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1.
J Magn Reson Imaging ; 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38243392

RESUMEN

BACKGROUND: The alternation of brain white matter (WM) network has been studied in adult spinal cord injury (SCI) patients. However, the WM network alterations in pediatric SCI patients remain unclear. PURPOSE: To evaluate WM network changes and their functional impact in children with thoracolumbar SCI (TSCI). STUDY TYPE: Prospective. SUBJECTS: Thirty-five pediatric patients with TSCI (8.94 ± 1.86 years, 8/27 males/females) and 34 age- and gender-matched healthy controls (HCs) participated in this study. FIELD STRENGTH/SEQUENCE: 3.0 T/DTI imaging using spin-echo echo-planar and T1-weighted imaging using 3D T1-weighted magnetization-prepared rapid gradient-echo sequence. ASSESSMENT: Pediatric SCI patients were evaluated for motor and sensory scores, injury level, time since injury, and age at injury. The WM network was constructed using a continuous tracing method, resulting in a 90 × 90 matrix. The global and regional metrics were obtained to investigate the alterations of the WM structural network. topology. STATISTICAL TESTS: Two-sample independent t-tests, chi-squared test, Mann-Whitney U-test, and Spearman correlation. Statistical significance was set at P < 0.05. RESULTS: Compared with HCs, pediatric TSCI patients displayed decreased shortest path length (Lp = 1.080 ± 0.130) and normalized Lp (λ = 5.020 ± 0.363), and increased global efficiency (Eg = 0.200 ± 0.015). Notably, these patients also demonstrated heightened regional properties in the orbitofrontal cortex, limbic system, default mode network, and several audio-visual-related regions. Moreover, the λ and Lp values negatively correlated with sensory scores. Conversely, nodal efficiency values in the right calcarine fissure and surrounding cortex positively correlated with sensory scores. The age at injury positively correlated with node degree in the left parahippocampal gyrus and nodal efficiency in the right posterior cingulate gyrus. DATA CONCLUSION: Reorganization of the WM networks in pediatric SCI patients is indicated by increased global and nodal efficiency, which may provide promising neuroimaging biomarkers for functional assessment of pediatric SCI. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 5.

2.
J Org Chem ; 89(7): 4774-4783, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38506335

RESUMEN

A facile and efficient copper-catalyzed domino-double annulation strategy was developed from easily accessible o-aminobenzamides and 2-iodoisothiocyanates, which affords a direct pathway for the synthesis of tetracyclic fused 12H-benzo[4,5]thiazolo[2,3-b]quinazolin-12-ones in moderate to good yields without the addition of ligands, bases, and external oxidants. The reaction involves a C-N bond cleavage and the formation of a C-N/C-S bond in one step with the advantages of using an inexpensive copper catalyst and easy operation. Mechanistic studies suggest that this transformation proceeds via intermolecular condensation of o-aminobenzamides with 2-iodoisothiocyanates, followed by an intramolecular Ullmann-type cross-coupling cyclization reaction.

3.
J Org Chem ; 89(7): 4579-4594, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38506748

RESUMEN

A palladium-catalyzed intermolecular [2 + 2 + 2] oxidative coupling-annulation of terminal alkenes and alkynes using copper(II) as the oxidant has been developed through direct C-C bond formation. These reactions provide effective access to multiaryl-substituted benzenes with high regioselectivity in the absence of any ligands. The features of this protocol are broad substrate scope, and high atom and step economy. The aggregation-induced emission properties of selected products were further investigated. These synthesized multiaryl-substituted benzenes may be worth exploring for further applications in the fields of advanced functional materials or drugs.

4.
Spinal Cord ; 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824252

RESUMEN

STUDY DESIGN: Cross-sectional study. OBJECTIVES: To study the relationship between the structural changes in the cervical spinal cord (C2/3 level) and the sensorimotor function of children with traumatic thoracolumbar spinal cord injury (TLSCI) and to discover objective imaging biomarkers to evaluate its functional status. SETTING: Xuanwu Hospital, Capital Medical University, China; Beijing Key Laboratory of Magnetic Resonance Imaging and Brain Informatics, China. METHODS: 30 children (age range 5-13 years) with TLSCI and 11 typically developing (TD) children (age range 6-12 years) were recruited in this study. Based on whether there is preserved motor function below the neurological level of injury (NLI), the children with TLSCI are divided into the AIS A/B group (motor complete) and the AIS C/D group (motor incomplete). A Siemens Verio 3.0 T MR scanner was used to acquire 3D high-resolution anatomic scans covering the head and upper cervical spinal cord. Morphologic parameters of the spinal cord at the C2/3 level, including cross-sectional area (CSA), anterior-posterior width (APW), and left-right width (LRW) were obtained using the spinal cord toolbox (SCT; https://www.nitrc.org/projects/sct ). Correlation analyses were performed to compare the morphologic spinal cord parameters and clinical scores determined by the International Standard for Neurological Classification of Spinal Cord Injuries (ISNCSCI) examination. RESULTS: CSA and LRW in the AIS A/B group were significantly lower than those in the TD group and the AIS C/D group. LRW was the most sensitive imaging biomarker to differentiate the AIS A/B group from the AIS C/D group. Both CSA and APW were positively correlated with ISNCSCI sensory scores. CONCLUSIONS: Quantitative measurement of the morphologic spinal cord parameters of the cervical spinal cord can be used as an objective imaging biomarker to evaluate the neurological function of children with TLSCI. Cervical spinal cord atrophy in children after TLSCI was correlated with clinical grading; CSA and APW can reflect sensory function. Meanwhile, LRW has the potential to be an objective imaging biomarker for evaluating motor function preservation.

5.
J Magn Reson Imaging ; 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37800893

RESUMEN

BACKGROUND: Injury to the spinal cord of children may cause potential brain reorganizations, affecting their rehabilitation. However, the specific functional alterations of children after complete spinal cord injury (CSCI) remain unclear. PURPOSE: To explore the specific functional changes in local brain and the relationship with clinical characteristics in pediatric CSCI patients, clarifying the impact of CSCI on brain function in developing children. STUDY TYPE: Prospective. SUBJECTS: Thirty pediatric CSCI patients (7.83 ± 1.206 years) and 30 age-, gender-matched healthy children as controls (HCs) (8.77 ± 2.079 years). FIELD STRENGTH/SEQUENCE: 3.0 T/Resting-state functional MRI (rs-fMRI) using echo-planar-imaging (EPI) sequence. ASSESSMENT: Amplitude of low-frequency fluctuation (ALFF), fractional ALFF (fALFF), and regional homogeneity (ReHo) were used to characterize regional neural function. STATISTICAL TESTS: Two-sample t-tests were used to compare the ALFF, fALFF, ReHo values of the brain between pediatric CSCI and HCs (voxel-level FWE correction, P < 0.05). Spearman correlation analyses were performed to analyze the associations between the ALFF, fALFF, ReHo values in altered regions and the injury duration, sensory motor scores of pediatric CSCI patients (P < 0.05). Then receiver operating characteristic (ROC) analysis was conducted to identify possible sensitive imaging indicators for clinical therapy. RESULTS: Compared with HCs, pediatric CSCI showed significantly decreased ALFF in the right postcentral gyrus (S1), orbitofrontal cortex, and left superior temporal gyrus (STG), increased ALFF in bilateral caudate nucleus, thalamus, middle cingulate gyrus, and cerebellar lobules IV-VI, and increased ReHo in left cerebellum Crus II and Brodmann area 21. The ALFF value in the right S1 negatively correlated with the pinprick and light touch sensory scores of pediatric CSCI. When the left STG was used as an imaging biomarker for pediatric CSCI, it achieved the highest area under the curve of 0.989. CONCLUSIONS: These findings may provide potential neural mechanisms for sensory motor and cognitive-emotional deficits in children after CSCI. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 5.

6.
J Org Chem ; 88(4): 2190-2206, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36724037

RESUMEN

A copper-promoted aerobic oxidative [3+2] cycloaddition reaction for the synthesis of various substituted pyrazoles from N,N-disubstituted hydrazines with alkynoates in the presence of bases is developed. This work involves a direct C(sp3)-H functionalization and the formation of new C-C/C-N bonds. In this strategy, inexpensive and easily available Cu2O serves as the promoter and air acts as the green oxidant. The reaction exhibits the advantages of high atom and step economy, high regioselectivity, and easy operation.

7.
J Org Chem ; 88(1): 272-284, 2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36521048

RESUMEN

A facile and efficient catalyst-/metal-/oxidant-free DBU-promoted deaminative thiolation reaction of 1H-benzo[d]imidazol-2-amines and benzo[d]oxazol-2-amines has been developed at room temperature conditions in a one-pot protocol. This practical three-component strategy represents a novel and environmentally friendly reaction pathway toward the straightforward synthesis of various 2-thio-1H-benzo[d]imidazoles and 2-thiobenzo[d]oxazoles using carbon disulfide as a sulfur source through C-N bond cleavage and C-S bond formation process. Different types of 1H-benzo[d]imidazol-2-amines, benzo[d]oxazol-2-amines, and organic bromides are suitable substrates. The gram-scale and late-stage modification experiments provide the potential applications based on this methodology in the field of organic and medicinal chemistry.

8.
J Periodontal Res ; 58(4): 841-851, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37243354

RESUMEN

BACKGROUND AND OBJECTIVE: Periodontitis is a multifactorial inflammatory disease that leads to the destruction of supporting structures of the teeth. DNA damage-inducible transcript 3 (DDIT3) plays crucial roles in cell survival and differentiation. DDIT3 regulates bone mass and osteoclastogenesis in femur. However, the role of DDIT3 in periodontitis has not been elucidated. This research aimed to explore the role and mechanisms of DDIT3 in periodontitis. METHODS: DDIT3 gene knockout (KO) mice were generated using a CRISPR/Cas9 system. Experimental periodontitis models were established to explore the role of DDIT3 in periodontitis. The expression of DDIT3 in periodontal tissues was detected by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC). The alveolar bone phenotypes were observed by micro-CT and stereomicroscopy. The inflammation levels and osteoclast activity were examined by histological staining, immunostaining, and qRT-PCR. Bone marrow-derived macrophages (BMMs) were isolated to confirm the effects of DDIT3 on osteoclast formation and function in vitro. RESULTS: The increased expression of DDIT3 in murine inflamed periodontal tissues was detected. DDIT3 knockout aggravated alveolar bone loss and enhanced expression levels of inflammatory cytokines in murine periodontitis models. Increased osteoclast formation and higher expression levels of osteoclast-specific markers were observed in the inflamed periodontal tissues of KO mice. In vitro, DDIT3 deficiency promoted the formation of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated osteoclasts and the bone resorption activity of mature osteoclasts. CONCLUSIONS: Our results demonstrate that DDIT3 deletion aggravated alveolar bone loss in experimental periodontitis through enhanced inflammatory reactions and osteoclastogenesis. The anti-inflammation and the inhibition of bone loss by DDIT3 in murine periodontitis provides a potential novel therapeutic strategy for periodontitis.


Asunto(s)
Pérdida de Hueso Alveolar , Resorción Ósea , Periodontitis , Animales , Ratones , Pérdida de Hueso Alveolar/patología , Daño del ADN , Inflamación/patología , Osteoclastos/metabolismo , Periodontitis/tratamiento farmacológico , Ligando RANK/metabolismo
9.
J Cell Physiol ; 235(5): 4698-4708, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31642068

RESUMEN

Yes-associated protein 1 (YAP1), the core downstream effector of the Hippo signaling cascade, was involved in the regulation of osteoblast and osteoclast differentiation and in bone metabolism. However, the regulatory effects and mechanisms of YAP1 on bone-remodeling molecules in osteoblasts under inflammation remain unknown. In this study, YAP1 expression level was downregulated after treatment with inflammatory cytokine tumor necrosis factor-α (TNF-α) in MC3T3-E1 cells. The key osteoclastogenic molecules induced by TNF-α, namely, interleukin-6 and receptor activator of nuclear factor-κB (NF-κB) ligand, were suppressed after lentivirus-induced YAP1 overexpression, which dramatically increased the expression level of osteoprotegerin. Conversely, the expression levels of the above factors showed opposite trends in the YAP1 small interfering RNA and YAP1 inhibitor (verteporfin) group. Mechanistically, YAP1 attenuated the TNF-α-induced activation of the NF-κB signaling pathway as revealed by the reduced expression of phosphorylated-p65 and NF-κB reporter activity and the nuclear translocation of p65. Moreover, the expression level of YAP1 suppressed by TNF-α was reversed by berberine in concentration-dependent manner. Taken together, our study suggests that YAP1 plays a critical role in the regulation of bone metabolism and is a potential therapeutic target for treating inflammatory bone resorption.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Remodelación Ósea/efectos de los fármacos , Resorción Ósea/metabolismo , Proteínas de Ciclo Celular/metabolismo , FN-kappa B/metabolismo , Osteoblastos/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Células 3T3 , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Resorción Ósea/genética , Resorción Ósea/fisiopatología , Proteínas de Ciclo Celular/genética , Interleucina-6/genética , Interleucina-6/metabolismo , Ratones , FN-kappa B/genética , Osteoblastos/metabolismo , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Ligando RANK/genética , Ligando RANK/metabolismo , Transducción de Señal , Proteínas Señalizadoras YAP
10.
Mol Cell Biochem ; 474(1-2): 209-218, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32748312

RESUMEN

Local injection of tumor necrosis factor-alpha (TNF-α) at bone fracture sites during the early stage of the inflammatory response is reported to improve fracture repair in a murine model. However, the underlying mechanism is unclear. Endochondral bone formation, a process that is highly related to fracture repair, requires a certain amount of chondrocyte hypertrophy. This study aimed to investigate the effect of TNF-α on the differentiation of murine chondrogenic ATDC5 cells and the underlying mechanism. In this study, improved chondrogenic differentiation of ATDC5 cells was achieved by brief TNF-α stimulation. Moreover, the expression of Yes-associated protein 1 (YAP1) was suppressed after brief TNF-α stimulation. The expressions of inflammatory mediators and chondrogenic and hypertrophic-associated genes in ATDC5 cells triggered by TNF-α were suppressed in the YAP1 overexpression group but enhanced in the YAP1 knockdown group. Mechanistically, TNF-α-induced activation of the 5' AMP-activated protein kinase (AMPK) signaling pathway was regulated by YAP1, as revealed by the phosphorylated-AMPK/AMPK change ratios in the YAP1 overexpression and knockdown groups, respectively. Moreover, the potential for TNF-α to enhance chondrogenic differentiation could be partially reversed with an AMPK inhibitor. Taken together, we demonstrate, for the first time, that YAP1 modulates the ability of TNF-α to enhance chondrocyte differentiation partly through AMPK signaling.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Diferenciación Celular , Condrocitos/citología , Condrogénesis , Inflamación/tratamiento farmacológico , Factores de Transcripción/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Animales , Proteínas de Ciclo Celular/metabolismo , Línea Celular , Proliferación Celular , Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Humanos , Inflamación/inmunología , Inflamación/metabolismo , Ratones , Transducción de Señal , Proteínas Señalizadoras YAP
11.
J Cell Physiol ; 234(7): 11602-11609, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30488444

RESUMEN

DDIT3 is of great importance in endoplasmic reticulum stress and is involved in many inflammatory diseases and mineralization processes. The cementum protects teeth from periodontitis and provides attachment for Sharpey's fibers of the periodontal ligament. However, the effect of DDIT3 on cementoblast differentiation remains largely unknown. In this study, we found that DDIT3 was suppressed during cementoblast differentiation. Knockdown of DDIT3 increased the messenger RNA (mRNA) and protein levels of several key osteogenic markers in vitro, including alkaline phosphatase, runt-related transcription factor 2, and osteocalcin (OCN). In addition, isocitrate dehydrogenase 1 (IDH1) was increased during cementoblast differentiation, and knockdown of DDIT3 increased the protein and mRNA levels of IDH1. Furthermore, inhibition of IDH1 could partially reduce the effect of DDIT3 on cementoblast differentiation. The DDIT3 knockdown activated nuclear factor-κB (NF-κB) transcriptional activity and upregulated the expression of p-p65 and p-IκBα. The increased osteogenic differentiation ability and IDH1 expression, as induced by the DDIT3 knockdown, could be partially turned over by the addition of NF-κB inhibitor BAY 11-7082. Overall, our data clarified that DDIT3 suppresses cementoblast differentiation through IDH1, via the NF-κB pathway.


Asunto(s)
Cemento Dental/metabolismo , Isocitrato Deshidrogenasa/metabolismo , FN-kappa B/metabolismo , Factor de Transcripción CHOP/metabolismo , Animales , Diferenciación Celular , Línea Celular , Regulación de la Expresión Génica/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Humanos , Isocitrato Deshidrogenasa/genética , Ratones , FN-kappa B/genética , Nitrilos/farmacología , Sulfonas/farmacología , Factor de Transcripción CHOP/genética
12.
J Cell Physiol ; 234(8): 14007-14018, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30618072

RESUMEN

Yes-associated protein 1 (YAP1) transcriptional coactivator has recently been identified to regulate skeletal lineage cell differentiation and bone development. However, the role and molecular mechanisms of YAP1 in the regulation of osteoblastic differentiation remains to be elucidated. In this study, we demonstrated that YAP1 expression was increased during osteogenic differentiation of rat bone mesenchymal stem cells and MC3T3-E1. YAP1 overexpression MC3T3-E1 showed increased expression of osteogenesis markers, such as runt-related transcription factor 2, osteocalcin, and osteopontin, as well as alkaline phosphatase and alizarin red staining. Conversely, YAP1 knockdown significantly suppressed MC3T3-E1 osteoblastic differentiation. Mechanistically, we found that YAP1 overexpression upregulated the mRNA and protein expression of the inhibitor of differentiation/DNA binding 1 (ID1), which was contrary to the results of YAP1-knockdown group. Moreover, the early osteogenic differentiation of MC3T3-E1 cells was enhanced by ID1 overexpression. Furthermore, transient transfection with exogenous ID1 overexpression plasmid completely recaptured the decreased effects of YAP1 knockdown on MC3T3-E1 cell differentiation. In addition, ß-catenin and AMP-activated protein kinase signaling pathways participated in YAP1 regulation processes. Taken together, our study suggests that YAP1 is a crucial modulator of osteoblast differentiation in vitro, and provides insight into the mechanism by which YAP1 regulates osteoblast differentiation.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas de Ciclo Celular/metabolismo , Diferenciación Celular , Osteoblastos/citología , Osteoblastos/metabolismo , Osteogénesis , Adenilato Quinasa/metabolismo , Animales , Diferenciación Celular/genética , Línea Celular , Proliferación Celular , Regulación hacia Abajo/genética , Proteína 1 Inhibidora de la Diferenciación/metabolismo , Células Madre Mesenquimatosas/metabolismo , Ratones , Modelos Biológicos , Osteogénesis/genética , Ratas Sprague-Dawley , Transducción de Señal , Transcripción Genética , Regulación hacia Arriba/genética , Proteínas Señalizadoras YAP , beta Catenina/metabolismo
13.
J Cell Physiol ; 233(3): 2213-2224, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28688217

RESUMEN

Yes-associated protein 1 (YAP1) transcriptional coactivator is a mediator of mechanosensitive signaling. Cementum, which covers the tooth root surface, continuously senses external mechanical stimulation. Cementoblasts are responsible for the mineralization and maturation of the cementum. However, the effect of YAP1 on cementoblast differentiation remains largely unknown. In this study, we initially demonstrated that YAP1 overexpression enhanced the mineralization ability of cementoblasts. YAP1 upregulated the mRNA and protein expression of several cementogenesis markers, such as alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2), osteocalcin (OCN), and dentin matrix acidic phosphoprotein 1 (DMP1). The YAP1 overexpression group showed higher intensities of ALP and Alizarin red stain than the YAP1-knockdown group. Unexpectedly, a sharp increase in the expression of dentin sialophosphoprotein (DSPP) was induced by the overexpression of YAP1. Knockdown of YAP1 suppressed DSPP transcriptional activity. YAP1 overexpression activated Smad-dependent BMP signaling and slightly inhibited Erk1/2 signaling pathway activity. Treatment with specific BMP antagonist (LDN193189) prevented the upregulation of the mRNA levels of ALP, RUNX2, and OCN, as well as intensity of ALP-stained and mineralized nodules in cementoblasts. The Erk1/2 signaling pathway inhibitor (PD 98,059) upregulated these cementogenesis markers. Thus, our study suggested that YAP1 enhanced cementoblast mineralization in vitro. YAP1 exerted its effect on the cementoblast partly by regulating the Smad-dependent BMP and Erk1/2 signaling pathways.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteína Morfogenética Ósea 1/metabolismo , Cementogénesis/fisiología , Cemento Dental/citología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Fosfoproteínas/metabolismo , Proteínas Smad/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Fosfatasa Alcalina/biosíntesis , Animales , Proteína Morfogenética Ósea 1/antagonistas & inhibidores , Proteínas de Ciclo Celular , Diferenciación Celular , Línea Celular , Subunidad alfa 1 del Factor de Unión al Sitio Principal/biosíntesis , Proteínas de la Matriz Extracelular/biosíntesis , Proteínas de la Matriz Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Flavonoides/farmacología , Ratones , Osteocalcina/biosíntesis , Fosfoproteínas/biosíntesis , Fosfoproteínas/genética , Pirazoles/farmacología , Pirimidinas/farmacología , Sialoglicoproteínas/biosíntesis , Sialoglicoproteínas/genética , Proteínas Señalizadoras YAP
14.
Neural Netw ; 171: 362-373, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38134599

RESUMEN

Due to the ubiquity of graph-structured data, Graph Neural Network (GNN) have been widely used in different tasks and domains and good results have been achieved in tasks such as node classification and link prediction. However, there are still many challenges in representation learning of heterogeneous networks. Existing graph neural network models are partly based on homogeneous graphs, which do not take into account the rich semantic information of nodes and edges due to their different types; And partly based on heterogeneous graphs, which require predefined meta-structures (include meta-paths and meta-graphs) and do not take into account the different effects of different meta-structures on node representation. In this paper, we propose the MS-GAN model, which consists of four parts: graph structure learner, graph structure expander, graph structure filter and graph structure parser. The graph structure learner automatically generates a graph structure consisting of useful meta-paths by selecting and combining the sub-adjacent matrices in the original graph using a 1 × 1 convolution. The graph structure expander further generates a graph structure containing meta-graphs by Hadamard product based on the previous step. The graph structure filterer filters out graph structures that are more effective for downstream classification tasks based on diversity. The graph structure parser assigns different weights to graph structures consisting of different meta-structures by a semantic hierarchical attention. Finally, through experiments on four datasets and meta-structure visualization analysis, it is shown that MS-GAN can automatically generate useful meta-structures and assign different weights to different meta-structures.


Asunto(s)
Aprendizaje , Redes Neurales de la Computación , Semántica , Programas Informáticos
15.
Food Chem X ; 21: 101236, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38406763

RESUMEN

Despite the favorable biocompatibility of natural antimicrobial peptides (AMPs), their scarcity limits their practical application. Through rational design, the activity of AMPs can be enhanced to expand their application. In this study, we selected a natural sturgeon epidermal mucus peptide, AP-16 (APATPAAPALLPLWLL), as the model molecule and studied its conformational regulation and antimicrobial activity through amino acid substitutions and N-terminal lipidation. The structural and morphological transitions of the peptide self-assemblies were investigated using circular dichroism and transmission electron microscopy. Following amino acid substitution, the conformation of AL-16 (AKATKAAKALLKLWLL) did not change. Following N-terminal alkylation, the C8-AL-16 and C12-AL-16 conformations changed from random coil to ß-sheet or α-helix, and the self-assembly changed from nanofibers to nanospheres. AL-16, C8-AL-16, and C8-AL-16 presented significant antimicrobial activity against Pseudomonas and Shewanella at low concentrations. N-terminal alkylation effectively extended the shelf life of Litopenaeus vannamei. These results support the application of natural AMPs.

16.
Biochim Biophys Acta Mol Cell Res ; 1871(4): 119712, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38521466

RESUMEN

Inflammatory environments can trigger endoplasmic reticulum (ER) stress and lead to pyroptosis in various tissues and cells, including liver, brain, and immune cells. As a key factor of ER stress, DNA damage-inducible transcript 3 (DDIT3)/CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP) is upregulated in osteoblasts during inflammatory stimulation. DDIT3/CHOP may therefore regulate osteoblast pyroptosis in inflammatory conditions. During this investigation, we found that lipopolysaccharides (LPS)/adenosine 5'-triphosphate (ATP) stimulation in vitro induced osteoblasts to undergo pyroptosis, and the expression of DDIT3/CHOP was increased during this process. The overexpression of DDIT3/CHOP further promoted osteoblast pyroptosis as evidenced by the increased expression of the inflammasome NLR family pyrin domain containing 3 (NLRP3) and ratios of caspase-1 p20/caspase-1 and cleaved gasdermin D (GSDMD)/GSDMD. To explore the specific mechanism of this effect, we found through fluorescence imaging and Western blot analysis that LPS/ATP stimulation promoted PTEN-induced kinase 1 (PINK1)/E3 ubiquitin-protein ligase parkin (Parkin)-mediated mitophagy in osteoblasts, and this alteration was suppressed by the DDIT3/CHOP overexpression, resulting in increased ratio of pyroptosis compared with the control groups. The impact of DDIT3/CHOP on pyroptosis in osteoblasts was reversed by the application of carbonyl cyanide 3-chlorophenylhydrazone (CCCP), a specific mitophagy agonist. Therefore, our data demonstrated that DDIT3/CHOP promotes osteoblast pyroptosis by inhibiting PINK1/Parkin-mediated mitophagy in an inflammatory environment.


Asunto(s)
Lipopolisacáridos , Piroptosis , Lipopolisacáridos/farmacología , Mitofagia , Caspasa 1/metabolismo , Caspasa 1/farmacología , Adenosina Trifosfato/metabolismo , Osteoblastos/metabolismo , Proteínas Quinasas , Ubiquitina-Proteína Ligasas/farmacología
17.
Bone ; 182: 117058, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38408589

RESUMEN

The coordination of osteoblasts and osteoclasts is essential for bone remodeling. DNA damage inducible script 3 (DDIT3) is an important regulator of bone and participates in cell differentiation, proliferation, autophagy, and apoptosis. However, its role in bone remodeling remains unexplored. Here, we found that Ddit3 knockout (Ddit3-KO) enhanced both bone formation and resorption. The increased new bone formation and woven bone resorption, i.e., enhanced bone remodeling capacity, was found to accelerate bone defect healing in Ddit3-KO mice. In vitro experiments showed that DDIT3 inhibited both osteoblast differentiation and Raw264.7 cell differentiation by regulating autophagy. Cell coculture assay showed that Ddit3-KO decreased the ratio of receptor activator of nuclear factor-κß ligand (RANKL) to osteoprotegerin (OPG) in osteoblasts, and Ddit3-KO osteoblasts inhibited osteoclast differentiation. Meanwhile, DDIT3 knockdown (DDIT3-sh) increased receptor activator of nuclear factor-κß (RANK) expression in Raw264.7 cells, and DDIT3-sh Raw264.7 cells promoted osteoblast differentiation, whereas, DDIT3 overexpression had the opposite effect. Mechanistically, DDIT3 promoted autophagy partly by increasing ULK1 phosphorylation at serine555 (pULK1-S555) and decreasing ULK1 phosphorylation at serine757 (pULK1-S757) in osteoblasts, thereby inhibiting osteoblast differentiation. DDIT3 inhibited autophagy partly by decreasing pULK1-S555 in Raw264.7 cells, thereby suppressing osteoclastic differentiation. Taken together, our data indicate that DDIT3 is one of the elements regulating bone remodeling and bone healing, which may become a potential target in bone defect treatment.


Asunto(s)
Homólogo de la Proteína 1 Relacionada con la Autofagia , Remodelación Ósea , Osteoblastos , Osteoclastos , Factor de Transcripción CHOP , Animales , Ratones , Autofagia , Resorción Ósea/metabolismo , Diferenciación Celular/fisiología , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteoprotegerina/metabolismo , Ligando RANK/metabolismo , Factor de Transcripción CHOP/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo
18.
CNS Neurosci Ther ; 30(6): e14810, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38887969

RESUMEN

AIMS: To study the changes in cortical thickness and subcortical gray matter structures in children with complete spinal cord injury (CSCI), reveal the possible causes of dysfunction beyond sensory motor dysfunction after CSCI, and provide a possible neural basis for corresponding functional intervention training. METHODS: Thirty-seven pediatric CSCI patients and 34 age-, gender-matched healthy children as healthy controls (HCs) were recruited. The 3D high-resolution T1-weighted structural images of all subjects were obtained using a 3.0 Tesla MRI system. Statistical differences between pediatric CSCI patients and HCs in cortical thickness and volumes of subcortical gray matter structures were evaluated. Then, correlation analyses were performed to analyze the correlation between the imaging indicators and clinical characteristics. RESULTS: Compared with HCs, pediatric CSCI patients showed decreased cortical thickness in the right precentral gyrus, superior temporal gyrus, and posterior segment of the lateral sulcus, while increased cortical thickness in the right lingual gyrus and inferior occipital gyrus. The volume of the right thalamus in pediatric CSCI patients was significantly smaller than that in HCs. No significant correlation was found between the imaging indicators and the injury duration, sensory scores, and motor scores of pediatric CSCI patients. CONCLUSIONS: These findings demonstrated that the brain structural reorganizations of pediatric CSCI occurred not only in sensory motor areas but also in cognitive and visual related brain regions, which may suggest that the visual processing, cognitive abnormalities, and related early intervention therapy also deserve greater attention beyond sensory motor rehabilitation training in pediatric CSCI patients.


Asunto(s)
Corteza Cerebral , Imagen por Resonancia Magnética , Traumatismos de la Médula Espinal , Humanos , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/diagnóstico por imagen , Femenino , Masculino , Niño , Adolescente , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Sustancia Gris/patología , Sustancia Gris/diagnóstico por imagen , Tamaño de los Órganos
19.
Heliyon ; 10(2): e24569, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38312693

RESUMEN

In this study, we observed pediatric complete spinal cord injury (CSCI) patients receiving MI training and divided them into different groups according to the effect of motor imagery (MI) training on neuropathic pain (NP). Then, we retrospectively analysed the differences in brain structure of these groups before the MI training, identifying brain regions that may predict the effect of MI on NP. Thirty pediatric CSCI patients were included, including 12 patients who experienced NP during MI and 18 patients who did not experience NP during MI according to the MI training follow-up. The 3D high-resolution T1-weighted images of all subjects were obtained using a 3.0 T MRI system before MI training. A two-sample t-test was performed to evaluate the differences in gray matter volume (GMV) between patients who experienced NP and those who did not experience NP during MI. Receiver operating characteristic (ROC) analysis was performed to compute the sensitivity and specificity of the imaging biomarkers for the effect of MI on NP in pediatric CSCI patients. MI evoked NP in some of the pediatric CSCI patients. Compared with patients who did not experience NP, patients who experienced NP during MI showed larger GMV in the right primary sensorimotor cortex (PSMC) and insula. When using the GMV of the right PSMC and insula in combination as a predictor, the area under the curve (AUC) reached 0.824. Our study demonstrated that MI could evoke NP in some pediatric CSCI patients, but not in others. The individual differences in brain reorganization of the right PSMC and insula may contribute to the different effects of MI on NP. Moreover, the GMV of the right PSMC and insula in combination may be an effective indicator for screening pediatric CSCI patients before MI training therapy.

20.
IEEE Trans Pattern Anal Mach Intell ; 45(7): 8063-8080, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37018637

RESUMEN

While graph representation learning methods have shown success in various graph mining tasks, what knowledge is exploited for predictions is less discussed. This paper proposes a novel Adaptive Subgraph Neural Network named AdaSNN to find critical structures in graph data, i.e., subgraphs that are dominant to the prediction results. To detect critical subgraphs of arbitrary size and shape in the absence of explicit subgraph-level annotations, AdaSNN designs a Reinforced Subgraph Detection Module to search subgraphs adaptively without heuristic assumptions or predefined rules. To encourage the subgraph to be predictive at the global scale, we design a Bi-Level Mutual Information Enhancement Mechanism including both global-aware and label-aware mutual information maximization to further enhance the subgraph representations in the perspective of information theory. By mining critical subgraphs that reflect the intrinsic property of a graph, AdaSNN can provide sufficient interpretability to the learned results. Comprehensive experimental results on seven typical graph datasets demonstrate that AdaSNN has a significant and consistent performance improvement and provides insightful results.

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