979 resultados para Rosmarinus officinalis extract


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Marine reserves have been widely implemented as tools for biodiversity conservation and fisheries management, amongst other goals. A large number of empirical studies have focused on their effects on reef fish populations. Yet, few studies have looked at their effectiveness on semelparous species such as cephalopods, in spite of their commercial importance in many coastal regions across the globe. In this study we combine behavioural (biotelemetry) and demographic (experimental fishing) data to understand the effects of the Luiz Saldanha Marine Park (LSMP) on local populations of cuttlefish, Sepia officinalis. We used a beyond-BACI design to analyze the possible effect of the implementation of a no-take area on the abundance and biomass of this species and acoustic telemetry data to assess its site fidelity and movements within the study area. Results indicate that there was no detectable effect of the implementation of the no-take area on the abundance or biomass of cuttlefish. We found evidence that acoustically tagged adult cuttlefish leave the reserve a few days or weeks after tagging. The fact that cuttlefish have low site fidelity inside the reserve and large movements across and beyond the study area explains why there is no increase in the population inside the MPA. These results suggest that small coastal marine reserves such as the LSMP are not effective in providing long term protection to cuttlefish populations and, probably, those of other short-lived, highly mobile cephalopods. (C) 2013 Elsevier B.V. All rights reserved.

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This Thesis is composed of a collection of works written in the period 2019-2022, whose aim is to find methodologies of Artificial Intelligence (AI) and Machine Learning to detect and classify patterns and rules in argumentative and legal texts. We define our approach “hybrid”, since we aimed at designing hybrid combinations of symbolic and sub-symbolic AI, involving both “top-down” structured knowledge and “bottom-up” data-driven knowledge. A first group of works is dedicated to the classification of argumentative patterns. Following the Waltonian model of argument and the related theory of Argumentation Schemes, these works focused on the detection of argumentative support and opposition, showing that argumentative evidences can be classified at fine-grained levels without resorting to highly engineered features. To show this, our methods involved not only traditional approaches such as TFIDF, but also some novel methods based on Tree Kernel algorithms. After the encouraging results of this first phase, we explored the use of a some emerging methodologies promoted by actors like Google, which have deeply changed NLP since 2018-19 — i.e., Transfer Learning and language models. These new methodologies markedly improved our previous results, providing us with best-performing NLP tools. Using Transfer Learning, we also performed a Sequence Labelling task to recognize the exact span of argumentative components (i.e., claims and premises), thus connecting portions of natural language to portions of arguments (i.e., to the logical-inferential dimension). The last part of our work was finally dedicated to the employment of Transfer Learning methods for the detection of rules and deontic modalities. In this case, we explored a hybrid approach which combines structured knowledge coming from two LegalXML formats (i.e., Akoma Ntoso and LegalRuleML) with sub-symbolic knowledge coming from pre-trained (and then fine-tuned) neural architectures.

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Extra cellular vesicles are membrane bound and lipid based nano particles having the size range of 30 to 1000 nm released by a plethora of cells. Their prime function is cellular communication but in the recent studies, the potential of these vesicles to maintain physiological and pathological processes as well as their nano-sized constituents opened doors to its applications in therapeutics, and diagnostics of variety of diseases such as cancer. Their main constituents include lipids, proteins, and RNAs. They are categorized into subtypes such as exosomes, micro-vesicles and apoptotic bodies In recent studies, extracellular vesicles that are derived from plants are gaining high regard due to their variety of advantages such as safety, non-toxicity, and high availability which promotes large scale production. EVs are isolated from mammalian and plant cells using multitude of techniques such as Ultracentrifugation, SEC, Precipitation and so on. Due to the variety in the sources as well as shortcomings arising from the isolation method, a scalable and inexpensive EV isolation method is yet to be designed. This study focusses on isolation of EVs from citrus lemon juice through diafiltration. Lemon is a promising source due to its biological properties to act as antioxidant, anticancer, and anti-inflammatory agents. Lemon derived vesicles was proven to have several proteins analogous to mammalian vesicles. A diafiltration could be carried out for successful removal of impurities and it is a scalable, continuous technique with potentially lower process times. The concentration of purified product and impurities are analysed using Size Exclusion Chromatography in analytical mode. It is also considered imperative to compare the results from diafiltration with gold standard UC. BCA is proposed to evaluate total protein content and DLS for size measurements. Finally, the ideal mode of storage of EVs to protect its internals and its structure is analysed with storage tests.

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Polycyclic aromatic hydrocarbons (PAHs) are common environmental pollutants that occur naturally in complex mixtures. Many of the adverse health effects of PAHs including cancer are linked to the activation of intracellular stress response signaling. This study has investigated intracellular MAPK signaling in response to PAHs in extracts from urban air collected in Stockholm, Sweden and Limeira, Brazil, in comparison to BP in HepG2 cells. Nanomolar concentrations of PAHs in the extracts induced activation of MEK4 signaling with down-stream increased gene expression of several important stress response mediators. Involvement of the MEK4/JNK pathway was confirmed using siRNA and an inhibitor of JNK signaling resulting in significantly reduced MAPK signaling transactivated by the AP-1 transcription factors ATF2 and c-Jun. ATF2 was also identified as a sensitive stress responsive protein with activation observed at extract concentrations equivalent to 0.1 nM BP. We show that exposure to low levels of environmental PAH mixtures more strongly activates these signaling pathways compared to BP alone suggesting effects due to interactions. Taken together, this is the first study showing the involvement of MEK4/JNK/AP-1 pathway in regulating the intracellular stress response after exposure to nanomolar levels of PAHs in environmental mixtures.

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The aim of this study was to evaluate the mutagenicity (clastogenicity/aneugenicity) of a glycolic extract of Ziziphus joazeiro bark (GEZJ) by the micronucleus assay in mice bone marrow. Antimutagenic activity was also assessed using treatments associated with GEZJ and doxorubicin (DXR). Mice were evaluated 24-48 h after exposure to positive (N-nitroso-N-ethylurea, NEU - 50 mg.kg(-1) and DXR - 5 mg.kg(-1)) and negative (150 mM NaCl) controls, as well as treatment with GEZJ (0.5-2 g.kg(-1)), GEZJ (2 g.kg(-1)) + NEU and GEZJ (2 g.kg(-1)) + DXR. There were no significant differences in the frequencies of micronucleated polychromatic erythrocytes in mice treated with GEJZ and GEJZ + DXR compared to the negative controls, indicating that GEZJ was not mutagenic. Analysis of the polychromatic:normochromatic erythrocyte ratio revealed significant differences in the responses to doses of 0.5 g.kg(-1) and 1-2 g.kg(-1) and the positive control (NEU). These results indicated no systemic toxicity and moderate toxicity at lower and higher doses of GEZJ. The lack of mutagenicity and systemic toxicity in the antimutagenic assays, especially for treatment with GEZJ + DXR, suggested that phytochemical compounds in Z. joazeiro bark attenuated DXR-induced mutagenicity and the moderate systemic toxicity of a high dose of Z. joazeiro bark (2 g.kg(-1)). Further studies on the genotoxicity of Z. joazeiro extracts are necessary to establish the possible health risk in humans and to determine the potential as a chemopreventive agent for therapeutic use.

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Lawsonia inermis mediated synthesis of silver nanoparticles (Ag-NPs) and its efficacy against Candida albicans, Microsporum canis, Propioniabacterium acne and Trichophyton mentagrophytes is reported. A two-step mechanism has been proposed for bioreduction and formation of an intermediate complex leading to the synthesis of capped nanoparticles was developed. In addition, antimicrobial gel for M. canis and T. mentagrophytes was also formulated. Ag-NPs were synthesized by challenging the leaft extract of L. inermis with 1 mM AgNO₃. The Ag-NPs were characterized by Ultraviolet-Visible (UV-Vis) spectrophotometer and Fourier transform infrared spectroscopy (FTIR). Transmission electron microscopy (TEM), nanoparticle tracking and analysis sytem (NTA) and zeta potential was measured to detect the size of Ag-NPs. The antimicrobial activity of Ag-NPs was evaluated by disc diffusion method against the test organisms. Thus these Ag-NPs may prove as a better candidate drug due to their biogenic nature. Moreover, Ag-NPs may be an answer to the drug-resistant microorganisms.

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The aim of the present study was to perform an in vitro analysis of the antimicrobial and antiproliferative potential of an extract from Anadenanthera colubrina (Vell.) Brenan (angico) and chemically characterize the crude extract. Antimicrobial action was evaluated based on the minimum inhibitory concentration (MIC), minimum bactericidal/fungicidal concentration, and the inhibition of formation to oral biofilm. Cell morphology was determined through scanning electron microscopy (SEM). Six strains of tumor cells were used for the determination of antiproliferative potential. The extract demonstrated strong antifungal activity against Candida albicans ATCC 18804 (MIC = 0.031 mg/mL), with similar activity found regarding the ethyl acetate fraction. The extract and active fraction also demonstrated the capacity to inhibit the formation of Candida albicans to oral biofilm after 48 hours, with median values equal to or greater than the control group, but the difference did not achieve statistical significance (P > 0.05). SEM revealed alterations in the cell morphology of the yeast. Regarding antiproliferative activity, the extract demonstrated cytostatic potential in all strains tested. The present findings suggest strong antifungal potential for Anadenanthera colubrina (Vell.) Brenan as well as a tendency toward diminishing the growth of human tumor cells.

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We report the first measurements of the moments--mean (M), variance (σ(2)), skewness (S), and kurtosis (κ)--of the net-charge multiplicity distributions at midrapidity in Au+Au collisions at seven energies, ranging from sqrt[sNN]=7.7 to 200 GeV, as a part of the Beam Energy Scan program at RHIC. The moments are related to the thermodynamic susceptibilities of net charge, and are sensitive to the location of the QCD critical point. We compare the products of the moments, σ(2)/M, Sσ, and κσ(2), with the expectations from Poisson and negative binomial distributions (NBDs). The Sσ values deviate from the Poisson baseline and are close to the NBD baseline, while the κσ(2) values tend to lie between the two. Within the present uncertainties, our data do not show nonmonotonic behavior as a function of collision energy. These measurements provide a valuable tool to extract the freeze-out parameters in heavy-ion collisions by comparing with theoretical models.

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Preparation of protective coating possessing antimicrobial properties is present day need as they increase the shelf life of fruits and vegetables. In the present study, preparation of agar-silver nanoparticle film for increasing the shelf life of fruits is reported. Silver nanoparticles (Ag-NPs) biosynthesised using an extract of Ocimum sanctum leaves, were mixed with agar-agar to prepare an agar-silver nanoparticles (A-AgNp) film. This film was surface-coated over the fruits, Citrus aurantifolium (Thornless lime) and Pyrus malus (Apple), and evaluated for the determination of antimicrobial activity of A-AgNp films using disc diffusion method, weight loss and shelf life of fruits. This study demonstrates that these A-AgNp films possess antimicrobial activity and also increase the shelf life of fruits.

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This work encompasses a direct and coherent strategy to synthesise a molecularly imprinted polymer (MIP) capable of extracting fluconazole from its sample. The MIP was successfully prepared from methacrylic acid (functional monomer), ethyleneglycoldimethacrylate (crosslinker) and acetonitrile (porogenic solvent) in the presence of fluconazole as the template molecule through a non-covalent approach. The non-imprinted polymer (NIP) was prepared following the same synthetic scheme, but in the absence of the template. The data obtained from scanning electronic microscopy, infrared spectroscopy, thermogravimetric and nitrogen Brunauer-Emmett-Teller plot helped to elucidate the structural as well as the morphological characteristics of the MIP and NIP. The application of MIP as a sorbent was demonstrated by packing it in solid phase extraction cartridges to extract fluconazole from commercial capsule samples through an offline analytical procedure. The quantification of fluconazole was accomplished through UPLC-MS, which resulted in LOD≤1.63×10(-10) mM. Furthermore, a high percentage recovery of 91±10% (n=9) was obtained. The ability of the MIP for selective recognition of fluconazole was evaluated by comparison with the structural analogues, miconazole, tioconazole and secnidazole, resulting in percentage recoveries of 51, 35 and 32%, respectively.

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The aim of this study was to develop a methodology using Raman hyperspectral imaging and chemometric methods for identification of pre- and post-blast explosive residues on banknote surfaces. The explosives studied were of military, commercial and propellant uses. After the acquisition of the hyperspectral imaging, independent component analysis (ICA) was applied to extract the pure spectra and the distribution of the corresponding image constituents. The performance of the methodology was evaluated by the explained variance and the lack of fit of the models, by comparing the ICA recovered spectra with the reference spectra using correlation coefficients and by the presence of rotational ambiguity in the ICA solutions. The methodology was applied to forensic samples to solve an automated teller machine explosion case. Independent component analysis proved to be a suitable method of resolving curves, achieving equivalent performance with the multivariate curve resolution with alternating least squares (MCR-ALS) method. At low concentrations, MCR-ALS presents some limitations, as it did not provide the correct solution. The detection limit of the methodology presented in this study was 50μgcm(-2).

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The aim of this research was to investigate the antiproliferative and anticholinesterase activities of 11 extracts from 5 Annonaceae species in vitro. Antiproliferative activity was assessed using 10 human cancer cell lines. Thin-layer chromatography and a microplate assay were used to screen the extracts for acetylcholinesterase (AchE) inhibitors using Ellman's reagent. The chemical compositions of the active extracts were investigated using high performance liquid chromatography. Eleven extracts obtained from five Annonaceae plant species were active and were particularly effective against the UA251, NCI-470 lung, HT-29, NCI/ADR, and K-562 cell lines with growth inhibition (GI50) values of 0.04-0.06, 0.02-0.50, 0.01-0.12, 0.10-0.27, and 0.02-0.04 µg/mL, respectively. In addition, the Annona crassiflora and A. coriacea seed extracts were the most active among the tested extracts and the most effective against the tumor cell lines, with GI50 values below 8.90 µg/mL. The A. cacans extract displayed the lowest activity. Based on the microplate assay, the percent AchE inhibition of the extracts ranged from 12 to 52%, and the A. coriacea seed extract resulted in the greatest inhibition (52%). Caffeic acid, sinapic acid, and rutin were present at higher concentrations in the A. crassiflora seed samples. The A. coriacea seeds contained ferulic and sinapic acid. Overall, the results indicated that A. crassiflora and A. coriacea extracts have antiproliferative and anticholinesterase properties, which opens up new possibilities for alternative pharmacotherapy drugs.

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In this work a simple and sensitive procedure to extract organic mercury from water and sediment samples, using methylene chloride in acidic media followed by CVAFS quantification has been developed. The method was evaluated for possible interferents, using different inorganic mercury species and humic acid, no effects being observed. The detection limit for organic mercury was 160 pg and 396 pg for water and sediment samples respectively. The accuracy of the method was evaluated using a certified reference material of methylmercury (BCR-580, estuarine sediment). Recovery tests using methylmercury as surrogate spiked with 1.0 up to 30.0 ng L-1 ranged from 90 up to 109% for water samples, whereas for sediments, recoveries ranged from 57 up to 97%.

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The aim of this work is to obtain, purify and characterize biochemically a peroxidase from Copaifera langsdorffii leaves (COP). COP was obtained by acetone precipitation followed by ion-exchange chromatography. Purification yielded 3.5% of peroxidase with the purification factor of 46.86. The COP optimum pH is 6.0 and the temperature is 35 ºC. COP was stable in the pH range of 4.5 to 9.3 and at temperatures below 50.0 ºC. The apparent Michaelis-Menten constants (Km) for guaiacol and H2O2 were 0.04 mM and 0.39 mM respectively. Enzyme turnover was 0.075 s-1 for guaiacol and 0.28 s-1 for hydrogen peroxide. Copaifera langsdorffii leaves showed to be a rich source of active peroxidase (COP) during the whole year. COP could replace HRP, the most used peroxidase, in analytical determinations and treatment of industrial effluents at low cost.