Oxygen activation plays a crucial role in many important chemical reactions such as oxidation of organic compounds and oxygen reduction. For developing highly active materials for oxygen activation, ...herein, we report an atomically dispersed Pt on WO3 nanoplates stabilized by in situ formed amorphous H2WO4 out‐layer and the mechanism for activating molecular oxygen. Experimental and theoretical studies demonstrate that the isolated Pt atoms coordinated with oxygen atoms from WO6 and water of H2WO4, consequently leading to optimized surface electronic configuration and strong metal–support interaction (SMSI). In exemplified reactions of butanone oxidation sensing and oxygen reduction, the atomic Pt/WO3 hybrid exhibits superior activity than those of Pt nanoclusters/WO3 and bare WO3 as well as enhanced long‐term durability. This work will provide insight into the origin of activity and stability for atomically dispersed materials, thus promoting the development of highly efficient and durable single atom‐based catalysts.
Single atom‐based catalysts: Atomically dispersed Pt species have been stabilized by an in situ formed amorphous H2WO4 layer. The Pt atoms were coordinated by oxygen atoms from the WO6 octahedra of H2WO4 and water molecules. A strong metal–support interaction was observed between the Pt atoms and the oxide atoms of H2WO4, which resulted in a superior activity and stability of the Pt atoms for the oxygen activation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
To support massive connectivity for sporadically active devices is a challenging task, as the randomness of the channel and the large number of users lead to enormous increase of communication ...overhead. Different to the existing methods that differentiate users in resources including time, frequency and code, we propose a new joint activity detection and channel estimation framework for massive multiple-input multiple-output (MIMO) systems, where angular domain information of active users is exploited to enhance activity detection and channel estimation. By exploiting the sporadic activity of users and the angular spread of the wireless signals, the activity detection and channel estimation is formulated as a compressive sensing problem with multiple measurement vectors, which has a simultaneously row-sparse and clustered sparse structure. The sizes and positions of the nonzero clusters are arbitrary, which brings new challenges for algorithm derivation. To this end, we develop new algorithms based on sparse Bayesian learning, where novel hyper-priors are proposed to capture the structural signal characteristics, and appropriate approximations are employed to facilitate algorithm derivations. Numerical experiments demonstrate the improved activity detection and channel estimation performance of the proposed approach in comparison to the existing methods.
Anaplasma capra is an emerging tickborne human pathogen initially recognized in China in 2015; it has been reported in ticks and in a wide range of domestic and wild animals worldwide. We describe ...whole-genome sequences of 2 A. capra strains from metagenomic sequencing of purified erythrocytes from infected goats in China. The genome of A. capra was the smallest among members of the genus Anaplasma. The genomes of the 2 A. capra strains contained comparable G+C content and numbers of pseudogenes with intraerythrocytic Anaplasma species. The 2 A. capra strains had 54 unique genes. The prevalence of A. capra was high among goats in the 2 endemic areas. Phylogenetic analyses revealed that the A. capra strains detected in this study were basically classified into 2 subclusters with those previously detected in Asia. Our findings clarify details of the genomic characteristics of A. capra and shed light on its genetic diversity.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The incidence of hepatocellular carcinoma is rising worldwide. It is predicted that nearly half of the early-stage hepatocellular carcinoma (E-HCC) patients will develop recurrence. Dysregulated pH, ...a hallmark of E-HCC, is correlated with poor prognosis. The acidic microenvironment has been shown to promote the release of exosomes, the membrane vesicles recognized as intercellular communicators associated with tumor progression, recurrence, and metastasis. We, therefore, aimed to identify exosomes induced by acidic microenvironment that may regulate E-HCC progression and to explore their mechanisms and clinical significance in E-HCCs.
miRNA microarray analysis and LASSO logistic statistic model were used to identify the main functional exosomal miRNAs. Invasion and scratch assays were performed to examine the migration and invasion of HCC cells. Immunoblotting and immunofluorescence were employed to detect the epithelial-to-mesenchymal transition (EMT) in HCC cells. Chromatin immunoprecipitation (ChIP) was used to analyze the binding of HIF-1α and HIF-2α to promoter regions of miR-21 and miR-10b.
The acidic microenvironment in HCC was correlated with poor prognosis of patients. Exosomes from HCC cells cultured in the acidic medium could promote cell proliferation, migration, and invasion of recipient HCC cells. We identified miR-21 and miR-10b as the most important functional miRNAs in acidic HCC-derived exosomes. Also, the acidic microenvironment triggered the activation of HIF-1α and HIF-2α and stimulated exosomal miR-21 and miR-10b expression substantially promoting HCC cell proliferation, migration, and invasion both
and
. In E-HCC patients, serum exosomal miR-21 and miR-10b levels were associated with advanced tumor stage and HIF-1α and HIF-2α expression and were independent prognostic factors for disease-free survival of E-HCC patients. Most importantly, we developed a nano-drug to target exosomal miR-21 and/or miR-10b and examined its therapeutic effects against HCC
.
Our findings suggested that the exosomal miR-21 and miR-10b induced by acidic microenvironment in HCC promote cancer cell proliferation and metastasis and may serve as prognostic molecular markers and therapeutic targets for HCC.
The excessive emission of CO
2
has caused many environmental issues and is severely threatening the eco-system. CO
2
electroreduction reaction (CO
2
RR) that driven by sustainable power is an ideal ...route for realizing the net reduction of CO
2
and carbon recycle. Developing efficient electrocatalysts with low cost and high performance is critical for the wide applications of CO
2
RR electrolysis. Among the various explored CO
2
RR catalysts, non-noble metal (NNM)-based nanomaterials have drawn increasing attentions due to the remarkable performance and low cost. In this mini-review, the recent advances of NNM-based CO
2
RR catalysts are summarized, and the catalysts are classified based on their corresponding reduction products. The preparation strategies for engineering the electrocatalysts are introduced, and the relevant CO
2
RR mechanisms are discussed in detail. Finally, the current challenges in CO
2
RR research are presented, and some perspectives are proposed for the future development of CO
2
RR technology. This mini-review introduces the recent advances and frontiers of NNM-based CO
2
RR catalysts, which should shed light on the further exploration of efficient CO
2
RR electrocatalysts.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Ammonia, one of the major limiting environment factors in aquaculture, may pose a threat to the shrimp growth, reproduction and survival. In this study, to understand molecular differences of ...transcriptomic and metabolomic responses and investigate the tolerance mechanisms underlying ammonia stress in Litopenaeus vannamei, ammonia-tolerant family (LV-AT) and ammonia-sensitive family (LV-AS) of these two extreme families were exposed to high-concentration (NH4Cl, 46 mg/L) ammonia for 24 h. The comparative transcriptome analysis between ammonia-treated and control (LV-C) groups revealed involvement of immune defense, cytoskeleton remodeling, antioxidative system and metabolic pathway in ammonia-stress response of L. vannamei. Likewise, metabolomics analysis showed that ammonia exposure could disturb amino acid metabolism, nucleotide metabolism and lipid metabolism, with metabolism related-genes changed according to RNA-seq analysis. The comparison of metabolite and transcript profiles between LV-AT and LV-AS indicated that LV-AT used the enhanced glycolysis and tricarboxylic acid (TCA) cycle strategies for energy supply and ammonia excretion to adapt high-concentration ammonia. Furthermore, some of genes involved in the detoxification and ammonia excretion were highly expressed in LV-AT. We speculate that the higher ability of ammonia excretion and detoxification and the accelerated energy metabolism for energy supplies might be the adaptive strategies for LV-AT relative to LV-AS after ammonia stress. Collectively, the combination of transcriptomics and metabolomics results will greatly contribute to incrementally understand the stress responses on ammonia exposure to L. vannamei and supply molecular level support for evaluating the environmental effects of ammonia on aquatic organisms. The results further constitute new sights on the potential molecular mechanisms of ammonia adaptive strategies in shrimps at the transcriptomics and metabolomics levels.
•Transcriptomic and metabolomic responses to high-concentration of ammonia were studied in L. vannamei.•Ammonia exposure influences immune defense, cytoskeleton remodeling, antioxidative system and metabolic pathway.•Ammonia exposure disturbs the amino acid metabolism, lipid metabolism and nucleotide metabolism.•Higher ability of excretion and detoxification and accelerated energy metabolism might be related to ammonia tolerance.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Host-associated microbial communities play an important role in the fitness of insect hosts. However, the factors shaping microbial communities in wild populations, including genetic background, ...ecological factors, and interactions among microbial species, remain largely unknown.
Here, we surveyed microbial communities of the small brown planthopper (SBPH, Laodelphax striatellus) across 17 geographical populations in China and Japan by using 16S rRNA amplicon sequencing. Using structural equation models (SEM) and Mantel analyses, we show that variation in microbial community structure is likely associated with longitude, annual mean precipitation (Bio12), and mitochondrial DNA variation. However, a Wolbachia infection, which is spreading to northern populations of SBPH, seems to have a relatively greater role than abiotic factors in shaping microbial community structure, leading to sharp decreases in bacterial taxon diversity and abundance in host-associated microbial communities. Comparative RNA-Seq analyses between Wolbachia-infected and -uninfected strains indicate that the Wolbachia do not seem to alter the immune reaction of SBPH, although Wolbachia affected expression of metabolism genes.
Together, our results identify potential factors and interactions among different microbial species in the microbial communities of SBPH, which can have effects on insect physiology, ecology, and evolution. Video Abstract.
Recently, long noncoding RNAs (lncRNAs) were demonstrated to play important regulatory roles in biological processes and cancer biology. However, the overall pathophysiological contribution of ...lncRNAs to gastric cancer (GC) remains largely unknown. In this study, differentially expressed lncRNAs in GC and paired adjacent normal tissue samples were identified by microarray and were validated using quantitative real‐time polymerase chain reaction (qRT‐PCR). One particular lncRNA, tumour suppressor candidate 7 (TUSC7), was analyzed in sequential large cohorts, and the Kaplan–Meier method with the log‐rank test for comparisons was used to analyse the survival data. The results indicated that TUSC7 was downregulated in GC samples and was an independent prognostic indicator of disease‐free survival (DFS) and disease‐specific survival (DSS) in GC patients. Applying loss‐of‐function and gain‐of‐function approaches, we determined that TUSC7 suppressed tumour cell growth in vitro and in vivo. Furthermore, we showed that TUSC7 was a direct transcriptional target of p53 via interaction of p53 with the putative p53‐response element in the upstream region of TUSC7. Finally, we demonstrated reciprocal repression between TUSC7 and miR‐23b; in contrast to TUSC7, miR‐23b promoted cell growth. The results indicated that TUSC7 is a p53‐regulated tumour suppressor that acts in part by repressing miR‐23b and that TUSC7 may be a key regulatory hub in GC.
What's new?
Long noncoding RNA expression could predict gastric cancer survival, new data suggest. It's been shown previously that these transcripts can function as tumor suppressors, and in this paper the authors investigate lncRNAs in gastric cancer. First, they identified lncRNAs that were expressed differently in cancer cells than healthy ones. By performing a cohort analysis they showed that patients with one particular lncRNA, called TUSC7, had a greater chance of survival. They then demonstrated that p53 regulates TUSC7 transcription, and that TUSC7 represses miR‐23b, which spurs cell growth. Thus, TUSC7 may act as a tumor suppressor.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Some temperate tree species mitigate the negative impacts of frost-induced xylem cavitation by restoring impaired hydraulic function via positive pressures, and may therefore be more resistant to ...frost fatigue (the phenomenon that post-freezing xylem becomes more susceptible to hydraulic dysfunction) than nonpressure-generating species. We test this hypothesis and investigate underlying anatomical/physiological mechanisms.
Using a common garden experiment, we studied key hydraulic traits and detailed xylem anatomical characteristics of 18 sympatric tree species. These species belong to three functional groups, that is, one generating both root and stem pressures (RSP), one generating only root pressure (RP), and one unable to generate such pressures (NP).
The three functional groups diverged substantially in hydraulic efficiency, resistance to drought-induced cavitation, and frost fatigue resistance. Most notably, RSP and RP were more resistant to frost fatigue than NP, but this was at the cost of reduced hydraulic conductivity for RSP and reduced resistance to drought-induced cavitation for RP.
Our results show that, in environments with strong frost stress: these groups diverge in hydraulic functioning following multiple trade-offs between hydraulic efficiency, resistance to drought and resistance to frost fatigue; and how differences in anatomical characteristics drive such divergence across species.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NMLJ, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Tryptophan (Trp) metabolism is associated with diverse biological processes, including nerve conduction, inflammation, and the immune response. The majority of free Trp is broken down through the ...kynurenine (Kyn) pathway (KP), in which indoleamine-2,3-dioxygenase (IDO) and tryptophan-2,3-dioxygenase (TDO) catalyze the rate-limiting step. Clinical studies have demonstrated that Trp metabolism promotes tumor progression due to modulation of the immunosuppressive microenvironment through multiple mechanisms. In this process, IDO-expressing dendritic cells (DCs) exhibit tolerogenic potential and orchestrate T cell immune responses. Various signaling molecules control IDO expression, initiating the immunoregulatory pathway of Trp catabolism. Based on these characteristics, KP enzymes and catabolites are emerging as significant prognostic indicators and potential therapeutic targets of cancer. The physiological and oncologic roles of Trp metabolism are briefly summarized here, along with great challenges for treatment strategies.
•Trp metabolism imparts cancer cells with enhanced metastatic capacity by modulating the immunosuppressive microenvironment.•IDO-expressing dendritic cells exhibit tolerogenic potential and orchestrate T cell immune responses.•IDO and TDO are appealing targets in cancer therapy and clinical trials of combination strategies are underway.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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