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1.
Proc Natl Acad Sci U S A ; 117(4): 1860-1866, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31932452

RESUMO

Oceanic emissions of iodine destroy ozone, modify oxidative capacity, and can form new particles in the troposphere. However, the impact of iodine in the stratosphere is highly uncertain due to the lack of previous quantitative measurements. Here, we report quantitative measurements of iodine monoxide radicals and particulate iodine (Iy,part) from aircraft in the stratosphere. These measurements support that 0.77 ± 0.10 parts per trillion by volume (pptv) total inorganic iodine (Iy) is injected to the stratosphere. These high Iy amounts are indicative of active iodine recycling on ice in the upper troposphere (UT), support the upper end of recent Iy estimates (0 to 0.8 pptv) by the World Meteorological Organization, and are incompatible with zero stratospheric iodine injection. Gas-phase iodine (Iy,gas) in the UT (0.67 ± 0.09 pptv) converts to Iy,part sharply near the tropopause. In the stratosphere, IO radicals remain detectable (0.06 ± 0.03 pptv), indicating persistent Iy,part recycling back to Iy,gas as a result of active multiphase chemistry. At the observed levels, iodine is responsible for 32% of the halogen-induced ozone loss (bromine 40%, chlorine 28%), due primarily to previously unconsidered heterogeneous chemistry. Anthropogenic (pollution) ozone has increased iodine emissions since preindustrial times (ca. factor of 3 since 1950) and could be partly responsible for the continued decrease of ozone in the lower stratosphere. Increasing iodine emissions have implications for ozone radiative forcing and possibly new particle formation near the tropopause.


Assuntos
Poluentes Atmosféricos/análise , Atmosfera/química , Radicais Livres/química , Iodo/análise , Ozônio/análise , Movimentos do Ar , Aeronaves , Radicais Livres/análise , Humanos
2.
Acta Cir Bras ; 34(10): e201901002, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31826148

RESUMO

PURPOSE: To evaluate the effect of garlic on formation of postoperative adhesions in rats. METHODS: Twenty-four Sprague dawley rats were divided into three groups. In Group 1 (sham), laparotomy was performed and stitched up. In Group 2 (control), after laparotomy was performed, punctate hemorrhage was induced by cecal abrasion in the cecum and 2 cc of saline was intraperitoneally administered to each rat. In Group 3 (experimental), after laparotomy was performed, punctate hemorrhage was induced by cecal abrasion in the cecum and each rat was intraperitoneally administered a sterile Allium sativum derivative. The rats in all groups were re-laparotomized on postoperative day 7; samples were obtained from the peritoneal tissue surrounding the cecum. RESULTS: In Group 3, there was a statistically significant difference in terms of inflammation, lymph node size, and free oxygen radicals; these parameters tended to increase. In terms of fibrosis evaluated using H&E and MT, there was no significant difference between groups 2 and 3. CONCLUSIONS: No positive outcomes indicating that Allium sativum reduces intra-abdominal adhesions were obtained. However, it caused severe inflammation in the tissue. Additionally, in immunohistochemical analyses conducted to detect oxidative stress, allium sativum increased the production of free oxygen radicals in the tissue.


Assuntos
Alho/química , Doenças Peritoneais/prevenção & controle , Animais , Fibrose , Radicais Livres/análise , Imuno-Histoquímica , Laparotomia , Linfonodos/efeitos dos fármacos , Linfonodos/patologia , Estresse Oxidativo/efeitos dos fármacos , Doenças Peritoneais/patologia , Complicações Pós-Operatórias/patologia , Complicações Pós-Operatórias/prevenção & controle , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Aderências Teciduais/patologia , Aderências Teciduais/prevenção & controle
3.
Int J Med Mushrooms ; 21(6): 561-570, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679228

RESUMO

The in vitro antioxidant effects of petroleum ether, ethyl acetate, and ethanol extracts isolated from Hericium coralloides were investigated. Overall, the ethyl acetate extract of H. coralloides (HcEAE) showed better antioxidant activity in vitro than the petroleum ether and ethanol extracts (HcPEE and HcETE, respectively) of H. coralloides. A comprehensive investigation of the antioxidant activity of the HcEAE in vitro indicated that it possessed superior antioxidant activity, with half maximal inhibitory concentration (IC50) values of 0.93, 1.84, 1.59, and 0.6 mg/mL against DPPH, hydroxyl, ABTS+, and superoxide (O2- ) radicals, respectively. To assess in vivo antioxidant activity, three different doses of HcEAE were orally administered in a D-galactose-induced aged mouse model. Administration of HcEAE significantly increased the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) and lowered the levels of malondialdehyde (MDA) in brains and sera of mice in a dose-dependent manner. A histopathology assessment indicated that the HcEAE could ameliorate the anile condition of the model mice. These results suggest that the HcEAE has potent antioxidant activity and could minimize the occurrence of age-associated disorders associated with free radicals.


Assuntos
Agaricales/química , Envelhecimento , Antioxidantes/análise , Extratos Celulares/farmacologia , Acetatos/análise , Envelhecimento/efeitos dos fármacos , Alcanos/análise , Animais , Catalase/análise , Extratos Celulares/química , Etanol , Radicais Livres/análise , Concentração Inibidora 50 , Masculino , Camundongos , Superóxido Dismutase/análise
4.
Acta cir. bras ; 34(10): e201901002, Oct. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1054669

RESUMO

Abstract Purpose: To evaluate the effect of garlic on formation of postoperative adhesions in rats. Methods: Twenty-four Sprague dawley rats were divided into three groups. In Group 1 (sham), laparotomy was performed and stitched up. In Group 2 (control), after laparotomy was performed, punctate hemorrhage was induced by cecal abrasion in the cecum and 2 cc of saline was intraperitoneally administered to each rat. In Group 3 (experimental), after laparotomy was performed, punctate hemorrhage was induced by cecal abrasion in the cecum and each rat was intraperitoneally administered a sterile Allium sativum derivative. The rats in all groups were re-laparotomized on postoperative day 7; samples were obtained from the peritoneal tissue surrounding the cecum Results: In Group 3, there was a statistically significant difference in terms of inflammation, lymph node size, and free oxygen radicals; these parameters tended to increase. In terms of fibrosis evaluated using H&E and MT, there was no significant difference between groups 2 and 3. Conclusions: No positive outcomes indicating that Allium sativum reduces intra-abdominal adhesions were obtained. However, it caused severe inflammation in the tissue. Additionally, in immunohistochemical analyses conducted to detect oxidative stress, allium sativum increased the production of free oxygen radicals in the tissue.


Assuntos
Animais , Doenças Peritoneais/prevenção & controle , Alho/química , Doenças Peritoneais/patologia , Complicações Pós-Operatórias/patologia , Complicações Pós-Operatórias/prevenção & controle , Fibrose , Imuno-Histoquímica , Aderências Teciduais/patologia , Aderências Teciduais/prevenção & controle , Reprodutibilidade dos Testes , Ratos Sprague-Dawley , Estresse Oxidativo/efeitos dos fármacos , Radicais Livres/análise , Laparotomia , Linfonodos/efeitos dos fármacos , Linfonodos/patologia
5.
Environ Sci Pollut Res Int ; 26(28): 29234-29245, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31396866

RESUMO

To conduct a comprehensive ecological analysis on the solid residues derived from the thermal disposal of hyperaccumulator Pteris vittata, this study focused on the behaviors of As and Pb and the characteristics of environmentally persistent free radicals (EPFRs) in the solid residues under different thermal treatment conditions. The analysis results revealed that the concentrations of As in the biochars and bio-slag were approximately 350 and 1100 mg/kg, respectively. Moreover, the concentrations of Pb in the solid residues varied from 34 to 1050 mg/kg. According to the results of the modified BCR sequential extractions, As is more stable in the biochar while Pb is more stable in the combustion slags. In addition, As showed a higher volatilization temperature compared with Pb. The ecological risk assessment indicated that the correlation index between the contamination factor (Cf) of As and the risk index (R2 = 0.995) is considerably larger than the correlation index between the contamination factor of Pb and the risk index (R2 = 0.117), which implies that the pyrolysis method should be selected at priority. Moreover, the EPFR concentrations of the biochar declined by approximately 75 times when the pyrolysis temperature increased from 500 to 600 °C. This behavior indicated that high-temperature pyrolysis (> 600 °C) could simultaneously control both the heavy metal behavior and EPFR concentrations.


Assuntos
Carvão Vegetal/química , Radicais Livres/química , Metais Pesados/análise , Pteris/química , Gerenciamento de Resíduos/métodos , Arsênico/análise , Arsênico/química , Biodegradação Ambiental , Radicais Livres/análise , Chumbo/análise , Chumbo/química , Metais Pesados/química , Pirólise , Fatores de Risco , Poluentes do Solo/análise , Temperatura , Termogravimetria , Volatilização
6.
Sci Total Environ ; 689: 193-202, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31271986

RESUMO

Environmentally persistent free radicals (EPFRs) have recently attracted considerable attention as a new type of environmental risk substance due to their potential health effects. However, the sources and contributions of EPFRs in PM2.5 are not yet clear. Therefore, this study reports the sources of EPFRs in PM2.5 based on chemical analysis and positive matrix factorization (PMF). Daily PM2.5 samples (116) were collected in Xi'an city from April 4 to December 29, 2017, and were quantitatively analyzed for EPFRs and other chemical constituents. The PMF model revealed contributions from five main sources of EPFRs in PM2.5 (dust sources, coal combustion, secondary nitrates, industrial emissions and motor vehicle emissions). Coal combustion, motor vehicle emissions and dust sources are the top three contributors to EPFRs (76.12% in total). Coal combustion is highly important for PM2.5 (35.10%) and EPFRs (16.75%). A high dust source contribution to EPFRs in spring may be due to dust storm events. Motor vehicle emissions are the top contributor to EPFRs, with a mean percentage of 32.13%. Secondary nitrates barely contributes to EPFRs (3.42%), indicating an EPFR origin from primary emissions rather than secondary inorganic reactions. Industrial emissions contribute less to PM2.5 (4.31%) than to EPFRs (11.71%), which implies that fossil fuels contains many high-molecular-weight organics that could emit EPFRs. Integrating the PMF results with meteorological data revealed that atmospheric pollutants emitted in Xi'an city center could be transported to the sampling site by southern winds. These results suggest the need for further studies on the public health effects of EPFRs and can be used to help formulate source control measures to reduce the potential health risks posed by EPFRs in PM2.5.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Radicais Livres/análise , Material Particulado/análise , Poluentes Atmosféricos/classificação , China
7.
Biomed Chromatogr ; 33(10): e4624, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31215046

RESUMO

Cimicifugae Rhizoma (sheng ma) is a well-known traditional Chinese medicine, which has been demonstrated to possess anti-inflammatory, antipyretic and analgesic activities. In the present study, a simple and efficient HPLC-DAD (high-performance liquid chromatography coupled with diode array detection) method was developed and validated for simultaneous quantification of 19 chemical components (including 16 phenolic acids, one coumarin and two alkaloids) in Cimicifugae Rhizoma. The result indicated that this method could effectively evaluate the quality of Cimicifugae Rhizoma and provide a valuable reference for further study. Additionally, the antioxidant activity of Cimicifugae Rhizoma was evaluated by DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging assay. The results showed that the content of phenolic acids and antioxidant activity exhibited significant correlation coefficients.


Assuntos
Antioxidantes , Cromatografia Líquida de Alta Pressão/métodos , Cimicifuga/química , Medicamentos de Ervas Chinesas , Alcaloides/análise , Alcaloides/isolamento & purificação , Alcaloides/metabolismo , Antioxidantes/análise , Antioxidantes/isolamento & purificação , Antioxidantes/metabolismo , Compostos de Bifenilo/metabolismo , Cumarínicos/análise , Cumarínicos/isolamento & purificação , Cumarínicos/metabolismo , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Radicais Livres/análise , Radicais Livres/isolamento & purificação , Radicais Livres/metabolismo , Hidroxibenzoatos/análise , Hidroxibenzoatos/isolamento & purificação , Hidroxibenzoatos/metabolismo , Limite de Detecção , Modelos Lineares , Picratos/metabolismo , Reprodutibilidade dos Testes
8.
J Pharm Biomed Anal ; 174: 406-413, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31212141

RESUMO

Ethnobotanical evidences substantiate the use of several Centaurea species to treat and/or manage several human ailments. In the present study, the phytochemical profile of the ethyl acetate, methanol, and aqueous extracts (prepared by infusion and decoction) of Centaurea bornmuelleri Hausskn. aerial parts was established. The enzyme inhibitory and antioxidant properties were also determined by in vitro bioassays. Methanol extract (38.58 mg gallic acid equivalent/g extract) and ethyl acetate extract (38.83 mg rutin equivalent/g extract) possessed the highest concentration of phenolics and flavonoids, respectively. Aqueous extract prepared following traditional infusion method showed potent DPPH (38.54 mg TE/g extract) and ABTS (57.75 mg TE/g extract) scavenging abilities. The methanol extract (101.46 mg TE/g extract) of C. bornmuelleri exhibited potent reducing activity in the CUPRAC assay while the aqueous extract obtained by infusion was more active in the FRAP assay (69.81 mg TE/g extract). Ethyl acetate extract of C. bornmuelleri inhibited both acetylcholinesterase (1.14 mg galantamine equivalent [GALAE]/g extract), butyrylcholinesterase (0.63 mg GALAE/g extract), tyrosinase (69.84 mg kojic acid equivalent/g extract), amylase (19.90 mg acarbose equivalent [ACAE]/g extract), and glucosidase (33.12 mg ACAE/g extract). The phytochemical profile of C. bornmuelleri has been characterized and the main components quantified in order to provide scientific base to design innovative products including pharmaceuticals, cosmetics or nutraceuticals although further investigation concerning the isolation of the main bioactive compounds would be required.


Assuntos
Centaurea/química , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Antioxidantes/análise , Butirilcolinesterase/análise , Inibidores da Colinesterase/farmacologia , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Radicais Livres/análise , Metanol/análise , Análise Multivariada , Fenol/análise , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
9.
Food Chem ; 297: 124951, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253340

RESUMO

The shelf lives of hot-air-dried (HD) and freeze-dried (FD) Penaeus vannamei were predicted by accelerated storage testing combined with Arrhenius Equation. Meanwhile, the changes in lipid profiles and colour of the dried shrimps during storage were investigated. The predicted shelf life of FD shrimp was more than 1.47-fold than that of HD shrimp. Compared to HD shrimp, FD shrimp had lower levels of oxidation parameters such as peroxide value (POV) and thiobarbituric acid-reactive substances value (TBARS) during storage. In addition, FD shrimp had less reduction in lipid components such as triacylglycerol (TAG), phosphatidylcholine (PC), phosphatidylethanolamine (PE) and all fatty acids including saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) after storage. Moreover, FD shrimp showed a less significant decrease in redness value and increase in yellowness value. Therefore, FD shrimps have better quality stability during storage and then possess longer shelf life than HD shrimp.


Assuntos
Armazenamento de Alimentos/métodos , Lipídeos/química , Penaeidae/química , Frutos do Mar/análise , Animais , Cor , Ácidos Graxos/análise , Ácidos Graxos/química , Manipulação de Alimentos/métodos , Radicais Livres/análise , Radicais Livres/química , Liofilização , Lipídeos/análise , Valor Nutritivo , Oxirredução , Fosfatidilcolinas/análise , Fosfatidilcolinas/química , Triglicerídeos/análise , Triglicerídeos/química , Xantofilas/análise
10.
Curr Med Chem ; 26(29): 5456-5500, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30621554

RESUMO

This review article is an attempt to summarize the current state of knowledge of the impact of Vanadium (V) on Oxidative Stress (OS) markers in vivo. It shows the results of our studies and studies conducted by other researchers on the influence of different V compounds on the level of selected Reactive Oxygen Species (ROS)/Free Radicals (FRs), markers of Lipid peroxidation (LPO), as well as enzymatic and non-enzymatic antioxidants. It also presents the impact of ROS/peroxides on the activity of antioxidant enzymes modulated by V and illustrates the mechanisms of the inactivation thereof caused by this metal and reactive oxygen metabolites. It also focuses on the mechanisms of interaction of V with some nonenzymatic compounds of the antioxidative system. Furthermore, we review the routes of generation of oxygen-derived FRs and non-radical oxygen derivatives (in which V is involved) as well as the consequences of FR-mediated LPO (induced by this metal) together with the negative/ positive effects of LPO products. A brief description of the localization and function of some antioxidant enzymes and low-molecular-weight antioxidants, which are able to form complexes with V and play a crucial role in the metabolism of this element, is presented as well. The report also shows the OS historical background and OS markers (determined in animals under V treatment) on a timeline, collects data on interactions of V with one of the elements with antioxidant potential, and highlights the necessity and desirability of conducting studies of mutual interactions between V and antioxidant elements.


Assuntos
Biomarcadores/análise , Estresse Oxidativo/efeitos dos fármacos , Vanádio/farmacologia , Animais , Antioxidantes , Biomarcadores/metabolismo , Radicais Livres/análise , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Vanádio/química
11.
Environ Pollut ; 247: 18-26, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30650344

RESUMO

Environmentally persistent free radicals (EPFRs) are a new class of environmental risk substances that can stably exist in atmospheric particles and pose a potential threat to human health. In this study, electron paramagnetic resonance (EPR) spectroscopy was used to study the concentration levels, species characteristics, and sources of EPFRs in PM2.5 in Xi'an in 2017. The results showed that the concentrations of EPFRs in PM2.5 in Xi'an in 2017 ranged from 9.8 × 1011 to 6.9 × 1014 spins/m3. The highest concentration of EPFRs occurred in winter when the average concentration was 2.1 × 1014 spins/m3. The lowest concentration of EPFRs occurred in autumn when the average concentration was 7.0 × 1013 spins/m3. According to the annual average atmospheric concentration of EPFRs, the amount of EPFRs inhaled by people in Xi'an is equivalent to approximately 5 cigarettes per person per day and approximately 23 cigarettes per person per day in winter when haze occurs. The results of the study on the EPFR characteristics show that the EPFRs in PM2.5 in Xi'an are mainly C-center organic radicals that are primarily non-decaying types, accounting for approximately 75% and 85% of total concentration of EPFRs in autumn and winter, respectively. Finally, a correlation analysis was used to explore the origins of EPFRs in PM2.5. Significant positive correlations were found between EPFRs and SO2, NO2 and the thermally derived OC3 and OC4 carbonaceous components. The results suggested that coal-fired and traffic may be important sources of EPFRs in PM2.5 in Xi'an. In addition, EPFRs are significantly positively correlated with O3 in summer, suggesting that some EPFRs may also originate from secondary processes. This study provides important basic data and evidence for further assessments of the potential health risks of EPFRs in PM2.5 and the development of effective air pollution control measures.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Radicais Livres/análise , Material Particulado/análise , China , Carvão Mineral/análise , Humanos , Estações do Ano
12.
Anal Sci ; 35(3): 265-269, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30369554

RESUMO

Basal cell carcinoma (BCC) in paraffin-embedded specimens was investigated by nondestructively electron paramagnetic resonance (EPR) and X-band (9.45 GHz) EPR imaging (EPRI). A histopathological examination of specimens showed the melanin contents and revealed that they were predominantly of the nodular types. A single-line EPR pattern was observed in the BCC specimens, and the spectra of the samples were analyzed using linewidth and spectral pattern parameters. The eumelanin-related radical was observed in paraffin-embedded BCC specimens. The stability of the radical was supported by sepia pigment experiments. The g-value and peak-to-peak linewidths (ΔHpp) were 2.0046 and 0.61 ± 0.02 mT (mean ± SEM), respectively. Strong EPRI signals correspond to areas of strong pigmentation in the samples. Thus, histopathological examination, EPR, and EPRI of BCC specimens showed that the radical distribution reflects on the spatial distribution of pigments in the samples.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres/análise , Melaninas/análise , Neoplasia de Células Basais/patologia , Inclusão em Parafina , Neoplasias Cutâneas/patologia , Idoso , Feminino , Radicais Livres/metabolismo , Humanos , Masculino , Melaninas/metabolismo , Imagem Molecular , Neoplasia de Células Basais/metabolismo , Neoplasias Cutâneas/metabolismo
13.
Chem Res Toxicol ; 32(1): 130-138, 2019 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-30525517

RESUMO

E-cigarettes (e-cigs) are a diverse and continuously evolving group of products with four generations currently in the market. The National Institute on Drug Abuse (NIDA) standardized research e-cigarette (SREC) is intended to provide researchers with a consistent e-cig device with known characteristics. Thus, we conducted laboratory-based characterizations of oxidants and nicotine in aerosols produced from SREC and other closed-system, breath-activated, commercially available e-cigs (Blu and Vuse). We hypothesized that oxidant and nicotine production will be significantly affected in all devices by changes in puffing parameters. All e-cigs were machine vaped and the aerosols generated were examined for nicotine, carbonyls, and free-radicals while varying the puff-volumes and puff-durations to reflect typical human usage. The data were normalized on a per puff, per gram aerosol, and per milligram nicotine basis. We found that aerosol production generally increased with increasing puff-duration and puff-volume in all e-cigs tested. Increased puff-duration and puff-volume increased nicotine delivery for Blu and Vuse but not the SREC. We report, for the first time, reactive free-radicals in aerosols from all closed-system e-cigs tested, albeit at levels lower than cigarette smoke. Formaldehyde, acetaldehyde, acetone, and propionaldehyde were detected in the aerosols of all tested e-cigs. Carbonyl and free radical production is affected by puff-duration and puff volume. Overall, SREC was more efficient at aerosol and nicotine production than both Blu and Vuse. In terms of carbonyl and free radical levels, SREC delivered lower or similar levels to both other devices.


Assuntos
Acetaldeído/análise , Acetona/análise , Acroleína/análise , Sistemas Eletrônicos de Liberação de Nicotina/normas , Formaldeído/análise , National Institute on Drug Abuse (U.S.)/legislação & jurisprudência , Nicotina/análise , Produtos do Tabaco/normas , Aerossóis/análise , Radicais Livres/análise , Humanos , Estados Unidos
14.
Ecotoxicol Environ Saf ; 169: 623-630, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30496994

RESUMO

Environmentally persistent free radicals (EPFRs) in atmospheric fine particulate matters (PM2.5) possess high bioactivity and result in severe health problems. The facile transformation of aromatic pollutants into EPFRs on montmorillonite (MMT), an important solid component in PM2.5, is an activation of air pollutants into more toxic chemical species and also attributes to the secondary source of EPFRs in PM2.5. In this study, the interfacial reactions of pentachlorophenol (PCP), a typical EPFR precursor in air pollution, on the Fe(III)-, Ca- and Na-MMT surfaces have been explored by the density functional theory (DFT) calculations using the periodic slab models. The PCP molecule is found to be exothermically adsorbed on the three MMT surfaces. Moreover, significant charge transfer from PCP to Fe takes place and finally leads to the surface-bound phenoxyl radical formation on the Fe(III)-MMT surface since the half-filled 3d orbital of Fe3+ in Fe(III)-MMT could act as electron acceptor allowing the electron transferring from the 2p orbital of the phenolic O in PCP to Fe ion. However, similar charge transfer is not found in the Ca- and Na-MMTs, and the PCP transformation reaction is hindered on the Ca- and Na-MMT surfaces. Namely, the PCP activation to the corresponding EPFRs is impossible on the Ca-MMT and Na-MMT surfaces, while the catalytically active Fe(III)-MMT in PM2.5 can transform the chlorinated phenols into more toxic phenoxy-type EPFRs at ambient temperatures. Accordingly, more attention should be paid on the effect of MMT with catalytical capacity on the toxicity of PM2.5.


Assuntos
Poluentes Atmosféricos/análise , Bentonita/química , Compostos Férricos/química , Radicais Livres/análise , Material Particulado/química , Pentaclorofenol/análise , Adsorção , Oxirredução , Tamanho da Partícula , Propriedades de Superfície
15.
Free Radic Biol Med ; 131: 299-308, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30576782

RESUMO

Sun radiation is indispensable to our health, however, a long term and high exposure could lead to erythema, premature skin aging and promotion of skin tumors. An underlying pathomechanism is the formation of free radicals. First, reactive oxygen species (*OH, *O2-) and then, secondary lipid oxygen species (C centered radicals, CCR) are formed. A high amount of free radicals results in oxidative stress with subsequent cell damage. In dermatological research different skin models are used, however, comparative data about the cutaneous radical formation are missing. In this study, the radical formation in porcine-, (SKH-1) murine-, human- ex vivo skin and reconstructed human skin (RHS) were investigated during simulated sun irradiation (305-2200 nm), with X-band EPR spectroscopy. The amount of radical formation was investigated with the spin probe PCA exposed to a moderate sun dose below one minimal erythema dose (MED, ~25 mJ/cm2 UVB) in all skin models. Furthermore, the *OH and *CCR radical concentrations were measured with the spin trap DMPO within 0-4 MED (porcine-, human skin and RHS). The highest amount of radicals was found in RHS followed by murine and porcine, and the lowest amount in human ex vivo skin. In all skin models, more *OH than CCR radicals were found at 0-4 MED. Additionally, this work addresses the limitations in the characterization with the spin trap DMPO. The measurements have shown that the most comparable skin model to in vivo human skin could differ depending on the focus of the investigation. If the amount of radial production is regarded, RHS seems to be in a similar range like in vivo human skin. If the investigation is focused on the radical type, porcine skin is most comparable to ex vivo human skin, at an irradiation dose not exceeding 1 MED. Here, no comparison to in vivo human skin is possible.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Radicais Livres/análise , Imageamento Tridimensional/estatística & dados numéricos , Pele/efeitos da radiação , Luz Solar/efeitos adversos , Raios Ultravioleta/efeitos adversos , Animais , Óxidos N-Cíclicos , Relação Dose-Resposta à Radiação , Radicais Livres/química , Humanos , Camundongos , Modelos Biológicos , Estresse Oxidativo , Oxigênio/química , Radiometria , Marcadores de Spin , Suínos , Técnicas de Cultura de Tecidos
16.
Free Radic Biol Med ; 131: 318-331, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30552998

RESUMO

The only general technique that allows the unambiguous detection of free radicals is electron spin resonance (ESR). However, ESR spin trapping has severe limitations especially in biological systems. The greatest limitation of ESR is poor sensitivity relative to the low steady-state concentration of free radical adducts, which in cells and in vivo is much lower than the best sensitivity of ESR. Limitations of ESR have led to an almost desperate search for alternatives to investigate free radicals in biological systems. Here we explore the use of the immuno-spin trapping technique, which combine the specificity of the spin trapping to the high sensitivity and universal use of immunological techniques. All of the immunological techniques based on antibody binding have become available for free radical detection in a wide variety of biological systems.


Assuntos
Anticorpos Monoclonais/química , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Haptenos/química , Detecção de Spin/métodos , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/isolamento & purificação , Galinhas , Óxidos N-Cíclicos/química , Óxidos N-Cíclicos/imunologia , Radicais Livres/análise , Haptenos/imunologia , Soros Imunes/química , Limite de Detecção , Óxidos de Nitrogênio/química , Óxidos de Nitrogênio/imunologia , Pirróis/química , Pirróis/imunologia , Coelhos , Marcadores de Spin , Vacinação
17.
Sci Rep ; 8(1): 16872, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30443039

RESUMO

This study was performed to assess the effect of plasma-discharged water recycling technology as irrigation water on soybean sprout production. Two different types of irrigation water were used individually for cultivation, including plasma discharged water as a source of oxides of nitrogen and tap water, irrigation water was recycled for every 30 minutes. Plasma discharged irrigation water reduced overall 4.3 log CFU/ml aerobic microbe and 7.0 log CFU/ml of artificially inoculated S. Typhimurium within 5 minutes and 2 minutes, respectively, therefore sprout production occurs in a hygienic environment. Using of plasma-discharged water for cultivation, increases the amount of ascorbate, asparagine, and γ-aminobutyric acid (GABA) significantly (p < 0.05), in the part of cotyledon and hypocotyl of soybean sprout during 1 to 4 days of farming. A NO scavenger, 2-(4-carboxy-phenyl)-4,4,5,5-tetramethylimidazoline-1-oxy-3-oxide (cPTIO), was added in irrigation water to elucidate the roles of the oxides of nitrogen such as NO3-, NO2- generated in plasma discharged water. It was observed that all three nutrients decreased in the cotyledon part, whereas ascorbate and GABA contents increased in the hypocotyl and radicle part of bean sprout for the same duration of farming. The addition of NO scavenger in the irrigation water also reduced growth and overall yield of the soybean sprouts. A recycling water system with plasma-discharged water helped to reduce the amount of water consumption and allowed soybean sprouts growth in a hygienic environment during the hydroponic production.


Assuntos
Hidroponia , Nitrogênio/farmacologia , Óxidos/farmacologia , Gases em Plasma/química , Reciclagem , Soja/crescimento & desenvolvimento , Água , Irrigação Agrícola , Ácido Ascórbico/análise , Asparagina/análise , Eletricidade , Eletrodos , Radicais Livres/análise , Viabilidade Microbiana/efeitos dos fármacos , Soja/efeitos dos fármacos , Ácido gama-Aminobutírico/análise
18.
Environ Int ; 121(Pt 1): 260-268, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30223202

RESUMO

Asian dust storms can increase the level of atmospheric pollution over regions downwind of dust storms and may have adverse health effects on residents along the sandstorm transmission route. This study was the first to report the concentration levels, properties and possible sources of environmentally persistent free radicals (EPFRs) and oxidative potential in atmospheric PM2.5 at the three sites of Erenhot, Zhangbei, and Jinan along the transport route of Asian dust storms during the occurrence of Asian dust storms in the spring of 2016. Under non-sandstorm weather conditions, the average EPFR concentrations at the three sites were Zhangbei>Jinan>Erenhot, while the PM-induced oxidative potential levels were Erenhot>Jinan>Zhangbei. The PM2.5 concentration increased significantly during dust storm events, and the total atmospheric concentration of EPFRs (spins/m3) and total oxidation potential (a.u./m3) of PM2.5 simultaneously increased. However, the EPFR concentration in PM2.5 (spins/g) and the unit mass of the PM oxidation potential (a.u./g) were significantly reduced. Electron paramagnetic resonance analysis combined with backward trajectory analysis and MODIS products showed that Asian dust storms can carry EPFRs over long distances. Correlation analysis showed that the atmospheric concentrations of EPFRs were positively correlated with elemental carbon (EC) for the Zhangbei and Jinan samples but were not significantly correlated with EC for the Erenhot samples, indicating that combustion may be an important source of EPFRs for the Zhangbei and Jinan samples. In contrast, the EPFRs in the Erenhot samples were more affected by dust/sand. The EPFR concentration levels showed a significant positive correlation with the oxidation potentials for the Erenhot and Zhangbei samples and showed negative correlations for the Jinan samples, suggesting that the EPFRs in the Erenhot and Zhangbei samples may provide an important contribution to the oxidative stress in PM2.5. In contrast, the oxidation potential for the Jinan samples was mainly caused by substances other than EPFRs. This study presents a basic understanding of the potential health effects of Asian dust storms, and this information can be used to assess the health risks of Asian dust storms in future studies.


Assuntos
Poluentes Atmosféricos/análise , Poeira , Radicais Livres/análise , Estresse Oxidativo , Material Particulado/análise , China , Monitoramento Ambiental , Tempo (Meteorologia)
19.
Parasit Vectors ; 11(1): 500, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-30189903

RESUMO

BACKGROUND: The majority of vaccination studies against infection with F. hepatica in a natural host have been conducted at the late stage of the infection when the host's immune response is already immunomodulated by the parasite towards a Th2 non-protective response. This study was aimed at analysing the dynamic of the cell populations present in peritoneal liquid and the production of free radicals by the peritoneal leukocytes in infected and vaccinated sheep with recombinant cathepsin L1 of F. hepatica (rFhCL1) in early stages of the infection. METHODS: Forty-five sheep were divided into three groups: Group 1 remained as negative control (n = 5), Group 2 (n = 20) was challenged with F. hepatica and Group 3 (n = 20) was vaccinated with rFhCL1 and challenged with F. hepatica. After the slaughtering, peritoneal lavages were carried out at 1, 3, 9 and 18 days post-infection (dpi) to isolate peritoneal cell populations. Flow cytometry was conducted to assess levels of hydrogen peroxide (H2O2) and nitric oxide (NO). RESULTS: There was a significant increase in the total number of leukocytes at 9 and 18 dpi in infected and vaccinated groups. Production of H2O2 was significantly increased in peritoneal granulocytes in both infected and vaccinated groups. Production of nitric oxide showed a significant rise in the granulocytes and monocytes/macrophages in infected and vaccinated sheep. The NO production by granulocytes at 3 and 9 dpi was significantly higher in the vaccinated than in the infected animals. CONCLUSIONS: Experimental infection induced an increase in the total number of leukocytes within the abdominal cavity at 9 and 18 dpi, being more noticeable in vaccinated animals. Production of H2O2 occurred mainly in granulocytes of vaccinated and infected animals. Production of NO was incremented in vaccinated and non-vaccinated animals in all peritoneal cells. Vaccinated animals produced significant higher level of H2O2 and NO than infected animals.


Assuntos
Fasciola hepatica/fisiologia , Peróxido de Hidrogênio/análise , Leucócitos/fisiologia , Óxido Nítrico/análise , Cavidade Peritoneal/citologia , Cavidade Peritoneal/fisiologia , Animais , Anticorpos Anti-Helmínticos/sangue , Anticorpos Anti-Helmínticos/imunologia , Catepsinas/administração & dosagem , Catepsinas/imunologia , Fasciolíase/parasitologia , Radicais Livres/análise , Leucócitos/imunologia , Óxido Nítrico/genética , Cavidade Peritoneal/parasitologia , Ovinos , Doenças dos Ovinos/imunologia , Doenças dos Ovinos/parasitologia , Vacinação
20.
Luminescence ; 33(6): 1101-1106, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29968960

RESUMO

Superoxide radical anion (O2 ˙- ) as an important member of reactive oxygen species (ROS) plays a vital role both in physiology and pathology. Herein we designed and synthesized a novel phosphinate-based bioluminescence probe for O2 ˙- detection in living cells, which exhibited good sensitivity for capturing O2 ˙- at the nanomole level and high selectivity against other ROS. The probe was further found to be of low toxicity for living cells and was then successfully employed for sensing endogenous O2 ˙- by using phorbol-12-myristate-13-acetate (PMA) as a traditional O2 ˙- stimulator in Huh7 cells. Moreover, the increasing production and use of nanoparticles, has given rise to many concerns and debates among the public and scientific authorities regarding their safety and final fate in biological systems. Herein it was found that mondisperse polystyrene particles could stimulate O2 ˙- generation in Huh7 cells. Overall, the probe was demonstrated to have a great potential as a novel bioluminescent sensor for detecting O2 ˙- in living cells. To our knowledge, this is the first small-molecule phosphinate-based bioluminescence probe that will open up great opportunities for unlocking the mystery of O2 ˙- in human health and disease.


Assuntos
Desenho de Fármacos , Substâncias Luminescentes/química , Imagem Óptica , Ácidos Fosfóricos/química , Superóxidos/análise , Ânions/análise , Benzotiazóis/química , Sobrevivência Celular , Células Cultivadas , Luciferina de Vaga-Lumes/química , Radicais Livres/análise , Células HEK293 , Humanos , Substâncias Luminescentes/síntese química , Estrutura Molecular , Ácidos Fosfóricos/síntese química
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