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1.
Liver Int ; 44(2): 293-315, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38110988

RESUMEN

O-GlcNAcylation is a dynamic, reversible and atypical O-glycosylation that regulates various cellular physiological processes via conformation, stabilisation, localisation, chaperone interaction or activity of target proteins. The O-GlcNAcylation cycle is precisely controlled by collaboration between O-GlcNAc transferase and O-GlcNAcase. Uridine-diphosphate-N-acetylglucosamine, the sole donor of O-GlcNAcylation produced by the hexosamine biosynthesis pathway, is controlled by the input of glucose, glutamine, acetyl coenzyme A and uridine triphosphate, making it a sensor of the fluctuation of molecules, making O-GlcNAcylation a pivotal nutrient sensor for the metabolism of carbohydrates, amino acids, lipids and nucleotides. O-GlcNAcylation, particularly prevalent in liver, is the core hub for controlling systemic glucose homeostasis due to its nutritional sensitivity and precise spatiotemporal regulation of insulin signal transduction. The pathology of various liver diseases has highlighted hepatic metabolic disorder and dysfunction, and abnormal O-GlcNAcylation also plays a specific pathological role in these processes. Therefore, this review describes the unique features of O-GlcNAcylation and its dynamic homeostasis maintenance. Additionally, it explains the underlying nutritional sensitivity of O-GlcNAcylation and discusses its mechanism of spatiotemporal modulation of insulin signal transduction and liver metabolic homeostasis during the fasting and feeding cycle. This review emphasises the pathophysiological implications of O-GlcNAcylation in nonalcoholic fatty liver disease, nonalcoholic steatohepatitis and hepatic fibrosis, and focuses on the adverse effects of hyper O-GlcNAcylation on liver cancer progression and metabolic reprogramming.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Transducción de Señal , Humanos , Glicosilación , Procesamiento Proteico-Postraduccional , Insulina , Glucosa
2.
Childs Nerv Syst ; 40(2): 549-553, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37552306

RESUMEN

Angiolipomas are slow-growing benign mesenchymal-derived tumors consisting of mature adipocytes and thin-walled blood vessels. While the majority of angiolipomas are found in subcutaneous tissues, rarely there are case reports of intracranial lesions. We present a case of cisternal angiolipoma in a 10-year-old female. She presented with vague symptoms like dizziness without neurological deficits and radiological evaluation confirmed a left-sided infratentorial cisternal partially enhancing mass. She underwent craniotomy and had complete resection of the mass, which was histologically composed of mature adipocytes and blood vessels, consistent with angiolipoma. A review of the literature found only 18 cases of intracranial angiolipoma ever reported with our case representing the first case of infratentorial cisternal region.


Asunto(s)
Angiolipoma , Femenino , Humanos , Niño , Angiolipoma/diagnóstico por imagen , Angiolipoma/cirugía , Radiografía , Tejido Subcutáneo/patología , Tejido Subcutáneo/cirugía , Craneotomía
3.
Curr Issues Mol Biol ; 45(12): 9868-9886, 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38132462

RESUMEN

Lung ischemia-reperfusion injury (LIRI) is a prevalent occurrence in various pulmonary diseases and surgical procedures, including lung resections and transplantation. LIRI can result in systemic hypoxemia and multi-organ failure. Hydroxycitric acid (HCA), the primary acid present in the peel of Garcinia cambogia, exhibits anti-inflammatory, antioxidant, and anticancer properties. However, the effects of HCA on LIRI remain unknown. To investigate the impact of HCA on LIRI in mice, the mice were randomly divided into four groups: the control group, the I/R model group, and the I/R + low- or high-dose HCA groups. Human umbilical vein endothelial cells (HUVECs) were subjected to hypoxia for 12 h followed by reoxygenation for 6 h to simulate in vitro LIRI. The results demonstrated that administration of HCA effectively attenuated lung injury, inflammation, and edema induced by ischemia reperfusion. Moreover, HCA treatment significantly reduced malondialdehyde (MDA) and reactive oxygen species (ROS) levels while decreasing iron content and increasing superoxide dismutase (SOD) levels after ischemia-reperfusion insult. Mechanistically, HCA administration significantly inhibited Hif-1α and HO-1 upregulation both in vivo and in vitro. We found that HCA could also alleviate endothelial barrier damage in H/R-induced HUVECs in a concentration-dependent manner. In addition, overexpression of Hif-1α counteracted HCA-mediated inhibition of H/R-induced endothelial cell ferroptosis. In summary, these results indicate that HCA alleviated LIRI by inhibiting oxidative stress and ferroptosis through the Hif-1α pathway.

4.
Mol Ther ; 30(3): 1252-1264, 2022 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-34999209

RESUMEN

Endothelial tip cell specialization plays an essential role in angiogenesis, which is tightly regulated by the complicated gene regulatory network. Circular RNA (circRNA) is a type of covalently closed non-coding RNA that regulates gene expression in eukaryotes. Here, we report that the levels of circMET expression are significantly upregulated in the retinas of mice with oxygen-induced retinopathy, choroidal neovascularization, and diabetic retinopathy. circMET silencing significantly reduces pathological angiogenesis and inhibits tip cell specialization in vivo. circMET silencing also decreases endothelial migration and sprouting in vitro. Mechanistically, circMET regulates endothelial sprouting and pathological angiogenesis by acting as a scaffold to enhance the interaction between IGF2BP2 and NRARP/ESM1. Clinically, circMET is significantly upregulated in the clinical samples of the patients of diabetic retinopathy. circMET silencing could reduce diabetic vitreous-induced endothelial sprouting and retinal angiogenesis in vivo. Collectively, these data identify a circRNA-mediated mechanism that coordinates tip cell specialization and pathological angiogenesis. circMET silencing is an exploitable therapeutic approach for the treatment of neovascular diseases.


Asunto(s)
Neovascularización Coroidal , Retinopatía Diabética , Animales , Neovascularización Coroidal/genética , Retinopatía Diabética/tratamiento farmacológico , Retinopatía Diabética/genética , Células Endoteliales/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , ARN Circular/genética , Proteínas de Unión al ARN/metabolismo , Retina/metabolismo
5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(3): 510-516, 2023 May.
Artículo en Zh | MEDLINE | ID: mdl-37248576

RESUMEN

Objective: To investigate the effect of oral squamous cell carcinoma (OSCC)-derived cell-free DNA (cfDNA) on the polarization of macrophages and the regulatory effect of polarized macrophages on the stemness and migration of OSCC cells. Methods: A total of 30 OSCC tissue samples, 10 dysplastic oral tissue samples, and 10 normal oral tissue samples were collected. The status of all tissue samples was confirmed by pathology analysis. Immunohistochemical (IHC) staining and immunofluorescence (IF) staining were performed to examine the cell count and location of M2 macrophages in different types of oral tissue samples. The conditioned medium (CM) of OSCC cell line CAL-27 from the human tongue was collected and the cfDNA was concentrated and isolated for identification. The macrophages were treated by cfDNA and their morphological characteristics were observed under microscope. The expression levels of polarization-related indicators were determined by RT-qPCR. CAL-27 cell line was treated with macrophage CM induced by cfDNA and the expression levels of stemness-related genes were determined by RT-qPCR. Scratch-wound assay was conducted to verify that the migration ability of CAL-27 was modulated by macrophages induced by cfDNA. Results: There were more M2 macrophages in the deep connective tissue of dysplastic oral epithelium and the stroma of OSCC compared with those in the normal oral tissues ( P<0.05). OSCC cell line CAL-27 could secret cfDNA of 10000-15000 bp in length. cfDNA secreted by CAL-27 could induced in macrophages significantly higher expression of M2-macrophage-related genes ( P<0.05). cfDNA-treated macrophages induced significantly increased expression of stemness-related genes in CAL-27 cell line ( P<0.05) and promoted the migration ability of CAL-27 cell line ( P<0.05). Conclusion: OSCC-derived cfDNA promotes stemness and migration of OSCC cell line by inducing M2 macrophage polarization.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Neoplasias de la Boca/genética , Macrófagos/metabolismo , Línea Celular , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/patología , Línea Celular Tumoral , Proliferación Celular , Movimiento Celular
6.
Angew Chem Int Ed Engl ; 62(20): e202214322, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-36696269

RESUMEN

The development of facile methodologies to afford robust supported metal nanocatalysts under mild conditions is highly desirable yet challenging, particularly via strong metal-support interactions (SMSI) construction. State-of-the-art approaches capable of generating SMSI encapsulation mainly focus on high temperature annealing in reductive/oxidative atmosphere. Herein, ultra-stable metal nanocatalysts based on SMSI construction were produced by leveraging the instantaneous high-energy input from ultrasonication under ambient conditions in H2 O, which could rapidly afford abundant active intermediates, Ti3+ ions, and oxygen vacancies within the scaffolds to induce the SMSI overlayer formation. The encapsulation degree could be tuned and controlled via the reducibility of the solvents and the ultrasonication parameters. This facile and efficient approach could be further extended to diverse metal oxide supports and noble metal NPs leading to enhanced performance in hydrogenation reactions and CO2 conversion.

7.
Biochem Biophys Res Commun ; 587: 99-106, 2022 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-34872005

RESUMEN

Colorectal cancer (CRC) is one of the most common malignant tumors in the digestive system, and Chinese herbal medicine plays an important role in tumor treatment. The in-depth study of auriculasin isolated from Flemingia philippinensis showed that auriculasin promoted reactive oxygen species (ROS) generation in a concentration-dependent manner; when ROS scavenger NAC was added, the effects of auriculasin in promoting ROS generation and inhibiting cell viability were blocked. Auriculasin induced CRC cell apoptosis, led to mitochondrial shrinkage, and increased the intracellular accumulation of Fe2+ and MDA. When auriculasin and NAC were added simultaneously, the levels of apoptosis, Fe2+ and MDA returned to the control group levels, indicating that auriculasin activated apoptosis and ferroptosis by inducing ROS generation. In addition, auriculasin promoted the expression of Keap1 and AIFM1, but significantly reduced the phosphorylation level of AIFM1, while NAC significantly blocked the regulation of Keap1 and AIFM1 by auriculasin, which indicates that auriculasin can also induce oxeiptosis through ROS. When Z-VAD-FMK, Ferrostatin-1, Keap1 siRNA, PGAM5 siRNA and AIFM1 siRNA were added respectively, the inhibitory effect of auriculasin on cell viability was significantly weakened, indicating that auriculasin inhibits cell viability by inducing apoptosis, ferroptosis and oxeiptosis. Auriculasin also inhibited the invasion and clone forming ability of CRC cells, while NAC blocked the above effects of auriculasin. Therefore, auriculasin can promote CRC cell apoptosis, ferroptosis and oxeiptosis by inducing ROS generation, thereby inhibiting cell viability, invasion and clone formation, indicating that auriculasin has a significant antitumor effect.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Ferroptosis/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Isoflavonas/farmacología , Especies Reactivas de Oxígeno/agonistas , Antineoplásicos Fitogénicos/aislamiento & purificación , Apoptosis/genética , Factor Inductor de la Apoptosis/genética , Factor Inductor de la Apoptosis/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Fabaceae/química , Ferroptosis/genética , Células HCT116 , Humanos , Hierro/agonistas , Hierro/metabolismo , Isoflavonas/aislamiento & purificación , Proteína 1 Asociada A ECH Tipo Kelch/genética , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Malondialdehído/agonistas , Malondialdehído/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/patología , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Modelos Biológicos , Fosfoproteínas Fosfatasas/genética , Fosfoproteínas Fosfatasas/metabolismo , Extractos Vegetales/química , Especies Reactivas de Oxígeno/metabolismo
8.
J Nat Prod ; 85(8): 2110-2115, 2022 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-35969376

RESUMEN

The structural revision of four Stemona alkaloids from Stemona tuberosa is reported. The misassignment of the tuberostemonine O structure (1) was recognized when a new alkaloid, tuberostemonine P, was isolated and unambiguously assigned structure 1 in this work. Reinvestigation of the spectroscopic data and NMR calculations led to the revised structure 1a for tuberostemonine O. The structural misassignment of dehydrocroomine A as 2 was corrected by reinterpreting the X-ray crystal structure, which was consistent with 2a. The structural reassignments of dehydrocroomine B (3 to 3a) and dehydrocroomine (4 to 4a) were confirmed by X-ray crystallography and NMR calculations, respectively.


Asunto(s)
Alcaloides , Stemonaceae , Alcaloides/química , Estructura Molecular , Stemonaceae/química
9.
Neoplasma ; 69(6): 1480-1489, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36591802

RESUMEN

The clinical data of stage I invasive lung adenocarcinoma patients with spread through air spaces (STAS) who underwent lobectomy from January 1, 2013 to January 1, 2016 at the Department of Thoracic Surgery of Hebei Medical University were analyzed retrospectively, and statistical analysis was carried out to explore their clinical features and prognostic value of EGFR mutation. A total of 280 patients were included in the study cohort, and EGFR mutations were detected in 154 patients. EGFR mutations were more common in non-smokers (p=0.045), females (p<0.001), without vascular tumor thrombus (p=0.037), and histological subtype LPA/APA/PPA (p=0.001). Multivariate analysis of the Cox risk regression model showed that EGFR gene mutation (p=0.807) was not an independent influencing factor of recurrence-free survival (RFS), but EGFR mutation was an independent influencing factor of overall survival (OS) (p=0.012), and OS of patients with EGFR mutation was better. The EGFR mutation also significantly increased the progression-free survival (PFS) of relapsed patients (p<0.001), but the PFS of relapsed EGFR mutation patients who received adjuvant chemotherapy after the operation was worse than that of patients who did not receive adjuvant chemotherapy (p=0.029). EGFR gene mutation is not a risk factor for postoperative recurrence in patients with stage I lung adenocarcinoma with STAS but the 5-year survival rate of patients with EGFR gene mutation is better than that of wild-type. Postoperative adjuvant chemotherapy for patients with EGFR mutation should be carefully considered.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Femenino , Humanos , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/cirugía , Adenocarcinoma del Pulmón/patología , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/cirugía , Mutación , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Alveolos Pulmonares/patología , Masculino
10.
Nucleic Acids Res ; 48(2): 548-560, 2020 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-31799631

RESUMEN

Achieving rapid, noninvasive actuation of DNA structures is critical to expanding the functionality of DNA nanotechnology. A promising actuation approach involves introducing multiple, short pairs of single-stranded DNA overhangs to components of the structure and triggering hybridization or dissociation of the overhangs via changes in solution ionic conditions to drive structural transitions. Here, we reveal the underlying basis of this new approach by computing via molecular simulations the free energy landscape of DNA origami hinges actuated between open and closed states. Our results reveal how the overhangs collectively introduce a sharp free-energy minimum at the closed state and a broad energy barrier between open and closed states and how changes in ionic conditions modulate these features of the landscape to drive actuation towards the open or closed state. We demonstrate the critical role played by hinge confinement in stabilizing the hybridized state of the overhangs and magnifying the energy barrier to dissociation. By analyzing how the distribution of overhangs and their length and sequence modulate the energy landscape, we obtain design rules for tuning the actuation behavior. The molecular insights obtained here should be applicable to a broad range of systems involving DNA hybridization within confined systems.


Asunto(s)
ADN de Cadena Simple/química , ADN/química , Nanotecnología , Termodinámica , Simulación por Computador , ADN/genética , ADN de Cadena Simple/genética , Entropía , Nanoestructuras/química , Conformación de Ácido Nucleico , Sales (Química)/química , Sales (Química)/farmacología , Cloruro de Sodio/química , Cloruro de Sodio/farmacología
11.
J Am Chem Soc ; 143(23): 8521-8526, 2021 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-34081447

RESUMEN

Strong metal-support interaction (SMSI) construction is a pivotal strategy to afford thermally robust nanocatalysts in industrial catalysis, but thermally induced reactions (>300 °C) in specific gaseous atmospheres are generally required in traditional procedures. In this work, a photochemistry-driven methodology was demonstrated for SMSI construction under ambient conditions. Encapsulation of Pd nanoparticles with a TiOx overlayer, the presence of Ti3+ species, and suppression of CO adsorption were achieved upon UV irradiation. The key lies in the generation of separated photoinduced reductive electrons (e-) and oxidative holes (h+), which subsequently trigger the formation of Ti3+ species/oxygen vacancies (Ov) and then interfacial Pd-Ov-Ti3+ sites, affording a Pd/TiO2 SMSI with enhanced catalytic hydrogenation efficiency. The as-constructed SMSI layer was reversible, and the photodriven procedure could be extended to Pd/ZnO and Pt/TiO2.

12.
Mol Med ; 27(1): 141, 2021 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-34732133

RESUMEN

BACKGROUND: We aimed to investigate the functions and underlying mechanism of lncRNA SNHG1 in bone differentiation and angiogenesis in the development of osteoporosis. METHODS: The differential gene or proteins expressions were measured by qPCR or western blot assays, respectively. The targeted relationships among molecular were confirmed through luciferase reporter, RIP and ChIP assays, respectively. Alkaline phosphatase (ALP), alizarin red S (ARS) and TRAP staining were performed to measure the osteoblast/osteoclast differentiation of BMSCs. The viability, migration and angiogenesis in BM-EPCs were validated by CCK-8, clone formation, transwell and tube formation assays, respectively. Western blot and immunofluorescence detected the cytosolic/nuclear localization of ß-catenin. Ovariectomized (OVX) mice were established to confirm the findings in vitro. RESULTS: SNHG1 was enhanced and miR-181c-5p was decreased in serum and femoral tissue from OVX mice. SNHG1 directly inhibited miR-181c-5p to activate Wnt3a/ß-catenin signaling by upregulating SFRP1. In addition, knockdown of SNHG1 promoted the osteogenic differentiation of BMSCs by increasing miR-181c-5p. In contrast, SNHG1 overexpression advanced the osteoclast differentiation of BMSCs and inhibited the angiogenesis of BM-EPCs, whereas these effects were all reversed by miR-181c-5p overexpression. In vivo experiments indicated that SNHG1 silencing alleviated osteoporosis through stimulating osteoblastogenesis and inhibiting osteoclastogenesis by modulating miR-181c-5p. Importantly, SNHG1 could be induced by SP1 in BMSCs. CONCLUSIONS: Collectively, SP1-induced SNHG1 modulated SFRP1/Wnt/ß-catenin signaling pathway via sponging miR-181c-5p, thereby inhibiting osteoblast differentiation and angiogenesis while promoting osteoclast formation. Further, SNHG1 silence might provide a potential treatment for osteoporosis.


Asunto(s)
Remodelación Ósea/genética , MicroARNs , Osteoporosis/genética , ARN Largo no Codificante , Factor de Transcripción Sp1/genética , Animales , Diferenciación Celular , Células Cultivadas , Femenino , Proteínas de la Membrana/metabolismo , Ratones Endogámicos C57BL , Neovascularización Fisiológica , Transducción de Señal , Células Madre/citología , Proteína Wnt3A/metabolismo
13.
Small ; 17(16): e2004579, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33464724

RESUMEN

The development of novel single atom catalyst (SAC) is highly desirable in organic synthesis to achieve the maximized atomic efficiency. Here, a Co-based SAC on nitrogen-doped graphene (SACo@NG) with high Co content of 4.1 wt% is reported. Various characterization results suggest that the monodispersed Co atoms are coordinated with N atoms to form robust and highly effective catalytic centers to activate peroxymonosulfate (PMS) for organic selective oxidation. The catalytic performance of the SACo@NG/PMS system is conducted on the selective oxidation of benzyl alcohol (BzOH) showing high efficiency with over 90% conversion and benzaldehyde selectivity within 180 min under mild conditions. Both radical and non-radical processes occurred in the selective oxidation of BzOH, but the non-radical oxidation plays the dominant role which is accomplished by the adsorption of BzOH/PMS on the surface of SACo@NG and the subsequent electron transfer through the carbon matrix. This work provides new insights to the preparation of efficient transition metal-based single atom catalysts and their potential applications in PMS mediated selective oxidation of alcohols.

14.
Sensors (Basel) ; 21(9)2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-34067100

RESUMEN

The supervised model based on deep learning has made great achievements in the field of image classification after training with a large number of labeled samples. However, there are many categories without or only with a few labeled training samples in practice, and some categories even have no training samples at all. The proposed zero-shot learning greatly reduces the dependence on labeled training samples for image classification models. Nevertheless, there are limitations in learning the similarity of visual features and semantic features with a predefined fixed metric (e.g., as Euclidean distance), as well as the problem of semantic gap in the mapping process. To address these problems, a new zero-shot image classification method based on an end-to-end learnable deep metric is proposed in this paper. First, the common space embedding is adopted to map the visual features and semantic features into a common space. Second, an end-to-end learnable deep metric, that is, the relation network is utilized to learn the similarity of visual features and semantic features. Finally, the invisible images are classified, according to the similarity score. Extensive experiments are carried out on four datasets and the results indicate the effectiveness of the proposed method.

15.
Nano Lett ; 20(2): 1252-1261, 2020 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-31887051

RESUMEN

Lithium-sulfur (Li-S) batteries are promising next-generation energy storage technologies due to their high theoretical energy density, environmental friendliness, and low cost. However, low conductivity of sulfur species, dissolution of polysulfides, poor conversion from sulfur reduction, and lithium sulfide (Li2S) oxidation reactions during discharge-charge processes hinder their practical applications. Herein, under the guidance of density functional theory calculations, we have successfully synthesized large-scale single atom vanadium catalysts seeded on graphene to achieve high sulfur content (80 wt % sulfur), fast kinetic (a capacity of 645 mAh g-1 at 3 C rate), and long-life Li-S batteries. Both forward (sulfur reduction) and reverse reactions (Li2S oxidation) are significantly improved by the single atom catalysts. This finding is confirmed by experimental results and consistent with theoretical calculations. The ability of single metal atoms to effectively trap the dissolved lithium polysulfides (LiPSs) and catalytically convert the LiPSs/Li2S during cycling significantly improved sulfur utilization, rate capability, and cycling life. Our work demonstrates an efficient design pathway for single atom catalysts and provides solutions for the development of high energy/power density Li-S batteries.

16.
Sheng Li Xue Bao ; 73(4): 617-630, 2021 Aug 25.
Artículo en Zh | MEDLINE | ID: mdl-34405218

RESUMEN

The morbidity and mortality of cardiovascular diseases are increasing annually, which is one of the primary causes of human death. Recent studies have shown that epoxyeicosatrienoic acids (EETs), endogenous metabolites of arachidonic acid (AA) via CYP450 epoxygenase, possess a spectrum of protective properties in cardiovascular system. EETs not only alleviate cardiac remodeling and injury in different pathological models, but also improve subsequent hemodynamic disturbances and cardiac dysfunction. Meanwhile, various studies have demonstrated that EETs, as endothelial-derived hyperpolarizing factors, regulate vascular tone by activating various ion channels on endothelium and smooth muscle, which in turn can lower blood pressure, improve coronary blood flow and regulate pulmonary artery pressure. In addition, EETs are protective in endothelium, including inhibiting inflammation and adhesion of endothelial cells, attenuating platelet aggregation, promoting fibrinolysis and revascularization. EETs can also prevent aortic remodeling, including attenuating atherosclerosis, adventitial remodeling, and aortic calcification. Therefore, it is clinically important to study the physiological and pathophysiological effects of EETs in the cardiovascular system to further elucidate the mechanisms, as well as provide new strategy for the prevention and treatment of cardiovascular diseases. This review summarizes the endogenous cardioprotective effects and mechanisms of EETs in order to provide a new insight for research in this field.


Asunto(s)
Sistema Cardiovascular , Células Endoteliales , Ácido 8,11,14-Eicosatrienoico/farmacología , Citocromo P-450 CYP2J2 , Sistema Enzimático del Citocromo P-450 , Eicosanoides , Humanos
17.
J Anim Physiol Anim Nutr (Berl) ; 104(6): 1948-1959, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32090391

RESUMEN

miRNAs are a class of small non-coding RNAs that are involved in various biological processes. In the preliminary work of the laboratory, found that miR-383-5p was down-regulated in the liver tissue of acute cold stress rats and has been shown to be an important regulatory factor in tumour proliferation, but there are very few studies involving the mediation of cold stress in rat liver tissues. Therefore, the purpose of this study was to determine the effect of miR-383-5p on the livers of cold stress rats by simulating the cold stress state of rat liver tissues in vitro using H2 O2 to induce rat hepatocyte oxidative stress. The results showed that MDA content, Caspase 3 and Cyto C protein levels increased significantly; GPx activity and SOD1 protein levels decreased significantly and miR-383-5p expression was significantly down-regulated in rat liver tissues after cold stress. Different concentrations of H2 O2 was added to rat hepatocytes, and the results showed that the expression of miR-383-5p, the ROS level, and the apoptosis rate in rat hepatocytes was increased significantly in a concentration-dependent fashion. Transfection of miR-383-5p inhibitor revealed that the apoptosis rate of rat hepatocytes, and the protein level of apoptosis-related protein Caspase 3 were reduced; the results of the dual-luciferase reporter gene assay showed that miR-383-5p targeted regulation of Bcl2. The results suggested that the expression of miR-383-5p was up-regulated in oxidative stress rat hepatocytes and may aggravate the apoptosis of rat hepatocytes induced by targeting inhibition of Bcl2 translation.


Asunto(s)
Apoptosis , MicroARNs , Estrés Oxidativo , Animales , Regulación hacia Abajo , Hepatocitos/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas
18.
Phys Rev Lett ; 122(10): 106101, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30932633

RESUMEN

In addition to their unique optical and electronic properties, two-dimensional materials provide opportunities to directly observe atomic-scale defect dynamics. Here we use scanning transmission electron microscopy to observe substitutional Re impurities in monolayer MoS_{2} undergo direct exchanges with neighboring Mo atoms in the lattice. Density-functional-theory calculations find that the energy barrier for direct exchange, a process that has only been studied as a diffusion mechanism in bulk materials, is too large for either thermal activation or energy directly transferred from the electron beam. The presence of multiple sulfur vacancies next to the exchanged Re-Mo pair, as observed by electron microscopy, does not lower the energy barrier sufficiently to account for the observed atomic exchange. Instead, the calculations find that a Re dopant and surrounding sulfur vacancies introduce an ever-changing set of deep levels in the energy gap. We propose that these levels mediate an "explosive" recombination-enhanced migration via multiple electron-hole recombination events. As a proof of concept, we also show that Re-Mo direct exchange can be triggered via controlled creation of sulfur vacancies. The present experimental and theoretical findings lay a fundamental framework towards manipulating single substitutional dopants in two-dimensional materials.

19.
Brain Behav Immun ; 76: 223-235, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30476565

RESUMEN

Stress induces many different sex-specific physiological and psychological responses during adolescence. Although the impact of certain brain stressors has been reported in the literature, the influence of cold stress on the mechanisms underlying hippocampal neurotransmitter disorder and neuroinflammation remain unstudied. Adolescent male and female C57BL/6 mice were exposed to 4 °C temperatures, 3 h per day for 1 week. Serum CORT and blood gas analysis was then used to assess body status. Using western blotting, immunofluorescence and immunohistochemistry we also assessed glial cell number and microglial activation, as well as inflammatory cytokine levels and related protein expression levels. The phenomena of excessive CORT, microglial activation, increased acetylate-HMGB1 levels, NF-κB signaling pathway activation, pro-inflammatory cytokine release, neuronal apoptosis and neurotransmitter disorder were demonstrated in mouse hippocampal tissue following cold exposure. We believe that these phenomena are mediated by the HMGB1/TLR4/NFκB pathway. Finally, the male inflammatory response in hippocampal tissue was more severe and the influence of cold exposure on neurotransmitter was greater in females.


Asunto(s)
Proteína HMGB1/metabolismo , Hipocampo/metabolismo , Neurotransmisores/metabolismo , Factores de Edad , Animales , Apoptosis/fisiología , Frío , Citocinas/metabolismo , Femenino , Inflamación/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Microglía/metabolismo , FN-kappa B/metabolismo , Neuroglía/metabolismo , Neuroinmunomodulación , Neuronas/metabolismo , Factores Sexuales , Transducción de Señal/fisiología , Estrés Fisiológico/fisiología , Lóbulo Temporal/metabolismo , Receptor Toll-Like 4/metabolismo
20.
BMC Gastroenterol ; 19(1): 219, 2019 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-31852444

RESUMEN

BACKGROUND: Alternate-day fasting (ADF) is a novel diet therapy that may achieve reduction in body weight and improvement of dyslipidaemia, but the impact of this diet on patients with non-alcoholic fatty liver disease (NAFLD) remains unknown. The aim of this study was to evaluate the effects of ADF on the body weight and lipid profile of individuals with NAFLD. METHODS: NAFLD patients (n = 271) were randomised to the ADF group, time-restricted feeding (TRF) group, or the control group and subjected to the respective diet for 12 weeks. Anthropometric measurements (body weight, fat mass/fat-free mass) were performed, and plasma lipids were analysed enzymatically. RESULTS: Within 4 weeks, the body weight decreased significantly (P < 0.001) in the ADF group by 4.56 ± 0.41 kg (6.1 ± 0.5%) and the TRF group by 3.62 ± 0.65 kg (4.83 ± 0.9%) compared to the control group, and it decreased even more after 12 weeks in both groups (ADF: - 4.04 ± 0.54 kg, 5.4 ± 0.7%; TRF: - 3.25 ± 0.67 kg, 4.3 ± 0.9%). Fat mass was significantly reduced by ADF (- 3.49 ± 0.37 kg; 11 ± 1.2%) and TRF (- 2.91 ± 0.41 kg; 9.6 ± 1.3%), with ADF leading to a further reduction in fat mass after 12 weeks (- 3.48 ± 0.38 kg; 11 ± 1.2%). Total cholesterol was significantly decreased at both time points in the ADF group (- 0.91 ± 0.07 mmol/L; 18.5 ± 1.5%) compared to the control and TRF groups. Both ADF (- 0.64 ± 0.06 mmol/L; 25 ± 1.9%) and TRF (0.58 ± 0.07 mmol/L; 20 ± 1.7%) achieved a significant reduction in serum triglycerides (P < 0.001) after 12 weeks. Changes in fat free mass, HDL, LDL, fasting insulin, glucose, liver stiffness, and systolic or diastolic blood pressure did not differ between the groups. CONCLUSIONS: ADF appears to be an effective diet therapy for individuals with NAFLD that can achieve weight loss and improvement of dyslipidaemia within a relatively short period of time (4 to 12 weeks). Potential preventive effects of ADF on cardiovascular disease need to be confirmed by future investigations. TRIAL REGISTRATION: ChiCTR1900024411, this trial was retrospectively registered on July 10, 2019.


Asunto(s)
Dislipidemias/dietoterapia , Ayuno , Conducta Alimentaria , Enfermedad del Hígado Graso no Alcohólico/dietoterapia , Pérdida de Peso , Adiposidad/fisiología , Adulto , Composición Corporal , Peso Corporal , Colesterol/sangre , Dislipidemias/sangre , Ingestión de Energía , Ayuno/sangre , Femenino , Humanos , Hambre , Masculino , Enfermedades Metabólicas/etiología , Enfermedad del Hígado Graso no Alcohólico/sangre , Evaluación de Resultado en la Atención de Salud , Factores de Riesgo , Factores de Tiempo , Triglicéridos/sangre
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