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1.
Cell ; 184(7): 1693-1705.e17, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33770502

RESUMEN

Plants protect themselves with a vast array of toxic secondary metabolites, yet most plants serve as food for insects. The evolutionary processes that allow herbivorous insects to resist plant defenses remain largely unknown. The whitefly Bemisia tabaci is a cosmopolitan, highly polyphagous agricultural pest that vectors several serious plant pathogenic viruses and is an excellent model to probe the molecular mechanisms involved in overcoming plant defenses. Here, we show that, through an exceptional horizontal gene transfer event, the whitefly has acquired the plant-derived phenolic glucoside malonyltransferase gene BtPMaT1. This gene enables whiteflies to neutralize phenolic glucosides. This was confirmed by genetically transforming tomato plants to produce small interfering RNAs that silence BtPMaT1, thus impairing the whiteflies' detoxification ability. These findings reveal an evolutionary scenario whereby herbivores harness the genetic toolkit of their host plants to develop resistance to plant defenses and how this can be exploited for crop protection.


Asunto(s)
Hemípteros/genética , Proteínas de Insectos/metabolismo , Solanum lycopersicum/genética , Toxinas Biológicas/metabolismo , Animales , Transferencia de Gen Horizontal , Genes de Plantas , Glucósidos/química , Glucósidos/metabolismo , Hemípteros/fisiología , Herbivoria , Proteínas de Insectos/antagonistas & inhibidores , Proteínas de Insectos/clasificación , Proteínas de Insectos/genética , Mucosa Intestinal/metabolismo , Solanum lycopersicum/metabolismo , Malonil Coenzima A/metabolismo , Filogenia , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Interferencia de ARN , ARN Bicatenario/metabolismo , Toxinas Biológicas/química
3.
PLoS Genet ; 20(2): e1011163, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38377137

RESUMEN

Neonicotinoid insecticides, which target insect nicotinic acetylcholine receptors (nAChRs), have been widely and intensively used to control the whitefly, Bemisia tabaci, a highly damaging, globally distributed, crop pest. This has inevitably led to the emergence of populations with resistance to neonicotinoids. However, to date, there have been no reports of target-site resistance involving mutation of B. tabaci nAChR genes. Here we characterize the nAChR subunit gene family of B. tabaci and identify dual mutations (A58T&R79E) in one of these genes (BTß1) that confer resistance to multiple neonicotinoids. Transgenic D. melanogaster, where the native nAChR Dß1 was replaced with BTß1A58T&R79E, were significantly more resistant to neonicotinoids than flies where Dß1 were replaced with the wildtype BTß1 sequence, demonstrating the causal role of the mutations in resistance. The two mutations identified in this study replace two amino acids that are highly conserved in >200 insect species. Three-dimensional modelling suggests a molecular mechanism for this resistance, whereby A58T forms a hydrogen bond with the R79E side chain, which positions its negatively-charged carboxylate group to electrostatically repulse a neonicotinoid at the orthosteric site. Together these findings describe the first case of target-site resistance to neonicotinoids in B. tabaci and provide insight into the molecular determinants of neonicotinoid binding and selectivity.


Asunto(s)
Hemípteros , Insecticidas , Receptores Nicotínicos , Animales , Receptores Nicotínicos/genética , Insecticidas/farmacología , Hemípteros/genética , Drosophila melanogaster , Neonicotinoides/farmacología , Mutación
4.
Proc Natl Acad Sci U S A ; 120(48): e2312848120, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-37983512

RESUMEN

The availability of natural protein sequences synergized with generative AI provides new paradigms to engineer enzymes. Although active enzyme variants with numerous mutations have been designed using generative models, their performance often falls short of their wild type counterparts. Additionally, in practical applications, choosing fewer mutations that can rival the efficacy of extensive sequence alterations is usually more advantageous. Pinpointing beneficial single mutations continues to be a formidable task. In this study, using the generative maximum entropy model to analyze Renilla luciferase (RLuc) homologs, and in conjunction with biochemistry experiments, we demonstrated that natural evolutionary information could be used to predictively improve enzyme activity and stability by engineering the active center and protein scaffold, respectively. The success rate to improve either luciferase activity or stability of designed single mutants is ~50%. This finding highlights nature's ingenious approach to evolving proficient enzymes, wherein diverse evolutionary pressures are preferentially applied to distinct regions of the enzyme, ultimately culminating in an overall high performance. We also reveal an evolutionary preference in RLuc toward emitting blue light that holds advantages in terms of water penetration compared to other light spectra. Taken together, our approach facilitates navigation through enzyme sequence space and offers effective strategies for computer-aided rational enzyme engineering.


Asunto(s)
Luz , Mutación , Luciferasas de Renilla/genética , Luciferasas de Renilla/metabolismo , Estabilidad de Enzimas
5.
Proc Natl Acad Sci U S A ; 120(14): e2300439120, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-36996102

RESUMEN

Ongoing host-pathogen interactions can trigger a coevolutionary arms race, while genetic diversity within the host can facilitate its adaptation to pathogens. Here, we used the diamondback moth (Plutella xylostella) and its pathogen Bacillus thuringiensis (Bt) as a model for exploring an adaptive evolutionary mechanism. We found that insect host adaptation to the primary Bt virulence factors was tightly associated with a short interspersed nuclear element (SINE - named SE2) insertion into the promoter of the transcriptionally activated MAP4K4 gene. This retrotransposon insertion coopts and potentiates the effect of the transcription factor forkhead box O (FOXO) in inducing a hormone-modulated Mitogen-activated protein kinase (MAPK) signaling cascade, leading to an enhancement of a host defense mechanism against the pathogen. This work demonstrates that reconstructing a cis-trans interaction can escalate a host response mechanism into a more stringent resistance phenotype to resist pathogen infection, providing a new insight into the coevolutionary mechanism of host organisms and their microbial pathogens.


Asunto(s)
Bacillus thuringiensis , Mariposas Nocturnas , Animales , Endotoxinas/farmacología , Retroelementos/genética , Mariposas Nocturnas/metabolismo , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis/metabolismo , Resistencia a los Insecticidas/genética , Larva/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Hemolisinas/metabolismo
6.
Stem Cells ; 42(6): 540-553, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38393342

RESUMEN

Exploring the mechanism of self-renewal and pluripotency maintenance of human embryonic stem cells (hESCs) is of great significance in basic research and clinical applications, but it has not been fully elucidated. Long non-coding RNAs (lncRNAs) have been shown to play a key role in the self-renewal and pluripotency maintenance of hESCs. We previously reported that the lncRNA ESRG, which is highly expressed in undifferentiated hESCs, can maintain the self-renewal and pluripotency of hPSCs. RNA pull-down mass spectrometry showed that ESRG could bind to other proteins, among which heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) attracted our attention. In this study, we showed that HNRNPA1 can maintain self-renewal and pluripotency of hESCs. ESRG bound to and stabilized HNRNPA1 protein through the ubiquitin-proteasome pathway. In addition, knockdown of ESRG or HNRNPA1 resulted in alternative splicing of TCF3, which originally and primarily encoded E12, to mainly encode E47 and inhibit CDH1 expression. HNRNPA1 could rescue the biological function changes of hESCs caused by ESRG knockdown or overexpression. Our results suggest that ESRG regulates the alternative splicing of TCF3 to affect CDH1 expression and maintain hESCs self-renewal and pluripotency by binding and stabilizing HNRNPA1 protein. This study lays a good foundation for exploring the new molecular regulatory mechanism by which ESRG maintains hESCs self-renewal and pluripotency.


Asunto(s)
Empalme Alternativo , Ribonucleoproteína Nuclear Heterogénea A1 , Células Madre Embrionarias Humanas , ARN Largo no Codificante , Humanos , Empalme Alternativo/genética , Células Madre Embrionarias Humanas/metabolismo , Células Madre Embrionarias Humanas/citología , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Ribonucleoproteína Nuclear Heterogénea A1/metabolismo , Ribonucleoproteína Nuclear Heterogénea A1/genética , Autorrenovación de las Células/genética , Células Madre Pluripotentes/metabolismo , Células Madre Pluripotentes/citología , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/genética , Diferenciación Celular/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética
7.
FASEB J ; 38(8): e23613, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38661048

RESUMEN

The unpredictable survival rate of autologous fat grafting (AFG) seriously affects its clinical application. Improving the survival rate of AFG has become an unresolved issue in plastic surgery. Peroxisome proliferator-activated receptor-γ (PPAR-γ) regulates the adipogenic differentiation of adipocytes, but the functional mechanism in AFG remains unclear. In this study, we established an animal model of AFG and demonstrated the superior therapeutic effect of PPAR-γ regulation in the process of AFG. From day 3 after fat grafting, the PPAR-γ agonist rosiglitazone group consistently showed better adipose integrity, fewer oil cysts, and fibrosis. Massive macrophage infiltration was observed after 7 days. At the same time, M2 macrophages begin to appear. At day 14, M2 macrophages gradually became the dominant cell population, which suppressed inflammation and promoted revascularization and fat regeneration. In addition, transcriptome sequencing showed that the differentially expressed genes in the Rosiglitazone group were associated with the pathways of adipose regeneration, differentiation, and angiogenesis; these results provide new ideas for clinical treatment.


Asunto(s)
Tejido Adiposo , Macrófagos , PPAR gamma , Rosiglitazona , Trasplante Autólogo , Animales , PPAR gamma/metabolismo , PPAR gamma/genética , Macrófagos/metabolismo , Tejido Adiposo/metabolismo , Tejido Adiposo/citología , Rosiglitazona/farmacología , Masculino , Diferenciación Celular , Adipogénesis , Adipocitos/metabolismo , Ratones , Ratas
8.
Proc Natl Acad Sci U S A ; 119(31): e2207904119, 2022 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-35901204

RESUMEN

Laboratory evolution combined with computational enzyme design provides the opportunity to generate novel biocatalysts. Nevertheless, it has been challenging to understand how laboratory evolution optimizes designer enzymes by introducing seemingly random mutations. A typical enzyme optimized with laboratory evolution is the abiological Kemp eliminase, initially designed by grafting active site residues into a natural protein scaffold. Here, we relate the catalytic power of laboratory-evolved Kemp eliminases to the statistical energy ([Formula: see text]) inferred from their natural homologous sequences using the maximum entropy model. The [Formula: see text] of designs generated by directed evolution is correlated with enhanced activity and reduced stability, thus displaying a stability-activity trade-off. In contrast, the [Formula: see text] for mutants in catalytic-active remote regions (in which remote residues are important for catalysis) is strongly anticorrelated with the activity. These findings provide an insight into the role of protein scaffolds in the adaption to new enzymatic functions. It also indicates that the valley in the [Formula: see text] landscape can guide enzyme design for abiological catalysis. Overall, the connection between laboratory and natural evolution contributes to understanding what is optimized in the laboratory and how new enzymatic function emerges in nature, and provides guidance for computational enzyme design.


Asunto(s)
Evolución Molecular Dirigida , Enzimas , Ingeniería de Proteínas , Catálisis , Dominio Catalítico , Entropía , Enzimas/metabolismo , Mutación
9.
Proc Natl Acad Sci U S A ; 119(7)2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35135886

RESUMEN

Although computational enzyme design is of great importance, the advances utilizing physics-based approaches have been slow, and further progress is urgently needed. One promising direction is using machine learning, but such strategies have not been established as effective tools for predicting the catalytic power of enzymes. Here, we show that the statistical energy inferred from homologous sequences with the maximum entropy (MaxEnt) principle significantly correlates with enzyme catalysis and stability at the active site region and the more distant region, respectively. This finding decodes enzyme architecture and offers a connection between enzyme evolution and the physical chemistry of enzyme catalysis, and it deepens our understanding of the stability-activity trade-off hypothesis for enzymes. Overall, the strong correlations found here provide a powerful way of guiding enzyme design.

10.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35115408

RESUMEN

A variety of signals, including inflammasome activation, trigger the formation of large transmembrane pores by gasdermin D (GSDMD). There are primarily two functions of the GSDMD pore, to drive lytic cell death, known as pyroptosis, and to permit the release of leaderless interleukin-1 (IL-1) family cytokines, a process that does not require pyroptosis. We are interested in the mechanism by which the GSDMD pore channels IL-1 release from living cells. Recent studies revealed that electrostatic interaction, in addition to cargo size, plays a critical role in GSDMD-dependent protein release. Here, we determined computationally that to enable electrostatic filtering against pro-IL-1ß, acidic lipids in the membrane need to effectively neutralize positive charges in the membrane-facing patches of the GSDMD pore. In addition, we predicted that salt has an attenuating effect on electrostatic filtering and then validated this prediction using a liposome leakage assay. A calibrated electrostatic screening factor is necessary to account for the experimental observations, suggesting that ion distribution within the pore may be different from the bulk solution. Our findings corroborate the electrostatic influence of IL-1 transport exerted by the GSDMD pore and reveal extrinsic factors, including lipid and salt, that affect the electrostatic environment.


Asunto(s)
Interleucina-1/metabolismo , Proteínas de Unión a Fosfato/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Animales , Membrana Celular/metabolismo , Humanos , Inflamasomas/metabolismo , Ratones , Piroptosis/fisiología , Electricidad Estática
11.
J Biol Chem ; 299(3): 103026, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36796516

RESUMEN

Autoimmune hepatitis (AIH) is a typical T cell-mediated chronic liver disease with a higher incidence in females. However, the molecular mechanism for the female predisposition is poorly understood. Estrogen sulfotransferase (Est) is a conjugating enzyme best known for its function in sulfonating and deactivating estrogens. The goal of this study is to investigate whether and how Est plays a role in the higher incidence of AIH in females. Concanavalin A (ConA) was used to induce T cell-mediated hepatitis in female mice. We first showed that Est was highly induced in the liver of ConA-treated mice. Systemic or hepatocyte-specific ablation of Est, or pharmacological inhibition of Est, protected female mice from ConA-induced hepatitis regardless of ovariectomy, suggesting the effect of Est inhibition was estrogen independent. In contrast, we found that hepatocyte-specific transgenic reconstitution of Est in the whole-body Est knockout (EstKO) mice abolished the protective phenotype. Upon the ConA challenge, EstKO mice exhibited a more robust inflammatory response with elevated production of proinflammatory cytokines and changed liver infiltration of immune cells. Mechanistically, we determined that ablation of Est led to the hepatic induction of lipocalin 2 (Lcn2), whereas ablation of Lcn2 abolished the protective phenotype of EstKO females. Our findings demonstrate that hepatocyte Est is required for the sensitivity of female mice to ConA-induced and T cell-mediated hepatitis in an estrogen-independent manner. Est ablation may have protected female mice from ConA-induced hepatitis by upregulating Lcn2. Pharmacological inhibition of Est might be a potential strategy for the treatment of AIH.


Asunto(s)
Estrógenos , Hepatitis Autoinmune , Ratones , Femenino , Animales , Concanavalina A/toxicidad , Estrógenos/farmacología , Linfocitos T , Hepatocitos , Hígado , Hepatitis Autoinmune/genética , Hepatitis Autoinmune/prevención & control , Ratones Noqueados , Ratones Endogámicos C57BL
12.
J Am Chem Soc ; 146(20): 13875-13885, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38718165

RESUMEN

Bioluminescence is a fascinating natural phenomenon, wherein organisms produce light through specific biochemical reactions. Among these organisms, Renilla luciferase (RLuc) derived from the sea pansy Renilla reniformis is notable for its blue light emission and has potential applications in bioluminescent tagging. Our study focuses on RLuc8, a variant of RLuc with eight amino acid substitutions. Recent studies have shown that the luminescent emitter coelenteramide can adopt multiple protonation states, which may be influenced by nearby residues at the enzyme's active site, demonstrating a complex interplay between protein structure and bioluminescence. Herein, using the quantum mechanical consistent force field method and the semimacroscopic protein dipole-Langevin dipole method with linear response approximation, we show that the phenolate state of coelenteramide in RLuc8 is the primary light-emitting species in agreement with experimental results. Our calculations also suggest that the proton transfer (PT) from neutral coelenteramide to Asp162 plays a crucial role in the bioluminescence process. Additionally, we reproduced the observed emission maximum for the amide anion in RLuc8-D120A and the pyrazine anion in the presence of a Na+ counterion in RLuc8-D162A, suggesting that these are the primary emitters. Furthermore, our calculations on the neutral emitter in the engineered AncFT-D160A enzyme, structurally akin to RLuc8-D162A but with a considerably blue-shifted emission peak, aligned with the observed data, possibly explaining the variance in emission peaks. Overall, this study demonstrates an effective approach to investigate chromophores' bimolecular states while incorporating the PT process in emission spectra calculations, contributing valuable insights for future studies of PT in photoproteins.


Asunto(s)
Pirazinas , Teoría Cuántica , Pirazinas/química , Pirazinas/metabolismo , Renilla/enzimología , Luciferasas/química , Luciferasas/metabolismo , Luminiscencia , Animales , Imidazoles/química , Bencenoacetamidas
13.
Am J Gastroenterol ; 119(4): 700-711, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37929952

RESUMEN

INTRODUCTION: Portal hypertension progression can be relieved after controlling the etiology of liver cirrhosis. Whether beta-blockers could additionally enhance the effects during treatment, particularly for small esophageal varices (EV), was unclear. This study aims to assess the efficacy of add-on carvedilol to delay EV progression during anti-hepatitis B virus (HBV) treatment in HBV-related cirrhosis. METHODS: This randomized controlled trial enrolled patients with virologically suppressed HBV-compensated cirrhosis and small/medium EV. The participants were randomly assigned to receive nucleos(t)ide analog (NUC) or carvedilol 12.5 mg plus NUC (1:1 allocation ratio). The primary end point was the progression rate of EV at 2 years of follow-up. RESULTS: A total of 238 patients (small EV, 77.3%) were randomized into 119 NUC and 119 carvedilol plus NUC (carvedilol [CARV] combination group). Among them, 205 patients (86.1%) completed paired endoscopies. EV progression rate was 15.5% (16/103) in the NUC group and 12.7% (13/102) in the CARV combination group (relative risk = 0.79, 95% confidence interval 0.36-1.75, P = 0.567). Subgroup analysis on medium EV showed the CARV combination group had a more favorable effect in promoting EV regression (43.5% vs 13.1%, P = 0.022) than NUC alone, but not in small cases ( P = 0.534). The incidence of liver-related events (decompensation, hepatocellular carcinoma, or death/liver transplantation) within 2 years was similar between the 2 groups (11.2% vs 10.4%, P = 0.881). DISCUSSION: The overall results did not show statistically significant differences between the added carvedilol strategy and NUC monotherapy in preventing EV progression in patients with virologically suppressed HBV-compensated cirrhosis. However, the carvedilol-added approach might offer improved outcomes specifically for patients with medium EV (NCT03736265).


Asunto(s)
Virus de la Hepatitis B , Neoplasias Hepáticas , Humanos , Carvedilol/uso terapéutico , Antivirales/uso terapéutico , Cirrosis Hepática/tratamiento farmacológico
14.
J Autoimmun ; 147: 103264, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38843578

RESUMEN

BACKGROUND & AIMS: Epidemiology of primary sclerosing cholangitis (PSC) is lacking in China. We aimed to estimate the period prevalence and depict the clinical features of PSC in China. METHODS: We identified and included PSC cases between 2000 and 2023 from two sources: electronic medical records (EMR) and systematical literature retrieval (SLR). The period prevalence of PSC was estimated by the multiplier method. Rate ratios (RRs) for PSC prevalence in relation to macroeconomic indicators were calculated by the negative binomial regression model. RESULTS: A total of 1358 PSC cases were retrieved from 299 hospitals (162 from EMR and 1196 from SLR). Males accounted for 55.7 % of the PSC cases and 25.7 % had concomitant inflammatory bowel disease (IBD). The estimated period prevalence of PSC from 2000 to 2023 was 2.36 (95 % CI: 1.82, 3.34) per 100,000. Males had a numerically higher PSC prevalence than females (2.56, 95 % CI: 1.97, 3.63 vs. 2.14, 95 % CI: 1.65, 3.04 per 100,000). The highest prevalence of PSC was in East China at 4.87 (95 % CI: 3.44, 7.18) per 100,000, followed by North China at 2.94 (95 % CI: 2.33, 3.74) per 100,000, and the lowest in South China at 0.92 (95 % CI: 0.66, 1.30) per 100,000. Regional per capita GDP (RR 1.65, 95 % CI: 1.03, 2.65) and healthcare expenditure (RR 1.94, 95 % CI: 1.13, 3.38) were identified to be associated with PSC prevalence. CONCLUSION: Our study showed the estimated PSC prevalence varied within China, but was generally lower than that in Western countries.


Asunto(s)
Colangitis Esclerosante , Registros Electrónicos de Salud , Humanos , Colangitis Esclerosante/epidemiología , China/epidemiología , Prevalencia , Masculino , Femenino , Persona de Mediana Edad , Adulto , Adolescente , Anciano , Enfermedades Inflamatorias del Intestino/epidemiología , Adulto Joven , Niño
15.
BMC Cancer ; 24(1): 141, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287304

RESUMEN

Gastric cancer (GC) remains a predominant form of malignant tumor globally, necessitating innovative non-surgical therapeutic approaches. This investigation aimed to delineate the expression landscape of macrophage-associated genes in GC and to evaluate their prognostic significance and influence on immunotherapeutic responsiveness. Utilizing the CellMarker2.0 database, we identified 69 immune cell markers with prognostic relevance in GC, including 12 macrophage-specific genes. A Weighted Gene Co-Expression Network Analysis (WGCNA) isolated 3,181 genes correlated with these macrophage markers. The Cancer Genome Atlas (TCGA-STAD) dataset was employed as the training set, while data from the GSE62254 served as the validation cohort. 13 genes were shortlisted through LASSO-Cox regression to formulate a prognostic model. Multivariable Cox regression substantiated that the calculated risk score serves as an imperative independent predictor of overall survival (OS). Distinct macrophage infiltration profiles, pathway associations, treatment susceptibilities, and drug sensitivities were observed between high- and low-risk groups. The preliminary validation of ANXA5 in predicting the survival rates of GC patients at 1 year, 3 years, and 5 years, as well as its expression levels were higher and role in promoting tumor angiogenesis in GC through immunohistochemistry and angiogenesis experiments. In summary, macrophage-related genes were potentially a novel crosstalk mechanism between macrophages and endothelial cells in the tumor microenvironment, and the interplay between inflammation and angiogenesis might have also offered new therapeutic targets, providing a new avenue for personalized treatment interventions.


Asunto(s)
Neoplasias Gástricas , Humanos , Pronóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Angiogénesis , Células Endoteliales , Inmunoterapia , Anexina A5 , Microambiente Tumoral/genética
16.
Langmuir ; 40(19): 9965-9974, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38684004

RESUMEN

We present a study on the electrocatalysis of 214-type perovskite oxides LnSrCoO4 (Ln = La, Pr, Sm, Eu, and Ga) with semiconducting-like behavior synthesized using the sol-gel method. Among these five catalysts, PrSrCoO4 exhibits the optimal electrochemical performance in both the oxygen evolution reaction and the hydrogen evolution reaction, mainly due to its larger electrical conductivity, mass activity, and turnover frequency. Importantly, the weak dependency of LSV curves in a KOH solution with different pH values, revealing the adsorbate evolving mechanism in PrSrCoO4, and the density functional theory (DFT) calculations indicate that PrSrCoO4 has a smaller Gibbs free energy and a higher density of states near the Fermi level, which accelerates the electrochemical water splitting. The mutual substitution of different rare-earth elements will change the unit-cell parameters, regulate the electronic states of catalytic active site Co ions, and further affect their catalytic performance. Furthermore, the magnetic results indicate strong spin-orbit coupling in the electroactive sites of Co ions in SmSrCoO4 and EuSrCoO4, whereas the magnetic moments of Co ions in the other three catalysts mainly arise from the spin itself. Our experimental results expand the electrochemical applications of 214-type perovskite oxides and provide a good platform for a deeper understanding of their catalytic mechanisms.

17.
Diabetes Obes Metab ; 26(6): 2456-2465, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38560765

RESUMEN

AIM: We aimed to assess the global implications of low physical activity (LPA) on type 2 diabetes mellitus (T2DM) by utilizing data from the Global Burden of Disease (GBD) 2019. METHODS: The analysis was conducted by examining the age-standardized disability-adjusted life years (DALYs) rates over a 30-year period. To assess the trends, we utilized estimated annual percentage changes (EAPCs). RESULTS: The study revealed a notable increase in the burden of DALYs attributable to T2DM resulting from LPA, with an EAPC of 0.84 (95% confidence interval 0.78-0.89). Among the regions examined, Oceania showed the highest burden, whereas Eastern Europe exhibited the lowest burden. Specifically, within the Central Asia region, a considerable increase in T2DM-LPA DALYs was observed, with an EAPC of 3.18 (95% confidence interval 3.01-3.36). The burden associated with T2DM-LPA DALYs was found to be similar between genders and increased across all age groups, peaking in the 80-84 years. Furthermore, there was a clear association between the socio-demographic index (SDI) and the age-standardized DALYs rate. Regions categorized as low-middle and middle SDI experienced a substantial rise in burden. CONCLUSION: This study highlights a substantial increase in the T2DM-LPA DALYs in low-middle and middle SDI regions, as well as among individuals aged 80-84 years. These findings emphasize the importance of implementing comprehensive global health interventions that promote physical activity, particularly targeting high-risk populations and regions.


Asunto(s)
Diabetes Mellitus Tipo 2 , Ejercicio Físico , Carga Global de Enfermedades , Salud Global , Humanos , Diabetes Mellitus Tipo 2/epidemiología , Masculino , Femenino , Anciano , Persona de Mediana Edad , Anciano de 80 o más Años , Adulto , Años de Vida Ajustados por Discapacidad , Conducta Sedentaria , Adulto Joven , Oceanía/epidemiología
18.
BMC Cardiovasc Disord ; 24(1): 233, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38689231

RESUMEN

OBJECTIVE: This study aimed to examine the changes in absolute value and decline rate of early serum cardiac troponin T (cTnT) and N-terminal pro b-type natriuretic peptide (NT-proBNP) in neonates who received veno-arterial (V-A) extracorporeal membrane oxygenation (ECMO) support therapy within the first week of life. METHODS: We retrospectively collected clinical data and laboratory test results of 18 neonates who underwent V-A ECMO support within one week of birth, from July 2021 to June 2023, using the electronic medical record system. These patients were categorized into survival and death groups. Comparative analyses of the absolute values and decline rates of cTnT and NT-proBNP were made between the groups at baseline, and at 24, 48, and 72 h post-ECMO initiation. RESULTS: Out of the 18 neonates, 12 survived (survival rate: 66.7%), while 6 succumbed. The survival group exhibited significantly lower absolute values of cTnT and NT-proBNP than the death group, and their decline rates were significantly higher. Notably, all neonates without an early decline in cTnT and NT-proBNP levels were in the death group. CONCLUSION: The early changes in the absolute value and decline rate of serum cTnT and NT-proBNP in neonates undergoing V-A ECMO may serve as predictors of their prognosis.


Asunto(s)
Biomarcadores , Oxigenación por Membrana Extracorpórea , Péptido Natriurético Encefálico , Fragmentos de Péptidos , Troponina T , Humanos , Oxigenación por Membrana Extracorpórea/efectos adversos , Oxigenación por Membrana Extracorpórea/mortalidad , Péptido Natriurético Encefálico/sangre , Troponina T/sangre , Recién Nacido , Fragmentos de Péptidos/sangre , Estudios Retrospectivos , Masculino , Femenino , Biomarcadores/sangre , Factores de Tiempo , Resultado del Tratamiento , Valor Predictivo de las Pruebas , Factores de Riesgo
19.
Nature ; 563(7729): E18, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30135587

RESUMEN

In this Letter, the links to Supplementary Videos 5, 7, 9 and 10 were incorrect, and there were some formatting errors in the Supplementary Video legends. These errors have been corrected online.

20.
Nature ; 557(7707): 701-705, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29760468

RESUMEN

Ion hydration and transport at interfaces are relevant to a wide range of applied fields and natural processes1-5. Interfacial effects are particularly profound in confined geometries such as nanometre-sized channels6-8, where the mechanisms of ion transport in bulk solutions may not apply9,10. To correlate atomic structure with the transport properties of hydrated ions, both the interfacial inhomogeneity and the complex competing interactions among ions, water and surfaces require detailed molecular-level characterization. Here we constructed individual sodium ion (Na+) hydrates on a NaCl(001) surface by progressively attaching single water molecules (one to five) to the Na+ ion using a combined scanning tunnelling microscopy and noncontact atomic force microscopy system. We found that the Na+ ion hydrated with three water molecules diffuses orders of magnitude more quickly than other ion hydrates. Ab initio calculations revealed that such high ion mobility arises from the existence of a metastable state, in which the three water molecules around the Na+ ion can rotate collectively with a rather small energy barrier. This scenario would apply even at room temperature according to our classical molecular dynamics simulations. Our work suggests that anomalously high diffusion rates for specific hydration numbers of ions are generally determined by the degree of symmetry match between the hydrates and the surface lattice.

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