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Sulfur mustard (SM) is a blister‐producing chemical warfare agent which could lead to a cascade of systemic damage, especially severe acute lung injury. Oxidative stress is considered to be vital processes for the SM toxicity mechanism. We previously proved the therapeutic effect of exosomes derived from bone marrow mesenchymal stromal cells in promoting the repair of alveolar epithelial barrier and inhibiting apoptosis. However, the key functional components in exosomes and the underlying mechanisms have not been fully elaborated. This research shed light on the function of the key components of human umbilical cord mesenchymal stem cell‐derived exosomes (HMSCs‐Ex). We noted that HMSCs‐Ex‐derived miR‐199a‐5p played a vital role in reducing pneumonocyte oxidative stress and apoptosis by reducing reactive oxygen species, lipid peroxidation products and increasing the activities of antioxidant enzymes in BEAS‐2B cells and mouse models after exposure to SM for 24 h. Furthermore, we demonstrated that the overexpression of miR‐199a‐5p in HMSCs‐Ex treatment induced a further decrease of Caveolin1 and the activation of the mRNA and protein level of NRF2, HO1 and NQO1, compared with HMSCs‐Ex administration. In summary, miR‐199a‐5p was one of the key molecules in HMSCs‐Ex that attenuated SM‐associated oxidative stress via regulating CAV1/NRF2 signalling pathway. [ABSTRACT FROM AUTHOR]

Background: Sulfur mustard (SM) is a highly toxic chemical warfare agent that has caused numerous casualties during wars and conflicts in the past century. Specific antidotes or therapeutic strategies are rare due to the complicated mechanism of toxicity, which still awaits elucidation. Clinical data show that acute lung injury (ALI) is responsible for most mortality and morbidity after SM exposure. Extracellular vesicles are natural materials that participate in intercellular communication by delivering various substances and can be modified. In this study, we aim to show that extracellular vesicles derived from human umbilical cord mesenchymal stromal cells (hucMSC-EVs) could exert therapeutic effects on SM-induced ALI, and to explain the underlying mechanism of effects. Methods: MiR-146a-5p contained in hucMSC-EVs may be involved in the process of hucMSC-EVs modulating the inflammatory response to SM-induced ALI. We utilized miR-146a-5p delivered by extracellular vesicles and further modified hucMSCs with a miR-146a-5p mimic or inhibitor to collect miR-146a-5p-overexpressing extracellular vesicles (miR-146a-5p+-EVs) or miR-146a-5p-underexpressing extracellular vesicles (miR-146a-5p−-EVs), respectively. Through in vivo and in vitro experiments, we investigated the mechanism. Results: The effect of miR-146a-5p+-EVs on improving the inflammatory reaction tied to SM injury was better than that of hucMSC-EVs. We demonstrated that miR-146a-5p delivered by hucMSC-EVs targeted TRAF6 to negatively regulate inflammation in SM-induced ALI models in vitro and in vivo. Conclusion: In summary, miR-146a-5p delivered by hucMSC-EVs targeted TRAF6, causing hucMSC-EVs to exert anti-inflammatory effects in SM-induced ALI; thus, hucMSC-EVs treatment may be a promising clinical therapeutic after SM exposure. [ABSTRACT FROM AUTHOR]

This research proposed a flexible piezoresistive tactile sensor (FPTS) device with imprinted microsphere array to realize the accurate and stable acquisition of human motion data. The thickness of conductive membrane on the sensitivity of the sensor were investigated by FEM simulation, the copper microsphere array mold was prepared by multipoint imprinting process and the electromechanical response curves of piezoresistive tactile sensor consisting of Hydroxylated Multiwalled Carbon Nanotubes/Polyimide (carboxylated MWCNT/PI) composite membrane and Polydimethylsiloxane/Hydroxylated Multiwalled Carbon Nanotubes/Polyimide (PDMS/carboxylated MWCNT/PI) composite membrane with double‐sided microsphere were tested. The result shows that reduce the chord height can improve the sensitivity of the sensor. The composite structure with PDMS/carboxylated MWCNT/PI composite membrane reduces the overall stiffness of the microsphere structure, which is conducive to improve the sensitivity and minimum the detection limit of the FPTS. Multipoint imprinting technology is an efficient processing method to obtain high consistency microsphere array. The electromechanical response curves of piezoresistive tactile sensor consisting of PDMS/carboxylated MWCNT/PI composite membrane with double‐sided microsphere shows that the detection limits can reach 0.0289 kPa, and the sensitivity is 1.139 kPa−1. The sensor has high stability, especially when the wearing radius of curvature is more than 30 mm. [ABSTRACT FROM AUTHOR]