Serum S-100beta as a possible marker of blood-brain barrier disruption.

Two brain-specific proteins, S-100beta and neuron-specific enolase (NSE), are released systemically after cerebral lesions, but S-100beta levels sometimes rise in the absence of neuronal damage. We hypothesized that S-100beta is a marker of blood-brain barrier (BBB) leakage rather than of neuronal damage. We measured both proteins in the plasma of patients undergoing iatrogenic BBB disruption with mannitol, followed by chemotherapy.

Suppressive effect of met-enkephalin on bone marrow cell proliferation in vitro shows circadian pattern and depends on the presence of adherent accessory cells.

The cellularity of femoral bone marrow and the content of the granulocyte-macrophage colony forming cells (GM-CFC) were followed in mice between 0600 h and 1800 h. The cellularity increased at the beginning of the light period, and the GM-CFC content at the end. Opioid pentapeptide methionine-enkephalin reduced the GM colony forming ability of the bone marrow cell suspensions in proportion to the GM-CFC content.