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Olea europaea L. is the most valuable species of the Olea type, and its products offer a wide range of therapeutical uses. The olive tree has been extensively studied for its nourishing qualities, and the "Mediterranean diet", which includes virgin olive oil as a key dietary component, is strongly associated with a reduced risk of cardiovascular disease and various malignancies. Olive leaves, a by-product in the olive harvesting process, are valued as a resource for developing novel phytomedicines. For this purpose, two ethanolic extracts obtained from Olivae folium from Spain (OFS) and Greece (OFG) were investigated. Our findings contribute to a wider characterization of olive leaves. Both extracts displayed important amounts of phenolic compounds and pentacyclic triterpenes, OFG having higher concentrations of both polyphenols, such as oleuropein and lutein, as well as triterpenes, such as oleanolic acid and maslinic acid. The antioxidant capacity is similar for the two extracts, albeit slightly higher for OFG, possibly due to metal polyphenol complexes with antioxidant activity. The extracts elicited an antimicrobial effect at higher doses, especially against Gram-positive bacteria, such as Streptococcus pyogenes. The extract with lower inorganic content and higher content of polyphenols and triterpenic acids induced a strong anti-radical capacity, a selective cytotoxic effect, as well as antimigratory potential on A375 melanoma cells and antiangiogenic potential on the CAM. No irritability and a good tolerability were noted after evaluating the extracts on the in vivo Hen's Egg Test−Chorioallantoic Membrane (HET-CAM). Therefore, the present data are suggestive for the possible use of the two types of olive leaf products as high-antioxidant extracts, potentially impacting the healthcare system through their use as antimicrobial agents and as anticancer and anti-invasion treatments for melanoma. [ABSTRACT FROM AUTHOR]

This study demonstrated the capability of two readily available optical spectroscopy tools, namely UV-Vis absorption spectrophotometry and Raman/surface-enhanced Raman spectroscopy, to select in a rapid and noninvasive manner the most homogenous gold nanoparticle (AuNP) models and to identify their chemical binding mechanism to 2-thiouracil (2-TU). 2-TU is an anticancer drug of great promise in the antiproliferative and photothermal therapies of cancer. The citrate-capped AuNPs emerged as the most stable as well as time- and cost-effective AuNP model out of the three widely used colloidal nanocores (citrate-, borohydride-citrate-, and sodium dodecyl sulfate (SDS)-capped AuNPs) that were examined. 2-TU chemically attached to the relatively monodispersed AuNPs via a chemisorption mechanism. The 2-TU-AuNPs complex formed through the covalent bonding of the S atom of 2-TU to the nanosurface in a vertical orientation. The spectroscopic results were then confirmed with the help of density functional theory (DFT) calculations and other physicochemical characterization tools for nanomaterials such as transmission electron microscopy (TEM), dynamic light scattering (DLS), and zeta potential. Overall, the purified 2-TU-AuNPs were found to be spherical, had an average diameter of 25 ± 2 nm, a narrow size distribution (1–30 nm), a sharp localized surface plasmon resonance (LSPR) peak at 525 nm, and a negative surface charge (−14 mV). [ABSTRACT FROM AUTHOR]

The article offers information on the ongoing debate surrounding canonical literature and its relevance in contemporary education. Topics include the implications of evaluative judgments on canon formation, the conflict between conservators and relativists, and the role of popular culture in shaping literary preferences.

Herein, Raman and surface-enhanced Raman spectroscopies (SERS) were successfully employed to establish the chemical interactions of citrate-capped silver nanoparticles (AgNPs, 10–15 nm) with human red blood cells (RBCs). The Raman/SERS spectra offered spectral evidence for the cellular uptake of AgNPs and the subsequent change in the conformation of the most abundant component, hemoglobin (Hb), from oxyhemoglobin to deoxyhemoglobin. The spectral characterization of AgNPs' interactions with other RBC biomarkers (membrane proteins and lipids) was impeded by the dominant Hb bands, even for non-resonant Hb conditions. CytoViva hyperspectral imaging and graphite furnace atomic absorption spectroscopy (GFAAS) served as complementary tools to effectively address the challenges related to a single excitation line (632.8 nm) and the resolution of the confocal Raman microscope (0.5–1.0 µm). CytoViva confirmed the RBC-AgNP interactions through hyperspectral signatures and facilitated the label-free localization of AgNPs extracellularly and intracellularly. Irreversible agglutination of RBCs was noted after 24 h of exposure, raising concerns about the toxicity of AgNPs of biocompatible citrate coatings. GFAAS validated the Raman/SERS results by quantifying the proportion of AgNPs absorbed by RBCs, which was significant (~48% AgNPs by mass), mostly at the membrane (60% RBCs), and size dependent (no large AgNPs or AgNP-aggregates in RBCs, after 12–24 h). [ABSTRACT FROM AUTHOR]

Considering the aesthetic canon as a cultural construct or process that involves the whole cultural field, the concept is revisited nowadays in the spirit of World Literature theories. In this sense, there could be seen a rehabilitation of noncanonical genres or the circulation of values in the transnational space in order to cartography the (inter)national canon(s). The aim of this paper is to analyse a specific scene from the well-known Lewis Carroll novel Alice in Wonderland (translated into Romanian) from this premises: the instable place in the frames of noncanonical genres or categories and the relationships between literary prizes and the mechanism of canonization. [ABSTRACT FROM AUTHOR]

Although antimicrobial nanosilver finds numerous applications in the health and food industries, the in vivo toxicity of positively charged silver nanoparticles (AgNPs + ) and relevant controls are largely unexplored. This study investigates the relationship between the biodistribution and toxicity of the well-known cetyltrimethylammonium bromide (CTAB)-capped AgNPs + in 6-weeks old female Sprague-Dawley rats, at sublethal doses. Amounts comparative to those leaked from food products or considered for animal feed were administered through daily water intake, for an 18-day period: AgNPs + (40 μg mL -1 ), Ag + (40 μg mL -1 ), antimicrobial CTAB + (24 μg mL -1 ) and tap water. All exposures except for the water control had adverse effects on the health and systemic functions of rats (e.g., lethargy, hepatomegaly, splenomegaly, impediment of bone development, and/or heightened immune response). Although the total Ag accumulation in tissues (1.4-1.6 μg of Ag/g of liver, spleen, jejunum, and brain) was comparable for the two Ag species, AgNPs + were generally more toxic than Ag + , particularly in spleen (0.8 μg Ag/g). Significantly reduced euthanasia time, alopecia, inflammatory responses in spleen, fragile veins, and enhanced lymphocytosis were observed only for AgNPs + . Overall, this study raises health concerns about the ingestion of capped-AgNPs + or Ag + by first-hand consumers and industry workers., (Copyright © 2022 Elsevier Ltd. All rights reserved.)