Expression of Polyoma-induced Transplantation Antigen in Hybrid Cell Lines

The polyoma-induced transplantation antigen is virus specific and its presence on polyoma transformed but not normal cells suggested that at least part of the polyoma genome is maintained in tumour cells. Studies reported here indicate that malignancy is not maintained solely by the presence of this transplantation antigen.     

Host Cell Reactivation in Strains of <Emphasis Type="Italic">E. coli</Emphasis> lacking DNA Polymerase Activity <Emphasis Type="Italic">in vitro</Emphasis>

BACTERIAL cells can repair DNA which has been damaged by irradiation with ultraviolet light (UV). A repair process which does not depend on light is known as dark reactivation. Because the cells can repair damaged infecting DNA, as well as their own by the same mechanism the phenomenon has also been called host cell reactivation (HCR). HCR seems to consist of the following reaction steps¹: (1) endonucleolytic incision close to the UV photoproduct which most frequently is a pyrimidine dimer; (2) excision of the photoproduct as an oligonucleotide; (3) resynthesis of the removed nucleotide sequence using the opposite strand as a template; and (4) rejoining of the polynucleotide chains.     

Induction of the Feline Oncornavirus Associated Cell Membrane Antigen in Human Cells

BY N-terminal amino-acid sequence analysis, Glenner et al.¹ have shown that amyloid fibrils are very similar to the variable part of an immunoglobulin kappa light chain (Bence-Jones protein Ker) and they suggested that amyloid is constituted by immunoglobulin light chains.     

Starch and Sugar in Canes of Summer-Pruned Vitis vinifera Plants

Plants of Vitis vinifera, var. Chasselas Doré were summer-prunedat various times after harvest in order to secure a second,winter crop. Dry weight, starch content, reducing sugar andnon-reducing sugar-content in canes of such treated plants weredetermined from July 1953 until February 1954. As controls,normally winter-pruned plants were used. Highest fertility was found in the latest-pruned plants, whichalso gave the largest yields. The earliest-pruned plants hadthe lowest fertility and gave the smallest crop. Dry weight in the controls was highest during September, anddropped somewhat during January and February. In the summer-prunedvines dry weight decreased immediately after pruning and roseagain at the time of the termination of the induced growth-period. Starch-content in the controls increased strongly from the timeof beginning of the experiments until November, decreased afterwardsand rose again in January. Starch-content of all the treatedvines, independently of time of summer pruning, followed mostlythe trend of the starch-content of the controls, but differedfrom it by being at a minimum in November and by not risingin January. The trend in the reducing and non-reducing sugar-content issimilar in the treated and non-treated plants. However, thereis always a temporary decrease in sugar immediately after thepruning. In all the plants there was an increase in the reducingsugars in February and at the same time a decrease in the non-reducingsugar. No starch-sugar conversion could be found during thewinter period.