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1.
Cell ; 184(11): 2955-2972.e25, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34019795

RESUMO

Natural antibodies (Abs) can target host glycans on the surface of pathogens. We studied the evolution of glycan-reactive B cells of rhesus macaques and humans using glycosylated HIV-1 envelope (Env) as a model antigen. 2G12 is a broadly neutralizing Ab (bnAb) that targets a conserved glycan patch on Env of geographically diverse HIV-1 strains using a unique heavy-chain (VH) domain-swapped architecture that results in fragment antigen-binding (Fab) dimerization. Here, we describe HIV-1 Env Fab-dimerized glycan (FDG)-reactive bnAbs without VH-swapped domains from simian-human immunodeficiency virus (SHIV)-infected macaques. FDG Abs also recognized cell-surface glycans on diverse pathogens, including yeast and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike. FDG precursors were expanded by glycan-bearing immunogens in macaques and were abundant in HIV-1-naive humans. Moreover, FDG precursors were predominately mutated IgM+IgD+CD27+, thus suggesting that they originated from a pool of antigen-experienced IgM+ or marginal zone B cells.


Assuntos
Anticorpos Neutralizantes/imunologia , HIV-1/imunologia , Fragmentos Fab das Imunoglobulinas/imunologia , Polissacarídeos/imunologia , SARS-CoV-2/imunologia , Vírus da Imunodeficiência Símia/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Animais , Linfócitos B/imunologia , Anticorpos Amplamente Neutralizantes/imunologia , COVID-19/imunologia , Dimerização , Epitopos/imunologia , Glicosilação , Anticorpos Anti-HIV/imunologia , Infecções por HIV/imunologia , Humanos , Fragmentos Fab das Imunoglobulinas/química , Macaca mulatta , Polissacarídeos/química , Receptores de Antígenos de Linfócitos B/química , Vírus da Imunodeficiência Símia/genética , Vacinas/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/química , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética
2.
Nat Immunol ; 18(12): 1361, 2017 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-29144498

RESUMO

This corrects the article DOI: 10.1038/ni.3830.

3.
Nat Immunol ; 18(10): 1094-1103, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28846086

RESUMO

DEAD-box (DDX) helicases are vital for the recognition of RNA and metabolism and are critical for the initiation of antiviral innate immunity. Modification of RNA is involved in many biological processes; however, its role in antiviral innate immunity has remained unclear. Here we found that nuclear DDX member DDX46 inhibited the production of type I interferons after viral infection. DDX46 bound Mavs, Traf3 and Traf6 transcripts (which encode signaling molecules involved in antiviral responses) via their conserved CCGGUU element. After viral infection, DDX46 recruited ALKBH5, an 'eraser' of the RNA modification N6-methyladenosine (m6A), via DDX46's DEAD helicase domain to demethylate those m6A-modified antiviral transcripts. It consequently enforced their retention in the nucleus and therefore prevented their translation and inhibited interferon production. DDX46 also suppressed antiviral innate immunity in vivo. Thus, DDX46 inhibits antiviral innate responses by entrapping selected antiviral transcripts in the nucleus by erasing their m6A modification, a modification normally required for export from the nucleus and translation.


Assuntos
Adenina/análogos & derivados , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Imunidade Inata/genética , Transcrição Gênica , Adenina/metabolismo , Homólogo AlkB 5 da RNA Desmetilase/genética , Homólogo AlkB 5 da RNA Desmetilase/metabolismo , Animais , Sítios de Ligação , Linhagem Celular , Núcleo Celular/metabolismo , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Interferon Tipo I/biossíntese , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Motivos de Nucleotídeos , Ligação Proteica , Transporte de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Estomatite Vesicular/genética , Estomatite Vesicular/imunologia , Estomatite Vesicular/metabolismo , Vesiculovirus/fisiologia , Replicação Viral
4.
Nature ; 605(7910): 561-566, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35545668

RESUMO

NPR1 is a master regulator of the defence transcriptome induced by the plant immune signal salicylic acid1-4. Despite the important role of NPR1 in plant immunity5-7, understanding of its regulatory mechanisms has been hindered by a lack of structural information. Here we report cryo-electron microscopy and crystal structures of Arabidopsis NPR1 and its complex with the transcription factor TGA3. Cryo-electron microscopy analysis reveals that NPR1 is a bird-shaped homodimer comprising a central Broad-complex, Tramtrack and Bric-à-brac (BTB) domain, a BTB and carboxyterminal Kelch helix bundle, four ankyrin repeats and a disordered salicylic-acid-binding domain. Crystal structure analysis reveals a unique zinc-finger motif in BTB for interacting with ankyrin repeats and mediating NPR1 oligomerization. We found that, after stimulation, salicylic-acid-induced folding and docking of the salicylic-acid-binding domain onto ankyrin repeats is required for the transcriptional cofactor activity of NPR1, providing a structural explanation for a direct role of salicylic acid in regulating NPR1-dependent gene expression. Moreover, our structure of the TGA32-NPR12-TGA32 complex, DNA-binding assay and genetic data show that dimeric NPR1 activates transcription by bridging two fatty-acid-bound TGA3 dimers to form an enhanceosome. The stepwise assembly of the NPR1-TGA complex suggests possible hetero-oligomeric complex formation with other transcription factors, revealing how NPR1 reprograms the defence transcriptome.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Microscopia Crioeletrônica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Imunidade Vegetal , Proteínas de Plantas/metabolismo , Ácido Salicílico/metabolismo , Fatores de Transcrição/metabolismo
5.
Nat Methods ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251798

RESUMO

Cryo-electron tomography allows the routine visualization of cellular landscapes in three dimensions at nanometer-range resolutions. When combined with single-particle tomography, it is possible to obtain near-atomic resolution structures of frequently occurring macromolecules within their native environment. Two outstanding challenges associated with cryo-electron tomography/single-particle tomography are the automatic identification and localization of proteins, tasks that are hindered by the molecular crowding inside cells, imaging distortions characteristic of cryo-electron tomography tomograms and the sheer size of tomographic datasets. Current methods suffer from low accuracy, demand extensive and time-consuming manual labeling or are limited to the detection of specific types of proteins. Here, we present MiLoPYP, a two-step dataset-specific contrastive learning-based framework that enables fast molecular pattern mining followed by accurate protein localization. MiLoPYP's ability to effectively detect and localize a wide range of targets including globular and tubular complexes as well as large membrane proteins, will contribute to streamline and broaden the applicability of high-resolution workflows for in situ structure determination.

6.
Proc Natl Acad Sci U S A ; 121(32): e2314087121, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39083421

RESUMO

Invasive fungal diseases are a major threat to human health, resulting in more than 1.5 million annual deaths worldwide. The arsenal of antifungal therapeutics remains limited and is in dire need of drugs that target additional biosynthetic pathways that are absent from humans. One such pathway involves the biosynthesis of trehalose. Trehalose is a disaccharide that is required for pathogenic fungi to survive in their human hosts. In the first step of trehalose biosynthesis, trehalose-6-phosphate synthase (Tps1) converts UDP-glucose and glucose-6-phosphate to trehalose-6-phosphate. Here, we report the structures of full-length Cryptococcus neoformans Tps1 (CnTps1) in unliganded form and in complex with uridine diphosphate and glucose-6-phosphate. Comparison of these two structures reveals significant movement toward the catalytic pocket by the N terminus upon ligand binding and identifies residues required for substrate binding, as well as residues that stabilize the tetramer. Intriguingly, an intrinsically disordered domain (IDD), which is conserved among Cryptococcal species and closely related basidiomycetes, extends from each subunit of the tetramer into the "solvent" but is not visible in density maps. We determined that the IDD is not required for C. neoformans Tps1-dependent thermotolerance and osmotic stress survival. Studies with UDP-galactose highlight the exquisite substrate specificity of CnTps1. In toto, these studies expand our knowledge of trehalose biosynthesis in Cryptococcus and highlight the potential of developing antifungal therapeutics that disrupt the synthesis of this disaccharide or the formation of a functional tetramer and the use of cryo-EM in the structural characterization of CnTps1-ligand/drug complexes.


Assuntos
Antifúngicos , Cryptococcus neoformans , Glucosiltransferases , Trealose , Cryptococcus neoformans/enzimologia , Cryptococcus neoformans/metabolismo , Cryptococcus neoformans/genética , Glucosiltransferases/metabolismo , Glucosiltransferases/genética , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/metabolismo , Trealose/metabolismo , Trealose/análogos & derivados , Trealose/biossíntese , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/química , Modelos Moleculares , Humanos , Domínio Catalítico , Cristalografia por Raios X
7.
Nat Methods ; 20(12): 1909-1919, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37884796

RESUMO

Single-particle cryo-electron tomography is an emerging technique capable of determining the structure of proteins imaged within the native context of cells at molecular resolution. While high-throughput techniques for sample preparation and tilt-series acquisition are beginning to provide sufficient data to allow structural studies of proteins at physiological concentrations, the complex data analysis pipeline and the demanding storage and computational requirements pose major barriers for the development and broader adoption of this technology. Here, we present a scalable, end-to-end framework for single-particle cryo-electron tomography data analysis from on-the-fly pre-processing of tilt series to high-resolution refinement and classification, which allows efficient analysis and visualization of datasets with hundreds of tilt series and hundreds of thousands of particles. We validate our approach using in vitro and cellular datasets, demonstrating its effectiveness at achieving high-resolution and revealing conformational heterogeneity in situ. The framework is made available through an intuitive and easy-to-use computer application, nextPYP ( http://nextpyp.app ).


Assuntos
Tomografia com Microscopia Eletrônica , Software , Tomografia com Microscopia Eletrônica/métodos , Microscopia Crioeletrônica/métodos , Proteínas , Processamento de Imagem Assistida por Computador/métodos
8.
Nano Lett ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856668

RESUMO

Cell membrane-based nanovesicles (CMNVs) play pivotal roles in biomolecular transportation in living organisms and appear as attractive bioinformed nanomaterials for theranostic applications. However, the current surface-engineering technologies are limited in flexibility and orthogonality, making it challenging to simultaneously display multiple different ligands on the CMNV surface in a precisely controlled manner. Here, we developed a DNA scaffold-programmed approach to orthogonally engineer CMNVs with versatile ligands. The designed DNA scaffolds can rapidly anchor onto the CMNV surface, and their unique sequences and hybridized properties enable independent control of the loading of multiple different types of biomolecules on the CMNVs. As a result, the orthogonal engineering of CMNVs with a renal targeted peptide and a therapeutic protein at controlled ratios demonstrated an enhanced renal targeting and repair potential in vivo. This study highlights that a DNA scaffold-programmed platform can provide a potent means for orthogonal and flexible surface engineering of CMNVs for diverse therapeutic purposes.

9.
Small ; 20(10): e2305594, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37919857

RESUMO

Diabetic alveolar bone defect (DABD) causes persistent bacterial infection, prolonged inflammation, and delayed bone healing, making it a considerable clinical challenge. In this study, by integrating silver nanoclusters (AgNCs) and M2 macrophage-derived extracellular vesicles (M2EVs), a multifunctional DNA-based hydrogel, called Agevgel, is developed with antibacterial, anti-inflammatory, immunomodulatory, and osteogenic properties to promote DABD rebuilding. AgNCs are tightly embedded into the DNA scaffolds and exhibit effective anti-bacterial activity, while immunomodulatory M2EVs are encapsulated within the shape-variable DNA scaffolds and exhibit potent anti-inflammatory and osteogenic properties. The results reveal that Agevgel effectively prolongs the local retention time and bioactivity of M2EVs in vivo. In particular, the sustained release of M2EVs can last for at least 7 days when applying Agevgel to DABD. Compared to free M2EVs or Aggel (AgNCs encapsulated within the DNA hydrogel) treatments, the Agevgel treatment accelerates the defect healing rate of alveolar bone and dramatically improves the trabecular architecture. Mechanistically, Agevgel plays a key role in regulating macrophage polarization and promoting the expression of proliferative and osteogenic factors. In summary, Agevgel provides a comprehensive treatment strategy for DABD with a great clinical translational value, highlighting the application of DNA hydrogels as an ideal bioscaffolds for periodontal diseases.


Assuntos
Diabetes Mellitus , Procedimentos de Cirurgia Plástica , Hidrogéis , Cicatrização , Antibacterianos , DNA , Anti-Inflamatórios
10.
Mol Carcinog ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016629

RESUMO

Hepatocellular carcinoma (HCC) is a common malignant tumor. Histone lactylation, a novel epigenetic modification, plays a crucial role in various cancers. However, the functional role and underlying mechanism of histone lactylation in HCC progression have not yet been investigated. Histone lactylation levels in HCC tissues and cells were assessed using a densitometric kit and western blot analysis. The role of histone lactylation in cell malignant phenotypes was determined through functional assays in vitro, and a xenograft tumor model was established to verify the function of histone lactylation in vivo. ChIP assay was performed to explore the interaction between histone lactylation and endothelial cell-specific molecule 1 (ESM1). Additionally, gain-and-loss-of-function assays were conducted to investigate the regulatory role of ESM1 in HCC pathogenesis. Histone lactylation levels were increased in HCC tissues and cells, and H3K9 lactylation (H3K9la) and H3K56 lactylation (H3K56la) were identified as the histone modification sites. We observed that H3K9la and H3K56la caused abnormal histone lactylation and were associated with poor prognosis. Functionally, histone lactylation was found to promote HCC cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) process in vitro. However, histone lactylation inhibition with 2-deoxy-d-glucose (2-DG) reduced the malignant phenotypes of HCC cells. In vivo, 2-DG treatment reduced tumor growth and metastasis in the HCC mouse model. Mechanistically, it was revealed that histone lactylation activated ESM1 transcription in HCC cells. ESM1 was expressed at a high level in HCC and exerted a carcinogenic role. Histone lactylation facilitates cell malignant phenotypes, tumor growth, and metastasis by upregulating ESM1 expression in HCC, which reveals the downstream molecular mechanism of histone lactylation and might provide a novel therapeutic target for HCC therapy.

11.
Hepatology ; 77(4): 1106-1121, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35344606

RESUMO

BACKGROUND AND AIMS: Hepatocarcinogenesis goes through HCC progenitor cells (HcPCs) to fully established HCC, and the mechanisms driving the development of HcPCs are still largely unknown. APPROACH AND RESULTS: Proteomic analysis in nonaggregated hepatocytes and aggregates containing HcPCs from a diethylnitrosamine-induced HCC mouse model was screened using a quantitative mass spectrometry-based approach to elucidate the dysregulated proteins in HcPCs. The heterotrimeric G stimulating protein α subunit (GαS) protein level was significantly increased in liver cancer progenitor HcPCs, which promotes their response to oncogenic and proinflammatory cytokine IL-6 and drives premalignant HcPCs to fully established HCC. Mechanistically, GαS was located at the membrane inside of hepatocytes and acetylated at K28 by acetyltransferase lysine acetyltransferase 7 (KAT7) under IL-6 in HcPCs, causing the acyl protein thioesterase 1-mediated depalmitoylation of GαS and its cytoplasmic translocation, which were determined by GαS K28A mimicking deacetylation or K28Q mimicking acetylation mutant mice and hepatic Kat7 knockout mouse. Then, cytoplasmic acetylated GαS associated with signal transducer and activator of transcription 3 (STAT3) to impede its interaction with suppressor of cytokine signaling 3, thus promoting in a feedforward manner STAT3 phosphorylation and the response to IL-6 in HcPCs. Clinically, GαS, especially K28-acetylated GαS, was determined to be increased in human hepatic premalignant dysplastic nodules and positively correlated with the enhanced STAT3 phosphorylation, which were in accordance with the data obtained in mouse models. CONCLUSIONS: Malignant progression of HcPCs requires increased K28-acetylated and cytoplasm-translocated GαS, causing enhanced response to IL-6 and driving premalignant HcPCs to fully established HCC, which provides mechanistic insight and a potential target for preventing hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Lisina Acetiltransferases , Humanos , Camundongos , Animais , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/patologia , Interleucina-6/metabolismo , Proteômica , Citoplasma/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Lisina Acetiltransferases/metabolismo , Fator de Transcrição STAT3/metabolismo , Histona Acetiltransferases/metabolismo
12.
J Med Virol ; 96(9): e29889, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39206862

RESUMO

The SARS-CoV-2 Omicron variant is characterized by its high transmissibility, which has caused a worldwide epidemiological event. Yet, it turns ominous once the disease progression degenerates into severe pneumonia and sepsis, presenting a horrendous lethality. To elucidate the alveolar immune or inflammatory landscapes of Omicron critical-ill patients, we performed single-cell RNA-sequencing (scRNA-seq) of bronchoalveolar lavage fluid (BALF) from the patients with critical pneumonia caused by Omicron infection, and analyzed the correlation between the clinical severity scores and different immune cell subpopulations. In the BALF of Omicron critical patients, the alveolar violent myeloid inflammatory environment was determined. ISG15+ neutrophils and CXCL10+ macrophages, both expressed the interferon-stimulated genes (ISGs), were negatively correlated with clinical pulmonary infection score, while septic CST7+ neutrophils and inflammatory VCAN+ macrophages were positively correlated with sequential organ failure assessment. The percentages of ISG15+ neutrophils were associated with more protective alveolar epithelial cells, and may reshape CD4+ T cells to the exhaustive phenotype, thus preventing immune injuries. The CXCL10+ macrophages may promote plasmablast/plasma cell survival and activation as well as the production of specific antibodies. As compared to the previous BALF scRNA-seq data from SARS-CoV-2 wild-type/Alpha critical patients, the subsets of neutrophils and macrophages with pro-inflammatory and immunoregulatory features presented obvious distinctions, suggesting an immune disparity in Omicron variants. Overall, this study provides a BALF single-cell atlas of Omicron critical patients, and suggests that alveolar interferon-responsive neutrophils and macrophages may extricate SARS-CoV-2 Omicron critical patients from the nasty fate of sepsis.


Assuntos
Líquido da Lavagem Broncoalveolar , COVID-19 , Macrófagos , Neutrófilos , SARS-CoV-2 , Sepse , Humanos , COVID-19/imunologia , COVID-19/virologia , Neutrófilos/imunologia , Sepse/imunologia , Sepse/virologia , SARS-CoV-2/imunologia , Masculino , Macrófagos/imunologia , Macrófagos/virologia , Feminino , Pessoa de Meia-Idade , Líquido da Lavagem Broncoalveolar/virologia , Líquido da Lavagem Broncoalveolar/imunologia , Líquido da Lavagem Broncoalveolar/citologia , Idoso , Citocinas/imunologia , Interferons , Estado Terminal , Adulto
13.
Insect Mol Biol ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709468

RESUMO

Cordyceps cicadae (Hypocreales: Cordycipitaceae) is a renowned entomopathogenic fungus used as herbal medicine in China. However, wild C. cicadae resources have been threatened by heavy harvesting. We hypothesised that Bombyx mori L. (Lepidoptera: Bombycidae) could be a new alternative to cultivate C. cicadae due to the low cost of rearing. Bacterial communities are crucial for the formation of Cordyceps and for promoting the production of metabolites. To better understand the bacterial community structure associated with Cordyceps, three Claviciptaceae fungi were used to explore the pathogenicity of the silkworms. Here, fifth-instar silkworms were infected with C. cicadae, Cordyceps cateniannulata (Hypocreales: Cordycipitaceae) and Beauveria bassiana (Hypocreales: Cordycipitaceae). Subsequently, we applied high-throughput sequencing to explore the composition of bacterial communities in silkworms. Our results showed that all three fungi were highly pathogenic to silkworms, which suggests that silkworms have the potential to cultivate Cordyceps. After fungal infection, the diversity of bacterial communities in silkworms decreased significantly, and the abundance of Staphylococcus increased in mummified larvae, which may play a role in the death process when the host suffers infection by entomopathogenic fungi. Furthermore, there were high similarities in the bacterial community composition and function in the C. cicadae and C. cateniannulata infected samples, and the phylogenetic analysis suggested that these similarities may be related to the fungal phylogenetic relationship. Our findings reveal that infection with different entomopathogenic fungi affects the composition and function of bacterial communities in silkworms and that the bacterial species associated with Cordyceps are primarily host dependent, while fungal infection affects bacterial abundance.

14.
Neurochem Res ; 49(8): 2131-2147, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38822984

RESUMO

BACKGROUND: Sepsis-associated encephalopathy (SAE) develops in 30-70% of hospitalized patients with sepsis. In intensive care units (ICUs), propofol is often administered to ensure an appropriate level of sedation in mechanically ventilated patients. Ferroptosis is a newly identified mode of cellular death characterized by the peroxidation of membrane lipids and excessive iron. This study was conducted to explore the interplay between propofol, sepsis, and ferroptosis. METHODS: An acute systemic inflammatory model was constructed via the intraperitoneal administration of lipopolysaccharide (LPS). Nissl and Fluoro-Jade C (FJC) staining were employed to display neuronal damage and degeneration. Western blotting and immunofluorescence (IF) staining of Bax and Bcl-2 were used to confirm the neural apoptosis. QPCR of cytokines and DHE staining were used to indicate neuroinflammation. To validate ferroptosis, we assessed the content of malondialdehyde (MDA), GSH, and tissue iron, accompanied by transcription level of CHAC1, PTGS2 and GPX4. Additionally, we examined the content of acyl-CoA synthetase long-chain family member 4 (ACSL4), xCT (SLC7A11, solute carrier family 7 member 11), and glutathione peroxidase 4 (GPX4). The IF staining of Iba1-labeled microglia and GFAP-marked astrocytes were used to measure the gliosis. Erastin was pre-pretreated to confirm the anti-ferroptotic capability of propofol. ML385 was preconditioned to explore the role of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in propofol-repressed ferroptosis. RESULTS: Propofol dose-dependently inhibited the decrease of Nissl-positive neurons and the increase of FJC-stained neurons in septic hippocampus and cortex. Neural cytokines, oxidative stress, apoptosis and gliosis were reduced by propofol. Propofol repressed the level of MDA, iron, CHAC1, PTGS2, ACLS4 and restored the content of GSH, GPX4, xCT, Nrf2 and HO-1, thus inhibiting sepsis-induced ferroptosis. All protections from propofol could be reversed by eratsin and ML385 pretreatment. CONCLUSION: Propofol protected against sepsis-induced brain damage, neuroinflammation, neuronal apoptosis and gliosis through the activation of the Nrf2/HO-1 axis to combat ferroptosis.


Assuntos
Ferroptose , Fator 2 Relacionado a NF-E2 , Propofol , Ferroptose/efeitos dos fármacos , Ferroptose/fisiologia , Propofol/farmacologia , Propofol/uso terapêutico , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sepse/metabolismo , Sepse/complicações , Sepse/tratamento farmacológico , Lipopolissacarídeos , Encefalopatia Associada a Sepse/metabolismo , Encefalopatia Associada a Sepse/tratamento farmacológico , Encefalopatia Associada a Sepse/prevenção & controle , Heme Oxigenase-1/metabolismo , Heme Oxigenase (Desciclizante)/metabolismo , Proteínas de Membrana/metabolismo , Lesões Encefálicas/metabolismo , Lesões Encefálicas/tratamento farmacológico , Coenzima A Ligases , Sistema y+ de Transporte de Aminoácidos
15.
Langmuir ; 40(1): 721-733, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38147650

RESUMO

Porous electrodes with high specific surface areas have been commonly employed for alkaline water electrolysis. The gas bubbles generated in electrodes due to water electrolysis, however, can screen the reaction sites and hinder reactant transport, thereby deteriorating the performance of electrodes. Hence, an in-depth understanding of the behavior of bubbles in porous electrodes is of great importance. Nevertheless, since porous electrodes are opaque, direct observation of bubbles therein is still a challenge. In this work, we have successfully captured the behavior of bubbles in the pores at the side surfaces of nickel-based porous electrodes. Two types of porous electrodes are employed: the ones with straight pores along the gravitational direction and the ones with tortuous pores. In the porous electrodes with tortuous pores, the moving bubbles are prone to collide with the solid matrix, thereby leading to the accumulation of bubbles in the pores and hence bubble trapping. By contrast, in the porous electrodes with straight pores, bubbles are seldom trapped; and when two bubbles near the wall surfaces coalesce, the merged bubble can jump away from the wall surfaces, releasing more active surfaces for reaction. As a result, the porous electrodes with straight pores, although with lower specific surface areas, are superior to those with tortuous pores. The relationship among the pore structures of porous electrodes, bubble behavior, and electrode performance disclosed in this work provides deep insights into the design of porous electrodes.

16.
J Org Chem ; 89(18): 13071-13076, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39254633

RESUMO

A novel electrocatalytic dimerization of o-aminphenols and a hydrogen borrowing-like cascade for synthesizing N-monoalkylated aminophenoxazinones have been developed. This electrocatalytic reaction uses a constant current mode in an undivided cell and is free of metal catalysis, open to the air, and eco-friendly. In particular, this protocol exhibits a wide substrate range and provides versatile N-monoalkylated aminophenoxazinones in medium to good yields. The results of our mechanistic research reveal that this protocol involves a cascade of electrochemical cyclocondensation of o-aminphenols and the hydrogen transfer process via paired electrolysis.

17.
Anal Bioanal Chem ; 416(8): 1883-1906, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38367042

RESUMO

In this paper, we establish an in situ visualization analysis method to image the spatial distribution of metabolites in different parts (sclerotium, coremium) and different microregions of Cordyceps cicadae (C. cicadae) to achieve the in situ visual characterization of tissues for a variety of metabolites such as nucleosides, amino acids, polysaccharides, organic acids, fatty acids, and so on. The study included LC-MS chemical composition identification, preparation of C. cicadae tissue sections, DEDI-MSI analysis, DESI combined with Q-TOF/MS to obtain high-resolution imaging of mass-to-charge ratio and space, imaging of C. cicadae in positive-negative ion mode with a spatial resolution of 100 µm, and localizing and identifying its chemical compositions based on its precise mass. A total of 62 compounds were identified; nucleosides were mainly distributed in the coremium, L-threonine and DL-isoleucine, and other essential amino acids; peptides were mainly distributed in the sclerotium of C. cicadae; and the rest of the amino acids did not have a clear pattern; sugars and sugar alcohols were mainly distributed in the coremium of C. cicadae; organic acids and fatty acids were distributed in the nucleus of C. cicadae more than in the sclerotium, and the mass spectrometry imaging method is established in the research. The mass spectrometry imaging method established in this study is simple and fast and can visualize and analyse the spatial distribution of metabolites of C. cicadae, which is of great significance in characterizing the metabolic network of C. cicadae, and provides support for the quality evaluation of C. cicadae and the study of the temporal and spatial metabolic network of chemical compounds.


Assuntos
Cordyceps , Distribuição Tecidual , Espectrometria de Massas , Cordyceps/química , Cordyceps/metabolismo , Nucleosídeos/química , Ácidos Graxos/metabolismo , Aminoácidos/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos
18.
Artigo em Inglês | MEDLINE | ID: mdl-38884921

RESUMO

BACKGROUND: Achieving full revascularization via percutaneous coronary intervention (PCI) may enhance the prognosis of individuals diagnosed with acute coronary syndrome (ACS) and multivessel coronary disease (MVD). The present work focused on investigating whether PCI should be performed during staged or index procedures for non-culprit lesions. METHODS: Electronic databases, such as PubMed, EMBASE, the Cochrane Library, and Web of Science, were systematically explored to locate studies contrasting immediate revascularization with staged complete revascularization for patients who experienced ACS and MVD without cardiac shock. The outcome measures comprised major adverse cardiovascular events (MACEs), all-cause mortality, cardiovascular mortality, myocardial infarction (MI), stroke, and unplanned ischemia-driven revascularization (UIDR). RESULTS: Nine randomized controlled trials involving 3550 patients, including 1780 who received immediate complete revascularization (ICR) and 1770 who received staged complete revascularization (SCR), were included in the analysis. The ICR group had lower MACEs (RR: 0.73, 95% CI: 0.61~0.87, P = 0.0004), MI (RR: 0.53, 95% CI: 0.37~0.77, P = 0.0008), and UIDR (RR: 0.64, 95% CI: 0.50~0.81, P = 0.0003) than did the SCR group. All-cause mortality, CVD incidence, and stroke incidence did not significantly differ between the two groups. According to our subgroup analyses based on the time window of the SCR, the ICR group had significantly fewer MACEs (RR: 0.70, 95% CI: 0.56~0.88, P = 0.003), MI (RR: 0.53, 95% CI: 0.37~0.77, P = 0.0002), and UIDR (RR: 0.56, 95% CI: 0.40~0.77, P = 0.0004) than did the subgroup of patients who were between discharge and 45 days. CONCLUSION: Compared with patients in the SCR group, patients in the ICR group had decreased MACEs, MI, and UIDR, especially between discharge and 45 days. All-cause mortality and CVD incidence were not significantly different between the two groups.

19.
Macromol Rapid Commun ; 45(5): e2300559, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38014713

RESUMO

Alveolar bone injury under diabetic conditions can severely impede many oral disease treatments. Rebuilding diabetic alveolar bone in clinics is currently challenging due to persistent infection and inflammatory response. Here, an antibacterial DNA-based hydrogel named Agantigel is developed by integrating silver nanoclusters (AgNCs) and tumor necrosis factor-alpha (TNF-α) antibody into DNA hydrogel to promote diabetic alveolar bone regeneration. Agantigel can effectively inhibit bacterial growth through AgNCs while exhibiting negligible cytotoxicity in vitro. The sustained release of TNF-α antibody from Agantigel effectively blocks TNF-α and promotes M2 polarization of macrophages, ultimately accelerating diabetic alveolar bone regeneration in vivo. After 21 days of treatment, Agantigel significantly accelerates the defect healing rate of diabetic alveolar bone up to 82.58 ± 8.58% and improves trabecular architectures compared to free TNF-α (42.52 ± 15.85%). The results imply that DNA hydrogels are potential bio-scaffolds helping the sustained release of multidrug for treating DABI or other oral diseases.


Assuntos
Diabetes Mellitus , Hidrogéis , Humanos , Hidrogéis/farmacologia , Fator de Necrose Tumoral alfa , Preparações de Ação Retardada , Antibacterianos/farmacologia , DNA
20.
Nutr Metab Cardiovasc Dis ; 34(3): 590-597, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37996372

RESUMO

BACKGROUND AND AIM: Heart failure (HF) is an important complication of ST-elevation myocardial infarction (STEMI), including early- and late-onset HF. This study aimed to investigate the association between insulin resistance (IR)-related parameters triglyceride glucose (TyG) and TyG-body mass index (TyG-BMI) index and early-onset HF in STEMI between sexes. METHODS AND RESULTS: This cross-sectional study included patients with STEMI who underwent primary percutaneous coronary intervention (PCI) between January 2016 and September 2022. Patients were divided into tertiles according to TyG/TyG-BMI index levels in males and females. The presence of early-onset HF was compared between tertiles in both sexes. Moreover, patients were stratified according to the tertiles of TyG/Tyg-BMI index. Differences in early-onset HF of STEMI were compared between males and females in each tertile group. 1118 patients were included in this study, 20.3% of whom were females. The incidence rate of early-onset HF was significantly higher in females than in males (29% vs. 14.8%). TyG-BMI index was negatively correlated with early-onset HF. In both females and males, there was no difference in the occurrence of early-onset HF between the highest and lowest TyG/TyG-BMI index groups. Sex disparity was observed in females who had a significantly higher prevalence of early-onset HF than males in each TyG/TyG-BMI index tertile group; however, after adjustment, the differences disappeared. CONCLUSIONS: For patients with STEMI who undergo primary PCI, the incidence of early-onset HF is higher in females than in males. The TyG/TyG-BMI index do not contribute to the difference in early-onset HF between sexes.


Assuntos
Insuficiência Cardíaca , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Feminino , Masculino , Humanos , Índice de Massa Corporal , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/epidemiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Estudos Transversais , Intervenção Coronária Percutânea/efeitos adversos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Glucose , Triglicerídeos
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