Pt(IV) Prodrugs with NSAIDs as Axial Ligands

A chemo-anti-inflammatory strategy is of interest for the treatment of aggressive cancers. The platinum (IV) prodrug with non-steroidal anti-inflammatory drugs (NSAIDs) as axial ligands is designed to efficiently enter tumor cells due to high lipophilicity and release the cytotoxic metabolite and NSAID intracellularly, thereby reducing side effects and increasing the therapeutic efficacy of platinum chemotherapy. Over the last 7 years, a number of publications have been devoted to the design of such Pt(IV) prodrugs in combination with anti-inflammatory chemotherapy, with high therapeutic efficacy in vitro and In vivo. In this review, we summarize the studies devoted to the development of Pt(IV) prodrugs with NSAIDs as axial ligands, the study of the mechanism of their cytotoxic action and anti-inflammatory activity, the structure–activity ratio, and therapeutic efficacy.     

Dielectric and tunability properties of La-doped BaTiO3 ceramics

La-doped BaTiO₃ (x = 0.001; 0.0025; 0.005; 0.01; 0.025) ceramics were prepared via conventional solid state reaction and sintered at 1300 °C for 6 h, resulting in dense single phase ceramics with homogeneous microstructures. The temperature dependence of dielectric permittivity of the ceramics has been investigated. The results show a decrease of T_C with lanthanum addition. The degree of diffuseness of phase transition is more pronounced for high La content, implying the existence of a composition-induced phase transition of the ceramics. The dc-tunability at room temperature was investigated and experimental data were discussed in terms of the Johnson model completed with a Langevin term that describes “extrinsic” contribution to the non-linear ?(E) dependences.     

Aligned Growth of Semiconductor Nanowires on Scratched Amorphous Substrates

Aligned growth of planar semiconductor nanowires (NWs) on crystalline substrates has been widely demonstrated during the past two decades and was used for the fabrication of a large variety of devices. However, the dependence on single-crystal substrates is a major obstacle in the way of implementing NW-based applications in today's silicon- and glass-based technologies. Here, the guided growth of semiconductor NWs is demonstrated along nanoscale-depth scratches, created in a nonlithographic process on amorphous oxidized silicon wafers and soda-lime glass. Scratches are created on the substrates in a few seconds using a robust and scalable mechanical polishing process. Growth of planar NWs of different materials (CdS, CdSe, ZnSe, and ZnO) guided by scratches on Si/SiO₂ wafers and glass is demonstrated and studied. Photoluminescence measurements from individual NWs grown along scratches show that the interaction with the substrate preserves the optical properties of the material. Crystallographic analysis indicates that all materials grow as single crystals, and the influence of the scratches on the different materials is discussed in terms of morphology, crystallinity, and crystallographic orientations. This process opens the way to large-scale integration of NWs into functional devices by guided growth for various applications including displays, polarized light sensors, and smart windows.     

Comparison of the performance and durability of PEM fuel cells with different Pt-activated microporous layers

We report on a comparative study of the performance level of H₂/O₂ PEM fuel cells in which the catalytic layers containing Pt nanoparticles were deposited on the microporous layer side of gas diffusion electrodes, using three different deposition techniques: (i) by magnetron sputtering, (ii) by impregnation followed by chemical reduction (using either ethylene glycol or hydrogen or sodium borohydride as reducing agent), and (iii) by spraying a catalytic ink (containing either Pt/C or bulk Pt particles). The microstructure and chemical composition of the different catalytic layers has been determined by SEM, TEM, XRD and XPS analysis. Their electrochemical surface areas have been determined by cyclic voltammetry. The i-V curves have been measured and compared. A durability stress test based on cycles of potential was used to assess the degradation rate of the different catalytic layers and to rank performance.     

Effects of Alzheimer-Like Pathology on Homocysteine and Homocysteic Acid Levels—An Exploratory In Vivo Kinetic Study

Hyperhomocysteinemia has been suggested potentially to contribute to a variety of pathologies, such as Alzheimer’s disease (AD). While the impact of hyperhomocysteinemia on AD has been investigated extensively, there are scarce data on the effect of AD on hyperhomocysteinemia. The aim of this in vivo study was to investigate the kinetics of homocysteine (HCys) and homocysteic acid (HCA) and effects of AD-like pathology on the endogenous levels. The mice received a B-vitamin deficient diet for eight weeks, followed by the return to a balanced control diet for another eight weeks. Serum, urine, and brain tissues of App^NL-G-F knock-in and C57BL/6J wild type mice were analyzed for HCys and HCA using LC-MS/MS methods. Hyperhomocysteinemic levels were found in wild type and knock-in mice due to the consumption of the deficient diet for eight weeks, followed by a rapid normalization of the levels after the return to control chow. Hyperhomocysteinemic App^NL-G-F mice had significantly higher HCys in all matrices, but not HCA, compared to wild type control. Higher serum concentrations were associated with elevated levels in both the brain and in urine. Our findings confirm a significant impact of AD-like pathology on hyperhomocysteinemia in the App^NL-G-F mouse model. The immediate normalization of HCys and HCA after the supply of B-vitamins strengthens the idea of a B-vitamin intervention as a potentially preventive treatment option for HCys-related disorders such as AD.     

Testing adaptation policies for software components

Self-adaptive systems have to implement adaptation policies described by sets of rules that express how the components are reconfigured within the system, the priority of a given reconfiguration to happen, when a given (sequence of) event(s) occurs, and when specific conditions on the system state are satisfied. However, when this priority is given by a fuzzy value (e.g., high, medium, low) depending on external and internal events, it has to be implemented inside the software with particular implementation choices made. This paper is dedicated to the validation of adaptation policies, using a model-based testing approach and a verdict establishment that is based on both the runtime verification of temporal properties, and the detection of inconsistencies between the adaptation policy and the reconfigurations implemented in the self-adaptive system. We propose means to establish a test verdict based on the respect of the adaptation policy by the implementation, along with coverage measures of the rules. This provides interesting feedback on the adaptation policy rules, allowing to detect reconfigurations that should not have occurred, high-priority reconfigurations that are never triggered, or low-priority reconfigurations that are too frequently executed, potential inconsistencies in the rules, or wrong interpretation of priorities. The test verdict is made based on the analysis of the execution traces of the system, which is stimulated using a usage model that describes the probabilities of external events to occur. An experiment, performed on a vehicular ad-hoc network of autonomous vehicles, illustrates the interest of the approach.

     

Organic acid catalyzed synthesis of 5-methylresorcinol based organic aerogels in acetonitrile

A method of preparing 5-methylresorcinol and formaldehyde based organic aerogels in non-aqueous media with a benzoic acid derivative as a catalyst is being proposed in this paper. Here acetonitrile is used as a solvent that allows direct drying with carbon dioxide over the supercritical state without the need for a solvent exchange. The acidic properties of 2,6-dihydroxy-4-methyl benzoic acid promote the reaction of sol–gel polymerization, and at the same time it takes part in the reaction as a co-monomer and influences the nanostructure of the material. The evolution of the polymer was monitored using nuclear magnetic resonance spectroscopy and the structure of the resulting organic aerogels depending on the molar ratio of 5-methylresorcinol to 2,6-dihydroxy-4-methyl benzoic acid was studied by nitrogen adsorption–desorption measurements, scanning electron microscopy and infrared spectrometry.     

Articular cartilage: New directions and barriers of scaffolds development – review

Despite progress which has been made in recent years in the field of cell-based therapies or cell scaffolds for cartilage regeneration, a lot of work still needs to be done. Scaffolds remain a great base for tissue regeneration. However, proper implantation procedures or post-treatment still await development.

In this review we summarize paths of cartilage treatment, especially focusing on cell scaffold design and manufacture. As well as the advantages and disadvantages of available or investigated methods and materials, especially focusing on cartilage scaffold design. We show the most promising directions and barriers in the creation of healthy tissue.     

Main parameters influencing the design of photocatalytic reactors for wastewater treatment: a mini review

The research in the heterogeneous photocatalysis to remove different types of pollutants in liquid phase has notably increased in the last years. The main objectives of the research dealing with photocatalysis were: (i) to shift the photoactivity of catalysts in the visible light range or to increase the degradation rate; (ii) the use of the artificial light sources (low pressure lamp, high pressure lamp, LEDs, and optical fibers) and solar light; (iii) photocatalysts recovering and deactivation; (iv) photoreactor configuration; (v) photodegradation of contaminants of emerging concern; and (vi) verification of induced effects from the photocatalytic treatment, such as the induction of bacterial resistance. Here, one of the main problems in the practical application of photocatalysis, which is the photoreactors scale-up, is addressed with the use of mathematical modeling. In this perspective, this mini review reports a literature exam of the main parameters that are important to take into account for the design and the development of photoreactors for wastewater treatment, and through the use of computational fluid dynamics models (CFD). © 2020 Society of Chemical Industry