Qualitative and quantitative changes of non-histone chromatin proteins of spleen cells during the primary immune response to sheep red blood cells and aggregated human gamma-globulin were described. Synthesis of non-histone chromatin proteins was measured by labelling with 3H-tryptophan during culture of spleen cells in vitro. Chromatin was isolated and labelled proteins were analysed by polyacrylamide gel electrophoresis. During the immune response to both antigens in chromatin of spleen cells three new fractions of non-histone chromatin proteins were synthesized: fractions F1 - M = 12 000 and H - M = 3 000, specific for sheep red blood cells and fractions I1 - M less than 3 000 and B - M = 120 000, specific for human gamma-globulin. The third antigen-non-specific fraction was synthesized at the time when the primary immune reaction was finishing. These new fractions were synthesized only in one of the analysed subpopulations of spleen cells. In thymocytes (non-fully-differentiated lymphoid cells) all these fractions were absent. Changes of non-histone chromatin proteins in thymocytes during the immune response were similar to those found during stimulation to proliferation by phytohemagglutinin in vitro.

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A 15-year-old girl with complex partial epilepsy had subdural electrodes implanted. She was tested on reaching tasks during electrocortical stimulation prior to neurosurgery. MRI showed left mesial parietal dysplasia. Stimulation of the superior parietal cortex (electrode pair 37-45, figure, A) during line bisection and visually guided reaching resulted in movement arrest followed by the arm drifting upward (figure, B, videos 1 and 2 on the Neurology ® Web site at www.neurology.org). Stimulation of these electrodes also resulted in reaching arrest when aiming toward proprioceptive targets (video 3). These observations are consistent with the idea that superior parietal cortex contains representations of defensive arm postures 1 or is involved in sensoryguided reaching.