Sampling for Explosives-Residues at Fort Greely,Alaska

Fort Greely, Alaska has an extensive complex of weapon training and testing areas located on lands withdrawn from the public domain under the Military Lands Withdrawal Act (PL106-65). The Army has pledged to implement a program to identify possible munitions contamination. Because of the large size (344,165,000 m²) of the high hazard impact areas, characterization of these constituents will be difficult. We used an authoritative sampling design to find locations most likely to contain explosives-residues on three impact areas. We focused our sampling on surface soils and collected multi-increment and discrete samples at locations of known firing events and from areas on the range that had craters, pieces of munitions, targets, or a designation as a firing point. In the two impact areas used primarily by the Army, RDX was the most frequently detected explosive. In the impact area that was also used by the Air Force, TNT was the most frequently detected explosive. Where detected, the explosives concentrations generally were low (<0.05 mg/kg) except in soils near low-order detonations, where the explosive-filler was in contact with the soil surface. These low-order detonations potentially can serve as localized sources for groundwater contamination if positioned in recharge areas.     

Systematics within Gyps vultures: a clade at risk

Background  

Populations of the Oriental White-backed Vulture (Gyps bengalensis) have declined by over 95% within the past decade. This decline is largely due to incidental consumption of the non-steroidal anti-inflammatory veterinary pharmaceutical diclofenac, commonly used to treat domestic livestock. The conservation status of other Gyps vultures in southern Asia is also of immediate concern, given the lack of knowledge regarding status of their populations and the continuing existence of taxonomic uncertainties. In this study, we assess phylogenetic relationships for all recognized species and the majority of subspecies within the genus Gyps. The continuing veterinary use of diclofenac is an unknown but potential risk to related species with similar feeding habits to Gyps bengalensis. Therefore, an accurate assessment of the phylogenetic relationships among Gyps vultures should aid in their conservation by clarifying taxonomic uncertainties, and enabling inference of their respective relatedness to susceptible G. bengalensis.     

The mannoprotein of Saccharomyces cerevisiae is an effective bioemulsifier

The mannoprotein which is a major component of the cell wall of Saccharomyces cerevisiae is an effective bioemulsifier. Mannoprotein emulsifier was extracted in a high yield from whole cells of fresh bakers' yeast by two methods, by autoclaving in neutral citrate buffer and by digestion with Zymolase (Miles Laboratories; Toronto, Ontario, Canada), a beta-1,3-glucanase. Heat-extracted emulsifier was purified by ultrafiltration and contained approximately 44% carbohydrate (mannose) and 17% protein. Treatment of the emulsifier with protease eliminated emulsification. Kerosene-in-water emulsions were stabilized over a broad range of conditions, from pH 2 to 11, with up to 5% sodium chloride or up to 50% ethanol in the aqueous phase. In the presence of a low concentration of various solutes, emulsions were stable to three cycles of freezing and thawing. An emulsifying agent was extracted from each species or strain of yeast tested, including 13 species of genera other than Saccharomyces. Spent yeast from the manufacture of beer and wine was demonstrated to be a possible source for the large-scale production of this bioemulsifier.     

Protamine sulfate inhibits mitogenic activities of the extracellular matrix and fibroblast growth factor, but potentiates that of epidermal growth factor

Protamine sulfate, an inhibitor of angiogenesis in vivo, markedly inhibits the ability of angiogenic factors such as acidic or basic fibroblast growth factor (aFGF, bFGF) to stimulate the proliferation in vitro of either BHK-21 cells or vascular endothelial cells. The inhibition is reversible, and cells remain viable even after prolonged exposure to protamine sulfate. Protamine sulfate inhibits the mitogenic effects of both growth factors by preventing them from binding to their common cell surface receptors. It also inhibits the mitogenic activity of the extracellular matrix produced by bovine corneal endothelial cells. This substrate has been shown in previous studies to replace the requirement for FGF of many cell types. In contrast, protamine sulfate potentiates the mitogenic activity of epidermal growth factor (EGF). This indicates that protamine sulfate also acts at cellular sites which are not associated with FGF receptors.     

Immortalization of human fibroblasts transformed by origin-defective simian virus 40.

Simian virus 40 (SV40)-mediated transformation of human diploid fibroblasts has provided an effective experimental system for studies of both "senescence" in cell culture and carcinogenesis. Previous interpretations may have been complicated, however, by the semipermissive virus-cell interaction. In earlier studies, we previously demonstrated that the human diploid fibroblast line HS74 can be efficiently transformed by DNA from replication-defective mutants of SV40 containing a deletion in the viral origin for DNA synthesis (SVori-). In the current study, we found that such SVori- transformants show a significantly increased life span in culture, as compared with either HS74 or an independent transformant containing an intact viral genome, but they nonetheless undergo senescence. We have clonally isolated six immortalized derivatives of one such transformant (SV/HF-5). Growth studies indicate that the immortalized cell lines do not invariably grow better than SV/HF-5 or HS74. Genetic studies involving karyotypic analysis and Southern analysis of integrated viral sequences demonstrated both random and nonrandom alterations. All immortalized derivatives conserved one of the two copies of SV40 sequences which expressed a truncated T antigen. These cloned SV40-transformed cell lines, pre- and postimmortalization, should be useful in defining molecular changes associated with immortalization.     

Degradation of fluorene in soil by fungus Phanerochaete chrysosporium

During investigation of biodegradation in soil, we have found that classical or standard techniques for introduction of compounds and the growth of fungus into soil are ill-defined and inadequate. In response to this deficiency, a method for controlled introduction of extractable compounds and for the growth of fungus in soils has been developed. This method was successfully used to study the degradation of fluorene in soil by the fungus Phanerochaete chrysosporium.     

Point mutations in the 23 S rRNA genes of four lincomycin resistant Nicotiana plumbaginifolia mutants could provide new selectable markers for chloroplast transformation

Summary Experiments designed to establish stable chloroplast transformation require selectable marker genes encoded by the chloroplast genome. The antibiotic lincomycin is a specific inhibitor of chloroplast ribosomal activity and is known to bind to the large ribosomal subunit. We have investigated a defined region of the chloroplast 23 S rRNA genes from four lincomycin resistant Nicotiana plumbaginifolia mutants and from wild-type N. plumbaginifolia. The mutants LR415, LR421 and LR446 have A to G transitions at positions equivalent to the nucleotides 2058 and 2059 in the Escherichia coli 23 S rRNA. The mutant, LR400, possesses a G to A transition at a position corresponding to nucleotide 2032 of the E. coli 23 S rRNA.