Coupling a Chlor-Alkali Membrane Electrolyzer Cell to a Wind Energy Source: Dynamic Modeling and Simulations

Renewable energy sources are becoming a greater component of the electrical mix, while being significantly more volatile than conventional energy sources. As a result, net stability and availability pose significant challenges. Energy-intensive processes, such as chlor-alkali electrolysis, can potentially adjust their consumption to the available power, which is known as demand side management or demand response. In this study, a dynamic model of a chlor-alkali membrane cell is developed to assess the flexible potential of the membrane cell. Several improvements to previously published models were made, making the model more representative of state-of-the-art CA plants. By coupling the model with a wind power profile, the current and potential level over the course of a day was simulated. The simulation results show that the required ramp rates are within the regular operating possibilities of the plant for most of the time and that the electrolyte concentrations in the cell can be kept at the right level by varying inlet flows and concentrations. This means that a CA plant can indeed be flexibly operated in the future energy system.

PCSK9 as a Target for Development of a New Generation of Hypolipidemic Drugs

PCSK9 has now become an important target to create new classes of lipid-lowering drugs. The prevention of its interaction with LDL receptors allows an increase in the number of these receptors on the surface of the cell membrane of hepatocytes, which leads to an increase in the uptake of cholesterol-rich atherogenic LDL from the bloodstream. The PCSK9 antagonists described in this review belong to different classes of compounds, may have a low molecular weight or belong to macromolecular structures, and also demonstrate different mechanisms of action. The mechanisms of action include preventing the effective binding of PCSK9 to LDLR, stimulating the degradation of PCSK9, and even blocking its transcription or transport to the plasma membrane/cell surface. Although several types of antihyperlipidemic drugs have been introduced on the market and are actively used in clinical practice, they are not without disadvantages, such as well-known side effects (statins) or high costs (monoclonal antibodies). Thus, there is still a need for effective cholesterol-lowering drugs with minimal side effects, preferably orally bioavailable. Low-molecular-weight PCSK9 inhibitors could be a worthy alternative for this purpose.

Nascent Adhesion Clustering: Integrin-Integrin and Integrin-Substrate Interactions

Nascent adhesions (NAs) are a general precursor to the formation of focal adhesions (FAs) that provide a fundamental mechanism for cell adhesion that is, in turn, involved in cell proliferation, migration, and mechanotransduction. Nascent adhesions form when cells come into contact with substrates at all rigidities and generally involve the clustering of ligated integrins that may recruit un-ligated integrins. Nascent adhesions tend to take on characteristic sizes in the range of O(100nm–150nm) in diameter and tend to contain integrin numbers of O(20–60). The flexible, adaptable model we present provides and clear explanation of how these conserved cluster features come about. Our model is based on the interaction among ligated and un-ligated integrins that arise due to deformations that are induced in the cell membrane-cell glycocalyx and substrate system due to integrin activation and ligation. This model produces a clearly based interaction potential, and from it an explicit interaction force among integrins, that our stochastic diffusion-interaction simulations then show will produce nascent clusters with experimentally observed characteristics. Our simulations reveal effects of various key parameters related to integrin activation and ligation as well as some unexpected and previously unappreciated effects of parameters including integrin mobility and substrate rigidity. Moreover, the model’s structure is such that refinements are readily incorporated and specific suggestions are made as to what is required for further progress in understanding nascent clustering and the development of mature focal adhesions in a truly predictive manner.

GM3 Ganglioside Linked to Neurofibrillary Pathology in a Transgenic Rat Model for Tauopathy

Glycosphingolipids (GSLs) are amphipathic lipids composed of a sphingoid base and a fatty acyl attached to a saccharide moiety. GSLs play an important role in signal transduction, directing proteins within the membrane, cell recognition, and modulation of cell adhesion. Gangliosides and sulfatides belong to a group of acidic GSLs, and numerous studies report their involvement in neurodevelopment, aging, and neurodegeneration. In this study, we used an approach based on hydrophilic interaction liquid chromatography (HILIC) coupled to high-resolution tandem mass spectrometry (HRMS/MS) to characterize the glycosphingolipid profile in rat brain tissue. Then, we screened characterized lipids aiming to identify changes in glycosphingolipid profiles in the normal aging process and tau pathology. Thorough screening of acidic glycosphingolipids in rat brain tissue revealed 117 ganglioside and 36 sulfatide species. Moreover, we found two ganglioside subclasses that were not previously characterized—GT1b-Ac2 and GQ1b-Ac2. The semi-targeted screening revealed significant changes in the levels of sulfatides and GM1a gangliosides during the aging process. In the transgenic SHR24 rat model for tauopathies, we found elevated levels of GM3 gangliosides which may indicate a higher rate of apoptotic processes.

Genome-wide Identification and Transcriptional Profiling of New Cobra-like Genes in Bread Wheat (Triticum Aestivum)

Background: The COBL gene encodes a plant-specific glycosylphosphatidylinositol (GPI)-anchored protein. Recently identified COBRA genes supposed as a key regulator of the orientation of cell expansion in the root indicating that Cobra gene family members are likely to be important new players at the plasma membrane-cell wall interface. Methods and Results: By performing a database search and domain prediction, we identified five genes named as TaCOBL 1, TaCOBL 2, TaCOBL 3, TaCOBL 4 and TaCOBL 5, and selected for further analysis. Chromosomal locations of each gene were drawn on karyotype. Structure of genes, promoter analysis and phylogenetic analysis were done using bioinformatics tools and databases. Set of novel SNPs were also predicted. Gene ontologies were analyzed, and pathways involving cobra genes were predicted. Whole genes of 3kb to 4kb were successfully amplified. Five set of primers were designed targeting TaCOBL 1, TaCOBL 2, TaCOBL 3 TaCOBL 4 and TaCOBL 5 genes. Expression of COBL genes were checked in root and shoot by using qPCR. The qRT-PCR revealed that expression TaCOBL genes can be regulated under abiotic stress such drought stress. Conclusion: The comprehensive annotation and expression profiling of COBL genes performed in this study enhanced our understanding and these genes were found to play a significant role in drought stress. Our findings lay the groundwork for further functional investigation of COBL genes mechanism.

A synergy interaction of artocarpin and tetracycline against Pseudomonas aeruginosa and its mechanism of action on membrane permeability

The emergence of antibacterial resistance has significantly increased. Pseudomonas aeruginosa is associated with nosocomial infection and difficult to control. Artocarpin, a flavonoid from Artocarpus heterophyllus Lam. exhibits several pharmacological properties including antibacterial. The study was performed to evaluate interaction between artocarpin and antibiotics including tetracycline against P. aeruginosa. Its mechanism of action on membrane permeability was also investigated. Broth microdilution was conducted for the susceptibility assay. The interaction of artocarpin and antibiotics was evaluated using checkerboard method, the effect on alteration of membrane cell was investigated using bacteriolysis and the released of 260 nm materials. Artocarpin showed moderate to weak activity against the Gram-negative bacteria including P. aeruginosa with MIC values in the range of 31.25–250 μg/mL. A synergistic effect against P. aeruginosa was produced by the combination of artocarpin (31.25 μg/mL) and tetracycline (1.95 μg/mL) with FICI of 0.37. The time-killing assay showed that artocarpin enhance the antibacterial activity of tetracycline against P. aeruginosa by completely inhibiting the bacterial growth. Additionally, the mixture of artocarpin (31.25 μg/mL) and tetracycline (1.95 μg/mL) disrupted membrane permeability and lead to cell death. These results proposed that the combination of artocarpin and tetracycline may be used to overcome P. aeruginosa infection.

Factors Influencing the Formation of Sodium Hydroxide by an Ion Exchange Membrane Cell

The present study aimed to evaluate the factors that influence the formation of sodium hydroxide (NaOH) by means of an electrolytic cell with ion exchange membranes. To achieve this experiment, the NaOH production cell had to be designed and built inexpensively, using graphite electrodes. The operational parameters in our study were: initial NaOH concentration, applied voltage, and temperature. All experiments were carried out using model NaCl solutions with a concentration of 40 g/L for 150 min. The results of the experiment were that the NaOH concentration, conductivity, and pH presented an increasing linear trend with the electrolysis time. Finally, it was possible to obtain the efficiency level of the electric current in our investigation, which was an average of 80.2%, that indicated good performance of the built cell.