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225 Ac is a valuable medical radionuclide for targeted α therapy, but 227 Ac is an undesirable byproduct of an accelerator-based synthesis method under investigation. Sufficient detector sensitivity is critical for quantifying the trace impurity of 227 Ac, with the 227 Ac/ 225 Ac activity ratio predicted to be approximately 0.15% by end-of-bombardment (EOB). Superconducting transition edge sensor (TES) microcalorimeters offer high resolution energy spectroscopy using the normal-to-superconducting phase transition to measure small changes in temperature. By embedding 225 Ac production samples in a gold foil thermally coupled to a TES microcalorimeter we can measure the decay energies of the radionuclides embedded with high resolution and 100% detection efficiency. This technique, known as decay energy spectroscopy (DES), collapses several peaks from α decays into single Q-value peaks. In practice there are more complex factors in the interpretation of data using DES, which we will discuss herein. Using this technique we measured the EOB 227 Ac impurity to be (0.142 ± 0.005)% for a single production sample. This demonstration has shown that DES is a useful tool for quantitative measurements of complicated spectra., (Published by Elsevier Ltd.)

Depression is among the most common reasons for seeking psychiatric treatment, and insomnia symptoms are common in the clinical picture of depression. The present study examines the clinical presentation and psychosocial functioning among depressed outpatients with severe symptoms of insomnia in comparison to depressed outpatients without severe insomnia symptoms. The present sample included 2900 treatment-seeking individuals, with 1057 patients having a principal diagnosis of major depressive disorder (MDD). All patients were evaluated using the Structured Clinical Interview for DSM-IV Disorders (SCID), Schedule for Affective Disorders (SADS), and self-report measures of mood and psychosocial functioning. SADS Insomnia ratings were used to determine the presence of severe insomnia symptoms. Clinical, demographic, and psychosocial variables were obtained from the SCID and self-report measures. Among the patients with MDD, 24.7% endorsed severe insomnia symptoms. These individuals were older at time of presentation, were less likely to be married, had a lower education level, had a longer duration of the current depressive episode, were rated as more severe on the CGI, had poorer current functioning via GAF, and had higher HAM-D 21 scores. After controlling for severity, MDD patients with severe insomnia symptoms had poorer social functioning over the past 5 years, though this did not reach the significance level of p < .01, and significantly lower scores on 3 of the 8 SF-36 subscales (p < 0.01). These findings indicate that severe insomnia symptoms are associated with poorer psychosocial functioning and a more severe clinical presentation in patients with MDD. This argues for addressing severe insomnia symptoms among depressed patients, either via behavioral treatment or pharmacologic treatment options., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

A novel model of arterial thrombosis was developed. A mechanical endothelium-denuding injury was created (using a scalpel blade) on harvested, freezer-stored rat carotid arteries. Vessel length of 5 mm. were grafted into the femoral arteries of recipient Sprague-Dawley rats using microvascular anastomotic technique. Patency rates in untreated animals were compared with those in animals receiving systemic aspirin or heparin. The control group patency after 2 hours of flow was 15%, while grafts in aspirin- and heparin-treated animals achieved 35% and 95% patency rates, respectively. Uninjured non-frozen carotid grafts in untreated animals yielded a 95% patency rate, while frozen grafts achieved an 80% patency. Therapeutic levels of aspirin, heparin, and urokinase were confirmed through tail bleeding and whole blood clotting tests, as well as platelet aggregation studies and scanning electron microscopy of the graft lumenal surfaces. A long-term series using syngeneic grafts placed in recipients (Lewis-to-Lewis) and employing systemic heparinization demonstrated maintenance of patency for 4 weeks. Scanning electron microscopy revealed good re-endothelialization, well advanced by one week. Histology confirmed the regrowth of endothelial cells, but showed sparse cellular repopulation of medial and adventitial layers. The mechanical injury model was compared to enzymatic de-endothelialization (using trypsin or collagenase), for which patency rates were similar (10% and 0%, respectively). Trypsin de-endothelialized vessels were tested in vitro for the amount of active trypsin remaining bound to the lumenal surface; no detectable activity was found when trypsin inhibitor was applied following trypsin treatment. The versatility of allowing both in vitro evaluation and in vivo patency assessment demonstrates the uniqueness and value of this new model, offering an avenue toward more direct investigations of surface-mediated thrombotic processes.