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We report that the use of a hydrogen-bonded pyrimidine-macrocycle complex can efficiently facilitate the threading of two bispyridinium ethylenes into four rings, as evidenced by X-ray crystallography of its precursor, offering a rare example of a doubly threaded [6]rotaxane in 91% yield. The unusual architecture is found to be stable with no dethreading despite the large ring size of the macrocycle with respect to the stopper.

Both covered self-expandable metal stents (CSEMSs) and uncovered self-expandable metal stents (USEMSs) have been tried in the palliation of malignant distal biliary strictures by means of endoscopic retrograde cholangiopancreatography (ERCP); however, the comparison of efficacy and safety between them remains contested. To the best of our knowledge, no similar studies have assessed this in the Chinese population. In the present study, the clinical and endoscopic data of 238 patients (CSEMSs, n=55; USEMSs, n=183) with malignant distal biliary strictures from 2014 to 2019 were collected. The efficacy indicated by mean stent patency, stent patency rate, mean patient survival time and survival rate, and the safety indicated by adverse events after CSEMS or USEMS placement were retrospectively analyzed and compared. The mean stent patency time was significantly longer in the CSEMSs group than that in the USEMSs group (262.8±195.3 days vs. 169.5±155.7 days, P=0.002). The mean patient survival time was significantly longer in the CSEMSs group than that in the USEMSs group (273.9±197.6 days vs. 184.9±167.6 days, P=0.003). The stent patency rate and patient survival rate were significantly higher in the CSEMSs group than those in the USEMSs group at 6 and 12 months, but not at 1 and 3 months. There was no significant difference in stent dysfunction and adverse events between the two groups, although post-ERCP pancreatitis (PEP) occurred more frequently in the CSEMSs group than in the USEMSs group (18.1% vs. 8.8%, P=0.049). In conclusion, CSEMSs were better than USEMSs for malignant distal biliary strictures in terms of stent patency time and patient survival time as well as stent patency rate and patient survival rate in the long term (>6 months). Adverse events in the two groups occurred at a similar rate, although the incidence of PEP was higher in the CSEMSs group., Competing Interests: The authors declare that they have no competing interests., (Copyright: © Zhu et al.)

Use of abiotic chemical systems for understanding higher order superstructures is challenging. Here we report a ring-in-ring(s) system comprising a hydrogen-bonded macrocycle and cyclobis(paraquat-o-phenylene) tetracation (o-Box) or cyclobis(paraquat-p-phenylene) tetracation (CBPQT 4+ , p-Box) that assembles to construct discrete higher order structures with adaptive conformation. As indicated by mass spectrometry, computational modeling, NMR spectroscopy, and single-crystal X-ray diffraction analysis, this ring-in-ring(s) system features the box-directed aggregation of multiple macrocycles, leading to generation of several stable species such as H4G (1 a/o-Box) and H5G (1 a/o-Box). Remarkably, a dimeric shish-kebab-like ring-in-rings superstructure H7G2 (1 a/o-Box) or H8G2 (1 a/p-Box) is formed from the coaxial stacking of two ring-in-rings units. The formation of such unique dimeric superstructures is attributed to the large π-surface of this 2D planar macrocycle and the conformational variation of both host and guest., (© 2023 Wiley-VCH GmbH.)

Meningeal carcinomatosis (MC) is reported to occur in 4%-15% of patients with solid tumors. MC is not commonly associated with gastric carcinoma and is extremely rare in patients with early gastric cancer (EGC). MC derived from EGC after curative endoscopic submucosal dissection (ESD) has not been reported before. We present a rare case of a 49-year-old patient who developed MC after curative ESD of EGC. The cancer was an ulcerated lesion approximately 1.0 cm in diameter in endoscopic appearance in the minor curvature of the gastric antrum. The pathological examination after ESD indicated high-grade intraepithelial neoplasia (1.3 × 2.1 cm in size) with localized moderately differentiated adenocarcinoma (0-IIc in tumor stage, intestinal type in Lauren classification), which was confined to the mucosal layer with an intact submucosal layer and muscularis propria. The lesion was removed entirely by curative dissection without vertical and horizontal resection margins involvement in pathology. Two months after ESD, the patient was readmitted for severe headache and vomiting. Cytological examination of the cerebrospinal fluid found malignant tumor cells, which were considered by pathologists to have metastasized from the stomach, further confirming MC derived from EGC. The patient's condition deteriorated dramatically, which prevented him from receiving further therapies, such as chemotherapy, and he died 3 days after the diagnosis of MC. In conclusion, EGC can cause MC, even after curative ESD. New neurological manifestations in patients with EGC can alert physicians to a diagnosis of MC, and more attention needs to be paid to evaluating the nervous system and establishing diagnostic and therapeutic strategies as soon as possible., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

The xylene is an important hydrophobic volatile organic compound (VOC) widely used as a solvent in different industries. Compared to the conventional bioreactors, the membrane bioreactor is more efficient for the degradation of hydrophobic VOCs. In this work, the degradation of gaseous xylene in a flat composite membrane bioreactor inoculated with activated sludge under different operating conditions was investigated. The maximum elimination capacities, EC v of 289 g/(m 3  h) and EC m of 0.145 g/(m 2  h) were obtained at the gas residence time of 20 s and the loading rate of 475 g/(m 3  h). Moreover, the membrane bioreactor is stable enough to suffer weak shock loading and short intermittent process shutdown. These results indicate that the membrane biotechnology shows great potentials in practical applications for xylene removal.

The efficient treatment of high stability emulsion with small diameter and the prevention of oil contamination of materials are serious issues in the process of emulsion separation. In order to address those issues, we reported a fast and versatile hydrophilic surface coating technology that uses oxidants and diamines to synergistically promote the polymerization of caffeic acid (CA). It was found that amino groups can not only accelerate the polymerization of CA, but also promote the deposition of polymers on the sponge surface. Using silica nanoparticles to improve the roughness, superhydrophilic melamine sponge could be prepared, which exhibited excellent superhydrophlic-underwater superolephobic and anti-oil-adhesion properties. DFT simulation was employed to explore the potential mechanism of the anti-oil adhesion ability. In addition, combined with the mechanical compression strategy, the sponge exhibited a high efficiency of 99.10% with a permeation flux of 19080 ± 700 Lm -2 h - 1 in emulsion separation just under the action of gravity. Moreover, based on the interaction between the surfactant and the surface of the material, the separation mechanism was discussed. Overall, this work provided an advanced method for the preparation of superhydrophilic sponge with anti-oil-fouling performance, which showed great potential in dealing with practically challenging emulsified wastewater., (Copyright © 2020. Published by Elsevier B.V.)

Objective To investigate the effect of oxidative stress preconditioning on the oxidative stress-induced damage of bone marrow mesenchymal stem cells (BMSCs). Methods BMSCs were isolated and cultured by density gradient centrifugation combined with adherence method. The cells were divided into three groups: control group (control medium), oxidative damage group (treated with 1000 μmol/L H 2 O 2 for 24 hours), and preconditioning group (preincubated with 50 μmol/L H 2 O 2 for 8 hours before treatment with 1000 μmol/L H 2 O 2 for 24 hours). DCFH-DA staining was used to analyze the level of reactive oxygen species (ROS). Mitochondrial membrane potential was measured by JC-1 staining. DNA damage was detected by TUNEL. Malondialdehyde (MDA) content was detected by thiobarbituric acid (TBA) method, and superoxide dismutase (SOD) activity was detected by water soluble tetrazolium-1 (WST-1) assay. CCK-8 assay was used to detect cell viability and flow cytometry to detect cell apoptosis. Results Compared with the oxidative damage group, the preconditioning group had reduced ROS level, reduced DNA damage, higher mitochondrial membrane potential, significantly decreased MDA content, increased SOD activity, increased cell viability, and significantly decreased apoptosis. Conclusion Oxidative stress preconditioning can enhance the anti-oxidative stress ability of BMSCs and promote its survival under oxidative stress.

Oxidative stresss in the microenvironment surrounding lesions induces apoptosis of transplanted bone-marrow-derived mesenchymal stem cells (BMSCs). Hence, there is an urgent need for improving antioxidative-stress processes of transplanted BMSCs to further promote their survival. The present study reports the role and mechanism of Parkinson's disease protein 7 (PARK7) in enhancing antioxidative activity in BMSCs. We used a PARK7 lentivirus to transfect BMSCs to up- or downregulate PARK7, and then used H 2 O 2 to simulate oxidative stress in BMSCs in vitro. Overexpression of PARK7 effectively reduced reactive oxygen species and malondialdehyde, protected mitochondrial membrane potential, and resisted oxidative-stress-induced apoptosis of BMSCs, but the expression of PARK7 was downregulated, these results were reversed. At the same time, we also found that overexpression of PARK7 increased extracellular-regulated protein kinase 1/2 (ERK1/2) phosphorylation and nuclear translocation, as well as upregulated Elk1 phosphorylation and superoxide dismutase (SOD) expression. In contrast, when U0126 was used to block the ERK1/2 pathway, ERK1/2 and Elk1 phosphorylation levels were downregulated, ERK1/2 nuclear translocation and SOD content were significantly reduced, and PARK7-overexperssion-induced antioxidative activity was completely blocked. Collectively, our results suggest that PARK7 overexpression increased antioxidative-stress processes and survival of BMSCs subjected to H 2 O 2 via activating the ERK1/2 signaling pathway. Our findings may guide the development of a PARK7-specific strategy for improving the transplantation efficacy of BMSCs., (© 2020 The Authors. Journal of Cellular Biochemistry Published by Wiley Periodicals LLC.)

Objective: To investigate the effects of low-concentration hydrogen peroxide pretreatment on the anti-oxidative stress of the bone marrow mesenchymal stem cells (BMSCs)., Methods: Rabbit BMSCs were isolated and cultured by density gradient centrifugation combined with the adherence method. Then, the third generation of well-grown BMSCs was continuously treated with 50-μM hydrogen peroxide (H 2 O 2 ) for 8 h as the optimal pretreatment concentration and the BMSCs were continuously applied for 24 h with 500 μM H 2 O 2 , and the optimal damage concentration was determined as the oxidative stress cell model. The experiment was divided into three groups: control group, high-concentration H 2 O 2 injury group (500 μM), and low-concentration H 2 O 2 pretreatment group (50 μM + 500 μM). In each group, the DCFH-DA fluorescence probe was used to detect the reactive oxygen species (ROS). ELISA was used to detect the activity of superoxide dismutase (SOD) and catalase (CAT), and the TBA method was used to detect malondialdehyde (MDA). The mitochondrial membrane potential was detected by JC-1. The cell viability was detected by CCK-8 method, while flow cytometry and TUNEL/DAPI double staining were performed to detect cell apoptosis. Hence, the effect of H 2 O 2 pretreatment on the anti-oxidative stress of BMSCs was investigated. One-way analysis of variance was performed using SPSS 19.0 statistical software, and P < 0.05 was considered statistically significant., Results: A large number of typical BMSCs were obtained by density gradient centrifugation and adherent culture. The oxidative stress cell model was successfully established by 500-μM H 2 O 2 . Compared with the high-concentration H 2 O 2 injury group, the low-concentration H 2 O 2 pretreatment reduced the production of ROS [(62.33 ± 5.05), P < 0.05], SOD and CAT activities significantly increased (P < 0.05), and MDA levels significantly decreased (P < 0.05). The mitochondrial membrane potential fluorescence changes, the ratio of red/green fluorescence intensity of the high-concentration H 2 O 2 injury group was less, and the ratio of the low-concentration H 2 O 2 pretreatment group was significantly higher than that. The ratio of red/green increased by about 1.8 times (P < 0.05). The cell viability and survival rate of BMSCs were significantly increased in low-concentration H 2 O 2 pretreatment group (P < 0.05), and the cell apoptosis rate was significantly decreased (P < 0.05)., Conclusion: Pretreatment with low-concentration H 2 O 2 can enhance the anti-oxidative stress ability and reduce their apoptosis of BMSCs under oxidative stress.

Objective: To investigate the effect of nicotinamide mononucleotide adenosyl transferase 3 (NMNAT3) on the mitochondrial function and anti-oxidative stress of rabbit bone marrow mesenchymal stem cells (BMSCs) under oxidative stress in vitro by regulating nicotinamide adenine dinucleotide (NAD + ) levels., Methods: The bone marrow of femur and tibia of New Zealand white rabbits were extracted. BMSCs were isolated and cultured in vitro by density gradient centrifugation combined with adherent culture. The third generation cells were identified by flow cytometry and multi-directional induction. Overexpression of NMNAT3 gene was transfected into rabbit BMSCs by enhanced green fluorescent protein (EGFP) labeled lentivirus (BMSCs/Lv-NMNAT3-EGFP), and then the expression of NMNAT3 was detected by real-time fluorescence quantitative PCR (qRT-PCR) and Western blot and cell proliferation by cell counting kit 8 (CCK-8) method. BMSCs transfected with negative lentivirus (BMSCs/Lv-EGFP) and untransfected BMSCs were used as controls. The oxidative stress injury cell model was established by using H 2 O 2 to treat rabbit BMSCs. According to the experimental treatment conditions, they were divided into 4 groups: Group A was normal BMSCs without H 2 O 2 treatment; untransfected BMSCs, BMSCs/Lv-EGFP, and BMSCs/Lv-NMNAT3-EGFP in groups B, C, and D were treated with H 2 O 2 simulated oxidative stress, respectively. The effects of NMNAT3 on the mitochondrial function of BMSCs under oxidative stress [changes of mitochondrial membrane potential, NAD + and adenosine triphosphate (ATP) levels], the changes of anti-oxidative stress ability of BMSCs [reactive oxygen species (ROS) and malondialdehyde (MDA) levels, manganese superoxide dismutase (Mn-SOD) and catalase (CAT) activities], and the effects of BMSCs on senescence and apoptosis [senescence associated-β-galactosidase (SA-β-gal) staining and TUNEL staining] were detected after 24 hours of treatment., Results: The rabbit BMSCs were successfully isolated and cultured in vitro . The stable strain of rabbit BMSCs with high expression of NMNAT3 gene was successfully obtained by lentiviral transfection, and the expressions of NMNAT3 gene and protein significantly increased ( P <0.05). There was no significant difference in the trend of cell proliferation compared with normal BMSCs. After treatment with H 2 O 2 , the function of mitochondria was damaged and apoptosis increased in all groups. However, compared with groups B and C, the group D showed that the mitochondrial function of BMSCs improved, the membrane potential increased, the level of NAD + and ATP synthesis of mitochondria increased; the anti-oxidative stress ability of BMSCs enhanced, the levels of ROS and MDA decreased, and the activities of antioxidant enzymes (Mn-SOD, CAT) increased; and the proportion of SA-β-gal positive cells and the rate of apoptosis decreased. The differences in all indicators between group D and groups B and C were significant ( P <0.05)., Conclusion: NMNAT3 can effectively improve the mitochondrial function of rabbit BMSCs via increasing the NAD + levels, and enhance its anti-oxidative stress and improve the survival of BMSCs under oxidative stress conditions.

In order to achieve the purpose of simultaneous removal of coexisting heavy metal ions, in this work, functionalized magnetic mesoprous nanomaterials (Fe 3 O 4 -HBPA-ASA) with high density and multiple adsorption sites were designed and prepared. The obtained Fe 3 O 4 -HBPA-ASA was characterized by SEM, FTIR, VSM, TGA and zeta potential. Cu(II), Pb(II) and Cd(II) were chosen as the model heavy metal ions, the adsorption experiments showed that Fe 3 O 4 -HBPA-ASA showed hightheoretical adsorption capacitiesin individual system, and the maximum adsorption capacity was 136.66 mg/g, 88.36 mg/g and 165.46 mg/g, respectively. In the binary and ternary systems, the competitive adsorption leads to a decrease in the adsorption capacity of Cu(II), Pb(II) and Cd(II). However, in the ternary system with a concentration lower than 15 mg/L, the simultaneous removal rate was still higher than 90%. The adsorption isotherms and kineticswere well fitted by Langmuir and pseudo-second-order models, respectively. The XPS and density functional theory (DFT) analysis have confirmed that the adsorption of metal ions was related to various types of functional groups on the surface of Fe 3 O 4 -HBPA-ASA, while the adsorption mechanisms of Cu(II), Cd(II) and Pb(II) were different., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Clinically, bone marrow mesenchymal stem cells (BMSCs) have been used in treatment of many diseases, but the local oxidative stress (OS) of lesion severely limits the survival of BMSCs, which reduces the efficacy of BMSCs transplantation. Therefore, enhancing the anti-OS stress ability of BMSCs is a key breakthrough point. Preconditioning is a common protective mechanism for cells or body. Here, the aim of this study was to investigate the effects of OS preconditioning on the anti-OS ability of BMSCs and its mechanism. Fortunately, OS preconditioning can increase the expression of superoxide dismutase, catalase, NQO1, and heme oxygenase 1 through the nuclear factor erythroid 2-related factor 2 pathway, thereby decreased the intracellular reactive oxygen species (ROS) levels, relieved the damage of ROS to mitochondria, DNA and cell membrane, enhanced the anti-OS ability of BMSCs, and promoted the survival of BMSCs under OS., (© 2019 The Authors. Journal of Cellular Biochemistry Published by Wiley Periodicals, Inc.)

In this work, electrically and thermally actuated triple shape memory polymers (SMPs) of chemically cross-linked polycyclooctene (PCO)-multiwalled carbon nanotube (MWCNT)/polyethylene (PE) nanocomposites with co-continuous structure and selective distribution of fillers in PCO phase are prepared. We systematically studied not only the microstructure including morphology and fillers' selective distribution in one phase of the PCO/PE blends, but also the macroscopic properties including thermal, mechanical, and electrical properties. The co-continuous window of the immiscible PCO/PE blends is found to be the volume fraction of PCO (vPCO) of ca. 40-70 vol %. The selective distribution of fillers in one phase of co-continuous blends is obtained by a masterbatch technique. The prepared triple SMP materials show pronounced triple shape memory effects (SMEs) on the dynamic mechanical thermal analysis (DMTA) and the visual observation by both thermal and electric actuations. Such polyolefin samples with well-defined microstructure, electrical actuation, and triple SMEs might have potential applications as, for example, multiple autochoke elements for engines, self-adjusting orthodontic wires, and ophthalmic devices.

Community detection in social networks attracts a lot of attention in the recent years. Existing methods always depict the relationship of two nodes using the temporary connection. However, these temporary connections cannot be fully recognized as the real relationships when the history connections among nodes are considered. For example, a casual visit in Facebook cannot be seen as an establishment of friendship. Hence, our question is the following: how to cluster the real friends in mobile social networks? In this paper, we study the problem of detecting the stable community core in mobile social networks. The cumulative stable contact is proposed to depict the relationship among nodes. The whole process is divided into timestamps. Nodes and their connections can be added or removed at each timestamp, and historical contacts are considered when detecting the community core. Also, community cores can be tracked through the incremental computing, which can help to recognize the evolving of community structure. Empirical studies on real-world social networks demonstrate that our proposed method can effectively detect stable community cores in mobile social networks.

In this paper, the triple shape memory effects (SMEs) observed in chemically cross-linked polyethylene (PE)/polypropylene (PP) blends with cocontinuous architecture are systematically investigated. The cocontinuous window of typical immiscible PE/PP blends is the volume fraction of PE (v(PE)) of ca. 30-70 vol %. This architecture can be stabilized by chemical cross-linking. Different initiators, 2,5-dimethyl-2,5-di(tert-butylperoxy)-hexane (DHBP), dicumylperoxide (DCP) coupled with divinylbenzene (DVB) (DCP-DVB), and their mixture (DHBP/DCP-DVB), are used for the cross-linking. According to the differential scanning calorimetry (DSC) measurements and gel fraction calculations, DHBP produces the best cross-linking and DCP-DVB the worst, and the mixture, DHBP/DCP-DVB, is in between. The chemical cross-linking causes lower melting temperature (Tm) and smaller melting enthalpy (ΔHm). The prepared triple shape memory polymers (SMPs) by cocontinuous immiscible PE/PP blends with v(PE) of 50 vol % show pronounced triple SMEs in the dynamic mechanical thermal analysis (DMTA) and visual observation. This new strategy of chemically cross-linked immiscible blends with cocontinuous architecture can be used to design and prepare new SMPs with triple SMEs.

In the real world, a large amount of data can be described by networks using relations between data. The data described by networks can be called networked data. Classification is one of the main tasks in analyzing networked data. Most of the previous methods find the class of the unlabeled node using the classes of its neighbor nodes. However, in the networks with heterophily, most of connected nodes belong to different classes. It is hard to get the correct class using the classes of neighbor nodes, so the previous methods have a low level of performance in the networks with heterophily. In this paper, a probabilistic method is proposed to address this problem. Firstly, the class propagating distribution of the node is proposed to describe the probabilities that its neighbor nodes belong to each class. After that, the class propagating distributions of neighbor nodes are used to calculate the class of the unlabeled node. At last, a classification algorithm based on class propagating distribution is presented in the form of matrix operations. In empirical study, we apply the proposed algorithm to the real-world datasets, compared with some other algorithms. The experimental results show that the proposed algorithm performs better when the networks are of heterophily.

In this work, the improved self-healing of cross-linked polyethylene (PE) (cPE)/carbon black (CB) nanocomposites by their shape memory effect (SME) is investigated. CB nanoparticles are found to be homogeneously dispersed in the PE matrix and significantly increase the strength of the materials. Compared with the breaking of linear PE (lPE) at the melting temperature (T(m)), the cPE and cPE/CB nanocomposites still have high strength above T(m) due to the formation of networks. The cPE and cPE/CB nanocomposites show both high strain fixity ratio (R(f)) and high strain recovery ratio (R(r)). Crystallization-induced elongation is observed for all the prepared shape memory polymer (SMP) materials and the effect becomes less remarkable with increasing volume fraction of CB nanoparticles (v(CB)). The scratch self-healing tests show that the cross-linking of PE matrix, the addition of CB nanoparticles, and the previous stretching in the direction perpendicular to the scratch favor the closure of the scratch and its complete healing. This SME-aided self-healing could have potential applications in diverse fields such as coating and structure materials.

Two hollow fiber membrane bioreactors (HFMBRs) inoculated with activated sludge were used in series to biodegrade continuously mixed xylene. The influence of gas residence time (τ) and mass loading rate (LR) on elimination capacity (EC) of the mixed xylene was investigated. A maximum elimination capacity (EC(max,v)) of 466gm(-3)h(-1) was achieved at τ=10s and LR(v)=728gm(-3)h(-1). Thereafter, ozone was introduced into inlet gas and the influence of ozone was investigated. Results showed that the maximum xylene elimination capacity increased from 524gm(-3)h(-1) to 568gm(-3)h(-1) and 616gm(-3)h(-1) at τ=10s, respectively when the inlet ozone concentration rose from 200mgm(-3) to 400mgm(-3) and 600mgm(-3), respectively. HFMBR coupled with O(3) has higher performance and stability for the long-term operation at the same condition., (Copyright © 2012 Elsevier Ltd. All rights reserved.)