Porous Electrospun Fibers with Self‐Sealing Functionality: An Enabling Strategy for Trapping Biomacromolecules

Stimuli‐responsive porous polymer materials have promising biomedical application due to their ability to trap and release biomacromolecules. In this work, a class of highly porous electrospun fibers is designed using polylactide as the polymer matrix and poly(ethylene oxide) as a porogen. Carbon nanotubes (CNTs) with different concentrations are further impregnated onto the fibers to achieve self‐sealing functionality induced by photothermal conversion upon light irradiation. The fibers with 0.4 mg mL^?1 of CNTs exhibit the optimum encapsulation efficiency of model biomacromolecules such as dextran, bovine serum albumin, and nucleic acids, although their photothermal conversion ability is slightly lower than the fibers with 0.8 mg mL^?1 of CNTs. Interestingly, reversible reopening of the surface pores is accomplished with the degradation of PLA, affording a further possibility for sustained release of biomacromolecules after encapsulation. Effects of CNT loading on fiber morphology, structure, thermal/mechanical properties, degradation, and cell viability are also investigated. This novel class of porous electrospun fibers with self‐sealing capability has great potential to serve as an enabling strategy for trapping/release of biomacromolecules with promising applications in, for example, preventing inflammatory diseases by scavenging cytokines from interstitial body fluids.     

Light-Controlled Growth Factors Release on Tetrapodal ZnO-Incorporated 3D-Printed Hydrogels for Developing Smart Wound Scaffold

Advanced wound scaffolds that integrate active substances to treat chronic wounds have gained significant recent attention. While wound scaffolds and advanced functionalities have previously been incorporated into one medical device, the wirelessly triggered release of active substances has remained the focus of many research endeavors. To combine multiple functions including light-triggered activation, antiseptic, angiogenic, and moisturizing properties, a 3D printed hydrogel patch encapsulating vascular endothelial growth factor (VEGF) decorated with photoactive and antibacterial tetrapodal zinc oxide (t-ZnO) microparticles is developed. To achieve the smart release of VEGF, t-ZnO is modified by chemical treatment and activated through ultraviolet/visible light exposure. This process would also make the surface rough and improve protein adhesion. The elastic modulus and degradation behavior of the composite hydrogels, which must match the wound healing process, are adjusted by changing t-ZnO concentrations. The t-ZnO-laden composite hydrogels can be printed with any desired micropattern to potentially create a modular elution of various growth factors. The VEGF-decorated t-ZnO-laden hydrogel patches show low cytotoxicity and improved angiogenic properties while maintaining antibacterial functions in vitro. In vivo tests show promising results for the printed wound patches, with less immunogenicity and enhanced wound healing.     

Bringing health impact assessment to the Mongolian resource sector: a story of successful diffusion

Following the 2009 signing of the stability agreement between the Mongolian Government and Canadian mining company Turquoise Hill Resources (formerly known as Ivanhoe Mines), researchers from Simon Fraser University secured funding from the Canadian Institutes for Health Research to conduct applied knowledge translation (KT) research that introduces health impact assessment (HIA) to Mongolia's rapidly emerging resource sector. HIA is a highly regarded informed decision-making tool that helps to identify, assess and mitigate (or promote) potential positive and negative human health impacts of policies, projects and programs. We engaged in a series of knowledge synthesis, KT and dissemination activities with key public and private sector stakeholders as well as community representatives. Our goals were to develop consensus on a socially and culturally appropriate approach to equity-focused HIA, draw on this consensus to develop a contextualized HIA toolkit, build local HIA capacity based on this toolkit, strengthen the HIA regulatory environment and provide evidence-based support for efforts to institutionalize HIA in the resource sector. These efforts have resulted in the inclusion of HIA in the environmental impact assessment law of Mongolia, and the focus has now shifted from KT to further supporting HIA institutionalization and practice.