Objective To investigate the application of BPDE-albumin adducts as monitoring biomarkers for coke oven workers exposed to polycyclic aromatic hydrocarbons (PAHs) and to explore possible relationship between BPDE-al...Objective To investigate the application of BPDE-albumin adducts as monitoring biomarkers for coke oven workers exposed to polycyclic aromatic hydrocarbons (PAHs) and to explore possible relationship between BPDE-albumin adducts and urinary 1-hydroxypyrene (1-OHP) levels in them. Methods Thirty-seven coke oven workers from a coke plant and 47 controls without the occupational exposure to PAHs were recruited in this study. The levels of plasma BPDE-albumin adducts and urinary 1-OHP were analyzed using high performance liquid chromatography. Results The median levels of BPDE-albumin adducts (42.10 fmol/mg albumin) and urinary 1-OHP (5.46 μmol/mol creatinine) were significantly higher in coke oven workers than in controls (14.16 fmol/mg albumin, 2.96μmol/mol creatinine, respectively; P〈0.01). Multiple logistic regression analysis showed that coke oven workers were at higher risk of having BPDE-albumin adduct levels above 25.30 μmol/mg albumin (OR=1.79, P〈0.01) and urinary 1-OHP levels above 4.13 μmol/mol creatinine (OR=2.45, P〈0.05). There was a positive correlation between the levels of BPDE-albumin adducts and urinary 1-OHP in all subjects (rs=0.349, P〈0.01). Conclusion BPDE-albumin adduct is a useful biomarker for monitoring long-term exposure to PAHs, and plasma BPDE-albumin adducts level is significantly correlated to urinary 1-OHP levels in coke oven workers.展开更多
A new Diels-Alder type adduct mongolicin G (1) and a new flavone 5'-(1", 1"-dimethylallyl)-5,7,2',4'-tetrahydroxyflavone (2) were isolated from the stem and root bark of Morus mongolica. Their structures we...A new Diels-Alder type adduct mongolicin G (1) and a new flavone 5'-(1", 1"-dimethylallyl)-5,7,2',4'-tetrahydroxyflavone (2) were isolated from the stem and root bark of Morus mongolica. Their structures were determined by spectroscopic analysis and chiroptical methods.展开更多
Objective: Aflatoxin B1 (AFB1), which can cause the formation of AFB1-DNA adducts, is a known human carcinogen. AFB1-exposure individuals with inherited susceptible carcinogen-metabolizing or repairing genotypes ma...Objective: Aflatoxin B1 (AFB1), which can cause the formation of AFB1-DNA adducts, is a known human carcinogen. AFB1-exposure individuals with inherited susceptible carcinogen-metabolizing or repairing genotypes may experience an increased risk of genotoxicity. This study was designed to investigate whether the polymorphisms of two genes, the metabolic gene Glutathione S-transferase M1 (GSTM1) and DNA repair gene x-ray repair cross-complementing group 3 (XRCC3), can affect the levels of AFB1-DNA adducts in Guangxi Population (n= 966) from an AFB1-exposure area. Methods: AFB1-DNA adducts were measured by ELISA, and GSTM1 and XRCC3 codon 241 genotypes were identified by PCR-RFLP. Results: The GSTM1-null genotype [adjusted odds ratio (OR) = 2.09; 95% confidence interval (CI) = 1.61-2.71] and XRCC3 genotypes with 241 Met alleles [i.e., XRCC3-TM and -MM, adjusted ORs (95% CI) were 1.43 (1.08-1.89) and 2.42 (1.13-5.22), respectively] were significantly associated with higher levels of AFB1-DNA adducts. Compared with those individuals who did not express any putative risk genotypes as reference (OR = 1), individuals featuring all of the putative risk genotypes did experience a significantly higher DNA-adduct levels (adjusted ORs were 2.87 for GSTM1-null and XRCC3-TM; 5.83 for GSTM1-null and XRCC3-MM). Additionally, there was a positive joint effect between XRCC3 genotypes and long-term AFB1 exposure in the formation of AFB1-DNA adducts. Conclusion: These results suggest that individuals with susceptible genotypes GSTM1-null, XRCC3-TM, or XRCC3-MM may experience an increased risk of DNA damage elicited by AFB1 exposure.展开更多
A novel supramolecular adduct 3(C 42H 42N 28O 14) 2·H 2O (1) was synthesized by mixing 2- and cucurbit uril in solution of hydrochloric acid. The crystal structure was determined by single crys...A novel supramolecular adduct 3(C 42H 42N 28O 14) 2·H 2O (1) was synthesized by mixing 2- and cucurbit uril in solution of hydrochloric acid. The crystal structure was determined by single crystal X-ray diffraction analysis. The crystal belongs to orthorhombic system and space group F dd2 with cell dimensions: a=4.705 33 (5) nm, b=7.153 80 (6) nm, c= 1.894 61 (2) nm, Z=16, V=63.7744 (11) nm3, D c= 1.534 g/cm3, μ=3.007 mm -1, F(000)=29 120, R 1= 0.070 7, wR 2=0.169 2. In crystal, the cucurb uril molecules form two zig-zag chains.展开更多
The B3LYP/6-31G^* level of theory was used to optimize trans-[Pt(NH3)(Am)G-L], where Am = quinoline or thiazole and L is chosen as the model for functional groups of peptide side chains, and for adenine and guani...The B3LYP/6-31G^* level of theory was used to optimize trans-[Pt(NH3)(Am)G-L], where Am = quinoline or thiazole and L is chosen as the model for functional groups of peptide side chains, and for adenine and guanine sites of DNA as the ultimate target of platinum anticancer drugs. Bond dissociating energy and stability energy of complexes are chosen to study detailedly thermodynamic character of possible difunctional adducts model. In order to investigate the influence of a polarizable environment on the energy of the Pt-L bond formation, we adopt a new bonding energy formula brought forward by Lippard and his coworkers: △H(Sol) = △H(SCF) + △G(Solv), which is quite appropriate to compare with what is found in experimental studies. Our calculated results demonstrate that N-containing ligands are more favored in view of thermodynamics both in gas phrase and in solution. However, it is worthly to be noted that addition of solvation free energies result in moderate correction of bonding energy in relative ordering, and the largest ones both present in imidazole ligand, not in guanine ligand. Finally, the nature of bond is analyzed in terms of partial charges distribution based on NBO population.展开更多
A convenient method has been developed toward the stereoselective synthesis of N-substituted benzotriazole derivatives under mild conditions. The good stereolectivity, high yields and the simple procedure make the pre...A convenient method has been developed toward the stereoselective synthesis of N-substituted benzotriazole derivatives under mild conditions. The good stereolectivity, high yields and the simple procedure make the present protocol attractive.展开更多
Water-soluble b-alanine C60 adducts were synthesized, and the scavenging ability to superoxygen anion radical O2- and hydroxyl radical.OH were studied by autoxidation of pyrogallol and chemiluminescence, respectively....Water-soluble b-alanine C60 adducts were synthesized, and the scavenging ability to superoxygen anion radical O2- and hydroxyl radical.OH were studied by autoxidation of pyrogallol and chemiluminescence, respectively. It was found thatβ-alanine C60 adducts showed an excellent efficiency in eliminating superoxygen anion radical and hydroxyl radical. The 50% inhibition concentration (IC50) for superoxygen anion radical and hydroxyl radical were 0.15 mg/mL and 0.048 mg/mL, respectively. The difference should be mainly attributed to the different scavenging mechanisms.展开更多
A new 2,2"-bipyridine adduct of bis(O,O'-di(2-phenylethyl)dithiophosphato) cadmium(II), [Cd{S2P(OCH2CH2Ph)2}2"bipy] (1, bipy -- 2,2"-bipyridine), was synthesized and characterized by elemental analyses, ...A new 2,2"-bipyridine adduct of bis(O,O'-di(2-phenylethyl)dithiophosphato) cadmium(II), [Cd{S2P(OCH2CH2Ph)2}2"bipy] (1, bipy -- 2,2"-bipyridine), was synthesized and characterized by elemental analyses, IR, UV-vis, 1H NMR, fluorescence spectroscopy, thermo-gravimetric analysis, and X-ray single-crystal diffraction. The crystal of 1 crystallizes in triclinic, space group P1 with a = 10.4607(19), b = 11.679(2), c = 18.480(3) A, a = 98.900(2), β = 103.321(2), ), = 91.779(2), V= 2165.2(7) A3, Dc = 1.447 g/cm3, Z = 2, C42H4404N2P2S4Cd, Mr = 943.37, F(000) = 968,μ = 0.814 mm-1, the final R = 0.0536 and wR = 0.1206 for 6275 observed reflections with 1 〉 2a(/) and R = 0.0690 and wR = 0.1339 for all data. The result shows that the Cd(1) centre is five-coordinated by two N and three S atoms in a highly distorted square pyramidal configuration. The C-H'"S hydrogen bonding interactions and a set of weak intermolecular r-r stacking between adjacent aromatic rings stabilize the structure and make 1 assemble into a 1D zig-zag chain. In addition, the antibacterial activities of 1 against Escherichia coli, Bacillus subtilis and Staphylococcus bacteria were also screened by disc diffusion method.展开更多
Two novel acid-base adducts,[H2L1^2+](Hpbda)2(1,L1 = 1,4-di(lH-imidazol-4-yl)benzene,H2pbda = 1,4-benzenedicarboxylic acid) and[H2L2^2+](NO3)2(2,L2 = l,4-di(l-carboxymethyl-imidazol-4-yl)benzene),have be...Two novel acid-base adducts,[H2L1^2+](Hpbda)2(1,L1 = 1,4-di(lH-imidazol-4-yl)benzene,H2pbda = 1,4-benzenedicarboxylic acid) and[H2L2^2+](NO3)2(2,L2 = l,4-di(l-carboxymethyl-imidazol-4-yl)benzene),have been prepared and characterized by single-crystal X-ray diffraction,IR spectroscopy and elemental analysis.Compound 1 crystallizes in monoclinic,space group P21/n with a = 5.3525(11),b = 9.1471(19),c = 19.314(4) ?,β = 92.342(3)°,V= 944.8(3) A°3,Z = 2,C16H16N6O(10),Mr = 452.35,Dc = 1.590 g/cm^3,μ = 0.135 mm^-1,S = 1.058,F(000) = 468,the final R = 0.0661 and wR = 0.1887 for 2298 observed reflections(I〉 2σ(I)).Compound 2 crystallizes in monoclinic,space group P21/c with a = 9.6923(10),b = 17.2950(17),c = 7.1880(7) ?,β =94.801(2)°,V= 1200.7(2)A°3,Z = 2,C(28)H(22)N4O8,Mr = 542.50,Dc = 1.501 g/cm^3,μ = 0.112 mm^-1,S= 1.060,F(000) = 564,the final R = 0.0394 and wR = 0.1017 for 2768 observed reflections(I 〉2σ(I)).In the title compounds,both of L1 and L2 ligands act as weak base to accept protons to exhibit diprotonated H2L1^2+ and H2L2^2+ form,which can effectively employ as hydrogen bonding donors to combine anion moieties to form binary adducts respectively.In the crystal packing diagram of two polymers,there exist extensive noncovalent interactions including charge-transfer interactions,C(N)-H…π and N-H…O,C-H…O,O-H…O hydrogen bonding interactions between co-crystal moieties which consolidate the structures of supramolecular polymers,thus generating three-dimensional(3D) frameworks.展开更多
Myrcauones A-D(1-4),four new phloroglucinol-terpene adducts were isolated from the leaves of Myrciaria cauliflora.Their structures with absolute configurations were elucidated by combination of spectroscopic analysis,...Myrcauones A-D(1-4),four new phloroglucinol-terpene adducts were isolated from the leaves of Myrciaria cauliflora.Their structures with absolute configurations were elucidated by combination of spectroscopic analysis,single crystal X-ray diffraction,and electronic circular dichroism(ECD)calculations.Compound 1 was a rearranged isobutylphloroglucinol-pinene adduct featuring an unusual 2,3,4,4a,10,11-hexahydro-1H-3,11a-methanodibenzo[b,f]oxepin backbone.Compound 4 showed moderate antibacterial activity against Gram-positive bacteria including multiresistant strains.展开更多
Low levels (ng/g) of musk ketone (MK),used as a fragrance additive in the formulation of personal care products,are frequently detected in the water and other environment.Thus,aquatic organisms can be continuously exp...Low levels (ng/g) of musk ketone (MK),used as a fragrance additive in the formulation of personal care products,are frequently detected in the water and other environment.Thus,aquatic organisms can be continuously exposed to MK.In this study,kinetics and dose-response assessments of 2-amino-MK (AMK) metabolite,bound to cysteine-hemoglobin (Hb) in rainbow trout,formed by enzymatic nitro-reduction of MK have been demonstrated.Trout were exposed to a single exposure of 0.010,0.030,0.10,and 0.30 mg MK/g fish.Tw...展开更多
Musk xylene(MX) is frequently used as fragrances in formulation of personal care products. Quantification of a bound 4-amino- MX(4-AMX) as cysteine adducts in trout hemoglobin(Hb) was made by gas chromatography-...Musk xylene(MX) is frequently used as fragrances in formulation of personal care products. Quantification of a bound 4-amino- MX(4-AMX) as cysteine adducts in trout hemoglobin(Hb) was made by gas chromatography-ion trap-mass spectrometry(GC/MS). The Hb samples were collected from trout after 24 h exposure to MX at 10μg/g, and or menhaden oil(control). The formation of cysteine-Hb adduct was observed from nitroso derivative of MX, released by alkaline hydrolysis. The released 4-AMX metabolite was extracted in n- hexane. The extract was then reduced by evaporation, and analyzed by GC/MS. When similar agreement of mass spectral features and retention time of 4-AMX were obtained in both standard and sample solutions, the presence of 4-AMX metabolite in the Hb was confirmed. The concentration of 4-AMX was found to be 3.1 × 10^-6 6.9 × 10^-6 mg/g in the Hb solution. Quantitation was made based on an internal standard, a calibration plot, and response factor. In the non-hydrolyzed and laboratory blank extracts, the 4-AMX metabolite was not detected. Additionally, coeluting and interfefing ions were observed in the biological samples.展开更多
Aristolochic acid (AA) is a known nephrotoxin and potential carcinogen, which can form covalent DNA adducts after metabolic activation in vivo and in vitro. A simple method for preparation and characterization of ar...Aristolochic acid (AA) is a known nephrotoxin and potential carcinogen, which can form covalent DNA adducts after metabolic activation in vivo and in vitro. A simple method for preparation and characterization of aristolochic acid-DNA adducts was developed. Four AA-adducts were synthesized by a direct reaction of AAI/AAII with 2′-deoxynucleosides. The reaction mixture was first cleaned-up and pre-concentrated using solid phase extraction (SPE), and further purified by a reversed-phase high performance liquid chromatography (HPLC). By the application of developed SPE procedure, matrices and byproducts in reaction mixture could be greatly reduced and adducts of high purity (more than 94% as indicated by HPLC) were obtained. The purified AA-DNA adducts were identified and characterized with liquid-electrospray ionization-quadrupole-time of flight-mass spectrometry (LC-ESI-Q-TOF-MS/MS) and LC-Diode array detector-fluorescence (LC-DAD-FL) analysis. This work provides a robust tool for possible large-scale preparation of AA-DNA adduct standards, which can promote the further studies on carcinogenic and mutagenic mechanism of aristolochic acids.展开更多
Objective This paper aims to elucidate the combined toxicity of magnetite nanoparticles/Chromium [MNPs/Cr(Ⅵ)] adducts. Methods The HEK293 cell was exposed to either Cr(Ⅵ) or MNPs, or their adducts MNPs/Cr(Ⅵ)....Objective This paper aims to elucidate the combined toxicity of magnetite nanoparticles/Chromium [MNPs/Cr(Ⅵ)] adducts. Methods The HEK293 cell was exposed to either Cr(Ⅵ) or MNPs, or their adducts MNPs/Cr(Ⅵ). The cytotoxicity was evaluated by assessing the cell viability, apoptosis, oxidative stress induction, and cellular uptake. Results The toxicity of formed adducts is significantly reduced when compared to Cr(Ⅵ) anions. We found that the cellular uptake of MNPs/Cr(Ⅵ) adduct was rare, only few particles were endocytosed from the extracellular fluid and not accumulated in the cell nucleus. On the other hand, the Cr(Ⅵ) anions entered cells, generated oxidative stress, induced cell apoptosis, and caused cytotoxicity. Conclusion The results showed minor effects of the nanoadducts on the tested cells and supported that magnetite nanoparticles could be implemented in the wastewater treatment process in which advantageous properties outweigh the risks.展开更多
New podand compound 1,2 bis (8′ quinolyloxy ethoxy) benzene (BQEB) was prepared. A lanthanum adduct with BQEB was synthesized and its structure was characterized by X ray crystal analysis using Mo Kα radiation ( ...New podand compound 1,2 bis (8′ quinolyloxy ethoxy) benzene (BQEB) was prepared. A lanthanum adduct with BQEB was synthesized and its structure was characterized by X ray crystal analysis using Mo Kα radiation ( λ =0 071073 nm). Crystal data: space group C2/c, Z=4, a =1 8636(3) nm, b =2 0036(3) nm, c =1 5186(3) nm, α =90 00°, β =91 452(14)°, γ =90 00°, R f=0 0373 for 6520 observed data. In the crystal structure the La 3+ is ten coordinated by three NO - 3 and four H 2O. Two podand molecules link to the coordination core via O—H…N (average O…N=0 2766(3) nm) hydrogen bonds. The adduct has a one dimensional chain sandwich structure consisting of every two podand molecules with a [La(NO 3) 3·4H 2O] as a bridge. The whole crystal is packed in a manner of…LLMLLMLL….展开更多
Strong room-temperature photoluminescence from the adducts of C60 reacting with five different aliphatic amines, namely propylethylamine (PPA), n-butyl amine (BTA), n-heptylamine (HPA) and dodecylamine (DDA) and dieth...Strong room-temperature photoluminescence from the adducts of C60 reacting with five different aliphatic amines, namely propylethylamine (PPA), n-butyl amine (BTA), n-heptylamine (HPA) and dodecylamine (DDA) and diethylamine (DEA), was firstly found from their toluene solution at relatively shorter wavelength around 519 nm.The fluorescence intensity has a good correlation with the length of n-alkyl group chain, the steric position and concentration of different amines and setting of solution as well as the UV-radiation. Their fluorescence quenching by concentration and by aromatic electron-donor N,N-dimethylaniline (DMA) were first investigated and determined.展开更多
The B3LYP/6-31G^* level of theory was used for the optimization of nonclassical platinum drugs with planar aromatic heterocycle ligands in addition to their monoaqua species, diaqua species and monofunctional adducts...The B3LYP/6-31G^* level of theory was used for the optimization of nonclassical platinum drugs with planar aromatic heterocycle ligands in addition to their monoaqua species, diaqua species and monofunctional adducts. Single point calculations were performed on optimized geometries using the MP2/6-31G^** method, and the Lanl2dz pseudo potential for the Pt atom remained constant in all calculations. It can be easily seen that the trans effect can influence both geometrical structures and bond dissociating energies (BDEs). On the basis of our calculation, we get that the long-lived monofunctional adducts with chloride ligand may be in existence, because they possessed higher stability energies, easily dissociated chloride compared with the monoaqua species dissociating chloride and that replacement of the first chloride by bases became exothermic in solution. Our calculated results also demonstrate that the strongest H-bonds appear in the complexes of q-wG and t-wG using different methods. In comparison with adenine complexes, the corresponding guanine complexes possess larger interaction energies as well as higher stability energies either corrected by basis set superposition error (bsse) of Boys-Bernardi counterpoise method or uncorrected both in gas phase and in solution with one exception that the stability energy of q-CIA complex in solution is larger than that of q,CIG complex. Finally, the nature of bond was analyzed in terms of partial charges distribution based on NBO population.展开更多
An assay was described for measures of adducts of styrene oxide (SO) with molecules of hemoglobin(Hb) which have been modified at residues containing either carboxylic acid or sulfhydryl groups. The method employs tw...An assay was described for measures of adducts of styrene oxide (SO) with molecules of hemoglobin(Hb) which have been modified at residues containing either carboxylic acid or sulfhydryl groups. The method employs two steps. In the first, SO carboxylic acid adducts are hydrolyzed in basic medium to liberate styrene glycol(SG). Then, the remaining residues are reacted with a reductive catalyst (Raney nickel) to liberate the two positional isomers of SO cysteine adducts, i.e., 1 phenylethanol (1 PE) and 2 phenylethanol (2 PE). The liberated products are derivatized with pentafluorobenzoyl chloride and measured by GC NICI MS. The assay was evaluated with SO adducts of Hb which had been produced in the blood of Sprague Dawley rats following (a) in vitro modification(0—300m mol/L SO) or (b) i.p administration of either SO(0—1 mmol/kg) or styrene (0—3 mmol/kg). Levels of each of the three analytes (SG, 1 PE, and 2 PE) increased with dose in hemoglobin. The ratios of cysteine adducts to carboxylic acid adducts varied significantly among experiments. Ratios of 2 PE to 1 PE were much more consistent (2 PE/1 PE=6.9 (SE=1.5)) suggesting that binding of SO to cysteine residues of blood proteins is greatly preferred at the α position rather than the β position both in vitro and in vivo. The lowest detectable adduct concentration, using 10 mg of protein, was 8 pmol/g protein for SG,5 pmol/g protein for 1 PE, and 0.6 pmol/g protein for 2 PE. No significant change of adduct level was found during storage of proteins at -80℃ for 1 year.展开更多
基金This study was supported by National Key Basic Research and Development Program of China (No.2002CB512905)National Natural Science Foundation of China (No.30371204).
文摘Objective To investigate the application of BPDE-albumin adducts as monitoring biomarkers for coke oven workers exposed to polycyclic aromatic hydrocarbons (PAHs) and to explore possible relationship between BPDE-albumin adducts and urinary 1-hydroxypyrene (1-OHP) levels in them. Methods Thirty-seven coke oven workers from a coke plant and 47 controls without the occupational exposure to PAHs were recruited in this study. The levels of plasma BPDE-albumin adducts and urinary 1-OHP were analyzed using high performance liquid chromatography. Results The median levels of BPDE-albumin adducts (42.10 fmol/mg albumin) and urinary 1-OHP (5.46 μmol/mol creatinine) were significantly higher in coke oven workers than in controls (14.16 fmol/mg albumin, 2.96μmol/mol creatinine, respectively; P〈0.01). Multiple logistic regression analysis showed that coke oven workers were at higher risk of having BPDE-albumin adduct levels above 25.30 μmol/mg albumin (OR=1.79, P〈0.01) and urinary 1-OHP levels above 4.13 μmol/mol creatinine (OR=2.45, P〈0.05). There was a positive correlation between the levels of BPDE-albumin adducts and urinary 1-OHP in all subjects (rs=0.349, P〈0.01). Conclusion BPDE-albumin adduct is a useful biomarker for monitoring long-term exposure to PAHs, and plasma BPDE-albumin adducts level is significantly correlated to urinary 1-OHP levels in coke oven workers.
基金the National Natural Science Foundation of China(NO.20432030)for financial support.
文摘A new Diels-Alder type adduct mongolicin G (1) and a new flavone 5'-(1", 1"-dimethylallyl)-5,7,2',4'-tetrahydroxyflavone (2) were isolated from the stem and root bark of Morus mongolica. Their structures were determined by spectroscopic analysis and chiroptical methods.
基金supported by the National Natural Science Foundation of China (No.39860032)the Youth Science Foundation of Guangxi (No.0833097)
文摘Objective: Aflatoxin B1 (AFB1), which can cause the formation of AFB1-DNA adducts, is a known human carcinogen. AFB1-exposure individuals with inherited susceptible carcinogen-metabolizing or repairing genotypes may experience an increased risk of genotoxicity. This study was designed to investigate whether the polymorphisms of two genes, the metabolic gene Glutathione S-transferase M1 (GSTM1) and DNA repair gene x-ray repair cross-complementing group 3 (XRCC3), can affect the levels of AFB1-DNA adducts in Guangxi Population (n= 966) from an AFB1-exposure area. Methods: AFB1-DNA adducts were measured by ELISA, and GSTM1 and XRCC3 codon 241 genotypes were identified by PCR-RFLP. Results: The GSTM1-null genotype [adjusted odds ratio (OR) = 2.09; 95% confidence interval (CI) = 1.61-2.71] and XRCC3 genotypes with 241 Met alleles [i.e., XRCC3-TM and -MM, adjusted ORs (95% CI) were 1.43 (1.08-1.89) and 2.42 (1.13-5.22), respectively] were significantly associated with higher levels of AFB1-DNA adducts. Compared with those individuals who did not express any putative risk genotypes as reference (OR = 1), individuals featuring all of the putative risk genotypes did experience a significantly higher DNA-adduct levels (adjusted ORs were 2.87 for GSTM1-null and XRCC3-TM; 5.83 for GSTM1-null and XRCC3-MM). Additionally, there was a positive joint effect between XRCC3 genotypes and long-term AFB1 exposure in the formation of AFB1-DNA adducts. Conclusion: These results suggest that individuals with susceptible genotypes GSTM1-null, XRCC3-TM, or XRCC3-MM may experience an increased risk of DNA damage elicited by AFB1 exposure.
文摘A novel supramolecular adduct 3(C 42H 42N 28O 14) 2·H 2O (1) was synthesized by mixing 2- and cucurbit uril in solution of hydrochloric acid. The crystal structure was determined by single crystal X-ray diffraction analysis. The crystal belongs to orthorhombic system and space group F dd2 with cell dimensions: a=4.705 33 (5) nm, b=7.153 80 (6) nm, c= 1.894 61 (2) nm, Z=16, V=63.7744 (11) nm3, D c= 1.534 g/cm3, μ=3.007 mm -1, F(000)=29 120, R 1= 0.070 7, wR 2=0.169 2. In crystal, the cucurb uril molecules form two zig-zag chains.
基金This work was supported by the Science Foundation of Jinan University (639)
文摘The B3LYP/6-31G^* level of theory was used to optimize trans-[Pt(NH3)(Am)G-L], where Am = quinoline or thiazole and L is chosen as the model for functional groups of peptide side chains, and for adenine and guanine sites of DNA as the ultimate target of platinum anticancer drugs. Bond dissociating energy and stability energy of complexes are chosen to study detailedly thermodynamic character of possible difunctional adducts model. In order to investigate the influence of a polarizable environment on the energy of the Pt-L bond formation, we adopt a new bonding energy formula brought forward by Lippard and his coworkers: △H(Sol) = △H(SCF) + △G(Solv), which is quite appropriate to compare with what is found in experimental studies. Our calculated results demonstrate that N-containing ligands are more favored in view of thermodynamics both in gas phrase and in solution. However, it is worthly to be noted that addition of solvation free energies result in moderate correction of bonding energy in relative ordering, and the largest ones both present in imidazole ligand, not in guanine ligand. Finally, the nature of bond is analyzed in terms of partial charges distribution based on NBO population.
基金the National Natural Science Foundation of China (No. 20072033)Specialized Research Fund for the Doctoral Program of Higher Education of China.
文摘A convenient method has been developed toward the stereoselective synthesis of N-substituted benzotriazole derivatives under mild conditions. The good stereolectivity, high yields and the simple procedure make the present protocol attractive.
文摘Water-soluble b-alanine C60 adducts were synthesized, and the scavenging ability to superoxygen anion radical O2- and hydroxyl radical.OH were studied by autoxidation of pyrogallol and chemiluminescence, respectively. It was found thatβ-alanine C60 adducts showed an excellent efficiency in eliminating superoxygen anion radical and hydroxyl radical. The 50% inhibition concentration (IC50) for superoxygen anion radical and hydroxyl radical were 0.15 mg/mL and 0.048 mg/mL, respectively. The difference should be mainly attributed to the different scavenging mechanisms.
基金supported by the project of Science & Technology Department of Sichuan Province(2011JY0052,2010GZ0130)Sichuan University of Science & Engineering(2012PY04,2012PY14)University Key Laboratory of Green Chemistry of Sichuan Institutes of Higher Education(LZJ1103,LZJ1203)
文摘A new 2,2"-bipyridine adduct of bis(O,O'-di(2-phenylethyl)dithiophosphato) cadmium(II), [Cd{S2P(OCH2CH2Ph)2}2"bipy] (1, bipy -- 2,2"-bipyridine), was synthesized and characterized by elemental analyses, IR, UV-vis, 1H NMR, fluorescence spectroscopy, thermo-gravimetric analysis, and X-ray single-crystal diffraction. The crystal of 1 crystallizes in triclinic, space group P1 with a = 10.4607(19), b = 11.679(2), c = 18.480(3) A, a = 98.900(2), β = 103.321(2), ), = 91.779(2), V= 2165.2(7) A3, Dc = 1.447 g/cm3, Z = 2, C42H4404N2P2S4Cd, Mr = 943.37, F(000) = 968,μ = 0.814 mm-1, the final R = 0.0536 and wR = 0.1206 for 6275 observed reflections with 1 〉 2a(/) and R = 0.0690 and wR = 0.1339 for all data. The result shows that the Cd(1) centre is five-coordinated by two N and three S atoms in a highly distorted square pyramidal configuration. The C-H'"S hydrogen bonding interactions and a set of weak intermolecular r-r stacking between adjacent aromatic rings stabilize the structure and make 1 assemble into a 1D zig-zag chain. In addition, the antibacterial activities of 1 against Escherichia coli, Bacillus subtilis and Staphylococcus bacteria were also screened by disc diffusion method.
基金supported by the National Natural Science Foundation of China(No.21171040 and 21302019)the disguished organic project(2013JCJS01)
文摘Two novel acid-base adducts,[H2L1^2+](Hpbda)2(1,L1 = 1,4-di(lH-imidazol-4-yl)benzene,H2pbda = 1,4-benzenedicarboxylic acid) and[H2L2^2+](NO3)2(2,L2 = l,4-di(l-carboxymethyl-imidazol-4-yl)benzene),have been prepared and characterized by single-crystal X-ray diffraction,IR spectroscopy and elemental analysis.Compound 1 crystallizes in monoclinic,space group P21/n with a = 5.3525(11),b = 9.1471(19),c = 19.314(4) ?,β = 92.342(3)°,V= 944.8(3) A°3,Z = 2,C16H16N6O(10),Mr = 452.35,Dc = 1.590 g/cm^3,μ = 0.135 mm^-1,S = 1.058,F(000) = 468,the final R = 0.0661 and wR = 0.1887 for 2298 observed reflections(I〉 2σ(I)).Compound 2 crystallizes in monoclinic,space group P21/c with a = 9.6923(10),b = 17.2950(17),c = 7.1880(7) ?,β =94.801(2)°,V= 1200.7(2)A°3,Z = 2,C(28)H(22)N4O8,Mr = 542.50,Dc = 1.501 g/cm^3,μ = 0.112 mm^-1,S= 1.060,F(000) = 564,the final R = 0.0394 and wR = 0.1017 for 2768 observed reflections(I 〉2σ(I)).In the title compounds,both of L1 and L2 ligands act as weak base to accept protons to exhibit diprotonated H2L1^2+ and H2L2^2+ form,which can effectively employ as hydrogen bonding donors to combine anion moieties to form binary adducts respectively.In the crystal packing diagram of two polymers,there exist extensive noncovalent interactions including charge-transfer interactions,C(N)-H…π and N-H…O,C-H…O,O-H…O hydrogen bonding interactions between co-crystal moieties which consolidate the structures of supramolecular polymers,thus generating three-dimensional(3D) frameworks.
基金supported by the National Key R&D Program of China(No.2017YFC1703800)the Program for the National Natural Science Foundation of China(Nos.81822042,81630095)+2 种基金the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2017BT01Y036)Key-Area Research and Development Program of Guangdong Province(2020B1111110004)the High-performance Computing Platform of Jinan University.
文摘Myrcauones A-D(1-4),four new phloroglucinol-terpene adducts were isolated from the leaves of Myrciaria cauliflora.Their structures with absolute configurations were elucidated by combination of spectroscopic analysis,single crystal X-ray diffraction,and electronic circular dichroism(ECD)calculations.Compound 1 was a rearranged isobutylphloroglucinol-pinene adduct featuring an unusual 2,3,4,4a,10,11-hexahydro-1H-3,11a-methanodibenzo[b,f]oxepin backbone.Compound 4 showed moderate antibacterial activity against Gram-positive bacteria including multiresistant strains.
文摘Low levels (ng/g) of musk ketone (MK),used as a fragrance additive in the formulation of personal care products,are frequently detected in the water and other environment.Thus,aquatic organisms can be continuously exposed to MK.In this study,kinetics and dose-response assessments of 2-amino-MK (AMK) metabolite,bound to cysteine-hemoglobin (Hb) in rainbow trout,formed by enzymatic nitro-reduction of MK have been demonstrated.Trout were exposed to a single exposure of 0.010,0.030,0.10,and 0.30 mg MK/g fish.Tw...
文摘Musk xylene(MX) is frequently used as fragrances in formulation of personal care products. Quantification of a bound 4-amino- MX(4-AMX) as cysteine adducts in trout hemoglobin(Hb) was made by gas chromatography-ion trap-mass spectrometry(GC/MS). The Hb samples were collected from trout after 24 h exposure to MX at 10μg/g, and or menhaden oil(control). The formation of cysteine-Hb adduct was observed from nitroso derivative of MX, released by alkaline hydrolysis. The released 4-AMX metabolite was extracted in n- hexane. The extract was then reduced by evaporation, and analyzed by GC/MS. When similar agreement of mass spectral features and retention time of 4-AMX were obtained in both standard and sample solutions, the presence of 4-AMX metabolite in the Hb was confirmed. The concentration of 4-AMX was found to be 3.1 × 10^-6 6.9 × 10^-6 mg/g in the Hb solution. Quantitation was made based on an internal standard, a calibration plot, and response factor. In the non-hydrolyzed and laboratory blank extracts, the 4-AMX metabolite was not detected. Additionally, coeluting and interfefing ions were observed in the biological samples.
基金supported by the National Basic Research Program (973) of China (No. 2007CB407305,2008CB417201)the National High Technology Research and Development Program (863) of China (No.2007AA06A407)the National Natural Science Foundation of China (No. 20737003, 20621703, 20805057)
文摘Aristolochic acid (AA) is a known nephrotoxin and potential carcinogen, which can form covalent DNA adducts after metabolic activation in vivo and in vitro. A simple method for preparation and characterization of aristolochic acid-DNA adducts was developed. Four AA-adducts were synthesized by a direct reaction of AAI/AAII with 2′-deoxynucleosides. The reaction mixture was first cleaned-up and pre-concentrated using solid phase extraction (SPE), and further purified by a reversed-phase high performance liquid chromatography (HPLC). By the application of developed SPE procedure, matrices and byproducts in reaction mixture could be greatly reduced and adducts of high purity (more than 94% as indicated by HPLC) were obtained. The purified AA-DNA adducts were identified and characterized with liquid-electrospray ionization-quadrupole-time of flight-mass spectrometry (LC-ESI-Q-TOF-MS/MS) and LC-Diode array detector-fluorescence (LC-DAD-FL) analysis. This work provides a robust tool for possible large-scale preparation of AA-DNA adduct standards, which can promote the further studies on carcinogenic and mutagenic mechanism of aristolochic acids.
文摘Objective This paper aims to elucidate the combined toxicity of magnetite nanoparticles/Chromium [MNPs/Cr(Ⅵ)] adducts. Methods The HEK293 cell was exposed to either Cr(Ⅵ) or MNPs, or their adducts MNPs/Cr(Ⅵ). The cytotoxicity was evaluated by assessing the cell viability, apoptosis, oxidative stress induction, and cellular uptake. Results The toxicity of formed adducts is significantly reduced when compared to Cr(Ⅵ) anions. We found that the cellular uptake of MNPs/Cr(Ⅵ) adduct was rare, only few particles were endocytosed from the extracellular fluid and not accumulated in the cell nucleus. On the other hand, the Cr(Ⅵ) anions entered cells, generated oxidative stress, induced cell apoptosis, and caused cytotoxicity. Conclusion The results showed minor effects of the nanoadducts on the tested cells and supported that magnetite nanoparticles could be implemented in the wastewater treatment process in which advantageous properties outweigh the risks.
文摘New podand compound 1,2 bis (8′ quinolyloxy ethoxy) benzene (BQEB) was prepared. A lanthanum adduct with BQEB was synthesized and its structure was characterized by X ray crystal analysis using Mo Kα radiation ( λ =0 071073 nm). Crystal data: space group C2/c, Z=4, a =1 8636(3) nm, b =2 0036(3) nm, c =1 5186(3) nm, α =90 00°, β =91 452(14)°, γ =90 00°, R f=0 0373 for 6520 observed data. In the crystal structure the La 3+ is ten coordinated by three NO - 3 and four H 2O. Two podand molecules link to the coordination core via O—H…N (average O…N=0 2766(3) nm) hydrogen bonds. The adduct has a one dimensional chain sandwich structure consisting of every two podand molecules with a [La(NO 3) 3·4H 2O] as a bridge. The whole crystal is packed in a manner of…LLMLLMLL….
文摘Strong room-temperature photoluminescence from the adducts of C60 reacting with five different aliphatic amines, namely propylethylamine (PPA), n-butyl amine (BTA), n-heptylamine (HPA) and dodecylamine (DDA) and diethylamine (DEA), was firstly found from their toluene solution at relatively shorter wavelength around 519 nm.The fluorescence intensity has a good correlation with the length of n-alkyl group chain, the steric position and concentration of different amines and setting of solution as well as the UV-radiation. Their fluorescence quenching by concentration and by aromatic electron-donor N,N-dimethylaniline (DMA) were first investigated and determined.
基金This work was supported by the Science Foundation of Jinan University (639)
文摘The B3LYP/6-31G^* level of theory was used for the optimization of nonclassical platinum drugs with planar aromatic heterocycle ligands in addition to their monoaqua species, diaqua species and monofunctional adducts. Single point calculations were performed on optimized geometries using the MP2/6-31G^** method, and the Lanl2dz pseudo potential for the Pt atom remained constant in all calculations. It can be easily seen that the trans effect can influence both geometrical structures and bond dissociating energies (BDEs). On the basis of our calculation, we get that the long-lived monofunctional adducts with chloride ligand may be in existence, because they possessed higher stability energies, easily dissociated chloride compared with the monoaqua species dissociating chloride and that replacement of the first chloride by bases became exothermic in solution. Our calculated results also demonstrate that the strongest H-bonds appear in the complexes of q-wG and t-wG using different methods. In comparison with adenine complexes, the corresponding guanine complexes possess larger interaction energies as well as higher stability energies either corrected by basis set superposition error (bsse) of Boys-Bernardi counterpoise method or uncorrected both in gas phase and in solution with one exception that the stability energy of q-CIA complex in solution is larger than that of q,CIG complex. Finally, the nature of bond was analyzed in terms of partial charges distribution based on NBO population.
文摘An assay was described for measures of adducts of styrene oxide (SO) with molecules of hemoglobin(Hb) which have been modified at residues containing either carboxylic acid or sulfhydryl groups. The method employs two steps. In the first, SO carboxylic acid adducts are hydrolyzed in basic medium to liberate styrene glycol(SG). Then, the remaining residues are reacted with a reductive catalyst (Raney nickel) to liberate the two positional isomers of SO cysteine adducts, i.e., 1 phenylethanol (1 PE) and 2 phenylethanol (2 PE). The liberated products are derivatized with pentafluorobenzoyl chloride and measured by GC NICI MS. The assay was evaluated with SO adducts of Hb which had been produced in the blood of Sprague Dawley rats following (a) in vitro modification(0—300m mol/L SO) or (b) i.p administration of either SO(0—1 mmol/kg) or styrene (0—3 mmol/kg). Levels of each of the three analytes (SG, 1 PE, and 2 PE) increased with dose in hemoglobin. The ratios of cysteine adducts to carboxylic acid adducts varied significantly among experiments. Ratios of 2 PE to 1 PE were much more consistent (2 PE/1 PE=6.9 (SE=1.5)) suggesting that binding of SO to cysteine residues of blood proteins is greatly preferred at the α position rather than the β position both in vitro and in vivo. The lowest detectable adduct concentration, using 10 mg of protein, was 8 pmol/g protein for SG,5 pmol/g protein for 1 PE, and 0.6 pmol/g protein for 2 PE. No significant change of adduct level was found during storage of proteins at -80℃ for 1 year.