47 research outputs found
Novel Zinc Finger Transcription Factor ZFP580 Facilitates All-Trans Retinoic Acid -Induced Vascular Smooth Muscle Cells Differentiation by Rarα-Mediated PI3K/Akt and ERK Signaling
Background/Aims: Phenotypic switching of vascular smooth muscle cells (VSMC) plays a vital role in the development of vascular diseases. All-trans retinoic acid (ATRA) is known to regulate VSMC phenotypes. However, the underlying mechanisms remain completely unknown. Here, we have investigated the probable roles and underlying mechanisms of the novel C2H2 zinc finger transcription factor ZFP580 on ATRA-induced VSMC differentiation. Methods: VSMCs were isolated, cultured, and identified. VSMCs were infected with an adenovirus encoding ZFP580 or Ad-siRNA to silence ZFP580. The expression levels of ZFP580, SMα-actin, SM22α, SMemb, RARα, RARβ, and RARγ were assayed by Q-PCR and western blot. A rat carotid artery injury model and morphometric analysis of intimal thickening were also used in this study. Results: ATRA caused a significant reduction of VSMC proliferation and migration in a doseand time-dependent manner. Moreover, it promoted VSMC differentiation by enhancing expression of differentiation markers and reducing expression of dedifferentiation markers. This ATRA activity was accompanied by up-regulation of ZFP580, with concomitant increases in RARα expression. In contrast, silencing of the RARα gene or inhibiting RARα with its antagonist Ro41-5253 abrogated the ATRA-induced ZFP580 expression. Furthermore, ATRA binding to RARα induced ZFP580 expression via the PI3K/Akt and ERK pathways. Adenovirusmediated overexpression of ZFP580 promoted VSMC differentiation by enhancing expression of SM22α and SMα-actin and reducing expression of SMemb. In contrast, silencing ZFP580 dramatically reduced the expression of differentiation markers and increased expression of dedifferentiation markers. The classic rat carotid artery balloon injury model demonstrated that ZFP580 inhibited proliferation and intimal hyperplasia in vivo. Conclusion: The novel zinc finger transcription factor ZFP580 facilitates ATRA-induced VSMC differentiation by the RARα-mediated PI3K/Akt and ERK signaling pathways. This might represent a novel mechanism of regulation of ZFP580 by ATRA and RARα, which is critical for understanding the biological functions of retinoids during VSMC phenotypic modulation
Analysis of risk factors and short-term prognostic factors of arrhythmia in patients infected with mild/moderate SARS-CoV-2 Omicron variant
BackgroundComplications, including arrhythmia, following severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection continue to be of concern. Omicron is the mainstream SARS-CoV-2 mutant circulating in mainland China. At present, there are few epidemiological studies concerning the relationship between arrhythmia and Omicron variant infection in mainland China.ObjectivesTo investigate the risk factors of arrhythmia in patients infected with the SARS-CoV-2 Omicron variant and the factors influencing prognosis.MethodsData from 192 Omicron infected patients with symptoms of arrhythmia (AH group) and 100 Omicron infected patients without arrhythmia (Control group) were collected. Patients in the AH group were divided into the good and poor prognosis groups, according to the follow-up results 4–6 weeks after infection. The general and clinical data between the AH and Control groups, and between the good and poor prognosis groups were compared. The variables with differences between the groups were included in the multivariate logistic regression analysis, and the quantitative variables were analyzed by receiver operating characteristic curve to obtain their cut-off values.ResultsCompared with the control group, the body mass index (BMI), proportion of patients with a history of arrhythmia, proportion of antibiotics taken, heart rate, moderate disease severity, white blood cell (WBC) count, and the aspartate aminotransferase, creatine kinase (CK), CK isoenzyme (CK-MB), myoglobin (Mb), high-sensitive troponin I (hs-cTnI), lymphocyte ratio and high sensitivity C-reactive protein (hs-CRP) levels in the AH group were significantly higher (p < 0.05). In addition, obesity (BMI ≥24 kg/m2), fast heart rate (≥100 times/min), moderate disease severity, and WBC, CK-MB and hs-cTnI levels were independent risk factors of arrhythmia for patients with Omicron infection (p < 0.05), and hs-CRP was a protective factor (p < 0.05). Compared with the good prognosis group, the age, proportion of patients with a history of arrhythmia, heart rate, proportion of moderate disease severity, and hs-CRP, CK, Mb and hs-cTnI levels were significantly higher in the poor prognosis group, while the proportion of vaccination was lower in the poor prognosis group (p < 0.05). Advanced age (≥65 years old), proportion of history of arrhythmia, moderate disease severity, vaccination, and hs-CRP, Mb and cTnI levels were independent factors for poor prognosis of patients with arrhythmia (p < 0.05).ConclusionThe factors that affect arrhythmia and the prognosis of patients infected with Omicron include obesity, high heart rate, severity of the disease, age. history of arrhythmia, WBC, hs-CRP, and myocardial injury indexes, which could be used to evaluate and prevent arrhythmia complications in patients in the future
(t,n) multi-secret sharing scheme extended from Harn-Hsu’s scheme
Abstract Multi-secret sharing scheme has been well studied in recent years. In most multi-secret sharing schemes, all secrets must be recovered synchronously; the shares cannot be reused any more. In 2017, Harn and Hsu proposed a novel and reasonable feature in multiple secret sharing, such that the multiple secrets should be reconstructed asynchronously and the recovering of previous secrets do not leak any information on unrecovered secrets. Harn and Hsu also proposed a (t,n) multi-secret sharing scheme that satisfies this feature. However, the analysis on Harn-Hsu’s scheme is wrong, and their scheme fails to satisfy this feature. If one secret is reconstructed, all the other unrecovered secrets can be computed by any t − 1 shareholders illegitimately. Another problem in Harn-Hsu’s work is that the parameters are unreasonable which will be shown as follows. In this paper, we prove the incorrectness of Harn-Hsu’s scheme and propose a new (t,n) multi-secret sharing scheme which is extended from Harn-Hsu’s scheme; our proposed scheme satisfies the feature introduced by Harn and Hsu
Electrochemical performance improvement and its mechanism analyses on Li-ion battery cathode LiNi1/3Co1/3Mn1/3O2 by surface coating
Electrochemical performance improvement and its mechanism analyses on Li-ion battery cathode LiNi1/3Co1/3Mn1/3O2 by surface coating
Parallel Implementation of the Auxiliary Power System Model of the Electric Locomotive for Hardware-in-the-loop Simulation
International audienceHardware-in-the-loop simulation (HiLs) is an enabling technology for analyzing and testing the control unit of high power electronic system. However, the main difficulty remains in the design of a HiLs platform for a control unit with a complex electronic system. With the attempt to improve this issue, this paper presents the HiLs setup utilizing the dSPACE simulator under the background of the auxiliary power system of the electric locomotive. A massive parallel implementation approach for modeling the auxiliary power system is proposed for the implementation on field programmable gate arrays (FPGAs). The proposed method exploits the large response time of the auxiliary model to: 1) decouple the complex system into independent sub-systems, 2) partition the AC machine model solution from the rest power electronic system using the FPGA/CPU co-mix structure, and 3) adopt nanoseconds range simulation time-step. The whole HIL system can be used to evaluate both the hardware and software performance of the physical auxiliary control unit (ACU). The real time simulation results under steady-state and transient conditions demonstrate modeling accuracy and provide detailed insight into the development of this electrical powertrain
Low charge overpotentials in lithium–oxygen batteries based on tetraglyme electrolytes with a limited amount of water
High charge overpotentials are a great challenge for the realization of lithium–oxygen batteries. Here, we construct a Li–O2 battery system by introducing a limited amount of water into tetraglyme based electrolytes and electrolytic MnO2 (EMD) and Ru supported on Super P as cathodes for Li–O2 batteries. This results in low charge potentials of around 3.2 V, corresponding to overpotentials of 0.24 V, and outstanding rate capability and cycling performance
Wide-temperature rechargeable Li metal batteries enabled by an in-situ fabricated composite gel electrolyte with a hierarchical structure
Lithium metal batteries (LMBs) are well recognized as promising next-generation high energy density batteries, but the uncontrollable Li dendrites growth and the volatilization/gas production of electrolytes, which become extremely worse at low and high temperatures, restrict their practical utilizations. In this work, a hierarchically structured polymerized gel electrolyte (HGE), which was composed of an inorganic (LixGa86In14 alloy and LiCl salt)/organic (polymerized tetrahydrofuran (THF)) hybrid layer and the bulk polymerized THF electrolyte, was proposed to achieve a steady performance of LMBs over a wide temperature range of -20-55 °C. The HGE fabrication can be completed within assembled cells with a simultaneously occurring replacement-polymerization-alloying reaction, which helps decrease the interfacial resistance and enhance the stability and ion diffusion under both low and high temperatures. The use of THF with low polarity also ensures high ion conductivity under low temperatures. With such HGE, the Li symmetric cells showed low overpotential under 10 mA/cm2 with a capacity of 10 mAh/cm2 over a 1200 h cycling, and the full cell coupled with Li4Ti5O12 demonstrated high capacity retention over 5000 cycles at room temperature. Besides, the symmetric cells showed low overpotentials of 12 mV at 55 °C and 80 mV at -20 °C at 2 mA/cm2 after a 1000 h cycling, and the full cell revealed the high capacity retention of 93.5% at 55 °C and 88.8% at -20 °C after 1500 cycles under a high current density of 1000 mA/g. This work shows a hierarchically structured polymerized electrolyte design for advanced Li batteries workable under broad temperatures
FPGA based real-time simulation of high frequency soft-switching circuit using time-domain analysis
International audienceOne of the main keys for modern high efficiency power converters intended for traction applications is implementation of soft-switching technology. Moreover, its control technologies seeks to increase the power density with high frequency. However, this kind of architecture, involving high frequency resonance, is too complex for the real-time simulation with a limited bandwidth. This paper proposes a reduced-order model for this soft-switching circuit by time-domain analysis approach which exhibits a valuable characteristic for the realtime simulation. A variable matrix and subsystem methods are used to solve interface voltages/current from the torn system. Successful implementation of the proposed model on a field programmable gate array (FPGA) device is reported and its application for traction power supply system is implemented with a hardware in the loop (HIL) test. Fixed point operators are used to ensure good accuracy and low computational latency. Comparison between the experiment results and tractionauxiliary analysis shows its stability