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1.
Neural Netw ; 179: 106597, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39128275

RESUMEN

Convolutional Neural Networks (CNNs) have demonstrated outstanding performance in various domains, such as face recognition, object detection, and image segmentation. However, the lack of transparency and limited interpretability inherent in CNNs pose challenges in fields such as medical diagnosis, autonomous driving, finance, and military applications. Several studies have explored the interpretability of CNNs and proposed various post-hoc interpretable methods. The majority of these methods are feature-based, focusing on the influence of input variables on outputs. Few methods undertake the analysis of parameters in CNNs and their overall structure. To explore the structure of CNNs and intuitively comprehend the role of their internal parameters, we propose an Attribution Graph-based Interpretable method for CNNs (AGIC) which models the overall structure of CNNs as graphs and provides interpretability from global and local perspectives. The runtime parameters of CNNs and feature maps of each image sample are applied to construct attribution graphs (At-GCs), where the convolutional kernels are represented as nodes and the SHAP values between kernel outputs are assigned as edges. These At-GCs are then employed to pretrain a newly designed heterogeneous graph encoder based on Deep Graph Infomax (DGI). To comprehensively delve into the overall structure of CNNs, the pretrained encoder is used for two types of interpretable tasks: (1) a classifier is attached to the pretrained encoder for the classification of At-GCs, revealing the dependency of At-GC's topological characteristics on the image sample categories, and (2) a scoring aggregation (SA) network is constructed to assess the importance of each node in At-GCs, thus reflecting the relative importance of kernels in CNNs. The experimental results indicate that the topological characteristics of At-GC exhibit a dependency on the sample category used in its construction, which reveals that kernels in CNNs show distinct combined activation patterns for processing different image categories, meanwhile, the kernels that receive high scores from SA network are crucial for feature extraction, whereas low-scoring kernels can be pruned without affecting model performance, thereby enhancing the interpretability of CNNs.

2.
Sci Total Environ ; : 175451, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39134277

RESUMEN

Long-term trend forecast of chlorophyll-a concentration (Chla) holds significant implications for eutrophication management and pollution control planning on lakes, especially under the background of climate change. However, it is a challenging task due to the mixture of trend, seasonal and residual components in time series and the nonlinear relationships between Chla and the hydro-environmental factors. Here we developed a hybrid approach for long-term trend forecast of Chla in lakes, taking the Lake Taihu as an instantiation case, by the integration of Seasonal and Trend decomposition using Loess (STL), wavelet coherence, and Convolutional Neural Network with Bidirectional Long Short-Term Memory (CNN-BiLSTM). The results showed that long-term trends of Chla and the hydro-environmental factors could be effectively separated from the seasonal and residual terms by STL method, thereby enhancing the characterization of long-term variation. The resonance pattern and time lag between Chla and the hydro-environmental factors in the time-frequency domain were accurately identified by wavelet coherence. Chla responded quickly to variations in TP, but showed a time lag response to variation in WT in Lake Taihu. The forecasting method using multivariate and CNN-BiLSTM largely outperformed the other methods for Lake Taihu with regards to R2, RMSE, IOA and peak capture capability, owning to the combination of CNN for extracting local features and the integration of bidirectional propagation mechanism for the acquisition of higher-level features. The proposed hybrid deep learning approach offers an effective solution for the long-term trend forecast of algal blooms in eutrophic lakes and is capable of addressing the complex attributes of hydro-environmental data.

3.
Langmuir ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39110135

RESUMEN

Adsorption-desorption performance, electronic properties, and sensitivity of O-defective g-ZnO (ODZO) gas sensors for volatile organic compounds (VOCs) are calculated using density functional theory and nonequilibrium Green's formalism. The VOCs are CH2O, CH4, C2H4O, CH4O, and C2H6. The intrinsic g-ZnO (IZO) and ODZO exhibit strong adsorption capabilities for C2H4O and CH4O. The IZO (0.118 e) and ODZO (0.059 e), which act as electron donors, exhibit the highest charge transfer to CH2O, indicating a strong interaction. The VOCs adsorption on the IZO and ODZO systems maintain nonmagnetic semiconductor characteristics. Additionally, the introduction of an O-defect causes the adsorption energy and charge transfer amount of ODZO to show an overall decrease, indicating better desorption ability. Notably, the sensitivity results show that the ODZO gas sensors exhibit high sensitivity to CH2O (39.3%), C2H4O (29.0%), and CH4O (19.6%) at a voltage of 2.6 V, consistent with the adsorption-desorption performance and electronic properties.

4.
J Agric Food Chem ; 72(28): 15740-15754, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38970822

RESUMEN

Hepatic fibrosis is a compensatory response to chronic liver injury and inflammation, and dietary intervention is recommended as one of the fundamental prevention strategies. Raspberry ketone (RK) is an aromatic compound first isolated from raspberry and widely used to prepare food flavors. The current study investigated the hepatoprotection and potential mechanism of RK against hepatic fibrosis. In vitro, hepatic stellate cell (HSC) activation was stimulated with TGF-ß and cultured with RK, farnesoid X receptor (FXR), or peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) agonist or inhibitor, respectively. In vivo, C57BL/6 mice were injected intraperitoneally with thioacetamide (TAA) at 100/200 mg/kg from the first to the fifth week. Mice were intragastrically administrated with RK or Cur once a day from the second to the fifth week. In activated HSCs, RK inhibited extracellular matrix (ECM) accumulation, inflammation, and epithelial-mesenchymal transition (EMT) process. RK both activated FXR/PGC-1α and regulated their crosstalk, which were verified by their inhibitors and agonists. Deficiency of FXR or PGC-1α also attenuated the effect of RK on the reverse of activated HSCs. RK also decreased serum ALT/AST levels, liver histopathological change, ECM accumulation, inflammation, and EMT in mice caused by TAA. Double activation of FXR/PGC-1α might be the key targets for RK against hepatic fibrosis. Above all, these discoveries supported the potential of RK as a novel candidate for the dietary intervention of hepatic fibrosis.


Asunto(s)
Butanonas , Células Estrelladas Hepáticas , Cirrosis Hepática , Ratones Endogámicos C57BL , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Receptores Citoplasmáticos y Nucleares , Transducción de Señal , Animales , Humanos , Masculino , Ratones , Butanonas/farmacología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/efectos de los fármacos , Inflamación/metabolismo , Inflamación/tratamiento farmacológico , Cirrosis Hepática/metabolismo , Cirrosis Hepática/genética , Cirrosis Hepática/tratamiento farmacológico , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Receptores Citoplasmáticos y Nucleares/genética , Rubus/química , Transducción de Señal/efectos de los fármacos , Ratas
5.
Front Chem ; 12: 1425306, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39006489

RESUMEN

Stacking engineering is a popular method to tune the performance of two-dimensional materials for advanced applications. In this work, Jansu MoSSe and WSSe monolayers are constructed as a van der Waals (vdWs) heterostructure by different stacking configurations. Using first-principle calculations, all the relaxed stacking configurations of the MoSSe/WSSe heterostructure present semiconductor properties while the direct type-II band structure can be obtained. Importantly, the Z-scheme charge transfer mode also can be addressed by band alignment, which shows the MoSSe/WSSe heterostructure is an efficient potential photocatalyst for water splitting. In addition, the built-in electric field of the MoSSe/WSSe vdWs heterostructure can be enhanced by the S-Se interface due to further asymmetric structures, which also results in considerable charge transfer comparing with the MoSSe/WSSe vdWs heterostructure built by the S-S interface. Furthermore, the excellent optical performances of the MoSSe/WSSe heterostructure with different stacking configurations are obtained. Our results provide a theoretical guidance for the design and control of the two-dimensional heterostructure as photocatalysts through structural stacking.

6.
Phytother Res ; 38(8): 4009-4021, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38863408

RESUMEN

Environmental pollution, virus infection, allergens, and other factors may cause respiratory disease, which could be improved by dietary therapy. Allium species are common daily food seasoning and have high nutritional and medical value. Diallyl disulfide (DADS) is the major volatile oil compound of Allium species. The present study aims to explore the preventive effect and potential mechanism of DADS on pulmonary fibrosis. C57BL/6J mice were intratracheally injected with bleomycin (BLM) to establish pulmonary fibrosis and then administrated with DADS. Primary lung fibroblasts or A549 were stimulated with BLM, followed by DADS, farnesoid X receptor (FXR) agonist (GW4064), yes-associated protein 1 (YAP1) inhibitor (verteporfin), or silencing of FXR and YAP1. In BLM-stimulated mice, DADS significantly ameliorated histopathological changes and interleukin-1ß levels in bronchoalveolar lavage fluid. DADS decreased fibrosis markers, HIF-1α, inflammatory cytokines, and epithelial-mesenchymal transition in pulmonary mice and activated fibroblasts. DADS significantly enhanced FXR expression and inhibited YAP1 activation, which functions as GW4064 and verteporfin. A deficiency of FXR or YAP1 could result in the increase of these two protein expressions, respectively. DADS ameliorated extracellular matrix deposition, hypoxia, epithelial-mesenchymal transition, and inflammation in FXR or YAP1 knockdown A549. Taken together, targeting the crosstalk of FXR and YAP1 might be the potential mechanism for DADS against pulmonary fibrosis. DADS can serve as a potential candidate or dietary nutraceutical supplement for the treatment of pulmonary fibrosis.


Asunto(s)
Compuestos Alílicos , Disulfuros , Ratones Endogámicos C57BL , Fibrosis Pulmonar , Receptores Citoplasmáticos y Nucleares , Transducción de Señal , Proteínas Señalizadoras YAP , Animales , Fibrosis Pulmonar/tratamiento farmacológico , Fibrosis Pulmonar/inducido químicamente , Ratones , Disulfuros/farmacología , Humanos , Receptores Citoplasmáticos y Nucleares/metabolismo , Transducción de Señal/efectos de los fármacos , Compuestos Alílicos/farmacología , Células A549 , Masculino , Allium/química , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Bleomicina , Pulmón/efectos de los fármacos , Pulmón/patología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo
7.
Artículo en Inglés | MEDLINE | ID: mdl-38896523

RESUMEN

Graph neural networks have drawn increasing attention and achieved remarkable progress recently due to their potential applications for a large amount of irregular data. It is a natural way to represent protein as a graph. In this work, we focus on protein-protein binding sites prediction between the ligand and receptor proteins. Previous work just simply adopts graph convolution to learn residue representations of ligand and receptor proteins, then concatenates them and feeds the concatenated representation into a fully connected layer to make predictions, losing much of the information contained in complexes and failing to obtain an optimal prediction. In this paper, we present Intra-Inter Graph Representation Learning for protein-protein binding sites prediction (IIGRL). Specifically, for intra-graph learning, we maximize the mutual information between local node representation and global graph summary to encourage node representation to embody the global information of protein graph. Then we explore fusing two separate ligand and receptor graphs as a whole graph and learning affinities between their residues/nodes to propagate information to each other, which could effectively capture inter-protein information and further enhance the discrimination of residue pairs. Extensive experiments on multiple benchmarks demonstrate that the proposed IIGRL model outperforms state-of-the-art methods.

8.
Artículo en Inglés | MEDLINE | ID: mdl-38837929

RESUMEN

Mining discriminative graph topological information plays an important role in promoting graph representation ability. However, it suffers from two main issues: (1) the difficulty/complexity of computing global inter-class/intra-class scatters, commonly related to mean and covariance of graph samples, for discriminant learning; (2) the huge complexity and variety of graph topological structure that is rather challenging to robustly characterize. In this paper, we propose the Wasserstein Discriminant Dictionary Learning (WDDL) framework to achieve discriminant learning on graphs with robust graph topology modeling, and hence facilitate graph-based pattern analysis tasks. Considering the difficulty of calculating global inter-class/intra-class scatters, a reference set of graphs (aka graph dictionary) is first constructed by generating representative graph samples (aka graph keys) with expressive topological structure. Then, a Wasserstein Graph Representation (WGR) process is proposed to project input graphs into a succinct dictionary space through the graph dictionary lookup. To further achieve discriminant graph learning, a Wasserstein discriminant loss (WD-loss) is defined on the graph dictionary, in which the graph keys are optimizable, to make the intra-class keys more compact and inter-class keys more dispersed. Hence, the calculation of global Wasserstein metric (W-metric) centers can be bypassed. For sophisticated topology mining in the WGR process, a joint-Wasserstein graph embedding module is constructed to model both between-node and between-edge relationships across inputs and graph keys by encapsulating both the Wasserstein metric (between cross-graph nodes) and proposed novel Kron-Gromov-Wasserstein (KGW) metric (between cross-graph adjacencies). Specifically, the KGW-metric comprehensively characterizes the cross-graph connection patterns with the Kronecker operation, then adaptively captures those salient patterns through connection pooling. To evaluate the proposed framework, we study two graph-based pattern analysis problems, i.e. graph classification and cross-modal retrieval, with the graph dictionary flexibly adjusted to cater to these two tasks. Extensive experiments are conducted to comprehensively compare with existing advanced methods, as well as dissect the critical component of our proposed architecture. The experimental results validate the effectiveness of the WDDL framework.

9.
BMC Cardiovasc Disord ; 24(1): 269, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778265

RESUMEN

INTRODUCTION: Surgery remains the primary treatment modality for thymic carcinoma, with adjuvant radiotherapy being recommended to effectively mitigate local recurrence and metastasis rates subsequent to incomplete or complete resection. Chemoradiotherapy has the potential to induce coronary artery occlusion, thereby potentially impacting patients' long-term survival rates. The existing literature currently lacks comprehensive research on the lesion characteristics of coronary artery injury resulting from chemoradiotherapy. CASE PRESENTATION: The male patient, aged 55, was admitted to the hospital due to recurrent chest tightness and pain persisting for one week. Notably, the patient had previously undergone curative resection surgery for thymic carcinoma seven years ago. After the surgical procedure, the patient underwent a course of adjuvant chemotherapy comprising docetaxel and platinum. 11 months later, imaging examination diagnosed tumor recurrence, and concurrent chemoradiotherapy was administered at a total dose of 62 Gy/31F for planning gross target volume (PGTV) and 54 Gy/31F for planning target volume (PTV) with 2 cycles of paclitaxel and cisplatin. Re-admission of the patient occurred after a 7-year interval subsequent to the completion of concurrent chemoradiotherapy, leading to a subsequent diagnosis of acute non-ST segment elevation myocardial infarction. Following administration of antiplatelet, anticoagulant, and anti-myocardial ischemia therapy, coronary angiography revealed the presence of a bifurcation lesion at the distal end of the left main trunk. Intravascular ultrasound (IVUS) examination demonstrated significant negative remodeling of both the main trunk and its branches at the bifurcation site, characterized by minimal atherosclerotic plaque components. CONCLUSIONS: Chemoradiotherapy may induce damage to endothelial cells, resulting in an inflammatory response. Negative remodeling of blood vessels is likely to occur, primarily characterized by vasoconstriction but with less atherosclerotic plaque burden. Routine stent implantation in negatively remodeled areas may lead to vascular rupture, necessitating intravascular imaging examination.


Asunto(s)
Timoma , Neoplasias del Timo , Humanos , Masculino , Neoplasias del Timo/terapia , Neoplasias del Timo/diagnóstico por imagen , Persona de Mediana Edad , Resultado del Tratamiento , Factores de Tiempo , Timoma/terapia , Timoma/diagnóstico por imagen , Angiografía Coronaria , Lesiones del Sistema Vascular/etiología , Lesiones del Sistema Vascular/diagnóstico por imagen , Lesiones del Sistema Vascular/terapia , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/lesiones , Vasos Coronarios/efectos de los fármacos , Quimioradioterapia/efectos adversos
10.
Org Lett ; 26(20): 4229-4234, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38738828

RESUMEN

A copper-catalyzed [3 + 2] annulation of O-acyl oximes with 4-sulfonamidophenols is developed. The advantage of this method lies in the concurrent double activation of two substrates to form nucleophilic enamines and electrophilic quinone monoimines. The substituent on the α-carbon of O-acyl oxime determines two different reaction pathways, thereby leading to the selective generation of 5-sulfonamidoindoles and 2-amido-5-sulfonamidobenzofuran-3(2H)-ones.

11.
Pest Manag Sci ; 80(9): 4273-4285, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38625031

RESUMEN

BACKGROUND: To discover novel fungicide candidates, five series of novel norbornene hydrazide, bishydrazide, oxadiazole, carboxamide and acylthiourea derivatives (2a-2t, 3a-3f, 4a-4f, 5a-5f and 7a-7f) were designed, synthesized and assayed for their antifungal activity toward seven representative plant fungal pathogens. RESULTS: In the in vitro antifungal assay, some title norbornene derivatives presented good antifungal activity against Botryosphaeria dothidea, Sclerotinia sclerotiorum and Fusarium graminearum. Especially, compound 2b exhibited the best inhibitory activity toward B. dothidea with the median effective concentration (EC50) of 0.17 mg L-1, substantially stronger than those of the reference fungicides boscalid and carbendazim. The in vivo antifungal assay on apples revealed that 2b had significant curative and protective effects, both of which were superior to boscalid. In the preliminary antifungal mechanism study, 2b was able to injure the surface morphology of hyphae, destroy the cell membrane integrity and increase the intracellular reactive oxygen species (ROS) level of B. dothidea. In addition, 2b could considerably inhibit the laccase activity with the median inhibitory concentration (IC50) of 1.02 µM, much stronger than that of positive control cysteine (IC50 = 35.50 µM). The binding affinity and interaction mode of 2b with laccase were also confirmed by molecular docking. CONCLUSION: This study presented a promising lead compound for the study of novel laccase inhibitors as fungicidal agrochemicals, which demonstrate significant anti-B. dothidea activity and laccase inhibitory activity. © 2024 Society of Chemical Industry.


Asunto(s)
Ascomicetos , Fungicidas Industriales , Fusarium , Lacasa , Norbornanos , Fungicidas Industriales/farmacología , Fungicidas Industriales/síntesis química , Fungicidas Industriales/química , Fusarium/efectos de los fármacos , Norbornanos/farmacología , Norbornanos/química , Norbornanos/síntesis química , Ascomicetos/efectos de los fármacos , Lacasa/metabolismo , Simulación del Acoplamiento Molecular , Diseño de Fármacos , Relación Estructura-Actividad , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Antifúngicos/farmacología , Antifúngicos/síntesis química , Antifúngicos/química , Enfermedades de las Plantas/microbiología
12.
Chem Biodivers ; 21(6): e202400086, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38619074

RESUMEN

The endoperoxide group of artemisinins is universally accepted an essential group for their anti-cancer effects. In this study, a series of D-ring-contracted artemisinin derivatives were constructed by combining ring-contracted artemisinin core with fragments of functional heterocyclic molecules or classical CDK4/6 inhibitors to identify more efficacious breast cancer treatment agents. Twenty-six novel hybridized molecules were synthesized and characterized by HRMS, IR, 1H-NMR and 13C NMR. In antiproliferative activities and kinase inhibitory effects assays, we found that the antiproliferative effects of B01 were close to those of the positive control Palbociclib, with GI50 values of 4.87±0.23 µM and 9.97±1.44 µM towards T47D cells and MDA-MB-436 cells respectively. In addition, the results showed that B01 was the most potent compound against CDK6/cyclin D3 kinase, with an IC50 value of 0.135±0.041 µM, and its activity was approximately 1/3 of the positive control Palbociclib.


Asunto(s)
Antineoplásicos , Artemisininas , Neoplasias de la Mama , Proliferación Celular , Quinasa 4 Dependiente de la Ciclina , Quinasa 6 Dependiente de la Ciclina , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores de Proteínas Quinasas , Humanos , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/metabolismo , Artemisininas/farmacología , Artemisininas/química , Artemisininas/síntesis química , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 4 Dependiente de la Ciclina/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Proliferación Celular/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Relación Estructura-Actividad , Línea Celular Tumoral , Estructura Molecular , Femenino , Relación Dosis-Respuesta a Droga , Simulación del Acoplamiento Molecular
13.
Mol Biotechnol ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664305

RESUMEN

This study aimed to investigate the mechanisms of LACTB2 in colorectal cancer (CRC). Microarrays and sequencing data of CRC were acquired from UCSC Xena, GTEx, Gene Expression Omnibus, and TCGA. Pooled analysis of the mRNA expression of LACTB2 in CRC was performed using Stata software. The protein expression of LACTB2 in CRC tissues was evaluated by immunohistochemistry. The relationship between immune cell infiltration and LACTB2 expression was investigated using CIBERSORT. The potential signaling pathways and biological mechanisms of LACTB2 were explored using GSEA, KEGG, and GO. Subsequently, further screening of small molecular compounds with potential therapeutic effects on CRC was conducted through the HERB database, followed by molecular docking studies of these compounds with the LACTB2 protein. The integration and analysis of expression data obtained from 2294 CRC samples and 1286 noncancerous colorectal samples showed that LACTB2 was highly expressed in CRC. Immunohistochemistry performed on in-house tissue samples confirmed that LACTB2 protein expression was upregulated in CRC. CIBERSORT revealed lower B cell infiltration levels in the high LACTB2 expression group than in the low expression group. GO, KEGG, and GSEA analyses showed that LACTB2 expression and genes positively correlating with it were mainly related to DNA synthesis and repair, mitochondrial translational elongation and translational termination, phosphorylation, and mTORC1 signaling. Finally, molecular docking simulations confirmed the ability of quercitin to target and bind to LACTB2. This is the first study to demonstrate that LACTB2 is upregulated in CRC. LACTB2 promotes colorectal tumorigenesis and tumor progression.

14.
Angew Chem Int Ed Engl ; 63(13): e202315674, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38327006

RESUMEN

Sesquiterpene synthases (STPSs) catalyze carbocation-driven cyclization reactions that can generate structurally diverse hydrocarbons. The deprotonation-reprotonation process is widely used in STPSs to promote structural diversity, largely attributable to the distinct regio/stereoselective reprotonations. However, the molecular basis for reprotonation regioselectivity remains largely understudied. Herein, we analyzed two highly paralogous STPSs, Artabotrys hexapetalus (-)-cyperene synthase (AhCS) and ishwarane synthase (AhIS), which catalyze reactions that are distinct from the regioselective protonation of germacrene A (GA), resulting in distinct skeletons of 5/5/6 tricyclic (-)-cyperene and 6/6/5/3 tetracyclic ishwarane, respectively. Isotopic labeling experiments demonstrated that these protonations occur at C3 and C6 of GA in AhCS and AhIS, respectively. The cryo-electron microscopy-derived AhCS complex structure provided the structural basis for identifying different key active site residues that may govern their functional disparity. The structure-guided mutagenesis of these residues resulted in successful functional interconversion between AhCS and AhIS, thus targeting the three active site residues [L311-S419-C458]/[M311-V419-A458] that may act as a C3/C6 reprotonation switch for GA. These findings facilitate the rational design or directed evolution of STPSs with structurally diverse skeletons.


Asunto(s)
Transferasas Alquil y Aril , Sesquiterpenos , Microscopía por Crioelectrón , Sesquiterpenos/química , Catálisis , Dominio Catalítico , Transferasas Alquil y Aril/genética
15.
J Nat Med ; 78(2): 427-438, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38334900

RESUMEN

Angelica dahurica (A. dahurica) has a wide range of pharmacological effects, including analgesic, anti-inflammatory and hepatoprotective effects. In this study, we investigated the effect of A. dahurica extract (AD) and its effective component bergapten (BG) on hepatic fibrosis and potential mechanisms. Hepatic fibrosis was induced by intraperitoneal injection with carbon tetrachloride (CCl4) for 1 week, and mice were administrated with AD or BG by gavage for 1 week before CCl4 injection. Hepatic stellate cells (HSCs) were stimulated by transforming growth factor-ß (TGF-ß) and cultured with AD, BG, GW4064 (FXR agonist) or Guggulsterone (FXR inhibitor). In CCl4-induced mice, AD significantly decreased serum aminotransferase, reduced excess accumulation of extracellular matrix (ECM), inhibited caspase-1 and IL-1ß, and increased FXR expressions. In activated HSCs, AD suppressed the expressions of α-SMA, collagen I, and TIMP-1/MMP-13 ratio and inflammatory factors, functioning as FXR agonist. In CCl4-induced mice, BG significantly improved serum transaminase and histopathological changes, reduced ECM excessive deposition, inflammatory response, and activated FXR expression. BG increased FXR expression and inhibited α-SMA and IL-1ß expressions in activated HSCs, functioning as GW4064. FXR deficiency significantly attenuated the decreasing effect of BG on α-SMA and IL-1ß expressions in LX-2 cells. In conclusion, AD could regulate hepatic fibrosis by regulating ECM excessive deposition and inflammation. Activating FXR signaling by BG might be the potential mechanism of AD against hepatic fibrosis.


Asunto(s)
Cirrosis Hepática , Transducción de Señal , Ratones , Animales , 5-Metoxipsoraleno/efectos adversos , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/tratamiento farmacológico , Células Estrelladas Hepáticas , Factor de Crecimiento Transformador beta/farmacología , Hígado
16.
Small Methods ; 8(7): e2301236, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38351479

RESUMEN

Deoxyribonucleic acid (DNA)-based hydrogels are emerging as promising functional materials for biomedical applications. However, the shelf-time of DNA hydrogels in biological media is severely shortened by nucleases, which limit the application of DNA hydrogels. Herein, a DNA hydrogel with long shelf-time is reported for 3D cell culture. Poly-(L-lysine) (PLL) is introduced as both a cross-linker and a protectant. The electrostatic interaction between PLL and DNA drove the formation of hydrogel. PLL coating on DNA increased the steric hindrance between DNA and nucleases, thus weakening the digestion of nucleases toward phosphodiester bond. As a result, the shelf-time of DNA/PLL hydrogel for 3D cell culture is extended from generally 1 day to longer than 15 days, which has not been achieved previously. Notably, poly-AS1411-aptamers are integrated to DNA/PLL hydrogels for anchoring U87 cells, and the cell encapsulation efficiency of the DNA/PLL hydrogels with aptamer is 4-time higher than that of the hydrogels without aptamer. DNA/PLL hydrogel provided a favorable microenvironment to support the proliferation of cells, which formed cell spheroid in 15 days. This protective coating strategy solves the long-standing problem on the shelf-time of DNA hydrogel, and is envisioned to promote the development of DNA hydrogel in more biomedical applications.


Asunto(s)
Técnicas de Cultivo Tridimensional de Células , ADN , Hidrogeles , Polilisina , Polilisina/química , Hidrogeles/química , Humanos , ADN/química , Técnicas de Cultivo Tridimensional de Células/métodos , Línea Celular Tumoral , Aptámeros de Nucleótidos/química , Proliferación Celular/efectos de los fármacos
17.
Sensors (Basel) ; 24(3)2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38339478

RESUMEN

The gas sensitivity of the W defect in WS2 (VW/WS2) to five toxic gases-HCHO, CH4, CH3HO, CH3OH, and CH3CH3-has been examined in this article. These five gases were adsorbed on the VW/WS2 surface, and the band, density of state (DOS), charge density difference (CDD), work function (W), current-voltage (I-V) characteristic, and sensitivity of adsorption systems were determined. Interestingly, for HCHO-VW/WS2, the energy level contribution of HCHO is closer to the Fermi level, the charge transfer (B) is the largest (0.104 e), the increase in W is more obvious than other adsorption systems, the slope of the I-V characteristic changes more obviously, and the calculated sensitivity is the highest. To sum up, VW/WS2 is more sensitive to HCHO. In conclusion, VW/WS2 has a great deal of promise for producing HCHO chemical sensors due to its high sensitivity and selectivity for HCHO, which can aid in the precise and efficient detection of toxic gases.

18.
Int Wound J ; 21(2): e14594, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38379217

RESUMEN

To evaluate the efficacy of cognitive behavioural therapy (CBT) as a psychological intervention for elderly patients with extensive burns, focusing on its impact on emotional well-being, self-efficacy and quality of life. A prospective, randomized study involving 200 elderly burn patients was conducted from November 2021 to January 2023. The patients were randomly assigned to receive either standard care (control group) or burn care based on cognitive behavioural therapy (CBT-B) (study group), with 100 patients in each group. Outcome measures included the Visual Analog Scale (VAS) for pain assessment, 36-item Short Form Survey (SF-36) for quality of life, General Self-Efficacy Scale (GSES) and Rosenberg Self-Esteem Scale (RSES). The study revealed that CBT-based intervention significantly reduced anxiety and depression scores compared with standard care (p < 0.05). Additionally, patients in the CBT group exhibited improved self-efficacy, self-esteem and quality of life (p < 0.05). CBT proves to be a valuable intervention for elderly burn patients, effectively addressing emotional distress and enhancing their psychological well-being. By modifying negative cognitive patterns, providing coping mechanisms and fostering problem-solving skills, CBT-based care contributes to a more positive recovery experience and improved quality of life.


Asunto(s)
Terapia Cognitivo-Conductual , Calidad de Vida , Humanos , Anciano , Estudios Prospectivos , Intervención Psicosocial , Ansiedad/terapia
19.
Phys Chem Chem Phys ; 26(6): 5569-5578, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38284264

RESUMEN

The g-ZnO/Si9C15 heterojunction is designed, and its stability, electronic properties and photo-electro catalytic properties, and the impact of biaxial strain on the electronic and photocatalytic properties are investigated. The g-ZnO/Si9C15 heterojunction has a staggered (type-II) band structure (band gap is 1.770 eV), following the S-scheme mechanism. A high electron mobility of 5.113 × 103 cm2 V-1 s-1 and hole mobility of 3.324 × 104 cm2 V-1 s-1 are obtained in the zigzag and armchair directions, respectively. Suitable oxidation and reduction potentials are obtained such that photocatalytic water decomposition can occur at pH = 0-14, and the corrected solar to hydrogen (STH) efficiency is up to 35.4%. The absorption of visible light is enhanced, and the power conversion efficiency (PCE) is 15.1%. The electro-catalytic hydrogen evolution reaction (HER) is more likely to occur at the Si9C15 interface with a low over-voltage of 0.190 V. Under biaxial strain, due to the controllable band structure, the corrected STH efficiency and PCE increase to 42.7% and 16.7%, respectively. The heterojunction shows potential value in the field of high-efficiency solar devices and catalytic materials for water splitting.

20.
Biomed Pharmacother ; 171: 116167, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38262152

RESUMEN

Atopic dermatitis (AD) is a prevalent chronic inflammatory skin disease. The Janus kinase (JAK) has been identified as a target in AD, as it regulates specific inflammatory genes and adaptive immune responses. However, the efficacy of topically applied JAK inhibitors in AD is limited due to the unique structure of skin. We synthesized JAK1/JAK2 degraders (JAPT) based on protein degradation targeting chimeras (PROTACs) and prepared them into topical preparations. JAPT exploited the E3 ligase to mediate ubiquitination and degradation of JAK1/JAK2, offering a promising AD therapeutic approach with low frequency and dosage. In vitro investigations demonstrated that JAPT effectively inhibited the release of pro-inflammatory cytokines and reduced inflammation by promoting the degradation of JAK. In vivo studies further confirmed the efficacy of JAPT in degrading JAK1/JAK2, leading to a significant suppression of type I, II, and III adaptive immunity. Additionally, JAPT demonstrated a remarkable reduction in AD severity, as evidenced by improved skin lesion clearance and AD severity scores (SCORAD). Our study revealed the therapeutic potential of JAPT, surpassing conventional JAK inhibitors in the treatment of AD, which suggested that JAPT could be a promising topically applied anti-AD drug targeting the JAK-STAT signaling pathway.


Asunto(s)
Dermatitis Atópica , Inhibidores de las Cinasas Janus , Enfermedades de la Piel , Humanos , Dermatitis Atópica/tratamiento farmacológico , Inhibidores de las Cinasas Janus/uso terapéutico , Piel , Inflamación/tratamiento farmacológico , Quinasas Janus/metabolismo , Enfermedades de la Piel/metabolismo , Janus Quinasa 1/metabolismo , Janus Quinasa 2/metabolismo
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