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1.
Sensors (Basel) ; 24(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38610480

RESUMO

During the process of reverse parking, it is difficult to achieve the ideal reference trajectory while avoiding collision. In this study, with the aim of establishing reference trajectory optimization for automatic reverse parking that smooths and shortens the trajectory length and ensures the berthing inclination angle is small enough, an improved immune moth-flame optimization method based on gene correction is proposed. Specifically, based on the standard automatic parking plane system, a reasonable high-quality reference trajectory optimization model for automatic parking is constructed by combining the cubic spline-fitting method and a boundary-crossing solution based on gene correction integrated into moth-flame optimization. To enhance the model's global optimization performance, nonlinear decline strategies, including crossover and variation probability and weight coefficient, and a high-quality solution-set maintenance mechanism based on fusion distance are also designed. Taking garage No.160 of the Dalian Shell Museum located in Dalian, Xinghai Square, as the experimental site, experiments on automatic parking reference trajectory optimization and tracking control were carried out. The results show that the proposed optimization algorithm provides higher accuracy for reference trajectory optimization and can achieve better tracking control of the reference trajectory.

2.
Curr Biol ; 34(2): 389-402.e5, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38215742

RESUMO

Aversive stimuli activate corticotropin-releasing factor (CRF)-expressing neurons in the paraventricular nucleus of hypothalamus (PVNCRF neurons) and other brain stress systems to facilitate avoidance behaviors. Appetitive stimuli also engage the brain stress systems, but their contributions to reward-related behaviors are less well understood. Here, we show that mice work vigorously to optically activate PVNCRF neurons in an operant chamber, indicating a reinforcing nature of these neurons. The reinforcing property of these neurons is not mediated by activation of the hypothalamic-pituitary-adrenal (HPA) axis. We found that PVNCRF neurons send direct projections to the ventral tegmental area (VTA), and selective activation of these projections induced robust self-stimulation behaviors, without activation of the HPA axis. Similar to the PVNCRF cell bodies, self-stimulation of PVNCRF-VTA projection was dramatically attenuated by systemic pretreatment of CRF receptor 1 or dopamine D1 receptor (D1R) antagonist and augmented by corticosterone synthesis inhibitor metyrapone, but not altered by dopamine D2 receptor (D2R) antagonist. Furthermore, we found that activation of PVNCRF-VTA projections increased c-Fos expression in the VTA dopamine neurons and rapidly triggered dopamine release in the nucleus accumbens (NAc), and microinfusion of D1R or D2R antagonist into the NAc decreased the self-stimulation of these projections. Together, our findings reveal an unappreciated role of PVNCRF neurons and their VTA projections in driving reward-related behaviors, independent of their core neuroendocrine functions. As activation of PVNCRF neurons is the final common path for many stress systems, our study suggests a novel mechanism underlying the positive reinforcing effect of stressful stimuli.


Assuntos
Hormônio Liberador da Corticotropina , Hormônios Liberadores de Hormônios Hipofisários , Camundongos , Animais , Hormônio Liberador da Corticotropina/metabolismo , Hormônios Liberadores de Hormônios Hipofisários/metabolismo , Hormônios Liberadores de Hormônios Hipofisários/farmacologia , Sistema Hipotálamo-Hipofisário , Sistema Hipófise-Suprarrenal , Hipotálamo/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Neurônios Dopaminérgicos/metabolismo
3.
Food Chem ; 439: 138099, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039613

RESUMO

Heating edible oils generates aldehydes, potentially leading to adverse health effects, making their analysis essential for quality control. This study presents a convenient miniaturized kapok fiber-supported liquid-phase extraction/in-situ derivatization method for the simultaneous extraction and derivatization of aldehydes in oils. The method involves placing 150 mg oil into a 1 mL pipette tip packed with 25 mg kapok fiber, adding 150 µL ACN with 1.5 mg mL-1 DNPH, and post 30-minute static extraction, retrieving the extractant with a pipettor for liquid chromatography-tandem mass spectrometry analysis. By optimizing critical parameters through a Box-Behnken design, the method exhibits good linearity (1-500 ng g-1, R2 ≥ 0.991), low detection limits (0.2-1.0 ng g-1), excellent accuracy (95.3-107.1%) and high precisions (relative standard deviation < 7.9%). This method simplifies sample preparation processes, cuts solvent use, and facilitates automation. It effectively identifies ten aldehyde variations in six heated oils, displaying distinct profiles consistent with prior research.


Assuntos
Aldeídos , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Aldeídos/análise , Cromatografia Líquida , Extração Líquido-Líquido/métodos , Óleos de Plantas/química , Cromatografia Líquida de Alta Pressão/métodos
4.
Chem Biodivers ; 21(2): e202301826, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38155523

RESUMO

Marine fungi represent a huge untapped resource of natural products. The bio-activity of a new asperbutenolide A from marine fungus Aspergillus terreus was not well known. In the present study, the minimum inhibitory concentration (MIC) and RNA-Sequencing were used to analyze the bio-activity and sterilization mechanism of asperbutenolide A against clinical pathogenic microbes. The results showed that the MICs of asperbutenolide A against methicillin-resistant Staphylococcus aureus (MRSA) were 4.0-8.0 µg/mL. The asperbutenolide A present poor bio-activity against with candida. The sterilization mechanism of asperbutenolide A against MRSA showed that there were 1426 differentially-expressed genes (DEGs) between the groups of MRSA treated with asperbutenolide A and negative control. Gene Ontology (GO) classification analysis indicated that the DEGs were mainly involved in cellular process, metabolic process, cellular anatomical entity, binding, catalytic activity, etc. Kyoto Encyclopedia of Genes and Genomes (KEGG) classification analysis showed that these DEGs were mainly enriched in amino acid metabolism, carbohydrate metabolism, membrane transport, etc. Moreover, qRT-PCR showed similar trends in the expressions of argF, ureA, glmS and opuCA with the RNA-Sequencing. These results indicated that asperbutenolide A was with ideal bio-activity against with MRSA and could be as a new antibacterial agent.


Assuntos
4-Butirolactona/análogos & derivados , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Infecções Estafilocócicas/tratamento farmacológico , Testes de Sensibilidade Microbiana , Fungos , RNA
5.
Food Chem ; 428: 136839, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37429242

RESUMO

Furfurals (5-hydroxymethylfurfural, furfural and 5-methyl furfural) have potential toxic effects to humans. This study developed a simple and rapid one-pot derivatization/extraction procedure for effective sample preparation of furfurals in complex samples prior to instrument analysis. The sample solution was incubated with 1-pyrenebutyric hydrazide (PBH) and hydroxyl-functionalized multi-walled carbon nanotubes (MWCNTs-OH) in a vial for 3 min. During this process, the furfurals were effectively derivatized by PBH and the furfural-PBH derivatives were selectively captured by MWCNTs-OH simultaneously. The detection selectivity and accuracy were greatly improved for the following liquid chromatography-tandem mass spectrometry analysis. Quantifying furfurals was validated over the 0.5-500 ng/mL concentration range with satisfactory linearities (R2 >0.99), accuracies (84.7%-119.0%) and precisions (<9.0%). The limits of quantification of 0.30, 0.36 and 0.20 ng/mL for 5-hydroxymethylfurfural, furfural and 5-methyl furfural, respectively, were achieved. Finally, the validated method was successfully applied to determine furfurals concentrations in various samples.


Assuntos
Furaldeído , Nanotubos de Carbono , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Nanotubos de Carbono/química , Cromatografia Líquida/métodos , Extração em Fase Sólida/métodos
6.
Talanta ; 260: 124618, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37156209

RESUMO

Protein-rich aqueous samples such as milk and plasma usually require complex sample preparation steps prior to instrumental analysis. This study proposed a novel cotton fiber-supported liquid extraction (CF-SLE) method for convenient sample preparation. Natural cotton fiber was directly loaded into a syringe tube to conveniently construct the extraction device. No filter frits were required due to the fibrous feature of the cotton fibers. The cost of the extraction device was less than 0.5 CNY, and the costly syringe tube could be easily reused to decrease the cost further. Extraction used a simple two-step protocol: protein-rich aqueous sample loading and elution. Emulsification and centrifugation steps involved in the classic liquid-liquid extraction were avoided. As a proof-of-concept study, the glucocorticoids in milk and plasma were extracted with satisfactory extraction recoveries. Coupled with liquid chromatography-tandem mass spectrometry, a sensitive quantification method was established with excellent linearity (R2 > 0.991) as well as good accuracy (85.7-117.3%) and precision (<14.3%). This system is simple, low-cost, reproducible, and easy to automate. Thus, the proposed CF-SLE method is promising for the routine sample preparation of protein-rich aqueous samples prior to instrumental analysis.


Assuntos
Leite , Animais , Cromatografia Líquida de Alta Pressão , Fibra de Algodão , Glucocorticoides/análise , Leite/química , Extração em Fase Sólida/métodos , Água/análise
7.
J Chromatogr A ; 1698: 464004, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37094539

RESUMO

The current study proposed a novel feather fiber-supported liquid extraction (FF-SLE) method for extracting analytes from oil samples. The natural feather fibers were used as the oil support material and directly loaded in the plastic tube of a disposable syringe to construct the low-cost extraction device (∼0.5 CNY). The edible oil without any pretreatment including dilution was added directly to the extraction device, followed by the addition of the green extraction solvent of ethanol. As an example, the proposed method was applied to extract nine synthetic antioxidants from edible oils. The optimized extraction conditions for processing 0.5 g of oil were obtained when the syringe dimension was 5 mL, the extraction solvent was 0.5 mL of ethanol, the amount of feather fibers was 200 mg of duck feather fibers and the static extraction time was 10 min. The applications to seven kinds of feathers and seven kinds of edible oils all indicated the excellent oil removal efficiencies (>98.0%). Combined with high-performance liquid chromatography-ultraviolet, a quantification method was validated with satisfied linearity (R2≥0.994), accuracy (95.8-114.6%) and precision (≤8.3%) with the limits of detection ranging from 50 to 100 ng/g. The proposed FF-SLE method was simple, effective, convenient, low-cost, green and environmental-friendly for the extraction of analytes from oil samples prior to instrument analysis.


Assuntos
Antioxidantes , Animais , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão/métodos , Etanol , Plumas/química , Óleos de Plantas/análise , Solventes
8.
Food Chem ; 415: 135788, 2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-36854240

RESUMO

This study presents an in-pipette-tip kapok fiber-supported liquid extraction/in-situ derivatization (in-pipette-tip KF-SLE-ISD) method for simultaneous enrichment and derivatization of furfurals. Briefly, 3 mg of natural kapok fiber, which was loaded in an assembled pipette-tip, was used to support 12.5 µL of extractant (ethyl acetate/toluene, 75:25, v/v) containing 10 mM 2,4-dinitrophenylhydrazine. The in-pipette-tip KF-SLE-ISD procedure was conveniently conducted by aspirating/releasing 1 mL of sample solution 10 cycles, allowing simultaneous extraction and derivatization of furfurals. Then, 100 µL of acetonitrile was aspirated/released 5 cycles for elution, 10 µL of which was directly analyzed by high-performance liquid chromatography. The limits of quantitation were in ranges of 0.10-0.45 µg/mL. The method showed satisfied linearity (R2 > 0.99), precision (RSD < 8.53%) and relative recovery (90.34-114.71%), which was successfully applied to determine furfurals in various samples (e.g., honeys, juices and glucose injections). The proposed method has the merits of effectiveness, simplicity, low cost, wide availability and ease of automation.


Assuntos
Análise de Alimentos , Furaldeído , Cromatografia Líquida de Alta Pressão/métodos , Alimentos , Extração em Fase Sólida/métodos , Análise de Alimentos/métodos
9.
Talanta ; 253: 123982, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36206627

RESUMO

In this paper, a miniaturized kapok fiber-supported liquid extraction (mini-KF-SLE) method was proposed for selective extraction of pesticide residues in vegetable oils. The natural kapok fiber was used as an inert oil support material based on its hydrophobic and lipophilic properties, and the extraction device was conveniently constructed by loading 15 mg of kapok fiber at the lower middle part of a 1-mL pipette tip. The vegetable oil sample (150 mg) without any pretreatment was directly loaded, followed by the addition of 150 µL of acetonitrile (ACN) as the extractant. After static extraction for 30 min, the extractant was pipetted out with a pipettor. As the proof of concept, it was applied for extracting eight organochlorine pesticides (OCPs) from vegetable oils and the eluate was analyzed by gas chromatography-electron capture detector (GC-ECD). Under optimized conditions, the extraction recoveries of OCPs were calculated to be in ranges of 35.8-79.5%. The satisfied quantitation ability was verified by the established method with coefficients of determination (R2) being greater than 0.99. The limits of detection (LODs) were in ranges of 2.0-50.0 ng/g. The relative recoveries were in ranges of 78.3-117.0% with the inter-/intra-day relative standard deviation (RSD) both being less than 13.3%. The potential of mini-KF-SLE to extract other kinds of pesticides was further verified by the successful extracting three triazole pesticides in vegetable oils with good extraction recoveries (>41.4%). The proposed mini-KF-SLE in combination with instrument detection techniques has the great potential in the low-cost and high-throughput determination of various pesticide residues in vegetable oils.


Assuntos
Resíduos de Praguicidas , Óleos de Plantas
10.
J Chromatogr A ; 1681: 463480, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36095972

RESUMO

In this study, a novel kapok fiber-supported liquid extraction (KF-SLE) method was developed for conveniently extracting analytes from oil samples. Natural kapok fiber without any pretreatment was directly used as an oil support medium. The extraction device was conveniently constructed by directly packing some kapok fibers into a syringe tube. Due to the fibrous property of the kapok fiber, no filter plate was needed. The cost of a KF-SLE device was as low as 0.5 CNY. The KF-SLE process was conveniently conducted using a simple three-step protocol: (1) the oil sample without any pretreatment including dilution was added directedly; (2) then, the oil-immiscible extractant was added; (3) after waiting a certain time for static extraction, the extractant was eluted out by pressing the kapok fibers with the syringe plunger. The extractant could be directly transferred for subsequent instrumental detection. For the feasibility and proof-of-concept study, the method was applied to quantify four synthetic flavor chemicals in edible oils. Satisfied quantification results were obtained with the correlation coefficient (R2) being greater than 0.996, the relative recoveries ranging from 92.90% to 107.53% and intra- and inter-day RSDs being less than 7.56%. All in all, for the first time, the SLE technique was expanded to process oil samples and the method has the characteristics of low cost, environmental friendliness, high sample processing throughput and ease of automation, offering a promising approach for edible oil sample preparations.


Assuntos
Ceiba , Ceiba/química , Estudos de Viabilidade , Óleos/química , Manejo de Espécimes
11.
Sci Rep ; 12(1): 14690, 2022 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-36038626

RESUMO

The molecular mechanisms underlying circuit re-wiring in the mature brain remains ill-defined. An eloquent example of adult circuit remodelling is the hippocampal mossy fiber (MF) sprouting found in diseases such as temporal lobe epilepsy. The molecular determinants underlying this retrograde re-wiring remain unclear. This may involve signaling system(s) controlling axon specification/growth during neurodevelopment reactivated during epileptogenesis. Since adenosine A2A receptors (A2AR) control axon formation/outgrowth and synapse stabilization during development, we now examined the contribution of A2AR to MF sprouting. A2AR blockade significantly attenuated status epilepticus(SE)-induced MF sprouting in a rat pilocarpine model. This involves A2AR located in dentate granule cells since their knockdown selectively in dentate granule cells reduced MF sprouting, most likely through the ability of A2AR to induce the formation/outgrowth of abnormal secondary axons found in rat hippocampal neurons. These A2AR should be activated by extracellular ATP-derived adenosine since a similar prevention/attenuation of SE-induced hippocampal MF sprouting was observed in CD73 knockout mice. These findings demonstrate that A2AR contribute to epilepsy-related MF sprouting, most likely through the reactivation of the ability of A2AR to control axon formation/outgrowth observed during neurodevelopment. These results frame the CD73-A2AR axis as a regulator of circuit remodeling in the mature brain.


Assuntos
Adenosina , Epilepsia do Lobo Temporal , Receptor A2A de Adenosina/metabolismo , Animais , Epilepsia do Lobo Temporal/induzido quimicamente , Camundongos , Fibras Musgosas Hipocampais , Pilocarpina/farmacologia , Ratos , Sinapses/fisiologia
12.
J Chromatogr A ; 1678: 463361, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35914408

RESUMO

In this study, an on-tissue chemical labeling - matrix assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) method was developed for visualization of the distribution of three catecholamine (CA) compounds (dopamine, epinephrine and norepinephrine) in porcine adrenal gland. Commercially available pyrene-1-boronic acid (PBA) was employed as an effective in situ derivatizing reagent dissolved in acetonitrile containing 0.1% pyridine for the chemical labeling and the matrix coating. Without extra matrix coating, the tissue section was directly analyzed by MALDI-MS. The detection specificity and sensitivity were greatly improved with the on-tissue PBA labeling and successful imaging of the three CAs in porcine adrenal gland was achieved. Compared with previously reported methods for MALDI-MSI of the CAs, the analytical strategy proposed in the study provided a robust, easy-to-use and low-cost on-tissue chemical derivatization method that facilitated simultaneous molecular imaging of the three compounds.


Assuntos
Ácidos Borônicos , Catecolaminas , Glândulas Suprarrenais/química , Animais , Catecolaminas/análise , Pirenos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Suínos
13.
Molecules ; 27(9)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35566052

RESUMO

Catecholamines (CAs) and their metabolites play significant roles in many physiological processes. Changes in CAs concentration in vivo can serve as potential indicators for the diagnosis of several diseases such as pheochromocytoma and paraganglioma. Thus, the accurate quantification of CAs and their metabolites in biological samples is quite important and has attracted great research interest. However, due to their extremely low concentrations and numerous co-existing biological interferences, direct analysis of these endogenous compounds often suffers from severe difficulties. Employing suitable sample preparation techniques before instrument detection to enrich the target analytes and remove the interferences is a practicable and straightforward approach. To date, many sample preparation techniques such as solid-phase extraction (SPE), and liquid-liquid extraction (LLE) have been utilized to extract CAs and their metabolites from various biological samples. More recently, several modern techniques such as solid-phase microextraction (SPME), liquid-liquid microextraction (LLME), dispersive solid-phase extraction (DSPE), and chemical derivatizations have also been used with certain advanced features of automation and miniaturization. There are no review articles with the emphasis on sample preparations for the determination of catecholamine neurotransmitters in biological samples. Thus, this review aims to summarize recent progress and advances from 2015 to 2021, with emphasis on the sample preparation techniques combined with separation-based detection methods such capillary electrophoresis (CE) or liquid chromatography (LC) with various detectors. The current review manuscript would be helpful for the researchers with their research interests in diagnostic analysis and biological systems to choose suitable sample pretreatment and detection methods.


Assuntos
Neoplasias das Glândulas Suprarrenais , Microextração em Fase Líquida , Catecolaminas , Humanos , Microextração em Fase Líquida/métodos , Extração em Fase Sólida , Microextração em Fase Sólida/métodos
14.
J Chromatogr A ; 1673: 463081, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35489242

RESUMO

In the current study, natural cotton fiber was served as the supporter of water, and the water acted as an extractant for liquid-phase microextraction of polar components in low-polar edible oils. An in-syringe extraction device was constructed to facilitate the extraction process by simply loading a certain amount of cotton fibers between the syringe needle and the plastic syringe tube. Then, the extraction process can be conveniently conducted by pull-push the syringe plunger. It can be regarded as a new type of dynamic liquid-phase microextraction method while operated more convent. For the feasibility study, the novel in-syringe cotton fiber-supported liquid extraction (CF-SLECF-SLE) pretreatment method was applied to extract free 3-mono-chloropropane-1,2-diol (3-MCPD) in edible oils. Specifically, the cotton fibers supported a certain amount of water by successfully pulling-pushing 1 mL of water and 1 mL of HEX in/out twice, respectively. Then, 2.0 mL of diluted oil sample (containing 0.4 g oil) was loaded in and out four times for extraction, during which process 3-MCPD was extracted into the supported water. The extracted 3-MCPD was desorbed with 1 mL of ethyl acetate (EA), derivatized with trimethyl silane imidazole (TMSI), and analyzed by gas chromatography-tandem mass spectrometry (GC-MS/MS). For three different spiked edible oils, the internal standard normalized matrix effect (IS-normalized ME) values were in ranges of 96.3-104.8% with RSD being 4.3%, benefiting the accurate quantitative analysis. The limit of quantification (LOQ) was calculated to be 2 ng/g, which met the regular determination requirement of 3-MCPD in edible oils. Satisfied linearity was obtained in 2-500 ng/g, with correlation coefficients (R2) being 0.998. The relative recoveries were in the ranges of 96.9-110.5%. The intra-/inter-day RSDs were less than 8.2% and 10.2%, respectively. The proposed method provides an efficient, simple, low-cost, and easy to automate strategy for determining free 3-MCPD in edible oils.


Assuntos
alfa-Cloridrina , Fibra de Algodão , Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleos de Plantas/química , Seringas , Espectrometria de Massas em Tandem/métodos , Água , alfa-Cloridrina/análise
15.
Hum Brain Mapp ; 43(9): 2923-2935, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35289969

RESUMO

Aggression is a common and complex social behavior that is associated with violence and mental diseases. Although sex differences were observed in aggression, the neural mechanism for the effect of sex on aggression behaviors remains unclear, especially in specific subscales of aggression. In this study, we investigated the effects of sex on aggression subscales, gray matter volume (GMV), and functional connectivity (FC) of each insula subregion as well as the correlation of aggression subscales with GMV and FC. This study found that sex significantly influenced (a) physical aggression, anger, and hostility; (b) the GMV of all insula subregions; and (c) the FC of the dorsal agranular insula (dIa), dorsal dysgranular insula (dId), and ventral dysgranular and granular insula (vId_vIg). Additionally, mediation analysis revealed that the GMV of bilateral dIa mediates the association between sex and physical aggression, and left dId-left medial orbital superior frontal gyrus FC mediates the relationship between sex and anger. These findings revealed the neural mechanism underlying the sex differences in aggression subscales and the important role of the insula in aggression differences between males and females. This finding could potentially explain sexual dimorphism in neuropsychiatric disorders and improve dysregulated aggressive behavior.


Assuntos
Imageamento por Ressonância Magnética , Caracteres Sexuais , Agressão , Biomarcadores , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Masculino
16.
Epigenomics ; 14(22): 1411-1425, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36695107

RESUMO

Aim: To explore the effect of the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (Aza) on early renal injury. Materials & methods: Cell damage and inflammation are features of early renal injury. The apoptosis and inflammation in hypoxia/reoxygenation (H/R)-induced human proximal tubular epithelial cells (HK-2) and ischemia-reperfusion kidney were studied, and expression of the protein klotho was investigated. Results: Aza induced HK-2 apoptosis in a dose-dependent manner, but low-dose Aza attenuated the apoptosis and inflammation in H/R-induced HK-2 cells and ischemia-reperfusion kidney. Low-dose Aza ameliorated renal function in mice with renal ischemia-reperfusion injury. Meanwhile, low-dose Aza upregulated klotho expression in H/R-induced HK-2 cells and ischemia-reperfusion kidney. Klotho knockdown abrogated the effects of low-dose Aza on apoptosis and inflammation. Conclusion: Low-dose Aza protects against renal early injury by increasing klotho expression.


DNA methylation affects kidney disease and might be a clinically useful therapeutic target for kidney disease. It has been reported that blocking DNA methylation may reduce renal fibrosis. Early renal injury is a priming event of late renal function failure, and inhibition of early renal injury may be beneficial to prevent late loss of function. In this study, the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine was studied for its effects on cell apoptosis and inflammation in early renal injury. Low-dose 5-aza-2'-deoxycytidine had antiapoptotic and anti-inflammatory effects on HK-2 cells induced by hypoxia/reoxygenation and renal tissue with ischemia­reperfusion injury (IRI), and improved renal function following renal IRI. Possible mechanisms involved reduced methylation of klotho promoter DNA and upregulation of klotho expression. Therefore, it is attractive to speculate that preventing DNA methylation may be an effective strategy or method to attenuate renal early injury or renal IRI in human patients, as it is in rodents.


Assuntos
Apoptose , Rim , Humanos , Camundongos , Animais , Decitabina/farmacologia , Rim/metabolismo , Isquemia/metabolismo , Inflamação/metabolismo
17.
Neuroscience ; 478: 65-74, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655694

RESUMO

The mental rotation task is a particular spatial skill that helps people process visual information and is associated with intelligence and academic performance. Previous studies have found consistent sex difference in mental rotation. However, the neural mechanism of the sex-related difference in mental rotation remains unclear. This study investigates the association between sex, mental rotation and the functional connectivity (FC) of resting-state networks (RSNs) to explore neural correlates of different mental rotation abilities between males and females. Compared with females, males performed better on the mental rotation test. The mental rotation scores were significantly correlated with the special FC between the default mode network (DMN) and salience network (SN). The results of the mediation analysis revealed that the special FC between the DMN and SN mediated the association between sex and mental rotation. Based on these findings, males had higher FC between the DMN and SN, which subsequently promoted their mental rotation performance. These results emphasized the importance of sex in spatial cognition studies of both healthy people and individuals with neuropsychiatric disorders and deepened our understanding of the neural mechanisms underlying sex difference in mental rotation.


Assuntos
Mapeamento Encefálico , Caracteres Sexuais , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem
18.
Entropy (Basel) ; 23(9)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34573777

RESUMO

In this article, a novel adaptive fixed-time neural network tracking control scheme for nonlinear interconnected systems is proposed. An adaptive backstepping technique is used to address unknown system uncertainties in the fixed-time settings. Neural networks are used to identify the unknown uncertainties. The study shows that, under the proposed control scheme, each state in the system can converge into small regions near zero with fixed-time convergence time via Lyapunov stability analysis. Finally, the simulation example is presented to demonstrate the effectiveness of the proposed approach. A step-by-step procedure for engineers in industry process applications is proposed.

19.
Cereb Cortex ; 31(12): 5652-5663, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34184030

RESUMO

Cortical interneurons born in the subpallium reach the cortex through tangential migration, whereas pyramidal cells reach their final position by radial migration. Purinergic signaling via P2Y1 receptors controls the migration of intermediate precursor cells from the ventricular zone to the subventricular zone. It was also reported that the blockade of A2A receptors (A2AR) controls the tangential migration of somatostatin+ interneurons. Here we found that A2AR control radial migration of cortical projection neurons. In A2AR-knockout (KO) mouse embryos or naïve mouse embryos exposed to an A2AR antagonist, we observed an accumulation of early-born migrating neurons in the lower intermediate zone at late embryogenesis. In utero knockdown of A2AR also caused an accumulation of neurons at the lower intermediate zone before birth. This entails the presently identified ability of A2AR to promote multipolar-bipolar transition and axon formation, critical for the transition of migrating neurons from the intermediate zone to the cortical plate. This effect seems to require extracellular ATP-derived adenosine since a similar accumulation of neurons at the lower intermediate zone was observed in mice lacking ecto-5'-nucleotidase (CD73-KO). These findings frame adenosine as a fine-tune regulator of the wiring of cortical inhibitory and excitatory networks.


Assuntos
Neurônios , Receptor A2A de Adenosina , Animais , Axônios , Movimento Celular/fisiologia , Interneurônios , Camundongos , Neurônios/fisiologia , Células Piramidais/fisiologia , Receptor A2A de Adenosina/genética
20.
Sci Total Environ ; 734: 139394, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32485462

RESUMO

Freshwater consumption and wastewater discharge of economic activities have caused water scarcity problem in many regions. This study aims to develop a multi-dimensional diagnosis model (MDDM) to provide new insights for the sustainable development of regions which face water scarcity problem. In detail, the sectorial blue water, grey water and total water consumptions are assessed to reveal the direct effects of economic activities on water quantity and water quality. Then, hypothetical extraction method is integrated into input-output model and ecological network analysis to quantify the system-based effects of sectors in three dimensions: economy, water and metabolism. A case study of Guangdong province, China is conducted to illustrate the availability of the developed model. We found that the multi-dimensional performances of Guangdong's socioeconomic system are dominated by a few sectors. Wastewater, especially that discharged from the primary industry, is the main reason for the local water scarcity. Specifically, the unique role that every sector plays in the socioeconomic system is quantitatively revealed by MDDM, which could guide the relevant policy development at sectorial level.

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