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1.
Nat Commun ; 15(1): 7000, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143095

RESUMO

Mutations in the nuclear envelope (NE) protein lamin A/C (encoded by LMNA), cause a severe form of dilated cardiomyopathy (DCM) with early-onset life-threatening arrhythmias. However, molecular mechanisms underlying increased arrhythmogenesis in LMNA-related DCM (LMNA-DCM) remain largely unknown. Here we show that a frameshift mutation in LMNA causes abnormal Ca2+ handling, arrhythmias and disformed NE in LMNA-DCM patient-specific iPSC-derived cardiomyocytes (iPSC-CMs). Mechanistically, lamin A interacts with sirtuin 1 (SIRT1) where mutant lamin A/C accelerates degradation of SIRT1, leading to mitochondrial dysfunction and oxidative stress. Elevated reactive oxygen species (ROS) then activates the Ca2+/calmodulin-dependent protein kinase II (CaMKII)-ryanodine receptor 2 (RYR2) pathway and aggravates the accumulation of SUN1 in mutant iPSC-CMs, contributing to arrhythmias and NE deformation, respectively. Taken together, the lamin A/C deficiency-mediated ROS disorder is revealed as central to LMNA-DCM development. Manipulation of impaired SIRT1 activity and excessive oxidative stress is a potential future therapeutic strategy for LMNA-DCM.


Assuntos
Cardiomiopatia Dilatada , Células-Tronco Pluripotentes Induzidas , Lamina Tipo A , Miócitos Cardíacos , Estresse Oxidativo , Espécies Reativas de Oxigênio , Sirtuína 1 , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/patologia , Lamina Tipo A/metabolismo , Lamina Tipo A/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Humanos , Sirtuína 1/metabolismo , Sirtuína 1/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fenótipo , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/genética , Arritmias Cardíacas/patologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Mutação da Fase de Leitura , Cálcio/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Membrana Nuclear/metabolismo , Mitocôndrias/metabolismo , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Associadas aos Microtúbulos/genética
2.
Front Endocrinol (Lausanne) ; 15: 1441997, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39175572

RESUMO

Background: Large-scale prospective cohort studies on diabetic foot ulcers risk factor screening in China are limited. Therefore, this prospective cohort study aimed to explore the predictive risk factors for diabetic foot ulcers to provide clinicians with concise and effective clinical indicators for identifying a high-risk diabetic foot and guiding the prevention of diabetic foot ulcers. Methods: Patients with diabetes who visited the Department of Endocrinology of Peking University First Hospital from October 2017 to December 2018 were selected as research participants by convenience sampling. A total of 968 patients were included. After enrollment, a dedicated person collected and recorded all baseline data. A dedicated telephone follow-up was conducted every 12-24 months to evaluate whether the endpoint event had occurred. All patients were followed up for an average of 61 (57-71) months, with 95% of them followed up for more than 60 months. According to the occurrence of endpoint events, they were divided into the DFU and non-DFU groups. The data between the two groups were analyzed using independent-sample t-test, Wilcoxon rank sum test, and chi square test. We used univariate and multivariate logistic regression analysis to analyze the factors that affected the occurrence of diabetic foot ulcers. Results and conclusions: After the 5-year follow-up, the incidence of diabetic foot was 25.83%. Multivariate logistic regression analysis revealed that body mass index (odds ratio: 1.046; 95% confidence interval: 1.001-1.093), abnormal pinprick sensation (odds ratio: 4.138; 95% confidence interval: 1.292-13.255), history of fungal foot infection (odds ratio: 2.287; 95% confidence interval: 1.517-3.448), abnormal 128-Hz tuning fork test (odds ratio: 2.628; 95% confidence interval: 1.098-6.294), and HbA1c≥ 8% (odds ratio: 1.522; 95% confidence interval: 1.014-2.284) were independent predictors of diabetic foot. Our study highlights clinically relevant indicators that may help to prevent the occurrence of diabetic foot and guide timely interventions.


Assuntos
Pé Diabético , Humanos , Pé Diabético/epidemiologia , Feminino , Masculino , Pessoa de Meia-Idade , Seguimentos , Fatores de Risco , Pequim/epidemiologia , Idoso , Estudos Prospectivos , Adulto , Prognóstico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia
3.
Stem Cell Reports ; 19(8): 1137-1155, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39094563

RESUMO

Cell size is a crucial physical property that significantly impacts cellular physiology and function. However, the influence of cell size on stem cell specification remains largely unknown. Here, we investigated the dynamic changes in cell size during the differentiation of human pluripotent stem cells into definitive endoderm (DE). Interestingly, cell size exhibited a gradual decrease as DE differentiation progressed with higher stiffness. Furthermore, the application of hypertonic pressure or chemical to accelerate the reduction in cell size significantly and specifically enhanced DE differentiation. By functionally intervening in mechanosensitive elements, we have identified actomyosin activity as a crucial mediator of both DE differentiation and cell size reduction. Mechanistically, the reduction in cell size induces actomyosin-dependent angiomotin (AMOT) nuclear translocation, which suppresses Yes-associated protein (YAP) activity and thus facilitates DE differentiation. Together, our study has established a novel connection between cell size diminution and DE differentiation, which is mediated by AMOT nuclear translocation. Additionally, our findings suggest that the application of osmotic pressure can effectively promote human endodermal lineage differentiation.


Assuntos
Actomiosina , Angiomotinas , Diferenciação Celular , Tamanho Celular , Endoderma , Transdução de Sinais , Fatores de Transcrição , Proteínas de Sinalização YAP , Humanos , Endoderma/citologia , Endoderma/metabolismo , Actomiosina/metabolismo , Proteínas de Sinalização YAP/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Pressão Osmótica , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/citologia , Núcleo Celular/metabolismo
4.
J Cell Mol Med ; 28(16): e70017, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39159071

RESUMO

Acute myeloid leukaemia (AML) is a common and highly aggressive haematological malignancy in adults. Senescence-associated secretory phenotype (SASP) plays important roles in tumorigenesis and progression of tumour. However, the prognostic value of SASP in patients with AML has not been clarified. The present study aims to explore the prognostic value of SASP and develop a prognostic risk signature for AML. The RNA-sequencing data was collected from the TCGA, GTEx and TARGET databases. Subsequently, differentially expressed gene analysis, univariate Cox regression and LASSO regression were applied to identified prognostic SASP-related genes and construct a prognostic risk-scoring model. The risk score of each patient were calculated and patients were divided into high- or low-risk groups by the median risk score. This novel prognostic signature included 11 genes: G6PD, CDK4, RPS6KA1, UBC, H2BC12, KIR2DL4, HSF1, IFIT3, PIM1, RUNX3 and TRIM21. The patients with AML in the high-risk group had shorter OS, demonstrating that the risk score acted as a prognostic predictor, which was validated in the TAGET-AML dataset. Univariate and multivariate analysis revealed the risk score was an independent prognostic factor in patients with AML. Furthermore, the present study revealed that the risk score was associated with immune landscape, immune checkpoint gene expression and chemotherapeutic efficacy. In the present study, we constructed and validated a unique SASP-related prognostic model to assess therapeutic effect and prognosis in patients with AML, which might contribute to understanding the role of SASP in AML and guiding the treatment for AML.


Assuntos
Biomarcadores Tumorais , Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/mortalidade , Prognóstico , Feminino , Biomarcadores Tumorais/genética , Masculino , Perfilação da Expressão Gênica , Pessoa de Meia-Idade , Regulação Leucêmica da Expressão Gênica , Transcriptoma/genética , Adulto , Fatores de Risco
5.
Ultrasonics ; 144: 107437, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39182432

RESUMO

To address the problem of the high hardware requirements and insufficient data storage capacity in current ultrasonic imaging testing, a novel approach is developed using a programmable device, which combines spatial-frequency parallel subsampling with the distributed compressive sensing simultaneous orthogonal matching pursuit (DCS-SOMP) algorithm to achieve fast and high-quality ultrasonic imaging inspection with a small amount of subsampled data. The spatial sparse measurement method was employed to achieve spatial subsampling and minimize the count of signals. Additionally, frequency subsampling was utilized to significantly reduce the data volume of time-domain signals while ensuring signal quality by truncating the primary testing frequency components. The subsampled data was then reconstructed using distributed compressive sensing (DCS) for multi-channel data reconstruction. The experiment of ultrasonic scanning imaging was conducted on a carbon steel specimen containing six transverse through-holes with a diameter of Ф1.5 mm at different depths. The ultrasonic signals were acquired using the spatial-frequency parallel subsampling method, and subsequently reconstructed using the DCS-SOMP algorithm. The results show that the proposed method achieves comparable image quality to that obtained with complete data, using only 1/8 of the complete data, while accurately locating and quantifying defects.

6.
Soft Matter ; 20(31): 6150-6159, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39044475

RESUMO

Liquid-liquid phase separation (LLPS) is the mechanism underlying the formation of bio-molecular condensates which are important compartments regulating intra- and extra-cellular functions. Electrostatic interactions are some of the important driving forces of the LLPS behaviors of biomolecules. However, the understanding of the electrostatic interactions is still limited, especially in the mixtures of biomolecules with different charge patterns. Here, we focus on the electrostatic interactions in mixtures of charge-asymmetric and charge-symmetric polyampholytes and their roles in the phase separation behaviors. We build charge-asymmetric and charge-symmetric model proteins consisting of both glutamic acid (E, negatively charged) and lysine (K, positively charged), i.e. polyampholytes of E35K15 (charge asymmetric) and E25K25 (charge symmetric). Pure E25K25 can undergo LLPS. To investigate the effects of charge-asymmetric polyampholytes on the mixtures of E25K25/E35K15, we perform coarse-grained simulations to determine their phase separation. The charge-asymmetric polyampholyte E35K15 is resistant to the LLPS of the mixtures of E25K25/E35K15. The condensate density decreases with the molar fraction of E35K15 increasing to 0.4, and no LLPS occurs at the molar fraction of 0.5 and above. This can be attributed to the electrostatic repulsion between the negatively charged E35K15 polymers. We further investigate the effects of charge asymmetry on the conformations and properties of the condensates. The E35K15 polymers in the condensates exhibit a more collapsed state as the molar fraction of E35K15 increases. However, the conformation of E25K25 polymers changes slightly across different condensates. The surface tensions of condensates decline with the increase of the molar fraction of E35K15 polymers, while the diffusivity of polymers in the condensed phases is enhanced. This work elucidates the role of charge-asymmetric polyampholytes in determining the LLPS behaviours of binary mixtures of charge-symmetric and charge-asymmetric proteins as well as the properties of condensed phases.

7.
Chem Commun (Camb) ; 60(66): 8748-8751, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39073077

RESUMO

The integration of anionic Ti4L6 (L = embonate) cages and π-conjugated coordination cations into ordered structures can produce high-performance nonlinear optical (NLO) materials. More specifically, by employing Ti4L6 cages for assembly with mixed N,N-chelated and P,P-chelated type conjugated organic ligands and Ag+ ions, three cage-based structures have been synthesized and structurally characterized. Among them, an ion pair structure with strong π-π accumulation exhibits a significant third-order NLO response, and an excellent optical limiting effect has been experimentally verified. This work provides a promising material for NLO applications.

8.
Macromolecules ; 57(14): 6449-6464, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39071044

RESUMO

We investigated the temperature-dependent structural evolution of thermoreversible triblock terpolypeptoid hydrogels, namely poly(N-allyl glycine)-b-poly(N-methyl glycine)-b-poly(N-decyl glycine) (AMD), using small-angle neutron scattering (SANS) with contrast matching in conjunction with X-ray scattering and cryogenic transmission electron microscopy (cryo-TEM) techniques. At room temperature, A100M101D10 triblock terpolypeptoids self-assemble into core-corona-type spherical micelles in aqueous solution. Upon heating above the critical gelation temperature (T gel), SANS analysis revealed the formation of a two-compartment hydrogel network comprising distinct micellar cores composed of dehydrated A blocks and hydrophobic D blocks. At T ≳ T gel, the temperature-dependent dehydration of A block further leads to the gradual rearrangement of both A and D domains, forming well-ordered micellar network at higher temperatures. For AMD polymers with either longer D block or shorter A block, such as A101M111D21 and A43M92D9, elongated nonspherical micelles with a crystalline D core were observed at T < T gel. Although these enlarged crystalline micelles still undergo a sharp sol-to-gel transition upon heating, the higher aggregation number of chains results in the immediate association of the micelles into ordered aggregates at the initial stage, followed by a disruption of the spatial ordering as the temperature further increases. On the other hand, fiber-like structures were also observed for AMD with longer A block, such as A153M127D10, due to the crystallization of A domains. This also influences the assembly pathway of the two-compartment network. Our findings emphasize the critical impact of initial micellar morphology on the structural evolution of AMD hydrogels during the sol-to-gel transition, providing valuable insights for the rational design of thermoresponsive hydrogels with tunable network structures at the nanometer scale.

9.
Nat Commun ; 15(1): 5627, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965283

RESUMO

Glycosphingolipids (GSLs) are essential components of cell membranes, particularly enriched in the nervous system. Altered molecular distributions of GSLs are increasingly associated with human diseases, emphasizing the significance of lipidomic profiling. Traditional GSL analysis methods are hampered by matrix effect from phospholipids and the difficulty in distinguishing structural isomers. Herein, we introduce a highly sensitive workflow that harnesses magnetic TiO2 nanoparticle-based selective enrichment, charge-tagging Paternò-Büchi reaction, and liquid chromatography-tandem mass spectrometry. This approach enables mapping over 300 distinct GSLs in brain tissues by defining sugar types, long chain bases, N-acyl chains, and the locations of desaturation and hydroxylation. Relative quantitation of GSLs across multiple structural levels provides evidence of dysregulated gene and protein expressions of FA2H and CerS2 in human glioma tissue. Based on the structural features of GSLs, our method accurately differentiates human glioma with/without isocitrate dehydrogenase genetic mutation, and normal brain tissue.


Assuntos
Encéfalo , Glioma , Glicoesfingolipídeos , Humanos , Glicoesfingolipídeos/metabolismo , Glicoesfingolipídeos/química , Glioma/metabolismo , Glioma/genética , Glioma/patologia , Encéfalo/metabolismo , Lipidômica/métodos , Espectrometria de Massas em Tandem/métodos , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Cromatografia Líquida/métodos , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Animais , Camundongos
10.
J Biomed Mater Res A ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007419

RESUMO

As the cornerstone of tissue engineering and regeneration medicine research, developing a cost-effective and bionic extracellular matrix (ECM) that can precisely modulate cellular behavior and form functional tissue remains challenging. An artificial ECM combining polysaccharides and fibrillar proteins to mimic the structure and composition of natural ECM provides a promising solution for cardiac tissue regeneration. In this study, we developed a bionic hydrogel scaffold by combining a quaternized ß-chitin derivative (QC) and fibrin-matrigel (FM) in different ratios to mimic a natural ECM. We evaluated the stiffness of those composite hydrogels with different mixing ratios and their effects on the growth of human umbilical vein endothelial cells (HUVECs). The optimal hydrogels, QCFM1 hydrogels were further applied to load HUVECs into nude mice for in vivo angiogenesis. Besides, we encapsulated human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) into QCFM hydrogels and employed 3D bioprinting to achieve batch fabrication of human-engineered heart tissue (hEHT). Finally, the myocardial structure and electrophysiological function of hEHT were evaluated by immunofluorescence and optical mapping. Designed artificial ECM has a tunable modulus (220-1380 Pa), which determines the different cellular behavior of HUVECs when encapsulated in these. QCFM1 composite hydrogels with optimal stiffness (800 Pa) and porous architecture were finally identified, which could adapt for in vitro cell spreading and in vivo angiogenesis of HUVECs. Moreover, QCFM1 hydrogels were applied in 3D bioprinting successfully to achieve batch fabrication of both ring-shaped and patch-shaped hEHT. These QCFM1 hydrogels-based hEHTs possess organized sarcomeres and advanced function characteristics comparable to reported hEHTs. The chitin-derived hydrogels are first used for cardiac tissue engineering and achieve the batch fabrication of functionalized artificial myocardium. Specifically, these novel QCFM1 hydrogels provided a reliable and economical choice serving as ideal ECM for application in tissue engineering and regeneration medicine.

11.
Mater Horiz ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39082084

RESUMO

Preservation of mitochondrial functionality is essential for heart hemostasis and cardiovascular diseases treatment. However, the current nanomedicines including liposomes, polymers and inorganic nanomaterials are severely hindered by poor stability, high manufacturing costs and potential biotoxicity. In this research, we present novel polyphenolic nanoparticles (NPs) derived from naturally occurring pomegranate peel (PP, labelled as PPP NPs), which exhibit potent antioxidative and anti-inflammatory properties, serving as a modulator of mitochondrial function. PPP NPs have been identified to improve survival rates in models of mitochondrial depletion through enhancement of cardiomyocyte proliferation and the reduction of DNA damage. Moreover, PPP NPs can effectively inhibit the production of reactive oxygen species and inflammatory mediators in lipopolysaccharide (LPS)-induced mitochondrial damage. Utilizing human engineered heart tissue and mice models, PPP NPs were found to significantly improve contractile function and alleviate inflammation activities after LPS treatment. Mechanically, PPP NPs regulated inflammatory responses via a m6A dependent manner, as determined using RNA-seq and MeRIP-seq analyses. Collectively, these insights underscore the potential of PPP NPs as a novel therapeutic approach for mitochondrial dysfunction.

12.
Sci Rep ; 14(1): 14695, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926501

RESUMO

A facile and environmentally friendly ion exchange-assisted surface passivation (IASP) strategy is presented for synthesizing red emitting Mn4+-activated fluoride phosphors. A substantial, pristine Mn4+-free shell layer, applied as a coating to Mn4+ doped potassium fluorosilicate K2SiF6:Mn4+ (KSFM) phosphors, enhances both water resistance and luminescence efficiency. The stability test of fluoride in water at ambient temperature and boiling water demonstrates that IASP-treated KSFM phosphors are highly water resistant. Furthermore, both the negative thermal temperature (NTQ) fitting results and the photoluminescence (PL) decay confirm that the IASP process effectively passivates surface defects, leading to enhanced luminescence performance. The maximum internal quantum yield (QYi) of the IASP-KSFM phosphor is 94.24%. A white LED realized a high color rendering index (CRI) of 93.09 and luminous efficiency (LE) of 149.48 lm/W. This work presented a novel technique for the development of stable fluoride phosphors and has the potential to increase the use of KSFM phosphors in plant supplementary lighting systems and white light-emitting diodes.

13.
Chembiochem ; 25(16): e202400316, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-38867605

RESUMO

With the increasing use of polyethylene glycol (PEG) based proteins and drug delivery systems, anti-PEG antibodies have commonly been detected among the population, causing the accelerated blood clearance and hypersensitivity reactions, poses potential risks to the clinical efficacy and safety of PEGylated drugs. Therefore, vigilant monitoring of anti-PEG antibodies is crucial for both research and clinical guidance regarding PEGylated drugs. The enzyme-linked immunosorbent assay (ELISA) is a common method for detecting anti-PEG antibodies. However, diverse coating methods, blocking solutions and washing solutions have been employed across different studies, and unsuitable use of Tween 20 as the surfactant even caused biased results. In this study, we established the optimal substrate coating conditions, and investigated the influence of various surfactants and blocking solutions on the detection accuracy. The findings revealed that incorporating 1 % bovine serum albumin into the serum dilution in the absence of surfactants will result the credible outcomes of anti-PEG antibody detection.


Assuntos
Anticorpos , Ensaio de Imunoadsorção Enzimática , Polietilenoglicóis , Polietilenoglicóis/química , Anticorpos/imunologia , Anticorpos/química , Soroalbumina Bovina/química , Soroalbumina Bovina/imunologia , Animais , Tensoativos/química , Humanos , Polissorbatos/química
14.
Molecules ; 29(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38930975

RESUMO

As a toxic Volatile Organic Pollutant (TVOC), formaldehyde has a toxic effect on microorganisms, consequently inhibiting the biochemical process of formaldehyde wastewater treatment. Therefore, the selective degradation of formaldehyde is of great significance in achieving high-efficiency and low-cost formaldehyde wastewater treatment. This study constructed a heterogeneous Fe-ZSM-5/H2O2 Fenton system f or the selective degradation of target compounds. By immobilizing Fe3+ onto the surface of a ZSM-5 molecular sieve, Fe-ZSM-5 was prepared successfully. XRD, BET and FT-IR spectral studies showed that Fe-ZSM-5 was mainly composed of micropores. The influences of different variables on formaldehyde-selective heterogeneous Fenton degradation performance were studied. The 93.7% formaldehyde degradation and 98.2% selectivity of formaldehyde compared with glucose were demonstrated in the optimized Fenton system after 360 min. Notably, the resultant selective Fenton oxidation system had a wide range of pH suitability, from 3.0 to 10.0. Also, the Fe-ZSM-5 was used in five consecutive cycles without a significant drop in formaldehyde degradation efficiency. The use of reactive oxygen species scavengers indicated that the hydroxyl radical was the primary active species responsible for degrading formaldehyde. Furthermore, great degradation performance was acquired with high concentrations of formaldehyde for this system, and the degradation efficiency was more than 95.0%.

15.
J Nanobiotechnology ; 22(1): 378, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943185

RESUMO

Tissue engineered heart valves (TEHVs) demonstrates the potential for tissue growth and remodel, offering particular benefit for pediatric patients. A significant challenge in designing functional TEHV lies in replicating the anisotropic mechanical properties of native valve leaflets. To establish a biomimetic TEHV model, we employed melt-electrowriting (MEW) technology to fabricate an anisotropic PCL scaffold. By integrating the anisotropic MEW-PCL scaffold with bioactive hydrogels (GelMA/ChsMA), we successfully crafted an elastic scaffold with tunable mechanical properties closely mirroring the structure and mechanical characteristics of natural heart valves. This scaffold not only supports the growth of valvular interstitial cells (VICs) within a 3D culture but also fosters the remodeling of extracellular matrix of VICs. The in vitro experiments demonstrated that the introduction of ChsMA improved the hemocompatibility and endothelialization of TEHV scaffold. The in vivo experiments revealed that, compared to their non-hydrogel counterparts, the PCL-GelMA/ChsMA scaffold, when implanted into SD rats, significantly suppressed immune reactions and calcification. In comparison with the PCL scaffold, the PCL-GelMA/ChsMA scaffold exhibited higher bioactivity and superior biocompatibility. The amalgamation of MEW technology and biomimetic design approaches provides a new paradigm for manufacturing scaffolds with highly controllable microstructures, biocompatibility, and anisotropic mechanical properties required for the fabrication of TEHVs.


Assuntos
Valvas Cardíacas , Hidrogéis , Ratos Sprague-Dawley , Engenharia Tecidual , Alicerces Teciduais , Engenharia Tecidual/métodos , Animais , Alicerces Teciduais/química , Anisotropia , Ratos , Hidrogéis/química , Materiais Biocompatíveis/química , Próteses Valvulares Cardíacas , Poliésteres/química , Células Cultivadas , Humanos , Matriz Extracelular/química , Masculino
16.
Exp Cell Res ; 440(2): 114148, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38936760

RESUMO

UBA5, a ubiquitin-like activated enzyme involved in ufmylation and sumoylation, presents a viable target for pancreatic and breast cancer treatments, yet its role in lung adenocarcinoma (LUAD) remains underexplored. This study reveals UBA5's tumor-promoting effect in LUAD, as evidenced by its upregulation in patients and positive correlation with TNM stages. Elevated UBA5 levels predict poor outcomes for these patients. Pharmacological inhibition of UBA5 using DKM 2-93 significantly curtails the growth of A549, H1299, and cisplatin-resistant A549 (A549/DDP) LUAD cells in vitro. Additionally, UBA5 knockdown via shRNA lentivirus suppresses tumor growth both in vitro and in vivo. High UBA5 expression adversely alters the tumor immune microenvironment, affecting immunostimulators, MHC molecules, chemokines, receptors, and immune cell infiltration. Notably, UBA5 expression correlates positively with M2 macrophage infiltration, the predominant immune cells in LUAD. Co-culture experiments further demonstrate that UBA5 knockdown directly inhibits M2 macrophage polarization and lactate production in LUAD. Moreover, in vivo studies show reduced M2 macrophage infiltration following UBA5 knockdown. UBA5 expression is also associated with increased tumor heterogeneity, including tumor mutational burden, microsatellite instability, neoantigen presence, and homologous recombination deficiency. Experiments indicate that UBA5 overexpression promotes cisplatin resistance in vitro, whereas UBA5 inhibition enhances cisplatin sensitivity in both in vitro and in vivo settings. Overall, these findings suggest that targeting UBA5 inhibits LUAD by impeding cancer cell proliferation, M2 macrophage polarization, and cisplatin resistance.


Assuntos
Adenocarcinoma de Pulmão , Cisplatino , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares , Humanos , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Animais , Camundongos , Proliferação de Células/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Enzimas Ativadoras de Ubiquitina/metabolismo , Enzimas Ativadoras de Ubiquitina/genética , Enzimas Ativadoras de Ubiquitina/antagonistas & inibidores , Feminino , Microambiente Tumoral/efeitos dos fármacos , Camundongos Nus , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Masculino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos
17.
Toxicology ; 506: 153850, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38821196

RESUMO

Fine particulate matter (PM2.5)-induced metabolic disorders have attracted increasing attention, however, the underlying molecular mechanism of PM2.5-induced hepatic bile acid disorder remains unclear. In this study, we investigated the effects of PM2.5 components on the disruption of bile acid in hepatocytes through farnesoid X receptor (FXR) pathway. The receptor binding assays showed that PM2.5 extracts bound to FXR directly, with half inhibitory concentration (IC50) value of 21.7 µg/mL. PM2.5 extracts significantly promoted FXR-mediated transcriptional activity at 12.5 µg/mL. In mouse primary hepatocytes, we found PM2.5 extracts (100 µg/mL) significantly decreased the total bile acid levels, inhibited the expression of bile acid synthesis gene (Cholesterol 7 alpha-hydroxylase, Cyp7a1), and increased the expression of bile acid transport genes (Multidrug resistance associated protein 2, Abcc2; and Bile salt export pump, Abcb11). Moreover, these alterations were significantly attenuated by knocking down FXR in hepatocytes. We further divided the organic components and water-soluble components from PM2.5, and found that two components bound to and activated FXR, and decreased the bile acid levels in hepatocytes. In addition, benzo[a]pyrene (B[a]P) and cadmium (Cd) were identified as two bioactive components in PM2.5-induced bile acid disorders through FXR signaling pathway. Overall, we found PM2.5 components could bind to and activate FXR, thereby disrupting bile acid synthesis and transport in hepatocytes. These new findings also provide new insights into PM2.5-induced toxicity through nuclear receptor pathways.


Assuntos
Ácidos e Sais Biliares , Hepatócitos , Material Particulado , Receptores Citoplasmáticos e Nucleares , Animais , Humanos , Masculino , Camundongos , Ácidos e Sais Biliares/metabolismo , Células Cultivadas , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Homeostase/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Material Particulado/toxicidade , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/efeitos dos fármacos
18.
Artigo em Inglês | MEDLINE | ID: mdl-38600661

RESUMO

High-voltage resistant quasi-solid-state polymer electrolytes (QSPEs) are promising for enhancing the energy density of lithium-metal batteries in practice. However, side reactions occurring at the interfaces between the anodes or cathodes and QSPEs considerably reduce the lifespan of high-voltage LMBs. In this study, a copolymer of vinyl ethylene carbonate (VEC) and poly(ethylene glycol) diacrylate (PEGDA) was used as the framework, with a cellulose membrane (CE) as the supporting layer. Based on density functional theory calculations, 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (Pyr14TFSI), an ionic liquid, was screened because of its lowest unoccupied molecular orbital energy level as a modifying agent for the in situ P(VECx-EGy)/Pyrz/LiTFSI@CE QSPEs synthesis. Pyr14+, with a lithiophobic alkyl chain, forms a dense positive ion shielding layer on the protruding tips of deposited lithium, facilitating uniform and smooth lithium deposition. Pyr14TFSI assists in constructing a stable solid electrolyte interphase (SEI) layer on the Li surface enriched with LiF, Li3N, and RCOOLi. The modulation of lithium deposition behavior on the anode by Pyr14TFSI ensures stable Li plating/stripping for >1500 h. A Li-Cu cell exhibits stable cycling for >200 cycles at a current density of 0.05 mA cm-2, with an average Coulombic efficiency of 92.7%. In situ polymerization ensures that P(VECx-EGy)/Pyrz/LiTFSI@CE QSPEs exhibit excellent interface compatibility with the anode and the cathode. The CR2032 button cell Li|P(VEC1-EG0.06)/Pyr0.4/LiTFSI@CE|LiCoO2 demonstrates stable cycling with a negligible capacity decay of 0.083% per cycle for >390 cycles at 25 °C and 0.2 C when using a high-voltage LiCoO2 (4.45 V) cathode. Furthermore, a 7.1 mAh pouch cell achieves stable charge-discharge cycles, confirming the pronounced stability of the as-fabricated QSPE at the interfaces of the high-voltage LiCoO2 cathode and Li anode.

19.
Sensors (Basel) ; 24(5)2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38475188

RESUMO

Hyperspectral anomaly detection is used to recognize unusual patterns or anomalies in hyperspectral data. Currently, many spectral-spatial detection methods have been proposed with a cascaded manner; however, they often neglect the complementary characteristics between the spectral and spatial dimensions, which easily leads to yield high false alarm rate. To alleviate this issue, a spectral-spatial information fusion (SSIF) method is designed for hyperspectral anomaly detection. First, an isolation forest is exploited to obtain spectral anomaly map, in which the object-level feature is constructed with an entropy rate segmentation algorithm. Then, a local spatial saliency detection scheme is proposed to produce the spatial anomaly result. Finally, the spectral and spatial anomaly scores are integrated together followed by a domain transform recursive filtering to generate the final detection result. Experiments on five hyperspectral datasets covering ocean and airport scenes prove that the proposed SSIF produces superior detection results over other state-of-the-art detection techniques.

20.
Science ; 383(6684): 746-750, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38359138

RESUMO

Chemical reactions are generally assumed to proceed from reactants to products along the minimum energy path (MEP). However, straying from the MEP-roaming-has been recognized as an unconventional reaction mechanism and found to occur in both the ground and first excited states. Its existence in highly excited states is however not yet established. We report a dissociation channel to produce electronically excited fragments, S(1D)+O2(a1Δg), from SO2 photodissociation in highly excited states. The results revealed two dissociation pathways: One proceeds through the MEP to produce vibrationally colder O2(a1Δg) and the other yields vibrationally hotter O2(a1Δg) by means of a roaming pathway involving an intramolecular O abstraction during reorientation motion. Such roaming dynamics may well be the rule rather than the exception for molecular photodissociation through highly excited states.

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