Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 133
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-39255082

RESUMO

Recently, mask-fill-based 3D Molecular Generation (MG) methods have become very popular in virtual drug design. However, the existing MG methods ignore the chemical properties of atoms and contain inappropriate atomic position training data, which limits their generation capability. To mitigate the above issues, this paper presents a novel mask-fill-based 3D molecule generation model driven by atomic chemical properties (APMG). Specifically, we construct a new attention-MPNN-based encoder and introduce the electronic information into atom representations to enrich chemical properties. Also, a multi-functional classifier is designed to predict the electronic information of each generated atom, guiding the type prediction of elements and bonds. By design, the proposed method uses the chemical properties of atoms and their correlations for high-quality molecule generation. Second, to optimize the atomic position training data, we propose a novel atomic training position generation approach using the Chi-Square distribution. We evaluate our APMG method on the CrossDocked dataset and visualize the docking states of the pockets and generated molecules. The obtained results demonstrate the superiority and merits of APMG over the state-of-the-art approaches. The dataset and codes will be available on the project homepage: https://github.com/JU-HuaY/APMG.

2.
Research (Wash D C) ; 7: 0465, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39221030

RESUMO

Although microgravity has been implicated in osteoporosis, the precise molecular mechanism remains elusive. Here, we found that microgravity might induce mitochondrial protein buildup in skeletal muscle, alongside reduced levels of LONP1 protein. We revealed that disruptions in mitochondrial proteolysis, induced by the targeted skeletal muscle-specific deletion of the essential mitochondrial protease LONP1 or by the acute inducible deletion of muscle LONP1 in adult mice, cause reduced bone mass and compromised mechanical function. Moreover, the bone loss and weakness phenotypes were recapitulated in skeletal muscle-specific overexpressing ΔOTC mice, a known protein degraded by LONP1. Mechanistically, mitochondrial proteostasis imbalance triggered the mitochondrial unfolded protein response (UPRmt) in muscle, leading to an up-regulation of multiple myokines, including FGF21, which acts as a pro-osteoclastogenic factor. Surprisingly, this mitochondrial proteostasis stress influenced muscle-bone crosstalk independently of ATF4 in skeletal muscle. Furthermore, we established a marked association between serum FGF21 levels and bone health in humans. These findings emphasize the pivotal role of skeletal muscle mitochondrial proteostasis in responding to alterations in loading conditions and in coordinating UPRmt to modulate bone metabolism.

3.
Neural Netw ; 179: 106602, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39153400

RESUMO

In the majority of existing multi-view clustering methods, the prerequisite is that the data have the correct cross-view correspondence. However, this strong assumption may not always hold in real-world applications, giving rise to the so-called View-shuffled Problem (VsP). To address this challenge, we propose a novel multi-view clustering method, namely View-shuffled Clustering via the Modified Hungarian Algorithm (VsC-mH). Specifically, we first establish the cross-view correspondence of the shuffled data utilizing strategies of the global alignment and modified Hungarian algorithm (mH) based intra-category alignment. Subsequently, we generate the partition of the aligned data employing matrix factorization. The fusion of these two processes facilitates the interaction of information, resulting in improved quality of both data alignment and partition. VsC-mH is capable of handling the data with alignment ratios ranging from 0 to 100%. Both experimental and theoretical evidence guarantees the convergence of the proposed optimization algorithm. Extensive experimental results obtained on six practical datasets demonstrate the effectiveness and merits of the proposed method.

4.
Sci Data ; 11(1): 838, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095383

RESUMO

Branch retinal vein occlusion (BRVO) is the most prevalent retinal vascular disease that constitutes a threat to vision due to increased venous pressure caused by venous effluent in the space, leading to impaired visual function. Optical Coherence Tomography Angiography (OCTA) is an innovative non-invasive technique that offers high-resolution three-dimensional structures of retinal blood vessels. Most publicly available datasets are collected from single visits with different patients, encompassing various eye diseases for distinct tasks and areas. Moreover, due to the intricate nature of eye structure, professional labeling not only relies on the expertise of doctors but also demands considerable time and effort. Therefore, we have developed a BRVO-focused dataset named Soul (Source of ocular vascular) and propose a human machine collaborative annotation framework (HMCAF) using scrambled retinal blood vessels data. Soul is categorized into 6 subsets based on injection frequency and follow-up duration. The dataset comprises original images, corresponding blood vessel labels, and clinical text information sheets which can be effectively utilized when combined with machine learning.


Assuntos
Aprendizado de Máquina , Oclusão da Veia Retiniana , Vasos Retinianos , Tomografia de Coerência Óptica , Humanos , Vasos Retinianos/diagnóstico por imagem
5.
ACS Appl Mater Interfaces ; 16(32): 42995-43005, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39092637

RESUMO

The use of solid electrolytes (SE) in solid-state batteries holds the promise of achieving higher energy densities and enhancing safety. However, current solid-state batteries face significant interface impedance issues, mainly dealing with the effect of the evolution of the solid-solid interface on ion transport. Semi-solid-state batteries (SSB), containing a small amount of liquid electrolyte, serve as appropriate transitional products in the development process of solid-state batteries. More importantly, the clarity of the relevant interface dynamics can provide theoretical guidance for the subsequent all-solid-state batteries. Therefore, this paper investigates SSB through Electrochemical Impedance Spectroscopy (EIS), primarily employing a combination of theoretical modeling, simulation predictions, and experimental analyses to elucidate the complex electrochemical processes within these batteries. Based on detailed exploration of the complex electrochemical processes within SSB, we have discovered additional electrochemical processes beyond Li+ penetration through the solid-electrolyte interphase (SEI) film and charge transfer. We attribute the additional electrochemical reaction processes to the resistance present at the SE/SEI interface of SSB on account of numerical analysis and interface characterization. Furthermore, this interface resistance exhibits a trend of initial decrease followed by continuous increase, elucidating the attribution and numerical variations of various impedance components within the EIS. The application of EIS techniques to analyze ion transport processes in SSB serves as a suitable transition toward achieving all-solid-state batteries as well as provides guidance for subsequent interface optimization of solid-state batteries and propels their transition from laboratory experimentation to commercialization.

6.
Artigo em Inglês | MEDLINE | ID: mdl-39206768

RESUMO

STUDY DESIGN: A genetic case-control study. OBJECTIVES: To investigate the association between AIS progression-associated SNPs reported by GWAS studies and the effectiveness of brace treatment. SUMMARY OF BACKGROUND DATA: Bracing is the most effective conservative method to treat adolescent idiopathic scoliosis (AIS). Several factors have been reported to be associated with bracing failure in AIS patients. Genetic markers associated with AIS have potential prognostic value. METHODS: A retrospective cohort of AIS patients undergoing brace treatment was enrolled in this study and divided into success and failure groups based on treatment outcome. Clinical characteristics of AIS patients were documented. Candidate SNPs were selected from previous GWAS studies of AIS, which were known to be associated with curve progression and validated across diverse populations. Genotype and allele frequencies between the success and failure groups were compared using chi-square analysis. RESULTS: A total of 259 female AIS patients were included in this study, 30.5% of the well-braced patients had curve progression exceeding 5° and 69.5% of the patients undergo an improvement or progression of less than 5°. Allele C of rs10738445 (BNC2) could significantly add to the risk of bracing failure, with odds ratio of 1.59. No significant association with bracing outcomes was found for rs12946942 (SOX9/KCNJ2), rs1978060 (TBX1), rs1017861 (CHD7), and rs35333564 (MIR4300HG). CONCLUSIONS: SNP rs10738445 were significantly associated with brace treatment effectiveness. The other four SNPs were not significantly associated with the outcome of bracing. More SNPs and predictors should be included in future study to develop a more accurate predictive model for clinical application.

8.
Front Vet Sci ; 11: 1382239, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38978635

RESUMO

Both acute and chronic tendon injuries are the most frequently occurring musculoskeletal diseases in human and veterinary medicine, with a limited repertoire of successful and evidenced-based therapeutic strategies. Inflammation has been suggested as a key driver for the formation of scar and adhesion tissue following tendon acute injury, as well as pathological alternations of degenerative tendinopathy. However, prior efforts to completely block this inflammatory process have yet to be largely successful. Recent investigations have indicated that a more precise targeted approach for modulating inflammation is critical to improve outcomes. The nuclear factor-kappaB (NF-κB) is a typical proinflammatory signal transduction pathway identified as a key factor leading to tendon disorders. Therefore, a comprehensive understanding of the mechanism or regulation of NF-κB in tendon disorders will aid in developing targeted therapeutic strategies for human and veterinary tendon disorders. In this review, we discuss what is currently known about molecular components and structures of basal NF-κB proteins and two activation pathways: the canonical activation pathway and the non-canonical activation pathway. Furthermore, we summarize the underlying mechanisms of the NF-κB signaling pathway in fibrosis and adhesion after acute tendon injury, as well as pathological changes of degenerative tendinopathy in all species and highlight the effect of targeting this signaling pathway in tendon disorders. However, to gain a comprehensive understanding of its mechanisms underlying tendon disorders, further investigations are required. In the future, extensive scientific examinations are warranted to full characterize the NF-κB, the exact mechanisms of action, and translate findings into clinical human and veterinary practice.

9.
Cell Prolif ; : e13720, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39045886

RESUMO

Intervertebral discs (IVDs) are rhythmic tissues that experience daily low-load recovery. Notably, aging and abnormal mechanical stress predispose IVDs to degeneration due to dysrhythmia-induced disordered metabolism. Meanwhile, Rev-erbα acts as a transcriptional repressor in maintaining biorhythms and homeostasis; however, its function in IVD homeostasis and degeneration remains unclear. This study assessed the relationship between low Rev-erbα expression levels and IVD degeneration. Rev-erbα deficiency accelerated needle puncture or aging-induced IVD degeneration, characterized by increased extracellular matrix (ECM) catabolism and nucleus pulposus (NP) cell apoptosis. Mechanistically, Rev-erbα knockdown in NP cells aggravated rhIL1ß-induced NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome activation, exacerbating the imbalanced ECM and NP cell apoptosis. Meanwhile, blocking NLRP3 inflammasome activation mitigated Rev-erbα deficiency and needle puncture-induced IVD degeneration. Particularly, Rev-erbα mediated the transcriptional repression of the NLRP3 inflammasome via the ligand heme-binding of nuclear receptor co-repressor (NCoR) and histone deacetylase 3 (HDAC3) complex. Thus, the increased expression of Rev-erbα in NP cells following short-term rhIL1ß treatment failed to inhibit NLRP3 transcription in vitro owing to heme depletion. Pharmacological activation of Rev-erbα in vivo and in vitro alleviated IVD degeneration by altering the NLRP3 inflammasome. Taken together, targeting Rev-erbα may be a potential therapeutic strategy for alleviating IVD degeneration and its related diseases.

10.
Int Immunopharmacol ; 137: 112531, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38906009

RESUMO

The role of oxidative stress and ferroptosis in osteoarthritis (OA) pathogenesis is increasingly recognized. Notably, 4-octyl Itaconate (OI) has been documented to counteract oxidative stress and inflammatory responses, highlighting its therapeutic potential in OA. This study explored the effects of OI on GPX4 methylation, oxidative stress, and ferroptosis in chondrocytes affected by OA. Our results demonstrated that OI mitigated IL-1ß-induced chondrocyte degeneration in a dose-dependent manner. It also suppressed reactive oxygen species (ROS) production and sustained GPX4 expression, thereby attenuating the degenerative impact of IL-1ß and Erastin on chondrocytes by curtailing ferroptosis. Moreover, we observed that blocking GPX4 methylation could alleviate IL-1ß-induced degeneration, oxidative stress, and ferroptosis in chondrocytes. The regulatory mechanism of OI on GPX4 expression in chondrocytes involved the inhibition of GPX4 methylation. In a mouse model of OA, OI's protective effects against OA were comparable to those of Ferrostatin-1. Thus, OI reduced chondrocyte degeneration, oxidative stress, and ferroptosis by inhibiting GPX4 methylation, offering a novel mechanistic insight into its therapeutic application in OA.


Assuntos
Condrócitos , Ferroptose , Interleucina-1beta , Camundongos Endogâmicos C57BL , Osteoartrite , Estresse Oxidativo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Succinatos , Animais , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Ferroptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Succinatos/farmacologia , Succinatos/uso terapêutico , Interleucina-1beta/metabolismo , Osteoartrite/tratamento farmacológico , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Camundongos , Masculino , Humanos , Metilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Células Cultivadas , Modelos Animais de Doenças
11.
Spine J ; 24(8): 1407-1415, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38631491

RESUMO

BACKGROUND CONTEXT: Vertebral endplate defects are often implicated in degenerative disc disorders, yet their connection to patient-reported symptoms remains unclear. COX-2 and PGE-2 are known for their roles in inflammation and pain, with EP-4 receptor involvement in pain signaling. Examining their expression in vertebral endplate tissues may provide insights into pathomechanism of low back pain. PURPOSE: To investigate the association between endplate defects and patient-reported symptoms and to further clarify the role of the COX-2/PGE-2/EP-4 axis in the pathogenesis of chronic low back pain. STUDY DESIGN/SETTING: Retrospective study. PATIENT SAMPLE: A total of 71 patients who had undergone single-level L4/5 or L5/S1 modified laminectomy decompression preserving proximal upper laminae and transforaminal lumbar interbody fusion surgery were included in this study, including 18 patients diagnosed with lumbar disc herniation, 19 with lumbar disc herniation accompanied by degenerative lumbar spinal stenosis, and 34 with degenerative spondylolisthesis. OUTCOME MEASURES: Demographic data, Pfirrmann grade, Modic changes, endplate defect score, visual analog scale (VAS) for back and leg pain, and Oswestry Disability Index (ODI) before surgery, 3-month and 6-month follow-up, and the percentage of immune-positive cells (COX-2, PGE-2, and EP-4) in endplate tissue sections. METHODS: Patients were divided into defect and nondefect groups according to endplate morphology on lumbar MR. All intraoperative endplate specimens were immediately fixed in 10% formaldehyde, and then embedded in paraffin 3 days later for tissue sections. The outcome measures were compared between the defect group and nondefect group. Data were analyzed using independent t-tests and χ² tests. Pearson's rank correlation test was used to assess correlations between patient-reported symptoms and the percentage of immune-positive cells in the groups. Multivariable logistic regression models using the forward stepwise likelihood ratio method were used to identify the factors that were independently associated with endplate defects. RESULTS: The age of Defect group was significantly higher than that of nondefect group (52.5±7.7 vs 57.2±9.1. p=.024). There were no significant differences in gender, diagnosis, BMI, comorbidities, or surgical level between the two groups. Modic changes (Type Ⅱ/Type Ⅲ) were more common in patients of Defect group than nondefect group (38.5% vs 11.1%, p<.001), and so was disc degeneration (Pfirrmann grade Ⅳ/Ⅴ) (69.2% vs 33.3%, p<.001). Defect group had significantly higher VAS-Back (6.5±2.0 vs 4.9±1.6, p<.001) and ODI scores (62.9±10.7 vs 45.2±14.8, p<.001) than nondefect group, while there was no significant differences between the two groups during the 3 and 6-month follow-up after surgery. Histologically, Defect group was characterized by upregulation of COX-2, PGE-2, and EP-4 in endplate tissue sections. Both in defect and nondefect groups, VAS-Back showed moderate positive correlations with the expressions of COX-2 (r=0.643; r=0.558, p both<.001), PGE-2 (r=0.611; r=0.640, p both<.001), and EP-4 (r=0.643; r=0.563, p both<.001). Multivariate regression analyses reveled that percentage of COX-2-positive cells was associated with endplate defects (OR=1.509, 95%CI [1.048-2.171], p=.027), as well as percentage of PGE-2-positive (OR=1.291, 95%CI [1.106-1.508], p=.001) and EP-4-positive cells (OR=1.284, 95%CI [1.048∼2.171], p=.003). CONCLUSIONS: Patients with endplate defects had worse quality of life, more severe disc degeneration and Modic changes, and up-regulated COX-2/PGE-2/EP-4 axis expression in cartilage endplates in patients with defected endplates. Inflammatory factors may significantly contribute to the onset and progression of chronic low back pain in patients with endplate defects, consequently impacting patient-reported symptoms.


Assuntos
Ciclo-Oxigenase 2 , Dinoprostona , Dor Lombar , Vértebras Lombares , Receptores de Prostaglandina E Subtipo EP4 , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Ciclo-Oxigenase 2/metabolismo , Vértebras Lombares/cirurgia , Dor Lombar/patologia , Idoso , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Estudos Retrospectivos , Dinoprostona/metabolismo , Adulto , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/cirurgia , Deslocamento do Disco Intervertebral/metabolismo , Deslocamento do Disco Intervertebral/cirurgia , Deslocamento do Disco Intervertebral/patologia , Estenose Espinal/cirurgia , Estenose Espinal/patologia , Fusão Vertebral , Espondilolistese/cirurgia , Espondilolistese/patologia , Medidas de Resultados Relatados pelo Paciente , Imuno-Histoquímica
12.
Exp Mol Med ; 56(5): 1178-1192, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38689089

RESUMO

Modic changes are radiographic features associated with microfracture, low-virulence organism infection and chronic inflammation with inflammatory cell infiltration in the vertebral endplate region. Mast cells, as innate immune cells similar to macrophages, are present in painful degenerated intervertebral discs. However, the involvement and mechanisms of mast cells in the development of Modic changes remain unclear. Herein, we found increased mast cell infiltration in samples from patients with Modic changes and in mouse models of Modic changes. To clarify the role of mast cells in the progression of Modic changes, we used mast cell-deficient (KITW-SH/W-SH) mice to construct a model of Modic changes and found that the severity of Modic changes in KITW-SH/W-SH mice was significantly lower than that in WT mice. These findings were further supported by the use of a mast cell-specific activator (compound 48/80) and a stabilizer (cromolyn). Furthermore, we found that mast cells were not activated via the classic IgE pathway in the Modic change models and that Mrgprb2 is the specific receptor for mast cell activation reported in recent studies. Then, we utilized Mrgprb2 knockout mice to demonstrate that Mrgprb2 knockout inhibited mast cell activation and thus reduced the degree of Modic changes. Transcriptomic sequencing revealed aberrant PI3K-AKT and MAPK pathway activation in the Mrgprb2-deficient mast cells. Additionally, Mrgpbrb2-activated mast cells regulate immune niches by recruiting macrophages, promoting M1 polarization and reducing M2 polarization, thereby promoting the progression of Modic changes. These findings suggest that mast cells may serve as a novel therapeutic target for addressing Modic changes.


Assuntos
Mastócitos , Camundongos Knockout , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Modelos Animais de Doenças , Degeneração do Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/imunologia , Degeneração do Disco Intervertebral/genética , Mastócitos/imunologia , Mastócitos/metabolismo , Transdução de Sinais
13.
Materials (Basel) ; 17(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38591540

RESUMO

The control of the solidification structure of a casting billet is directly correlated with the quality of steel. Variations in superheat can influence the transition from columnar crystals to equiaxed crystals during the solidification process, subsequently impacting the final solidification structure of the billet. In this study, a model of microstructure evolution during billet solidification was established by combining simulation and experiment, and the dendrite growth microstructure evolution during billet solidification under different superheat was studied. The results show that when the superheat is 60 K, the complete solidification time of the casting billet from the end of the 50 mm section is 252 s, when the superheat is 40 K, the complete solidification time of the casting billet is 250 s, and when the superheat is 20 K, the complete solidification time of the casting billet is 245 s. When the superheat is 20 K, the proportion of the equiaxed crystal region is higher-the highest value is 53.35%-and the average grain radius is 0.84556 mm. The proportion of the equiaxed crystal region decreases with the increase of superheat. When the superheat is 60 K, the proportion of the equiaxed crystal region is the lowest-the lowest value is 46.27%-and the average grain radius is 1.07653 mm. Proper reduction of superheat can obviously reduce the size of equiaxed crystal, expand the area of equiaxed crystal and improve the quality of casting billet.

14.
J Bone Miner Res ; 39(6): 737-752, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38477781

RESUMO

Lipid metabolism plays a crucial role in maintaining bone homeostasis, particularly in osteoclasts (OCs) formation. Here, we found that the expression level of FATP2, a transporter for long-chain and very-long-chain fatty acids, was significantly upregulated during OC differentiation and in the bone marrow of mice fed a high-fat diet (HFD). Notably, the use of FATP2 siRNA or a specific inhibitor (Lipofermata) resulted in significant inhibition of OC differentiation, while only slightly affecting osteoblasts. In pathological models of bone loss induced by LPS or ovariectomy, in vivo treatment with Lipofermata was able to rescue the loss of bone mass by inhibiting OC differentiation. RNA sequencing revealed that Lipofermata reduced fatty acid ß-oxidation and inhibited energy metabolism, while regulating ROS metabolism to decrease ROS production, ultimately inhibiting OC differentiation. Treatment with Lipofermata, either in vivo or in vitro, effectively rescued the overactivation of OCs, indicating that FATP2 regulated OC differentiation by modulating fatty acid uptake and energy metabolism. These findings suggested that targeting FATP2 may represent a promising therapeutic approach for pathological osteoporosis.


The inhibition of osteoclastogenesis by Lipofermata, a FATP2 inhibitor, was achieved through the reprogramming of energy metabolism and regulation of ROS levels. In both pathological bone loss and HFD-induced osteoporosis models, the expression levels of FATP2 were significantly upregulated, and Lipofermata demonstrated potential therapeutic effects in the pathological bone loss model.


Assuntos
Diferenciação Celular , Metabolismo dos Lipídeos , Osteoclastos , Osteogênese , Espécies Reativas de Oxigênio , Animais , Metabolismo dos Lipídeos/efeitos dos fármacos , Osteoclastos/metabolismo , Camundongos , Osteogênese/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Feminino , Camundongos Endogâmicos C57BL , Proteínas de Transporte de Ácido Graxo/metabolismo , Proteínas de Transporte de Ácido Graxo/genética , Dieta Hiperlipídica
15.
J Integr Plant Biol ; 66(5): 897-908, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38506424

RESUMO

The phytohormone jasmonate (JA) coordinates stress and growth responses to increase plant survival in unfavorable environments. Although JA can enhance plant UV-B stress tolerance, the mechanisms underlying the interaction of UV-B and JA in this response remain unknown. In this study, we demonstrate that the UV RESISTANCE LOCUS 8 - TEOSINTE BRANCHED1, Cycloidea and PCF 4 - LIPOXYGENASE2 (UVR8-TCP4-LOX2) module regulates UV-B tolerance dependent on JA signaling pathway in Arabidopsis thaliana. We show that the nucleus-localized UVR8 physically interacts with TCP4 to increase the DNA-binding activity of TCP4 and upregulate the JA biosynthesis gene LOX2. Furthermore, UVR8 activates the expression of LOX2 in a TCP4-dependent manner. Our genetic analysis also provides evidence that TCP4 acts downstream of UVR8 and upstream of LOX2 to mediate plant responses to UV-B stress. Our results illustrate that the UV-B-dependent interaction of UVR8 and TCP4 serves as an important UVR8-TCP4-LOX2 module, which integrates UV-B radiation and JA signaling and represents a new UVR8 signaling mechanism in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ciclopentanos , Regulação da Expressão Gênica de Plantas , Oxilipinas , Raios Ultravioleta , Arabidopsis/efeitos da radiação , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Transdução de Sinais/efeitos da radiação , Proteínas Cromossômicas não Histona/metabolismo , Proteínas Cromossômicas não Histona/genética , Lipoxigenase/metabolismo , Lipoxigenase/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Ligação Proteica/efeitos da radiação , Adaptação Fisiológica/efeitos da radiação , Adaptação Fisiológica/genética , Núcleo Celular/metabolismo , Lipoxigenases
16.
Food Funct ; 15(7): 3552-3565, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38465899

RESUMO

Osteoarthritis is the most prevalent degenerative joint disease reported worldwide. Conventional treatment strategies mainly focus on medication and involve surgical joint replacement. The use of these therapies is limited by gastrointestinal complications and the lifespan of joint prostheses. Hence, safe and efficacious drugs are urgently needed to impede the osteoarthritis progression. Urolithin B, a metabolite of ellagic acid in the gut, exhibits anti-inflammatory and antioxidant properties; however, its role in osteoarthritis remains unclear. In this study, we demonstrated that urolithin B efficiently inhibits the inflammatory factor-induced production of matrix metalloproteinases (MMP3 and MMP13) in vitro and upregulates the expression of type II collagen and aggrecan. Urolithin B alleviates cartilage erosion and osteophyte formation induced by anterior cruciate ligament transections. Moreover, urolithin B inhibits the activation of the NF-κB pathway by reducing the phosphorylation of Iκb-α and the nuclear translocation of P65. In summary, urolithin B significantly inhibits inflammation and alleviates osteoarthritis. Hence, urolithin B can be considered a potential agent suitable for the effective treatment of osteoarthritis in the future.


Assuntos
Cumarínicos , Osteoartrite , Transdução de Sinais , Humanos , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Condrócitos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Cartilagem/metabolismo , Interleucina-1beta/metabolismo
17.
Neural Netw ; 174: 106224, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38479186

RESUMO

Adversarial training has become the mainstream method to boost adversarial robustness of deep models. However, it often suffers from the trade-off dilemma, where the use of adversarial examples hurts the standard generalization of models on natural data. To study this phenomenon, we investigate it from the perspective of spatial attention. In brief, standard training typically encourages a model to conduct a comprehensive check to input space. But adversarial training often causes a model to overly concentrate on sparse spatial regions. This reduced tendency is beneficial to avoid adversarial accumulation but easily makes the model ignore abundant discriminative information, thereby resulting in weak generalization. To address this issue, this paper introduces an Attention-Enhanced Learning Framework (AELF) for robustness training. The main idea is to enable the model to inherit the attention pattern of standard pre-trained model through an embedding-level regularization. To be specific, given a teacher model built on natural examples, the embedding distribution of teacher model is used as a static constraint to regulate the embedding outputs of the objective model. This design is mainly supported with that the embedding feature of standard model is usually recognized as a rich semantic integration of input. For implementation, we present a simplified AELFs that can achieve the regularization with single cross entropy loss via the parameter initialization and parameter update strategy. This avoids the extra consistency comparison operation between embedding vectors. Experimental observations verify the rationality of our argument, and experimental results demonstrate that it can achieve remarkable improvements in generalization under the high-level robustness.


Assuntos
Generalização Psicológica , Aprendizagem , Entropia , Semântica
18.
Cell Death Discov ; 10(1): 80, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360705

RESUMO

Bone and mineral metabolism homeostasis accounts for the maintenance of normal skeletal remodeling. However, with aging and changes in hormone levels, over-activated osteoclasts disrupt homeostasis, induce osteoporosis, and even cause osteoporotic fractures, leading to an enormous economic burden. Despite the rapid development of pharmacological therapy for osteoporosis, safer and more effective treatments remain to be explored. Here, we demonstrate that Mulberroside A (Mul-A), a natural component extracted from mulberry bark and branches, effectively suppresses osteoclastogenesis in vitro and counteracts bone loss caused by ovariectomy (OVX). The mechanism underlying this effect involves the repression of autophagic flux during osteoclastogenesis by Mul-A, which can be attributed to the restrained expression of microphthalmia-related transcription factor (Mitf) and its nuclear translocation. Importantly, Mitf overexpression partially reverses the inhibitory effects of Mul-A on autophagy and osteoclastogenesis. Moreover, applying two autophagy agonizts, rapamycin and Torin 1, attenuates the osteoclastogenic regulatory role of Mul-A. Collectively, our study demonstrates that Mul-A damages osteoclast differentiation and ameliorates osteoporosis caused by estrogen deficiency by modulation of Mitf-associated autophagy, indicating its therapeutic potential against osteoporosis.

19.
Cont Lens Anterior Eye ; 47(2): 102127, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38350814

RESUMO

PURPOSE: The aim of this study was to evaluate the long-term effects of serial intravitreal injections (IVI) on measures of dry eye. METHODS: The PubMed, EMBASE, and Cochrane databases were searched according to the PROSPERO protocol (CRD42023455727). Studies evaluating the influence of serial IVI on the ocular surface compared with untreated fellow eyes were included. The measures of dry eye after IVI were used as outcome variables. The results are presented as mean difference (MD) with a corresponding 95% confidence interval (CI). RESULTS: A total of 4 studies with 259 participants were included in this meta-analysis. Significant increases in ocular surface disease index (OSDI) scores (MD 10.26, 95 % CI 5.05 to 15.46, p < 0.01) and tear film osmolarity (TOsm; MD 4.40, 95 % CI 0.87 to 7.92, p = 0.01) were observed in the IVI treated eyes compared to the untreated fellow eyes. There was no significant difference between the groups with respect to fluorescein tear film break-up time (TBUT; p = 0.05), average non-invasive tear film break-up time (NITBUT; p = 0.94), first NITBUT (p = 0.78) and Schirmer test (p = 0.94). CONCLUSION: Repeated IVI of anti-VEGF agents with preoperative povidone-iodine application was associated with increased OSDI scores and TOsm, while no significant difference was found in fluorescein TBUT, average NITBUT, first NITBUT and Schirmer test. The ocular surface may partially recover after the procedures, but IVI still has deleterious effects on the ocular surface.


Assuntos
Síndromes do Olho Seco , Humanos , Injeções Intravítreas , Síndromes do Olho Seco/tratamento farmacológico , Povidona-Iodo , Lágrimas , Fluoresceína
20.
Materials (Basel) ; 17(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38276469

RESUMO

In this study, a three-dimensional segmented coupled model for continuous casting billets under combined mold and final electromagnetic stirring (M-EMS, F-EMS) was developed. The model was verified by comparing carbon segregation in billets with and without EMS through plant experiments. The findings revealed that both M-EMS and F-EMS induce tangential flow in molten steel, impacting solidification and solute distribution processes within the billet. For M-EMS, with operating parameters of 250A-2Hz, the maximum tangential velocity (velocity projected onto the cross-section) was observed at the liquid phase's edge. For F-EMS, with operating parameters of 250A-6Hz, the maximum tangential velocity occurred at fl=0.7. Furthermore, F-EMS accelerated heat transfer in the liquid phase, reducing the central liquid fraction from 0.93 to 0.85. M-EMS intensified the washing effect of molten steel on the solidification front, resulting in the formation of negative segregation within the mold. F-EMS significantly improved the centerline segregation issue, reducing carbon segregation from 1.15 to 1.02. Experimental and simulation results, with and without EMS, were in good agreement, indicating that M+F-EMS leads to a more uniform solute distribution within the billet, with a pronounced improvement in centerline segregation.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA