Deacon and Hunter (1962) have shown that the fluorescent treponemal antibody (FTA) test detects two separate antibodies in syphilitic sera. One, a group antibody, reacts with other treponemes, such as the Reiter organism, Treponema microdentium, and Treponema zuelzerae, as well as with Treponema pallidum, presumably because of an antigen shared in common by these organisms. Removal of group ant...

This quotation from John Fowles’s The French Lieutenant’s Woman concludes Ray’s 1980 paper, “A Logic for Default Reasoning,” one of the most influential and widely cited papers in all AI. The quotation captures what was special about Ray: He had an adventurer’s desire to go beyond the boundaries of our current understanding, together with a mathematician’s insistence on precision. Ray the adven...

The Treponemal Immobilization Test (TPI) is now generally accepted as a highly sensitive and specific test for treponemal infection, but its complexity and the difficulties inherent in the use of a living organism as antigen have restricted its performance to specialized laboratories. These limitations have led to the re-investigation of the cultivable strains of treponemes as antigens for the ...

The Treponemal Immobilization Test (TPI) is now generally accepted as a highly sensitive and specific test for treponemal infection, but its complexity and the difficulties inherent in the use of a living organism as antigen have restricted its performance to specialized laboratories. These limitations have led to the re-investigation of the cultivable strains of treponemes as antigens for the ...

TR-b is a Reiter treponeme antigen, cross-reacting with an antigen in Treponema pallidum (Nichols pathogenic strain). Sera from patients with secondary syphilis contain precipitating antibodies against TR-b. The isolation of TR-b from a bacterial sonic extract is described here. It involved five fractionation steps: anion-exchange chromatography (DE-52 Whatman), gel filtration (Ac-A-22 Ultrogel...

Haemagglutination reactions for the diagnosis of syphilis were first reported by Blumenthal (1932) and Bachmann (1932), who used an extract of syphilitic liver as the antigen. However, the test yielded both false positive and false negative reactions, rendering it of no diagnostic value. An agglutination test with suspensions of Reiter treponemes was used for testing cerebrospinal fluid by Roem...