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A 29-year-old woman was referred to our clinic with abnormal findings on an axial CT scan of the chest. She had initially presented to her primary care physician with intermittent [...]

Background: Pancreatic insufficiency in cystic fibrosis (CF), even with replacement pancreatic enzyme therapy, is often associated with decreased carotenoid absorption. Because the macular pigment of the retina is largely derived from 2 carotenoids, lutein and zeaxanthin, the decreased serum concentrations seen in CF may have consequences for ocular and retinal health Objectives: Our aims were to determine plasma carotenoid concentrations, determine absorption and distribution of macular pigment, and assess retinal health and visual function in CF patients. Design: In 10 adult CF patients (ages 21-47 y) and 10 age- and sex-matched healthy control subjects, we measured macular pigment density in vivo, measured serum lutein and zeaxanthin concentrations, and comprehensively assessed visual performance (including contrast sensitivity, color discrimination, and retinal function) under conditions of daylight illumination. Results: Serum lutein and zeaxanthin were significantly reduced (P < 0.005) in CF patients ([chi square] [+ or -] SD: 87 [+ or -] 36.1 and 27 [+ or -] 15.8 nmol/L, respectively) compared with control subjects (190 [+ or -] 72.1 and 75 [+ or -] 23.6 nmol/L, respectively). Although macular pigment optical density was significantly lower (P < 0.0001) in the CF group (0.24 [+ or -] 0.11) than in the control group (0.53 [+ or -] 0.12), no significant differences in visual function were observed. Conclusions: Adults with CF have dramatically low serum and macular concentrations of carotenoids (lutein and zeaxanthin), but their ocular status and visual function are surprisingly good. The clinical implications of low plasma concentrations of carotenoids in CF are yet to be clarified. KEY WORDS Carotenoids, cystic fibrosis, lutein, zeaxanthin, macular pigment, color vision, contrast sensitivity, electroretinogram

Mansoor, Jim K., Brian M. Morrissey, William F. Walby, Ken Y. Yoneda, Maya Juarez, Radhika Kajekar, John W. Severinghaus, Marlowe W. Eldridge, and Edward S. Schelegle. L-Arginine supplementation enhances exhaled NO, breath condensate VEGF, and headache at 4342 m. High Alt. Med. Biol. 6:289–300, 2005.—We examined the effect of dietary supplementation with L-arginine on breath condensate VEGF, exhaled nitric oxide (NO), plasma erythropoietin, symptoms of acute mountain sickness, and respiratory related sensations at 4342 m through the course of 24 h in seven healthy male subjects. Serum L-arginine levels increased in treated subjects at time 0, 8, and 24 h compared with placebo, indicating the effectiveness of our treatment. L-arginine had no significant effect on overall Lake Louise scores compared with placebo. However, there was a significant increase in headache within the L-arginine treatment group at 12 h compared with time 0, a change not seen in the placebo condition between these two time points. There was a trend (p = 0.087) toward greater exhaled NO and significant increases in breath condensate VEGF with L-arginine treatment, but no L-arginine effect on serum EPO. These results suggest that L-arginine supplementation increases HIF-1 stabilization in the lung, possibly through a NOdependent pathway. In total, our observations indicate that L-arginine supplementation is not beneficial in the prophylactic treatment of AMS.