University of Utah

About: University of Utah is a education organization based out in Salt Lake City, Utah, United States. It is known for research contribution in the topics: Population & Medicine. The organization has 52894 authors who have published 124076 publications receiving 5265834 citations. The organization is also known as: The U & The University of Utah.

Vasculotropic, paracrine actions of infused mesenchymal stem cells are important to the recovery from acute kidney injury.

Abstract: Acute kidney injury (AKI) is a major clinical problem in which a critical vascular, pathophysiological component is recognized. We demonstrated previously that mesenchymal stem cells (MSC), unlike fibroblasts, are significantly renoprotective after ischemia-reperfusion injury and concluded that this renoprotection is mediated primarily by paracrine mechanisms. In this study, we investigated whether MSC possess vasculoprotective activity that may contribute, at least in part, to an improved outcome after ischemia-reperfusion AKI. MSC-conditioned medium contains VEGF, HGF, and IGF-1 and augments aortic endothelial cell (EC) growth and survival, a response not observed with fibroblast-conditioned medium. MSC and EC share vasculotropic gene expression profiles, as both form capillary tubes in vitro on Matrigel alone or in cooperation without fusion. MSC undergo differentiation into an endothelial-like cell phenotype in culture and develop into vascular structures in vivo. Infused MSC were readily detected in the kidney early after reflow but were only rarely engrafted at 1 wk post-AKI. MSC attached in the renal microvascular circulation significantly decreased apoptosis of adjacent cells. Infusion of MSC immediately after reflow in severe ischemia-reperfusion AKI did not improve renal blood flow, renovascular resistance, or outer cortical blood flow. These data demonstrate that the unique vasculotropic, paracrine actions elicited by MSC play a significant renoprotective role after AKI, further demonstrating that cell therapy has promise as a novel intervention in AKI.

Evaluation of optimization methods for control allocation

Abstract: The performanceand computational requirements ofoptimization methodsfor control allocation areevaluated Two control allocation problems are formulated: a direct allocation method that preserves the directionality of the moment and a mixed optimization method that minimizes the error between the desired and the achieved momentsaswellasthecontroleffortTheconstrainedoptimizationproblemsaretransformedinto linearprograms so that they can be solved using well-tried linear programming techniques such as the simplex algorithm A variety of techniques that can be applied for the solution of the control allocation problem in order to accelerate computations are discussed Performance and computational requirements are evaluated using aircraft models with different numbers of actuators and with different properties In addition to the two optimization methods, three algorithms with low computational requirements are also implemented for comparison: a redistributed pseudoinverse technique, a quadratic programming algorithm, and a e xed-point method The major conclusion is that constrained optimization can be performed with computational requirements that fall within an order of magnitude of those of simpler methods The performance gains of optimization methods, measured in terms of the error between the desired and achieved moments, are found to be small on the average but sometimes signie cantAvariety ofissuesthataffecttheimplementation ofthevariousalgorithmsin ae ight-controlsystem are discussed

Absolute Rate Theory for Isolated Systems and the Mass Spectra of Polyatomic Molecules.

Abstract: been of fundamental importance in the development of present-day physical theories. As has been stated so many times, the general problem is now solved "in principle" by the quantum mechanics, but the application of the theory to only the simplest systems has been practicable.l, 2 In recent years a very large amount of data has been accumulated on the "mass spectra" resulting from the bombardment of molecules by electrons of energy 50 and 70 volts.3 There is also a significant amount of data on special aspects of the mass spectra of a few polyatomic molecules. A reasonably exact analysis of a mass spectrum would require detailed knowledge of all the electronic states both of the molecule and of all the ions formed from it by removal of electrons and by removal and rearrangement of nuclei. In this paper we present a statistical approach to the problem. Necessarily, assumptions and approximations are required. 'While this theory is in no way complete, we believe it permits the discussion and coordination of a large amount of the available data in terms of the structure of molecules and ions. Knowledge of the effect of low-voltage electron bombardment on molecules, besides being of interest in its own right, has varied applications. It has bearing on the relation of molecular structure to chemical reactivity. It is well known that the major fraction of the effect of high energy radiation on matter, including living systems, is due to the low energy secondary electrons.4 The rate theory presented here should also be applicable to other problems involving isolated systems having a large but finite number of degrees of freedom. The ionization and dissociation of diatomic molecules by electron impact has by now become quite well understood. Hagstrum5 has recently discussed in great detail the mass spectra of a number of diatomic molecules, explaining the formation of the several ions and their kinetic energies in terms of Franck-Condon transitions to the various electronic states of the diatomic ions. Another discussion is that of Stevenson6 who calculated the relative abundance ratios H+/H2+ and D+/D2+ in the mass spectra of hydrogen and deuterium, again using the picture of Franck-Condon transitions to known electronic states. While any discussion of large polyatomic molecules mass spectra must be in accord with these discussions, the direct application of the same methods is impossible.

Evidence-based path to newborn screening for Duchenne muscular dystrophy.

Abstract: Objective: Creatine kinase (CK) levels are increased on dried blood spots in newborns related to the birthing process. As a marker for newborn screening, CK in Duchenne muscular dystrophy (DMD) results in false-positive testing. In this report, we introduce a 2-tier system using the dried blood spot to first assess CK with follow-up DMD gene testing. Methods: A fluorometric assay based upon the enzymatic transphosphorylation of adenosine diphosphate to adenosine triphosphate was used to measure CK activity. Preliminary studies established a population-based range of CK in newborns using 30,547 deidentified anonymous dried blood spot samples. Mutation analysis used genomic DNA extracted from the dried blood spot followed by whole genome amplification with assessment of single-/multiexon deletions/duplications in the DMD gene using multiplex ligation-dependent probe amplification. Results: DMD gene mutations (all exonic deletions) were found in 6 of 37,649 newborn male subjects, all of whom had CK levels >2,000U/l. In 3 newborns with CK >2,000U/l in whom DMD gene abnormalities were not found, we identified limb-girdle muscular dystrophy gene mutations affecting DYSF, SGCB, and FKRP. Interpretation: A 2-tier system of analysis for newborn screening for DMD has been established. This path for newborn screening fits our health care system, minimizes false-positive testing, and uses predetermined levels of CK on dried blood spots to predict DMD gene mutations. ANN NEUROL 2012;71:304–313