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1.
Biochem Biophys Rep ; 38: 101662, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38375421

RESUMO

This study aimed to investigate the effects of swimming in cold water on the release of FGF21 from various tissues and its impact on fat metabolism. Twenty Wistar rats were randomly divided into three groups: untrained (C), trained in thermo-neutral water (TN, 30 °C) and trained in cold water (TC, 15 °C). The training groups swam intervals (2-3 min) until exhaustion, 1 min rest, three days a week for six weeks, with 3-6% bodyweight load. The mRNA expression of variables was determined in white fat tissue (WAT), and FGF21 protein was also measured in the liver, brown fat tissue (BAT), serum, and muscle. The experimental protocols resulted in lower body weight gain, associated with reduced WAT volume; the most remarkable improvement was observed in the TC group. Swimming significantly increased FGF21 protein levels in WAT, BAT, and muscle tissues compared to the C group; substantial increases were in the TC group. Changes in FGF21 were highly correlated with the activation of genes involved in fat metabolisms, such as CPT1, CD36, and HSL, and with glycerol in WAT. The findings indicate a positive correlation between swimming in cold water and the activation of genes involved in fat metabolism, possibly through FGF21 production, which was highly correlated with fat-burning genes.

2.
Sci Rep ; 14(1): 1163, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216707

RESUMO

In this study, a split-type photocatalytic membrane reactor (PMR), incorporating suspended graphitic carbon nitride (g-C3N4) as photocatalyst and a layered polymeric composite (using polyamide, polyethersulfone and polysulfone polymers) as a membrane was fabricated to remove tetracycline (TC) from aqueous solutions as the world's second most used and discharged antibiotic in wastewater. The photocatalyst was synthesised from melamine by ultrasonic-assisted thermal polymerisation method and, along with the membrane, was characterised using various methods, including Brunauer-Emmett-Teller analysis (BET), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), Field emission scanning electron microscopy (FESEM), and Ultraviolet-visible spectroscopy (UV-Vis). The PMR process was optimised, using Design-Expert software for tetracycline removal in terms of UV irradiation time, pH, photocatalyst loading, tetracycline concentration, and membrane separation iteration. It was revealed that a membrane-integrated reactor as a sustainable system could effectively produce clean water by simultaneous removal of tetracycline and photocatalyst from aqueous solution. The maximum removal of 94.8% was obtained at the tetracycline concentration of 22.16 ppm, pH of 9.78 with 0.56 g/L of photocatalyst in the irradiation time of 113.77 min after six times of passing membrane. The PMR system showed reasonable reusability by about a 25.8% drop in TC removal efficiency after seven cycles at optimal conditions. The outcomes demonstrate the promising performance of the proposed PMR system in tetracycline removal from water and suggest that it can be scaled as an effective approach for a sustainable supply of antibiotic-free clean water.

3.
Environ Sci Pollut Res Int ; 30(57): 120236-120249, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37938488

RESUMO

The present study reported a green approach for the sonochemical-assisted synthesis (SAS) of copper oxide nanoparticles (CuO NPs) by using the aqueous extract of the Ficus johannis plant. The aqueous extract was obtained using ultrasonic-assisted extraction (15 min, 45 °C) and microwave-assisted extraction (15 min, 450 w). Next, the as-prepared extracts were used in a plant-mediated approach for the green synthesis of CuO NPs. The synthesized CuO NPs have been characterized via different techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), dynamic light scattering (DLS), ultraviolet-visible absorption, photoluminescence, and Fourier-transformed infrared (FT-IR) spectroscopic techniques. As observed, a broad absorption band around 375 nm clarified the successful synthesis of CuO NPs. From the SEM analysis, the average particle size of the prepared CuO NPs was estimated below 50 nm. In addition, the antimicrobial, antioxidant, and antifungal properties of the aqueous extracts as well as the as-prepared CuO NPs were evaluated by different assays. These included the release of protein, nucleic acids, disk diffusion method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), and time-killing assays.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Cobre/química , Antibacterianos/química , Nanopartículas Metálicas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Óxidos , Difração de Raios X , Testes de Sensibilidade Microbiana
4.
Front Med (Lausanne) ; 10: 1244298, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37828948

RESUMO

Regulatory T cells (Tregs), possess a pivotal function in the maintenance of immune homeostasis. The dysregulated activity of Tregs has been associated with the onset of autoimmune diseases and cancer. Hence, Tregs are promising targets for interventions aimed at steering the immune response toward the desired path, either by augmenting the immune system to eliminate infected and cancerous cells or by dampening it to curtail the damage to self-tissues in autoimmune disorders. The activation of Tregs has been observed to have a potent immunosuppressive effect against T cells that respond to self-antigens, thus safeguarding our body against autoimmunity. Therefore, promoting Treg cell stability presents a promising strategy for preventing or managing chronic inflammation that results from various autoimmune diseases. On the other hand, Tregs have been found to be overactivated in several forms of cancer, and their role as immune response regulators with immunosuppressive properties poses a significant impediment to the successful implementation of cancer immunotherapy. However, the targeting of Tregs in a systemic manner may lead to the onset of severe inflammation and autoimmune toxicity. It is imperative to develop more selective methods for targeting the function of Tregs in tumors. In this review, our objective is to elucidate the function of Tregs in tumors and autoimmunity while also delving into numerous therapeutic strategies for reprogramming their function. Our focus is on reprogramming Tregs in a highly activated phenotype driven by the activation of key surface receptors and metabolic reprogramming. Furthermore, we examine Treg-based therapies in autoimmunity, with a specific emphasis on Chimeric Antigen Receptor (CAR)-Treg therapy and T-cell receptor (TCR)-Treg therapy. Finally, we discuss key challenges and the future steps in reprogramming Tregs that could lead to the development of novel and effective cancer immunotherapies.

5.
Chemosphere ; 336: 139311, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37356592

RESUMO

Antibiotic pollution in water is a growing threat to public health and the environment, leading to the spread of antimicrobial-resistant bacteria. While photocatalysis has emerged as a promising technology for removing antibiotics from water, its limited efficiency in the visible light range remains a challenge. In this study, we present a novel method for the photocatalytic degradation of tetracycline, the second most commonly used antibiotic worldwide, using α-Fe2O3/TiO2 nanocomposites synthesized via rapid sonochemical and wet impregnation methods. The nanocomposites were characterised and tested using a range of techniques, including BET, TEM, FTIR, XRD, FESEM, EDS, and UV-Vis. The RSM-CCD method was also used to optimize the degradation process by varying four key variables (initial concentration, photocatalyst quantity, irradiation time, and pH). The resulting optimized conditions achieved a remarkable degradation rate of 97.5%. We also investigated the mechanism of photodegradation and the reusability of the photocatalysts, as well as the effect of light source operating conditions. Overall, the results demonstrate the effectiveness of the proposed approach in degrading tetracycline in water and suggest that it may be a promising, eco-friendly technology for the treatment of water contaminated with antibiotics.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Catálise , Poluentes Químicos da Água/efeitos da radiação , Tetraciclina , Antibacterianos , Titânio , Água
6.
Int Immunopharmacol ; 117: 109881, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37012882

RESUMO

Immune checkpoint inhibitors (ICIs) have revolutionized cancer immunotherapy, yielding significant antitumor responses across multiple cancer types. Combination ICI therapy with anti-CTLA-4 and anti-PD-1 antibodies outperforms either antibody alone in terms of clinical efficacy. As a consequence, the U.S. Food and Drug Administration (FDA) approved ipilimumab (anti-CTLA-4) plus nivolumab (anti-PD-1) as the first-ever approved therapies for combined ICI in patients with metastatic melanoma. Despite the success of ICIs, treatment with checkpoint inhibitor combinations poses significant clinical challenges, such as increased rates of immune-related adverse events (irAEs) and drug resistance. Thus, identifying optimal prognostic biomarkers could help to monitor the safety and efficacy of ICIs and identify patients who may benefit the most from these treatments. In this review, we will first go over the fundamentals of the CTLA-4 and PD-1 pathways, as well as the mechanisms of ICI resistance. The results of clinical findings that evaluated the combination of ipilimumab and nivolumab are then summarized to support future research in the field of combination therapy. Finally, the irAEs associated with combined ICI therapy, as well as the underlying biomarkers involved in their management, are discussed.


Assuntos
Melanoma , Nivolumabe , Humanos , Ipilimumab/uso terapêutico , Nivolumabe/uso terapêutico , Melanoma/tratamento farmacológico , Terapia Combinada , Imunoterapia/métodos
7.
Artigo em Inglês | MEDLINE | ID: mdl-36740139

RESUMO

The purpose of this study was to investigate whether there is an interacting effect of six weeks of swimming in cold water on the gene expression of browning markers in adipose tissue in rodents. Twenty male Wistar rats were randomly divided into four groups: Control (C, 25 °C), Cold Exposure (CE, 4 °C), Swimming in tepid Water (STW, 30 °C), and Swimming in Cold Water (SCW, 15 °C). The swimming included 2-3 min intervals, 1 min rest, until exhaustion, three days a week for six weeks, with 3 to 6% of bodyweight overload. Rats from CE were exposed to cold for 2 h per day, five days per week. After the experimental protocol, interscapular brown (BAT) and inguinal subcutaneous white (WAT) fat tissues were excised, weighed, and processed for beiging and mitochondrial biogenesis markers gene expression. The experimental protocols resulted in an apparent increase in the number of brown adipocytes (per mm2) in the adipose deposits compared to the C group; substantial changes were observed in the SCW group. Compared to other groups, cold exposure alone increased significantly serum norepinephrine, and also ß2-adrenergic receptor expression was upregulated in the adipocytes compared to the C group. The STW group increased the expression of peroxisome proliferator-activated receptor-γ (PPAR-γ) coactivator-1 alpha (PGC-1α), ß2-adrenergic receptor, and CCAAT/enhancer-binding proteins-α(c/EBP-α) in WAT in comparison with the C group(p < 0.05). In both adipocytes, the SCW intervention significantly upregulated the expression of PGC-1α, PPAR-γ, and c/EBP-α genes in comparison with the C and CE groups. In addition, the expression of TFAM and UCP1 was upregulated substantially in the SCW group compared to other groups. Our data demonstrate that swim training and cold exposure present additive effects in the expression of genes involved in the beiging process and mitochondrial biogenesis markers in BAT and WAT. In addition, it seems that the upregulation of these genes is related to the activation of ß2-adrenergic receptors.


Assuntos
Receptores Ativados por Proliferador de Peroxissomo , Natação , Ratos , Masculino , Animais , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/farmacologia , Tecido Adiposo Marrom/metabolismo , Ratos Wistar , Tecido Adiposo Branco/metabolismo , Termogênese/genética , Água/metabolismo , Água/farmacologia , Receptores Adrenérgicos/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/farmacologia , Temperatura Baixa , Proteína Desacopladora 1/metabolismo
9.
Eur Rev Aging Phys Act ; 19(1): 22, 2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36153484

RESUMO

BACKGROUND: This study aimed to determine the efficacy of functional training with and without blood flow restriction (BFR) on muscle hypertrophy indices and strength in older men. METHODS: Thirty older adults (67.7 ± 5.8 years) were randomly assigned to three groups: functional training (FT), functional training with BFR (FTBFR), and control (C). Participants in experimental groups were trained in three sessions per week for six weeks. They performed 11 whole body exercises, in 2-4 sets of 10 repetitions. FTBFR group wore pneumatic cuffs on their extremities that began with 50% of estimated arterial occlusion pressure which increased by 10% every two weeks. Blood samples were obtained, and static strength tests were evaluated at baseline and after the training program. A One-Way Analysis of Covariance was used to interpret the data. RESULTS: A significant increase in follistatin levels (p = 0.002) and reduction in myostatin levels (p = 0.001) were observed in FT and FTBFR groups; there was a considerable increase in the F:M ratio in both training groups (p = 0.001), whereas it decreased in C group. These changes were accompanied by significant improvements in handgrip (p = 0.001) and shoulder girdle (p = 0.001) strength in both experimental groups, especially in the FTBFR group. However, the levels of irisin were not statistically changed following interventions (p = 0.561). CONCLUSION: The findings showed that FT was effective in increasing circulating biomarkers involved in hypertrophy in older adults while adding BFR to FT had a slight increase in these biomarkers but had a tremendous increase in muscle strength.

10.
Exp Brain Res ; 240(6): 1887-1897, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35460346

RESUMO

The objective was to measure the corticospinal excitability and motoneuron responsiveness of the right and left Biceps Brachii (BB), and left Abductor Digiti Minimi (ADM) muscles in response to submaximal isotonic fatiguing contractions performed by the right BB muscle. With the familiarization session, ten young moderately active male subjects came to the lab on seven occasions. Three sets of 3 min seated elbow curls at 25% of one-repetition maximum (1RM) separated by a 1-min rest performed by the right BB muscle were used as the fatiguing protocol. The motor evoked potential (MEP), cervicomedullary motor evoked potential (CMEP), and compound muscle action potential (Mmax) of the right BB muscle (baseline and after each set of the fatiguing task), the left BB and ADM muscles (baseline, post-fatigue, post-10, and post-20 min) were measured. MEP and CMEP were then normalized to Mmax for statistical analysis. The results showed that in the right BB muscle, there was a significant reduction in the MEP after performing the fatiguing task (p= 0.03), while no significant effect of time was seen in the CMEP (p= 0.07). In the left BB muscle, the MEP significantly decreased from pre-fatigue to post-fatigue (p= 0.01) and post-10 (p= 0.001), while there was a significant decline in the CMEP post-fatigue (p= 0.03). In the left ADM muscle, MEP significantly decreased post-fatigue (p= 0.03) and no changes were seen in the CMEP (p= 0.12). These results not only confirm the incidence of non-local muscle fatigue (NLMF) in response to performing submaximal isotonic fatiguing contractions but also as a new finding, imply that both spinal and supraspinal modulations account for the NLMF response.


Assuntos
Fadiga Muscular , Tratos Piramidais , Estimulação Elétrica/métodos , Eletromiografia/métodos , Potencial Evocado Motor/fisiologia , Humanos , Masculino , Contração Muscular/fisiologia , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Tratos Piramidais/fisiologia , Estimulação Magnética Transcraniana
11.
Chemosphere ; 294: 133705, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35065176

RESUMO

In this study, the effect of three different transition metal ion dopants (Mn2+, Fe2+, and Co2+) on the characteristics of zinc sulfide (ZnS) quantum dots (QDs) was investigated and the obtained QDs photocatalysts were applied for the modification of polysulfone (PSf) mixed matrix membranes to reduce membrane fouling. The synthesized QDs and fabricated membranes were fully identified with SEM, TEM, AFM, FTIR analyses, and also underwent porosity and contact angle tests. Flux recovery ratios (FRR) significantly increased from 69.8% (bare) to 85.0% (1% Fe-doped ZnS QDs) after modification of membranes with metal-doped QDs. The contact angles of the prepared membranes decreased with doping of dissimilar metals, therefore hydrophilicity increased, and reversible/non-reversible blockages were improved. Besides, the use of UV irradiation during the washing of the membranes increased the FRR of the photocatalytic activated membranes to 91.2%. Compared to the bare PSf membrane in dye solution filtration, 1% Fe-doped ZnS QDs membrane yielded twice as much flux and 15% higher FRR results. Therefore, the results proved that metal-doped QDs can be used in the modification of PSf membranes with high efficiency.


Assuntos
Incrustação Biológica , Pontos Quânticos , Incrustação Biológica/prevenção & controle , Permeabilidade , Polímeros , Sulfetos , Sulfonas , Compostos de Zinco
12.
Clin Nutr ESPEN ; 45: 389-398, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34620345

RESUMO

BACKGROUND & AIMS: A sedentary lifestyle is one of the major health concerns of all societies that is associated by an increased risk of cardiovascular diseases. In this regard, we compared the anthropometric parameters, physical fitness (PF), lipid profile, and nutritional status of older adults with different levels of physical activity (PA). METHODS: In this cross sectional study, 220 older people (age: 67.39 ± 2.08 yrs) according to their PA levels had been categorized at high (n = 72), moderate (78) and low (n = 70) PA groups. The International Physical Activity Questionnaires and food frequency questionnaire has been used to determine the PA and nutritional status, respectively. Waist and hip circumference, height, weight, and body mass index of subjects were measured and calculated. Both lower and upper body strength, flexibility, static and dynamic balance, and endurance performance factors were used to determine the level of PF. To assess blood biochemical factors, subjects were asked to visit the laboratory after 12 h of fasting. RESULTS: The results showed waist circumference, hip circumference, and body fat percent were significantly lower in the high PA group compared to the low PA group in both males and females (P ≤ 0.05). Upper body strength, lower body strength, static balance, dynamic balance flexibility and endurance were significantly better in the high PA group compared to the low PA group in both males and females (P ≤ 0.05). Moreover, triglyceride was significantly lower in the high PA group compared to the low PA group in both males and females (P ≤ 0.05). According to the post hoc results, high-density lipoprotein, low-density lipoprotein and fasting glucose were significantly better in the high PA group compared to the low PA group in both males and females (P ≤ 0.05). All participants regardless PA levels showed insufficient consumption of zinc, calcium, vitamin E, and vitamin D (P ≤ 0.05). On the other hand, carbohydrate, sodium, iron, vitamin C and niacin intake significantly above recommended dietary allowance (P ≤ 0.05). CONCLUSIONS: The results of the current work showed that a higher level of PA improved anthropometric indicators, PF, and lipid profile in Iranian older adults. Moreover, older nutrition should be monitor to maintain their physical health and to prevent them from developing chronic diseases and their malnutrition complications.


Assuntos
Estado Nutricional , Aptidão Física , Idoso , Estudos Transversais , Exercício Físico , Feminino , Humanos , Irã (Geográfico) , Masculino
13.
Int J Biol Macromol ; 186: 1-12, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34242644

RESUMO

This work provides a new perception toward the application of the graphenic-biopolymeric composites as a solid-bed for separation and purification of bioactive compounds. Graphene oxide nanocomposites with functionalized sheets by soluble and insoluble nanocomplexes of chitosan and Arabic gum, were successfully synthesized and employed for the adsorption and purification of crocin, a nutraceutical from saffron. The composites exhibited a nanostructured scaffold with a particle size of 10 nm and experienced an unprecedented increase in the surface area by about 300% and improved d-spacing sheets by 17%. The optimum conditions for crocin separation were temperature = 318 K, stirring rate = 300 rpm, initial concentration = 100 mg L-1 and pH = 6. Under these conditions, the nanocomposites separated 99.1% of crocin in an equilibrium time of 30 min. The adsorption data were best represented by Freundlich isotherm and pseudo-second-order kinetic models. The thermodynamic studies indicated that the crocin adsorption on nanocomposites was an endothermic, spontaneous and physisorption process. The high-performance liquid chromatography (HPLC) analysis revealed that produced nanocomposites adsorbed crocin efficiently from saffron extract with a purity similar to the standard sample. The possible interaction mechanisms between crocin and nanocomposites were electrostatic interactions and hydrogen bonding.


Assuntos
Carotenoides/isolamento & purificação , Quitosana/química , Crocus/química , Grafite/química , Goma Arábica/química , Nanocompostos , Adsorção , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Ligação de Hidrogênio , Cinética , Nanotecnologia , Eletricidade Estática , Propriedades de Superfície
14.
Chemosphere ; 283: 131288, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34182650

RESUMO

Crude oil contaminated lands are recognised to have significant contributions to airborne volatile organic compounds (VOCs) with adverse effects on human health and tropospheric ozone. Soil capping systems for controlling harmful emissions are critical engineering solutions where advanced soil remediation techniques are neither available nor feasible. Studies on the adsorption of single VOC species in biochar have shown promising results as a potential capping material; however, current understanding of mixed gas system and multi-component adsorption of VOCs on biochar which would represent more realistic in situ conditions is very limited. We present, for the first time, the results of a study on competitive adsorption of mixed VOCs, including aromatic and non-aromatic VOCs commonly emitted from crude oil contaminated sites on two types of biochar pyrolysed at 500°C from wheat straw and bagasse as feedstock. The kinetics of sorption of multicomponent VOCs including acetone, hexane, toluene and p-xylene in biochar are studied based on the results of an extensive experimental investigation using a bespoke laboratory setup. Both biochar types used in this study presented a high sorption capacity for VOC compounds when tested individually (51-110 mg/g). For the multicomponent mixture, the competition for occupying sorption sites on biochar surface resulted in a lower absolute sorption capacity for each species, however, the overall sorption capacity of biochar remained more or less similar to that observed in the single gas experiments (50-109 mg/g). The chemical interactions via hydrogen bonds, electrostatic attraction, and pore-filling were found to be the main mechanisms of adsorption of VOC in the biochar studied. The efficiency of biochar regeneration was assessed through five cycles of adsorption-desorption tests and was found to be between 88% and 96%. The incomplete desorption observed confirm the formation of likely permanent bonds and heel build-ups during the sorption process.


Assuntos
Compostos Orgânicos Voláteis , Adsorção , Carvão Vegetal , Humanos , Tolueno
15.
Metab Brain Dis ; 36(8): 2263-2271, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34003412

RESUMO

Vascular endothelial growth factor (VEGF) regulates angio/neurogenesis and also tightly links to the pathogenesis of Alzheimer's disease (AD). Although exercise has a beneficial effect on neurovascular function and cognitive function, the direct effect of exercise on VEGF-related signaling and cognitive deficit in AD is incompletely understood. Therefore, the purpose of this study was to investigate the protective effect of exercise on angiostatin/VEGF cascade and cognitive function in AD model rats. Wistar male rats were randomly divided into five groups: control (CON), injection of DMSO (Sham-CON), CON-exercise (sham-EX), intrahippocampal injection of Aß (Aß), and Aß-exercise (Aß-EX). Rats in EX groups underwent treadmill exercise for 4 weeks, then the cognitive function was measured by the Morris Water Maze (MWM) test. mRNA levels of hypoxia-induced factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), vascular endothelial growth factor receptor 2 (VEGFR2), and angiostatin were determined in hippocampus by RT-PCR. We found that spatial learning and memory were impaired in Aß-injected rats, but exercise training improved it. Moreover, exercise training increased the reduced mRNA expression level of VEGF signaling, including HIF1α, VEGF, and VEGFR2 in the hippocampus from Aß-injected rats. Also, the mRNA expression level of angiostatin was elevated in the hippocampus from Aß-injected rats, and exercise training abrogated its expression. Our findings suggest that exercise training improves cognitive function in Aß-injected rats, possibly through enhancing VEGF signaling and reducing angiostatin.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/metabolismo , Doença de Alzheimer/terapia , Peptídeos beta-Amiloides/farmacologia , Angiostatinas/metabolismo , Angiostatinas/farmacologia , Animais , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/terapia , Modelos Animais de Doenças , Hipocampo/metabolismo , Masculino , Aprendizagem em Labirinto , Ratos , Ratos Wistar , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-33641093

RESUMO

In this study, we designed Fe3O4 nanoparticles and heterogeneous Fe3O4-Au nanocomposites with a mean size of 21 and 27 nm that synthesized by Foeniculum vulgare seed extract to photodegrade organic micropollutants under UV and visible light irradiation. The physiochemical characteristics of biogenic nanoparticles/nanocomposite are described by XRD, FTIR, UV-Vis, SEM, EDX, and X-ray elemental mapping. In the presence of nanoparticles and nanocomposites under UV irradiation, the total degradation of contaminants is about 85-90% after 2100 s, while under visible light irradiation, degradation efficiencies are about 70-85% after 4800-s irradiation. Total organic carbon analysis results confirmed photodegradation efficacies. Also, the scavenger's experiments show that hydroxyl radical is the most important specie in the degradation of pollutant model. It can be concluded clearly that Fe3O4 green nanoparticles and Fe3O4-Au green nanocomposite are very simple and effective photocatalyst for degradation of organic pollutants in very short time under illumination.

17.
Chemosphere ; 268: 129310, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33359840

RESUMO

Inland oil spillage is one of the widespread sources of crude oil volatile organic compound emissions (CVEs) for which the long-term remedial solutions are often complex and expensive. This paper investigates the potential of a low-cost containment solution for contaminated solids by volatile organic compounds (VOCs) using biochar. The results of an extensive experimental investigation are presented on the sorption kinetics of xylene isomers (one type of the most frequently detected CVEs) on commercial biochar produced by prevalent feedstocks (wheat, corn, rice and rape straw as well as hardwood) at affordable temperatures (300-500°C). Chemical and physical properties of biochar were analysed in terms of elemental composition, scanning electron microscopy, specific surface area, ATR-FTIR spectra and Raman spectrometry. We show that for high-temperature biochar with similar surface chemistry, the sorption efficiency is mainly controlled by porous structure and pore size distribution. Biochar samples with higher specific surface area and higher volume of mesopores showed the highest sorption capacity (45.37-50.88 mg/g) since the sorbate molecules have more access to active sites under a greater intra-particle diffusion and elevated pore-filling. P-xylene showed a slightly higher sorption affinity to biochar compared to other isomers, especially in mesoporous biochar, which can be related to its lower kinetic diameter and simpler molecular shape. The sorption capacity of biochar produced at higher pyrolysis temperatures was found to be more sensitive to changes in ambient temperature due to dominant physical adsorption. Elovich kinetic model was found to be the best model to describe xylenes' sorption on biochar which indirectly indicates π-π stacking and hydrogen bonding as the main mechanism of xylene sorption on these types of biochar.


Assuntos
Carvão Vegetal , Xilenos , Adsorção , Pirólise
18.
Artigo em Inglês | MEDLINE | ID: mdl-32742551

RESUMO

Radiometer gain is generally a nonstationary random process, even though it is assumed to be strictly or weakly stationary. Since the radiometer gain signal cannot be observed independently, analysis of its nonstationary properties would be challenging. However, using the time series of postgain voltages to form an ensemble set, the radiometer gain may be characterized via radiometer calibration. In this article, the ensemble detection algorithm is presented by which the unknown radiometer gain can be analytically characterized when it is following a Gaussian model (as a strictly stationary process) or a 1st order autoregressive, AR(1) model (as a weakly stationary process). In addition, in a particular radiometer calibration scheme, the nonstationary gain can also be represented as either Gaussian or AR(1) process, and parameters of such an equivalent gain model can be retrieved. However, unlike stationary or weakly stationary gain, retrieved parameters of the Gaussian and AR(1) processes, which describe the nonstationary gain, highly depend on the calibration setup and timings.

19.
PLoS One ; 15(8): e0237148, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32745152

RESUMO

The susceptibility to cardiovascular disease in offspring could be reduced prior to birth through maternal intervention, before and during pregnancy. We evaluated whether the initiation periods of maternal exercise in preconception and pregnancy periods induce beneficial effects in the adult male offspring. Thirty-two female rats were divided into control and exercise groups. The exercise groups involve exercise before pregnancy or the preconception periods, exercise during pregnancy, and exercise before and during pregnancy. The mothers in the exercise groups were run on the treadmill in different periods. Then the birth weight and weekly weight gain of male offspring were measured, and the blood and left ventricle tissue of samples were collected for analysis of the Sirtuin 6 (Sirt6) and insulin growth factor-2 (IGF-2) gene expression, serum levels of low-density lipoprotein (LDL), high-density lipoprotein (HDL), cholesterol (Cho), and triglycerides (TG). There was no significant difference in the birth weight of offspring groups (P = 0.246) while maternal HIIT only during pregnancy leads to reduce weekly weight gain of offspring. Our data showed that Sirt6 and IGF-2 gene expression was increased (P = 0.017) and decreased (P = 0.047) by maternal exercise prior to and during pregnancy, respectively. Also, the serum level of LDL (p = 0.002) and Cho (P = 0.007) were significantly decreased and maternal exercise leads to improves the running speed of the adult male offspring (p = 0.0176). This study suggests that maternal HIIT prior to and during pregnancy have positive intergenerational consequence in the health and physical readiness of offspring.


Assuntos
Metabolismo dos Lipídeos , Miocárdio/metabolismo , Condicionamento Físico Animal/métodos , Sirtuínas/genética , Animais , Peso ao Nascer , Doenças Cardiovasculares/prevenção & controle , Colesterol/sangue , Feminino , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/metabolismo , Lipoproteínas LDL/sangue , Masculino , Gravidez , Ratos , Ratos Wistar , Sirtuínas/metabolismo , Triglicerídeos/sangue
20.
J Neuroimmunol ; 346: 577306, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32629305

RESUMO

Exercise has been shown to increase myelin biomarkers such as klotho and PLP and improve clinical and pathological symptoms using the experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis (MS). In the present study, we evaluated whether 6 weeks of high-intensity interval training (HIIT) prior to induction of EAE increase klotho and/or PLP and attenuate the severity of symptoms and/or disease progression in EAE model. Our data demonstrate that HIIT increased klotho and PLP and decreased disability. These proteins are associated with maintaining myelination and further research is required to examine potential clinical relevance.

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