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PURPOSE: To develop an automated deep learning model for MRI-based segmentation and detection of intracranial arterial calcification. METHODS: A novel deep learning model under the variational autoencoder framework was developed. A theoretically grounded dissimilarity loss was proposed to refine network features extracted from MRI and restrict their complexity, enabling the model to learn more generalizable MR features that enhance segmentation accuracy and robustness for detecting calcification on MRI. RESULTS: The proposed method was compared with nine baseline methods on a dataset of 113 subjects and showed superior performance (for segmentation, Dice similarity coefficient: 0.620, area under precision-recall curve [PR-AUC]: 0.660, 95% Hausdorff Distance: 0.848 mm, Average Symmetric Surface Distance: 0.692 mm; for slice-wise detection, F1 score: 0.823, recall: 0.764, precision: 0.892, PR-AUC: 0.853). For clinical needs, statistical tests confirmed agreement between the true calcification volumes and predicted values using the proposed approach. Various MR sequences, namely T1, time-of-flight, and SNAP, were assessed as inputs to the model, and SNAP provided unique and essential information pertaining to calcification structures. CONCLUSION: The proposed deep learning model with a dissimilarity loss to reduce feature complexity effectively improves MRI-based identification of intracranial arterial calcification. It could help establish a more comprehensive and powerful pipeline for vascular image analysis on MRI.
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Aprendizado Profundo , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Feminino , Masculino , Pessoa de Meia-Idade , Algoritmos , Calcificação Vascular/diagnóstico por imagem , Idoso , Processamento de Imagem Assistida por Computador/métodos , Interpretação de Imagem Assistida por Computador/métodos , Adulto , Encéfalo/diagnóstico por imagemRESUMO
Growth factor receptor bound protein 7 (GRB7) is reportedly upregulated in human gastric cancer (GC), which is closely associated with tumor progression and prognosis. However, the mechanism underlying its dysregulation in GC remains poorly understood. In this study, we found that GRB7 overexpression was associated with Helicobacter pylori (H. pylori) infection. GC cells (AGS and MGC-803) infection assays revealed that this upregulation was mediated by the transcription factor STAT3, and activation of STAT3 by H. pylori promoted GRB7 expression in infected GC cells. Moreover, CagA, the key virulence factor of H. pylori, was found involved in STAT3-mediated GRB7 overexpression. The overexpressed GRB7 further promoted GC cell proliferation, migration, and invasion by activating ERK signaling. Mice infection was further used to investigate the action of GRB7. In H. pylori infection, GRB7 expression in mice gastric mucosa was elevated, and higher STAT3 and ERK activation were also detected. These results revealed GRB7-mediated pathogenesis in H. pylori infection, in which H. pylori activates STAT3, leading to increased GRB7 expression, then promotes activation of the ERK signal, and finally enhances malignant properties of infected cells. Our findings elucidate the role of GRB7 in H. pylori-induced gastric disorders, offering new prospects for the treatment and prevention of H. pylori-associated gastric carcinogenesis by targeting GRB7.
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Plasmid conjugation is a central mechanism driving the dissemination of antibiotic resistance in Klebsiella pneumoniae. However, the conjugative operon requires specific stimuli for activation. Identifying signals and elucidating the underlying mechanisms is crucial in combating plasmid spread. This study uncovers a key mechanism promoting the dissemination of high-risk plasmids, including IncFII, IncX3, and IncX4 types, in K. pneumoniae. We observed that increased donor density significantly enhanced conjugation, and transcript levels of both conjugation and AI-2 quorum sensing genes were markedly upregulated. By mutating the luxS and lsrR genes in K. pneumoniae 1678, we found that plasmid conjugation efficiency decreased in the 1678ΔluxS mutant, while it significantly increased in the 1678ΔlsrR mutant. RT-qPCR and ß-galactosidase assays demonstrated that LsrR represses transcription of relaxosome and T4CP genes, while AI-2 (synthesized by LuxS) activates their expression. AlphaFold3 docking models suggest LsrR may bind directly to IncX plasmid relaxase promoters, inhibiting their expression. Adding external AI-2 signals revealed no effect on plasmid conjugation when LsrR was absent, confirming the dependence of AI-2 signals on LsrR repression. In conclusion, AI-2-mediated signaling enhances donor density effects on plasmid conjugation by de-repressing LsrR-mediated suppression.
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Electrical stimulation has been used clinically as an adjunct therapy to accelerate the healing of bone defects, and its mechanism requires further investigations. The complexity of the physiological microenvironment makes it challenging to study the effect of electrical signal on cells alone. Therefore, an artificial system mimicking cell microenvironment in vitro was developed to address this issue. In this work, a novel electrical stimulation system was constructed based on polypyrrole nanowires (ppyNWs) with a high aspect ratio. Synthesized ppyNWs formed a conductive network in the composited hydrogel which contained modified gelatin with methacrylate, providing a conductive cell culture matrix for bone marrow mesenchymal stem cells. The dual-network conductive hydrogel had improved mechanical, electrical, and hydrophilic properties. It was able to imitate the three-dimensional structure of the cell microenvironment and allowed adjustable electrical stimulations in the following system. This hydrogel was integrated with cell culture plates, platinum electrodes, copper wires, and external power sources to construct the artificial electrical stimulation system. The optimum voltage of the electrical stimulation system was determined to be 2 V, which exhibited remarkable biocompatibility. Moreover, this system had significant promotion in cell spreading, osteogenic makers, and bone-related gene expression of stem cells. RNA-seq analysis revealed that osteogenesis was correlated to Notch, BMP/Smad, and calcium signal pathways. It was proven that this biomimetic system could regulate the osteogenesis procedure, and it provided further information about how the electrical signal regulates osteogenic differentiations.
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Diferenciação Celular , Estimulação Elétrica , Células-Tronco Mesenquimais , Nanofios , Osteogênese , Pirróis , Osteogênese/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Diferenciação Celular/efeitos dos fármacos , Nanofios/química , Pirróis/química , Pirróis/farmacologia , Polímeros/química , Polímeros/farmacologia , Animais , Hidrogéis/química , Hidrogéis/farmacologia , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Células Cultivadas , Biomimética/métodos , RatosRESUMO
This study concentrates on the segmentation of intracranial aneurysms, a pivotal aspect of diagnosis and treatment planning. We aim to overcome the inherent instance imbalance and morphological variability by introducing a novel morphology and texture loss reweighting approach. Our innovative method involves the incorporation of tailored weights within the loss function of deep neural networks. Specifically designed to account for aneurysm size, shape, and texture, this approach strategically guides the model to focus on capturing discriminative information from imbalanced features. The study conducted extensive experimentation utilizing ADAM and RENJI TOF-MRA datasets to validate the proposed approach. The results of our experimentation demonstrate the remarkable effectiveness of the introduced methodology in improving aneurysm segmentation accuracy. By dynamically adapting to the variances present in aneurysm features, our model showcases promising outcomes for accurate diagnostic insights. The nuanced consideration of morphological and textural nuances within the loss function proves instrumental in overcoming the challenge posed by instance imbalance. In conclusion, our study presents a nuanced solution to the intricate challenge of intracranial aneurysm segmentation. The proposed morphology and texture loss reweighting approach, with its tailored weights and dynamic adaptability, proves to be instrumental in enhancing segmentation precision. The promising outcomes from our experimentation suggest the potential for accurate diagnostic insights and informed treatment strategies, marking a significant advancement in this critical domain of medical imaging.
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Electrochemical nitrate reduction to ammonia (ENO3RR) has attracted great attention owing to its characteristics of treating wastewater while producing high value-added ammonia. In this study, we successfully prepared a heterojunction electrocatalyst Fe2O3/ZnO consisting of Fe2O3 nanosheets and ZnO nanoparticles, where the construction of the Fe2O3/ZnO heterojunction not only increased the exposure of the active sites of the catalyst, accelerated the interfacial electron transfer, and improved the conductivity of the catalyst but also optimized its overall electronic structure. Thus, Fe2O3/ZnO demonstrated a high Faraday efficiency of 97.4% and an ammonia yield of 6327.2 µg h-1 cm-2 at -1.0 V (vs. RHE) in 0.1 M KNO3 and 0.1 M PBS. DFT calculations also confirmed that the constructed Fe2O3/ZnO heterojunction effectively decreased the reaction energy barrier of *NO â *NHO and accelerated the reaction kinetics, which is favourable for ENO3RR. This study provides a new and facile design strategy of catalysts for electrochemical nitrate reduction to ammonia.
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The impact of elevated CO2 levels on microorganisms is a focal point in studying the environmental effects of global climate change. A growing number of studies have demonstrated the importance of the direct effects of elevated CO2 on microorganisms, which are confounded by indirect effects that are not easily identified. Riparian zones have become key factor in identifying the environmental effects of global climate change because of their special location. However, the direct effects of elevated CO2 levels on microbial activity and function in riparian zone sediments remain unclear. In this study, three riparian sediments with different pollution risk levels of heavy metals and nutrients were selected to explore the direct response of microbial communities and functions to elevated CO2 excluding plants. The results showed that the short-term effects of elevated CO2 did not change the diversity of the bacterial and fungal communities, but altered the composition of their communities. Additionally, differences were observed in the responses of microbial functions to elevated CO2 levels among the three regions. Elevated CO2 promoted the activities of nitrification and denitrification enzymes and led to significant increases in N2O release in the three sediments, with the greatest increase of 76.09 % observed in the Yuyangshan Bay (YYS). Microbial carbon metabolism was promoted by elevated CO2 in YYS but was significantly inhibited by elevated CO2 in Gonghu Bay and Meiliang Bay. Moreover, TOC, TN, and Pb contents were identified as key factors contributing to the different microbial responses to elevated CO2 in sediments with different heavy metal and nutrient pollution. In conclusion, this study provides in-depth insights into the responses of bacteria and fungi in polluted riparian sediments to elevated CO2, which helps elucidate the complex interactions between microbial activity and environmental stressors.
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Helicobacter pylori infection has been thought to be associated with liver diseases, although the exact mechanisms remain elusive. This study identified H. pylori-induced liver inflammation and tissue damage in infected mice and examined the exosome-mediated mechanism underlying H. pylori infection's impact on liver injury. Exosomes were isolated from H. pylori-infected gastric epithelial GES-1 cells (Hp-GES-EVs), and the crucial virulence factor CagA was identified within these exosomes. Fluorescent labeling demonstrated that Hp-GES-EVs can be absorbed by liver cells. Treatment with Hp-GES-EVs enhanced the proliferation, migration, and invasion of Hep G2 and Hep 3B cells. Additionally, exposure to Hp-GES-EVs activated NF-κB and PI3K/AKT signaling pathways, which provides a reasonable explanation for the liver inflammation and neoplastic traits. Using a mouse model established via tail vein injection of Hp-GES-EVs, exosome-driven liver injury was evidenced by slight hepatocellular erosion around the central hepatic vein and elevated serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and IL-6. Administering the exosome inhibitor GW4869 via intraperitoneal injection in mice resulted in a reduction of liver damage caused by H. pylori infection. These findings illuminate the exosome-mediated pathogenesis of H. pylori-induced liver injury and offer valuable insights into the extra-gastrointestinal manifestations of H. pylori infection.
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Antígenos de Bactérias , Proteínas de Bactérias , Modelos Animais de Doenças , Exossomos , Infecções por Helicobacter , Helicobacter pylori , Fígado , Transdução de Sinais , Exossomos/metabolismo , Animais , Infecções por Helicobacter/complicações , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/metabolismo , Helicobacter pylori/patogenicidade , Camundongos , Humanos , Proteínas de Bactérias/metabolismo , Fígado/patologia , Fígado/metabolismo , Fígado/microbiologia , Antígenos de Bactérias/metabolismo , Compostos de Benzilideno/farmacologia , Compostos de Anilina/farmacologia , NF-kappa B/metabolismo , Células Hep G2 , Aspartato Aminotransferases/sangue , Interleucina-6/metabolismo , Alanina Transaminase/sangue , Proliferação de Células , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Células Epiteliais/microbiologia , Células Epiteliais/metabolismo , Movimento Celular , Linhagem Celular , Masculino , Fatores de Virulência/metabolismoRESUMO
Recent studies have suggested that irregular pulsation of intracranial aneurysm during the cardiac cycle may be potentially associated with aneurysm rupture risk. However, there is a lack of quantification method for irregular pulsations. This study aims to quantify irregular pulsations by the displacement and strain distribution of the intracranial aneurysm surface during the cardiac cycle using four-dimensional CT angiographic image data. Four-dimensional CT angiography was performed in 8 patients. The image data of a cardiac cycle was divided into approximately 20 phases, and irregular pulsations were detected in four intracranial aneurysms by visual observation, and then the displacement and strain of the intracranial aneurysm was quantified using coherent point drift and finite element method. The displacement and strain were compared between aneurysms with irregular and normal pulsations in two different ways (total and stepwise). The stepwise first principal strain was significantly higher in aneurysms with irregular than normal pulsations (0.20±0.01 vs 0.16±0.02, p=0.033). It was found that the irregular pulsations in intracranial aneurysms usually occur during the consecutive ascending or descending phase of volume changes during the cardiac cycle. In addition, no statistically significant difference was found in the aneurysm volume changes over the cardiac cycle between the two groups. Our method can successfully quantify the displacement and strain changes in the intracranial aneurysm during the cardiac cycle, which may be proven to be a useful tool to quantify intracranial aneurysm deformability and aid in aneurysm rupture risk assessment.
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Tomografia Computadorizada Quadridimensional , Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/fisiopatologia , Aneurisma Intracraniano/diagnóstico por imagem , Masculino , Feminino , Pessoa de Meia-Idade , Tomografia Computadorizada Quadridimensional/métodos , Idoso , Angiografia por Tomografia Computadorizada/métodos , Adulto , Fluxo PulsátilRESUMO
CagA is a significant oncogenic factor injected into host cells by Helicobacter pylori, which is divided into two subtypes: East Asian type (CagAE), characterized by the EPIYA-D motif, and western type (CagAW), harboring the EPIYA-C motif. CagAE has been reported to have higher carcinogenicity than CagAW, although the underlying reason is not fully understood. SHIP2 is an intracellular phosphatase that can be recruited by CagA to perturb the homeostasis of intracellular signaling pathways. In this study, we found that SHIP2 contributes to the higher oncogenicity of CagAE. Co-Immunoprecipitation and Pull-down assays showed that CagAE bind more SHIP2 than CagAW. Immunofluorescence staining showed that a higher amount of SHIP2 recruited by CagAE to the plasma membrane catalyzes the conversion of PI(3,4,5)P3 into PI(3,4)P2. This alteration causes higher activation of Akt signaling, which results in enhanced IL-8 secretion, migration, and invasion of the infected cells. SPR analysis showed that this stronger interaction between CagAE and SHIP2 stems from the higher affinity between the EPIYA-D motif of CagAE and the SH2 domain of SHIP2. Structural analysis revealed the crucial role of the Phe residue at the Y + 5 position in EPIYA-D. After mutating Phe of CagAE into Asp (the corresponding residue in the EPIYA-C motif) or Ala, the activation of downstream Akt signaling was reduced and the malignant transformation of infected cells was alleviated. These findings revealed that CagAE hijacks SHIP2 through its EPIYA-D motif to enhance its carcinogenicity, which provides a better understanding of the higher oncogenic risk of H. pylori CagAE.
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Motivos de Aminoácidos , Antígenos de Bactérias , Proteínas de Bactérias , Infecções por Helicobacter , Helicobacter pylori , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , Humanos , Antígenos de Bactérias/metabolismo , Antígenos de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Carcinogênese , População do Leste Asiático , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/patogenicidade , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/genética , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/metabolismo , Ligação Proteica , Transdução de SinaisRESUMO
BACKGROUND: Staphylococcus aureus, a commensal bacterium, colonizes the skin and mucous membranes of approximately 30% of the human population. Apart from conventional resistance mechanisms, one of the pathogenic features of S. aureus is its ability to survive in a biofilm state on both biotic and abiotic surfaces. Due to this characteristic, S. aureus is a major cause of human infections, with Methicillin-Resistant Staphylococcus aureus (MRSA) being a significant contributor to both community-acquired and hospital-acquired infections. RESULTS: Analyzing non-repetitive clinical isolates of MRSA collected from seven provinces and cities in China between 2014 and 2020, it was observed that 53.2% of the MRSA isolates exhibited varying degrees of ability to produce biofilm. The biofilm positivity rate was notably high in MRSA isolates from Guangdong, Jiangxi, and Hubei. The predominant MRSA strains collected in this study were of sequence types ST59, ST5, and ST239, with the biofilm-producing capability mainly distributed among moderate and weak biofilm producers within these ST types. Notably, certain sequence types, such as ST88, exhibited a high prevalence of strong biofilm-producing strains. The study found that SCCmec IV was the predominant type among biofilm-positive MRSA, followed by SCCmec II. Comparing strains with weak and strong biofilm production capabilities, the positive rates of the sdrD and sdrE were higher in strong biofilm producers. The genetic determinants ebp, icaA, icaB, icaC, icaD, icaR, and sdrE were associated with strong biofilm production in MRSA. Additionally, biofilm-negative MRSA isolates showed higher sensitivity rates to cefalotin (94.8%), daptomycin (94.5%), mupirocin (86.5%), teicoplanin (94.5%), fusidic acid (81.0%), and dalbavancin (94.5%) compared to biofilm-positive MRSA isolates. The biofilm positivity rate was consistently above 50% in all collected specimen types. CONCLUSIONS: MRSA strains with biofilm production capability warrant increased vigilance.
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Biofilmes , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/fisiologia , China/epidemiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Antibacterianos/farmacologia , Genes Bacterianos/genética , HumanosRESUMO
To investigate the effects of Luhong Yixin Granules on myocardial fibrosis in rats with heart failure and its possible mechanism, a total of 60 male Wistar rats were randomly divided into the control group, model group, and low-, medium-and high-dose Luhong Yixin Granules groups, with 12 rats in each group. Except for those in the control group, rats in the other groups were induced by intraperitoneal injection of doxorubicin(DOX) into a rat model. After the Luhong Yixin Granules were dissolved in the same amount of normal saline, they were given by gavage at low, medium and high doses(2.8, 5.6, 11.2 g·kg~(-1)·d~(-1)), and the control group and the model group were given the same amount of normal saline by gavage for 40 days. After the end of dosing, echocardiography was used to measure left ventricular ejection fraction(LVEF) and left ventricular fractional shortening(LVFS). Rat body weight(BW) and heart weight(HW) were calculated as HW/BW. Enzyme-linked immunosorbent assay was used to measure the levels of interleukin-6(IL-6), interleukin-17(IL-17), tumor necrosis factor-α(TNF-α), transforming growth factor-ß1(TGF-ß1), growth stimulation expressed gene 2 protein(ST2), N-terminal pro-B-type natriuretic peptide(NT-proBNP), galectin-3(Gal-3) and creatine kinase isoenzyme(CK-MB) in serum. Hematoxylin-eosin(HE) staining and Masson staining were used to observe the pathological morphology of myocardial tissue. Western blot and quantitative real-time polymerase chain reaction were used to detect the protein and mRNA expression levels of IL-6, IL-17, TNF-α, TGF-ß1, Smad3, Smad7, α-smooth muscle actin(α-SMA), and collagen â (COL-â ), respectively. RESULTS:: showed that compared with those in the control group, LVEF, LVFS, and HW/BW in the model group were decreased(P<0.05), and the levels of IL-6, IL-17, TNF-α, TGF-ß1, ST2, NT-proBNP, Gal-3, and CK-MB were increased(P<0.05). HE staining showed inflammatory changes in myocardial tissue; Masson staining showed decreases in the cross-sectional area and ventricular cavity area of the heart, and myocardial fibrosis of varying degrees(P<0.05). The protein and mRNA expression of IL-6, IL-17, TNF-α, TGF-ß1, Smad3, α-SMA, and COL-â were increased(P<0.05), and the protein and mRNA expression of Smad7 protein was decreased(P<0.01). Compared with those in the model group, LVEF, LVFS and HW/BW of the low-, medium-and high-dose Luhong Yixin Granules groups were increased(P<0.05), and the levels of IL-6, IL-17, TNF-α, TGF-ß1, ST2, NT-proBNP, Gal-3 and CK-MB were decreased(P<0.05). HE staining showed gradually reduced inflammatory changes of myocardial tissue, and Masson staining showed increased cross-sectional area and ventricular cavity area of the heart and decreased area of myocardial fibrosis(P<0.05). The protein and mRNA expression levels of IL-6, IL-17, TNF-α, TGF-ß1, Smad3, α-SMA, and COL-â were decreased(P<0.05), while the protein and mRNA expression levels of Smad7 were increased(P<0.05). Luhong Yixin Granules may be of great value in the treatment of heart failure by regulating the TGF-ß1/Smads signaling pathway, inhibiting the expression of inflammation-related proteins, reducing the deposition of extracellular matrix, and alleviating myocardial fibrosis.
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Medicamentos de Ervas Chinesas , Fibrose , Insuficiência Cardíaca , Miocárdio , Ratos Wistar , Transdução de Sinais , Proteínas Smad , Fator de Crescimento Transformador beta1 , Animais , Masculino , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/genética , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacologia , Ratos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Transdução de Sinais/efeitos dos fármacos , Miocárdio/patologia , Miocárdio/metabolismo , Proteínas Smad/metabolismo , Proteínas Smad/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , HumanosRESUMO
Electrochemical nitrate reduction (NO3RR) to ammonia production is regarded as one of the potential alternatives for replacing the Haber-Bosch technology for realizing artificial ammonia synthesis. In this study, a CuCo2O4/CuO-Ar heterostructure in the shape of dandelion nanospheres formed by nanoarrays has been successfully constructed, demonstrating excellent NO3RR performance. Experimental results indicate that Ar plasma etching of CuCo2O4/CuO-Ar significantly increases the content of oxygen vacancies compared to the sample of CuCo2O4/CuO-Air etched by air plasma, resulting in improved NO3RR performance. Density functional theory calculations further confirm that the existence of more oxygen vacancies effectively decreases the energy barrier of nitrate adsorption, which is due to the generation of more oxygen vacancies facilitating nitrate adsorption and weakening the N-O bonds of nitrate after plasma treatment. As a result, CuCo2O4/CuO-Ar exhibits a high NH3 yield of 0.55 mmol h-1 cm-2 and a Faraday efficiency of 95.07% at the optimal potential of -0.9 V (vs RHE) in a neutral medium. Importantly, CuCo2O4/CuO-Ar also showcases excellent electrocatalytic stability. This study presents new views on the design and structure regulation of NO3RR electrocatalysts and their potential applications in the future.
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OBJECTIVES: We aimed to develop and validate a radiomics nomogram based on dual-energy computed tomography (DECT) images and clinical features to classify the time since stroke (TSS), which could facilitate stroke decision-making. MATERIALS AND METHODS: This retrospective three-center study consecutively included 488 stroke patients who underwent DECT between August 2016 and August 2022. The eligible patients were divided into training, test, and validation cohorts according to the center. The patients were classified into two groups based on an estimated TSS threshold of ≤ 4.5 h. Virtual images optimized the visibility of early ischemic lesions with more CT attenuation. A total of 535 radiomics features were extracted from polyenergetic, iodine concentration, virtual monoenergetic, and non-contrast images reconstructed using DECT. Demographic factors were assessed to build a clinical model. A radiomics nomogram was a tool that the Rad score and clinical factors to classify the TSS using multivariate logistic regression analysis. Predictive performance was evaluated using receiver operating characteristic (ROC) analysis, and decision curve analysis (DCA) was used to compare the clinical utility and benefits of different models. RESULTS: Twelve features were used to build the radiomics model. The nomogram incorporating both clinical and radiomics features showed favorable predictive value for TSS. In the validation cohort, the nomogram showed a higher AUC than the radiomics-only and clinical-only models (AUC: 0.936 vs 0.905 vs 0.824). DCA demonstrated the clinical utility of the radiomics nomogram model. CONCLUSIONS: The DECT-based radiomics nomogram provides a promising approach to predicting the TSS of patients. CLINICAL RELEVANCE STATEMENT: The findings support the potential clinical use of DECT-based radiomics nomograms for predicting the TSS. KEY POINTS: Accurately determining the TSS onset is crucial in deciding a treatment approach. The radiomics-clinical nomogram showed the best performance for predicting the TSS. Using the developed model to identify patients at different times since stroke can facilitate individualized management.
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Nomogramas , Acidente Vascular Cerebral , Tomografia Computadorizada por Raios X , Humanos , Feminino , Masculino , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Pessoa de Meia-Idade , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Fatores de Tempo , Valor Preditivo dos Testes , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , RadiômicaRESUMO
OBJECTIVES: Aneurysm wall enhancement (AWE) on high-resolution contrast-enhanced vessel wall MRI (VWMRI) is an emerging biomarker for intracranial aneurysms (IAs) stability. Quantification methods of AWE in the literature, however, are variable. We aimed to determine the optimal post-contrast timing to quantify AWE in both saccular and fusiform IAs. MATERIALS AND METHODS: Consecutive patients with unruptured IAs were prospectively recruited. VWMRI was acquired on 1 pre-contrast and 4 consecutive post-contrast phases (each phase was 9 min). Signal intensity values of cerebrospinal fluid (CSF) and aneurysm wall on pre- and 4 post-contrast phases were measured to determine the aneurysm wall enhancement index (WEI). AWE was also qualitatively analyzed on post-contrast images using previous grading criteria. The dynamic changes of AWE grade and WEI were analyzed for both saccular and fusiform IAs. RESULTS: Thirty-four patients with 42 IAs (27 saccular IAs and 15 fusiform IAs) were included. The changes in AWE grade occurred in 8 (30%) saccular IAs and 6 (40%) in fusiform IAs during the 4 post-contrast phases. The WEI of fusiform IAs decreased 22.0% over time after contrast enhancement (p = 0.009), while the WEI of saccular IAs kept constant during the 4 post-contrast phases (p > 0.05). CONCLUSIONS: When performing quantitative analysis of AWE, acquiring post-contrast VWMRI immediately after contrast injection achieves the strongest AWE for fusiform IAs. While the AWE degree is stable for 36 min after contrast injection for saccular IAs. CLINICAL RELEVANCE STATEMENT: The standardization of imaging protocols and analysis methods for AWE will be helpful for imaging surveillance and further treatment decisions of patients with unruptured IAs. KEY POINTS: Imaging protocols and measurements of intracranial aneurysm wall enhancement are reported heterogeneously. Aneurysm wall enhancement for fusiform intracranial aneurysms (IAs) is strongest immediately post-contrast, and stable for 36 min for saccular IAs. Future multi-center studies should investigate aneurysm wall enhancement as an emerging marker of aneurysm growth and rupture.
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Polysaccharides and flavonoids have excellent antioxidant properties and tyrosinase inhibitory effects. In this paper, the antioxidant capacity of Inonotus sanghuang extract and its inhibition kinetics on mushroom tyrosinase were investigated to determine the preparation process of Inonotus sanghuang primary whitening gel. By conducting experimental studies on the effects of water extract and alcohol extract of Inonotus sanghuang on antioxidant capacity and tyrosinase activity, their inhibitory ability and types of inhibitory effects were determined. The single factor experiment was used to determine the preparation process of Sanghuang primary whitening gel. This study has proven that the extract of Inonotus sanghuang possesses antioxidant and tyrosinase inhibitory capabilities. It also identified the preparation process for the primary whitening gel of Inonotus sanghuang, thereby providing a theoretical and experimental basis for the development of whitening products utilising Inonotus sanghuang.
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Intracranial implants for diagnosis and treatment of brain diseases have been developed over the past few decades. However, the platform of conventional implantable devices still relies on invasive probes and bulky sensors in conjunction with large-area craniotomy and provides only limited biometric information. Here, an implantable multi-modal sensor array that can be injected through a small hole in the skull and inherently spread out for conformal contact with the cortical surface is reported. The injectable sensor array, composed of graphene multi-channel electrodes for neural recording and electrical stimulation and MoS2-based sensors for monitoring intracranial temperature and pressure, is designed based on a mesh structure whose elastic restoring force enables the contracted device to spread out. It is demonstrated that the sensor array injected into a rabbit's head can detect epileptic discharges on the surface of the cortex and mitigate it by electrical stimulation while monitoring both intracranial temperature and pressure. This method provides good potential for implanting a variety of functional devices via minimally invasive surgery.
Assuntos
Eletrodos Implantados , Grafite , Animais , Coelhos , Grafite/química , Estimulação Elétrica , Molibdênio/química , Dissulfetos/química , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Injeções , Pressão Intracraniana , Epilepsia/diagnósticoRESUMO
In a vast majority of bacteria, protozoa and plants, the methylerythritol phosphate (MEP) pathway is utilized for the synthesis of isopentenyl diphosphate (IDP) and dimethylallyl diphosphate (DMADP), which are precursors for isoprenoids. Isoprenoids, such as cholesterol and coenzyme Q, play a variety of crucial roles in physiological activities, including cell-membrane formation, protein degradation, cell apoptosis, and transcription regulation. In contrast, humans employ the mevalonate (MVA) pathway for the production of IDP and DMADP, rendering proteins in the MEP pathway appealing targets for antimicrobial agents. This pathway consists of seven consecutive enzymatic reactions, of which 4-diphosphocytidyl-2C-methyl-D-erythritol synthase (IspD) and 2C-methyl-D-erythritol 2,4-cyclodiphosphate synthase (IspF) catalyze the third and fifth steps, respectively. In this study, we characterized the enzymatic activities and protein structures of Helicobacter pylori IspDF and Acinetobacter baumannii IspD. Then, using the direct interaction-based thermal shift assay, we conducted a compound screening of an approved drug library and identified 27 hit compounds potentially binding to AbIspD. Among them, two natural products, rosmarinic acid and tanshinone IIA sodium sulfonate, exhibited inhibitory activities against HpIspDF and AbIspD, by competing with one of the substrates, MEP. Moreover, tanshinone IIA sodium sulfonate also demonstrated certain antibacterial effects against H. pylori. In summary, we identified two IspD inhibitors from approved ingredients, broadening the scope for antibiotic discovery targeting the MEP pathway.
Assuntos
Acinetobacter baumannii , Antibacterianos , Helicobacter pylori , Hemiterpenos , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/enzimologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/enzimologia , Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Produtos Biológicos/farmacologia , Produtos Biológicos/química , Compostos Organofosforados/farmacologia , Humanos , Transferases (Outros Grupos de Fosfato Substituídos)/antagonistas & inibidores , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismoRESUMO
BACKGROUND: SHP1 has been documented as a tumor suppressor and it was thought to play an antagonistic role in the pathogenesis of Helicobacter pylori infection. In this study, the exact mechanism of this antagonistic action was studied. MATERIALS AND METHODS: AGS, MGC803, and GES-1 cells were infected with H. pylori, intracellular distribution changes of SHP1 were first detected by immunofluorescence. SHP1 overexpression and knockdown were then constructed in these cells to investigate its antagonistic roles in H. pylori infection. Migration and invasion of infected cells were detected by transwell assay, secretion of IL-8 was examined via ELISA, the cells with hummingbird-like alteration were determined by microexamination, and activation of JAK2/STAT3, PI3K/Akt, and ERK pathways were detected by immunoblotting. Mice infection model was established and gastric pathological changes were evaluated. Finally, the SHP1 activator sorafenib was used to analyze the attenuating effect of SHP1 activation on H. pylori pathogenesis in vitro and in vivo. RESULTS: The sub-localization of SHP1 changed after H. pylori infection, specifically that the majority of the cytoplasmic SHP1 was transferred to the cell membrane. SHP1 inhibited H. pylori-induced activation of JAK2/STAT3 pathway, PI3K/Akt pathway, nuclear translocation of NF-κB, and then reduced EMT, migration, invasion, and IL-8 secretion. In addition, SHP1 inhibited the formation of CagA-SHP2 complex by dephosphorylating phosphorylated CagA, reduced ERK phosphorylation and the formation of CagA-dependent hummingbird-like cells. In the mice infection model, gastric pathological changes were observed and increased IL-8 secretion, indicators of cell proliferation and EMT progression were also detected. By activating SHP1 with sorafenib, a significant curative effect against H. pylori infection was obtained in vitro and in vivo. CONCLUSIONS: SHP1 plays an antagonistic role in H. pylori pathogenesis by inhibiting JAK2/STAT3 and PI3K/Akt pathways, NF-κB nuclear translocation, and CagA phosphorylation, thereby reducing cell EMT, migration, invasion, IL-8 secretion, and hummingbird-like changes.