Human peripheral blood in tissue culture and the action of phytohemagglutinin

Résumé Phytohémagglutinin a transformé en cultures brèves plus de 70% des petits lymphocytes de personnes normales, de nouveau-nés et d'hypo--globulinémiques en cellules blastoïdes, mais moins de 3% des lymphocytes de malades avec leucémie lymphatique chronique. L'action blastogénique existe dans l'absence erythrocyte-agglutinante. On discute la signification de ces découvertes.     

Nematicidal activity of secondary and tertiary alkyl amides and amines

Summary Several C₁₁ to C₁₅ amides and amines that disrupt growth in certain insects showed high nematicidal activity in direct contact tests. Two amides and 9 amines killedPanagrellus at 5–10 ppm. Of these, 1 amide and 3 amines killedMeloidogyne larvae at 20 ppm.Nematology Laboratory.Insect Physiology Laboratory.     

High frequency of BRAF mutations in nevi

To evaluate the timing of mutations in BRAF (v-raf murine sarcoma viral oncogene homolog B1) during melanocytic neoplasia, we carried out mutation analysis on microdissected melanoma and nevi samples. We observed mutations resulting in the V599E amino-acid substitution in 41 of 60 (68%) melanoma metastases, 4 of 5 (80%) primary melanomas and, unexpectedly, in 63 of 77 (82%) nevi. These data suggest that mutational activation of the RAS/RAF/MAPK pathway in nevi is a critical step in the initiation of melanocytic neoplasia but alone is insufficient for melanoma tumorigenesis.