Assessment of Novel Water-Borne Coatings Obtained from Composite Latex Particles and Reinforced with TiO2 Nanotubes

Novel, environmentally friendly waterborne coatings were obtained from the filmification of nanostructured latex particles reinforced with inorganic nanotubes. The latex used to form the coatings consists of core-shell particles with a shell functionalized with different amounts of acrylic acid (AA). This external polymer layer was doped, in some cases, with TiO₂ nanotubes at three different concentrations: 100, 500 and 1000 ppm. The composite particles were synthesized in two steps by semi-continuous emulsion polymerization at 75°C. A series of films was prepared by employing core-shell particles with different sizes, core cross-linking and shell functionalization. The coatings obtained were characterized by infrared spectroscopy (FTIR), tapping mode atomic force microscopy (TM-AFM), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetrical analysis (TGA). Drying rates and tests were also performed to further evaluate these films. It was observed that the addition of small amounts of TiO₂ nanotubes contributes to improve the application properties, mainly adhesion to metallic substrates and water impermeability. The resistance to thermal degradation was also strongly increased, as showed by the DSC and TGA analyses.     

Structural Determinants of the Selectivity of 3‐Benzyluracil‐1‐acetic Acids toward Human Enzymes Aldose Reductase and AKR1B10

The human enzymes aldose reductase (AR) and AKR1B10 have been thoroughly explored in terms of their roles in diabetes, inflammatory disorders, and cancer. In this study we identified two new lead compounds, 2‐(3‐(4‐chloro‐3‐nitrobenzyl)‐2,4‐dioxo‐3,4‐dihydropyrimidin‐1(2H)‐yl)acetic acid (JF0048, 3 ) and 2‐(2,4‐dioxo‐3‐(2,3,4,5‐tetrabromo‐6‐methoxybenzyl)‐3,4‐dihydropyrimidin‐1(2H)‐yl)acetic acid (JF0049, 4 ), which selectively target these enzymes. Although 3 and 4 share the 3‐benzyluracil‐1‐acetic acid scaffold, they have different substituents in their aryl moieties. Inhibition studies along with thermodynamic and structural characterizations of both enzymes revealed that the chloronitrobenzyl moiety of compound 3 can open the AR specificity pocket but not that of the AKR1B10 cognate. In contrast, the larger atoms at the ortho and/or meta positions of compound 4 prevent the AR specificity pocket from opening due to steric hindrance and provide a tighter fit to the AKR1B10 inhibitor binding pocket, probably enhanced by the displacement of a disordered water molecule trapped in a hydrophobic subpocket, creating an enthalpic signature. Furthermore, this selectivity also occurs in the cell, which enables the development of a more efficient drug design strategy: compound 3 prevents sorbitol accumulation in human retinal ARPE‐19 cells, whereas 4 stops proliferation in human lung cancer NCI‐H460 cells.     

Urban regeneration policies and mental health in a context of economic crisis in Andalusia (Spain)

Literature suggests that urban regeneration policies might contribute towards improving mental health of residents, but to date there is a lack of empirical research on how these policies and downward social mobility can interact and influence health outcomes. The current study aims to explicitly test whether regeneration policies implemented in deprived Andalusian urban places (southern Spain) moderate the use of anxiolytics and/or antidepressants, taking into consideration families’ downward social mobility during the recent period of economic crisis in Spain. We designed a post intervention survey to retrospectively compare the evolution of psychotropic drug consumption in target and comparison areas. We observe a general increase in the use of anxiolytics and/or antidepressants from 2008 to 2015, specifically for people in whose families the economic crisis had the greatest impact (odds ratio?=?2.18; p value?<?0.001). However, better evolution is observed among residents of the target areas compared with residents of similar urban areas where this kind of polices have been not in force (odds ratio?=?0.50; p value?<?0.05). Therefore, urban regeneration policies might act as moderators of the risk of mental health, particularly when people are subject to the loss of individual/family resources in urban vulnerable contexts.

     

High concentration of phosphorus is a distinctive feature of myelin. An X‐Ray elemental microanalysis study using freeze‐fracture scanning electron microscopy of rat sciatic nerve

We have used rat sciatic nerves submitted to freezing and freeze‐fracture to determine the elemental composition of small domains of the peripheral nerve studied at high resolution by scanning electron microscopy. We found that myelin of Schwann cells is unique in its high content in phosphorus (P) that was more than 10 times higher than P measured in any other cells. This high concentration in P makes myelin chemistry suitable of monitoring at the subcellular level using the herein described methodology. Microsc. Res. Tech. 78:537–539, 2015. © 2015 Wiley Periodicals, Inc.     

Improvement of the stoichiometric network analysis for determination of instability conditions of complex nonlinear reaction systems

Stoichiometric network analysis (SNA), a known method for analyzing complex reaction systems including biochemical ones, is improved and applied to a nonlinear process studied far from equilibrium in a continuously fed, well stirred tank reactor (CSTR). A particular attention is focused on the determination of the narrow range of the control parameter values where the main steady state is unstable and where different dynamic states can be simulated numerically. The instability region, the most important feature of nonlinear reaction systems, is calculated as a function of the SNA parameters (current rates and reciprocal concentrations of intermediate species in the steady state) and simplified by retaining only the dominant terms. Since the number of the current rates is usually larger than the number of linearly independent equations to be used for their calculation, it is shown here that the current rates can be replaced with a smaller number of reaction rates at the steady state. These rates are related to the experimental data in a simple manner. The instability condition is also written as a function of dimensionless parameters derived from the SNA. This general approach is applied to a model of the Bray–Liebhafsky (BL) reaction having seven reactions without direct autocatalysis or autoinhibition, studied under CSTR conditions. Since the model has six intermediate species, it would be very difficult to analyze its instability condition by the conventional procedure, where a sixth order characteristic equation would have to be solved. On the other hand, the instability condition, obtained easily by the improved SNA, locates correctly the oscillatory region using numerical integration. Other dynamic states found earlier with a larger model of the BL reaction, such as mixed-mode oscillations, period doubling and chaos, are also obtained within the theoretically predicted oscillatory region. Thus, besides the general advantages of the improved stoichiometric network analysis as a method appropriate for the examination of complex nonlinear reactions, we show that the various mentioned dynamic states can be obtained by a very simple variant of the model of the BL reaction realized under CSTR conditions.     

Gene Therapy in HIV‐Infected Cells to Decrease Viral Impact by Using an Alternative Delivery Method

The ability of dendrimer 2G‐[Si{O(CH₂)₂N(Me)₂⁺(CH₂)₂NMe₃⁺(I^?)₂}]₈ (NN16) to transfect a wide range of cell types, as well as the possible biomedical application in direct or indirect inhibition of HIV replication, was investigated. Cells implicated in HIV infection such as primary peripheral blood mononuclear cells (PBMC) and immortalized suspension cells (lymphocytes), primary macrophages and dendritic cells, and immortalized adherent cells (astrocytes and trophoblasts) were analyzed. Dendrimer toxicity was evaluated by mitochondrial activity, cell membrane rupture, release of lactate dehydrogenase, erythrocyte hemolysis, and the effect on global gene expression profiles using whole‐genome human microarrays. Cellular uptake of genetic material was determined using flow cytometry and confocal microscopy. Transfection efficiency and gene knockdown was investigated using dendrimer‐delivered antisense oligonucleotides and small interfering RNA (siRNA). Very little cytotoxicity was detected in a variety of cells relevant to HIV infection and erythrocytes after NN16 dendrimer treatment. Imaging of cellular uptake showed high transfection efficiency of genetic material in all cells tested. Interestingly, NN16 further enhanced the reduction of HIV protein 24 antigen release by antisense oligonucleotides due to improved transfection efficiency. Finally, the dendrimer complexed with siRNA exhibited therapeutic potential by specifically inhibiting cyclooxygenase‐2 gene expression in HIV‐infected nervous system cells. NN16 dendrimers demonstrated the ability to transfect genetic material into a vast array of cells relevant to HIV pathology, combining high efficacy with low toxicity. These results suggest that NN16 dendrimers have the potential to be used as a versatile non‐viral vector for gene therapy against HIV infection.     

Urban Water Demand for Service and Industrial Use: The Case of Zaragoza

Increased efforts to improve urban water management are focused on demand side policies, seeking to affect the behavior of users so that a “reasonable” use of water resources is reached. In this framework the accurate characterization of water demand play a major role in obtaining sufficient knowledge about this behavioral response to changes in price. In this paper we focus on the water demand of the services and industries connected to the public water network. To this end, we carry out an empirical estimation of urban water demand for service and industrial use in Zaragoza (Spain). The proposed model is a Koyck flow adjustment demand model, and a price specification, which is constructed as a function of the lagged average price, current marginal price and a price perception parameter. We use a dynamic panel data methodology to estimate the water demand function. As far as we are aware, this approach to service and industrial urban water demand is new in the literature. The analysis suggests that although price has a negative relationship with consumption, such an effect is reduced given that the price elasticity is lower than one in absolute value. Another relevant finding is that service and industrial urban users think that they pay a lower price than the actual price they pay.