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1.
Neuroscience ; 542: 59-68, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38369007

RESUMO

Brain Computer Interface (BCI) is a highly promising human-computer interaction method that can utilize brain signals to control external devices. BCI based on functional near-infrared spectroscopy (fNIRS) is considered a relatively new and promising paradigm. fNIRS is a technique of measuring functional changes in cerebral hemodynamics. It detects changes in the hemodynamic activity of the cerebral cortex by measuring oxyhemoglobin and deoxyhemoglobin (HbR) concentrations and inversely predicts the neural activity of the brain. At the present time, Deep learning (DL) methods have not been widely used in fNIRS decoding, and there are fewer studies considering both spatial and temporal dimensions for fNIRS classification. To solve these problems, we proposed an end-to-end hybrid neural network for feature extraction of fNIRS. The method utilizes a spatial-temporal convolutional layer for automatic extraction of temporally valid information and uses a spatial attention mechanism to extract spatially localized information. A temporal convolutional network (TCN) is used to further utilize the temporal information of fNIRS before the fully connected layer. We validated our approach on a publicly available dataset including 29 subjects, including left-hand and right-hand motor imagery (MI), mental arithmetic (MA), and a baseline task. The results show that the method has few training parameters and high accuracy, providing a meaningful reference for BCI development.


Assuntos
Interfaces Cérebro-Computador , Espectroscopia de Luz Próxima ao Infravermelho , Humanos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Redes Neurais de Computação , Algoritmos , Córtex Cerebral/diagnóstico por imagem , Mãos , Eletroencefalografia/métodos , Imaginação
2.
Med Biol Eng Comput ; 62(1): 107-120, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37728715

RESUMO

Motor imagery (MI) electroencephalogram (EEG) signal is recognized as a promising paradigm for brain-computer interface (BCI) systems and has been extensively employed in various BCI applications, including assisting disabled individuals, controlling devices and environments, and enhancing human capabilities. The high-performance decoding capability of MI-EEG signals is a key issue that impacts the development of the industry. However, decoding MI-EEG signals is challenging due to the low signal-to-noise ratio and inter-subject variability. In response to the aforementioned core problems, this paper proposes a novel end-to-end network, a fusion multi-branch 1D convolutional neural network (EEG-FMCNN), to decode MI-EEG signals without pre-processing. The utilization of multi-branch 1D convolution not only exhibits a certain level of noise tolerance but also addresses the issue of inter-subject variability to some extent. This is attributed to the ability of multi-branch architectures to capture information from different frequency bands, enabling the establishment of optimal convolutional scales and depths. Furthermore, we incorporate 1D squeeze-and-excitation (SE) blocks and shortcut connections at appropriate locations to further enhance the generalization and robustness of the network. In the BCI Competition IV-2a dataset, our proposed model has obtained good experimental results, achieving accuracies of 78.82% and 68.41% for subject-dependent and subject-independent modes, respectively. In addition, extensive ablative experiments and fine-tuning experiments were conducted, resulting in a notable 7% improvement in the average performance of the network, which holds significant implications for the generalization and application of the network.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia , Humanos , Imagens, Psicoterapia , Redes Neurais de Computação , Razão Sinal-Ruído , Imaginação , Algoritmos
3.
Brain Res ; 1823: 148673, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-37956749

RESUMO

Brain-computer interface (BCI) enables the control of external devices using signals from the brain, offering immense potential in assisting individuals with neuromuscular disabilities. Among the different paradigms of BCI systems, the motor imagery (MI) based electroencephalogram (EEG) signal is widely recognized as exceptionally promising. Deep learning (DL) has found extensive applications in the processing of MI signals, wherein convolutional neural networks (CNN) have demonstrated superior performance compared to conventional machine learning (ML) approaches. Nevertheless, challenges related to subject independence and subject dependence persist, while the inherent low signal-to-noise ratio of EEG signals remains a critical aspect that demands attention. Accurately deciphering intentions from EEG signals continues to present a formidable challenge. This paper introduces an advanced end-to-end network that effectively combines the efficient channel attention (ECA) and temporal convolutional network (TCN) components for the classification of motor imagination signals. We incorporated an ECA module prior to feature extraction in order to enhance the extraction of channel-specific features. A compact convolutional network model uses for feature extraction in the middle part. Finally, the time characteristic information is obtained by using TCN. The results show that our network is a lightweight network that is characterized by few parameters and fast speed. Our network achieves an average accuracy of 80.71% on the BCI Competition IV-2a dataset.


Assuntos
Algoritmos , Interfaces Cérebro-Computador , Humanos , Redes Neurais de Computação , Imaginação , Eletroencefalografia/métodos , Atenção
4.
Zhongguo Zhong Yao Za Zhi ; 48(13): 3612-3622, 2023 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-37474994

RESUMO

This study aimed to analyze the effect of Bletilla striata polysaccharide(BSP) on endogenous metabolites in serum of tumor-bearing mice treated with 5-fluorouracil(5-FU) by untargeted metabolomics techniques and explore the mechanism of BSP in alleviating the toxic and side effects induced by 5-FU. Male BALB/C mice were randomly divided into a normal group, a model group, a 5-FU group, and a 5-FU + BSP group, with eight mice in each group. Mouse colon cancer cells(CT26) were transplanted into the mice except for those in the normal group to construct the tumor-bearing mouse model by subcutaneous injection, and 5-FU chemotherapy and BSP treatment were carried out from the second day of modeling. The changes in body weight, diarrhea, and white blood cell count in the peripheral blood were recorded. The mice were sacrificed and sampled when the tumor weight of mice in the model group reached approximately 1 g. TUNEL staining was used to detect the cell apoptosis in the small intestine of each group. The proportions of hematopoietic stem cells and myeloid progenitor cells in bone marrow were measured by flow cytometry. Five serum samples were selected randomly from each group for untargeted metabolomics analysis. The results showed that BSP was not effective in inhibiting colon cancer in mice, but diarrhea, leukopenia, and weight loss caused by 5-FU chemotherapy were significantly improved after BSP intervention. In addition, apoptotic cells decreased in the small intestinal tissues and the percentages of hematopoietic stem cells and myeloid progenitor cells in bone marrow were significantly higher after BSP treatment. Metabolomics results showed that the toxic and side effects of 5-FU resulted in significant decrease in 29 metabolites and significant increase in 22 metabolites in mouse serum. Among them, 19 disordered metabolites showed a return to normal levels in the 5-FU+BSP group. The results of pathway enrichment indicated that metabolic pathways mainly involved pyrimidine metabolism, arachidonic acid metabolism, and steroid hormone biosynthesis. Therefore, BSP may ameliorate the toxic and side effects of 5-FU in the intestinal tract and bone marrow presumably by regulating nucleotide synthesis, inflammatory damage, and hormone production.


Assuntos
Neoplasias do Colo , Fluoruracila , Animais , Masculino , Camundongos , Neoplasias do Colo/tratamento farmacológico , Diarreia , Fluoruracila/efeitos adversos , Hormônios , Metabolômica , Camundongos Endogâmicos BALB C , Polissacarídeos/farmacologia
5.
Zhongguo Zhong Yao Za Zhi ; 48(4): 1043-1053, 2023 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-36872275

RESUMO

This paper aimed to study the effect of Dalbergia cochinchinensis heartwood on plasma endogenous metabolites in rats with ligation of the left anterior descending coronary artery, and to analyze the mechanism of D. cochinchinensis heartwood in improving acute myocardial ischemic injury. The stability and consistency of the components in the D. cochinchinensis heartwood were verified by the establishment of fingerprint, and 30 male SD rats were randomly divided into a sham group, a model group, and a D. cochinchinensis heartwood(6 g·kg~(-1)) group, with 10 rats in each group. The sham group only opened the chest without ligation, while the other groups established the model of ligation. Ten days after administration, the hearts were taken for hematoxylin-eosin(HE) staining, and the content of heart injury indexes in the plasma creatine kinase isoenzyme(CK-MB) and lactate dehydrogenase(LDH), energy metabolism-related index glucose(Glu) content, and vascular endothelial function index nitric oxide(NO) was determined. The endogenous metabolites were detected by ultra-high-performance liquid chromatography-time-of-flight-mass spectrometry(UPLC-Q-TOF-MS). The results showed that the D. cochinchinensis heartwood reduced the content of CK-MB and LDH in the plasma of rats to relieve myocardial injury, reduced the content of Glu in the plasma, improved myocardial energy metabolism, increased the content of NO, cured the vascular endothelial injury, and promoted vasodilation. D. cochinchinensis heartwood improved the increase of intercellular space, myocardial inflammatory cell infiltration, and myofilament rupture caused by ligation of the left anterior descending coronary artery. The metabolomic study showed that the content of 26 metabolites in the plasma of rats in the model group increased significantly, while the content of 27 metabolites decreased significantly. Twenty metabolites were significantly adjusted after the administration of D. cochinchinensis heartwood. D. cochinchinensis heartwood can significantly adjust the metabolic abnormality in rats with ligation of the left anterior descending coronary artery, and its mechanism may be related to the regulation of cardiac energy metabolism, NO production, and inflammation. The results provide a corresponding basis for further explaining the effect of D. cochinchinensis on the acute myocardial injury.


Assuntos
Dalbergia , Traumatismos Cardíacos , Isquemia Miocárdica , Masculino , Animais , Ratos , Ratos Sprague-Dawley , Metabolômica , Coração , Creatina Quinase Forma MB
6.
Food Chem ; 404(Pt A): 134482, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36252380

RESUMO

Hormone residues in food and drinking water endanger human health, therefore, on-site analysis techniques of superior performance are important for monitoring this risk. In this study, an ultra-sensitive photothermal lateral flow immunoassay (LFIA) for quantification of 17ß-estradiol (E2) has been developed. Anti-E2 antibody modified black phosphorus-Au (BP-Au) nanocomposite was developed as a photothermal contrast signal probe and the temperature at test-zone was recorded with an infrared camera. Under the irradiation of 808 nm laser at test-zone, it gave temperatures negatively related to the concentrations of E2 in samples. Under optimal detecting conditions, the developed photothermal LFIA exhibited a limit of detection of 50 pg mL-1, over 100-fold more sensitive than visual LFIA, and a linear range of 3 orders of magnitude. This method has been successfully applied to water, milk, and milk powder samples.


Assuntos
Estradiol , Leite , Humanos , Animais , Limite de Detecção , Imunoensaio/métodos , Estradiol/análise , Leite/química , Fósforo/análise , Anticorpos , Ouro/química
7.
J Am Chem Soc ; 144(39): 17776-17782, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-36136777

RESUMO

A mild and site-selective hydroaminoalkylation of activated and unactivated alkenes via dual photoredox/Ni catalysis is developed. This dual catalytic strategy enables exclusive access to α-selective products, which is complementary to previously reported photocatalytic hydroaminoalkylation of activated alkenes that provides the ß-selective products. The chain-walking of a Ni-H intermediate toward a carbonyl allows for the hydroaminoalkylation of unactivated alkenes at remote sp3 C-H sites. This method tolerates a broad substrate scope of both amines and alkenes as well as providing a streamlined synthesis of value-added ß-amino acid derivatives from readily available starting materials.


Assuntos
Alcenos , Níquel , Alcenos/química , Aminas/química , Aminoácidos , Catálise , Níquel/química
8.
Se Pu ; 40(8): 686-693, 2022 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-35903835

RESUMO

Amino acids are important building blocks of proteins in the human body, which are involved in many metabolic pathways. Patients with metabolic diseases such as phenylketonuria, tyrosinemia, and hepatic encephalopathy are genetically defective and cannot metabolize aromatic amino acids (AAA) in food; hence, a regular diet may lead to permanent physiological damage. For this reason, it is necessary to restrict the intake of AAA in their daily diet by limiting natural protein intake, while ensuring normal intake of low protein foods and supplementation with low-AAA protein equivalents. Sources of low-AAA protein equivalents currently rely on free amino acid complex mixtures and low-AAA peptides (also known as high-Fischer-ratio peptides), which have better absorption availability and palatability. AAA separation and analysis techniques are essential for the preparation and detection of low-AAA peptides. Researchers in this field have explored a variety of efficient adsorption materials to selectively remove AAA from complex protein hydrolysates and thus prepare low-AAA peptide foods, or to establish analysis strategies for AAA. Covering more than 70 publications on AAA removal and separation in the last decade from Web of Science Core Collection and China National Knowledge Infrastructure, this review analyzes the structural characteristics and physicochemical properties of AAA, and summarizes the technological progress of AAA removal based on adsorbents such as activated carbon and resin. The applications of two-dimensional nanomaterials, molecular imprinting, cyclodextrins, and metal-organic frameworks in AAA adsorption and analysis from three dimensions, i. e., sample pretreatment, chiral separation and adsorption sensing, are also reviewed. The mainstream adsorbents for AAA removal, such as activated carbon, still suffer from poor specificity and cause environmental pollution during post-use treatment. Existing AAA separating materials show impressive selective adsorption capability in food samples and chiral mixtures as well as high sensitivity in adsorption sensing. The development of an efficient detection technology for AAA may help in detecting trace AAA in food and in evaluating chiral AAA adulteration in food samples. By exploring the advantages and disadvantages of each type of technology, we provide support for the advancement of the removal and analysis techniques for AAA.


Assuntos
Aminoácidos Aromáticos , Carvão Vegetal , Adsorção , Aminoácidos , Aminoácidos Aromáticos/química , Humanos , Peptídeos
9.
Oxid Med Cell Longev ; 2022: 6316611, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35313639

RESUMO

Chlorogenic acid (CGA), as one of the richest polyphenol compounds in nature, has broad applications in many fields due to its various biological properties. However, initial data on the effects of dietary CGA on protein synthesis and related basal metabolic activity has rarely been reported. The current study is aimed at (1) determining whether dietary CGA supplementation improves the growth performance and carcass traits, (2) assessing whether dietary CGA alters the free amino acid profile, and (3) verifying whether dietary CGA promotes muscle protein synthesis in finishing pigs. Thirty-two (Large × White × Landrace) finishing barrows with an average initial body weight of 71.89 ± 0.92 kg were randomly allotted to 4 groups and fed diets supplemented with 0, 0.02%, 0.04%, and 0.08% CGA, respectively. The results indicated that, compared with the control group, dietary supplementation with 0.04% CGA slightly stimulated the growth performance of pigs, whereas no significant correlation was noted between the dietary CGA levels and animal growth (P > 0.05). Furthermore, the carcass traits of pigs were improved by 0.04% dietary CGA (P < 0.01). In addition, dietary CGA significantly improved the serum free amino acid profiles of pigs (P < 0.01), while 0.04% dietary CGA promoted more amino acids to translocate to skeletal muscles (P < 0.05). The relative mRNA expression levels of SNAT2 in both longissimus dorsi (LD) and biceps femoris (BF) muscles were augmented in the 0.02% and 0.04% groups (P < 0.05), and the LAT1 mRNA expression in the BF muscle was elevated in the 0.02% group (P < 0.05). We also found that dietary CGA supplementation at the levels of 0.04% or 0.08% promoted the expression of p-Akt and activated the mTOR-S6K1-4EBP1 axis in the LD muscle (P < 0.05). Besides, the MAFbx mRNA abundance in the 0.02% and 0.04% groups was significantly lower (P < 0.05). Our results revealed that dietary supplementation with CGA of 0.04% improved the free amino acid profile and enhanced muscle protein biosynthesis in the LD muscle in finishing pigs.


Assuntos
Aminoácidos , Lonicera , Aminoácidos/metabolismo , Ração Animal/análise , Animais , Ácido Clorogênico/farmacologia , Suplementos Nutricionais , Lonicera/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Biossíntese de Proteínas , Suínos
10.
Chemosphere ; 291(Pt 3): 133027, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34822865

RESUMO

Amino trimethylene phosphonic acid (ATMP) was widely used as an antiscalant in reverse osmosis (RO) systems to prevent membrane scaling, and entered RO concentrate at elevated levels. However, phosphonate antiscalants in RO concentrate might aggravate phosphorus pollution, remobilize heavy metals, and adversely affect the sedimentation treatment of RO concentrate. Ozonation was found an efficient method for ATMP treatment. The ATMP removal efficiencies with 8 mg/L ozone were 100% and 86.5% for ultrapure water and RO concentrate, respectively. The ATMP mineralization efficiency reached 46.5% with 8 mg/L ozone. The rate constant for the reaction between ATMP and ozone was 1.92 × 106 M-1 s-1. Increasing the pH from 3 to 9 decreased the ATMP removal efficiency from 90% to 30.9% but increased the orthophosphate formation to ATMP removal ratio from 0.11 to 0.48. The ATMP intermediates generated with low ozone dosages exhibited moderate chelation and anti-precipitation capacity, and their chelation and anti-precipitation capacity could be further attenuated by increasing the ozone dosage. Ozonation alone enhanced the growth potential for microalgae in RO concentrate because orthophosphate formed. Combining ozonation and coagulation effectively removed 83.0% of the total phosphorus from RO concentrate. The maximum algal density of Scenedesmus sp. LX1 decreased by 78.7% by ozonation and coagulation.


Assuntos
Ozônio , Purificação da Água , Aminoácidos , AMP Cíclico/análogos & derivados , Osmose , Ácidos Fosforosos , Fósforo
11.
J Sci Food Agric ; 102(9): 3796-3807, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34921408

RESUMO

BACKGROUND: Pork is an important food for humans and improving the quality of pork is closely related to human health. This study was designed to investigate the effects of balanced branched-chain amino acid (BCAA)-supplemented protein-restricted diets on meat quality, muscle fiber types, and intramuscular fat (IMF) in finishing pigs. RESULTS: The results showed that, compared with the normal protein diet (160 g kg-1 crude protein), the reduced-protein diet (120 g kg-1 crude protein) supplemented with BCAAs to the ratio of 2:1:2 not only had higher average daily gain (P < 0.05) and carcass weight (P < 0.05) but also improved meat tenderness and juiciness by decreasing shear force (P < 0.05) and increasing water-holding capacity (P < 0.05). In particular, this treatment showed higher (P < 0.05) levels of phospho-acetyl-CoA carboxylase (P-ACC) and peroxisome proliferation-activated receptor-γ (PPARγ), and lower (P < 0.05) levels of P-adenosine 5'-monophosphate (AMP)-activated protein kinase (P-AMPK), increasing the composition of IMF and MyHC I (P < 0.05) in the longissimus dorsi muscle (LDM). In terms of health, this group increased eicosapentaenoic acid (EPA) (P < 0.01) and desirable hypocholesterolemic fatty acids (DHFA) (P < 0.05), and decreased atherogenicity (AI) (P < 0.01) and hypercholesterolemic saturated fatty acids (HSFA) (P < 0.05). CONCLUSION: Our findings suggest a novel role for a balanced BCAA-supplemented restricted protein (RP) diet in the epigenetic regulation of more tender and healthier pork by increasing IMF deposition and fiber type conversion, providing a cross-regulatory molecular basis for revealing the nutritional regulation network of meat quality. © 2021 Society of Chemical Industry.


Assuntos
Aminoácidos de Cadeia Ramificada , Epigênese Genética , Aminoácidos de Cadeia Ramificada/metabolismo , Ração Animal/análise , Dieta com Restrição de Proteínas , Ácidos Graxos/química , Carne , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Suínos
12.
Sci Total Environ ; 808: 152118, 2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-34863744

RESUMO

Because the disposal of phosphogypsum (PG) can lead to serious contamination of the air, soil, and water, recycling of PG has attracted wide attention. This study investigated the effect and solidification of phosphorus in the production of calcium sulfoaluminate (CSA) cement using PG as the sole CaO source. The effects of three phosphorus impurities (Ca3(PO4)2, CaHPO4, Ca(H2PO4)2) on the decomposition of CaSO4, formation of minerals, microstructure of the clinker, and the hydration and mechanical properties of the cement were studied. Experimental results show that Ca3(PO4)2 and Ca(H2PO4)2 promoted the decomposition of CaSO4 and the formation of clinker minerals with the increase in P2O5 content, whereas CaHPO4 showed a promoting effect only when the P2O5 content was more than 1.5 wt%. The increase in phosphorus incorporation in Ca2SiO4 leads to the transformation of ß-Ca2SiO4 to α'-Ca2SiO4 and then to Ca7Si2P2O16. The presence of three phosphates in the clinker enhanced the growth of crystal grains and the generation of a liquid phase. Compared with Ca4Al6SO16 without phosphorus, the hydration reaction of phosphorus-bearing Ca4Al6SO16 started later and ended earlier, and the reaction time was shorter. The presence of phosphorus impurities reduces the 1-day strength of CSA cement but does not affect the development of the 3-day and 28-day strengths. Considering environmental aspects, the solidification of phosphorus in the production of CSA clinker were quantified by measuring the distribution of elements. The results indicated that phosphorus is solidified by Ca4Al6SO16, Ca2SiO4, and Ca4Al2Fe2O10, and Ca2SiO4 has a stronger ability to solidify phosphorus than the other two minerals. Ca3(PO4)2 is more difficult to solidify than CaHPO4 and Ca(H2PO4)2. This study is of great significant to guide the large-scale clean utilization of PG in the production of CSA cement.


Assuntos
Compostos de Cálcio , Fósforo , Compostos de Alumínio , Sulfato de Cálcio , Óxidos , Compostos de Enxofre
13.
J Agric Food Chem ; 69(25): 7037-7048, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34110799

RESUMO

This study aimed to investigate the effect of the supplementation of branched-chain amino acids (BCAAs) at different ratios in protein restriction diets on lipid metabolism in a finishing pig model. The BCAA supplementation (leucine/isoleucine/valine = 2:1:1 and 2:1:2) ameliorated the poor growth performance and carcass characteristics, particularly high fat mass caused by a protein-restricted diet. Serum adiponectin increased while leptin decreased in BCAA diets in comparison to the 12% CP group. BCAA supplementation also increased the low-protein expression of AMPK and SIRT1 caused by protein restriction. The mRNA and protein levels of peroxisome proliferation-activated receptor-γ (PPARγ) and acetyl-CoA carboxylase (ACC) were highest in the protein-restricted group and lowered in the 2:1:1 or 2:1:2 group. In conclusion, BCAAs supplemented in an adequate ratio range of 2:1:1 to 2:1:2 (2:1:2 is recommended) in reduced protein diets could modulate lipid metabolism by accelerating the secretion of adipokines and fatty acid oxidation.


Assuntos
Aminoácidos de Cadeia Ramificada , Metabolismo dos Lipídeos , Aminoácidos de Cadeia Ramificada/metabolismo , Dieta com Restrição de Proteínas , Leptina , Oxirredução , Suínos
14.
Sci Total Environ ; 772: 145540, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33770870

RESUMO

Soil erodibility is an indispensable parameter for predicting soil erosion and evaluating the benefits of soil and water conservation. Slope situation can alter revegetation and its effects on soil properties and root traits, and thus may affect soil erodibility. However, whether slope situation will change the effect of revegetation on soil erodibility through improving soil properties and root traits has rarely been evaluated. Therefore, this study was conducted to detect the response of soil erodibility to slope situations (loess-tableland, hill-slope and gully-slope) in a typical watershed of the Loess Plateau. Five soil erodibility parameters (saturated soil hydraulic conductivity, SHC; mean weight diameter of aggregates, MWD; clay ratio, CR; soil disintegration rate, SDR; soil erodibility factor, K) and a comprehensive soil erodibility index (CSEI) are selected to clarify the study targets. The results revealed that soil properties, root traits, soil erodibility parameters and CSEI were affected by slope situation significantly. Soil and root can explain 79.7%, 79.1% and 69.8% of total variance in soil erodibility of loess-tableland, hill-slope and gully-slope, respectively. Slope situation influenced soil erodibility by changing the effects of revegetation on soil properties and root traits. Evidently, the slope situation greatly changed the relations between CSEI and soil and root parameters, whereafter a model considering slope situation (slope steepness), sand, organic matter content and root surface area density was reliable to estimate soil erodibility (CSEI). Our study suggested that the Armeniaca sibirica, the combination of Bothriochloa ischcemum and Robinia pseudoacacia and the combination of Armeniaca sibirica and Lespedeza bicolor can be used as the optimal selection for mitigating soil erodibility of loess-tableland, hill-slope and gully-slope, respectively. This study is of great significance in optimizing the spatial layout of soil and water conservation measures for different slope situations of the Loess Plateau.


Assuntos
Robinia , Solo , China , Poaceae
15.
ACS Appl Bio Mater ; 4(6): 4821-4832, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35007031

RESUMO

Antibiotics are widely used for treatment of bacterial infections, and their overuse has contributed to microbial resistance. Currently, an alternative antibiotic-free therapy for inactivating bacteria is of great interest. Black phosphorus (BP), a biocompatible and nontoxic rising-star two-dimensional layered material, has gained remarkable interest in many bioapplications including biosensing, cancer therapy, drug delivery, and also antibacterial treatment. However, BP nanosheets suffer from instability in ambient environments due to rapid oxidation and degradation. To address this issue, BP nanosheets were modified with quaternized chitosan (QCS) by electrostatic adsorption to prepare a BP-QCS composite for photothermal/pharmaco treatment of bacterial infection. The BP-QCS has obviously enhanced solubility and chemical stability in aqueous suspensions. We have demonstrated that under near-infrared (NIR) irradiation, the BP-QCS can synergistically inactivate more than 95% methicillin-resistant Staphylococcus aureus (S. aureus) (MRSA) and Escherichia coli within 10 min with a dose of only 75 µg/mL in vitro. Meanwhile, the BP-QCS composite under NIR can synergistically inactivate 98% S. aureus in vivo. Furthermore, the BP-QCS suspensions at effective antibacterial concentrations have negligible cytotoxicity and in vivo toxicity.


Assuntos
Antibacterianos/administração & dosagem , Quitosana/administração & dosagem , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Nanocompostos/administração & dosagem , Fósforo/administração & dosagem , Infecções Estafilocócicas/tratamento farmacológico , Células 3T3 , Animais , Antibacterianos/química , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Desinfecção/métodos , Sistemas de Liberação de Medicamentos , Farmacorresistência Bacteriana , Sinergismo Farmacológico , Escherichia coli/crescimento & desenvolvimento , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos BALB C , Nanocompostos/química , Fósforo/química , Compostos de Amônio Quaternário/química
16.
J Environ Manage ; 271: 110986, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32778279

RESUMO

As the disposal of phosphogypsum can result in severe contamination of soil and groundwater, several researchers worldwide have devoted efforts toward realizing suitable methods for PG disposal. This study demonstrates the feasibility of using phosphogypsum as the sole CaO source in the preparation of calcium sulfoaluminate cement by considering its mechanical properties and the potential environmental impacts of its large-scale utilization. First, the effects of the alumina/silica ratio on the mineral phase formation, setting time, compressive strength, and microstructure of calcium sulfoaluminate cement were studied. An alumina/silica ratio of 2.0 or 2.5 resulted in satisfactory mineral phase formation and compressive strength; the compressive strength of calcium sulfoaluminate cement reached 63.2, 88.5, and 100.2 MPa after 1, 3, and 28 d of curing, respectively. Second, the environmental behaviors of harmful impurities in the raw materials and calcium sulfoaluminate cement were investigated. In the static leaching and acid leaching tests, the concentrations of harmful elements in the calcium sulfoaluminate cement leachates met the requirements of national standards (GB/T14848-2007). After a period of curing, P and some heavy metals (Mn, Cr, Ni, Cu, and As) did not leach from the cement. Finally, a novel process and a system of preparing CSA cement by using phosphogypsum as the sole CaO source are proposed. This novel technology could be employed as a reliable and environment friendly means of recycling phosphogypsum in the large-scale preparation of calcium sulfoaluminate cement.


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Sulfato de Cálcio , Óxidos , Fósforo , Compostos de Enxofre
17.
Front Physiol ; 11: 449, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547405

RESUMO

Background: Intestinal barrier contributes as an important role in maintaining intestinal homeostasis. Oxidative stress can cause critical damages in intestinal integrity of animals. Objectives: This study was conducted to investigate the alleviated effect of taurine against small intestine (duodenum, jejunum, ileum) injury induced by oxidative stress. Methods: The piglet model of diquat-induced oxidative stress was employed. In addition, analysis of intestinal morphology, reverse transcription PCR (RT-PCR), and Western blot were used in this study. Results: Compared with the control group (CON), diquat-induced oxidative stress triggers immune response; the content of immunoglobulin M (IgM) and immunoglobulin G (IgG) was significantly changed, but 0.60% taurine supplementation could restore the level of serum immunoglobulin. Oxidative stress induces serious damage in intestinal morphology structure and tight junction barrier. Compared with the CON, the villus height of intestine was significantly decreased, the crypt depth and villus height/crypt depth (V/C) were also decreased, and 0.60% taurine supplementation could restore impaired morphology and even improve crypt depth and V/C of the jejunum and ileum. Compared with the CON, oxidative stress markedly increased the messenger RNA (mRNA) expression level of claudin-1 and occludin in the duodenum, and the value of occludin was significantly decreased in the jejunum of the diquat group (DIQ). Relative to the DIQ, 0.60% taurine supplementation increased the mRNA expression level of claudin-1, occludin, and ZO-1 in the ileum. Compared with the CON, the expression of claudin-1 protein was significantly upregulated, and occludin and ZO-1 protein were both downregulated in the small intestine of DIQ. Conclusion: Taurine exerts protective effects by regulating immune response and restores the intestinal tight junction barrier when piglets suffer from oxidative stress.

18.
J Anim Sci Biotechnol ; 11: 56, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32514342

RESUMO

BACKGROUND: Oxidative stress is a key factor that influences piglets' health. Taurine plays an imperative role in keeping the biological system from damage. This study was conducted to investigate the protective effect of taurine against muscle injury due to the secondary effect of diquat toxicity. RESULTS: Our study found that taurine effectively and dose-dependently alleviated the diquat toxicity induced rise of feed/gain, with a concurrent improvement of carcass lean percentage. The plasma content of taurine was considerably increased in a dose-dependent manner. Consequently, dietary taurine efficiently improved the activity of plasma antioxidant enzymes. Furthermore, taurine attenuated muscle damage by restoring mitochondrial micromorphology, suppressing protein degradation and reducing the percentage of apoptotic cells in the skeletal muscle. Taurine supplementation also suppressed the genes expression levels of the antioxidant-, mitochondrial biogenesis-, and muscle atrophy-related genes in the skeletal muscle of piglets with oxidative stress. CONCLUSIONS: These results showed that the dose of 0.60% taurine supplementation in the diet could attenuate skeletal muscle injury induced by diquat toxicity. It is suggested that taurine could be a potential nutritional intervention strategy to improve growth performance.

19.
Nutrients ; 12(5)2020 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-32370170

RESUMO

Lipid metabolism is an important and complex biochemical process involved in the storage of energy and maintenance of normal biological functions. Leucine, a branched amino acid, has anti-obesity effects on glucose tolerance, lipid metabolism, and insulin sensitivity. Leucine also modulates mitochondrial dysfunction, representing a new strategy to target aging, neurodegenerative disease, obesity, diabetes, and cardiovascular disease. Although various studies have been carried out, much uncertainty still exists and further studies are required to fully elucidate the relationship between leucine and lipid metabolism. This review offers an up-to-date report on leucine, as key roles in both lipid metabolism and energy homeostasis in vivo and in vitro by acceleration of fatty acid oxidation, lipolysis, activation of the adenosine 5'-monophosphate-activated protein kinase (AMPK)-silent information regulator of transcription 1 (SIRT1)-proliferator-activated receptor γ coactivator-1α (PGC-1α) pathway, synthesis, and/or secretion of adipokines and stability of the gut microbiota.


Assuntos
Suplementos Nutricionais , Metabolismo Energético/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Leucina/administração & dosagem , Leucina/fisiologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição/fisiologia , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Fármacos Antiobesidade , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus/prevenção & controle , Ácidos Graxos/metabolismo , Intolerância à Glucose/prevenção & controle , Humanos , Resistência à Insulina , Leucina/metabolismo , Leucina/farmacologia , Lipólise/efeitos dos fármacos , Doenças Neurodegenerativas/prevenção & controle , Oxirredução/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Sirtuína 1/metabolismo
20.
Sci China Life Sci ; 63(6): 866-874, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31705360

RESUMO

Free radical-induced oxidative stress contributes to the development of metabolic syndromes (Mets), including overweight, hyperglycemia, insulin resistance and pro-inflammatory state. Most free radicals are generated from the mitochondrial electron transport chain; under physiological conditions, their levels are maintained by efficient antioxidant systems. A variety of transcription factors have been identified and characterized that control gene expression in response to oxidative stress status. Natural antioxidant compounds have been largely studied for their strong antioxidant capacities. This review discusses the recent progress in oxidative stress and mitochondrial dysfunction in Mets and highlights the anti-Mets, anti-oxidative, and anti-inflammatory effect of polyphenols as potential nutritional therapy.


Assuntos
Antioxidantes/farmacologia , Produtos Biológicos/farmacologia , Síndrome Metabólica/terapia , Distúrbios Nutricionais/terapia , Estresse Oxidativo/efeitos dos fármacos , Polifenóis/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/uso terapêutico , Produtos Biológicos/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Terapia Nutricional/métodos , Polifenóis/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo
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