Controlled synthesis of (CuO-Cu2O)Cu/ZnO multi oxide nanocomposites by facile combustion route: A potential photocatalytic,antimicrobial and anticancer activity

Photocatalytic activity of (CuO-Cu₂O)Cu/ZnO hetero-junction nanocomposites along with their luminescent, biological applications in the progress of anticancer and antibacterial agents is investigated. The Cu and Zn bi-components modified (CuO-Cu₂O)Cu/ZnO nanocomposites were synthesized via facile combustion route in the presence of controlled fuel to oxidizer ratio and were characterized by X-Ray Diffraction (XRD) patterns, Transmission electron microscopy (TEM), High resolution Transmission electron microscopy (HRTEM), Scanning Electron Microscopy (SEM), X-ray photoelectron Spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), photoluminescence (PL) and energy dispersive X-ray (EDX) analysis. The PL and UV–Visible diffused reflectance spectral (UV–Vis-DRS) techniques were used to measure the optical sensitivity and tuning of band gap in the samples. The excellent photocatalytic degradation of Methylene Blue and industrial waste water under Sunlight irradiation depends on the mass ratios of Cu/Zn. The findings show that the addition of a certain proportion of CuO, Cu₂O, ZnO, and Cu can promote efficiency in Sunlight harvesting and separation of charge carriers. Process parameters namely catalyst quantity, dye concentration and a proposal for the mechanism of degradation pathway, experiments for trapping and enhancer are investigated. The study of photoluminescence, CIE and CCT calculations suggests that the present nanocomposite may find applications as phosphor material in warm white LEDs. The second segment of this study deals with the investigation of antibacterial performance of composites upon Gram-negative and Gram-positive bacteria. The results indicate that nanocomposites can be used in antibacterial control systems and as an important growth inhibitor in various microorganisms. The cytotoxic effect of the (CuO-Cu₂O)Cu/ZnO (CCCZ11) nanocomposite was determined by colorimetric and flow cytometric cell cycle analysis. Our experimental results show that the nanocomposite can induce apoptosis and suppress the proliferation of HeLa cells. The applications of nanocomposites based on Cu, an abundant and inexpensive metal has created much interest in various multifunctional applications.     

L-Selenocystine induce HepG2 cells apoptosis through ROS-mediated signaling pathways

At present, Hepatocarcinoma is one of the main causes of tumor related death all over the world. However, there are still many clinical restrictions on the treatment of liver cancer. Recently, L-Selenocystine has been shown to be a novel treatment for tumors, especially human glioma cells. But, the mechanism of L-Selenocystine against hepatocellular carcinoma remains unclear. Therefore, the main objective of this study was to investigate the effects of L-Selenocystine on HepG2 cell proliferation and activation of reactive oxygen species (ROS) mediated signaling pathway. L-Selenocystine can significantly inhibit HepG2 cell proliferation by activating caspase-3 and cleaving PARP to induce apoptosis. Moreover, the excessive production of ROS and the influence of Bax signaling pathway which can promote cell apoptosis are key factors for L-Selenocystine to induce HepG2 cell apoptosis. Therefore, the date of this study suggest that ROS mediated signal transduction mechanism may provide certain reference significance for L-Selenocystine induced HepG2 cell apoptosis.     

A theoretical study on mechanism of the anticancer drug camptothecin's E-ring-opening

A reaction mechanism of the anticancer agent camptothecin (CPT)’s E-ring-opening has been studied by DFT method and IEF-PCM solvation model. Our results indicate that under the physiological PH, CPT's E-ring-opening is a spontaneous process, and it conforms to the addition coupled elimination reaction pathway with a proton translocation. The obtained activation free energies in the explicit water model are in agreement with the available experimental values. More than ten reactions have been studied to provide exhaustive analyses of the relationship between structure and reactivity. On the whole, our results accord with the experimental findings and the mechanism we proposed is reasonable.     

Macromolecular Antiproliferative Agents Featuring Dicarboxylato-Chelated Platinum

Cancerous diseases, together with cardiac afflictions, account for the predominant causes of death among the adult population of the Western world. The classical platinum drugs, with cisplatin as their parent, have established themselves for years as leading components in the oncologist’s arsenal of antitumor agents. As with most other antineoplastic drugs, however, incisive pharmacological deficiencies, notably excessive systemic toxicity and induction of drug resistance, have severely curtailed their overall efficaciousness. With the objective of overcoming these counterproductive deficiencies, the technique of polymer-drug conjugation, representing an advanced modality of drug delivery, has been developed in recent years to high standards worldwide. In a drug conjugate, water-soluble macromolecular carrier constructs designed in compliance with stringent pharmacological specifications are covalently, yet bioreversibly, interconnected with the bioactive agent. As a macromolecule following a pharmacokinetic pathway different from that of non-polymeric compounds, the conjugate acts as a pro-drug favorably transporting the agent through the various body compartments to, and into, the target cell, where the agent is enzymatically or hydrolytically separated from the carrier for its biological action. In the authors’ laboratories the conjugation strategy has been adopted as the primary tool for drug efficacy enhancement. The present paper describes a special type of platinum complex carrier-bound via dicarboxymetal chelation, synthesized from carboxyl-functionalized polyamide-type carriers by platination with trans-1,2-diaminocyclohexanediaquaplatinum(II) dinitrate. In a series of in vitro tests antiproliferative activities have been determined against several human cancer cell lines. Whereas no improvements are observed in tests against a colorectal cancer, outstanding findings of the screening program include a 10- to 100-fold increase in cell-killing performance of the conjugates relative to the (non-polymeric) cisplatin standard against the HeLa adenocarcinoma, and distinctly reduced resistance factors (again, relative to cisplatin) in tests against the A2780 and A2780-cis pair of ovarian cell lines. These findings augur well for future developments of this class of platinum drugs. This article is dedicated to Professor Astruc.     

Treatment of wastewater containing cytotoxic drugs by CoFe2O4 nanoparticles in Fenton/ozone oxidation process

ABSTRACT

Nano-sized cobalt-substituted magnetite has been synthesized and used as a heterogeneous Fenton catalyst for the removal of anticancer drug Flutamide (FLU) from a solution with a concentration of 150 μM. By using response surface methodology at the optimal conditions of Fenton oxidation (FO) process, 67.7% FLU removal was obtained. In order to increase the removal efficiency of the drug, ozonation was applied in combination with FO process. Maximum FLU removal (93.0%) was obtained using 0.6 g O3 l^?1h^?1 and 163 mg L^?1 of the catalyst. The results indicate that the proposed method is efficient for the degradation of cytotoxic drugs.     

Mechanochemical preparation and anticancer effect of realgar As4S4 nanoparticles

In the past two decades nanocrystalline sulphide semiconductors have attracted considerable interest due to their intriguing properties and structure diversities. Arsenic show interesting solid state phenomena as well as therapeutic effects for various diseases. In this study, the nanosized realgar As₄S₄ particles (d - 144 nm) have been prepared by a high-energy milling. The solid state properties of the nanoparticles milled under various experimental conditions were characterized by XRD method, by measurement of specific surface area and particle size distribution in nanosized region. In biological tests the sensitivity of human cancer cell lines for the realgar nanoparticles has been clearly demonstrated.     

Preclinical anticancer activity of DNA-based cleavage molecules

Deoxyribozymes (DNAzymes) are DNA residue-based molecules capable of specific cleavage of complementary mRNA. As such, they are more stable counterparts for the earlier discovered ribozymes. A handful of studies have shown the potential of DNAzymes against cancer both in cell culture and importantly in vivo models. This relatively new molecular entity may progress to clinical trials provided that more extensive testing is carried out at the preclinical stage. While a significant amount of work has gone into chemically stabilizing the molecule, delivery is one area that needs particular attention.     

Novel modified furanoeremophilane-type sesquiterpenes and benzofuran derivatives from Ligularia veitchiana

Three new compounds, 2-acetyl-5-isopentenyl-6-methylbenzofuran (1), 1,3-dimethoxy-4,6-dimethylnaphthofuran (2), and 3,4,5-trimethoxycinnamyl angelic acid ester (3), along with 13 known compounds were isolated from the roots of Ligularia veitchiana, which are commonly used as a folk medicine and food supplement in China. Their structures were elucidated by spectroscopic techniques. Biological screening studies indicated that compound 2 displayed a moderate activity against Staphylococcus aureus, which may be due to the existence of a modified eremophilane skeleton, whilst compounds 11, 12 and 15 exhibited potent activity against HL-60 and HeLa cell lines.     

利用辐射技术制备慢释放抗癌药及其对小鼠实体肿瘤的治疗效果

本文介绍利用低温过冷态辐射聚合制备慢释放抗癌药的方法。报告这种慢释放氟尿嘧啶药对小鼠实体肿瘤的治疗效果。对于可移植性615小鼠前胃鳞状上皮癌和可移植性昆明小鼠S180肉瘤的抑制率分别为40％和96％,不仅有显著的治疗效果而且用药后毒副作用也有明显降低。     

Quercetin loading on mesoporous magnetic MnFe2O4@ hydroxyapatite core-shell nanoparticles for treating cancer cells

Despite the availability of various nanostructure for cancer cells therapeutic, caring hydrophobic drugs to the target site is still one of the great challenges in chemotherapy. In this study, quercetin (QC), a poorly water-soluble natural anticancer agent, was used as a model drug to evaluate the efficiency of mesoporous magnetic MnFe₂O₄ core-shell nanocomposite particles. A simple co-precipitation method was employed to synthesis MnFe₂O₄ as core of nanostructure. Then, the obtained MnFe₂O₄ nanoparticles were coated with mesoporous hydroxyapatite (HA) shell as a new perspective for drug loading. The magnetic mesoporous nanostructure had specific surface area and mean pore size of 165.44 m²/g and 11.561 nm, respectively. In QC loading process, the MnFe₂O₄@HA nanostructure demonstrated loading capacity of 123 µg/mg with pH-depended release manner. In compare with free QC, loaded QC on MnFe₂O₄ core-shell nanocomposite particles exhibited 55% higher antioxidant activities against free 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. Moreover, comparative in-vitro anticancer studies on Michigan cancer foundation (MCF)-7 cells, breast cancer cell line, demonstrated more reduction in number of viable cells (35.6%) using loaded QC than that of free QC (50.76%), suggesting improvement in the solubility of QC by loading onto mesoporous magnetic nanocomposite particles compared to free QC.