A method exploiting hydroxylapatite chromatography was developed to purify pregnant mare serum gonadotropin (PMSG or eCG) to high biological activity from partially purified commerical preparations. In addition, an alternative method utilizing chromatography on quaternary aminoethyl (QAE)-Sephadex and Sephadex G-200 is also presented. Both procedures are capable of producing, from commerical ma...

The 200,000-dalton neurofilament subunit (P200) and the 160,000-dalton (P160) and 78,000-dalton (P78) neurofilament subunits were partially purified from bovine brain. Intact neurofilaments were prepared by high-speed and sucrose-zone centrifugation. The crude neurofilament was solubilized in 8 M urea solution containing pyridine, formic acid, and 2-mercaptoethanol. The solubilized neurofilamen...

In a previous study, we established camptothecin (CPT)-resistant cell lines, A549/CPT and HT-29/CPT, from human lung cancer A549 and human colon cancer HT-29. A549/CPT was shown to express similar amounts of DNA topoisomerase I (topo I) as the parental line, and HT-29/CPT was shown to express lower amounts of topo I than its parental line. DNA topoisomerases I and II are known to be functionall...