Biomedical subjects

Shinsuke Arao

Publications and source records attributed to Shinsuke Arao.

3 recordsLinked to original sources

PubMed2003

A highly sensitive quantitative immunochromatography assay for antigen-specific IgE.

We have developed a highly sensitive quantitative enzyme immunochromatography system for antigen-specific IgE, which is clinically important for the diagnosis of allergic diseases. The system uses alkaline phosphatase-labeled anti-IgE antibody (ALP-anti-IgE) and immobilized target antigen, for example cedar pollen antigen, on a membrane. Antigen-specific IgE present in the serum binds the immobilized antigen after complexing with the ALP-anti-IgE. Subsequently, the enzyme substrate migrates to the complex on the antigen line, which is stained blue. The intensity of the staining was analyzed by a quantitative detector, but can also be assessed directly by the naked eye. This system was able to detect 0.2 U/ml of IgE specific for Japanese cedar pollen. The results correlated well (Spearman's rank correlation coefficient, 0.95) to those in AlaSTAT system, which is a reliable enzyme-linked immunosorbent assay (ELISA) method. This antigen-specific IgE assay system is suitable for point-of-care testing.

Allergens↗

PubMed2002

Flame photometric detector for thin-layer chromatography.

A new flame photometric detector for thin-layer chromatography (TLC) was studied to determine sulfur and phosphorus containing compounds in materials with a high boiling point. The detector was integrated with a flame ionization detector into the Iatroscan TLC-flame ionization detection analyzer. The principle of the detector is based on the photometric detection of flame emission of heteroatom in a hydrogen-air flame. The emission spectra of sulfur and phosphorus were measured using dibenzothiophene (DT) and phosphoric acid as source materials. Interference filters of 394 and 526 nm were chosen for spectral isolation of the sulfur and phosphorus emissions. The effects of variation in air flow-rate and scan speed as related to both sulfur and phosphorus compounds were studied in order to define optimum detection conditions. The best result for the detection of DT as a sulfur compound was obtained under combined hydrogen and air flow-rates of 160 and 500 ml/min, respectively, with a scan speed of 30 s/rod. The response to DT was linear in the range of 0.25-4 microg. On the other hand, the most suitable conditions for detecting phosphatidylcholine (PC) as a phosphorus compound were combined hydrogen and air flow-rates of 160 and 1500 ml/min, respectively, with a scan speed of 40 s/rod. The response to PC was linear in the range of 0.25-16 microg. Application of the instrument with selective detection of sulfur and phosphorus compounds was demonstrated using heavy oils and human serum lipids.

Chromatography, Thin Layer↗

PubMedDate not supplied

Quantitative analysis of antigen specific IgE in tears in comparison to serum samples.

We determined pollen specific IgE in tears and compared these results to the concentration of specific IgE in serum samples. We obtained tears (using Schirmer strips) and serum samples from subjects with Japanese cedar (Cryptomeria japonica) pollinosis, and tested for C. japonica pollen specific IgE using a quantitative ELISA. Time kinetic analyses through the pollen season showed that specific IgE levels in tears were found to increase earlier than those in sera and reached their maximum at the end of or after the pollen season, from March to early June. In the C. japonica pollen free season, July to December, the specific IgE levels in tears decreased, although the serum levels remained relatively high. These results indicate that the quantitative assay for specific IgE in tears might be useful to identify specific eye allergens.

Adult↗