Biomedical subjects

Masahide Kawamura

Publications and source records attributed to Masahide Kawamura.

5 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↗

PubMed2003

[Entrapment neuropathy of the tibial nerve by a Baker's cyst: case report].

Entrapment neuropathies of the tibial nerve by Baker's cysts occur infrequently. We present a patient with entrapment neuropathy of the tibial nerve by a Baker's cyst which is preoperatively evaluated by nerve conduction study and magnetic resonance imaging. We present this case with a review of the literatures.

Female↗

PubMed2002

The effects of affinity-purified anti-DNA antibodies from patients with systemic lupus erythematosus on the fluorescent antinuclear antibody assay using HEp-2 cells.

The aim of this study was to clarify the effects of anti-dsDNA antibodies on the titer and the nuclear staining pattern(s) in a fluorescent antinuclear antibody (FANA) assay using HEp-2 cells. Anti-dsDNA derived from 14 patients with systemic lupus erythematosus (SLE) was individually affinity-purified. The anti-dsDNA titer of the purified anti-dsDNA solution was measured by radioimmunoassay (RIA) or by enzyme-linked immunosorbent assay (ELISA). In the FANA assay, the anti-dsDNA solution was diluted in a stepwise manner and its titer was expressed by the endpoint dilution. The nuclear staining pattern in the anti-dsDNA solution was examined at the 1:5 and 1:20 dilutions and at the endpoint dilution. The anti-dsDNA titers of the affinity-purified anti-dsDNA solution were high enough (13 to 126 IU/ml) to be measured by RIA. However, the antinuclear antibody (ANA) titers of this solution were relatively low: 1:20 to 1:320. In the study of nuclear staining the peripheral pattern was observed in nine of the 14 cases at a 1:5 dilution. However, at the endpoint dilution, all cases exhibited the homogeneous pattern. These findings indicate that in the FANA assay using HEp-2 cells, 1) although serum samples show high anti-dsDNA titers by RIA or by ELISA, the antibodies' direct contribution to ANA titers is limited, and 2) when samples reveal a homogeneous staining pattern at the endpoint dilution, this suggests the presence of anti-dsDNA.

Adsorption↗

PubMedDate not supplied

Efficacy of tear eosinophil cationic protein level measurement using filter paper for diagnosing allergic conjunctival disorders.

PURPOSE: We investigated the efficacy of the tear sampling method using a filter paper to evaluate eosinophil cationic protein (ECP) levels in patients with allergic disorders. METHODS: Subjects were an allergic group comprising patients with allergic conjunctivitis, vernal keratoconjunctivitis, or atopic keratoconjunctivitis, a Sjögren group comprising patients with secondary Sjögren syndrome, and a control group comprising healthy volunteers. Tears were sampled using the Schirmer Method I and the sample was eluted from the filter paper in 50 microL of elution solution containing phosphate buffer solution with 0.5 M NaCl + 0.1% Tween 20. Then the ECP concentration in the elution sample was determined by the enzyme-linked immunosorbent assay method. RESULTS: Tear ECP level in the allergic group was significantly higher than the levels in the other two groups (P <.01 for the Sjögren group and P <.001 for the control). Furthermore, the tear ECP level of each allergic disease subgroup in the allergic group was significantly higher than that in the control group. CONCLUSIONS: This method of determining tear ECP concentration is useful not only to diagnose allergic conjunctival disorders but also to evaluate their clinical stages.

Adolescent↗

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↗