Hydroxychloroquine enhances anticancer effect of DOX/folate-phytosterol-carboxymethyl cellulose nanoparticles in A549 lung cancer cells

Purpose: To study the in vitro anticancer effect of doxorubicin-loaded folate-phytosterol-carboxymethyl cellulose nanoparticles (DOX/FPCMC NPs), alone and in combination with the antimalarial drug hydroxychloroquine (HCQ) on human lung cancer cells (A549 cells). Methods: Human lung adenocarcinoma A549 cell line was treated with blank FPCMC NPs, HCQ, free DOX, DOX/FPCMC NPs, free DOX + HCQ or DOX/FPCMC NPs + HCQ. The concentrations of HCQ, DOX and FPCMC NPs varied within the ranges of 20-120 μmol/L, 2-12 mg/L and 50-500 mg/L, respectively. Cell viability and free folate competitive inhibition were determined using MTT assay. Cell proliferation and migration were investigated with wound healing assay, while confocal laser scanning microscopy (CLSM) was used to determine cellular uptake of drugs. Results: In all formulations, the DOX/FPCMC NPs + HCQ produced the highest cytotoxicity in A549 cells due to high cytotoxicity arising from folate-receptor-mediated endocytosis and HCQ-induced inhibition of autophagy. Free folate competitively inhibited the cytotoxicity of DOX/FPCMC NPs on A549 cells. Wound healing assay showed that A549 cells treated with DOX/FPCMC NPs + HCQ had the lowest cell levels of proliferation and migration capacity. The cellular uptake of DOX/FPCMC NPs by A549 cells was higher than that of free DOX. Conclusion: The combination of DOX/FPCMC NPs and HCQ produced the best antitumor effect and had a promising potential for reversal of MDR Keywords: Folate-phytosterol-carboxymethyl cellulose, Doxorubicin, Hydroxychloroquine, Anticancer, Lung cance

Facile One-Pot Synthesis of Self-Assembled Folate-Biotin-Pullulan Nanoparticles for Targeted Intracellular Anticancer Drug Delivery

The self-assembled folate-biotin-pullulan (FBP) nanoparticles (NPs) were prepared by facile one-pot synthesis and their physicochemical properties were characterized. The self-assembled FBP NPs were used as an anticancer drug nanocarrier entrapping doxorubicin (DOX) for targeting folate-receptors-overexpressing cancer cells. The identification of prepared NPs to folate-receptor-expressing cancer cells (KB cells) was affirmed by cell viability measurement, folate competition test, and flow cytometric analysis. Compared with the naked DOX and DOX/BP NPs, the DOX/FBP NPs had lower IC50 value compared to KB cells as a result of the folate-receptor-mediated endocytosis process. The cytotoxicity of DOX/FBP NPs to KB cells could be inhibited competitively by free folate. The cellular intake pattern of naked DOX and drug-loaded NPs was identified by confocal laser scanning microscopy (CLSM) observation and the higher cellular uptake of drug for DOX/FBP NPs over naked DOX was observed. The prepared FBP NPs had the potential to be used as a powerful carrier to target anticancer drugs to folate-receptor-expressing tumor cells and reduce cytotoxicity to normal tissues

Environmental impact assessments of the Three Gorges Project in China: issues and interventions

The paper takes China's authoritative Environmental Impact Statement for the Yangzi (Yangtze) Three Gorges Project (TGP) in 1992 as a benchmark against which to evaluate emerging major environmental outcomes since the initial impoundment of the Three Gorges reservoir in 2003. The paper particularly examines five crucial environmental aspects and associated causal factors. The five domains include human resettlement and the carrying capacity of local environments (especially land), water quality, reservoir sedimentation and downstream riverbed erosion, soil erosion, and seismic activity and geological hazards. Lessons from the environmental impact assessments of the TGP are: (1) hydro project planning needs to take place at a broader scale, and a strategic environmental assessment at a broader scale is necessary in advance of individual environmental impact assessments; (2) national policy and planning adjustments need to react quickly to the impact changes of large projects; (3) long-term environmental monitoring systems and joint operations with other large projects in the upstream areas of a river basin should be established, and the cross-impacts of climate change on projects and possible impacts of projects on regional or local climate considered. © 2013 Elsevier B.V.Xibao Xu, Yan Tan, Guishan Yan

Determination of trace copper in water samples by flame atomic absorption spectrometry after preconcentration on a phosphoric acid functionalized cotton chelator

This paper reports the preparation of a phosphorylated cotton chelator (PCC) by solid phase esterification of phosphoric acid (PA) onto defatted cotton fibres using urea as the catalyst. The synthesized PCC was employed for the preconcentration of copper from water samples prior to its determination by flame atomic absorption spectrometry (FAAS). The preconcentration of copper was studied under both batch and column techniques. The pH range for the quantitative preconcentration of copper was 4.0–7.0. The sorption time required for each sample was less than 30 min by the batch method. The copper sorption capacity of the PCC was found to be 15.3 mg/g at the optimum pH value. Elution with 1.0 mol dm-3 hydrochloric acid was found to be quantitative. Feasible flow rates of the copper solution for quantitative sorption onto the column packed with PCC were 0.5–4.0 ml min-1, whereas the optimum flow rate of the hydrochloric acid solution for desorption was less than 1.5 ml min-1. An 80-fold preconcentration factor could be achieved under the optimum column conditions. The tolerance limits for common metal ions on the preconcentration of copper and the number of times of column reuse were investigated. The proposed method was successfully applied for the preconcentration and determination of trace copper in natural and drinking water samples by FAAS