8,946 results on '"oxidants"'
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2. ELECTRON-DONOR OR ELECTRON-ACCEPTOR PROPERTIES AND CARCINOGENIC ACTIVITY OF ORGANIC MOLECULES.
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PULLMAN B and PULLMAN A
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- Carcinogens, Chemical Phenomena, Chemistry, Electrons, Hydrocarbons, Oxidants, Reducing Agents
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- 1963
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3. FURTHER EFFECTS OF TEMPERATURE AND PRESSURE ON PHOTOCHEMICAL OXIDANT PRODUCTION.
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JACUMIN WJ and RIPPERTON LA
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- Air Pollution, Chemical Phenomena, Chemistry, Light, Nitrogen, Nitrogen Dioxide, Oxidants, Oxidants, Photochemical, Ozone, Pressure, Research, Temperature
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- 1964
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4. Oxidation of Sulphur pollutants in model and real fuels using hydrodynamic cavitation
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Peter Delaney, Varaha P. Sarvothaman, Sanjay Nagarajan, David Rooney, Peter K.J. Robertson, and Vivek V. Ranade
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Oxidative desulphurization ,Hydrodynamic cavitation ,Fuels ,Catalysts ,Oxidants ,Chemistry ,QD1-999 ,Acoustics. Sound ,QC221-246 - Abstract
Hydrodynamic Cavitation (HC) offers an attractive platform for intensifying oxidative desulphurization of fuels. In the first part of this work, we present new results on oxidising single ring thiophene in a model fuel over the extended range of volume fraction of organic phase from 2.5 to 80 v/v %. We also present influence of type and scale of HC device on performance of oxidative desulphurization. Further experiments revealed that oxidising radicals generated in-situ by HC alone were not able to oxidise dual ring thiophenes. External catalyst (formic acid) and oxidising agents (hydrogen peroxide, H2O2) were therefore used with HC. Based on our prior work with acoustic cavitation (AC), the volumetric ratios for H2O2 and formic acid were identified as 0.95 v/v % and 6.25 v/v % respectively. The data of oxidation of dual ring thiophenes with n-dodecane and n-hexane as model fuels and typical transport fuels (diesel, kerosene, and petrol) using these oxidant and catalyst is presented. The observed performance with HC was compared with results obtained from a stirred tank and AC set-up. The presented data indicates that HC is able to intensify oxidation of sulphur species. The presented results provide a sound basis for further developments on HC based oxidative desulphurization processes.
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- 2023
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5. Performance comparison of photocatalysts for degradation of organic pollutants using experimental studies supported with DFT and fundamental characterization
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Nandana Chakinala, Prabhat Ranjan, Anand G. Chakinala, and Parag R. Gogate
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Photocatalysis ,Bi-metallic catalysts ,PNP degradation ,Oxidants ,DFT computations ,Chemistry ,QD1-999 - Abstract
The effect of different metal supported TiO2 catalysts on the photocatalytic degradation of p-Nitrophenol (PNP) was investigated experimentally and supported by Density Functional Theory (DFT) approach. Process optimization studies were carried out using the best performing catalyst and the effect of different electron acceptors was also investigated. Degradation was strongly influenced by operating parameters and oxidants with efficacy as H2O2 > K2S2O8 > air. DFT simulations confirmed higher electrostatic potential in presence of hydroxyl radicals explaining the higher degradation. Overall, this work clearly establishes the effectiveness of electron acceptors in maximizing PNP degradation and explains the interaction of organic pollutants with different radicals.
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- 2023
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6. Findings from Tsinghua University Has Provided New Data on Chemicals and Chemistry [Assessing Excimer Far-uvc (222 Nm) Irradiation for Advanced Oxidation Processes: Oxidants Photochemistry and Micropollutants Degradation].
- Abstract
A report from Tsinghua University in Shenzhen, People's Republic of China, discusses the use of KrCl excimer lamp (UV222) for advanced oxidation processes (UV-AOPs) in chemical and chemistry research. The study found that UV222 outperformed UV254 in activating oxidants, with PDS being the optimum oxidant for degrading micropollutants under UV222 irradiation. The research aims to fill gaps in photochemistry knowledge and improve engineering practices of UV222-AOPs. This study was funded by various organizations, including the National Natural Science Foundation of China and the Shenzhen Science and Technology Program. [Extracted from the article]
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- 2024
7. Oxidants Emergence under Dual-Frequency Sonication within Single Acoustic Bubble: Effects of Frequency Combinations
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Kaouther Kerboua and Oualid Hamdaoui
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dual-frequency ,oxidants ,sonochemical activity ,acoustic cavitation bubble ,kinetics ,Chemical engineering ,TP155-156 ,Chemistry ,QD1-999 - Abstract
The sonochemical activity of an oxygen bubble formed in an aqueous medium and oscillating under a dual-frequency excitation is studied in this paper. Several couples of frequencies are formed amongst 35, 140, 300, and 515 kHz, with a maximum acoustic amplitude of 1.5 atm. The molar yields of the emerging oxidants are analyzed in accordance with the combined frequencies and compared to the cases of mono-frequency excitations of similar maximum amplitude, i.e., 1.5 atm. Qualitatively, passing from a mono to a dual-frequency excitation demonstrated to be with no effect on the predominant species which remain, and. However, the results exhibited a very selective quantitative evolution depending on the combined frequencies. Some couples proved to induce a negative effect and reduce the production at the single bubble level, particularly with basic frequencies of 140 and 300 kHz, while some others demonstrated a noticeable enhancement such as the couples (35, 140 kHz) and (515, 35 kHz), as compared to mono-frequency fields.
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- 2021
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8. Recent Advances on Copper-Catalyzed C–C Bond Formation via C–H Functionalization.
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Almasalma, Ahmad A. and Mejía, Esteban
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COINAGE , *COPPER catalysts , *CLASS B metals , *PRECIOUS metals , *CHEMISTRY , *NATURE - Abstract
Reactions that form C–C bonds are at the heart of many important transformations, both in industry and in academia. From the myriad of catalytic approaches to achieve such transformations, those relying on C–H functionalization are gaining increasing interest due to their inherent sustainable nature. In this short review, we showcase the most recent advances in the field of C–C bond formation via C–H functionalization, but focusing only on those methodologies relying on copper catalysts. This coinage metal has gained increased popularity in recent years, not only because it is cheaper and more abundant than precious metals, but also thanks to its rich and versatile chemistry. 1 Introduction 2 Cross-Dehydrogenative Coupling under Thermal Conditions 2.1 C(sp3)–C(sp3) Bond Formation 2.2 C(sp3)–C(sp2) Bond Formation 2.3 C(sp2)–C(sp2) Bond Formation 2.4 C(sp3)–C(sp) Bond Formation 3 Cross-Dehydrogenative Coupling under Photochemical Conditions 3.1 C(sp3)–C(sp3) Bond Formation 3.2 C(sp3)–C(sp2) and C(sp3)–C(sp) Bond Formation 4 Conclusion and Perspective [ABSTRACT FROM AUTHOR]
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- 2020
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9. Patch testing with ammonium persulfate: The North American Contact Dermatitis Group Experience, 2015-2018
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Donald V. Belsito, Joel G. DeKoven, Jonathan I. Silverberg, Marie-Claude Houle, Howard I. Maibach, Kathryn A. Zug, Margo J. Reeder, Cory A. Dunnick, Erin M. Warshaw, James S. Taylor, Vincent A. DeLeo, Amber Reck Atwater, Melanie D. Pratt, Anthony F. Fransway, Jenna L. Ruggiero, Joseph F. Fowler, and Denis Sasseville
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Male ,medicine.medical_specialty ,Petrolatum ,Eczema ,Hair Preparations ,Dermatology ,Patch testing ,Sodium persulfate ,chemistry.chemical_compound ,medicine ,Retrospective analysis ,Humans ,Allergic contact dermatitis ,Retrospective Studies ,business.industry ,Water ,Patch test ,Allergens ,Patch Tests ,Oxidants ,medicine.disease ,Dermatitis, Occupational ,chemistry ,Ammonium Sulfate ,Dermatitis, Allergic Contact ,North America ,Hand dermatitis ,Female ,Ammonium persulfate ,business ,Contact dermatitis - Abstract
Ammonium persulfate (APS), an oxidizing agent used in hair products, manufacturing, and pool/spa water, can cause skin reactions, including allergic contact dermatitis.To characterize positive patch test reactions to APS (2.5% petrolatum).Retrospective analysis of patients tested to the North American Contact Dermatitis Group screening series from 2015 to 2018.Of 10,526 patients, 193 (1.8%) had positive patch test reactions to APS. Compared with APS-negative patients, APS-positive patients were significantly more likely to be male (43.2% vs 28.0%; P .0001); have primary hand dermatitis (30.2% vs 22.0%; P = .0064), scattered generalized dermatitis (25.5% vs 17.9%; P = .0064), or trunk dermatitis (8.9% vs 4.9%; P = .0123); and have dermatitis that is occupationally related (22.2% vs 10.9%; P .0001). More than half of the APS-positive reactions were currently relevant (57.0%); 19 (9.8%) were related to occupation, especially hairdressers (68.4%). Swimming pools/spas (23.3%) and hair care products (19.2%) were the most common sources of APS.Immediate reactions and follow-up testing were not captured.The proportion of patients positive to APS was 1.8%. APS positivity was significantly associated with male sex and hand dermatitis. Swimming pool/spa chemicals were important sources of APS exposure.
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- 2022
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10. The role of metal oxides on oxidant decay and disinfection byproduct formation in drinking waters: Relevance to distribution systems
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Chao Liu
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Environmental Engineering ,Halogenation ,0208 environmental biotechnology ,Inorganic chemistry ,Oxide ,chemistry.chemical_element ,Disproportionation ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,Water Purification ,chemistry.chemical_compound ,Bromide ,Hypobromous acid ,polycyclic compounds ,Chlorine ,Environmental Chemistry ,0105 earth and related environmental sciences ,General Environmental Science ,Chlorine dioxide ,Bromine ,Drinking Water ,Chlorate ,Oxides ,General Medicine ,Oxidants ,020801 environmental engineering ,Disinfection ,chemistry ,Water Pollutants, Chemical ,Disinfectants - Abstract
Maintaining a residual disinfectant/oxidant (e.g., chlorine and chlorine dioxide), is a generally used strategy to control microbial contaminants and bacterial regrowth in distribution systems. Secondarily oxidant, such as hypobromous acid (HOBr), can be formed during chlorination of bromide-containing waters. The decay of oxidants and formation of disinfection byproducts (DBPs) due to the interaction between oxidants and selected metal oxides were studied. Selected metal oxides generally enhanced the decay of these halogen-containing oxidants via three pathways: (1) catalytic disproportionation to yield an oxidized form of halogen (i.e., halate) and reduced form (halide for chlorine and bromine or chlorite for chlorine dioxide), (2) oxygen formation, and (3) oxidation of a metal in a reduced form (e.g., cuprous oxide) to a higher oxidation state. Cupric oxide (CuO) and nickel oxide (NiO) showed significantly strong abilities for the first pathway, and oxygen formation was a side reaction. Cuprous oxide can react with oxidants via the third pathway, while goethite was not involved in these reactions. The ability of CuO on catalytic disproportionation of HOBr remained stable up to four cycles. In chlorination process, bromate formation tends to be important (exceeding 10 µg/L) when initial bromide concentration is above 400 µg/L in the presence of dissolved organic matter. Increasing initial bromide concentrations increased the formation of DBPs and calculated cytotoxicity, and the maximum was observed at pH 8.6 during chlorination process. Therefore, the possible disinfectant loss and DBP formation should be carefully considered in drinking water distribution systems.
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- 2021
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11. Heme Oxygenase 1 in Vertebrates: Friend and Foe
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Leonardo Holanda Travassos Correa and Rafael Cardoso Maciel Costa Silva
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chemistry.chemical_classification ,Programmed cell death ,Antioxidant ,Chemistry ,DNA repair ,Mechanism (biology) ,medicine.medical_treatment ,Biophysics ,Cell Biology ,General Medicine ,Oxidants ,Biochemistry ,Cell biology ,Heme oxygenase ,Enzyme ,medicine.anatomical_structure ,Vertebrates ,Sense (molecular biology) ,medicine ,Animals ,Nucleus ,Heme Oxygenase-1 - Abstract
HO-1 is the inducible form of the enzyme heme-oxygenase. HO-1 catalyzes heme breakdown, reducing the levels of this important oxidant molecule and generating antioxidant, anti-inflammatory, and anti-apoptotic byproducts. Thus, HO-1 has been described as an important stress response mechanism during both physiologic and pathological processes. Interestingly, some findings are demonstrating that uncontrolled levels of HO-1 byproducts can be associated with cell death and tissue destruction as well. Furthermore, HO-1 can be located in the nucleus, influencing gene transcription, cellular proliferation, and DNA repair. Here, we will discuss several studies that approach HO-1 effects as a protective or detrimental mechanism in different pathological conditions. In this sense, as the major organs of vertebrates will deal specifically with distinct types of stresses, we discuss the HO-1 role in each of them, exposing the contradictions associated with HO-1 expression after different insults and circumstances.
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- 2021
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12. Mitochondria-Mediated Moderation of Apoptosis by EGCG in Cytotoxic Neuronal Cells Induced by Lead (Pb) and Amyloid Peptides
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Neelima Ayyalasomayajula, Chellu S. Chetty, Suresh Challa, Lakshmi Jaya Madhuri Bandaru, and Prasanna Kumar Dixit
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Programmed cell death ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,Apoptosis ,Pharmacology ,Mitochondrion ,medicine.disease_cause ,Biochemistry ,Antioxidants ,Catechin ,Inorganic Chemistry ,Neuroblastoma ,medicine ,Humans ,MTT assay ,Viability assay ,biology ,Chemistry ,Cytochrome c ,Biochemistry (medical) ,Neurotoxicity ,Cytochromes c ,General Medicine ,Oxidants ,medicine.disease ,Mitochondria ,Oxidative Stress ,Lead ,biology.protein ,Peptides ,Oxidative stress - Abstract
The developmental, epigenetic, and epidemiological studies on lead (Pb) toxicity have reported a strong connection between lead exposure and the progression of Alzheimer’s disease (AD). The amyloid peptides were the main triggering elements, in the generation of extracellular plaques through which multiple cellular signaling events such as apoptosis and primarily oxidant-antioxidant balancing system will be affected, which leads to neuronal cell death. Our previous studies indicated that epigallocatechin gallate (EGCG), abundantly present in green tea, was found to be effective in alleviating the metal-induced neurotoxicity at the cellular level in terms of cell viability and apoptosis The aim of this study was to explore the protective mechanism of EGCG on the markers of oxidant-antioxidant system and mitochondria, which are involved in metal-induced neuronal cell death. Initially, the IC50 values for lead(Pb-5 µM), amyloid peptides (AP(1–40)-60 µM; AP(1–40)-8 µM), and EC50 value for EGCG(50 µM) were determined by both time- (12 h, 24 h, 48 h) and concentration-dependent manner and analyzed by MTT assay. The experimental groups were designed initially by treating with Pb and APs individually and in different combinations along with the presence of EGCG and are compared to the Pb and AP treated group without EGCG exposure. The cell lysates were used for analyzing oxidative stress markers by standardized laboratory protocol and the expression of mitochondrial markers such as VDAC and cytochrome C which were analyzed by both western blot and real-time PCR. Our results indicate that the EGCG-treated group has shown a significant increase in antioxidant marker expression levels (GSH, SOD, catalase, vitamin C) and a decrease in oxidative stress marker (NOS, MDA) levels when compared to the group without EGCG treatment (p
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- 2021
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13. The protective effect of boric acid on cholestatic rat liver ischemia reperfusion injury
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Arif Aslaner, Tuğrul Çakır, Serkan Güler, Şenay Yildirim, and Hamit Yasar Ellidag
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medicine.medical_specialty ,Ischemia ,liver ,Gastroenterology ,Article ,Antioxidants ,chemistry.chemical_compound ,Cholestasis ,Internal medicine ,Lactate dehydrogenase ,ischemia reperfusion ,medicine ,Animals ,Serum Albumin ,business.industry ,Albumin ,Membrane Proteins ,General Medicine ,Boric acid ,Oxidants ,medicine.disease ,Rats ,chemistry ,Biliary tract ,Reperfusion Injury ,Alkaline phosphatase ,Female ,cholestasis ,Carrier Proteins ,Ligation ,business ,Reperfusion injury ,Biomarkers - Abstract
Background/aim To evaluate the potential protective effects of Boric Acid (BA) in experimental cholestatic liver ischemia reperfusion (IR) injury model. Materials and methods The study included 24 female rats which were divided into 3 groups each containing 8 rats. The control group (Group 1) only received laparotomy. In the IR group (Group 2) biliary tract ligation was applied and 1 week later 45 minutes ischemia and 1 hour reperfusion with relaparotomy without any treatment was implemented. In the treatment BA+IR group (Group 3). 1 week after the biliary ligation intraperitoneal administration of 200 mg/kg BA was given 10 minutes before the ischemia for 45 minutes and reperfusion for 1 hour with relaparotomy. Liver tissue and blood samples were taken for histopathological and biochemical examination. Ischemia modified albumin (IMA), SCUBE1, total antioxidant status (TAS) and total oxidant status (TOS) levels were also examined. Results Compared to control, groups IR and BA+IR had higher serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), total and direct bilirubin levels. Albumin value was high in the control group and low in the other groups. In terms of IMA levels there was no significant difference between groups (p>0.05). When SCUBE-1 levels were examined groups IR and BA+IR were significantly higher than the group 1. TAS was highest in the group BA+IR whereas TOS was highest in the group IR and lower in the group BA+IR. In histopathological analysis, loss of intercellular border loss in hepatocytes, diffuse nuclear pycnosis and mild to moderate neutrophilic cell infiltration were observed in the IR group. Statisticaly significant dissociation, hemorrhage and severe neutrophilic cell infiltration were seen in hepatocytes of rats with IR (p Conclusion BA has promising results in the treatment of experimental IR injury of the cholestatic liver because of its antioxidant effects. It may be used in clinical practice after more extensive studies about the effects of BA on IR injury of the cholestatic liver.
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- 2021
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14. Modification of gingival proteoglycans by reactive oxygen species: potential mechanism of proteoglycan degradation during periodontal diseases
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Ryan Moseley and Rachel J. Waddington
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chemistry.chemical_classification ,Alanine ,Reactive oxygen species ,Sheep ,biology ,Hydrogen Peroxide ,General Medicine ,Oxidants ,medicine.disease_cause ,Biochemistry ,Amino acid ,Serine ,Glycosaminoglycan ,Extracellular matrix ,Proteoglycan ,chemistry ,biology.protein ,medicine ,Animals ,Proteoglycans ,Reactive Oxygen Species ,Periodontal Diseases ,Oxidative stress ,Glycosaminoglycans - Abstract
Reactive oxygen species (ROS) overproduction and oxidative stress are increasingly being implicated in the extracellular matrix (ECM) degradation associated with chronic inflammatory conditions, such as periodontal diseases. The present study investigated the effects of ROS exposure on the proteoglycans of gingival tissues, utilizing an in vitro model system comprised of supra-physiological oxidant concentrations, to ascertain whether gingival proteoglycan modification and degradation by ROS contributed to the underlying mechanisms of ECM destruction during active gingivitis. Proteoglycans were purified from ovine gingival tissues and exposed to increasing H2O2 concentrations or a hydroxyl radical (·OH) flux for 1 h or 24 h, and ROS effects on proteoglycan core proteins and sulfated glycosaminoglycan (GAG) chains were assessed. ROS were capable of degrading gingival proteoglycans, with ·OH species inducing greater degradative effects than H2O2 alone. Degradative effects were particularly manifested as amino acid modification, core protein cleavage, and GAG chain depolymerization. Proteoglycan core proteins were more susceptible to degradation than GAG chains with H2O2 alone, although core proteins and GAG chains were both extensively degraded by ·OH species. Proteoglycan exposure to ·OH species for 24 h induced significant core protein amino acid modification, with decreases in glutamate, proline, isoleucine, and leucine; and concomitant increases in serine, glycine, and alanine residues. As clinical reports have previously highlighted proteoglycan core protein degradation during chronic gingivitis, whereas their sulfated GAG chains remain relatively intact, these findings potentially provide further evidence to implicate ROS in the pathogenesis of active gingivitis, complementing the enzymic mechanisms of periodontal tissue destruction already established.
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- 2021
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15. Understanding Cellular Redox Homeostasis: A Challenge for Precision Medicine
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Verena Tretter, Beatrix Hochreiter, Marie Louise Zach, Katharina Krenn, and Klaus Ulrich Klein
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redox homeostasis ,oxidants ,QH301-705.5 ,precision medicine ,Organic Chemistry ,General Medicine ,Review ,Catalysis ,Computer Science Applications ,Circadian Rhythm ,Inorganic Chemistry ,Oxidative Stress ,Chemistry ,antioxidants ,Animals ,Homeostasis ,Humans ,Physical and Theoretical Chemistry ,Biology (General) ,Molecular Biology ,Oxidation-Reduction ,QD1-999 ,Spectroscopy ,Signal Transduction - Abstract
Living organisms use a large repertoire of anabolic and catabolic reactions to maintain their physiological body functions, many of which include oxidation and reduction of substrates. The scientific field of redox biology tries to understand how redox homeostasis is regulated and maintained and which mechanisms are derailed in diverse pathological developments of diseases, where oxidative or reductive stress is an issue. The term “oxidative stress” is defined as an imbalance between the generation of oxidants and the local antioxidative defense. Key mediators of oxidative stress are reactive species derived from oxygen, nitrogen, and sulfur that are signal factors at physiological concentrations but can damage cellular macromolecules when they accumulate. However, therapeutical targeting of oxidative stress in disease has proven more difficult than previously expected. Major reasons for this are the very delicate cellular redox systems that differ in the subcellular compartments with regard to their concentrations and depending on the physiological or pathological status of cells and organelles (i.e., circadian rhythm, cell cycle, metabolic need, disease stadium). As reactive species are used as signaling molecules, non-targeted broad-spectrum antioxidants in many cases will fail their therapeutic aim. Precision medicine is called to remedy the situation.
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- 2022
16. The relationship between thiol-disulfide balance and idiopathic sudden sensorineural hearing loss
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Nazim Bozan, Koray Avcı, Mehmet Aslan, Yaser Said Çetin, and Ozcan Erel
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medicine.medical_specialty ,Antioxidant ,Hearing Loss, Sensorineural ,medicine.medical_treatment ,medicine.disease_cause ,Antioxidants ,Arylesterase ,Internal medicine ,homeostasis ,medicine ,Humans ,Disulfides ,Sulfhydryl Compounds ,Total antioxidant ,status ,Peroxidase ,hearing loss ,chemistry.chemical_classification ,biology ,Aryldialkylphosphatase ,Chemistry ,Paraoxonase ,Thiol/disulphide ,Ceruloplasmin ,Sudden sensorineural ,Hearing Loss, Sudden ,Oxidants ,Endocrinology ,Total oxidant status ,Otorhinolaryngology ,Oxidative stress ,Myeloperoxidase ,biology.protein ,Thiol ,Biomarkers ,Homeostasis - Abstract
Introduction Impaired cochlear perfusion is a major etiological factor in idiopathic sudden sensorineural hearing loss. Oxidative stress has been shown to be a risk factor for oxidative damage. Objectives We investigated the role of oxidative stress in idiopathic sudden sensorineural hearing loss by comparing serum levels of oxidant and antioxidant molecules including thiol/disulfide homeostasis paraoxonase, stimulated thiol/disulfide homeostasis paraoxonase, arylesterase, ceruloplasmin and myeloperoxidase in patients who did and did not recover after treatment. Methods The amount of dynamic disulfide was calculated by determining half of the difference between the total thiols and native thiols. After the determination of native, total thiol, and disulfide amounts, the disulfide/total thiol percent ratio, native thiol/total thiol ratio and disulfide/native thiol percent ratio were calculated and then compared between the two groups. Additionally, clinical relationship between audiological recovery and native thiol, disulfide, disulfide/native thiol percent ratio, and disulfide/total thiol percent ratio levels was investigated. Blood samples were also analyzed for the assessment of thiol/disulfide homeostasis paraoxonase, stimulated thiol/disulfide homeostasis paraoxonase, arylesterase, ceruloplasmin, and myeloperoxidase levels. Results A significant difference was found between the two groups with regard to total oxidant status disulfide, disulfide/native thiol percent ratio, disulfide/total thiol percent ratio, and native thiol/total thiol ratio levels (p = 0.001, p = 0.001, p = 0.001, p = 0.003, p = 0.001, p = 0.002, respectively). However, no significant difference was found between the two groups with regard to thiol/disulfide homeostasis paraoxonase, stimulated thiol/disulfide homeostasis paraoxonase, ceruloplasmin, and myeloperoxidase levels (p > 0.05 for all). Conclusion The results supported the common hypothesis that vascular pathologies are the primary cause of idiopathic sudden sensorineural hearing loss and that other etiological factors ultimately result in vascular pathologies. The oxidant-antioxidant and thiol-disulfide balances were impaired in the idiopathic sudden sensorineural hearing loss group.
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- 2022
17. Environmental and biological controls on seasonal patterns of isoprene above a rain forest in central Amazonia.
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Wei, Dandan, Fuentes, Jose D., Gerken, Tobias, Chamecki, Marcelo, Trowbridge, Amy M., Stoy, Paul C., Katul, Gabriel G., Fisch, Gilberto, Acevedo, Otávio, Manzi, Antonio, von Randow, Celso, and dos Santos, Rosa Maria Nascimento
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ISOPRENE , *RAIN forests , *SEASONAL physiological variations , *ATMOSPHERIC boundary layer , *HYDROXYL group , *PLANTS - Abstract
The Amazon rain forest is a major global isoprene source, but little is known about its seasonal ambient concentration patterns. To investigate the environmental and phenological controls over isoprene seasonality, we measured isoprene mixing ratios, concurrent meteorological data, and leaf area indices from April 2014 to January 2015 above a rain forest in the central Amazon, Brazil. Daytime median isoprene mixing ratios varied throughout the year by a factor of two. The isoprene seasonal pattern was not solely driven by sunlight and temperature. Leaf age and quantity also contributed to the seasonal variations of isoprene concentrations, suggesting leaf phenology was a crucial variable needed to correctly estimate isoprene emissions. A zero-dimensional model incorporating the estimated emissions, atmospheric boundary layer dynamics, and air chemistry was used to assess the contributions of each process on the variability of isoprene. Surface deposition was an important sink mechanism and accounted for 78% of the nighttime loss of isoprene. Also, chemical reactions destroyed isoprene and during 6:00 to 18:00 h local time 56, 77, 69, and 69% of the emitted isoprene was chemically consumed in June, September, December, and January, respectively. Entrainment fluxes from the residual layer contributed 34% to the early-morning above-canopy isoprene mixing ratios. Sensitivity analysis showed that hydroxyl radical (HO) recycling and segregation of isoprene–HO played relatively lesser roles (up to 16%) in regulating ambient isoprene levels. Nitric oxide (NO) levels dominated isoprene chemical reaction pathways associated with consumption and production of HO under low-NO and high volatile organic compound (VOC) conditions. While surface deposition and oxidative processes altered isoprene levels, the relative importance of these factors varied seasonally with leaf phenology playing a more important role. [ABSTRACT FROM AUTHOR]
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- 2018
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18. Protective effect of dapagliflozin against cyclosporine A-induced nephrotoxicity
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Volkan Izol, Nebil Akdogan, Emine Kilic Bagir, Bülent Kaya, Ibrahim Atilla Aridogan, Halil Mahir Kaplan, and Mutlu Deger
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medicine.medical_specialty ,Health, Toxicology and Mutagenesis ,Inflammation ,Kidney ,Toxicology ,medicine.disease_cause ,Antioxidants ,Nephrotoxicity ,Mice ,chemistry.chemical_compound ,Malondialdehyde ,Internal medicine ,Animals ,Medicine ,Dapagliflozin ,bcl-2-Associated X Protein ,Peroxidase ,Pharmacology ,Chemical Health and Safety ,biology ,Caspase 3 ,business.industry ,Public Health, Environmental and Occupational Health ,General Medicine ,Oxidants ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Apoptosis ,Myeloperoxidase ,Cyclosporine ,biology.protein ,Kidney Diseases ,medicine.symptom ,business ,Immunosuppressive Agents ,Oxidative stress - Abstract
This study aimed to reveal the possible protective effect of dapagliflozin (DAPA) against acute kidney damage due to cyclosporine A (CsA). Thirty-two mice with an eight-week-old Balb\c albino strain were divided into four groups: control group, CsA group, DAPA group, and CsA + DAPA group. On day 9 of treatment, the animals were decapitated, and bilateral nephrectomy was performed. Oxidative stress and apoptosis were evaluated with caspase-3 activity, total oxidant status (TOS), total antioxidant status (TAS), malondialdehyde (MDA), myeloperoxidase (MPO), B-cell lymphoma-2 (Bcl-2), and Bcl-2-associated X protein (Bax) in the right kidney resection material. The left kidney resection material was evaluated histopathologically. CsA increased caspase-3 activity, Bax, TOS, MDA, TAS, and MPO levels, and the administration of DAPA with CsA significantly reduced this increase in levels (p < 0.001, p < 0.001, p < 0.001, p < 0.001, p < 0.001, and p < 0.001, respectively). CsA decreased Bcl-2 levels, and administration of CsA + DAPA significantly increased Bcl-2 levels compared with only CsA administration (p < 0.001). Additionally, administration of DAPA significantly reduced the histopathological findings (parenchymal inflammation, hyaline cast formation, vacuolization, and lysis of renal tubular cells) caused by CsA. DAPA reduces oxidative stress, apoptosis, and histopathological damage caused by CsA in renal tissue.
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- 2021
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19. Oxidant Stress and Acetaminophen Hepatotoxicity: Mechanism-Based Drug Development
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Hartmut Jaeschke and Anup Ramachandran
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Physiology ,Clinical Biochemistry ,Mechanism based ,Mitochondrion ,Pharmacology ,Biochemistry ,Mice ,chemistry.chemical_compound ,Drug Development ,Animals ,Humans ,Medicine ,Molecular Biology ,Acetaminophen ,General Environmental Science ,business.industry ,digestive, oral, and skin physiology ,Cell Biology ,Forum Review Articles ,Oxidants ,Mice, Inbred C57BL ,Oxidative Stress ,Liver ,chemistry ,Drug development ,General Earth and Planetary Sciences ,Chemical and Drug Induced Liver Injury ,business ,Peroxynitrite ,medicine.drug - Abstract
Significance: Acetaminophen (APAP) is one of the quantitively most consumed drugs worldwide. Although safe at therapeutic doses, intentional or unintentional overdosing occurs frequently causing severe liver injury and even liver failure. In the United States, 50% of all acute liver failure cases are caused by APAP overdose. However, only one antidote with a limited therapeutic window, N-acetylcysteine, is clinically approved. Thus, more effective therapeutic interventions are urgently needed. Recent Advances: Although APAP hepatotoxicity has been extensively studied for almost 50 years, particular progress has been made recently in two areas. First, there is now a detailed understanding of involvement of oxidative and nitrosative stress in the pathophysiology, with identification of the reactive species involved, their initial generation in mitochondria, amplification through the c-Jun N-terminal kinase pathway, and the mechanisms of cell death. Second, it was demonstrated in human hepatocytes and through biomarkers in vivo that the mechanisms of liver injury in animals accurately reflect the human pathophysiology, which allows the translation of therapeutic targets identified in animals to patients. Critical Issues: For progress, solid understanding of the pathophysiology of APAP hepatotoxicity and of a drug's targets is needed to identify promising new therapeutic intervention strategies and drugs, which may be applied to humans. Future Directions: In addition to further refine the mechanistic understanding of APAP hepatotoxicity and identify additional drugs with complementary mechanisms of action to prevent cell death, more insight into the mechanisms of regeneration and developing of drugs, which promote recovery, remains a future challenge. Antioxid. Redox Signal. 35, 718–733.
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- 2021
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20. Structure activity evaluation and computational analysis identify potent, novel 3-benzylidene chroman-4-one analogs with anti-fungal, anti-oxidant, and anti-cancer activities
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Mohamad Y. Alshahrani, Suresh Radhakrishnan, Prasanna Rajagopalan, Irfan Ahmad, Hossam Kamli, Hassan Otifi, and Gaffar Sarwar Zaman
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Antioxidant ,medicine.medical_treatment ,Pharmaceutical Science ,Estrogen receptor ,Antineoplastic Agents ,Breast Neoplasms ,Aspergillus flavus ,Antioxidants ,Structure-Activity Relationship ,Cell Line, Tumor ,Drug Discovery ,medicine ,Humans ,Structure–activity relationship ,Cell Proliferation ,Pharmacology ,Molecular Structure ,biology ,Chemistry ,Organic Chemistry ,Aspergillus niger ,Oxidants ,biology.organism_classification ,In vitro ,Enzyme binding ,Biochemistry ,Docking (molecular) ,Female ,Drug Screening Assays, Antitumor ,Proto-Oncogene Proteins c-akt - Abstract
Significance 3-benzylidene chroman-4-ones share close homology with naturally occurring bioactive compounds. Objectives This study evaluated the antifungal, antioxidant and anticancer activities of novel 3-benzylidene chromanone analogues with respect to their structure-activity relationships. Methods Compounds 45e-64e were synthesized inhouse. Aspergillus niger (MTCC 1344) Aspergillus flavus and Botrytis cinareae were the fungal strains tested. Computational docking analysis were carried out for Vanin-1, estrogen receptor and Akt proteins using Auto-dock vina. Free radical scavenging, total antioxidant capacity was analyzed using spectrophotometric methods. MCF-7(breast cancer) cell line was used for anticancer assays. Flow cytometry was used to detect cell cycle and apoptosis. Results Out of the twenty compounds screened, compounds 47e,50e,52e,57e and 61e that possessed either methoxy and ethoxy/methyl/isopropyl group exhibited very good activity against all fungi. Compounds possessing methoxy group alone showed moderate activity and compounds devoid of methoxy, and ethoxy groups did not show any activity. When computationally analyzed against target proteins for antioxidant properties, the compounds exhibited excellent binging efficacy to Vanin-1 and estrogen receptors. These predictions were translated in the in vitro free-radical scavenging and antioxidant assays. The compounds exhibited anti-proliferative efficacy in breast cancer cell line, increased the sub-G0/G1 cell cycle populations and total apoptosis in MCF-7 cells. Additionally, the compounds also depicted excelling binging energy when computationally analyzed for Akt enzyme binding. Conclusion In summary, our study identified potential analogues of 3-benzylidene chroman-4-one molecules with excellent anti-fungal, anti-oxidant and anticancer activities which demands further research for drug developments.
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- 2021
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21. Comparison of various chemical compounds for the removal of SO2 and NOx with wet scrubbing for marine diesel engines
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Chun-Yang Yin, Terence Chin, and Ivan C. K. Tam
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inorganic chemicals ,NaClO2 ,Nitrogen ,Health, Toxicology and Mutagenesis ,Inorganic chemistry ,Hypochlorite ,chemistry.chemical_element ,SO2 ,NO ,chemistry.chemical_compound ,Wet scrubbing ,Oxidizing agent ,Chlorine ,Environmental Chemistry ,KMnO4 ,NOx ,Wet scrubber ,Aqueous two-phase system ,General Medicine ,Hydrogen Peroxide ,NaClO ,Oxidants ,Pollution ,Hypochlorous Acid ,chemistry ,Absorption (chemistry) ,Oxidation-Reduction ,Data scrubbing ,Marine emissions ,Research Article - Abstract
Seawater, NaOH, NaClO, NaClO2, H2O2 and KMnO4 were used as scrubbing liquids to react with SOx and NOx separately in a customized wet scrubber. The absorption of SO2 in the aqueous phase was influenced by three factors: pH, ionic concentration and oxidation potential. For NOx removal, the effectiveness of various chemical compounds can be ranked from least to most effective as follows: Seawater, NaOH, H2O2 4 2. This effectiveness was influenced by the chemical compound’s ability to oxidize NO to NO2, absorb the NO2 that was formed and retaining the nitrogen in the aqueous phase. High oxidation potential promoted the oxidation of NO to NO2 but hindered the absorption of NO2. NaClO2 was superior compared to NaClO in all three categories of oxidizing, absorption and retention. NaClO could not retain a significant amount of NO2 which it absorbed in the aqueous phase. The pH around 8 provided a good balance between oxidation versus absorption/retention and reactant utilization for the chlorine-based oxidants. KMnO4 had the lowest reactant consumption rate; only half a mole was consumed for every mole of NO removed, compared to around 2–3 moles of chlorite or 3–5 moles of hypochlorite.
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- 2021
22. Copper-Catalyzed Cross-Coupling of Benzylic C–H Bonds and Azoles with Controlled N-Site Selectivity
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Shannon S. Stahl, Si-Jie Chen, Shane W. Krska, and Dung L. Golden
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Azoles ,Sulfonamides ,Molecular Structure ,Drug discovery ,Chemistry ,Site selectivity ,General Chemistry ,Oxidants ,Biochemistry ,Combinatorial chemistry ,Article ,Catalysis ,Coupling (electronics) ,Colloid and Surface Chemistry ,Benzyl Compounds ,Indans ,Copper catalyzed ,Molecule ,Reactivity (chemistry) ,Selectivity ,Oxidation-Reduction ,Copper - Abstract
Azoles are important motifs in medicinal chemistry, and elaboration of their structures via direct N-H/C-H coupling could have broad utility in drug discovery. The ambident reactivity of many azoles, however, presents significant selectivity challenges. Here, we report a copper-catalyzed method that achieves site-selective cross-coupling of pyrazoles and other N-H heterocycles with substrates bearing (hetero)benzylic C-H bonds. Excellent N-site selectivity is achieved, with the preferred site controlled by the identity of co-catalytic additives. This cross-coupling strategy features broad scope for both the N-H heterocycle and benzylic C-H coupling partners, enabling application of this method to complex molecule synthesis and medicinal chemistry.
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- 2021
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23. DNA damage and oxidant stress activate p53 through differential upstream signaling pathways
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Daan M.K. van Soest, Tobias B. Dansen, Tao Shi, Paulien E. Polderman, and Boudewijn M.T. Burgering
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0301 basic medicine ,Cell cycle checkpoint ,DNA damage ,Apoptosis ,Cell Cycle Proteins ,Ataxia Telangiectasia Mutated Proteins ,Oxidative phosphorylation ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Physiology (medical) ,Humans ,Phosphorylation ,chemistry.chemical_classification ,Reactive oxygen species ,Kinase ,Tumor Suppressor Proteins ,Hydrogen Peroxide ,Oxidants ,Cell biology ,DNA-Binding Proteins ,030104 developmental biology ,chemistry ,Tumor Suppressor Protein p53 ,Signal transduction ,030217 neurology & neurosurgery ,DNA ,DNA Damage - Abstract
Stabilization and activation of the p53 tumor suppressor are triggered in response to various cellular stresses, including DNA damaging agents and elevated Reactive Oxygen Species (ROS) like H2O2. When cells are exposed to exogenously added H2O2, ATR/CHK1 and ATM/CHK2 dependent DNA damage signaling is switched on, suggesting that H2O2 induces both single and double strand breaks. These collective observations have resulted in the widely accepted model that oxidizing conditions lead to DNA damage that subsequently mediates a p53-dependent response like cell cycle arrest and apoptosis. However, H2O2 also induces signaling through stress-activated kinases (SAPK, e.g., JNK and p38 MAPK) that can activate p53. Here we dissect to what extent these pathways contribute to functional activation of p53 in response to oxidizing conditions. Collectively, our data suggest that p53 can be activated both by SAPK signaling and the DDR independently of each other, and which of these pathways is activated depends on the type of oxidant used. This implies that it could in principle be possible to modulate oxidative signaling to stimulate p53 without inducing collateral DNA damage, thereby limiting mutation accumulation in both healthy and tumor tissues.
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- 2021
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24. Evaluation of the Therapeutic Effects of the Hydroethanolic Extract of Portulaca oleracea on Surgical-Induced Peritoneal Adhesion
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Maede Hasanpour, Mohammadreza Mahdinezhad, Hassan Rakhshandeh, Roghayeh Yahyazadeh, Ali Jaafari, Hamed Rajabi, Mehrdad Iranshahi, Sajjad Ehtiati, Vahid Reza Askari, Alireza Ebrahimzadeh-Bideskan, Vafa Baradaran Rahimi, and Nasser Vahdati-Mashhadian
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Male ,Necrosis ,Angiogenesis ,medicine.medical_treatment ,Anti-Inflammatory Agents ,Administration, Oral ,Tissue Adhesions ,Pharmacology ,Antioxidants ,chemistry.chemical_compound ,0302 clinical medicine ,Fibrosis ,Pathology ,RB1-214 ,Peritoneal Lavage ,Postoperative Period ,Immunoassay ,Chromatography ,0303 health sciences ,Neovascularization, Pathologic ,Oxidants ,Malondialdehyde ,Vascular endothelial growth factor ,medicine.anatomical_structure ,Cytokine ,030220 oncology & carcinogenesis ,Cytokines ,Peritoneum ,medicine.symptom ,Research Article ,Article Subject ,Immunology ,Connective tissue ,Portulaca ,Proinflammatory cytokine ,03 medical and health sciences ,Cell Adhesion ,medicine ,Animals ,Rats, Wistar ,030304 developmental biology ,Inflammation ,Ethanol ,Plant Extracts ,business.industry ,Cell Biology ,medicine.disease ,Rats ,Oxidative Stress ,chemistry ,business ,Biomarkers ,Phytotherapy - Abstract
Objective. Peritoneal adhesion (PA) is an abnormal connective tissue that usually occurs between tissues adjacent to damaged organs during processes such as surgery. In this study, the anti-inflammatory and antioxidant effects of Portulaca oleracea (PO) were investigated against postoperative-induced peritoneal adhesion. Methods. Thirty healthy male Wistar rats ( 220 ± 20 g , 6-8 weeks) were randomly divided into four groups: (1) normal, (2) control (induced peritoneal adhesion), and (3) and (4) PO extracts (induced peritoneal adhesion and received 100 or 300 mg/kg/day of PO extract for seven days). Finally, macroscopic and microscopic examinations were performed using different scoring systems and immunoassays in the peritoneal lavage fluid. Results. We found that the levels of adhesion scores and interleukin- (IL-) 1β, IL-6, IL-10, tumour necrosis factor- (TNF-) α, transforming growth factor- (TGF-) β1, vascular endothelial growth factor (VEGF), and malondialdehyde (MDA) were increased in the control group. However, PO extract (100 and 300 mg/kg) notably reduced inflammatory (IL-1β, IL-6, and TNF-α), fibrosis (TGF-β1), angiogenesis (VEGF), and oxidative (MDA) factors, while increased anti-inflammatory cytokine IL-10, antioxidant factor glutathione (GSH), compared to the control group. Conclusion. Oral administration of PO improved postoperational-induced PA by alleviating the oxidative factors, fibrosis, inflammatory cytokines, angiogenesis biomarkers, and stimulating antioxidative factors. Hence, PO can be considered a potential herbal medicine to manage postoperative PA. However, further clinical studies are required to approve the effectiveness of PO.
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- 2021
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25. The protective effects of capsaicin on oxidative damage-induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin in rats
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Neşe Başak Türkmen, Osman Ciftci, Yasemin Şahin, Asli Taslidere, and Muhammed Fatih Dogan
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Male ,Serum ,Polychlorinated Dibenzodioxins ,Antioxidant ,Thiobarbituric acid ,Health, Toxicology and Mutagenesis ,medicine.medical_treatment ,Apoptosis ,oxidative damage ,Toxicology ,medicine.disease_cause ,Antioxidants ,chemistry.chemical_compound ,rat ,Nephrotoxicity ,Modulation ,Tcdd ,biology ,Chemistry ,General Medicine ,Oxidants ,Glutathione ,Liver ,Toxicity ,Level ,medicine.medical_specialty ,Dioxins ,Stress ,Thiobarbituric Acid Reactive Substances ,Exposure ,Superoxide dismutase ,Internal medicine ,Acid ,medicine ,TBARS ,Animals ,Rats, Wistar ,Pharmacology ,Chemical Health and Safety ,Superoxide Dismutase ,Public Health, Environmental and Occupational Health ,dioxin ,Rats ,Oxidative Stress ,Endocrinology ,Capsaicin ,biology.protein ,Corn Oil ,Oxidative stress - Abstract
The present study aimed to investigate the protective role of capsaicin in a rat model of 2,3,7,8-tetracholorodibenzo-p-dioxin (TCDD)-induced toxicity. Exposure to TCDD which is an environmental toxicant causes severe toxic effects in the animal and human tissues. Therefore, the potential protective effect of capsaicin in TCDD-induced organ damage was investigated in rats by measuring thiobarbituric acid reactive substances (TBARS) level, superoxide dismutase (SOD) activity, and glutathione (GSH) level in the heart, liver, and kidney tissues for oxidant/antioxidant balance. Thirty-two healthy adults (250-300 g weight and 3-4 months old) male Wistar albino rats were randomly distributed into four equal groups (n = 8): Control, CAP, TCDD, TCDD + CAP. A dose of 2 mu g/kg TCDD or a dose of 25 mg/kg capsaicin were dissolved in corn oil and orally administered to the rats for 30 days. The results indicated that TCDD-induced oxidative stress by increasing the level of TBARS and by decreasing the levels of GSH, and SOD activity in the tissues of rats. However, capsaicin treatment was significantly decreased TBARS levels and was significantly increased GSH level and SOD activity (p < 0.05). In addition, capsaicin (25 mg/kg) significantly attenuated TCDD-induced histopathological alteration associated with oxidative stress in the heart, liver, and kidney tissues (p < 0.05). As capsaicin regulates oxidative imbalance and attenuates histopathological alterations in the rat tissues, it may be preventing agents in TCDD toxicity.
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- 2021
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26. Correction for: Aucubin exerts anti-osteoporotic effects by promoting osteoblast differentiation
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Xin Liu, Wenqian Lu, Di Wang, Yongfeng Zhang, Yutong Li, Min Hu, and Xinrui Zhang
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Aging ,Iridoid Glucosides ,Osteocalcin ,Apoptosis ,Smad Proteins ,Pharmacology ,Bone and Bones ,Collagen Type I ,Dexamethasone ,Cell Line ,Mice ,chemistry.chemical_compound ,medicine ,Animals ,Humans ,Glucocorticoids ,Aucubin ,Cell Proliferation ,Osteoblasts ,Chemistry ,Correction ,Cell Differentiation ,Osteoblast ,Hydrogen Peroxide ,Cell Biology ,Oxidants ,GA-Binding Protein Transcription Factor ,Oxidative Stress ,medicine.anatomical_structure ,Sp7 Transcription Factor ,Cytokines ,Osteoporosis ,Osteopontin ,Proto-Oncogene Proteins c-akt ,Signal Transduction - Abstract
Osteoporosis is a metabolic disease characterized by reduced osteoblast differentiation and proliferation. Oxidative stress plays a role in the pathogenesis of osteoporosis. Aucubin (AU), an iridoid glycoside, was previously shown to promote osteoblast differentiation. We investigated the effects of AU on MG63 human osteoblast-like cells treated with dexamethasone (Dex) or hydrogen peroxide (H
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- 2021
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27. CityU researchers develop novel photo-oxidation therapy for anticancer treatment.
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Photodynamic therapy, an innovative cancer treatment approach, utilizes photosensitizers to generate reactive oxygen species (ROSs), which when irradiated by light, selectively kill cancer cells. Keywords: Anticancer Agents; Asia; Biotechnology; Cancer; Cancer Therapy; Chalcogens; Chemistry; City University of Hong Kong; Drugs and Therapies; Health and Medicine; Hong Kong; Oncology; Oxidants; Pharmaceuticals; Photodynamic Therapy; Photodynamics; Phototherapy; Protective Agents EN Anticancer Agents Asia Biotechnology Cancer Cancer Therapy Chalcogens Chemistry City University of Hong Kong Drugs and Therapies Health and Medicine Hong Kong Oncology Oxidants Pharmaceuticals Photodynamic Therapy Photodynamics Phototherapy Protective Agents 151 151 1 10/03/23 20231003 NES 231003 2023 OCT 3 (NewsRx) -- By a News Reporter-Staff News Editor at Cancer Weekly -- A research team led by scientists from City University of Hong Kong (CityU) has achieved a significant breakthrough by inventing a new class of near-infrared-activated photo-oxidants that can effectively kill cancer cells without requiring oxygen. [Extracted from the article]
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- 2023
28. OXIDATIVE STRESS AND SERUM S100B LEVELS IN ADOLESCENTS WITH FIRST-EPISODE DRUG-NAIVE UNIPOLAR DEPRESSION
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Sara Bianchi, Eleonora Valentini, Patrizia Moretti, Luigi Maria Pandolfi, Kety Amantini, Giulia Menculini, Mattia Gatto, and Alfonso Tortorella
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Depression scale ,unipolar depression ,adolescent ,S100B ,oxidative stress ,gender ,S100 Calcium Binding Protein beta Subunit ,medicine.disease_cause ,Antioxidants ,chemistry.chemical_compound ,Internal medicine ,Humans ,Medicine ,Child ,Depression (differential diagnoses) ,First episode ,Depressive Disorder ,business.industry ,General Medicine ,Oxidants ,Malondialdehyde ,Oxidative Stress ,Psychiatry and Mental health ,Drug-naïve ,Pharmaceutical Preparations ,chemistry ,Etiology ,Anxiety ,Female ,medicine.symptom ,business ,Oxidative stress ,medicine.drug - Abstract
Background Unipolar depression is common among adolescents and has high recurrence rates. Studies conducted with adults show that oxidative stress plays a role in etiology of depression but studies with adolescent patients are limited. In addition, baseline S100B level in adult patients with depression is considered as a marker of response to treatment. The purpose of this study was to measure the levels of serum S100B, Malondialdehyde (MDA), total oxidant status (TOS), and total antioxidant status (TAS), which have not been previously investigated in adolescent patients with first-episode, drug-naive unipolar depression, and to investigate the relationship of these parameters with disease severity and patient-specific variables. Subjects and methods This study was conducted with 37 adolescents diagnosed with unipolar depression and 37 healthy peers. Participants were asked to fill out the Beck Depression Scale, Screen for Child Anxiety Related Disorders, and suicide probability questionnaires. After this procedure, 5 cc blood was collected from the adolescents and serum S100B, MDA, TOS, and OSI levels measured. Results Serum S100B, MDA, TOS, and OSI levels were higher and TAS level was lower in patients than their healthy peers. There was no relationship between the patients' severity of depression or suicide probability and these parameters. The serum S100B, MDA, TOS, and OSI levels of female patients were higher than their healthy peers, but the TAS level was not different. Male patients had higher TOS and OSI levels and lower TAS levels than their healthy peers. Conclusions The results show that increased serum S100B, MDA, TOS and OSI levels may contribute to etiology of depression regardless of gender. The gender-specific increase in S100B and MDA levels, which were significantly increased in female adolescent patients but not in males, should be supported by further follow-up studies.
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- 2021
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29. Nickel-Catalyzed Decarboxylative Cross-Coupling of Bicyclo[1.1.1]pentyl Radicals Enabled by Electron Donor–Acceptor Complex Photoactivation
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Viktor C. Polites, Gary A. Molander, Sebastian Keess, Shorouk O. Badir, and Anais Jolit
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Decarboxylative cross-coupling ,Electrons ,Electron donor ,Pentanes ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Article ,Catalysis ,chemistry.chemical_compound ,Nucleophile ,Nickel ,Physical and Theoretical Chemistry ,Molecular Structure ,Bicyclic molecule ,010405 organic chemistry ,Aryl ,Organic Chemistry ,Esters ,Oxidants ,Combinatorial chemistry ,Acceptor ,Carbon ,0104 chemical sciences ,Propellane ,chemistry ,Oxidation-Reduction - Abstract
The use of bicyclo[1.1.l]pentanes (BCPs) as para-disubstituted aryl bioisosteres has gained considerable momentum in drug development programs. Carbon–carbon bond formation via transition-metal-mediated cross-coupling represents an attractive strategy to generate BCP–aryl compounds for late-stage functionalization, but these typically require reactive organometallics to prepare BCP nucleophiles on demand from [l.1.l]propellane. In this study, the synthesis and Ni-catalyzed functionalization of BCP redox-active esters with (hetero)aryl bromides via the action of a photoactive electron donor–acceptor complex are reported.
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- 2021
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30. Cystine reduces tight junction permeability and intestinal inflammation induced by oxidative stress in Caco-2 cells
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Hiroyuki Kato, Tatsuya Hasegawa, Ami Mizugaki, Hitoshi Murakami, and Yoshiko Inoue
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0301 basic medicine ,Cell Membrane Permeability ,Clinical Biochemistry ,Inflammation ,medicine.disease_cause ,Systemic inflammation ,Biochemistry ,Tight Junctions ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,Humans ,Cysteine ,Claudin-4 ,Intestinal Mucosa ,Intestinal barrier ,Barrier function ,Tight junction ,Organic Chemistry ,Hydrogen Peroxide ,Glutathione ,Oxidants ,Cell biology ,Oxidative Stress ,030104 developmental biology ,chemistry ,Permeability (electromagnetism) ,Paracellular transport ,Cystine ,Original Article ,030211 gastroenterology & hepatology ,Caco-2 Cells ,medicine.symptom ,Oxidative stress - Abstract
Intestinal oxidative stress produces pro-inflammatory cytokines, which increase tight junction (TJ) permeability, leading to intestinal and systemic inflammation. Cystine (Cys2) is a substrate of glutathione (GSH) and inhibits inflammation, however, it is unclear whether Cys2 locally improves intestinal barrier dysfunction. Thus, we investigated the local effects of Cys2 on oxidative stress-induced TJ permeability and intestinal inflammatory responses. Caco-2 cells were cultured in a Cys2-supplemented medium for 24 h and then treated with H2O2 for 2 h. We assessed TJ permeability by measuring transepithelial electrical resistance and the paracellular flux of fluorescein isothiocyanate–dextran 4 kDa. We measured the concentration of Cys2 and GSH after Cys2 pretreatment. The mRNA expression of pro-inflammatory cytokines was assessed. In addition, the levels of TJ proteins were assessed by measuring the expression of TJ proteins in the whole cells and the ratio of TJ proteins in the detergent-insoluble fractions to soluble fractions (IS/S ratio). Cys2 treatment reduced H2O2-induced TJ permeability. Cys2 did not change the expression of TJ proteins in the whole cells, however, suppressed the IS/S ratio of claudin-4. Intercellular levels of Cys2 and GSH significantly increased in cells treated with Cys2. Cys2 treatment suppressed the mRNA expression of pro-inflammatory cytokines, and the mRNA levels were significantly correlated with TJ permeability. In conclusion, Cys2 treatment locally reduced oxidative stress-induced intestinal barrier dysfunction possively due to the mitigation of claudin-4 dislocalization. Furthermore, the effect of Cys2 on the improvement of intestinal barrier function is related to the local suppression of oxidative stress-induced pro-inflammatory responses.
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- 2021
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31. Investigating the effect of hydrogen peroxide as an electron acceptor in increasing the capability of slurry photocatalytic process in dye removal
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Bita Ayati, Roxana Rahmati, and Behnam Nayebi
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Environmental Engineering ,Hydrogen ,Inorganic chemistry ,kinetic ,chemistry.chemical_element ,Electrons ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,Environmental technology. Sanitary engineering ,Catalysis ,acid orange 7 ,chemistry.chemical_compound ,energy consumption ,Oxidizing agent ,Hydrogen peroxide ,TD1-1066 ,0105 earth and related environmental sciences ,Water Science and Technology ,chemistry.chemical_classification ,Hydrogen Peroxide ,cod ,Electron acceptor ,Oxidants ,021001 nanoscience & nanotechnology ,Kinetics ,chemistry ,Photocatalysis ,Slurry ,zno ,Degradation (geology) ,0210 nano-technology ,Azo Compounds - Abstract
The hydrogen peroxide role in photocatalytic degradation of an anionic azo dye, Acid Orange 7 (AO7), was investigated in a slurry reactor. Commercial ZnO nanoparticles with an average size between 10 to 30 nm were used as catalysts. Optimum conditions for different parameters, including dye concentration (10–100 mg/L), catalyst concentration (0.1–0.5 g/L), and pH (5–10), were determined first in the absence of H2O2. Changes in the COD were measured for the optimum condition. The impact of adding hydrogen peroxide at different concentrations to the system operating at optimum conditions was investigated. It was observed that 0.416 mM hydrogen peroxide increased the system's efficiency and decreased reaction time by 40 min. The reaction followed first-order kinetic. Hydrogen peroxide alone did not contribute to oxidizing the contaminant, and its positive impact was attributed to decreasing electron-hole recombination in the photocatalytic process. Not only can the hydrogen peroxide-assisted photocatalytic process decrease retention time in treatment units, but it can also result in more contaminant degradation. Therefore, it can reduce the treatment cost. HIGHLIGHTS Improving the efficiency of the slurry photocatalytic process by adding H2O2.; Promoting the process's rate and reaction kinetics’ constants four times by adding 2.5 mM of H2O2.; Determining optimum concentration using energy consumption reaction in order to conduct the research in the minimum energy usage condition.
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- 2021
32. Compartmentally scavenging hepatic oxidants through AMPK/SIRT3-PGC1α axis improves mitochondrial biogenesis and glucose catabolism
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Ben Lai, Liang Qiao, Meiling Wu, Shanlin Liu, Dongyun Shi, Chunwang Zhang, Jiankang Liu, Mengdan Xie, and Yuansheng Zhen
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0301 basic medicine ,medicine.medical_specialty ,Glucose uptake ,AMP-Activated Protein Kinases ,Biochemistry ,Diabetes Mellitus, Experimental ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Downregulation and upregulation ,Sirtuin 3 ,Physiology (medical) ,Internal medicine ,Diabetes mellitus ,medicine ,Animals ,Organelle Biogenesis ,Catabolism ,Chemistry ,Type 2 Diabetes Mellitus ,AMPK ,Oxidants ,medicine.disease ,Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ,Glucose ,030104 developmental biology ,Endocrinology ,Diabetes Mellitus, Type 2 ,Liver ,Gluconeogenesis ,Mitochondrial biogenesis ,030217 neurology & neurosurgery - Abstract
Early treatment can prevent the occurrence of diabetes; however, there are few pharmacological treatment strategies to date. The liver is a major metabolic organ, and hepatic glucose homeostasis is dysregulated in type 1 and type 2 diabetes mellitus. However, the potential of specifically targeting the liver to prevent diabetes has not been fully exploited. In this study, we found that compartmentally inhibiting hepatic oxidants by nano-MitoPBN, a liver mitochondrial-targeting ROS scavenger, could effectively prevent diabetes. Our results demonstrated that nano-MitoPBN reversed the downregulation of PGC-1α and the enhanced gluconeogenesis in the livers of diabetic mice. PGC-1α, through an AMPK- and SIRT3-mediated mechanism, promoted mitochondrial biogenesis, increased the number of mitochondria, and enhanced the rate of aerobic oxidation, leading to decreased glucose levels in the blood by increasing glucose uptake and catabolism in the liver. Moreover, the increase in PGC-1α activity did not promote the activation of gluconeogenesis. Our study demonstrated that by regulating the redox balance of liver mitochondria in the early stage of diabetes, PGC-1α could selectively inhibit gluconeogenesis in the liver and promote hepatic mitochondrial function, which accelerated the catabolism of hepatic glucose and reduced blood glucose. Thus, glucose tolerance can be normalized through only three weeks of intervention. Our results showed that nano-MitoPBN could effectively prevent diabetes in a short period of time, highlighting the effectiveness and importance of early intervention for diabetes and suggesting the potential advantages of hepatic mitochondrial targeting oxidants nano-inhibitors in the prevention and early treatment of diabetes.
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- 2021
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33. Circulating trimethylamine N-oxide in association with diet and cardiometabolic biomarkers: an international pooled analysis
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Robert E. Gerszten, Ioanna Tzoulaki, Myriam Fornage, Wei Zheng, Demetrius Albanes, Ibrahim Karaman, Jae Jeong Yang, Lynne E. Wagenknecht, Charles E. Matthews, Sei Harada, Cristina Menni, David M. Herrington, Cornelia M. Ulrich, Paul Elliott, Steven C. Moore, Jennifer Ose, Marta Guasch-Ferré, Danxia Yu, Katie A. Meyer, Hui Cai, Nicholette D. Palmer, Thomas J. Wang, Huilian Zhu, Xiao-Ou Shu, Qiuyin Cai, and Heather Eliassen
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Adult ,Male ,0301 basic medicine ,medicine.medical_specialty ,Internationality ,Saturated fat ,Population ,Medicine (miscellaneous) ,Trimethylamine N-oxide ,030204 cardiovascular system & hematology ,Global Health ,09 Engineering ,Cardiovascular Physiological Phenomena ,Methylamines ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,cardiovascular disease ,Internal medicine ,medicine ,Humans ,education ,11 Medical and Health Sciences ,Creatinine ,education.field_of_study ,Nutrition and Dietetics ,trimethylamine N-oxide ,Nutrition & Dietetics ,Cholesterol ,business.industry ,Oxidants ,Gastrointestinal Microbiome ,Original Research Communications ,030104 developmental biology ,Endocrinology ,chemistry ,Plant protein ,Consortium of Metabolomics Studies ,Red meat ,biomarker ,Female ,Glycated hemoglobin ,Energy Metabolism ,diet ,business ,Biomarkers - Abstract
BACKGROUND: Trimethylamine N-oxide (TMAO), a diet-derived, gut microbial-host cometabolite, has been linked to cardiometabolic diseases. However, the relations remain unclear between diet, TMAO, and cardiometabolic health in general populations from different regions and ethnicities. OBJECTIVES: To examine associations of circulating TMAO with dietary and cardiometabolic factors in a pooled analysis of 16 population-based studies from the United States, Europe, and Asia. METHODS: Included were 32,166 adults (16,269 white, 13,293 Asian, 1247 Hispanic/Latino, 1236 black, and 121 others) without cardiovascular disease, cancer, chronic kidney disease, or inflammatory bowel disease. Linear regression coefficients (β) were computed for standardized TMAO with harmonized variables. Study-specific results were combined by random-effects meta-analysis. A false discovery rate
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- 2021
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34. Photochemical Regioselective C(sp3)–H Amination of Amides Using N-Haloimides
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Maria Victoria Cooke, Sébastien Laulhé, Joseph Elmasry, Lei Pan, and Tomas Osccorima
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chemistry.chemical_classification ,Exergonic reaction ,Molecular Structure ,Base (chemistry) ,010405 organic chemistry ,Organic Chemistry ,chemistry.chemical_element ,Regioselectivity ,Oxidants ,010402 general chemistry ,Photochemistry ,Amides ,01 natural sciences ,Biochemistry ,Article ,0104 chemical sciences ,Oxidants, Photochemical ,Energy profile ,chemistry ,Lithium ,Physical and Theoretical Chemistry ,Amination ,Visible spectrum - Abstract
A metal-free regioselective C(sp(3))–H amination of amides using N-haloimides in the presence of lithium tert-butoxide and visible light is presented herein. This photoexcited approach is straightforward, and it aminates a wide variety of amides under mild conditions without the use of photocatalysts, external radical initiators, or oxidants. A halogen-bonded intermediate between the tert-butoxide base and the N-haloimide is proposed to be responsible for the increased photoreactivity. Calculations show that the formation of this electron donor–acceptor complex presents an exergonic energy profile.
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- 2021
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35. Astaxanthin Reduces the Severity of Intestinal Damage in a Neonatal Rat Model of Necrotizing Enterocolitis
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Veli Korkmaz, Hasan Akduman, Nurdan Dinlen Fettah, Başak Kaya Gürsoy, Tugba Taskin Turkmenoglu, Cüneyt Tayman, Murat Caglayan, and Filiz Akduman
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Antioxidant ,medicine.medical_treatment ,Antioxidants ,Superoxide dismutase ,Andrology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Enterocolitis, Necrotizing ,Astaxanthin ,medicine ,Animals ,Rats, Wistar ,Saline ,030304 developmental biology ,0303 health sciences ,biology ,Caspase 3 ,Tumor Necrosis Factor-alpha ,Superoxide Dismutase ,business.industry ,Obstetrics and Gynecology ,Glutathione ,Oxidants ,medicine.disease ,digestive system diseases ,Rats ,Disease Models, Animal ,Animals, Newborn ,Advanced Oxidation Protein Products ,chemistry ,030220 oncology & carcinogenesis ,Myeloperoxidase ,Pediatrics, Perinatology and Child Health ,Necrotizing enterocolitis ,biology.protein ,Tumor necrosis factor alpha ,business - Abstract
Objective This study aimed to ascertain the effects of astaxanthin (ASX) in an experimental necrotizing enterocolitis (NEC) model using rat pups. Study Design Forty-two pups born from five Wistar albino rats were randomly divided into three groups as the control group, NEC + placebo (saline), and NEC + ASX. Pups in the NEC + ASX group were given 100 mg/kg/day oral ASX from day 1 to day 4 of the study. Saline of 2 mL/kg was given to the NEC + placebo group. Histopathological, immunohistochemical (caspase-3), and biochemical evaluations including the total antioxidant status (TAS), total oxidant status (TOS), superoxide dismutase (SOD), glutathione (GSH), lipid hydroperoxide (LPO), 8-hydroxydeoxyguanosine (8-OHdG), advanced oxidation protein products (AOPP), myeloperoxidase (MPO), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and nuclear factor erythroid 2–related factor 2 (Nfr-2) activities were all performed. Results A better survival rate and weight gain were demonstrated in the NEC + ASX group (p Conclusion ASX treatment has been shown to effectively reduce the severity of intestinal damage in NEC due to its antioxidant, anti-inflammatory, and antiapoptotic properties. Key Points
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- 2021
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36. Avocado/soy unsaponifiables can redress the balance between serum antioxidant and oxidant levels in patients with osteoarthritis: a double-blind, randomized, placebo-controlled, cross-over study
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Saeed Basereh, Gholam Hossein Alishiri, Ali Zaree Mahmoudabadi, Mohsen Korani, Zohreh Jangravi, and Mehdi Saberi
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0301 basic medicine ,medicine.medical_specialty ,Antioxidant ,medicine.medical_treatment ,Osteoarthritis ,medicine.disease_cause ,Placebo ,Gastroenterology ,Antioxidants ,Superoxide dismutase ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Double-Blind Method ,Internal medicine ,Humans ,Plant Oils ,Medicine ,030203 arthritis & rheumatology ,Cross-Over Studies ,biology ,Persea ,business.industry ,Glutathione ,Oxidants ,medicine.disease ,Crossover study ,Oxidative Stress ,Treatment Outcome ,030104 developmental biology ,Complementary and alternative medicine ,chemistry ,Catalase ,biology.protein ,Soybeans ,business ,Oxidative stress - Abstract
Objectives Osteoarthritis (OA) is an inflammatory disorder of the joint characterized by pain and stiffness. Oxidative stress plays an important role in pathogenesis of OA. We aimed to evaluate the effects of avocado/soy unsaponifiables (ASU) compound on serum antioxidant and oxidative stress in patients with Osteoarthritis. Methods A double-blind, randomized, placebo-controlled, cross-over trial was performed. Fourty patients with osteoarthritis were randomized to two different sequences: 1) DP: received ASU for three months followed by three months placebo, 2) PD: received placebo for the first three months followed by three months ASU. The oxidant statue was evaluated by measurement of serum malonldialdehyde (MDA). The total antioxidant capacity (TAC), reduced glutathione (GSH) and antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) were also assessed. Results Mean serum of MDA level as a marker of oxidative stress significantly decreased in all patients after three months treatment with ASU (4.46 ± 0.11 nmol/L) compare with baseline and placebo levels (5 ± 0.15 and 5.82 ± 0.12 nmol/L respectively) (p0.05). Conclusions These data showed that Avocado/Soy Unsaponifiable can be an effective supplement in treatment of osteoarthritis through the control of the balance between antioxidant and oxidant molecular markers.
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- 2021
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37. Fucoxanthin alters the apelin-13/APJ pathway in certain organs of γ-irradiated mice
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Mohamed K. Abdel-Rafei, Noura M Thabet, Nermeen M El Bakary, Ghada El Tawill, Khaled Shaaban Azab, and Neama M El Fatih
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Necrosis ,Antioxidant ,Health, Toxicology and Mutagenesis ,medicine.medical_treatment ,Fucoxanthin ,Xanthophylls ,Kidney ,Antioxidants ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,chemistry.chemical_classification ,0303 health sciences ,Apelin Receptors ,Radiation ,Glutathione peroxidase ,NF-kappa B ,Apelin-13/APJ ,Malondialdehyde ,Oxidants ,Apelin ,medicine.anatomical_structure ,Liver ,Matrix Metalloproteinase 9 ,Organ Specificity ,030220 oncology & carcinogenesis ,Intercellular Signaling Peptides and Proteins ,Matrix Metalloproteinase 2 ,medicine.symptom ,MMP-9 ,Whole-Body Irradiation ,Signal Transduction ,medicine.medical_specialty ,α-7nAchR ,03 medical and health sciences ,Lactate dehydrogenase ,Internal medicine ,medicine ,Animals ,Radiology, Nuclear Medicine and imaging ,Fundamental Radiation Science ,030304 developmental biology ,Inflammation ,Tissue Inhibitor of Metalloproteinase-1 ,L-Lactate Dehydrogenase ,Monocyte ,Glutathione ,γ-radiation ,Endocrinology ,chemistry ,Gamma Rays ,AcademicSubjects/SCI00960 ,AcademicSubjects/MED00870 - Abstract
Apelin-13 and APJ are implicated in different key physiological processes. This work aims at exploring the radioprotective effect of fucoxanthin (FX) on γ-radiation (RAD)-induced changes in the apelin-13/APJ pathway, which causes damage in the liver, kidney, lung and spleen of mice. Mice were administered FX (10 mg kg–1 day–1, i.p) and exposed to γ-radiation (2.5 Gy week–1) for four consecutive weeks. The treatment of irradiated mice by FX resulted in a significant amendment in protein expression of the apelin-13/APJ/NF-κB signalling pathway concurrently with reduced hypoxia (hypoxia-inducible factor-1α), suppressed oxidative stress marker (malondialdehyde), enhanced antioxidant defence mechanisms (reduced glutathione and glutathione peroxidase), a modulated inflammatory response [interleukin-6 (IL-6), monocyte chemoattractant protein-1, IL-10 and α-7-nicotinic acetylcholine receptor) and ameliorated angiogenic regulators [matrix metalloproteinase (MMP-2), MMP-9 and tissue inhibitor of metalloproteinase-1), as well as the tissue damage indicator (lactate dehydrogenase) in organ tissues. In addition, there were significant improvement in serum inflammatory markers tumour necrosis factor-α, IL-10, IL-1β and C-reactive protein compared with irradiated mice. The histopathological investigation of the FX + RAD organ tissues support the biochemical findings where the improvements in the tissues’ architecture were obvious when compared with those of RAD. FX was thus shown to have a noticeable radioprotective action mediated through its regulatory effect on the apelin-13/APJ/NF-κB signalling pathway attributed to its antioxidant and anti-inflammatory activity that was reflected in different physiological processes. It could be recommended to use FX in cases of radiation exposure to protect normal tissues.
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- 2021
38. A Unifying Bioinspired Synthesis of (−)-Asperaculin A and (−)-Penifulvin D
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Anders Sundin, Miguel Lopez-Tena, Daniel Strand, and Ian R. George
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Ketone ,Letter ,Substituent ,Ether ,Cyanation ,010402 general chemistry ,01 natural sciences ,Biochemistry ,chemistry.chemical_compound ,Lactones ,Physical and Theoretical Chemistry ,Cyanohydrin ,chemistry.chemical_classification ,Biological Products ,Molecular Structure ,010405 organic chemistry ,Aryl ,Organic Chemistry ,Leaving group ,Hydrogen Peroxide ,Ketones ,Oxidants ,Combinatorial chemistry ,0104 chemical sciences ,chemistry ,Selectivity ,Sesquiterpenes - Abstract
The first syntheses of the isomeric dioxafenestrene natural products (-)-asperaculin A and (-)-penifulvin D are reported. Each target is formed selectively by choice of oxidant in a final divergent bioinspired Baeyer-Villiger (BV) reaction. Density functional theory calculations reveal that electrostatic interactions between the oxidant leaving group and the lactone motif accounts for a reversal of selectivity with H2O2/H3O+ compared to peracids. Synthetic features include forging the polycyclic carbon framework with a diastereoselective meta-photocycloaddition biased by an ether substituent at the aryl α-position. The encumbered tertiary alcohol was installed by cyanation of a ketone intermediate followed by nonaqueous hydrolysis of the resulting delicate cyanohydrin.
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- 2021
39. Evaluation of saliva glutathione, glutathione peroxidase, and malondialdehyde levels in head-neck radiotherapy patients
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Gözde Derindağ, Hayati Murat Akgül, Halil Ibrahim Ozkan, Ahmet Kiziltunc, Hilal Kiziltunc Ozmen, and Nilgun Akgul
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Lipid-Peroxidation ,malondialdehyde ,Adult ,Male ,Saliva ,medicine.medical_specialty ,Antioxidant ,medicine.medical_treatment ,medicine.disease_cause ,Gastroenterology ,Article ,Antioxidants ,chemistry.chemical_compound ,head and neck neoplasms ,Internal medicine ,medicine ,Biomarkers, Tumor ,Humans ,Periodontitis ,radiotherapy ,Aged ,chemistry.chemical_classification ,saliva ,Glutathione Peroxidase ,business.industry ,Antioxidant Status ,Glutathione peroxidase ,General Medicine ,Glutathione ,Middle Aged ,Malondialdehyde ,Oxidants ,Radiation therapy ,Precancer ,Oxidative Stress ,chemistry ,Oral-Cancer ,Mann–Whitney U test ,Female ,business ,Leukoplakia ,Biomarkers ,Oxidative stress - Abstract
Background/aim: It is believed that radiotherapy has important effects on oxidant/antioxidant systems. Oxidative stress occurs when the balance between oxidant formation and antioxidant defense is disrupted in favor of oxidants. The aim of this study was to determine the biochemical changes in saliva pre-and postradiotherapy in head-neck radiotherapy patients and to find out the effects of radiation on glutathione (GSH), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) levels in saliva. Materials and methods: This study included 16 patients undergoing head-neck radiotherapy in Atat & uuml;rk University Research Hospital. The levels of GSH, GSH-Px, and MDA were measured in saliva samples taken from the patients pre-and postradiotherapy. The same biochemical parameters were also measured in saliva samples from 30 healthy individuals who did not undergo head-neck radiotherapy. The data obtained were analyzed using the paired t-test and the Mann-Whitney U test. Results: When the levels of GSH (P > 0.05), GSH-Px (P > 0.05), and MDA (P < 0.05) in saliva were compared pre-and postradiotherapy in the patient group, the only significant increase was detected in the MDA level postradiotherapy. When the pre-and postradiotherapy levels of saliva GSH (P < 0.01, P < 0.001, respectively), GSH-Px (P > 0.05, P < 0.05, respectively), and MDA (P < 0.01, P < 0.001, respectively) were compared with those of the control group, it was revealed that the GSH level was significantly lower and the MDA level was significantly higher in both pre-and postradiotherapy compared to the control group. Also, only the postradiotherapy saliva GSH-Px level was found to be significantly lower than the control group. Conclusion: These findings show that the changes in saliva GSH, GSH-Px, and MDA levels in patients with head-neck malignity intensified due to radiation.
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- 2021
40. Amelioration of Pterostilbene Antiproliferative, Proapoptotic, and Oxidant Potentials in Human Breast Cancer MCF7 Cells Using Zein Nanocomposites
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Hussam I Kutbi, Dalia Farag El-Telbany, and Ahmed K. Kammoun
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pterostilbene ,Pterostilbene ,MCF7 cells ,Zein ,Glutathione reductase ,Biophysics ,Pharmaceutical Science ,Antineoplastic Agents ,Apoptosis ,Breast Neoplasms ,Bioengineering ,Nanocomposites ,Biomaterials ,chemistry.chemical_compound ,International Journal of Nanomedicine ,Annexin ,Stilbenes ,Drug Discovery ,medicine ,Humans ,Particle Size ,Cytotoxicity ,IC50 ,Original Research ,nanospheres ,Chemistry ,Organic Chemistry ,Cancer ,General Medicine ,Oxidants ,medicine.disease ,Molecular biology ,In vitro ,MCF-7 Cells ,Oxidation-Reduction ,phototherapy - Abstract
Hussam I Kutbi,1 Ahmed K Kammoun,2 Dalia Farag El-Telbany3 1Department of Pharmacy Practice, Faculty of Pharmacy, King Abdulaziz University, Jeddah, 21589, Saudi Arabia; 2Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Jeddah, 21589, Saudi Arabia; 3Department of Pharmaceutics, Faculty of Pharmacy, Modern University for Technology and Information (MTI), Cairo, 11571, EgyptCorrespondence: Dalia Farag El-TelbanyDepartment of Pharmaceutics, Faculty of Pharmacy, Modern University for Technology and Information (MTI) University, El-Hadaba El-Wosta, 5th District, Mokatam, Cairo, 11571, EgyptTel +20-11-1996-6617Fax +20227294500Email dalia.altelbany@gmail.comPurpose: This study aimed to explain the influence of zein nanosphere (ZN NS) formulation on the pharmacotherapeutic profile of PTS in MCF7 cells.Methods: Liquid–liquid phase separation was used to formulate PTS-ZN NSs. The formulations developed were evaluated for particle-size analysis, encapsulation efficiency, and in vitro diffusion. Also, assays of cytotoxicity, uptake, cell-cycle progression, annexin V, apoptotic gene mRNA expression and biochemical assays were carried out.Results: The PTS-ZN NS formulation selected showed 104.5± 6.2 nm, 33.4± 1.8 mV, 95.1%± 3.6%, and 89.1%± 2.65% average particle size, zeta-potential, encapsulation efficiency and in vitro diffusion, respectively. With MCF7 cells, IC50 was reduced approximately 15-fold, with increased cellular uptake, accumulation in the G2/M phase, increased percentage of cells in the pre-G1 phase, amelioration of early and late apoptosis, raised mRNA expression of CASP3 and CASP7, lower expression of cyclin-CDK1, and enhanced oxidant potential through decreased glutathione reductase (GR) activity, and enhanced reactive oxygen–species generation and lipid-peroxidation products.Conclusion: PTS-ZN NSs indicated enhanced antiproliferative, proapoptotic, and oxidant potential toward MCF7 cells compared to free PTS. Ameliorated results of nanosized carriers, cellular uptake, and sustained diffusion may contribute to these outcomes.Keywords: phototherapy, pterostilbene, MCF7 cells, nanospheres, zein
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- 2021
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41. Physical plasma-derived oxidants sensitize pancreatic cancer cells to ferroptotic cell death
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Wim Vanden Berghe, Evelien Smits, Emilie Logie, Angela Privat-Maldonado, Priyanka Shaw, Naresh Kumar, Annemie Bogaerts, Claudina Perez-Novo, and Sylvia Dewilde
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0301 basic medicine ,Programmed cell death ,HMOX1 ,NF-E2-Related Factor 2 ,Serine threonine protein kinase ,GPX4 ,Biochemistry ,03 medical and health sciences ,0302 clinical medicine ,Physiology (medical) ,Pancreatic cancer ,medicine ,Humans ,Kinome ,Biology ,CAMK ,Kelch-Like ECH-Associated Protein 1 ,Cell Death ,Chemistry ,Kinase ,Oxidants ,medicine.disease ,Pancreatic Neoplasms ,030104 developmental biology ,Cancer research ,Human medicine ,Reactive Oxygen Species ,030217 neurology & neurosurgery - Abstract
Despite modern therapeutic advances, the survival prospects of pancreatic cancer patients remain poor, due to chemoresistance and dysregulated oncogenic kinase signaling networks. We applied a novel kinome activity-mapping approach using biological peptide targets as phospho-sensors to identify vulnerable kinase dependencies for therapy sensitization by physical plasma. Ser/Thr-kinome specific activity changes were mapped upon induction of ferroptotic cell death in pancreatic tumor cells exposed to reactive oxygen and nitrogen species of plasma-treated water (PTW). This revealed a broad kinome activity response involving the CAMK, the AGC and CMGC family of kinases. This systems-level kinome network response supports stress adaptive switches between chemoresistant anti-oxidant responses of Kelch-like ECH-associated protein 1 (KEAP1)/Heme Oxygenase 1 (HMOX1) and ferroptotic cell death sensitization upon suppression of Nuclear factor (erythroid derived 2)-like 2 (NRF2) and Glutathione peroxidase 4 (GPX4). This is further supported by ex vivo experiments in the chicken chorioallantoic membrane assay, showing decreased GPX4 and Glutathione (GSH) expression as well as increased lipid peroxidation, along with suppressed BxPC-3 tumor growth in response to PTW. Taken all together, we demonstrate that plasma treated water-derived oxidants sensitize pancreatic cancer cells to ferroptotic cell death by targeting a NRF2-HMOX1-GPX4 specific kinase signaling network.
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- 2021
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42. Sodium iodate induces ferroptosis in human retinal pigment epithelium ARPE-19 cells
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Meng Yu, Libo He, Yang Liu, Yuling Ying, Zihuai Tang, Jinye Dang, Li Yang, Weiyan Wang, Arman Ali Shah, Ke Liu, Mengli Yan, and Binghua Liu
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Cell death ,Cancer Research ,Programmed cell death ,Necroptosis ,Iron ,Immunology ,Iodates ,Retinal Pigment Epithelium ,GPX4 ,Article ,Cell Line ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,medicine ,Ferroptosis ,Humans ,Cysteine ,lcsh:QH573-671 ,Sodium iodate ,Retinal pigment epithelium ,Deferoxamine mesylate ,Disease model ,lcsh:Cytology ,Cell Biology ,Glutathione ,Oxidants ,Cell biology ,Oxidative Stress ,medicine.anatomical_structure ,chemistry ,Lipid Peroxidation ,Reactive Oxygen Species ,Intracellular - Abstract
Sodium iodate (SI) is a widely used oxidant for generating retinal degeneration models by inducing the death of retinal pigment epithelium (RPE) cells. However, the mechanism of RPE cell death induced by SI remains unclear. In this study, we investigated the necrotic features of cultured human retinal pigment epithelium (ARPE-19) cells treated with SI and found that apoptosis or necroptosis was not the major death pathway. Instead, the death process was accompanied by significant elevation of intracellular labile iron level, ROS, and lipid peroxides which recapitulated the key features of ferroptosis. Ferroptosis inhibitors deferoxamine mesylate (DFO) and ferrostatin-1(Fer-1) partially prevented SI-induced cell death. Further studies revealed that SI treatment did not alter GPX4 (glutathione peroxidase 4) expression, but led to the depletion of reduced thiol groups, mainly intracellular GSH (reduced glutathione) and cysteine. The study on iron trafficking demonstrated that iron influx was not altered by SI treatment but iron efflux increased, indicating that the increase in labile iron was likely due to the release of sequestered iron. This hypothesis was verified by showing that SI directly promoted the release of labile iron from a cell-free lysate. We propose that SI depletes GSH, increases ROS, releases labile iron, and boosts lipid damage, which in turn results in ferroptosis in ARPE-19 cells.
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- 2021
43. The effects of doxapram on haematology, serum biochemical parameters and erythrocyte oxidant/ antioxidant status in dogs anaesthetized with propofol
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Bahman Mosallanejad, Hadi Naddaf, Seyedeh Misagh Jalali, Soroush Sabiza, and Ali Baniadam
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Erythrocytes ,Sedation ,medicine.medical_treatment ,O/A status ,Antioxidants ,Acepromazine ,chemistry.chemical_compound ,Dogs ,medicine ,Animals ,biochemistry ,Saline ,Anesthetics ,doxapram ,Creatinine ,Hematologic Tests ,lcsh:Veterinary medicine ,General Veterinary ,propofol ,business.industry ,Albumin ,Red blood cell distribution width ,Original Articles ,Doxapram ,Oxidants ,chemistry ,Anesthesia ,dog ,haematology ,lcsh:SF600-1100 ,Central Nervous System Stimulants ,Original Article ,medicine.symptom ,Propofol ,business ,Blood Chemical Analysis ,medicine.drug - Abstract
The present prospective randomized experimental study was designed to determine the effects of doxapram on haematological, serum biochemical and antioxidant status in dogs after propofol anaesthesia. Twenty‐four healthy male mixed breed dogs, aged 1–2 years, weighing 20.4 ± 2.6 kg was studied. Each dog was anaesthetized twice, with at least one week for washout. Animals were sedated with acepromazine (0.1 mg/kg) intramuscularly. Forty minutes later, anaesthesia was induced using intravenous (IV) propofol (4 mg/kg) titration and maintained for 30 min by propofol (0.2 mg kg−1 min−1). After propofol was discontinued, doxapram (2 mg/kg) hydrochloride was administrated IV in PD treatment while an equal volume of saline was administrated in PS treatment. Blood parameters were analysed in four times: immediately before sedation (T1), after treatment (T2), after complete recovery (T3) and 24 hr later (T4). Haematological assessments revealed no significant difference between treatments except in haematocrit which was significantly reduced at T4 (24 hr later) in PD. A decreasing trend of all haematological variables was observed after doxapram administration until recovery, except monocyte, mean corpuscular haemoglobin, red blood cell distribution width and platelet count. Serum urea, creatinine, glucose, cholesterol, direct bilirubin concentration and alanine aminotransferase activity were not changed following doxapram administration compared to the PS treatment. After doxapram administration, Creatinine (T3), Albumin (T2) and Protein (T2 & T3) decreased while Glucose (T2 & T3) and BT (T3) increased. Antioxidant parameters measured showed no difference between treatments or time. Doxapram (2 mg/kg) IV did not induce any major negative effects on haematological, serum biochemical variables and oxidant/antioxidant status in dogs after propofol anaesthesia., The present prospective randomized experimental study was designed to determine the effects of doxapram on hematological, serum biochemical and antioxidant status in dogs after propofol anesthesia. Twenty four healthy male mixed breed dogs were studied. Doxapram (2 mg kg‐1) IV did not induce any major negative effects on hematological, serum biochemical variables and oxidant/antioxidant status in dogs after propofol anaesthesia.
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- 2021
44. Protective Effect of Mitochondrially Targeted Peptide Against Oxidant Injury of Cone Photoreceptors Through Preventing Necroptosis Pathway
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Yuan Ren, Zejun Chen, Yun Xu, Ruixue Zhang, Zhuoya Quan, Beilei He, and Yuan He
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0301 basic medicine ,Programmed cell death ,Necrosis ,Necroptosis ,Biomedical Engineering ,Pharmaceutical Science ,Medicine (miscellaneous) ,Apoptosis ,Bioengineering ,Pharmacology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Night vision ,medicine ,Animals ,General Materials Science ,Propidium iodide ,chemistry.chemical_classification ,Reactive oxygen species ,business.industry ,Retinal ,Hydrogen Peroxide ,Oxidants ,Mitochondria ,Oxidative Stress ,030104 developmental biology ,chemistry ,030220 oncology & carcinogenesis ,Retinal Cone Photoreceptor Cells ,Animal studies ,medicine.symptom ,Peptides ,Reactive Oxygen Species ,business ,Oligopeptides - Abstract
Retinopathy is an eye disease caused by the death of retinal cells in the macular area and the surrounding choroid. As the retinal rod cell dysfunction and death lead to the loss of night vision, the disease will lead to visual dysfunction and blindness as the disease progresses. Because of the irreversible nature of cell death, gene therapy has become a research hotspot in the field of retinopathy. But the technology is still in animal studies or clinical trials, and more research is needed to prove its feasibility. In this study, oxidative damage cell model was established and divided into a control group, H2O2 group, SS31 +NEC1 group, SS31 +H2O2 group, and SS31 +NEC1 +H2O2 group, for different interventions. The cell survival rate of the H2O2 group was significantly increased compared with those of the SS31 + H2O2 group, SS31 +NEC1 +H2O2 group, and NEC1 +H2O2 group. Nec1 combined treatment significantly reduced reactive oxygen species (ROS) production compared with that in the H2O2 group. The level of MDA in the SS31 group, Nec-1 group and combined treatment of SS31 +NEC1 group decreased significantly compared with the H2O2 group. The proportion of cells with decreased mitochondrial membrane potential in the H2O2 group significantly increased, and the rate of positivity for propidium iodide (PI) of 661W cells in the H2O2 group and the control group significantly increased. Nine hours after H2O2 treatment of 661W cells, the RIP3 expression level began to increase, and peaked at 24 h. The level of RIP3 in the H2O2 group was significantly increased, while this level was downregulated in the SS31 and NEC1 treatment groups. Therefore, this study suggests that SS31 has a partial protective effect on 661W cells by inhibiting necrosis, which has certain guiding significance for the treatment of retinal diseases.
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- 2021
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45. Synergetic Lipid Extraction with Oxidative Damage Amplifies Cell‐Membrane‐Destructive Stresses and Enables Rapid Sterilization
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Huijuan Liu, Jiuhui Qu, Gong Zhang, Qinghua Ji, and Yu Chen
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Cell Extracts ,Surface Properties ,Microorganism ,Cell ,010402 general chemistry ,medicine.disease_cause ,01 natural sciences ,Catalysis ,Cell membrane ,Escherichia coli ,medicine ,Disulfides ,Phospholipids ,Molybdenum ,chemistry.chemical_classification ,Reactive oxygen species ,biology ,010405 organic chemistry ,Cell Membrane ,Sterilization ,Drug Synergism ,General Chemistry ,Sterilization (microbiology) ,Oxidants ,biology.organism_classification ,Anti-Bacterial Agents ,Nanostructures ,0104 chemical sciences ,Disinfection ,Oxidative Stress ,medicine.anatomical_structure ,Membrane ,chemistry ,Biophysics ,Reactive Oxygen Species ,Bacteria - Abstract
Here, we introduce an innovative "poison arrowhead" approach for disinfection based on a nanosheet bacterial inactivation system that acts synergistically to achieve sterilization rates of >99.99 % (Escherichia coli) over an ultrashort time period (≈0.5 min). The two-dimensional MoS2 "arrowhead" configuration has a sharp edge structure that enables the vigorous extraction of lipids from cell membranes and subsequent membrane disruptions. In the presence of permonosulfate, a strong oxidant, sulfur vacancies containing MoS2 activate the stable molecules, which in turn produce reactive oxygen species (ROS) from edge sites to basal areas. This process not only scavenges some portion of the phospholipids to allow for MoS2 surface refreshment but also directly attacks proteins thereby inflicting further damage to injured cells and amplifying the cell-membrane-destructive stresses toward pathogenic microorganisms. With small amounts of the new material, we successfully disinfected natural water (≈99.93 % inactivation in terms of total bacteria) within 30 s.
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- 2021
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46. Effect of different bleaching techniques on DNA damage biomarkers in serum, saliva, and GCF
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D Sürmelioğlu, Hasan Gündoğar, YH Bağiş, and Seyithan Taysi
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Adult ,Male ,0301 basic medicine ,Saliva ,Ozone ,Adolescent ,genetic structures ,DNA damage ,Health, Toxicology and Mutagenesis ,Toxicology ,Young Adult ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Tooth Bleaching ,Humans ,Tooth Bleaching Agents ,chemistry.chemical_classification ,Reactive oxygen species ,Lasers ,Gingival Crevicular Fluid ,Hydrogen Peroxide ,030206 dentistry ,General Medicine ,Oxidants ,030104 developmental biology ,chemistry ,Biochemistry ,8-Hydroxy-2'-Deoxyguanosine ,Female ,sense organs ,DNA Damage - Abstract
Bleaching agents containing a high concentration of H2O2in the dental market lead to formation of reactive oxygen species, which have genotoxic effects. However, ozone bleaching, one of the most effective oxidants known, stimulates blood circulation and immune response and thus it has strong antimicrobial activity against viruses, bacteria, fungi, and protozoa. For these reasons, one of our hypothesis was ozone bleaching would reduce local and systemic DNA damage in the body. Hence, we aimed to determine the oxidative DNA damage biomarker levels in serum, saliva, and gingival crevicular fluid (GCF) by measuring 8-hydroxy-2′-deoxyguanosine (8-OHdG) after different bleaching methods.Forty-eight volunteers who requested dental bleaching were divided into three treatment groups ( n = 16). Group 1: ozone bleaching with the ozone-releasing machine; Group 2: chemical bleaching with 40% hydrogen peroxide (H2O2) gel; Group 3: 40% H2O2gel activated with the diode laser. Initial and post-operative (immediately after bleaching and two weeks later) color measurements were performed with a spectrophotometer. The color changes were calculated with the CIEDE2000 (Δ E00) formula. 8-OHdG levels in serum, saliva, and GCF samples were determined with ELISA. All three treatments resulted in efficient and statistically similar bleaching. The 8-OHdG levels in the serum and saliva were not affected by all bleaching methods ( p > 0.05), but a temporary increase was observed in the GCF for chemical and laser-assisted groups except the ozone group ( p > 0.05). According to the findings, chemical and laser-assisted bleaching can affect DNA damage locally but not systemically. Bleaching with ozone may eliminate this local DNA damage.
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- 2021
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47. Synthesis of 3-Carbonyl Trisubstituted Furans via Pd-Catalyzed Aerobic Cycloisomerization Reaction: Development and Mechanistic Studies
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Guilherme A. M. Jardim, Attilio Chiavegatti Neto, Isac G. Rosset, Marco A. B. Ferreira, and Amanda Aline Barboza
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010405 organic chemistry ,Chemistry ,Organic Chemistry ,Oxidative phosphorylation ,Oxidants ,010402 general chemistry ,01 natural sciences ,Combinatorial chemistry ,Catalysis ,0104 chemical sciences ,Cycloisomerization ,Molecular oxygen ,Furans ,Oxidation-Reduction ,Palladium - Abstract
Herein, we report the synthesis of 3-carbonyl-trisubstituted furans via Pd-catalyzed oxidative cycloisomerization reactions of 2-alkenyl-1,3-dicarbonyl scaffolds, using molecular oxygen as the sole oxidant to regenerate active palladium catalytic species, featuring good functional tolerance and mild reaction conditions. Deep investigation of intermediates and transition states of the reaction mechanism were conducted via experimental and DFT studies, providing a detailed mechanistical profile. The new developed methodology presents a greener alternative to Wacker-type cycloisomerizations and avoids the use of stoichiometric amounts of oxidants and strong acid additives.
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- 2021
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48. Borate Ameliorates Sodium Nitrite-Induced Oxidative Stress Through Regulation of Oxidant/Antioxidant Status: Involvement of the Nrf2/HO-1 and NF-κB Pathways
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Tarek K. Abouzed, Adil Aldhahrani, Mustafa Shukry, Mohamed Mohamed Soliman, and Samir A. El-Shazly
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Male ,Antioxidant ,NF-E2-Related Factor 2 ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Clinical Biochemistry ,010501 environmental sciences ,Pharmacology ,medicine.disease_cause ,01 natural sciences ,Biochemistry ,Antioxidants ,Inorganic Chemistry ,Lipid peroxidation ,Superoxide dismutase ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,Borates ,medicine ,Animals ,Sodium nitrite ,0105 earth and related environmental sciences ,0303 health sciences ,Sodium Nitrite ,biology ,030302 biochemistry & molecular biology ,Biochemistry (medical) ,NF-kappa B ,General Medicine ,Glutathione ,Oxidants ,Oxidative Stress ,chemistry ,Catalase ,Toxicity ,biology.protein ,Heme Oxygenase-1 ,Oxidative stress - Abstract
The widespread industrial use of nitrite in preservatives, colorants, and manufacturing rubber products and dyes increases the possibilities of organ toxicity. Lithium borate (LB) is known as an antioxidant and an oxidative stress reliever. Therefore, this study is aimed at examining the effect of LB on nitrite-induced hepatorenal dysfunction. Twenty-eight male Swiss mice were divided into four equal groups. Group 1, the control group, received saline. Group 2 received LB orally for 5 consecutive days at a dose of 15 mg/kg bw. Group 3, the nitrite group, received sodium nitrite (NaNO2) on Day 5 (60 mg/kg bw intraperitoneally). Group 4, the protective group (LB + NaNO2 group), received LB for 5 days and then a single dose of NaNO2 intraperitoneally on Day 5, the same as in Groups 2 and 3, respectively. Samples of blood and kidney were taken for serum analysis of hepatorenal biomarkers, levels of antioxidants and cytokines, and the expression of genes associated with oxidative stress and inflammation. NaNO2 intoxication increased markers of liver and kidney functions yet decreased reduced glutathione (GSH), superoxide dismutase (SOD), and catalase activities in blood. NaNO2 also increased the expression of tumor necrosis factor (TNF-α), interleukin-1β and interleukin-6 (IL-1β and IL-6). Pre-administration of LB protected mice from oxidative stress, lipid peroxidation, and the decrease in antioxidant enzyme activity. Moreover, LB protected mice from cytokine changes, which remained within normal levels. LB ameliorated the changes induced by NaNO2 on the mRNA of nuclear factor erythroid 2-related factor 2 (Nfr2), heme oxygenase-1 (HO-1), nuclear factor-kappa B (NF-κB), transforming growth factor-beta 2 (TGF-β2), and glutathione-S-transferase (GST) as determined using quantitative real-time PCR (qRT-PCR). These results collectively demonstrate that LB ameliorated NaNO2-induced oxidative stress by controlling the oxidative stress biomarkers and the oxidant/antioxidant state through the involvement of the Nrf2/HO-1 and NF-κB signaling pathways.
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- 2021
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49. Hydrogen peroxide–induced oxidative stress impairs redox status and damages aerobic metabolism of breast muscle in broilers
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Jiaolong Li, Zuodong Chen, Tong Xing, Yun Jiang, Feng Gao, and Lin Zhang
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Nrf2 signaling pathway ,medicine.medical_specialty ,medicine.medical_treatment ,Intraperitoneal injection ,hydrogen peroxide ,antioxidant capacity ,medicine.disease_cause ,broiler ,Antioxidants ,Pectoralis Muscles ,Metabolism and Nutrition ,Random Allocation ,03 medical and health sciences ,chemistry.chemical_compound ,Internal medicine ,Lactate dehydrogenase ,medicine ,Animals ,030304 developmental biology ,lcsh:SF1-1100 ,chemistry.chemical_classification ,reactive oxygen species ,0303 health sciences ,Chemistry ,Glutathione peroxidase ,0402 animal and dairy science ,Broiler ,04 agricultural and veterinary sciences ,General Medicine ,Metabolism ,Oxidants ,Malondialdehyde ,040201 dairy & animal science ,Oxidative Stress ,Endocrinology ,Dietary Supplements ,glycolysis metabolism ,Animal Science and Zoology ,lcsh:Animal culture ,Chickens ,Oxidation-Reduction ,Anaerobic exercise ,Oxidative stress - Abstract
Oxidative stress has always been a hot topic in poultry science. However, studies concerning the effects of redox status and glucose metabolism induced by hydrogen peroxide (H2O2) in the breast muscle of broilers have been rarely reported. This study was aimed to evaluate the impact of intraperitoneal injection of H2O2 on oxidative damage and glycolysis metabolism of breast muscle in broilers. We also explored the activation of the nuclear factor erythroid 2–related factor 2 (Nrf2) signaling pathway to provide possible mechanism of the redox imbalance. Briefly, a total of 320 one-day-old Arbor Acres chicks were randomly divided into 5 treatments with 8 replicates of 8 birds each (noninjected control, 0.75% saline-injected, 2.5, 5.0, and 10.0% H2O2-injected treatments). Saline group was intraperitoneally injected with physiological saline (0.75%) and H2O2 groups received an intraperitoneal injection of H2O2. The dosage of the injection was 1.0 mL/kg BW. All birds in the saline and H2O2 groups were injected on days 16 and 37 of the experimental period. At 42 d of age, 40 birds (8 cages per group and one chicken per cage) were selected to be stunned electrically (50 V, alternating current, 400 Hz for 5 s each one), and then immediately slaughtered via exsanguination. The results showed that broilers in the H2O2 injection group linearly exhibited higher contents of reactive oxygen species, carbonyl and malondialdehyde, and lower total antioxidant capacity and glutathione peroxidase activities. With the content of H2O2 increased, the H2O2 groups linearly downregulated the mRNA expressions of GPX, CAT, HMOX1, NQO1, and Nrf2 and its downstream target genes. In addition, H2O2 increased serum activities of creatine kinase and lactate dehydrogenase. Meanwhile, in the pectoral muscle, the glycogen content was linearly decreased, and the lactate content was linearly increased in muscle of broilers injected with H2O2. In addition, the activities of glycolytic enzymes including pyruvate kinase, hexokinase, and lactate dehydrogenase were linearly increased after exposure to H2O2. In conclusion, H2O2 injection could impair antioxidant status and enhance anaerobic metabolism of breast muscle in broilers.
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- 2021
50. Lung toxicity and gene expression changes in response to whole-body inhalation exposure to cellulose nanocrystal in rats
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Jenny R. Roberts, Marlene S. Orandle, Tina M. Sager, Christina Umbright, Pius Joseph, Walter McKinney, and Jared L. Cumpston
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Male ,Health, Toxicology and Mutagenesis ,Inflammation ,010501 environmental sciences ,Pharmacology ,Toxicology ,medicine.disease_cause ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Gene expression ,medicine ,Animals ,Cellulose ,Lung ,0105 earth and related environmental sciences ,Inhalation exposure ,Inhalation Exposure ,Lung toxicity ,Body Weight ,Computational Biology ,Lung Injury ,Oxidants ,Rats, Inbred F344 ,Rats ,Gene Expression Regulation ,030228 respiratory system ,chemistry ,Nanocrystal ,Cytokines ,Nanoparticles ,medicine.symptom ,Transcriptome ,Whole body ,Bronchoalveolar Lavage Fluid ,Oxidative stress - Abstract
Human exposure to cellulose nanocrystal (CNC) is possible during the production and/or use of products containing CNC. The objectives of the current study were to determine the lung toxicity of CNC and the underlying molecular mechanisms of the toxicity.Rats were exposed to air or CNC (20 mg/mSignificant increases in lactate dehydrogenase activity, pro-inflammatory cytokine levels, phagocyte oxidant production, and macrophage and neutrophil counts were detected in the bronchoalveolar lavage cells or fluid from the CNC exposed rats. Mild lung histological changes, such as the accumulation of macrophages and neutrophils, were detected in the CNC exposed rats. Gene expression profiling by next generation sequencing identified 531 genes whose expressions were significantly different in the lungs of the CNC exposed rats, compared with the controls. Bioinformatic analysis of the lung gene expression data identified significant enrichment in several biological functions and canonical pathways including those related to inflammation (cellular movement, immune cell trafficking, inflammatory diseases and response, respiratory disease, complement system, acute phase response, leukocyte extravasation signaling, granulocyte and agranulocyte adhesion and diapedesis, IL-10 signaling, and phagosome formation and maturation) and oxidative stress (NRF2-mediated oxidative stress response, production of nitric oxide and reactive oxygen species in macrophages, and free radical scavenging).Our data demonstrated that inhalation exposure of rats to CNC resulted in lung toxicity mediated mainly through the induction of inflammation and oxidative stress.
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- 2021
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