High-order spin diffusion mechanisms in (19)F 2-D NMR of oxyfluorides.

Negative cross-peaks have been observed in the (19)F 2-D magnetization-exchange MAS NMR spectra of Ba(2)MoO(3)F(4) under fast-spinning conditions. The polarization transfer dynamics are studied as a function of the spinning frequency and the frequency separation of the resonances. The results are consistent with a novel mechanism, in which four spins simultaneously exchange Zeeman magnetization with each other, in an energy-conserving process.

Defibrase, a purified fibrinolytic protease from snake venom in acute myocardial infarction.

To investigate the thrombolytic effects of defibrase in AMI, 157 pts with AMI were studied. Of the 157 pts, 87 were assigned to defibrase thrombolysis and 70 to the conventional therapy plus heparin (control). Coronary arteriography was performed in 36 pts of the defibrase group and 26 of the control group. Pretreatment coronary arteriography was performed in 10 pts and total occlusion of infarct-related artery (IRA) was demonstrated in 7. Thirty to 45 min after either intracoronary or intravenous defibrase thrombolysis, recanalization occurred in 4 of the 7 pts. The perfusion and stenosis was improved in 2 of the 3 pts with patent IRA. Of the 10 pts who underwent emergency coronary arteriography after the onset of i.v. defibrase thrombolysis, 6 were shown to have patent IRAs. Of the 16 pts who underwent coronary arteriography two weeks after the i.v. defibrase thrombolysis, 13 were shown to have patent IRAs. In contrast, only 11 of the 26 pts in the control group had patent IRAs two weeks after admission to the hospital. Of the 36 angiographic cases of the defibrase group, 15 underwent follow-up coronary arteriography, only 1 pt showed reocclusion. In comparison to the control group, the pts in the defibrase group had earlier CPK peaking, higher percentage of pts with LVEF > 0.5, a lower mortality and complication rate. Major spontaneous bleeding complications were rarely seen with defibrase. The results indicate that defibrase is an effective thrombolytic agent with a reasonable recanalization rate, low reocclusion rate and a low rate of bleeding complications.