Biomedical subjects

Yun Huang

Publications and source records attributed to Yun Huang.

22 records · Page 2Linked to original sources

PubMed2003

[RbcL sequence analysis of Belamcanda chinensis and related medicinal plants of Iris].

AIM: To identify "Shegan" [Belamcanda chinensis (L.) DC.] and relative medicinal plants of Iris including Iris tectorum Maxim., I. dichotoma Pall., I. germanica L. and I. japonica Thunb. by ribulose 1,5-bisphosphate carboxylase Large Gene (rbcL) sequence analysis. METHODS: General DNA was isolated from the fresh leaves of Belamcanda chinensis and 4 Iris spp. by CTAB. A pair of primers was designed to amplify the rbcL gene and PCR Preps DNA kit was used to purify the PCR products. The rbcL sequences were determined by ABI (Applied Biosystems Inco.) Prism 310 Genetic Analyzer. RESULTS: A fragment of about 750 bp of rbcL gene from Belamcanda chinensis and 4 Iris spp. were amplified and sequenced. The rbcL sequences of Iris tectorum, I. dichotoma Pall. and I. japonica were reported for the first time. The rbcL sequences of 5 species of Iridaceae were aligned and analyzed using Clustal (Version 8.0) and MEGA (Version 2.0.) programs. The nucleotide number of difference is from 1.000 to 20.000. The tranversions is from 0.000 to 9.000 and the transitions is from 0.000 to 14.000. Phylogenetic tree based on rbcL partial sequence data indicated that the eleven samples of 5 species clustered separately. CONCLUSION: The sequence variation of rbcL can be used to identify Belamcanda chinensis and 4 species of relative medicinal plants of Iris. The molecular phylogenetic tree accords with the classical taxonomy.

Base Sequence↗

PubMed2003

Effect of micronized fenofibrate on vascular endothelial function in patients with hypertriglyceridemia.

OBJECTIVE: To investigate the effect of micronized fenofibrate on vascular endothelial function in patients with hypertriglyceridemia. METHODS: Using high-resolution ultrasound, we measured flow- and nitroglycerin-induced dilatation of the brachial artery in 30 patients with hypertriglyceridemia before and after treatment with micronized fenofibrate at a dose of 200 mg once daily for 4 weeks. Simultaneously, both serum lipid and plasma endothelin (ET) levels were determined. RESULTS: After micronized fenofibrate therapy, serum triglyceride (TG) levels decreased significantly (P < 0.05). Plasma ET levels also decreased markedly [(82.66 +/- 15.46) microg/L vs. (106.22 +/- 19.16) microg/L, P < 0.001]. Flow-induced vasodilatation was much improved (11.0% +/- 9.0% vs 2.7% +/- 2.0%, P < 0.01). However, no significant changes in vasodilatation occurred in response to nitroglycerin (16.2% +/- 6.0% vs 15.0% +/- 5.0%, P > 0.05) in patients with hypertriglyceridemia. CONCLUSIONS: Micronized fenofibrate can improve impaired endothelium-dependent vasodilatation in patients with hypertriglyceridemia. Improving endothelial function may also be the mechanism responsible for the beneficial effects of micronized fenofibrate.

Adult↗

PubMed2002

Norethindrone acetate (NA) and ethinyl estradiol (EE) related oxidative transformation products in stability samples of formulated drug product: synthesis of authentic references.

Preparative chemical methods for the synthesis of eight oxidative transformation products of ethinyl estradiol (EE) and norethindrone acetate (NA) are described. The prepared materials are useful as reference materials and standards for pharmaceutical analysis of EE and NA as bulk chemical or in formulated product. All eight products result from oxidation of the A and/or B rings of the parent compounds. Oxidation of the heteroannular 3,5 dienyl acetate derivative of NA resulted in the 6 alpha-hydroxy, 6 beta-hydroxy and 6-keto NA. Oxidation of 6-keto NA led to the preparation of 6 alpha-hydroxy, 6 beta-hydroxy, 6-keto- and Delta(6) EE. Delta(11) EE was prepared from estrone.

Chromatography, High Pressure Liquid↗

PubMedDate not supplied

The effects of natural flavonoids on lipoxygenase-mediated oxidation of compounds with a benzene ring structure--a new possible mechanism of flavonoid anti-chemical carcinogenesis and other toxicities.

Numerous studies have strongly suggested that flavonoids exhibit antimutagenic, anticarcinogenic, antiallergic, and anti-inflammatory properties, but the mechanism is still far from clear. In this study, the effect of natural flavonoid compounds, such as green tea polyphenol, epigallocatechin gallate, quercetin, and rutin on lipoxygenase-mediated co-oxidation of guaiacol, benzidine, paraphenylenediamine, and dimethoxybenzidine was investigated. Green tea polyphenol, epigallocatechin gallate, quercetin, and rutin can reduce the co-oxidation reaction speed of tested compounds mediated by soybean lipoxygenase and the production of oxidative products and free radical intermediates. Their median inhibition concentrations on guaiacol oxidation mediated by soybean lipoxygenase were 8.22 mg.L-1, 17.8 micromol.L-1, 41.5 micromol.L-1, and 46.3 micromol.L-1, respectively. These were all significantly lower than glutathione, dithiothreitol, butylated hydroxyanisole and gossypol. The data collected in this study suggest that flavonoids may have an anticarcinogenicity and antitoxicity effect through inhibition of oxidative activation.

Anticarcinogenic Agents↗