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Background: Melanoma, the most threatening cancer in the skin, has been considered to be driven by the carcinogenic RAF-MEK1/2-ERK1/2 signaling pathway. This signaling pathway is usually mainly dysregulated by mutations in BRAF or RAS in skin melanomas. Although inhibitors targeting mutant BRAF, such as vemurafenib, have improved the clinical outcome of melanoma patients with BRAF mutations, the efficiency of vemurafenib is limited in many patients. Methods: Spearman correlation analysis was performed to determine the relationship between blood bilirubin and clinical outcomes in a retrospective study. In vitro and in vivo assays were used to determine the effect of bilirubin on the sensitivity of melanoma cells to vemurafenib. Findings: Blood bilirubin in patients with BRAF-mutant melanoma treated with vemurafenib is negatively correlated with clinical outcomes. In vitro and animal experiments show that bilirubin can abrogate vemurafenib-induced growth suppression of BRAF-mutant melanoma cells. Moreover, bilirubin can remarkably rescue vemurafenib-induced apoptosis. Mechanically, the activation of ERK-MNK1 axis is required for bilirubin-induced reversal effects post vemurafenib treatment. Interpretation: Our findings not only demonstrate that bilirubin is an unfavorable for patients with BRAF-mutant melanoma who received vemurafenib treatment, but also uncover the underlying mechanism by which bilirubin restrains the anticancer effect of vemurafenib on BRAF-mutant melanoma cells. Funding: National Natural Science Foundation of China (81773213 and 81972399), Natural Science Foundation research team of Guangdong Province (2018B030312001), and the open research funds from the Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital (202011-204, 202011-106). Declaration of Interest: None to declare Ethical Approval: This study was approved by Institutional Animal Care and Use Committee.

Both introducing oxygen vacancies (OVs) and enhancing charge transfer efficiency (CTE) have been proved to be effective strategies to improve the capability of the catalyst to activate peroxymonosulfate (PMS). The OVs on catalysts can promote the CTE of the catalyst/PMS oxidation system. However, current OVs introduction methods can only lead to very limited CTE enhancement. Here, the synthesis of CoP/CoOx heterostructured nanoparticles with abundant OVs and dramatically enhanced CTE through a reliable partial phosphidation method using ZIF-67 as a precursor was reported. The excellent CTE of the CoP/CoOx/PMS oxidation system was the result of the synergy of increased OVs and introduced CoP with high conductivity. When served as Fenton-like catalyst for tetracycline (TC) degradation via activating PMS, due to the synergy between abundant OVs and high CTE, CoP/CoOx exhibited superior performance for TC removal, with the pseudo-second-order kinetic rate constant ∼ 10.3 and 77.4 times that of CoPx and Co3O4, respectively. Moreover, the cobalt leakage (0.06 mg/L) was only about 1/2 and 1/3 of that of CoPx and Co3O4, respectively. The mechanism study suggested that SO4•−, •OH and O2•− played an important role in TC degradation. The excellent catalytic performance of CoP/CoOx was attributed to its abundant OVs and high CTE to generate more active oxygen species. This work provides new insights for designing and developing efficient catalysts for wastewater treatment via Fenton-like process.

The composite comprised of graphene and carbon nanotubes (CNTs) exhibited significantly enhanced electrochemical performance due both to the improved dispersion and inhibition of restacking of graphene and CNTs. In this work, graphene nanoribbons (GNRs)/CNTs composite (GNRs/CNTs) was synthesized on gram-scale by chemical vapor deposition. Under optimal growth conditions, the yield of GNRs/CNTs as high as 26 g per gram catalyst could be achieved in 30 min growth time. The morphology and quality of the as-synthesized composite was verified by using SEM, TEM and Raman spectroscopy. The electrochemical properties of GNRs/CNTs was evaluated using cyclic voltammetry (CV) and galvanostatic charge-discharge techniques. GNRs/CNTs exhibited specific capacitance of 242.3 F/g at 0.5 A g-1, which was over 4 times of that of CNTs. The GNRs/CNTs based electrodes exhibited excellent cycling stability at 1 A g-1 for over 4000 cycles, which can be attributed to the excellent electrical conductivity and the unique structure. When employed as electrode for membrane capacitive desalination, the desalination capacity of 16.46 mg g-1 has been achieved under 1.2 V with 500 mg L-1 NaCl solution as feeding water.

Two dimensional (2D) metal oxide are expected to be better adsorbents for heavy metal ions than their other low dimensional counterparts. In this work, non-layered 2D Fe2O3 nanosheets were synthesized by a simple combustion method and tested for Pb(II) removal from aqueous solution. The 2D Fe2O3 nanosheets exhibited high crystallinity and purity as confirmed by powder x-ray diffraction. As revealed by scanning electron microscope (SEM) and transmission electron microscope (TEM), the nanosheets with lateral size up to hundreds of microns that made it easy to be recollected after water treatment. The results of XRD and TEM indicated that the nanosheets showed preferentially exposed surfaces of (1 0 0), which has strong affinity for Pb(II). The nanosheets exhibited a moderate specific surface area of 12.19 m2/g with a small pore volume of 0.034 mL/g. The nanosheets exhibited excellent adsorption performance for Pb(II) in pH range from 3.0 to 6.0. The adsorption of Pb(II) conformed to the Langmuir isotherm model with the theoretical maximum adsorption capacity of Pb(II) estimated to be 436.83 mg/g. Kinetics study indicated that the adsorption process followed pseudo-second-order kinetics model. Based on the X-ray photoelectron spectroscopy and FTIR results of the nanosheets before and after Pb(II) adsorption, the adsorption of Pb(II) was dominated by the surface complexation and ion exchange of Pb(II) ions with surface hydroxyl groups. Given the low preparation cost and the excellent adsorption capacity, the non-layered 2D Fe2O3 nanosheets holds great potential as adsorbent for Pb(II) removal.

Biosurfactant is known as an efficient accelerator for hydrocarbon biodegradation by enhancing their bioavailability and facilitating their degradation by microorganisms. The present work aimed to characterize the structure of the biosurfactant produced by Paracoccus sp. MJ9 and to evaluate its potential use in diesel degradation in marine environment. In the present study, an efficient biosurfactant-producing strain, namely, Paracoccus sp. MJ9, was selected using an oil spreading test, drop collapse method and surface tension test in four petroleum-degrading strains isolated from Jiaozhou Bay in Qingdao, Shandong Province. Results showed that the surface-active substance produced by the strain MJ9 reduced the surface tension of water from 65.56 mN/m to 38.33 mN/m. Results of thin-layer chromatography analysis (TLC), fourier transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (1H NMR) spectroscopy analysis indicated that the surface-active substance was rhamnolipid. Furthermore, diesel oil with MJ9 or crude biosurfactant produced by MJ9 was qualitatively analyzed by gas chromatography and mass spectrometry before and after biodegradation. Results showed that the removal efficiency of 81 % was achieved within 5 days. This work has screened and identified a bacterium with superior biosurfactant production capabilities, characterized the biosurfactant as rhamnolipid and indicated the potential applications in bioremediation processes to enhance the solubility of hydrophobic compounds.