Nanoparticles as a tool in capillary electrochromatography

Two different types of molecularly imprinted nanoparticles against (R)-propranolol were used to separate the enantiomers of propranolol in capillary electrochromatography mode, methacrylic acid based nanoparticles and core-shell molecularly imprinted polymer nanoparticles. Partial filling technique was used to avoid interference of molecularly imprinted polymer nanoparticles in UV detection. With methacrylic acid based nanoparticles it was not possible to obtain enantiomer separation. Strong unspecific interactions between the molecular imprinted polymer nanoparticles and propranolol disturbed enantiomer separation. Since large content of acetonitrile had to be used in order to obtain stable suspensions of molecularly imprinted polymer nanoparticles, the electrostatic interactions were favored which contributed to the unspecific interactions occurring. Core-shell molecularly imprinted polymer nanoparticles present suspension stability at low content of acetonitrile due to the poly(acrylamide) shell that makes them more hydrophilic. Enantiomer separation of propranolol was achieved with 40% of acetonitrile. Reproducibility was problematic due to the unspecific interactions occurring. With time several factors can occur contributing to the decreased reproducibility of results such as, interactions between the molecularly imprinted polymer nanoparticles and the capillary wall or evaporation of the organic solvent due to the design of vials used in capillary electrochromatography system. The core-shell molecularly imprinted polymer nanoparticles are more suitable for propranolol enantiomer separation in comparison to methacrylic acid based nanoparticles. More stable suspensions give a greater range of conditions that can be tested. Silanized gadolinium oxide nanoparticles were tested as pseudostationary phase in capillary electrochromatography for protein separation. The lack of interference with UV detection and the large surface area of these nanoparticles make them a promising tool in capillary electrochromatography for protein separation. These nanoparticles interact with the proteins that are analyzed. Increased injection times of the nanoparticles give retained peaks of human growth hormone showing that strong interactions between the protein and nanoparticles are occurring. Lysozyme that was not recovered using conventional capillary electrophoresis could be detected when nanoparticles were used as pseudostationary phase. The nanoparticles can act as a coating in the capillary wall or due to their large surface area they can prevent adsorption of the lysozyme to the capillary.Dois tipos diferentes de nanopartículas impressas molecularmente, selectivas de (R) – propranolol, foram utilizadas para a separação dos enantiomeros de propranolol em electrocromatografia capilar ( nanopartículas à base de ácido metacrílico e nanopartículas revestidas com poliacrilamida). Para evitar interferência das nanopartículas com a detecção UV a técnica de preenchimento parcial foi utilizada. Com as nanopartículas à base de ácido metacrílico a separação dos enantiomeros de propranolol não foi alcançada. Interacções fortes inespecíficas entre as nanopartículas e o propronolol impossibilitaram a separação. Para obter suspensões estáveis de nanopartículas à base de ácido metacrílico elevadas quantidades de acetonitrilo foram utilizadas, favorecendo interacções eletrostáticas que contribuiram para o aumento das interacções inespecíficas. As nanopartículas revestidas com poliacrilamida apresentam suspensões estáveis com baixas quantidades de acetonitrilo, devido as propriedades hidrofílicas da poliacrilamida. A separação dos enantiomeros de propranolol foi alcançada com 40% de acetonitrilo. As interacções inespecíficas foram um factor dominante na irreproducibilidade dos resultados. Com o tempo vários factores contribuem para a diminuição da reproducibilidade dos resultados como por exemplo: interacções entre as nanopartículas e a parede do capilar e a evaporação do solvente orgânico devido ao design dos tubos de ensaio utilizados na electrocromatografia capilar. As nanopartículas revestidas com poliacrilamida säo mais adequadas para a separação dos enantiomeros de propranolol devido á elevada estabilidade de suspensöes apresentada em diferentes condições. Nanopartículas de gadolínio silanizadas foram testadas como fase pseudoestacionária em electrocromatografia capilar. Características como a não detecção em UV e a grande área de superfície tornam estas nanopartículas de grande interesse para a separação de proteínas. A hormona de crescimento e a lisozima foram as proteínas analisadas. A hormona de crescimento apresenta picos mais retidos quando se aumenta os tempos de injecção das nanopartículas, mostrando que interacções entre a proteína e as nanopartículas ocorrem. A utilização destas nanopartículas como fase pseudoestacionária permitiu a detecção da lisozima que não é visível utilizando electroforese capilar convencional. A adsorção da lisozima à parede do capilar é evitada devido ao uso destas nanopartículas

Propriedades tecnológicas e probióticas das bactérias isoladas do queijo do Pico

A secção Biologia é coordenada pelo Professor Universitário Armindo Rodrigues.[…]. A listéria é o agente patogénico responsável pela listeriose, uma infeção rara, mas grave nos seres humanos. Leite e produtos lácteos têm sido implicados na maioria dos surtos relatados de listeriose, embora o tratamento térmico elimine esta bactéria durante o processo de pasteurização. Isto indica que estes produtos podem ser contaminados em fases posteriores de produção. Desta forma, a contaminação do queijo com listéria é um problema recorrente e uma preocupação constante para a indústria dos lacticínios. A utilização de bactérias que possam combater este agente patogénico pode ser uma mais-valia na aplicação a este tipo de produtos. Assim, um dos grandes objetivos consiste em identificar novas estirpes com atividade antimicrobiana para utilização na produção de queijos mais seguros e de melhor qualidade. […].info:eu-repo/semantics/publishedVersio

Managers’ individual values and performance

The paper presents a study in the field of organizational behavior concerning individual values and self-reported performance of intermediate leaders. Its main objective was to identify priority values, specially the hierarchy of values according to the intermediate leaders' personal priorities and link them to job performance using exploratory and descriptive methodology, through a survey, scaled with questionnaires "SVS individual values" and “selfreported performance,” both through Likert scale and deductive logic. It was made a census with leaders in intermediate leadership positions in a medium-sized food industry in the state of Ceará - Brazil. Data were collected electronically and analyzed by SPSS software, using descriptive and factorial statistics. The results pointed to the priority values of motivational types "Benevolence" associated with Compliance. Those with better self-reported performance presented a different result: Benevolence was associated with Self-determination. The overall objective was achieved because the priority values were identified in the intermediate leadership and they were related to professional performance, otherwise checking which values are on top for leaders with better self-reported performance. The study brought new contributions in the area of Organizational Behavior, particularly in what concerns organizational management, the importance of the intermediate leaders in the context of organizational leadership, the understanding of their values, performance, as well astheir motivation

Antibiotic free selection for the high level biosynthesis of a silk-elastin-like protein

Silk-elastin-like proteins (SELPs) are a family of genetically engineered recombinant protein polymers exhibiting mechanical and biological properties suited for a wide range of applications in the biomedicine and materials fields. They are being explored as the next generation of biomaterials but low productivities and use of antibiotics during production undermine their economic viability and safety. We have developed an industrially relevant, scalable, fed-batch process for the high level production of a novel SELP in E. coli in which the commonly used antibiotic selection marker of the expression vector is exchanged for a post segregational suicide system, the separate-component-stabilisation system (SCS). SCS significantly augments SELP productivity but also enhances the product safety profile and reduces process costs by eliminating the use of antibiotics. Plasmid content increased following induction but no significant differences in plasmid levels were discerned when using SCS or the antibiotic selection markers under the controlled fed-batch conditions employed. It is suggested that the absence of competing plasmid-free cells improves host cell viability and enables increased productivity with SCS. With the process developed, 12.8 g L(-1) purified SELP was obtained, this is the highest SELP productivity reported to date and clearly demonstrates the commercial viability of these promising polymers.This work was financed by the European Commission via the 7th Framework Programme Project EcoPlast (FP7-NMP-2009-SME-3), by national funds from the FCT through EXPL/BBB-BIO/1772/2013-FCOMP-010124-FEDER-041595, the strategic programme UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) and a fellowship to SRC (SFRH/BPD/89980/2012), as well as from ERDF through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI). T.C. is supported by the FCT, the European Social Fund, the Programa Operacional Potencial Humano and the Investigador FCT Programme (IF/01635/2014). All the technical staff at the CBMA are thanked for their skilful technical assistance.info:eu-repo/semantics/publishedVersio

Nearly Complete Genome Sequences of Human Norovirus Belonging to Several Genotypes from Valencia, Spain

Human noroviruses are responsible for most nonbacterial acute gastroenteritis cases. The GII.2, GII.4, and GII.17 genotypes of human noroviruses have recently arisen as the most frequent genotypes found in humans worldwide. We report here seven nearly complete genomes of these genotypes from patients with acute gastroenteritis in Valencia, Spain

Nearly complete genome sequence of a human norovirus GII.P17-GII.17 strain isolated from Brazil in 2015

Human noroviruses are the most common cause of nonbacterial acute gastroenteritis worldwide. We report here the nearly complete genome sequence (7,551 nucleotides) of a human norovirus GII.P17-GII.17 strain detected in July 2015 in the stool sample from an adult with acute gastroenteritis in Brazil

A comprehensive assessment of the transcriptome of cork oak (Quercus suber) through EST sequencing

Background: Cork oak (Quercus suber) is one of the rare trees with the ability to produce cork, a material widely used to make wine bottle stoppers, flooring and insulation materials, among many other uses. The molecular mechanisms of cork formation are still poorly understood, in great part due to the difficulty in studying a species with a long life-cycle and for which there is scarce molecular/genomic information. Cork oak forests are of great ecological importance and represent a major economic and social resource in Southern Europe and Northern Africa. However, global warming is threatening the cork oak forests by imposing thermal, hydric and many types of novel biotic stresses. Despite the economic and social value of the Q. suber species, few genomic resources have been developed, useful for biotechnological applications and improved forest management. Results: We generated in excess of 7 million sequence reads, by pyrosequencing 21 normalized cDNA libraries derived from multiple Q. suber tissues and organs, developmental stages and physiological conditions. We deployed a stringent sequence processing and assembly pipeline that resulted in the identification of ~159,000 unigenes. These were annotated according to their similarity to known plant genes, to known Interpro domains, GO classes and E.C. numbers. The phylogenetic extent of this ESTs set was investigated, and we found that cork oak revealed a significant new gene space that is not covered by other model species or EST sequencing projects. The raw data, as well as the full annotated assembly, are now available to the community in a dedicated web portal at http://www.corkoakdb.org. Conclusions: This genomic resource represents the first trancriptome study in a cork producing species. It can be explored to develop new tools and approaches to understand stress responses and developmental processes in forest trees, as well as the molecular cascades underlying cork differentiation and disease response.Peer Reviewe

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

Isolation and characterization of bioactive compounds produced by lactic acid bacteria

Tese de Doutoramento, Ciências Agrárias, especialidade de Tecnologia Alimentar, 02 de maio de 2018, Universidade dos Açores.A caracterização de queijos tradicionais, em especial os de denominação de origem protegida, é extremamente importante, não só para a obtenção do produto final desejável, mas também de um ponto de vista económico e até ecológico. Estes queijos fabricados com leite cru são uma fonte crucial de bactérias do ácido láctico (BAL) geneticamente diversificada, que podem apresentar características promotoras de saúde e tecnológicas relevantes. Desta forma, 114 BAL isoladas de um queijo tradicional Açoriano (queijo do Pico) foram avaliadas pelo seu potencial em produzir compostos bioativos que podem ser benéficos para a saúde e para a segurança do produto final. As características tecnológicas destes isolados foram igualmente estudadas, tendo em mente o desenvolvimento de produtos funcionais com aplicações industriais. Os isolados de BAL foram primeiramente analisados pela sua capacidade de produzir substâncias antimicrobianas, bacteriocinas, contra várias bactérias patogénicas. […]. Em conclusão, o presente trabalho demonstrou o potencial de algumas estirpes de BAL isoladas do queijo do Pico, em produzir compostos bioactivos com relevância para serem utilizados no desenvolvimento de produtos alimentares funcionais.ABSTRACT: Characterization of traditional cheeses, namely those with Protected Designation of Origin (PDO) status, is of extremely importance, not only for maintaining the quality of the end product, but also for economic and even ecologic reasons. These raw milk cheeses are considered a crucial source of lactic acid bacteria (LAB), genetically diversified, that can offer particular, health promoting and technological features. So, 114 LAB isolated from a traditional Azorean cheese (Pico cheese), were studied for their potential to produce bioactive compounds that can display safety and health benefits. Technological features were also evaluated, having in mind the development of functional food products and further industrial applications. The LAB isolates were firstly screened for production of antimicrobial substances, bacteriocins, against a group of pathogenic bacteria. […]. Overall, the present work demonstrated the potential of several LAB strains isolated from Pico cheese to produce bioactive compounds with high potential to be use in the development of functional foods