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3.
Int J Biol Macromol ; 270(Pt 2): 132486, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38763238

RESUMEN

Naproxen (NPX) as an emerging anthropogenic contaminant was detected in many water sources, which can pose a serious threat to the environment and human health. Peroxymonosulfate (PMS) decomposed by Cu(I) has been considered an effective activation method to produce reactive species. However, this decontamination process is restricted by the slow transformation of Cu(II)/Cu(I) by PMS. Herein, new N-(L-cysteine/triazine)-O-(carboxymethyl)-chitosan/cobalt ferrate-rice hull hybrid biocomposite was constructed to anchor the mixed-valent Cu(I)-Cu (II) (CuI, II-CCCF) for removing pharmaceutical pollutants (i.e., naproxen, ciprofloxacin, tetracycline, levofloxacin, and paracetamol). The structural, morphological, and catalytic properties of the CuI,II-CCCF have been fully identified by a series of physicochemical characterizations. Results demonstrated that the multifunctional, hydrophilic character, and negative ζ-potential of the activator, accelerating the redox cycle of Cu(II)/Cu(I) with hydroxyl amine (HA). The negligible metal leaching, well-balanced thermodynamic-kinetic properties, and efficient adsorption-catalysis synergy are the main reasons for the significantly enhanced catalytic performance of CuI,II-CCCF in the removal of NPX (98.6 % at 7.0 min). The main active species in the catalytic degradation of NPX were identified (●OH > SO4●- > 1O2 > > O2●-) and consequently suggested a degradation path. It can be noted that these types of carbohydrate-based nanocomposite offer numerous advantages, encompassing simple preparation, excellent decontamination capabilities, and long-term stability.


Asunto(s)
Quitosano , Cobalto , Cobre , Nanocompuestos , Naproxeno , Contaminantes Químicos del Agua , Quitosano/química , Quitosano/análogos & derivados , Nanocompuestos/química , Cobre/química , Naproxeno/química , Cinética , Catálisis , Adsorción , Cobalto/química , Contaminantes Químicos del Agua/química , Peróxidos/química , Cisteína/química , Purificación del Agua/métodos , Hierro
4.
J Neurosci Methods ; 405: 110104, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38447914

RESUMEN

BACKGROUND: Preclinical models are essential for identifying changes occurring after neurologic injury and assessing therapeutic interventions. Yucatan miniature pigs (minipigs) have brain and spinal cord dimensions like humans and are useful for laboratory-to-clinic studies. Yet, little work has been done to map spinal sensorimotor distributions and identify similarities and differences between the porcine and human spinal cords. NEW METHODS: To characterize efferent and afferent signaling, we implanted a conventional 32-contact, four-column array into the dorsal epidural space over the lumbosacral spinal cord, spanning the L5-L6 vertebrae, in two Yucatan minipigs. Spinally evoked motor potentials were recorded bilaterally in four hindlimb muscles during stimulation delivered from different array locations. Then, cord dorsum potentials were recorded via the array by stimulating the left and right tibial nerves. RESULTS: Utilizing epidural spinal stimulation, we achieved selective left, right, proximal, and distal activation in the hindlimb muscles. We then determined the selectivity of each muscle as a function of stimulation location which relates to the distribution of the lumbar motor pools. COMPARISON WITH EXISTING METHODS: Mapping motoneuron distribution to hindlimb muscles and recording responses to peripheral nerve stimulation in the dorsal epidural space reveals insights into ascending and descending signal propagation in the lumbar spinal cord. Clinical-grade arrays have not been utilized in a porcine model. CONCLUSIONS: These results indicate that efferent and afferent spinal sensorimotor networks are spatially distinct, provide information about the organization of motor pools in the lumbar enlargement, and demonstrate the feasibility of using clinical-grade devices in large animal research.


Asunto(s)
Traumatismos de la Médula Espinal , Médula Espinal , Animales , Humanos , Porcinos , Electromiografía/métodos , Porcinos Enanos , Médula Espinal/fisiología , Vértebras Lumbares , Estimulación Eléctrica
5.
Int J Biol Macromol ; 256(Pt 2): 127863, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37952803

RESUMEN

In view of the feed/foods inevitably contaminated by toxic and carcinogenic aflatoxin B1 (AFB1), efficient mesoporous metformin-chitosan/silica­cobalt ferrite nanospheres (Mt-CS/CFS NSs) was prepared to remove AFB1 from aqueous/non-aqueous media. The morphological, functional, and structural characteristics and adsorption properties of C/N-enriched CS/CFS were investigated systematically. The interactive operating variables (temperature (5.0-35 °C); time (10-100 min); AFB1 dose (50-100 µg/mL); and Mt-CS/CFS dosage (0.5-3.5 mg) were optimized via the Box-Behnken design (BBD), which demonstrated good agreement between the experimental data and proposed model. The adsorption efficiency in artificially contaminated cow's milk as well as aqueous environment reached over 91.0 % in a wide pH range (3.0-9.0), without significant change in the nutritional value of milk. Freundlich isotherm and second-order adsorption kinetics were regarded as the most suitable models to fit the adsorption results, and the adsorption rate is dominated by the intra-particle diffusion and boundary layer diffusion. Thermodynamic analyses proved that the process was spontaneous and exothermic. The adsorption mechanism could be explained as physisorption via hydrogen bonding, n-π interaction, and hydrophobic/hydrophilic interactions. The porous Mt-CS/CFS NS derived from chitosan nanoparticles is therefore outstanding adsorbent, offering great adsorptive performance and recycabilities, which impedes economic losses in the food industry.


Asunto(s)
Quitosano , Cobalto , Compuestos Férricos , Nanosferas , Contaminantes Químicos del Agua , Animales , Aflatoxina B1 , Quitosano/química , Leche , Concentración de Iones de Hidrógeno , Nitrógeno , Termodinámica , Adsorción , Cinética , Contaminantes Químicos del Agua/química , Agua/química
6.
Int J Biol Macromol ; 254(Pt 3): 127897, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37956815

RESUMEN

Due to the high heat and chemical stability of aflatoxin B1 (AFB1) with significant impacts on humans/animals and thus it needs to develop a practical and efficient approach for its removal. Herein, we fabricated a magnetic Pd-chitosan/glutaraldehyde/rice husk/hercynite (Pd@CRH-x) composite for efficient detoxification of AFB1. The Pd@CRH-x was obtained by a simple wet-impregnation procedure of CRH complexes followed by pyrolysis. The results confirmed that the unique structure of Pd@CRH-400 effectively improves dispersity, and mass transfer subsequently enhancing removal efficiency in batch conditions. Results indicate 94.30 % of AFB1 was efficiently degraded by 0.1 mg mL-1 Pd@CRH-400 with 4.0 mM H2O2 at wide pH ranges (3.0-10) at 60 min with a decomposition rate constant of 0.0467 min-1. Besides, by comparing the quality factors of edible oil (i.e., acid value, peroxide value, iodine value, moisture, volatile matters, anisidine value, and fatty acid composition), it was confirmed that there was no obvious influence on the physicochemical indicators of edible oil after removal/storage process. Subsequently, the systematic kinetic study and AFB1 degradation mechanism were presented. This study provides a new strategy for the efficient construction of controllable and dispersed Pd-based catalysts using CRH-x as a spatial support for alleviating the risk of toxic pollutants.


Asunto(s)
Quitosano , Oryza , Humanos , Animales , Aflatoxina B1/química , Peróxido de Hidrógeno , Oryza/química , Fenómenos Magnéticos
7.
RSC Adv ; 13(49): 34739-34754, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-38035230

RESUMEN

Currently, the use of magnetic physical adsorbents for detoxification is widely applied in the food industry; however, the fabrication of high-efficiency low-cost absorbents without damaging the nutritional quality of food is a major challenge. Herein, a simple, green, efficient, and cost-effective method for the magnetic solid-phase extraction of aflatoxin B1 (AFB1) from edible oils and aqueous matrices was developed using a dopamine-loaded biomass chitosan-iron-cobalt spinel oxide nanocomposite (DC/CFOS NC). The characterization, physicochemical processes, mechanism, and reusability of DC/CFOS were systematically evaluated in detail. It was found that the adsorption characteristic of DC/CFOS NC was accurately represented by the pseudo-second-order kinetics (k2 = 0.199 g mg-1 min-1) and Freundlich isotherm models (Kf = 1.139 (mg g-1) (L mg-1), R2 = 0.991)), and its adsorptive process is feasible, spontaneous, and exothermic. Benefiting from its high specific surface area, microporous structure, and polar/non-polar active sites, the as-prepared DC/CFOS exhibited an excellent adsorption performance for AFB1 (50.0 µg mL-1), as measured using the Freundlich isotherm model. The mechanistic studies demonstrated that the synergistic effects of the surface complexation and electrostatic interactions between the functional groups of DC/CFOS NC and AFB1 were the dominant adsorption pathways. Besides, DC/CFOS exhibited negligible impacts on the nutritional quality of the oil after the removal process and storage. Thus, DC/CFOS NC showed sufficient efficacy and safety in the removal of AFB1 from contaminated edible oil.

8.
Int J Biol Macromol ; 234: 123709, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-36801216

RESUMEN

The contamination of foodstuffs with aflatoxins B1 (AFB1) as carcinogen/mutagens toxin produced by Aspergillus fungi that are a major threat to the economy, safe food supply, and human health. To, we present a facile wet-impregnation and co-participation strategies for the construction of a novel superparamagnetic MnFe biocomposite (MF@CRHHT), in which dual metal oxides MnFe were anchored in/on agricultural/forestry residues (chitosan/rice husk waste/hercynite hybrid nanoparticles) and applied for rapid AFB1 detoxification by destroying in a non-thermal/microbial way. Structure, and morphology were comprehensively characterized by various spectroscopic analyses. The AFB1 removal in PMS/MF@CRHHT system followed pseudo-first-order kinetics, and exhibited excellent efficiency (99.3 % in 20 min and 83.1 % in 5.0 min) over a broad pH range (5.0-10.0). Importantly, relationship between high efficiency and physical-chemical properties, and mechanistic insight reveals that the synergistic effect could be related to the formation MnFe bond in MF@CRHHT and then mutual electron transfer between them to enhanced electron density and generate reactive oxygen species. An AFB1 decontamination pathway proposed was based on the free radical quenching experiments and analysis of the degradation intermediates. Thus, the MF@CRHHT can be applied as an efficient, cost-effective, recoverable, environment-friendly and highly efficient biomass-based activator for remediate pollution.


Asunto(s)
Quitosano , Oryza , Humanos , Aflatoxina B1/química , Oryza/química , Nanopartículas Magnéticas de Óxido de Hierro
9.
Public Health ; 200: 116-123, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34717165

RESUMEN

OBJECTIVES: Several popular cardiovascular risk assessment tools have been developed in Western countries; however, the predictive abilities of these tools have not been evaluated in Middle Eastern countries. The present study aimed to determine the abilities of cardiovascular risk assessment tools in a population-based study in Northern Iran. STUDY DESIGN: Population-based cohort study in Northern Iran. METHODS: In total, 2883 individuals (1629 men and 1254 women), aged 40-74 years, were included in the study. We determined the predictive abilities of the American College of Cardiology/American Heart Association (ACC/AHA) risk prediction tool, the Framingham general cardiovascular risk profile in primary care settings, and the Systematic Coronary Risk Evaluation (SCORE) equations for low- and high-risk European countries. Receiver operating characteristic (ROC) analysis was used to determine the predictive abilities of these four risk assessment tools. RESULTS: Based on areas under curve (AUC) values and related 95% confidence intervals (95% CIs), the discriminative abilities of the ACC/AHA tool, the Framingham approach, and the SCORE for low- and high-risk European countries to estimate non-fatal cardiovascular disease (CVD) events were 0.6625, 0.6517, 0.6476 and 0.6458, respectively, in men, and 0.7722, 0.7525, 0.7330 and 0.7331, respectively, in women. Moreover, the abilities of these four tools to estimate fatal CVD events were found to be 0.8614, 0.8329, 0.7996 and 0.7988 in men, and 0.8779, 0.8372, 0.8535 and 0.8518 in women, respectively. CONCLUSIONS: The cardiovascular risk assessment tools investigated in this study showed acceptable predictive abilities in women. The ACC/AHA approach showed slightly better performance compared with the SCORE tool; however, the SCORE tool benefited from the lowest cost compared with all the other tools.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedades Cardiovasculares/epidemiología , Estudios de Cohortes , Europa (Continente) , Femenino , Humanos , Irán/epidemiología , Masculino , Medición de Riesgo , Factores de Riesgo , Estados Unidos
10.
Mymensingh Med J ; 28(4): 881-886, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31599255

RESUMEN

This case control study was conducted in the out patient department (OPD), Enam Medical College & Hospital (EMCH), Dhaka, Bangladesh from 1st January 2017 to 31st December 2017. The aim of our study was to find the possible association between serum iron state and iron deficiency anemia with bronchial asthma in women. We investigated 40 diagnosed female cases of well controlled bronchial asthma and 20 healthy female as control. In both groups complete blood count (CBC) with peripheral smear was done, C-reactive protein (CRP), serum iron, serum ferritin, and serum total iron binding capacity (TIBC) was measured. We found asthma cases had lower hemoglobin than control (mean±SD 10.92±1.34 vs. 12.30±0.73, p value 0.013), serum iron and serum ferritin were significantly lower (p value 0.016 and 0.000 respectively) and TIBC was higher (p value 0.000) in asthmatic cases as compared to controls. Non anemic asthmatics showed significant lower serum ferritin compared with non-anemic healthy controls (p value 0.005). So we conclude that iron deficiency anemia is more prevalent in asthmatic women as compared to healthy controls.


Asunto(s)
Anemia Ferropénica/epidemiología , Asma/epidemiología , Bangladesh/epidemiología , Estudios de Casos y Controles , Femenino , Ferritinas , Hemoglobinas , Humanos
11.
Mymensingh Med J ; 28(4): 906-913, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31599259

RESUMEN

Chronic kidney disease and the methods of its treatment play an important part in shaping the Quality of Life QOL of patients receiving dialysis. KDQOL™-36 is the most widely used instrument to evaluate health related quality of life of chronic kidney disease patients. The aim of the study was the subjective assessment of the quality of life (QOL) of patients treated with hemodialysis and also to understand the distribution of component scores of the scale with distribution of responses to individual items of the scale among the selected sample. This cross sectional study was conducted among randomly selected 151 patients of chronic kidney disease receiving hemodialysis with pre-dialysis proper education at Inpatient Department in National Institute of Kidney Diseases and Urology (NIKDU), Dhaka, Bangladesh during the period of June 2018 to December 2018. The instrument to measure the QOL was Kidney Disease and Quality of Life Bangla version 36 (KDQOL™-36). Recruited patients were interviewed with questionnaire technique to collect data with the scale which is a structured questionnaire comprised of four subscales. Mean scores ±SD of the domain of the physical and mental component summary, burden of kidney disease, symptoms and problems of kidney disease and effects of kidney disease subscales were 29.3±16.03, 16.93±13.0, 81.09±13.14 and 61.67±13.84 respectively. The mean ±SD of the combined score for all the four domains was 47.24±11.52. The rate of those with impaired QOL (mean score <66.7) was 96.7%. The most bothersome domain was burden of the kidney disease domain, where the mean scores of all the items were below 66.7. The study provides information that regular pre-dialysis attendance helps to provide the patient with proper education and thereby achieve better QOL among patients of chronic kidney disease receiving hemodialysis. By using the KDQOL™-36 scale this study finds that the domain of symptom of the kidney disease appeared to have least effect on the quality of life as the mean scores ranged higher from other subscales and in most cases the scores were above 66.7.


Asunto(s)
Fallo Renal Crónico , Insuficiencia Renal Crónica , Bangladesh , Estudios Transversales , Humanos , Calidad de Vida , Diálisis Renal , Encuestas y Cuestionarios
12.
J Colloid Interface Sci ; 483: 118-131, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27552420

RESUMEN

In this work synthesis of Mn-nanoparticles (MnNPs) supported on the Schiff base modified nano-sized SiO2Al2O3 mixed-oxides (Si/Al) and its implementation as an adsorbent for the removal of organic pollutions such as methyl orange (MO) and salicylic acid (SA) was investigated. Si/Al were functionalized by grafting Schiff base ligand and in the next step, MnNPs were prepared over the modified nano sol-gel Si/Al. Structures and adsorption characteristics of the obtained organometallic-modified SiO2/Al2O3 mixed oxide were studied by several methods such as elemental analysis, diffuse reflectance UV-vis spectroscopy, FT-IR spectroscopy, nitrogen adsorption/desorption, scanning electron microscope (SEM), transmission electron microscope (TEM), energy dispersive X-ray (EDX), inductively coupled plasma (ICP-AES), Electron Paramagnetic Resonance (EPR), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). EPR data of the immobilized manganese ions resulted that the transition state of active sites in the nano-adsorbent are in the form of Mn(II) ions at the surface. The adsorption properties of heterogeneous Mn(II) ions showed that this nano-adsorbent has very good potential to remove MO and SA ions from aqueous solution. The removal efficiency of the SAPAS@MnNPs towards MO reached out to 89.3 and 29.1% and for SA approached to 54.6 and 18.9% at 150 and 500mg/dm(3) initial organic pollution concentrations, respectively. To investigate the adsorption kinetic of Mn(II) ions onto the nano-sized support, pseudo first and pseudo second order kinetics, and the Freundlich, Langmuir and Langmuir-Freundlich isotherm models have also been applied to the equilibrium adsorption data. The contact time to obtain equilibrium for maximum adsorption capacity was 45min. The adsorption process was spontaneous and endothermic in nature and it was well explained with pseudo-second-order kinetic model. No remarkable loss of removal capacity even after 8th times regeneration was obtained, implying that the immobilized MnNPs has high solidity through the regeneration process. Finally, the mechanism of the MO adsorption process as a model has been studied by the CV, EIS and FTIR techniques. The electrochemical results showed that the oxidation of Mn(II) was easier and took place at lower potentials in the presence of MO, where the electron density at SAPAS@MnNP is higher, consequently reduction of Mn(III) to Mn(II) is more favored. These results suggest that the surface of SAPAS@MnNP was interacted and complexed by MO therefore accelerates electron transfer rate of the reaction related to Mn(II)/Mn(III) redox couple.

13.
J Colloid Interface Sci ; 446: 11-23, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25646786

RESUMEN

The synthesis and growth behavior of the chemically modified ostrich bone wastes as bioadsorbents for the removal of methyl orange from aqueous solutions have been investigated. The ostrich bone wastes were treated with cetyltrimethylammonium bromide (CTABr) and sodium dodecyl benzene sulfonate (SDBS). The synthesized biomaterials were characterized by several physicochemical techniques. The modified ostrich bone with CTABr was found to be effective as adsorbent for the removal of methyl orange (MO) from aqueous solutions. The effect of the experimental conditions on the adsorption behavior was studied by varying the contact time, initial MO concentration, temperature, initial pH, chemical modification process, and amount of adsorbent. The contact time to attain equilibrium for maximum adsorption (90%) was found to be 50 min. The adsorption kinetics of MO has been studied in terms of pseudo-first- and -second-order kinetics, and the Freundlich, Langmuir and Langmuir-Freundlich isotherm models have also been applied to the equilibrium adsorption data. The adsorption process was spontaneous and endothermic in nature and followed pseudo-second-order kinetic model.


Asunto(s)
Compuestos Azo/química , Bencenosulfonatos/química , Huesos/química , Compuestos de Cetrimonio/química , Colorantes/química , Indicadores y Reactivos/química , Adsorción , Compuestos Azo/aislamiento & purificación , Cetrimonio , Carbón Orgánico/química , Concentración de Iones de Hidrógeno , Indicadores y Reactivos/aislamiento & purificación , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termodinámica
14.
J Colloid Interface Sci ; 440: 91-101, 2015 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-25460694

RESUMEN

This article describes the preparation of a nanoadsorbent containing Co-nanoparticles decorated functionalized SiO2-Al2O3 mixed-oxides as a scavenger toward removal of methyl orange. SiO2-Al2O3 mixed-oxides were functionalized with pyridine-2-carbaldehyde and thereafter, in the next step, Co-nanoparticle was prepared over the modified mixed-oxides. The as-prepared nanoadsorbent was characterized by Fourier transform infrared (FTIR), UV-visible diffuse reflectance spectra (UV-vis DRS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), Brunauer-Emmett-Teller (BET), transmission electron microscopy (TEM), electron paramagnetic resonance (EPR), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Results showed that Co-nanoparticle with average size of about 5-25 nm was immobilized successfully on the surface of modified mixed-oxides and was widely dispersed. EPR and CV of Si/Al-PAEA=PyCA@CoNP confirmed that most of the covalently bond active sites of the nano-adsorbent are in the form of Co(II) ions. The supported cobalt is a suitable and efficient adsorbent for the removal of methyl orange from aqueous solution. The heterogeneous Co-NPs were found to be effective adsorbent for the removal of methyl orange ions from solution. The adsorption process was spontaneous and endothermic in nature and followed pseudo-second-order kinetic model. The CV and EIS of the Co-NPs-MO indicates an easily oxidizable environment, this being in agreement with the FTIR data, where the electron density at Co-NPs is higher due to the presence of a donor-electron ligand (methyl orange), that is, reduction of Co-NPs from +3 to +2 oxidation state is more favored.


Asunto(s)
Silicatos de Aluminio/química , Colorantes/aislamiento & purificación , Nanopartículas del Metal/química , Espectroscopía Dieléctrica , Espectroscopía de Resonancia por Spin del Electrón , Cinética , Microscopía Electrónica de Transmisión , Soluciones , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Agua/química
15.
J Colloid Interface Sci ; 440: 189-97, 2015 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-25460705

RESUMEN

Heterogeneous Mn nanoparticles (5-30 nm diameter) is found to be a nanomaterial for the rapid removal of large quantities of toxic dye (methyl orange) from aqueous solution, with wide ranging potential applications. The synthesized materials were characterized with different methods such as FT-IR spectroscopy, CHN elemental analysis, BET, SEM, TEM, ICP-OES and EPR. The contact time to obtain equilibrium for maximum adsorption of methyl orange was 20 min. EPR of Mn ions evidenced that most of the covalently bond active sites of the nano-adsorbent are in the form of Mn(III) ions at the surface. The heterogeneous Mn(III)-Cl ions were found to be effective adsorbent for the removal of methyl orange from solution. The adsorption of methyl orange ions has been studied in terms of pseudo-first-order and pseudo-second-order kinetics, and the Freundlich, Langmuir and Langmuir-Freundlich isotherm models have also been applied to the equilibrium adsorption data. The adsorption process was spontaneous and endothermic in nature and followed pseudo-second-order kinetic model.


Asunto(s)
Compuestos Azo/química , Manganeso/química , Nanotecnología , Adsorción , Espectroscopía de Resonancia por Spin del Electrón , Microscopía Electrónica/métodos , Espectroscopía Infrarroja por Transformada de Fourier
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