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Although diverse uranium (U) adsorbents have been explored, it is still a great challenge for high-efficient uranium extraction form seawater. Herein a wood-mimetic oriented porous Ti3C2Tx-MXene/gelatin hydrogel (MGH) has been explored through growing directional ice crystals cooled by liquid nitrogen and subsequently forming pores by freeze-dry (Ice-template) method, for ultrafast and high-efficient U-adsorption from seawater with great enhancement by both electric field and sunlight. Different from disperse Ti3C2Tx-MXene powder, this MGH not only can be easily utilized but also can own ultrahigh specific surface area for high-efficient U-adsorption. The U-adsorbing capacity of this MGH (10 mg) can reach 4.17 mg·g−1 after only 1 week in 100 kg of seawater, which is outstanding in existing adsorbents. Furthermore, on the positive pole of 0.4 V direct current source or under 1-sun irradiation, the U-adsorbing capacity of the MGH can increase by 57.11% and 13.57%, respectively. Most importantly, the U-adsorption of this hydrogel can be greatly enhanced by simultaneously using the above two methods, which can increase the U-adsorbing capacity by 79.95% reaching 7.51 mg·g−1. This work provides a new biomimetic porous MXene-based hydrogel for electric field/sunlight bi-enhanced high-efficient U-extraction from seawater, which will inspire new strategy to design novel U-adsorbents and systems.

Although metal–organic frameworks (MOFs) own excellent uranium adsorption capacity but are still difficult to conveniently extract uranium from seawater due to the discrete powder state. In this study, a new MOF-based macroporous membrane has been explored, which can high-efficiently extract uranium through continuously filtering seawater. Through modifying the UiO-66 with poly(amidoxime) (PAO), it can disperse well in a N,N-dimethylformamide solution of graphene oxide and cotton fibers. Then, the as-prepared super-hydrophilic MOF-based macroporous membrane can be fabricated after simple suction filtration. Compared with nonmodified MOFs, this UiO-66@PAO can be dispersed uniformly in the membrane because it can stabilize well in the solution, which have largely enhanced uranium adsorbing capacity owing to the modified PAO. Last but not least, different from powder MOFs, this UiO-66@PAO membrane provides the convenient and continuously uranium adsorbing process. As a consequence, the uranium extraction capacity of this membrane can reach 579 mg·g−1 in 32 ppm U-added simulated seawater for only 24 h. Most importantly, this UiO-66@PAO membrane (100 mg) can remove 80.6% uranyl ions from 5 L seawater after 50 filtering cycles. This study provides a universal method to design and fabricate a new MOF-based adsorbent for high-efficient uranium recovery from seawater.

Dynamic covalent bond-based shape memory polymers (DCB-SMPs) are one of most important SMPs which have a wide potential application prospect. Different from common strong covalent bonds, DCBs own relatively weak bonding energy, similarly to the supramolecular interactions of noncovalent bonds, and can dynamically combine and dissociate these bonds. DCB-SMP solids, which can be designed to respond for different stimuli, can provide excellent self-healing, good reprocessability, and high mechanical performance, because DCBs can obtain dynamic cross-linking without sacrificing ultrahigh fixing rates. Furthermore, besides DCB-SMP solids, DCB-SMP hydrogels with responsiveness to various stimuli also have been developed recently, which have special biocompatible soft/wet states. Particularly, DCB-SMPs can be combined with emerging 3D-printing techniques to design various original shapes and subsequently complex shape recovery. This review has summarized recent research studies about SMPs based on various DCBs including DCB-SMP solids, DCB-SMP hydrogels, and the introduction of new 3D-printing techniques using them. Last but not least, the advantages/disadvantages of different DCB-SMPs have been analyzed via polymeric structures and the future development trends in this field have been predicted.

Background: In lung transplantation (LTx) surgery, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) can provide mechanical circulatory support to patients with cardiopulmonary failure. However, the use of heparin in the administration of ECMO can increase blood loss during LTx. This study aimed to evaluate the safety of heparin-free V-A ECMO strategies. Methods: From September 2019 to April 2022, patients who underwent lung transplantation at the First Affiliated Hospital of Guangzhou Medical University were retrospectively reviewed. A total of 229 patients were included, including 117 patients in the ECMO group and 112 in the non-ECMO group. Result: There was no significant difference in the incidence of thrombus events and bleeding requiring reoperation between the two groups. The in-hospital survival rate after single lung transplantation (SLTx) was 81.08%in the ECMO group and 85.14% in the Non-ECMO group, (P = 0.585). The in-hospital survival rate after double lung transplantation (DLTx) was 80.00% in the ECMO group and 92.11% in the Non-ECMO groups (P = 0.095). Conclusions: In conclusion, the findings of this study suggest that the heparin-free V-A ECMO strategy in lung transplantation is a safe approach that does not increase the incidence of perioperative thrombotic events or bleeding requiring reoperation. [ABSTRACT FROM AUTHOR]

Biomass-related airborne fine particulate matter (PM2.5) is an important risk factor for chronic obstructive pulmonary disease (COPD). Macrophage polarization has been reported to be involved in PM2.5-induced COPD, but the dynamic characteristics and underlying mechanism of this process remain unclear. Our study established a PM2.5-induced COPD mouse model and revealed that M2 macrophages predominantly presented after 4 and 6 months of PM2.5 exposure, during which a notable increase in MMP12 was observed. Single cell analysis of lung tissues from COPD patients and mice further revealed that M2 macrophages were the dominant macrophage subpopulation in COPD, with MMP12 being involved as a hub gene. In vitro experiments further demonstrated that PM2.5 induced M2 polarization and increased MMP12 expression. Moreover, we found that PM2.5 increased IL-4 expression, STAT6 phosphorylation and nuclear translocation. Nuclear pSTAT6 then bound to the MMP12 promoter region. Furthermore, the inhibition of STAT6 phosphorylation effectively abrogated the PM2.5-induced increase in MMP12. Using a coculture system, we observed a significantly reduced level of E-cadherin in alveolar epithelial cells cocultured with PM2.5-exposed macrophages, while the decrease in E-cadherin was reversed by the addition of an MMP12 inhibitor to the co-culture system. Taken together, these findings indicated that PM2.5 induced M2 macrophage polarization and MMP12 upregulation via the IL-4/STAT6 pathway, which resulted in alveolar epithelial barrier dysfunction and excessive extracellular matrix (ECM) degradation, and ultimately led to COPD progression. These findings may help to elucidate the role of macrophages in COPD, and suggest promising directions for potential therapeutic strategies., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)