Biomedical subjects

Woochang Lee

Publications and source records attributed to Woochang Lee.

21 records · Page 2Linked to original sources

PubMed2003

Low-density lipoprotein subclass and its correlating factors in diabetics.

OBJECTIVES: Small dense LDL, low density lipoprotein (LDL) particles with small size and high density, is regarded as a significant risk factor for cardiovascular diseases. Diabetes mellitus is one of the conditions accompanied by increased small dense LDL. We analyzed LDL subclass in type 2 diabetics and normal controls with LipoPrint LDL System to investigate the LDL heterogeneity in diabetics and factors affecting it. DESIGN AND METHODS: We selected 40 normal controls and 40 type 2 diabetics with fasting blood glucose level over 7.0 mmol/L and HbA1c level over 7%. LDL subclass was determined with LipoPrint LDL System. LipoPrint LDL System fractionates LDL into seven parts (LDL1-7) by size and LDL3 to LDL7 are defined as small-sized LDL. In addition we estimated 'the percent of small-sized LDL over whole LDL' and defined it as 'small-sized LDL proportion'. RESULTS: Mean small-sized LDL proportion was significantly higher in diabetics (23.4%) than in controls (11.8%) (p<0.001) and small-sized LDL proportion showed positive correlation with blood levels of glucose, HbA1c, total cholesterol, triglyceride, and oxidized LDL and negative correlation with HDL cholesterol level in univariate analysis (p<0.001). Of these parameters, triglyceride, HbA1c, oxidized LDL were statistically significant variables contributing to the small-sized LDL proportion in stepwise multiple regression analysis. CONCLUSIONS: We analyzed small-sized LDL proportion in type 2 diabetics and found that it was significantly increased in diabetics than control subjects and it was independently correlated with triglyceride, HbA1c, oxidized LDL in descending order, which are reflecting lipid metabolism, glycation, and oxidative stress, respectively.

Adult↗

PubMed2003

Immunosensor for detection of Legionella pneumophila using surface plasmon resonance.

Immunosensor using surface plasmon resonance (SPR) onto self-assembled protein G layer was developed for the detection of Legionella pneumophila. A self-assembled protein G layer on gold (Au) surface was fabricated by adsorbing a mixture of 11-mercaptoundecanoic acid (MUA) and hexanethiol (molar ratio of 1:2) and the activation process for chemical binding between free amine (-NH(2)) of protein G and 11-(MUA) using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDAC) in series. The formation of self-assembled protein G layer on Au substrate and the binding of antibody and antigen in series were confirmed by SPR spectroscopy. The surface morphology analyses of self-assembled protein G layer on Au substrate and monoclonal antibody against L. pneumophila immobilized on protein G were performed by atomic force microscope (AFM). The immunosensor for detection of L. pneumophila using SPR was developed and its detection limit could find up to 10(5) cells/ml.

Biosensing Techniques↗

PubMed2002

The development of systematic quality control method using laboratory information system and unity program.

Quality control (QC) process is performed to detect and correct errors in the laboratory, of which systematic errors are repeated and affect all the laboratory process thereafter. This makes it necessary for all the laboratories to detect and correct errors effectively and efficiently. We developed an on-line quality assurance system for detection and correction of systematic error, and linked it to the Unity Plus/Pro (Bio-Rad Laboratories, Irvine, USA), a commercially available quality management system. The laboratory information system based on the client-server paradigm was developed using NCR3600 (NCR, West Columbia, USA) as the server and database for server was Oracle 7.2 (Oracle, Belmont, USA) and development tool was Powerbuilder (Powersoft Burlignton, UK). Each QC material is registered and gets its own identification number and tested the same way as patient sample. The resulting QC data is entered into the Unity Plus/Pro program by in-house data entering program or by manual input. With the implementation of in-house laboratory information system (LIS) and linking it to Unity Plus/Pro, we could apply Westgard's multi-rule for higher error detection rate, resulting in more systematic and precise quality assurance for laboratory product, as well as complementary to conventional external quality assessment.

Chemistry, Clinical↗