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1.
Plant Biotechnol J ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38864414

RESUMO

With global climate change, it is essential to find strategies to make crops more resistant to different stresses and guarantee food security worldwide. E3 ubiquitin ligases are critical regulatory elements that are gaining importance due to their role in selecting proteins for degradation in the ubiquitin-proteasome proteolysis pathway. The role of E3 Ub ligases has been demonstrated in numerous cellular processes in plants responding to biotic and abiotic stresses. E3 Ub ligases are considered a class of proteins that are difficult to control by conventional inhibitors, as they lack a standard active site with pocket, and their biological activity is mainly due to protein-protein interactions with transient conformational changes. Proteolysis-targeted chimeras (PROTACs) are a new class of heterobifunctional molecules that have emerged in recent years as relevant alternatives for incurable human diseases like cancer because they can target recalcitrant proteins for destruction. PROTACs interact with the ubiquitin-proteasome system, principally the E3 Ub ligase in the cell, and facilitate proteasome turnover of the proteins of interest. PROTAC strategies harness the essential functions of E3 Ub ligases for proteasomal degradation of proteins involved in dysfunction. This review examines critical advances in E3 Ub ligase research in plant responses to biotic and abiotic stresses. It highlights how PROTACs can be applied to target proteins involved in plant stress response to mitigate pathogenic agents and environmental adversities.

2.
J Exp Bot ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38912636

RESUMO

Recent research findings established the cruciality of Cys2/His2-type Zinc Finger Proteins (C2H2-ZFPs) in plant growth and their relevance in coping with various stressors. Nevertheless, the complex structure of the C2H2-ZFPs network and the molecular mechanisms of response to stress in adversity have received considerable attention and now require more in-depth examination. This paper reviews the structural characteristics, classification, and recent functional research advances of C2H2-ZFPs. In addition, it systematically introduces the roles of these proteins across diverse facets of plant biology, encompassing growth and development, responses to biotic and abiotic stresses, and laying the foundation for future functional studies of C2H2-ZFPs.

3.
Neurocrit Care ; 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253924

RESUMO

BACKGROUND: External ventricular drain (EVD) is used for monitoring intracranial pressure or diverting cerebrospinal fluid. However, confirmation of an infection is not immediate and requires obtaining culture results, often leading to the excessive use of antibiotics. This study aimed to compare noninfectious ventriculitis and EVD infection in terms of the risk factors, predictors, prognosis, and effectiveness of care bundle interventions. METHODS: This retrospective study was conducted at a medical center with 1,006 beds in northern Taiwan between January 2018 and July 2022. Standard EVD insertion protocols and care bundles have been implemented since 2018, along with the initiation of chlorhexidine. RESULTS: In total, 742 EVD cases were identified. Noninfectious ventriculitis typically presents with fever approximately 8 days following EVD placement, whereas EVD infection typically manifests as fever after 20 days. Aneurysmal subarachnoid hemorrhage was strongly associated with the development of noninfectious ventriculitis (adjusted odds ratio [OR] 2.6, 95% confidence interval [CI] 1.5-4.4). Alcoholism (adjusted OR 3.5, 95% CI 1.1-12.3) and arteriovenous malformation (adjusted OR 13.1, 95% CI 2.9-58.2) significantly increased the risk of EVD infection. The EVD infection rate significantly decreased from 3.6% (14 of 446) to 1.0% (3 of 219) (p = 0.03) after the implementation of chlorhexidine gluconate bathing. CONCLUSIONS: Aneurysmal subarachnoid hemorrhage or fever with neuroinflammation within 2 weeks of EVD placement is indicative of a higher likelihood of noninfectious ventriculitis. Conversely, patients with arteriovenous malformation, alcoholism, or fever with neuroinflammation occurring after more than 3 weeks of EVD placement are more likely to necessitate antibiotic treatment for EVD infection. Chlorhexidine gluconate bathing decreases EVD infection.

4.
Sensors (Basel) ; 23(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37299943

RESUMO

Surface plasmon resonance (SPR) sensing is a real-time detection technique for measuring biomolecular interactions on gold surfaces. This study presents a novel approach using nano-diamonds (NDs) on a gold nano-slit array to obtain an extraordinary transmission (EOT) spectrum for SPR biosensing. We used anti-bovine serum albumin (anti-BSA) to bind NDs for chemical attachment to a gold nano-slit array. The covalently bound NDs shifted the EOT response depending on their concentration. The number of ND-labeled molecules attached to the gold nano-slit array was quantified from the change in the EOT spectrum. The concentration of anti-BSA in the 35 nm ND solution sample was much lower than that in the anti-BSA-only sample (approximately 1/100). With the help of 35 nm NDs, we were able to use a lower concentration of analyte in this system and obtained better signal responses. The responses of anti-BSA-linked NDs had approximately a 10-fold signal enhancement compared to anti-BSA alone. This approach has the advantage of a simple setup and microscale detection area, which makes it suitable for applications in biochip technology.


Assuntos
Técnicas Biossensoriais , Ressonância de Plasmônio de Superfície , Técnicas Biossensoriais/métodos , Ouro/química , Soroalbumina Bovina/química , Ressonância de Plasmônio de Superfície/métodos , Nanotecnologia , Diamante
5.
Horm Metab Res ; 54(2): 94-103, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35130570

RESUMO

Glycated hemoglobin (HbA1c) variability is emerging as an indicator of long-term glycemic control, which may play a significant role during vascular complications. We conducted a systematic review and meta-analysis to assess the association between the scope of HbA1c variability and vascular complications in patients with type 2 diabetes mellitus. PubMed and Embase were searched for studies that evaluated the association of HbA1c variability with vascular complications in patients with type 2 diabetes. Two reviewers independently completed data extraction. Random-effects meta-analysis was conducted with stratification according to the type of vascular complications. Nine studies were eligible for inclusion in our systematic review and meta-analysis. Six studies evaluated the impact of the standard deviation of HbA1c (HbA1c-SD) on cardiovascular events and showed an association of HbA1c-SD with cardiovascular events (HR: 1.25, 95% CI 1.18-1.32, 5 studies). Six studies evaluated renal disease associated with HbA1c-SD and showed that HbA1c-SD was correlated with an increased risk of renal disease (HR: 1.19, 95% CI 1.13-1.24). Two studies evaluated HbA1c-SD and the risk of retinopathy and showed that no significant association was found between retinopathy and HbA1c-SD (HR 1.08, 95% CI 0.92-125). For HbA1c-SD ranging from 0.6 to 0.8%, HbA1c-SD was associated with an increased risk of cardiovascular events (HR: 1.25, 95% CI 1.15-1.35) and renal disease (HR: 1.16, 95% CI 1.11-1.22). For individuals with index HbA1c variability greater than or equal to 0.6%, HbA1c variability was significantly associated with vascular complications in patients with type 2 diabetes mellitus.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Glicemia/análise , Doenças Cardiovasculares/complicações , Diabetes Mellitus Tipo 2/complicações , Hemoglobinas Glicadas/análise , Humanos , Estudos Prospectivos
6.
Sensors (Basel) ; 22(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36080864

RESUMO

Detecting pesticides using techniques that involve simple fabrication methods and conducting the detection at very low levels are challenging. Herein, we report the detection of acetamiprid at the quadrillionth level using surface-enhanced Raman scattering (SERS). The SERS chip comprises Ag nanoparticles deposited on a tetrapod structure of ZnO coated onto indium tin oxide glass (denoted as Ag@ZnO-ITO). Controlled Ag decoration of ZnO occurs via irradiation-induced synthesis. The morphology of the surface plays a significant role in achieving an enhanced SERS performance for acetamiprid detection. 4,4'-Dipyridyl (DPY) is used to investigate synthesis conditions for the chip, leading to an optimal irradiation time of 60 min. Furthermore, the enhancement factor for acetamiprid on Ag@ZnO-ITO is higher than 107. These results demonstrate that SERS sensors have the potential for practical use in acetamiprid detection.


Assuntos
Nanopartículas Metálicas , Praguicidas , Óxido de Zinco , Nanopartículas Metálicas/química , Neonicotinoides , Praguicidas/análise , Prata/química , Análise Espectral Raman/métodos , Óxido de Zinco/química
7.
Appl Opt ; 57(16): 4570-4575, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29877363

RESUMO

An ultrabroadband, high linearity directly modulated laser (DML) module operated at the O-band is proposed. The effect of the package network on the DML module is first investigated. In the package network, a wire bonding compensation method is used to improve the resonance at high frequency, which can be equivalent to the channel equalization technique. Without any optical amplification, we experimentally demonstrated 90 Gb/s four-level pulse amplitude modulation transmission over 40 km standard single mode fiber, which is the longest reach to the best of our knowledge. A bit error rate of 6.74×10-4 is achieved at a received optical power of -2.5 dBm. A receiver sensitivity of -4.5 dBm at 7% overhead forward error correction limit (3.8×10-3) is obtained for back-to-back with a power margin of more than 8.5 dB.

8.
Opt Express ; 24(14): 16132-48, 2016 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-27410880

RESUMO

A rigorous full-vector multi-mode fiber (MMF) model is proposed. It is believed to be the first comparative study of vector and scalar MMF model in terms of differential mode delay (DMD), mode power distribution (MPD), transfer functions as well as eye diagrams. It shows that the vector nature of fiber modes cannot be ignored even though the refractive index difference can be as small as 1%. A standard-compliant methodology for MMF characterization is introduced. The impact of fiber parameters on bandwidth is studied. The statistical transfer function model of OM3 and OM4 fiber is provided. These transfer functions can be applied to the MMF link modeling. Rigorous full-vector MMF model is an essential tool for research and development of MMF link transceivers and standard development of 112Gbps and beyond.

9.
Plants (Basel) ; 13(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38611501

RESUMO

In this study, an innovative approach based on multimodal data and the transformer model was proposed to address challenges in agricultural disease detection and question-answering systems. This method effectively integrates image, text, and sensor data, utilizing deep learning technologies to profoundly analyze and process complex agriculture-related issues. The study achieved technical breakthroughs and provides new perspectives and tools for the development of intelligent agriculture. In the task of agricultural disease detection, the proposed method demonstrated outstanding performance, achieving a precision, recall, and accuracy of 0.95, 0.92, and 0.94, respectively, significantly outperforming the other conventional deep learning models. These results indicate the method's effectiveness in identifying and accurately classifying various agricultural diseases, particularly excelling in handling subtle features and complex data. In the task of generating descriptive text from agricultural images, the method also exhibited impressive performance, with a precision, recall, and accuracy of 0.92, 0.88, and 0.91, respectively. This demonstrates that the method can not only deeply understand the content of agricultural images but also generate accurate and rich descriptive texts. The object detection experiment further validated the effectiveness of our approach, where the method achieved a precision, recall, and accuracy of 0.96, 0.91, and 0.94. This achievement highlights the method's capability for accurately locating and identifying agricultural targets, especially in complex environments. Overall, the approach in this study not only demonstrated exceptional performance in multiple tasks such as agricultural disease detection, image captioning, and object detection but also showcased the immense potential of multimodal data and deep learning technologies in the application of intelligent agriculture.

10.
Chemosphere ; 358: 142237, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705406

RESUMO

In this study, a novel Ce2MgMoO6/CNFs (cerium magnesium molybdite double perovskite decorated on carbon nanofibers) nanocomposite was developed for selective and ultra-sensitive detection of ciprofloxacin (CFX). Physical characterization and analytical techniques were used to explore the morphology, structure, and electrocatalytic characteristics of the Ce2MgMoO6/CNFs nanocomposite. The sensor has a wide linear range (0.005-7.71 µM and 9.75-77.71 µM), a low limit of detection (0.012 µM), high sensitivity (0.807 µA µM-1 cm-2 nM), remarkable repeatability, and an appreciable storage stability. Here, we used density functional theory to investigate CFX and oxidized CFX as well as the locations of the energy levels and electron transfer sites. Furthermore, the Ce2MgMoO6/CNFs-modified electrode was successfully tested in food samples (milk and honey), indicating an acceptable response with a recovery percentage and relative standard deviation of less than 4%, which is comparable to that of GC-MS. Finally, the developed sensor exhibited high selectivity and stability for CFX detection.


Assuntos
Carbono , Ciprofloxacina , Mel , Leite , Nanocompostos , Nanofibras , Óxidos , Nanocompostos/química , Ciprofloxacina/análise , Ciprofloxacina/química , Óxidos/química , Leite/química , Nanofibras/química , Animais , Mel/análise , Carbono/química , Molibdênio/química , Limite de Detecção , Compostos de Cálcio/química , Titânio/química , Teoria da Densidade Funcional , Técnicas Eletroquímicas/métodos , Cério/química , Contaminação de Alimentos/análise , Eletrodos , Magnésio/química , Magnésio/análise
11.
Food Chem ; 455: 139920, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38850994

RESUMO

This work presents a hydrothermal method followed by a sonochemical treatment for synthesizing tantalum decorated on iron selenide (Ta/FeSe2) integrated with nitrogen-doped graphene (NGR) as a susceptible electrode material for detecting trolox (TRX) in berries samples. The surface morphology, structural characterizations, and electrochemical performances of the synthesized Ta/FeSe2/NGR composite were analyzed via spectrophotometric and voltammetry techniques. The GCE modified with Ta/FeSe2/NGR demonstrated an impressive linear range of 0.1 to 580.3 µM for TRX detection. Additionally, it achieved a remarkable limit of detection (LOD) of 0.059 µM, and it shows a high sensitivity of 2.266 µA µÐœ-1 cm-2. Here, we used density functional theory (DFT) to investigate the structures of TRX and TRX quinone and the locations of energy levels and electron transfer sites. The developed sensor exhibits significant selectivity, satisfactory cyclic and storage stability, and notable reproducibility. Moreover, the practicality of TRX was assessed in different types of berries, yielding satisfactory recoveries.

12.
Environ Pollut ; 356: 124196, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38788992

RESUMO

This study involved the synthesis of a Ce2Sn2O7/Ag3PO4/V@g-C3N4 composite through hydrothermal methods, followed by mechanical grinding. The resulting heterojunction exhibited improved catalytic activity under visible light by effectively separating electrons and holes (e-/h+). The degradation of Tartrazine (TTZ) reached 93.20% within 50 min by employing a ternary composite at a concentration of 10 mg L-1, along with 6 mg L-1 of PS. The highest pseudo-first-order kinetic constant (0.1273 min-1 and R2 = 0.951) was observed in this system. The dual Z-scheme heterojunction is developed by Ce2Sn2O7, Ag3PO4, and V@g-C3N4, and it may increase the visible light absorption range while also accelerating charge carrier transfer and separation between catalysts. The analysis of the vulnerability positions and degradation pathways of TTZ involved the utilization of density functional theory (DFT) and gas chromatography-mass spectrometry (GC-MS) to examine the intermediate products. Therefore, Ce2Sn2O7/Ag3PO4/V@g-C3N4 is an excellent ternary nanocomposite for the remediation of pollutants.

13.
J Clin Med ; 12(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37048551

RESUMO

Proton pump inhibitors (PPIs) are widely prescribed in medical practice for the treatment of several gastrointestinal disorders. Previous epidemiology studies have reported the association between PPI use and the risk of AKI, although the magnitude of the association between PPIs and the risk of acute kidney injury (AKI) remains uncertain. Therefore, we conducted a meta-analysis to determine the relationship between PPI therapy and the risk of AKI. We systematically searched for relevant articles published before January 2023 on PubMed, Scopus, and Web of Science. In addition, we conducted a manual search of the bibliographies of potential articles. Two independent reviewers examined the appropriateness of all studies for inclusion. We pooled studies that compared the risk of AKI with PPI against their control using a random effect model. The search criteria based on PRISMA guidelines yielded 568 articles. Twelve observational studies included 2,492,125 individuals. The pooled adjusted RR demonstrated a significant positive association between PPI therapy and the risk of AKI (adjusted RR 1.75, 95% CI: 1.40-2.19, p < 0.001), and it was consistent across subgroups. A visual presentation of the funnel plot and Egger's regression test showed no evidence of publication bias. Our meta-analysis indicated that persons using PPIs exhibited an increased risk of AKI. North American individuals had a higher risk of AKI compared to Asian and European individuals. However, the pooled effect from observational studies cannot clarify whether the observed association is a causal effect or the result of some unmeasured confounding factors. Hence, the biological mechanisms underlying this association are still unclear and require further research.

14.
Front Neurol ; 14: 1149236, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37213896

RESUMO

Managing acute innominate artery (IA) dissection associated with severe stenosis is challenging due to its rarity, possible complex dissection patterns, and compromised blood flow to the brain and upper extremities. This report describes our treatment strategy for this challenging disease using the kissing stent technique. A 61-year-old man had worsening of an acute IA dissection secondary to an extension of a treated aortic dissection. Four possible treatment strategies for kissing stent placement were proposed based on different approaches (open surgical or endovascular) and accesses (trans-femoral, trans-brachial, or trans-carotid access). We chose to place two stents simultaneously via a percutaneous retrograde endovascular approach through the right brachial artery and a combined open surgical distal clamping of the common carotid artery with a retrograde endovascular approach through the carotid artery. This hybrid approach strategy highlights the three key points for maintaining safety and efficacy: (1) good guiding catheter support is obtainable through retrograde, rather than antegrade, access to the lesion, (2) concomitant cerebral and upper extremity reperfusion is guaranteed by placing kissing stents into the IA, and (3) peri-procedural cerebral emboli are prevented by surgical exposure of the common carotid artery with distal clamping.

15.
Clin Neuroradiol ; 33(2): 319-325, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36056108

RESUMO

PURPOSE: Rete middle cerebral artery (MCA) anomaly is characterized by a web-like network of arteries involving the first MCA segment (M1) and a normal downstream MCA. The detailed composition of this anomaly and the hemodynamic impacts on cerebral perfusion are rarely addressed. The purpose of this study was to elucidate the anatomical and hemodynamic perspectives of the rete MCA anomaly. METHODS: From August 2020 to December 2021, 4 rete MCA anomalies were identified at Shuang Ho hospital. Clinical information, perfusion magnetic resonance (MR) imaging, and angiographic images were collected. Detailed angioarchitecture, including types of arterial feeders and extent of rete involvement, were analyzed based on three-dimensional volume-rendering reconstruction images obtained from the catheter-based angiographies. RESULTS: Despite their variable clinical presentations (two hemorrhage, one ischemia, and one asymptomatic), all cases shared common angiographic findings as follows: (1) the internal carotid artery did not connect directly to the rete, (2) the anterior choroidal artery (AChA) was the artery constantly supplying the rete and (3) there was a watershed zone shift toward MCA territory. The perfusion MR cerebral blood flow map was symmetric in all studied cases. CONCLUSION: The AChA is an artery constantly supplying the rete, which suggests that the angioarchitectural features associated with this anomaly may be the result of both congenital and acquired compensatory processes. Cerebral perfusion remains preserved at the lesion side, despite angiographic evidence of watershed zone shift. These findings will be important for making better clinical judgments about this condition.


Assuntos
Relevância Clínica , Artéria Cerebral Média , Humanos , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/cirurgia , Artérias Cerebrais , Artéria Carótida Interna , Angiografia por Ressonância Magnética , Angiografia Cerebral
16.
Front Plant Sci ; 14: 1230517, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37680364

RESUMO

Introduction: Sugarcane stem node detection is one of the key functions of a small intelligent sugarcane harvesting robot, but the accuracy of sugarcane stem node detection is severely degraded in complex field environments when the sugarcane is in the shadow of confusing backgrounds and other objects. Methods: To address the problem of low accuracy of sugarcane arise node detection in complex environments, this paper proposes an improved sugarcane stem node detection model based on YOLOv7. First, the SimAM (A Simple Parameter-Free Attention Module for Convolutional Neural Networks) attention mechanism is added to solve the problem of feature loss due to the loss of image global context information in the convolution process, which improves the detection accuracy of the model in the case of image blurring; Second, the Deformable convolution Network is used to replace some of the traditional convolution layers in the original YOLOv7. Finally, a new bounding box regression loss function WIoU Loss is introduced to solve the problem of unbalanced sample quality, improve the model robustness and generalization ability, and accelerate the convergence speed of the network. Results: The experimental results show that the mAP of the improved algorithm model is 94.53% and the F1 value is 92.41, which are 3.43% and 2.21 respectively compared with the YOLOv7 model, and compared with the mAP of the SOTA method which is 94.1%, an improvement of 0.43% is achieved, which effectively improves the detection performance of the target detection model. Discussion: This study provides a theoretical basis and technical support for the development of a small intelligent sugarcane harvesting robot, and may also provide a reference for the detection of other types of crops in similar environments.

17.
J Surg Case Rep ; 2021(8): rjab334, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34405041

RESUMO

Vertebro-venous fistula (VVF) refers to an abnormal arteriovenous shunt connecting the extracranial vertebral artery and the paraspinal venous structures. Coil embolization is the mainstay treatment of choice for VVF, and accurate definition of the endovascular target is mandatory. Traditionally, catheter-based angiograms are used for treatment planning, but those images lack bony information to delineate the precise relationship of the drainage veins to the spinal structure. Herein, we presented two VVF cases and demonstrated how we used intra-arterial cone-beam computed tomography angiography (IA-CBCTA) to determine the safe embolization zone for dense coil packing. We propose that IA-CBCTA is a useful adjunct in the endovascular planning of VVF by offering an image consisting of bony and vascular information.

18.
Opt Express ; 18(20): 20595-609, 2010 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-20940954

RESUMO

To facilitate the analysis of radiation mode couplings, quasi leaky mode approximations were utilized in coupled-mode analysis. The key to effectively and accurately apply this approach is how to well approximate radiation modes by the quasi leaky modes in an equivalent closed waveguide model. In this paper, the principle, applicability and accuracy of the approximations are demonstrated, and the detailed implementation is also suggested by applying a unified coupled-mode analysis to fiber gratings. First of all, based on a thorough study on the characteristics of the complex modes, for the first time, quasi leaky modes are classified into guided-mode-like inner-cladding and radiation-mode-like outer-cladding leaky modes so as to explicitly establish equivalence relationships between the discrete leaky modes and the continuous radiation modes. With this new insight, the whole analysis process especially for some of the practically tricky issues such as the criteria for developing the proper equivalent waveguide model and the subsequent mode expansion basis are better understood and easier to be dealt with for different problems where radiation modes come into play. Moreover, as essential preconditions to extend the conventional coupled mode analysis to the present unified one, the couplings between the guided core mode and a leaky mode are studied in a systematic and consistent manner. An intuitive and then a deep understanding on the roles of complex modes on mode coupling and power exchanging are thus gained for further simulations. Lastly, the transmission spectra of fiber gratings with different surrounding indices are simulated. The simulated results agree well with those obtained theoretically and experimentally in the literatures, which strongly validate the principle of quasi leaky mode approximations and its implementation on the unified coupled-mode analysis expounded in this paper.

19.
Opt Express ; 18(2): 713-26, 2010 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-20173891

RESUMO

A full vector complex coupled mode theory (CMT) for the analysis of tilted fiber gratings is presented. With the combination of the perfectly matched layer (PML) and the perfectly reflecting boundary (PRB), the continuous radiation modes are well represented by a set of discrete complex modes. Simulation of coupling to radiation modes is greatly simplified and may be treated in the same fashion as guided modes. Numerical results of the tilted fiber Bragg gratings (TFBGs) with outer-cladding index equal, lower and higher than that of the inner-cladding indicate that the complex coupled mode approach is highly effective in the simulation of couplings to cladding and radiation modes in tilted fiber gratings. The reflective TFBGs are investigated by the proposed approach in detail.


Assuntos
Modelos Teóricos , Refratometria/instrumentação , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Rotação , Espalhamento de Radiação
20.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(1): 34-41, 2020 Jan 30.
Artigo em Zh | MEDLINE | ID: mdl-32376554

RESUMO

OBJECTIVE: To investigate the expression of signal transduction and activator of transcription 2 (STAT2) in ovarian cancer and its correlation with the prognosis of ovarian cancer patients and explore the role of STAT2 inregulating metastasis of ovarian cancer cells. METHODS: RT-qPCR was performed to detect the expression of STAT2 mRNA in 62 fresh frozen ovarian cancer tissues and 62 normal ovarian tissues; immunohistochemistry was used to detect STAT2 protein expressions in 95 paraffin-embedded ovarian cancer samples and 33 normal ovarian tissues. Kaplan-Meier method was used to analyze the correlation between the expression of STAT2 and the prognosis of the patients. We also examined the relationship between STAT2 and the patients' prognosis by analyzing the data in Kaplan-Meier Plotter database. Western blotting was performed to detect the expression of STAT2 in different ovarian cancer cell lines. In A2780 cells with the highest STAT2 expression, we examined the effects of STAT2 interference on cell migration and invasiveness using Transwell migration assay and on the expressions of the downstream molecule epidermal growth factor receptor (EGFR). RESULTS: Ovarian cancer tissues expressed significantly higher levels of STAT2 mRNA than normal ovarian tissue. A high STAT2 mRNA expression was correlated with an advanced FIGO stage. Immunohistochemistry showed that 67.4% of the ovarian cancer samples, as compared with 28.3% of normal ovarian tissues, showed high STAT2 expressions. In ovarian cancer patients, a high expression of STAT2 protein was associated with ascites volume, distant metastasis and FIGO stage (P < 0.05). Survival analysis showed that ovarian cancer patients with a high expression of STAT2 protein had poor overall survival (P=0.021) and progression-free survival (P=0.018). STAT2 was overexpressed in all the ovarian cancer cell lines tested, and A2780 cell lines showed the highest expression. Interference of STAT2 significantly suppressed the migration and invasiveness (P < 0.01) and lowered the expression level of EGFR in A2780 cells. CONCLUSIONS: STAT2 is overexpressed in ovarian cancer. A high expression of STAT2 is associated with a poor prognosis of ovarian cancer patients. STAT2 may promote the metastasis of ovarian cancer by enhancing the expression of EGFR.


Assuntos
Metástase Neoplásica , Neoplasias Ovarianas/patologia , Fator de Transcrição STAT2/genética , Biomarcadores Tumorais , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Prognóstico
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