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Polycyclic aromatic hydrocarbons (PAHs) are common contaminants in terrestrial and aquatic environments and can represent a significant constituent of the carbon pool in coastal sediments. We report here the results of an 18-month seasonal study of PAH biodegradation and heterotrophic bacterial production and their controlling biogeochemical factors from 186 sediment samples taken in a tidally influenced freshwater estuary. For each sampling event, measurements were averaged from 25-45 stations covering ∼250 km². There was a clear relationship between bacterial production and ambient temperature, but none between production and bottom water dissolved oxygen (DO) % saturation or PAH concentrations. In contrast with other studies, we found no effect of temperature on the biodegradation of naphthalene, phenanthrene, or fluoranthene. PAH mineralization correlated with bottom water DO saturation above 70% (r² > 0.99). These results suggest that the proportional utilization of PAH carbon to natural organic carbon is as much as three orders of magnitude higher during cooler months, when water temperatures are lower and DO % saturation is higher. Infusion of cooler, well-oxygenated water to the water column overlying contaminated sediments during the summer months may stimulate PAH metabolism preferentially over non-PAH organic matter. [ABSTRACT FROM AUTHOR]

This proceeding presents experiments demonstrating that BioLPTM, Biological Laser Printing, can be used to rapidly and accurately print individual cells as well as patterns of cells in three dimensions. Human osteosarcoma cells were deposited into a biopolymer matrix, and after twenty-four hours of incubation, the printed cells remained viable and had multiplied. Multiple layers of human osteosarcoma cells were transferred into a MatrigelTM substrate, producing a three-dimensional cellular construct. Live/dead assays were performed, demonstrating that greater than 95% of the cells were viable after the being printed into the biopolymer. The ability to selectively print individual cells has potential benefits for cell selection studies and genomics and proteomics research. In addition, this technique could enable layers of tissue scaffolding to be seeded with cells at exceedingly high precision and resolution. [ABSTRACT FROM AUTHOR]

Specimens of kidney, heart, lung, eye, skin, conjunctiva, choroid plexus and brain were obtained from a patient with systemic lupus erythematosus (SLE) post-mortem. The tissues were examined for immune-complex deposition by direct immunofluorescence utilizing antisera specific for IgG, IgA, IgE, IgM and the complement components Clq and C3. Tissues were also examined for C-type viral antigen by indirect immunofluorescence with an antisera raised to HEL-12 virus. Immune complexes were detected along basement membranes and/or in vessel walls of kidney, heart, lung, skin, conjunctiva and eye. HEL-12 viral antigen was detected in the same distribution as immunoglobulins and complement in all tissues. Preimmune serum did not mediate immunofluorescence and the reaction mediated by the anti-HEL-12 virus serum could be blocked by absorption with purified viral antigens. Two renal biopsies were obtained from a second SLE patient during clinical exacerbation and remission. Immunofluorescence analysis of the biopsy obtained during exacerbation showed 3 + deposition of immunoglobulin, complement and HEL-12 viral antigen. In contrast, the biopsy obtained 6 months later during remission showed trace -1 + immunofluorescence for HEL-12 viral antigen, immunoglobulin and complement. We conclude that HEL-12 viral antigen is a component of widely disseminated immune complexes in SLE, and that the disappearance of HEL-12 viral antigen occurs concomitantly with the loss of immune deposits. [ABSTRACT FROM AUTHOR]