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Tumor-derived extracellular vesicles are important mediators of cell-to-cell communication during tumorigenesis. Here, we demonstrated that hepatocellular carcinoma (HCC)-derived ectosomes remodel the tumor microenvironment to facilitate HCC progression in an ectosomal PKM2-dependent manner. HCC-derived ectosomal PKM2 induced not only metabolic reprogramming in monocytes but also STAT3 phosphorylation in the nucleus to upregulate differentiation-associated transcription factors, leading to monocyte-to-macrophage differentiation and tumor microenvironment remodeling. In HCC cells, sumoylation of PKM2 induced its plasma membrane targeting and subsequent ectosomal excretion via interactions with ARRDC1. The PKM2-ARRDC1 association in HCC was reinforced by macrophage-secreted cytokines/chemokines in a CCL1-CCR8 axis-dependent manner, further facilitating PKM2 excretion from HCC cells to form a feedforward regulatory loop for tumorigenesis. In the clinic, ectosomal PKM2 was clearly detected in the plasma of HCC patients. This study highlights a mechanism by which ectosomal PKM2 remodels the tumor microenvironment and reveals ectosomal PKM2 as a potential diagnostic marker for HCC.
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Proteínas de Transporte/metabolismo , Micropartículas Derivadas de Células/metabolismo , Proteínas de Membrana/metabolismo , Hormônios Tireóideos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proteínas de Transporte/genética , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Micropartículas Derivadas de Células/genética , Micropartículas Derivadas de Células/patologia , Quimiocina CCL1/metabolismo , Progressão da Doença , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Macrófagos/metabolismo , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Monócitos/metabolismo , Prognóstico , Fator de Transcrição STAT3/metabolismo , Hormônios Tireóideos/genética , Microambiente Tumoral , Proteínas de Ligação a Hormônio da TireoideRESUMO
Plant inflorescence architecture is determined by inflorescence meristem (IM) activity and controlled by genetic mechanisms associated with environmental factors. In Arabidopsis (Arabidopsis thaliana), TERMINAL FLOWER1 (TFL1) is expressed in the IM and is required to maintain indeterminate growth, whereas LEAFY (LFY) is expressed in the floral meristems (FMs) formed at the periphery of the IM and is required to activate determinate floral development. Here, we address how Arabidopsis indeterminate inflorescence growth is determined. We show that the 26S proteasome subunit REGULATORY PARTICLE AAA-ATPASE 2a (RPT2a) is required to maintain the indeterminate inflorescence architecture in Arabidopsis. rpt2a mutants display reduced TFL1 expression levels and ectopic LFY expression in the IM and develop a determinate zigzag-shaped inflorescence. We further found that RPT2a promotes DNA METHYLTRANSFERASE1 degradation, leading to DNA hypomethylation upstream of TFL1 and high TFL1 expression levels in the wild-type IM. Overall, our work reveals that proteolytic input into the epigenetic regulation of TFL1 expression directs inflorescence architecture in Arabidopsis, adding an additional layer to stem cell regulation.
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NKG2D (natural-killer group 2, member D) is a homodimeric transmembrane receptor that plays an important role in NK, γδ+, and CD8+ T cell-mediated immune responses to environmental stressors such as viral or bacterial infections and oxidative stress. However, aberrant NKG2D signaling has also been associated with chronic inflammatory and autoimmune diseases, and as such NKG2D is thought to be an attractive target for immune intervention. Here, we describe a comprehensive small-molecule hit identification strategy and two distinct series of protein-protein interaction inhibitors of NKG2D. Although the hits are chemically distinct, they share a unique allosteric mechanism of disrupting ligand binding by accessing a cryptic pocket and causing the two monomers of the NKG2D dimer to open apart and twist relative to one another. Leveraging a suite of biochemical and cell-based assays coupled with structure-based drug design, we established tractable structure-activity relationships with one of the chemical series and successfully improved both the potency and physicochemical properties. Together, we demonstrate that it is possible, albeit challenging, to disrupt the interaction between NKG2D and multiple protein ligands with a single molecule through allosteric modulation of the NKG2D receptor dimer/ligand interface.
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Células Matadoras Naturais , Subfamília K de Receptores Semelhantes a Lectina de Células NK , Ligantes , Linfócitos T CD8-Positivos , Ligação ProteicaRESUMO
Metabolites such as crotonyl-CoA and lactyl-CoA influence gene expression by covalently modifying histones, known as histone lysine crotonylation (Kcr) and lysine lactylation (Kla). However, the existence patterns, dynamic changes, biological functions and associations of these modifications with histone lysine acetylation and gene expression during mammalian development remain largely unknown. Here, we find that histone Kcr and Kla are widely distributed in the brain and undergo global changes during neural development. By profiling the genome-wide dynamics of H3K9ac, H3K9cr and H3K18la in combination with ATAC and RNA sequencing, we reveal that these marks are tightly correlated with chromatin state and gene expression, and extensively involved in transcriptome remodeling to promote cell-fate transitions in the developing telencephalon. Importantly, we demonstrate that global Kcr and Kla levels are not the consequence of transcription and identify the histone deacetylases (HDACs) 1-3 as novel 'erasers' of H3K18la. Using P19 cells as an induced neural differentiation system, we find that HDAC1-3 inhibition by MS-275 pre-activates neuronal transcriptional programs by stimulating multiple histone lysine acylations simultaneously. These findings suggest that histone Kcr and Kla play crucial roles in the epigenetic regulation of neural development.
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Histonas , Lisina , Acetilação , Animais , Epigênese Genética , Histonas/metabolismo , Lisina/metabolismo , Mamíferos/metabolismo , Processamento de Proteína Pós-TraducionalRESUMO
Precision medicine depends on high-accuracy individual-level genotype data. However, the whole-genome sequencing (WGS) is still not suitable for gigantic studies due to budget constraints. It is particularly important to construct highly accurate haplotype reference panel for genotype imputation. In this study, we used 10 000 samples with medium-depth WGS to construct a reference panel that we named the CKB reference panel. By imputing microarray datasets, it showed that the CKB panel outperformed compared panels in terms of both the number of well-imputed variants and imputation accuracy. In addition, we have completed the imputation of 100 706 microarrays with the CKB panel, and the after-imputed data is the hitherto largest whole genome data of the Chinese population. Furthermore, in the GWAS analysis of real phenotype height, the number of tested SNPs tripled and the number of significant SNPs doubled after imputation. Finally, we developed an online server for offering free genotype imputation service based on the CKB reference panel (https://db.cngb.org/imputation/). We believe that the CKB panel is of great value for imputing microarray or low-coverage genotype data of Chinese population, and potentially mixed populations. The imputation-completed 100 706 microarray data are enormous and precious resources of population genetic studies for complex traits and diseases.
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Bancos de Espécimes Biológicos , Genoma , Humanos , Haplótipos , Genótipo , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , ChinaRESUMO
Electrophilic addition of alkenes is a textbook reaction that plays a pivotal role in organic chemistry. In the past decades, catalytic asymmetric variants of this important type of reaction have witnessed great achievements by the development of novel catalytic systems. However, enantioselective aza-electrophilic additions of unactivated alkenes, which could provide a transformative strategy for the preparation of synthetically significant nitrogen-containing compounds, still remain a formidable challenge. Herein, we have developed unprecedented Au(I)/NHC-catalyzed asymmetric aza-electrophilic additions of unactivated 1,1-disubstituted styrenes by the utilization of readily available dialkyl azodicarboxylates as electrophilic nitrogen sources. Based on this approach, a series of transformations, including [2 + 2] cycloaddition, intermolecular 1,2-oxyamination, and several types of intramolecular hydrazination-induced cyclizations, have been realized. These transformations provide a previously unattainable platform for the divergent synthesis of hydrazine derivatives, which could also be converted to other nitrogen-containing chiral synthons. Experimental and computational studies support the idea that carbocation intermediates are involved in reaction pathways.
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Here, we describe a cooperative Pd(0)/chiral phosphoric acid catalytic system that allows us to realize the first chemo-, regio-, and enantioselective sequential cross-[4 + 2]-cycloaddition/decarboxylation reaction between 2-pyrones and unactivated acyclic 1,3-dienes. The key to the success of this transformation is the utilization of an achiral N-heterocyclic carbene (NHC) as the ligand and a newly developed chiral phosphoric acid as the cocatalyst. Experimental investigations and computational studies support the idea that the Pd(0)/NHC complex acts as a π-Lewis base to increase the nucleophilicity of 1,3-dienes via η2 coordination, while the chiral phosphoric acid simultaneously increases the electrophilicity of 2-pyrones by hydrogen bonding. By this synergistic catalysis, the sequential cross-[4 + 2]-cycloaddition and decarboxylation reaction proceeds efficiently, enabling the preparation of a wide range of chiral vinyl-substituted 1,3-cyclohexadienes in good yields and enantioselectivities. The synthetic utility of this reaction is demonstrated by synthetic transformations of the product to various valuable chiral six-membered carbocycles.
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The proportion of lung cancer in never smokers is rising, especially among Asian women, but there is no effective early detection tool. Here, we developed a polygenic risk score (PRS), which may help to identify the population with higher risk of lung cancer in never-smoking women. We first performed a large GWAS meta-analysis (8595 cases and 8275 controls) to systematically identify the susceptibility loci for lung cancer in never-smoking Asian women and then generated a PRS using GWAS datasets. Furthermore, we evaluated the utility and effectiveness of PRS in an independent Chinese prospective cohort comprising 55 266 individuals. The GWAS meta-analysis identified eight known loci and a novel locus (5q11.2) at the genome-wide statistical significance level of P < 5 × 10-8 . Based on the summary statistics of GWAS, we derived a polygenic risk score including 21 variants (PRS-21) for lung cancer in never-smoking women. Furthermore, PRS-21 had a hazard ratio (HR) per SD of 1.29 (95% CI = 1.18-1.41) in the prospective cohort. Compared with participants who had a low genetic risk, those with an intermediate (HR = 1.32, 95% CI: 1.00-1.72) and high (HR = 2.09, 95% CI: 1.56-2.80) genetic risk had a significantly higher risk of incident lung cancer. The addition of PRS-21 to the conventional risk model yielded a modest significant improvement in AUC (0.697 to 0.711) and net reclassification improvement (24.2%). The GWAS-derived PRS-21 significantly improves the risk stratification and prediction accuracy for incident lung cancer in never-smoking Asian women, demonstrating the potential for identification of high-risk individuals and early screening.
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Neoplasias Pulmonares , Humanos , Feminino , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/genética , Estratificação de Risco Genético , Predisposição Genética para Doença , Estudos de Coortes , Estudos Prospectivos , Estudo de Associação Genômica Ampla , Fatores de Risco , Fumar/genética , Fumar/epidemiologia , ChinaRESUMO
Cadaverine is an endogenous metabolite produced by the gut microbiome with various activity in physiological and pathological conditions. However, whether cadaverine regulates pain or itch remains unclear. In this study, we first found that cadaverine may bind to histamine 4 receptor (H4R) with higher docking energy score using molecular docking simulations, suggesting cadaverine may act as an endogenous ligand for H4R. We subsequently found intradermal injection of cadaverine into the nape or cheek of mice induces a dose-dependent scratching response in mice, which was suppressed by a selective H4R antagonist JNJ-7777120, transient receptor potential vanilloid 1 (TRPV1) antagonist capsazepine and PLC inhibitor U73122, but not H1R antagonist or TRPA1 antagonist or TRPV4 antagonist. Consistently, cadaverine-induced itch was abolished in Trpv1-/- but not Trpa1-/- mice. Pharmacological analysis indicated that mast cells and opioid receptors were also involved in cadaverine-induced itch in mice. scRNA-Seq data analysis showed that H4R and TRPV1 are mainly co-expressed on NP2, NP3 and PEP1 DRG neurons. Calcium imaging analysis showed that cadaverine perfusion enhanced calcium influx in the dissociated dorsal root ganglion (DRG) neurons, which was suppressed by JNJ-7777120 and capsazepine, as well as in the DRG neurons from Trpv1-/- mice. Patch-clamp recordings found that cadaverine perfusion significantly increased the excitability of small diameter DRG neurons, and JNJ-7777120 abolished this effect, indicating involvement of H4R. Together, these results provide evidences that cadaverine is a novel endogenous pruritogens, which activates H4R/TRPV1 signaling pathways in the primary sensory neurons.
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Cadaverina , Gânglios Espinais , Camundongos Endogâmicos C57BL , Prurido , Canais de Cátion TRPV , Animais , Prurido/metabolismo , Prurido/induzido quimicamente , Canais de Cátion TRPV/metabolismo , Gânglios Espinais/metabolismo , Gânglios Espinais/efeitos dos fármacos , Masculino , Cadaverina/análogos & derivados , Cadaverina/farmacologia , Cadaverina/metabolismo , Camundongos , Camundongos Knockout , Humanos , Mastócitos/metabolismo , Mastócitos/efeitos dos fármacos , Canal de Cátion TRPA1/metabolismo , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismo , Capsaicina/análogos & derivadosRESUMO
BACKGROUND & AIMS: Evidence is sparse and inconclusive on the association between long-term fine (≤2.5 µm) particulate matter (PM2.5) exposure and esophageal cancer. We aimed to assess the association of PM2.5 with esophageal cancer risk and compared the esophageal cancer risk attributable to PM2.5 exposure and other established risk factors. METHODS: This study included 510,125 participants without esophageal cancer at baseline from China Kadoorie Biobank. A high-resolution (1 × 1 km) satellite-based model was used to estimate PM2.5 exposure during the study period. Hazard ratios (HR) and 95% CIs of PM2.5 with esophageal cancer incidence were estimated using Cox proportional hazard model. Population attributable fractions for PM2.5 and other established risk factors were estimated. RESULTS: There was a linear concentration-response relationship between long-term PM2.5 exposure and esophageal cancer. For each 10-µg/m3 increase in PM2.5, the HR was 1.16 (95% CI, 1.04-1.30) for esophageal cancer incidence. Compared with the first quarter of PM2.5 exposure, participants in the highest quarter had a 1.32-fold higher risk for esophageal cancer, with an HR of 1.32 (95% CI, 1.01-1.72). The population attributable risk because of annual average PM2.5 concentration ≥35 µg/m3 was 23.3% (95% CI, 6.6%-40.0%), higher than the risks attributable to lifestyle risk factors. CONCLUSIONS: This large prospective cohort study of Chinese adults found that long-term exposure to PM2.5 was associated with an elevated risk of esophageal cancer. With stringent air pollution mitigation measures in China, a large reduction in the esophageal cancer disease burden can be expected.
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Neoplasias Esofágicas , Material Particulado , Adulto , Humanos , População do Leste Asiático , Exposição Ambiental/efeitos adversos , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/etiologia , Incidência , Material Particulado/efeitos adversos , Material Particulado/classificação , Estudos Prospectivos , China/epidemiologia , Fatores de RiscoRESUMO
BACKGROUND: Myocardial infarction (MI) dramatically changes the mechanical stress, which is intensified by the fibrotic remodeling. Integrins, especially the αV subunit, mediate mechanical signal and mechanoparacrine of transforming growth factor ß1 (TGF-ß1) in various organ fibrosis by activating CFs into myofibroblasts (MFBs). We investigated a possible role of integrin αV mediated mechanoparacrine of TGF-ß1 in MFBs activation for fibrous reparation in mice with MI. METHODS: Heart samples from MI, sham, or MI plus cilengitide (14 mg/kg, specific integrin αV inhibitor) treated mice, underwent functional and morphological assessments by echocardiography, and histochemistry on 7, 14 and 28 days post-surgery. The mechanical and ultrastructural changes of the fibrous scar were further evaluated by atomic mechanics microscope (AFM), immunofluorescence, second harmonic generation (SHG) imaging, polarized light and scanning electron microscope, respectively. Hydroxyproline assay was used for total collagen content, and western blot for protein expression profile examination. Fibroblast bioactivities, including cell shape, number, Smad2/3 signal and expression of extracellular matrix (ECM) related proteins, were further evaluated by microscopic observation and immunofluorescence in polyacrylamide (PA) hydrogel with adjustable stiffness, which was re-explored in fibroblast cultured on stiff matrix after silencing of integrin αV. The content of total and free TGF-ß1 was tested by enzyme-linked immunosorbent assay (ELISA) in both infarcted tissue and cell samples. RESULT: Increased stiffness with heterogeneity synchronized with integrin αV and alpha smooth muscle actin (α-SMA) positive MFBs accumulation in those less mature fibrous areas. Cilengitide abruptly reduced collagen content and disrupted collagen alignment, which also decreased TGF-ß1 bioavailability, Smad2/3 phosphorylation, and α-SMA expression in the fibrous area. Accordingly, fibroblast on stiff but not soft matrix exhibited obvious MFB phenotype, as evidenced by enlarged cell, hyperproliferation, well-developed α-SMA fibers, and elevated ECM related proteins, while silencing of integrin αV almost abolished this switch via attenuating paracrine of TGF-ß1 and nuclear translocation of Smad2/3. CONCLUSION: This study illustrated that increased tissue stiffness activates CFs into MFBs by integrin αV mediated mechanoparacrine of TGF-ß1, especially in immature scar area, which ultimately promotes fibrous scar maturation.
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Infarto do Miocárdio , Miofibroblastos , Animais , Camundongos , Actinas/metabolismo , Cicatriz/metabolismo , Colágeno/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Fibrose , Integrina alfaV/metabolismo , Infarto do Miocárdio/patologia , Miofibroblastos/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismoRESUMO
Phosphate-based electrolyte propels the advanced battery system with high safety. Unfortunately, restricted by poor electrochemical stability, it is difficult to be compatible with advanced lithium metal anodes and Ni-rich cathodes. To alleviate these issues, the study has developed a phosphate-based localized high-concentration electrolyte with a nitrate-driven solvation structure, and the nitrate-derived N-rich inorganic interface shows excellent performance in stabilizing the LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode interface and modulating the lithium deposition morphology on the anode. The results show that the Li|| NCM811 cell has exceptional long-cycle stability of >80% capacity retention after 800 cycles at 4.3 V, 1 C. A more prominent capacity retention rate of 93.3% after 200 cycles can be reached with the high voltage of 4.5 V. While being compatible with the phosphate-based electrolyte with good flame retardancy and the good electrochemical stability of Ni-rich lithium metal battery (LMBs) systems, the present work expands the construction of anion-rich solvation structures, which is expected to promote the development of the high-performance LMBs with safety.
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pH-dependent peptide biomaterials hold tremendous potential for cell delivery and tissue engineering. However, identification of responsive self-assembling sequences with specified secondary structure remains a challenge. In this work, An experimental procedure based on the one-bead one-compound (OBOC) combinatorial library is developed to rapidly screen self-assembling ß-sheet peptides at neutral aqueous solution (pH 7.5) and disassemble at weak acidic condition (pH 6.5). Using the hydrophobic fluorescent molecule thioflavin T (ThT) as a probe, resin beads displaying self-assembling peptides show fluorescence under pH 7.5 due to the insertion of ThT into the hydrophobic domain, and are further cultured in pH 6.5 solution. The beads with extinguished fluorescence are selected. Three heptapeptides are identified that can self-assemble into nanofibers or nanoparticles at pH 7.5 and disassemble at pH 6.5. P1 (LVEFRHY) shows a rapid acid response and morphology transformation with pH modulation. Changes in the charges of histidine and hydrophobic phenyl motif of phenylalanine may play important roles in the formation of pH-responsive ß-sheet nanofiber. This high-throughput screening method provides an efficient way to identify pH-dependent ß-sheet self-assembling peptide and gain insights into structural design of such nanomaterials.
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Peptídeos , Concentração de Íons de Hidrogênio , Peptídeos/química , Conformação Proteica em Folha beta , Ensaios de Triagem em Larga Escala/métodos , Nanofibras/química , Interações Hidrofóbicas e Hidrofílicas , Benzotiazóis/químicaRESUMO
The slow reaction kinetics and severe shuttle effect of lithium polysulfide make Li-S battery electrochemical performance difficult to meet the demands of large electronic devices such as electric vehicles. Based on this, an electrocatalyst constructed by metal phase material (MoS2) and semiconductor phase material (SnS2) with ohmic contact is designed for inhibiting the dissolution of lithium polysulfide with improving the reaction kinetics. According to the density-functional theory calculations, it is found that the heterostructured samples with ohmic contacts can effectively reduce the reaction-free energy of lithium polysulfide to accelerate the sulfur redox reaction, in addition to the excellent electron conduction to reduce the overall activation energy. The metallic sulfide can add more sulfophilic sites to promote the capture of polysulfide. Thanks to the ohmic contact design, the carbon nanotube-MoS2-SnS2 achieved a specific capacity of 1437.2 mAh g-1 at 0.1 C current density and 805.5 mAh g-1 after 500 cycles at 1 C current density and is also tested as a pouch cell, which proves to be valuable for practical applications. This work provides a new idea for designing an advanced and efficient polysulfide catalyst based on ohmic contact.
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The localized high-concentration electrolyte (LHCE) propels the advanced high-voltage battery system. Sulfone-based LHCE is a transformative direction compatible with high energy density and high safety. In this work, the application of lithium bis(trifluoromethanesulphonyl)imide and lithium bis(fluorosulfonyl)imide (LiFSI) in the LHCE system constructed from sulfolane and 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (TTE) is investigated. The addition of diluent causes an increase of contact ion pairs and ionic aggregates in the solvation cluster and an acceptable quantity of free solvent molecules. A small amount of LiFSI as an additive can synergistically decompose with TTE on the cathode and participate in the construction of both electrode interfaces. The designed electrolyte helps the Ni-rich system to cycle firmly at a high voltage of 4.5 V. Even with high mass load and lean electrolyte, it can keep a reversible specific capacity of 91.5% after 50 cycles. The constructed sulfone-based electrolyte system exhibits excellent thermal stability far beyond the commercial electrolytes. Further exploration of in-situ gelation has led to a quick conversion of the designed liquid electrolyte to the gel state, accompanied by preserved stability, which provides a direction for the synergistic development of LHCE with gel electrolytes.
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Abdominal aortic aneurysm (AAA) represents a critical cardiovascular condition characterized by localized dilation of the abdominal aorta, carrying a significant risk of rupture and mortality. Current treatment options are limited, necessitating novel therapeutic approaches. This study investigates the potential of a pioneering nanodrug delivery system, RAP@PFB, in mitigating AAA progression. RAP@PFB integrates pentagalloyl glucose (PGG) and rapamycin (RAP) within a metal-organic-framework (MOF) structure through a facile assembly process, ensuring remarkable drug loading capacity and colloidal stability. The synergistic effects of PGG, a polyphenolic antioxidant, and RAP, an mTOR inhibitor, collectively regulate key players in AAA pathogenesis, such as macrophages and smooth muscle cells (SMCs). In macrophages, RAP@PFB efficiently scavenges various free radicals, suppresses inflammation, and promotes M1-to-M2 phenotype repolarization. In SMCs, it inhibits apoptosis and calcification, thereby stabilizing the extracellular matrix and reducing the risk of AAA rupture. Administered intravenously, RAP@PFB exhibits effective accumulation at the AAA site, demonstrating robust efficacy in reducing AAA progression through multiple mechanisms. Moreover, RAP@PFB demonstrates favorable biosafety profiles, supporting its potential translation into clinical applications for AAA therapy.
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Emerging evidence suggests that circular RNA (circRNA) is an important regulator of a variety of pathological processes and serves as a promising biomarker for many complex human diseases. Nevertheless, there are relatively few known circRNA-disease associations, and uncovering new circRNA-disease associations by wet-lab methods is time consuming and costly. Considering the limitations of existing computational methods, we propose a novel approach named MNMDCDA, which combines high-order graph convolutional networks (high-order GCNs) and deep neural networks to infer associations between circRNAs and diseases. Firstly, we computed different biological attribute information of circRNA and disease separately and used them to construct multiple multi-source similarity networks. Then, we used the high-order GCN algorithm to learn feature embedding representations with high-order mixed neighborhood information of circRNA and disease from the constructed multi-source similarity networks, respectively. Finally, the deep neural network classifier was implemented to predict associations of circRNAs with diseases. The MNMDCDA model obtained AUC scores of 95.16%, 94.53%, 89.80% and 91.83% on four benchmark datasets, i.e., CircR2Disease, CircAtlas v2.0, Circ2Disease and CircRNADisease, respectively, using the 5-fold cross-validation approach. Furthermore, 25 of the top 30 circRNA-disease pairs with the best scores of MNMDCDA in the case study were validated by recent literature. Numerous experimental results indicate that MNMDCDA can be used as an effective computational tool to predict circRNA-disease associations and can provide the most promising candidates for biological experiments.
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Redes Neurais de Computação , RNA Circular , Humanos , AlgoritmosRESUMO
Fungal infections caused by Candida species pose a serious threat to humankind. Antibiotics abuse and the ability of Candida species to form biofilm have escalated the emergence of drug resistance in clinical settings and hence, rendered it more difficult to treat Candida-related diseases. Lethal effects of Candida infection are often due to inefficacy of antimicrobial treatments and failure of host immune response to clear infections. Previous studies have shown that a combination of riboflavin with UVA (riboflavin/UVA) light demonstrate candidacidal activity albeit its mechanism of actions remain elusive. Thus, this study sought to investigate antifungal and antibiofilm properties by combining riboflavin with UVA against Candida albicans and non-albicans Candida species. The MIC20 for the fluconazole and riboflavin/UVA against the Candida species tested was within the range of 0.125-2 µg/mL while the SMIC50 was 32 µg/mL. Present findings indicate that the inhibitory activities exerted by riboflavin/UVA towards planktonic cells are slightly less effective as compared to controls. However, the efficacy of the combination towards Candida species biofilms showed otherwise. Inhibitory effects exerted by riboflavin/UVA towards most of the tested Candida species biofilms points towards a variation in mode of action that could make it an ideal alternative therapeutic for biofilm-related infections.
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Antifúngicos , Biofilmes , Candida albicans , Candida , Testes de Sensibilidade Microbiana , Riboflavina , Raios Ultravioleta , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Biofilmes/efeitos da radiação , Riboflavina/farmacologia , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Plâncton/efeitos dos fármacos , Fluconazol/farmacologia , HumanosRESUMO
Insect chitinases have been proposed as potential targets for pest control. In this work, a novel group IV chitinase gene, MdCht9, from Musca domestica was found to have multiple functions in the physiological activity, including chitin regulation, development and antifungal immunity. The MdCht9 gene was cloned and sequenced, its phylogeny was analysed and its expression was determined in normal and 20E treated larvae. Subsequently, RNA interference (RNAi)-mediated MdCht9 knockdown was performed, followed by biochemical assays, morphological observations and transcriptome analysis. Finally, the recombinant protein MdCht9 (rMdCht9) was purified and tested for anti-microbial activity and enzyme characteristics. The results showed that MdCht9 consists of three domains, highly expressed in a larval salivary gland. RNAi silencing of MdCht9 resulted in significant down-regulation of chitin content and expression of 15 chitin-binding protein (CBP) genes, implying a new insight that MdCht9 might regulate chitin content by influencing the expression of CBPs. In addition, more than half of the lethality and partial wing deformity appeared due to the dsMdCht9 treatment. In addition, the rMdCht9 exhibited anti-microbial activity towards Candida albicans (fungus) but not towards Escherichia coli (G-) or Staphylococcus aureus (G+). Our work expands on previous studies of chitinase while providing a potential target for pest management.
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Quitinases , Moscas Domésticas , Animais , Moscas Domésticas/genética , Moscas Domésticas/metabolismo , Quitinases/metabolismo , Larva , Proteínas Recombinantes/genética , Quitina/metabolismoRESUMO
BACKGROUND: The alveolar epithelial type II cell (AT2) and its senescence play a pivotal role in alveolar damage and pulmonary fibrosis. Cell circadian rhythm is strongly associated with cell senescence. Differentiated embryonic chondrocyte expressed gene 1 (DEC1) is a very important circadian clock gene. However, the role of DEC1 in AT2 senescence and pulmonary fibrosis was still unclear. RESULTS: In this study, a circadian disruption model of light intervention was used. It was found that circadian disruption exacerbated pulmonary fibrosis in mice. To understand the underlying mechanism, DEC1 levels were investigated. Results showed that DEC1 levels increased in lung tissues of IPF patients and in bleomycin-induced mouse fibrotic lungs. In vitro study revealed that bleomycin and TGF-ß1 increased the expressions of DEC1, collagen-I, and fibronectin in AT2 cells. Inhibition of DEC1 mitigated bleomycin-induced fibrotic changes in vitro and in vivo. After that, cell senescence was observed in bleomycin-treated AT2 cells and mouse models, but these were prevented by DEC1 inhibition. At last, p21 was confirmed having circadian rhythm followed DEC1 in normal conditions. But bleomycin disrupted the circadian rhythm and increased DEC1 which promoted p21 expression, increased p21 mediated AT2 senescence and pulmonary fibrosis. CONCLUSIONS: Taken together, circadian clock protein DEC1 mediated pulmonary fibrosis via p21 and cell senescence in alveolar epithelial type II cells.