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1.
Nature ; 626(7998): 288-293, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38326594

RESUMEN

The microscopic origin of high-temperature superconductivity in cuprates remains unknown. It is widely believed that substantial progress could be achieved by better understanding of the pseudogap phase, a normal non-superconducting state of cuprates1,2. In particular, a central issue is whether the pseudogap could originate from strong pairing fluctuations3. Unitary Fermi gases4,5, in which the pseudogap-if it exists-necessarily arises from many-body pairing, offer ideal quantum simulators to address this question. Here we report the observation of a pair-fluctuation-driven pseudogap in homogeneous unitary Fermi gases of lithium-6 atoms, by precisely measuring the fermion spectral function through momentum-resolved microwave spectroscopy and without spurious effects from final-state interactions. The temperature dependence of the pairing gap, inverse pair lifetime and single-particle scattering rate are quantitatively determined by analysing the spectra. We find a large pseudogap above the superfluid transition temperature. The inverse pair lifetime exhibits a thermally activated exponential behaviour, uncovering the microscopic virtual pair breaking and recombination mechanism. The obtained large, temperature-independent single-particle scattering rate is comparable with that set by the Planckian limit6. Our findings quantitatively characterize the pseudogap in strongly interacting Fermi gases and they lend support for the role of preformed pairing as a precursor to superfluidity.

2.
Mol Cell ; 74(3): 466-480.e4, 2019 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-30930055

RESUMEN

The mTOR pathway integrates both extracellular and intracellular signals and serves as a central regulator of cell metabolism, growth, survival, and stress responses. Neurotropic viruses, such as herpes simplex virus-1 (HSV-1), also rely on cellular AKT-mTORC1 signaling to achieve viral latency. Here, we define a novel genotoxic response whereby spatially separated signals initiated by extracellular neurotrophic factors and nuclear DNA damage are integrated by the AKT-mTORC1 pathway. We demonstrate that endogenous DNA double-strand breaks (DSBs) mediated by Topoisomerase 2ß-DNA cleavage complex (TOP2ßcc) intermediates are required to achieve AKT-mTORC1 signaling and maintain HSV-1 latency in neurons. Suppression of host DNA-repair pathways that remove TOP2ßcc trigger HSV-1 reactivation. Moreover, perturbation of AKT phosphorylation dynamics by downregulating the PHLPP1 phosphatase led to AKT mis-localization and disruption of DSB-induced HSV-1 reactivation. Thus, the cellular genome integrity and environmental inputs are consolidated and co-opted by a latent virus to balance lifelong infection with transmission.


Asunto(s)
ADN-Topoisomerasas de Tipo II/genética , Herpesvirus Humano 1/genética , Proteínas Nucleares/genética , Proteínas Proto-Oncogénicas c-akt/genética , Latencia del Virus/genética , Animales , Roturas del ADN de Doble Cadena , Daño del ADN/genética , Reparación del ADN por Unión de Extremidades/genética , Reparación del ADN/genética , Enzimas Reparadoras del ADN/genética , Proteínas de Unión al ADN/genética , Herpesvirus Humano 1/patogenicidad , Humanos , Proteína Homóloga de MRE11/genética , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Neuronas/metabolismo , Neuronas/virología , Fosforilación , Ratas , Transducción de Señal/genética , Serina-Treonina Quinasas TOR/genética
3.
Nat Immunol ; 15(7): 667-75, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24859450

RESUMEN

CD4(+) follicular helper T cells (T(FH) cells) are essential for germinal center (GC) responses and long-lived antibody responses. Here we report that naive CD4(+) T cells deficient in the transcription factor Foxp1 'preferentially' differentiated into T(FH) cells, which resulted in substantially enhanced GC and antibody responses. We found that Foxp1 used both constitutive Foxp1A and Foxp1D induced by stimulation of the T cell antigen receptor (TCR) to inhibit the generation of T(FH) cells. Mechanistically, Foxp1 directly and negatively regulated interleukin 21 (IL-21); Foxp1 also dampened expression of the costimulatory molecule ICOS and its downstream signaling at early stages of T cell activation, which rendered Foxp1-deficient CD4(+) T cells partially resistant to blockade of the ICOS ligand (ICOSL) during T(FH) cell development. Our findings demonstrate that Foxp1 is a critical negative regulator of T(FH) cell differentiation.


Asunto(s)
Diferenciación Celular , Factores de Transcripción Forkhead/fisiología , Proteínas Represoras/fisiología , Linfocitos T Colaboradores-Inductores/citología , Animales , Linfocitos T CD4-Positivos/inmunología , Proteína Coestimuladora de Linfocitos T Inducibles/genética , Interleucinas/genética , Ratones , Ratones Endogámicos C57BL , Receptores de Antígenos de Linfocitos T/fisiología
4.
J Virol ; : e0033424, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38829137

RESUMEN

Porcine deltacoronavirus (PDCoV) is an enteric pathogenic coronavirus that causes acute and severe watery diarrhea in piglets and has the ability of cross-species transmission, posing a great threat to swine production and public health. The interferon (IFN)-mediated signal transduction represents an important component of virus-host interactions and plays an essential role in regulating viral infection. Previous studies have suggested that multifunctional viral proteins encoded by coronaviruses antagonize the production of IFN via various means. However, the function of these viral proteins in regulating IFN-mediated signaling pathways is largely unknown. In this study, we demonstrated that PDCoV and its encoded nucleocapsid (N) protein antagonize type I IFN-mediated JAK-STAT signaling pathway. We identified that PDCoV infection stimulated but delayed the production of IFN-stimulated genes (ISGs). In addition, PDCoV inhibited JAK-STAT signal transduction by targeting the nuclear translocation of STAT1 and ISGF3 formation. Further evidence showed that PDCoV N is the essential protein involved in the inhibition of type I IFN signaling by targeting STAT1 nuclear translocation via its C-terminal domain. Mechanistically, PDCoV N targets STAT1 by interacting with it and subsequently inhibiting its nuclear translocation. Furthermore, PDCoV N inhibits STAT1 nuclear translocation by specifically targeting KPNA2 degradation through the lysosomal pathway, thereby inhibiting the activation of downstream sensors in the JAK-STAT signaling pathway. Taken together, our results reveal a novel mechanism by which PDCoV N interferes with the host antiviral response.IMPORTANCEPorcine deltacoronavirus (PDCoV) is a novel enteropathogenic coronavirus that receives increased attention and seriously threatens the pig industry and public health. Understanding the underlying mechanism of PDCoV evading the host defense during infection is essential for developing targeted drugs and effective vaccines against PDCoV. This study demonstrated that PDCoV and its encoded nucleocapsid (N) protein antagonize type I interferon signaling by targeting STAT1, which is a crucial signal sensor in the JAK-STAT signaling pathway. Further experiments suggested that PDCoV N-mediated inhibition of the STAT1 nuclear translocation involves the degradation of KPNA2, and the lysosome plays a role in KPNA2 degradation. This study provides new insights into the regulation of PDCoV N in the JAK-STAT signaling pathway and reveals a novel mechanism by which PDCoV evades the host antiviral response. The novel findings may guide us to discover new therapeutic targets and develop live attenuated vaccines for PDCoV infection.

5.
J Immunol ; 211(12): 1756-1761, 2023 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-37888952

RESUMEN

CXCR5 is a hallmark of T follicular helper (Tfh) cells. The mechanism of CXCR5 induction, however, is still incompletely understood. In this study, we report that in mice with the absence of transcription factor Bach2, the Th17-inducing cytokines IL-6 and TGF-ß together induced CXCR5 expression in vitro. Mechanistically, IL-6/STAT3 drove Cxcr5 promoter activity via the upstream site 1 regulatory element, whereas TGF-ß enhanced permissive histone modifications, and the STAT3 binding to the site 1 regulatory element was higher in the absence of Bach2. Subsequently, despite previous studies showing enhanced Th17 cell differentiation in the absence of Bach2 in vitro, we found that in vivo, the Bach2 deficiency led to an enhanced Tfh cell response at the expense of the Th17 cell response. These findings suggest that Bach2 helps integrate cytokine signals to arbitrate differentiation decisions between Tfh and Th17 lineages.


Asunto(s)
Citocinas , Células Th17 , Ratones , Animales , Citocinas/metabolismo , Linfocitos T Colaboradores-Inductores/metabolismo , Interleucina-6/metabolismo , Diferenciación Celular , Factor de Crecimiento Transformador beta/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo
6.
Nucleic Acids Res ; 51(D1): D39-D45, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36268869

RESUMEN

Transcription factors (TFs) are proteins that interact with specific DNA sequences to regulate gene expression and play crucial roles in all kinds of biological processes. To keep up with new data and provide a more comprehensive resource for TF research, we updated the Animal Transcription Factor Database (AnimalTFDB) to version 4.0 (http://bioinfo.life.hust.edu.cn/AnimalTFDB4/) with up-to-date data and functions. We refined the TF family rules and prediction pipeline to predict TFs in genome-wide protein sequences from Ensembl. As a result, we predicted 274 633 TF genes and 150 726 transcription cofactor genes in AnimalTFDB 4.0 in 183 animal genomes, which are 86 more species than AnimalTFDB 3.0. Besides double data volume, we also added the following new annotations and functions to the database: (i) variations (including mutations) on TF genes in various human cancers and other diseases; (ii) predicted post-translational modification sites (including phosphorylation, acetylation, methylation and ubiquitination sites) on TFs in 8 species; (iii) TF regulation in autophagy; (iv) comprehensive TF expression annotation for 38 species; (v) exact and batch search functions allow users to search AnimalTFDB flexibly. AnimalTFDB 4.0 is a useful resource for studying TF and transcription regulation, which contains comprehensive annotation and classification of TFs and transcription cofactors.


Asunto(s)
Bases de Datos Genéticas , Regulación de la Expresión Génica , Factores de Transcripción , Animales , Humanos , Bases de Datos de Proteínas , Anotación de Secuencia Molecular , Factores de Transcripción/metabolismo
7.
PLoS Genet ; 18(9): e1010424, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36129930

RESUMEN

In most plants, sucrose, a major storage sugar, is transported into sink organs to support their growth. This key physiological process is dependent on the function of sucrose transporters. Sucrose export from source tissues is predominantly controlled through the activity of SUCROSE TRANSPORTER 2 (SUC2), required for the loading of sucrose into the phloem of Arabidopsis plants. However, how SUC2 activity is controlled to support root growth remains unclear. Glucose is perceived via the function of HEXOKINASE 1 (HXK1), the only known nuclear glucose sensor. HXK1 negatively regulates the stability of ETHYLENE-INSENSITIVE3 (EIN3), a key ethylene/glucose interaction component. Here we show that HXK1 functions upstream of EIN3 in the regulation of root sink growth mediated by glucose signaling. Furthermore, the transcription factor EIN3 directly inhibits SUC2 activity by binding to the SUC2 promoter, regulating glucose signaling linked to root sink growth. We demonstrate that these molecular components form a HXK1-EIN3-SUC2 module integral to the control of root sink growth. Also, we demonstrate that with increasing age, the HXK1-EIN3-SUC2 module promotes sucrose phloem loading in source tissues thereby elevating sucrose levels in sink roots. As a result, glucose signaling mediated-sink root growth is facilitated. Our findings thus establish a direct molecular link between the HXK1-EIN3-SUC2 module, the source-to sink transport of sucrose and root growth.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Proteínas de Unión al ADN/metabolismo , Etilenos/metabolismo , Regulación de la Expresión Génica de las Plantas , Glucosa/metabolismo , Hexoquinasa/genética , Hexoquinasa/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Hojas de la Planta , Plantas/metabolismo , Sacarosa/metabolismo , Factores de Transcripción/genética
8.
J Am Chem Soc ; 146(8): 5316-5323, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38364304

RESUMEN

Efficient synthesis of enantioenriched amines is of great importance due to their significant synthetic and biological applications. Photoredox-mediated asymmetric α-amino C(sp3)-H functionalization offers an atom-economical and sustainable approach to access chiral amines. However, the development of analogous reactions is in its early stages, generally affording chiral amines with a single stereocenter. Herein, we present a novel synergistic triple-catalysis approach for the asymmetric α-C-H addition of readily available N-sulfonyl amines to aldehydes under mild conditions. This method allows for the efficient synthesis of a diverse array of valuable ß-amino alcohols bearing vicinal stereocenters. Unlike previous reports, our protocol employs a radical approach using earth-abundant Cr catalysis. Quinuclidine plays a dual role by facilitating highly selective hydrogen-atom transfer to generate α-amino radicals and promoting the dissociation of the Cr-O bond, which is crucial for the overall catalytic cycle as evidenced by control, NMR, and DFT experiments. Preliminary mechanistic studies, including radical trapping, nonlinear effect, Stern-Volmer plot, kinetic isotope effect, and Hammett plot, offer valuable insights into the reaction pathway.

9.
BMC Plant Biol ; 24(1): 38, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38191321

RESUMEN

Milling quality (MQ) and grain shape (GS) of rice (Oryza sativa L.) are correlated traits, both determine farmers' final profit. More than one population under multiple environments may provide valuable information for breeding selection on these MQ-GS correlations. However, suitable analytical methods for reciprocal introgression lines with linkage map for this kind of correlation remains unclear. In this study, our major tasks were (1) to provide a set of reciprocal introgression lines (composed of two BC2RIL populations) suitable for mapping by linkage mapping using markers/bins with physical positions; (2) to test the mapping effects of different methods by using MQ-GS correlation dissection as sample case; (3) to perform genetic and breeding simulation on pyramiding favorite alleles of QTLs for representative MQ-GS traits. Finally, with four analysis methods and data collected under five environments, we identified about 28.4 loci on average for MQ-GS traits. Notably, 52.3% of these loci were commonly detected by different methods and eight loci were novel. There were also nine regions harboring loci for different MQ-GS traits which may be underlying the MQ-GS correlations. Background independent (BI) loci were also found for each MQ and GS trait. All these information may provide useful resources for rice molecular breeding.


Asunto(s)
Oryza , Oryza/genética , Fitomejoramiento , Sitios de Carácter Cuantitativo/genética , Mapeo Cromosómico , Alelos , Grano Comestible/genética
10.
Appl Environ Microbiol ; 90(2): e0201623, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38214515

RESUMEN

Global warming has led to a high incidence of extreme heat events, and the frequent occurrence of extreme heat events has had extensive and far-reaching impacts on wetland ecosystems. The widespread distribution of plastics in the environment, including polyethylene (PE), polylactic acid (PLA), and tire particles (TPs), has caused various environmental problems. Here, high-throughput sequencing techniques and metabolomics were used for the first time to investigate the effects of three popular microplastic types: PE, PLA, and TP, on the sediment microbiome and the metabolome at both temperatures. The microplastics were incorporated into the sediment at a concentration of 3% by weight of the dry sediment (wt/wt), to reflect environmentally relevant conditions. Sediment enzymatic activity and physicochemical properties were co-regulated by both temperatures and microplastics producing significant differences compared to controls. PE and PLA particles inhibited bacterial diversity at low temperatures and promoted bacterial diversity at high temperatures, and TP particles promoted both at both temperatures. For bacterial richness, only PLA showed inhibition at low temperature; all other treatments showed promotion. PE, PLA, and TP microplastics changed the community structure of sediment bacteria, forming two clusters at low and high temperatures. Furthermore, PE, PLA, and TP changed the sediment metabolic profiles, producing differential metabolites such as lipids and molecules, organic heterocyclic compounds, and organic acids and their derivatives, especially TP had the most significant effect. These findings contribute to a more comprehensive understanding of the potential impact of microplastic contamination.IMPORTANCEIn this study, we added 3% (wt/wt) microplastic particles, including polyethylene, polylactic acid, and tire particles, to natural sediments under simulated laboratory conditions. Subsequently, we simulated the sediment microbial and ecosystem responses under different temperature conditions by incubating them for 60 days at 15°C and 35°C, respectively. After synthesizing these results, our study strongly suggests that the presence of microplastics in sediment ecosystems and exposure under different temperature conditions may have profound effects on soil microbial communities, enzyme activities, and metabolite profiles. This is important for understanding the potential hazards of microplastic contamination on terrestrial ecosystems and for developing relevant environmental management strategies.


Asunto(s)
Microbiota , Contaminantes Químicos del Agua , Plásticos , Microplásticos/química , Microplásticos/farmacología , Polietileno/análisis , Polietileno/farmacología , Ecosistema , Temperatura , Contaminantes Químicos del Agua/análisis , Sedimentos Geológicos/microbiología , Poliésteres , Metaboloma , Monitoreo del Ambiente
11.
Opt Lett ; 49(5): 1297-1300, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38426997

RESUMEN

The successful demonstration of long-lived nitric oxide (NO) fluorescence for molecular tagging velocimetry (MTV) measurements is described in this Letter. Using 1 + 1 resonance-enhanced multiphoton ionization (REMPI) of NO at a wavelength near 226 nm, targeting the overlapping Q1(7) and Q21(7) lines of the A-X (0, 0) electronic system, the lifetime of the NO MTV signal was observed to be approximately 8.6 µs within a 100-Torr cell containing 2% NO in nitrogen. This is in stark contrast to the commonly reported single photon NO fluorescence, which has a much shorter calculated lifetime of approximately 43 ns at this pressure and NO volume fraction. While the shorter lifetime fluorescence can be useful for molecular tagging velocimetry with single laser excitation within very high-speed flows at some thermodynamic conditions, the longer lived fluorescence shows the potential for an order of magnitude more accurate and precise velocimetry, particularly within lower speed regions of hypersonic flow fields such as wakes and boundary layers. The physical mechanism responsible for the generation of this long-lived signal is detailed. Furthermore, the effectiveness of this technique is showcased in a high-speed jet flow, where it is employed for precise flow velocity measurements.

12.
J Magn Reson Imaging ; 59(5): 1787-1797, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37671487

RESUMEN

BACKGROUND: A referenced MRI-based classification associated with focused ultrasound ablation surgery (FUAS) outcomes is lacking in adenomyosis. PURPOSE: To identify an MRI-based classification system for informing the FUAS outcomes. STUDY TYPE: Retrospective. POPULATION: Patients with FUAS for adenomyosis, were divided into a training set (N = 643; 355 with post-FUAS gonadotropin-releasing hormone/levonorgestrel, 288 without post-FUAS therapy) and an external validation set (N = 135; all without post-FUAS therapy). FIELD STRENGTH/SEQUENCE: 1.5 T, turbo spin-echo T2-weighted imaging and single-shot echo-planar diffusion-weighted imaging sequences. ASSESSMENT: Five MRI-based adenomyosis classifications: classification 1 (C1) (diffuse, focal, and mild), C2 (intrinsic, extrinsic, intramural, and indeterminate), C3 (internal, adenomyomas, and external), C4 (six subtypes on areas [internal or external] and volumes [<1/3 or ≥2/3]), and C5 (internal [asymmetric or symmetric], external, intramural, full thickness [asymmetric or symmetric]) for FUAS outcomes (symptom relief and recurrence). STATISTICAL TESTS: The optimal classification was significantly associated with the most subtypes of FUAS outcomes. Relating to the timing of recurrence was measured using Cox regression analysis and median recurrence time was estimated by a Kaplan-Meier curve. A P value <0.05 was considered statistically significant. RESULTS: Dysmenorrhea relief and recurrence were only associated with C2 in training patients undergoing FUAS alone. Compared with other subtypes, the extrinsic subtype of C2 was significantly associated with dysmenorrhea recurrence in the FUAS group. Besides, the median dysmenorrhea recurrence time of extrinsic subtype was significantly shorter than that of other subtypes (42.0 months vs. 50.3 months). In the validation cohort, C2 was confirmed as the optimal system and its extrinsic subtype was confirmed to have a significantly shorter dysmenorrhea recurrence time than other subtypes. DATA CONCLUSION: Classification 2 can inform dysmenorrhea relief and recurrence in patients with adenomyosis undergoing FAUS only. Itsextrinsic subtype was associated with an earlier onset of dysmenorrhea recurrence after treatment. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 5.


Asunto(s)
Adenomiosis , Ultrasonido Enfocado de Alta Intensidad de Ablación , Femenino , Humanos , Adenomiosis/diagnóstico por imagen , Adenomiosis/cirugía , Dismenorrea/diagnóstico por imagen , Dismenorrea/complicaciones , Dismenorrea/cirugía , Resultado del Tratamiento , Estudios Retrospectivos , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Imagen por Resonancia Magnética/métodos , Ultrasonografía Intervencional/métodos
13.
Brain Behav Immun ; 115: 143-156, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37848095

RESUMEN

Growing evidence suggests that neurovascular dysfunction characterized by blood-brain barrier (BBB) breakdown underlies the development of psychiatric disorders, such as major depressive disorder (MDD). Tight junction (TJ) proteins are critical modulators of homeostasis and BBB integrity. TJ protein Claudin-5 is the most dominant BBB component and is downregulated in numerous depression models; however, the underlying mechanisms remain elusive. Here, we demonstrate a molecular basis of BBB breakdown that links stress and depression. We implemented an animal model of depression, chronic unpredictable mild stress (CUMS) in male C57BL/6 mice, and showed that hippocampal BBB breakdown was closely associated with stress vulnerability. Concomitantly, we found that dysregulated Cldn5 level coupled with repression of the histone methylation signature at its promoter contributed to stress-induced BBB dysfunction and depression. Moreover, histone methyltransferase enhancer of zeste homolog 2 (EZH2) knockdown improved Cldn5 expression and alleviated depression-like behaviors by suppressing the tri-methylation of lysine 27 on histone 3 (H3K27me3) in chronically stressed mice. Furthermore, the stress-induced excessive transfer of peripheral cytokine tumor necrosis factor-α (TNF-α) into the hippocampus was prevented by Claudin-5 overexpression and EZH2 knockdown. Interestingly, antidepressant treatment could inhibit H3K27me3 deposition at the Cldn5 promoter, reversing the loss of the encoded protein and BBB damage. Considered together, these findings reveal the importance of the hippocampal EZH2-Claudin-5 axis in regulating neurovascular function and MDD development, providing potential therapeutic targets for this psychiatric illness.


Asunto(s)
Barrera Hematoencefálica , Trastorno Depresivo Mayor , Humanos , Masculino , Ratones , Animales , Barrera Hematoencefálica/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Histonas/metabolismo , Claudina-5/genética , Claudina-5/metabolismo , Depresión/metabolismo , Trastorno Depresivo Mayor/metabolismo , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Ratones Endogámicos C57BL
14.
EMBO Rep ; 23(2): e53543, 2022 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-34842321

RESUMEN

Single-cell RNA sequencing (scRNA-seq) is a powerful technique for dissecting the complexity of normal and diseased tissues, enabling characterization of cell diversity and heterogeneous phenotypic states in unprecedented detail. However, this technology has been underutilized for exploring the interactions between the host cell and viral pathogens in latently infected cells. Herein, we use scRNA-seq and single-molecule sensitivity fluorescent in situ hybridization (smFISH) technologies to investigate host single-cell transcriptome changes upon the reactivation of a human neurotropic virus, herpes simplex virus-1 (HSV-1). We identify the stress sensor growth arrest and DNA damage-inducible 45 beta (Gadd45b) as a critical antiviral host factor that regulates HSV-1 reactivation events in a subpopulation of latently infected primary neurons. We show that distinct subcellular localization of Gadd45b correlates with the viral late gene expression program, as well as the expression of the viral transcription factor, ICP4. We propose that a hallmark of a "successful" or "aborted" HSV-1 reactivation state in primary neurons is determined by a unique subcellular localization signature of the stress sensor Gadd45b.


Asunto(s)
Antígenos de Diferenciación/metabolismo , Herpesvirus Humano 1 , Neuronas/virología , Activación Viral , Latencia del Virus , Regulación de la Expresión Génica , Herpesvirus Humano 1/fisiología , Humanos , Hibridación Fluorescente in Situ , Transcriptoma
15.
Am J Geriatr Psychiatry ; 32(8): 922-939, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38290937

RESUMEN

OBJECTIVE: Obstructive sleep apnea (OSA) is associated with impaired cognitive function. Exosomes are secreted by most cells and play a role in OSA-associated cognitive impairment (CI). The aim of this study was to investigate whether OSA plasma-derived exosomes cause CI through hippocampal neuronal cell pyroptosis, and to identify exosomal miRNAs in OSA plasma-derived. MATERIALS AND METHODS: Plasma-derived exosomes were isolated from patients with severe OSA and healthy comparisons. Daytime sleepiness and cognitive function were assessed using the Epworth Sleepiness Scale (ESS) and the Beijing version of the Montreal Cognitive Assessment Scale (MoCA). Exosomes were coincubated with mouse hippocampal neurons (HT22) cells to evaluate the effect of exosomes on pyroptosis and inflammation of HT22 cells. Meanwhile, exosomes were injected into C57BL/6 male mice via caudal vein, and then morris water maze was used to evaluate the spatial learning and memory ability of the mice, so as to observe the effects of exosomes on the cognitive function of the mice. Western blot and qRT-PCR were used to detect the expressions of Gasdermin D (GSDMD) and Caspase-1 to evaluate the pyroptosis level. The expression of IL-1ß, IL-6, IL-18 and TNF-α was detected by qRT-PCR to assess the level of inflammation. Correlations of GSDMD and Caspase-1 expression with clinical parameters were evaluated using Spearman's rank correlation analysis. In addition, plasma exosome miRNAs profile was identified, followed by Gene Ontology (GO) term and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. RESULTS: Compared to healthy comparisons, body mass index (BMI), apnea-hypopnea index (AHI), oxygen desaturation index (ODI), and ESS scores were increased in patients with severe OSA, while lowest oxygen saturation during sleep (LSaO2), mean oxygen saturation during sleep (MSaO2) and MoCA scores were decreased. Compared to the PBS group (NC) and the healthy comparison plasma-derived exosomes (NC-EXOS), the levels of GSDMD and Caspase-1 and IL-1ß, IL-6, IL-18 and TNF-α were increased significantly in the severe OSA plasma-derived exosomes (OSA-EXOS) coincubated with HT22 cells. Compared to the NC and NC-EXOS groups, the learning and memory ability of mice injected with OSA-EXOS was decreased, and the expression of GSDMD and Caspase-1 in hippocampus were significantly increased, along with the levels of IL-1ß, IL-6, IL-18 and TNF-α. Spearman correlation analysis found that clinical AHI in HCs and severe OSA patients was positively correlated with GSDMD and Caspase-1 in HT22 cells from NC-EXOS and OSA-EXOS groups, while negatively correlated with clinical MoCA. At the same time, clinical MoCA in HCs and severe OSA patients was negatively correlated with GSDMD and Caspase-1 in HT22 cells from NC-EXOS and OSA-EXOS groups. A unique exosomal miRNAs profile was identified in OSA-EXOS group compared to the NC-EXOS group, in which 28 miRNAs were regulated and several KEGG and GO pathways were identified. CONCLUSIONS: The results of this study show a hypothesis that plasma-derived exosomes from severe OSA patients promote pyroptosis and increased expression of inflammatory factors in vivo and in vitro, and lead to impaired cognitive function in mice, suggesting that OSA-EXOS can mediate CI through pyroptosis of hippocampal neurons. In addition, exosome cargo from OSA-EXOS showed a unique miRNAs profile compared to NC-EXOS, suggesting that plasma exosome associated miRNAs may reflect the differential profile of OSA related diseases, such as CI.


Asunto(s)
Disfunción Cognitiva , Exosomas , Hipocampo , Ratones Endogámicos C57BL , MicroARNs , Neuronas , Piroptosis , Apnea Obstructiva del Sueño , Exosomas/metabolismo , Animales , Piroptosis/fisiología , Hipocampo/metabolismo , Masculino , Ratones , Humanos , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/etiología , Neuronas/metabolismo , Apnea Obstructiva del Sueño/metabolismo , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/fisiopatología , MicroARNs/metabolismo , MicroARNs/genética , MicroARNs/sangre , Proteínas de Unión a Fosfato/metabolismo , Persona de Mediana Edad , Femenino , Caspasa 1/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Estudios de Casos y Controles , Gasderminas
16.
Artículo en Inglés | MEDLINE | ID: mdl-38842766

RESUMEN

BACKGROUND: Group A streptococcal(GAS) meningitis is a severe disease with a high case fatality rate. In the era of increasing GAS meningitis, our understanding about this disease is limited. PURPOSE: To gain a better understanding about GAS meningitis. METHODS: Five new cases with GAS meningitis were reported. GAS meningitis related literatures were searched for systematic review in PUBMED and EMBASE. Case reports and case series on paediatric cases were included. Information on demographics, risk factors, symptoms, treatments, outcomes, and emm types of GAS was summarized. RESULTS: Totally 263 cases were included. Among 100 individuals, 9.9% (8/81) had prior varicella, 11.1% (9/81) had anatomical factors, and 53.2% (42/79) had extracranial infections. Soft tissue infections were common among infants (10/29, 34.5%), while ear/sinus infections were more prevalent in children ≥ 3 years (21/42, 50.0%). The overall case fatality rate (CFR) was 16.2% (12/74). High risk of death was found in patients with shock or systemic complications, young children(< 3 years) and cases related to hematogenic spread. The predominate cause of death was shock(6/8). Among the 163 patients included in case series studies, ear/sinus infections ranged from 21.4 to 62.5%, while STSS/shock ranged from 12.5 to 35.7%, and the CFR ranged from 5.9 to 42.9%. CONCLUSIONS: A history of varicella, soft tissue infections, parameningeal infections and CSF leaks are important clinical clues to GAS in children with meningitis. Young children and hematogenic spread related cases need to be closely monitored for shock due to the high risk of death.

17.
Phys Chem Chem Phys ; 26(24): 17182-17190, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38847738

RESUMEN

ZnSeTe quantum dots (QDs) attract growing interest owing to their low threats to health and the environment. They are widely applied as emitters in displays and lighting devices. Previous findings have indicated that inorganic halides are excellent candidates for surface ligands on QDs. By incorporating inorganic halides during the synthesis process, the photoluminescence (PL) intensity and quantum yield (QY) of QDs can be significantly enhanced. However, the alteration of surface states in QDs induced by zinc halide modification and the mechanism of formation of trap-state radiative recombination processes have been less discussed. Herein, we proposed a synthesis strategy for ZnSeTe/ZnSe/ZnSeS/ZnS core/shell/shell/shell QDs modified with ZnCl2, and by comparing the morphology and elemental composition of QDs with different amounts of ZnCl2 added, we revealed the regulatory mechanism of nanocrystal growth in the presence of ZnCl2. QDs with modification of ZnCl2 exhibited broad yellow fluorescence, distinct from the intrinsic blue emission. Through spectroscopic and surface ligand analyses, we attributed this yellow emission to the intermediate state energy levels caused by the defects on the surface. Finally, we used the QDs with broad linewidth emission to fabricate a simple white-light-emitting diode (WLED). This work provided new insights into the role of inorganic ligands and the use of a single emitting material in solid-state lighting devices.

18.
BMC Geriatr ; 24(1): 531, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898411

RESUMEN

BACKGROUND: Mild cognitive impairment has received widespread attention as a high-risk population for Alzheimer's disease, and many studies have developed or validated predictive models to assess it. However, the performance of the model development remains unknown. OBJECTIVE: The objective of this review was to provide an overview of prediction models for the risk of Alzheimer's disease dementia in older adults with mild cognitive impairment. METHOD: PubMed, EMBASE, Web of Science, and MEDLINE were systematically searched up to October 19, 2023. We included cohort studies in which risk prediction models for Alzheimer's disease dementia in older adults with mild cognitive impairment were developed or validated. The Predictive Model Risk of Bias Assessment Tool (PROBAST) was employed to assess model bias and applicability. Random-effects models combined model AUCs and calculated (approximate) 95% prediction intervals for estimations. Heterogeneity across studies was evaluated using the I2 statistic, and subgroup analyses were conducted to investigate sources of heterogeneity. Additionally, funnel plot analysis was utilized to identify publication bias. RESULTS: The analysis included 16 studies involving 9290 participants. Frequency analysis of predictors showed that 14 appeared at least twice and more, with age, functional activities questionnaire, and Mini-mental State Examination scores of cognitive functioning being the most common predictors. From the studies, only two models were externally validated. Eleven studies ultimately used machine learning, and four used traditional modelling methods. However, we found that in many of the studies, there were problems with insufficient sample sizes, missing important methodological information, lack of model presentation, and all of the models were rated as having a high or unclear risk of bias. The average AUC of the 15 best-developed predictive models was 0.87 (95% CI: 0.83, 0.90). DISCUSSION: Most published predictive modelling studies are deficient in rigour, resulting in a high risk of bias. Upcoming research should concentrate on enhancing methodological rigour and conducting external validation of models predicting Alzheimer's disease dementia. We also emphasize the importance of following the scientific method and transparent reporting to improve the accuracy, generalizability and reproducibility of study results. REGISTRATION: This systematic review was registered in PROSPERO (Registration ID: CRD42023468780).


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/epidemiología , Disfunción Cognitiva/psicología , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/psicología , Anciano , Medición de Riesgo/métodos
19.
BMC Public Health ; 24(1): 749, 2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38459461

RESUMEN

BACKGROUND: Racial/ethnic disparities in the HIV care continuum have been well documented in the US, with especially striking inequalities in viral suppression rates between White and Black persons with HIV (PWH). The South is considered an epicenter of the HIV epidemic in the US, with the largest population of PWH living in Florida. It is unclear whether any disparities in viral suppression or immune reconstitution-a clinical outcome highly correlated with overall prognosis-have changed over time or are homogenous geographically. In this analysis, we 1) investigate longitudinal trends in viral suppression and immune reconstitution among PWH in Florida, 2) examine the impact of socio-ecological factors on the association between race/ethnicity and clinical outcomes, 3) explore spatial and temporal variations in disparities in clinical outcomes. METHODS: Data were obtained from the Florida Department of Health for 42,369 PWH enrolled in the Ryan White program during 2008-2020. We linked the data to county-level socio-ecological variables available from County Health Rankings. GEE models were fit to assess the effect of race/ethnicity on immune reconstitution and viral suppression longitudinally. Poisson Bayesian hierarchical models were fit to analyze geographic variations in racial/ethnic disparities while adjusting for socio-ecological factors. RESULTS: Proportions of PWH who experienced viral suppression and immune reconstitution rose by 60% and 45%, respectively, from 2008-2020. Odds of immune reconstitution and viral suppression were significantly higher among White [odds ratio =2.34, 95% credible interval=2.14-2.56; 1.95 (1.85-2.05)], and Hispanic [1.70 (1.54-1.87); 2.18(2.07-2.31)] PWH, compared with Black PWH. These findings remained unchanged after accounting for socio-ecological factors. Rural and urban counties in north-central Florida saw the largest racial/ethnic disparities. CONCLUSIONS: There is persistent, spatially heterogeneous, racial/ethnic disparity in HIV clinical outcomes in Florida. This disparity could not be explained by socio-ecological factors, suggesting that further research on modifiable factors that can improve HIV outcomes among Black and Hispanic PWH in Florida is needed.


Asunto(s)
Etnicidad , Infecciones por VIH , Humanos , Teorema de Bayes , Florida/epidemiología , Disparidades en Atención de Salud , Hispánicos o Latinos , Infecciones por VIH/epidemiología , Blanco , Negro o Afroamericano
20.
Eur Spine J ; 33(3): 1098-1108, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38153529

RESUMEN

PURPOSE: This study aimed to establish a nomogram to predict the risk of venous thromboembolism (VTE), identifying potential risk factors, and providing theoretical basis for prevention of VTE after spinal surgery. METHODS: A retrospective analysis was conducted on 2754 patients who underwent spinal surgery. The general characteristics of the training group were initially screened using univariate logistic analysis, and the LASSO method was used for optimal prediction. Subsequently, multivariate logistic regression analysis was performed to identify independent risk factors for postoperative VTE in the training group, and a nomogram for predict risk of VTE was established. The discrimination, calibration, and clinical usefulness of the nomogram were separately evaluated using the C-index, receiver operating characteristic curve, calibration plot and clinical decision curve, and was validated using data from the validation group finally. RESULTS: Multivariate logistic regression analysis identified 10 independent risk factors for VTE after spinal surgery. A nomogram was established based on these independent risk factors. The C-index for the training and validation groups indicating high accuracy and stability of the model. The area under the receiver operating characteristic curve indicating excellent discrimination ability; the calibration curves showed outstanding calibration for both the training and validation groups. Decision curve analysis showed the clinical net benefit of using the nomogram could be maximized in the probability threshold range of 0.01-1. CONCLUSION: Patients undergoing spinal surgery with elevated D-dimer levels, prolonger surgical, and cervical surgery have higher risk of VTE. The nomogram can provide a theoretical basis for clinicians to prevent VTE.


Asunto(s)
Nomogramas , Tromboembolia Venosa , Humanos , Estudios Retrospectivos , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología , Tromboembolia Venosa/prevención & control , Procedimientos Neuroquirúrgicos , Cuello , Factores de Riesgo
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