Arctic lake physical processes and regimes with implications for winter water availability and management in the National Petroleum Reserve Alaska.

Lakes are dominant landforms in the National Petroleum Reserve Alaska (NPRA) as well as important social and ecological resources. Of recent importance is the management of these freshwater ecosystems because lakes deeper than maximum ice thickness provide an important and often sole source of liquid water for aquatic biota, villages, and industry during winter. To better understand seasonal and annual hydrodynamics in the context of lake morphometry, we analyzed lakes in two adjacent areas where winter water use is expected to increase in the near future because of industrial expansion. Landsat Thematic Mapper and Enhanced Thematic Mapper Plus imagery acquired between 1985 and 2007 were analyzed and compared with climate data to understand interannual variability. Measured changes in lake area extent varied by 0.6% and were significantly correlated to total precipitation in the preceding 12 months (p < 0.05). Using this relation, the modeled lake area extent from 1985 to 2007 showed no long-term trends. In addition, high-resolution aerial photography, bathymetric surveys, water-level monitoring, and lake-ice thickness measurements and growth models were used to better understand seasonal hydrodynamics, surface area-to-volume relations, winter water availability, and more permanent changes related to geomorphic change. Together, these results describe how lakes vary seasonally and annually in two critical areas of the NPRA and provide simple models to help better predict variation in lake-water supply. Our findings suggest that both overestimation and underestimation of actual available winter water volume may occur regularly, and this understanding may help better inform management strategies as future resource use expands in the NPRA.

Balsalazide is superior to mesalamine in the time to improvement of signs and symptoms of acute mild-to-moderate ulcerative colitis.

OBJECTIVE: Balsalazide is a novel azo-bonded 5-aminosalicylic acid treatment for mild-to-moderate ulcerative colitis. The study objective was to compare symptomatic remission rates with balsalazide and mesalamine while controlling for extent of disease and time since diagnosis in patients with active, mild-to-moderate ulcerative colitis. METHODS: A total of 173 patients with sigmoidoscopically verified ulcerative colitis were randomized to 8 wk of double-blind treatment with balsalazide 6.75 g/day or mesalamine 2.4 g/day. Both treatments provided 2.4 g/day of oral 5-aminosalicylic acid. Patients maintained symptom diaries throughout the treatment period. RESULTS: Overall, 46% of balsalazide- and 44% of mesalamine-treated patients achieved symptomatic remission. Higher response rates were noted in newly diagnosed patients with < or = 40 cm of disease (68% vs 61%) than in recently relapsed patients with >40 cm of disease (36% vs 25%). The median time to symptomatic remission was 12 days shorter with balsalazide (25 days) than with mesalamine (37 days). Significantly more balsalazide patients showed sigmoidoscopic (p = 0.002), stool frequency (p = 0.006), rectal bleeding (p = 0.006), and physician's global assessment score (p = 0.013) improvement by 14 days than did mesalamine patients. Similar proportions of patients reported adverse events (54% vs 64%), which were most commonly related to the gastrointestinal and central and peripheral nervous systems. CONCLUSIONS: Balsalazide is an effective and safe treatment for mild-to-moderate ulcerative colitis. Improvement of symptoms occurs considerably earlier with balsalazide than with mesalamine.

Budesonide CIR capsules (once or twice daily divided-dose) in active Crohn's disease: a randomized placebo-controlled study in the United States.

OBJECTIVES: Budesonide controlled ileal release (CIR) capsules deliver budesonide, a glucocorticosteroid with high topical and low systemic activity, to the distal ileum and the proximal colon. In four previous controlled trials in Crohn's disease, remission rates ranged from 51% to 69%. We sought to evaluate the efficacy and safety of this drug in a population of patients in the United States with Crohn's disease. METHODS: In this multicenter, double blind, randomized trial, 200 patients in the United States with mild to moderate Crohn's disease (Crohn's Disease Activity Index [CDAI] between 200 and 450) involving the distal ileum and/or ascending colon received 9 mg of budesonide CIR once daily, 4.5 mg b.i.d., or placebos for 8 wk. The primary outcome was remission defined by a CDAI of 150 or less. RESULTS: Remission was achieved in 48%, 53%, and 33% with 9 mg once daily, 4.5 mg b.i.d., and placebos, respectively, after 8 wk of treatment. Differences between the groups were not significant. The differences in mean change from baseline CDAI between the combined budesonide and placebo groups was significant (p < 0.05). There was no difference in observed adverse events between treatment groups, although a modest decrease in plasma cortisol levels was observed relative to the placebo (p < 0.01). CONCLUSIONS: Treatment of symptomatic Crohn's disease with budesonide CIR capsules (9 mg daily) was safe, and remission rates were similar to those achieved in previous trials. Although the remission rate did not significantly differ from the placebo response in this study, there was a significant change in the mean CDAI from baseline in the combined treatment groups relative to the placebo.