Expression and refolding of the protective antigen of Bacillus anthracis: A model for high-throughput screening of antigenic recombinant protein refolding

Bacillus anthracis protective antigen (PA) is a well known and relevant immunogenicprotein that is the basis for both anthrax vaccines and diagnostic methods. Properly foldedantigenic PA is necessary for these applications. In this study a high level of PA was obtained inrecombinant Escherichia coli. The protein was initially accumulated in inclusion bodies, whichfacilitated its efficient purification by simple washing steps; however, it could not be recognizedby specific antibodies. Refolding conditions were subsequently analyzed in a high-throughputmanner that enabled nearly a hundred different conditions to be tested simultaneously. Therecovery of the ability of PA to be recognized by antibodies was screened by dot blot usinga coefficient that provided a measure of properly refolded protein levels with a high degreeof discrimination. The best refolding conditions resulted in a tenfold increase in the intensityof the dot blot compared to the control. The only refolding additive that consistently yieldedgood results was L-arginine. The statistical analysis identified both cooperative and negativeinteractions between the different refolding additives. The high-throughput approach describedin this study that enabled overproduction, purification and refolding of PA in a simple andstraightforward manner, can be potentially useful for the rapid screening of adequate refoldingconditions for other overexpressed antigenic proteins.Fil: Pavan, María Elisa. Biochemiq; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; ArgentinaFil: Pavan, Esteban E.. Politecnico di Milano; ItaliaFil: Cairo, Fabian Martin. Biochemiq; ArgentinaFil: Pettinari, María Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentin

Three dimensional Lifshitz black hole and the Korteweg-de Vries equation

We consider a solution of three dimensional New Massive Gravity with a negative cosmological constant and use the AdS/CTF correspondence to inquire about the equivalent two dimensional model at the boundary. We conclude that there should be a close relation with the Korteweg-de Vries equation.Comment: 4 page

A Tight Connection Between Direct and Indirect Detection of Dark Matter through Higgs Portal Couplings to a Hidden Sector

We present a hidden Abelian extension of the Standard Model including a complex scalar as a dark matter candidate and a light scalar acting as a long range force carrier between dark matter particles. The Sommerfeld enhanced annihilation cross-section of the dark matter explains the observed cosmic ray excesses. The light scalar field also gives rise to potentially large cross-sections of dark matter on nucleon, therefore providing an interesting way to probe this model simultaneously at direct and indirect dark matter search experiments. We constrain the parameter-space of the model by taking into account CDMS-II exclusion limit as well as PAMELA and FermiLAT data.Comment: 15 pages, 7 figures. Added discussions on tuning and inverse Compton scattering constraints. References added and updated. Matches the published versio

Modern public internal control systems and accountability in health care organizations

The introduction of NPM principles changed the meaning and the contents of public sector accountability as it is no longer intended as a mere compliance with rules and procedures but as the need to give an account to the citizenry, in terms of how results are achieved and resources are used in their pursuit. Accountability for results requires the modernisation of traditional control systems. These check whether regulations are followed without ensuring that the achievement of objectives is controlled. Confirming the growing need in modernizing internal control systems and increasing managerial accountability and transparency in spending public money, the European Commission has developed a reference model for the public sector: Public Internal Financial Control – PIfC. The paper tries to contribute the relevant debate on the usefulness of internal control systems by exploring the implicit positive relationship between them and managerial accountability envisaged in the PIfC model. To this end the research focuses on a case study set in the context of Italian health care sector and in the main health care organization located in the Region of Sardinia

Novel Aurora Kinase Inhibitor-Based Combination Therapies for PTCL

Peripheral T-cell lymphomas (PTCLs) are a rare, heterogeneous group of T-cell non-Hodgkin’s lymphomas (T-NHL) that display distinct clinical and biological features. Despite a detailed understanding of PTCL transformation, there is no current accepted standard of care for newly diagnosed or relapsed/refractory (r/r) patients. PTCL are highly proliferative neoplasms with an immunosuppressive microenvironment that elaborates drug resistance to current therapies with poor outcomes. Aurora kinases (AKs) are a family of mitotic oncogenic serine/threonine kinases (A, B/C) that are aberrantly expressed in PTCL, providing a growth advantage. Alisertib, an AK-A inhibitor, blocks the mitotic phase of the cell cycle resulting in apoptosis. Preclinical and clinical trials in PTCL demonstrated an ~30% response rate in r/r PTCL similar to other investigational agents. In order to improve response rates, alisertib-based combination therapies were tested with HDAC inhibitors, romidepsin and vorinostat, in phase Ib trials. To improve response rates to alisertib, we evaluated alisertib-induced polyploidy as a drug resistance mechanism by targeting microtubules with vincristine. In addition, we also targeted immunosuppression-induced proliferation with an anti-PD-L1 antibody and PI3K inhibition in PTCL. Targeting aberrant proliferation and immunosuppression is a novel strategy that warrants evaluation in clinical trials for PTCL, an unmet clinical need