Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 107
Filtrar
1.
Drug Chem Toxicol ; 45(1): 185-196, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31621443

RESUMO

North-eastern states of India, including Assam, have a high prevalence of head and neck cancer cases. In these regions, Sadagura is a unique form of smokeless tobacco (SLT). There are fewer reports regarding the effects of simultaneous sadagura and arsenic co-exposure. Analysis of chemical compounds present in sadagura aqueous extract was done using gas chromatography-mass spectrometry. Estimation of arsenic contamination in groundwater and bioaccumulation in human tissues was performed by using atomic absorption spectroscopy. Buccal micronucleus cytome (BMCyt) assay and analysis of various peripheral blood parameters were performed among study volunteers. Chronic exposure (90 days) experiments were performed in mice test system in vivo to determine any possible protective potential of vitamin C (Vit-C) supplementation against sadagura and arsenic co-exposure. BMCyt assay results revealed a higher incidence of micronucleated cells (p < 0.001), and cell death biomarker among sadagura consumers residing in arsenic affected areas. Comet assay of mice femur bone marrow cells following chronic exposure of the test substances revealed a reduction in DNA damage due to Vit-C supplementation. Histological examination of the hepatic and renal tissues revealed marked improvement due to Vit-C supplementation in mice against sadagura and arsenic chronic co-exposure. Indiscriminate consumption, presence of various harmful compounds in sadagura along with arsenic co-exposure might be a vital link for the higher incidence of oral cancer in the region. Chronic Vit-C supplementation study results in mice show its effective remedial potential against combined sadagura and arsenic co-mediated genotoxicity and ultrastructural changes in major organs.


Assuntos
Arsênio , Tabaco sem Fumaça , Animais , Arsênio/toxicidade , Dano ao DNA , Suplementos Nutricionais , Cromatografia Gasosa-Espectrometria de Massas , Instabilidade Genômica , Camundongos , Testes para Micronúcleos , Tabaco sem Fumaça/toxicidade , Vitaminas
2.
J Environ Manage ; 304: 114229, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34922188

RESUMO

The main objectives of this study were to evaluate the Cu, Zn, Pb, Cr and Ni mobility using modified Tessier sequential extraction procedure and to study the functional group changes affected by each extraction step using FTIR analysis in the soil of a former sewage farm sedimentation basin. Tessier extraction revealed element dependent fractionation of studied metals: Pb was mostly discovered in the residual fraction (77%) followed by Cr (53%), Cu (8%), and Zn (5%), while Ni was not extracted in this fraction. The organic matter-bound was the dominant species of Cu (77%). Zn and Ni exhibited the highest affinity for Fe/Mn oxides fraction (55% and 39%, respectively). The average recovery rate was 62-111%, whereas the lowest rate was obtained for Ni (62%) and the highest for Cu/Pb (110-111%). Results indicated elevated concentrations of studied elements, with the following order of mobility factor: Ni > Zn > Cu > PbCr. The preliminary interpretation of the sequential extraction FTIR spectral response revealed that DRIFT is applicable to interpret the sequential metal extraction and revealed three most profound changes correlated to the carbonate, Fe/Mn oxides, and OM fraction.


Assuntos
Metais Pesados , Poluentes do Solo , Monitoramento Ambiental , Fazendas , Metais Pesados/análise , Esgotos , Solo , Poluentes do Solo/análise
3.
Environ Monit Assess ; 194(2): 69, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34994867

RESUMO

An investigation of water quality and heavy metal distribution in the groundwater samples collected from the vicinity of Narora Atomic Power Station (NAPS), Narora, India, was conducted for the metals including Cu, Zn, Ni, Co, Cd, Pb, and Fe. A total of 16 water quality parameters were measured for all the groundwater samples, and TDS, TH, Mg2+, Ca2+, F-, and turbidity were found to be on the higher side in comparison to the prescribed limits of Indian standards. Geometrical mean concentrations for these heavy metals were found to be 0.049, 0.213, 0.23, 0.135, 0.017, 0.061, and BDL for Cu, Fe, Zn, Pb, Cd, Co, and Ni, respectively. Pb and Cd were more than the permissible limits (0.01 mg/L for Pb and 0.003 for Cd) prescribed for safe drinking water while Cu and Fe were exceeding the permissible limits of 0.05 mg/L and 0.3 mg/L in 32% and 36% samples, respectively. Health risk assessment was done by calculating total hazard quotient (THQ), and the values for all the metals were below the threshold value of 1.0 beyond which they may pose a significant risk.


Assuntos
Água Subterrânea , Metais Pesados , Poluentes Químicos da Água , Monitoramento Ambiental , Índia , Metais Pesados/análise , Medição de Risco , Poluentes Químicos da Água/análise
4.
West Afr J Med ; 39(12): 1266-1272, 2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36583296

RESUMO

BACKGROUND: Trace elements are involved in oxidation reduction reactions in the body, including the central nervous system. The relationship between trace elements and psychiatric disorders have not been extensively investigated in the local population. We assessed the relationships between selected trace elements and schizophrenia. METHODS: A cross-sectional study of 70 newly diagnosed participants with schizophrenia, mean age = 33.6 ±10.7 years were recruited by simple random sampling. Sixty age-matched healthy subjects, mean age of 34.2 ± 7.9 years were recruited as control. Plasma Zn, Cu, Mn and Se were measured using atomic absorption spectrophotometer while toe nail Zn, Cu, Mn and Se were measured using inductively coupled plasma optical emission spectroscopy in both participants and controls. Illness severity was assessed using PANSS score. RESULTS: Mean plasma Zn, Cu and Mn were significantly lower in patients with schizophrenia than in control (p<0.001) while mean concentration of plasma Se was significantly higher in patients with schizophrenia than in control (p<0.001). Mean concentration of toenail Zn, Cu and Mn were significantly lower among schizophrenic group than in control group (p<0.001), however, mean toe nail Se level was similar in schizophrenic and control groups. In logistic regression, low plasma levels of Zn (Odds Ratio = 2.296, p<0.001), Cu (p<0.001), Mn (p<0.001) and Se (p<0.001) were independently associated with schizophrenia. There was no significant relationship between plasma Zn, Cu, Mn and Se and severity of illness using PANSS score. CONCLUSION: There is a possibility that low levels of Zn, Cu and Mn are involved in the aetiopathogenesis and progression of schizophrenia.


CONTEXTE: Les oligo-éléments participent aux réactions d'oxydoréduction dans l'organisme, y compris dans le système nerveux central. La relation entre les oligo-éléments et les troubles psychiatriques n'a pas été étudiée de façon approfondie dans la population locale. Nous avons évalué les relations entre certains oligo-éléments et la schizophrénie. MÉTHODES: Une étude transversale a été menée auprès de 70 participants atteints de schizophrénie, dont l'âge moyen était de 33,6 ± 10,7 ans, recrutés par échantillonnage aléatoire simple. Soixante sujets sains appariés selon l'âge, âgés en moyenne de 34,2 ± 7,9 ans, ont été recrutés comme témoins. Le Zn, le Cu, le Mn et le Se du plasma ont été mesurés à l'aide d'un spectrophotomètre d'absorption atomique, tandis que le Zn, le Cu, le Mn et le Se des ongles des orteils ont été mesurés à l'aide d'une spectroscopie d'émission optique à plasma à couplage inductif chez les participants et les témoins. La gravité de la maladie a été évaluée à l'aide du score PANSS. RÉSULTATS: La concentration plasmatique moyenne de Zn, Cu et Mn était significativement plus faible chez les patients atteints de schizophrénie que chez les témoins (p<0,001), tandis que la concentration moyenne de Se était significativement plus élevée chez les patients atteints de schizophrénie que chez les témoins (p<0,001). La concentration moyenne de Zn, Cu et Mn étaient significativement plus faibles dans le groupe schizophrène que dans le groupe témoin (p<0,001), cependant, le niveau moyen de Se dans les ongles des orteils était similaire dans les groupes schizophrènes et témoins. Dans la régression logistique, de faibles niveaux plasmatiques de Zn (Odds Ratio = 2,296, p<0,001), Cu (p<0,001), Mn (p<0,001) et Se (p<0,001) étaient indépendamment associés à la schizophrénie. Il n'y avait pas de relation significative entre le Zn, Cu, Mn et Se plasmatiques et la gravité de la maladie selon le score PANSS. CONCLUSION: Il est possible que de faibles niveaux de Zn, Cu et Mn soient impliqués dans l'étiopathogénie et la progression de la schizophrénie. Mots clés: Spectroscopie d'absorption atomique, spectroscopie d'émission optique du plasma à couplage inductif, score PANSS (Positive and Negative Syndrome Scale), schizophrénie, oligo-éléments.


Assuntos
Esquizofrenia , Oligoelementos , Humanos , Adulto , Adulto Jovem , Esquizofrenia/diagnóstico , Estudos Transversais , Nigéria
5.
Waste Manag Res ; 39(2): 242-249, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32564701

RESUMO

In this paper, we report leaching of precious and scattered metals such as gold (Au), copper (Cu), nickel (Ni), zinc (Zn), iron (Fe), and lead (Pb) from printed circuit boards of scrap mobile phones by hydrometallurgical process using inorganic acid, organic acid and base. The amount of metals leached by different leachants are quantified using atomic absorption spectroscopy. Among various inorganic acids, aqua regia (mixture of nitric acid (HNO3) and hydrochloric acid) is found to be the strongest leachant for most of the metals such as Zn (2.04 wt %), Fe (17.90 wt %), Ni (0.66 wt %), Pb (5.86 wt %) and Au (0.04 wt %). The basic leachant, ammonium thiosulphate is found to be very effective in leaching of Au (0.03125 wt %). The dissolution of Cu in HNO3 gives the highest amount of Cu in the solvent, that is, ∼ 7.52 wt %. The metallic phases present in the electronic waste before and after leaching are identified by X-ray diffraction analysis. The microscopic structure has been studied using a scanning electron microscope which depicts erosion of the structure after leaching.


Assuntos
Telefone Celular , Resíduo Eletrônico , Cobre , Resíduo Eletrônico/análise , Ouro , Compostos Orgânicos
6.
Environ Res ; 187: 109669, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32445943

RESUMO

Two new ionic imprinted hybrid polymers (IIHP) and their corresponding non imprinted hybrid polymers (NIHP) were synthesized. The prepared IIHP was highly selective to Cd2+. To prepare the IIHP, 1-vinylimidazole (VIN) was used as the functional monomer, (3-mercaptopropyl) trimethoxysilane (MP) or (3-aminopropyl) trimethoxysilane (AMP) was used as the functional organosilane, trimethylolpropane (TRIM) was used as the crosslinking agent, AIBN was used as a radical initiator and TEOS was used as a functional precursor. The functional monomer was selected considering calculations based on the density functional theory (DFT). The fabricated materials were characterized via field emission gun scanning electron microscopy (FEG-SEM), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDX) and thermogravimetric analysis (TGA). The maximum adsorption capacity of Cd2+ was achieved at a pH of 7.2 in the tris-HCl medium. The adsorption test indicated that the reaction followed pseudo second order kinetics, and the equilibrium sorption data fitted well into the Langmuir isotherm model. The relative selectivity coefficients of polymers IIHP-VIN-AMP and IIHP-VIN-MP, as evaluated in binary mixtures of Cd2+ and interferent cations (Pb2+, Zn2+, Hg2+, Cu2+, Ni2+, Ca2+, Mg2+, and Na+) at different molar ratios, were greater than one due to the presence of specific recognition sites for Cd2+ ions. Moreover, the selective materials exhibited a high reusability and reproducibility in the context of Cd2+ adsorption. These adsorbent materials, specifically IIHP-VIN-MP, exhibited a % removal efficiency of more than 90% for the Cd2+ in river water samples.


Assuntos
Polímeros , Poluentes Químicos da Água , Adsorção , Cádmio , Concentração de Íons de Hidrogênio , Íons , Cinética , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Mikrochim Acta ; 187(11): 602, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33034749

RESUMO

A new class of polymeric sorbents based on deep eutectic solvents (DESs) is introduced. These materials are obtained from simple and inexpensive precursors via an energy-efficient process. The primary benefit of these sorbents is that they possess the unique characteristics of DESs and porous materials simultaneously. Moreover, the possibility of tailoring deep eutectic solvents allows designing a specific polymer for a desired analyte, based on its physical and chemical properties. In this work, the deep eutectic solvent of tetrabutylammonium bromide and acrylic acid (1:2 molar ratio) was prepared and then polymerized under solventless condition. The synthesized polymer was characterized by FT-IR spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), and Brunauer, Emmett and Teller analysis (BET) to evaluate the properties of the sorbent. The poly (TBAB-2AA DES) was applied as a selective sorbent for preconcentration of lead from food and water samples prior to its quantification by flame atomic absorption spectroscopy (FAAS). Variable factors affecting the extraction were optimized, and under the optimum conditions, the calibration plot was linear in the range 5.0-250.0 µg L-1. The relative standard deviation was (for n = 5) (RSD) < 3%. The limit of detection (LOD) and the enhancement factor were found to be 2.0 µg L-1 and 50, respectively. Finally, the accuracy of the method was assessed by comparison of the results with those obtained by direct determination of lead using inductively coupled plasma mass spectrometry (ICP-MS) and spiked real samples. The obtained recoveries were between 92 and 106%. Graphical abstract.


Assuntos
Solventes Eutéticos Profundos/química , Análise de Alimentos , Chumbo/química , Extração em Fase Sólida , Verduras/química , Água/química , Contaminação de Alimentos , Limite de Detecção , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química , Difração de Raios X
8.
Mikrochim Acta ; 187(1): 91, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31897821

RESUMO

This work describes an aptamer based method for highly sensitive determination of Hg(II). A Hg(II)-binding ssDNA aptamer was linked to silica-coated magnetic nanoparticles (magNPs). Then, a conjugate composed of graphene and CdS quantum dots (Gr-CdS) was linked to the complementary ssDNA. On mixing the two components, a duplex of type magNP-dsNNA-Gr/CdS is generated. If Hg(II) is added, it wills capturing the aptamer, and this leads to the release of Gr/CdS because of the formation of a stable thymine-Hg2+-thymine link. External magnetic force is used to remove the remaining complex. The released graphene-CdS is decomposed by HNO3 and injected into a graphite furnace AAS. The detectable amount of Cd is proportional to the concentration of Hg(II) in the sample. Under the optimal conditions, the method has a linear response in the 2.50 aM to 0.25 nM Hg(II) concentration range, and the detection limit is as low as 7.6 aM (at S/N = 3). It has high selectivity for Hg(II) over other metal ions. Graphical abstract.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , Compostos de Cádmio/análise , Magnetismo , Mercúrio/análise , Nanopartículas/química , Pontos Quânticos/química , Sulfetos/análise , Compostos de Cádmio/química , DNA de Cadeia Simples/metabolismo , Grafite , Limite de Detecção , Mercúrio/metabolismo , Métodos , Dióxido de Silício , Sulfetos/química
9.
Molecules ; 25(20)2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33086622

RESUMO

Microextraction procedures for the separation of Pb(II) from water and food samples extracts were developed. A deep eutectic solvent composed of α-benzoin oxime and iron(III) chloride dissolved in phenol was applied as a phase separator support. In addition, this deep eutectic mixture worked as an efficient extractor of Pb(II). The developed microextraction process showed a high ability to tolerate the common coexisting ions in the real samples. The optimum conditions for quantitative recoveries of Pb(II) from aqueous extracts were at pH 2.0, conducted by adding 150 µL from the deep eutectic solvent. The quantitative recoveries were obtained with various initial sample volumes up to 30 mL. Limits of detection and limits of quantification of 0.008 and 0.025 µg L-1 were achieved with a relative standard deviation (RSD%) of 2.9, which indicates the accuracy and sensitivity of the developed procedure. Recoveries from the reference materials, including TMDA 64.2, TMDA 53.3, and NCSDC-73349, were 100%, 97%, and 102%, respectively. Real samples, such as tap, lake, and river water, as well as food samples, including salted peanuts, chickpeas, roasted yellow corn, pistachios, and almonds, were successfully applied for Pb(II) analysis by atomic absorption spectroscopy (AAS) after applying the developed deep eutectic solvent-based microextraction procedures.


Assuntos
Compostos Férricos/isolamento & purificação , Chumbo/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Água/química , Animais , Compostos Férricos/química , Contaminação de Alimentos , Humanos , Chumbo/toxicidade , Limite de Detecção , Microextração em Fase Líquida , Leite/química , Espectrofotometria Atômica , Poluentes Químicos da Água/química
10.
Prep Biochem Biotechnol ; 50(8): 842-848, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32302260

RESUMO

Chromium, ranking the second most among toxic heavy metal pollutants in the world, causing respiratory, cardiovascular and renal problems in human beings is under study herein. We examined the biological remediation of the carcinogenic Cr (VI) polluted soils by indigenous yeast isolates. The total element analysis of the treated sample was determined by Energy Dispersion X-ray Micro Analysis (EDXMA). The sample under study was observed to have a high concentration of 458.29 mgKg-1 Cr (VI), determined by Atomic Absorption Spectroscopy (AAS) and DPC analysis. The most tolerant isolate designated as CSR was used for in vitro and ex-situ bioremediation studies of Cr (VI). The isolate achieved significant bioremediation of 86% in vitro and 75.12% in ex-situ method. The optimal conditions for in vitro bioremediation were found to be 28 °C and a pH of 6. The ITS1, 5.8S rRNA and D1, D2 domain of LSU rRNA gene characterization of the isolate CSR illustrated that it belongs to Ustilago genera. The isolate was deposited in NCBI GenBank as Ustilago sp. CSR (KY284846). Although, Ustilago is generally a pathogenic fungus, our study opens up the scope of using Ustilago spp. for bioremediation of the carcinogenic heavy metal Chromium.


Assuntos
Carcinógenos/isolamento & purificação , Cromo/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Leveduras/metabolismo , Biodegradação Ambiental , Carcinógenos/metabolismo , Cromo/metabolismo , Humanos , Microbiologia do Solo , Poluentes do Solo/metabolismo , Leveduras/isolamento & purificação
11.
Int J Legal Med ; 133(5): 1485-1496, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30610447

RESUMO

The Agatston score (AS) is the gold standard CT calcium scoring method in clinical practice. However, the AS is an indirect method of determining calcium amount, whereas atomic absorption spectroscopy (AAS) can directly measure the calcium amount. Our primary aim was to investigate the association between the AS and the coronary calcium amount measured by AAS. Furthermore, we compared our outcome to the macroscopic and histological coronary calcification and stenosis assessment, thus allowing us to infer a clinical coronary artery status based on post-mortem findings. Deceased individuals were examined with a 64-slice multidetector CT scanner, and the AS was determined. At autopsy, the degree of CAC and stenosis was determined, and the coronary arteries were excised and weighed. The coronary arteries were decalcified in a solution that was examined using AAS to measure the calcium amount. The degree of CAC and stenosis was also assessed by a histological examination. One hundred thirty-two coronary arteries were examined, and AS was highly correlated to the coronary calcium amount, measured by AAS, (r2 = 0.72, Pearson 0.85, p < 0.0001). In cases with AS 0, AAS measurements showed zero or very low calcium amounts. AS was also correlated to macroscopic and histological calcification assessments (Spearman's rho 0.68, p < 0.0001, Spearman's rho 0.82, p < 0.0001). Furthermore, an underestimation of subclinical atherosclerosis was seen and AS 0 could not rule out stenosis.


Assuntos
Cálcio/análise , Estenose Coronária/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Calcificação Vascular/diagnóstico por imagem , Autopsia , Estenose Coronária/patologia , Vasos Coronários/patologia , Correlação de Dados , Feminino , Humanos , Masculino , Tomografia Computadorizada Multidetectores , Espectrofotometria Atômica , Calcificação Vascular/patologia
12.
Mikrochim Acta ; 186(10): 666, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31482367

RESUMO

A MWCNT@MoSe2 nanorod hybrid material was synthesized by a hydrothermal method and used as an adsorbent for trace levels of Pb(II) and Cu(II). The material was characterized by Raman spectroscopy, XRD, SEM, SEM-EDX, SEM-mapping and BET methods. The hybrid material is demonstrated to be a viable sorbent for ultrasound-assisted solid phase extraction of Pb(II) and Cu(II) at pH 5.5. Following desorption with 3 M HNO3, the two elements were quantified by FAAS. Key parameters affecting the extraction efficiency, including eluent conditions, amount of adsorbent, sample volume were optimized. No significant interference by other ions is observed. The accuracy of the method was evaluated by the analysis of the certified reference materials TMDA-53.3 (lake water) and SPS-WW2 (waste water level 2). The recoveries were in good agreement with certified values. The method was successfully applied to the extraction/preconcentration of Pb(II) and Cu(II) in different real samples. Graphical abstract A hybrid material of type MWCNT@MoSe2 was synthesized, characterized, and used as adsorbent for Pb(II) and Cu(II). Key parameters affecting the extraction efficiency, including eluent conditions, amount of adsorbent, sample volume were optimized. The method was applied to the extraction of analytes in water samples.

13.
Int J Phytoremediation ; 21(12): 1254-1262, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31134813

RESUMO

Calotropis procera is a perennial big shrub that has the potential to accumulate high concentrations of heavy metals. Metal sequestration in old organs has been considered as a mechanism for plant survival in polluted soils. The aim of the present study was to assess the role of the old leaves as a sink for HMs accumulation in C. procera. Two instruments were used: atomic absorption spectroscopy (AAS) and X-ray fluorescence (XRF) microscopy. Soil and plant samples were collected from around one of the worst congested traffic areas in the United Arab Emirates (UAE). Samples from roots, stem, and green and old leaves were prepared and analyzed by both instruments. Calotropis procera was able to concentrate Fe, Mn, Sr, and Zn in the roots, but their translocation to stem and green leaves was low. Old leaves had greater ability to accumulate significantly higher concentrations of different metals, especially Fe and Sr, than other parts of the plants, indicating that C. procera uses these metabolically less-active leaves as sinks for heavy metals. Fe and Sr attained higher bioconcentration and accumulation values, compared to Zn and Mn. There were significant positive correlations between XRF and AAS for all elements in the different organs.


Assuntos
Calotropis , Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Monitoramento Ambiental , Folhas de Planta
14.
Molecules ; 24(7)2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30939866

RESUMO

Mercury (Hg) is a well-known toxic element, diffused in the environment, especially in the Mediterranean Sea which is rich in cinnabar deposits. Mercury bioaccumulation in fish is of great concern, especially for top-level aquatic predators (e.g., shark, tuna, swordfish) and above all for species of large human consumption and high nutritional value. This work aimed to determine Hg concentrations in farmed and wild Atlantic Bluefin tuna (Thunnus thynnus) caught in the Mediterranean area in order to evaluate the level of Hg bioaccumulation. selenium (Se) content was also determined, since this element is an antagonist of mercury toxicity. Mercury and Se were analysed by atomic absorption spectrometry after microwave digestion of the samples. Hg content in farmed tuna was below the legal limit (1 mg/kg, wet weight, w.w.) for all specimens (0.6 ± 0.2 mg/kg), whereas the wild ones had a content over the limit (1.7 ± 0.6 mg/kg); Se concentration was higher in farmed specimens (1.1 ± 0.9 mg/kg) compared to wild ones (0.6 ± 0.3 mg/kg). A safe seafood could show a Se/Hg ratio >1 and a health benefit value (HBVSe) > 0: farmed tuna had higher values than the wild specimens (Se/Hg 5.48 vs. 1.32; HBVSe 11.16 vs. 0.29). These results demonstrate that for Hg, there is a better risk/benefit ratio in farmed T. thynnus. making it safer than wild tuna.


Assuntos
Fazendas , Contaminação de Alimentos/análise , Mercúrio/análise , Músculos/metabolismo , Atum/metabolismo , Animais , Mar Mediterrâneo
15.
Int J Phytoremediation ; 20(6): 593-598, 2018 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-29688049

RESUMO

Excess of copper ion (>2 mg/L) in water is toxic to human beings and the ecosystem. Various water treatment technologies for copper remediation have been investigated in the past. Along with industrial effluents, Bordeaux mixture is also a noteworthy copper contamination source in the agricultural ecosystem. In our study, the biosorbent efficiency of dried orange peel was investigated through an environment-friendly process for the removal of cupric ions. Effects of pH, adsorbate concentration, adsorbent dosage, and temperature for the removal of Cu (II) were studied. Slightly acidic environment (pH = 6) was found to be optimum for removal of copper. The equilibrium data were well fitted with the Langmuir and Freundlich isotherms. The surface morphology of the adsorbent was studied using scanning electron microscope. Crystalline nonhomogenous surface was observed after copper adsorption. Desorption study indicated that 0.1N H2SO4 is the best eluent for the removal of adsorbed copper from the powdered dried orange peel.


Assuntos
Citrus sinensis , Poluentes Químicos da Água/química , Purificação da Água , Adsorção , Biodegradação Ambiental , Cobre/química , Ecossistema , Concentração de Íons de Hidrogênio , Cinética , Água
16.
Women Health ; 58(7): 822-833, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-28682191

RESUMO

Pregnant and nursing women are at higher risk of zinc deficiency which can have detrimental consequences on health. We assessed blood zinc levels in 72 nursing women from the West Bank of Palestine and investigated the association between sociodemographic variables and blood zinc levels. Blood samples were analyzed for their zinc contents using graphite furnace atomic absorption spectrophotometry. Blood and data collection were performed between July and December 2016. The median blood zinc level was 4.53 mg/L (interquartile range of 0.38 mg/L). In unadjusted analyses, blood zinc levels were higher in nursing women who lived in cities (p-value <.001), had higher household income (p-value <.001), whose husbands had a white collar job (p-value <.05), were nonsmokers (p-value <.05), did not use hair dyes (p-value <.05), and consumed energy beverages (p-value <.001). Multiple linear analysis showed that living in cities and consuming energy beverages remained significantly associated with higher blood zinc levels (p-value <.05). Blood zinc levels were in the range previously reported for similar non-malnourished populations. Nursing women living in cities and those consuming energy beverages tended to have higher blood zinc levels. Urbanized lifestyle might have enhanced blood zinc levels in nursing women.


Assuntos
Estilo de Vida , Características de Residência , Espectrofotometria Atômica/métodos , Zinco/sangue , Adulto , Estudos Transversais , Feminino , Humanos , Oriente Médio , Gravidez/sangue , Gravidez/fisiologia , População Rural , Fatores Socioeconômicos , Inquéritos e Questionários , População Urbana
17.
J Hepatol ; 67(3): 535-542, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28483679

RESUMO

BACKGROUND & AIMS: Liver iron accumulates in various chronic liver diseases where it is an independent factor for survival and carcinogenesis. We tested a novel room-temperature susceptometer (RTS) to non-invasively assess liver iron concentration (LIC). METHODS: Two hundred and sixty-four patients with or without signs of iron overload or liver disease were prospectively enrolled. Thirty-five patients underwent liver biopsy with semiquantitative iron determination (Prussian Blue staining), atomic absorption spectroscopy (AAS, n=33), or magnetic resonance imaging (MRI, n=15). RESULTS: In vitro studies demonstrated a highly linear (r2=0.998) association between RTS-signal and iron concentration, with a detection limit of 0.3mM. Using an optimized algorithm, accounting for the skin-to-liver capsule distance, valid measurements could be obtained in 84% of cases. LIC-RTS showed a significant correlation with LIC-AAS (r=0.74, p<0.001), LIC-MRI (r=0.64, p<0.001) and hepatocellular iron (r=0.58, p<0.01), but not with macrophage iron (r=0.32, p=0.30). Normal LIC-RTS was 1.4mg/g dry weight. Besides hereditary and transfusional iron overload, LIC-RTS was also significantly elevated in patients with alcoholic liver disease. The areas under the receiver operating characteristic curve (AUROC) for grade 1, 2 and 3 hepatocellular iron overload were 0.72, 0.89 and 0.97, respectively, with cut-off values of 2.0, 4.0 and 5.0mg/g dry weight. Notably, the positive and negative predictive values, sensitivity, specificity and accuracy of severe hepatic iron overload (HIO) (grade ≥2) detection, were equal to AAS and superior to all serum iron markers. Depletion of hepatic iron could be efficiently monitored upon phlebotomy. CONCLUSIONS: RTS allows for the rapid and non-invasive measurement of LIC. In comparison to MRI, it could be a cost-effective bedside method for LIC screening. Lay summary: Novel room-temperature susceptometer (RTS) allows for the rapid, sensitive, and non-invasive measurement of liver iron concentration. In comparison to MRI, it could be a cost-effective bedside method for liver iron concentration screening.


Assuntos
Ferro/análise , Fígado/química , Adulto , Idoso , Feminino , Humanos , Ferro/metabolismo , Fígado/metabolismo , Fígado/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Espectrofotometria Atômica , Temperatura
18.
Chemistry ; 23(8): 1869-1880, 2017 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-27865002

RESUMO

Gold complexes with N-heterocyclic carbene (NHC) ligands represent a promising class of metallodrugs for the treatment of cancer or infectious diseases. In this report, the synthesis and the biological evaluation of halogen-containing NHC-AuI -Cl complexes are described. The complexes 1 and 5 a-5 f displayed good cytotoxic activity against tumor cells, and cellular uptake studies suggested that an intact Au-NHC fragment is essential for the accumulation of high amounts of both the metal and the NHC ligand. However, the bioavailability was negatively affected by serum components of the cell culture media and was influenced by likely transformations of the complex. One example (5 d) efficiently induced apoptosis in vincristine- and daunorubicin-resistant P-glycoprotein overexpressing Nalm-6 leukemia cells. Cellular uptake studies with this compound showed that both the wild-type and resistant Nalm-6 cells accumulated comparable amounts of gold, indicating that the gold drug was not excreted by P-glycoprotein or other efflux transporters. The effective inhibition of mammalian and bacterial thioredoxin reductases (TrxR) was confirmed for all of the gold complexes. Antibacterial screening of the gold complexes showed a particularly high activity against Gram-positive strains, reflecting their high dependence on an intact Trx/TrxR system. This result is of particular interest as the inhibition of bacterial TrxR represents a relatively little explored mechanism of new anti-infectives.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/química , Proteínas de Bactérias/antagonistas & inibidores , Complexos de Coordenação/química , Ouro/química , Bactérias Gram-Positivas/efeitos dos fármacos , Tiorredoxina Dissulfeto Redutase/antagonistas & inibidores , Antibacterianos/síntese química , Antibacterianos/química , Antineoplásicos/síntese química , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/metabolismo , Complexos de Coordenação/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Compostos Heterocíclicos/química , Humanos , Metano/análogos & derivados , Metano/química , Testes de Sensibilidade Microbiana , Tiorredoxina Dissulfeto Redutase/metabolismo
19.
Part Fibre Toxicol ; 14(1): 12, 2017 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-28410606

RESUMO

BACKGROUND: Previous work has demonstrated size, surface charge and skin barrier dependent penetration of nanoparticles into the viable layers of mouse skin. The goal of this work was to characterize the tissue distribution and mechanism of transport of nanoparticles beyond skin, with and without Ultraviolet Radiation (UVR) induced skin barrier disruption. Atomic absorption spectroscopy (AAS), flow cytometry and confocal microscopy were used to examine the effect of UVR dose (180 and 360 mJ/cm2 UVB) on the skin penetration and systemic distribution of quantum dot (QD) nanoparticles topically applied at different time-points post UVR using a hairless C57BL/6 mouse model. RESULTS: Results indicate that QDs can penetrate mouse skin, regardless of UVR exposure, as evidenced by the increased cadmium in the local lymph nodes of all QD treated mice. The average % recovery for all treatment groups was 69.68% with ~66.84% of the applied dose recovered from the skin (both epicutaneous and intracutaneous). An average of 0.024% of the applied dose was recovered from the lymph nodes across various treatment groups. When QDs are applied 4 days post UV irradiation, at the peak of the skin barrier defect and LC migration to the local lymph node, there is an increased cellular presence of QD in the lymph node; however, AAS analysis of local lymph nodes display no difference in cadmium levels due to UVR treatment. CONCLUSIONS: Our data suggests that Langerhans cells (LCs) can engulf QDs in skin, but transport to the lymph node may occur by both cellular (dendritic and macrophage) and non-cellular mechanisms. It is interesting that these specific nanoparticles were retained in skin similarly regardless of UVR barrier disruption, but the observed skin immune cell interaction with nanoparticles suggest a potential for immunomodulation, which we are currently examining in a murine model of skin allergy.


Assuntos
Pontos Quânticos/metabolismo , Absorção Cutânea/efeitos da radiação , Pele/metabolismo , Raios Ultravioleta/efeitos adversos , Administração Cutânea , Animais , Transporte Biológico , Movimento Celular , Células de Langerhans/efeitos dos fármacos , Células de Langerhans/metabolismo , Linfonodos/efeitos dos fármacos , Linfonodos/metabolismo , Camundongos Pelados , Camundongos Endogâmicos C57BL , Doses de Radiação , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Absorção Cutânea/efeitos dos fármacos , Fatores de Tempo , Distribuição Tecidual
20.
J Clin Lab Anal ; 31(6)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28205254

RESUMO

BACKGROUND: The homeostasis of essential trace elements such as selenium and manganese may be altered in patients with severe diseases of various etiologies (trauma brain injuries, tumors, leukemias, lymphomas, neurological diseases). METHODS: Concentration of manganese and selenium were determined in cerebrospinal fluid by electrothermal atomic absorption spectrometry in 50 hospitalized children with various clinical ethiologies including oncological, neurological, and brain related diseases. RESULTS: The concentrations of manganese in cerebrospinal fluid of children were 0.97±0.67 µg/L. The concentrations of selenium were 13.3±3.5 µg/L. The concentrations were similar as published in adults. The values did not correlated with the age, gender and severity of the disease. CONCLUSION: We evaluated values of selenium and manganese in cerebrospinal fluid of seriously diseased children.


Assuntos
Manganês/líquido cefalorraquidiano , Selênio/líquido cefalorraquidiano , Adolescente , Encefalopatias/líquido cefalorraquidiano , Criança , Pré-Escolar , Estado Terminal , Feminino , Humanos , Lactente , Limite de Detecção , Modelos Lineares , Masculino , Neoplasias/líquido cefalorraquidiano , Espectrofotometria Atômica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA