The dioxygen affinities and catalytic epoxidation performance of transition-metal hydroxamates were investigated for the first time. The effects of substituents on these properties were also discussed in the paper.
The oxygenation constants (Ko2) of cobalt(Ⅱ) hydroxamates (CoL^1 2-CoL^3 2) with benzo-15-crown-5 (B15C5) pendants were measured over the range of -5 to +20 ℃, and the values of thermodynamic parameters (...The oxygenation constants (Ko2) of cobalt(Ⅱ) hydroxamates (CoL^1 2-CoL^3 2) with benzo-15-crown-5 (B15C5) pendants were measured over the range of -5 to +20 ℃, and the values of thermodynamic parameters (ΔH^0 and ΔS^0) were calculated based on these (Ko2) values, Meanwhile, these crowned complexes were employed to the oxidation for p-xylene to p-toluic acid with air at 110Δ under normal atmospheric pressure. The effects of B15C5 pendant and the length of chain bonded to B15C5 in these complexes on the O2-binding capabilities and oxidation for p-xylene were investigated with the comparison of crown-free analogues CoL^4 2.展开更多
Fourteen new di n butyltin(IV) complexes of hydroxamic acids of the formula Bu 2 SnL 2 (HL=hydroxamic acids) were synthesized by the reaction of Bu 2 SnO and hydroxamic acids in dry toluene and ...Fourteen new di n butyltin(IV) complexes of hydroxamic acids of the formula Bu 2 SnL 2 (HL=hydroxamic acids) were synthesized by the reaction of Bu 2 SnO and hydroxamic acids in dry toluene and ethanol media. The compounds were characterized by elemental analyses, molecular weight, IR and 1 H NMR spectroscopy. The results indicate that n Bu 2 SnL 2 have distorted trans octahedral structure. The antitumor activity in vitro against human A 549 tumor cells and P388 leukemia was presented, and their structure activity relationship was discussed.展开更多
In this paper,using methyl cinnamate as raw material,the new cinnamic hydroxamic acid collector(CIHA)was synthesized by the hydroxylamine method.The collector performance of hydroxamic acid was investigated for scheel...In this paper,using methyl cinnamate as raw material,the new cinnamic hydroxamic acid collector(CIHA)was synthesized by the hydroxylamine method.The collector performance of hydroxamic acid was investigated for scheelite and gangue calcite,and the flotation separation test of scheelite and calcite was carried out with CIHA as the collector.The interaction mechanism between hydroxamic acid and scheelite minerals has also been investigated through zeta potential,Fourier transform infrared spectroscopy(FTIR)experiments,X-ray photoelectron spectroscopy(XPS)experiments,and density functional theory(DFT)calculation.The single mineral flotation test and artificially mixed ore showed that CIHA had an excellent collection effect and selectivity.Zeta potential,FTIR,and XPS showed that CIHA was adsorbed on the scheelite surface by strong chemical adsorption.The active group of CIHA was analyzed through quantum chemical calculation.It was speculated that C=O and N-O bonds could synthesize a five-membered chelated hydroxamic acid group with Ca element chelate on scheelite surface,changing hydrophobicity and making it more likely to emerge from the pulp.展开更多
BACKGROUND Hepatocellular carcinoma(HCC)is a common clinical condition with a poor prognosis and few effective treatment options.Potent anticancer agents for treating HCC must be identified.Epigenetics plays an essent...BACKGROUND Hepatocellular carcinoma(HCC)is a common clinical condition with a poor prognosis and few effective treatment options.Potent anticancer agents for treating HCC must be identified.Epigenetics plays an essential role in HCC tumorigenesis.Suberoylanilide hydroxamic acid(SAHA),the most common histone deacetylase inhibitor agent,triggers many forms of cell death in HCC.However,the underlying mechanism of action remains unclear.Family with sequence similarity 134 member B(FAM134B)-induced reticulophagy,a selective autophagic pathway,participates in the decision of cell fate and exhibits anticancer activity.This study focused on the relationship between FAM134B-induced reticulophagy and SAHA-mediated cell death.AIM To elucidate potential roles and underlying molecular mechanisms of reticulophagy in SAHA-induced HCC cell death.METHODS The viability,apoptosis,cell cycle,migration,and invasion of SAHA-treated Huh7 and MHCC97L cells were measured.Proteins related to the reticulophagy pathway,mitochondria-endoplasmic reticulum(ER)contact sites,intrinsic mitochondrial apoptosis,and histone acetylation were quantified using western blotting.ER and lysosome colocalization,and mitochondrial Ca^(2+)levels were characterized via confocal microscopy.The level of cell death was evaluated through Hoechst 33342 staining and propidium iodide colocalization.Chromatin immunoprecipitation was used to verify histone H4 lysine-16 acetylation in the FAM134B promoter region.RESULTS After SAHA treatment,the proliferation of Huh7 and MHCC97L cells was significantly inhibited,and the migration and invasion abilities were greatly blocked in vitro.This promoted apoptosis and caused G1 phase cells to increase in a concentration-dependent manner.Following treatment with SAHA,ER-phagy was activated,thereby triggering autophagy-mediated cell death of HCC cells in vitro.Western blotting and chromatin immunoprecipitation assays confirmed that SAHA regulated FAM134B expression by enhancing the histone H4 lysine-16 acetylation in the FAM134B promoter region.Further,SAHA disturbed the Ca^(2+)homeostasis and upregulated the level of autocrine motility factor receptor and proteins related to mitochondria-endoplasmic reticulum contact sites in HCC cells.Additionally,SAHA decreased the mitochondrial membrane potential levels,thereby accelerating the activation of the reticulophagy-mediated mitochondrial apoptosis pathway and promoting HCC cell death in vitro.CONCLUSION SAHA stimulates FAM134B-mediated ER-phagy to synergistically enhance the mitochondrial apoptotic pathway,thereby enhancing HCC cell death.展开更多
The oxygenation of cobalt (II) hydroxamates (CoL2) and its catalytic performance in oxidation of p-xylene to p-toluic acid (PTA) were examined. The effects of X and Y bonded to hydroxamate group on dioxygen affinitie...The oxygenation of cobalt (II) hydroxamates (CoL2) and its catalytic performance in oxidation of p-xylene to p-toluic acid (PTA) were examined. The effects of X and Y bonded to hydroxamate group on dioxygen affinities and catalytic oxidation performance were also investigated.展开更多
Siderophores,being iron-chelators,have received much attention in environmental research,medicine,and biotechnology because of their high affinity and specificity to a wide range of metals.This study aimed to investig...Siderophores,being iron-chelators,have received much attention in environmental research,medicine,and biotechnology because of their high affinity and specificity to a wide range of metals.This study aimed to investigate siderophore production of culturable soil fungi from Mt.Yangbew,Tawang,La Trinidad,Benguet and to determine their chemical characteristics.Siderophore production was detected and quantified using Chrome Azurol Sulphonate assay while the siderophore characterization was through FeCl_(3),Csáky’s and Arnow’s tests.It was found that 11 out of 20 pure cultures,which showed positive CAS assay results,produce hydroxamates.ITS primers were used in PCR amplification for the molecular identification of the top-four siderophore-producers.Based on BLASTn analyses of their sequences,the isolates were found to be most homologous to species of Talaromyces,Byssochlamys,Paecilomyces,and Penicillium.The identified species were subjected to phylogenetic analysis using MEGA 7 to the show evolutionary history and relationship among the fungal species.展开更多
2,4-Dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA), the dominant benzoxazinoid hydroxamic acid in maize (Zea Mays L.), serves as important factors of resistance against insects and microbial diseases, ...2,4-Dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA), the dominant benzoxazinoid hydroxamic acid in maize (Zea Mays L.), serves as important factors of resistance against insects and microbial diseases, allelochemicals used in competition with other plants. In this paper, a novel and simple method for the isolation and purification of DIMBOA from maize seedlings was developed. Frozen shoots from 7-d-old maize seedlings (1 000×g) were firstly defrosted and then were directly homogenized and extracted with ethyl acetate. The macerate was allowed to stand at room temperature (25±2)°C for 1 h to allow enzymatic release of DIMBOA from DIMBOA-glucoside. Then the ethyl acetate phase was filtered, dried and evaporated to dryness. The resulting light-tan, semicrystalline residue was stored at -20°C for 24 h. Upon recrystallization from acetone-hexane, a relative higher yield (0.58 g) of pure DIMBOA crystals was obtained compared with the yield afforded by Woodward methodology (0.26 g).展开更多
Flotation separation of smithsonite from calcite is difficult due to their similar surface properties.In the present study,a reagent scheme of depressant calcium lignosulphonate(CLS) and collector benzyl hydroxamic ac...Flotation separation of smithsonite from calcite is difficult due to their similar surface properties.In the present study,a reagent scheme of depressant calcium lignosulphonate(CLS) and collector benzyl hydroxamic acid(BHA) was introduced in the flotation of smithsonite from calcite.Microflotation tests revealed that the efficient flotation of smithsonite from calcite could only be obtained with the addition order of BHA before CLS,which was opposite to the widely-used order that adding depressant prior to the collector.The zeta potential measurements indicated that BHA selectively adsorbed onto smithsonite surface,then not allowed the CLS adsorption onto the smithsonite surface rather than calcite surface because of the steric hindrance,thereby the smithsonite surface remained hydrophobic while calcite surface became more hydrophilic after the addition of CLS.As a result,the calcite flotation was completely depressed while the smithsonite flotation recovery was still in high value,leading to the optimal flotation separation performance.展开更多
Background: Histone deacetylases(HDACs) inhibitors are new anti-fibrotic drugs that inhibit the activity of hepatic stellate cells. The present study focused on the anti-fibrotic function of HDAC inhibitor suberoylani...Background: Histone deacetylases(HDACs) inhibitors are new anti-fibrotic drugs that inhibit the activity of hepatic stellate cells. The present study focused on the anti-fibrotic function of HDAC inhibitor suberoylanilide hydroxamic acid(SAHA) by suppressing transforming growth factor-β1(TGF-β1) signaling. Methods: Male Sprague-Dawley rats were used to induce liver fibrosis with carbon tetrachloride(CCl 4) and LX2 cell(human hepatic stellate cell line) was stimulated by TGF-β1. Both animals and cells were treated with SAHA. The Smad7 and connective tissue growth factor(CTGF) mRNA levels were detected by real-time polymerase chain reaction(PCR). Western blotting was used to examine the protein levels of CTGF, Histone H3(H3), Smad7, Smad2/3, Acetyl-Histone H3(AH3), HDAC2, α-smooth muscle actin( α-SMA), HDAC6, p-Smad2/3 and HDAC8. In addition, the TGF-β1 and liver enzyme levels from rat serum were detected. Histopathological changes were examined by hematoxylin and eosin(HE), Sirius red and Masson trichrome staining. The α-SMA expression was detected by immumohistochemical staining. Results: Compared with control group, the TGF-β1 and liver enzyme levels from rat serum, together with the mRNA levels of CTGF and protein levels of CTGF, HDAC2, α-SMA, HDAC6, p-Smad2/3 and HDAC8 were elevated in fibrotic rats( P < 0.01). But the Smad7 mRNA and AH3 protein levels were notably suppressed in the fibrotic rats( P < 0.01). Pathological examination showed the typical changes of liver fibrosis in the fibrotic rats. After the treatment with SAHA, the levels of liver enzymes, TGF-β1, CTGF, HDAC2, α-SMA, HDAC6, p-Smad2/3 and HDAC8 were reduced( P < 0.01) and Smad7 and AH3 protein contents were elevated in liver fibrotic rats( P < 0.01). Moreover, immumohistochemistry showed that SAHA significantly suppressed the α-SMA protein content in fibrotic liver( P < 0.01). Conclusion: The HDAC inhibitor SAHA alleviated liver fibrosis by suppressing the TGF-β1 signaling.展开更多
AIM: To investigate the effects of suberoylanilide hydroxamic acid(SAHA) on proliferation and apoptosis of a human hepatocellular carcinoma cell line(HepG2.2.15) and hepatitis B virus(HBV) replication.METHODS: HepG2.2...AIM: To investigate the effects of suberoylanilide hydroxamic acid(SAHA) on proliferation and apoptosis of a human hepatocellular carcinoma cell line(HepG2.2.15) and hepatitis B virus(HBV) replication.METHODS: HepG2.2.15 cells were treated with different concentrations of SAHA.Cell morphology was examined by confocal laser scanning microscopy,and cell proliferation was determined using a MTT colorimetric assay.Flow cytometry was used to detect apoptosis and determine cell cycle phase,while hepatitis B surface antigen and hepatitis B e antigen content were measured using chemiluminescence.Reverse transcription polymerase chain reaction was performed to measure HBV DNA in cell lysate.RESULTS: Cell proliferation rates were significantly reduced by the addition of SAHA.The inhibitory effect of SAHA on cell proliferation was both time-and dosedependent.After 24 h of treatment with SAHA,the early cell apoptotic rate increased from 3.25% to 21.02%(P = 0.041).The proportion of G0 /G1 phase cells increased from 50.3% to 65.3%(P = 0.039),while that of S phase cells decreased from 34.9% to 20.6%(P = 0.049).After 48 h of treatment,hepatitis B surface antigen and hepatitis B e antigen content increased from 12.33 ± 0.62 to 25.42 ± 2.67(P = 0.020) and 28.92 ± 1.24 to 50.48 ± 1.85(P = 0.026),respectively.Furthermore,HBV DNA content increased from 4.54 ± 0.46 to 8.34 ± 0.59(P = 0.029).CONCLUSION: SAHA inhibits HepG2.2.15 cell proliferation,promotes apoptosis,and stimulates HBV replication.In combination with anti-HBV drugs,SAHA may potentially be used cautiously for treatment of hepatocellular carcinoma.展开更多
The extraction separation of germanium from indium raffinate in hydrometallurgical zinc process was discussed. The conditions and mechanism of the extraction with hydroxamic acid HGS98 have been investigated in detail...The extraction separation of germanium from indium raffinate in hydrometallurgical zinc process was discussed. The conditions and mechanism of the extraction with hydroxamic acid HGS98 have been investigated in detail. The results show that u sing 2% (mass fraction) hydroxamic acid HGS98 and 5% D 2EHPA as synergist, germanium is extracted (1 stage) over 99% in 5 min at phase ratio ( V o∶ V a) of 1∶5 from indium raffinate with original acidity. Then, using 2 mol·L -1 NH 4F as strip liquor, the stripping recovery is over 98% in 15 min at phase ratio of 1∶1. This process has the following advantages:easy to operate, high recovery and selectivity, and lower investment cost. It provides a new way to recover rare metal-germanium from metallurgical spent residues.展开更多
The complexes RE_2(DHYA)_3 centre dot nH_2O in the title bar were synthesizedthrough some reactions of trivalent rare-earth ions. In the process of synthesis, dihydroxamicacids were taken as ligands while the alcohol ...The complexes RE_2(DHYA)_3 centre dot nH_2O in the title bar were synthesizedthrough some reactions of trivalent rare-earth ions. In the process of synthesis, dihydroxamicacids were taken as ligands while the alcohol was taken as a solvent. The ligands includedadipylhydroxamic acid (ADHA), p-phthalichydroxamic acid (PPHA), oxalohydroxamic acid (OXHA),butadihydroxamic acid (BDHA), o-phthalichydroxamic acid (OPHA), benzoylhydroxamic acid (BHA), etc.Measured at 25 deg C, the molar conductances in various modes are 13.00-21.05 S centre dot cm^2centre dot mol^(-1), which shows that rare-earth complexes are nonelectrolytes and the hydroxaminogroups of the complexes have taken part in bonding. Infrared spectra, ultraviolet spectra, nuclearmagnetic resonance (~1HNMR) spectra, and fluorescence spectra were used to investigate thecomplexes. Experiments have proved that the complexes of En^(3+)and Tb^(3+) with aromatic hydroxamicacids have good fluorescent characteristics.展开更多
Synergistic extraction has been proven to enhance extractability and selectivity for the separation of cadmium and zinc from magnesium and calcium in the sulfuric acid medium with Mextral V10 and Mextral 622H(aromatic...Synergistic extraction has been proven to enhance extractability and selectivity for the separation of cadmium and zinc from magnesium and calcium in the sulfuric acid medium with Mextral V10 and Mextral 622H(aromatic hydroxamic)mixtures diluted in DT100.Mixtures of Mextral V10 and 622H are highly selective for Zn and Cd over Mg and Ca compared with the single Mextral V10,resulting in larger synergistic shifts for zinc and cadmium with theΔpH_(50(Zn–Ca))values increasing substantially from0.83 to 1.73 pH units andΔpH_(50(Cd–Ca))values increasing from 0.63 to 2.13 p H units.The aqueous to organic ratio(A/O ratio),the saponification ratio of Mextral V10 and extracting agent concentration were studied on the effect of metal ions extraction,which helped to increase the organic capacity of metal extraction.The Mc Cabe-Thiele plot for Cd and Zn extraction with 5%(volume fraction)Mextral V10 and 5%Mextral 622H extractants mixture indicate the necessity of only one theoretical stages at an A/O ratio of 1.5:1.One stage extraction simulation test conducted at pH 6.50 shows that Cd and Zn reach the extraction of 99.6%and 97.9%,respectively,and only low levels of magnesium and calcium are extracted in the organic phase.The extracted Zn^(2+)or Cd^(2+)-organic species are Zn(A_1)(A_2)or Cd(A_1)(A_2)with the mixture system by slope analysis.展开更多
A new kind of polyacrylamide derivate, hydroximic polyacrylamide (HPAM), was prepared from polyacrylamide (PAM) with hydroxylamine hydrochloride in KOH/alcohol solution. Based on colorimetric method in the measurement...A new kind of polyacrylamide derivate, hydroximic polyacrylamide (HPAM), was prepared from polyacrylamide (PAM) with hydroxylamine hydrochloride in KOH/alcohol solution. Based on colorimetric method in the measurement of C 7 9 alkyl hydroximic acid, the substitution degree of HPAM was determined by selecting octyl hydroximic acid as a primary standard substance. The effects of temperature, the amount of hydroxylamine and potassium hydroxide, and the reaction time on the reaction are discussed. HPAM with 5.78% substitution of degree was acquired by optimizing the reaction conditions. IR spectra revealed that tautomerism appears in the HPAM, and that HPAM exists in both the forms of hydroxamic type and hydroximic type, and the latter type can easily lead to the forming of intramolecular hydrogen bond.展开更多
Periodontitis is a type of chronic inflammation in the gingival tissue caused by infectious bacteria colonizing the surface of the teeth,leading to the destruction of tooth-supporting tissues and loss of alveolar bone...Periodontitis is a type of chronic inflammation in the gingival tissue caused by infectious bacteria colonizing the surface of the teeth,leading to the destruction of tooth-supporting tissues and loss of alveolar bone.Suberoylanilide hydroxamic acid(SAHA),a class of histone deacetylase(HDAC)inhibitor,has the potential to stimulate osteoblast differentiation by acetylating histone proteins,and thus suppressing the expression of adipogenic and chondrogenic genes.However,the effect of SAHA on the differentiation of human periodontal ligament stem cells(hPDLSCs)is yet to be elucidated.Herein,we investigated the effects of SAHA on in vitro proliferation and differentiation of hPDLSCs by MTT assay,Alizarin Red-S,and alkaline phosphatase staining,and real-time PCR.Notably,300 ng/mL SAHA treatment enhanced the proliferation and mineralization of hPDLSCs,indicating their osteogenic potential.Moreover,a significant enhancement of osteogenesis gene markers and proteins was observed.We also demonstrated that ERK is a positive regulator of Runx2 transcription factors during osteoblast differentiation.These results indicate that SAHA may be a useful osteogenic induction agent for periodontal bone regeneration.展开更多
文摘The dioxygen affinities and catalytic epoxidation performance of transition-metal hydroxamates were investigated for the first time. The effects of substituents on these properties were also discussed in the paper.
基金The authors gratefully acknowledge the grants from the National Natural Science Foundation of China(No.20072025)Education 0ffice Foundation of Sichuan Province(No.2005C012)Sichuan Provincial Department of Science&Technology(No.2006J13-143)in support of this work.
文摘The oxygenation constants (Ko2) of cobalt(Ⅱ) hydroxamates (CoL^1 2-CoL^3 2) with benzo-15-crown-5 (B15C5) pendants were measured over the range of -5 to +20 ℃, and the values of thermodynamic parameters (ΔH^0 and ΔS^0) were calculated based on these (Ko2) values, Meanwhile, these crowned complexes were employed to the oxidation for p-xylene to p-toluic acid with air at 110Δ under normal atmospheric pressure. The effects of B15C5 pendant and the length of chain bonded to B15C5 in these complexes on the O2-binding capabilities and oxidation for p-xylene were investigated with the comparison of crown-free analogues CoL^4 2.
基金ProjectsupportedbytheNationalNaturalScienceFoundationofChina (No .2 97710 2 3)andtheNaturalScienceFoundationofShanxiProvince
文摘Fourteen new di n butyltin(IV) complexes of hydroxamic acids of the formula Bu 2 SnL 2 (HL=hydroxamic acids) were synthesized by the reaction of Bu 2 SnO and hydroxamic acids in dry toluene and ethanol media. The compounds were characterized by elemental analyses, molecular weight, IR and 1 H NMR spectroscopy. The results indicate that n Bu 2 SnL 2 have distorted trans octahedral structure. The antitumor activity in vitro against human A 549 tumor cells and P388 leukemia was presented, and their structure activity relationship was discussed.
基金the National Nature Science Foundation of China(No.51774152)Jiangxi Provincial Education Department(GJJ200816)+1 种基金“Double height project”in Jiangxi province(No.[2022]223)the National Nature Science Foundation of China(No.52264023).
文摘In this paper,using methyl cinnamate as raw material,the new cinnamic hydroxamic acid collector(CIHA)was synthesized by the hydroxylamine method.The collector performance of hydroxamic acid was investigated for scheelite and gangue calcite,and the flotation separation test of scheelite and calcite was carried out with CIHA as the collector.The interaction mechanism between hydroxamic acid and scheelite minerals has also been investigated through zeta potential,Fourier transform infrared spectroscopy(FTIR)experiments,X-ray photoelectron spectroscopy(XPS)experiments,and density functional theory(DFT)calculation.The single mineral flotation test and artificially mixed ore showed that CIHA had an excellent collection effect and selectivity.Zeta potential,FTIR,and XPS showed that CIHA was adsorbed on the scheelite surface by strong chemical adsorption.The active group of CIHA was analyzed through quantum chemical calculation.It was speculated that C=O and N-O bonds could synthesize a five-membered chelated hydroxamic acid group with Ca element chelate on scheelite surface,changing hydrophobicity and making it more likely to emerge from the pulp.
基金the National Natural Science Foundation of China,No.82260127Guizhou Provincial Science and Technology Projects,No.Qiankehe Jichu-ZK[2021]365 and Qiankehe Jichu-ZK[2021]364+2 种基金National Natural Science Foundation Cultivation Project of Guizhou Medical University,No.20NSP016Guizhou Provincial Natural Science Foundation,No.[2021]4029 and[2022]4017Science and Technology Foundation of Guizhou Provincial Health Commission,No.gzwjkj2019-1-102.
文摘BACKGROUND Hepatocellular carcinoma(HCC)is a common clinical condition with a poor prognosis and few effective treatment options.Potent anticancer agents for treating HCC must be identified.Epigenetics plays an essential role in HCC tumorigenesis.Suberoylanilide hydroxamic acid(SAHA),the most common histone deacetylase inhibitor agent,triggers many forms of cell death in HCC.However,the underlying mechanism of action remains unclear.Family with sequence similarity 134 member B(FAM134B)-induced reticulophagy,a selective autophagic pathway,participates in the decision of cell fate and exhibits anticancer activity.This study focused on the relationship between FAM134B-induced reticulophagy and SAHA-mediated cell death.AIM To elucidate potential roles and underlying molecular mechanisms of reticulophagy in SAHA-induced HCC cell death.METHODS The viability,apoptosis,cell cycle,migration,and invasion of SAHA-treated Huh7 and MHCC97L cells were measured.Proteins related to the reticulophagy pathway,mitochondria-endoplasmic reticulum(ER)contact sites,intrinsic mitochondrial apoptosis,and histone acetylation were quantified using western blotting.ER and lysosome colocalization,and mitochondrial Ca^(2+)levels were characterized via confocal microscopy.The level of cell death was evaluated through Hoechst 33342 staining and propidium iodide colocalization.Chromatin immunoprecipitation was used to verify histone H4 lysine-16 acetylation in the FAM134B promoter region.RESULTS After SAHA treatment,the proliferation of Huh7 and MHCC97L cells was significantly inhibited,and the migration and invasion abilities were greatly blocked in vitro.This promoted apoptosis and caused G1 phase cells to increase in a concentration-dependent manner.Following treatment with SAHA,ER-phagy was activated,thereby triggering autophagy-mediated cell death of HCC cells in vitro.Western blotting and chromatin immunoprecipitation assays confirmed that SAHA regulated FAM134B expression by enhancing the histone H4 lysine-16 acetylation in the FAM134B promoter region.Further,SAHA disturbed the Ca^(2+)homeostasis and upregulated the level of autocrine motility factor receptor and proteins related to mitochondria-endoplasmic reticulum contact sites in HCC cells.Additionally,SAHA decreased the mitochondrial membrane potential levels,thereby accelerating the activation of the reticulophagy-mediated mitochondrial apoptosis pathway and promoting HCC cell death in vitro.CONCLUSION SAHA stimulates FAM134B-mediated ER-phagy to synergistically enhance the mitochondrial apoptotic pathway,thereby enhancing HCC cell death.
基金This work is supported by the National Natural Science Foundation of China(Grant No.2007205).
文摘The oxygenation of cobalt (II) hydroxamates (CoL2) and its catalytic performance in oxidation of p-xylene to p-toluic acid (PTA) were examined. The effects of X and Y bonded to hydroxamate group on dioxygen affinities and catalytic oxidation performance were also investigated.
基金the support of the Department of Biology,College of Science,University of the Philippines Baguio for the conduct of this study.
文摘Siderophores,being iron-chelators,have received much attention in environmental research,medicine,and biotechnology because of their high affinity and specificity to a wide range of metals.This study aimed to investigate siderophore production of culturable soil fungi from Mt.Yangbew,Tawang,La Trinidad,Benguet and to determine their chemical characteristics.Siderophore production was detected and quantified using Chrome Azurol Sulphonate assay while the siderophore characterization was through FeCl_(3),Csáky’s and Arnow’s tests.It was found that 11 out of 20 pure cultures,which showed positive CAS assay results,produce hydroxamates.ITS primers were used in PCR amplification for the molecular identification of the top-four siderophore-producers.Based on BLASTn analyses of their sequences,the isolates were found to be most homologous to species of Talaromyces,Byssochlamys,Paecilomyces,and Penicillium.The identified species were subjected to phylogenetic analysis using MEGA 7 to the show evolutionary history and relationship among the fungal species.
基金supported by the National Natural Science Foundation of China (30900951)
文摘2,4-Dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA), the dominant benzoxazinoid hydroxamic acid in maize (Zea Mays L.), serves as important factors of resistance against insects and microbial diseases, allelochemicals used in competition with other plants. In this paper, a novel and simple method for the isolation and purification of DIMBOA from maize seedlings was developed. Frozen shoots from 7-d-old maize seedlings (1 000×g) were firstly defrosted and then were directly homogenized and extracted with ethyl acetate. The macerate was allowed to stand at room temperature (25±2)°C for 1 h to allow enzymatic release of DIMBOA from DIMBOA-glucoside. Then the ethyl acetate phase was filtered, dried and evaporated to dryness. The resulting light-tan, semicrystalline residue was stored at -20°C for 24 h. Upon recrystallization from acetone-hexane, a relative higher yield (0.58 g) of pure DIMBOA crystals was obtained compared with the yield afforded by Woodward methodology (0.26 g).
基金the support of Natural Science Foundation of China (51804238, 51904214)the Open Foundation of State Key Laboratory of Mineral Processing, BGRIMM Technology (No. BGRIMM-KJSKL-2021-22)the Fundamental Research Funds for the Central Universities (2021IVA110, 2021IVA039)。
文摘Flotation separation of smithsonite from calcite is difficult due to their similar surface properties.In the present study,a reagent scheme of depressant calcium lignosulphonate(CLS) and collector benzyl hydroxamic acid(BHA) was introduced in the flotation of smithsonite from calcite.Microflotation tests revealed that the efficient flotation of smithsonite from calcite could only be obtained with the addition order of BHA before CLS,which was opposite to the widely-used order that adding depressant prior to the collector.The zeta potential measurements indicated that BHA selectively adsorbed onto smithsonite surface,then not allowed the CLS adsorption onto the smithsonite surface rather than calcite surface because of the steric hindrance,thereby the smithsonite surface remained hydrophobic while calcite surface became more hydrophilic after the addition of CLS.As a result,the calcite flotation was completely depressed while the smithsonite flotation recovery was still in high value,leading to the optimal flotation separation performance.
基金supported by a grant from the National Natural Science Foundation of China(81870413)
文摘Background: Histone deacetylases(HDACs) inhibitors are new anti-fibrotic drugs that inhibit the activity of hepatic stellate cells. The present study focused on the anti-fibrotic function of HDAC inhibitor suberoylanilide hydroxamic acid(SAHA) by suppressing transforming growth factor-β1(TGF-β1) signaling. Methods: Male Sprague-Dawley rats were used to induce liver fibrosis with carbon tetrachloride(CCl 4) and LX2 cell(human hepatic stellate cell line) was stimulated by TGF-β1. Both animals and cells were treated with SAHA. The Smad7 and connective tissue growth factor(CTGF) mRNA levels were detected by real-time polymerase chain reaction(PCR). Western blotting was used to examine the protein levels of CTGF, Histone H3(H3), Smad7, Smad2/3, Acetyl-Histone H3(AH3), HDAC2, α-smooth muscle actin( α-SMA), HDAC6, p-Smad2/3 and HDAC8. In addition, the TGF-β1 and liver enzyme levels from rat serum were detected. Histopathological changes were examined by hematoxylin and eosin(HE), Sirius red and Masson trichrome staining. The α-SMA expression was detected by immumohistochemical staining. Results: Compared with control group, the TGF-β1 and liver enzyme levels from rat serum, together with the mRNA levels of CTGF and protein levels of CTGF, HDAC2, α-SMA, HDAC6, p-Smad2/3 and HDAC8 were elevated in fibrotic rats( P < 0.01). But the Smad7 mRNA and AH3 protein levels were notably suppressed in the fibrotic rats( P < 0.01). Pathological examination showed the typical changes of liver fibrosis in the fibrotic rats. After the treatment with SAHA, the levels of liver enzymes, TGF-β1, CTGF, HDAC2, α-SMA, HDAC6, p-Smad2/3 and HDAC8 were reduced( P < 0.01) and Smad7 and AH3 protein contents were elevated in liver fibrotic rats( P < 0.01). Moreover, immumohistochemistry showed that SAHA significantly suppressed the α-SMA protein content in fibrotic liver( P < 0.01). Conclusion: The HDAC inhibitor SAHA alleviated liver fibrosis by suppressing the TGF-β1 signaling.
文摘AIM: To investigate the effects of suberoylanilide hydroxamic acid(SAHA) on proliferation and apoptosis of a human hepatocellular carcinoma cell line(HepG2.2.15) and hepatitis B virus(HBV) replication.METHODS: HepG2.2.15 cells were treated with different concentrations of SAHA.Cell morphology was examined by confocal laser scanning microscopy,and cell proliferation was determined using a MTT colorimetric assay.Flow cytometry was used to detect apoptosis and determine cell cycle phase,while hepatitis B surface antigen and hepatitis B e antigen content were measured using chemiluminescence.Reverse transcription polymerase chain reaction was performed to measure HBV DNA in cell lysate.RESULTS: Cell proliferation rates were significantly reduced by the addition of SAHA.The inhibitory effect of SAHA on cell proliferation was both time-and dosedependent.After 24 h of treatment with SAHA,the early cell apoptotic rate increased from 3.25% to 21.02%(P = 0.041).The proportion of G0 /G1 phase cells increased from 50.3% to 65.3%(P = 0.039),while that of S phase cells decreased from 34.9% to 20.6%(P = 0.049).After 48 h of treatment,hepatitis B surface antigen and hepatitis B e antigen content increased from 12.33 ± 0.62 to 25.42 ± 2.67(P = 0.020) and 28.92 ± 1.24 to 50.48 ± 1.85(P = 0.026),respectively.Furthermore,HBV DNA content increased from 4.54 ± 0.46 to 8.34 ± 0.59(P = 0.029).CONCLUSION: SAHA inhibits HepG2.2.15 cell proliferation,promotes apoptosis,and stimulates HBV replication.In combination with anti-HBV drugs,SAHA may potentially be used cautiously for treatment of hepatocellular carcinoma.
文摘The extraction separation of germanium from indium raffinate in hydrometallurgical zinc process was discussed. The conditions and mechanism of the extraction with hydroxamic acid HGS98 have been investigated in detail. The results show that u sing 2% (mass fraction) hydroxamic acid HGS98 and 5% D 2EHPA as synergist, germanium is extracted (1 stage) over 99% in 5 min at phase ratio ( V o∶ V a) of 1∶5 from indium raffinate with original acidity. Then, using 2 mol·L -1 NH 4F as strip liquor, the stripping recovery is over 98% in 15 min at phase ratio of 1∶1. This process has the following advantages:easy to operate, high recovery and selectivity, and lower investment cost. It provides a new way to recover rare metal-germanium from metallurgical spent residues.
基金This Work was Financially Supported by the National Natural Science Foundation ofjiangxi Province (-1181).
文摘The complexes RE_2(DHYA)_3 centre dot nH_2O in the title bar were synthesizedthrough some reactions of trivalent rare-earth ions. In the process of synthesis, dihydroxamicacids were taken as ligands while the alcohol was taken as a solvent. The ligands includedadipylhydroxamic acid (ADHA), p-phthalichydroxamic acid (PPHA), oxalohydroxamic acid (OXHA),butadihydroxamic acid (BDHA), o-phthalichydroxamic acid (OPHA), benzoylhydroxamic acid (BHA), etc.Measured at 25 deg C, the molar conductances in various modes are 13.00-21.05 S centre dot cm^2centre dot mol^(-1), which shows that rare-earth complexes are nonelectrolytes and the hydroxaminogroups of the complexes have taken part in bonding. Infrared spectra, ultraviolet spectra, nuclearmagnetic resonance (~1HNMR) spectra, and fluorescence spectra were used to investigate thecomplexes. Experiments have proved that the complexes of En^(3+)and Tb^(3+) with aromatic hydroxamicacids have good fluorescent characteristics.
基金Projects(20151BBG70009,20151BBE50115)supported by Jiangxi Science and Technology Projects,ChinaProjects(2014-YYB-06,2014-YYB-11)supported by Scientific Research and Development Project of Jiangxi Academy of Sciences,China
文摘Synergistic extraction has been proven to enhance extractability and selectivity for the separation of cadmium and zinc from magnesium and calcium in the sulfuric acid medium with Mextral V10 and Mextral 622H(aromatic hydroxamic)mixtures diluted in DT100.Mixtures of Mextral V10 and 622H are highly selective for Zn and Cd over Mg and Ca compared with the single Mextral V10,resulting in larger synergistic shifts for zinc and cadmium with theΔpH_(50(Zn–Ca))values increasing substantially from0.83 to 1.73 pH units andΔpH_(50(Cd–Ca))values increasing from 0.63 to 2.13 p H units.The aqueous to organic ratio(A/O ratio),the saponification ratio of Mextral V10 and extracting agent concentration were studied on the effect of metal ions extraction,which helped to increase the organic capacity of metal extraction.The Mc Cabe-Thiele plot for Cd and Zn extraction with 5%(volume fraction)Mextral V10 and 5%Mextral 622H extractants mixture indicate the necessity of only one theoretical stages at an A/O ratio of 1.5:1.One stage extraction simulation test conducted at pH 6.50 shows that Cd and Zn reach the extraction of 99.6%and 97.9%,respectively,and only low levels of magnesium and calcium are extracted in the organic phase.The extracted Zn^(2+)or Cd^(2+)-organic species are Zn(A_1)(A_2)or Cd(A_1)(A_2)with the mixture system by slope analysis.
文摘A new kind of polyacrylamide derivate, hydroximic polyacrylamide (HPAM), was prepared from polyacrylamide (PAM) with hydroxylamine hydrochloride in KOH/alcohol solution. Based on colorimetric method in the measurement of C 7 9 alkyl hydroximic acid, the substitution degree of HPAM was determined by selecting octyl hydroximic acid as a primary standard substance. The effects of temperature, the amount of hydroxylamine and potassium hydroxide, and the reaction time on the reaction are discussed. HPAM with 5.78% substitution of degree was acquired by optimizing the reaction conditions. IR spectra revealed that tautomerism appears in the HPAM, and that HPAM exists in both the forms of hydroxamic type and hydroximic type, and the latter type can easily lead to the forming of intramolecular hydrogen bond.
基金the National Research Foundation of Korea(NRF)and funded by the Ministry of Education(No.2018R1A6A1A03025582)the National Research Foundation of Korea(NRF-2019R1D1A3A03103828).
文摘Periodontitis is a type of chronic inflammation in the gingival tissue caused by infectious bacteria colonizing the surface of the teeth,leading to the destruction of tooth-supporting tissues and loss of alveolar bone.Suberoylanilide hydroxamic acid(SAHA),a class of histone deacetylase(HDAC)inhibitor,has the potential to stimulate osteoblast differentiation by acetylating histone proteins,and thus suppressing the expression of adipogenic and chondrogenic genes.However,the effect of SAHA on the differentiation of human periodontal ligament stem cells(hPDLSCs)is yet to be elucidated.Herein,we investigated the effects of SAHA on in vitro proliferation and differentiation of hPDLSCs by MTT assay,Alizarin Red-S,and alkaline phosphatase staining,and real-time PCR.Notably,300 ng/mL SAHA treatment enhanced the proliferation and mineralization of hPDLSCs,indicating their osteogenic potential.Moreover,a significant enhancement of osteogenesis gene markers and proteins was observed.We also demonstrated that ERK is a positive regulator of Runx2 transcription factors during osteoblast differentiation.These results indicate that SAHA may be a useful osteogenic induction agent for periodontal bone regeneration.