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1.
Cell ; 169(4): 664-678.e16, 2017 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-28475895

RESUMEN

Dysregulated rRNA synthesis by RNA polymerase I (Pol I) is associated with uncontrolled cell proliferation. Here, we report a box H/ACA small nucleolar RNA (snoRNA)-ended long noncoding RNA (lncRNA) that enhances pre-rRNA transcription (SLERT). SLERT requires box H/ACA snoRNAs at both ends for its biogenesis and translocation to the nucleolus. Deletion of SLERT impairs pre-rRNA transcription and rRNA production, leading to decreased tumorigenesis. Mechanistically, SLERT interacts with DEAD-box RNA helicase DDX21 via a 143-nt non-snoRNA sequence. Super-resolution images reveal that DDX21 forms ring-shaped structures surrounding multiple Pol I complexes and suppresses pre-rRNA transcription. Binding by SLERT allosterically alters individual DDX21 molecules, loosens the DDX21 ring, and evicts DDX21 suppression on Pol I transcription. Together, our results reveal an important control of ribosome biogenesis by SLERT lncRNA and its regulatory role in DDX21 ring-shaped arrangements acting on Pol I complexes.


Asunto(s)
ARN Helicasas DEAD-box/metabolismo , ARN Polimerasa I/metabolismo , Precursores del ARN/genética , ARN Largo no Codificante/metabolismo , Sitio Alostérico , Animales , Carcinogénesis , Línea Celular , Línea Celular Tumoral , ARN Helicasas DEAD-box/química , Femenino , Técnicas de Inactivación de Genes , Humanos , Ratones , Ratones Desnudos , Precursores del ARN/metabolismo , Transcripción Genética
2.
Nature ; 615(7952): 526-534, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36890225

RESUMEN

The nucleolus is the most prominent membraneless condensate in the nucleus. It comprises hundreds of proteins with distinct roles in the rapid transcription of ribosomal RNA (rRNA) and efficient processing within units comprising a fibrillar centre and a dense fibrillar component and ribosome assembly in a granular component1. The precise localization of most nucleolar proteins and whether their specific localization contributes to the radial flux of pre-rRNA processing have remained unknown owing to insufficient resolution in imaging studies2-5. Therefore, how these nucleolar proteins are functionally coordinated with stepwise pre-rRNA processing requires further investigation. Here we screened 200 candidate nucleolar proteins using high-resolution live-cell microscopy and identified 12 proteins that are enriched towards the periphery of the dense fibrillar component (PDFC). Among these proteins, unhealthy ribosome biogenesis 1 (URB1) is a static, nucleolar protein that ensures 3' end pre-rRNA anchoring and folding for U8 small nucleolar RNA recognition and the subsequent removal of the 3' external transcribed spacer (ETS) at the dense fibrillar component-PDFC boundary. URB1 depletion leads to a disrupted PDFC, uncontrolled pre-rRNA movement, altered pre-rRNA conformation and retention of the 3' ETS. These aberrant 3' ETS-attached pre-rRNA intermediates activate exosome-dependent nucleolar surveillance, resulting in decreased 28S rRNA production, head malformations in zebrafish and delayed embryonic development in mice. This study provides insight into functional sub-nucleolar organization and identifies a physiologically essential step in rRNA maturation that requires the static protein URB1 in the phase-separated nucleolus.


Asunto(s)
Nucléolo Celular , Exosomas , Precursores del ARN , Procesamiento Postranscripcional del ARN , ARN Ribosómico , Pez Cebra , Animales , Ratones , Nucléolo Celular/metabolismo , Desarrollo Embrionario , Exosomas/metabolismo , Cabeza/anomalías , Microscopía , Proteínas Nucleares/metabolismo , Precursores del ARN/metabolismo , ARN Ribosómico/genética , ARN Ribosómico/metabolismo , ARN Ribosómico 28S/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismo
3.
Mol Cell ; 76(5): 767-783.e11, 2019 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-31540874

RESUMEN

Fibrillar centers (FCs) and dense fibrillar components (DFCs) are essential morphologically distinct sub-regions of mammalian cell nucleoli for rDNA transcription and pre-rRNA processing. Here, we report that a human nucleolus consists of several dozen FC/DFC units, each containing 2-3 transcriptionally active rDNAs at the FC/DFC border. Pre-rRNA processing factors, such as fibrillarin (FBL), form 18-24 clusters that further assemble into the DFC surrounding the FC. Mechanistically, the 5' end of nascent 47S pre-rRNA binds co-transcriptionally to the RNA-binding domain of FBL. FBL diffuses to the DFC, where local self-association via its glycine- and arginine-rich (GAR) domain forms phase-separated clusters to immobilize FBL-interacting pre-rRNA, thus promoting directional traffic of nascent pre-rRNA while facilitating pre-rRNA processing and DFC formation. These results unveil FC/DFC ultrastructures in nucleoli and suggest a conceptual framework for considering nascent RNA sorting using multivalent interactions of their binding proteins.


Asunto(s)
Nucléolo Celular/metabolismo , Precursores del ARN/metabolismo , Procesamiento Postranscripcional del ARN , ARN Ribosómico/metabolismo , Transporte Activo de Núcleo Celular , Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Nucléolo Celular/genética , Nucléolo Celular/ultraestructura , Proteínas Cromosómicas no Histona/genética , Proteínas Cromosómicas no Histona/metabolismo , Femenino , Células HEK293 , Células HeLa , Humanos , Conformación de Ácido Nucleico , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Precursores del ARN/genética , Precursores del ARN/ultraestructura , ARN Ribosómico/genética , ARN Ribosómico/ultraestructura
4.
Nucleic Acids Res ; 52(6): 3406-3418, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38412313

RESUMEN

RNA helicases function as versatile enzymes primarily responsible for remodeling RNA secondary structures and organizing ribonucleoprotein complexes. In our study, we conducted a systematic analysis of the helicase-related activities of Escherichia coli HrpA and presented the structures of both its apo form and its complex bound with both conventional and non-canonical DNAs. Our findings reveal that HrpA exhibits NTP hydrolysis activity and binds to ssDNA and ssRNA in distinct sequence-dependent manners. While the helicase core plays an essential role in unwinding RNA/RNA and RNA/DNA duplexes, the N-terminal extension in HrpA, consisting of three helices referred to as the APHB domain, is crucial for ssDNA binding and RNA/DNA duplex unwinding. Importantly, the APHB domain is implicated in binding to non-canonical DNA structures such as G-quadruplex and i-motif, and this report presents the first solved i-motif-helicase complex. This research not only provides comprehensive insights into the multifaceted roles of HrpA as an RNA helicase but also establishes a foundation for further investigations into the recognition and functional implications of i-motif DNA structures in various biological processes.


Asunto(s)
ADN Helicasas , Proteínas de Escherichia coli , Secuencia de Aminoácidos , ADN/química , ADN Helicasas/metabolismo , ADN de Cadena Simple/genética , Escherichia coli/metabolismo , ARN/química , ARN Helicasas/genética , Proteínas de Escherichia coli/metabolismo
5.
Proc Natl Acad Sci U S A ; 119(23): e2116462119, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35658074

RESUMEN

Helicases are multifunctional motor proteins with the primary task of separating nucleic acid duplexes. These enzymes often exist in distinct oligomeric forms and play essential roles during nucleic acid metabolism. Whether there is a correlation between their oligomeric state and cellular function, and how helicases effectively perform functional switching remains enigmatic. Here, we address these questions using a combined single-molecule approach and Bloom syndrome helicase (BLM). By examining the head-on collision of two BLM-mediated DNA unwinding forks, we find that two groups of BLM, upon fork convergence, promptly oligomerize across the fork junctions and tightly bridge two independent single-stranded (ss) DNA molecules that were newly generated by the unwinding BLMs. This protein oligomerization is mediated by the helicase and RNase D C-terminal (HRDC) domain of BLM and can sustain a disruptive force of up to 300 pN. Strikingly, onsite BLM oligomerization gives rise to an immediate transition of their helicase activities, from unwinding dsDNA to translocating along ssDNA at exceedingly fast rates, thus allowing for the efficient displacement of ssDNA-binding proteins, such as RPA and RAD51. These findings uncover an activity transition pathway for helicases and help to explain how BLM plays both pro- and anti-recombination roles in the maintenance of genome stability.


Asunto(s)
ADN de Cadena Simple , RecQ Helicasas , ADN/metabolismo , ADN de Cadena Simple/genética , Recombinación Homóloga , Microscopía Confocal , Pinzas Ópticas , RecQ Helicasas/metabolismo
6.
Nano Lett ; 24(23): 7069-7076, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38808684

RESUMEN

Local cells can actively create reverse bending (evagination) in invaginated epithelia, which plays a crucial role in the formation of elaborate organisms. However, the precise physical mechanism driving the evagination remains elusive. Here, we present a three-dimensional vertex model, incorporating the intrinsic cell polarity, to explore the complex morphogenesis induced by local mechanical modulations. We find that invaginated tissues can spontaneously generate local reverse bending due to the shift of the apicobasal polarity. Their exact shapes can be analytically determined by the local apicobasal differential tension and the internal stress. Our continuum theory exhibits three regions in a phase diagram controlled by these two parameters, showing curvature transitions from ordered to disordered states. Additionally, we delve into epithelial curvature transition induced by the nucleus repositioning, revealing its active contribution to the apicobasal force generation. The uncovered mechanical principles could potentially guide more studies on epithelial folding in diverse systems.


Asunto(s)
Polaridad Celular , Epitelio/fisiología , Polaridad Celular/fisiología , Células Epiteliales/citología , Modelos Biológicos , Morfogénesis , Estrés Mecánico , Animales , Humanos
7.
Nano Lett ; 24(12): 3631-3637, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38466240

RESUMEN

A striking phenomenon of collective cell motion is that they can exhibit a spontaneously emerging wave during epithelia expansions. However, the fundamental mechanism, governing the emergence and its crucial characteristics (e.g., the eigenfrequency and the pattern), remains an enigma. By introducing a mechanochemical feedback loop, we develop a highly efficient discrete vertex model to investigate the spatiotemporal evolution of spreading epithelia. We find both numerically and analytically that expanding cell monolayers display a power-law dependence of wave frequency on the local heterogeneities (i.e., cell density) with a scaling exponent of -1/2. Moreover, our study demonstrates the quantitative capability of the proposed model in capturing distinct X-, W-, and V-mode wave patterns. We unveil that the phase transition between these modes is governed by the distribution of active self-propulsion forces. Our work provides an avenue for rigorous quantitative investigations into the collective motion and pattern formation of cell groups.

8.
Trends Biochem Sci ; 45(11): 947-960, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32800670

RESUMEN

Long noncoding RNAs (lncRNAs) are crucial regulators in diverse cellular contexts and biological processes. The subcellular localization of lncRNAs determines their modes of action. Compared to mRNAs, however, many mRNA-like lncRNAs are preferentially localized to the nucleus where they regulate chromatin organization, transcription, and different nuclear condensates. Recent studies have revealed the complex mechanisms that govern lncRNA nuclear retention. We review current understanding of how the transcription and processing of lncRNAs, motifs within lncRNAs, and trans-factors coordinately contribute to their nuclear retention in mammalian cells.


Asunto(s)
Núcleo Celular/metabolismo , ARN Largo no Codificante/metabolismo , Animales , Núcleo Celular/genética , Cromatina/genética , Cromatina/metabolismo , Humanos , ARN Largo no Codificante/genética
9.
Biophys J ; 123(13): 1869-1881, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38835167

RESUMEN

Cell mechanics are pivotal in regulating cellular activities, diseases progression, and cancer development. However, the understanding of how cellular viscoelastic properties vary in physiological and pathological stimuli remains scarce. Here, we develop a hybrid self-similar hierarchical theory-microrheology approach to accurately and efficiently characterize cellular viscoelasticity. Focusing on two key cell types associated with livers fibrosis-the capillarized liver sinusoidal endothelial cells and activated hepatic stellate cells-we uncover a universal two-stage power-law rheology characterized by two distinct exponents, αshort and αlong. The mechanical profiles derived from both exponents exhibit significant potential for discriminating among diverse cells. This finding suggests a potential common dynamic creep characteristic across biological systems, extending our earlier observations in soft tissues. Using a tailored hierarchical model for cellular mechanical structures, we discern significant variations in the viscoelastic properties and their distribution profiles across different cell types and states from the cytoplasm (elastic stiffness E1 and viscosity η), to a single cytoskeleton fiber (elastic stiffness E2), and then to the cell level (transverse expansion stiffness E3). Importantly, we construct a logistic-regression-based machine-learning model using the dynamic parameters that outperforms conventional cell-stiffness-based classifiers in assessing cell states, achieving an area under the curve of 97% vs. 78%. Our findings not only advance a robust framework for monitoring intricate cell dynamics but also highlight the crucial role of cellular viscoelasticity in discerning cell states across a spectrum of liver diseases and prognosis, offering new avenues for developing diagnostic and therapeutic strategies based on cellular viscoelasticity.


Asunto(s)
Elasticidad , Viscosidad , Fenómenos Biomecánicos , Animales , Células Endoteliales/citología , Células Endoteliales/metabolismo , Células Estrelladas Hepáticas/citología , Células Estrelladas Hepáticas/metabolismo , Reología , Humanos , Modelos Biológicos , Hígado/citología , Aprendizaje Automático
10.
J Biol Chem ; 299(5): 104592, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36894019

RESUMEN

Human DDX5 and its yeast ortholog Dbp2 are ATP-dependent RNA helicases that play a key role in normal cell processes, cancer development, and viral infection. The crystal structure of the RecA1-like domain of DDX5 is available but the global structure of DDX5/Dbp2 subfamily proteins remains to be elucidated. Here, we report the first X-ray crystal structures of the Dbp2 helicase core alone and in complex with ADP at 3.22 Å and 3.05 Å resolutions, respectively. The structures of the ADP-bound post-hydrolysis state and apo-state demonstrate the conformational changes that occur when the nucleotides are released. Our results showed that the helicase core of Dbp2 shifted between open and closed conformation in solution but the unwinding activity was hindered when the helicase core was restricted to a single conformation. A small-angle X-ray scattering experiment showed that the disordered amino (N) tail and carboxy (C) tails are flexible in solution. Truncation mutations confirmed that the terminal tails were critical for the nucleic acid binding, ATPase, and unwinding activities, with the C-tail being exclusively responsible for the annealing activity. Furthermore, we labeled the terminal tails to observe the conformational changes between the disordered tails and the helicase core upon binding nucleic acid substrates. Specifically, we found that the nonstructural terminal tails bind to RNA substrates and tether them to the helicase core domain, thereby conferring full helicase activities to the Dbp2 protein. This distinct structural characteristic provides new insight into the mechanism of DEAD-box RNA helicases.


Asunto(s)
ARN Helicasas DEAD-box , Proteínas de Saccharomyces cerevisiae , Humanos , ARN Helicasas DEAD-box/metabolismo , ARN/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Conformación Molecular , ADN Helicasas/metabolismo
11.
Neuroimage ; 297: 120762, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39089603

RESUMEN

Chronic insomnia (CI) is a complex disease involving multiple factors including genetics, gut microbiota, and brain structure and function. However, there lacks a unified framework to elucidate how these factors interact in CI. By combining data of clinical assessment, sleep behavior recording, cognitive test, multimodal MRI (structural, functional, and perfusion), gene, and gut microbiota, this study demonstrated that enhanced cerebral blood flow (CBF) similarities of the somatomotor network (SMN) acted as a key mediator to link multiple factors in CI. Specifically, we first demonstrated that only CBF but not morphological or functional networks exhibited alterations in patients with CI, characterized by increases within the SMN and between the SMN and higher-order associative networks. Moreover, these findings were highly reproducible and the CBF similarity method was test-retest reliable. Further, we showed that transcriptional profiles explained 60.4 % variance of the pattern of the increased CBF similarities with the most correlated genes enriched in regulation of cellular and protein localization and material transport, and gut microbiota explained 69.7 % inter-individual variance in the increased CBF similarities with the most contributions from Negativicutes and Lactobacillales. Finally, we found that the increased CBF similarities were correlated with clinical variables, accounted for sleep behaviors and cognitive deficits, and contributed the most to the patient-control classification (accuracy = 84.4 %). Altogether, our findings have important implications for understanding the neuropathology of CI and may inform ways of developing new therapeutic strategies for the disease.


Asunto(s)
Circulación Cerebrovascular , Microbioma Gastrointestinal , Imagen por Resonancia Magnética , Trastornos del Inicio y del Mantenimiento del Sueño , Transcriptoma , Humanos , Trastornos del Inicio y del Mantenimiento del Sueño/fisiopatología , Trastornos del Inicio y del Mantenimiento del Sueño/diagnóstico por imagen , Microbioma Gastrointestinal/fisiología , Masculino , Femenino , Adulto , Persona de Mediana Edad , Circulación Cerebrovascular/fisiología , Imagen por Resonancia Magnética/métodos , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiopatología , Fenotipo
12.
Immunology ; 172(2): 295-312, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38453210

RESUMEN

Hyperactivation of the cyclic-GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signalling pathway has been shown to be associated with the development of a variety of inflammatory diseases, and the discovery of an inhibitor of the cGAS-STING signalling pathway holds great promise in the therapeutic interventions. Epimedium flavonoid (EF), a major active ingredient isolated from the medicinal plant Epimedium, has been reported to have good anti-inflammatory activity, but its exact mechanism of action remains unclear. In the present study, we found that EF in mouse bone marrow-derived macrophages (BMDMs), THP-1 (Tohoku Hospital Pediatrics-1) as well as in human peripheral blood mononuclear cells (hPBMC) inhibited the activation of the cGAS-STING signalling pathway, which subsequently led to a decrease in the expression of type I interferon (IFN-ß, CXCL10 and ISG15) and pro-inflammatory cytokines (IL-6 and TNF-α). Mechanistically, EF does not affect STING oligomerization, but inhibits the formation of functional STING signalosome by attenuating the interaction of interferon regulatory factor 3 (IRF3) with STING and TANK-binding kinase 1 (TBK1). Importantly, in vivo experiments, EF has shown promising therapeutic effects on inflammatory diseases mediated by the cGAS-STING pathway, which include the agonist model induced by DMXAA stimulation, the autoimmune inflammatory disease model induced by three prime repair exonuclease 1 (Trex1) deficiency, and the non-alcoholic steatohepatitis (NASH) model induced by a pathogenic amino acid and choline deficiency diet (MCD). To summarize, our study suggests that EF is a potent potential inhibitor component of the cGAS-STING signalling pathway for the treatment of inflammatory diseases mediated by the cGAS-STING signalling pathway.


Asunto(s)
Epimedium , Flavonoides , Proteínas de la Membrana , Nucleotidiltransferasas , Transducción de Señal , Nucleotidiltransferasas/metabolismo , Proteínas de la Membrana/metabolismo , Animales , Transducción de Señal/efectos de los fármacos , Humanos , Ratones , Flavonoides/farmacología , Epimedium/química , Factor 3 Regulador del Interferón/metabolismo , Macrófagos/metabolismo , Macrófagos/inmunología , Macrófagos/efectos de los fármacos , Ratones Endogámicos C57BL , Citocinas/metabolismo , Células THP-1 , Proteínas Serina-Treonina Quinasas/metabolismo , Antiinflamatorios/farmacología , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/efectos de los fármacos
13.
Mol Pain ; : 17448069241260349, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38795338

RESUMEN

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disease characterized by chronic visceral pain with a complex etiology and challenging treatment. Although accumulating evidence supports the involvement of central nervous system sensitization in the development of visceral pain, the precise molecular mechanisms remain incompletely understood. In this study, we highlight the critical regulatory role of lysine-specific demethylase 6B (KDM6B) in the anterior cingulate cortex (ACC) in chronic visceral pain. To simulate clinical IBS conditions, we utilized the neonatal maternal deprivation (NMD) mouse model. Our results demonstrated that NMD induced chronic visceral pain and anxiety-like behaviors in mice. Notably, the protein expression level of KDM6B significantly increased in the ACC of NMD mice, leading to a reduction in the expression level of H32K7me3. Immunofluorescence staining revealed that KDM6B primarily co-localizes with neurons in the ACC, with minimal presence in microglia and astrocytes. Injecting GSK-J4 (a KDM6B-specific inhibitor) into ACC of NMD mice, resulted in a significant alleviation in chronic visceral pain and anxiety-like behaviors, as well as a remarkable reduction in NR2B expression level. ChIP assay further indicated that KDM6B regulates NR2B expression by influencing the demethylation of H3K27me3. In summary, our findings underscore the critical role of KDM6B in regulating chronic visceral pain and anxiety-like behaviors in NMD mice. These insights provide a basis for further understanding the molecular pathways involved in IBS and may pave the way for targeted therapeutic interventions.

14.
Curr Issues Mol Biol ; 46(3): 1851-1864, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38534737

RESUMEN

Autism spectrum disorder (ASD) is thought to result from susceptibility genotypes and environmental risk factors. The offspring of women who experience pregnancy infection have an increased risk for autism. Maternal immune activation (MIA) in pregnant animals produces offspring with autistic behaviors, making MIA a useful model for autism. However, how MIA causes autistic behaviors in offspring is not fully understood. Here, we show that NKCC1 is critical for mediating autistic behaviors in MIA offspring. We confirmed that MIA induced by poly(I:C) infection during pregnancy leads to autistic behaviors in offspring. We further demonstrated that MIA offspring showed significant microglia activation, excessive dendritic spines, and narrow postsynaptic density (PSD) in their prefrontal cortex (PFC). Then, we discovered that these abnormalities may be caused by overexpression of NKCC1 in MIA offspring's PFCs. Finally, we ameliorated the autistic behaviors using PFC microinjection of NKCC1 inhibitor bumetanide (BTN) in MIA offspring. Our findings may shed new light on the pathological mechanisms for autism caused by pregnancy infection.

15.
Eur J Neurosci ; 59(11): 3045-3060, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38576168

RESUMEN

Dual tasks (DTs) combining walking with a cognitive task can cause various levels of cognitive-motor interference, depending on which brain resources are recruited in each case. However, the brain activation and functional connectivity underlying cognitive-motor interferences remain to be elucidated. Therefore, this study investigated the neural correlation during different DT conditions in 40 healthy young adults (mean age: 27.53 years, 28 women). The DTs included walking during subtraction or N-Back tasks. Cognitive-motor interference was calculated, and brain activation and functional connectivity were analysed. Portable functional near-infrared spectroscopy was utilized to monitor haemodynamics in the prefrontal cortex (PFC), motor cortex and parietal cortex during each task. Walking interference (decrease in walking speed during DT) was greater than cognitive interference (decrease in cognitive performance during DT), regardless of the type of task. Brain activation in the bilateral PFC and parietal cortex was greater for walking during subtraction than for standing subtraction. Furthermore, brain activation was higher in the bilateral motor and parietal and PFCs for walking during subtraction than for walking alone, but only increased in the PFC for walking during N-Back. Coherence between the bilateral lateral PFC and between the left lateral PFC and left motor cortex was significantly greater for walking during 2-Back than for walking. The PFC, a critical brain region for organizing cognitive and motor functions, played a crucial role in integrating information coming from multiple brain networks required for completing DTs. Therefore, the PFC could be a potential target for the modulation and improvement of cognitive-motor functions during neurorehabilitation.


Asunto(s)
Cognición , Desempeño Psicomotor , Espectroscopía Infrarroja Corta , Humanos , Femenino , Espectroscopía Infrarroja Corta/métodos , Masculino , Adulto , Cognición/fisiología , Desempeño Psicomotor/fisiología , Adulto Joven , Caminata/fisiología , Corteza Motora/fisiología , Corteza Prefrontal/fisiología , Corteza Prefrontal/diagnóstico por imagen , Lóbulo Parietal/fisiología
16.
Small ; 20(10): e2306341, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37903360

RESUMEN

Pd-based electrocatalysts are the most effective catalysts for ethylene glycol oxidation reaction (EGOR), while the disadvantages of poor stability, low resistance to neutrophilic, and low catalytic activity seriously hamper the development of direct ethylene glycol fuel cells (DEGFCs). In this work, defect-riched PdCoZn nanosheets (D-PdCoZn NSs) with ultrathin 2D NSs and porous structures are fabricated through the solvothermal and alkali etching processes. Benefiting from the presence of defects and ultrathin 2D structures, D-PdCoZn NSs demonstrate excellent electrocatalytic activity and good durability against EGOR in alkaline media. The mass activity and specific activity of D-PdCoZn NSs for EGOR are 9.5 A mg-1 and 15.7 mA cm-2 , respectively, which are higher than that of PdCoZn NSs, PdCo NSs, and Pd black. The D-PdCoZn NSs still maintain satisfactory mass activity after long-term durability tests. Meanwhile, in situ IR spectroscopy demonstrates that the presence of defects attenuated the adsorption of intermediates, which improves the selectivity of the C1 pathway with excellent anti-CO poisoning performance. This work not only provides an effective synthetic strategy for the preparation of Pd-based nanomaterials with defective structures but also indicates significant guidance for optimum C1 pathway selectivity of ethylene glycol and other challenging chemical transformations.

17.
Small ; : e2404858, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39279606

RESUMEN

Seawater electrolysis is the most promising technology for hydrogen production, in which surface reconstruction on the interface of electrode/electrolyte plays a crucial role in activating the catalytic reactions with a low activation energy barrier. Herein, an efficient Mo modifying NiCoMo prickly flower clusters electrocatalyst supported on nickel foam (Mo-doped Ni/Co-OOH prickly flower clusters) is obtained, which serves as an eminently active and durable catalyst for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) due to the surface reconstruction during the alkaline seawater electrolysis with ultralow overpotentials. It just requires a cell voltage of 1.52 V to achieve the current density of 10 mA cm-2 for water electrolysis along with robust durability over 30 h. Mo doping effectively regulates the surface reconstruction of Ni/Co-OOH, which facilitates the adsorption of oxygen-containing intermediates on the active center, and the nonhomogeneous interface induces charge rearrangement for the catalytic process to improve efficiency, providing a new strategy for revealing the seawater electrolytic mechanism.

18.
J Med Virol ; 96(8): e29842, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39115036

RESUMEN

To explore the impacts of cytomegalovirus (CMV) infection and antiviral treatment (AVT) on native liver survival (NLS) in biliary atresia (BA) infants. This retrospective cohort study included infants diagnosed as BA between January 2015 and December 2021 at Hunan Children's Hospital. CMV infection was defined by DNA polymerase chain reaction alone (DNA data set) and combination of DNA and immunoglobulin M (CMV data set). In the DNA data set of 330 patients, 234 patients (70.9%) survived with their native liver in 2 years, with 113 (73.9%) in the DNA- cohort, 70 (65.4%) in the DNA+ and AVT- cohort and 51 (72.9%) in the DNA+ and AVT+ cohort, without significant differences by log-rank tests. In patients administrated between 2015 and March 2019, there were 206 evaluable patients in the DNA data set, with rates of 5-year NLS of 68.3% in the DNA- cohort, similar to that in the DNA+ and AVT+ cohort (62.2%, p = 0.546), but significantly higher than that in the DNA+ and AVT- cohort (51.4%, p = 0.031). Similar trends were also observed in the CMV data set, although statistically insignificant. CMV infection before or on the day of HPE can reduce the rate of 5-year NLS and AVT was recommended for CMV-infected BA infants.


Asunto(s)
Antivirales , Atresia Biliar , Infecciones por Citomegalovirus , Citomegalovirus , Humanos , Infecciones por Citomegalovirus/tratamiento farmacológico , Infecciones por Citomegalovirus/virología , Estudios Retrospectivos , Atresia Biliar/tratamiento farmacológico , Antivirales/uso terapéutico , Femenino , Masculino , Lactante , Citomegalovirus/genética , Citomegalovirus/efectos de los fármacos , Pronóstico , ADN Viral , Recién Nacido
19.
BMC Cancer ; 24(1): 88, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38229045

RESUMEN

BACKGROUND: Recently, with the advancement of medical technology, the postoperative morbidity of pelvic exenteration (PE) has gradually decreased, and it has become a curative treatment option for some patients with recurrent gynecological malignancies. However, more evidence is still needed to support its efficacy. This study aimed to explore the safety and long-term survival outcome of PE and the feasibility of umbilical single-port laparoscopic PE for gynecologic malignancies in a single medical center in China. PATIENTS AND METHODS: PE for gynecological cancers except for ovarian cancer conducted by a single surgical team in Sun Yat-sen University Cancer Center between July 2014 and December 2019 were included and the data were retrospectively analyzed. RESULTS: Forty-one cases were included and median age at diagnosis was 53 years. Cervical cancer accounted for 87.8% of all cases, and most of them received prior treatment (95.1%). Sixteen procedures were performed in 2016 and before, and 25 after 2016. Three anterior PE were performed by umbilical single-site laparoscopy. The median operation time was 460 min, and the median estimated blood loss was 600 ml. There was no perioperative death. The years of the operations was significantly associated with the length of the operation time (P = 0.0018). The overall morbidity was 52.4%, while the severe complications rate was 19.0%. The most common complication was pelvic and abdominal infection. The years of surgery was also significantly associated with the occurrence of severe complication (P = 0.040). The median follow-up time was 55.8 months. The median disease-free survival (DFS) was 17.9 months, and the median overall survival (OS) was 25.3 months. The 5-year DFS was 28.5%, and the 5-year OS was 30.8%. CONCLUSION: PE is safe for patient who is selected by a multi-disciplinary treatment, and can be a curative treatment for some patients. PE demands a high level of experience from the surgical team. Umbilical single-port laparoscopy was a technically feasible approach for APE, meriting further investigation.


Asunto(s)
Neoplasias de los Genitales Femeninos , Neoplasias Ováricas , Exenteración Pélvica , Neoplasias del Cuello Uterino , Humanos , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Exenteración Pélvica/efectos adversos , Exenteración Pélvica/métodos , Neoplasias del Cuello Uterino/cirugía , Neoplasias del Cuello Uterino/etiología , Neoplasias Ováricas/cirugía , Neoplasias Ováricas/etiología , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/cirugía , Recurrencia Local de Neoplasia/etiología
20.
Am J Nephrol ; 55(1): 1-17, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37793348

RESUMEN

BACKGROUND: Mineralocorticoid receptor blockade could be a potential approach for the inhibition of chronic kidney disease (CKD) progression. The benefits and harms of different mineralocorticoid receptor antagonists (MRAs) in CKD are inconsistent. OBJECTIVES: The aim of the study was to summarize the benefits and harms of MRAs for CKD patients. METHODS: We searched MEDLINE, EMBASE, and the Cochrane databases for trials assessing the effects of MRAs on non-dialysis-dependent CKD populations. Treatment and adverse effects were summarized using meta-analysis. RESULTS: Fifty-three trials with 6 different MRAs involving 22,792 participants were included. Compared with the control group, MRAs reduced urinary albumin-to-creatinine ratio (weighted mean difference [WMD], -90.90 mg/g, 95% CI, -140.17 to -41.64 mg/g), 24-h urinary protein excretion (WMD, -0.20 g, 95% CI, -0.28 to -0.12 g), estimated glomerular filtration rate (eGFR) (WMD, -1.99 mL/min/1.73 m2, 95% CI, -3.28 to -0.70 mL/min/1.73 m2), chronic renal failure events (RR, 0.86, 95% CI, 0.79-0.93), and cardiovascular events (RR, 0.84, 95% CI, 0.77-0.92). MRAs increased the incidence of hyperkalemia (RR, 2.04, 95% CI, 1.73-2.40) and hypotension (RR, 1.80, 95% CI, 1.41-2.31). MRAs reduced the incidence of peripheral edema (RR, 0.65, 95% CI, 0.56-0.75) but not the risk of acute kidney injury (RR, 0.94, 95% CI, 0.79-1.13). Nonsteroidal MRAs (RR, 0.66, 95% CI, 0.57-0.75) but not steroidal MRAs (RR, 0.20, 95% CI, 0.02-1.68) significantly reduced the risk of peripheral edema. Steroidal MRAs (RR, 5.68, 95% CI, 1.26-25.67) but not nonsteroidal MRAs (RR, 0.52, 95% CI, 0.22-1.22) increased the risk of breast disorders. CONCLUSIONS: In the CKD patients, MRAs, particularly in combination with angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, reduced albuminuria/proteinuria, eGFR, and the incidence of chronic renal failure, cardiovascular and peripheral edema events, whereas increasing the incidence of hyperkalemia and hypotension, without the augment of acute kidney injury events. Nonsteroidal MRAs were superior in the reduction of more albuminuria with fewer peripheral edema events and without the augment of breast disorder events.


Asunto(s)
Lesión Renal Aguda , Hiperpotasemia , Hipotensión , Fallo Renal Crónico , Insuficiencia Renal Crónica , Humanos , Antagonistas de Receptores de Mineralocorticoides/efectos adversos , Hiperpotasemia/inducido químicamente , Hiperpotasemia/epidemiología , Albuminuria/inducido químicamente , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/inducido químicamente , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/epidemiología , Edema
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