Hemiptera: Tingidae) é um inseto nativo da América do Norte que foi introduzido na Europa, pela Itália, em 1964. Desde então tem se expandido por toda a Europa, desconhecendo-se a data de chegada e a sua área de distribuição em Portugal. Esta importante praga invasora alimenta-se na face inferior das folhas de plátano, uma das mais importantes árvores ornamentais nos espaços verdes urbanos em Portugal, causando senescência prematura e eventualmente morte, em casos de infestações severas consecutivas. A modelação de nicho está se tornando uma ferramenta cada vez mais importante na gestão de invasões biológicas, tanto antes como depois da introdução do organismo invasor. Neste estudo, o software MaxEnt (máxima entropia) foi usado na modelação da distribuição invasiva potencial de Corythucha ciliata em Portugal, a partir de um conjunto de variáveis ambientais e de dados de presença do inseto, obtidos a partir da observação de folhas de plátanos amostrados por todo o país. De acordo com o melhor modelo gerado pelo MaxEnt, as áreas de maior adequabilidade potencial à invasão de Corythucha ciliata encontram-se no norte de Portugal apresentando o sul e as regiões de maior altitude do norte e centro adequabilidade reduzida ou nula. Observações laboratoriais da biologia de Corythucha ciliata aliadas aos registos de ausência em várias localidades do sul de Portugal e ocorrência predominante na metade norte de Espanha suportam o modelo desenvolvido. Porém, a validação do modelo requer futuras prospecções nas áreas de reduzida adequabilidade e onde a praga se encontrava virtualmente ausente no momento em que foi realizada a amostragem. Os modelos de adequabilidade podem ser usados como ferramenta auxiliar na tomada de decisão no que concerne à gestão dos espaços verdes

Robô Lego & perturbações do espectro do autismo: uma potencial parceria?

Individuals with autism spectrum disorder (ASD) present difficulties in developing social behaviours, in communicating gestural or verbally, and they may present some repetitive motor activities. The objective of this study was to improve social competences and to enable the transfer of acquired skills of five children with ASD and intellectual disabilities using a low-cost Lego robot as a mediator. The proposed methodology was divided in five phases: Familiarization, Pre-test, Practice, Post-Test and Transfer of Skills. The study ran in two sequential periods at different places. Each of these periods tackled different individual research questions and goals (taking into account the target group). During each period, the proposed methodology had to be adjusted according to the current context. Therefore, different experimental scenarios and corresponding specific goals had to be delineated. Results show that joint attention of the children increased over the sessions; and interaction with the researcher was verified. Furthermore, results show that there was an effective transfer of skills in the addressed case studies. This reinforces conclusions that robots seem, in fact, powerful tools that should be explored concerning this target population. But a more detailed study is required. The proposed methodology can be used by professionals and parents as a complement to common interventions.A perturbação do espectro do autismo (PEA) caracteriza-se por dificuldades no desenvolvimento de comportamentos sociais, na comunicação verbal ou gestual, e pela manifestação de atividades motoras repetitivas. O objetivo deste estudo foi o de melhorar as competências sociais e a transferência das competências de cinco crianças com PEA e deficiência mental associada usando um robô de baixo custo da Lego como um mediador. A metodologia proposta foi dividida em cinco fases: familiarização, pré-teste, prática, pós-teste e transferência de competências. O estudo foi realizado em dois períodos sequenciais em diferentes lugares. Em cada período foram definidas diferentes questões de investigação tendo em conta o grupo-alvo. Os resultados mostram que a atenção conjunta e a interação com o investigador aumentaram ao longo das sessões. Além disso, os resultados indicam que houve uma transferência efetiva de competências nos estudos de caso abordados. Isso reforça as conclusões que o robô da Lego pode ser uma ferramenta adequada a ser explorada com esta população-alvo. No entanto, é necessário um estudo mais detalhado e com uma amostra maior. A metodologia proposta pode ser usada por profissionais e pais como complemento às intervenções tradicionais

Drought response of cowpea (Vigna unguiculata (L.) Walp.) landraces at leaf physiological and metabolite profile levels

Drought threatens the world’s food production, particularly in Sub Saharan Africa low external input and rain fed agricultural systems, where cowpea (Vigna unguiculata (L.) Walp.) is an important food crop. In the context of growing concerns regarding climate changes implications on water availability, this study aimed at 1) to evaluate the drought responses in cowpea landraces with contrasting drought tolerance levels (A55 – high sensitivity; A80 - mild sensitivity; A116 - tolerant), 2) using an integrated physiological (leaf gas exchanges; chlorophyll a fluorescence) and biochemical (photoprotective pigments; RuBisCO activity; primary metabolite profiling) analysis to identify drought tolerance probes, in plants submitted to three water availability levels (well-watered, WW; mild drought, MD; severe drought, SD). A116 plants maintained a better water status under drought, what could justify the higher Pn and Pnmax values in MD, as well as higher photochemical use of energy (reflected in the photochemical quenching (qL) and in the quantum yield of non-cyclic electron transport (Y(II))), and the lower need of photoprotective thermal dissipation mechanisms (given by the non-photochemical quenching (qN), and the quantum yield of regulated energy dissipation at photosystem PSII (Y(NPQ))), in MD and SD plants. Greater declines of net (Pn) and potential (Pnmax) photosynthesis were observed in A55 plants, which frequently showed significant impacts already under MD conditions in most parameters, whereas A80 usually displayed and intermediate behaviour. Still, even A55 showed some acclimation response, regarding photoprotective mechanisms associated with high contents of zeaxanthin, lutein, and carotenes, and high Y(NPQ), and qN values, supporting the absence of an increase in the non-regulated energy dissipation at PSII (Y(NO) did not increased) even in SD plants. Additionally, A55 was not significantly affected in RuBisCO activity, which showed to be quite resilient in cowpea. A primary metabolite profiling, complemented with a partial least square discrimination analysis (PLS-DA), allowed a better separation of A116 and A55 plants according to their degree of drought tolerance. In response to drought, A116 showed the greatest accumulation of most responsive metabolites, 14 in total, with sucrose, fucose, urea, alanine and putrescine being exclusively increased in this genotype, suggesting that they can be candidates as drought tolerance proxies. Other compounds, as proline, valine, isoleucine (among amino acids), and rhamnose and raffinose (among sugars) showed close increase patternsinfo:eu-repo/semantics/publishedVersio

Physical activity, physical fitness and metabolic risk factors in Azorean adolescents

This study aimed to analyze the relationships between metabolic risk factors (MRF) with physical activity (PA) and physical fitness (PF) in a sample of Azorean adolescents.info:eu-repo/semantics/publishedVersio