suMMARY An ELISA method was developed for the measurement of toxoplasma IgG antibodies in human serum using antigen-coated polystyrene beads as a solid phase and anti human IgG-horse radish peroxidase conjugate as an enzymatic tracer. In order to assess ELISA sensitivity and specificity, a between methods comparison was made using 'conventional' serological tests as reference (dye-test, crossover-linked immunoassay, passive haemagglutination, indirect immunofluorescence). From an analysis of the group classifications obtained some considerations emerged: the ELISA specificity looks comparable with that of the 'reference' tests, as no sample classified as negative by all these tests was ELISA-positive, and vice versa; ELISA appears to correlate better with haemagglutination and immunofluorescence, on the basis of the respective class frequencies; in particular, the number of positives, which is much lower for the dye-test and crossover-linked immunoassay, suggests that a higher sensitivity is reached in the former cases.None of the several tests mostly used for the serodiagnosis of toxoplasmosis appears fully adequate for mass-screening purposes as far as analytical reliability, experimental ease, and promptness of response are concerned. As a matter of fact some of them need special equipment not widely available, and others cannot be used as single tests owing to the incompleteness of the information obtainable and the poor correlation with the clinical situation.Recently, the enzyme-linked immunosorbent assay (ELISA) has been proposed as a promising serological test for infective and infestive diseases. '-5 Also in our laboratories attempts were made to evaluate the actual potential of ELISA in the diagnosis of toxoplasma infections. In particular, this study was aimed at defining the specificity and sensitivity of an ELISA method we have recently developed through a comparison with other serological tests assumed as references, such as the dyetest, crossover-linked immunoassay, indirect haemagglutination, and indirect immunofluorescence.
ABSTRACT18-'4ClBenzylaminopurine (BA) translocation was studied in whole plants of Phaseolus vulgaris L. under three different light regimes (continuous light, 8-hour light + 16-hour dark, dark). Applications were made to the apex, to a cotyledonary leaf, or to the root system. Results showed that no BA basipetal translocation occurred, however BA is easily absorbed by the root system and is translocated acropetally.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.