Search results for "Spectroscopy"
showing 10 items of 10293 documents
Evidences on alterations in skeleton composition and mineralization in a site-attached fish under naturally acidified conditions in a shallow CO2 vent
2021
Abstract Background Ocean acidification may affect fish mineralized structures (i.e. otoliths and skeleton). Methods Here, we compared the elemental composition of muscle and skeleton and the mineral features of skeleton in the site-attached fish Gobius bucchichi naturally exposed to high pCO2/low pH conditions in a shallow CO2 vent with fish of the same species exposed to normal pH. Results Overall, no skeleton malformations were found in both pH conditions, but among-site differences were found in the elemental composition. Interestingly, higher Ca/P values, inducing a moderate skeleton maturation, were found in fish exposed to acidified conditions than in controls. Conclusion Our finding…
Indoor spectroradiometric characterization of plastic litters commonly polluting the Mediterranean Sea: toward the application of multispectral image…
2020
AbstractAround 350 million tonnes of plastics are annually produced worldwide. A remarkable percentage of these products is dispersed in the environment, finally reaching and dispersed in the marine environment. Recent field surveys detected microplastics’ concentrations in the Mediterranean Sea. The most commonly polymers found were polyethylene, polypropylene and viscose, ethylene vinyl acetate and polystyrene. In general, the in-situ monitoring of microplastic pollution is difficult and time consuming. The main goals of this work were to spectrally characterize the most commonly polymers and to quantify their spectral separability that may allow to determine optimal band combinations for…
The Chaperone System in Breast Cancer: Roles and Therapeutic Prospects of the Molecular Chaperones Hsp27, Hsp60, Hsp70, and Hsp90
2022
Breast cancer (BC) is a major public health problem, with key pieces of information needed for developing preventive and curative measures still missing. For example, the participation of the chaperone system (CS) in carcinogenesis and anti-cancer responses is poorly understood, although it can be predicted to be a crucial factor in these mechanisms. The chief components of the CS are the molecular chaperones, and here we discuss four of them, Hsp27, Hsp60, Hsp70, and Hsp90, focusing on their pro-carcinogenic roles in BC and potential for developing anti-BC therapies. These chaperones can be targets of negative chaperonotherapy, namely the elimination/blocking/inhibition of the chaperone(s)…
The Chaperone System in Salivary Glands: Hsp90 Prospects for Differential Diagnosis and Treatment of Malignant Tumors
2022
Salivary gland tumors represent a serious medical problem and new tools for differential diagnosis and patient monitoring are needed. Here, we present data and discuss the potential of molecular chaperones as biomarkers and therapeutic targets, focusing on Hsp10 and Hsp90. The salivary glands are key physiological elements but, unfortunately, the information and the means available for the management of their pathologies, including cancer, are scarce. Progress in the study of carcinogenesis has occurred on various fronts lately, one of which has been the identification of the chaperone system (CS) as a physiological system with presence in all cells and tissues (including the salivary gland…
Structural and Dynamic Disturbances Revealed by Molecular Dynamics Simulations Predict the Impact on Function of CCT5 Chaperonin Mutations Associated…
2023
Mutations in genes encoding molecular chaperones, for instance the genes encoding the subunits of the chaperonin CCT (chaperonin containing TCP-1, also known as TRiC), are associated with rare neurodegenerative disorders. Using a classical molecular dynamics approach, we investigated the occurrence of conformational changes and differences in physicochemical properties of the CCT5 mutations His147Arg and Leu224Val associated with a sensory and a motor distal neuropathy, respectively. The apical domain of both variants was substantially but differently affected by the mutations, although these were in other domains. The distribution of hydrogen bonds and electrostatic potentials on the surfa…
Ciprofloxacin Polymers Derived from Diallyltin and Divinyltin Dihalides
2008
The initial synthesis of condensation polymers from newly available divinyltin dichloride and diallyltin dichloride and ciprofloxacin is accomplished employing a modified interfacial polycondensation process. The polymeric (DP are about 2,000) products are rapidly (less than 15 seconds) formed in good yield. Infrared spectroscopy shows the formation of Sn-O and Sn-N bonds as predicted from the proposed structure. F-MALDI MS also shows ion fragments containing organotin in the predicted isotopic abundances as well as ion fragments containing both organotin and ciprofloxacin. The polymers exhibit low toxicity towards healthy WI-38 cells with variable toxicities towards a variety of cancer cel…
G4-DNA vs. B-DNA binding of Schiff base transition metal complexes
2014
The competitive binding of nickel(II), copper(II) and zinc(II) complexes toward B- and G4-DNA was addressed through spectroscopic titrations and rationalized by computational investigations, consisting of molecular dynamics simulations followed by density functional theory/molecular mechanics (DFT/MM) calculations [1]. The experimental DNA binding studies clearly highlight the selectivity of the compounds, in particular the nickel(II) complex, toward G4-DNA from both h-Telo and c-myc. Moreover, the compounds show biological activity against HeLa and MCF-7 cancer cell lines. Remarkably, the experimental DNA-binding affinity trend of the three metal complexes, obtained from the DNA-binding co…
DNA-Binding of NiII, CuII and ZnII Complexes of Salen Derivatives
2014
Nickel(II), copper(II) and zinc(II) complexes of N2O2 tetradentate Schiff base ligands strongly interact with B-DNA, usually by groove-binding and/or by intercalation [1]. It has been also shown that the presence of aromatic substituents on the N,N’ bridge make them suitable G-quadruplex binders [2]. In this context, we have recently investigated the binding toward duplex and G-quadruplex DNA of nickel(II), copper(II) and zinc(II) complexes of N,N’-bis-5-(triethyl ammonium methyl)-salicylidene-2,3-naphthalendiiminato) (see Figure), by spectroscopic and computational methods [3,4]. The compounds show also biological activity against human cancer cell lines. Different substituents are present…
Dissolution of nitrones in alkylphosphates: A structural study
2022
Nitrones are chemical compounds with well-established anti-oxidant and spin-trapping properties. Their low solubility in water for many of them limits their applications, so opportune solvents must be found. In this study, two recently synthetized oxindole nitrones with proven antiproliferative and antioxidant activity have been dissolved in several liquid amphiphiles, chosen as model solvents. The effect of the polar head nature and the alkyl chain length/type have been investigated by a combined experimental (solubility, UV–vis spectroscopy) / computational (molecular dynamics) approach. The different chemical structures of the various solvents offer different chemical environments to the…
MICROSCOPIC TECHNIQUES AND A MULTI-ANALYTICAL APPROACH TO CHARACTERIZE THE MATERIALS OF TWO RUSSIAN ICONS
2018
Two 19th century Russian icons, from the Museo Diocesano of Palermo, were analysed by UV photography, X-ray fluorescence, energy-dispersive X-ray fluorescence (ED-XRF), optical microscopy, micro-Raman spectroscopy and Scanning Electron Microscopy, combined with energy dispersive x-ray analysis, (SEM/EDS). The multi-analytical study of the icons “Protezione della Madre di Dio” (Pokrov’s Icon, Protection of Holy Mother of God) and ‘’Madre di Dio Gioia di Tutti gli Afflitti’’, (Holy Mother of God, Joy of all the afflicted), have been performed to reveal materials and technological features of the original painting of the 19th century as well as the materials used during past restoration works.…