Zinc metabolism was studied in 32 normal volunteers after oral (n = 25) or intravenous (n = 7) administration of 65Zn. Data were collected from the blood, urine, feces, whole body, and over the liver and thigh regions for 9 mo while the subjects consumed their regular diets (containing 10 mg Zn ion/day) and for an additional 9 mo while the subjects received an exogenous oral supplement of 100 mg Zn ion/day. Data from each subject were fitted by a compartmental model for zinc metabolism that was developed previously for patients with taste and smell dysfunction. These data from normal subjects were used to determine the absorption, distribution, and excretion of zinc and the mass of zinc in erythrocytes, liver, thigh, and whole body. By use of additional data obtained from the present study, the model was refined further such that a large compartment, which was previously determined to contain 90% of the body zinc, was subdivided into two compartments to represent zinc in muscle and bone. When oral zinc intake was increased 11-fold three new sites of regulation of zinc metabolism were identified in addition to the two sites previously defined in patients with taste and smell dysfunction (absorption of zinc from gut and excretion of zinc in urine). The three new sites are exchange of zinc with erythrocytes, release of zinc by muscle, and secretion of zinc into gut. Regulation at these five sites appears to maintain some tissue concentrations of zinc when dietary zinc increases.

Radioiodine uptake by thyroid remnants and metastases postthyroidectomy for thyroid cancer is increased by withdrawing thyroid hormone, which raises TSH levels. The minimal withdrawal time for maximal uptake is unknown. Therefore, we performed 33 studies in 27 patients after 2 weeks and again after 4 weeks of T3 withdrawal. We examined cervical (or pulmonary) uptake and whole body scanning at 48 h and whole body retention at 48, 72, and 96 h after radioiodine. In 4 studies, only physiological nonthyroidal activity was seen on both scans. Cervical uptake was low in these 4 studies. Of the remaining 29 studies with thyroid activity on both scans, 4 had high cervical uptakes after 2 weeks, which decreased by 4 weeks to less than 50% of the 2 week value. The same trend was seen in whole body retentions. In 2 studies, the uptake increased at 4 weeks compared to that at 2 weeks, but the change was small and was reflected in whole body retention of only 1 of these subjects. In 23 studies, including 6 with metastatic disease, the individual uptakes and whole body retentions were similar after 2 and 4 weeks. The mean uptakes and retentions also did not differ despite significantly higher (P less than 0.001) TSH values at 4 weeks. All definite areas of localization of radioactivity seen on the scans after 4 weeks were seen after 2 weeks. Therefore, radioiodine uptake, scanning, and therapy should be performed after 2 weeks of T3 withdrawal when patients are minimally hypothyroid. Serum TSH should also be measured to identify the rare individual not responding to brief T3 withdrawal.

BACKGROUND.Honest broker services are essential for tissue‐ and data‐based research. The honest broker provides a firewall between clinical and research activities. Clinical information is stripped of Health Insurance Portability and Accountability Act‐denoted personal health identifiers. Research material may have linkage codes, precluding the identification of patients to researchers. The honest broker provides data derived from clinical and research sources. These data are for research use only, and there are rules in place that prohibit reidentification. Very rarely, the institutional review board (IRB) may allow recontact and develop a recontact plan with the honest broker. Certain databases are structured to serve a clinical and research function and incorporate ‘real‐time’ updating of information. This complex process needs resolution of a variety of issues regarding the precise role of the HB and their interaction with data. There also is an obvious need for software solutions to make the task of deidentification easier.METHODS.The University of Pittsburgh has implemented a novel, IRB‐approved mechanism to address honest broker functions to meet the specimen and data needs of researchers. The Tissue Bank stores biologic specimens. The Cancer Registry culls data and annotating information as part of state‐ and federal‐mandated functions and collects data on the clinical progression, treatment, and outcomes of cancer patients. The Cancer Registry also has additional IRB approval to collect data elements only for research purposes. The Clinical Outcomes Group is involved in patient safety and health services research. Radiation Oncology and Medical Oncology provide critical treatment related information. Pathology and Oncology Informatics have designed software tools for querying availability of specimens, extracting data, and deidentifying specimens and annotating data for clinical and translational research. These entities partnered and submitted a joint IRB proposal to create an institutional honest broker facility. The employees of this conglomerate have honest broker agreements with the University of Pittsburgh and the Medical Center. This provides a large group of honest brokers, ensuring availability for projects without any conflict of interest.RESULTS.The honest broker system has been an IRB‐approved institutional entity at the University of Pittsburgh since 2003. The honest broker system currently includes 33 certified honest brokers encompassing the multiple partners of this system. The honest broker system has handled >1600 requests over the past 4 years with a 25% increase in volume each year.CONCLUSIONS.The current results indicate that the collaborative honest broker model described herein is robust and provides a highly functional solution to the specimen and data needs for critical clinical and translational research activities. Cancer 2008. © 2008 American Cancer Society.

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