Metastatic epidural spinal cord compression: current concepts and treatment

Metastatic epidural spinal cord compression (MESCC) is a medical emergency complicating the course of 5–10% of patients with cancer [1]. When diagnosis and treatment is early with the patient ambulatory prognosis for continued ambulation is good [2]. If the patient is nonambulatory or paraplegic, prognosis for meaningful recovery of motor and bladder function is markedly decreased. In the last decade, significant advances in the understanding, management and treatment of metastatic epidural spinal cord compression have occurred.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45378/1/11060_2005_Article_BF01051052.pd

Survivorship of seedlings of false sandalwood (Myoporum platycarpum) in the chenopod rangelands grazed by sheep, kangaroos and rabbits at Whyalla, South Australia

Myoporum platycarpum R. Br. (Myoporaceae) is widely distributed through semi-arid New South Wales, South Australia, Western Australia and Victoria, where it occurs as an upper-storey dominant or co-dominant tree over chenopod shrublands. Previous studies have concluded that the seedlings and juveniles of many shrubs and trees, including M. platycarpum, are selectively grazed by sheep and rabbits, which threatens their long-term survival in rangelands. The aim of this study was to assess the survivorship of M. platycarpum seedlings grazed by sheep and rabbits in a rangeland setting. Seedlings of M. platycarpum were raised in the greenhouse and planted in the field and individually fenced to allow or prevent access by various herbivores. Over 1 year, the frequency of grazing and size of canopy was recorded. A flexible mixed model incorporating cubic smoothing splines was used to describe the relationship between change in canopy volume over time, fixed effects (exclosure type, time, rainfall and egesta weights) and random variability among plants, replicates and sites. The mixed models showed that there were no significant differences in canopy volume over time between sheep and rabbit-proof exclosures, indicating that rabbits were not significantly affecting the seedlings, browsing only five of those available to them, of which three survived. Large herbivores (sheep and/or kangaroos) grazed un-caged seedlings, resulting in significantly smaller canopy volumes, and higher death rates (80%). Although supplementary irrigation was applied, background losses due to desiccation in caged seedlings were up to 50%

Patch dynamics in grazed subtropical native pastures in south-east Queensland

Patch formation is common in grazed grasslands but the mechanisms involved in the formation and maintenance of patches are not clear. To increase our knowledge on this subject we examined possible reasons for patch formation and the influence of management on changes between patch states in three experiments in native pasture communities in the Crows Nest district, south-east Queensland. In these communities, small-scale patches (tall grassland (dominated by large and medium tussock grasses), short swards (dominated by short tussock grasses and sedges), and lawns (dominated by stoloniferous and/or rhizomatous grasses)) are readily apparent. We hypothesized that the formation of short sward and lawn patches in areas of tall grassland was due to combinations of grazing and soil fertility effects. This was tested in Experiment 1 by applying a factorial combination of defoliation, nutrient application and transplants of short tussock and stoloniferous species to a uniform area of tall grassland. Total species density declined during the experiment, was lower with high nutrient applications, but was not affected by defoliation. There were significant changes in abundance of species that provided support for our hypotheses. With light defoliation and low nutrients, the tall grassland remained dominated by large tussock grasses and contained considerable amounts of forbs. With heavy defoliation, the pastures were dominated by medium tussock grasses and there were significant decreases in forbs and increases in sedges (mainly with low nutrients) and stoloniferous grasses (mainly with high nutrients). Total germinable seed densities and those of most species groups were significantly lower in the heavy defoliation than the light defoliation plots. Total soil seed numbers were not affected by nutrient application but there were fewer seeds of the erect forbs and more sedge seeds in plots with high nutrients. The use of resting from grazing and fire to manage transitions between patches was tested. In Experiment 2, changes in species density and abundance were measured for 5 years in the three patch types with and without grazing. Experiment 3 examined the effects of fire, grazing and resting on short sward patches over 4 years. In Experiment 2, total species density was lower in lawn than short sward or tall grassland patches, and there were more species of erect forbs than other plant groups in all patch types. The lawn patches were originally dominated by Cynodon spp. This dominance continued with grazing but in ungrazed patches the abundance of Cynodon spp. declined and that of forbs increased. In the short sward patches, dominance of short tussock grasses continued with grazing but in ungrazed plots their abundance declined while that of large tussock grasses increased. The tall grassland patches remained dominated by large and medium tussock species. In Experiment 3, fire had no effect on species abundance. On the grazed plots the short tussock grasses remained dominant but where the plots were rested from grazing the small tussock grasses declined and the large tussock grasses increased in abundance. The slow and relatively small changes in these experiments over 4 or 5 years showed how stable the composition of these pastures is, and that rapid changes between patch types are unlikely