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ETHNOPHARMACOLOGICAL RELEVANCE: Diabetic retinopathy (DR) is a prevalent microvascular complication of diabetes. Chinese medicine believes that kidney deficiency and blood stasis are significant pathogenesis of DR. A characteristic therapeutic approach for this pathogenesis is the kidney-tonifying and blood-activating method. By literature retrieval from several databases, we methodically summarized the commonly used kidney-tonifying and blood-activating herbs for treating DR, including Lycii Fructus, Rehmanniane Radix Praeparata, and Corni Fructus with the function of nourishing kidney; Salvia Miltiorrhizae Radix et Rhizoma with the function of enhancing blood circulation; Rehmanniae Radix with the function of nourishing kidney yin; and Astragali Radix with the function of tonifying qi. It has been demonstrated that these Chinese herbs described above, by tonifying the kidney and activating blood circulation, significantly improve the course of DR. AIM OF THE STUDY: Through literature research, to gain a thorough comprehension of the pathogenesis of DR. Simultaneously, through the traditional application analysis, modern pharmacology research and network pharmacology analysis of kidney-tonifying and blood-activating herbs, to review the effectiveness and advantages of kidney-tonifying and blood-activating herbs in treating DR comprehensively. MATERIALS AND METHODS: PubMed, the China National Knowledge Infrastructure (CNKI), and Wanfang Data were used to filter the most popular herbs for tonifying kidney and activating blood in the treatment of DR. The search terms were "diabetic retinopathy" and "tonifying kidney and activating blood". Mostly from 2000 to 2023. Network pharmacology was applied to examine the key active components and forecast the mechanisms of kidney-tonifying and blood-activating herbs in the treatment of DR. RESULTS: Kidney deficiency and blood stasis are the pathogenesis of DR, and the pathogenesis is linked to oxidative stress, inflammation, hypoxia, and hyperglycemia. Scientific data and network pharmacology analysis have demonstrated the benefit of tonifying kidney and activating blood herbs in treating DR through several channels, multiple components, and multiple targets. CONCLUSIONS: This review first presents useful information for subsequent research into the material foundation and pharmacodynamics of herbs for tonifying kidney and activating blood, and offers fresh insights into the treatment of DR.
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Diabetes Mellitus , Retinopatia Diabética , Medicamentos de Ervas Chinesas , Humanos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Retinopatia Diabética/tratamento farmacológico , Medicina Tradicional Chinesa , Raízes de Plantas , Rim , Diabetes Mellitus/tratamento farmacológicoRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Diabetic retinopathy (DR) is one of the most severe complications of diabetes mellitus, diabetes belongs to the category of "emaciation-thirst disease" in traditional Chinese medicine (TCM). Bushen Huoxue Prescription (BHP) is composed of traditional Chinese materia medica, which has therapeutic effects on DR and early diabetic retinal edema (EDRE). However, the therapeutic mechanism is unclear. AIM OF THE STUDY: Exploring the mechanism of BHP against EDRE. METHODS: Feeding Sprague Dawley (SD) rats a high-fat, high-sugar diet as well as providing intraperitoneal injections of streptozotocin (STZ) to promote inner blood-retinal barrier (iBRB) damage that can trigger EDRE, evaluating the therapeutic effect of BHP by the level of expressiveness of TJ proteins (ZO-1,Occludin) of the iBRB and the leakage of rhodamine B isothiocyanate (RITC) in the retina. The combination of network pharmacology and metabolomics was employed to study the mechanism of BHP in preventing of EDRE, then four proteins which were closely to the damage of iBRB were chosen for the validation by employing Western Blot (WB). RESULTS: Research of network pharmacology had shown that BHP had efficacy against EDRE by regulating targets such as AKT1, ALB, TNF, PPARG, etc, its potential pathways mainly involving signaling pathways such as HIF-1. In untargeted metabolomics analysis of serum, 15 differential metabolites were identified, with the metabolic pathways focusing on ketone body metabolism and synthesis, sphingolipid metabolism and phenylalanine metabolism. The conclusions of metabolomics and network pharmacology revealed that BHP can treat EDRE by alleviating hypoxia and oxidative stress and exerting protection of the iBRB. Finally, BHP's protection behavior of the iBRB was validated by WB experiments. CONCLUSION: Through integrating pharmacodynamics, network pharmacology and metabolomics, BHP was discovered to have a crucial function in EDRE therapy by preserving the integrity of iBRB. This comprehensive strategy also provided a reasonable way to reveal the multi-components, multi-targets, multi-pathways mechanism of TCM.
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Diabetes Mellitus , Retinopatia Diabética , Medicamentos de Ervas Chinesas , Ratos , Animais , Barreira Hematorretiniana , Ratos Sprague-Dawley , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/metabolismo , Diabetes Mellitus/metabolismoRESUMO
OBJECTIVE: To visualize and analyze the published literature on diabetes mellitus and pyroptosis based on a bibliometric approach, so as to provide a comprehensive picture of the hot research directions and dynamic progress in this field. METHODS: This study was based on the web of science core collection database to conduct a comprehensive search of the published literature in the field of diabetes mellitus and Pyroptosis from January 1985 to August 2022, including the published research literature in this field, as well as a visual analysis of the number of citations, year of publication, journal, author, research institution, country, and research topic. RESULTS: A total of 139 literature on research related to diabetes mellitus and cellular scorch from 2011 to 2022 were retrieved, with a total of 3009 citations and a maximum of 255 citations for a single article, which had a first author Schmid-Burgk, JL The first author of this article is from Germany; among 20 publishing countries, China leads with 100 articles; among 222 publishing institutions, Harbin Medical University leads with 18 articles and 184 citations; among 980 authors, Chen, X from China tops the list of high-impact authors with 5 articles and 29 citations. Among the 98 journals, "CELL DEATH DISEASE" ranked first in both volume and high-impact journals with 4 articles and 29 citations. Among 349 keywords, "pyroptosis" ranked first with a cumulative frequency of 65 times. The cluster analysis was divided into three categories, chronic complications of diabetes mellitus and pyroptosis (67 articles), diabetes mellitus and pyroptosis (60 articles), and diabetes mellitus combined with other diseases and pyroptosis (12 articles), and the number of articles related to diabetes mellitus and its chronic complications increased rapidly from 2019, among which, diabetic cardiomyopathy (27 articles) had the highest number of articles. CONCLUSIONS: Based on a comprehensive analysis of published literature in the field of diabetes mellitus and pyroptosis from 2011 to 2022, this study achieved a visual analysis of studies with significant and outstanding contributions to the field, thus framing a picture showing the development and changes in the field. At the same time, this study provides research information and direction for clinicians and investigators to conduct diabetes mellitus and pyroptosis-related research in the future.
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Bibliometria , Diabetes Mellitus , Humanos , Alemanha , ChinaRESUMO
PURPOSE: To evaluate the choroidal vascularity index (CVI) in different types of central serous chorioretinopathy (CSC), healthy control eyes, and fellow eyes. METHODS: Relevant studies published up to January 2023 were identified by searching multiple databases, including PubMed, Embase, Web of Science, Cochrane Library, and China National Knowledge Infrastructure (CNKI). Studies investigating the difference in CVI between CSC and control eyes were included. Data from these studies were analyzed using Stata (version 17) software. Weighted mean difference (WMD) and 95% confidence interval (95%CI) were calculated for the CVI in CSC eyes, control eyes, and fellow eyes. RESULTS: The meta-analysis included 15 studies, with 213 acute CSC eyes, 153 chronic CSC eyes, 92 uncategorized CSC eyes, 40 resolved CSC eyes, 409 eyes of normal healthy controls, and 318 fellow eyes. The result revealed that CVI was higher in acute CSC eyes (WMD = 5.40, 95%CI = 2.36-8.44, P = 0.001) compared to control eyes. Also, CVI in chronic CSC eyes was higher than in control eyes (WMD = 1.26, 95%CI = 0.03-2.49, p = 0.046). The fellow eyes of acute CSC had a higher CVI when compared to control eyes (WMD = 2.53, 95%CI = 0.78-4.28, p = 0.005). There was no significant difference in CVI between acute and chronic CSC eyes (WMD = 0.75, 95%CI = -0.31-1.82, P = 0.167). In the sub-analysis based on the area selected for CVI calculation, the WMDs in the whole image subgroups were lower than the main analysis for the comparisons of fellow eyes of acute CSC and control eyes, acute CSC eyes and control eyes, and acute CSC eyes and fellow eyes. In the macular area subgroups, the WMDs were higher than in the whole image subgroups, suggesting a potential regional variation of CVI in CSC eyes. CONCLUSIONS: The results demonstrated that CVI is increased in CSC eyes and fellow eyes of acute CSC. There is no significant difference in CVI between acute and chronic CSC eyes. The area selected for CVI calculation can influence the outcome, which requires further clinical research to clarify.
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Coriorretinopatia Serosa Central , Humanos , Coriorretinopatia Serosa Central/diagnóstico por imagem , Angiofluoresceinografia/métodos , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Corioide , Estudos RetrospectivosRESUMO
This study aimed to investigate the active components of Bushen Huoxue Prescriptions (BHP), and further clarify the mechanism by the integration of serum pharmacochemistry and serum pharmacology based on spectrum-effect relationship in vivo. In this paper, the components absorbed into serum were analyzed by ultra-high performance liquid chromatography-quadrupole-Exactive Orbitrap-high resolution mass spectrometry (UPLC-Q-Exactive Orbitrap-HRMS). And Müller cells were chosen as target cells to further investigate the mechanism. After cell purification, the well-grown cells were identified by Hematoxylin-eosin staining (HE) staining and immunofluorescence assay, such as glial fibrillary acidic protein (GFAP) and glutamine synthetase (GS). The logarithmic phase cells were divided into normal group, model group and 12 BHP groups. The hyperglycemic and hypoxic model was induced by 50 mmol/L glucose and 1 mmol/L sodium disulfite. Enzyme-linked immunesorbnent assay (ELISA) was used to detect the expressions of five factors closely related to DR, named vascular endothelial growth factor (VEGF), hypoxia-inducible factor1-alpha (HIF-1α), protein kinase C-ß (PKC-ß), angiopoietin-2 (ANG-2) and transforming growth factor-ß (TGF-ß). Finally, the spectrum-effect relationship was investigated to screen the active components of BHP by partial least squares regression (PLSR). The results showed that 83 metabolic components, containing 30 prototypes and 53 metabolites were found in BHP serum. 12 characteristic common peaks were chosen to establish spectrum-effect relationship. Significantly, all the 12 BHP serum exhibited stronger inhibition on the expression of VEGF, PKC-ß, and ANG-2, and the expression of VEGF, PKC-ß, ANG-2 was chosen to establish the spectrum-effect relationship in vivo. The results of PLSR revealed that the content of methylation and sulfuration of caffeic acid, dehydroxylation and sulfation of Danshensu, daidzein, O-demethylangolanolin, cryptotanshinone, tanshinone IIA and protopanaxatriol were inversely correlated with VEGF expression of Müller cells; the areas of dihydrocaffeic acid, methylation and sulfuration of caffeic acid, dehydroxylation and sulfation of Danshensu, daidzein, cryptotanshinone, tanshinone IIA were negative correlation with the expression of PKC-ß; while the coefficient of hydroxytyrosol sulfation, R-equol, O-demethylangolanolin, dihydrotanshinone IIA, hydrated cryptotanshinone, protopanaxatriol showed negative correlation with the expression of ANG-2. The above results indicated that cryptotanshinone, tanshinone IIA, daidzein and protopanaxatriol need be focused in our future research. In addition, this research idea provides feasible ways to investigate and determine pharmacodyamic material basis and screen the Q-markers of TCM and its formulas.
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Diabetes Mellitus , Retinopatia Diabética , Humanos , Retinopatia Diabética/metabolismo , Fator A de Crescimento do Endotélio VascularRESUMO
Silicon-containing polyester from tetramethoxysilane, ethylene glycol, and o-Phthalic anhydride were used as encapsulating materials for silicon nano powders (SiNP) via electrospinning, with Polyacrylonitrile (PAN) as spinning additives. In the correct quantities, SiNP could be well encapsulated in nano fibers (200-400 nm) using scanning electron microscopy (SEM). The encapsulating materials were then carbonized to a Si-O-C material at 755 °C (Si@C-SiNF-5 and Si@C-SiNF-10, with different SiNP content). Fiber structure and SiNP crystalline structure were reserved even after high-temperature treatment, as SEM and X-ray diffraction (XRD) verified. When used as lithium ion battery (LIB) anode materials, the cycling stability of SiNPs increased after encapsulation. The capacity of SiNPs decreased to ~10 mAh/g within 30 cycles, while those from Si@C-SiNF-5 and Si@C-SiNF-10 remained over 500 mAh/g at the 30th cycle. We also found that adequate SiNP content is necessary for good encapsulation and better cycling stability. In the anode from Si@C-SiNF-10 in which SiNPs were not well encapsulated, fibers were broken and pulverized as SEM confirmed; thus, its cycling stability is poorer than that from Si@C-SiNF-5.
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Increasing evidences suggest that miRNAs play a key role in the occurrence and progression of many complex human diseases. Therefore, targeting dysregulated miRNAs with small molecule drugs in the clinical has become a new treatment. Nevertheless, it is high cost and time-consuming for identifying miRNAs-targeted with drugs by biological experiments. Thus, more reliable computational method for identification associations of drugs with miRNAs urgently need to be developed. In this study, we proposed an efficient method, called GNMFDMA, to predict potential associations of drug with miRNA by combining graph Laplacian regularization with non-negative matrix factorization. We first calculated the overall similarity matrices of drugs and miRNAs according to the collected different biological information. Subsequently, the new drug-miRNA association adjacency matrix was reformulated based on the K nearest neighbor profiles so as to put right the false negative associations. Finally, graph Laplacian regularization collaborative non-negative matrix factorization was used to calculate the association scores of drugs with miRNAs. In the cross validation, GNMFDMA obtains AUC of 0.9193, which outperformed the existing methods. In addition, case studies on three common drugs (i.e., 5-Aza-CdR, 5-FU and Gemcitabine), 30, 31 and 34 of the top-50 associations inferred by GNMFDMA were verified. These results reveal that GNMFDMA is a reliable and efficient computational approach for identifying the potential drug-miRNA associations.
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ETHNOPHARMACOLOGICAL RELEVANCE: Chinese herbal medicines have complex chemical composition; therefore, revealing the effective substances of Chinese herbal medicine becomes a prerequisite for scientific elucidation of the mechanism of action of Bushen Huoxue Prescription (BHP) against diabetic retinopathy (DR) and the development of new drugs. AIM OF THE STUDY: The Chinmedomics technique was used to evaluate the pharmacodynamic ingredients and mechanism of action of BHP against DR rats. MATERIALS AND METHODS: The overall physiological condition of the rats, including body weight, blood glucose, inflammatory factor levels, histological staining, and urine metabolic profile were examined to evaluate the model and its effects. The chemical composition of BHP in vivo and ex vivo was fully analyzed utilizing UPLC-Q-Exactive Orbitrap MS in conjunction with TCM serum pharmacochemistry. Finally, correlation analysis between biomarkers, and serum migration components was used to identify Quality markers (Q-markers) that were significantly associated with effectiveness. RESULTS: The UPLC-Q-Exactive Orbitrap MS platform was used to identify a total of 29 chemicals in serum, 17 of which were highly linked with effectiveness and can be potentially employed as pharmacodynamic substances for BHP against DR. In addition, 14 biomarkers related to galactose metabolism, starch and sucrose metabolism, pantothenate and CoA biosynthesis, glycine, serine, and threonine metabolism were identified. These pathways reveal that DR may be inextricably linked to levels of oxidative stress and inflammation in the organism. Finally, five active ingredients were identified as potential Q-markers of BHP against DR, namely ajugol, protocatechuic acid, tanshinone IIA, panaxatriol and puerarin. CONCLUSION: This study successfully clarified the efficacy and Q-markers of BHP through the Chinmedomics strategy, which is of great significance in determining the quality standards of BHP.
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Diabetes Mellitus , Retinopatia Diabética , Medicamentos de Ervas Chinesas , Ratos , Animais , Medicamentos de Ervas Chinesas/farmacologia , Retinopatia Diabética/tratamento farmacológico , Biomarcadores , Prescrições , Diabetes Mellitus/tratamento farmacológicoRESUMO
Accumulating evidences show that circular RNAs (circRNAs) play an important role in regulating gene expression, and involve in many complex human diseases. Identifying associations of circRNA with disease helps to understand the pathogenesis, treatment and diagnosis of complex diseases. Since inferring circRNA-disease associations by biological experiments is costly and time-consuming, there is an urgently need to develop a computational model to identify the association between them. In this paper, we proposed a novel method named KNN-NMF, which combines K nearest neighbors with nonnegative matrix factorization to infer associations between circRNA and disease (KNN-NMF). Frist, we compute the Gaussian Interaction Profile (GIP) kernel similarity of circRNA and disease, the semantic similarity of disease, respectively. Then, the circRNA-disease new interaction profiles are established using weight K nearest neighbors to reduce the false negative association impact on prediction performance. Finally, Nonnegative Matrix Factorization is implemented to predict associations of circRNA with disease. The experiment results indicate that the prediction performance of KNN-NMF outperforms the competing methods under five-fold cross-validation. Moreover, case studies of two common diseases further show that KNN-NMF can identify potential circRNA-disease associations effectively.
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This article investigates the problem of global neural network (NN) tracking control for uncertain nonlinear systems in output feedback form under disturbances with unknown bounds. Compared with the existing NN control method, the differences of the proposed scheme are as follows. The designed actual controller consists of an NN controller working in the approximate domain and a robust controller working outside the approximate domain, in addition, a new smooth switching function is designed to achieve the smooth switching between the two controllers, in order to ensure the globally uniformly ultimately bounded of all closed-loop signals. The Lyapunov analysis method is used to strictly prove the global stability under the combined action of unmeasured states and system uncertainties, and the output tracking error is guaranteed to converge to an arbitrarily small neighborhood through a reasonable selection of design parameters. A numerical example and a practical example were put forward to verify the effectiveness of the control strategy.
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Ocular abnormalities have been reported in association with viral infections, including Long COVID, a debilitating illness caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). This report presents a case of a female patient diagnosed with Acute Macular Neuroretinopathy (AMN) following an Influenza A virus infection during Long COVID who experienced severe inflammation symptoms and ocular complications. We hypothesize that the rare occurrence of AMN in this patient could be associated with the immune storm secondary to the viral infection during Long COVID.
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COVID-19 , Vírus da Influenza A , Viroses , Síndrome dos Pontos Brancos , Humanos , Feminino , SARS-CoV-2 , COVID-19/complicações , Síndrome de COVID-19 Pós-AgudaRESUMO
BACKGROUND: Associations of drugs with diseases provide important information for expediting drug development. Due to the number of known drug-disease associations is still insufficient, and considering that inferring associations between them through traditional in vitro experiments is time-consuming and costly. Therefore, more accurate and reliable computational methods urgent need to be developed to predict potential associations of drugs with diseases. METHODS: In this study, we present the model called weighted graph regularized collaborative non-negative matrix factorization for drug-disease association prediction (WNMFDDA). More specifically, we first calculated the drug similarity and disease similarity based on the chemical structures of drugs and medical description information of diseases, respectively. Then, to extend the model to work for new drugs and diseases, weighted [Formula: see text] nearest neighbor was used as a preprocessing step to reconstruct the interaction score profiles of drugs with diseases. Finally, a graph regularized non-negative matrix factorization model was used to identify potential associations between drug and disease. RESULTS: During the cross-validation process, WNMFDDA achieved the AUC values of 0.939 and 0.952 on Fdataset and Cdataset under ten-fold cross validation, respectively, which outperforms other competing prediction methods. Moreover, case studies for several drugs and diseases were carried out to further verify the predictive performance of WNMFDDA. As a result, 13(Doxorubicin), 13(Amiodarone), 12(Obesity) and 12(Asthma) of the top 15 corresponding candidate diseases or drugs were confirmed by existing databases. CONCLUSIONS: The experimental results adequately demonstrated that WNMFDDA is a very effective method for drug-disease association prediction. We believe that WNMFDDA is helpful for relevant biomedical researchers in follow-up studies.
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Algoritmos , Asma , Humanos , Análise por Conglomerados , Bases de Dados Factuais , Projetos de PesquisaRESUMO
Background: Changes in fundus signs and loss of visual acuity are an important basis for screening and treating diabetic patients with retinopathy, and conventional Western medicine is moderately effective in treating diabetic retinopathy(DR),To systematically evaluate the effectiveness and safety of Chinese herbal compounds(CHCs) in the combined treatment of diabetic retinopathy. Method: Six electronic databases, including PubMed, were searched to screen eligible literature. Randomized controlled trials of non-proliferative diabetic retinopathy(NPDR) were included, in which the control group was treated with conventional Western-based drugs or retinal laser photocoagulation, and the intervention group was treated with CHCs in combination based on the control group.The Cochrane Risk of Bias Assessment Tool was used to evaluate the quality of the literature, and the RevMan 5.4 software was used for statistical analysis. Results: Compared with Conventional group alone,CHCs group was superior at improving clinical efficacy [RR=1.29, 95%CI=(1.23, 1.36),P<0.01] and best corrected visual acuity(BCVA) [MD=0.10,95%CI=(0.09,0.12),P<0.01],it was also superior at reducing the number of microangiomas [MD=-2.37, 95%CI=(-3.26, -1.49),P<0.01], microangioma volume [MD=-4.72, 95%CI=(-5.14, -4.29), P<0.01], hemorrhagic spots [MD=-2.05, 95%CI=(-2.51,-1.59), P<0.01], hemorrhagic area [MD=-0.76, 95%CI=(-1.06, -0.47), P<0.01], hard exudates [MD= -1.86, 95%CI=(-2.43, -1.28), P<0.01], cotton lint spots [MD= -0.93, 95%CI= (-1.31, -0.55), P<0.01], central macular thickness(CMT) [SMD=-1.52, 95%CI=(-1.85, -1.19),P<0.01], Chinese medicine evidence score [SMD=-1.33,95%CI=(-1.58, -1.08),P<0.01], fasting blood glucose (FBG) [SMD=-0.47, 95%CI=(-0.61,-0.33),P<0.01], 2h postprandial blood glucose(2hPBG) [SMD=-0.87, 95% CI=(-1.06, -0.67), P<0.01], glycosylated hemoglobin (HbAlc) [SMD=-0.76, 95%CI=(-1.16, -0.3),P<0.01], total cholesterol(TC) [SMD=-0.33,95%CI=(-0.51,-0.16),P<0.01],and CHCs group with less adverse events occurred [RR=0.46, 95%CI=(0.29, 0.74),P<0.01]. Conclusion: CHCs combined with conventional medicine for NPDR has better clinical efficacy and higher safety, but the above findings need further validation in more large sample, multicenter, and low-bias RCTs due to the limitation of the quality and quantity of included literature. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42022342137.
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Diabetes Mellitus , Retinopatia Diabética , Glicemia , China , Humanos , Fotocoagulação a Laser , Estudos Multicêntricos como Assunto , Acuidade VisualRESUMO
This article investigates the asymptotic tracking control problem for full-state-constrained nonlinear systems with unknown time-varying powers. By introducing a nonlinear state-dependent transformation, a continuous bounded scalar function, and lower and higher powers into adding a power integrator control design, full-state constraints are skillfully handled without imposing frequently used feasibility conditions in traditional barrier Lyapunov function-based methods, and an asymptotic tracking control design is provided. It is proved that all the closed-loop signals are bounded, full-state constraints are not transgressed, and the asymptotic tracking is achieved.
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Redes Neurais de Computação , Dinâmica não LinearRESUMO
This article investigates the tracking control for input and full-state-constrained nonlinear time-delay systems with unknown time-varying powers, whose nonlinearities do not impose any growth assumption. By utilizing the auxiliary control signal and nonlinear state-dependent transformation (NSDT) to counteract the effect of input saturation and cope with full-state constraints, respectively, and then introducing lower and higher powers and Lyapunov-Krasovskii (L-K) functionals in control design together with the adaptive neural-networks (NNs) method, an adaptive neural tracking control design is provided without feasibility conditions. It is proved that NNs approximation is valid, all the closed-loop signals are semiglobally bounded, and input and full-state constraints are not violated.
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Redes Neurais de Computação , Dinâmica não Linear , Simulação por Computador , Estudos de Viabilidade , Projetos de PesquisaRESUMO
This article discusses the adaptive fuzzy asymptotic tracking control for high-order nonlinear time-delay systems with full-state constraints. Fuzzy-logic systems and a separation principle are utilized to relax growth assumptions imposed on unknown nonlinearities. The adverse effect caused by unknown time delays is eliminated by choosing appropriate Lyapunov-Krasovskii functionals. By integrating nonlinear-transformed functions with a key coordinate transformation into the control design and constructing a specific compact set on the initial values of system states, the desired trajectory and parameter estimates, it is rigorously proved that all closed-loop signals are semiglobally bounded, the fuzzy approximation is valid, the full-state constraints are not violated without feasibility conditions on virtual controllers, and asymptotic tracking is achieved. The effectiveness and advantages of this control scheme are confirmed by two examples including a single-link robotic system.
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In this article, an adaptive practical tracking control scheme is presented for full-state constrained high-order nonlinear systems. By skillfully introducing the adaptive gain, nonlinear transformed functions and sign functions into control design, a novel continuous state-feedback controller is constructed without imposing restrictive approximation techniques and feasibility conditions. Under mild assumptions, the boundedness of all the closed-loop signals can be guaranteed, full-state constraints are not transgressed for all time, and the tracking error tends to an arbitrarily small region of zero in a finite time.
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ETHNOPHARMACOLOGICAL RELEVANCE: Diabetic retinopathy (DR) is a kind of complex complication of late diabetes mellitus with high incidence and risk of blindness. Bushen Huoxue Prescription (BHP), which consists of Rehmanniae radix (RR), Salviae miltiorrhizae radix et rhizoma (SMRR), Ginseng radix et rhizome (GRR) and Puerariae lobatae radix (PLR), has an active effect on the treatment of DR. However, the quality markers (Q-markers) of BHP are not entirely clear. PURPOSE: This study aimed to screen the Q-markers of BHP for DR treatment based on the establishment of spectrum-effect relationship and verified experiment. MATERIALS AND METHODS: In this study, 12 BHP samples (S1-S12) for fingerprint analysis and pharmacological evaluation were prepared according to a four-factor and twelve-level uniform design. High performance liquid chromatography-ultraviolet detector-evaporative light scattering detector (HPLC-UV-ELSD) was employed to analyze the fingerprint on the basis of the characteristics of BHP components. The evaluation of sample similarity was carried out by similarity analysis (SA) and hierarchical cluster analysis (HCA). The pharmacological indicators, including expression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1α (HIF-1α) in the retina of Sprague Dawley (SD) rats induced by streptozotocin (STZ), were detected by enzyme-linked immunosorbent assay (ELISA). Besides, the spectrum-effect relationship between common peaks of fingerprints and the pharmacological results was investigated by partial least squares regression (PLSR) and canonical correlation analysis (CCA). The results of spectrum-effect relationship were verified by the expression of VEGF and HIF-1α on primary culture retinal Müller cells induced by hyperglycemia and hypoxia. RESULTS: In the HPLC-UV-ELSD fingerprint, 23 common peaks in UV and 14 common peaks in ELSD were identified. The pharmacological results indicated that the expression of VEGF and HIF-1α in the retina of SD rats was inhibited by 12 BHP samples to varying degrees compared with the model group. Based on SA and heatmap of HCA, S4 and S8 were clearly distinguished from other samples. The results of PLSR and CCA revealed that the contents of puerarin, daidzin, salvianolic acid B and ginsenoside Rb1 were inversely correlated with the expression of VEGF and HIF-1α. Hence, the four compounds may be the main active components to prevent and treat DR. The results of intervention on primary culture retinal Müller cells showed that puerarin, daidzin, salvianolic acid B, and ginsenoside Rb1 can significantly inhibit the expression of VEGF and HIF-1α. CONCLUSIONS: The spectrum-effect relationship of BHP was successfully established, and the Q-markers of BHP for the prevention and treatment of DR were preliminarily confirmed. It provides a feasible method for the research of quality control.
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Biomarcadores , Retinopatia Diabética , Medicamentos de Ervas Chinesas/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Biomarcadores/análise , Biomarcadores/metabolismo , Análise de Correlação Canônica , Quimiometria/métodos , Diabetes Mellitus Experimental/complicações , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/metabolismo , Retinopatia Diabética/prevenção & controle , Células Ependimogliais/efeitos dos fármacos , Células Ependimogliais/metabolismo , Células Ependimogliais/patologia , Controle de Qualidade , Ratos , Ratos Sprague-Dawley , Análise Espectral/métodosRESUMO
An improved spectral reflectance estimation method was developed to transform captured RGB images to spectral reflectance. The novelty of our method is an iteratively reweighted regulated model that combines polynomial expansion signals, which was developed for spectral reflectance estimation, and a cross-polarized imaging system, which is used to eliminate glare and specular highlights. Two RGB images are captured under two illumination conditions. The method was tested using ColorChecker charts. The results demonstrate that the proposed method could make a significant improvement of the accuracy in both spectral and colorimetric: it can achieve 23.8% improved accuracy in mean CIEDE2000 color difference, while it achieves 24.6% improved accuracy in RMS error compared with classic regularized least squares (RLS) method. The proposed method is sufficiently accurate in predicting the spectral properties and their performance within an acceptable range, i.e., typical customer tolerance of less than 3 DE units in the graphic arts industry.
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Colorimetria , Iluminação , AlgoritmosRESUMO
Late blight, caused by the oomycete Phytophthora infestans, is one of the most devastating diseases that results in huge losses of potato crops worldwide. Chitosan as a defence elicitor can induce plant innate immunity against pathogen infection, but the efficiency and specific defence mechanism of chitosan against late blight in potato have not been elaborated. In this study, we demonstrated that the application of chitosan significantly enhanced potato resistance and reduced P. infestans infection in potted potato and in the field. Large-scale transcriptomic analysis suggested that chitosan preferentially activated several important pathways related to the plant defence response. Notably, we revealed that chitosan triggered pattern-triggered immunity responses in potato. Chitosan could trigger pattern recognition receptors to initiate intracellular signalling, and gradually amplify the immune signal. qRT-PCR verification showed that chitosan induced the expression of defence-related genes in potato. Moreover, treatment with chitosan result in Induced Systemic Resistance (ISR) in potato, including an accumulation of plant hormone salicylic acid, increase in the level of phenylalanine ammonia lyase activity and a content decrease of malondialdehyde. These findings help elucidate chitosan-mediated activation of the immune system in potato and provide a potential ecofriendly strategy to control potato late blight in the field.