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1.
Mol Biol Evol ; 41(8)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39041196

RESUMEN

Cyanobacteriota, the sole prokaryotes capable of oxygenic photosynthesis (OxyP), occupy a unique and pivotal role in Earth's history. While the notion that OxyP may have originated from Cyanobacteriota is widely accepted, its early evolution remains elusive. Here, by using both metagenomics and metatranscriptomics, we explore 36 metagenome-assembled genomes from hot spring ecosystems, belonging to two deep-branching cyanobacterial orders: Thermostichales and Gloeomargaritales. Functional investigation reveals that Thermostichales encode the crucial thylakoid membrane biogenesis protein, vesicle-inducing protein in plastids 1 (Vipp1). Based on the phylogenetic results, we infer that the evolution of the thylakoid membrane predates the divergence of Thermostichales from other cyanobacterial groups and that Thermostichales may be the most ancient lineage known to date to have inherited this feature from their common ancestor. Apart from OxyP, both lineages are potentially capable of sulfide-driven AnoxyP by linking sulfide oxidation to the photosynthetic electron transport chain. Unexpectedly, this AnoxyP capacity appears to be an acquired feature, as the key gene sqr was horizontally transferred from later-evolved cyanobacterial lineages. The presence of two D1 protein variants in Thermostichales suggests the functional flexibility of photosystems, ensuring their survival in fluctuating redox environments. Furthermore, all MAGs feature streamlined phycobilisomes with a preference for capturing longer-wavelength light, implying a unique evolutionary trajectory. Collectively, these results reveal the photosynthetic flexibility in these early-diverging cyanobacterial lineages, shedding new light on the early evolution of Cyanobacteriota and their photosynthetic processes.


Asunto(s)
Cianobacterias , Fotosíntesis , Fotosíntesis/genética , Cianobacterias/genética , Cianobacterias/metabolismo , Evolución Biológica , Filogenia , Oxígeno/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Evolución Molecular
2.
Blood ; 142(24): 2079-2091, 2023 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-37595362

RESUMEN

PPM1D encodes a phosphatase that is recurrently activated across cancer, most notably in therapy-related myeloid neoplasms. However, the function of PPM1D in hematopoiesis and its contribution to tumor cell growth remain incompletely understood. Using conditional mouse models, we uncover a central role for Ppm1d in hematopoiesis and validate its potential as a therapeutic target. We find that Ppm1d regulates the competitive fitness and self-renewal of hematopoietic stem cells (HSCs) with and without exogenous genotoxic stresses. We also show that although Ppm1d activation confers cellular resistance to cytotoxic therapy, it does so to a lesser degree than p53 loss, informing the clonal competition phenotypes often observed in human studies. Notably, loss of Ppm1d sensitizes leukemias to cytotoxic therapies in vitro and in vivo, even in the absence of a Ppm1d mutation. Vulnerability to PPM1D inhibition is observed across many cancer types and dependent on p53 activity. Importantly, organism-wide loss of Ppm1d in adult mice is well tolerated, supporting the tolerability of pharmacologically targeting PPM1D. Our data link PPM1D gain-of-function mutations to the clonal expansion of HSCs, inform human genetic observations, and support the therapeutic targeting of PPM1D in cancer.


Asunto(s)
Daño del ADN , Proteína p53 Supresora de Tumor , Adulto , Humanos , Animales , Ratones , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteína Fosfatasa 2C , Mutación , Monoéster Fosfórico Hidrolasas/genética , Ciclo Celular
3.
Stem Cells ; 42(5): 416-429, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38381602

RESUMEN

Cardiovascular diseases (CVDs) are the leading cause of death worldwide, accounting for 31% of all deaths globally. Myocardial ischemia-reperfusion injury (IRI), a common complication of CVDs, is a major cause of mortality and morbidity. Studies have shown efficacious use of mesenchymal stem cells-derived small extracellular vesicles (MSCs-EVs) to mitigate IRI in animals, but few research has been done on human-related models. In this study, human embryonic stem cell-derived chambered cardiac organoid (CCO) was used as a model system to study the effects of MSC-EVs on myocardial IRI. The results revealed that MSC-EVs treatment reduced apoptosis and improved contraction resumption of the CCOs. Metabolomics analysis showed that this effect could be attributed to EVs' ability to prevent the accumulation of unsaturated very long-chain fatty acids (VLCFAs). This was corroborated when inhibition of fatty acid synthase, which was reported to reduce VLCFAs, produced a similar protective effect to EVs. Overall, this study uncovered the mechanistic role of MSC-EVs in mitigating IRI that involves preventing the accumulation of unsaturated VLCFA, decreasing cell death, and improving contraction resumption in CCOs.


Asunto(s)
Apoptosis , Vesículas Extracelulares , Células Madre Mesenquimatosas , Organoides , Humanos , Vesículas Extracelulares/metabolismo , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Organoides/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Daño por Reperfusión Miocárdica/prevención & control , Ácidos Grasos/metabolismo , Cardiotónicos/metabolismo , Cardiotónicos/farmacología
4.
Small ; 20(28): e2309882, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38342670

RESUMEN

Negative therapeutic feedback of inflammation would extensively attenuate the antitumor effect of photodynamic therapy (PDT). In this work, tumor homing chimeric peptide rhomboids (designated as NP-Mel) are fabricated to improve photodynamic performance by inhibiting PDT-upregulated cyclooxygenase-2 (COX-2). The hydrophobic photosensitizer of protoporphyrin IX (PpIX) and palmitic acid are conjugated onto the neuropilin receptors (NRPs) targeting peptide motif (CGNKRTR) to obtain tumor homing chimeric peptide (Palmitic-K(PpIX)CGNKRTR), which can encapsulate the COX-2 inhibitor of meloxicam. The well dispersed NP-Mel not only improves the drug stability and reactive oxygen species (ROS) production ability, but also increase the breast cancer targeted drug delivery to intensify the PDT effect. In vitro and in vivo studies verify that NP-Mel will decrease the secretion of prostaglandin E2 (PGE2) after PDT treatment, inducing the downregulation of IL-6 and TNF-α expressions to suppress PDT induced inflammation. Ultimately, an improved PDT performance of NP-Mel is achieved without inducing obvious systemic toxicity, which might inspire the development of sophisticated nanomedicine in consideration of the feedback induced therapeutic resistance.


Asunto(s)
Ciclooxigenasa 2 , Péptidos , Fotoquimioterapia , Fotoquimioterapia/métodos , Ciclooxigenasa 2/metabolismo , Péptidos/química , Péptidos/farmacología , Animales , Humanos , Línea Celular Tumoral , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Especies Reactivas de Oxígeno/metabolismo , Femenino , Meloxicam/farmacología , Meloxicam/uso terapéutico , Ratones , Protoporfirinas/química , Protoporfirinas/farmacología , Dinoprostona/metabolismo
5.
J Virol ; 97(11): e0106723, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37855618

RESUMEN

IMPORTANCE: Many plant viruses are transmitted by insect vectors in a circulative manner. For efficient transmission, the entry of the virus from vector hemolymph into the primary salivary gland (PSG) is a step of paramount importance. Yet, vector components mediating virus entry into PSG remain barely characterized. Here, we demonstrate the role of clathrin-mediated endocytosis and early endosomes in begomovirus entry into whitefly PSG. Our findings unravel the key components involved in begomovirus transport within the whitefly body and transmission by their whitefly vectors and provide novel clues for blocking begomovirus transmission.


Asunto(s)
Begomovirus , Endocitosis , Hemípteros , Animales , Begomovirus/fisiología , Clatrina/metabolismo , Endosomas , Hemípteros/metabolismo , Hemípteros/virología , Enfermedades de las Plantas , Glándulas Salivales/metabolismo , Glándulas Salivales/virología
6.
EMBO Rep ; 23(6): e54147, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35373418

RESUMEN

Developmental arsenic exposure has been associated with cognitive deficits in epidemiological studies, but the underlying mechanisms remain poorly understood. Here, we establish a mouse model of developmental arsenic exposure exhibiting deficits of recognition and spatial memory in the offspring. These deficits are associated with genome-wide DNA hypomethylation and abnormal expression of cognition-related genes in the hippocampus. Arsenic atoms directly bind to the cysteine-rich ADD domain of DNA methyltransferase 3A (DNMT3A), triggering ubiquitin- and proteasome-mediated degradation of DNMT3A in different cellular contexts. DNMT3A degradation leads to genome-wide DNA hypomethylation in mouse embryonic fibroblasts but not in non-embryonic cell lines. Treatment with metformin, a first-line antidiabetic agent reported to increase DNA methylation, ameliorates the behavioral deficits and normalizes the aberrant expression of cognition-related genes and DNA methylation in the hippocampus of arsenic-exposed offspring. Our study establishes a DNA hypomethylation effect of developmental arsenic exposure and proposes a potential treatment against cognitive deficits in the offspring of pregnant women in arsenic-contaminated areas.


Asunto(s)
Arsénico , Metilación de ADN , ADN Metiltransferasa 3A , Animales , Arsénico/toxicidad , Cognición , Femenino , Fibroblastos/metabolismo , Humanos , Ratones , Embarazo
7.
J Org Chem ; 89(14): 10393-10402, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-38953569

RESUMEN

α-Quaternary amino acids have found application in many biologically relevant compounds and pharmaceuticals. Although there are many methods for the synthesis of α-quaternary amino acids, most of them are mainly realized with the aid of transition metals and complex ligands. We present herein a 2,7-Br-4CzIPN catalyzed regioselective alkylation of azlactones with redox-active esters via radical-radical couplings. Strikingly, this approach is devoid of any metal or additive and shows broad scope and superior sensitive functional group compatibility.

8.
BMC Gastroenterol ; 24(1): 117, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38515017

RESUMEN

OBJECTIVE: To determine the high-efficiency ancillary features (AFs) screened from LR-3/4 lesions and the HCC/non-HCC group and the diagnostic performance of LR3/4 observations. MATERIALS AND METHODS: We retrospectively analyzed a total of 460 patients (with 473 nodules) classified into LR-3-LR-5 categories, including 311 cases of hepatocellular carcinoma (HCC), 6 cases of non-HCC malignant tumors, and 156 cases of benign lesions. Two faculty abdominal radiologists with experience in hepatic imaging reviewed and recorded the major features (MFs) and AFs of the Liver Imaging Reporting and Data System (LI-RADS). The frequency of the features and diagnostic performance were calculated with a logistic regression model. After applying the above AFs to LR-3/LR-4 observations, the sensitivity and specificity for HCC were compared. RESULTS: The average age of all patients was 54.24 ± 11.32 years, and the biochemical indicators ALT (P = 0.044), TBIL (P = 0.000), PLT (P = 0.004), AFP (P = 0.000) and Child‒Pugh class were significantly higher in the HCC group. MFs, mild-moderate T2 hyperintensity, restricted diffusion and AFs favoring HCC in addition to nodule-in-nodule appearance were common in the HCC group and LR-5 category. AFs screened from the HCC/non-HCC group (AF-HCC) were mild-moderate T2 hyperintensity, restricted diffusion, TP hypointensity, marked T2 hyperintensity and HBP isointensity (P = 0.005, < 0.001, = 0. 032, p < 0.001, = 0.013), and the AFs screened from LR-3/4 lesions (AF-LR) were restricted diffusion, mosaic architecture, fat in mass, marked T2 hyperintensity and HBP isointensity (P < 0.001, = 0.020, = 0.036, < 0.001, = 0.016), which were not exactly the same. After applying AF-HCC and AF-LR to LR-3 and LR-4 observations in HCC group and Non-HCC group, After the above grades changed, the diagnostic sensitivity for HCC were 84.96% using AF-HCC and 85.71% using AF-LR, the specificity were 89.26% using AF-HCC and 90.60% using AF-LR, which made a significant difference (P = 0.000). And the kappa value for the two methods of AF-HCC and AF-LR were 0.695, reaching a substantial agreement. CONCLUSION: When adjusting for LR-3/LR-4 lesions, the screened AFs with high diagnostic ability can be used to optimize LI-RADS v2018; among them, AF-LR is recommended for better diagnostic capabilities.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Adulto , Persona de Mediana Edad , Anciano , Carcinoma Hepatocelular/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Estudios Retrospectivos , Reproducibilidad de los Resultados , Imagen por Resonancia Magnética/métodos , Sensibilidad y Especificidad , Medios de Contraste
9.
Acta Pharmacol Sin ; 45(1): 137-149, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37640899

RESUMEN

Sirtuins (Sirts) are a family of nicotinamide adenine dinucleotide-dependent protein deacetylases that share diverse cellular functions. Increasing evidence shows that Sirts play a critical role in podocyte injury, which is a major determinant of proteinuria-associated renal disease. Membranous nephropathy (MN) is a typical glomerular disease in which podocyte damage mediates proteinuria development. In this study we investigated the molecular mechanisms underlying the regulatory roles of Sirt in podocyte injury in MN patients, rats with cationic bovine serum albumin (CBSA)-induced MN and zymosan activation serum (ZAS)-stimulated podocytes. Compared with healthy controls, MN patients showed significant reduction in intrarenal Sirt1 and Sirt6 protein expression. In CBSA-induced MN rats, significant reduction in intrarenal Sirt1, Sirt3 and Sirt6 protein expression was observed. However, only significant decrease in Sirt6 protein expression was found in ZAS-stimulated podocytes. MN patients showed significantly upregulated protein expression of Wnt1 and ß-catenin and renin-angiotensin system (RAS) components in glomeruli. CBSA-induced MN rats exhibited significantly upregulated protein expression of intrarenal Wnt1 and ß-catenin and their downstream gene products as well as RAS components. Similar results were observed in ZAS-stimulated podocytes. In ZAS-stimulated podocytes, treatment with a specific Sirt6 activator UBCS039 preserved the protein expression of podocin, nephrin and podocalyxin, accompanied by significant inhibition of the protein expression of ß-catenin and its downstream gene products, including Snail1 and Twist; treatment with a ß-catenin inhibitor ICG-001 significantly preserved the expression of podocyte-specific proteins and inhibited the upregulation of downstream ß-catenin gene products accompanied by significant suppression of the protein expression of RAS components. Thus, we demonstrate that Sirt6 ameliorates podocyte injury by blocking RAS signalling via the Wnt1/ß-catenin pathway. Sirt6 is a specific therapeutic target for the treatment of podocyte damage-associated renal disease.


Asunto(s)
Enfermedades Renales , Podocitos , Humanos , Ratas , Animales , beta Catenina/metabolismo , Podocitos/metabolismo , Sirtuina 1/metabolismo , Sistema Renina-Angiotensina , Enfermedades Renales/metabolismo , Proteinuria
10.
Acta Pharmacol Sin ; 45(5): 988-1001, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38279043

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is a common metabolic disease that is substantially associated with obesity-induced chronic inflammation. Macrophage activation and macrophage-medicated inflammation play crucial roles in the development and progression of NAFLD. Furthermore, fibroblast growth factor receptor 1 (FGFR1) has been shown to be essentially involved in macrophage activation. This study investigated the role of FGFR1 in the NAFLD pathogenesis and indicated that a high-fat diet (HFD) increased p-FGFR1 levels in the mouse liver, which is associated with increased macrophage infiltration. In addition, macrophage-specific FGFR1 knockout or administration of FGFR1 inhibitor markedly protected the liver from HFD-induced lipid accumulation, fibrosis, and inflammatory responses. The mechanistic study showed that macrophage-specific FGFR1 knockout alleviated HFD-induced liver inflammation by suppressing the activation of MAPKs and TNF signaling pathways and reduced fat deposition in hepatocytes, thereby inhibiting the activation of hepatic stellate cells. In conclusion, the results of this research revealed that FGFR1 could protect the liver of HFD-fed mice by inhibiting MAPKs/TNF-mediated inflammatory responses in macrophages. Therefore, FGFR1 can be employed as a target to prevent the development and progression of NAFLD.


Asunto(s)
Dieta Alta en Grasa , Macrófagos , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos , Factor de Necrosis Tumoral alfa , Animales , Dieta Alta en Grasa/efectos adversos , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/antagonistas & inhibidores , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Ratones , Masculino , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Enfermedad del Hígado Graso no Alcohólico/etiología , Factor de Necrosis Tumoral alfa/metabolismo , Ratones Noqueados , Hígado/patología , Hígado/metabolismo , Transducción de Señal , Inflamación/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos
11.
Acta Pharmacol Sin ; 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38811775

RESUMEN

Proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to the epidermal growth factor precursor homologous domain A (EGF-A) of low-density lipoprotein receptor (LDLR) in the liver and triggers the degradation of LDLR via the lysosomal pathway, consequently leading to an elevation in plasma LDL-C levels. Inhibiting PCSK9 prolongs the lifespan of LDLR and maintains cholesterol homeostasis in the body. Thus, PCSK9 is an innovative pharmacological target for treating hypercholesterolemia and atherosclerosis. In this study, we discovered that E28362 was a novel small-molecule PCSK9 inhibitor by conducting a virtual screening of a library containing 40,000 compounds. E28362 (5, 10, 20 µM) dose-dependently increased the protein levels of LDLR in both total protein and the membrane fraction in both HepG2 and AML12 cells, and enhanced the uptake of DiI-LDL in AML12 cells. MTT assay showed that E28362 up to 80 µM had no obvious toxicity in HepG2, AML12, and HEK293a cells. The effects of E28362 on hyperlipidemia and atherosclerosis were evaluated in three different animal models. In high-fat diet-fed golden hamsters, administration of E28362 (6.7, 20, 60 mg·kg-1·d-1, i.g.) for 4 weeks significantly reduced plasma total cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C) and PCSK9 levels, and reduced liver TC and TG contents. In Western diet-fed ApoE-/- mice (20, 60 mg·kg-1·d-1, i.g.) and human PCSK9 D374Y overexpression mice (60 mg·kg-1·d-1, i.g.), administration of E28362 for 12 weeks significantly decreased plasma LDL-C levels and the area of atherosclerotic lesions in en face aortas and aortic roots. Moreover, E28362 significantly increased the protein expression level of LDLR in the liver. We revealed that E28362 selectively bound to PCSK9 in HepG2 and AML12 cells, blocked the interaction between LDLR and PCSK9, and induced the degradation of PCSK9 through the ubiquitin-proteasome pathway, which finally resulted in increased LDLR protein levels. In conclusion, E28362 can block the interaction between PCSK9 and LDLR, induce the degradation of PCSK9, increase LDLR protein levels, and alleviate hyperlipidemia and atherosclerosis in three distinct animal models, suggesting that E28362 is a promising lead compound for the treatment of hyperlipidemia and atherosclerosis.

12.
Eur Child Adolesc Psychiatry ; 33(8): 2629-2636, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38170284

RESUMEN

This study aimed to examine the reciprocal relation between body mass index and internalizing behavior from age 2 to 15, and also the predictive role of executive function. This study included a subset sample of 640 children (47% were male) from the National Institute of Child Health and Development Study of Early Child Care and Youth Development. A refined random-intercept cross-lagged model was employed to analyze: (1) the reciprocal relation between children's body mass index and internalizing behavior assessed in eight waves from age 2 to 15; (2) the predictive role of executive functioning in both children's body mass index and internalizing behavior. Trait-level body mass index-to-internalizing behavior association was not found; a significant state-level prediction from body mass index in 5th grade to internalizing behavior in 6th grade was found. Executive function was significantly associated with trait-level body mass index, trait-level internalizing behaviors, and state-level internalizing behaviors. The findings suggest that deficits in children's executive functioning may be a shared risk associated with both high body mass index and internalizing behaviors. From an intervention perspective, this study highlighted the importance of targeting executive function to intervene in children's obesity or internalizing behaviors.


Asunto(s)
Índice de Masa Corporal , Función Ejecutiva , Humanos , Función Ejecutiva/fisiología , Niño , Femenino , Masculino , Adolescente , Preescolar , Conducta Infantil/fisiología , Conducta Infantil/psicología , Estudios Longitudinales
13.
Mol Pain ; 19: 17448069231177634, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37207346

RESUMEN

Chronic pain, along with comorbid psychiatric disorders, is a common problem worldwide. A growing number of studies have focused on non-opioid-based medicines, and billions of funds have been put into digging new analgesic mechanisms. Peripheral inflammation is one of the critical causes of chronic pain, and drugs with anti-inflammatory effects usually alleviate pain hypersensitivity. Sophoridine (SRI), one of the most abundant alkaloids in Chinese herbs, has been proved to exert antitumor, antivirus and anti-inflammation effects. Here, we evaluated the analgesic effect of SRI in an inflammatory pain mouse model induced by complete Freund's adjuvant (CFA) injection. SRI treatment significantly decreased pro-inflammatory factors release after LPS stimuli in microglia. Three days of SRI treatment relieved CFA-induced mechanical hypersensitivity and anxiety-like behavior, and recovered abnormal neuroplasticity in the anterior cingulate cortex of mice. Therefore, SRI may be a candidate compound for the treatment of chronic inflammatory pain and may serve as a structural basis for the development of new drugs.


Asunto(s)
Dolor Crónico , Hiperalgesia , Ratones , Animales , Hiperalgesia/complicaciones , Hiperalgesia/tratamiento farmacológico , Hiperalgesia/inducido químicamente , Adyuvante de Freund/toxicidad , Matrinas , Dolor Crónico/tratamiento farmacológico , Analgésicos/farmacología , Analgésicos/uso terapéutico , Ansiedad/complicaciones , Ansiedad/tratamiento farmacológico
14.
Rev Physiol Biochem Pharmacol ; 179: 139-188, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33479839

RESUMEN

Mas-related G protein-coupled receptor-X2 (MRGPRX2) is known as a novel receptor to activate mast cells (MCs). MRGPRX2 plays a dual role in promoting MC-dependent host defense and immunomodulation and contributing to the pathogenesis of pseudo-allergic drug reactions, pain, itching, and inflammatory diseases. In this article, we discuss the possible signaling pathways of MCs activation mediated by MRGPRX2 and summarize and classify agonists and inhibitors of MRGPRX2 in MCs activation. MRGPRX2 is a low-affinity and low-selectivity receptor, which allows it to interact with a diverse group of ligands. Diverse MRGPRX2 ligands utilize conserved residues in its transmembrane (TM) domains and carboxyl-terminus Ser/Thr residues to undergo ligand binding and G protein coupling. The coupling likely initiates phosphorylation cascades, induces Ca2+ mobilization, and causes degranulation and generation of cytokines and chemokines via MAPK and NF-κB pathways, resulting in MCs activation. Agonists of MRGPRX2 on MCs are divided into peptides (including antimicrobial peptides, neuropeptides, MC degranulating peptides, peptide hormones) and nonpeptides (including FDA-approved drugs). Inhibitors of MRGPRX2 include non-selective GPCR inhibitors, herbal extracts, small-molecule MRGPRX2 antagonists, and DNA aptamer drugs. Screening and classifying MRGPRX2 ligands and summarizing their signaling pathways would improve our understanding of MRGPRX2-mediated physiological and pathological effects on MCs.


Asunto(s)
Mastocitos , Receptores de Neuropéptido , Ligandos , Proteínas del Tejido Nervioso , Receptores Acoplados a Proteínas G
15.
Toxicol Appl Pharmacol ; 470: 116549, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37164296

RESUMEN

Helicobacter pylori (H. pylori) is an obligate microaerobion and does not survive in low oxygen. Sodium sulfite (SS) reacts and consume oxygen in solutions. The present study aimed to investigate the effects of SS on H. pylori. The effects of SS on oxygen concentrations in solutions and on H. pylori in vivo and in vitro were examined, and the mechanisms involved were explored. The results showed that SS decreased the oxygen concentration in water and artificial gastric juice. In Columbia blood agar and special peptone broth, SS concentration-dependently inhibited the proliferation of H. pylori ATCC43504 and Sydney strain-1 in Columbia blood agar or special peptone broth, and dose-dependently decreased the number of H. pylori in Mongolian gerbils and Kunming mouse infection models. The H. pylori was relapsed in 2 weeks withdrawal and the recurrence in the SS group was lower than that in the positive triple drug group. These effects were superior to positive triple drugs. After SS treatments, the cell membrane and cytoplasm structure of H. pylori were disrupted. SS-induced oxygen-free environment initially blocked aerobic respiration, triggered oxidative stress, disturbed energy production. In conclusion, SS consumes oxygen and creates an oxygen-free environment in which H. pylori does not survive. The present study provides a new strategy and perspective for the clinical treatment of H. pylori infectious disease.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Animales , Ratones , Agar , Peptonas , Modelos Animales de Enfermedad , Mucosa Gástrica , Gerbillinae
16.
Nanotechnology ; 34(14)2023 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-36634354

RESUMEN

The graphene-like wrapped Ni@C catalysts were facilely synthesized by a modified sol-gel method. Nickel nitrate and citric acid (CA) were adopted as the raw materials to form sol-gel mixture. Under the circumstances, the additive CA were employed not only as a complexing agent but also as a carbon source. It is found that the calcination temperature and the mole ratios between Ni and CA are the key factors affecting the physical property and the catalytic performance of catalysts in the conversion of nitroarenes into corresponding anilines. The results show that the Ni@C-500(1:1) catalyst exhibited the best performance in the hydrogenation ofo-chloronitrobenzenes (o-CNB) too-chloroanilines (o-CAN). The yield ofo-CAN was achieved at 100% wheno-CNB was completely converted at 40.0 °C under 2.0 MPa H2for 2.0 h. Furthermore, the Ni@C-500(1:1) catalyst could be separated and recovered easily after reaction by an external magnetic field. The investigated results indicate that the Ni@C-500(1:1) catalyst remained higher activity after using twelve times. More importantly, this kind of catalyst is also active for the selective hydrogenation of other nitroarenes into the corresponding anilines. This new synthetic method may pave a way for producing low-cost Ni@C catalysts on a large scale, which is attractive for industrial anilines applications.

17.
BMC Gastroenterol ; 23(1): 285, 2023 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-37592280

RESUMEN

BACKGROUND: Acute-on-chronic liver failure (ACLF) is a syndrome with high 28- and 90-day mortality rates. Magnetic resonance imaging (MRI) has been widely used to diagnose and evaluate liver disease. Our purpose is to determine the value of the imaging features derived from Gd-DTPA-enhanced MRI for predicting the poor outcome of patients with ACLF and develop a clinically practical radiological score. METHODS: This retrospective study comprised 175 ACLF patients who underwent Gd-DTPA-enhanced abdominal MRI from January 2017 to December 2021. The primary end-point was 90-day mortality. Imaging parameters, such as diffuse hyperintense of the liver on T2WI, patchy enhancement of the liver at the arterial phase, uneven enhancement of the liver at the portal vein phase, gallbladder wall edema, periportal edema, ascites, esophageal and gastric varix, umbilical vein patefac, portal vein thrombosis, and splenomegaly were screened. Cox proportional hazard regression models were used to evaluate prognostic factors and develop a prediction model. The accuracy of the model was evaluated by receiver operating characteristic (ROC) curves. RESULTS: During the follow-up period, 31 of the 175 ACLF patients died within 90 days. In the multivariate analysis, three imaging parameters were independently associated with survival: diffuse hyperintense on T2WI (p = 0.007; HR = 3.53 [1.40-8.89]), patchy enhancement at the arterial phase (p = 0.037; HR = 2.45 [1.06-5.69]), moderate ascites (vs. mild) (p = 0.006; HR = 4.12 [1.49-11.36]), and severe ascites (vs. mild) (p = 0.005; HR = 4.29 [1.57-11.71]). A practical radiological score was proposed, based on the presence of diffuse hyperintense (7 points), patchy enhancement (5 points), and ascites (6, 8, and 8 points for mild, moderate, and severe, respectively). Further analysis showed that a cut-off at 14 points was optimum to distinguish high-risk (score > 14) from the low-risk group (score ≤ 14) for 90-day survival and demonstrated a mean area under the ROC curve of 0.774 in ACLF patients. CONCLUSIONS: Gd-DTPA-enhanced MR imaging features can predict poor outcomes in patients with ACLF, based on which we proposed a clinically practical radiological score allowing stratification of the 90-day survival.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada , Enfermedades de la Vesícula Biliar , Humanos , Insuficiencia Hepática Crónica Agudizada/diagnóstico por imagen , Ascitis/diagnóstico por imagen , Ascitis/etiología , Gadolinio DTPA , Estudios Retrospectivos , Imagen por Resonancia Magnética , Pronóstico
18.
Environ Sci Technol ; 57(47): 18888-18897, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-37387610

RESUMEN

Heterogeneous catalytic ozonation (HCO) is an effective technology for advanced wastewater treatment, while the influence of coexisting salts remains unclear and controversial. Here, we systematically explored the influence of NaCl salinity on the reaction and mass transfer of HCO through lab experiments, kinetic simulation, and computational fluid dynamics modeling, and proposed that the trade-off between reaction inhibition and mass transfer enhancement would affect the pollutants degradation pattern under varying salinity. The increase of NaCl salinity decreased ozone solubility and accelerated the futile consumption of ozone and hydroxyl radicals (•OH), and the maximum •OH concentration under 50 g/L salinity was only 23% of that without salinity. However, the increase of NaCl salinity also significantly reduced the ozone bubble size and enhanced the interphase and intraliquid mass transfer, with the volumetric mass transfer coefficient being 130% higher than that without salinity. The trade-off between reaction inhibition and mass transfer enhancement shifted under different pH values and aerator pore sizes, and the oxalate degradation pattern would change correspondingly. Besides, the trade-off was also identified for Na2SO4 salinity. These results emphasized the dual influence of salinity and offered a new theoretical perspective on the role of salinity in the HCO process.


Asunto(s)
Ozono , Contaminantes Químicos del Agua , Purificación del Agua , Cloruro de Sodio , Salinidad , Radical Hidroxilo , Sales (Química) , Catálisis , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos
19.
Pacing Clin Electrophysiol ; 46(12): 1635-1642, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37942981

RESUMEN

OBJECTIVE: This study aimed to explore the roles of duration and burden of atrial high-rate episode (AHRE) on ischemic stroke in patients with pacemaker implantation. METHODS: Patients with pacemaker implantation for bradycardia from 2013 to 2017 were consecutively enrolled. Data such as gender, age, combined diseases, type of AF, left atrial size, left ventricular size, left ventricular ejection fraction, CHA2 DS2 -VASc score, and anticoagulants were collected. The burden and duration of AHRE based on different interval partition were also recorded in detail to evaluate the impacts on ischemic stroke. Cox regression analysis with time-dependent covariates was conducted. RESULTS: A total of 220 patients with AHRE were enrolled. The average follow-up time was 48.42 ± 17.20 months. Univariate regression analysis showed that diabetes (p = .024), high CHA2 DS2 -VASc score (≥ 2) (p = .021), long mean AHRE burden (p = .011), long maximal AHRE burden (p = .015), long AHRE duration lasting≥48 h (p = .001) or 24 h (p = .001) or 12 h (p = .005) were prone to ischemic stroke. Further multivariate regression analysis showed that long duration of AHRE (≥48 h) (HR 10.77; 95% CI 3.22-55.12; p = .030) were significantly correlated with stroke in patients with paroxysmal AF. There was no significant correlation between the type of AF and stroke (p = .927). CONCLUSION: The longer duration of AHRE (≥48 h) was more favorable in predicting ischemic stroke than high CHA2 DS2 -VASc score (≥2).


Asunto(s)
Fibrilación Atrial , Accidente Cerebrovascular Isquémico , Humanos , Medición de Riesgo , Factores de Riesgo , Volumen Sistólico , Función Ventricular Izquierda
20.
Pacing Clin Electrophysiol ; 46(7): 684-692, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37345321

RESUMEN

OBJECTIVE: To identify the predictors of pacing-induced cardiomyopathy (PICM) and illustrate the safety and feasibility of conduction system pacing (CSP) upgrade on patients with long-term persistent atrial fibrillation (AF). METHODS: All patients with long-term persistent AF and normal left ventricular ejection fraction (LVEF) ≥50% were consecutively enrolled from January 2008 to December 2017, and all the patients with atrioventricular block (AVB) and high right ventricular pacing (RVP) percentage of at least 40%. The predictors of PICM were identified, and patients with PICM were followed up for at least 1 year regardless of CSP upgrade. Cardiac performances and lead outcomes were investigated in all patients before and after CSP upgrade. RESULTS: The present study included 139 patients, out of which 37 (26.62%) developed PICM, resulting in a significant decrease in the left ventricular ejection fraction (LVEF) from 56.11 ± 2.56% to 38.10 ± 5.81% (p< .01). The median duration for the development of PICM was 5.43 years. Lower LVEF (≤52.50%), longer paced QRS duration (≥175 ms), and higher RVP percentage (≥96.80%) were identified as independent predictors of PICM. Furthermore, the morbidity of PICM progressively increased with an increased number of predictors. The paced QRS duration (183.90 ± 22.34 ms vs. 136.57 ± 20.71 ms, p < .01), LVEF (39.35 ± 2.71% vs. 47.50 ± 7.43%, p < .01), and left ventricular end-diastolic diameter (LVEDD) (55.53 ± 5.67 mm vs. 53.20 ± 5.78 mm, p = .03) improved significantly on patients accepting CSP upgrade. CSP responses and complete reverse remodeling (LVEF ≥50% and LVEDD < 50 mm) were detected in 80.95% (17/21) and 42.9% (9/21) of patients. The pacing threshold (1.52 ± 0.78 V/0.4 ms vs. 1.27 ± 0.59 V/0.4 ms, p = .16) was stable after follow-up. CONCLUSION: PICM is very common in patients with long-term persistent AF, and CSP upgrade was favorable for better cardiac performance in this patient population.


Asunto(s)
Fibrilación Atrial , Cardiomiopatías , Humanos , Fibrilación Atrial/terapia , Volumen Sistólico/fisiología , Función Ventricular Izquierda/fisiología , Trastorno del Sistema de Conducción Cardíaco/terapia , Estimulación Cardíaca Artificial/métodos
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