Glycyrrhetinic acid food supplementation lowers serum potassium concentration in chronic hemodialysis patients

Hyperkalemia is a common life-threatening problem in hemodialysis patients. Because glycyrrhetinic acid (GA) inhibits the enzyme 11beta-hydroxy-steroid dehydrogenase II and thereby increases cortisol availability to the colonic mineralocorticoid receptor, it has the potential to lower serum potassium concentrations. To test this, 10 patients in a 6 month prospective, double-blind, placebo-controlled crossover study were given cookies or bread rolls supplemented with glycyrrhetinic acid or placebo. Twenty-four-hour blood pressure measurements were performed at baseline and week 6 and 12 of each treatment period. The ratio of plasma cortisol/cortisone was significantly increased in all patients on GA as compared to baseline or placebo, indicating appropriate enzyme inhibition. Nine of the 10 patients had a persistent decrease in predialysis serum potassium concentration. On GA, mean predialysis serum potassium was significantly lower than at baseline or on placebo. On placebo, serum potassium was significantly elevated above the upper limit of normal in 76% compared to 30% of measurements during GA treatment. Furthermore, on this treatment the frequency of severe hyperkalemia significantly decreased from 9% to 0.6%. No differences were found in parameters reflecting sodium retention. Although these studies show that prolonged GA supplementation persistently lowers serum potassium in dialysis patients, a long-term toxicity study will be mandatory before we recommend the routine use of this treatment.

An Architecture for End-User TV Content Enrichment

This paper proposes an extension to the televisionwatching paradigm that permits an end-user to enrich broadcast content. Examples of this enriched content are: virtual edits that allow the order of presentation within the content to be changed or that allow the content to be subsetted; conditional text, graphic or video objects that can be placed to appear within content and triggered by viewer interaction; additional navigation links that can be added to structure how other users view the base content object. The enriched content can be viewed directly within the context of the TV viewing experience. It may also be shared with other users within a distributed peer group. Our architecture is based on a model that allows the original content to remain unaltered, and which respects DRM restrictions on content reuse. The fundamental approach we use is to define an intermediate content enhancement layer that is based on the W3C’s SMIL language. Using a pen-based enhancement interface, end-users can manipulate content that is saved in a home PDR setting. This paper describes our architecture and it provides several examples of how our system handles content enhancement. We also describe a reference implementation for creating and viewing enhancements.

Early troponin T and prediction of potentially correctable in-hospital complications after coronary artery bypass grafting surgery

BACKGROUND Peak levels of troponin T (TnT) reliably predict morbidity and mortality after cardiac surgery. However, the therapeutic window to manage CABG-related in-hospital complications may close before the peak is reached. We investigated whether early TnT levels correlate as well with complications after coronary artery bypass grafting (CABG) surgery. METHODS A 12 month consecutive series of patients undergoing elective isolated CABG procedures (mini-extra-corporeal circuit, Cardioplegic arrest) was analyzed. Logistic regression modeling was used to investigate whether TnT levels 6 to 8 hours after surgery were independently associated with in-hospital complications (either post-operative myocardial infarction, stroke, new-onset renal insufficiency, intensive care unit (ICU) readmission, prolonged ICU stay (>48 hours), prolonged need for vasopressors (>24 hours), resuscitation or death). RESULTS A total of 290 patients, including 36 patients with complications, was analyzed. Early TnT levels (odds ratio (OR): 6.8, 95% confidence interval (CI): 2.2-21.4, P=.001), logistic EuroSCORE (OR: 1.2, 95%CI: 1.0-1.3, P=.007) and the need for vasopressors during the first 6 postoperative hours (OR: 2.7, 95%CI: 1.0-7.1, P=.05) were independently associated with the risk of complications. With consideration of vasopressor use during the first 6 postoperative hours, the sum of specificity (0.958) and sensitivity (0.417) of TnT for subsequent complications was highest at a TnT cut-off value of 0.8 ng/mL. CONCLUSION Early TnT levels may be useful to guide ICU management of CABG patients. They predict clinically relevant complications within a potential therapeutic window, particularly in patients requiring vasopressors during the first postoperative hours, although with only moderate sensitivity.