delta-9-Tetrahydrocannabinol (THC) inhibition of the membrane transport system for thymidine]

THC decreases 3H-thymidine uptake within 15 sec. after addition of the drug to the culture (L1210 murine lymphoma cells and human lymphocytes). Experiments performed at 0 degrees C indicate that THC has no action on thymidine binding to the carrier. THC in micromolar concentration inhibits DNA synthesis through a alteration of membrane configuration.     

Separation of specific fractions of synaptosomes by affinity chromatography

Summary The authors describe a new technique for isolation of specific fractions of synaptosomes, on the basis of their surface glycoproteins, by affinity chromatography using lectin-Sepharose columns.     

Purification and structural characterisation of human HLA-linked B-cell antigens.

The human B cell-specific alloantigen which is closely linked genetically to HLA contains two non-covalently associated, sialogycoprotein subunits of molecular weight (MW) 29,000 (p29), and 34,000 (p34). Although p29 and p34 have different amino-terminal sequences, their tyrosine peptide maps indicate considerable similarity in other portions of their polypeptide chains. Thus the genes for their proteins may have evolved by duplication of a common ancestral gene. Another lymphocyte cell surface protein of MW 16,000 (p16) has also been characterised. Both p16 and p44 (the heavy chain of HLA-A,B antigens) have been compared with p29 and p34.     

Glutathione peroxidase in dried blood spots

Summary A new procedure utilizing dried blood spots was developed for detecting glutathione peroxidase deficiency. Samples from a known patient with a partial defect and from rats with an induced deficiency were distinguished from respective control groups by their longer defluorescence endpoints., Samples from 100 patients with anemia and 2 phenylketonuric infants on low-protein diets contained glutathione peroxidase activity similar to that in 82 controls, when screened for the enzyme defect by the new procedure.