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1.
Toxics ; 11(7)2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37505517

RESUMO

Atmospheric bulk and wet deposition samples were collected simultaneously at the background coastal site in the Eastern Middle Adriatic region in order to assess the impact of major ions (Cl-, NO3-, SO42-, Na+, K+, NH4+, Mg2+, Ca2+) on deposition acidity and distinguish the main sources. Higher ion levels were observed during the cold period, especially for Cl-, Na+, Mg2+ and K+. Dust intrusion caused significant increases in levels of Ca2+, Mg2+ and K+, while open-fire events increased the levels of K+. Deposition acidity showed seasonal differences as well as the influence of dust intrusion. Low ionic balance ratios indicated acidic deposition properties and the presence of organic anions. The highest neutralization ability was found for Ca2+, Na+ and NH4+. Several natural (marine, crustal) and anthropogenic sources were determined, as well as the formation of secondary aerosols. Wet deposition was characterized by higher contribution of sea salt fraction compared to bulk deposition and lower contribution of crustal fraction.

2.
Sci Total Environ ; 838(Pt 3): 156440, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35660618

RESUMO

Atmospheric deposition (AD) of nutrients and its impact on the sea surface requires consideration of interfacial processes within the sea surface microlayer (SML), the ocean-atmosphere boundary layer of major importance for many global biogeochemical and climate-related processes. This study comprised a comprehensive dataset, including dissolved NO3-, NH4+ and PO43- in ambient aerosol particles, wet deposition and sea surface samples collected from February to July 2019 at a central Adriatic coastal site. The aerosol mean concentration of dissolved nitrogen (DIN = NO3- + NH4+) and PO43- were 48.8 ± 82.8 µmol m-3 and 0.8 ± 0.6 µmol m-3, respectively, while their total fluxes (dry + wet) ranged from 24.2 to 212.3 µmol m-2 d-1 (mean 123.2 ± 53.2 µmol m-2 d-1) and from 1.2 to 2.1 µmol m-2 d-1 (mean 1.5 ± 0.3 µmol m-2 d-1), respectively. Intensive local episodes of open biomass burning (BB) significantly increased aerosol DIN concentrations as well as DIN deposition fluxes, particularly altering the molar DIN/PO43- ratio of atmospheric samples. The DIN temporal patterns showed high variability in the SML (range 0.2-24.6 µmol L-1, mean 5.0 ± 7.1 µmol L-1) in contrast to the underlying water samples (range 0.5-4.2 µmol L-1, mean 1.9 ± 1.2 µmol L-1), with significant increases during BB periods. Variability in abundance of heterotrophic bacteria and autotrophs in the SML along with concentrations of bulk dissolved and particulate organic carbon as well as dissolved and particulate lipids and carbohydrates, gel particles and surfactants followed DIN enhancements with a two-week delay. This study showed that AD can affect the short-term scale enrichments of organic matter in the SML, especially when accompanied by BB emissions typical of the overall Mediterranean coastal environment. This could have strong implications for global air-sea exchange processes, including those of climate relevant gases, mediated by the SML.


Assuntos
Atmosfera , Água do Mar , Aerossóis/análise , Poeira , Monitoramento Ambiental , Nitrogênio/análise , Água do Mar/química
3.
Mar Pollut Bull ; 172: 112873, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34428622

RESUMO

First data on polycyclic aromatic hydrocarbons (PAHs) and nitro-aromatic compounds (NACs) in aerosols as well as of PAHs, polychlorinated biphenyls (PCBs) and NACs in bulk and wet atmospheric deposition samples were simultaneously obtained during 6-month-long field campaign at the costal central Adriatic area. Special attention was given to open-fire biomass burning episodes as extreme events common for the overall Mediterranean coastal area in order to gain a better understanding of the atmospheric variabilities and potential sources of trace organic pollutants in coastal environments. Diesel and gasoline combustion related to land and maritime traffic as well as occasional open-fire episodes (forest fires) were found to be the dominant pollution sources of PAHs in PM10 particles. NACs were determined almost exclusively in samples affected by biomass burning episodes. Open-fire episodes had a strong contribution to the overall NACs atmospheric deposition fluxes. Several chlorinated congeners of PCBs were predominantly contributed in deposition samples.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Hidrocarbonetos Policíclicos Aromáticos , Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise
4.
Arh Hig Rada Toksikol ; 71(2): 130-137, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32975099

RESUMO

Garlic is a valuable source material for medicines due to its known antitumor, hypolipidaemic, antioxidant, and immunomodulatory effects. This study compares the protective effects of conventionally grown (CG) and in vitro propagated garlic (PG) against hydrogen peroxide-induced cytotoxicity in HepG2 cells and their antioxidant activity. Garlic used in this study was obtained by planting garlic cloves or by planting the transplants of PG directly in the field. At the end of the vegetation period, CG and PG were sampled and extracts prepared for the experiment. Compared to conventionally grown garlic bulbs, PG leafy part yielded significantly higher content of polyphenols, flavonoids and alliin, and also showed equal or higher antioxidant activity, measured by the cell viability test, GSH and ROS level. Moreover, PG can be produced in less time (shorter vegetation period) and with significantly less material (cloves). Significantly higher content of alliin, polyphenols, and flavonoids and significantly higher yield of plant biomass in PG has a great potential to become a new production model with improved garlic properties as a medicine material.


Assuntos
Carcinoma Hepatocelular , Alho , Neoplasias Hepáticas , Antioxidantes/farmacologia , Humanos , Peróxido de Hidrogênio/toxicidade , Extratos Vegetais/farmacologia
5.
Drug Chem Toxicol ; 40(2): 228-234, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27387363

RESUMO

Circulating platinum (Pt) is detectable in the blood of Pt-treated cancer patients for over a decade after the treatment. Prolonged exposure to Pt, in combination with adverse compounds from nutrition and lifestyle, such as cadmium (Cd), could increase the risk from second cancers. The aim of this study was to investigate the effects of simultaneous exposure to Cd- and Pt-compounds on oxidative and DNA damage and the possible protective effects of zinc (Zn) and selenium (Se). The aqueous solutions of PtCl4, CdCl2 × H2O, ZnCl2 and Na2SeO3 were added, alone or in combination, to whole blood and isolated erythrocytes to produce the final concentrations of 2000 µg/L of Pt, 8 µg/L of Cd, 100 µg/L of Se, and 1000 µg/L of Zn. The activity of copper, zinc-superoxide dismutase, glutathione peroxidase and glutathione in whole blood was determined after 1 h exposure in in vitro conditions. The induction of DNA strand-breaks in human peripheral blood leukocytes was determined with the alkaline comet assay after 24 h exposure. Exposure to Pt and/or Cd decreased the activities of antioxidant enzymes and elevated DNA damage compared to control. A statistically significant change in the activity of both enzymes and in the induction of DNA strand-breaks was observed in the cells treated with Pt + Cd combination, while the addition of Se and/or Zn resulted in partial recovery of these effects. The results indicate that combined exposure to Pt and Cd could disrupt antioxidant protection of the organism and increase DNA damage, whereas Se and Zn could partially ameliorate these harmful effects.


Assuntos
Antioxidantes/farmacologia , Cloreto de Cádmio/toxicidade , Cloretos/farmacologia , Dano ao DNA/efeitos dos fármacos , Enzimas/sangue , Mutagênicos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Compostos de Platina/toxicidade , Selenito de Sódio/farmacologia , Compostos de Zinco/farmacologia , Adulto , Biomarcadores/sangue , Ensaio Cometa , Citoproteção , Eritrócitos/efeitos dos fármacos , Eritrócitos/enzimologia , Glutationa/sangue , Glutationa Peroxidase/sangue , Humanos , Leucócitos/efeitos dos fármacos , Leucócitos/enzimologia , Leucócitos/patologia , Masculino , Superóxido Dismutase/sangue , Adulto Jovem
6.
Artigo em Inglês | MEDLINE | ID: mdl-27776688

RESUMO

Since the incidence of cancer has increased over the years, adequate prevention programmes are needed. Thyroid cancer is one of the fastest growing cancer types in the world. In this study we performed a case-control study of 100 untreated patients with thyroid diseases (papillary thyroid cancer, follicular thyroid adenoma, and other thyroid diseases) and 100 control volunteers. Oxidative status differed among the two investigated groups. The patients' group had 1.60-fold higher concentrations of malondialdehyde and 1.26-fold higher concentrations of protein carbonyls. At the same time, the concentrations of glutathione and catalase activity were by 32% and 35% lower, respectively. A similar effect was observed for the cytogenetic status where higher comet assay tail intensity (1.84-fold) and the total numbers of chromosome aberrations (1.47-fold), micronuclei (2.32-fold), nucleoplasmic bridges (3.98-fold), and nuclear buds (2.34-fold) were detected. As for protein expression in thyroid tissue, 97.89% were positive for either B-Raf or Ret. Interestingly, the papillary thyroid cancer patients more frequently expressed B-Raf proteins compared to the follicular thyroid adenoma patients and patients with other thyroid diseases. Human biomonitoring studies enable a risk assessment of general population, such data could be used to identify risk subgroups.


Assuntos
Estresse Oxidativo , Doenças da Glândula Tireoide/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Aberrações Cromossômicas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças da Glândula Tireoide/genética
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