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DNA N6-methyladenine (6mA) modification is the most prevalent DNA modification in prokaryotes, but whether it exists in human cells and whether it plays a role in human diseases remain enigmatic. Here, we showed that 6mA is extensively present in the human genome, and we cataloged 881,240 6mA sites accounting for â¼0.051% of the total adenines. [G/C]AGG[C/T] was the most significantly associated motif with 6mA modification. 6mA sites were enriched in the coding regions and mark actively transcribed genes in human cells. DNA 6mA and N6-demethyladenine modification in the human genome were mediated by methyltransferase N6AMT1 and demethylase ALKBH1, respectively. The abundance of 6mA was significantly lower in cancers, accompanied by decreased N6AMT1 and increased ALKBH1 levels, and downregulation of 6mA modification levels promoted tumorigenesis. Collectively, our results demonstrate that DNA 6mA modification is extensively present in human cells and the decrease of genomic DNA 6mA promotes human tumorigenesis.
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Adenina/análogos & derivados , Homólogo AlkB 1 da Histona H2a Dioxigenase/metabolismo , Genoma Humano , DNA Metiltransferases Sítio Específica (Adenina-Específica)/metabolismo , Adenina/metabolismo , Homólogo AlkB 1 da Histona H2a Dioxigenase/genética , Animais , Carcinogênese/genética , DNA/genética , Metilação de DNA , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , DNA Metiltransferases Sítio Específica (Adenina-Específica)/genéticaRESUMO
γδ T cells are becoming increasingly popular because of their attractive potential for antitumor immunotherapy. However, the role and assessment of γδ T cells in head and neck squamous cell carcinoma (HNSCC) are not well understood. We aimed to explore the prognostic value of γδ T cell and predict its abundance using a radiomics model. Computer tomography images with corresponding gene expression data and clinicopathological data were obtained from online databases. After outlining the volumes of interest manually, the radiomic features were screened using maximum melevance minimum redundancy and recursive feature elimination algorithms. A radiomics model was developed to predict γδ T-cell abundance using gradient boosting machine. Kaplan-Meier survival curves and univariate and multivariate Cox regression analyses were used for the survival analysis. In this study, we confirmed that γδ T-cell abundance was an independent predictor of favorable overall survival (OS) in patients with HNSCC. Moreover, a radiomics model was built to predict the γδ T-cell abundance level (the areas under the operating characteristic curves of 0.847 and 0.798 in the training and validation sets, respectively). The calibration and decision curves analysis demonstrated the fitness of the model. The high radiomic score was an independent protective factor for OS. Our results indicated that γδ T-cell abundance was a promising prognostic predictor in HNSCC, and the radiomics model could discriminate its abundance levels and predict OS. The noninvasive radiomics model provided a potentially powerful prediction tool to aid clinical judgment and antitumor immunotherapy.
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Neoplasias de Cabeça e Pescoço , Radiômica , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Algoritmos , Calibragem , Neoplasias de Cabeça e Pescoço/diagnóstico por imagemRESUMO
We evaluated the validity and reproducibility of a semiquantitative food frequency questionnaire (FFQ) for measuring intakes of 149 foods and 25 food groups among 736 participants of the Women's Lifestyle Validation Study (WLVS, 2010-2012) and 649 participants of the Men's Lifestyle Validation Study (MLVS, 2011-2013). Validity of the FFQ compared with two 7-day dietary records measured 6 months apart and the reproducibility between 2 FFQs administered 1 year apart (FFQ1 and FFQ2) were assessed using Spearman correlations and intraclass correlation coefficients. The average 1-year reproducibility of FFQ-measured foods was 0.64 in both the WLVS and MLVS. Reproducibility of the food groups (mean = 0.71 among women and 0.72 among men) was generally higher than that for individual foods. Among women, the average validity correlation for individual foods was 0.59 when comparing FFQ2 with the 7-day dietary records. Among men, the corresponding average validity correlation was 0.61. Compared with individual foods, food groups had slightly higher validity correlations in both women (range, 0.45-0.92; mean = 0.61) and men (range, 0.46-0.88; mean = 0.65). This study reaffirms that the FFQ performs well in measuring most foods and food groups and provides data to adjust for measurement errors in epidemiologic studies of foods and food groups.
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Alimentos , Estilo de Vida , Masculino , Humanos , Feminino , Reprodutibilidade dos Testes , Inquéritos e Questionários , Registros de Dieta , Dieta , Inquéritos sobre DietasRESUMO
BACKGROUND: There is a lack of effective therapeutic strategies for amyotrophic lateral sclerosis (ALS); therefore, drug repurposing might provide a rapid approach to meet the urgent need for treatment. METHODS: To identify therapeutic targets associated with ALS, we conducted Mendelian randomization (MR) analysis and colocalization analysis using cis-eQTL of druggable gene and ALS GWAS data collections to determine annotated druggable gene targets that exhibited significant associations with ALS. By subsequent repurposing drug discovery coupled with inclusion criteria selection, we identified several drug candidates corresponding to their druggable gene targets that have been genetically validated. The pharmacological assays were then conducted to further assess the efficacy of genetics-supported repurposed drugs for potential ALS therapy in various cellular models. RESULTS: Through MR analysis, we identified potential ALS druggable genes in the blood, including TBK1 [OR 1.30, 95%CI (1.19, 1.42)], TNFSF12 [OR 1.36, 95%CI (1.19, 1.56)], GPX3 [OR 1.28, 95%CI (1.15, 1.43)], TNFSF13 [OR 0.45, 95%CI (0.32, 0.64)], and CD68 [OR 0.38, 95%CI (0.24, 0.58)]. Additionally, we identified potential ALS druggable genes in the brain, including RESP18 [OR 1.11, 95%CI (1.07, 1.16)], GPX3 [OR 0.57, 95%CI (0.48, 0.68)], GDF9 [OR 0.77, 95%CI (0.67, 0.88)], and PTPRN [OR 0.17, 95%CI (0.08, 0.34)]. Among them, TBK1, TNFSF12, RESP18, and GPX3 were confirmed in further colocalization analysis. We identified five drugs with repurposing opportunities targeting TBK1, TNFSF12, and GPX3, namely fostamatinib (R788), amlexanox (AMX), BIIB-023, RG-7212, and glutathione as potential repurposing drugs. R788 and AMX were prioritized due to their genetic supports, safety profiles, and cost-effectiveness evaluation. Further pharmacological analysis revealed that R788 and AMX mitigated neuroinflammation in ALS cell models characterized by overly active cGAS/STING signaling that was induced by MSA-2 or ALS-related toxic proteins (TDP-43 and SOD1), through the inhibition of TBK1 phosphorylation. CONCLUSIONS: Our MR analyses provided genetic evidence supporting TBK1, TNFSF12, RESP18, and GPX3 as druggable genes for ALS treatment. Among the drug candidates targeting the above genes with repurposing opportunities, FDA-approved drug-R788 and AMX served as effective TBK1 inhibitors. The subsequent pharmacological studies validated the potential of R788 and AMX for treating specific ALS subtypes through the inhibition of TBK1 phosphorylation.
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Aminopiridinas , Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/genética , Reposicionamento de Medicamentos , Análise da Randomização Mendeliana , Proteínas Serina-Treonina Quinases/genéticaRESUMO
BACKGROUND: Gasdermin D (GSDMD)-mediated pyroptotic cell death is implicated in the pathogenesis of cognitive deficits in sepsis-associated encephalopathy (SAE), yet the underlying mechanisms remain largely unclear. Dynamin-related protein 1 (Drp1) facilitates mitochondrial fission and ensures quality control to maintain cellular homeostasis during infection. This study aimed to investigate the potential role of the GSDMD/Drp1 signaling pathway in cognitive impairments in a mouse model of SAE. METHODS: C57BL/6 male mice were subjected to cecal ligation and puncture (CLP) to establish an animal model of SAE. In the interventional study, mice were treated with the GSDMD inhibitor necrosulfonamide (NSA) or the Drp1 inhibitor mitochondrial division inhibitor-1 (Mdivi-1). Surviving mice underwent behavioral tests, and hippocampal tissues were harvested for histological analysis and biochemical assays at corresponding time points. Haematoxylin-eosin staining and TUNEL assays were used to evaluate neuronal damage. Golgi staining was used to detect synaptic dendritic spine density. Additionally, transmission electron microscopy was performed to assess mitochondrial and synaptic morphology in the hippocampus. Local field potential recordings were conducted to detect network oscillations in the hippocampus. RESULTS: CLP induced the activation of GSDMD, an upregulation of Drp1, leading to associated mitochondrial impairment, neuroinflammation, as well as neuronal and synaptic damage. Consequently, these effects resulted in a reduction in neural oscillations in the hippocampus and significant learning and memory deficits in the mice. Notably, treatment with NSA or Mdivi-1 effectively prevented these GSDMD-mediated abnormalities. CONCLUSIONS: Our data indicate that the GSDMD/Drp1 signaling pathway is involved in cognitive deficits in a mouse model of SAE. Inhibiting GSDMD or Drp1 emerges as a potential therapeutic strategy to alleviate the observed synaptic damages and network oscillations abnormalities in the hippocampus of SAE mice.
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Disfunção Cognitiva , Encefalopatia Associada a Sepse , Sepse , Animais , Masculino , Camundongos , Disfunção Cognitiva/metabolismo , Dinaminas/metabolismo , Hipocampo/metabolismo , Camundongos Endogâmicos C57BL , Sepse/patologia , Encefalopatia Associada a Sepse/metabolismo , Transdução de SinaisRESUMO
ConspectusWell-controlled olefin insertion is critical for achieving catalytic and productive bulk and fine-chemical synthesis. Developing efficient and selective methods for meeting diverse insertion demands is extremely noteworthy, as it supports numerous transformations. The challenges are related to improving catalyst performance and selectivity control and uniting previously unreactive substrate pairs to achieve higher molecular structural complexity and utility. Nickel catalysts have received persistent attention in higher substituted olefin synthesis and polymerization, and numerous new strategies have been established to fulfill the ever-changing demands. This Account focuses on the recent progress based on N-heterocyclic carbene (NHC) ligands and nickel catalysts in our laboratory in using simple terminal olefins as olefin donors or acceptors.It begins with a brief history of olefin codimerization and the major advances in hydrovinylation achieved by other research groups using ethylene as an olefin donor. It then describes problems related to the reductive elimination that can occur when both the hydrometalated alkene and NHC are on the catalyst. It emphasizes the impact of NHC catalyst generation methods on the competing reactivity. Next, it explains the principal challenges and great opportunities in using our method (with α-olefins as olefin donors and alkenyl sources) to replace intermolecular reductive hydroalkenylation reactions (which require rare and more expensive alkenyl halides and boronic acids as reactants, alongside a stoichiometric amount of metallic reagents). The Account then illustrates the potential uses of our method for solving challenging organic synthesis problems using tailor-made (NHC)Ni(II) catalysts to allow redox-neutral catalytic cycles based on high chemo- and regioselective cross-insertion controls. It shows that upon optimal steric and electronic cooperation between the NHC, olefin donor, and olefin acceptor, regiodivergent insertion and convergent synthesis can be achieved easily.In the course of our work, we uncovered several unique insights into regulating (anti-)Markovnikov hydronickelation, carbonickelation, hydrocarbonation, ring closure, 1,3-allyl shift, isomerization, and catalyst regeneration under green, neutral, and mild-temperature conditions. These insights are also outlined here, along with theoretical calculations that offer additional understandings of the insertion reactivity and selectivity differences observed between the NHC and the highly related phosphorus-based Ni(II) hydride-catalyzed cross-hydroalkenylation and cycloisomerization systems.Compared to traditional olefin and cyclic structure synthesis technology, such as olefin cross-metathesis, enyne cyclization, and cross-coupling reactions, the new catalyst systems often offer previously inaccessible product structural characteristics, substrate scope, and outcomes. In particular, the method is effective for the catalytic synthesis of unsymmetrical and functionalized 1,1-disubstituted olefins (a.k.a. gem-olefins), 1,4-dienes (a.k.a. skipped dienes), conjugated dienes, endo- and exocyclic olefins, fused and spiro rings, and aromatic products. These syntheses are variously achieved by cross-hydroalkenylation, insertion-induced rearrangement, cycloadditions, and other approaches inspired by our investigations and detailed in this Account. Cross-hydroalkenylation can be achieved with high enantioselectivity by application of carefully designed and structurally flexible C1 and C2 chiral NHC ligands, yielding a pool of chiral branched alkenes and 1,4-dienes directly from simple chemical feedstocks used in industry. This Account will draw further attention to green alkenylation and the related development of redox-neutral catalytic cycles.
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BACKGROUND: The incidence of multiple myeloma (MM), a type of blood cancer affecting monoclonal plasma cells, is rising. Although new drugs and therapies have improved patient outcomes, MM remains incurable. Recent studies have highlighted the crucial role of the chemokine network in MM's pathological mechanism. Gaining a better understanding of this network and creating an overview of chemokines in MM could aid in identifying potential biomarkers and developing new therapeutic strategies and targets. PURPOSE: To summarize the complicated role of chemokines in MM, discuss their potential as biomarkers, and introduce several treatments based on chemokines. METHODS: Pubmed, Web of Science, ICTRP, and Clinical Trials were searched for articles and research related to chemokines. Publications published within the last 5 years are selected. RESULTS: Malignant cells can utilize chemokines, including CCL2, CCL3, CCL5, CXCL7, CXCL8, CXCL12, and CXCL13 to evade apoptosis triggered by immune cells or medication, escape from bone marrow and escalate bone lesions. Other chemokines, including CXCL4, CCL19, and CXCL10, may aid in recruiting immune cells, increasing their cytotoxicity against cancer cells, and inducing apoptosis of malignant cells. CONCLUSION: Utilizing anti-tumor chemokines or blocking pro-tumor chemokines may provide new therapeutic strategies for managing MM. Inspired by developed CXCR4 antagonists, including plerixafor, ulocuplumab, and motixafortide, more small molecular antagonists or antibodies for pro-tumor chemokine ligands and their receptors can be developed and used in clinical practice. Along with inhibiting pro-tumor chemokines, studies suggest combining chemokines with chimeric antigen receptor (CAR)-T therapy is promising and efficient.
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Compostos Heterocíclicos , Mieloma Múltiplo , Humanos , Mobilização de Células-Tronco Hematopoéticas , Quimiocinas , Transdução de Sinais , BiomarcadoresRESUMO
Species of Baylisascaris (Nematoda: Ascarididae) are of great veterinary and zoonotic significance, owing to cause Baylisascariosis or Baylisascariasis in wildlife, captive animals and humans. However, the phylogenetic relationships of the current 10 Baylisascaris species remain unclear. Moreover, our current knowledge of the detailed morphology and morphometrics of the important zoonotic species B. procyonis is still insufficient. The taxonomical status of B. procyonis and B. columnaris remains under debate. In the present study, the detailed morphology of B. procyonis was studied using light and scanning electron microscopy based on newly collected specimens from the raccoon Procyon lotor (Linnaeus) in China. The results of the ASAP analysis and Bayesian inference (BI) using the 28S, ITS, cox1 and cox2 genetic markers did not support that B. procyonis and B. columnaris represent two distinct species. Integrative morphological and molecular assessment challenged the validity of B. procyonis, and suggested that B. procyonis seems to represent a synonym of B. columnaris. Molecular phylogenetic results indicated that the species of Baylisascaris were grouped into 4 clades according to their host specificity. The present study provided new insights into the taxonomic status of B. procyonis and preliminarily clarified the phylogenetic relationships of Baylisascaris species.
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Ascaridídios , Ascaridoidea , Parasitos , Animais , Humanos , Filogenia , Teorema de Bayes , Ascaridoidea/genética , GuaxininsRESUMO
Prussian blue analogues have shown promise as cathode materials competing with sodium ion batteries, while the presence of water molecules severely affects their performance in batteries. Based on density functional theory, the effect of water molecules on the diffusion of alkali ions is revealed by employing CuHCF (copper hexacyanoferrate) as a cathode. The diffusions of alkali ions in CuHCF with or without inserted water molecules are investigated. It was found that Li+/Na+ forms hydrated ions with water molecules in the interstitial voids, while K+ cannot form hydrated ions due to spatial constraints. It would lead to a dramatic increase of diffusion barriers when Li+/Na+ ions carrying water molecules diffuse. The number of inserted water molecules significantly impacts the diffusion of Li+/Na+ ions.
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Aqueous ion batteries have great commercial potential in green power and energy storage due to their green nature, safety and high ionic conductivities. Different from organic electrolytes, alkali ions (Li+, Na+, and K+) inevitably bring water molecules into the electrodes during the charging/discharging process due to the hydration of ions with water molecules. The selectivity of alkali ions and the mechanism of how water molecules are involved in the ion extraction/insertion process in the electrodes have not been clarified. In this study, we focus on the characteristics of the intra-layer distribution of different hydrated ions (Li+, Na+, and K+) and the quantitative analysis of the selectivity of hydrated cations in aqueous batteries. We found that the concentration of hydrated ions greatly affects their distribution within the 1T-MoS2 layers, and the presence of hydrogen bonding and O-O repulsive forces between water molecules causes the hydrated ions to gradually form chains from the dispersed state under the effect of hydrogen bonding and ionic bonding, then further form strips, and ultimately be densely dispersed within the whole layer. In addition, the chemical potential difference of hydrated ions is the key to the competitive reaction, and we quantitatively analyze the selectivity relationship between hydrated cations throughout the charging and discharging process; hydrated sodium ions will have better performance than lithium and potassium ions in aqueous batteries.
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FAK (focal adhesion kinase) is widely involved in cancer growth and drug resistance development. Thus, FAK inhibition has emerged as an effective strategy for tumor treatment both as a monotherapy or in combination with other treatments. But the current FAK inhibitors mainly concentrate on its kinase activity, overlooking the potential significance of FAK scaffold proteins. In this study we employed the PROTAC technology, and designed a novel PROTAC molecule F2 targeting FAK based on the FAK inhibitor IN10018. F2 exhibited potent inhibitory activities against 4T1, MDA-MB-231, MDA-MB-468 and MDA-MB-435 cells with IC50 values of 0.73, 1.09, 5.84 and 3.05 µM, respectively. On the other hand, F2 also remarkably reversed the multidrug resistance (MDR) in HCT8/T, A549/T and MCF-7/ADR cells. Both the effects of F2 were stronger than the FAK inhibitor IN10018. To our knowledge, F2 was the first reported FAK-targeted PROTAC molecule exhibiting reversing effects on chemotherapeutic drug resistance, and its highest reversal fold could reach 158 times. The anti-tumor and MDR-reversing effects of F2 might be based on its inhibition on AKT (protein kinase B, PKB) and ERK (extracellular signal-regulated kinase) signaling pathways, as well as its impact on EMT (epithelial-mesenchymal transition). Furthermore, we found that F2 could reduce the protein level of P-gp in HCT8/T cells, thereby contributing to reverse drug resistance from another perspective. Our results will boost confidence in future research focusing on targeting FAK and encourage further investigation of PROTAC with potent in vivo effects.
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OBJECTIVE: To study how Pneumoperitoneum under Trendelenburg position for robot-assisted laparoscopic surgery impact the perioperative respiratory parameters, diagrammatic function, etc. METHODS: Patients undergoing robot-assisted laparoscopic surgery in the Trendelenburg position and patients undergoing general surgery in the supine position were selected. The subjects were divided into two groups according to the type of surgery: robot-assisted surgery group and general surgery group. â Respiratory parameters such as lung compliance, oxygenation index, and airway pressure were recorded at 5 min after intubation, 1 and 2 h after pneumoperitoneum. â¡ Diaphragm excursion (DE) and diaphragm thickening fraction (DTF) were recorded before entering the operating room (T1), immediately after extubation (T2), 10 min after extubation (T3), and upon leaving the postanesthesia care unit (T4). ⢠Peripheral venous blood (5 ml) was collected before surgery and 30 min after extubation and was analyzed by enzyme-linked immunosorbent assay to determine the serum concentration of Clara cell secretory protein 16 (CC16) and surfactant protein D (SP-D). RESULT: â Compared with the general surgery group (N = 42), the robot-assisted surgery group (N = 46) presented a significantly higher airway pressure and lower lung compliance during the surgery(P < 0.001). â¡ In the robot-assisted surgery group, the DE significantly decreased after surgery (P < 0.001), which persisted until patients were discharged from the PACU (P < 0.001), whereas the DTF only showed a transient decrease postoperatively (P < 0.001) and returned to its preoperative levels at discharge (P = 0.115). In the general surgery group, the DE showed a transient decrease after surgery(P = 0.011) which recovered to the preoperative levels at discharge (P = 1). No significant difference in the DTF was observed among T1, T2, T3, and T4. ⢠Both the general and robot-assisted surgery reduced the postoperative serum levels of SP-D (P < 0.05), while the robot-assisted surgery increased the postoperative levels of CC16 (P < 0.001). CONCLUSION: Robot-assisted laparoscopic surgery significantly impairs postoperative diaphragm function, which does not recover to preoperative levels at PACU discharge. Elevated levels of serum CC16 after surgery suggest potential lung injury. The adverse effects may be attributed to the prolonged Trendelenburg position and pneumoperitoneum during laparoscopic surgery.
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Laparoscopia , Pneumoperitônio , Procedimentos Cirúrgicos Robóticos , Robótica , Humanos , Diafragma , Decúbito Inclinado com Rebaixamento da Cabeça , Proteína D Associada a Surfactante Pulmonar , RespiraçãoRESUMO
Abbreviata baltazardi Chabaud, 1953 (Nematoda: Physalopteridae) is a hitherto poorly known parasitic nematode species reported from Phrynocephalus helioscopus Pallas (Squamata: Agamidae) in Iran. The current knowledge on the morphology of A. baltazardi is still very limited. In the present study, the detailed morphology of A. baltazardi was studied using light microscopy and, for the first time, scanning electron microscopy, based on newly collected specimens from the yarkand toad-headed agama P. axillaris Blanford Pallas (Squamata: Agamidae) in China. Some erroneous or previously unreported morphological features of A. baltazardi were observed using SEM, which include the presence of one large semicircular protrusion and 20-30 denticles on each pseudolabium, the absence of precloacal medioventral papilla in some individuals and the presence of 4-5 postcloacal medioventral papillae in males. SEM observations also clearly showed the detailed morphology of deirids, cloacal ornamentation, caudal papillae, vulva and egg. Abbreviata baltazardi represents the first species of Abbreviata Travassos, 1920 reported in China.
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Microscopia Eletrônica de Varredura , Especificidade da Espécie , Animais , Espirurídios/classificação , Espirurídios/anatomia & histologia , Espirurídios/ultraestrutura , Feminino , Masculino , Lagartos/parasitologia , ChinaRESUMO
The development of porous materials with flexible-robust characteristics shows some unique advantages to target high performance for gas separation, but remains a daunting challenge to achieve so far. Herein, we report a carboxyl-based hydrogen-bonded organic framework (ZJU-HOF-8a) with flexible-robust porosity for efficient purification of natural gas. ZJU-HOF-8a features a four-fold interpenetrated structure with dia topology, wherein abundant supramolecular entanglements are formed between the adjacent subnetworks through weak intermolecular hydrogen bonds. This structural configuration could not only stabilize the whole framework to establish the permanent porosity, but also enable the framework to show some flexibility due to its weak intermolecular interactions (so-called flexible-robust framework). The flexible-robust porosity of ZJU-HOF-8a was exclusively confirmed by gas sorption isotherms and single-crystal X-ray diffraction studies, showing that the flexible pore pockets can be opened by C3H8 and n-C4H10 molecules rather by C2H6 and CH4. This leads to notably higher C3H8 and n-C4H10 uptakes with enhanced selectivities than C2H6 over CH4 under ambient conditions, affording one of the highest n-C4H10/CH4 selectivities. The gas-loaded single-crystal structures coupled with theoretical simulations reveal that the loading of n-C4H10 can induce an obvious framework expansion along with pore pocket opening to improve n-C4H10 uptake and selectivity, while not for C2H6 adsorption. This work suggests an effective strategy of designing flexible-robust HOFs for improving gas separation properties.
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BACKGROUND: Targeted drugs are not quite effective for prolonging the survival of patients with gastric cancer due to off-target effects as well as tumor immune escape mechanisms. Circular RNAs widely exist in tumor regions as biomarkers and can be developed as effective drug targets. METHODS: Western blot, QRT-PCR, fluorescence in situ hybridization, and flow cytometry were used to investigate the function of hsa_circ_0136666 in promoting the proliferation of gastric cancer cells. Tissue immunofluorescence, enzyme-linked immunosorbent assay (ELISA), as well as flow cytometric analysis, was conducted to explore the process of tumor immune evasion in tumor-bearing mice. The differences of circRNA expression in clinical samples were analyzed through tissue microarray FISH. The effect of siRNA on improving the efficacy of anti-PDL1 drugs and suppressing the immune microenvironment was evaluated by the coadministration model. RESULTS: We demonstrated that hsa_circ_0136666 was widely and highly expressed in gastric cancer tissues and cells. Functionally, hsa_circ_0136666 promoted gastric cancer tumor proliferation and tumor microenvironment formation, leading to tumorigenesis immune escape, and this effect was dependent on CD8 + T cells. Mechanistically, we confirmed that hsa_circ_0136666 competitively upregulated PRKDC expression by sponging miR-375-3p, regulating immune checkpoint proteins, prompting phosphorylation of PD-L1 to preventing its degradation, driving PD-L1 aggregation and suppressing immune function, thereby impairing cancer immune responses. In terms of application, we found that LNP-siRNA effectively improved anti-PDL1 drug efficacy and inhibited immune escape. CONCLUSION: Our results reveal an oncogenic role played by hsa_circ_0136666 in gastric cancer, driving PD-L1 phosphorylation via the miR-375/PRKDC signaling axis, prompting immune escape. This work proposes a completely new pathogenic mechanism of gastric cancer, uncovers a novel role for hsa_circ_0136666 as an immune target, and provides a rationale for enhancing the efficacy of anti-PD-L1 therapy for gastric cancer.
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MicroRNAs , Neoplasias Gástricas , Humanos , Animais , Camundongos , Neoplasias Gástricas/genética , Evasão Tumoral/genética , Fosforilação , Antígeno B7-H1/genética , Hibridização in Situ Fluorescente , MicroRNAs/genética , RNA Interferente Pequeno , Proliferação de Células , Linhagem Celular Tumoral , Microambiente Tumoral , Proteína Quinase Ativada por DNARESUMO
BACKGROUND: Alzheimer's disease (AD) is the leading cause of dementia. Currently, there are no effective disease-modifying treatments for AD. Mendelian randomisation (MR) has been widely used to repurpose licensed drugs and discover novel therapeutic targets. Thus, we aimed to identify novel therapeutic targets for AD and analyse their pathophysiological mechanisms and potential side effects. METHODS: A two-sample MR integrating the identified druggable genes was performed to estimate the causal effects of blood and brain druggable expression quantitative trait loci (eQTLs) on AD. A repeat study was conducted using different blood and brain eQTL data sources to validate the identified genes. Using AD markers with available genome-wide association studies data, we evaluated the causal relationship between established AD markers to explore possible mechanisms. Finally, the potential side effects of the druggable genes for AD treatment were assessed using a phenome-wide MR. RESULTS: Overall, 5883 unique druggable genes were aggregated; 33 unique potential druggable genes for AD were identified in at least one dataset (brain or blood), and 5 were validated in a different dataset. Among them, three prior druggable genes (epoxide hydrolase 2 (EPHX2), SERPINB1 and SIGLEC11) reached significant levels in both blood and brain tissues. EPHX2 may mediate the pathogenesis of AD by affecting the entire hippocampal volume. Further phenome-wide MR analysis revealed no potential side effects of treatments targeting EPHX2, SERPINB1 or SIGLEC11. CONCLUSIONS: This study provides genetic evidence supporting the potential therapeutic benefits of targeting the three druggable genes for AD treatment, which will be useful for prioritising AD drug development.
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Doença de Alzheimer , Serpinas , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Estudo de Associação Genômica Ampla , Encéfalo , Hipocampo , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
It has been demonstrated that diabetes cause neurite degeneration in the brain and cognitive impairment and neurovascular interactions are crucial for maintaining brain function. However, the role of vascular endothelial cells in neurite outgrowth and synaptic formation in diabetic brain is still unclear. Therefore, present study investigated effects of brain microvascular endothelial cells (BMECs) on high glucose (HG)-induced neuritic dystrophy using a coculture model of BMECs with neurons. Multiple immunofluorescence labelling and western blot analysis were used to detect neurite outgrowth and synapsis formation, and living cell imaging was used to detect uptake function of neuronal glucose transporters. We found cocultured with BMECs significantly reduced HG-induced inhibition of neurites outgrowth (including length and branch formation) and delayed presynaptic and postsynaptic development, as well as reduction of neuronal glucose uptake capacity, which was prevented by pre-treatment with SU1498, a vascular endothelial growth factor (VEGF) receptor antagonist. To analyse the possible mechanism, we collected BMECs cultured condition medium (B-CM) to treat the neurons under HG culture condition. The results showed that B-CM showed the same effects as BMEC on HG-treated neurons. Furthermore, we observed VEGF administration could ameliorate HG-induced neuronal morphology aberrations. Putting together, present results suggest that cerebral microvascular endothelial cells protect against hyperglycaemia-induced neuritic dystrophy and restorate neuronal glucose uptake capacity by activation of VEGF receptors and endothelial VEGF release. This result help us to understand important roles of neurovascular coupling in pathogenesis of diabetic brain, providing a new strategy to study therapy or prevention for diabetic dementia. Hyperglycaemia induced inhibition of neuronal glucose uptake and impaired to neuritic outgrowth and synaptogenesis. Cocultured with BMECs/B-CM and VEGF treatment protected HG-induced inhibition of glucose uptake and neuritic outgrowth and synaptogenesis, which was antagonized by blockade of VEGF receptors. Reduction of glucose uptake may further deteriorate impairment of neurites outgrowth and synaptogenesis.
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Células Endoteliais , Hiperglicemia , Humanos , Células Endoteliais/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Células Cultivadas , Neurônios/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo , Fatores de Crescimento do Endotélio Vascular/farmacologia , Encéfalo/metabolismo , Glucose/toxicidade , Glucose/metabolismoRESUMO
A previous study indicated that long non-coding RNA X-inactive-specific transcript (XIST) promoted ethanol-induced HSCs autophagy and activation. Considering the critical role of HSC activation in hepatic fibrosis, the aim of the present study was to reveal the exact role of XIST in liver fibrosis and its underlying mechanism. The expression of XIST in the liver from CCL4-induced mice and control mice as well as human fibrotic liver tissue and healthy liver tissue was examined. The mitochondrial reactive oxygen species (mtROS), mitochondrial membrane potential (MMP), and mitochondrial morphology were measured to assess the mitochondrial damage. The relationship between XIST and miR-539-3p as well as between miR-539-3p and ADAMTS5 was verified by a dual-luciferase reporter assay. The expression levels of HSCs activation markers were examined by Western blot. The results showed that the XIST was upregulated in fibrotic liver tissue, and overexpression of XIST induced mitochondrial dysfunction in hepatocytes. miR-539-3p directly targeted XIST, and ADAMTS5 mRNA was a downstream target of miR-539-3p. Knockdown of miR-539-3p led to an increased mitochondrial damage in hepatocytes in terms of reduced mitochondrial length, decreased MMP, and increased ROS production. However, the depletion of ADAMTS5 reversed the regulatory effect of XIST on mitochondrial damage in hepatocytes and the activation of HSCs. Our study revealed the critical role of the XIST/miR-539-3p/ADAMTS5 axis in regulating mitochondrial damage in hepatocytes and the activation of HSCs. This study may provide a potential therapeutic strategy for the treatment of liver fibrosis.
Assuntos
MicroRNAs , RNA Longo não Codificante , Humanos , Animais , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Hepatócitos/metabolismo , Cirrose Hepática/genética , Proliferação de Células/genética , Proteína ADAMTS5RESUMO
Specific medications to combat cerebellar ataxias, a group of debilitating movement disorders characterized by difficulty with walking, balance and coordination, are still lacking. Notably, cerebellar microglial activation appears to be a common feature in different types of ataxic patients and rodent models. However, direct evidence that cerebellar microglial activation in vivo is sufficient to induce ataxia is still lacking. Here, by employing chemogenetic approaches to manipulate cerebellar microglia selectively and directly, we found that specific chemogenetic activation of microglia in the cerebellar vermis directly leads to ataxia symptoms in wild-type mice and aggravated ataxic motor deficits in 3-acetylpyridine (3-AP) mice, a classic mouse model of cerebellar ataxia. Mechanistically, cerebellar microglial proinflammatory activation induced by either chemogenetic M3D(Gq) stimulation or 3-AP modeling hyperexcites Purkinje cells (PCs), which consequently triggers ataxia. Blockade of microglia-derived TNF-α, one of the most important proinflammatory cytokines, attenuates the hyperactivity of PCs driven by microglia. Moreover, chemogenetic inhibition of cerebellar microglial activation or suppression of cerebellar microglial activation by PLX3397 and minocycline reduces the production of proinflammatory cytokines, including TNF-α, to effectively restore the overactivation of PCs and alleviate motor deficits in 3-AP mice. These results suggest that cerebellar microglial activation may aggravate the neuroinflammatory response and subsequently induce dysfunction of PCs, which in turn triggers ataxic motor deficits. Our findings thus reveal a causal relationship between proinflammatory activation of cerebellar microglia and ataxic motor symptoms, which may offer novel evidence for therapeutic intervention for cerebellar ataxias by targeting microglia and microglia-derived inflammatory mediators.
Assuntos
Ataxia Cerebelar , Camundongos , Animais , Ataxia Cerebelar/induzido quimicamente , Células de Purkinje/fisiologia , Microglia , Fator de Necrose Tumoral alfa/farmacologia , Cerebelo , CitocinasRESUMO
BACKGROUND: M2-type macrophages are inflammation-suppressing cells that are differentiated after induction by cytokines such as IL-4 or IL-13, which play an important regulatory role in inflammation and influence the regression of inflammation-related diseases. All-trans retinoic acid (ATRA) has an important role in suppressing immune-mediated inflammatory responses but the effect and underlying mechanism of ATRA on the polarization of M2 macrophages remains unclear. METHODS: Macrophages were isolated from peritoneal wash fluid, and IL-4 (20 ng/mL) was used to construct a m2-type macrophage polarization model. The model was incubated with different concentrations of ATRA (15 µg/ml, 30 µg/ml, 45 µg/ml) for 24 h, and pretreated macrophages with p38MAPKα inhibitor SB202190 (20 µM). MTT, Trypan blue staining, Annexin V-PE/7-AAD staining, flow cytometry, real-time PCR and western blotting were used to investigate the effect and mechanism of ATRA on the polarization of M2 macrophages. RESULTS: Compared with the IL-4 group, the proportion of F4/80+CD206+ M2-type macrophages was significantly higher in the ATRA group (P < 0.01). mRNA and protein expression levels of Arg-1, IL-10 and TGF-ß1 were as significantly higher (P < 0.01) in the ATRA group as phosphorylation levels of STAT6 and p38MAPK (P < 0.01). After pretreatment with the addition of the inhibitor SB202190, M2-type macrophages proportion and their associated factors expression were significantly (P < 0.01) reduced, as compared with those in the ATRA group, but they were comparable (P > 0.05) with the IL-4 group. CONCLUSION: The combination of ATRA and IL-4 activated the p38MAPK/STAT6-signaling pathway to promote polarization of M2 macrophages.