Production of Gliotoxin in Unsterilized Soil
IT has long been recognized that microbial antagonisms exist in the soil, and the possibility that this might be due to production of antibiotics has been suggested although never actually proved.
Importance of antibiotic production in antagonism of selected Streptomyces species to two soil-borne plant pathogens.
Antagonism of ten Streptomyces spp., five of which produce antibiotics, to the plant pathogens Rhizoctonia solani and Phytophthora megasperma var. sojae was studied. Antibiotic activity was detected in culture for the five antibiotic producers. S. griseus, S. hygroscopicus var. geldanus, and S. noursei produced wide zones of inhibition to R. solani and P. megasperma var. sojae. Similar activity was found for S. reticuli var. protomycicus to P. megasperma var. sojae. S. cellulosae reduced Rhizoctonia root rot on pea when sterile soil was infested simultaneously with the antagonist and R. solani. S. hygroscopicus gave almost complete disease control when the streptomycete was added 7 days prior to infesting the soil with R. solani. Several of the Streptomyces spp. reduced Phytophthora root rot on soybean when the streptomycetes were added to soil at the same time as P. megasperma var. sojae or 7 days prior to adding the pathogen. S. herbaricolor and S. coeruleofuscus gave the most consistent control. No relationship was found between reported antibiotic activity or antagonism on agar media and reduction in disease severity. Only S. hygroscopicus var. geldanus gave both control of Rhizoctonia root rot and large zones of inhibition on agar media when the streptomycetes were preincubated in soil for 7 days.
Complications of motility peg placement for porous hydroxyapatite orbital implants
Aim: To evaluate the complications associated with pegging of porous hydroxyapatite orbital implants. Methods: Complications associated with pegging were retrospectively reviewed from the charts of 100 of 133 patients with hydroxyapatite implantation from 1993 to 2000. Results: 48 (48%) of the 100 hydroxyapatite implanted patients who had undergone pegging were found to have problems with their pegs, including discharge (45.8%), peg falling out (20.8%), pyogenic granulomas (16.7%), popping peg (14.6%), hydroxyapatite visible around peg hole (8.3%), part of peg shaft visible (6.2%), peg drilled off centre (6.2%), peg drilled at an angle (4.2%), and excess movement of peg (4.2%). The standard peg fell out statistically more often than the peg and sleeve system (Yates's corrected χ2, p=0.038). There was a trend towards complications of the peg with use of a standard peg (versus sleeved peg) (p=0.226). Conclusions: There are several potential complications of pegging. Most complications are minor and can be managed successfully.