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1.
Nature ; 621(7977): 75-81, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37673990

RESUMEN

Benefiting from high energy density (2,600 Wh kg-1) and low cost, lithium-sulfur (Li-S) batteries are considered promising candidates for advanced energy-storage systems1-4. Despite tremendous efforts in suppressing the long-standing shuttle effect of lithium polysulfides5-7, understanding of the interfacial reactions of lithium polysulfides at the nanoscale remains elusive. This is mainly because of the limitations of in situ characterization tools in tracing the liquid-solid conversion of unstable lithium polysulfides at high temporal-spatial resolution8-10. There is an urgent need to understand the coupled phenomena inside Li-S batteries, specifically, the dynamic distribution, aggregation, deposition and dissolution of lithium polysulfides. Here, by using in situ liquid-cell electrochemical transmission electron microscopy, we directly visualized the transformation of lithium polysulfides over electrode surfaces at the atomic scale. Notably, an unexpected gathering-induced collective charge transfer of lithium polysulfides was captured on the nanocluster active-centre-immobilized surface. It further induced an instantaneous deposition of nonequilibrium Li2S nanocrystals from the dense liquid phase of lithium polysulfides. Without mediation of active centres, the reactions followed a classical single-molecule pathway, lithium polysulfides transforming into Li2S2 and Li2S step by step. Molecular dynamics simulations indicated that the long-range electrostatic interaction between active centres and lithium polysulfides promoted the formation of a dense phase consisting of Li+ and Sn2- (2 < n ≤ 6), and the collective charge transfer in the dense phase was further verified by ab initio molecular dynamics simulations. The collective interfacial reaction pathway unveils a new transformation mechanism and deepens the fundamental understanding of Li-S batteries.

2.
J Am Chem Soc ; 146(7): 4557-4569, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38345667

RESUMEN

Intelligent utilization of the anionic redox reaction (ARR) in Li-rich cathodes is an advanced strategy for the practical implementation of next-generation high-energy-density rechargeable batteries. However, due to the intrinsic complexity of ARR (e.g., nucleophilic attacks), the instability of the cathode-electrolyte interphase (CEI) on a Li-rich cathode presents more challenges than typical high-voltage cathodes. Here, we manipulate CEI interfacial engineering by introducing an all-fluorinated electrolyte and exploiting its interaction with the nucleophilic attack to construct a gradient CEI containing a pair of fluorinated layers on a Li-rich cathode, delivering enhanced interfacial stability. Negative/detrimental nucleophilic electrolyte decomposition has been efficiently evolved to further reinforce CEI fabrication, resulting in the construction of LiF-based indurated outer shield and fluorinated polymer-based flexible inner sheaths. Gradient interphase engineering dramatically improved the capacity retention of the Li-rich cathode from 43 to 71% after 800 cycles and achieved superior cycling stability in anode-free and pouch-type full cells (98.8% capacity retention, 220 cycles), respectively.

3.
Anal Biochem ; 685: 115409, 2024 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-38006953

RESUMEN

Aptamers are widely used in various biomedical areas as novel molecular recognition elements, however, short single-stranded DNA (ssDNA) or RNA oligonucleotides are easily degraded by nucleases in biological fluids. This problem can be solved by circularizing aptamers with circular ligases. Herein, a moderately thermostable ssDNA ligase was expressed and purified. The purified ligase showed good circularization activity for different length substrates and much higher circularization efficiency than T4 RNA ligase 1. Biochemical characterization revealed that the enzyme showed optimal circularization activity at pH 7.5 and 50 ᵒC. Mn2+ and Mg2+ increased enzyme circularization activity, with Mn2+ having higher activity than Mg2+. The optimal concentrations of Mn2+ and ligase were 1.25-2.5 mM and 0.02 nM, respectively. The kinetic parameters Km, Vmax and Kcat of ssDNA ligase were 1.16 µM, 10.71 µM/min, and 10.7 min-1, respectively. The ssDNA ligase efficiency was nucleotide-dependent, and 5'-G and 3'-T were the most ligase-favored terminal nucleotides. In addition, the affinity and stability of the circular aptamer were determined. The affinity constant (KD) was 4.9 µM, and the stability increased compared to its linear form. Molecular docking results showed that the circular aptamer bound to the target via two hydrogen bonds. This study provides a simple and efficient aptamer circularization modification method for improving aptamer stability and expanding its applications.


Asunto(s)
Aptámeros de Nucleótidos , ADN de Cadena Simple , Ligasas/metabolismo , Simulación del Acoplamiento Molecular , ARN/química , Aptámeros de Nucleótidos/química
4.
Ann Hematol ; 103(7): 2463-2473, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38758360

RESUMEN

The combination of cladribine, cytarabine, and G-CSF (CLAG) has exhibited robust synergistic anti-leukemia activity as an induction therapy (IT) in acute myeloid leukemia (AML). However, the impact of CLAG as a bridging therapy (BT) administered between IT and allogeneic hematopoietic stem cell transplantation (allo-HSCT) for patients with relapsed or refractory (R/R) AML remains uncertain. In this retrospective study, we examined the efficacy of CLAG as a transitional strategy prior to allo-HSCT in R/R AML. We included 234 patients with R/R AML who received the modified busulfan plus cyclophosphamide conditioning regimen for allo-HSCT in our center during the past 6 years, performed a propensity-score matching analysis, partitioned them into four distinct cohorts, and further integrated them into the CLAG group and non-CLAG group based on response to IT and utilization of CLAG. Our cohorts encompassed 12 patients in Cohort A (modified composite complete remission (mCRc) after IT, CLAG), 31 in Cohort B (mCRc after IT, non-CLAG), 35 in Cohort C (non-complete remission (non-CR) after IT, CLAG), and 80 in Cohort D (non-CR after IT, non-CLAG). Intriguingly, among patients with non-CR status, the administration of CLAG correlated with a notably statistically diminished risk of relapse and improved survival at 2-year follow-up (Cohort C vs. Cohort D). Employing CLAG as a BT prior to allo-HSCT demonstrates substantial effectiveness, a relative degree of safety, and manageable toxicity in selected R/R AML cases.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Cladribina , Citarabina , Factor Estimulante de Colonias de Granulocitos , Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Humanos , Citarabina/administración & dosificación , Citarabina/uso terapéutico , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/tratamiento farmacológico , Masculino , Femenino , Persona de Mediana Edad , Adulto , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Cladribina/uso terapéutico , Cladribina/administración & dosificación , Estudios Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Anciano , Adulto Joven , Trasplante Homólogo , Recurrencia , Adolescente , Acondicionamiento Pretrasplante/métodos , Aloinjertos
5.
Sensors (Basel) ; 24(6)2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38544053

RESUMEN

The carbon-fiber-reinforced polymer (CFRP) bending structure is widely used in aviation. The emergence and spread of delamination damage will decrease the safety of in-service bending structures. Lamb waves can effectively identify delamination damage as a high-damage-sensitivity detection tool. For this present study, the signal difference coefficient (SDC) was introduced to quantify delamination damage and evaluate the sensitivity of A0-mode and S0-mode Lamb waves to delamination damage. The simulation results show that compared with the S0-mode Lamb wave, the A0-mode Lamb wave exhibits higher delamination damage sensitivity. The delamination damage can be quantified based on the strong correlation between the SDC and the delamination damage size. The control effect of the linear array PZT phase time-delay method on the Lamb wave mode was investigated by simulation. The phase time-delay method realizes the generation of a single-mode Lamb wave, which can separately excite the A0-mode and S0-mode Lamb wave to identify delamination damage of different sizes. The A0-mode Lamb wave was excited by the developed one-dimensional miniaturized linear comb transducer (LCT), which was used to conduct the detection experiment on the CFRP bending plate with delamination damage sizes of Φ6.0 mm, Φ10.0 mm, and Φ15.0 mm. The experimental results verify the correctness of the simulation. According to the Hermite interpolation results of the finite-element simulation data, the relationship between the delamination damage size and the SDC was fitted by the Gaussian function and Rational function, which can accurately quantify the delamination damage. The absolute error of the delamination damage quantification with Gaussian and Rational fitting expression does not exceed 0.8 mm and 0.7 mm, and the percentage error is not more than 8% and 7%. The detection and signal processing methods employed in the present research are easy to operate and implement, and accurate delamination damage quantification results have been obtained.

6.
Angew Chem Int Ed Engl ; 63(6): e202316790, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38116869

RESUMEN

Electrolyte engineering is a fascinating choice to improve the performance of Li-rich layered oxide cathodes (LRLO) for high-energy lithium-ion batteries. However, many existing electrolyte designs and adjustment principles tend to overlook the unique challenges posed by LRLO, particularly the nucleophilic attack. Here, we introduce an electrolyte modification by locally replacing carbonate solvents in traditional electrolytes with a fluoro-ether. By benefit of the decomposition of fluoro-ether under nucleophilic O-related attacks, which delivers an excellent passivation layer with LiF and polymers, possessing rigidity and flexibility on the LRLO surface. More importantly, the fluoro-ether acts as "sutures", ensuring the integrity and stability of both interfacial and bulk structures, which contributed to suppressing severe polarization and enhancing the cycling capacity retention from 39 % to 78 % after 300 cycles for the 4.8 V-class LRLO. This key electrolyte strategy with comprehensive analysis, provides new insights into addressing nucleophilic challenge for high-energy anionic redox related cathode systems.

7.
J Am Chem Soc ; 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-37029335

RESUMEN

Element doping/substitution has been recognized as an effective strategy to enhance the structural stability of layered cathodes. However, abundant substitution studies not only lack a clear identification of the substitution sites in the material lattice, but the rigid interpretation of the transition metal (TM)-O covalent theory is also not sufficiently convincing, resulting in the doping/substitution proposals being dragged into design blindness. In this work, taking Li1.2Ni0.2Mn0.6O2 as a prototype, the intense correlation between the "disordered degree" (Li/Ni mixing) and interface-structure stability (e.g., TM-O environment, slab/lattice, and Li+ reversibility) is revealed. Specifically, the degree of disorder induced by the Mg/Ti substitution extends in the opposite direction, conducive to sharp differences in the stability of TM-O, Li+ diffusion, and anion redox reversibility, delivering fairly distinct electrochemical performance. Based on the established paradigm of systematic characterization/analysis, the "degree of disorder" has been shown to be a powerful indicator of material modification by element substitution/doping.

8.
Nano Lett ; 22(2): 815-821, 2022 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-34994574

RESUMEN

The Li-O2 battery should operate effectively/safely in an open O2 environment for practical applications, but not trapped in sealed/closed atmosphere. However, the typical use of volatile and flammable electrolyte restricts Li-O2 battery to be able to be running in open O2 environment. We report herein, for the first time, a highly electrochemical reversible Li-O2 battery operated in an open O2 environment, i.e., under the condition of keeping O2 flowing continuously based on a nonvolatile and nonflammable sulfolane (TMS) solvent. The electrochemical irreversibility of Li2O2/O2 conversion and incompatibility between Li metal anodes and electrolyte have been addressed via dissolving LiNO3 in concentrated TMS electrolyte. The tuned electrolyte not only enables a stable solid electrolyte interphase (SEI) with conformal inorganic components (including LiF, LiNxOy, and Li2O) that promotes a uniform Li electro-plating/stripping process but also results in a low charge overpotential, a stable discharge terminal plateau, and reversible O2 generation of the Li-O2 battery conducted in an open O2 environment.

9.
Nano Lett ; 22(6): 2538-2546, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35266715

RESUMEN

Aqueous zinc iodide (Zn-I2) batteries are promising large-scale energy-storage devices. However, the uncontrollable diffuse away/shuttle of soluble I3- leads to energy loss (low Coulombic efficiency, CE), and poor reversibility (self-discharge). Herein, we employ an ordered framework window within a zeolite molecular sieve to restrain I3- crossover and prepare zeolite molecular sieve particles into compact, large-scale, and flexible membranes at the engineering level. The as-prepared membrane can confine I3- within the catholyte region and restrain its irreversible escape, which is proved via space-resolution and electrochemical in situ time-resolution Raman technologies. As a result, overcharge/self-discharge and Zn corrosion are effectively controlled by zeolite separator. After replacing the typically used glass fiber separator to a zeolite membrane, the CE of Zn-I2 battery improves from 78.9 to 98.6% at 0.2 A/g. Besides, after aging at the fully charged state for 5.0 h, self-discharge is restrained and CE is enhanced from 44.0 to 85.65%. Moreover, the Zn-I2 cell maintains 91.0% capacity over 30,000 cycles at 4.0 A/g.

10.
Nano Lett ; 22(12): 4985-4992, 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35686884

RESUMEN

As a full cell system with attractive theoretical energy density, challenges faced by Li-O2 batteries (LOBs) are not only the deficient actual capacity and superoxide-derived parasitic reactions on the cathode side but also the stability of Li-metal anode. To solve simultaneously intrinsic issues, multifunctional fluorinated graphene (CFx, x = 1, F-Gr) was introduced into the ether-based electrolyte of LOBs. F-Gr can accelerate O2- transformation and O2--participated oxygen reduction reaction (ORR) process, resulting in enhanced discharge capacity and restrained O2--derived side reactions of LOBs, respectively. Moreover, F-Gr induced the F-rich and O-depleted solid electrolyte interphase (SEI) film formation, which have improved Li-metal stability. Therefore, energy storage capacity, efficiency, and cyclability of LOBs have been markedly enhanced. More importantly, the method developed in this work to disperse F-Gr into an ether-based electrolyte for improving LOBs' performances is convenient and significant from both scientific and engineering aspects.

11.
Nano Lett ; 22(17): 6958-6963, 2022 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-36037446

RESUMEN

The kinetics of mass transfer in a stagnant fluid layer next to an interface govern numerous dynamic reactions in diffusional micro/nanopores, such as catalysis, fuel cells, and chemical separation. However, the effect of the interplay between stagnant liquid and flowing fluid on the micro/nanoscopic mass transfer dynamics remains poorly understood. Here, by using liquid cell transmission electron microscopy (TEM), we directly tracked microfluid unit migration at the nanoscale. By tracking the trajectories, an unexpected mass transfer phenomenon in which fluid units in the stagnant liquid layer migrated two orders faster during gas-liquid interface updating was identified. Molecular dynamics (MD) simulations indicated that the chemical potential difference between nanoscale liquid layers led to convective flow, which greatly enhanced mass transfer on the surface. Our study opens up a pathway toward research on mass transfer in the surface liquid layers at high spatial and temporal resolutions.


Asunto(s)
Nanoporos , Difusión , Cinética , Microfluídica , Microscopía Electrónica de Transmisión
12.
Angew Chem Int Ed Engl ; 62(36): e202303789, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37198522

RESUMEN

Stabilizing liquids based on supramolecular assembly (non-covalent intermolecular interactions) has attracted significant interest, due to the increasing demand for soft, liquid-based devices where the shape of the liquid is far from the equilibrium spherical shape. The components comprising these interfacial assemblies must have sufficient binding energies to the interface to prevent their ejection from the interface when the assemblies are compressed. Here, we highlight recent advances in structuring liquids based on non-covalent intermolecular interactions. We describe some of the progress made that reveals structure-property relationships. In addition to treating advances, we discuss some of the limitations and provide a perspective on future directions to inspire further studies on structured liquids based on supramolecular assembly.

13.
Angew Chem Int Ed Engl ; 62(27): e202303343, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37138389

RESUMEN

In sodium-ion batteries (SIBs), the low initial coulombic efficiency (ICE) is commonly induced by irreversible phase conversion and difficult desodiation, especially on transition metal compounds (TMCs). Yet the underlying physicochemical mechanism of poor reaction reversibility is still a controversial issue. Herein, by using in situ transmission electron microscopy and in situ X-ray diffraction, we demonstrate the irreversible conversion of NiCoP@C is caused by the rapid migration of P in carbon layer and preferential formation of isolated Na3 P during discharge. By modifying the carbon coating layer, the migration of Ni/Co/P atoms is inhibited, thus the improvement of ICE and cycle stability is realized. The inhibiting of fast atom migration which induces component separation and rapid performance degradation might be applied to a wide range of electrode materials, and guides the development of advanced SIBs.

14.
J Chem Phys ; 157(23): 230901, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36550040

RESUMEN

Li metal batteries (LMBs) reveal great application prospect in next-generation energy storage, because of their high energy density and low electrochemical potential, especially when paired with elemental sulfur and oxygen cathodes. Complex interfacial reactions have long been a big concern because of the elusive formation/dissolution of Li metal at the solid-electrolyte interface (SEI) layer, which leads to battery degradation under practical operating conditions. To precisely track the reactions at the electrode/electrolyte interfaces, in the past ten years, high spatio-temporal resolution, in situ electrochemical transmission electron microscopy (EC-TEM) has been developed. A preliminary understanding of the structural and chemical variation of Li metal during nucleation/growth and SEI layer formation has been obtained. In this perspective, we give a brief introduction of liquid cell development. Then, we comparably discuss the different configurations of EC-TEM based on open-cell and liquid-cell, and focus on the recent advances of liquid-cell EC-TEM and its investigation in the electrodes, electrolytes, and SEI. Finally, we present a perspective of liquid-cell EC-TEM for future LMB research.

15.
Environ Monit Assess ; 195(1): 192, 2022 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-36512138

RESUMEN

Wetlands are fragile ecosystems that are sensitive to human activities. In mining cities with high groundwater tables, underground mining, urbanization, and land reclamation cause severe disturbance to wetland landscape patterns, which poses a serious threat to the integrity and sustainability of the regional wetland ecosystems. This paper extracted the dynamic patterns of wetlands in Huaibei, China, from the Landsat TM/ETM remote sensing images with a time duration of 30 years from 1991 to 2021. The land-use transfer matrix and the landscape metrics were used to analyze the dynamic evolution of the wetland landscape patterns in this typical mining city. Afterwards, the human disturbance changes in the wetlands during the past 30 years were analyzed by the human disturbance transformation index (HTI). The correlation between the HTI and the changes in the landscape metrics were analyzed to reflect the influences of different human disturbance mechanisms on the evolution of the wetland landscape patterns. The results indicated that the wetland areas gradually increased with rising human disturbance levels from 1991 to 2021. However, the wetland landscape patterns showed a trend of declining landscape connectivity and fragmentation. The human disturbance levels to the wetlands were found significantly increased from 1991 to 2005 and from 2010 to 2015, and declined from 2005 to 2010 and from 2015 to 2021. The correlation between the HTI and landscape metrics indicates that current ecological restoration planning has limitations in improving the wetland landscape patterns. In the future, it is necessary to formulate systematic wetland landscape patterns restoration planning that covers the overall area according to the evolutionary trend of wetlands.


Asunto(s)
Ecosistema , Humedales , Humanos , Ciudades , Conservación de los Recursos Naturales/métodos , Monitoreo del Ambiente/métodos , China
16.
Nano Lett ; 20(4): 2279-2287, 2020 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-31846340

RESUMEN

Full exploitation of graphene's superior properties requires the ability to precisely control its morphology and edge structures. We present such a structure-tailoring approach via controlled atom removal from graphene edges. With the use of a graphitic-carbon-capped tungsten nanoelectrode as a noncontact "milling" tool in a transmission electron microscope, graphene edge atoms approached by the tool tip are locally evaporated, thus allowing a freestanding graphene sheet to be tailored with high precision and flexibility. A threshold for the tip voltage of 3.6 ± 0.4 V, independent of polarity, is found to be the determining factor that triggers the controlled etching process. The dominant mechanisms involve weakening of carbon-carbon bonds through the interband excitation induced by tunneling electrons, assisted with a resistive-heating effect enhanced by high electric field, as elaborated by first-principles calculations. In addition to the precise shape and size control, this tip-based method enables fabrication of graphene edges with specific chiralities, such as "armchair" or "zigzag" types. The as-obtained edges can be further "polished" to become entirely atomically smooth via edge evaporation/reconstruction induced by in situ TEM Joule annealing. We finally demonstrate the potential of this technique for practical uses through creating a graphene-based point electron source, whose field emission characteristics can effectively be tuned via modifying its geometry.

17.
BMC Med Genet ; 18(1): 15, 2017 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-28196537

RESUMEN

BACKGROUND: Hemophagocytic lymphohistocytosis (HLH) is a rare but fatal hyperinflammatory syndrome caused by uncontrolled proliferation of activated macrophages and T lymphocytes secreting high amounts of inflammatory cytokines. Genetic defect is a common cause of HLH. HLH is complicated to be diagnosed as there are many common symptoms with other disorders. CASE PRESENTATION: Here we report on an HLH case caused by 1 bp deletion in gene SH2D1A. Patient was a 3-years-old boy and had fever for more than 8 days. Splenomegaly and hemophagocytosis in bone marrow were observed in examination. The results of the blood analysis suggested the diagnosis of HLH. Genetic test based on high throughput amplicon sequencing was then conducted by targeting all six known HLH-causing genes simultaneously. It took only one single day to accomplish the amplicon sequencing library preparation, sequencing and data analysis. Finally, a novel 1 bp deletion in gene SH2D1A was discovered. The result was also confirmed by Sanger sequencing. The result of the genetic test served as a good basis for further diagnosis of HLH. CONCLUSION: This is the first case that the disease-causing genetic defect of HLH was quickly determined by high throughput amplicon sequencing. This diagnosis was also confirmed by Sanger sequencing and cross-validated by blood analysis and other clinical criteria. This case suggests that genetic test based on amplicon sequencing is a powerful tool for diagnosis of HLH and other diseases caused by genetic defect.


Asunto(s)
Linfohistiocitosis Hemofagocítica/genética , Proteína Asociada a la Molécula de Señalización de la Activación Linfocitaria/genética , Secuencia de Bases , Médula Ósea/patología , Preescolar , ADN/química , ADN/aislamiento & purificación , ADN/metabolismo , Exones , Eliminación de Gen , Pruebas Genéticas , Humanos , Linfohistiocitosis Hemofagocítica/diagnóstico , Masculino , Análisis de Secuencia de ADN
18.
Pak J Pharm Sci ; 30(4(Suppl.)): 1497-1500, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29044004

RESUMEN

To investigate the effect of bilateral oophorectomy on bone mineral density, body composition and sex hormone of peri-menopause women. 33 cases of peri-menopause women patients performed bilateral oophorectomy were chosen from xxx gynaecology and obstetrics department of xxx hospital from January 1st,2014 to Dec31th, 2014. And the 33 cases were taken as ovariectomy group. 35 women who were the naturally postmenopausal after menopause collected in clinic and in the same period with the patients of ovariectomy group were taken in control group. American GE-Lunar-Prodigy dual energy X-ray absorptiometry and chemiluminescence method were employed to detect the bone mineral density, fat content, muscle content and sex hormone of the patients in both groups at the 6th and 12th month after menostasis. There was no statistical significance on the comparative difference of bone mineral density, fat content and muscle content at the 6th and 12th month after menostasis between both groups, P>0.05. At the 6th month after menostasis, the estradiol (E2) level in ovariectomy group was significantly lower than that of control group [(14.79±22.17)U/L vs (32.74±31.02U/L)], P<0.05; at the 12th month after menostasis, it had the statistical significance for the comparative difference between the level of E2 and and follicle-stimulating hormone (FSH) in ovariectomy group and that in control group, E2: (8.09±4.38)U/L vs (25.92±3.53)U/L; FSH: (64.88±18.39)U/L vs (40.69±31.63)U/L], P<0.05. the change of E2 and FSH were the main symptom of peri-menopausal women within 12 months after bilateral oophorectomy, the decrease of E2 level had no effect on bone mineral density, fat content and muscle content.


Asunto(s)
Composición Corporal , Densidad Ósea , Estradiol/sangre , Hormona Folículo Estimulante Humana/sangre , Ovariectomía , Perimenopausia/sangre , Absorciometría de Fotón , Adiposidad , Factores de Edad , Biomarcadores/sangre , Índice de Masa Corporal , Estudios de Casos y Controles , Femenino , Humanos , Persona de Mediana Edad , Ovariectomía/efectos adversos , Factores de Tiempo , Resultado del Tratamiento
19.
BMC Cardiovasc Disord ; 16: 1, 2016 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-26728597

RESUMEN

BACKGROUND: In the initiation and maintenance of arrhythmia, inflammatory processes play an important role. IL-2 is a pro-inflammatory factor which is associated with the morbidity of arrhythmias, however, how IL-2 affects the cardiac electrophysiology is still unknown. METHODS: In the present study, we observed the effect of IL-2 by qRT-PCR on the transcription of ion channel genes including SCN2A, SCN3A, SCN4A, SCN5A, SCN9A, SCN10A, SCN1B, SCN2B, SCN3B, KCNN1, KCNJ5, KCNE1, KCNE2, KCNE3, KCND3, KCNQ1, KCNA5, KCNH2 and CACNA1C. Western blot assays and electrophysiological studies were performed to demonstrate the effect of IL-2 on the translation of SCN3B/scn3b and sodium currents. RESULTS: The results showed that transcriptional level of SCN3B was up-regulated significantly in Hela cells (3.28-fold, p = 0.022 compared with the control group). Consistent results were verified in HL-1 cells (3.73-fold, p = 0.012 compared with the control group). The result of electrophysiological studies showed that sodium current density increased significantly in cells which treated by IL-2 and the effect of IL-2 on sodium currents was independent of SCN3B (1.4 folds, p = 0.023). Western blot analysis showed IL-2 lead to the significantly increasing of p53 and scn3b (2.1 folds, p = 0.021 for p53; 3.1 folds, p = 0.023 for scn3b) in HL-1 cells. Consistent results were showed in HEK293 cells using qRT-PCR analysis (1.43 folds for P53, p = 0.022; 1.57 folds for SCN3B, p = 0.05). CONCLUSIONS: The present study suggested that IL-2, may play role in the arrhythmia by regulating the expression of SCN3B and sodium current density.


Asunto(s)
Interleucina-2/farmacología , Potenciales de la Membrana/efectos de los fármacos , Miocitos Cardíacos/efectos de los fármacos , Canales de Potasio con Entrada de Voltaje/efectos de los fármacos , Sodio/metabolismo , Subunidad beta-3 de Canal de Sodio Activado por Voltaje/efectos de los fármacos , Canales de Calcio/efectos de los fármacos , Canales de Calcio/genética , Regulación de la Expresión Génica , Células HEK293 , Células HeLa , Humanos , Miocitos Cardíacos/metabolismo , Técnicas de Placa-Clamp , Canales de Potasio con Entrada de Voltaje/genética , ARN Mensajero/efectos de los fármacos , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Subunidad beta-3 de Canal de Sodio Activado por Voltaje/genética , Canales de Sodio Activados por Voltaje/efectos de los fármacos , Canales de Sodio Activados por Voltaje/genética
20.
Pediatr Cardiol ; 37(8): 1548-1561, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27567908

RESUMEN

The nuclear factor of activated T lymphocytes (NFATC1) signaling has been demonstrated to play important roles in cardiac valve and septal development. Genetic variants in genes involved in NFATC1 signaling may affect their expression and promote the formation of congenital heart disease (CHD). The goal of this study was to investigate the associations of single nucleotide polymorphism (SNP) in seven genes (NFATC1, VEGFR, VEGF, RANKL, FGFR1, BCL-6 and ZNRD1) with the risk of CHD. Twenty-nine polymorphisms were genotyped by using MassARRAY RS1000 platform in 277 CHD child patients and 293 controls from the Henan Province in China. Fours SNPs were excluded for the association analysis because of deviation from the Hardy-Weinberg equilibrium. Of the 25 SNPs, only two were found to be significantly associated with increased CHD risk after Bonferroni correction (RANKL, rs4531631: homozygous, AA vs. GG; OR 2.38, 95 % CI 1.40-4.07, p = 0.001; recessive, AA vs. AG + GG; OR 2.54, 95 % CI 1.53-4.22, p = 0.0003; FGFR1, rs13317: recessive, CC vs. CT + TT; OR 2.06, 95 % CI 1.30-3.25, p = 0.00196). Our findings suggest rs4531631 and rs13317 may be potential biomarkers for genetic diagnosis and treatment of CHD.


Asunto(s)
Polimorfismo de Nucleótido Simple , Pueblo Asiatico , Estudios de Casos y Controles , China , Predisposición Genética a la Enfermedad , Genotipo , Cardiopatías Congénitas , Humanos , Factores de Transcripción NFATC
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