The similar two-year mortality in the hydralazine-isosorbide dinitrate arms in our previous Vasodilator-Heart Failure Trial (26 percent) and in the present trial (25 percent), as compared with that in the placebo arm in the previous trial, (34 percent) and the further survival benefit with enalapril in the present trial (18 percent) strengthen the conclusion that vasodilator therapy should be included in the standard treatment for heart failure. The different effects of the two regimens (enalapril and hydralazine-isosorbide dinitrate) on mortality and physiologic end points suggest that the profile of effects might be enhanced if the regimens were used in combination.

To determine whether specific antiplatelet therapies improved vein graft patency after coronary artery bypass grafting (CABG) we compared (1) aspirin, 325 mg daily, (2) aspirin, 325 mg three times daily, (3) aspirin plus dipyridamole (325 mg and 75 mg, respectively, three times daily), (4) sulfinpyrazone (267 mg three times daily), and (5) placebo (three times daily). Therapy, except aspirin, was started 48 hr before CABG. When aspirin was a treatment, one 325 mg dose was given 12 hr before surgery and therapy was maintained thereafter according to the assigned regimen. Angiographic graft patency data were obtained within 60 days of surgery. Analysis of early graft patency in 555 patients (1781 grafts), revealed the following graft patency rates: aspirin daily, 93.5%; aspirin three times daily, 92.3%; aspirin and dipyridamole, 91.9%; and sulfinpyrazone, 90.2%. All aspirin-containing therapeutic regimens improved (p<. 05) graft patency compared with placebo (85.2%). Chest tube drainage measured within the first 35 hr after CABG revealed that the median loss with aspirin daily (965 ml), aspirin three times daily (1175 ml), and aspirin plus dipyridamole (1000 ml) exceeded (p<. 02) that with placebo (805 ml), while median loss with sulfinpyrazone (775 ml) did not. The reoperation rate was greater (p < .01) in all the treatment groups that received aspirin (6.5%) compared with the two nonaspirin groups (1.7%). Overall operative mortality was 2.3%, without significant differences among treatment groups. Transient renal insufficiency occurred in 5.3% of patients taking sulfinpyrazone. Thus, early vein graft patency was improved after CABG with all aspirin-containing drug regimens. However, aspirin also increased blood loss and the rate of reoperation after CABG.

To determine whether antiplatelet therapies improve saphenous vein graft patency after coronary artery bypass grafting, we compared 1) aspirin (325 mg once daily), 2) aspirin (325 mg three times daily), 3) aspirin and dipyridamole (325 mg and 75 mg, respectively, three times daily), 4) sulfinpyrazone (267 mg three times daily), and 5) placebo (three times daily). Therapy with dipyridamole and sulfinpyrazone was started 48 hours before bypass graft surgery, and aspirin treatment was begun 12 hours before surgery as a single 325-mg dose. Postoperative treatment was started 6 hours after surgery and continued for 1 year. Graft patency data were obtained early (median, 9 days) and late (median, 367 days) after surgery. The early graft occlusion rate was decreased with all aspirin treatment regimens compared with that of the placebo regimen. At 1 year, in 406 patients with 1,315 grafts, the graft occlusion rate in all of the aspirin groups combined was 15.8% compared with 22.6% for the placebo group (p=0.029). The patients taking aspirin once daily had a lower occlusion rate (13.2%) compared with the patients receiving placebo (p=0.050). At 1 year, in the vein grafts placed to vessels less than or equal to 2.0 mm in diameter (804 distal sites), the graft occlusion rate in all of the aspirin groups was 20.1% compared with 32.3% for the placebo group (p=0.008). In the vein grafts placed to vessels greater than 2.0 mm in diameter (511 distal sites), there was no diference in the occlusion rates between aspirin and the placebo group at 1 year (8.7% vs. 9.0%30, p=0.918).For all grafts shown to be patent in the early study (353 patients with 1,043 grafts), there was no difference in occlusion rates at 1 year when aspirin groups were compared with the placebo group (8.7% vs. 9.4%, p=0.763). Thus, graft patency is improved at 1 year after bypass graft surgery by aspirin, and the major benefit occurred in vein grafts placed to smaller vessels. Our data indicate that if a vein graft is patent early after coronary artery bypass graft surgery, aspirin might not improve the chance that the vein graft will remain open at 1 year. (Circulation 1989;80:1190-1197

Summary 1.Large-scale syntheses of leaf and litter N and P concentrations have demonstrated that leaf and litter N : P ratios both decline with latitude, that litter N : P ratios are generally greater than those of fresh leaves, and that the difference between these two ratios increases towards the tropics. These patterns have been ascribed to either a direct effect of temperature on plant growth rates and leaf-level physiology, or a decline in soil P towards the tropics. We test the hypothesis that global patterns of leaf and litter N : P ratios reflect a soil-P gradient by examining leaf and litter N : P in all species from a temperate rainforest along a soil-P gradient. 2. The soil P gradient followed a toposequence of 20 plots. There was > 50-fold variation in soil total P from ridges (23-136 mg kg -1 ), through faces and terraces (32-744 mg kg -1 ), to gullies (440-1214 mg kg -1 ). 3. The N : P ratios of leaves and litter both declined as soil total P increased, and the N : P ratio of litter was greater than that of fresh leaves. The difference between litter N : P and fresh leaf N : P declined with increasing soil total P supporting the hypothesis that global patterns of N : P ratios reflect gradients of soil P. 4. Compositional turnover with soil P partly contributed to the total plant community leaf and litter nutrient concentration responses. However, consistent within-species responses pointed to a soil-based mechanism for determining responses by the total plant community. 5. Comparisons of our litter data to global data sets suggest that the vegetation was well adapted to low soil nutrient concentrations with 37% of litter N and 24% of litter P samples being below published thresholds for highly proficient nutrient resorption. 6. The range of leaf N and leaf P concentrations at our site captured a large portion of the range reported in global leaf trait data sets. 7. Highly proficient P resorption was responsible for the divergence in leaf and litter N : P ratios on P-poor soils. These results emphasize the significance of proficient nutrient resorption as an advantageous plant trait for nutrient conservation on P-poor soils.

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