Weight reduction, either by dietary or surgical means, is associated with prolongation of the heart rate corrected QT interval (QTc=QT/R-R'*~) and, on occasion, sudden death. Screening subjects with obesity before weight loss for prolonged QTc intervals is an accepted practice, although at present, there are no guidelines for whether subjects should be fasting before electrocardiogram (EKG) evaluation. The aim of this study was to test the hypothesis that EKG QTc interval duration is independent of meal ingestion. The hypothesis was tested in 11 healthy subjects who ingested a 500-kcal formula meal. A small decrease in absolute QT interval and a steady decline in R-R interval were observed for up to 60 minutes after formula ingestion. The QTc interval increased above baseline at 15 minutes (p<0.007) after meal, a change that persisted for the 1-hour postmeal observation period. Spectral analysis of EKG R-R intervals (low-/high-frequency amplitude ratio) indicated a change in cardiac autonomic flow after meal ingestion. The QTc interval did not lengthen and R-R low-highfrequency amplitude ratio remained unchanged in eight subjects evaluated in a similar manner but in whom isovolumic amounts of water replaced the meal. These observations suggest that (1) cardiac repolarization changes with fasting and feeding, (2) the QTc interval is influenced by meal intake, and (3) the autonomic ner-GALLAGHER, ANGEL0 PIETROBELLI, ADRI- vous system may play a role in meal-related QTc changes. These findings have implications for the evaluation of patients with obesity before starting and during weight loss treatment.

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Yellow nail syndrome (YNS) is characterized by the triad of nail changes, lymphedema and respiratory tract involvement. Several hypotheses have been postulated to explain the findings in YNS including lymphatic drainage abnormalities along with microvasculopathy. The most recent hypothesis, proposed by Berglund and Calmark [Biol Trace Elem Res 2011;143:1-7], suggests a role of titanium dioxide in the development of YNS. This study showed elevated titanium levels (ranging from 1.1 to 170 μg/g of nail plate) in nail clippings or pieces of shed nail from 30 patients with YNS. Titanium was not found in the nails of healthy patients. Complete resolution was seen in 4 patients after removal of their titanium implants. Titanium dioxide is commonly found in cosmetics, sunscreens, medications, confectionaries and joint implants. Exposure to titanium can lead to its ions being released by galvanic action of dental gold or amalgam through the oxidative stress of fluorides. It is hypothesized that this galvanic interaction may lead to the yellow discoloration. At this point, cause and effect is speculative, but titanium may play a role in a subgroup of patients with YNS.

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