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1.
Mol Cancer ; 23(1): 79, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38658974

RESUMEN

R-loops are prevalent three-stranded nucleic acid structures, comprising a DNA-RNA hybrid and a displaced single-stranded DNA, that frequently form during transcription and may be attributed to genomic stability and gene expression regulation. It was recently discovered that RNA modification contributes to maintain the stability of R-loops such as N6-methyladenosine (m6A). Yet, m6A-modified R-loops in regulating gene transcription remains poorly understood. Here, we demonstrated that insulin-like growth factor 2 mRNA-binding proteins (IGF2BPs) recognize R-loops in an m6A-dependent way. Consequently, IGF2BPs overexpression leads to increased overall R-loop levels, cell migration inhibition, and cell growth retardation in prostate cancer (PCa) via precluding the binding of DNA methyltransferase 1(DNMT1) to semaphorin 3 F (SEMA3F) promoters. Moreover, the K homology (KH) domains of IGF2BPs are required for their recognition of m6A-containing R-loops and are required for tumor suppressor functions. Overexpression of SEMA3F markedly enhanced docetaxel chemosensitivity in prostate cancer via regulating Hippo pathway. Our findings point to a distinct R-loop resolution pathway mediated by IGF2BPs, emphasizing the functional importance of IGF2BPs as epigenetic R-loop readers in transcriptional genetic regulation and cancer biology.The manuscript summarizes the new role of N6-methyladenosine in epigenetic regulation, we introduce the distinct R-loop resolution mediated by IGF2BP proteins in an m6A-dependent way, which probably lead to the growth retardation and docetaxel chemotherapy resistance in prostate cancer. Moreover, our findings first emphasized the functional importance of IGF2BPs as epigenetic R-loop readers in transcriptional genetic regulation and cancer biology. In addition, our research provides a novel RBM15/IGF2BPs/DNMT1 trans-omics regulation m6A axis, indicating the new crosstalk between RNA m6A methylation and DNA methylation in prostate cancer.


Asunto(s)
Adenosina/análogos & derivados , Docetaxel , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Neoplasias de la Próstata , Estructuras R-Loop , Masculino , Humanos , Docetaxel/farmacología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Línea Celular Tumoral , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Adenosina/metabolismo , Adenosina/farmacología , Proliferación Celular , Resistencia a Antineoplásicos/genética , Regiones Promotoras Genéticas , Antineoplásicos/farmacología
2.
Anal Chem ; 96(1): 401-408, 2024 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-38134291

RESUMEN

Fluorescent lateral flow immunoassay (LFA) systems are versatile tools for sensitive and quantitative detection of disease markers at the point of care. However, traditional fluorescent nanoparticle-based lateral flow immunoassays are not visible under room light, necessitate an additional fluorescent reader, and lack flexibility for different application scenarios. Herein, we report a dual-readout LFA system for the rapid and sensitive detection of C-reactive protein (CRP) in clinical samples. The system relied on the aggregation-induced emission nanobeads (AIENBs) encapsulated with red AIE luminogen, which possesses both highly fluorescent and colorimetric properties. The AIENB-based LFA in the naked-eye mode was able to qualitatively detect CRP levels as low as 8.0 mg/L, while in the fluorescent mode, it was able to quantitatively measure high-sensitivity CRP (hs-CRP) with a limit of detection of 0.16 mg/L. The AIENB-based LFA system also showed a good correlation with the clinically used immunoturbidimetric method for CRP and hs-CRP detection in human plasma. This dual-modal AIENB-based LFA system offers the convenience of colorimetric testing and highly sensitive and quantitative detection of disease biomarkers and medical diagnostics in various scenarios.


Asunto(s)
Proteína C-Reactiva , Nanopartículas , Humanos , Sistemas de Atención de Punto , Inmunoensayo/métodos , Límite de Detección , Colorantes
3.
Cancer Cell Int ; 24(1): 68, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38341588

RESUMEN

BACKGROUND: Cuproptosis-related genes (CRGs) are associated with lung adenocarcinoma. However, the links between CRGs and non-small-cell lung cancer (NSCLC) are not clear. In this study, we aimed to develop two cuproptosis models and investigate their correlation with NSCLC in terms of clinical features and tumor microenvironment. METHODS: CRG expression profiles and clinical data from NSCLC and normal tissues was obtained from GEO (GSE42127) and TCGA datasets. Molecular clusters were classified into three patterns based on CRGs and cuproptosis cluster-related specific differentially expressed genes (CRDEGs). Then, two clinical models were established. First, a prognostic score model based on CRDEGs was established using univariate/multivariate Cox analysis. Then, through principal component analysis, a cuproptosis score model was established based on prognosis-related genes acquired via univariate analysis of CRDEGs. NSCLC patients were divided into high/low risk groups. RESULTS: Eighteen CRGs were acquired, all upregulated in tumor tissues, 15 of which significantly (P < 0.05). Among the three CRG clusters, cluster B had the best prognosis. In the CRDEG clusters, cluster C had the best survival. In the prognostic score model, the high-risk group had worse prognosis, higher tumor mutation load, and lower immune infiltration while in the cuproptosis score model, a high score represented better survival, lower tumor mutation load, and high-level immune infiltration. CONCLUSIONS: The cuproptosis score model and prognostic score model may be associated with NSCLC prognosis and immune microenvironment. These novel findings on the progression and immune landscape of NSCLC may facilitate the provision of more personalized immunotherapy interventions for NSCLC patients.

4.
Cancer Cell Int ; 24(1): 171, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750571

RESUMEN

BACKGROUND: As a highly heterogeneous tumor, non-small cell lung cancer (NSCLC) is famous for its high incidence and mortality worldwide. Smoking can cause genetic changes, which leading to the occurrence and progress of NSCLC. Nevertheless, the function of smoking-related genes in NSCLC needs more research. METHODS: We downloaded transcriptome data and clinicopathological parameters from Gene Expression Omnibus (GEO) databases, and screened smoking-related genes. Lasso regression were applied to establish the 7-gene signature. The associations between the 7-gene signature and immune microenvironment analysis, survival analysis, drug sensitivity analysis and enriched molecular pathways were studied. Ultimately, cell function experiments were conducted to research the function of FCGBP in NSCLC. RESULTS: Through 7-gene signature, NSCLC samples were classified into high-risk group (HRG) and low-risk group (LRG). Significant difference in overall survival (OS) between HRG and LRG was found. Nomograms and ROC curves indicated that the 7-gene signature has a stable ability in predicting prognosis. Through the analysis of immune microenvironment, we found that LRG patients had better tumor immune activation. FCGBP showed the highest mutation frequency among the seven prognostic smoking related genes (LRRC31, HPGD, FCGBP, SPINK5, CYP24A1, S100P and FGG), and was notable down-regulated in NSCLC smokers compared with non-smoking NSCLC patients. The cell experiments confirmed that FCGBP knockdown promoting proliferation, migration, and invasion in NSCLC cells. CONCLUSION: This smoking-related prognostic signature represents a promising tool for assessing prognosis and tumor microenvironment in smokers with NSCLC. The role of FCGBP in NSCLC was found by cell experiments, which can be served as diagnostic biomarker and immunotherapy target for NSCLC.

5.
Nucleic Acids Res ; 49(3): 1313-1329, 2021 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-33434283

RESUMEN

DNA methylation is important for the epigenetic regulation of gene expression and plays a critical role in mammalian development. However, the dynamic regulation of genome-wide DNA methylation in skeletal muscle development remains largely unknown. Here, we generated the first single-base resolution DNA methylome and transcriptome maps of porcine skeletal muscle across 27 developmental stages. The overall methylation level decreased from the embryo to the adult, which was highly correlated with the downregulated expression of DNMT1 and an increase in partially methylated domains. Notably, we identified over 40 000 developmentally differentially methylated CpGs (dDMCs) that reconstitute the developmental trajectory of skeletal muscle and associate with muscle developmental genes and transcription factors (TFs). The dDMCs were significantly under-represented in promoter regulatory regions but strongly enriched as enhancer histone markers and in chromatin-accessible regions. Integrative analysis revealed the negative regulation of both promoter and gene body methylation in genes associated with muscle contraction and insulin signaling during skeletal muscle development. Mechanistically, DNA methylation affected the expression of muscle-related genes by modulating the accessibly of upstream myogenesis TF binding, indicating the involvement of the DNA methylation/SP1/IGF2BP3 axis in skeletal myogenesis. Our results highlight the function and regulation of dynamic DNA methylation in skeletal muscle development.


Asunto(s)
Metilación de ADN , Epigenoma , Desarrollo de Músculos/genética , Músculo Esquelético/embriología , Músculo Esquelético/crecimiento & desarrollo , Animales , Línea Celular , Islas de CpG , Epigénesis Genética , Femenino , Masculino , Músculo Esquelético/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Caracteres Sexuales , Factor de Transcripción Sp1/metabolismo , Porcinos , Transcriptoma
6.
Entropy (Basel) ; 25(2)2023 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-36832665

RESUMEN

This article offers an optimal control tracking method using an event-triggered technique and the internal reinforcement Q-learning (IrQL) algorithm to address the tracking control issue of unknown nonlinear systems with multiple agents (MASs). Relying on the internal reinforcement reward (IRR) formula, a Q-learning function is calculated, and then the iteration IRQL method is developed. In contrast to mechanisms triggered by time, an event-triggered algorithm reduces the rate of transmission and computational load, since the controller may only be upgraded when the predetermined triggering circumstances are met. In addition, in order to implement the suggested system, a neutral reinforce-critic-actor (RCA) network structure is created that may assess the indices of performance and online learning of the event-triggering mechanism. This strategy is intended to be data-driven without having in-depth knowledge of system dynamics. We must develop the event-triggered weight tuning rule, which only modifies the parameters of the actor neutral network (ANN) in response to triggering cases. In addition, a Lyapunov-based convergence study of the reinforce-critic-actor neutral network (NN) is presented. Lastly, an example demonstrates the accessibility and efficiency of the suggested approach.

7.
Angew Chem Int Ed Engl ; 62(43): e202309362, 2023 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-37640689

RESUMEN

Ergothioneine (ESH) and ovothiol A (OSHA) are two natural thiol-histidine derivatives. ESH has been implicated as a longevity vitamin and OSHA inhibits the proliferation of hepatocarcinoma. The key biosynthetic step of ESH and OSHA in the aerobic pathways is the O2 -dependent C-S bond formation catalyzed by non-heme iron enzymes (e.g., OvoA in ovothiol biosynthesis), but due to the lack of identification of key reactive intermediate the mechanism of this novel reaction is unresolved. In this study, we report the identification and characterization of a kinetically competent S=1 iron(IV) intermediate supported by a four-histidine ligand environment (three from the protein residues and one from the substrate) in enabling C-S bond formation in OvoA from Methyloversatilis thermotoleran, which represents the first experimentally observed intermediate spin iron(IV) species in non-heme iron enzymes. Results reported in this study thus set the stage to further dissect the mechanism of enzymatic oxidative C-S bond formation in the OSHA biosynthesis pathway. They also afford new opportunities to study the structure-function relationship of high-valent iron intermediates supported by a histidine rich ligand environment.


Asunto(s)
Histidina , Hierro , Histidina/metabolismo , Ligandos , Catálisis , Estrés Oxidativo
8.
J Gen Virol ; 103(4)2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35438623

RESUMEN

The expression of various forms of hepatitis B virus (HBV) surface proteins regulates the release of mature virion, but whether they affect the release of other incomplete viral particles, such as naked capsid, is not clear. Here, by stable overexpression of large or middle/small hepatitis B surface proteins (LHBs, M/SHBs) in HepAD38 cells, we evaluated their effects on the release of complete and incomplete viral particles. Overproduction of LHBs inhibited the release of all surface proteins, which increased the ratio of naked capsids/virions. This effect was accompanied by the elevated extracellular HBV RNA. On the other hand, overexpression of M/SHBs greatly improved the secretion of enveloped viral and subviral particles. In situ visualization of viral DNA and LHBs revealed intracellular retention of mature virions when LHBs were overexpressed. These results indicate that the molecular decision on secretion of enveloped or unenveloped viral particles is modulated by the intracellular ratio of large, middle and small surface antigens. This mechanism may be relevant in the progression and resolution of HBV-induced chronic liver disease.


Asunto(s)
Virus de la Hepatitis B , Hepatitis B , Proteínas de la Cápside/metabolismo , ADN Viral/genética , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Humanos , Proteínas de la Membrana , Virión/genética , Replicación Viral
9.
Genet Sel Evol ; 54(1): 62, 2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36104777

RESUMEN

BACKGROUND: The genetic mechanisms that underlie phenotypic differentiation in breeding animals have important implications in evolutionary biology and agriculture. However, the contribution of cis-regulatory variants to pig phenotypes is poorly understood. Therefore, our aim was to elucidate the molecular mechanisms by which non-coding variants cause phenotypic differences in pigs by combining evolutionary biology analyses and functional genomics. RESULTS: We obtained a high-resolution phased chromosome-scale reference genome with a contig N50 of 18.03 Mb for the Luchuan pig breed (a representative eastern breed) and profiled potential selective sweeps in eastern and western pigs by resequencing the genomes of 234 pigs. Multi-tissue transcriptome and chromatin accessibility analyses of these regions suggest that tissue-specific selection pressure is mediated by promoters and distal cis-regulatory elements. Promoter variants that are associated with increased expression of the lysozyme (LYZ) gene in the small intestine might enhance the immunity of the gastrointestinal tract and roughage tolerance in pigs. In skeletal muscle, an enhancer-modulating single-nucleotide polymorphism that is associated with up-regulation of the expression of the troponin C1, slow skeletal and cardiac type (TNNC1) gene might increase the proportion of slow muscle fibers and affect meat quality. CONCLUSIONS: Our work sheds light on the molecular mechanisms by which non-coding variants shape phenotypic differences in pigs and provides valuable resources and novel perspectives to dissect the role of gene regulatory evolution in animal domestication and breeding.


Asunto(s)
Genoma , Genómica , Animales , Evolución Molecular , Fenotipo , Análisis de Secuencia de ADN , Porcinos/genética
10.
RNA Biol ; 18(sup1): 439-450, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34314293

RESUMEN

RNA editing generates genetic diversity in mammals by altering amino acid sequences, miRNA targeting site sequences, influencing the stability of targeted RNAs, and causing changes in gene expression. However, the extent to which RNA editing affect gene expression via modifying miRNA binding site remains unexplored. Here, we first profiled the dynamic A-to-I RNA editome across tissues of Duroc and Luchuan pigs. The RNA editing events at the miRNA binding sites were generated. The biological function of the differentially edited gene in skeletal muscle was further characterized in pig muscle-derived satellite cells. RNA editome analysis revealed a total of 171,909 A-to-I RNA editing sites (RESs), and examination of its features showed that these A-to-I editing sites were mainly located in SINE retrotransposons PRE-1/Pre0_SS element. Analysis of differentially edited sites (DESs) revealed a total of 4,552 DESs across tissues between Duroc and Luchuan pigs, and functional category enrichment analysis of differentially edited gene (DEG) sets highlighted a significant association and enrichment of tissue-developmental pathways including TGF-beta, PI3K-Akt, AMPK, and Wnt signaling pathways. Moreover, we found that RNA editing events at the miRNA binding sites in the 3'-UTR of HSPA12B mRNA could prevent the miRNA-mediated mRNA downregulation of HSPA12B in the muscle-derived satellite (MDS) cell, consistent with the results obtained from the Luchuan skeletal muscle. This study represents the most systematic attempt to characterize the significance of RNA editing in regulating gene expression, particularly in skeletal muscle, constituting a new layer of regulation to understand the genetic mechanisms behind phenotype variance in animals.Abbreviations: A-to-I: Adenosine-to-inosine; ADAR: Adenosine deaminase acting on RNA; RES: RNA editing site; DEG: Differentially edited gene; DES: Differentially edited site; FDR: False discovery rate; GO: Gene Ontology; KEGG: Kyoto Encyclopaedia of Genes and Genomes; MDS cell: musclederived satellite cell; RPKM: Reads per kilobase of exon model in a gene per million mapped reads; UTR: Untranslated coding regions.


Asunto(s)
Regiones no Traducidas 3'/genética , Regulación de la Expresión Génica , MicroARNs/genética , Edición de ARN , ARN Mensajero/genética , Retroelementos , Animales , MicroARNs/metabolismo , Especificidad de Órganos , ARN Mensajero/metabolismo , Porcinos
11.
BMC Anesthesiol ; 21(1): 272, 2021 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-34749669

RESUMEN

BACKGROUND: Sleep deprivation (SD) often leads to complex detrimental consequences, though the mechanisms underlying these dysfunctional effects remain largely unknown. We investigated whether the right stellate ganglion block in rats can improve the spatial learning and memory dysfunction induced by sleep deprivation by alleviating the damage of hippocampus in rats. METHODS: Sixty four male Sprague Dawley rats were randomly divided into four groups: Control, SD (sleep deprivation), SGB (stellate ganglion block) and SGB + SD (stellate ganglion block+ sleep deprivation) (n = 16). The SGB and SD + SGB groups were subjected to right stellate ganglion block through posterior approach method once per day. SD and SD + SGB groups were treated with modified multi-platform water environment method for 96 h sleep deprivation in rats and their body weights were analyzed. Histopathological changes of hippocampal neurons in rats and the expression of Caspase-3 in hippocampus of rats was detected by western blotting. ELISA was used to detect the content of IL-6, IL-1 in hippocampus and serum melatonin levels. RESULTS: Compared with the group SD, the spatial learning and memory function of the group SD + SGB was improved, the weight loss was alleviated, the pathological damage of the hippocampus was reduced and the expression of IL-6, IL-1ß and Caspase-3 in the hippocampus was decreased. The content of rat serum melatonin was also increased. CONCLUSIONS: The right stellate ganglion block can improve the spatial learning and memory dysfunction of rats with sleep deprivation, and the underlying mechanism may be related to alleviating the apoptosis and inflammation of hippocampus of rats with sleep deprivation.


Asunto(s)
Bloqueo Nervioso Autónomo/métodos , Trastornos de la Memoria/terapia , Privación de Sueño/complicaciones , Ganglio Estrellado , Animales , Hipocampo/patología , Masculino , Melatonina/sangre , Trastornos de la Memoria/etiología , Neuronas/patología , Ratas , Ratas Sprague-Dawley , Privación de Sueño/fisiopatología , Aprendizaje Espacial/fisiología
12.
Sensors (Basel) ; 21(21)2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34770400

RESUMEN

It is commonplace for people to perform various kinds of activities in groups. The recognition of human groups is of importance in many applications including crowd evacuation, teamwork coordination, and advertising. Existing group recognition approaches require snapshots of human trajectories, which is often impossible in the reality due to different data collection start time and frequency, and the inherent time deviations of devices. This study proposes an approach to synchronize the data of people for group recognition. All people's trajectory data are aligned by using data interpolating. The optimal interpolating points are computed based on our proposed error function. Moreover, the time deviations among devices are estimated and eliminated by message passing. A real-life data set is used to validate the effectiveness of the proposed approach. The results show that 97.7% accuracy of group recognition can be achieved. The approach proposed to deal with time deviations was also proven to lead to better performance compared to that of the existing approaches.


Asunto(s)
Reconocimiento en Psicología , Recolección de Datos , Humanos
13.
J Cell Mol Med ; 24(8): 4830-4838, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32160650

RESUMEN

Nowadays, research on CSCs is still in an initial stage, and there are few studies reporting the successful isolation and identification of CSCs. In the present study, we attempted to isolate CSCs through cultivating the cell line MKN45 in defined serum-free medium and study the expression of stem cell markers or related proteins (Oct3/4, Sox2, Nanog and CD44) in CSCs. Moreover, immunofluorescence staining was performed to validate the stem cell markers of spheroid body-forming cells. Further experiments were used to evaluate the SPOP expression in tumorsphere cells. In addition, ADAMTS9-AS2 is a lncRNA that contributes to the genesis and development of many cancers, including gastric cancer (GC). We found ADAMTS9-AS2 functioned as an anti-oncogene and positively correlated with the expression of SPOP in GC tissues by combining bioinformatics analyses. Furthermore, we reported that ADAMTS9-AS2 regulated the expression of SPOP in GC cells and tumorsphere cells to inhibit GC progression. Together, our results demonstrated that SPOP and ADAMTS9-AS2 can be potential targets for GC treatment.


Asunto(s)
Proliferación Celular/genética , Proteínas Nucleares/genética , ARN Largo no Codificante/genética , Proteínas Represoras/genética , Neoplasias Gástricas/genética , Animales , Pruebas de Carcinogenicidad , Línea Celular Tumoral , Movimiento Celular/genética , Regulación Neoplásica de la Expresión Génica/genética , Xenoinjertos , Humanos , Ratones , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Transducción de Señal/genética , Neoplasias Gástricas/patología
14.
J Am Chem Soc ; 142(13): 6268-6284, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-32131594

RESUMEN

Mechanisms of enzymatic epoxidation via oxygen atom transfer (OAT) to an olefin moiety is mainly derived from the studies on thiolate-heme containing epoxidases, such as cytochrome P450 epoxidases. The molecular basis of epoxidation catalyzed by nonheme-iron enzymes is much less explored. Herein, we present a detailed study on epoxidation catalyzed by the nonheme iron(II)- and 2-oxoglutarate-dependent (Fe/2OG) oxygenase, AsqJ. The native substrate and analogues with different para substituents ranging from electron-donating groups (e.g., methoxy) to electron-withdrawing groups (e.g., trifluoromethyl) were used to probe the mechanism. The results derived from transient-state enzyme kinetics, Mössbauer spectroscopy, reaction product analysis, X-ray crystallography, density functional theory calculations, and molecular dynamic simulations collectively revealed the following mechanistic insights: (1) The rapid O2 addition to the AsqJ Fe(II) center occurs with the iron-bound 2OG adopting an online-binding mode in which the C1 carboxylate group of 2OG is trans to the proximal histidine (His134) of the 2-His-1-carboxylate facial triad, instead of assuming the offline-binding mode with the C1 carboxylate group trans to the distal histidine (His211); (2) The decay rate constant of the ferryl intermediate is not strongly affected by the nature of the para substituents of the substrate during the OAT step, a reactivity behavior that is drastically different from nonheme Fe(IV)-oxo synthetic model complexes; (3) The OAT step most likely proceeds through a stepwise process with the initial formation of a C(benzylic)-O bond to generate an Fe-alkoxide species, which is observed in the AsqJ crystal structure. The subsequent C3-O bond formation completes the epoxide installation.


Asunto(s)
Aspergillus nidulans/metabolismo , Compuestos Epoxi/metabolismo , Proteínas Fúngicas/metabolismo , Ácidos Cetoglutáricos/metabolismo , Oxígeno/metabolismo , Oxigenasas/metabolismo , Aspergillus nidulans/química , Aspergillus nidulans/enzimología , Cristalografía por Rayos X , Compuestos Epoxi/química , Proteínas Fúngicas/química , Hierro/química , Hierro/metabolismo , Modelos Moleculares , Oxígeno/química , Oxigenasas/química
15.
BMC Cardiovasc Disord ; 20(1): 475, 2020 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-33148187

RESUMEN

BACKGROUND: BRD4 and PIN1 have been described to be involved in inflammation and vascular endothelial cell dysfunction, which in turn may increase pulse pressure. HYPOTHESIS: Genetic mutations within the BRD4 and PIN1 genes could affect the risk of high pulse pressure. METHODS: A total of four single nucleotide polymorphisms (SNPs) (BRD4: rs4808278; PIN1: rs2233678, rs2287838, and rs2233682) were genotyped in a cohort of 666 hypertensive patients and 232 normotensive controls with Chinese Han origin. Generalized multifactor dimensionality reduction (GMDR) was used to screen the best interaction combination among the four SNPs within the BRD4 and PIN1 genes and diabetes. Logistic regression analysis was performed to calculate the odds ratio (ORs) (95% confidence interval (CI)) for the association between the four SNPs. RESULTS: Adjusted for age, weight, waist circumference, drinking, smoking, hypertension, and diabetes, high pulse pressure risk was significantly higher for carriers with the rs4808278-TT genotype in BRD4 than those with wild genotypes (OR: 0.400, 95% CI: 0.217-0.737, P* < 0.05). However, we did not find any significant association of rs2233678, rs2287838, and rs2233682 in PIN1 with high pulse pressure susceptibility after covariate adjustment. GMDR analysis indicated a significant three-locus model (P = 0.0107) involving rs4808278, rs2233678, and diabetes, the cross-validation consistency of the three-locus models was 9/10, and the testing accuracy was 57.47%. CONCLUSIONS: Genetic mutations within BRD4 (rs4808278) could affect the susceptibility to high pulse pressure in a southeastern Chinese population.


Asunto(s)
Presión Sanguínea/genética , Proteínas de Ciclo Celular/genética , Hipertensión/genética , Peptidilprolil Isomerasa de Interacción con NIMA/genética , Polimorfismo de Nucleótido Simple , Factores de Transcripción/genética , Adulto , Anciano , Pueblo Asiatico/genética , China/epidemiología , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Hipertensión/diagnóstico , Hipertensión/etnología , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Fenotipo , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo
16.
Angew Chem Int Ed Engl ; 59(19): 7367-7371, 2020 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-32074393

RESUMEN

N-alkylisonitrile, a precursor to isonitrile-containing lipopeptides, is biosynthesized by decarboxylation-assisted -N≡C group (isonitrile) formation by using N-alkylglycine as the substrate. This reaction is catalyzed by iron(II) and 2-oxoglutarate (Fe/2OG) dependent enzymes. Distinct from typical oxygenation or halogenation reactions catalyzed by this class of enzymes, installation of the isonitrile group represents a novel reaction type for Fe/2OG enzymes that involves a four-electron oxidative process. Reported here is a plausible mechanism of three Fe/2OG enzymes, Sav607, ScoE and SfaA, which catalyze isonitrile formation. The X-ray structures of iron-loaded ScoE in complex with its substrate and the intermediate, along with biochemical and biophysical data reveal that -N≡C bond formation involves two cycles of Fe/2OG enzyme catalysis. The reaction starts with an FeIV -oxo-catalyzed hydroxylation. It is likely followed by decarboxylation-assisted desaturation to complete isonitrile installation.


Asunto(s)
Glicina/síntesis química , Hierro/química , Nitrilos/síntesis química , Procolágeno-Lisina 2-Oxoglutarato 5-Dioxigenasa/química , Catálisis , Glicina/análogos & derivados , Hidroxilación , Modelos Moleculares , Resonancia Magnética Nuclear Biomolecular , Oxidación-Reducción , Difracción de Rayos X
17.
Biochemistry ; 57(12): 1838-1841, 2018 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-29485871

RESUMEN

Two non-heme iron enzymes, IsnB and AmbI3, catalyze a novel decarboxylation-assisted olefination to produce indole vinyl isonitrile, an important building block for many natural products. Compared to other reactions catalyzed by this enzyme family, decarboxylation-assisted olefination represents an attractive biosynthetic route and a mechanistically unexplored pathway in constructing a C═C bond. Using mechanistic probes, transient state kinetics, reactive intermediate trapping, spectroscopic characterizations, and product analysis, we propose that both IsnB and AmbI3 initiate stereoselective olefination via a benzylic C-H bond activation by an Fe(IV)-oxo intermediate, and the reaction likely proceeds through a radical- or carbocation-induced decarboxylation to complete C═C bond installation.


Asunto(s)
Carboxiliasas/química , Hierro/química , Ácidos Cetoglutáricos/química , Catálisis
18.
J Am Chem Soc ; 140(45): 15190-15193, 2018 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-30376630

RESUMEN

Installation of olefins into molecules is a key transformation in organic synthesis. The recently discovered decarboxylation-assisted olefination in the biosynthesis of rhabduscin by a mononuclear non-heme iron enzyme ( P.IsnB) represents a novel approach in olefin construction. This method is commonly employed in natural product biosynthesis. Herein, we demonstrate that a ferryl intermediate is used for C-H activation at the benzylic position of the substrate. We further establish that P.IsnB reactivity can be switched from olefination to hydroxylation using electron-withdrawing groups appended on the phenyl moiety of the analogues. These experimental observations imply that a pathway involving an initial C-H activation followed by a benzylic carbocation species or by electron transfer coupled ß-scission is likely utilized to complete C═C bond formation.


Asunto(s)
Alquenos/metabolismo , Proteínas de Hierro no Heme/metabolismo , Alquenos/química , Biocatálisis , Descarboxilación , Estructura Molecular
19.
Angew Chem Int Ed Engl ; 57(36): 11752-11757, 2018 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-29987910

RESUMEN

Dynamically engineering the interfacial interaction of nanoparticles has emerged as a new approach for bottom-up fabrication of smart systems to tailor molecular diffusion and controlled release. Janus zwitterionic nanoplates are reported that can be switched between a locked and unlocked state at interfaces upon changing surface charge, allowing manipulation of interfacial properties in a fast, flexible, and switchable manner. Combining experimental and modeling studies, an unambiguous correlation is established among the electrostatic energy, the interface geometry, and the interfacial jamming states. As a proof-of-concept, the well-controlled interfacial jamming of nanoplates enabled the switchable molecular diffusion through liquid-liquid interfaces, confirming the feasibility of using nanoparticle-based surfactants for advanced controlled release.

20.
J Med Virol ; 89(4): 589-597, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27632796

RESUMEN

Respiratory syncytial virus (RSV) and human metapneumovirus (HMPV) are two common viral pathogens in acute lower respiratory tract infections (ALRTI). However, the association of viral load with clinical characteristics is not well-defined in ALRTI. To explore the correlation between viral load and clinical characteristics of RSV and HMPV in children hospitalized for ALRTI in Lanzhou, China. Three hundred and eighty-seven children hospitalized for ALRTI were enrolled. Nasopharyngeal aspirates (NPAs) were sampled from each children. Real-time PCR was used to screen RSV, HMPV, and twelve additional respiratory viruses. Bronchiolitis was the leading diagnoses both in RSV and HMPV positive patients. A significantly greater frequency of wheezing (52% vs. 33.52%, P = 0.000) was noted in RSV positive and negative patients. The RSV viral load was significant higher in children aged <1 year (P = 0.003), children without fever and wheezing (P = 0.015 and P = 0.000), days of illness <14 days (P = 0.002), children with bronchiolitis (P = 0.012) and children with RSV single infections (P = 0.000). No difference was found in the clinical features of HMPV positive and negative patients. The HMPV viral load had no correlation with any clinical characteristics. The incidences of severe disease were similar between single infection and coinfection for the two viruses (RSV, P = 0.221; HMPV, P = 0.764) and there has no statistical significance between severity and viral load (P = 0.166 and P = 0.721). Bronchiolitis is the most common disease caused by RSV and HMPV. High viral load or co-infection may be associated with some symptoms but neither has a significant impact on disease severity for the two viruses. J. Med. Virol. 89:589-597, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Metapneumovirus/aislamiento & purificación , Infecciones por Paramyxoviridae/patología , Infecciones por Virus Sincitial Respiratorio/patología , Virus Sincitial Respiratorio Humano/aislamiento & purificación , Infecciones del Sistema Respiratorio/patología , Carga Viral , Adolescente , Niño , Preescolar , China , Femenino , Hospitalización , Humanos , Lactante , Recién Nacido , Masculino , Nasofaringe/virología , Infecciones por Paramyxoviridae/virología , Reacción en Cadena en Tiempo Real de la Polimerasa , Infecciones por Virus Sincitial Respiratorio/virología , Infecciones del Sistema Respiratorio/virología
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