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Apolipoprotein H (APOH) downregulation can cause hepatic steatosis and gut microbiota dysbiosis. However, the mechanism by which APOH-regulated lipid metabolism contributes to metabolic dysfunction-associated steatotic liver disease (MASLD) remains undetermined. Herein, we aim to explore the regulatory effect of APOH, mediated through various pathways, on metabolic homeostasis and MASLD pathogenesis. We analyzed serum marker levels, liver histopathology, and cholesterol metabolism-related gene expression in global ApoH-/- C57BL/6 male mice. We used RNA sequencing and metabolomic techniques to investigate the association between liver metabolism and bacterial composition. Fifty-two differentially expressed genes were identified between ApoH-/- and WT mice. The mRNA levels of de novo lipogenesis genes were highly upregulated in ApoH-/- mice than in WT mice. Fatty acid, glycerophospholipid, sterol lipid, and triglyceride levels were elevated, while hyodeoxycholic acid levels were significantly reduced in the liver tissues of ApoH-/- mice than in those of WT mice. Microbial beta diversity was lower in ApoH-/- mice than in WT mice, and gut microbiota metabolic functions were activated in ApoH-/- mice. Moreover, ApoH transcripts were downregulated in patients with MASLD, and APOH-related differential genes were enriched in lipid metabolism. Open-source transcript-level data from human metabolic dysfunction-associated steatohepatitis livers reinforced a significant association between metabolic dysfunction-associated steatohepatitis and APOH downregulation. In conclusion, our studies demonstrated that APOH downregulation aggravates fatty liver and induces gut microbiota dysbiosis by dysregulating bile acids. Our findings offer a novel perspective on APOH-mediated lipid metabolic dysbiosis and provide a valuable framework for deciphering the role of APOH in fatty liver disease.
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Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Humanos , Masculino , Camundongos , Animais , Metabolismo dos Lipídeos/genética , beta 2-Glicoproteína I/genética , beta 2-Glicoproteína I/metabolismo , beta 2-Glicoproteína I/farmacologia , Regulação para Baixo , Disbiose/metabolismo , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fígado/metabolismo , Ácidos Graxos/metabolismoRESUMO
Integer and fractional Chern insulators have been extensively explored in correlated flat band models. Recently, the prediction and experimental observation of fractional quantum anomalous Hall (FQAH) states with spontaneous time-reversal symmetry breaking have garnered attention. While the thermodynamics of integer quantum anomalous Hall (IQAH) states have been systematically studied, our theoretical knowledge on thermodynamic properties of FQAH states has been severely limited. Here, we delve into the general thermodynamic response and collective excitations of both IQAH and FQAH states within the paradigmatic flat Chern-band model with remote band considered. Our key findings include (i) in both ν=1 IQAH and ν=1/3 FQAH states, even without spin fluctuations, the charge-neutral collective excitations would lower the onset temperature of these topological states, to a value significantly smaller than the charge gap, due to band mixing and multiparticle scattering; (ii) by employing large-scale thermodynamic simulations in FQAH states in the presence of strong interband mixing between C=±1 bands, we find that the lowest collective excitations manifest as the zero-momentum excitons in the IQAH state, whereas in the FQAH state, they take the form of magnetorotons with finite momentum; (iii) the unique charge oscillations in FQAH states are exhibited with distinct experimental signatures, which we propose to detect in future experiments.
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Novel critical phenomena beyond the Landau-Ginzburg-Wilson paradigm have been long sought after. Among many candidate scenarios, the deconfined quantum critical point (DQCP) constitutes the most fascinating one, and its lattice model realization has been debated over the past two decades. Here we apply the spherical Landau level regularization upon the exact (2+1)D SO(5) nonlinear sigma model with a topological term to study the potential DQCP therein. We perform a density matrix renormalization group (DMRG) simulation with SU(2)_{spin}×U(1)_{charge}×U(1)_{angular-momentum} symmetries explicitly implemented. Using crossing point analysis for the critical properties of the DMRG data, accompanied by quantum Monte Carlo simulations, we accurately obtain the comprehensive phase diagram of the model and find various novel quantum phases, including Néel, ferromagnet (FM), valence bond solid (VBS), valley polarized (VP) states and a gapless quantum disordered phase occupying an extended area of the phase diagram. The VBS-disorder and Néel-disorder transitions are continuous with non-Wilson-Fisher exponents. Our results show the VBS and Néel states are separated by either a weakly first-order transition or the disordered region with a multicritical point in between, thus opening up more interesting questions on the two-decade long debate on the nature of the DQCP.
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Fundamental frequency ( fo) is the most perceptually salient vocal acoustic parameter, yet little is known about how its perceptual influence varies across societies. We examined how fo affects key social perceptions and how socioecological variables modulate these effects in 2,647 adult listeners sampled from 44 locations across 22 nations. Low male fo increased men's perceptions of formidability and prestige, especially in societies with higher homicide rates and greater relational mobility in which male intrasexual competition may be more intense and rapid identification of high-status competitors may be exigent. High female fo increased women's perceptions of flirtatiousness where relational mobility was lower and threats to mating relationships may be greater. These results indicate that the influence of fo on social perceptions depends on socioecological variables, including those related to competition for status and mates.
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Voz , Adulto , Humanos , Masculino , Feminino , Homicídio , Percepção Social , Parceiros SexuaisRESUMO
BACKGROUND: While the phenotypic association between anti-Müllerian hormoneand age at menopause has been widely studied, the role of anti-Müllerian hormone in predicting the age at menopause is currently controversial, and the genetic architecture or causal relationships underlying these 2 traits is not well understood. AIM: We aimed to explore the shared genetic architecture between anti-Müllerian hormone and age at menopause, to identify shared pleiotropic loci and genes, and to investigate causal association and potential causal mediators. STUDY DESIGN: Using summary statistics from publicly available genome-wide association studies on anti-Müllerian hormone (N=7049) and age at menopause (N=201,323) in Europeans, we investigated the global genetic architecture between anti-Müllerian hormone and age at menopause through linkage disequilibrium score regression. We employed pleiotropic analysis under composite null hypothesis, Functional Mapping and Annotation of Genetic Associations, multimarker analysis of GenoMic annotation, and colocalization analysis to identify loci and genes with pleiotropic effects. Tissue enrichment analysis based on Genotype-Tissue Expression data was conducted using the Linkage Disequilibrium Score for the specific expression of genes analysis. Functional genes that were shared were additionally identified through summary data-based Mendelian randomization. The relationship between anti-Müllerian hormone and age at menopause was examined through 2-sample Mendelian randomization, and potential mediators were further explored using colocalization and metabolite-mediated analysis. RESULTS: A positive genetic association (correlation coefficient=0.88, P=1.33×10-5) was observed between anti-Müllerian hormone and age at menopause. By using pleiotropic analysis under composite null hypothesis and Functional Mapping and Annotation of Genetic Associations, 42 significant pleiotropic loci were identified that were associated with anti-Müllerian hormone and age at menopause, and 10 of these (rs10734411, rs61913600, rs2277339, rs75770066, rs28416520, rs9796, rs11668344, rs403727, rs6011452, and rs62237617) had colocalized loci. Additionally, 245 significant pleiotropic genes were identified by multimarker analysis of GenoMic annotation. Genetic associations between anti-Müllerian hormone and age at menopause were markedly concentrated in various tissues including whole blood, brain, heart, liver, muscle, pancreas, and kidneys. Further, summary data-based Mendelian randomization analysis revealed 9 genes that may have a causative effect on both anti-Müllerian hormone and age at menopause. A potential causal effect of age at menopause on anti-Müllerian hormone was suggested by 2-sample Mendelian randomization analysis, with very-low-density lipoprotein identified as a potential mediator. CONCLUSION: Our study revealed a shared genetic architecture between anti-Müllerian hormone and age at menopause, providing a basis for experimental investigations and individual therapies to enhance reproductive outcomes. Furthermore, our findings emphasized that relying solely on anti-Müllerian hormone is not sufficient for accurately predicting the age at menopause, and a combination of other factors needs to be considered. Exploring new therapeutics aimed at delaying at the onset of menopause holds promise, particularly when targeting shared genes based on their shared genetic architecture.
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In this work, Au/Bi2O3 was synthesized by loading Au nanoparticles (NPs) onto ß-Bi2O3 by a simple solution reduction method. ß-Bi2O3 was synthesized by a precipitation-thermal decomposition procedure, which results in significantly improved SERS detection limits down to 10-9 M for methylene blue (MB) and 10-7 M for methyl orange (MO) as probe molecules, comparable to those reported for the best semiconductor SERS substrates. In particular, further deposition of Au NPs (5.20% wt%) onto ß-Bi2O3 results in a two-order-of-magnitude enhancement in detection sensitivity, achieving a detection limit of 10-11 M for MB and 10-9 M for MO. Under ultraviolet/visible irradiation, the Au/Bi2O3 hybrids substrate exhibits superior self-cleaning ability due to its photocatalytic degradation ability which can be applied repeatedly to the detection of pollutants. The advanced composite substrate simultaneously achieved ultra-low mass loading of Au NPs, outstanding detection performance, good reproducibility, high stability and self-cleaning ability. The development strategy of low load noble metal coupled high performance semiconductor ß-Bi2O3 to obtain nano-hybrid materials provides a method to balance SERS sensitivity, cost effectiveness and operational stability, and can be synthesized in large quantities, which is a key step towards commercialization and has good reliability prospects.
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Adolescents' family obligation is a cultural strength that shows enduring prevalence in China. Given that the meaning of family obligation has undergone rapid changes in recent decades, it is crucial to examine the role of family obligation in adolescent adjustment in contemporary China. More importantly, although past research has investigated the consequences of family obligation on adolescents' adjustment, little is known about the antecedents of Chinese adolescents' family obligation. Using a two-wave longitudinal sample of 450 Chinese adolescents (mean age = 13.78 years, SD = .71 years; 49% female) and their parents, the current research explored two questions. First, this study examined the role of family obligation in adolescents' academic achievement, externalizing problems, and internalizing problems over early adolescence. Second, this study explored the role of parents in predicting Chinese adolescents' family obligation, specifically whether parental expectations or parental acceptance was predictive of adolescents' family obligation over time. Third, this study investigated whether family obligation is an underlying mechanism between parenting and Chinese adolescents' adjustment. Results showed that Chinese adolescents' family obligation was longitudinally associated with increased academic achievement and reduced externalizing problems. Moreover, perceived parental acceptance, but not parental expectations, was longitudinally associated with Chinese adolescents' greater family obligation. Notably, family obligation mediated the longitudinal effect of parental acceptance on Chinese adolescents' externalizing problems. By studying both the consequences and antecedents of Chinese adolescents' family obligation, this study helps provide a comprehensive understanding of this cultural strength.
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Relações Pais-Filho , Poder Familiar , Humanos , Feminino , Adolescente , Masculino , China/epidemiologia , Estudos Longitudinais , Relações Pais-Filho/etnologia , Poder Familiar/psicologia , Comportamento do Adolescente/psicologia , Sucesso Acadêmico , Pais/psicologia , População do Leste AsiáticoRESUMO
BACKGROUND: Fragility fracture is common in the elderly. Osteoblast differentiation is essential for bone healing and regeneration. Expression pattern of long non-coding RNA MIAT during fracture healing was examined, and its role in osteoblast differentiation was investigated. METHODS: 90 women with simple osteoporosis and 90 women with fragility fractures were included. Another 90 age-matched women were set as the control group. mRNA levels were tested using RT-qPCR. Cell viability was detected via CCK-8, and osteoblastic biomarkers, including ALP, OCN, Collagen I, and RUNX2 were tested via ELISA. The downstream miRNAs and genes targeted by MIAT were predicted by bioinformatics analysis, whose functions and pathways were annotated via GO and KEGG analysis. RESULTS: Serum MIAT was upregulated in osteoporosis women with high accuracy of diagnostic efficacy. Serum MIAT was even elevated in the fragility fracture group, but decreased in a time manner after operation. MIAT knockdown promoted osteogenic proliferation and differentiation of MC3T3-E1, but the influences were reversed by miR-181a-5p inhibitor. A total of 137 overlapping target genes of miR-181a-5p were predicted based on the miRDB, TargetScan and microT datasets, which were mainly enriched for terms related to signaling pathways regulating pluripotency of stem cells, cellular senescence, and osteoclast differentiation. CONCLUSIONS: LncRNA MIAT serves as a promising biomarker for osteoporosis, and promotes osteogenic differentiation via targeting miR-181a-5p.
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Biomarcadores , Diferenciação Celular , Consolidação da Fratura , Osteoblastos , RNA Longo não Codificante , RNA Longo não Codificante/genética , Humanos , Feminino , Biomarcadores/sangue , Biomarcadores/metabolismo , Consolidação da Fratura/genética , Consolidação da Fratura/fisiologia , Idoso , Diferenciação Celular/genética , Osteoblastos/metabolismo , Animais , Camundongos , MicroRNAs/genética , Osteoporose/genética , Osteoporose/metabolismo , Osteogênese/genética , Osteogênese/fisiologia , Pessoa de Meia-Idade , Fraturas por Osteoporose/genética , Proliferação de Células/genética , Regulação para CimaRESUMO
BACKGROUND: Premature ovarian insufficiency (POI) is a clinical condition characterized by ovarian dysfunction in women under 40. The etiology of most POI cases remains unidentified and is believed to be multifactorial, including factors such as autoimmunity, metabolism, infection, and genetics. POI exhibits significant genetic heterogeneity, and it can result from chromosomal abnormalities and monogenic defects. CASE PRESENTATION: The study participant, a 33-year-old woman, presented with a history of irregular menstruation that commenced two years ago, progressing to prolonged menstrual episodes and eventual cessation. The participant exhibits a rearrangement of the X chromosome, characterized by heterozygosity duplication on the long arm and heterozygosity deletion on the short arm by whole exome sequencing(WES) combined with cell chromosome detection. CONCLUSIONS: This study expands the spectrum of mutations associated with POI resulting from X chromosomal abnormalities. WES-Copy number variation analysis, in conjunction with chromosome karyotype analysis and other detection techniques, can provide a more comprehensive understanding of the genetic landscape underlying complex single or multi-system diseases.
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Esophageal cancer (EC) is a common and serious form of cancer, and while DNA methyltransferase-1 (DNMT1) promotes DNA methylation and carcinogenesis, the role of F-box protein 32 (FBXO32) in EC and its regulation by DNMT1-mediated methylation is still unclear. FBXO32 expression was examined in EC cells with high DNMT1 expression using GSE163735 dataset. RT-qPCR assessed FBXO32 expression in normal and EC cells, and impact of higher FBXO32 expression on cell proliferation, migration, and invasion was evaluated, along with EMT-related proteins. The xenograft model established by injecting EC cells transfected with FBXO32 was used to evaluate tumor growth, apoptosis, and tumor cells proliferation and metastasis. Chromatin immunoprecipitation (ChIP) assay was employed to study the interaction between DNMT1 and FBXO32. HitPredict, co-immunoprecipitation (Co-IP), and Glutathione-S-transferase (GST) pulldown assay analyzed the interaction between FBXO32 and cyclin dependent kinase 9 (CDK9). Finally, the ubiquitination assay identified CDK9 ubiquitination, and its half-life was measured using cycloheximide and confirmed through western blotting. DNMT1 negatively correlated with FBXO32 expression in esophageal cells. High FBXO32 expression was associated with better overall survival in patients. Knockdown of DNMT1 in EC cells increased FBXO32 expression and suppressed malignant phenotypes. FBXO32 repressed EC tumor growth and metastasis in mice. Enrichment of DNMT1 in FBXO32 promoter region led to increased DNA methylation and reduced transcription. Mechanistically, FBXO32 degraded CDK9 through promoting its ubiquitination.
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Proliferação de Células , DNA (Citosina-5-)-Metiltransferase 1 , Epigênese Genética , Neoplasias Esofágicas , Proteínas F-Box , Regulação Neoplásica da Expressão Gênica , Camundongos Nus , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/metabolismo , Humanos , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/genética , Animais , Proliferação de Células/genética , Proteínas F-Box/metabolismo , Proteínas F-Box/genética , Linhagem Celular Tumoral , Epigênese Genética/genética , Camundongos , Metilação de DNA/genética , Ubiquitinação , Movimento Celular/genética , Apoptose/genética , Camundongos Endogâmicos BALB C , Sobrevivência Celular/genética , Feminino , MasculinoRESUMO
Background: CD5-positive (CD5+) non-germinal center B-cell-like diffuse large B-cell lymphoma (non-GCB DLBCL) is heterogeneous with a poor prognosis. For refractory DLBCL, the median overall survival was only 6.3 months. Therefore, there is a need for approaches to elongate the survival in this subgroup of relapsed DLBCL patients. Case Description: Here, we present a rare case of a 72-year-old patient with stage IV CD5+ non-GCB DLBCL with myeloid differentiation primary response 88 (MYD88) and cluster of differentiation 79B (CD79B) comutations. Zanubrutinib and rituximab therapy was initially administered until disease progression. Subsequently, zanubrutinib plus rituximab together with attenuated standard chemotherapy (miniCHOP) was applied and a notable response was observed. The patient tolerated the treatment well and exhibited a complete response in lung for about 5 months. Afterwards, the patients experienced relapse in the brain and started programmed death protein 1 (PD-1) regimens of toripalimab plus lenalidomide, which also exhibited a good response with decreased lesions in brain after half-year treatment. However, the patient experienced relapse again in the brain 3 months later and started chemotherapy with methotrexate plus rituximab. The patient had survived for over 2 years since the initial diagnosis of stage IV DLBCL and has continued to survive after experiencing a relapse in the brain for approximately 11 months till now. Conclusions: These findings suggest that toripalimab may be a new therapeutic option for central nervous system recurrence in refractory CD5+ DLBCL with MYD88 and CD79B comutation. Further clinical trials are warranted to confirm these results.
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Responsible for synthesizing the complementary strand of the DNA template, DNA polymerase is a crucial enzyme in DNA replication, recombination and repair. A highly conserved tyrosine (Tyr), located at the C-terminus of the O-helix in family A DNA polymerases, plays a critical role in enzyme activity and fidelity. Here, we combined the technology of genetic code extension to incorporate non-canonical amino acids and molecular dynamics (MD) simulations to uncover the mechanisms by which Tyr671 impacts substrate binding and conformation transitions in a DNA polymerase from Thermus aquaticus. Five non-canonical amino acids, namely l-3,4-dihydroxyphenylalanine (l-DOPA), p-aminophenylalanine (pAF), p-acetylphenylalanine (pAcF), p-cyanophenylalanine (pCNF) and p-nitrophenylalanine (pNTF), were individually incorporated at position 671. Strikingly, Y671pAF and Y671DOPA were active, but with lower activity compared to Y671F and wild-type. Y671pAF showed a higher fidelity than the Y671F, despite both possessing lower fidelity than the wild-type. Metadynamics and long-timescale MD simulations were carried out to probe the role of mutations in affecting protein structure, including open conformation, open-to-closed conformation transition, closed conformation, and closed-to-open conformation transition. The MD simulations clearly revealed that the size of the 671 amino acid residue and interactions with substrate or nearby residues were critical for Tyr671 to determine enzyme activity and fidelity.
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Simulação de Dinâmica Molecular , Taq Polimerase , Tirosina , Tirosina/química , Tirosina/genética , Tirosina/metabolismo , Taq Polimerase/metabolismo , Taq Polimerase/química , Taq Polimerase/genética , Thermus/enzimologia , Thermus/genética , Aminoácidos/química , Aminoácidos/metabolismo , Aminoácidos/genética , Conformação Proteica , Especificidade por Substrato , CinéticaRESUMO
Genes associated with endoplasmic reticulum stress (ERS) and mitophagy can be conducive to predicting solid tumour prognosis. The authors aimed to develop a prognosis prediction model for these genes in lung adenocarcinoma (LUAD). Relevant gene expression and clinical information were collected from public databases including Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA). A total of 265 differentially expressed genes was finally selected (71 up-regulated and 194 downregulated) in the LUAD dataset. Among these, 15 candidate ERS and mitophagy genes (ATG12, CSNK2A1, MAP1LC3A, MAP1LC3B, MFN2, PGAM5, PINK1, RPS27A, SQSTM1, SRC, UBA52, UBB, UBC, ULK1, and VDAC1) might be critical to LUAD based on the expression analysis after crossing with the ERS and mitochondrial autophagy genes. The prediction model demonstrated the ability to effectively predict the 5-, 3-, and 1-year prognoses of LUAD patients in both GEO and TCGA databases. Moreover, high VDAC1 expression was associated with poor overall survival in LUAD (p < 0.001), suggesting it might be a critical gene for LUAD prognosis prediction. Overall, the prognosis model based on ERS and mitophagy genes in LUAD can be useful for evaluating the prognosis of patients with LUAD, and VDAC1 may serve as a promising biomarker for LUAD prognosis.
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Adenocarcinoma de Pulmão , Estresse do Retículo Endoplasmático , Neoplasias Pulmonares , Mitofagia , Humanos , Mitofagia/genética , Estresse do Retículo Endoplasmático/genética , Prognóstico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Canal de Ânion 1 Dependente de Voltagem/genética , Canal de Ânion 1 Dependente de Voltagem/metabolismo , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Perfilação da Expressão Gênica , TranscriptomaRESUMO
Tyrosinase (TYR) is an essential oxidase that is responsible for the regulation of multiple physiological processes and diseases. Achieving the trace and reliable detection of TYR in complex biological samples is of great significance for the diagnosis of TYR-related diseases, but which faces a great challenge. In this study, we developed an ingenious and powerful method for the ultrasensitive detection of TYR by click reaction-combined dark-field microscopy. This method begins with the formation of cuprous ions (Cu+) based on the reduction of copper ions (Cu2+) by ascorbic acid (AA). Subsequently, the formed Cu+ can catalyze the crosslinking between azide- and alkyne-functionalized gold nanoparticles, causing a significant red-shift in the scattering spectrum. However, AA can chelate with TYR, which inhibits the generation of Cu+ and subsequent click reaction, thus achieving TYR-controlled scattering spectral shift. The proposed sensing platform shows a good linear detection range of 0.01-0.8 U/L with a low detection limit of 0.003 U/L, which is three orders of magnitude lower than the best performance of TYR sensing probes reported to date. Most importantly, the strategy has the ability to reliably and accurately detect TYR in serum sample, suggesting its potential clinical application in diagnosing TYR-related diseases. This visual sensing platform offers promising prospects for future research in enzymatic analysis and biomedical diagnostics.
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Técnicas Biossensoriais , Nanopartículas Metálicas , Monofenol Mono-Oxigenase , Cobre/análise , Ouro , Técnicas Biossensoriais/métodos , Ácido Ascórbico , Íons , Química Click/métodosRESUMO
Bicyclo[1.1.1]pentane (BCP) heteroaryls make up an important class of BCP derivatives in drug discovery. Herein, we report the visible-light-mediated synthesis of cyanoisopropyl BCP-heteroaryls motifs from N-containing heterocycles, [1.1.1]propellane, and AIBN (2,2'-azobis(isobutyronitrile)) through three-component cascade reaction. Importantly, this protocol is compatible with pyrazinones, quinoxaline-2(1H)-one, azauracils, quinoline derivatives, and imidazo[1,2-b]pyridazine, as well as various phenyl disulfide derivatives; thus, this operationally simple and general methodology could enable rapid library generation of sought-after BCP derivatives for drug development.
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The Pseudomonas aeruginosa lipase PaL catalyzes the stereoselective hydrolysis of menthyl propionate to produce L-menthol. The lack of a three-dimensional structure of PaL has so far prevented a detailed understanding of its stereoselective reaction mechanism. Here, the crystal structure of PaL was determined at a resolution of 1.80 Å by single-wavelength anomalous diffraction. In the apo-PaL structure, the catalytic His302 is located in a long loop on the surface that is solvent exposed. His302 is distant from the other two catalytic residues, Asp274 and Ser164. This configuration of catalytic residues is unusual for lipases. Using metadynamics simulations, we observed that the enzyme undergoes a significant conformational change upon ligand binding. We also explored the catalytic and stereoselectivity mechanisms of PaL by all-atom molecular dynamics simulations. These findings could guide the engineering of PaL with an improved diastereoselectivity for L-menthol production.
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Developing advanced electrolytes has been regarded as a pivotal strategy for enhancing the electrochemical performance of batteries; however, the criteria for electrolyte design remain elusive. In this study, we present an electrolyte design chart reframed through intermolecular interactions. By combining systematic nuclear magnetic resonance, Fourier transform infrared measurements, molecular dynamics (MD) simulations, and machine-learning-assisted classifications, we establish semiquantitative correlations between electrolyte components and the electrochemical reversibility of electrolytes. We propose the equivalent increment of Li salt resulting from functional cosolvent and solvent-solvent interactions for effective electrolyte design and prediction. The controllable regulation of the electrolyte design chart by the properties of solvent-solvent interactions presents varying equivalent effects of increasing Li salt concentrations in different electrolyte systems. Based on this mechanism, we demonstrate highly reversible and nonflammable phosphate-based electrolytes for graphite||NCM811 full cells. The proposed electrolyte design chart, semiquantitatively determined by intermolecular interactions, provides the necessary experimental foundation and basis for the future rapid screening and prediction of electrolytes using machine-learning methods.
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Nanoengineering polar oxide films have attracted great attention in energy storage due to their high energy density. However, most of them are deposited on thick and rigid substrates, which is not conducive to the integration of capacitors and applications in flexible electronics. Here, an alternative strategy using van der Waals epitaxial oxide dielectrics on ultra-thin flexible mica substrates is developed and increased the disorder within the system through high laser flux. The introduction of defects can efficiently weaken or destroy the long-range ferroelectric ordering, ultimately leading to the emergence of a large numbers of weak-coupling regions. Such polarization configuration ensures fast polarization response and significantly improves energy storage characteristics. A flexible BiFeO3-BaTiO3 (BF-BT) capacitor exhibits a total energy density of 43.5 J cm-3 and an efficiency of 66.7% and maintains good energy storage performance over a wide temperature range (20-200 °C) and under large bending deformation (bending radii ≈ 2 mm). This study provides a feasible approach to improve the energy storage characteristics of dielectric oxide films and paves the way for their practical application in high-energy density capacitors.
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Ribonucleic acids (RNA) play active roles within cells or viruses by catalyzing biological reactions, controlling gene expression, and communicating responses to cellular signals. Rapid monitoring RNA variation has become extremely important for appropriate clinical decisions and frontier biological research. However, the most widely used method for RNA detection, nucleic acid amplification, is restricted by a mandatory temperature cycling period of ≈1 h required to reach target detection criteria. Herein, a direct detection approach via single-atom site integrated surface-enhanced Raman scattering (SERS) monitoring nucleic acid pairing reaction, can be completed within 3 min and reaches high sensitivity and extreme reproducibility for COVID-19 and two other influenza viruses' detection. The mechanism is that a single-atom site on SERS chip, enabled by positioning a single-atom oxide coordinated with a specific complementary RNA probe on chip nanostructure hotspots, can effectively bind target RNA analytes to enrich them at designed sites so that the binding reaction can be detected through Raman signal variation. This ultrafast, sensitive, and reproducible single-atom site SERS chip approach paves the route for an alternative technique of immediate RNA detection. Moreover, single-atom site SERS is a novel surface enrichment strategy for SERS active sites for other analytes at ultralow concentrations.
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Nanopartículas Metálicas , Ácidos Nucleicos , Reprodutibilidade dos Testes , Limite de Detecção , Nanopartículas Metálicas/química , RNA , Análise Espectral Raman/métodos , Ouro/químicaRESUMO
Introduction: Adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) are considered pre-invasive forms of lung adenocarcinoma (LUAD) with a 5-year recurrence-free survival of 100%. We investigated genomic profiles in early tumorigenesis and distinguished mutational features of preinvasive to invasive adenocarcinoma (IAC) for early diagnosis. Methods: Molecular information was obtained from a 689-gene panel in the 90 early-stage LUAD Chinese patients using next-generation sequencing. Gene signatures were identified between pathology subtypes, including AIS/MIA (n=31) and IAC (n=59) in this cohort. Mutational and clinicopathological information was also obtained from the Cancer Genome Atlas (TCGA) as a comparison cohort. Results: A higher mutation frequency of TP53, RBM10, MUC1, CSMD, MED1, LRP1B, GLI1, MAP3K, and RYR2 was observed in the IAC than in the AIS/MIA group. The AIS/MIA group showed higher mutation frequencies of ERBB2, BRAF, GRIN2A, and RB1. Comparable mutation rates for mutually exclusive genes (EGFR and KRAS) across cohorts highlight the critical transition to invasive LUAD. Compared with the TCGA cohort, EGFR, KRAS, TP53, and RBM10 were frequently mutated in both cohorts. Despite limited gene mutation overlap between cohorts, we observed variant mutation types in invasive LUAD. Additionally, the tumor mutation burden (TMB) values were significantly lower in the AIS/MIA group than in the IAC group in both the Chinese cohort (P=0.0053) and TCGA cohort (P<0.01). Conclusion: These findings highlight the importance of distinguishing preinvasive from invasive LUAD in the early stages of LUAD and both pathology and molecular features in clinical practice, revealing genomic tumor heterogeneity and population differences.