Chiral Analysis of the Generalized Form Factors of the Nucleon

We apply the methods of Chiral Perturbation Theory to the analysis of the first moments of the Generalized Parton Distributions in a Nucleon, usually known as generalized form factors. These quantities are currently also under investigation in Lattice QCD analyses of baryon structure, providing simulation results at large quark masses to be extrapolated to the "real world" via Chiral Effective Field Theory. We have performed a leading-one-loop calculation in the covariant framework of Baryon Chiral Perturbation Theory (BChPT), predicting both the momentum and the quark-mass dependence for all the vector and axial (generalized) form factors. In particular we discuss the results for the limit of vanishing four-momentum transfer where the GPD-moments reduce to the well known moments of Parton Distribution Functions (PDFs). We fit our results to available lattice QCD data, extrapolating down to the physical point. We conclude by presenting outstanding results from a combined fit to different GPDs-moments.Comment: 7 pages, 4 figures, Proceedings of Lattice 2007 (July 30 - 4 August 2007, Regensburg, Germany

Liposome Formulation and In Vitro Testing in Non-Physiological Conditions Addressed to Ex Vivo Kidney Perfusion

This work focuses on formulating liposomes to be used in isolated kidney dynamic machine perfusion in hypothermic conditions as drug delivery systems to improve preservation of transplantable organs. The need mainly arises from use of kidneys from marginal donors for transplantation that are more exposed to ischemic/reperfusion injury compared to those from standard donors. Two liposome preparation techniques, thin film hydration and microfluidic techniques, are explored for formulating liposomes loaded with two model proteins, myoglobin and bovine serum albumin. The protein-loaded liposomes are characterized for their size by DLS and morphology by TEM. Protein releases from the liposomes are tested in PERF-GEN perfusion fluid, 4 °C, and compared to the in vitro protein release in PBS, 37 °C. Fluorescent liposome uptake is analyzed by fluorescent microscope in vitro on epithelial tubular renal cell cultures and ex vivo on isolated pig kidney in hypothermic perfusion conditions. The results show that microfluidics are a superior technique for obtaining reproducible spherical liposomes with suitable size below 200 nm. Protein encapsulation efficiency is affected by its molecular weight and isoelectric point. Lowering incubation temperature slows down the proteins release; the perfusion fluid significantly affects the release of proteins sensitive to ionic media (such as BSA). Liposomes are taken up by epithelial tubular renal cells in two hours' incubation time