Development of a high-sensitivity latex reagent for the detection of C-reactive protein.

Various convenient and high-sensitivity immunoassays based on luminescent oxygen channeling and chromatographic techniques have been developed in recent years. This study focused on the latex agglutination immunoassay because it is a simple, homogenous immunoassay, which is also cost effective. We developed a highly sensitive latex reagent and examined the method of antibody conjugation on the latex particle surface. We introduced spacer amino acids in the latex surface to investigate the relationship between the amino acid spacer and the binding of an anti-C-reactive protein (anti-CRP) antibody as well as to investigate the resulting reactivity of the latex reagent to antigen. Because the distance between the latex particle and the antibody is equal in each case, differences in immunoreactivity are attributed to the structure of the amino acid side chain (R). Thus, reactivity of the latex reagent depends on the inorganicity and organicity of R. We suggest that a useful amino acid spacer has an inorganicity-to-organicity ratio of approximately 2.

Development of a highly sensitive latex reagent directed against C-reactive protein (CRP) using epitope analysis with monoclonal antibodies.

C-Reactive protein (CRP) is an acute-phase protein that increases during systemic inflammation and is currently one of the most frequently studied inflammatory markers in epidemiology. We have determined CRP concentration using novel latex reagent with polyclonal antibody. In the present study, we determined the concentration of CRP using monoclonal antibodies, and evaluated the interaction of antigen-antibody reactive sites and latex agglutination to detect low CRP concentrations. We developed four novel monoclonal antibodies that we classified into two major groups, and that were used to prepare the latex reagents. The latex reagents prepared using a cocktail of monoclonal antibodies for different epitopes appeared highly sensitive. The lower limit of CRP detection, which was defined using the mean 3 SD method, was calculated to be 5 ng/ml for the latex reagents when oligoclonal antibodies were utilized. Furthermore, the latex reagents were found to react specifically with CRP in clinical samples.

Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome accompanied by Parkinson's disease.

We encountered two cases of RS3PE (remitting seronegative symmetrical synovitis with pitting edema) syndrome accompanied by Parkinson's disease (PD). Although the etiology of RS3PE syndrome is still unknown, several possible associations, such as malignancies and viral infections, have been reported; RS3PE syndrome is thought to be an autoimmune-mediated disorder. The present patients did not have any factors which are reported to be associated with RS3PE. Whether or not the complication of PD and RS3PE syndrome is incidental needs to be further examined, and we discuss here the possible cause of association between PD and RS3PE syndrome, including dopamine agonists one of the anti-PD medications.

Chlorine isotope fractionation during reductive dechlorination of chlorinated ethenes by anaerobic bacteria.

Chlorine isotope fractionation during reductive dechlorination of trichloroethene (TCE) and tetrachloroethene (PCE) to cis-1,2-dichloroethene (cDCE) by anaerobic bacteria was investigated. The changes in the 37Cl/35Cl ratio observed during the one-step reaction (TCE to cDCE) can be explained by the regioselective elimination of chlorine accompanied by the Rayleigh fractionation. The fractionation factors (alpha) of the TCE dechlorination by three kinds of anaerobic cultures were approximately 0.994-0.995 at 30 degrees C. The enrichment of 37Cl in the organic chlorine during the two-step reaction (PCE to cDCE) can be explained by the random elimination of one chlorine atom in the PCE molecule followed by the regioselective elimination of one chlorine atom in the TCE molecule. The fractionation factors for the first step of the PCE dechlorination with three kinds of anaerobic cultures were estimated to be 0.987-0.991 at 30 degrees C using a mathematical model. Isotope fractionation during the first step would be the primary factor for the chlorine isotope fractionation during the PCE dechorination to cDCE. The developed models can be utilized to evaluate the fractionation factors of regioselective and multistep reactions.