Disappearance Of The Natural Emergent 3-Dimensional Oyster Reef System Of The James River, Virginia, 1871-1948

Anecdotal reports have long indicated that oysters, Crassostrea virginica (Gmelin), in the Chesapeake Bay once grew in large 3-dimensional reef structures. However, hard evidence of widespread 3-dimensional oyster reefs in the Chesapeake Bay has been scarce. This study uses data collected from historic charts of the James River, one of the most productive oyster producing tributaries of the Chesapeake Bay, to examine the natural occurrence of these reefs as well as their destruction. An early series of charts from the 1870s clearly documents widespread emergent oyster reefs in the James River from Burwell\u27s Bay to Newport News Point. They were long, fairly wide, and shoal-like and oriented at right angles to the current. A 1940s series of charts indicates that by this time nearly all of these reefs had become submerged. Paired t-tests indicate a significant decrease in reef height and volume but not in reef area. This suggests that oysters and shell have been physically removed from the reefs. This likely had a major impact on water circulation patterns over and around the reefs, which may also have further adversely affected oyster populations

Gyrodactylus salinae n. sp. (Platyhelminthes: Monogenea) infecting the south European toothcarp Aphanius fasciatus (Valenciennes) (Teleostei, Cyprinodontidae) from a hypersaline environment in Italy

Background: Historically, non-native species of Gambusia (Poeciliidae) have been used to control larval stages of the Asian tiger mosquito, Stegomyia albopicta Reinert, Harbach et Kitching, 2004 throughout Italy. The potential utility of indigenous populations of Aphanius fasciatus (Valenciennes) (Teleostei: Cyprinodontidae) as an appropriate alternative biological control is currently being explored. A sub-sample of ten fish collected from Cervia Saline, Italy (salinity 65 ppt; 30°C) to assess their reproductive capability in captivity, harboured a moderate infection of Gyrodactylus von Nordmann, 1832 (Platyhelminthes, Monogenea). A subsequent morphological and molecular study identified this as being a new species. Results: Gyrodactylus salinae n. sp. is described from the skin, fins and gills of A. fasciatus. Light and scanning electron microscopical (SEM) examination of the opisthaptoral armature and their comparison with all other recorded species suggested morphological similarities to Gyrodactylus rugiensoides Huyse et Volckaert, 2002 from Pomatoschistus minutus (Pallas). Features of the ventral bar, however, permit its discrimination from G. rugiensoides. Sequencing of the nuclear ribosomal DNA internal transcribed spacers 1 and 2 and the 5.8S rRNA gene and a comparison with all species listed in GenBank confirmed they are unique and represent a new species (most similar to Gyrodactylus anguillae Ergens, 1960, 8.3% pair-wise distance based on 5.8S+ITS2). This represents the first species of Gyrodactylus to be described from Aphanius and, to date, has the longest ITS1 (774 bp) sequenced from any Gyrodactylus. Additional sampling of Cervia Saline throughout the year, found G. salinae n. sp. to persist in conditions ranging from 35 ppt and 5°C in December to 65 ppt and 30°C in July, while in captivity a low level of infection was present, even in freshwater conditions (0 ppt). Conclusions: The ability of G. salinae n. sp. to tolerate a wide range of salinities and temperatures shows its potential to readily adapt to several environmental conditions. These findings, together with the fact that A. fasciatus is a protected species and is considered as a biological control organism, necessitate further studies on the ecology and virulence of G. salinae n. sp

The effect of rhGM-CSF on the proliferation of osteogenic sarcoma cells

Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) promotes the growth of a variety of hematopoietic and nonhematopoietic cells, both benign and malignant. There is now evidence that osteoblast-like cells produce GM-CSF and their growth is stimulated by this cytokine in vitro. We have studied the effect of rhGM-CSF on DNA synthesis and cell proliferation in the human osteogenic sarcoma cell lines U-20S, G-292, MG-63, and HOS. RhGM-CSF stimulated a dose-dependent increase in radioactive thymidine incorporation in each of the four cell lines in the presence of serum-free media, and in two cell lines (HOS and U-20S) in the presence of fetal bovine serum (FBS). In addition, rhGM-CSF produced significant increases in cell proliferation in two cell lines (MG-63 and U-20S) in the presence of 2% FBS. These results suggest that GM-CSF may have an important role in the biology of human osteogenic sarcoma cells. The clinical implications of these findings merit further investigation