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For photoelectrodes to be used in practical catalytic applications, challenges exist in achieving the efficient production and transport of photogenerated charge-separated states. Analogous concepts in traditional inorganic photoelectrodes can be applied to their organic-polymer counterparts with improved charge-separation efficiencies. In this work, we develop photoconductive organic networks to form a high-performance photoelectrode for NO3–reduction to NH3. In the integrated network, interfaces between the organic electron-donating photoconductor and electron-accepting catalyst can generate charge carriers efficiently upon illumination, leading to enhanced charge separation for photoelectrocatalysis. The photoelectrode network is capable of converting NO3–to NH3at an external quantum efficiency of 13%. By coupling with a BiVO4photoanode in tandem, the system reduces NO3–to NH3and oxidizes H2O to O2simultaneously at Faradaic efficiencies of 95–98% with sustained photocurrents and production yields. Investigation of the photoconductive network by steady-state/time-resolved spectroscopies reveals the efficient generation and transport of free charge carriers in the photoelectrode, providing a basis for high photoelectrocatalytic performances.

ABSTRACTType IIA topoisomerase (TOP2A) is upregulated in hepatocellular carcinoma (HCC) and its expression is positively correlated with poor prognosis. However, the underlying molecular mechanism of this connection are poorly understood. Hence, the present work aimed to examine the possible mechanisms which may be useful in identifying a potential therapeutic strategy. The differential expression of TOP2A mRNA in HCC as compared with adjacent normal tissue was analyzed using the Oncomine database. The expression levels of TOP2A in HCC specimens and cell lines were assessed by Western blot and RT-qPCR. Stable cell lines were generated to knockdown or overexpress TOP2A, and then cell growth, migration, and invasion were analyzed. Furthermore, this study examined epithelial-mesenchymal transition (EMT) as well as the activation of related pathways. Additionally, the correlation between TOP2A levels and E-cadherin/Snail expression was determined in 72 HCC specimens. Higher expression levels of TOP2A were observed in HCC in Oncomine datasets, and the results were verified using 40 pairs of HCC specimens and peritumoral tissues. TOP2A expression levels were remarkably elevated in cells with great metastatic capacity. In addition, HCC cell growth, migration, and invasion were suppressed after TOP2A knockdown in MHCC97H cells (MHCC97H-shRNA-TOP2A), while these capabilities were promoted in TOP2A-overexpressing Hep3B cells (Hep3B-TOP2A). Furthermore, EMT was inhibited in MHCC97H-shRNA-TOP2A cells, but induced in Hep3B-TOP2A cells. The induction of EMT by TOP2A was shown to be mediated by Snail, as TOP2A promoted Snail expression through the p-ERK1/2/p-SMAD2 signaling pathway. TOP2A level showed a negative correlation with E-cadherin, whereas a positive correlation with that of vimentin and Snail in human HCC specimens by immunohistochemistry analyses. Kaplan–Meier survival curves revealed that TOP2A upregulation showed a positive correlation with poor prognosis patients. Taken together, TOP2A possibly enhances the metastasis of HCC by promoting EMT through the mediation of the p-ERK1/2/p-SMAD2/Snail pathway. This indicates that TOP2A maybe a potential factor to predict the prognosis of HCC.

Inspired by the porous structures of photosynthetic organelles, we report here a new type of photoelectrode based on a standalone macroporous conjugated polymer network (MCN) that converts sunlight into high-energy electrons for CO2reduction to CH3OH. The MCN provides supramolecular cavities with sufficient functional groups that control the structures of photocatalytic assemblies, which circumvents the geometric limitations of traditional inorganic counterparts. Stabilized interfacial contact between MCN and photocatalysts is achieved by strong chemical linkages throughout the network. Solar irradiation of MCN with a cobalt-based catalyst generates highly reducing electrons for the reduction of CO2to CH3OH at a conversion efficiency of 70%. Production of CH3OH sustains for at least 100 h, with a small decrease in yield rates. Scaling up the photoelectrode from 1 to 100 cm2results in photocurrent generation stabilized at 0.25 A and continuous CH3OH production at a conversion efficiency of 85%, demonstrating the scalability and high performances.

ABSTRACTA disintegrin and a metalloprotease (ADAM)9 upregulated within human hepatocellular carcinoma (HCC) cells, but its effect on HCC radiosensitivity remains unknown. The present work aimed to examine the effect of ADAM9 on HCC radiosensitivity and to reveal its possible mechanism, which may be helpful in identifying a potential therapeutic strategy. Changes in ADAM9 expression after X-ray irradiation were identified using western blot, qRT-PCR, and immunofluorescence. ADAM9 stable knockdown and overexpression cell lines were constructed using lentivirus packaging. The radiosensitivity of HCC cells with altered ADAM9 expression was examined by CCK-8 assays, subcutaneous tumorigenesis experiments, and clone formation assays. This study also determined how autophagy affected HCC cell radiosensitivity. Furthermore, ADAM9, p62 and Bax expressions in HCC tissues that were removed after radiotherapy were detected by immunohistochemistry, and the relationship among the levels of these molecules was statistically analyzed. The level of ADAM9expression in HCC cells increased after X-ray irradiation. Through CCK-8 assays, subcutaneous tumorigenesis experiments, and clone formation assays, this work discovered the increased MHCC97H cell radiosensitivity after ADAM9 knockdown, and the radiosensitivity of Huh7 cells decreased after the overexpression of ADAM9. Furthermore, ADAM9 induced HCC cell autophagy via downregulating Nrf2 expression, while autophagy inhibition or induction reversed the effects of altered ADAM9 expression on radiosensitivity. Moreover, ADAM9 level showed a negative correlation with Bax and p62 expression within HCC tissues after radiotherapy. Taken together, ADAM9 decreased the radiosensitivity of HCC cells, and autophagy mediated this process.

Radiation-induced heart damage is a serious side effect caused by radiotherapy, especially during the treatment of cancer near the chest. Trimetazidine is effective at reducing inflammation in the heart, but how it affects radiation-induced cardiac fibrosis (RICF) is unknown. To investigate the potential effect and molecular mechanism, we designed this project with a C57BL6 male mouse model supposing trimetazidine could inhibit RICF in mice. During the experiment, mice were randomly divided into six groups including a control group (Con), radiation-damaged model group (Mod) and four experimental groups receiving low-dose (10 mg/kg/day) or high-dose (20 mg/kg/day) trimetazidine before or after radiation treatment. Apart from the control group, all mice chests were exposed to 6 MV X-rays at a single dose of 20 Gy to induce RICF, and tissue analysis was done at 8 weeks after irradiation. Fibroblast or interstitial tissues and cardiac fibrosis-like characteristics were determined using haematoxylin and eosin and Masson staining, which can be used to assess myocardial fibrosis. Immunohistochemical analysis and RT-PCR were used to determine gene expression and study the molecular mechanism. As a result, this study suggests that trimetazidine inhibits RICF by reducing gene expression related to myocyte apoptosis and fibrosis formation, i.e. connective tissue growth factor (CTGF), transforming growth factor (TGF)-β1, smad2 and smad3. In conclusion, by regulating the CTGF/TGF-β1/Smad pathway, trimetazidine could be a prospective drug for clinical treatment of RICF.

Cancer is a refractory disease, which brings physical, mental and economic sufferings on patients and their families. The activation of oncogenes and/or the deletion of tumor repressors result in uncontrolled tumor survival and proliferation. Therapeutic resistance and cancer recurrence are common issues during the course of clinical treatment. Since each single treatment can’t eradicate tumor cells completely, the development of combinatorial therapeutic regimen is in the spotlight for several decades. Combinatorial therapeutic regimen, a treatment modality that combines two or more therapeutic agents, targets key pathways in a characteristically synergistic or an additive manner. It aims to improve the efficacy and magnitude of therapeutic responses and reduce the likelihood of acquired resistance by using optimal drug dose with tolerable side effect. Currently, the combinatorial therapeutic regimen not only includes various chemicals, but also diverse therapeutic modalities which affected DNA damage repair, protein localization and degradation, post-translational modification, cell metabolism and apoptosis, as well as immune response.