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Familial hypercholesterolemia (FH) is one of the most prevalent monogenetic disorders leading to cardiovascular disease (CVD) worldwide. Mutations in Ldlr, encoding a membrane-spanning protein, account for the majority of FH cases. No effective and safe clinical treatments are available for FH. Adenine base editor (ABE)-mediated molecular therapy is a promising therapeutic strategy to treat genetic diseases caused by point mutations, with evidence of successful treatment in mouse disease models. However, due to the differences in the genomes between mice and humans, ABE with specific sgRNA, a key gene correction component, cannot be directly used to treat FH patients. Thus, we generated a knock-in mouse model harboring the partial patient-specific fragment and including the Ldlr W490X mutation. LdlrW490X/W490X mice recapitulated cholesterol metabolic disorder and clinical manifestations of atherosclerosis associated with FH patients, including high plasma low-density lipoprotein cholesterol levels and lipid deposition in aortic vessels. Additionally, we showed that the mutant Ldlr gene could be repaired using ABE with the cellular model. Taken together, these results pave the way for ABE-mediated molecular therapy for FH.
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Hipercolesterolemia , Hiperlipoproteinemia Tipo II , Humanos , Camundongos , Animais , RNA Guia de Sistemas CRISPR-Cas , Hiperlipoproteinemia Tipo II/genética , Hiperlipoproteinemia Tipo II/terapia , Mutação , Hipercolesterolemia/genética , Colesterol , Receptores de LDL/genética , Receptores de LDL/metabolismoRESUMO
Disulfidptosis is a novel form of programmed cell death involved in migration and invasion of cancer cells, but few studies investigated the roles of genetic variants in disulfidptosis-related genes in survival of patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). We used Cox proportional hazards regression analyses, Kaplan-Meier curves and receiver operating characteristic curves to assess effects of genetic variants in 14 disulfidptosis-related genes on overall survival of 866 HBV-HCC patients. The Bayesian false discovery probability was used for multiple testing corrections. We also investigated biological mechanisms of the significant variants through expression quantitative trait loci analyses using the data from publicly available databases, luciferase reporter assays and differential expression analyses. As a result, we identified two independently functional single nucleotide polymorphisms (SNPs) (INF2 rs4072285 Gâ >â A and INF2 rs4444271 Aâ >â T) that predicted overall survival of HBV-HCC patients, with adjusted hazard ratios of 1.60 (95% CIâ =â 1.22-2.11, Pâ =â 0.001) and 1.50 (95% CIâ =â 1.80-1.90, Pâ <â 0.001), respectively, after multiple testing correction. Luciferase reporter assays indicated that both INF2 rs4072285 A and INF2 rs4444271 T alleles increased INF2 mRNA expression levels (Pâ <â 0.001) that were also higher in HCC tumor tissues than in adjacent normal tissues (Pâ <â 0.001); such elevated INF2 expression levels were associated with a poorer survival of HBV-HCC patients (Pâ <â 0.001) in the TCGA database. In summary, this study supported that INF2 rs4072285 and INF2 rs4444271 may be novel biomarkers for survival of HBV-HCC patients.
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Carcinoma Hepatocelular , Forminas , Hepatite B , Neoplasias Hepáticas , Humanos , Teorema de Bayes , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Forminas/genética , Hepatite B/complicações , Hepatite B/genética , Vírus da Hepatite B/patogenicidade , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , LuciferasesRESUMO
BACKGROUND: Potentially modifiable risk factors for hepatocellular carcinoma (HCC) have been investigated in observational epidemiology studies in East Asian and European populations, whereas the causal associations of most of these risk factors remain unclear. METHODS: We collected genome-wide association summary statistics of 22 modifiable risk factors in East Asians and 33 risk factors in Europeans. Genetic summary statistics of HCC were sourced from the Biobank Japan study (1,866 cases and 195,745 controls) for East Asians, and the deCODE genetics study (406 cases and 49,302 controls) and the UK Biobank (168 cases and 372 016 controls) for Europeans. Two-sample Mendelian randomization (MR) analyses were performed independently for East Asian and European populations. RESULTS: In East Asians, genetically predicted alcohol frequency, ever drinkers, aspartate aminotransferase (AST), hypothyroidism, chronic hepatitis B, and chronic hepatitis C, metabolic dysfunction-associated steatotic liver disease (MASLD), and autoimmune hepatitis were significantly associated with an increased HCC risk (P < 0.05/22). Among European population, alanine transaminase, AST, MASLD, percent liver fat, and liver iron content were significantly associated with a higher risk of HCC (P < 0.05/33). The replication dataset and meta-analysis further confirmed these results. CONCLUSIONS: Although East Asian and European populations have different factors for HCC, their common modifiable risk factors AST and MASLD for HCC, offer valuable insights for targeted intervention strategies to mitigate society burden of HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Análise da Randomização Mendeliana , Feminino , Humanos , Masculino , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/epidemiologia , Estudos de Casos e Controles , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Japão/epidemiologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/epidemiologia , Polimorfismo de Nucleotídeo Único , Fatores de Risco , População Branca/genética , População do Leste Asiático/genéticaRESUMO
CRISPR-Cas9 is a versatile gene editing tool with a broad application of basic research and clinical therapeutics. However, the potential impact caused by off-target effects remains a critical bottleneck. The small Cas9 ortholog from Staphylococcus auricularis (SauriCas9) was identified, which recognizes a 5'-NNGG-3' protospacer adjacent motif (PAM), exhibiting high activity for genome editing. Recently, we also reported enhanced-fidelity Staphylococcus aureus Cas9 (efSaCas9), which harbors a single mutation N260D. Protein sequence alignment revealed that SauriCas9 has 62.4% sequence identity with SaCas9. Because SauriCas9 is more flexible in recognizing the target sequence with PAM of 5'-NNGG-3' than SaCas9 of 5'-NNGRRT-3' PAM, we sought to test whether key mutation(N260D) or adjacent residue mutation in efSaCas9 can be appliable to SauriCas9. With this concept, two engineered SauriCas9 variants (SauriCas9-HF1, harboring the N269D mutation; SauriCas9-HF2, harboring the D270N mutation) dramatically improved targeting specificity by targeted deep sequencing and GUIDE-seq. At certain sites, reduced off-target effects (approximately 61.6- and 111.9-fold improvements) of SauriCas9-HF2 compared with wild-type SauriCas9 were observed. Overall, two identified SauriCas9 variants (SauriCas9-HF1 and SauriCas9-HF2) expand the utility of the CRISPR toolkit for research and therapeutic applications.
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Sistemas CRISPR-Cas , Infecções Estafilocócicas , Humanos , Staphylococcus/genética , Staphylococcus aureus/genéticaRESUMO
The adsorption of organic polymers onto the surface of graphene oxide is known to improve its dispersibility in cement-based materials. However, the mechanism of this improvement at the atomic level is not yet fully understood. In this study, we employ a combination of DFT static calculation and umbrella sampling to explore the reactivity of polymers and investigate the effects of varying amounts of phenyl groups on their adsorption capacity on the surface of graphene oxide. Quantitative analysis is utilized to study the structural reconstruction and charge transfer caused by polymers from multiple perspectives. The interfacial reaction between the polymer and graphene oxide surface is further clarified, indicating that the adsorption process is promoted by hydrogen bond interactions and π-π stacking effects. This study sheds light on the adsorption mechanism of polymer-graphene oxide systems and has important implications for the design of more effective graphene oxide dispersants at the atomic level.
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Among small-molecule CDK4/6 inhibitors (palbociclib, ribociclib, and abemaciclib) approved for metastatic breast cancers, abemaciclib has a more tolerable adverse effects in clinic. This is attributable to preferential inhibition of CDK4 over CDK6. In our search for a biased CDK4 inhibitor, we discovered a series of pyrimidine-indazole inhibitors. SAR studies led us to TQB3616 as a preferential CDK4 inhibitor. TQB3616 exhibited improvements in both enzymatic and cellular proliferation inhibitory potency when tested side-by-side with the FDA approved palbociclib and abemaciclib. TQB3616 also possessed favorable PK profile in multiple species. These differentiated properties, together with excellent GLP safety profile warranted TQB3616 moving to clinic. TQB3616 entered into clinical development in 2019 and currently in phase III clinical trials (NCT05375461, NCT05365178).
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Proliferação de Células , Quinase 4 Dependente de Ciclina , Inibidores de Proteínas Quinases , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 4 Dependente de Ciclina/metabolismo , Humanos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/síntese química , Relação Estrutura-Atividade , Estrutura Molecular , Proliferação de Células/efeitos dos fármacos , Animais , Descoberta de Drogas , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Relação Dose-Resposta a Droga , Pirimidinas/química , Pirimidinas/farmacologia , Pirimidinas/síntese química , Ratos , Ensaios de Seleção de Medicamentos Antitumorais , Avaliação Pré-Clínica de MedicamentosRESUMO
Trimethylation on histone H3 lysine 27 (H3K27me3) by Polycomb repressive complex 2 (PRC2) regulates the balance between self-renewal and differentiation of embryonic stem cells (ESCs). The mechanisms controlling the activity and recruitment of PRC2 are largely unknown. Here we demonstrate that the founding member of the Jumonji family, JMJ (JUMONJI or JARID2), is associated with PRC2, colocalizes with PRC2 and H3K27me3 on chromatin, and modulates PRC2 function. In vitro JMJ inhibits PRC2 methyltransferase activity, consistent with increased H3K27me3 marks at PRC2 targets in Jmj(-/-) ESCs. Paradoxically, JMJ is required for efficient binding of PRC2, indicating that the interplay of PRC2 and JMJ fine-tunes deposition of the H3K27me3 mark. During differentiation, activation of genes marked by H3K27me3 and lineage commitments are delayed in Jmj(-/-) ESCs. Our results demonstrate that dynamic regulation of Polycomb complex activity orchestrated by JMJ balances self-renewal and differentiation, highlighting the involvement of chromatin dynamics in cell-fate transitions.
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Células-Tronco Embrionárias/citologia , Proteínas do Tecido Nervoso/metabolismo , Proteínas Repressoras/metabolismo , Animais , Diferenciação Celular , Montagem e Desmontagem da Cromatina , Células HeLa , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Humanos , Camundongos , Complexo Repressor Polycomb 2 , Proteínas do Grupo PolycombRESUMO
Aqueous emulsion polymerization is a robust technique for preparing nanoparticles of block copolymers; however, it typically yields spherical nanoassemblies. The scale preparation of nanoassemblies with nonspherical high-order morphologies is a challenge, particularly 2D core-shell nanosheets. In this study, the polymerization-induced self-assembly (PISA) and crystallization-driven self-assembly (CDSA) are combined to demonstrate the preparation of 2D nanosheets and their aggregates via aqueous reversible addition-fragmentation chain transfer (RAFT) emulsion polymerization. First, the crucial crystallizable component for CDSA, hydroxyethyl methacrylate polycaprolactone (HPCL) macromonomer is synthesized by ring opening polymerization (ROP). Subsequently, the RAFT emulsion polymerization of HPCL is conducted to generate crystallizable nanomicelles by a grafting-through approach. This PISA process simultaneously prepared spherical latices and bottlebrush block copolymers comprising poly(N',N'-dimethylacrylamide)-block-poly(hydroxyethyl methacrylate polycaprolactone) (PDMA-b-PHPCL). The latexes are now served as seeds for inducing the formation of 2D hexagonal nanosheets, bundle-shaped and flower-like aggregation via the CDSA of PHPCL segments and unreacted HPCL during cooling. Electron microscope analysis trace the morphology evolution of these 2D nanoparticles and reveal that an appropriate crystallized component of PHPCL blocks play a pivotal role in forming a hierarchical structure. This work demonstrates significant potential for large-scale production of 2D nanoassemblies through RAFT emulsion polymerization.
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Hepatocellular carcinoma (HCC) is one of the most common malignant tumors with a high mortality rate. The 5-methylcytosine (m5C), a type of RNA modification, plays crucial regulatory roles in HCC carcinogenesis, metastasis, and prognosis. However, a few studies have investigated the effect of genetic variants in m5C modification genes on survival of patients with hepatitis B virus (HBV)-related HCC. In the present study, we evaluated associations between 144 SNPs in 15 m5C modification genes and overall survival (OS) in 866 patients with the HBV-related HCC. Expression quantitative trait loci (eQTL) analysis and differential expression analysis were conducted to investigate biological mechanisms. As a result, we identified that two SNPs (NSUN7 rs2437325 A > G and TRDMT1 rs34434809 G > C) were significantly associated with HBV-related HCC OS with adjusted allelic hazards ratios of 1.25 (95% confidence interval = 1.05-1.48 and P = 0.011) and 1.19 (1.02-1.38 and P = 0.027), respectively, with a trend of combined risk genotypes (Ptrend < 0.001). Moreover, the results of eQTL analyses showed that both NSUN7 rs2437325 G and TRDMT1 rs34434809 C alleles were associated with a reduced mRNA expression level in 208 normal liver tissues (P = 0.007 and P < 0.001, respectively). Taken together, genetic variants in the m5C modification genes may be potential prognostic biomarkers of HBV-related HCC after hepatectomy, likely through mediating the mRNA expression of corresponding genes.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Vírus da Hepatite B/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Genótipo , Prognóstico , RNA Mensageiro/genéticaRESUMO
OBJECTIVE: The associations between plasma vitamin B12 level and anemia under different dietary patterns in elderly Chinese people are poorly understood. We aimed to examine the associations between plasma vitamin B12 levels and anemia under different dietary patterns in adults aged 65 years and older in nine longevity areas in China. METHODS: A total of 2405 older adults completed a food frequency questionnaire at the same time as a face-to-face interview. The dietary diversity score (DDS) was assessed based on the food frequency questionnaire, with the low DDS group referring to participants with a DDS score ≤ 4 points. Vitamin B12 levels were divided into two groups of high (>295 pg/mL) and low (≤ 295 pg/mL) with the median used as the cut-off point. Sub-analyses were also performed on older adults divided into tertiles of vitamin B12 levels: low (< 277 pg/mL), medium (277-375 pg/mL) and high (> 375 pg/mL) to study the association of these levels with anemia. RESULTS: Six hundred ninety-five (28.89%) of these people were diagnosed with anemia and had a mean age of 89.3 years. Higher vitamin B12 levels were associated with a decreased risk of anemia (multi-adjusted OR, 0.59, [95% CI, 0.45 ~ 0.77] P < 0.001) in older adults with a low DDS, whereas no significant association between vitamin B12 levels and anemia was found in older adults with a high DDS in a full-model after adjustment for various confounding factors (multi-adjusted OR, 0.88, [95% CI, 0.65 ~ 1.19], P = 0.41). CONCLUSION: The relationship between vitamin B12 levels and the prevalence of anemia was significant only when the level of dietary diversity in the older adults was relatively low. The dietary structure of the population should be taken into consideration in combination in order to effectively improve anemia status by supplementing vitamin B12.
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Anemia , Deficiência de Vitamina B 12 , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Anemia/diagnóstico , Anemia/epidemiologia , Biomarcadores , Estudos de Coortes , Vitamina B 12 , Deficiência de Vitamina B 12/diagnóstico , Deficiência de Vitamina B 12/epidemiologia , VitaminasRESUMO
OBJECTIVE: Currently, there is lack of a consistent and highly enriched source for docosapentaenoic acid (n-3 DPA, C22:5), and this work report the isolation of microorganism that naturally produces n-3 DPA. RESULTS: In this work, we screened microorganisms in our culture collections with the goal to isolate a strain with high levels of n-3 DPA. We isolated a strain of Sphaeroforma arctica that produces up to 11% n-3 DPA in total fatty acid and has a high n-3 DPA to DHA/EPA ratio. The cell growth of the isolated strain was characterized using microscopy imaging and flow cytometer technologies to confirm the coenocytic pattern of cell divisions previously described in S. arctica. Our novel isolate of S. arctica grew more robustly and produced significantly more n-3 DPA compared to previously isolated and described strains indicating the uniqueness of the discovered strain. CONCLUSION: Overall, this work reports a first isolate n-3 DPA producing microorganism and establishes the foundation for future strain improvement and elucidation of the physiological function of this LC-PUFA for human nutrition and health.
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Ácidos Graxos Insaturados , Ácidos Graxos Insaturados/metabolismo , Estramenópilas/metabolismo , Estramenópilas/isolamento & purificaçãoRESUMO
The development of fluorescent molecular imprinting sensors for direct, rapid, and sensitive detection of small organic molecules in aqueous systems has always presented a significant challenge in the field of detection. In this study, we successfully prepared a hydrophilic colloidal molecular imprinted polymer (MIP) with 2,4-dichlorophenoxyacetic acid (2,4-D) using a one-pot approach that incorporated polyglycerol methacrylate (PGMMA-TTC), a hydrophilic macromolecular chain transfer agent, to mediate reversible addition-fragmentation chain transfer precipitation polymerization (RAFTPP). To simplify the polymerization process while achieving ratiometric fluorescence detection, red fluorescent CdTe quantum dots (QDs) and green fluorescent nitrobenzodiazole (NBD) were introduced as fluorophores (with NBD serving as an enhancer to the template and QDs being inert). This strategy effectively eliminated background noise and significantly improved detection accuracy. Uniform-sized MIP microspheres with high surface hydrophilicity and incorporated ratiometric fluorescent labels were successfully synthesized. In aqueous systems, the hydrophilic ratio fluorescent MIP exhibited a linear response range from 0 to 25 µM for the template molecule 2,4-D with a detection limit of 0.13 µM. These results demonstrate that the ratiometric fluorescent MIP possesses excellent recognition characteristics and selectivity towards 2,4-D, thus, making it suitable for selective detection of trace amounts of pesticide 2,4-D in aqueous systems.
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BACKGROUND: Although laser Doppler imaging (LDI) accurately delineates a hypoperfused area to help target hyaluronidase treatment, laser speckle contrast imaging (LSCI) is more appropriate for assessing microvascular hemodynamics and has greater reproducibility than LDI. This study investigated the use of LSCI in the evaluation and treatment of six patients who developed vascular complications after facial dermal filler injections. METHODS: The areas of vascular occlusion were accurately defined in real time by LSCI and were more precise than visual inspections or photographic evidence for guiding needling and hyaluronidase treatment. RESULTS: All patients had achieved satisfactory outcomes as early as Day 2 of treatment and no procedure-related complications were reported after a median follow-up of 9.5 (7-37) days. CONCLUSION: LSCI accurately and noninvasively delineated vascular occlusions in real time among patients experiencing complications of facial dermal filler injections. Moreover, LSCI was more accurate than visual and photographic evaluations. Clinicians can use LSCI to reliably follow-up therapeutic outcomes after salvage interventions for vascular occlusions. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Técnicas Cosméticas , Preenchedores Dérmicos , Humanos , Preenchedores Dérmicos/efeitos adversos , Imagem de Contraste de Manchas a Laser , Hialuronoglucosaminidase , Reprodutibilidade dos Testes , Indução Percutânea de Colágeno , Técnicas Cosméticas/efeitos adversos , Ácido HialurônicoRESUMO
Ethanamizuril (EZL) is a new anticoccidial drug developed by our Shanghai Veterinary Research Institute. Since EZL is almost insoluble in water, we conducted a study to improve the solubility of EZL by forming inclusion complexes with ß-cyclodextrin (ß-CD) and hydroxypropyl-ß-cyclodextrin (HP-ß-CD). In this study, we performed molecular docking and then systematically compared the interactions of EZL with ß-CD and HP-ß-CD in both aqueous solution and the solid state, aiming to elucidate the solubilization effect and mechanism of cyclodextrins (CDs). The interactions were also examined in the solid state using DSC, PXRD, and FT-IR. The interactions of EZL with CDs in an aqueous solution were investigated using PSA, UV-vis spectroscopy, MS, 1H NMR, and 2D ROESY. The results of phase solubility experiments revealed that both ß-CD and HP-ß-CD formed inclusion complexes with EZL in a 1:1 molar ratio. Among them, HP-ß-CD exhibited higher Kf (stability constant) and CE (complexation efficiency) values as well as a stronger solubilization effect. Furthermore, the two cyclodextrins were found to interact with EZL in a similar manner. The results of our FT-IR and 2D ROESY experiments are in agreement with the theoretical results derived from molecular simulations. These results indicated that intermolecular hydrogen bonds existing between the C=O group on the triazine ring of EZL and the O-H group of CDs, as well as the hydrophobic interactions between the hydrogen on the benzene ring of EZL and the hydrogen of CDs, played crucial roles in the formation of EZL/CD inclusion complexes. The results of this study can lay the foundation for the future development of high-concentration drinking water delivery formulations for EZL.
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The sluggish kinetics of lithium-sulfur (Li-S) batteries severely impedes the application in extreme conditions. Bridging the sulfur cathode and lithium anode, the electrolyte plays a crucial role in regulating kinetic behaviors of Li-S batteries. Herein, we report a multifunctional electrolyte additive of phenyl selenium bromide (PhSeBr) to simultaneously exert positive influences on both electrodes and the electrolyte. For the cathode, an ideal conversion routine with lower energy barrier can be attained by the redox mediator and homogeneous catalyst derived from PhSeBr, thus improving the reaction kinetics and utilization of sulfur. Meanwhile, the presence of Se-Br bond helps to reconstruct a loose solvation sheath of lithium ions and a robust bilayer SEI with excellent ionic conductivity, which contributes to reducing the de-solvation energy and simultaneously enhancing the interfacial kinetics. The Li-S battery with PhSeBr displays superior long cycling stability with a reversible capacity of 1164.7â mAh g-1 after 300â cycles at 0.5â C rate. And the pouch cell exhibits a maximum capacity of 845.3â mAh and a capacity retention of 94.8 % after 50â cycles. Excellent electrochemical properties are also obtained in extreme conditions of high sulfur loadings and low temperature of -20 °C. This work demonstrates the versatility and practicability of the special additive, striking out an efficient but simple method to design advanced Li-S batteries.
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How Nature synthesizes enantiomerically pure substances from achiral or racemic resources remains a mystery. In this study, we aimed to emulate this natural phenomenon by constructing chiral tetrahedral cages through self-assembly, achieved by condensing two achiral compounds-a trisamine and a trisaldehyde. The occurrence of intercomponent CHâ â â π interactions among the phenyl building blocks within the cage frameworks results in twisted conformations, imparting planar chirality to the tetrahedrons. In instances where the trisaldehyde precursor features electron-withdrawing ester side chains, we observed that the intermolecular CHâ â â π forces are strong enough to prevent racemization. To attain enantioselective self-assembly, a chiral amine was introduced during the imine formation process. The addition of three equivalents of chiral amino mediator to one equivalent of the achiral trisaldehyde precursor formed a trisimino intermediate. This chiral compound was subsequently combined with the achiral trisamino precursor, leading to an imine exchange reaction that releasing the chiral amino mediator and formation of the tetrahedral cage with an enantiomeric excess (ee) of up to 75 %, exclusively composed of achiral building blocks. This experimental observation aligns with theoretical calculations based on the free energies of related cage structures. Moreover, since the chiral amine was not consumed during the imine exchange cycle, it enabled the enantioselective self-assembly of the tetrahedral cage for multiple cycles when new batches of the achiral trisaldehyde and trisamino precursors were successively added.
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Cysteinyl-tRNA synthetase (CysRS) catalyzes the aminoacylation reaction of cysteine to its cognate tRNACys in the first step of protein translation. It is found that CysRS is different from other aaRSs as it transfers cysteine without the need for an editing reaction, which is not applicable in the case of serine despite the similarity in their structures. Surprisingly, the reasons why CysRS has high amino acid specificity are not clear yet. In this research, the binding configurations of Cys-AMP and its near-cognate amino acid Ser-AMP with CysRS are compared by Molecular Dynamics (MD). The results reveal that CysRS screens the substrate Cys-AMP to a certain extent in the process of combination and recognition, thus providing a guarantee for the high selectivity of the next reaction. While Ser-AMP is in a folded state in CysRS. In the meanwhile, the interaction between Cys-AMP and Zn963 in CysRS is much stronger than Ser-AMP. The substrate-assisted aminoacylation mechanism in CysRS is also explored by Quantum Mechanics/Molecular Mechanics (QM/MM) modeling. According to the QM/MM potential energies, the energy barrier of TSCys-AMP is 91.75 kJ/mol, while that of TSSer-AMP is close to 150 kJ/mol. Based on thermochemistry calculations, it is found that the product of Cys-AMP is more stable than the reactant. In contrast, Ser-AMP has a reactant that is more stable than its product. As a result, it reflects that the specificity of CysRS originates from both the kinetic and thermodynamical perspectives of the reaction. Our investigations demonstrate comprehensively on how CysRS recognizes and catalyzes the substrate Cys-AMP, hoping to provide some guidance for researchers in this area.
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Aminoacil-tRNA Sintetases , Simulação de Dinâmica Molecular , Cisteína , Aminoacil-tRNA Sintetases/química , Aminoacil-tRNA Sintetases/genética , Aminoacil-tRNA Sintetases/metabolismo , Aminoácidos/química , Especificidade por SubstratoRESUMO
Hepatocellular carcinoma (HCC) ranks the third leading cause of cancer deaths with a dismal 5-year survival rate. The mitogen-activated protein kinase (MAPK) signaling pathway is abnormally activated in HCC to promote growth and aggressive metastatic potential of cancer cells. Therefore, genetic variants in the MAPK signaling pathway may serve as potential predictors of Hepatitis B virus (HBV)-related HCC survival. In the present study, we performed a two-stage survival analysis to evaluate the associations between 10,912 single nucleotide polymorphisms (SNPs) in 79 MAPK signaling pathway genes and the overall survival (OS) of 866 HBV-related HCC patients, followed by functional annotation. In combined datasets, we identified two novel and potential functional SNPs (RPS6KA4 rs600377 T>G and MAP2K5 rs17300363 A>C) as prognostic factors for HBV-related HCC, with adjusted allelic hazards ratios of 1.24 (95% confidence interval [CI] = 1.05-1.46, p = 0.010) and 1.48 (1.15-1.91, p = 0.001), respectively. Furthermore, their combined risk genotypes also predicted a poor survival in a dose-response manner in the combined data set (Ptrend < 0.001). Additional functional analysis showed that RPS6KA4 rs600377 G and MAP2K5 rs17300363 C alleles were associated with elevated mRNA expression levels of the corresponding genes in normal tissues. These results provide new insights into the role of genetic variants in the MAPK signaling pathway genes in HBV-related HCC survival.
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Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Predisposição Genética para Doença , Genótipo , Vírus da Hepatite B , Hepatite B Crônica/complicações , Neoplasias Hepáticas/patologia , Proteínas Quinases Ativadas por Mitógeno/genética , Polimorfismo de Nucleotídeo Único , Transdução de SinaisRESUMO
The RAS pathway participates in the cascade of proliferation and cell division process, and the activated RAS pathway can lead to tumorigenesis including hepatocellular carcinoma (HCC). However, few studies have explored the effects of genetic variants in the RAS pathway-related genes on the survival of patients with HBV-related HCC. In the present study, we assessed the associations between 11,658 single-nucleotide polymorphisms (SNPs) in 62 RAS pathway genes and the overall survival (OS) of 866 HBV-related HCC individuals, which were randomly split (1:1) into discovery and validation datasets. As a result, three potentially functional SNPs were identified, based on multivariable cox proportional hazards regression analyses, in SOS Ras/Rho guanine nucleotide exchange factor 2 (SOS2, rs4632055 A > G), Ras protein-specific guanine nucleotide releasing factor 2 (RASGRF2, rs26418A > G) and mitogen-activated protein kinase 1 (MAP2K1,rs57120695 C > T), which were significantly and independently associated with OS of HBV-related HCC patients [adjusted hazards ratios (HRs) of 1.42, 1.32 and 1.50, respectively; 95% confidence intervals (CI), 1.14 to 1.76, 1.15 to 1.53 and 1.15 to 1.97, respectively; P = 0.001, < 0.001 and 0.003, respectively]. Additionally, the joint effects as the unfavorable genotypes of these three SNPs showed a significant association with the poor survival of HCC (trend test P < 0.001). The expression quantitative trait loci (eQTL) analysis further revealed that the rs4632055 G allele and the rs26418 A allele were associated with lower mRNA expression levels of SOS2 and RASGRF2, respectively. Collectively, these potentially functional SNPs of RASGRF2, SOS2 and M2PAK1 may become potential prognostic biomarkers for HBV-related HCC after hepatectomy.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Vírus da Hepatite B/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Genótipo , Alelos , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença , MAP Quinase Quinase 1/genética , Fatores ras de Troca de Nucleotídeo Guanina/genéticaRESUMO
Reasonable regulation of the total amount and layout of land resources is the significant cornerstone for releasing the potential of land resources. This study explored the spatial layout and evolution characteristics of the Nansi Lake Basin from the perspective of land use and simulated the spatial distribution pattern under multiple scenarios in 2035 with the Future Land Use Simulation model which more effectively reflected the process of land use change in the actual situation, revealing the land use change of the Nansi Lake Basin under the influence of different human activities. Analysis indicated that the simulation results obtained using the Future Land Use Simulation model strongly agree with reality. By 2035, the magnitude and spatial distribution of land use landscapes will change significantly under three scenarios. The findings provide a reference for the adjustment of land use planning in the Nansi Lake Basin.