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1.
Org Biomol Chem ; 22(39): 7951-7955, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39258429

RESUMEN

In this paper, a set of novel ternary deep eutectic solvents (T-DESs) is synthesized and applied in the esterification of 2-methylpropenoic acid with alcohols. T-DESs have multiple functions, serving as a catalyst, polymerization inhibitor, and solvent, and demonstrate excellent catalytic esterification reaction activity (up to 96% yield). The optimal T-DESs 1 can be recycled 14 times without any decrease in its catalytic activity, thus solving the problems of methacrylate product separation with a polymerization inhibitor, catalyst recovery, and organic solvent pollution.

2.
Sensors (Basel) ; 24(15)2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39123907

RESUMEN

Skeleton-based action recognition, renowned for its computational efficiency and indifference to lighting variations, has become a focal point in the realm of motion analysis. However, most current methods typically only extract global skeleton features, overlooking the potential semantic relationships among various partial limb motions. For instance, the subtle differences between actions such as "brush teeth" and "brush hair" are mainly distinguished by specific elements. Although combining limb movements provides a more holistic representation of an action, relying solely on skeleton points proves inadequate for capturing these nuances. Therefore, integrating detailed linguistic descriptions into the learning process of skeleton features is essential. This motivates us to explore integrating fine-grained language descriptions into the learning process of skeleton features to capture more discriminative skeleton behavior representations. To this end, we introduce a new Linguistic-Driven Partial Semantic Relevance Learning framework (LPSR) in this work. While using state-of-the-art large language models to generate linguistic descriptions of local limb motions and further constrain the learning of local motions, we also aggregate global skeleton point representations and textual representations (which generated from an LLM) to obtain a more generalized cross-modal behavioral representation. On this basis, we propose a cyclic attentional interaction module to model the implicit correlations between partial limb motions. Numerous ablation experiments demonstrate the effectiveness of the method proposed in this paper, and our method also obtains state-of-the-art results.


Asunto(s)
Semántica , Humanos , Lingüística , Movimiento/fisiología , Reconocimiento de Normas Patrones Automatizadas/métodos , Algoritmos , Aprendizaje/fisiología
3.
Int J Mol Sci ; 25(3)2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38339152

RESUMEN

Calcium (Ca2+) is a versatile intracellular second messenger that regulates several signaling pathways involved in growth, development, stress tolerance, and immune response in plants. Autoinhibited Ca2+-ATPases (ACAs) play an important role in the regulation of cellular Ca2+ homeostasis. Here, we systematically analyzed the putative OsACA family members in rice, and according to the phylogenetic tree of OsACAs, OsACA9 was clustered into a separated branch in which its homologous gene in Arabidopsis thaliana was reported to be involved in defense response. When the OsACA9 gene was knocked out by CRISPR/Cas9, significant accumulation of reactive oxygen species (ROS) was detected in the mutant lines. Meanwhile, the OsACA9 knock out lines showed enhanced disease resistance to both rice bacterial blight (BB) and bacterial leaf streak (BLS). In addition, compared to the wild-type (WT), the mutant lines displayed an early leaf senescence phenotype, and the agronomy traits of their plant height, panicle length, and grain yield were significantly decreased. Transcriptome analysis by RNA-Seq showed that the differentially expressed genes (DEGs) between WT and the Osaca9 mutant were mainly enriched in basal immune pathways and antibacterial metabolite synthesis pathways. Among them, multiple genes related to rice disease resistance, receptor-like cytoplasmic kinases (RLCKs) and cell wall-associated kinases (WAKs) genes were upregulated. Our results suggest that the Ca2+-ATPase OsACA9 may trigger oxidative burst in response to various pathogens and synergically regulate disease resistance and leaf senescence in rice.


Asunto(s)
Resistencia a la Enfermedad , Oryza , Resistencia a la Enfermedad/genética , Adenosina Trifosfatasas/metabolismo , Oryza/metabolismo , Senescencia de la Planta , Filogenia , Regulación de la Expresión Génica de las Plantas , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo
4.
Int J Mol Sci ; 23(24)2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36555397

RESUMEN

Hydrogels with a three-dimensional network structure are particularly outstanding in water absorption and water retention because water exists stably in the interior, making the gel appear elastic and solid. Although traditional hydrogels have good water absorption and high water content, they have poor mechanical properties and are not strong enough to be applied in some scenarios today. The proposal of double-network hydrogels has dramatically improved the toughness and mechanical strength of hydrogels that can adapt to different environments. Based on ensuring the properties of hydrogels, they themselves will not be damaged by excessive pressure and tension. This review introduces preparation methods for double-network hydrogels and ways to improve the mechanical properties of three typical gels. In addition to improving the mechanical properties, the biocompatibility and swelling properties of hydrogels enable them to be applied in the fields of biomedicine, intelligent sensors, and ion adsorption.


Asunto(s)
Hidrogeles , Agua , Hidrogeles/química , Adsorción , Agua/química
5.
Nanotechnology ; 32(6): 065502, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33086215

RESUMEN

Catalytic and electrocatalytic applications of supported metal nanoparticles are hindered due to an aggregation of metal nanoparticles and catalytic leaching under harsh operations. Hence, stable and leaching free catalysts with high surface area are extremely desirable but also challenging. Here we report a gold nanoparticles-hosted mesoporous nitrogen doped carbon matrix, which is prepared using bovine serum albumin (BSA) through calcination. BSA plays three roles in this process as a reducing agent, capping agent and carbon precursor, hence the protocol exhibits economic and sustainable. Gold nanoparticles at N-doped BSA carbon (AuNPs@NBSAC)-modified three-electrode strip-based flexible sensor system has been developed, which displayed effective, sensitive and selective for simultaneous detection of uric acid (UA) and dopamine (DA). The AuNPs@NBSAC-modified sensor showed an excellent response toward DA with a linear response throughout the concentration range from 1 to 50 µM and a detection limit of 0.05 µM. It also exhibited an excellent response toward UA, with a wide detection range from 5 to 200 µM as well as a detection limit of 0.1 µM. The findings suggest that the AuNPs@NBSAC nanohybrid reveals promising applications and can be considered as potential electrode materials for development of electrochemical biosensors.

6.
J Basic Microbiol ; 61(5): 430-442, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33683727

RESUMEN

The lentivirus-short hairpin RNA (shRNA) system is a widely used tool for RNA interference. Multiple factors may affect the RNA interference efficiency during lentivirus production and transduction procedures. Thus, an optimized protocol is required to achieve high-titer lentivirus and efficient gene delivery. In the present study, lentivirus was produced by transfecting lentiviral transfer and packaging plasmids into HEK 293T cells. The factors affecting lentiviral titer were assessed, including lentiviral plasmid ratio, lentiviral transfer plasmid type, serum type for cell culture, transfection reagent-plasmid mixture incubation time, and the inoculation density of 293T cells for transfection. The high-titer lentivirus was achieved when plasmids were transfected at a molar ratio of 1:1:1:2, and the transfection reagent-plasmid mixture was replaced 6-8 h after transfection. The pLVX-shRNA2 lentiviral transfer plasmid was associated with the highest lentiviral titer, while both pLVX-shRNA2 and psi-LVRU6GP plasmids were associated with efficient RNA interference in target cells. The serum type for 293T cell culture affected the lentiviral titer significantly, while the inoculation density of 293T cells showed no influence on transfection efficiency or lentiviral titer. Moreover, the human primary fibroblasts infected with lentivirus, using the centrifugation method, achieved higher transduction efficiency than those infected with the non-centrifugation method. In conclusion, this study helped optimize lentiviral production and transduction procedures for more efficient gene delivery.


Asunto(s)
Fibroblastos/virología , Lentivirus/genética , Lentivirus/fisiología , Transducción Genética/métodos , Células Cultivadas , Células HEK293 , Humanos , Plásmidos/genética , Interferencia de ARN , Transfección
7.
Nano Lett ; 20(6): 4330-4336, 2020 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-32375003

RESUMEN

Fluorescence-based microarrays are promising diagnostic tools due to their high throughput, small sample volume requirements, and multiplexing capabilities. However, their low fluorescence output has limited their implementation for in vitro diagnostics applications in point-of-care (POC) settings. Here, by integration of a sandwich immunoassay microarray within a plasmonic nanogap cavity, we demonstrate strongly enhanced fluorescence which is critical for readout by inexpensive POC detectors. The immunoassay consists of inkjet-printed antibodies on a polymer brush which is grown on a gold film. Colloidally synthesized silver nanocubes are placed on top and interact with the underlying gold film creating high local electromagnetic field enhancements. By varying the thickness of the brush from 5 to 20 nm, up to a 151-fold increase in fluorescence and 14-fold improvement in the limit-of-detection is observed for the cardiac biomarker B-type natriuretic peptide (BNP) compared to the unenhanced assay, paving the way for a new generation of POC clinical diagnostics.


Asunto(s)
Bioimpresión , Oro , Inmunoensayo , Plata , Humanos , Nanotecnología , Pruebas en el Punto de Atención , Polímeros
8.
Biochem Biophys Res Commun ; 517(2): 201-209, 2019 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-31331645

RESUMEN

Lung cancer is the most commonly diagnosed cancer and accounts for most cancer-related mortalities worldwide. The high expression of programmed death ligand 1 (PD-L1) is an important factor that promotes immune escape of lung cancer, thus aggravates chemotherapy resistance and poor prognosis. Therefore, understanding the regulatory mechanism of PD-L1 in lung cancer is critical for tumor immunotherapy. Enhancer of Zeste homolog2 (EZH2), an epigenetic regulatory molecule with histone methyltransferase activity, promotes the formation of an immunosuppressive microenvironment. This study aimed to investigate the role of EZH2 in PD-L1 expression and in the progression of lung tumors. We found that EZH2 was upregulated in lung cancer tissues and positively correlated with PD-L1 levels and poor prognosis. Further, shRNA-expressing lentivirus mediated EZH2 knockdown suppressed both the mRNA and protein expression level of PD-L1, thus delaying lung cancer progression in vivo by enhancing anti-tumor immune responses. Moreover, the regulatory effect of EZH2 on PD-L1 depended on HIF-1α. The present results indicate that EZH2 regulates the immunosuppressive molecule PD-L1 expression via HIF-1α in non-small cell lung cancer cells.


Asunto(s)
Antígeno B7-H1/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Regulación Neoplásica de la Expresión Génica , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias Pulmonares/genética , Animales , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Femenino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Ratones Endogámicos C57BL
9.
Nanotechnology ; 30(32): 325203, 2019 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-30947153

RESUMEN

Integrated fabrics with a smart heating control system (HCS) are attractive in warming and thermotherapy for human healthcare management. Metal nanofibers (NFs) networks with high flexibility, conductivity and gas permeability are ideal functional materials for wearable electronics. Herein, a novel sandwich-structural (Ag NFs/fabrics/Pt NFs) textile for a HCS is constructed, where a Ag NF network film was functioned as a wearable heater and Pt NF network arrays were functioned as wearable temperature sensors. Conductivity and mechanical stability of the metal NFs were enhanced by crosslinking the free-standing fiber networks, resulting in high thermo-stability, thermal resistance (163.5 °C W-1 cm2) and temperature sensitivity (0.135% °C-1) of the HCS. The HCS can simultaneously realize heating and temperature distribution detection, demonstrating only 0.57% average error between the simulated resistance-to-temperature diagram of Pt NF arrays and actual temperature mapping. In addition, the HCS can be stuck on the skin for thermochromic fabrics, real-time heating and temperature detection/control through a Bluetooth device in a smartphone wirelessly.

10.
Small ; 14(45): e1803101, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30300473

RESUMEN

Theranostic materials are of great significance to a personalized precise medicine. However, conventional theranostic agents are mainly fabricated by combining presynthesized independent imaging probes and therapeutic agents, suffering from multiple synthesis procedures, poor morphological control, and time/reagent-consuming process. Herein, iodinated polypyrrole (I-PPy) nanoparticles are fabricated via a one-step synthesis strategy combining chemical oxidation and iodination for computed tomography (CT) imaging-guided photothermal therapy. Iodic acid with a high standard electrode potential enables the chemical oxidation polymerization of pyrrole monomers. Meanwhile, the iodination of PPy induced by the corresponding reduction product I2 takes place during the polymerization process to generate I-PPy nanoparticles. The prepared I-PPy nanoparticles possess a uniform size, excellent colloidal stability, intense near-infrared absorption, strong X-ray attenuation ability, and favorable biocompatibility. The as-synthesized I-PPy nanoparticles not only guarantee remarkable contrast-enhanced CT imaging of blood pool and tumors, but also realize effective tumor suppression in vitro and in vivo by I-PPy nanoparticles-mediated CT imaging-guided photothermal therapy. To the best of the authors' knowledge, it is the first time that multifunctional PPy nanoparticles are fabricated through a one-step synthesis process. The proposed strategy opens up a new way for the fabrication of high-performance theranostic agents via a one-step strategy under mild conditions.


Asunto(s)
Nanopartículas/química , Fototerapia/métodos , Polímeros/química , Pirroles/química , Animales , Halogenación , Humanos , Tomografía Computarizada por Rayos X
11.
Stem Cells ; 33(12): 3423-36, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26299367

RESUMEN

A novel hypothesis in cancer biology proposes that cancer growth is driven by cancer stem-like cells (CSLCs), also called tumor-initiating cells, which can self-renew and differentiate into multilineage progeny in a fashion similar to stem cells. However, the impact and underlying mechanisms of this process in lung adenocarcinoma (LAC) remain to be elucidated. Here, we report that microRNA-214 (miR-214) contributes to cell self-renewal by directly targeting catenin beta interacting protein 1 (CTNNBIP1), a member of the Wnt signaling pathway. We demonstrate that miR-214 overexpression enhances stem-like properties in LAC cells and that miR-214 shows increased expression in CSLCs derived from primary tumor tissue and from two LAC cell lines (A549 and NCI-H1650). Strikingly, downregulation of miR-214 expression in CSLCs resulted in a significant decrease in spheroid formation and the expression of the stem-cell markers Nanog, Oct-4, and Sox-2. Finally, CTNNBIP1 was identified as a target of miR-214. miR-214 expression in LAC was negatively correlated with CTNNBIP1 expression and positively correlated with differentiated cellular states. Moreover, CTNNBIP1 expression correlated with longer overall survival in LAC patients. This study reveals that miR-214 plays a critical role in CSLC self-renewal and stemness by targeting CTNNBIP1. The identification of this functional miR-214-CTNNBIP1 interaction that regulates self-renewal in CSLCs has the potential to direct the development of novel therapeutic strategies for LAC.


Asunto(s)
Adenocarcinoma/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias Pulmonares/metabolismo , MicroARNs/metabolismo , Proteínas de Neoplasias/metabolismo , Células Madre Neoplásicas/metabolismo , ARN Neoplásico/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Adenocarcinoma/genética , Adenocarcinoma/patología , Animales , Línea Celular Tumoral , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Ratones , Ratones SCID , MicroARNs/genética , Proteínas de Neoplasias/genética , Células Madre Neoplásicas/patología , ARN Neoplásico/genética
12.
Acta Biomater ; 179: 340-353, 2024 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-38556136

RESUMEN

Cellular senescence is a permanent state of cell cycle arrest characterized by increased activity of senescence associated ß-galactosidase (SA-ß-gal). Notably, cancer cells have been also observed to exhibit the senescence response and are being considered for sequential treatment with pro-senescence therapy followed by senolytic therapy. However, there is currently no effective agent targeting ß-galactosidase (ß-Gal) for imaging cellular senescence and monitoring senolysis in cancer therapy. Aggregation-induced emission luminogen (AIEgen) demonstrates strong fluorescence, good photostability, and biocompatibility, making it a potential candidate for imaging cellular senescence and monitoring senolysis in cancer therapy when endowed with ß-Gal-responsive capabilities. In this study, we introduced a ß-Gal-activated AIEgen named QM-ß-gal for cellular senescence imaging and senolysis monitoring in cancer therapy. QM-ß-gal exhibited good amphiphilic properties and formed aggregates that emitted a fluorescence signal upon ß-Gal activation. It showed high specificity towards the activity of ß-Gal in lysosomes and successfully visualized DOX-induced senescent cancer cells with intense fluorescence both in vitro and in vivo. Encouragingly, QM-ß-gal could image senescent cancer cells in vivo for over 14 days with excellent biocompatibility. Moreover, it allowed for the monitoring of senescent cancer cell clearance during senolytic therapy with ABT263. This investigation indicated the potential of the ß-Gal-activated AIEgen, QM-ß-gal, as an in vivo approach for imaging cellular senescence and monitoring senolysis in cancer therapy via highly specific and long-term fluorescence imaging. STATEMENT OF SIGNIFICANCE: This work reported a ß-galactosidase-activated AIEgen called QM-ß-gal, which effectively imaged DOX-induced senescent cancer cells both in vitro and in vivo. QM-ß-gal specifically targeted the increased expression and activity of ß-galactosidase in senescent cancer cells, localized within lysosomes. It was cleared rapidly before activation but maintained stability after activation in the DOX-induced senescent tumor. The AIEgen exhibited a remarkable long-term imaging capability for senescent cancer cells, lasting over 14 days and enabled monitoring of senescent cancer cell clearance through ABT263-induced apoptosis. This approach held promise for researchers seeking to achieve prolonged imaging of senescent cells in vivo.


Asunto(s)
Senescencia Celular , beta-Galactosidasa , Senescencia Celular/efectos de los fármacos , beta-Galactosidasa/metabolismo , Humanos , Animales , Neoplasias/diagnóstico por imagen , Neoplasias/patología , Neoplasias/tratamiento farmacológico , Línea Celular Tumoral , Ratones Desnudos , Ratones , Doxorrubicina/farmacología , Doxorrubicina/química , Imagen Óptica/métodos
13.
CNS Neurosci Ther ; 30(9): e70054, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39306799

RESUMEN

OBJECTIVES: This study aims to elucidate the role of Fe2+ overload in kainic acid (KA)-induced excitotoxicity, investigate the involvement of ferritinophagy selective cargo receptor NCOA4 in the pathogenesis of excitotoxicity. METHODS: Western blotting was used to detect the expression of FTH1, NCOA4, Lamp2, TfR, FPN, and DMT1 after KA stereotaxic injection into the unilateral striatum of mice. Colocalization of Fe2+ with lysosomes in KA-treated primary cortical neurons was observed by using confocal microscopy. Desferrioxamine (DFO) was added to chelate free iron, a CCK8 kit was used to measure cell viability, and the Fe2+ levels were detected by FerroOrange. BODIPY C11 was used to determine intracellular lipid reactive oxygen species (ROS) levels, and the mRNA levels of PTGS2, a biomarker of ferroptosis, were measured by fluorescent quantitative PCR. 3-Methyladenine (3-MA) was employed to inhibit KA-induced activation of autophagy, and changes in ferritinophagy-related protein expression and the indicated biomarkers of ferroptosis were detected. Endogenous NCOA4 was knocked down by lentivirus transfection, and cell viability and intracellular Fe2+ levels were observed after KA treatment. RESULTS: Western blot results showed that the expression of NCOA4, DMT1, and Lamp2 was significantly upregulated, while FTH1 was downregulated, but there were no significant changes in TfR and FPN. The fluorescence results indicated that KA enhanced the colocalization of free Fe2+ with lysosomes in neurons. DFO intervention could effectively rescue cell damage, reduce intracellular lipid peroxidation, and decrease the increased transcript levels of PTGS2 caused by KA. Pretreatment with 3-MA effectively reversed KA-induced ferritinophagy and ferroptosis. Endogenous interference with NCOA4 significantly improved cell viability and reduced intracellular free Fe2+ levels in KA-treated cells. CONCLUSION: KA-induced excitotoxicity activates ferritinophagy, and targeting ferritinophagy effectively inhibits downstream ferroptosis. Interference with NCOA4 effectively attenuates KA-induced neuronal damage. This study provides a potential therapeutic target for excitotoxicity related disease conditions.


Asunto(s)
Ferritinas , Ferroptosis , Neuronas , Coactivadores de Receptor Nuclear , Animales , Ferroptosis/efectos de los fármacos , Ferroptosis/fisiología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Ratones , Ferritinas/metabolismo , Coactivadores de Receptor Nuclear/metabolismo , Coactivadores de Receptor Nuclear/genética , Autofagia/efectos de los fármacos , Autofagia/fisiología , Ratones Endogámicos C57BL , Masculino , Receptores de Transferrina/metabolismo , Receptores de Transferrina/genética , Especies Reactivas de Oxígeno/metabolismo , Células Cultivadas , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Hierro/metabolismo , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Proteína 2 de la Membrana Asociada a los Lisosomas/metabolismo , Proteína 2 de la Membrana Asociada a los Lisosomas/genética , Sistema de Transporte de Aminoácidos y+ , Proteínas de Transporte de Catión
14.
CNS Neurosci Ther ; 30(7): e14860, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39014268

RESUMEN

OBJECTIVE: Alzheimer's disease (AD) pathology is featured by the extracellular accumulation of amyloid-ß (Aß) plaques and intracellular tau neurofibrillary tangles in the brain. We studied whether Aß and tau accumulation are independently associated with future cognitive decline in the AD continuum. METHODS: Data were acquired from the Alzheimer's Disease Neuroimaging Initiative (ADNI) public database. A total of 1272 participants were selected based on the availability of Aß-PET and CSF tau at baseline and of those 777 participants with follow-up visits. RESULTS: We found that Aß-PET and CSF tau pathology were related to cognitive decline across the AD clinical spectrum, both as potential predictors for dementia progression. Among them, Aß-PET (A + T- subjects) is an independent reliable predictor of longitudinal cognitive decline in terms of ADAS-13, ADNI-MEM, and MMSE scores rather than tau pathology (A - T+ subjects), indicating tau accumulation is not closely correlated with future cognitive impairment without being driven by Aß deposition. Of note, a high percentage of APOE ε4 carriers with Aß pathology (A+) develop poor memory and learning capacity. Interestingly, this condition is not recurrence in terms of the ADNI-MEM domain when adding APOE ε4 status. Finally, the levels of Aß-PET SUVR related to glucose hypometabolism more strongly in subjects with A + T- than A - T+ both happen at baseline and longitudinal changes. CONCLUSIONS: In conclusion, Aß-PET alone without tau pathology (A + T-) measure is an independent reliable predictor of longitudinal cognitive decline but may nonetheless forecast different status of dementia progression. However, tau accumulation alone without Aß pathology background (A - T+) was not enough to be an independent predictor of cognitive worsening.


Asunto(s)
Péptidos beta-Amiloides , Disfunción Cognitiva , Tomografía de Emisión de Positrones , Proteínas tau , Humanos , Proteínas tau/metabolismo , Femenino , Masculino , Péptidos beta-Amiloides/metabolismo , Anciano , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/patología , Tomografía de Emisión de Positrones/tendencias , Estudios Longitudinales , Anciano de 80 o más Años , Progresión de la Enfermedad , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/psicología , Persona de Mediana Edad
16.
Redox Biol ; 73: 103176, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38705094

RESUMEN

Excitotoxicity is a prevalent pathological event in neurodegenerative diseases. The involvement of ferroptosis in the pathogenesis of excitotoxicity remains elusive. Transcriptome analysis has revealed that cytoplasmic reduced nicotinamide adenine dinucleotide phosphate (NADPH) levels are associated with susceptibility to ferroptosis-inducing compounds. Here we show that exogenous NADPH, besides being reductant, interacts with N-myristoyltransferase 2 (NMT2) and upregulates the N-myristoylated ferroptosis suppressor protein 1 (FSP1). NADPH increases membrane-localized FSP1 and strengthens resistance to ferroptosis. Arg-291 of NMT2 is critical for the NADPH-NMT2-FSP1 axis-mediated suppression of ferroptosis. This study suggests that NMT2 plays a pivotal role by bridging NADPH levels and neuronal susceptibility to ferroptosis. We propose a mechanism by which the NADPH regulates N-myristoylation, which has important implications for ferroptosis and disease treatment.


Asunto(s)
Ferroptosis , NADP , Humanos , NADP/metabolismo , Animales , Aciltransferasas/metabolismo , Aciltransferasas/genética , Ratones , Procesamiento Proteico-Postraduccional
17.
Chem Sci ; 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39184302

RESUMEN

Developing exciplex-based organic long-persistent luminescence (OLPL) materials with high stability is very important but remains a formidable challenge in a single-component system. Here, we report a facile strategy to achieve highly stable OLPL in an amorphous exciplex copolymer system via through-space charge transfer (TSCT). The copolymer composed of electron donor and acceptor units can not only exhibit effective TSCT for intra/intermolecular exciplex emission but also construct a rigid environment to isolate oxygen and suppress non-radiative decay, thereby enabling stable exciplex-based OLPL emission with color-tunable feature for more than 100 h under ambient conditions. These single-component OLPL copolymers demonstrate robust antibacterial activity against Escherichia coli under visible light irradiation. These results provide a solid example to exploit highly stable exciplex-based OLPL in polymers, shedding light on how the TSCT mechanism may potentially contribute to OLPL in a single-component molecular system and broadening the scope of OLPL applications.

18.
Cell Death Dis ; 15(10): 744, 2024 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-39394148

RESUMEN

Extensive studies indicate that mitochondria dysfunction is pivotal for Alzheimer's disease (AD) pathogenesis; while cumulative evidence suggests that increased mitochondrial stress response (MSR) may mitigate neurodegeneration in AD, explorations to develop a MSR-targeted therapeutic strategy against AD are scarce. We combined cell biology, molecular biology, and pharmacological approaches to unravel a novel molecular pathway by which NAD+-boosting agent nicotinamide mononucleotide (NMN) regulates MSR in AD models. Here, we report dyshomeostasis plasma UPRmt-mitophagy-mediated MSR profiles in AD patient samples. NMN restores NAD+ metabolic profiles and improves MSR through the ATF4-dependent UPRmt pathway in AD-related cross-species models. At the organismal level, NAD+ repletion with NMN supplementation ameliorates mitochondrial proteotoxicity, decreases hippocampal synaptic disruption, decreases neuronal loss, and brain atrophy in mice model of AD. Remarkably, omics features of the hippocampus with NMN show that NMN leads to transcriptional changes of genes and proteins involved in MSR characteristics, principally within the astrocyte unit rather than microglia and oligodendrocytes. In brief, our work provides evidence that MSR has an active role in the pathogenesis of AD, as reducing mitochondrial homeostasis via atf4 depletion in AD mice aggravates the hallmarks of the disease; conversely, bolstering mitochondrial proteostasis by NMN decreases protein aggregation, restores memory performance, and delays disease progression, ultimately translating to increased healthspan.


Asunto(s)
Factor de Transcripción Activador 4 , Enfermedad de Alzheimer , Mitocondrias , NAD , Mononucleótido de Nicotinamida , Respuesta de Proteína Desplegada , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Animales , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Factor de Transcripción Activador 4/metabolismo , Humanos , Ratones , Mononucleótido de Nicotinamida/farmacología , NAD/metabolismo , Respuesta de Proteína Desplegada/efectos de los fármacos , Modelos Animales de Enfermedad , Hipocampo/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/patología , Masculino , Ratones Endogámicos C57BL
19.
EBioMedicine ; 108: 105333, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39321500

RESUMEN

BACKGROUND: While many patients seem to recover from SARS-CoV-2 infections, many patients report experiencing SARS-CoV-2 symptoms for weeks or months after their acute COVID-19 ends, even developing new symptoms weeks after infection. These long-term effects are called post-acute sequelae of SARS-CoV-2 (PASC) or, more commonly, Long COVID. The overall prevalence of Long COVID is currently unknown, and tools are needed to help identify patients at risk for developing long COVID. METHODS: A working group of the Rapid Acceleration of Diagnostics-radical (RADx-rad) program, comprised of individuals from various NIH institutes and centers, in collaboration with REsearching COVID to Enhance Recovery (RECOVER) developed and organized the Long COVID Computational Challenge (L3C), a community challenge aimed at incentivizing the broader scientific community to develop interpretable and accurate methods for identifying patients at risk of developing Long COVID. From August 2022 to December 2022, participants developed Long COVID risk prediction algorithms using the National COVID Cohort Collaborative (N3C) data enclave, a harmonized data repository from over 75 healthcare institutions from across the United States (U.S.). FINDINGS: Over the course of the challenge, 74 teams designed and built 35 Long COVID prediction models using the N3C data enclave. The top 10 teams all scored above a 0.80 Area Under the Receiver Operator Curve (AUROC) with the highest scoring model achieving a mean AUROC of 0.895. Included in the top submission was a visualization dashboard that built timelines for each patient, updating the risk of a patient developing Long COVID in response to clinical events. INTERPRETATION: As a result of L3C, federal reviewers identified multiple machine learning models that can be used to identify patients at risk for developing Long COVID. Many of the teams used approaches in their submissions which can be applied to future clinical prediction questions. FUNDING: Research reported in this RADx® Rad publication was supported by the National Institutes of Health. Timothy Bergquist, Johanna Loomba, and Emily Pfaff were supported by Axle Subcontract: NCATS-STSS-P00438.


Asunto(s)
COVID-19 , Aprendizaje Automático , SARS-CoV-2 , Humanos , COVID-19/epidemiología , SARS-CoV-2/aislamiento & purificación , Estados Unidos/epidemiología , Algoritmos , Síndrome Post Agudo de COVID-19 , Estudios de Cohortes , Colaboración de las Masas
20.
J Mol Cell Biol ; 15(1)2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36792067

RESUMEN

Pterygium is a common ocular disease with a high recurrence rate, characterized by hyperplasia of subconjunctival fibrovascular tissue. Autophagy, an important process to maintain cellular homeostasis, participates in the pathogenic fibrosis of different organs. However, the exact role of autophagy in pterygium pathogenesis remains unknown. Here, we found that autophagic activity was decreased in human pterygium tissues compared with adjacent normal conjunctival tissues. The in vitro model of fibrosis was successfully established using human primary conjunctival fibroblasts (ConFB) treated with transforming growth factor-ß1 (TGF-ß1), evidenced by increased fibrotic level and strong proliferative and invasive capabilities. The autophagic activity was suppressed during TGF-ß1- or ultraviolet-induced fibrosis of ConFB. Activating autophagy dramatically retarded the fibrotic progress of ConFB, while blocking autophagy exacerbated this process. Furthermore, SQSTM1, the main cargo receptor of selective autophagy, was found to significantly promote the fibrosis of ConFB through activating the PKCι-NF-κB signaling pathway. Knockdown of SQSTM1, PKCι, or p65 in ConFB delayed TGF-ß1-induced fibrosis. Overexpression of SQSTM1 drastically abrogated the inhibitory effect of rapamycin or serum starvation on TGF-ß1-induced fibrosis. Collectively, our data suggested that autophagy impairment of human ConFB facilitates fibrosis via activating the SQSTM1-PKCι-NF-κB signaling cascades. This work was contributory to elucidating the mechanism of autophagy underlying pterygium occurrence.


Asunto(s)
FN-kappa B , Pterigion , Humanos , FN-kappa B/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Pterigion/patología , Proteína Sequestosoma-1/metabolismo , Transducción de Señal , Fibrosis , Autofagia
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