Mid-term Results of Chimney and Periscope Grafts in Supra-aortic Branches in High Risk Patients.

PURPOSE: Report mid-term outcomes of thoracic endovascular aneurysm repair (TEVAR) with chimney and periscope grafts (CPG) in supra-aortic branches (SAB). METHODS: Retrospective analysis, from October 2009 to May 2014, of patients with aneurysms requiring TEVAR with zone 0/1/2 proximal landing in association with at least one CPG in the SAB. All patients were considered at high risk for conventional surgery. Peri-operative mortality and morbidity, retrograde type A dissection, maximum aortic transverse diameter (TD) and its post-operative evolution, endoleak, survival, freedom from cardiovascular re-interventions, and CPG freedom from occlusion during the follow-up were analysed. RESULTS: Forty-one patients (28.05% EuroScore II) with thoraco-abdominal aortic aneurysm (17%), arch aneurysm (39%), descending aneurysm (34%), and aneurysm extending from the arch to the visceral aorta (10%) were included. Fifteen (37%) patients were treated non-electively. Fifty-nine SABs were treated with the CPG technique: one, two, three, and four CPG were employed in 71%, 19%, 5%, and 5% of patients, respectively. The proximal landing was in zone 0 in 49% of patients, zone 1 in 17%, and zone 2 in 34%. Technical success was 95%. Peri-operative complications and neurological events were registered in six (14.6%) patients and there were 5 deaths (12%). At a median follow-up of 21.2 (mean 22, SD 18; range 0-65) months, type I/III endoleaks were registered in three (7%) cases and re-intervention in six (15%) patients. A significant aneurysm sac shrinkage (p<.001) was reported at mean follow-up and no significant aneurysm sac increase (>5 mm). The estimated 2 year survival, freedom from re-intervention, freedom from endoleak, and freedom from branch occlusion were 75%, 77%, 86%, and 96%, respectively. CONCLUSION: The chimney and periscope grafts technique was shown to be safe in aortic aneurysm disease involving the supra aortic branches, even in an emergency setting using off the shelf devices. Mid-term follow-up results in this high risk population are good, but longer follow-up is mandatory before this technique is used in intermediate-risk patients.

Dynamical phase diagram of Gaussian wave packets in optical lattices.

We study the dynamics of self-trapping in Bose-Einstein condensates (BECs) loaded in deep optical lattices with Gaussian initial conditions, when the dynamics is well described by the discrete nonlinear Schrödinger equation (DNLSE). In the literature an approximate dynamical phase diagram based on a variational approach was introduced to distinguish different dynamical regimes: diffusion, self-trapping, and moving breathers. However, we find that the actual DNLSE dynamics shows a completely different diagram than the variational prediction. We calculate numerically a detailed dynamical phase diagram accurately describing the different dynamical regimes. It exhibits a complex structure that can readily be tested in current experiments in BECs in optical lattices and in optical waveguide arrays. Moreover, we derive an explicit theoretical estimate for the transition to self-trapping in excellent agreement with our numerical findings, which may be a valuable guide as well for future studies on a quantum dynamical phase diagram based on the Bose-Hubbard Hamiltonian.

Nuclear charge radius of 12Be.

The nuclear charge radius of (12)Be was precisely determined using the technique of collinear laser spectroscopy on the 2s(1/2)→2p(1/2,3/2) transition in the Be(+) ion. The mean square charge radius increases from (10)Be to (12)Be by δ(10,12)=0.69(5) fm(2) compared to δ(10,11)=0.49(5) fm(2) for the one-neutron halo isotope ^{11}Be. Calculations in the fermionic molecular dynamics approach show a strong sensitivity of the charge radius to the structure of ^{12}Be. The experimental charge radius is consistent with a breakdown of the N=8 shell closure.

Nuclear charge radii of (21-32)Mg.

Charge radii of all magnesium isotopes in the sd shell have been measured, revealing evolution of the nuclear shape throughout two prominent regions of assumed deformation centered on (24)Mg and (32)Mg. A striking correspondence is found between the nuclear charge radius and the neutron shell structure. The importance of cluster configurations towards N=8 and collectivity near N=20 is discussed in the framework of the fermionic molecular dynamics model. These essential results have been made possible by the first application of laser-induced nuclear orientation for isotope shift measurements.

Pair decay width of the Hoyle state and its role for stellar carbon production.

The pair decay width of the first excited 0+ state in 12C (the Hoyle state) is deduced from a novel analysis of the world data on inelastic electron scattering covering a wide momentum transfer range, thereby resolving previous discrepancies. The extracted value Γπ=(62.3±2.0) µeV is independently confirmed by new data at low momentum transfers measured at the S-DALINAC and reduces the uncertainty of the literature values by more than a factor of 3. A precise knowledge of Γπ is mandatory for quantitative studies of some key issues in the modeling of supernovae and of asymptotic giant branch stars, the most likely site of the slow-neutron nucleosynthesis process.

Chromatin maps, histone modifications and leukemia.

Recent years have seen great advances in the understanding of epigenetic gene regulation. Many of the molecular players involved have recently been identified and are rapidly being characterized in detail. Genome scale studies, using chromatin immunoprecipitation followed by expression arrays ('ChIP-Chip') or next generation sequencing ('ChIP-Seq'), have been applied to the study of transcription factor binding, DNA methylation, alternative histone use, and covalent histone modifications such as acetylation, ubiquitination and methylation. Initial studies focused on yeast, and embryonic stem cells. Genome-wide studies are now also being employed to characterize cancer and specifically leukemia genomes, with the prospect of improved diagnostic accuracy and discovery of novel therapeutic strategies. Here, we review some of the epigenetic modifications and their relevance for leukemia.

Masses and charge radii of 17-22Ne and the two-proton-halo candidate 17Ne.

High-precision mass and charge radius measurements on ;{17-22}Ne, including the proton-halo candidate 17Ne, have been performed with Penning trap mass spectrometry and collinear laser spectroscopy. The 17Ne mass uncertainty is improved by factor 50, and the charge radii of ;{17-19}Ne are determined for the first time. The fermionic molecular dynamics model explains the pronounced changes in the ground-state structure. It attributes the large charge radius of 17Ne to an extended proton configuration with an s;{2} component of about 40%. In 18Ne the smaller radius is due to a significantly smaller s;{2} component. The radii increase again for ;{19-22}Ne due to cluster admixtures.

Postconditioning with a volatile anaesthetic in alveolar epithelial cells in vitro.

Acute lung injury is a common complication in critically ill patients. The present study examined possible immunomodulating effects of the volatile anaesthetic sevoflurane on lipopolysaccharide (LPS)-stimulated alveolar epithelial cells (AEC) in vitro. Sevoflurane was applied after the onset of injury, simulating a "postconditioning" scenario. Rat AEC were stimulated with LPS for 2 h, followed by a 4-h co-exposure to a CO(2)/air mixture with sevoflurane 2.2 volume %; control cells were exposed to the CO(2)/air mixture only. Cytokine-induced neutrophil chemoattractant-1, monocyte chemoattractant protein-1, intercellular adhesion molecule-1, as well as the potential protective mediators inducible nitric oxide synthase (iNOS)2 and heat shock protein (HSP)-32, were analysed. Additionally, functional assays (chemotaxis, adherence and cytotoxicity assay) were performed. A significant reduction of inflammatory mediators in LPS-stimulated, sevoflurane-exposed AEC was found, leading to reduced chemotaxis, neutrophil adherence and neutrophil-induced AEC killing. While iNOS2 was increased in the sevoflurane group, blocking experiments with iNOS2 inhibitor did not affect sevoflurane-induced decrease of inflammatory mediators and AEC killing. Interestingly, sevoflurane treatment also resulted in an enhanced expression of HSP-32. The data presented in the current study provide strong evidence that anaesthetic postconditioning with sevoflurane mediates cytoprotection in the respiratory compartment in an in vitro model of acute lung injury.

Hypoxia attenuates effector-target cell interaction in the airway and pulmonary vascular compartment.

Leucocyte infiltration is known to play an important role in hypoxia-induced tissue damage. However, little information is available about hypoxia and interaction of effector (neutrophils) with target cells (alveolar epithelial cells, AEC; rat pulmonary artery endothelial cells, RPAEC). The goal of this study was to elucidate hypoxia-induced changes of effector-target cell interaction. AEC and RPAEC were exposed to 5% oxygen for 2-6 h. Intercellular adhesion molecule-1 (ICAM-1) expression was determined and cell adherence as well as cytotoxicity assays were performed. Nitric oxide and heat shock protein 70 (HSP70) production was assessed in target cells. Under hypoxic conditions enhanced ICAM-1 production was found in both cell types. This resulted in an increase of adherent neutrophils to AEC and RPAEC. The death rate of hypoxia-exposed target cells decreased significantly in comparison to control cells. Nitric oxide (NO) concentration was enhanced, as was production of HSP70 in AEC. Blocking NO production in target cells resulted in increased cytotoxicity in AEC and RPAEC. This study shows for the first time that target cells are more resistant to effector cells under hypoxia, suggesting hypoxia-induced cell protection. An underlying mechanism for this phenomenon might be the protective effect of increased levels of NO in target cells.

Structure of the Hoyle state in 12C.

The first excited 0(+) state in 12C (Hoyle state) has been predicted to be a dilute self-bound gas of bosonic alpha particles, similar to a Bose-Einstein condensate. To clarify this conjecture, precise electron scattering data on form factors of the ground state and the transition to the Hoyle state are compared with results of the fermionic molecular dynamics model, a microscopic alpha-cluster model, and an alpha-cluster model with reduced degrees of freedom (in the spirit of a Bose-Einstein condensed state). The data indicate clearly a dilute density with a large spatial extension of the Hoyle state. A closer inspection of the model calculations, which reproduce the experimental findings, reveals that the term Bose-Einstein condensation of three alpha particles must not be taken too literally.

Flow rate, syringe size and architecture are critical to start-up performance of syringe pumps.

BACKGROUND AND OBJECTIVE: Significant start-up delays are inherent to syringe infusion pumps, particularly at low infusion rates, as routinely used in children's anaesthesia and intensive care. Such delays are mainly the result of engagement of gears in the mechanical drive or compliance of the syringe assembly. The purpose of the present study was to determine the effect of flow rate, syringe size and syringe architecture on fluid delivery during infusion start-up. METHODS: Elapsed time from infusion start to achievement of steady-state flow was gravimetrically determined for various infusion rates (0.1, 0.5, 1 mL h-1), different syringe sizes (10-, 20-, 30-, 50-mL) and syringes of two different brands (BD and Codan). Four measurements for each condition were performed with two identical Alaris Asena GH syringe infusion pumps (total of eight experiments). Statistical analysis was done by two-way ANOVA with Bonferroni's post-test; P < 0.05 was considered significant. RESULTS: Start-up time was from 3.6 +/- 0.9 min (BD 10-mL syringe, 1.0 mL h-1) to 74.5 +/- 26.6 min (BD 50-mL syringe, 0.1 mL h-1). Overall, the start-up time markedly increased with lower flow rate (0.1 mL h-1 vs. 1 mL h-1; P < 0.0001), larger syringe size (50 mL vs. 10 mL; P < 0.01), and the BD brand in comparison with the Codan syringes (P < 0.01). CONCLUSIONS: Highest possible flow rate, smaller sized syringes and syringe plungers with reduced compressibility should be preferred in order to avoid significant start-up delays in fluid delivery.

An optimized workflow for the integration of biological information into radiotherapy planning: experiences with T1w DCE-MRI.

Planning of radiotherapy is often difficult due to restrictions on morphological images. New imaging techniques enable the integration of biological information into treatment planning and help to improve the detection of vital and aggressive tumour areas. This might improve clinical outcome. However, nowadays morphological data sets are still the gold standard in the planning of radiotherapy. In this paper, we introduce an in-house software platform enabling us to combine images from different imaging modalities yielding biological and morphological information in a workflow driven approach. This is demonstrated for the combination of morphological CT, MRI, functional DCE-MRI and PET data. Data of patients with a tumour of the prostate and with a meningioma were examined with DCE-MRI by applying pharmacokinetic two-compartment models for post-processing. The results were compared with the clinical plans for radiation therapy. Generated parameter maps give additional information about tumour spread, which can be incorporated in the definition of safety margins.

Accurate continuous drug delivery at low infusion rate with a novel microvolumetric infusion pump (MVIP): pump design, evaluation and comparison to the current standard.

Infusion devices for continuous and precise drug administration are indispensable tools in anaesthesia and critical care medicine. Problems such as start-up delays, non-continuous flow and susceptibility to hydrostatic pressure changes at low infusion rates resulting in accidental bolus release or prolonged flow interruption are inherent to current infusion technology. In order to improve precise drug delivery, an innovative technical concept has been realised in a novel microvolumetric infusion pump (MVIP) device. The MVIP principle includes repeated filling and emptying of a non-compliant microsyringe without the use of valves. The performance of the MVIP prototype has been evaluated and compared with standard syringe infusion pump assemblies. The novel MVIP concept has thereby proven to eliminate most problems during infusion start-up, steady state flow and vertical pump displacement, and has the potential of revolutionising infusion technology and setting a new dimension in patient safety.

Warming of infusion syringes caused by electronic syringe pumps.

PURPOSE: To evaluate inadvertent warming of the infusion syringe in four different types of electronic syringe pumps. METHODS: Ambient temperature and syringe surface temperature were simultaneously measured by two electronic temperature probes in four different models of commercially available syringe pumps. Experiments were performed at an infusion rate of 1 ml h(-1) using both battery-operated and main power-operated pumps. Measurements were repeated four times with two pumps from each of the four syringe pump types at a room temperature of approximately 23 degrees C. Differences among the four syringe pump brands regarding ambient to syringe temperature gradient were compared using ANOVA. A P-value of less than 0.05 was considered statistically significant. RESULTS: Syringe warming differed significantly between the four syringe brands for both the battery-operated and main power-operated mode (ANOVA, P< 0.001 for both modes). Individual differences between syringe surface and ambient temperature ranged from 0.3 to 1.9 degrees C for battery operation and from 0.5 to 11.2 degrees C during main-power operation. CONCLUSION: Infusion solutions can be significantly warmed by syringe pumps. This has potential impact on bacterial growth and the stability of drug solutions and blood products infused, as well as on the susceptibility to hydrostatic pressure changes within the infusion syringe.

Start-up delays of infusion syringe pumps.

BACKGROUND: We performed a bench experiment to investigate the extent of start-up delays in fluid delivery for four different syringe pumps after initially placing the infusion syringe in the syringe pump. METHODS: Pump performance was determined at an infusion rate of 1 ml.h-1 with and without a fluid bolus delivered by the infusion pump prior to connecting the infusion line to the simulated patient. RESULTS: The time (mean +/- SD) from starting the pump up to first fluid delivery (t1) differed considerably between pumps (from 6.75 +/- 4.4 to 57.2 +/- 28.6 min) as did the time to steady state fluid delivery (t2) (from 19.6 +/- 9.3 to 76.3 +/- 29.0 min). Applying an initial bolus of 2 ml before connecting the line to the simulated patient practically eliminated the delay in fluid delivery (t1 ranging from 0.3 +/- 0.1 to 1.1 +/- 0.8 min). This manoeuvre also reduced the time to steady flow delivery (t2 from 6.0 +/- 3.1 to 11.1 +/- 4.3 min, P<0.001) and minimized the differences between syringe pumps. CONCLUSIONS: Syringe pump design affects start-up delay times because of free play of the syringe. These delays can be eliminated by a start-up bolus of 2 ml prior to connecting the infusion line to the patient.

Receptor specificity in the self-renewal and differentiation of primary multipotential hemopoietic cells.

To determine whether cytokine-induced signals generate unique responses in multipotential hemopoietic progenitor cells, the signaling domains of 3 different growth factor receptors (Mpl, granulocyte-colony-stimulating factor [G-CSF] receptor, and Flt-3) were inserted into mouse primary bone marrow cells. To circumvent the activation of endogenous receptors, each signaling domain was incorporated into an FK506 binding protein (FKBP) fusion to allow for its specific activation using synthetic FKBP ligands. Each signaling domain supported the growth of Ba/F3 cells; however, only Mpl supported the sustained growth of transduced marrow cells, with a dramatic expansion of multipotential progenitors and megakaryocytes. These findings demonstrate that the self-renewal and differentiation of multipotential progenitor cells can be influenced through distinct, receptor-initiated signaling pathways.

Evaluation of the FASTSTART mode for reducing start-up delay in syringe pump infusion systems.

OBJECTIVE: The aim of the study was to evaluate the IVAC P7000 FASTSTART mode with regard to start-up performance in a 50-ml infusion syringe at a flow rate of 1 ml.h-1. METHODS: The time from depression of the start button to first fluid flow (T1) and to establishment of a pre-set flow rate (T2) were gravimetrically recorded with and without FASTSTART and with and without priming of the infusion system with a 1-ml fluid bolus prior to connection of the infusion line to the patient. RESULTS: FASTSTART significantly reduced start-up times in the unprimed syringe pump infusion system from (mean [SD]) 9.4 (6.0) to 2.5 (3.5) min for T1 and from 21.8 (9.8) to 9.4 (6.2) min for T2 (all p < 0.001). The greatest improvement in shortening of T1 and T2 was obtained when the system was primed prior to starting (p < 0.0001). After priming the infusion system, FASTSTART shortened T2 by some 50% from 1.4 (1.4) to 0.7 (0.6) min. CONCLUSION: Our data indicate that the FASTSTART procedure is effective and that substantial improvements can be obtained by priming the system prior to starting.

Always flush the sampling port before flushing the arterial cannula in pediatric patients.

BACKGROUND: Blood sampling from arterial lines is a frequent event in anesthesia and critical care. To avoid clot formation, both the stopcock outlet and the cannula must be flushed after sampling. We investigated in a bench experiment whether fluid flow through the cannula is affected by the sequence of flushing procedures. METHODS: Continuity of fluid delivery from a vascular cannula was gravimetrically determined using two different flushing techniques with either a syringe pump flush system or a bag flush system. The procedures comprised first flushing the stopcock towards the cannula and then towards the stopcock sampling outlet or the reverse order. Experiments were repeated in triplicate and two sets for each flushing system at hydrostatic pressures of 37 mm Hg and 74 mm Hg. RESULTS: The main finding of the study was that flushing the stopcock towards the outlet after flushing the cannula resulted in considerable retrograde aspiration volumes and zero flow times, in particular in combination with syringe pump flush systems. At a hydrostatic pressure of 74 mm Hg, the observed zero flow time at the cannula tip amounted to (mean+/-SD) 0.1+/-0.01 min with the bag flush system and 7.7+/-0.5 min with the syringe pump flush system. The related retrograde aspiration volumes were 2.2+/-0.7 microl with the bag system and 30.0+/-2.0 microl with the syringe pump system. No backflow was recorded when the stopcock was first flushed to ambient pressure and then afterwards towards the cannula. CONCLUSION: Opening a flush system to ambient pressure affects the continuity of fluid delivery, particularly when using syringe pump flush systems. After blood sampling, the stopcock outlet should be flushed first followed by cannula flushing.