Environmentally Friendly Method of Assembly of Cardanol and Cholesterol into Nanostructures Using a Continuous Flow Microfluidic Device

This study shows a viable and straightforward microfluidic method of assembly of cardanol (CA) and cholesterol (CH) into amphiphile nanostructures obtained through a hydrodynamic focusing approach according to which an alcoholic solution of CA and CH is constrained within a two-dimensional lamina shape by two lateral streams of borate buffer solution. The process is performed within glass-made cross-shaped micro-sized fluidic chips specially designed to achieve a laminar regime. CA, distilled from the cashew nut shell liquid, is demonstrated as a surface-active molecule in borate buffer basic medium and when mixed with CH it produces versatile nanovesicles through an in-batch solvent-free process. Compared to this conventional method, the microfluidic route allows operating under continuous flows, with a reduced amount of reagents and at lower experimental temperatures, ensuring no waste formation and the achievement of size-monodisperse amphiphile nanostructures that do not need further steps of purification. Electron microscopy analyses demonstrate that upon increasing CH in the lipid mixture, a switchover from spherical CA micelles to CA/CH mixed closed vesicles occurs. Differential scanning microcalorimetry confirms the formation of vesicular structures and evidences the primary role of CH, which increasingly lowers the temperature of transition depending on its concentration

Mixing enhancement induced by viscoelastic micromotors in microfluidic platforms

Fine manipulation of fluid flows at the microscale has a tremendous impact on mass transport phenomena of chemical and biological processes inside microfluidic platforms. Fluid mixing in the laminar flow regime at low Reynolds number is poorly effective due to the inherently slow diffusive mechanism. As a strategy to enhance mixing and prompt mass transport, here, we focus on polyelectrolyte multilayer capsules (PMCs), embodying a catalytic polyoxometalate, as microobjects to create elastic turbulence and as micromotors to generate chaotic flows by fuel-fed propulsions. The effects of the elastic turbolence and of the artificial propulsion on some basic flow parameters, such as pressure and volumetric flow rate, are studied by a microfluidic set-up including pressure and flow sensors. Numerical-handling and physical models of the experimental data are presented and discussed to explain the measured dependence of the pressure drop on the flow rate in presence of the PMCs. As a practical outcome of the study, a strong decrease of the mixing time in a serpentine microreactor is demonstrated. Unlike our previous reports dealing with capillarity flow studies, the present paper relies on hydrodynamic pumping experiments, that allow us to both develop a theoretical model for the understanding of the involved phenomena and demonstrate a successful microfluidic mixing application. All of this is relevant in the perspective of developing microobject-based methods to overcome microscale processes purely dominated by diffusion with potential improvements of mass trasport in microfluidic platforms. \ua9 2019 Elsevier B.V

Catalytic oxygen production mediated by smart capsules to modulate elastic turbulence under a laminar flow regime

none11Liquid flow in microchannels is completely laminar and uniaxial, with a very low Reynolds number regime and long mixing lengths. To increase fluid mixing and solubility of reactants, as well as to reduce reaction time, complex three-dimensional networks inducing chaotic advection have to be designed. Alternatively, turbulence in the liquid can be generated by active mixing methods (magnetic, acoustic waves, etc.) or adding small quantities of elastic materials to the working liquid. Here, polyelectrolyte multilayer capsules embodying a catalytic polyoxometalate complex have been suspended in an aqueous solution and used to create elastic turbulence and to propel fluids inside microchannels as an alternative to viscoelastic polymers. The overall effect is enhanced and controlled by feeding the polyoxometalate-modified capsules with hydrogen peroxide, H2O2, thus triggering an on-demand propulsion due to oxygen evolution resulting from H2O2 decomposition. The quantification of the process is done by analysing some structural parameters of motion such as speed, pressure, viscosity, and Reynolds and Weissenberg numbers, directly obtained from the capillary dynamics of the aqueous mixtures with different concentrations of H2O2. The increases in fluid speed as well as the capsule-induced turbulence effects are proportional to the H2O2 added and therefore dependent on the kinetics of H2O2 dismutation.Zizzari A.; Bianco M.; Miglietta R.; del Mercato L. L.; Carraro M.; Soraru A.; Bonchio M.; Gigli G.; Rinaldi R.; Viola I.; Arima, V.Zizzari, A.; Bianco, M.; Miglietta, R.; del Mercato, L. L.; Carraro, M.; Soraru, A.; Bonchio, M.; Gigli, Giuseppe; Rinaldi, Rosaria; Viola, I.; Arima, V

Changes in matrix extracellular phosphoglycoprotein expression before and during in vitro osteogenic differentiation of human dental papilla mesenchymal cells.

The purpose of this study is to characterise the expression of matrix extracellular phosphoglycoprotein (MEPE) in cultured mesenchymal cells isolated from human dental papilla (PaMCs) of impacted third molars either before or during differentiation of these cells into osteo/odontoblasts. PaMCs, like mesenchymal cells deriving from human dental pulp (DPMCs), resulted positive for a number of mesenchymal markers including CD146 and STRO-1. During the first week in culture they showed a faster proliferation rate than DPMCs, coupled to an earlier down-regulation of MEPE. Also when the cells were further cultured in osteogenic medium (containing β-glycerophosphate, ascorbic acid and dexamethasone) for 40 days, MEPE down-regulation coupled to an increased expression of osteogenic markers, such as osteocalcin and alkaline phosphatase, occurred earlier in PaMCs than in DPMCs. Thus, our data, indicating that also in PaMCs MEPE expression is higher when cells proliferate, whereas it is downregulated as cells differentiated, are in favour of a role of MEPE as an early regulator of odontogenic differentiation. We also confirm the superior proliferative potential of PaMCs in comparison with DPMCs, coupled to a more rapid induction of osteogenic differentiation. Therefore, these cells represent an optimal source to be conveniently used for dental tissue engineering and tooth regeneration

Long-Lasting Metabolic Imbalance Related to Obesity Alters Olfactory Tissue Homeostasis and Impairs Olfactory-Driven Behaviors.

Obesity is associated with chronic food intake disorders and binge eating. Food intake relies on the interaction between homeostatic regulation and hedonic signals among which, olfaction is a major sensory determinant. However, its potential modulation at the peripheral level by a chronic energy imbalance associated to obese status remains a matter of debate. We further investigated the olfactory function in a rodent model relevant to the situation encountered in obese humans, where genetic susceptibility is juxtaposed on chronic eating disorders. Using several olfactory-driven tests, we compared the behaviors of obesity-prone Sprague-Dawley rats (OP) fed with a high-fat/high-sugar diet with those of obese-resistant ones fed with normal chow. In OP rats, we reported 1) decreased odor threshold, but 2) poor olfactory performances, associated with learning/memory deficits, 3) decreased influence of fasting, and 4) impaired insulin control on food seeking behavior. Associated with these behavioral modifications, we found a modulation of metabolism-related factors implicated in 1) electrical olfactory signal regulation (insulin receptor), 2) cellular dynamics (glucorticoids receptors, pro- and antiapoptotic factors), and 3) homeostasis of the olfactory mucosa and bulb (monocarboxylate and glucose transporters). Such impairments might participate to the perturbed daily food intake pattern that we observed in obese animals

Nitric Oxide-mediated cytotoxic effect induced by zoledronic acid treatment on Human Gingival Fibroblasts

Zoledronic acid (ZA) belongs to bisphosphonates (BPs), drugs administered to treat resorptive bone diseases. Although ZA is largely used in the clinical practice, significant adverse effects of ZA, such as osteonecrosis of the jaw (ONJ), were recorded. The aim of this work was to evaluate the role of Nitric Oxide (NO) in the in vitro response of Human Gingival Fibroblasts (HGFs) to 1, 5, 10 and 100μM ZA. HGFs morphology was evaluated through phase contrast microscopy and live/ dead staining; MTT and ELISA assays were applied to measure cell viability, Collagen Type I and IL6 secretion. ROS production and mitochondrial membrane potential were evaluated by flow cytometry; NO production and NOS activity by spectrophotometric analysis; eNOS and nNOS expression by fluorescence microscopy. Viable fibroblasts are evidenced in control sample while floating dead cells and cells close to detachment phase in ZA treated sample along with decreased level of Collagen Type I. Control sample shows higher number of viable cells respect to ZA treated one and ROS production increases when ZA is added. Released NO in ZA treated sample appears higher and NO overproduction is related to increased nNOS activity. IL 6 secretion level is higher in ZA treated sample than in control one. Our results suggest ROS involvement in NO overproduction, due to nNOS recruitment, both at low and high doses. In turn, NO release seems to be able to trigger the inflammatory response only when high doses are administered

Hydrophobin: fluorosurfactant-like properties without fluorine

The stabilization of fluorous oil droplets in aqueous environment is a critical issue in the preparation of emulsified systems for biomedical applications and in emulsion polymerization technology, due to the extreme immiscibility of aqueous and fluorous phases. We present here a detailed study on the behavior of the hydrophobin HFBI, i.e. a small natural protein endowed with exceptional surface activity, at the interface between aqueous and fluorous phases. HFBI behaves as an efficient and sustainable surfactant at remarkably low concentrations and forms a strong and elastic film at the interface between the two phases. We also show proof-of-concept experiments on the use of HFBI as a surfactant in fluorous oil/water emulsified systems and in microfluidic circuits. This journal is © The Royal Society of Chemistry 2013

Genetic correlations between temperature-induced plasticity of life-history traits in a soil arthropod.

Temperature is considered one of the most important mediators of phenotypic plasticity in ectotherms. However, the costs and benefits shaping the evolution of different thermal responses are poorly elucidated. One of the possible constraints to phenotypic plasticity is its intrinsic genetic cost, such as genetic linkage or pleiotropy. Genetic coupling of the thermal response curves for different life history traits may significantly affect the evolution of thermal sensitivity in thermally fluctuating environments. We used the collembolan Orchesella cincta to study if there is genetic variation in temperature-induced phenotypic plasticity in life history traits, and if the degree of temperature-induced plasticity is correlated across traits. Egg development rate, juvenile growth rate and egg size of 19 inbred isofemale lines were measured at two temperatures. Our results show that temperature was a highly significant factor for all three traits. Egg development rate and juvenile growth rate increased with increasing temperature, while egg size decreased. Line by temperature interaction was significant for all traits tested; indicating that genetic variation for temperature-induced plasticity existed. The degree of plasticity was significantly positively correlated between egg development rate and growth rate, but plasticity in egg size was not correlated to the other two plasticity traits. The findings suggest that the thermal plasticities of egg development rate and growth rate are partly under the control of the same genes or genetic regions. Hence, evolution of the thermal plasticity of traits cannot be understood in isolation of the response of other traits. If traits have similar and additive effects on fitness, genetic coupling between these traits may well facilitate the evolution of optimal phenotypes. However, for this we need to know the selective forces under field conditions. © 2010 Springer Science+Business Media B.V

Alternative delivery of male accessory gland products

To increase fertilization success, males transfer accessory gland products (Acps). Several species have evolved unconventional Acps transfer modes, meaning that Acps are transferred separately from the sperm. By surveying the sperm-free Acps transfer cases, we show that these animals have evolved a common strategy to deliver Acps: they all inject Acps directly through the partner’s body wall into the hemolymph. Our review of this mode of Acps transfer reveals another striking similarity: they all transfer sperm in packages or via the skin, which may leave little room for Acps transfer via the conventional route in seminal fluid. We synthesise the knowledge about the function, and the effects in the recipients, of the Acps found in the widely diverse taxa (including earthworms, sea slugs, terrestrial snails, scorpions and salamanders) that inject these substances. Despite the clearly independent evolution of the injection devices, these animals have evolved a common alternative strategy to get their partners to accept and/or use their sperm. Most importantly, the evolution of the injection devices for the delivery of Acps highlights how the latter are pivotal for male reproductive success and, hence, strongly influence sexual selection