150 research outputs found
Bone marrow mononuclear cells and acute myocardial infarction
PMCID: PMC3340546This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
Alternative Access for Transcatheter Aortic Valve Implantation: Current Evidence and Future Directions
Transcatheter aortic valve implantation (TAVI) is the usual technique for patients with severe aortic stenosis who are at high risk for surgical aortic valve replacement. The transfemoral (TF) route is the most commonly used access type, and significant progress in this procedure has greatly increased the proportion of patients who can undergo it. Not all patients are suitable for TF TAVI, however, so other routes, including transapical, transaortic, subclavian, trans-subclavian/transaxillary, transcarotid and transcaval, may need to be used. Evidence on these routes shows promising results but the majority of this is registry data rather than randomised controlled trials, so TF TAVI remains the safest access route and should be considered for most patients. However, in patients who are unsuitable for TF TAVI, alternative access routes are safe and feasible. The challenges concern choosing the best route, the valve to use and skill of the specialist centre. This article provides a overview of options for alternative vascular access in TAVI, the clinical rationale for using them, current evidence and areas for clinical investigation
Timelapse
We discuss the existence in an arbitrary frame of a finite time for the
transformation of an initial quantum state into another e.g. in a decay.
This leads to the introduction of a timelapse in analogy with
the lifetime of a particle. An argument based upon the Heisenberg uncertainty
principle suggests the value of . Consequences for the
exponential decay formula and the modifications that introduces
into the Breit-Wigner mass formula are described.Comment: 5 pages [2 figs], ReV-Te
Angular distribution studies on the two-photon ionization of hydrogen-like ions: Relativistic description
The angular distribution of the emitted electrons, following the two-photon
ionization of the hydrogen-like ions, is studied within the framework of second
order perturbation theory and the Dirac equation. Using a density matrix
approach, we have investigated the effects which arise from the polarization of
the incoming light as well as from the higher multipoles in the expansion of
the electron--photon interaction. For medium- and high-Z ions, in particular,
the non-dipole contributions give rise to a significant change in the angular
distribution of the emitted electrons, if compared with the electric-dipole
approximation. This includes a strong forward emission while, in dipole
approxmation, the electron emission always occurs symmetric with respect to the
plane which is perpendicular to the photon beam. Detailed computations for the
dependence of the photoelectron angular distributions on the polarization of
the incident light are carried out for the ionization of H, Xe, and
U (hydrogen-like) ions.Comment: 16 pages, 4 figures, published in J Phys
Enzymatic depolymerization of gum Tragacanth: Bifidogenic potential of low molecular weight oligosaccharides
Randomised trial of combination cytokine and adult autologous bone marrow progenitor cell administration in patients with non-ischaemic dilated cardiomyopathy - the regenerate-dcm randomized phase II
The REGENERATE-DCM trial is the first phase II randomized, placebo-controlled trial aiming to assess if granulocyte
colony-stimulating factor (G-CSF) administration with or without adjunctive intracoronary (IC) delivery of autologous
bone marrow-derived cells (BMCs) improves global left ventricular (LV) function in patients with dilated cardiomyopathy (DCM) and significant cardiac dysfunction.
Methods
and results
Sixty patients with DCM and left ventricular ejection fraction (LVEF) at referral of ≤45%, New York Heart Association
(NYHA) classification ≥2 and no secondary cause for the cardiomyopathy were randomized equally into four groups:
peripheral placebo (saline), peripheral G-CSF, peripheral G-CSF and IC serum, and peripheral G-CSF and IC BMC. All
patients, except the peripheral placebo group, received 5 days of G-CSF. In the IC groups, this was followed by bone
marrow harvest and IC infusion of cells or serum on Day 6. The primary endpoint was LVEF change from baseline to
3 months, determined by advanced cardiac imaging. At 3 months, peripheral G-CSF combined with IC BMC therapy
was associated with a 5.37% point increase in LVEF (38.30%+12.97 from 32.93%+16.46 P ¼ 0.0138), which was
maintained to 1 year. This was associated with a decrease in NYHA classification, reduced NT-pro BNP, and improved
exercise capacity and quality of life. No significant change in LVEF was seen in the remaining treatment groups.
Conclusion This is the first randomized, placebo-controlled trial with a novel combination of G-CSF and IC cell therapy that
demonstrates an improvement in cardiac function, symptoms, and biochemical parameters in patients with DCM.The trial was supported by unrestricted grants from the Heart Cells Foundation and Barts and the London Charity. Chugai Pharmaceutical donated supplies of G-CSF and pharmaceutical costs. Funding to pay the Open Access publication charges for this article was provided by the Barts Cardiovascular Biomedical Research Unit (CVBRU)
Distribution of Temperature and Strength in the Central Andean Lithosphere and Its Relationship to Seismicity and Active Deformation
We present three-dimensional (3D) models of the present-day steady-state conductive thermal field and strength distribution in the lithosphere beneath the Central Andes. Our primary objective was to investigate the influence that the structure of the Central Andean lithosphere has on its thermal and rheological state, and the relationship between the latter and the active deformation in the region. We used our previous data-driven and gravity-constrained 3D density model as starting point for the calculations. We first assigned lithology-derived thermal and rheological properties to the different divisions of the density model and defined temperature boundary conditions. We then calculated the 3D steady-state conductive thermal field and the maximum differential stresses for both brittle and ductile behaviors. We find that the thickness and composition of the crust are the main factors affecting the modeled thermal field, and consequently also the strength distribution. The orogen is characterized by a thick felsic crust with elevated temperatures and a low integrated strength, whereas the foreland and forearc are underlain by a more mafic and thinner crust with lower temperatures and a higher integrated strength. We find that most of the intraplate deformation coincides spatially with the steepest strength gradients and suggest that the high potential energy of the orogen together with the presence of rheological lateral heterogeneities produce high compressional stresses and strong strain localization along the margins of the orogen. We interpret earthquakes within the modeled ductile field to be related to the weakening effect of long-lived faults and/or the presence of seismic asperities.Fil: Ibarra, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Prezzi, Claudia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Bott, Judith. German Research Centre for Geosciences; AlemaniaFil: Scheck Wenderoth, Magdalena. German Research Centre for Geosciences; AlemaniaFil: Strecker, Manfred. Universitat Potsdam; Alemani
Hydrophilic antioxidant compounds in orange juice from different fruit cultivars: Composition and antioxidant activity evaluated by chemical and cellular based (Saccharomyces cerevisiae) assays
Antioxidant capacity was evaluated by a cellular model (Saccharomyces cerevisiae) and chemical
methods (FRAP, TEAC and total phenols by Folin-Ciocalteu assay) in the hydrophilic fraction (phenolic
compounds and ascorbic acid) of orange juices (OJs) from six varieties (Midknight, Delta Seedless, Rohde
Red, Seedless, Early and clone Sambiasi), harvested in two seasons. The contents of phenolic compounds
and ascorbic acid analyzed, respectively, by UPLC and HPLC were 370.04 76.97 mg/L and
52.05 6.69 mg/100 mL. Variety and season significantly influenced (p < 0.05) composition and antioxidant
capacity. TEAC and FRAP values correlated well with individual hydrophilic compounds (R2 > 0.991) but no
correlation with cellular assay was observed. An increase in survival rates between 23% and 38% was
obtained, excepting for two varieties that showed no activity (Rohde Red and Seedless). Narirutin, naringin-d,
ferulic acid-d2, didymin, neoeriocitrin and sinapic acid hexose and caffeic acid-d1 were the phenolic
compounds which contributed to survival rates (R2 = 0.979, p < 0.01
Functional Effects of Parasites on Food Web Properties during the Spring Diatom Bloom in Lake Pavin: A Linear Inverse Modeling Analysis
This study is the first assessment of the quantitative impact of parasitic chytrids on a planktonic food web. We used a carbon-based food web model of Lake Pavin (Massif Central, France) to investigate the effects of chytrids during the spring diatom bloom by developing models with and without chytrids. Linear inverse modelling procedures were employed to estimate undetermined flows in the lake. The Monte Carlo Markov chain linear inverse modelling procedure provided estimates of the ranges of model-derived fluxes. Model results support recent theories on the probable impact of parasites on food web function. In the lake, during spring, when ‘inedible’ algae (unexploited by planktonic herbivores) were the dominant primary producers, the epidemic growth of chytrids significantly reduced the sedimentation loss of algal carbon to the detritus pool through the production of grazer-exploitable zoospores. We also review some theories about the potential influence of parasites on ecological network properties and argue that parasitism contributes to longer carbon path lengths, higher levels of activity and specialization, and lower recycling. Considering the “structural asymmetry” hypothesis as a stabilizing pattern, chytrids should contribute to the stability of aquatic food webs
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