In this study, arsenic trioxide(ATO) was encapsulated in liposomes via copper acetate(Cu(OAc)2) gradients and high entrapment efficiency of over 80% was obtained. The average particle size and the zeta-potential of th...In this study, arsenic trioxide(ATO) was encapsulated in liposomes via copper acetate(Cu(OAc)2) gradients and high entrapment efficiency of over 80% was obtained. The average particle size and the zeta-potential of the liposomes were detected to be 115.1 ± 29.1 nm and-21.97 ± 0.6 m V, respectively. The TEM images showed rod-like precipitates in the inner aqueous phase, which was supposed be due to the formation of insoluble ATO–Cu complex.The in vitro drug release of ATO–Cu liposomes exhibited a sustained release over 72 h, and the release rates decreased with the increase of the p H of release media. Pharmacokinetic and tissue distribution studies of ATO liposomes showed significantly reduced plasma clearance rate, increased AUC0–12h and T1/2, and improved tumor distribution of As compared to iv administration of ATO solution. The anti-tumor effect of ATO loaded liposomes to S180 tumor-bearing mice was significantly improved with a tumor inhibition rate of 61.2%,meanwhile the toxicity of encapsulated ATO was greatly decreased. In conclusion, ATO can be effectively encapsulated into liposomes by remote loading method via Cu(OAc)2 gradients;the co-administration of ATO and Cu(Ⅱ) via liposomal formulation may find wide applications in the treatment of various tumors.展开更多
Background:Interest in the use of natural feed additives as an alternative to antimicrobials in the poultry industry has increased in recent years because of the risk of bacterial resistance.One of the most studied gr...Background:Interest in the use of natural feed additives as an alternative to antimicrobials in the poultry industry has increased in recent years because of the risk of bacterial resistance.One of the most studied groups are polyphenolic compounds,given their advantages over other types of additives and their easy potentiation of effects when complexes are formed with metal ions.Therefore,the objective of the present study was to evaluate the impact of dietary supplementation of copper acetate(CA),curcumin(CR),and their combination(CA-CR)against Salmonella Typhimurium colonization,intestinal permeability,and cecal microbiota composition in broiler chickens through a laboratory Salmonella infection model.S.Typhimurium recovery was determined on day 10 post-challenge by isolating Salmonella in homogenates of the right cecal tonsil(12 chickens per group)on Xylose Lysine Tergitol-4(XLT-4)with novobiocin and nalidixic acid.Intestinal integrity was indirectly determined by the fluorometric measurement of fluorescein isothiocyanate dextran(FITC-d)in serum samples from blood obtained on d 10 post-S.Typhimurium challenge.Finally,microbiota analysis was performed using the content of the left caecal tonsil of 5 chickens per group by sequencing V4 region of 16S rRNA gene.Results:The results showed that in two independent studies,all experimental treatments were able to significantly reduce the S.Typhimurium colonization in cecal tonsils(CT,P<0.0001)compared to the positive control(PC)group.However,only CA-CR was the most effective treatment in reducing S.Typhimurium counts in both independent studies.Furthermore,the serum fluorescein isothiocyanate dextran(FITC-d)concentration in chickens treated with CR was significantly lower when compared to PC(P=0.0084),which is related to a decrease in intestinal permeability and therefore intestinal integrity.The effect of dietary treatments in reducing Salmonella was further supported by the analysis of 16S rRNA gene sequences using Linear discriminant analysis effect size(LEfSe)since Salmonella was significantly enriched in PC group(LDA score>2.0 and P<0.05)compared to other groups.In addition,Coprobacillus,Eubacterium,and Clostridium were significantly higher in the PC group compared to other treatment groups.On the contrary,Fecalibacterium and Enterococcus in CR,unknown genus of Erysipelotrichaceae at CA-CR,and unknown genus of Lachnospiraceae at CA were significantly more abundant respectively.Conclusions:CR treatment was the most effective treatment to reduce S.Typhimurium intestinal colonization and maintain better intestinal homeostasis which might be achieved through modulation of cecal microbiota.展开更多
This paper addressed the efect of copper acetate on the combustion characteristics of anthracite depending on the fractional composition of fuel and additive introduction method.Anthracite was impregnated with 5 wt%of...This paper addressed the efect of copper acetate on the combustion characteristics of anthracite depending on the fractional composition of fuel and additive introduction method.Anthracite was impregnated with 5 wt%of Cu(CH_(3)COO)_(2)by mechanical mixing and incipient wetness impregnation.Four anthracite samples of diferent fraction with d<0.1 mm,d=0.1-0.5 mm,d=0.5-1.0 mm,and d=1.0-2.0 mm were compared.According to EDX mapping,incipient wetness impregnation provides a higher dispersion of the additive and its uniform distribution in the sample.The ignition and combustion characteristics of the modifed anthracite samples were studied by thermal analysis and high-speed video recording of the processes in a combustion chamber(at heating medium temperature of 800℃).It was found that copper acetate increases anthracite reactivity,which was evidenced by decreased onset temperature of combustion(ΔT_(i))by 35-190℃and reduced ignition delay time(Δτ_(i))by 2.1-5.4 s.Copper acetate reduces fuel underburning(on average by 70%)in the ash residue of anthracite and decreases the amount of CO and NO_(x)in gas-phase products(on average by 18.5%and 20.8%,respectively).The mechanism for activation of anthracite combustion by copper acetate is proposed.展开更多
olid state reactions of o-aminobenzoic acid (HOAB) with Cu (OAc)_2·H_2O,Cu(HCOO)_2 · 4H_2O, anhydrous Cu (OAc)_2 and Cu (HCOO)_2 at room or close toroom temperature have been investigated. The product Cu(OAB...olid state reactions of o-aminobenzoic acid (HOAB) with Cu (OAc)_2·H_2O,Cu(HCOO)_2 · 4H_2O, anhydrous Cu (OAc)_2 and Cu (HCOO)_2 at room or close toroom temperature have been investigated. The product Cu(OAB)_2 with a high yieldwas synthesized very conveniently compared witb the solution phase method. Thekinetic behavior was studied by means of the isothermal electrical conductivity mea-surement. The reactivity was found to decrease in the order : Cu(OAc)_2· H_2O>Cu(OAc)_2>Cu (HCOO)_2 ·4H_2O>Cu (HCOO)_2, which was attributable to the crystalstructures of the copper salts.展开更多
The oxidation of lignite and bituminous coal samples modified by 5 wt%(in terms of dry salt)addition of copper salts Cu(NO_(3))_(2),CuSO_(4),and Cu(CH_(3)COO)_(2) was studied.The samples’reactivity was studied by the...The oxidation of lignite and bituminous coal samples modified by 5 wt%(in terms of dry salt)addition of copper salts Cu(NO_(3))_(2),CuSO_(4),and Cu(CH_(3)COO)_(2) was studied.The samples’reactivity was studied by thermogravimetry within a temperature range of 45–600℃ at a heating rate of 2.5℃/min in an oxidizing environment.The introduction of activating additives has resulted in a significant decrease in the temperature of intense oxidation onset(ΔT_(i)=20/94℃),in a reduction in the sample residence time in the volatile matter release region(Δt_(e)=2/22 min)and the total duration of the coal combustible mass oxidation(Δt_(f)=8/14 min).The Friedman method was used to calculate the activation energy values for the oxidation process of the modified samples.The maximum change in activation energy values was observed for the bituminous coal sample.The possible mechanism behind the action of the copper-salt additives,which activate the oxidation of lignite and bituminous coal,is discussed.According to the data of mass spectrometric analysis,the concentration of NOx in the reaction products decreases as the temperature of the activated oxidation process is shifted towards the low-temperature region.展开更多
N,N＇-Diarylhydrazines have been prepared via the reaction of N-Boc-aryl hydrazines with boronic acids mediated by copper acetate. This mild reaction condition tolerates the presence of a variety of functional groups.
The title complex, {[Cu2（4,4＇-bipyridine）2（μ-O2CMe）2（O2CMe）2],H2O}n 1, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a = 13.4474...The title complex, {[Cu2（4,4＇-bipyridine）2（μ-O2CMe）2（O2CMe）2],H2O}n 1, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a = 13.4474（5）, b = 11.7566（2）, c = 19.5380（6）A, β = 92.930（2）°, V = 3084.84（16） A^3, Z = 4, Cu2C28N409H30, Mr = 693.64, Dc = 1.494 g/cm^3, F（000） = 1424 and μ（MoKα） = 1.436 mm^-1. With the use of 2062 observed reflections （I 〉 2σ（I））, the structure was refined to R = 0.0769 and wR = 0.2154. In complex 1, the dimeric copper acetate units are linked through 4,4’-bipyridine to yield ID molecular ladders. These ladders are connected via O-H…O hydrogen bonds to generate 2D layers, which are further linked through C-H…O hydrogen bonds to give a 3D supramolecular network.展开更多
1 Introduction A variety of Pd(Ⅱ)-catalyzed oxidative transformations ot allcenes with oxygen nucleophiles are catalyzed by PdX_(2)(X=OAc,Cl,etc)with CuX_(n)(n=1 or 2)under O_(2).In the so-called Wacker catalyst of s...1 Introduction A variety of Pd(Ⅱ)-catalyzed oxidative transformations ot allcenes with oxygen nucleophiles are catalyzed by PdX_(2)(X=OAc,Cl,etc)with CuX_(n)(n=1 or 2)under O_(2).In the so-called Wacker catalyst of such,Pd(OAc)_(2) is less reactive compared to PdCl_(2).In an attempt to increase the reactivity of Pd(OAc)_(2),we have now found that tuning of Cu site with catechol gives an intriguing reactivity to Pd(OAc)_(2),which is unprecedented in the chemistry of palladium.展开更多
基金Research Grant from Liaoning Province Office of EducationChina(No.L2014395)+1 种基金the Natural Science Foundation of Liaoning Province(No.201602711)Supporting Program for Young Researchers from Sheyang Pharmaceutical University。
文摘In this study, arsenic trioxide(ATO) was encapsulated in liposomes via copper acetate(Cu(OAc)2) gradients and high entrapment efficiency of over 80% was obtained. The average particle size and the zeta-potential of the liposomes were detected to be 115.1 ± 29.1 nm and-21.97 ± 0.6 m V, respectively. The TEM images showed rod-like precipitates in the inner aqueous phase, which was supposed be due to the formation of insoluble ATO–Cu complex.The in vitro drug release of ATO–Cu liposomes exhibited a sustained release over 72 h, and the release rates decreased with the increase of the p H of release media. Pharmacokinetic and tissue distribution studies of ATO liposomes showed significantly reduced plasma clearance rate, increased AUC0–12h and T1/2, and improved tumor distribution of As compared to iv administration of ATO solution. The anti-tumor effect of ATO loaded liposomes to S180 tumor-bearing mice was significantly improved with a tumor inhibition rate of 61.2%,meanwhile the toxicity of encapsulated ATO was greatly decreased. In conclusion, ATO can be effectively encapsulated into liposomes by remote loading method via Cu(OAc)2 gradients;the co-administration of ATO and Cu(Ⅱ) via liposomal formulation may find wide applications in the treatment of various tumors.
基金Research was supported in part by funds provided by USDA-NIFA Sustainable Agriculture Systems,Grant No.2019-69012-29905Title of Project:Empowering US Broiler Production for Transformation and Sustainability USDA-NIFA(Sustainable Agriculture Systems):No.2019-69012-29905.
文摘Background:Interest in the use of natural feed additives as an alternative to antimicrobials in the poultry industry has increased in recent years because of the risk of bacterial resistance.One of the most studied groups are polyphenolic compounds,given their advantages over other types of additives and their easy potentiation of effects when complexes are formed with metal ions.Therefore,the objective of the present study was to evaluate the impact of dietary supplementation of copper acetate(CA),curcumin(CR),and their combination(CA-CR)against Salmonella Typhimurium colonization,intestinal permeability,and cecal microbiota composition in broiler chickens through a laboratory Salmonella infection model.S.Typhimurium recovery was determined on day 10 post-challenge by isolating Salmonella in homogenates of the right cecal tonsil(12 chickens per group)on Xylose Lysine Tergitol-4(XLT-4)with novobiocin and nalidixic acid.Intestinal integrity was indirectly determined by the fluorometric measurement of fluorescein isothiocyanate dextran(FITC-d)in serum samples from blood obtained on d 10 post-S.Typhimurium challenge.Finally,microbiota analysis was performed using the content of the left caecal tonsil of 5 chickens per group by sequencing V4 region of 16S rRNA gene.Results:The results showed that in two independent studies,all experimental treatments were able to significantly reduce the S.Typhimurium colonization in cecal tonsils(CT,P<0.0001)compared to the positive control(PC)group.However,only CA-CR was the most effective treatment in reducing S.Typhimurium counts in both independent studies.Furthermore,the serum fluorescein isothiocyanate dextran(FITC-d)concentration in chickens treated with CR was significantly lower when compared to PC(P=0.0084),which is related to a decrease in intestinal permeability and therefore intestinal integrity.The effect of dietary treatments in reducing Salmonella was further supported by the analysis of 16S rRNA gene sequences using Linear discriminant analysis effect size(LEfSe)since Salmonella was significantly enriched in PC group(LDA score>2.0 and P<0.05)compared to other groups.In addition,Coprobacillus,Eubacterium,and Clostridium were significantly higher in the PC group compared to other treatment groups.On the contrary,Fecalibacterium and Enterococcus in CR,unknown genus of Erysipelotrichaceae at CA-CR,and unknown genus of Lachnospiraceae at CA were significantly more abundant respectively.Conclusions:CR treatment was the most effective treatment to reduce S.Typhimurium intestinal colonization and maintain better intestinal homeostasis which might be achieved through modulation of cecal microbiota.
文摘This paper addressed the efect of copper acetate on the combustion characteristics of anthracite depending on the fractional composition of fuel and additive introduction method.Anthracite was impregnated with 5 wt%of Cu(CH_(3)COO)_(2)by mechanical mixing and incipient wetness impregnation.Four anthracite samples of diferent fraction with d<0.1 mm,d=0.1-0.5 mm,d=0.5-1.0 mm,and d=1.0-2.0 mm were compared.According to EDX mapping,incipient wetness impregnation provides a higher dispersion of the additive and its uniform distribution in the sample.The ignition and combustion characteristics of the modifed anthracite samples were studied by thermal analysis and high-speed video recording of the processes in a combustion chamber(at heating medium temperature of 800℃).It was found that copper acetate increases anthracite reactivity,which was evidenced by decreased onset temperature of combustion(ΔT_(i))by 35-190℃and reduced ignition delay time(Δτ_(i))by 2.1-5.4 s.Copper acetate reduces fuel underburning(on average by 70%)in the ash residue of anthracite and decreases the amount of CO and NO_(x)in gas-phase products(on average by 18.5%and 20.8%,respectively).The mechanism for activation of anthracite combustion by copper acetate is proposed.
文摘olid state reactions of o-aminobenzoic acid (HOAB) with Cu (OAc)_2·H_2O,Cu(HCOO)_2 · 4H_2O, anhydrous Cu (OAc)_2 and Cu (HCOO)_2 at room or close toroom temperature have been investigated. The product Cu(OAB)_2 with a high yieldwas synthesized very conveniently compared witb the solution phase method. Thekinetic behavior was studied by means of the isothermal electrical conductivity mea-surement. The reactivity was found to decrease in the order : Cu(OAc)_2· H_2O>Cu(OAc)_2>Cu (HCOO)_2 ·4H_2O>Cu (HCOO)_2, which was attributable to the crystalstructures of the copper salts.
基金This work was supported by the Ministry of Science and Higher Education of the Russian Federation(projects No.FSWW-2020-0022 and AAAA-A17-117041710086-6).
文摘The oxidation of lignite and bituminous coal samples modified by 5 wt%(in terms of dry salt)addition of copper salts Cu(NO_(3))_(2),CuSO_(4),and Cu(CH_(3)COO)_(2) was studied.The samples’reactivity was studied by thermogravimetry within a temperature range of 45–600℃ at a heating rate of 2.5℃/min in an oxidizing environment.The introduction of activating additives has resulted in a significant decrease in the temperature of intense oxidation onset(ΔT_(i)=20/94℃),in a reduction in the sample residence time in the volatile matter release region(Δt_(e)=2/22 min)and the total duration of the coal combustible mass oxidation(Δt_(f)=8/14 min).The Friedman method was used to calculate the activation energy values for the oxidation process of the modified samples.The maximum change in activation energy values was observed for the bituminous coal sample.The possible mechanism behind the action of the copper-salt additives,which activate the oxidation of lignite and bituminous coal,is discussed.According to the data of mass spectrometric analysis,the concentration of NOx in the reaction products decreases as the temperature of the activated oxidation process is shifted towards the low-temperature region.
文摘N,N＇-Diarylhydrazines have been prepared via the reaction of N-Boc-aryl hydrazines with boronic acids mediated by copper acetate. This mild reaction condition tolerates the presence of a variety of functional groups.
基金This work was supported by the Science Foundation of Fujian Provincial Key Laboratory of Polymer Materials
文摘The title complex, {[Cu2（4,4＇-bipyridine）2（μ-O2CMe）2（O2CMe）2],H2O}n 1, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a = 13.4474（5）, b = 11.7566（2）, c = 19.5380（6）A, β = 92.930（2）°, V = 3084.84（16） A^3, Z = 4, Cu2C28N409H30, Mr = 693.64, Dc = 1.494 g/cm^3, F（000） = 1424 and μ（MoKα） = 1.436 mm^-1. With the use of 2062 observed reflections （I 〉 2σ（I））, the structure was refined to R = 0.0769 and wR = 0.2154. In complex 1, the dimeric copper acetate units are linked through 4,4’-bipyridine to yield ID molecular ladders. These ladders are connected via O-H…O hydrogen bonds to generate 2D layers, which are further linked through C-H…O hydrogen bonds to give a 3D supramolecular network.
文摘1 Introduction A variety of Pd(Ⅱ)-catalyzed oxidative transformations ot allcenes with oxygen nucleophiles are catalyzed by PdX_(2)(X=OAc,Cl,etc)with CuX_(n)(n=1 or 2)under O_(2).In the so-called Wacker catalyst of such,Pd(OAc)_(2) is less reactive compared to PdCl_(2).In an attempt to increase the reactivity of Pd(OAc)_(2),we have now found that tuning of Cu site with catechol gives an intriguing reactivity to Pd(OAc)_(2),which is unprecedented in the chemistry of palladium.
