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There is currently a constant search for ecofriendly bioproducts, which could contribute to various biomedical applications. Among bioproducts, exopolysaccharides are prominent contemporary extracellular biopolymers that are produced by a great variety of bacterial species. These homo- or heteropolymers are composed of monomeric sugar units linked by glycosidic bonds, which are secreted to the external medium. Bacillus spp. are reported to be present in different ecosystems and produce exopolysaccharides with different biological properties such as antioxidant, antibacterial, antiviral anti-inflammatory, among others. Since a great diversity of bacterial strains are able to produce exopolysaccharides, a great variation in the molecular composition is observed, which is indeed present in some of the chemical structures predicted until date. These molecular characteristics and their relations with different biological functions are discussed in order to visualize future applications in biomedical section.

The Andean tree Schinus areira L. has multiple traditional uses, from the treatment of bronchitis and rheumatic diseases to menstrual cycle regulation and wound healing. With reported hypotensive, analgesic, antitumoral and anti-inflammatory properties, it acts predominantly against diseases related to oxidative stress. This study focuses on the antioxidant activity and phytochemical profile of the extracts of Schinus areira L. Serial extraction of the fruits was performed both by maceration and by Soxhlet. Total phenols and flavonoids were measured using the Folin-Ciocalteu method and AlCl3, respectively. In vitro antioxidant activity was determined by FRAP and DPPH. Results were similar for both extraction methods. Primary metabolites detected included carbohydrates, proteins and amino acids; secondary metabolites included tannins, flavonoids, saponins, steroids and triterpenes. Antioxidant activity was confirmed for ethyl acetate, methanolic and aqueous extracts. The methanolic extract had both the highest polyphenol content (>195 mg GAE/ g dry weight) and the highest antioxidant activity [EC50 > 476 μg/mL; > 273 mg AA/g dry weight (DPPH); > 301 mg AA/ g dry weight (FRAP)]. The extract does not produce macrophage cytotoxicity in RAW 264.7, which is indicated by an average cytotoxicity of 2% over 24 h. Our study serves as a starting point for future research on the pharmacological properties of Schinus areira L.

Non-cell-autonomous mechanisms contribute to neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), in which astrocytes release unidentified factors that are toxic to motoneurons (MNs). We report here that mouse and patient iPSC-derived astrocytes with diverse ALS/FTD-linked mutations (SOD1, TARDBP, and C9ORF72) display elevated levels of intracellular inorganic polyphosphate (polyP), a ubiquitous, negatively charged biopolymer. PolyP levels are also increased in astrocyte-conditioned media (ACM) from ALS/FTD astrocytes. ACM-mediated MN death is prevented by degrading or neutralizing polyP in ALS/FTD astrocytes or ACM. Studies further reveal that postmortem familial and sporadic ALS spinal cord sections display enriched polyP staining signals and that ALS cerebrospinal fluid (CSF) exhibits increased polyP concentrations. Our in vitro results establish excessive astrocyte-derived polyP as a critical factor in non-cell-autonomous MN degeneration and a potential therapeutic target for ALS/FTD. The CSF data indicate that polyP might serve as a new biomarker for ALS/FTD.

Electrodeionization (EDI) is an advantageous technology for desalination of waters with the range of salinity found in brackish water. Although modeling can help to understand the behavior of EDI cells, no reliable models connecting relevant operational variables have been published so far. Thus, this paper presents the experimental study and the mathematical modeling of an electrodeionization process used for the desalination of brackish water. The desalination process was carried out in a 4-compartment laboratory EDI cell. The model developed proposes an approach to the transport of ions in the liquid flowing in the mixed-bed resin's interstitial space. This transport is driven by the potential gradient in the liquid phase, formed by the different electric potential of cation- and anion-exchange resin particles and the Donnan potential at the interface. The model is used to analyze the current density distribution in the EDI cell and its effect on ion removal and performance to identify ineffective regions of the cell. The comparison of model calculation with experimental data shows the model to be capable of describing the effect of concentration (0.01 and 0.02 M) and cell voltage (7, 10.5 and 14 V) changes on current density and desalination rate.

The development of safe and effective liberation mechanisms is the most important requirements for the clinical implementation of drug-delivery vectors. Among non-viral delivery systems, the most popular ones are members of the groups of cationic lipids and polymers. Both subgroups are able to transport nucleic acids, protect them against environmental influences and deliver them to the cells. Without a doubt, these systems bear certain disadvantages as well, among these, high toxicities for in vitro/in vivo applications in the case of liposomes and an almost infinite inherent structural complexity for polymers. From this point of view, an ideal transfection system would combine the characteristic advantages of cationic lipids and polymers, while at the same time minimizing their limitations. Recently, a hybrid structure consisting of a lipid and a spherical polymer (dendrimer) was reported, which was consequently named amphiphilic dendrimer (AD). Gratifyingly, these molecules have shown both excellent delivery properties and payload-liberation as well as low toxicity, mainly due to their chimeric structure, bearing a hydrophobic alkylic chain and a hydrophilic dendron as head group.To gain insight into these nanoparticles we studied them using a molecular simulation approach. Specifically, we studied the structural properties that govern the self-assembly organization and how these complexes interact with DNA. Since the computational cost for this kind of studies at atomic level are very high, a coarse-grained approach was used. All the calculations were performed using Martini force-field. Using this approach, a large number of dendrimeric systems were studied using large-scale molecular simulation, which allow us to explore a large number of configurational and conformational states of the self-assembly process, obtaining significant statistical results.