Effects of variations in nitrogen and carbon sources on the physiology of growth of erynia radicans,a potential mycoinsecticide

Summary The potentially insecticidal fungusErynia radicans has been grown on a synthetic medium, with urea as N source, and on different glucose/yeast extract media, and the latter have been optimised in relation to biomass yield and growth rate.     

Gamma-ray induced inhibition of DNA synthesis in ataxia telangiectasia fibroblasts is a function of excision repair capacity

The extent of the deficiency in γ-ray induced DNA repair synthesis in an ataxia telangiectasia (AT) human fibroblast strain was found to show no oxygen enhancement, consistent with a defect in the repair of base damage. Repair deficiency, but not repair proficiency, in AT cells were accompanied by a lack of inhibition of DNA synthesis (replicon initiation) neither γ-rays or the radiomimetic drug bleomycin. Experiments with 4-nitroquinoline 1-oxide indicated that lack of inhibition was specific for radiogenic type damage. Thus excision repair, perhaps by DNA strand incision or chromatin modification, appears to halt replicon initiation in irradiated repair proficient cells whereas in repair defective AT strains this putatively important biological function is inoperative.     

Value of gallium scanning in seminoma of the testis.

Whole-body scanning using gallium-67-citrate gave consistently accurate tumour localisation in patients with seminoma of the testis. Thirteen out of 15 scans performed in patients with disseminated seminoma in relapse gave good imaging in all disease areas. Scans in patients with teratoma of the testis were less consistently positive; of nine scans performed in patients with disseminated teratoma seven were entirely negative and two scans lightly imaged large disease masses in two patients. In eight patients with combined (seminoma and teratoma) tumours the scan seemed to reflect the dominant tumour type at the time of scanning. In one of these patients the scans changed from positive to negative, being positive when seminoma was the dominant tumour and negative when a teratoma developed. Gallium-67-citrate scanning is useful in managing seminoma of the testis, both for determining the extent of disease present at initial presentation and for routine follow-up. It may be useful in the differential diagnosis of combined tumours when tumour masses are greater than 2 cm in diameter.     

Release of chemical mediators from partially purified human lung mast cells.

Human lung mast cells dispersed by enzymatic digestion of human lung fragments were concentrated to greater than 50% purity by sedimentation in isopycnic and velocity gradients. The dispersed lung mast cells had a characteristic ultrasturctural appearance including granules with a scroll or reticular structural appearance including granules with a scroll or reticular structure surrounded by perigranular membranes. Histamine and preformed eosinophilotactic activity sedimented with mast cells on isopycnic gradients, and mast cells and these mediators were separated from the bulk of the other lung cells after velocity gradient sedimentation. The histamine content of isolated lung mast cells was calculated to range from 1.0 to 5.5 pg/cell. The quantity of SRS-A generated with anti-IgE or specific antigen was relatively limited but confined to the mast cell-rich fractions and associated with release of histamine and eosinophilotactic activity.