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1.
Toxicol Mech Methods ; 29(1): 26-34, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30064281

RESUMO

Previous studies have brought to light the toxic effect of cerium chloride (CeCl3) but very little is known about the oxidative brain injury caused by this metal. Medical plants have a well-recognized role in the management of damage caused by pollutants such as CeCl3. Syzygium aromaticum, a potent natural source of bioactive compounds and rich in secondary metabolites, has a broad range of biological functions. The aim of this study is to investigate the capacity of Syzygium aromaticum ethanol extract (ESA) to improve the adverse effects of CeCl3 in the brain tissue. Adult mice were exposed to CeCl3 (20 mg/kg body weight [BW]), with or without ESA, for 60 days. We investigate mice's behavior, damages of cholinergic system and oxidative stress parameters in mice brain. In the present study, in vitro test confirmed that ESA has antioxidant capacity attributed to the presence of flavonoids, polyphenols, and tannins contents. In vivo study showed that CeCl3 caused brain injuries manifested in memory impairment, increase in acetylcholinesterase activity, oxidative stress biomarkers (lipid, proteins, enzymatic and non-enzymatic antioxidant systems), and histopathological alteration in brain tissue. Addition of ESA repaired memory impairment, decreased acetylcholinesterase activity, restored oxidative state, and prevented histopathological alteration. In conclusion, the experimental results showed the protective effects of ethanol extract of Syzygium aromaticum against cerium-induced brain damage.


Assuntos
Encéfalo/efeitos dos fármacos , Cério/toxicidade , Fármacos Neuroprotetores/uso terapêutico , Síndromes Neurotóxicas/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Syzygium/química , Animais , Antioxidantes/metabolismo , Encéfalo/metabolismo , Camundongos , Fármacos Neuroprotetores/isolamento & purificação , Síndromes Neurotóxicas/etiologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação
2.
Biochem Biophys Res Commun ; 482(4): 916-921, 2017 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-27890616

RESUMO

DNA adopts different conformation not only because of novel base pairs but also while interacting with inorganic or organic compounds. Self-assembled branched DNA (bDNA) structures or DNA origami that change conformation in response to environmental cues hold great promises in sensing and actuation at the nanoscale. Recently, the B-Z transition in DNA is being explored to design various nanomechanical devices. In this communication we have demonstrated that Cerium chloride binds to the phosphate backbone of self-assembled bDNA structure and induce B-to-Z transition at physiological concentration. The mechanism of controlled conversion from right-handed to left-handed has been assayed by various dye binding studies using CD and fluorescence spectroscopy. Three different bDNA structures have been identified to display B-Z transition. This approach provides a rapid and reversible means to change bDNA conformation, which can be used for dynamic and progressive control at the nanoscale.


Assuntos
Cério/química , DNA de Forma B/química , DNA Forma Z/química , Nanoestruturas/química , Sítios de Ligação , Dicroísmo Circular , Nanotecnologia/métodos , Conformação de Ácido Nucleico , Desnaturação de Ácido Nucleico , Espectrometria de Fluorescência
3.
Environ Toxicol ; 30(4): 452-60, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24338979

RESUMO

Bombyx mori is an important economic animal for silk production. However, it is liable to be infected by organophosphorus pesticide that can contaminate its food and growing environment. It has been known that organophosphorus pesticide including phoxim exposure may damage the digestive systems, produce oxidative stress and neurotoxicity in silkworm B. mori, whereas cerium treatment has been demonstrated to relieve phoxim-induced toxicity in B. mori. However, very little is known about the molecular mechanisms of midgut injury due to phoxim exposure and B. mori protection after cerium pretreatment. The aim of this study was to evaluate the midgut damage and its molecular mechanisms, and the protective role of cerium in B. mori following exposure to phoxim. The results showed that phoxim exposure led to severe midgut damages and oxidative stress; whereas cerium relieved midgut damage and oxidative stress caused by phoxim in B. mori. Furthermore, digital gene expression suggested that phoxim exposure led to significant up-regulation of 94 genes and down-regulation of 52 genes. Of these genes, 52 genes were related with digestion and absorption, specifically, the significant alterations of esterase, lysozyme, amylase 48, and lipase expressions. Cerium pretreatment resulted in up-regulation of 116 genes, and down-regulation of 29 genes, importantly, esterase 48, lipase, lysozyme, and α-amylase were up-regulated. Treatment with Phoxim + CeCl3 resulted in 66 genes up-regulation and 39 genes down-regulation; specifically, levels of esterase 48, lipase, lysozyme, and α-amylase expression in the midgut of silkworms were significantly increased. Therefore, esterase 48, lipase, lysozyme, and α-amylase may be potential biomarkers of midgut toxicity caused by phoxim exposure. These findings may expand the application of rare earths in sericulture.


Assuntos
Cério/farmacologia , Inseticidas/toxicidade , Compostos Organotiofosforados/toxicidade , Animais , Bombyx , Regulação da Expressão Gênica/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Intestinos/patologia , Intestinos/ultraestrutura , Larva/efeitos dos fármacos , Larva/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real
4.
Environ Toxicol ; 30(9): 1102-11, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24616058

RESUMO

It is known that exposure to organophosphorus pesticides (OP) including phoxim can produce oxidative stress, neurotoxicity, and greatly attenuate cocooning rate in the silkworm, Bombyx mori. Cerium treatment has been demonstrated to relieve phoxim-induced toxicity in B. mori; however, very little is known about the molecular mechanisms of silk gland injury due to OP exposure and protection of gland damage due to cerium pretreatment. The aim of this study was to evaluate silk gland damage and its molecular mechanisms in phoxim-induced silkworm toxicity and the protective mechanisms of cerium following exposure to phoxim. The results showed that phoxim exposure resulted in severe gland damage, reductions in protein synthesis and the cocooning rate of silkworms. Cerium (Ce) attenuated gland damage caused by phoxim, promoted protein synthesis, increased the antioxidant capacity of the gland and increased the cocooning rate of B. mori. Furthermore, digital gene expression data suggested that phoxim exposure led to significant up-regulation of 714 genes and down-regulation of 120 genes. Of these genes, 122 were related to protein metabolism, specifically, the down-regulated Ser2, Ser3, Fib-L, P25, and CYP450. Ce pretreatment resulted in up-regulation of 162 genes, and down-regulation of 141 genes, importantly, Ser2, Ser3, Fib-L, P25, and CYP333B8 were up-regulated. Treatment with CeCl3 + phoxim resulted in higher levels of Fib-L, P25, Ser2, Ser3, CAT, TPx, and CYP333B8 expression in the silk gland of silkworms. These findings indicated that Ce increased cocooning rate via the promotion of silk protein synthesis-related gene expression in the gland under phoxim-induced toxicity. These findings may expand the application of rare earths in sericulture.


Assuntos
Bombyx/efeitos dos fármacos , Cério/farmacologia , Inseticidas/toxicidade , Compostos Organotiofosforados/toxicidade , Substâncias Protetoras/farmacologia , Seda/biossíntese , Animais , Antioxidantes/metabolismo , Peso Corporal/efeitos dos fármacos , Bombyx/metabolismo , Regulação para Baixo/efeitos dos fármacos , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
5.
Environ Toxicol ; 29(7): 837-46, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23139204

RESUMO

Numerous studies have demonstrated lanthanide (Ln) accumulation in the liver, and the corresponding damage; however, very little work has been done to evaluate the relationship between Ln-induced liver injury and its gene expression profile in mice. In this study, liver injury and gene-expressed profiles in male mice induced by oral administration of CeCl3 (2 mg/kg) via gavage for 90 consecutive days were investigated. The results showed that cerium accumulation, liver inflammation, and hepatocyte necrosis were observed. CeCl3 exposure significantly decreased the counts of white blood cells, lymphocyte, and platelet, the reticulocyte count (Ret) and neutrophilic granulocyte percentages as well as A/G ratio, whereas markedly increased the activities of alkaline phosphatase, lactate dehydrogenase, and cholinesterase, and the concentrations of triglycerides and total cholesterol. Furthermore, microarray results of liver showed that the differential expression of 675 known function genes involved in immune/inflammation response, apoptosis, metabolic process, cell cycle, cell proliferation, cytoskeleton, oxidative stress, signal transduction, transcription, translation, and transportation in CeCl3 exposed livers, respectively. Specifically, the significant downregulation of Nt5e led to inflammation, overexpressed Cyp4a12a and great suppression of Cdkn1a resulted in hepatocyte apoptosis, marked elevation of Cel, and Cyp7b1 expression caused the metabolic disorders in mouse liver after long-term CeCl3 exposure. Therefore, these genes may be in great relation to liver damages induced by exposure to CeCl3 .


Assuntos
Cério/toxicidade , Poluentes Ambientais/toxicidade , Fígado/efeitos dos fármacos , Animais , Apoptose/genética , Biomarcadores/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Fígado/metabolismo , Fígado/patologia , Testes de Função Hepática , Masculino , Camundongos Endogâmicos ICR , Estresse Oxidativo/efeitos dos fármacos , Transcriptoma
6.
Environ Toxicol ; 29(12): 1420-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23712967

RESUMO

It has been demonstrated that the organic damages of animals can be caused by exposure to lanthanide oxides or compounds. However, the molecular mechanism of CeCl3 -induced kidney injury remains unclear. In this study, the mechanism of nephric damage in mice induced by an intragastric administration of CeCl3 was investigated. The results showed that Ce(3+) was accumulated in the kidney, which in turn led to oxidative stress, severe nephric inflammation, and dysfunction in mice. Furthermore, CeCl3 activated nucleic factor κB, which in turn increased the expression levels of tumor necrosis factor α, macrophage migration inhibitory factor, interleukin-2, interleukin-4, interleukin-6, interleukin-8, interleukin-10, interleukin-18, interleukin-1ß, cross-reaction protein, transforming growth factor-ß, interferon-γ, and CYP1A1, while suppressed heat shock protein 70 expression. These findings implied that Ce(3+) -induced kidney injury of mice might be associated with oxidative stress, alteration of inflammatory cytokine expression, and reduction of detoxification of CeCl3 .


Assuntos
Cério/toxicidade , Citocinas/metabolismo , Rim/efeitos dos fármacos , Animais , Citocinas/genética , Expressão Gênica/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Interleucinas/metabolismo , Rim/metabolismo , Rim/patologia , Masculino , Camundongos Endogâmicos ICR , Nefrite/metabolismo , Estresse Oxidativo
7.
Anal Sci ; 38(2): 409-417, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35314988

RESUMO

X-ray diffraction measurements are performed on a 1 m (= mol kg-1) CeCl3 aqueous solution over a temperature range of 300-600 K and a pressure range of 0.1 MPa to 4 GPa. The experimental interference functions are analyzed by an empirical potential structure refinement (EPSR) modeling. The Ce3+ coordinates water molecules in a tricapped trigonal prism configuration under the ambient condition. The number of water molecules around Ce3+ changes from 8.8 at 0.1 MPa/300 K to 11.5 at 4 GPa/600 K. The number of water molecules around Cl- changes drastically from 10 under the ambient condition to 17 at 4 GPa/600 K. The tetrahedral-like network structure of water under the ambient condition is transformed toward a simple liquid-like packing in the GPa pressure range. The corresponding coordination number is increased from 4.3 in the ambient condition to 9.7 at 4 GPa/600 K. The Ce3+-Cl- association decreases with increasing pressure.

8.
Water Environ Res ; 92(3): 331-337, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31132196

RESUMO

High concentration of orthophosphate ion (OP) in anaerobically digested sludge can lead to struvite crystallization, deterioration of sludge dewaterability, and elevated mainstream OP loading through centrate recirculation. The Upper Occoquan Service Authority (UOSA) has observed seasonally high OP levels in its dewatering blend tank, which was found in this study to be a consequence of unwanted biological phosphorus accumulation during the intensified winter denitrification operation and the subsequent OP release in the course of anaerobic digestion. In order to control the nuisance struvite scaling issues, a bench study was conducted and cerium chloride (CeCl3 ) was dosed as an effective OP precipitant. The results of this study demonstrated that CeCl3 dosing showed higher OP removal efficiency than other commonly used OP precipitants. In addition, bench-scale simulations indicated sludge dewaterability improvements which were used to predict lower polymer and dewatering energy demands at the full scale. The economic analysis conducted in this case study showed that the seasonal dosing of CeCl3 at UOSA has the potential to provide a net annual saving of US $47,000. PRACTITIONER POINTS: Biological phosphorus accumulation during the intensified denitrification operation caused seasonally high sludge OP and struvite scaling issues at UOSA. CeCl3 was evaluated as an effective OP precipitant for struvite control and dewaterability improvement when aluminum and iron were determined to be unfavorable. Seasonal dosing of CeCl3 at UOSA projected a net annual saving of US $47,000.


Assuntos
Cério , Esgotos , Fosfatos , Estruvita , Eliminação de Resíduos Líquidos
9.
Appl Radiat Isot ; 163: 109211, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32561050

RESUMO

Different molar ratios of the cerium trichloride heptahydrate to isopropyl alcohol (1:2, 1:3 and 1:5) were studied to choose the optimum ratio, and studied the reaction temperature effect (80, 90 and 100 °C) to determine the optimum temperature for the preparation of poly nano cerium chloride (PNCC). The PNCC-1 was selected among the prepared PNCC batches based on the 99Mo sorption properties that confirms the feasibility of using it as a novel effective sorbent material. The structural properties and chemical composition were studied using different techniques and devices such as EDX, XRD, FESEM, FTIR, TGA, and DTA. The sorption capacity was found to be 450 ± 27 and 195 ± 11 mg/g PNCC-1 using the static and dynamic techniques, from 0.01 M NaOH to obtain about 55 and 75% 99mTc separation efficiency, respectively. The acceptability of the eluate 99mTc was investigated from the point of view of radiochemical, radionuclidic and chemical purity.

10.
J Hazard Mater ; 386: 121930, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31893556

RESUMO

In this work, sludge conditioning efficiency of cerium chloride (CeCl3) in combination with organic polymers was evaluated, the floc microstructure and extracellular polymeric substances (EPS) properties under flocculation conditioning were analyzed. The interaction mechanisms between EPS and Ce(III) were systematically investigated through two-dimension correlation spectroscopy, X-ray photoelectron spectroscopy, and confocal laser scanning microscopy. In addition, the adsorption and catalytic abilities of Ce-sludge based carbon (SBC) in tetracycline (TC) removal were evaluated. The results showed that CeCl3 conditioning performed well in improving sludge dewaterability, and CeCl3 and cationic polyacrylamide showed a synergistic effect in sludge conditioning. Contents of EPS decreased as the dosage of CeCl3 increased because of charge neutralization and complexation reactions. 2D-UV-FTIR heterospectral correlation spectroscopy analysis suggested the reaction activity of EPS to Ce(III) followed the order of humic acid > protein > polysaccharide. The decrease of α-helix content improved the hydrophobicity of proteins in EPS, which was responsible for sludge dewaterability improvement in CeCl3 conditioning. Besides, the SBC was prepared with CeCl3 conditioned sludge for treating water containing TC. Ce-SBC had a dual function of adsorption and Fenton-like activity. This work provides a sludge recycling process that coupled chemical conditioning to pyrolysis carbonization to prepare functional carbon-based materials.

11.
Chemosphere ; 239: 124769, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31526997

RESUMO

In this study, Cerium chloride-induced conformational changes of Bovine Liver Catalase (BLC) has been investigated by molecular docking and further supported by various biophysical techniques. The temporal change of catalytic activity of BLC has also been studied in presence of Ce(III) with different buffer solution in vitro at 25 °C. The differential binding of Ce(III) to BLC observed by simulation study was well supported by the differential regulation of BLC activity in different buffers. After 1 h of incubation with CeCl3, the reduction in activity of BLC was maximum in MOPS, HEPES and Tris buffer, whereas no change in activity was noticed in phosphate buffer. Isothermal Titration Calorimetric (ITC) study also supports the differential binding of Ce(III) to BLC in different buffers. Ce(III)-induced conformational transition in BLC was followed as a function of concentration. Nevertheless, with 24 h incubation of CeCl3 the activity of BLC was highest with higher molar concentration of CeCl3 suggesting the conformational stability of BLC in presence of Ce(III). The compromised activity of BLC in response to Ce(III) is due to the induced conformational change and the degree of change in secondary conformation of BLC was maximum in MOPS, HEPES and Tris and least in phosphate buffer. Therefore, the reduced activity of BLC is controlled by the direct interaction of Ce(III) in the active site of BLC in Tris buffer or indirect interaction of Ce(III) in the non-active site of BLC in MOPS and HEPES buffer.


Assuntos
Catalase/química , Catalase/metabolismo , Cério/química , Fígado/enzimologia , Animais , Soluções Tampão , Calorimetria , Domínio Catalítico , Bovinos , Cério/metabolismo , Cloretos/química , Simulação de Acoplamento Molecular , Conformação Proteica
12.
Environ Sci Pollut Res Int ; 25(20): 19555-19565, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29732511

RESUMO

Cerium chloride (CeCl3) is considered an environmental pollutant and a potent neurotoxic agent. Medicinal plants have many bioactive compounds that provide protection against damage caused by such pollutants. Curcuma longa is a bioactive compound-rich plant with very important antioxidant properties. To study the preventive and healing effects of Curcuma longa on cerium-damaged mouse brains, we intraperitoneally injected cerium chloride (CeCl3, 20 mg/kg BW) along with Curcuma longa extract, administrated by gavage (100 mg/kg BW), into mice for 60 days. We then examined mouse behavior, brain tissue damage, and brain oxidative stress parameters. Our results revealed a significant modification in the behavior of the CeCl3-treated mice. In addition, CeCl3 induced a significant increment in lipid peroxidation, carbonyl protein (PCO), and advanced oxidation protein product levels, as well as a significant reduction in superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities. Acetylcholinesterase (AChE) activity remarkably increased in the brain of CeCl3-treated mice. Histopathological observations confirmed these results. Curcuma longa attenuated CeCl3-induced oxidative stress and increased the activities of antioxidant enzymes. It also decreased AChE activity in the CeCl3-damaged mouse brain that was confirmed by histopathology. In conclusion, this study suggests that Curcuma longa has a neuroprotective effect against CeCl3-induced damage in the brain.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Cério/toxicidade , Poluentes Ambientais/toxicidade , Fármacos Neuroprotetores/uso terapêutico , Síndromes Neurotóxicas/prevenção & controle , Extratos Vegetais/uso terapêutico , Animais , Antioxidantes/metabolismo , Encéfalo/enzimologia , Curcuma , Masculino , Camundongos , Fármacos Neuroprotetores/isolamento & purificação , Síndromes Neurotóxicas/etiologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação
13.
Eur Arch Paediatr Dent ; 18(3): 163-169, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28343265

RESUMO

AIM: To evaluate the effect of 10% cerium chloride intervention on pre-demineralised human enamel subjected to cycles of de- and remineralisation. METHODS: This was an in vitro, comparative type study of 60 human enamel samples that were randomly divided into control and test groups. The samples were then subjected to a cycle of demineralisation followed by intervention with respective treatment solutions (control group: placebo solution; test: 10% cerium chloride) for 30 s under constant agitation and then to a 2nd cycle of demineralisation followed by remineralisation using artificial saliva. After the first and second cycles of demineralisation (4th and 8th day) and a cycle of remineralisation (22nd day), the samples were evaluated for fluorescence values using a quantitative light-induced fluorescence camera. The data was analysed using paired t test and ANOVA. RESULTS: Comparing the fluorescence values and mean difference of lesion area between the first cycle of demineralisation to the cycle of remineralisation and the second cycle of demineralisation to the cycle of remineralisation, the test group showed a statistically significant reduction in loss of fluorescence values and lesion area compared to the control group (p < 0.001). Mean fluorescence values and lesion area comparison between cycles of de- and remineralisation for control and test groups (inter-group comparison) showed a statistically significant difference (p < 0.001). CONCLUSIONS: Cerium chloride alone reduced demineralisation and improved remineralisation of artificial caries lesions in human enamel when subjected to pH cycling in vitro.


Assuntos
Cério/uso terapêutico , Cárie Dentária/tratamento farmacológico , Desmineralização do Dente/tratamento farmacológico , Remineralização Dentária/métodos , Cloretos/uso terapêutico , Esmalte Dentário/efeitos dos fármacos , Fluorescência , Humanos , Técnicas In Vitro
14.
Materials (Basel) ; 10(6)2017 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28772932

RESUMO

This study investigated the effect of cerium chloride (CeCl3) on cell migration and gene expression of human foreskin fibroblasts (HFF). HFF were exposed to three different CeCl3 solutions (1%, 5% and 10%, w/v %) for three different time durations (1, 5 and 10 min). 72 h after exposure to CeCl3, cell viability was assessed by MTT test. A scratch-wounded assay determined the cell migration and the width of the wound, measured at 24 h. Gene expression patterns for cyclins B1, D1 and E1 were analyzed by RT-PCR (p < 0.05, t-test). The viability proliferation increased at 1- and 5-min exposures for all CeCl3 concentrations, in contrast to no treatment (p < 0.05 at 24 h). No influence of CeCl3 was found after 10 min. The scratch assay showed increased cell migration up to 60% at 1 and 5 min after 24 h at 5% and 10%. Cyclin B1, D1 and E1 all showed upregulation, confirming an increase in cell proliferation. This study demonstrates that exposure time and concentration of CeCl3 may have a positive effect on fibroblast viability and migration. Application of CeCl3 may be beneficial as a cell-stimulating agent leading to therapeutic tissue fibrosis or more resistant tissue around teeth, when warranted, during different periodontal therapies.

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