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1.
Anal Chim Acta ; 1271: 341460, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37328245

RESUMO

Surface plasmon coupled emission (SPCE), a novel surface-enhanced fluorescence technique, can generate directional and amplified radiation by the intense interaction between fluorophores and surface plasmons (SPs) of metallic nanofilms. For plasmon-based optical systems, the strong interaction between localized and propagating SPs and "hot spot" structures show great potential to significantly improve the electromagnetic (EM) field and modulate optical properties. Au nanobipyramids (NBPs) with two sharp apexes to enhance and restrict the EM field were introduced through electrostatic adsorption to achieve a mediated fluorescence system, and the emission signal enhancement was realized by factors over 60 compared with the normal SPCE. It has been demonstrated that the intense EM field produced by the NBPs assembly is what triggered the unique enhancement of SPCE by Au NBPs, which effectively overcomes the inherent signal quenching of SPCE for ultrathin sample detection. This remarkable enhanced strategy offers the chance to improve the detection sensitivity for plasmon-based biosensing and detection systems, and expand the range of applications for SPCE in bioimaging with more comprehensive and detailed information acquisition. The enhancement efficiency for various emission wavelengths was investigated in light of the wavelength resolution of SPCE, and it was discovered that enhanced emission for multi-wavelength could be successfully detected through the different emission angles due to the angular displacement caused by wavelength change. Benefit from this, the Au NBP modulated SPCE system was employed for multi-wavelength simultaneous enhancement detection under a single collection angle, which could broaden the application of SPCE in simultaneous sensing and imaging for multi-analytes, and expected to be used for high throughput detection of multi-component analysis.


Assuntos
Corantes Fluorescentes , Ressonância de Plasmônio de Superfície , Ressonância de Plasmônio de Superfície/métodos , Corantes Fluorescentes/química
2.
Zhongguo Zhong Yao Za Zhi ; 47(10): 2584-2596, 2022 May.
Artigo em Chinês | MEDLINE | ID: mdl-35718476

RESUMO

As a famous and precious Chinese medicinal material, Panax notoginseng(PN) has been commonly used for a long history in China. As reported, PN exhibits significant pharmacological actions in protecting cardiocerebral vascular system and nervous system and suppressing tumors. In recent years, with the innovation in ideas, as well as the development of methods and equipment, PN has been extensively investigated, and notable progress has been made. This paper reviewed the advancements of PN in recent five years from chemical components, chromatographic analysis, P. notoginseng extracts, and pharmacology, in which the application of PN extracts in quality control was first summarized. The present study aims to provide a theoretical basis for quality control, product development, and rational medication of PN.


Assuntos
Medicamentos de Ervas Chinesas , Panax notoginseng , China , Medicamentos de Ervas Chinesas/uso terapêutico , Panax notoginseng/química , Controle de Qualidade
3.
Bioorg Chem ; 100: 103889, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32388432

RESUMO

The chemical constituents of the roots, seeds, and bark of Azadirachta indica var. siamensis were investigated, leading to the isolation of six tricyclic diterpenoids and five limonoids, including two new compounds (2, 5). The structures were elucidated based on NMR spectroscopic techniques, mass spectrometry and single-crystal X-ray diffraction as well as comparison with the literature. Moreover, the cytotoxicity activities of the isolates were evaluated. The results indicated that the compounds 1-3, 5-9 exhibited cytotoxicities against one or more cancer cell lines tested, with IC50 values in the range of 1.7-88.1 µM. The mechanism of action studies indicated that the most active compound, compound 5, could induce the apoptosis of AZ521 cells. Furthermore, the Western blot analysis showed that compound 5 could reduce the expression levels of procaspases-3, -8, -9 and promote the expression of Bid and AIF.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Azadirachta/química , Diterpenos/química , Diterpenos/farmacologia , Limoninas/química , Limoninas/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Diterpenos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Limoninas/isolamento & purificação , Modelos Moleculares , Neoplasias/tratamento farmacológico
4.
J Ethnopharmacol ; 257: 112778, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32205260

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sauropus androgynus L. Merr is an underexploited perennial shrub traditionally used as a medicinal plant in South Asia and Southeast Asia. The plant is regarded as not just a green vegetable for diet, but as a traditional herb for certain aliments. For instance, it has traditionally been used to relieve fever, to treat ulcers and diabetes, to promote lactation and eyesight, and to reduce obesity. AIM OF THE STUDY: This paper aims to review the botany, phytochemistry, ethnopharmacology, and pharmacological activities of S. androgynus, and discuss the known chemical constituents at work in S. androgynus-induced bronchiolitis obliterans for providing new ideas to the mechanism of the disease and pharmacology research of the plant. MATERIALS AND METHODS: The data presented in this review were collected from published literatures as well as the electronic databases of PubMed, CNKI, Web of Science, SCI finder, ACS, Science Direct, Wiley, Springer, Taylor, Google Scholar, and a number of unpublished resources, (e.g. books, and Ph.D. and M.Sc. dissertations). RESULTS: The scientific literature indicates that S. androgynus is a valuable and popular herbal medicine whose nutritional value is also higher than that of other commonly used vegetables. Phytochemical analyses identified high content of fatty acids, flavonoids, and polyphenols as the major bioactive components in S. androgynus. Crude extracts and phytochemical compounds isolated from S. androgynus show a wide spectrum of in vitro and in vivo pharmacological activities such as antioxidant, anti-inflammatory, anti-ulcer, skin whitening, anti-diabetic, and immunoregulatory activities. The traditional use, such as increasing lactation, treating ulcers and diabetes, and reducing obesity, have been evaluated and studied with various methods. Numerous reports have revealed the unusual link between the consumption of S. androgynus and the induction of a chronic and irreversible obstructive disease (namely, bronchiolitis obliterans), indicating that the toxicity and side effects of this plant that is presently used in health care and medicine are a major area of concern. CONCLUSION: Though little importance was attached to this green plant, S. androgynus has notable phytochemical constituents and various pharmacological activities including antioxidant, anti-inflammatory, and anti-obesity activities. Studies have firmly established the association between excessive consumption of the uncooked S. androgynus juice over a period of time and the occurrence of bronchiolitis obliterans. It is inadvisable to ingest excessive amounts of S. androgynus before fully understanding the pathogenesis and induction mechanism of this fatal disease. The phytochemistry of S. androgynus, its pharmacology for traditional use, S. androgynus-induced bronchiolitis obliterans still need further investigation.


Assuntos
Etnofarmacologia , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/toxicidade , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Animais , Ásia , Humanos , Medicina Tradicional Chinesa , Medicina Tradicional , Compostos Fitoquímicos/química , Fitoterapia , Extratos Vegetais/química , Plantas Medicinais
5.
J Ethnopharmacol ; 248: 112204, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31669442

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ficus hispida L.f. (Moraceae) has long been used as a traditional medicine in India, China, Sri Lanka, Australia, and Myanmar in the treatment of diarrhea, ulcer, anemia, diabetes, inflammation, and cancer. AIM OF THE REVIEW: This review provides a systematic comment on the botany, traditional uses, and phytochemical and pharmacological studies of F. hispida, with an aim to make critical update of the current knowledge and obtain opportunities for further therapeutic potential. MATERIALS AND METHODS: The information was derived from scientific literature databases including PubMed, Baidu Scholar, Google Scholar, Web of Science, and Science Direct. Additional information was gathered from books, Ph.D. and M.Sc. dissertations, and unpublished materials. RESULTS AND DISCUSSION: F. hispida is used especially in Chinese and Indian traditional medical systems as a remedy for skin disorders, respiratory diseases, and urinary diseases. Wound healing, anti-inflammatory, antinociceptive, sedative, antidiarrheal, antiulcer, antimicrobial, antioxidant, hepatoprotective, antineoplastic, and antidiabetic activities have been reported for crude extracts and isolated metabolites, but the methodologies in these studies often have inadequate design and low technical quality. More than 76 compounds have been isolated from F.hispida, including sesquiterpenoids and triterpenoids, flavonoids, coumarins, phenylpropionic acids, benzoic acid derivatives, alkaloids, steroids, other glycosides, and alkanes, but the method of bioassay-guided fractionation is seldom applied in the isolation from F. hispida. CONCLUSION: F. hispida is used widely in traditional medicines and has multiple pharmacological effects that could support traditional uses. However, pharmacological studies should be viewed with caution because of the inappropriate experimental design. More in vitro and in vivo research is urgently needed to study the molecular mechanisms and assess the effective and safe dose of F. hispida.


Assuntos
Ficus , Animais , Humanos , Medicina Tradicional , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Compostos Fitoquímicos/toxicidade , Preparações de Plantas/química , Preparações de Plantas/farmacologia , Preparações de Plantas/uso terapêutico , Preparações de Plantas/toxicidade
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