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1.
Environ Res ; 219: 114995, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36529324

RESUMEN

A crucial problem that needs to be resolved is the sensitive and selective monitoring of chlorophenol compounds, especifically 4-chlorophenol (4-CP), one of the most frequently used organic industrial chemicals. In light of this, the goal of this study was to synthesize Fe3O4 incorporated cellulose nanofiber composite (Fe3O4/CNF) as an amplifier in the development of a modified carbon paste electrode (CPE) for 4-CP detection. Transmission electron microscopy (TEM) was used to evaluate the morphology of the synthesized nanocatalyst, while differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS), and linear sweep voltammetry (LSV) techniques were implemented to illuminate the electrochemical characteristics of the fabricated sensor. The ultimate electrochemical sensor (Fe3O4/CNF/CPE) was used as a potent electrochemical sensor for monitoring 4-CP in the concentration range of 1.0 nM-170 µM with a limit of detection value of 0.5 nM. As a result of optimization studies, 8.0 mg Fe3O4/CNF was found to be the ideal catalyst concentration, whereas pH = 6.0 was chosen as the ideal pH. The 4-CP's oxidation current was found to be over 1.67 times greater at ideal operating conditions than it was at the surface of bare CPE, and its oxidation potential decreased by about 120 mV. By using the standard addition procedure on samples of drinking water and wastewater, the suggested capability of Fe3O4/CNF/CPE to detect 4-CP was further investigated. The recovery range was found to be 98.52-103.66%. This study paves the way for the customization of advanced nanostructure for the application in electrochemical sensors resulting in beneficial environmental impact and enhancing human health.


Asunto(s)
Clorofenoles , Nanofibras , Contaminantes del Agua , Humanos , Carbono/química , Celulosa , Técnicas Electroquímicas/métodos , Electrodos
2.
Environ Res ; 195: 110809, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33515581

RESUMEN

In the present study, a novel 1-butyl-3-methylimidazolium bromide (BmImBr) impregnated chitosan beads were prepared and characterized using different methods, including XRD, FT-IR, EDX, SEM and BET. The FTIR analysis revealed that the BmImBr was successfully conjugated with the chitosan in the beads structure. The prepared beads were used as an efficient sorbent for the fast removal of methylene blue, as cationic dye model, from aqueous solution, whereas just 25 min was required to reach 86% removal efficiency. The increasing of BmImBr amount improved the adsorption performance of prepared beads. Also, it was found that the dye can be higher adsorbed on the beads surface by increasing the sorbent dosage and pH of solution, while the optimum dosage and pH were obtained 3 mg/L and 11, respectively. The kinetic study showed that the MB adsorption onto the CS-BmImBr beads follows the pseudo-fist order model and the intrinsic penetration controls the adsorption process. The properties of prepared chitosan- BmImBr IL conjugation confirmed that it can be exploited as an efficient adsorbent in the wastewater treatment.


Asunto(s)
Quitosano , Nanoestructuras , Contaminantes Químicos del Agua , Adsorción , Hidrogeles , Concentración de Iones de Hidrógeno , Imidazoles , Cinética , Espectroscopía Infrarroja por Transformada de Fourier
3.
Chem Rec ; 20(7): 682-692, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31845511

RESUMEN

Analysis of food, pharmaceutical, and environmental compounds is an inevitable issue to evaluate quality of the compounds used in human life. Quality of drinking water, food products, and pharmaceutical compounds is directly associated with human health. Presence of forbidden additives in food products, toxic compounds in water samples and drugs with low quality lead to important problems for human health. Therefore, attention to analytical strategy for investigation of quality of food, pharmaceutical, and environmental compounds and monitoring presence of forbidden compounds in materials used by humans has increased in recent years. Analytical methods help to identify and quantify both permissible and unauthorized compounds present in the materials used in human daily life. Among analytical methods, electrochemical methods have been shown to have more advantages compared to other analytical methods due to their portability and low cost. Most of big companies have applied this type of analytical methods because of their fast and selective analysis. Due to simple operation and high diversity of electroanalytical sensors, these types of sensors are expected to be the future generation of analytical systems. Therefore, many scientists and researchers have focused on designing and fabrication of electroanalytical sensors with good selectivity and high sensitivity for different types of compounds such as drugs, food, and environmental pollutants. In this paper, we described the mechanism and different examples of DNA, enzymatic and electro-catalytic methods for electroanalytical determination of drug, food and environmental compounds.


Asunto(s)
Técnicas Biosensibles , Contaminación de Medicamentos , Técnicas Electroquímicas , Contaminantes Ambientales/análisis , Contaminación de Alimentos/análisis , Humanos
4.
Parasitol Res ; 119(12): 4233-4241, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32996050

RESUMEN

Albendazole is known as the drug of choice for medical treatment of cystic echinococcosis (CE). Albendazole sulfoxide (ABZ-SO), as the main active metabolite of albendazole, has low efficacy in the disease due to low water solubility and poor absorptivity. PLGA nanoparticles (NPs) enhance the dissolution of poorly soluble drugs, and chitosan (CS) coating enhances oral drug delivery of NPs. In this study, the efficacy of ABZ-SO-loaded CS-PGLA NPs in the treatment of CE was evaluated in laboratory mice. ABZ-SO-loaded CS-PGLA NPs were prepared by nanoprecipitation and characterized by dynamic light scattering method and scanning electron microscopy. Thirty mice were intraperitoneally infected by 1000 protoscoleces of Echinococcus granulosus. Ten months later, the mice were allocated into 3 groups: groups 1 and 2 were treated with ABZ-SO and ABZ-SO-loaded CS-PGLA NPs, respectively, and the mice in group 3 remained untreated as the control group. The drugs were administered by gavage for 45 days at a daily dose of 10 mg/kg. Finally, all mice were opened and the cysts were collected, counted, weighed, and measured separately. The therapeutic effect of ABZ-SO in the number, weight, and volume of the cysts were not statistically significant compared with those in ABZ-SO-loaded CS-PGLA NPs and the control group. However, the therapeutic effect of ABZ-SO-loaded CS-PGLA NPs in the weight and volume of cysts were statistically significant when compared with that in the control group (p ˂ 0.05). In conclusions, this study revealed that ABZ-SO-loaded CS-PGLA NPs could enhance the therapeutic efficacy of ABZ-SO in the treatment of CE in laboratory mice.


Asunto(s)
Albendazol/análogos & derivados , Antiplatelmínticos/administración & dosificación , Quitosano/química , Equinococosis/tratamiento farmacológico , Ácido Poliglicólico/química , Administración Oral , Albendazol/administración & dosificación , Albendazol/química , Animales , Antiplatelmínticos/química , Quitosano/administración & dosificación , Sistemas de Liberación de Medicamentos , Evaluación Preclínica de Medicamentos , Echinococcus granulosus/efectos de los fármacos , Ratones , Nanopartículas/administración & dosificación , Nanopartículas/química , Ácido Poliglicólico/administración & dosificación
5.
J Invertebr Pathol ; 168: 107254, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31654675

RESUMEN

The insecticidal activity and effects of sublethal combinations of the fungus, Beauveria bassiana-IRAN441C and commercial diatomaceous earth (DE) were assessed on adult coleopterans, Callosobruchus maculatus (F.) (Chrysomelidae), and Oryzaephilus surinamensis (L.) (Silvanidae). Dry conidia and DE were applied singly or in combination. The agents produced acceptable mortality, however, results were not affected by species of host plant seeds fed to the beetles. F1 progeny reduction was notably increased in both beetle species when mixtures of the fungus and DE were each at the LC50 level. In addition to avoidance behavior, different combinations of fungus/DE dosages induced winged morphs (non-reproductive phase) in the C. maculatus population after 50 d exposure. Our results demonstrated that a combination of B. bassiana and DE resulted in high mortality of both beetle species and co-application of B. bassiana and DE is feasible in a stored product pest management program.


Asunto(s)
Beauveria/patogenicidad , Escarabajos/microbiología , Tierra de Diatomeas/farmacología , Animales , Escarabajos/efectos de los fármacos , Composición de Medicamentos , Fertilidad , Microbiología de Alimentos , Almacenamiento de Alimentos , Insecticidas/química , Insecticidas/farmacología , Dosificación Letal Mediana , Mortalidad , Control Biológico de Vectores/métodos , Esporas Fúngicas/patogenicidad
6.
J Invertebr Pathol ; 158: 32-42, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30145233

RESUMEN

We assessed the effects of exposure of the cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) larvae to the entomopathogenic fungus Beauveria bassiana (isolate DC2) on life history parameters of the subsequent generation. Mortality assays against second instar larvae showed B. bassiana isolates to be significantly virulent, causing high mortality. Life history parameters such as developmental time, fecundity and survivorship were affected in the offspring of survivors of exposure to LC25 and LC50 concentrations of B. bassiana DC2. Pre-adult duration of H. armigera was significantly extended and total longevity and female progeny fecundity were decreased. Oviposition duration was shortened compared to offspring of untreated controls. All population parameters including intrinsic (r) and finite (λ) rates of increase and net (R0) and gross (GRR) reproductive rates were significantly decreased in offspring derived from H. armigera larvae treated with B. bassiana DC2. The intrinsic rate of increase (r) was 0.198 d-1, 0.120 d-1 and 0.111 d-1, respectively, for the F1 generation of controls (untreated), LC25- and LC50-treated cotton bollworm. The morphogenetic effects of B. bassiana observed due to the indirect effect of sub-lethal concentrations included abnormal pupae and adults and mortality resulted from the malformations. Pupal weight was reduced in offspring of treated individuals but sex ratios did not differ. Our results revealed that B. bassiana increased fitness costs of H. armigera in both direct (mortality) and indirect (disruption of normal development) ways. Adverse effects of sub-lethal fungal treatments on the parent generation carried over to the next generation.


Asunto(s)
Beauveria/fisiología , Interacciones Huésped-Parásitos/fisiología , Lepidópteros/parasitología , Animales , Control Biológico de Vectores/métodos
7.
Sci Rep ; 14(1): 9387, 2024 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-38653765

RESUMEN

The study aimed to compare various toothpastes and mouthwashes on permanent tooth dentin after erosive and abrasive challenges. 130 sound premolars dentin were randomly submitted to an initial erosive challenge and a cycle of erosive and abrasive challenges for five days. The five experimental groups (n = 26) were: (1) Control group (artificial saliva), (2) Elmex erosion protection toothpaste and mouthwash, (3) Vitis anticaries biorepair toothpaste and mouthwash, (4) Oral B Pro-expert toothpaste and Oral B Fluorinse mouthwash, and (5) MI Paste ONE toothpaste and Caphosol mouthwash. Microhardness, surface roughness values, and the topographical characteristics of the dentin surface were assessed. The highest percentage of recovered dentin microhardness (%RDMH) value was observed in groups 2 and 4, followed by groups 5 and 3, respectively. The %RDMH values in groups 2 and 4 did not demonstrate a significant difference (p = 0.855). The highest percentage of improvement in surface roughness was recorded in groups 2 and 4, with no significant differences (p = 0.989). The atomic force microscopy (AFM) findings were consistent with the surface roughness data. The best recovery of dentin microhardness and roughness were measured with the Elmex and Oral B toothpaste and mouthwash, followed by MI Paste ONE toothpaste and Caphosol mouthwash and Vitis anticaries biorepair toothpaste and mouthwash.


Asunto(s)
Dentina , Antisépticos Bucales , Erosión de los Dientes , Pastas de Dientes , Pastas de Dientes/farmacología , Antisépticos Bucales/farmacología , Humanos , Dentina/efectos de los fármacos , Erosión de los Dientes/prevención & control , Propiedades de Superficie , Dureza , Técnicas In Vitro
8.
J Hazard Mater ; 423(Pt A): 127058, 2022 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-34488091

RESUMEN

Cyanazine is a beneficial herbicide in the triazines group that inhibits photosynthesis in plants and monitoring of this herbicide is so important for study agriculture products. The present researches have been focused on monitoring of cyanazine by a straightforward and fast electrochemical strategy. Herein, to monitor the cyanazine level, Pt and Pd doped CdO nanoparticle decorated SWCNTs composite (Pt-Pd-CdO/SWCNTs) has been synthesized as a conductive mediator and characterized by EDS, SEM and TEM techniques. The Pt-Pd-CdO/SWCNTs and ds-DNA have been used for modification of the gold electrode (GE). Moreover, the oxidation signal of guanine relative to ds-DNA at the surface of Pt-Pd-CdO/SWCNTs/ds-DNA/GE has been considered as an bioelectroanalytical issue to monitoring cyanazine for the first time. Electrochemical impedance spectroscopic (EIS) signals have confirmed that the inclusion of Pt-Pd-CdO/SWCNTs at the surface of the GE has lowered charge-transfer resistance by ca.1.54 times and created a highly conductive state for monitoring of cyanazine in nanomolar concentration. On the other hand, differential pulse voltammograms (DPV) of Pt-Pd-CdO/SWCNTs/ds-DNA/GE have indicated a linear dynamic range of 4.0 nM-70 µM with a detection limit of 0.8 nM to the monitoring of cyanazine. In addition, the molecular docking study has emphasized that cyanazine herbicide is capable of binding to ds-DNA preferably at the guanine-cytosine rich sequences, and confirmed experimental results. In the final step, Pt-Pd-CdO/SWCNTs/ds-DNA/GE has been successfully utilized for the monitoring of cyanazine herbicide in food and water samples.


Asunto(s)
Técnicas Biosensibles , Herbicidas , Nanopartículas , ADN , Técnicas Electroquímicas , Electrodos , Sustancias Peligrosas , Herbicidas/toxicidad , Simulación del Acoplamiento Molecular , Triazinas
9.
Food Chem Toxicol ; 161: 112830, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35077828

RESUMEN

Ponceau dyes are one of the food coloring materials that are added to various pharmaceutical, health and food products and give them an appearance. These dyes contain contaminants such as Benzidine, 4-Aminobiphenyl, and 4-Aminoazobenzene that are safe in small amounts, but they are not approved by the US Food and Drug Administration (US-FDA) for human consumption. This study comprehensively was reviewed the properties, applications, chemistry, and toxicity of Ponceau dyes as food colorant substances. Electroanalysis of Ponceau dyes was discussed in detail, and the various electrochemical sensors used to detect and monitor these dyes as food colorant were examined. The applied methods of removing and degradation of these dyes in municipal and industrial wastes were also discussed. Conclusions and future perspectives to motivate future research were also explored.


Asunto(s)
Compuestos Azo/química , Técnicas Electroquímicas/instrumentación , Colorantes de Alimentos/química , Análisis de los Alimentos , Contaminación de Alimentos , Humanos , Estructura Molecular , Oxidación-Reducción
10.
Food Chem Toxicol ; 164: 113053, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35460823

RESUMEN

Analysis of protein content of food is necessary for quality control and is essential for precise labeling. Protein analysis is an issue of great economic and social fondness. Cereals are one of the most important sources of protein in food, livestock and poultry feed. In this article, the technique of extracting protein in 4 types of grains and measuring it by the Bradford method is discussed. The results obtained from this method are compared with the data obtained by the Kjeldahl method. This comparison showed that the Bradford method is more accurate in measuring proteins. Extraction of protein using NaOH at pH 13 can be used as a modified method to release proteins in soybean meal and consequently a Fast and accurate high-performance laboratory determination method for protein content via the Bradford method. The optimum pH value was identified as that of 13 in optimum temperature 40 °C for maximum protein extraction yield (43.6%, w/w). The new method used in this paper has resulted in the measurement of grain protein in the shortest time and with the least toxicity and the highest accuracy.


Asunto(s)
Glycine max , Semillas , Grano Comestible/química , Proteínas , Semillas/química
11.
Food Chem Toxicol ; 162: 112907, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35271984

RESUMEN

Synthetic azo dyes are widely used in a variety of industries, but many of them pose a risk to human health, particularly when consumed in large quantities. As a result, their existence in products should be closely monitored. D&C red 33 and Patent Blue V are mostly used in cosmetics, especially in toothpaste and mouthwashes. A novel carbon paste electrode modified with ZIF-8/g-C3N4/Co nanocomposite and 1-methyl-3-butylimidazolium bromide as an ionic liquid was employed as a highly sensitive reproducible electrochemical sensor for the simultaneous determination of these common dyes. ZIF structure has unique properties such as high surface area, suitable conductivity, and excellent porosity. The electrochemical behavior of the suggested electrode was investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). To characterize the synthesized nanocomposites, scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were applied to investigate the structure of nanocomposites. Under the optimized conditions, the modified sensor offered a wide linear concentration range 0.08-10 µM (R2 = 0.9906) and 10-900 µM (R2 = 0.9932) with a low limit of detection of 0.034 µM. The value of diffusion coefficient (D), and the electron transfer coefficient (α) was calculated to be 310 × 10-5, and 0.9 respectively. This technique offered a successful performance for the determination of target analyte in the real samples with acceptable results between 96% and 107%.

12.
Food Chem Toxicol ; 165: 113075, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35487338

RESUMEN

Brown HT and carmoisine, which are the most used dyestuffs in pharmaceuticals, textiles, cosmetics and foods, are important components of the Azo family. Although the Azo group is not toxic or carcinogenic under normal conditions, these dyestuffs require great care due to the reduction of the Azo functional group to amines. In particular, fast, reliable, easy, on-site and precise determinations of these substances are extremely necessary and important. In this review, the properties, applications, and electrochemical determinations of brown HT and carmoisine, which are used as synthetic food colorants, are discussed in detail. Up to now, sensor types, detection limits (LOD and LOQ), and analytical applications in the developed electrochemical strategies for both substances were compared. In addition, the validation parameters such as the variety of the sensors, sensitivity, selectivity and electrochemical technique in these studies were clarified one by one. While the electrochemical techniques recommended for brown HT were mostly used for the removal of dyestuff, for carmoisine they included fully quantitative centered studies. The percentiles of voltammetric techniques, which are the most widely used among these electroanalytical methods, were determined. The benefits of a robust electrochemical strategy for the determination of both food colors are summed up in this review. Finally, the brown HT and carmoisine suggestions for future perspectives in electrochemical strategy are given according to all their applications.


Asunto(s)
Colorantes de Alimentos , Naftalenosulfonatos , Compuestos Azo , Técnicas Electroquímicas , Naftalenosulfonatos/química
13.
Poult Sci ; 101(3): 101652, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35038649

RESUMEN

Clostridium perfringens-induced necrotic enteritis (NE) is an economically important disease of broiler chickens. The present study evaluated the effect of C. perfringens on the intestinal histomorphometry, enteric microbial colonization, and host immune responses using 3 experimental NE reproduction methods. The experimental groups consisted of 1) unchallenged Control diet (corn-soybean meal), 2) Control diet + Eimera inoculation at d 11 followed by C. perfringens challenge at d 15 (ECp), 3) Wheat-based diet + C. perfringens challenge (WCp), and 4) Wheat-based diet + Eimeria inoculation followed by C. perfringens challenge (WECp). The results showed that chickens receiving ECp and WECp had reduced (P < 0.05) bird performance coupled with enteric gross lesions and epithelial damage at d 17 and 24 of age compared to unchallenged control birds. These ECp and WECp administered birds also had increased (P < 0.05) ileal colonization by clostridia and E. coli at d 17 and 24, while the resident Lactobacillus counts were reduced (P < 0.05) at d 24 of age. Furthermore, at d 24, jejunal transcription of IL-6, IL-10, annexin-A1 and IL-2 genes was upregulated (P < 0.05) in the ECp group, whereas the transcription of TNF receptor associated factor (TRAF)-3 gene was increased (P < 0.05) in WECp treated birds when compared to unchallenged control group. Additionally, stimulation of chicken splenocytes and cecal tonsilocytes with virulent C. perfringens bacilli or their secretory proteins resulted in a higher (P < 0.05) frequency of T cells and their upregulation of MHC-II molecule, as determined by flow cytometry. These findings suggest that C. perfringens, while inducing epithelial damage and changes in microbiota, can also trigger host immune responses. Furthermore, NE reproduction methods using coccidia with or without the wheat-based dietary predisposition seem to facilitate an optimal NE reproduction in broiler chickens and thus, may provide better avenues for future C. perfringens research.


Asunto(s)
Infecciones por Clostridium , Enteritis , Enfermedades de las Aves de Corral , Animales , Pollos , Infecciones por Clostridium/patología , Infecciones por Clostridium/veterinaria , Clostridium perfringens/fisiología , Dieta/veterinaria , Enteritis/patología , Enteritis/veterinaria , Escherichia coli , Inmunidad , Necrosis/veterinaria
14.
Food Chem Toxicol ; 163: 112929, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35307455

RESUMEN

This study provides a comprehensive review of the latest developments in the electrochemical impressions of the important dyestuffs including amaranth and carminic acid. Food colors are organic substances that have important effects on human health and food safety. While these substances do not pose a problem when used in the daily intake (ADI) amounts, they harm human health when consumed excessively. Amaranth and carminic acid are synthetic and natural food colors ingredients, respectively. Analysis of these substances in food, pharmaceutical, cosmetic and textile samples is extremely important because of their genotoxicity, cytostatic and cytotoxic effects. Electroanalytical methods, which have great advantages over traditional analytical methods, shed light on the scientific world. Electrochemical monitoring modules, which are fast, simple, accurate, reliable, and highly selective, are promising for the determination of both substances. Until now, amaranth and carminic acid food determinations have been carried out successfully with electrochemical monitoring techniques in many numbers in the literature. Voltammetric techniques are the most widely used among these electroanalytical methods. In particular, square wave and differential pulse voltammetric techniques, which have extraordinary properties, have been heavily preferred. Limits of detection (LOD) comparable to the standard analytical method have been achieved using these methods, which have very quick analysis durations, high precision and accuracy, do not require long preprocessing, and have great selectivity. In addition, more sensitive and selective analyses of amaranth and carminic acid in natural samples were carried out with numerous indicator electrodes. The merits of powerful electrochemical monitoring studies for the determination of both food colors during the last decade are presented in this study. Moreover, parameters such as analytical applications, detection limits, electrochemical methods, selectivity, working electrodes, and working ranges are summarized in detail.


Asunto(s)
Carmín , Colorantes de Alimentos , Colorante de Amaranto , Técnicas Electroquímicas/métodos , Electrodos , Humanos
15.
Chemosphere ; 294: 133800, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35101429

RESUMEN

Numerous people suffer from accidental or deliberate exposure to different pesticides when poisoning with aluminum phosphate (AlP) is increasing in the eastern countries. Aluminum phosphate is a conventional insecticide that quickly reacts with water or the moistures in the atmosphere and produces fatal phosphine gas, which absorbs quickly by the body. Oral consumption or inhalation of AlP leads to excessive reaction of the body such as fatigue, vomiting, fever, palpitation, vasodilatory shock, increasing blood pressure, cardiac dysfunction, pulmonary congestion, shortness of breath, and death. The garlic smell from the patient's mouth or exhale is one of the methods to recognize the positioning. Due to the lack of individual antidotes, several supportive treatments are required. The present study focused on the available and new therapies that help reduce the effect of AlP poisoning and the mortality rate. The therapies are divided into the antioxidant-related agent and the other agents. The impacts of each agent on the experimental cases are reported.


Asunto(s)
Insecticidas , Intoxicación por Organofosfatos , Plaguicidas , Fosfinas , Intoxicación , Compuestos de Aluminio , Antídotos/uso terapéutico , Humanos , Plaguicidas/toxicidad , Intoxicación/terapia
16.
Chemosphere ; 287(Pt 2): 132187, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34509007

RESUMEN

In this work, we report a novel enzymatic biosensor based on glutathione peroxidase (GSH-Px), graphene oxide (GO) and nafion for the electrochemical sensing of glutathione (GSH) in body fluids. GSH-Px was immobilized covalently via 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) onto modified glassy carbon electrode (GCE) decorated with GO and nafion and successfully used for sensing of GSH in the presence of H2O2 as catalyst with Michaelis-Menten constant about 0.131 mmol/L. The active surface are of GCE improve from 0.183 cm2 to 0.225 cm2 after modification with GO. The introduced biosensor (GSH-Px/GO/nafion/GCE) was used for monitoring of GSH over the range 0.003-370.0 µM, with a detection limit of 1.5 nM using differential pulse voltammetric (DPV) method. The GSH-Px/GO/nafion/GCE was successfully applied to the determination of GSH in real samples.


Asunto(s)
Técnicas Biosensibles , Líquidos Corporales , Glutatión , Grafito , Peróxido de Hidrógeno
17.
J Econ Entomol ; 114(2): 684-693, 2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33479771

RESUMEN

In many cases, pesticides' side effects on natural enemies have closely related to their exposure route. We assessed long-term lethal and sublethal effects of thiamethoxam (TMX) on the predatory bug, Orius albidipennis (Reuter), fed on Aphis gossypii Glover (Hemiptera: Aphididae), through three exposure routes. First-instar nymphs were treated with the maximum field recommended concentration (MFRC), ½ MFRC, and » MFRC of TMX for 24 h. Based on the results, the soil-application treatment (bottom-up effect: plant-aphid-predator) led to the lowest survival reduction. In contrast, leaf-dip (residual contact) and aphid-dip (oral exposure route) treatments decreased the survival severely. While the soil-application treatment had no significant effect on adult longevity and egg production, all tested concentrations of TMX in the leaf-dip and aphid-dip treatments negatively affected both traits. The egg hatchability was not affected by the insecticide in all exposure routes. Among all treatments, » MFRC of TMX in the residual contact and oral treatments shortened the egg incubation period compared to control, but others failed to affect it. Finally, based on the criteria provided by the International Organization for Biological and Integrated Control (IOBC) regarding toxicity classification, systemic (soil) application of TMX was harmless for this predator. However, it was moderately harmful and harmful (depending on concentration) to the predator through the residual contact and oral exposures, even at » MFRC. Given our results, the soil-application of TMX is compatible with O. albidipennis, and it can improve conservation approaches of the predator in the integrated management of A. gossypii.


Asunto(s)
Áfidos , Heterópteros , Insecticidas , Animales , Insecticidas/toxicidad , Conducta Predatoria , Tiametoxam
18.
Nanoscale Res Lett ; 16(1): 144, 2021 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-34529188

RESUMEN

Brucellosis is considered as the most common bacterial zoonosis in the world. Although the laboratory findings are the most reliable diagnosis today, the current laboratory methods have many limitations. This research aimed to design and evaluate the performance of a novel technique based on the localized surface plasmon resonance (LSPR) to eliminate or reduce existing shortcomings. For this purpose, smooth lipopolysaccharides were extracted from Brucella melitensis and Brucella abortus and fixed on the surface of the gold nanoparticles through covalent interactions. After some optimizing processes, dynamic light scattering was used to characterize the probe. The detection of captured anti-Brucella antibody was performed by measuring the redshift on LSPR peak followed by the determination of cutoff value, which indicated a significant difference between controls and true positive patients (P value < 0.01). Furthermore, 40 sera from true negative samples and positive patients were used to evaluate the performance of this method by comparing its outcomes with the gold standard (culture), standard tube agglutination test, and anti-brucellosis IgM and IgG levels (ELISA). The sensitivity, specificity, positive predictive value, and negative predictive value showed an appropriate performance of the LSPR-based method (85%, 100%, 100%, and 86%, respectively). The current research results provide a promising fast, convenient, and inexpensive method for detecting the anti-Brucella antibodies in human sera, which can be widely used in medical laboratories to diagnose brucellosis quickly and effectively.

19.
J Biomed Phys Eng ; 11(2): 229-238, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33937129

RESUMEN

BACKGROUND: Ionizing radiation plays a significant role in cancer treatment. Despite recent advances in radiotherapy approaches, the existence of irradiation-resistant cancer cells is still a noteworthy challenge. Therefore, developing novel therapeutic approaches are still warranted in order to increase the sensitivity of tumor cells to radiation. Many types of research rely on the role of mitochondria in radiation protection. OBJECTIVE: Here, we aimed to target the mitochondria of monocyticleukemia (THP-1) radio-resistant cell line cells by a mitochondrial disrupting peptide, D (KLAKLAK)2, and investigate the synergistic effect of Gamma-irradiation and KLA for tumor cells inhibition in vitro. MATERIAL AND METHODS: In this experimental study, KLA was delivered into THP-1 cells using a Cell-Penetrating Peptide (CPP).The cells were then exposed to gamma-ray radiation both in the presence and absence of KLA conjugated with CPP. The impacts of KLA, ionizing radiation or combination of both were then evaluated on the cell proliferation and apoptosis of THP-1 cells using MTT assay and flow cytometry, respectively. RESULTS: The MTT assay indicated the anti-proliferative effects of combined D (KLAKLAK)2 peptide with ionizing radiation on THP-1cells. Moreover, synergetic effects of KLA and ionizing radiation reduced cell viability and consequently enhanced cell apoptosis. CONCLUSION: Using KLA peptide in combination with ionizing irradiation increases the anticancer effects of radio-resistant THP-1 cells. Therefore, the combinational therapy of (KLAKLAK)2 and radiation is a promising strategy for cancer treatment the in future.

20.
Chemosphere ; 281: 130795, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34022601

RESUMEN

In the present study, gold nanoparticles were locally well-decorated on the surface of TiO2 using the tungstophosphoric acid (HPW), as UV-switchable reducing intermediate linkers. The prepared Au NPs/HPW/TiO2 nanostructure was characterized using FTIR, XRD, EDS, SEM and TEM, which confirmed the successful attachment of quasi-spherical Au NPs in the range of 20-30 nm on the surface of HPW modified TiO2. Also, the FTIR results show that the Au NPs were binded to TiO2 through the terminal the oxygen atoms HPW. The photocatalytic performance of prepared nanostructures was assessed in degradation of nitrobenzene. The nitrobenzene photodegradation kinetic study revealed that it well followed the Langmuir-Hinshelwood kinetic model with the apparent rate constant of 0.001 min-1 using anatase TiO2, 0.0004 min-1 using HPW, 0.0014 using HPW/TiO2, while it was obtained 0.0065 min-1 using Au NPs@HPW/TiO2 nanostructure. It shows that the photocatalytic rate of the prepared nanocomposites increased by 6.5- and 4.6-fold compared to photoactivity of anatase TiO2 and HPW/TiO2 respectively. Also, the photocatalytic mechanism of process was proposed. Moreover, the reusability study confirmed that its photocatalytic activity still remained high after three cycles.


Asunto(s)
Oro , Nanopartículas del Metal , Catálisis , Titanio
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