The human epidermoid carcinoma cell line A431 has an usually high number of specific saturable receptor sites for the mitogenic polypeptide hormone epidermal growth factor (EGF). When A431 cells were treated with unlabeled EGF in the culture medium, approximately 50% of the EGF specific binding activity was lost within a few hours (receptor down regulation). A comparison of the surface proteins...

Studies with lactoperoxidase showed that a highly reactive intermediate is produced (on the enzyme) from I- and H2O2 which then diffuses from the enzyme and very rapidly and indiscriminately iodinates any Tyr or peptides containing Tyr which are in the same solution. The evidence supporting these conclusions follows. 1) The rate followed the Michaelis-Menten pattern with I- and H2O2 while the c...

Ribosomal proteins L7 and L12 are involved in the initiation, elongation and termination of polypeptide synthesis [l-6]. These acidic proteins do not function independently, but act in concert with the ribosome to perform the above steps. These observations suggest that L7 and L12 are necessary to maintain the conformational integrity of the ribosome, and that loss of ribosomal activity followi...

The sustainable byproduct catalyzed domino strategy has been performed for the facile synthesis of α-formyloxy and acetoxy ketones via iodination/nucleophilic substitution/hydrolyzation/oxidation sequences from simple and readily available aromatic ketones/unsaturated methyl ketones.

The activity of four recombinant human cytokines on porcine neutrophils was evaluated. Porcine neutrophils were treated with varying doses of recombinant human tumour necrosis factor-alpha (rHu-TNF), interferon-gamma (rHu-IFN), interleukin-8 (rHu-lL-8), or granulocyte-macrophage colony-stimulating factor (rHu-GM-CSF). The function of treated neutrophils was compared with that of non-treated con...

CD36 is an 88-kD glycoprotein involved in the cytoadherence of Plasmodium falciparum-parasitized erythrocytes (PE) to endothelial cells. The molecular mechanisms involved in CD36-dependent cytoadherence were examined by expressing three CD36 homologues (human, murine, and rat) in COS-7 cells and observing their PE-binding characteristics over a pH range of 6.0 to 7.4 and following iodination of...