With a view to finding out precisely how small peptides recognize a particular binding site of DNA, we have accomplished DNA binding studies of two peptides, H-Tyr-Arg-OH (YR) and H-Gly-Gly-His-OH (GGH) by using measu...With a view to finding out precisely how small peptides recognize a particular binding site of DNA, we have accomplished DNA binding studies of two peptides, H-Tyr-Arg-OH (YR) and H-Gly-Gly-His-OH (GGH) by using measurements in comparison with the binding between DNA and Hoechst 33258. The inhibition mode by YR and GGH to DNA binding of Hoechst 33258 was analyzed by Lineweaver-Burk plot which shows the plot of typical competitive inhibition at concentration of Hoechst 33258 from 3.66 ( 10-9 mol / L to 1.09 ( 10-8 mol / L. And it is concluded that YR binds to DNA in its minor groove (AT rich regions) with a binding constant K = 1.02 ( 108 (mol / L)-1. The GGH(s specificity is reduced at high concentration because it can also bind GC base pair.展开更多
Two new copper complexes based on 2-naphthoxyacetic acid ligand, namely [Cu(L)2(CH3CN)]2(1) and [Cu(L)(1,10-phen)2](2), where L = 2-naphthoxyacetic acid and 1,10-phen = 1,10-phenanthroline, were obtained by hydrotherm...Two new copper complexes based on 2-naphthoxyacetic acid ligand, namely [Cu(L)2(CH3CN)]2(1) and [Cu(L)(1,10-phen)2](2), where L = 2-naphthoxyacetic acid and 1,10-phen = 1,10-phenanthroline, were obtained by hydrothermal reaction and characterized by single-crystal X-ray diffraction. The binuclear complex 1 and mononuclear complex 2 belong to space group C2/c and P■, respectively. The binding properties of the two compounds with ct-DNA were investigated by UV-Vis and fluorescence spectra. The two compounds could bind with ct-DNA through interactions. Compound 2 displays stronger binding ability in the reaction with ct-DNA.展开更多
Three novel rare earth complexes, [Ln2（DCA）2（phen）2]（NO3）2·6H2O （Ln（III）=Sm（III）（1）, Er（III）（2）, Yb（III）（3）; DCA2–=de-methylcantharate, 7-oxabicyclo[2.2.1] heptane-2,3-dicarboxylate, C8H8O52...Three novel rare earth complexes, [Ln2（DCA）2（phen）2]（NO3）2·6H2O （Ln（III）=Sm（III）（1）, Er（III）（2）, Yb（III）（3）; DCA2–=de-methylcantharate, 7-oxabicyclo[2.2.1] heptane-2,3-dicarboxylate, C8H8O52–; phen=1,10-phenanthroline, C12H8N2） were synthesized. The structures were characterized by elemental analysis, molar conductance, IR and TGA. The results suggested that the structural features of the complexes were： in each DCA2–, one carboxylate group, as bidentate bridging group, connected two rare earth ions; the other carboxylate group, as bidentate chelate group took part in the coordination with rare earth ion. And cyclic ether oxygen of DCA2– and nitrogen atoms of phen took part in the coordination. The probable coordination number was seven. The interaction of the complexes with DNA was studied by UV-spectra, fluorescence spectra and viscosity measurements. Following increasing the concentration of DNA, the UV absorption bands nearby 265 nm of the three complexes appeared hypochromism and red-shift phenomena. And the values of binding constants Kb were 1.89×105 L/mol （1）, 3.54×104 L/mol （2） and 3.83×104 L/mol （3）. The complexes could quench the fluorescence of EB-DNA system, and the values of equilibrium constants Ksq were 1.72（1）, 0.56（2） and 1.09（3）. The relative viscosity of DNA steadily decreased with increasing the concentration of complexes. So, we could infer that the complexes may partially insert into DNA. The study of agarose gel electrophoresis showed that the complexes could cleave plasmid DNA, and the process of the reaction was through unclassical redox mechanism.展开更多
A cobalt（11） complex containing mixed-ligands of 1,10-phenathroline（phen） and glycollic acid（GA）.｜Co（GA）_2（phen）｜ was synthesized and its structure was characterized by X-ray diffraction.The interaction of...A cobalt（11） complex containing mixed-ligands of 1,10-phenathroline（phen） and glycollic acid（GA）.｜Co（GA）_2（phen）｜ was synthesized and its structure was characterized by X-ray diffraction.The interaction of the complex with DNA was investigated by electronic absorption spectra and electrochemical methods.Electronic absorption spectrum experiments showed that after interaction with DNA.the characteristic absorption peaks of ｜Co（GA）_2（phen）｜ underwent hypochromic effect as well as redshift. Also,the binding strength of 3.8×10~4L/mol was estimated by titration method.Electrochemical assays revealed that the redox peak currents of the complex decreased obviously accompanied by a positive shift of the formal potential after association with DNA.All these results revealed that the synthesized cobalt complex bound with DNA via an intercalation mode.展开更多
DNA is the genetic material of various organisms. Extracellular DNA adsorbed or bound on surface-active particles in soils has been shown to persist for long periods against nucleases degradation and still retain the ...DNA is the genetic material of various organisms. Extracellular DNA adsorbed or bound on surface-active particles in soils has been shown to persist for long periods against nucleases degradation and still retain the ability to transform competent cells. This paper reviews some recent advances on the binding and transformation of extracellular DNA in soils, which is fundamental to understanding the nature of the soil, regulating biodiversity, and assessing the risk of releasing genetically engineered microo…展开更多
In this study, we compared conventional sperm selection with high-magnification morphology based on the motile sperm organellar morphology examination （MSOME） criteria, and hyaluronic acid （HA） binding for sperm c...In this study, we compared conventional sperm selection with high-magnification morphology based on the motile sperm organellar morphology examination （MSOME） criteria, and hyaluronic acid （HA） binding for sperm chromosome aneuploidy and DNA fragmentation rates. Semen from 50 severe male factor cases was processed through density gradient centrifugation, and subjected to sperm selection by using the conventional method （control）, high magnification at x6650 or HA binding. Aneuploidy was detected by fluorescence in situ hybridization with probes for chromosomes 13, 18, 21, X and Y, and DNA fragmentation by the terminal deoxynucleotidyl transferase dUTP nick end labelling （TUNEL） method. Spermatozoa selected under high-magnification had a lower DNA fragmentation rate （2.6% vs. 1.7%; P=0.032）, with no significant difference in aneuploidy rate （0.8% vs0.7%; P=0.583）, than those selected by the HA binding method. Spermatozoa selected by both methods had much lower aneuploidy and DNA fragmentation rate than the controls （7% aneuploidy and 26.8% DNA fragmentation rates, respectively）. In the high-magnification group, the aneuploidy rate was lower when the best spermatozoa were selected than when only the second-best spermatozoa were available for selection, but the DNA fragmentation rate was not different. In conclusion, sperm selection under high magnification was more effective than under HA binding in selecting spermatozoa with low DNA fragmentation rate, but the small difference （0.9%） might not be clinically meaningful. Both methods were better than the conventional method of sperm selection.展开更多
Two ligands 2,2＇-[2,3-naphthylenebis（oxy）]-bis（N-benzyl（acetamide））（L1） and 2,2＇-[2,3-naphthylenebis （oxy）]-bis（N,N-diphenyl （acetamide））（L2） and their europium（Ill） picrate complexes were synthesi...Two ligands 2,2＇-[2,3-naphthylenebis（oxy）]-bis（N-benzyl（acetamide））（L1） and 2,2＇-[2,3-naphthylenebis （oxy）]-bis（N,N-diphenyl （acetamide））（L2） and their europium（Ill） picrate complexes were synthesized. The complexes were characterized by elemental analysis, inf,- red （IR）, thermogravimetry and differential thermal analysis （TG-DTA） and molar conductivity. Fluorescent experiments showed that the resonance level of the Eu（III） matched better to the triplet state energy level of the ligand L2 than that of the ligand L1 and the fluorescence in- tensities of the complexes were reduced with the raising coordination ability of solvent. In addition, the interactions between the complexes and DNA were studied by means of spectrometry and cyclic voltammetry. The results suggested that the complexes could bind to DNA through intercalation and the complex 1 binded to DNA more strongly than the complex 2.展开更多
The binding of coordination compound Ru(phen) to calf thymus DNA andherring Aparm DNA has been investigated by absorption,emission and of circulardichroism,spectroscopy. Measurement ot enantioselectivily combvined w...The binding of coordination compound Ru(phen) to calf thymus DNA andherring Aparm DNA has been investigated by absorption,emission and of circulardichroism,spectroscopy. Measurement ot enantioselectivily combvined with photophysical experiment shows the bindins of Ru(phen),with calf thymus DNA is ofintercaiatively bound .mode but the binding of Ru(Phen),with herring spermDNA is of surface-bound mode.展开更多
Absorbance and fluorescence methods were used to study the interaction of - and A-tris (phenanthroline) nickel ( Ⅱ) complex with calf thymus DNA. It was con- cluded that -Ni(phen). preferentially bound to DNA. Espec...Absorbance and fluorescence methods were used to study the interaction of - and A-tris (phenanthroline) nickel ( Ⅱ) complex with calf thymus DNA. It was con- cluded that -Ni(phen). preferentially bound to DNA. Especially the fluorescence Scatchard plots were discussed for the binding of EthBr to calf thymus DNA in the presence of varying concentrations of the metal complex. Theses studies indicated that both the isomers bound to DNA by two acting types , namely , intercalative and electrostatic bound modes.展开更多
The binding of [Ru(bpy)2(IP)]2+(b2IP),[Ru(bpy)2(PIP)]2+(b2PIP),[Ru(Phen)2 (IP)]2+(p2IP),[Ru(phen)2(PIP)]2+(p2PIP) to calf thymus DNA was investigated using electronic absorption, circular dichroism and fluorescence em...The binding of [Ru(bpy)2(IP)]2+(b2IP),[Ru(bpy)2(PIP)]2+(b2PIP),[Ru(Phen)2 (IP)]2+(p2IP),[Ru(phen)2(PIP)]2+(p2PIP) to calf thymus DNA was investigated using electronic absorption, circular dichroism and fluorescence emission spectroscopies.CD spectra of dialyzates indicate enantioselectivity associated with binding.Evidence of intercalative binding is also provided by hypochromicity in the MLCT bands, increased emission intensities and curvature of emission quenching by [Fe (CN)6]4-. The total binding affinities seem to be in the order b2IP<b2PIP≤p2IP<p2PIP, which is consistent, with the order of ligand planarity. extent of aromtic πsystem and hydrophobicity, bpy<<phen<IP<PIP.展开更多
Two new ruthenium polypyridine complexes. L2RuL2+ where L=2,2'-bipyridine (bpy) and 2, 9-dimethyl-1. 10-phenanthroline (dmp); L' is Schiff base prepared from condensation of 4. 5 diazafluoren-9-one (AFO) and a...Two new ruthenium polypyridine complexes. L2RuL2+ where L=2,2'-bipyridine (bpy) and 2, 9-dimethyl-1. 10-phenanthroline (dmp); L' is Schiff base prepared from condensation of 4. 5 diazafluoren-9-one (AFO) and aniline. have been prepared and characterized by elemental analyses, electronic absorption, IR spectra. The binding of the complexes to calf thymus DNA has beeninvestics by absorption. emission spectra and circular dichroism spectroscopy. Experimental results show these two complexes bind to DNA by electrostatic mode and non-interactive binding mode.展开更多
A copper-bispyridylpyrrolide complex [Cu(PDPH)Cl](PDPH = 2,5-bis(2′-pyridyl)pyrrole) was synthesized and characterized. The complex crystallizes in the orthorhombic system with space group Pccn, a = 0.9016(3) nm, b =...A copper-bispyridylpyrrolide complex [Cu(PDPH)Cl](PDPH = 2,5-bis(2′-pyridyl)pyrrole) was synthesized and characterized. The complex crystallizes in the orthorhombic system with space group Pccn, a = 0.9016(3) nm, b = 1.0931(4) nm, c =2.5319(8) nm, and V = 2.4951(15) nm3. The copper center is situated in a square planar geometry. The interaction of the copper(II)complex with calf thymus DNA(CT-DNA) was investigated by electronic absorption, circular dichroism(CD) and fluorescence spectra. It is proposed that the complex binds to CT-DNA through groove binding mode. Nuclease activity of the complex was also studied by gel electrophoresis method. The complex can efficiently cleave supercoiled p BR322 DNA in the presence of ascorbate(H2A) via oxidative pathway. The preliminary mechanism of DNA cleavage by the complex with different inhibiting reagents indicates that the hydroxyl radicals were involved as the active species in the DNA cleavage process.展开更多
Inhibitor of DNA binding 2(Id2)can promote axonal regeneration after injury of the central nervous system.However,whether Id2 can promote axonal regeneration and functional recovery after peripheral nerve injury is cu...Inhibitor of DNA binding 2(Id2)can promote axonal regeneration after injury of the central nervous system.However,whether Id2 can promote axonal regeneration and functional recovery after peripheral nerve injury is currently unknown.In this study,we established a mouse model of bilateral sciatic nerve crush injury.Two weeks before injury,AAV9-Id2-3×Flag-GFP was injected stereotaxically into the bilateral ventral horn of lumbar spinal cord.Our results showed that Id2 was successfully delivered into spinal cord motor neurons projecting to the sciatic nerve,and the number of regenerated motor axons in the sciatic nerve distal to the crush site was increased at 2 weeks after injury,arriving at the tibial nerve and reinnervating a few endplates in the gastrocnemius muscle.By 1 month after injury,extensive neuromuscular reinnervation occurred.In addition,the amplitude of compound muscle action potentials of the gastrocnemius muscle was markedly recovered,and their latency was shortened.These findings suggest that Id2 can accelerate axonal regeneration,promote neuromuscular reinnervation,and enhance functional improvement following sciatic nerve injury.Therefore,elevating the level of Id2 in adult neurons may present a promising strategy for peripheral nerve repair following injury.The study was approved by the Experimental Animal Ethics Committee of Jinan University(approval No.20160302003)on March 2,2016.展开更多
A sensitive approach for the qualitative detection of DNA-binding protein on the microarray was developed. DNA complexes in which a partial duplex region is formed from a biotin-primer and a circle single strand DNA ...A sensitive approach for the qualitative detection of DNA-binding protein on the microarray was developed. DNA complexes in which a partial duplex region is formed from a biotin-primer and a circle single strand DNA （ssDNA） were spotted on a microarray. The endonuclease recognition site （ERS） and the DNA-binding sites （DBS） were arranged side by side within the duplex region. The working principle of the detection system is described as follows： when the DNA-binding protein capture the DBS, the endonuclease could not attach to the ERS, and the immobilized primer in the DNA complex could be extended along the circle ssDNA by rolling circle amplification （RCA）. When no protein protects the DBS, the ERS could be attacked by the endonuclease and subsequently no rolling circle amplification occurs. Thereby we can detect the sequence specific DNA-binding activity with high-sensitivity due to the signal amplification of RCA.展开更多
Novel trimers of triphenylethylene-coumarin hybrid containing two amino side chains （5a-d and 6a-d） were designed and synthesized by the condensation of 1,3,5-benzenetricarboxylic acid with the varied amino monomeri...Novel trimers of triphenylethylene-coumarin hybrid containing two amino side chains （5a-d and 6a-d） were designed and synthesized by the condensation of 1,3,5-benzenetricarboxylic acid with the varied amino monomeric hybrids catalyzed by HATU and DIPEA at room temperature. The extended trimeric compound 6a （R = piperidinyl） exhibited significant anti-proliferative activity against three cancer cells at IC5o of near 10 μmol/L. UV-vis, fluorescence （lifetime） and thermal denaturation exhibited that 6a had significant interaction with Ct-DNA by the intercalative mode of binding. The order of their anti- proliferative activities was 6（a, d） 〉 5（a, d） and （5-6）a 〉 （5-6）d, respectively, in accordance with that of their DNA binding properties, which suggested that the prolonged linker （six carbons） and piperidinyl ~roun on the side chains are beneficial to DNA binding and the anti-tumor activity.展开更多
Pancreatic cancer is one of the deadliest cancers with a very poor prognosis. Recently, there has been a significant increase in research directed towards identifying potential biomarkers that can be used to diagnose ...Pancreatic cancer is one of the deadliest cancers with a very poor prognosis. Recently, there has been a significant increase in research directed towards identifying potential biomarkers that can be used to diagnose and provide prognostic information for pancreatic cancer. These markers can be used clinically to optimize and personalize therapy for individual patients. In this review, we focused on 3 biomarkers involved in the DNA damage response pathway and the necroptosis pathway: Chromodomainhelicase-DNA binding protein 5, chromodomain-helicaseDNA binding protein 7, and mixed lineage kinase domain-like protein. The aim of this article is to review present literature provided for these biomarkers and current studies in which their effectiveness as prognostic biomarkers are analyzed in order to determine their future use as biomarkers in clinical medicine. Based on the data presented, these biomarkers warrant further investigation,and should be validated in future studies.展开更多
A series of novel pyrazole fused heterocyclic derivatives were synthesized via a two-step procedure or a one-pot two step method, and their catalytic DNA cleavage abilities and anti-BVDV activities were also evaluated...A series of novel pyrazole fused heterocyclic derivatives were synthesized via a two-step procedure or a one-pot two step method, and their catalytic DNA cleavage abilities and anti-BVDV activities were also evaluated. The results obtained indicated that compounds 3b-3c could catalyze the cleavage of supercoiled DNA （pUC 19 plasmid DNA） to nicked DNA under physiological conditions with high yields via a hydrolytic mechanism. The studies on anti-viral activities against bovine viral diarrhea virus （BVDV） demonstrated that some of the pyrazole derivatives showed pronounced anti-BVDV activity with interesting ECso values and no significant cytotoxicity. Among them, compound 31 showed the highest antiviral activity （ECso = 0.12 μmol/L） and was 10 fold more than that of the positive control ribavirin （ECso = 1.3 μmol/L）, which provided a potential candidate for the development of anti-BVDV agents.展开更多
Binding of cordycepin to the double helical DNA with a high affinity was investigated by CD spectra in this paper. The results proved that uncoiling, unbinding and denaturation of DNA proceeded continuously upon the i...Binding of cordycepin to the double helical DNA with a high affinity was investigated by CD spectra in this paper. The results proved that uncoiling, unbinding and denaturation of DNA proceeded continuously upon the increase of the concentration of cordycepin.展开更多
A new cobalt(Ⅱ) complex with tridentate ligand 2, 6-bis (benzimidazol- 2-yl)pyridine has been synthesized by microwave irradiation method and characterized by elemental analysis, electrochemical and spectral methods....A new cobalt(Ⅱ) complex with tridentate ligand 2, 6-bis (benzimidazol- 2-yl)pyridine has been synthesized by microwave irradiation method and characterized by elemental analysis, electrochemical and spectral methods. The binding of the complex with calf thymus DNA has also been investigated by absorption and fluorescence spectra.展开更多
文摘With a view to finding out precisely how small peptides recognize a particular binding site of DNA, we have accomplished DNA binding studies of two peptides, H-Tyr-Arg-OH (YR) and H-Gly-Gly-His-OH (GGH) by using measurements in comparison with the binding between DNA and Hoechst 33258. The inhibition mode by YR and GGH to DNA binding of Hoechst 33258 was analyzed by Lineweaver-Burk plot which shows the plot of typical competitive inhibition at concentration of Hoechst 33258 from 3.66 ( 10-9 mol / L to 1.09 ( 10-8 mol / L. And it is concluded that YR binds to DNA in its minor groove (AT rich regions) with a binding constant K = 1.02 ( 108 (mol / L)-1. The GGH(s specificity is reduced at high concentration because it can also bind GC base pair.
基金supported by the National Natural Science Foundation of China(21101090 and 21561021)
文摘Two new copper complexes based on 2-naphthoxyacetic acid ligand, namely [Cu(L)2(CH3CN)]2(1) and [Cu(L)(1,10-phen)2](2), where L = 2-naphthoxyacetic acid and 1,10-phen = 1,10-phenanthroline, were obtained by hydrothermal reaction and characterized by single-crystal X-ray diffraction. The binuclear complex 1 and mononuclear complex 2 belong to space group C2/c and P■, respectively. The binding properties of the two compounds with ct-DNA were investigated by UV-Vis and fluorescence spectra. The two compounds could bind with ct-DNA through interactions. Compound 2 displays stronger binding ability in the reaction with ct-DNA.
基金supported by the Natural Science Foundation of Zhejiang Province (Y407301)
文摘Three novel rare earth complexes, [Ln2（DCA）2（phen）2]（NO3）2·6H2O （Ln（III）=Sm（III）（1）, Er（III）（2）, Yb（III）（3）; DCA2–=de-methylcantharate, 7-oxabicyclo[2.2.1] heptane-2,3-dicarboxylate, C8H8O52–; phen=1,10-phenanthroline, C12H8N2） were synthesized. The structures were characterized by elemental analysis, molar conductance, IR and TGA. The results suggested that the structural features of the complexes were： in each DCA2–, one carboxylate group, as bidentate bridging group, connected two rare earth ions; the other carboxylate group, as bidentate chelate group took part in the coordination with rare earth ion. And cyclic ether oxygen of DCA2– and nitrogen atoms of phen took part in the coordination. The probable coordination number was seven. The interaction of the complexes with DNA was studied by UV-spectra, fluorescence spectra and viscosity measurements. Following increasing the concentration of DNA, the UV absorption bands nearby 265 nm of the three complexes appeared hypochromism and red-shift phenomena. And the values of binding constants Kb were 1.89×105 L/mol （1）, 3.54×104 L/mol （2） and 3.83×104 L/mol （3）. The complexes could quench the fluorescence of EB-DNA system, and the values of equilibrium constants Ksq were 1.72（1）, 0.56（2） and 1.09（3）. The relative viscosity of DNA steadily decreased with increasing the concentration of complexes. So, we could infer that the complexes may partially insert into DNA. The study of agarose gel electrophoresis showed that the complexes could cleave plasmid DNA, and the process of the reaction was through unclassical redox mechanism.
基金supported by the National Natural Science Foundation of China(No.20805041)Training Programme Foundation for Excellent Youth Researching Talents of Fujian's Universities(No.JA10201)+1 种基金Key Provincial University Project of Fujian(No.2008F5064)Research Foundation of Fujian Education Department (No.JA09170)
文摘A cobalt（11） complex containing mixed-ligands of 1,10-phenathroline（phen） and glycollic acid（GA）.｜Co（GA）_2（phen）｜ was synthesized and its structure was characterized by X-ray diffraction.The interaction of the complex with DNA was investigated by electronic absorption spectra and electrochemical methods.Electronic absorption spectrum experiments showed that after interaction with DNA.the characteristic absorption peaks of ｜Co（GA）_2（phen）｜ underwent hypochromic effect as well as redshift. Also,the binding strength of 3.8×10~4L/mol was estimated by titration method.Electrochemical assays revealed that the redox peak currents of the complex decreased obviously accompanied by a positive shift of the formal potential after association with DNA.All these results revealed that the synthesized cobalt complex bound with DNA via an intercalation mode.
文摘DNA is the genetic material of various organisms. Extracellular DNA adsorbed or bound on surface-active particles in soils has been shown to persist for long periods against nucleases degradation and still retain the ability to transform competent cells. This paper reviews some recent advances on the binding and transformation of extracellular DNA in soils, which is fundamental to understanding the nature of the soil, regulating biodiversity, and assessing the risk of releasing genetically engineered microo…
文摘In this study, we compared conventional sperm selection with high-magnification morphology based on the motile sperm organellar morphology examination （MSOME） criteria, and hyaluronic acid （HA） binding for sperm chromosome aneuploidy and DNA fragmentation rates. Semen from 50 severe male factor cases was processed through density gradient centrifugation, and subjected to sperm selection by using the conventional method （control）, high magnification at x6650 or HA binding. Aneuploidy was detected by fluorescence in situ hybridization with probes for chromosomes 13, 18, 21, X and Y, and DNA fragmentation by the terminal deoxynucleotidyl transferase dUTP nick end labelling （TUNEL） method. Spermatozoa selected under high-magnification had a lower DNA fragmentation rate （2.6% vs. 1.7%; P=0.032）, with no significant difference in aneuploidy rate （0.8% vs0.7%; P=0.583）, than those selected by the HA binding method. Spermatozoa selected by both methods had much lower aneuploidy and DNA fragmentation rate than the controls （7% aneuploidy and 26.8% DNA fragmentation rates, respectively）. In the high-magnification group, the aneuploidy rate was lower when the best spermatozoa were selected than when only the second-best spermatozoa were available for selection, but the DNA fragmentation rate was not different. In conclusion, sperm selection under high magnification was more effective than under HA binding in selecting spermatozoa with low DNA fragmentation rate, but the small difference （0.9%） might not be clinically meaningful. Both methods were better than the conventional method of sperm selection.
基金Project supported by National Natural Science Foundation of China (20962016)the Key Research Foundation of Education Ministry of China (208159)
文摘Two ligands 2,2＇-[2,3-naphthylenebis（oxy）]-bis（N-benzyl（acetamide））（L1） and 2,2＇-[2,3-naphthylenebis （oxy）]-bis（N,N-diphenyl （acetamide））（L2） and their europium（Ill） picrate complexes were synthesized. The complexes were characterized by elemental analysis, inf,- red （IR）, thermogravimetry and differential thermal analysis （TG-DTA） and molar conductivity. Fluorescent experiments showed that the resonance level of the Eu（III） matched better to the triplet state energy level of the ligand L2 than that of the ligand L1 and the fluorescence in- tensities of the complexes were reduced with the raising coordination ability of solvent. In addition, the interactions between the complexes and DNA were studied by means of spectrometry and cyclic voltammetry. The results suggested that the complexes could bind to DNA through intercalation and the complex 1 binded to DNA more strongly than the complex 2.
文摘The binding of coordination compound Ru(phen) to calf thymus DNA andherring Aparm DNA has been investigated by absorption,emission and of circulardichroism,spectroscopy. Measurement ot enantioselectivily combvined with photophysical experiment shows the bindins of Ru(phen),with calf thymus DNA is ofintercaiatively bound .mode but the binding of Ru(Phen),with herring spermDNA is of surface-bound mode.
文摘Absorbance and fluorescence methods were used to study the interaction of - and A-tris (phenanthroline) nickel ( Ⅱ) complex with calf thymus DNA. It was con- cluded that -Ni(phen). preferentially bound to DNA. Especially the fluorescence Scatchard plots were discussed for the binding of EthBr to calf thymus DNA in the presence of varying concentrations of the metal complex. Theses studies indicated that both the isomers bound to DNA by two acting types , namely , intercalative and electrostatic bound modes.
文摘The binding of [Ru(bpy)2(IP)]2+(b2IP),[Ru(bpy)2(PIP)]2+(b2PIP),[Ru(Phen)2 (IP)]2+(p2IP),[Ru(phen)2(PIP)]2+(p2PIP) to calf thymus DNA was investigated using electronic absorption, circular dichroism and fluorescence emission spectroscopies.CD spectra of dialyzates indicate enantioselectivity associated with binding.Evidence of intercalative binding is also provided by hypochromicity in the MLCT bands, increased emission intensities and curvature of emission quenching by [Fe (CN)6]4-. The total binding affinities seem to be in the order b2IP<b2PIP≤p2IP<p2PIP, which is consistent, with the order of ligand planarity. extent of aromtic πsystem and hydrophobicity, bpy<<phen<IP<PIP.
文摘Two new ruthenium polypyridine complexes. L2RuL2+ where L=2,2'-bipyridine (bpy) and 2, 9-dimethyl-1. 10-phenanthroline (dmp); L' is Schiff base prepared from condensation of 4. 5 diazafluoren-9-one (AFO) and aniline. have been prepared and characterized by elemental analyses, electronic absorption, IR spectra. The binding of the complexes to calf thymus DNA has beeninvestics by absorption. emission spectra and circular dichroism spectroscopy. Experimental results show these two complexes bind to DNA by electrostatic mode and non-interactive binding mode.
基金Project(21001118)supported by National Natural Science Foundation of ChinaProject(12JJ3016)supported by Natural Science Foundation of Hunan Province,China
文摘A copper-bispyridylpyrrolide complex [Cu(PDPH)Cl](PDPH = 2,5-bis(2′-pyridyl)pyrrole) was synthesized and characterized. The complex crystallizes in the orthorhombic system with space group Pccn, a = 0.9016(3) nm, b = 1.0931(4) nm, c =2.5319(8) nm, and V = 2.4951(15) nm3. The copper center is situated in a square planar geometry. The interaction of the copper(II)complex with calf thymus DNA(CT-DNA) was investigated by electronic absorption, circular dichroism(CD) and fluorescence spectra. It is proposed that the complex binds to CT-DNA through groove binding mode. Nuclease activity of the complex was also studied by gel electrophoresis method. The complex can efficiently cleave supercoiled p BR322 DNA in the presence of ascorbate(H2A) via oxidative pathway. The preliminary mechanism of DNA cleavage by the complex with different inhibiting reagents indicates that the hydroxyl radicals were involved as the active species in the DNA cleavage process.
基金This work was supported by the National Natural Science Foundation of China,Nos.82071369(to PY)and 81971198(to BZ)Guangdong grant‘Key Technologies for Treatment of Brain Disorders’of China,No.2018B030332001(to LZ and PY)+2 种基金Guangzhou Key Projects of Brain Science and Brain-Like Intelligence Technology,China,No.20200730090(to LZ)the Natural Science Foundation of Beijing of China,No.7192103(to BZ)the Clinical Innovation Research Program of Guangzhou Regenerative Medicine and Health Guangdong Laboratory of China,No.2018GZR0201006(to PY).
文摘Inhibitor of DNA binding 2(Id2)can promote axonal regeneration after injury of the central nervous system.However,whether Id2 can promote axonal regeneration and functional recovery after peripheral nerve injury is currently unknown.In this study,we established a mouse model of bilateral sciatic nerve crush injury.Two weeks before injury,AAV9-Id2-3×Flag-GFP was injected stereotaxically into the bilateral ventral horn of lumbar spinal cord.Our results showed that Id2 was successfully delivered into spinal cord motor neurons projecting to the sciatic nerve,and the number of regenerated motor axons in the sciatic nerve distal to the crush site was increased at 2 weeks after injury,arriving at the tibial nerve and reinnervating a few endplates in the gastrocnemius muscle.By 1 month after injury,extensive neuromuscular reinnervation occurred.In addition,the amplitude of compound muscle action potentials of the gastrocnemius muscle was markedly recovered,and their latency was shortened.These findings suggest that Id2 can accelerate axonal regeneration,promote neuromuscular reinnervation,and enhance functional improvement following sciatic nerve injury.Therefore,elevating the level of Id2 in adult neurons may present a promising strategy for peripheral nerve repair following injury.The study was approved by the Experimental Animal Ethics Committee of Jinan University(approval No.20160302003)on March 2,2016.
基金supported by the National Natural Science Foundation of China(Nos.60501010,60701008 and 60771024)
文摘A sensitive approach for the qualitative detection of DNA-binding protein on the microarray was developed. DNA complexes in which a partial duplex region is formed from a biotin-primer and a circle single strand DNA （ssDNA） were spotted on a microarray. The endonuclease recognition site （ERS） and the DNA-binding sites （DBS） were arranged side by side within the duplex region. The working principle of the detection system is described as follows： when the DNA-binding protein capture the DBS, the endonuclease could not attach to the ERS, and the immobilized primer in the DNA complex could be extended along the circle ssDNA by rolling circle amplification （RCA）. When no protein protects the DBS, the ERS could be attacked by the endonuclease and subsequently no rolling circle amplification occurs. Thereby we can detect the sequence specific DNA-binding activity with high-sensitivity due to the signal amplification of RCA.
基金the National Natural Science Foundation of China(NSFC,No.20902016)
文摘Novel trimers of triphenylethylene-coumarin hybrid containing two amino side chains （5a-d and 6a-d） were designed and synthesized by the condensation of 1,3,5-benzenetricarboxylic acid with the varied amino monomeric hybrids catalyzed by HATU and DIPEA at room temperature. The extended trimeric compound 6a （R = piperidinyl） exhibited significant anti-proliferative activity against three cancer cells at IC5o of near 10 μmol/L. UV-vis, fluorescence （lifetime） and thermal denaturation exhibited that 6a had significant interaction with Ct-DNA by the intercalative mode of binding. The order of their anti- proliferative activities was 6（a, d） 〉 5（a, d） and （5-6）a 〉 （5-6）d, respectively, in accordance with that of their DNA binding properties, which suggested that the prolonged linker （six carbons） and piperidinyl ~roun on the side chains are beneficial to DNA binding and the anti-tumor activity.
基金Supported by The National Center for Advancing Translational Sciences of the National Institutes of Health under award numbers ULl TR000454 previously awarded to Dr.Colbert and Dr.Fisher and TLlT R000456 to Dr.ColbertPancreatic Cancer Action Network(Pan-CAN)&sol American Association for Cancer Research(AACR)award 16982+1 种基金Department of Defense(DOD)/Peer Reviewed Cancer Research Program(PRCRP)award CA110535Georgia Cancer Coalition award 11072,all to Dr.Yu
文摘Pancreatic cancer is one of the deadliest cancers with a very poor prognosis. Recently, there has been a significant increase in research directed towards identifying potential biomarkers that can be used to diagnose and provide prognostic information for pancreatic cancer. These markers can be used clinically to optimize and personalize therapy for individual patients. In this review, we focused on 3 biomarkers involved in the DNA damage response pathway and the necroptosis pathway: Chromodomainhelicase-DNA binding protein 5, chromodomain-helicaseDNA binding protein 7, and mixed lineage kinase domain-like protein. The aim of this article is to review present literature provided for these biomarkers and current studies in which their effectiveness as prognostic biomarkers are analyzed in order to determine their future use as biomarkers in clinical medicine. Based on the data presented, these biomarkers warrant further investigation,and should be validated in future studies.
基金the National Natural Science Foundation of China (Nos.21105091 and 20772113) for the financial support
文摘A series of novel pyrazole fused heterocyclic derivatives were synthesized via a two-step procedure or a one-pot two step method, and their catalytic DNA cleavage abilities and anti-BVDV activities were also evaluated. The results obtained indicated that compounds 3b-3c could catalyze the cleavage of supercoiled DNA （pUC 19 plasmid DNA） to nicked DNA under physiological conditions with high yields via a hydrolytic mechanism. The studies on anti-viral activities against bovine viral diarrhea virus （BVDV） demonstrated that some of the pyrazole derivatives showed pronounced anti-BVDV activity with interesting ECso values and no significant cytotoxicity. Among them, compound 31 showed the highest antiviral activity （ECso = 0.12 μmol/L） and was 10 fold more than that of the positive control ribavirin （ECso = 1.3 μmol/L）, which provided a potential candidate for the development of anti-BVDV agents.
文摘Binding of cordycepin to the double helical DNA with a high affinity was investigated by CD spectra in this paper. The results proved that uncoiling, unbinding and denaturation of DNA proceeded continuously upon the increase of the concentration of cordycepin.
文摘A new cobalt(Ⅱ) complex with tridentate ligand 2, 6-bis (benzimidazol- 2-yl)pyridine has been synthesized by microwave irradiation method and characterized by elemental analysis, electrochemical and spectral methods. The binding of the complex with calf thymus DNA has also been investigated by absorption and fluorescence spectra.
