N-(5-Amino-9H-benzo[a]phenoxazin-9-ylidene)propan-1-aminium chlorides as antifungal agents and NIR fluorescence probes

The search for benzo[a]phenoxazines, Nile Blue derivatives, with high antifungal activity and cell labelling capacity based on our previously published works in this type of compounds, led us to the design of compounds with specific substituents in the polycyclic system. Thus, in the present work, four new benzo[a]phenoxazinium chlorides, possessing at the 5-position amino or (3-aminopropyl) amino groups and at the 9-position propylamino or dipropylamino groups, were synthesized. Another analogue, with (3-aminopropyl) amino group at 5-position, ethyl amino group at 9-position and a methyl group at 10-position of the polycyclic system was also synthesized for comparison in the studies performed. Fundamental photophysics (absorption and fluorescent emission) was carried out in absolute ethanol, water, and other aqueous solutions of different pH values, relevant for the potential biological applications of these compounds. The antiproliferative activity of the synthesized benzo[a]phenoxazinium chlorides was determined using Saccharomyces cerevisiae PYCC 4072 and the microdilution method described for antifungal susceptibility tests in yeast. All compounds revealed antifungal activity, being the most active the one possessing an amino group at 5-position and an aminopropyl group at 9-position. The potential as fluorescent probes were evaluated by fluorescence microscopy, using S. cerevisae as a model system of eukaryotic cells, and it was found that the benzo[a]phenoxazinium chlorides stained the cells with preferential accumulation that seems to appear at the vacuolar membrane and/or the perinuclear membrane of the endoplasmatic reticulum.Thanks are due to Fundação para a Ciência e Tecnologia (FCT) and FEDER (European Fund for Regional Development)-COMPETE-QRENEU for financial support through the research centres CQ/UM (UID/QUI/0686/2019 and UIDB/00686/2020) and CBMA (PEst-OE/BIA/UI4050/2019 and UID/BIA/04050/2020), as well as a PhD grant to J. C. F. (SFRH/BD/133207/2017). The NMR spectrometer Bruker Avance III 400 is part of the National NMR Network (PTNMR) and is partially supported by Infrastructure Project No. 022161 (co-financed by FEDER through COMPETE 2020, POCI and PORL and FCT through PIDDAC)

Factores condicionantes da dádiva benévola de sangue em estudantes universitários em Luanda

A proporção de colheitas de dadores voluntários pode ser usada como indicador não só do potencial de disponibilidade de sangue mas também da sua segurança. Em Luanda, Angola, a dádiva voluntária correspondeu a cerca de 23% das dádivas em 2004. Foi realizado um estudo observacional descritivo transversal pela aplicação de um questionário constituído por itens que captam factores que motivam ou inibem a dádiva benévola de sangue, numa amostra de estudantes universitários em Luanda. Apesar da baixa dádiva voluntária indicada pelos respondentes, verificou-se uma elevada disponibilidade para a dádiva benévola, essencial no combate ao HIV.The proportion of voluntary blood donors can be used as an indicator not only of the potential availability of blood supplies but also its safety. In Luanda, Angola, the voluntary donation was about 23% of all donations in 2004. We conducted a cross-sectional observational study through questionnaire application which captured factors that motivate or inhibit the benevolent blood donation, among a sample of university students in Luanda. Despite the low voluntary donation indicated by respondents there was a high availability for the voluntary donation, essential in fighting HIV

Self-Similarity of Friction Laws

The change of the friction law from a mesoscopic level to a macroscopic level is studied in the spring-block models introduced by Burridge-Knopoff. We find that the Coulomb law is always scale invariant. Other proposed scaling laws are only invariant under certain conditions.}Comment: Plain TEX. Figures not include

Light Intensity Activity: a possible contribution to delay frailty

Trabalho apresentado em 24th Nordic Congress of Gerontology, 2-4 maio 2018, Oslo, NoruegaN/

Exploring plant tissue culture to improve the production of phenolic compounds: a review

Plant tissue and organ culture has been extensively used from the beginning of the XX century for the study and comprehension of some primary biological mechanisms such as morphogenesis. However, with the increasing demand of the market for novel products derived from plants, in vitro culture became a reliable technique for the mass production of plant material. Moreover, the potential to use this technique for the production of some bioactive compounds, such as phenolic compounds, is immense since it allows the manipulation of the biosynthetic routes to increase the production and accumulation of specific compounds. This work intends to make a brief historical review of in vitro culture, highlighting its use for the production of bioactive compounds. Also, emphasizes the importance of phenolic compounds for the consumer as well reviews the metabolic pathways involved in its production in plant cells. Furthermore, it was carried out a comprehensive study on the work developed for the production of plant phenolic compounds in in vitro cultures, as well as on the type of elicitors used to increase of the same production; also a brief highlighting of the phenolic compounds which serve as elicitors. There are numerous reports directed to the production of phenolic extracts in in vitro plant cultures, however there is a lack in the production of individual phenolic compounds mainly due to the complexity of the biosynthetic routes and extraction procedures. Elicitation procedures are often used to increase the production of phenolics, archieving in most cases higher yields than in non-elicitated cultures. The increasing production of bioactive phenolic extracts/compounds allows for their further applicability, namely in the industry of functional foods or in pharmaceutical/medical fields.The authors are grateful to Fundação para a Ciência e a Tecnologia (FCT, Portugal) for financial support to CIMO (strategic project PEst-OE/AGR/UI0690/2014) and M.I. Dias grant (SFRH/BD/84485/2012). This work received financial support from the European Union (FEDER funds through COMPETE) and National Funds (FCT) through project UID/QUI/50006/2013, and FEDER funds under the framework of QREN through Project NORTE-07-0124-FEDER-000069

New Nile blue derivatives as NIR fluorescent probes and antifungal agents

The synthesis of four new Nile Blue derivatives with hydrogen, propyl and/or aminopropyl groups as substituents of the amines of 5- and 9-positions is described. Photophysical properties were evaluated in acidified ethanol and aqueous solution at physiological pH. Antifungal activity is also studied through the obtention of MIC values.Thanks are due to Fundação para a Ciência e Tecnologia (FCT) and FEDER (European Fund for Regional Development)-COMPETE-QRENEU for financial support through the Chemistry Research Centre of the University of Minho (Ref. UID/QUI/00686/2013 and UID/QUI/0686/2016), CBMA (PEst OE/BIA/UI4050/2014) and a PhD grant to J.C.F. (SFRH/BD/133207/2017). The NMR spectrometer Bruker Avance III 400 is part of the National NMR Network (PTNMR) and are partially supported by Infrastructure Project No 022161 (co-financed by FEDER through COMPETE 2020, POCI and PORL and FCT through PIDDAC)

Procedure validation and laboratory performance monitoring for the measurement of moisture, ash and volatile matter mass fractions in solid biofuels

Participation in interlaboratory comparisons is a requirement of the accreditation bodies for granting laboratory accreditation by EN ISO/IEC 17025:2005 as external quality control. Proficiency testing (PT) is used to demonstrate the individual performance of a laboratory for a specific test or measurement. Monitoring PT performance over time shows the continuing performance and allows the identification of potential problems related to random and systematic errors. In this study, it is shown that the procedures applied to measure mass fractions of moisture, ash and volatile matter in solid fuels fulfill the conditions stated in the European standards EN 14774-3, EN 14775 and EN 15148:2009 regarding target uncertainty, repeatability and reproducibility. Repeatability was assessed from sample duplicate analysis and combined standard uncertainty. Limits of detection and quantification were also estimated although no target values are stated. The obtained values fulfill the requirements for specifications and classes of solid biofuels. Laboratory performance over the time from 2011 to 2013 regarding such measurements was evaluated with 18 materials provided by WEPAL within the BIMEP program. Apart from monitoring the individual z-scores, their sequence was checked with summarizing parameters including the ‘rescaled sum z-scores’, RSZ, the ‘sum squared z-scores’, SSZ, and J-scores. For none of the analytes, the parameters indicated a trend over time and therefore it was not necessary to trigger any investigation or correcting procedure.

Statistical Analysis of the Leadership Perceptions in a Public Administration Office

This Journal is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.The main purpose of this paper is to identify and characterize the leadership features in a public administration office of the Azores (Autonomous Region of the Azores), in orders to verify the existence or not of a positive leadership based on the employees’ perceptions. The main conclusions are attained using data gathered via a previously tested and validated questionnaire. Overall, we conclude that subordinates don’t consider that their leaders show behaviors that they can associate with a totally positive and effective leadership although they are pleased with the fact that they are not extremely controllers and that they seek to do what the majority of the subordinates wants.info:eu-repo/semantics/publishedVersio

Novel benzo[α]phenoxazinium chlorides functionalized with sulfonamide groups as NIR fluorescent probes for vacuole, endoplasmic reticulum, and plasma membrane staining

The demand for new fluorophores for different biological target imaging is increasing. Benzo[a]phenoxazine derivatives are fluorochromophores that show promising optical properties for bioimaging, namely fluorescent emission at the NIR of the visible region, where biological samples have minimal fluorescence emission. In this study, six new benzo[a]phenoxazinium chlorides possessing sulfonamide groups at 5-amino-positions were synthesized and their optical and biological properties were tested. Compared with previous probes evaluated using fluorescence microscopy, using different S. cerevisiae strains, these probes, with sulfonamide groups, stained the vacuole membrane and/or the perinuclear membrane of the endoplasmic reticulum with great specificity, with some fluorochromophores capable of even staining the plasma membrane. Thus, the addition of a sulfonamide group to the benzo[a]phenoxazinium core increases their specificity and attributes for the fluorescent labeling of cell applications and fractions, highlighting them as quite valid alternatives to commercially available dyes.FCT (Fundação para a Ciência e Tecnologia, Portugal) and FEDER (European Fund for Regional Development)-COMPETEQREN-EU for financial support to the research centers CQ/UM (UID/QUI/00686/2021), and CBMA (Ref. UIDB/04050/2020), as well as a PhD grant to J. C. Ferreira (SFRH/BD/133207/2017 and COVID/BD/151978/2021). The NMR spectrometer Bruker Avance III 400 (part of the National NMR Network) was financed by FCT and FEDER

The venom of South American rattlesnakes inhibits macrophage functions and is endowed with anti-inflammatory properties

The injection of Crotalus durissus terrificus venom into the foot pad of mice did not induce a significant inflammatory response as evaluated by oedema formation, increased vascular permeability and cell migration. The subcutaneous injection of the venom, or its addition to cell cultures, had an inhibitory effect on the spreading and phagocytosis of resident macrophages, without affecting the viability of the cells. This effect was not observed when the venom was added to cultures of thioglycollate elicited macrophages, but it was able to inhibit these macrophage functions when the cells were obtained from animals injected simultaneously with the venom and thioglycollate. These observations suggest that the venom interferes with the mechanisms of macrophage activation. Leukocyte migration induced by intraperitoneal injection of thioglycollate was also inhibited by previous venom injection. This down-regulatory activity of the venom on macrophage functions could account for the mild inflammatory response observed in the site of the snake bite in Crotalus durissus terrificus envenomation in man