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1.
Neural Netw ; 168: 350-362, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37797397

RESUMO

Deep learning is vulnerable to backdoor poisoning attacks in which an attacker can easily embed a hidden backdoor into a trained model by injecting poisoned samples into the training set. Many prior state-of-the-art techniques for detecting backdoor poisoning attacks are based on a potential separability assumption. However, current adaptive poisoning strategies can significantly reduce 'distinguishable behavior', making most prior state-of-the-art techniques less effective. In addition, we note that existing detection methods are not practical for multidomain datasets and may leak user privacy because they require and collect clean samples. To address the above issues, we propose a multidomain active defense approach that does not use clean datasets. The proposed approach can generate diverse clean samples from different domains and decouple neural networks round by round using clean samples to disassociate features and labels, making backdoor poisoned samples easier to detect without fitting clean samples. We demonstrate the advantage of our approach through an extensive evaluation of CIFAR10, CelebA, MNIST & MNIST-M, MNIST & USPS & MNIST-M, MNIST & USPS & SVHN and CIFAR10 & Tiny-ImageNet.


Assuntos
Venenos , Redes Neurais de Computação , Privacidade
2.
J Colloid Interface Sci ; 650(Pt B): 1022-1031, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37459726

RESUMO

The kinetic competition between water oxidation/electron extraction processes and recombination behaviors is a key consideration in the development of efficient photoanodes for solar-driven water splitting. Investigating the photogenerated charge behaviors could guide the construction of high-efficiency photoanodes. In this study, the charge carrier kinetics involved in photoelectrochemical water oxidation of PDS/Ti-Fe2O3 were analyzed using surface photovoltage (SPV), transient photovoltage (TPV), short-pulse transient photocurrent (TPC) and photoelectrochemical impedance spectra (PEIS). The TPC results indicate the interfacial electric field introduced by the PDS loading increases the electron extraction and suppresses the bulk recombination, enhancing the spatial separation of photogenerated charges, which is consistent with the SPV and TPV results. Besides, the surface recombination of the back electron (BER) is also attenuated, which enhances the long-lived holes at the surface of PDS/Ti-Fe2O3 photoanode. Similarly, as obtained by PEIS fitting, the loading of PDS accelerates holes transfer at the photoanode/electrolyte interface, and increases the utilization of long-lived holes. In other word, the recombination behaviors of photogenerated charges are restrained both in the bulk and surface of the photoanode after the deposition of PDS, leading to enhanced PEC performance. These findings highlight the importance of understanding charge carrier dynamics in the design of high-efficient photoanodes.

3.
Medicine (Baltimore) ; 102(30): e34500, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37505142

RESUMO

Sarcopenia is an age-related degenerative disease associated with adverse outcomes such as falls, functional decline, weakness, and mortality. Exploring the dynamic evolutionary path and patterns of sarcopenia research topics within a temporal framework from the perspective of strategic coordinate maps and data flow can help identify the development rules of sarcopenia themes. After searching, a total of 16,326 articles were obtained. There are few early research topics, but the development maturity of the topics is high; the number of late research topics continues to increase, showing a trend of diversified development. The differentiation and fusion of the theme evolution path are obvious, and the theme inheritance index is high. The development trend of this research field is promising. The mature and stable professional topics such as "RESISTANCE EXERCISE" and "SURVIVAL" that appeared in the late stage belong to the core topics, while newly emerging topics like "FRACTURES" and "PROTEIN" belong to the marginal topics, indicating that the research on muscle and bone metabolism in the field of sarcopenia has yet to be further in-depth, and the "CANCER" topic is a highly promising research topic with strong development potential.


Assuntos
Fraturas Ósseas , Sarcopenia , Humanos , Bibliometria , Exercício Físico , Músculos
4.
Sensors (Basel) ; 23(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37447916

RESUMO

Linear active disturbance rejection control (LADRC) has been widely used to improve the tracking accuracy and anti-disturbance performance of telescope servo control under disturbances. However, the linear extended state observer (LESO) is sensitive to noise, and its bandwidth is limited by the resonant frequency of the telescope. To enhance the LARDC's ability to attenuate disturbances, a novel cascade anti-disturbance structure (NCADS) with LADRC on the outer speed loop and a nonlinear disturbance observer (NDOB) on the inner current loop is proposed. The NDOB compensates for the dominant disturbance through feedforwarding the q-axis current reference, and the LESO compensates for the residual disturbance on the outer speed loop. First, the NCADS is introduced in a three-closed-loop control framework of PMSM. Then, the design method of the controller for each loop and the NDOB are presented, the parameter-tuning method based on bandwidth is demonstrated, and the convergence of the NDOB is proved. Furthermore, to improve the searching and tracking efficiency of wide-field survey telescopes, the nonlinear tracking differentiator (NTD) was modified to plan the transition process of the position loop, which only needs to set the maximum speed and acceleration of the telescope. Finally, simulations and experiments were performed on a 2.5-m-wide field survey telescope. The experimental results verify that the proposed NCADS method has a better anti-disturbance performance and higher tracking precision than the conventional method, and the improved NTD method does not need to tune parameters and achieved a fast and smooth transition process of the position loop.


Assuntos
Telescópios , Projetos de Pesquisa , Aceleração
5.
J Colloid Interface Sci ; 649: 492-500, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37356150

RESUMO

Ti-ZnFe2O4 photoanode has attracted extensive attention in photoelectrochemical (PEC) water oxidation due to its narrow band gap and good photostability. However, its low efficiency limits its development. Herein, we designed and constructed direct Z-scheme Ti-ZnFe2O4/In2O3 (Ti-ZFO/In2O3) photoanode. Under the interface electric field, photogenerated holes with stronger oxidation capacity on In2O3 are retained to participate in the water oxidation reaction, and the photocurrent density of Ti-ZFO/In2O3 is much higher than that of pure Ti-ZFO, reaching 2.2 mA/cm2 at 1.23 V vs. RHE. Kelvin Probe, steady-state photovoltage spectroscopy (SPV), transient photovoltage spectroscopy (TPV) and in-situ double beam strategy were used to demonstrate the Z-scheme charge transfer mechanism of Ti-ZFO/In2O3 photoanode. Our work provides an effective scheme and technical means for further understanding the mechanism of interfacial charge transfer.

6.
Artigo em Inglês | MEDLINE | ID: mdl-37089718

RESUMO

Objective: From the perspective of metabolomics, this study compares the metabolomics characteristics of feces and urine between children with spleen-deficiency and healthy children to explain the scientific connotation of children with spleen-deficiency susceptibility to digestive system diseases from the metabolic level and provide a scientific basis for further research. Methods: This study included 20 children with spleen-deficiencies and 17 healthy children. Children's symptom scores, height, and weight were recorded in groups, and feces and urine samples were collected. The samples were detected using ultrahigh-performance liquid chromatography-mass spectrometry. The data were analyzed using multivariate statistical analysis such as principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). Related differential metabolites were identified through database comparisons between two groups based on the MS and KEGG. Results: Compared to healthy children, the metabolites glucuronic acid, xanthine, and indole-3-acetaldehyde tend to be reduced in children with spleen-deficiency. Moreover, these children showed an increase in metabolites such as quinic acid, adenine, 4-methyl-5-thiazole-ethanol, 3-formyl indole, and 5-hydroxy indole-3-acetic acid. The condition affected many of the critical metabolic pathways, including the metabolism of tryptophan, cysteine, methionine, and pentose phosphate. Conclusion: The children with spleen-deficiency had disorders at the metabolic level, which might be due to factors such as diet, personal preferences, and genes, leading to various symptoms, making spleen-deficiency children more prone to suffer from digestive diseases than healthy children. The results set a basis for the research on children's TCM constitution, which can be a reference to further studies to deal with the spleen-deficiency.

7.
Sci Total Environ ; 875: 162601, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36882141

RESUMO

Accurate modeling of Gross Primary Productivity (GPP) in terrestrial ecosystems is a major challenge in quantifying the carbon cycle. Many light use efficiency (LUE) models have been developed, but the variables and algorithms used for environmental constraints in different models vary importantly. It is still unclear whether the models can be further improved by machine learning methods and the combination of different variables. Here, we have developed a series of RFR-LUE models, which used the random forest regression (RFR) algorithm based on variables of LUE models, to explore the potential of estimating site-level GPP. Based on remote sensing indices, eddy covariance and meteorological data, we applied RFR-LUE models to evaluate the effects of different variables combined on GPP on daily, 8-day, 16-day and monthly scales, respectively. Cross-validation analyses revealed performances of RFR-LUE models varied significantly among sites with R2 of 0.52-0.97. Slopes of the regression relationship between simulated and observed GPP ranged from 0.59 to 0.95. Most models performed better in capturing the temporal changes and magnitude of GPP in mixed forests and evergreen needle-leaf forests than in evergreen broadleaf forests and grasslands. Performances were improved at the longer temporal scale, with the average R2 for four-time resolutions of 0.81, 0.87, 0.88, and 0.90, respectively. Additionally, the importance of the variables showed that temperature and vegetation indices were critical variables for RFR-LUE models, followed by radiation and moisture variables. The importance of moisture variables was higher in non-forests than in forests. A comparison with four GPP products indicated that RFR-LUE model predicted GPP better matcher observed GPP across sites. The study provided an approach to deriving GPP fluxes and evaluating the extent to which variables affect GPP estimation. It may be used for predicting vegetation GPP at the regional scales and for calibration and evaluation of land surface process models.

8.
Nanotechnology ; 34(23)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36863007

RESUMO

Y-doping can effectively improve the performance of HfOx-based resistive random-access memory (RRAM) devices, but the underlying physical mechanism of Y-doping affecting the performance of HfOx-based memristors is still missing and unclear. Although impedance spectroscopy (IS) has been widely used to investigate impedance characteristics and switching mechanisms of RRAM devices, there is less IS analysis on Y-doped HfOx-based RRAM devices as well as devices at different temperatures. Here, the effect of Y-doping on the switching mechanism of HfOx-based RRAM devices with a Ti/HfOx/Pt structure were reported using current-voltage characteristics and IS. The results indicated that doping Y into HfOxfilms could decrease the forming/operate voltage and improve the RS uniform. Both doped and undoped HfOx-based RRAM devices obeyed the oxygen vacancies (VO) conductive filament model along the grain boundary (GB). Additionally, the GB resistive activation energy of the Y-doped device was inferior to that of the undoped device. It exhibited a shift of theVOtrap level towards the conduction band bottom after Y-doping in the HfOxfilm, which was the main reason for the improved RS performance.

9.
ACS Appl Mater Interfaces ; 15(14): 18537-18549, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36987379

RESUMO

We investigated the effect of nitrogen-hydrogen (NH) mixed plasma pretreatment of 4H-SiC surfaces on SiC surface properties, SiO2/SiC interface quality, and the reliability and voltage stability of metal-oxide-semiconductor (MOS) capacitors. The NH plasma pretreatment decreased the incomplete oxide and contaminants on the SiC surface and reduced the density of SiO2/SiC interface traps. Compared with the untreated sample, the dielectric insulating characteristics and reliability of samples pretreated by NH plasma were improved. We also demonstrated that the shift/hysteresis of the flat band voltage (Vfb) and the midgap voltage (Vmg) induced by bias temperature stress for SiC MOS capacitors after NH plasma pretreatment was significantly decreased. Furthermore, the mechanisms of NH plasma pretreatment to improve interface properties and device performances were determined by combining secondary ion mass spectrometry (SIMS) measurements, X-ray photoelectron spectroscopy (XPS), and first-principles calculations. The result indicates that the excessive oxidation at the SiO2/SiC interface was limited due to the reduction in the diffusion of oxygen atoms into SiC caused by the surface Si-H and Si-N; NH plasma pretreatment suppressed the generation of interfacial traps by reducing surface pollutants and passivating surface defects, and some N atoms introduced into the SiO2/SiC interface effectively passivated the interfacial electroactive traps.

10.
Curr Probl Cancer ; 47(3): 100956, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36966677

RESUMO

OBJECTIVE: Treatment-related toxicity following stereotactic ablative radiotherapy (SABR) in patients with central and ultracentral non-small cell lung cancer (NSCLC) is of potential concern, and the best regimens are still being explored. This study aimed to evaluate the clinical outcomes and toxicities of the patients with ultracentral and central NSCLC treated with SABR at our institution. METHOD: This retrospective study included patients with central and ultracentral NSCLC treated with SABR to prescription doses of 50 Gy in five fractions, 56 Gy in seven fractions, or 60 Gy in ten fractionsat Jiangsu Cancer Hospital between May 2013 and October 2018. The patients were grouped as central or ultracentral tumors.Overall survival (OS), progression-free survival (PFS), and grade ≥3 toxicities were analyzed. RESULTS: Forty patients (31 male, nine female) were included. Median follow-up was 41 (5-81) months. The 1-, 2-, and 3-year OS rates were 90.0%, 83.6%, and 66.0%, respectively, and the 1-, 2-, and 3-year PFS rates were 82.5%, 62.9%, and 54.2%, respectively. OS in the ultracentral group was inferior compared with the central group (median, 52.0 months, 95%CI: 43.0-61.0 vs. not reached, P=0.03).The median PFS was 38.0 months in the ultracentral group (95%CI: 19.8-56.2) vs. not reached in the central group, although this difference was not statistically significant (P= 0.06). The overall incidence of grade ≥3 toxicity was five (12.5%) patients, (5 in the ultracentralgroup vs. 0 in the central group; P=0. 11), including one patient with grade 3 pneumonitis, two with grade 3 bronchial obstruction, one with grade 5 bronchial obstruction, and one with grade 5 esophageal perforation. CONCLUSION: Worse outcomes were obseverd in patients with ultracentral NSCLC than those with central tumors after SABR. Higher rate of treatment-related grade 3 or more toxicity was observed in the ultracentral group.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radiocirurgia , Humanos , Masculino , Feminino , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Radiocirurgia/efeitos adversos , Estudos Retrospectivos , Incidência , Resultado do Tratamento
11.
Dalton Trans ; 51(47): 17938-17941, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36413053

RESUMO

Photogenerated carrier behavior at a CO2/Cs2AgBiBr6 quantum dot (QD) interface is investigated. In situ photovoltage spectra reveal electron transfer from the Cs2AgBiBr6 QDs to CO2. Moreover, this carrier transfer prefers Bi3+ sites (over Ca+ and Ag+ sites) due to them exhibiting the lowest adsorption energy (Eads = -0.125 eV) and CO2-Bi3+ interactions being more stable.

12.
Dalton Trans ; 51(45): 17292-17300, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36317601

RESUMO

Interface modification is an important means to enhance the photovoltaic performance of quantum dot sensitized solar cells (QDSCs). The TiO2/CdS/CdSe solar cells are sensitized with CdS QDs and CdSe QDs, which inevitably introduces a new interface to form a recombination center. Therefore, it is necessary to coat a passivation layer in order to effectively inhibit charge recombination at the CdS/CdSe interface. In this work, CuInS2 (CIS) has been introduced into the CdS/CdSe QD system as an inner passivation layer and the CdS/CIS/CdSe photoanode structure has been fabricated in an environmentally friendly manner. The extracted charge amount (Q) is used to express the charge separation efficiency, indicating that we have obtained outstanding charge extraction efficiency in CIS based CdS/CdSe QDSCs. As a result, the photocurrent density of the TiO2/CdS/CIS/CdSe photoanode significantly has increased from 19.01 mA cm-2 to 22.74 mA cm-2 (TiO2/CdS/CdSe photoanode), which demonstrates a higher photoconversion efficiency of 4.52% in comparison with that of TiO2/CdS/CdSe photoanode.

13.
Front Mol Biosci ; 9: 1035772, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438657

RESUMO

Renal fibrosis (RF) is the common pathological manifestation and central treatment target of multiple chronic kidney diseases with high morbidity and mortality. Currently, the molecular mechanisms underlying RF remain poorly understood, and exploration of RF-related hub targets and pathways is urgently needed. In this study, two classical RF rat models (adenine and UUO) were established and evaluated by HE, Masson and immunohistochemical staining. To clear molecular mechanisms of RF, differentially expressed genes (DEGs) were identified using RNA-Seq analysis, hub targets and pathways were screened by bioinformatics (functional enrichment analyses, PPI network, and co-expression analysis), the screening results were verified by qRT-PCR, and potential drugs of RF were predicted by network pharmacology and molecular docking. The results illustrated that renal structures were severely damaged and fibrotic in adenine- and UUO-induced models, as evidenced by collagen deposition, enhanced expressions of biomarkers (TGF-ß1 and α-SMA), reduction of E-cadherin biomarker, and severe renal function changes (significantly decreased UTP, CREA, Ccr, and ALB levels and increased UUN and BUN levels), etc. 1189 and 1253 RF-related DEGs were screened in the adenine and UUO models, respectively. Two key pathways (AGE-RAGE and NOD-like receptor) and their hub targets (Tgfb1, Col1a1, Nlrc4, Casp4, Trpm2, and Il18) were identified by PPI networks, co-expressed relationships, and qRT-PCR verification. Furthermore, various reported herbal ingredients (curcumin, resveratrol, honokiol, etc.) were considered as important drug candidates due to the strong binding affinity with these hub targets. Overall, this study mainly identified two key RF-related pathways (AGE-RAGE and NOD-like receptor), screened hub targets (Tgfb1, Col1a1, Nlrc4, Casp4, Trpm2, and Il18) that involved inflammation, ECM formation, myofibroblasts generation, and pyroptosis, etc., and provided referable drug candidates (curcumin, resveratrol, honokiol, etc.) in basic research and clinical treatment of RF.

14.
Sensors (Basel) ; 22(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36298432

RESUMO

The high demand for pressure devices with miniaturization and a wide bearing range has encouraged researchers to explore new high-performance sensors from different approaches. In this study, a sensitive element based on graphene in-plane compression properties for realizing pressure sensing is experimentally prepared using microelectromechanical systems (MEMS) fabrication technology; it consists of a 50 µm thick, 1400 µm wide square multilayer component membrane and a graphene monolayer with a meander pattern. The prepared sample is extensively characterized and analyzed by using various techniques, including atomic force microscopy, Raman spectroscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, COMSOL finite element method, and density functional theory. The sensing performance of the new pressure sensor based on the sensitive element are obtained by theoretical analysis for electromechanical measurements of the sensitive element before and after low-temperature annealing in atmosphere. Results demonstrate that atmospheric annealing at 300 °C enhances the pressure sensing sensitivity by 4 times compared to pristine graphene without annealing, which benefits from the desorption of hydroxyl groups on the graphene surface during annealing. The sensitivity is comparable and even better than that of previous sensors based on graphene in-plane properties. Our results provide new insights into realizing high-performance MEMS devices based on 2D sensitive materials.

15.
PLoS One ; 17(9): e0274748, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36149857

RESUMO

Self-sovereign identity authentication protocol is an active research topic in the field of identity authentication and management. However, the current SSI authentication protocols pay little attention to privacy protection and the fine-grained access control. Therefore, a secure and decentralized SSI authentication protocol with privacy protection and fine-grained access control is proposed. Firstly, the formal model of SSI including the SDPP-SSI identity model and management model is presented. And then, based on the federated blockchain, the distributed identifier is used as a global identifier for users in the decentralized domain. Finally, the verifiable statement is encapsulated using a policy control signature supporting privacy protection to develop the user's access control for identity registration in the centralized domain. Compared with the related work (Lin 2018, Zhu 2018, Stokkink 2018, Hammudoglu 2017, Othman 2017, Abraham 2018, Guan 2019, Lin 2019) from controllability, security, flexibility, privacy protection, authentication and fine-grained access control, the proposed SSI authentication protocol not only meets controllability, authentication, and flexibility, but also supports privacy protection and fine-grained access control.


Assuntos
Blockchain , Privacidade , Segurança Computacional , Confidencialidade
16.
Front Psychiatry ; 13: 930212, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35990083

RESUMO

Objective: To analyse differences in sex, age, depression, insomnia, psychological stress, resilience, and perceived social support among patients with medically unexplained symptoms (MUS) in a psychological clinic of a general hospital, and to explore the influencing factors of MUS. Methods: This is a cross-sectional study. Seven hundred forty-six first-time patients were assessed with the integrated psychosomatic comprehensive evaluation system (IPS) to evaluate their MUS, depression, insomnia, psychological stress, resilience, and perceived social support. The psychological characteristics were compared with regard to sex and age group (<25 years, low age group; 26-44 years, middle age group; >45 years, high age group). The relationships between age and MUS were explored, and how psychological stress affects MUS was analyzed using the mediator effect model. Results: Different age groups had significant differences in sex, MUS, depression, psychological stress, resilience, and perceived social support. In further pairwise comparison, no significant difference existed in depression, psychological stress, resilience and perceived social support in the middle and low age groups, depression and psychological stress were higher than those in the high age group, resilience and perceived social support were lower than those of the high age group. MUS were higher in the middle age group than in the low age group. No significant difference existed between the two groups and the high age group. Age, severity of MUS, and perceived social support were significantly different between the sexes. Differences in MUS between men and women in different age groups were analyzed using two-factor analysis of variance. It revealed no interaction between sex and different age groups on MUS. The main effect analysis showed that the effects of different age groups on MUS were statistically significant. Based on pairwise comparative analysis, the MUS score in the low age group was lower than that in the middle age group. To clarify a nonlinear relationship between age and MUS, threshold effect analysis was conducted. The results indicated that the piecewise linear regression model could better depict the relationship between age and MUS. The inflection point was at the age of 60 years. Before the age of 60 years, MUS increased with age. No significant correlation existed between age and MUS after the age of 60 years. To understand the influencing factors of MUS, the intermediary effect model was analyzed using MUS as the dependent variable, psychological stress as the independent variable, resilience as mediator variable M1, perceived social support as mediator variable M2, and depression as mediator variable M3. Resilience, perceived social support, and depression had significant mediator effects on the effects of psychological stress on MUS with a total indirect effect of 69.81%. Conclusion: The middle age group had greater MUS than the low age group. Before the age of 60 years, MUS increased with increasing age. Women had more severe MUS than men. Resilience, perceived social support, and depression had significant mediating effects on the effects of perceived stress on MUS. These findings suggest that clinicians should make more comprehensive and detailed evaluations and timely intervention for middle-aged and female patients. Improving psychological resilience and social support can reduce the impact of psychological stress on MUS. Therefore, psychotherapy and multidisciplinary comprehensive treatment are very important for patients is very important for patients.

18.
J Ethnopharmacol ; 292: 115213, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35331878

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Smilax glabra Roxb., the dry rhizome of Sarsaparilla, which is also known as Tu fuling (TFL) in China, is a well-known traditional CHINESE medicine that is widely used for detoxication, relieving dampness and as a diuretic. We have previously shown that the extracted TFL flavonoids (designated TFLF) possess anti-cardiac hypertrophy effects in vitro. However, the anti-cardiac hypertrophy effects of TFLF in vivo and the underlying mechanisms remain to be elucidated. AIM OF THE STUDY: To reveal the underlying therapeutic mechanism of TFLF on cardiac hypertrophy by using transverse aortic constriction (TAC) model and cellular assays in vitro. MATERIAL & METHODS: Cardiac hypertrophy was replicated by TAC surgery in rats or by isoprenaline treatment of rat H9C2 myocardial cells in vitro. Cardiac structure and function were evaluated by echocardiographic and hemodynamic examinations in vivo and histological analysis of tissues ex vivo. Biochemical kits and quantitative PCR were used to analyze markers of cardiac hypertrophy. Expression and phosphorylation of key proteins in the Raf/MEK/ERK pathway were quantified by Western blotting. We further confirmed our findings in H9C2 rat cardiomyocytes treated with isoprenaline and the ERK inhibitor in vitro. RESULTS: TFLF attenuated cardiac hypertrophy and fibrosis and improved cardiac dysfunction in TAC rats. TFLF treatment induced a strong reduction in serum NT-proBNP levels. Cardiac hypertrophy marker gene (ANP, BNP and ß-MHC) expression and the phosphorylation levels of c-Raf and ERK1/2 were decreased by TFLF treatment. TFLF also protected H9C2 cells from isoprenaline-induced hypertrophy in vitro via a similar molecular mechanism as that observed in the rat heart. Moreover, pretreatment with TRLF and the ERK inhibitor further inhibited the mRNA overexpression of hypertrophic genes in vitro. CONCLUSIONS: TFLFs may protect against pathological cardiac hypertrophy via negative regulation of the Raf/MEK/ERK pathway. Thus, TFLFs are implicated as a potential pharmacological agent for treating cardiac hypertrophy in clinical practice.


Assuntos
Smilax , Animais , Cardiomegalia/induzido quimicamente , Cardiomegalia/tratamento farmacológico , Cardiomegalia/prevenção & controle , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Isoproterenol/farmacologia , Sistema de Sinalização das MAP Quinases , Quinases de Proteína Quinase Ativadas por Mitógeno , Miócitos Cardíacos , Ratos , Smilax/química
19.
Am J Transl Res ; 14(1): 223-239, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35173840

RESUMO

OBJECTIVE: To investigate the function and mechanism of miR-1179 in the tumorigenesis of hepatocellular carcinoma (HCC). METHODS: The levels of miR-1179 and NUAK2 in clinical tissues or cell lines were examined using quantitative Real-time PCR (qRT-PCR). Cell Counting Kit-8 (CCK-8), EdU assay, colony formation, wound healing, Transwell assays and flow cytometry assays were conducted to examine the impact of miR-1179 on HCC cells. The protein expression of NUAK2 was detected using Western blotting assay. Bioinformatics analysis and luciferase reporter assays were conducted to reveal the association of miR-1179 with NUAK2. RESULTS: MiR-1179 expression was significantly downregulated in HCC specimens and cell lines compared to normal samples and cells. The miR-1179 overexpression inhibited HCC cell migration, invasion and proliferation through targeting NUAK2. Overexpression of NUAK2 can reverse the effect of miR-1179 on hepatocellular carcinoma cells. CONCLUSION: miR-1179 suppresses HCC developmen through targeting NUAK2. Which can be used as a potent HCC diagnostic marker.

20.
Clin Transl Oncol ; 24(7): 1413-1424, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35220552

RESUMO

PURPOSE: As an epigenetic regulation mechanism after transcription, RNA modification is installed by endogenous "writer" enzymes and is widely involved in a variety of physiological processes, including cancer progression. This study explored the RNA modification patterns of cervical cancer to clarify overall effect of RNA modification on tumor microenvironment (TME) characteristics and immune/targeted therapy. METHODS: 26 RNA modification "writers" were clustered, and the RNA modification patterns and TME characteristics of cervical cancer patients in TCGA were systematically evaluated. Based on differentially expressed genes (DEGs) between different RNA modification patterns, an RNA modification "writer" score (WM score) system was developed to assess the RNA modification of a single sample. RESULTS: Two different RNA modification patterns of cervical cancer were identified, and these patterns were significantly related to the prognosis and TME infiltration characteristics of patients. WM score was an independent risk factor for the prognosis of cervical cancer. High WM score was characterized by poor prognosis, low immune infiltration and low tumor mutation burden (TMB), while low-WM score was related to relatively long overall survival (OS), more immune components in TME and increased TMB. In addition, the low-WM score group was expected to be more sensitive to programmed cell death protein 1 (PD-1) therapy and showed lower predicted IC50 of chemotherapy drugs paclitaxel and cisplatin treatment. CONCLUSIONS: This study identified and characterized RNA modification patterns, and clarified potential relationship between RNA modification patterns and immune infiltration characteristics and immunotherapy of cervical cancer, offering a new evaluation scheme for treatment of cervical cancer patients.


Assuntos
Microambiente Tumoral , Neoplasias do Colo do Útero , Biomarcadores Tumorais/genética , Epigênese Genética , Feminino , Humanos , Prognóstico , RNA/genética , Microambiente Tumoral/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/terapia
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