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1.
Artigo em Inglês | MEDLINE | ID: mdl-30739881

RESUMO

A general method for efficient and selective extraction of a target compound from complex natural products remains elusive, despite decades of research. By introducing a functional amido group on the surface of dispersity-enhanced magnetic nanoparticles, a nanoparticle receptor to selectively recognize Sibiskoside (a monoterpene) from the aerial portion of Sibiraea angustata by hydrogen bond interaction was synthesized. The superparamagnetic Fe3O4 nanoparticles were successively modified with tetraethyl orthosilicate (TEOS), amino and amido functional groups, and 4-vinylbenzoic acid (VBZA) was used as the functional monomer. A thin layer of poly (VBZA) imprinted with Sibiskoside was immobilized on the surface of magnetic carriers. Attributing to the amido group introduced into the magnetic particles, the template could attract and bind to the surface and promote the formation of a hydrogen bond system between the carrier, template molecules and functional monomer. High-density molecular recognition sites grew on the surface of magnetic substrate. The adsorption reached equilibrium at approximately 150 min, while fast adsorption occurred during the first 60 min. The maximum adsorption capacity has been found to be 13.75 mg g-1 according to calculation with the Langmuir isotherm. The selectivity coefficients of Molecular imprinting polypers (MIPs) for Sibiskoside with respect to Andrographolide, Loganin, Gastrodin, geraniol-1-O-[α-l-rhamnopyranosyl-(1 → 6)-1-ß-d-glucopyranoside] (GRG), Sibiscolacton and Sibiraic acid were 2.26, 1.43, 1.701.56, 1.05, 0.73 and, respectively. The results indicated that the MIPs possessed good specific adsorption capacity and selectivity toward Sibiskoside and had the potential to be a candidate for the separation and purification of monoterpenes from Sibiraea angustata, which is of great significance to obesity management.


Assuntos
Glicosídeos/isolamento & purificação , Nanopartículas de Magnetita/química , Impressão Molecular/métodos , Monoterpenos/isolamento & purificação , Rosaceae/química , Monoterpenos Acíclicos , Cromatografia Líquida de Alta Pressão , Glicosídeos/análise , Monoterpenos/análise , Extratos Vegetais/química , Propriedades de Superfície
2.
Zhongguo Dang Dai Er Ke Za Zhi ; 19(11): 1174-1179, 2017 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-29132465

RESUMO

OBJECTIVE: To investigate the significance of flexible bronchoscopy in children with respiratory diseases. METHODS: A retrospective analysis was performed for the clinical data of 80 children who were hospitalized due to respiratory diseases (including severe pneumonia, Mycoplasma pneumoniae pneumonia with atelectasis/lung consolidation/local emphysema, protracted pneumonia, coughing and wheezing of unknown cause, chronic cough of unknown cause, and laryngeal stridor) and who underwent flexible bronchoscopy/alveolar lavage. RESULTS: Bronchoscopy found that all the 80 children had endobronchial inflammation, among whom 28 children had severe airway obstruction by secretion. Twenty-four children had congenital airway dysplasia besides endobronchial inflammation, and three children had bronchial foreign bodies. In the children with coughing and wheezing of unknown cause and laryngeal stridor, some had congenital airway dysplasia or bronchial foreign bodies. Among the 27 children with Mycoplasma pneumoniae pneumonia, 26 had severe airway obstruction/embolization by secretion; 25 children (93%) underwent chest imaging again at 2 weeks after alveolar lavage, and the results showed complete or partial lung recruitment. Among the 80 children who underwent bronchoscopy, 3 had severe hypoxemia during surgery, 1 had epistaxis, 1 had minor bleeding during alveolar lavage, 3 had transient bronchospasm, and 5 had postoperative fever; these children were all improved after symptomatic treatment. CONCLUSIONS: Flexible bronchoscopy is safe and reliable in children with respiratory diseases. Early alveolar lavage under a flexible bronchoscope is recommended for children with severe/refractory Mycoplasma pneumoniae pneumonia to improve prognosis. Flexible bronchoscopy is recommended for children with recurrent coughing and wheezing and persistent laryngeal stridor, in order to directly observe the throat and airway under an endoscope.


Assuntos
Broncoscopia/métodos , Pneumopatias/diagnóstico , Broncoscopia/efeitos adversos , Criança , Pré-Escolar , Tosse/diagnóstico , Feminino , Humanos , Lactente , Masculino , Pneumonia por Mycoplasma/diagnóstico , Sons Respiratórios/diagnóstico , Estudos Retrospectivos
3.
Zhong Yao Cai ; 38(12): 2535-7, 2015 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-27352533

RESUMO

OBJECTIVE: To investigate the chemical constituents from the shoot of Phyllostachys edulis. METHODS: Normal-phase, reversed-phase silica gel, Sephadex LH-20 porous polymer gel column and HPLC chromatography were used for isolation. Spectroscopic methods (13C-NMR, 1H-NMR, DEPT and EI-MS) were used for identification. RESULTS: Eleven compounds were isolated and elucidated, which were skimmin(I), liquiritienin(II),1-(4-hydroxy-3-methoxyphenyl)-1-propanone(III), syringicaldehyde(IV), vanillin(V), isoliquiritigenin(VI), 4-hydroxybenzoic acid(VII), methyl p-hydroxy benzeneacetate (VIII), 5,7-dihydroxy-8-methoxyflavone (IX), daucosterol(X) and ß-sitosterol(X). CONCLUSION: All the compounds are obtained from this plant for the first time, and compounds VI, VIII and IX are firstly isolated from the plants of this genus.


Assuntos
Compostos Fitoquímicos/análise , Plantas Medicinais/química , Poaceae/química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Espectrometria de Massas
4.
Zhong Yao Cai ; 37(1): 57-60, 2014 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-25090704

RESUMO

OBJECTIVE: To study the chemical constituents from the aerial part of Sibiraea angustata. METHODS: The constituents were isolated by various chromatographic techniques (HP-20 macroporous absorption resin, Sephadex LH-20 gel, RP-MPLC and PHPLC)and their structures were determined on the basis of physicochemical properties and their spectroscopic data,as well as literatures. RESULTS: Eleven compounds were separated and identified as p-methoxycinnamic acid(I), protocatechuic aldehyde(II), quercetin(III), isorhamnetin(IV), quercetin 3-O-beta-D-galactopyranoside (V),9-0-[beta-D-glucopyranoside]-3,4,5-trimethoxy cinnamyl alcohol(VI), syringaresinol-4'-O-beta-D-monoglucoside(VII), ntin(VIII), sibiraic acid(IX), sibiscolacton(X), methyl ferulic acid(XI). CONCLUSION: Compounds I-XIII are isolated from the genus of Sibiraea for the first time.


Assuntos
Medicamentos de Ervas Chinesas/química , Componentes Aéreos da Planta/química , Rosaceae/química , Benzaldeídos/química , Benzaldeídos/isolamento & purificação , Catecóis/química , Catecóis/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Cinamatos/química , Cinamatos/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Galactosídeos/química , Galactosídeos/isolamento & purificação , Quercetina/análogos & derivados , Quercetina/química , Quercetina/isolamento & purificação
5.
J Neurosci Methods ; 137(2): 315-9, 2004 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-15262076

RESUMO

Although the intraluminal thread technique has been used to induce focal cerebral ischaemia in rabbits, its success rate is not high. We, therefore, attempted to improve the stability and reproducibility of this method by using thread tips of appropriate diameter as determined from the anatomical characteristics of the carotid and cerebral arteries of New Zealand white rabbits. Following intraarterial injection of casting material, we tested threads of four different tip diameters to determine the optimal thread tip that could occlude the middle cerebral artery (MCA). 2,3,5-Triphenyltertrazolium chloride (TTC) staining showed that, consistent with the intraluminal diameter of the MCA from the arterial casts ( 0.50 +/- 0.06 mm), thread with 0.51-0.55 mm tip diameter was optimal for the occlusion of the MCA. Ability to induce focal cerebral ischaemia was also dependent on variations in the anatomy of the internal carotid artery (ICA), especially the origin of the occipital artery. Our results suggest that use of appropriately sized thread and accurate manipulation of its tip significantly improves the stability and reproducibility of this model.


Assuntos
Isquemia Encefálica/etiologia , Artérias Cerebrais/cirurgia , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/complicações , Neurologia/métodos , Animais , Isquemia Encefálica/patologia , Circulação Cerebrovascular/fisiologia , Constrição Patológica , Embolização Terapêutica/instrumentação , Lateralidade Funcional , Infarto da Artéria Cerebral Média/patologia , Coelhos , Reprodutibilidade dos Testes , Sais de Tetrazólio
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