Search

An atomically dispersed structure is attractive for electrochemically converting carbon dioxide (CO2) to fuels and feedstock due to its unique properties and activity. Most single-atom electrocatalysts are reported to reduce CO2 to carbon monoxide (CO). Herein, we develop atomically dispersed indium (In) on a nitrogen-doped carbon skeleton (In-N-C) as an efficient catalyst to produce formic acid/formate in aqueous media, reaching a turnover frequency as high as 26771 h-1 at -0.99 V relative to a reversible hydrogen electrode (RHE). Electrochemical measurements show that trace amounts of In loaded on the carbon matrix significantly improve the electrocatalytic behavior for the CO2 reduction reaction, outperforming conventional metallic In catalysts. Further experiments and density functional theory (DFT) calculations reveal that the formation of intermediate *OCHO on isolated In sites plays a pivotal role in the efficiency of the CO2-to-formate process, which has a lower energy barrier than that on metallic In.

The role of intraoperative use of indocyanine green (ICG) fluorescence angiography (ICGFA) to prevent anastomotic leakage (AL) in rectal cancer surgery remains controversial. The systematic review for studies evaluating ICGFA in patients undergoing rectal cancer surgery in PubMed, Embase, Web of Science, and the Cochrane Library was performed up to April 30, 2020. The primary outcome was the incidence of AL. The analysis was performed using RevMan v5.3 and Stata v12.0 software. Eighteen studies comprising 4038 patients were included. In the present meta-analysis, intraoperative use of ICGFA markedly reduced AL rate (OR = 0.33; 95% CI: 0.24–0.45; P

Changes in histone H3 lysine 9 trimethylation (H3K9me3) may be related to the development of drug-resistant acute myeloid leukaemia (AML); insights into the network of H3K9me3 may improve patient prognosis. Patient data were derived from the Gene Expression Omnibus (GEO) database and data from AML cells treated with chidamide, a novel benzamide chemical class of histone deacetylase inhibitor (HDACi), in vitro were derived from ChIP-seq. Patients and AML cell data were analysed using GEO2R, GOseq, KOBAS, the STRING database and Cytoscape 3.5.1. We identified several genes related to the upregulation or downregulation of H3K9me3 in AML patients; some of these genes were related to apoptosis, autophagy, and the pathway of cell longevity. AML cells treated with chidamide in vitro showed the same gene changes. The protein interactions in the network did not have significantly more interactions than expected, suggesting the need for more research to identify these interactions. One compelling result from the protein interaction study was that sirtuin 1 (SIRT1) may have an indirect interaction with lysine-specific demethylase 4A (KDM4A). These results help explain alterations of H3K9me3 in AML that may direct further studies aimed at improving patient prognosis. These results may also provide a basis for chidamide as a treatment strategy for AML patients in the future.

BACKGROUND Intestinal inflammation is a common digestive tract disease, which is usually treated with hormone medicines. Hormone medicines are effective to some extent, but long-term use of them may bring about many complications. AIM To explore the protective effects of panax notoginseng saponin (PNS) against dextran sulfate sodium (DSS)-induced intestinal inflammatory injury through phosphoinositide-3-kinase protein kinase B (PI3K/AKT) signaling pathway inhibition in rats. METHODS Colitis rat models were generated via DSS induction, and rats were divided into control (no modeling), DSS, DSS + PNS 50 mg/k, and DSS + PNS 100 mg/kg groups. Then, the intestinal injury, oxidative stress parameters, inflammatory indices, tight junction proteins, apoptosis, macrophage polarization, and TLR4/AKT signaling pathway in colon tissues from rats in each of the groups were detected. The PI3K/AKT signaling pathway in the colon tissue of rats was blocked using the PI3K/AKT signaling pathway inhibitor, LY294002. RESULTS Compared with rats in the control group, rats in the DSS group showed significantly shortened colon lengths, and significantly increased disease activity indices, oxidative stress reactions and inflammatory indices, as well as significantly decreased expression of tight junction-associated proteins. In addition, the DSS group showed significantly increased apoptotic cell numbers, and showed significantly increased M1 macrophages in spleen and colon tissues. They also showed significantly decreased M2 macrophages in colon tissues, as well as activation of the PI3K/AKT signaling pathway (all P < 0.05). Compared with rats in the DSS group, rats in the DSS + PNS group showed significantly lengthened colon lengths, decreased disease activity indices, and significantly alleviated oxidative stress reactions and inflammatory responses. In addition, this group showed significantly increased expression of tight junction-associated proteins, significantly decreased apoptotic cell numbers, and significantly decreased M1 macrophages in spleen and colon tissues. This group further showed significantly increased M2 macrophages in colon tissues, and significantly suppressed activation of the PI3K/AKT signaling pathway, as well as a dose dependency (all P < 0.05). When the PI3K/AKT signaling pathway was inhibited, the apoptosis rate of colon tissue cells in the DSS + LY294002 group was significantly lower than that of the DSS group (P < 0.05). CONCLUSION PNS can protect rats against DSS-induced intestinal inflammatory injury by inhibiting the PI3K/AKT signaling pathway, and therefore may be potentially used in the future as a drug for colitis.

Photoreduction of CO2 to fuels offers a promising strategy for managing the global carbon balance using renewable solar energy. But the decisive process of oriented photogenerated electron delivery presents a considerable challenge. Here, we report the construction of intermolecular cascaded pi-conjugation channels for powering CO2 photoreduction by modifying both intramolecular and intermolecular conjugation of conjugated polymers (CPs). This coordination of dual conjugation is firstly proved by theoretical calculations and transient spectroscopies, showcasing alkynyl-removed CPs blocking the delocalization of electrons and in turn delivering the localized electrons through the intermolecular cascaded channels to active sites. Therefore, the optimized CPs (N-CP-D) exhibiting CO evolution activity of 2247 mu mol g(-1) h(-1) and revealing a remarkable enhancement of 138-times compared to unmodified CPs (N-CP-A). While conversion of CO2 to fuels may offer a bio-inspired means to renewably utilize fossil fuel emission, most materials demonstrate poor activities for CO2 reduction. Here, authors construct conjugated polymers that modulate photo-induced electron transfer to CO2 reduction catalysts.

The rhizome of P. japonicus var. major, one of the important herbs in Traditional Chinese medicine (TCM), has been used as tonic and hemostatic drugs in Tujia and Miao ethnic groups of China for thousand years. In this study, comparative metabolite and transcriptome analysis of rhizome nodes and internodes of wild P. japonicus var. major was performed to reveal their different roles in the biosynthesis of triterpene saponins. The results showed that the node was the crucial section for the synthesis of ginsenosides in the rhizome. The content of oleanane-type ginsenosides in the node was much higher than those in the internode. Most isoprenoid biosynthesis-related genes were highly expressed in the node. And, candidate UDP-glycosyltransferase (UGT) genes were also found to be differentially expressed between node and internode. Our study will provide a better understanding of the metabolism of ginsenosides in the rhizome of P. japonicus var. major.

Background Chondrocyte apoptosis activated by the mitochondrial dependent pathway serves a crucial role in cartilage degeneration of osteoarthritis (OA). In the present study, the protective effects of CMCS against sodium nitroprusside (SNP)-induced chondrocyte apoptosis were evaluated and the underlying molecular mechanisms were elucidated. Methods Chondrocytes were isolated from articular cartilage of SD rats and identified by type II collagen immunohistochemistry. The chondrocytes stimulated with or without SNP to induce apoptosis, were treated by CMCS for various concentrations. The cell viability were determined by MTT and LDH assays. Cell apoptotic ratio was determined by Annexin V-FITC/PI staining. Mitochondrial membrane potential (ΔΨm) was detected by using Rhodamine123 (Rho123) staining. To understand the mechanism, the mRNA expression levels of Bcl-2, Bax, cytochrome c (Cyt c) and cleaved caspase-3 were detected by real-time PCR and western blot analysis, respectively. Results It was shown using the MTT and LDH assays that CMCS protected the viability of chondrocyte against SNP damage. Annexin V-FITC/PI and Rho123 staining showed that CMCS not only inhibited the cell apoptosis but also restored the reduction of the ΔΨm in chondrocytes. In SNP-induced chondrocytes, CMCS down-regulated the expression of Bax, Cyt c and cleaved caspase-3 but upregulated the expression of Bcl-2, as shown by real-time PCR and western blot. Conclusions Taken together, these results indicated that CMCS has the protective effect on chondrocytes against SNP-induced apoptosis, at least partly, via inhibiting the mitochondrial dependent apoptotic pathway. Thus, CMCS may be potentially used as a biological agent for prevention and treatment of OA.

The particulate backscattering coefficient (bbp) provides effective proxies for particulate organic carbon (POC) and phytoplankton carbon (Cphy); however, their bio-optical relationships in the oligotrophic ocean are rarely reported. In this work, based on the in-situ synchronous optical and biogeochemical measurements in the oligotrophic South China Sea (SCS) basin, we refined the regional relationships between POC (and Cphy) and bbp and investigated the impacts of phytoplankton community compositions and size classes on the bbp variability. The observations showed that: 1) POC and Cphy exhibited good linear relationships with bbp; 2) the relationship between Cphy and POC could also be fitted in a linear function with a positive POC intercept, and the POC contributed by phytoplankton-covarying non-algal particles was nearly two-fold of Cphy; and 3) the POC-specific bbp (b*bp) was positively correlated with the fraction of the phytoplankton groups haptophytes (Type 8) and diatoms to total Chla, but negatively correlated with the fraction of pico-phytoplankton to Chla (fpico). These findings suggest that in oligotrophic waters, the variability of b*bp was mainly determined by the variability in the relative contribution of large phytoplankton with complex structures.

The aim of this study was to investigate the potential biological activities of nutlin-3 in the regulation of growth and proliferation of non-small cell lung cancer (NSCLC) stem cells (CSCs), which may help in sensitizing to axitinib-induced apoptosis. Nutlin-3 induction of p53 expression was used to test its role in controlling the cell division pattern and apoptosis of NSCLC cells. A549 cells and H460 cells were pretreated with nutlin-3 and then treated with either an Akt1 activator or shRNA-GSK3β, to investigate the potential role of p53 sensitization in the biological effects of axitinib. We also determined the expression levels of GSK3β and p-Akt1 in patients with NSCLC and determined their potential association with survival data using Kaplan‐Meier plots and CBIOTAL. Increased p53 expression stimulated the induction of apoptosis by axitinib and promoted asymmetric cell division (ACD) of NSCLC CSCs. The repression of Akt phosphorylation induced by nutlin-3 promoted the ACD of lung CSCs, decreasing the proportion of the stem cell population. In addition to the induction of apoptosis by axitinib through inhibition of Wnt signaling, nutlin-3 treatment further enhanced axitinib-induced apoptosis by inhibiting Akt1/GSK3β/Wnt signaling. The low expression of GSK3β and increased expression of p-Akt in patients with NSCLC were closely associated with the development of NSCLC. TP53 stimulates the induction of apoptosis in NSCLC by axitinib and the ACD of lung CSCs through its regulatory effects on the p53/Akt/GSK3β pathways.

Exposing and stabilizing undercoordinated platinum (Pt) sites and therefore optimizing their adsorption to reactive intermediates offers a desirable strategy to develop highly efficient Pt-based electrocatalysts. However, preparation of atomically controllable Pt-based model catalysts to understand the correlation between electronic structure, adsorption energy, and catalytic properties of atomic Pt sites is still challenging. Herein we report the atomically thin two-dimensional PtTe2 nanosheets with well-dispersed single atomic Te vacancies (Te-SAVs) and atomically well-defined undercoordinated Pt sites as a model electrocatalyst. A controlled thermal treatment drives the migration of the Te-SAVs to form thermodynamically stabilized, ordered Te-SAV clusters, which decreases both the density of states of undercoordinated Pt sites around the Fermi level and the interacting orbital volume of Pt sites. As a result, the binding strength of atomically defined Pt active sites to H intermediates is effectively reduced, which renders PtTe2 nanosheets highly active and stable in hydrogen evolution reaction., Precisely regulating Pt catalytic sites is important and challenging. Herein the authors engineer the clustering of single atomic Te vacancies in atomically thin PtTe2 to optimize the electronic structure, adsorption energy, and catalytic performance of atomically defined Pt sites.

Single-atom catalysts (SACs) represent a new frontier in heterogeneous catalysis due to their remarkable catalytic properties and maximized atomic utilization. However, single atoms often bond to the support with polarized electron density and thus exhibit a high valence state, limiting their catalytic scopes in many chemical transformations. Here, we demonstrated that two-dimensional (2D) black phosphorus (BP) act as giant phosphorus (P) ligand to confine a high density of single atoms (eg, Pd1, Pt1) via atomic layer deposition. Unlike other 2D materials, BP with relatively low electronegativity and buckled structure favors the strong confinement of robust zero-valent palladium SACs in the vacancy site. Metallic Pd1/P SAC shows a highly selective semi-hydrogenation of phenylacetylene towards styrene, outperforming high-valence Pt1/P SAC, and also distinct from metallic Pd nanoparticles that facilitate the formation of fully hydrogenated products. Our DFT calculations reveal that Pd atom forms covalent-like bonding with adjacent P atoms, wherein H atoms tend to adsorb over electron-rich region for the subsequent hydrogenation. Zero-valent Pd in the confined space favors a larger energy gain for the synthesis of partially-hydrogenated product over the fully-hydrogenated one. Our work provides a new route towards the synthesis of zero-valent SACs on BP for a wide range of organic transformations.

Background Aberrant microRNA (miRNAs) have recently been proposed as important regulators in acquiring resistance to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) in diffuse large B-cell lymphoma (DLBCL). The purpose of this study was to establish the role of miR-148b in the development of CHOP resistance in DLBCL. Methods The expression patterns of miR-148b, HDAC6, and Ezrin were detected in CHOP-resistant clinical specimens and a DLBCL cell line. miR-148b, HDAC6, and Ezrin in DLBCL cells were manipulated by cell transfection to explore the functional correlation between them. Cell viability was determined using a CCK-8 assay. Results We found that miR-148b levels were markedly reduced and that the protein expressions of HDAC6 and Ezrin were increased in DLBCL CHOP-resistant clinical specimens and the cell line CRL2631/CHOP. Indeed, HDAC6 decreased the acetylation of histones H3 and H4 in the miR-148b promoter to inhibit miR-148b expression in DLBCL. Moreover, down-regulated miR-148b encouraged CHOP resistance in CRL2631 cells and miR-148b sensitized CRL2631 cells. We further revealed that Ezrin was negatively regulated by miR-148b and that the knockdown of Ezrin significantly attenuated CHOP resistance in CRL2631 cells induced by miR-148b silencing. MiR-148b also sensitized CRL2631/CHOP cell xenografts to CHOP in mice. Conclusion Our data indicated that the high level of HDAC6 inhibited miR-148b via maintaining the low acetylation of histones H3 and H4 in the miR-148b promoter, thus rescuing Ezrin expression and promoting CHOP resistance in DLBCL.

Recently, molybdenum sulfide with its amorphous counterpart was found to hold a high activity versus the hydrogen evolution reaction (HER), making it a high potential material to explore new HER catalysts. Here we present a facile chemical method to synthesize ultra-small freestanding amorphous molybdenum sulfide (a-MoSx) colloidal nanodots with diameter of lower than 2 nm. Electrocatalytic HER tests show that freestanding a-MoSx colloidal nanodots exhibit an enhanced catalytic hydrogen activity in stark in contrast with in-situ annealed c-MoS2. When applied as a co-catalyst in photocatalytic HER, ultra-small a-MoSx nanodots could form a compact interface with the TiO2 when assisted by a bifunctional molecular linker, as the mercaptopropionic acid (MPA), which facilitates the decrease of the interfacial Schottky barrier occurring between the two components and allows for a fast injection of photo-excited electrons from the photoharvester into the co-catalyst. Our results demonstrate that the drastic enhancement of the photocatalytic H2 promotion rate of a-MoSx@MPA-TiO2 is mainly provided by unsaturated Mo(IV) active sites generated by the in-situ reduction during the photocatalytic HER process. The synergistic effect of generated unsaturated Mo(IV) sites and the presence of more exposed intrinsic active edges further promotes the enhancement of the catalytic H2 activity on a-MoSx nanodots.

BACKGROUND Ulcerative colitis (UC) is a main form of inflammatory bowel disease. Due to complicated etiology and a high rate of recurrence, it is quite essential to elucidate the underlying mechanism of and search for effective therapeutic methods for UC. AIM To investigate the effects of astragalus polysaccharides (APS) combined with matrine on UC and associated lung injury. METHODS UC was induced in rats by colon mucosal tissue sensitization combined with trinitro-benzene-sulfonic acid-ethanol. Then, the effects of the treatments of salazopyrine, APS, matrine, and APS combined with matrine on histopathological changes of lung and colon tissues, disease activity index (DAI), colon mucosal damage index (CMDI), serum endotoxin (ET) level, serum diamine oxidase (DAO) activity, the contents of tumor necrosis factor-α and interleukin-1β, and the activities of myeloperoxidase, superoxide dismutase, and malondialdehyde in lung tissues, as well as the protein expression of zonula occludens (ZO)-1, Occludin, and trefoil factor 3 (TFF3) were detected in UC rats. RESULTS The treatments of salazopyrine, APS, matrine, and APS combined with matrine reduced DAI scores and improved histopathological changes of colon and lung tissues, as well as decreased CMDI scores, ET levels, and DAO activities in UC rats. Moreover, in lung tissues, inflammatory response and oxidative stress injury were relieved after the treatments of salazopyrine, APS, matrine, and APS combined with matrine in UC rats. Furthermore, the expression of ZO-1, Occludin, and TFF3 in lung and colon tissues was increased after different treatments in UC rats. Notably, APS combined with matrine exerted a better protective effect against UC and lung injury compared with other treatments. CONCLUSION APS combined with matrine exert a synergistic protective effect against UC and lung injury, which might be associated with regulating TFF3 expression.

Molybdenum disulfide (MoS 2 ) presents a promising nonprecious catalyst for hydrogen evolution reaction (HER) that has attracted extensive interest, but it still lacks an effective way to advance the utilization, in particular the basal plane of freestanding 2H-MoS 2 for HER. Herein, we report a rational design of freestanding 2H-MoS 2 monolayers to maximize the synergistic activity for HER by combining crystallinity engineering and cobalt substitution. Electrochemical measurements and density functional theory calculations indicate that the combination of crystallinity engineering and cobalt substitution in monolayer 2H-MoS 2 can not only introduce massive defects that act as new active sites but also activate and make use of the basal plane, which is responsible for the much enhanced HER activity compared to independent crystallinity engineering or cobalt substitution. Impressively, when integrated with a photoharvester cadmium sulfide for photocatalytic hydrogen evolution, the synergistic effect also promotes an excellent cocatalytic performance of monolayer 2H-MoS 2 that even higher than platinum (Pt). This study potentially provide new avenues for designing more efficient MoS 2 -based and other layered materials with enhanced HER performance.

Two lanthanide MOFs, namely {{Me2NH2}[TbIII(L)]·3H2O·DMF}n (1) and {{Me2NH2}[EuIII(L)]·3H2O·DMF}n (2), based on the flexible ligand 5-(bis(4-carboxybenzyl)amino)isophthalic acid (H4L) have been synthesized under solvothermal conditions, where DMF = N,N-dimethylformamide. The two compounds exhibit a 3D structure with rectangle channels encapsulating [Me2NH2]+ cations. The microporous structure as well as the confinement of cations inside the MOFs pores allows 1 and 2 to act as dual-functional luminescent materials to detect nitroaromatics and metal ions. The experiments show that the luminescence of sample 1 in DMF solution was quenched when the nitrobenzene (NB) content reached 2.3 × 10−2 mol/L and concentration of Fe3+ reached 5 × 10−4 mol/L.

As a promising non-precious catalyst for the hydrogen evolution reaction (HER), molybdenum disulfide (MoS2), which is known to contain highly active edge sites and an inert basal plane, has attracted extensive interest. More recently, its amorphous counterpart has been found to have a higher HER activity, making it important to explore the effect of crystallinity on the HER performance of monolayer MoS2. However, the posed technological challenges of preparing crystallinity tunable 2H–MoS2 monolayers hinder their further study. In this work, we report the successful synthesis of crystallinity-dependent MoS2 monolayers through liquid exfoliation of the corresponding crystallinity-controllable bulk precursors. Excellent cocatalytic performances of the proposed MoS2 monolayers for the photocatalytic HER were achieved and determined by their crystallinity. An apparent quantum efficiency as high as 71.6% can be achieved for the lowest crystalline monolayer MoS2 over cadmium sulfide under visible light irradiation at 420 nm. This work provides a facile way to synthesise crystallinity controllable MoS2 monolayers and elucidates that the HER activity can be further enhanced through crystallinity engineering, providing a new strategy to enhance the HER activity of monolayer MoS2.

In this study, we describe the genome sequence of a novel double-stranded RNA (dsRNA) mycovirus, designated as “Rhizoctonia solani partitivirus 15” (RsPV15), from the phytopathogenic fungus Rhizoctonia solani. RsPV15 consists of two genomic double-stranded RNA segments, dsRNA-1 and dsRNA-2, which are 2433 bp and 2350 bp long, respectively. Each of the dsRNA segments contains a single open reading frame, encoding the putative RNA-dependent RNA polymerase and coat protein, respectively. Homology searches and phylogenetic analysis suggested that RsPV15 is a new member of the genus Betapartitivirus within the family Partitiviridae.

Osteosarcoma is a highly malignant and aggressive bone tumor. Its occurrence and development involve many factors and multiple signaling pathways. Some studies have shown that circular RNAs (circRNAs) play important roles in the development of various tumors. This research showed that circ_ORC2 was generally up-regulated in various osteosarcoma cell lines, and mainly distributed in the cytoplasm. Circ_ORC2 had the binding site of miR-19a, and its expression was positively correlated with miR-19a expression. RIP experiments showed that circ_ORC2 could bind to Ago2 protein. RNA pull-down using biotinylated circ_ORC2 or miR-19a showed that circ_ORC2 could directly interact with miR-19a, and dual luciferase reporter gene assay also confirmed that miR-19a could bind to circ_ORC2. After circ_ORC2 knockdown, miR-19a expression was down-regulated, but the downstream target gene PTEN expression was up-regulated, and the phosphorylation level of Akt was reduced, which indicated that circ_ORC2 enhanced the inhibition of miR-19a on PTEN expression by combining miR-19a. Further functional experiments showed that after circ_ORC2 knockdown, cell proliferation and invasion decreased, while the apoptosis level increased. When co-transfected with circ_ORC2 siRNA and miR-19a mimics or PTEN siRNA, the above cell biological behaviors did not change significantly. Therefore, circ_ORC2 binds with miR-19a and enhances its expression, thereby inhibiting downstream PTEN expression and activating Akt pathway to promote osteosarcoma cell growth and invasion. These findings enrich the circRNA molecular regulation mechanism, and provide more reference ideas for the research and application of circRNAs in tumors and other diseases.

Reactions of cadmium ions with the flexible tetracarboxylic ligand, 5-(bis(4-carboxybenzyl)amino) isophthalic acid (H4L) gave rise to four complexes, namely {[(Me2NH2)2Cd3(L)2]∙10H2O)}n (1), {[Cd2(L)(pdp)(H2O)2]∙2DMF·4H2O}n (pdp = 4-[(E)-4-Pyridinylazo]pyridine) (2), {[Cd2(L)(bpe)(H2O)2]∙2DMF·4H2O}n (bpe = 1,2-bi(4-pyridyl)ethene) (3) and {[Cd4(L)2(bpmp)3]∙2H2O}n (bpmp = N,Nʹ-bis-(4-pyridyl-methyl) piperazine) (4). Compound 1 features a three-dimensional anionic architecture constructed by triangular Cd3 cluster and ligands, with rectangle channels encapsulating [Me2NH2]+ cations. Compounds 2 and 3 present similar structures, exhibiting the 2D polythreading layer. Compound 4 possesses a 3D structure with 4,6-connected new topology. The powder X-ray diffraction, the thermal stabilities, and solid-state luminescence properties were studied for 1–4. Furthermore, the luminescent sensing of compounds 1 and 4 toward nitrobenzene has also been investigated.

Through a facile and effective strategy by employing lithium molten salts the controlled synthesis of 2H- and 1T-MoS2 monolayers with high-yield production is achieved. Both phases of MoS2 monolayers exhibit high stabilities. When used as a catalyst for hydrogen evolution, these phased MoS2 monolayers deliver respective advantages in the field of electro- and photo-catalytic hydrogen evolution.

A simple method is developed to fabricate protonated porous graphitic carbon nitride nanosheets (P-PCNNS) by protonation-exfoliation of bulk graphitic carbon nitride (BCN) with phosphoric acid (H3 PO4 ). The H3 PO4 treatment not only helps to exfoliate the BCN into 2D ultrathin nanosheets with abundant micro- and mesopores, endowing P-PCNNS with more exposed active catalytic sites and cross-plane diffusion channels to facilitate the mass and charge transport, but also induces the protonation of carbon nitride polymer, leading to the moderate removal of the impurities of carbon species in BCN for the optimization of the aromatic π-conjugated system for better charge separation without changing its chemical structure. As a result, the P-PCNNS show much higher photocatalytic performance for hydrogen evolution and CO2 conversion than bare BCN and graphitic carbon nitride nanosheets.

Au-based catalysts were widely applied in photocatalytic areas owing to Au local surface plasmon resonance (LSPR), especially in the reactions of secondary alcohol dehydrogenation. However, there were rare cases reporting Au catalysts to dehydrogenate secondary alcohols under dark condition at room temperature. In this work, basic semiconductor birnessite, with easily extractable lattice oxygen in its lattice structure, was employed as support of Au catalyst and it was found that the Au/birnessite catalyst could dehydrogenate iso-propanol (IPA) to acetone under dark condition (3.7 μmol acetone was produced within 5 h). With the utilization of lattice oxygen in the reaction under dark condition, oxygen vacancies were instantaneously formed which enhanced the light absorbing properties of Au/birnessite and further improved its photocatalytic activity (13.6 μmol acetone production within 5 h). The synergistic effects between lattice oxygen and oxygen vacancies enhanced the performance of Au-based catalyst in IPA dehydrogenation and this work provides a synthesis tactic for effective catalysts in the dehydrogenation of various secondary alcohols.

A facile synthesis of high performance flexible V2O5-based cathodes constructed by V2O5 nanosheets encapsulated within multi-graphene nanotubes and the successful demonstration of a flexible full cell.

Background: Angiogenesis is the formation of new blood vessels to supply nutrients to tumors. Vascular endothelial growth factor (VEGF) and cluster of differentiation 34 (CD34) are important signaling proteins involved in angiogenesis. Many studies have demonstrated that VEGF and CD34 are related to tumor progression. This study focused on the relationship between VEGF, CD34, and perioperative hemorrhage in patients with gastric cancer. Methods: To observe the relationship between VEGF and CD34, we tracked 112 patients with advanced gastric cancer for 5 years to assess factors related to hemorrhage, using immunohistochemistry. The results were subjected to statistical analysis using a 2 × 2 contingency table, logistic regression, and receiver operating characteristic (ROC) test. Results: The concentrations of VEGF and CD34 were critically correlated with perioperative hemorrhage and neural invasion in patients with gastric cancer (P < 0.05). Expression of VEGF and CD34 was related (P < 0.05, χ2 = 6.834). VEGF and CD34 co-expression strongly increased the risk of preoperative bleeding (area under the ROC curve >0.7, P < 0.05). Conclusions: Expression of VEGF and CD34 was critically correlated with perioperative hemorrhage in gastric cancer patients. Co-expression of VEGF and CD34 could be an effective indicator for evaluating the risk of perioperative bleeding in gastric cancer patients.

The stability of nanomaterials in aquatic environment is a critical factor that governs their fate and ecotoxicity. Meanwhile, the interaction between nanomaterials and ubiquitous natural organic matter (NOM) is a vital process that influences the transport and biological effects of nanomaterials in the environment. However, impacts of NOM on the aggregation and transport of two-dimensional nanomaterials, especially for the increasingly used graphene oxide (GO), are not well understood. Particularly, there is lack of exploration on potential impacts of the heterogeneous properties of NOM on GO behaviour, especially that induced by the wide molecular weight (MW) span of NOM. In this study, effects of several kinds of well-characterized MW fractionated Suwannee River NOM (Mf-SRNOMs) on the aggregation and transport of GO in aqueous media and saturated porous media were investigated. Our results suggest that the stability and migration capacity of GO under most investigated electrolyte conditions are promoted by all Mf-SRNOMs, and efficiencies of different Mf-SRNOMs are generally positively correlated with their MW. Primarily, mechanisms including MW-dependent steric hindrance and sorption of Mf-SRNOMs onto GO are critical in stabilizing GO, and thus facilitating its transport. However, the stronger sorption of higher Mf-SRNOMs onto the GO basal plane through π-π interaction further facilitated the cation bridging between both ends of Mf-SRNOM and GO, and resulted in heteroaggregation of NOM-GO. Moreover, the weight analysis indicated that despite the fact that high Mf-SRNOMs only occupied a small percentage of pristine-SRNOM, they showed a stronger contribution towards pristine-SRNOM's capacity in stabilizing GO, when compared with that of lower MW counterpart. These findings pointed out that complex effects of the heterogeneities of NOM and cations should be highly relevant when the aggregation and transport behaviour of two-dimensional nanomaterials is investigated, and NOM fractions that are highly aromatic and of a higher MW should receive greater attention.

Multiple myeloma (MM), the second most common hematologic malignancy, is an incurable disease characterized by the accumulation of malignant plasma cells within the bone marrow. Though great progresses have been made in understanding the mechanisms of MM, metabolic plasticity and drug resistance remain largely unknown. In this study, we found lncRNA Protein disulfide isomerase family A member 3 pseudogene 1 (PDIA3P) is highly expressed in MM and is associated with the survival rate of MM patients. PDIA3P regulates MM growth and drug resistance through Glucose 6-phosphate dehydrogenase (G6PD) and the pentose phosphate pathway (PPP). Mechanistically, we revealed that PDIA3P interacts with c-Myc to enhance its transactivation activity and binding to G6PD promoter, stimulating G6PD expression and PPP flux. Our study identified PDIA3P as a novel c-Myc interacting lncRNA and elucidated crucial roles for PDIA3P in metabolic regulation of MM, providing a potential therapeutic target for MM patients.

Carboxymethylated chitosan (CMCS) has many beneficial effects, including anti-oxidant and anti-apoptotic actions. However, the mechanisms by which CMCS protect against oxidative stress induced damage to Schwann cells (SCs) remains unclear. The present study aimed to investigate the mechanism by which CMCS protects SCs against hydrogen peroxide (H2O2) induced damage. H2O2 was used to establish a model of oxidative stress injury in SCs to mimic the development of nerve injury in vitro. Different concentrations (50, 100 and 200 µg/ml) of CMCS were added to test whether CMCS was capable of protecting SCs from H2O2 induced damage. MTT, LDH release and Annexin V/FITC assays were then performed. Levels of reactive oxygen species were detected using a reactive oxygen species assay kit, the mitochondrial membrane potential (ΔΨm) of SCs was analyzed by rhodamine123 fluorescence staining, the synthesis of Bcl-2, Bax, cytochrome c and caspase-3 were analyzed by real-time PCR and Western blot analysis. The results showed that CMCS protected SCs from apoptosis, decreased LDH release and enhanced cell viability, also decreased reactive oxygen species levels and increased ΔΨm. Additional experiments demonstrated that CMCS could decrease protein expression of Bax, cytochrome c and caspase-3, while promote Bcl-2 protein expression induced by H2O2. Taken together, the finding of this study indicated that CMCS prevented H2O2-induced damage to SCs through the mitochondrial dependent pathway.

In this work, an inorganic multifunctional nanovehicle was tailored as a carrier to deliver anticancer drug for tumor optical imaging and therapy. The nanovehicle could be used as a dually targeted drug nanovehicle by bonded magnetical (passive) and folic acid (active) targeting capabilities. In addition, it was developed using rhodamine 6G (R6G) as a fluorescence reagent, and an α-zirconium phosphate nanoplatform (Zr(HPO4)2·H2O, abbreviated as α-ZrP) as the anticancer drug nanovehicle. The novel drug-release system was designed and fabricated by intercalation of α-ZrP with magnetic Fe3O4 nanoparticles and anticancer drug 5-fluorouracil (5-FU), followed by reacting with a folate acid-chitosan-rhodamine6G (FA-CHI-R6G) complex, and then α-ZrP intercalated with Fe3O4 nanoparticles and 5-fluorouracil (5-FU) was successfully encapsulated into chitosan (CHI). The resultant multifunctional drug delivery system was characterized by scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray analysis, photoluminescence spectra, magnetometry, fluorescence microscopy imaging studies and other characterization methods. Simultaneously, the drug release in vitro on the obtained nanocomposites that exhibited a sustained release behavior was carried out in buffer solution at 37 °C, which demonstrated clearly that the nanocomposites shown a sustained release behavior. Meanwhile, cell culture experiments also indicated that the drug-release system had the potential to be used as an dually targeted drug nanovehicle into the tumor cells.

A homochiral three-dimensional framework material, [Cu(7)(4-bpt)(6)(CN)(H(2)O)] (1) (4-bpt = 3,5-bis(4-pyridyl)-1,2,4-triazole), has been successfully synthesized by solvothermal reaction, which is generated through an unusual spontaneous asymmetrical crystallization from achiral precursors, and its photocatalytic properties in degradation of organic dyes are also investigated.

Urban trees have the potential to reduce air pollution, but the retention capacity and efficiency of different tree species for atmospheric particulate matter (PM) accumulation and the underlying mechanism hasn't been well understood. To select tree species with high air purification abilities, the supplementing ultrasonic cleaning (UC) procedure was first introduced into the conventional leaf cleaning methods [single water cleaning (WC) or plus brush cleaning (BC)] for eluting the leaf-retained PM. Further updates to the methodology were applied to investigate the retention capacity, efficiency, and mechanism for PM of five typical greening tree species in Beijing, China. Meanwhile, the particle size distribution of PM on the leaves, the PM retention efficiencies of easily removable (ERP), difficult-to-remove (DRP) and totally removable (TRP) particles on the leaf (AEleaf), and the individual tree scales were estimated. The experimental leaf samples were collected from trees with similar sizes 4 (SDR) and 14days (LDR) after rainfall. When the leaves were cleaned by WC+BC, there was, on average, 29%-46% of the PM remaining on the leaves of different species, which could be removed almost completely if UC was supplemented. From SDR to LDR, the mass of the leaf-retained PM increased greatly, and the particle size distribution changed markedly for all species except for Sophorajaponica. Pinus tabuliformis retains particles with the largest average diameter (34.2μm), followed by Ginkgo biloba (20.5μm), Sabina chinensis (16.4μm), Salix babylonica (16.0μm), and S. japonica (13.1μm). S. japonica and S. chinensis had the highest AEleaf to retain the TRP and ERP of both PM1 and PM1-2.5, respectively. Conversely, S. babylonica and P. tabuliformis could retain both TRP and ERP of PM2.5-5 and PM5-10, and PM>10 and TSP with the highest AEleaf, respectively. In conclusion, our results could be useful in selecting greening tree species with high air purification abilities.

A highly enantioselective supramolecular iminium-catalyzed vinylogous Michael addition/Stetter relay sequence has been developed. This transformation provided a series of Hajos-Wiechert-type fused bicyclic diones with three continuous stereogenic centers in good yields with excellent enantioselectivities. The obtained products can be easily transformed into other structures with potential synthetic value.

Helical monosubstituted polyacetylene@CdSe quantum dots (HPA@CdSe QDs) nanocomposites were fabricated by grafting helical HPA polymers onto the surface of semiconductor QDs through ester linkage. Optically active HPA derived from chiral serine was polymerized by a rhodium zwitterion catalyst, and evidently proved to adopt a predominately single-handed helical conformation. The HPA@QDs nanocomposites were characterized by Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). The results indicate that the HPA matrix exhibits an enhancement in thermal stability after hybridization with CdSe QDs, while the QDs can maintain their original crystalline structure during the grafting process. The infrared emissivity property of the HPA@QDs nanocomposites at 8-14 μm was further investigated. These data demonstrated that the HPA@QDs composite film with doped CdSe QDs possesses an infrared emissivity value of 0.393, which was much lower than pristine HPA and QDs. This might be attributed to the incorporation of optically active helical HPA and semiconductor QDs in a hybrid phase and their strengthened interfacial interaction.

Hierarchically structured LDHs are being actively investigated due to their potential applications in bioseparation and catalysis which result from their special surface structures and positively charged nanosheets. This work presents an effective method of fabricating hierarchical LDHs based materials with high surface-to-volume ratios. To do this, the microscaled Al2O3 fibers are fabricated via a simple biotemplate method employing paper fibers as templates and in the second step the nanoscaled Ni-Al LDH platelets are fabricated into hierarchical architectures based on crystal growth on surface of Al2O3 fibers. In order to obtain the multi-component and multi-scale structure LDHs based materials, the ZnO/LDHs composites are obtained by controlling crystal growth process. The developed facile route is highly valuable and feasible for hierarchical porous LDHs based materials for applications in research and industrial fields.

An advanced multifunctional, hollow metal-organic framework (MOF) drug delivery system with a high drug loading level and targeted delivery was designed and fabricated for the first time and applied to inhibit tumour cell growth. This hollow MOF targeting drug delivery system was prepared via a simple post-synthetic surface modification procedure, starting from hollow ZIF-8 successfully obtained for the first time via a mild phase transformation under solvothermal conditions. As a result, the hollow ZIF-8 exhibits a higher loading capacity for the model anticancer drug 5-fluorouracil (5-FU). Subsequently, 5-FU-loaded ZIF-8 was encapsulated into polymer layers (FA-CHI-5-FAM) with three components: a chitosan (CHI) backbone, the imaging agent 5-carboxyfluorescein (5-FAM), and the targeting reagent folic acid (FA). Thus, an advanced drug delivery system, ZIF-8/5-FU@FA-CHI-5-FAM, was fabricated. A cell imaging assay demonstrated that ZIF-8/5-FU@FA-CHI-5-FAM could target and be taken up by MGC-803 cells. Furthermore, the as-prepared ZIF-8/5-FU@FA-CHI-5-FAM exhibited stronger cell growth inhibitory effects on MGC-803 cells because of the release of 5-FU, as confirmed by a cell viability assay. In addition, a drug release experiment in vitro indicated that ZIF-8/5-FU@FA-CHI-5-FAM exhibited high loading capacity (51%) and a sustained drug release behaviour. Therefore, ZIF-8/5-FU@FA-CHI-5-FAM could provide targeted drug transportation, imaging tracking and localized sustained release.

The global distributions of the air-seaCO(2) transfer velocity and flux are retrieved from TOPEX/Poseidon and Jason altimeter data from October 1992 to December 2009 using a combined algorithm. The 17 a average global, area-weighted, Schmidt number-corrected mean gas transfer velocity is 21.26 cm/h, and the full exploration of the uncertainty of this estimate awaits further data. The average total CO2 flux (calculated by carbon) from atmosphere to ocean during the 17 a was 2.58 Pg/a. The highest transfer velocity is in the circumpolar current area, because of constant high wind speeds and currents there. This results in strongCO(2) fluxes. CO2 fluxes are strong but opposite direction in the equatorial east Pacific Ocean, because the air-sea CO2 partial pressure difference is the largest in the global oceans. The results differ from the previous studies calculated using the wind speed. It is demonstrated that the air-sea transfer velocity is very important for estimating air-sea CO2 flux. It is critical to have an accurate estimation for improving calculation of CO2 flux within climate change studies.

Three new complexes, {[Mn(dtb)(bpe)·2H2O]·H2O} n (1), {[Mn(dtb)(bpa)·2H2O]·H2O} n (2), and {[Mn(dtb)(phen)]} n (3) [H2dtb = 5,5′-dithiobis(2-nitrobenzoic acid), bpe = 1,2-bis(4-pyridyl)ethene, bpa = 1,2-bi(4-pyridyl)ethane, phen = 1,10-phenanthroline], have been synthesized under hydrothermal conditions with Mn(OAc)2·4H2O, dtb, and different N-donor ligands. X-ray structure analyses of 1 and 2 reveal analogous structures with 1D helical chains and 2D 44 chiral layers. The structure of 3 shows a 1D chain which is outwardly decorated with phen ligands. These neutral polymeric complexes exhibit structural diversity due to the different coordination modes of the flexible dtb ligand and the N-donor ligands. The thermogravimetric analyses and X-ray powder diffractions of 1–3 are also presented.

Herein, S1P1 partial agonists with shorter half-life than our previous clinical candidate are reported. The pulmonary and cardiac safety are assessed, issues currently observed with commercial Gilenya.

An overall PEC CO2 conversion was firstly reported by integrating both the newly designed metal cathode and the n-type photoanode with functional nanostructures. The maximum Faradaic efficiency (FE) for CO is ca. 75% at -1.2 V with incident photon-to-current conversion efficiency (IPCE) value of 16% at 340 nm.

A new coordination polymer, {[Ag(H3bptc)(bpe)] · 2H2O} n (1) (H4bptc = 3,3′,4,4′-benzophenonetetracarboxylic acid, bpe = 1,2-bis(4-pyridyl)ethene), has been synthesized through a hydrothermal technique and structurally characterized. The crystal structure of 1 exhibits a 2-D hydrogen-bonding sheet between H3bptc− and two free water molecules. Fluorescent property, TG analysis, and X-ray powder diffraction for 1 were also measured and discussed.

Stress-induced hippocampal volume loss and decrease in N-acetylaspartate (NAA) level have been reported to be associated with impaired neural plasticity and neuronal damage in adults. Accordingly, reversing structural and metabolite damage in the hippocampus may be a desirable goal for antidepressant therapy. The present study investigated the effects of tianeptine on chronic stress-induced hippocampal volume loss and metabolite alterations in vivo in 24 Sprague-Dawley rats. Rats were subjected to a consecutive 28-day forced swimming test stress. Tianeptine (50mg/kg) or saline was administered intragastrically 4h after swimming each day. Spontaneous behaviors, serum corticosterone concentration, hippocampal volume and NAA level were evaluated after stress. Chronic tianeptine treatment counteracted the chronic stress-induced suppression of spontaneous behaviors, elevated serum corticosterone concentration, reduced hippocampal volume and decreased NAA level. Moreover, we found asymmetrical right-left hippocampal volume loss in stressed rats, with the left hippocampus more sensitive to chronic stress than the right hippocampus. In addition, stressed rats showed a decreased level of hippocampal metabolites, without significant loss of hippocampal volume. These findings provide experimental evidence for impaired structural plasticity of the brain being an important feature of depressive illness and suggest that prophylactic tianeptine treatments could reverse structural changes in brain. The structural and neurochemical alterations in the hippocampus may be valuable indexes for evaluating the prophylactic and curative effect of antidepressant treatments in depressive and stress-related disorders.