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1.
Iran J Biotechnol ; 17(1): e1543, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31457037

RESUMO

BACKGROUND: Magnesium oxide nanoparticles are characterized with a wide variety of applications and are mass-produced throughout the world. However, questions remain regarding their safety. There has been paucity of toxicology research on their side effects, especially under in vivo conditions. OBJECTIVES: The present paper aims at evaluating the toxicity of administering 10-15 nm magnesium oxide nanoparticles to Wistar rat under in vivo conditions. In addition, hematology, biochemistry, and histopathology of the rats are examined at various concentrations (62.5-125-250-500 µg.mL-1) over 28-days period. MATERIALS AND METHODS: In this study, 35 male Wistar rats were randomly divided into five groups, comprising one control group and four experimental groups, assigned to various doses of MgO nanoparticles by intraperitoneal injection. Eventually, blood samples were collected, and all animals were sacrificed for liver and kidney tissue investigation. RESULTS: The findings showed that high concentrations of Magnesium oxide nanoparticles (250 and 500 µg.mL-1) significantly increased white blood cells, red blood cells, hemoglobin, and hematocrit compared with the control group (P < 0.05). Moreover, the nanoparticles elevated the levels of aspartate aminotransferase and alkaline phosphatase, whereas no significant difference in levels of alanine aminotransferase, gamma-glutamyl transpeptidase, urea, and creatinine were recorded in comparison with the control group (P < 0.05). Histopathological examinations in the rat's liver showed proliferation of bile ductules, congestion in some regions of the liver sinusoids, and apoptotic cells (probably) in high-dose groups, but no histological changes were found in the kidney functions. CONCLUSIONS: The results from the present study showed that the magnesium oxide nanoparticles in concentrations lower than 250 µg.mL-1 are safe for desired applications.

2.
Mikrochim Acta ; 186(8): 540, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31317272

RESUMO

The authors have modified a carbon paste electrode with Al2O3-supported palladium nanoparticles (PdNP@Al2O3) to obtain a sensor for simultaneous voltammetric determination of melatonin (MT), dopamine (DA) and acetaminophen (AC). The PdNP@Al2O3 was characterized by scanning electron microscopy and energy-dispersive X-ray spectra. The sensor can detect DA, AC, MT and their mixtures by giving distinct signals at working voltages of typically 236, 480 and 650 mV (vs. Ag/AgCl), respectively. Differential pulse voltammetric peak currents of DA, AC and MT increase linearly in the 50 nmol L-1 - 1.45 mmol L-1, 40 nmol L-1 -1.4 mmol L-1, and 6.0 nmol L-1 - 1.4 mmol L-1 concentration ranges. The limits of detection are 36.5 nmol L-1 for DA, 36.5 nmol L-1 for AC, and 21.6 nmol L-1 for MT. The sensor was successfully used to detect the analytes in (spiked) human serum and drug samples. Graphical abstract Schematic presentation of Al2O3-supported palladium nanoparticles (PdNP@Al2O3) for modification of a carbon paste electrode (CPE) to develop a voltammetric sensor for the simultaneous determination of dopamine (DA), acetaminophen (AC) and melatonin (MT).


Assuntos
Acetaminofen/análise , Óxido de Alumínio/química , Dopamina/análise , Melatonina/análise , Nanopartículas Metálicas/química , Paládio/química , Acetaminofen/sangue , Acetaminofen/química , Acetaminofen/urina , Carbono/química , Dopamina/sangue , Dopamina/química , Dopamina/urina , Técnicas Eletroquímicas , Eletrodos , Humanos , Melatonina/sangue , Melatonina/química , Melatonina/urina
3.
IET Nanobiotechnol ; 13(4): 449-455, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31171751

RESUMO

In the first section of this research, superparamagnetic nanoparticles (NPs) (Fe3O4) modified with hydroxyapatite (HAP) and zirconium oxide (ZrO2) and thereby Fe3O4/HAP and Fe3O4/ZrO2 NPs were synthesised through co-precipitation method. Then Fe3O4/HAP and Fe3O4/ZrO2 NPs characterised with various techniques such as X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis, Brunauer-Emmett-Teller, Fourier transform infrared, and vibrating sample magnetometer. Observed results confirmed the successful synthesis of desired NPs. In the second section, the antibacterial activity of synthesised magnetic NPs (MNPs) was investigated. This investigation performed with multiple microbial cultivations on the two bacteria; Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Obtained results proved that although both MNPs have good antibacterial properties, however, Fe3O4/HAP NP has greater antibacterial performance than the other. Based on minimum inhibitory concentration and minimum bactericidal concentration evaluations, S. aureus bacteria are more sensitive to both NPs. These nanocomposites combine the advantages of MNP and antibacterial effects, with distinctive merits including easy preparation, high inactivation capacity, and easy isolation from sample solutions by the application of an external magnetic field.


Assuntos
Antibacterianos/farmacologia , Durapatita/farmacologia , Escherichia coli/efeitos dos fármacos , Nanopartículas de Magnetita/química , Staphylococcus aureus/efeitos dos fármacos , Zircônio/farmacologia , Antibacterianos/química , Durapatita/química , Viabilidade Microbiana/efeitos dos fármacos , Nanocompostos , Zircônio/química
4.
Diabetes Metab Syndr ; 13(5): 3035-3041, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30030156

RESUMO

As a hormone secreted from the pituitary gland, prolactin (PRL) plays an important role in increasing beta cell proliferation, stimulating the secretion of insulin, preventing the activities of caspases on pathways that cause apoptosis in the Langerhans' islands, and moderating the immune system in regulating the whole body's sensitivity to insulin. Therefore, PRL level changes in type II diabetes and it can be concluded that PRL can play an important role in metabolic disorders of glucose. The present study is carried out in order to investigate the association between serum levels of PRL and type II DM. Blood samples were taken from 64 females affected by type II diabetes and 70 healthy ones, whose PRL level was measured using electrochemiluminescence (ECL) technique. It was a case-control study, and based on the definition dedicated to each group, subjects were assigned to two groups. The patient group included the subjects with type II diabetes while the control group included healthy samples. Data were analyzed using SPSS software (Mann-Whitney test, t-test, and spearman's rho correlation test). According to the results, PRL concentration in the serum of people affected by type II diabetes (5.32 ±â€¯0.36) was significantly (P˂0.05) lower than that of control group (18.38 ±â€¯2.3). The results also showed that in type II diabetes, the level of PRL changes so that the concentration of PRL in the serum of the patients was lower than that of healthy ones. Therefore, PRL concentration in the blood can be related to diabetes.


Assuntos
Biomarcadores/sangue , Diabetes Mellitus Tipo 2/sangue , Prolactina/sangue , Idoso , Glicemia/análise , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Irã (Geográfico)/epidemiologia , Prognóstico
5.
Mikrochim Acta ; 185(10): 479, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30259140

RESUMO

A highly selective electrochemical sensor was fabricated based on a modified carbon paste electrode with zinc ferrite nanoparticles (ZnFe2O4 NPs). The nanocomposite has attractive properties such as high surface-to-volume ratio and good electrocatalytic activity towards the drugs acetaminophen (AC), epinephrine (EP), and melatonin (MT), best at working voltages of 0.35, 0.09 and 0.55 V (vs. Ag/AgCl), respectively. The linear ranges (and detection limits) are 6.5-135 (0.4) µmol L-1 for AC, 5-100 (0.7) µmol L-1 for EP, and 6.5-145 (3) µmol L-1 for MT. Graphical abstract A novel electrochemical sensor based on a modified carbon paste electrode with zinc ferrite nanoparticles (ZnFe2O4) for the simultaneous detection of the acetaminophen, epinephrine and melatonin was fabricated.


Assuntos
Acetaminofen/análise , Carbono/química , Eletroquímica/instrumentação , Epinefrina/análise , Compostos Férricos/química , Melatonina/análise , Nanopartículas/química , Compostos de Zinco/química , Eletrodos , Pomadas , Fatores de Tempo
7.
Food Chem Toxicol ; 113: 204-210, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29407473

RESUMO

The current study was undertaken to determine the concentration of Hg and Pb in ten types of collected green leafy vegetables and herbs from different agricultural sites of Markazi province, Iran as well as the gathered water and soil around them using inductively coupled plasma-optical emission spectroscopy (ICP-OES). Also, the potential health risk assessment by using target hazard quotient (THQ) and hazard index (HI) parameters was estimated. Based on the accumulation order, Artemisia dracunculus L with 56.147 ±â€¯17.30 µg/kg and Spinacia oleracea L with 1733.62 ±â€¯2264.7 µg/kg can uptake and accumulate more concentration of Pb and Hg in their tissues, respectively. Regarding gathered soil around vegetables, the concentration of Hg and Pb were measured as 52.056 ±â€¯16.25 µg/kg and 4993.83 ±â€¯1287.8 µg/kg, respectively. The transfer factor (TF) demonstrated that vegetables and herbs could absorb a high amount of Hg from the soil while these plants uptake less concentration of Pb thought their green leaves. The non-carcinogenic risk assessment showed the minimum, and maximum THQ was related to 15-24 and 35-44 age groups in the urban and rural consumers. Also, HI in the urban and rural areas was calculated as 8.492 and 9.012, respectively. Since HI > 1, exposure of the urban and rural areas of Markazi province to non-carcinogenic risk by consuming the green leafy vegetables and herbs is a source of concern.


Assuntos
Exposição Dietética , Chumbo/análise , Mercúrio/análise , Verduras/química , Adolescente , Adulto , Calibragem , Carcinógenos , Feminino , Contaminação de Alimentos/análise , Humanos , Irã (Geográfico) , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Medição de Risco , População Rural , Poluentes do Solo/análise , Análise Espectral/métodos , População Urbana , Poluentes Químicos da Água/análise , Adulto Jovem
8.
Int J Biol Macromol ; 93(Pt A): 254-266, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27238586

RESUMO

In the present study, a series of chitosan/Zeolite Y/Nano Zirconium oxide (CTS/ZY/Nano ZrO2) nanocomposites were made by controlling the molar ratio of chitosan (CTS) to Zeolite Y/Nano Zirconium oxide in order to remove nitrate (NO3-) ions in the aqueous solution. The nanocomposite adsorbents were characterized by XRD, FTIR, BET, SEM and TEM. The influence of different molar ratios of CTS to ZY/Nano ZrO2, the initial pH value of the nitrate solution, contact time, temperature, the initial concentration of nitrate and adsorbent dose was studied. The adsorption isotherms and kinetics were also analyzed. It was attempted to describe the sorption processes by the Langmuir equation and the theoretical adsorption capacity (Q0) was found to be 23.58mg nitrate per g of the adsorbent. The optimal conditions for nitrate removal were found to be: molar ratio of CTS/ZY/Nano ZrO2: 5:1; pH: 3; 0.02g of adsorbent and temperature: 35°C, for 60min. The adsorption capacities of CTS, ZY, Nano ZrO2, CTS/Nano ZrO2, CTS/ZY and CTS/ZY/Nano ZrO2 nanocomposites for nitrate removal were compared, showing that the adsorption ability of CTS/ZY/Nano ZrO2 nanocomposite was higher than the average values of those of CTS (1.95mg/g for nitrate removal), ZY, Nano ZrO2, CTS/Nano ZrO2, and CTS/ZY.


Assuntos
Quitosana/química , Nanocompostos/química , Nitratos/química , Nitratos/isolamento & purificação , Zeolitas/química , Zircônio/química , Adsorção , Cinética , Soluções , Temperatura , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água
9.
J Pharm Biomed Anal ; 121: 123-134, 2016 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-26802527

RESUMO

In the present study, an efficient and environmental friendly method (called in-syringe reversed dispersive liquid-liquid microextraction (IS-R-DLLME)) was developed to extract three important components (i.e. para-anisaldehyde, trans-anethole and its isomer estragole) simultaneously in different plant extracts (basil, fennel and tarragon), human plasma and urine samples prior their determination using high-performance liquid chromatography. The importance of choosing these plant extracts as samples is emanating from the dual roles of their bioactive compounds (trans-anethole and estragole), which can alter positively or negatively different cellular processes, and necessity to a simple and efficient method for extraction and sensitive determination of these compounds in the mentioned samples. Under the optimum conditions (including extraction solvent: 120 µL of n-octanol; dispersive solvent: 600 µL of acetone; collecting solvent: 1000 µL of acetone, sample pH 3; with no salt), limits of detection (LODs), linear dynamic ranges (LDRs) and recoveries (R) were 79-81 ng mL(-1), 0.26-6.9 µg mL(-1) and 94.1-99.9%, respectively. The obtained results showed that the IS-R-DLLME was a simple, fast and sensitive method with low level consumption of extraction solvent which provides high recovery under the optimum conditions. The present method was applied to investigate the absorption amounts of the mentioned analytes through the determination of the analytes before (in the plant extracts) and after (in the human plasma and urine samples) the consumption which can determine the toxicity levels of the analytes (on the basis of their dosages) in the extracts.


Assuntos
Artemisia/química , Foeniculum/química , Microextração em Fase Líquida/métodos , Ocimum basilicum/química , Plasma/química , Urina/química , Derivados de Alilbenzenos , Anisóis/sangue , Anisóis/química , Anisóis/urina , Benzaldeídos/sangue , Benzaldeídos/química , Benzaldeídos/urina , Humanos , Limite de Detecção , Solventes/química , Seringas
10.
Ultrason Sonochem ; 19(3): 546-53, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21986517

RESUMO

Polyoxometalates (POM) supported on zirconia, H(3)PW(12)O(40)/ZrO2, were prepared by incorporating polyphosphotungstate into a zirconia matrix via sol-gel technique that involving the hydrolysis of zirconium (IV) n-butoxide, Zr (n-OBu)(4), as the ZrO(2) source. This insoluble and readily separable catalyst was characterized by using XRD, FT-IR, SEM, and UV diffuse reflectance spectroscopy (UV-DRS), indicating that the polyphosphotungstate was chemically attached to the zirconia supports, and primary Keggin structure remained intact. The photocatalytic and sonocatalytic activity of the supported polyphosphotungstate was tested via degradation of different dyes in aqueous solutions. The POM-ZrO(2) nanocomposite showed higher photocatalytic and sonocatalytic activity than pure polyoxometalate or pure ZrO(2).


Assuntos
Corantes/química , Corantes/efeitos da radiação , Ácido Fosfotúngstico/química , Ácido Fosfotúngstico/efeitos da radiação , Sonicação/métodos , Zircônio/química , Zircônio/efeitos da radiação , Catálise/efeitos da radiação , Ondas de Choque de Alta Energia , Doses de Radiação , Raios Ultravioleta , Água/química
11.
Ultrason Sonochem ; 17(2): 453-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19879792

RESUMO

A Keggin type polyoxometalate (POM) has been immobilized in the unique network structure of multi-wall carbon nanotubes (CNTs). The vanadium-containing polyphosphomolybdate (PVMo) supported on CNTs, which was prepared by a one-step solid-state reaction, was characterized by FT-IR, XRD, SEM and elemental analyses. These uniform nanoparticles have an average size 20-30nm. Furthermore, due to the chemical interaction between PVMo and carboxylic acid groups, PVMo nanoparticles were successfully immobilized on the CNTs. Moreover, the obtained composite was found as an efficient catalyst for oxidation of hydrocarbons under reflux and ultrasonic irradiation (US) conditions.


Assuntos
Química/métodos , Compostos de Epóxi/química , Molibdênio/química , Nanotecnologia/métodos , Nanotubos de Carbono/química , Ácidos Fosfóricos/química , Ultrassom , Vanádio/química , Alcenos/química , Catálise , Química Orgânica/métodos , Hidrocarbonetos/química , Peróxido de Hidrogênio/química , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
12.
Ultrason Sonochem ; 17(1): 145-52, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19535281

RESUMO

A Keggin-type heteropolyanion compound (HPO) was doped within the montmorillonite (MMT) structure by impregnation method. The synthesized catalyst was characterized by FT-IR, XRD, UV-vis, CV, SEM and elemental analysis. Based on chemical adsorption between HPO, and hydroxyl surface groups, HPOs nanoparticles were successfully located on the MMT. Moreover, the obtained nanocomposite was found as an efficient catalyst for oxidation of hydrocarbons under reflux and ultrasonic irradiation conditions.


Assuntos
Alcenos/química , Alcenos/efeitos da radiação , Bentonita/química , Bentonita/efeitos da radiação , Nanoestruturas/química , Nanoestruturas/efeitos da radiação , Sonicação/métodos , Ânions , Catálise , Nanoestruturas/ultraestrutura , Oxirredução/efeitos da radiação , Tamanho da Partícula , Doses de Radiação
13.
Ultrason Sonochem ; 15(5): 815-22, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18083055

RESUMO

Na5PV2Mo10O40 supported on nanoporous anatase TiO2 particles, TiO2-PVMo, was used as an efficient photocatalyst for photocatalytic degradation of different dyes by visible light using oxygen as oxidant. This catalyst showed a good catalytic activity in the sonocatalytic and sonophotocatalytic decomposition of different dyes in aqueous solutions. The TiO2-PVMo composite showed higher photocatalytic and sonocatalytic activity than pure polyoxometalate or pure TiO2.

14.
Ultrason Sonochem ; 15(4): 438-447, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17692553

RESUMO

Vanadium polyoxometalate (PVMo) supported on mesoporous MCM-41, MCM-41-NH(2), as efficient and heterogeneous catalysts, with large surface area, for hydrocarbon oxidation with hydrogen peroxide is reported. Oxidation of the alkenes and alkanes gave product selectivities, which are similar to those observed for corresponding homogeneous catalyst. PVMo-MCM was prepared by introduction of PVMo into the mesoporous molecule sieves of MCM-41 by impregnation and adsorption techniques. The samples were characterized by X-ray diffraction (XRD), thermal gravimetric-differential thermal analysis (TG-DTA), FT-IR, scanning electron microscopy (SEM), UV-Vis and cyclic voltametry (CV). Ultrasonic irradiation has a particular effect on MCM-41 structural uniformity and reduced the reaction times and improved the product yields. In addition, the solid catalysts could be recovered and reused several times without loss of its activity.


Assuntos
Hidrocarbonetos/química , Hidrocarbonetos/efeitos da radiação , Dióxido de Silício/química , Vanádio/química , Alcanos/química , Alcanos/efeitos da radiação , Alcenos/química , Alcenos/efeitos da radiação , Catálise , Peróxido de Hidrogênio , Hidroxilação , Microscopia Eletrônica de Varredura , Oxirredução , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos de Tungstênio/química , Ultrassom
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