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1.
Medicine (Baltimore) ; 100(20): e25928, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34011065

RESUMO

ABSTRACT: Bilateral kidney damage in hypertensive patients is not parallel. Angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACEI/ARB), as a commonly used antihypertensive drug, could protect kidney function and delay its deterioration. Most studies focused on overall renal function, but the researches on split renal function (SRF) are rare. We investigated the effects of ACEI/ARB on the SRF in patients with primary hypertension.Patients with primary hypertension (n = 429; male: 213; female: 216) admitted to our department between January 2014 and December 2016 were included in this study. The glomerular filtration rate (GFR) of split and total renal function were determined using diethylenetriaminepentaacetic acid tagged with 99mTc renal dynamic imaging method. For the same patient, the side with high GFR was considered as higher GFR kidney, whereas that with a low GFR was considered as lower GFR kidney. The split function score (Q value) was utilized to evaluate the differences of bilateral renal function. The patients were divided into 3 groups based on the Q values (Group 1, Q value <5%; Group 2, Q value of 5%-10%; Group 3, Q value ≥10%). All the patients received antihypertensive therapy based on ACEI/ARB. The renal dynamic imaging was performed in the 1-year follow-up to investigate the changes of the SRF.Compared with the baseline level, significant decline was noticed in the serum creatinine (Scr) in Group 2 and Group 3 (P < .05). The cystatin C in Group 3 showed significant decline (P < .05). Compared with the baseline, there was significant decline in the Q value in Group 2, whereas the GFR of lower GFR kidney showed significant increase (P < .05). No statistical differences were noticed in the Q value and split GFR in Group 1 and Group 3 (P > .05).In primary hypertension patients, ACEI/ARB therapy could improve the SRF of lower GFR kidney in the presence of certain differences between the SRF. As a result, the SRF difference was reduced. In case of Q value in a range of 5% to 10%, ACEI/ARB could improve the renal function effectively. It may be significant for the design of antihypertensive drugs.


Assuntos
Antagonistas de Receptores de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Hipertensão/tratamento farmacológico , Rim/efeitos dos fármacos , Insuficiência Renal/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste/administração & dosagem , Creatinina/sangue , Cistatina C/sangue , Feminino , Seguimentos , Taxa de Filtração Glomerular/efeitos dos fármacos , Taxa de Filtração Glomerular/fisiologia , Humanos , Hipertensão/sangue , Hipertensão/complicações , Rim/diagnóstico por imagem , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Insuficiência Renal/sangue , Insuficiência Renal/diagnóstico , Insuficiência Renal/etiologia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Resultado do Tratamento
2.
Nonlinear Dyn ; : 1-14, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32836803

RESUMO

In this paper, a SEIR epidemic model for the COVID-19 is built according to some general control strategies, such as hospital, quarantine and external input. Based on the data of Hubei province, the particle swarm optimization (PSO) algorithm is applied to estimate the parameters of the system. We found that the parameters of the proposed SEIR model are different for different scenarios. Then, the model is employed to show the evolution of the epidemic in Hubei province, which shows that it can be used to forecast COVID-19 epidemic situation. Moreover, by introducing the seasonality and stochastic infection the parameters, nonlinear dynamics including chaos are found in the system. Finally, we discussed the control strategies of the COVID-19 based on the structure and parameters of the proposed model.

3.
Rev Sci Instrum ; 91(6): 064701, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32611026

RESUMO

In this paper, a single-well model based on the piecewise function and classical bistable stochastic resonance (CBSR) is proposed. The steady state probability density of particles and mean first passage time in the model are calculated. The output characteristics and performance of the proposed model are analyzed through numerical simulation. On the basis of CBSR and the proposed model, an adaptive system is established (ACSSR) to generate the highest gain of signal-to-noise ratio (SNRg). Finally, the effectiveness of ACSSR in weak signal detection is verified with both simulated and experimental input signals. The results indicate that the ACSSR could detect the defect signal correctly and improve the SNRg.

4.
Entropy (Basel) ; 21(1)2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33266743

RESUMO

Research on fractional-order discrete chaotic systems has grown in recent years, and chaos synchronization of such systems is a new topic. To address the deficiencies of the extant chaos synchronization methods for fractional-order discrete chaotic systems, we proposed an improved particle swarm optimization algorithm for the parameter identification. Numerical simulations are carried out for the Hénon map, the Cat map, and their fractional-order form, as well as the fractional-order standard iterated map with hidden attractors. The problem of choosing the most appropriate sample size is discussed, and the parameter identification with noise interference is also considered. The experimental results demonstrate that the proposed algorithm has the best performance among the six existing algorithms and that it is effective even with random noise interference. In addition, using two samples offers the most efficient performance for the fractional-order discrete chaotic system, while the integer-order discrete chaotic system only needs one sample.

5.
PLoS One ; 13(9): e0202558, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30180194

RESUMO

There is considerable interest in analyzing the complexity of electroencephalography (EEG) signals. However, some traditional complexity measure algorithms only quantify the complexities of signals, but cannot discriminate different signals very well. To analyze the complexity of epileptic EEG signals better, a new multiscale permutation Rényi entropy (MPEr) algorithm is proposed. In this algorithm, the coarse-grained procedure is introduced by using weighting-averaging method, and the weighted factors are determined by analyzing nonlinear signals. We apply the new algorithm to analyze epileptic EEG signals. The experimental results show that MPEr algorithm has good performance for discriminating different EEG signals. Compared with permutation Rényi entropy (PEr) and multiscale permutation entropy (MPE), MPEr distinguishes different EEG signals successfully. The proposed MPEr algorithm is effective and has good applications prospects in EEG signals analysis.


Assuntos
Algoritmos , Eletroencefalografia , Epilepsia/fisiopatologia , Análise de Variância , Interpretação Estatística de Dados , Entropia , Humanos , Análise de Sistemas
6.
Entropy (Basel) ; 20(8)2018 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-33265645

RESUMO

Designing a chaotic system with infinitely many attractors is a hot topic. In this paper, multiscale multivariate permutation entropy (MMPE) and multiscale multivariate Lempel-Ziv complexity (MMLZC) are employed to analyze the complexity of those self-reproducing chaotic systems with one-directional and two-directional infinitely many chaotic attractors. The analysis results show that complexity of this class of chaotic systems is determined by the initial conditions. Meanwhile, the values of MMPE are independent of the scale factor, which is different from the algorithm of MMLZC. The analysis proposed here is helpful as a reference for the application of the self-reproducing systems.

7.
Entropy (Basel) ; 20(11)2018 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33266567

RESUMO

This paper presents an improved cryptanalysis of a chaos-based image encryption scheme, which integrated permutation, diffusion, and linear transformation process. It was found that the equivalent key streams and all the unknown parameters of the cryptosystem can be recovered by our chosen-plaintext attack algorithm. Both a theoretical analysis and an experimental validation are given in detail. Based on the analysis of the defects in the original cryptosystem, an improved color image encryption scheme was further developed. By using an image content-related approach in generating diffusion arrays and the process of interweaving diffusion and confusion, the security of the cryptosystem was enhanced. The experimental results and security analysis demonstrate the security superiority of the improved cryptosystem.

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