Biomedical subjects

Hui-Fang Wang

Publications and source records attributed to Hui-Fang Wang.

4 recordsLinked to original sources

PubMed2006

[A new purification methods of small DNAs--the purification methods with silica wool].

The principal purpose of this study is to set up efficient purification techniques of small DNAs which are suitable for isolation of from tens to three hundred bases of genes. On the bases of the technique, purification methods for big DNA fragments are established. In the experiment, the DNA bands were cut after agarose gel electrophoresis and put into 0.5 mL of tubes with silica wool, glass wood, absorbent cotton and cotton at the bottom. And then 10 000 r/min for 2 min, the liquid was collected. The results indicated that silica wool was the best of the materials. The recovery rate for DNAs below 200bp was over 90%, 85% to approximately 90% for 300bp. And the technique can be applied to purify bigger DNA fragments. The kits for DNA purification hardly recovered DNA below 150bp. The recovery rate for 150bp of DNA was 5%, 60% even for 300bp. The efficiencies of enzymic digestion and enzymic connection for the DNAs purified by the technique were the same as those for the DNAs isolated by the kits. So, the technique is obviously superior to kit purification methods.

DNA↗

PubMed2005

Effects of glucose and alpha-tocopherol on low-density lipoprotein oxidation and glycation.

Glycation of blood proteins is considered to be a major contributor to hyperglycemic complications in diabetes mellitus patients. In this study, we demonstrate the efficacy of alpha-tocopherol in reducing low-density lipoprotein (LDL) oxidation and glycation in vitro. Native LDL isolated from healthy subjects was exposed to various concentrations of glucose and malondialdehyde (MDA) with or without alpha-tocopherol enrichment for 7 days in sealed vacuum ampoules. The degree of glycation, copper-induced lag time, content of thiobarbituric acid-reactive substances (TBARS), and alpha-tocopherol levels in LDL were then assessed. LDL lag time was significantly reduced with high levels of glucose and MDA. Alpha-tocopherol enrichment dramatically inhibited the oxidation of LDL in the lag-time assay. However, the length of incubation time was inversely related to the LDL lag time. Longer incubation time resulted in shorter LDL lag time, with or without alpha-tocopherol enrichment. The level of TBARS associated with LDL oxidation was highest in native, MDA-supplemented, and high-glucose samples. The alpha-tocopherol levels were inversely related to glucose levels and incubation times. In conclusion, high-glucose concentrations heightened the oxidative susceptibility of LDL. Alpha-tocopherol enrichment reduced this trend and prevented LDL from undergoing architectural modification.

Glucose↗

PubMed2005

[Immunological mechanism of exfoliative tongue fur in children with asthma].

OBJECTIVE: To explore the immunological mechanism of exfoliative tongue fur in children with asthma. METHODS: Thirty-nine children with asthma, twenty-eight children with repetitive respiratory tract infection (non-asthma) and eleven healthy children were divided into five groups, which were asthma with exfoliative fur or with non-exfoliative fur groups, non-asthma with exfoliative fur or with non-exfoliative fur groups and normal control group. The concentrations of keratin 13 and bcl-2 in cells exfoliated from tongue fur were detected by immunohistochemical method. The expression levels of blood cell chemokine receptor-3 (CCR-3) and CD4(+) were examined by flow cytometry, and the levels of serum cortisol and IgE were detected by radioimmunoassay. RESULTS: The levels of blood CD4(+) and CCR-3 of children with asthma and exfoliative fur were higher than those in the asthma with non-exfoliative fur group and the normal control group (P<0.05). The serum level of cortisol in the groups of asthma with exfoliative fur and non-asthma with exfoliative fur were lower than that in the other groups (P<0.05). The serum levels of IgE in asthma with exfoliative fur or with non-exfoliative fur groups were higher than that in the other groups (P<0.05). Concentrations of keratin 13 in the cells exfoliated from tongue fur in the groups of asthma or non-asthma with exfoliative fur were lower than that of the other groups (P<0.05). There was no significant difference of expression level of bcl-2 in the cells exfoliated from tongue fur among these five groups. CONCLUSION: There is a reasonably close relationship between the formation of exfoliative tongue fur and the immune system such as low level of serum cortisol and high levels of blood CD4(+) and CCR-3, which may all promote the formation of exfoliative fur. The disability of keratinization and apoptosis of epithelial cells of tongue may also be one cause for its formation.

Asthma↗

PubMed2003

Strain rate acceleration yields a better index for evaluating left ventricular contractile function as compared with tissue velocity acceleration during isovolumic contraction time: an in vivo study.

OBJECTIVE: Our study aimed to investigate whether strain rate acceleration (SRA) during isovolumic contraction time (IVCT) could serve as a sensitive indicator of myocardial function. METHODS: A total of 8 sheep underwent occlusion of left anterior descending coronary artery or diagonal branches and 2 sheep underwent left circumflex coronary artery occlusion to create septal, apical, or basal segment myocardial ischemia 19 to 27 weeks before the study. Baseline, volume-loading, dobutamine, and metoprolol infusion were used to produce 4 hemodynamic stages for each sheep. Doppler tissue imaging was acquired using a 5-MHz probe (GE/VingMed Vivid Five, GE Medical Systems, Milwaukee, Wis) on open-chest animals using the liver as a standoff at the apex. Using software (EchoPac, GE Medical Systems), SRA during IVCT was calculated and compared with tissue velocity acceleration (TVA) during IVCT from areas located in the normal and ischemic zones. Also, invasively monitored left ventricle dP/dt was measured as reference contractile function. RESULTS: Both TVA and SRA during IVCT showed higher values for normal tissue than for ischemic area (P <.0001). SRA for normal wall segments changed significantly during the 4 stages (P =.01) with corresponding changes on high-fidelity left ventricular pressure catheters (r = 0.92). TVA over normal segments showed no significant change (P =.29) in the 4 hemodynamic stages. Both TVA and SRA of the ischemic segments showed no significant change with pharmacologic maneuvers or loading conditions. CONCLUSIONS: SRA and TVA during IVCT are both useful indicators for detecting abnormal heart wall motion. However, SRA tends to be more sensitive than TVA for differentiating the response to stress conditions.

Animals↗