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Results of vitrifying Fernald OU-4 wastes
Three silos in Operable Unit 4 (OU-4) at the Feed Materials Production Center in Fernald, Ohio, contain residues from the processing of pitchblende ores. Silos 1 and 2, designated as K-65, contain the depleted ore with a BentoGrout cap over the material to reduce radon emanation, while Silo 3 contains calcined residue from processing solutions. The residues in the three silos contain radium, uranium, uranium daughters, and heavy metals (primarily lead). Vitrification tests were carried out on various mixtures of the above materials and the resulting glasses were analyzed. The vitrified residues all tested non-hazardous'' by the Toxicity Characteristic Leachate Procedure (TCLP) and demonstrated a high degree of durability by the Product Consistency Test (PCT). The specific gravity and radon emanation of both the vitrified and non-vitrified residue were measured. Volume reductions ranging from 50 to 68 percent were obtained while the radon emanation rate was reduced by a factor of about 500,000. Radon emanation from the vitrified residue is of the same order of magnitude as emanation from natural building materials such as brick or concrete
Changes in serum calcitonin concentrations, incidence of medullary thyroid carcinoma, and impact of routine calcitonin concentration monitoring in the Exenatide study of Cardiovascular Event Lowering (EXSCEL)
OBJECTIVE Increases in serum calcitonin, a tumor marker for medullary thyroid carcinoma (MTC), have been associated with glucagon-like peptide 1 receptor agonist use in some preclinical studies. We report calcitonin changes in exenatide-treated and placebo-administered participants and MTC incidence in the EXenatide Study of Cardiovascular Event Lowering (EXSCEL) and consider the impact of within-trial calcitonin monitoring. RESEARCH DESIGN AND METHODS EXSCEL participants were randomized 1:1 to once-weekly exenatide 2 mg or placebo. Serum calcitonin was measured at baseline (with trial medication discontinued if >40 ng/L) and annually thereafter (with trial medication discontinued if ‡50 ng/L). Median calcitonin concentrations were calculated at each time point, and thyroid malignancies were collected prospectively. Data regarding follow-up after an elevated calcitonin were collected retrospectively. RESULTS At baseline, 52 (30 exenatide and 22 placebo) participants had calcitonin >40 ng/L, and during follow-up an additional 23 participants (15 exenatide and 8 placebo) had calcitonin ‡50 ng/L in the intention-to-treat population. Median calcitonin concentrations were similar between treatment groups at baseline with no increase over time. Confirmed MTC occurred in three participants (2 exenatide and 1 placebo), all of whom had significantly elevated baseline calcitonin values (413, 422, and 655 ng/L). CONCLUSIONS During a median 3.2 years’ follow-up, no change in serum calcitonin was seen with exenatide therapy. The three confirmed cases of MTC all occurred in participants with markedly elevated baseline calcitonin levels, measured prior to trial medication administration. Regular calcitonin monitoring identified no additional cases of MTC, suggesting no benefit of routine calcitonin monitoring during exenatide treatment
History of clinical transplantation
How transplantation came to be a clinical discipline can be pieced together by perusing two volumes of reminiscences collected by Paul I. Terasaki in 1991-1992 from many of the persons who were directly involved. One volume was devoted to the discovery of the major histocompatibility complex (MHC), with particular reference to the human leukocyte antigens (HLAs) that are widely used today for tissue matching.1 The other focused on milestones in the development of clinical transplantation.2 All the contributions described in both volumes can be traced back in one way or other to the demonstration in the mid-1940s by Peter Brian Medawar that the rejection of allografts is an immunological phenomenon.3,4 © 2008 Springer New York
Lung secretion sol-phase proteins: comparison of sputum with secretions obtained by direct sampling.
Modification of the Nitrogen Content and C:N Ratio of Sitka Spruce Timber by Kiln and Air Drying
Peripheral Vascular Occlusions Leading to Gangrene and Amputations in Antiphospholipid Antibody Positive Patients
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