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1.
BMC Cancer ; 24(1): 913, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39080593

RESUMO

BACKGROUND: In China, the national cervical cancer screening protocol involves initial testing for high-risk human papillomavirus (hrHPV), followed by cytology for hrHPV-positive cases. This study evaluates the effectiveness of PAX1 methylation (PAX1m) analysis in identifying precancerous or cancerous lesions in cervical samples from Chinese women positive for non-16/18 hrHPV strains. METHODS: Between February 2022 and March 2023, 281 cervical samples from non-16/18 hrHPV-positive women underwent cytological examination and PAX1m analysis. The study assessed the statistical relationship between PAX1m levels and the presence of cervical lesions, comparing the diagnostic performance of PAX1m to conventional cytology. RESULTS: A significant association was found between PAX1 methylation levels and the risk of CIN2 + and CIN3 + lesions, with 47 instances of CIN2 + detected. Odds ratios (ORs) for moderate and high PAX1m levels were 8.86 (95% CI: 2.24-42.17) and 166.32 (95% CI: 47.09-784.97), respectively. The area under the ROC curve for PAX1m in identifying CIN2 + lesions was 0.948 (95% CI: 0.895-0.99). PAX1m demonstrated similar sensitivity and negative predictive value (NPV) to cytology but reduced the colposcopy referral rate from 47.7% with cytology alone to 25.6% with PAX1m, showing superior specificity and positive predictive value across age groups. CONCLUSIONS: PAX1 methylation is a strong indicator of CIN2 + and CIN3 + risk, offering diagnostic performance comparable to cytology with the added benefit of reduced unnecessary colposcopy referrals. These findings support the use of PAX1m analysis as a reliable tool for triaging non-16/18 hrHPV-positive women in outpatient settings.


Assuntos
Metilação de DNA , Detecção Precoce de Câncer , Fatores de Transcrição Box Pareados , Infecções por Papillomavirus , Triagem , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/virologia , Neoplasias do Colo do Útero/genética , Pessoa de Meia-Idade , Detecção Precoce de Câncer/métodos , Adulto , Fatores de Transcrição Box Pareados/genética , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Triagem/métodos , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/virologia , Displasia do Colo do Útero/genética , China/epidemiologia , Idoso , Curva ROC , Biomarcadores Tumorais/genética , Esfregaço Vaginal
2.
BMC Gastroenterol ; 24(1): 240, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075402

RESUMO

PURPOSE: This study aimed to investigate clinical diagnostic values of mSEPT9 combined with NLR, PLR and LMR in CRC. METHODS: 329 subjects composed of 120 CRC patients, 105 polyps patients and 104 healthy participants were prospectively recruited. Clinicopathologic features were collected and analyzed. Plasma samples were collected for mSEPT9, NLR, PLR and LMR test. The sensitivity, specificity and AUC of each biomarker separately or in combination were estimated by the ROC curve. RESULTS: The levels of NLR, PLR and the PDR of mSEPT9 in CRC patients were significantly higher than those in non-CRC subjects, while LMR was the opposite. The PDR of mSEPT9 in CRC patients was significantly correlated with age, tumor size, tumor stage and M stage. ROC curve analysis demonstrated moderate diagnostic values of mSEPT9, NLR, PLR and LMR in CRC patients with AUC of 0.78 (Se = 0.68, and Sp = 0.89), 0.78 (Se = 0.68, and Sp = 0.83), 0.80 (Se = 0.68, and Sp = 0.81), and 0.77 (Se = 0.72, and Sp = 0.73), respectively. Moreover, combination of these four biomarkers dramatically enhanced the diagnostic accuracy of CRC (AUC = 0.92, Se = 0.90, and Sp = 0.87), especially for CRC patients with large tumors (AUC = 0.95) or distal metastasis (AUC = 0.95). CONCLUSION: mSEPT9, NLR, PLR and LMR showed the potential to be reliable biomarkers for the diagnosis of CRC. And the combined application of these biomarkers further improved the diagnostic accuracy of CRC significantly.


Assuntos
Biomarcadores Tumorais , Neoplasias Colorretais , Septinas , Humanos , Septinas/sangue , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Biomarcadores Tumorais/sangue , Sensibilidade e Especificidade , Curva ROC , Idoso , Estudos Prospectivos , Contagem de Plaquetas , Metilação de DNA , Adulto , Estudos de Casos e Controles , Neutrófilos , Estadiamento de Neoplasias , Plaquetas
3.
Nanotechnology ; 35(31)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38387100

RESUMO

As device feature sizes continue to decrease and fin field effect transistors reach their physical limits, gate all around field effect transistors (GAAFETs) have emerged with larger gate control areas and stackable characteristics for better suppression of second-order effects such as short-channel effects due to their gate encircling characteristics. Traditional methods for studying the electrical characteristics of devices are mostly based on the technology computer-aided design. Still, it is not conducive to developing new devices due to its time-consuming and inefficient drawbacks. Deep learning (DL) and machine learning (ML) have been well-used in recent years in many fields. In this paper, we propose an integrated learning model that integrates the advantages of DL and ML to solve many problems in traditional methods. This integrated learning model predicts the direct current characteristics, capacitance characteristics, and electrical parameters of GAAFET better than those predicted by DL or ML methods alone, with a linear regression factor (R2) greater than 0.99 and very small root mean square error. The proposed integrated learning model achieves fast and accurate prediction of GAAFET electrical characteristics, which provides a new idea for device and circuit simulation and characteristics prediction in microelectronics.

4.
Nature ; 554(7692): 387-391, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29414941

RESUMO

DNA methylation by de novo DNA methyltransferases 3A (DNMT3A) and 3B (DNMT3B) at cytosines is essential for genome regulation and development. Dysregulation of this process is implicated in various diseases, notably cancer. However, the mechanisms underlying DNMT3 substrate recognition and enzymatic specificity remain elusive. Here we report a 2.65-ångström crystal structure of the DNMT3A-DNMT3L-DNA complex in which two DNMT3A monomers simultaneously attack two cytosine-phosphate-guanine (CpG) dinucleotides, with the target sites separated by 14 base pairs within the same DNA duplex. The DNMT3A-DNA interaction involves a target recognition domain, a catalytic loop, and DNMT3A homodimeric interface. Arg836 of the target recognition domain makes crucial contacts with CpG, ensuring DNMT3A enzymatic preference towards CpG sites in cells. Haematological cancer-associated somatic mutations of the substrate-binding residues decrease DNMT3A activity, induce CpG hypomethylation, and promote transformation of haematopoietic cells. Together, our study reveals the mechanistic basis for DNMT3A-mediated DNA methylation and establishes its aetiological link to human disease.


Assuntos
DNA (Citosina-5-)-Metiltransferases/química , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , DNA/química , DNA/metabolismo , Sítios de Ligação , Proliferação de Células , Ilhas de CpG/genética , Cristalografia por Raios X , DNA/genética , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA/genética , DNA Metiltransferase 3A , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Neoplasias Hematológicas/enzimologia , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patologia , Humanos , Modelos Moleculares , Mutação , Ligação Proteica , Domínios Proteicos , Relação Estrutura-Atividade , Especificidade por Substrato
5.
J Opt Soc Am A Opt Image Sci Vis ; 41(6): 1044-1058, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856416

RESUMO

The performance analysis of a free space optical (FSO) communication system in the presence of random jamming is presented over a Málaga (M) distributed channel model with pointing errors and atmospheric attenuation. Firstly, the probability density function expressions of the transmission channel, signal-to-jamming ratio, and signal-to-noise ratio are derived. Then, considering the probability of the jammer and Gaussian white noise, the closed-form expressions for the ergodic channel capacity, outage probability, and average bit error rate are derived. Moreover, asymptotic expressions for the aforementioned performance metrics are also derived to ascertain the diversity gain of the system. Extensive Monte Carlo simulations are performed to demonstrate the credibility of this theoretical analysis. Results indicate that the adverse impact of random jamming is higher than that of Gaussian noise for the FSO communication system. Besides, this observation highlights the pulsating nature of the jamming effect, showcasing that within high signal-to-jamming ratio regions, a low probability jammer exerts the most significant impact on the FSO system.

6.
Curr Issues Mol Biol ; 45(4): 2861-2880, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37185711

RESUMO

The WRKY transcription factors are a class of transcriptional regulators that are ubiquitous in plants, wherein they play key roles in various physiological activities, including responses to stress. Specifically, WRKY transcription factors mediate plant responses to biotic and abiotic stresses through the binding of their conserved domain to the W-box element of the target gene promoter and the subsequent activation or inhibition of transcription (self-regulation or cross-regulation). In this review, the progress in the research on the regulatory effects of WRKY transcription factors on plant responses to external stresses is summarized, with a particular focus on the structural characteristics, classifications, biological functions, effects on plant secondary metabolism, regulatory networks, and other aspects of WRKY transcription factors. Future research and prospects in this field are also proposed.

7.
Curr Issues Mol Biol ; 45(3): 2035-2059, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36975501

RESUMO

CYCLOIDEA (CYC)-like genes belong to the TCP transcription factor family and play important roles associated with flower development. The CYC-like genes in the CYC1, CYC2, and CYC3 clades resulted from gene duplication events. The CYC2 clade includes the largest number of members that are crucial regulators of floral symmetry. To date, studies on CYC-like genes have mainly focused on plants with actinomorphic and zygomorphic flowers, including Fabaceae, Asteraceae, Scrophulariaceae, and Gesneriaceae species and the effects of CYC-like gene duplication events and diverse spatiotemporal expression patterns on flower development. The CYC-like genes generally affect petal morphological characteristics and stamen development, as well as stem and leaf growth, flower differentiation and development, and branching in most angiosperms. As the relevant research scope has expanded, studies have increasingly focused on the molecular mechanisms regulating CYC-like genes with different functions related to flower development and the phylogenetic relationships among these genes. We summarize the status of research on the CYC-like genes in angiosperms, such as the limited research conducted on CYC1 and CYC3 clade members, the necessity to functionally characterize the CYC-like genes in more plant groups, the need for investigation of the regulatory elements upstream of CYC-like genes, and exploration of the phylogenetic relationships and expression of CYC-like genes with new techniques and methods. This review provides theoretical guidance and ideas for future research on CYC-like genes.

8.
Inorg Chem ; 62(9): 3788-3798, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36814133

RESUMO

A new series of compounds, ANi5Bi5.6+δ (where A = K, Rb, and Cs) are discovered with a quasi-one-dimensional (Q1D) [Ni5Bi5.6+δ]- double-walled column and a coaxial inner one-dimensional Bi atomic chain. The columns are linked to each other by intercolumn Bi-Bi bonds and separated by an A+ cation. Typical metallic behaviors with strong correlation of itinerant electrons and the Sommerfeld coefficient enhanced with the increasing cationic radius were experimentally observed and supported by first-principles calculations. Compared to AMn6Bi5 (where A = K, Rb, and Cs), the enhanced intercolumn distances and the substitution of Ni for Mn give rise to strong diamagnetic susceptibilities in ANi5Bi5.6+δ. First-principles calculations reveal possible uncharged Ni atoms with even number of electrons in ANi5Bi5.6+δ, which may explain the emergence of diamagnetism. ANi5Bi5.6+δ, as Q1D diamagnetic metals with strong electron correlation, provide a unique platform to understand exotic magnetism and explore novel quantum effects.

9.
J Gastroenterol Hepatol ; 38(7): 1181-1191, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37078141

RESUMO

BACKGROUND AND AIM: Tumor progression and distant metastasis are the main causes of deaths in gastric cancer. Growing evidence revealed that circular RNAs (circRNAs) play critical role in the pathology of malignant disease, the role of circRNAs in gastric cancer progression and metastasis is still unknown. METHODS: Differentially expressed circRNAs was identified by circRNA microarray and validated by quantitative reverse transcription polymerase reaction. The biological function of circTNIK was evaluated by in vitro and in vivo experiments after ectopic expression or siRNA mediated knockdown of circTNIK. The interaction between circTNIK and miR-138-5p was determined by luciferase activity assay, RNA immunoprecipitation, and fluorescence in situ hybridization assays. RESULTS: circTNIK rather than linear TINK mRNA was significantly upregulated in gastric cancer tissues, cell lines compared with normal controls. Higher circTNIK expression was correlated with aggressive tumor phenotypes and poor overall survival in gastric cancer patients. Ectopic circTNIK expression promoted cell proliferation, invasion, tumorigenesis, and metastasis in gastric cancer cells whereas knockdown of circTNIK inhibited cell proliferation, invasion, tumorigenesis, and metastasis in gastric cancer cells. Importantly, circTNIK functions as a molecular sponge for miR-138-5p to regulate the expression of ZEB2. CONCLUSIONS: Overall, our study demonstrates how circTNIK regulates gastric cancer progression and metastasis by sponging miR-138-5p to modulate the expression of ZEB2. CircTNIK might be used as a prognostic biomarker in gastric cancer patients.


Assuntos
MicroRNAs , Neoplasias Gástricas , Humanos , RNA Circular/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Gástricas/patologia , Hibridização in Situ Fluorescente , Linhagem Celular Tumoral , Carcinogênese/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Movimento Celular , Homeobox 2 de Ligação a E-box com Dedos de Zinco/genética , Homeobox 2 de Ligação a E-box com Dedos de Zinco/metabolismo
10.
Planta ; 257(1): 7, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36478305

RESUMO

MAIN CONCLUSION: The predominant flavones in the ray florets of chrysanthemum flowers are apigenin and its derivatives. CmHY5 participates in apigenin biosynthesis by directly regulating the expression of FNSII-1 in chrysanthemum. Chrysanthemum (Chrysanthemum morifolium) flowers have been used for centuries as functional food and in herbal tea and traditional medicine. The chrysanthemum flower contains significant amounts of the biologically active compound flavones, which has medicinal properties. However, the mechanism regulating flavones biosynthesis in chrysanthemum flowers organs is still unclear. Here, we compared the transcriptomes and metabolomes of different floral organs between two cultivars with contrasting flavone levels in their flowers. We identified 186 flavonoids by metabolome analysis. The predominant flavones in the ray florets of chrysanthemum flowers are apigenin and its derivatives, of which the contents are highly correlated with the expression of flavones synthase II gene CmFNSII-1. We also determined that CmHY5 is a direct upstream regulator of CmFNSII-1 transcription. We showed that CmHY5 RNAi interference lines in chrysanthemum have lower contents of apigenin compared to wild-type chrysanthemum. Our results demonstrated that CmHY5 participates in flavone biosynthesis by directly regulating the expression of FNSII-1 in chrysanthemum.


Assuntos
Apigenina , Medicina Tradicional
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