Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
Phytother Res ; 36(7): 2779-2802, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35561084

RESUMO

Hyperoside is a natural flavonol glycoside in various plants, such as Crataegus pinnatifida Bge, Forsythia suspensa, and Cuscuta chinensis Lam. Medical research has found that hyperoside possesses a broad spectrum of biological activities, including anticancer, anti-inflammatory, antibacterial, antiviral, antidepressant, and organ protective effects. These pharmacological properties lay the foundation for its use in treating multiple diseases, such as sepsis, arthritis, colitis, diabetic nephropathy, myocardial ischemia-reperfusion, pulmonary fibrosis, and cancers. Hyperoside is obtained from the plants and chemical synthesis. This study aims to provide a comprehensive overview of hyperoside on its sources and biological activities to provide insights into its therapeutic potential, and to provide a basis for high-quality studies to determine the clinical efficacy of this compound.


Assuntos
Crataegus , Quercetina , Anti-Inflamatórios/farmacologia , Crataegus/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Quercetina/análogos & derivados , Quercetina/farmacologia
2.
Sci Rep ; 14(1): 14994, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951207

RESUMO

Artificially extracted agricultural phenotype information exhibits high subjectivity and low accuracy, while the utilization of image extraction information is susceptible to interference from haze. Furthermore, the effectiveness of the agricultural image dehazing method used for extracting such information is limited due to unclear texture details and color representation in the images. To address these limitations, we propose AgriGAN (unpaired image dehazing via a cycle-consistent generative adversarial network) for enhancing the dehazing performance in agricultural plant phenotyping. The algorithm incorporates an atmospheric scattering model to improve the discriminator model and employs a whole-detail consistent discrimination approach to enhance discriminator efficiency, thereby accelerating convergence towards Nash equilibrium state within the adversarial network. Finally, by training with network adversarial loss + cycle consistent loss, clear images are obtained after dehazing process. Experimental evaluations and comparative analysis were conducted to assess this algorithm's performance, demonstrating improved accuracy in dehazing agricultural images while preserving detailed texture information and mitigating color deviation issues.

3.
Acta Crystallogr C ; 69(Pt 1): 5-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23282902

RESUMO

In the title metal-organic framework (MOF), [La(C(8)H(8)N(2)O(6))(C(2)O(4))(0.5)(H(2)O)](n), the La(III) cation is coordinated by eight O atoms in a square antiprismatic configuration. Each La(III) cation is connected to adjacent La(III) cations by bridging 2,5-dioxopiperazine-1,4-diacetate (PODC(2-)) and oxalate (lying about an inversion centre) ligands, generating two-dimensional grid layers. The layers are further linked via the carboxylate groups of the PODC(2-) ligands in syn-syn and syn-anti modes, resulting in a three-dimensional framework with a short Schläfli vertex notation of {4(7).6(3)}{4(7).6(7).8}.

4.
Nanotechnology ; 23(5): 055708, 2012 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-22237013

RESUMO

Boron nitride nanotubes (BNNTs) are inappropriate for further chemical derivatization because of their chemical inertness. We demonstrate covalent activation of chemically inert BNNTs by isophorone diisocyanate (IPDI) to form isocyanate group (NCO)-terminated BNNT precursors with an 'NCO anchor' ready for further functionalization. As identified by Fourier transform infrared spectroscopy, a number of molecules or polymers with -COOH, -OH or -NH2 groups are readily attached to the activated IPDI-BNNTs. The IPDI-BNNT-involving polymer composites have shown mechanical properties are considerably improved due to the good dispersibility of IPDI-BNNTs in the polymer matrix and the strong interfacial interactions between BNNTs and polymers. The methodology reported here provides a promising method to promote the chemical reactivity of BNNTs and covalently modify polymer nanocomposites with improved mechanical performance.

5.
J Pharm Pharmacol ; 74(3): 321-336, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-34612502

RESUMO

OBJECTIVES: Fructus arctii (F. arctii) is the dried ripe fruit of Arctium lappa Willd (Asteraceae). It is being used as a traditional medicine in China, Japan, Iran, Europe, Afghanistan, India, etc. for cough, inflammation, clearing the heat, detoxification, cancer and diabetes. This review summarized the botanical description, distribution, ethnopharmacology, bioactive constituents and pharmacological actions of F. arctii including methods to assess its quality. In addition, this review also provides insights into future research directions on F. arctii to further explore its bioactive constituents, mechanism involved in pharmacological activity, and clinical use including the development of new analytical methods for assessing the quality. KEY FINDINGS: The comprehensive analysis of the literature revealed that F. arctii contains lignans, volatile oil, flavonoids, sesquiterpenoids, triterpenes, phenolic acids, etc. Experimental studies on various extracts and drug formulations showed that it has antioxidant, antimicrobial, hypoglycaemic, lipid-lowering, anti-inflammatory, analgesic, antiviral, anti-tumour activity, etc. SUMMARY: The pharmacological activity of a few major constituents in F. arctii have been identified. However, there are still need more studies and more new technologies to prove the pharmacological activity and the effective mechanism of the other constituents that undergoing uncertain. Except for the animal experiments, clinical studies should be carried out to provide the evidence for clinical application.


Assuntos
Arctium/química , Medicina Tradicional/métodos , Extratos Vegetais/farmacologia , Animais , Etnofarmacologia , Frutas , Humanos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química
6.
J Ethnopharmacol ; 275: 114117, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33848612

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Herba Siegesbeckiae, mainly includes Sigesbeckia orientalis L, Sigesbeckiae pubescens Makino and Sigesbeckiae glabrescens Makino. Herba Siegesbeckiae, also known as 'Xi-Xian Cao' (Chinese: ), has been regarded as an important traditional Chinese medicine since Tang dynasty. The dried aerial parts of Herba Siegesbeckiae are also being used as a herbal medicine in many countries such as Japan, Korea and Vietnam. In China, Herba Siegesbeckiae has been used for the treatment of rheumatic arthralgia with aching and weakness of loins and knees, as well as numbness of limbs. AIM OF THIS REVIEW: The aim of this review was to provide critical analysis on the scientific evidence to support the traditional uses of Herba Siegesbeckiae. The information available on its in botanical characteristics, traditional uses, chemical constituents, pharmacological activities, clinical studies, toxicity and quality control was summarized to understand the current research and provided the leas for future study. MATERIALS AND METHODS: The search terms "Herba Siegesbeckiae", "Sigesbeckia orientalis", "Sigesbeckia pubscens" and "Sigesbeckia glabrescens" were used to obtain the information from electronic databases such as Web of Science, China National Knowledge Infrastructure, PubMed, Google Scholar and SciFinder Scholar and other web search instruments (Springer, Yahoo search). The information provided in this review was based on peer-reviewed papers in English and Chinese. Besides, information was also collected from ancient documents. RESULT: The studies showed that Herba Siegesbeckiae contains sesquiterpenoids, diterpenoids, flavonoids and organic acids, etc. Due to these constituents, it displayed numerous pharmacological activities, such as anti-inflammatory, antitumor, antiallergic, antioxidant, antithrombotic and antibacterial activities. In addition, it showed effects in protecting myocardial and cerebral ischemia injury. CONCLUSIONS: According to its traditional uses, chemical constituents, pharmacological activities and clinic studies, Herba Siegesbeckiae is regarded as a promising medical plant with various chemical compounds and numerous pharmacological activities. However, fewer experimental studies were focused on toxicity and quantitative study of 3 species. It suggested that further in-depth study of toxicity and quality control were critical for future evaluation of drug efficacy and safety.


Assuntos
Asteraceae/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa/métodos , Animais , Estudos Clínicos como Assunto , Bases de Dados Factuais , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/história , História Antiga , Humanos , Controle de Qualidade
7.
Phytomedicine ; 86: 153560, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33858739

RESUMO

BACKGROUND: The dried fruits of Brucea javanica (L.) Merr (BJ) is being widely investigated, both in lab and in clinic, to explore its potential anticancer activity and molecular mechanism involved. PURPOSE: We appraised the available literature and suggested the future research directions to improve the medicinal value of BJ. METHOD: In this review, we have summarized the scientific findings from experimental and clinical studies regarding the anticancer activity and mechanisms. RESULTS: Numerous studies have reported that BJ exerts anticancer effect on various types of cancer lines through inhibiting cell proliferation, inducing apoptosis, inhibiting migration/invasion, inducing autophagy and restraining angiogenesis. Brucea javanica triggers the generation of reactive oxygen species (ROS), release of cytochrome C, activation of mitochondrial apoptosis pathway and regulation of a series of signal pathways and proteins related to cancer. The molecular mechanism involved are inhibiting the PI3K/Akt/mTOR, NF-κB and Nrf2-Notch1 pathways; up or down modulating the levels of p53, p62, p21, Bax, and Bcl-2 respectively, and inhibiting the expression of matrix metalloproteinases (MMPs), vascular endothelial growth factor (VEGF), cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2). Brucea javanica's efficacy in treating cancer patients either as a main or supportive treatment is also discussed in this review. CONCLUSION: This review will serve as a comprehensive resource of BJ's potential as anticancer agent and its molecular pathways. The analysis of the literature suggests that BJ can serve as a potential candidate for the treatment of cancer.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Brucea/química , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/farmacologia , Frutas/química , Humanos , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
8.
Nat Mater ; 7(10): 790-4, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18776890

RESUMO

One abiding surprise in fullerene science is that I(h)-symmetric buckminsterfullerene C(60) (ref. 1) (I(h)-C(60) or (#1,812)C(60), the nomenclature specified by symmetry or by Fowler's spiral algorithm) remains the sole C(60) species experimentally available. Setting it apart from the other 1,811 topological isomers (isobuckminsterfullerenes) is its exclusive conformity with the isolated-pentagon rule, which states that stable fullerenes have isolated pentagons. Although gas-phase existence of isobuckminsterfullerenes has long been suspected, synthetic efforts have yet to yield successful results. Here, we report the realization of two isobuckminsterfullerenes by means of chlorination of the respective C(2v)- and C(s)-symmetric C(60) cages. These chlorinated species, (#1,809)C(60)Cl(8)(1) and (#1,804)C(60)Cl(12)(2), were isolated in experimentally useful yields. Structural characterization by crystallography unambiguously established the unique pentagon-pentagon ring fusions. These distinct structural features are directly responsible for the regioselectivity observed in subsequent substitution of chlorines, and also render these unprecedented derivatives of C(60) isomers important for resolving the long-standing puzzle of fullerene formation by the Stone-Wales transformation scheme.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA