Crosstalk among Calcium ATPases: PMCA,SERCA and SPCA in Mental Diseases

Calcium in mammalian neurons is essential for developmental processes, neurotransmitter release, apoptosis, and signal transduction. Incorrectly processed Ca²⁺ signal is well-known to trigger a cascade of events leading to altered response to variety of stimuli and persistent accumulation of pathological changes at the molecular level. To counterbalance potentially detrimental consequences of Ca²⁺, neurons are equipped with sophisticated mechanisms that function to keep its concentration in a tightly regulated range. Calcium pumps belonging to the P-type family of ATPases: plasma membrane Ca²⁺-ATPase (PMCA), sarco/endoplasmic Ca²⁺-ATPase (SERCA) and secretory pathway Ca²⁺-ATPase (SPCA) are considered efficient line of defense against abnormal Ca²⁺ rises. However, their role is not limited only to Ca²⁺ transport, as they present tissue-specific functionality and unique sensitive to the regulation by the main calcium signal decoding protein—calmodulin (CaM). Based on the available literature, in this review we analyze the contribution of these three types of Ca²⁺-ATPases to neuropathology, with a special emphasis on mental diseases.     

Influence of the addition of multi-walled carbon nanotubes on the thermal and mechanical properties of polyamide-11 before and after aging tests

In this work, the preparation and characterization of nanocomposites of commercial polyamide-11 reinforced with multi-walled carbon nanotubes (MWCNT), untreated, oxidized or with the modified surface through silanization with 3-aminopropyl trimethoxy silane (APTMS), in concentrations of 0.1%, 0.5%, and 1.0 wt% in the polymer matrix was investigated. The processing of the nanocomposites was carried out via mixing in the molten state in a twin-screw mini-extruder at 200°C under 60 rpm screw rotation speed, with a residence time of 7 min. The addition of the MWCNT increased the thermal stability of PA11, predominantly with 0.5% of silanized nanotubes, as observed by the thermogravimetric analysis. X-ray diffraction and differential scanning calorimetry analyses indicated that the degree of crystallinity of the formulations increased with the nanofiller content. On the other hand, the use of the highest concentration generated agglomerates, suggesting less dispersion in the matrix and, consequently, a reduction in crystallinity. Dynamic mechanical thermal analysis showed that the silanization process promoted an increase in both loss and storage moduli. All produced nanocomposites obtained values of corrected inherent viscosity above 1.20 dl/g, before and after the aging test. The use of lower load levels promoted better processability due to the lubricating effect of the nanotubes and an increase in the hydrophobic character of the samples, as observed by the increase of the contact angle.     

Consumption of Fish in Chronic Kidney Disease – A Matter of Depth

Fish is an excellent source of ω-3 polyunsaturated fatty acids (PUFAs), amino acids, collagen, vitamins, and iodine and its intake is associated with health benefits, mainly reduces risk of cardiovascular mortality. However, recent studies have shown that fish is also an important source of trimethylamine N-oxide (TMAO), a uremic toxin produced by the gut microbiota that promotes an increased risk of cardiovascular diseases. In patients with chronic kidney disease (CKD), TMAO levels are markedly increased due to gut dysbiosis and reduced kidney function. No study has yet evaluated the effects of a fish-rich diet on TMAO plasma levels and cardiovascular outcomes. This review discusses the pros and cons of a fish-rich diet in patients with CKD – a matter of depth.     

Ductile/brittle PA6/PS system: Effect of carbon nanoplatelets-modified interface on performance

Addition of rigid PS to ductile PA6 can lead to higher toughness provided plastic deformation of PS is achieved. The current study deals with upgrading of this system by graphene, graphene oxide (GO), and GO with grafted polystyrene (GO-g-PS). Low amount of these carbon nanoplatelets can enhance performance of the PA/PS 90/10 system with the best-balanced properties achieved with GO-g-PS by unique combination of reinforcement with the favorable effect of the GO-g-PS-modified interface on plastic deformation of the PS phase causing higher impact resistance. Simultaneous linking of PA chains and hydrogen bonding causes “anchoring” of PS inclusions in the PA6 phase. This results in support of hydrostatic pressure evolution during loading and thus extensive yielding of PS. Another positive effect is reduction of pullout of in situ formed fibrous inclusions, which is different from rigid short-fiber composites. The study highlights high potential of GO modified with polymer chains to upgrade polymer systems via tailoring the interface.     

Protein‐loaded sodium alginate and carboxymethyl cellulose beads for controlled release under simulated gastrointestinal conditions

Network characteristics of sodium alginate and carboxymethyl cellulose, in relation to the controlled release of bovine serum albumin under simulated gastrointestinal conditions, have been examined. Small‐deformation dynamic oscillation in‐shear, compression testing and optical microscopy were employed to monitor the structural characteristics of polysaccharide beads as excipients for protein entrapment. Work focused on gastrointestinal functionality and controlled release utilising variable acidity and counterion addition in preparations. Beads were found to shrink in gastric and swell in intestinal conditions, thus emphasising the disparate effect of experimental conditions. Changes in mechanical properties reflected alterations in gel microstructure, with beads becoming relatively strong in the gastric environment. In contrast, networks were weakened in the intestinal environment resulting in bead disintegration towards the end of digestion time. This type of structural behaviour allows the controlled delivery of the protein, as a model bioactive, in a particular part of the gastrointestinal tract.     

Exposure to Iron Oxide Nanoparticles Coated with Phospholipid-Based Polymeric Micelles Induces Biochemical and Histopathological Pulmonary Changes in Mice

The biochemical and histopathological changes induced by the exposure to iron oxide nanoparticles coated with phospholipid-based polymeric micelles (IONPs-PM) in CD-1 mice lungs were analyzed. After 2, 3, 7 and 14 days following the intravenous injection of IONPs-PM (5 and 15 mg Fe/kg bw), lactate dehydrogenase (LDH) activity, oxidative stress parameters and the expression of Bax, Bcl-2, caspase-3 and TNF-α were evaluated in lung tissue. An increase of catalase (CAT) and glutathione reductase (GR) activities on the second day followed by a decrease on the seventh day, as well as a decline of lactate dehydrogenase (LDH), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity on the third and seventh day were observed in treated groups vs. controls. However, all these enzymatic activities almost fully recovered on the 14th day. The reduced glutathione (GSH) and protein thiols levels decreased significantly in nanoparticles-treated groups and remained diminished during the entire experimental period; by contrast malondialdehyde (MDA) and protein carbonyls increased between the 3rd and 14th day of treatment vs. control. Relevant histopathological modifications were highlighted using Hematoxylin and Eosin (H&E) staining. In addition, major changes in the expression of apoptosis markers were observed in the first week, more pronounced for the higher dose. The injected IONPs-PM generated a dose-dependent decrease of the mouse lung capacity, which counteracted oxidative stress, thus creating circumstances for morphopathological lesions and oxidation processes.