Multivalent enzymes that enable the use of hydrogen peroxide for microaerobic and anaerobic proliferation

This work was financed by national funds from FCT - Fundação para a Ciência e a Tecnologia, I.P., in the scope of the project UIDP/04378/2020 and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences - UCIBIO and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy - i4HB. FCT supported SRP through the projects PTDC/BIA-PRO/109796/2009 and PTDC/BIA-BQM/29442/2017, DSB and RNSO through the scholarships UI/BD/151168/2021, and “Verão com Ciência2020”, respectively.Bacterial peroxidases are responsible for the reduction of hydrogen peroxide to water. Found in the periplasm of gram-negative bacteria, they are one of the defense mechanisms against endogenous and exogenous peroxide stress under low oxygen tensions. Besides being involved in peroxide detoxification, bacterial peroxidases have been proposed to constitute an alternative pathway to the respiratory chain under anoxic conditions, as demonstrated in E. coli that can use hydrogen peroxide as an electron acceptor in the absence of oxygen. Bacterial peroxidases are c-type cytochromes with either two or three c-type hemes bound to the polypeptide chain, being divided into classical or non-classical, respectively. Orthologous to the classical bacterial peroxidases are the MauG enzymes that share some structural, spectroscopic and sequence similarities but have distinct physiological roles (though for most their function remains unknown). The spectroscopic and kinetic data on bacterial peroxidases are reviewed for both classes. Most classical bacterial peroxidases require reductive activation that consists in structural changes so that the catalytic heme becomes accessible to the substrate. However, non-classical enzymes are ready to bind the hydrogen peroxide as their catalytic center is penta-coordinated, which is also observed in their structural model. The few studies that report the involvement of bacterial peroxidases from pathogenic bacteria in biofilms, is an indication that these enzymes might contribute to their infection mechanism and thus can constitute alternative drug targetspublishersversionpublishe

Viabilidade econômica da integração lavoura-pecuária.

O objetivo deste trabalho foi avaliar a viabilidade econômica da integração lavoura-pecuária em áreas irrigadas no Estado de Goiás

A proteomic study to identify soya allergens - the human response to transgenic versus non-transgenic soya samples

BACKGROUND: In spite of being among the main foods responsible for allergic reactions worldwide, soybean (Glycine max)-derived products continue to be increasingly widespread in a variety of food products due to their well-documented health benefits. Soybean also continues to be one of the elected target crops for genetic modification. The aim of this study was to characterize the soya proteome and, specifically, IgE-reactive proteins as well as to compare the IgE response in soya-allergic individuals to genetically modified Roundup Ready soya versus its non-transgenic control. METHODS: We performed two-dimensional gel electrophoresis of protein extracts from a 5% genetically modified Roundup Ready flour sample and its non-transgenic control followed by Western blotting with plasma from 5 soya-sensitive individuals. We used peptide tandem mass spectrometry to identify soya proteins (55 protein matches), specifically IgE-binding ones, and to evaluate differences between transgenic and non-transgenic samples. RESULTS: We identified 2 new potential soybean allergens--one is maturation associated and seems to be part of the late embryogenesis abundant proteins group and the other is a cysteine proteinase inhibitor. None of the individuals tested reacted differentially to the transgenic versus non-transgenic samples under study. CONCLUSION: Soybean endogenous allergen expression does not seem to be altered after genetic modification. Proteomics should be considered a powerful tool for functional characterization of plants and for food safety assessment

Rainfall-triggered landslides in the Lisbon region over 2006 and relationships with the North Atlantic Oscillation

Landslides occurred in the Lisbon area during the last 50 years were almost always induced by rainfall and have been used to establish rainfall thresholds for regional landslide activity. In 2006, three new rainfall-triggered landslide events occurred in the study area, namely on the 20 March, the 25–27 October, and the 28 November. Landslide events occurred in March and October 2006 include shallow translational slides and few debris flows, and the corresponding absolute antecedent rainfall was found to be above the threshold for durations ranging from 4 to 10 days. These events also fit the combined threshold of daily precipitation and 5 days calibrated antecedent rainfall values. Likewise the landslide event that took place in late November 2006 includes some slope movements with deeper slip surfaces, when compared with landslides dating from March and October. Moreover, the corresponding absolute antecedent rainfall was also found to be above the 40-day period rainfall threshold. Here we characterize in detail the short and long-term atmospheric circulation conditions that were responsible for the intense rainfall episodes that have triggered the corresponding landslide events. It is shown that the three rainfall episodes correspond to considerably different synoptic atmospheric patterns, with the March episode being associated to an intense cut-off low system while the October and November episodes appear to be related to more typical Atlantic low pressure systems (and associated fronts) travelling eastwards. Finally, we analyse the role played by the North Atlantic Oscillation (NAO) during those months marked by landslide activity. It is shown that the NAO index was consistently negative (usually associated with above average precipitation) for the months prior to the landslide events, i.e. between October 2005 and March 2006, and again between August and October 2006.info:eu-repo/semantics/publishedVersio

Morphological transition of Helicobacter pylori adapted to water

To view the supplementary data that accompany this paper please visit the journal website at: www. futuremedicine.com /doi/full/10.2217/fmb-2016-0174.Aim: This study aims to investigate the morphological transition of Helicobacter pylori during adaptation to water. Materials \& methods: Different strains were adapted to water. Changes regarding cultivability and cellular morphology were recorded. Expression of 11 genes involved in H. pylori morphological changes was evaluated by real-time PCR. Results: H. pylori presented increased cultivability in water after adaptation. The permanent loss of the spiral shape was observed, but no transition into coccoid form has occurred. Expression levels of genes involved in peptidoglycan assembly of H. pylori 26695 have shown significant changes between adapted and nonadapted strains. Conclusion: Adaption to water favors the culturable phenotype and the morphological transition to the rod shape, into a process that implicates the peptidoglycan turnover.This work was supported by the Portuguese Foundation for Science and Technology (FCT) under the project ‘Heliwater’ (PTDC/BIA-MIC/108811/2008), the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 – Programa Operacional Regional do Norte. No writing assistance was utilized in the production of this manuscript.info:eu-repo/semantics/publishedVersio

Steroselective synthesis of imidazolidin-4-ones from α-amino amides of the antimalarial primaquine and substituted benzaldehydes

Imidazolidin-4-ones are commonly employed as skeletal modifications in bioactive oligopeptides, either as proline surrogates or for protection of the N-terminal amino acid against aminopeptidase-catalysed hydrolysis . We have been working on the synthesis of imidazolidin-4-ones of the antimalarial primaquine , through acylation of primaquine with an α-amino acid and subsequent reaction of the resulting α-aminoamide with a ketone or aldehyde. Thus, when using racemic primaquine, an optically pure chiral α-amino acid and an aldehyde as starting materials, four imidazolidin-4-one diastereomers are to be expected (Scheme 1). However, we have recently observed that imidazolidin-4-one synthesis was stereoselective when 2-carboxybenzaldehyde (2CBA)* was used, as only two diastereomers were produced2. Computational studies have shown that the imine formed prior to ring closure had, for structures derived from 2CBA, a quasi-cyclic rigid structure2. This rigid conformation is stabilized by an intramolecular hydrogen bond involving the C=O oxygen atom of the 2-carboxyl substituent in 2CBA and the N-H group of the α-amino amide moiety2. These findings led us to postulate that the 2-carbonyl substituent in the benzaldehyde moiety was the key for the stereoselective synthesis of the imidazolidin-4-ones2

Chemical and Sensorial Characterization of Tropical Syrah Wines Produced at Different Altitudes in Northeast of Brazil

Over the years, viticulture has expanded to new regions outside the temperate zones, such as Northeast Brazil, India, Thailand, Myanmar, Vietnam, Bangladesh and Venezuela, characterized by the production of tropical wines. It is important for the productive sector to comprehend the effects of grapevine interaction with the characteristics of each new region on wines composition. In this study, the composition of wines of Syrah from two regions with different altitudes in Northeast Brazil were analyzed by different methodologies to characterize chemical compounds as sugar, acids, minerals, phenolics (anthocyanins, flavonols, stilbenes and condensed tannins) and the sensory profile. The wines of the Bahia region (1100 m of altitude) obtained high concentrations for chemical parameters related to color, monomeric anthocyanins, stilbenes and monomeric and oligomeric tannins. Wines of the low altitude region, Pernambuco (350 m of altitude) were characterized by higher concentrations of flavonols (kaempferol, isorhamnetin, quercetin and rutin) and polymerized tannins. The chemical composition of wines from the two studied regions was influenced by altitude. A trend towards higher concentrations in most for phenolic compounds analyzed was observed in wines from the higher altitude region during the two years of study. Regarding the sensory profile, fruity, floral, herbaceous and empyreumatic attributes aromatic obtained highest scores in wines of the 350 m altitude region, the other attributes were dependent on the year of harvest

Linearity evaluation of analytical methods of radiopharmaceutical fluorodeoxyglucose-18

Radiofármacos são medicamentos utilizados na Medicina Nuclear para avaliar funções biológicas e patofisiológicas, realizar estudos do funcionamento do cérebro e diversas outras enfermidades, assim comodesenvolver uma terapia eficaz. Tomografia por emissão de pósitron e tomografia computadorizada por emissão de fóton único são alguns dos métodos que utilizam radiofármacos. Desenvolvimento de novos radiofármacos é a solução para a análise in vivo de imagens endógenas. Contudo não só o desenvolvimento é importante. A qualidade e o comportamento do radiofármaco desenvolvido devem ser comprovadas , diariamente. Nesse trabalho os autores avaliam a metodologia de determinação de etanol e do teor de F-18 e FDG-18 como forma de avaliação da qualidade do produto final, e dos método utilizados, assim como dos equipamentos. Os resultados revelam que a metodologia de determinação de etanol em solução de FDG-18 deve ser revista. Contudo a análise de teor de F-18 e FDG-18, mostrou-se bastante eficaz.Radiopharmaceuticals are drugs used in Nuclear Medicine to measure physiological and biological functions, to evaluate higher brain function, to study the pathophysiology of various disorders and to develop effective therapy. Positron emission tomography (PET) and single-photon emission computed tomography are representative molecular imaging methods. Development of radiopharmaceuticals is a key for successful in vivo imaging. However, not only the development of new radiopharmaceuticals are important. The quality and behavior of this radiopharmaceuticals must be improved daily. In this manuscript, the authors introduces experiences and concepts for development of quality control test to be used in the routine of radiopharmaceuticals industry, in order to verify the quality of the method and the quality of the final product (radiopharmaceuticals) produced. The results showed that an alternative methods for quantification of ethanol is required. Despite of the results of the linearity, the quantification of content of radiopharmaceuticals (F-18 and FDG-18) shown to be satisfactory.Colegio de Farmacéuticos de la Provincia de Buenos Aire

The influence of surface modified poly(L-lactic acid) films on the differentiation of human monocytes into macrophages

Macrophages play a crucial role in the biological performance of biomaterials, as key factors in defining the optimal inflammation-healing balance towards tissue regeneration and implant integration. Here, we investigate how different surface modifications performed on poly(L-lactic acid) (PLLA) films would influence the differentiation of human monocytes into macrophages. We tested PLLA films without modification, surface-modified by plasma treatment (pPLLA) or by combining plasma treatment with different coating materials, namely poly(L-lysine) and a series of proteins from the extracellular matrix: collagen I, fibronectin, vitronectin, laminin and albumin. While all the tested films are non-cytotoxic, differences in cell adhesion and morphology are observed. Monocyte-derived macrophages (MDM) present a more rounded shape in non-modified films, while a more elongated phenotype is observed containing filopodia-like and podosome-like structures in all modified films. No major differences are found for the expression of HLA-DR+/CD80(+) and CD206(+)/CD163(+) surface markers, as well as for the ability of MDM to phagocytize. Interestingly, MDM differentiated on pPLLA present the highest expression of MMP9. Upon differentiation, MDM in all surface modified films present lower amounts of IL-6 and IL-10 compared to non-modified films. After stimulating MDM with the potent pro-inflammatory agent LPS, pPLLA and poly(L-lysine) and fibronectin-modified films reveal a significant reduction in IL-6 secretion, while the opposite effect is observed with IL-10. Of note, in comparison to non-modified films, all surface modified films induce a significant reduction of the IL-6/IL-10 ratio, a valuable prognosticator of the pro-versus anti-inflammatory balance. These findings provide important insights into MDM-biomaterial interactions, while strengthening the need for designing immune-informed biomaterials.project NORTE-01-0145-FEDER-000023, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement through the European Regional Development Fund (FEDER). C. R. Correia and J. F. Mano acknowledge the funding from the European Research Council for project ATLAS with the grant agreement number ERC-2014-ADG-669858. J. Gaifem, M.B. Oliveira and R. Silvestre acknowledge the Portuguese Foundation for Science and Technology (FCT) for the doctoral (PD/BD/106053/2015), post-doctoral (SFRH/BPD/111354/2015) and FCT Investigator (IF/00021/2014) grants, respectively. The authors also acknowledge Hospital de Braga for providing the buffy coatsThis work was developed under the scope of the project NORTE-01-0145-FEDER-000023, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement through the European Regional Development Fund (FEDER). C. R. Correia and J. F. Mano acknowledge the funding from the European Research Council for project ATLAS with the grant agreement number ERC-2014-ADG-669858. J. Gaifem, M.B. Oliveira and R. Silvestre acknowledge the Portuguese Foundation for Science and Technology (FCT) for the doctoral (PD/BD/106053/2015), post-doctoral (SFRH/BPD/111354/2015) and FCT Investigator (IF/00021/2014) grants, respectively. The authors also acknowledge Hospital de Braga for providing the buffy coats.info:eu-repo/semantics/publishedVersio

Data-driven inference for the spatial scan statistic

<p>Abstract</p> <p>Background</p> <p>Kulldorff's spatial scan statistic for aggregated area maps searches for clusters of cases without specifying their size (number of areas) or geographic location in advance. Their statistical significance is tested while adjusting for the multiple testing inherent in such a procedure. However, as is shown in this work, this adjustment is not done in an even manner for all possible cluster sizes.</p> <p>Results</p> <p>A modification is proposed to the usual inference test of the spatial scan statistic, incorporating additional information about the size of the most likely cluster found. A new interpretation of the results of the spatial scan statistic is done, posing a modified inference question: what is the probability that the null hypothesis is rejected for the original observed cases map with a most likely cluster of size k, taking into account only those most likely clusters of size k found under null hypothesis for comparison? This question is especially important when the p-value computed by the usual inference process is near the alpha significance level, regarding the correctness of the decision based in this inference.</p> <p>Conclusions</p> <p>A practical procedure is provided to make more accurate inferences about the most likely cluster found by the spatial scan statistic.</p