Paramecium tetraurelia is a unicellular eukaryotic ciliate. Certain strains of paramecia have been shown to contain endosymbiotic bacteria. Furthermore, some of these endosymbiotic bacteria confer a killing ability on the host paramecia, known as killer paramecia, because the endosymbiont can be lethal to other paramecia, known as sensitive paramecia, if it is released into the environment. This death has been connected to a protein found within the P. tetraurelia known as an R body. Interestingly, the R body-related-death resembles apoptosis in that it causes membrane blebbing, a characteristic of apoptosis. Furthermore, paramecia contain another marker of apoptosis, a mechanism to degrade DNA which is used in normal paramecia conjugation. Therefore, exposure to the R body and toxin may be activating some existing pathways in the paramecia, leading to apoptosis. To determine whether the mode of cell death induced by the R bodies is apoptotic, a flow cytometer was used to examine DNA fragmentation, a characteristic of apoptosis, using a Terminal Deoxynucleotidyl Transferase Biotin-dUTP Nick End Labeling (TUNEL) assay. Three groups of paramecia were examined with TUNEL: sensitive-alone, killer-alone, and killer mixed with sensitive. The results of the TUNEL assay were inconclusive because the only cell group showing positive TUNEL staining was the sensitive paramecia group. This could possibly be due to the DNA degradation that occurs during normal cell conjugation. Therefore, this study was the first to use flow cytometry in order to examine R body induced cell death and provides a clear basis for further research.

Plant material has accumulated in the Poutwater Pond peat bog for thousands of years. The area has acid conditions and a thick (5 meter) accumulation of slowly decomposing plant material. The nature of the microbes living at different depths in this environment is not well known. Bacteria were isolated from a core collected at the peat bog and brought in to the laboratory. Samples from different depths were cultured on trypticase soy agar. A streak plate method was used to isolate some colonies of bacteria. The BIOLOG™ technique used for microbial community analysis showed that the assemblage of microorganisms remains similar at different depths of the peat bog. Gram staining showed that both Gram negative and Gram positive rods were cultured from different depths of the peat bog. The BIOLOG™ identification system was used to identify four of the bacteria as Pseudomonas chlororaphis, P. fluorescens, Bacillus mycoides and Alcaligenes denitrificans. Some bacteria have been tested for antibiotic susceptibility. Bacteria demonstrating antibiotic resistance occur at different depths of the peat bog. The results of this study are useful in understanding the organisms that live under these conditions.

Silver has a long historical use as an antimicrobial metal; it exerts its antimicrobial effects oligodynamically. Current silver-fabric technologies are dependent upon either the use of silver thread in the weave or time release of silver salts from fabrics. Electron-beam technology uses a concentrated beam of electrons to induce crosslinking in irradiated materials. This research marks experimental work attempting to bond silver directly to cloth to create a composite. The study had four aims, to: 1) test treated synthetic fabrics for antimicrobial effectiveness; 2) distinguish differences in resistance between different bacterial genera; 3) test the longevity of treated fabrics through repeated washing; and 4) identify treatment conditions producing maximum effectiveness. Fabric was immersed in silver nitrate solution then irradiated to incite deposition. Effectiveness was measured using a Kirby-Bauer procedure to measure zones of inhibition around irradiated cloth circles. Following each round of assay, fabrics were laundered and the process repeated to gauge the effectiveness of the fabric in retaining antimicrobial activity. Data analysis demonstrated no significant differences in inhibition between gram positive and gram negative genera nor in irradiation dosages. Composites treated with silver nitrate but not irradiated lost antimicrobial properties after the initial washing, suggesting no fabric-metal bonding. However, the antimicrobial properties of the treated samples lessened after the initial washing but thereafter remained steady through the experimental period.

The extracellular matrix is synthesized predominantly by fibroblasts and gives tissue its structural integrity. It is remodeled by ultraviolet radiation via the increased expression/activities of matrix metalloproteinases (MMP) and inhibition of the tissue inhibitors of matrix metalloproteinases (TIMP). On the other hand, transforming growth factor-β (TGF-β) stimulates extracellular matrix deposition. The hypothesis of the research was the counteraction of UV radiation effects on fibroblasts by a TGF-β inducing agent (AT). Non-irradiated and UVB radiated fibroblasts were exposed to AT and examined for MMP-1 promoter activity, and expression of MMP-2, TIMP-1, and TIMP-2. AT inhibited MMP-1 promoter activity and dramatically stimulated MMP-2 expression; its effects were antagonized by UV radiation. The dramatic stimulation of TIMPs by AT predominated in non-irradiated and UV irradiated fibroblasts. TGF-β induction in fibroblasts is therefore an effective strategy to counteract UV radiation induced damage to the extracellular matrix, particularly through the induction of TIMPs.

Asclepias tuberosa L., or butterflyweed, is a native plant species occurring throughout much of North America, and is a valued horticultural plant most known for its ability to attract butterflies. Three subspecies, A.t. interior, A.t. rolfsii, and A.t. tuberosa, have been identified based on leaf shape, but their overall genetic variability is not known. The current study investigated the genetics of this plant from populations located in six different geographic areas in the United States. Because there is very little knowledge of the genetics of this plant, as a first approach, analyses based on ISSR polymorphisms were used to determine genetic structure. A total of 115 ISSR bands, of which 96.5% were polymorphic, were scored from 82 samples. The Exact Test for population differentiation showed that populations from all six geographic locations were genetically distinct from one another. UPGMA analysis determined that the populations from the different geographic locations did not cluster into three different groups representing the three subspecies. These results do not support the separation of A. tuberosa into three subspecies. Instead, they suggest that each of the individual populations studied are relatively genetically isolated. However, there is potential for gene flow, which may allow the populations of A. tuberosa to maintain variability.