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3.
J Mass Spectrom ; 52(3): 152-164, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28102926

RESUMEN

Full scan mode of liquid chromatography-mass spectrometry equipped with an electrospray ionization source offers a chance on global detection of complicated components; however, the scan mode carries significant challenges in rapidly capturing information of analysts. Sodiation-based in-source collision was proposed here, as a technique for rapid detecting untargeted analytes in full scan analysis, which was based on the stability of sodium adducts and the nonselectivity of in-source collision. Then the technique was applied to profile of angular-type pyranocoumarins (APs) in Radix Peucedani, with full scan analysis performed at two specific in-source collision energy: a high energy 50 V that is tolerated by the sodium adducts of APs, and a low energy 10 V, at which abundant adducts were offered. The spectra list of two average mass spectra was exported, and stable ions were selected based on the intensity ratio of standards at the two collision energy. Then 27 plausible [M + Na]+ m/z values of APs were acquired after filtering the fragment ion and isotope ions and validating with [M + NH4 ]+ . Eighty-two APs finally were tentatively identified based on their accurate spectral data of MSn , fragmentation rules, and elution order regardless of their absolute configuration, which included 25 reported APs from Peucedanum praeruptorum Dunn. The technique provided a novel application of sodium adduct in qualitative analysis. And it was valuable for rapidly capturing information of analytes in full scan analysis, not only for APs but also for other compounds that could form sodium adducts. Copyright © 2017 John Wiley & Sons, Ltd.


Asunto(s)
Medicamentos Herbarios Chinos/química , Piranocumarinas/análisis , Sodio/química , Calibración , Cromatografía Líquida de Alta Presión/métodos , Humanos , Espectrometría de Masa por Ionización de Electrospray/métodos
4.
Inflamm Res ; 62(3): 313-24, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23266598

RESUMEN

OBJECTIVE: Our previous study demonstrated that polysaccharides of Dendrobium officinale Kimura et Migo (DP) were capable of enhancing immunomodulation in an experimental model of Sjögren's syndrome, a chronic autoimmune disease mainly affecting the salivary glands. In the present study, we further investigated the protective effect of DP on a human salivary gland cell line A-253 against tumor necrosis factor (TNF)-α-induced apoptosis. MATERIALS: TNF-α (100 U/ml) was used as the stimulus for treating the A-253 cells to induce cellular apoptosis. Nuclear factor-kappa B (NF-κB, p65), phosphorylation of mitogen-activated protein kinases (MAPK), reactive oxygen species (ROS) generation, mitochondrial membrane potential and proapoptotic proteins were examined. A-253 cells were pre-treated with DP for 12 h before TNF-α stimulation. RESULTS: We observed translocation of NF-κB into the nuclei, prolonged MAPK, excessive ROS generation and strongly decreased mitochondrial membrane potential, and subsequently cytochrome C release and caspase-3 activation. However, pre-treatment with DP significantly inhibited the TNF-α-induced apoptotic factors. CONCLUSIONS: Our data suggested the inhibitory effect of DP on TNF-α-induced apoptosis in a human salivary gland cell line. This inhibition indicated potential inference of DP in the initial plasma membrane-bound complex of TNF-α and its receptors.


Asunto(s)
Apoptosis/efectos de los fármacos , Dendrobium , Extractos Vegetales/farmacología , Polisacáridos/farmacología , Glándulas Salivales/citología , Glándulas Salivales/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Caspasa 3/metabolismo , Línea Celular , Citocromos c/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Fosforilación , Especies Reactivas de Oxígeno/metabolismo , Glándulas Salivales/metabolismo
5.
J Hazard Mater ; 172(2-3): 1175-84, 2009 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-19709804

RESUMEN

Iron-based mesoporous silica materials were prepared according to different impregnation and co-condensation procedures. Several complementary techniques, including XRD, TEM/EDX and nitrogen sorption isotherms were used to evaluate the final structural and textural properties of the calcined Fe/SBA-15 materials. While Fe(2)O(3) isolated particles of which the size is close to the silica pore diameter ( approximately 7-8 nm) were obtained using classical wet impregnation procedure, smaller iron oxide particles ( approximately 2-4 nm) homogeneously dispersed within the hexagonal pore structure of the SBA15 host support were generated by self-combustion of an impregnated iron-glycinic complex. By contrast, the various co-condensation routes used in this work were less efficient to generate iron oxide nanoparticles inside the silica mesopores. Catalytic performances of the materials were evaluated in the case of total phenol oxidation by H(2)O(2) in aqueous solution at ambient conditions. Large differences in terms of catalytic activity and iron species stability were observed. While the impregnated solids proved to be the most active catalysts (highest Fe(2)O(3) nanoparticles dispersion), iron leaching was observed in aqueous solution, accounting for a homogeneous catalytic contribution. In contrast, the co-condensed samples exhibiting larger iron oxide clusters stabilized over the silica surface proved more efficient as active sites in Fenton catalysis.


Asunto(s)
Hierro/química , Fenol/química , Dióxido de Silicio/química , Catálisis , Compuestos Férricos , Peróxido de Hidrógeno , Nanopartículas , Oxidación-Reducción , Porosidad , Soluciones , Contaminantes Químicos del Agua/química
6.
Zhongguo Zhong Yao Za Zhi ; 26(8): 551-3, 2001 Aug.
Artículo en Chino | MEDLINE | ID: mdl-12776370

RESUMEN

OBJECTIVE: Study on the non-anthraquinone constituents from rhizoma and radix of Rheum sublanceolatum. METHOD: The constituents were isolated through column chromatography and identified on the basis of their physiochemical and spectral data. RESULT: Six non-anthraquinone constituents were isolated and identified as n-octacosanic acid, sitosterol, daucosterol, 2-methyl-5-carboxymethyl-7-hydroxychromone, piceatannol and 6-hydroxymusizin-8-O-beta-D-glucopyranoside. CONCLUSION: All these compounds were firstly isolated from R. sublanceolatum.


Asunto(s)
Plantas Medicinales/química , Rheum/química , Sitoesteroles/aislamiento & purificación , Estilbenos/aislamiento & purificación , Raíces de Plantas/química , Rizoma/química , Sitoesteroles/química , Estilbenos/química
7.
Zhen Ci Yan Jiu ; 21(4): 7-9, 1996.
Artículo en Chino | MEDLINE | ID: mdl-9388310

RESUMEN

Through TCD test, observation on the blood flow dynamics change before and after treatment with 31 cases of the child cerebral atrophy was made. It is found that scalp therapy is able to speed up the blood flow of part artery, especially increase the even blood flow speed of MCA, ACA obviously (P < 0.05), which preliminary shows the mechanism of scalp therapy for child cerebral atrophy mean while. It is found that scalp therapy also has the function to restrain epilepsy.


Asunto(s)
Terapia por Acupuntura/métodos , Parálisis Cerebral/fisiopatología , Circulación Cerebrovascular , Velocidad del Flujo Sanguíneo , Parálisis Cerebral/terapia , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Cuero Cabelludo , Ultrasonografía Doppler Transcraneal
8.
Zhen Ci Yan Jiu ; 18(1): 53-7, 1993.
Artículo en Chino | MEDLINE | ID: mdl-8082281

RESUMEN

Experiments were performed in 57 SD rats. The stress was induced by binding plus revolving (5.5 xg, 170 c/min, 10 min) or cold (0-4 degrees C, 30-60 min). Selected acupuncture points were "Zusanli" and "Weishu". Bipolar Ag-AgCl recording electrodes were respectively implanted on the serous membrane surface of the antrum, duodenum and on the abdominal skin corresponding to above areas. The results were as follows: (1) There are 63.2% individuals in the stress group which showed a large quantity of bleeding points spreading over the gastroduodenal mucosal membrane. The area density of lesion was 15.8-27.7%. Under microscope the signs emerged including mucosal blood vessel dilatation and hyperaemia, gland cell swelling, virlus broken and peeling off and lymph cell accumulating, etc. 84% individuals showed obvious inhibition of gastroduodenal electroactivities including that the amplitude of slow wave was lower, the frequency decreased even the rhythm was disordered, the number of fast wave reduced and the IDMEC III cycle was prolonged. (2) In the group of acupuncture plus stress only 16.7% individuals showed bleeding or hyperaemia, and the lesion area density was only 1.7%. Also the pathohistological changes were obviously decreased. Gastroduodenal electrical changes were hardly seen (27.2%) or the inhibitory state above were significantly reduced (54.5%) when compared with the stress group. There is strong reason to consider that acupuncture could effectively reduce the mucosal lesion and the electrical inhibition of stomach and duodenum induced by stress in rats.


Asunto(s)
Terapia por Acupuntura , Duodeno/fisiopatología , Estómago/fisiopatología , Estrés Fisiológico/fisiopatología , Animales , Femenino , Enfermedades Gastrointestinales/fisiopatología , Mucosa Intestinal/patología , Masculino , Ratas , Ratas Sprague-Dawley
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