Potencial da espectroscopia de fluorescência induzida por laser para separar variedades de laranja geneticamente parecidas.

Entrada padronizada: VILLAS-BOAS, P. R

MEASURING THE WAVE DISSIPATION PRODUCED BY A SWIMMING-LINE SEPARATION ROPE

Hydrodynamic drag (D) seems to be one of the major determinants of swimming performance. D is usually divided into pressure, friction and wave drag (Dw). Meanwhile, Dw can be due to two distinct phenomena: (i) wave production (Dwwp) and (ii) transfer of negative wave momentum (Dwtm). Dwwp refers to the energy dissipated from the kinetic energy of the swimmer and used to generate waves, and Dwtm refers to the drag effect (reduction of forward kinetic energy of the swimmer) attributed to the impact of waves produced by others, or produced by the swimmer itself and rebounded at a swimming pool wall. In order to define the competition lane of each swimmer, the competition swimming pools dispose of swimming-line separation ropes (S-LSR). In the meantime, the manufacturers of this S-LSR claim that they have the ability to absorb waving energy, and thus to dissipate waves avoiding Dw tm, and other perturbing wave effects. The purpose of this research was to characterize the swimmer’s wave production, and to measure the effect upon the wave energy dissipation of a common S-LSR (Fig.1)

Phage therapy as an alternative or complementary strategy to prevent and control biofilm-related infections

The complex heterogeneous structure of biofilms confers to bacteria an important survival strategy. Biofilms are frequently involved in many chronic infections in consequence of their low susceptibility to antibiotics as well as resistance to host defences. The increasing need of novel and effective treatments to target these complex structures has led to a growing interest on bacteriophages (phages) as a strategy for biofilm control and prevention. Phages can be used alone, as a cocktail to broaden the spectra of activity, or in combination with other antimicrobials to improve their efficacy. Here, we summarize the studies involving the use of phages for the treatment or prevention of bacterial biofilms, highlighting the biofilm features that can be tackled with phages or combined therapy approaches.This work was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the project PTDC/BBB-BSS/6471/2014, the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684). This work was also supported by BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 – Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

Cytotoxicity of Portuguese propolis: the proximity of the in vitro doses for tumor and normal cell lines

With a complex chemical composition rich in phenolic compounds, propolis (resinous substance collected by Apis mellifera from various tree buds) exhibits a broad spectrum of biological activities. Recently, in vitro and in vivo data suggest that propolis has anticancer properties, but is the cytoxicity of propolis specific for tumor cells? To answer this question, the cytotoxicity of phenolic extracts from Portuguese propolis of different origins was evaluated using human tumor cell lines (MCF7-breast adenocarcinoma, NCI-H460-non-small cell lung carcinoma, HCT15-colon carcinoma, HeLa-cervical carcinoma, and HepG2-hepatocellular carcinoma), and non-tumor primary cells (PLP2). The studied propolis presented high cytotoxic potential for human tumor cell lines, mostly for HCT15. Nevertheless, excluding HCT15 cell line, the extracts at the GI50 obtained for tumor cell lines showed, in general, cytotoxicity for normal cells (PLP2). Propolis phenolic extracts comprise phytochemicals that should be further studied for their bioactive properties against human colon carcinoma. In the other cases, the proximity of the in vitro cytotoxic doses for tumor and normal cell lines should be confirmed by in vivo tests and may highlight the need for selection of specific compounds within the propolis extract.The authors are grateful to Foundation for Science and Technology (FCT), Portugal, for providing the financial support to the research centers CIMO (PEst-OE/AGR/UI0690/2011) and CQ-UM (PEst-C/QUI/UI0686/2011). Ricardo C. Calhelha thanks FCT, POPH-QREN, and FSE for his Grant (SFRH/BPD/68344/2010). Thanks are also due to the National Federation of Portuguese Beekeepers for supplying propolis samples

HOW TO START IN BACKSTROKE CONSIDERING THE NEW RULES?

FINA recently changed the rule that governs the starting position for the backstroke starting technique. With this change, swimmers may now decide to start with the feet emerged, which was previously strictly forbidden. This new liberalization naturally determines the rise of a new technical question for swimmers and coaches: do a starting position with the feet emerged allow a better performance, or better performance conditions for the following actions? To our knowledge no previous scientific results are available concerning this question, allowing to support any technical decision. During this presentation we will try to deliver arguments to support a technical option in this particular topic, based on the research developed by our group, comparing the traditional starting technique with the feet immerged (BSFI), with the one allowed nowadays, with both feet totally, or partially, emerged (BSFE). To fulfil this purpose, we studied six experienced male swimmers that maximally performed 4 repetitions of each technique over a distance of 15 meters. All performances were dual-media videotaped (50 Hz) in the sagittal plane, synchronized with kinetic and EMG data simultaneously registered. Kinetic data were assessed using an underwater force plate mounted on a special support on the wall of the pool, allowing the registration of the horizontal component of the forces exerted by the swimmers’ feet. The handgrip system was adapted to reproduce its legal position and configuration, but instrumented with a load cell (Globus, Italy) to allow the assessment of the horizontal component of the forces exerted by swimmers’ upper limbs. Findings pointed out that BSFI was significantly faster till the 5m reference, with less muscular activity, and with a tendency to produce higher forces against the starting wall. No argument was obtained to support the use of the BSFE in swimming competitions

The Stellar Content of Obscured Galactic Giant HII Regions V: G333.1--0.4

We present high angular resolution near--infrared images of the obscured Galactic Giant HII (GHII) region G333.1--0.4 in which we detect an OB star cluster. For G333.1--0.4, we find OB stars and other massive objects in very early evolutionary stages, possibly still accreting. We obtained $K$--band spectra of three stars; two show O type photospheric features, while the third has no photospheric features but does show CO 2.3 $\mu$m band--head emission. This object is at least as hot as an early B type star based on its intrinsic luminosity and is surrounded by a circumstellar disc/envelope which produces near infrared excess emission. A number of other relatively bright cluster members also display excess emission in the $K$--band, indicative of disks/envelopes around young massive stars. Based upon the O star photometry and spectroscopy, the distance to the cluster is 2.6 $\pm$ 0.4 kpc, similar to a recently derived kinematic (near side) value. The slope of the $K$--band luminosity function is similar to those found in other young clusters. The mass function slope is more uncertain, and we find $-1.3 \pm 0.2 < \Gamma < -1.1 \pm 0.2$- for stars with M $> 5$ M$_\odot$ where the upper an lower limits are calculated independently for different assumptions regarding the excess emission of the individual massive stars. The number of Lyman continuum photons derived from the contribution of all massive stars in the cluster is 0.2 $\times$ $10^{50}$ $s^{-1}$ $< NLyc < 1.9$ $\times$ $10^{50}$ $s^{-1}$. The integrated cluster mass is 1.0 $\times$ $10^{3}$ $M_\odot < M_{cluster} < 1.3$ $\times$ $10^{3}$ $M_\odot$.Comment: 31 pages, including 12 figures and 3 tables. Accepted for publication in the A

Bioactive compounds in wines produced in a new area for vitiviniculture in Brazil.

Wines are known for its high content of bioactive compounds that can be influenced by the region and climate where the grapes are produced. New regions of production are normally developed using techniques and standards for other traditional regions, but is important to characterize the wine profile, which is different according to the terroir, and can be important for future geographic indications. The aim of this study was to evaluate color, antioxidant activity, anthocyanin content and phenolic compounds profile in wines produced in Minas Gerais State, Brazil. Wines were produced in different wineries of the same region using the varieties Syrah, Merlot, Cabernet Sauvignon, Cabernet Franc (red), Chardonnay and Sauvignon Blanc (white) and Syrah (rose), from municipalities of Cordislândia, Boa Esperança and Três Corações, located in the south of Minas Gerais State, Brazil. Wines produced in Minas Gerais State presented contents of t-resveratrol, total phenolics, anthocyanins, flavonols, flavanols and phenolic acids consistent to the contents observed in wines from traditional regions of production. However, the terroir and the grape variety can result in a differentiation of compounds observed in wines. Syrah red wines produced in Boa Esperança stood out with higher amounts of anthocyanins (24.29 mg L-1), phenolic acids (123,19 mg L-1 ) and flavonols (35.55 mg L-1), when compared to wines from the same variety from other municipalities and other evaluated red wines. Sauvignon Blanc wines from Boa Esperança presented higher contents of phenolic acids and total flavonols, when compared to wines of the same variety produced in Cordislândia. Chardonay wines presented higher total phenolics content, when compared to ohther evaluated white wines. Rose wine produced in the South of Minas Gerais presented the phenolic acids content of 36,33 mg L-1 and total flavonols content of 29,7 mg L-1. The highest antioxidant activity using the DPPH method, (% of free radicals scavenging - FRS) was observed for Syrah wines from Três Corações, (75.37%), but not different from Cabernet Sauvignon wines from Cordislândia (72.50%), values that can be correlated with the largest content of phenolics observed in wines as phenolic compounds (3009 mg L-1). No differences were observed in the contents of the antioxidant activity of white wines. This results indicate that the studied wines present the necessary nutritional and beneficial characteristics to compete in the supply of bioactive compounds during consumption, when compared to wines produced in traditional and different regions in Brazil and other countries

Early Cytokine-Induced Transient NOX2 Activity Is ER Stress-Dependent and Impacts β-Cell Function and Survival

In type 1 diabetes (T1D) development, proinflammatory cytokines (PIC) released by immune cells lead to increased reactive oxygen species (ROS) production in β-cells. Nonetheless, the temporality of the events triggered and the role of different ROS sources remain unclear. Isolated islets from C57BL/6J wild-type (WT), NOX1 KO and NOX2 KO mice were exposed to a PIC combination. We show that cytokines increase O2 •− production after 2 h in WT and NOX1 KO but not in NOX2 KO islets. Using transgenic mice constitutively expressing a genetically encoded compartment specific H2O2 sensor, we show, for the first time, a transient increase of cytosolic/nuclear H2O2 in islet cells between 4 and 5 h during cytokine exposure. The H2O2 increase coincides with the intracellular NAD(P)H decrease and is absent in NOX2 KO islets. NOX2 KO confers better glucose tolerance and protects against cytokine-induced islet secretory dysfunction and death. However, NOX2 absence does not counteract the cytokine effects in ER Ca2+ depletion, Store-Operated Calcium Entry (SOCE) increase and ER stress. Instead, the activation of ER stress precedes H2O2 production. As early NOX2-driven ROS production impacts β-cells’ function and survival during insulitis, NOX2 might be a potential target for designing therapies against early β-cell dysfunction in the context of T1D onset