Flow behaviour in microchannels of an innovative blood analogue fluid based on giant unilamellar vesicles

This work focused on the development of an innovative blood analogue, containing giant unilamellar vesicles (GUVs), to mimic the flow behaviour of red blood cells (RBCs). The rheological characterization of different blood analogue solutions was performed in a stress controlled rheometer and the results have shown a good agreement when compared with a sample containing 5% of RBCs.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2013. The authors also acknowledge the financial support provided by FCT through the project PTDC/QEQ-FTT/4287/2014.info:eu-repo/semantics/publishedVersio

Dithiocarbamate residues in fruits and leaves of passion fruit (Passiflora edulis) from different Brazilian regions

Dithiocarbamates are widely used fungicides, including in passion fruit, whose fruits are mainly used for juice production, the leaves for the preparation of herbal tea and medicines. Also, the use of the peel in the food industry has been proposed. In this study, the spectrophotometric method for determination of dithiocarbamate residues, as CS2, in passion fruit (Passiflora edulis) was validated at a limit of quantification (LOQ) of 0.05 mg kg-1 CS2, and 108 samples (55 fruits and 53 leaves) collected from Brazilian growers were analyzed. About 25% of the fruit peel samples were positive (0.06 to 1.4 mg kg-1) and only one sample had residues in the pulp (0.09 mg kg-1), 43.4% of leaf samples contained residues. Washing of fruit reduced the residues in the peel by up to 100%, and drying the leaves increased residue levels by up to 60%. This is the first study that reports dithiocarbamate residues in passion fruit in Brazil, and the results are important for government authorities when planning monitoring programs, and for food and herbal medicine industries

Microfluidic deformability study of an innovative blood analogue fluid based on giant unilamellar vesicles

Blood analogues have long been a topic of interest in biofluid mechanics due to the safety and ethical issues involved in the collection and handling of blood samples. Although the current blood analogue fluids can adequately mimic the rheological properties of blood from a macroscopic point of view, at the microscopic level blood analogues need further development and improvement. In this work, an innovative blood analogue containing giant unilamellar vesicles (GUVs) was developed to mimic the flow behavior of red blood cells (RBCs). A natural lipid mixture, soybean lecithin, was used for the GUVs preparation, and three different lipid concentrations were tested (1 × 10−3 M, 2 × 10−3 M and 4 × 10−3 M). GUV solutions were prepared by thin film hydration with a buffer, followed by extrusion. It was found that GUVs present diameters between 5 and 7 µm which are close to the size of human RBCs. Experimental flow studies of three different GUV solutions were performed in a hyperbolic-shaped microchannel in order to measure the GUVs deformability when subjected to a homogeneous extensional flow. The result of the deformation index (DI) of the GUVs was about 0.5, which is in good agreement with the human RBC’s DI. Hence, the GUVs developed in this study are a promising way to mimic the mechanical properties of the RBCs and to further develop particulate blood analogues with flow properties closer to those of real blood.COMPETE2020, NORTE2020, PORTUGAL2020, FEDER; FCT Project PTDC/QEQ-FTT/4287/2014 (POCI-01-0145-FEDER-016861); FCT Project PTDC/EMD-EMD/29394/2017 (NORTE-01-0145-FEDER-029394); FCT Project PTDC/EME-SIS/30171/2017 (NORTE-01-0145-FEDER-000032); FCT Project PTDC/QUI-QFI/28020/2017 (POCI-01-0145-FEDER-028020); SFRH/BD/99696/2014 PhD Grant;info:eu-repo/semantics/publishedVersio

Banana peel and grape stalk: potential of valorization through the evaluation of chemical composition and physical-chemical properties

CHISA 2008 - 18th International Congress of Chemical and Process Engineering (CD-ROM of Full Texts)Bioconversion of food processing residues (agr o-based industrial residues) in valuable products has been receiving an increasing attention in the last years. In fact, the main problem experienced by agro-based industries in several c ountries is the management of their residues. As a consequence, many research centers and government departments are preparing scientific strategies in order to develop biotechnological processes capable of transforming these residues in new bio-products or as sources of other chemicals. Most of these agro-industrial residues are lignocellulosic materials constituted basically of cellulose, hemicelluloses, and lignin. In particular, banana production is one of the main economic resources of several regions in many countries, an important crop in the tropical and sub- tropical regions and one of the most consumed fruits in the world. Grapes are other of the world’s largest fruit crops, mainly grown for direct consumption, grape juice and wine- making processes. These agricultural/industrial activities generate large amounts of residues such as banana fruit peel and grape stalk. Taking in consideration these facts, it is fundamental to know their chemical composition and physical-chemical properties, in order to evaluate perspectives of applications and improvement of procedures towards an efficient utilization of these residues. For this reason, following hydrolysis, the residues obtained were analyzed by HPLC, FTIR, TGA and DSC. Preliminary results indicate the attractiveness of these materials for further applications due to their chemical composition and physical-chemical properties: glucan and xylan contents of banana peel are 23.2 ± 0.2% and 18.9 ± 0.5%, respectively, while grape stalk contains 26.5 ± 1.5% and 16.8 ± 0.4%, respectively. These results are in agreement with those obtained with some other agro-industrial residues. These approaches offer several advantages, since the several fractions obtained from the hydrolysis of these annually produced materials can be applied as raw-materials to reduce the existence of environmentally hazardous situations and/or to increase the supply of energy or chemicals produced from renewable resourcesFCT(Portugal), FAPESP(Brazil) and CAPES/GRICES(Brazil/Portugal)info:eu-repo/semantics/publishedVersio

When an Intramolecular Disulfide Bridge Governs the Interaction of DUOX2 with Its Partner DUOXA2

Aims: The dual oxidase 2 (DUOX2) protein belongs to the NADPH oxidase (NOX) family. As H2O2 generator, it plays a key role in both thyroid hormone biosynthesis and innate immunity. DUOX2 forms with its maturation factor, DUOX activator 2 (DUOXA2), a stable complex at the cell surface that is crucial for the H2O2-generating activity, but the nature of their interaction is unknown. The contribution of some cysteine residues located in the N-terminal ectodomain of DUOX2 in a surface protein?protein interaction is suggested. We have investigated the involvement of different cysteine residues in the formation of covalent bonds that could be of critical importance for the function of the complex. Results: We report the identification and the characterization of an intramolecular disulfide bond between cys-124 of the N-terminal ectodomain and cys-1162 of an extracellular loop of DUOX2, which has important functional implications in both export and activity of DUOX2. This intramolecular bridge provides structural support for the formation of interdisulfide bridges between the N-terminal domain of DUOX2 and the two extracellular loops of its partner, DUOXA2. Innovation: Both stability and function of the maturation factor, DUOXA2, are dependent on the oxidative folding of DUOX2, indicating that DUOX2 displays a chaperone-like function with respect to its partner. Conclusions: The oxidative folding of DUOX2 that takes place in the endoplasmic reticulum (ER) appears to be a key event in the trafficking of the DUOX2/DUOXA2 complex as it promotes an appropriate conformation of the N-terminal region, which is propitious to subsequent covalent interactions with the maturation factor, DUOXA2. Antioxid. Redox Signal. 23, 724?733.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140308/1/ars.2015.6265.pd

Rodas de diálogos: construindo a agroecologia do DF e Entorno

Em outubro de 2014 ocorreu o IV Seminário de Agroecologia do Distrito Federal e Entorno, no Centro de Convenções Ulysses Guimarães, em Brasília – DF. O seminario reuniu cerca de 1.200 participantes entre agricultores/as, extensionistas, pesquisadores/as, professores/as, gestores/as públicos, estudantes, representantes de movimentos sociais e sindicais, para discutir os temas de agricultura familiar e políticas públicas no contexto da Agroecologia. O presente trabalho se propõe a relatar o desenvolvimento e resultados da dinâmica “Rodas de Diálogos: Construindo a Agroecologia do DF e Entorno”, realizada no âmbito do seminário. A partir dessa dinâmica, foi possível sistematizar as opiniões dos participantes sobre a Agroecologia no DF relacionada ao futuro ideal, situação presente e, em como como chegar ao futuro ideal. As Rodas de Diálogos contaram com grande integração dos, aproximadamente, 400 participantes, para compreender de forma colaborativa o cenário da Agroecologia na região e projetar estrategicamente um cenário futuro ideal, a partir de tudo que foi visto no seminario, que se encaixam em categorias específicas: Articulação; Educação; Meio Ambiente; Mercado; Políticas Públicas.Eje: B5 Sistemas de conocimiento (Relatos de experiencias)Facultad de Ciencias Agrarias y Forestale

Indole-Containing Pyrazino[2,1-b]quinazoline-3,6-diones Active against Plasmodium and Trypanosomatids

The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acsmedchemlett.1c00589.Malaria, leishmaniasis, and sleeping sickness are potentially fatal diseases that represent a real health risk for more than 3,5 billion people. New antiparasitic compounds are urgent leading to a constant search for novel scaffolds. Herein, pyrazino[2,1-b]quinazoline-3,6-diones containing indole alkaloids were explored for their antiparasitic potential against Plasmodium falciparum, Trypanosoma brucei, and Leishmania infantum. The synthetic libraries furnished promising hit compounds that are species specific (7, 12) or with broad antiparasitic activity (8). Structure-activity relationships were more evident for Plasmodium with anti-isomers (1S,4R) possessing excellent antimalarial activity, while the presence of a substituent on the anthranilic acid moiety had a negative effect on the activity. Hit compounds against malaria did not inhibit β-hematin, and in silico studies predicted these molecules as possible inhibitors for prolyl-tRNA synthetase both from Plasmodium and Leishmania. These results disclosed a potential new chemotype for further optimization toward novel and affordable antiparasitic drugs.publishersversionpublishe

Outcomes of TB Treatment by HIV Status in National Recording Systems in Brazil, 2003–2008

BACKGROUND: Although the Brazilian national reporting system for tuberculosis cases (SINAN) has enormous potential to generate data for policy makers, formal assessments of treatment outcomes and other aspects of TB morbidity and mortality are not produced with enough depth and rigor. In particular, the effect of HIV status on these outcomes has not been fully explored, partly due to incomplete recording in the national database. METHODOLOGY/PRINCIPAL FINDINGS: In a retrospective cohort study, we assessed TB treatment outcomes, including rates of cure, default, mortality, transfer and multidrug resistant TB (MDR-TB) among a purposively chosen sample of 161,481 new cases reported in SINAN between 2003 and 2008. The study population included all new cases reported in the six States with the highest level of completeness of the HIV status field in the system. These cases were mostly male (67%), white (62%), had pulmonary TB (79%) and a suspect chest X ray (83%). Treatment outcomes were best for those HIV negative cases and worst for those known HIV positive patients (cure rate of 85.7% and 55.7% respectively). In multivariate modeling, the risk of having an unfavorable outcome (all outcomes except cure) was 3.09 times higher for those HIV positive compared with those HIV negative (95% CI 3.02-3.16). The risk of death and default also increased with HIV positivity. The group without a known HIV status showed intermediate outcomes between the groups above, suggesting that this group includes some with HIV infection. CONCLUSIONS: HIV status played an important role in TB treatment outcomes in the study period. The outcomes observed in those with known HIV were poor and need to be improved. Those in the group with unknown HIV status indicate the need for wider HIV testing among new TB cases