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1.
Cell ; 181(2): 325-345.e28, 2020 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-32302571

RESUMEN

The mechanisms underlying ribonucleoprotein (RNP) granule assembly, including the basis for establishing and maintaining RNP granules with distinct composition, are unknown. One prominent type of RNP granule is the stress granule (SG), a dynamic and reversible cytoplasmic assembly formed in eukaryotic cells in response to stress. Here, we show that SGs assemble through liquid-liquid phase separation (LLPS) arising from interactions distributed unevenly across a core protein-RNA interaction network. The central node of this network is G3BP1, which functions as a molecular switch that triggers RNA-dependent LLPS in response to a rise in intracellular free RNA concentrations. Moreover, we show that interplay between three distinct intrinsically disordered regions (IDRs) in G3BP1 regulates its intrinsic propensity for LLPS, and this is fine-tuned by phosphorylation within the IDRs. Further regulation of SG assembly arises through positive or negative cooperativity by extrinsic G3BP1-binding factors that strengthen or weaken, respectively, the core SG network.


Asunto(s)
Gránulos Citoplasmáticos/metabolismo , ADN Helicasas/metabolismo , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , ARN Helicasas/metabolismo , Proteínas con Motivos de Reconocimiento de ARN/metabolismo , Ribonucleoproteínas/metabolismo , Línea Celular Tumoral , Citoplasma/metabolismo , Estructuras Citoplasmáticas/metabolismo , Células HEK293 , Humanos , Fosforilación , ARN/metabolismo
2.
Immunity ; 49(5): 899-914.e6, 2018 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-30413360

RESUMEN

Interleukin-2 (IL-2) and downstream transcription factor STAT5 are important for maintaining regulatory T (Treg) cell homeostasis and function. Treg cells can respond to low IL-2 levels, but the mechanisms of STAT5 activation during partial IL-2 deficiency remain uncertain. We identified the serine-threonine kinase Mst1 as a signal-dependent amplifier of IL-2-STAT5 activity in Treg cells. High Mst1 and Mst2 (Mst1-Mst2) activity in Treg cells was crucial to prevent tumor resistance and autoimmunity. Mechanistically, Mst1-Mst2 sensed IL-2 signals to promote the STAT5 activation necessary for Treg cell homeostasis and lineage stability and to maintain the highly suppressive phosphorylated-STAT5+ Treg cell subpopulation. Unbiased quantitative proteomics revealed association of Mst1 with the cytoskeletal DOCK8-LRCHs module. Mst1 deficiency limited Treg cell migration and access to IL-2 and activity of the small GTPase Rac, which mediated downstream STAT5 activation. Collectively, IL-2-STAT5 signaling depends upon Mst1-Mst2 functions to maintain a stable Treg cell pool and immune tolerance.


Asunto(s)
Factor de Crecimiento de Hepatocito/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Receptores de Interleucina-2/metabolismo , Factor de Transcripción STAT5/metabolismo , Transducción de Señal , Linfocitos T Reguladores/metabolismo , Animales , Autoinmunidad/genética , Autoinmunidad/inmunología , Linaje de la Célula/genética , Factor de Crecimiento de Hepatocito/genética , Vía de Señalización Hippo , Interleucina-2/metabolismo , Ratones , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas/genética , Serina-Treonina Quinasa 3 , Linfocitos T Reguladores/inmunología , Proteínas de Unión al GTP rac/metabolismo
3.
Nature ; 600(7888): 308-313, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34795452

RESUMEN

Nutrients are emerging regulators of adaptive immunity1. Selective nutrients interplay with immunological signals to activate mechanistic target of rapamycin complex 1 (mTORC1), a key driver of cell metabolism2-4, but how these environmental signals are integrated for immune regulation remains unclear. Here we use genome-wide CRISPR screening combined with protein-protein interaction networks to identify regulatory modules that mediate immune receptor- and nutrient-dependent signalling to mTORC1 in mouse regulatory T (Treg) cells. SEC31A is identified to promote mTORC1 activation by interacting with the GATOR2 component SEC13 to protect it from SKP1-dependent proteasomal degradation. Accordingly, loss of SEC31A impairs T cell priming and Treg suppressive function in mice. In addition, the SWI/SNF complex restricts expression of the amino acid sensor CASTOR1, thereby enhancing mTORC1 activation. Moreover, we reveal that the CCDC101-associated SAGA complex is a potent inhibitor of mTORC1, which limits the expression of glucose and amino acid transporters and maintains T cell quiescence in vivo. Specific deletion of Ccdc101 in mouse Treg cells results in uncontrolled inflammation but improved antitumour immunity. Collectively, our results establish epigenetic and post-translational mechanisms that underpin how nutrient transporters, sensors and transducers interplay with immune signals for three-tiered regulation of mTORC1 activity and identify their pivotal roles in licensing T cell immunity and immune tolerance.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Nutrientes , Mapas de Interacción de Proteínas , Linfocitos T Reguladores , Animales , Femenino , Masculino , Ratones , Proteínas Portadoras/metabolismo , Sistemas CRISPR-Cas/genética , Factores de Transcripción Forkhead/metabolismo , Genoma/genética , Homeostasis , Tolerancia Inmunológica , Inflamación/patología , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Neoplasias/inmunología , Proteínas Nucleares/metabolismo , Nutrientes/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , Proteínas Quinasas Asociadas a Fase-S/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Transactivadores/metabolismo
4.
Immunity ; 46(3): 488-503, 2017 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-28285833

RESUMEN

The molecular circuits by which antigens activate quiescent T cells remain poorly understood. We combined temporal profiling of the whole proteome and phosphoproteome via multiplexed isobaric labeling proteomics technology, computational pipelines for integrating multi-omics datasets, and functional perturbation to systemically reconstruct regulatory networks underlying T cell activation. T cell receptors activated the T cell proteome and phosphoproteome with discrete kinetics, marked by early dynamics of phosphorylation and delayed ribosome biogenesis and mitochondrial activation. Systems biology analyses identified multiple functional modules, active kinases, transcription factors and connectivity between them, and mitochondrial pathways including mitoribosomes and complex IV. Genetic perturbation revealed physiological roles for mitochondrial enzyme COX10-mediated oxidative phosphorylation in T cell quiescence exit. Our multi-layer proteomics profiling, integrative network analysis, and functional studies define landscapes of the T cell proteome and phosphoproteome and reveal signaling and bioenergetics pathways that mediate lymphocyte exit from quiescence.


Asunto(s)
Activación de Linfocitos/inmunología , Transducción de Señal/inmunología , Linfocitos T/inmunología , Transferasas Alquil y Aril/inmunología , Animales , Metabolismo Energético , Espectrometría de Masas , Proteínas de la Membrana/inmunología , Ratones , Ratones Endogámicos C57BL , Fosforilación , Proteómica , Receptores de Antígenos de Linfocitos T/inmunología
5.
Eur Heart J ; 45(4): 268-283, 2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38036416

RESUMEN

BACKGROUND AND AIMS: Macrophage-derived foam cells play a causal role during the pathogenesis of atherosclerosis. P2Y6 receptor (P2Y6R) highly expressed has been considered as a disease-causing factor in atherogenesis, but the detailed mechanism remains unknown. This study aims to explore P2Y6R in regulation of macrophage foaming, atherogenesis, and its downstream pathways. Furthermore, the present study sought to find a potent P2Y6R antagonist and investigate the feasibility of P2Y6R-targeting therapy for atherosclerosis. METHODS: The P2Y6R expression was examined in human atherosclerotic plaques and mouse artery. Atherosclerosis animal models were established in whole-body P2Y6R or macrophage-specific P2Y6R knockout mice to evaluate the role of P2Y6R. RNA sequencing, DNA pull-down experiments, and proteomic approaches were performed to investigate the downstream mechanisms. High-throughput Glide docking pipeline from repurposing drug library was performed to find potent P2Y6R antagonists. RESULTS: The P2Y6R deficiency alleviated atherogenesis characterized by decreasing plaque formation and lipid deposition of the aorta. Mechanically, deletion of macrophage P2Y6R significantly inhibited uptake of oxidized low-density lipoprotein through decreasing scavenger receptor A expression mediated by phospholipase Cß/store-operated calcium entry pathways. More importantly, P2Y6R deficiency reduced the binding of scavenger receptor A to CALR, accompanied by dissociation of calreticulin and STIM1. Interestingly, thiamine pyrophosphate was found as a potent P2Y6R antagonist with excellent P2Y6R antagonistic activity and binding affinity, of which the pharmacodynamic effect and mechanism on atherosclerosis were verified. CONCLUSIONS: Macrophage P2Y6R regulates phospholipase Cß/store-operated calcium entry/calreticulin signalling pathway to increase scavenger receptor A protein level, thereby improving foam cell formation and atherosclerosis, indicating that the P2Y6R may be a potential therapeutic target for intervention of atherosclerotic diseases using P2Y6R antagonists including thiamine pyrophosphate.


Asunto(s)
Aterosclerosis , Células Espumosas , Receptores Purinérgicos P2 , Humanos , Ratones , Animales , Células Espumosas/metabolismo , Células Espumosas/patología , Calcio/metabolismo , Calreticulina/metabolismo , Calreticulina/farmacología , Proteómica , Tiamina Pirofosfato/metabolismo , Tiamina Pirofosfato/farmacología , Aterosclerosis/genética , Macrófagos/metabolismo , Lipoproteínas LDL/metabolismo , Receptores Depuradores/metabolismo , Ratones Noqueados , Fosfolipasas/metabolismo , Fosfolipasas/farmacología
6.
Nano Lett ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39012768

RESUMEN

Fibers of liquid crystal elastomers (LCEs) as promising artificial muscle show ultralarge and reversible contractile strokes. However, the contractile force is limited by the poor mechanical properties of the LCE fibers. Herein, we report high-strength LCE fibers by introducing a secondary network into the single-network LCE. The double-network LCE (DNLCE) shows considerable improvements in tensile strength (313.9%) and maximum actuation stress (342.8%) compared to pristine LCE. To facilitate the controllability and application, a coiled artificial muscle fiber consisting of DNLCE-coated carbon nanotube (CNT) fiber is prepared. When electrothermally driven, the artificial muscle fiber outputs a high actuation performance and programmable actuation. Furthermore, by knitting the artificial muscle fibers into origami structures, an intelligent gripper and crawling inchworm robot have been demonstrated. These demonstrations provide promising application scenarios for advanced intelligent systems in the future.

7.
Plant J ; 116(5): 1441-1461, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37648415

RESUMEN

Bougainvillea is a typical tropical flower of great ornamental value due to its colorful bracts. The molecular mechanism behind color formation is not well-understood. Therefore, this research conducted metabolome analysis, transcriptome analysis, and multi-flux full-length sequencing in two color bracts of Bougainvillea × buttiana 'Chitra' to investigate the significantly different metabolites (SDMs) and differentially expressed genes (DEGs). Overall, 261 SDMs, including 62 flavonoids and 26 alkaloids, were detected, and flavonols and betalains were significantly differentially accumulated among the two bracts. Furthermore, the complete-length transcriptome of Bougainvillea × buttiana was also developed, which contained 512 493 non-redundant isoforms. Among them, 341 210 (66.58%) displayed multiple annotations in the KOG, GO, NR, KEGG, Pfam, Swissprot, and NT databases. RNA-seq findings revealed that 3610 DEGs were identified between two bracts. Co-expression analysis demonstrated that the DEGs and SDMs involved in flavonol metabolism (such as CHS, CHI, F3H, FLS, CYP75B1, kaempferol, and quercetin) and betacyanin metabolism (DODA, betanidin, and betacyanins) were the main contributors for the canary yellow and red bract formation, respectively. Further investigation revealed that several putative transcription factors (TFs) might interact with the promoters of the genes mentioned above. The expression profiles of the putative TFs displayed that they may positively and negatively regulate the structural genes' expression profiles. The data revealed a potential regulatory network between important genes, putative TFs, and metabolites in the flavonol and betacyanin biosynthesis of Bougainvillea × buttiana 'Chitra' bracts. These findings will serve as a rich genetic resource for future studies that could create new color bracts.


Asunto(s)
Canarios , Nyctaginaceae , Animales , Canarios/genética , Betacianinas , Nyctaginaceae/genética , Perfilación de la Expresión Génica , Transcriptoma/genética , Flavonoles , Metaboloma/genética , Regulación de la Expresión Génica de las Plantas/genética
8.
Hum Genet ; 143(2): 137-149, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38182908

RESUMEN

Several studies have emphasized the role of DNA methylation in vitiligo. However, its profile in human skin of individuals with vitiligo remains unknown. Here, we aimed to study the DNA methylation profile of vitiligo using pairwise comparisons of lesions, peri-lesions, and healthy skin. We investigated DNA methylation levels in six lesional skin, six peri-lesional skin, and eight healthy skin samples using an Illumina 850 K methylation chip. We then integrated DNA methylation data with transcriptome data to identify differentially methylated and expressed genes (DMEGs) and analyzed their functional enrichment. Subsequently, we compared the methylation and transcriptome characteristics of all skin samples, and the related genes were further studied using scRNA-seq data. Finally, validation was performed using an external dataset. We observed more DNA hypomethylated sites in patients with vitiligo. Further integrated analysis identified 264 DMEGs that were mainly functionally enriched in cell division, pigmentation, circadian rhythm, fatty acid metabolism, peroxidase activity, synapse regulation, and extracellular matrix. In addition, in the peri-lesional skin, we found that methylation levels of 102 DMEGs differed prior to changes in their transcription levels and identified 16 key pre-DMEGs (ANLN, CDCA3, CENPA, DEPDC1, ECT2, DEPDC1B, HMMR, KIF18A, KIF18B, TTK, KIF23, DCT, EDNRB, MITF, OCA2, and TYRP1). Single-cell RNA analysis showed that these genes were associated with cycling keratinocytes and melanocytes. Further analysis of cellular communication indicated the involvement of the extracellular matrix. The expression of related genes was verified using an external dataset. To the best of our knowledge, this is the first study to report a comprehensive DNA methylation profile of clinical vitiligo and peri-lesional skin. These findings would contribute to future research on the pathogenesis of vitiligo and potential therapeutic strategies.


Asunto(s)
Vitíligo , Humanos , Vitíligo/genética , Vitíligo/patología , Metilación de ADN , Multiómica , Piel/metabolismo , Piel/patología , ADN , Transcriptoma , China , Proteínas de Ciclo Celular/genética , Cinesinas/genética , Cinesinas/metabolismo , Proteínas de Neoplasias/genética , Proteínas Activadoras de GTPasa/genética
9.
Hum Brain Mapp ; 45(1): e26529, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37991144

RESUMEN

Mild cognitive impairment (MCI) is a critical prodromal stage of Alzheimer's disease (AD), and the mechanism underlying the conversion is not fully explored. Construction and inter-cohort validation of imaging biomarkers for predicting MCI conversion is of great challenge at present, due to lack of longitudinal cohorts and poor reproducibility of various study-specific imaging indices. We proposed a novel framework for inter-cohort MCI conversion prediction, involving comparison of structural, static, and dynamic functional brain features from structural magnetic resonance imaging (sMRI) and resting-state functional MRI (fMRI) between MCI converters (MCI_C) and non-converters (MCI_NC), and support vector machine for construction of prediction models. A total of 218 MCI patients with 3-year follow-up outcome were selected from two independent cohorts: Shanghai Memory Study cohort for internal cross-validation, and Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort for external validation. In comparison with MCI_NC, MCI_C were mainly characterized by atrophy, regional hyperactivity and inter-network hypo-connectivity, and dynamic alterations characterized by regional and connectional instability, involving medial temporal lobe (MTL), posterior parietal cortex (PPC), and occipital cortex. All imaging-based prediction models achieved an area under the curve (AUC) > 0.7 in both cohorts, with the multi-modality MRI models as the best with excellent performances of AUC > 0.85. Notably, the combination of static and dynamic fMRI resulted in overall better performance as relative to static or dynamic fMRI solely, supporting the contribution of dynamic features. This inter-cohort validation study provides a new insight into the mechanisms of MCI conversion involving brain dynamics, and paves a way for clinical use of structural and functional MRI biomarkers in future.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Reproducibilidad de los Resultados , China , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Biomarcadores
10.
Small ; : e2400344, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38497503

RESUMEN

Organic supramolecular photocatalysts have garnered widespread attention due to their adjustable structure and exceptional photocatalytic activity. Herein, a novel bis-dicarboxyphenyl-substituent naphthalenediimide self-assembly supramolecular photocatalyst (SA-NDI-BCOOH) with efficient dual-functional photocatalytic performance is successfully constructed. The large molecular dipole moment and short-range ordered stacking structure of SA-NDI-BCOOH synergistically create a giant internal electric field (IEF), resulting in a remarkable 6.7-fold increase in its charge separation efficiency. Additionally, the tetracarboxylic structure of SA-NDI-BCOOH greatly enhances its hydrophilicity. Thus, SA-NDI-BCOOH demonstrates efficient dual-functional activity for photocatalytic hydrogen and oxygen evolution, with rates of 372.8 and 3.8 µmol h-1 , respectively. Meanwhile, a notable apparent quantum efficiency of 10.86% at 400 nm for hydrogen evolution is achieved, prominently surpassing many reported supramolecular photocatalysts. More importantly, with the help of dual co-catalysts, it exhibits photocatalytic overall water splitting activity with H2 and O2 evolution rates of 3.2 and 1.6 µmol h-1 . Briefly, this work sheds light on enhancing the IEF by controlling the molecular polarity and stacking structure to dramatically improve the photocatalytic performance of supramolecular materials.

11.
Bioinformatics ; 39(4)2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36946294

RESUMEN

MOTIVATION: Reconstructing and analyzing all blood vessels throughout the brain is significant for understanding brain function, revealing the mechanisms of brain disease, and mapping the whole-brain vascular atlas. Vessel segmentation is a fundamental step in reconstruction and analysis. The whole-brain optical microscopic imaging method enables the acquisition of whole-brain vessel images at the capillary resolution. Due to the massive amount of data and the complex vascular features generated by high-resolution whole-brain imaging, achieving rapid and accurate segmentation of whole-brain vasculature becomes a challenge. RESULTS: We introduce HP-VSP, a high-performance vessel segmentation pipeline based on deep learning. The pipeline consists of three processes: data blocking, block prediction, and block fusion. We used parallel computing to parallelize this pipeline to improve the efficiency of whole-brain vessel segmentation. We also designed a lightweight deep neural network based on multi-resolution vessel feature extraction to segment vessels at different scales throughout the brain accurately. We validated our approach on whole-brain vascular data from three transgenic mice collected by HD-fMOST. The results show that our proposed segmentation network achieves the state-of-the-art level under various evaluation metrics. In contrast, the parameters of the network are only 1% of those of similar networks. The established segmentation pipeline could be used on various computing platforms and complete the whole-brain vessel segmentation in 3 h. We also demonstrated that our pipeline could be applied to the vascular analysis. AVAILABILITY AND IMPLEMENTATION: The dataset is available at http://atlas.brainsmatics.org/a/li2301. The source code is freely available at https://github.com/visionlyx/HP-VSP.


Asunto(s)
Aprendizaje Profundo , Ratones , Animales , Encéfalo/diagnóstico por imagen , Imagenología Tridimensional/métodos , Redes Neurales de la Computación , Programas Informáticos , Procesamiento de Imagen Asistido por Computador/métodos
12.
Opt Express ; 32(9): 16140-16155, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38859250

RESUMEN

In this paper, high-order LP modes based Sagnac interference for temperature sensing are proposed and investigated theoretically. Based on the specific high-order LP modes excited through the mode selective couplers (MSCs), we design a stress-induced Panda-type few-mode fiber (FMF) supporting 4 LP modes and construct a Sagnac interferometer to achieve a highly sensitive temperature sensor. The performances of different LP modes (LP01, LP11, LP21, and LP02) are explored under a single Sagnac interferometer and paralleled Sagnac interferometers, respectively. LP21 mode has the highest temperature sensitivity. Compared with fundamental mode (LP01), the temperature sensitivity based on LP21 mode improved by 18.2% at least. In addition, a way to achieve the enhanced optical Vernier effect is proposed. It should be noted that two Sagnac loops are located in two temperature boxes of opposite variation trends, respectively. Both two Sagnac interferometers act as the sensing element, which is different from the traditional optical Vernier effect. The temperature sensitivity of novel enhanced optical Vernier effect is magnified by 8 times, which is larger than 5 times the traditional Vernier effect. The novel approach avoids measurement errors and improves the stability of the sensing system. The focus of this research is on high-order mode interference, which has important guiding significance for the development of highly sensitive Sagnac sensors.

13.
J Magn Reson Imaging ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38970331

RESUMEN

BACKGROUND: Primary central nervous system lymphoma (PCNSL) carries a poor prognosis. Radiomics may hold potential value in prognostic assessment. PURPOSE: To develop and validate an MRI-based radiomics model and combine it with clinical factors to assess progression-free survival (PFS) and overall survival (OS) of patients with PCNSL. STUDY TYPE: Retrospective and prospective. POPULATION: Three hundred seventy-nine patients (179 female, 53 ± 7 years) from 2014 to 2022. FIELD STRENGTH/SEQUENCE: T2/fluid-attenuated inversion recovery, contrast-enhanced T1WI and diffusion-weighted echo-planar imaging sequences on 3.0 T. ASSESSMENT: Radiomics features were extracted from enhanced tumor regions on preoperative multi-sequence MRI. Using a least absolute shrinkage and selection operator (LASSO) Cox regression model to select radiomic signatures in training cohort (N = 169). Cox proportional hazards models were constructed for clinical, radiomics, and combined models, with internal (N = 72) and external (N = 32) cohorts validating model performance. STATISTICAL TESTS: Chi-squared, Mann-Whitney, Kaplan-Meier, log-rank, LASSO, Cox, decision curve analysis, time-dependent Receiver Operating Characteristic, area under the curve (AUC), and likelihood ratio test. P-value <0.05 was considered significant. RESULTS: Follow-up duration was 28.79 ± 22.59 months (median: 25). High-risk patients, determined by the median radiomics score, showed significantly lower survival rates than low-risk patients. Compared with NCCN-IPI, conventional imaging and clinical models, the combined model achieved the highest C-index for both PFS (0.660 internal, 0.802 external) and OS (0.733 internal, 0.781 external) in validation. Net benefit was greater with radiomics than with clinical alone. The combined model exhibited performance with AUCs of 0.680, 0.752, and 0.830 for predicting 1-year, 3-year, and 5-year PFS, and 0.770, 0.789, and 0.863 for OS in internal validation, with PFS AUCs of 0.860 and 0.826 and OS AUCs of 0.859 and 0.748 for 1-year and 3-year survival in external validation. DATA CONCLUSION: Incorporating a multi-sequence MR-based radiomics model into clinical models enhances the assess accuracy for the prognosis of PCNSL. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 2.

14.
Eur Radiol ; 34(7): 4364-4375, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38127076

RESUMEN

OBJECTIVE: To develop a discrimination pipeline concerning both radiomics and spatial distribution features of brain lesions for discrimination of multiple sclerosis (MS), aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorder (NMOSD), and myelin-oligodendrocyte-glycoprotein-IgG-associated disorder (MOGAD). METHODS: Hyperintensity T2 lesions were delineated in 212 brain MRI scans of MS (n = 63), NMOSD (n = 87), and MOGAD (n = 45) patients. To avoid the effect of fixed training/test dataset sampling when developing machine learning models, patients were allocated into 4 sub-groups for cross-validation. For each scan, 351 radiomics and 27 spatial distribution features were extracted. Three models, i.e., multi-lesion radiomics, spatial distribution, and joint models, were constructed using random forest and logistic regression algorithms for differentiating: MS from the others (MS models) and MOGAD from NMOSD (MOG-NMO models), respectively. Then, the joint models were combined with demographic characteristics (i.e., age and sex) to create MS and MOG-NMO discriminators, respectively, based on which a three-disease discrimination pipeline was generated and compared with radiologists. RESULTS: For classification of both MS-others and MOG-NMO, the joint models performed better than radiomics or spatial distribution model solely. The MS discriminator achieved AUC = 0.909 ± 0.027 and bias-corrected C-index = 0.909 ± 0.027, and the MOG-NMO discriminator achieved AUC = 0.880 ± 0.064 and bias-corrected C-index = 0.883 ± 0.068. The three-disease discrimination pipeline differentiated MS, NMOSD, and MOGAD patients with 75.0% accuracy, prominently outperforming the three radiologists (47.6%, 56.6%, and 66.0%). CONCLUSIONS: The proposed pipeline integrating multi-lesion radiomics and spatial distribution features could effectively differentiate MS, NMOSD, and MOGAD. CLINICAL RELEVANCE STATEMENT: The discrimination pipeline merging both radiomics and spatial distribution features of brain lesions may facilitate the differential diagnoses of multiple sclerosis, neuromyelitis optica spectrum disorder, and myelin-oligodendrocyte-glycoprotein-IgG-associated disorder. KEY POINTS: • Our study introduces an approach by combining radiomics and spatial distribution models. • The joint model exhibited superior performance in distinguishing multiple sclerosis from aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorder and myelin-oligodendrocyte-glycoprotein-IgG-associated disorder as well as discriminating the latter two diseases. • The three-disease discrimination pipeline showcased remarkable accuracy, surpassing the performance of experienced radiologists, highlighting its potential as a valuable diagnostic tool.


Asunto(s)
Inmunoglobulina G , Imagen por Resonancia Magnética , Esclerosis Múltiple , Glicoproteína Mielina-Oligodendrócito , Neuromielitis Óptica , Humanos , Neuromielitis Óptica/diagnóstico por imagen , Neuromielitis Óptica/inmunología , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/inmunología , Imagen por Resonancia Magnética/métodos , Femenino , Masculino , Adulto , Glicoproteína Mielina-Oligodendrócito/inmunología , Persona de Mediana Edad , Diagnóstico Diferencial , Encéfalo/diagnóstico por imagen , Acuaporina 4/inmunología , Radiómica
15.
J Nat Prod ; 87(4): 893-905, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38417166

RESUMEN

The bridged polycyclic sesquiterpenoids derived from sativene, isosativene, and longifolene have unique structures, and many chemical synthesis approaches with at least 10 steps have been reported. However, their biosynthetic pathway remains undescribed. A minimal biosynthetic gene cluster (BGC), named bip, encoding a sesquiterpene cyclase (BipA) and a cytochrome P450 (BipB) is characterized to produce such complex sesquiterpenoids with multiple carbon skeletons based on enzymatic assays, heterologous expression, and precursor experiments. BipA is demonstrated as a versatile cyclase with (-)-sativene as the dominant product and (-)-isosativene and (-)-longifolene as minor ones. BipB is capable of hydroxylating different enantiomeric sesquiterpenes, such as (-)-longifolene and (+)-longifolene, at C-15 and C-14 in turn. The C-15- or both C-15- and C-14-hydroxylated products are then further oxidized by unclustered oxidases, resulting in a structurally diverse array of sesquiterpenoids. Bioinformatic analysis reveals the BipB homologues as a discrete clade of fungal sesquiterpene P450s. These findings elucidate the concise and divergent biosynthesis of such intricate bridged polycyclic sesquiterpenoids, offer valuable biocatalysts for biotransformation, and highlight the distinct biosynthetic strategy employed by nature compared to chemical synthesis.


Asunto(s)
Sistema Enzimático del Citocromo P-450 , Familia de Multigenes , Estructura Molecular , Sistema Enzimático del Citocromo P-450/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Sesquiterpenos/metabolismo , Sesquiterpenos/química , Vías Biosintéticas/genética , Sesquiterpenos Policíclicos/química , Sesquiterpenos Policíclicos/metabolismo , Estereoisomerismo
16.
Nature ; 558(7708): 141-145, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29849151

RESUMEN

Dendritic cells orchestrate the crosstalk between innate and adaptive immunity. CD8α+ dendritic cells present antigens to CD8+ T cells and elicit cytotoxic T cell responses to viruses, bacteria and tumours 1 . Although lineage-specific transcriptional regulators of CD8α+ dendritic cell development have been identified 2 , the molecular pathways that selectively orchestrate CD8α+ dendritic cell function remain elusive. Moreover, metabolic reprogramming is important for dendritic cell development and activation3,4, but metabolic dependence and regulation of dendritic cell subsets are largely uncharacterized. Here we use a data-driven systems biology algorithm (NetBID) to identify a role of the Hippo pathway kinases Mst1 and Mst2 (Mst1/2) in selectively programming CD8α+ dendritic cell function and metabolism. Our NetBID analysis reveals a marked enrichment of the activities of Hippo pathway kinases in CD8α+ dendritic cells relative to CD8α- dendritic cells. Dendritic cell-specific deletion of Mst1/2-but not Lats1 and Lats2 (Lats1/2) or Yap and Taz (Yap/Taz), which mediate canonical Hippo signalling-disrupts homeostasis and function of CD8+ T cells and anti-tumour immunity. Mst1/2-deficient CD8α+ dendritic cells are impaired in presentation of extracellular proteins and cognate peptides to prime CD8+ T cells, while CD8α- dendritic cells that lack Mst1/2 have largely normal function. Mechanistically, compared to CD8α- dendritic cells, CD8α+ dendritic cells exhibit much stronger oxidative metabolism and critically depend on Mst1/2 signalling to maintain bioenergetic activities and mitochondrial dynamics for their functional capacities. Further, selective expression of IL-12 by CD8α+ dendritic cells depends on Mst1/2 and the crosstalk with non-canonical NF-κB signalling. Our findings identify Mst1/2 as selective drivers of CD8α+ dendritic cell function by integrating metabolic activity and cytokine signalling, and highlight that the interplay between immune signalling and metabolic reprogramming underlies the unique functions of dendritic cell subsets.


Asunto(s)
Antígenos CD8/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Algoritmos , Animales , Antígenos CD8/inmunología , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Reactividad Cruzada/inmunología , Células Dendríticas/citología , Vía de Señalización Hippo , Homeostasis , Interleucina-12/inmunología , Interleucina-12/metabolismo , Ratones , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Proteínas Serina-Treonina Quinasas/deficiencia , Proteínas Serina-Treonina Quinasas/genética , Serina-Treonina Quinasa 3 , Proteínas Supresoras de Tumor
17.
Nature ; 558(7710): 435-439, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29899451

RESUMEN

Sleep and wake have global effects on brain physiology, from molecular changes1-4 and neuronal activities to synaptic plasticity3-7. Sleep-wake homeostasis is maintained by the generation of a sleep need that accumulates during waking and dissipates during sleep8-11. Here we investigate the molecular basis of sleep need using quantitative phosphoproteomic analysis of the sleep-deprived and Sleepy mouse models of increased sleep need. Sleep deprivation induces cumulative phosphorylation of the brain proteome, which dissipates during sleep. Sleepy mice, owing to a gain-of-function mutation in the Sik3 gene 12 , have a constitutively high sleep need despite increased sleep amount. The brain proteome of these mice exhibits hyperphosphorylation, similar to that seen in the brain of sleep-deprived mice. Comparison of the two models identifies 80 mostly synaptic sleep-need-index phosphoproteins (SNIPPs), in which phosphorylation states closely parallel changes of sleep need. SLEEPY, the mutant SIK3 protein, preferentially associates with and phosphorylates SNIPPs. Inhibition of SIK3 activity reduces phosphorylation of SNIPPs and slow wave activity during non-rapid-eye-movement sleep, the best known measurable index of sleep need, in both Sleepy mice and sleep-deprived wild-type mice. Our results suggest that phosphorylation of SNIPPs accumulates and dissipates in relation to sleep need, and therefore SNIPP phosphorylation is a molecular signature of sleep need. Whereas waking encodes memories by potentiating synapses, sleep consolidates memories and restores synaptic homeostasis by globally downscaling excitatory synapses4-6. Thus, the phosphorylation-dephosphorylation cycle of SNIPPs may represent a major regulatory mechanism that underlies both synaptic homeostasis and sleep-wake homeostasis.


Asunto(s)
Encéfalo/metabolismo , Homeostasis , Fosfoproteínas/análisis , Fosfoproteínas/metabolismo , Proteoma/análisis , Proteómica , Sueño/fisiología , Animales , Encéfalo/fisiología , Mutación con Ganancia de Función , Masculino , Consolidación de la Memoria/fisiología , Ratones , Ratones Endogámicos C57BL , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteoma/metabolismo , Privación de Sueño/metabolismo , Privación de Sueño/fisiopatología , Sinapsis/fisiología , Vigilia/fisiología
18.
Retina ; 44(7): 1209-1216, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38359396

RESUMEN

PURPOSE: To explore the clinical value of ß-D-glucan (BDG) testing and metagenomic next-generation sequencing (mNGS) for detecting the pathogens of fungal endophthalmitis (FE). METHODS: This study included 32 cases (32 eyes) with FE and 20 cases (20 eyes) with intraocular inflammation caused by other etiologies. All patients underwent extraction of aqueous humor or vitreous fluid samples for BDG testing and mNGS. The diagnostic performance and total clinical concordance rate of BDG testing and mNGS for FE were evaluated and calculated based on the results of the clinical diagnosis. RESULTS: Among the clinically diagnosed FE, the positivity rates of BDG testing and mNGS (90.63%) were both significantly higher ( P < 0.001) than that of microbial cultures (53.13%). There was 100% consistency in pathogen identification using mNGS and culture identification for culture-positive cases. The area under the curve was 0.927 for BDG testing and 0.853 for mNGS. When the two tests were combined, sensitivity (93.75%), specificity (100.00%), and total clinical concordance rate (96.15%) were all improved, compared with the single tests. CONCLUSION: The positive rates of BDG test and mNGS were markedly higher than those of cultures in FE identification. The combination of these two tests showed improved performance when compared with individual tests.


Asunto(s)
Humor Acuoso , Endoftalmitis , Infecciones Fúngicas del Ojo , Secuenciación de Nucleótidos de Alto Rendimiento , Metagenómica , Cuerpo Vítreo , beta-Glucanos , Humanos , Infecciones Fúngicas del Ojo/diagnóstico , Infecciones Fúngicas del Ojo/microbiología , Endoftalmitis/diagnóstico , Endoftalmitis/microbiología , Masculino , Persona de Mediana Edad , Femenino , Humor Acuoso/microbiología , beta-Glucanos/análisis , Cuerpo Vítreo/microbiología , Anciano , Metagenómica/métodos , Adulto , Estudios Retrospectivos , Hongos/aislamiento & purificación , Hongos/genética , ADN de Hongos/análisis , Proteoglicanos , Anciano de 80 o más Años
19.
Curr Microbiol ; 81(8): 252, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953991

RESUMEN

Spiroplasma, belonging to the class Mollicutes, is a small, helical, motile bacterium lacking a cell wall. Its host range includes insects, plants, and aquatic crustaceans. Recently, a few human cases of Spiroplasma infection have been reported. The diseases caused by Spiroplasma have brought about serious economic losses and hindered the healthy development of agriculture. The pathogenesis of Spiroplasma involves the ability to adhere, such as through the terminal structure of Spiroplasma, colonization, and invasive enzymes. However, the exact pathogenic mechanism of Spiroplasma remains a mystery. Therefore, we systematically summarize all the information about Spiroplasma in this review article. This provides a reference for future studies on virulence factors and treatment strategies of Spiroplasma.


Asunto(s)
Spiroplasma , Factores de Virulencia , Spiroplasma/genética , Animales , Humanos , Factores de Virulencia/genética , Virulencia , Infecciones por Bacterias Gramnegativas/microbiología , Plantas/microbiología
20.
Ecotoxicol Environ Saf ; 272: 116089, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38354436

RESUMEN

Exposure to cadmium (Cd), a toxic heavy metal classified as an environmental endocrine disruptor, can exert significant toxicity in both animals and humans. However, the potential effects of Cd exposure on socioemotional behaviors are still poorly understood, as are the underlying mechanisms. In the present study, employing a series of behavioral tests as well as 16 S rRNA sequencing analysis, we investigated the long-term effects of Cd exposure on socioemotional behaviors and their associated mechanisms in mice based on the brain-gut interaction theory. The results showed that postweaning exposure to Cd reduced the ability to resist depression, decreased social interaction, subtly altered sexual preference, and changed the composition of the gut microbiota in male mice during adolescence. These findings provided direct evidence for the deleterious effects of exposure to Cd in the postweaning period on socioemotional behaviors later in adolescence, and suggested that these effects of Cd exposure may be linked to changes in the gut microbiota.


Asunto(s)
Cadmio , Microbioma Gastrointestinal , Humanos , Masculino , Animales , Ratones , Adolescente , Cadmio/toxicidad
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