Radiation-induced volatile hydrocarbon production in platelets

Generation of volatile hydrocarbons (ethane, pentane) as a measure of lipid peroxidation was followed in preparations from platelet-rich plasma irradiated in vitro. The hydrocarbons in the headspace of sealed vials containing irradiated and nonirradiated washed platelets, platelet-rich plasma, or platelet-poor plasma increased with time. The major hydrocarbon, pentane, increased linearly and significantly with increasing log radiation dose, suggesting that reactive oxygen species induced by ionizing radiation result in lipid peroxidation. Measurements of lipid peroxidation products may give an indication of suboptimal quality of stored and/or irradiated platelets.     

Direct observation of cell wall glucans in whole cells of Saccharomyces cerevisiae by magic-angle spinning 13C-nmr

Intact cells of Saccharomyces cerevisiae were examined as an aqueous paste by ¹³C-nmr spectroscopy with direct polarization and magic-angle spinning. The spectra obtained were highly resolved, showing numerous resonances in the 60-105 ppm range that were assigned to carbons of a liquid-like domain of the cell wall glucan. Assignments were confirmed by running the spectrum of S. cerevisiae in which the cell wall glucans were labeled with [¹³C] by feeding the cell [¹³C ] galactose. The spectra indicate that the glucan in the cell wall of intact S. cerevisiae assumes a helical conformation and suggest that strain 17A fed with galactose preferentially incorporates the resulting glucose into β(1 → 3)-linkages. © 1994 John Wiley & Sons, Inc.     

Polyadenylate-protein complexes in resting and growing 3T3 cells.

The properties of the ribonuclease resistant cytoplasmic ribonucleoprotein particles were studied in contact-inhibited and serum induced proliferating 3T3 cells. The RNP particles were fractionated by oligo (dT)-cellulose chromatography and banded in CsSO4 gradients. The main RNP fraction, eluted with 25% formamide, contained the major ribonuclease resistant RNA sequences in both resting and growing cells. The protein component of this fraction had a molecular weight of about 72,000 in contact-inhibited cells and 81,000 in serum induced cells.