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1.
Autoimmun Rev ; 23(5): 103533, 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38521214

ABSTRACT

Spondyloarthritis (SpA) is the most frequent extraintestinal manifestation in patients with inflammatory bowel diseases (IBD). When IBD and spondyloarthritis coexist, musculoskeletal and intestinal disease features should be considered when planning a therapeutic strategy. Treatment options for IBD and SpA have expanded enormously over the last few years, but randomized controlled trials with specific endpoints focused on SpA are not available in the IBD setting. To address this important clinical topic, the Italian Group for the Study of Inflammatory Bowel Disease (IG-IBD) and the Italian Society of Rheumatology (SIR) jointly planned to draw updated therapeutic recommendations for IBD-associated SpA using a pseudo-Delphi method. This document presents the official recommendations of IG-IBD and SIR on the management of IBD-associated SpA in the form of 34 statements and 4 therapeutic algorithms. It is intended to be a reference guide for gastroenterologists and rheumatologists dealing with IBD-associated SpA.

2.
Dermatology ; 2024 Mar 17.
Article in English | MEDLINE | ID: mdl-38493762

ABSTRACT

INTRODUCTION: Generalized pustular psoriasis (GPP) is a rare and chronic, debilitating skin condition characterised, in its acute flare phase, by clinically severe and potentially life-threatening systemic manifestations. Data on GPP are still scanty, particularly in Europe and at a national level. To provide expert indications on several disease-related and patient-related aspects of GPP, with specific focus to the Italian context. METHODS: We conducted an iterative eDelphi study following the recommended criteria for reporting methods and results. After a thorough bibliographic review aimed to identify unknown or controversial issues in GPP, the following areas were investigated through a few specific questions/statements for each area: 1) disease epidemiology; 2) disease characteristics, with specific interest towards GPP flares; 3) diagnosis and diagnostic delay; 4) GPP treatment; 5) GPP patient journey and use of healthcare resources in Italy; 6) unmet needs and quality of life. An Executive Board of 9 principal investigators revised and approved the topics to be examined and overviewed the whole project. A total of 35 experts from different Italian areas, including 34 board-certified Italian dermatologists and one representative of patients' associations, took part in the study. RESULTS: A high agreement in responses from Italian experts emerged during two eDelphi iterations on - among several other aspects - GPP prevalence and incidence in Italy, use of European Rare and Severe Psoriasis Expert Network diagnostic criteria, flare frequency and duration, best diagnostic and care pathway, and main unmet needs of Italian patients. On the other hand, a broad spectrum of treatments (of different drug classes) was reported both in the acute and chronic phases of GPP, and no consensus on the issue was thus achieved. CONCLUSIONS: Consensus findings from this Delphi study of GPP experts may be useful to fill gaps of knowledge and improve awareness of this rare disease, as well as to help clinical and public health management of GPP in Italy.

3.
J Appl Crystallogr ; 56(Pt 5): 1348-1360, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37791360

ABSTRACT

Model lipid bilayers have been widely employed as a minimal system to investigate the structural properties of biological membranes by small-angle X-ray (SAXS) and neutron scattering (SANS) techniques. These have nanometre resolution and can give information regarding membrane thickness and scattering length densities (SLDs) of polar and apolar regions. However, biological membranes are complex systems containing different lipids and protein species, in which lipid domains can be dynamically assembled and disassembled. Therefore, SLD variations can occur within the biomembrane. In this work, a novel method has been developed to simulate SAXS and SANS profiles obtained from large unilamellar vesicles containing SLD inhomogeneities that are spatially correlated over the membrane surface. Such inhomogeneities are represented by cylindrical entities with equivalent SLDs. Stacking of bilayers is also included in the model, with no correlation between horizontal and vertical order. The model is applied to a lipid bilayer containing SLD inhomogeneities representing pores, lipid domains, and transmembrane, partially immersed and anchored proteins. It is demonstrated that all the structural information from the host lipid bilayer and from the SLD inhomogeneity can be consistently retrieved by a combined analysis of experimental SAXS and SANS data through the methodology proposed here.

4.
ACS Appl Energy Mater ; 6(20): 10340-10353, 2023 Oct 23.
Article in English | MEDLINE | ID: mdl-37886223

ABSTRACT

Semitransparent perovskite solar cells (ST-PSCs) are increasingly important in a range of applications, including top cells in tandem devices and see-through photovoltaics. Transparent conductive oxides (TCOs) are commonly used as transparent electrodes, with sputtering being the preferred deposition method. However, this process can damage exposed layers, affecting the electrical performance of the devices. In this study, an indium tin oxide (ITO) deposition process that effectively suppresses sputtering damage was developed using a transition metal oxides (TMOs)-based buffer layer. An ultrathin (<10 nm) layer of evaporated vanadium oxide or molybdenum oxide was found to be effective in protecting against sputtering damage in ST-PSCs for tandem applications, as well as in thin perovskite-based devices for building-integrated photovoltaics. The identification of minimal parasitic absorption, the high work function and the analysis of oxygen vacancies denoted that the TMO layers are suitable for use in ST-PSCs. The highest fill factor (FF) achieved was 76%, and the efficiency (16.4%) was reduced by less than 10% when compared with the efficiency of gold-based PSCs. Moreover, up-scaling to 1 cm2-large area ST-PSCs with the buffer layer was successfully demonstrated with an FF of ∼70% and an efficiency of 15.7%. Comparing the two TMOs, the ST-PSC with an ultrathin V2Ox layer was slightly less efficient than that with MoOx, but its superior transmittance in the near infrared and greater light-soaking stability (a T80 of 600 h for V2Ox compared to a T80 of 12 h for MoOx) make V2Ox a promising buffer layer for preventing ITO sputtering damage in ST-PSCs.

5.
Nanoscale ; 15(37): 15196-15205, 2023 Sep 29.
Article in English | MEDLINE | ID: mdl-37624640

ABSTRACT

Guanine (G) hydrogels are very attractive materials made by the supramolecular organization of G-derivatives in water. In this paper, hydrogels composed of guanosine 5'-monophosphate (GMP) and guanosine (Gua), that make long, flexible and knotted G-quadruplexes, were investigated by small- and wide-angle X-ray scattering (SAXS and WAXS) to comprehend the origin of their unique orientational properties. The SAXS intensity, analysed at a fixed scattering vector modulus Q as a function of polar angle, allowed us to derive the Maier-Saupe orientation parameter m. The strong dependence of m on hydrogel composition and temperature demonstrated that the preferred orientation is controlled by the quadruplex surface charge and flexibility. Indeed, a possible correlation between the orientation parameter m and the quadruplex-to-quadruplex lateral interactions was explored. Results confirmed that the balance between attractive and repulsive interactions plays a main role in the orientational anisotropy: quadruplex clusters lose their orientational properties when attractive interactions decrease. The key role of the number of negative charges per unit length of the G-quadruplex filaments was confirmed by Atomic Force Microscopy (AFM) observations. Indeed, directionality histograms showed that in the presence of a large amount of Gua, G-quadruplexes follow preferential orientations other than those related to the strong interactions with the K+ pattern on the mica surface. The fact that lateral quadruplex-to-quadruplex interactions, even in the presence of external (opposing) forces, can tune the hydrogel alignment in a given preferred direction provides novel possibilities for scaffold/3D printing applications.

6.
Analyst ; 148(18): 4365-4372, 2023 Sep 11.
Article in English | MEDLINE | ID: mdl-37548234

ABSTRACT

Raman MicroSpectroscopy (RMS) is a powerful label-free tool to probe the effects of drugs at a cellular/subcellular level. It is important, however, to be able to extract relevant biochemical and kinetic spectroscopic signatures of the specific cellular responses. In the present study, a combination of Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) and Principal Component Analysis (PCA) is used to analyse the RMS data for the example of exposure of primary Oral Squamous Carcinoma Cells (OSCC) to the chemotherapeutic agent cisplatin. Dosing regimens were established by cytotoxicity assays, and the effects of the drug on cellular spectral profiles were monitored from 16 to 72 hours post-exposure using an apoptosis assay, to establish the relative populations of viable (V), early (EA) and late apoptotic/dead (LA/D) cells after the drug treatment. Based on a kinetic model of the progression from V > EA > D, MCR-ALS regression analysis of the RMS responses was able to extract spectral profiles associated with each stage of the cellular responses, enabling a quantitative comparison of the response rates for the respective drug treatments. Moreover, PCA was used to compare the spectral profiles of the viable cells exposed to the drug. Spectral differences were highlighted in the early stages (16 hours exposure), indicative of the initial cellular response to the drug treatment, and also in the late stages (48-72 hours exposure), representing the cell death pathway. The study demonstrates that RMS coupled with multivariate analysis can be used to quantitatively monitor the progression of cellular responses to different drugs, towards future applications for label-free, in vitro, pre-clinical screening.


Subject(s)
Carcinoma, Squamous Cell , Cisplatin , Humans , Cisplatin/pharmacology , Least-Squares Analysis , Spectrum Analysis, Raman/methods , Carcinoma, Squamous Cell/drug therapy , Multivariate Analysis
7.
Int J Mol Sci ; 24(7)2023 Mar 23.
Article in English | MEDLINE | ID: mdl-37047038

ABSTRACT

The main protease (Mpro or 3CLpro) is an enzyme that is evolutionarily conserved among different genera of coronaviruses. As it is essential for processing and maturing viral polyproteins, Mpro has been identified as a promising target for the development of broad-spectrum drugs against coronaviruses. Like SARS-CoV and MERS-CoV, the mature and active form of SARS-CoV-2 Mpro is a dimer composed of identical subunits, each with a single active site. Individual monomers, however, have very low or no catalytic activity. As such, inhibition of Mpro can be achieved by molecules that target the substrate binding pocket to block catalytic activity or target the dimerization process. In this study, we investigated GC376, a transition-state analog inhibitor of the main protease of feline infectious peritonitis coronavirus, and Nirmatrelvir (NMV), an oral, bioavailable SARS-CoV-2 Mpro inhibitor with pan-human coronavirus antiviral activity. Our results show that both GC376 and NMV are capable of strongly binding to SARS-CoV-2 Mpro and altering the monomer-dimer equilibrium by stabilizing the dimeric state. This behavior is proposed to be related to a structured hydrogen-bond network established at the Mpro active site, where hydrogen bonds between Ser1' and Glu166/Phe140 are formed in addition to those achieved by the latter residues with GC376 or NMV.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , SARS-CoV-2/metabolism , Cysteine Endopeptidases/metabolism , Protease Inhibitors/pharmacology , Protease Inhibitors/chemistry , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Molecular Docking Simulation
8.
Intern Emerg Med ; 18(3): 831-842, 2023 04.
Article in English | MEDLINE | ID: mdl-36882619

ABSTRACT

Acid sphingomyelinase deficiency (ASMD) is an ultra-rare disease, and several gaps of knowledge on various issues remain, particularly at a regional/national level. Expert opinions collected through well-defined consensus methodologies are increasingly used to make available reliable information in the context of rare/ultra-rare diseases. With the aim to provide indications on infantile neurovisceral ASMD (also formerly known as Niemann-Pick disease type A), chronic neurovisceral ASMD (formerly known as Niemann-Pick disease type A/B) and chronic visceral ASMD (formerly known as Niemann-Pick disease type B) in Italy, we conducted a Delphi consensus of experts focused on five main areas: (i) patients and disease characteristics; (ii) unmet needs and quality of life; (iii) diagnostic issues; (iv) treatment-related aspects; and (v) patient journey. Pre-specified, objective criteria were used to outline the multidisciplinary panel, based on 19 Italian experts in ASMD in paediatric and adult patients from different Italian Regions, including both clinicians (n = 16) and ASMD patients' advocacy or payors with expertise in rare diseases (n = 3). During two Delphi rounds, a high ratio of agreement was found on several topics related to ASMD characteristics, diagnosis, management and disease burden. Our findings may provide valuable indications for management of ASMD at a public health level in Italy.


Subject(s)
Niemann-Pick Disease, Type A , Niemann-Pick Diseases , Adult , Humans , Child , Niemann-Pick Disease, Type A/diagnosis , Sphingomyelin Phosphodiesterase , Quality of Life , Consensus , Rare Diseases , Delphi Technique , Italy
9.
Gels ; 9(2)2023 Jan 26.
Article in English | MEDLINE | ID: mdl-36826277

ABSTRACT

In the present study, gels based on xanthan gum and poloxamer 407 have been developed and characterized in order to convey natural antioxidant molecules included in niosomes. Specifically, the studies were conducted to evaluate how the vesicular systems affect the release of the active ingredient and which formulation is most suitable for cutaneous application. Niosomes, composed of Span 20 or Tween 20, were produced through the direct hydration method, and therefore, borate buffer or a micellar solution of poloxamer 188 was used as the aqueous phase. The niosomes were firstly characterized in terms of morphology, dimensional and encapsulation stability. Afterwards, gels based on poloxamer 407 or xanthan gum were compared in terms of spreadability and adhesiveness. It was found to have greater spreadability for gels based on poloxamer 407 and 100% adhesiveness for those based on xanthan gum. The in vitro diffusion of drugs studied using Franz cells associated with membranes of mixed cellulose esters showed that the use of a poloxamer micellar hydration phase determined a lower release as well as the use of Span 20. The thickened niosomes ensured controlled diffusion of the antioxidant molecules. Lastly, the in vivo irritation test confirmed the safeness of niosomal gels after cutaneous application.

10.
Int J Mol Sci ; 23(23)2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36499432

ABSTRACT

In this study, the transdermal fate of vesicular nanosystems was investigated. Particularly, ethosomes based on phosphatidylcholine 0.9% w/w and transethosomes based on phosphatidylcholine 0.9 or 2.7% w/w plus polysorbate 80 0.3% w/w as an edge activator were prepared and characterized. The vesicle mean size, morphology and deformability were influenced by both phosphatidylcholine and polysorbate 80. Indeed, the mean diameters of ethosome were around 200 nm, while transethosome's mean diameters were 146 or 350 nm in the case of phosphatidylcholine 0.9 or 2.7%, w/w, respectively. The highest deformability was achieved by transethosomes based on phosphatidylcholine 0.9%, w/w. The three types of vesicular nanosystems were applied on explanted human skin maintained in a bioreactor. Transmission electron microscopy demonstrated that all vesicles were able to enter the skin, keeping their structural integrity. Notably, the vesicle penetration capability was influenced by their physical-chemical features. Indeed, ethosomes reached keratinocytes and even the dermis, phosphatidylcholine 0.9% transethosomes were found in keratinocytes and phosphatidylcholine 2.7% transethosomes were found only in corneocytes of the outer layer. These findings open interesting perspectives for a differentiated application of these vesicles for transdermal drug delivery as a function of the cutaneous pathology to be addressed.


Subject(s)
Drug Carriers , Skin Absorption , Humans , Drug Carriers/chemistry , Skin/metabolism , Administration, Cutaneous , Phosphatidylcholines/metabolism , Liposomes/chemistry
11.
J Colloid Interface Sci ; 624: 579-592, 2022 Oct 15.
Article in English | MEDLINE | ID: mdl-35690012

ABSTRACT

Rhamnolipids (RLs) are biosurfactants with significant tensioactive and emulsifying properties. They are mainly composed by mono-RL and di-RL components. Although there are numerous studies concerning their molecular properties, information is scarce regarding the mechanisms by which each of the two components interacts with cell membranes. Herein, we performed phase-contrast and fluorescence microscopy experiments on plasma membrane models represented by giant-unilamellar-vesicles (GUVs) composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), 2-[[(E,2S,3R)-1,3-dihydroxy-2-(octadecanoylamino) octadec-4-enyl]peroxy-hydroxyphosphoryl]oxyethyl-trimethylazanium (sphingomyelin, SM) and (3ß)-cholest-5-en-3-ol (cholesterol, CHOL) (1:1:1 M ratio), which present liquid-order (Lo) liquid-disorder (Ld) phase coexistence, in the presence of either mono-RL or di-RL in 0.06-0.25 mM concentration range. A new method has been developed to determine area and volume of GUVs with asymmetrical shape and a kinetic model describing GUV-RL interaction in terms of two mechanisms, RL-insertion and pore formation, has been worked out. Results show that the insertion of mono-RL in the membrane outer leaflet is the dominant process with no pore formation and a negligible effect in modifying membrane permeability, but induces lipid mixing. Conversely, the di-RL-GUV interaction begins with the insertion mechanism and, as the time passes by, the pore formation process occurs. The analyses of di-RL show that the whole process is only relevant in the Ld phase with a higher extent to 0.25 mM than to 0.06 mM.


Subject(s)
Sphingomyelins , Unilamellar Liposomes , Cell Membrane , Decanoates , Glycolipids , Lipid Bilayers , Phosphatidylcholines , Rhamnose/analogs & derivatives
12.
Biomedicines ; 10(5)2022 May 23.
Article in English | MEDLINE | ID: mdl-35625944

ABSTRACT

Pancreatic cancer has a high morbidity and mortality with the majority being PC ductal adenocarcinomas (PDAC). Whole genome sequencing provides a wide description of genomic events involved in pancreatic carcinogenesis and identifies putative biomarkers for new therapeutic approaches. However, currently, there are no approved treatments targeting driver mutations in PDAC that could produce clinical benefit for PDAC patients. A proportion of 5-10% of PDAC have a hereditary origin involving germline variants of homologous recombination genes, such as Mismatch Repair (MMR), STK11 and CDKN2A genes. Very recently, BRCA genes have been demonstrated as a useful biomarker for PARP-inhibitor (PARPi) treatments. In this study, a series of 21 FFPE PDACs were analyzed using OncoPan®, a strategic next-generation sequencing (NGS) panel of 37 genes, useful for identification of therapeutic targets and inherited cancer syndromes. Interestingly, this approach, successful also on minute pancreatic specimens, identified biomarkers for personalized therapy in five PDAC patients, including two cases with HER2 amplification and three cases with mutations in HR genes (BRCA1, BRCA2 and FANCM) and potentially eligible to PARPi therapy. Molecular analysis on normal tissue identified one PDAC patient as a carrier of a germline BRCA1 pathogenetic variant and, noteworthy, this patient was a member of a family affected by inherited breast and ovarian cancer conditions. This study demonstrates that the OncoPan® NGS-based panel constitutes an efficient methodology for the molecular profiling of PDAC, suitable for identifying molecular markers both for therapy and risk assessment. Our data demonstrate the feasibility and utility of these NGS analysis in the routine setting of PDAC molecular characterization.

13.
Life (Basel) ; 12(1)2022 Jan 15.
Article in English | MEDLINE | ID: mdl-35054516

ABSTRACT

Many proteins are usually not stable under different stresses, such as temperature and pH variations, mechanical stresses, high concentrations, and high saline contents, and their transport is always difficult, because they need to be maintained in a cold regime, which is costly and very challenging to achieve in remote areas of the world. For this reason, it is extremely important to find stabilizing agents that are able to preserve and protect proteins against denaturation. In the present work, we investigate, by extensively using synchrotron small-angle X-ray scattering experiments, the stabilization effect of five different sugar-derived compounds developed at ExtremoChem on two model proteins: myoglobin and insulin. The data analysis, based on a novel method that combines structural and thermodynamic features, has provided details about the physical-chemical processes that regulate the stability of these proteins in the presence of stabilizing compounds. The results clearly show that some modified sugars exert a greater stabilizing effect than others, being able to maintain the active forms of proteins at temperatures higher than those in which proteins, in the absence of stabilizers, reach denatured states.

14.
Nanomaterials (Basel) ; 12(2)2022 Jan 11.
Article in English | MEDLINE | ID: mdl-35055245

ABSTRACT

Herpes simplex virus type 1 infection commonly affects many people, causing perioral sores, as well as severe complications including encephalitis in immunocompromised patients. The main pharmacological approach involves synthetic antiviral drugs, among which acyclovir is the golden standard, often leading to resistant virus strains under long-term use. An alternative approach based on antiviral plant-derived compounds, such as quercetin and mangiferin, demonstrated an antiviral potential. In the present study, semisolid forms for cutaneous application of quercetin and mangiferin were designed and evaluated to treat HSV-1 infection. Phosphatidylcholine- and poloxamer-based gels were produced and characterized. Gel physical-chemical aspects were evaluated by rheological measurements and X-ray diffraction, evidencing the different thermoresponsive behaviors and supramolecular organizations of semisolid forms. Quercetin and mangiferin diffusion kinetics were compared in vitro by a Franz cell system, demonstrating the different gel efficacies to restrain the polyphenol diffusion. The capability of gels to control polyphenol antioxidant potential and stability was evaluated, indicating a higher stability and antioxidant activity in the case of quercetin loaded in poloxamer-based gel. Furthermore, a plaque reduction assay, conducted to compare the virucidal effect of quercetin and mangiferin loaded in gels against the HSV-1 KOS strain, demonstrated the suitability of poloxamer-based gel to prolong the polyphenol activity.

15.
Nanomaterials (Basel) ; 12(2)2022 Jan 14.
Article in English | MEDLINE | ID: mdl-35055282

ABSTRACT

An optimization work on dye-sensitized solar cells (DSSCs) based on both artificial and natural dyes was carried out by a fine synthesis work embedding gold nanoparticles in a TiO2 semiconductor and perfecting the TiO2 particle sizes of the scattering layer. Noble metal nanostructures are known for the surface plasmon resonance peculiarity that reveals unique properties and has been implemented in several fields such as sensing, photocatalysis, optical antennas and PV devices. By embedding gold nanoparticles in the mesoporous TiO2 layer and adding a scattering layer, we were able to boost the power conversion efficiency (PCE) to 10.8%, using an organic ruthenium complex. The same implementation was carried out using a natural dye, betalains, extracted from Sicilian prickly pear. In this case, the conversion efficiency doubled from 1 to 2% (measured at 1 SUN illumination, 100 mW/cm2 under solar simulation irradiation). Moreover, we obtained (measured at 0.1 SUN, 10 mW/cm2 under blue light LED irradiation) a record efficiency of 15% with the betalain-based dye, paving the way for indoor applications in organic natural devices. Finally, an attempt to scale up the system is shown, and a betalain-based- dye-sensitized solar module (DSSM), with an active area of 43.2 cm2 and a PCE of 1.02%, was fabricated for the first time.

16.
Colloids Surf B Biointerfaces ; 209(Pt 1): 112171, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34736221

ABSTRACT

The use of glyceryl monooleate (GMO)-based nanoparticles has not yet been explored in overcoming the low bioavailability of Epigallocatechin-3-gallate (EGCG), a green tea polyphenol with a known anticancer activity. Since the inclusion of a guest molecule can affect the curvature and the supramolecular structure of fully hydrated GMO-based phase, the phase behavior of bulk and dispersed liquid crystalline systems containing EGCG were explored by Small Angle Neutron Scattering and X-Ray Diffraction experiments. Molecular Dynamic Simulations showed how the interaction of EGCG with polar heads of GMO strongly affects the curvature and packing of GMO phase. The EGCG encapsulation efficiency was determined in the nanodispersions and their size studied by Dynamic Light Scattering and Atomic Force Microscopy. A nanodispersed formulation has been optimized with a cytotoxic effect more than additive of GMO and EGCG.


Subject(s)
Catechin , Catechin/analogs & derivatives , Glycerides , Tea
17.
Materials (Basel) ; 14(19)2021 Sep 23.
Article in English | MEDLINE | ID: mdl-34639901

ABSTRACT

Nanocluster aggregation sources based on magnetron-sputtering represent precise and versatile means to deposit a controlled quantity of metal nanoparticles at selected interfaces. In this work, we exploit this methodology to produce Ag/MgO nanoparticles (NPs) and deposit them on a glass/FTO/TiO2 substrate, which constitutes the mesoscopic front electrode of a monolithic perovskite-based solar cell (PSC). Herein, the Ag NP growth through magnetron sputtering and gas aggregation, subsequently covered with MgO ultrathin layers, is fully characterized in terms of structural and morphological properties while thermal stability and endurance against air-induced oxidation are demonstrated in accordance with PSC manufacturing processes. Finally, once the NP coverage is optimized, the Ag/MgO engineered PSCs demonstrate an overall increase of 5% in terms of device power conversion efficiencies (up to 17.8%).

18.
Pharmaceutics ; 13(8)2021 Jul 23.
Article in English | MEDLINE | ID: mdl-34452085

ABSTRACT

Human skin is dramatically exposed to toxic pollutants such as ozone. To counteract the skin disorders induced by the air pollution, natural antioxidants such as mangiferin could be employed. A formulative study for the development of vesicular systems for mangiferin based on phosphatidylcholine and the block copolymer pluronic is described. Plurethosomes were designed for mangiferin transdermal administration and compared to ethosome and transethosome. Particularly, the effect of vesicle composition was investigated on size distribution, inner and outer morphology by photon correlation spectroscopy, small angle X-ray diffraction, and transmission electron microscopy. The potential of selected formulations as vehicles for mangiferin was studied, evaluating encapsulation efficiency and in vitro diffusion parameters by Franz cells. The mangiferin antioxidant capacity was verified by the 2,2-diphenyl-1-picrylhydrazyl assay. Vesicle size spanned between 200 and 550 nm, being influenced by phosphatidylcholine concentration and by the presence of polysorbate or pluronic. The vesicle supramolecular structure was multilamellar in the case of ethosome or plurethosome and unilamellar in the case of transethosome. A linear diffusion of mangiferin in the case of ethosome and transethosomes and a biphasic profile in the case of plurethosomes indicated the capability of multilamellar vesicles to retain the drug more efficaciously than the unilamellar ones. The antioxidant and anti-inflammatory potential effect of mangiferin against pollutants was evaluated on 3D human skin models exposed to O3. The protective effect exerted by plurethosomes and transethosomes suggests their possible application to enhance the cutaneous antioxidant defense status.

19.
ACS Appl Mater Interfaces ; 13(19): 22368-22380, 2021 May 19.
Article in English | MEDLINE | ID: mdl-33969983

ABSTRACT

Carbon perovskite solar cells (C-PSCs), using carbon-based counter electrodes (C-CEs), promise to mitigate instability issues while providing solution-processed and low-cost device configurations. In this work, we report the fabrication and characterization of efficient paintable C-PSCs obtained by depositing a low-temperature-processed graphene-based carbon paste atop prototypical mesoscopic and planar n-i-p structures. Small-area (0.09 cm2) mesoscopic C-PSCs reach a power conversion efficiency (PCE) of 15.81% while showing an improved thermal stability under the ISOS-D-2 protocol compared to the reference devices based on Au CEs. The proposed graphene-based C-CEs are applied to large-area (1 cm2) mesoscopic devices and low-temperature-processed planar n-i-p devices, reaching PCEs of 13.85 and 14.06%, respectively. To the best of our knowledge, these PCE values are among the highest reported for large-area C-PSCs in the absence of back-contact metallization or additional stacked conductive components or a thermally evaporated barrier layer between the charge-transporting layer and the C-CE (strategies commonly used for the record-high efficiency C-PSCs). In addition, we report a proof-of-concept of metallized miniwafer-like area C-PSCs (substrate area = 6.76 cm2, aperture area = 4.00 cm2), reaching a PCE on active area of 13.86% and a record-high PCE on aperture area of 12.10%, proving the metallization compatibility with our C-PSCs. Monolithic wafer-like area C-PSCs can be feasible all-solution-processed configurations, more reliable than prototypical perovskite solar (mini)modules based on the serial connection of subcells, since they mitigate hysteresis-induced performance losses and hot-spot-induced irreversible material damage caused by reverse biases.

20.
Sci Rep ; 11(1): 9283, 2021 04 29.
Article in English | MEDLINE | ID: mdl-33927258

ABSTRACT

The maturation of coronavirus SARS-CoV-2, which is the etiological agent at the origin of the COVID-19 pandemic, requires a main protease Mpro to cleave the virus-encoded polyproteins. Despite a wealth of experimental information already available, there is wide disagreement about the Mpro monomer-dimer equilibrium dissociation constant. Since the functional unit of Mpro is a homodimer, the detailed knowledge of the thermodynamics of this equilibrium is a key piece of information for possible therapeutic intervention, with small molecules interfering with dimerization being potential broad-spectrum antiviral drug leads. In the present study, we exploit Small Angle X-ray Scattering (SAXS) to investigate the structural features of SARS-CoV-2 Mpro in solution as a function of protein concentration and temperature. A detailed thermodynamic picture of the monomer-dimer equilibrium is derived, together with the temperature-dependent value of the dissociation constant. SAXS is also used to study how the Mpro dissociation process is affected by small inhibitors selected by virtual screening. We find that these inhibitors affect dimerization and enzymatic activity to a different extent and sometimes in an opposite way, likely due to the different molecular mechanisms underlying the two processes. The Mpro residues that emerge as key to optimize both dissociation and enzymatic activity inhibition are discussed.


Subject(s)
Antiviral Agents/chemistry , COVID-19/metabolism , Coronavirus 3C Proteases/chemistry , Protease Inhibitors/chemistry , SARS-CoV-2/physiology , Antiviral Agents/pharmacology , COVID-19/therapy , Computational Biology , Coronavirus 3C Proteases/genetics , Coronavirus 3C Proteases/metabolism , Dimerization , Drug Discovery , Humans , Molecular Docking Simulation , Protease Inhibitors/pharmacology , Protein Binding , Protein Conformation , Thermodynamics , X-Ray Diffraction
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