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1.
Chemosphere ; 353: 141547, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38447896

RESUMEN

Today, the main goal of many researchers is the use of high-performance, economically and industrially justified materials, as well as recyclable materials in removing organic and dangerous pollutants. For this purpose, sol-gel derived carbon aerogel modified with nickel (SGCAN) was used to remove Cefixime from aqueous solutions. The influence of important parameters in the cefixime adsorption onto SGCAN was modeled and optimized using artificial neural network (ANN), response surface methodology (RSM), genetic algorithm (GA), and SOLVER methods. R software was applied for this purpose. The design range of the runs for a time was in the range of 5 min-70 min, concentration in the range of 5 mg L-1 to 40 mg L-1, amount of adsorbent in the range of 0.05 g L-1 to 0.15 g L-1, and pH in the range of 2.0-11. The results showed that the ANN model due to lower Mean Squared Error (MSE), Sum of Squared Errors (SSE), and Root Mean Squared Error (RMSE) values and also higher R2 is a superior model than RSM. Also, due to the superiority of ANN over the RSM model, the optimum results were calculated based on GA. Based on GA, the highest Cefixime adsorption onto SGCAN was obtained in pH, 5.98; reaction time, 58.15 min; initial Cefixime concentration, 15.26 mg L-1; and adsorbent dosage, 0.11 g L-1. The maximum adsorption capacity of Cefixime onto SGCAN was determined to be 52 mg g-1. It was found the pseudo-second-order model has a better fit with the presented data.


Asunto(s)
Carbono , Contaminantes Químicos del Agua , Níquel , Cefixima , Adsorción , Redes Neurales de la Computación , Concentración de Iones de Hidrógeno , Cinética
2.
Toxicology ; 500: 153660, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37924934

RESUMEN

One of the most frequent environmental contaminants, benzene is still widely used as an industrial solvent around the world, especially in developing nations, posing a serious occupational risk. While the processes behind the toxicity of benzene grounds are not fully understood, it is generally accepted that its metabolism, which involves one or more reactive metabolites, is crucial to its toxicity. In order to evaluate the many ways that benzene could influence gene regulation and thus have an impact on human health, new methodologies have been created. The pathophysiology of the disorder may result from epigenetic reprogramming caused by exposure to benzene, including changes in non-coding RNA (ncRNA) markers, according to recent studies. We are interested in the identification of hazardous regulatory ncRNAs, the identification of these ncRNAs' targets, and the comprehension of the significance of these interactions in the mechanisms behind benzene toxicity. Hence, the focus of recent research is on long non-coding RNAs (lncRNAs), circular RNAs (circRNAs) and microRNAs (miRNAs), and some of the more pertinent articles are also discussed.


Asunto(s)
MicroARNs , ARN Largo no Codificante , Humanos , Benceno/toxicidad , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , ARN Circular , Regulación de la Expresión Génica
3.
Biomed Pharmacother ; 165: 115054, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37379642

RESUMEN

Ecological air contamination is the non-homogenous suspension of insoluble particles into gas or/and liquid fluids known as particulate matter (PM). It has been discovered that exposure to PM can cause serious cellular defects, followed by tissue damage known as cellular stress. Apoptosis is a homeostatic and regulated phenomenon associated with distinguished physiological actions inclusive of organ and tissue generation, aging, and development. Moreover, it has been proposed that the deregulation of apoptotic performs an active role in the occurrence of many disorders, such as autoimmune disease, neurodegenerative, and malignant, in the human population. Recent studies have shown that PMs mainly modulate multiple signaling pathways involved in apoptosis, including MAPK, PI3K/Akt, JAK/STAT, NFκB, Endoplasmic Stress, and ATM/P53, leading to apoptosis dysregulation and apoptosis-related pathological conditions. Here, the recently published data concerning the effect of PM on the apoptosis of various organs, with a particular focus on the importance of apoptosis as a component in PM-induced toxicity and human disease development, is carefully discussed. Moreover, the review also highlighted the various therapeutic approaches, including small molecules, miRNA replacement therapy, vitamins, and PDRN, for treating diseases caused by PM toxicity. Notably, researchers have considered medicinal herbs a potential treatment for PM-induced toxicity due to their fewer side effects. So, in the final section, we analyzed the performance of some natural products for inhibition and intervention of apoptosis arising from PM-induced toxicity.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Humanos , Material Particulado/efectos adversos , Contaminantes Atmosféricos/toxicidad , Fosfatidilinositol 3-Quinasas/metabolismo , Apoptosis , Transducción de Señal
4.
Int J Biol Macromol ; 235: 123790, 2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-36822288

RESUMEN

Exposure to air pollution has been connected to around seven million early deaths annually and also contributing to higher than 3 % of disability-adjusted lost life years. Particulate matters (PM) are among the key pollutants that directly discharged or formed due to atmospheric chemical interactions. Among these matters, due of its large surface area, PM2.5 may absorb a different harmful and toxic substances. One of the outcomes of such environmental disturbance is oxidative stress which affects cellular processes including apoptosis, inflammation, and epithelial mesenchymal transition. Non-coding RNAs (ncRNA) such as, miRNAs, lncRNAs, and circRNAs are classified as non-protein coding RNA's. Over the past few years these small molecules have been gaining so much attention since they participate in variety of physiological and pathological processes and their expression change during disease periods. Regarding epigenetic properties, ncRNAs play an important function in organism's response to environmental stimulus. In this manner, it was revealed that exposure to PM2.5 may cause epigenetic reprogramming, such as, ncRNAs signature's alteration, which can be effective concerning pathophysiology state. In this review, we describe PM2.5 impact on ncRNAs and excavate its roles in toxicity caused by PM2.5.


Asunto(s)
MicroARNs , ARN Largo no Codificante , Humanos , Material Particulado/toxicidad , ARN no Traducido/genética , MicroARNs/genética , ARN Largo no Codificante/genética , Inflamación
5.
Int J Environ Health Res ; 32(12): 2781-2797, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34696634

RESUMEN

In this study, photocatalytic degradability of Floxin antibiotic by UV/ZnO/sulfite (UZS) advanced oxidation process was evaluated. The degradation rate of Floxin antibiotic by UV/ZnO (UZ) and UV alone processes were 30% and 15%, respectively, within 5 min. It was observed sulfite has a synergistic effect on the performance of UZ, as the complete destruction of Floxin was achieved when sulfite was introduced into the photocatalytic medium. The complete degradation of Floxin by UZS was obtained at pH of 12.0, sulfite/ZnO molar ratio of 1:3 after 5 min of reaction. According to kinetic studies, the observed rate of Floxin degradation (robs (mg L-1 min)) by UZS was 63 and 25 times that of UV alone and UZS, respectively. The values of energy consumption and the total cost for UV alone, UZ and UZS processes were estimated to be (50 kWh m-3 and 1.4 $ m-3), (20 kWh m-3 and 0.98 $ m-3) and (0.78 kWh m-3 and 0.82 $ m-3), respectively.


Asunto(s)
Contaminantes Químicos del Agua , Óxido de Zinc , Cinética , Rayos Ultravioleta , Sulfitos , Antibacterianos
6.
Int J Biol Macromol ; 133: 712-721, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31022483

RESUMEN

Recovery of antibiotics from water and wastewaters has recently gained a great deal of attention due to their serious health and environmental problems. In this work, a magnetite imprinted chitosan polymer nanocomposites (Fe-CS NCs) were synthesized and applied for the adsorptive removal of ciprofloxacin (CIFO) as a model fluoroquinolone antibiotics. The composition and surface morphology of Fe-CS NCs were studied by SEM, BET, XRD, TEM, FTIR and zeta potential meter. Modelling and optimization of adsorption process were studied using response surface methodology (RSM). The reliability of the RSM models was tested by fitting the data. A comparative analysis of the results derived from the models demonstrated that the second-order model was the best. From the contour plotting results, at pH < pHiep low adsorption rate was observed due to protonation of the chitosan NH2 groups, whereas the adsorption rate was significantly enhanced and achieved to a maximum level at pH 6 due to the electrostatic interactions and hydrophobic interactions. Under optimum conditions, maximum removal efficiency and maximum adsorption capacity were obtained 68% and 142 mg/g, respectively. Well regenerability of Fe-CS together with its high capacity of fluoroquinolone antibiotics removal provide a promisable strategy to remediation of wastewaters.


Asunto(s)
Quitosano/química , Ciprofloxacina/química , Óxido Ferrosoférrico/química , Nanocompuestos/química , Adsorción , Cinética , Modelos Químicos , Termodinámica
7.
Carbohydr Polym ; 206: 844-853, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30553392

RESUMEN

Recovery of crystal violet (CV) dye was investigated using magnetic chitosan nano-composites (MCNCs) and the effects of process variables (contact time, initial CV concentration, adsorbent dose, and pH) were optimized through response surface methodology. The reliability of the RSM models (first-order model, first model with interaction, the second-order model, and reduced model) was tested by fitting the data. A comparative analysis of the results derived from the models demonstrated that the reduced model was the best. According to modelling results, MCNCs dosage and contact time were found to be the most effective variables on the adsorption efficiency procedure, respectively. Also, pH had no significant effect on the adsorption uptake statistically. MCNC has the maximum adsorption efficiency (72%) when the contact time, adsorbent dosage, and initial concentration of CV were optimally set as 140 min, 1 g, and 77 mg/L, respectively. Quantity uptake of CV was evaluated using the Langmuir, Freundlich, and Temkin models. Based on findings, Freundlich isotherm fitted well with the experimental results. Kinetic studies showed that the pseudo-first-order model fitted the best the experimental data, which indicated that the adsorption rate of CV molecules onto MCNC was time-dependent. The studies on the well regenerability of MCNC in addition to its high potentiality of cationic dyes removal make it an attractive adsorbent in terms of dye-containing wastewaters treatment.

8.
Food Chem Toxicol ; 113: 278-286, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29407475

RESUMEN

The ingestion of heavy metals through contaminated seafood can causes significant outcomes on human health. In recent years, consume fishes and shrimps has increased in Iran, and several study about heavy metals content in fishes and shrimps from Persian Gulf were carried out to check their food safety. The aims of these systematic reviews and meta-analysis was to summarize the evidence on the relation of the intakes of Arsenic (As) and lead (Pb) levels, based on the origin and sub-groups of shrimp species consumed, Hence that we can estimate the risk of oral cancer induced by Pb and As in these groups of shrimp from the persian gulf. We carried out a search of all suitable studies published between 1995 and 2017 in Scopus, Science Direct, PubMed and Web of Science databases. Since the heterogeneity among studied was significant, we used the random effect model (REM) to perform meta-analysis of data. Data were obtained from 9 articles (14 studies), with 511 samples, and it was reported that pooled levels of As and Pb in the muscle shrimps were 1.37 (95% CI: 0.66-2.08 mg/kg d.w.) and 0.58 (95% CI: 0.33-0.82 mg/kg d.w.), respectively. This pooled levels in muscle shrimps were higher than safe dose reported on Food and Agriculture Organization/World Health Organization guidelines (FAO/WHO). The rank order of shrimps species based on As was Panulirus homarus > Penaeus semisulcatus and for the Pb levels was Litopenaeus vannamei > Panulirus homarus > Fenneropenaeus indicus > Metapenaeus affinis. The lowest and highest risk levels of oral cancer, divided by consumers age groups, were respectively 45-54 (6.94E-04) and 15-24 (8.42E-04) for the Pb, and 45-54 (2.87E-01) and 15-24 (3.51E-01) for arsenic. Incremental Lifetime Cancer Risk (ILCR) of Pb and As was higher than 10-4 and 10-3, respectively. All groups (age) of consumers are subject to the cancer risk of due to the consumption of shrimps contaminated by Pb and As, therefore, should be started a control plan for the reduction of the heavy metal bioaccumulation levels in shrimps of the Persian Gulf coupled to a capillary food safety communication.


Asunto(s)
Arsénico/análisis , Crustáceos/química , Plomo/análisis , Salud Poblacional , Adolescente , Adulto , Animales , Carcinógenos/análisis , Crustáceos/clasificación , Femenino , Humanos , Océano Índico/epidemiología , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/inducido químicamente , Neoplasias de la Boca/epidemiología , Músculos/química , Medición de Riesgo , Alimentos Marinos/análisis , Especificidad de la Especie , Adulto Joven
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