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1.
J Mass Spectrom ; 57(8): e4878, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36065819

ABSTRACT

The evolution of the regulatory framework for medical devices in the EU (Reg 2017/745) has opened the study of complex systems emerging properties. This makes necessary to identify new analytical approaches able of characterizing complex natural substrates as completely as possible. Therefore, omics approaches and advanced analytical methods for the determination of metabolite classes appear to be at the forefront to meet this need. In this perspective, a new approach based on the suspect screening was developed to detect gallotannins. Gallotannins are a class of phenols with a polymeric nature; thus, there are no pure analytical standards available for all possible structures and their quali-quantitative determination in complex natural substrates can be a challenge. A new UHPLC-qToF method was developed and used to create an "in-house tannin database" with a dual purpose: (1) as a classic list of suspects and (2) to identify core fragments common to gallotannins to have another list of putative suspects based on the common fragment. The method was validated. The application of the method to a "system of molecules" extracted from the leaves of Hamamelis virginiana L. (Witch-hazel) allowed to the characterization of a total of 29 phenols by a suspect screening approach. Therefore, 15 gallotannins were putatively annotated while another 3 were confidently identified. All the gallotannins were semiquantified according to external regression curves of gallic acid and hamamelitannin based on core fragments at m/z 125.0244 and m/z 169.0142, the building blocks of the polymers. This new method provides a practical fit-to-purpose approach for the quali-quantitative screening evaluation of gallotannins, useful for creating multivariate control charts applicable in process development of complex natural systems or in quality control. The approach is innovative, and after specific checks, it can in principle be suitable for metabolomic fingerprint analysis of gallotannins among witch-hazel extract (WHE) samples.


Subject(s)
Hamamelis , Hydrolyzable Tannins , Chromatography, High Pressure Liquid/methods , Hamamelis/chemistry , Hydrolyzable Tannins/chemistry , Metabolomics , Phenols/chemistry
2.
Nutrients ; 12(6)2020 May 31.
Article in English | MEDLINE | ID: mdl-32486519

ABSTRACT

Current pharmacological therapies for the management of chronic articular diseases are far from being satisfactory, so new strategies need to be investigated. We tested the intra-articular pain relieving properties of a system of molecules from a characterized Centella asiatica extract (14G1862) in a rat model of osteoarthritis induced by monoiodoacetate (MIA). 14G1862 (0.2-2 mg mL-1) was intra-articularly (i.a.) injected 7 days after MIA, behavioural and histological evaluations were performed 14, 30 and 60 days after treatments. Moreover, the effect of 14G1862 on nitrate production and iNOS expression in RAW 264.7 macrophages stimulated with LPS was assessed. In vitro, 14G1862 treatment attenuated LPS-induced NO production and iNOS expression in a comparable manner to celecoxib. In vivo, 14G1862 significantly reduced mechanical allodynia and hyperalgesia, spontaneous pain and motor alterations starting on day 14 up to day 60. The efficacy was higher or comparable to that evoked by triamcinolone acetonide (100 µg i.a.) used as reference drug. Histological evaluation highlighted the improvement of several morphological parameters in MIA + 14G1862-treated animals with particularly benefic effects on joint space and fibrin deposition. In conclusion, i.a. treatment with Centella asiatica is a candidate to be a novel effective approach for osteoarthritis therapy.


Subject(s)
Analgesics/therapeutic use , Centella/chemistry , Injections, Intra-Articular/methods , Pain/drug therapy , Triterpenes/therapeutic use , Analgesics/pharmacology , Animals , Arthritis, Experimental/chemically induced , Arthritis, Experimental/drug therapy , Cell Survival/drug effects , Disease Models, Animal , Hyperalgesia/drug therapy , Iodoacetic Acid , Macrophages/drug effects , Male , Mice , Nitrates/metabolism , Nitric Oxide Synthase Type II/metabolism , Osteoarthritis/drug therapy , Osteoarthritis, Knee/drug therapy , Pain Management , Plant Extracts , RAW 264.7 Cells , Rats , Rats, Sprague-Dawley , Triterpenes/pharmacology
3.
Appl Opt ; 50(18): 2836-45, 2011 Jun 20.
Article in English | MEDLINE | ID: mdl-21691346

ABSTRACT

In this paper, the results of the thermo-elastic analysis performed on the stereo channel of the imaging system Integrated Observatory System for the BepiColombo European Space Agency mission to Mercury are presented. The aim of the work is to determine the effects of ambient parameter variations on the equipment performance; the optical performance is changing during the mission lifetime primarily because of the optics misalignments and deformations induced by temperature variations. The camera optics and their mountings are modeled and processed by a thermo-mechanical finite element model (FEM) program, which reproduces the expected optics and structure thermo-elastic deformations in the instrument foreseen operative temperature range, i.e., between -20 °C and 30 °C. The FEM outputs are elaborated using a MATLAB optimization routine: an algorithm based on nonlinear least square data fitting is adopted to determine the surface equation (plane, spherical, nth polynomial) which best fits the deformed optical surfaces. The obtained surfaces are then directly imported into a ZEMAX code for sequential ray-tracing analysis. Variations of the optical spot diagrams, modulation transfer function curves, and ensquared energy are then computed. The overall analysis shows that the preferred solution for mounting the optical elements is adopting the kinematic constraints instead of using the classical glue solution.

4.
Science ; 317(5845): 1715-8, 2007 Sep 21.
Article in English | MEDLINE | ID: mdl-17885128

ABSTRACT

Mars' polar regions are covered with ice-rich layered deposits that potentially contain a record of climate variations. The sounding radar SHARAD on the Mars Reconnaissance Orbiter mapped detailed subsurface stratigraphy in the Promethei Lingula region of the south polar plateau, Planum Australe. Radar reflections interpreted as layers are correlated across adjacent orbits and are continuous for up to 150 kilometers along spacecraft orbital tracks. The reflectors are often separated into discrete reflector sequences, and strong echoes are seen as deep as 1 kilometer. In some cases, the sequences are dipping with respect to each other, suggesting an interdepositional period of erosion. In Australe Sulci, layers are exhumed, indicating recent erosion.


Subject(s)
Mars , Extraterrestrial Environment , Ice
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