Topological Defect-Regulated Porous Carbon Anodes with Fast Interfacial and Bulk Kinetics for High-Rate and High-Energy-Density Potassium-Ion Batteries.

Carbonaceous materials are regarded as one of the most promising anodes for potassium-ion batteries (PIBs), but their rate capabilities are largely limited by the slow solid-state potassium diffusion kinetics inside anode and sluggish interfacial potassium ion transfer process. Herein, high-rate and high-capacity PIBs are demonstrated by facile topological defect-regulation of the microstructure of carbon anodes. The carbon lattice of the as-obtained porous carbon nanosheets (CNSs) with abundant topological defects (TDPCNSs) holds relatively high potassium adsorption energy yet low potassium migration barrier, thereby enabling efficient storage and diffusion of potassium inside graphitic layers. Moreover, the topological defects can induce preferential decomposition of anions, leading to the formation of high potassium ion conductive solid electrolyte interphase (SEI) film with decreased potassium ion de-solvation and transfer barrier. Additionally, the dominant sp2-hybridized carbon conjugated skeleton of TDPCNSs enables high electrical conductivity (39.4 S cm-1) and relatively low potassium storage potential. As a result, the as-constructed TDPCNSs anode demonstrates high potassium storage capacity (504 mA h g-1 at 0.1 A g-1), remarkable rate capability (118 mA h g-1 at 40 A g-1), as well as long-term cycling stability.

A Thiol Branched 3D Network Quasi Solid-State Polymer Electrolyte Reinforced by Covalent Organic Frameworks for Lithium Metal Batteries.

Quasi solid-state polymer electrolytes (QSPEs) are particularly attractive due to their high ionic conductivity and excellent safety for lithium metal batteries (LMBs). However, it is still a great challenge for QSPEs to achieve strong mechanical strength and high electrochemical performance simultaneously. Herein, a QSPE (SCOF-PEP-PEA) using a covalent organic framework (COF) containing abundant allyl groups (SCOF) as a rigid porous filler as well as a cross-linker to reinforce the polymer network is reported. Benefitting from the unique 3D nanonetwork structure and abundant lithiophilic functional groups, SCOF-PEP-PEA QSPE exhibits high ionic conductivity (4.0 × 10-4 S cm-1) and high lithium-ion transference number (0.82) at room temperature. Moreover, SCOF-PEP-PEA QSPE displays much improved mechanical strength compared to PEP-PEA QSPE (AFM Young's modulus: 453 vs 36 MPa). As a result, the Li/LFP full cell with SCOF-PEP-PEA QSPE shows great rate performance of 141 mAh g-1 at 1C and delivers a high specific capacity retention of 92% after 220 cycles at 0.5 C (60 °C). This work provides a new strategy to design and prepare high-performance QSPEs with COFs as porous organic filler, and further expand the application of COFs for energy storage applications.

PVA/PAA/DMTD electrospun nanofibrous membrane for the selective adsorption of Pb(II) ions in liquid foods.

Lead (Pb(II)) contamination is common in liquid foods and can result from Pb(II) being present in the raw materials or during handling processes. However, due to the complexity of food matrices, there is limited data available concerning Pb(II) ion removal from food sources. This study focused on fabricating a PVA/PAA/DMTD electrospun nanofibrous membrane (ENFM) to efficiently and selectively remove Pb(II) ions from liquid foods. The PVA/PAA/DMTD ENFM had a maximum adsorption capacity of 138.3 mg/g for Pb(II) ions and demonstrated high selectivity toward the removal of Pb(II) ions. Negative values of the Gibbs free energy (ΔG°) showed that the spontaneous nature of the adsorption process was feasible at different temperatures. Moreover, it successfully removed Pb(II) ions from selected samples of commercially available drinks. Therefore, this adsorbent exhibits significant potential for removing Pb(II) ions from liquid food products, thereby reducing daily dietary exposure to Pb(II).

Covalent Organic Framework-based Solid-State Electrolytes, Electrode Materials, and Separators for Lithium-ion Batteries.

The increasing global energy consumption has led to the rapid development of renewable energy storage technologies. Lithium-ion batteries (LIBs) have been extensively studied and utilized for reliable, efficient, and sustainable energy storage. Nevertheless, designing new materials for LIB applications with high capacity and long-term stability is highly desired but remains a challenging task. Recently, covalent organic frameworks (COFs) have emerged as superior candidates for LIB applications due to their high porosity, well-defined pores, highly customizable structure, and tunable functionalities. These merits enable the preparation of tailored COFs with predesigned redox-active moieties and suitable porous channels that can improve the lithium-ion storage and transportation. This review summarizes the recent progress in the development of COFs and their composites for a variety of LIB applications, including (quasi) solid-state electrolytes, electrode materials, and separators. Finally, the challenges and potential future directions of employing COFs for LIBs are also briefly discussed, further promoting the foundation of this class of exciting materials for future advances in energy-related applications.

Serum homocysteine is a valuable marker for predicting aggravation of infection in intestinal obstruction patients.

The aim of this study was to investigate the expression of serum homocysteine (HCY), procalcitonin (PCT), and C-reactive protein (CRP) in abdominal infectious disease and analyze their relationship with the degree of abdominal infection. We conducted a retrospective study involving 157 patients with abdominal infections at Xuzhou Central Hospital between January 2016 and October 2019. The patients were composed of intestinal obstruction (73 cases), appendicitis (45 cases), perforation of the digestive tract (25 cases), and cholecystitis (14 cases). The HCY, PCT, and CRP levels of patients with abdominal infections were detected using enzyme-linked immunosorbent assay (ELISA), and correlation analysis between the HCY, PCT, and CRP levels and abdominal infection was performed using Pearson's correlation analysis. Compared with before treatment, the HCY, PCT, and CRP levels in the four groups decreased significantly after treatment. The levels in the patients in the intestinal obstruction group decreased more markedly than in those in the other groups. There were positive correlations among the HCY level, PCT, and CRP before treatment only in patients with intestinal obstruction (P < 0.001). The difference was statistically significant in the HCY level between the non-operation and the operation groups in patients with intestinal obstruction (P < 0.001). Serum HCY may be a valuable marker for predicting aggravation of infection in patients with intestinal obstruction.

Dendrite-Free and Long-Cycling Lithium Metal Battery Enabled by Ultrathin, 2D Shield-Defensive, and Single Lithium-Ion Conducting Polymeric Membrane.

Polymeric membranes are considered as promising materials to realize safe and long-life lithium metal batteries (LMBs). However, they are usually based on soft 1D linear polymers and thus cannot effectively inhibit piercing of lithium dendrites at high current density. Herein, single lithium-ion conducting molecular brushes (GO-g-PSSLi) are successfully designed and fabricated with a new 2D "soft-hard-soft" hierarchical structure by grafting hairy lithium polystyrenesulfonate (PSSLi) chains on both sides of graphene oxide (GO) sheets. The ultrathin GO-g-PSSLi membrane is further constructed by evaporation-induced layer-by-layer self-assembly of GO-g-PSSLi molecular brushes. Unlike conventional soft 1D linear polymeric structure, the rigid 2D extended aromatic structure of intralayer GO backbones can bear the shield effect of preventing the dendrites possibly generated at high current density from piercing. More importantly, such a shield effect can be significantly strengthened by layer-by-layer stacking of 2D molecular brushes. On the other hand, the 3D interconnected interlayer channels and the soft single lithium-ion conducting PSSLi side-chains on the surface of channels provide rapid lithium-ion transportation pathways and homogenize lithium-ion flux. As a result, LMBs with GO-g-PSSLi membrane possess long-term reversible lithium plating/striping (6 months) at high current density.

Fabrication strategies and biomedical applications of three-dimensional bacterial cellulose-based scaffolds: A review.

Bacterial cellulose (BC), an extracellular polysaccharide, is a versatile biopolymer due to its intrinsic physicochemical properties, broad-spectrum applications, and remarkable achievements in different fields, especially in the biomedical field. Presently, the focus of BC-related research is on the development of scaffolds containing other materials for in-vitro and in-vivo biomedical applications. To this end, prime research objectives concern the biocompatibility of BC and the development of three-dimensional (3D) BC-based scaffolds. This review summarizes the techniques used to develop 3D BC scaffolds and discusses their potential merits and limitations. In addition, we discuss the various biomedical applications of BC-based scaffolds for which the 3D BC matrix confers desired structural and conformational features. Overall, this review provides comprehensive coverage of the idea, requirements, synthetic strategies, and current and prospective applications of 3D BC scaffolds, and thus, should be useful for researchers working with polysaccharides, biopolymers, or composite materials.

Self-Supporting Electrocatalyst Film Based on Self-Assembly of Heterogeneous Bottlebrush and Polyoxometalate for Efficient Hydrogen Evolution Reaction.

Developing efficient electrocatalysts to promote the hydrogen evolution reaction (HER) is essential for a green and sustainable future energy supply. For practical applications, it is a challenge to achieve the self-assembly of electrocatalyst from microscopic to macroscopic scales. Herein, a facile strategy is proposed to fabricate a self-supporting electrocatalyst film (CNT-g-PSSCo/PW12 ) for HER by electrostatic interaction-induced self-assembly of cobalt polystyrene sulfonate-grafted carbon nanotube heterogeneous bottlebrush (CNT-g-PSSCo) and polyoxometalate (PW12 ). Co2+ ions of CNT-g-PSSCo can function as junctions for interconnecting neighboring bottlebrushes to form the 3D nanonetwork structure and enable electrostatic capture of negatively charged PW12 nanodots. Moreover, CNT backbones can provide highly conductive pathways to CNT-g-PSSCo/PW12 . Such a self-assembled CNT-g-PSSCo/PW12 displays a low overpotential of 31 mV at a current density of 10 mA cm-2 and a small Tafel slope of 25 mV dec-1 , showing high efficiency toward HER. Furthermore, CNT-g-PSSCo/PW12 with a stable self-supporting film morphology exhibits long-term electrocatalytic stability over 1000 CV cycles without noticeable overpotential change in acidic media. The findings may provide a new avenue for constructing self-assembled functional nanonetwork materials with well-orchestrated structural hierarchy for many applications in energy, environment, catalysis, medicine, and others.

Emerging porous organic polymers for biomedical applications.

Porous organic polymers (POPs) have emerged as a new class of multifunctional porous materials and received tremendous research attention from both academia and industry. Most POPs are constructed from versatile organic small molecules with diverse linkages through strong covalent bonds. Owing to their high surface area and porosity, low density, high stability, tunable pores and skeletons, and ease of functionalization, POPs have been extensively studied for gas storage and separation, heterogeneous catalysis, biomedicine, sensing, optoelectronics, energy storage and conversion, etc. Particularly, POPs are excellent platforms with exciting opportunities for biomedical applications. Consequently, considerable efforts have been devoted to preparing POPs with an emphasis on their biomedical applications. In this review, first, we briefly describe the different subclasses of POPs and their synthetic strategies and functionalization approaches. Then, we highlight the state-of-the-art progress in POPs for a variety of biomedical applications such as drug delivery, biomacromolecule immobilization, photodynamic and photothermal therapy, biosensing, bioimaging, antibacterial, bioseparation, etc. Finally, we provide our thoughts on the fundamental challenges and future directions of this emerging field.

CoS2 Nanoparticles Embedded in Covalent Organic Polymers as Efficient Electrocatalyst for Oxygen Evolution Reaction with Ultralow Overpotential.

Cobalt disulfide (CoS2 ) has been explored as attractive electrocatalyst for oxygen evolution reaction (OER). However, bulk CoS2 sheets have limited catalytic activity due to low exposure of active sites. Herein, through an in-situ vulcanization approach, CoS2 nanoparticles are embedded into bipyridine-containing covalent organic polymer (BP-COP). The as-prepared nanocomposite CoS2 @BP-COP exhibits high catalytic activity toward OER with an ultra-low overpotential of 270 mV (vs. RHE) at a current density of 10 mA cm-2 , a small Tafel slope of 36 mV dec-1 , and an excellent durability for 24 h without decay. The surface of CoS2 is partially converted into CoOOH to form CoS2 /CoOOH as active sites under OER conditions. CoS2 @BP-COP displays superior OER catalytic activity to CoS2 nanosheets and commercially available RuO2 under the same conditions. The outstanding OER performance activity of CoS2 @BP-COP could be attributed to the uniform and small particle sizes of CoS2 /CoOOH distributed in BP-COP.

Pillar[n]arene-based supramolecular organic frameworks with high hydrocarbon storage and selectivity.

We report the high hydrocarbon storage capacity and adsorption selectivity of two low-density pillar[n]arene-based SOFs. Our study would open new perspectives in the development of pillar[n]arene-based SOFs and study of their great potential in gas-storage and gas-separation applications.

CD133 mediates the TGF-ß1-induced activation of the PI3K/ERK/P70S6K signaling pathway in gastric cancer cells.

Cluster of differentiation (CD)133 has been reported to be involved in the activation of the extracellular signal-regulated kinase (ERK) signaling pathway in different types of cancer cells. CD133 has been reported to be involved in the activation of the ERK signaling pathway in various cancer cells. Transforming growth factor (TGF)-ß1 has also been reported to mediate the activation of the ERK signaling pathway. In addition, TGF-ß1 has been previously shown to mediate the activation of the ERK signaling pathway. Hence, the present study investigated the function of CD133 in the TGF-ß1-induced activation of the ERK/P70S6K signaling pathway in human gastric cancer (GC) cells. To this end, GC cell lines SGC7901 and MKN45 were treated with TGF-ß1. The expression of CD133, phospho-ERK (p-ERK) and phospho-P70S6 kinase (p-P70S6K) was upregulated in the cells treated with TGF-ß1, while the expression of ERK and P70S6K was not altered. To investigate whether CD133 is involved in the TGF-ß1-induced activation of the ERK/P70S6K signaling pathway in GC cells, immunomagnetic cell sorting was employed to isolate CD133+ GC cells, and a CD133-expression construct or CD133-targeting small interfering ribonucleic acids were transfected into cells to modulate the expression of CD133. Subsequently, the expression of CD133, ERK, p-ERK, P70S6K, and p-P70S6K was analyzed by western blotting. The CD133+ cells displayed a high expression of p-ERK and p-P70S6K. Furthermore, SGC7901 GC cells were treated with U0126, an inhibitor of the ERK signaling pathway, to assess whether CD133 is upstream of ERK/P70S6K. The results showed that the expression of p-ERK and p-P70S6K was downregulated in the cells treated with U0126, while the expression of CD133 remained unaltered. The above preliminary results showed that CD133 likely mediates the TGF-ß1-induced activation of the ERK/P70S6K signaling pathway in human GC cells. To further understand the mechanism of regulation of the ERK/P70S6K signaling pathway by CD133, the expression of CD133 was modulated by transfecting cells with CD133-expression constructs or CD133-targeting small interfering ribonucleic acids. Results indicated that overexpression and silencing of CD133 directly increased and decreased the expression of p-ERK and p-P70S6K, respectively. Therefore, we hypothesized that CD133 mediates the TGF-ß1-induced activation of the PI3K/ERK/P70S6K signaling pathway in human GC cells.

Desymmetrized Vertex Design for the Synthesis of Covalent Organic Frameworks with Periodically Heterogeneous Pore Structures.

Two novel porous 2D covalent organic frameworks (COFs) with periodically heterogeneous pore structures were successfully synthesized through desymmetrized vertex design strategy. Condensation of C(2v) symmetric 5-(4-formylphenyl)isophthalaldehyde or 5-((4-formylphenyl)ethylene)isophthalaldehyde with linear hydrazine linker under the solvothermal or microwave heating conditions yields crystalline 2D COFs, HP-COF-1 and HP-COF-2, with high specific surface areas and dual pore structures. PXRD patterns and computer modeling study, together with pore size distribution analysis confirm that each of the resulting COFs exhibits two distinctively different hexagonal pores. The structures were characterized by FT-IR, solid state (13)C NMR, gas adsorption, SEM, TEM, and theoretical simulations. Such rational design and synthetic strategy provide new possibilities for preparing highly ordered porous polymers with heterogeneous pore structures.

Metallated porphyrin based porous organic polymers as efficient electrocatalysts.

Developing efficient, stable and low-cost catalysts for Oxygen Reduction Reaction (ORR) is of great significance to many emerging technologies including fuel cells and metal-air batteries. Herein, we report the development of a cobalt(II) porphyrin based porous organic polymer (CoPOP) and its pyrolyzed derivatives as highly active ORR catalysts. The as-synthesized CoPOP exhibits high porosity and excellent catalytic performance stability, retaining ∼100% constant ORR current over 50,000 s in both alkaline and acidic media. Pyrolysis of CoPOP at various temperatures (600 °C, 800 °C, and 1000 °C) yields the materials consisting of graphitic carbon layers and cobalt nanoparticles, which show greatly enhanced catalytic activity compared to the as-synthesized CoPOP. Among them, CoPOP-800/C pyrolyzed at 800 °C shows the highest specific surface area and ORR activity, displaying the most positive half-wave potential (0.825 V vs. RHE) and the largest limited diffusion current density (5.35 mA cm(-2)) in an alkaline medium, which are comparable to those of commercial Pt/C (20 wt%) (half-wave potential 0.829 V vs. RHE, limited diffusion current density 5.10 mA cm(-2)). RDE and RRDE experiments indicate that CoPOP-800/C directly reduces molecular oxygen to water through a 4-e(-) pathway in both alkaline and acidic media. More importantly, CoPOP-800/C exhibits excellent durability and methanol-tolerance under acidic and alkaline conditions, which surpass the Pt/C (20 wt%) system.

Overexpression of CD133 enhances chemoresistance to 5-fluorouracil by activating the PI3K/Akt/p70S6K pathway in gastric cancer cells.

CD133 has been reported to be associated with chemoresistance in various cancer cells. The efficacy of 5-fluorouracil (5-FU), an important chemotherapeutic agent for advanced gastric cancer (GC), is limited by 5-FU resistance. Hence, the present study investigated the function of CD133 in 5-FU resistance in human GC cells. We isolated CD133+ GC cells by immunomagnetic cell sorting and CD133 expression was modulated by transfection of CD133 gene or CD133 small interfering ribonucleic acid. To assess the 5-FU cytotoxicity, Cell Counting Kit-8 was used. Expression of CD133, P-glycoprotein (P-gp), B-cell lymphoma 2 (Bcl­2), Bcl-2-associated X protein (Bax), phospho-Akt (p-Akt) and phospho-p70S6 kinase (p-p70S6K) were analyzed by western blotting. CD133, P-gp, Bcl-2 and Bax messenger ribonucleic acids were evaluated using semi-quantitative reverse transcriptase-polymerase chain reaction. Cell apoptosis was assessed by Hoechst 33258 staining. CD133+ cells were more resistant to 5-FU than CD133- cells, and showed higher expression of P-gp and Bcl-2 with lower expression of Bax. Furthermore, CD133 silencing enhanced 5-FU cytotoxicity and apoptotic characteristics, whereas CD133 overexpression increased 5-FU resistance. CD133 silencing and activation directly decreased and increased the expression of P-gp, Bcl­2, p-Akt and p-p70S6K, respectively. Notably, Akt inhibition by LY294002 restored the 5-FU cytotoxicity suppressed by CD133 overexpression, while Akt activation by epidermal growth factor reversed the 5-FU cytotoxicity enhanced by CD133 silencing. Therefore, CD133 may inhibit 5-FU-induced apoptosis by regulating the expression of P-gp and Bcl-2 family mediated by phosphoinositide 3-kinase/Akt/p70S6K pathway in GC cells.

Overexpression of FOXM1 is associated with EMT and is a predictor of poor prognosis in non-small cell lung cancer.

Forkhead box M1 (FOXM1), a member of the Fox family of transcriptional factors, is considered to be an independent predictor of poor survival in many solid cancers. However, the underlying mechanism is not yet clear. The aim of the present study was to investigate the clinical significance of the correlation between FOXM1 and epithelial-mesenchymal transition (EMT) in non-small cell lung carcinoma and the possible mechanism responsible for FOXM1-induced EMT and metastasis. In the present study, expression levels of FOXM1 and EMT indicator proteins were determined by tissue microarray (TMA) and immunohistochemical staining, western blotting and reverse transcription-PCR (RT-PCR). Other cellular and molecular approaches including gene transfection, small interfering RNA (siRNA), and migration and invasion assays were utilized. Our results demonstrated that FOXM1 overexpression was statistically significantly associated with a higher TNM stage (p=0.036), lymph node metastasis (p=0.009) and a positive smoking history of the patients (p=0.044). Additionally, high expression of FOXM1 correlated with loss of E-cadherin expression (p<0.001) and anomalous immunopositivity of Vimentin (p=0.002). Moreover, patient survival analysis demonstrated that high expression of FOXM1 (p=0.043) and the presence of lymph node metastasis (p=0.042) were independent prognostic factors for non-small cell lung cancer (NSCLC). Furthermore, various in vitro experiments indicated that overexpression or knockdown of FOXM1 expression altered EMT through activation or inhibition of the AKT/p70S6K signaling pathway. Collectively, the results suggest that FOXM1 may be used as a prognostic indicator for patients with NSCLC and promotes metastasis by inducing EMT of lung cancer cells through activation of the AKT/p70S6K pathway. Therefore, we suggest that FOXM1 may be a potential target for lung cancer therapy.

[Relationship between CD133 and chemoresistance in human gastric cancer and its associated mechanism].

OBJECTIVE: To explore the relationship between CD133(+) subsets cells in human gastric cancer (GC) and molecules of drug resistance and their sensitivity to 5-FU. METHODS: Three gastric cancer cell lines therein KATO-III(, SGC7901 and MKN45 were sorted by immunomagnetic beads cell sorting method. Then above cell lines were further divided into un-sorted GC cells, CD133(+) subgroup and CD133(-) subgroup. The expressions of CD133, P-gp, Bax and Bcl-2 were determined by RT-PCR, Western blot and immunoflurescence. Meanwhile, the sensitivity to 5-FU of three subgroups was detected by CCK-8 Kit. The apoptosis induced by 5-FU in three subgroups was determined by Hoechst 33258. RESULTS: Expressions of CD133 in three CD133(+) subgroups were significantly higher than those in un-sorted GC cells and CD133(-) subgroup (all P<0.05). Expressions of P-gp and Bcl-2 in the three GC cell lines were different (all P<0.05). There were significant differences of expressions of P-gp, Bcl-2 and Bax among CD133(+) cells, un-sorted GC cells and CD133(-) cells (all P<0.05). CCK-8 detection showed that CD133(-) subgroup of MKN45 GC cell line was more sensitive than CD133(+) cells to 5-FU (P<0.05). Hoechst 33258 staining showed that there were more apoptotic cells in CD133(-) subgroup as compared to other two subgroups, and the least apoptotic cells were observed in CD133(+) subgroup of MKN45 GC cell line (P<0.05). CD133 sirna was transfected into MKN45 GC cell line and could down-regulate the expressions of CD133, P-gp, Bcl-2 and p-Akt, while the expression of Bax increased (all P<0.05). CONCLUSIONS: CD133 may contribute to the resistance of GC cells to chemotherapy drug through P-gp, Bcl-2 and Bax. PI3K/Akt signal pathway may be involved in this process.

FOXM1 regulated by ERK pathway mediates TGF-ß1-induced EMT in NSCLC.

FOXM1, a member of the Forkhead transcriptional family, plays an important role in the EMT process, and transforming growth factor-ß1 (TGF-ß1) has been identified as the most potent factor that can independently induce EMT in various types of cancer cells. Here we examine the important role of FOXM1 in TGF-ß1-induced EMT and investigate the mechanism underlying the relationship between TGF-ß1 and FOXM1. Lentivirus-mediated transfection was used to stably upregulate the expression of FOXM1, and a small interfering RNA (siRNA) was introduced to silence the expression of FOXM1. Transwell and wound-healing assays were then performed to assess the invasion and motility potential of non-small cell lung cancer (NSCLC) cells. The NSCLC cell lines exhibited EMT characteristics, including an elongated fibroblastoid shape, induced expression of EMT marker proteins, and increased migratory and invasive potential after induction with TGF-ß1. The overexpression of FOXM1 enhanced TGF-ß1-induced EMT in NSCLC cells. Knockdown of FOXM1 reversed TGF-ß1-induced EMT in NSCLC cell lines but had no effect on the phosphorylation level of ERK. Additionally, U0126, an ERK signaling inhibitor, exerted a reversible effect on TGF-ß1-induced EMT and inhibited FOXM1 expression. FOXM1 regulated by the ERK pathway can mediate TGF-ß1-induced EMT in NSCLC and is a potential target for the treatment of NSCLC.