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1.
Nano Lett ; 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32348146

RESUMO

Because of the toxicity of lead, searching for a lead-free halide perovskite semiconducting material with comparable optical and electronic properties is of great interest. Rare-earth-based halide perovskite represents a promising class of materials for this purpose. In this work, we demonstrate the solution-phase synthesis of single-crystalline CsEuCl3 nanocrystals with a uniform size distribution centered around 15 nm. The CsEuCl3 nanocrystals have photoluminescence emission centered at 435 nm, with a full width at half-maximum of 19 nm. Furthermore, CsEuCl3 nanocrystals can be embedded in a polymer matrix that provides enhanced stability under continuous laser irradiation. Lead-free rare-earth cesium europium halide perovskite nanocrystals represent a promising candidate to replace lead halide perovskites.

2.
Sci Rep ; 10(1): 6540, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32300172

RESUMO

Clinical reports on hepatotoxicity that arise from Rhizoma Paridis have recently received widespread attention. Because the hepatotoxicity mechanism is little understood, this research strived to investigate the hepatotoxicity mechanism of Rhizoma Paridis extracts based on iTRAQ quantitative proteomics and metabonomics. The extraction solutions were administrated to rats for 7 days by gavage, and the hepatotoxicity was assessed through quantification of biochemical indexes and Oil red O staining. Additionally, the mechanism of hepatotoxicity was investigated by metabonomics based upon GC-MS and iTRAQ quantitative proteomics. The biochemical and histopathological analysis stood out that Rhizoma Paridis extract could induce liver injury, which was proved by the formation of fat droplets, the changes of mitochondrial structure, and biochemical parameters. The iTRAQ proteomics and metabonomics revealed that Rhizoma Paridis-induced hepatotoxicity was chiefly connected with the abnormal activity of mitochondrion function, which brought about oxidative stress injuries and inflammation, finally causing cell apoptosis. Collectively, we have provided previously uncharacterized hepatotoxic mechanism induced by Rhizoma Paridis and a reference to ensure its safe use in the future.

3.
Microb Pathog ; 143: 104162, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32194180

RESUMO

Dendritic cells (DCs) are key linkages between innate immunity and acquired immunity. The antigens that promote the functions of DCs might be the effective candidates of novel vaccine. In this research, the ability of ubiquitin-conjugating enzyme (UCE), a recognized common antigens among chicken Eimeria species, to stimulate DCs of chickens were evaluated. We cloned UCE gene from Eimeria maxima (EmUCE), and its protein expression was confirmed by SDS-PAGE and western-blot. Immunofluorescence assay confirmed the binding of rEmUCE on the surface of chicken splenic-derived DCs (ChSP-DCs). Flow cytometric analysis showed that rEmUCE-treated ChSP-DCs increased MHCII, CD1.1, CD11c, CD80, and CD86 phenotypes. qRT-PCR indicated that transcript levels of maturation markers CCL5, CCR7, and CD83 in ChSP-DCs were upregulated in response to rEmUCE. Following rEmUCE treatment, chSP-DCs activated TLR signaling and inhibited Wnt signaling. Moreover, rEmUCE promoted DC-mediated T-cell proliferation in DC/T-cell co-incubation. Interestingly, CD3+/CD4+ T-cells were significantly enhanced when rEmUCE-treated chSP-DCs were co-incubated with T-cells. Cytokine secretion pattern of rEmUCE-stimulated ChSP-DCs revealed that the production of IL-12 and IFN-γ was increased whereas IL-10 and TGF-ß were unchanged. Likewise, the co-incubation of ChSP-DCs with T-cells indicated increased production of IFN-γ but not IL-4. Collectively, rEmUCE could polarize DCs to immunogenic phenotype and shift the immune cells towards Th1 response. Our observations provide valuable insight for future research aimed at vaccine development against avian coccidiosis.

4.
Parasite ; 27: 18, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32195662

RESUMO

Eimeria acervulina is one of seven Eimeria spp. that can infect chicken duodenal epithelial cells. Eimeria microneme protein 3 (MIC3) plays a vital role in the invasion of host epithelial tissue by the parasite. In this study, we found that chicken (Gallus gallus) ubiquitin conjugating enzyme E2F (UBE2F) could bind to the MIC3 protein of E. acervulina (EaMIC3), as screened using the yeast two-hybrid system, and that it might be the putative receptor protein of EaMIC3. The UBE2F gene was cloned from chicken duodenal epithelial cells. The recombinant protein of UBE2F (rUBE2F) was expressed in E. coli and the reactogenicity of rUBE2F was analyzed by Western blot. Gene sequencing revealed that the opening reading frame (ORF) of UBE2F was 558 base pairs and encoded a protein of 186 amino acids with a molecular weight of 20.46 kDa. The predicted UBE2F protein did not contain signal peptides or a transmembrane region, but had multiple O-glycosylation and phosphorylation sites. A phylogenetic analysis showed that the chicken UBE2F protein is closely related to those of quail and pigeon (Coturnix japonica and Columba livia). A sporozoite invasion-blocking assay showed that antisera against rUBE2F significantly inhibited the invasion of E. acervulina sporozoites in vitro. Animal experiments indicated that the antisera could significantly enhance average body weight gains and reduce mean lesion scores following a challenge with E. acervulina. These results therefore imply that the chicken UBE2F protein might be the target receptor molecule of EaMIC3 that is involved in E. acervulina invasion.

5.
J Phys Chem A ; 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32096402

RESUMO

Inorganic lead halide perovskite nanostructures show promise as the active layers in photovoltaics, light emitting diodes, and other optoelectronic devices. They are robust in the presence of oxygen and water, and the electronic structure and dynamics of these nanostructures can be tuned through quantum confinement. Here we create aligned bundles of CsPbBr3 nanowires with widths resulting in quantum confinement of the electronic wave functions and subject them to ultrafast microscopy. We directly image rapid one-dimensional exciton diffusion along the nanowires, and we measure an exciton trap density of roughly one per nanowire. Using transient absorption microscopy, we observe a polarization-dependent splitting of the band edge exciton line, and from the polarized fluorescence of nanowires in solution, we determine that the exciton transition dipole moments are anisotropic in strength. Our observations are consistent with a model in which splitting is driven by shape anisotropy in conjunction with long-range exchange.

6.
Ecotoxicol Environ Saf ; 190: 110073, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31851898

RESUMO

Dysosma Versipellis (DV), a traditional Chinese medicine, has the functions of eliminating phlegm, detoxification, dispersing knots . However, its serious toxicity limits its further use. Therefore, it is necessary to conduct a comprehensive toxicity study of DV, screen the basis of potential toxic substances and understand its toxic mechanism. Based on the concept of toxicological evidence chain (TEC), this study utilizes the technologies and means of chemomics, metabolomics, molecular docking and network toxicology flexibly, step by step to find the evidence of potential toxic components in the development of hepatotoxicity induced by DV, evidence of critical toxicity events, evidence of adverse outcomes, thus, a chain of toxicity evidence with reference and directivity can be organized. It further confirmed the toxic damage and potential molecular mechanism of DV. 5 potential toxic components were identified, namely, Podophyllotoxin-4-O-D-glucoside, Podorhizol, Podophyllotoxin, Podophyllotoxone and 3',4'-O,O-Didemethylpophyllotoxin. These chemical constituents affect phenylalanine metabolism, glycerophospholipid metabolism, energy metabolism and other related pathways by regulating PAH, SOD1, SOD2 and other related targets, then it induces oxidative stress, cell apoptosis, inflammatory reaction and energy consumption, which ultimately induces the occurrence of liver injury. The results of this study provide some reference for the follow-up analysis of toxicity mechanism of DV.


Assuntos
Berberidaceae , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Compostos Fitoquímicos/toxicidade , Animais , Apoptose/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Masculino , Medicina Tradicional Chinesa , Metabolômica , Simulação de Acoplamento Molecular , Estresse Oxidativo/efeitos dos fármacos , Compostos Fitoquímicos/análise , Ratos Wistar
7.
Toxicol Appl Pharmacol ; 383: 114785, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31629732

RESUMO

Celastrol (CS), an active triterpene derived from traditional Chinese medicine Tripterygium wilfordii Hook. f, has been used to treat chronic inflammation, arthritis and other diseases. However, it has been reported that CS can trigger cardiotoxicity and the molecular mechanism of heart injury induced by CS is not clear. Considering the wide application of Tripterygium wilfordii Hook. f in clinics, it is necessary to develop an accurate and reliable method to assess the safety of CS, and to elucidate as much as possible the mechanism of cardiotoxicity induced by CS. In this study, Ultra-performance liquid chromatography coupled with quadrupole time of flight mass spectrometry (UPLC-Q-TOF/MS)-based metabolomics revealed clues to the mechanism of CS-induced heart injury. Palmitic acid significantly increased in plasma from CS-treated rats, and this increase resulted in oxidative stress response in vivo. Excessive ROS further activate TNF signaling pathway and caspase family, which were obtained from the KEGG enrichment analysis of network toxicology strategy. Protein expression level of caspase-3, caspase-8, bax were significantly increased by western blot. Q-PCR also showed the similar results as western blot. It means that apoptosis plays a key role in the process of celastrol induced cardiotoxicity. Blocking this signal axis may be a potential way to protect myocardial tissue.

8.
Zhongguo Zhong Yao Za Zhi ; 44(3): 433-440, 2019 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30989904

RESUMO

Realgar is a mineral traditional medicine with definite efficacy. The function of realgar is detoxicating, insecticiding, eliminating dampness and phlegm, etc. It is widely applied in clinical practice by compatibility medicines. However, the safety and scientificalness of clinical application are questioned because of the toxic effect caused by arsenic compounds. At present, there are still many problems in the research of realgar, which are mainly manifested in three areas: the expression of main components and effective substances are inconsistent; the anti-tumor mechanism is difficult to explain at the molecular level; the mechanism of compatibility is not clear. As a result, realgar and realgar-containing Chinese patent medicines are frequently prohibited from entering the international market, and the reputation of traditional Chinese medicine is also damaged. This paper would analyze the research status of realgar at home and abroad as well as its problems from its main components, effective substances, anti-tumor mechanism and compatibility mechanism. In view of these difficulties, quantum chemical calculation method is proposed to solve them, so as to make up for the shortcomings and limitations of experimental technology and experimental conditions, reduce the cost of realgar research and improve research efficiency. Moreover, it provides inspiration for research of other mineral medicine.


Assuntos
Arsenicais/farmacologia , Medicina Tradicional Chinesa , Sulfetos/farmacologia , Minerais
9.
Fitoterapia ; 134: 165-171, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30825572

RESUMO

Two novel phenanthrenoids, juncuenin H (1) and dijuncuenin B (2), together with eight known phenanthrenoids, effusol (3), dehydroeffusol (4), juncusol (5), dehydrojuncusol (6), juncuenin B (7), dehydrojuncuenin B (8), juncuenin A (9), and dehydrojuncuenin A (10), were isolated from the underground parts of Juncus setchuenensis. The structures of the compounds were determined by 1D and 2D NMR and mass spectroscopy. The anxiolytic activities of compounds 1, 6, 9, and 10 were evaluated. In order to explore the mechanisms underlying their anxiolytic activities, the levels of serotonin (5-HT), dopamine (DA), and their metabolites in the cerebral cortex and hippocampus of mice treated with compound 1 were determined by quantitative mass spectrometry. The mice treated with compound 1 had significantly lower levels of 5-HT, 3-methoxytyramine (3-MT), 5-hydroxyindole-3-acetic acid (5-HIAA), homovanillic acid (HVA), and 3, 4-dihydroxyphenylacetic acid (DOPAC) in the cerebral cortex than those of the vehicle control-treated mice. The levels of HVA and 5-HIAA in the hippocampus were also significantly lower in the mice treated with compound 1 than in the control group mice. These results suggest that the metabolic changes, reflected in the levels of DA and/or 5-HT, may contribute to the anxiolytic activity of the phenanthrenoids studied herein.


Assuntos
Ansiolíticos/farmacologia , Córtex Cerebral/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Magnoliopsida/química , Fenantrenos/farmacologia , Ácido 3,4-Di-Hidroxifenilacético/análise , Animais , Ansiolíticos/isolamento & purificação , Córtex Cerebral/química , China , Dopamina/análogos & derivados , Dopamina/análise , Hipocampo/química , Ácido Homovanílico/análise , Masculino , Camundongos , Estrutura Molecular , Fenantrenos/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Raízes de Plantas/química , Serotonina/análise
10.
Zhongguo Zhong Yao Za Zhi ; 43(22): 4528-4533, 2018 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30593249

RESUMO

This study was aimed to explore the effects of tannins in Galla Chinensis on rifampicin in vivo. In the experiment in vitro, UV spectrophotometry and high performance liquid chromatography (HPLC) were used to investigate the solubility of rifampin in pH 1.3, 6.8, artificial gastric juice environment and artificial intestinal fluid environment as well as the effects of tannins on solubility of rifampin in the above conditions. In the experiment in vivo, the process of rifampicin was studied after intragastric administration of rifampicin and rifampicin+ tannins in Galla Chinensis, and then the pharmacokinetic parameters were calculated. The results showed that rifampicin was constantly precipitated in the artificial gastric juice environment over time, and nearly 85% of the rifampicin was precipitated after 6 hours; it showed a good solubility in the artificial intestinal juice environment. After adding the said tannins, the concentration of rifampicin was decreased significantly in both environments, and the concentration of rifampicin in artificial intestinal juice remained relatively stable, while that in artificial gastric juice remained the original downward trend. The pharmacokinetic parameters displayed that as compared with rifampicin alone, AUC0-t and Cmax were decreased significantly, MRT0-t slowed down significantly, Tmax doubled to 7.0 h and the bioavailability was only 31.65% in rifampicin + tannins in Galla Chinensis group. The experiment indicated rifampicin had a poor solubility in acidic environment and the decrease of bioavailability of rifampicin when in combination with tannin was mainly due to the reduction of rifampicin solubility in intestinal tract by complexation of rifampicin with tannin, thus affecting its absorption in intestinal tract. Therefore, rifampicin and the Chinese herbal medicines or Chinese patent medicines rich in tannin should not be taken simultaneously.


Assuntos
Medicamentos de Ervas Chinesas , Rifampina/farmacocinética , Taninos
11.
Adv Mater ; 30(48): e1802856, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30198087

RESUMO

Halide perovskites have emerged as a class of promising semiconductor materials owing to their remarkable optoelectronic properties exhibiting in solar cells, light-emitting diodes, semiconductor lasers, etc. Inorganic halide perovskites are attracting increasing attention because of the higher stability toward moisture, light, and heat as compared with their organic-inorganic hybrid counterparts. In particular, inorganic halide perovskite nanomaterials provide controllable morphology, tunable optoelectronic properties, and improved quantum efficiency. Here, the development controlled synthesis of desired inorganic halide perovskite nanostructures by various chemical approaches is described. Utilizing these nanostructures as platforms, anion exchange chemistry for wide compositional and optical tunabilities is described, and the rich structural phase transition phenomenon and mechanism investigated systematically. Furthermore, these nanostructures and extracted knowledge are applied to design photonic, photovoltaic, and thermoelectric devices. Finally, future directions and challenges toward improvement of the optical, electrical, and optoelectronic properties, exploration of the anion and cation exchange kinetics, and alleviation of the stability and toxicity issues in inorganic lead based halide perovskites are discussed to provide an outlook on this promising field.

12.
Nano Lett ; 18(11): 6967-6973, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-30265549

RESUMO

Surface condition plays an important role in the optical performance of semiconductor materials. As new types of semiconductors, the emerging metal-halide perovskites are promising for next-generation optoelectronic devices. We discover significantly improved light-emission efficiencies in lead halide perovskites due to surface oxygen passivation. The enhancement manifests close to 3 orders of magnitude as the perovskite dimensions decrease to the nanoscale, improving external quantum efficiencies from <0.02% to over 12%. Along with about a 4-fold increase in spontaneous carrier recombination lifetimes, we show that oxygen exposure enhances light emission by reducing the nonradiative recombination channel. Supported by X-ray surface characterization and theoretical modeling, we propose that excess lead atoms on the perovskite surface create deep-level trap states that can be passivated by oxygen adsorption.

13.
Vet Parasitol ; 258: 114-123, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30105971

RESUMO

E. mitis is ubiquitous in clinical coccidiosis caused by mixed infection of Eimeria species and the infection by E. mitis usually significantly impairs productivity of the infected chickens. To date, however, few protective antigens from E. mitis have been reported. In this study, the molecular characterization and protective efficacy of microneme 3 of Eimeria mitis (EmiMIC3) were analyzed. EmiMIC3 gene was cloned from sporozoites of E. mitis and its MARs (microneme adhesive repeats domain) were predicted. Recombinant EmiMIC3 (rEmiMIC3) was expressed in E. coli and purified and then was analyzed by western blot with anti-E. mitis chicken serum. Meanwhile, native EmiMIC3 from sporozoites was analyzed by anti-rEmiMIC3 rat serum. The expressions of EmiMIC3 in E. mitis sporozoites and merozoites were analyzed by immunofluorescence assay. The rEmiMIC3-induced changes of T lymphocytes subpopulation, serum cytokines and IgY levels and the protective efficacy of rEmiMIC3 were determined in animal experiments. The results showed that the deduced open reading frame (ORF) of EmiMIC3 was composed of 1145 amino acids, possessing 9 MARs. EmiMIC3 gene was submitted to GenBank (accession number: MG888670). EmiMIC3 could express in sporozoites and merozoites respectively and located at the apex of E. mitis sporozoite. Western blot assay revealed that the rEmiMIC3 could be recognized by serum of chicken infected by E. mitis and the native EmiMIC3 from sporozoites could also be recognized by rat serum against rEmiMIC3. Following vaccination with rEmiMIC3, higher levels of IL-10, IFN-γ, TGF-ßand IL-17, higher proportions of CD4+/CD3+ and CD8+/CD3 + T lymphocytes and higher level of IgY antibody were induced compared to the controls. Vaccination with rEmiMIC3 prominently increased the weight gains and decreased oocyst output of the vaccinated chickens after challenge infection. Our result not only enriches protective candidate antigen of E. mitis, but also provides available protective antigen of E. mitis for the development of multivalent vaccines against infection caused by mixture of Eimeria species in clinical coccidiosis.


Assuntos
Coccidiose/veterinária , Eimeria/genética , Doenças das Aves Domésticas/prevenção & controle , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Vacinação/veterinária , Animais , Galinhas , Clonagem Molecular , Coccidiose/imunologia , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Eimeria/imunologia , Escherichia coli/genética , Imunogenicidade da Vacina , Imunoglobulinas/sangue , Merozoítos/genética , Fases de Leitura Aberta/genética , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/parasitologia , Proteínas de Protozoários/administração & dosagem , Vacinas Protozoárias/administração & dosagem , Vacinas Protozoárias/imunologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Esporozoítos/genética , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética , Vacinas de DNA/imunologia
14.
Nano Lett ; 18(6): 3502-3508, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29719146

RESUMO

Replacing lead in halide perovskites is of great interest due to concerns about stability and toxicity. Recently, lead free double perovskites in which the unit cell is doubled and two divalent lead cations are substituted by a combination of mono- and trivalent cations have been synthesized as bulk single crystals and as thin films. Here, we study stability and optical properties of all-inorganic cesium silver(I) bismuth(III) chloride and bromide nanocrystals with the double perovskite crystal structure. The cube-shaped nanocrystals are monodisperse in size with typical side lengths of 8 to 15 nm. The absorption spectrum of the nanocrystals presents a sharp peak, which we assign to a direct bismuth s-p transition and not to a quantum confined excitonic transition. Using this spectroscopic handle combined with high-resolution transmission electron microscopy (TEM) based elemental analysis, we conduct stoichiometric studies at the single nanocrystal level as well as decomposition assays in solution and observe that Ag+ diffusion and coalescence is one of the pathways by which this material degrades. Drying the nanocrystals leads to self-assembly into ordered nanocrystal solids, and these exhibit less degradation than nanocrystals in solution. Our results demonstrate that Cs2AgBiX6 (X = Cl, Br) nanocrystals are a useful model system to study structure-function relationships in the search for stable nontoxic halide perovskites.

15.
J Zhejiang Univ Sci B ; 19(3): 227-244, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29504316

RESUMO

Danshen, the dried root of Salvia miltiorrhiza Bunge (Lamiaceae), is one of the traditional Chinese medicines (TCMs) most commonly used for the treatment of cardiovascular and cerebrovascular diseases. However, little is known about the chemical and metabolic profiles of danshen in vitro or in vivo. In particular, more information is needed in relation to the 50% ethanol extracts usually used in danshen formulations such as Fufang Xueshuantong Capsules and Fufang Danshen tablets. High-performance liquid chromatography coupled with a linear ion trap-Orbitrap mass spectrometer (HPLC-LTQ-Orbitrap) provides a sensitive and accurate method for analyzing the composition of samples. This method was used to determine the in vitro and in vivo chemical and metabolic profiles of danshen. Sixty-nine components of danshen extract and 118 components of danshen in rat plasma, urine, feces, and bile were unambiguously or tentatively identified. These results not only revealed the material composition of danshen, but also provided a comprehensive research approach for the identification of multi-constituents in TCMs.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/metabolismo , Animais , Medicamentos de Ervas Chinesas/análise , Masculino , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas por Ionização por Electrospray
16.
Molecules ; 22(12)2017 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-29210995

RESUMO

Natural small-molecule phenols (NSMPs) share some bioactivities. The anxiolytic activity of NSMPs is attracting attention in the scientific community. This paper provides data supporting the hypothesis that NSMPs are generally anxiolytic. The anxiolytic activities of seven simple phenols, including phloroglucinol, eugenol, protocatechuic aldehyde, vanillin, thymol, ferulic acid, and caffeic acid, were assayed with the elevated plus maze (EPM) test in mice. The oral doses were 5, 10 and 20 mg/kg, except for phloroglucinol for which the doses were 2.5, 5 and 10 mg/kg. All tested phenols had anxiolytic activity in mice. The phenolic hydroxyl group in 4-hydroxycinnamic acid (4-OH CA) was essential for the anxiolytic activity in the EPM test in mice and rats compared to 4-chlorocinnamic acid (4-Cl CA). The in vivo spike recording of rats' hippocampal neurons also showed significant differences between 4-OH CA and 4-Cl CA. Behavioral and neuronal spike recording results converged to indicate the hippocampal CA1 region might be a part of the anxiolytic pathways of 4-OH CA. Therefore, our study provides further experimental data supporting NSMPs sharing anxiolytic activity, which may have general implications for phytotherapy because small phenols occur extensively in herbal medicines.


Assuntos
Ansiolíticos/química , Ansiolíticos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Fenóis/química , Fenóis/farmacologia , Animais , Ansiedade/tratamento farmacológico , Comportamento Animal , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Estrutura Molecular , Ratos
17.
Zhongguo Zhong Yao Za Zhi ; 42(8): 1557-1565, 2017 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29071862

RESUMO

Phenolic compounds have multiple bioactivities, such as anti-oxidant, anti-tumor, anti-bacterial, and anti-inflammatory activities. Recent literatures have demonstrated that flavonoids have a significant anti-anxiety effect on the central nervous system. In addition, studies showed that flavonoids acted as pro-drugs, which were transformed into smaller phenols through intestinal microflora. The small phenolic metabolites were crucial for the anxiolytic effects of these flavonoids, indicating that natural small-molecule phenols(NSMP) generally have anxiolytic activities. In this paper, the supporting evidences (before June 2016) from SciFinder database have been summarized. Furthermore, NSMPs were classified according to chemical structures; their anxiolytic effects, mechanisms, and the structure-activity relationships were also discussed.


Assuntos
Ansiolíticos/farmacologia , Flavonoides/farmacologia , Fenóis/farmacologia , Relação Estrutura-Atividade
18.
Zhongguo Zhong Yao Za Zhi ; 42(7): 1258-1264, 2017 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29052383

RESUMO

Mineral Chinese medicine is the distinctive part of the Chinese traditional medicine. The mineral Chinese medicines containing mercury elements such as cinnabaris, calomelas and hydrargyri oxydum rubrum are widely applied in the clinical conditions because of their efficacy of sedative, sterilization, removing necrotic tissue and promoting granulation. However, the rationality and security of clinical application are questioned because of the toxic effect caused by mercury compounds. This paper would summarize the efficacy of the mineral Chinese medicines containing mercury element, as well as their hepatotoxicity, nephrotoxicity, embryotoxicity, and neurotoxicity effect and mechanisms. Improper usage or high dose of the mineral Chinese medicines containing mercury element would cause acute hepatotoxicity. Cinnabaris, calomelas and hydrargyri oxydum rubrum may lead to chronic hepatotoxicity, nephrotoxicity, embryotoxicity and neurotoxicity when they were applied externally to the skin for long-term use. In addition to the accumulation of mercury elements in the tissues and organs, the species and forms of mercury compounds absorbed into the body in different ways, should be also studied in order to understand the toxicity of the mineral Chinese medicines containing mercury element. Meanwhile the dose and period of treatment shall be also considered in order to provide the references for rational and safe clinical application of the mineral Chinese medicines containing mercury element.


Assuntos
Medicina Tradicional Chinesa/efeitos adversos , Compostos de Mercúrio/toxicidade , Minerais/toxicidade , Mercúrio
19.
Phys Chem Chem Phys ; 19(39): 26765-26775, 2017 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-28948251

RESUMO

It is important to understand the interface and interaction between the graphene layer, titanium carbide [TiC(111)] interlayer, and silicon carbide [SiC(0001[combining macron])] substrates in epitaxial growth of graphene on silicon carbide (SiC) substrates. In this study, the fully relaxed interfaces which consist of up to three layers of TiC(111) coatings on the SiC(0001[combining macron]) as well as the graphene layers interactions with these TiC(111)/SiC(0001[combining macron]) were systematically studied using the density functional theory-D2 (DFT-D2) method. The results showed that the two layers of TiC(111) coating with the C/C-terminated interfaces were thermodynamically more favorable than one or three layers of TiC(111) on the SiC(0001[combining macron]). Furthermore, the bonding of the Ti-hollow-site stacked interfaces would be a stronger link than that of the Ti-Fcc-site stacked interfaces. However, the formation of the C/Ti/C and Ti/C interfaces implied that the first upper carbon layer can be formed on TiC(111)/SiC(0001[combining macron]) using the decomposition of the weaker Ti-C and C-Si interfacial bonds. When growing graphene layers on these TiC(111)/SiC(0001[combining macron]) substrates, the results showed that the interaction energy depended not only on the thickness of the TiC(111) interlayer, but also on the number of graphene layers. Bilayer graphene on the two layer thick TiC(111)/SiC(0001[combining macron]) was thermodynamically more favorable than a monolayer or trilayer graphene on these TiC(111)/SiC(0001[combining macron]) substrates. The adsorption energies of the bottom graphene layers with the TiC(111)/SiC(0001[combining macron]) substrates increased with the decrease of the interface vertical distance. The interaction energies between the bottom, second and third layers of graphene on the TiC(111)/SiC(0001[combining macron]) were significantly higher than that of the freestanding graphene layers. All of these findings provided insight into the growth of epitaxial graphene on TiC(111)/SiC(0001[combining macron]) substrates and the design of graphene/TiC/SiC-based electronic devices.

20.
J Zhejiang Univ Sci B ; 18(4): 343-352, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28378572

RESUMO

Fufang Xueshuantong (FXT) is a well-known Chinese herbal formula which has been used to treat cardiovascular and ophthalmic diseases, especially diabetic retinopathy. Panax notoginseng (Burkill) F.H. Chen (PN) is the main herb of FXT, whose major bioactive constituents are ginsenosides. However, the scientific basis of the compatibility of FXT is still ambiguous. The present study investigated the scientific basis of the compatibility of FXT by comparing the pharmacokinetics of marker compounds after oral administrations of PN and FXT. A high performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) method was developed for simultaneous detection of notoginsenoside R1 (NR1), ginsenoside Rg1 (GRg1), and ginsenoside Rb1 (GRb1) in rat plasma. The pharmacokinetic studies of FXT and PN were performed using the established method with the pharmacokinetic parameters being determined by non-compartmental analysis. The results showed that the pharmacokinetic parameters (maximum concentration, area under the curve (AUC0-t), clearance, and mean residence time) of NR1, GRg1, and GRb1 were significantly different after oral administration of FXT (P<0.05) compared with PN. The AUC0-t values of GRg1 and GRb1 were 1.7- and 3.4-fold greater, respectively, in FXT than in PN. The compatible herbs of FXT could prolong the retention time and increase the systemic exposure of NR1, GRg1, and GRb1 compared with PN in vivo, providing some scientific basis for the compatibility and clinical use of FXT.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Panax notoginseng/química , Administração Oral , Animais , Análise Química do Sangue , Fármacos Cardiovasculares/administração & dosagem , Fármacos Cardiovasculares/farmacocinética , Cromatografia Líquida de Alta Pressão , Retinopatia Diabética/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/química , Ginsenosídeos/administração & dosagem , Ginsenosídeos/farmacocinética , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
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