Biomedical subjects

Yu-Xia Wang

Publications and source records attributed to Yu-Xia Wang.

4 recordsLinked to original sources

PubMed2006

Quality evaluation of Radix Astragali through a simultaneous determination of six major active isoflavonoids and four main saponins by high-performance liquid chromatography coupled with diode array and evaporative light scattering detectors.

A method, high-performance liquid chromatography coupled with diode array and evaporative light scattering detectors (HPLC-DAD-ELSD), was developed to evaluate the quality of Radix Astragali through a simultaneous determination of six major active isoflavonoids and four main saponins. The wavelength at 280 nm was chosen to determine six isoflavonoids: calycosin-7-O-beta-D-glucoside (1), ononin (2), (6alphaR, 11alphaR)-9,10-dimethoxypterocarpan-3-O-beta-D-glucoside (3), (3R)-2'-hydroxy-3',4'-dimethoxyisoflavan-7-O-beta-D-glucoside (4), calycosin (5), and formononetin (6); and ELSD connected after DAD was employed to determine four saponins: astragaloside IV (7), astragaloside II (8), astragaloside I (9), and acetylastragaloside I (10). This assay was fully validated with respect to precision, repeatability and accuracy. The proposed method was successfully applied to quantify the ten components in eleven samples from different localities in China; significant variations were demonstrated in the content of these compounds in the samples from different areas. This simple, rapid, low-cost and reliable HPLC-DAD-ELSD method is suitable for routine quantitative analysis and quality control of traditional Chinese medicines (TCMs) consisting of bioactive multi-components with different structures such as Radix Astragali.

Astragalus Plant↗

PubMed2004

Endoscopic survey of esophageal cancer in a high-risk area of China.

AIM: To characterize the histological types of esophageal and cardiac mucosa by endoscopic survey of a population in a high-risk area of esophageal cancer of China. METHODS: A selected cohort of residents in Cixian County during December 2001 and May 2002 was surveyed by using Lugol's staining, followed by computer-based statistical analysis of the data with SPSS 10.0 software. RESULTS: Histologically, the detection rates of squamous epithelial acanthosis, squamous epithelial atrophy, and basal cell hyperplasia in the esophagus were 1.9% (38/2,013), 0.1% (3/2,013) and 0.9% (18/2,013) respectively, and those of mild, moderate, and severe esophagitis were 34.9% (703/2,013), 1.6% (33/2,013) and 0.2% (2/2,013) respectively. Mild, moderate, and severe esophageal dysplasia were detected in 8.6% (172/2,013), 7.8% (157/2,013) and 2.6% (53/2,013) respectively in the selected population, whereas in situ carcinoma, intramucosal carcinoma, invasive squamous carcinoma of the esophagus in 2.5% (50/2,013), 0.2% (4/2,013) and 0.7% (14/2,013) respectively. The detection rates of non-atrophic gastritis and atrophic gastritis of the cardia were 36.3% (730/2,013) and 11.5% (232/2,013) respectively, with mild and severe dysplasia of the cardia detected in 2.5% (51/2,013) and 0.8% (17/2,013), respectively, in this population; the rates of intramucosal adenocarcinoma and invasive adenocarcinoma of the cardia were 0.1% (3/2,013) and 0.8% (17/2,013) respectively. The detection rate of esophageal cancer at early stage was 79.4% (54/68). The survey rate (ratio of examined population to expected population) was 73.8% (2,013/2,725). CONCLUSION: Histologic types of the esophageal and cardiac mucosa were characterized by endoscopic survey in a high-risk population of esophageal cancer, which may help the early detection and treatment of esophageal and cardiac cancers and dysplasia, and reduce the mortality of such malignancies.

Adult↗

PubMed2004

Cycloartane-type triterpenoids from Sphaerophysa salsula.

Four novel cycloartanes, named sphaerophysone A (1), B (2), C (3) and D (4), were isolated from the ethanol extract of Sphaerophysa salsula (Pall.) DC. The structures were elucidated on the basis of spectral evidence, and the stereochemistry of compound 1 was defined by X-ray crystallographic analysis. Sphaerophysone B (2) may be an artifact formed in the isolation procedure.

Drugs, Chinese Herbal↗

PubMed2003

Molecular simulation of a single-chain antibody against AChE to explore molecular basis of inhibitory effect of 3F3 McAb on enzyme activity.

AIM: To explore the molecular basis of the inhibitory effect of 3F3, a monoclonal antibody against acetylcholinesterase (AChE), by computer-aided molecular simulation. METHODS: The single-chain 3F3 antibody (Sc3F3) was designed by joining VH and VL via a flexible linker (Gly4Ser)3. The amino acid sequence of the recombinant Sc3F3 was then subjected to computer-aided molecular modeling, and docking with the antigen molecule AChE to mimic the immunoactive interaction in a three-dimensional fashion. RESULTS: The modeled structure of Sc3F3 manifested the common features of a classical antibody. Both VH and VL were composed of two ?-sheets and connecting loops. The docking profile of the action between Sc3F3 with AChE demonstrated the formation of a stable structure. The van der Waals force played an important role suggesting that the complex was formed mainly via hydrophobic interactions between Sc3F3 and AChE molecules. CONCLUSION: The spatial structure of the complex of Sc3F3 and AChE showed that Sc3F3 overlaid the entrance of the active center gorge of AChE blocking the access of substrate.

Acetylcholinesterase↗