Crystallographic analysis of rock grain orientation at meso- and microscale levels

This paper studies the results of electron backscatter diffraction analysis of naturally deformedpolycrystalline olivine. It also defines the dependence of lattice-preferred orientations of grains on their microstructural position and size. The authors detect the basic mechanisms, consequence and thermal dynamic modes of deformation. They also show that the development of a polycrystalline structure is determined by the following consecutive activation of sliding systems (010)[100] → {0kl}[100] → (100)[010] → {100}[001] → {110}[001], when dislocation sliding and diffusion creep change under the temperature decrease from 1000°C to 650°C

Extravascular perivenous fibrin support leads to aneurysmal degeneration and intimal hyperplasia in arterialized vein grafts in the rat

Abstract Background and aims External support of vein grafts by fibrin glue possibly prevents overdistension, vascular remodeling, and neointimal hyperplasia. Previous animal models of neointimal hyperplasia showed conflicting results. Here, long-term effects of external fibrin glue support were studied in a new rat model of jugular vein to abdominal aorta transposition. Materials and methods and methods In male Wistar rats (250-300 g) right jugular vein (1.0-1.5 cm) was transposed to the infrarenal aorta. Fibrin glue (0.25 ml) covered the vein before releasing the vascular clamps (n=6). Control vein grafts were exposed directly to blood pressure. After 16 weeks vein grafts were pressure-fixed for histology

K201 improves aspects of the contractile performance of human failing myocardium via reduction in Ca2+ leak from the sarcoplasmic reticulum

In heart failure, intracellular Ca2+ leak from cardiac ryanodine receptors (RyR2s) leads to a loss of Ca2+ from the sarcoplasmic reticulum (SR) potentially contributing to decreased function. Experimental data suggest that the 1,4-benzothiazepine K201 (JTV-519) may stabilise RyR2s and thereby reduce detrimental intracellular Ca2+ leak. Whether K201 exerts beneficial effects in human failing myocardium is unknown. Therefore, we have studied the effects of K201 on muscle preparations from failing human hearts. K201 (0.3 μM; extracellular [Ca2+]e 1.25 mM) showed no effects on contractile function and micromolar concentrations resulted in negative inotropic effects (K201 1 μM; developed tension −9.8 ± 2.5% compared to control group; P < 0.05). Interestingly, K201 (0.3 μM) increased the post-rest potentiation (PRP) of failing myocardium after 120 s, indicating an increased SR Ca2+ load. At high [Ca2+]e concentrations (5 mmol/L), K201 increased PRP already at shorter rest intervals (30 s). Strikingly, treatment with K201 (0.3 μM) prevented diastolic dysfunction (diastolic tension at 5 mmol/L [Ca2+]e normalised to 1 mmol/L [Ca2+]e: control 1.26 ± 0.06, K201 1.01 ± 0.03, P < 0.01). In addition at high [Ca2+]e, K201 (0.3 μM) treatment significantly improved systolic function [developed tension +27 ± 8% (K201 vs. control); P < 0.05]. The beneficial effects on diastolic and systolic functions occurred throughout the physiological frequency range of the human heart rate from 1 to 3 Hz. Upon elevated intracellular Ca2+ concentration, systolic and diastolic contractile functions of terminally failing human myocardium are improved by K201

Impact of Adjunct Femoral Patch Reconstruction on Graft Patency after Below the Knee Popliteal Bypass Implantation

Introduction: Acknowledging the superior long term patency of infrainguinal saphenous bypass to distal popliteal artery, debate continues regarding the choice of alternative conduits and possible surgical adjuncts to improve inflow and graft salvage. The objective of this retrospective study was to determine the effectiveness of proximal anastomotic patch as adjunct to open surgical below the knee popliteal revascularization.Material and Methods: In a series of 132 distal popliteal bypass operations 63 non-reversed vein, 18 in situ vein and 51 Omniflow bypass conduits were used. Proximal anastomotic patch was applied in overall 28 patients: 19% in the non-reversed (12 patients), 50% in the in situ group (9 patients) and 13.7% in the Omniflow group (7 patients).Results: The reintervention rate was 7.9% in the non-reversed, 33.3% in the in situ and 31.4% in the Omniflow group. The most often complication was the proximal anastomotic stenosis (5.3%), followed by bleeding (3%), infection (1.5%) and distal anastomotic stenosis (1.5%). Patch reconstruction did not decrease incidence of reoperation (21.4% vs. 21.2% in the non-patch group), nor significantly influence bleeding, infection or thrombosis, however it reduced the overall rate of proximal anastomosis stenosis (0% vs. 6.7%, p=) and significantly improved patency rate at 3 years in the in situ group compared to the non-patch group (100% vs. 55.6%, p=0.02).</p

Heart Transplantation in a Toddler with Cardiac Kawasaki Disease

Kawasaki disease is very rare in Western Europe. The disease may involve coronary arteries. A 2-year-old boy diagnosed with Kawasaki disease had had seizure-like symptoms. Further evaluation revealed recurrent myocardial ischemia and myocardial infarction. Due to extraordinary extension of the coronary disease, myocardial revascularization was not feasible and the toddler underwent successful heart transplantation after 97 days on waiting list