Endoluminal stent-graft placement for repair of abdominal aortic aneurysms in the community setting.

PURPOSE: To demonstrate that results similar to high-volume academic centers can be achieved in the community setting when treating abdominal aortic aneurysm (AAA) using endovascular techniques, given appropriate volume and skill sets. METHODS: A retrospective review was conducted of 342 consecutive patients who underwent endovascular aneurysm repair (EVAR) by surgeons in a community hospital group from October 1999 through September 2005. In this population, 245 (71.6%) patients were treated with EVAR and 97 (28.4%) with open surgical repair. Of the 245 EVAR patients (203 men; mean age 73.4+/-9.2 years), 218 AneuRx, 19 Ancure, 6 Excluder, and 2 Zenith stent-grafts were implanted by 2 vascular surgeons to exclude AAAs with a mean diameter of 54+/-11 mm. Patients were followed postoperatively with office visits and computed tomography at 1, 6, and 12 months and annually thereafter. RESULTS: Technical success was achieved in 99.6% (244/245) with 1 intraoperative conversion. Mean operative time was 131+/-57 minutes, with a mean contrast load of 161.6+/-65.5 mL. Thirty-five (14.3%) patients required intraoperative blood transfusion. Length of stay was 2.3+/-4.5 days. Thirty-day mortality was 0.8% (2/245). Secondary procedures were required in 15 (6.1%) patients. Kaplan-Meier estimates of freedom from secondary interventions were 98%, 98%, 95%, and 90% at 12, 24, 36, and 48 months, respectively. At the same time points, freedom from surgical conversion was 99%, 99%, 97%, and 96%, and freedom from aneurysm-related death was 97%, 96%, 96%, and 96%. CONCLUSION: Endovascular AAA repair provides a less invasive method of managing aortic disease with resultant low perioperative mortality. Results in our community hospital demonstrate that this technology can be applied outside an academic environment in nearly three quarters of the population with excellent short and long-term results.

Calcium dynamics and resting transcriptional activity regulates prolactin gene expression.

Research on the regulation of hormone gene expression by calcium signaling is hampered by the difficulty of monitoring both parameters within the same individual, living cells. Here we achieved concurrent, dynamic measurements of both intracellular Ca(2+) concentration ([Ca(2+)](i)) and prolactin (PRL) gene promoter activity in single, living pituitary cells. Cells were transfected with the luciferase reporter gene under control of the PRL promoter and subjected to bioluminescence and fluorescence imaging before and after presentation of TSH-releasing hormone (TRH), a prototypic regulator of PRL secretion and gene expression that induces a transient Ca(2+) release, followed by sustained Ca(2+) influx. We found that cells displaying specific photonic emissions (i.e. mammotropes) showed heterogeneous calcium and transcriptional responses to TRH. Transcriptionally responsive cells always exhibited a TRH-induced [Ca(2+)](i) increase. In addition, transcriptional responses were related to the rate of Ca(2+) entry but not Ca(2+) release. Finally, cells lacking transcriptional responses (but showing [Ca(2+)](i) rises) exhibited larger levels of resting PRL promoter activity than transcriptionally responsive cells. Thus, our results suggest that the sustained entry of Ca(2+) induced by TRH (but not the Ca(2+) release) regulates transcriptional responsiveness. Superimposed on this regulation, the previous, resting PRL promoter activity also controls transcriptional responses.

PRL gene expression in individual living mammotropes displays distinct functional pulses that oscillate in a noncircadian temporal pattern.

PRL gene expression in the anterior pituitary has been the focus of intensive investigation for many years, but very little information is available on the actual dynamics by which this process occurs in individual mammotrope cells. Here, we used single cell bioluminescent imaging microscopy and a recently refined reporter gene strategy to measure PRL promoter-driven gene expression (PRL-GE) in individual living primary mammotropes. Using this approach we report a new phenomenon involving repetitive on/off gene expression bursts that occurred in a distinctly noncircadian oscillatory pattern. Furthermore, we demonstrate a functional basis for these gene expression oscillations, inasmuch as PRL-GE pulses were sensitive to calcium-dependent modulation, which we show arose exclusively as changes in the shape of individual pulse episodes. Our results provide the first clear evidence that PRL-GE, in its homologous cell environment, displays oscillatory bursts of activity. Moreover, they strongly support the idea that these discrete on/off bursts of activity serve as an important determinant of the timing and level of PRL-GE under both basal and stimulated conditions.