Exploring high‐efficiency and stable halide perovskite‐based photocatalysts for the selective reduction of CO2 to methane is a challenge because of the intrinsic photo‐ and chemical instability of ...halide perovskites. In this study, halide perovskites (Cs3Bi2Br9 and Cs2AgBiBr6) were grown in situ in mesoporous TiO2 frameworks for an efficient CO2 reduction. Benchmarked CH4 production rates of 32.9 and 24.2 μmol g−1 h−1 with selectivities of 88.7 % and 84.2 %, were achieved, respectively, which are better than most reported halide perovskite photocatalysts. Focused ion‐beam sliced‐imaging techniques were used to directly image the hyperdispersed perovskite nanodots confined in mesopores with tunable sizes ranging from 3.8 to 9.9 nm. In situ X‐ray photoelectronic spectroscopy and Kelvin probe force microscopy showed that the built‐in electric field between the perovskite nanodots and mesoporous titania channels efficiently promoted photo‐induced charge transfer. Density functional theory calculations indicate that the high methane selectivity was attributed to the Bi‐adsorption‐mediated hydrogenation of *CO to *HCO that dominates CO desorption.
Halide perovskites (Cs3Bi2Br9, Cs2AgBiBr6) are grown in situ in a mesoporous titania framework for efficient CO2 reduction reaction (CO2RR). A benchmarked production rate of CH4 (32.9 and 24.2 μmol g−1 h−1) is achieved with selectivity values of 88.7 % and 84.2 %, respectively. In situ X‐ray photoelectronic spectroscopy and Kelvin probe force microscopy reveal that the inner surface built‐in electric field between the perovskite nanodots and mesoporous titania channels can efficiently promote photo‐induced charge transfer.
Metastasis-associated recurrence is the major cause of poor prognosis in hepatocellular carcinoma (HCC), however, the underlying mechanisms remain largely elusive. In this study, we report that ...expression of choroideremia-like (CHML) is increased in HCC, associated with poor survival, early recurrence and more satellite nodules in HCC patients. CHML promotes migration, invasion and metastasis of HCC cells, in a Rab14-dependent manner. Mechanism study reveals that CHML facilitates constant recycling of Rab14 by escorting Rab14 to the membrane. Furthermore, we identify several metastasis regulators as cargoes carried by Rab14-positive vesicles, including Mucin13 and CD44, which may contribute to metastasis-promoting effects of CHML. Altogether, our data establish CHML as a potential promoter of HCC metastasis, and the CHML-Rab14 axis may be a promising therapeutic target for HCC.
Non-receptor protein tyrosine phosphatases (PTPNs) are a set of enzymes involved in the tyrosyl phosphorylation. The present study intended to clarify the associations between the expression patterns ...of PTPN family members, and diagnosis as well as the prognosis of digestive tract cancers.
Oncomine and Ualcan were used to analyze PTPN expressions. Data from The Cancer Genome Atlas (TCGA) were downloaded through UCSC Xena for validation and to explore the relationship of the PTPN expression with diagnosis, clinicopathological parameters and survival of digestive tract cancers. Gene ontology enrichment analysis was conducted using the DAVID database. The gene-gene interaction network was performed by GeneMANIA and the protein-protein interaction (PPI) network was built using STRING portal coupled with Cytoscape. The expression of differentially expressed PTPNs in cancer cell lines were explored using CCLE. Moreover, by histological verification, the expression of four PTPNs in digestive tract cancers were further analyzed.
Most PTPN family members were associated with digestive tract cancers according to Oncomine, Ualcan and TCGA data. Several PTPN members were differentially expressed in digestive tract cancers. For esophageal carcinoma (ESCA), PTPN1 and PTPN12 levels were correlated with incidence; PTPN20 was associated with poor prognosis. For stomach adenocarcinoma (STAD), PTPN2 and PTPN12 levels were correlated with incidence; PTPN3, PTPN5, PTPN7, PTPN11, PTPN13, PTPN14, PTPN18 and PTPN23 were correlated with pathological grade; PTPN20 expression was related with both TNM stage and N stage; PTPN22 was associated with T stage and pathological grade; decreased expression of PTPN5 and PTPN13 implied worse overall survival of STAD, while elevated PTPN6 expression indicated better prognosis. For colorectal cancer (CRC), PTPN2, PTPN21 and PTPN22 levels were correlated with incidence; expression of PTPN5, PTPN12, and PTPN14 was correlated with TNM stage and N stage; high PTPN5 or PTPN7 expression was associated with increased hazards of death. CCLE analyses showed that in esophagus cancer cell lines, PTPN1, PTPN4 and PTPN12 were highly expressed; in gastric cancer cell lines, PTPN2 and PTPN12 were highly expressed; in colorectal cancer cell lines, PTPN12 was highly expressed while PTPN22 was downregulated. Results of histological verification experiment showed differential expressions of PTPN22 in CRC, and PTPN12 in GC and CRC.
Members of PTPN family were differentially expressed in digestive tract cancers. Correlations were found between PTPN genes and clinicopathological parameters of patients. Expression of PTPN12 was upregulated in both STAD and CRC, and thus could be used as a diagnostic biomarker. Differential expression of PTPN12 in GC and CRC, and PTPN22 in CRC were presented in our histological verification experiment.
Background and Purpose
Atrial metabolic remodelling is critical for the process of atrial fibrillation (AF). The PPAR‐α/sirtuin 1 /PPAR co‐activator α (PGC‐1α) pathway plays an important role in ...maintaining energy metabolism. However, the effect of the PPAR‐α agonist fenofibrate on AF is unclear. Therefore, the aim of this study was to determine the effect of fenofibrate on atrial metabolic remodelling in AF and explore its possible mechanisms of action.
Experimental Approach
The expression of metabolic proteins was examined in the left atria of AF patients. Thirty‐two rabbits were divided into sham, AF (pacing with 600 beats·min−1 for 1 week), fenofibrate treated (pretreated with fenofibrate before pacing) and fenofibrate alone treated (for 2 weeks) groups. HL‐1 cells were subjected to rapid pacing in the presence or absence of fenofibrate, the PPAR‐α antagonist GW6471 or sirtuin 1‐specific inhibitor EX527. Metabolic factors, circulating biochemical metabolites, atrial electrophysiology, adenine nucleotide levels and accumulation of glycogen and lipid droplets were assessed.
Key Results
The PPAR‐α/sirtuin 1/PGC‐1α pathway was significantly inhibited in AF patients and in the rabbit/HL‐1 cell models, resulting in a reduction of key downstream metabolic factors; this effect was significantly restored by fenofibrate. Fenofibrate prevented the alterations in circulating biochemical metabolites, reduced the level of adenine nucleotides and accumulation of glycogen and lipid droplets, reversed the shortened atrial effective refractory period and increased risk of AF.
Conclusion and Implications
Fenofibrate inhibited atrial metabolic remodelling in AF by regulating the PPAR‐α/sirtuin 1/PGC‐1α pathway. The present study may provide a novel therapeutic strategy for AF.
Cyanobacterial harmful algal blooms (cyanoHABs) in freshwater lakes across the globe are often combined with other stressors. Pharmaceutical pollution, especially antibiotics in water bodies, poses a ...potential hazard in aquatic ecosystems. However, how antibiotics influence the risk of cyanoHABs remains unclear. Here, we investigated the effects of norfloxacin (NOR), one of the most widely used antibiotics globally, to a bloom‐forming cyanobacterium (Microcystis aeruginosa) and a common green alga (Scenedesmus quadricauda), under both mono‐ and coculture conditions. Taxon‐specific responses to NOR were evaluated in monoculture. In addition, the growth rate and change in ratio of cyanobacteria to green algae when cocultured with exposure to NOR were determined. In monocultures of Microcystis, exposure to low concentrations of NOR resulted in decreases in biomass, chlorophyll a and soluble protein content, while superoxide anion content and superoxide dismutase activity increased. However, NOR at high concentration only slightly affected Scenedesmus. During the co‐culture trials of Microcystis and Scenedesmus, the 5 μg · L−1 NOR treatment increased the ratio of Microcystis to co‐cultured Scenedesmus by 47.2%. Meanwhile, although Scenedesmus growth was enhanced by 4.2% under NOR treatment in monoculture, it was conversely inhibited by 63.4% and 38.2% when co‐cultured with Microcystis with and without NOR, respectively. Our results indicate that antibiotic pollution has a potential risk to enhance the perniciousness of cyanoHABs by disturbing interspecific interaction between cyanobacteria and green algae. These results reinforce the need for scientists and managers to consider the influence of xenobiotics in shaping the outcome of interactions among multiple species in aquatic ecosystems.
Downregulating programmed cell death ligand 1(PD‐L1) protein levels in tumor cells is an effective way to achieve immune system activation for oncology treatment, but current strategies are ...inadequate. Here, we design a caged peptide‐AIEgen probe (GCP) to self‐assemble with miR‐140 forming GCP/miR‐140 nanoparticles. After entering tumor cells, GCP/miR‐140 disassembles in the presence of Cathepsin B (CB) and releases caged GO203 peptide, miR‐140 and PyTPA. Peptide decages in the highly reductive intracellular environment and binds to mucin 1 (MUC1), thereby downregulating the expression of PD‐L1. Meanwhile, miR‐140 reduces PD‐L1 expression by targeting downregulation of PD‐L1 mRNA. Under the action of PyTPA‐mediated photodynamic therapy (PDT), tumor‐associated antigens are released, triggering immune cell attack on tumor cells. This multiple mechanism‐based strategy of deeply downregulating PD‐L1 in tumor cells activates the immune system and thus achieves effective immunotherapy.
In tumor cells, a caged peptide‐AIEgen probe self‐assembled with miR‐140 could release the GO203 peptide binding to MUC1 and miR‐140 degrading the PD‐L1 mRNA, thus, achieving the deep downregulation of the PD‐L1 expression. Subsequently, activated immune cells by PDT‐induced release of TAAs would achieve more effective immunotherapy.
Herein, visible‐light‐driven iron‐catalyzed nitrene transfer reactions with dioxazolones for intermolecular C(sp3)‐N, N=S, and N=P bond formation are described. These reactions occur with ...exogenous‐ligand‐free process and feature satisfactory to excellent yields (up to 99 %), an ample substrate scope (109 examples) under mild reaction conditions. In contrast to intramolecular C−H amidations strategies, an intermolecular regioselective C−H amidation via visible‐light‐induced nitrene transfer reactions is devised. Mechanistic studies indicate that the reaction proceeds via a radical pathway. Computational studies show that the decarboxylation of dioxazolone depends on the conversion of ground sextet state dioxazolone‐bounding iron species to quartet spin state via visible‐light irradiation.
Visible‐light‐driven iron‐catalyzed nitrene transfer reactions with dioxazolones are used for intermolecular C(sp3)‐N, N=S and N=P bond formation. The key acyl nitrene iron intermediate is formed by conversion of the ground sextet state of dioxazolone‐bounding iron species to quartet spin state under visible‐light irradiation.
Background
To reveal detailed histopathological changes, virus distributions, immunologic properties and multi‐omic features caused by SARS‐CoV‐2 in the explanted lungs from the world's first ...successful lung transplantation of a COVID‐19 patient.
Materials and methods
A total of 36 samples were collected from the lungs. Histopathological features and virus distribution were observed by optical microscope and transmission electron microscope (TEM). Immune cells were detected by flow cytometry and immunohistochemistry. Transcriptome and proteome approaches were used to investigate main biological processes involved in COVID‐19‐associated pulmonary fibrosis.
Results
The histopathological changes of the lung tissues were characterized by extensive pulmonary interstitial fibrosis and haemorrhage. Viral particles were observed in the cytoplasm of macrophages. CD3+CD4− T cells, neutrophils, NK cells, γ/δ T cells and monocytes, but not B cells, were abundant in the lungs. Higher levels of proinflammatory cytokines iNOS, IL‐1β and IL‐6 were in the area of mild fibrosis. Multi‐omics analyses revealed a total of 126 out of 20,356 significant different transcription and 114 out of 8,493 protein expression in lung samples with mild and severe fibrosis, most of which were related to fibrosis and inflammation.
Conclusions
Our results provide novel insight that the significant neutrophil/ CD3+CD4− T cell/ macrophage activation leads to cytokine storm and severe fibrosis in the lungs of COVID‐19 patient and may contribute to a better understanding of COVID‐19 pathogenesis.
Auxin plays crucial roles in multiple developmental processes, such as embryogenesis, organogenesis, cell determination and division, as well as tropic responses. These processes are finely ...coordinated by the auxin, which requires the polar distribution of auxin within tissues and cells. The intercellular directionality of auxin flow is closely related to the asymmetric subcellular location of PIN-FORMED (PIN) auxin efflux transporters. All PIN proteins have a conserved structure with a central hydrophilic loop domain, which harbors several phosphosites targeted by a set of protein kinases. The activities of PIN proteins are finely regulated by diverse endogenous and exogenous stimuli at multiple layers-including transcriptional and epigenetic levels, post-transcriptional modifications, subcellular trafficking, as well as PINs' recycling and turnover-to facilitate the developmental processes in an auxin gradient-dependent manner. Here, the recent advances in the structure, evolution, regulation and functions of PIN proteins in plants will be discussed. The information provided by this review will shed new light on the asymmetric auxin-distribution-dependent development processes mediated by PIN transporters in plants.
Squalene, a valuable acyclic triterpene, can be used as a chemical commodity for pharmacology, flavor, and biofuel industries. Microbial production of squalene has been of great interest due to its ...limited availability, and increasing prices extracted from animal and plant tissues. Here we report genetic perturbations that synergistically improve squalene production in Saccharomyces cerevisiae. As reported previously, overexpression of a truncated HMG‐CoA reductase 1 (tHMG1) led to the accumulation 20‐fold higher squalene than a parental strain. In order to further increase squalene accumulation in the tHMG1 overexpressing yeast, we introduced genetic perturbations—known to increase lipid contents in yeast—to enhance squalene accumulation as lipid body is a potential storage of squalene. Specifically, DGA1 coding for diacylglycerol acyltranferase was overexpressed to enhance lipid biosynthesis, and POX1 and PXA2 coding for acyl‐CoA oxidase and a subunit of peroxisomal ABC transporter were deleted to reduce lipid β‐oxidation. Simultaneous overexpression of tHMG1 and DGA1 coding for rate‐limiting enzymes in the mevalonate and lipid biosynthesis pathways led to over 250‐fold higher squalene accumulation than a control strain. However, deletion of POX1 and PXA2 in the tHMG1 overexpressing yeast did not improve squalene accumulation additionally. Fed‐batch fermentation of the tHMG1 and DGA1 co‐overexpressing yeast strain resulted in the production of squalene at a titer of 445.6 mg/L in a nitrogen‐limited minimal medium. This report demonstrates that increasing storage capacity for hydrophobic compounds can enhance squalene production, suggesting that increasing lipid content is an effective strategy to overproduce a hydrophobic molecule in yeast.
This study focused on the genetic perturbations eliciting improved lipid production and enhanced squalene accumulation in Saccharomyces cerevisiae. The engineered strains, with simultaneous overexpression of tHMG1 and DGA1 coding for rate‐limiting enzymes in the mevalonate and lipid biosynthesis pathways, showed over 250‐fold higher squalene accumulation than a control strain. The results indicated that increasing storage capacity for hydrophobic compounds enhances squalene production.
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