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1.
Phytochemistry ; 210: 113677, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37059286

RESUMO

Two pairs of Z/E isomeric benzofuran enantiomers possessing unprecedented carbon skeletons featuring ring cleavage and addition reactions in the α-pyrone ring of furocoumarin, named rutabenzofuran A [(+)-1 and (-)-1], and rutabenzofuran B [(+)-2 and (-)-2], respectively, were isolated as minor compounds from the water extract of the aerial part of Ruta graveolens L. Their structures were determined by extensive spectroscopic data analysis. The absolute configurations were assigned by comparing the optical rotation with previous research and the experimental circular dichroism (CD) spectra with the calculated electronic CD (ECD) spectra. (-)-1, (+)-2, and (-)-2 were evaluated for antibacterial, anticoagulant, anticancer, and acetylcholinesterase (AChE) inhibitory activities. No anticancer or anticoagulant activities were observed, yet (-)-2 exhibited weak antibacterial activity against Salmonella enterica subsp. Enterica. At the same time, (-)-1, (+)-2, and (-)-2 displayed weak inhibitory activity on AChE.


Assuntos
Benzofuranos , Ruta , Ruta/química , Acetilcolinesterase , Componentes Aéreos da Planta/química , Benzofuranos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química
2.
Biomed Pharmacother ; 162: 114635, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37044023

RESUMO

PURPOSE: This study investigated the effects of total alkaloids in Stephania tetrandra (TAS) and the main alkaloid components tetrandrine, fangchinoline and cepharanthine on the biological function of lung cancer cells and the mechanism underlying the synergistic antitumor effects of TAS and cisplatin. METHODS: RNA sequencing analysis was performed on TAS-treated H1299 cells. Differentially expressed genes were identified and analyzed, and the regulatory pathway was identified by gene set enrichment analysis. The mRNA and protein expression levels of the differentially expressed genes in cells were determined using quantitative reverse transcription-polymerase chain reaction and western blotting, respectively. Cell viability and wound healing assays evaluated the biological function of TAS and the main alkaloid components in non-small cell lung cancer (NSCLC) cells. Flow cytometry was used to determine the apoptosis rate in NSCLC cells. RESULTS: TAS inhibited the proliferation and migration of A549 and H1299 cells and increased the apoptosis rate in a time- and dose-dependent manner. When H1299 cells were treated with TAS (7.5 µg/ml), MGLL and BBC3 were identified as the possible differentially expressed genes. Pathways associated with cisplatin resistance were screened to investigate the effect of TAS on the apoptosis of NSCLC cells. TAS may regulate fatty acid metabolism and induce apoptosis through the upregulated expression of MGLL and BBC3. The combination of TAS at noncytotoxic concentrations (A549: 1.0 µg/ml; H1299: 3.0 µg/ml) and cisplatin significantly inhibited the viability of A549 and H1299 cells. CONCLUSION: TAS and the main alkaloid components exert anticancer activity in NSCLC by regulating tumor cell proliferation and apoptosis. Therefore, TAS and the main alkaloid components have the potential to be used as multi-targeted drugs for lung cancer treatment.


Assuntos
Alcaloides , Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Stephania tetrandra , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Cisplatino/farmacologia , Linhagem Celular Tumoral , Alcaloides/farmacologia , Antineoplásicos/farmacologia , Apoptose , Proliferação de Células , Proteínas Proto-Oncogênicas , Proteínas Reguladoras de Apoptose
3.
J Fungi (Basel) ; 8(11)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36422012

RESUMO

The intensive use of antibiotics as growth-promoting agents in animal production has resulted in the spread of animal antibiotic resistance and possibly human antibiotic resistance. Based on this premise, it is significant to explore an alternative approach to preventing infectious diseases and promoting animal growth and health. Yeast as the main natural growth promoter in livestock nutrition has been extensively studied for decades. Numerous yeasts and yeast-containing products are produced, marketed, and used in animal feed as providers of nutrient sources, probiotics, and nutrients or serve distinct nutritional functions. A large amount of scientific research suggests that yeasts and their derivatives may be good for animal growth performance and health, especially when animals are housed in poor sanitation or are suffering from disease. However, when yeasts are used as a surrogate for livestock antibiotics, the results vary according to several factors, including yeast species, yeast product components, feed ingredients, animal category, type of symptoms, and differences in the rearing environment. In this review, the effects of different yeasts on different animals will be reviewed. The types of widely used yeast products, their functional characteristics, and application effects will be discussed in order to provide a reference for the development and application of yeast feed products.

4.
Pharm Biol ; 60(1): 1349-1364, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35868020

RESUMO

CONTEXT: The extracts of Aspongopus chinensis Dallas (Pentatomidae), an insect used in traditional Chinese medicine, have a complex chemical composition and possess multiple pharmacological activities. OBJECTIVE: This study comprehensively characterizes the chemical constituents of A. chinensis by an integrated targeted and untargeted strategy using UPLC-QTOF-MS combined with molecular networking. MATERIALS AND METHODS: The ultra-performance liquid chromatography-tandem quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) combined with molecular networking-based dereplication was proposed to facilitate the identification of the chemical constituents of aqueous and ethanol extracts of A. chinensis. The overall strategy was designed to avoid the inefficiency and costliness of traditional techniques. The targeted compounds discovered in the A. chinensis extracts were identified by searching a self-built database, including fragment ions, precursor ion mass, and other structural information. The untargeted compounds were identified by analyzing the relationship between different categories, fragmentation pathways, mass spectrometry data, and the structure of the same cluster of nodes within the molecular network. The untargeted strategy was verified using commercial standard samples under the same mass spectrometry conditions. RESULTS: The proposed integrated targeted and untargeted strategy was successfully applied to the comprehensive profiling of the chemical constituents of aqueous and ethanol extracts of A. chinensis. A total of 124 compounds such as fatty acids, nucleosides, amino acids, and peptides, including 74 compounds that were reported for the first time, were identified in this study. CONCLUSIONS: The integrated strategy using LC tandem HRMS combined with molecular networking could be popularised for the comprehensive profiling of chemical constituents of other traditional insect medicines.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Etanol , Medicina Tradicional Chinesa , Espectrometria de Massas em Tandem/métodos
5.
Nanoscale ; 11(7): 3216-3221, 2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30706930

RESUMO

The grain size and quality of hybrid organic-inorganic perovskite (HOIP) films greatly affect the performance of perovskite solar cells (PSCs). However, dripping an anti-solvent during the spin coating process induces rapid nucleation and reduces the grain size. Here, a facile method is developed to engineer clusters in precursor solution and obtain high-quality perovskite films with an enlarged grain size. A cluster interfacial modifier, chlorobenzene (CB), is added to precursor solution. The modifier increases the interfacial energy between the precursor cluster and the solvent. The increased interfacial energy suppresses the nucleation and gives rise to HOIP films with large grains and high crystallinity. The efficiency of PSCs based on this method is greatly improved from 17.55% to 19.5%.

6.
Angew Chem Int Ed Engl ; 56(50): 16073-16076, 2017 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-29071807

RESUMO

It is very important to study the crystallization of hybrid organic-inorganic perovskites because their thin films are usually prepared from solution. The investigation on the growth of perovskite films is however limited by their polycrystallinity. In this work, methylammonium lead triiodide single crystals grown from solutions with different methylammonium iodide (MAI):lead iodide (PbI2 ) ratios were investigated. We observed a V-shaped dependence of the crystallization onset temperature on the MAI:PbI2 ratio. This is attributed to the MAI effects on the supersaturation of precursors and the interfacial energy of the crystal growth. At low MAI:PbI2 ratio (<1.7), more MAI leads to the supersaturation of the precursors at lower temperature. At high MAI:PbI2 ratio, the crystal growing plans change from (100)-plane dominated to (001)-plane dominated. The latter have higher interfacial energy than the former, leading to a higher crystallization onset temperature.

7.
Virology ; 330(2): 437-46, 2004 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-15567437

RESUMO

The core gene (C-gene) promoter and regulatory sequences play a central role in the hepatitis B virus (HBV) life cycle. They are essential for the synthesis of the pregenomic and precore mRNA. The pregenomic RNA is the template required for replication and also the template for the synthesis of the core protein and polymerase. Here, we report the in vivo existence and functional characterization of HBV variants that lack the C-gene promoter region and the regulatory sequences located therein. HBV promoter fragments were isolated by PCR from sera of chronic carriers and characterized. Truncated promoter elements were identified, and then tested in the context of wild-type genomes in the HuH-7 cell line. The expression of the recombinant HBV genome resulted in the synthesis of surface proteins, and low level of core protein as well as a transcript pattern similar to, but smaller in size to wild-type virus. The recombinant HBV genome with the truncated promoter region produced pregenomic RNA-like transcripts. These transcripts were encapsidated and reverse transcribed when complemented by sufficient core and polymerase protein. These date provide an explanation as to why such deletion mutants of HBV can be produced at all, they highlight the functional potentials of viral sequences activated by mutations and may be of relevance for viral evolution and persistence.


Assuntos
Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B/genética , Regiões Promotoras Genéticas , Deleção de Sequência , Portador Sadio/virologia , Linhagem Celular , DNA Viral/sangue , DNA Viral/isolamento & purificação , Regulação Viral da Expressão Gênica , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/virologia , Humanos , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese , RNA Viral/biossíntese , Recombinação Genética , Transcrição Gênica , Transfecção , Proteínas Virais/biossíntese
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