100 research outputs found

    Environmentally Friendly Sunscreens: Mechanochemical Synthesis and Characterization of β-CD Inclusion Complexes of Avobenzone and Octinoxate with Improved Photostability

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    We report on the mechanochemical synthesis of inclusion complexes obtained by reacting β-cyclodextrin (β-CD) with two widely used sunscreens, namely, avobenzone (AVO) and octinoxate (OCT). Formation of crystalline inclusion complexes was confirmed via a combination of solid-state techniques, including X-ray diffraction (XRD), Raman, and ATR-FTIR spectroscopies. A new, metastable polymorph of avobenzone was also isolated and characterized. NMR spectroscopy and thermal analyses (TGA and DSC) allowed us to evaluate the host/guest ratio and the water content (ca. 8H2O) in crystalline (β-CD)2·AVO and (β-CD)3·OCT2. Photodegradation of the two sunscreens upon inclusion in the hydrophobic cavity of β-CD was evaluated in solution via mass spectrometry (ESI-MS) and UV-vis spectroscopy and found to be sharply reduced. All findings indicate that the inclusion of AVO and OCT in β-CD might represent a viable route for the preparation of environmentally friendly sunscreens with improved photostability to be used in formulations of sun creams

    Assembling photoactive materials from polycyclic aromatic hydrocarbons (PAHs): room temperature phosphorescence and excimer-emission in co-crystals with 1,4-diiodotetrafluorobenzene

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    Co-crystallization between the polycyclic aromatic hydrocarbons anthracene (A) and 9-methylanthracene (MA) with 1,4-diiodotetrafluorobenzene (I2F4) afforded three novel co-crystals, viz. A·(I2F4)2 and an unexpectedly complex system with two distinct compositions, namely MA·I2F4 and (MA)4·I2F4, which can be mechanochemically interconverted by a change in the stoichiometry of the reactive mixtures. Interestingly, all co-crystals are dual-emissive materials and exhibit different mechanisms of emission. A·(I2F4)2 and MA·I2F4 fluoresce from isolated molecules, whereas the luminescence of (MA)4·I2F4 is dominated by excimer emission. In all cases, phosphorescence at RT (RTP) is observed and interpreted as a direct consequence of the interactions between the iodine atoms of the I2F4 co-former and the π-electron density of the anthracene aromatic rings. Furthermore, [4 + 4] photoactivity within (MA)4·I2F4 was also investigated by means of FTIR/NMR spectroscopy and PXRD. The photophysical and photochemical behaviors of all solids are discussed and rationalized based on their structural features

    Chronic administration of green tea extract to TRAMP mice induces the collapse of Golgi apparatus in prostate secretory cells and results in alterations of protein post-translational processing.

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    Considering its long latency, prostate cancer (PCa) represents an ideal target for chemoprevention strategies. Green tea extract (GTE) has been proved to be one of the most promising natural substances capable of inhibiting PCa progression in animal models (transgenic adenocarcinoma of mouse prostate), as well as in humans. However, the cellular targets of the GTE action are mostly unknown. The main objective of this work was to investigate whether the endoplasmic reticulum (ER) and the Golgi apparatus (GA), known to be actively involved in sensing stress stimuli and initiating and propagating cell death signalling, may represent the subcellular targets of GTE action. To this end, 42 TRAMP mice were divided into four experimental groups: groups II and IV, received GTE in tap water (0.3 g/100 ml solution) starting at 8 weeks of age and up to the time of sacrifice. Groups I and III were respective age-matched water-fed controls. The animals were sacrificed after 4 weeks (groups I and II) or 40 weeks of treatment (groups II and IV). We also treated TRAMP-C2 cells with GTE (20 µg/ml for 7 days) to check the expression profile of clusterin (CLU), a protein involved in prostate tumourigenesis, extensively processed through ER-GA before being secreted through the plasma membrane. In vivo we found that chronic administration of GTE in TRAMP mice results in collapse of ER and GA in prostate epithelial cells. Consistently, in vitro we found that the mature, fully processed form of CLU, sCLU, is strongly reduced by GTE treatment in TRAMP-C2 cells. Taking into account the sCLU biogenesis dependence on the ER-GA integrity and the proposed anti-apoptotic role of sCLU, the possibility for GTE to counteract PCa progression by interfering with sCLU biogenesis is suggested

    Early Detection and Investigation of Extracellular Vesicles Biomarkers in Breast Cancer

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    Breast cancer (BC) is the most commonly diagnosed malignant tumor in women worldwide, and the leading cause of cancer death in the female population. The percentage of patients experiencing poor prognosis along with the risk of developing metastasis remains high, also affecting the resistance to current main therapies. Cancer progression and metastatic development are no longer due entirely to their intrinsic characteristics, but also regulated by signals derived from cells of the tumor microenvironment. Extracellular vesicles (EVs) packed with DNA, RNA, and proteins, are the most attractive targets for both diagnostic and therapeutic applications, and represent a decisive challenge as liquid biopsy-based markers. Here we performed a study based on a multiplexed phenotyping flow cytometric approach to characterize BC-derived EVs from BC patients and cell lines, through the detection of multiple antigens. Our data reveal the expression of EVs-related biomarkers derived from BC patient plasma and cell line supernatants, suggesting that EVs could be exploited for characterizing and monitoring disease progression

    Endocanalicular transendothelial crossing (ETC): A novel intravasation mode used by HEK-EBNA293-VEGF-D cells during the metastatic process in a xenograft model

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    In cancer metastasis, intravasation of the invasive tumor cell (TCi) represents one of the most relevant events. During the last years, models regarding cancer cell intravasation have been proposed, such as the "endocanalicular transendothelial crossing" (ETC) theory. This theory describes the interplay between two adjacent endothelial cells and the TCi or a leukocyte during intravasation. Two endothelial cells create a channel with their cell membranes, in which the cell fits in without involving endothelial cell intercellular junctions, reaching the lumen through a transendothelial passage. In the present study, ten SCID mice were subcutaneously xenotransplanted with the HEK-EBNA293-VEGF-D cell line and euthanized after 35 days. Post-mortem examinations were performed and proper specimens from tumors were collected. Routine histology and immunohistochemistry for Ki-67, pAKT, pERK, ZEB-1, TWIST-1, F-actin, E-cadherin and LYVE-1 were performed followed by ultrastructural serial sections analysis. A novel experimental approach involving Computed Tomography (CT) combined with 3D digital model reconstruction was employed. The analysis of activated transcription factors supports that tumor cells at the periphery potentially underwent an epithelial-to-mesenchymal transition (EMT)-like process. Topographical analysis of LYVE-1 immunolabeled lymphatics revealed a peritumoral localisation. TEM investigations of the lymphatic vessels combined with 3D digital modelling enhanced the understanding of the endotheliocytes behavior during TCi intravasation, clarifying the ETC theory. Serial ultrastructural analysis performed within tumor periphery revealed numerous cells during the ETC process. Furthermore, this study demonstrates that ETC is an intravasation mode more frequently used by the TCi than by leukocytes during intravasation in the HEK-EBNA293-VEGF-D xenograft model and lays down the potential basis for promising future studies regarding intravasation blocking therapy

    L^2 rho form for normal coverings of fibre bundles

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    We define the secondary invariants L^2- eta and -rho forms for families of generalized Dirac operators on normal coverings of fibre bundles. On the covering family we assume transversally smooth spectral projections, and Novikov--Shubin invariants bigger than 3(dim B+1) to treat the large time asymptotic for general operators. In the particular case of a bundle of spin manifolds, we study the L^2- rho class in relation to the space of positive scalar curvature vertical metrics.Comment: 21 pages, revised versio

    A multi-element psychosocial intervention for early psychosis (GET UP PIANO TRIAL) conducted in a catchment area of 10 million inhabitants: study protocol for a pragmatic cluster randomized controlled trial

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    Multi-element interventions for first-episode psychosis (FEP) are promising, but have mostly been conducted in non-epidemiologically representative samples, thereby raising the risk of underestimating the complexities involved in treating FEP in 'real-world' services
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