RESUMO
Hydrogen energy as the next-generation clean energy carrier has attracted the attention of both academic and industrial fields. A key limit in the current stage is the operation temperature of hydrogen fuel cells, which lies in the slow development of high-temperature and high-efficiency proton exchange membranes. Currently, much research effort has been devoted to this field, and very innovative material systems have been developed. The authors think it is the right time to make a short summary of the high-temperature proton exchange membranes (HT-PEMs), the fundamentals, and developments, which can help the researchers to clearly and efficiently gain the key information. In this paper, the development of key materials and optimization strategies, the degradation mechanism and possible solutions, and the most common morphology characterization techniques as well as correlations between morphology and overall properties have been systematically summarized.
RESUMO
Despite the great progress of current bacterially based biotherapeutics, their unsatisfying efficacy and underlying safety problems have limited their clinical application. Herein, inspired by probiotic Escherichia coli strain Nissle 1917, probiotic-derived outer membrane vesicles (OMVs) are found to serve as an effective therapeutic platform for the treatment of inflammatory bowel disease (IBD). To further enhance the therapeutic effect, the probiotic-derived OMV-encapsulating manganese dioxide nanozymes are constructed, named nanoprobiotics, which can adhere to inflamed colonic epithelium and eliminate intestinal excess reactive oxygen species in the murine IBD model. Moreover, combined with the anti-inflammatory medicine metformin, nanoprobiotics could further remold the pro-inflammatory microenvironment, improve the overall richness and diversity of the gut microbiota, and exhibit better therapeutic efficacy than commercial IBD chemotherapeutics. Importantly, insignificant overt systemic toxicity in this treatment was observed. By integrating cytokine storm calm with biotherapy, we develop a safe and effective bionanoplatform for the effective treatment of inflammation-mediated intestinal diseases.
RESUMO
A Ag(I)/PPh3-catalyzed chelation-controlled cycloisomerization of tryptamine-ynamide was developed to access the spiro[indole-3,4'-piperidine] scaffold in a racemic and diastereoselective manner. The diastereoselective products were achieved by a chiron approach. Density functional theory (DFT) calculations indicated that strong non-covalent effects between the substrate and catalyst/ligand complex stabilized the spiroindoleninium intermediate via cation-π-π interactions.
RESUMO
Phototherapy has been intensively investigated as a non-invasive cancer treatment option. However, its clinical translation is still impeded by unsatisfactory therapeutic efficacy and severe phototoxicity. To achieve high therapeutic efficiency and high security, a nanoassembly of Forster Resonance Energy Transfer (FRET) photosensitizer pairs is developed on basis of dual-mode photosensitizer co-loading and photocaging strategy. For proof-of-concept, an erythrocyte-camouflaged FRET pair co-assembly of chlorine e6 (Ce6, FRET donor) and 1,1'-dioctadecyl-3,3,3',3'-tetramethylindotricarbocyanine iodide (DiR, FRET acceptor) is investigated for breast cancer treatment. Notably, Ce6 in the nanoassemby is quenched by DiR and could be unlocked for photodynamic therapy (PDT) only when DiR is photobleached by 808-nm laser. As a result, Ce6-caused phototoxicity could be well controlled. Under cascaded laser irradiation (808-660 nm), tumor-localizing temperature rise following laser irradiation on DiR not only induces tumor cell apoptosis but also facilitates the tumor penetration of NPs, relieves tumor hypoxia, and promotes the PDT efficacy of Ce6. Such FRET pair-based nanoassembly provides a new strategy for developing multimodal phototherapy nanomedicines with high efficiency and good security.
