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 Degree Discipline: Biology
Effects of Peripheral Nerve Injury on the Cells of the Dorsal Root Ganglion: a Role for Primary Cilia

Effects of Peripheral Nerve Injury on the Cells of the Dorsal Root Ganglion: a Role for Primary Cilia

Date: December 2012
Creator: Smith, Sarah K.
Description: Primary cilia are ubiquitous sensory organelles found on most cell types including cells of the dorsal root ganglia (DRG). The DRG are groups of peripheral neurons that relay sensory information from the periphery to the CNS. Other cell types in the DRG include a type of glial cell, the satellite glial cells (SGCs). The SGCs surround the DRG neurons and, with the neurons, form functional sensory units. Currently are no reports describing the numbers of DRG cells that have cilia. We found that 26% of the SGCs had primary cilia. The incidence of cilia on neurons varied with neuron size, a property that roughly correlates with physiological characteristics. We found that 29% of the small, 16% of the medium and 5% of the large neurons had primary cilia. Primary cilia have been shown to have a role in cell proliferation in a variety of cell types. In some of the cells the cilia mediate the proliferative effects of Sonic hedgehog (Shh). In the CNS, Shh signaling through primary cilia affects proliferation during development as well as following injury, but no studies have looked at this function in the PNS. The SGCs and neurons of the DRG undergo complex changes following ...
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Effects of pH and Substrate on Growth of Escherichia Coli and Pseudomonas Aeruginosa in Mixed Continuous Culture

Effects of pH and Substrate on Growth of Escherichia Coli and Pseudomonas Aeruginosa in Mixed Continuous Culture

Date: January 1964
Creator: Cooper, Billy Howard
Description: The express purpose for doing this project was to develop methods for the continuous culture of E. coli and P. aeruginosa as a mixed population, and to apply these methods in studying the effects of pH and substrate upon the growth of these two organisms in mixed continuous culture.
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Effects of Ribavirin on Normal Rat Kidney Cells and Chicken Embryo Fibroblasts Infected with Rous Sarcoma Virus

Effects of Ribavirin on Normal Rat Kidney Cells and Chicken Embryo Fibroblasts Infected with Rous Sarcoma Virus

Date: April 1979
Creator: Jenkins, Frank J.
Description: Ribavirin, a synthetic nucleoside, was found to inhibit the replication of Rous sarcoma viruses (RSV) and subsequent cell transformation in chick embryo fibroblasts (CEF). It also blocked the transformation of normal rat kidney (NRK) cells infected with temperature-sensitive mutants of RSV. The action of Ribavirin was found to be reversible as removal of the drug from the NRK cells reversed the effects on cell transformation. Ribavirin appears to have a static effect on cell growth of both NRK and CEF cells. In addition, guanosine, xanthosine and inosine altered the effect of Ribavirin on cell growth.
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The Effects of Selected Algicides and Some Coordination Complexes upon the Apparent Photosynthesis of Chlorella Pyrenoidosa

The Effects of Selected Algicides and Some Coordination Complexes upon the Apparent Photosynthesis of Chlorella Pyrenoidosa

Date: June 1965
Creator: Phelps, Robert G.
Description: Many experiments have been performed with the Warburg apparatus, or variations of this manometric technique, since Warburg's experiments (52, 53) where the effects of cyanides upon dark reactions and of urethanes upon light reactions of photosynthesis were demonstrated. The same basic techniques were utilized in this research in attempting to determine the effects of some coordination complexes upon the apparent photosynthetic rate of Chlorella pyrenoidosa. A second goal of the present paper was to investigate the potential of the Warburg apparatus as a tool for screening algicidal compounds.
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Effects of Selected Phytohormones on the Growth and Morphology of Escherichia Coli

Effects of Selected Phytohormones on the Growth and Morphology of Escherichia Coli

Date: January 1968
Creator: Little, Lynn Mallory
Description: The present investigation was undertaken as a preliminary study to learn the response of Escherichia coli cells grown under identical experimental conditions to various concentrations of indoleacetic acid, gibberellic acid, and kinetin alone, and in combination with one another.
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Effects of Sertraline Exposure on Fathead Minnow (Pimephales Promelas) Steroidogenesis

Effects of Sertraline Exposure on Fathead Minnow (Pimephales Promelas) Steroidogenesis

Date: December 2014
Creator: Carty, Dennis R
Description: Sertraline is a selective serotonin reuptake inhibitor (SSRI) that is widely used for the treatment of depression and anxiety. Due to the abundant therapeutic use of sertraline, low levels have been detected in municipal wastewater effluents suggesting that aquatic organisms may be exposed. The purpose of this study was to evaluate the steroidogenic effects of sertraline on larval (FHM) and adult female fathead minnows (FFHM), Pimephales promelas. Larval FHM were exposed to 0.1, 1, and 10 µg/L sertraline for 28 days and analyzed via RT-qPCR for differential expression of 11β-Hydroxysteroid dehydrogenase (11β-HSD), 20β-Hydroxysteroid dehydrogenase (20β-HSD), aromatase (CYP19), and nuclear thyroid receptor alpha (TRα). FFHM were exposed to 3 or 10 µg/L sertraline for 7 days with the brain and ovary excised at exposure termination. Juvenile FHM exposed to 0.1 μg/L sertraline had a significant upregulation of both 20β-HSD and TRα. FFHM exposed to 10 µg/L sertraline had a significant upregulation of 11β-HSD expression in brain tissue, while no steroidogenic changes were observed in the FFHM ovary. Similarly, in FFHM brain tissue, CYP19 and 20β-HSD expression levels were significantly higher in fish exposed to 10µg/L sertraline compared to control. The significance of these findings with respect to survival, growth and reproduction ...
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The Effects of Simulated Altitude on the Intestinal Flora of Guinea Pigs

The Effects of Simulated Altitude on the Intestinal Flora of Guinea Pigs

Date: May 1969
Creator: Funderburk, Noel R.
Description: The purpose of this paper is to report the results of studies on the aerobic, mesophilic intestinal flora of guinea pigs subjected to conditions similar to those encountered by man in spacecraft.
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The Effects of the Soil Conditioner, Superbio, Upon the Cellulose Decomposing Bacteria and the Crop Yield of a Soil

The Effects of the Soil Conditioner, Superbio, Upon the Cellulose Decomposing Bacteria and the Crop Yield of a Soil

Date: August 1968
Creator: Gunn, Bruce Alan
Description: The purpose of this investigation was to determine if a commercial soil conditioner, Superbio, can improve crop yield, and if the "advertised" soil improvement might be due to an increase in the activity and numbers of aerobic cellulose decomposing bacteria following treatment.
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Effects of Triclosan, Triclocarban, and Caffeine Exposure on the Development of Amphibian Larvae.

Effects of Triclosan, Triclocarban, and Caffeine Exposure on the Development of Amphibian Larvae.

Date: August 2009
Creator: Palenske, Nicole Marie
Description: Triclosan and triclocarban are antimicrobials found in numerous consumer products, while caffeine is the most commonly consumed stimulant by humans. This study was undertaken to determine the effects of triclosan, triclocarban, and caffeine on the development and physiology of amphibian larvae. LC50 values of triclosan and triclocarban were determined after 96 hours for three North American larval species: Acris crepitans blanchardii, Bufo woodhousii woodhousii, Rana sphenocephala, and for a common amphibian developmental model: Xenopus laevis. Amphibian larvae were most sensitive to triclosan and triclocarban exposure during early development based upon 96-hour LC50 values. Heart rates for X. laevis and North American larvae exposed to triclosan were variable throughout development. However, significantly lower heart rates were observed in all larvae exposed to triclocarban. Metabolic rates of X. laevis and R. sphenocephala larvae exposed to triclosan were significantly affected in larvae exposed to ½ LC50 and the LC50 concentration. Metabolic rates of X. laevis larvae exposed to triclocarban were significantly affected by exposure to ½ LC50 concentrations in three of four stages investigated. No significant differences were observed in North American larvae exposed to triclocarban. Tissue uptake, lipid uptake, tissue bioconcentration factor (BCF) and lipid BCF of triclosan and triclocarban were investigated ...
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Effects of Turbidity on Gilling Rates and Oxygen Consumption on Green Sunfish, Lepomis cyanellus

Effects of Turbidity on Gilling Rates and Oxygen Consumption on Green Sunfish, Lepomis cyanellus

Date: May 1974
Creator: Horkel, John Duane
Description: Laboratory studies conducted at 5, 15, 25, and 35 C measured changes in gilling rates and oxygen consumption of green sunfish in response to exposure to bentonite clay suspensions. The tests indicate that gilling rates are not affected by bentonite clay suspensions below 2125 FTU at 5 C, 1012 FTU at 15 C, and 898 FTU at 25 C. At turbidity levels exceeding 1012 FTU at 15 C and 898 at 25 C, gilling rates increased 50-70%. Tests were inconclusive at 35 C. Oxygen consumption rates were found to be unaffected by turbid suspensions below 3500 FTU at all four temperatures. Evidence suggests that increased gilling rates under highly turbid conditions are a means of compensating for reduced respiratory efficiency and a strategy for maintaining a constant oxygen uptake. Evidence indicates that the cost of increased gilling rates is probably met by a reduction in activity.
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Effects of Visible Monochromatic Radiations on Growth of Pith Callus Tissue of Pelargonium Zonale

Effects of Visible Monochromatic Radiations on Growth of Pith Callus Tissue of Pelargonium Zonale

Date: August 1966
Creator: Ward, H. Bailey
Description: It was the purpose of the investigation to determine the effects of selected high intensity monochromatic radiations on the growth of pith callus tissue of Pelargonium zonale, variety Enchantress Fiat. In addition, the extent of cell differentiation was to be determined for tissues grown under each experimental treatment.
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Effects of Whisker-Trimming on GABAA Receptors in S1 Cortex

Effects of Whisker-Trimming on GABAA Receptors in S1 Cortex

Date: August 2004
Creator: Salazar, Eduardo
Description: A number of studies have shown that sensory deprivation is associated with selective decreases in GABA, GAD, and GABA receptors, in deprived areas of visual and somatosensory cortex. Those studies focused on layer 4, a recipient of direct thalamocortical sensory input. However, supragranular layers 2/3 have been recently identified as a major locus of functional plasticity in sensory deprivation and long-term potentiation. To examine whether GABAA receptors in layers 2/3 are affected by sensory deprivation, rats had mystacial vibrissae in middle row C or rows ABDE trimmed for 6 weeks beginning in early adulthood. Layers 2/3 above the deprived and adjacent whisker barrels were located in tangential sections, using patterns of radial blood vessels as fiducial marks. In deprived whisker barrel columns, [3H]muscimol binding to GABAA receptors decreased by 12.8% ± 1.2 (P &lt; 0.001) in layers 2/3 and 11.4% ± 1.2 (P<0.001) in layer 4. Altered levels of GABAA α1 subunit (Fritschy et al., 1994) were indicated by reduced optical density of immunostaining, both in deprived layers 2/3 (6.4% ± 0.7; P&lt; 0.001) and in layer 4 (3.4% ± 1.0; P &lt; 0.005). Interestingly, Nissl staining density also decreased in deprived layers 2/3 (12.7% ± 1.8 P &lt; 0.001) ...
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Effects of X-Irradiation of Respiration in Frog Brain Tissue Slices Using the Oxygen Electrode Method

Effects of X-Irradiation of Respiration in Frog Brain Tissue Slices Using the Oxygen Electrode Method

Date: August 1971
Creator: Lin, Chen-hsiung
Description: The effects of X-irradiation at dosages of 40 r, 80 r, 160 r, 240 r, 320 r, 400 r, 800 r, 4 Kr, 8 Kr, and 16 Kr on the oxygen uptake of frog brain (Rana pipiens) tissue slices were studied. A membrane-covered oxygen electrode method was used to measure the respiratory rate. Continuous recordings were made before, during, and following X-irradiation in all of the test experiments. X-irradiation was delivered from a G. E. beryllium window X-ray unit at 120 KVP, 5 ma with a 1/4 mm Al filter.
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Effects of X-irradiation on Ion Flux in Desheathed Toad Sciatic Nerves

Effects of X-irradiation on Ion Flux in Desheathed Toad Sciatic Nerves

Date: January 1969
Creator: Albin, Leslie O.
Description: The purpose of this thesis is to determine the effects of x-irradiation on the efflux of potassium, sodium and calcium ions from stimulated and unstimulated desheathed sciatic nerves.
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Effects of X-Irradiation on Na22 Efflux in Isolated Nerves

Effects of X-Irradiation on Na22 Efflux in Isolated Nerves

Date: January 1964
Creator: Yang, Chui-hsu
Description: The purpose of this study was twofold: 1) to present experimental data on changes in permeability of fibers during irradiation using Na22 as the tracer isotope, and 2) to attempt to correlate these findings with the electrical changes observed.
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Effects of X-irradiation on Potassium Flux in Isolated Nerves

Effects of X-irradiation on Potassium Flux in Isolated Nerves

Date: August 1966
Creator: Ramsey, Christian Norman
Description: The purpose of this study, therefore, was threefold in nature: (1) to determine the effects of x-irradiation on the influx and efflux of potassium in compound nerve fibers (2) to attempt to relate the radiation-induced changes in electrical activity with potassium flux and (3) to use the information obtained to gain insight into the possible cellular site (s) of radiation insult to compound nerves.
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Effects of X-Irradiation on Water and Ion Flux in Isolated Roots

Effects of X-Irradiation on Water and Ion Flux in Isolated Roots

Date: January 1967
Creator: Wall, Malcolm J.
Description: Due to the relatively small amount of work concerning radiation, it was thought feasible to use ionizing radiation as a tool to study the relationship between water and salt flux in isolated root systems. Moreover, the more quantitative potometric method lends itself well to such a study, since the two processes can be followed simultaneously. the aims of this study, therefore, were 1) to determine effects of X-irradiation on water, calcium and potassium flux in excised onion roots; 2) to determine the dose levels required for producing permeability changes; 3) to investigate the nature of radiation damage to root systems; and 4) to attempt to shed light on the relation between water transport and ion movement in root systems.
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Electron Microscopy of Vesicles Present in Bacterial Lysates of Escherichia Coli

Electron Microscopy of Vesicles Present in Bacterial Lysates of Escherichia Coli

Date: August 1966
Creator: Shaw, James Elwood
Description: It is the purpose of this thesis to report further studies on the vesicles appearing in phage lysates of Escherichia coli, phage attachment to these vesicles, and the presence of similar vesicles in lysozyme and penicillin lysed cultures.
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Enallagma civile (Odonata: Coengrionidae) life history and production in a west Texas playa

Enallagma civile (Odonata: Coengrionidae) life history and production in a west Texas playa

Date: May 2002
Creator: Booker, Jennifer Suzanne
Description: A life history and productivity study of Enallagma civile was conducted in a playa that was located in the southern High Plains of Texas. Other odonates were also studies to identify their contributions to the habitat.
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Endocannabinoid System in a Planarian Model

Endocannabinoid System in a Planarian Model

Date: December 2010
Creator: Mustonen, Katie Lynn
Description: In this study, the presence and possible function of endocannabinoid ligands in the planarian is investigated. The endocannabinoids ananadamide (AEA) and 2-arachidonoylglycerol (2-AG) and entourage NAE compounds palmitoylethanolamide (PEA), stearoylethanolamide (SEA) and oleoylethanolamide (OEA) were found in Dugesia dorotocephala. Changes in SEA, PEA, and AEA levels were observed over the initial twelve hours of active regeneration. Exogenously applied AEA, 2-AG and their catabolic inhibition effected biphasic changes in locomotor velocity, analogous to those observed in murines. The genome of a close relative, Schmidtea mediterranea, courtesy of the University of Utah S. med genome database, was explored for cannabinoid receptors, none were found. A putative fatty acid amide hydrolase (FAAH) homolog was found in Schmidtea mediterranea.
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Endocrine Disruption of Levonorgestrel in Early-life Stages of Fathead Minnows, Pimephales Promelas

Endocrine Disruption of Levonorgestrel in Early-life Stages of Fathead Minnows, Pimephales Promelas

Date: August 2013
Creator: Overturf, Matthew D.
Description: Pharmaceuticals have routinely been detected in the environment resulting in a growing concern about whether these drugs could elicit effects on aquatic organisms. The concerns are centered on the highly conserved nature of mammalian therapeutic targets in fish. These pharmaceuticals are found at very low levels in the environment, which can result in sub-lethal effects in aquatic organisms. Therefore, 28 d early-life stage studies were conducted on six pharmaceuticals to assess their impacts on survival and growth fathead minnow larvae. Two pharmaceuticals tested, carbamazepine and fenofibrate, resulted in no alterations to survival and growth. However, amiodarone, clozapine, dexamethasone, and levonorgestrel (LNG) reduced survival at concentrations tested with LNG being the most potent at 462 ng/L. Survival was increased with amiodarone and clozapine; however LNG significantly decreased growth at 86 ng/L. Therefore, the most potent pharmaceutical tested was the synthetic progestin LNG with survival and growth impacts at concentrations less than 1 μg/L. Further analysis was conducted by measuring specific endocrine related mRNA transcript profiles in FHM larvae following the 28 d ELS exposure to LNG. Transcripts of 3β-HSD, 20β-HSD, and FSH were significantly down-regulated following 28 d exposure to both 16.3 and 86.9 ng/L LNG. Also, CYP19a expression was significantly ...
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Endogenous Levels of Indole-3-Acetic Acid in Synchronously Grown Chlorella Pyrenoidosa

Endogenous Levels of Indole-3-Acetic Acid in Synchronously Grown Chlorella Pyrenoidosa

Date: August 1971
Creator: Grotbeck, Laurence Merritt
Description: The purpose of this study was to determine the endogenous levels of indole-3-acetic acid throughout the life cycle of Chlorella pyrenoidosa, and to show a correlation between onset of cell division and IAA levels.
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Environmental Modulation of the Onset of Air-breathing of the Siamese Fighting Fish and the Blue Gourami

Environmental Modulation of the Onset of Air-breathing of the Siamese Fighting Fish and the Blue Gourami

Access: Use of this item is restricted to the UNT Community.
Date: December 2015
Creator: Mendez Sanchez, Jose Fernando
Description: This study determined the effect of hypoxia on air-breathing onset and physiological and morphological characters in larvae of the air breathing fishes Trichopodus trichopterus and Betta splendens. Larvae were exposed intermittently (12/12 h daily) to 20, 17, and 14 kPa of PO2 from 1 to 40 days post-fertilization. Survival, onset of air breathing, wet body mass, O2, Pcrit were measured every 5 dpf. Hypoxia advanced by 4 days, and delayed by 9 days, the onset of air breathing in Betta and Trichopodus, respectively. Hypoxia increased larval body length, wet mass, and labyrinth organ respiratory surface of Betta, but did not affect these factors in Trichopodus. Hypoxic exposure increased O2 by 50-100% at each day throughout larval development in Betta, but had no effect on larval Trichopodus. Hypoxia decreased Pcrit in Betta by 37%, but increased Pcrit in Trichopodus by 70%. Larval Betta reared in hypoxia showed a modified heart rate:opercular rate ratio (3:1 to 2:1), but these changes did not occur in Trichopodus. Compared to Betta, the blood of Trichopodus had a higher P50 and much smaller Bohr and Root effects. These interspecific differences are likely due to ecophysiological differences: Betta is a non- obligatory air-breather after 36 dpf with ...
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Enzyme Assays Using Earthworms for Assessing Innate and Nonspecific Immunotoxicity of Xenobiotics

Enzyme Assays Using Earthworms for Assessing Innate and Nonspecific Immunotoxicity of Xenobiotics

Date: May 1992
Creator: Chen, Shing-Chong
Description: Principal objectives of my research were to: (1) report for the first time that coelomocytes are able to reduce NBT dye and confirm the presence of lysozyme-like activity in earthworm; (2) develop a standard methodology for determination of NBT reduction and lysozyme-like activity in earthworms; (3) compare NBT reduction and lysozyme-like activity in earthworms with those of murine and human cells and fluids; and (4) demonstrate the sensitivity of earthworm NBT reduction and lysozyme-like activity as the assays using matrics in refuse-derived fuel fly ash (RDFF) and CuSO4.
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