Abstract:
:Reactive oxygen species (ROS) have generated a great deal of interest in the clinical field since experimental studies showed the involvement of these species in carcinogenesis. This paper reports the detection of ROS during the decomposition of H2O2 in the presence of samples obtained from tissues of 16 patients with rectal carcinoma (age 64 +/- 9 years) operated on in the Division of Surgical Oncology of Pomeranian Medical University, Szczecin (Poland). The samples were cut from the middle of the resected tumors and from the colonic mucosa (10 cm distant from the tumor and free of disease); they were processed and the supernatants, representing the soluble fraction, were used for measurements. Various methods for measuring free radical activity of the examined samples were used, such as chemiluminescence, fluorescent probe 2',7'-dichlorodihydrofluorescein, spin trap 5,5-dimethyl-pyrroline-1-oxide and EPR, the spectrophotometrically examined formation of diformazan during reduction of the p-nitroblue tetrazolium salt, and bleaching of p-nitrosodimethylalanine. A statistically significant difference (P < 0.001) was noticed in mean chemiluminescence +/- standard error of the mean in the presence of the tumor samples (42.6 +/- 7.3) in comparison to the control samples (234.6 +/- 36.0). Significantly decreased generation of ROS from the decomposition of H2O2 in the presence of the tumor samples in comparison to the control samples was also observed when the above-mentioned methods were used. Tumor samples had significantly lower superoxide dismutase activity (33 +/- 4 U/mg protein) than controls (93 +/- 14 U/mg, P < 0.001), which should contribute to a lower capacity of endogenous H2O2 production and therefore less ROS generation upon H2O2 decomposition. We conclude that the tested samples have different redox properties; this supports a possible role of ROS activity during carcinogenesis. Moreover, we propose a new, simple, and sensitive chemiluminescent method, which might be effective in sample differentiation.
journal_name
Biopolymersjournal_title
Biopolymersauthors
Kładny J,Lichszteld K,Kołecki Jdoi
10.1002/bip.20068subject
Has Abstractpub_date
2004-08-05 00:00:00pages
413-21issue
5eissn
0006-3525issn
1097-0282journal_volume
74pub_type
杂志文章相关文献
BIOPOLYMERS文献大全abstract::The equilibrium structural ensemble of a 20-residue polyglutamic acid peptide (E(20)) was studied with FRET, circular dichroism, and molecular dynamics (MD) simulations. A FRET donor, o-aminobenzamide, and acceptor, 3-nitrotyrosine, were introduced at the N- and C-termini, respectively. Circular dichroism, steady stat...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.20719
更新日期:2007-06-15 00:00:00
abstract::Intermolecular NOE experiments have been used to explore interactions of water and ethanol molecules in 35% ethanol/65% water (v/v) with the peptide Trp-cage at temperatures from 5 to 25 degrees C. Magnetic dipole-dipole cross-relaxation terms sigma(HH) (NOE) and sigma(HH) (ROE) for interaction of solvent components w...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.21028
更新日期:2008-10-01 00:00:00
abstract::The 83-residue conopeptide (p21a) and its corresponding nonhydroxylated analog were isolated from the injected venom of Conus purpurascens. The complete conopeptide sequences were derived from Edman degradation sequencing of fragments from tryptic, chymotryptic and cyanogen bromide digestions, p21a has a unique, 10-cy...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.21406
更新日期:2011-01-01 00:00:00
abstract::The de novo design of peptides and proteins has emerged as an approach for investigating protein structure and function. The success relies heavily on the ability to design relatively short peptides that can adopt stable secondary structures. To this end, substitution with α,β-dehydroamino acids, especially α,β-didehy...
journal_title:Biopolymers
pub_type: 杂志文章,评审
doi:10.1002/bip.21561
更新日期:2011-03-01 00:00:00
abstract::Synthesis and CD and (13)C(alpha)-NMR studies in a near-neutral saline buffer are reported for a 65-residue peptide ((190)Tm(254)) comprising residues 190-254 of the alpha-tropomyosin chain. CD on a version disulfide cross-linked via the N-terminal cysteine side chains indicates that this dimer is highly helical and m...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/1097-0282(20011005)59:4<257::AID-BIP1022>3
更新日期:2001-10-05 00:00:00
abstract::The coupling of nuC-O and deltaO-D vibrations in the 1200-900 cm(-1) IR range leads to band shifting in opposite directions, which provides information on intramolecular hydrogen bonding of carbohydrates in aqueous solution. The aqueous solution IR spectra of 2-acetamide-1,6-anhydro-2-deoxy-D-glucopyranose and cis-1,2...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.10024
更新日期:2002-01-01 00:00:00
abstract::G protein-coupled receptor kinase 2 (GRK2) plays a central role in the cellular transduction network. In particular, during chronic heart failure GRK2 is upregulated and believed to contribute to disease progression. Thereby, its inhibition offers a potential therapeutic solution to several pathological conditions. In...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.22295
更新日期:2014-01-01 00:00:00
abstract::It is becoming increasingly clear that characterization of the protein ensemble-the collection of all conformations of which the protein is capable-will be a critical step in developing a full understanding of the linkage between structure, dynamics, and function. X-ray solution scattering in the small angle (SAXS) an...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.21631
更新日期:2011-08-01 00:00:00
abstract::The structural evolution of regenerated Bombyx mori silk fibroin during shearing with a Couette cell has been studied in situ by synchrotron radiation small- and wide-angle x-ray scattering techniques. An elongation of fibroin molecules was observed with increasing shear rate, followed by an aggregation phase. The agg...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.20083
更新日期:2004-07-01 00:00:00
abstract::Depsipeptide analogues of peptide sequences can help in elucidating the role of specific hydrogen bonds in determining the conformation in peptides. The repeating pentapeptide and hexapeptide sequences of elastin have been suggested to contain a type II beta-turn with a 4----1 hydrogen bond. Depsipeptide analogues of ...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.360291212
更新日期:1990-10-01 00:00:00
abstract::Adrenocorticotropin (ACTH) (1-10), an adrenocorticotropin hormone fragment, has been studied by molecular dynamics (MD) simulation in an NPT ensemble in an explicit dodecylphosphocholine (DPC) micelle. Two starting configurations of the peptide/micelle system, corresponding to the insertion and surface-binding modes, ...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/1097-0282(200106)58:7<643::AID-BIP1037>3.0
更新日期:2001-06-01 00:00:00
abstract::We applied dynamic light scattering technique on the model system of hen egg lysozyme in salt-free aqueous ethanol solution to study the mechanism of denaturation and aggregation of protein. At low ethanol concentration [0-63% (v/v)], the fast relaxation mode was observed, which was caused by lysozyme molecules in the...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/1097-0282(20011015)59:5<370::AID-BIP1034>3
更新日期:2001-10-15 00:00:00
abstract::Decomposition of CD spectra for the unfolding of both coiled-coil and single-helical molecules is carried out via the convex constraint algorithm (CCA) [A. Perczel, M. Hollósi, G. Tusnády, and G. D. Fasman (1991) Protein Engineering, Vol. 4, pp. 669-679]. Examined are (1) our thermal unfolding data for rabbit alpha al...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.360360310
更新日期:1995-09-01 00:00:00
abstract::Infrared spectra of poly(D,L-alanine), poly(L-glutamic acid), poly(L-lysine), silk fibroin, and tropomyosin have been registered for various conformations of the polypeptide chain. Assuming additivity of the main- and side-chain absorption, spectral parameters of amide I and II absorption bands corresponding to alpha-...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.360301310
更新日期:1990-01-01 00:00:00
abstract::The kinetics of the hydrodynamic volume change associated with the unfolding and refolding of a globular protein can be observed using high performance size exclusion chromatography. Chromatographic profiles that evidence such dynamics can be simulated using equations in which chromatographic partitioning and the conf...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.360330113
更新日期:1993-01-01 00:00:00
abstract::In the past two decades, keratin biomaterials have shown impressive results as scaffolds for tissue engineering, wound healing, and nerve regeneration. In addition to its intrinsic biocompatibility, keratin interacts with specific cell receptors eliciting beneficial biochemical cues. However, during extraction from na...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.23037
更新日期:2017-10-01 00:00:00
abstract::Elastin-like polypeptide (ELP) fusions have been designed to allow large-scale, nonchromatographic purification of many soluble proteins by using the inverse transition cycling (ITC) method; however, the sensitivity of the aqueous lower critical solubility phase transition temperature (T(t)) of ELPs to the addition of...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.22137
更新日期:2013-01-01 00:00:00
abstract::The two hemoglobin structures determined by Max Perutz, the liganded R-state, which has high oxygen affinity, and the unliganded T-state with low oxygen affinity, were landmarks in molecular and structural biology (Perutz and Lehman, Nature 1968, 219, 902-909; Bolton and Perutz, Nature 1970, 28, 551-552; Perutz et al....
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.21197
更新日期:2009-12-01 00:00:00
abstract::Ultraviolet hyperchromicity experiments indicate that in DNA duplex formation, a C-T mismatch is destabilizing in the center of a duplex, but behaves as a stable base pair at the terminus of a duplex. The C-T base pair is thought to contain two hydrogen bonds, but has thermodynamic parameters (delta Ho and delta Go of...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.360310908
更新日期:1991-08-01 00:00:00
abstract::A desire to replicate the structural and functional complexity of proteins with structured, sequence-specific oligomers motivates study of the structural features of water-soluble peptoids (N-substituted glycine oligomers). Understanding the molecular-level details of peptoid self-assembly in water is essential to adv...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.23248
更新日期:2019-04-01 00:00:00
abstract::Nuclear magnetic resonance and optical experiments are combined to determine the rms amplitude of local angular motion of purines in DNA in solution. A 12 base-pair duplex DNA with the sequence d(CGCGAATTCGCG)2 is deuterated at the H8 positions of adenine and guanine by exchange with solvent at 55 degrees C. The deute...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.360340404
更新日期:1994-04-01 00:00:00
abstract::Conformational analysis of the neurohypophyseal hormones oxytocin (OT) and arginine-vasopressin (AVP) has been carried out using two different computational approaches and three force fields, namely by the Electrostatically Driven Monte Carlo (EDMC) method, with the Empirical Conformational Energy Program for Peptides...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/(sici)1097-0282(199602)38:2<157::aid-bip3>
更新日期:1996-02-01 00:00:00
abstract::The spectroscopic properties of syringomycin E, an antibiotic lipodepsinonapeptide associated with pathological states in plants, have been investigated by uv absorbance and CD spectroscopies, and by the synthesis of relevant model compounds. Initial studies [E. Vaillo, A. Ballio, P. L. Luisi, and R. M. Thomas (1990) ...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.360321006
更新日期:1992-10-01 00:00:00
abstract::Near uv CD spectra of Trp residues in proteins frequently show a complex line shape deriving from the overlap of 1La and 1Lb electronic transitions. This study presents an original empirical method of resolving these components, based on the near uv CD spectra of well-defined complexes of calmodulin domains with targe...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/(SICI)1097-0282(199806)45:7<493::AID-BIP3>
更新日期:1998-06-01 00:00:00
abstract::The hinge region links the antigen binding Fab part to the constant Fc domain in immunoglobulins. For the hinge peptide derivative [AcThr(OtBu)-Cys-Pro-Pro-Cys-Pro-Ala-ProNH2]2 the assignment of the 1H and 13C resonances was achieved by two-dimensional nmr techniques: total correlation spectroscopy (TOCSY), nuclear Ov...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.360311007
更新日期:1991-09-01 00:00:00
abstract::Study of model beta-hairpin peptides allows for better understanding of the factors involved in the formation of beta-sheet secondary structure in proteins. It is known that turn sequence, sidechain-sidechain interactions, interstrand hydrogen bonding, and beta-sheet propensity of residues are all important for beta-h...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.20840
更新日期:2008-01-01 00:00:00
abstract::Fluorescein-labeled antibodies are widely used in clinical assays and fluorescence microscopy. The fluorescent signal per labeled antibody is limited by fluorescein self-quenching, which occurs when the antibody is heavily labeled with multiple fluoresceins. We examined immunoglobulin G (IgG) when labeled with 0.7 to ...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.20098
更新日期:2004-08-15 00:00:00
abstract::Molecular structures for parallel DNA and RNA double helices with Hoogsteen pairing are proposed for the first time. The DNA helices have sugars in the C2'-endo region and the phosphodiester conformations are (trans, gauche-), and the RNA helices have sugars in the C3'-endo region and the phosphodiester conformations ...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.360341202
更新日期:1994-12-01 00:00:00
abstract::Seven water-insoluble (1 --> 3)-beta-D-glucan fractions TM8-1 to TM8-7 with weight-average molecular mass M(w) ranged from 2.22 to 77.4 x 10(4) obtained from the sclerotia of Pleurotus tuber-regium were carboxymethylated to produce the water-soluble fractions CTM8-1 to CTM8-7 with M(w) ranged from 3.87 to 87.8 x 10(4)...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.10277
更新日期:2003-02-01 00:00:00
abstract::A natural rubber was identified and characterized for the first time in the latex of the perennial Mediterranean shrub Euphorbia characias. Four different methods, i.e., acetone, acetic acid, trichloroacetic acid, and Triton® X-100, followed by successive treatments with cyclohexane/ethanol, were employed to extract t...
journal_title:Biopolymers
pub_type: 杂志文章
doi:10.1002/bip.22044
更新日期:2012-08-01 00:00:00