RESUMO
The electrocatalytic oxidation of organic molecules coupled with hydrogen evolution reaction can reduce overpotential and can be connected in series with nonelectrochemical processes to achieve the preparation of more high-value compounds. Herein, Cu- and Co-incorporated nickel hydroxide (CuCo-Ni(OH)2) was synthesized and applied to the anodic benzylamine oxidation reaction, which is 280 mV lower than the corresponding oxygen evolution reaction to reach the current density of 50 mA cm-2. When the electrocatalytic oxidation of benzylamine and hydrogen evolution reaction are coupled to form an electrolytic cell, the potential to reach 10 mA cm-2 is reduced by 197 mV compared to the overall water splitting. The benzylamine is converted to benzamide with 99.3% conversion and 90.2% faraday efficiency under 1.45 V constant voltage electrolysis, and the catalytic performance remains at a high level after 4 cycles. The characterization and density functional theory calculations show that Cu and Co share the transfer charge from Ni, making it easy for CuCo-Ni(OH)2 to deprotonate Ni-O* sites. The formed Ni-O* sites exhibit lower energy barriers in the proton transfer of benzylamine to benzonitrile and hydration intermediates, resulting in a better catalytic performance of CuCo-Ni(OH)2 than Ni(OH)2 in the electrocatalytic oxidation of benzylamine to benzamide.
RESUMO
PURPOSE: To explore the static and dynamic characteristics of intrinsic brain activity (IBA) in subcortical ischemic vascular disease (SIVD) patients with or without cognitive impairment. METHODS: In total, 90 participants were recruited, including 32 SIVD patients with cognitive impairment (SIVD-CI, N = 32), 26 SIVD patients with no cognitive impairment (SIVD-NCI, N = 26), and 32 healthy controls (HC, N = 32) matched for age, gender, and education. All subjects underwent resting-state functional magnetic resonance imaging (rs-fMRI) scanning and neuropsychological tests. Amplitude of low-frequency fluctuation (ALFF) was calculated to reflect static alterations of regional IBA. Sliding window analysis was conducted in order to explore the dynamic characteristics. RESULTS: Both SIVD-CI and SIVD-NCI group showed significantly decreased ALFF in left angular gyrus (ANG), whereas SIVD-CI group showed increased ALFF in right superior frontal gyrus (SFG), compared with HCs. Furthermore, SIVD-CI group showed significantly decreased ALFF dynamics (dALFF) in right precuneus (PreCu) and left dorsal anterior cingulate cortex (dACC), compared with HC and SIVD-NCI groups (Gaussian random field-corrected, voxel-level P < 0.001, cluster-level P < 0.05). No dynamic changes were detected between SIVD-NCI group and HC group. The mean ALFF value in left ANG of SIVD-CI group was correlated with the score of delayed memory scale. CONCLUSION: ANG may be a vulnerable brain region in SIVD patients. Temporal dynamic analysis could serve as a sensitive and promising method to investigate IBA alterations in SIVD patients.
Assuntos
Imageamento por Ressonância Magnética , Doenças Vasculares , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Giro do CínguloRESUMO
Introduction: The incidence of thyroid diseases has increased in recent years, and cervical lymph node metastasis (LNM) is considered an important risk factor for locoregional recurrence. This study aims to develop a deep learning-based computer-aided diagnosis (CAD) method to diagnose cervical LNM with thyroid carcinoma on computed tomography (CT) images. Methods: A new deep learning framework guided by the analysis of CT data for automated detection and classification of LNs on CT images is proposed. The presented CAD system consists of two stages. First, an improved region-based detection network is designed to learn pyramidal features for detecting small nodes at different feature scales. The region proposals are constrained by the prior knowledge of the size and shape distributions of real nodes. Then, a residual network with an attention module is proposed to perform the classification of LNs. The attention module helps to classify LNs in the fine-grained domain, improving the whole classification network performance. Results: A total of 574 axial CT images (including 676 lymph nodes: 103 benign and 573 malignant lymph nodes) were retrieved from 196 patients who underwent CT for surgical planning. For detection, the data set was randomly subdivided into a training set (70%) and a testing set (30%), where each CT image was expanded to 20 images by rotation, mirror image, changing brightness, and Gaussian noise. The extended data set included 11,480 CT images. The proposed detection method outperformed three other detection architectures (average precision of 80.3%). For classification, ROI of lymph node metastasis labeled by radiologists were used to train the classification network. The 676 lymph nodes were randomly divided into 70% of the training set (73 benign and 401 malignant lymph nodes) and 30% of the test set (30 benign and 172 malignant lymph nodes). The classification method showed superior performance over other state-of-the-art methods with an accuracy of 96%, true positive and negative rates of 98.8 and 80%, respectively. It outperformed radiologists with an area under the curve of 0.894. Discussion: The extensive experiments verify the high efficiency of the proposed method. It is considered instrumental in a clinical setting to diagnose cervical LNM with thyroid carcinoma using preoperative CT images. The future research can consider adding radiologists' experience and domain knowledge into the deep-learning based CAD method to make it more clinically significant. Conclusion: The extensive experiments verify the high efficiency of the proposed method. It is considered instrumental in a clinical setting to diagnose cervical LNM with thyroid carcinoma using preoperative CT images.
RESUMO
BACKGROUND: We aimed to investigate risk factors for the presence and number of cerebral microbleeds (CMBs) in patients with different stages of hypertension stages, with an emphasis on the relationship between white matter changes (WMCs) and CMBs. METHODS: Since 2016, participants aged 40 years or more have been evaluated for the presence of CMBs using enhanced 3D multiecho GE T2*-weighted angiography (ESWAN) sequences. The Mann-Whitney U test and Pearson χ2 test were used to compare the clinical characteristics between the CMB and no-CMB patient groups. Furthermore, we used Spearman's rank correlation analysis to examine the associations between the degree of CMB severity and other important factors. RESULTS: CMBs were detected in 110 (36.7%) of 300 participants. Among patients with stage 2 hypertension, the majority also had CMBs (61.8%, 68/110). CMBs were positively correlated with age, hypertension stage, duration of hypertension, WMCs, and silent cerebral infarction. Patients with grade 3 WMCs were significantly more likely to have CMBs than those without WMCs; this association was true for both patients with stage 1 and those with stage 2 hypertension. In patients with stage 1 or stage 2 hypertension lasting longer than 20 years, the majority had CMBs (69.0%, 29/42; 69.1%, 47/68). The results of binary logistic regression indicated that a more severe hypertension stage, longer duration of hypertension, aging, having silent cerebral infarction and higher values of WMC increase the likelihood of the occurrence of CMBs. CONCLUSIONS: CMBs detected in hypertensive patients were more likely to occur in deep structures, and the grade of WMCs and duration of hypertension were more closely associated with the CMB degree than with age.
RESUMO
In this investigation, ammonium polyphosphate (APP) is applied to suppress the deflagration of sucrose dust. Through the systematic research on flame propagation images and temperature, decomposition behavior of powder samples and the compositions of deflagration residue, the suppression performance and mechanism of APP on sucrose deflagration are profoundly summarized. Timing diagrams show that APP contributes to reduce deflagration flame brightness, increases ignition delay time and flame fault area. The minimum inerting concentration of APP for sucrose deflagration is determined to be 8 %. From the collected deflagration flame temperature curves, it is confirmed that APP can delay peak temperature arrival time, weaken temperature fluctuation, and decrease peak values of flame temperature and temperature rising rate. Through the analysis on thermal decomposition of samples and deflagration residue, it is reflected that APP has superior composite suppression effect. It can not only absorb reaction heat, but also decrease deflagration exotherm to improve thermal stability of sucrose particles. Thus, the easily oxidized components in sucrose are protected, and deflagration intensity is effectively weakened. This work provides a new solution for prevention and suppression deflagration of dust waste in sugar industry.
RESUMO
BACKGROUND: To explore the clinical value of texture analysis of MR images (multiphase Gd-EOB-DTPA-enhanced MRI and T2 weighted imaging (T2WI) to identify the differentiated degree of hepatocellular carcinoma (HCC). METHOD: One hundred four participants were enrolled in this retrospective study. Each participant performed preoperative Gd-EOB-DTPA-enhanced MR scanning. Texture features were analyzed by MaZda, and B11 program was used for data analysis and classification. The diagnosis efficiencies of texture features and conventional imaging features in identifying the differentiated degree of HCC were assessed by receiver operating characteristic analysis. The relationship between texture features and differentiated degree of HCC was evaluated by Spearman's correlation coefficient. RESULTS: The grey-level co-occurrence matrix -based texture features were most frequently extracted and the nonlinear discriminant analysis was excellent with the misclassification rate ranging from 3.33 to 14.93%. The area under the curve (AUC) of the combined texture features between poorly- and well-differentiated HCC, poorly- and moderately-differentiated HCC, moderately- and well-differentiated HCC was 0.812, 0.879 and 0.808 respectively, while the AUC of tumor size was 0.649, 0.660 and 0.517 respectively. The tumor size was significantly different between poorly- and moderately-HCC (p = 0.014). The COMBINE AUC values were not increased with tumor size combined. CONCLUSIONS: Texture analysis of Gd-EOB-DTPA-enhanced MRI and T2WI was valuable and might be a promising method in identifying the differentiated degree of HCC. The poorly-differentiated HCC was more heterogeneous than well- and moderately-differentiated HCC.
Assuntos
Carcinoma Hepatocelular/diagnóstico , Processamento de Imagem Assistida por Computador , Neoplasias Hepáticas/diagnóstico , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Idoso , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Meios de Contraste/administração & dosagem , Feminino , Gadolínio DTPA/administração & dosagem , Hepatectomia , Humanos , Fígado/patologia , Fígado/cirurgia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , SoftwareRESUMO
A ratiometric electrochemical aptamer-based assay is described for the ultrasensitive and highly specific determination of adenosine triphosphate (ATP). It is based on ATP aptamer-mediated triple-helix molecular switch (THMS). The method uses (a) a hairpin DNA (MB-DNA-SH) labeled with the redox probe Methylene Blue (MB) at the 3' end, and a thiol group at the 5' end, and (b) a single strand ATP aptamer modified with two ferrocenes at each end (Fc-DNA-Fc). The labeled probe of type MB-DNA-SH was self-assembled onto the surface of a gold electrode via gold-thiol binding. On exposure to Fc-DNA-Fc, it will hybridize with MB-DNA-SH to form a stable THMS structure on electrode surface. In the presence of ATP, it hybridizes with the loop portion of Fc-DNA-Fc, and this results in the unwinding of the THMS structure. Such variation caused the changes of the differential pulse voltammetry (DPV) peak currents of both MB (at around -0.25 V) and Fc (at around 0.39 V; both vs. Ag/AgCl). A significant enhancement is found for the ratio of the two DPV peaks. Under the optimum experimental conditions, this assay has a response that covers the 0.05 to 100 pM ATP concentration range, and the detection limit is 5.2 fM (for S/N = 3). The method is highly selective for ATP over its analogs. Graphical abstract Schematic presentation of a novel ratiometric electrochemical aptasensor for ATP via triple-helix molecular switch (THMS) strategy. MB-DNA-SH was self-assembled on GE surface through gold-thiol binding. Fc-DNA-Fc hybridized with MB-DNA-SH to form THMS structure. ATP specifically bond with its aptamer sequence of Fc-DNA-Fc to unwind the THMS structure. The ratio of DPV peak currents of MB and Fc was applied to monitor the concentration of ATP in real samples over its analogs.
RESUMO
Gastric cancer is one of the leading causes of cancer-related deaths worldwide. Among which, about 1%-3% of gastric cancer patients were characterized by inherited gastric cancer predisposition syndromes, knowing as hereditary diffuse gastric cancer (HDGC). Studies reported that CDH1 germline mutations are the main cause of HDGC. With the help of rapid development of genetic testing technologies and data analysis tools, more and more researchers focus on seeking candidate susceptibility genes for hereditary cancer syndromes. In addition, National Comprehensive Cancer Network (NCCN) guidelines recommend that the patients of HDGC carrying CDH1 mutations should undergo prophylactic gastrectomy or routine endoscopic surveillances. Therefore, genetic counseling plays a key role in helping individuals with pathogenic mutations make appropriate risk management plans. Moreover, experienced and professional genetic counselors as well as a systematic multidisciplinary team (MDT) are also required to facilitate the development of genetic counseling and benefit pathogenic mutation carriers who are in need of regular and standardized risk management solutions. In this review, we provided an overview about the germline mutations of several genes identified in HDGC, suggesting that these genes may potentially act as susceptibility genes for this malignant cancer syndrome. Furthermore, we introduced information for prevention, diagnosis and risk management of HDGC. Investigations on key factors that may have effect on risk management decision-making and genetic data collection of more cancer syndrome family pedigrees are required for the development of HDGC therapeutic strategies.
RESUMO
Wnt1-inducible signaling pathway protein-1 is a cysteine-rich protein that belongs to the CCN family, which has been implicated in mediating the occurrence and progression through distinct molecular mechanisms in several tumor types. However, the association of Wnt1-inducible signaling pathway protein-1 with gastric cancer and the related molecular mechanisms remain to be elucidated. Therefore, this study aimed to clarify the biological role of Wnt1-inducible signaling pathway protein-1 in the proliferation, migration, and invasion in gastric cancer cells and further investigated the associated molecular mechanism on these biological functions. We first detected the expression level of Wnt1-inducible signaling pathway protein-1 in gastric cancer, and the reverse transcription polymerase chain reaction have shown that Wnt1-inducible signaling pathway protein-1 expression levels were upregulated in gastric cancer tissues. The expression of Wnt1-inducible signaling pathway protein-1 in gastric cancer cell lines was also detected by quantitative real-time polymerase chain reaction and Western blotting. Furthermore, two gastric cancer cell lines with high expression of Wnt1-inducible signaling pathway protein-1 were selected to explore the biological function of Wnt1-inducible signaling pathway protein-1 in gastric cancer. Function assays indicated that knockdown of Wnt1-inducible signaling pathway protein-1 suppressed cell proliferation, migration, and invasion in BGC-823 and AGS gastric cancer cells. Further investigation of mechanisms suggested that cyclinD1 was identified as one of Wnt1-inducible signaling pathway protein-1 related genes to accelerate proliferation in gastric cancer cells. In addition, one pathway of Wnt1-inducible signaling pathway protein-1 induced migration and invasion was mainly through the enhancement of epithelial-to-mesenchymal transition progression. Taken together, our findings presented the first evidence that Wnt1-inducible signaling pathway protein-1 was upregulated in gastric cancer and acted as an oncogene by promoting proliferation, migration, and invasion in gastric cancer cells.
Assuntos
Biomarcadores Tumorais/biossíntese , Proteínas de Sinalização Intercelular CCN/biossíntese , Proliferação de Células/genética , Proteínas Proto-Oncogênicas/biossíntese , Neoplasias Gástricas/genética , Biomarcadores Tumorais/genética , Proteínas de Sinalização Intercelular CCN/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Proteínas Proto-Oncogênicas/genética , Transdução de Sinais , Neoplasias Gástricas/patologiaRESUMO
BACKGROUND: KIAA1199 was upregulated in diverse cancers, but the association of KIAA1199 with gastric cancer (GC), the biological role of KIAA1199 in GC cells and the related molecular mechanisms remain to be elucidated. METHODS: KIAA1199 expression was analysed by reverse transcription-polymerase chain reaction assay (RT-PCR) and immunohistochemistry (IHC) in GC patient tissue. The small hairpin RNA (shRNA) was applied for the knockdown of endogenous KIAA1199 in NCI-N87 and AGS cells. MTT, colony formation, scratch wounding migration, transwell chamber migration and invasion assays were employed respectively to investigate the role of KIAA1199 in GC cells. The potential signaling pathway of KIAA1199 induced migration and invasion was detected. RESULTS: KIAA1199 was upregulated in GC tissue and was an essential independent marker for poor prognosis. Knockdown KIAA1199 suppressed the proliferation, migration and invasion in GC cells. KIAA1199 stimulated the Wnt/ß-catenin signaling pathway and the enzymatic activity of matrix metalloproteinase (MMP) family members and thus accelerated the epithelial-to-mesenchymal transition (EMT) progression in GC cells. CONCLUSION: These findings demonstrated that KIAA1199 was upregulated in GC tissue and associated with worse clinical outcomes in GC, and KIAA1199 acted as an oncogene by promoting migration and invasion through the enhancement of Wnt/ß-catenin signaling pathway and MMPs mediated EMT progression in GC cells.
Assuntos
Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Metaloproteinase 2 da Matriz/genética , Proteínas/genética , Neoplasias Gástricas/genética , beta Catenina/genética , Idoso , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal/genética , Feminino , Humanos , Hialuronoglucosaminidase , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Proteínas/antagonistas & inibidores , Proteínas/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Análise de Sobrevida , Via de Sinalização Wnt , beta Catenina/metabolismoRESUMO
Wnt-1 inducible signaling pathway-1 (WISP-1), also known as CCN-4, belongs to the connective tissue growth factor (CTGF) family. WISP-1 is primarily expressed in embryonic stem cells and is involved in adult organ development. WISP-1 participates in many cellular processes, including proliferation, differentiation, apoptosis and adhesion. In addition, WISP-1 plays an important role in diverse pathophysiological processes, such as embryonic development, inflammation, injury repairs and cancers. Recent studies showed that WISP-1 was highly correlated with tumor progression and malignant transformation, whereas it played an oncogenic role in colorectal cancer, cholangiocarcinoma, hepatocellular carcinoma and breast cancer. However, interestingly, WISP-1 exerts a tumor-suppressing role in lung and prostate cancers. WISP-1 promotes cell proliferation, adhesion, motility, invasion, metastasis and epithelial-to-mesenchymal transition via particular signaling pathways. In this review, we discussed the structure, expression profile, functions, clinical significance and potential mechanisms of WISP-1 in cancer and non-neoplastic diseases.
RESUMO
Tobacco samples of a same cultivar grown in different plantations in China were evaluated for their chemical compositions at different maturities for the first time. This was accomplished by a comprehensive and reliable method using gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography-photodiode array-quadrupole time-of-flight mass spectrometry (HPLC-PDA-QTOF-MS) to analyze the fat-soluble and polar components in 12 batches of tobacco samples of three origins and four maturities. The GC-MS analyses showed that tobacco samples harvested at 40 days after transplantation exhibited more fat-soluble components, while those harvested at 100 days after transplantation exhibited the least fat-soluble components. Tentatively, identification of the main components as well as quantitative analyses of eight reference compounds, including five alkaloids, two polyphenols, and a coumarin, was performed by the developed HPLC-QTOF-PDA method. Results showed significant differences among origins and maturities in the contents of these compounds. The nicotine contents showed great variety among the 12 tobacco samples. The highest nicotine content were found in a sample from Zhengzhou harvested at 40 days after transplantation (ZZ-T with 25399.39 ± 308.95 µg/g), and the lowest nicotine level was detected in a sample from Zunyi harvested at 60 days after transplantation (ZY-X with 1654.49 ± 34.52 µg/g). The highest level of rutin was found in a Jiangchuan sample harvested at 60 days after transplantation (JC-X with 725.93 ± 40.70 µg/g), and the lowest rutin content was detected in a Zunyi tobacco sample harvested at 60 days after transplantation (ZY-X with 87.42 ± 2.78 µg/g). The developed method provided a convenient approach which might be applied for rapid maturity evaluation and tobacco flavor identification and also holds the potential for analysis of compounds present in other plants.