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1.
Food Chem Toxicol ; 131: 110575, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31201899

RESUMO

Bisphenol A and its analogues belong to the class of endocrine disrupting chemicals, massively employed by industries to produce polycarbonate and epoxy resins, designed to be in direct contact with foodstuffs. Their leaching from the canned packaging into its content results in food contamination. This review aims at offering a country-specific overview of the occurrence of bisphenols in six main categories of foodstuff marketed in the EU, based on monitoring studies performed in the 27 EU countries for which data are available and prevalently published in the last five years. The general overview of the literature data shows that concentration values of BPs detected into foodstuff is lower in Northern Europe than Southern Europe. A probable daily intake was hypothesized for some countries to provide an EU population exposure assessment. The consumption of canned meat and vegetables is responsible of PDI values higher than those of other food categories. These data emphasize that food and beverage monitoring should deserve greater attention especially by European countries for which no studies are available and especially with regards to bisphenols other than BPA whose limits are not set by the European regulations and whose toxicity has not been fully established.


Assuntos
Compostos Benzidrílicos/análise , Disruptores Endócrinos/análise , Contaminação de Alimentos/análise , Fenóis/análise , Exposição Dietética , Europa (Continente) , Embalagem de Alimentos , Alimentos em Conserva/análise , Análise de Perigos e Pontos Críticos de Controle , Humanos
2.
Ecotoxicol Environ Saf ; 180: 412-419, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31108418

RESUMO

Estrogens play a role in the patho-physiology of the prostate. In the present work we studied the effects of nonylphenol (NP), a xenoestrogen, on human adenocarcinoma prostate cells (LNCaP). In order to understand molecular and cellular involvement, we observed the effects on cell cycle and we investigated the expression and the cellular localization of estrogen receptors and gene expression of cyclin D1, ki-67, c-myc, IL-8, IL-1ß. We performed the same experiments with 17ß-estradiol (E2), the most abundant estrogen circulating in nonpregnant humans in order to compare these two different substances. We demonstrated the ability of 1 × 10-10 M NP to induce proliferation of LNCaP, S-phase progression, increase of ERα expression and its translocation from the cytoplasm to the nucleus. Moreover, we observed an up-regulation of key target genes involved in cell cycle and inflammation process. Particularly, after NP treatment, IL-8 and IL-1ß mRNA levels are increased more than 50% indicating a major NP involvement in inflammation processes than E2. These data suggest the proliferative effects of NP on prostate adenocarcinoma cells and highlight some aspects of molecular pathways involved in prostate responses to NP.


Assuntos
Poluentes Ambientais/toxicidade , Estradiol/toxicidade , Receptor alfa de Estrogênio/metabolismo , Fenóis/toxicidade , Neoplasias da Próstata/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina D1/genética , Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-1beta/genética , Masculino , Neoplasias da Próstata/metabolismo
3.
J Exp Zool A Ecol Integr Physiol ; 331(6): 357-361, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31132000

RESUMO

A histological study was conducted in red mullet, Mullus barbatus, collected from two sites characterized by different anthropogenic impacts. The aim of the study was to assess sex-, size-, season- and site-related variation in gonadal macrophage aggregate (MA) size, number, and relative area. Gonadal MAs were most abundant in males than in females. The number of MA was significantly higher in males from the most impacted site in October, with larger individuals showing more MA than smaller ones. MAs were always found in ripe testes, whereas they occurred only in regressing ovaries. These preliminary findings suggest that the presence of ovarian MA in red mullet is most likely related to ovary regression after spawning, whereas the presence of testicular MA is not necessarily associated to gonad regression, and may vary with season, size, and water quality.


Assuntos
Macrófagos , Ovário/citologia , Perciformes/fisiologia , Testículo/citologia , Animais , Tamanho Corporal , Feminino , Masculino , Estações do Ano , Poluição da Água/efeitos adversos , Qualidade da Água
4.
Biomed Chromatogr ; 33(3): e4427, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30408212

RESUMO

A quick and inexpensive validated method, based on sample treatment by liquid-liquid microextraction followed by liquid chromatography (LC) coupled with ultraviolet tandem fluorescence detection is proposed for the determination of 15 multiclass pollutants both in serum and in saliva, as a simple and easy to draw matrix. The method was set up and validated according to European guidelines. The compounds of interest include some endocrine-disrupting chemicals (i.e. bisphenol A, bisphenol B, bisphenol E, bisphenol F, bisphenol AF, bisphenol A diglycidyl ether, bisphenol M, diethylhexyl phthalate, monoethylhexyl phthalate, triclosan and 4-nonylphenol), as well as other pollutants belonging to the class of volatile organic compounds (2-chlorophenol, 1,2 dichlorobenzene, 1,2,4,5-tetrachlorobenzene). The limits of quantifications ranged from 2.28 × 10-3 µg mL-1 (bisphenol A diglycidyl ether) to 6.29 µg mL-1 (diethylhexyl phthalate), while those of detection ranged from 0.068 × 10-3 µg mL-1 (bisphenol A diglycidyl ether) to 1.031 µg mL-1 (diethylhexyl phthalate). To test method suitability, it was applied to real saliva and serum samples of healthy human volunteers and was found to meet the demands of the laboratories handling simple and relatively inexpensive equipment for screening oriented at rapid and reliable contamination assessment of a population.


Assuntos
Cromatografia Líquida/métodos , Disruptores Endócrinos/análise , Exposição Ambiental/análise , Poluentes Ambientais/análise , Saliva/química , Espectrometria de Massas em Tandem/métodos , Disruptores Endócrinos/sangue , Poluentes Ambientais/sangue , Humanos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Espectrometria de Fluorescência
5.
Ecotoxicol Environ Saf ; 162: 625-632, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30036827

RESUMO

17-a-ethinylestradiol (EE2) belongs to the increasing list of Endocrine Disruptors Chemicals (EDCs), able to interfere with the endocrine system in both vertebrates and invertebrates. Regardless of its great dispersion in the environment, to date there is still little knowledge about its action mechanisms and harmful effects in invertebrates. To better evaluate its potential role in invertebrates, we used the model system Drosophila melanogaster, an insect in which the hormonal response has been widely described. The effects of EE2 in D.melanogaster adults have been evaluated by using life traits as well as molecular endpoints. It was found that EE2 significantly decreases survival and fertility in both sexes, with a higher effect in female flies, as well as affects the expression of the Ecdysone Receptor (EcR), Estrogen Related Receptor (ERR), Yolk protein2 (Yp2) and yolkless (yl) genes. In conclusion, our results suggest that EE2 treatment may have potential toxic and endocrine effects on Drosophila melanogaster adults of both sexes. In particular, our data provide an indication that, after EE2 treatment, two of the genes involved in the vitellogenesis process (yl and Yp2) are transcribed in adult males where are mostly silent, and suggest future studies forward their use as potential molecular markers to EDCs exposure in Drosophila male.


Assuntos
Drosophila melanogaster/efeitos dos fármacos , Etinilestradiol/toxicidade , Fatores Sexuais , Animais , Relação Dose-Resposta a Droga , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Proteínas do Ovo/genética , Disruptores Endócrinos/toxicidade , Feminino , Fertilidade/efeitos dos fármacos , Proteínas de Insetos/genética , Masculino , Receptores de Superfície Celular/genética , Receptores de Estrogênio/genética , Receptores de Esteroides/genética , Vitelogênese/efeitos dos fármacos , Vitelogeninas/genética
6.
Int J Pharm ; 520(1-2): 21-28, 2017 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-28130197

RESUMO

In this work, curcumin (CURC)-encapsulating nanoparticles (NPs), made up of an amphiphilic blend of poloxamers and PLGA (PPC NPs) at different polymer concentrations, were prepared by nanoprecipitation. CURC was preliminarily complexed with (2-hydroxypropyl)-ß-cyclodextrin (HPßCD) to improve its loading efficiency. The formation of host-guest complexes of CURC with HPßCD (CD-CURC) was confirmed by means of 1HNMR studies and differential scanning calorimetry (DSC). Nanoprecipitation allowed to obtain NPs with a small size (90-120nm depending on the polymer concentration), a narrow size distribution and stable in water for 30days at 4°C and in RPMI-1640 cell culture medium up to 72h at 37°C. The in vitro release of CD-CURC, sustained up to 5days, was governed mainly by a diffusive mechanism. It was also found that the produced NPs were efficiently internalized by mesothelioma cells (MSTO-211H) in the cytoplasmic space, at an extent strongly dependent on NP size and polydispesity index, therefore pointing at the importance of NP preparation method in improving their uptake.


Assuntos
Curcumina/química , Curcumina/farmacologia , Portadores de Fármacos/química , Nanopartículas/química , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Precipitação Química , Curcumina/administração & dosagem , Curcumina/farmacocinética , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Humanos , Ácido Láctico/química , Nanopartículas/metabolismo , Tamanho da Partícula , Poloxâmero/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
7.
Environ Sci Pollut Res Int ; 24(2): 1270-1282, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27771877

RESUMO

The removal of methylparaben (MP), a well-known endocrine disruptor, from aqueous solutions using polyacrylonitrile (PAN) beads has been studied under batch conditions, at room temperature and at different initial MP concentrations. The kinetic and equilibrium results have been analyzed. Kinetic modeling analysis has been carried out with three different types of adsorption models: pseudo-first-order, pseudo-second-order, and Elovich model. Kinetic data analysis indicated that the adsorption was a second-order process. The MP adsorption by PAN was also quantitatively evaluated by using the equilibrium adsorption isotherm models of Langmuir, Freundlich, Dubinin-Radushkevich (D-R), and Temkin and the applicability of the respective isotherm equations has been compared through the correlation coefficients. Adsorption data resulted well fitted by the Freundlich isotherm model. Data of MP adsorption have also been used to test different adsorption diffusion models. The diffusion rate equations inside particulate of Dumwald-Wagner and the intraparticle diffusion model have been used to calculate the diffusion rate. The actual rate-controlling step involved in the MB adsorption process was determined. The kinetic expression by Boyd gave the right indications. All together, our results indicate that PAN beads are a useful tool to remediate water bodies polluted by endocrine disruptors.


Assuntos
Resinas Acrílicas/química , Parabenos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Difusão , Concentração de Íons de Hidrogênio , Cinética , Soluções , Termodinâmica
8.
Pediatr Obes ; 12(5): 380-387, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-27187765

RESUMO

BACKGROUND: Bisphenol A (BPA) exposure has been associated with increased incidence of diabetes and obesity in adults. OBJECTIVES: To evaluate whether an association between BPA urinary levels and insulin resistance as well as adiponectin and resistin production and serum concentrations may occur in obese children. METHODS: Clinical and biochemical features of 141 obese children were collected. Serum resistin and adiponectin were evaluated. Insulin resistance and urinary BPA levels were assessed. Moreover, the effect of BPA on adiponectin and resistin gene expression in adipocytes from eight normal weight prepubertal children was investigated by quantitative real-time RT-PCR (qPCR). RESULTS: Direct association between BPA and homeostasis model assessment (r = 0.23; p: 0.0069) and a strong inverse association between BPA and adiponectin have been found (r = -0.48; p < 0.0001). In adipocytes, resistin expression was detected only after BPA treatment, while adiponectin expression resulted down-regulated after BPA exposure (p < 0.05 at both 10 and 100 nM BPA concentrations). CONCLUSIONS: We suggest the involvement of BPA in the development of insulin resistance in childhood obesity highlighting that urinary BPA levels are directly associated with insulin resistance regardless of BMI. This association may be explained, at least partly, by the findings that BPA affects resistin and adiponectin production in adipose tissue cultures.


Assuntos
Adiponectina/metabolismo , Compostos Benzidrílicos/efeitos adversos , Resistência à Insulina/genética , Obesidade Infantil/genética , Fenóis/efeitos adversos , Resistina/metabolismo , Tecido Adiposo/metabolismo , Adolescente , Compostos Benzidrílicos/urina , Criança , Estudos Transversais , Feminino , Expressão Gênica , Humanos , Masculino , Fenóis/urina , Reação em Cadeia da Polimerase em Tempo Real
9.
Mar Pollut Bull ; 105(1): 37-42, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26971230

RESUMO

During two seasonal trawl surveys (April and October, 2012), red mullet specimens were caught from two sites of the northern Sicilian coast (Western Mediterranean), characterized by different degrees of pollution, to assess whether their digestive enzymes could be cost-effective diagnostic tools for endocrine disruption. Pepsin, chymotrypsin, carboxypeptidases A and B, amylase and lipase were measured in the digestive tract of each fish. During both samplings, significant differences in the digestive enzymatic patterns of fish collected from the two sites were found. In April, pepsin and lipase contents were significantly lower in fish from the most impacted site than in those from the reference site. In October, the enzymatic patterns showed trends different from spring, with controversial results for carboxypeptidases A and B and amylase. Pepsin and lipase patterns suggest a detrimental effect played by organic pollutants and the use of these enzymes as possible biomarkers of exposure to endocrine disruptors.


Assuntos
Sistema Digestório/enzimologia , Disruptores Endócrinos/toxicidade , Monitoramento Ambiental/métodos , Smegmamorpha/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Disruptores Endócrinos/metabolismo , Poluição Ambiental , Peixes , Perciformes , Alimentos Marinhos , Estações do Ano , Poluentes Químicos da Água/metabolismo
10.
Mol Cell Endocrinol ; 422: 74-83, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26604029

RESUMO

In recent years, impaired fertility and endometrium related diseases are increased. Many evidences suggest that environmental pollution might be considered a risk factor for endometrial physiopathology. Among environmental pollutants, endocrine disrupting chemicals (EDCs) act on endocrine system, causing hormonal imbalance which, in turn, leads to female and male reproductive dysfunctions. In this work, we studied the effects of triclosan (TCL) and bisphenol A (BPA), two widespread EDCs, on human endometrial stromal cells (ESCs), derived from endometrial biopsies from woman not affected by endometriosis. Cell proliferation, cell cycle, migration and decidualization mechanisms were investigated. Treatments have been performed with both the EDCs separately or in presence and in absence of progesterone used as decidualization stimulus. Both TCL and BPA did not affect cell proliferation, but they arrested ESCs at G2/M phase of cell cycle enhancing cell migration. TCL and BPA also increased gene expression and protein levels of some decidualization markers, such as insulin growth factor binding protein 1 (IGFBP1) and prolactin (PRL), amplifying the effect of progesterone alone. All together, our data strongly suggest that TCL and BPA might alter human endometrium physiology so affecting fertility and pregnancy outcome.


Assuntos
Decídua/citologia , Disruptores Endócrinos/efeitos adversos , Endométrio/citologia , Células Estromais/efeitos dos fármacos , Triclosan/efeitos adversos , Adulto , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Decídua/metabolismo , Endométrio/efeitos dos fármacos , Endométrio/metabolismo , Feminino , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Pessoa de Meia-Idade , Progesterona/farmacologia , Prolactina/genética , Prolactina/metabolismo , Células Estromais/citologia , Células Estromais/metabolismo , Regulação para Cima
11.
J Mol Endocrinol ; 54(3): 289-303, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25878060

RESUMO

Bisphenol A (BPA) is a xenobiotic endocrine-disrupting chemical. In vitro and in vivo studies have indicated that BPA alters endocrine-metabolic pathways in adipose tissue, which increases the risk of metabolic disorders and obesity. BPA can affect adipose tissue and increase fat cell numbers or sizes by regulating the expression of the genes that are directly involved in metabolic homeostasis and obesity. Several studies performed in animal models have accounted for an obesogen role of BPA, but its effects on human adipocytes - especially in children - have been poorly investigated. The aim of this study is to understand the molecular mechanisms by which environmentally relevant doses of BPA can interfere with the canonical endocrine function that regulates metabolism in mature human adipocytes from prepubertal, non-obese children. BPA can act as an estrogen agonist or antagonist depending on the physiological context. To identify the molecular signatures associated with metabolism, transcriptional modifications of mature adipocytes from prepubertal children exposed to estrogen were evaluated by means of microarray analysis. The analysis of deregulated genes associated with metabolic disorders allowed us to identify a small group of genes that are expressed in an opposite manner from that of adipocytes treated with BPA. In particular, we found that BPA increases the expression of pro-inflammatory cytokines and the expression of FABP4 and CD36, two genes involved in lipid metabolism. In addition, BPA decreases the expression of PCSK1, a gene involved in insulin production. These results indicate that exposure to BPA may be an important risk factor for developing metabolic disorders that are involved in childhood metabolism dysregulation.


Assuntos
Adipócitos/metabolismo , Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Fenóis/toxicidade , Transcriptoma/efeitos dos fármacos , Adipócitos/efeitos dos fármacos , Células Cultivadas , Criança , Estradiol/farmacologia , Feminino , Humanos , Insulina/biossíntese , Insulina/metabolismo , Secreção de Insulina , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Doenças Metabólicas/metabolismo , Doenças Metabólicas/patologia
12.
Eur J Pharm Biopharm ; 93: 37-45, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25794477

RESUMO

The pharmacological potential of curcumin (CURC) is severely restricted because of its low water solubility/absorption, short half-life and poor bioavailability. To overcome these issues, CURC-loaded nanoparticles (NPs) were produced by a double emulsion technique. In particular, NPs were made up of an amphiphilic blend of poloxamers and PLGA to confer stealth properties to the NPs to take advantage of the enhanced permeability and retention (EPR) effect. Different surface properties of NPs made up of bare PLGA and PLGA/poloxamer blend were confirmed by the different interactions of these NPs with serum proteins and also by their ability to be internalized by mesothelioma cell line. The uptake of PLGA/poloxamer NPs induces a persistent block in G0/G1 phase of the cell cycle up to 72 h, thus overcoming the drug tolerance phenomenon, normally evidenced with free CURC.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Curcumina/farmacologia , Portadores de Fármacos , Ácido Láctico/química , Mesotelioma/tratamento farmacológico , Nanopartículas , Poloxâmero/química , Ácido Poliglicólico/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Química Farmacêutica , Curcumina/química , Curcumina/metabolismo , Estabilidade de Medicamentos , Tolerância a Medicamentos , Humanos , Cinética , Mesotelioma/patologia , Nanomedicina , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ligação Proteica , Solubilidade , Propriedades de Superfície , Tecnologia Farmacêutica/métodos
13.
J Hazard Mater ; 291: 129-35, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-25781217

RESUMO

Serratia rubidiae, Pseudomonas aeruginosa and Escherichia coli K12 have been studied for their ability of Bisphenol A removal from aqueous systems and biofilm formation on activated granule carbon. Mathematical equations for biodegradation process have been elaborated and discussed. P. aeruginosa was found the best strain to be employed in the process of Bisphenol A removal. The yield in BPA removal of a P. aeruginosa biofilm grown on GAC and operating in a fluidized bed reactor has been evaluated. The results confirm the usefulness in using biological activated carbon (BAC process) to remove phenol compounds from aqueous systems.


Assuntos
Compostos Benzidrílicos/isolamento & purificação , Reatores Biológicos/microbiologia , Fenóis/isolamento & purificação , Pseudomonas aeruginosa/metabolismo , Adsorção , Biodegradação Ambiental , Biofilmes , Carbono , Carvão Vegetal/química , Poluentes da Água/isolamento & purificação
14.
Pharm Res ; 32(2): 362-74, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25092068

RESUMO

PURPOSE: Combined treatment based on cisplatin-loaded Poly(D,L-lactic-co-glicolic)acid (PLGA) nanoparticles (NP-C) plus the NSAID piroxicam was used as novel treatment for mesothelioma to reduce side effects related to cisplatin toxicity. METHODS: PLGA nanoparticles were prepared by double emulsion solvent evaporation method. Particle size, drug release profile and in vitro cellular uptake were characterized by TEM, DLS, LC/MS and fluorescence microscopy. MSTO-211H cell line was used to analyse NP-C biological efficacy by FACS and protein analysis. RESULTS: Cisplatin was encapsulated in 197 nm PLGA nanoparticles with 8.2% drug loading efficiency and 47% encapsulation efficiency. Cisplatin delivery from nanoparticles reaches 80% of total encapsulated drug in 14 days following a triphasic trend. PLGA nanoparticles in MSTO-211H cells were localized in the perinuclear space NP-C in combination with piroxicam induced apoptosis using a final cisplatin concentration 1.75 fold less than free drug. Delivered cisplatin cooperated with piroxicam in modulating cell cycle regulators as caspase-3, p53 and p21. CONCLUSIONS: Cisplatin loaded PLGA nanoparticles plus piroxicam showed a good efficacy in exerting cytotoxic activity and inducing the same molecular apoptotic effects of the free drugs. Sustained cisplatin release allowed to use less amount of drug, decreasing toxic side effects. This novel approach could represent a new strategy for mesothelioma treatment.


Assuntos
Apoptose/efeitos dos fármacos , Cisplatino/administração & dosagem , Ácido Láctico/administração & dosagem , Mesotelioma , Nanopartículas/administração & dosagem , Piroxicam/administração & dosagem , Ácido Poliglicólico/administração & dosagem , Apoptose/fisiologia , Linhagem Celular Tumoral , Cisplatino/metabolismo , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/metabolismo , Combinação de Medicamentos , Humanos , Mesotelioma/metabolismo , Nanopartículas/metabolismo , Piroxicam/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Resultado do Tratamento
15.
Sensors (Basel) ; 11(4): 3483-97, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22163807

RESUMO

A monolithic silica gel matrix with entrapped glucose oxidase (GOD) was constructed as a bioactive element in an optical biosensor for glucose determination. Intrinsic fluorescence of free and immobilised GOD was investigated in the visible range in presence of different glucose concentrations by time-resolved spectroscopy with time-correlated single-photon counting detector. A three-exponential model was used for analysing the fluorescence transients. Fractional intensities and mean lifetime were shown to be sensitive to the enzymatic reaction and were used for obtaining calibration curve for glucose concentration determination. The sensing system proposed achieved high resolution (up to 0.17 mM) glucose determination with a detection range from 0.4 mM to 5 mM.


Assuntos
Técnicas Biossensoriais/métodos , Enzimas Imobilizadas/química , Glucose Oxidase/química , Glucose/análise , Flavina-Adenina Dinucleotídeo/química , Fluorescência , Transição de Fase
16.
Ann N Y Acad Sci ; 1163: 457-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19456386

RESUMO

The effect of tamoxifen (TAM) on the black goby Gobius niger exposed to different contaminants was analyzed by investigating the response of a set of biomarkers involved in reproduction and cell recovery. While the effects of TAM are well known in mammalian breast and endometrial cells (with severe consequences on physiology), few contrasting data are available for fish. In this work the expression of vitellogenin (vtg), estrogen receptor alpha (ERalpha), cytochrome P4501A1 (CYP1A1), and heat shock protein 70 (HSP70) genes was evaluated in fish treated with TAM alone or co-injected with nonylphenol, estradiol, and beta-naphtoflavone. The induction of vtg observed in male fish treated with estrogens was significantly lowered by the co-injection of TAM. ERalpha and HSP70 gene expressions were significantly upregulated in all experimental groups; however, TAM treatment did not change CYP1A1 gene expression. Together these data confirm the mixed estrogenic/anti-estrogenic action of TAM, indicating its interference in fish reproduction and physiology.


Assuntos
Disruptores Endócrinos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Perciformes/fisiologia , Reprodução/efeitos dos fármacos , Tamoxifeno/farmacologia , Animais , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Receptor alfa de Estrogênio/genética , Proteínas de Choque Térmico HSP70/genética , Masculino , Vitelogeninas/genética
17.
IUBMB Life ; 60(12): 843-52, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18767177

RESUMO

A wide variety of environmental contaminants exert estrogenic actions in wildlife, laboratory animals, and in human beings through binding to nuclear estrogen receptors (ERs). Here, the mechanism(s) of bisphenol A (BPA) to induce cell proliferation and the occurrence of its bioremediation by treatment with laccase are reported. BPA, highly present in natural world and considered as a model of environmental estrogen action complexity, promotes human cancer cell proliferation via ERalpha-dependent signal transduction pathways. Similar to 17beta-estradiol, BPA increases the phosphorylation of both extracellular regulated kinase and AKT. Specific inhibitors of these kinase completely block the BPA effect on cancer cell proliferation. Notably, high BPA concentrations (i.e., 0.1 and 1 mM) are cytotoxic even in ERalpha-devoid cancer cells, indicating that an ERalpha-independent mechanism participates to BPA-induced cytotoxicity. On the other hand, BPA oxidation by laccase impairs the binding of this environmental estrogen to ERalpha loosing at all ERalpha-dependent effect on cancer cell proliferation. Moreover, the laccase-catalyzed oxidation of BPA reduces the BPA cytotoxic effect. Thus, laccase appears to impair BPA action(s), representing an invaluable bioremediation enzyme.


Assuntos
Proliferação de Células/efeitos dos fármacos , Receptor alfa de Estrogênio/metabolismo , Estrogênios não Esteroides/farmacologia , Lacase/metabolismo , Fenóis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Compostos Benzidrílicos , Células HeLa/efeitos dos fármacos , Humanos , Immunoblotting , Espectrometria de Massas , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Neoplasias/patologia , Fosforilação/efeitos dos fármacos , Plasmídeos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transfecção
18.
Int J Biol Macromol ; 43(4): 339-45, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18675298

RESUMO

Acetylcholinesterase (AChE) was immobilized on two different composite membranes constituted by a chemically modified poly-acrylonitrile (PAN) membrane plus a layer of tethered chitosan of different molecular weight, 10 kDa or 400 kDa. AChE was also directly immobilized on a chemically modified PAN membrane with NaOH and ethylenediamine (EDA) without chitosan. To know how the different supports affected the enzyme activity and the kinetic parameters, the AChE activity was studied in the soluble form and in the insoluble form with all the three types of modified PAN membranes. The best performance was obtained by the modified PAN membrane having the chitosan with the lower molecular weight. The results concerning the AChE inhibition by methyl-paraoxon and the subsequent reactivation by pyridine-2-aldoxime methochloride (2-PAM) are presented and discussed. The composite membrane having chitosan with the lower molecular weight appeared to be potentially useful for applications in the field of biosensors.


Assuntos
Acetilcolinesterase/metabolismo , Resinas Acrílicas/metabolismo , Enzimas Imobilizadas/antagonistas & inibidores , Enzimas Imobilizadas/metabolismo , Aminas/metabolismo , Animais , Inibidores da Colinesterase/farmacologia , Electrophorus , Ativação Enzimática/efeitos dos fármacos , Cinética , Membranas Artificiais , Paraoxon/farmacologia , Especificidade por Substrato/efeitos dos fármacos
19.
Sensors (Basel) ; 7(10): 2049-2061, 2007 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-28903213

RESUMO

Liquid samples of clarified apple and apricot juices at different productionstages were investigated using visible light micro-Raman spectroscopy in order to assessits potential in monitoring fruit juice production. As is well-known, pectin plays a strategicrole in the production of clarified juice and the possibility of using Raman for its detectionduring production was therefore evaluated. The data analysis has enabled the clearidentification of pectin. In particular, Raman spectra of apple juice samples from washedand crushed fruits revealed a peak at 845 cm-1 (typical of pectin) which disappears in theRaman spectra of depectinised samples. The fructose content was also revealed by thepresence of four peaks at 823 cm-1, 872 cm-1, 918 cm-1 and 975 cm-1. In the case of apricotjuice, several Raman fingerprints of ß-carotene at 1008, 1159 and 1520 cm-1 were alsohighlighted. Present results resulted interesting for the exclusive use of optical methods forthe quantitative determination of the above-mentioned substances in place of thebiochemical assays generally used for this purpose, which are time consuming and requiredifferent chemical reagents for each of them.

20.
Sensors (Basel) ; 7(11): 2612-2625, 2007 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-28903249

RESUMO

Changes in steady-state UV fluorescence emission from free or immobilizedglucose oxidase have been investigated as a function of glucose concentration.Immobilized GOD has been obtained by entrapment into a gelatine membrane. Changes insteady-state UV fluorescence have been quantitatively characterized by means ofoptokinetic parameters and their values have been compared with those previouslyobtained for FAD fluorescence in the visible range. The results confirmed that greatercalibration ranges are obtained from UV signals both for free and immobilized GOD inrespect to those obtained under visible fluorescence excitation. An alternative method tothe use UV fluorescence for glucose determination has been investigated by using timecourse measurements for monitoring the differential fluorescence of the redox forms of theFAD in GOD. Also in this case quantitative analysis have been carried out and acomparison with different experimental configurations has been performed. Time coarsemeasurements could be particularly useful for glucose monitoring in complex biologicalfluids in which the intrinsic UV fluorescence of GOD could be not specific by consideringthe presence of numerous proteins.

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