The Bra/Brb alloantigen system on human platelets.

Anti-Bra was first identified in four cases of neonatal alloimmune thrombocytopenia (NAIT). The antigen Bra is localized on the glycoprotein Ia/IIa complex of platelets. Anti-Bra can best be detected by a glycoprotein-specific immunoassay using monoclonal antibodies for antigen immobilization (MAIPA assay) and radioimmunoprecipitation (RIP).

Posttransfusion purpura associated with an anti-Bak.

We describe a 46-year-old white woman with typical clinical features of posttransfusion purpura (PTP) whose serum held a platelet-specific alloantibody reactive with an antigen antithetical to Baka, i.e. anti-Bakb.

A new platelet-specific alloantigen Bra. Report of 4 cases with neonatal alloimmune thrombocytopenia.

Sera obtained from 4 mothers of children with neonatal alloimmune thrombocytopenia contained a platelet-specific alloantibody, anti-Bra, which defined an antigen apparently different from all known platelet alloantigens. All 4 fathers were Bra positive, whereas all mothers were Bra negative. The minimal postnatal values of platelet counts ranged from 19 X 10(9) to 75 X 10(9)/1.

The catch-22's of cost containment.

While exploring the problem of escalation of health care expenditures in urology and analyzing various means to curtail this escalation, we noted a recurrent problem relating to the negative incentives inherent in presently used reimbursement mechanisms. Proposed solutions to a particular problem usually are accompanied by new economic difficulties arising from the solution. A series of Catch-22's are encountered in many different problems concerning economic health care delivery.