Accelerated biodegradation of FeMn porous alloy coated with ZnO : Effect on cytocompatibility and antibiofilm properties

Altres ajuts: acords transformatius de la UABFe-based alloys are being studied as potential candidates for biodegradable implants; however, their degradation rates remain too slow. To accelerate biodegradation while simultaneously hindering biofilm formation, a ZnO coating was deposited onto porous equiatomic FeMn alloy discs by sol-gel method using dip coating. The effect of the ZnO coating on the microstructure, biodegradability, cytocompatibility, and antibacterial properties were investigated. Biodegradability experiments were performed by immersing the specimens in Hank's balanced salt solution and measuring ion release after up to 28 days of immersion. The experiments showed an increased degradation of the FeMn/ZnO sample due to Fe segregation towards the grain boundaries, formation of iron-manganese oxide, and limited formation of degradation products on ZnO. Further, indirect Saos-2 cell cytotoxicity testing in 24 h sample-conditioned media showed no significant cytotoxicity in concentrations equal to or below 50 %. In addition, the total biofilm biovolume formed by Staphylococcus aureus on the FeMn/ZnO surface was significantly reduced compared to the uncoated FeMn. Taken together, these results show that the ZnO coating on FeMn improves the degradation rate, maintains cytocompatibility, and reduces biofilm accumulation when compared to an uncoated FeMn alloy

Modifications of the duration cof omputer activities at pupils, established by chronometrage

Catedra Igiena Generală, USMF „Nicolae Testemiţanu”, CNSP, CSP Chişinău, CSP EdineţInvestigations were organized into three groups of study. It was measured the duration of the computer' activity at 20 pupils for 6 lessons per day, for five days a week and four trimesters. Chronometrage of the pupils’ activity on the lessons of informatics has shown that the duration of the main operation time is longer than the time spent on distractions. Values of duration of main activities at pupils in this group are situated between the values marked in pupils involved at the lessons of light and heavy objects, approaching the values of those pupils who were engaged by subjects with a high degree of complexity. Cercetările au fost organizate în trei loturi de studiu. Au fost cronometrate activităţile a 20 elevi, pe parcursul a 6 lecţii în zi, 5 zile în săptămână şi 4 trimestre, astfel realizându-se câte 2400 măsurări în fiecare lot cercetat. Cronometrajul activităţilor elevilor la obiectul de informatică indică o durată a timpului de bază a activităţilor mai mari ca timpul abaterilor. La elevii din acest lot activităţile de bază după durată se plasează între valorile înregistrate la elevii de la disciplinile cu grad de complexitate major şi mic, fiind mai aproape după durată de elevii cercetaţi în timpul diciplinilor cu grad de complexitate major

A novel role for GalNAc-T2 dependent glycosylation in energy homeostasis

OBJECTIVE: GALNT2, encoding polypeptide N-acetylgalactosaminyltransferase 2 (GalNAc-T2), was initially discovered as a regulator of high-density lipoprotein metabolism. GalNAc-T2 is known to exert these effects through post-translational modification, i.e., O-linked glycosylation of secreted proteins with established roles in plasma lipid metabolism. It has recently become clear that loss of GALNT2 in rodents, cattle, nonhuman primates, and humans should be regarded as a novel congenital disorder of glycosylation that affects development and body weight. The role of GALNT2 in metabolic abnormalities other than plasma lipids, including insulin sensitivity and energy homeostasis, is poorly understood. METHODS: GWAS data from the UK Biobank was used to study variation in the GALNT2 locus beyond changes in high-density lipoprotein metabolism. Experimental data were obtained through studies in Galnt2(−/−) mice and wild-type littermates on both control and high-fat diet. RESULTS: First, we uncovered associations between GALNT2 gene variation, adiposity, and body mass index in humans. In mice, we identify the insulin receptor as a novel substrate of GalNAc-T2 and demonstrate that Galnt2(−/−) mice exhibit decreased adiposity, alterations in insulin signaling and a shift in energy substrate utilization in the inactive phase. CONCLUSIONS: This study identifies a novel role for GALNT2 in energy homeostasis, and our findings suggest that the local effects of GalNAc-T2 are mediated through posttranslational modification of the insulin receptor

Selective Replacement of Cholesterol with Cationic Amphiphilic Drugs Enables the Design of Lipid Nanoparticles with Improved RNA Delivery

The delivery of RNA across biological barriers can be achieved by encapsulation in lipid nanoparticles (LNPs). Cationic amphiphilic drugs (CADs) are pharmacologically diverse compounds with ionizable lipid-like features. In this work, we applied CADs as a fifth component of state-of-the-art LNPs via microfluidic mixing. Improved cytosolic delivery of both siRNA and mRNA was achieved by partly replacing the cholesterol fraction of LNPs with CADs. The LNPs could cross the mucus layer in a mucus-producing air–liquid interface model of human primary bronchial epithelial cells following nebulization. Moreover, CAD-LNPs demonstrated improved epithelial and endothelial targeting following intranasal administration in mice, without a marked pro-inflammatory signature. Importantly, quantification of the CAD-LNP molar composition, as demonstrated for nortriptyline, revealed a gradual leakage of the CAD from the formulation during LNP dialysis. Altogether, these data suggest that the addition of a CAD prior to the rapid mixing process might have an impact on the composition, structure, and performance of LNPs