2,449 research outputs found
Acute toxicity of plant extracts towards Daphnia magna
The demand for natural based products for the cosmetics industry is increasing sharply and therefore
the search for new alternatives to the traditionally used plants is growing. These alternative plants
can be an important source of bioactive compounds under a circular economy approach. Within the
framework of Inovep project, several plant species, some of which autochthonous from Portugal,
were identified as potential sources of bioactive compounds, namely: gum rockrose (Cistus
ladanifer), curry plant (Helichrysum italicum), hop (Humulus lupulus), Mediterranean thyme
(Thymbra capitata) and basil (Ocimum basilicum). Considering the potential future use of these plant
extracts by the industry, it is necessary to assess the risk associated with their introduction into the
ecosystem. This work aims to evaluate the toxic effects of different extracts of these five species.
Acute toxicity tests using the model organism Daphnia magna were performed and the
immobilization after 24 and 48 hours of exposure was evaluated. The EC50 (the concentration
estimated to immobilize 50 per cent of the Daphnia) varied from 201.8±3.28 x10-5 mg.L-1 at 24
hours and 199.5±5.9410x10-5 mg.L-1 at 48 hours for Cistus ladanifer extract and 11.2±0.2403 mg.L-
1 at 24 hours and 11.2±0.4095 mg.L-1 at 48 hours for Thymbra capitata essential oil. For Humulus
lupulus, Helichrysum italicum, Thymbra capitata in the form of hidrolate, and Ocimum basilicum no
immobilization was observed until the highest concentrations tested for various types of extracts,
suggesting these extracts present low to no risk towards D. magna
Processing zucchini (Cucurbita pepo L.) with low UV-C radiation
Recent developments regarding the antimicrobial properties of certain types of light sources have promoted a growing interest in these applications, especially with concern to their potentialities for food processing. Ultraviolet radiation in the range of 200-280 nm is lethal to most microorganisms, including bacteria, viruses, fungi and yeasts. Fresh and artificially contaminated zucchini (Cucurbita pepo L.), whole and cut into triangular prisms,
was exposed to UV-C lamps (Philips TUV-TL mini 8W) for different periods of time with the objective of quantifying the germicidal effect of this treatment. Triangular prism cut samples of zucchini were processed for 5, 7.5, 10, 12.5 and 15 min with different energy discharges of UV-C radiation, respectively 2.1 and 8.4 watts, whereas whole zucchini were strategically exposed for maximum time/radiation conditions (15 min - 8.4W) due to larger surface area treatments. In freshly cut samples, total counts of mesophilic bacteria were assayed, although in the case of whole vegetables, these were initially inoculated with commercial strains of Enterococcus faecalis ATCC 29212, and consequently assayed for presence of this specific microorganism.
In both cases, UV-C exposure significantly reduced microbial activity, however, in relation to the freshly cut samples, after initial reduction of mesophilic bacteria, observations of photoreactivation between 7.5 and 12.5 min were registered, with significant counts at 10 min. Decrease in bacterial growth was once again evidenced between 10 and 12.5 min but not confirmed at 15 min of exposure. As for whole contaminated vegetables, approximately 2 logarithmic reductions of the target microorganism (Enterococcus faecalis
ATCC 29212) were achieved
Estudo da Variação Intradiária das Concentrações de Pólen de Gramíneas na Atmosfera de Portugal Continental
Introdução: O pólen da família das Poaceae (gramíneas) é uma das principais fontes de aeroalergénios no mundo,
particularmente na Europa Mediterrânica. Representa, por isso, um importante factor de risco de asma, rinite e/ou conjuntivite
alérgica e constitui a principal causa de polinose em Portugal. Objectivo: Analisar a variação intradiária das
concentrações de pólen de gramíneas na atmosfera das 5 estações de monitorização continentais da Rede Portuguesa
de Aerobiologia (RPA): Porto, Coimbra, Lisboa, Évora e Portimão. Métodos: Neste estudo utilizaram -se os dados diários
e horários das monitorizações de pólen de gramíneas das cinco estações de monitorização continentais da RPA, ao
longo de 7 anos (2002 -2008). Resultados: Entre as localidades encontraram -se diferenças significativas, em termos de
Estudo da variação intradiária das
concentrações de pólen de gramíneas
na atmosfera de Portugal Continental
O pólen atmosférico de gramíneas constitui a
principal causa de rinite, asma, conjuntivite e
eczema nos indivíduos alérgicos ao pólen na
área Mediterrânica1,2, nomeadamente em Portugal3,4.
Dado que o pólen, particularmente o pólen de gramíneas,
é um factor de risco para as doenças alérgicas
respiratórias exercendo um impacto negativo sobre a
qualidade de vida dos indivíduos sensibilizados, é de
particular interesse, quer dos profissionais de saúde,
quer do doente conhecer a sua distribuição intradiária,
ou seja a variação horária das concentrações de pólen
de gramíneas ao longo do dia, de modo a adequar de
forma mais eficaz medidas de evicção e de intervenção
terapêutica.
curvas horárias. O pólen encontrou -se presente na atmosfera durante 24 horas em todas as localidades, e os valores
das concentrações horárias variaram ao longo do dia e de ano para ano. As concentrações mais baixas registaram -se
entre as 22 e as 6 horas e as mais elevadas, entre as 7 e as 21 horas, as quais em Évora ultrapassaram os 30 grãos de
pólen/m3/hora. Em geral, registaram -se 2 picos de concentrações máximas, um de manhã (9 -10 horas) ou à tarde (12 -13
horas) e outro no final da tarde / início da noite (19 -20 horas). Conclusões: O ritmo diurno difere muito de local para
local. Cada localidade tem o seu próprio padrão de variação das concentrações horárias do pólen atmosférico de gramíneas
que se pode dever, quer às diferentes espécies presentes, quer às diferentes condições ambientais. O risco de
exposição variou de localidade para localidade e ao longo do dia, sendo o Porto a localidade onde este é menor, enquanto
Évora apresenta o maior risco
Type 1 Tyrosinaemia: Past and Present in a Metabolic Disease Unit
Introdução: A ti rosinemia ti po I é uma doença hereditária do metabolismo por défi ce de fumarilacetoacetase, com uma pre-
valência ao nascimento de 1:100000 e potencialmente fatal. O plano alimentar individualizado, o transplante hepato-renal e a
niti sinona são algumas das estratégias terapêuti cas.
Métodos: Estudo retrospeti vo, observacional e descriti vo de oito doentes acompanhados numa unidade de doenças meta-
bólicas, entre janeiro de 1981 e dezembro de 2012. Analisaram-se dados demográfi cos, manifestações clínicas, terapêuti ca,
evolução clínica e laboratorial.
Resultados: Na década de 80 do século passado foram diagnosti cados quatro doentes, dos quais dois faleceram em contexto
de insufi ciência hepáti ca e carcinoma hepatocelular, uma doente foi submeti da a transplante hepáti co e outra a transplante
hepato-renal. Ambas estão clinicamente bem, mantendo terapêuti ca imunossupressora. Na década seguinte foram diagnos-
ti cados dois doentes, dos quais um faleceu aos 3 meses por insufi ciência hepáti ca aguda e carcinoma hepatocelular. A outra
doente iniciou terapêuti ca com niti sinona e plano alimentar personalizado, com boa evolução clínica e laboratorial até à ado-
lescência, altura em que surgiram difi culdades escolares e de controlo metabólico, possivelmente relacionadas com períodos
de incumprimento dietéti co. O rastreio metabólico neonatal alargado permiti u diagnosti car dois doentes às 3 semanas de vida
em fase pré-sintomáti ca. Estes iniciaram plano alimentar personalizado e niti sinona e mantêm bom controlo metabólico e
desenvolvimento psicomotor adequado.
Discussão: A possibilidade de diagnósti co precoce e uti lização da niti sinona revolucionaram o prognósti co dos doentes com
ti rosinemia ti po 1. O risco de carcinoma hepatocelular e outras complicações implicam vigilância clínica, laboratorial e imagio-
lógica regular.info:eu-repo/semantics/publishedVersio
A versatile nanocarrierCubosomes, characterization, and applications
The impact of nanotechnology on the exponential growth of several research areas, particularly nanomedicine, is undeniable. The ability to deliver active molecules to the desired site could significantly improve the efficiency of medical treatments. One of the nanocarriers developed which has drawn researchers’ attention are cubosomes, which are nanosized dispersions of lipid bicontinuous cubic phases in water, consisting of a lipidic interior and aqueous domains folded in a cubic lattice. They stand out due to their ability to incorporate hydrophobic, hydrophilic, and amphiphilic compounds, their tortuous internal configuration that provides a sustained release, and the capacity to protect and safely deliver molecules. Several approaches can be taken to prepare this structure, as well as different lipids like monoolein or phytantriol. This review paper describes the different methods to prepare nanocarriers. As it is known, the physicochemical properties of nanocarriers are very important, as they influence their pharmacokinetics and their ability to incorporate and deliver active molecules. Therefore, an extensive characterization is essential to obtain the desired effect. As a result, we have extensively described the most common techniques to characterize cubosomes, particularly nanocarriers. The exceptional properties of the cubosomes make them suitable to be used in several applications in the biomedical field, from cancer therapeutics to imaging, which will be described. Taking in consideration the outstanding properties of cubosomes, their application in several research fields is envisaged.This study was supported by the Portuguese Foundation for Science and Technology
(FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, by Marie Skłodowska Curie grant (MSCA-RISE; FODIAC; 778388) and by European Regional Development Fund (ERDF)
through the Competitiveness factors Operational program—Norte 2020, COMPETE and National Funds through the FCT—under the project AgriFood XXI (NORTE- 01-0145-FEDER-000041). J.L.P.
acknowledge the Instituto de Salud Carlos III for a “Sara Borrell” grant (CD19/00250), cofounded
by European Social Fund (“El FSE invierte en futuro”). C.J.O.F. acknowledge the FCT for the grant
SFRH/149/BD/14199/2019.info:eu-repo/semantics/publishedVersio
Prospecting for bioactive molecules and biological indicator of host resistance control cattle tick, Rhipicephalus (Boophilus) microplus.
Cattle tick, Rhipicephalus (Boophilus) microplus, and tick borne diseases are a major limitation on European breeds production in subtropical regions
Can health care providers recognise a fibromyalgia personality?
OBJECTIVES: To determine if experienced health care providers (HCPs) can recognise patients with fibromyalgia (FM) based on a limited set of personality items, exploring the existence of a FM personality. METHODS: From the 240-item NEO-PI-R personality questionnaire, 8 HCPs from two different countries each selected 20 items they considered most discriminative of FM personality. Then, evaluating the scores on these items of 129 female patients with FM and 127 female controls, each HCP rated the probability of FM for each individual on a 0-10 scale. Personality characteristics (domains and facets) of selected items were determined. Scores of patients with FM and controls on the eight 20-item sets, and HCPs’ estimates of each individual’s probability of FM were analysed for their discriminative value. RESULTS: The eight 20-item sets discriminated for FM, with areas under the receiver operating characteristic curve ranging from 0.71-0.81. The estimated probabilities for FM showed, in general, percentages of correct classifications above 50%, with rising correct percentages for higher estimated probabilities. The most often chosen and discriminatory items were predominantly of the domain neuroticism (all with higher scores in FM), followed by some items of the facet trust (lower scores in FM). CONCLUSIONS: HCPs can, based on a limited set of items from a personality questionnaire, distinguish patients with FM from controls with a statistically significant probability. The HCPs’ expectation that personality in FM patients is associated with higher levels for aspects of neuroticism (proneness to psychological distress) and lower scores for aspects of trust, proved to be correct.info:eu-repo/semantics/publishedVersio
Role of alpha-1 antitrypsin genotypes in the progression of adult liver disease
info:eu-repo/semantics/publishedVersio
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