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1.
Heliyon ; 10(6): e27701, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38515659

RESUMO

Countries face exasperating and inclement climate worldwide. Food and feed security could be their paramount life objective. The study aimed to investigate the impact of selenium on the protein content and distribution in different parts of rice. For this purpose, advanced selenium biofortified breeding material developed after generations of breeding efforts was investigated at the field area, rice research institute, Chengdu, China during cropping season 2021-22. The accumulation and distribution of selenium and protein contents were observed in various fractions of selenium-enriched rice (Z3057B) and positive control (727). The correlation studies for selenium and protein quantification leads to the optimization of the breeding material and relevance in virtue. The rice fractions indicated rice embryo retains highest selenium contents, which gradually decreases in succession (other rice parts). The difference in protein content between the embryo and endosperm of Se-enriched rice is significant, while that between embryo and aleurone layer is not obvious. The selenium protein was found with molecular weight of 13.6-122.6 kDa. The protein of each molecular weight is found to bind with selenium, but the binding strength of selenium is negatively correlated with the molecular weight of protein. The 67.5% of the total selenium sticks with protein having molecular weight less than 38.8 kDa. In summary, protein with low molecular weight (13.4 kDa) binds maximum selenium and accounts for highest total protein content (40.76%).

2.
Reprod Domest Anim ; 59(3): e14551, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38462999

RESUMO

Cryopreservation is one of the reliable techniques for long-term storage of sperm. The success of this technique depends on the choice of cryoprotectant; therefore, a plethora of literature has reported the effects of different cryoprotective agents so far. Kappa-carrageenan (κ-carrageenan) is a hydrocolloid polysaccharide extracted from red marine seaweed. Its unique property makes it a promising option as a non-colligative cryoprotectant. The current study aims to evaluate the cryoprotective effect of k-carrageenan along with glycerol on ram sperm quality both after equilibration and freezing. Nine Kajli rams were utilized in this experiment for semen collection through an artificial vagina maintained at 42°C. Qualified samples were diluted in tris egg yolk glycerol (TEYG) extender containing different concentrations of k-carrageenan as 0 mg/mL (control), 0.2, 0.5, 0.8 and 1 mg/mL. Post-thaw assessment was done at 37°C after 24 h of storage, which showed a significant improvement (p < .05) in sperm viability, motility, membrane and acrosome integrity in an extender containing k-carrageenan at a concentration of 0.5 mg/mL compared to control. It is concluded from the current study that the combination of glycerol and 0.5 mg/mL concentration of k-carrageenan improved the sperm post-thaw quality.


Assuntos
Preservação do Sêmen , Sêmen , Masculino , Ovinos , Animais , Carragenina/farmacologia , Glicerol/farmacologia , Motilidade dos Espermatozoides , Espermatozoides , Crioprotetores/farmacologia , Criopreservação/veterinária , Criopreservação/métodos , Carneiro Doméstico , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Suplementos Nutricionais
3.
Sci Rep ; 13(1): 22465, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38105310

RESUMO

Safety at the gore areas near diverging ramps is very crucial during planning and implementation of highway safety improvement programs. Limited research has been conducted on safety at the gore areas on arterial roads. This study aims at investigating the impact of improving a sharp gore area in Lincoln, Nebraska by performing a micro simulation before-and-after study with respect to its underlying state of safety and congestion. Data on travel times and traffic volumes for peak hours are incorporated after successful calibration to find out how a geometric intervention can decrease mobility issues as well as the likelihood of crash involvement. This study has utilized VISSIM software package to run the simulation however, to perform safety analysis, Surrogate Safety Assessment Model (SSAM) is used which is developed by the Federal Highway Administration (FHWA). During the model calibration, custom driving behaviors are created to represent driving tendencies of familiar drivers. The simulation results indicated that by adding an auxiliary lane near the gore area, the mobility issues such as bottle necks, lane changing dilemmas and queue lengths are substantially decreased. However, geometric interventions such as provision of a separate lane, increasing ramp spacing, nose spacing, deceleration area and queue storage area considerably reduced the likelihood of rear-end and lane changing crashes. Surrogate safety assessment in diverging ramps, particularly for sharp gores, has not previously been studied, and this study can serve as a primary footmark for future research on ramp-gores safety.

4.
Materials (Basel) ; 15(9)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35591556

RESUMO

In the past, many studies have been conducted on the optimization of reinforced concrete (RC) structures. These studies have demonstrated the effectiveness of different optimization techniques to obtain an economical design. However, the use of optimization techniques to an obtain economical design is not so practical due to the difficulty in applying most of the optimization techniques to achieve an optimal solution. The RC beam is one of the most common structural elements encountered by a practising design engineer. The current study is designed to highlight the potential of the Solver tool in MS Excel as an easy-to-use option for optimizing the design of simply supported RC beams. A user-friendly interface was developed in a spreadsheet in which beam design parameters from a typical design can be entered and an economical design can be obtained using the Evolutionary Algorithm available in the MS Excel Solver tool. To demonstrate the effectiveness of the developed optimization tool, three examples obtained from the literature have been optimized. The results showed that up to 24% economical solution can be obtained by keeping the same material strengths that were assumed in the original design. However, if material strength is also considered as a variable, up to 44% of the economical solution can be obtained. A parametric study was also conducted to investigate the effect of different design variables on the economical design of simply supported RC beams and to derive useful rules of thumb for their design and proportioning, with the objective of cost minimization. The results of the parametric study suggest that the grade of the reinforcing steel is one of the most influential factors that affect the cost of simply supported RC beams. Practicing engineers can use the trends derived from this research to further refine their optimal designs.

5.
Sci Rep ; 12(1): 2493, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35169158

RESUMO

In the present work, nonwoven cotton fabric was modified for antibacterial applications using low-cost and eco-friendly precursors. The treatment of fabric with alkali leads to the formation of active sites for surface modification, followed by dip coating with silver nanoparticles and chitosan. The surface was chlorinated in the next step to transform amide (N-H) groups in chitosan into N-halamine (N-Cl). The modified and unmodified surfaces of the nonwoven cotton fabric have been characterized by FTIR, SEM, and XRD. The active chlorine loading is measured with iodine/sodium thiosulphate. The antimicrobial activity and cell toxicity assay were carried out with and without modifications of nonwoven cotton fabric. The antimicrobial efficacies of loaded fabric were evaluated against four bacterial species (Micrococcus luteus, Staphylococcus aureus, Enterobacter aerogenes, and E.coli). It was found that modified fabric exhibited superior efficiency against gram-positive and gram-negative bacterial strains as compared to their bulk counterparts upon exposure without affecting strength and integrity of fabric. The overall process is economical for commercial purposes. The modified fabric can be used for antimicrobial, health, and food packaging industries, and in other biomedical applications.

6.
Chemosphere ; 293: 133537, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35016954

RESUMO

The precise detection of hazardous 2,4,6-Trinitrophenol (TNP) is essential for the environment and human health. TNP is used as a precursor in whistling fireworks in ammunition, mining, agriculture and is a hazardous environmental pollutant generated from leather, chemical, and dye industries. Exploring rapid and low-cost approaches for the detection and quantification of TNP has attracted many scientists nowadays. The proposed chemosensor utilizes the concept of dispersive liquid-liquid micro-extraction coupled with a UV-visible spectrophotometer for its sensing at the ultra-trace level. Significant changes based on intramolecular interactions followed by a distinct color change to orange-red from yellow in the presence of TNP is an attractive feature for the present study. The successive addition of TNP shows ultra-trace sensitivity (3.9831 µA µM-1 cm-1) at detection limit (LOD) of 0.0015 ± 0.03 µM (S/N = 3), a linear range of 0 µM-70 µM, and a response time of <5 min. Different types of real samples such as creatinine testing kit reagent, fireflies crackers, serum, and water samples were used and recovery of TNP was calculated by spiking the known concentration of the standard analyte. The obtained recovery was 93.6-103.6% with RSD range of 1.6-4.53% (n = 3) in different samples. The analytical performance of the colorimetric Chemoprobe in terms of its recovery, linearity range, and limit of detection offers an excellent platform for monitoring hazardous TNP. The results show that the proposed colorimetric chemosensor is easy to use, low-cost, environmentally friendly and offers an easily observable visual color change. Based on these features, the chemosensor can be used for large-scale applications for the detection of TNP in water and other samples.


Assuntos
Colorimetria , Águas Residuárias , Aminas , Corantes Fluorescentes/química , Humanos , Picratos
7.
Plant Physiol Biochem ; 170: 1-13, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34839203

RESUMO

Selenium (Se) is a beneficial element, but only when present within its permissible range. Its hyper-accumulation in edible plant parts can cause Se toxicity. This study aimed to develop an agronomic plan for biofortification of rice with Se and reclamation of cadmium (Cd)-contaminated soil, utilizing sodium selenite (Na2SeO3) and cadmium chloride (CdCl2) as soil treatments. Biofortification was performed on two target rice varieties: genotypes 5097A/R2035 and GangYou725, in field trials by applying Cd at a concentration of 0-8 mg kg soil-1 and Se at 0-1 mg kg soil-1. Since these rice varieties have different metabolic specificity, the degree of elemental accumulation, deviations in chlorophyll concentration, activity of photosynthetic apparatus and grain yield were assessed. It was found that application of 1 mg kg-1 Se2O3 decrease Cd content and increased chlorophyll content and photosynthetic activity while grain yield was unaffected by application of the metallic trace-elements. Comparing effects at different stages, we found that the 50% heading stage was most sensitive to metal application. In sum, Se mitigates Cd toxicity, but hyperaccumulation of Se (4 mg kg-1) in polished rice was observed with Cd at 4 and 8 mg kg-1. The elevated level of Cd stress in pot experiments resulted in over-accumulation of Se in the germ and endosperm that poses serious health concerns.


Assuntos
Oryza , Selênio , Poluentes do Solo , Cádmio/análise , Cádmio/toxicidade , Selênio/farmacologia , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
8.
Diagnostics (Basel) ; 11(6)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073620

RESUMO

Cerebral venous sinus thrombosis (CVST) is a rare cause of stroke that accounts for 0.5-1.0% of all strokes. Clinical presentation, predisposing factors, neuroimaging findings, and outcomes of CVST are extremely diverse, which causes a high index of suspicion in diagnosis. Therefore, early diagnosis of CVST is crucial for prompt treatment to prevent morbidity and mortality. OBJECTIVE: The purpose of this prospective study is aimed at assessing the clinical characteristics, potential risk factors, and neuro-radiological features along with the topography of venous sinus involved in CVST patients in a tertiary care hospital, Lahore, Pakistan. MATERIAL AND METHODS: Consecutive patients enrolled in this study had a computed tomography (CT) scan, magnetic resonance imaging (MRI), and magnetic resonance venography (MRV) along with a clinical presentation to confirm the diagnosis of CVST. Categorical data were presented as percentages. Continuous variable and categorical data were compared (parenchymal lesions vs. non-parenchymal lesions) using the Student's t-test and Chi-square test, respectively. RESULTS: A total of 3261 patients with stroke were presented during the study period. Out of all patients, 53 confirmed patients with CVST (1.6%) were recruited; the predominant population was female (84.91%), having a male to female ratio of 1:4. Mean age of the cohort was 28.39 ± 7.19 years. Most frequent symptoms observed were headache (92.45%) followed by vomiting (75.47%), seizures (62.26%), papilledema (54.72%), visual impairment (41.51%), and altered consciousness disturbance (52.83%). The presumed risk factors associated with CVST were puerperium (52.83%), use of oral contraceptives (13.21%), antiphospholipid syndrome (7.55%), elevated serum levels of protein C and S (5.66%), and CNS infection (3.77%). On cranial CT scans, 50 patients (94.33%) showed abnormalities while 32 patients exhibited various parenchymal lesions. Seizures were more frequent in CVST patients with parenchymal lesions compared with subjects lacking parenchymal lesions. Seventy-two sinuses, either single or in combination, were involved in CVST patients, being more common in patients with parenchymal lesions than those without parenchymal lesions. The most frequent locations of CVST were the superior sagittal and transverse sinus. CONCLUSION: In short, non-contrast CT brain may be used as a first line investigation in suspected cases of CVST. Our study also demonstrates some regional differences in the clinical features, risk factors, and neuroimaging details of CVST as described by some other studies. Therefore, care must be taken while diagnosing and predicting the outcome of the CVST.

10.
Environ Sci Pollut Res Int ; 28(16): 20023-20033, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33409993

RESUMO

Cadmium (Cd) is an element injurious for human health and is possibly toxic to organisms at minor concentrations. While some of other trace metallic elements have antagonistic features to it. One of them is the interaction between selenium (Se) and Cd in plant different organs. Literature review disclosed that the intake of Se to some extent can reduce the accumulation of Cd in plants, while the research on of trace metallic elements (Cd) and Se-enriched food (rice) in the living body has rarely been reported. This study intended to explore whether there was a mitigating effect of Se-enriched rice on mice poisoned with Cd. A mouse model of low-dose and high-dose Cd poisoning was established (supplemented with cadmium chloride(CdCl2·2½H20)), followed by feeding two groups (1) Se-enriched rice and (2) setting an equal amount of inorganic Se group. After that, the impact of Se-enriched rice on the antioxidant activity was evaluated. The Se-enriched diet enhanced the total antioxidant capacity (T-AOC), superoxide dismutase (SOD), and enzyme activities of GSH peroxidase (GSH-Px) in mice livers and kidney whereas significantly decreased the malondialdehyde (MDA) contents. Moreover, the degree of physiological damage in mice with low cadmium poisoning was significantly alleviated, and the expression of antioxidant genes (Nrf-2, GPX1, TrxR2, TNF-2) was increased. In conclusion, the Se-enriched diet has a positive effect on the biological effects in mice, and it can be used as a daily diet to resist damage to the body's low Cd state and support enzymatic antioxidant systems by eliminating oxidative injury.


Assuntos
Intoxicação por Cádmio , Oryza , Selênio , Animais , Antioxidantes , Cádmio , Camundongos
11.
Environ Sci Pollut Res Int ; 27(14): 16940-16949, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32144709

RESUMO

Selenium (Se) is an essential micronutrient and important component of oxidase which protects cell membranes, eliminate the role of free radicals in the human body. Se is necessary for low Se rice genotypes and Se deficient areas. Zinc (Zn) is a micro-battalion that affects the growth, development, aging, drought resistance, disease resistance, and many other aspects for rice. The effects of Se and Zn fertilization on Se and Zn concentrations were evaluated including the response of superoxide dismutase (SOD), catalase (CAT) enzymes activity, and grain yield under single Se, Zn, and combined Se-Zn application using R725 rice variety in pot experiment with 8 treatments (0, Zn5, Zn10, Zn15, Se1, Zn5 + Se1, Zn10 + Se1, and Zn15 + Se1) mg/kg of soil and three replications. Moreover, germination% and seedling growth of resulted seeds from this experiment were evaluated for the agronomical benefit of farmers. The results revealed that Se and Zn had a cumulative effect on each other, but more Se increase was activated than Zn under the combined Se-Zn application. Zinc application had the small effect on Zn concentration in the different fractions but the positive effect on carotenoids and the yield (both applied alone and in combination with Se). Single Se application resulted in a positive effect on Zn accumulation in grain and husk with the high effectiveness of Se accumulation and loss during processing. Combined Se-Zn application had positive effect on carotenoids, CAT, grain yield, and total dry matter. Moreover, single Zn and combined Se-Zn application had a positive effect on germination% and seedling growth. Agronomic biofortification with combined Se-Zn supply provided both agronomic and nutritional benefits for rice in the current pot trail. However, as Se preferably accumulated in the edible part as compared to Zn, 1 mg Se/kg fertilization was unsafe for edible purposes according to the national standard of China (0.04-0.3 mg/kg) but could be recommended as medicine.


Assuntos
Oryza , Selênio/análise , China , Grão Comestível/química , Humanos , Plântula/química , Zinco/análise
12.
J Ayub Med Coll Abbottabad ; 32(Suppl 1)(4): S686-S690, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33754532

RESUMO

BACKGROUND: The purpose of this study was to estimate the effect of social distancing (days since the imposition of a lock-down) and the number of daily tests conducted per million population on the daily growth rate of COVID-19 cases. METHODS: After excluding the first 30 days since the announcement of an index case in a country, relevant data for the next forty days was collected from four countries: Belgium, Italy, South Korea and United Kingdom. Two online databases: Our World in Data and worldometer were used for the collection of data which included the number of new COVID-19 cases and the number of tests conducted on a given day. The acquired figures were transformed into per million population of the given country. The growth rate of daily COVID-19 cases was derived and was used as the regress and in a multiple linear regression with the number of tests per million population per day and the number of days since a lock-down was imposed as the regressors. RESULTS: It was found that the growth rate of daily COVID-19 cases decreased by .051% when the number of daily tests conducted per million population increased by 1. A .532% decrease in the growth rate of daily COVID-19 cases was observed with each passing day of a lock-down, which essentially represented the most effective form of social distancing. A significant regression was calculated (F (2, 155) = 35.191, p=.014), with an R2 of .054. Neither the daily number of tests conducted per million population nor the number of days of maintaining social distancing (lock-down) was individually significant contributors to the prediction of the growth rate of daily COVID-19 cases (p=.267 and p=.554 respectively). CONCLUSION: An extensive and rapid increase in the daily number of testing capacity and maintaining social distancing can decrease the growth rate of daily COVID-19 cases. Depending on the availability of the required resources, timely implementation of these measures can lead to better outcomes for a given population.


Assuntos
COVID-19/epidemiologia , Controle de Doenças Transmissíveis/métodos , Transmissão de Doença Infecciosa/prevenção & controle , Pandemias , Distanciamento Físico , Bélgica/epidemiologia , COVID-19/transmissão , Feminino , Humanos , Incidência , Itália/epidemiologia , Masculino , República da Coreia/epidemiologia , SARS-CoV-2 , Reino Unido/epidemiologia
13.
J Ayub Med Coll Abbottabad ; 32(Suppl 1)(4): S691-S694, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33754533

RESUMO

BACKGROUND: Corona virus disease 2019 (COVID-19) is a pandemic affecting over 150 million people worldwide since its emergence in Wuhan, China in December 2019, and is leading to over 600 thousand deaths. Severe acute respiratory syndrome novel coronavirus 2 (SARS-nCoV-2) causes a wide range of symptoms by affecting different organ systems of the body. This study was designed to specifically look for its rheumatological manifestations. METHODS: It was a cross-sectional study conducted in the corona complex MTI Lady Reading Hospital Peshawar. A total of 141 COVID-19 positive hospitalized patients requiring oxygen therapy and having no previous rheumatological diseases were enrolled and studied for any rheumatological manifestations. RESULTS: There were 88 (62.4%) males and 53 (37.6%) females, with age range from 27-88 years, and mean age of 58.5±11.5 SD. Arthralgia and myalgia were found very common, occurring in 128 (90.8%) and 119 (84.4%) of patients. Arthritis was not found in any patient. CONCLUSION: Arthralgia and myalgia were reported frequently in patients with severe COVID-19 requiring oxygen therapy, while arthritis was not present even in a single patient as is reported in other viral infections.


Assuntos
COVID-19/epidemiologia , Pandemias , Doenças Reumáticas/epidemiologia , Atenção Terciária à Saúde , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Doenças Reumáticas/terapia , SARS-CoV-2 , Adulto Jovem
14.
Biol Trace Elem Res ; 196(1): 119-130, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31786753

RESUMO

Ageing is an irreversible phenomenon and the processes which can delay it are under consideration for a long time by the scientific community. Selenium is an important candidate for it, but the impact of selenoprotein on nutritional changes and ageing has not been reported well. In this regard, antioxidant activities and free radical scavenging effect of selenoproteins extracted from selenium-rich rice were studied. Mice were administered a subcutaneous abdominal injection of D-galactose to induce the ageing model and fed with different selenoprotein dosage diet. Deviations among biochemical activities (total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and malondialdehyde (MDA)) in liver and serum of the mice were assessed. The degree of liver injury, antioxidant genes and protein relative expression were estimated. The protein content, selenium content, hydroxyl scavenging and DPPH radicals were accessed in selenoprotein components. The selenoprotein constituent had protein and selenium contents in different components as water-soluble proteins > alkali-soluble proteins > salt-soluble proteins > ethanol-soluble proteins. The enzymatic activity (total antioxidant capacity, GSH-Px and SOD) in liver and serum of mice was significantly enhanced in selenoprotein diet groups. D-Galactose-induced liver injury was significantly reduced by selenoprotein diet of 25 µg/(kg day). Real-time qPCR and Western blot disclosed the enhanced relative expression of antioxidant genes (SOD2, GPX1, TrxR2 and Nrf2) and HO-1 protein in the positive control (Vc) and selenoprotein diet groups. In conclusion, selenoprotein treatment was found to have a positive influence on liver hepatocytes and biochemical features in mice. It might be used as a potential diet in scavenging oxidative injury and supporting enzymatic antioxidant system.


Assuntos
Envelhecimento/efeitos dos fármacos , Antioxidantes/farmacologia , Oryza/química , Extratos Vegetais/farmacologia , Selênio/farmacologia , Selenoproteínas/química , Administração Oral , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Compostos de Bifenilo/análise , Compostos de Bifenilo/antagonistas & inibidores , Galactose/administração & dosagem , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos , Picratos/análise , Picratos/antagonistas & inibidores , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Selênio/administração & dosagem , Selenoproteínas/administração & dosagem
15.
BMC Plant Biol ; 19(1): 559, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31847801

RESUMO

BACKGROUND: The element selenium (Se) deficiency is thought to be a global human health problem, which could disperse by daily-supplement from Se-rich food. Increasing the accumulation of Se in rice grain is an approach matched to these nutrient demands. Nonetheless, Se is shown to be essential but also toxic to plants, with a narrow margin between deficiency and toxicity. Notably, the regulatory mechanism balancing the accumulation and tolerance of Se in Se-rich rice plants remains unknown. RESULTS: In this study, we investigated the phenotypical, physiological, and biochemical alterations of Se-rich rice in the exposure to a variety of Se applications. Results showed that the Se-rich rice was able to accumulate more abundance of Se from the root under a low Se environment comparing to the Se-free rice. Besides, excessive Se led to phytotoxic effects on Se-rich rice plants by inducing chlorosis and dwarfness, decreasing the contents of antioxidant, and exacerbating oxidative stresses. Furthermore, both phosphate transporter OsPT2 and sulfate transporters OsSultr1;2 may contribute to the uptake of selenate in rice. CONCLUSIONS: Se-rich red rice is more sensitive to exogenous application of Se, while and the most effective application of Se in roots of Se-rich rice was reached in 20 µM. Our findings present a direct way to evaluate the toxic effects of Se-rich rice in the Se contaminated field. Conclusively, some long-term field trial strategies are suggested to be included in the evaluation of risks and benefits within various field managements.


Assuntos
Oryza/metabolismo , Selênio/metabolismo , Solo/química , Bioacumulação , Selênio/administração & dosagem
16.
Materials (Basel) ; 12(17)2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31443524

RESUMO

Liquid exfoliated molybdenum disulfide (MoS2) nanosheets and polyaniline (PANI) nanoparticles are dispersed in polystyrene (PS) matrix to fabricate hybrid polymer composites with high dielectric and electromagnetic interference (EMI) shielding behavior. A phase-separated morphology is formed when PANI and MoS2 are incorporated into polystyrene (PS) matrix. An increasing concentration of MoS2 nanoparticles inside PS/PANI (5 wt %) polymer blend forms an interconnected network, resulting in high electrical conductivity and dielectric behavior, making them a suitable candidate for EMI shielding application. An increment in dielectric constant and loss, up to four and five orders of magnitude, respectively, is recorded at a maximum concentration of 1 wt % of MoS2 in PS/PANI-5 polymer blend at 100 Hz. The enhanced dielectric characteristics for PS/PANI/MoS2 composites are then theoretically evaluated for the estimation of EMI shielding effectiveness in the frequency range of 100 Hz to 5 MHz. The maximum dielectric constant and loss achieved for PS/PANI-5 wt %/MoS2-1 wt % are responsible for estimated shielding effectiveness of around 92 dB at 100 Hz. The increase in dielectric behavior and shielding effectiveness is probably due to the increased number of charged dipoles accumulated at the insulator-conductor interface.

17.
Biomolecules ; 9(6)2019 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31238551

RESUMO

Cadmium (Cd) is a well-known metal imposing threats to human health, and it can be accumulated in polished rice over the permitted range of 0.2 mg kg-1 (GB 2762-2017). It has been reported that selenium (Se) application decreases Cd uptake. Se-rich diets have gained attention recently, but the potential of Se-rich rice in mitigating Cd stress needs further investigation. In this study, a pot experiment in the field was conducted to assess the influence of environmental factors and exogenous split application of Se on the nutritional status of rice under Cd stress. The results indicated that the increased fertilizer treatment in soil bulk linearly increased the metal content in rice grains. Approximately 50-70% of metal was recovered in rice tissues, while 5-20% of the metal that was applied leached down into the soil. A Se concentration of 0.4 mg kg-1 could significantly improve the total Se content in grain and mitigate Cd toxicity (1 mg kg-1) below the permitted range. Panicles and roots were more active for total Se accumulation in Se-rich and non-Se-rich rice, respectively. Polishing and milling operations can significantly reduce the Cd content, as rice bran in rice tissues accumulated most of the metal's residues. The late matured rice cultivars consumed more heat units, and more metal contents were found in them. Collectively, it was found that Se can mitigate Cd toxicity, but the rice cultivation at T2 (high Cd; 2 mg kg-1 and Se; 1 mg kg-1) increased the metal uptake capability and health-risk index in polished rice, with its Se content heightened over permitted range of 0.04 to 0.30 mg kg-1 (GB/T 22499-2008). However, further molecular studies are required, in order to completely access the inverted Se accumulation behavior in rice tissues at high Cd soil stress.


Assuntos
Cádmio/toxicidade , Oryza/efeitos dos fármacos , Oryza/metabolismo , Selênio/metabolismo , Poluentes do Solo/toxicidade , Estresse Fisiológico/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Fertilizantes , Temperatura Alta , Estado Nutricional , Oryza/fisiologia , Risco
18.
Environ Sci Pollut Res Int ; 26(22): 22421-22430, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31154647

RESUMO

The synergistic effects of trace elements selenium (Se) and cadmium (Cd) are well known. But the reasons for the trending accumulation behavior in both trace elements are under debate in the scientific community. The present investigation was conducted to evaluate the impact of heat units on the accumulation behavior in two environments. Se and Cd were applied in three groups (T0; 0:0, T1; 0.4:1, T2; 1:2) mg kg-1. As the time of planting and heat units consumed by the crop to attain its physiological maturity appears to be different. The sunlight may contribute as an important manipulating factor for the accumulation of heavy metals in the plant. The results of the present study indicated that the behavior in the accumulation pattern of both elements appears to be distinct in the same material. The increased fertilizer treatment in soil bulk linearly increased the metal contents in rice grain. The studies between different plant parts disclosed panicle as the primary reservoir for Se and Cd accumulation. The plant sown earlier accumulates more Se than Cd while the plants uptake more Cd when sown 1 month later. The plant completes the critical developmental phases (tillering, heading, and flowering) within 20-30 days interval depending on the variety. But the late-sown plants complete these transitional phases within 9-10 days interval ultimately result in less utilization of heat units. These quick transitional changes may lead to the uptake of an ample amount of Cd contents in rice grain even at a low level of Cd stress (1 and 2 mg kg-1), making rice unsafe for edible purposes. The proper time of planting could be effective in timely acclimatization of Se and Cd sequestration and translocation in rice various components. Graphical Abstract.


Assuntos
Cádmio/análise , Grão Comestível/química , Fertilizantes/análise , Metais Pesados/análise , Oryza/efeitos dos fármacos , Selênio/análise , Transporte Biológico , Metais Pesados/química , Oryza/química , Selênio/química , Solo
19.
Environ Sci Pollut Res Int ; 26(17): 17834-17844, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31037530

RESUMO

Selenium (Se) is a vital element which leads to strong antioxidation in animals and humans. However, the mechanism underlying natural cereal Se-induced biological changes is not well understood. This study intended to explore the gene differential expression in naturally aged mice exposed to selenium by RNA-Seq technique. A total spectrum of 53 differentially expressed genes was quantified in mice heart tissues treated with Se-rich and general rice. The GO functional annotation of differentially expressed genes disclosed the enrichment of cellular process, ionic binding, biological regulation, and catalytic activity. One hundred twenty-three differential pathways (cardiovascular diseases, immune system, transport and catabolism, longevity regulating, and PI3K-AKT signaling) were identified according to KEGG metabolic terms. Afterwards, the effect of Se-rich rice on the antioxidant activity was assessed. The selenium-rich diet increased the total antioxidant capacity (T-AOC), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) in mice serum and livers while significantly reduces methane dicarboxylic aldehyde (MDA) contents. FOXO1 and FOXO3 genes, which acted as the regulators of apoptosis and the antioxidant enzyme, were significantly enhanced in mice when fed with Se-rich rice. In short, the present findings disclosed the alluring insights of organic and inorganic selenium sources on certain biological processes and antioxidant activity of living bodies. However, long-term trials are still required to draw a definitive conclusion, including risks and benefit analysis for various management strategies.


Assuntos
Antioxidantes/metabolismo , Oryza/metabolismo , Selênio/metabolismo , Animais , Glutationa Peroxidase/metabolismo , Fígado/metabolismo , Camundongos , Oryza/química , Fosfatidilinositol 3-Quinases/metabolismo , Selênio/análise , Superóxido Dismutase/metabolismo , Transcriptoma/efeitos dos fármacos
20.
Biomolecules ; 9(4)2019 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-30935009

RESUMO

This work was designated to scrutinize the protein differential expression in natural selenium-enriched and non-selenium-enriched rice using the Isobaric-tags for relative and absolute quantification (iTRAQ) proteomics approach. The extracted proteins were subjected to enzyme digestion, desalting, and identified by iTRAQ coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) technology. High pH C18 separation analysis was performed, and the data were then analyzed by Protein PilotTM (V4.5) search engine. Protein differential expression was searched out by comparing relatively quantified proteins. The analysis was conducted using gene ontology (GO), cluster of orthologous groups of proteins (COG) and Kyoto encyclopedia of genes and genomes (KEGG) metabolic pathways. A total of 3235 proteins were detected and 3161 proteins were quantified, of which 401 were differential proteins. 208 down-regulated and 193 up-regulated proteins were unveiled. 77 targeted significant differentially expressed proteins were screened out for further analysis, and were classified into 10 categories: oxidoreductases, transferases, isomerases, heat shock proteins, lyases, hydrolases, ligases, synthetases, tubulin, and actin. The results indicated that the anti-stress, anti-oxidation, active oxygen metabolism, carbohydrate and amino acid metabolism of natural selenium-enriched rice was higher than that of non-selenium rice. The activation of the starch synthesis pathway was found to be bounteous in non-selenium-enriched rice. Cysteine synthase (CYS) and methyltransferase (metE) might be the two key proteins that cause amino acid differences. OsAPx02, CatC, riPHGPX, HSP70 and HSP90 might be the key enzymes regulating antioxidant and anti-stress effect differences in two types of rice. This study provides basic information about deviations in protein mechanism and secondary metabolites in selenium-enriched and non-selenium-enriched rice.


Assuntos
Oryza/efeitos dos fármacos , Proteínas de Plantas/genética , Proteômica , Selênio/farmacologia , Cromatografia Líquida , Biologia Computacional , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Oryza/metabolismo , Proteínas de Plantas/análise , Proteínas de Plantas/metabolismo , Espectrometria de Massas em Tandem
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