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1.
Neuroimage ; 297: 120722, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38971483

RESUMO

Previous studies have shown that major depressive disorder (MDD) patients exhibit structural and functional impairments, but few studies have investigated changes in higher-order coupling between structure and function. Here, we systematically investigated the effect of MDD on higher-order coupling between structural connectivity (SC) and functional connectivity (FC). Each brain region was mapped into embedding vector by the node2vec algorithm. We used support vector machine (SVM) with the brain region embedding vector to distinguish MDD patients from health controls (HCs) and identify the most discriminative brain regions. Our study revealed that MDD patients had decreased higher-order coupling in connections between the most discriminative brain regions and local connections in rich-club organization and increased higher-order coupling in connections between the ventral attentional network and limbic network compared with HCs. Interestingly, transcriptome-neuroimaging association analysis demonstrated the correlations between regional rSC-FC coupling variations between MDD patients and HCs and α/ß-hydrolase domain-containing 6 (ABHD6), ß 1,3-N-acetylglucosaminyltransferase-9(ß3GNT9), transmembrane protein 45B (TMEM45B), the correlation between regional dSC-FC coupling variations and retinoic acid early transcript 1E antisense RNA 1(RAET1E-AS1), and the correlations between regional iSC-FC coupling variations and ABHD6, ß3GNT9, katanin-like 2 protein (KATNAL2). In addition, correlation analysis with neurotransmitter receptor/transporter maps found that the rSC-FC and iSC-FC coupling variations were both correlated with neuroendocrine transporter (NET) expression, and the dSC-FC coupling variations were correlated with metabotropic glutamate receptor 5 (mGluR5). Further mediation analysis explored the relationship between genes, neurotransmitter receptor/transporter and MDD related higher-order coupling variations. These findings indicate that specific genetic and molecular factors underpin the observed disparities in higher-order SC-FC coupling between MDD patients and HCs. Our study confirmed that higher-order coupling between SC and FC plays an important role in diagnosing MDD. The identification of new biological evidence for MDD etiology holds promise for the development of innovative antidepressant therapies.

2.
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
3.
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.

4.
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
5.
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
6.
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
7.
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.

8.
Mol Ther ; 27(5): 1051-1065, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-30853453

RESUMO

Renal fibrosis is the main pathological characteristic of chronic kidney disease (CKD), whereas the underlying mechanisms of renal fibrosis are not clear yet. Herein, we found an increased expression of microRNA-34a (miR-34a) in renal tubular epithelial cells of patients with renal fibrosis and mice undergoing unilateral ureteral obstruction (UUO). In miR-34a-/- mice, miR-34a deficiency attenuated the progression of renal fibrosis following UUO surgery. The miR-34a overexpression promoted epithelial-to-mesenchymal transition (EMT) in cultured human renal tubular epithelial HK-2 cells, which was accompanied by sharp downregulation of Klotho, an endogenous inhibitor of renal fibrosis. Luciferase reporter assay revealed that miR-34a downregulated Klotho expression though direct binding with the 3' UTR of Klotho. Conversely, overexpression of Klotho prevented miR-34a-induced EMT in HK-2 cells. Furthermore, results showed that miR-34a was induced by transforming growth factor ß1 (TGF-ß1) through p53 activation, whereas dihydromyricetin could inhibit TGF-ß1-induced miR-34a overexpression. Accordingly, dihydromyricetin administration dramatically restored the aberrant upregulation of miR-34a and Klotho reduction in obstructed kidney, and markedly ameliorated renal fibrosis in the Adriamycin nephropathy and UUO model mice. These findings suggested that miR-34a plays an important role in the progression of renal fibrosis, which provides new insights into the pathogenesis and treatment of CKD.


Assuntos
Fibrose/tratamento farmacológico , Glucuronidase/genética , Nefropatias/tratamento farmacológico , MicroRNAs/genética , Fator de Crescimento Transformador beta1/genética , Animais , Linhagem Celular , Modelos Animais de Doenças , Doxorrubicina/toxicidade , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fibrose/induzido quimicamente , Fibrose/genética , Fibrose/patologia , Flavonóis/farmacologia , Glucuronidase/antagonistas & inibidores , Humanos , Rim/efeitos dos fármacos , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/genética , Nefropatias/patologia , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Proteínas Klotho , Camundongos , MicroRNAs/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Obstrução Ureteral/induzido quimicamente , Obstrução Ureteral/tratamento farmacológico , Obstrução Ureteral/genética , Obstrução Ureteral/patologia
9.
Am J Nephrol ; 46(4): 333-342, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29017152

RESUMO

BACKGROUND: Hyperuricemia is an independent risk factor for causing chronic kidney disease and contributes to kidney fibrosis. After urate crystals get deposited in the kidney, they can cause hyperuricemia nephropathy, leading to glomerular hypertrophy and renal tubular interstitial fibrosis. Recent data showed that uric acid (UA) could induce epithelial mesenchymal transition (EMT) of renal tubular cells, in which NRLP3 inflammatory pathway was involved. However, whether TLR4/NF-κB signaling pathway is also involved in EMT of renal tubular cells induced by UA is not clear. METHODS: Human renal tubular epithelial cells (HK-2) were directly treated with UA and the phenotypic transition was detected by morphological changes and the molecular markers of EMT. The activation of the TLR4/NF-κB signaling pathway induced by UA was measured by Western blot and its involvement was further confirmed by the inhibition of NF-κB activation or knockdown of toll like receptor 4 (TLR4) expression. RESULTS: UA induced obvious morphological changes of HK-2 cell, accompanied with altered molecular markers of EMT including fibronectin, α-SMA and E-cadherin. In addition, UA significantly upregulated the gene expression of interleukin-1ß and tumor necrosis factor-α in a time- and dose-dependent manner. Furthermore, UA significantly activated the TLR4/NF-κB signaling pathway in HK-2 cells, while the inhibition of the TLR4 expression by siRNA and NF-κB activation by PDTC significantly attenuated EMT induced by UA in HK-2 cells. CONCLUSIONS: UA can induce EMT in renal tubular epithelial cells by the activation of the TLR4/NF-κB signaling pathway, and the targeted intervention of the TLR4/NF-κB signaling pathway might effectively inhibit UA-induced renal interstitial fibrosis mediated by EMT.


Assuntos
Transição Epitelial-Mesenquimal , NF-kappa B/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Ácido Úrico/metabolismo , Actinas/metabolismo , Antígenos CD , Biomarcadores/metabolismo , Caderinas/metabolismo , Linhagem Celular , Citocinas/metabolismo , Células Epiteliais/metabolismo , Fibronectinas , Humanos , Hiperuricemia/complicações , Hiperuricemia/metabolismo , Hiperuricemia/fisiopatologia , Interleucina-1beta/metabolismo , Túbulos Renais/citologia , Terapia de Alvo Molecular/métodos , NF-kappa B/antagonistas & inibidores , Nefrite Intersticial/tratamento farmacológico , Nefrite Intersticial/etiologia , Pirrolidinas/farmacologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Tiocarbamatos/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
10.
Kidney Blood Press Res ; 42(6): 1205-1215, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29227975

RESUMO

BACKGROUND/AIMS: Hyperphosphatemia is one of the most notable features of chronic kidney disease (CKD). Numerous epidemiological and clinical studies have found that high serum phosphate concentrations are associated with calcification in the coronary arteries. However, the mechanisms underlying the vascular calcification induced by high phosphate have not been understood fully. METHODS: Vascular smooth muscle cells (VSMCs) were cultured in high-phosphate media to induce vascular calcification, which was detected by Alizarin red S staining. Gene expression and protein levels of differentiation markers were determined by real-time RT-PCR and western blotting, respectively. Protein levels of phosphorylated NF-κB and TLR4 were detected by western blotting, and the role of NF-κB/TLR4 was further confirmed by using an NF-κB inhibitor or TLR4 siRNA. RESULTS: Our results showed that high-phosphate media induced obvious calcification of VSMCs. Simultaneously, VSMC differentiation was confirmed by the increased expression of bone morphogenetic protein-2 and Runt-related transcription factor 2 and decreased expression of the VSMC-specific marker SM22α, which was accompanied by the increased expression of inflammatory cytokines. Moreover, a significant upregulation of TLR4 and phosphorylated NF-κB was also detected in VSMCs with high-phosphate media. In contrast, VSMC calcification and the increased expression of inflammatory cytokines were markedly attenuated by pretreatment with TLR4 siRNA and pyrrolidine dithiocarbamic acid, an NF-κB inhibitor. CONCLUSION: These data suggest that high-phosphate conditions directly induce vascular calcification via the activation of TLR4/NF-κB signaling in VSMCs. Moreover, inhibition of the TLR4/NF-κB signaling pathway might be a key intervention to prevent vascular calcification in patients with CKD.


Assuntos
Músculo Liso Vascular/metabolismo , Fosfatos/química , Fosfatos/farmacologia , Calcificação Vascular/induzido quimicamente , Células Cultivadas , Humanos , Hiperfosfatemia/complicações , NF-kappa B/metabolismo , Insuficiência Renal Crônica/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo
11.
J Am Soc Nephrol ; 26(10): 2434-46, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25804281

RESUMO

Left ventricular hypertrophy (LVH) is a common complication in patients with CKD and an independent risk factor for death. Changes in the levels of uremic solutes or Klotho have been reported to be related to CKD, whereas the relationships between these factors and CKD-associated LVH remain unclear. Here, we investigated the interaction between Klotho and indoxyl sulfate (IS), a typical uremic solute, in CKD-associated LVH. In a survey of 86 patients with CKD, a negative relationship was found between serum levels of IS and Klotho (r=-0.59, P<0.001). Furthermore, serum levels of IS and Klotho were independently associated with LVH (for IS: r=0.69, P<0.001; for Klotho: r=-0.49, P<0.001). In normal mice, intraperitoneal injection of IS for 8 weeks induced LVH accompanied by substantial downregulation of renal Klotho. Notably, IS-induced LVH was more severe in heterozygous Klotho-deficient (kl/+) mice. In vitro, treatment with Klotho strongly inhibited IS-induced cardiomyocyte hypertrophy by blocking oxidative stress and inhibiting p38 and extracellular signal-regulated protein kinase 1/2 signaling pathways. In a mouse model of CKD-associated LVH, the renal expression of Klotho was lower and the level of serum IS was higher than in healthy controls. Moreover, treatment of CKD mice with Klotho protein significantly restrained the development of LVH. Taken together, these results suggest that Klotho is an endogenous protector against IS-induced LVH, and the imbalance between Klotho and IS may contribute to the development of LVH in CKD.


Assuntos
Glucuronidase/fisiologia , Hipertrofia Ventricular Esquerda/etiologia , Indicã/fisiologia , Insuficiência Renal Crônica/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Glucuronidase/sangue , Glucuronidase/uso terapêutico , Humanos , Hipertrofia Ventricular Esquerda/sangue , Hipertrofia Ventricular Esquerda/induzido quimicamente , Hipertrofia Ventricular Esquerda/prevenção & controle , Indicã/administração & dosagem , Indicã/sangue , Proteínas Klotho , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Insuficiência Renal Crônica/sangue , Adulto Jovem
12.
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
13.
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
14.
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
15.
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
16.
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
17.
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
18.
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
19.
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
20.
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
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