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1.
Public Health ; 221: 66-72, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37421755

RESUMEN

OBJECTIVE: To describe trends in the prevalence of diabetes mellitus (DM) in Brazil and to analyze its association with the consumption of artificially sweetened beverages among individuals aged 18 years or older. STUDY DESIGN: This was a repeated cross-sectional study. METHODS: Annual data from VIGITEL surveys (2006-2020) were used, which included adults from all Brazilian state capitals. The outcome was the prevalence of DM (type 1 and type 2). The main exposure variable was consuming beverages like soft drinks and artificial juices, either in its 'diet, light, or zero' form. Covariates included sex, age, sociodemographic characteristics, smoking, alcohol consumption, physical activity, fruit consumption, and obesity. The temporal trend in the indicators and the etiological fraction (population attributable risk [PAR]) were calculated. Analyses were performed using Poisson regression. The association between DM and consumption of beverages was tested, excluding the year 2020 due to the pandemic; restricting the analysis to the final three years (2018-2020). RESULTS: Overall, 757,386 subjects were included. The prevalence of DM increased from 5.5% to 8.2%, with an annual growth of 0.17 percentage points (95% CI 0.11-0.24). Among those who consumed diet/light/zero beverages, the annual percentage change of DM was four times greater. The PAR corresponding to the consumption of diet/light/zero beverages on the occurrence of DM was 17%. CONCLUSIONS: An increasing prevalence of DM was observed, while diet/light/zero beverages consumption remains stable. A substantial reduction in the annual percentage change of DM could be observed if people stopped consuming diet/light soda/juice.


Asunto(s)
Diabetes Mellitus , Edulcorantes , Adulto , Humanos , Brasil/epidemiología , Bebidas Endulzadas Artificialmente , Estudios Transversales , Bebidas/efectos adversos , Diabetes Mellitus/epidemiología , Diabetes Mellitus/etiología
2.
Int J Dent Hyg ; 13(2): 138-44, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-24995862

RESUMEN

OBJECTIVES: An ex vivo model was designed to profilometrically and histologically assess root changes resulting from scaling with a new ultrasonic device, designed for bone piezoelectric surgery, in comparison with curettes. METHODS: Three groups of 10 periodontal hopeless teeth were each subjected to different root instrumentation: Gracey curettes (CUR); ultrasonic piezoelectric device, Perio 100% setting, level 8 (P100); and ultrasonic piezoelectric device Surg 50% setting, level 1 (S50). After extraction, all teeth were photographed to visually assess the presence of dental calculus. The treated root surfaces were profilometrically evaluated (Ra, Rz, Rmax). Undecalcified histological sections were prepared to assess qualitative changes in cementum thickness. Statistical analysis was carried out using one-way anova test with a significance level of 95%. RESULTS: Both instruments proved to be effective in the complete removal of calculus. The CUR group presented the lowest Ra [2.28 µm (±0.58)] and S50 the highest [3.01 µm (±0.61)]. No statistically significant differences were detected among the three groups, for Ra, Rz and Rmax. Histologically, there was a cementum thickness reduction in all groups, being higher and more irregular in S50 group. CONCLUSIONS: Within the limits of this study, there were no statistically significant differences in roughness parameters analyzed between curettes and the ultrasonic piezoelectric unit. This new instrument removes a smaller amount of cementum, mainly at the Perio 100% power setting, which appears to be the least damaging. The ultrasonic device is effective in calculus removal, proving to be as effective as curettes.


Asunto(s)
Raspado Dental/instrumentación , Ondas de Choque de Alta Energía/uso terapéutico , Aplanamiento de la Raíz/instrumentación , Raíz del Diente/patología , Anciano , Periodontitis Crónica/complicaciones , Cálculos Dentales/patología , Cálculos Dentales/terapia , Cemento Dental/patología , Dentina/patología , Diseño de Equipo , Humanos , Persona de Mediana Edad , Bolsa Periodontal/complicaciones , Fotograbar/métodos , Piezocirugía/instrumentación , Curetaje Subgingival/instrumentación
3.
Environ Technol ; 35(5-8): 611-9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24645440

RESUMEN

This study is a first-hand report of the immobilization of Nauclea diderrichii seed waste biomass (ND) (an agro-waste) with eco-friendly mesoporous silica (MS) and graphene oxide-MS (GO + MS) nanoparticles, producing two new hybrid materials namely: MND adsorbent for agro-waste modified with MS and GND adsorbent for agro-waste modified with GO + MS nanoparticles showed improved surface area, pore size and pore volume over those of the agro-waste. The abstractive potential of the new hybrid materials was explored for uptake of Cr(III) and Pb(II) ions. Analysis of experimental data from these new hybrid materials showed increased initial sorption rate of Cr(III) and Pb(II) ions uptake. The amounts of Cr(III) and Pb(II) ions adsorbed by MND and GND adsorbents were greater than those of ND. Modification of N. diderrichii seed waste significantly improved its rate of adsorption and diffusion coefficient for Cr(III) and Pb(II) more than its adsorption capacity. The rate of adsorption of the heavy metal ions was higher with GO + MS nanoparticles than for other adsorbents. Kinetic data were found to fit well the pseudo-second-order and the diffusion-chemisorption kinetic models suggesting that the adsorption of Cr(III) and Pb(II) onto these adsorbents is mainly through chemisorption mechanism. Analysis of kinetic data with the homogeneous particle diffusion kinetic model suggests that particle diffusion (diffusion of ions through the adsorbent) is the rate-limiting step for the adsorption process.


Asunto(s)
Nanopartículas/química , Eliminación de Residuos/métodos , Rubiaceae/metabolismo , Dióxido de Silicio/química , Purificación del Agua/métodos , Adsorción , Agricultura , Biodegradación Ambiental , Biomasa , Cromo/química , Difusión , Grafito/química , Iones , Cinética , Plomo/química , Espectrometría de Masas , Nanotecnología/métodos , Óxidos/química , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Aguas Residuales , Contaminantes Químicos del Agua/química , Difracción de Rayos X
4.
ACS Omega ; 9(18): 19770-19785, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38737083

RESUMEN

Over the decades, the rise in nitrate levels in the ecosystem has posed a serious threat to the continuous existence of humans, fauna, and flora. The deleterious effects of increasing levels of nitrates in the ecosystem have led to adverse health and environmental implications in the form of methemoglobinemia and eutrophication, respectively. Different pathways/routes for the syntheses of perovskites and their oxides were presented in this review. In recent times, electrocatalytic reduction has emerged as the most utilized technique for the conversion of nitrates into ammonia, an industrial feedstock. According to published papers, the efficiency of various perovskites and their oxides used for the electrocatalytic reduction of nitrate achieved a high Faradaic efficiency of 98%. Furthermore, studies published have shown that there is a need to improve the chemical stability of perovskites and their oxides during scale-up applications, as well as their scalability for industrial applications.

5.
Environ Sci Process Impacts ; 26(3): 595-610, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38323594

RESUMEN

The presence of antimicrobials in water has grown into a major global health concern. This study thus focused on the presence, ecological implications, and potential health risks associated with nine antimicrobials: five antibiotics (ampicillin, chloramphenicol, ciprofloxacin, metronidazole, and tetracycline) and four parabens (methylparaben, ethylparaben, propylparaben, and butylparaben) in surface water and groundwater samples collected from three Southwestern States in Nigeria (Osun, Oyo, and Lagos States). These antimicrobials were widely detected across the three States with ciprofloxacin being the most dominant having maximum average concentrations of 189 µg L-1 and 319 µg L-1 in surface water and groundwater respectively. The range of average concentrations of antibiotics in surface water are 47.3-235 µg L-1 (Osun), 27.9-166 µg L-1 (Oyo) and 52.1-159 µg L-1 (Lagos). For groundwater, it is 35.3-180 µg L-1 (Osun), 26.5-181 µg L-1 (Oyo) and 32.3-319 µg L-1 (Lagos). The average concentrations of all parabens were 32.4-153 µg L-1, 53.4-80.1 µg L-1, and 83.2-132 µg L-1 for surface water and 46.7-55.7 µg L-1, 53-117 µg L-1, and 62.4-118 µg L-1 for groundwater in Osun, Oyo, and Lagos States respectively. Methylparaben was most frequently detected paraben with average concentrations of 153 µg L-1 and 117 µg L-1 in surface water and groundwater respectively. The measured environmental concentrations of these antimicrobials pose a significant ecological risk while those of ciprofloxacin and ampicillin pose a high health risk to all population groups studied. The average concentrations of antibiotics investigated in this study exceeded their threshold values for Predicted No-Effect Concentrations (PNEC) associated with resistance selection, except for tetracycline.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Parabenos/análisis , Agua , Nigeria , Medición de Riesgo , Antibacterianos/análisis , Tetraciclina , Ciprofloxacina , Ampicilina , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente
6.
RSC Adv ; 14(2): 982-994, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38174237

RESUMEN

This study provides, for the first time, data on the distribution and toxicity of catechol (CAT) and hydroquinone (HQ) in drinking water sources from Africa. Groundwater (boreholes and hand-dug wells) and surface water in three Southwestern States in Nigeria served as sampling sites. The concentrations of CAT and HQ in groundwater and surface water were determined throughout a period of 12 months, evaluating the effects of seasonal variation (rainy and dry seasons). Mean concentrations of CAT in water samples were higher than those of HQ. In this study, CAT was more frequently detected, with its mean concentration in groundwater samples higher in the rainy season (430 µg L-1) than in the dry season (175 µg L-1). Multivariate analysis using the Principal Component Analysis Software suggests that in most sample sites, CAT and HQ in water samples were from entirely different anthropogenic sources. The most impacted population groups were the toddlers and infants. Similarly, maximum and median concentrations of CAT in water samples pose serious risks to Daphnia at both acute and chronic levels. The results from this study suggest the need for further control of these dihydroxybenzenes through regular monitoring and removal from drinking water during treatment.

7.
Matern Child Health J ; 17(2): 319-29, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22411705

RESUMEN

A significant reduction in maternal mortality was witnessed globally in the year 2010, yet, no significant reduction in the maternal mortality ratio (MMR) in Nigeria was recorded. The absence of accurate data on the numbers, causes and local factors influencing adverse maternal outcomes has been identified as a major obstacle hindering appropriate distribution of resources targeted towards improving maternal healthcare. This paper reports the first community based study that measures the incidence of maternal mortality in Ibadan, Nigeria using the indirect sisterhood method and explores the applicability of this method in a community where maternal mortality is not a rare event. A community-based study was conducted in Ibadan using the principles of the sisterhood method developed by Graham et al. for developing countries. Using a multi-stage sampling design with stratification and clustering, 3,028 households were selected. All persons approached agreed to take part in the study (a participation rate of 100%), with 2,877 respondents eligible for analysis. There was a high incidence of maternal mortality in the study setting: 1,324/6,519 (20.3%) sisters of the respondents had died, with 1,139 deaths reportedly related to pregnancy, childbirth or the puerperium. The MMR was 7,778 per 100,000 live births (95% CI 7,326-8,229). Adjusted for a published Total Fertility Rate of 6.0, the MMR was 6,525 per 100,000 live births (95% CI 6,144-6,909). Women in Ibadan were dying more from pregnancy related complications than from other causes. Findings of this study have implications for midwifery education, training and practice and for the first time provide policy makers and planners with information on maternal mortality in the community of Ibadan city and shed light on the causes of maternal mortality in the area.


Asunto(s)
Mortalidad Materna , Hermanos , Adolescente , Adulto , Métodos Epidemiológicos , Femenino , Humanos , Incidencia , Entrevistas como Asunto , Persona de Mediana Edad , Nigeria/epidemiología , Complicaciones del Trabajo de Parto/mortalidad , Vigilancia de la Población , Embarazo , Complicaciones del Embarazo/mortalidad , Resultado del Embarazo/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Factores Socioeconómicos , Encuestas y Cuestionarios , Población Urbana , Adulto Joven
8.
Water Sci Technol ; 67(1): 159-67, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23128634

RESUMEN

A small unit of cogeneration of energy and heat was tested at the Centre for Research and Training on Sanitation UFMG/COPASA - CePTS, located at the Arrudas Sewage Treatment Plant, in Belo Horizonte, Minas Gerais, Brazil. The unit consisted of an engine power generator adapted to run on biogas, a thermal dryer prototype and other peripherals (compressor, biogas storage tank, air blower, etc.). The heat from engine power generator exhaust gases was directed towards the thermal dryer prototype to dry the sludge and disinfect it. The results showed that the experimental apparatus is self-sufficient in electricity, even producing a surplus, available for other uses. The tests of drying and disinfection of sludge lasted 7 h, leading to an increase in solids content from 4 to 8% (50% reduction in sludge volume). Although the drying of sludge was not possible (only thickening was achieved), the disinfection process proved very effective, enabling the complete inactivation of helminth eggs.


Asunto(s)
Fuentes de Energía Bioeléctrica , Biocombustibles , Calor , Aguas del Alcantarillado , Eliminación de Residuos Líquidos/métodos , Reactores Biológicos , Agua , Purificación del Agua
9.
ACS Omega ; 8(8): 7956-7967, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36872960

RESUMEN

The persistent increase in the amount of nonsteroidal anti-inflammatory drugs such as ibuprofen (IBP) and diclofenac (DCF) in water bodies is alarming, thereby calling for a need to be addressed. To address this challenge, a bimetallic (copper and zinc) plantain-based adsorbent (CZPP) and reduced graphene oxide modified form (CZPPrgo) was prepared by facile synthesis for the removal of ibuprofen (IBP) and diclofenac (DCF) in water. Both the CZPP and CZPPrgo were characterized by different techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), and pHpzc analysis. FTIR and XRD confirmed the successful synthesis of the CZPP and CZPPrgo. The adsorption of the contaminants was carried out in a batch system, and several operational variables were optimized. The adsorption is affected by the initial concentration of the pollutants (5-30 mg·L-1), the adsorbent dose (0.05-0.20 g), and pH (2.0-12.0). The CZPPrgo has the best performance with maximum adsorption capacities of 148 and 146 mg·g-1 for removing IBP and DCF from water, respectively. The experimental data were fitted into different kinetic and isotherm models; the removal of IBP and DCF follows the pseudo-second order, which can be best explained by the Freundlich isotherm model. The reuse efficiency was above 80% even after four adsorption cycles. This shows that the CZPPrgo is a promising adsorbent for removing IBP and DCF in water.

10.
Environ Sci Pollut Res Int ; 30(31): 76798-76817, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37246181

RESUMEN

This study reports the occurrence and risk assessment of 2,4-dinitrophenol (2,4-DNP), phenol (PHE), and 2,4,6-trichlorophenol (2,4,6-TCP) in drinking water sources in three south-western States in Nigeria (Osun, Oyo, and Lagos). Groundwater (GW) and surface water (SW) were collected during dry and rainy seasons of a year. The detection frequency of the phenolic compounds followed the trend Phenol > 2,4-DNP > 2,4,6-TCP. The mean concentrations of 2,4-DNP, Phenol, and 2,4,6-TCP in GW/SW samples from Osun State were 639/553 µg L-1, 261/262 µg L-1, and 169/131 µg L-1 during the rainy season and 154/7 µg L-1, 78/37 µg L-1, and 123/15 µg L-1 during the dry season, respectively. In Oyo State, the mean concentrations were 165/391 µg L-1 for 2,4-DNP and 71/231 µg L-1 for Phenol in GW/SW samples, respectively, during the rainy season. Generally, in the dry season, these values decreased. In any case, these concentrations are higher than those previously reported in water from other countries. The concentration of 2,4-DNP in water posed serious ecological risks to Daphnia on the acute scale while it was algae on the chronic scale. Estimated daily intake and hazard quotient calculations suggest that 2,4-DNP and 2,4,6-TCP in water pose serious toxicity concerns to humans. Additionally, the concentration of 2,4,6-TCP in water from Osun State in both seasons of the year and in both groundwater and surface water poses significant carcinogenic risks to persons ingesting water from these sources in the State. Every exposure group studied were at risk from ingesting these phenolic compounds in water. However, this risk decreased with increasing age of the exposure group. Results from the principal component analysis indicate that 2,4-DNP in water samples is from an anthropogenic source different from that for Phenol and 2,4,6-TCP. There is a strong need to treat water from GW and SW systems in these States before ingesting while assessing their quality regularly.


Asunto(s)
Agua Potable , Agua Subterránea , Fenoles , Contaminantes Químicos del Agua , Humanos , 2,4-Dinitrofenol/análisis , Agua Potable/análisis , Monitoreo del Ambiente , Nigeria , Fenol/análisis , Fenoles/análisis , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
11.
Scand J Med Sci Sports ; 22(5): e86-92, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22830442

RESUMEN

Studies have investigated the effect of exercise on prostate cancer risk. However, there are still doubts regarding the correlation between physical activity and the steroid hormones with respect to the reduction of the risk for prostatic lesions. We evaluated the levels of corticosterone, dihydrotestosterone (DHT), testosterone, estradiol, and steroid hormone receptors, and investigated the relationship between apoptosis and cell proliferation in the rat ventral prostate after training. Two groups were included in this study: control and trained. The trained group was submitted to training for 13 weeks (1 week of adaptation). Two days after the last training session, all animals were euthanized, and the intermediate and distal regions of the ventral prostate were collected and processed for immunohistochemistry, Western blotting and hormonal analyses. Physical exercise increased the corticosterone plasma, DHT and testosterone. In addition, androgen receptor expression was lower and estrogen receptor (ER) α and ER ß expression were higher in the trained group. However, the trained group showed disruption of the ratio of apoptotic to proliferating cells, indicating a predominance of apoptosis. We conclude that physical exercise alters the sex hormones and their receptors and is associated with the disruption of the balance between apoptosis and cell proliferation in the rat ventral prostate.


Asunto(s)
Apoptosis/fisiología , Proliferación Celular , Hormonas Esteroides Gonadales/fisiología , Condicionamiento Físico Animal/fisiología , Próstata/fisiología , Neoplasias de la Próstata/patología , Animales , Corticosterona/sangre , Dihidrotestosterona/sangre , Modelos Animales de Enfermedad , Estradiol/sangre , Masculino , Próstata/patología , Enfermedades de la Próstata/sangre , Ratas , Ratas Wistar , Testosterona/sangre
12.
J Dent Res ; 101(2): 151-157, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34515563

RESUMEN

Periodontitis is characterized by alveolar bone loss leading to tooth loss. A small proportion of patients develop severe periodontitis at the juvenile or adolescent age without exposure to the main risk factors of the disease. It is considered that these cases carry rare variants with large causal effects, but the specific variants are largely unknown. In this study, we performed exome sequencing of 5 families with children who developed stage IV, grade C, periodontitis between 3 and 18 y of age. In 1 family, we found compound heterozygous variants in the gene CTSC (p.R272H, p.G139R), 1 of which was previously identified in a family with prepubertal periodontitis. Subsequent targeted resequencing of the CTSC gene in 24 patients <25 y of age (stage IV, grade C) identified the known mutation p.I453V (odds ratio = 4.06, 95% CI = 1.6 to 10.3, P = 0.001), which was previously reported to increase the risk for adolescent periodontitis. An affected sibling of another family carried a homozygous deleterious mutation in the gene TUT7 (p.R560Q, CADD score >30 [Combined Annotation Dependent Depletion]), which is implicated in regulation of interleukin 6 expression. Two other affected siblings shared heterozygous deleterious mutations in the interacting genes PADI1 and FLG (both CADD = 36), which contribute to the integrity of the environment-tissue barrier interface. Additionally, we found predicted deleterious mutations in the periodontitis risk genes ABCA1, GLT6D1, and SIGLEC5. We conclude that the CTSC variants p.R272H and p.I453V have different expressivity and diagnostic relevance for prepubertal and adolescent periodontitis, respectively. We propose additional causal variants for early-onset periodontitis, which also locate within genes that carry known susceptibility variants for common forms. However, the genetic architecture of juvenile periodontitis is complex and differs among the affected siblings of the sequenced families.


Asunto(s)
Periodontitis Agresiva , Adolescente , Periodontitis Agresiva/genética , Catepsina C/genética , Exoma/genética , Humanos , Mutación , Linaje , Análisis de Secuencia de ADN , Secuenciación del Exoma
13.
Heliyon ; 8(12): e12610, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36593848

RESUMEN

Although nanotube is among the most effective morphology of Titania due to its unilateral pathway for photo-generated charge transfer and mechanical stability, its performance is still hampered by high recombination. In the present study, to further improve the photocatalytic degradation performance of Titania, univalent elements of H and Na were respectively ion-exchanged into the Titania nanotubes (TNTs). The photocatalyst was characterized using XRD, TEM, ICP-AES, and FTIR. The modified samples displayed enhanced photocatalytic degradation performance over Degussa TiO2 under UV-A light illumination of MB. The rate constants of NaTNT and HTNT were 16 and 13 times that of Degussa TiO2. Specifically, the Na-TNTs showed better photocatalytic degradation activity than H-TNTs with a rate constant of 0.12 min-1 while the latter showed 0.09 min-1. The optimum adsorption and photocatalytic performance of NaTNT were determined at pH 6 achieving about 99% MB removal within 10 min of irradiation. The ion exchange NaTNT displayed excellent reusability after the fifth cycle of the photocatalytic tests and superoxide radicals were experimentally determined to be the main reactive oxygen species involved in the photocatalytic degradation of MB.

14.
Curr Aging Sci ; 15(1): 2-25, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33653258

RESUMEN

BACKGROUND: Alzheimer's Disease (AD) is the most common cause of dementia. Genetics, excessive exposure to environmental pollutants, as well as unhealthy lifestyle practices are often linked to the development of AD. No therapeutic approach has achieved complete success in treating AD; however, early detection and management with appropriate drugs are key to improving prognosis. INTERVENTIONS: The pathogenesis of AD was extensively discussed in order to understand the reasons for the interventions suggested. The interventions reviewed include the use of different therapeutic agents and approaches, gene therapy, adherence to healthy dietary plans (Mediterranean diet, Okinawan diet and MIND diet), as well as the use of medicinal plants. The potential of nanotechnology as a multidisciplinary and interdisciplinary approach in the design of nano-formulations of AD drugs and the use of Superparamagnetic Iron Oxide Nanoparticles (SPIONs) as theranostic tools for early detection of Alzheimer's disease were also discussed.


Asunto(s)
Enfermedad de Alzheimer , Dieta Mediterránea , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/etiología , Diagnóstico Precoz , Humanos
15.
Eur Phys J E Soft Matter ; 34(1): 10, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21337078

RESUMEN

In this work we investigate the influence of the adsorption of ions on the impedance spectroscopy of an electrolytic cell. We consider that the positive and negative ions present in a dielectric liquid are adsorbed in the electrode surfaces with different adsorption energies. This difference in adsorption energies causes an additional plateaux in the limit of the low-frequency range of the real part of the impedance Z. In the same frequency range, a second minimum in the imaginary part of Z is predicted. The theory is illustrated with measurements of the impedance of an electrolytic solution in the frequency range from 10(-2) Hz to 1 KHz. A comparison between the present model and others from the literature to describe the experimental results is also made.


Asunto(s)
Espectroscopía Dieléctrica/métodos , Electrólisis/métodos , Adsorción , Electrodos , Modelos Teóricos , Cloruro de Potasio/química , Propiedades de Superficie
16.
Sci Total Environ ; 792: 148092, 2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34147811

RESUMEN

Parabens are biocides used as preservatives in food, cosmetics and pharmaceuticals. They possess antibacterial and antifungal activity due to their ability to disrupt cell membrane and intracellular proteins, and cause changes in enzymatic activity of microbial cells. Water, one of our most valuable natural resource, has become a huge reservoir for parabens. Halogenated parabens from chlorination/ozonation of water contaminated with parabens have shown to be even more persistent in water than other types of parabens. Unfortunately, there is dearth of data on their (halogenated parabens) presence and fate in groundwater which serves as a major source of drinking water for a huge population in developing countries. An attempt to neglect the presence of parabens in water will expose man to it through ingestion of contaminated food and water. Although there are reviews on the occurrence, fate and behaviour of parabens in the environment, they largely omit toxicity and removal aspects. This review therefore, presents recent reports on the acute and chronic toxicity of parabens, their estrogenic agonistic and antagonistic activity and also their relationship with antimicrobial resistance. This article further X-rays several techniques that have been employed for the removal of parabens in water and their drawbacks including adsorption, biodegradation, membrane technology and advanced oxidation processes (AOPs). The heterogeneous photocatalytic process (one of the AOPs) appears to be more favoured for removal of parabens due to its ability to mineralize parabens in water. However, more work is needed to improve this ability of heterogeneous photocatalysts. Perspectives that will be relevant for future scientific studies and which will drive policy shift towards the presence of parabens in our drinking waters are also offered. It is hoped that this review will elicit some spontaneous actions from water professionals, scientists and policy makers alike that will provide more data, effective technologies, and adaptive policies that will address the growing threat of the presence of parabens in our environment with respect to human health.


Asunto(s)
Cosméticos , Purificación del Agua , Humanos , Parabenos/toxicidad , Conservadores Farmacéuticos , Agua
17.
Heliyon ; 6(4): e03763, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32346632

RESUMEN

Iron (III) thioselenoimidodiphosphinate complex, Fe{(SePPh2NPPh2S)2N}3], was synthesized from the ligand [Ph2P(S)HNP(Se)Ph2], and the complex employed as the combined source of the targeted elements (Fe and Se) to generate orthorhombic FeSe2. This was achieved by thermolysis using a quartz glass tube, under reduced pressure at 500 °C during 1 h 30 min. The crystalline product was revealed by X-ray diffraction (XRD), while the morphology consisted of polygonal crystallites according to the scanning electron microscopy (SEM) studies. Superconducting quantum interference device (SQUID) measurements on the material confirmed its ferromagnetism as observed from the magnetization curve, indicated by the field-cooled and zero field-cooled conditions under a magnetic field of 100 Oe. This ferromagnetic material, FeSe2 finds useful application in producing electrical semiconductors.

18.
Toxicol Res ; 36(1): 45-58, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31998625

RESUMEN

Food toxicity assessment was made for frequently consumed canned foods in Nigeria in order to estimate potential human health risks associated with their consumption. Levels of heavy metals (Pb, Cd, As, Fe, Mn and Zn), Nitrate and Nitrite, pH and salt were assessed in randomly purchased samples from groceries stores to represent what is readily available on the market. Nitrates and nitrites were assessed using a Perkin-Elmer spectrophotometer while heavy metal levels were determined using Atomic absorption spectrophotometer. Human health risk was estimated using standard indices; estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI) and dietary exposure (DE). Results showed varying concentrations of nitrates, nitrites, heavy metals, in all the canned food categories but the level of salt and pH seemed constant. Nitrate, Fe and Cd in all the canned food categories exceeded recommended limit set by EU. Health risk estimations showed EDI values for Cd in all the canned food categories above the tolerable daily intake, while DE for Fe in canned sweet corn, Fe, Zn and Pb in canned beans/peas had values above recommended limits. THQ values for all the canned foods were above 1 in the canned beans/peas while HI was above 1 in the canned fish category. The study revealed the potential for Cd toxicity and risk of non-carcinogenic health effects from canned beans/peas consumption. Constant monitoring of canned foods is therefore imperative considering the growing demand for canned products due to changing lifestyle.

19.
Environ Sci Pollut Res Int ; 27(9): 9957-9969, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31927738

RESUMEN

The Sustainable Development Goal 6 (SDG #6) of the United Nations (UN) is hinged on the provision, availability, and sustainability of water for the global populace by 2030. In a bid to achieve this goal, the quest to seek for ubiquitous and low-cost adsorbents to treat effluents laden with industrial dyes, such as methylene blue (MB), is on the increase in recent years. Acute exposure of humans to (MB) dye causes cyanosis, necrosis, and jaundice and even leads to death. In this research, zinc-modified hybrid clay composite adsorbent (materials from kaolinite and biomass (crushed Carica papaya seeds and/or plantain peel)) was developed via microwave route. This adsorbent was characterized using field emission scanning electron microscopy (FE-SEM), Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray (EDX), and high-resolution transmission electron microscopy (HR-TEM). These characterization techniques confirmed the success achieved in doping hybrid clay with Zn. These adsorbents were used to sequester cationic dye (MB) from aqueous solutions and textile effluent under various experimental conditions. The adsorption and desorption data obtained were analyzed using various kinetic models, which are two-step kinetics, pseudo-first order, pseudo-second order, fractal kinetics, first-order desorption, second-order desorption, and modified statistical rate theory (MSRT) desorption models. Results showed that the adsorption of the dye occurred via several chemical interactions, while the latter models (for desorption) indicated that desorption occurred in two different desorption sites on the adsorbent surfaces, which showed that the adsorption of MB dye onto the adsorbents was stable without the emergence of any secondary pollution. Adsorption of MB was achieved within 15 min for aqueous solutions and 900 min for textile effluent, which is an improvement on previous results from other studies. The three adsorption-desorption cycles for MB uptake by the adsorbents showed that it is pragmatically applicable to treat textile effluents. Hence, low-cost composite adsorbents have a potential for the effective remediation of MB dye from textile effluents as this study confirmed.


Asunto(s)
Arcilla , Contaminantes Químicos del Agua , Adsorción , Colorantes , Concentración de Iones de Hidrógeno , Cinética , Azul de Metileno , Microondas
20.
Biochem Biophys Rep ; 24: 100837, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33251341

RESUMEN

Postprandial hyperglycemia has orchestrated untimely death among diabetic patients over the decades and regulation of α-amylase activity is now becoming a promising management option for type 2 diabetes. The present study investigated the binding interactions of three structurally diverse dichalcogenoimidodiphosphinate ligands with α-amylase to ascertain the affinity of the ligands for α-amylase using spectroscopic and molecular docking methods. The ligands were characterized using 1H and 31P NMR spectroscopy and CHN analysis. Diselenoimidodiphosphinate ligand (DY300), dithioimidodiphosphinate ligand (DY301), and thioselenoimidodiphosphinate ligand (DY302) quenched the intrinsic fluorescence intensity of α-amylase via a static quenching mechanism with bimolecular quenching constant (Kq) values in the order of x1011 M-1s-1, indicating formation of enzyme-ligand complexes. A binding stoichiometry of n≈1 was observed for α-amylase, with high binding constants (Ka). α-Amylase inhibition was as follow: Acarbose > DY301>DY300>DY302. Values of thermodynamic parameters obtained at temperatures investigated (298, 304 and 310 K) revealed spontaneous complex formation (ΔG<0) between the ligands and α-amylase; the main driving forces were hydrophobic interactions (with DY300, DY301, except DY302). UV-visible spectroscopy and Förster resonance energy transfer (FRET) affirmed change in enzyme conformation and binding occurrence. Molecular docking revealed ligands interaction with α-amylase via some key catalytic site amino acid residues (Asp197, Glu233 and Asp300). DY301 perhaps showed highest α-amylase inhibition (IC50, 268.11 ±â€¯0.74 µM) due to its moderately high affinity and composition of two sulphide bonds unlike the others. This study might provide theoretical basis for development of novel α-amylase inhibitors from dichalcogenoimidodiphosphinate ligands for management of postprandial hyperglycemia.

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