Genetic variation and potential for genetic improvement of cuticle deposition on chicken eggs.

Background: The cuticle is an invisible glycosylated protein layer that covers the outside of the eggshell and forms a barrier to the transmission of microorganisms. Cuticle-specific staining and in situ absorbance measurements have been used to quantify cuticle deposition in several pure breeds of chicken. For brown eggs, a pre-stain and a post-stain absorbance measurement is required to correct for intrinsic absorption by the natural pigment.

Cuticle deposition improves the biosecurity of eggs through the laying cycle and can be measured on hatching eggs without compromising embryonic development.

The cuticle is part of the egg's natural defense and it can be improved by genetic selection. Prior to adoption of this measurement in breeding programs, questions that need to be addressed are whether improved cuticle deposition will result in a reduced risk of eggs becoming contaminated and whether selection for this trait will have any unintended consequences on the incubation process. Bacterial penetration experiments were carried out using eggs from a pedigree line of broiler breeders (BB) and Rhode Island Red (RIR) layers.

Understanding avian egg cuticle formation in the oviduct: a study of its origin and deposition.

The cuticle is a unique invisible oviduct secretion that protects avian eggs from bacterial penetration through gas exchange pores. Despite its importance, experimental evidence is lacking for where, when, and what is responsible for its deposition. By using knowledge about the ovulatory cycle and oviposition, we have manipulated cuticle deposition to obtain evidence on these key points.

Influence of the physiochemical properties of superparamagnetic iron oxide nanoparticles on amyloid β protein fibrillation in solution.

Superparamagnetic iron oxide nanoparticles (SPIONs) are recognized as promising nanodiagnostic materials due to their biocompatibility, unique magnetic properties, and their application as multimodal contrast agents. As coated SPIONs have potential use in the diagnosis and treatment of various brain diseases such as Alzheimer's, a comprehensive understanding of their interactions with Aβ and other amyloidogenic proteins is essential prior to their clinical application. Here we demonstrate the effect of thickness and surface charge of the coating layer of SPIONs on the kinetics of fibrillation of Aβ in aqueous solution.

Dual effect of amino modified polystyrene nanoparticles on amyloid β protein fibrillation.

The fibrillation kinetics of the amyloid β peptide is analyzed in presence of cationic polystyrene nanoparticles of different size. The results highlight the importance of the ratio between the peptide and particle concentration. Depending on the specific ratio, the kinetic effects vary from acceleration of the fibrillation process by reducing the lag phase at low particle surface area in solution to inhibition of the fibrillation process at high particle surface area.

Inhibition of amyloid beta protein fibrillation by polymeric nanoparticles.

Copolymeric NiPAM:BAM nanoparticles of varying hydrophobicity were found to retard fibrillation of the Alzheimer's disease-associated amyloid beta protein (Abeta). We found that these nanoparticles affect mainly the nucleation step of Abeta fibrillation. The elongation step is largely unaffected by the particles, and once the Abeta is nucleated, the fibrillation process occurs with the same rate as in the absence of nanoparticles.