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1.
Biol Trace Elem Res ; 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080233

RESUMEN

The role of heavy metals on human health has often been discussed regarding disease pathogenesis and risk factors. Alzheimer's disease (AD), a prevalent neurodegenerative disease, is no exception. We conducted a comprehensive examination to assess the concentrations of lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) in biological samples of AD patients in comparison with a group of individuals without AD, with the objective of our study being to perform a systematic review on this topic. We performed this systematic review by searching various databases/search engines, including Web of Science, Scopus, PubMed, and Google Scholar, until December 7, 2022. Relevant studies were scrutinized for eligibility. Meta-analysis was performed on studies with sufficient data using STATA software. Twenty-seven out of 3349 studies met pre-defined eligibility criteria and were included in our systematic review. For the meta-analysis, 22 studies with 3346 participants (1291 AD patients and 2055 healthy controls) had sufficient data for inclusion in the analysis. Using a random-effects model, we found that pooled data indicated patients with AD had significantly higher levels of Cd in their biological samples compared to controls (Hedges' g, 0.83; 95% CI, 0.11, 1.54; p = 0.023). However, other heavy metals were not significantly different in circulatory samples of AD patients compared to healthy controls (p > 0.05). This systematic review and meta-analysis indicated that Cd concentrations in AD patients were significantly higher than in healthy controls. Other included heavy metals may not be directly associated with increased risk of AD.

2.
Curr Med Chem ; 31(11): 1348-1360, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-36892027

RESUMEN

Statins (3-hydroxy-3-methylglutaryl-CoA reductase inhibitors) reduce plasma cholesterol and improve endothelium-dependent vasodilation, inflammation, and oxidative stress. The effect of statins on the central nervous system (CNS), particularly on cognition and neurological disorders such as cerebral ischemic stroke, multiple sclerosis (MS), and Alzheimer's disease (AD), has received increasing attention in recent years, both within the scientific community and in the media. This review aims to provide an updated discussion on the effects of statins on the differentiation and function of various nervous system cells, including neurons and glial cells. Additionally, the mechanisms of action and how different types of statins enter the CNS will be discussed.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas , Esclerosis Múltiple , Enfermedades del Sistema Nervioso , Accidente Cerebrovascular , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Sistema Nervioso Central
3.
MedComm (2020) ; 4(6): e386, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37873514

RESUMEN

Contact dermatitis (CD) is an inflammatory skin disease of eczema that is elicited by chemicals or metal ions that have toxic effects without eliciting a T-cell response (contact elicitation) or by small reactive chemicals that modify proteins and induce innate and adaptive immune responses (contact allergens). The clinical condition is characterized by localized skin rash, pruritus, redness, swelling, and lesions, which are mainly detected by patch tests and lymphocyte stimulation. Heavy metals such as palladium (Pd), platinum (Pt), and titanium (Ti) are ubiquitous in our environment. These heavy metals have shown CD effects as allergic agents. Immunological responses result from the interaction of cytokines and T cells. Occupational metal CD accounts for most cases of work-related cutaneous disorders. In this systematic review, the allergic effects of heavy metals, including Pd, Pt, and Ti, and the mechanisms, clinical manifestations, prevalence, and therapeutic approaches are discussed in detail. Furthermore, the therapeutic approaches introduced to treat CD, including corticosteroids, topical calcineurin inhibitors, systemic immunosuppressive agents, phototherapy, and antihistamines, can be effective in the treatment of these diseases in the future. Ultimately, the insights identified could lead to improved therapeutic and diagnostic pathways.

4.
Am J Clin Exp Immunol ; 12(3): 24-44, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37457503

RESUMEN

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes Coronavirus Disease 2019 (COVID-19), one of the deadliest medical difficulties to affect people in more than a century. The virus has now spread to many countries worldwide, posing a big challenge to the health status of people in affected populations. Gaining more knowledge about the different aspects of this virus will lead us to better control and treatment methods. In this paper, we discuss the SARS-CoV-2 structure and the mechanism of this virus's entry into host cells through angiotensin-converting enzyme 2 (ACE2), the main receptor for the SARS-CoV-2 virus. The main connection between SARS-CoV-2 and ACE2 is Spike protein. Other topics are also included, like ACE2 structure, functions, and physiology. For instance, ACE2 is involved in the renin-angiotensin-aldosterone system, Angiotensin A/ACE2/Alamandine/MAS-Related GPCR D (MrgD) Axis, the Kinin-Kallikrein System. It also acts as Chaperone Protein for the Amino Acid Transporter, B0AT1, and has a connection with Apelin Peptides. Since ACE2 plays a primary role in COVID-19 pathogenesis, scientists have discovered some SARS-CoV-2 therapy methods based on ACE2 targeting. Tissue expression in different genders and ages, polymorphisms, and host epigenetics, the role of ACE2 in hypertension, and cytokine storm are explained separately.

5.
J Trace Elem Med Biol ; 79: 127240, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37331278

RESUMEN

Contact dermatitis is an inflammatory skin reaction caused by direct contact with chemical substances in the environment and can either be irritant or allergic in nature. The clinical symptoms of contact dermatitis, include local skin rash, itching, redness, swelling, and lesions. Nowadays, 15-20% of people have some degree of contact dermatitis, which can be more or less severe. Immune responses in allergic contact dermatitis (ACD) are due to the effects of cytokines and allergen-specific CD4+ and CD8+ T cells on the skin. Acids and alkalis such as drain cleaners, plants such as poinsettias, hair colors, and nail polish remover, are all prominent causes of irritant contact dermatitis (ICDs). Heavy metals are metallic elements with a high atomic weight that are hazardous in low quantities and are known to cause dermatitis after systemic or local exposure. Nickel (Ni), chromium (Cr), lead (Pb), and copper (Cu) are among the most common heavy metals used in various industries. Metal allergies may cause ACD and also systemic contact dermatitis (SCD). Contact dermatitis is detected by laboratory tests such as patch testing, lymphocyte stimulation test (LST), and evaluation of cytokine production by primary cultures of peripheral blood mononuclear cells. This article presents an update on the epidemiological and clinical characteristics of ACD and SCD caused by three heavy metals (Cr, Cu, and Pb). Ni is not discussed due to recent coverage. Furthermore, the effects of contact sensitivity to some other heavy metals, such as gold (Au), cobalt (Co), palladium (Pd), and mercury (Hg) are discussed.


Asunto(s)
Dermatitis Alérgica por Contacto , Mercurio , Metales Pesados , Humanos , Irritantes , Linfocitos T CD8-positivos , Plomo , Leucocitos Mononucleares , Metales Pesados/toxicidad , Dermatitis Alérgica por Contacto/etiología , Dermatitis Alérgica por Contacto/diagnóstico , Níquel , Cromo , Mercurio/toxicidad
6.
J Interferon Cytokine Res ; 43(4): 147-163, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37062817

RESUMEN

Cytokine storm refers to the overproduction of immune and inflammatory cells and their proteins (cytokines) [interleukin (IL)-1 and IL-6] causing acute respiratory distress syndrome in COVID-19. COVID-19 causes inflammatory reactions, and patients with COVID-19 had categorized as mild, severe, and critical after reviewing previous studies. Then, it is crucial to find immune-inflammatory indicators that might predict the disorder severity and the prognosis primarily for guiding medical therapy in the face of this unexpectedly developing unique infectious disease. Higher levels of IL-6 and IL-1 levels might be seen in patients with COVID-19 at each stage. In addition, IL-1-induced IL-6 assists in the synthesis of liver C-reactive protein (CRP) in acute phase responses. Recent studies suggested that IL-6 levels are an independent predictor of COVID-19 illness because they were significantly higher in patients with severe than with mild COVID-19 symptoms. Anakinra and tocilizumab (TCZ) are beneficial in lowing mortality in COVID-19 patients; however, information on their safety and efficacy is scarce. The aim of this study was to investigate the role of inflammatory cytokines (IL-1 and IL-6) as potential biomarkers in the different stages (mild, severe, and critical) of COVID-19. A systematic search during the years 2021-2022 using the keywords SARS-CoV-2, COVID-19, IL-6, IL-1, CRP, mild stage, severe stage, critical stage, cytokine storm, tocilizumab, and anakinra was performed in PubMed and Google Scholar databases. This study reviews studies that have investigated the role of high levels of these cytokines in the severity of the disease in patients with COVID-19 and the inhibitory function of TCZ and anakinra in preventing mechanical ventilation and patient mortality. According to the result, studies suggest that decreased innate immune response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in association with the production of inflammatory cytokines is the determining and driving function of COVID-19.


Asunto(s)
COVID-19 , Humanos , Interleucina-6 , Citocinas , SARS-CoV-2 , Interleucina-1 , Proteína Antagonista del Receptor de Interleucina 1/uso terapéutico , Síndrome de Liberación de Citoquinas , Biomarcadores , Proteína C-Reactiva
7.
Phytother Res ; 37(3): 1003-1014, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36744753

RESUMEN

The immune network is an effective network of cell types and chemical compounds established to maintain the body's homeostasis from foreign threats and to prevent the risk of a wide range of diseases; hence, its proper functioning and balance are essential. A dysfunctional immune system can contribute to various disorders, including cancer. Therefore, there has been considerable interest in molecules that can modulate the immune network. Curcumin, the active ingredient of turmeric, is one of these herbal remedies with many beneficial effects, including modulation of immunity. Curcumin is beneficial in managing various chronic inflammatory conditions, improving brain function, lowering cardiovascular disease risk, prevention and management of dementia, and prevention of aging. Several clinical studies have supported this evidence, suggesting curcumin to have an immunomodulatory and anti-inflammatory function; nevertheless, its mechanism of action is still not clear. In the current review, we aim to explore the modulatory function of curcumin through interferons in cancers.


Asunto(s)
Curcumina , Neoplasias , Humanos , Curcumina/farmacología , Interferones , Neoplasias/tratamiento farmacológico , Antiinflamatorios , Sistema Inmunológico , Curcuma/química
8.
Rev Environ Health ; 38(3): 577-587, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-35735094

RESUMEN

OBJECTIVES: Humic acid (HA) compounds in the disinfection processes of drinking water and wastewater are considered as precursors of highly toxic, carcinogenic and mutagenic disinfectant by-products. The aim of this study was to systematically review all research studies on the photocatalytic degradation of humic acid and to evaluate the laboratory conditions and results of these studies. CONTENT: The present systematic review was performed by searching the Scopus, PubMed, and web of science databases until December 2021. The parameters of type of catalyst, catalyst size, optimum pH, optimum initial concentration of humic Acid, optimum catalyst concentration, optimum time, light used and removal efficiency were investigated. SUMMARY: 395 studies were screened and using the inclusion and exclusion criteria, in total, 20 studies met our inclusion criteria and provided the information necessary to Photocatalytic degradation of humic acid by nanoparticles. In the investigated studies, the percentage of photocatalytic degradation of humic acid by nanoparticles was reported to be above 70%, and in some studies, the removal efficiency had reached 100%. OUTLOOK: From the results of this systematic review, it was concluded that the photocatalytic process using nanoparticles has a high effect on the degradation of humic acid.


Asunto(s)
Agua Potable , Nanopartículas , Sustancias Húmicas , Titanio , Aguas Residuales
9.
Environ Sci Pollut Res Int ; 30(2): 3862-3871, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35960468

RESUMEN

The presence of humic acid compounds in water resources, as one of the precursors of Trihalomethanes and Holoacetic acids, causes health problems for many communities. The aim of this research study was to investigate the photocatalytic degradation efficiency of humic acid using MnFe2O4@TiO2 nanoparticles which produced by green synthesis method. The synthesis of metal nanoparticles using plant extracts and the study of their catalytic performance is a relatively new topic. Many chemical techniques have been proposed for the synthesis of MnFe2O4@TiO2 nanoparticles, but green synthesis has received much attention due to its availability, simplicity, and non-toxicity. The properties of synthesized nanoparticles were determined by SEM, FT-IR, XRD, EDS, and DLS analysis. The results of the study showed that under optimal experimental conditions (pH = 3, nanocomposite dose = 0.03 g/L, humic acid initial concentration = 2 mg/L, and contact time = 20 min), it is possible to achieve maximum degradation of humic acid. Therefore; MnFe2O4@TiO2 nanoparticles have high efficiency for removing of humic acid from aqueous solutions under UV light.


Asunto(s)
Nanopartículas del Metal , Nanocompuestos , Sustancias Húmicas/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Corteza de la Planta/química , Agua , Titanio/química , Nanopartículas del Metal/química , Rayos Ultravioleta , Nanocompuestos/química , Catálisis
10.
Int J Low Extrem Wounds ; : 15347346221118497, 2022 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-35950795

RESUMEN

In recent years, nanotechnology and the subsequent production of nanoparticles have developed excellent methods for medical applications, including wound healing. One of these nanoparticles is bentonite nanoparticles (BNPs) which show high ability in tissue engineering. But our knowledge of its effectiveness in wound healing is based on little data. Therefore, the main purpose of this study was to evaluate the wound healing ability of BNPs and in the next step the suitability of honey as a solvent for these nanoparticles. Methods: In this experimental study, an excisional wound injury model was developed in adult male BALB/c mice (n = 60) by creative two equal-sized wounds (5 mm) on either side of their back midline. The animals were allocated into five groups (n = 12 each) as untreated control (U), honey (H), polyethylene glycol (P), and (BNPs) dissolved in honey or polyethylene glycol (H + BNPs, P + BNPs). Animals have received their relative topical treatments twice per day for 14 consecutive days. Tissue sampling was carried out on days 4, 7, 10, and 14. The tissue sections were stained with hematoxylin and eosin and Trichrome-Masson staining methods. The histomorphological parameters including inflammatory cells infiltration, fibroblasts, re-epithelialization, granulation formation, and collagenases were evaluated in all tissue sections. Data were analyzed by SPSS 16 software. Comparison between the groups was performed by one-way analysis of variance following Tukey's post-hoc test. Compared to the control group, BNPs showed significant wound healing activities with lower inflammatory cells infiltration, higher fibroblastosis and new epithelium thickness, and greater granulation area and collagen fibers density in the ulcer bed. In addition, honey as a solvent synergistically increased the wound healing activity of the studied nanoparticle. These results for the first time are clearly showing that BNPs have a promising wound healing activity, especially when applied with honey concurrently.

11.
Environ Sci Pollut Res Int ; 29(24): 35682-35706, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35257333

RESUMEN

We performed a systematic and meta-analysis study to find the association between cadmium (Cd) exposure and blood pressure (BP)/hypertension (HTN) in exposed general populations. We searched main databases for literature published between year 2000 and April 15, 2021. Quality assessment was performed with the Joanna Briggs Institute (JBI) critical appraisal tools. Heterogeneity between studies was determined by I-squared (I2) statistic. The random effects model was used to determine the association between blood and urine Cd levels with hypertension. The overall standard differences in mean for Cd level in hypertensive and control groups were 3.34, 1.79, and 8.09 based on samples from blood, urine, and hair, respectively. The overall standard differences in mean for Cd level in the low and high exposure groups were - 0.795 and - 1.036 based on blood and urinary samples, respectively. Our findings indicate a positive relationship between blood and hair Cd levels and hypertension. We also found that hair is the optimal biological sample to find the relationship between Cd exposure and hypertension for both genders. However, more studies are needed to confirm these findings.


Asunto(s)
Cadmio , Hipertensión , Presión Sanguínea , Cadmio/análisis , Exposición a Riesgos Ambientales/análisis , Femenino , Humanos , Hipertensión/epidemiología , Masculino
12.
Phytother Res ; 36(4): 1616-1632, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35302258

RESUMEN

Systemic autoimmune diseases like rheumatoid arthritis, multiple sclerosis, and systemic lupus erythematosus represent various autoimmune conditions identified by immune system dysregulation. The activation of immune cells, auto-antigen outbreak, inflammation, and multi-organ impairment is observed in these disorders. The immune system is an essential complex network of cells and chemical mediators which defends the organism's integrity against foreign microorganisms, and its precise operation and stability are compulsory to avoid a wide range of medical complications. Curcumin is a phenolic ingredient extracted from turmeric and belongs to the Zingiberaceae, or ginger family. Curcumin has multiple functions, such as inhibiting inflammation, oxidative stress, tumor cell proliferation, cell death, and infection. Nevertheless, the immunomodulatory influence of curcumin on immunological reactions/processes remains mostly unknown. In the present narrative review, we sought to provide current information concerning the preclinical and clinical uses of curcumin in systemic autoimmune diseases.


Asunto(s)
Artritis Reumatoide , Enfermedades Autoinmunes , Curcumina , Lupus Eritematoso Sistémico , Artritis Reumatoide/metabolismo , Enfermedades Autoinmunes/tratamiento farmacológico , Curcumina/química , Curcumina/farmacología , Curcumina/uso terapéutico , Humanos , Inflamación/complicaciones , Lupus Eritematoso Sistémico/tratamiento farmacológico
13.
Int J Low Extrem Wounds ; : 15347346221074583, 2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35188413

RESUMEN

Background and aim: Up to now, proper wound care management has remained as an important clinical challenge. Chitosan nanosheets (CNSs) showed a great potential in tissue engineering, but our knowledge about their wound healing effectiveness is based on very limited data. Thus, the aim of this research was to evaluate the wound healing potential of CNSs and honey as a vehicle for these nanoparticles. Methods: The skin excisional wound injury model was made in adult male BALB/c mice (n = 60) by creating two identical sized wounds (5mm) on either side of their dorsal midline. The animals were divided into five groups (n = 12 each) as untreated control, honey, polyethylene glycol, and CNSs dissolved either in honey or polyethylene glycol. Animals were received their relative topical treatments twice per day for 14 consecutive days. Tissue sampling was carried out on days 4, 7, 10, and 14 post wounding. The histological parameters including inflammatory cells infiltration, fibroblast proliferation, re-epithelialization, granulation formation, and collagen formation were evaluated in all studied time points. Results: Compared to the control group, CNSs showed significant wound healing activities with lower inflammatory cells infiltration, higher fibroblastosis and new epithelium thickness, and greater granulation area and collagen fibers density in the ulcer bed. In addition, honey synergistically increased the wound healing activity of the studied nanoparticles. Conclusion: These results showed that CNSs have promising wound healing activity specially when dissolved with honey concurrently.

14.
Rev Environ Health ; 37(2): 281-289, 2022 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-34090316

RESUMEN

OBJECTIVES: This study was performed to review epidemiological evidence related to Arsenic (As) effects on the thyroid function by focusing on the serum thyroid hormone concentration. CONTENT: As, one of the main pollutants, has been recognized as an endocrine-disrupting agent that may affect the function of thyroid as shown by experimental studies. SUMMARY: This systematic study indicates the association between As exposure and thyroid dysfunction. The studies have shown an association between serum and urine concentration of arsenic and thyroid dysfunction. Most of them reported the association between increase in the serum or urine As levels and decrease in the triiodothyronine (T3) and thyroxine (T4), and also elevation in the thyrotropic hormone (TSH) levels. OUTLOOK: Our findings related to the effects of As on the function of thyroid in humans are still limited and future studies should be done to address this question.


Asunto(s)
Arsénico , Glándula Tiroides , Arsénico/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Humanos , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/fisiopatología , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangre
15.
Nanomaterials (Basel) ; 11(12)2021 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-34947559

RESUMEN

Thermal energy storage is an important component in energy units to decrease the gap between energy supply and demand. Free convection and the locations of the tubes carrying the heat-transfer fluid (HTF) have a significant influence on both the energy discharging potential and the buoyancy effect during the solidification mode. In the present study, the impact of the tube position was examined during the discharging process. Liquid-fraction evolution and energy removal rate with thermo-fluid contour profiles were used to examine the performance of the unit. Heat exchanger tubes are proposed with different numbers and positions in the unit for various cases including uniform and non-uniform tubes distribution. The results show that moving the HTF tubes to medium positions along the vertical direction is relatively better for enhancing the solidification of PCM with multiple HTF tubes. Repositioning of the HTF tubes on the left side of the unit can slightly improve the heat removal rate by about 0.2 in the case of p5-u-1 and decreases by 1.6% in the case of p5-u-2. It was found also that increasing the distance between the tubes in the vertical direction has a detrimental effect on the PCM solidification mode. Replacing the HTF tubes on the left side of the unit negatively reduces the heat removal rate by about 1.2 and 4.4%, respectively. Further, decreasing the HTF temperature from 15 °C to 10 and 5 °C can increase the heat removal rate by around 7 and 16%, respectively. This paper indicates that the specific concern to the HTF tube arrangement should be made to improve the discharging process attending free convection impact in phase change heat storage.

16.
Materials (Basel) ; 14(5)2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33807894

RESUMEN

Utilizing phase change materials in thermal energy storage systems is commonly considered as an alternative solution for the effective use of energy. This study presents numerical simulations of the charging process for a multitube latent heat thermal energy storage system. A thermal energy storage model, consisting of five tubes of heat transfer fluids, was investigated using Rubitherm phase change material (RT35) as the. The locations of the tubes were optimized by applying the Taguchi method. The thermal behavior of the unit was evaluated by considering the liquid fraction graphs, streamlines, and isotherm contours. The numerical model was first verified compared with existed experimental data from the literature. The outcomes revealed that based on the Taguchi method, the first row of the heat transfer fluid tubes should be located at the lowest possible area while the other tubes should be spread consistently in the enclosure. The charging rate changed by 76% when varying the locations of the tubes in the enclosure to the optimum point. The development of streamlines and free-convection flow circulation was found to impact the system design significantly. The Taguchi method could efficiently assign the optimum design of the system with few simulations. Accordingly, this approach gives the impression of the future design of energy storage systems.

17.
Rev Environ Health ; 36(3): 359-366, 2021 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-33128529

RESUMEN

Heavy metals in drinking water can threat human health and may induce several diseases. The association between heavy metals exposure and chronic kidney disease (CKD) has been indicated by few epidemiological studies. We conducted a systematic review of the epidemiologic publications of the association between exposure to heavy metals through drinking water and CKD. Keywords related to heavy metals and kidney diseases on MeSH were identified and searched in PubMed, Google Scholar, Scopus, Ovid-Medline and Web of Science until July 2020. 14 publications met our inclusion criteria and included in the current review. The included articles were conducted on the association between arsenic, cadmium, lead and chromium in drinking water and CKD. Our study could not find strong evidence between heavy exposure to through drinking water and CKD, except for arsenic. The negative association was found between arsenic and lead and glomerular filtration rate (eGFR). The positive correlation was observed between cadmium exposure and urinary N-acetyl-ß-d-glucosaminidase (NAG) concentrations, and also arsenic and chromium exposure and kidney injury molecule (KIM-1). Assessment of studies showed an association between arsenic, cadmium, lead and chromium and albuminuria and proteinuria, without CKD outcomes. Current systematic study showed few evidence for exposure to arsenic, cadmium, lead and chromium through drinking water and incidence of kidney problems. However, more epidemiological studies are required to confirm this association.


Asunto(s)
Arsénico , Agua Potable , Metales Pesados , Insuficiencia Renal Crónica/epidemiología , Contaminantes Químicos del Agua , Biomarcadores , Humanos , Riñón/fisiopatología , Insuficiencia Renal Crónica/fisiopatología
18.
Water Sci Technol ; 82(11): 2250-2258, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33339781

RESUMEN

The purpose of this study was to examine the nitrate adsorption by cobalt ferrite (CFO) nanoparticles. The adsorbent was synthesized by co-precipitation method and its structure was characterized using scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and vibrating-sample magnetometry. In batch adsorption studies, the effects of various parameters like pH (3-11), adsorbent dose (0.2-0.8 g/L), contact time (5-120 min), initial nitrate concentration (50-200 mg/L), and temperature (283-313 K) on the adsorption process were examined. The results of this study indicated that the maximum adsorption capacity was 107.8 mg/g (optimum condition pH = 3, adsorbent dosage: 0.2 g/L, nitrate concentration: 200 mg/L, contact time: 20 min and temperature: 313 K). The adsorption isotherm had a proper match with Langmuir (R2 = 0.99) and Freundlich (R2 = 0.99) models. The adsorption of nitrate by CFO followed pseudo-second-order kinetics. The results of the thermodynamics of the nitrate adsorption process by CFO showed that all the values of Gibbs free energy change, enthalpy change and entropy change were positive. Therefore, this process was endothermic and non-spontaneous.


Asunto(s)
Nanopartículas , Contaminantes Químicos del Agua , Adsorción , Cobalto , Compuestos Férricos , Concentración de Iones de Hidrógeno , Cinética , Nitratos , Soluciones , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termodinámica
19.
Bioorg Chem ; 103: 104194, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32890997

RESUMEN

In this study, CoFe2O4@ZnO-CeO2 magnetic nanocomposite (CoFe@Zn-Ce MNC) was successfully prepared by facile sonochemical method for the first time. CoFe@Zn-Ce MNC was obtained by green and cost-effective process in the presence of Crataegus microphylla (C. microphylla) fruit extract. Influence of some parameters like capping agents (C. microphylla, SDS and CTAB), sonication time (10, 30 and 60 min) and sonication power (40, 60 and 80 W) were studied to achieve optimum condition. The as-obtained products were characterized by FT-IR, FESEM, TEM, DRS, VSM, EDS, TGA and XRD analysis. Results showed that high magnetic properties (20.38 emug-1), 70-80 nm size and spherical morphology were unique characteristics of synthesized nanocomposite. Antibacterial activity of CoFe@Zn-Ce MNC was examined against E. coli, P. aeruginoss and S. aureus bacteria. Among theme, S. aureus as gram-positive bacteria showed excellent antibacterial activity. Furthermore, photocatalytic performance of the CoFe@Zn-Ce MNC was investigated by degradation of humic acid (HA) molecules under visible and UV light irradiations. The influence of morphology of products and incorporation of cerium oxide with CoFe2O4@ZnO on photocatalytic activity of CoFe2O4@ZnO was performed. After 100 min illumination, the decomposition of HA pollutant by magnetic nanocomposite were 97.2% and 72.4% under exposure of UV and visible light irradiations, respectively. Also, CoFe@Zn-Ce MNC demonstrated high stability in the cycling decomposition experiment after six times cycling runs.


Asunto(s)
Antibacterianos/farmacología , Crataegus/química , Nanocompuestos/química , Extractos Vegetales/química , Antibacterianos/síntesis química , Antibacterianos/efectos de la radiación , Catálisis/efectos de la radiación , Cerio/química , Cerio/efectos de la radiación , Cobalto/química , Cobalto/efectos de la radiación , Compuestos Férricos/química , Compuestos Férricos/efectos de la radiación , Tecnología Química Verde/métodos , Sustancias Húmicas , Fenómenos Magnéticos , Nanopartículas del Metal/química , Nanopartículas del Metal/efectos de la radiación , Pruebas de Sensibilidad Microbiana , Nanocompuestos/efectos de la radiación , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Ondas Ultrasónicas , Rayos Ultravioleta , Óxido de Zinc/química , Óxido de Zinc/efectos de la radiación
20.
J Photochem Photobiol B ; 209: 111949, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32659646

RESUMEN

Scientists are interested in biosynthesis of gold nanoparticles owing to their catalytic and biological features. In this research, the extract of Convolvulus fruticosus (C. fruticosus; CFE) extract was applied to synthesize spherical-like gold nanoparticles (CFE@AuNPs). As-prepared CFE@AuNPs was characterized by TEM, FE-SEM, XRD, FT-IR, EDS, UV-Vis and DLS analysis. Identification analysis revealed that the properties of as-prepared CFE@AuNPs with spherical morphology were homogeneous, regular, high dispersibility and low agglomeration. The particle size of biogenic gold nanoparticles (about 35 nm) was obtained using FE-SEM, TEM and DLS techniques. Photocatalytic experiment of CFE@AuNPs determined by degradation of basic violet 10 (BV10), basic blue 9 (BB9) and acid red 51 (AR51) pollutants with percent degradation of 94.3%, 90.2%, 85.4% under UV and 80.6%, 79.8%, 73.3% under visible light irradiation, respectively. As well as, as-prepared CFE@AuNPs illustrated as a significant inhibitory influence against ATCC strain for both gram-positive and gram-negative bacteria. Owing to the antibacterial results, CFE@AuNPs enhanced antibacterial activity against E. coli, A. baumannii, P. aeruginosa, S. aureus, K. pneumonia, P. mirabilis and E. faecalis with MIC of 0.075, 0.075, 0.075, 0.075, 0.15, 0.075 and 0.037 mg/ml, respectively. All in all, results of the findings showed that C. fruticosus capped gold nanoparticles can find applications in the various arena including biological and removal of toxic pollutants for water purification.


Asunto(s)
Antibacterianos/farmacología , Convolvulus/química , Oro/química , Nanopartículas del Metal/química , Extractos Vegetales/farmacología , Catálisis , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Análisis Espectral/métodos , Temperatura , Difracción de Rayos X
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