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1.
Cell ; 181(6): 1423-1433.e11, 2020 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-32416069

RESUMEN

Many COVID-19 patients infected by SARS-CoV-2 virus develop pneumonia (called novel coronavirus pneumonia, NCP) and rapidly progress to respiratory failure. However, rapid diagnosis and identification of high-risk patients for early intervention are challenging. Using a large computed tomography (CT) database from 3,777 patients, we developed an AI system that can diagnose NCP and differentiate it from other common pneumonia and normal controls. The AI system can assist radiologists and physicians in performing a quick diagnosis especially when the health system is overloaded. Significantly, our AI system identified important clinical markers that correlated with the NCP lesion properties. Together with the clinical data, our AI system was able to provide accurate clinical prognosis that can aid clinicians to consider appropriate early clinical management and allocate resources appropriately. We have made this AI system available globally to assist the clinicians to combat COVID-19.


Asunto(s)
Inteligencia Artificial , Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Tomografía Computarizada por Rayos X , COVID-19 , China , Estudios de Cohortes , Infecciones por Coronavirus/patología , Infecciones por Coronavirus/terapia , Conjuntos de Datos como Asunto , Humanos , Pulmón/patología , Modelos Biológicos , Pandemias , Proyectos Piloto , Neumonía Viral/patología , Neumonía Viral/terapia , Pronóstico , Radiólogos , Insuficiencia Respiratoria/diagnóstico
2.
Mol Cell ; 83(7): 1043-1060.e10, 2023 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-36854302

RESUMEN

Repair of DNA double-strand breaks (DSBs) elicits three-dimensional (3D) chromatin topological changes. A recent finding reveals that 53BP1 assembles into a 3D chromatin topology pattern around DSBs. How this formation of a higher-order structure is configured and regulated remains enigmatic. Here, we report that SLFN5 is a critical factor for 53BP1 topological arrangement at DSBs. Using super-resolution imaging, we find that SLFN5 binds to 53BP1 chromatin domains to assemble a higher-order microdomain architecture by driving damaged chromatin dynamics at both DSBs and deprotected telomeres. Mechanistically, we propose that 53BP1 topology is shaped by two processes: (1) chromatin mobility driven by the SLFN5-LINC-microtubule axis and (2) the assembly of 53BP1 oligomers mediated by SLFN5. In mammals, SLFN5 deficiency disrupts the DSB repair topology and impairs non-homologous end joining, telomere fusions, class switch recombination, and sensitivity to poly (ADP-ribose) polymerase inhibitor. We establish a molecular mechanism that shapes higher-order chromatin topologies to safeguard genomic stability.


Asunto(s)
Cromatina , Reparación del ADN , Animales , Cromatina/genética , Roturas del ADN de Doble Cadena , Reparación del ADN por Unión de Extremidades , Mamíferos/metabolismo , Proteínas de Unión a Telómeros/genética , Proteína 1 de Unión al Supresor Tumoral P53/genética , Proteína 1 de Unión al Supresor Tumoral P53/metabolismo , Proteínas de Ciclo Celular/metabolismo
4.
Mol Cell ; 79(5): 824-835.e5, 2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32649882

RESUMEN

DNA-protein crosslinks (DPCs) are highly toxic DNA lesions that threaten genomic integrity. Recent findings highlight that SPRTN, a specialized DNA-dependent metalloprotease, is a central player in proteolytic cleavage of DPCs. Previous studies suggest that SPRTN deubiquitination is important for its chromatin association and activation. However, the regulation and consequences of SPRTN deubiquitination remain unclear. Here we report that, in response to DPC induction, the deubiquitinase VCPIP1/VCIP135 is phosphorylated and activated by ATM/ATR. VCPIP1, in turn, deubiquitinates SPRTN and promotes its chromatin relocalization. Deubiquitination of SPRTN is required for its subsequent acetylation, which promotes SPRTN relocation to the site of chromatin damage. Furthermore, Vcpip1 knockout mice are prone to genomic instability and premature aging. We propose a model where two sequential post-translational modifications (PTMs) regulate SPRTN chromatin accessibility to repair DPCs and maintain genomic stability and a healthy lifespan.


Asunto(s)
Envejecimiento/genética , Reparación del ADN , Proteínas de Unión al ADN/metabolismo , Acetilación , Envejecimiento/metabolismo , Animales , Línea Celular , Daño del ADN , Proteínas de Unión al ADN/genética , Enzimas Desubicuitinizantes/metabolismo , Endopeptidasas/metabolismo , Femenino , Inestabilidad Genómica , Células HEK293 , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Fosforilación , Dominios Proteicos , Procesamiento Proteico-Postraduccional , Ubiquitinación
5.
Proc Natl Acad Sci U S A ; 121(37): e2316256121, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39226366

RESUMEN

Trajectory inference methods are essential for analyzing the developmental paths of cells in single-cell sequencing datasets. It provides insights into cellular differentiation, transitions, and lineage hierarchies, helping unravel the dynamic processes underlying development and disease progression. However, many existing tools lack a coherent statistical model and reliable uncertainty quantification, limiting their utility and robustness. In this paper, we introduce VITAE (Variational Inference for Trajectory by AutoEncoder), a statistical approach that integrates a latent hierarchical mixture model with variational autoencoders to infer trajectories. The statistical hierarchical model enhances the interpretability of our framework, while the posterior approximations generated by our variational autoencoder ensure computational efficiency and provide uncertainty quantification of cell projections along trajectories. Specifically, VITAE enables simultaneous trajectory inference and data integration, improving the accuracy of learning a joint trajectory structure in the presence of biological and technical heterogeneity across datasets. We show that VITAE outperforms other state-of-the-art trajectory inference methods on both real and synthetic data under various trajectory topologies. Furthermore, we apply VITAE to jointly analyze three distinct single-cell RNA sequencing datasets of the mouse neocortex, unveiling comprehensive developmental lineages of projection neurons. VITAE effectively reduces batch effects within and across datasets and uncovers finer structures that might be overlooked in individual datasets. Additionally, we showcase VITAE's efficacy in integrative analyses of multiomic datasets with continuous cell population structures.


Asunto(s)
Aprendizaje Profundo , Genómica , Análisis de la Célula Individual , Análisis de la Célula Individual/métodos , Animales , Ratones , Genómica/métodos , Análisis de Secuencia de ARN/métodos , Humanos
6.
N Engl J Med ; 389(20): 1851-1861, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37870969

RESUMEN

BACKGROUND: Selpercatinib, a highly selective, potent RET inhibitor, has shown efficacy in advanced RET-mutant medullary thyroid cancer in a phase 1-2 trial, but its efficacy as compared with approved multikinase inhibitors is unclear. METHODS: We conducted a phase 3, randomized trial comparing selpercatinib as first-line therapy with the physician's choice of cabozantinib or vandetanib (control group). Eligible patients had progressive disease documented within 14 months before enrollment. The primary end point in the protocol-specified interim efficacy analysis was progression-free survival, assessed by blinded independent central review. Crossover to selpercatinib was permitted among patients in the control group after disease progression. Treatment failure-free survival, assessed by blinded independent central review, was a secondary, alpha-controlled end point that was to be tested only if progression-free survival was significant. Among the other secondary end points were overall response and safety. RESULTS: A total of 291 patients underwent randomization. At a median follow-up of 12 months, median progression-free survival as assessed by blinded independent central review was not reached in the selpercatinib group and was 16.8 months (95% confidence interval [CI], 12.2 to 25.1) in the control group (hazard ratio for disease progression or death, 0.28; 95% CI, 0.16 to 0.48; P<0.001). Progression-free survival at 12 months was 86.8% (95% CI, 79.8 to 91.6) in the selpercatinib group and 65.7% (95% CI, 51.9 to 76.4) in the control group. Median treatment failure-free survival as assessed by blinded independent central review was not reached in the selpercatinib group and was 13.9 months in the control group (hazard ratio for disease progression, discontinuation due to treatment-related adverse events, or death, 0.25; 95% CI, 0.15 to 0.42; P<0.001). Treatment failure-free survival at 12 months was 86.2% (95% CI, 79.1 to 91.0) in the selpercatinib group and 62.1% (95% CI, 48.9 to 72.8) in the control group. The overall response was 69.4% (95% CI, 62.4 to 75.8) in the selpercatinib group and 38.8% (95% CI, 29.1 to 49.2) in the control group. Adverse events led to a dose reduction in 38.9% of the patients in the selpercatinib group, as compared with 77.3% in the control group, and to treatment discontinuation in 4.7% and 26.8%, respectively. CONCLUSIONS: Selpercatinib treatment resulted in superior progression-free survival and treatment failure-free survival as compared with cabozantinib or vandetanib in patients with RET-mutant medullary thyroid cancer. (Funded by Loxo Oncology, a subsidiary of Eli Lilly; LIBRETTO-531 ClinicalTrials.gov number, NCT04211337.).


Asunto(s)
Antineoplásicos , Piridinas , Neoplasias de la Tiroides , Humanos , Progresión de la Enfermedad , Piperidinas/efectos adversos , Piperidinas/uso terapéutico , Proteínas Proto-Oncogénicas c-ret/genética , Piridinas/efectos adversos , Piridinas/uso terapéutico , Quinazolinas/efectos adversos , Quinazolinas/uso terapéutico , Neoplasias de la Tiroides/tratamiento farmacológico , Neoplasias de la Tiroides/genética , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico
7.
PLoS Pathog ; 20(4): e1012141, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38626263

RESUMEN

Kaposi's sarcoma-associated herpesvirus (KSHV) is a double-stranded DNA virus etiologically associated with multiple malignancies. Both latency and sporadic lytic reactivation contribute to KSHV-associated malignancies, however, the specific roles of many KSHV lytic gene products in KSHV replication remain elusive. In this study, we report that ablation of ORF55, a late gene encoding a tegument protein, does not impact KSHV lytic reactivation but significantly reduces the production of progeny virions. We found that cysteine 10 and 11 (C10 and C11) of pORF55 are palmitoylated, and the palmytoilation is essential for its Golgi localization and secondary envelope formation. Palmitoylation-defective pORF55 mutants are unstable and undergo proteasomal degradation. Notably, introduction of a putative Golgi localization sequence to these palmitoylation-defective pORF55 mutants restores Golgi localization and fully reinstates KSHV progeny virion production. Together, our study provides new insight into the critical role of pORF55 palmitoylation in KSHV progeny virion production and offers potential therapeutic targets for the treatment of related malignancies.


Asunto(s)
Aparato de Golgi , Herpesvirus Humano 8 , Lipoilación , Proteínas Virales , Virión , Replicación Viral , Herpesvirus Humano 8/fisiología , Herpesvirus Humano 8/metabolismo , Aparato de Golgi/metabolismo , Aparato de Golgi/virología , Humanos , Virión/metabolismo , Proteínas Virales/metabolismo , Proteínas Virales/genética , Replicación Viral/fisiología , Células HEK293
8.
PLoS Pathog ; 20(1): e1011943, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38215174

RESUMEN

Deubiquitinases (DUBs) remove ubiquitin from substrates and play crucial roles in diverse biological processes. However, our understanding of deubiquitination in viral replication remains limited. Employing an oncogenic human herpesvirus Kaposi's sarcoma-associated herpesvirus (KSHV) to probe the role of protein deubiquitination, we found that Ovarian tumor family deubiquitinase 4 (OTUD4) promotes KSHV reactivation. OTUD4 interacts with the replication and transcription activator (K-RTA), a key transcription factor that controls KSHV reactivation, and enhances K-RTA stability by promoting its deubiquitination. Notably, the DUB activity of OTUD4 is not required for K-RTA stabilization; instead, OTUD4 functions as an adaptor protein to recruit another DUB, USP7, to deubiquitinate K-RTA and facilitate KSHV lytic reactivation. Our study has revealed a novel mechanism whereby KSHV hijacks OTUD4-USP7 deubiquitinases to promote lytic reactivation, which could be potentially harnessed for the development of new antiviral therapies.


Asunto(s)
Herpesvirus Humano 8 , Proteínas Inmediatas-Precoces , Sarcoma de Kaposi , Humanos , Proteínas Inmediatas-Precoces/metabolismo , Peptidasa Específica de Ubiquitina 7/genética , Peptidasa Específica de Ubiquitina 7/metabolismo , Transactivadores/genética , Herpesvirus Humano 8/genética , Replicación Viral , Regulación Viral de la Expresión Génica , Activación Viral , Proteasas Ubiquitina-Específicas/metabolismo
9.
J Immunol ; 212(1): 130-142, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37975680

RESUMEN

Pigs are the most suitable model to study various therapeutic strategies and drugs for human beings, although knowledge about cell type-specific transcriptomes and heterogeneity is poorly available. Through single-cell RNA sequencing and flow cytometry analysis of the types in the jejunum of pigs, we found that innate lymphoid cells (ILCs) existed in the lamina propria lymphocytes (LPLs) of the jejunum. Then, through flow sorting of live/dead-lineage (Lin)-CD45+ cells and single-cell RNA sequencing, we found that ILCs in the porcine jejunum were mainly ILC3s, with a small number of NK cells, ILC1s, and ILC2s. ILCs coexpressed IL-7Rα, ID2, and other genes and differentially expressed RORC, GATA3, and other genes but did not express the CD3 gene. ILC3s can be divided into four subgroups, and genes such as CXCL8, CXCL2, IL-22, IL-17, and NCR2 are differentially expressed. To further detect and identify ILC3s, we verified the classification of ILCs in the porcine jejunum subgroup and the expression of related hallmark genes at the protein level by flow cytometry. For systematically characterizing ILCs in the porcine intestines, we combined our pig ILC dataset with publicly available human and mice ILC data and identified that the human and pig ILCs shared more common features than did those mouse ILCs in gene signatures and cell states. Our results showed in detail for the first time (to our knowledge) the gene expression of porcine jejunal ILCs, the subtype classification of ILCs, and the markers of various ILCs, which provide a basis for an in-depth exploration of porcine intestinal mucosal immunity.


Asunto(s)
Inmunidad Innata , Linfocitos , Humanos , Animales , Ratones , Porcinos , Yeyuno , Células Asesinas Naturales , Membrana Mucosa
10.
J Virol ; 98(8): e0103924, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39012142

RESUMEN

In maintaining organismal homeostasis, gut immunity plays a crucial role. The coordination between the microbiota and the immune system through bidirectional interactions regulates the impact of microorganisms on the host. Our research focused on understanding the relationships between substantial changes in jejunal intestinal flora and metabolites and intestinal immunity during porcine epidemic diarrhea virus (PEDV) infection in piglets. We discovered that Lactobacillus rhamnosus GG (LGG) could effectively prevent PEDV infection in piglets. Further investigation revealed that LGG metabolites interact with type 3 innate lymphoid cells (ILC3s) in the jejunum of piglets through the aryl hydrocarbon receptor (AhR). This interaction promotes the activation of ILC3s and the production of interleukin-22 (IL-22). Subsequently, IL-22 facilitates the proliferation of IPEC-J2 cells and activates the STAT3 signaling pathway, thereby preventing PEDV infection. Moreover, the AhR receptor influences various cell types within organoids, including intestinal stem cells (ISCs), Paneth cells, and enterocytes, to promote their growth and development, suggesting that AhR has a broad impact on intestinal health. In conclusion, our study demonstrated the ability of LGG to modulate intestinal immunity and effectively prevent PEDV infection in piglets. These findings highlight the potential application of LGG as a preventive measure against viral infections in livestock.IMPORTANCEWe observed high expression of the AhR receptor on pig and human ILC3s, although its expression was negligible in mouse ILC3s. ILC3s are closely related to the gut microbiota, particularly the secretion of IL-22 stimulated by microbial signals, which plays a crucial regulatory role in intestinal immunity. In our study, we found that metabolites produced by beneficial gut bacteria interact with ILC3s through AhR, thereby maintaining intestinal immune homeostasis in pigs. Moreover, LGG feeding can enhance the activation of ILC3s and promote IL-22 secretion in the intestines of piglets, ultimately preventing PEDV infection.


Asunto(s)
Infecciones por Coronavirus , Inmunidad Innata , Interleucina-22 , Interleucinas , Linfocitos , Virus de la Diarrea Epidémica Porcina , Receptores de Hidrocarburo de Aril , Animales , Receptores de Hidrocarburo de Aril/metabolismo , Porcinos , Interleucinas/metabolismo , Virus de la Diarrea Epidémica Porcina/inmunología , Linfocitos/inmunología , Linfocitos/metabolismo , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/veterinaria , Infecciones por Coronavirus/virología , Infecciones por Coronavirus/metabolismo , Microbioma Gastrointestinal/inmunología , Enfermedades de los Porcinos/inmunología , Enfermedades de los Porcinos/virología , Enfermedades de los Porcinos/prevención & control , Enfermedades de los Porcinos/microbiología , Yeyuno/inmunología , Yeyuno/metabolismo , Transducción de Señal , Ligandos , Intestinos/inmunología , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo
11.
Hepatology ; 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39250438

RESUMEN

BACKGROUND AIMS: Partial hepatectomy (PHx)-induced liver regeneration causes the increase in relative blood flow rate within the liver, which dilates hepatic sinusoids and applies mechanical stretch on liver sinusoidal endothelial cells (LSECs). Heparin-binding EGF-like growth factor (HB-EGF) is a crucial growth factor during liver regeneration. We aimed to investigate whether this sinusoidal dilation-induced stretch promotes HB-EGF secretion in LSECs and what the related molecular mechanism is. APPROACH RESULTS: In vivo PHx, ex vivo liver perfusion and in vitro LSEC mechanical stretch were applied to detect HB-EGF expression in LSECs and hepatocyte proliferation. Knockdown or inhibition of mechanosensitive proteins were used to unravel the molecular mechanism in response to stretch. This stretch triggers amplitude- and duration-dependent HB-EGF up-regulation in LSECs, which is mediated by Yes-associated protein (YAP) nuclear translocation and binding to TEAD. This YAP translocation is achieved in two ways: On one hand, F-actin polymerization-mediated expansion of nuclear pores promotes YAP entry into nucleus passively. On the other hand, F-actin polymerization up-regulates the expression of BAG family molecular chaperone regulator 3 (BAG-3), which binds with YAP to enter nucleus cooperatively. In this process, ß1-integrin serves as a target mechanosensory in stretch-induced signaling pathways. This HB-EGF secretion-promoted liver regeneration after 2/3 PHx is attenuated in endothelial cell-specific Yap1-deficient mice. CONCLUSIONS: Our findings indicate that mechanical stretch-induced HB-EGF up-regulation in LSECs via YAP translocation can promote the hepatocyte proliferation during liver regeneration through a mechanocrine manner, which deepens the understanding of the mechanical-biological coupling in liver regeneration.

12.
Plant Physiol ; 194(3): 1674-1691, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-37831423

RESUMEN

Lineage-specific terpenoids have arisen throughout the evolution of land plants and are believed to play a role in interactions between plants and the environment. Species-specific gene clusters in plants have provided insight on the evolution of secondary metabolism. Lauraceae is an ecologically important plant family whose members are also of considerable economic value given their monoterpene contents. However, the gene cluster responsible for the biosynthesis of monoterpenes remains yet to be elucidated. Here, a Lauraceae-specific citral biosynthetic gene cluster (CGC) was identified and investigated using a multifaceted approach that combined phylogenetic, collinearity, and biochemical analyses. The CGC comprises MYB44 as a regulator and 2 alcohol dehydrogenases (ADHs) as modifying enzymes, which derived from species-specific tandem and proximal duplication events. Activity and substrate divergence of the ADHs has resulted in the fruit of mountain pepper (Litsea cubeba), a core Lauraceae species, consisting of more than 80% citral. In addition, MYB44 negatively regulates citral biosynthesis by directly binding to the promoters of the ADH-encoding genes. The aggregation of citral biosynthetic pathways suggests that they may form the basis of important characteristics that enhance adaptability. The findings of this study provide insights into the evolution of and the regulatory mechanisms involved in plant terpene biosynthesis.


Asunto(s)
Monoterpenos Acíclicos , Lauraceae , Factores de Transcripción , Factores de Transcripción/genética , Filogenia , Alcohol Deshidrogenasa , Monoterpenos
13.
Drug Resist Updat ; 74: 101085, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38636338

RESUMEN

Enhanced DNA repair is an important mechanism of inherent and acquired resistance to DNA targeted therapies, including poly ADP ribose polymerase (PARP) inhibition. Spleen associated tyrosine kinase (Syk) is a non-receptor tyrosine kinase acknowledged for its regulatory roles in immune cell function, cell adhesion, and vascular development. This study presents evidence indicating that Syk expression in high-grade serous ovarian cancer and triple-negative breast cancers promotes DNA double-strand break resection, homologous recombination (HR), and subsequent therapeutic resistance. Our investigations reveal that Syk is activated by ATM following DNA damage and is recruited to DNA double-strand breaks by NBS1. Once localized to the break site, Syk phosphorylates CtIP, a pivotal mediator of resection and HR, at Thr-847 to promote repair activity, particularly in Syk-expressing cancer cells. Inhibition of Syk or its genetic deletion impedes CtIP Thr-847 phosphorylation and overcomes the resistant phenotype. Collectively, our findings suggest a model wherein Syk fosters therapeutic resistance by promoting DNA resection and HR through a hitherto uncharacterized ATM-Syk-CtIP pathway. Moreover, Syk emerges as a promising tumor-specific target to sensitize Syk-expressing tumors to PARP inhibitors, radiation and other DNA-targeted therapies.


Asunto(s)
Roturas del ADN de Doble Cadena , Resistencia a Antineoplásicos , Recombinación Homóloga , Quinasa Syk , Quinasa Syk/metabolismo , Quinasa Syk/genética , Quinasa Syk/antagonistas & inhibidores , Humanos , Roturas del ADN de Doble Cadena/efectos de los fármacos , Femenino , Resistencia a Antineoplásicos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Fosforilación , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Reparación del ADN/efectos de los fármacos , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Proteínas de la Ataxia Telangiectasia Mutada/antagonistas & inhibidores , Proteínas de la Ataxia Telangiectasia Mutada/genética , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Animales , Línea Celular Tumoral , Daño del ADN/efectos de los fármacos
14.
J Neurosci ; 43(8): 1334-1347, 2023 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-36653189

RESUMEN

Itch is an uncomfortable and complex sensation that elicits the desire to scratch. The nucleus accumbens (NAc) activity is important in driving sensation, motivation, and emotion. Excitatory afferents from the medial prefrontal cortex (mPFC), amygdala, and hippocampus are crucial in tuning the activity of dopamine receptor D1-expressing and D2-expressing medium spiny neurons (Drd1-MSN and Drd2-MSN) in the NAc. However, a cell-type and neural circuity-based mechanism of the NAc underlying acute itch remains unclear. We found that acute itch induced by compound 48/80 (C48/80) decreased the intrinsic membrane excitability in Drd1-MSNs, but not in Drd2-MSNs, in the NAc core of male mice. Chemogenetic activation of Drd1-MSNs alleviated C48/80-induced scratching behaviors but not itch-related anxiety-like behaviors. In addition, C48/80 enhanced the frequency of spontaneous EPSCs (sEPSCs) and reduced the paired-pulse ratio (PPR) of electrical stimulation-evoked EPSCs in Drd1-MSNs. Furthermore, C48/80 increased excitatory synaptic afferents to Drd1-MSNs from the mPFC, not from the basolateral amygdala (BLA) or ventral hippocampus (vHipp). Consistently, the intrinsic excitability of mPFC-NAc projecting pyramidal neurons was increased after C48/80 treatment. Chemogenetic inhibition of mPFC-NAc excitatory synaptic afferents relieved the scratching behaviors. Moreover, pharmacological activation of κ opioid receptor (KOR) in the NAc core suppressed C48/80-induced scratching behaviors, and the modulation of KOR activity in the NAc resulted in the changes of presynaptic excitatory inputs to Drd1-MSNs in C48/80-treated mice. Together, these results reveal the neural plasticity in synapses of NAc Drd1-MSNs from the mPFC underlying acute itch and indicate the modulatory role of the KOR in itch-related scratching behaviors.SIGNIFICANCE STATEMENT Itch stimuli cause strongly scratching desire and anxiety in patients. However, the related neural mechanisms remain largely unclear. In the present study, we demonstrated that the pruritogen compound 48/80 (C48/80) shapes the excitability of dopamine receptor D1-expressing medium spiny neurons (Drd1-MSNs) in the nucleus accumbens (NAc) core and the glutamatergic synaptic afferents from medial prefrontal cortex (mPFC) to these neurons. Chemogenetic activation of Drd1-MSNs or inhibition of mPFC-NAc excitatory synaptic afferents relieves the scratching behaviors. In addition, pharmacological activation of κ opioid receptor (KOR) in the NAc core alleviates C48/80-induced itch. Thus, targeting mPFC-NAc Drd1-MSNs or KOR may provide effective treatments for itch.


Asunto(s)
Núcleo Accumbens , Receptores Opioides kappa , Ratones , Masculino , Animales , Núcleo Accumbens/fisiología , Hipocampo/fisiología , Neuronas/fisiología , Receptores de Dopamina D1/metabolismo , Corteza Prefrontal/metabolismo
15.
J Am Chem Soc ; 146(29): 20391-20400, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38987861

RESUMEN

Inspired by enzymatic catalysis, it is crucial to construct hydrogen-bonding-rich microenvironment around catalytic sites; unfortunately, its precise construction and understanding how the distance between such microenvironment and catalytic sites affects the catalysis remain significantly challenging. In this work, a series of metal-organic framework (MOF)-based single-atom Ru1 catalysts, namely, Ru1/UiO-67-X (X = -H, -m-(NH2)2, -o-(NH2)2), have been synthesized, where the distance between the hydrogen-bonding microenvironment and Ru1 sites is modulated by altering the location of amino groups. The -NH2 group can form hydrogen bonds with H2O, constituting a unique microenvironment that causes an increased water concentration around the Ru1 sites. Remarkably, Ru1/UiO-67-o-(NH2)2 displays a superior photocatalytic hydrogen production rate, ∼4.6 and ∼146.6 times of Ru1/UiO-67-m-(NH2)2 and Ru1/UiO-67, respectively. Both experimental and computational results suggest that the close proximity of amino groups to the Ru1 sites in Ru1/UiO-67-o-(NH2)2 improves charge transfer and H2O dissociation, accounting for the promoted photocatalytic hydrogen production.

16.
Br J Haematol ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-39031781

RESUMEN

Despite significant progress in treating chronic lymphocytic leukaemia (CLL), resistance to therapy remains challenging. NOTCH1 activation, common in CLL, confers adverse prognosis. This study explores the impact of NOTCH1 signalling on venetoclax sensitivity in vitro. Although NOTCH1 activation minimally impaired the susceptibility of CLL cells to venetoclax, ex vivo cell competition studies reveal that cells with constitutive NOTCH1 activation outgrew their wild-type counterparts in the presence of ongoing venetoclax exposure. Our findings suggest that while NOTCH1 activation is insufficient to confer venetoclax refractoriness, there is enhanced potential for cells with NOTCH1 activation to escape and thus become fully resistant to venetoclax.

17.
Anal Chem ; 96(6): 2524-2533, 2024 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-38308578

RESUMEN

Accurate lipid quantification is essential to revealing their roles in physiological and pathological processes. However, difficulties in the structural resolution of lipid isomers hinder their further accurate quantification. To address this challenge, we developed a novel stable-isotope N-Me aziridination strategy that enables simultaneous qualification and quantification of unsaturated lipid isomers. The one-step introduction of the 1-methylaziridine structure not only serves as an activating group for the C═C bond to facilitate positional identification but also as an isotopic inserter to achieve accurate relative quantification. The high performance of this reaction for the identification of unsaturated lipids was verified by large-scale resolution of the C═C positions of 468 lipids in serum. More importantly, by using this bifunctional duplex labeling method, various unsaturated lipids such as fatty acids, phospholipids, glycerides, and cholesterol ester were accurately and individually quantified at the C═C bond isomeric level during the mouse brain ischemia. This study provides a new approach to quantitative structural lipidomics.


Asunto(s)
Ácidos Grasos , Lipidómica , Ratones , Animales , Lipidómica/métodos , Isomerismo , Ácidos Grasos/química , Fosfolípidos/química , Glicéridos
18.
Anal Chem ; 96(25): 10356-10364, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38863415

RESUMEN

Capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C4D) has proven to be an efficient technique for the separation and detection of charged inorganic, organic, and biochemical analytes. It offers several advantages, including cost-effectiveness, nanoliter injection volume, short analysis time, good separation efficiency, suitability for miniaturization, and portability. However, the routine determination of common inorganic cations (NH4+, K+, Na+, Ca2+, Mg2+, and Li+) and inorganic anions (F-, Cl-, Br-, NO2-, NO3-, PO43-, and SO42-) in water quality monitoring typically exhibits limits of detection of about 0.3-1 µM without preconcentration. This sensitivity often proves insufficient for the applications of CE-C4D in trace analysis situations. Here, we explore methods to push the detection limits of CE-C4D through a comprehensive consideration of signal and noise sources. In particular, we (i) studied the model of C4D and its guiding roles in C4D and CE-C4D, (ii) optimized the bandwidth and noise performance of the current-to-voltage (I-V) converter, and (iii) reduced the noise level due to the strong background signal of the background electrolyte by adaptive differential detection. We characterized the system with Li+; the 3-fold signal-to-noise (S/N) detection limit for Li+ was determined at 20 nM, with a linear range spanning from 60 nM to 1.6 mM. Moreover, the optimized CE-C4D method was applied to the analysis of common mixed inorganic cations (K+, Na+, Ca2+, Mg2+, and Li+), anions (F-, Cl-, Br-, NO2-, NO3-, PO43-, and SO42-), toxic halides (BrO3-) and heavy metal ions (Pb2+, Cd2+, Cr3+, Co2+, Ni2+, Zn2+, and Cu2+) at trace concentrations of 200 nM. All electropherograms showed good S/N ratios, thus proving its applicability and accuracy. Our results have shown that the developed CE-C4D method is feasible for trace ion analysis in water quality control.

19.
Bioinformatics ; 39(7)2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37399092

RESUMEN

MOTIVATION: Chromothripsis, associated with poor clinical outcomes, is prognostically vital in multiple myeloma. The catastrophic event is reported to be detectable prior to the progression of multiple myeloma. As a result, chromothripsis detection can contribute to risk estimation and early treatment guidelines for multiple myeloma patients. However, manual diagnosis remains the gold standard approach to detect chromothripsis events with the whole-genome sequencing technology to retrieve both copy number variation (CNV) and structural variation data. Meanwhile, CNV data are much easier to obtain than structural variation data. Hence, in order to reduce the reliance on human experts' efforts and structural variation data extraction, it is necessary to establish a reliable and accurate chromothripsis detection method based on CNV data. RESULTS: To address those issues, we propose a method to detect chromothripsis solely based on CNV data. With the help of structure learning, the intrinsic relationship-directed acyclic graph of CNV features is inferred to derive a CNV embedding graph (i.e. CNV-DAG). Subsequently, a neural network based on Graph Transformer, local feature extraction, and non-linear feature interaction, is proposed with the embedding graph as the input to distinguish whether the chromothripsis event occurs. Ablation experiments, clustering, and feature importance analysis are also conducted to enable the proposed model to be explained by capturing mechanistic insights. AVAILABILITY AND IMPLEMENTATION: The source code and data are freely available at https://github.com/luvyfdawnYu/CNV_chromothripsis.


Asunto(s)
Cromotripsis , Mieloma Múltiple , Humanos , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/genética , Variaciones en el Número de Copia de ADN , Programas Informáticos , Redes Neurales de la Computación
20.
J Transl Med ; 22(1): 720, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103842

RESUMEN

BACKGROUND: Fatigue is one of the most common neurological symptoms reported post coronavirus disease 2019 (COVID-19) infection. In order to establish effective early intervention strategies, more emphasis should be placed on the correlation between fatigue and cortical neurophysiological changes, especially in healthcare workers, who are at a heightened risk of COVID-19 infection. METHODS: A prospective cohort study was conducted involving 29 COVID-19 medical workers and 24 healthy controls. The assessment included fatigue, sleep and health quality, psychological status, and physical capacity. Functional near-infrared spectroscopy (fNIRS) was employed to detect activation of brain regions. Bilateral primary motor cortex (M1) excitabilities were measured using single- and paired-pulse transcranial magnetic stimulation. Outcomes were assessed at 1, 3, and 6 months into the disease course. RESULTS: At 1-month post-COVID-19 infection, 37.9% of patients experienced severe fatigue symptoms, dropping to 10.3% at 3 months. Interestingly, the remarkable decreased activation/excitability of bilateral prefrontal lobe (PFC) and M1 were closely linked to fatigue symptoms after COVID-19. Notably, greater increase in M1 region excitability correlated with more significant fatigue improvement. Re-infected patients exhibited lower levels of brain activation and excitability compared to single-infection patients. CONCLUSIONS: Both single infection and reinfection of COVID-19 lead to decreased activation and excitability of the PFC and M1. The degree of excitability improvement in the M1 region correlates with a greater recovery in fatigue. Based on these findings, targeted interventions to enhance and regulate the excitability of M1 may represent a novel strategy for COVID-19 early rehabilitation. TRIAL REGISTRATION: The Ethics Review Committee of Xijing Hospital, No. KY20232051-F-1; www.chictr.org.cn , ChiCTR2300068444.


Asunto(s)
COVID-19 , Fatiga , Personal de Salud , Corteza Motora , Corteza Prefrontal , Estimulación Magnética Transcraneal , Humanos , COVID-19/fisiopatología , Fatiga/fisiopatología , Masculino , Femenino , Estudios Longitudinales , Adulto , Corteza Prefrontal/fisiopatología , Corteza Prefrontal/diagnóstico por imagen , Corteza Motora/fisiopatología , Persona de Mediana Edad , SARS-CoV-2/aislamiento & purificación , Estudios Prospectivos , Espectroscopía Infrarroja Corta , Estudios de Cohortes
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