Riboflavin as an independent and accurate biomarker for adherence in a randomized double-blind and placebo-controlled clinical trial.

BACKGROUND: Medication adherence is critical for success of clinical trials. OBJECTIVE: To assess oral riboflavin is an adherence marker. METHODS: Riboflavin was incorporated into active treatment and placebo pills for a clinical trial lasting for 2 years. RESULTS: The accuracy (area under the receiver operating curve) of urinary riboflavin was 0.91 as a binary classifier of adherence, and was similar or better than for two active study ingredients daidzein (0.92) and genistein (0.87) (all p < 0.0001). Decreased adherence over time was similar in the two study groups. CONCLUSION: Riboflavin is an accurate and useful biomarker for study pill ingestion.

Harderoporphyria: Case of lifelong photosensitivity associated with compound heterozygous coproporphyrinogen oxidase (CPOX) mutations.

A 78-year-old man with a history of neonatal anemia and jaundice and life-long photosensitivity was found to have harderoporphyria, as evidenced by increased porphyrins in urine, plasma, erythrocytes and feces including large amounts of harderoporphyrin in feces and erythrocytes. Two previously undescribed coproporphyrinogen oxidase (CPOX) mutations were identified, including a deletion of four amino acids in a region of the enzyme mutated in 7 of the 8 previously reported cases. This case increases the molecular heterogeneity of this rare porphyria, and illustrates that it should be considered as a cause of chronic photosensitivity and porphyrin elevation at any age.

Zinc deficiency in Mexican American children: influence of zinc and other micronutrients on T cells, cytokines, and antiinflammatory plasma proteins.

BACKGROUND: The Third National Health and Nutrition Examination Survey suggested some Mexican American children are at risk of zinc deficiency. OBJECTIVE: We measured the effects of zinc and micronutrients or of micronutrients alone on indexes of cell-mediated immunity and antiinflammatory plasma proteins. DESIGN: Subjects (n = 54) aged 6-7 y were randomly assigned and treated in double-blind fashion in equal numbers with 20 mg Zn (as sulfate) and micronutrients or with micronutrients alone 5 d/wk for 10 wk. RESULTS: Before treatment the mean +/- SD plasma zinc was 14.9 +/- 1.7 micromol/dL and the range was within the reference; hair zinc was 1.78 +/- 0.52 micromol/g and 41.6% were < or =1.68 micromol/g; serum ferritin was 25.7 +/- 18.6 microg/L and 50.0% were < or =20 microg/L. The zinc and micronutrients treatment increased the lymphocyte ratios of CD4(+) to CD8(+) and of CD4(+)CD45RA(+) to CD4(+)CD45RO(+), increased the ex vivo generation of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma), decreased the generation of interleukin-10 (IL-10), and increased plasma interleukin-1 receptor antagonist (sIL-1ra) and soluble tumor necrosis factor receptor 1 (sTNF-R1). Micronutrients alone increased the ratio of CD4(+) to CD8(+) but not of CD4(+)CD45RA(+) to CD4(+)CD45RO(+), increased IFN-gamma but had no effect on IL-2 or IL-10, and increased sIL-1ra but not sTNF-R1. Efficacy of zinc and micronutrients was greater than micronutrients alone for all indexes except the ratio of CD4(+) to CD8(+), which was affected similarly. CONCLUSIONS: Before treatment, concentrations of hair zinc in 41.6% of subjects and serum ferritin in 50% were consistent with the presence of zinc deficiency. The greater efficacy of the zinc and micronutrients treatment compared with micronutrients alone supports this interpretation.