Search results for " chimica"
showing 10 items of 3438 documents
Synthesis of Rosmarinic Acid Amides as Antioxidative and Hypoglycemic Agents
2019
Type 2 diabetes mellitus (T2DM) is an important metabolic disorder for which there is an urgent need for new antidiabetic drugs. α-Glucosidase inhibition is an established protocol for T2DM therapy. Because hyperglycemia causes oxidative tissue damage, the development of agents with both α-glucosidase inhibition and antioxidant activity from natural or natural-derived polyphenols such derivatives of rosmarinic acid (RA) represents an attractive therapeutic option. We report a study on amides 1-10 derived from RA and their evaluation for yeast α-glucosidase inhibition and antioxidant activity (DPPH and ORAC tests). All amides showed higher inhibitory activity than that of RA, were by far mor…
PEG 400/Cerium Ammonium Nitrate Combined with Microwave-Assisted Synthesis for Rapid Access to Beta-Amino Ketones. An Easy-to-Use Protocol for Discov…
2018
Compound libraries are important requirement in target-based drug discovery. In the present work, a small focused compound library based on β-aminoketone scaffold has been prepared combining microwave-assisted organic synthesis (MAOS) with polymer-assisted solution phase synthesis (PASPS) and replacing reaction workup standard purification procedures with solid phase extraction (SPE). Specifically, the effects of solvent, such as dioxane, dimethylformamide (DMF), polyethylene glycol 400 (PEG 400), temperature, irradiation time, stoichiometric ratio of reagents, and catalysts (HCl, acetic acid, cerium ammonium nitrate (CAN)) were investigated to maximize both conversion and yield. The optimi…
A 3D‑scaffold of PLLA induces the morphological differentiation and migration of primary astrocytes and promotes the production of extracellular vesi…
2019
The present study analyzed the ability of primary rat astrocytes to colonize a porous scaffold, mimicking the reticular structure of the brain parenchyma extracellular matrix, as well as their ability to grow, survive and differentiate on the scaffold. Scaffolds were prepared using poly-L-lactic acid (PLLA) via thermally-induced phase separation. Firstly, the present study studied the effects of scaffold morphology on the growth of astrocytes, evaluating their capability to colonize. Specifically, two different morphologies were tested, which were obtained by changing the polymer concentration in the starting solution. The structures were characterized by scanning electron microscopy, and a…
3D cultures of primary astrocytes on Poly-L-lactic acid scaffolds
Tissue engineering is an emerging multidisciplinary field that aims at reproducing in vitro tissues with morphological and functional features similar to the biological tissue of the human body. Polymeric materials can be used in contact with biological systems in replacing destroyed tissue by transplantation [1]. Several biopolymers, including poly L (lactic acid) (PLLA), have been used in biomedical applications to set scaffolds with ductile proprieties and biodegradation kinetics [2]. In particular, the PLLA scaffold topography mimics the natural extracellular matrix and makes it a good candidate for neural tissue engineering. We report about of 3D system the PLLA porous scaffolds prepar…
3D Technology for the Artworks Handling
2022
In this study we present how to create a box for the transport of artworks put in place during the restauration of three polymateric sculpures made with trapanese technique called ‘Legno, Tela e Colla’. Thanks to 3D technology, we created a ‘digital twin’ of manufacts that allowed us to design and build supports and boxes for different uses. In this way, it was possible not to touch the artworks directly, so without risks for them, and to work even at a distance without the works, also in different places.
PLLA scaffolds with controlled architecture as potential microenvironment for in vitro tumor model
2019
Abstract The "microenvironment" where a tumor develops plays a fundamental role in determining its progression, the onset of metastasis and, eventually, its resistance to therapies. Tumor cells can be considered more or less invasive depending both on the nature of the cells and on the site where they are located. Commonly adopted laboratory culture protocols for the investigation of tumor cells take usually place on standard two-dimensional supports. However, such cultures do not allow for reproduction of the biophysical properties of the tumor’s microenvironment, thus causing the cells to lose most of their relevant characteristics. In this work MDA-MB 231 breast cancer cells were cultiva…
Ionic liquid crystals based on viologen dimers: tuning the mesomorphism by varying the conformational freedom of the ionic layer
2016
ABSTRACTWe investigated the liquid crystal behaviour of newly synthesised bistriflimide salts of symmetric viologen dimers. A smectic A phase was observed for intermediate spacer lengths and for relatively long lateral alkyl chains. The systems were characterised by thermal analysis, polarised optical microscopy, X-ray scattering and solid-state NMR. An intermediate ordered smectic phase was also exhibited by the compounds (except for systems with very short lateral chains) consisting of molten layers of alkyl chains and partially ordered ionic layers. These results, relating to the mesomorphic behaviour of viologen salts, are qualitatively compared to those of the more common imidazolium s…
NEW 4-DIAZOPYRAZOLE DERIVATIVES AS POTENTIAL ANTIBIOFILM AGENTS
2010
Many infections such as otitis media, sinusitis, cholesteatoma, tonsillitis and adenoiditis are caused by biofilm forming mucosal pathogens (P. aeruginosa, S. aureus, S. peneomoniae, H. influenzae and M. catarrhalis). Moreover, the role of biofilms in the chronic otolaryngologic infections has been recognized for otitis media, tonsillitis and rhinosinusitis. Finally, bacterial biofilms of S. aureus, S. epidermis and E. faecalis are the leading cause of medical device-related infections. Pathogens growing as biofilms are intrinsically resistant to conventional antibiotics and therefore the discovery of new compounds able to act against biofilm aggregated micro organisms is an urgent task. Pr…
Characterization of the Solid State Properties of Anodic Oxides on Magnetron Sputtered Ta, Nb and Ta-Nb Alloys
2012
Tantalum oxide, niobium oxide and Ta-Nb containing mixed oxides were grown by anodizing sputter-deposited Ta, Nb and Ta-Nb alloys of different compositions. A photoelectrochemical investigation was performed in order to estimate the band gap and the flat band potential of the oxides as a function of their composition. The band gap of the investigated Ta-Nb containing mixed oxides changed monotonically between those estimated for Ta2O5 (4.1 eV) and Nb2O5 (3.4 eV) and in agreement with a proposed correlation between the Band gap of an oxide and the difference of electronegativity of the oxide constituents. From the differential capacitance curves recorded in a wide range of electrode potentia…