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Populations of macro-algae and sessile invertebrates have precipitously declined in urbanised coastal waters in Australia since European occupation. Responses of healthy subtidal sessile assemblages to cumulative impacts and types of urban impacts were measured in one of the most polluted estuaries in Australia - the Derwent Estuary - by transplanting sessile communities established on pavers to locations adjacent to marinas, sewerage outfalls, fish farm cages, and stormwater discharges, each with associated controls. Reef communities translocated to sites adjacent to central urban pollution sources (within 5 km of Hobart) lost canopy-forming algae. Fish farms, marinas, and storm water drains were all characterised by higher filamentous algal cover than their controls. Marinas were associated with losses in canopy and foliose algae. Restoration of subtidal reef near highly urbanised areas is unlikely to be successful until current pollution levels are dramatically reduced., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Intensive fish culture in open sea pens delivers large amounts of nutrients to coastal environments. Relative to particulate waste impacts, the ecological impacts of dissolved wastes are poorly known despite their potential to substantially affect nutrient-assimilating components of surrounding ecosystems. Broad-scale enrichment effects of salmonid farms on Tasmanian reef communities were assessed by comparing macroalgal cover at four fixed distances from active fish farm leases across 44 sites. Macroalgal assemblages differed significantly between sites immediately adjacent (100m) to fish farms and reference sites at 5km distance, while sites at 400m and 1km exhibited intermediate characteristics. Epiphyte cover varied consistently with fish farm impacts in both sheltered and exposed locations. The green algae Chaetomorpha spp. predominated near fish farms at swell-exposed sites, whereas filamentous green algae showed elevated densities near sheltered farms. Cover of canopy-forming perennial algae appeared unaffected by fish farm impacts., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Sections of 51 surgically enucleated eyes from cases of retinoblastomas were examined immunohistochemically to delineate patterns of cellular differentiation. Employing the avidin-biotin immunoperoxidase technique, antibodies were used against glial fibrillary acidic protein (GFAP), S-100 protein and neuron specific enolase (NSE). Areas of uninvolved retina and/or optic nerve were used as built-in positive control. Most of the tumors showed GFAP and S-100 protein-positive perivascular glial cells that were interpreted as reactive astrocytes. In three well-differentiated retinoblastomas, glial cells were found to be interspersed randomly among tumor cells and not associated with blood vessels. These glial cells were interpreted as neoplastic based on their distribution pattern and cytologic features. In about half of the tumors, the retinoblastoma cells stained positively for NSE, indicating their neuronal tumor cells that stained positively for NSE but failed to show any evidence of photoreceptor differentiation. Based on these observations and similar differentiation patterns described in other primitive neuroectodermal tumors of the brain, it is suggested that retinoblastoma cells can differentiate not only into photoreceptor cells but also along other neuronal cell lines and rarely into glial cells.