Analysis of products formed during bleomycin-mediated DNA degradation

By the use of DNA, copolymers of defined nucleotide composition, and a synthetic dodecanucleotide having putative bleomycin cleavage sites in proximity to the 5'- and 3'-termini, the products formed concomitant with DNA strand scission have been isolated and subjected to structural identification and quantitation via direct comparison with authentic synthetic samples. The products of DNA strand scission by Fe(II)-bleomycin include oligonucleotides having each of the four possible nucleoside 3'-(phosphoro-2''-O-glycolates) at their 3'-termini, as well as the four possible base propenals. At least for 3-(adenin-9'-yl)propenal and 3-(thymin-1'-yl)propenal, the products formed were exclusively of the trans configuration.

Antithrombin III activity in women with hypertension during pregnancy

Antithrombin III activity was measured prospectively in 127 pregnant women within four weeks of delivery, and the results were tabulated with respect to the clinical diagnosis of their hypertensive disorder. Plasma antithrombin III activity was significantly lower than controls in women with preeclampsia and in women with chronic hypertension and superimposed preeclampsia (P less than .001). In contrast, women with chronic hypertension alone had antithrombin III activities similar to controls. Based on discriminant analysis, an antithrombin III activity of less than 70% was selected as indicative of the preeclampsia-eclampsia syndrome. The sensitivity and specificity of plasma antithrombin III for preeclampsia was 76 and 91%, respectively. Importantly, an antithrombin III activity in excess of 70% accurately predicted the absence of preeclampsia in 89% of study patients. Although gestational ages at delivery were similar in preeclamptic women with antithrombin III activity above and below 70%, women with antithrombin III activity above 70% delivered larger infants and experienced less fetal distress during labor. These findings suggest antithrombin III measurement may be useful in the management of hypertensive pregnant patients who are unresponsive to bedrest.