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1.
Environ Sci Technol ; 58(15): 6693-6703, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38577981

RESUMO

A major component of human skin oil is squalene, a highly unsaturated hydrocarbon that protects the skin from atmospheric oxidants. Skin oil, and thus squalene, is continuously replenished on the skin surface. Squalene is also quickly consumed through reactions with ozone and other oxidants. This study examined the extent of squalene depletion in the skin oils of the forearm of human volunteers after exposure to ozone in a climate chamber. Temperature, relative humidity (RH), skin coverage by clothing, and participants' age were varied in a controlled manner. Concentrations of squalene were determined in skin wipe samples collected before and after ozone exposure. Exposures to ozone resulted in statistically significant decreases in post-exposure squalene concentrations compared to pre-exposure squalene concentrations in the skin wipes when squalene concentrations were normalized by concentrations of co-occurring cholesterol but not by co-occurring pyroglutamic acid (PGA). The rate of squalene loss due to ozonolysis was lower than its replenishment on the skin surface. Within the ranges examined, temperature and RH did not significantly affect the difference between normalized squalene levels in post-samples versus pre-samples. Although not statistically significant, skin coverage and age of the volunteers (three young adults, three seniors, and three teenagers) did appear to impact squalene depletion on the skin surfaces.


Assuntos
Poluição do Ar em Ambientes Fechados , Ozônio , Humanos , Adolescente , Esqualeno/análise , Ozônio/análise , Poluição do Ar em Ambientes Fechados/análise , Pele/química , Oxidantes
2.
Environ Sci Technol ; 58(15): 6564-6574, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38578220

RESUMO

Formation of highly oxygenated molecules (HOMs) such as organic peroxides (ROOR, ROOH, and H2O2) is known to degrade food and organic matter. Gas-phase unimolecular autoxidation and bimolecular RO2 + HO2/RO2 reactions are prominently renowned mechanisms associated with the formation of peroxides. However, the reaction pathways and conditions favoring the generation of peroxides in the aqueous phase need to be evaluated. Here, we identified bulk aqueous-phase ROOHs in varying organic precursors, including a laboratory model compound and monoterpene oxidation products. Our results show that formation of ROOHs is suppressed at enhanced oxidant concentrations but exhibits complex trends at elevated precursor concentrations. Furthermore, we observed an exponential increase in the yield of ROOHs when UV light with longer wavelengths was used in the experiment, comparing UVA, UVB, and UVC. Water-soluble organic compounds represent a significant fraction of ambient cloud-water components (up to 500 µM). Thus, the reaction pathways facilitating the formation of HOMs (i.e., ROOHs) during the aqueous-phase oxidation of water-soluble species add to the climate and health burden of atmospheric particulate matter.


Assuntos
Peróxido de Hidrogênio , Peróxidos , Material Particulado/análise , Oxidantes , Água , Aerossóis
3.
Anticancer Agents Med Chem ; 24(3): 224-234, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38629155

RESUMO

BACKGROUND: The side effects of conventional therapeutics pose a problem for cancer treatment. Recently, combination treatments with natural compounds have attracted attention regarding limiting the side effects of treatment. Oleuropein is a natural polyphenol in olives that has antioxidant and anticancer effects. OBJECTIVES: This study aimed to investigate the oxidative stress effect of a combination of Paclitaxel, a chemotherapeutic agent, and Oleuropein in the MCF-7 cell line. METHODS: The xCELLigence RTCA method was used to determine the cytotoxic effects of Oleuropein and Paclitaxel in the MCF-7 cell line. The Total Oxidant and Total Antioxidant Status were analyzed using a kit. The Oxidative Stress Index was calculated by measuring Total Oxidant and Total Antioxidant states. The levels of superoxide dismutase, reduced glutathione and malondialdehyde, which are oxidative stress markers, were also measured by ELISA assay kit. RESULTS: As a result of the measurement, IC50 doses of Oleuropein and Paclitaxel were determined as 230 µM and 7.5 µM, respectively. Different percentages of combination ratios were generated from the obtained IC50 values. The effect of oxidative stress was investigated at the combination rates of 10%, 20%, 30%, and 40% which were determined to be synergistic. In terms of the combined use of Oleuropein and Paclitaxel on oxidative stress, antioxidant defense increased, and Oxidative Stress Index levels decreased. CONCLUSION: These findings demonstrate that the doses administered to the Oleuropein+Paclitaxel combination group were lower than those administered to groups using one agent alone (e.g. Paclitaxel), the results of which reduce the possibility of administering toxic doses.


Assuntos
Neoplasias da Mama , Glucosídeos Iridoides , Paclitaxel , Humanos , Feminino , Paclitaxel/farmacologia , Neoplasias da Mama/tratamento farmacológico , Células MCF-7 , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Iridoides/farmacologia , Estresse Oxidativo , Oxidantes/farmacologia , Oxidantes/uso terapêutico
4.
Environ Monit Assess ; 196(5): 431, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38580863

RESUMO

Effluent containing tartrazine can affect the environment and human health significantly prompting the current study into degradation using a sonochemical reactor operated individually and combined with advanced oxidation processes. The optimum conditions for ultrasound treatment were established as dye concentration of 10 ppm, pH of 3, temperature as 35 °C, and power as 90 W. The combination approach of H2O2/UV, H2O2/US, and H2O2/UV/US resulted in higher degradation of 25.44%, 57.4%, and 74.36% respectively. Use of ZnO/UV/US approach increased the degradation significantly to 85.31% whereas maximum degradation as 93.11% was obtained for the US/UV/Fenton combination. COD reduction was found maximum as 83.78% for the US/UV/Fenton combination. The kinetic analysis showed that tartrazine dye degradation follows pseudo first-order kinetics for all the studied processes. Combination of Fenton with UV and US was elucidated as the best approach for degradation of tartrazine.


Assuntos
Oxidantes , Tartrazina , Humanos , Peróxido de Hidrogênio , Cinética , Ferro , Monitoramento Ambiental , Raios Ultravioleta , Oxirredução
5.
Chemosphere ; 355: 141788, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38548088

RESUMO

N/S co-doping has emerged as a prevailing strategy for carbon-based adsorbents to facilitate the antibiotic removal efficiency. Nevertheless, the underlying interplay among N, S, and their adjacent vacancy defects remains overlooked. Herein, we present a novel in situ strategy for fabricating pyridinic-N dominated and S dual-doped porous carbon adsorbent with rich vacancy defects (VNSC). The experimental results revealed that N (acting as the electron donor) and S (acting as the electron acceptor) form an internal electric field (IEF), with a stronger IEF generated between pyridinic-N and S, while their adjacent vacancy defects activate carbon π electrons, thus enhancing the charge transfer of the IEF. Density functional theory (DFT) calculations further demonstrated that the rich charge transfer in the IEF facilitated the π-π electron donor-acceptor (EDA) interaction between VNSC and tetracycline (TC) as well as norfloxacin (NOR), and thus is the key to adsorption performance of VNSC. Consequently, VNSC exhibited high adsorption capacities toward TC (573.1 mg g-1) and NOR (517.0 mg g-1), and its potential for environmental applications was demonstrated by interference, environmentally relevant concentrations, fixed-bed column, and regeneration tests. This work discloses the natures of adsorption capacity for N/S dual-doped carbon-based materials for antibiotics.


Assuntos
Antibacterianos , Norfloxacino , Porosidade , Tetraciclina , Adsorção , Carbono , Oxidantes
6.
Appl Environ Microbiol ; 90(4): e0204423, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38483171

RESUMO

The ability of some white rot basidiomycetes to remove lignin selectively from wood indicates that low molecular weight oxidants have a role in ligninolysis. These oxidants are likely free radicals generated by fungal peroxidases from compounds in the biodegrading wood. Past work supports a role for manganese peroxidases (MnPs) in the production of ligninolytic oxidants from fungal membrane lipids. However, the fatty acid alkylperoxyl radicals initially formed during this process are not reactive enough to attack the major structures in lignin. Here, we evaluate the hypothesis that the peroxidation of fatty aldehydes might provide a source of more reactive acylperoxyl radicals. We found that Gelatoporia subvermispora produced trans-2-nonenal, trans-2-octenal, and n-hexanal (a likely metabolite of trans-2,4-decadienal) during the incipient decay of aspen wood. Fungal fatty aldehydes supported the in vitro oxidation by MnPs of a nonphenolic lignin model dimer, and also of the monomeric model veratryl alcohol. Experiments with the latter compound showed that the reactions were partially inhibited by oxalate, the chelator that white rot fungi employ to detach Mn3+ from the MnP active site, but nevertheless proceeded at its physiological concentration of 1 mM. The addition of catalase was inhibitory, which suggests that the standard MnP catalytic cycle is involved in the oxidation of aldehydes. MnP oxidized trans-2-nonenal quantitatively to trans-2-nonenoic acid with the consumption of one O2 equivalent. The data suggest that when Mn3+ remains associated with MnP, it can oxidize aldehydes to their acyl radicals, and the latter subsequently add O2 to become ligninolytic acylperoxyl radicals.IMPORTANCEThe biodegradation of lignin by white rot fungi is essential for the natural recycling of plant biomass and has useful applications in lignocellulose bioprocessing. Although fungal peroxidases have a key role in ligninolysis, past work indicates that biodegradation is initiated by smaller, as yet unidentified oxidants that can infiltrate the substrate. Here, we present evidence that the peroxidase-catalyzed oxidation of naturally occurring fungal aldehydes may provide a source of ligninolytic free radical oxidants.


Assuntos
Basidiomycota , Manganês , Polyporales , Lignina/metabolismo , Proteínas Fúngicas/metabolismo , Basidiomycota/metabolismo , Aldeídos , Peroxidases/metabolismo , Ácidos Graxos , Oxidantes
7.
Chemosphere ; 354: 141587, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38494002

RESUMO

Electron transfer played key role in peroxymonosulfate (PMS) activation for heterogeneous Fenton-like catalysts (HFCs). However, the relationship between electron exchange capacity (EEC) and catalytic activity of HFCs has not been elucidated. Herein, thirteen HFCs reported in our previous studies were selected to measure their EEC via electrochemical methods and to investigate the correlation between EEC and catalytic activity for PMS. The results show that nitrogen-doped graphene oxide had much higher EEC (5.299 mM(e) g-1), followed by reduced graphene oxide (3.23 mM(e) g-1), nitrogen-doped biochar-700 (2.032 mM(e) g-1), graphene oxdie (1.789 mM(e) g-1), nitrogen-doped biochar-300 (1.15 mM(e) g-1), g-C3N4 (0.752 mM(e) g-1) and biochar (0.351 mM(e) g-1). For carbon materials, their catalytic activity was not determined by electron donor capacity (EDC), electron acceptor capacity (EAC) and EEC (EDC + EAC), but was linear correlation with |EDC-EAC| that can characterize the extent of HFCs reacting with PMS. The higher the |EDC-EAC| is, the higher the catalytic activity of HFCs is. For carbonaceous materials, their catalytic activity was not proportional to EAC, but had good linear correlation with EDC and |EDC-EAC|. The discrepancy between carbon materials and carbonaceous materials could be due to the different activation mechanisms. Further analysis found that there was no correlation between EEC and the reactive species derived from PMS, indicating that the produced reactive species was not only controlled by EEC. This study firstly elucidated the correlation between EEC and catalytic activity of HFCs, and |EDC-EAC| could be used as an index for evaluating the catalytic activity of HFCs.


Assuntos
Carvão Vegetal , Elétrons , Grafite , Peróxidos , Peróxidos/química , Carbono/química , Oxidantes , Nitrogênio/química
8.
Chemosphere ; 354: 141684, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38494005

RESUMO

The presented research concerns the use of nickel cobaltite nanoparticles (NiCo2O4 NPs) for the heterogeneous activation of peracetic acid and application of NiCo2O4-PAA system for degradation 10 organic micropollutants from the group of bisphenols. The bisphenols removal (initial concentration 1 µM) process was optimized by selecting the appropriate process conditions. The optimal amount of catalyst (115 mg/L), peracetic acid (PAA) concentration (7 mM) and pH (7) were determined using response surface analysis in the Design of Experiment. Then, NiCo2O4 NPs were used to check the possibility of reuse in subsequent oxidation cycles. The work also attempts to explain the mechanism of oxidation of the studied micropollutants. The participation of the sorption process on the catalyst was excluded and based on the experiments with radical scavengers it can be concluded that the oxidation proceeds in a radical pathway, mainly with participation of O2•- radicals. Experiments conducted in real water matrices exhibit low impact on degradation efficiency. Toxicity tests with green alga Acutodesmus obliquus and aquatic plant Lemna minor showed that post-reaction mixture influenced growth and the content of photosynthetic pigments in concentration dependent manner.


Assuntos
Araceae , Compostos Benzidrílicos , Minerais , Oxidantes , Fenóis , Poluentes Químicos da Água , Ácido Peracético , Peróxido de Hidrogênio , Níquel , Oxirredução
9.
J Hazard Mater ; 469: 134004, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38521041

RESUMO

Chronic inflammation induced in vivo by mineral fibres, such as asbestos, is sustained by the cyclic formation of cytotoxic/genotoxic oxidant species that are catalysed by iron. High catalytic activity is observed when iron atoms are isolated in the crystal lattice (nuclearity=1), whereas the catalytic activity is expected to be reduced or null when iron forms clusters of higher nuclearity. This study presents a novel approach for systematically measuring iron nuclearity across a large range of iron-containing standards and mineral fibres of social and economic importance, and for quantitatively assessing the relation between nuclearity and toxicity. The multivariate curve resolution (MCR) empirical approach and density functional theory (DFT) calculations were applied to the analysis of UV-Vis spectra to obtain information on the nature of iron and nuclearity. This approach led to the determination of the nuclearity of selected mineral fibres which was subsequently used to calculate a toxicity-related index. High nuclearity-related toxicity was estimated for chrysotile samples, fibrous glaucophane, asbestos tremolite, and fibrous wollastonite. Intermediate values of toxicity, corresponding to a mean nuclearity of 2, were assigned to actinolite asbestos, amosite, and crocidolite. Finally, a low nuclearity-related toxicity parameter, corresponding to an iron-cluster with a lower catalytic power to produce oxidants, was assigned to asbestos anthophyllite.


Assuntos
Amianto , Ferro , Fibras Minerais/toxicidade , Fibras Minerais/análise , Amianto/toxicidade , Asbestos Serpentinas , Asbesto Crocidolita , Oxidantes
10.
Free Radic Biol Med ; 217: 179-189, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38490457

RESUMO

Redox organization governs an underlying simplicity in living systems. Critically, redox reactions enable the essential characteristics of life: extraction of energy from the environment, use of energy to support metabolic and structural organization, use of dynamic redox responses to defend against environmental threats, and use of redox mechanisms to direct differentiation of cells and organ systems essential for reproduction. These processes are sustained through a redox context in which electron donor/acceptor couples are poised at substantially different steady-state redox potentials, some with relatively reducing steady states and others with relatively oxidizing steady states. Redox-sensitive thiols of the redox proteome, as well as low molecular weight redox-active molecules, are maintained individually by the kinetics of oxidation-reduction within this redox system. Recent research has revealed opposing network interactions of the metallome, redox proteome, metabolome and transcriptome, which appear to be an evolved redox response structure to maintain stability of an organism in the presence of variable oxidative environments. Considerable opportunity exists to improve human health through detailed understanding of these redox networks so that targeted interventions can be developed to support new avenues for redox medicine.


Assuntos
Oxidantes , Proteoma , Humanos , Oxirredução , Compostos de Sulfidrila
11.
Cell Biol Int ; 48(5): 712-725, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38499507

RESUMO

The involvement of the TRP vanilloid 1 (TRPV1) cation channel on the 5-Fluorouracil (5-FU)-caused Ca2+ signals through the activation of the apoptotic signaling pathway and stimulating the mitochondrial Ca2+ and Zn2+ accumulation-induced reactive oxygen species (ROS) productions in several cancer cells, except the colorectal cancer (HT-29) cell line, was recently reported. I aimed to investigate the action of silver nanoparticles (SiNPs) and 5-FU incubations through the activation of TRPV1 on ROS, apoptosis, and cell death in the HT-29 cell line. The cells were divided into four groups: control, SiNP (100 µM for 48 h), 5-FU (25 µM for 24 h), and 5-FU + SiNP. SiNP treatment through TRPV1 activation (via capsaicin) stimulated the oxidant and apoptotic actions of 5-FU in the cells, whereas they were diminished in the cells by the TRPV1 antagonist (capsazepine) treatment. The apoptotic and cell death actions of 5-FU were determined by increasing the propidium iodide/Hoechst rate, caspase-3, -8, and -9 activations, mitochondrial membrane depolarization, lipid peroxidation, and ROS, but decreasing the glutathione and glutathione peroxidase. The increase of cytosolic free Ca2+ and Zn2+ into mitochondria via the stimulation of TRPV1 current density increased oxidant and apoptotic properties of 5-FU in the cells. For the therapy of HT-29 tumor cells, I found that the combination of SiNPs and 5-FU was synergistic via TRPV1 activation.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Nanopartículas Metálicas , Humanos , Espécies Reativas de Oxigênio/metabolismo , Fluoruracila/farmacologia , Estresse Oxidativo , Prata/farmacologia , Sinalização do Cálcio , Regulação para Cima , Antineoplásicos/farmacologia , Apoptose , Oxidantes/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Cálcio/metabolismo , Canais de Cátion TRPV/metabolismo
12.
J Cancer Res Ther ; 20(1): 369-374, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38554348

RESUMO

BACKGROUND: Oxidative stress has a potential role in carcinogenesis. Anti-oxidant enzymes have a neutralizing effect on both cancer initiation and progression. We aimed to assess the oxidant and anti-oxidant levels of pediatric cancer patients and to compare the levels in healthy controls. MATERIALS AND METHODS: The study involved 105 pediatric cancer patients (40 undergoing chemotherapy, 65 survivors) and 40 healthy children. The serum total oxidant status (TOS) and total anti-oxidant status (TAS) were measured. RESULTS: The oxidative stress index was significantly lower in pediatric cancer patients compared to the levels in the controls (0.20 ± 0.07 vs. 0.26 ± 0.10; P = 0.001). The mean serum TAS level was significantly higher in patient groups compared to the level in the control (1.87 ± 0.48 vs. 1.63 ± 0.32 mmol/L, P = 0.001). The TAS level of children with cancer in survivors was also found to be significantly higher compared to the levels in the control group (1.85 ± 0.45 vs. 1.63 ± 0.32 mmol/L, P = 0.005). Radiotherapy, surgery, relapsed disease, presence of metastases, and receiving enteral nutritional support caused no change in the TAS/TOS level. CONCLUSION: It has been revealed for the first time that the serum total anti-oxidant level was high in children undergoing chemotherapy and the survivor group as well. Moreover, the oxidative stress index was low in children with cancer. Longitudinal prospective studies are needed to reveal the alterations in oxidant status among children with cancer.


Assuntos
Antioxidantes , Neoplasias , Criança , Humanos , Antioxidantes/metabolismo , Oxidantes , Estresse Oxidativo , Neoplasias/terapia , Estudos de Casos e Controles
13.
Toxicol Ind Health ; 40(5): 232-243, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38467557

RESUMO

Exposure of zebrafish embryos to glucose is a suitable model for the fetal hyperglycemia seen in gestational diabetes. Diethylhexyl phthalate (DEHP), which is considered an endocrine-disrupting chemical, is one of the most common phthalate derivatives used in stretching plastic and is encountered in every area where plastic is used in daily life. In the present study, the effects of DEHP on pathways related to insulin resistance and obesity were examined in zebrafish embryos exposed to glucose as a fetal hyperglycemia model. Zebrafish embryos were exposed to DEHP, glucose, and glucose + DEHP for 72 h post-fertilization (hpf), and developmental parameters and locomotor activities were monitored. At 72 hpf ins, lepa, pparγ, atf4a, and il-6 expressions were determined by RT-PCR. Glucose, lipid peroxidation (LPO), nitric oxide (NO) levels, glutathione S-transferase (GST), superoxide dismutase (SOD), and acetylcholine esterase (AChE) activities were measured spectrophotometrically. Compared with the control group, glucose, LPO, GST activity, il6, and atf4a expressions increased in all exposure groups, while body length, locomotor, and SOD activities decreased. While AChE activity decreased in the DEHP and glucose groups, it increased in the glucose + DEHP group. Although glucose exposure increased pparγ and lepa expressions, DEHP significantly decreased the expressions of pparγ and lepa both in the DEHP and glucose + DEHP groups. Our findings showed that DEHP amplified oxidant and inflammatory responses in this fetal hyperglycemia model, predisposing insulin resistance in zebrafish embryos.


Assuntos
Dietilexilftalato , Hiperglicemia , Resistência à Insulina , Animais , Dietilexilftalato/toxicidade , Peixe-Zebra/metabolismo , Oxidantes , PPAR gama , Glucose/metabolismo , Hiperglicemia/induzido quimicamente , Superóxido Dismutase
14.
Neurologia (Engl Ed) ; 39(3): 292-301, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38553104

RESUMO

INTRODUCTION: This paper highlights the relationship of inflammation and oxidative stress as damage mechanisms of Multiple Sclerosis (MS), considered an inflammatory and autoimmune disease. DEVELOPMENT: The oxidative stress concept has been defined by an imbalance between oxidants and antioxidants in favor of the oxidants. There is necessary to do physiological functions, like the respiration chain, but in certain conditions, the production of reactive species overpassed the antioxidant systems, which could cause tissue damage. On the other hand, it is well established that inflammation is a complex reaction in the vascularized connective tissue in response to diverse stimuli. However, an unregulated prolonged inflammatory process also can induce tissue damage. CONCLUSION: Both inflammation and oxidative stress are interrelated since one could promote the other, leading to a toxic feedback system, which contributes to the inflammatory and demyelination process in MS.


Assuntos
Esclerose Múltipla , Humanos , Estresse Oxidativo/fisiologia , Inflamação , Antioxidantes/metabolismo , Oxidantes
15.
Scand J Immunol ; 99(1): e13328, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38441277

RESUMO

Calcineurin inhibitors have been found to exhibit a preventive role against neuroinflammation, which represents a crucial underlying mechanism in neurodegenerative diseases (ND). Additionally, they possess suppressive effects on the activation of apoptotic pathways, which constitute another mechanism underlying such diseases. Given that pimecrolimus, a calcineurin inhibitor, impedes the synthesis of pro-inflammatory cytokines, such as interleukin (IL)-2, IL-4, and IL-10, and influences apoptotic processes, it is noteworthy to test its potential neuroprotective properties. Thus, the objective of this investigation was to assess the potential protective effects of pimecrolimus against the degenerative consequences of both microglial secretomes and hydrogen peroxide (H2O2), an oxidant agent. The survival rates of HMC3 microglia cells, neuron-like differentiated SH-SY5Y (d-SH-SY5Y) cells, and their co-culture were determined using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) method. Furthermore, the levels of pro-inflammatory cytokines IL-1ß and IL-6, and anti-inflammatory cytokine IL-10 were measured using ELISA kits, besides total antioxidant and oxidant capacities in conditioned media of cells. Additionally, the effect of pimecrolimus on neurite length in these cell groups was evaluated through morphological observations. This study revealed, for the first time, that pimecrolimus exerts preventive effects on neurodegenerative processes by virtue of its anti-inflammatory and -antioxidant activities. It holds promise as a potential treatment option for ND.


Assuntos
Antioxidantes , Neuroblastoma , Tacrolimo/análogos & derivados , Humanos , Antioxidantes/farmacologia , Peróxido de Hidrogênio , Interleucina-10 , Microglia , Secretoma , Neurônios , Oxidantes , Citocinas , Anti-Inflamatórios/farmacologia
16.
Chemosphere ; 355: 141766, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38527631

RESUMO

Azo dyes are largely used in many industries and discharged in large volumes of their effluents into the aquatic environment giving rise to non-esthetic pollution and health-risk problems. Due to the high stability of azo dyes in ambient conditions, they cannot be abated in conventional wastewater treatment plants. Over the last fifteen years, the decontamination of dyeing effluents by persulfate (PS)-based advanced oxidation processes (AOPs) has received a great attention. In these methods, PS is activated to be decomposed into sulfate radical anion (SO4•-), which is further partially hydrolyzed to hydroxyl radical (•OH). Superoxide ion (O2•-) and singlet oxygen (1O2) can also be produced as oxidants. This review summarizes the results reported for the discoloration and mineralization of synthetic and real waters contaminated with azo dyes covering up to November 2023. PS activation with iron, non-iron transition metals, and carbonaceous materials catalysts, heat, UVC light, photocatalysis, photodegradation with iron, electrochemical and related processes, microwaves, ozonation, ultrasounds, and other processes is detailed and analyzed. The principles and characteristics of each method are explained with special attention to the operating variables, the different oxidizing species generated yielding radical and non-radical mechanisms, the addition of inorganic anions and natural organic matter, the aqueous matrix, and the by-products identified. Finally, the overall loss of toxicity or partial detoxification of treated azo dye solutions during the PS-based AOPs is discussed.


Assuntos
Compostos Azo , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Ferro , Oxirredução , Oxidantes , Água
17.
mSystems ; 9(4): e0116523, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38530056

RESUMO

To establish infections in human hosts, Pseudomonas aeruginosa must overcome innate immune-generated oxidative stress, such as the hypochlorous acid (HOCl) produced by neutrophils. We set out to find specific biomarkers of oxidative stress through the development of a protocol for the metabolic profiling of P. aeruginosa cultures grown in the presence of different oxidants using a novel ionization technique for mass spectrometry, laser desorption rapid evaporative ionization mass spectrometry (LD-REIMS). We demonstrated the ability of LD-REIMS to classify samples as untreated or treated with a specific oxidant with 100% accuracy and identified a panel of 54 metabolites with significantly altered concentrations after exposure to one or more of the oxidants. Key metabolic changes were conserved in P. aeruginosa clinical strains isolated from patients with cystic fibrosis lung infections. These data demonstrated that HOCl stress impacted the Pseudomonas quinolone signal (PQS) quorum sensing system. Ten 2-alkyl-4-quinolones (AHQs) associated with the PQS system were significantly lower in concentration in HOCl-stressed P. aeruginosa cultures, including 2-heptyl-3-hydroxy-4(1H)-quinolone (PQS), the most active signal molecule of the PQS system. The PQS system regulates the production of virulence factors, including pyocyanin and elastase, and their levels were markedly affected by HOCl stress. No pyocyanin was detectable and elastase concentrations were reduced by more than 75% in cultures grown with sub-lethal concentrations of HOCl, suggesting that this neutrophil-derived oxidant may disrupt the ability of P. aeruginosa to establish infections through interference with production of PQS-associated virulence factors. IMPORTANCE: This work demonstrates that a high-throughput ambient ionization mass spectrometry method can be used successfully to study a bacterial stress response. Its application to the opportunistic pathogen Pseudomonas aeruginosa led to the identification of specific oxidative stress biomarkers, and demonstrated that hypochlorous acid, an oxidant specifically produced by human neutrophils during infection, affects quorum sensing and reduces production of the virulence factors pyocyanin and elastase. No pyocyanin was detectable and elastase levels were reduced by more than 75% in bacteria grown in the presence of hypochlorous acid. This approach has the potential to be widely applicable to the characterization of the stress responses of bacteria.


Assuntos
Quinolonas , Percepção de Quorum , Humanos , Pseudomonas aeruginosa , Ácido Hipocloroso/metabolismo , Piocianina/metabolismo , Quinolonas/análise , Fatores de Virulência/metabolismo , Espectrometria de Massas , Oxidantes/metabolismo , Elastase Pancreática/metabolismo , Biomarcadores/metabolismo , Lasers
18.
Biorheology ; 59(3-4): 81-96, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38461496

RESUMO

BACKGROUND: A challenge for coaches and athletes is to find the best combination of exercises during training. Considering its favorable effects, HIIT has been very popular recently. OBJECTIVE: The goal of this study was to investigate anthropometric features, performance, erythrocyte deformability, plasma viscosity (PV) and oxidative stress in response to acute and long-term (6 weeks) HIIT in adolescent basketball players. METHODS: 22 sportsmen between the ages of 14-16 were included. Tabata protocol was applied to the HIIT group in addition to their routine training program 3 days/week, for 6 weeks. Erythrocyte deformability was determined using an ectacytometer (LORCA), PV with a rotational viscometer. Total oxidant status (TOS), total antioxidant status (TAS) were measured by kits. RESULTS: HIIT for 6 weeks induced an improvement in performance tests and waist circumference. 6 weeks of HIIT resulted in a decrement, while the last exercise session yielded an increment in RBC deformability. PV and TOS of HIIT groups were decreased on the 6th week. CONCLUSIONS: Our results demonstrate that, HIIT in addition to the routine exercise program is beneficial for improving performance and blood fluidity as well as decreasing oxidative stress in basketball players. Therefore, HIIT seems as an efficient training strategy for highly-trained individuals.


Assuntos
Basquetebol , Adolescente , Humanos , Basquetebol/fisiologia , Estresse Oxidativo , Antioxidantes/metabolismo , Exercício Físico/fisiologia , Deformação Eritrocítica/fisiologia , Oxidantes
19.
Environ Sci Technol ; 58(11): 5139-5152, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38446791

RESUMO

Plasma has been proposed as an alternative strategy to treat organic contaminants in brines. Chemical degradation in these systems is expected to be partially driven by halogen oxidants, which have been detected in halide-containing solutions exposed to plasma. In this study, we characterized specific mechanisms involving the formation and reactions of halogen oxidants during plasma treatment. We first demonstrated that addition of halides accelerated the degradation of a probe compound known to react quickly with halogen oxidants (i.e., para-hydroxybenzoate) but did not affect the degradation of a less reactive probe compound (i.e., benzoate). This effect was attributed to the degradation of para-hydroxybenzoate by hypohalous acids, which were produced via a mechanism involving halogen radicals as intermediates. We applied this mechanistic insight to investigate the impact of constituents in brines on reactions driven by halogen oxidants during plasma treatment. Bromide, which is expected to occur alongside chloride in brines, was required to enable halogen oxidant formation, consistent with the generation of halogen radicals from the oxidation of halides by hydroxyl radical. Other constituents typically present in brines (i.e., carbonates, organic matter) slowed the degradation of organic compounds, consistent with their ability to scavenge species involved during plasma treatment.


Assuntos
Oxidantes , Sais , Poluentes Químicos da Água , Compostos Orgânicos , Radical Hidroxila/química , Oxirredução , Halogênios/química , Hidroxibenzoatos , Poluentes Químicos da Água/química
20.
PLoS One ; 19(3): e0285515, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38446761

RESUMO

Micro- and nanoplastics are widespread throughout the world. In particular, polyethylene (PE) and polyethylene terephthalate or polyester (PET) are two of the most common polymers, used as plastic bags and textiles. To analyze the toxicity of these two polymers, oligomers with different numbers of units were used as models. The use of oligomers as polymeric templates has been used previously with success. We started with the monomer and continued with different oligomers until the chain length was greater than two nm. According to the results of quantum chemistry, PET is a better oxidant than PE, since it is a better electron acceptor. Additionally, PET has negatively charged oxygen atoms and can promote stronger interactions than PE with other molecules. We found that PET forms stable complexes and can dissociate the guanine-cytosine nucleobase pair. This could affect DNA replication. These preliminary theoretical results may help elucidate the potential harm of micro- and nanoplastics.


Assuntos
Microplásticos , Polietileno , Polietileno/toxicidade , Microplásticos/toxicidade , Plásticos/toxicidade , Polietilenotereftalatos/toxicidade , Polímeros , Oxidantes
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