Hydrogen Peroxide Research Papers - Academia.edu (original) (raw)

Idiopathic pulmonary fibrosis (IPF) is thought to involve inflammatory infiltration of leukocytes, lung injury induced by reactive oxygen species (ROS), in particular superoxide anion, and fibrosis (collagen deposition). No treatment has... more

Idiopathic pulmonary fibrosis (IPF) is thought to involve inflammatory infiltration of leukocytes, lung injury induced by reactive oxygen species (ROS), in particular superoxide anion, and fibrosis (collagen deposition). No treatment has been shown to improve definitively the prognosis for IPF patients. Superoxide dismutase (SOD) catalyzes the dismutation of superoxide anion to hydrogen peroxide, which is subsequently detoxified by catalase. Lecithinized SOD (PC-SOD) has overcome clinical limitations of SOD, including low tissue affinity and low stability in plasma. In this study, we examined the effect of PC-SOD on bleomycin-induced pulmonary fibrosis. Severity of the bleomycin-induced fibrosis in mice was assessed by various methods, including determination of hydroxyproline levels in lung tissue. Intravenous administration of PC-SOD suppressed the bleomycin-induced increase in the number of leukocytes in bronchoalveolar lavage fluid. Bleomycin-induced collagen deposition and incr...

This study was designed to determine the predictive value of lipid hydroperoxide (LOOH) levels for adverse cardiovascular outcomes in patients with stable coronary artery disease (CAD). Oxidative modification of circulating lipids... more

This study was designed to determine the predictive value of lipid hydroperoxide (LOOH) levels for adverse cardiovascular outcomes in patients with stable coronary artery disease (CAD). Oxidative modification of circulating lipids contributes to inflammation and endothelial dysfunction, which are hallmark features of atherosclerosis. A serum biomarker of oxidation is LOOH, which is a primary product of fatty acid peroxidation. Serum LOOH levels were measured and correlated with clinical events over a 3-year period in 634 patients with angiographic evidence of CAD. Baseline LOOH levels in the highest quartile were associated with hazard ratios of 3.24 (95% confidence interval [CI] 1.86 to 5.65; p = 0.0001) for nonfatal vascular events (n = 149), 1.80 (95% CI 1.13 to 2.88; p = 0.014) for major vascular procedures (n = 139), and 2.23 (95% CI 1.44 to 3.44; p = 0.0003) for all vascular events and procedures. Baseline LOOH levels correlated with serum levels of soluble intercellular adhesion molecule-1 (p = 0.001) and thiobarbituric acid reactive substances (p = 0.001) as well as the mean percent change in stenosis for large segments >50% stenosed (p = 0.048). A multivariate proportional hazards model, adjusted for traditional risk factors and inflammatory markers, showed an independent effect of LOOH on nonfatal vascular events, vascular procedures, and all events or procedures. Amlodipine treatment was associated with reduced cardiovascular events and changes in LOOH levels compared with placebo. Elevated LOOH levels were predictive of nonfatal vascular events and procedures in patients with stable CAD, independent of traditional risk factors and inflammatory markers.

Resveratrol is a natural molecule with antioxidant action. Moreover, resveratrol is also considered to be a molecule with anti-inflammatory action, an effect attributed to suppression of prostaglandin (PG) biosynthesis. The aim of the... more

Resveratrol is a natural molecule with antioxidant action. Moreover, resveratrol is also considered to be a molecule with anti-inflammatory action, an effect attributed to suppression of prostaglandin (PG) biosynthesis. The aim of the present study was to investigate the effects of resveratrol, a polyphenol present in most red wines, on reactive oxygen species formation as well as on arachidonic acid (AA) release, cyclooxygenase expression, and PG synthesis in murine resident peritoneal macrophages. Results show that resveratrol exerted a strong inhibitory effect on superoxide radical (O2−) and hydrogen peroxide (H2O2) produced by macrophages stimulated by lipopolysaccharides (LPS) or phorbol esters (PMA). Resveratrol also significantly decreased [3H]AA release induced by LPS and PMA or by exposure to O2− or H2O2. Resveratrol treatment caused a significant impairment of cyclooxygenase-2 (COX-2) induction stimulated by LPS and PMA or by O2− or H2O2 exposure. These effects of resveratrol on [3H]AA release and COX-2 overexpression were correlated with a marked reduction of PG synthesis. Our results indicate that the antioxidant action of resveratrol affects AA mobilization and COX-2 induction.

Ingestion of industrial-strength hydrogen peroxide is rare. Fatal outcomes have been reported with solutions of 35%. We report a six-year-old boy who unintentionally ingested an unknown quantity of hydrogen peroxide with a concentration... more

Ingestion of industrial-strength hydrogen peroxide is rare. Fatal outcomes have been reported with solutions of 35%. We report a six-year-old boy who unintentionally ingested an unknown quantity of hydrogen peroxide with a concentration of 60%. Upon admission to our Pediatric Intensive Care Unit he was intubated and received ventilatory assistance for 48h. Upper gastrointestinal endoscopy was performed soon after admission and laparoscopy was performed 24h later. Recovery was satisfactory, and the patient was discharged on day 18 with no evidence of pathological sequelae.

The combination of UV irradiation and hydrogen peroxide (UV–H2O2) was shown to be effective in treating water spiked with 2,2′,4,4′,5,5′-hexachlorobipheny (PCB 153), reducing its concentration by as much as 98%. To test the toxicity of... more

The combination of UV irradiation and hydrogen peroxide (UV–H2O2) was shown to be effective in treating water spiked with 2,2′,4,4′,5,5′-hexachlorobipheny (PCB 153), reducing its concentration by as much as 98%. To test the toxicity of the effluent, bioassays involving three species of primary producers were performed. Results showed the effluent exerting an adverse effect on the algae Scenedesmus bijugatus and

A green and sustainable method for the oxidation of 1,3-dihydrobenzo[c] thiophenes to sulfones using metalloporphyrin complexes Two efficient methods are reported for the oxidation of 1,3-dihydrobenzo[c]thiophenes to sulfones in good to... more

A green and sustainable method for the oxidation of 1,3-dihydrobenzo[c] thiophenes to sulfones using metalloporphyrin complexes Two efficient methods are reported for the oxidation of 1,3-dihydrobenzo[c]thiophenes to sulfones in good to high yields using H 2 O 2 in the presence of catalytic amounts of porphyrin-based catalysts in ethanol or acetonitrile as solvents at room temperature. The presence of electron-donating or electron-withdrawing groups, in the benzene ring of 1,3-dihydrobenzo[c]thiophene, is well tolerated.

ABSTRACT The catalytic activity of copper-based metal organic framework compound (Cu-MOF) in the wet hydrogen peroxide catalytic oxidation (WHPCO), using p-coumaric acid as model phenolic compound, have been studied and compared with that... more

ABSTRACT The catalytic activity of copper-based metal organic framework compound (Cu-MOF) in the wet hydrogen peroxide catalytic oxidation (WHPCO), using p-coumaric acid as model phenolic compound, have been studied and compared with that of a copper-based pillared clays (Cu-PILC). Cu-MOF shows a high activity, but a structural and morphological change is observed during the reaction, even if the activity of the reused catalyst is higher in consecutive cycles with respect to that of the fresh sample.

Introduction: Residual oxygen-free radicals of bleaching agents before composite restorations can increase microleakage in enamel and dentin margins, and also various bleaching techniques are being developed using light sources. The... more

Introduction: Residual oxygen-free radicals of bleaching agents before composite restorations can increase microleakage in enamel and dentin margins, and also various bleaching techniques are being developed using light sources. The present study was conducted to compare the effect of diode laser bleaching and LED activated bleaching on the microleakage of composite restorations.
Materials & Methods: This in-vitro study was conducted on 84 extracted human premolars in three groups: In group one, class-V cavities were prepared and the teeth (n=12) were restored with composite ten days after bleaching with 35% hydrogen peroxide with no activator. In groups two and three (n=36 each), the teeth were bleached with a Diode laser activator and LED, respectively. Thereafter, each group was divided into three subgroups (n=12), cavities were prepared and restored with composite three, five, and ten days after bleaching. Digital photographs were used to assess microleakage in the enamel and dentin margins. Data were analyzed using Friedman and Wilcoxon Signed Ranks tests (p<0.05).
Results: The lowest amount of microleakage in the enamel margin pertained to the diode laser ten-day subgroup (0.17±0.38) and the diode laser ten-day subgroup in the dentin margin (0.50±1.03). Also, the highest amount of microleakage in the LED group was in the three-day subgroup of the dentin margin (2.78±0.42). Five-day subgroup of diode laser-activated bleaching had a lower amount of microleakage compared to the control group (P=0.042).
Conclusion: It may be concluded that diode laser-activated bleaching with 35% hydrogen peroxide has a better effect on reducing microleakage with an interval of five to ten days, compared to the control and LED activated bleaching group.

Previous studies suggest membrane binding is a key determinant of amyloid β (Aβ) neurotoxicity. However, it is unclear whether this interaction is receptor driven. To address this issue, a D-handed enantiomer of Aβ42 (D-Aβ42) was... more

Previous studies suggest membrane binding is a key determinant of amyloid β (Aβ) neurotoxicity. However, it is unclear whether this interaction is receptor driven. To address this issue, a D-handed enantiomer of Aβ42 (D-Aβ42) was synthesized and its biophysical and neurotoxic properties were compared to the wild-type Aβ42 (L-Aβ42). The results showed D- and L-Aβ42 are chemically equivalent with respect to copper binding, generation of reactive oxygen species and aggregation profiles. Cell binding studies show both peptides bound to cultured cortical neurons. However, only L-Aβ42 was neurotoxic and inhibited long term potentiation indicating L-Aβ42 requires a stereospecific target to mediate toxicity. We identified the lipid phosphatidylserine, as a potential target. Annexin V, which has very high affinity for externalized phosphatidylserine, significantly inhibited L-Aβ42 but not D-Aβ42 binding to the cultured cortical neurons and significantly rescued L-Aβ42 neurotoxicity. This suggests that Aβ mediated toxicity in Alzheimer disease is dependent upon Aβ binding to phosphatidylserine on neuronal cells.

Growing evidence suggests that oxidative stress is involved in the neuronal degeneration and can promote the aggregation of α-synuclein. However, the role of α-synuclein under physiological and pathological conditions remains poorly... more

Growing evidence suggests that oxidative stress is involved in the neuronal degeneration and can promote the aggregation of α-synuclein. However, the role of α-synuclein under physiological and pathological conditions remains poorly understood. In the present study, we examined the possible interaction between the α-synuclein and oxidative stress. In a dopaminergic cell line MES23.5, we have found that the 200μM H2O2

Photo-Fenton degradation of a reactive dyestuff, Reactive Black 5, was investigated in this study. The effects of UV light on Fenton Reagent process and the influence of reagents dosage, UV light intensity and initial dissolved oxygen... more

Photo-Fenton degradation of a reactive dyestuff, Reactive Black 5, was investigated in this study. The effects of UV light on Fenton Reagent process and the influence of reagents dosage, UV light intensity and initial dissolved oxygen concentration on photo-Fenton were explored. The experiments were conducted in a 3-L batch-mode reactor and were designed using Response Surface Method. The performance of