Declining ambient water phosphorus concentrations in Massachusetts' rivers from 1999 to 2013: Environmental protection works

Over the last century, nutrient concentrations in streams, rivers, lakes and ponds have increased substantially in the United States. Elevated phosphorus levels are a concern due to their ability to cause changes in freshwater ecosystems that are detrimental to humans and wildlife. In the present study, long-term trends in total phosphorus (TP) concentrations from 20 rivers in central Massachusetts from 1999 to 2013 were investigated. Kendall's correlation coefficients were used to demonstrate that 18 of the 20 rivers had significant reductions in TP concentrations (P < 0.05). A similar trend was found when flow-adjusted TP concentrations were analyzed. At the beginning of monitoring activities, the average TP concentration in 9 of the 20 rivers was greater than 0.05 mg/L and 6 of these 9 rivers contained TP concentrations greater than 0.1 mg/L; about fifteen years later, only 3 rivers contained TP greater than 0.05 mg/L and none had concentrations> 0.1 mg/L. TP decreases were greater in rivers with more anthropogenic inputs. Principal component analysis (PCA) revealed that the decline of TP in these Massachusetts streams is likely the result of advancements in wastewater treatment and implementation of effective non-point source management practices.

Bivalirudin versus heparin during coronary angioplasty for unstable or postinfarction angina: Final report reanalysis of the Bivalirudin Angioplasty Study

BACKGROUND

This study was a reanalysis of the Bivalirudin Angioplasty Study, which compared bivalirudin with high-dose heparin during coronary angioplasty for unstable angina.

METHODS

Differences in rates of death, myocardial infarction, or repeat revascularization were compared at 7, 90, and 180 days after angioplasty with intention-to-treat analysis.

RESULTS

The combined end point occurred in 135 of 2161 patients (6.2%) in the bivalirudin group and in 169 of 2151 patients (7.9%) in the heparin group at 7 days (P =.039). Differences persisted between the groups at 90 days (P =.012) and 180 days (P =.153). Bleeding occurred in 76 patients (3.5%) in the bivalirudin group versus 199 (9.3%) in the heparin group (P <.001).

CONCLUSIONS

This analysis supports the hypothesis that bivalirudin reduces ischemic complications and bleeding after angioplasty. Further trials are needed to evaluate bivalirudin versus heparin in conjunction with platelet-glycoprotein IIb/IIIa inhibitors and for coronary stenting.