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Due to their fascinating topological structures and application prospects, coordination supramolecular complexes have continuously been studied by scientists. However, the controlled construction and property study of organometallic handcuffs remains a significant and challenging research subject in the area of supramolecular chemistry. Hence, a series of tetranuclear organometallic and heterometallic handcuffs bearing different size and metal types were rationally designed and successfully synthesized by utilizing a quadridentate pyridyl ligand (tetra-(3-pyridylphenyl)ethylene) based on three Cp*Rh (Cp* = η5-C5Me5) fragments bearing specific longitudinal dimensions and conjugated planes. These results were determined with single-crystal X-ray diffraction analysis technology, ESI-MS NMR spectroscopy, etc. Importantly, the photoquenching effect of Cp* groups and the discrepancy of intermolecular π-π stacking interactions between building block and half-sandwich fragments promote markedly different photothermal conversion results. These results will further push the synthesis of topological structures and the development of photothermal conversion materials.
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Carbohydrate-based drug discovery has gained more and more attention during the last few decades. Resin glycoside is a kind of novel and complex glycolipids mainly distributed in plants of the family Convolvulaceae. Over the last decade, a number of natural resin glycosides and derivatives have been isolated and identified, and exhibited a broad spectrum of biological activities, such as cytotoxic, multidrug-resistant reversal on both microbial pathogens and mammalian cancer cells, antivirus, anticonvulsant, antidepressant, sedative, vasorelaxant, laxative, and α-glucosidase inhibitory effects, indicating their potential as lead compounds for drug discovery. A systematic review of the literature studies was carried out to summarize the chemistry and biological activity of resin glycosides from Convolvulaceae species, based on various data sources such as PubMed, Web of Science, Scopus, and Google scholar. The keyword "Convolvulaceae" was paired with "resin glycoside," "glycosidic acid," "glycolipid," or "oligosaccharide," and the references published between 2009 and June 2021 were covered. In this article, we comprehensively reviewed the structures of 288 natural resin glycoside and derivatives newly reported in the last decade. Moreover, we summarized the biological activities and mechanisms of action of the resin glycosides with pharmaceutical potential. Taken together, great progress has been made on the chemistry and biological activity of resin glycosides from Convolvulaceae species, however, more exploratory research is still needed, especially on the mechanism of action of the biological activities.
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Convolvulaceae , Animais , Anticonvulsivantes , Convolvulaceae/química , Glicolipídeos , Glicosídeos/química , Glicosídeos/farmacologia , Humanos , Hipnóticos e Sedativos , Laxantes , Mamíferos , Oligossacarídeos , Preparações Farmacêuticas , Resinas Vegetais/química , Resinas Vegetais/farmacologia , Vasodilatadores , alfa-GlucosidasesRESUMO
BACKGROUND: Erythromycin A (Er A) has a broad antibacterial effect and is a source of erythromycin derivatives. Methylation of erythromycin C (Er C), catalyzed by S-adenosyl-methionine (SAM)-dependent O-methyltransferase EryG, is the key final step in Er A biosynthesis. Er A biosynthesis, including EryG production, is regulated by the phosphate response factor PhoP and the nitrogen response factor GlnR. However, the regulatory effect of these proteins upon S-adenosyl-methionine synthetase (MetK) production is unknown. RESULTS: In this study, we used bioinformatics approaches to identify metK (SACE_3900), which codes for S-adenosyl-methionine synthetase (MetK). Electrophoretic mobility shift assays (EMSAs) revealed that PhoP and GlnR directly interact with the promoter of metK, and quantitative PCR (RT-qPCR) confirmed that each protein positively regulated metK transcription. Moreover, intracellular SAM was increased upon overexpression of either phoP or glnR under phosphate or nitrogen limited conditions, respectively. Finally, both the production of Er A and the transformation ratio from Er C to Er A increased upon phoP overexpression, but surprisingly, not upon glnR overexpression. CONCLUSIONS: Manipulating the phosphate and nitrogen response factors, PhoP and GlnR provides a novel strategy for increasing the yield of SAM and the production of Er A in Saccharopolyspora erythraea .
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Saccharopolyspora , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Eritromicina , Regulação Bacteriana da Expressão Gênica , Metionina/metabolismo , Nitrogênio/metabolismo , Fosfatos/metabolismo , S-Adenosilmetionina/metabolismo , Saccharopolyspora/genética , Saccharopolyspora/metabolismoRESUMO
The longevity phenomenon is entirely controlled by the insulin signaling pathway (IIS-pathway). Both vertebrates and invertebrates have IIS-pathways that are comparable to one another, though no one has previously described de novo transcriptome assembly of IIS-pathway-associated genes in termites. In this research, we analyzed the transcriptomes of both reproductive (primary kings "PK" and queens "PQ", secondary worker reproductive kings "SWRK" and queens "SWRQ") and non-reproductive (male "WM" and female "WF" workers) castes of the subterranean termite Reticulitermes chinensis. The goal was to identify the genes responsible for longevity in the reproductive and non-reproductive castes. Through transcriptome analysis, we annotated 103,589,264 sequence reads and 184,436 (7G) unigenes were assembled, GC performance was measured at 43.02%, and 64,046 sequences were reported as CDs sequences. Of which 35 IIS-pathway-associated genes were identified, among 35 genes, we focused on the phosphoinositide-dependent kinase-1 (Pdk1), protein kinase B2 (akt2-a), tuberous sclerosis-2 (Tsc2), mammalian target of rapamycin (mTOR), eukaryotic translation initiation factor 4E (EIF4E) and ribosomal protein S6 (RPS6) genes. Previously these genes (Pdk1, akt2-a, mTOR, EIF4E, and RPS6) were investigated in various organisms, that regulate physiological effects, growth factors, protein translation, cell survival, proliferation, protein synthesis, cell metabolism and survival, autophagy, fecundity rate, egg size, and follicle number, although the critical reason for longevity is still unclear in the termite castes. However, based on transcriptome profiling, the IIS-pathway-associated genes could prolong the reproductive caste lifespan and health span. Therefore, the transcriptomic shreds of evidence related to IIS-pathway genes provide new insights into the maintenance and relationships between biomolecular homeostasis and remarkable longevity. Finally, we propose a strategy for future research to decrypt the hidden costs associated with termite aging in reproductive and non-reproductive castes.
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Isópteros , Animais , Feminino , Masculino , Fator de Iniciação 4E em Eucariotos/genética , Insulina/metabolismo , Isópteros/genética , Isópteros/metabolismo , Longevidade/genética , Serina-Treonina Quinases TOR/metabolismo , TranscriptomaRESUMO
Natural products are a source for pesticide or drug discovery. In order to discover lead compounds with high fungicidal or herbicidal activity, new niacinamide derivatives derived from the natural product niacinamide, containing chiral flexible chains, were designed and synthesized. Their structures were confirmed by 1H NMR, 13C NMR and HRMS analysis. The fungicidal and herbicidal activities of these compounds were tested. The fungicidal activity results demonstrated that the compound (S)-2-(2-chloronicotinamido)propyl-2-methylbenzoate (3i) exhibited good fungicidal activity (92.3% inhibition) against the plant pathogen Botryosphaeria berengriana at 50 µg/mL and with an EC50 of 6.68 ± 0.72 µg/mL, which is the same as the positive control (fluxapyroxad). Compound 3i was not phytotoxic and could therefore be used as a fungicide on crops. Structure-activity relationships (SAR) were studied by molecular docking simulations with the succinate dehydrogenase of the fungal mitochondrial respiratory chain.
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Fungicidas Industriais , Herbicidas , Praguicidas , Praguicidas/farmacologia , Niacinamida/farmacologia , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Fungicidas Industriais/química , Herbicidas/farmacologia , Estrutura MolecularRESUMO
Objective To clarify the hotspots and trends of multimorbidity research and to provide evidence for further research in China. Methods Papers on multimorbidity were retrieved from PubMed and Web of Science (from inception to August 11,2021).BICOMB and gCLUTO were used for bibliometric and clustering analysis,and CiteSpace was employed for analysis of authors and citations,and burst detection of keywords. Results The research on multimorbidity has been on the rise.Among the authors,Mercer SW published the most papers on this topic and Fortin M was the most cited author.Karolinska Institute topped the institutions in the number of published papers,and the paper published in Lancet by Barnett K in 2012 was the most cited.A total of 75 high-frequency keywords were extracted,on the basis of which seven research hotspots were summarized:epidemiology (including the prevalence and trend),medication (involving polypharmacy,medication compliance,etc.),medical expenditure (including cost and medical services),aging (such as elderly patients,frailty,and disability),psychology (involving mental health,social support,etc.),multimorbidity management (such as the treatment,primary health care,and integrated care),and comorbidity of cardiovascular and metabolic diseases (involving obesity,stroke,diabetes,etc.). Conclusions Multimorbidity is concerned as a major health threat and public health problem worldwide.The management of multimorbidity is more complex than that of one disease,which thus faces more challenges.Therefore,researchers,health care providers,and policy-makers should underscore it.
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Bibliometria , Multimorbidade , Idoso , China/epidemiologia , Comorbidade , HumanosRESUMO
An open-frame aluminophosphate, K[(Zn0.5Al0.5)2P2O8] (KZAPO), was rationally designed by a substitution design strategy and synthesized by a high-temperature molten salt method. Compared with the parent crystal of K[ZnBP2O8], KZAPO was characterized by similar 4 × 8 × 8 networks, a comparable short-wave ultraviolet transparency and a more regular tetrahedral frame with the mixing of (ZnO4)6- and (AlO4)5- anionic groups, highlighting the multifunctional roles that anionic group mixing played in structural and property modulations. In particular, KZAPO was characterized by a high thermal stability (over 850 °C) and a congruent-melting behavior, being conducive to practical applications.
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BACKGROUND: In this study, we explored whether the proposed short-echo-time magnitude (setMag) image derived from quantitative susceptibility mapping (QSM) could resemble NM-MRI image in substantia nigra (SN), by quantitatively comparing the spatial similarity and diagnosis performances for Parkinson's disease (PD). METHODS: QSM and NM-MRI were performed in 18 PD patients and 15 healthy controls (HCs). The setMag images were calculated using the short-echo-time magnitude images. Bilateral hyperintensity areas of SN (SNhyper) were manually segmented on setMag and NM-MRI images by two raters in a blinded manner. The inter-rater reliability was evaluated by the intraclass correlation coefficients (ICC) and the Dice similarity coefficient (DSC). Then the inter-modality (i.e. setMag and NM-MRI) spatial similarity was quantitatively assessed using DSC and volume of the consensual voxels identified by both of two raters. The performances of mean SNhyper volume for PD diagnosis on setMag and NM-MRI images were evaluated using receiver operating characteristic (ROC) analysis. RESULTS: The SNhyper segmented by two raters showed substantial to excellent inter-rater reliability for both setMag and NM-MRI images. The DSCs of SNhyper between setMag and NM-MRI images showed substantial to excellent voxel-wise overlap in HCs (0.80 ~ 0.83) and PD (0.73 ~ 0.76), and no significant difference was found between the SNhyper volumes of setMag and NM-MRI images in either HCs or PD (p > 0.05). The mean SNhyper volume was significantly decreased in PD patients in comparison with HCs on both setMag images (77.61 mm3 vs 95.99 mm3, p < 0.0001) and NM-MRI images (79.06 mm3 vs 96.00 mm3, p < 0.0001). Areas under the curve (AUCs) of mean SNhyper volume for PD diagnosis were 0.904 on setMag and 0.906 on NM-MRI images. No significant difference was found between the two curves (p = 0.96). CONCLUSIONS: SNhyper on setMag derived from QSM demonstrated substantial spatial overlap with that on NM-MRI and provided comparable PD diagnostic performance, providing a new QSM-based multi-contrast imaging strategy for future PD studies.
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Interpretação de Imagem Assistida por Computador/métodos , Melaninas/análise , Doença de Parkinson/diagnóstico por imagem , Substância Negra/diagnóstico por imagem , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos TestesRESUMO
Phosphate concentration extensively modulates the central physiological processes mediated by the two-component system PhoR-PhoP in actinobacteria. The system serves a role beyond phosphate metabolism, mediating crucial functions in nitrogen and carbon metabolism, and secondary metabolism in response to the nutritional states. Here, we found that the phosphate-sensing regulator PhoP was propionylated, and thus lost its DNA-binding activity in vivo and in vitro in Saccharopolyspora erythraea. Two key conserved lysine residues 198 and 203 (K198 and K203) in winged HTH motif at the C-terminal domain of PhoP are propionylated by protein acyltransferase AcuA (encoding by sace_5148). Single amino acid mutation of these two lysine residues resulted in severely impaired binding of PhoP to PHO box. The addition of propionate (to supply precursors for erythromycin biosynthesis) increases the intracellular propionylation level of PhoP, resulting in the loss of response to phosphate availability. Furthermore, simultaneous mutation of K198 and K203 of PhoP to arginine, mimicking the non-propionylated form, promotes the expression of the PhoP regulon under the condition of propionate addition. Together, these findings present a common regulatory mechanism of genes' expression mediated by posttranslational regulation of OmpR family transcriptional regulator PhoP and provide new insights into the multifaceted regulation of metabolism in response to nutritional signals.
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Acetiltransferases/metabolismo , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica/genética , Saccharopolyspora/genética , Transcrição Gênica/genética , Substituição de Aminoácidos/genética , Sítios de Ligação/genética , Proteínas de Ligação a DNA/metabolismo , Lisina/metabolismo , Fosfatos/metabolismo , Transativadores/genética , Transativadores/metabolismo , Ativação TranscricionalRESUMO
Anthranilic diamide insecticide could control lepidopteran pests by selectively binding and activating insect ryanodine receptors (RyRs), and the unique mode of action is different from other conventional insecticides. In order to discover new anthranilic diamide insecticide as ryanodine receptors activators, a series of 11 novel anthranilic diamides derivatives (Ia-k) were synthesized and confirmed by melting point, 1H NMR, 13C NMR and elemental analyses. The preliminary bioactivity revealed that most title compounds showed moderate to remarkable activities against oriental armyworm (Mythimna separata) and diamondback moth (Plutella xylostella). Especially, compounds Ia and If, which exhibited 100% larvicidal activity against oriental armyworm at 1.0â¯mgâ¯L-1, and comparable to that of chlorantraniliprole (100% at 1â¯mgâ¯L-1). If displayed 60% insecticidal activity against diamondback moth at 0.01â¯mgâ¯L-1, better than chlorantraniliprole (45% at 0.01â¯mgâ¯L-1). The preliminary structure activity relationships were discussed. In addition, the calcium imaging experiment indicated that the insect ryanodine receptor is the potential target of If.
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Amidas/farmacologia , Agonistas dos Canais de Cálcio/farmacologia , Inseticidas/farmacologia , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , ortoaminobenzoatos/farmacologia , Amidas/síntese química , Amidas/química , Animais , Cálcio/metabolismo , Agonistas dos Canais de Cálcio/síntese química , Agonistas dos Canais de Cálcio/química , Inseticidas/síntese química , Inseticidas/química , Larva/efeitos dos fármacos , Estrutura Molecular , Mariposas/efeitos dos fármacos , Periplaneta/efeitos dos fármacos , Relação Estrutura-Atividade , Sulfonas/síntese química , Sulfonas/química , Sulfonas/farmacologia , ortoaminobenzoatos/síntese química , ortoaminobenzoatos/químicaRESUMO
A series of isomorphic lanthanide metal-organic frameworks (Ln-MOFs), namely [Ln(dcbba)(DMF)2] n·H2O·0.5DMF [Ln = La (1), Eu (2) and Tb (3); H3dcbba = 4-(3, 5-dicarboxylatobenzyloxy)benzoic acid; DMF = N, N'-dimethylformamide] have been designed and synthesized by the solvothermal reactions of H3dcbba and La(NO3)3·6H2O. Single-crystal X-ray diffraction analysis reveals that the complexes 1-3 exhibit a (3,6)-connected open framework structure with binuclear [Ln2(COO)6] n secondary building units as 6-connected nodes and H3dcbba ligands as 3-connected nodes. The isostructural mixed La/Eu/Tb-dcbba (4) was obtained via the in-suit doping of different Ln3+ ions into the host framework, which is able to emit pure orange, white, and blue light when excited at 300, 305, and 350 nm, respectively. Subsequently, a novel and multifunctional sensing process was designed based on the excitation wavelength sensitive color tunable luminescent sample 4, which can detect HS- ions, THF (tetrahydrofuran), and Ag+ ions via different luminescence color change mechanisms. The remarkable color change, excellent selectivity, and high sensitivity further indicate the promise of this type of multifunctional luminescent materials for the sensing of anion, cation, and organic small molecule.
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TSP50, a testis-specific gene encoding a serine protease-like protein, was specifically expressed in the spermatocytes of testes but abnormally activated and expressed in many different kinds of cancers. Here, we aimed to analyze the expression of TSP50 in mouse embryo and its function in early embryonic development. Firstly, the distribution of TSP50 in oocytes and embryonic development was characterized by immunofluorescence, RT-PCR and western blotting, and the results showed that TSP50 was detected at all studied stages with a dynamic expression pattern. When overexpressed TSP50 in zygotes by microinjection, the zygotes development was highly accelerated. On the contrary, knocking down TSP50 expression by RNA interference greatly retarded the zygote development. Furthermore, TSP50 expression at embryonic day 6.5 (E6.5), day 8.5 (E8.5) and day 10.5 (E10.5) were increasingly enhanced, However, the expression of TSP50 decreased gradually in the development and differentiation of cardiac myocyte from E12.5 to postnatal (P0). Additionally, we found that TSP50 expression was decreased during cardiac myocyte differentiation of P19 cells. Overexpression of TSP50 could decrease the expression of GATA-4, and knockdown of TSP50 markedly increase the expression of GATA-4. Taken together, our data indicate that TSP50 may play an important role during the process of mouse embryonic development as well as myocardial cell differentiation.
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Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/enzimologia , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Animais , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/fisiologia , Feminino , Coração Fetal/embriologia , Coração Fetal/enzimologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Técnicas de Silenciamento de Genes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , GravidezRESUMO
We developed a high-throughput mass spectrometry method, pLink-SS (http://pfind.ict.ac.cn/software/pLink/2014/pLink-SS.html), for precise identification of disulfide-linked peptides. Using pLink-SS, we mapped all native disulfide bonds of a monoclonal antibody and ten standard proteins. We performed disulfide proteome analyses and identified 199 disulfide bonds in Escherichia coli and 568 in proteins secreted by human endothelial cells. We discovered many regulatory disulfide bonds involving catalytic or metal-binding cysteine residues.
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Dissulfetos/química , Espectrometria de Massas , Proteoma/química , Proteômica/métodos , Sequência de Aminoácidos , Escherichia coli/química , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Biblioteca de Peptídeos , Ribonucleases/químicaRESUMO
BACKGROUND: Diffusion kurtosis imaging (DKI) has the potential to provide microstructural insights into myelin and axonal pathology with additional kurtosis parameters. To our knowledge, few studies are available in the current literature using DKI by tract-based spatial statistics (TBSS) analysis in patients with multiple sclerosis (MS). The aim of this study is to assess the performance of commonly used parameters derived from DKI and diffusion tensor imaging (DTI) in detecting microstructural changes and associated pathology in relapsing remitting MS (RRMS). METHODS: Thirty-six patients with RRMS and 49 age and sex matched healthy controls underwent DKI. The brain tissue integrity was assessed by fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (Da), radial diffusivity (Dr), mean kurtosis (MK), axial kurtosis (Ka) and radial kurtosis (Kr) of DKI and FA, MD, Da and Dr of DTI. Group differences in these parameters were compared using TBSS (P < 0.01, corrected). To compare the sensitivity of these parameters in detecting white matter (WM) damage, the percentage of the abnormal voxels based on TBSS analysis, relative to the whole skeleton voxels for each parameter was calculated. RESULTS: The sensitivities in detecting WM abnormality in RRMS were MK (78.2%) > Kr (76.7%) > Ka (53.5%) and Dr (78.8%) > MD (76.7%) > FA (74.1%) > Da (28.3%) for DKI, and Dr (79.8%) > MD (79.5%) > FA (68.6%) > Da (40.1%) for DTI. DKI-derived diffusion parameters (FA, MD, and Dr) were sensitive for detecting abnormality in WM regions with coherent fiber arrangement; however, the kurtosis parameters (MK and Kr) were sensitive to discern abnormalities in WM regions with complex fiber arrangement. CONCLUSIONS: The diffusion and kurtosis parameters could provide complementary information for revealing brain microstructural damage in RRMS. Dr and DKI_Kr may be regarded as useful surrogate markers for reflecting pathological changes in RRMS.
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Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Anisotropia , Encéfalo/patologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Esclerose Múltipla Recidivante-Remitente/patologia , Substância Branca/patologia , Adulto JovemRESUMO
A series of novel anthranilic diamides derivatives (7a-s) containing halogen, trifluoromethyl group and cyano group were designed, synthesized, and characterized by melting point, 1H NMR, 13C NMR and elemental analyses. The bioactivity revealed that most of them showed moderate to excellent activities against oriental armyworm (Mythimna separata) and diamondback moth (Plutella xylostella). Above all, the larvicidal activity of 7o against oriental armyworm was 100% and 40% at 0.25 and 0.1â¯mgâ¯L-1, comparable to that of the standard chlorantraniliprole (100%, 0.25â¯mgâ¯L-1 and 20%, 0.1â¯mgâ¯L-1). What is more, 7o against diamondback moth displayed 90% insecticidal activity at 0.01â¯mgâ¯L-1, superior to chlorantraniliprole (45%, 0.01â¯mgâ¯L-1). The experiments 7o on the American cockroach (Periplaneta Americana) heart beating rates (Dorsal vessel) and contractile force were compared with chlorantraniliprole. In addition, 7o could affect the calcium homeostasis in the central neurons of the third larvae of oriental armyworm, which revealed that the ryanodine receptor is the potential target of 7o. The density functional theory (DFT) calculation results revealed the amide bridge, the benzene ring of anthraniloyl moiety and pyrazole ring might play an important role in the insecticidal activity through hydrophobic interactions and π-π conjugations.
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Diamida/química , Inseticidas/síntese química , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Animais , Baratas/efeitos dos fármacos , Baratas/fisiologia , Diamida/síntese química , Diamida/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Inseticidas/química , Inseticidas/toxicidade , Isoxazóis/química , Larva/efeitos dos fármacos , Mariposas/crescimento & desenvolvimento , Mariposas/metabolismo , Teoria Quântica , Canal de Liberação de Cálcio do Receptor de Rianodina/química , Relação Estrutura-AtividadeRESUMO
Reactions of N,N'-bis (salicylidene)-1,2-cyclohexanediamine (H2 L) with mixed lanthanide counterions of LnCl3 ·6H2 O and Ln (NO3 )3 ·6H2 O afford six H2 L lanthanide coordination polymers, e.g. {[Pr(H2 L)2 (NO3 )2 Cl]·2CH2 Cl2 }n (1); {[Ln(H2 L)1.5 (NO3 )3 ]2 ·5CHCl3 ·mCH3 OH}n [Ln = Sm (2), Eu (3), Gd (4), Tb (5) and Yb (6); m = 1 (2-5); m = 0 (6)]. X-ray crystallographic analysis reveals that complex 1 exhibits three-dimensional diamondoid topologic structure and complexes 2-6 are of two-dimensional structure. Luminescent spectra show that complexes 1 and 6 have characteristic near-infrared (NIR) emission of praseodymium (III) and ytterbium (III) ions and complexes 2-5 emit luminescence in the visible region. Complexes 3 and 6 reveal sensitive luminescence responses to formaldehyde.
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Complexos de Coordenação/química , Etilenodiaminas/química , Corantes Fluorescentes/química , Elementos da Série dos Lantanídeos/química , Medições Luminescentes , Polímeros/química , Cristalografia por Raios X , Modelos Moleculares , Estrutura MolecularRESUMO
The pro-inflammatory cytokine interleukin 6 (IL-6), via activating its downstream JAK/STAT3 and Ras/ERK signaling pathways, is involved in cell growth, proliferation and anti-apoptotic activities in various malignancies. To screen inhibitors of IL-6 signaling, we constructed a STAT3 and ERK dual-pathway responsive luciferase reporter vector (Co.RE). Among several candidates, the natural compound 20(S)-25-methoxyl-dammarane-3ß, 12ß, 20-triol (25-OCH3-PPD, GS25) was identified to clearly inhibit the luciferase activity of Co.RE. GS25 was confirmed to indeed inhibit activation of both STAT3 and ERK pathways and expression of downstream target genes of IL-6, and to predominantly decrease the viability of HepG2 cells via induction of cell cycle arrest and apoptosis. Interestingly, GS25 showed preferential inhibition of HepG2 cell viability relative to normal liver L02 cells. Further investigation showed that GS25 could not induce apoptosis and block activation of STAT3 and ERK pathways in L02 cells as efficiently as in HepG2 cells, which may result in differential effects of GS25 on malignant and normal liver cells. In addition, GS25 was found to potently suppress the expression of endogenous STAT3 at a higher concentration and dramatically induce p38 phosphorylation in HepG2 cells, which could mediate its anti-cancer effects. Finally, we demonstrated that GS25 also inhibited tumor growth in HepG2 xenograft mice. Taken together, these findings indicate that GS25 elicits its anti-cancer effects on HepG2 cells through multiple mechanisms and has the potential to be used as an inhibitor of IL-6 signaling. Thus, GS25 may be developed as a treatment for hepatocarcinoma with low toxicity on normal liver tissues as well as other inflammation-associated diseases.
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Antineoplásicos Fitogênicos/farmacologia , Regulação Neoplásica da Expressão Gênica , Ginsenosídeos/farmacologia , Hepatoblastoma/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Fator de Transcrição STAT3/genética , Animais , Antineoplásicos Fitogênicos/síntese química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Proliferação de Células/efeitos dos fármacos , Feminino , Genes Reporter , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Ginsenosídeos/química , Células Hep G2 , Hepatoblastoma/genética , Hepatoblastoma/metabolismo , Hepatoblastoma/patologia , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Luciferases/genética , Luciferases/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Nus , Fator de Transcrição STAT3/agonistas , Fator de Transcrição STAT3/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
Juglans mandshurica Maxim (Juglandaceae) is a famous folk medicine for cancer treatment and some natural compounds isolated from it have been studied extensively. Previously we isolated a type of ω-9 polyunsaturated fatty acid (JA) from the bark of J. mandshurica, however little is known about its activity and the underlying mechanisms. In this study, we studied anti-tumor activity of JA on several human cancer cell lines. Results showed that JA is cytotoxic to HepG2, MDA-MB-231, SGC-7901, A549 and Huh7 cells at a concentration exerting minimal toxic effects on L02 cells. The selective toxicity of JA was better than other classical anti-cancer drugs. Further investigation indicated that JA could induce cell apoptosis, characterized by chromatin condensation, DNA fragmentation and activation of the apoptosis-associated proteins such as Caspase-3 and PARP-1. Moreover, we investigated the cellular apoptosis pathway involved in the apoptosis process in HepG2 cells. We found that proteins involved in mitochondrion (cleaved-Caspase-9, Apaf-1, HtrA2/Omi, Bax, and Mitochondrial Bax) and endocytoplasmic reticulum (XBP-1s, GRP78, cleaved-Caspase-7 and cleaved-Caspase-12) apoptotic pathways were up-regulated when cells were treated by JA. In addition, a morphological change in the mitochondrion was detected. Furthermore, we found that JA could inhibit DNA synthesis and induce G2/M cell cycle arrest. The expression of G2-to-M transition related proteins, such as CyclinB1 and phosphorylated-CDK1, were reduced. In contrast, the G2-to-M inhibitor p21 was increased in JA-treated cells. Overall, our results suggest that JA can induce mitochondrion- and endocytoplasmic reticulum-mediated apoptosis, and G2/M phase arrest in HepG2 cells, making it a promising therapeutic agent against hepatoma.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Ácidos Graxos Insaturados/farmacologia , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Juglans/química , Neoplasias Hepáticas/patologia , Medicina Tradicional Chinesa , Antineoplásicos/isolamento & purificação , Proteína Quinase CDC2 , Carcinoma Hepatocelular/metabolismo , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Ciclina B1/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Ácidos Graxos Insaturados/isolamento & purificação , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Mitocôndrias/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/metabolismo , Transdução de SinaisRESUMO
The mechanism of cleft palate induction by dexamethasone is not fully known. Bone morphogenetic protein-2 (BMP-2) has been associated with dexamethasone-induced osteoporosis. In this study, the authors induced cleft palate models in Institute of Cancer Research mice by dexamethasone to investigate the role of BMP-2 and its transcriptional element GATA-6. The authors injected different doses of dexamethasone into pregnant mice (E13), and assessed the histology of the palatal shelf and the expression levels of BMP-2, GATA-6, and specific apoptosis-related proteins. The results showed that cleft palate formation was dependent on dexamethasone dosage, with high incidence (50.55%) at high concentration (50âmg/kg) compared with the low doses (6âmg/kg, 38.10%). Transmission electron microscopy revealed significant cellular changes of the cleft palate shelf, including loose cell connection, cellular swelling, as well as reduced extracellular matrix and mitochondria. Following exposure to dexamethasone, the apoptotic rate in the palate increased with elevated dosage. Western blotting analysis indicated that the expression levels of GATA-6 and BMP-2 were reduced, while the levels of apoptotic proteins bax and caspase-3 were increased. The results of authors' study suggested that dexamethasone-induced cleft palate formation involved apoptosis occurred in a dose-dependent manner. BMP-2 and GATA-6 mediated dexamethasone-induced cleft palate formation.
Assuntos
Proteína Morfogenética Óssea 2/fisiologia , Fissura Palatina/induzido quimicamente , Fissura Palatina/fisiopatologia , Dexametasona/farmacologia , Fator de Transcrição GATA6/fisiologia , Animais , Apoptose/fisiologia , Proteína Morfogenética Óssea 2/antagonistas & inibidores , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Fator de Transcrição GATA6/antagonistas & inibidores , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos ICR , GravidezRESUMO
To observe the effect of total saponins of Clematidis Radix et Rhizoma (TSCR) on serum metabolic profile changes in adjuvant arthritis(AA) rats, and explore its possible action mechanism for AA rats. The AA rat models were induced by Freund's complete adjuvant(FCA), and their histopathological changes were observed. Gas chromatography-time-of-flight mass spectrometry (GC-TOF-MS), principal component analysis(PCA) and partial least squares-discriminant analysis (PLS-DA) were employed to analyze the metabolic profile among normal group, AA model group and TSCR group. Potential biomarkers in the serum were screened based on the variable importance projection(VIP) value>1, P<0.05. As compared with the normal group, 17 potential biomarkers such as aspartic acid, inositol and phenylacetaldehyde were found and identified in the serum of model group rats. As compared with the model group, the above biomarkers were regulated nearly to a normal state after TSCR administration for 16 days. Metabolomic analysis revealed that the total saponins of Clematidis Radix et Rhizoma has a certain therapeutic effect for AA rats, and the mechanism may be related to regulation of lipid metabolism, amino acid metabolism and energy metabolism.