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1.
Exp Cell Res ; 435(2): 113923, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38190870

RESUMO

Atrial fibrillation (AF) is an extremely common clinical arrhythmia disease, but whether its mechanism is associated with ferroptosis remains unclear. The tRNA-derived small RNAs (tsRNAs) are involved in a variety of cardiovascular diseases, however, their role and mechanism in atrial remodeling in AF have not been studied. We aimed to explore whether tsRNAs mediate ferroptosis in AF progression. The AF models were constructed to detect ferroptosis-related indicators, and Ferrostatin-1 (Fer-1) was introduced to clarify the relationship between ferroptosis and AF. Atrial myocardial tissue was used for small RNA sequencing to screen potential tsRNAs. tsRNA functioned on ferroptosis and AF was explored. Atrial fibrosis and changes in the cellular structures and arrangement were observed in AF mice model, and these alterations were accompanied by ferroptosis occurrence, exhibited by the accumulation of Fe2+ and MDA levels and the decrease of expression of FTH1, GPX4, and SLC7A11. Blocking above ferroptosis activation with Fer-1 resulted in a significant improvement for AF. A total of 7 tsRNAs were upregulated (including tsRNA-5008a) and 2 tsRNAs were downregulated in atrial myocardial tissue in the AF group compared with the sham group. We constructed a tsRNA-mRNA regulated network, which showed tsRNA-5008a targeted 16 ferroptosis-related genes. Knockdown of tsRNA-5008a significantly suppressed ferroptosis through targeting SLC7A11 and diminished myocardial fibrosis both in vitro and in vivo. On the contrary, tsRNA-5008a mimics promoted ferroptosis in cardiomyocytes. Collectively, tsRNA-5008a involved in AF through ferroptosis. Our study provides novel insights into the role of tsRNA-5008a mediated ferroptosis in AF progression.


Assuntos
Fibrilação Atrial , Remodelamento Atrial , Cicloexilaminas , Ferroptose , Fenilenodiaminas , Animais , Camundongos , Fibrilação Atrial/genética , Miócitos Cardíacos , Remodelamento Atrial/genética , Ferroptose/genética , Átrios do Coração
2.
Biogerontology ; 24(5): 783-799, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36683095

RESUMO

Atherosclerosis threatens human health by developing cardiovascular diseases, the deadliest disease world widely. The major mechanism contributing to the formation of atherosclerosis is mainly due to vascular endothelial cell (VECs) senescence. We have shown that 17ß-estradiol (17ß-E2) may protect VECs from senescence by upregulating autophagy. However, little is known about how 17ß-E2 activates the autophagy pathway to alleviate cellular senescence. Therefore, the aim of this study is to determine the role of estrogen receptor (ER) α and ß in the effects of 17ß-E2 on vascular autophagy and aging through in vitro and in vivo models. Hydrogen peroxide (H2O2) was used to establish Human Umbilical Vein Endothelial Cells (HUVECs) senescence. Autophagy activity was measured through immunofluorescence and immunohistochemistry staining of light chain 3 (LC3) expression. Inhibition of ER activity was established using shRNA gene silencing and ER antagonist. Compared with ER-ß knockdown, we found that knockdown of ER-α resulted in a significant increase in the extent of HUVEC senescence and senescence-associated secretory phenotype (SASP) secretion. ER-α-specific shRNA was found to reduce 17ß-E2-induced autophagy, promote HUVEC senescence, disrupt the morphology of HUVECs, and increase the expression of Rb dephosphorylation and SASP. These in vitro findings were found consistent with the in vivo results. In conclusion, our data suggest that 17ß-E2 activates the activity of ER-α and then increases the formation of autophagosomes (LC3 high expression) and decreases the fusion of lysosomes with autophagic vesicles (P62 low expression), which in turn serves to decrease the secretion of SASP caused by H2O2 and consequently inhibit H2O2-induced senescence in HUVEC cells.


Assuntos
Receptor alfa de Estrogênio , Peróxido de Hidrogênio , Humanos , Receptor alfa de Estrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Células Cultivadas , Estradiol/farmacologia , Células Endoteliais da Veia Umbilical Humana , Autofagia
3.
J Environ Manage ; 338: 117824, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37004481

RESUMO

Effective management of pollutants in urban environments is crucial for achieving sustainable cities. Microplastics, as an emerging pollutant widely present in contemporary environments, have received widespread attention in recent years. However, limited studies have reported the impact of rapid urbanization on regional microplastics. In this study, the abundance and composition of microplastic communities in the sediments of Lake Aha were analyzed using a "microplastic community" and slicing the sediments at 5 cm intervals. Results showed that microplastic abundance of sediments in Lake Aha was relatively high (up to 1700 items/kg) and decreased with increasing depth, with the highest abundance found in the surface layer (0-5 cm, 1090 ± 474 items/kg). Hierarchical cluster analysis (HCA), principal component analysis (PCA), and analysis of similarities (ANOSIM) revealed that the different sediment layers could be classified into high and low urbanization level groups based on the composition of microplastic communities. Linear discriminant analysis effect size (LEfSe) indicated that agricultural input was the main source of microplastic pollution during low urbanization levels, characterized by low abundance, large particle size, and high fiber proportion, while urban activities dominated during high urbanization levels, with high abundance, small particle size, high proportion of Polyethylene terephthalate (PET), fragments, and granules, and colorful microplastics. This study clarifies the impact of urbanization on the abundance and composition of microplastics in lake sediments, which has implications for more effective management and control of microplastic pollution in regions undergoing rapid urbanization.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Microplásticos , Plásticos , Lagos , Urbanização , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Sedimentos Geológicos , China , Poluentes Ambientais/análise
4.
Biogerontology ; 21(5): 549-557, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32172411

RESUMO

17ß-estradiol (17ß-E2) has been implicated in inhibiting the senescence of vascular endothelial cells (VEC) and slowing down the process of atherosclerosis. However, the underlying molecular mechanisms are still unknown. In this study, we examined the roles of SIRT3 in 17ß-E2-induced autophagy and 17ß-E2-mediated inhibition of hydrogen peroxide (H2O2)-induced senescence in Human umbilical vein endothelial cells (HUVEC). Cellular senescence was measured by immunoblot analysis with antibodies against phosphorylated Rb and senescence-associated ß-galactosidase staining. Immunoblot analysis with antibodies against LC3 and p62 was performed to determine autophagy flux. Our findings show that 17ß-E2 activates SIRT3 promoter and upregulates SIRT3 gene expression in HUVEC cells. siRNA-mediated silencing of SIRT3 gene expression inhibits 17ß-E2-induced processing of LC3-I to LC3-II and degradation of p62, two widely-used makers of autophagy. SIRT3 knockdown also blocks 17ß-E2-induced inhibition of cellular senescence triggered by H2O2. Our data further reveal that SIRT3 knockdown impairs 17ß-E2-induced co-localization of LC3 and VDAC1, a marker protein on mitochondria, when HUVEC cells were co-treated with H2O2. Together, our findings suggest that 17ß-E2 upregulates SIRT3 gene expression by activating SIRT3 promoter and then promotes autophagy, which in turn serves to remove dysfunctional mitochondria caused by H2O2 and consequently inhibit H2O2-induced senescence in HUVEC cells.


Assuntos
Autofagia , Senescência Celular , Estradiol/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Sirtuína 3/metabolismo , Inativação Gênica , Humanos , Peróxido de Hidrogênio , Mitocôndrias/patologia
5.
Nano Lett ; 18(10): 6441-6448, 2018 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-30192559

RESUMO

Rechargeable Mg batteries, using high capacity and dendrite-free Mg metal anodes, are promising energy storage devices for large scale smart grid due to low cost and high safety. However, the performance of Mg batteries is still plagued by the slow reaction kinetics of their cathode materials. Recent discoveries demonstrate that water in cathode can significantly enhance the Mg-ion diffusion in cathode by an unknown mechanism. Here, we propose the water-activated layered-structure VOPO4 as a novel cathode material and examine the impact of water in electrode or organic electrolyte on the thermodynamics and kinetics of Mg-ion intercalation/deintercalation in cathodes. Electrochemical measurements verify that water in both VOPO4 lattice and organic electrolyte can largely activate VOPO4 cathode. Thermodynamic analysis demonstrates that the water in the electrolyte will equilibrate with the structural water in VOPO4 lattice, and the water activity in the electrolyte alerts the mechanism and kinetics for electrochemical Mg-ion intercalation in VOPO4. Theoretical calculations and experimental results demonstrate that water reduces both the solid-state diffusion barrier in the VOPO4 electrode and the desolvation penalty at the interface. To achieve fast reaction kinetics, the water activity in the electrolyte should be larger than 10-2. The proposed activation mechanism provides guidance for screening and designing novel chemistry for high performance multivalent-ion batteries.

7.
Phys Chem Chem Phys ; 18(6): 4460-7, 2016 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-26790481

RESUMO

Pseudocapacitors, which can store more energy at high charge/discharge rates, have attracted considerable attention. The performance of a pseudocapacitive material mainly depends on the interaction between electrode materials and the electrolyte ions. However, the understanding of the interaction is still limited. Here, the performance of Ti2CT2 (T = O, F, and OH) nanosheets as pseudocapacitor electrode materials has been investigated through a novel first-principles approach. The results suggest that O-terminated Ti2C nanosheets are shown to be pseudocapacitive cathode materials. The pseudocapacitance is attributed to the large intrinsic capacitance of Ti2CO2 nanosheets and contact adsorbed cations. The former mainly decides the capacity of charges and the latter reduces the change of potential in the electrode. The integral capacitance and Na-ion capacity of Ti2CO2 nanosheets are simulated to be 291.5 F g(-1) with a broad potential window range from 0 to 2.80 V (versus Na/Na(+)). Low diffusion energy barriers on Ti2CO2 and Ti2CF2 nanosheets indicate fast transportation and high charge and discharge rate for Na-ions. Our results provide insight into the origin of pseudocapacitance on stacked two-dimensional materials.

8.
Biogerontology ; 15(4): 367-75, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24938685

RESUMO

This study investigates the influence of 17beta-estradiol (E2) on hydrogen peroxide (H2O2)-induced human vascular endothelial cell (HUVEC) senescence. HUVECs were divided into four groups, namely control group, H2O2 stimulation group, E2 intervention group and ICI182780 (ICI) intervention group. The aging-related ß-galactosidase activities, cytochrome C oxidase activities, intracellular ATP levels, intracellular reactive oxygen species (ROS) levels and phosphorylated Rb protein expressions were mainly observed. Of which, senescence-associated ß-galactosidase activities were detected using immunohistochemical staining, cytochrome C oxidase activities and intracellular ATP levels were detected using commercial kits, ROS levels were detected by fluorescence microscopy and fluorescence microplate reader, immunoblotting was used to quantitatively detect the expressions of phosphorylated Rb proteins. After continuous treatment of H2O2, the senescent phenotypes appeared in the HUVECs. The percentage of positive SA-ßgal staining cells and the phosphorylated Rb expressions were significantly increased; intracellular ROS levels, cytochrome C oxidase activities and intracellular ATP levels were elevated. Compared with the H2O2 stimulation group, E2 intervention significantly decreased the positive rate of SA-ß-gal staining, the phosphorylated Rb protein levels, the intracellular ROS levels, cytochrome C oxidase activities and intracellular ATP levels. Pretreatment of estrogen receptor blocker ICI182780 weakened the role of E2. These results indicated that H2O2 could induce HUVEC senescence; 17beta-E2 might relieve H2O2-induced mitochondrial damage through estrogen receptor and delay the vascular endothelial cell senescence.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Estradiol/farmacologia , Peróxido de Hidrogênio/farmacologia , Mitocôndrias/efeitos dos fármacos , Endotélio Vascular/citologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Mitocôndrias/metabolismo
9.
Zhonghua Xin Xue Guan Bing Za Zhi ; 42(8): 641-5, 2014 Aug.
Artigo em Zh | MEDLINE | ID: mdl-25388335

RESUMO

OBJECTIVE: To investigate the impact of establishing regional collaborative network on reperfusion time and prognosis of patients with ST-segment elevated myocardial infarction (STEMI) admitting to community hospitals without percutaneous coronary intervention (PCI) capacity (Non-PCI hospital). METHODS: A regional collaborative network was developed, consisting of a PCI center and over 30 Non-PCI hospitals and connected by a tele-transmitted real-time 12-lead electrocardiogram system. This system enables the cardiologists on duty in PCI center to help the physicians in the Non-PCI hospitals (network hospital) to confirm the diagnosis and choose a reperfusion strategy for STEMI patients. All cardiologists in PCI center and physicians in Non-PCI hospitals were trained to follow the flowchart of reperfusion strategies for STEMI patients to shorten the reperfusion time. The mean time from door of Non-PCI hospital to needle of thrombolysis (D-to-N), the mean time from door of PCI center to balloon (D-to-B) and the mean time from the first medical contact to balloon (FMC-to-B) and the 1-year mortality were compared between the 20 months before and the 20 months after establishment of the regional collaborative network for patients with the first medical contact in three network hospitals. RESULTS: After establishment of the regional collaborative network, the mean D-to-N time was significantly shortened from (71 ± 62) min to (28 ± 9) min (P < 0.05), the rate of D-to-N below 30 min was increased from 11% (2/18) to 74% (26/35); the mean FMC-to-B and the mean D-to-B time were remarkably reduced in both complementary percutaneous coronary intervention and transfer percutaneous coronary intervention patients (all P < 0.05), the 1-year mortality post reperfusion was reduced from 15.1% (8/53) to 7.0% (10/142) (P < 0.05). CONCLUSION: The establishment of regional collaborative network could shorten the perfusion time and reduce the 1-year mortality for STEMI patients presenting to Non-PCI hospitals.


Assuntos
Infarto do Miocárdio/terapia , Intervenção Coronária Percutânea , Angioplastia Coronária com Balão , Eletrocardiografia , Hospitalização , Hospitais Comunitários , Humanos , Infarto do Miocárdio/mortalidade , Reperfusão Miocárdica , Transferência de Pacientes , Prognóstico , Fatores de Tempo
10.
RSC Adv ; 14(12): 7999-8006, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38454941

RESUMO

Aqueous alkaline zinc-based batteries (AAZBs) are promising for large-scale applications due to their high working voltage, safety, and low cost. However, the further development of AAZBs has been significantly hindered by the low electronic conductivity and poor cycling stability of traditional nickel/cobalt-based cathode materials. In this work, a binder-free electrode was successfully designed by electrodepositing NiCo-LDH nanosheets on NiCoS nanotube arrays that were grown on nickel foam (NiCoS@NiCo-LDH). The unique three-dimensional core-shell heterostructures not only enhance electrical conductivity but also offer abundant active sites and rapid ion/electron transport channels, thereby improving its electrochemical performance. The as-fabricated NiCoS@NiCo-LDH electrode delivers a capacity of 312 mA h g-1 (0.624 mA h cm-2) at 2 mA cm-2 and exhibits high rate capability with 90% capacity retention at 10 mA cm-2. Additionally, the assembled NiCoS@NiCo-LDH//Zn battery exhibits a high energy density of 435.3 W h kg-1 at a power density of 4.1 kW kg-1 and maintains 95.9% of its capacity after 3000 cycles at a current density of 20 mA cm-2.

11.
Int J Biol Macromol ; 258(Pt 1): 128794, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38110166

RESUMO

Sustainable and renewable biomass-derived porous carbon (BPC) have garnered considerable attention owing to their low cost, high specific surface area, and outstanding electrochemical performance. However, the subpar energy density severely restricts the applications of BPC in high-energy-density devices. Herein, a high-surface-area porous carbon with multiple heteroatoms doping was derived from rapeseed meals by hydrothermal carbonization and high-temperature activation. The rapeseed meal-derived activated carbon (RMAC) exhibits a remarkable surface area of 3291 m2 g-1 and is doped with nitrogen (1.05 at.%), oxygen (7.4 at.%), phosphorus (0.31 at.%), and sulfur, resulting in an impressive specific capacitance of 416 F g-1 at 1 A g-1. Furthermore, even after 10,000 cycles, the optimized RMAC-800 electrode maintains 92 % of its initial capacitance, attesting to its exceptional performance. Through comprehensive density functional theory (DFT) calculations, the elements O, N, P, and S can significantly enhance the electron negativity and density, improving the adsorption and diffusion of K+ to attain a high capacitance. To assess the RMAC-800's practical performance, an asymmetric supercapacitor with 1 M [BMIM]BF4/AN electrolyte was produced that delivered a high energy density of 195.94 Wh kg-1 at a power density of 1125 W kg-1. Thus, we propose an eco-friendly strategy for producing BPC materials with outstanding electrochemical performance for supercapacitors.


Assuntos
Brassica napus , Brassica rapa , Adsorção , Potássio , Biomassa , Porosidade , Fenômenos Físicos , Carvão Vegetal
12.
Zhonghua Xin Xue Guan Bing Za Zhi ; 41(7): 568-71, 2013 Jul.
Artigo em Zh | MEDLINE | ID: mdl-24284183

RESUMO

OBJECTIVE: To investigate the impact of the establishment of chest pain center (CPC) model based on the pre-hospital real-time tele-12-lead electrocardiogram on the door-to-balloon (D-to-B) time and short-term outcome after primary percutaneous coronary intervention (PPCI) of patients with ST-segment elevated myocardial infarction (STEMI). METHODS: A regular CPC was established with pre-hospital transmitted real-time 12-lead electrocardiogram system for pre-hospital diagnosis of STEMI and enabled the STEMI patients to bypass the emergency room and directly treated in the catheter lab to shorten the D-to-B time. The mean D-to-B time, the short-term outcome and medical costs were compared in PPCI patients before (93 cases, group A) and after (149 cases, group B) the establishment of CPC. RESULTS: After the establishment of CPC, the annual mean D-to-B time was significantly shortened [(127 ± 79) min in group A vs.(72 ± 23 )min in group B, P < 0.01], the shortest monthly mean D-to-B time was remarkably reduced in group B than in group A [(56 ± 11) min vs. (73 ± 14) min, P < 0.01]. The annual ratio of D-to-B below 90 minutes was significantly increased from 62.4% (58/93) in group A to 91.9% (137/149) in group B (P < 0.05) . The in-hospital mortality rate tended to be lower and the incidence of heart failure during hospitalization was significantly reduced in group B compared with group A [3.4% (5/149) vs. 6.5% (6/93), P > 0.05; 14.1% (21/149) vs. 24.7% (23/93), P < 0.05]. The length of hospital stay was slightly shortened from (8.98 ± 4.89) days to (7.79 ± 5.43) days (P > 0.05). Corrected mean medical cost went down by 9.4% (P < 0.05). CONCLUSION: The establishment of CPC may significantly shorten the D-to-B time, improve the short-term outcome and reduce the hospitalization cost for PPCI patients with STEMI.


Assuntos
Infarto do Miocárdio/terapia , Intervenção Coronária Percutânea , Adulto , Idoso , Angioplastia Coronária com Balão , Dor no Peito/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Tempo
13.
Sci Total Environ ; 905: 166638, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37657545

RESUMO

The rivers have been proven to be potential sources and the major transport pathways of microplastic (MP) in natural aquatic eco-systems, yet there is an absence of understanding the provenances and distribution dynamics of MP in fluvial water body of urban regions. The present investigation aimed to characterize the distribution and accumulation of MPs in both surface water and riverine bed sediments in a typical urban river (Nanming River, southwest China), during the dry and wet seasons of 2021. MP were detected throughout the entire sample set, with average surface water abundances of 750 ± 53 n/m3 and 693.3 ± 40 n/m3 in dry and wet seasons, respectively, and 2250 ± 496.7 n/kg (dw) in surface sediments. Furthermore, the composition of 25 polymer types MPs were analyzed. The sediment of the Nanming River is a sink for MPs, recording their long-term accumulation. Multivariate statistical analysis-based results indicated that urban littering and agricultural input were the major contributors of non-point MP in the Nanming River, while the discharged effluent was another factor influencing the distribution of MPs in urban fluvial system. The average abundance of MPs was negatively correlated with purchase power parity (PPP), demonstrating that the poorly waste management results in a higher abundance of MPs in municipal river systems. The present study systematically characterized the distribution of MPs in medium-sized urban rivers systems in Southwest China. These findings can inform policy and management decisions to reduce MPs pollution in urban rivers and protect aquatic ecosystems.

14.
Environ Pollut ; 320: 121076, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36641065

RESUMO

Microplastic pollution threatens water systems worldwide. As one of the most important parts of city wastewater treatment, wastewater treatment plants are not only microplastics interception barriers but also emission sources. Water samples were collected from each sewage treatment plant stage and sludge from the sludge dewatering room. Microplastics were extracted using wet peroxide oxidation and flotation, and the abundance, size, shape, and polymer type of microplastics were detected. Basis on the results, the influence of each process on the removal rate and characteristics of microplastics under the same influent source was analysed. The influent microplastic concentration in this study was 32.5 ± 1.0 n/L, which rapidly decreased after treatment. The removal rates of the sequencing batch reactor activated sludge, cyclic activated sludge, and anaerobic anoxic oxic technologies were 73.0%, 75.6%, and 83.9%, respectively. Most microplastics were transported to the sludge, and the concentration of microplastics in dehydrated sludge was 27.2 ± 3.1 n/g. Microplastics removal occurred primarily during the primary and secondary stages. Disposal processes, settling time, and process design affected wastewater treatment plant microplastic removal rates at each stage. Significant differences in microplastic characteristics were observed at each stage, with the most abundant being fragment shaped, particle sizes of 30-100 µm, and black in colour. Sixteen polymer types were identified using a Raman spectrometer. The predominant polymers are polypropylene, polyethylene, and polyethylene terephthalate. This study demonstrates that optimising the process design of existing wastewater treatment plants is crucial for the prevention and control of microplastic pollution. It is suggested that the process settings of contemporary wastewater treatment plants should be studied in depth to develop a scientific foundation for avoiding and managing microplastic pollution in urban areas.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Microplásticos , Plásticos , Esgotos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Água/análise , Eliminação de Resíduos Líquidos/métodos
15.
ChemSusChem ; 16(8): e202202257, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-36624068

RESUMO

Aqueous sodium-ion batteries (ASIB) offer many potential applications in large-scale power grids since they are inexpensive, safe, and environmentally friendly. Sodium superionic conductors (NASICON), especially carbon-coated Na3 V2 (PO4 )3 (NVP), have attracted much attention due to the full use of their high ion migration speed. However, the poor cycle lifespan and capacity retention of NVP hinder its application in ASIB. Herein, a novel bimetal-doped Na3 V1.3 Fe0.5 W0.2 (PO4 )3 (NV1.3 Fe0.5 W0.2 P) cathode is designed and synthesized to achieve outstanding cycling stability (95 % of initial capacity at 50th cycle). The electrochemical behavior and charge storage mechanism of NV1.3 Fe0.5 W0.2 P are systematically investigated by various in situ and ex situ characterizations. The Fe and W codoping could stabilize the NASICON framework to suppress the proton attack on the Na site in the aqueous electrolyte, thus resulting in excellent cycling stability. DFT calculations show that bimetallic doping increases the structural stability of NVP. Moreover, an ASIB fabricated using a NV1.3 Fe0.5 W0.2 P cathode and a NaTi2 (PO4 )3 anode delivers 64 mAh g-1 at room temperature, 95 % capacity retention after 50 cycles (1 A g-1 ).

16.
J Steroid Biochem Mol Biol ; 227: 106244, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36584773

RESUMO

OBJECTIVE: 17ß-estradiol (17ß-E2) has been implicated in activating autophagy by upregulating SIRT3 (Sirtuin 3) expression, thereby inhibiting the senescence of vascular endothelial cells. Herein, we further examined the molecular mechanisms that regulate SIRT3 expression in 17ß-E2-induced autophagy. METHODS: Reverse-transcription-polymerase chain reaction was employed to measure the expression of plasmacytoma variant translocation 1 (PVT1), microRNAs (miRNAs), and SIRT3, and the dual-luciferase assay was used to determine their interaction. Electron microscopy observes autophagosomes, green fluorescent protein-microtubule-associated protein 1 light chain 3 (GFP-LC3) staining, and immunoblot analysis with antibodies against LC3,beclin-1, and P62 were conducted to measure autophagy. Cellular senescence was determined using immunoblot analysis with anti-phosphorylated retinoblastoma and senescence-associated ß-galactosidase staining. RESULTS: Women with higher estrogen levels (during the 10-13th day of the menstrual cycle or premenopausal) exhibit markedly higher serum levels of PVT1 than women with lower estrogen levels (during the menstrual period or postmenopausal). The dual-luciferase assay showed that PVT1 acts as a sponge for miR-31, and miR-31 binds to its target gene, SIRT3. The 17ß-E2 treatment increased the expression of PVT1 and SIRT3 and downregulated miR-31 expression in human umbilical vein endothelial cells (HUVECs). Consistently, PVT1 overexpression suppresses miR-31 expression, promotes 17ß-E2-induced autophagy, and inhibits H2O2-induced senescence. miR-31 inhibitor increases SIRT3 expression and leads to activation of 17ß-E2-induced autophagy and suppression of H2O2-induced senescence. CONCLUSION: Our findings demonstrated that 17ß-E2 upregulates PVT1 gene expression and PVT1 functions as a sponge to inhibit miR-31, resulting in the upregulation of SIRT3 expression and activation of autophagy and subsequent inhibition of H2O2-induced senescence in HUVECs.


Assuntos
MicroRNAs , RNA Longo não Codificante , Sirtuína 3 , Humanos , Feminino , Sirtuína 3/genética , Células Endoteliais da Veia Umbilical Humana , Peróxido de Hidrogênio/farmacologia , MicroRNAs/genética , Estradiol/farmacologia , Estrogênios , Autofagia , RNA Longo não Codificante/genética
17.
J Colloid Interface Sci ; 621: 139-148, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35452927

RESUMO

To meet the crucial demand for high-performance supercapacitors, much effort has been devoted to exploring electrode materials with nanostructures and electroactive chemical compositions. Herein, iron carbide nanoparticles are encapsulated into carbon nanofibers (Fe3C@CNF-650) through electrospinning and annealing methods. Nickel-cobalt sulfide nanoparticles are hydrothermally grown on electrospun carbon nanofibers (CNF@NiCoS-650). The Faradaic electrochemical reactions of transition metal compounds improve the specific capacitance of the developed electrode. Meanwhile, the electrically conductive framework of carbon nanofibers facilitates Faradic charge transport. In detail, the Fe3C@CNF-650 anode and CNF@NiCoS-650 cathode achieve specific capacitances of 1551 and 205 F g-1, respectively, at a current density of 1 A g-1. A hybrid supercapacitor that is fabricated from the Fe3C@CNF-650 anode and CNF@NiCoS-650 cathode delivers an energy density of 43.2 Wh kg-1 at a power density of 800 W kg-1. The designed nanostructures are promising for practical supercapacitor applications.

18.
J Colloid Interface Sci ; 610: 1088-1099, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34876262

RESUMO

Fabrication of porous activated carbon derived from biomass waste with high surface area, specific porosity, and excellent electroactivity has attracted much more attention in the energy conversion and storage field. Herein, mango seed waste is utilized as a precursor to synthesize nitrogen (N) and oxygen (O) co-doped porous carbon by high-temperature carbonization coupling with subsequent KOH activation. The more KOH activator was fed in the high-temperature activation process, the larger surface area, higher micropore ratio, and lower N and O doping content of the activated carbon was obtained. The optimized mango seed-derived activated carbon (MSAC) exhibits high surface area (1815 m2 g-1), micropore ratio (94%), doping content of nitrogen (1.71 at.%), and oxygen (10.93 at.%), which delivers an ultrahigh specific capacitance of 402F g-1 at 1 A g-1 and retains 102.4% of initial capacitance after 5000 cycles. The supercapacitor performance of MSAC was also investigated in 6 M KOH, 1 M [BMIM]BF4/AN, and PVA/KOH electrolytes in detail, respectively. A flexible all-solid-state asymmetric supercapacitor (FSAS) fabricated by MSAC anode, CoNiAl layered double hydroxides cathode, and PVA/KOH electrolyte achieves a high energy density of 33.65 Wh kg-1 at a power density of 187.5 W kg-1 and retains 80% of initial capacitance after 10,000 cycles. The low cost, facile synthetic process, and excellent electrochemical performance of MSAC electrode material provide a cheap and accessible strategy to obtain porous carbon material for energy conversion and storage systems.


Assuntos
Nitrogênio , Oxigênio , Biomassa , Capacitância Elétrica , Eletrodos
19.
Dis Markers ; 2022: 8307975, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35154514

RESUMO

BACKGROUND: Atrial fibrillation (AF) is the most common arrhythmia in the world. Long noncoding RNA (lncRNA) has been found to play an important role in cardiovascular diseases including heart failure, myocardial infarction, and atherosclerosis. However, the role of lncRNA in AF has rarely been studied. The purpose of this study is to identify the expression profile of lncRNA in AF patients, explore the function of lncRNA in AF, and provide a potential scientific basis for the treatment of AF in the future. METHODS: The lncRNA and mRNA expression profiles were obtained from the atrial appendage samples of GSE31821, GSE411774, GSE79768, and GSE115574 in the Gene Expression Omnibus (GEO) database. Functional analysis was performed via Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Variation Analysis (GSVA). The "CIBERSORT" R kit was used to analyze 22 immune cell infiltrates in AF and sinus rhythm (SR) patients. The "CORRPLOT" R package was used to analyze the immune correlation between lncRNA and immune cells. RESULTS: A total of 6 differentially expressed lncRNAs and 45 differentially expressed mRNAs were identified in the AF and SR groups. GO, KEGG, and GSVA results showed that abnormally expressed lncRNAs were involved in signaling pathways related to the atrium, including the Toll-like receptor signaling pathway and calcium signaling pathway. Immune cell infiltration analysis revealed that native B cells, follicular helper T cells, and resting dendritic cells may be involved in the AF process. In addition, LINC00844 was negatively correlated with resting dendritic cells. CONCLUSION: The expression profile of lncRNA in AF patients was different from that in normal controls. The physiological functions of these differentially expressed lncRNAs may be related to the pathogenesis of AF, which provide a scientific basis for the prognosis and treatment of patients with AF.


Assuntos
Fibrilação Atrial/genética , Biologia Computacional , RNA Longo não Codificante/genética , Humanos
20.
J Colloid Interface Sci ; 627: 913-921, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35901570

RESUMO

Na3V2(PO4)3 (NVP), which is known as a sodium superionic conductor (NASICON), has been successfully developed as an excellent cathode material for sodium-ion batteries (SIBs). However, the capacity of NVP quickly fades when used in an aqueous electrolyte. Herein, the charge storage and capacity attenuation mechanisms of carbon-coated NVP (NVP@C) were carefully investigated by systematic material characterization and density functional theory (DFT) calculations. According to the results, protons in the aqueous electrolyte diffuse into the surface of NVP@C to occupy the sodium site and attack the nearby phosphates during the charge-discharge cycles, leading to the deformation and breakage of the POV bond. The distorted phosphates on the surface of NVP@C gradually dissolve into the electrolyte, causing a decrease in capacity. To stabilize the phosphates on the surface of NVP, DFT calculations suggest that iron doping of NVP can effectively relieve the deformation of the POV bond and suppress the capacity decay. The as-prepared Na3V1.5Fe0.5(PO4)3@C (NV1.5Fe0.5P@C) has a capacity retention of 95% in the first ten cycles, while NVP@C retains only 55% of the initial capacity in the same number of cycles.

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