It was chance that made Cajal, during his doctorate studies, have his first contact with histology and force him to study the then current theories about pathogenesis of inflammation. Thus, he gained knowledge of the vascular hypothesis, by Julius Cohnheim, a German pathologist who, opposing the opinion of his teacher and father of cellular pathology, Rudolf Virchow, made leukocytes the protagonists of inflammation, given their ability to develop ameboid movements directed by chemical STAT inhibitor signals. Cohnheim’s chemotactic theory deeply influenced Cajal’s conception of biology. So, the basic postulates of chemotaxis can be identified at different moments in Cajal’s research, from the description of the “growth
cone” in embryonic neuroblasts, the origin of the neurotrophic theory, to the proposal of the pathophysiological mechanisms of neuronal plasticity. From Cajal’s point of view, the neurons move during their development and also adapt to different external circumstances. Chemical endogenous substances can stimulate this movement in a similar way to leukocytes during the process of Wnt activation inflammation. (C) 2012 IBRO. Published by Elsevier Ltd. All rights reserved.”
“The invasive forms of apicomplexan parasites share a conserved form of gliding motility that powers parasite migration across biological
barriers, host cell invasion and egress from infected cells. Previous studies have established that the duration and direction of gliding motility are determined by actin polymerization; however, regulators of actin dynamics in apicomplexans remain poorly characterized. In the absence of a complete ARP2/3 complex, the formin selleck screening library homology 2 domain containing proteins and the accessory protein
profilin are presumed to orchestrate actin polymerization during host cell invasion. Here, we have undertaken the biochemical and functional characterization of two Toxoplasma gondii formins and established that they act in concert as actin nucleators during invasion. The importance of TgFRM1 for parasite motility has been assessed by conditional gene disruption. The contribution of each formin individually and jointly was revealed by an approach based upon the expression of dominant mutants with modified FH2 domains impaired in actin binding but still able to dimerize with their respective endogenous formin. These mutated FH2 domains were fused to the ligand-controlled destabilization domain (DD-FKBP) to achieve conditional expression. This strategy proved unique in identifying the non-redundant and critical roles of both formins in invasion. These findings provide new insights into how controlled actin polymerization drives the directional movement required for productive penetration of parasites into host cells.”
“Background: Increased visceral adipose tissue (VAT) is “pathogenic” through adverse endocrine and immune contributions to metabolic diseases such as diabetes mellitus, hypertension, and dyslipidemia.