Theoretical Study of the Thermolysis Reaction and Chemiexcitation of Coelenterazine Dioxetanes

Coelenterazine and other imidazopyrazinones are important bioluminescent substrates widespread in marine species and can be found in eight phyla of luminescent organisms. Light emission from these systems is caused by the formation and subsequent thermolysis of a dioxetanone intermediate, whose decomposition allows for efficient chemiexcitation to singlet excited states. Interestingly, some studies have also reported the involvement of unexpected dioxetane intermediates in the chemiand bioluminescent reactions of Coelenterazine, albeit with little information on the underlying mechanisms of these new species. Herein, we have employed a theoretical approach based on density functional theory to study for the first time the thermolysis reaction and chemiexcitation profile of two Coelenterazine dioxetanes. We have found that the thermolysis reactions of these species are feasible but with relevant energetic differences. More importantly, we found that the singlet chemiexcitation profiles of these dioxetanes are significantly less efficient than the corresponding dioxetanones. Furthermore, we identified triplet chemiexcitation pathways for the Coelenterazine dioxetanes. Given this, the chemiexcitation of these dioxetanes should lead only to minimal luminescence. Thus, our theoretical investigation of these systems indicates that the thermolysis of these dioxetanes should only provide dark pathways for the formation of nonluminescent degradation products of the chemi- and bioluminescent reactions of Coelenterazine and other imidazopyrazinones

Abordagem da nutrição em manuais escolares: um estudo longitudinal

No âmbito do Projeto Europeu “BIOHEAD-CITIZEN”, desenvolveu-se em 19 países Europeus, Africanos e do Médio Oriente uma grelha de análise para o estudo de manuais dos ensinos básico e secundário, acerca de Educação para a Saúde. Neste estudo procedeu-se à análise histórica de manuais portugueses. Verificamos que é dado progressivamente mais ênfase ao tópico nutrição nos manuais analisados, o que poderá estar relacionado com uma progressiva alteração nos hábitos alimentares dos Portugueses.undação para a Ciência e a Tecnologia (FCT) - CIEC unidade de investigação 31

Possible implications of a poultry fungal contamination

Introdução – Apesar de em Portugal se verificar o aumento da indústria da produção de aves para consumo humano, apenas alguns estudos incidem sobre a qualidade do ar interior e as implicações da sua degradação. Objectivos – Descrever a contaminação fúngica num aviário, analisar possíveis associações com a temperatura ambiente e a humidade relativa e o possível impacto na saúde dos consumidores e trabalhadores desta unidade. Métodos – Foi desenvolvido um estudo descritivo para avaliar a contaminação fúngica num aviário. Colheram‑se 5 amostras de ar de 100 litros através do método de compactação e 4 amostras de superfícies, utilizando a técnica da zaragatoa e um quadrado de 10 cm de lado de metal. Simultaneamente, os parâmetros ambientais – temperatura ambiente e humidade relativa – também foram medidos. Resultados – Foram identificadas vinte espécies de fungos no ar, sendo os seguintes os quatro géneros mais comummente isolados: Cladosporium (40,5%), Alternaria (10,8%), Chrysosporium e Aspergillus (6,8%). Nas superfícies, 21 espécies de fungos foram identificadas, sendo os 4 géneros mais identificados Penicillium (51,8%), Cladosporium (25,4%), Alternaria (6,1%) e Aspergillus (4,2%). Importa referir o facto de Aspergillus flavus, também isolado no ar, ser reconhecido como produtor de micotoxinas (aflatoxina) e Aspergillus fumigatus, uma das espécies isoladas no ar e superfícies, ser capaz de causar aspergilose grave ou fatal. Não se verificou relação significativa (p> 0,05) entre a contaminação fúngica e as variáveis ambientais. Conclusão – Caracterizou‑se a distribuição fúngica no ar e superfícies do aviário e analisou‑se a possível influência das variáveis ambientais. Foi reconhecido um potencial problema de Saúde Pública devido à contaminação fúngica e à possível produção de micotoxinas com a eventual contaminação dos produtos alimentares. A contaminação fúngica, particularmente causada pelo Aspergillus fumigatus, e a possível presença de micotoxinas no ar, devem ser encaradas também como fatores de risco neste contexto ocupacional. ABSTRACT - Background – Although there is an increasingly industry that produce whole chickens for domestic consumption in Portugal, only few investigations have reported on the indoor air of these plants and the consequences of their degradation. Objectives – Describe one poultry environmental fungal contamination analyse possible associations between temperature and relative humidity and its possible impact on the health of consumers and of the poultry workers. Methods – A descriptive study was developed to monitor one poultry fungal contamination. Five air samples of 100 litres through impaction method were collected and 4 swab samples from surfaces were also collected using a 10 cm square of metal. Simultaneously, environmental parameters – temperature and relative humidity – were also measured. Results – Twenty species of fungi in air were identified, being the 4 most commonly isolated the following genera: Cladosporium (40.5%), Alternaria (10.8%), Chrysosporium and Aspergillus (6.8%). In surfaces, 21 species of fungi were identified, being the 4 genera more identified Penicillium (51.8%), Cladosporium (25.4%), Alternaria (6.1%) and Aspergillus (4.2%). In addition, Aspergillus flavus also isolated in the poultry air is a well‑known producer of potent mycotoxins (aflatoxin), and Aspergillus fumigatus, one of the species isolated in air and surfaces, is capable of causing severe or fatal aspergillosis. There was no significant relationship (p>0,05) between fungal contamination and environmental variables. Conclusions – Was characterized fungal distribution in poultry air and surfaces and analyzed the association of environmental variables. It was recognized the Public Health problem because of fungal contamination and also due to probable mycotoxins production with the possible contamination of food products. Fungal contamination, particularly due to the presence of Aspergillus fumigatus and also the possible presence of mycotoxins in the air, should be seen as risk factor in this occupational setting

Neurospora crassa mat A-2 and mat A-3 proteins weakly interact in the yeast two-hybrid system and affect yeast growth

Mating-type genes control the entry into the sexual cycle, mating identity and sexual development in fungi. The mat A-2 and mat A-3 genes, present in the mat A idiomorph of the filamentous fungus Neurospora crassa, are required for post-fertilization functions but are not essential for mating identity. Their putative roles as transcription factors are based on the similarity of mat A-2 with the Podospora anserina SMR1 gene and an HMG motif present in the mat A-3 gene. In this work the yeast two-hybrid system was used to identify transcriptional activity and protein-protein interaction of N. crassamat A-2 and mat A-3 genes. We observed that the mat A-3 protein alone is capable of weakly activating transcription of yeast reporter genes; it also binds with low specificity to the GAL1 promoter sequence, possibly due to its HMG domain. Our results also indicate that mat A-3 is capable to form homodimers, and interact with mat A-2. Interference on yeast growth was observed on some transformants suggesting a toxic action of the mat A-2 protein. Our data on pattern of interactions of mat proteins contributes towards understanding the control of vegetative and sexual cycles in filamentous fungi

Phenolic acids and derivatives: studies on the relationship among structure, radical scavenging activity, and physicochemical parameters

The antiradical activity of caffeic acid (1), dihydrocaffeic acid (5), and their corresponding n-alkyl esters was evaluated by using the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(*)) method. Dihydrocaffeic acid (5) was the most potent compound, having an antiradical effect higher than that of (+/-)-alpha-tocopherol, whereas caffeic acid (1) was less efficient. Esterification of the carboxyl group of dihydrocaffeic acid (5) had a dramatic effect on its antiradical potency, but similar effects were not observed for caffeic acid (1) derivatives. The n-alkyl esters of both phenolic series had similar potencies, and their antiradical activities were independent of the alkyl chain length. Dose-dependent scavenger effects were found in both series. Acid-base properties of the compounds, evaluated by using potentiometry and spectrophotometry, showed that the catechol moiety had pK(a2) and pK(a3) values of 9. 24-9.02 and 11.38-10.99 in the dihydrocaffeic series and 8.48-8.24 and 11.38-11.07 in the caffeic series, respectively. Antiradical activity and pK(a) values of the compounds were not related.info:eu-repo/semantics/publishedVersio

Attitudes toward money and control strategies of financial behavior: a comparison between overindebted and non-overindebted consumers

This paper addresses whether overindebted and non-overindebted consumers differ in their attitude toward money (specifically, the degree to which consumers care about money and feel difficulties keeping track of their money) and how this attitude impacts three different financial behavior categories: record keeping (e.g., recording spending in writing), adjusting balance (e.g., trying to find ways to decrease one’s expenses to match income), and monitoring balance (e.g., monitoring one’s spending to see if it is in line with what is expected). Overindebted consumers were recruited via an NGO for consumer defense and were categorized (whenever possible) into two subgroups: consumers who became overindebted due to internal causes (e.g., bad financial management) and consumers who became overindebted due to external causes (e.g., unemployment). Non-overindebted consumers were a convenience sample. Non-overindebted consumers showed more positive attitudes toward money than both groups of overindebted consumers and overindebted due to external causes showed more positive attitudes than overindebted consumers due to internal causes. All groups share similar financial management behaviors except for monitoring balance, which was more frequent among non-overindebted consumers. Furthermore, a regression analysis indicates that money attitudes helped explain financial behavior differences between consumers above and beyond their indebtedness status. Consumers’ attitude predicted financial behaviors, even when controlling for relevant socioeconomic variables (education, income, age, and gender). Further analyses comparing money attitudes and financial behavior for the three subgroups (non-overindebted, overindebted due to internal causes, and overindebted due to external causes) showed no differences.info:eu-repo/semantics/publishedVersio

Taxas de mortalidade entre os idosos de Belo Horizonte, 1996 e 2006: uma breve análise por sexo e principais causas de morte

In Brazil and all over the world, in parallel with the demographic transition, due to advances in medicine and health care, there has been an increase in the life expectancy and longevity of the elderly. This combination of factors causes changes in the pattern of morbidity and mortality which can be assessed by simple measures of both morbidity and mortality. In this study we used indicators of mortality (General mortality rates for the elderly and rates by age groups) for the elderly popula tion 65 years and more Belo Horizonte in 1996 and 2006. The main results are that (1) there is a trend of decrease of mortality rates of the elderly among the younger men and women for the most represented causes of death, (2) most often causes of death changed during the period, (3) differences could be observed for males and for females. Finally, it is important to emphasize that it is worrysome that ill defined causes of death were among the most common causes for men and women.Brazil, mortality

Monitorização das propriedades de textura, organoléticas e microbiológicas de fiambre de perna de porco fatiado e embalado em atmosfera modificada ao longo do seu tempo de vida

O uso de atmosfera modificada (AM), como técnica de conservação na embalagem de produtos fatiados cárnicos, tem sido uma solução eficaz para assegurar a qualidade do produto e prolongar o respetivo tempo de vida útil, podendo alcançar mercados mais longínquos. Amostras de fiambre da perna extra de porco, foram embaladas com uma mistura de gás com 30% de CO2 e 70% de N2, em bandejas termoformadas de APET/EVOH/PE e seladas com filme PE/PVDC. Ao longo de 35 dias foi monitorizada a evolução da composição da mistura de gases, determinados parâmetros físico-químicos, tais como pH, teor de humidade, parâmetros de cor e textura, propriedades organoléticas e microbiológicas. O fiambre foi também avaliado sensorialmente, através de uma análise descritiva quantitativa, em relação ao brilho, cor, aroma, aparência global, flavour, textura (dureza e coesividade) e sabor a sal. Os resultados dos parâmetros físico-químicos não revelaram diferenças significativas ao longo do tempo de armazenamento , com a excepção de alterações na intensidade da cor e ligeiras alterações de textura. O painel detetou diferenças entre produtos frescos e os tempo s mais tardios de armazenamento. Não foram detetad os microrganismos patogénicos em nenhuma das amostras analisadas.Projecto n.º 38869 EXTRASLICED45, co - financiado pelo FEDER através do COMPETE - POFC, no âmbito do QREN 2007 - 201

Corncob cellulose scaffolds: A new sustainable temporary implant for cartilage replacement

Tissue engineering using scaffolds is a promising strategy to repair damaged articular cartilage, whose self-repair is inefficient. Cellulose properties have been recognized for their application in the biomedical field. The aim of this study was to fabricate and characterize novel scaffolds based on poly(E-caprolactone) (PCL) and sustainable cellulose. Thus, the performance of corncob-derived cellulose (CC) in scaffolds as an alternative to wood cellulose (WC) was also investigated to reduce the environmental footprint. Two concentrations of CC in scaffolds were tested, 1% and 2% (w/w), and commercial WC using the same concentrations, as a control. Morphologically, all the developed scaffolds presented pore sizes of ~300 m, 10 layers, a circular shape and well-dispersed cellulose. Thus, all of these characteristics and properties provide the manufactured scaffolds suitable for use in cartilage-replacement strategies. The use of 2% CC results in higher porosity (54.24%), which promotes cell infiltration/migration and nutrient exchange, and has similar mechanical properties to WC. As for the effects of enzymatic degradation of the scaffolds, no significant changes (p > 0.05) were observed in resistance over time. However, the obtained compressive modulus of the scaffold with 2% CC was similar to that of WC. Overall, our results suggest that the integration of 2% corncob cellulose in PCL scaffolds could be a novel way to replace wood-cellulose-containing scaffolds, highlighting its potential for cartilage-replacement strategies.info:eu-repo/semantics/publishedVersio