Brucella melitensis invades murine erythrocytes during infection.

Brucella spp. are facultative intracellular Gram-negative coccobacilli responsible for brucellosis, a worldwide zoonosis. We observed that Brucella melitensis is able to persist for several weeks in the blood of intraperitoneally infected mice and that transferred blood at any time point tested is able to induce infection in naive recipient mice.

Adenylate cyclases of Trypanosoma brucei inhibit the innate immune response of the host.

The parasite Trypanosoma brucei possesses a large family of transmembrane receptor-like adenylate cyclases. Activation of these enzymes requires the dimerization of the catalytic domain and typically occurs under stress. Using a dominant-negative strategy, we found that reducing adenylate cyclase activity by about 50% allowed trypanosome growth but reduced the parasite's ability to control the early innate immune defense of the host.

The evolutionarily conserved protein Las1 is required for pre-rRNA processing at both ends of ITS2.

Ribosome synthesis entails the formation of mature rRNAs from long precursor molecules, following a complex pre-rRNA processing pathway. Why the generation of mature rRNA ends is so complicated is unclear. Nor is it understood how pre-rRNA processing is coordinated at distant sites on pre-rRNA molecules.

Critical role of regulatory T cells in Th17-mediated minor antigen-disparate rejection.

Th17-mediated immune responses have been recently identified as novel pathogenic mechanisms in a variety of conditions; however, their importance in allograft rejection processes is still debated. In this paper, we searched for MHC or minor Ag disparate models of skin graft rejection in which Th17 immune responses might be involved. We found that T cell-derived IL-17 is critical for spontaneous rejection of minor but not major Ag-mismatched skin grafts.

IL-17 production elicited by allo-major histocompatibility complex class II recognition depends on CD25posCD4pos T cells.

Background: Interleukin (IL)-17 is involved in autoimmune inflammatory disorders and naturally occurring CD25pos regulatory T cells were shown to promote IL-17 synthesis. Because IL-17 is overproduced in certain types of allograft rejection, it is important to characterize the cells responsible for IL-17 synthesis and to define how IL-17 is regulated during alloimmune responses.

Methods: Splenic CD4pos T cells were isolated from C57BL/6 mice and fractionated according to CD25 expression.

Synthesis of fiber Bragg grating parameters from experimental reflectivity: a simplex approach and its application to the determination of temperature-dependent properties.

A simple, accurate, and fast method to synthesize the physical parameters of a fiber Bragg grating numerically from its reflectivity is proposed and demonstrated. Our program uses the transfer matrix method and is based on a Nelder-Mead simplex optimization algorithm. It can be applied to both uniform and nonuniform (apodized and chirped) fiber Bragg gratings.