Scholarly Commons: Recent submissions
Now showing items 41-60 of 6287
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Regulating Effects of 11-Deoxycorticosterone on 3beta-Hydroxysteroid DehydrogenaseRegulating Effects of 11-Deoxycorticosterone on 3 beta-Hydroxysteroid Dehydrogenase Progesterone plays a key role in ovulation and the formation of a corpus luteum, although its regulation remains poorly understood. The enzyme 3/J-hydroxysteroid dehydrogenase (3/iHSD) converts pregnenolone to progesterone and thus represents a critical step in progesterone biosynthesis. It has recently been discovered that the primate ovary synthesizes 11-deoxycorticosterone (DOC) in response to an ovulatory gonadotropin stimulus. Blockade of the mineralocorticoid receptor (MR), which serves as the receptor for DOC, prevents gonadotropin-induced progesterone synthesis. It is hypothesized that DOC augments the expression of 3/HSD following an ovulatory stimulus via MR-mediated mechanisms. The current studies were to determine if 3/iHSD is an MR target gene in H295R adrenocortical cells, which are used as a surrogate model of primate ovarian steroidogenesis. The results indicate that an increase in 3^HSD RNA is associated with the Forskolin treatment (receptor agonist), which was expected. The Forskolin treatment was statistically different from Forskolin+Flutamide (FL blocks androgen receptors), which suggests that 3/?HSD is regulated by androgen receptors and not mineralocorticoid receptors (such as the ones in DOC). The results also demonstrate that passage number affects steroidogenic properties of H295R cells.
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ANTIMICROBIAL ACTIVITY IN THE COMPOSITE AND MINT FAMILIESThe design of this project is such that extracts from identified plants can be tested for antimicrobial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Experimental plants were collected along roadsides, in fields and in wooded areas in the following counties of Georgia: Burke, Columbia, Richmond, and Thomas. Plant material from the root, stem, leaf and flower were extracted in methylene chloride (Fischer, Fair Lawn, NJ). The plants were tested for antimicrobial activity using the agar diffusion assay method. Antimicrobial activities of these plant parts were compared to solvent control bactericidal data, and then the most active plants were further tested in hopes of determining quantitatively the amounts of antimicrobial activity, as well as the minimal inhibitory concentrations and the minimal bacterial concentrations. After extensive testing, it was concluded that methylene chloride should not be used in extracting plant materials, due to its high evaporative rate, resulting in toxicity of bacteria, yielding false positive results.