Genetic controls of meiotic recombination and somatic DNA metabolism in Drosophila melanogaster

Recombination-defective meiotic mutants and mutagen-sensitive mutants of D. melanogaster have been examined for their effects on meiotic chromosome behavior, sensitivity to killing by mutagens, somatic chromosome integrity, and DNA repair processes. Several loci have been identified that specify functions that are necessary for both meiotic recombination and DNA repair processes, whereas mutants at combination and DNA repair processes, whereas mutants at other loci appear to be defective in only one pathway of DNA processing.     

Screening of Indian plants for biological activity: Part VII--Spermicidal activity of Indian plants

Extracts of about 1600 Indian plants were tested for spermicidal activity. A small quantity of rat vasal or epididymal contents was placed on 2 drops of plant solution, mixed, and examined under a phase contrast microscope. Results were scored positive if 100% of spermatozoa became immotile. Tests were repeated 3 times. and sperm revival tested by addition of buffer to the immobilized sperm sample. Plant extracts showing positive activity were tested on liquified human semen. 30 plants showed spermicidal activity in rats, of which 16 caused instantaneous immobilization of human spermatozoa. Studies are underway on the isolation of active constituents and subsequent structural relationships.