Thoracic Endovascular Aortic Repair in the Setting of Compromised Distal Landing Zones

Background: The short-term and intermediate-term outcomes of two distinct approaches to thoracic endovascular aortic repair (TEVAR) for descending aortic aneurysms in patients with compromised distal landing zones are reported. Methods: Fifty-one patients (38 female, average age 72 ± 9 years) underwent 55 TEVARs (2008 to 2018) for aneurysmal disease. Inclusion criteria consisted of TEVAR in a compromised distal landing zone, defined as follows: diameter 3.5 cm or greater; cross-sectional thrombus 50% or greater; or 25% or greater circumferential mural calcification in the 2 cm supraceliac aorta; or tortuosity index of 1.1 or more over the 10 cm supraceliac aorta. Treatment cohorts were (1) TEVAR alone (n = 29), and (2) TEVAR with adjunct consisting of visceral snorkel graft with distal stent extension (n = 20) or EndoAnchors (Medtronic, Minneapolis, MN [n = 6]). Results: Perioperative complication rate was 20%. Thirty-day mortality was 5% including one access-site related intraoperative death and one postoperative death from embolic mesenteric ischemia. Median clinical follow-up was 2.2 years. Intermediate-term outcomes include type 1B endoleaks, 35%; 0.5 cm or more per year maximal aortic diameter growth, 9%; reintervention, 15%; and all-cause mortality, 25%. The distal landing zone diameter increased by 0.3 cm per year in the TEVAR alone cohort; however, it decreased by 0.1 cm per year in the adjunct cohort ( P = .04). Conclusions: Thoracic endovascular aortic repair is a viable alternative for the treatment of thoracoabdominal aortic aneurysms in patients with compromised distal landing zones, although these patients may benefit significantly from the development of branched thoracoabdominal devices. In the interim, the use of TEVAR adjuncts may limit progressive degeneration of the distal landing zone in this patient population

Optical-model potential for electron and positron elastic scattering by atoms

An optical-model potential for systematic calculations of elastic scattering of electrons and positrons by atoms and positive ions is proposed. The electrostatic interaction is determined from the Dirac-Hartree-Fock self-consistent atomic electron density. In the case of electron projectiles, the exchange interaction is described by means of the local-approximation of Furness and McCarthy. The correlation-polarization potential is obtained by combining the correlation potential derived from the local density approximation with a long-range polarization interaction, which is represented by means of a Buckingham potential with an empirical energy-dependent cutoff parameter. The absorption potential is obtained from the local-density approximation, using the Born-Ochkur approximation and the Lindhard dielectric function to describe the binary collisions with a free-electron gas. The strength of the absorption potential is adjusted by means of an empirical parameter, which has been determined by fitting available absolute elastic differential cross-section data for noble gases and mercury. The Dirac partial-wave analysis with this optical-model potential provides a realistic description of elastic scattering of electrons and positrons with energies in the range from ~100 eV up to ~5 keV. At higher energies, correlation-polarization and absorption corrections are small and the usual static-exchange approximation is sufficiently accurate for most practical purposes

Seed Size, Fecundity and Postfire Regeneration Strategy Are Interdependent in Hakea

Seed size is a key functional trait that affects plant fitness at the seedling stage and may vary greatly with species fruit size, growth form and fecundity. Using structural equation modelling (SEM) and correlated trait evolution analysis, we investigated the interaction network between seed size and fecundity, postfire regeneration strategy, fruit size, plant height and serotiny (on-plant seed storage) among 82 species of the woody shrub genus, Hakea, with a wide spectrum of seed sizes (2–500 mg). Seed size is negatively correlated with fecundity, while fire-killed species (nonsprouters) produce more seeds than resprouters though they are of similar size. Seed size is unrelated to plant height and level of serotiny while it scales allometrically with fruit size. A strong phylogenetic signal in seed size revealed phylogenetic constraints on seed size variation in Hakea. Our analyses suggest a causal relationship between seed size, fecundity and postfire regeneration strategy in Hakea. These results demonstrate that fruit size, fecundity and evolutionary history have had most control over seed size variation among Hakea species

Design of Potent and Orally Active GPR119 Agonists for the Treatment of Type II Diabetes

We report herein the design and synthesis of a series of potent and selective GPR119 agonists. Our objective was to develop a GPR119 agonist with properties that were suitable for fixed-dose combination with a DPP4 inhibitor. Starting from a phenoxy analogue (<b>1</b>), medicinal chemistry efforts directed toward reducing half-life and increasing solubility led to the synthesis of a series of benzyloxy analogues. Compound <b>28</b> was chosen for further profiling because of its favorable physicochemical properties and excellent GPR119 potency across species. This compound exhibited a clean off-target profile in counterscreens and good <i>in vivo</i> efficacy in mouse oGTT