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1.
Nat Commun ; 11(1): 66, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31898693

RESUMO

Lieb lattice has been predicted to host various exotic electronic properties due to its unusual Dirac-flat band structure. However, the realization of a Lieb lattice in a real material is still unachievable. Based on tight-binding modeling, we find that the lattice distortion can significantly determine the electronic and topological properties of a Lieb lattice. Importantly, based on first-principles calculations, we predict that the two existing covalent organic frameworks (COFs), i.e., sp2C-COF and sp2N-COF, are actually the first two material realizations of organic-ligand-based Lieb lattice. Interestingly, the sp2C-COF can experience the phase transitions from a paramagnetic state to a ferromagnetic one and then to a Néel antiferromagnetic one, as the carrier doping concentration increases. Our findings not only confirm the first material realization of Lieb lattice in COFs, but also offer a possible way to achieve tunable topology and magnetism in organic lattices.

2.
Carbohydr Polym ; 230: 115564, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887953

RESUMO

Herein, we report a novel magnetic bifunctional ß-cyclodextrin nanocomposite (Fe3O4@ß-CD-CDI) based on metal coordination, which may be used for adsorption and degradation of persistent organic pollutants in aqueous solution. More importantly, N,N'-carbonyldiimidazole (CDI) functionalized ß-CD ligand (ß-CD-CDI) was assembled on the surface of Fe3O4 by Zn-N interaction. The results of kinetic and isothermal adsorption model investigation indicated that the adsorption rate and capacity of Fe3O4@ß-CD-CDI were better than other materials, suggesting the effective accessibility of adsorption sites. We further confirmed that Fe3O4@ß-CD-CDI can be used as heterogeneous catalyst to remove BPA through Fenton-like reaction in the presence of hydrogen peroxide (H2O2). Moreover, the material effectively alleviated the secondary pollution owing to the existence of ß-CD inner cavity. This study indicated that the magnetic Fe3O4@ß-CD-CDI material has great potential applications in wastewater purification containing persistent organic pollutants.

3.
Front Plant Sci ; 10: 1230, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31636648

RESUMO

Myrosinase enzymes and their substrate glucosinolates provide a specific defensive mechanism against biotic invaders in the Brassicaceae family. In these plants, myrosinase hydrolyzes glucosinolates into diverse products, which can have direct antibiotic activity or function as signaling molecules that initiate a variety of defense reactions. A myrosinase, ß-thioglucoside glucohydrolase 1 (TGG1) was previously found to be strikingly abundant in guard cells, and it is required for the abscisic acid (ABA) response of stomata. However, it remains unknown which particular physiological processes actually involve stomatal activity as modulated by TGG1. In this experimental study, a homologous TGG1 gene from broccoli (Brassica oleracea var. italica), BoTGG1, was overexpressed in Arabidopsis. The transgenic plants showed enhanced resistance against the bacterial pathogen Pseudomonas syringae pv. tomato (Pst) DC3000 via improved stomatal defense. Upon Pst DC3000 infection, overexpressing BoTGG1 accelerated stomatal closure and inhibited the reopening of stomata. Compared with the wild type, 35S::BoTGG1 was more sensitive to ABA- and salicylic acid (SA)-induced stomatal closure but was less sensitive to indole-3-acetic acid (IAA)-inhibited stomatal closure, thus indicating these hormone signaling pathways were possibly involved in stomatal defense regulated by TGG1. Furthermore, overexpression of BoTGG1 delayed flowering by promoting the expression of FLOWERING LOCUS C (FLC), which encodes a MADS-box transcription factor known as floral repressor. Taken together, our study's results suggest glucosinolate metabolism mediated by TGG1 plays a role in plant stomatal defense against P. syringae and also modulates flowering time by affecting the FLC pathway.

4.
Science ; 365(6452)2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31371578

RESUMO

Diatoms play important roles in global primary productivity and biogeochemical cycling of carbon, in part owing to the ability of their photosynthetic apparatus to adapt to rapidly changing light intensity. We report a cryo-electron microscopy structure of the photosystem II (PSII)-fucoxanthin (Fx) chlorophyll (Chl) a/c binding protein (FCPII) supercomplex from the centric diatom Chaetoceros gracilis The supercomplex comprises two protomers, each with two tetrameric and three monomeric FCPIIs around a PSII core that contains five extrinsic oxygen-evolving proteins at the lumenal surface. The structure reveals the arrangement of a huge pigment network that contributes to efficient light energy harvesting, transfer, and dissipation processes in the diatoms.


Assuntos
Proteínas de Ligação à Clorofila/química , Diatomáceas/enzimologia , Complexo de Proteína do Fotossistema II/química , Carotenoides , Microscopia Crioeletrônica , Multimerização Proteica
5.
Bioorg Chem ; 91: 103167, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31398599

RESUMO

Three new alkaloids, iizukines C-E (1-3), including two aspochalasins (1 and 2), and one brasiliamide derivative (3), along with two known aspochalasins, rosellichalasin (4) and cytochalasin Z17 (5), were isolated from the culture of Aspergillus iizukae. Compound 1 was the first aspochalasin uniquely featuring a 1,2,4-triazole functionality, and 3 showed a pair of NMR signals in CDCl3 with a ratio of about 2:1 due to the existence of conformational isomers. Their structures were determined by extensive spectroscopic analyses and single-crystal X-ray diffractions. In particular, the 1,2,4-triazole moiety in 1 was assigned on the basis of extremely valuable 1H-15N HMBC spectrum. Compound 1 exhibited cytotoxic effect towards HL-60 and A549 cell lines with IC50 values of 3.8 and 7.2 µM, respectively.

6.
Phys Chem Chem Phys ; 21(35): 19234-19241, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31441491

RESUMO

The two-dimensional (2D) material family is expanding fast as novel metal chalcogenides are being continually fabricated and intriguingly, plenty of them are ideal candidates for future nanoscale electronic and magnetic devices. Based on first-principles calculations, we investigated the electronic and magnetic properties of α/ß-In2Se3 monolayers. We find singularities of density of states appear in the valence band and hole doping (such as a Se atom substituted by a lower valence atom) can induce various ferromagnetic phase transitions in the α/ß-In2Se3 monolayers. In particular, replacement by arsenic at the anion site can enhance ferromagnetism and drive α-In2Se3 to be a robust half-metal and ß-In2Se3 to be a bipolar magnetic semiconductor. Then, we proposed spin-polarized field-effect transistors based on α-In2Se3 and a bipolar field-effect spin-filter based on ß-In2Se3. Besides, we also discussed the influences of the molecules in air on the device performance such as carrier mobility. We found that the adsorption of either O2 or H2O on α/ß-In2Se3 induced changes in hole mobility in different directions. These findings reveal a new road to electronic and magnetic modulations in 2D materials.

7.
Molecules ; 24(14)2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31330867

RESUMO

Three new γ-hydroxyl butenolides (1-3), a pair of new enantiomeric spiro-butenolides (4a and 4b), a pair of enantiomeric cyclopentenones (5a new and 5b new natural), and six known compounds (6-11), were isolated from Aspergillus sclerotiorum. Their structures were established by spectroscopic data and electronic circular dichroism (ECD) spectra. Two pairs of enantiomers [(+)/(-)-6c and (+)/(-)-6d] obtained from the reaction of 6 with acetyl chloride (AcCl) confirmed that 6 was a mixture of two pairs of enantiomers. In addition, the X-ray data confirmed that 7 was also a racemate. The new metabolites (1-5) were evaluated for their inhibitory activity against cancer and non-cancer cell lines. As a result, compound 1 exhibited moderate cytotoxicity to HL60 and A549 with IC50 values of 6.5 and 8.9 µM, respectively, and weak potency to HL-7702 with IC50 values of 17.6 µM. Furthermore, compounds 1-9 were screened for their antimicrobial activity using the micro-broth dilution method. MIC values of 200 µg/mL were obtained for compounds 2 and 3 towards Staphylococcus aureus and Escherichia coli, while compound 8 exhibited a MIC of 50 µ/mL towards Candida albicans.


Assuntos
4-Butirolactona/análogos & derivados , Aspergillus/química , Ciclopentanos/química , Microbiologia do Solo , Solo/química , 4-Butirolactona/química , 4-Butirolactona/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclopentanos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Análise Espectral , Relação Estrutura-Atividade
8.
Anal Biochem ; 581: 113340, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31226253

RESUMO

Colorectal cancer (CRC) is the third most common cancer worldwide. To date, no non-invasive and specific biomarkers have been identified for the diagnosis of CRC. The analysis of volatile organic compounds (VOCs) is attracting increasing attention and provides the possibility of a non-invasive diagnosis. Solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) have been used to analyze the VOCs released from the headspace gas of LS174T (Dukes' type B colorectal adenocarcinoma) cells, arsenic trioxide (ATO)-treated LS174T cells and the blood from tumor-bearing mice. The data were processed using principal component analysis (PCA) and orthogonal partial least-squares discriminant analysis (OPLS-DA), which showed that the levels of decanal, 2,4-dimethyl- heptane, and twelve other metabolites were significantly greater in the headspace gas of the LS174T cells and blood of tumor-bearing mice. Additionally, in vivo experiments indicated that formic acid, ethenyl ester and p-trimethylsilyloxyphenyl-(trimethylsilyloxy)trimethylsilylacrylate were consumed during tumor growth. In conclusion, VOCs such as 1-methoxy-hexane and 2,4-dimethyl-heptane could be useful diagnostic markers for CRC. Further research should focus on the potential metabolic pathways associated with these profiles.

9.
J Phys Condens Matter ; 31(28): 285302, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-30952153

RESUMO

Molecular electronics aims at integrating controllable molecular devices into circuits or machines to realize certain functions. According to device configuration, molecular field-effect transistors with top-gate electrodes have great advantages for integration. Nevertheless, from technical aspects, it is difficult to control lateral scale and position of a top-gate electrode precisely. Therefore, one problem arises in how lateral scaling and positioning effects of a top-gate electrode affect device performance. To solve this problem, the electronic transport properties of single-molecule field-effect transistor configurations modulated by a series of partial-scale top-gate electrodes with different lateral scales and positions are studied by using non-equilibrium Green's function in combination with density functional theory, and compared with those of the full gate electrode (can be considered as a bottom gate electrode). The results show that lateral scaling and positioning effects indeed have a great impact on electronic transport properties of single-molecule field-effect transistor configurations. For [Formula: see text]-saturated 1,12-dodecanedithiol devices, larger lateral scale of a partial-scale top-gate electrode obtains larger amplification coefficient [Formula: see text] (ratio of device conductances with/without a gate electrode), and even larger [Formula: see text] than that of the full gate electrode. While lateral positioning effect has little influence on this device. For [Formula: see text]-conjugated 1,3,5,7,9,11-dodehexaene-1,12-dithiol devices, performance of a partial-scale top-gate electrode mainly depends on locations of its two edges, i.e. the number of [Formula: see text] bonds that it breaks. These results will provide theoretical directions in device designing and manufacturing in the future.

10.
Environ Pollut ; 250: 639-649, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31035146

RESUMO

Magnetic ß-cyclodextrin (ß-CD) porous polymer nanospheres (P-MCD) was fabricated by one-pot solvent thermal method using ß-CD immobilized Fe3O4 magnetic nanoparticles with tetrafluoroterephthalonitrile as the monomer. Compared with the ß-CD polymerization method reported in the literature,_ENREF_1 the synthetic route is effective and simple, thereby overcoming the harsh conditions that require nitrogen protection and always maintain anhydrous and oxygen-free. Moreover, the immobilization of ß-CD on magnetic nanoparticles is combined with the cross-linking polymerization of the cross-linker, leading to a good synergistic effect on the removal of contaminants. Meanwhile, the dispersibility of the magnetic carrier enhances the dispersion of the ß-CD porous polymer in the aqueous phase, and improves the inclusion adsorption performance and the adsorption process. P-MCD exhibited superior adsorption capacity and fast kinetics to MB. The maximum adsorption capacity of MB for P-MCD was 305.8 mg g -1, which is more than ß-CD modified Fe3O4 magnetic nanoparticles (Fe3O4@ß-CD). Moreover, the material had a short equilibrium time (5 min) for MB, high recovery and good recyclability (the adsorption efficiency was still above 86% after five repeated uses).


Assuntos
Magnetismo , Nanosferas , Poluentes Químicos da Água/química , Purificação da Água/métodos , beta-Ciclodextrinas/química , Adsorção , Cinética , Polímeros/química , Porosidade
11.
Phys Chem Chem Phys ; 21(14): 7559-7566, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30899930

RESUMO

Due to their proper band gaps (between 1.40 eV and 2.34 eV), newly fabricated tin monochalcogenides (SnX, X = S, Se) and dichalcogenides SnX2, whose monolayer formation energies are much smaller than MoS2, are promising materials for harvesting visible light. Moreover, the anisotropic carrier mobility is up to 2486.93 cm2 V-1 s-1 for SnSe and 2181.96 cm2 V-1 s-1 for SnS2. By applying low tensile strain, the band edge of SnX can be lowered to meet the criteria for water splitting. Meanwhile, the photo-generated exciton binding energies are pretty low, which indicates that the electron-hole can separate efficiently, and may lead to remarkable activity for photocatalysis. Promisingly, it is possible to stack SnS and SnS2 to fabricate a vertical heterostructure (VHT). According to band analysis, we found that the global valence and conduction bands are from SnX and SnX2, respectively. Due to the weak interaction between the two monolayers, the optical gaps can slightly decrease in the two monolayers compared to those in the corresponding isolated ones. Therefore, the VHT can meet the two primary conditions of a photocatalyst for water splitting to generate H2 in SnX and O2 in SnX2. The strong electronegativity difference between the two layers develops an effective potential gradient between the SnS and SnS2 layers, which evokes an effective electric field between them. Thus, it is of benefit for quick charge separation and inter-layer charge transfer. High efficiency of light harvesting can be realized, and improved photocatalytic efficiency.

12.
J Pharm Biomed Anal ; 167: 30-37, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30738241

RESUMO

Early diagnosis and early treatment are important factors in reducing colorectal cancer (CRC) metastasis and mortality. Volatile organic compounds (VOCs) released by the human body have great potential for use in clinical diagnosis and therapeutic monitoring for CRC. The aim of our study was to identify VOCs with high specificity and high sensitivity for CRC and to provide a method for early diagnosis of CRC. Gas chromatography-mass spectrometry (GC-MS) was utilized to analyze metabolites in both the in vivo and in vitro experimental groups. In vivo, VOCs were analyzed in the blood of mice after cell inoculation and tumor resection. In vitro experiments were performed by comparing changes in VOCs in an HCoEpiC cell group, control group, SW620 cell group and Arsenic trioxide + SW620 group. We observed changes in VOCs in a series of CRC SW620 cells in vivo and in vitro. Among these changes, we found that the concentrations of 8 substances, including acetone, increased with tumor growth. Nine substances were found to be significantly elevated in the SW620 cancer cell group compared with the other groups. Only one substance was consumed by the tumor in both the in vivo and in vitro experiments. Our study showed that alkanes, lipids, alcohols, ketones, aldehyde, butylated hydroxytoluene (BHT) and hexamethylcyclotrisiloxane all existed at different levels in SW620 CRC cells compared to those in normal cells. We need more research to further confirm this hypothesis.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Colorretais/metabolismo , Compostos Orgânicos Voláteis/análise , Animais , Arseniatos , Biomarcadores Tumorais/sangue , Linhagem Celular Tumoral , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/sangue
13.
Anticancer Agents Med Chem ; 19(4): 515-527, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30747080

RESUMO

BACKGROUND: Peniciketal A (Pe-A), a spiroketal compound, shows potent anticancer activities in human acute monocytic leukemia. However, the detailed mechanisms and potent targets of Pe-A remain largely unexplored. Here, we investigated the differentially expressed proteins between the Pe-A-treated group and the control group on human acute monocytic leukemia cell line THP-1. METHODS: The DEPs were analyzed by the liquid chromatography-tandem mass spectrometry (LC-MS/MS) with TMT label. The function and feature of the identified proteins were analyzed by the bioinformatic analysis. Western blotting was used to evaluate protein expression. RESULTS: The DEPs were primarily sub located in the cytoplasm and the nucleus by regulating 21 pathways enriched through the Kyoto Encyclopedia of Genes and Genomes (KEGG). Moreover, we preliminarily demonstrated that glucose-6-phosphate 1-dehydrogenase (G6PD), prolow-density lipoprotein receptor-related protein 1 (LRP1) and Calreticulin (CALR) might be the potent targets of Pe-A on death induction of THP-1 cells. CONCLUSION: Collectively, this study not only provides a global proteomic profile as the supplementary data of our previous studies but also provides interesting information that Pe-A may exert more bio-activities.


Assuntos
Leucemia Monocítica Aguda/tratamento farmacológico , Proteômica , Piranos/uso terapêutico , Compostos de Espiro/uso terapêutico , Cromatografia Líquida , Humanos , Células THP-1 , Espectrometria de Massas em Tandem
14.
Toxicol Appl Pharmacol ; 366: 1-9, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30660475

RESUMO

Peniciketal A (Pe-A), a spiroketal compound, is isolated from the saline soil-derived fungus Penicillium raistrickii. However, the underlying molecular mechanistic basis for the effects of Pe-A on leukemia is poorly understood. Here, we investigated that Pe-A reduced cell proliferation in three leukemia cell lines (THP-1, K562 and HL60). Importantly, Pe-A showed little cytotoxicity in primary mouse embryonic fibroblast (MEF) cells in a long-duration treatment. For the mechanistic research, we identified 3449 differentially expressed Pe-A-induced proteins through liquid chromatography-tandem mass spectrometry (LC-MS/MS) with TMT label in THP-1 cells. Results showed that many identified proteins were involved in apoptosis and/or autophagy. Then, we confirmed that Pe-A induced not only apoptosis via the mitochondrial pathway but also cytoprotective autophagy by activating the AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) signaling pathway indeed. In addition, Pe-A also arrested the cell cycle at the G0-G1 phase by regulating the expressions of checkpoint protein. Collectively, these results provide new insights into the mechanisms that Pe-A may target autophagy-related or apoptosis-related pathways to suppress the development of human leukemia.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células , Leucemia/tratamento farmacológico , Piranos/farmacologia , Compostos de Espiro/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/efeitos dos fármacos , Proteínas Relacionadas à Autofagia/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Células HL-60 , Humanos , Células K562 , Leucemia/metabolismo , Leucemia/patologia , Camundongos , Proteômica/métodos , Piranos/toxicidade , Transdução de Sinais/efeitos dos fármacos , Compostos de Espiro/toxicidade , Células THP-1 , Serina-Treonina Quinases TOR/metabolismo , Espectrometria de Massas em Tandem
15.
Molecules ; 24(3)2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30678274

RESUMO

Liver cancer is a very common and significant health problem. Therefore, powerful molecular targeting agents are urgently needed. Previously, we demonstrated that secalonic acid-F (SAF) suppresses the growth of hepatocellular carcinoma (HCC) cells (HepG2), but the other anticancer biological functions and the underlying mechanism of SAF on HCC are unknown. In this study, we found that SAF, which was isolated from a fungal strain in our lab identified as Aspergillus aculeatus, could inhibit the progression of hepatocellular carcinoma by targeting MARCH1, which regulates the PI3K/AKT/ß-catenin and antiapoptotic Mcl-1/Bcl-2 signaling cascades. First, we confirmed that SAF reduced the proliferation and colony formation of HCC cell lines (HepG2 and Hep3B), promoted cell apoptosis, and inhibited the cell cycle in HepG2 and Hep3B cells in a dose-dependent manner. In addition, the migration and invasion of HepG2 and Hep3B cells treated with SAF were significantly suppressed. Western blot analysis showed that the level of MARCH1 was downregulated by pretreatment with SAF through the regulation of the PI3K/AKT/ß-catenin signaling pathways. Moreover, knockdown of MARCH1 by small interfering RNAs (siRNAs) targeting MARCH1 also suppressed the proliferation, colony formation, migration, and invasion as well as increased the apoptotic rate of HepG2 and Hep3B cells. These data confirmed that the downregulation of MARCH1 could inhibit the progression of hepatocellular carcinoma and that the mechanism may be via PI3K/AKT/ß-catenin inactivation as well as the downregulation of the antiapoptotic Mcl-1/Bcl-2. In vivo, the downregulation of MARCH1 by treatment with SAF markedly inhibited tumor growth, suggesting that SAF partly blocks MARCH1 and further regulates the PI3K/AKT/ß-catenin and antiapoptosis Mcl-1/Bcl-2 signaling cascade in the HCC nude mouse model. Additionally, the apparent diffusion coefficient (ADC) values, derived from magnetic resonance imaging (MRI), were increased in tumors after SAF treatment in a mouse model. Taken together, our findings suggest that MARCH1 is a potential molecular target for HCC treatment and that SAF is a promising agent targeting MARCH1 to treat liver cancer patients.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ubiquitina-Proteína Ligases/metabolismo , Xantonas/farmacologia , beta Catenina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/genética , Camundongos , Ubiquitina-Proteína Ligases/efeitos adversos , Ubiquitina-Proteína Ligases/genética , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Biomed Pharmacother ; 109: 806-814, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30551534

RESUMO

The antitumor effect of hydroxysafflor yellow A (HSYA), an active ingredient of the herb Carthamus tinctorius L. (Asteraceae) (safflower), was investigated in the current work. Researches of HSYA on vasculogenesis inhibition, along with the related molecular mechanisms, including the expression of MMP-2, MMP-9, and p38MAPK (COX-2, ATF-2, p-p38MAPK, and p38MAPK) signaling pathway in H22 tumor-bearing mice or HepG2 cells were performed. The animal experiments proved the level of MMP-2 and MMP-9 in H22-transplanted tumor tissue in mice markedly decreased by HSYA, and results both in vivo and in vitro confirmed that COX-2 expression was reduced significantly via p38MAPK|ATF-2 signaling pathway. According to the outcomes, HSYA suppressed p38MAPK phosphorylation in a concentration-dependent manner, while exerting no effect on the total p38MAPK protein expression. It was also showed that suppression of p38 activation by SB203580 decreased the HepG2 cell viability, proliferation, and migration, wherein HSYA exhibited a similar effect. Furthermore, Western blot analysis on caspase-3 and cleaved-caspase-3 revealed that HSYA could induce apoptosis of HepG2 cells. These findings provided experimental evidences that HSYA might be a promising anticancer agent for HCC.


Assuntos
Carcinoma Hepatocelular/enzimologia , Chalcona/análogos & derivados , Neoplasias Hepáticas/enzimologia , Neovascularização Patológica/enzimologia , Quinonas/uso terapêutico , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Chalcona/farmacologia , Chalcona/uso terapêutico , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Pigmentos Biológicos/farmacologia , Pigmentos Biológicos/uso terapêutico , Quinonas/farmacologia
17.
Mar Drugs ; 16(11)2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30445748

RESUMO

Five new (1⁻5) and two known xanthones (6 and 7), one of the latter (6) obtained for the first time as a natural product, together with three known anthraquinones, questin, penipurdin A, and questinol, were isolated from the coastal saline soil-derived Aspergillus iizukae by application of an OSMAC (one strain many compounds) approach. Their structures were determined by interpretation of nuclear magnetic resonance (NMR) and high-resolution electrospray ionization mass spectroscopy (HRESIMS) data, as well as comparison of these data with those of related known compounds. Antiviral activity of xanthones 1-7 was evaluated through the cytopathic effect (CPE) inhibition assay, and compound 2 exhibited distinctly strong activity towards influenza virus (H1N1), herpes simplex virus types 1 (HSV-1) and 2 (HSV-2) with IC50 values of 44.6, 21.4, and 76.7 µM, respectively, which indicated that it was worth to further investigate it as a potential lead compound. The preliminary structure-activity relationship of the xanthones is discussed.


Assuntos
Antivirais/farmacologia , Aspergillus/química , Xantonas/farmacologia , Animais , Antivirais/química , Antivirais/isolamento & purificação , Cães , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Concentração Inibidora 50 , Células Madin Darby de Rim Canino , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Solo/química , Microbiologia do Solo , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade , Xantonas/química , Xantonas/isolamento & purificação
18.
Nanomicro Lett ; 10(3): 40, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30393689

RESUMO

Lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) have received much attention in energy storage system. In particular, among the great efforts on enhancing the performance of LIBs and SIBs, yolk-shell (YS) structured materials have emerged as a promising strategy toward improving lithium and sodium storage. YS structures possess unique interior void space, large surface area and short diffusion distance, which can solve the problems of volume expansion and aggregation of anode materials, thus enhancing the performance of LIBs and SIBs. In this review, we present a brief overview of recent advances in the novel YS structures of spheres, polyhedrons and rods with controllable morphology and compositions. Enhanced electrochemical performance of LIBs and SIBs based on these novel YS structured anode materials was discussed in detail.

19.
Mar Drugs ; 16(6)2018 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-29912165

RESUMO

Three new diastereomers of polyketides (PKs), raistrickiones A−C (1⁻3), together with two new analogues, raistrickiones D and E (4 and 5), were isolated from a highly productive strain of Penicillium raistrickii, which was subjected to an experimental thermo-change strategy to tap its potential of producing new secondary metabolites. Metabolites 1 and 2 existed in a diastereomeric mixture in the crystal packing according to the X-ray data, and were laboriously separated by semi-preparative HPLC on a chiral column. The structures of 1⁻5 were determined on the basis of the detailed analyses of the spectroscopic data (UV, IR, HRESIMS, 1D, and 2D NMR), single-crystal X-ray diffractions, and comparison of the experimental and calculated electronic circular dichroism spectra. Compounds 1⁻5 represented the first case of 3,5-dihydroxy-4-methylbenzoyl derivatives of natural products. Compounds 1⁻5 exhibited moderate radical scavenging activities against 1,1-diphenyl-2-picrylhydrazyl radical 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH).


Assuntos
Compostos de Bifenilo/química , Depuradores de Radicais Livres/química , Penicillium/metabolismo , Picratos/química , Policetídeos/química , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Cristalografia por Raios X , Depuradores de Radicais Livres/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Policetídeos/isolamento & purificação , Estereoisomerismo , Temperatura Ambiente
20.
Anal Chem ; 90(8): 5280-5289, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29570974

RESUMO

Online monitoring of exhaled propofol concentration is important for anesthetists to provide adequate anesthesia as propofol concentrations in plasma and breath are correlated reasonably well. Exhaled propofol could be detected by 63Ni ion mobility spectrometry in negative ion mode; however, the radioactivity of 63Ni source restricts its clinical application due to safety, environmental, and regulatory concerns. An acetone-assisted negative photoionization ion mobility spectrometer (AANP-IMS) using a side-mounted vacuum ultraviolet (VUV) lamp in the unidirectional (UD) flow mode was developed for sensitive measurement of exhaled propofol by producing a high percentage of O2-(H2O) n. An adsorption sampling and time-resolved purge introduction system was developed to eliminate the interference of residual inhaled anesthetic sevoflurane based on their different adsorptions between propofol and sevoflurane on the inwall of the fluorinated ethylene propylene (FEP) sample loop. The effects of the inner diameter and the length of the sample loop on the signal intensity of propofol and the time-resolution between propofol and sevoflurane were theoretically and experimentally investigated. A sample loop with 3 mm i.d. and 150 cm length allowed sensitive measurement of exhaled propofol with a response time of 4 s, a linear response range for propofol was achieved to be 0.2 to 14 ppbv with a limit of detection (LOD) of 60 pptv, and the quantification of propofol was not influenced by the change of the sevoflurane concentration. Finally, the performance of monitoring exhaled propofol during surgery was demonstrated on a patient undergoing laparoscopic distal pancreatectomy combined with cholecystectomy.


Assuntos
Acetona/química , Expiração , Monitorização Intraoperatória , Sistemas On-Line , Propofol/análise , Testes Respiratórios , Humanos , Espectrometria de Mobilidade Iônica , Fatores de Tempo
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