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1.
Materials (Basel) ; 16(17)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37687569

RESUMO

Cadmium-based alloyed quantum dots are one of the most popular metal chalcogenides in both the industrial and research fields owing to their extraordinary optical and electronic properties that can be manipulated by varying the compositional ratio in addition to size control. This report aims to cover the main information concerning the synthesis techniques, properties, and applications of Cd-based alloyed quantum dots. It provides a comprehensive overview of the most common synthesis methods for these QDs, which include hot injection, co-precipitation, successive ionic layer adsorption and reaction, hydrothermal, and microwave-assisted synthesis methods. This detailed literature highlights the optical and structural properties of both ternary and quaternary quantum dots. Also, this review provides the high-potential applications of various alloyed quantum dots.

2.
Polymers (Basel) ; 15(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36904398

RESUMO

To limit the dangers posed by Cu(II) pollution, chitosan-nanohybrid derivatives were developed for selective and rapid copper adsorption. A magnetic chitosan nanohybrid (r-MCS) was obtained via the co-precipitation nucleation of ferroferric oxide (Fe3O4) co-stabilized within chitosan, followed by further multifunctionalization with amine (diethylenetriamine) and amino acid moieties (alanine, cysteine, and serine types) to give the TA-type, A-type, C-type, and S-type, respectively. The physiochemical characteristics of the as-prepared adsorbents were thoroughly elucidated. The superparamagnetic Fe3O4 nanoparticles were mono-dispersed spherical shapes with typical sizes (~8.5-14.7 nm). The adsorption properties toward Cu(II) were compared, and the interaction behaviors were explained with XPS and FTIR analysis. The saturation adsorption capacities (in mmol.Cu.g-1) have the following order: TA-type (3.29) > C-type (1.92) > S-type (1.75) > A-type(1.70) > r-MCS (0.99) at optimal pH0 5.0. The adsorption was endothermic with fast kinetics (except TA-type was exothermic). Langmuir and pseudo-second-order equations fit well with the experimental data. The nanohybrids exhibit selective adsorption for Cu(II) from multicomponent solutions. These adsorbents show high durability over multiple cycles with desorption efficiency > 93% over six cycles using acidified thiourea. Ultimately, QSAR tools (quantitative structure-activity relationships) were employed to examine the relationship between essential metal properties and adsorbent sensitivities. Moreover, the adsorption process was described quantitatively, using a novel three-dimensional (3D) nonlinear mathematical model.

3.
Polymers (Basel) ; 15(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36904508

RESUMO

In this work, silver (Ag) anchored over graphene (GN) wrapped polypyrrole (PPy)@ nickel hydroxide (Ni(OH)2) nanocomposites were synthesized through a combination of oxidative polymerization and hydrothermal processes. The synthesized Ag/GN@PPy-Ni(OH)2 nanocomposites were characterized for their morphological characteristics by field emission scanning electron microscopy (FESEM), while the structural investigations were done by X-ray diffraction and X-ray photoelectron spectroscopy (XPS). The FESEM studies showed Ni(OH)2 flakes and silver particles attached over the surface of PPy globules, along with the presence of GN sheets and spherical silver particles. The structural analysis also showed the presence of constituents, i.e., Ag, Ni(OH)2, PPy, GN, and their interaction, therefore vouching that the synthesis protocol is efficacious. The electrochemical (EC) investigations were done in potassium hydroxide (1 M KOH) using a three electrode setup. The quaternary Ag/GN@PPy-Ni(OH)2 nanocomposite electrode showed the highest specific capacity of 237.25 C g-1. The highest electrochemical performance of the quaternary nanocomposite is associated with the synergistic/additional effect of PPy, Ni(OH)2, GN, and Ag. The assembled supercapattery with Ag/GN@PPy-Ni(OH)2 as a positive and activated carbon (AC) as a negative electrode displayed eminent energy density of 43.26 Wh kg-1 with the associated power density of 750.00 W kg-1 at a current density of 1.0 A g-1. The cyclic stability of the supercapattery (Ag/GN@PPy-Ni(OH)2//AC), comprising a battery-type electrode, displayed a high cyclic stability of 108.37% after 5500 cycles.

4.
Front Vet Sci ; 9: 1042956, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36544552

RESUMO

Fish is one of the most valuable foods with high-quality animal protein. However, aquaculture, or ingesting contaminated food, allows organochlorine pesticides (OCPs) to enter the fish's body, and therefore, it negatively impacted public health. One-hundred and twenty random samples of Clupea harengus (C. harengus), Mugil cephalus (M. cephalus), Sardinella aurita (S. aurita), Oreochromis niloticus (O. niloticus), Neptunus pelagicus (N. pelagicus) and Sepia savigngi (S. savigngi) (n = 20 each) were collected from local markets in Mansoura city, Egypt. Samples were checked to see whether any residues of OCPs with the application of risk assessment due to their consumption by Mansoura citizens. The findings indicated that summation hexachlorocyclohexane (∑HCH) in examined seafood samples ranged from 0.27 ± 0.13 in N. pelagicus to 61.61 ± 52.03 µg.kg-1 in S. aurita. Also, the γ-HCH isomer was considered the more prominent among isomers. Hexachlorobenzene (HCB) was found in five different species, with mean values of 2.03 ± 1.85, 1.5.7 ± 1.17, 0.94 ± 0.87, 0.35 ± 0.06, and 0.18 ± 0.06 µg.kg-1 in C. harengus, S. aurita, M. cephlaus, O. niloticus, and S. savigngi. Moreover, summation of Heptachlors (∑HPTs) was 10.19 ± 7.63, 1.27 ± 0.26, 2.58 ± 0.11, 0.95 ± 0.12, 0.21 ± 0.11 and 0.32 ± 0.03 µg.kg-1 of wet weight in examined C. harengus, M. cephlaus, S. aurita, O. niloticus, N. pelagicus, and S. savigngi. Aldrin and dieldrin residues were 3.75 ± 1.31 and 4.86 ± 1.33 µg.kg-1 in C. harengu, meanwhile they were 1.61 ± 0.77 and 0.78 ± 0.04 µg.kg-1in M. cephalus. Dichlorodiphenyldichloroethylene (pp-DDE) was dominant in all examined species within different concentrations 5.08 ± 4.12, 0.98 ± 0.10, 3.07 ± 0.91, 0.93 ± 0.27, 0.08 ± 0.01 and 0.35 ± 0.02 µg.kg-1 in C. harengus, M. cephlaus, S. aurita, O. niloticus, N. pelagicus and S. savigngi, respectively. We concluded that all examined seafood samples were lower than the recommended maximum residue limit. Also, the estimated daily intake was less than the permitted daily intake. Non-carcinogenic indices of target hazard quotient and hazard index for OCPs in all examined species were less than 1.

5.
Polymers (Basel) ; 14(21)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36365772

RESUMO

The major components of supercapacitor are electrodes and electrolytes which are fabricated using various materials and methods. Hydrogel is one such material that is used in supercapacitors as electrodes and electrolytes or both. Hydrogels are usually described as a soft and porous network of polymer materials that can swell in water because of the hydrophilic nature of its polymer chains, compriseng a 3D structure. It is well known that supercapacitors possess high-power density but low energy density. For enhancing energy density of these electrochemical cells and a boost in its electrochemical performance and specific capacity, binder free conducting polymer hydrogel electrodes have gained immense attention, especially polyaniline (PANI) and polypyrrole (PPy). Therefore, in this work, chemically crosslinked PVA/Agar hydrogel electrolytes have been prepared and employed. Agar has been added in PVA since it is environmentally friendly, biodegradable, and cost-effective natural polymer. Subsequently, the binder free polyaniline/polypyrrole electrodes were grown on the PVA/Agar hydrogel electrolytes to fabricate all-in-one flexible hydrogels. The synthesized hydrogels were characterized using X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) analysis, Field emission scanning electron microscope (FESEM) and mechanical studies. Then, the all-in-one flexible supercapacitors were fabricated using the hydrogels. The electrochemical studies such cyclic voltammetry (CV), galvanic charge discharge (GCD), and electrochemical impedance spectroscopy (EIS) studies. The fabricated all-in-one lamination free supercapacitors showed promising results and by comparing all four samples, PAP2 where 5 mL of PVA was used in combination with 3 mL of Agar and 5 mL of PANI and PPy each, exhibited the highest areal capacitance of 750.13 mF/cm2, energy density of 103.02 µWh/cm2, and 497.22 µW/cm2 power density. The cyclic stability study revealed the 149% capacity retention after 15,000 cycles.

6.
J Control Release ; 352: 338-370, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36206948

RESUMO

Glioma is often referred to as one of the most dreadful central nervous system (CNS)-specific tumors with rapidly-proliferating cancerous glial cells, accounting for nearly half of the brain tumors at an annual incidence rate of 30-80 per a million population. Although glioma treatment remains a significant challenge for researchers and clinicians, the rapid development of nanomedicine provides tremendous opportunities for long-term glioma therapy. However, several obstacles impede the development of novel therapeutics, such as the very tight blood-brain barrier (BBB), undesirable hypoxia, and complex tumor microenvironment (TME). Several efforts have been dedicated to exploring various nanoformulations for improving BBB permeation and precise tumor ablation to address these challenges. Initially, this article briefly introduces glioma classification and various pathogenic factors. Further, currently available therapeutic approaches are illustrated in detail, including traditional chemotherapy, radiotherapy, and surgical practices. Then, different innovative treatment strategies, such as tumor-treating fields, gene therapy, immunotherapy, and phototherapy, are emphasized. In conclusion, we summarize the article with interesting perspectives, providing suggestions for future glioma diagnosis and therapy improvement.


Assuntos
Neoplasias Encefálicas , Glioma , Nanoestruturas , Humanos , Glioma/terapia , Glioma/tratamento farmacológico , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/tratamento farmacológico , Nanomedicina , Nanoestruturas/uso terapêutico , Barreira Hematoencefálica , Microambiente Tumoral
7.
Polymers (Basel) ; 14(13)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35808614

RESUMO

Nuclear power facilities are being expanded to satisfy expanding worldwide energy demand. Thus, uranium recovery from secondary resources has become a hot topic in terms of environmental protection and nuclear fuel conservation. Herein, a mesoporous biosorbent of a hybrid magnetic-chitosan nanocomposite functionalized with cysteine (Cys) was synthesized via subsequent heterogeneous nucleation for selectively enhanced uranyl ion (UO22+) sorption. Various analytical tools were used to confirm the mesoporous nanocomposite structural characteristics and confirm the synthetic route. The characteristics of the synthesized nanocomposite were as follows: superparamagnetic with saturation magnetization (MS: 25.81 emu/g), a specific surface area (SBET: 42.56 m2/g) with a unipore mesoporous structure, an amine content of ~2.43 mmol N/g, and a density of ~17.19/nm2. The experimental results showed that the sorption was highly efficient: for the isotherm fitted by the Langmuir equation, the maximum capacity was about 0.575 mmol U/g at pH range 3.5-5.0, and Temperature (25 ± 1 °C); further, there was excellent selectivity for UO22+, likely due to the chemical valent difference. The sorption process was fast (~50 min), simulated with the pseudo-second-order equation, and the sorption half-time (t1/2) was 3.86 min. The sophisticated spectroscopic studies (FTIR and XPS) revealed that the sorption mechanism was linked to complexation and ion exchange by interaction with S/N/O multiple functional groups. The sorption was exothermic, spontaneous, and governed by entropy change. Desorption and regeneration were carried out using an acidified urea solution (0.25 M) that was recycled for a minimum of six cycles, resulting in a sorption and desorption efficiency of over 91%. The as-synthesized nanocomposite's high stability, durability, and chemical resistivity were confirmed over multiple cycles using FTIR and leachability. Finally, the sorbent was efficiently tested for selective uranium sorption from multicomponent acidic simulated nuclear solution. Owing to such excellent performance, the Cys nanocomposite is greatly promising in the uranium recovery field.

8.
J Colloid Interface Sci ; 588: 637-645, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33267956

RESUMO

Supercapacitors are deemed as reliable power sources for portable devices and electric vehicles. Electrode materials with high energy and power densities are greatly needed. Herein, we designed reduced-graphene-oxide supported nickel-cobalt layered double hydroxide nanosheets (NiCo-LDH/rGO) as electrode materials. The introduction of graphene could largely enhance the conductivity, and the supported NiCo-LDH could effectively prevent graphene from self-aggregation. Thanks to the synergistic effect of conductive graphene and electro-active LDH, the nanocomposites delivered a capacitance of 1675 F g-1 at 1 A g-1 and decent rate performance (capacitance retention of 83.8% at 10 A g-1); while NiCo-LDH could only exhibited a capacitance of 920 F g-1 at 1 A g-1 and 81.5% of the capacitance remained at 10 A g-1. The asymmetric supercapacitors assembled with NiCo-LDH/rGO and activated carbon (AC) delivered high energy density and power density, up to 49.9 Wh kg-1 and 3747.9 W kg-1, respectively. The appealing electrochemical performance indicates its huge application potential in supercapacitors.

9.
J Agric Food Chem ; 67(27): 7716-7725, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31131603

RESUMO

Plasmalogens derived from dietary phospholipids are considered to be potential protectors against oxidation-related disorders, while lead (Pb) is an environmental contaminant worldwide and is known to induce oxidative stress. However, the protective and antilipid oxidative effects of individual plasmalogen species against Pb damage have received little attention. In this study, six plasmalogen species (with either choline or ethanolamine as the headgroup and p16:0/18:1, p16:0/18:2, or p16:0/20:5 as the side chains) were evaluated in human hepatoma cells. Plasmalogen species showed a remarkable recovery in cell viability as well as elimination of reactive oxygen species and suppressed the accumulation of phosphatidylcholine hydroperoxides (from 63.6 ± 1.8% to 80.3 ± 2.9%) and phosphatidylethanolamine hydroperoxides (from 25.7 ± 9.3% to 76.1 ± 3.7%). Moreover, plasmalogens significantly upregulated the gene expression levels of a series of antioxidant enzymes that are regulated via the Nrf-2-dependent pathway. This study suggested that choline and ethanolamine plasmalogens could prevent Pb-induced cytotoxicity and lipid oxidation in HepG2 cells.


Assuntos
Chumbo/toxicidade , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Plasmalogênios/farmacologia , Antioxidantes/análise , Antioxidantes/farmacologia , Poluentes Ambientais/toxicidade , Expressão Gênica/efeitos dos fármacos , Glutationa Transferase/genética , Células Hep G2 , Humanos , Fígado/enzimologia , Fígado/metabolismo , NAD(P)H Desidrogenase (Quinona)/genética , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo , Regulação para Cima/efeitos dos fármacos
10.
Indian J Nephrol ; 29(1): 28-33, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30814790

RESUMO

Sickle cell disease (SCD) is a hereditary hemoglobinopathy characterized by abnormal hemoglobin production which leads to hemolytic anemia and intermittent occlusion of small blood vessels, which further leads to tissue ischemia, chronic organ damage, and organ dysfunction including urinary system. To measure the serum levels of cystatin-C and beta 2 microglobulin in pediatric patients with SCDand to investigate their significance as early biomarkers of glomerular and/or renal tubular dysfunction. This study was conducted among 70 children with SCD and 40 age and sex-matched children as a control group. All subjects underwent a full medical history, through physical examination, laboratory investigations including blood urea, serum creatinine, serum ferritin, estimated glomerular filtration rate (eGFR) using the Schwartz formula, creatinine clearance, urinary albumin/creatinine ratio, serum cystatin-C, and ß-2 microglobulin levels. Pediatric patients with SCD had significantly higher serum cystatin-C and ß-2 microglobulin levels compared to controls. In addition, serum cystatin-C and ß-2 microglobulin levels were positively correlated with blood urea, serum creatinine, serum ferritin, urinary albumin/creatinine ratio, duration of iron chelating agents and frequency of blood transfusion/year. Serum cystatin-C and ß-2 microglobulin levels were negatively correlated with hemoglobin. Our data concluded that serum cystatin-C and ß-2 microglobulin had highersensitivity and specificity (91%, 90% and 85.7%, 100%, respectively) than serum creatinine (79% and85%, respectively). Serum Cystatin-C and ß-2 microglobulin are early specific and sensitive biomarkers for evaluating glomerular and tubular dysfunction in children with SCD.

11.
Chemosphere ; 144: 1365-71, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26492422

RESUMO

Food consumption is an important route of human exposure to organochlorine pesticides (OCPs). In order to assess the potential human health risks associated with OCPs, edible cattle tissues (liver, kidney and tongue) were collected from three slaughter houses in Mansoura, Zagazig and Ismailia cities, Egypt. Levels of 22 OCPs such as hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs), aldrin, dieldrin and endrin (Drins), chlordanes (CHLs), heptachlors (HPTs) and hexachlorobenzene (HCB) residues were investigated. Among the investigated OCPs, HCHs represented the most dominant group with high proportions of γ-HCH isomer (53-91% of total HCHs). Mansoura city had the highest OCPs contamination load ranged from 0.1 to 2827 ng g(-1) lw (lipid weight). Surprisingly, tongue samples collected from Mansoura showed the highest concentration of HCHs (448 ng g(-1) lw) in comparison to liver (152 ng g(-1) lw) and kidney (266 ng g(-1) lw). Generally, contamination pattern of OCPs was in the order of HCHs > Drins > CHLs > DDTs ≅ HCB and HPTs. Estimated daily intakes (EDIs) through dietary consumption of cattle tissues were lower than the recommended acceptable daily intakes (ADIs) established by FAO/WHO. However, the hazard ratios (HRs) based on cancer risk were greater than 1.0 for HCHs based on the average and 95th centile concentrations, indicating carcinogenic effects to consumers through cattle tissues consumption.


Assuntos
Monitoramento Ambiental/métodos , Contaminação de Alimentos/análise , Hidrocarbonetos Clorados/análise , Carne/análise , Resíduos de Praguicidas/análise , Aldrina/análise , Animais , Bovinos , Clordano/análise , Dieldrin/análise , Egito , Hexaclorobenzeno/análise , Hexaclorocicloexano/análise , Humanos , Medição de Risco
12.
J Food Sci ; 81(1): T275-81, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26630500

RESUMO

Lead (Pb) is an environmental pollutant that can get entry into human body through contaminated foods, drinks, and inhaled air leading to severe biological consequences, and has been responsible for many deaths worldwide. The objectives of this study were 1st to investigate the modulatory effects of environmentally relevant concentrations of Pb on AhR gene battery, which is controlling xenobiotics metabolism. 2nd, trials to reduce Pb-induced adverse effects were done using some phytochemicals like ß-carotene or ascorbic acid. Human hepatoma (HepG2) cell lines were exposed to a wide range of Pb concentrations varying from physiological to toxic levels (0 to 10 mg/L) for 24 h. High Pb concentrations (1 to 10 mg/L) significantly reduced phase I (CYP1A1 and 1A2) and phase II (UGT1A6 and NQO1) xenobiotic metabolizing enzyme mRNA expression in a mechanistic manner through the AhR regulation pathway. Additionally, these Pb concentrations induced oxidative stress in HepG2 cells in terms of production of reactive oxygen species (ROS) and induced heme oxygenase-1 mRNA expression in a concentration-dependent phenomenon. Coexposure of HepG2 cells to physiological concentrations of some micronutrients, like ß-carotene (10 µM) or ascorbic acid (0.1 mM), along with Pb (1 mg/L) for 24 h significantly reduced the levels of ROS production and recovered AhR mRNA expression into the normal levels. Thus, consumption of foods rich in these micronutrients may help to reduce the adverse effects of lead in areas with high levels of pollution.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Chumbo/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , beta Caroteno/farmacologia , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A2/metabolismo , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/efeitos adversos , Glucuronosiltransferase/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células Hep G2 , Humanos , Inativação Metabólica/efeitos dos fármacos , NAD(P)H Desidrogenase (Quinona)/metabolismo , RNA Mensageiro/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Xenobióticos/efeitos adversos
13.
J Nanosci Nanotechnol ; 15(12): 9861-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26682425

RESUMO

This paper reports the facile synthesis and detailed characterization of mercaptoacetic acid capped cadmium sulphide (CdS) quantum dots using various cadmium precursors. The mercaptoacetic acid capped CdS quantum dots were prepared by facile and simple wet chemical method and characterized by several techniques such as energy dispersive spectroscopy (EDS), X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, UV-vis. spectroscopy, photoluminescence spectroscopy, high-resolution transmission microscopy (HRTEM) and thremogravimetric analysis. The EDS studies revealed that the prepared quantum dots possess higher atomic percentage of sulfur compared to cadmium due to the coordination of thiolate to the quantum dots surfaces. The X-ray and absorption analyses exhibited that the size of quantum dots prepared by cadmium acetate is larger than the quantum dots prepared by cadmium chloride and cadmium nitrate. The increase in size can be attributed to the low stability constant of cadmium acetate in comparison with cadmium chloride and cadmium nitrate. The FTIR and thermogravimetric analysis showed that the nature of capping molecule on the surface of quantum dots are different depending on the cadmium precursors which affect the emission from CdS quantum dots. Photoemission spectroscopy revealed that the emission of quantum dots prepared by cadmium acetate has high intensity band edge emission along with low intensity trapping state emission. However the CdS quantum dots prepared by cadmium chloride and cadmium nitrate produced only trapping state emissions.

14.
J Food Sci ; 80(7): T1627-32, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26081582

RESUMO

UNLABELLED: Heterocyclic amines get entry into human body mainly through ingestion of pan-fried meats cooked at high temperatures. Exposure of the gastrointestinal tract (GIT) to ingested xenobiotics prior to delivery to the liver may lead to metabolic activation, which may explain the high incidence of GIT carcinogenesis. Therefore, this study investigated the mutagenic activation of 2 heterocyclic amines, 2-aminoanthracene (2-AA) and 3-amino-1-methyl-5H-prydo[4,3-b]indole (Trp-P-2), in the GIT of rats. In addition, the constitutive mRNA expression profiles of xenobiotic-metabolizing enzymes (XMEs) in the GIT of rats were examined. Metabolic activation of 2-AA was detected in all GIT tissues except the duodenum and rectum, and it was detected at high levels in the ileum and cecum. Furthermore, we revealed high metabolic activation of 2-AA and Trp-P-2 in the jejunum. The mRNA expression of phase I and II enzymes in rat GIT corresponded with their mutagenic activation ability. In conclusion, our results suggest that different expression levels of XME among GIT tissues may contribute to the tissue-specific differences in metabolic activation of xenobiotics such as heterocyclic amines in rats. PRACTICAL APPLICATION: This study declares mutagenic activation of 2 heterocyclic amines namely 2-aminoanthracene (2-AA) and 3-amino-1-methyl-5H-prydo[4,3-b]indole (Trp-P-2), in the gastrointestinal tract (GIT) of rats. In addition, results obtained in this study suggest that GIT tissue-specific expression of xenobiotic metabolizing enzymes may contribute to the tissue-specific mutagenesis/carcinogenesis.


Assuntos
Aminas/toxicidade , Trato Gastrointestinal/efeitos dos fármacos , Compostos Heterocíclicos/toxicidade , Mutagênicos/toxicidade , Ativação Metabólica , Animais , Antracenos/toxicidade , Carbolinas/toxicidade , Trato Gastrointestinal/enzimologia , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Mutagênese , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Sulfotransferases/genética , Sulfotransferases/metabolismo , Xenobióticos/toxicidade
15.
Food Chem Toxicol ; 48(11): 3201-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20797421

RESUMO

Ungulates (deer, cattle and horses) are reported as animal species which show extreme-accelerated metabolism of CYP1A substrates, such as ethoxyresorufin compared to rats. This study was undertaken to investigate whether accumulation of carotenoids is a possible cause for inter-species difference in CYP1A-dependent activity in this group of animals. The relationship between inter-species differences in CYP1A-dependent activity and the accumulated carotenoids and retinoids as candidates of dietary CYP1A inducers in ungulate species was clarified. Interestingly, there were positive correlations between the accumulated carotenoids, such as ß-carotene, with both EROD activity and CYP1A protein expression. These correlations were negative with the accumulated retinoids, such as retinol. The ß-carotene was major component of carotenoids in ungulates, and known as an inducer of CYP1A. On the other hand, the retinol is reported as the inhibitor of CYP1A. Other factors which affect CYP1A1 expression, such as polycyclic aromatic hydrocarbons, were also analyzed. To cancel the effects of inter-species difference in CYP1A induction signal cascade among these animals, the rat cell line (H4-II-cells) was treated with the extracted carotenoids from the examined animals. In conclusion, carotenoids and retinoids may have direct effects on the inter-species differences in CYP1A-dependent activity and protein expression.


Assuntos
Carotenoides/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Animais , Western Blotting , Carotenoides/análise , Carotenoides/farmacologia , Bovinos/fisiologia , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Citocromo P-450 CYP1A1/análise , Citocromo P-450 CYP1A1/genética , Cervos/fisiologia , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/enzimologia , Cavalos/fisiologia , Fígado/química , Fígado/metabolismo , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Ratos , Ratos Wistar/fisiologia , Especificidade da Espécie
16.
Toxicol Sci ; 116(1): 79-91, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20308224

RESUMO

Xenobiotic metabolism in oral tissues, especially in the tongue, has never been reported. In the present study, the metabolic activation/detoxification ability of promutagens in the tongue and the expression levels of related enzymes were investigated. Quantitative PCR analysis of rat tongue demonstrated constitutive messenger RNA (mRNA) expression of numerous drug-metabolizing enzymes. In particular, we detected mRNA, protein expression, and enzymatic activity of cytochrome P450 (CYP)1A1 in the tongue tissue. Metabolic activation of promutagens in the tongue was estimated using benzo[a]pyrene or heterocyclic amines (HCAs), found in cooked meat and tobacco products. Metabolic activation levels of HCAs in the tongue were comparable to those in the liver. In contrast, the expression levels of glutathione-S-transferase (GST) and uridine diphosphate-glucuronosyltransferase (UGT) in the tongue were considerably lower compared with those in the liver, and as a result, the mutagenic activity in the tongue was not decreased by GST- or UGT-dependent conjugation. Treatment of rats with sudan III, a typical inducer of CYP1A1, resulted in markedly increased CYP1A1 mRNA, protein expressions, and CYP1A-dependent enzymatic and mutagenic activities. In addition, CYP1A1 mRNA expression in carcinoma cells (SAS) was induced by sudan III exposure. In conclusion, mutagenic activation of xenobiotics and an increased risk of cancer in the tongue were observed in this study. Furthermore, ingestion of drug-metabolizing enzyme inducers has the potential to increase the metabolic activation in the tongue tissue and increase the risk of biomolecular attack by promutagens.


Assuntos
Aminas/farmacocinética , Citocromo P-450 CYP1A1/metabolismo , Compostos Heterocíclicos/farmacocinética , Língua/metabolismo , Animais , Compostos Azo/farmacocinética , Benzo(a)pireno/farmacocinética , Biotransformação , Western Blotting , Hidroxitolueno Butilado/farmacocinética , Humanos , Imuno-Histoquímica , NAD(P)H Desidrogenase (Quinona)/genética , Fator 2 Relacionado a NF-E2/genética , Reação em Cadeia da Polimerase , Ratos , Língua/enzimologia
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