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Highlights: [•] Pre-eclamptic/eclamptic pregnancies influence the oxidative stress in newborn. [•] Released iron in pre-eclampsia/eclampsia may contribute to the oxidative stress. [•] Deficiency of antioxidants as result of utero-placental vascular insufficiency. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: To understand the association between markers of oxidative stress, levels of vascular endothelial growth factor (VEGF), and cell proliferation index in relation to disease progression, clinical stage, and cytologic grade in pathophysiology of prostate carcinoma. Patients and methods: Case control study comprised of 40 prostate carcinoma patients along with 40 age- and sex-matched healthy subjects as controls. Levels of 8-hydroxy-2-deoxy guanosine, protein carbonyl, and malondialdehyde along with total antioxidant status were measured to study the oxidative stress status in the study subjects. Angiogenesis was evaluated by studying the VEGF level and cell proliferation index. Results: The levels of markers of oxidative stress along with VEGF and cell proliferation index were found to be significantly higher with significantly decreased levels of antioxidant activity in the study subjects in comparison with healthy controls. The results indicate oxidative stress, angiogenesis, and cell proliferation activity increase progressively with the increase in staging and progression of disease. Conclusions: Oxidative stress parameters, angiogenesis, and cell proliferation activity point clearly that with the progression of oxidative stress there is a simultaneous progression of angiogenesis, regulation and control of endothelial cell proliferation in relation to disease progression, clinical stage, and cytologic grade in the pathophysiology of prostate carcinoma. [Copyright &y& Elsevier]

Objective: The objective of the study is to investigate the association between oxidative stress markers and enzymatic / non-enzymatic antioxidants (marker of the resistance in body to oxidative damage) in the cord blood of preterm low birth weight (LBW) neonates. Methods: Malondialdehyde (MDA), carbonyl proteins, total antioxidant capacity and Vitamin A, E and C levels in the cord blood were determined by spectrophotometry. Results: Increased lipid peroxidation, protein oxidation with decreased values of vitamin A, E, C and total antioxidant capacity were observed in the preterm LBW newborns. Observations of negative correlation between MDA and protein carbonyl with antioxidants vitamin A, E and C and total antioxidant status points towards the existence of oxidative stress in the preterm LBW newborns. Conclusions: Poor fetal growth affects the development of antioxidant defenses of preterm LBW babies, predisposing them to higher oxidative stress, which in turn may partly account for increased morbidity and mortality in these infants. The presence of an association between oxidative stress biomarkers and enzymatic /non-enzymatic antioxidants in the cord blood of preterm LBW neonates suggest that increased oxidative stress may be the result of changes in the levels of certain enzymatic and non-enzymatic antioxidants due to the cause or the effect of oxidative damage occurring at the molecular level. [ABSTRACT FROM AUTHOR]

Pd(II) catalyzed oxidation of paracetamol (PA) by sodium N-chloro p-toluenesulfonamide (chloramine-T or CAT) was studied in HClO4and NaOH solutions at 303 K. The stoichiometry and the oxidation product in both solutions were found to be the same. The determined stoichiometric ratio was 1:2 ([PA]:[CAT]) and quinone oxime was identified as the oxidized product of PA. However, the kinetics patterns in both media were different. In the acidic medium, the rate law was −d[CAT]/dt= k[CAT][PA]0.9[Pd(II)]0.8[H]−0.4and the rate law was −d[CAT]/dt= k[CAT][PA]0.9[Pd(II)] [PTS]−0.4[NaOH]−1in the alkaline medium. p-Toluenesulphonamide (PTS) is the reduced product of CAT. The kinetics of the reaction was studied as a function of temperature, ionic strength, concentration of the salt, concentration of the added reaction product, and dielectric constant of the medium to learn the mechanistic aspects of the reaction. A plausible mechanism is proposed, which is consistent with the kinetics, stoichiometry, and product of the reaction. [ABSTRACT FROM AUTHOR]

The article focuses on a study related to the evaluation of oxidative stress and antioxidant defense in patients with chronic myeloid leukemia (CML). The study mentions that CML is a myeloproliferative disorder and results from chromosomal translocation. The study informs that data were collected with serum from 40 clinically diagnosed cases of CML as well as 40 healthy controls. The study further concludes that oxidative stress may play a role in the pathogenesis of CML.

The present paper deals with the kinetics and mechanism of Ru(III)-catalyzed oxidation of paracetamol by chloramine-T (CAT) in aqueous perchloric acid medium at 303 K. The experimental result shows a first order dependence on paracetamol at its low concentrations, but tending towards zeroth order at its higher concentrations. The reactions follow a first order rate dependence with respect to oxidant [CAT] and [Ru(III)]. The reaction showed negative fractional-order dependence on the rate for [H+] and p-toluenesulphonamide. Variation in [Cl−] and ionic strength of the medium did not bring about any significant change on the rate of reaction. The decrease in the reaction rate with decrease in the dielectric constant of the medium was observed in the oxidation of paracetamol. Kinetic and equivalence studies together with product analysis, observed effect of dielectric constant of the medium on the rate of reaction and activation parameters furnished a basis for the formation of a common reaction mechanism for the Ru(III)-catalyzed oxidation of paracetamol by CAT in the acidic medium. [ABSTRACT FROM AUTHOR]

Abstract: The mechanistic study of iridium (III)-catalyzed oxidation of paracetamol has been studied by sodium N-chloro-p-toluenesulfonamide (chloramine-T) in aqueous perchloric acid medium at 308K. The reaction followed first-order kinetics with respect to [chloramine-T], [paracetamol] and [Cl−] in their lower concentrations range, tending to zero-order at their higher concentrations. First-order kinetics with respect to [Ir(III)] was observed for the oxidation of paracetamol. The rate of reaction decreased with increasing [H+] and [p-toluene sulphonamide, PTS] were observed for the oxidation of paracetamol. The variation of the ionic strength of the medium had no significant effect on the rate of the reaction. The first-order rate constant increased with decrease in the dielectric constant of the medium. The values of rate constants observed at five different temperatures were utilized to calculate the activation parameters. The reaction between chloramine-T and paracetamol in acid medium exhibits 1:2 stoichiometry. A plausible mechanism from the results of kinetic studies, reaction stoichiometry and product analysis has been proposed. [Copyright &y& Elsevier]

Objectives: To analyze the status of oxidative stress in relation to the degree of prematurity and birthweight of neonates. Materials and methods: Umbilical cord blood samples were obtained at the time of delivery. 8-Hydroxy-2-deoxy guanosine (8-OHdG) has been measured as oxidative DNA damage marker in preterm low-birthweight (LBW) newborns by competitive in vitro enzyme-linked immunosorbent assay (ELISA) along with malondialdehyde (MDA) as marker of lipid peroxidation and total antioxidant status to study the oxidative stress. Results: Significant elevation in the levels of 8-OHdG along with malondialdehyde has been noted in preterm LBW newborns. Serum 8-OHdG is found to be significantly and negatively correlated with birthweight (r = −0.834, p < 0.001) and gestational age of the newborn (r = −0.626, p < 0.001). Conclusion: These results provide evidence of increased oxidative stress in the form of DNA damage and lipid peroxidation in premature LBW newborns, which may be responsible for different complications associated with prematurity. [ABSTRACT FROM PUBLISHER]

Kinetic studies in homogenous Ru(III) catalyzed oxidation of l-leucine (Leu), by N-bromophthalimide (NBP) in the presence of perchloric acid have been made at 303 K using mercuric acetate as Br ion scavenger. The reaction follows first-order kinetics with respect to [NBP]. In the lower concentration range of Leu and Ru(III) chloride, the reaction follows first-order kinetics but tends to zero at higher concentration. A positive effect of [Cl] was observed in the oxidation of Leu. An increase in the rate of reaction with the decrease in dielectric constant of the medium was observed while negative effect was observed for [H]. The rate of oxidation is unaffected by the change in [phthalimide (NHP)]. Rate of reaction decreased with increase in ionic strength of the medium. The main oxidation products of the reactions were identified as aldehyde, ammonia and CO for the oxidation of Leu. From the effect of temperature (298-318 K) on the reaction rate, various activation parameters have been calculated and on the basis of these parameters, a suitable explanation for the reaction mechanism has been given. [ABSTRACT FROM AUTHOR]

The intracellular redox environment plays an important role in the maintenance of proper cellular homeostasis and functions. Disturbances in redox equilibrium of cells result in pro-inflammatory conditions, and these inflammatory conditions can induce carcinogenesis or increase the malignant potential of the tumor. Oxidative stress or tissue damage can trigger toll-like receptor (TLR) family of receptors that are involved in altering the innate immune system. The present study was aimed at evaluating the level of oxidative damage markers in breast diseases by measuring the 8-hydroxydeoxyguanosine (8-OHdG), protein carbonyl (PC), malondialdehyde (MDA), and total antioxidant status (TAS) alterations in relation to expression of TLR-9. A significant increase in the level of oxidative damage markers was observed in breast carcinoma patients in comparison to benign and normal controls, which was accompanied by a significant decrease in TAS and expression of TLR-9 concentrations. 8-OHdG, PC, and MDA were negatively correlated with expression of TLR-9 and TAS levels. Altered levels of biomarkers of oxidative stress and TLR-9 among the malignant, benign, and controls suggest a correlation of oxidative stress and TLR signaling in the progression of disease in breast carcinoma patients. Receiver operating characteristic analysis depicts that expression of TLR-9 is a good indicator for distinguishing cancer patients from benign and normal controls. High accuracy, specificity, and sensitivity of oxidative stress markers and expression of TLR-9 can be used as discriminatory marker/s for efficient diagnosis. [ABSTRACT FROM AUTHOR]

The mechanistic study of Ir(III) chloride catalyzed oxidation of Val has been studied by by N-bromophthalimide (NBP) in aqueous perchloric acid medium at 303 K. The reaction followed first order kinetics with respect to [NBP] and zero order kinetics with respect to [Val]. At lower concentration range of Ir(III) chloride, the reaction followed first order kinetics while tending to zero order at its higher concentration. A negative effect was observed for [H+] and [NHP] (phthalimide) whereas variation in [Hg(OAc)2] (mercuric acetate), [Cl-], ionic strength (I) and dielectric constant of the medium did not bring about any significant change on the rate of reaction. The rate constants observed at five different temperatures (298 K-318 K) were used to calculate the activation parameters. A plausible mechanism from the results of kinetic studies, reaction stoichiometry and product analysis has been proposed. [ABSTRACT FROM AUTHOR]

Kinetics of Ruthenium(III) [Ru(III)] chloride catalyzed oxidation of valine (Val) has been studied by N-bromophthalimide (NBP) in the acidic medium at 35 °C. The reaction rate follows first-order and zero-order dependence with respect to [NBP] and [Val]. First-order kinetics was observed for Ru(III) chloride at low range of concentrations and tending towards zero-order at higher concentrations. A negative effect was observed for [H+] and [phthalimide], while a positive effect was observed for [Cl−] on the reaction rate. Hg(OAc)2, ionic strength (I), and dielectric constant ( D) of the medium did not change significantly the reaction rate. The rate constants as a function of temperature (298–318 K) were used to calculate activation parameters of the oxidation of Val by NBP. A plausible mechanism was proposed to explain the results of kinetic studies, reaction stoichiometry and product analysis. [ABSTRACT FROM AUTHOR]