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1.
Environ Monit Assess ; 196(1): 43, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38102340

RESUMO

The northern part of James Ross Island is the largest deglaciated area in the Antarctic Peninsula region with a unique ecosystem created during the Late Glacial. This research aims to evaluate the degree of contamination of the locality with toxic metals (As, Hg, Cd, and Pb) through bioindicators in the aquatic environment-colonies of cyanobacteria and algae. For this purpose, bottom lake sediments of Big Lachman Lake were studied for contents of Fe, As, Hg, Cd, Pb, Cr, Co, Ni, Cu, and Zn, as well as samples of cyanobacterial mat, in which Fe, As, Hg, Cd, and Pb were determined. Metal contents were determined by means of inductively coupled plasma optical emission spectrometry and atomic absorption spectrometry. The contents of metals in sediments did not differ from the usual values in the area of the Antarctic Peninsula. The bioaccumulation of metals in cyanobacterial mat was evaluated by calculating enrichment factors (the calculation to Fe as a reference element). According to this method, moderate pollution of Big Lachman Lake was confirmed for Hg and Cd.


Assuntos
Cianobactérias , Mercúrio , Metais Pesados , Poluentes Químicos da Água , Metais Pesados/análise , Lagos/química , Regiões Antárticas , Ecossistema , Cádmio/análise , Chumbo/análise , Sedimentos Geológicos/química , Monitoramento Ambiental/métodos , Mercúrio/análise , Poluentes Químicos da Água/análise , Medição de Risco
2.
Part Fibre Toxicol ; 19(1): 52, 2022 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-35922858

RESUMO

BACKGROUND: Inhalation of lead oxide nanoparticles (PbO NPs), which are emitted to the environment by high-temperature technological processes, heavily impairs target organs. These nanoparticles pass through the lung barrier and are distributed via the blood into secondary target organs, where they cause numerous pathological alterations. Here, we studied in detail, macrophages as specialized cells involved in the innate and adaptive immune response in selected target organs to unravel their potential involvement in reaction to subchronic PbO NP inhalation. In this context, we also tackled possible alterations in lipid uptake in the lungs and liver, which is usually associated with foam macrophage formation. RESULTS: The histopathological analysis of PbO NP exposed lung revealed serious chronic inflammation of lung tissues. The number of total and foam macrophages was significantly increased in lung, and they contained numerous cholesterol crystals. PbO NP inhalation induced changes in expression of phospholipases C (PLC) as enzymes linked to macrophage-mediated inflammation in lungs. In the liver, the subchronic inhalation of PbO NPs caused predominantly hyperemia, microsteatosis or remodeling of the liver parenchyma, and the number of liver macrophages also significantly was increased. The gene and protein expression of a cholesterol transporter CD36, which is associated with lipid metabolism, was altered in the liver. The amount of selected cholesteryl esters (CE 16:0, CE 18:1, CE 20:4, CE 22:6) in liver tissue was decreased after subchronic PbO NP inhalation, while total and free cholesterol in liver tissue was slightly increased. Gene and protein expression of phospholipase PLCß1 and receptor CD36 in human hepatocytes were affected also in in vitro experiments after acute PbO NP exposure. No microscopic or serious functional kidney alterations were detected after subchronic PbO NP exposure and CD68 positive cells were present in the physiological mode in its interstitial tissues. CONCLUSION: Our study revealed the association of increased cholesterol and lipid storage in targeted tissues with the alteration of scavenger receptors and phospholipases C after subchronic inhalation of PbO NPs and yet uncovered processes, which can contribute to steatosis in liver after metal nanoparticles exposure.


Assuntos
Nanopartículas Metálicas , Fosfolipases Tipo C , Colesterol , Humanos , Inflamação , Chumbo , Macrófagos , Nanopartículas Metálicas/química , Óxidos
3.
Int J Mol Sci ; 21(22)2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33228049

RESUMO

The inhalation of metal (including lead) nanoparticles poses a real health issue to people and animals living in polluted and/or industrial areas. In this study, we exposed mice to lead(II) nitrate nanoparticles [Pb(NO3)2 NPs], which represent a highly soluble form of lead, by inhalation. We aimed to uncover the effects of their exposure on individual target organs and to reveal potential variability in the lead clearance. We examined (i) lead biodistribution in target organs using laser ablation and inductively coupled plasma mass spectrometry (LA-ICP-MS) and atomic absorption spectrometry (AAS), (ii) lead effect on histopathological changes and immune cells response in secondary target organs and (iii) the clearance ability of target organs. In the lungs and liver, Pb(NO3)2 NP inhalation induced serious structural changes and their damage was present even after a 5-week clearance period despite the lead having been almost completely eliminated from the tissues. The numbers of macrophages significantly decreased after 11-week Pb(NO3)2 NP inhalation; conversely, abundance of alpha-smooth muscle actin (α-SMA)-positive cells, which are responsible for augmented collagen production, increased in both tissues. Moreover, the expression of nuclear factor κB (NF-κB) and selected cytokines, such as tumor necrosis factor alpha (TNFα), transforming growth factor beta 1 (TGFß1), interleukin 6(IL-6), IL-1α and IL-1ß , displayed a tissue-specific response to lead exposure. In summary, diminished inflammatory response in tissues after Pb(NO3)2 NPs inhalation was associated with prolonged negative effect of lead on tissues, as demonstrated by sustained pathological changes in target organs, even after long clearance period.


Assuntos
Poluentes Atmosféricos/farmacocinética , Chumbo/farmacocinética , Pulmão/efeitos dos fármacos , Macrófagos Alveolares/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Nitratos/farmacocinética , Actinas/agonistas , Actinas/genética , Actinas/imunologia , Administração por Inalação , Poluentes Atmosféricos/toxicidade , Animais , Disponibilidade Biológica , Feminino , Expressão Gênica , Meia-Vida , Exposição por Inalação/análise , Interleucina-1alfa/agonistas , Interleucina-1alfa/genética , Interleucina-1alfa/imunologia , Interleucina-1beta/agonistas , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-6/agonistas , Interleucina-6/genética , Interleucina-6/imunologia , Chumbo/toxicidade , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/patologia , Pulmão/imunologia , Pulmão/patologia , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/patologia , Nanopartículas Metálicas/administração & dosagem , Camundongos , Camundongos Endogâmicos ICR , NF-kappa B/agonistas , NF-kappa B/genética , NF-kappa B/imunologia , Nitratos/toxicidade , Espectrofotometria Atômica , Distribuição Tecidual , Fator de Crescimento Transformador beta1/agonistas , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/imunologia , Fator de Necrose Tumoral alfa/agonistas , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
4.
Environ Monit Assess ; 192(2): 89, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31902034

RESUMO

Soybeans, as legumes, belong among food items that contribute most to the dietary intake of the heavy metal cadmium (Cd). The consumption of soy-based foods may contribute significantly to Cd intake in vegetarians as probably the most frequent consumers of these foods. In this research, the weekly dietary intake of Cd from soy-based foods was investigated in 119 participants (including vegetarians, vegans, and non-vegetarians) in the Czech Republic by means of a semi-quantitative food frequency questionnaire (SFFQ) with personal assistance and the measurement of body weight. Cd content in soy-based foods available on the market was determined by means of atomic absorption spectrometry after microwave digestion. Tofu, as the most frequently consumed food item in the vegetarian/vegan group, contributed most to the total dietary Cd intake. It contained 7.6 ± 0.1 µg Cd/kg, while the highest Cd content was observed in tempeh (18.1 ± 0.4 µg/kg). The highest mean dietary Cd intake per week from soy-based foods was 0.4 µg/kg b.w. and was found in the vegan group. The consumption of soy-based foods was the lowest in the non-vegetarian group as was the dietary intake of Cd, which was 0.04 µg/kg b.w. per week.


Assuntos
Cádmio/análise , Exposição Dietética/estatística & dados numéricos , Contaminação de Alimentos/estatística & dados numéricos , Glycine max/química , Poluentes do Solo/análise , Alimentos de Soja/análise , Peso Corporal , República Tcheca , Dieta , Monitoramento Ambiental , Fabaceae , Feminino , Humanos , Masculino , Espectrofotometria Atômica , Verduras , Vegetarianos
5.
Environ Monit Assess ; 192(4): 222, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32146527

RESUMO

The determination of trace metal contents directly from a solid sample is a trend in modern atomic spectrometry. The aim of this study was to develop an analytical method for the routine determination of Cd in lichens using solid sampling graphite furnace atomic absorption spectrometry (SS-GF-AAS). For the determination of Cd, the temperature program of the graphite furnace was optimized using a mixed matrix modifier (Pd + Mg (NO3)2 + Triton X-100). The limit of detection and the limit of quantification were 0.9 µg/kg and 3 µg/kg, respectively. The analytical method for Cd determination in the plant matrix was verified by the analysis of certified reference materials of lichens, seaweed, and rye grass. The developed procedure was applied to the study of Cd distribution in thalli of Usnea antarctica lichen from James Ross Island, Antarctica. The SS-GF-AAS analytical method is particularly suited for use in environmental studies and plant physiology (the microanalysis of anatomical structures).


Assuntos
Cádmio , Poluentes Ambientais , Grafite , Líquens , Regiões Antárticas , Cádmio/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Ilhas , Líquens/química , Espectrofotometria Atômica
6.
Environ Monit Assess ; 192(12): 771, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33215318

RESUMO

In this study, the occurrence of lead (Pb), cadmium (Cd), copper (Cu), and zinc (Zn) in the environment of the Moravian Library in Brno, the second largest library in Czechia, was in focus. The materials of interest were airborne particles, dust originating from books, and also book pages. Total suspended particles (TSP) were sampled in different areas of the library, including the reading room, the book depository, and an external book warehouse. Samples of dusts were obtained from the book-cleaning system, and, moreover, some pages taken from old books were also analyzed. Samples were microwave-digested and analyzed using graphite furnace high-resolution continuum source AAS (HR-CS GF-AAS). During the analysis, possibilities of the signal intensity modulation of the HR-CS technique were demonstrated and employed in order to determine Zn, an element which is rarely determined by GF-AAS. The median TSP concentrations (in ng/m3) were as follows: Pb, 4.4; Cd, 0.07; Cu, 2.6; and Zn, 20.9. Such concentrations are safely below allowed limits. Contents of Pb determined in dust samples and book pages were slightly higher (up to 707 and 38 mg/kg, respectively) than the usually reported values. However, none of these results indicate a potential risk to library staff or readers.


Assuntos
Poluentes Ambientais , Metais Pesados , Cádmio/análise , Poeira/análise , Monitoramento Ambiental , Humanos , Chumbo , Metais Pesados/análise , Zinco
7.
Environ Monit Assess ; 191(3): 181, 2019 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-30798372

RESUMO

Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was applied for the determination of Cd and Zn distributions within the leaves of Cd- and Zn-hyperaccumulating plants, Noccaea caerulescens, N. praecox, and Arabidopsis halleri, in contrast to nonaccumulator species, Thlaspi arvense and A. thaliana. The elemental mapping of the selected leaf area was accomplished via line scans with a 110-µm-diameter laser beam at a 37-µm s-1 scan speed and repetition rate of 10 Hz. The lines were spaced 180 µm apart and ablated at an energy density of 2 J cm-2. The elemental imaging clearly confirmed that Cd was predominantly distributed within the parenchyma of the T. arvense, whereas in the Noccaea spp. and A. halleri, the highest intensity Cd signal was observed in the veins of the leaves. For Zn, higher intensities were observed in the veins for all the plant species except for A. thaliana. Close relationships between Zn and Ca were identified for the Noccaea spp. leaves. These relationships were not confirmed for A. halleri. Significant correlations were also proved between the Cd and Zn distribution in A. halleri, but not for the Noccaea spp. For both T. arvense and A. thaliana, no relevant significant relationship for the interpretation of the results was observed. Thus, the LA-ICP-MS imaging is proved as a relevant technique for the description and understanding of the elements in hyperaccumulating or highly accumulating plant species, although its sensitivity for the natural element contents in nonaccumulator plant species is still insufficient.


Assuntos
Monitoramento Ambiental , Oligoelementos/análise , Arabidopsis/química , Brassicaceae/química , Cádmio , Folhas de Planta/química , Raízes de Plantas , Thlaspi/química , Zinco
8.
Bull Environ Contam Toxicol ; 101(5): 554-555, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30288549

RESUMO

The original version of this article contained a mistake in Fig. 2. The country names have been missed in the figure legend along with the X-axis. The corrected figure is given below.

9.
Bull Environ Contam Toxicol ; 101(5): 549-553, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30167763

RESUMO

Volcanic activity is one of the primary sources of mercury in the earth's ecosystem. In this work, volcanic rocks from four geotectonically distinct localities (the Czech Republic - intraplate, rift-related alkaline basaltic rocks; Iceland - hotspot/rift-related tholeiitic basaltic rocks; Japan - island arc calc-alkaline andesites; and Alaska - continental arc calc-alkaline dacites) were studied. Ultra-trace Hg contents in all samples ranged from 0.3 up to 6 µg/kg. The highest Hg content was determined for volcanic ash from Mount Redoubt (Alaska, USA). In the case of basaltic volcanic rocks, the obtained results are about two orders of magnitude smaller than values formerly assumed for primary mercury contents in basaltic lavas. They are close to predicted Hg contents in the mantle source, i.e. below 0.5 µg/kg. Hg degassing is probably a key process for the resulting Hg contents in material ejected during volcanic eruption, which is previously enriched by Hg in the shallow-crust.


Assuntos
Mercúrio/análise , Silicatos/análise , Erupções Vulcânicas/análise
10.
Environ Monit Assess ; 190(1): 13, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29230543

RESUMO

Lichens are efficient and cost-effective biomonitors of the environment. Their geographic distribution together with their slow growth rate enable investigation of the deposition patterns of various elements and substances. In this research, levels of cadmium, lead, and mercury in Usnea antarctica lichens in the area of James Ross Island, Antarctica, were investigated. The lichens were microwave-digested, and the metals were determined by means of atomic absorption spectrometry with graphite furnace and a direct mercury analyzer. Median total contents of Cd, Hg, and Pb were 0.04, 0.47, and 1.6 mg/kg in whole lichens, respectively. The bottom-up distributions of these metals in the fruticose lichen thalli were investigated, and it was revealed that the accumulation patterns for mercury and lead were opposite to that for cadmium. The probable reason for this phenomenon may lie in the inner structure of thalli. The total contents of metals were comparable with those published for other unpolluted areas of maritime Antarctica. However, this finding was not expected for mercury, since the sampling locality was close to an area with some of the highest mercury contents published for Antarctic lichens. In short, lichens proved their usability as biological monitors, even in harsh conditions. However, the findings emphasize the need to take into account the distributions of elements both in the environment and in the lichen itself.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Metais/análise , Usnea/química , Regiões Antárticas , Ascomicetos , Cádmio/análise , Ilhas , Chumbo/análise , Líquens/química , Mercúrio/análise , Quinolonas , Espectrofotometria Atômica
11.
Artigo em Inglês | MEDLINE | ID: mdl-26761522

RESUMO

The precise characterization of the behavior of individual microorganisms in the presence of increased mercury contents in soil is necessary for better elucidation of the fate of mercury in the soil environment. In our investigation, resistant bacterial strains isolated from two mercury contaminated soils, represented by Paenibacillus alginolyticus, Burkholderia glathei, Burkholderia sp., and Pseudomonas sp., were used. Two differently contaminated soils (0.5 and 7 mg kg(-1) total mercury) were chosen. Preliminary soil analysis showed the presence of methylmercury and phenylmercury with the higher soil mercury level. Modified rhizobox experiments were performed to assess the ability of mercury accumulating strains to deplete the mobile and mobilizable mercury portions in the soil by modification; microbial agar cultures were used rather than the plant root zone. A sequential extraction procedure was performed to release the following mercury fractions: water soluble, extracted in acidic conditions, bound to humic substances, elemental, and bound to complexes, HgS and residual. Inductively coupled plasma mass spectrometry (ICP-MS) and a single-purpose atomic absorption spectrometer (AMA-254) were applied for mercury determination in the samples and extracts. Gas chromatography coupled to atomic fluorescence spectrometry (GC-AFS) was used for the determination of organomercury compounds. The analysis of the microbial community at the end of the experiment showed a 42% abundance of Paenibacillus sp. followed by Acetivibrio sp., Brevibacillus sp., Cohnella sp., Lysinibacillus sp., and Clostridium sp. not exceeding 2% abundance. The results suggest importance of Paenibacillus sp. in Hg transformation processes. This genus should be tested for potential bioremediation use in further research.


Assuntos
Bactérias/metabolismo , Poluição Ambiental/análise , Compostos de Mercúrio/análise , Mercúrio/análise , Compostos de Metilmercúrio/análise , Microbiologia do Solo , Poluentes do Solo/análise , Biodegradação Ambiental , Cromatografia Gasosa , Monitoramento Ambiental/métodos , Mercúrio/química , Compostos de Mercúrio/química , Compostos de Metilmercúrio/química , Poluentes do Solo/química , Espectrometria de Fluorescência , Espectrofotometria Atômica
12.
Environ Monit Assess ; 186(12): 9089-100, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25261983

RESUMO

The study was designed to investigate the content and distribution of selected heavy metals (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Fe, Pb and Zn) in samples of fruticose macrolichen Usnea antarctica from James Ross Island. A special emphasis was devoted to mercury and its species (elemental mercury and methylmercury). It was found that mercury contents were relatively high (up to 2.73 mg kg(-1) dry weight) compared to other parts of the Antarctic Peninsula region, while the concentrations of most other elements were within reported ranges. Mercury contents in lichens originating from the interior were higher than those from the coast, which is probably the result of local microclimate conditions. Similar trends were observed for Hg(0) and MeHg(+), whose contents were up to 0.14 and 0.098 mg kg(-1) dry weight, respectively. While mercury did not show a significant correlation with any other element, the mutual correlation of some litophile elements probably refers to the influence on thalli of resuspended weathered material. The influence of habitat and environmental conditions could play an essential role in the bioaccumulation of contaminants rather than just the simple presence of sources. Thus, the study of the thalli of this species can bring a new perspective on the interpretation of contaminant accumulation in lichens of the polar region.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Usnea/química , Regiões Antárticas , Ecossistema , Ilhas , Líquens/química , Mercúrio/análise
13.
Bull Environ Contam Toxicol ; 93(4): 503-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24816804

RESUMO

Environmental contamination by mercury carries serious risks to the biosphere. Urban agglomerations burdened with traffic are characterized by substantial dust levels, including high concentrations of pollutants bound to particulate matter. In this research, the content of particulate mercury in street dust was investigated in relation to the season and traffic intensity. In total, 80 street dust samples were collected in the centre of Brno (Czech Republic) in which total and bioaccessible mercury contents were determined. Total mercury content in the samples ranged from 0.03 to 2.67 mg/kg. The content of bioaccessible mercury was below the limit of quantification in all samples. Thus, street dust did not increase the daily mercury intake by the population in studied area. A clear trend of mercury accumulation in street dust depending on traffic intensity in the investigated streets was not observed over the whole year.


Assuntos
Poeira/análise , Monitoramento Ambiental/estatística & dados numéricos , Poluição Ambiental/análise , Substâncias Perigosas/análise , Mercúrio/análise , Estações do Ano , República Tcheca , Monitoramento Ambiental/métodos , Espectrofotometria Atômica
14.
Nanomaterials (Basel) ; 13(4)2023 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-36839135

RESUMO

Titanium dioxide nanoparticles (TiO2 NPs) are used in a wide range of applications. Although inhalation of NPs is one of the most important toxicologically relevant routes, experimental studies on potential harmful effects of TiO2 NPs using a whole-body inhalation chamber model are rare. In this study, the profile of lymphocyte markers, functional immunoassays, and antioxidant defense markers were analyzed to evaluate the potential adverse effects of seven-week inhalation exposure to two different concentrations of TiO2 NPs (0.00167 and 0.1308 mg TiO2/m3) in mice. A dose-dependent effect of TiO2 NPs on innate immunity was evident in the form of stimulated phagocytic activity of monocytes in low-dose mice and suppressed secretory function of monocytes (IL-18) in high-dose animals. The effect of TiO2 NPs on adaptive immunity, manifested in the spleen by a decrease in the percentage of T-cells, a reduction in T-helper cells, and a dose-dependent decrease in lymphocyte cytokine production, may indicate immunosuppression in exposed mice. The dose-dependent increase in GSH concentration and GSH/GSSG ratio in whole blood demonstrated stimulated antioxidant defense against oxidative stress induced by TiO2 NP exposure.

15.
Front Immunol ; 13: 874253, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35547729

RESUMO

Copper oxide nanoparticles (CuO NPs) are increasingly used in various industry sectors. Moreover, medical application of CuO NPs as antimicrobials also contributes to human exposure. Their toxicity, including toxicity to the immune system and blood, raises concerns, while information on their immunotoxicity is still very limited. The aim of our work was to evaluate the effects of CuO NPs (number concentration 1.40×106 particles/cm3, geometric mean diameter 20.4 nm) on immune/inflammatory response and antioxidant defense in mice exposed to 32.5 µg CuO/m3 continuously for 6 weeks. After six weeks of CuO NP inhalation, the content of copper in lungs and liver was significantly increased, while in kidneys, spleen, brain, and blood it was similar in exposed and control mice. Inhalation of CuO NPs caused a significant increase in proliferative response of T-lymphocytes after mitogenic stimulation and basal proliferative activity of splenocytes. CuO NPs significantly induced the production of IL-12p70, Th1-cytokine IFN-γ and Th2-cytokines IL-4, IL-5. Levels of TNF-α and IL-6 remained unchanged. Immune assays showed significantly suppressed phagocytic activity of granulocytes and slightly decreased respiratory burst. No significant differences in phagocytosis of monocytes were recorded. The percentage of CD3+, CD3+CD4+, CD3+CD8+, and CD3-CD19+ cell subsets in spleen, thymus, and lymph nodes did not differ between exposed and control animals. No changes in hematological parameters were found between the CuO NP exposed and control groups. The overall antioxidant protection status of the organism was expressed by evaluation of GSH and GSSG concentrations in blood samples. The experimental group exposed to CuO NPs showed a significant decrease in GSH concentration in comparison to the control group. In summary, our results indicate that sub-chronic inhalation of CuO NPs can cause undesired modulation of the immune response. Stimulation of adaptive immunity was indicated by activation of proliferation and secretion functions of lymphocytes. CuO NPs elicited pro-activation state of Th1 and Th2 lymphocytes in exposed mice. Innate immunity was affected by impaired phagocytic activity of granulocytes. Reduced glutathione was significantly decreased in mice exposed to CuO NPs.


Assuntos
Cobre , Nanopartículas , Imunidade Adaptativa , Animais , Antioxidantes , Cobre/toxicidade , Citocinas , Camundongos , Nanopartículas/toxicidade , Óxidos
16.
J Trace Elem Med Biol ; 68: 126869, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34601283

RESUMO

BACKGROUND: High-resolution continuum source AAS is an emerging technique for the determination of trace elements in clinical analysis. We aimed to develop a method for the direct determination of platinum (Pt) in pleural effusions that could deepen the understanding of the dynamics of intrapleural Pt concentration during cytostatic therapy. MATERIALS AND METHODS: Samples were collected by thoracic drainage from five patients with lung cancer undergoing platinum based chemotherapy. A simple dilute-and-shoot method for Pt determination in the pleural effusions was developed. Ashing of the sample in an oxygen flow in a graphite tube allowed for direct analysis without prior mineralization. The trueness of the method was verified using an independent technique (ICP-MS). As platinum derivatives are only active in its free form (not bound to proteins), Pt in samples was further divided into free and protein-bound forms by means of ultrafiltration. RESULTS: Using the proposed method, Pt contents (free and total) were determined in samples collected at different times after the intravenous application of the Pt derivative. The concentration of total Pt reached values of up to 5,000 µg/L and different patterns of its dynamics in intrapleural fluid were observed. CONCLUSIONS: The developed method enables the fast and simple determination of Pt in biological fluids. It may be applied on a large scale to improve the understanding of Pt dynamics during cytostatic therapy, and also to determine the optimal timing of both thoracic drainage and administration of systemic chemotherapy.


Assuntos
Citostáticos , Grafite , Neoplasias Pulmonares , Derrame Pleural , Humanos , Platina , Derrame Pleural/tratamento farmacológico
17.
Nanomaterials (Basel) ; 10(3)2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32197515

RESUMO

We investigated the transcriptomic response and epigenetic changes in the lungs of mice exposed to inhalation of copper(II) oxide nanoparticles (CuO NPs) (8 × 105 NPs/m3) for periods of 3 days, 2 weeks, 6 weeks, and 3 months. A whole genome transcriptome and miRNA analysis was performed using next generation sequencing. Global DNA methylation was assessed by ELISA. The inhalation resulted in the deregulation of mRNA transcripts: we detected 170, 590, 534, and 1551 differentially expressed transcripts after 3 days, 2 weeks, 6 weeks, and 3 months of inhalation, respectively. Biological processes and pathways affected by inhalation, differed between 3 days exposure (collagen formation) and longer treatments (immune response). Periods of two weeks exposure further induced apoptotic processes, 6 weeks of inhalation affected the cell cycle, and 3 months of treatment impacted the processes related to cell adhesion. The expression of miRNA was not affected by 3 days of inhalation. Prolonged exposure periods modified miRNA levels, although the numbers were relatively low (17, 18, and 38 miRNAs, for periods of 2 weeks, 6 weeks, and 3 months, respectively). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analysis based on miRNA-mRNA interactions, revealed the deregulation of processes implicated in the immune response and carcinogenesis. Global DNA methylation was not significantly affected in any of the exposure periods. In summary, the inhalation of CuO NPs impacted on both mRNA and miRNA expression. A significant transcriptomic response was already observed after 3 days of exposure. The affected biological processes and pathways indicated the negative impacts on the immune system and potential role in carcinogenesis.

18.
ACS Nano ; 14(3): 3096-3120, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32105447

RESUMO

Lead oxide nanoparticles (PbONPs), upon their entry into the lungs via inhalation, induce structural changes in primary and secondary target organs. The fate and ultrastructural localization of PbONPs in organs is known to be dependent on the specific organ. Here, we focused on the differences in the ability to clear the inhaled PbONPs from secondary target organs and on molecular and cellular mechanisms contributing to nanoparticle removal. Mice were exposed to PbONPs in whole-body inhalation chambers. Clearance of ionic lead and PbONPs (Pb/PbONPs) from the lungs and liver was very effective, with the lead being almost completely eliminated from the lungs and the physiological state of the lung tissue conspicuously restored. Kidneys exposed to nanoparticles did not exhibit serious signs of damage; however, LA-ICP-MS uncovered a certain amount of lead located preferentially in the kidney cortex even after a clearance period. The concentration of lead in femurs, as representatives of the axial skeleton, was the highest among studied organs at all designated time points after PbONP exposure, and the clearance ability of lead from the femurs was very low in contrast to other organs. The organ-specific increase of ABC transporters expression (ABCG2 in lungs and ABCC3 in the liver) was observed in exposed animals, suggesting their involvement in removing Pb/PbONPs from tissues. Moreover, the expression of caveolins and clathrin displayed a tissue-specific response to lead exposure. Our results uncovered high variability among the organs in their ability to clear Pb/PbONPs and in the transporters involved in this process.


Assuntos
Chumbo/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Nanopartículas/metabolismo , Óxidos/metabolismo , Animais , Feminino , Chumbo/administração & dosagem , Chumbo/química , Fígado/química , Fígado/metabolismo , Pulmão/química , Pulmão/metabolismo , Proteínas de Membrana Transportadoras/química , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/administração & dosagem , Nanopartículas/química , Óxidos/administração & dosagem , Óxidos/química
19.
Food Chem Toxicol ; 136: 110954, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31707033

RESUMO

Due to the growing number of applications of cadmium oxide nanoparticles (CdO NPs), there is a concern about their potential deleterious effects. The objective of our study was to investigate the effect of CdO NPs on the immune response, renal and intestine oxidative stress, blood antioxidant defence, renal fibrotic response, bone density and mineral content. Six-week-old female ICR mice were exposed to CdO NPs for 6 weeks by inhalation (particle size: 9.82 nm, mass concentration: 31.7 µg CdO/m3, total deposited dose: 0.195 µg CdO/g body weight). CdO NPs increased percentage of thymus CD3e+CD8a+ cells and moderately enhanced splenocyte proliferation and production of cytokines and chemokines. CdO NPs elevated pro-fibrotic factors (TGF-ß2, α-SMA and collagen I) in the kidney, and concentrations of AGEs in the intestine. The ratio of GSH and GSSG in blood was slightly reduced. Exposure to CdO NPs resulted in 10-fold higher Cd concentration in tibia bones. No differences were found in bone mass density, mineral content, bone area values, bone concentrations of Ca, P, Mg and Ca/P ratio. Our findings indicate stimulation of immune/inflammatory response, oxidative stress in the intestine, starting fibrotic response in kidneys and accumulation of CdO NPs in bones of mice.


Assuntos
Compostos de Cádmio/toxicidade , Fibrose/induzido quimicamente , Imunidade Celular/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Óxidos/toxicidade , Tíbia/efeitos dos fármacos , Administração por Inalação , Animais , Compostos de Cádmio/administração & dosagem , Citocinas/metabolismo , Feminino , Intestinos/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Linfonodos/efeitos dos fármacos , Nanopartículas Metálicas/administração & dosagem , Camundongos Endogâmicos ICR , Óxidos/administração & dosagem , Baço/efeitos dos fármacos , Timo/efeitos dos fármacos
20.
Food Chem ; 298: 125084, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260980

RESUMO

A method for simultaneous determination of cadmium and iron in cereal flakes using high-resolution continuum source graphite furnace atomic absorption spectrometry is presented. Sample digest is introduced into the graphite furnace together with Pd/Mg(NO3)2 modifier. The primary absorption line of cadmium and adjacent secondary line of iron are used for the determination. Atomization is performed as a two-step process in order to meet ideal conditions for both elements. Interference produced by molecular absorption of PO molecular bands is suppressed by correction model using least squares background correction. Using the proposed method, levels of cadmium and iron were determined in different kinds of cereal flakes, where both elements are of great interest. Working range (0.01-2 µg L-1 for Cd and 10-500 µg L-1 for Fe) was suitable for the determination of analytes in samples. The method is fast, robust, and may be routinely used routinely in the analysis of foodstuffs.


Assuntos
Cádmio/análise , Grão Comestível/química , Análise de Alimentos/métodos , Ferro/análise , Espectrofotometria Atômica/métodos , Grafite/química
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