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1.
Adv Mater ; : e2401838, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748700

RESUMO

The advent of 2D ferroelectrics, characterized by their spontaneous polarization states in layer-by-layer domains without the limitation of a finite size effect, brings enormous promise for applications in integrated optoelectronic devices. Comparing with semiconductor/insulator devices, ferroelectric devices show natural advantages such as non-volatility, low energy consumption and high response speed. Several 2D ferroelectric materials have been reported, however, the device implementation particularly for optoelectronic application remains largely hypothetical. Here, the linear electro-optic effect in 2D ferroelectrics is discovered and electrically tunable 2D ferroelectric metalens is demonstrated. The linear electric-field modulation of light is verified in 2D ferroelectric CuInP2S6. The in-plane phase retardation can be continuously tuned by a transverse DC electric field, yielding an effective electro-optic coefficient rc of 20.28 pm V-1. The CuInP2S6 crystal exhibits birefringence with the fast axis oriented along its (010) plane. The 2D ferroelectric Fresnel metalens shows efficacious focusing ability with an electrical modulation efficiency of the focusing exceeding 34%. The theoretical analysis uncovers the origin of the birefringence and unveil its ultralow light absorption across a wide wavelength range in this non-excitonic system. The van der Waals ferroelectrics enable room-temperature electrical modulation of light and offer the freedom of heterogeneous integration with silicon and another material system for highly compact and tunable photonics and metaoptics.

3.
J Immunol ; 212(7): 1232-1243, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38391297

RESUMO

Pharmacological inhibition of IDO1 exhibits great promise as a strategy in cancer therapy. However, the failure of phase III clinical trials has raised the pressing need to understand the underlying reasons for this outcome. To gain comprehensive insights into the reasons behind the clinical failure of IDO1 inhibitors, it is essential to investigate the entire tumor microenvironment rather than focusing solely on individual cells or relying on knockout techniques. In this study, we conducted single-cell RNA sequencing to determine the overall response to apo-IDO1 inhibitor administration. Interestingly, although apo-IDO1 inhibitors were found to significantly activate intratumoral immune cells (mouse colon cancer cell CT26 transplanted in BALB/C mice), such as T cells, macrophages, and NK cells, they also stimulated the infiltration of M2 macrophages. Moreover, these inhibitors prompted monocytes and macrophages to secrete elevated levels of IL-6, which in turn activated the JAK2/STAT3 signaling pathway in tumor cells. Consequently, this activation enables tumor cells to survive even in the face of heightened immune activity. These findings underscore the unforeseen adverse effects of apo-IDO1 inhibitors on tumor cells and highlight the potential of combining IL-6/JAK2/STAT3 inhibitors with apo-IDO1 inhibitors to improve their clinical efficacy.


Assuntos
Inibidores Enzimáticos , Indolamina-Pirrol 2,3,-Dioxigenase , Interleucina-6 , Neoplasias , Animais , Camundongos , Inibidores Enzimáticos/farmacologia , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Camundongos Endogâmicos BALB C , Neoplasias/tratamento farmacológico , Linfócitos T/metabolismo , Microambiente Tumoral
4.
Chemosphere ; 350: 141186, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38215833

RESUMO

Increased use of bioplastics, such as polylactic acid (PLA), helps in reducing greenhouse gas emissions, decreases energy consumption and lowers pollution, but its degradation efficiency has much room for improvement. The degradation rate of electrospun PLA fibers of varying diameters ranging from 0.15 to 1.33 µm is measured during hydrolytic degradation under different pH from 5.5 to 10, and during aerobic biodegradation in seawater supplemented with activated sewage sludge. In hydrolytic conditions, varying PLA fiber diameter had significant influence over percentage weight loss (W%L), where faster degradation was achieved for PLA fibers with smaller diameter. W%L was greatest for PLA-5 > PLA-12 > PLA-16 > PLA-20, with average W%L at 30.7%, 27.8%, 17.2% and 14.3% respectively. While different pH environment does not have a significant influence on PLA degradation, with W%L only slightly higher for basic environments. Similarly biodegradation displayed faster degradation for small diameter fibers with PLA-5 attaining the highest degree of biodegradation at 22.8% after 90 days. Hydrolytic degradation resulted in no significant structural change, while biodegradation resulted in significant hydroxyl end capping products on the PLA surface. Scanning electron microscopy (SEM) imaging of degraded PLA fibers showed a deteriorated morphology of PLA-5 and PLA-12 fibers with increased adhesion structures and irregularly shaped fibers, while a largely unmodified morphology for PLA-16 and PLA-20.


Assuntos
Poliésteres , Poliésteres/química , Hidrólise , Microscopia Eletrônica de Varredura
5.
Sci Rep ; 13(1): 21597, 2023 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-38062236

RESUMO

Breast ultrasound segmentation remains challenging because of the blurred boundaries, irregular shapes, and the presence of shadowing and speckle noise. The majority of approaches stack convolutional layers to extract advanced semantic information, which makes it difficult to handle multiscale issues. To address those issues, we propose a three-path U-structure network (TPUNet) that consists of a three-path encoder and an attention-based feature fusion block (AFF Block). Specifically, instead of simply stacking convolutional layers, we design a three-path encoder to capture multiscale features through three independent encoding paths. Additionally, we design an attention-based feature fusion block to weight and fuse feature maps in spatial and channel dimensions. The AFF Block encourages different paths to compete with each other in order to synthesize more salient feature maps. We also investigate a hybrid loss function for reducing false negative regions and refining the boundary segmentation, as well as the deep supervision to guide different paths to capture the effective features under the corresponding receptive field sizes. According to experimental findings, our proposed TPUNet achieves more excellent results in terms of quantitative analysis and visual quality than other rival approaches.


Assuntos
Neoplasias da Mama , Neoplasias Mamárias Animais , Animais , Feminino , Humanos , Semântica , Ultrassonografia Mamária , Neoplasias da Mama/diagnóstico por imagem , Processamento de Imagem Assistida por Computador
6.
Entropy (Basel) ; 25(11)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37998243

RESUMO

Data sharing and analyzing among different devices in mobile edge computing is valuable for social innovation and development. The limitation to the achievement of this goal is the data privacy risk. Therefore, existing studies mainly focus on enhancing the data privacy-protection capability. On the one hand, direct data leakage is avoided through federated learning by converting raw data into model parameters for transmission. On the other hand, the security of federated learning is further strengthened by privacy-protection techniques to defend against inference attack. However, privacy-protection techniques may reduce the training accuracy of the data while improving the security. Particularly, trading off data security and accuracy is a major challenge in dynamic mobile edge computing scenarios. To address this issue, we propose a federated-learning-based privacy-protection scheme, FLPP. Then, we build a layered adaptive differential privacy model to dynamically adjust the privacy-protection level in different situations. Finally, we design a differential evolutionary algorithm to derive the most suitable privacy-protection policy for achieving the optimal overall performance. The simulation results show that FLPP has an advantage of 8∼34% in overall performance. This demonstrates that our scheme can enable data to be shared securely and accurately.

7.
Plants (Basel) ; 12(18)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37765423

RESUMO

Alnus cremastogyne is a rapidly growing broad-leaved tree species that is widely distributed in southwest China. It has a significant economic and ecological value. However, with the expansion of the planting area, the influence of phenotypic variation and differentiation on Alnus cremastogyne has increased, resulting in a continuous decline in its genetic quality. Therefore, it is crucial to investigate the phenotypic variation of Alnus cremastogyne and select excellent breeding materials for genetic improvement. Herein, four growth-related phenotypic traits (diameter at breast height, the height of trees, volume, height under the branches) and twelve reproductive-related phenotypic traits (fresh weight of single cone, dry weight of single cone, seed weight per plant, thousand kernel weight, cone length, cone width, cone length × cone width, fruit shape index, seed rate, germination rate, germination potential, germination index) of 40 clones from four provenances were measured and analyzed. The phenotypic variation was comprehensively evaluated by correlation analysis, principal component analysis and cluster analysis, and excellent clones were selected as breeding materials. The results revealed that there were abundant phenotypic traits variations among and within provenances. Most of the phenotypic traits were highly significant differences (p < 0.01) among provenances. The phenotypic variation among provenances (26.36%) was greater than that of within provenances clones (24.80%). The average phenotypic differentiation coefficient was accounted for 52.61% among provenances, indicating that the phenotypic variation mainly came from among provenances. The coefficient of variation ranged from 9.41% (fruit shape index) to 97.19% (seed weight per plant), and the repeatability ranged from 0.36 (volume) to 0.77 (cone width). Correlation analysis revealed a significantly positive correlation among most phenotypic traits. In principal component analysis, the cumulative contribution rate of the first three principal components was 79.18%, representing the main information on the measured phenotypic traits. The cluster analysis revealed four groups for the 40 clones. Group I and group II exhibited better performance phenotypic traits as compared with group III and group IV. In addition, the four groups are not clearly clustered following the distance from the provenance. Employing the multi-trait comprehensive evaluation method, 12 excellent clones were selected, and the average genetic gain for each phenotypic trait ranged from 4.78% (diameter at breast height) to 32.05% (dry weight of single cone). These selected excellent clones can serve as candidate materials for the improvement and transformation of Alnus cremastogyne seed orchards. In addition, this study can also provide a theoretical foundation for the genetic improvement, breeding, and clone selection of Alnus cremastogyne.

8.
Otolaryngol Head Neck Surg ; 169(6): 1582-1589, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37555251

RESUMO

OBJECTIVE: Validation of automated 2-dimensional (2D) diameter measurements of vestibular schwannomas on magnetic resonance imaging (MRI). STUDY DESIGN: Retrospective validation study using 2 data sets containing MRIs of vestibular schwannoma patients. SETTING: University Hospital in The Netherlands. METHODS: Two data sets were used, 1 containing 1 scan per patient (n = 134) and the other containing at least 3 consecutive MRIs of 51 patients, all with contrast-enhanced T1 or high-resolution T2 sequences. 2D measurements of the maximal extrameatal diameters in the axial plane were automatically derived from a 3D-convolutional neural network compared to manual measurements by 2 human observers. Intra- and interobserver variabilities were calculated using the intraclass correlation coefficient (ICC), agreement on tumor progression using Cohen's kappa. RESULTS: The human intra- and interobserver variability showed a high correlation (ICC: 0.98-0.99) and limits of agreement of 1.7 to 2.1 mm. Comparing the automated to human measurements resulted in ICC of 0.98 (95% confidence interval [CI]: 0.974; 0.987) and 0.97 (95% CI: 0.968; 0.984), with limits of agreement of 2.2 and 2.1 mm for diameters parallel and perpendicular to the posterior side of the temporal bone, respectively. There was satisfactory agreement on tumor progression between automated measurements and human observers (Cohen's κ = 0.77), better than the agreement between the human observers (Cohen's κ = 0.74). CONCLUSION: Automated 2D diameter measurements and growth detection of vestibular schwannomas are at least as accurate as human 2D measurements. In clinical practice, measurements of the maximal extrameatal tumor (2D) diameters of vestibular schwannomas provide important complementary information to total tumor volume (3D) measurements. Combining both in an automated measurement algorithm facilitates clinical adoption.


Assuntos
Neuroma Acústico , Humanos , Neuroma Acústico/diagnóstico por imagem , Neuroma Acústico/patologia , Inteligência Artificial , Estudos Retrospectivos , Algoritmos , Imageamento por Ressonância Magnética/métodos , Reprodutibilidade dos Testes
9.
Cancer Biol Ther ; 24(1): 2223375, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-37337460

RESUMO

Molecular mechanisms behind potentially inferior prognosis of old cholangiocarcinoma (CCA) patients are unclear. Prevalence of interventional targets and the difference between young and old CCA patients are valuable for promising precision medicine. A total of 188 CCA patients with baseline tumor tissue samples were subgrouped into the young (≤45 years) and old (>45 years) sub-cohorts. Somatic and germline mutation profiles, differentially enriched genetic alterations, and actionable genetic alterations were compared. An external dataset was used for the validation of molecular features and the comparison of overall survival (OS). Compared to young patients, KRAS alterations were more common in old patients (P = .04), while FGFR2 fusions were less frequent (P = .05). TERT promoter mutations were exclusively detected in old patients. The external dataset (N = 392) revealed no significant difference in OS between young and old patients; however, old patient-enriched KRAS (hazard ratio [HR]: 1.96, 95% confidence interval [CI]: 1.37-2.80) and TERT alterations (HR: 2.03, 95% CI: 1.22-3.38) were associated with inferior OS. Approximately 38.3% of patients were identified of actionable oncogenic mutations indicative of a potential response to targeted therapy or immunotherapy. Actionable FGFR2 fusions (P = .01) and BRAFV600E (P = .04) mutations were more frequent in young females than old patients. The enrichment of KRAS/TERT alterations in CCA patients over 45 years resulted in inferior OS. Approximately one-third of CCA patients were eligible for targeted therapy or immunotherapy given the actionable mutations carried, especially young females.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Feminino , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Colangiocarcinoma/genética , Colangiocarcinoma/terapia , Prognóstico , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/terapia , Genômica , Mutação
11.
Nat Commun ; 14(1): 1235, 2023 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-36871047

RESUMO

Fibroblast growth factor-18 (FGF18) has diverse organ development and damage repair roles. However, its role in cardiac homeostasis following hypertrophic stimulation remains unknown. Here we investigate the regulation and function of the FGF18 in pressure overload (PO)-induced pathological cardiac hypertrophy. FGF18 heterozygous (Fgf18+/-) and inducible cardiomyocyte-specific FGF18 knockout (Fgf18-CKO) male mice exposed to transverse aortic constriction (TAC) demonstrate exacerbated pathological cardiac hypertrophy with increased oxidative stress, cardiomyocyte death, fibrosis, and dysfunction. In contrast, cardiac-specific overexpression of FGF18 alleviates hypertrophy, decreased oxidative stress, attenuates cardiomyocyte apoptosis, and ameliorates fibrosis and cardiac function. Tyrosine-protein kinase FYN (FYN), the downstream factor of FGF18, was identified by bioinformatics analysis, LC-MS/MS and experiment validation. Mechanistic studies indicate that FGF18/FGFR3 promote FYN activity and expression and negatively regulate NADPH oxidase 4 (NOX4), thereby inhibiting reactive oxygen species (ROS) generation and alleviating pathological cardiac hypertrophy. This study uncovered the previously unknown cardioprotective effect of FGF18 mediated by the maintenance of redox homeostasis through the FYN/NOX4 signaling axis in male mice, suggesting a promising therapeutic target for the treatment of cardiac hypertrophy.


Assuntos
Fatores de Crescimento de Fibroblastos , Espectrometria de Massas em Tandem , Masculino , Animais , Camundongos , Cromatografia Líquida , Camundongos Knockout , Miócitos Cardíacos , Cardiomegalia
12.
Mol Biol Rep ; 50(4): 3469-3478, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36765018

RESUMO

BACKGROUND: Metformin, a first-line oral anti-diabetic drug, has recently been reported to exert protective effect on various cardiovascular diseases. However, the potential role of metformin in ethanol-induced cardiomyocyte injury is still unknown. Therefore, this study was aimed to investigate the effect of metformin on ethanol-induced cardiomyocyte injury and its underlying mechanism. METHODS AND RESULTS: H9c2 cardiomyocytes were exposed to ethanol for 24 h to establish an ethanol-induced cardiomyocyte injury model, and followed by treatment with metformin in the presence or absence of Lapatinib (an ErbB2 inhibition). CCK8 and LDH assays demonstrated that metformin improved cell viability in cardiomyocytes exposed to ethanol. Furthermore, metformin suppressed cardiomyocyte apoptosis and reduced the expressions of apoptosis-related proteins (Bax and C-CAS-3). In addition, our results showed that metformin activated the AKT/Nrf2 pathway, and then promoted Nrf2 nuclear translocation and the transcription of its downstream antioxidant genes (HO-1, CAT and SOD2), thereby inhibiting oxidative stress. Interestingly, we found that ErbB2 protein expression was significantly inhibited in ethanol-treated cardiomyocytes, which was markedly reversed by metformin. In contrast, Lapatinib largely abrogated the activation of AKT/Nrf2 signaling by metformin, accompanied by the increases in oxidative stress and cardiomyocyte apoptosis, indicating that metformin prevented ethanol-induced cardiomyocyte injury in an ErbB2-dependent manner. CONCLUSION: In summary, our study provides the first evidence that metformin protects cardiomyocyte against ethanol-induced oxidative stress and apoptosis by activating ErbB2-mediated AKT/Nrf2 signaling. Thus, metformin may be a potential novel treatment approach for alcoholic cardiomyopathy.


Assuntos
Metformina , Miócitos Cardíacos , Apoptose , Linhagem Celular , Etanol/farmacologia , Lapatinib/farmacologia , Metformina/farmacologia , Metformina/metabolismo , Miócitos Cardíacos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor ErbB-2/metabolismo
13.
Zhonghua Nan Ke Xue ; 29(10): 874-880, 2023 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-38639655

RESUMO

OBJECTIVE: To explor the potential mechanisms of ferroptosis involvement in non-obstructive azoospermia based on bioinformatics and machine learning methods. METHODS: To obtain disease-related datasets and ferroptosis-related genes, we utilized the GEO database and FerrDb database, respectively. Using the R software, the disease dataset was subjected to normalization, differential analysis, and GO and KEGG enrichment analysis. The differentially expressed genes from the disease dataset were then intersected with the ferroptosis-related genes to identify common genes. Core genes were selected using three machine learning algorithms, namely LASSO, SVM-RFE, and random forest. Further analysis included exploring immune infiltration correlation, predicting target drugs, and conducting molecular docking simulations. RESULTS: The differential analysis of the GSE45885 dataset yielded 1751 differentially expressed genes, while the GSE145467 dataset yielded 4358 differentially expressed genes. The intersection of these two gene sets resulted in a disease-related gene set consisting of 508 genes. Taking the intersection of the disease-related gene set and the ferroptosis-related gene set, we obtained 17 disease-related ferroptosis genes. After machine learning-based screening, three core genes were identified: GPX4, HSF1, and KLHDC3. CONCLUSION: The mechanism underlying the involvement of ferroptosis in non-obstructive azoospermia may be linked to the downregulation of GPX4, HSF1, and KLHDC3 expression. This finding provides a basis for subsequent in-depth mechanistic and therapeutic studies.


Assuntos
Azoospermia , Ferroptose , Masculino , Humanos , Azoospermia/genética , Ferroptose/genética , Simulação de Acoplamento Molecular , Biologia Computacional , Aprendizado de Máquina
14.
Front Oncol ; 12: 992346, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36483026

RESUMO

Background: Desmoplastic small round cell tumor (DSRCT) is a rare, aggressive, mesenchymal malignancy of a separate clinicopathological entity. It has a predilection for young men, with no evidence of any ethnic predilection. The current diagnostic gold standard for DSRCT includes histopathologic, immunohistochemical, and cytogenetic studies in order to confirm the variable phenotypic expression and characteristic chromosomal translocation. Case summary: A 65-year-old man presented with a sensation of an abdominal mass and a presentation of an incomplete bowel obstruction. Initial lab tests were in the normal range except for carbohydrate antigen. Contrast-enhanced CT showed that a large, mass-confounding density was occupied in the omentum majus area of the middle and lower abdominal wall. A 3D reconstruction of the images was performed to clarify the relationship between the tumor and the colon and was confirmed by a colonoscopy. After surgery, immunohistochemistry and fluorescence in situ hybridization (FISH) revealed EWSR1-WT1 gene rearrangement at 22q12, confirming the diagnosis of desmoplastic small round cell tumor. Conclusion: Being different from the predilection of DSRCT for young men, the patient in our case is a 65-year-old man with a huge mass involving the transverse colon and the bladder.

15.
Redox Biol ; 56: 102468, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36113339

RESUMO

Acute myocardial infarction (MI) triggers oxidative stress, which worsen cardiac function, eventually leads to remodeling and heart failure. Unfortunately, effective therapeutic approaches are lacking. Fibroblast growth factor 7 (FGF7) is proved with respect to its proliferative effects and high expression level during embryonic heart development. However, the regulatory role of FGF7 in cardiovascular disease, especially MI, remains unclear. FGF7 expression was significantly decreased in a mouse model at 7 days after MI. Further experiments suggested that FGF7 alleviated MI-induced cell apoptosis and improved cardiac function. Mechanistic studies revealed that FGF7 attenuated MI by inhibiting oxidative stress. Overexpression of FGF7 actives nuclear factor erythroid 2-related factor 2 (Nrf2) and scavenging of reactive oxygen species (ROS), and thereby improved oxidative stress, mainly controlled by the phosphatidylinositol-3-kinase α (PI3Kα)/AKT signaling pathway. The effects of FGF7 were partly abrogated in Nrf2 deficiency mice. In addition, overexpression of FGF7 promoted hexokinase2 (HXK2) and mitochondrial membrane translocation and suppressed mitochondrial superoxide production to decrease oxidative stress. The role of HXK2 in FGF7-mediated improvement of mitochondrial superoxide production and protection against MI was verified using a HXK2 inhibitor (3-BrPA) and a HXKII VDAC binding domain (HXK2VBD) peptide, which competitively inhibits localization of HXK2 on mitochondria. Furthermore, inhibition of PI3Kα/AKT signaling abolished regulation of Nrf2 and HXK2 by FGF7 upon MI. Together, these results indicate that the cardio protection of FGF7 under MI injury is mostly attributable to its role in maintaining redox homeostasis via Nrf2 and HXK2, which is mediated by PI3Kα/AKT signaling.


Assuntos
Infarto do Miocárdio , Fator 2 Relacionado a NF-E2 , Animais , Fator 7 de Crescimento de Fibroblastos/metabolismo , Fator 7 de Crescimento de Fibroblastos/farmacologia , Camundongos , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositóis/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxidos
16.
Radiol Artif Intell ; 4(4): e210300, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35923375

RESUMO

Purpose: To develop automated vestibular schwannoma measurements on contrast-enhanced T1- and T2-weighted MRI scans. Materials and Methods: MRI data from 214 patients in 37 different centers were retrospectively analyzed between 2020 and 2021. Patients with hearing loss (134 positive for vestibular schwannoma [mean age ± SD, 54 years ± 12;64 men] and 80 negative for vestibular schwannoma) were randomly assigned to a training and validation set and to an independent test set. A convolutional neural network (CNN) was trained using fivefold cross-validation for two models (T1 and T2). Quantitative analysis, including Dice index, Hausdorff distance, surface-to-surface distance (S2S), and relative volume error, was used to compare the computer and the human delineations. An observer study was performed in which two experienced physicians evaluated both delineations. Results: The T1-weighted model showed state-of-the-art performance, with a mean S2S distance of less than 0.6 mm for the whole tumor and the intrameatal and extrameatal tumor parts. The whole tumor Dice index and Hausdorff distance were 0.92 and 2.1 mm in the independent test set, respectively. T2-weighted images had a mean S2S distance less than 0.6 mm for the whole tumor and the intrameatal and extrameatal tumor parts. The whole tumor Dice index and Hausdorff distance were 0.87 and 1.5 mm in the independent test set. The observer study indicated that the tool was similar to human delineations in 85%-92% of cases. Conclusion: The CNN model detected and delineated vestibular schwannomas accurately on contrast-enhanced T1- and T2-weighted MRI scans and distinguished the clinically relevant difference between intrameatal and extrameatal tumor parts.Keywords: MRI, Ear, Nose, and Throat, Skull Base, Segmentation, Convolutional Neural Network (CNN), Deep Learning Algorithms, Machine Learning Algorithms Supplemental material is available for this article. © RSNA, 2022.

18.
Cell Prolif ; 55(5): e13221, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35355356

RESUMO

OBJECTIVES: Myocardial infarction (MI) commonly occurs in patients with coronary artery disease and have high mortality. Current clinical strategies for MI still limited to reducing the death of myocardial cells but failed to replace these cells. This study aimed to investigate the role of fibroblast growth factor 6 (FGF6) in enhancing the proliferative potential of cardiomyocytes (CMs) after ischemic injury via the Hippo pathway. MATERIALS AND METHODS: Expression of FGF6 protein was analysed in mice with MI induced by ligation of the left anterior descending coronary artery. Activation of the Hippo pathway and the proliferation potential were examined in ischemic CMs, treated with FGF6 protein or transfected with an adeno-virus carrying FGF6 sh-RNA. Immunofluorescence staining and western blotting were performed to assess the relationship between FGF6 and the Hippo pathway. RESULTS: We found that FGF6 expression was significantly increased in the MI mouse model. Knockdown of FGF6 synthesis resulted in poorer heart function after MI. By contrast, treatment with recombinant human FGF6 protein improved heart function, reduced infarct size, and promoted cardiac repair. Additionally, FGF6 restrains the activation of the Hippo pathway and subsequently promotes nuclear accumulation of YAP. This was largely counteracted by treatment with extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor U0126. CONCLUSION: FGF6 inhibits the Hippo pathway via ERK1/2, and facilitates nuclear translocation of YAP, and thereby promotes cardiac repair after MI.


Assuntos
Via de Sinalização Hippo , Infarto do Miocárdio , Animais , Modelos Animais de Doenças , Fator 6 de Crescimento de Fibroblastos/metabolismo , Humanos , Camundongos , Infarto do Miocárdio/terapia , Miócitos Cardíacos
19.
Cell Death Dis ; 13(3): 276, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35351862

RESUMO

Cardiac hypertrophy occurs initially in response to an increased cardiac load as a compensatory mechanism to maintain cardiac output. However, sustained pathological hypertrophy can develop into heart failure and cause sudden death. Fibroblast growth factor 20 (FGF20) is a member of the fibroblast growth factor family, which involved in apoptosis, aging, inflammation, and autophagy. The precise function of FGF20 in pathological cardiac hypertrophy is unclear. In this study, we demonstrated that FGF20 was significantly decreased in response to hypertrophic stimulation. In contrast, overexpression of FGF20 protected against pressure overload-induced cardiac hypertrophy. Mechanistically, we found that FGF20 upregulates SIRT1 expression, causing deacetylation of FOXO1; this effect promotes the transcription of downstream antioxidant genes, thus inhibits oxidative stress. In content, the anti-hypertrophic effect of FGF20 was largely counteracted in SIRT1-knockout mice, accompanied by an increase in oxidative stress. In summary, our findings reveal a previously unknown protective effect of FGF20 on pathological cardiac hypertrophy by reducing oxidative stress through activation of the SIRT1 signaling pathway. FGF20 is a potential novel molecular target for preventing and treating pressure overload-induced myocardial injury.


Assuntos
Cardiomegalia , Sirtuína 1 , Animais , Cardiomegalia/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/metabolismo , Transdução de Sinais , Sirtuína 1/genética , Sirtuína 1/metabolismo
20.
Small ; 18(7): e2106275, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35018720

RESUMO

Light-induced nonthermal strain, known as the photostrictive effect, offers a potential way to excite mechanical strain and acoustic wave remotely. The anisotropic photostrictive effect induced by the combination of bulk photovoltaic effect (BPVE) and converse piezoelectric effect in ferroelectric materials is known as too small and slow for the applications requiring a high strain rate, such as ultrasound generation and high-speed signal transmission. Here, a strategy to achieve high rate dynamic photostrictive strain by utilizing local fast responses under modulating continuous light excitation in the resonance condition is reported. A strain rate of 8.06 × 10-3  s-1 is demonstrated under continuous light excitation, which is at least one order of magnitude higher than previous studies on bulk samples as seen in the literature. The significant photostrictive response exists even in depoled ferroelectric material without overall polarization. The theoretical analyses show that fast ferroelectric photostriction can be obtained through the combinational interaction mechanism of local BPVE and local converse piezoelectric effect existing only in the microscopic scale, thus circumventing the slow and low efficient BPVE charging up process across the macroscopic electrical terminals. The achieved fast photostriction and new understandings will open new opportunities to realize future wireless signal transmission and light-acoustic devices.

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