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1.
Plant Cell ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39167833

RESUMEN

Autoluminescent plants have been genetically modified to express the fungal bioluminescence pathway (FBP). However, a bottleneck in precursor production has limited the brightness of these luminescent plants. Here, we demonstrate the effectiveness of utilizing a computational model to guide a multiplex five-gene-silencing strategy by an artificial microRNA array to enhance caffeic acid and hispidin levels in plants. By combining loss-of-function-directed metabolic flux with a tyrosine-derived caffeic acid pathway, we achieved substantially enhanced bioluminescence levels. We successfully generated eFBP2 plants that emit considerably brighter bioluminescence for naked-eye reading by integrating all validated DNA modules. Our analysis revealed that the luminous energy conversion efficiency of the eFBP2 plants is currently very low, suggesting that luminescence intensity can be improved in future iterations. These findings highlight the potential to enhance plant luminescence through the integration of biological and information technologies.

2.
Nucleic Acids Res ; 52(15): 9303-9316, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39036959

RESUMEN

Targeting inter-duplex junctions in catenated DNA with bidirectional bis-intercalators is a potential strategy for enhancing anticancer effects. In this study, we used d(CGTATACG)2, which forms a tetraplex base-pair junction that resembles the DNA-DNA contact structure, as a model target for two alkyl-linked diaminoacridine bis-intercalators, DA4 and DA5. Cross-linking of the junction site by the bis-intercalators induced substantial structural changes in the DNA, transforming it from a B-form helical end-to-end junction to an over-wounded side-by-side inter-duplex conformation with A-DNA characteristics and curvature. These structural perturbations facilitated the angled intercalation of DA4 and DA5 with propeller geometry into two adjacent duplexes. The addition of a single carbon to the DA5 linker caused a bend that aligned its chromophores with CpG sites, enabling continuous stacking and specific water-mediated interactions at the inter-duplex contacts. Furthermore, we have shown that the different topological changes induced by DA4 and DA5 lead to the inhibition of topoisomerase 2 activities, which may account for their antitumor effects. Thus, this study lays the foundations for bis-intercalators targeting biologically relevant DNA-DNA contact structures for anticancer drug development.


Asunto(s)
Antineoplásicos , ADN , Sustancias Intercalantes , Conformación de Ácido Nucleico , Sustancias Intercalantes/química , Sustancias Intercalantes/farmacología , Antineoplásicos/farmacología , Antineoplásicos/química , Humanos , ADN/química , ADN/metabolismo , ADN-Topoisomerasas de Tipo II/metabolismo , ADN-Topoisomerasas de Tipo II/química , Línea Celular Tumoral , Inhibidores de Topoisomerasa II/química , Inhibidores de Topoisomerasa II/farmacología
3.
Plant Physiol ; 195(3): 1835-1850, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38535832

RESUMEN

Plant transporters regulating the distribution of secondary metabolites play critical roles in defending against pathogens, insects, and interacting with beneficial microbes. The phosphorylation of these transporters can alter their activity, stability, and intracellular protein trafficking. However, the regulatory mechanism underlying this modification remains elusive. In this study, we discovered two orthologs of mammalian PKA, PKG, and PKC (AGC) kinases, oxidative signal-inducible 1 (OXI1) and its closest homologue, AGC subclass 2 member 2 (AGC2-2; 75% amino acid sequence identity with OXI1), associated with the extracellular secretion of camalexin and Arabidopsis (Arabidopsis thaliana) resistance to Pseudomonas syringae, and Botrytis cinerea. These kinases can undergo in vitro kinase reactions with three pleiotropic drug resistance (PDR) transporters: PDR6, PDR8, and PDR12. Moreover, our investigation confirmed PDR6 interaction with OXI1 and AGC2-2. By performing LC-MS/MS and parallel reaction monitoring, we identified the phosphorylation sites on PDR6 targeted by these kinases. Notably, chitin-induced PDR6 phosphorylation at specific residues, namely S31, S33, S827, and T832. Additional insights emerged by expressing dephosphorylated PDR6 variants in a pdr6 mutant background, revealing that the target residues S31, S33, and S827 promote PDR6 efflux activity, while T832 potentially contributes to PDR6 stability within the plasma membrane. The findings of this study elucidate partial mechanisms involved in the activity regulation of PDR-type transporters, providing valuable insights for their potential application in future plant breeding endeavors.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Botrytis , Resistencia a la Enfermedad , Enfermedades de las Plantas , Pseudomonas syringae , Tiazoles , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Botrytis/fisiología , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Indoles/metabolismo , Fosforilación , Fitoalexinas , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Proteínas Quinasas/metabolismo , Proteínas Quinasas/genética , Pseudomonas syringae/patogenicidad , Pseudomonas syringae/fisiología , Tiazoles/metabolismo
4.
Mol Psychiatry ; 29(7): 2031-2042, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38361125

RESUMEN

Running exercise has been shown to alleviate depressive symptoms. However, the mechanism underlying the antidepressant effects of running exercise is not fully understood. The imbalance of M1/M2 microglia phenotype/polarization and concomitant dysregulation of neuroinflammation play crucial roles in the pathogenesis of depression. Running exercise increases circulating levels of adiponectin which is known to cross the blood‒brain barrier and suppress inflammatory responses. AdipoR1 is an adiponectin receptor that is involved in regulating microglial phenotypes and activation states. However, whether running exercise regulates hippocampal microglial phenotypes and neuroinflammation through adiponectin/AdipoR1 to exert its antidepressant effects remains unclear. In the current study, 4 weeks of running exercise significantly alleviated the depressive-like behaviors of chronic unpredictable stress (CUS)-exposed mice. Moreover, running exercise decreased the microglial numbers and altered microglial morphology in three subregions of the hippocampus to restore the M1/M2 balance; these effects were accompanied by regulation of pro-/anti-inflammatory cytokine production and secretion in CUS-exposed mice. These effects may involve elevation of peripheral tissue (adipose tissue and muscle) and plasma adiponectin levels, and hippocampal AdipoR1 levels as well as activation of the AMPK-NF-κB/STAT3 signaling pathway by running exercise. When an adeno-associated virus was used to knock down hippocampal AdipoR1, mice showed depressive-like behaviors and alterations in microglia and inflammatory factor expression in the hippocampus that were similar to those observed in CUS-exposed mice. Together, these results suggest that running exercise maintains the M1/M2 balance and inhibits neuroinflammation in the hippocampus of CUS-exposed mice. These effects might occur via adiponectin/AdipoR1-mediated activation of the AMPK-NF-κB/STAT3 signaling pathway.


Asunto(s)
Adiponectina , Depresión , Hipocampo , Microglía , Enfermedades Neuroinflamatorias , Condicionamiento Físico Animal , Receptores de Adiponectina , Transducción de Señal , Estrés Psicológico , Animales , Microglía/metabolismo , Hipocampo/metabolismo , Adiponectina/metabolismo , Ratones , Estrés Psicológico/metabolismo , Estrés Psicológico/terapia , Receptores de Adiponectina/metabolismo , Condicionamiento Físico Animal/métodos , Condicionamiento Físico Animal/fisiología , Masculino , Transducción de Señal/fisiología , Depresión/metabolismo , Depresión/terapia , Enfermedades Neuroinflamatorias/metabolismo , Carrera/fisiología , Ratones Endogámicos C57BL , Inflamación/metabolismo , Modelos Animales de Enfermedad , Citocinas/metabolismo , FN-kappa B/metabolismo , Factor de Transcripción STAT3/metabolismo
5.
Nano Lett ; 24(10): 3221-3230, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38416582

RESUMEN

The hydrolysis of hydrides, represented by MgH2, delivers substantial capacity and presents an appealing prospect for an on-site hydrogen supply. However, the sluggish hydrolysis kinetics and low hydrogen yield of MgH2 caused by the formation of a passivation Mg(OH)2 layer hinder its practical application. Herein, we present a dual strategy encompassing microstructural design and compounding, leading to the successful synthesis of a core-shell-like nanostructured MgH2@Mg(BH4)2 composite, which demonstrates excellent hydrolysis performance. Specifically, the optimal composite with a low Ea of 9.05 kJ mol-1 releases 2027.7 mL g-1 H2 in 60 min, and its hydrolysis rate escalates to 1356.7 mL g-1 min-1 H2 during the first minute at room temperature. The nanocoating Mg(BH4)2 plays a key role in enhancing the hydrolysis kinetics through the release of heat and the formation of local concentration of Mg2+ field after its hydrolysis. This work offers an innovative concept for the design of hydrolysis materials.

6.
J Biol Chem ; 299(7): 104864, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37245780

RESUMEN

Secondary structures formed by expanded CUG RNA are involved in the pathobiology of myotonic dystrophy type 1. Understanding the molecular basis of toxic RNA structures can provide insights into the mechanism of disease pathogenesis and accelerate the drug discovery process. Here, we report the crystal structure of CUG repeat RNA containing three U-U mismatches between C-G and G-C base pairs. The CUG RNA crystallizes as an A-form duplex, with the first and third U-U mismatches adopting a water-mediated asymmetric mirror isoform geometry. We found for the first time that a symmetric, water-bridged U-H2O-U mismatch is well tolerated within the CUG RNA duplex, which was previously suspected but not observed. The new water-bridged U-U mismatch resulted in high base-pair opening and single-sided cross-strand stacking interactions, which in turn dominate the CUG RNA structure. Furthermore, we performed molecular dynamics simulations that complemented the structural findings and proposed that the first and third U-U mismatches are interchangeable conformations, while the central water-bridged U-U mismatch represents an intermediate state that modulates the RNA duplex conformation. Collectively, the new structural features provided in this work are important for understanding the recognition of U-U mismatches in CUG repeats by external ligands such as proteins or small molecules.


Asunto(s)
Distrofia Miotónica , Humanos , Distrofia Miotónica/genética , Agua/química , ARN/metabolismo , Emparejamiento Base , Conformación de Ácido Nucleico
7.
Small ; : e2406448, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39279302

RESUMEN

Designing nano-electrocatalysts rich in surface defects is critical to improve their catalytic performance. However, prevailing synthesis techniques rely heavily on complex procedures that compromise defect extensiveness and uniformity, casting a high demand for methods capable of synthesizing large-scale crystalline defects. An innovative design strategy is herein proposed that induces ample strain/dislocation defects during the growth of palladium (Pd), which is well-known as a good oxygen reduction reaction (ORR) catalyst. The controlled defect engineering on Pd core is achieved by the tensile stress exerted from an intentionally applied Fe3O4 skin layer during synthesis, which changes the surface free energy of Pd to stabilize the defect presence. With such large-scale crystalline defects, this Pd catalyst exhibits significantly higher ORR activity than commercial Pt/C, enabling its promising future in zinc-air battery catalysis. Additionally, the protective Fe3O4 skin covering the catalyst also enhances its catalytic stability. Theoretical calculations show that the superior catalytic property of such defect-engineered Pd is associated with the correspondingly modified adsorption energy of *O intermediates onto its surface, which further improves the reaction rate and thus boosts ORR kinetics. Findings here are expected to provide a paradigm for designing efficient and stable metal catalysts with plentiful large-scale strain defects.

8.
Small ; 20(35): e2310037, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38634208

RESUMEN

Highly concentrated "'water-in-salt"' (WIS) electrolytes are promising for high-performance energy storage devices due to their wide electrochemical stability window. However, the energy storage mechanism of MnO2 in WIS electrolytes-based supercapacitors remains unclear. Herein, MnO2 nanoflowers are successfully grown on mesoporous bowl-like carbon (MBC) particles to generate MnO2/MBC composites, which not only increase electroactive sites and inhibit the pulverization of MnO2 particles during the fast charging/discharging processes, but also facilitate the electron transfer and ion diffusion within the whole electrode, resulting in significant enhancement of the electrochemical performance. An asymmetric supercapacitor, assembled with MnO2/MBC and activated carbon (AC) and using 21 m LiTFSI solution as the WIS electrolyte, delivers an ultrahigh energy density of 70.2 Wh kg-1 at 700 W kg-1, and still retains 24.8 Wh kg-1 when the power density is increased to 28 kW kg-1. The ex situ XRD, Raman, and XPS measurements reveal that a reversible reaction of MnO2 + xLi+ + xe-↔LixMnO2 takes place during charging and discharging. Therefore, the asymmetric MnO2/MBC//AC supercapacitor with LiTFSI electrolyte is actually a lithium-ion hybrid supercapacitor, which can greatly boost the energy density of the assembled device and expand the voltage window.

9.
Small ; 20(30): e2311013, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38372007

RESUMEN

The ability to design halide perovskite nanocrystals (PNCs) with circularly polarized luminescence (CPL) offers exceptional potential in photonic technologies. Despite recent inspiring advances, the creation of PNCs with full-color tailorablity, outstanding CPL, and long-term stability remains a substantial challenge. Herein, a robust strategy to craft CPL-active PNCs is reported, exhibiting appealing full-color tunable wavelengths, enhanced CPL, and prolonged stability. In contrast to conventional methodologies, this strategy utilizes chiral nematic mesoporous silica (CNMS) as host to render in situ confined growth of diverse achiral PNCs. By strategically engineering photonic bandgap, adjusting loading amount of PNCs, and manipulating cations/anion compositions of PNCs, robust CPL responses with tunable wavelength and intensity are successfully obtained. The resulting PNCs-CNMS achieves stable CPL emissions with full-color tunability and impressive luminescent dissymmetric factors up to -0.17. Remarkably, silica-based hosts as a protective barrier confer exceptional resistance to humidity, photodegradation, and thermal stability, even up to 95 °C. Furthermore, the ability to achieve reversible CPL switching within PNCs-CNMS is attainable by leveraging the responsiveness of CNMS matrix or dynamic behavior of impregnated PNCs. Additionally, circularly polarized light-emitting diode devices based on PNCs-CNMS can be conveniently fabricated. This research affords a powerful platform for designing functional chiroptical materials.

10.
Small ; 20(31): e2311750, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38459645

RESUMEN

The commercialization of lithium-sulfur (Li-S) battery is seriously hindered by the shuttle behavior of lithium (Li) polysulfide, slow conversion kinetics, and Li dendrite growth. Herein, a novel hierarchical p-type iron nitride and n-type vanadium nitride (p-Fe2N/n-VN) heterostructure with optimal electronic structure, confined in vesicle-like N-doped nanofibers (p-Fe2N/n-VN⊂PNCF), is meticulously constructed to work as "one stone two birds" dual-functional hosts for both the sulfur cathode and Li anode. As demonstrated, the d-band center of high-spin Fe atom captures more electrons from V atom to realize more π* and moderate σ* bond electron filling and orbital occupation; thus, allowing moderate adsorption intensity for polysulfides and more effective d-p orbital hybridization to improve reaction kinetics. Meanwhile, this unique structure can dynamically balance the deposition and transport of Li on the anode; thereby, more effectively inhibiting Li dendrite growth and promoting the formation of a uniform solid electrolyte interface. The as-assembled Li-S full batteries exhibit the conspicuous capacities and ultralong cycling lifespan over 2000 cycles at 5.0 C. Even at a higher S loading (20 mg cm-2) and lean electrolyte (2.5 µL mg-1), the full cells can still achieve an ultrahigh areal capacity of 16.1 mAh cm-2 after 500 cycles at 0.1 C.

11.
Small ; : e2404059, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39162125

RESUMEN

Sodium-ion batteries (SIBs) are a promising substitute for lithium batteries due to their abundant resources and low cost. Metal sulfides are regarded as highly attractive anode materials due to their superior mechanical stability and high theoretical specific capacity. Guided by the density functional theory (DFT) calculations, 3D porous network shaped Sb2S3/FeS2 composite materials with reduced graphene oxide (rGO) through a simple solvothermal and calcination method, which is predicted to facilitate favorable Na+ ion diffusion, is synthesized. Benefiting from the well-designed structure, the resulting Sb2S3/FeS2 exhibit a remarkable reversible capacity of 536 mAh g-1 after 2000 cycles at a current density of 5 A g-1 and long high-rate cycle life of 3000 cycles at a current density of 30 A g-1 as SIBs anode. In situ and ex situ analyses are carried out to gain further insights into the storage mechanisms and processes of sodium ions in Sb2S3/FeS2@rGO composites. The significantly enhanced sodium storage capacity is attributed to the unique structure and the heterogeneous interface between Sb2S3 and FeS2. This study illustrates that combining rGO with heterogeneous engineering can provide an ideal strategy for the synthesis of new hetero-structured anode materials with outstanding battery performance for SIBs.

12.
Small ; 20(6): e2304124, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37749960

RESUMEN

Sodium-ion batteries are a promising substitute for lithium batteries due to the abundant resources and low cost of sodium. Herein, honeycomb-shaped MoSe2 /reduced graphene oxide (rGO) composite materials are synthesized from graphene oxide (GO) and MoSe2 through a one-step solvothermal process. Experiments show that the 3D honeycomb structure provides excellent electrolyte penetration while alleviating the volume change during electrochemical cycling. An anode prepared with MoSe2 /rGO composites exhibits significantly improved sodium-ion storage properties, where a large reversible capacity of 215 mAh g-1 is obtained after 2700 cycles at the current density of 30.0 A g-1 or after 5900 cycles at 8.0 A g-1 . When such an anode is paired with Na3 V2 (PO4 )3 to form a full cell, a reversible specific capacity of 107.5 mAh g-1 can be retained after 1000 cycles at the current of 1.0 A g-1 . Transmission electron microscopy, X-ray photoelectron spectroscopy and in situ X-ray diffraction (XRD) characterization reveal the reversible storage reaction of Na ions in the MoSe2 /rGO composites. The significantly enhanced sodium storage capacity is attributed to the unique honeycomb microstructure and the use of ether-based electrolytes. This study illustrates that combining rGO with ether-based electrolytes has tremendous potential in constructing high-performance sodium-ion batteries.

13.
J Transl Med ; 22(1): 852, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39304928

RESUMEN

BACKGROUND: The syncytiotrophoblast (SCT) layer in the placenta serves as a crucial physical barrier separating maternal-fetal circulation, facilitating essential signal and substance exchange between the mother and fetus. Any abnormalities in its formation or function can result in various maternal syndromes, such as preeclampsia. The transition of proliferative villous cytotrophoblasts (VCT) from the mitotic cell cycle to the G0 phase is a prerequisite for VCT differentiation and their fusion into SCT. The imprinting gene P57Kip2, specifically expressed in intermediate VCT capable of fusion, plays a pivotal role in driving this key event. Moreover, aberrant expression of P57Kip2 has been linked to pathological placental conditions and adverse fetal outcomes. METHODS: Validation of STK40 interaction with P57Kip2 using rigid molecular simulation docking and co-immunoprecipitation. STK40 expression was modulated by lentivirus in BeWo cells, and the effect of STK40 on trophoblast fusion was assessed by real-time quantitative PCR, western blot, immunofluorescence, and cell viability and proliferation assays. Co-immunoprecipitation, transcriptome sequencing, and western blot were used to determine the potential mechanisms by which STK40 regulates P57Kip2. RESULTS: In this study, STK40 has been identified as a novel interacting protein with P57Kip2, and its expression is down-regulated during the fusion process of trophoblast cells. Overexpressing STK40 inhibited cell fusion in BeWo cells while stimulating mitotic cell cycle activity. Further experiments indicated that this effect is attributed to its specific binding to the CDK-binding and the Cyclin-binding domains of P57Kip2, mediating the E3 ubiquitin ligase COP1-mediated ubiquitination and degradation of P57Kip2. Moreover, abnormally high expression of STK40 might significantly contribute to the occurrence of preeclampsia. CONCLUSIONS: This study offers new insights into the role of STK40 in regulating the protein-level homeostasis of P57Kip2 during placental development.


Asunto(s)
Fusión Celular , Inhibidor p57 de las Quinasas Dependientes de la Ciclina , Proteínas Serina-Treonina Quinasas , Trofoblastos , Ubiquitina-Proteína Ligasas , Ubiquitinación , Femenino , Humanos , Embarazo , Proliferación Celular , Inhibidor p57 de las Quinasas Dependientes de la Ciclina/metabolismo , Inhibidor p57 de las Quinasas Dependientes de la Ciclina/genética , Unión Proteica , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteolisis , Trofoblastos/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética
14.
Rev Cardiovasc Med ; 25(4): 111, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-39076545

RESUMEN

Background: The C-reactive protein-albumin-lymphocyte (CALLY) index is a novel inflammatory biomarker, and its association with the prognosis of coronary artery disease (CAD) after percutaneous coronary intervention (PCI) has not previously been studied. Therefore, this study aimed to investigate the effect of using the CALLY index on adverse outcomes in CAD patients undergoing PCI. Methods: From December 2016 to October 2021, we consecutively enrolled 15,250 CAD patients and performed follow-ups for primary endpoints consisting of all-cause mortality (ACM) and cardiac mortality (CM). The CALLY index was computed using the following formula: (albumin × lymphocyte)/(C-reactive protein (CRP) × 10 4 ). The average duration of the follow-up was 24 months. Results: A total of 3799 CAD patients who had undergone PCI were ultimately enrolled in the present study. The patients were divided into four groups according to the CALLY index quartiles: Q1 ( ≤ 0.69, n = 950), Q2 (0.69-2.44, n = 950), Q3 (2.44-9.52, n = 950), and Q4 ( > 9.52, n = 949). The low-Q1 group had a significantly higher prevalence of ACM (p < 0.001), CM (p < 0.001), major adverse cardiac events (MACEs) (p = 0.002), and major adverse cardiac and cerebrovascular events (MACCEs) (p = 0.002). Kaplan-Meier analysis revealed that a low CALLY index was significantly linked with adverse outcomes. After univariate and multivariate Cox regression analysis, the risk of ACM, CM, MACEs, and MACCEs decreased by 73.7% (adjust hazard risk [HR] = 0.263, 95% CI: 0.147-0.468, p < 0.001), 70.6% (adjust HR = 0.294, 95% CI: 0.150-0.579, p < 0. 001), 37.4% (adjust HR = 0.626, 95% CI: 0.422-0.929, p = 0.010), and 41.5% (adjust HR = 0.585, 95% CI: 0.401-0.856, p = 0.006), respectively, in the Q4 quartiles compared with the Q1 quartiles. Conclusions: This study revealed that a decreased CALLY index was associated with worse prognoses for CAD patients after PCI. The categorization of patients with a decreased CALLY index could provide valuable evidence for the risk stratification of adverse outcomes in CAD patients after PCI. Clinical Trial Registration: The details are available at http://www.chictr.org.cn (Identifier: NCT05174143).

15.
Cancer Cell Int ; 24(1): 200, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38840243

RESUMEN

Ferroptosis, an iron-dependent regulated cell death mechanism, holds significant promise as a therapeutic strategy in oncology. In the current study, we explored the regulatory effects of epigallocatechin gallate (EGCG), a prominent polyphenol in green tea, on ferroptosis and its potential therapeutic implications for non-small cell lung cancer (NSCLC). Treatment of NSCLC cell lines with varying concentrations of EGCG resulted in a notable suppression of cell proliferation, as evidenced by a reduction in Ki67 immunofluorescence staining. Western blot analyses demonstrated that EGCG treatment led to a decrease in the expression of glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11) while increasing the levels of acyl-CoA synthetase long-chain family member 4 (ACSL4). These molecular changes were accompanied by an increase in intracellular iron, malondialdehyde (MDA), and reactive oxygen species (ROS), alongside ultrastructural alterations characteristic of ferroptosis. Through small RNA sequencing and RT-qPCR, transfer RNA-derived small RNA 13502 (tsRNA-13502) was identified as a significant target of EGCG action, with its expression being upregulated in NSCLC tissues compared to adjacent non-tumorous tissues. EGCG was found to modulate the ferroptosis pathway by downregulating tsRNA-13502 and altering the expression of key ferroptosis regulators (GPX4/SLC7A11 and ACSL4), thereby promoting the accumulation of iron, MDA, and ROS, and ultimately inducing ferroptosis in NSCLC cells. This study elucidates EGCG's multifaceted mechanisms of action, underscoring the modulation of ferroptosis as a viable therapeutic approach for enhancing NSCLC treatment outcomes.

16.
Eur Radiol ; 34(10): 6831-6842, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38514481

RESUMEN

OBJECTIVES: This study aimed to construct a radiomics-based model for prognosis and benefit prediction of concurrent chemoradiotherapy (CCRT) versus intensity-modulated radiotherapy (IMRT) in locoregionally advanced nasopharyngeal carcinoma (LANPC) following induction chemotherapy (IC). MATERIALS AND METHODS: A cohort of 718 LANPC patients treated with IC + IMRT or IC + CCRT were retrospectively enrolled and assigned to a training set (n = 503) and a validation set (n = 215). Radiomic features were extracted from pre-IC and post-IC MRI. After feature selection, a delta-radiomics signature was built with LASSO-Cox regression. A nomogram incorporating independent clinical indicators and the delta-radiomics signature was then developed and evaluated for calibration and discrimination. Risk stratification by the nomogram was evaluated with Kaplan-Meier methods. RESULTS: The delta-radiomics signature, which comprised 19 selected features, was independently associated with prognosis. The nomogram, composed of the delta-radiomics signature, age, T category, N category, treatment, and pre-treatment EBV DNA, showed great calibration and discrimination with an area under the receiver operator characteristic curve of 0.80 (95% CI 0.75-0.85) and 0.75 (95% CI 0.64-0.85) in the training and validation sets. Risk stratification by the nomogram, excluding the treatment factor, resulted in two groups with distinct overall survival. Significantly better outcomes were observed in the high-risk patients with IC + CCRT compared to those with IC + IMRT, while comparable outcomes between IC + IMRT and IC + CCRT were shown for low-risk patients. CONCLUSION: The radiomics-based nomogram can predict prognosis and survival benefits from concurrent chemotherapy for LANPC following IC. Low-risk patients determined by the nomogram may be potential candidates for omitting concurrent chemotherapy during IMRT. CLINICAL RELEVANCE STATEMENT: The radiomics-based nomogram was constructed for risk stratification and patient selection. It can help guide clinical decision-making for patients with locoregionally advanced nasopharyngeal carcinoma following induction chemotherapy, and avoid unnecessary toxicity caused by overtreatment. KEY POINTS: • The benefits from concurrent chemotherapy remained controversial for locoregionally advanced nasopharyngeal carcinoma following induction chemotherapy. • Radiomics-based nomogram achieved prognosis and benefits prediction of concurrent chemotherapy. • Low-risk patients defined by the nomogram were candidates for de-intensification.


Asunto(s)
Quimioradioterapia , Quimioterapia de Inducción , Imagen por Resonancia Magnética , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Nomogramas , Radioterapia de Intensidad Modulada , Humanos , Masculino , Carcinoma Nasofaríngeo/diagnóstico por imagen , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/tratamiento farmacológico , Femenino , Persona de Mediana Edad , Neoplasias Nasofaríngeas/diagnóstico por imagen , Neoplasias Nasofaríngeas/terapia , Neoplasias Nasofaríngeas/tratamiento farmacológico , Estudios Retrospectivos , Quimioradioterapia/métodos , Imagen por Resonancia Magnética/métodos , Pronóstico , Adulto , Anciano , Radiómica
17.
J Org Chem ; 89(1): 474-483, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38096480

RESUMEN

A radical 1,2,4-trifunctional reaction of thiosulfonate to unactivated olefin is achieved by a migration strategy under mild conditions. In this reaction, the more unstable primary free radicals are in situ generated after the migration of heteroaryl groups in the presence of DABCO. This trifunctionalization of unactivated olefins involves two C-S bond formations and one C-C bond formation.

18.
J Org Chem ; 89(1): 363-372, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38085815

RESUMEN

Herein, we have developed a new method for the synthesis of ((methyl-d3)sulfonyl)ethyne, which is cost-effective and environmentally friendly and can be synthesized at the gram level. As an ideal thiol-yne reagent, it can be reacted with various types of thiols to afford (Z)- and (E)-type vinyl sulfides under different conditions with high selectivity. In addition, it can complete the conformational transition from Z- to E-type products under suitable conditions, and can also carry out further derivatization smoothly. The deuterium content of all products was greater than 99%. The preliminary mechanistic studies support the visible light-mediated radical course, and herein provide a novel and efficient synthetic strategy for the direct introduction of deuterated methyl groups, enriching the methods for the construction of C-S bond-containing compounds.

19.
J Org Chem ; 89(18): 13386-13400, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39258469

RESUMEN

A tandem cyclization reaction of enynones with tetrasulfides has been developed under manganese-promoted conditions, leading to the high-yield formation of various furanmethyl disulfides. This reaction is characterized by readily available starting materials, mild reaction conditions, and a broad substrate scope, making it attractive and practical. It provides a new strategy for the synthesis of disulfide-containing functionalized furans.

20.
J Org Chem ; 89(12): 8804-8814, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38860924

RESUMEN

1,4-/1,3-Regioselective bifunctionalization of 1,3-enynes with selenosulfonates in water under catalyst-free conditions for the construction of sulfonyl allene and 1,3-disulfonyl-conjugated dienes respectively have been developed. The reactions feature mild reaction conditions in aqueous solution and remarkable regioselectivity controlled by substrates.

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