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2.
Cell Signal ; 53: 390-399, 2019 01.
Article in English | MEDLINE | ID: mdl-30448346

ABSTRACT

Actin-like 6A (ACTL6A), a component of BAF chromatin remodeling complexes, is important for cell differentiation. Nevertheless, its role and mechanism in acute promyelocytic leukemia (APL) has not been reported. To identify the genes that may participate in the development of APL, we analyzed data from an APL cDNA microarray (GSE12662) in the NCBI database, and found that ACTL6A was up-regulated in APL patients. Subsequently, we investigated the function and mechanisms of ACTL6A in myeloid cell development. The expression of ACTL6A was gradually decreased during granulocytic differentiation in all-trans retinoic acid-treated NB4 and HL-60 cells, and phorbol myristate acetate-treated HL-60 cells. We also found that knockdown of ACTL6A promoted differentiation in NB4 and HL-60 cells, and decreased the levels of Sox2 and Notch1. Mechanistically, ACTL6A interacted with and was co-localized with Sox2 and p53. Meanwhile, CBL0137, an activator of p53, decreased the expression of ACTL6A and promoted differentiation in NB4 and HL-60 cells. These findings suggest that the inhibition of ACTL6A promotes differentiation via the Sox2 and Notch1 signaling pathways. Furthermore, the differentiation promoted by inhibiting ACTL6A could be regulated by p53 via its physical interaction with ACTL6A.


Subject(s)
Actins/metabolism , Chromosomal Proteins, Non-Histone/metabolism , DNA-Binding Proteins/metabolism , Leukemia, Promyelocytic, Acute/metabolism , Receptor, Notch1/metabolism , SOXB1 Transcription Factors/metabolism , Tumor Suppressor Protein p53/metabolism , Cell Line, Tumor , HL-60 Cells , Humans , Protein Interaction Maps , Signal Transduction
3.
J Air Waste Manag Assoc ; 62(9): 1012-21, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23019815

ABSTRACT

UNLABELLED: Experimental studies on desulfurization and denitrification were carried out using activated carbon irradiated by microwave. The influences of the concentrations of nitric oxide (NO) and sulfur dioxide (SO2), the flue gas coexisting compositions, on adsorption properties of activated carbon and efficiencies of desulfurization and denitrification were investigated. The results show that adsorption capacity and removal efficiency of NO decrease with the increasing of SO2 concentrations in flue gas; adsorption capacity of NO increases slightly first and drops to 12.79 mg/g, and desulfurization efficiency descends with the increasing SO2 concentrations. Adsorption capacity of SO2 declines with the increasing of O2 content in flue gas, but adsorption capacity of NO increases, and removal efficiencies of NO and SO2 could be larger than 99%. Adsorption capacity of NO declines with the increase of moisture in the flue gas, but adsorption capacity of SO2 increases and removal efficiencies of NO and SO2 would be relatively stable. Adsorption capacities of both NO and SO2 decrease with the increasing of CO2 content; efficiencies of desulfurization and denitrification augment at the beginning stage, then start to fall when CO2 content exceeds 12.4%. The mechanisms of this process are also discussed. IMPLICATIONS: The prominent SO2 and NOx treatment techniques in power plants are wet flue gas desulfurization (FGD) and the catalytic decomposition method like selective catalytic reduction (SCR) or nonselective catalytic reduction (NSCR). However, these processes would have some difficulties in commercial application due to their high investment, requirement of expensive catalysts and large-scale equipment, and so on. A simple SO2 and NOx reduction utilizing decomposition by microwave energy method can be used. The pollutants control of flue gas in the power plants by the method of microwave-induced decomposition using adsorption of activated carbon/microwave desorption can meet the requirements of environmental protection, which will be stricter in the future.


Subject(s)
Air Pollutants/isolation & purification , Nitrogen Oxides/isolation & purification , Sulfur Dioxide/isolation & purification , Adsorption , Air Pollutants/radiation effects , Charcoal/chemistry , Denitrification , Hot Temperature , Microwaves , Nitrogen Oxides/radiation effects , Oxygen/chemistry , Sulfur Dioxide/radiation effects , Water/chemistry
4.
Environ Technol ; 33(13-15): 1811-7, 2012.
Article in English | MEDLINE | ID: mdl-22988643

ABSTRACT

Experimental studies were carried out on flue gas denitrification using activated carbon irradiated by microwave. The effects of microwave irradiation power (reaction temperature), the flow rate of flue gas, the concentration of NO and the flue gas coexisting compositions on the adsorption property of activated carbon and denitrification efficiency were investigated. The results show that: the higher of microwave power, the higher of denitrification efficiency; denitrification efficiency would be greater than 99% and adsorption capacity of NO is relatively stable after seven times regeneration if the microwave power is more than 420 W; adsorption capacity of NO in activated carbon bed is 33.24 mg/g when the space velocity reaches 980 per hour; adsorption capacity declines with increasing of the flow rate of flue gas; the change in denitrification efficiency is not obvious with increasing oxygen content in the flue gas; and the maximum adsorption capacity of NO was observed when moisture in flue gas was about 5.88%. However, the removal efficiency of NO reduces with increasing moisture, and adsorption capacity and removal efficiency of NO reduce with increasing of SO2 concentration in the flue gas.


Subject(s)
Air Pollutants/isolation & purification , Charcoal , Microwaves , Nitrogen Oxides/isolation & purification , Adsorption , Air Pollution/prevention & control , Denitrification , Equipment Design , Gases , Sulfur Dioxide , Water
5.
Environ Technol ; 33(10-12): 1225-30, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22856293

ABSTRACT

This paper describes the research background and chemistry of desulfurization and denitrification technology using microwave irradiation. Microwave-induced catalysis combined with activated carbon adsorption and reduction can reduce nitric oxide to nitrogen and sulfur dioxide to sulfur from flue gas effectively. This paper also highlights the main drawbacks of this technology and discusses future development trends. It is reported that the removal of sulfur dioxide and nitric oxide using microwave irradiation has broad prospects for development in the field of air pollution control.


Subject(s)
Air Pollution/prevention & control , Denitrification , Microwaves , Waste Management/methods
6.
Water Res ; 45(18): 5886-94, 2011 Nov 15.
Article in English | MEDLINE | ID: mdl-21962849

ABSTRACT

The sonolytic degradation of aqueous solutions of dimethoate, O,O-dimethyl S-[2-(methylamino)-2-oxoethyl]dithiophosphate, was examined. Optimal degradation rates were obtained at 619 kHz for continuous sonolysis and 406 kHz for pulse sonolysis. The primary pathways for degradation include hydroxyl radical oxidation, hydrolysis and pyrolysis on collapsing cavitation bubble interfaces. Reaction mechanisms coupled with the corresponding kinetic models are proposed to reproduce the observed concentration versus time profiles for dimethoate, omethoate and N-(methyl) mercaptoacetamide during sonolysis. The oxidation and hydrolysis of dimethoate and omethoate occurred at the water-bubble interface was the rate-determining step for sonolytic overall degradation of dimethoate. More than 90% toxicity of dimethoate was reduced within 45 min ultrasonic irradiation. Ferrous ion at micro molar level can significantly enhance the sonolytic degradation of dimethoate and effectively reduce the yields of toxic intermediate omethoate.


Subject(s)
Dimethoate/chemistry , Dimethoate/toxicity , Sonication/methods , Acetamides/chemistry , Electrons , Gas Chromatography-Mass Spectrometry , Kinetics , Least-Squares Analysis , Models, Chemical , Nonlinear Dynamics , Time Factors , Ultrasonics
7.
Huan Jing Ke Xue ; 31(2): 324-30, 2010 Feb.
Article in Chinese | MEDLINE | ID: mdl-20391697

ABSTRACT

Based on the conventional water treatment processes widely used in China, a pilot scale study was performed to investigate emergent treatment for arsenite pollution in water source. The results show that As removal efficiency can only reach to 71.85% by conventional water treatment process. The removal efficiencies of dissolved arsenic and total arsenic by mixing, first flocculation, second flocculation, sedimentation, filtration units were 36.00%, 5.42%, 9.30%, 14.95%, 7.88% and 9.10%, -3.62%, 2.74%, 55.12%, 8.51% respectively, when the concentration of As(III) in raw water was 150 microg/L. The arsenic concentration in treated water can not be effectively controlled below 10 microg/L. Hence, the pre-oxidation is necessary. The pre-chlorination-enhanced coagulation process can effectively deal with the sudden As(III) pollution. But for lower chlorine dosage, both ammonia concentration and different pre-chlorination sites have significant effects on arsenic removal, which should be taken into account. Potassium permanganate pre-oxidation-enhanced coagulation process can be more effectively deal with the sudden As(III) pollution than pre-chlorination. Moreover the different pre-oxidation sites have no obvious effect on arsenic removal. As a result, potassium permanganate is recommended as an oxidant for As(III).


Subject(s)
Arsenic/isolation & purification , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Water Supply/analysis , Arsenic/analysis , Fresh Water , Pilot Projects , Water Pollutants, Chemical/analysis
8.
Ultrason Sonochem ; 17(5): 802-9, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20303819

ABSTRACT

Ultrasonic degradation of parathion has been investigated in this study. At a neutral condition, 99.7% of 2.9 microM parathion could be decomposed within 30 min under 600 kHz ultrasonic irradiation at ultrasonic intensity of 0.69 W/cm(2). The degradation rate increased proportionally with the increasing ultrasonic intensity from 0.10 to 0.69 W/cm(2). The parathion degradation was enhanced in the presence of dissolved oxygen due to formation of more ()OH, but was inhibited in the presence of nitrogen gas owning to the free radical scavenging effect in vapor phase within the cavitational bubbles. CO(3)(2-), HCO(3)(-), and Cl(-) exhibited the inhibiting effects on parathion degradation, and their inhibition degrees followed the order of CO(3)(2-)>HCO(3)(-)>Cl(-). But Br(-) had a promoting effect on parathion degradation, and the effect increased with the increasing Br(-) level. Moreover, both the hydrophobic and hydrophilic natural organic matters (NOM) could slow the parathion degradation, but the inhibiting effect caused by hydrophobic component was greater, especially the strongly hydrophobic NOM. The three reaction pathways of parathion sonolysis were proposed, including formation of paraoxon, formation of 4-nitrophenol, and unknown species products. The kinetics tests showed that anyone of these pathways could not be overlooked, and the fractions of the parathion decomposed in the three pathways were 28.19%, 32.92% and 38.89%, respectively. In addition, 66.61% of paraoxon produced was degraded into 4-nitrophenol. Finally, kinetics models were established to adequately predict the concentrations of parathion, paraoxon and 4-nitrophenol as a function of time.


Subject(s)
Parathion/chemistry , Parathion/radiation effects , Sonication , Water Pollutants/chemistry , Water Pollutants/radiation effects , Water Purification/methods , Water/chemistry , Parathion/isolation & purification , Water Pollutants/isolation & purification
9.
J Hazard Mater ; 175(1-3): 138-45, 2010 Mar 15.
Article in English | MEDLINE | ID: mdl-19854573

ABSTRACT

The parathion degradation under ultrasonic irradiation in aqueous solution was investigated. The results indicate that at the conditions in question, degradation rate of parathion decreased with increasing initial concentration and decreasing power. The optimal frequency for parathion degradation was 600 kHz. The free radical reactions predominate in the sonochemical degradation of parathion and the reaction zones are predominately at the bubble interface and, to a much lesser extent, in bulk solution. The gas/liquid interfacial regions are the real effective reaction sites for sonochemical degradation of parathion. The reaction can be well described as a gas/liquid heterogeneous reaction which obeys a kinetic model based on Langmuir-Hinshelwood model. The main pathways of parathion degradation by ultrasonic irradiation were also proposed by qualitative and quantitative analysis of organic and inorganic byproducts. It is indicated that the N(2) in air takes part in the parathion degradation through the formation of NO(2) under ultrasonic irradiation. Parathion is decomposed into paraoxon and 4-nitrophenol in the first step via two different pathways, respectively, which is in agreement with the theoretical molecular orbital (MO) calculations.


Subject(s)
Chemistry/methods , Parathion/chemistry , Ultrasonics , Water Purification/methods , Free Radical Scavengers , Free Radicals , Gases , Hydroxyl Radical , Kinetics , Models, Chemical , Nitrogen/chemistry , Nitrophenols/chemistry , Paraoxon/chemistry , Sonication , Water Pollutants, Chemical/analysis
10.
Huan Jing Ke Xue ; 30(6): 1663-8, 2009 Jun 15.
Article in Chinese | MEDLINE | ID: mdl-19662848

ABSTRACT

The pilot and bench scale studies on pentavalent arsenic removal by coagulation and the strengthening effect of flocs recycling were performed. The results show that above 95% As (V) in the raw water exists in the form of dissolved As (V). Furthermore, the removal efficiencies of dissolved arsenic and total arsenic by mixing, first flocculation, second flocculation, sedimentation, filtration units were 87.92%, 6.18%, 2.38%, 1.55%, 1.23% and 1.10%, 1.83%, 2.20%, 86.42%, 7.38% respectively. Therefore, conversion rate of dissolved As(V) into particulate As(V) and the settlement performance of flocs were strongly dependent on the coagulation effect, which determined the As(V) removal efficiency in the whole system. Flocs have a strong adsorption capacity for As(V) and the adsorption obeys a second order reaction kinetics and well fits the modified Freundlich model. Flocs recycling can obviously promoted the As(V) removal by enhanced coagulation and reduce the dosage of coagulant with recycling point set at rapid mixed site and recycling ratio at 50%.


Subject(s)
Arsenic/isolation & purification , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Water Supply/analysis , Adsorption , Flocculation , Pilot Projects , Water Pollutants, Chemical/analysis
11.
Huan Jing Ke Xue ; 29(9): 2493-500, 2008 Sep.
Article in Chinese | MEDLINE | ID: mdl-19068632

ABSTRACT

Emergent treatment of source water polluted by representative herbicide molinate and ametryn was researched. The results indicate that activated carbon adsorption and prechlorination could achieve high efficiencies to remove the herbicides. The pseudo second-order adsorption kinetic model and Freundlich adsorption isotherm model can be used to describe the adsorption process and the adsorption equilibrium of molinate and ametryn adsorbed by powdered activated carbon (PAC) in raw water respectively. Either molinate or ametryn of about 200 microg/L in water could be completely removed by 40 mg/L PAC. The best PAC adding point was 20 min before coagulation. The two herbicides were easily removed by granular activated carbon (GAC) column (20 cm high) which can be the available supplement of PAC treatment to strengthen safety. The Cl2 dosage of 2.5 mg/L could oxidize the two herbicides completely, but the chlorination products as well as their toxicity need further study. PAC adsorption combined with 1 mg/L KMnO4 preoxidation didn't improve the removal efficiencies of molinate and ametryn. The effect of PAC adsorption combined with 1.5 mg/L prechlorination depends on their adding sequence. When source water was simultaneously contaminated by the two herbicides both about 200 microg/L, the PAC and Cl2 dosage have to be increased to 50 mg/L and 3 mg/L respectively, then both herbicides can be removed or oxidized fully.


Subject(s)
Azepines/chemistry , Charcoal/chemistry , Thiocarbamates/chemistry , Triazines/chemistry , Water Pollutants, Chemical/chemistry , Adsorption , Herbicides/chemistry , Oxidation-Reduction , Water Pollution/prevention & control , Water Purification/methods
12.
Huan Jing Ke Xue ; 29(10): 2841-5, 2008 Oct.
Article in Chinese | MEDLINE | ID: mdl-19143382

ABSTRACT

Based on two common coagulants-polyferric sulfate (PFS) and polyaluminum chloride (PACl), some measurements and processes in the background of Pb (II) concentration sudden increase in water were studied. The removal efficiency of Pb(II) was compared between PAC and diatomite absorption with coagulation. The effect of coagulant dosage, initial concentration of Pb(II), pH value and KMnO4 preoxidation on coagulation were investigated. The results showed that using PFS was better than PACl for the removal of Pb(II). The regulating pH value up to 9 could improve the removal efficiency of Pb(II) up to 95% by coagulation under the optimum dosage of coagulant PFS of 10 mg/L. KMnO4 preoxidation could improve the removal efficacy of Pb(II) by coagulation of PACl only. The Pb(II) removal efficiency of PAC and diatomite absorption with coagulation were almost equal. Pb(II) concentration could be lowered from 402 microg/L to below 10 microg/L under the condition that dosages of PAC or diatomite were 10 mg/L or 25 mg/L by using PFS. The same effect could be got under the condition that dosages of PAC or diatomite were 20 mg/L or 50 mg/L by using PACl. KMnO4 and diatomite are dosed at the same time would weaken their function each other. Therefore, diatomite adsorption coupled with coagulation is the simplest and most effective method for removing Pb(II).


Subject(s)
Lead/analysis , Water Pollutants, Chemical/analysis , Water Purification/methods , Water Supply/analysis , Adsorption , Aluminum Chloride , Aluminum Compounds/chemistry , Chlorides/chemistry , Coagulants/chemistry , Diatomaceous Earth/chemistry , Ferric Compounds/chemistry , Water Pollution/prevention & control
13.
J Environ Sci (China) ; 19(5): 536-9, 2007.
Article in English | MEDLINE | ID: mdl-17915681

ABSTRACT

In recent years, membrane ultrafiltration (UF) of surface water for drinking water treatment has become a more attractive technology worldwide as a possible alternative treatment to conventional clarification. To evaluate the performance of ultrafiltration membranes for treatment of surface water in North China, a 48-m2 low pressure hollow fiber membrane ultrafiltration pilot plant was constructed. Ultrafiltration was operated in cross-flow and with powdered activated carbon (PAC) adsorption. Turbidity was almost completely removed to less than 0.2 NTU (below Chinese standard 1 NTU). It was found that PAC addition enhanced organic matter removal. The combined process of PAC/UF allowed to 41% removal of COD(Mn), 46% removal of DOC and 57% decrease in UV254 absorbance. The elimination of particles, from average 12000/ml in the raw water to approximately 15/ml in the permeated, was observed. When PAC concentration was below 30 mg/L, backwashing could recovery the membrane flux with backwash interval/backwashing duration of 1/30.


Subject(s)
Carbon/chemistry , Membranes, Artificial , Polyvinyl Chloride , Water Pollutants/chemistry , Water Purification/methods , Adsorption , China , Nephelometry and Turbidimetry , Pilot Projects , Rivers , Ultrafiltration , Water Supply
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