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1.
Nucleic Acids Res ; 52(13): 7665-7686, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38850159

RESUMEN

Genomic instability is one of the hallmarks of cancer. While loss of histone demethylase KDM6A increases the risk of tumorigenesis, its specific role in maintaining genomic stability remains poorly understood. Here, we propose a mechanism in which KDM6A maintains genomic stability independently on its demethylase activity. This occurs through its interaction with SND1, resulting in the establishment of a protective chromatin state that prevents replication fork collapse by recruiting of RPA and Ku70 to nascent DNA strand. Notably, KDM6A-SND1 interaction is up-regulated by KDM6A SUMOylation, while KDM6AK90A mutation almost abolish the interaction. Loss of KDM6A or SND1 leads to increased enrichment of H3K9ac and H4K8ac but attenuates the enrichment of Ku70 and H3K4me3 at nascent DNA strand. This subsequently results in enhanced cellular sensitivity to genotoxins and genomic instability. Consistent with these findings, knockdown of KDM6A and SND1 in esophageal squamous cell carcinoma (ESCC) cells increases genotoxin sensitivity. Intriguingly, KDM6A H101D & P110S, N1156T and D1216N mutations identified in ESCC patients promote genotoxin resistance via increased SND1 association. Our finding provides novel insights into the pivotal role of KDM6A-SND1 in genomic stability and chemoresistance, implying that targeting KDM6A and/or its interaction with SND1 may be a promising strategy to overcome the chemoresistance.


Asunto(s)
Resistencia a Antineoplásicos , Inestabilidad Genómica , Histona Demetilasas , Humanos , Inestabilidad Genómica/genética , Resistencia a Antineoplásicos/genética , Histona Demetilasas/metabolismo , Histona Demetilasas/genética , Línea Celular Tumoral , Mutación , Histonas/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Sumoilación , Endonucleasas/metabolismo , Endonucleasas/genética , Replicación del ADN , Cromatina/metabolismo , Cromatina/genética , Autoantígeno Ku/metabolismo , Autoantígeno Ku/genética
2.
Cell Mol Life Sci ; 81(1): 26, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38212548

RESUMEN

Mitochondria serve as essential organelles that play a key role in regulating stem cell fate. Mitochondrial dysfunction and stem cell exhaustion are two of the nine distinct hallmarks of aging. Emerging research suggests that epigenetic modification of mitochondria-encoded genes and the regulation of epigenetics by mitochondrial metabolites have an impact on stem cell aging or differentiation. Here, we review how key mitochondrial metabolites and behaviors regulate stem cell fate through an epigenetic approach. Gaining insight into how mitochondria regulate stem cell fate will help us manufacture and preserve clinical-grade stem cells under strict quality control standards, contributing to the development of aging-associated organ dysfunction and disease.


Asunto(s)
Mitocondrias , Células Madre , Diferenciación Celular/genética , Mitocondrias/metabolismo , Epigénesis Genética , Senescencia Celular , ADN Mitocondrial/genética
3.
Mol Microbiol ; 119(1): 126-142, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36537557

RESUMEN

In dimorphic fungi, the yeast-to-filament transition critical for cell survival under nutrient starvation is controlled by both activators and repressors. However, very few filamentation repressors are known. Here we report that, in the dimorphic yeast Yarrowia lipolytica, the conserved transcription factor YlNrg1 plays a minor role whereas Fts1, a newly identified Zn(II)2 Cys6 zinc cluster transcription factor, plays a key role in filamentation repression. FTS1 deletion caused hyperfilamentation whereas Fts1 overexpression drastically reduced filamentation. The expression of FTS1 is downregulated substantially during the yeast-to-filament transition. Transcriptome sequencing revealed that Fts1 represses 401 genes, including the filamentation-activating transcription factor genes MHY1, YlAZF1, and YlWOR4 and key cell wall protein genes. Tup1-Ssn6, a general transcriptional corepressor, is involved in the repression of many cellular functions in fungi. We show that both YlTup1 and YlSsn6 strongly repress filamentation in Y. lipolytica. YlTup1 and YlSsn6 together repress 1383 genes, including a large number of transcription factor and cell wall protein genes, which overlap substantially with Fts1-repressed genes. Fts1 interacts with both YlTup1 and YlSsn6, and LexA-Fts1 fusion represses a lexAop-promoter-lacZ reporter in a Tup1-Ssn6-dependent manner. Our findings suggest that Fts1 functions as a transcriptional repressor, directing the repression of target genes through the Tup1-Ssn6 corepressor.


Asunto(s)
Yarrowia , Proteínas Co-Represoras/genética , Proteínas Co-Represoras/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica/genética , Regiones Promotoras Genéticas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Yarrowia/genética , Yarrowia/metabolismo
4.
Biochem Biophys Res Commun ; 739: 150550, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39181070

RESUMEN

In plants, cytochrome P450s are monooxygenase that play key roles in the synthesis and degradation of intracellular substances. In tobacco, the majority of studies examining the P450 superfamily have concentrated on the CYP82E subfamily, where multiple family members function as demethylases, facilitating the synthesis of nornicotine. In this study, NtCYP82C4, a tobacco P450 superfamily member, was identified from a gene-edited tobacco mutant that nicotine biosynthesis in tobacco leaves is evidently reduced. Compared to the wild-type plants, the knockout of NtCYP82C4 resulted in a significantly lower nicotine content and biomass in tobacco leaves. Transcriptome and metabolome analyses indicated that the knockout of NtCYP82C4 inhibites secondary metabolic processes in tobacco plants, leading to the accumulation of some important precursors in the nicotine synthesis process, including aspartic acid and nicotinic acid, and increases nitrogen partitioning associated with those processes such as amino acid synthesis and utilization. It is speculated that NtCYP82C4 may function as an important catalase downstream of the nicotine synthesis. Currently, most of the steps and enzymes involved in the nicotine biosynthesis process in tobacco have been elucidated. Here, our study deepens the current understanding of nicotine biosynthesis process and provides new enzyme targets for nicotine synthesis in tobacco plants.

5.
Mol Genet Genomics ; 299(1): 13, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38396305

RESUMEN

Gamma (γ)-ray irradiation is one of the important modern breeding methods. Gamma-ray irradiation can affect the growth rate and other characteristics of plants. Plant growth rate is crucial for plants. In horticultural crops, the growth rate of plants is closely related to the growth of leaves and flowering time, both of which have important ornamental value. In this study, 60Co-γ-ray was used to treat P. equestris plants. After irradiation, the plant's leaf growth rate increased, and sugar content and antioxidant enzyme activity increased. Therefore, we used RNA-seq technology to analyze the differential gene expression and pathways of control leaves and irradiated leaves. Through transcriptome analysis, we investigated the reasons for the rapid growth of P. equestris leaves after irradiation. In the analysis, genes related to cell wall relaxation and glucose metabolism showed differential expression. In addition, the expression level of genes encoding ROS scavenging enzyme synthesis regulatory genes increased after irradiation. We identified two genes related to P. equestris leaf growth using VIGS technology: PeNGA and PeEXPA10. The expression of PeEXPA10, a gene related to cell wall expansion, was down-regulated, cell wall expansion ability decreased, cell size decreased, and leaf growth rate slowed down. The TCP-NGATHA (NGA) molecular regulatory module plays a crucial role in cell proliferation. When the expression of the PeNGA gene decreases, the leaf growth rate increases, and the number of cells increases. After irradiation, PeNGA and PeEXPA10 affect the growth of P. equestris leaves by influencing cell proliferation and cell expansion, respectively. In addition, many genes in the plant hormone signaling pathway show differential expression after irradiation, indicating the crucial role of plant hormones in plant leaf growth. This provides a theoretical basis for future research on leaf development and biological breeding.


Asunto(s)
Orchidaceae , Fitomejoramiento , Perfilación de la Expresión Génica , Genes de Plantas , RNA-Seq , Antioxidantes/metabolismo , Orchidaceae/genética , Orchidaceae/metabolismo , Hojas de la Planta , Regulación de la Expresión Génica de las Plantas , Transcriptoma/genética
6.
Chemistry ; : e202402806, 2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39180461

RESUMEN

Tunable luminescence-assisted information storage and encryption holds increasing significance in today's society. A promising approach to incorporating the benefits of both organic long persistent luminescent (LPL) materials and rare-earth (RE) luminescence lies in utilizing organic host materials to sensitize RE luminescence, as well as hydrogen-bonded organic framework (HOF) phosphorescence Förster resonance energy transfer to RE compound luminescence. This work introduces a one-pot, in situ pyrolytic condensation method, achieved through high-temperature melting calcination, to synthesize lanthanide ion-doped HOF materials. This method circumvents the drawback of molecular triplet energy annihilation, enabling the creation of organic LPL materials with RE characteristics. The HOF material serves as the host, exhibiting blue phosphorescence and cyan LPL. By fine-tuning the doping amount, the composite material U-Tb-100 achieves green LPL with a luminescent quantum yield of 56.4%, and an LPL duration of approximately 2-3 s, demonstrating tunable persistence. Single-crystal X-ray diffraction, spectral analysis, and theoretical calculation unveil that U-Tb-100 exhibits exceptional quantum yield and long-lived luminescence primarily due to the efficient sensitization of U monomer to RE ions and the PRET process between U and RE complexes. This ingenious strategy not only expands the repertoire of HOF materials but also facilitates the design of multifunctional LPL materials.

7.
J Org Chem ; 89(8): 5560-5572, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38564232

RESUMEN

A simple, efficient, and practical method for the synthesis of S-quinolyl xanthates was developed via Ts2O-promoted deoxygenative C-H dithiocarbonation of quinoline N-oxides with various potassium O-alkyl xanthates. The reaction performed well under transition-metal-free, base-free, and room-temperature conditions with wide substrate tolerance. Employing potassium O-tert-butyl xanthate (tBuOCS2K) as a nucleophile, some valuable quinoline-2-thiones were unexpectedly obtained in a one-pot reaction without any additional base.

8.
Int J Legal Med ; 138(4): 1255-1264, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38416217

RESUMEN

Massively parallel sequencing allows for integrated genotyping of different types of forensic markers, which reduces DNA consumption, simplifies experimental processes, and provides additional sequence-based genetic information. The STRseqTyper122 kit genotypes 63 autosomal STRs, 16 X-STRs, 42 Y-STRs, and the Amelogenin locus. Amplicon sizes of 117 loci were below 300 bp. In this study, MiSeq FGx sequencing metrics for STRseqTyper122 were presented. The genotyping accuracy of this kit was examined by comparing to certified genotypes of NIST standard reference materials and results from five capillary electrophoresis-based kits. The sensitivity of STRseqTyper122 reached 125 pg, and > 80% of the loci were correctly called with 62.5 pg and 31.25 pg input genomic DNA. Repeatability, species specificity, and tolerance for DNA degradation and PCR inhibitors of this kit were also evaluated. STRseqTyper122 demonstrated reliable performance with routine case-work samples and provided a powerful tool for forensic applications.


Asunto(s)
Dermatoglifia del ADN , Secuenciación de Nucleótidos de Alto Rendimiento , Repeticiones de Microsatélite , Humanos , Dermatoglifia del ADN/métodos , Amelogenina/genética , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN/métodos , Genotipo , Reacción en Cadena de la Polimerasa , Especificidad de la Especie , Masculino , Animales , Degradación Necrótica del ADN , Electroforesis Capilar , Femenino
9.
Inorg Chem ; 63(2): 1188-1196, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38175718

RESUMEN

Metal-organic frameworks (MOFs) with long persistent luminescence (LPL) have attracted extensive research attention from researchers due to their potential applications in information encryption, anticounterfeiting technology, and security logic. In contrast to short-lived fluorescent materials, LPL materials offer a visible response that can be easily distinguished by the naked eye, thereby facilitating a much clearer visualization. However, there are few reports on functional LPL MOF materials as probes. In this article, two amino-functional LPL MOFs (VB4-2D and VB4-1D) were synthesized. They both exhibited adjustable fluorescence and phosphorescence from blue to green and from cyan to green, respectively. Notably, the MOFs emitted bright and adjustable LPL upon the removal of the different radiation sources. The basic amino functional groups in the MOFs exhibited acid and ammonia sensitivity, and fluorescence and phosphorescence emission intensities can be burst and restored in two atmospheres, respectively, which can be cycled multiple times. Furthermore, LPL intensity undergoes switching between two different conditions as well, which can be visually discerned by the naked eye, enabling visual sensing of volatiles by LPL. This combination of photoluminescence and the visual LPL switching behavior of acids and bases in functional MOFs may provide an effective avenue for stimulus response, anticounterfeiting, and encryption applications.

10.
Org Biomol Chem ; 22(8): 1646-1653, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38305467

RESUMEN

GaCl3-mediated one-pot cyclocondensation of o-allylbenzaldehydes and 1,3-dicarbonyls generates benzofused 8-oxabicyclo[3.3.1]nonanes in moderate to good yields in refluxing MeNO2 under easy-operational conditions. A plausible mechanism is proposed and discussed here. In the overall reaction process, various metal chloride-promoted conditions were investigated for one-pot cyclocondensation.

11.
Org Biomol Chem ; 22(6): 1194-1204, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38224195

RESUMEN

The synthesis of 4-sulfonyl-1,7-diesters was well developed, under open-vessel conditions, by K2CO3-mediated double alkylation of α-sulfonyl o-hydroxyacetophenones with acrylates and tandem debenzoylation of the resulting α,α-disubstituted o-hydroxyacetophenones. A plausible mechanism is proposed and discussed here. This high-yielding protocol provides a highly effective intermolecular alkylation and intramolecular debenzoylation via the formation of two carbon-carbon (C-C) single bonds and the cleavage of a carbon-carbon (C-C) single bond.

12.
Org Biomol Chem ; 22(20): 4108-4122, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38695833

RESUMEN

The K2CO3-mediated one-pot reaction of 1,3-acetonedicarboxylates with 2 equiv. of substituted 2-fluoro-1-nitrobenzenes has been developed to synthesize various 2,3-dicarboxylate indoles via a tandem annulation pathway. In the effective reaction, one carbon-carbon double bond, one carbon-carbon single bond and one carbon-nitrogen single bond are formed under open-vessel conditions. DFT calculations are used to rationalize the plausible mechanisms.

13.
Org Biomol Chem ; 22(27): 5561-5568, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38916128

RESUMEN

An organo-photoredox catalyzed gem-difluoroallylation of both acyclic and cyclic ketone derivatives with α-trifluoromethyl alkenes has been demonstrated, thus giving access to a diverse set of gem-difluoroalkenes in moderate to high yields. Pro-aromatic dihydroquinazolinones can be either pre-formed or in situ generated for ketone activation. This reaction is characterized by readily available starting materials, mild reaction conditions, and broad substrate scope. The feasibility of this reaction has been highlighted by the late-stage modification of several natural products and drug-like molecules as well as the in vitro antifungal activity.

14.
Acta Pharmacol Sin ; 45(4): 765-776, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38110583

RESUMEN

Hypertensive renal disease (HRD) contributes to the progression of kidney dysfunction and ultimately leads to end-stage renal disease. Understanding the mechanisms underlying HRD is critical for the development of therapeutic strategies. Deubiquitinating enzymes (DUBs) have been recently highlighted in renal pathophysiology. In this study, we investigated the role of a DUB, OTU Domain-Containing Protein 1 (OTUD1), in HRD models. HRD was induced in wild-type or Otud1 knockout mice by chronic infusion of angiotensin II (Ang II, 1 µg/kg per min) through a micro-osmotic pump for 4 weeks. We found that OTUD1 expression levels were significantly elevated in the kidney tissues of Ang II-treated mice. Otud1 knockout significantly ameliorated Ang II-induced HRD, whereas OTUD1 overexpression exacerbated Ang II-induced kidney damage and fibrosis. Similar results were observed in TCMK-1 cells but not in SV40 MES-13 cells following Ang II (1 µM) treatment. In Ang II-challenged TCMK-1 cells, we demonstrated that OTUD1 bound to CDK9 and induced CDK9 deubiquitination: OTUD1 catalyzed K63 deubiquitination on CDK9 with its Cys320 playing a critical role, promoting CDK9 phosphorylation and activation to induce inflammatory responses and fibrosis in kidney epithelial cells. Administration of a CDK9 inhibitor NVP-2 significantly ameliorated Ang II-induced HRD in mice. This study demonstrates that OTUD1 mediates HRD by targeting CDK9 in kidney epithelial cells, suggesting OTUD1 is a potential target in treating this disease.


Asunto(s)
Hipertensión Renal , Riñón , Nefritis , Proteasas Ubiquitina-Específicas , Animales , Ratones , Angiotensina II/metabolismo , Células Epiteliales/metabolismo , Fibrosis , Hipertensión Renal/enzimología , Hipertensión Renal/patología , Riñón/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Nefritis/enzimología , Nefritis/patología , Proteasas Ubiquitina-Específicas/metabolismo , Modelos Animales de Enfermedad
15.
J Clin Periodontol ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38986602

RESUMEN

AIM: To develop a nomogram-based predictive model of tooth survival by comprehensively analysing clinical and radiographic risk factors of tooth loss (TL). MATERIALS AND METHODS: In this study, 3447 teeth of 131 subjects who underwent non-surgical periodontal treatment were examined retrospectively within a mean follow-up period of 11.6 years. The association of risk factors including clinical and radiographic parameters with TL was assessed using univariate and multivariate Cox regression analyses. A nomogram-based predictive model was developed, and its validation and discriminatory ability were analysed. RESULTS: In all, 313 teeth were lost in 94 patients in this study (overall tooth loss [OTL] 9.08%; 0.21 teeth/patient/year). Male, heavy smoking, molar teeth, probing depth (PD), attachment loss (AL), tooth mobility and radiographic bone loss were significantly associated with TL (p < .05). A gradient effect of tooth mobility on TL increased from degree I to III versus none (p < .0001). The area under the curve (AUC) of the model was 0.865. Calibration curve and decision curve analysis demonstrated good performance and high net benefit, respectively. CONCLUSIONS: Adopting a specific nomogram could facilitate the prediction of tooth survival and the development of tailored treatment plans in Chinese patients with advanced periodontitis.

16.
BMC Musculoskelet Disord ; 25(1): 577, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39049000

RESUMEN

OBJECTIVE: To investigate (1) lateral atlantoaxial articulation (LAA) morphology in patients with basilar invagination (BI) with atlantoaxial dislocation (AAD) and healthy individuals and its relationship with the severity of dislocation and (2) the effect of the LAA morphology on reduction degree (RD) after surgery. METHODS: In this retrospective propensity score matching case-control study, imaging and baseline data of 62 patients with BI and AAD from 2011 to 2022 were collected. Six hundred thirteen  participants without occipitocervical junctional deformity served as controls. Logistic regression and receiver operating characteristic (ROC) curve were used for analysis. RESULTS: The age, BMI and sex did not differ significantly between the two groups after propensity score matching. Sagittal slope angle (SSA) and coronal slope angle (CSA) was lower and greater, respectively, in the patient group than in the control group. A negative SSA value usually indicates anteverted LAA. Regression analysis revealed a significant negative correlation between SSA and severity of dislocation. However, no relationship was found between CSA and the severity of dislocation. The multivariate logistic regression analysis revealed that minimum-SSA emerged as an independent predictor of satisfactory reduction (RD ≥ 90%). The ROC curve demonstrated an area under the curve of 0.844, with a cut-off value set at -40.2. CONCLUSION: SSA in patients group was significantly smaller and more asymmetric than that in the control group. Dislocation severity was related to SSA but not to CSA. Minimum-SSA can be used as a predictor of horizontal RD after surgery.


Asunto(s)
Articulación Atlantoaxoidea , Luxaciones Articulares , Humanos , Masculino , Femenino , Articulación Atlantoaxoidea/cirugía , Articulación Atlantoaxoidea/diagnóstico por imagen , Luxaciones Articulares/cirugía , Luxaciones Articulares/diagnóstico por imagen , Luxaciones Articulares/etiología , Estudios Retrospectivos , Adulto , Persona de Mediana Edad , Estudios de Casos y Controles , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Platibasia/diagnóstico por imagen , Platibasia/cirugía , Puntaje de Propensión , Adulto Joven , Fusión Vertebral/efectos adversos , Tomografía Computarizada por Rayos X
17.
Ecotoxicol Environ Saf ; 278: 116400, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38718725

RESUMEN

Evidence increasingly suggests molybdenum exposure at environmental levels is still associated with adverse human health, emphasizing the necessity to establish a more protective reference dose (RfD). Herein, we conducted a study measuring 15 urinary metals and 30 clinical health indicators in 2267 participants residing near chemical enterprises across 11 Chinese provinces to investigate their relationships. The kidney and cystatin-C emerged as the most sensitive organ and critical effect indicator of molybdenum exposure, respectively. Odds of cystatin-C-defined chronic kidney disease (CKD) in the highest quantile of molybdenum exposure significantly increased by 133.5% (odds ratio [OR]: 2.34, 95% CI: 1.78, 3.11) and 75.8% (OR: 1.76, 95% CI: 1.24, 2.49) before and after adjusting for urinary 14 metals, respectively. Intriguingly, cystatin-C significantly mediated 15.9-89.5% of molybdenum's impacts on liver and lung function, suggesting nephrotoxicity from molybdenum exposure may trigger hepatotoxicity and pulmonary toxicity. We derived a new RfD for molybdenum exposure (0.87 µg/kg-day) based on cystatin-C-defined estimated glomerular filtration rate by employing Bayesian Benchmark Dose modeling analysis. This RfD is significantly lower than current exposure guidance values (5-30 µg/kg-day). Remarkably, >90% of participants exceeded the new RfD, underscoring the significant health impacts of environmental molybdenum exposure on populations in industrial regions of China.


Asunto(s)
Molibdeno , Molibdeno/orina , Molibdeno/toxicidad , Molibdeno/análisis , Humanos , China/epidemiología , Femenino , Masculino , Adulto , Persona de Mediana Edad , Exposición a Riesgos Ambientales/estadística & datos numéricos , Exposición a Riesgos Ambientales/análisis , Cistatina C , Medición de Riesgo , Contaminantes Ambientales/orina , Contaminantes Ambientales/análisis , Adulto Joven , Teorema de Bayes , Insuficiencia Renal Crónica/epidemiología , Insuficiencia Renal Crónica/inducido químicamente , Anciano , Industria Química , Riñón/efectos de los fármacos , Tasa de Filtración Glomerular/efectos de los fármacos
18.
Sensors (Basel) ; 24(2)2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38257483

RESUMEN

With the continuous operation of analog circuits, the component degradation problem gradually comes to the forefront, which may lead to problems, such as circuit performance degradation, system stability reductions, and signal quality degradation, which could be particularly evident in increasingly complex electronic systems. At the same time, due to factors, such as continuous signal transformation, the fluctuation of component parameters, and the nonlinear characteristics of components, traditional fault localization methods are still facing significant challenges when dealing with large-scale complex circuit faults. Based on this, this paper proposes a fault-diagnosis method for analog circuits using the ECWGEO algorithm, an enhanced version of the GEO algorithm, to de-optimize the 1D-CNN with an attention mechanism to handle time-frequency fusion inputs. Firstly, a typical circuit-quad op-amp dual second-order filter circuit is selected to construct a fault-simulation model, and Monte Carlo analysis is used to obtain a large number of samples as the dataset of this study. Secondly, the 1D-CNN network structure is improved for the characteristics of the analog circuits themselves, and the time-frequency domain fusion input is implemented before inputting it into the network, while the attention mechanism is introduced into the network. Thirdly, instead of relying on traditional experience for network structure determination, this paper adopts a parameter-optimization algorithm for network structure optimization and improves the GEO algorithm according to the problem characteristics, which enhances the diversity of populations in the late stage of its search and accelerates the convergence speed. Finally, experiments are designed to compare the results in different dimensions, and the final proposed structure achieved a 98.93% classification accuracy, which is better than other methods.

19.
Molecules ; 29(5)2024 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-38474508

RESUMEN

The incorporation of amide groups into biologically active molecules has been proven to be an efficient strategy for drug design and discovery. In this study, we present a simple and practical method for the synthesis of amide-containing quinazolin-4(3H)-ones under transition-metal-free conditions. This is achieved through a carbamoyl-radical-triggered cascade cyclization of N3-alkenyl-tethered quinazolinones. Notably, the carbamoyl radical is generated in situ from the oxidative decarboxylative process of oxamic acids in the presence of (NH4)2S2O8.

20.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(3): 435-443, 2024 Jun.
Artículo en Zh | MEDLINE | ID: mdl-38953268

RESUMEN

With the continuous development of identification technologies such as mass spectrometry,omics,and antibody technology,post-translational modification (PTM) has demonstrated increasing potential in medical research.PTM as a novel chemical modification method provides new perspectives for the research on diseases.Succinylation as a novel modification has aroused the interest of more and more researchers.The available studies about succinylation mainly focus on a desuccinylase named sirtuin 5.This enzyme plays a key role in modification and has been preliminarily explored in cardiovascular studies.This paper summarizes the influencing factors and regulatory roles of succinylation and the links between succinylation and other PTMs and reviews the research progress of PTMs in the cardiovascular field,aiming to deepen the understanding about the role of this modification and give new insights to the research in this field.


Asunto(s)
Enfermedades Cardiovasculares , Lisina , Procesamiento Proteico-Postraduccional , Enfermedades Cardiovasculares/metabolismo , Humanos , Lisina/metabolismo , Ácido Succínico/metabolismo
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