78 research outputs found
Ligustrazine Inhibits the Migration and Invasion of Renal Cell Carcinoma
Ligustrazine is a Chinese herb (Chuanxiong) approved for use as a medical drug in China. Recent evidence suggests that ligustrazine has promising antitumor properties. Our preliminary results showed that ligustrazine could inhibit the growth of human renal cell carcinoma (RCC) cell lines. However, the complicated molecular mechanism has not been fully revealed. Therefore, the purpose of this study to investigate the mechanism of ligustrazine resistance in human RCC cells. Cell proliferation, migration, invasion, and colony-formation ability of RCC cells A498 were detected by MTT assay, clonal formation rates, and transwell chamber assay in vitro. The expression of epithelial–mesenchymal transition (EMT)–related proteins were analyzed using western blot test. The effect of ligustrazine on the growth of A498 cells in nude mice was investigated in vivo. Our results showed that ligustrazine could significantly inhibit the proliferation, migration, and invasion of A498 both in vivo and vitro. Western blot analysis showed that the expressions of EMT-related, N-cadherin, snail, and slug proteins were significantly decreased in A498 in the ligustrazine treatment group. This study indicated that ligustrazine could significantly inhibit the malignant biological behaviors of RCC cell lines, possibly by inhibiting the EMT process
Ligustrazine Inhibits the Migration and Invasion of Renal Cell Carcinoma
Ligustrazine is a Chinese herb (Chuanxiong) approved for use as a medical drug in China. Recent evidence suggests that ligustrazine has promising antitumor properties. Our preliminary results showed that ligustrazine could inhibit the growth of human renal cell carcinoma (RCC) cell lines. However, the complicated molecular mechanism has not been fully revealed. Therefore, the purpose of this study to investigate the mechanism of ligustrazine resistance in human RCC cells. Cell proliferation, migration, invasion, and colony-formation ability of RCC cells A498 were detected by MTT assay, clonal formation rates, and transwell chamber assay in vitro. The expression of epithelial–mesenchymal transition (EMT)–related proteins were analyzed using western blot test. The effect of ligustrazine on the growth of A498 cells in nude mice was investigated in vivo. Our results showed that ligustrazine could significantly inhibit the proliferation, migration, and invasion of A498 both in vivo and vitro. Western blot analysis showed that the expressions of EMT-related, N-cadherin, snail, and slug proteins were significantly decreased in A498 in the ligustrazine treatment group. This study indicated that ligustrazine could significantly inhibit the malignant biological behaviors of RCC cell lines, possibly by inhibiting the EMT process
Recent advance on VOCs oxidation over layered double hydroxides derived mixed metal oxides
Catalytic oxidation is regarded as one of the most promising strategies for volatile organic compounds (VOCs) purification. Mixed metal oxides (MMOs), after topological transformation using layered double hydroxides (LDHs) as precursors, are extensively used as catalysts for VOCs oxidation due to their uniformity advantage. This review summarizes the developments in the LDH-derived VOCs heterogeneous catalytic oxidation over the last 10 years. Particularly, it addresses the VOCs abatement performance over MMO, noble metal/MMO, core-shell structured MMO, and integral MMO film catalysts originating from LDHs. Moreover, it highlights the water vapor effect and oxidation mechanism. This review indicates that LDH-based catalysts are a category of important VOCs oxidation materials. (C) 2020, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved
Recent advance on VOCs oxidation over layered double hydroxides derived mixed metal oxides
Catalytic oxidation is regarded as one of the most promising strategies for volatile organic compounds (VOCs) purification. Mixed metal oxides (MMOs), after topological transformation using layered double hydroxides (LDHs) as precursors, are extensively used as catalysts for VOCs oxidation due to their uniformity advantage. This review summarizes the developments in the LDH-derived VOCs heterogeneous catalytic oxidation over the last 10 years. Particularly, it addresses the VOCs abatement performance over MMO, noble metal/MMO, core-shell structured MMO, and integral MMO film catalysts originating from LDHs. Moreover, it highlights the water vapor effect and oxidation mechanism. This review indicates that LDH-based catalysts are a category of important VOCs oxidation materials. (C) 2020, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved
In vitro and in vivo low-dose exposure of simulated cooking oil fumes to assess adverse biological effects
Cooking oil fumes (COFs) represent a major indoor environmental pollutant and exhibit potent mutagenic or carcinogenic health effects caused by containing various heterocyclic aromatic amines (HAAs) and long-chain aldehydes. Despite some evaluation of the cumulative exposure of COFs to cancer cells under high concentration were evaluated, their biological adverse effects with low-dose exposure to healthy cells had been inadequately investigated. Herein, we firstly scrutinized the three selected typically toxic compounds of heterocyclic amine 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 3,8-dimethylammidazo[4,5-f]quinoxalin-2-amine (MeIQx) and trans, trans-2,4-decadienal (TDA)) emitted from COFs. In vitro studies revealed that the PhIP, MeIQx and TDA aerosol particles were negligible toxicity to cancer cells (A549 and HepG-2) but strong cytotoxicity to normal healthy cells (HelF and L02) under 0.5-4 mu g/mL low dose exposure based on the reactive oxygen species (ROS) mechanism. In vivo studies demonstrated that PhIP caused significant lung and liver damage after exposure to PhIP for 30 days with mice. These results indicated the direct proof of healthy cell damage even at low-dose exposure to HAAs and aldehydes
Magnetic porous Fe3O4/carbon octahedra derived from iron-based metal-organic framework as heterogeneous Fenton-like catalyst
The synthesis of effective and recyclable Fenton-like catalyst is still a key factor for advanced oxidation processes. Herein, magnetic porous Fe3O4/carbon octahedra were constructed by a two-step controlled calcination of iron-based metal organic framework. The porous octahedra were assembled by interpenetrated Fe3O4 nanoparticles coated with graphitic carbon layer, offering abundant mesoporous channels for the solid-liquid contact. Moreover, the oxygen-containing functional groups on the surface of graphitic carbon endow the catalysts with hydrophilic nature and well-dispersion into water. The porous Fe3O4/carbon octahedra show efficiently heterogeneous Fenton-like reactions for decomposing the organic dye methylene blue (MB) with the help of H2O2, and nearly 100% removal efficiency within 60 min. Furthermore, the magnetic catalyst retains the activity after ten cycles and can be easily separated by external magnetic field, indicating the long-term catalytic durability and recyclability. The good Fenton-like catalytic performance of the as-synthesized Fe3O4/carbon octahedra is ascribed to the unique mesoporous structure derived from MOF-framework, as well as the sacrificial role and stabilizing effect of graphitic carbon layer. This work provides a facile strategy for the controllable synthesis of integrated porous octahedral structure with graphitic carbon layer, and thereby the catalyst holds significant potential for wastewater treatment. (C) 2017 Elsevier B.V. All rights reserved.</p
A reversible pH-modified fluorescence transition in block copolymer micelles enwrapped with a zinc(II) fluorescent complex
A reversible pH-modified blue to green luminescent transition systemwas constructed by encapsulating bis(2-(2-hydroxyphenyl)benzothiazolate) zinc (Zn(BTZ)(2)) within poly(styrene-b-acrylic acid) (PS-b-PAA) micelles. The system can respond to changes in the external pH environment from alkaline (7.0-10.5) to weakly acidic (4.5-7.0) conditions, which are absent for the pristine Zn(BTZ)(2) dimethylformamide solution state, and designated as blue and green micelles, respectively. The tunable pH-modified luminescent behavior probably originates from changes in the Zn(BTZ)(2) molecular packing modes modified by the shrink/swell morphology transition of the copolymer micelles due to the reversible ionization of the carboxylic group. The emission transition from blue to green can be further detected through affecting the Zn(BTZ)(2) intermolecular interactions upon grinding the Zn(BTZ)(2) powder. The micelles were further fabricated to form films by electrostatic layer-by-layer assembly with positively charged layered double hydroxide (LDH) nanosheets, which are responsive to acidic and alkaline atmospheres and show higher UV resistance compared to the micelles/PDDA (poly(dimethyldiallylammonium) chloride) film
Catal. Commun.
Mn-Co mixed oxide nanorod with porous structure and high surface area was fabricated by an oxalate route and further used for deep oxidation of VOCs. Compared to the single MnOx or Co3O4, the Mn-Co mixed oxide showed an enhanced activity for ethyl acetate and n-hexane oxidation with T-90% was low to 194 and 210 degrees C at a high space velocity, respectively. The formation of solid solution with spinel structure inhibits the growth of nanoparticles which leads to its higher surface area, and the strong synergistic effect of Mn-Co species in the oxide makes a great contribution to its low temperature reducibility which plays a key role in VOCs' oxidation. (C) 2014 Elsevier B.V. All rights reserved.Mn-Co mixed oxide nanorod with porous structure and high surface area was fabricated by an oxalate route and further used for deep oxidation of VOCs. Compared to the single MnOx or Co3O4, the Mn-Co mixed oxide showed an enhanced activity for ethyl acetate and n-hexane oxidation with T-90% was low to 194 and 210 degrees C at a high space velocity, respectively. The formation of solid solution with spinel structure inhibits the growth of nanoparticles which leads to its higher surface area, and the strong synergistic effect of Mn-Co species in the oxide makes a great contribution to its low temperature reducibility which plays a key role in VOCs' oxidation. (C) 2014 Elsevier B.V. All rights reserved
Excellent low temperature performance for total benzene oxidation over mesoporous CoMnAl composited oxides from hydrotalcites
Mesoporous CoMnAl mixed metal oxide catalysts with various Co/Mn atomic ratios have been obtained by calcination at 450 degrees C of layered double hydroxide (LDH) precursors prepared by the NH4OH co-precipitation-hydrothermal method without distinct MnCO3 peaks. The catalysts exhibited high efficiency for total oxidation of volatile organic compounds (VOCs). The physicochemical properties of the catalysts were characterized using several analytical techniques. Among them, CoMn2AlO shows the optimal activity and the temperature required to achieve a benzene conversion of 90% (T-90) was about 238 degrees C, with a reaction rate and activity energy (E-a) of 0.24 mmol g(cat)(-1) h(-1) and 65.77 kJ mol(-1) respectively. This temperature was 47 degrees C lower than that on the Co3AlO sample with a tower reaction rate of 0.19 mmol g(cat)(-1) h(-1) and a higher E-a 130.31 kJ mol(-1) at a high space velocity (SV = 60 000 mL g(-1) h(-1)). The effects of calcination temperature on the textural properties and catalytic activity of the CoMn2AlO catalyst were further investigated. The as-prepared CoMn2AlO-550 sample displayed superior catalytic activity, with T-90 at 208 degrees C, compared CoMn2AlO-450. The formation of a solid solution with high surface area, rich oxygen vacancies, high Mn4+/Mn3+ and Co3+/Co2+ ratios and low-temperature reducibility made a great contribution to the significant improvement of the catalytic activity
In vitro and in vivo low-dose exposure of simulated cooking oil fumes to assess adverse biological effects
Cooking oil fumes (COFs) represent a major indoor environmental pollutant and exhibit potent mutagenic or carcinogenic health effects caused by containing various heterocyclic aromatic amines (HAAs) and long-chain aldehydes. Despite some evaluation of the cumulative exposure of COFs to cancer cells under high concentration were evaluated, their biological adverse effects with low-dose exposure to healthy cells had been inadequately investigated. Herein, we firstly scrutinized the three selected typically toxic compounds of heterocyclic amine 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 3,8-dimethylammidazo[4,5-f]quinoxalin-2-amine (MeIQx) and trans, trans-2,4-decadienal (TDA)) emitted from COFs. In vitro studies revealed that the PhIP, MeIQx and TDA aerosol particles were negligible toxicity to cancer cells (A549 and HepG-2) but strong cytotoxicity to normal healthy cells (HelF and L02) under 0.5-4 mu g/mL low dose exposure based on the reactive oxygen species (ROS) mechanism. In vivo studies demonstrated that PhIP caused significant lung and liver damage after exposure to PhIP for 30 days with mice. These results indicated the direct proof of healthy cell damage even at low-dose exposure to HAAs and aldehydes
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