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1.
Cogn Sci ; 48(4): e13440, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38606615

RESUMO

People implicitly generalize the actions of known individuals in a social group to unknown members. However, actions have social goals and evaluative valences, and the extent to which actions with different valences (helpful and harmful) are implicitly generalized among group members remains unclear. We used computer animations to simulate social group actions, where helping and hindering actions were represented by aiding and obstructing another's climb up a hill. Study 1 found that helpful actions are implicitly expected to be shared among members of the same group but not among members of different groups, but no such effect was found for harmful actions. This suggests that helpful actions are more likely than harmful actions to be implicitly generalized to group members. This finding was replicated in Study 2 by increasing the group size from three to five. Study 3 found that the null effect for generalizing harmful actions among group members is not due to the difficulty of detecting action generalization, as both helpful and harmful actions are similarly generalized within particular individuals. Moreover, Study 4 demonstrated that weakening social group information resulted in the absence of implicit generalization for helpful actions, suggesting the specificity of group membership. Study 5 revealed that the generalization of helping actions occurred when actions were performed by multiple group members rather than being repeated by one group member, showing group-based inductive generalization. Overall, these findings support valence-dependent implicit action generalization among group members. This implies that people may possess different knowledge regarding valenced actions on category-based generalization.


Assuntos
Generalização Psicológica , Dinâmica de Grupo , Humanos
2.
PLoS One ; 19(3): e0300049, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38466737

RESUMO

In order to assess the electromagnetic exposure safety of passengers under the civil communication system of the subway, the radio-frequency (RF) electromagnetic environment of subway carriage is established by using COMSOL Multiphysics software, it includes a 1-1/4 " leaky coaxial cable (LCX1) and a 1-5/8" leaky coaxial cable (LCX2), which are designed to be the exposure sources, and twelve passengers at different position. The electromagnetic environment model has been verified through field measurement. The exposure dose distribution of twelve passengers is compared and analyzed, when LCX1 and LCX2 works respectively. The simulated results show that, to compare with LCX2, the electromagnetic dose absorbed by the passengers is reduced by 9.19% and 22.50% at 2100 MHz and 2600 MHz respectively. The specific absorption rate (SAR) of passengers obtains the maximum value of 1.91×10-4 W/Kg and the temperature rise to 0.214 K when the LCX1 works at 3400 MHz. By comparing with the public exposure limitation of the International Commission of Non-Ionizing Radiation Protection (ICNIRP), it demonstrates the electromagnetic exposure safety of the passengers under the civil communication system. More importantly, the proposed LCX1 not only could add the 5G signal cover but also lower the SAR absorbed by the passengers, which indicates that the public electromagnetic exposure dose could be reduced by adjusting the radiation performances of exposure source, which provide a new way for electromagnetic protecting.


Assuntos
Campos Eletromagnéticos , Ferrovias , Campos Eletromagnéticos/efeitos adversos , Ondas de Rádio/efeitos adversos , Temperatura , Comunicação
3.
Inflammation ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315275

RESUMO

Atherosclerosis is initiated by vascular endothelial dysfunction, and low-shear stress (LSS) of blood flow is a key factor leading to endothelial dysfunction. Growing evidence suggests that endothelial cell pyroptosis plays an important role in the development of atherosclerosis. Studies have shown that low-shear stress can induce endothelial cell pyroptosis, but the exact mechanism remains unclear. Our experiments demonstrated that low-shear stress induced endothelial cell pyroptosis and the phosphorylation of IκB kinase ε (IKKε). IKKε knockdown not only significantly attenuated atherosclerosis lesions of aortic arch areas in ApoE-/- mice fed with high cholesterol diets, but also markedly reduced endothelial cell pyroptosis and NLRP3 expression triggered by low-shear stress. Further mechanism studies showed that IKKε promoted the expression of NLRP3 via activating signal transducer and activator of transcription 1 (STAT1) and the subsequent binding of STAT1 to NLRP3 promoter region. These results suggest that low-shear stress plays a pro-atherosclerotic role by promoting endothelial cell pyroptosis through the IKKε/STAT1/NLRP3 pathway, which provides new insights into the formation of atherosclerosis.

4.
Dig Surg ; 41(1): 42-52, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38295782

RESUMO

INTRODUCTION: This study aimed to evaluate associations between frailty and outcomes in patients with intrahepatic cholangiocarcinoma (ICC) undergoing hepatic lobectomy using a large, nationally representative sample. METHODS: This population-based, retrospective observational study extracted the data of adults ≥20 years old with ICC undergoing hepatic lobectomy from the US Nationwide Inpatient Sample database between 2005 and 2018. Frailty was assessed by the validated Hospital Frailty Risk Score (HFRS). Associations between frailty and surgical outcomes were analyzed using logistic regression analyses. RESULTS: After exclusions, 777 patients were enrolled, including 427 frail and 350 non-frail. Patients' mean age was 64.5 (±0.4) years and the majority were males (51.1%) and whites (76.5%). Frailty was significantly associated with increased odds of in-hospital mortality (aOR: 18.51, 95% CI: 6.70, 51.18), non-home discharge (aOR: 3.58, 95% CI: 2.26, 5.66), prolonged LOS (aOR: 5.56, 95% CI: 3.87, 7.99), perioperative cardiac arrest/stroke (aOR: 5.44, 95% CI: 1.62, 18.24), acute respiratory distress syndrome (ARDS)/respiratory failure (aOR: 3.88, 95% CI: 2.40, 6.28), tracheostomy/ventilation (aOR: 3.83, 95% CI: 2.23, 6.58), bleeding/transfusion (aOR: 1.67, 95% CI: 1.24, 2.26), acute kidney injury (AKI) (aOR: 14.37, 95% CI: 7.13, 28.99), postoperative shock (aOR: 4.44, 95% CI: 2.54, 7.74), and sepsis (aOR: 11.94, 95% CI: 6.90, 20.67). DISCUSSION/CONCLUSION: Among patients with ICC undergoing hepatic lobectomy, HFRS-defined frailty is a strong predictor of worse in-patient outcomes, including in-hospital death, prolonged LOS, unfavorable discharge, and complications (perioperative cardiac arrest/stroke, ARDS/respiratory failure, tracheostomy/ventilation, bleeding/transfusion, AKI, postoperative shock, and sepsis). Study results may help stratify risk in frail patients undergoing hepatic resection for ICC.


Assuntos
Injúria Renal Aguda , Colangiocarcinoma , Fragilidade , Parada Cardíaca , Síndrome do Desconforto Respiratório , Insuficiência Respiratória , Sepse , Acidente Vascular Cerebral , Adulto , Masculino , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Feminino , Pacientes Internados , Fragilidade/complicações , Fragilidade/epidemiologia , Mortalidade Hospitalar , Estudos Retrospectivos , Colangiocarcinoma/cirurgia , Fatores de Risco , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Tempo de Internação
5.
BMC Med ; 22(1): 29, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38267950

RESUMO

BACKGROUND: A previously trained deep learning-based smartphone app provides an artificial intelligence solution to help diagnose biliary atresia from sonographic gallbladder images, but it might be impractical to launch it in real clinical settings. This study aimed to redevelop a new model using original sonographic images and their derived smartphone photos and then test the new model's performance in assisting radiologists with different experiences to detect biliary atresia in real-world mimic settings. METHODS: A new model was first trained retrospectively using 3659 original sonographic gallbladder images and their derived 51,226 smartphone photos and tested on 11,410 external validation smartphone photos. Afterward, the new model was tested in 333 prospectively collected sonographic gallbladder videos from 207 infants by 14 inexperienced radiologists (9 juniors and 5 seniors) and 4 experienced pediatric radiologists in real-world mimic settings. Diagnostic performance was expressed as the area under the receiver operating characteristic curve (AUC). RESULTS: The new model outperformed the previously published model in diagnosing BA on the external validation set (AUC 0.924 vs 0.908, P = 0.004) with higher consistency (kappa value 0.708 vs 0.609). When tested in real-world mimic settings using 333 sonographic gallbladder videos, the new model performed comparable to experienced pediatric radiologists (average AUC 0.860 vs 0.876) and outperformed junior radiologists (average AUC 0.838 vs 0.773) and senior radiologists (average AUC 0.829 vs 0.749). Furthermore, the new model could aid both junior and senior radiologists to improve their diagnostic performances, with the average AUC increasing from 0.773 to 0.835 for junior radiologists and from 0.749 to 0.805 for senior radiologists. CONCLUSIONS: The interpretable app-based model showed robust and satisfactory performance in diagnosing biliary atresia, and it could aid radiologists with limited experiences to improve their diagnostic performances in real-world mimic settings.


Assuntos
Atresia Biliar , Aplicativos Móveis , Lactente , Criança , Humanos , Vesícula Biliar/diagnóstico por imagem , Inteligência Artificial , Atresia Biliar/diagnóstico por imagem , Estudos Retrospectivos , Radiologistas
6.
Macromol Rapid Commun ; 45(4): e2300585, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37931222

RESUMO

Flexible dielectrics with large dielectric constant (ε') coupled with low loss are highly pursued in many applications. To bolster the ε' of raw Zn (zinc)/poly(vinylidene fluoride, PVDF) while maintaining pimping dielectric loss, in this study, the core@double-shell structured Zn@zinc carbonate (ZnCH)@polystyrene (PS) particles are first synthesized through a suspension polymerization of styrene, and then composited with PVDF to elevate the ε' and keep low loss of the composites. By optimizing the PS shells' thickness and tailoring the electrical resistivity of Zn@ZnCH@PS particles, both the slow inter-particle polarization and fast intra-particle polarization in the composites can be decoupled and synergistically tuned, thus, the Zn@ZnCH@PS/PVDF achieves a much higher ε' and lower dielectric loss, simultaneously, which far exceed the unmodified Zn/PVDF. Both experiment and theoretic calculation reveal that the double-shell ZnCH@PS not only induces and promotes multiple polarizations enhancing the composites' ε', especially at the optimized PS's thickness, but also maintains suppressed loss and conductivity thanks to their obvious barrier effect on long-range charge migration. The core@double-shell filler design strategy facilitates the development of polymer composites with desirable dielectric properties for applications in electronic and electrical power systems.


Assuntos
Polímeros de Fluorcarboneto , Poliestirenos , Polivinil , Condutividade Elétrica , Zinco
7.
Ultrasound Q ; 39(4): 228-234, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37918027

RESUMO

ABSTRACT: The application of intracavity contrast-enhanced ultrasound in the evaluation of biliary disease has been confirmed valuable among pediatric population. This pictorial essay aims to demonstrate the role of percutaneous ultrasound cholangiography (PUSC) with microbubbles in the diagnosis of different pediatric biliary diseases in our center. The biliary system's morphologic characteristics in PUSC mode of neonatal hepatitis, biliary atresia, choledochal cysts, and biliary complications of hepatobiliary surgery are presented.


Assuntos
Atresia Biliar , Sistema Biliar , Recém-Nascido , Criança , Humanos , Lactente , Microbolhas , Colangiografia , Sistema Biliar/diagnóstico por imagem , Atresia Biliar/diagnóstico por imagem , Atresia Biliar/complicações , Ultrassonografia
8.
Chem Biol Drug Des ; 102(6): 1568-1577, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37735740

RESUMO

Baicalein, one of the active ingredients of banxia xiexin decoction, has good therapeutic efficacy in treating diarrhea and improving gastrointestinal dysfunction. The role and mechanism of Baicalein on irinotecan (CPT-11)-induced gastrointestinal dysfunction are the focus of this study. Concretely, CPT-11 induced delayed diarrhea rat model and intestinal epithelial cell (IEC)-6 cell injury model with Baicalein treatment as needed. Colonic pathological changes were analyzed by hematoxylin-eosin staining, and inflammatory factor expressions in serum were determined by enzyme-linked immunosorbent assay. Immunohistochemistry and western blot were performed to quantify ferroptosis-related protein expressions. Thiobarbituric acid reactive substances (TBARS) kits and colorimetric assay kit were applied to detect lipid peroxidation levels and Fe2+ content, respectively. In vitro experiments also included quantitative real-time polymerase chain reaction, cell counting kit-8, and C11 BODIPY staining. CPT-11 induced aggravation of intestinal tissue damage, inflammatory factor release, Fe2+ accumulation, upregulation of lipid peroxidation and 15-Lipoxygenase (ALOX15) expression, and downregulation of glutathione peroxidase 4 (Gpx4) and SLC7A11 in vivo in rats; however, Baicalein dose-dependently reversed the effects of CPT-11. Baicalein elevated cell viability, reduced lipid peroxidation and Fe2+ accumulation, and elevated Gpx4 and SLC7A11 levels, whereas ALOX15 overexpression reversed the effects of Baicalein on a CPT-11-induced IEC-6 cell injury model. In conclusion, Baicalein plays a mitigating role in CPT-11-induced delayed diarrhea via ALOX15-mediated ferroptosis.


Assuntos
Ferroptose , Ratos , Animais , Irinotecano , Araquidonato 15-Lipoxigenase/genética , Diarreia/tratamento farmacológico
9.
Small ; 19(52): e2303933, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37574266

RESUMO

Exploiting novel strategies for simultaneously harvesting ubiquitous, renewable, and easily accessible solar energy based on the photothermal effect, and efficiently storing the acquired thermal energy plays a vital role in revolutionizing the current fossil fuel-dominating energy structure. Developing black phosphorene-based phase-change composites with optimized photothermal conversion efficiencyand high latent heat is the most promising way to achieve efficient solar energy harvesting and rapid thermal energy storage. However, exfoliating high-quality black phosphorene nanosheets  remains challenging, Furthermore, an efficient strategy that can construct the aligned black phosphorene frameworks to maximize thermal conductivity enhancement is still lacking. Herein, high-quality black phosphorene nanosheets are prepared by an optimized exfoliating strategy. Meanwhile, by regulating the temperature gradient during freeze-casting, the framework consisting of shipshape aligned black phosphorene at long-range is successfully fabricated, improving the thermal conductivity of the poly(ethylene glycol) matrix up to 1.81 W m-1  K-1 at 20 vol% black phosphorene loading. The framework also endows the composite with excellent phase-change material encapsulation capacity and  high latent heat of 103.91 J g-1 . It is envisioned that the work advances the paradigm of contrasting frameworks with nanosheets toward controllable structure thermal enhancement of the composites.

10.
Hepatol Res ; 53(11): 1126-1133, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37519259

RESUMO

AIMS: Infants with biliary atresia (BA) are treated with Kasai portoenterostomy (KPE) surgery, but many BA patients need subsequent salvage liver transplants. The aim of this study is to develop a comprehensive gene-clinical model based on two-dimensional shear wave elastography (2DSWE), liver gene expression, and other clinical parameters to predict response to KPE for BA patients. METHODS: Differentially expressed gene patterns between liver samples of BA (n = 102) and non-BA control (n = 14) were identified using RNA sequencing analysis. Biliary atresia patients were then randomly assigned to training and validation cohorts. Gene classifier based on the differentially expressed genes was built in the training cohort. Nomogram models with and without gene classifier were further constructed and validated for predicting native liver survival of BA patients. The utility of the nomograms was compared by C-index. RESULTS: Using the least absolute shrinkage and selection operator model, we generated a nine-gene prognostic classifier. The nomogram based on the nine-gene classifier, age, preoperative 2DSWE, and albumin had the better C-index compared to gene classifier alone in the training cohort (0.83 [0.76-0.90] vs. 0.69 [0.61-0.77], p = 0.003) and the validation cohort (0.74 [0.67-0.82] vs. 0.62 [0.55-0.70], p = 0.001). Using risk scores developed from the nomogram, the 12-month survival rates of BA patients with native liver were 35.7% (95% confidence interval [CI], 22.7-56.3) in the high-risk group and 80.8% (95% CI, 63.4-100.0) in the low-risk group in the validation cohort. CONCLUSIONS: The comprehensive genetic-clinical nomogram based on preoperative 2DSWE, liver gene expression, and other clinical parameters can accurately predict response to KPE.

11.
JACC Heart Fail ; 11(8 Pt 2): 1135-1146, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37354146

RESUMO

BACKGROUND: Long-term benefits of pulmonary artery denervation (PADN) for patients with combined precapillary and postcapillary pulmonary hypertension (CpcPH) secondary to left heart failure are unknown. OBJECTIVES: The authors sought to report the 3-year clinical results of PADN for patients with CpcPH. METHODS: A total of 98 patients with CpcPH, defined as having mean pulmonary arterial pressure of ≥25 mm Hg, pulmonary capillary wedge pressure of >15 mm Hg, and pulmonary vascular resistance of >3.0 WU, were randomly assigned to receive the sham + sildenafil or PADN. The primary endpoint was the occurrence of clinical worsening defined as cardiopulmonary death, rehospitalization or heart/lung transplantation at 3-year follow-up. Changes in the 6-minute walk distance and N-terminal pro-B-type natriuretic peptide served as secondary points. RESULTS: At the 3-year follow-up, clinical worsening was reported in 49 (50.0%) patients, with 31 (62.0%) in the sham + sildenafil group and 18 (37.5%) in the PADN group (HR: 2.13 [95% CI: 1.19-3.81]; P = 0.011), largely driven by a higher rate of rehospitalization in the sham + sildenafil group (56.2% vs 35.4%; HR: 1.96 [95% CI: 1.07-3.58]; P = 0.029) by Cox proportional hazards regression. At the end of the study, cardiopulmonary-related deaths occurred in 16 (32.0%) patients in the sham and 9 (18.8%) (P = 0.167) patients in the PADN group. PADN also resulted in a more profound increase in the 6-minute walk distance and reduction in N-terminal pro-B-type natriuretic peptide. CONCLUSIONS: PADN is associated with significant improvements in exercise capacity, cardiac function, and clinical outcomes. Further study without approved drugs for pulmonary arterial hypertension is required to confirm the benefits of PADN for patients with CpcPH. (Pulmonary Arterial Denervation in Patients With Pulmonary Hypertension Associated With the Left Heart Failure [PADN-5]; NCT02220335).


Assuntos
Insuficiência Cardíaca , Hipertensão Pulmonar , Humanos , Hipertensão Pulmonar/etiologia , Artéria Pulmonar , Peptídeo Natriurético Encefálico , Citrato de Sildenafila/uso terapêutico , Insuficiência Cardíaca/complicações
12.
Pediatr Radiol ; 53(10): 2004-2012, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37294442

RESUMO

BACKGROUND: The pediatric liver contrast-enhanced ultrasound (CEUS) criteria were developed to improve the diagnostic performance of CEUS in differentiating pediatric benign and malignant liver lesions. However, the diagnostic performance of CEUS in the evaluation of multiple focal liver lesions in the pediatric population has not yet been fully evaluated. OBJECTIVE: To evaluate the diagnostic performance of the pediatric liver CEUS criteria in differentiating benign and malignant multifocal liver lesions in children. MATERIALS AND METHODS: From April 2017 to September 2022, the CEUS characteristics of multifocal liver lesions in patients < 18 years were analyzed. Lesions classified as CEUS-1, CEUS-2 or CEUS-3 were considered benign and lesions classified as CEUS-4 or CEUS-5 were considered malignant. The diagnostic performance of the pediatric liver CEUS criteria (i.e. sensitivity, specificity, positive predictive value [PPV], negative predictive value [NPV] and accuracy) was assessed. RESULTS: After exclusion, 21 patients (median age, 36.0 months; range, 1.0-204 months; 7 boys) were included. There were significant differences in the serum alpha fetoprotein level (P= 0.039) and the presence of washout (P < 0.001) between children with malignant and benign lesions. The sensitivity, specificity, PPV, NPV and accuracy of the pediatric liver CEUS criteria were 100.0% (10/10), 90.9% (10/11), 90.9% (10/11), 100.0% (10/10) and 95.2% (20/21), respectively. CONCLUSION: The pediatric liver CEUS criteria had excellent diagnostic performance in differentiating benign and malignant multifocal liver lesions in children.


Assuntos
Meios de Contraste , Neoplasias Hepáticas , Masculino , Humanos , Criança , Pré-Escolar , Sensibilidade e Especificidade , Ultrassonografia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Estudos Retrospectivos
13.
J Cell Biochem ; 124(3): 421-433, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36780445

RESUMO

As one of the common and serious chronic complications of diabetes mellitus (DM), the related mechanism of diabetic retinopathy (DR) has not been fully understood. Müller cell reactive gliosis is one of the early pathophysiological features of DR. Therefore, exploring the manner to reduce diabetes-induced Müller cell damage is essential to delay DR. Thioredoxin 1 (Trx1), one of the ubiquitous redox enzymes, plays a vital role in redox homeostasis via protein-protein interactions, including apoptosis signal-regulating kinase 1 (ASK1). Previous studies have shown that upregulation of Trx by some drugs can attenuate endoplasmic reticulum stress (ERS) in DR, but the related mechanism was unclear. In this study, we used DM mouse and high glucose (HG)-cultured human Müller cells as models to clarify the effect of Trx1 on ERS and the underlying mechanism. The data showed that the diabetes-induced Müller cell damage was increased significantly. Moreover, the expression of ERS and reactive gliosis was also upregulated in diabetes in vivo and in vitro. However, it was reversed after Trx1 overexpression. Besides, ERS-related protein expression, reactive gliosis, and apoptosis were decreased after transfection with ASK1 small-interfering RNA in stable Trx1 overexpression Müller cells after HG treatment. Taken together, Trx1 could protect Müller cells from diabetes-induced damage, and the underlying mechanism was related to inhibited ERS via ASK1.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Camundongos , Humanos , Animais , Células Ependimogliais/metabolismo , Gliose , Tiorredoxinas/genética , Tiorredoxinas/metabolismo , MAP Quinase Quinase Quinase 5/genética , MAP Quinase Quinase Quinase 5/farmacologia , Retinopatia Diabética/genética , Apoptose , Inflamação , Estresse do Retículo Endoplasmático
14.
J Affect Disord ; 329: 251-256, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36828145

RESUMO

During the Omicron pandemic, students in Shenzhen took classes at home via the internet, which could lead to internet addiction (IA) symptoms, and anxiety is often considered an important risk factor for IA. There are several different developmental stages within adolescence. However, no studies have explored the interaction between IA and anxiety at the symptom level using a longitudinal design stratified by age. A total of 2744 students completed the questionnaire 50 days after starting the online classes (T1) and 50 days after they returned to school (T2). A cross-lagged panel network model was used to describe the structure of the comorbidity network. With the help of bootstrapping, the Mann-Whitney U test was used to examine the differences between primary school students' and middle school students' networks. The results found that there is a bidirectional interaction between IA and anxiety, and anxiety plays a dominant role. Feeling afraid is the bridge symptom between IA and anxiety. IA did not show developmental stage differences, but anxiety did. These findings extend the model of compensatory internet use and suggest that, when alleviating IA symptoms in adolescents, attention should be given to their possible comorbid anxiety symptoms, especially in middle school students.


Assuntos
Comportamento Aditivo , Transtorno de Adição à Internet , Adolescente , Humanos , Transtorno de Adição à Internet/epidemiologia , Comportamento Aditivo/epidemiologia , Ansiedade/epidemiologia , Transtornos de Ansiedade , Estudantes , Internet
15.
Int Immunopharmacol ; 116: 109842, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36764279

RESUMO

Atherosclerosis is a focal chronic inflammatory disease, the initial pathogenic event of which is endothelial dysfunction, and disturbed flow (DF) is the primary and vital factor underlying endothelial dysfunction. The present research aims to elucidate the mechanism underlying the regulation of Neuropilin (NRP)2 under DF in endothelial cells (ECs) in an inflammatory state. We observed that NRP2 expression was significantly upregulated in DF-stimulated human umbilical vein endothelial cells (HUVECs). Knockdown of NRP2 in HUVECs significantly ameliorated cell inflammation induced by DF. In addition, quercetin inhibited NRP2 expression as well as endothelial inflammation. Animal experiments suggested that NRP2 knockdown or intraperitoneal injection of quercetin affected the expression of inflammation-related genes. Moreover, the upstream transcription factor GATA2 was found to regulate NRP2 transcription by binding to the -1100 to +100 bp region of the NRP2 promoter. Further studies showed that quercetin inhibited NRP2-VEGFC complex formation induced by disturbed flow, although did not inhibit GATA2 expression. These findings suggest that NRP2 plays an important role in promoting inflammation. Quercetin antagonizes atherosclerosis by inhibiting NRP2 and the formation of NRP2-VEGFC complex by inhibiting the inflammatory effects induced by disordered flow.


Assuntos
Aterosclerose , Quercetina , Animais , Humanos , Quercetina/farmacologia , Quercetina/uso terapêutico , Células Endoteliais da Veia Umbilical Humana/metabolismo , Aterosclerose/metabolismo , Inflamação/metabolismo
16.
Nanomaterials (Basel) ; 13(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36616120

RESUMO

An insulating shell on the surface of conductive particles is vital for restraining the dielectric loss and leakage current of polymer composites. So as to inhibit the enormous loss and conductivity of pristine nickel (Ni)/poly(vinylidene fluoride)(PVDF) composites but still harvest a high dielectric permittivity (εr) when filler loading approaches or exceeds the percolation threshold (fc), pristine Ni particles were covered by a layer of titanium dioxide (TiO2) shell via a sol-gel approach, and then they were composited with PVDF. The impacts of the TiO2 coating on the dielectric performances of the Ni/PVDF composites were explored as a function of the filler concentration, the shell thickness and frequency. In addition, the dielectric performances were fitted using the Havriliak-Negami (H-N) equation in order to further understand the TiO2 shell's effect on polarization mechanism in the composites. The Ni@TiO2/PVDF composites exhibit high εr and enhanced breakdown strength (Eb) but remarkably suppressed loss and conductivity when compared with pristine Ni/PVDF because the TiO2 shell can efficiently stop the direct contact between Ni particles thereby suppressing the long-range electron transportation. Further, the dielectric performances can be effectively tuned through finely adjusting the TiO2 shell' thickness. The resulting Ni@TiO2/PVDF composites with high εr and Eb but low loss show appealing applications in microelectronics and electrical fields.

17.
Adv Mater ; 35(2): e2207829, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36349800

RESUMO

Flexible dielectric and electronic materials with high dielectric constant (k) and low loss are constantly pursued. Encapsulation of conductive fillers with insulating shells represents a promising approach, and has attracted substantial research efforts. However, progress is greatly impeded due to the lack of a fundamental understanding of the polarization mechanism. In this work, a series of core-shell polymer composites is studied, and the correlation between macroscopic dielectric properties (across entire composites) and microscopic polarization (around single fillers) is investigated. It is revealed that the polarization in polymer conductor composites is determined by electron transport across multiple neighboring conductive fillers-a domain-type polarization. The formation of a core-shell filler structure affects the dielectric properties of tpolymer composites by essentially modifying the filler-cluster size. Based on this understanding, a novel percolative composite is prepared with higher-than-normal filler concentration and optimized shell's electrical resistivity. The developed composite shows both high-k due to enlarged cluster size and low loss due to restrained charge transport simultaneously, which cannot be achieved in traditional percolative composites or via simple core-shell filler design. The revealed polarization mechanism and the optimization strategy for core-shell fillers provide critical guidance and a new paradigm, for developing advanced polymer dielectrics with promising property sets.

18.
Biochem Biophys Res Commun ; 636(Pt 2): 62-70, 2022 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-36356543

RESUMO

Epicardial adipose tissue (EAT) is a metabolically active organ which generates inflammatory cytokines. Thickness of EAT is associated with onset and development of heart failure with preserved ejection fraction (HFpEF). However, it is still unclear the specific mechanisms and pharmacological targets on EAT induced inflammation in HFpEF. A two-hit protocol with western diet and Nω-nitrol-arginine methyl ester (L-NAME) was used to establish HFpEF mouse model. In HFpEF mice, inflammatory biomarkers, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1ß and von willebrand factor (vWF) elevated in myocardium compared to control. Inflammatory cell infiltration in myocardium was increased. In HFpEF mice, inflammasome-mediated pyroptosis pathway was activated in the EAT. Suppression of pyroptosis-related protein gasdermin D (GSDMD) in cultured EAT could lower cardiomyocyte inflammation and autophagy. Furthermore, spironolactone and rosuvastatin, the two-hit anti-inflammatory agents, reduced NLR family pyrin domain containing 3 (NLRP3)/GSDMD pyroptosis in EAT and autophagy in myocardium of HFpEF mouse. The combination treatment also enhanced exercise tolerance and appeased inflammatory injuries in HFpEF mice. CONCLUSION: Pyroptosis signaling is involved in EAT-myocardium axis in mouse model of HFpEF. Targeting adipocyte-derived inflammation in EAT bears potential to treatment HFpEF.


Assuntos
Insuficiência Cardíaca , Piroptose , Camundongos , Animais , Insuficiência Cardíaca/metabolismo , Volume Sistólico , Inflamassomos/metabolismo , Miocárdio/metabolismo , Tecido Adiposo/metabolismo , Inflamação/patologia , Modelos Animais de Doenças , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
19.
Front Cell Dev Biol ; 10: 963866, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438564

RESUMO

Background: Endothelial injury induced by low shear stress (LSS) is an initiating factor in the pathogenesis of various cardiovascular diseases, including atherosclerosis, hypertension, and thrombotic diseases. Low shear stress activates the mammalian target of rapamycin complex 2 (mTORC2) signaling pathway. Rictor, the main constituent protein of mTORC2, is involved in vascular development. However, the impact of conditional Rictor ablation on endothelial homeostasis, especially on endothelial-specific markers, such as vascular endothelial-cadherin (VE-cadherin) and von Willebrand factor (VWF), under blood flow stimulation is unclear. Objective: We aimed to investigate whether endothelial Rictor is involved in maintaining vascular endothelial integrity and the potential role of Rictor in atheroprone blood flow-mediated endothelial injury. Methods and results: Immunofluorescence staining showed that endothelial Rictor was successfully knocked out in a mouse model. Scanning electron microscopy (EM) detection revealed disruption of the endothelial monolayer in the thoracic aorta of Rictor-deficient mice. Furthermore, scanning electron microscopy and transmission electron microscopy showed that Rictor deletion disrupted endothelial integrity and expanded cell junctions in the left common carotid artery region. In vitro, low shear stress disrupted actin filament polarity and the promoted the translocation of vascular endothelial-cadherin, the key component of adherens junctions (AJs) in human umbilical vein endothelial cells. After Rictor downregulation by small interfering RNA, the translocation of vascular endothelial-cadherin and stress fibers increased. Rictor knockdown inhibited low shear stress-induced von Willebrand factor upregulation, and downregulation of vascular endothelial-cadherin decreased low shear stress-induced von Willebrand factor expression. These results suggest that vascular endothelial-cadherin/von Willebrand factor is a possible mechanism mediated by Rictor in the pathological process of low shear stress-induced endothelial injury. Conclusion: Rictor is a key protein that regulates endothelial integrity under vascular physiological homeostasis, and Rictor mediates low shear stress-induced endothelial injury by regulating adherens junctions and von Willebrand factor.

20.
Oxid Med Cell Longev ; 2022: 5842677, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36329801

RESUMO

The local heterogeneity in the distribution of atherosclerotic lesions is caused by local flow patterns. The integrin family plays crucial regulatory roles in diverse biological processes, but knowledge of integrin ß4 (ITGB4) in shear stress-induced atherosclerosis is limited. This study clarified that low shear stress (LSS) regulates the generation of ITGB4 in endothelial cells with atheroprone phenotype to identify ITGB4's role in atherosclerosis. We found that LSS led to an increase in ITGB4 protein expression both in vitro and in vivo. ITGB4 knockdown attenuated inflammation and ROS generation in human umbilical vein endothelial cells (HUVECs) and reduced atherosclerotic lesion areas in ApoE-/- mice fed with HFD, largely independent of effects on the lipid profile. Mechanistically, ITGB4 knockdown altered the phosphorylation levels of SRC, FAK, and NFκB in HUVECs under LSS conditions. In addition, the knockdown of NFκB inhibited the production of ITGB4 and SRC phosphorylation, and the knockdown of SRC downregulated ITGB4 protein expression and NFκB activation. These data demonstrate a critical role of ITGB4 in atherosclerosis via modulation of endothelial cell inflammation, and ITGB4/SRC/NFκB might form a positive feedback loop in the regulation of endothelial cell inflammation.


Assuntos
Aterosclerose , Integrina beta4 , Camundongos , Humanos , Animais , Integrina beta4/genética , Integrina beta4/metabolismo , Aterosclerose/patologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Estresse Mecânico , Inflamação/patologia , NF-kappa B/metabolismo
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