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The phase transition in layered MoS2 has attracted wide attention but the detailed phase transition process is still unclear. Here, the H â T' phase transition mechanism of single- and bilayer MoS2 induced by lithium intercalation has been systematically studied using first principles. The results indicated that the lithium intercalation can effectively reduce the sliding barrier of the S atom layer. Moreover, we demonstrated that the phase transition process in bilayer MoS2 is induced by S atom transition one by one instead of the collective behavior of the S atoms. Importantly, we found that the phase transition process in bilayer MoS2 consists of the formation, diffusion and recombination of S vacancies, and the phase transition originates from interlayer lithium defects. In addition, the lithium defects cannot induce phase transition in monolayer MoS2 due to the larger sliding barrier of the S atom.
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Evodia rutaecarpa (E. rutaecarpa) has been used to treat aches, vomiting and dysentery in traditional Chinese medicine. However, as a mildly toxic herb its toxic components have not been elucidated. An attempt was made to illuminate the hepatotoxic constituents of E. rutaecarpa. The 50% ethanol extracts of E. rutaecarpa from 19 different sources were used to establish UPLC fingerprints and administered to mice at a dose of 35 g/kg (crude medicine weight/mouse weight) once daily for 14 days. Serum levels of alanine transaminase, aspartate aminotransferase and liver coefficient were used as indices of liver injury. Additionally, the characteristic peaks of 19 fingerprints were identified. Spectrum-effect relationships between fingerprints and hepatotoxic indicators were analyzed using bivariate correlation analysis (BCA). The UPLC fingerprints were established and a total of 28 main compounds were identified. Because of the inherent variations in chemical compositions, the liver injury levels were different among the E. rutaecarpa samples from 19 sites of production. BCA results indicated that compounds dihydrorutaecarpine, 6-acetoxy-5-epilimonin, goshuyuamide I, 1-methyl-2-[(Z)-5-undecenyl]-4(1H)-quinolone, 1-methyl-2-[(4Z,7Z)-4,7-tridecadienyl]-4(1H)-quinolone, evocarpine and 1-methyl-2-[(6Z,9Z)-6,9-pentadecadienyl]-4(1H)-quinolone were tentatively determined as the primary hepatotoxic components. The present study provides a valuable method for the discovery of hepatotoxic constituents by combination of fingerprints and hepatotoxicity index.
Assuntos
Cromatografia Líquida/métodos , Evodia/química , Fígado/efeitos dos fármacos , Espectrometria de Massas/métodos , Extratos Vegetais/análise , Extratos Vegetais/toxicidade , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Feminino , Masculino , Camundongos , Análise de Componente PrincipalRESUMO
MAIN CONCLUSION: Nine CAD/CAD-like genes in P. tomentosa were classified into four classes based on expression patterns, phylogenetic analysis and biochemical properties with modification for the previous claim of SAD. Cinnamyl alcohol dehydrogenase (CAD) functions in monolignol biosynthesis and plays a critical role in wood development and defense. In this study, we isolated and cloned nine CAD/CAD-like genes in the Populus tomentosa genome. We investigated differential expression using microarray chips and found that PtoCAD1 was highly expressed in bud, root and vascular tissues (xylem and phloem) with the greatest expression in the root. Differential expression in tissues was demonstrated for PtoCAD3, PtoCAD6 and PtoCAD9. Biochemical analysis of purified PtoCADs in vitro indicated PtoCAD1, PtoCAD2 and PtoCAD8 had detectable activity against both coniferaldehyde and sinapaldehyde. PtoCAD1 used both substrates with high efficiency. PtoCAD2 showed no specific requirement for sinapaldehyde in spite of its high identity with so-called PtrSAD (sinapyl alcohol dehydrogenase). In addition, the enzymatic activity of PtoCAD1 and PtoCAD2 was affected by temperature. We classified these nine CAD/CAD-like genes into four classes: class I included PtoCAD1, which was a bone fide CAD with the highest activity; class II included PtoCAD2, -5, -7, -8, which might function in monolignol biosynthesis and defense; class III genes included PtoCAD3, -6, -9, which have a distinct expression pattern; class IV included PtoCAD12, which has a distinct structure. These data suggest divergence of the PtoCADs and its homologs, related to their functions. We propose genes in class II are a subset of CAD genes that evolved before angiosperms appeared. These results suggest CAD/CAD-like genes in classes I and II play a role in monolignol biosynthesis and contribute to our knowledge of lignin biosynthesis in P. tomentosa.
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Oxirredutases do Álcool/genética , Família Multigênica , Proteínas de Plantas/genética , Populus/genética , Oxirredutases do Álcool/classificação , Oxirredutases do Álcool/metabolismo , Sequência de Aminoácidos , Clonagem Molecular , Perfilação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Concentração de Íons de Hidrogênio , Isoenzimas/genética , Isoenzimas/metabolismo , Cinética , Lignina/metabolismo , Meristema/enzimologia , Meristema/genética , Modelos Moleculares , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Feixe Vascular de Plantas/enzimologia , Feixe Vascular de Plantas/genética , Populus/enzimologia , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , TemperaturaRESUMO
BACKGROUND AND OBJECTIVE: Grading the severity level is an extremely important procedure for correct diagnoses and personalized treatment schemes for acne. However, the acne grading criteria are not unified in the medical field. This work aims to develop an acne diagnosis system that can be generalized to various criteria. METHODS: A unified acne grading framework that can be generalized to apply referring to different grading criteria is developed. It imitates the global estimation of the dermatologist diagnosis in two steps. First, an adaptive image preprocessing method effectively filters meaningless information and enhances key information. Next, an innovative network structure fuses global deep features with local features to simulate the dermatologists' comparison of local skin and global observation. In addition, a transfer fine-tuning strategy is proposed to transfer prior knowledge on one criterion to another criterion, which effectively improves the framework performance in case of insufficient data. RESULTS: The Preprocessing method effectively filters meaningless areas and improves the performance of downstream models.The framework reaches accuracies of 84.52% and 59.35% on two datasets separately. CONCLUSIONS: The application of the framework on acne grading exceeds the state-of-the-art method by 1.71%, reaches the diagnostic level of a professional dermatologist and the transfer fine-tuning strategy improves the accuracy of 6.5% on the small data.
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Acne Vulgar , Acne Vulgar/diagnóstico por imagem , Coleta de Dados , Humanos , Projetos de Pesquisa , Pele/diagnóstico por imagemRESUMO
While the androgen receptor (AR) may influence the progression of clear cell renal cell carcinoma (ccRCC), its role to impact vasculogenic mimicry (VM) to alter the ccRCC progression and metastasis remains obscure. Here, we demonstrated that elevated AR expression was positively correlated with tumor-originated vasculogenesis in ccRCC patients. Consistently, in vitro research revealed AR promoted VM formation in ccRCC cell lines via modulating lncRNA-TANAR/TWIST1 signals. Mechanism dissection showed that AR could increase lncRNA-TANAR (TANAR) expression through binding to the androgen response elements (AREs) located in its promoter region. Moreover, we found that TANAR could impede nonsense-mediated mRNA decay (NMD) of TWIST1 mRNA by direct interaction with TWIST1 5'UTR. A preclinical study using in vivo mouse model with orthotopic xenografts of ccRCC cells further confirmed the in vitro data. Together, these results illustrated that AR-mediated TANAR signals might play a crucial role in ccRCC VM formation and metastasis, and targeting this newly identified AR/TANAR/TWIST1 signaling may help in the development of a novel anti-angiogenesis therapy to better suppress the ccRCC progression.
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Carcinoma de Células Renais/genética , Neovascularização Patológica/genética , Proteínas Nucleares/genética , RNA Longo não Codificante/genética , Receptores Androgênicos/genética , Proteína 1 Relacionada a Twist/genética , Animais , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Códon sem Sentido/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Neovascularização Patológica/patologia , Degradação do RNAm Mediada por Códon sem Sentido/genética , Transdução de Sinais/genéticaRESUMO
Caspase recruitment domain family member 8 (CARD8) is an adaptor molecule that negatively regulates nuclear factor-κB (NF-κB) activation, interleukin (IL)-1ß secretion, and apoptosis. These play important roles in the pathogenesis of psoriasis. Genetic variants of CARD8 have been associated with an increased risk of several inflammatory diseases and psoriasis in Europe. However, nothing is known about the association of the polymorphisms of CARD8 and psoriasis vulgaris (PsV) in the Han population of northeastern China. To investigate the potential association between them, we designed a case-control study to genotype four selected single nucleotide polymorphisms (SNPs) using the improved multiplex ligation reaction (iMLDR) method. Model-based single SNP frequentist-test and haplotype association studies were performed to assess the association between SNPs and PsV. The results showed that the intron SNP rs10403848 was significantly associated with PsV (additive model p=0.0418, p'=0.0411, and statistical power 0.1902; heterozygous model p=0.0418, p'=0.0164, and statistical power 0.9406). A potential risk locus of nonsynonymous SNP rs2043211 found in the European population did not show a significant association in our study. We found that the polymorphism rs10403848 in CARD8 is significantly associated with PsV risk in the Han population of northeastern China. CARD8 may be involved in PsV in this population, as in the European population, but a different genetic process should be considered for the heterogeneity of risk loci.