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1.
IEEE Trans Biomed Eng ; PP2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39172621

RESUMO

OBJECTIVE: To achieve a contactless and damage-less extraction of a single (or a few) human retinal pigment epithelial (RPE) cell(s) from a cell monolayer with acoustic droplet ejection. METHODS: An acoustic droplet ejector based on a self-focusing acoustic transducer (SFAT) is designed, microfabricated, and placed on a precision movable stage that aligns it to the targeted cell(s) in a Petri dish. The device delivers 20.1 MHz focused ultrasound (FUS) with a focal diameter of 100 µm, which ejects droplets capable of extracting and transferring only the targeted cell(s) from a monolayer. RESULTS: The extraction and collection of 1-10 cells are successfully demonstrated. The number of ejected cells can be controlled by the FUS pulse width. As confirmed by fluorescence-based cell viability assays and re-culture experiments, the ejected cell(s) and remaining monolayer cells are intact without damage after cell ejection. Furthermore, real-time reverse transcription polymerase chain reaction (RT-PCR) tests for both housekeeping genes (GAPDH and ß -actin) and RPE-specific genes (MITF, PEDF, and PMEL17) show no significant difference between the acoustically ejected cells and those collected manually with a micropipette. CONCLUSION: The proposed technology realizes a contactless, damage-free extraction of cells with high spatial resolution and precise control of the number of cells ejected, with a simple setup. SIGNIFICANCE: This powerful technology not only enables efficient, high-precision cell extraction for quality check applications but also opens new avenues for other advanced biotechnologies such as bioprinting.

2.
J Chem Phys ; 161(8)2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39171714

RESUMO

Low-dimensional nanostructures, especially one-dimensional materials, exhibit remarkable anisotropic characteristics due to their low symmetry, making them promising candidates for polarization-sensitive photodetection. Here, we present a chemical vapor deposition synthesis method for tellurium suboxide (TeOx), confirming the practicality of photodetectors constructed from TeOx nanowires (NWs) in high-responsivity, broadband, and polarization-sensitive detection. By precisely controlling the thermodynamics and kinetics of TeOx NWs growth, we achieve large-scale growth of TeOx NWs with highly controllable dimensions and propose a method to induce intrinsic built-in strain in TeOx NWs. Photodetectors based on quasi-one-dimensional TeOx NWs with ohmic contact demonstrate broadband spectral response (638-1550 nm), high responsivity (13 700 mA·W-1), and superior air stability. Particularly, owing to the inherent structural anisotropy of the photodetectors, they exhibit polarization-sensitive photodetection, with anisotropy ratios of 1.70 and 1.71 at 638 and 808 nm, respectively.

3.
Proc Natl Acad Sci U S A ; 121(31): e2319193121, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39052833

RESUMO

Iron-based hexacyanoferrate (Fe-HCF) are promising cathode materials for sodium-ion batteries (SIBs) due to their unique open-channel structure that facilitates fast ion transport and framework stability. However, practical implementation of SIBs has been hindered by low initial Coulombic efficiency (ICE), poor rate performance, and short lifespan. Herein, we report a coordination engineering to synthesize sodium-rich Fe-HCF as cathodes for SIBs through a uniquely designed 10-kg-scale chemical reactor. Our study systematically investigated the relationship between coordination surroundings and the electrochemical behavior. Building on this understanding, the cathode delivered a reversible capacity of 99.3 mAh g-1 at 5 C (1 C = 100 mA g-1), exceptional rate capability (51 mAh g-1 even at 100 C), long lifespan (over 15,000 times at 50 C), and a high ICE of 92.7%. A full cell comprising the Fe-HCF cathode and hard carbon (HC) anode exhibited an impressive cyclic stability with a high-capacity retention rate of 98.3% over 1,000 cycles. Meanwhile, this material can be readily scaled to the practical levels of yield. The findings underscore the potential of Fe-HCF as cathodes for SIBs and highlight the significance of controlling nucleation and morphology through coordination engineering for a sustainable energy storage system.

4.
Nano Lett ; 24(25): 7716-7723, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38848111

RESUMO

Mixed-dimensional heterostructures integrate materials of diverse dimensions with unique electronic functionalities, providing a new platform for research in electron transport and optoelectronic detection. Here, we report a novel covalently bonded one-dimensional/two-dimensional (1D/2D) homojunction structure with robust junction contacts, which exhibits wide-spectrum (from the visible to near-infrared regions), self-driven photodetection, and polarization-sensitive photodetection capabilities. Benefiting from the ultralow dark current at zero bias voltage, the on/off ratio and detectivity of the device reach 1.5 × 103 and 3.24 × 109 Jones, respectively. Furthermore, the pronounced anisotropy of the WSe2 1D/2D homojunction is attributed to its low symmetry, enabling polarization-sensitive detection. In the absence of any external bias voltage, the device exhibits strong linear dichroism for wavelengths of 638 and 808 nm, with anisotropy ratios of 2.06 and 1.96, respectively. These results indicate that such mixed-dimensional structures can serve as attractive building blocks for novel optoelectronic detectors.

5.
Nano Lett ; 24(25): 7724-7731, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38864413

RESUMO

Perovskite monocrystalline films are regarded as desirable candidates for the integration of high-performance optoelectronics due to their unique photophysical properties. However, the heterogeneous integration of a perovskite monocrystalline film with other semiconductors is fundamentally limited by the lattice mismatch, which hinders direct epitaxy. Herein, the van der Waals (vdW) integration strategy for 3D perovskites is developed, where perovskite monocrystalline films are epitaxially grown on the mother substrate, followed by its peeling off and transferring to arbitrary semiconductors, forming monocrystalline heterojunctions. The as-achieved CsPbBr3-Nb-doped SrTiO3 (Nb:STO) vdW p-n heterojunction exhibited comparable performance to their directly epitaxial counterpart, demonstrating the feasibility of vdW integration for 3D perovskites. Furthermore, the vdW integration could be extended to silicon substrates, rendering the CsPbBr3-n-Si and CsPbCl3-p-Si p-n heterojunction with apparent rectification behaviors and photoresponse. The vdW integration significantly enriches the selections of semiconductors hybridizing with perovskites and provides opportunities for monocrystalline perovskite optoelectronics with complex configurations and multiple functionalities.

6.
Adv Mater ; 36(32): e2405170, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38838950

RESUMO

High-entropy strategies are regarded as a powerful means to enhance performance in energy storage fields. The improved properties are invariably ascribed to entropy stabilization or synergistic cocktail effect. Therefore, the manifested properties in such multicomponent materials are usually unpredictable. Elucidating the precise correlations between atomic structures and properties remains a challenge in high-entropy materials (HEMs). Herein, atomic-resolution scanning transmission electron microscopy annular dark field (STEM-ADF) imaging and four dimensions (4D)-STEM are combined to directly visualize atomic-scale structural and electric information in high-entropy FeMnNiVZnPS3. Aperiodic stacking is found in FeMnNiVZnPS3 accompanied by high-density strain soliton boundaries (SSBs). Theoretical calculation suggests that the formation of such structures is attributed to the imbalanced stress of distinct metal-sulfur bonds in FeMnNiVZnPS3. Interestingly, the electric field concentrates along the two sides of SSBs and gradually diminishes toward the two-dimensional (2D) plane to generate a unique electric field gradient, strongly promoting the ion-diffusion rate. Accordingly, high-entropy FeMnNiVZnPS3 demonstrates superior ion-diffusion coefficients of 10-9.7-10-8.3 cm2 s-1 and high-rate performance (311.5 mAh g-1 at 30 A g-1). This work provides an alternative way for the atomic-scale understanding and design of sophisticated HEMs, paving the way for property engineering in multi-component materials.

7.
Curr Atheroscler Rep ; 26(8): 383-394, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38878139

RESUMO

PURPOSE OF REVIEW: The primary objective of this review is to explore the pathophysiological roles and clinical implications of lipoprotein(a) [Lp(a)] in the context of atherosclerotic cardiovascular disease (ASCVD). We seek to understand how Lp(a) contributes to inflammation and arteriosclerosis, aiming to provide new insights into the mechanisms of ASCVD progression. RECENT FINDINGS: Recent research highlights Lp(a) as an independent risk factor for ASCVD. Studies show that Lp(a) not only promotes the inflammatory processes but also interacts with various cellular components, leading to endothelial dysfunction and smooth muscle cell proliferation. The dual role of Lp(a) in both instigating and, under certain conditions, mitigating inflammation is particularly noteworthy. This review finds that Lp(a) plays a complex role in the development of ASCVD through its involvement in inflammatory pathways. The interplay between Lp(a) levels and inflammatory responses highlights its potential as a target for therapeutic intervention. These insights could pave the way for novel approaches in managing and preventing ASCVD, urging further investigation into Lp(a) as a therapeutic target.


Assuntos
Aterosclerose , Inflamação , Lipoproteína(a) , Humanos , Lipoproteína(a)/metabolismo , Lipoproteína(a)/sangue , Aterosclerose/metabolismo , Aterosclerose/imunologia , Inflamação/metabolismo , Animais , Fatores de Risco
8.
Cancer Control ; 31: 10732748241251571, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38869038

RESUMO

OBJECTIVES: To determine the dysregulated signaling pathways of head and neck squamous cell carcinoma associated with circulating tumor cells (CTCs) via single-cell molecular characterization. INTRODUCTION: Head and neck squamous cell carcinoma (HNSCC) has a significant global burden and is a disease with poor survival. Despite trials exploring new treatment modalities to improve disease control rates, the 5 year survival rate remains low at only 60%. Most cancer malignancies are reported to progress to a fatal phase due to the metastatic activity derived from treatment-resistant cancer cells, regarded as one of the most significant obstacles to develope effective cancer treatment options. However, the molecular profiles of cancer cells have not been thoroughly studied. METHODS: Here, we examined in-situ HNSCC tumors and pairwisely followed up with the downstream circulating tumor cells (CTCs)-based on the surrogate biomarkers to detect metastasis that is established in other cancers - not yet being fully adopted in HNSCC treatment algorithms. RESULTS: Specifically, we revealed metastatic HNSCC patients have complex CTCs that could be defined through gene expression and mutational gene profiling derived from completed single-cell RNASeq (scRNASeq) that served to confirm molecular pathways inherent in these CTCs. To enhance the reliability of our findings, we cross-validated those molecular profiles with results from previously published studies. CONCLUSION: Thus, we identified 5 dysregulated signaling pathways in CTCs to derive HNSCC biomarker panels for screening HNSCC in situ tumors.


ObjectivesInvestigating the dysregulated signaling pathways of head and neck squamous cell carcinoma (HNSCC) linked with circulating tumor cells (CTCs) using single-cell molecular characterization.IntroductionHNSCC poses a significant global health burden with poor survival rates despite advancements in treatment. Metastatic activity from treatment-resistant cancer cells remains a major challenge in developing effective treatments. However, the molecular profiles of cancer cells, particularly CTCs, are not well-understood.MethodsWe analyzed in-situ HNSCC tumors and corresponding CTCs using surrogate biomarkers to detect metastasis, a technique not widely used in HNSCC treatment protocols.ResultsOur study revealed complex CTCs in metastatic HNSCC patients characterized by gene expression and mutational gene profiling via single-cell RNASeq (scRNASeq). These profiles confirmed molecular pathways inherent in CTCs, further validated by previous research.ConclusionThrough our research, we identified five dysregulated signaling pathways in CTCs, suggesting potential biomarker panels for HNSCC screening in situ tumors.


Assuntos
Neoplasias de Cabeça e Pescoço , Células Neoplásicas Circulantes , Transdução de Sinais , Análise de Célula Única , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/sangue , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/sangue , Neoplasias de Cabeça e Pescoço/metabolismo , Análise de Célula Única/métodos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/sangue , Masculino , Feminino , Perfilação da Expressão Gênica/métodos , Pessoa de Meia-Idade , Regulação Neoplásica da Expressão Gênica
9.
Patterns (N Y) ; 5(5): 100969, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38800361

RESUMO

Understanding the cellular composition of a disease-related tissue is important in disease diagnosis, prognosis, and downstream treatment. Recent advances in single-cell RNA-sequencing (scRNA-seq) technique have allowed the measurement of gene expression profiles for individual cells. However, scRNA-seq is still too expensive to be used for large-scale population studies, and bulk RNA-seq is still widely used in such situations. An essential challenge is to deconvolve cellular composition for bulk RNA-seq data based on scRNA-seq data. Here, we present DeepDecon, a deep neural network model that leverages single-cell gene expression information to accurately predict the fraction of cancer cells in bulk tissues. It provides a refining strategy in which the cancer cell fraction is iteratively estimated by a set of trained models. When applied to simulated and real cancer data, DeepDecon exhibits superior performance compared to existing decomposition methods in terms of accuracy.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38648125

RESUMO

As a building block of knowledge acquisition, knowledge graph completion (KGC) aims at inferring missing facts in knowledge graphs (KGs) automatically. Previous studies mainly focus on graph convolutional network (GCN)-based KG embedding (KGE) to determine the representations of entities and relations, accordingly predicting missing triplets. However, most existing KGE methods suffer from limitations in predicting tail entities that are far away or even unreachable in KGs. This limitation can be attributed to the related high-order information being largely ignored. In this work, we focus on learning the information from the related high-order neighbors in KGs to improve the performance of prediction. Specifically, we first introduce a set of new nodes called pedal nodes to augment the KGs for facilitating message passing between related high-order entities, effectively injecting the information of high-order neighbors into entity representation. Additionally, we propose strength-guided graph neural networks to aggregate neighboring entity representations. To address the issue of transmitting irrelevant higher order information to entities through pedal nodes, which can potentially hurt entity representation, we further propose to dynamically integrate the aggregated representation of each node with its corresponding self-representation. Extensive experiments have been conducted on three benchmark datasets and the results demonstrate the superiority of our method compared to strong baseline models.

11.
Soft Matter ; 20(17): 3612-3619, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38619442

RESUMO

Herein, a self-healing polyacrylate system was successfully prepared by introducing crosslinking agents containing disulfide bonds and monomers capable of forming quadruple hydrogen bonds through free radical copolymerization. This polymer material exhibited good toughness and self-healing properties through chemical and physical dual dynamic networks while maintaining excellent mechanical properties, which expanded the development path of self-healing acrylate materials. Compared to uncrosslinked and single dynamically crosslinked polymers, its elongation at break was as high as 437%, and its tensile strength was 5.48 MPa. Due to the presence of dual reversible dynamic bonds in the copolymer system, good self-healing was also achieved at 60 °C. In addition, differential scanning calorimetry and thermogravimetric analysis measurements confirmed that the thermal stability and glass transition temperature of the material were improved owing to the presence of physical and chemical cross-linking networks.

12.
J Colloid Interface Sci ; 668: 77-87, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38669998

RESUMO

Transition-metal-atom anchored graphdiynes (TM@GDY, TM = Mn, Fe, Co, Ni and Cu) have already been synthesized and found applications in hydrogen evolution, nitrogen fixation and etc. By means of first-principle predictions and test experiments, we propose here that Fe@GDY and Co@GDY are efficient catalysts for the sustainable conversion of O3 to O2. These two catalysts can spontaneously chemisorb O3 with zero reaction barrier and have low O3 conversion barriers (0.31 eV and 0.19 eV, respectively). The O3 decomposition experiment in a continuous flow membrane reactor and electron paramagnetic resonance results verify that Fe@GDY and Co@GDY are efficient catalysts under humid conditions. Raman spectra prove the formation of the key Fe-O/Co-O and FeOO and CoOO intermediates. The hydrophobic nature of graphdiyne and the strongest chemisorption of O3 among tested ambient gases, make Fe@GDY and Co@GDY ideal catalysts under both dry and humid conditions. These findings would stimulate future explorations on metal anchored GDY-based catalysts for applications of toxic gas decomposition or fixation.

13.
Small ; 20(32): e2400315, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38488741

RESUMO

Currently, a major target in the development of Na-ion batteries is the concurrent attainment of high-rate capacity and long cycling stability. Herein, an advanced Na-ion battery with high-rate capability and long cycle stability based on Li/Ti co-doped P2-type Na0.67Mn0.67Ni0.33O2, a host material with high-voltage zero-phase transition behavior and fast Na+ migration/conductivity during dynamic de-embedding process, is constructed. Experimental results and theoretical calculations reveal that the two-element doping strategy promotes a mutually reinforcing effect, which greatly facilitates the transfer capability of Na+. The cation Ti4+ doping is a dominant high voltage, significantly elevating the operation voltage to 4.4 V. Meanwhile, doping Li+ shows the function in charge transfer, improving the rate performance and prolonging cycling lifespan. Consequently, the designed P2-Na0.75Mn0.54Ni0.27Li0.14Ti0.05O2 cathode material exhibits discharge capacities of 129, 104, and 85 mAh g- 1 under high voltage of 4.4 V at 1, 10, and 20 C, respectively. More importantly, the full-cell delivers a high initial capacity of 198 mAh g-1 at 0.1 C (17.3 mA g-1) and a capacity retention of 73% at 5 C (865 mA g-1) after 1000 cycles, which is seldom witnessed in previous reports, emphasizing their potential applications in advanced energy storage.

14.
Int Wound J ; 21(2): e14762, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38356162

RESUMO

Ischemic ulcers pose a multifaceted clinical dilemma for patients with atherosclerosis, frequently compounded by suboptimal wound healing mechanisms. The dual function of Transforming Growth Factor Beta 3 (TGF-ß3) in ischemic ulcer healing is not fully comprehended, despite its involvement in modulating inflammatory responses and tissue regeneration. The main aim of this investigation was to clarify the functions and mechanisms by which TGF-ß3 regulates inflammatory responses and promotes wound healing in patients with ischemic ulcers who have atherosclerosis. Between August 2022 and November 2023, this cross-sectional investigation was conducted on 428 patients diagnosed with atherosclerotic ischemic ulcers in Haikou, China. The expression and function of TGF-ß3 were examined throughout the different stages of wound healing, including inflammation, proliferation and remodelling. In addition to documenting patient demographics and ulcer characteristics, an analysis was conducted on biopsy samples to determine the expression of TGF-ß3, pro-inflammatory and anti-inflammatory markers. A subset of patients were administered topical TGF-ß3 in order to evaluate its therapeutic effects. The expression pattern of TGF-ß3 was found to be stage-dependent and significant, exhibiting increased levels during the phase of inflammation and reduced activity in subsequent phases. TGF-ß3 levels were found to be greater in ulcers that were larger and deeper, especially in inflammatory phase. TGF-ß3 applied topically induced discernible enhancement in ulcer healing parameters, such as reduction in ulcer depth and size. The therapeutic significance of TGF-ß3 was emphasised due to its twofold function of regulating the inflammatory environment and facilitating the regeneration of damaged tissues. Ischemic ulcer lesion healing is significantly influenced by TGF-ß3, which functions as an anti-inflammatory and pro-inflammatory mediator. Its correlation with ulcer characteristics and stages of healing suggests that it may have utility as a targeted therapeutic agent.


Assuntos
Aterosclerose , Fator de Crescimento Transformador beta3 , Humanos , Anti-Inflamatórios , Estudos Transversais , Inflamação , Fator de Crescimento Transformador beta/análise , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta3/uso terapêutico , Fator de Crescimento Transformador beta3/farmacologia , Úlcera , Cicatrização
15.
Neural Netw ; 169: 134-142, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37890363

RESUMO

Relation extraction is one of the most essential tasks of knowledge construction, but it depends on a large amount of annotated data corpus. Few-shot relation extraction is proposed as a new paradigm, which is designed to learn new relationships between entities with merely a small number of annotated instances, effectively mitigating the cost of large-scale annotation and long-tail problems. To generalize to novel classes not included in the training set, existing approaches mainly focus on tuning pre-trained language models with relation instructions and developing class prototypes based on metric learning to extract relations. However, the learned representations are extremely sensitive to discrepancies in intra-class and inter-class relationships and hard to adaptively classify the relations due to biased class features and spurious correlations, such as similar relation classes having closer inter-class prototype representation. In this paper, we introduce an adaptive class augmented prototype network with instance-level and representation-level augmented mechanisms to strengthen the representation space. Specifically, we design the adaptive class augmentation mechanism to expand the representation of classes in instance-level augmentation, and class augmented representation learning with Bernoulli perturbation context attention to enhance the representation of class features in representation-level augmentation and explore adaptive debiased contrastive learning to train the model. Experimental results have been demonstrated on FewRel and NYT-25 under various few-shot settings, and the proposed model has improved accuracy and generalization, especially for cross-domain and different hard tasks.


Assuntos
Generalização Psicológica , Aprendizagem , Conhecimento , Idioma
16.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1039048

RESUMO

Glioblastoma (GBM), one of the most common malignant tumors in the central nervous system (CNS), is characterized by diffuse and invasive growth as well as resistance to various combination therapies. GBM is the most prevalent type with the highest degree of malignancy and the worst prognosis. While current clinical treatments include surgical resection, radiotherapy, temozolomide chemotherapy, novel molecular targeted therapy, and immunotherapy, the median survival time of GBM patients is only about one year. Radiotherapy is one of the important treatment modalities for GBM, which relies on ionizing radiation to eradicate tumor cells. Approximately 60% to 70% of patients need to receive radiotherapy as postoperative radiotherapy or neoadjuvant radiotherapy during the treatment process. However, during radiotherapy, the radioresistant effect caused by DNA repair activation and cell apoptosis inhibition impedes the therapeutic effect of malignant glioblastoma.Ferroptosis was first proposed by Dr. Brent R. Stockwell in 2012. It is an iron-dependent mode of cell death induced by excessive lipid peroxidation. Although the application of ferroptosis in tumor therapy is still in the exploratory stage, it provides a completely new idea for tumor therapy as a novel form of cell death. Ferroptosis has played a significant role in the treatment of GBM. Specifically, research has revealed the key processes of ferroptosis occurrence, including intracellular iron accumulation, reactive oxygen species (ROS) generation, lipid peroxidation, and a decrease in the activity of the antioxidant system. Among them, glutathione peroxidase 4(GPX4) in the cytoplasm and mitochondria, ferroptosis suppressor protein 1 (FSP1) on the plasma membrane, and dihydroorotate dehydrogenase (DHODH) in the mitochondria constitute an antioxidant protection system against ferroptosis. In iron metabolism, nuclear receptor coactivator 4 (NCOA4) can mediate ferritin autophagy to regulate intracellular iron balance based on intracellular iron content. Heme oxygenase1 (HMOX1) catalyzes heme degradation to release iron and regulate ferroptosis. Radiation can trigger ferroptosis by generating ROS, inhibiting the signaling axis of the antioxidant system, depleting glutathione, upregulating acyl-CoA synthase long chain family member 4 (ACSL4), and inducing autophagy. Interestingly, some articles has documented that exposure to low doses of radiation (6 Gy for 24 h or 8 Gy for 4-12 h) can induce the expression of SLC7A11 and GPX4 in breast cancer and lung cancer cells, leading to radiation resistance, while radiation-induced ferroptosis occurs after 48 h. In contrast, high doses of ionizing radiation (20 Gy and 50 Gy) increase lipid peroxidation after 24 h. This suggests that radiation-induced oxidative stress is a double-edged sword that can regulate ferroptosis in both directions, and the ultimate fate of cells after radiation exposure——developing resistance and achieving homeostasis or undergoing ferroptosis——depends on the degree and duration of membrane lipid damage caused by the radiation dose. In addition, during the process of radiotherapy, methods such as inducing iron overload, damaging the antioxidant system, and disrupting mitochondrial function are used to target ferroptosis, thereby enhancing the radiosensitivity of glioblastoma. By promoting the occurrence of ferroptosis in tumor cells as a strategy to improve radiotherapy sensitivity, we can enhance the killing effect of ionizing radiation on tumor cells, thus providing more treatment options for patients with glioblastoma. In this paper, we reviewed ferroptosis and its mechanism, analyzed the molecular mechanism of radiation-induced ferroptosis, and discussed the effective strategies to regulate ferroptosis in enhancing the sensitivity of radiotherapy, with a view to providing an important reference value for improving the current status of glioblastoma treatment.

17.
JAMA Oncol ; 10(2): 220-226, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38153755

RESUMO

Importance: Chronic graft-vs-host disease (GVHD) limits the long-term benefit of haploidentical hematopoietic stem cell transplant (HSCT). This clinical trial evaluated repeated infusions of umbilical cord mesenchymal stem cells (MSCs) during the early stage (45 days and 100 days) after haplo-HSCT to prevent chronic GVHD. Objective: To determine whether repeated infusions of MSCs during the early stage after haplo-HSCT decreases the incidence of severe chronic GVHD. Design, Setting, and Participants: This open-label, multicenter, parallel randomized clinical trial was conducted from April 2016 to January 2022. Eligibility criteria included a diagnosis of acute leukemia and having a haploidentical, suitable related donor for HSCT. The median (range) follow-up time was 39.0 (1.5-67.0) months. Interventions: The enrolled patients with a haploidentical relative for HSCT received the modified busulfan/cyclophosphamide + antithymocyte globulin modified regimen and standard GVHD prophylaxis. Patients were randomly chosen to receive MSCs (the MSC group) (1 × 106 cells/kg, every 2 weeks, starting from 45 days after transplant, 4 times total) or regular prophylaxis (control group). Main Outcome and Measure: The cumulative incidence of severe chronic GVHD. Results: Of 158 patients, 58 (36.7%) were female individuals; the median (range) age for the MSC and control groups was 28 (18-60) years and 28 (18-56) years, respectively. A total of 158 patients were screened, and 148 patients were randomly assigned to the MSC group (n = 74) or control group (n = 74) 1 day before MSCs infusion. The estimated 2-year cumulative incidence of severe chronic GVHD was 5.4% (95% CI, 1.8%-14.0%) in the MSC group and 17.4% (95% CI, 10.1%-28.5%) in the control group (hazard ratio [HR], 0.29; 95% CI, 0.10-0.88; P = .03). There was no difference between the MSC and control groups in the cumulative incidence of leukemia relapse (HR, 1.17; 95% CI, 0.55-2.47; P = .68). The cumulative incidence of stage II to IV acute GVHD in the MSC group was significantly lower than that in the control group (HR, 0.25; 95% CI, 0.09-0.67; P = .01). The MSC group had better GVHD-free and relapse-free survival rates than the control group (HR, 0.62; 95% CI, 0.39-0.98; P = .04). Conclusions and Relevance: The results of this randomized clinical trial show that early repeated infusions of MSCs decreased the incidence and severity of chronic GVHD, and the incidence and severity of acute GVHD manifested as a better GVHD-free and relapse-free survival rate for patients after haplo-HSCT. Trial Registration: Chinese Clinical Trial Registry: ChiCTR-IIR-16007806.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Células-Tronco Mesenquimais , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Masculino , Transplante de Células-Tronco Hematopoéticas/métodos , Doença Enxerto-Hospedeiro/etiologia , Ciclofosfamida/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico
18.
Food Chem X ; 20: 101001, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38144726

RESUMO

Distiller grains are the main by-products of Baijiu production and are usually discarded, ignoring their abundant functional phytochemicals. The free and bound polyphenols from distiller grains were extracted and their potential effect on modulating fecal microbiota was investigated using in vitro fecal fermentation. The results showed that 34 polyphenols were quantified from distiller grains. The antioxidant activity was positively correlated with quercetin, myricetin, epicatechin, and naringenin. The abundance of Bifidobacterium, Ruminobacterium, Lactobacillus, Akkermansia, and butyrate-producing bacteria was enhanced by distiller's grain polyphenols by approximately 10.66-, 6.39-, 7.83-, 2.59-, and 7.74-fold, respectively. Moreover, the production of short-chain fatty acids (SCFAs), especially acetic, butyric, and propionic acid, was promoted (increased 1.99-, 1.71-, and 1.34-fold, respectively). Correlated analysis revealed quercetin, daidzein, and kaempferol as the key polyphenols by analyzing the effects on gut microbiota and SCFAs. This study could provide a reference for converting distiller grains into high-nutrient functional food ingredients and feeds.

19.
World J Clin Cases ; 11(30): 7463-7468, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37969459

RESUMO

BACKGROUND: There have been no reports of acute-on-chronic liver failure (ACLF) during treatment of chronic hepatitis C (CHC) with direct-acting antivirals (DAAs). CASE SUMMARY: We report a 50-year-old male patient with CHC. The patient sought medical attention from the Department of Infectious Diseases at our hospital due to severe yellowing of the skin and sclera, which developed 3 mo previously and attended two consecutive hospitals without finding the cause of liver damage. It was not until 1 mo ago that he was diagnosed with CHC at our hospital. After discharge, he was treated with DAAs. During treatment, ACLF occurred, and timely measures such as liver protection, enzyme lowering, anti-infective treatment, and suppression of inflammatory storms were implemented to control the condition. CONCLUSION: DAA drugs significantly improve the cure rate of CHC. However, when patients have factors such as autoimmune attack, coinfection, or unclear hepatitis C virus genotype, close monitoring is required during DAA treatment.

20.
Food Chem X ; 19: 100747, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37780293

RESUMO

Rosa roxburghii Tratt distiller's grains (R. roxburghii DGs), the main by-product of wine processing, showed functional value and potential for high-value usage which benefited from their rich polyphenols. In this study, the free and bound polyphenols from R. roxburghii DGs were extracted and their potential effect on modulating fecal microbiota was investigated using in vitro fecal fermentation. The free polyphenols (26.32-26.45 mg GAE/g) showed higher antioxidant activity compared to the bound polyphenols (8.76-9.01 mg GAE/g). The free and bound polyphenols significantly improved the fecal microbiota community structure and enhanced short chain fatty acids concentrations after the stimulated colonic fermentation for 24 h. Furthermore, the effect of R. roxburghii DGs polyphenols on modulating fecal microbiota was primarily attributed to quercetin, catechin, kaempferol, cyanidin and baicalin. This research suggests that R. roxburghii DGs are a promising source of natural antioxidants and prebiotic foods.

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