Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.925
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Cell ; 187(11): 2717-2734.e33, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38653239

RESUMEN

The gut microbiota has been found to play an important role in the progression of metabolic dysfunction-associated steatohepatitis (MASH), but the mechanisms have not been established. Here, by developing a click-chemistry-based enrichment strategy, we identified several microbial-derived bile acids, including the previously uncharacterized 3-succinylated cholic acid (3-sucCA), which is negatively correlated with liver damage in patients with liver-tissue-biopsy-proven metabolic dysfunction-associated fatty liver disease (MAFLD). By screening human bacterial isolates, we identified Bacteroides uniformis strains as effective producers of 3-sucCA both in vitro and in vivo. By activity-based protein purification and identification, we identified an enzyme annotated as ß-lactamase in B. uniformis responsible for 3-sucCA biosynthesis. Furthermore, we found that 3-sucCA is a lumen-restricted metabolite and alleviates MASH by promoting the growth of Akkermansia muciniphila. Together, our data offer new insights into the gut microbiota-liver axis that may be leveraged to augment the management of MASH.


Asunto(s)
Akkermansia , Bacteroides , Ácidos y Sales Biliares , Microbioma Gastrointestinal , Enfermedad del Hígado Graso no Alcohólico , Simbiosis , Animales , Humanos , Masculino , Ratones , Akkermansia/metabolismo , Bacteroides/metabolismo , beta-Lactamasas/metabolismo , Ácidos y Sales Biliares/metabolismo , Vías Biosintéticas/genética , Hígado Graso/metabolismo , Hígado/metabolismo , Ratones Endogámicos C57BL , Verrucomicrobia/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/microbiología
2.
Cell ; 184(1): 207-225.e24, 2021 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-33333019

RESUMEN

Regulation of biological processes typically incorporates mechanisms that initiate and terminate the process and, where understood, these mechanisms often involve feedback control. Regulation of transcription is a fundamental cellular process where the mechanisms involved in initiation have been studied extensively, but those involved in arresting the process are poorly understood. Modeling of the potential roles of RNA in transcriptional control suggested a non-equilibrium feedback control mechanism where low levels of RNA promote condensates formed by electrostatic interactions whereas relatively high levels promote dissolution of these condensates. Evidence from in vitro and in vivo experiments support a model where RNAs produced during early steps in transcription initiation stimulate condensate formation, whereas the burst of RNAs produced during elongation stimulate condensate dissolution. We propose that transcriptional regulation incorporates a feedback mechanism whereby transcribed RNAs initially stimulate but then ultimately arrest the process.


Asunto(s)
Retroalimentación Fisiológica , ARN/genética , Transcripción Genética , Animales , Complejo Mediador/metabolismo , Ratones , Modelos Biológicos , Células Madre Embrionarias de Ratones/metabolismo , ARN/biosíntesis , Electricidad Estática
3.
Mol Cell ; 83(14): 2449-2463.e13, 2023 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-37402367

RESUMEN

Transcription factors (TFs) orchestrate the gene expression programs that define each cell's identity. The canonical TF accomplishes this with two domains, one that binds specific DNA sequences and the other that binds protein coactivators or corepressors. We find that at least half of TFs also bind RNA, doing so through a previously unrecognized domain with sequence and functional features analogous to the arginine-rich motif of the HIV transcriptional activator Tat. RNA binding contributes to TF function by promoting the dynamic association between DNA, RNA, and TF on chromatin. TF-RNA interactions are a conserved feature important for vertebrate development and disrupted in disease. We propose that the ability to bind DNA, RNA, and protein is a general property of many TFs and is fundamental to their gene regulatory function.


Asunto(s)
ARN , Factores de Transcripción , Factores de Transcripción/metabolismo , ARN/metabolismo , Sitios de Unión , Unión Proteica , ADN/genética
4.
Nature ; 629(8012): 579-585, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38750235

RESUMEN

Towards realizing the future quantum internet1,2, a pivotal milestone entails the transition from two-node proof-of-principle experiments conducted in laboratories to comprehensive multi-node set-ups on large scales. Here we report the creation of memory-memory entanglement in a multi-node quantum network over a metropolitan area. We use three independent memory nodes, each of which is equipped with an atomic ensemble quantum memory3 that has telecom conversion, together with a photonic server where detection of a single photon heralds the success of entanglement generation. The memory nodes are maximally separated apart for 12.5 kilometres. We actively stabilize the phase variance owing to fibre links and control lasers. We demonstrate concurrent entanglement generation between any two memory nodes. The memory lifetime is longer than the round-trip communication time. Our work provides a metropolitan-scale testbed for the evaluation and exploration of multi-node quantum network protocols and starts a stage of quantum internet research.

5.
Nature ; 610(7932): 562-568, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36261549

RESUMEN

Tobacco smoking is positively correlated with non-alcoholic fatty liver disease (NAFLD)1-5, but the underlying mechanism for this association is unclear. Here we report that nicotine accumulates in the intestine during tobacco smoking and activates intestinal AMPKα. We identify the gut bacterium Bacteroides xylanisolvens as an effective nicotine degrader. Colonization of B. xylanisolvens reduces intestinal nicotine concentrations in nicotine-exposed mice, and it improves nicotine-exacerbated NAFLD progression. Mechanistically, AMPKα promotes the phosphorylation of sphingomyelin phosphodiesterase 3 (SMPD3), stabilizing the latter and therefore increasing intestinal ceramide formation, which contributes to NAFLD progression to non-alcoholic steatohepatitis (NASH). Our results establish a role for intestinal nicotine accumulation in NAFLD progression and reveal an endogenous bacterium in the human intestine with the ability to metabolize nicotine. These findings suggest a possible route to reduce tobacco smoking-exacerbated NAFLD progression.


Asunto(s)
Bacterias , Intestinos , Nicotina , Enfermedad del Hígado Graso no Alcohólico , Fumar Tabaco , Animales , Humanos , Ratones , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Ceramidas/biosíntesis , Nicotina/efectos adversos , Nicotina/metabolismo , Enfermedad del Hígado Graso no Alcohólico/inducido químicamente , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/microbiología , Esfingomielina Fosfodiesterasa/metabolismo , Fumar Tabaco/efectos adversos , Fumar Tabaco/metabolismo , Intestinos/efectos de los fármacos , Intestinos/microbiología , Proteínas Quinasas Activadas por AMP/metabolismo , Progresión de la Enfermedad
6.
J Immunol ; 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39093026

RESUMEN

Mitochondrial DNA (mtDNA) is frequently released from mitochondria, activating cGAS-STING signaling and inducing type I IFNs (IFN-Is) in systemic lupus erythematosus (SLE). Meanwhile, whether and how the glycolytic pathway was involved in such IFN-I responses in human SLE remain unclear. In this study, we found that monocytes from SLE patients exerted robust IFN-I generation and elevated level of cytosolic mtDNA. Transfection of mtDNA into THP-1 macrophages was efficient in inducing IFN-I responses, together with the strong glycolytic pathway that promoted lactate production, mimicking the SLE phenotype. Blockade of lactate generation abrogated such IFN-I responses and, vice versa, exogenous lactate enhanced the IFN-I generation. Mechanistically, lactate promoted the lactylation of cGAS, which inhibited its binding to E3 ubiquitination ligase MARCHF5, blocking cGAS degradation and leading to strong IFN-I responses. In accordance, targeting lactate generation alleviated disease development in humanized SLE chimeras. Collectively, cytosolic mtDNA drives metabolic adaption toward the glycolytic pathway, promoting lactylation of cGAS for licensing IFN-I responses in human SLE and thereby assigning the glycolytic pathway as a promising therapeutic target for SLE.

7.
Nature ; 578(7794): 240-245, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32051600

RESUMEN

A quantum internet that connects remote quantum processors1,2 should enable a number of revolutionary applications such as distributed quantum computing. Its realization will rely on entanglement of remote quantum memories over long distances. Despite enormous progress3-12, at present the maximal physical separation achieved between two nodes is 1.3 kilometres10, and challenges for longer distances remain. Here we demonstrate entanglement of two atomic ensembles in one laboratory via photon transmission through city-scale optical fibres. The atomic ensembles function as quantum memories that store quantum states. We use cavity enhancement to efficiently create atom-photon entanglement13-15 and we use quantum frequency conversion16 to shift the atomic wavelength to telecommunications wavelengths. We realize entanglement over 22 kilometres of field-deployed fibres via two-photon interference17,18 and entanglement over 50 kilometres of coiled fibres via single-photon interference19. Our experiment could be extended to nodes physically separated by similar distances, which would thus form a functional segment of the atomic quantum network, paving the way towards establishing atomic entanglement over many nodes and over much longer distances.

8.
Hepatology ; 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39094016

RESUMEN

BACKGROUND AIMS: The EAT-Lancet Commission devised a globally sustainable dietary pattern to jointly promote human health and sustainability. However, the extent to which this diet supports metabolic dysfunction-associated steatotic liver disease (MASLD) has not yet been assessed. This study aimed to investigate the association between the EAT-Lancet diet and risk of MASLD and its severity. APPROACH RESULTS: This prospective multi-cohort study included 15,263 adults from the Tianjin Chronic Low-grade Systemic Inflammation and Health (TCLSIH) cohort, 1,137 adults from the Guangzhou Nutrition and Health Study (GNHS) cohort, and 175,078 adults from the UK Biobank. Additionally, 228 Chinese adults from the Prospective Epidemic Research Specifically of Non-alcoholic Steatohepatitis (PERSONS) with biopsy-proven MASLD were included. An EAT-Lancet diet index was created to reflect adherence to the EAT-Lancet reference diet. The TCLSIH cohort recorded 3,010 MASLD cases during 53,575 person-years of follow-up, the GNHS cohort documented 624 MASLD cases during 6,454 person-years of follow-up, and the UK Biobank 1,350 developed MASLD cases during 1,745,432 person-years of follow-up. In multivariable models, participants in the highest tertiles of the EAT-Lancet diet index had a lower risk of MASLD compared with those in the lowest tertiles (TCLSIH: HR=0.87, 95% CI: 0.78, 0.96; GNHS: HR=0.79, 95% CI: 0.64, 0.98; UK Biobank: HR=0.73, 95% CI: 0.63, 0.85). Moreover, liver controlled attenuation parameter decreased with increasing the diet index in individuals with biopsy-proven MASLD (ß=-5.895; 95% CI: -10.014, -1.775). CONCLUSIONS: Adherence to the EAT-Lancet reference diet was inversely associated with risk of MASLD as well as its severity.

9.
Circ Res ; 133(3): 237-251, 2023 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-37345556

RESUMEN

BACKGROUND: Progressive cardiac fibrosis leads to ventricular wall stiffness, cardiac dysfunction, and eventually heart failure, but the underlying mechanism remains unexplored. PDCD5 (programmed cell death 5) ubiquitously expresses in tissues, including the heart; however, the role of PDCD5 in cardiac fibrosis is largely unknown. Therefore, this study aims at exploring the possible role and underlying mechanisms of PDCD5 in the pathogenesis of cardiac fibrosis. METHODS AND RESULTS: PDCD5 levels were found to be elevated in the serum obtained from patients with cardiac fibrosis, in fibrotic mice heart tissues after myocardial infarction, and in cardiac fibroblasts stimulated by Ang II (angiotensin II)- or TGF-ß1 (transforming growth factor-ß1). Overexpression of PDCD5 in cardiac fibroblasts or treatment with PDCD5 protein reduced the expression of profibrogenic proteins in response to TGF-ß1 stimulation, while knockdown of PDCD5 increased fibrotic responses. It has been demonstrated that SMAD3, a protein that is also known as mothers against decapentaplegic homolog 3, directly upregulated PDCD5 during cardiac fibrosis. Subsequently, the increased PDCD5 promoted HDAC3 (histone deacetylase 3) ubiquitination, thus, inhibiting HDAC3 to reduce fibrotic responses. Fibroblast-specific knock-in of PDCD5 in mice ameliorated cardiac fibrosis after myocardial infarction and enhanced cardiac function, and these protective effects were eliminated by AAV9-mediated HDAC3 overexpression. CONCLUSIONS: The findings of this study demonstrated that PDCD5 is upregulated by SMAD3 during cardiac fibrosis, which subsequently ameliorated progressive fibrosis and cardiac dysfunction through HDAC3 inhibition. Thus, this study suggests that PDCD5 functions as a negative feedback factor on fibrotic signaling pathways and might serve as a potential therapeutic target to suppress the progression of fibrotic responses.


Asunto(s)
Infarto del Miocardio , Factor de Crecimiento Transformador beta1 , Ratones , Animales , Factor de Crecimiento Transformador beta1/metabolismo , Infarto del Miocardio/metabolismo , Corazón , Fibroblastos/metabolismo , Apoptosis , Fibrosis , Proteína smad3/metabolismo , Miocardio/metabolismo
10.
EMBO Rep ; 24(2): e54006, 2023 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-36416244

RESUMEN

While previous studies have identified cancer stem-like cells (CSCs) as a crucial driver for chemoresistance and tumor recurrence, the underlying mechanisms for populating the CSC pool remain unclear. Here, we identify hypermitophagy as a feature of human lung CSCs, promoting metabolic adaption via the Notch1-AMPK axis to drive CSC expansion. Specifically, mitophagy is highly active in CSCs, resulting in increased mitochondrial DNA (mtDNA) content in the lysosome. Lysosomal mtDNA acts as an endogenous ligand for Toll-like receptor 9 (TLR9) that promotes Notch1 activity. Notch1 interacts with AMPK to drive lysosomal AMPK activation by inducing metabolic stress and LKB1 phosphorylation. This TLR9-Notch1-AMPK axis supports mitochondrial metabolism to fuel CSC expansion. In patient-derived xenograft chimeras, targeting mitophagy and TLR9-dependent Notch1-AMPK pathway restricts tumor growth and CSC expansion. Taken together, mitochondrial hemostasis is interlinked with innate immune sensing and Notch1-AMPK activity to increase the CSC pool of human lung cancer.


Asunto(s)
Neoplasias Pulmonares , Receptor Toll-Like 9 , Humanos , Receptor Toll-Like 9/metabolismo , Mitofagia , Proteínas Quinasas Activadas por AMP/metabolismo , Pulmón , Neoplasias Pulmonares/patología , ADN Mitocondrial/genética , Células Madre Neoplásicas/metabolismo , Línea Celular Tumoral
11.
Gut ; 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39089860

RESUMEN

BACKGROUND: Statins have multiple benefits in patients with metabolic-associated steatotic liver disease (MASLD). AIM: To explore the effects of statins on the long-term risk of all-cause mortality, liver-related clinical events (LREs) and liver stiffness progression in patients with MASLD. METHODS: This cohort study collected data on patients with MASLD undergoing at least two vibration-controlled transient elastography examinations at 16 tertiary referral centres. Cox regression analysis was performed to examine the association between statin usage and long-term risk of all-cause mortality and LREs stratified by compensated advanced chronic liver disease (cACLD): baseline liver stiffness measurement (LSM) of ≥10 kPa. Liver stiffness progression was defined as an LSM increase of ≥20% for cACLD and from <10 kPa to ≥10 or LSM for non-cACLD. Liver stiffness regression was defined as LSM reduction from ≥10 kPa to <10 or LSM decrease of ≥20% for cACLD. RESULTS: We followed up 7988 patients with baseline LSM 5.9 kPa (IQR 4.6-8.2) for a median of 4.6 years. At baseline, 40.5% of patients used statins, and cACLD was present in 17%. Statin usage was significantly associated with a lower risk of all-cause mortality (adjusted HR=0.233; 95% CI 0.127 to 0.426) and LREs (adjusted HR=0.380; 95% CI 0.268 to 0.539). Statin usage was also associated with lower liver stiffness progression rates in cACLD (HR=0.542; 95% CI 0.389 to 0.755) and non-cACLD (adjusted HR=0.450; 95% CI 0.342 to 0.592), but not with liver stiffness regression (adjusted HR=0.914; 95% CI 0.778 to 1.074). CONCLUSIONS: Statin usage was associated with a relatively lower long-term risk of all-cause mortality, LREs and liver stiffness progression in patients with MASLD.

12.
J Hepatol ; 80(3): 419-430, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37984709

RESUMEN

BACKGROUND & AIMS: Patients with fatty liver disease may experience stigma from the disease or comorbidities. In this cross-sectional study, we aimed to understand stigma among patients with nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH) and healthcare providers. METHODS: Members of the Global NASH Council created two surveys about experiences/attitudes toward NAFLD and related diagnostic terms: a 68-item patient and a 41-item provider survey. RESULTS: Surveys were completed by 1,976 patients with NAFLD across 23 countries (51% Middle East/North Africa [MENA], 19% Europe, 17% USA, 8% Southeast Asia, 5% South Asia) and 825 healthcare providers (67% gastroenterologists/hepatologists) across 25 countries (39% MENA, 28% Southeast Asia, 22% USA, 6% South Asia, 3% Europe). Of all patients, 48% ever disclosed having NAFLD/NASH to family/friends; the most commonly used term was "fatty liver" (88% at least sometimes); "metabolic disease" or "MAFLD" were rarely used (never by >84%). Regarding various perceptions of diagnostic terms by patients, there were no substantial differences between "NAFLD", "fatty liver disease (FLD)", "NASH", or "MAFLD". The most popular response was being neither comfortable nor uncomfortable with either term (56%-71%), with slightly greater discomfort with "FLD" among the US and South Asian patients (47-52% uncomfortable). Although 26% of patients reported stigma related to overweight/obesity, only 8% reported a history of stigmatization or discrimination due to NAFLD. Among providers, 38% believed that the term "fatty" was stigmatizing, while 34% believed that "nonalcoholic" was stigmatizing, more commonly in MENA (43%); 42% providers (gastroenterologists/hepatologists 45% vs. 37% other specialties, p = 0.03) believed that the name change to metabolic dysfunction-associated steatotic liver disease (or MASLD) might reduce stigma. Regarding the new nomenclature, the percentage of providers reporting "steatotic liver disease" as stigmatizing was low (14%). CONCLUSIONS: The perception of NAFLD stigma varies among patients, providers, geographic locations and sub-specialties. IMPACT AND IMPLICATIONS: Over the past decades, efforts have been made to change the nomenclature of nonalcoholic fatty liver disease (NAFLD) to better align with its underlying pathogenetic pathways and remove any potential stigma associated with the name. Given the paucity of data related to stigma in NAFLD, we undertook this global comprehensive survey to assess stigma in NAFLD among patients and providers from around the world. We found there is a disconnect between physicians and patients related to stigma and related nomenclature. With this knowledge, educational programs can be developed to better target stigma in NAFLD among all stakeholders and to provide a better opportunity for the new nomenclature to address the issues of stigma.


Asunto(s)
Gastroenterólogos , Enfermedades Metabólicas , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Estudios Transversales , Comorbilidad , Obesidad/metabolismo , Enfermedades Metabólicas/complicaciones
13.
BMC Med ; 22(1): 278, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956533

RESUMEN

BACKGROUND: APRI and FIB-4 scores are used to exclude clinically significant fibrosis (defined as stage ≥ F2) in patients with chronic viral hepatitis. However, the cut-offs for these scores (generated by Youden indices) vary between different patient cohorts. This study aimed to evaluate whether serum dithiothreitol-oxidizing capacity (DOC), i.e., a surrogate test of quiescin sulfhydryl oxidase-1, which is a matrix remodeling enzyme, could be used to non-invasively identify significant fibrosis in patients with various chronic liver diseases (CLDs). METHODS: Diagnostic performance of DOC was compared with APRI and FIB-4 for identifying significant fibrosis. ROC curve analyses were undertaken in: a) two chronic hepatitis B (CHB) cohorts, independently established from hospitals in Wenzhou (n = 208) and Hefei (n = 120); b) a MASLD cohort from Wenzhou hospital (n = 122); and c) a cohort with multiple CLD etiologies (except CHB and MASLD; n = 102), which was identified from patients in both hospitals. Cut-offs were calculated using the Youden index. All CLD patients (n = 552) were then stratified by age for ROC curve analyses and cut-off calculations. RESULTS: Stratified by CLD etiology or age, ROC curve analyses consistently showed that the DOC test was superior to APRI and FIB-4 for discriminating between clinically significant fibrosis and no fibrosis, when APRI and FIB-4 showed poor/modest diagnostic performance (P < 0.05, P < 0.01 and P < 0.001 in 3, 1 and 3 cohort comparisons, respectively). Conversely, the DOC test was equivalent to APRI and FIB-4 when all tests showed moderate/adequate diagnostic performances (P > 0.05 in 11 cohort comparisons). DOC had a significant advantage over APRI or FIB-4 scores for establishing a uniform cut-off independently of age and CLD etiology (coefficients of variation of DOC, APRI and FIB-4 cut-offs were 1.7%, 22.9% and 47.6% in cohorts stratified by CLD etiology, 2.0%, 26.7% and 29.5% in cohorts stratified by age, respectively). The uniform cut-off was 2.13, yielded from all patients examined. Surprisingly, the uniform cut-off was the same as the DOC upper limit of normal with a specificity of 99%, estimated from 275 healthy control individuals. Hence, the uniform cut-off should possess a high negative predictive value for excluding significant fibrosis in primary care settings. A high DOC cut-off with 97.5% specificity could be used for detecting significant fibrosis (≥ F2) with an acceptable positive predictive value (87.1%). CONCLUSIONS: This proof-of-concept study suggests that the DOC test may efficiently rule out and rule in significant liver fibrosis, thereby reducing the numbers of unnecessary liver biopsies. Moreover, the DOC test may be helpful for clinicians to exclude significant liver fibrosis in the general population.


Asunto(s)
Biomarcadores , Ditiotreitol , Cirrosis Hepática , Humanos , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/sangre , Masculino , Persona de Mediana Edad , Biomarcadores/sangre , Femenino , Adulto , Anciano , Oxidación-Reducción , Curva ROC , Estudios de Cohortes , Oxidorreductasas actuantes sobre Donantes de Grupos Sulfuro/sangre , Prueba de Estudio Conceptual
14.
Small ; 20(3): e2303192, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37712177

RESUMEN

Modulating the electronic configuration of the substrate to achieve the optimal chemisorption toward polysulfides (LiPSs) for boosting polysulfide conversion is a promising way to the efficient Li-S batteries but filled with challenges. Herein, a Co/CoS2 heterostructure is elaborately built to tuning d-orbital electronic structure of CoS2 for a high-performance electrocatalyst. Theoretical simulations first evidence that Co metal as the electron donator can form a built-in electric field with CoS2 and downshift the d-band center, leading to the well-optimized adsorption strength for lithium polysulfides on CoS2 , thus contributing a favorable way for expediting the redox reaction kinetics of LiPSs. As verification of prediction, a Co/CoS2 heterostructure implanted in porous hollow N, S co-doped carbon nanocage (Co/CoS2 @NSC) is designed to realize the electronic configuration regulation and promote the electrochemical performance. Consequently, the batteries assembled with Co/CoS2 @NSC cathode display an outstanding specific capacity and an admirable cycling property as well as a salient property of 8.25 mAh cm-2 under 8.18 mg cm-2 . The DFT calculation also reveals the synergistic effect of N, S co-doping for enhancing polysulfide adsorption as well as the detriment of excessive sulfur doping.

15.
Hepatology ; 78(1): 195-211, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-36924031

RESUMEN

BACKGROUND AND AIMS: We evaluated the diagnostic accuracy of simple, noninvasive tests (NITs) in NAFLD patients with type 2 diabetes (T2D). METHODS AND RESULTS: This was an individual patient data meta-analysis of 1780 patients with biopsy-proven NAFLD and T2D. The index tests of interest were FIB-4, NAFLD Fibrosis Score (NFS), aspartate aminotransferase-to-platelet ratio index, liver stiffness measurement (LSM) by vibration-controlled transient elastography, and AGILE 3+. The target conditions were advanced fibrosis, NASH, and fibrotic NASH(NASH plus F2-F4 fibrosis). The diagnostic performance of noninvasive tests. individually or in sequential combination, was assessed by area under the receiver operating characteristic curve and by decision curve analysis. Comparison with 2278 NAFLD patients without T2D was also made. In NAFLD with T2D LSM and AGILE 3+ outperformed, both NFS and FIB-4 for advanced fibrosis (area under the receiver operating characteristic curve:LSM 0.82, AGILE 3+ 0.82, NFS 0.72, FIB-4 0.75, aspartate aminotransferase-to-platelet ratio index 0.68; p < 0.001 of LSM-based versus simple serum tests), with an uncertainty area of 12%-20%. The combination of serum-based with LSM-based tests for advanced fibrosis led to a reduction of 40%-60% in necessary LSM tests. Decision curve analysis showed that all scores had a modest net benefit for ruling out advanced fibrosis at the risk threshold of 5%-10% of missing advanced fibrosis. LSM and AGILE 3+ outperformed both NFS and FIB-4 for fibrotic NASH (area under the receiver operating characteristic curve:LSM 0.79, AGILE 3+ 0.77, NFS 0.71, FIB-4 0.71; p < 0.001 of LSM-based versus simple serum tests). All noninvasive scores were suboptimal for diagnosing NASH. CONCLUSIONS: LSM and AGILE 3+ individually or in low availability settings in sequential combination after FIB-4 or NFS have a similar good diagnostic accuracy for advanced fibrosis and an acceptable diagnostic accuracy for fibrotic NASH in NAFLD patients with T2D.


Asunto(s)
Diabetes Mellitus Tipo 2 , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Diabetes Mellitus Tipo 2/complicaciones , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/etiología , Índice de Severidad de la Enfermedad , Hígado/diagnóstico por imagen , Hígado/patología , Fibrosis , Gravedad del Paciente , Curva ROC , Biopsia , Aspartato Aminotransferasas
16.
Plant Physiol ; 192(4): 2768-2784, 2023 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-37096684

RESUMEN

In flowering plants, hundreds of RNA editing events occur in the chloroplasts and mitochondria during posttranscriptional processes. Although several pentatricopeptide repeat (PPR) proteins have been shown to form the editosome core, the precise interactions between the different editing factors are still obscure. Here, we isolated an Arabidopsis (Arabidopsis thaliana) PPR protein, designated DELAYED GREENING 409 (DG409), that was dually targeted to chloroplasts and mitochondria. This protein consists of 409 amino acids with 7 PPR motifs but lacks a C-terminal E, E+, or DYW domain. A mild dg409 knockdown mutant displays a sickly phenotype. In this mutant, the young leaves are pale green and turn green at maturity, and the development of chloroplasts and mitochondria is severely disrupted. Complete loss of DG409 function results in defective embryos. Transcriptomic analysis of the dg409 knockdown plants showed some editing defects in genes from both organelles, including CASEINOLYTIC PROTEASE P (clpP)-559, RNA POLYMERASE SUBUNIT ALPHA (rpoA)-200, ACETYL-COA CARBOXYLASE CARBOXYL TRANSFERASE SUBUNIT BETA (accD)-1568, NADH DEHYDROGENASE SUBUNIT 7 (nad7)-1505, and RIBOSOMAL PROTEIN S3 (rps3)-1344. RNA immunoprecipitation showed that DG409 was associated with the targeted transcripts in vivo. Interaction assays revealed that DG409 directly interacted with 2 DYW-type PPR proteins (EARLY CHLOROPLAST BIOGENESIS2 [AtECB2] and DYW DOMAIN PROTEIN2 [DYW2]) and 3 multiple organellar RNA editing factors (MORF2, MORF8, and MORF9). These results indicate that DG409 is involved in RNA editing via protein complexes and is therefore essential for chloroplast and mitochondrial development.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo
17.
Phys Rev Lett ; 132(23): 235001, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38905668

RESUMEN

Relativistic positron sources with high spin polarization have important applications in nuclear and particle physics and many frontier fields. However, it is challenging to produce dense polarized positrons. Here we present a simple and effective method to achieve such a positron source by directly impinging a relativistic high-density electron beam on the surface of a solid target. During the interaction, a strong return current of plasma electrons is induced and subsequently asymmetric quasistatic magnetic fields as high as megatesla are generated along the target surface. This gives rise to strong radiative spin flips and multiphoton processes, thus leading to efficient generation of copious polarized positrons. With three-dimensional particle-in-cell simulations, we demonstrate the production of a dense highly polarized multi-GeV positron beam with an average spin polarization above 40% and nC-scale charge per shot. This offers a novel route for the studies of laserless strong-field quantum electrodynamics physics and for the development of high-energy polarized positron sources.

18.
Chemistry ; 30(15): e202303586, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38079233

RESUMEN

Liquid crystalline nanoparticles (LC NPs) are a kind of polymer NPs with LC mesogens, which can form special anisotropic morphologies due to the influence of LC ordering. Owing to the stimuli-responsiveness of the LC blocks, LC NPs show abundant morphology evolution behaviors in response to external regulation. LC NPs have great application potential in nano-devices, drug delivery, special fibers and other fields. Polymerization-induced self-assembly (PISA) method can synthesize LC NPs at high solid content, reducing the harsh demand for reaction solvent of the LC polymers, being a better choice for large-scale production. In this review, we introduced recent research progress of PISA-LC NPs by dividing them into several parts according to the LC mesogen, and discussed the improvement of experimental conditions and the potential application of these polymers.

19.
Liver Int ; 44(7): 1526-1536, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38578141

RESUMEN

The rising prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) poses a significant global health challenge, affecting over 30% of adults worldwide. MASLD is linked to increased mortality rates and substantial healthcare costs, primarily driven by its progression to metabolic dysfunction-associated steatohepatitis (MASH), which can lead to severe liver complications including cirrhosis and hepatocellular carcinoma. Despite its growing burden, effective pharmacotherapy for MASLD/MASH has been lacking until the recent conditional approval of resmetirom by the FDA. Resmetirom, a liver-targeted thyroid hormone receptor-ß selective drug, has shown promise in clinical trials for treating non-cirrhotic MASH with moderate to advanced fibrosis. It has demonstrated efficacy in reducing hepatic fat content, improving liver histology (both MASH resolution and fibrosis improvement), and ameliorating biomarkers of liver damage without significant effects on body weight or glucose metabolism. Notably, resmetirom also exhibits favourable effects on circulating lipids, potentially reducing cardiovascular risk in MASLD/MASH patients. The safety profile of resmetirom appears acceptable, with gastrointestinal adverse events being the most common, though generally mild or moderate. However, long-term surveillance is warranted to monitor for potential risks related to thyroid, gonadal, or bone diseases. Clinical implementation of resmetirom faces challenges in patient selection and monitoring treatment response, and will heavily rely on non-invasive tests for liver fibrosis assessment. Nonetheless, resmetirom represents a landmark breakthrough in MASLD/MASH treatment, paving the way for future therapeutic strategies aiming to mitigate the multifaceted risks associated with this complex metabolic liver disease.


Asunto(s)
Hígado Graso , Humanos , Hígado Graso/tratamiento farmacológico , Receptores beta de Hormona Tiroidea/metabolismo , Cirrosis Hepática/tratamiento farmacológico , Hígado/patología , Hígado/efectos de los fármacos , Hígado/metabolismo , Piridazinas , Uracilo/análogos & derivados
20.
Liver Int ; 44(2): 330-343, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38014574

RESUMEN

Metabolic dysfunction-associated fatty liver disease (MAFLD) has reached epidemic proportions worldwide and is the most frequent cause of chronic liver disease in developed countries. Within the spectrum of liver disease in MAFLD, steatohepatitis is a progressive form of liver disease and hepatocyte ballooning (HB) is a cardinal pathological feature of steatohepatitis. The accurate and reproducible diagnosis of HB is therefore critical for the early detection and treatment of steatohepatitis. Currently, a diagnosis of HB relies on pathological examination by expert pathologists, which may be a time-consuming and subjective process. Hence, there has been interest in developing automated methods for diagnosing HB. This narrative review briefly discusses the development of artificial intelligence (AI) technology for diagnosing fatty liver disease pathology over the last 30 years and provides an overview of the current research status of AI algorithms for the identification of HB, including published articles on traditional machine learning algorithms and deep learning algorithms. This narrative review also provides a summary of object detection algorithms, including the principles, historical developments, and applications in the medical image analysis. The potential benefits of object detection algorithms for HB diagnosis (specifically those combined with a transformer architecture) are discussed, along with the future directions of object detection algorithms in HB diagnosis and the potential applications of generative AI on transformer architecture in this field. In conclusion, object detection algorithms have huge potential for the identification of HB and could make the diagnosis of MAFLD more accurate and efficient in the near future.


Asunto(s)
Inteligencia Artificial , Enfermedad del Hígado Graso no Alcohólico , Humanos , Algoritmos , Tecnología , Hepatocitos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA