Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Thermodynamic and spectroscopic study on the binding of interaction anionic phthalocyanine with calf thymus DNA  [PDF]
Hamid Dezhampanah,Termeh Darvishzad,Mehrnaz Aghazadeh
Spectroscopy: An International Journal , 2011, DOI: 10.3233/spe-2012-0564
Abstract: The interaction between anionic form of copper (II) N,N',N",N'"-tetrasulfonated phthalocyanine Cu (tspc) and to calf thymus deoxyribonucleic acid (ct-DNA) is investigated by measuring UV-vis absorption and fluorescence spectroscopy in phosphate buffer. The binding constant and stoichiometry were determined by analysis of optical absorption spectra of phthalocyanine at various ct-DNA concentrations using SQUAD software. The static mode of fluorescence quenching of phthalocyanine by calf thymus deoxyribonucleic acid indicates the formation of a ground-state complex. The formation of ground-state complex is a spontaneous molecular interaction procedure in which outside groove binding through the formation of an axial bond between the base pairs of nucleotide and Cu in the central core of phthalocyanine.
Subpicosecond dynamics in calf-thymus DNA, in the presence of Zn2+ ions: A Raman spectroscopic study  [PDF]
Cristina M. Muntean,Ioan Bratu,Konstantinos Nalpantidis,Monica A. P. Purcaru
Spectroscopy: An International Journal , 2009, DOI: 10.3233/spe-2009-0384
Abstract: In this paper the Raman total half bandwidths of calf-thymus DNA vibrations have been measured as a function of Zn2
Rheology of dilute suspensions of vesicles and red blood cells  [PDF]
Victoria Vitkova,Maud-Alix Mader,Chaouqi Misbah,Thomas Podgorski
Physics , 2007,
Abstract: We present rheology experiments on dilute solutions of vesicles and red blood cells (RBC). Varying the viscosity ratio $\lambda$ between internal and external fluids, the microscopic dynamics of suspended objects can be qualitatively changed from tank-treading ($tt$) to tumbling ($tb$). We find that in the tt regime the viscosity $\eta$, decreases when $\lambda$ increases, in contrast with droplet emulsions and elastic capsule theories which are sometimes invoked to model RBC dynamics. At a critical $\lambda$ (close to the tt-tb transition) $\eta$ exhibits a minimum before it increases in the tb regime. This is consistent with a recent theory for vesicles. This points to the nontrivial fact that the cytoskeleton in RBC does not alter the qualitative evolution of $\eta$ and that, as far as rheology is concerned, vesicle models might be a better description.
Molecular relaxation processes in calf-thymus DNA, in the presence of Mn2+ and Na+ ions: A Raman spectroscopic study  [PDF]
Cristina M. Muntean,Ioan Bratu
Spectroscopy: An International Journal , 2008, DOI: 10.3233/spe-2008-0356
Abstract: In this paper the Raman total half bandwidths of calf-thymus DNA vibrations have been measured as a function of Mn2
Raman spectroscopic study on the subpicosecond dynamics in calf-thymus DNA, upon lowering the pH and in the presence of Mn2+ ions  [PDF]
Cristina M. Muntean,Ioan Bratu
Spectroscopy: An International Journal , 2008, DOI: 10.3233/spe-2008-0363
Abstract: In this paper the Raman total half bandwidths of calf-thymus DNA vibrations have been measured as a function of pH (3.45–6.4), in the presence of Mn2+ ions, respectively. The dependencies of the half bandwidths and of the global relaxation times, on DNA molecular subgroup structure and on pH, are reported. It is shown that changes in the subpicosecond dynamics of molecular subgroups in calf-thymus DNA can be monitored with Raman spectroscopy.

Huang Weiqun,Xue Xuanxian,He Hengyi,

环境科学学报 , 1986,
Abstract: The covalent binding of 3H] -labelled PBNA, a recently identified weak carcinogen, to calf thymus DNA was studied in an in vitro metabolizing system. There was a dose-response effect and a time-dependent linear increase of the binding. Sephadex G-15 chromatographic separation of enzymic hydrolysate from calf thymus DNA showed three peaks of radioactivity responded to the peaks of UV absorbance at 260nm. This implied that there was a covalent binding resulting in the formation of DNA-PBNA complex.
Spectrophotometric evaluation of the behavior of disperse red 1 dye in aqueous media and its interaction with calf thymus ds-DNA
Uliana, Carolina V.;Garbellini, Gustavo S.;Yamanaka, Hideko;
Journal of the Brazilian Chemical Society , 2012, DOI: 10.1590/S0103-50532012005000009
Abstract: uv-vis spectrophotometry was used to measure the solubility of disperse red 1 (dr1) dye in aqueous solutions, using different solvents and dispersants. the dye was quantified in water samples, and its interaction with calf thymus ds-dna was investigated. the results showed that the commercial dispersant fongranal? fb was suitable for the preparation of aqueous dr1 solutions. for the determination of dr1 in purified water, the limit of detection was 2.47 × 10-6 mol l-1, and the limit of quantification was 8.22 × 10-6 mol l-1. percentage recoveries of 91.2 and 103% were obtained for dr1 concentrations of 3.00 × 10-6 and 40.0 × 10-6 mol l-1, respectively. the recoveries achieved for dr1 present in tap and river water were in the range 85.9-113%. the interaction of dr1 with calf thymus dna was accompanied by hypochromic and hyperchromic effects, which were related to conformational changes and damage to the dna double helix.
DNA-Harmalol interaction: The effects of Harmalol on the solution structure of calf-thymus DNA studied by FTIR spectroscopy
Hadji Akhoondi A,Nafisi Sh,Diari H
DARU : Journal of Pharmaceutical Sciences , 2000,
Abstract: The interaction of hamalol with calf-thymus DNA was investigated at physiological pH with drug/DNA (phosphate) molar ratio(r) of 1/40. Fourier transform infrared difference spectroscopy were used to establish correlations between spectral changes and drug binding mode, sequence selectivity, DNA conformation and structural properties of harmalol-DNA complexes in aqueous solution. Spectroscopic results indicated that harmalol is a weak intercalator with affinity for A-T rich regions. At low drug concentration (r=1/40), the A-T region is the main target of drug intercalation.
The Immunomodulatory Role of Calf Thymus Extract on Humoral and Cell Mediated Immune Response in Chicken Vaccinated Against New Castle Disease Virus  [PDF]
B.M. Chandra Naik,Y. Hari Babu,G.S. Mamatha
International Journal of Poultry Science , 2005,
Abstract: The effect of administration of calf thymus extract (CTE) with protein concentration of 1.8mg/ml was studied using two groups of day old layer chicks. Both the groups were vaccinated with ‘F’ and ‘R2B’ strains of New Castle Disease Virus (NDV) vaccines on 7th day and 8th week respectively. One group was administered with 1.8mg of thymic proteins intraperitoneally, one week prior and one week after each vaccination. The other group remained as vaccinated control group. Humoral and cell mediated responses were evaluated 15 days after each vaccination. Intraperitoneal administration of calf thymus extract markedly and significantly increased the antibody titres against NDV, serum globulin level, and percentage of lymphocytes in the blood. In addition thymus extract resulted in definite and significant cellular immunopotentiation.
Site-specific mutagenesis of Drosophila proliferating cell nuclear antigen enhances its effects on calf thymus DNA polymerase δ
Dmitry Mozzherin, Maeve McConnell, Holly Miller, Paul A Fisher
BMC Biochemistry , 2004, DOI: 10.1186/1471-2091-5-13
Abstract: Drosophila PCNA, although highly similar in structure to mammalian PCNA (e.g., it is >70% identical to human PCNA in amino acid sequence), can only substitute poorly for either calf thymus or human PCNA (~10% as well) in affecting calf thymus pol δ. However, by mutating one or only a few amino acids in the region of Drosophila PCNA thought to interact with pol δ, all four effects can be enhanced dramatically.Our results therefore suggest that all four above effects depend at least in part on the PCNA-pol δ interaction. Moreover unlike mammals, Drosophila offers the potential for immediate in vivo genetic analyses. Although it has proven difficult to obtain sufficient amounts of homologous pol δ for parallel in vitro biochemical studies, by altering Drosophila PCNA using site-directed mutagenesis as suggested by our results, in vitro biochemical studies may now be performed using human and/or calf thymus pol δ preparations.Many Drosophila melanogaster homologs of the proteins required for both DNA replication and repair have been identified and in several cases purified to apparent homogeneity. These include DNA polymerase α holoenzyme [1,2], DNA polymerase δ(pol δ) [2-4], replication protein A (RP-A; [5]), replication factor C (RF-C; e.g., see [6-9]) and various origin recognition complex (ORC) subunits (see e.g., [10,11]). Moreover, complete replication of DNA containing the SV40 origin of replication has been reconstituted in vitro using purified SV40 T-antigen and Drosophila cell-free extracts [7].A protein about which much information has been obtained is proliferating cell nuclear antigen (PCNA). Drosophila PCNA was first identified both as a highly purified protein able to substitute, albeit poorly, for human PCNA in a cell-free SV40 DNA replication system reconstituted from purified proteins [12] and by Yamaguchi et al. [13] who used an oligonucleotide probe to detect the Drosophila PCNA cDNA and gene, express the protein in E. coli and deduce its complete am
Page 1 /100
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.