A facile anisotropic surface modification and etching strategy is presented for the synthesis of hollow structured ZIF‐67 nanoframes. The strategy uses structural and compositional distinctions ...between each crystallographic facet of truncated rhombic dodecahedrons ZIF‐67 (tZIF‐67 RDs) and the moderate coordinating and etching effects of cyanuric acid (CA). The CA can anisotropically modify and protect the {110} facets from etching, causing the six {100} facets be selectively etched via an inside‐out manner, and finally forming the hollow nanoframes. The surface‐modified hollow tZIF‐67 RDs can be facet‐selectively etched by metal salts in an outside‐in manner to give metal‐doped tZIF‐67 nanoframes. After calcination, the metal‐tZIF‐67 hybrids are converted into metal‐Co alloy/C composite catalysts with hollow nanoframed structures. The PtCo/C catalyst with only 5.9 wt % Pt exhibits high catalytic activities and stabilities in the hydrogen evolution reaction (HER) in acidic solutions.
CA molecules can anisotropically modify and protect the {110} facets of the tZIF‐67 crystal from etching, causing the six {100} facets be selectively etched via an inside‐out manner, and finally forming the hollow nanoframes. The surface modified hollow tZIF‐67 can further be facet‐selectively etched by metal salts in an outside‐in manner to give metal‐doped tZIF‐67 nanoframes.
Patients with locoregionally advanced nasopharyngeal carcinoma have a high risk of disease relapse, despite a high proportion of patients attaining complete clinical remission after receiving ...standard-of-care treatment (ie, definitive concurrent chemoradiotherapy with or without induction chemotherapy). Additional adjuvant therapies are needed to further reduce the risk of recurrence and death. However, the benefit of adjuvant chemotherapy for nasopharyngeal carcinoma remains controversial, highlighting the need for more effective adjuvant treatment options.
This multicentre, open-label, parallel-group, randomised, controlled, phase 3 trial was done at 14 hospitals in China. Patients (aged 18–65 years) with histologically confirmed, high-risk locoregionally advanced nasopharyngeal carcinoma (stage III–IVA, excluding T3–4N0 and T3N1 disease), no locoregional disease or distant metastasis after definitive chemoradiotherapy, an Eastern Cooperative Oncology Group performance status of 0 or 1, sufficient haematological, renal, and hepatic function, and who had received their final radiotherapy dose 12–16 weeks before randomisation, were randomly assigned (1:1) to receive either oral metronomic capecitabine (650 mg/m2 body surface area twice daily for 1 year; metronomic capecitabine group) or observation (standard therapy group). Randomisation was done with a computer-generated sequence (block size of four), stratified by trial centre and receipt of induction chemotherapy (yes or no). The primary endpoint was failure-free survival, defined as the time from randomisation to disease recurrence (distant metastasis or locoregional recurrence) or death due to any cause, in the intention-to-treat population. Safety was assessed in all patients who received at least one dose of capecitabine or who had commenced observation. This trial is registered with ClinicalTrials.gov, NCT02958111.
Between Jan 25, 2017, and Oct 25, 2018, 675 patients were screened, of whom 406 were enrolled and randomly assigned to the metronomic capecitabine group (n=204) or to the standard therapy group (n=202). After a median follow-up of 38 months (IQR 33–42), there were 29 (14%) events of recurrence or death in the metronomic capecitabine group and 53 (26%) events of recurrence or death in the standard therapy group. Failure-free survival at 3 years was significantly higher in the metronomic capecitabine group (85·3% 95% CI 80·4–90·6) than in the standard therapy group (75·7% 69·9–81·9), with a stratified hazard ratio of 0·50 (95% CI 0·32–0·79; p=0·0023). Grade 3 adverse events were reported in 35 (17%) of 201 patients in the metronomic capecitabine group and in 11 (6%) of 200 patients in the standard therapy group; hand-foot syndrome was the most common adverse event related to capecitabine (18 9% patients had grade 3 hand-foot syndrome). One (<1%) patient in the metronomic capecitabine group had grade 4 neutropenia. No treatment-related deaths were reported in either group.
The addition of metronomic adjuvant capecitabine to chemoradiotherapy significantly improved failure-free survival in patients with high-risk locoregionally advanced nasopharyngeal carcinoma, with a manageable safety profile. These results support a potential role for metronomic chemotherapy as an adjuvant therapy in the treatment of nasopharyngeal carcinoma.
The National Natural Science Foundation of China, the Key-Area Research and Development Program of Guangdong Province, the Natural Science Foundation of Guangdong Province, the Innovation Team Development Plan of the Ministry of Education, and the Overseas Expertise Introduction Project for Discipline Innovation.
For the Chinese translation of the abstract see Supplementary Materials section.
Abiotic stress severely influences plant growth and development. MYB transcription factors (TFs), which compose one of the largest TF families, play an important role in abiotic stress responses.
We ...identified 139 soybean MYB-related genes; these genes were divided into six groups based on their conserved domain and were distributed among 20 chromosomes (Chrs). Quantitative real-time PCR (qRT-PCR) indicated that GmMYB118 highly responsive to drought, salt and high temperature stress; thus, this gene was selected for further analysis. Subcellular localization revealed that the GmMYB118 protein located in the nucleus. Ectopic expression (EX) of GmMYB118 increased tolerance to drought and salt stress and regulated the expression of several stress-associated genes in transgenic Arabidopsis plants. Similarly, GmMYB118-overexpressing (OE) soybean plants generated via Agrobacterium rhizogenes (A. rhizogenes)-mediated transformation of the hairy roots showed improved drought and salt tolerance. Furthermore, compared with the control (CK) plants, the clustered, regularly interspaced, short palindromic repeat (CRISPR)-transformed plants exhibited reduced drought and salt tolerance. The contents of proline and chlorophyll in the OE plants were significantly greater than those in the CK plants, whose contents were greater than those in the CRISPR plants under drought and salt stress conditions. In contrast, the reactive oxygen species (ROS) and malondialdehyde (MDA) contents were significantly lower in the OE plants than in the CK plants, whose contents were lower than those in the CRISPR plants under stress conditions.
These results indicated that GmMYB118 could improve tolerance to drought and salt stress by promoting expression of stress-associated genes and regulating osmotic and oxidizing substances to maintain cell homeostasis.
Lysine succinylation is a novel dynamic and evolutionarily conserved post-translational modification (PTM) that regulates various biological processes. 'Anji Baicha' is an albino tea variety that ...exhibits temperature-based variability of leaf colour and amino acid concentrations. However, the mechanism underlying albinism in 'Anji Baicha' has not been investigated at the level of succinylation. Here, we identify 3530 lysine succinylation sites mapped to 2132 proteins in 'Anji Baicha', representing the first extensive data on the lysine succinylome in the tea plant. Eleven conserved succinylation motifs were enriched among the identified succinylated peptides. The protein-protein interaction maps were visualized using Cytoscape software. Comparison across three typical developmental stages of 'Anji Baicha' revealed that proteins exhibiting differential succinylation levels were primarily involved in photosynthesis, carbon fixation, biosynthesis of amino acids and porphyrin and chlorophyll metabolism, suggesting that these succinylated proteins are involved in 'Anji Baicha' leaf colour variability. These results not only deepen our understanding of the mechanism underlying 'Anji Baicha' albinism and the regulatory role of succinylation in the tea plant but also provide new insight into molecular breeding for leaf colour variety.
Quercetin (QCT) has been shown to have anticancer activities associated with apoptosis and autophagy induction. However, whether autophagy is functionally responsible for the inhibitory effect of QCT ...on hepatocellular carcinoma (HCC) remains elusive. This study aims to investigate if QCT inhibits HCC growth via autophagy induction. The in vitro experiments showed that QCT inhibited the growth of human HCC cells in dose- and time-dependent manners and had minimal cytotoxicity to normal hepatocytes. QCT increased both autophagosomes and autolysosomes in HCC cells, as determined by electron microscopy, GFP-RFP-LC3 fluorescence confocal microscopy and Western blot analysis of autophagy-related biomarkers. Functional assays using pathway-specific inhibitors, activators or siRNAs indicated that QCT stimulated autophagy in part via inhibiting the AKT/mTOR pathway and activating the MAPK pathways. Further functional experiments using autophagy inhibitors demonstrated that QCT induced apoptosis of HCC cells in part via stimulating autophagy. The in vivo studies showed that QCT significantly inhibited tumor growth associated with apoptosis induction and autophagy stimulation, and that inhibition of autophagy significantly alleviated the QCT effect on tumor growth inhibition and apoptosis induction. To the best of our knowledge, this is the first in vivo report to demonstrate that QCT inhibits HCC tumor growth and induces apoptosis in part via stimulation of autophagy. Our results provide strong experimental evidence to support that autophagy stimulation may be an important mechanism by which QCT induces cancer cell apoptosis, and pave the way for further clinical investigations by applying QCT or QCT-rich foods for HCC intervention.
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Microplastic (MP) pollution has become an area of increasing concern because MPs accumulate various types of pollutants. Many previous studies have explored the interactions between MPs and ...hydrophobic pollutants. However, little research has been conducted on hydrophilic pollutants, which are of much higher concentration and ubiquitous in environment. Surfactants cause hydrophobic MPs to become hydrophilic, which may significantly enhance their capacities to adsorb hydrophilic pollutants. This study explored the influence of co-existing surfactants on the adsorption of ionic organic pollutants by MPs, and found that the presence of an ionic surfactant could significantly enhance the capacity of polyvinyl chloride (PVC, 0.2 mm) MPs to adsorb pollutants with opposite charges. The Langmuir methylene blue adsorption capacity of PVC could be increased from 172 to 4417 ppm in the presence of a sodium dodecyl benzene sulfonate surfactant. Nonionic surfactants impeded the adsorption of both cationic and anionic pollutants due to the steric resistance of the hydrophilic polyethelene glycol chains. The electrostatic interaction mechanism dominated the interfacial behaviors of ionic pollutants on surfactant-adsorbed MP interfaces. The effects of the surfactants were further verified using four different model pollutants and six surfactants. The adsorption capacities of real environmental MPs, including PVC, polyethylene (PE), polypropylene (PP), and polystyrene (PS), increased by three to twenty-six times. The adsorption properties of MPs may be determined by the presence of co-existing surfactants, rather than their polymer species or additives.
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•Surfactants possess strong influence on the vector effect of MPs.•Electrostatic force plays a key role in the adsorption of ionic pollutants.•Van der Waals’ force between surfactants and pollutants serves as an accomplice.•Nonionic surfactants impede the adsorption of both cationic and anionic pollutants.•Surfactant effect is verified in environmental microplastics.
The performance of nanomaterials in electrochemical energy conversion (fuel cells) and storage (secondary batteries) strongly depends on the nature of their surfaces. Designing the structure of ...electrode materials is the key approach to achieving better performance. Metal or metal oxide nanocrystals (NCs) with high-energy surfaces and open surface structures have attained significant attention in the past decade since such features possess intrinsically exceptional properties. However, they are thermodynamically metastable, resulting in a huge challenge in their shape-controlled synthesis. The tuning of material structure, design, and performance on the nanoscale for electrochemical energy conversion and storage has attracted extended attention over the past few years. In this Account, recent progress made in shape-controlled synthesis of nanomaterials with high-energy surfaces and open surface structures using both electrochemical methods and surfactant-based wet chemical route are reviewed. In fuel cells, the most important catalytic materials are Pt and Pd and their NCs with high-energy surfaces of convex or concave morphology. These exhibit remarkable activity toward electrooxidation of small organic molecules, such as formic acid, methanol, and ethanol and so on. In practical applications, the successful synthesis of Pt NCs with high-energy surfaces of small sizes (sub-10 nm) realized a superior high mass activity. The electrocatalytic performances have been further boosted by synergetic effects in bimetallic systems, either through surface decoration using foreign metal atoms or by alloying in which the high-index facet structure is preserved and the electronic structure of the NCs is altered. The intrinsic relationship of high electrocatalytic performance dependent on open structure and high-energy surface is also valid for (metal) oxide nanomaterials used in Li ion batteries (LIB). It is essential for the anode nanomaterials to have optimized structures to keep them more stable during the charge/discharge processes for reducing damaging volume expansion via intercalation and subsequent reduced battery lifetime. In the case of cathodes, tuning the surface structure of nanomaterials should be one of the most beneficial strategies to enhance the capacity and rate performance. In addition, metal oxides with unique defective structure of high catalytic activity and carbon materials of porous structure for facilitating fast Li+ diffusion paths and efficiently trapping polysulfide are most important approached and employed in Li–O2 battery and Li–S battery, respectively. In summary, significant progress has already been made in the electrocatalytic field, and likely emerging techniques based on NCs enclosed with high-energy surfaces and high-index facets could provide a promising platform to investigate the surface structure–catalytic functionality at nanoscale, thus shedding light on the rational design of practical catalysts with high activity, selectivity, and durability for energy conversion and storage.
Star performance: The shape and surface structure of star‐shaped gold nanoparticles (NPs) bounded by (331) and vicinal high‐index facets, now synthesized for the first time, can be tuned by varying ...the water content in the deep eutetic solvent. The results confirm that star‐shaped Au NPs exhibit superior activity for electrocatalytic reduction of H2O2. The ability to tune the shape offers insight into structure–functionality relationships.
Reports on bacteria detected in maternal fluids during pregnancy are typically associated with adverse consequences, and whether the female reproductive tract harbours distinct microbial communities ...beyond the vagina has been a matter of debate. Here we systematically sample the microbiota within the female reproductive tract in 110 women of reproductive age, and examine the nature of colonisation by 16S rRNA gene amplicon sequencing and cultivation. We find distinct microbial communities in cervical canal, uterus, fallopian tubes and peritoneal fluid, differing from that of the vagina. The results reflect a microbiota continuum along the female reproductive tract, indicative of a non-sterile environment. We also identify microbial taxa and potential functions that correlate with the menstrual cycle or are over-represented in subjects with adenomyosis or infertility due to endometriosis. The study provides insight into the nature of the vagino-uterine microbiome, and suggests that surveying the vaginal or cervical microbiota might be useful for detection of common diseases in the upper reproductive tract.Whether the female reproductive tract harbours distinct microbiomes beyond the vagina has been a matter of debate. Here, the authors show a subject-specific continuity in microbial communities at six sites along the female reproductive tract, indicative of a non-sterile environment.
Even at the best oxygen reduction reaction (ORR) catalyst, i.e., Pt-based materials, the ORR current is observed only below 1.0 VRHE, indicating an onset overpotential higher than 0.20 V (0.25 V at ...pure Pt). Rational design of more active ORR catalysts hinges on correct understanding of the origins of this high onset overpotential, which is a topic of controversy for decades. In this contribution, major viewpoints in the literature are recapitulated, a recent framework compiling several factors into a unified picture is introduced, and perspectives for more comprehensive analysis in future are given.
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•The origins for the high onset overpotential of ORR are discussed.•Major viewpoints in past five decades are reviewed.•Parasitic reactions lead to a mixed potential.•Kinetics and thermodynamics are intertwined.•“The blind men and the elephant” approach must be transcended.
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