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1.
Cell ; 186(19): 4216-4234.e33, 2023 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-37714135

RESUMEN

Chronic stimulation can cause T cell dysfunction and limit the efficacy of cellular immunotherapies. Improved methods are required to compare large numbers of synthetic knockin (KI) sequences to reprogram cell functions. Here, we developed modular pooled KI screening (ModPoKI), an adaptable platform for modular construction of DNA KI libraries using barcoded multicistronic adaptors. We built two ModPoKI libraries of 100 transcription factors (TFs) and 129 natural and synthetic surface receptors (SRs). Over 30 ModPoKI screens across human TCR- and CAR-T cells in diverse conditions identified a transcription factor AP4 (TFAP4) construct that enhanced fitness of chronically stimulated CAR-T cells and anti-cancer function in vitro and in vivo. ModPoKI's modularity allowed us to generate an ∼10,000-member library of TF combinations. Non-viral KI of a combined BATF-TFAP4 polycistronic construct enhanced fitness. Overexpressed BATF and TFAP4 co-occupy and regulate key gene targets to reprogram T cell function. ModPoKI facilitates the discovery of complex gene constructs to program cellular functions.


Asunto(s)
Tratamiento Basado en Trasplante de Células y Tejidos , Ejercicio Físico , Humanos , Biblioteca de Genes , Inmunoterapia , Investigación
2.
Nature ; 625(7996): 805-812, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38093011

RESUMEN

CRISPR-enabled screening is a powerful tool for the discovery of genes that control T cell function and has nominated candidate targets for immunotherapies1-6. However, new approaches are required to probe specific nucleotide sequences within key genes. Systematic mutagenesis in primary human T cells could reveal alleles that tune specific phenotypes. DNA base editors are powerful tools for introducing targeted mutations with high efficiency7,8. Here we develop a large-scale base-editing mutagenesis platform with the goal of pinpointing nucleotides that encode amino acid residues that tune primary human T cell activation responses. We generated a library of around 117,000 single guide RNA molecules targeting base editors to protein-coding sites across 385 genes implicated in T cell function and systematically identified protein domains and specific amino acid residues that regulate T cell activation and cytokine production. We found a broad spectrum of alleles with variants encoding critical residues in proteins including PIK3CD, VAV1, LCP2, PLCG1 and DGKZ, including both gain-of-function and loss-of-function mutations. We validated the functional effects of many alleles and further demonstrated that base-editing hits could positively and negatively tune T cell cytotoxic function. Finally, higher-resolution screening using a base editor with relaxed protospacer-adjacent motif requirements9 (NG versus NGG) revealed specific structural domains and protein-protein interaction sites that can be targeted to tune T cell functions. Base-editing screens in primary immune cells thus provide biochemical insights with the potential to accelerate immunotherapy design.


Asunto(s)
Alelos , Edición Génica , Mutagénesis , Linfocitos T , Humanos , Aminoácidos/genética , Sistemas CRISPR-Cas/genética , Mutagénesis/genética , ARN Guía de Sistemas CRISPR-Cas/genética , Linfocitos T/inmunología , Linfocitos T/metabolismo , Activación de Linfocitos , Citocinas/biosíntesis , Citocinas/metabolismo , Mutación con Ganancia de Función , Mutación con Pérdida de Función
3.
Nature ; 609(7925): 174-182, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36002574

RESUMEN

The efficacy of adoptive T cell therapies for cancer treatment can be limited by suppressive signals from both extrinsic factors and intrinsic inhibitory checkpoints1,2. Targeted gene editing has the potential to overcome these limitations and enhance T cell therapeutic function3-10. Here we performed multiple genome-wide CRISPR knock-out screens under different immunosuppressive conditions to identify genes that can be targeted to prevent T cell dysfunction. These screens converged on RASA2, a RAS GTPase-activating protein (RasGAP) that we identify as a signalling checkpoint in human T cells, which is downregulated upon acute T cell receptor stimulation and can increase gradually with chronic antigen exposure. RASA2 ablation enhanced MAPK signalling and chimeric antigen receptor (CAR) T cell cytolytic activity in response to target antigen. Repeated tumour antigen stimulations in vitro revealed that RASA2-deficient T cells show increased activation, cytokine production and metabolic activity compared with control cells, and show a marked advantage in persistent cancer cell killing. RASA2-knockout CAR T cells had a competitive fitness advantage over control cells in the bone marrow in a mouse model of leukaemia. Ablation of RASA2 in multiple preclinical models of T cell receptor and CAR T cell therapies prolonged survival in mice xenografted with either liquid or solid tumours. Together, our findings highlight RASA2 as a promising target to enhance both persistence and effector function in T cell therapies for cancer treatment.


Asunto(s)
Antígenos de Neoplasias , Neoplasias , Linfocitos T , Proteínas Activadoras de ras GTPasa , Animales , Antígenos de Neoplasias/inmunología , Médula Ósea , Sistemas CRISPR-Cas , Modelos Animales de Enfermedad , Técnicas de Silenciamiento del Gen , Humanos , Inmunoterapia Adoptiva , Leucemia/inmunología , Leucemia/patología , Leucemia/terapia , Ratones , Neoplasias/inmunología , Neoplasias/patología , Neoplasias/terapia , Receptores de Antígenos de Linfocitos T/inmunología , Receptores Quiméricos de Antígenos/inmunología , Linfocitos T/inmunología , Linfocitos T/metabolismo , Factores de Tiempo , Ensayos Antitumor por Modelo de Xenoinjerto , Proteínas Activadoras de ras GTPasa/deficiencia , Proteínas Activadoras de ras GTPasa/genética
4.
Nature ; 579(7798): 270-273, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32015507

RESUMEN

Since the outbreak of severe acute respiratory syndrome (SARS) 18 years ago, a large number of SARS-related coronaviruses (SARSr-CoVs) have been discovered in their natural reservoir host, bats1-4. Previous studies have shown that some bat SARSr-CoVs have the potential to infect humans5-7. Here we report the identification and characterization of a new coronavirus (2019-nCoV), which caused an epidemic of acute respiratory syndrome in humans in Wuhan, China. The epidemic, which started on 12 December 2019, had caused 2,794 laboratory-confirmed infections including 80 deaths by 26 January 2020. Full-length genome sequences were obtained from five patients at an early stage of the outbreak. The sequences are almost identical and share 79.6% sequence identity to SARS-CoV. Furthermore, we show that 2019-nCoV is 96% identical at the whole-genome level to a bat coronavirus. Pairwise protein sequence analysis of seven conserved non-structural proteins domains show that this virus belongs to the species of SARSr-CoV. In addition, 2019-nCoV virus isolated from the bronchoalveolar lavage fluid of a critically ill patient could be neutralized by sera from several patients. Notably, we confirmed that 2019-nCoV uses the same cell entry receptor-angiotensin converting enzyme II (ACE2)-as SARS-CoV.


Asunto(s)
Betacoronavirus/clasificación , Betacoronavirus/genética , Quirópteros/virología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Brotes de Enfermedades , Neumonía Viral/epidemiología , Neumonía Viral/virología , Enzima Convertidora de Angiotensina 2 , Animales , Anticuerpos Antivirales/sangre , Betacoronavirus/metabolismo , Betacoronavirus/ultraestructura , COVID-19 , Línea Celular , China/epidemiología , Chlorocebus aethiops , Femenino , Genoma Viral/genética , Humanos , Masculino , Peptidil-Dipeptidasa A/metabolismo , Filogenia , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/clasificación , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética , SARS-CoV-2 , Homología de Secuencia de Ácido Nucleico , Síndrome Respiratorio Agudo Grave , Células Vero
5.
Proc Natl Acad Sci U S A ; 120(24): e2219649120, 2023 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-37276408

RESUMEN

How left-right (LR) asymmetry emerges in a patterning field along the anterior-posterior axis remains an unresolved problem in developmental biology. Left-biased Nodal emanating from the LR organizer propagates from posterior to anterior (PA) and establishes the LR pattern of the whole embryo. However, little is known about the regulatory mechanism of the PA spread of Nodal and its asymmetric activation in the forebrain. Here, we identify bilaterally expressed Follistatin (Fst) as a regulator blocking the propagation of the zebrafish Nodal ortholog Southpaw (Spaw) in the right lateral plate mesoderm (LPM), and restricting Spaw transmission in the left LPM to facilitate the establishment of a robust LR asymmetric Nodal patterning. In addition, Fst inhibits the Activin-Nodal signaling pathway in the forebrain thus preventing Nodal activation prior to the arrival, at a later time, of Spaw emanating from the left LPM. This contributes to the orderly propagation of asymmetric Nodal activation along the PA axis. The LR regulation function of Fst is further confirmed in chick and frog embryos. Overall, our results suggest that a robust LR patterning emerges by counteracting a Fst barrier formed along the PA axis.


Asunto(s)
Proteínas de Pez Cebra , Pez Cebra , Animales , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Folistatina/genética , Folistatina/metabolismo , Tipificación del Cuerpo/genética , Factor de Crecimiento Transformador beta/metabolismo , Regulación del Desarrollo de la Expresión Génica
6.
Bioinformatics ; 40(3)2024 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-38449285

RESUMEN

MOTIVATION: Drug-target interaction (DTI) prediction aims to identify interactions between drugs and protein targets. Deep learning can automatically learn discriminative features from drug and protein target representations for DTI prediction, but challenges remain, making it an open question. Existing approaches encode drugs and targets into features using deep learning models, but they often lack explanations for underlying interactions. Moreover, limited labeled DTIs in the chemical space can hinder model generalization. RESULTS: We propose an interpretable nested graph neural network for DTI prediction (iNGNN-DTI) using pre-trained molecule and protein models. The analysis is conducted on graph data representing drugs and targets by using a specific type of nested graph neural network, in which the target graphs are created based on 3D structures using Alphafold2. This architecture is highly expressive in capturing substructures of the graph data. We use a cross-attention module to capture interaction information between the substructures of drugs and targets. To improve feature representations, we integrate features learned by models that are pre-trained on large unlabeled small molecule and protein datasets, respectively. We evaluate our model on three benchmark datasets, and it shows a consistent improvement on all baseline models in all datasets. We also run an experiment with previously unseen drugs or targets in the test set, and our model outperforms all of the baselines. Furthermore, the iNGNN-DTI can provide more insights into the interaction by visualizing the weights learned by the cross-attention module. AVAILABILITY AND IMPLEMENTATION: The source code of the algorithm is available at https://github.com/syan1992/iNGNN-DTI.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Interacciones Farmacológicas , Benchmarking , Sistemas de Liberación de Medicamentos
7.
PLoS Pathog ; 19(10): e1011742, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37871014

RESUMEN

Viral infection triggers the activation of transcription factor IRF3, and its activity is precisely regulated for robust antiviral immune response and effective pathogen clearance. However, how full activation of IRF3 is achieved has not been well defined. Herein, we identified BLK as a key kinase that positively modulates IRF3-dependent signaling cascades and executes a pre-eminent antiviral effect. BLK deficiency attenuates RNA or DNA virus-induced ISRE activation, interferon production and the cellular antiviral response in human and murine cells, whereas overexpression of BLK has the opposite effects. BLK-deficient mice exhibit lower serum cytokine levels and higher lethality after VSV infection. Moreover, BLK deficiency impairs the secretion of downstream antiviral cytokines and promotes Senecavirus A (SVA) proliferation, thereby supporting SVA-induced oncolysis in an in vivo xenograft tumor model. Mechanistically, viral infection triggers BLK autophosphorylation at tyrosine 309. Subsequently, activated BLK directly binds and phosphorylates IRF3 at tyrosine 107, which further promotes TBK1-induced IRF3 S386 and S396 phosphorylation, facilitating sufficient IRF3 activation and downstream antiviral response. Collectively, our findings suggest that targeting BLK enhances viral clearance via specifically regulating IRF3 phosphorylation by a previously undefined mechanism.


Asunto(s)
Proteínas Serina-Treonina Quinasas , Virosis , Humanos , Animales , Ratones , Fosforilación , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Factor 3 Regulador del Interferón/metabolismo , Procesamiento Proteico-Postraduccional , Citocinas/metabolismo , Inmunidad Innata , Familia-src Quinasas/metabolismo
8.
FASEB J ; 38(13): e23743, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38877852

RESUMEN

Kisspeptin signaling regulates energy homeostasis. Adiposity is the principal source and receiver of peripheral Kisspeptin, and adipose Kiss1 metastasis suppressor (Kiss1) gene expression is stimulated by exercise. However, whether the adipose Kiss1 gene regulates energy homeostasis and plays a role in adaptive alterations during prolonged exercise remains unknown. Here, we investigated the role of Kiss1 role in mice and adipose tissues and the adaptive changes it induces after exercise, using adipose-specific Kiss1 knockout (Kiss1adipoq-/-) and adeno-associated virus-induced adipose tissue Kiss1-overexpressing (Kiss1adipoq over) mice. We found that adipose-derived kisspeptin signal regulates lipid and glucose homeostasis to maintain systemic energy homeostasis, but in a sex-dependent manner, with more pronounced metabolic changes in female mice. Kiss1 regulated adaptive alterations of genes and proteins in tricarboxylic acid (TCA) cycle and oxidative phosphorylation (OxPhos) pathways in female gWAT following prolonged aerobic exercise. We could further show that adipose Kiss1 deficiency leads to reduced peroxisome proliferator-activated receptor gamma co-activator 1 alpha (PGC-1α) protein content of soleus muscle and maximum oxygen uptake (VO2 max) of female mice after prolonged exercise. Therefore, adipose Kisspeptin may be a novel adipokine that increases organ sensitivity to glucose, lipids, and oxygen following exercise.


Asunto(s)
Tejido Adiposo , Metabolismo Energético , Homeostasis , Kisspeptinas , Ratones Noqueados , Condicionamiento Físico Animal , Animales , Kisspeptinas/metabolismo , Kisspeptinas/genética , Femenino , Ratones , Condicionamiento Físico Animal/fisiología , Masculino , Tejido Adiposo/metabolismo , Ratones Endogámicos C57BL , Adaptación Fisiológica
9.
PLoS Biol ; 20(11): e3001856, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36318514

RESUMEN

Feingold syndrome type 1, caused by loss-of-function of MYCN, is characterized by varied phenotypes including esophageal and duodenal atresia. However, no adequate model exists for studying the syndrome's pathological or molecular mechanisms, nor is there a treatment strategy. Here, we developed a zebrafish Feingold syndrome type 1 model with nonfunctional mycn, which had severe intestinal atresia. Single-cell RNA-seq identified a subcluster of intestinal cells that were highly sensitive to Mycn, and impaired cell proliferation decreased the overall number of intestinal cells in the mycn mutant fish. Bulk RNA-seq and metabolomic analysis showed that expression of ribosomal genes was down-regulated and that amino acid metabolism was abnormal. Northern blot and ribosomal profiling analysis showed abnormal rRNA processing and decreases in free 40S, 60S, and 80S ribosome particles, which led to impaired translation in the mutant. Besides, both Ribo-seq and western blot analysis showed that mTOR pathway was impaired in mycn mutant, and blocking mTOR pathway by rapamycin treatment can mimic the intestinal defect, and both L-leucine and Rheb, which can elevate translation via activating TOR pathway, could rescue the intestinal phenotype of mycn mutant. In summary, by this zebrafish Feingold syndrome type 1 model, we found that disturbance of ribosomal biogenesis and blockage of protein synthesis during development are primary causes of the intestinal defect in Feingold syndrome type 1. Importantly, our work suggests that leucine supplementation may be a feasible and easy treatment option for this disease.


Asunto(s)
Microcefalia , Pez Cebra , Animales , Proteína Proto-Oncogénica N-Myc , Pez Cebra/metabolismo , Microcefalia/genética , Serina-Treonina Quinasas TOR/metabolismo , Leucina
10.
Crit Rev Immunol ; 44(4): 1-12, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38505917

RESUMEN

Stroke remained the leading cause of disability in the world, and the most important non-modifiable risk factor was age. The treatment of stroke for elder patients faced multiple difficulties due to its complicated pathogenesis and mechanism. Therefore, we aimed to identify the potential differentially expressed genes (DEGs) and singnalling pathways for aged people of stroke. To compare the DEGs in the aged rats with or without middle cerebral artery occlusion (MCAO) and to analyse the important genes and the key signaling pathways involved in the development of cerebral ischaemia in aged rats. The Gene Expression Omnibus (GEO) analysis tool was used to analyse the DEGs in the GSE166162 dataset of aged MCAO rats compared with aged sham rats. Differential expression analysis was performed in aged MCAO rats and sham rats using limma. In addition, the 74 DEGs (such as Fam111a, Lcn2, Spp1, Lgals3 and Gpnmb were up-regulated; Egr2, Nr4a3, Arc, Klf4 and Nr4a1 were down-regulated) and potential compounds corresponding to the top 20 core genes in the Protein-Protein Interaction (PPI) network was constructed using the STRING database (version 12.0). Among these 30 compounds, resveratrol, cannabidiol, honokiol, fucoxanthin, oleandrin and tyrosol were significantly enriched. These DEGs were subjected to Gene Ontology (GO) function analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis to determine the most significantly enriched pathway in aged MCAO rats. Moreover, innate immune response, the complement and coagulation cascades signaling pathway, the IL-17 and other signaling pathways were significantly correlated with the aged MCAO rats. Our study indicates that multiple genes and pathological processes involved in the aged people of stroke. The immune response might be the key pathway in the intervention of cerebral infarction in aged people.


Asunto(s)
Infarto de la Arteria Cerebral Media , Accidente Cerebrovascular , Ratas , Humanos , Animales , Anciano , Infarto de la Arteria Cerebral Media/genética , Infarto de la Arteria Cerebral Media/metabolismo , Perfilación de la Expresión Génica , Resveratrol , Expresión Génica , Glicoproteínas de Membrana/genética
11.
Eur Heart J ; 45(25): 2235-2250, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38607560

RESUMEN

BACKGROUND AND AIMS: Patients with acute myeloid leukaemia (AML) suffer from severe myocardial injury during daunorubicin (DNR)-based chemotherapy and are at high risk of cardiac mortality. The crosstalk between tumour cells and cardiomyocytes might play an important role in chemotherapy-related cardiotoxicity, but this has yet to be demonstrated. This study aimed to identify its underlying mechanism and explore potential therapeutic targets. METHODS: Cardiac tissues were harvested from an AML patient after DNR-based chemotherapy and were subjected to single-nucleus RNA sequencing. Cardiac metabolism and function were evaluated in AML mice after DNR treatment by using positron emission tomography, magnetic resonance imaging, and stable-isotope tracing metabolomics. Plasma cytokines were screened in AML mice after DNR treatment. Genetically modified mice and cell lines were used to validate the central role of the identified cytokine and explore its downstream effectors. RESULTS: In the AML patient, disruption of cardiac metabolic homeostasis was associated with heart dysfunction after DNR-based chemotherapy. In AML mice, cardiac fatty acid utilization was attenuated, resulting in cardiac dysfunction after DNR treatment, but these phenotypes were not observed in similarly treated tumour-free mice. Furthermore, tumour cell-derived interleukin (IL)-1α was identified as a primary factor leading to DNR-induced cardiac dysfunction and administration of an anti-IL-1α neutralizing antibody could improve cardiac functions in AML mice after DNR treatment. CONCLUSIONS: This study revealed that crosstalk between tumour cells and cardiomyocytes during chemotherapy could disturb cardiac energy metabolism and impair heart function. IL-1α neutralizing antibody treatment is a promising strategy for alleviating chemotherapy-induced cardiotoxicity in AML patients.


Asunto(s)
Daunorrubicina , Interleucina-1alfa , Leucemia Mieloide Aguda , Animales , Leucemia Mieloide Aguda/tratamiento farmacológico , Humanos , Interleucina-1alfa/metabolismo , Ratones , Cardiotoxicidad/etiología , Antibióticos Antineoplásicos/efectos adversos , Masculino , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo
12.
Nano Lett ; 24(17): 5197-5205, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38634879

RESUMEN

Highly active nonprecious-metal single-atom catalysts (SACs) toward catalytic transfer hydrogenation (CTH) of α,ß-unsaturated aldehydes are of great significance but still are deficient. Herein, we report that Zn-N-C SACs containing Zn-N3 moieties can catalyze the conversion of cinnamaldehyde to cinnamyl alcohol with a conversion of 95.5% and selectivity of 95.4% under a mild temperature and atmospheric pressure, which is the first case of Zn-species-based heterogeneous catalysts for the CTH reaction. Isotopic labeling, in situ FT-IR spectroscopy, and DFT calculations indicate that reactants, coabsorbed at the Zn sites, proceed CTH via a "Meerwein-Ponndorf-Verley" mechanism. DFT calculations also reveal that the high activity over Zn-N3 moieties stems from the suitable adsorption energy and favorable reaction energy of the rate-determining step at the Zn active sites. Our findings demonstrate that Zn-N-C SACs hold extraordinary activity toward CTH reactions and thus provide a promising approach to explore the advanced SACs for high-value-added chemicals.

13.
Small ; 20(30): e2307482, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38412428

RESUMEN

Manganese-based oxides (MnOx) suffer from sluggish charge diffusion kinetics and poor cycling stability in sodium ion storage. Herein, an interfacial electric field (IEF) in CeO2/MnOx is constructed to obtain high electronic/ionic conductivity and structural stability of MnOx. The as-designed CeO2/MnOx exhibits a remarkable capacity of 397 F g-1 and favorable cyclic stability with 92.13% capacity retention after 10,000 cycles. Soft X-ray absorption spectroscopy and partial density of states results reveal that the electrons are substantially injected into the Mn t2g orbitals driven by the formed IEF. Correspondingly, the MnO6 units in MnOx are effectively activated, endowing the CeO2/MnOx with fast charge transfer kinetics and high sodium ion storage capacity. Moreover, In situRaman verifies a remarkably increased structural stability of CeO2/MnOx, which is attributed to the enhanced Mn─O bond strength and efficiently stabilized MnO6 units. Mechanism studies show that the downshift of Mn 3d-band center dramatically increases the Mn 3d-O 2p orbitals overlap, thus inhibiting the Jahn-Teller (J-T) distortion of MnOx during sodium ion insertion/extraction. This work develops an advanced strategy to achieve both fast and sustainable sodium ion storage in metal oxides-based energy materials.

14.
Small ; 20(27): e2311124, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38258393

RESUMEN

The electrochemical nitrogen oxidation reaction (NOR) holds significant potential to revolutionize the traditional nitrate synthesis processes. However, the progression in NOR has been notably stymied due to the sluggish kinetics of initial N2 adsorption and activation processes. Herein, the research embarks on the development of a CeO2-Co3O4 heterostructure, strategically engineered to facilitate the electron transfer from CeO2 to Co3O4. This orchestrated transfer operates to amplify the d-band center of the Co active sites, thereby enhancing N2 adsorption and activation dynamics by strengthening the Co─N bond and diminishing the resilience of the N≡N bond. The synthesized CeO2-Co3O4 manifests promising prospects, showcasing a significant HNO3 yield of 37.96 µg h-1 mgcat -1 and an elevated Faradaic efficiency (FE) of 29.30% in a 0.1 m Na2SO4 solution at 1.81 V versus RHE. Further substantiating these findings, an array of in situ methodologies coupled with DFT calculations vividly illustrate the augmented adsorption and activation of N2 on the surface of CeO2-Co3O4 heterostructure, resulting in a substantial reduction in the energy barrier pertinent to the rate-determining step within the NOR pathway. This research carves a promising pathway to amplify N2 adsorption throughout the electrochemical NOR operations and delineates a blueprint for crafting highly efficient NOR electrocatalysts.

15.
Am Heart J ; 269: 131-138, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38128898

RESUMEN

BACKGROUND: Nearly 20% Patients with cyanotic congenital heart disease (CCHD) are not able to receive surgery. These patients experience a decline in cardiac function as they age, which has been demonstrated to be associated with changes in energy metabolism in cardiomyocytes. Trimetazidine (TMZ), a metabolic regulator, is supposed to alleviate such maladaptation and reserve cardiac function in CCHD patients. METHODS: This is a randomized, double-blind, placebo-controlled clinical trial. Eighty adult CCHD patients will be recruited and randomized to the TMZ (20 mg TMZ 3 times a day for 3 months) or placebo group (placebo 3 times a day for 3 months). The primary outcome is the difference in cardiac ejection fractions (EF) measured by cardiac magnetic resonance (MRI) between baseline and after 3 months of TMZ treatment. The secondary outcomes include TMZ serum concentration, rate of cardiac events, NYHA grading, fingertip SpO2, NT-proBNP levels, 6-minute walking test (6MWT), KCCQ-CSS questionnaire score, echocardiography, ECG, routine blood examination, liver and kidney function test, blood pressure and heart rate. DISCUSSION: This trial is designed to explore whether the application of TMZ in adult CCHD patients can improve cardiac function, reduce cardiac events, and improve exercise performance and quality of life. The results will provide targeted drug therapy for CCHD patients with hypoxia and support the application of TMZ in children with CCHD.


Asunto(s)
Enfermedades Cardiovasculares , Cardiopatías Congénitas , Trimetazidina , Adulto , Niño , Humanos , Trimetazidina/uso terapéutico , Calidad de Vida , Hipoxia/etiología , Cardiopatías Congénitas/complicaciones , Cardiopatías Congénitas/tratamiento farmacológico , Enfermedades Cardiovasculares/tratamiento farmacológico , Método Doble Ciego , Vasodilatadores/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
16.
Biol Reprod ; 111(2): 406-413, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38582608

RESUMEN

The aim of this study was to evaluate the role of angiotensin-converting enzyme 1 (ACE1) in H2O2-induced trophoblast cell injury and the potential molecular mechanisms. Oxidative stress was modeled by exposing HTR-8/SVneo cells to 200 µM H2O2. Western blot and real-time quantitative PCR methods were used to detect protein and mRNA expression level of ACE1 in chorionic villus tissue and trophoblast HTR-8/SVneo cell. Inhibition of ACE1 expression was achieved by transfection with small interfering RNA. Then flow cytometry, Cell Counting Kit-8, and Transwell assay was used to assess apoptosis, viability, and migration ability of the cells. Reactive oxygen species (ROS) were detected by fluorescent probes, and malondialdehyde (MDA), superoxide dismutase (SOD), and reduced glutathione (GSH) activities were determined by corresponding detection kits. Angiotensin-converting enzyme 1 expression was upregulated in chorionic villus tissue of patients with missed abortion (MA) compared with individuals with normal early pregnancy abortion. H2O2 induced elevated ACE1 expression in HTR-8/SVneo cells, promoted apoptosis, and inhibited cell viability and migration. Knockdown of ACE1 expression inhibited H2O2-induced effects to enhance cell viability and migration and suppress apoptosis. Additionally, H2O2 stimulation caused increased levels of ROS and MDA and decreased SOD and GSH activity in the cells, whereas knockdown of ACE1 expression led to opposite changes of these oxidative stress indicators. Moreover, knockdown of ACE1 attenuated the inhibitory effect of H2O2 on the Nrf2/HO-1 pathway. Angiotensin-converting enzyme 1 was associated with MA, and it promoted H2O2-induced injury of trophoblast cells through inhibiting the Nrf2 pathway. Therefore, ACE1 may serve as a potential therapeutic target for MA.


Asunto(s)
Aborto Retenido , Peróxido de Hidrógeno , Peptidil-Dipeptidasa A , Trofoblastos , Humanos , Trofoblastos/metabolismo , Trofoblastos/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Peptidil-Dipeptidasa A/genética , Peptidil-Dipeptidasa A/metabolismo , Femenino , Embarazo , Aborto Retenido/genética , Aborto Retenido/metabolismo , Apoptosis/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Línea Celular , Especies Reactivas de Oxígeno/metabolismo , Supervivencia Celular/efectos de los fármacos , Adulto , Movimiento Celular/efectos de los fármacos
17.
J Virol ; 97(3): e0194222, 2023 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-36856422

RESUMEN

African swine fever virus (ASFV) is a large DNA virus that causes African swine fever (ASF), an acute and hemorrhagic disease in pigs with lethality rates of up to 100%. To date, how ASFV efficiently suppress the innate immune response remains enigmatic. In this study, we identified ASFV cysteine protease pS273R as an antagonist of type I interferon (IFN). Overexpression of pS273R inhibited JAK-STAT signaling triggered by type I IFNs. Mechanistically, pS273R interacted with STAT2 and recruited the E3 ubiquitin ligase DCST1, resulting in K48-linked polyubiquitination at K55 of STAT2 and subsequent proteasome-dependent degradation of STAT2. Furthermore, such a function of pS273R in JAK-STAT signaling is not dependent on its protease activity. These findings suggest that ASFV pS273R is important to evade host innate immunity. IMPORTANCE ASF is an acute disease in domestic pigs caused by infection with ASFV. ASF has become a global threat with devastating economic and ecological consequences. To date, there are no commercially available, safe, and efficacious vaccines to prevent ASFV infection. ASFV has evolved a series of strategies to evade host immune responses, facilitating its replication and transmission. Therefore, understanding the immune evasion mechanism of ASFV is helpful for the development of prevention and control measures for ASF. Here, we identified ASFV cysteine protease pS273R as an antagonist of type I IFNs. ASFV pS273R interacted with STAT2 and mediated degradation of STAT2, a transcription factor downstream of type I IFNs that is responsible for induction of various IFN-stimulated genes. pS273R recruited the E3 ubiquitin ligase DCST1 to enhance K48-linked polyubiquitination of STAT2 at K55 in a manner independent of its protease activity. These findings suggest that pS273R is important for ASFV to escape host innate immunity, which sheds new light on the mechanisms of ASFV immune evasion.


Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Proteasas de Cisteína , Interferón Tipo I , Animales , Proteasas de Cisteína/genética , Proteasas de Cisteína/metabolismo , Inmunidad Innata/genética , Interferón Tipo I/metabolismo , Sus scrofa , Porcinos , Ubiquitina-Proteína Ligasas/metabolismo , Factor de Transcripción STAT2/metabolismo , Transducción de Señal
18.
PLoS Pathog ; 18(1): e1010270, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35089988

RESUMEN

ASFV is a large DNA virus that is highly pathogenic in domestic pigs. How this virus is sensed by the innate immune system as well as why it is so virulent remains enigmatic. In this study, we show that the ASFV genome contains AT-rich regions that are recognized by the DNA-directed RNA polymerase III (Pol-III), leading to viral RNA sensor RIG-I-mediated innate immune responses. We further show that ASFV protein I267L inhibits RNA Pol-III-RIG-I-mediated innate antiviral responses. I267L interacts with the E3 ubiquitin ligase Riplet, disrupts Riplet-RIG-I interaction and impairs Riplet-mediated K63-polyubiquitination and activation of RIG-I. I267L-deficient ASFV induces higher levels of interferon-ß, and displays compromised replication both in primary macrophages and pigs compared with wild-type ASFV. Furthermore, I267L-deficiency attenuates the virulence and pathogenesis of ASFV in pigs. These findings suggest that ASFV I267L is an important virulence factor by impairing innate immune responses mediated by the RNA Pol-III-RIG-I axis.


Asunto(s)
Virus de la Fiebre Porcina Africana/patogenicidad , Inmunidad Innata/inmunología , Factores de Virulencia/inmunología , Virulencia/inmunología , Fiebre Porcina Africana/inmunología , Virus de la Fiebre Porcina Africana/inmunología , Animales , ARN Polimerasa III/inmunología , Receptores de Superficie Celular/inmunología , Porcinos
19.
BMC Microbiol ; 24(1): 23, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38229068

RESUMEN

BACKGROUND: Mycoplasma pneumoniae (M. pneumoniae) is an important pathogen of community-acquired pneumonia in children. The factors contributing to the severity of illness caused by M. pneumoniae infection are still under investigation. We aimed to evaluate the sensitivity of common M. pneumoniae detection methods, as well as to analyze the clinical manifestations, genotypes, macrolide resistance, respiratory microenvironment, and their relationship with the severity of illness in children with M. pneumoniae pneumonia in Wuhan. RESULTS: Among 1,259 clinical samples, 461 samples were positive for M. pneumoniae via quantitative polymerase chain reaction (qPCR). Furthermore, we found that while serological testing is not highly sensitive in detecting M. pneumoniae infection, but it may serve as an indicator for predicting severe cases. We successfully identified the adhesin P1 (P1) genotypes of 127 samples based on metagenomic and Sanger sequencing, with P1-type 1 (113/127, 88.98%) being the dominant genotype. No significant difference in pathogenicity was observed among different genotypes. The macrolide resistance rate of M. pneumoniae isolates was 96% (48/50) and all mutations were A2063G in domain V of 23S rRNA gene. There was no significant difference between the upper respiratory microbiome of patients with mild and severe symptoms. CONCLUSIONS: During the period of this study, the main circulating M. pneumoniae was P1-type 1, with a resistance rate of 96%. Key findings include the efficacy of qPCR in detecting M. pneumoniae, the potential of IgM titers exceeding 1:160 as indicators for illness severity, and the lack of a direct correlation between disease severity and genotypic characteristics or respiratory microenvironment. This study is the first to characterize the epidemic and genomic features of M. pneumoniae in Wuhan after the COVID-19 outbreak in 2020, which provides a scientific data basis for monitoring and infection prevention and control of M. pneumoniae in the post-pandemic era.


Asunto(s)
Mycoplasma pneumoniae , Neumonía por Mycoplasma , Niño , Humanos , Mycoplasma pneumoniae/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Epidemiología Molecular , Macrólidos/farmacología , Farmacorresistencia Bacteriana/genética , Neumonía por Mycoplasma/diagnóstico , Neumonía por Mycoplasma/epidemiología , Neumonía por Mycoplasma/tratamiento farmacológico , ARN Ribosómico 23S/genética , Pandemias
20.
Opt Express ; 32(8): 13998-14009, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38859357

RESUMEN

The entanglement properties of quantum synchronization, based on a single-ion phonon laser subjected to an external drive, have been studied. It is found that the maximum value of steady-state entanglement between the ion's internal and external states occurs near the noiseless boundary from synchronization to unsynchronization, accompanied by noticeable oscillatory behaviors during the corresponding time evolution of entanglement. In addition, the later time dynamics of entanglement also indicates the occurrence of frequency entrainment, as evidenced by the strong consistency between the bending of the observed frequency and the emergence of Liouvillian exceptional points (LEPs) in the first two eigenvalues of the Liouvillian eigenspectrum. Moreover, the emergence of LEPs, which is intimately associated with frequency entrainment, should be widely observed in quantum synchronization and can be explored in LEPs-based applications.

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