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1.
Front Endocrinol (Lausanne) ; 15: 1433192, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39224123

RESUMEN

Introduction: The detection rate of benign thyroid nodules is increasing every year, with some affected patients experiencing symptoms. Ultrasound-guided thermal ablation can reduce the volume of nodules to alleviate symptoms. As the degree and speed of lesion absorption vary greatly between individuals, an effective model to predict curative effect after ablation is lacking. This study aims to predict the efficacy of ultrasound-guided thermal ablation for benign thyroid nodules using machine learning and explain the characteristics affecting the nodule volume reduction ratio (VRR). Design: Prospective study. Patients: The clinical and ultrasonic characteristics of patients who underwent ultrasound-guided thermal ablation of benign thyroid nodules at our hospital between January 2020 and January 2023 were recorded. Measurements: Six machine learning models (logistic regression, support vector machine, decision tree, random forest, eXtreme Gradient Boosting [XGBoost], and Light Gradient Boosting Machine [LGBM]) were constructed to predict efficacy; the effectiveness of each model was evaluated, and the optimal model selected. SHapley Additive exPlanations (SHAP) was used to visualize the decision process of the optimal model and analyze the characteristics affecting the VRR. Results: In total, 518 benign thyroid nodules were included: 356 in the satisfactory group (VRR ≥70% 1 year after operation) and 162 in the unsatisfactory group. The optimal XGBoost model predicted satisfactory efficacy with 78.9% accuracy, 88.8% precision, 79.8% recall rate, an F1 value of 0.84 F1, and an area under the curve of 0.86. The top five characteristics that affected VRRs were the proportion of solid components < 20%, initial nodule volume, blood flow score, peripheral blood flow pattern, and proportion of solid components 50-80%. Conclusions: The models, based on interpretable machine learning, predicted the VRR after thermal ablation for benign thyroid nodules, which provided a reference for preoperative treatment decisions.


Asunto(s)
Aprendizaje Automático , Nódulo Tiroideo , Humanos , Nódulo Tiroideo/cirugía , Nódulo Tiroideo/patología , Nódulo Tiroideo/diagnóstico por imagen , Femenino , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Adulto , Resultado del Tratamiento , Ultrasonografía Intervencional/métodos
2.
Funct Integr Genomics ; 24(5): 158, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39249547

RESUMEN

Long non-coding RNAs (lncRNAs) regulate the occurrence, development and progression of oral squamous cell carcinoma (OSCC). We elucidated the expression features of MAGEA4-AS1 in patients with OSCC and its activity as an OSCC biomarker. Furthermore, the impact of up-regulation of MAGEA4-AS1 on the cellular behaviors (proliferation, migration and invasion) of OSCC cells and intrinsic signal mechanisms were evaluated. Firstly, we analyzed MAGEA4-AS1 expression data in The Cancer Genome Atlas (TCGA) OSCC using a bioinformatics approach and in 45 pairs of OSCC tissues using qPCR. Then CCK-8, ethynyl deoxyuridine, colony formation, transwell and wound healing assays were conducted to assess changes in the cell proliferation, migration and invasion protential of shMAGEA4-AS1 HSC3 and CAL27 cells. The RNA sequence of MAGEA4-AS1 was identified using the rapid amplification of cDNA ends (RACE) assay. And whole-transcriptome sequencing was used to identify MAGEA4-AS1 affected genes. Additionally, dual-luciferase reporter system, RNA-binding protein immunoprecipitation (RIP), and rescue experiments were performed to clarify the role of the MAGEA4-AS1-p53-MK2 signaling pathway. As results, we found MAGEA4-AS1 was up-regulated in OSCC tissues. We identified a 418 nucleotides length of the MAGEA4-AS1 transcript and it primarily located in the cell nucleus. MAGEA4-AS1 stable knockdown weakened the proliferation, migration and invasion abilities of OSCC cells. Mechanistically, p53 protein was capable to activate MK2 gene transcription. RIP assay revealed an interaction between p53 and MAGEA4-AS1. MK2 up-regulation in MAGEA4-AS1 down-regulated OSCC cells restored MK2 and epithelial-to-mesenchymal transition related proteins' expression levels. In conclusion, MAGEA4-AS1-p53 complexes bind to MK2 promoter, enhancing the transcription of MK2 and activating the downstream signaling pathways, consequently promoting the proliferation and metastasis of OSCC cells. MAGEA4-AS1 may serve as a diagnostic marker and therapeutic target for OSCC patients.


Asunto(s)
Movimiento Celular , Proliferación Celular , Péptidos y Proteínas de Señalización Intracelular , Neoplasias de la Boca , Proteínas Serina-Treonina Quinasas , ARN Largo no Codificante , Transducción de Señal , Proteína p53 Supresora de Tumor , Humanos , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Neoplasias de la Boca/genética , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Línea Celular Tumoral , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Regulación Neoplásica de la Expresión Génica , Femenino , Masculino , Metástasis de la Neoplasia
3.
Artículo en Inglés | MEDLINE | ID: mdl-39088025

RESUMEN

This study aimed to develop a multienzymatic system for synthesis of L-malate. First, recombinant Escherichia coli strains were constructed expressing maleic acid cis-trans isomerase (MaiA) or fumarase C (FumC) from different sources. Serratia marcescens MaiA (SMaiA) and E. coli FumC (ECFumC) showed good catalytic performance. Next, six co-expression systems for SMaiA and ECFumC were constructed. E. coli BL21 (DE3)-pRSFDuet-1-ecfumC-smaiA (named strain pFM2) had the highest L-malate catalytic activity. In 7-L fed-batch fermentation, the SMaiA and ECFumC activities of strain pFM2 wet cells were 43.4 and 154.5 U/g, respectively, 2.4- and 10.7-fold the values that were obtained in shaken flasks. Finally, a whole-cell catalytic process was established for the production of L-malate by strain pFM2 with maleate as the substrate. When the dose of pFM2 wet cells was 0.5 g/100 mL and 1 mol/L maleate was the substrate, the catalytic process was completed within 4 h. Notably, the intermediate fumarate was almost absent during the conversion process. The concentration of L-malate reached 143.8 g/L with a yield of 0.60 g/(L·min). The molar conversion rate of the substrate was 98.4%. These findings lay a foundation for the industrial application of multienzymatic synthesis of L-malate.

4.
Antimicrob Agents Chemother ; : e0017624, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39194263

RESUMEN

Protein arginine methyltransferases (PRMTs) play critical roles in Plasmodium falciparum, a protozoan causing the deadliest form of malaria, making them potential targets for novel antimalarial drugs. Here, we screened 11 novel PRMT inhibitors against P. falciparum asexual growth and found that onametostat, an inhibitor for type II PRMTs, exhibited strong antimalarial activity with a half-maximal inhibitory concentration (IC50) value of 1.69 ± 0.04 µM. In vitro methyltransferase activities of purified PfPRMT5 were inhibited by onametostat, and a shift of IC50 to onametostat was found in the PfPRTM5 disruptant parasite line, indicating that PfPRTM5 is the primary target of onametostat. Consistent with the function of PfPRMT5 in mediating symmetric dimethylation of histone H3R2 (H3R2me2s) and in regulating invasion-related genes, onametostat treatment led to the reduction of H3R2me2s level in P. falciparum and caused the defects on the parasite's invasion of red blood cells. This study provides a starting point for identifying specific PRMT inhibitors with the potential to serve as novel antimalarial drugs.

5.
Nat Commun ; 15(1): 3747, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702310

RESUMEN

In malaria parasites, the regulation of mRNA translation, storage and degradation during development and life-stage transitions remains largely unknown. Here, we functionally characterized the DEAD-box RNA helicase PfDOZI in P. falciparum. Disruption of pfdozi enhanced asexual proliferation but reduced sexual commitment and impaired gametocyte development. By quantitative transcriptomics, we show that PfDOZI is involved in the regulation of invasion-related genes and sexual stage-specific genes during different developmental stages. PfDOZI predominantly participates in processing body-like mRNPs in schizonts but germ cell granule-like mRNPs in gametocytes to impose opposing actions of degradation and protection on different mRNA targets. We further show the formation of stress granule-like mRNPs during nutritional deprivation, highlighting an essential role of PfDOZI-associated mRNPs in stress response. We demonstrate that PfDOZI participates in distinct mRNPs to maintain mRNA homeostasis in response to life-stage transition and environmental changes by differentially executing post-transcriptional regulation on the target mRNAs.


Asunto(s)
ARN Helicasas DEAD-box , Plasmodium falciparum , Proteínas Protozoarias , ARN Mensajero , ARN Helicasas DEAD-box/metabolismo , ARN Helicasas DEAD-box/genética , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Plasmodium falciparum/crecimiento & desarrollo , ARN Mensajero/metabolismo , ARN Mensajero/genética , Proteínas Protozoarias/metabolismo , Proteínas Protozoarias/genética , Ribonucleoproteínas/metabolismo , Ribonucleoproteínas/genética , Estadios del Ciclo de Vida/genética , ARN Protozoario/metabolismo , ARN Protozoario/genética , Estabilidad del ARN , Humanos , Malaria Falciparum/parasitología
6.
iScience ; 27(4): 109602, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38617559

RESUMEN

It is a significant challenge to assess the functions of many uncharacterized genes in human malaria parasites. Here, we present a genetic screening tool to assess the contribution of essential genes from Plasmodium falciparum by the conditional CRISPR-/deadCas9-based interference and activation (i/a) systems. We screened both CRISPRi and CRISPRa sets, consisting of nine parasite lines per set targeting nine genes via their respective gRNAs. By conducting amplicon sequencing of gRNA loci, we identified the contribution of each targeted gene to parasite fitness upon drug (artemisinin, chloroquine) and stress (starvation, heat shock) treatment. The screening was highly reproducible, and the screening libraries were easily generated by transfection of mixed plasmids expressing different gRNAs. We demonstrated that this screening is straightforward, robust, and can provide a fast and efficient tool to study essential genes that have long presented a bottleneck in assessing their functions using existing genetic tools.

7.
mSphere ; 9(4): e0014024, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38564734

RESUMEN

Histone lysine acetyltransferase MYST-associated NuA4 complex is conserved from yeast to humans and plays key roles in cell cycle regulation, gene transcription, and DNA replication/repair. Here, we identified a Plasmodium falciparum MYST-associated complex, PfNuA4, which contains 11 of the 13 conserved NuA4 subunits. Reciprocal pulldowns using PfEAF2, a shared component between the NuA4 and SWR1 complexes, not only confirmed the PfNuA4 complex but also identified the PfSWR1 complex, a histone remodeling complex, although their identities are low compared to the homologs in yeast or humans. Notably, both H2A.Z/H2B.Z were associated with the PfSWR1 complex, indicating that this complex is involved in the deposition of H2A.Z/H2B.Z, the variant histone pair that is enriched in the activated promoters. Overexpression of PfMYST resulted in earlier expression of genes involved in cell cycle regulation, DNA replication, and merozoite invasion, and upregulation of the genes related to antigenic variation and DNA repair. Consistently, PfMYST overexpression led to high basal phosphorylated PfH2A (γ-PfH2A), the mark of DNA double-strand breaks, and conferred protection against genotoxic agent methyl methanesulfonate (MMS), X-rays, and artemisinin, the first-line antimalarial drug. In contrast, the knockdown of PfMYST caused a delayed parasite recovery upon MMS treatment. MMS induced the gradual disappearance of PfMYST in the cytoplasm and concomitant accumulation of PfMYST in the nucleus, suggesting cytoplasm-nucleus shuttling of PfMYST. Meanwhile, PfMYST colocalized with the γ-PfH2A, indicating PfMYST was recruited to the DNA damage sites. Collectively, PfMYST plays critical roles in cell cycle regulation, gene transcription, and DNA replication/DNA repair in this low-branching parasitic protist.IMPORTANCEUnderstanding gene regulation and DNA repair in malaria parasites is critical for identifying targets for antimalarials. This study found PfNuA4, a PfMYST-associated, histone modifier complex, and PfSWR1, a chromatin remodeling complex in malaria parasite Plasmodium falciparum. These complexes are divergent due to the low identities compared to their homologs from yeast and humans. Furthermore, overexpression of PfMYST resulted in substantial transcriptomic changes, indicating that PfMYST is involved in regulating the cell cycle, antigenic variation, and DNA replication/repair. Consistently, PfMYST was found to protect against DNA damage caused by the genotoxic agent methyl methanesulfonate, X-rays, and artemisinin, the first-line antimalarial drug. Additionally, DNA damage led to the relocation of cytoplasmic PfMYST to the nucleus and colocalization of PfMYST with γ-PfH2A, the mark of DNA damage. In summary, this study demonstrated that the PfMYST complex has critical functions in regulating cell cycle, antigenic variation, and DNA replication/DNA repair in P. falciparum.


Asunto(s)
Reparación del ADN , Plasmodium falciparum , Proteínas Protozoarias , Plasmodium falciparum/genética , Plasmodium falciparum/efectos de los fármacos , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Histona Acetiltransferasas/genética , Histona Acetiltransferasas/metabolismo , Humanos , Replicación del ADN , Histonas/genética , Histonas/metabolismo , Regulación de la Expresión Génica
8.
Biomolecules ; 14(2)2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38397460

RESUMEN

MicroRNAs (miRNAs) in oral squamous cell carcinoma (OSCC)-derived small extracellular vesicles (sEVs) play a pivotal role in modulating intercellular communications between tumor cells and other cells in the microenvironment, thereby influencing tumor progression and the efficacy of therapeutic interventions. However, a comprehensive inventory of these secretory miRNAs in sEVs and their biological and clinical implications remains elusive. This study aims to profile the miRNA content of OSCC cell line sEVs and computationally elucidate their biological and clinical relevance. We conducted miRNA sequencing to compare the miRNA profiles of OSCC cells and their corresponding sEVs. Our motif enrichment analysis identified specific sorting motifs that are implicated in either cellular retention or preferential sEV secretion. Target cell analysis suggested that the sEV miRNAs potentially interact with various immune cell types, including natural killer cells and dendritic cells. Additionally, we explored the clinical relevance of these miRNAs by correlating their expression levels with TNM stages and patient survival outcomes. Intriguingly, our findings revealed that a distinct sEV miRNA signature is associated with lymph node metastasis and poorer survival in patients in TCGA-HNSC dataset. Collectively, this research furthers our understanding of the miRNA sorting mechanisms in OSCC and underscores their clinical implications.


Asunto(s)
Carcinoma de Células Escamosas , Vesículas Extracelulares , Neoplasias de Cabeza y Cuello , MicroARNs , Neoplasias de la Boca , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello , Carcinoma de Células Escamosas/patología , Metástasis Linfática , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Línea Celular Tumoral , Vesículas Extracelulares/metabolismo , Microambiente Tumoral
9.
Antimicrob Agents Chemother ; 67(10): e0057723, 2023 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-37702516

RESUMEN

Plasmodium falciparum causes the most severe malaria and is exposed to various environmental and physiological stresses in the human host. Given that GCN5 plays a critical role in regulating stress responses in model organisms, we aimed to elucidate PfGCN5's function in stress responses in P. falciparum. The protein level of PfGCN5 was substantially induced under three stress conditions [heat shock, low glucose starvation, and dihydroartemisinin, the active metabolite of artemisinin (ART)]. With a TetR-DOZI conditional knockdown (KD) system, we successfully down-regulated PfGCN5 to ~50% and found that KD parasites became more sensitive to all three stress conditions. Transcriptomic analysis via RNA-seq identified ~1,000 up- and down-regulated genes in the wild-type (WT) and KD parasites under these stress conditions. Importantly, DHA induced transcriptional alteration of many genes involved in many aspects of stress responses, which were heavily shared among the altered genes under heat shock and low glucose conditions, including ART-resistance-related genes such as K13 and coronin. Based on the expression pattern between WT and KD parasites under three stress conditions, ~300-400 genes were identified to be involved in PfGCN5-dependent, general, and stress-condition-specific responses with high levels of overlaps among three stress conditions. Notably, using ring-stage survival assay, we found that KD or inhibition of PfGCN5 could sensitize the ART-resistant parasites to the DHA treatment. All these indicate that PfGCN5 is pivotal in regulating general and ART-resistance-related stress responses in malaria parasites, implicating PfGCN5 as a potential target for malaria intervention.


Asunto(s)
Antimaláricos , Artemisininas , Malaria Falciparum , Humanos , Plasmodium falciparum/metabolismo , Artemisininas/farmacología , Artemisininas/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Glucosa/metabolismo , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Resistencia a Medicamentos/genética
10.
Math Biosci Eng ; 20(6): 10027-10042, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-37322922

RESUMEN

How to ensure the smooth implementation of convergent infrastructure engineering as the risk of sudden public events persists, allowing the engineering supply chain companies to break through the blockages to regenerate collaboratively and form a regenerated collaborative union. By establishing a mathematical game model, this paper explores the synergistic mechanism of supply chain regeneration for convergent infrastructure engineering, which takes into account cooperation and competition, investigates the impact of supply chain nodes' regeneration capacity and economic performance, as well as the dynamic changes in the importance weights of supply chain nodes, when adopting the collaborative decision of supply chain regeneration, the benefits of the supply chain system, are more than those when suppliers and manufacturers "act of one's own free will" by making decentralized decisions to undertake supply chain regeneration separately. All the investment costs of supply chain regeneration are higher than those in non-cooperative games. Based on the comparison of equilibrium solutions, it was found that exploring the collaborative mechanism of its convergence infrastructure engineering supply chain regeneration provides useful arguments for the emergency re-engineering of the engineering supply chain with a tube mathematical basis. Through constructing a dynamic game model for the exploration of the supply chain regeneration synergy mechanism, this paper provides methods and support for the emergency synergy among subjects of infrastructure construction projects, especially in improving the mobilization effectiveness of the entire infrastructure construction supply chain in critical emergencies and enhancing the emergency re-engineering capability of the supply chain.


Asunto(s)
Toma de Decisiones , Modelos Teóricos , Humanos , Costos y Análisis de Costo , Ingeniería
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