TRPM2 Oxidation Activates Two Distinct Potassium Channels in Melanoma Cells through Intracellular Calcium Increase

Tumor microenvironments are often characterized by an increase in oxidative stress levels. We studied the response to oxidative stimulation in human primary (IGR39) or metastatic (IGR37) cell lines obtained from the same patient, performing patch-clamp recordings, intracellular calcium ([Ca²⁺]_i) imaging, and RT-qPCR gene expression analysis. In IGR39 cells, chloramine-T (Chl-T) activated large K⁺ currents (KROS) that were partially sensitive to tetraethylammonium (TEA). A large fraction of KROS was inhibited by paxilline—a specific inhibitor of large-conductance Ca²⁺-activated BK channels. The TEA-insensitive component was inhibited by senicapoc—a specific inhibitor of the Ca²⁺-activated KCa3.1 channel. Both BK and KCa3.1 activation were mediated by an increase in [Ca²⁺]_i induced by Chl-T. Both KROS and [Ca²⁺]_i increase were inhibited by ACA and clotrimazole—two different inhibitors of the calcium-permeable TRPM2 channel. Surprisingly, IGR37 cells did not exhibit current increase upon the application of Chl-T. Expression analysis confirmed that the genes encoding BK, KCa3.1, and TRPM2 are much more expressed in IGR39 than in IGR37. The potassium currents and [Ca²⁺]_i increase observed in response to the oxidizing agent strongly suggest that these three molecular entities play a major role in the progression of melanoma. Pharmacological targeting of either of these ion channels could be a new strategy to reduce the metastatic potential of melanoma cells, and could complement classical radio- or chemotherapeutic treatments.     

Green procedure for the preparation of scented alcohols from carbonyl compounds

Several alcohols--interesting as cosmetic fragrances whose main preparative route on an industrial scale or in the research laboratory is the reduction of the corresponding carbonyl compound--were obtained by a solvent-free methodology in a green chemistry context. The process involves the simple mixing of the carbonyl compound with sodium borohydride dispersed in wet alumina in the solid state; the conversions of the carbonyl compounds were obtained in good yields within short reaction times, without energy consumption. The following carbinols were studied: octan-3-ol, 2-cineolylols (endo-exo mixture), alpha-ionol, 4-methylbenzyl alcohol, 1-phenylethanol, trans-cinnamyl alcohol, p-anisyl alcohol, 4-phenyl-3-buten-2-ol.     

Proton NMR relaxation study of swelling and gelatinisation process in rice starch–water samples

Proton transverse magnetization decay curves of rice flour starch–water samples were measured and analysed for the presence of four components in the relaxation curve. T₂ values were interpreted on the basis of the diffusive and chemical exchange model that provided evidence for extra granular bulk water and three more water populations whose relaxation rate is governed by diffusive and chemical exchange with starch components. The analysis of relaxation data provided information on dynamics of water molecules as well as on the size and dispersion of diffusive domains. Furthermore, by measuring solid to liquid ratio, transverse and longitudinal relaxation curves of starch–water mixtures at increasing temperatures – from 20 to 77 °C – swelling and gelatinisation processes were monitored.     

CFD–DEM simulations of wet particles fluidization with a new evolution model for liquid bridge

A new model for liquid-bridge evolution with consideration of particle dynamics, is proposed to improve Computational Fluid Dynamics-Discrete Element Method (CFD–DEM) simulations of wet particles fluidization under high liquid loading and viscosity. A liquid bridge is allowed to form and remains stable only when the normal relative velocity of two particles is lower than a critical value v _nc. A large v _nc leads to an increase of liquid-bridge or cohesive force. The model can be reduced to the conventional liquid-bridge model in literature when v _nc = 0 or ∞. With the new model, the prediction of bubble properties including bubble center, aspect ratio, and volume agrees well with the experimental data in literature. In particular, under high liquid loading, bubble disintegration due to particle agglomerating is reasonably captured. The simulations demonstrate the advantage of the new model that can extend the liquid-bridge models and CFD–DEM for high liquid loading and viscosity.     

Scanning Probe Microscopy on heterogeneous CaCu<Subscript>3</Subscript>Ti<Subscript>4</Subscript>O<Subscript>12</Subscript> thin films

The conductive atomic force microscopy provided a local characterization of the dielectric heterogeneities in CaCu₃Ti₄O₁₂ (CCTO) thin films deposited by MOCVD on IrO₂ bottom electrode. In particular, both techniques have been employed to clarify the role of the inter- and sub-granular features in terms of conductive and insulating regions. The microstructure and the dielectric properties of CCTO thin films have been studied and the evidence of internal barriers in CCTO thin films has been provided. The role of internal barriers and the possible explanation for the extrinsic origin of the giant dielectric response in CCTO has been evaluated.     

Evaluation of the antioxidant properties and oxidative stability of Pecorino cheese made from the raw milk of ewes fed Rosmarinus officinalis L. leaves

The aim of this work was to study the effect of rosemary leaf dietary supplementation on the antioxidant activities and total phenolic content of Pecorino cheese. Three hundred and twenty‐four sheep were randomly assigned to two dietary groups, which received a standard diet based on lucerne hay and concentrate (400 g per day). The concentrate of the rosemary supplemented group contained 2.50% dried rosemary leaves. The trial lasted 7 weeks. Cheesemaking was performed 3, 5 and 7 weeks from the start of the trial. The Pecorino cheese antioxidant activity was modified by the diet. Rosemary supplementation increased the total phenolic content, enhanced the antioxidant properties and decreased the lipid oxidation of cheese. A slight decrease in flavour was detected in cheeses after 7 weeks of rosemary administration.     

Folic Acid Functionalized Surface Highlights 5‐Methylcytosine‐Genomic Content within Circulating Tumor Cells

Although the detection of methylated cell free DNA represents one of the most promising approaches for relapse risk assessment in cancer patients, the low concentration of cell‐free circulating DNA constitutes the biggest obstacle in the development of DNA methylation‐based biomarkers from blood. This paper describes a method for the measurement of genomic methylation content directly on circulating tumor cells (CTC), which could be used to deceive the aforementioned problem. Since CTC are disease related blood‐based biomarkers, they result essential to monitor tumor's stadiation, therapy, and early relapsing lesions. Within surface's bio‐functionalization and cell's isolation procedure standardization, the presented approach reveals a singular ability to detect high 5‐methylcytosine CTC‐subset content in the whole CTC compound, by choosing folic acid (FA) as transducer molecule. Sensitivity and specificity, calculated for FA functionalized surface (FA‐surface), result respectively on about 83% and 60%. FA‐surface, allowing the detection and characterization of early metastatic dissemination, provides a unique advance in the comprehension of tumors progression and dissemination confirming the presence of CTC and its association with high risk of relapse. This functionalized surface identifying and quantifying high 5‐methylcytosine CTC‐subset content into the patient's blood lead significant progress in cancer risk assessment, also providing a novel therapeutic strategy.     

Flux quantization effects in InN nanowires

InN nanowires, grown by plasma-enhanced molecular beam epitaxy, were investigated by means of magnetotransport. By performing temperature-dependent transport measurements and current measurements on a large number of nanowires of different dimensions, it is proven that the carrier transport mainly takes place in a tube-like surface electron gas. Measurements on three representative nanowires under an axially oriented magnetic field revealed pronounced magnetoconductance oscillations with a periodicity corresponding to a single magnetic flux quantum. The periodicity is explained by the effect of the magnetic flux penetrating the coherent circular quantum states in the InN nanowires, rather than by Aharonov-Bohm type interferences. The occurrence of the single magnetic flux quantum periodicity is attributed to the magnetic flux dependence of phase-coherent circular states with different angular momentum quantum numbers forming the one-dimensional transport channels. These phase coherent states can exist because of the almost ideal crystalline properties of the InN nanowires prepared by self-assembled growth.