Cookeeriksson0817

Macrophages are among the first cells to interact with biomaterials and ultimately determine their integrative fate. Biomaterial surface characteristics like roughness and hydrophilicity can activate macrophages to an anti-inflammatory phenotype. Wnt signaling, a key cell proliferation and differentiation pathway, has been associated with dysregulated macrophage activity in disease. However, the role Wnt signaling plays in macrophage activation and response to biomaterials is unknown. The aim of this study was to characterize the regulation of Wnt signaling in macrophages during classical pro- and anti-inflammatory polarization and in their response to smooth, rough, and rough-hydrophilic titanium (Ti) surfaces. Peri-implant Wnt signaling in macrophage-ablated (MaFIA) mice instrumented with intramedullary Ti rods was significantly attenuated compared to untreated controls. Wnt ligand mRNA were upregulated in a surface modification-dependent manner in macrophages isolated from the surface of Ti implanted in C57Bl/6 mice. In vitro, Wnt mRNAs were regulated in primary murine bone-marrow-derived macrophages cultured on Ti in a surface modification-dependent manner. When macrophageal Wnt secretion was inhibited, macrophage sensitivity to both physical and biological stimuli was abrogated. Loss of macrophage-derived Wnts also impaired recruitment of mesenchymal stem cells and T-cells to Ti implants in vivo. Finally, inhibition of integrin signaling decreased surface-dependent upregulation of Wnt genes. These results suggest that Wnt signaling regulates macrophage response to biomaterials and that macrophages are an important source of Wnt ligands during inflammation and healing. Exosomes and extracellular nanovesicles (NV) derived from mesenchymal stem cells (MSC) may be used for the treatment of ischemic stroke owing to their multifaceted therapeutic benefits that include the induction of angiogenesis, anti-apoptosis, and anti-inflammation. However, the most serious drawback of using exosomes and NV for ischemic stroke is the poor targeting on the ischemic lesion of brain after systemic administration, thereby yielding a poor therapeutic outcome. In this study, we show that magnetic NV (MNV) derived from iron oxide nanoparticles (IONP)-harboring MSC can drastically improve the ischemic-lesion targeting and the therapeutic outcome. Because IONP stimulated expressions of therapeutic growth factors in the MSC, MNV contained greater amounts of those therapeutic molecules compared to NV derived from naive MSC. Following the systemic injection of MNV into transient middle-cerebral-artery-occlusion (MCAO)-induced rats, the magnetic navigation increased the MNV localization to the ischemic lesion by 5.1 times. The MNV injection and subsequent magnetic navigation promoted the anti-inflammatory response, angiogenesis, and anti-apoptosis in the ischemic brain lesion, thereby yielding a considerably decreased infarction volume and improved motor function. learn more Overall, the proposed MNV approach may overcome the major drawback of the conventional MSC-exosome therapy or NV therapy for the treatment of ischemic stroke. In this work, biochar based hydrogel microspheres were fabricated successfully to develop pH and ion strength dual-stimuli responsively controlled-release system for hydrophilic pesticide. Herein, gentian violet (GV) was selected as model hydrophilic pesticide. Taking advantage of the cross-linking reaction, GV was incorporated into biochar and the 3D network-structured hydrogel, guaranteeing a satisfying encapsulation efficiency and sustained release of pesticide. The leaching behavior of pesticide in simulated soil column at different pHs and ion strength was in accordance with the corresponding release performance, and bulk of pesticide was retarded on the surface. In addition, the pesticide carrier had nearly no toxic effect on the cell proliferation and zebrafish embryo, displaying a good biosafety. The work provides a promising strategy with a low-cost and simple procedure that could regulate pesticide release behavior, decrease leaching loss, and improve the utilization efficiency of pesticide. Soil nitrogen (N) mineralization is a microbially-mediated biogeochemical process that is strongly influenced by changing climates. However, little information is available on the mechanisms behind the response of N mineralization to prolonged warming coupled with drought in soils covered by biocrusts. We used open top chambers to investigate the rate of soil N transformation (ammonification, nitrification and mineralization), enzyme activity and gene abundance in response to warming coupled with reduced precipitation over three years (2016-2018). Warming and drought significantly reduced the N transformation rate, extracellular enzyme activity, and gene abundance in moss-covered soil. For cyanobacteria-covered soil, however, it inhibited enzyme activity and increased the abundance of the nitrification-related genes and therefore nitrification rate. Our treatments had no obvious effects on N transformation and enzyme activity, but reduced gene abundance in bare soil. Biocrusts may facilitate N transformation while the degradation of moss crust caused by climate warming will dampen any regulating effect of biocrusts on the belowground microbial community. Furthermore, belowground microbial communities can mediate N transformation under ongoing warming and reduced precipitation by suppressing ammonification- and nitrification-related gene families, and by stimulating nitrification-related gene families involved in cyanobacteria-covered soil. This study provides a basis for identifying the functional genes involved in key processes in the N cycle in temperate desert ecosystems, and our results further highlight the importance of different biocrusts organisms in the N cycle in temperate deserts as Earth becomes hotter and drier. V.Humic acids (HA) play an important role in the distribution, toxicity, and bioavailability of metals in the environment. Humic-like acids (HLA) that simulate geochemical processes can be prepared by NaOH aqueous extraction from hydrochars produced by hydrothermal carbonization (HTC). HLA can exhibit properties such as those found in HA from soils, which are known for their ability to interact with inorganic and organic compounds. The molecular characteristics of HLA and HA help to explain the relationship between their molecular features and their interaction with metallic species. The aim of this study is to assess the molecular features of HA extracted from Terra Mulata (TM) and HLA from hydrochars as well as their interaction with metals by using Cu(II) ions as a model. The results from 13C NMR, elemental analysis, FTIR, and UV-Vis showed that HA are composed mostly of aromatic structures and oxygenated functional groups, whereas HLA showed a mutual contribution of aromatic and aliphatic structures as main constituents.