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In this study, we present a ligand-free nickel(II)-catalyzed halogen exchange of aromatic halides with magnesium chloride. This method effectively facilitates the retro-Finkelstein reaction for a wide range of aryl bromides, iodides and triflates, demonstrating excellent functional group tolerance. Mechanistic studies reveal that magnesium plays a crucial role in the challenging reductive elimination from Ni(II) intermediates.
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DYRK1A, a ubiquitously expressed kinase, is linked to the dominant intellectual developmental disorder, microcephaly, and Down syndrome in humans. It regulates numerous cellular processes such as cell cycle, vesicle trafficking, and microtubule assembly. DYRK1A is a critical regulator of organ growth; however, how it regulates organ growth is not fully understood. Here, we show that the knockdown of DYRK1A in mammalian cells results in reduced cell size, which depends on mTORC1. Using proteomic approaches, we found that DYRK1A interacts with the tuberous sclerosis complex (TSC) proteins, namely TSC1 and TSC2, which negatively regulate mTORC1 activation. Furthermore, we show that DYRK1A phosphorylates TSC2 at T1462, a modification known to inhibit TSC activity and promote mTORC1 activity. We also found that the reduced cell growth upon knockdown of DYRK1A can be rescued by overexpression of RHEB, an activator of mTORC1. Our findings suggest that DYRK1A inhibits TSC complex activity through inhibitory phosphorylation on TSC2, thereby promoting mTORC1 activity. Furthermore, using the Drosophila neuromuscular junction as a model, we show that the mnb, the fly homologs of DYRK1A, is rescued by RHEB overexpression, suggesting a conserved role of DYRK1A in TORC1 regulation.
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Quinases Dyrk , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteínas Serina-Treonina Quinases , Proteínas Tirosina Quinases , Proteína 2 do Complexo Esclerose Tuberosa , Animais , Humanos , Tamanho Celular , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Técnicas de Silenciamento de Genes , Células HEK293 , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Complexos Multiproteicos/metabolismo , Complexos Multiproteicos/genética , Fosforilação , Ligação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas Tirosina Quinases/genética , Proteômica , Proteína 1 do Complexo Esclerose Tuberosa/metabolismo , Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/genética , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/genéticaRESUMO
N-Alkoxyphthalimides, one kind of phthalimide derivative, have great importance in synthesis, mainly used as free radical precursors. While the phthalimide unit, for a long time, was treated as part of the waste stream. Construction of C-N bonds has always been a hot spot, especially in reductive cross-coupling. Herein, a nickel-catalyzed reductive cross-coupling reaction of N-methoxyphthalimides with alkyl halides is described, where N-methoxyphthalimides serve as nitrogen electrophiles. This tactic provides a new approach to construct C-N bonds under mild neutral conditions. Alkyl chlorides, bromides, iodides, and sulfonates are all fit to this transformation. Moreover, the reaction could tolerate a broad substrate scope, especially base-sensitive functional groups (boron or silicon groups), as well as competitive nucleophilic groups (phenols and amides), which are incompatible with traditional Gabriel synthesis under basic conditions, demonstrating a complementary role of this work to Gabriel synthesis.
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Streptococcus gallolyticus (Sg) is a non-motile, gram-positive bacterium that causes infective endocarditis (inflammation of the heart lining). Because Sg has gained resistance to existing antibiotics and there is currently no drug available, developing effective anti-Sg drugs is critical. This study combined core proteomics with a subtractive proteomics technique to identify potential therapeutic targets for Sg. Several bioinformatics approaches were used to eliminate non-essential and human-specific homologous sequences from the bacterial proteome. Then, virulence, druggability, subcellular localization, and functional analyses were carried out to specify the participation of significant bacterial proteins in various cellular processes. The pathogen's genome contained three druggable proteins, glucosamine-1phosphate N-acetyltransferase (GlmU), RNA polymerase sigma factor (RpoD), and pantetheine-phosphate adenylyltransferase (PPAT) which could serve as effective targets for developing novel drugs. 3D structures of target protein were modeled through Swiss Model. A natural product library containing 10,000 molecules from the LOTUS database was docked against therapeutic target proteins. Following an evaluation of the docking results using the glide gscore, the top 10 compounds docked against each protein receptor were chosen. LTS001632, LTS0243441, and LTS0236112 were the compounds that exhibited the highest binding affinities against GlmU, PPAT, and RpoD, respectively, among the compounds that were chosen. To augment the docking data, molecular dynamics simulations and MM-GBSA binding free energy were also utilized. More in-vitro research is necessary to transform these possible inhibitors into therapeutic drugs, though computer validations were employed in this study. This combination of computational techniques paves the way for targeted antibiotic development, which addresses the critical need for new therapeutic strategies against S. gallolyticus infections.
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Antibacterianos , Proteínas de Bactérias , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Proteômica , Streptococcus gallolyticus , Proteômica/métodos , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/antagonistas & inibidores , Antibacterianos/farmacologia , Antibacterianos/química , Streptococcus gallolyticus/metabolismo , HumanosRESUMO
Objective: Acute myocardial infarction (AMI) is a severe cardiovascular disease that threatens human life and health globally. N6-methyladenosine (m6A) governs the fate of RNAs via m6A regulators. Nevertheless, how m6A regulators affect AMI remains to be deciphered. To solve this issue, an integrative analysis of m6A regulators in AMI was conducted. Methods: We acquired transcriptome profiles (GSE59867, GSE48060) of peripheral blood samples from AMI patients and healthy controls. Key m6A regulators were used for LASSO, and consensus clustering was conducted. Next, the m6A score was also computed. Immune cell infiltration, ferroptosis, and oxidative stress were evaluated. In-vitro and in-vivo experiments were conducted to verify the role of the m6A regulator ALKBH5 in AMI. Results: Most m6A regulators presented notable expression alterations in circulating cells of AMI patients versus those of controls. Based on key m6A regulators, we established a gene signature and a nomogram for AMI diagnosis and risk prediction. AMI patients were classified into three m6A clusters or gene clusters, respectively, and each cluster possessed the unique properties of m6A modification, immune cell infiltration, ferroptosis, and oxidative stress. Finally, the m6A score was utilized to quantify m6A modification patterns. Therapeutic targeting of ALKBH5 greatly alleviated apoptosis and intracellular ROS in H/R-induced H9C2 cells and NRCMs. Conclusion: Altogether, our findings highlight the clinical significance of m6A regulators in the diagnosis and risk prediction of AMI and indicate the critical roles of m6A modification in the regulation of immune cell infiltration, ferroptosis, and oxidative stress.
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Ferroptose , Infarto do Miocárdio , Humanos , Relevância Clínica , Infarto do Miocárdio/genética , Apoptose/genética , Análise por Conglomerados , Ferroptose/genéticaRESUMO
Diabetic nephropathy (DN) is one of the most feared complications of diabetes and key cause of end-stage renal disease (ESRD). Berberis integerrima has been widely used to treat diabetic complications, but exact molecular mechanism is yet to be discovered. Data on active ingredients of B. integerrima and target genes of both diabetic nephropathy and B.integerrima were obtained from public databases. Common results between B. integerrima and DN targets were used to create protein-protein interaction (PPI) network using STRING database and exported to Cytoscape software for the selection of hub genes based on degree of connectivity. Future, PPI network between constituents and overlapping targets was created using Cytoscape to investigate the network pharmacological effects of B. integerrima on DN. KEGG pathway analysis of core genes exposed their involvement in excess glucose-activated signaling pathway. Then, expression of core genes was validated through machine learning classifiers. Finally, PyRx and AMBER18 software was used for molecular docking and simulation. We found that Armepavine, Berberine, Glaucine, Magnoflorine, Reticuline, Quercetin inhibits the growth of diabetic nephropathy by affecting ICAM1, PRKCB, IKBKB, KDR, ALOX5, VCAM1, SYK, TBXA2R, LCK, and F3 genes. Machine learning revealed SYK and PRKCB as potential genes that could use as diagnostic biomarkers against DN. Furthermore, docking and simulation analysis showed the binding affinity and stability of the active compound with target genes. Our study revealed that B. integerrima has preventive effect on DN by acting on glucose-activated signaling pathways. However, experimental studies are needed to reveal biosafety profiles of B. integerrima in DN.Communicated by Ramaswamy H. Sarma.
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Streptococcus gallolyticus is a non-motile, gram-positive bacterium that causes infective endocarditis. S. gallolyticus has developed resistance to existing antibiotics, and no vaccine is currently available. Therefore, it is essential to develop an effective S. gallolyticus vaccine. Core proteomics was used in this study together with subtractive proteomics and reverse vaccinology approach to find antigenic proteins that could be utilized for the design of the S. gallolyticus multi-epitope vaccine. The pipeline identified two antigenic proteins as potential vaccine targets: penicillin-binding protein and the ATP synthase subunit. T and B cell epitopes from the specific proteins were forecasted employing several immunoinformatics and bioinformatics resources. A vaccine (360 amino acids) was created using a combination of seven cytotoxic T cell lymphocyte (CTL), three helper T cell lymphocyte (HTL), and five linear B cell lymphocyte (LBL) epitopes. To increase immune responses, the vaccine was paired with a cholera enterotoxin subunit B (CTB) adjuvant. The developed vaccine was highly antigenic, non-allergenic, and stable for human use. The vaccine's binding affinity and molecular interactions with the human immunological receptor TLR4 were studied using molecular mechanics/generalized Born surface area (MMGBSA), molecular docking, and molecular dynamic (MD) simulation analyses. Escherichia coli (strain K12) plasmid vector pET-28a ( +) was used to examine the ability of the vaccine to be expressed. According to the outcomes of these computer experiments, the vaccine is quite promising in terms of developing a protective immunity against diseases. However, in vitro and animal research are required to validate our findings.
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Escherichia coli K12 , Proteômica , Animais , Humanos , Simulação de Acoplamento Molecular , Epitopos de Linfócito B , Adjuvantes Imunológicos , Antibacterianos/farmacologia , Biologia Computacional , Epitopos de Linfócito T , Vacinas de Subunidades AntigênicasRESUMO
Manganese is a cheap and environmentally friendly metal on Earth. Herein, we report a manganese-promoted reductive cross-coupling using easily available and odorless disulfides as thiolating agents in an excellent 100% sulfur atom economy. The protocol featured a broad substrate scope, including various alkyl disulfides and excellent functional group compatibility, constructing diverse thioethers under simple conditions. Ultimately, thioethers can be prepared in gram-scale reactions and further transformed into structurally complex molecules.
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OBJECTIVE: To investigate the clinical features of distant metastatic penile cancer (DMPC) and the factors influencing its prognosis. METHODS: We searched the Surveillance, Epidemiology and End Results Database for cases of DMPC diagnosed between 2004 and 2019, analyzed their clinical characteristics and the cancer-specific survival (CSS) rates relating to different factors using the Kaplan-Meier method and the differences among the variables by log-rank test. We determined the variables independently associated with CSS by Cox regression analysis. RESULTS: According to the inclusion criteria, 108 cases of DMPC were identified. The patients were mainly married White people, with a median CSS of 9 months, and 1-, 2- and 3-year CSS rates of 36.4%, 17.8% and 13.5%, respectively. Pairwise comparison showed no statistically significant differences in the median overall CSS among the patients in the surgery, chemotherapy and surgery + chemotherapy groups (8 mo vs 9 mo vs 13 mo, P > 0.05). Race was an independent factor affecting the prognosis of CSS. CONCLUSION: Distant metastatic penile cancer is a rare malignancy with poor prognosis, for which there have been no existing ideal treatment options.
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Neoplasias Penianas , Masculino , Humanos , Prognóstico , Estadiamento de Neoplasias , Neoplasias Penianas/terapia , DimiristoilfosfatidilcolinaRESUMO
The RH blood group system is the most complex with over 50 antigens. So far over hundreds of RhCE variant alleles have been described resulting in weakened and/or partial expression of RhCE antigens [1], some variant Rh phenotypes are caused by exchange of genetic material between the RHD and RHCE genes, resulting in many hybrid genes, other phenotypes result from missense mutations. Variant alleles encode altered phenotypes with either weakened antigens, lacked antigens, or unexpected antigens. Besides, the mutation of RH blood group genes may lead to the changes of Rh antigen epitopes. RHCE gene mutations or polymorphisms may bring about altered RH antigens in quality and quantity [2]. Serologic weaknesses or discrepancies are regularly faced by blood transfusion laboratories, and molecular background explaining this feature can be precisely characterized only by the molecular biological methods.
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Antígenos de Grupos Sanguíneos , Antígenos E da Hepatite B , Humanos , Antígenos E da Hepatite B/genética , Alelos , Antígenos de Grupos Sanguíneos/genética , Sistema do Grupo Sanguíneo Rh-Hr/genética , Polimorfismo Genético , AntígenosRESUMO
Multifunctional electrocatalysts are crucial to cost-effective electrochemical energy conversion and storage systems requiring mutual enhancement of disparate reactions. Embedding noble metal nanoparticles in 2D metal-organic frameworks (MOFs) are proposed as an effective strategy, however, the hybrids usually suffer from poor electrochemical performance and electrical conductivity in operating conditions. Herein, ultrafine Pt nanoparticles strongly anchored on thiophenedicarboxylate acid based 2D Fe-MOF nanobelt arrays (Pt@Fe-MOF) are fabricated, allowing sufficient exposure of active sites with superior trifunctional electrocatalytic activity for hydrogen evolution, oxygen evolution, and oxygen reduction reactions. The interfacial FeâOâPt bonds can induce the charge redistribution of metal centers, leading to the optimization of adsorption energy for reaction intermediates, while the dispersibility of ultrafine Pt nanoparticles contributes to the high mass activity. When Pt@Fe-MOF is used as bifunctional catalysts for water-splitting, a low voltage of 1.65 V is required at 100 mA cm-2 with long-term stability for 20 h at temperatures (65 °C) relevant for industrial applications, outperforming commercial benchmarks. Furthermore, liquid Zn-air batteries with Pt@Fe-MOF in cathodes deliver high open-circuit voltages (1.397 V) and decent cycling stability, which motivates the fabrication of flexible quasisolid-state rechargeable Zn-air batteries with remarkable performance.
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Cardiovascular disease (CVD) is a group of diseases, affecting the human heart and accounting for 30% of deaths worldwide. Major CVDs include heart failure, hypertension, stroke, etc. Various therapeutics are available against CVD, still there is a dire need to find out potential protein drug targets to reduce economic burden and mortality rate. Goal of the current study was to utilize sequential computational techniques to find the best cardiovascular drug targets and their inhibitors. Common human cardiovascular targets of both databases (GeneCards and Uniprot) were subjected to bioinformatics analyses. Purpose was to validate putative therapeutic targets employing the structure-based bioinformatics methods to determine their physiochemical properties and biological processes. Three stable proteins, that have 0 transmembrane helices, and possess biological processes were screened as potential protein-based therapeutic targets: Hemoglobin subunit beta (HBB), Gamma-enolase (ENO2), and Cholesteryl ester transfer protein (CETP). Tertiary structures of target proteins were retrieved from PDB, and molecular docking technique was utilized to evaluate a library of 5000 phytochemicals against the interacting residues of the target protein as well as their respective standard drugs through MOE and Pyrx software. Top five phytochemicals (d-Sesamin, 1,3-benzodioxole, Sativanone, Thiamine, and Cajanol) were identified based on their RMSD and docking scores as compared to their standard drugs. The docking studies were also validated by MM-GBSA binding free energy and molecular dynamics simulations. According to the study's findings, these phytochemicals may eventually be used as drugs to treat CVD. Further in vitro testing is required to confirm their efficacy and drug potency.Communicated by Ramaswamy H. Sarma.
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Ag2O-Ag-porous silicon Bragg mirror (PSB) composite SERS substrates were successfully synthesized by using a combination of electrochemical and thermochemical methods. Test results showed that the SERS signal increased and decreased as the annealing temperature used for the substrate increased, where the most intense SERS signal was obtained using a substrate annealed at 300 °C. Stability test results showed substantial enhancement of the SERS signal intensity of the Ag2O-Ag-PSB composite one month after preparation compared with that of conventional Ag-PSB. We conclude that Ag2O nanoshells play an essential role in SERS signal enhancement. Ag2O prevents natural oxidation of Ag nanoparticles (AgNPs) and has a solid localized surface plasmon resonance (LSPR). SERS signal enhancement was tested using this substrate for serum from patients with Sjögren's syndrome (SS) and Diabetic nephropathy (DN), as well as from healthy controls (HC). SERS feature extraction was performed using principal component analysis (PCA). The extracted features were analyzed by a support vector machine (SVM) algorithm. Finally, a rapid screening model for SS and HC, as well as DN and HC, was developed and used to perform controlled experiments. The results showed that the diagnostic accuracy, sensitivity and selectivity for SERS technology combined with machine learning algorithms reached 90.7%, 93.4% and 86.7% for SS/HC and 89.3%, 95.6% and 80% for DN/HC, respectively. The results of this study show that the composite substrate has excellent potential to be developed into a commercially available SERS chip for medical testing.
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Nanopartículas Metálicas , Silício , Humanos , Análise Espectral Raman/métodos , Prata , PorosidadeRESUMO
Background: There is a growing public concern about diabetic kidney disease (DKD), which poses a severe threat to human health and life. It is important to discover noninvasive and sensitive immune-associated biomarkers that can be used to predict DKD development. ScRNA-seq and transcriptome sequencing were performed here to identify cell types and key genes associated with DKD. Methods: Here, this study conducted the analysis through five microarray datasets of DKD (GSE131882, GSE1009, GSE30528, GSE96804, and GSE104948) from gene expression omnibus (GEO). We performed single-cell RNA sequencing analysis (GSE131882) by using CellMarker and CellPhoneDB on public datasets to identify the specific cell types and cell-cell interaction networks related to DKD. DEGs were identified from four datasets (GSE1009, GSE30528, GSE96804, and GSE104948). The regulatory relationship between DKD-related characters and genes was evaluated by using WGCNA analysis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) datasets were applied to define the enrichment of each term. Subsequently, immune cell infiltration between DKD and the control group was identified by using the "pheatmap" package, and the connection Matrix between the core genes and immune cell or function was illuminated through the "corrplot" package. Furthermore, RcisTarget and GSEA were conducted on public datasets for the analysis of the regulation relationship of key genes and it revealed the correlation between 3 key genes and top the 20 genetic factors involved in DKD. Finally, the expression of key genes between patients with 35 DKD and 35 healthy controls were examined by ELISA, and the relationship between the development of DKD rate and hub gene plasma levels was assessed in a cohort of 35 DKD patients. In addition, we carried out immunohistochemistry and western blot to verify the expression of three key genes in the kidney tissue samples we obtained. Results: There were 8 cell types between DKD and the control group, and the number of connections between macrophages and other cells was higher than that of the other seven cell groups. We identified 356 different expression genes (DEGs) from the RNA-seq, which are enriched in urogenital system development, kidney development, platelet alpha granule, and glycosaminoglycan binding pathways. And WGCNA was conducted to construct 13 gene modules. The highest correlations module is related to the regulation of cell adhesion, positive regulation of locomotion, PI3K-Akt, gamma response, epithelial-mesenchymal transition, and E2F target signaling pathway. Then we overlapped the DEGs, WGCNA, and scRNA-seq, SLIT3, PDE1A and CFH were screened as the closely related genes to DKD. In addition, the findings of immunological infiltration revealed a remarkable positive link between T cells gamma delta, Macrophages M2, resting mast cells, and the three critical genes SLIT3, PDE1A, and CFH. Neutrophils were considerably negatively connected with the three key genes. Comparatively to healthy controls, DKD patients showed high levels of SLIT3, PDE1A, and CFH. Despite this, higher SLIT3, PDE1A, and CFH were associated with an end point rate based on a median follow-up of 2.6 years. And with the gradual deterioration of DKD, the expression of SLIT3, PDE1A, and CFH gradually increased. Conclusions: The 3 immune-associated genes could be used as diagnostic markers and therapeutic targets of DKD. Additionally, we found new pathogenic mechanisms associated with immune cells in DKD, which might lead to therapeutic targets against these cells.
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Diabetes Mellitus , Nefropatias Diabéticas , Humanos , Nefropatias Diabéticas/genética , Fosfatidilinositol 3-Quinases , Transcriptoma , Genes Reguladores , Western BlottingRESUMO
Human bone is composed of cortical bone and cancellous bone. The interior portion of natural bone is cancellous with a porosity of 50%-90%, but the outer layer is made of dense cortical bone, of which porosity was not higher than 10%. Porous ceramics were expected to be research hotspot in bone tissue engineering by virtue of their similarity to the mineral constituent and physiological structure of human bone. However, it is challenging to utilize conventional manufacturing methods to fabricate porous structures with precise shapes and pore sizes. Three-dimensional (3D) printing of ceramics is currently the latest research trend because it has many advantages in the fabrication of porous scaffolds, which can meet the requirements of cancellous bone strength, arbitrarily complex shapes, and individualized design. In this study, ß-tricalcium phosphate (ß-TCP)/titanium dioxide (TiO2) porous ceramics scaffolds were fabricated by 3D gel-printing sintering for the first time. The chemical constituent, microstructure, and mechanical properties of the 3D-printed scaffolds were characterized. After sintering, a uniform porous structure with appropriate porosity and pore sizes was observed. Besides, biological mineralization activity and biocompatibility were evaluated by in vitro cell assay. The results demonstrated that the incorporation of TiO2 (5 wt%) significantly improved the compressive strength of the scaffolds, with an increase of 283%. Additionally, the in vitro results showed that the ß-TCP/TiO2 scaffold had no toxicity. Meanwhile, the adhesion and proliferation of MC3T3-E1 cells on scaffolds were desirable, revealing that the ß-TCP/TiO2 scaffolds can be used as a promising candidate for repair scaffolding in orthopedics and traumatology.
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Técnicas Biossensoriais , Antígenos de Grupos Sanguíneos , Humanos , Imunoensaio , Isoanticorpos , EritrócitosRESUMO
Although since the 1980s, the mortality of coronary heart disease(CHD) has obviously decreased due to the rise of coronary intervention, the mortality and disability of CHD were still high in some countries. Etiological studies of acute myocardial infarction(AMI) and CHD were extremely important. In this study, we used two-sample Mendelian randomization(TSMR) method to collect GWAS statistics of osteoprotegerin (OPG), AMI and CHD to reveal the causal relationship between OPG and these two diseases. In total, we identified 7 genetic variants associated with AMI and 7 genetic variants associated with CHD that were not found to be in linkage disequilibrium(LD; r 2 < 0.001). Evidence of a positive effect of an OPG genetic susceptibility on AMI was discovered(IVW OR = 0.877; 95% CI = 0.787-0.977; p = 0.017; 7 SNPs) and CHD (IVW OR = 0.892; 95% CI = 0.803-0.991; p = 0.033; 7 SNPs). After removing the influence of rs1385492, we found that there was a correlation between OPG and AMI/CHD (AMI: weighted median OR = 0.818;95% CI = 0.724-0.950; p = 0.001; 6SNPs;CHD: weighted median OR = 0.842; 95% CI = 0.755-0.938; p = 1.893 × 10-3; 6SNPs). The findings of our study indicated that OPG had a tight genetic causation association with MI or CHD. This genetic causal relationship presented us with fresh ideas for the etiology of AMI and CHD, which is an area of research that will continue in the future.
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Fibrosis is an excessive accumulation of extracellular matrix (ECM) that may cause severe organ dysfunction. Nitric oxide (NO), a multifunctional gaseous signaling molecule, may inhibit fibrosis, and delivery of NO may serve as a potential antifibrotic strategy. However, major limitations in the application of NO to treat fibrotic diseases include its nonspecificity, short half-life and low availability in fibrotic tissue. Herein, we aimed to develop a stimuli-responsive drug carrier to deliver NO to halt kidney fibrosis. We manufactured a nanoparticle (NP) composed of pH-sensitive poly[2-(diisopropylamino)ethyl methacrylate (PDPA) polymers to encapsulate a NO donor, a dinitrosyl iron complex (DNIC; [Fe2(µ-SEt)2(NO)4]). The NPs were stable at physiological pH 7.4 but disintegrated at pH 4.0-6.0. The NPs showed significant cytotoxicity to cultured human myofibroblasts and were able to inhibit the activation of myofibroblasts, as indicated by a lower expression level of α-smooth muscle actin and the synthesis of a major ECM component, collagen I, in cultured human myofibroblasts. When given to mice treated with unilateral ureteral ligation/obstruction (UUO) to induce kidney fibrosis, these NPs remained in blood at a stable concentration for as long as 24 h and might enter the fibrotic kidneys to suppress myofibroblast activation and collagen I production, leading to a 70% reduction in the fibrotic area. In summary, our strategy to assemble a NO donor, the iron nitrosyl complex DNIC, into pH-responsive NPs proves effective in treating renal fibrosis and warrants further investigation for its therapeutic potential.
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Nefropatias , Obstrução Ureteral , Camundongos , Humanos , Animais , Rim , Óxido Nítrico/metabolismo , Nefropatias/tratamento farmacológico , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Colágeno Tipo I/metabolismo , Fibrose , Concentração de Íons de Hidrogênio , Camundongos Endogâmicos C57BLRESUMO
Hydrogen, a clean and flexible energy carrier, can be efficiently produced by electrocatalytic water splitting. To accelerate the sluggish hydrogen evolution reaction and oxygen evolution reaction kinetics in the splitting process, highly active electrocatalysts are essential for lowering the energy barriers, thereby improving the efficiency of overall water splitting. Combining the distinctive advantages of metal-organic frameworks (MOFs) with the physicochemical properties of 2D materials such as large surface area, tunable structure, accessible active sites, and enhanced conductivity, 2D MOFs have attracted intensive attention in the field of electrocatalysis. Different strategies, such as improving the conductivities of MOFs, reducing the thicknesses of MOF nanosheets, and integrating MOFs with conductive particles or substrates, are developed to promote the catalytic performances of pristine MOFs. This review summarizes the recent advances of pristine 2D MOF-based electrocatalysts for water electrolysis. In particular, their intrinsic electrocatalytic properties are detailly analyzed to reveal important roles of inherent MOF active centers, or other in situ generated active phases from MOFs responsible for the catalytic reactions. Finally, the challenges and development prospects of pristine 2D MOFs for the future applications in overall water splitting are discussed.