Maternal lipoproteins provide nutrients to the fetus via the placenta, yolk sac, and uterine membrane plus decidua. To determine the transport processes that are responsible for the removal of lipoproteins from the maternal circulation, we measured the clearance rates of maternal LDL and HDL in vivo, as well as the tissue distribution of expression of the LDL receptor, glycoprotein 330 (gp330) ...

A method is described for the chromatographic separation of mixtures of egg-yolk proteins of low solubility, by using a hydrophobic column (phenyl-Sepharose) and eluting with increasing concentrations of aqueous urea at low pH. The resolving power of the method was established by tests on proteins and protein fragments of known sequence. The theoretical basis for the method remains, however, un...

Current commercial broiler products are derived from the crosses of various strains at the primary breeder level. This study investigated chick development, yolk utilization, and early growth rate of males from 8 broiler breeder strains. These strains were a combination of both specialized and commercial-line products. At hatch, 110 male chicks per strain were weighed and wing-banded, and chick...

Egg yolk undergoes an irreversible gelation process at temperatures below −6 °C, which greatly impairs its application and increases apparent viscosity. This work was aimed to investigate the effect of salt pH in preventing frozen-thawed egg yolk. Before freezing, 5% added into pasteurized liquid yolk, then adjusted different levels (5.7, 6.0 6.3) with citric acid. After that, stored −18 °C for...

Progenitor cells capable of giving rise to functional macrophages in in vitro culture were first detectable in the fetal yolk sac of the mouse between day 7 and 8 of gestation. Macrophage progenitors were not detectable outside the yolk sac until day 11. Although the early yolk sac contained macrophage precursors, no cells with the morphologic or functional characteristics of mouse promonocytes...

Transcription of the three yolk protein genes of Drosophila melanogaster is under strict developmental regulation. Understanding the mechanism of this regulation requires examination of the DNA sequences and protein factors necessary for normal transcriptional control. We have identified a sequence-specific DNA-binding protein, yolk protein factor 1 (YPF1), that has high affinity for a 31-bp se...