Biomedical subjects

W Zou

Publications and source records attributed to W Zou.

74 records · Page 5Linked to original sources

PubMedDate not supplied

Fat contents of cereal foods: comparison of classical with recently developed extraction techniques.

Eight cereal products ranging from a fat-free ready-to-eat (RTE) cereal (frosted flakes) to a full-fat high-ratio cake mix were subjected to analyte separation by anhydrous diethyl ether extraction (EE), acid hydrolysis/mixed ether extraction (AH), solid-phase extraction (SPE), and supercritical fluid extraction (SFE) with CO2 and with CO2 modified with 15% ethanol (SFEmod). Gravimetric analyses of extracts indicated higher (P < or = 0.05) crude fat values by AH than by EE, SFE, or SFEmod. Extractions followed by fatty acid methyl ester analysis also produced higher (P < or = 0.05) triglyceride means by AH than by other methods used for heat-treated RTE cereals and for ready-to-cook (RTC) cream of wheat. Therefore, for labeling purposes, AH seems most appropriate because in most cases it achieves higher triglyceride values than extraction with solvent(s) alone. SFE and SPE, on the other hand, yield fat values similar to those obtained by EE and offer the advantages of reduced solvent volume, short extraction times, and ease of laboratory automation.

Dietary Fats↗

PubMedDate not supplied

Quantification of cytokine gene expression by competitive PCR using a colorimetric assay.

Competitive reverse transcription-polymerase chain reaction (RT-PCR) is a new technique allowing quantification of cytokine gene expression from either experimental or clinical samples. In this assay, a time-consuming step is the quantification of amplified products. To improve this step, we set up a colorimetric assay in which the amplified product from either the cDNA or the competitor can be reliably quantified. Using this approach, which can be completely automatized, up to 320 PCR products can be quantified each day. In this report, we describe the quantification of IL-10 mRNA molecules as compared to that of beta-actin mRNA molecules. The sensitivity of the quantification was 7.7 x 10(7) molecules for the amplified beta-actin cDNA and the amplified IL-10 cDNA, corresponding to approximately 9.6 pg amplified beta-actin cDNA and 11 pg amplified IL-10 cDNA, respectively. The intra-assay variation coefficient was < 12%. This technique can be readily extended to all cytokines, and it thus allows routine monitoring of cytokine gene expression, either from experimental samples or from clinical trials.

Actins↗