62 research outputs found
Extended DFT+U+V method with on-site and inter-site electronic interactions
In this article we introduce a generalization of the popular DFT+U method
based on the extended Hubbard model that includes on-site and inter-site
electronic interactions. The novel corrective Hamiltonian is designed to study
systems for which electrons are not completely localized on atomic states
(according to the general scheme of Mott localization) and hybridization
between orbitals from different sites plays an important role. The application
of the extended functional to archetypal Mott - charge-transfer (NiO) and
covalently bonded insulators (Si and GaAs) demonstrates its accuracy and
versatility and the possibility to obtain a unifying and equally accurate
description for a broad range of very diverse systems
Antibody responses in furunculosis patients vaccinated with autologous formalin-killed Staphylococcus aureus
Autologous vaccines (short: autovaccines) have been used since the beginning of the 20th century to treat chronic staphylococcal infections, but their mechanisms of action are still obscure. This prospective pilot study involved four patients with furunculosis who were vaccinated with autologous formalin-killed Staphylococcus aureus cells. Vaccines were individually prepared from the infecting S. aureus strain and repeatedly injected subcutaneously in increasing doses over several months. We characterized the virulence gene repertoire and spa genotype of the infecting and colonising S. aureus strains. Serum antibody responses to secreted and surface-bound bacterial antigens were determined by two-dimensional immunoblotting and flow-cytometry based assays (Luminex®). All patients reported clinical improvement. Molecular characterization showed that all strains isolated from one patient over time belonged to the same S. aureus clone. Already before treatment, there was robust antibody binding to a broad range of staphylococcal antigens. Autovaccination moderately boosted the IgG response to extracellular antigens in two patients, while the antibody response of the other two patients was not affected. Similarly, vaccination moderately enhanced the antibody response against some staphylococcal surface proteins, e.g. ClfA, ClfB, SdrD and SdrE. In summary, autovaccination only slightly boosted the pre-existing serum antibody response, predominantly to bacterial surface antigens
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