Development of 'Redox Arrays' for identifying novel glutathionylated proteins in the secretome

Proteomics techniques for analysing the redox status of individual proteins in complex mixtures tend to identify the same proteins due to their high abundance. We describe here an array-based technique to identify proteins undergoing glutathionylation and apply it to the secretome and the proteome of human monocytic cells. The method is based on incorporation of biotinylated glutathione (GSH) into proteins, which can then be identified following binding to a 1000-protein antibody array. We thus identify 38 secreted and 55 intracellular glutathionylated proteins, most of which are novel candidates for glutathionylation. Two of the proteins identified in these experiments, IL-1 sRII and Lyn, were then confirmed to be susceptible to glutathionylation. Comparison of the redox array with conventional proteomic methods confirmed that the redox array is much more sensitive, and can be performed using more than 100-fold less protein than is required for methods based on mass spectrometry. The identification of novel targets of glutathionylation, particularly in the secretome where the protein concentration is much lower, shows that redox arrays can overcome some of the limitations of established redox proteomics techniques

Trace Elements in Soil and Urban Groundwater in an Area Impacted by Metallurgical Activity: Health Risk Assessment in the Historical Barga Municipality (Tuscany, Italy)

Trace elements were measured in soil and groundwater collected within the Fornaci di Barga urban area (Serchio River Valley, Tuscany, Italy), a territory that integrates natural assets with touristic vocation, impacted by long-lasting metallurgical activity. Epidemiological studies highlighted that the area surrounding the industrial plants is characterized by a persistent excess of diseases, attributed to heavy metal pollution. Soils were taken in school gardens, public parks, sport grounds and roadsides. The results indicate that Cu, Zn and Cd represent the main contaminants in surface soil, likely originated by deposition of airborne particulate matter from metallurgical activity. Risk assessment considering soil ingestion and dermal contact exposure routes revealed that the cadmium Hazard Quotient approaches unity for children, and the cadmium risk-based concentration obtained by combining exposure information with toxicity data is only slightly lower compared with the cadmium maximum concentration actually measured in soil. Groundwater does not show evidence of trace metal contamination, suggesting that the migration of contaminants from soil to subsurface is a slow process. However, assessment of the possible interconnections between shallow and deep-seated aquifers requires monitoring to be continued. The obtained results highlight the possible link between space clusters of diseases and metal concentration in soil

Evaporite Dissolution Rate through an on-site Experiment into Piezometric Tubes Applied to the Real Case-Study of Quinis (NE Italy)

The present paper deals with a field experiments on evaporite rock samples and groundwater investigations in the Quinis test site, a hamlet of the Enemonzo municipality in NE Italy, were sinkholes occurred in the past and are still occurring causing severe damage to the existing infrastructures. The area is characterised by a Carnian evaporitic bedrock made of gypsum and anhydrite mantled by alluvial and colluvial deposits. In order to evaluate the loss of weight and volume of the subcropping evaporites as responsible for sinkholes, a field-experiment was carried out. Inside seven piezometers, at dierent depths, evaporitic rock samples were exposed to the naturally occurring variable climatic conditions such as degree of humidity, dierent air flow and hydrodynamic. The rock samples were installed at the beginning of April 2017 in the dry sections of piezometric tubes, in the vadose zone and in the phreatic zone. Data related to water level fluctuations were recorded by using data-logger devices and highlight significant changes in the water table. After 13 months of data recording (May 2018), rock samples were removed, reweighted and the volume loss measured. In addition, water from piezometer-experiment, representative of the groundwater circulation, were collected at dierent depths. The obtained results indicate that rock sample reduction is dependent on the hydrological regime and water chemistry and not on the number of days during which the samples remained submersed. In particular, the water geochemistry highlights the possible role in gypsum/anhydrite dissolution due to NaCl water admixing in a complex scenario. In additional, the geochemical data highlight the occurrence of some potentially toxic elements (As, Fe, Mn) at concentrations of concern in some water. This approach represents a novel contribution in the study of karst hazard in evaporites adding a tile to the knowledge of the fast evolutionary processes which cause sinkhole formation

Evaporite Dissolution Rate through an on-site Experiment into Piezometric Tubes Applied to the Real Case-Study of Quinis (NE Italy)

The present paper deals with a field experiments on evaporite rock samples and groundwater investigations in the Quinis test site, a hamlet of the Enemonzo municipality in NE Italy, were sinkholes occurred in the past and are still occurring causing severe damage to the existing infrastructures. The area is characterised by a Carnian evaporitic bedrock made of gypsum and anhydrite mantled by alluvial and colluvial deposits. In order to evaluate the loss of weight and volume of the subcropping evaporites as responsible for sinkholes, a field-experiment was carried out. Inside seven piezometers, at different depths, evaporitic rock samples were exposed to the naturally occurring variable climatic conditions such as degree of humidity, different air flow and hydrodynamic. The rock samples were installed at the beginning of April 2017 in the dry sections of piezometric tubes, in the vadose zone and in the phreatic zone. Data related to water level fluctuations were recorded by using data-logger devices and highlight significant changes in the water table. After 13 months of data recording (May 2018), rock samples were removed, reweighted and the volume loss measured. In addition, water from piezometer-experiment, representative of the groundwater circulation, were collected at different depths. The obtained results indicate that rock sample reduction is dependent on the hydrological regime and water chemistry and not on the number of days during which the samples remained submersed. In particular, the water geochemistry highlights the possible role in gypsum/anhydrite dissolution due to NaCl water admixing in a complex scenario. In additional, the geochemical data highlight the occurrence of some potentially toxic elements (As, Fe, Mn) at concentrations of concern in some water. This approach represents a novel contribution in the study of karst hazard in evaporites adding a tile to the knowledge of the fast evolutionary processes which cause sinkhole formation

Thermal behavior study of pristine and modified halloysite nanotubes: A modern kinetic study

Pristine halloysite nanotubes (HNTs) were studied by thermogravimetry (TG) up to 800 C. Etching of alumina from inside the tube (causing a significant increase in tube lumen) was realized by treating the material with an acidic H2SO4 solution at 50 C. Both materials were characterized by TG-FTIR techniques and their thermal behaviors were compared with that of kaolinite. The coupling of TG with FTIR enables to detect the gases evolved during the TG experiments, thus confirming that only pristine HNTs undergo dehydration with the loss of interlayer water molecules at around 245 C, while dehydroxylation occurs in all these materials in close temperature ranges around 500 C. TG runs at five different heating rates (2, 5, 10, 15 and 20 C min-1), was carried out in the same experimental conditions used for the thermal analysis study with the aim to investigate dehydration and dehydroxylation kinetics using some isoconversional methods recommended by the ICTAC kinetic committee, and thermogravimetric data under a modulated rising temperature program. Finally, the results of the kinetic analysis were discussed and explained in terms of the strengths of the hydrogen bonds broken during these processes

Influence of environmental and anthropogenic parameters on thallium oxidation state in natural waters

The abandoned mining area of Valdicastello Carducci (Tuscany, Italy) is characterized by the massive presence of thallium in the acid mine drainages and in the valley stream crossing the region. We previously found that Tl(III), generally considered the less stable oxidation state of thallium, is present both in the stream and in tap water distributed in the area, whereas acid mine drainages only contain Tl(I). These findings posed some concern related to the reactivity and dispersion of this toxic element in the environment. Since the valence state of thallium determines its toxicity, distribution and mobility, the study of thallium redox speciation appears crucial to understand its environmental behaviour. In this work, water samples collected from the mine drainages and the contaminated stream were adopted as model to study the distribution of aqueous Tl(I)/Tl(III) as a function of light exposure and solution properties and composition. The influence of three light sources and organic acids was evaluated. Thallium speciation was also assessed in tap water after treatment with common oxidizing agents, and in the rust crust collected from the public waterworks

Genipin diffusion and reaction into a gelatin matrix for tissue engineering applications

Genipin is a natural low-toxic cross-linker for molecules with primary amino groups, and its use with collagen and gelatin has shown a great potential in tissue engineering applications. The fabrication of scaffolds with a well-organized micro and macro topology using additive manufacturing systems requires an accurate control of working parameters, such as reaction rate, gelling time, and diffusion constant. A polymeric system of 5% w/v gelatin in PBS with 2 mg/mL collagen solutions in a 1:1 weight ratio was used as template to perform measurements varying genipin concentration in a range of 0.1-1.5% w/w with respect to gelatin. In the first part of this work, the reaction rate of the polymeric system was estimated using a new colorimetric analysis of the reaction. Then its workability time, closely related to the gelling time, was evaluated thanks to rheological analysis: finally, the quantification of static and dynamic diffusion constants of genipin across nonreacting and reacting membranes, made respectively by agarose and gelatin, was performed. It was shown that the colorimetric analysis is a good indicator of the reaction progress. The gelling time depends on the genipin concentration, but a workability window of 40 min guaranteed up to 0.5% w/w genipin. The dynamic diffusion constant of genipin in the proposed polymeric system is in the order of magnitude of 10(-7) . The obtained results indicated the possibility to use the genipin, gelatin, and collagen, in the proposed concentrations, to build well-defined hydrogel scaffolds with both extrusion-based and 3D ink-jet system. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2015

Geochemical characterization of recent Nile Delta inner shelf sediments: Tracing natural and human-induced alterations into a deltaic system

Abstract The present study deals with the geochemical changes observed along Nile Delta inner shelf sediments over a period of 20 years (1995–2015). Major, minor, and trace constituents as well as rare earth elements (REE) were investigated in the surface sediments collected from seven transects along the inner shelf on five years intervals. Geochemical composition of sediments in Nile Delta inner shelf exhibits continuous changes over time due to the depositional and sediment transport processes. The sediments are generally enriched with Fe and Ti oxides, as well as Ta, Nb, Y in comparison to the Upper Continental Crust (UCC). These alterations signify the impact of processes such as erosion and sediment transport, as well as the impact of anthropogenic interferences such as damming the Nile River Flow. The reduction of the sediment input from the Nile River has somehow altered the geochemical signature of the inner shelf sediments. The REE patterns indicate weathering in areas subjected to erosion, while trace elements and major oxides spatial and temporal distributions concentrate eastwards under the influence of the easterly sediment transport pattern. Nile Delta inner shelf presented a typical case for understanding the link between geochemistry and sedimentary processes in nearshore and deltaic systems

Interactions between inorganic pigments and rabbit skin glue in reference paint reconstructions

The thermal degradation of rabbit skin glue, a collagen-based proteinaceous material used as a paint binder in paintings, was investigated in this paper. Paint reconstructions of the glue on its own or mixed with azurite (Cu3(CO3)2(OH)2), calcium carbonate (CaCO3), hematite (Fe2O3nH2O) and red lead (Pb3O4) were analysed using a thermoanalytical approach. This method enabled us to investigate the interactions between the glue and pigments before and after artificial indoor light ageing. The study was carried out using differential scanning calorimetry, thermogravimetry and thermogravimetry/FTIR analysis already successfully employed to characterize the paint binders. The results highlighted that all the inorganic pigments interact with rabbit skin glue, thus decreasing the thermal stability of the binder. Light ageing further decreased the thermal stability of pigmented paint replicas, suggesting a moderate increase in the rate of the degradation

Pharmacology and clinical drug candidates in redox medicine

SIGNIFICANCE Oxidative stress is suggested to be a disease mechanism common to a wide range of disorders affecting human health. However, so far, the pharmacotherapeutic exploitation of this, for example, based on chemical scavenging of pro-oxidant molecules, has been unsuccessful. Recent Advances: An alternative emerging approach is to target the enzymatic sources of disease-relevant oxidative stress. Several such enzymes and isoforms have been identified and linked to different pathologies. For some targets, the respective pharmacology is quite advanced, that is, up to late-stage clinical development or even on the market; for others, drugs are already in clinical use, although not for indications based on oxidative stress, and repurposing seems to be a viable option. CRITICAL ISSUES For all other targets, reliable preclinical validation and drug ability are key factors for any translation into the clinic. In this study, specific pharmacological agents with optimal pharmacokinetic profiles are still lacking. Moreover, these enzymes also serve largely unknown physiological functions and their inhibition may lead to unwanted side effects. FUTURE DIRECTIONS The current promising data based on new targets, drugs, and drug repurposing are mainly a result of academic efforts. With the availability of optimized compounds and coordinated efforts from academia and industry scientists, unambiguous validation and translation into proof-of-principle studies seem achievable in the very near future, possibly leading towards a new era of redox medicine