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High‐temperature proton‐exchange membrane fuel cells (HT‐PEMFCs) fabricated with phosphoric acid (PA)‐doped polybenzimidazole (PBI) show apparent technical advantages. In practical automotive applications, achieving cold start‐up capability is crucial. In this work, a kind of branched block proton exchange membrane (PEM) based on PBI with a low content of porphyrin ring (<1 mol.%) is reported as a branched monomer. Self‐assembly into high‐density helical nanochannels under the synergistic effect of phase separation and porphyrin π−π stacking, thus the PEM can maintain a high level of PA doping. Specifically, the PA/1.8TCPP‐BrPy‐OPBI membrane shows a proton conductivity of 0.169 and 0.071 S cm−1, as well as an H2‐O2 fuel cell peak power density of 1077 and 357 mW cm−2 at 180 and 80 °C without humidification and backpressure, respectively. The membrane electrode assembly (MEA) can exhibit good fuel cell stability, with a voltage decay rate of only 7.0 µV h−1 at 80 °C. Furthermore, it maintains a peak power density of 93% even after 150 start‐up/shut‐down cycles at 25 °C. This work expands the operating temperature range of conventional PBI membranes between 25 and 200 °C and thus provides a novel strategy for high‐performance PBI‐based HT‐PEMFCs. [ABSTRACT FROM AUTHOR]

Constructing a functional layer on the surface of commercial membrane (as a substrate) to inhibit the formation of biofilms is an efficient strategy to prepare an antibacterial anion exchange membrane (AEM). Herein, a rechargeable multifunctional anti‐biological system is reported by utilizing the mussel‐inspired L‐dopa connection function on commercial AEMs. Cobalt nanoparticles (Co NPs) and N‐chloramine compounds are deposited on the AEM surface by a two‐step modification procedure. The anti‐biofouling abilities of the membranes are qualitatively and quantitatively analyzed by adopting common Gram‐negative (E. coli) and Gram‐positive (S. aureus & Bacillus) bacteria as model biofouling organisms. The optimized membrane exhibits a high stability concerning the NaCl solution separation performance within 240 min. Meantime, the mechanism of the anti‐adhesion is un‐veiled at an atomic level and molecular dynamics (MD) simulation are conducted to measure the interaction, adsorption energy and average loading by using lipopolysaccharide (LPS) of E. coli. In view of the superior performance of antibacterial surfaces, it is believed that this work could provide a valuable guideline for the design of membrane materials with resistance to biological contamination. [ABSTRACT FROM AUTHOR]

Background: Liver resection is the mainstay of curative treatment for intrahepatic cholangiocarcinoma (ICC) while the postoperative prognosis varies greatly, with no recognized biomarker. We aimed to identify the plasma metabolomic biomarkers that could be used for preoperative risk stratification of ICC patients. Methods: 108 eligible ICC patients who underwent radical surgical resection between August 2012 and October 2020 were enrolled. Patients were randomly divided into a discovery cohort (n = 76) and a validation cohort (n = 32) by 7:3. Metabolomics profiling of preoperative plasma was performed and clinical data were collected. The least absolute shrinkage and selection operator (LASSO) regression, Cox regression, and receiver operating characteristic (ROC) analyses were used to screen and validate the survival-related metabolic biomarker panel and construct a LASSO-Cox prediction model. Results: 10 survival-related metabolic biomarkers were used for construction of a LASSO-Cox prediction model. In the discovery and validation cohorts, the LASSO-Cox prediction model achieved an AUC of 0.876 (95%CI: 0.777–0.974) and 0.860 (95%CI: 0.711–1.000) in evaluating 1-year OS of ICC patients, respectively. The OS of ICC patients in the high-risk group was significantly worse than that in the low-risk group (discovery cohort, p < 0.0001; validation cohort: p = 0.041). Also, the LASSO-Cox risk score (HR 2.43, 95%CI: 1.81–3.26, p < 0.0001) was a significant independent risk factor associated with OS. Conclusions: The LASSO-Cox prediction model has potential as an important tool in evaluating the OS of ICC patients after surgical resection and can be used as prediction tools to implement the best treatment options that could result in better outcomes. [ABSTRACT FROM AUTHOR]

Traffic sign detection is an important research direction in the process of intelligent transportation in the Internet era, and plays a crucial role in ensuring traffic safety. The purpose of this research is to propose a traffic-sign-detection algorithm based on the selective kernel attention (SK attention), explicit visual center (EVC), and YOLOv5 model to address the problems of small targets, incomplete detection, and insufficient detection accuracy in natural and complex road situations. First, the feature map with a smaller receptive field in the backbone network is fused with other scale feature maps to increase the small target detection layer. Then, the SK attention mechanism is introduced to extract and weigh features at different scales and levels, enhancing the attention to the target. By fusing the explicit visual center to gather local area features within the layer, the detection effect of small targets is improved. According to the experiment results, the mean average precision (mAP) on the Tsinghua-Tencent Traffic Sign Dataset (TT100K) for the proposed algorithm is 88.5%, which is 4.6% higher than the original model, demonstrating the practicality of the detection of small traffic signs. [ABSTRACT FROM AUTHOR]

Background Insufficient post-operative future liver remnant (FLR) limits the feasibility of hepatectomy for patients. Staged hepatectomy is an effective surgical approach that can improve the resection rate of hepatocellular carcinoma (HCC). This study aimed to compare the safety and efficacy of laparoscopic microwave ablation and portal vein ligation for staged hepatectomy (LAPS) and classical associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) in the treatment of hepatitis B virus (HBV)-related HCC. Methods Clinical data of patients with HBV-related HCC who underwent LAPS or ALPPS in our institute between January 2017 and May 2022 were retrospectively analysed. Results A total of 18 patients with HBV-related HCC were retrospectively analysed and divided into the LAPS group (n  =   9) and ALPPS group (n  =   9). Eight patients in the LAPS group and eight patients in the ALPPS group proceeded to a similar resection rate (88.9% vs 88.9%, P  =   1.000). The patients undergoing LAPS had a lower total comprehensive complication index than those undergoing ALPPS but there was not a significant different between the two groups (8.66 vs 35.87, P  =   0.054). The hypertrophy rate of FLR induced by ALPPS tended to be more rapid than that induced by LAPS (24.29 vs 13.17 mL/d, P  =   0.095). The 2-year recurrence-free survival (RFS) was 0% for ALPPS and 35.7% for LAPS (P  =   0.009), whereas the 2-year overall survival for ALPPS and LAPS was 33.3% and 100.0% (P  =   0.052), respectively. Conclusions LAPS tended to induce lower morbidity and FLR hypertrophy more slowly than ALPPS, with a comparable resection rate and better long-term RFS in HBV-related HCC patients. [ABSTRACT FROM AUTHOR]

Objectives: Pretreatment evaluation of tumor biology and microenvironment is important to predict prognosis and plan treatment. We aimed to develop nomograms based on gadoxetic acid-enhanced MRI to predict microvascular invasion (MVI), tumor differentiation, and immunoscore. Methods: This retrospective study included 273 patients with HCC who underwent preoperative gadoxetic acid-enhanced MRI. Patients were assigned to two groups: training (N = 191) and validation (N = 82). Univariable and multivariable logistic regression analyses were performed to investigate clinical variables and MRI features' associations with MVI, tumor differentiation, and immunoscore. Nomograms were developed based on features associated with these three histopathological features in the training cohort, then validated, and evaluated. Results: Predictors of MVI included tumor size, rim enhancement, capsule, percent decrease in T1 images (T1D%), standard deviation of apparent diffusion coefficient, and alanine aminotransferase levels, while capsule, peritumoral enhancement, mean relaxation time on the hepatobiliary phase (T1E), and alpha-fetoprotein levels predicted tumor differentiation. Predictors of immunoscore included the radiologic score constructed by tumor number, intratumoral vessel, margin, capsule, rim enhancement, T1D%, relaxation time on plain scan (T1P), and alpha-fetoprotein and alanine aminotransferase levels. Three nomograms achieved good concordance indexes in predicting MVI (0.754, 0.746), tumor differentiation (0.758, 0.699), and immunoscore (0.737, 0.726) in the training and validation cohorts, respectively. Conclusion: MRI-based nomograms effectively predict tumor behaviors in HCC and may assist clinicians in prognosis prediction and pretreatment decisions. Key Points: • This study developed and validated three nomograms based on gadoxetic acid-enhanced MRI to predict MVI, tumor differentiation, and immunoscore in patients with HCC. • The pretreatment prediction of tumor microenvironment may be useful to guide accurate prognosis and planning of surgical and immunological therapies for individual patients with HCC. [ABSTRACT FROM AUTHOR]

A series of gentamicin‐modified anion exchange membranes (AEMs) immobilized by mussel‐inspired dopamine coating is prepared in this work. The purpose is to improve antibacterial activity and fouling resistance of the commercial AEMs (AEM Type I, Fujifilm Co.). As a result of the applied modification, the hydrophilicity of membrane surface improved significantly. Thus, the as‐prepared modified AEMs exhibit the good antifouling property, in electrodialysis (ED) experiments by using the sodium dodecylbenzenesulfonate and albumin from bovine serum as model foulants. Furthermore, taking into account the results of the antibacterial test, the resulting modified AEMs exhibit improved antibacterial property for Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). After a brief contact with bacteria, the antibacterial rates of modified AEMs coating with gentamicin‐based polymer are 80.11% for E. coli and 90.66% for S. aureus, which are much higher than pristine AEM (6.28% and 9.07%), respectively. In addition, the modified membrane has good operational stability during ED process and recovery ability after contamination, and also maintains satisfactory electrochemical properties. This investigation highlights a design of simple strategy for the preparation of antimicrobial and antifouling AEM, which can be used for ED. [ABSTRACT FROM AUTHOR]

A series of amphoteric semi-interpenetrating polymer network ion-exchange membranes (AsIPN IEMs), composed of fluoro-methyl sulfonated poly(arylene ether ketone) (SPAEK) copolymer and in situ polymerized sulfobetaine acrylamide (SBMA), has been fabricated. In this work, the SPAEK serving as a linear polymer chain is expected to guarantee the ion conductivity and mechanical and dimensional stability, while polymerized SBMA with ion pairs can moderately narrow the ion channel reducing the anion transportation in AsIPN matrix via ionic cross-linkings. In particular, the thermogravimetric analysis demonstrates the presence of ionic cross-linking in AsIPN-X IEM matrix due to the degradation temperature of sulfonated groups shifting from ca. 350 to ca. 340 °C. In applications, electrodialysis (ED) with AsIPN-10 IEM shows the highest NaCl removal ratio of 89.6% within 110 min, outperforming 60SPAEK (83.5%) commercial CEM-Type-II (86.1%). These demonstrate AsIPN-10 IEM has the potential in rendering ED of improved performance for separation application. [ABSTRACT FROM AUTHOR]

Background: Stress-Inducible Protein-1 (STIP1) is a co-chaperone that associates directly with heat shock proteins, and regulates motility of various types of cancer. In the present study, we investigated the role of STIP1 on metastasis of gastric cancer (GC). Methods: In vivo metastatic experimental model was employed to investigate the effect of STIP1 on metastasis of GC cells. Loss-of-function and gain-of-function experiments were performed to examine the role of STIP1 on metastasis of GC cells. Western blot, immunofluorescence staining, migration and invasion assays, microarray and KEGG pathway analysis were applied to explore the underlying mechanism. Results: In current study, we demonstrated that STIP1 promoted lung metastasis of GC cells in vivo. Furthermore, STIP1 significantly enhanced migration and invasion abilities of GC cells. In contrast, knock-down of STIP1 yielded the opposite effects on these phenotypes in vitro. STIP1 promoted tumor metastasis through inducing epithelial-tomesenchymal transition in GC cells. Mechanistically, STIP1 promoted GC metastasis via up-regulation of targeted genes in Wnt/β-catenin signaling pathway, including c-Myc and Cyclin D1, and accompanied with nuclear translocation of β-catenin. Conclusions: Our findings indicate that elevated expression of STIP1 exhibited a metastasis-promoting effect in GC cells through activation of Wnt/β-catenin signaling pathway. STIP1 may be served as a potential therapeutic target for preventing GC metastasis. [ABSTRACT FROM AUTHOR]

A series of thermally stable poly(arylene ether ketone)s (PAEKs) bearing benzimidazole structure in the main chains, named poly(arylene ether ketone-benzimidazole)s (PAEK-BIs), were directly synthesized by polycondensation of dimethyl bisphenol, dibenzimidazole bisphenol, and difluorobenzophenones. By systematically varying the amount ratio of two kind of bisphenols, the content of benzimidazole moiety in the backbone was controlled straightforwardly. The prepared amorphous polymers were characterized in terms of Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, thermal, dielectric, and gas transport properties. Evaluation of solubility reveals that PAEK-BIs with >60% content of benzimidazole units could be soluble in commonly used organic solvents. Also polymers containing content-tunable benzimidazole show high glass-transition temperatures (Tg's, 157- 319°C) and excellent thermal stability (e.g., temperature of 5% weight loss, above 438°C in air). Dielectric constants of PAEK-BIs measured at 25°C are all less than 2.66 in the frequency range of 0.1-50 kHz. For dense films, the ideal gas selectivity and permeability coefficients could be compared with that of commercial Ultem 1000 membrane, which indicate that the PAEK-BIs are potential to be used for gas separation membrane material. [ABSTRACT FROM AUTHOR]

The synthesized hydrophilic polymers [poly (vinyl butyral) (PVB) and cationic PVB (CPVB)] blended with poly (vinylidene fluoride) (PVDF) were used to fabricate hydrophilic ultrafiltration membranes. A visual inspection method and a glass transition temperature method were applied to study the miscibility of PVDF/PVB and PVDF/CPVB blend systems. The results showed that the PVDF/PVB was an immiscible blend and the PVDF/CPVB was a partially miscible blend. Dynamic contact angle experiments showed that the hydrophilicity of the blend membranes was significantly improved with the addition of PVB and CPVB. The pure water permeation (PWP) of blend membranes increased with the content of PVB and CPVB. [ABSTRACT FROM AUTHOR]

Developing monovalent cation permselective membranes (MCPMs) with high-efficient permselectivity is the core concern in specific industrial applications. In this work, we have fabricated a series of novel cation exchange membranes (CEMs) based on sulfonated polysulfone (SPSF) surface modification by polyethyleneimine (PEI) and 4′-aminobenzo-12-crown-4 (12C4) codeposited with dopamine (DA) successively, which was followed by the cross-linking of glutaraldehyde (GA). The as-prepared membranes before and after modification were systematically characterized with regard to their structures as well as their physicochemical and electrochemical properties. Particularly, the codeposition sequence of modified ingredients was investigated on galvanostatic permselectivity to cations. The modified membrane (M-12C4-0.50-PEI) exhibits significantly prominent selectivity to Li+ ions ( P Mg 2 + Li + = 5.23) and K+ ions ( P Mg 2 + K + = 13.56) in Li+/Mg2+ and K+/Mg2+ systems in electrodialysis (ED), which is far superior to the pristine membrane (M-0, P Mg 2 + Li + = 0.46, P Mg 2 + K + = 1.23) at a constant current density of 5.0 mA·cm−2. It possibly arises from the synergistic effects of electrostatic repulsion (positively charged PEI), pore-size sieving (distribution of modified ingredients), and specific interaction effect (12C4 ~Li+). This facile strategy may provide new insights into developing selective CEMs in the separation of specific cations by ED. [ABSTRACT FROM AUTHOR]

Background: Limited effective intervention for advanced hepatocellular carcinoma (HCC) is available. This study aimed to investigate the potential clinical utility of apatinib, a highly selective inhibitor of the vascular endothelial growth factor receptor-2 (VEGFR2) tyrosine kinase, as a radiosensitizer in the treatment of HCC. Methods: Four human HCC cell lines SMMC-7721, MHCC-97H, HCCLM3 and Hep-3B were treated with apatinib, irradiation or combination treatment. Colony formation assay, flow cytometry and nuclear γ-H2AX foci immunofluorescence staining were performed to evaluate the efficacy of combination treatment. RNA sequencing was conducted to explore the potential mechanism. The impact of combination treatment on tumor growth was assessed by xenograft mice models. Results: Colony formation assay revealed that apatinib enhanced the radiosensitivity of HCC cell lines. Apatinib suppressed repair of radiation-induced DNA double-strand breaks. Flow cytometry analysis showed that apatinib increased radiation-induced apoptosis. Apatinib radiosensitized HCC via suppression of radiation-induced PI3K/AKT pathway. Moreover, an in vivo study indicated apatinib combined with irradiation significantly decreased xenograft tumor growth. Conclusions: Our results indicate that apatinib has therapeutic potential as a radiosensitizer in HCC, and PI3K/AKT signaling pathway plays a critical role in mediating radiosensitization of apatinib. [ABSTRACT FROM AUTHOR]

A facile membrane surface modification process for improving permselectivity and antimicrobial property was proposed. A polydopamine (PDA) coating was firstly fabricated on pristine anion exchange membrane (AEM), followed by in situ reduction of Ag without adding any extra reductant. Finally, 2,5-diaminobenzene sulfonic acid (DSA) was grafted onto PDA layer via Michael addition reaction. The as-prepared AEM exhibited improved permselectivity (from 0.60 to 1.43) and effective inhibition of bacterial growth. In addition, the result of the long-term (90-h continuous electrodialysis) test expressed the excellent durability of the modified layer on membrane surface, because the concentration of Cl− and SO42− in diluted chamber fluctuated ~0.024 and 0.030 mol·L−1 with no distinct decline. The method described in this work makes the full use of multifunctional PDA layer (polymer-like coating, in situ reduction and post-organic reaction), and a rational design of functional AEM was established for better practical application. [ABSTRACT FROM AUTHOR]

The fouling mitigation of anion exchange membrane (AEM) performance is a great challenge faced by many membrane applications (e.g., electrodialysis, ED). In this study, a novel AEM is modified with dual functional layers prepared by coating hydrophilic polydopamine (PDA) on quaternized poly(2,6‐dimethyl‐1,4‐phenylene oxide), and subsequently grafting with zwitterionic structure of sulfobetaine methacrylate via the aza‐Michael reaction, aiming to improve the membrane fouling resistant. In particular, the sodium dodecyl benzene sulfonate (SDBS) is used as model foulant. The hydrophilic layer (PDA) and hydrophilic/negatively charged zwitterionic surface of AEM, act as useful barriers via physical blocking and electrostatic repulsion, respectively. The proposed modification can restrict the deposition and/or chemical adsorption of SDBS. The time elapsed until the occurrence of fouling (transition time) is significantly enhanced as result of modification (around five times longer) as evidence of the reinforced antifouling property. The enhanced performance of modified membrane is also confirmed by desalting experiments in terms of NaCl rejection potential. The facile preparation and advanced performances of dual functional layers modified AEM suggest its potential ED application. In this study, a novel anion exchange membrane is modified with dual functional layers prepared by coating hydrophilic polydopamine (PDA) on quaternized poly(2,6‐dimethyl‐1,4‐phenylene oxide), and subsequently grafting with zwitterionic structure of sulfobetaine methacrylate via the aza‐Michael reaction, aiming to improve the membrane fouling resistant. [ABSTRACT FROM AUTHOR]