Comparison of Efficacy and Safety of Non-Regenerated and Regenerated Oxidized Cellulose Based Fibrous Haemostats.

PURPOSE: Various forms of local haemostats are increasingly used routinely in surgical procedures. Our work is the first comparison of the efficacy and safety of non-regenerated and regenerated oxidized cellulose based fibrous haemostats. METHODS: The haemostatic efficacy and safety of fibrous haemostats based on ONRC and ORC were compared in a randomized multicenter study. The primary endpoint was successful haemostasis within 3 minutes of application and no need for surgical revision within 12 hours after the procedure for recurrent bleeding. RESULTS: There was a significant difference in the rate of successful haemostasis in 3 minutes that was achieved in 82% and 55% in the ONRC and ORC groups, respectively (confidence interval 99%; p = 0.009). Mean time to haemostasis was 133.9 ± 53.95 seconds and 178.0 ± 82.33 seconds, in the ONRC, and ORC group, respectively (p = 0.002). Revision surgery for re-bleeding was necessary in 0 (0%), and 1 (2%) of patients in the ONRC, and ORC group, respectively. No adverse events were reported. CONCLUSION: Fibrous haemostat based on ONRC was non-inferior compared to fibrous haemostat based on ORC when used in accordance with its intended purpose, and was safe and efficient.

Large seasonal swings in leaf area of Amazon rainforests.

Despite early speculation to the contrary, all tropical forests studied to date display seasonal variations in the presence of new leaves, flowers, and fruits. Past studies were focused on the timing of phenological events and their cues but not on the accompanying changes in leaf area that regulate vegetation-atmosphere exchanges of energy, momentum, and mass. Here we report, from analysis of 5 years of recent satellite data, seasonal swings in green leaf area of approximately 25% in a majority of the Amazon rainforests. This seasonal cycle is timed to the seasonality of solar radiation in a manner that is suggestive of anticipatory and opportunistic patterns of net leaf flushing during the early to mid part of the light-rich dry season and net leaf abscission during the cloudy wet season. These seasonal swings in leaf area may be critical to initiation of the transition from dry to wet season, seasonal carbon balance between photosynthetic gains and respiratory losses, and litterfall nutrient cycling in moist tropical forests.