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1.
Cell ; 160(6): 1246-60, 2015 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-25748654

RESUMEN

Genetic screens are powerful tools for identifying genes responsible for diverse phenotypes. Here we describe a genome-wide CRISPR/Cas9-mediated loss-of-function screen in tumor growth and metastasis. We mutagenized a non-metastatic mouse cancer cell line using a genome-scale library with 67,405 single-guide RNAs (sgRNAs). The mutant cell pool rapidly generates metastases when transplanted into immunocompromised mice. Enriched sgRNAs in lung metastases and late-stage primary tumors were found to target a small set of genes, suggesting that specific loss-of-function mutations drive tumor growth and metastasis. Individual sgRNAs and a small pool of 624 sgRNAs targeting the top-scoring genes from the primary screen dramatically accelerate metastasis. In all of these experiments, the effect of mutations on primary tumor growth positively correlates with the development of metastases. Our study demonstrates Cas9-based screening as a robust method to systematically assay gene phenotypes in cancer evolution in vivo.


Asunto(s)
Sistemas CRISPR-Cas , Carcinoma de Pulmón de Células no Pequeñas/genética , Técnicas de Inactivación de Genes , Neoplasias Pulmonares/genética , Metástasis de la Neoplasia/genética , Animales , Carcinoma de Pulmón de Células no Pequeñas/patología , Estudio de Asociación del Genoma Completo , Humanos , Neoplasias Pulmonares/patología , Ratones , ARN Guía de Kinetoplastida
2.
Cell ; 158(2): 449-461, 2014 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-25036638

RESUMEN

Reprogramming of somatic cells to induced pluripotent stem cells (iPSCs) holds enormous promise for regenerative medicine. To elucidate endogenous barriers limiting this process, we systematically dissected human cellular reprogramming by combining a genome-wide RNAi screen, innovative computational methods, extensive single-hit validation, and mechanistic investigation of relevant pathways and networks. We identify reprogramming barriers, including genes involved in transcription, chromatin regulation, ubiquitination, dephosphorylation, vesicular transport, and cell adhesion. Specific a disintegrin and metalloproteinase (ADAM) proteins inhibit reprogramming, and the disintegrin domain of ADAM29 is necessary and sufficient for this function. Clathrin-mediated endocytosis can be targeted with small molecules and opposes reprogramming by positively regulating TGF-ß signaling. Genetic interaction studies of endocytosis or ubiquitination reveal that barrier pathways can act in linear, parallel, or feedforward loop architectures to antagonize reprogramming. These results provide a global view of barriers to human cellular reprogramming.


Asunto(s)
Reprogramación Celular , Células Madre Pluripotentes Inducidas/citología , Proteínas ADAM/metabolismo , Adhesión Celular , Células Madre Embrionarias/metabolismo , Endocitosis , Humanos , Ubiquitina/metabolismo
3.
Nature ; 589(7842): 462-467, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33328628

RESUMEN

Mechanical deformations of DNA such as bending are ubiquitous and have been implicated in diverse cellular functions1. However, the lack of high-throughput tools to measure the mechanical properties of DNA has limited our understanding of how DNA mechanics influence chromatin transactions across the genome. Here we develop 'loop-seq'-a high-throughput assay to measure the propensity for DNA looping-and determine the intrinsic cyclizabilities of 270,806 50-base-pair DNA fragments that span Saccharomyces cerevisiae chromosome V, other genomic regions, and random sequences. We found sequence-encoded regions of unusually low bendability within nucleosome-depleted regions upstream of transcription start sites (TSSs). Low bendability of linker DNA inhibits nucleosome sliding into the linker by the chromatin remodeller INO80, which explains how INO80 can define nucleosome-depleted regions in the absence of other factors2. Chromosome-wide, nucleosomes were characterized by high DNA bendability near dyads and low bendability near linkers. This contrast increases for deeper gene-body nucleosomes but disappears after random substitution of synonymous codons, which suggests that the evolution of codon choice has been influenced by DNA mechanics around gene-body nucleosomes. Furthermore, we show that local DNA mechanics affect transcription through TSS-proximal nucleosomes. Overall, this genome-scale map of DNA mechanics indicates a 'mechanical code' with broad functional implications.


Asunto(s)
Fenómenos Biomecánicos , ADN de Hongos/química , ADN de Hongos/genética , Genoma Fúngico , Saccharomyces cerevisiae/genética , Ensamble y Desensamble de Cromatina , Codón/genética , ADN de Hongos/metabolismo , Nucleosomas/química , Nucleosomas/genética , Nucleosomas/metabolismo , Docilidad , Proteínas de Saccharomyces cerevisiae/metabolismo , Sitio de Iniciación de la Transcripción
4.
J Cell Sci ; 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39355864

RESUMEN

PROMININ-1 (PROM1) mutations are associated with inherited, non-syndromic vision loss. We used CRISPR/Cas9 to induce prom1-null mutations in Xenopus laevis and then tracked retinal disease progression from the ages of 6 weeks to 3 years old. Prom1-null associated retinal degeneration in frogs is age-dependent and involves RPE dysfunction preceding photoreceptor degeneration. Before photoreceptor degeneration occurs, aging prom1-null frogs develop increasing size and numbers of cellular debris deposits in the subretinal space and outer segment layer, which resemble subretinal drusenoid deposits (SDD) in their location, histology, and representation in color fundus photography and optical coherence tomography (OCT). Evidence for an RPE origin of these deposits includes infiltration of pigment granules into the deposits, thinning of RPE as measured by OCT, and RPE disorganization as measured by histology and OCT. The appearance and accumulation of SDD-like deposits and RPE thinning and disorganization in our animal model suggests an underlying disease mechanism for prom1-null mediated blindness of death and dysfunction of the RPE preceding photoreceptor degeneration, instead of direct effects upon photoreceptor outer segment morphogenesis, as was previously hypothesized.

5.
Chem Rev ; 124(13): 8307-8472, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38924776

RESUMEN

Due to the intrinsic non-invasive nature, cost-effectiveness, high safety, and real-time capabilities, besides diagnostic imaging, ultrasound as a typical mechanical wave has been extensively developed as a physical tool for versatile biomedical applications. Especially, the prosperity of nanotechnology and nanomedicine invigorates the landscape of ultrasound-based medicine. The unprecedented surge in research enthusiasm and dedicated efforts have led to a mass of multifunctional micro-/nanosystems being applied in ultrasound biomedicine, facilitating precise diagnosis, effective treatment, and personalized theranostics. The effective deployment of versatile ultrasound-based micro-/nanosystems in biomedical applications is rooted in a profound understanding of the relationship among composition, structure, property, bioactivity, application, and performance. In this comprehensive review, we elaborate on the general principles regarding the design, synthesis, functionalization, and optimization of ultrasound-based micro-/nanosystems for abundant biomedical applications. In particular, recent advancements in ultrasound-based micro-/nanosystems for diagnostic imaging are meticulously summarized. Furthermore, we systematically elucidate state-of-the-art studies concerning recent progress in ultrasound-based micro-/nanosystems for therapeutic applications targeting various pathological abnormalities including cancer, bacterial infection, brain diseases, cardiovascular diseases, and metabolic diseases. Finally, we conclude and provide an outlook on this research field with an in-depth discussion of the challenges faced and future developments for further extensive clinical translation and application.


Asunto(s)
Neoplasias , Humanos , Animales , Neoplasias/diagnóstico por imagen , Neoplasias/terapia , Ultrasonografía/métodos , Nanomedicina/métodos , Nanotecnología/métodos
6.
Proc Natl Acad Sci U S A ; 120(13): e2213480120, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-36952380

RESUMEN

Peroxidase-like catalysts are safe and low-cost candidates to tackle the dilemma in constructing sustainable cathodic heterogeneous electro-Fenton (CHEF) catalysts for water purification, but the elusive structure-property relationship of enzyme-like catalysts constitutes a pressing challenge for the advancement of CHEF processes in practically relevant water and wastewater treatment. Herein, we probe the origins of catalytic efficiency in the CHEF process by artificially tailoring the peroxidase-like activity of Fe3O4 through a series of acetylated chitosan-based hydrogels, which serve as ecofriendly alternatives to traditional carbon shells. The optimized acetylated chitosan wrapping Fe3O4 hydrogel on the cathode shows an impressive activity and stability in CHEF process, overcoming the complicated and environmentally unfavored procedures in the electro-Fenton-related processes. Structural characterizations and theoretical calculations reveal that the amide group in chitosan can modulate the intrinsic redox capacity of surficial Fe sites on Fe3O4 toward CHEF catalysis via the neutral hydrogen bond. This work provides a sustainable path and molecule-level insight for the rational design of high-efficiency CHEF catalysts and beyond.

7.
Nat Mater ; 23(8): 1093-1099, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38702413

RESUMEN

Electrochemomechanical degradation is one of the most common causes of capacity deterioration in high-energy-density cathodes, particularly intercalation-based layered oxides. Here we reveal the presence of rotational stacking faults (RSFs) in layered lithium transition-metal oxides, arising from specific stacking sequences at different angles, and demonstrate their critical role in determining structural/electrochemical stability. Our combined experiments and calculations show that RSFs facilitate oxygen dimerization and transition-metal migration in layered oxides, fostering microcrack nucleation/propagation concurrently with cumulative electrochemomechanical degradation on cycling. We further show that thermal defect annihilation as a potential solution can suppress RSFs, reducing microcracks and enhancing cyclability in lithium-rich layered cathodes. The common but previously overlooked occurrence of RSFs suggests a new synthesis guideline of high-energy-density layered oxide cathodes.

8.
Cell ; 141(6): 994-1005, 2010 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-20550935

RESUMEN

DICER is a central regulator of microRNA maturation. However, little is known about mechanisms regulating its expression in development or disease. While profiling miRNA expression in differentiating melanocytes, two populations were observed: some upregulated at the pre-miRNA stage, and others upregulated as mature miRNAs (with stable pre-miRNA levels). Conversion of pre-miRNAs to fully processed miRNAs appeared to be dependent upon stimulation of DICER expression--an event found to occur via direct transcriptional targeting of DICER by the melanocyte master transcriptional regulator MITF. MITF binds and activates a conserved regulatory element upstream of DICER's transcriptional start site upon melanocyte differentiation. Targeted KO of DICER is lethal to melanocytes, at least partly via DICER-dependent processing of the pre-miRNA-17 approximately 92 cluster thus targeting BIM, a known proapoptotic regulator of melanocyte survival. These observations highlight a central mechanism underlying lineage-specific miRNA regulation which could exist for other cell types during development.


Asunto(s)
Regulación de la Expresión Génica , Melanocitos/metabolismo , Factor de Transcripción Asociado a Microftalmía/metabolismo , Ribonucleasa III/metabolismo , Transcripción Genética , Animales , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteína 11 Similar a Bcl2 , Diferenciación Celular , Supervivencia Celular , Células Cultivadas , Células Epidérmicas , Técnicas de Silenciamiento del Gen , Folículo Piloso/metabolismo , Humanos , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , MicroARNs/metabolismo , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas/metabolismo , Regulación hacia Arriba
9.
Exp Cell Res ; : 114314, 2024 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-39481795

RESUMEN

Melatonin (MLT) has been shown to induce polarization of macrophages towards M2-like phenotype and inhibit polarization of macrophages towards M1-like phenotype through exogenous administration, which affects the development of many macrophage polarization-related diseases, such as infectious diseases, cardiovascular diseases, bone diseases, and tumors. However, whether endogenous melatonin has similar influences on macrophage polarization as exogenous melatonin is still under investigation. This study revealed that the process of lipopolysaccharide (LPS) inducing macrophages to polarize towards M1-like phenotype was accompanied by an increase in endogenous MLT secretion. To explore the role of increased endogenous MLT in the polarization process of macrophages, whether similar to the function of exogenous MLT in inhibiting polarization of macrophages towards M1-like phenotype, we established LPS-induced MLT deficiency models in vitro to investigate the effects of endogenous MLT on the secretion of cytokines, co-stimulatory molecules, ROS, and phagocytic function in LPS-induced M1-like macrophages. Additionally, we aimed to elucidate the mechanism by which LPS affects the secretion of endogenous MLT by macrophages. Our results confirm that LPS induces transcription of Aanat through the TLR4/TRIF pathway, consequently facilitating the secretion of MLT by macrophages. In this way, IRF3 is the main transcription factor that regulates Aanat transcription. Endogenous MLT plays a role in inhibiting the polarization of macrophages towards M1 phenotype and delaying cell apoptosis during LPS-induced polarization towards M1 phenotype. This phenomenon may be a form of self-protection that occurs when macrophages engulf pathogens while avoiding oxidative stress and apoptosis caused by LPS. This conclusion clarifies the role of endogenous MLT in the clearance of pathogens by macrophages, providing a theoretical basis for understanding its role in innate immunity.

10.
Exp Cell Res ; 442(1): 114192, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39127439

RESUMEN

N6-methyladenosine (m6A) alteration is an epigenetic regulator widely involved in the tumorigenicity of hepatocellular carcinoma (HCC). The role of YTH N6-methyladenosine RNA binding protein F3 (YTHDF3), an m6A reader in HCC, requires further investigation. Here, we aim to explore the biological properties of YTHDF3 in HCC and its potential mechanisms. The predictive risk model for HCC was developed by analyzing the expression of genes associated with m6A in HCC using online datasets. WB and qPCR were employed to assess YTHDF3 expression in HCC and its correlation with the disease's clinicopathological characteristics. Both in vitro and in vivo methods were utilized to evaluate the biological effects of YTHDF3 in HCC. The potential targets of YTHDF3 were identified and confirmed using RNA-seq, meRIP-seq, and linear amplification and sequencing of cDNA ends (Lace-seq). We confirmed that YTHDF3 is overexpressed in HCC. Patients with higher YTHDF3 expression had a greater risk of cancer recurrence. In both in vitro and in vivo settings, YTHDF3 boosts the migration and invasion capabilities of HCC cells. Through multi-omics research, we identified YTHDF3's downstream target genes as NKD inhibitors of the WNT signaling pathway 1 (NKD1) and the WNT/ß-catenin signaling pathway. With m6A modification, YTHDF3 suppresses the transcription and translation of NKD1. Additionally, NKD1 inhibited tumor growth by blocking the WNT/ß-catenin signaling pathway. The investigation found that the oncogene YTHDF3 stimulates the WNT/ß-catenin signaling pathway by m6A-dependently suppressing NKD1 expression in HCC cells. Our findings suggest that YTHDF3 regulates hepatocarcinogenesis, providing fresh perspectives on potential biomarkers and therapeutic targets for HCC.


Asunto(s)
Adenosina , Carcinoma Hepatocelular , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas , Invasividad Neoplásica , Proteínas de Unión al ARN , Vía de Señalización Wnt , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Humanos , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Vía de Señalización Wnt/genética , Animales , Ratones , Adenosina/análogos & derivados , Adenosina/metabolismo , Regulación Neoplásica de la Expresión Génica/genética , Invasividad Neoplásica/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proliferación Celular/genética , Movimiento Celular/genética , Línea Celular Tumoral , Ratones Desnudos , beta Catenina/metabolismo , beta Catenina/genética , Ratones Endogámicos BALB C , Masculino , Metástasis de la Neoplasia , Proteínas de Unión al Calcio
11.
Proc Natl Acad Sci U S A ; 119(26): e2121174119, 2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35727969

RESUMEN

The carbon-neutral synthesis of syngas from CO2 and H2O powered by solar energy holds grand promise for solving critical issues such as global warming and the energy crisis. Here we report photochemical reduction of CO2 with H2O into syngas using core/shell Au@Cr2O3 dual cocatalyst-decorated multistacked InGaN/GaN nanowires (NWs) with sunlight as the only energy input. First-principle density functional theory calculations revealed that Au and Cr2O3 are synergetic in deforming the linear CO2 molecule to a bent state with an O-C-O angle of 116.5°, thus significantly reducing the energy barrier of CO2RR compared with that over a single component of Au or Cr2O3. Hydrogen evolution reaction was promoted by the same cocatalyst simultaneously. By combining the cooperative catalytic properties of Au@Cr2O3 with the distinguished optoelectronic virtues of the multistacked InGaN NW semiconductor, the developed photocatalyst demonstrated high syngas activity of 1.08 mol/gcat/h with widely tunable H2/CO ratios between 1.6 and 9.2 under concentrated solar light illumination. Nearly stoichiometric oxygen was evolved from water splitting at a rate of 0.57 mol/gcat/h, and isotopic testing confirmed that syngas originated from CO2RR. The solar-to-syngas energy efficiency approached 0.89% during overall CO2 reduction coupled with water splitting. The work paves a way for carbon-neutral synthesis of syngas with the sole inputs of CO2, H2O, and solar light.

12.
Proc Natl Acad Sci U S A ; 119(42): e2207326119, 2022 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-36215478

RESUMEN

Electrochemical conversion of CO2 into formate is a promising strategy for mitigating the energy and environmental crisis, but simultaneously achieving high selectivity and activity of electrocatalysts remains challenging. Here, we report low-dimensional SnO2 quantum dots chemically coupled with ultrathin Ti3C2Tx MXene nanosheets (SnO2/MXene) that boost the CO2 conversion. The coupling structure is well visualized and verified by high-resolution electron tomography together with nanoscale scanning transmission X-ray microscopy and ptychography imaging. The catalyst achieves a large partial current density of -57.8 mA cm-2 and high Faradaic efficiency of 94% for formate formation. Additionally, the SnO2/MXene cathode shows excellent Zn-CO2 battery performance, with a maximum power density of 4.28 mW cm-2, an open-circuit voltage of 0.83 V, and superior rechargeability of 60 h. In situ X-ray absorption spectroscopy analysis and first-principles calculations reveal that this remarkable performance is attributed to the unique and stable structure of the SnO2/MXene, which can significantly reduce the reaction energy of CO2 hydrogenation to formate by increasing the surface coverage of adsorbed hydrogen.

13.
Mol Cancer ; 23(1): 55, 2024 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-38491348

RESUMEN

BACKGROUND: Long noncoding RNAs (lncRNAs) have emerged as key players in tumorigenesis and tumour progression. However, the biological functions and potential mechanisms of lncRNAs in colorectal cancer (CRC) are unclear. METHODS: The novel lncRNA POU6F2-AS1 was identified through bioinformatics analysis, and its expression in CRC patients was verified via qRT-PCR and FISH. In vitro and in vivo experiments, such as BODIPY staining, Oil Red O staining, triglyceride (TAG) assays, and liquid chromatography mass spectrometry (LC-MS) were subsequently performed with CRC specimens and cells to determine the clinical significance, and functional roles of POU6F2-AS1. Biotinylated RNA pull-down, RIP, Me-RIP, ChIP, and patient-derived organoid (PDO) culture assays were performed to confirm the underlying mechanism of POU6F2-AS1. RESULTS: The lncRNA POU6F2-AS1 is markedly upregulated in CRC and associated with adverse clinicopathological features and poor overall survival in CRC patients. Functionally, POU6F2-AS1 promotes the growth and lipogenesis of CRC cells both in vitro and in vivo. Mechanistically, METTL3-induced m6A modification is involved in the upregulation of POU6F2-AS1. Furthermore, upregulated POU6F2-AS1 could tether YBX1 to the FASN promoter to induce transcriptional activation, thus facilitating the growth and lipogenesis of CRC cells. CONCLUSIONS: Our data revealed that the upregulation of POU6F2-AS1 plays a critical role in CRC fatty acid metabolism and might provide a novel promising biomarker and therapeutic target for CRC.


Asunto(s)
Neoplasias Colorrectales , MicroARNs , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Regulación hacia Arriba , Línea Celular Tumoral , Proliferación Celular/genética , MicroARNs/genética , Neoplasias Colorrectales/patología , Ácidos Grasos , Regulación Neoplásica de la Expresión Génica , Movimiento Celular/genética , Factores del Dominio POU/genética , Factores del Dominio POU/metabolismo , Metiltransferasas/metabolismo , Acido Graso Sintasa Tipo I/genética , Acido Graso Sintasa Tipo I/metabolismo
14.
Angiogenesis ; 27(3): 351-373, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38498232

RESUMEN

Age-related macular degeneration (AMD) is a common retinal neurodegenerative disease among the elderly. Neovascular AMD (nAMD), a leading cause of AMD-related blindness, involves choroidal neovascularization (CNV), which can be suppressed by anti-angiogenic treatments. However, current CNV treatments do not work in all nAMD patients. Here we investigate a novel target for AMD. Granzyme B (GzmB) is a serine protease that promotes aging, chronic inflammation and vascular permeability through the degradation of the extracellular matrix (ECM) and tight junctions. Extracellular GzmB is increased in retina pigment epithelium (RPE) and mast cells in the choroid of the healthy aging outer retina. It is further increased in donor eyes exhibiting features of nAMD and CNV. Here, we show in RPE-choroidal explant cultures that exogenous GzmB degrades the RPE-choroid ECM, promotes retinal/choroidal inflammation and angiogenesis while diminishing anti-angiogenic factor, thrombospondin-1 (TSP-1). The pharmacological inhibition of either GzmB or mast-cell degranulation significantly reduces choroidal angiogenesis. In line with our in vitro data, GzmB-deficiency reduces the extent of laser-induced CNV lesions and the age-related deterioration of electroretinogram (ERG) responses in mice. These findings suggest that targeting GzmB, a serine protease with no known endogenous inhibitors, may be a potential novel therapeutic approach to suppress CNV in nAMD.


Asunto(s)
Neovascularización Coroidal , Matriz Extracelular , Granzimas , Inflamación , Mastocitos , Epitelio Pigmentado de la Retina , Granzimas/metabolismo , Neovascularización Coroidal/metabolismo , Neovascularización Coroidal/patología , Animales , Matriz Extracelular/metabolismo , Matriz Extracelular/patología , Humanos , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/patología , Inflamación/patología , Inflamación/metabolismo , Ratones , Mastocitos/metabolismo , Mastocitos/patología , Mastocitos/enzimología , Trombospondina 1/metabolismo , Trombospondina 1/genética , Ratones Endogámicos C57BL , Coroides/patología , Coroides/metabolismo , Coroides/irrigación sanguínea , Degeneración Macular/patología , Degeneración Macular/metabolismo , Ratones Noqueados
15.
Am J Transplant ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39155023

RESUMEN

We evaluated the liver transplantation (LT) criteria in acute-on-chronic liver failure (ACLF), incorporating an urgent living-donor LT (LDLT) program. Critically ill patients with a Chronic Liver Failure Consortium (CLIF-C) ACLF score (CLIF-C_ACLF_score) ≥65, previously considered unsuitable for LT, were included to explore the excess mortality threshold of the CLIF-C_ACLF_score (CLIF-C_ACLF_score_threshold). We followed 854 consecutive patients with ACLF (276 ACLF grade 2 and 215 ACLF grade 3) over 10 years among 4432 LT recipients between 2008 and 2019. For advanced ACLF patients without immediate deceased-donor (DD) allocation, an urgent LDLT program was expedited. The CLIF-C_ACLF_score_threshold was determined by the metrics of transplant survival benefit: >60% 1-year and >50% 5-year survival rate. In predicting post-LT mortality, the CLIF-C_ACLF_score outperformed the (model for end-stage liver disease-sodium) MELD-Na and (model for end-stage liver disease) MELD-3.0 scores but was comparable to the Sundaram ACLF-LT-mortality score. A CLIF-C_ACLF_score ≥65 (n = 54) demonstrated posttransplant survival benefits, with 1-year and 5-year survival rates of 66.7% and 50.4% (P < .001), respectively. Novel CLIF-C_ACLF_score_threshold for 1-year and 5-year mortalities was 70 and 69, respectively. A CLIF-C_ACLF_score-based nomogram for predicting survival probabilities, integrating cardiovascular disease, diabetes, and donor type (LDLT vs DDLT), was generated. This study suggests reconsidering the criteria for unsuitable LT with a CLIF-C_ACLF_score ≥65. Implementing a timely salvage LT strategy, and incorporating urgent LDLT, can enhance survival rates.

16.
Anal Chem ; 96(16): 6186-6194, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38594223

RESUMEN

Solvatochromes have gained great attention because of their unique roles in monitoring biomolecular location, interaction, and dynamics. Particularly, solvatochromes presenting both red-shifting excitation and dual-band switchable emission are in great demand yet significantly difficult to come true. In this article, we disclose an aromatic alcohol-based pH-sensitive chromophore NIR-HBT that not only presents red-shifting excitation and solvent-dependent dual-band emission but also shows high photostability and excellent brightness. To the best of our knowledge, this is the first solvatochrome to simultaneously display these optical properties. Especially, in contrast to the reported dual-band solvatochromes whose solvatochromism is achieved by affecting their excited state behaviors, the solvatochromism of NIR-HBT is realized by modulating its ground state proton dissociation, which is a new solvatochromic mechanism that has not been reported. Furthermore, based on the dual-band solvatochromism of NIR-HBT and its intrinsic binding ability to GQs, near-infrared ratiometric detection of GQs is achieved. These results indicate that NIR-HBT is an attractive solvatochrome that can be used to develop near-infrared ratiometric biosensors for biological research. More broadly, the discovered solvatochromic mechanism can also open new horizons for exploring the solvatochrome.

17.
Cancer Immunol Immunother ; 73(2): 40, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38340166

RESUMEN

BACKGROUND: Dynamin-related protein 1 (Drp1)-mediated mitochondrial fission plays important roles in the activation, proliferation, and migration of T cells. METHODS: We investigated the synergistic effect of Drp1-mediated T cell antitumor activities and programmed cell death protein 1 (PD-1) blockade for treating lung cancer through in vitro co-culture experiments and an in vivo nude mouse xenograft model. RESULTS: High expression levels of Drp1 positively regulated T cell activation, enhanced T cell-induced suppression of lung cancer cells, promoted CD8+ T cell infiltration in the tumor and spleen, and significantly enhanced the antitumor immune response of the PD-1 inhibitor pembrolizumab. The mechanism of this synergistic antitumor effect involved the secretion of immune killing-related cytokines and the regulation of the PD-1-ERK/Drp1 pathway in T cells. CONCLUSIONS: Our findings suggest that modifying Drp1 expression in T cells could serve as a potential therapeutic target for enhancing the antitumor immune response in future immunotherapies.


Asunto(s)
Dinaminas , Inhibidores de Puntos de Control Inmunológico , Neoplasias Pulmonares , Animales , Humanos , Ratones , Linfocitos T CD8-positivos , Dinaminas/metabolismo , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Receptor de Muerte Celular Programada 1
18.
Small ; 20(38): e2400173, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38822718

RESUMEN

Perovskite solar cells, recognized for their high photovoltaic conversion efficiency (PCE), cost-effectiveness, and simple fabrication, face challenges in PCE improvement due to structural defects in polycrystalline films. This study introduces a novel fabrication method for perovskite films using methylammonium chloride (MACl) to align grain orientation uniformly, followed by a high-pressure process to merge these grains into a texture resembling single-crystal perovskite. Employing advanced visual fluorescence microscopy, charge dynamics in these films are analyzed, uncovering the significant impact of grain boundaries on photo-generated charge transport within perovskite crystals. A key discovery is that optimal charge transport efficiency and speed occur in grain centers when the grain size exceeds 10 µm, challenging the traditional view that efficiency peaks when grain size surpasses film thickness to form a monolayer. Additionally, the presence of large-sized grains enhances ion activation energy, reducing ion migration under light and improving resistance to photo-induced degradation. In application, a perovskite solar cell module with large grains achieve a PCE of 22.45%, maintaining performance with no significant degradation under continuous white LED light at 100 mA cm-2 for over 1000 h. This study offers a new approach to perovskite film fabrication and insights into optimizing perovskite solar cell modules.

19.
Small ; 20(25): e2309906, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38221704

RESUMEN

On-site hydrogen production from liquid organic hydrogen carriers e.g., methanol provides an emerging strategy for the safe storage and transportation of hydrogen. Herein, a catalytic architecture consisting of nickel-cobalt nanoclusters dispersed on gallium nitride nanowires supported by silicon for light-driven hydrogen production from methanol is reported. By correlative microscopic, spectroscopic characterizations, and density functional theory calculations, it is revealed that NiCo nanoclusters work in synergy with GaN nanowires to enable the achievement of a significantly reduced activation energy of methanol dehydrogenation by switching the potential-limiting step from *CHO → *CO to *CH3O → *CH2O. In combination with the marked photothermal effect, a high hydrogen rate of 5.62 mol·gcat-1·h-1 with a prominent turnover frequency of 43,460 h-1 is achieved at 5 Wcm-2 without additional energy input. Remarkably, the synergy between Co and Ni, in combination with the unique surface of GaN, renders the architecture with outstanding resistance to sintering and coking. The architecture thereby exhibits a high turnover number of >16,310,000 over 600 h. Outdoor testing validates the viability of the architecture for active and robust hydrogen evolution under natural concentrated sunlight. Overall, this work presents a promising architecture for on-site hydrogen production from CH3OH by virtually unlimited solar energy.

20.
Semin Thromb Hemost ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950598

RESUMEN

The optimal pharmacological prophylaxis for venous thromboembolism (VTE) after hip or knee arthroplasty is uncertain. We conducted a systematic review and network meta-analysis to compare the efficacy and safety of various medications. We searched multiple databases for randomized clinical trials (RCTs) comparing medications (including factor Xa inhibitors, factor IIa inhibitor, warfarin, unfractionated heparin [UFH], low-molecular-weight heparin [LMWH], aspirin, pentasaccharide) for VTE prophylaxis post-arthroplasty. Outcomes included any postoperative VTE identified with screening, major bleeding, and death. We used LMWH as the main comparator for analysis and performed trial sequential analysis (TSA) for each pairwise comparison. Certainty of evidence was assessed using GRADE (Grading of Recommendations, Assessments, Developments and Evaluations). We analyzed 70 RCTs (55,841 participants). Factor Xa inhibitors decreased postoperative VTE significantly compared with LMWH (odds ratio [OR]: 0.55, 95% confidence interval [CI]: 0.44-0.68, high certainty). Pentasaccharides probably reduce VTE (OR: 0.61, 95% CI: 0.36-1.02, moderate certainty), while the factor IIa inhibitor dabigatran may reduce VTE (OR: 0.75, 95% CI: 0.40-1.42, low certainty). UFH probably increases VTE compared with LMWH (OR: 1.31, 95% CI: 0.91-1.89, moderate certainty), and other agents like warfarin, aspirin, placebo, and usual care without thromboprophylaxis increase VTE (high certainty). Factor Xa inhibitors may not significantly affect major bleeding compared with LMWH (OR: 1.06, 95% CI: 0.81-1.39, low certainty). No medications had a notable effect on mortality compared with LMWH (very low certainty). TSA suggests sufficient evidence for the benefit of factor Xa inhibitors over LMWH for VTE prevention. Compared with LMWH and aspirin, factor Xa inhibitors are associated with reduced VTE after hip or knee arthroplasty, without an increase in bleeding and likely no impact on mortality.

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