Recent studies have shown that the Sudden Infant Death Syndrome (SIDS) is related to abnormal control of respiration (Ischemic degeneration of the brainstem may play an important role in altered respiratory control leading to death). In our studies we have examined brainstem ganglioside compositions in samples derived from SIDS victims and appropriate controls. Gangliosides are acidic glycosphingolipids that contain sialic acid. The high concentration of gangliosides in the central nervous system (CNS) implies that these lipids play an important role in CNS function. Some studies have indicated that gangliosides may function as receptor site determinants or modifiers, and in neural transmission. In our studies we used the Tettamanti, et al methodology to extract gangliosides, and High Performance Thin Layer Chromatography (HPTLC) and laser densitometry techniques for ganglioside analysis. The results of these analyses are being employed to establish lipid profile patterns to determine if there are significant variations in these lipid patterns between SIDS and control groups.

Conditioned media prepared from umbilical cord (UC) segments or endothelial cells (EC) contain colony stimulating activity, Both UCCM and ECCM were partially purified by DEAE-Sepharose and ACA44 gel filtration chromatography. The molecular weights were estimated as 25,000 and 31,000 for UC-CSF and EC-CSF, respectively. UC-CSF was further fractionated by Con A Sepharose, IEF and HPLC on a hydrophobic phenyl column. The highly purified CSF stimulates human macrophage and granulocyte colony formation, indicating it is GM-CSF in nature. Characterization studies have revealed that both CSFs are heat stable at 60°C for 30 min. They are sensitive to digestion by protease and to periodate oxidation but are stable to treatment with sulfhydryl reagents. The synthesis of CSF in endothelial cells is inhibited by actinomycin D, cycloheximide and puromycin, indicating that protein and RNA synthesis are required for CSF production. Among the mitogens tested, only LPS exhibited stimulatory activity on the production of CSF. Metabolic modulators such as dibutyryl cAMP, isobutylmethylxanthine, PGE2 and lactoferrin inhibit CSF production, while PGF2 enhances CSF production.

In this study, the production of monoclonal antibodies directed against the activating enzyme for an S6 kinase is examined and described. Evidence is presented for the association of an Mr. 55,000 abd Mr. 95,000 protein with the s6 kinase. These proteins are phosphorylated in the presence of Activating Enzyme. A sequence of regulatory events for insulin-stimulated phosphorylation of ribosomal protein S6 in cells is postulated as follows: insulin activates the receptor tyrosine kinase, which phosphorylates the Mr 116,000 subunit of Activating Enzyme. The Activating Enzyme then activates the S6 kniase by phosphorylation, and phosphorylation of the ribosomal protein s6 is promoted.

Human colony-stimulating factor-1 (CSF-1) was purified from the serum-free conditioned medium of a human pancreatic carcinoma cell line. The four-step procedure included chromatography on DEAE Sepharose, Con A Sepharose and HPLC on phenyl column and reverse-phase C-3 column. The purity of human CSF-1 was demonstrated by sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS—PAGE) as a single diffuse band with a molecular weight (Mr) of 42,000-50,000 and was further confirmed by a single amino-terminal amino acid residue of glutamate. Under reducing conditions, purified CSF-1 appeared on SDS-PAGE as a single protein band with a Mr of 21,000-25,000 and concurrently lost its biological activity, indicating that human CSF-1 consists of two similar subunits and that the intact quaternary structure is essential for biological activity. When treated with neuraminidase and endo-8~D~N—acetylglucosaminidase D, the Mr of CSF-1 was reduced to 36,000-40,000 and to a Mr of 18,000-20,000 in the presence of mercaptoethanol.