Anomalous sedimentation schlieren diagrams of the blood in patients with rheumatic diseases as an indicator of the presence of reversibly dissociating immune complexes

Circulating immune complexes (CIC) are of considerable importance in the pathogenesis of rheumatoid diseases. The study of CIC has so far been restricted to their stable forms. This paper presents the data of ultracentrifugation showing that sera from rheumatoid patients often contain special population of reversibly dissociating CIC. It is noted that antibodies forming such kinds of CIC might either be present in significant excess, as compared to antigens, or possess low affinity.     

Activation of prothrombin, modified by maleic anhydride, some properties of N-maleyl-thrombin with free alpha-amino groups]

Conditions for the acylation of bovine prothrombin by maleic anhydride are worked out. The reaction is shown to modify not more than 95% of amino groups. The changes in hydrodynamic and electrophoretic properties testify about structural changes of prothrombin as a result of the modification of free amino groups. The activation of maleyl-prothrombin to maleyl-thrombin took place in 25% sodium citrate only in the presence of thrombin and the Xa factor. The increase of modified amino groups in prothrombin resulted in the decrease of the activity of generated maleyi-thrombin. The main fraction of maleyl-thrombin with free alpha-amino groups had a sedimentation coefficient of 2.1 S and possessed a residual esterase activity.     

Synthesis of trisaccharide fragment of O-specific polysaccharides of Salmonella of serologic groups C2 and C3 and its conversion into synthetic antigen of a copolymer type

Abequosyl-(alpha 1----3)-L-rhamnopyranosyl-(1----2)-D-mannopyranosides anomeric in the rhamnose residue have been synthesised. 2-Benzyloxycarbonylaminoethyl group used as the aglycon can be transformed into 2-acrylamidoethyl aglycon in the final stages of the syntheses. These isomeric alpha-glycosides were converted into copolymer artificial antigens, which are of interest for studying immunochemistry of factor O:8 of Salmonella O-antigens (serological groups C2 and C3).     

Thioglycoside synthons for obtaining di-, tri- and hexasaccharide fragments of O-specific polysaccharides of Salmonella from serogroups A, B and D1

The synthesis of a versatile trisaccharide synthon is described with the combination of protecting groups suitable for preparing higher oligosaccharides of the sequence Man-Rha-Gal and for introducing side-chain substituents (such as residues of 3,6-dideoxy-hexoses and alpha-D-glucose). This synthon was used for the synthesis of protected tri- and hexasaccharide fragments (as 2-phtalimidoethyl glycosides) of Salmonella polysaccharides (serological groups A, B, and D1).