Beyond the physiological mild permeability-increasing (volume-regulating) effects on quiescent endothelial cells, ANP has been shown to exert barrier-protecting actions on an inflammation-activated endothelium.
The PVA/FGO composite sheet also burned out quickly, indicating that the evenly dispersed FGO does not exert its barrier effect in the condensed phase.
Early bacterial colonists of eukaryotic hosts have been shown to exert a "barrier effect" against invading microbes [ 61- 63] which may help explain why soil was not as important a source of endophytes as originally assumed.
Also, Radetzky et al. speculated about a pseudomembrane formed by the endplates of Müller cells exerting a barrier function [ 30].
Several in vitro studies suggested that probiotic adhesion may interfere with the adherence of pathogens, exerting a barrier against pathogen colonization through competitive exclusion mechanisms [ 39, 40].
With regard to the films containing no protein, corn starch probiotic films exerted poor barrier properties compared to rice starch which is supported by SEM images showing a more porous network in the corn starch films (Fig. 4).
At birth, the digestive tract is sterile and progressively colonized by flora of the mother and of the environment, which exerts a barrier effect against exogenous pathogenic bacteria, and stimulates the immune system (Rhee et al., 2004).
Indeed, thermodynamics plays an important role for microstructural engineering, unless kinetics exerts major barriers for phase transformation.
Besides blunting the Toll-like receptor-4-induced inflammatory cascade and lung dysfunction in a model of lipopolysaccharide-induced lung injury, oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphorylcholine (OxPAPC) exerts direct barrier-protective effects on pulmonary endothelial cells in vitro via activation of the small GTPases Rac and Cdc42.
Furthermore, thrombin can locally generate APC that may potentially exert its own barrier enhancing effects [ 30].
This requires a complex balance between the proliferating compartment, the differentiation compartment and the cornified envelope, which exert its protective barrier function in the epidermis.
