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PURPOSE: To develop and evaluate the performance of radiomics-based computed tomography (CT) combined with machine learning algorithms in detecting occult vertebral fractures (OVFs). MATERIALS AND METHODS: 128 vertebrae including 64 with OVF confirmed by magnetic resonance imaging and 64 corresponding control vertebrae from 57 patients who underwent chest/abdominal CT scans, were included. The CT radiomics features on mid-axial and mid-sagittal plane of each vertebra were extracted. The fractured and normal vertebrae were randomly divided into training set and validation set at a ratio of 8:2. Pearson correlation analyses and least absolute shrinkage and selection operator were used for selecting sagittal and axial features, respectively. Three machine-learning algorithms were used to construct the radiomics models based on the residual features. Receiver operating characteristic (ROC) analysis was used to verify the performance of model. RESULTS: For mid-axial CT imaging, 6 radiomics parameters were obtained and used for building the models. The logistic regression (LR) algorithm showed the best performance with area under the ROC curves (AUC) of training and validation sets of 0.682 and 0.775. For mid-sagittal CT imaging, 5 parameters were selected, and LR algorithms showed the best performance with AUC of training and validation sets of 0.832 and 0.882. The LR model based on sagittal CT yielded the best performance, with an accuracy of 0.846, sensitivity of 0.846, and specificity of 0.846. CONCLUSION: Machine learning based on CT radiomics features allows for the detection of OVFs, especially the LR model based on the radiomics of sagittal imaging, which indicates it is promising to further combine with deep learning to achieve automatic recognition of OVFs to reduce the associated secondary injury.
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Fraturas Fechadas , Fraturas da Coluna Vertebral , Humanos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral , Tomografia Computadorizada por Raios X , Aprendizado de Máquina , Estudos RetrospectivosRESUMO
CCAAT enhancer-binding protein alpha (CEBPA, also known as C/EBPα) is a transcription factor that plays an essential role in regulating terminal differentiation and cell proliferation of many tissues. The objective of this study was to explore the potential function of CEBPA in ovarian cancer. The expression of CEBPA in ovarian cancer samples and adjacent normal tissues was evaluated by qRT-PCR. The putative role of CEBPA in ovarian cancer cells was evaluated by immunohistochemistry, western blot, cell viability assay, BrdU incorporation assay, soft agar colony formation assay, Transwell cell migration and invasion assay, tumor xenograft formation, and lung metastasis model. We found that CEBPA was downregulated in ovarian cancer samples and predicted a poor prognosis. CRISPR/Cas9-mediated CEBPA knockout promoted proliferation, anchorage-independent growth, migration, invasion, and EMT of ovarian cancer cells, while enforced CEPBA expression suppressed proliferation, anchorage-independent growth, migration, invasion, EMT, tumor xenograft growth, and lung metastasis of ovarian cancer cells. Furthermore, we found that the knockout of CEBPA activated Wnt/ß-catenin signaling in ovarian cancer cells, while CEBPA overexpression suppressed Wnt/ß-catenin activation. Our data indicated that CEBPA acted as a tumor suppressor in ovarian cancer, and might be a potential prognostic marker for ovarian cancer treatment.
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Transição Epitelial-Mesenquimal , Neoplasias Ovarianas , Proteína alfa Estimuladora de Ligação a CCAAT , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Ovarianas/genética , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismoRESUMO
This work describes a strategy to produce circularly polarized thermally activated delayed fluorescence (CP-TADF). A set of two structurally similar organic emitters SFST and SFOT are constructed, whose spiro architectures containing asymmetric donors result in chirality. Upon grafting within the spiro frameworks, the donor and acceptor are fixed proximally in a face-to-face manner. This orientation allows intramolecular through-space charge transfer (TSCT) to occur in both emitters, leading to TADF properties. The donor units in SFST and SFOT have a sulfur and oxygen atom, respectively; such a subtle difference has great impacts on their photophysical, chiroptical, and electroluminescence (EL) properties. SFOT exhibits greatly enhanced EL performance in doped organic light-emitting diodes, with external quantum efficiency (EQE) up to 23.1%, owing to the concurrent manipulation of highly photoluminescent quantum efficiency (PLQY, â¼90%) and high exciton utilization. As a comparison, the relatively larger sulfur atom in SFST introduces heavy atom effects and leads to distortion of the molecular backbone that lengthens the donor-acceptor distance. SFST thus has lower PLQY and faster nonradiative decay rate. The collective consequence is that the EQE value of SFST, i.e., 12.5%, is much lower than that of SFOT. The chirality of these two spiro emitters results in circularly polarized luminescence. Because SFST has a more distorted molecular architecture than SFOT, the luminescence dissymmetry factor (|glum|) of circularly polarized luminescence of one enantiomer of the former, namely, either (S)-SFST or (R)-SFST, is almost twice that of (S)-SFOT/(R)-SFOT. Moreover, the CP organic light-emitting diodes (CP-OLEDs) show obvious circularly polarized electroluminescence (CPEL) signals with gEL of 1.30 × 10-3 and 1.0 × 10-3 for (S)-SFST and (S)-SFOT, respectively.
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The ruthenium-catalyzed activation of the C4 position of coumarins for coupling with acrylates was described using modifiable ketone as a directing group. The alkenylation reaction provided a direct approach to prepare previously inaccessible 4-alkenylated coumarins with operational simplicity and high atom-economy. This protocol also worked well with coumarin-3-carboxylic acids to unveil a rare instance of a tandem alkenylation/decarboxylation reaction. The potential value of this approach was further highlighted by the efficient synthesis of several heterocyclic fused coumarin derivatives.
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BACKGROUND: To investigate the relationship between serum lipid levels and disease progression during chronic hepatitis B virus infection. METHODS: We selected 73 healthy controls and 163 patients with chronic HBV infection as the study subjects. The chronic HBV infection patients were divided into the HBV carrier group (74 patients), chronic hepatitis B group (71 patients), and liver cirrhosis group (21 patients). The age, gender, body mass index, blood lipid index, liver function index, and HBV DNA levels of all participants were tested and recorded. A t-test or the Mann-Whitney U test was used to compare the data between two groups; data from multiple groups were compared using one-way ANOVA or the Kruskal-Wallis Test. RESULTS: We observed that the serum HDL cholesterol (1.00 ± 0.30 mmol/L in the HBV-infected group, 1.29 ± 0.23 mmol/L in the control group) and APOA (1.29 ± 0.35 mmol/L, 1.36 ± 0.21 mmol/L, respectively) concentrations were significantly lower in the HBV-infected group than in the control group (p < 0.05). As the disease progressed, the blood lipid and lipoprotein values were significantly lower in the cirrhosis group TC (3.26 ± 1.00 mmol/L), HDL cholesterol (0.77 ± 0.33 mmol/L), LDL cholesterol (2.09 ± 0.62 mmol/L), and APOB (0.57 ± 0.18 mmol/L) compared with the control group, the carrier group, and the chronic hepatitis B group (p < 0.05). The serum HBV DNA level was significantly, positively correlated with the blood HDL concentration (carrier group R = 0.340, p = 0.02; chronic hepatitis B group R = 0.329, p = 0.014). There was no correlation between the HBV DNA and lipid levels in patients with cirrhosis. CONCLUSIONS: Serum lipid metabolic derangement was associated with disease progression during chronic HBV infection. Liver function and blood lipid levels were significantly lower in patients with hepatitis B-related cirrhosis.
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Hepatite B Crônica/sangue , Lipídeos/sangue , Cirrose Hepática/sangue , Testes de Função Hepática/métodos , Adulto , Índice de Massa Corporal , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Progressão da Doença , Feminino , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/complicações , Hepatite B Crônica/virologia , Humanos , Lipoproteínas/sangue , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue , Adulto JovemRESUMO
Hybrid white organic light-emitting diodes (WOLEDs) have drawn great attention both for display and solid-state lighting purposes because of the combined advantages of desirable stability of fluorescent dyes and high efficiency of phosphorescent materials. However, in most WOLEDs, obtaining high efficiency often requires complex device structures. Herein, we achieved high-efficiency hybrid WOLEDs using a simple but efficacious structure, which included a non-doped blue emissive layer (EML) to separate the exciton recombination zone from the light emission region. After optimization of the device structure, the WOLEDs showed a maximum power efficiency (PE), current efficiency (CE), and external quantum efficiency (EQE) of 82.3 lm/W, 70.0 cd/A, and 22.2%, respectively. Our results presented here provided a new option for promoting simple-structure hybrid WOLEDs with superior performance.
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Luz , Modelos TeóricosRESUMO
Interneurons in the olfactory bulb (OB) are generated from neuronal precursor cells migrating from anterior subventricular zone (SVZa) not only in the developing embryo but also throughout the postnatal life of mammals. In the present study, we established an in vivo electroporation assay to label SVZa cells of rat both at embryonic and postnatal ages, and traced SVZa progenitors and followed their migration pathway and differentiation. We found that labeled cells displayed high motility. Interestingly, the postnatal cells migrated faster than the embryonic cells after applying this assay at different ages of brain development. Furthermore, based on brain slice culture and time-lapse imaging, we analyzed the detail migratory properties of these labeled precursor neurons. Finally, tissue transplantation experiments revealed that cells already migrated in subependymal zone of OB were transplanted back into rostral migratory stream (RMS), and these cells could still migrate out tangentially along RMS to OB. Taken together, these findings provide an in vivo labeling assay to follow and trace migrating cells in the RMS, their maturation and integration into OB neuron network, and unrecognized phenomena that postnatal SVZa progenitor cells with higher motility than embryonic cells, and their migration was affected by extrinsic environments.
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Encéfalo/citologia , Encéfalo/embriologia , Movimento Celular , Eletroporação/métodos , Animais , Animais Recém-Nascidos , Diferenciação Celular , Forma Celular , Proteínas de Fluorescência Verde/metabolismo , Ventrículos Laterais/citologia , Células-Tronco Neurais/citologia , Bulbo Olfatório/citologia , Ratos Sprague-Dawley , Coloração e RotulagemRESUMO
BACKGROUND: Alcohol abuse is a serious health problem worldwide that causes a variety of physical and mental disorders. Research has shown that the brain-derived neurotrophic factor (BDNF) plays an important role in alcohol addiction. The BDNF precursor (proBDNF) exhibits different actions than BDNF through separate receptors and pathways in the central nervous system. However, the effects of proBDNF and BDNF in alcohol addiction are not fully known. OBJECTIVES: The objective was to identify the expression patterns and effects of proBDNF and BDNF after chronic alcohol exposure. METHODS: A total of 40 male adult mice were studied. A mouse psychomotor sensitization (PS) model was established to explore the effects of BDNF and proBDNF treatment following chronic alcohol exposure. Reverse transcription PCR (RT-PCR) was performed to measure mRNA levels for BDNF, TrkB, P75NTR, and sortilin in the prefrontal cortex, hippocampus, and dorsal striatum of Kunming mice after chronic alcohol exposure. RESULTS: In Kunming mice, chronic alcohol exposure up-regulated BDNF and TrkB mRNA levels in the prefrontal cortex, but decreased sortilin and P75 mRNA levels in the dorsal striatum. No changes in mRNA levels were found in other measured brain regions in the alcohol and control groups. CONCLUSION: Chronic alcohol exposure induced the region-specific expression of BDNF and proBDNF and their respective receptors in the brain. These results suggest that BDNF and proBDNF signaling pathways may play major roles in alcohol preference and addiction.
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Fator Neurotrófico Derivado do Encéfalo/metabolismo , Corpo Estriado/efeitos dos fármacos , Etanol/administração & dosagem , Hipocampo/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Receptor trkB/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Corpo Estriado/metabolismo , Hipocampo/metabolismo , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Regulação para CimaRESUMO
OBJECTIVE: To study the association between depression during pregnancy and low birth weight in neonates, and to provide a scientific basis for the prevention of low birth weight. METHODS: Cohort studies on the association between depression during pregnancy and low birth weight were collected and a Meta analysis was performed. Data were extracted independently by two investigators, and quality assessment was performed according to Newcastle-Ottawa Scale. The Egger's test was used to evaluate publication bias. RESULTS: A total of 12 cohort studies with 37 192 samples were included. The results of the Meta analysis showed that depression during pregnancy was associated with low birth weight (Z=2.08, P=0.038), and the neonates whose mothers had depression during pregnancy tended to have a high risk of low birth weight (RR=1.303, 95%CI: 1.015-1.672). The sensitivity analysis showed that the results of this Meta analysis were stable and reliable, and the Egger's test showed no publication bias. CONCLUSIONS: Depression during pregnancy may be a risk factor for low birth weight in neonates.
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Depressão/complicações , Recém-Nascido de Baixo Peso , Complicações na Gravidez , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , GravidezRESUMO
OBJECTIVE: To investigate the major risk factors for congenital heart disease (CHD) in Chinese neonates and to provide a reference for the prevention of CHD. METHODS: A literature search was performed to collect the case-control studies on the risk factors for CHD in Chinese neonates published in 2001-2016. The relevant data were extracted accordingly. The quality of included studies was assessed by Newcastle-Ottawa Scale. Sensitivity analysis was conducted using different models to analyze the same data. The publication bias was assessed by Egger's test. RESULTS: A total of 17 case-control studies involving 2 930 cases and 4 952 controls were included. The Meta analysis showed that the major risk factors for CHD in Chinese neonates were as follows: mother with advanced age (OR=2.649, 95%CI: 1.675-4.189), cold or fever (OR=4.558, 95%CI: 2.901-7.162), medication use in early pregnancy (OR=3.961, 95%CI: 2.816-5.573), passive smoking (OR=2.766, 95%CI: 1.982-3.859), abnormal childbearing history (OR=2.992, 95%CI: 1.529-5.856), noise exposure (OR=3.030, 95%CI: 1.476-6.217), radiation exposure (OR=2.363, 95%CI: 1.212-4.607), decoration (OR=4.979, 95%CI: 3.240-7.653), gestational diabetes (OR=5.090, 95%CI: 3.132-8.274), and pet raising (OR=2.048, 95%CI: 1.385-3.029). CONCLUSIONS: Mothers with advanced age, cold or fever, medication use in early pregnancy, passive smoking, abnormal childbearing history, noise exposure, radiation exposure, decoration, gestational diabetes, and pet raising may increase the risk of CHD in Chinese neonates.
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Cardiopatias Congênitas/etiologia , Estudos de Casos e Controles , Humanos , Recém-Nascido , Fatores de RiscoRESUMO
Brain-derived neurotrophic factor (BDNF) plays important roles in neural stem cell (NSC) growth. In this study, we investigated whether BDNF exerts its neurotrophic effects through the Wnt/ß-catenin signaling pathway in human embryonic spinal cord NSCs (hESC-NSCs) in vitro. We found an increase in hESC-NSC growth by BDNF overexpression. Furthermore, expression of Wnt1, Frizzled1 and Dsh was upregulated, whereas GSK-3ß expression was downregulated. In contrast, hESC-NSC growth was decreased by BDNF RNA interference. BDNF, Wnt1 and ß-catenin components were all downregulated, whereas GSK-3ß was upregulated. Next, we treated hESC-NSCs with 6-bromoindirubin-3'-oxime (BIO), a small molecule inhibitor of GSK-3ß. BIO reduced the effects of BDNF upregulation/downregulation on the cell number, soma size and differentiation, and suppressed the effect of BDNF modulation on the Wnt signaling pathway. Our findings suggest that BDNF promotes hESC-NSC growth in vitro through crosstalk with the Wnt/ß-catenin signaling pathway, and that this interaction may be mediated by GSK-3ß.
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Fator Neurotrófico Derivado do Encéfalo/genética , Proliferação de Células , Células-Tronco Embrionárias/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Células-Tronco Neurais/metabolismo , Via de Sinalização Wnt , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Células Cultivadas , Células-Tronco Embrionárias/fisiologia , Receptores Frizzled/genética , Receptores Frizzled/metabolismo , Humanos , Células-Tronco Neurais/fisiologia , Regulação para Cima , beta Catenina/metabolismoRESUMO
The development of methods for the asymmetric synthesis of N-N axial chirality remains elusive and challenging. Here, we disclose a method for the construction of N-N axially chiral pyrrolyl-oxoisoindolins along with central chirality via the isothiourea (ITU)-catalyzed acylative dynamic kinetic resolution (DKR). Axial chirality was introduced into the acylative DKR of hemiaminals for the first time. This protocol features mild conditions with excellent yields and enantioselectivities.
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Peanut skin (PS) contains various flavonoids and phenols that have antitumor and antioxidant effects. However, no research has been conducted on PS and hepatocellular carcinoma (HCC). Therefore, this study sought to explore the potential mechanism of PS in treating HCC. PS was searched for in the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform and SYMMAP databases. HCC targets were searched for in five major databases. Protein-protein interaction network, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes analyses were performed. Molecular docking and molecular dynamics simulation were used for verification. Furthermore, in vitro experiments were used to verify the regulation of PS on human HCC (HepG2) cells. Ten ingredients and 95 common targets were identified for PS and HCC, respectively. The key targets of ingredients mainly relate to pathways such as hepatitis B, lipid and atherosclerosis, advanced glycation end products (AGEs)-AGE receptors (RAGEs) signaling pathway in diabetic complications, interleukin-17 (IL-17) signaling pathway, mitogen activated kinase-like protein (MAPK) signaling pathway, the PI3K-Akt signaling pathway. In addition, the molecular docking and molecular dynamics simulation analysis indicated the ingredients had strong binding ability with the targets. Moreover, in vitro experiments confirmed that luteolin can promote the apoptosis of HepG2 cells by controlling the expression of phosphorylated protein-tyrosine kinase (p-AKT). This study provides preliminary evidence that PS produces a marked effect in regulating multiple signaling pathways in HCC through multiple ingredients acting on multiple core genes, including AKT serine/threonine kinase 1 (AKT1), MYC, caspase 3 (CASP3), estrogen receptor 1 (ESR1), epidermal growth factor receptor (EGFR), jun proto-oncogene(JUN), and provides the basis for follow-up research to verify the mechanism of action of PS in treating HCC.
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Carcinoma Hepatocelular , Medicamentos de Ervas Chinesas , Neoplasias Hepáticas , Humanos , Arachis , Carcinoma Hepatocelular/tratamento farmacológico , Farmacologia em Rede , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Neoplasias Hepáticas/tratamento farmacológicoRESUMO
Immobilized enzymes exhibit favorable advantages in biocatalysis, such as high operation stability, feasible reusability, and improved organic solvents tolerance. Herein, an immobilized ω-amine transaminase AtATA@MWCNTs-NH2 is successfully prepared using amino modified multi-walled carbon nanotubes as carrier and glutaraldehyde as crosslinker. Under the optimum immobilization conditions, the activity recovery is 78.7%. Compared with purified enzyme AtATA, AtATA@MWCNTs-NH2 possesses superior stability, even in harsh conditions (e.g., high temperature, acidic or alkali environment, and different kind of organic solvents). To simplify the separation and extraction of products, we choose methanol (10%, v/v) as the cosolvent, replacing DMSO (20%, v/v) in our previous work, for the catalytic reaction of AtATA@MWCNTs-NH2. AtATA@MWCNTs-NH2 can be used for stereoselective synthesis (R)-(+)- 1(1-naphthyl)ethylamine ((R)-NEA) for 15 cycles, with the e.e.p (enantiomeric excess) > 99.5%. The catalytic process of AtATA@MWCNTs-NH2 achieves cycle production of (R)-NEA using methanol as cosolvent.
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Nanotubos de Carbono , Naftalenos , Aminas , Transaminases , Metanol , Enzimas Imobilizadas , Etilaminas , SolventesRESUMO
BACKGROUND: Thyroid nodules are common lesions in benign and malignant thyroid diseases. More and more studies have been conducted on the feasibility of artificial intelligence (AI) in the detection, diagnosis, and evaluation of thyroid nodules. The aim of this study was to use bibliometric methods to analyze and predict the hot spots and frontiers of AI in thyroid nodules. METHODS: Articles on the application of artificial intelligence in thyroid nodules were retrieved from the Web of Science core collection database. A website (https://bibliometric.com/), VOSviewer and CiteSpace software were used for bibliometric analyses. The collaboration maps of countries and institutions were analyzed. The cluster and timeline view based on cocitation references and keywords citation bursts visualization map were generated. RESULTS: The study included 601 papers about AI in thyroid nodules. China contributed to more than half (52.41%) of these publications. The cluster view and timeline view of co-citation references were assembled into 9 clusters, "AI", "deep learning", "papillary thyroid carcinoma", "radiomics", "ultrasound image", "biomarkers", "medical image segmentation", "central lymph node metastasis (CLNM)", and "self-organizing auto-encoder". The "AI", "radiomics", "medical image segmentation", "deep learning," and "CLNM", emerging in the last 10 years and continuing until recent years, were included. CONCLUSION: An increasing number of scholars were devoted to this field. The potential future research hotspots include risk factor assessment and CLNM prediction of thyroid carcinoma based on radiomics and deep learning, automatic segmentation based on medical images (especially ultrasound images).
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The EUV imager is used to observe the 30.4 nm radiation of the earth's plasmasphere on the lunar surface. The 30.4 nm multilayer is the key optical part of the imager. According to the technical parameters, the B4 C/Mg, B4 C/Mg2Si, B4 C/Al, B4 C/Si, Mo/Si and so on were chosen. The period thickness, ratio of the material and the number of the periods were optimized and the reflectivity of those multilayers were calculated. In consideration of the lunar environment, the Mo/Si and the B4 C/Si multilayer were deposited by magnetron sputtering coating plant. The reflectivity of Mo/Si and B4 C/Si multilayer at 30.4 nm is 15.3% and 22.8% respectively.
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BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is a common type of tumor that can metastasize to any organs and sites. However, it is extremely rare for ccRCC to metastasize to the iris. Here, we describe a rare case of iris metastasis from ccRCC with a history of left nephrectomy in 2010. CASE SUMMARY: A 62-year-old male was admitted to the hospital due to blurred vision and red eyes, and a mass was found on the iris in the right eye. B-scan ultrasonography revealed a well-bounded high-density lesion at the corner of the anterior chamber at the 3-4 o'clock position. Phacoemulsification with simultaneous intraocular lens implantation and iridocyclectomy was performed in the right eye. The lesion was confirmed to be metastatic ccRCC by histological and immunohistochemical analyses. The patient was still alive at 9 mo after surgical treatment. Ocular metastasis can be an initial sign with a poor prognosis. Timely detection and treatment may improve survival. Clinicians should pay attention to similar metastatic diseases to prevent misdiagnosis leading to missed treatment opportunities. CONCLUSION: This report of the characteristics and successful management of a rare case of iris metastasis from ccRCC highlights the importance of a comprehensive medical history, histopathology, immunohistochemistry, and clinical manifestation for successful disease diagnosis.
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RATIONALE AND OBJECTIVES: To explore the feasibility of the preoperative prediction of pathological central lymph node metastasis (CLNM) status in patients with negative clinical lymph node (cN0) papillary thyroid carcinoma (PTC) using a computed tomography (CT) radiomics signature. MATERIALS AND METHODS: A total of 97 PTC cN0 nodules with CLNM pathology data (pN0, with CLNM, n = 59; pN1, without CLNM, n = 38) in 85 patients were divided into a training set (n = 69) and a validation set (n = 28). For each lesion, 321 radiomic features were extracted from nonenhanced, arterial and venous phase CT images. Minimum redundancy and maximum relevance and the least absolute shrinkage and selection operator were used to find the most important features with which to develop a radiomics signature in the training set. The performance of the radiomics signature was evaluated by receiver operating characteristic curves, calibration curves and decision curve analysis . RESULTS: Three nonzero the least absolute shrinkage and selection operator coefficient features were selected for radiomics signature construction. The radiomics signature for distinguishing the pN0 and pN1 groups achieved areas under the curve of 0.79 (95% CI 0.67, 0.91) in the training set and 0.77 (95% CI 0.55, 0.99) in the validation set. The calibration curves demonstrated good agreement between the radiomics score-predicted probability and the pathological results in the two sets (p= 0.399, p = 0.191). The decision curve analysis curves showed that the model was clinically useful. CONCLUSION: This radiomic signature could be helpful to predict CLNM status in cN0 PTC patients.
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Neoplasias da Glândula Tireoide , Tomografia Computadorizada por Raios X , Humanos , Câncer Papilífero da Tireoide/diagnóstico por imagem , Câncer Papilífero da Tireoide/patologia , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Curva ROC , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/patologia , Estudos Retrospectivos , Linfonodos/patologiaRESUMO
A novel strategy for the synthesis of 2-arylethenesulfonyl fluorides from nitrones and ethenesulfonyl fluoride (ESF) by the activation of the C-H bond using an inexpensive and readily available Ru-catalyst has been developed. In this process, the directing group can be concomitantly converted to an amide group. Interestingly, changing the substituent of the nitrogen of nitrones from a tert-butyl to a methyl group resulted in the formation of cyclic isoindolinones. Detailed mechanistic studies are also presented.
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The Rh(III)-catalyzed dual directing group assisted C-H activation/annulation of 3-arylisoxazolones with propargyl alcohols has been developed, which expands the application scope of isoxazolones in organic synthesis. This protocol also worked well with 3-aryl-1,4,2-dioxazol-5-ones to produce synthetically and biologically important 4-arylisoquinolones.