In the article “Comparison Between Adenoviral and Retroviral Vectors for the Transduction of the Thymidine Kinase PET Reporter Gene in Rat Mesenchymal Stem Cells,” by Roelants et al. (J Nucl Med. 2008;49:1836–1844), the abstract incorrectly states that mesenchymal stem cells either were incubated in advance with 9-(4-18F-fluoro-3-[hydroxymethyl]butyl)guanine (18F-FHBG) or were administered after an intravenous injection of 18F-FHBG. In fact, either the cells were incubated in advance with 18F-FHBG, or they were administered and 18F-FHBG was thereafter intravenously administered. The authors regret the error.
In the article “Reproducibility of Standardized Uptake Value Measurements Determined by 18F-FDG PET in Malignant Tumors,” by Nahmias and Wahl (J Nucl Med. 2008;49:1804–1808), 2 acknowledgments were omitted. The study was supported in part by grant R33 CA94317 from the National Institutes of Health, and research technologist Misty Long acquired all study data. The authors regret the omissions.