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  Partner: UNT Libraries
 Department: Department of Biological Sciences
 Degree Level: Master's
 Collection: UNT Theses and Dissertations
DNA Typing of HLA-B by PCR with Primer Mixes Utilizing Sequence-Specific Primers

DNA Typing of HLA-B by PCR with Primer Mixes Utilizing Sequence-Specific Primers

Date: August 1997
Creator: Chiu, Angela Chen-Yen
Description: The aim of this study was to design a resolution typing system for the HLA-B gene. This technique involves a one-step PCR reaction utilizing genomic DNA and sequence-specific primers to determine the specificity of each allele and to produce a larger primer data base ideal for serological analysis. The application of this technique to serological analysis can improve serology detection which is currently hindered by antibody cross-reactivity and the unavailability of useful typing reagents.
Contributing Partner: UNT Libraries
Nicotinic Acetylcholine Receptor α3 mRNA in Rat Visual System After Monocular Deprivation

Nicotinic Acetylcholine Receptor α3 mRNA in Rat Visual System After Monocular Deprivation

Date: August 1997
Creator: Taylor, James H. (James Harvey), 1970-
Description: In situ hybridization was used to examine effects of monocular enucleation on nicotinic acetylcholine receptor subunit cc3 mRNA in the rat dLGNand visual cortex. After 28 days postoperative, there were no significant differences in α3 mRNA density between the contralateral (deprived) and ipsilateral (non-deprived) sides. The lack of obvious effects of visual deprivation on α3 mRNA density suggests that other factors, possibly intrinsic to dLGNand visual cortex, govern the postnatal expression of α3 mRNA.
Contributing Partner: UNT Libraries
Regulation of Escherichia coli pyrBI Gene Expression in Pseudomonas fluorescens

Regulation of Escherichia coli pyrBI Gene Expression in Pseudomonas fluorescens

Date: May 1995
Creator: Shen, Weiping
Description: Pseudomonas fluorescens does not appear to regulate the enzymes of de novo pyrimidine biosynthesis at the level of gene expression. Little or no apparent repression of pyr gene expression is observed upon addition of exogenous pyrimidines to the growth medium. The Escherichia coli pyrBI genes for aspartate transcarbamoylase (ATCase) were sized down and cloned into the broad host range plasmid, pKT230. Upon introduction into a P.fluorescenspyrB mutant strain, ATCase showed repression in response to exogenously fed pyrimidine compounds. Thus, it was possible to bring about changes in pyrimidine nucleotide pool levels and in transcriptional regulation of gene expression at the same time.
Contributing Partner: UNT Libraries
Neuronal Network Analyses in vitro of Acute Individual and Combined Responses to Fluoxetine and Ethanol

Neuronal Network Analyses in vitro of Acute Individual and Combined Responses to Fluoxetine and Ethanol

Date: August 2002
Creator: Xia,Yun
Description: Embryonic murine neuronal networks cultured on microelectrode arrays were used to quantify acute electrophysiological effects of fluoxetine and ethanol. Spontaneously active frontal cortex cultures showed highly repeatable, dose-dependent sensitivities to both compounds. Cultures began to respond to fluoxetine at 3 µM and were shut off at 10-16 µM. EC50s mean ± S.D. for spike and burst rates were 4.1 ± 1.5 µM and 4.5 ± 1.1 µM (n=14). The fluoxetine inhibition was reversible and without effect on action potential wave shapes. Ethanol showed initial inhibition at 20 mM, with spike and burst rate EC50s at 52.0 ± 17.4 mM and 56.0 ± 17.0 mM (n=15). Ethanol concentrations above 100 -140 mM led to cessation of activity. Although ethanol did not change the shape and amplitude of action potentials, unit specific effects were found. The combined application of ethanol and fluoxetine was additive. Ethanol did not potentiate the effect of fluoxetine.
Contributing Partner: UNT Libraries
Hepatotoxicity of Mercury to Fish

Hepatotoxicity of Mercury to Fish

Date: August 2010
Creator: Barst, Benjamin Daniel
Description: Tissue samples from spotted gar (Lepisosteus oculatus) and largemouth bass (Micropterus salmoides) were collected from Caddo Lake. Gar and bass livers were subjected to histological investigation and color analysis. Liver color (as abs at 400 nm) was significantly correlated with total mercury in the liver (r2 = 0.57, p = 0.02) and muscle (r2 = 0.58, p = 0.01) of gar. Evidence of liver damage as lipofuscin and discoloration was found in both species but only correlated with liver mercury concentration in spotted gar. Inorganic mercury was the predominant form in gar livers. In order to determine the role of mercury speciation in fish liver damage, a laboratory feeding study was employed. Zebrafish (Danio rerio) were fed either a control (0.12 ± 0.002 µg Hg.g-1 dry wt), inorganic mercury (5.03 ± 0.309 µg Hg.g-1 dry wt), or methylmercury (4.11 ± 0.146 µg Hg.g-1 dry wt) diet. After 78 days of feeding, total mercury was highest in the carcass of zebrafish fed methylmercury (12.49 ± 0.369 µg Hg.g-1 dry wt), intermediate in those fed inorganic mercury (1.09 ± 0.117 µg Hg.g-1 dry wt), and lowest in fish fed the control diet (0.48 ± 0.038 µg Hg.g-1 dry wt). Total mercury was ...
Contributing Partner: UNT Libraries
Functional Neural Toxicity and Endocrine Responses in Mice Following Naphthalene Exposure

Functional Neural Toxicity and Endocrine Responses in Mice Following Naphthalene Exposure

Date: August 2010
Creator: Colbert, Crystal
Description: Polycyclic aromatic hydrocarbons (PAHs) are a well studied and diverse class of environmental toxicants. PAHs act via the aryl hydrocarbon receptor (AhR), and studies have suggested that PAHs may elicit neurological and estrogenic effects. Doses of PAHs between 50 to 150 ppm may elicit neurotoxicity in rodent models. The present study investigated the effects of naphthalene on in vivo steroidogenesis in Swiss Webster male mice, and in vitro neural function of Balb-C/ICR mice frontal cortex neurons. These data suggest that naphthalene may not elicit steroidogenic effects at concentrations ranging from 0.2 to 25 mg/kg/day, following a 7 day subcutaneous dosing regime. In addition, naphthalene may cause functional toxicity of frontal cortex neurons at concentrations of 32 to 160 ppm naphthalene.
Contributing Partner: UNT Libraries
Effects of Sublethal Copper Exposure on Escape Behavior and Growth of  Rana pipiens Tadpoles

Effects of Sublethal Copper Exposure on Escape Behavior and Growth of Rana pipiens Tadpoles

Date: May 2002
Creator: Redick, Melinda
Description: This research is designed to test how sublethal exposure to copper affects tadpole predator-escape behavior and how quickly tadpoles recover. After exposure, tadpoles were separated. Escape behavior was recorded for two-thirds of exposed tadpoles while one-third of the exposed population was measured weekly to determine growth and recovery. Control tadpoles were consumed within 15 minutes whereas those exposed to higher concentrations were consumed at a slower rate, which does not support the hypotheses. Although the rate of predation was lower, tadpoles exposed to higher Cu concentrations were on average, 1.47 cm in total body length. Those exposed to 0.93 mg/L averaged 0.86 cm. After being placed into clean water, treatment tadpoles recovered after 20 days.
Contributing Partner: UNT Libraries
Individual, Social, and Seasonal Behavior of the Thirteen-Lined Ground Squirrel (Spermophilus tridecemlineatus)

Individual, Social, and Seasonal Behavior of the Thirteen-Lined Ground Squirrel (Spermophilus tridecemlineatus)

Date: January 1970
Creator: Wistrand, Harry E.
Description: The purpose of this study is to provide a qualitative, detailed description of individual and social behavior in a free-living population of thirteen-lined ground squirrels. Behavioral differences in relation to various periods of the annual cycle are also evaluated.
Contributing Partner: UNT Libraries
Influence of Acclimation and Acclimatization to Seasonal Temperatures on Metabolism and Energetics in the Rusty Lizard Sceloporus Olivaceus

Influence of Acclimation and Acclimatization to Seasonal Temperatures on Metabolism and Energetics in the Rusty Lizard Sceloporus Olivaceus

Date: May 1973
Creator: Dutton, Ronald Hugh
Description: Rates and energy equivalents of consumption (C), egestion+ excretion (FU) , assimilation (A), respiration (R) and production (P) were measured in two groups of Sceloporus olivaceus: 1) a laboratory group acclimated at four seasonally encountered temperatures (15, 20, 25 and 30°C) ; and 2) four acclimatization groups collected at different seasons when ambient temperatures corresponded to 15, 20, 25 and 30°C.
Contributing Partner: UNT Libraries
Experimental Trichinosis in Birds

Experimental Trichinosis in Birds

Date: December 1970
Creator: Poon, Yau-Lun
Description: This work concerns itself with essentially four experiments: (1) the cecum-injective-infection experiment; (2) the anus-injective-infection experiment; (3) the mouth ingestive-infection with larvae, and (4) the mouth ingestive-infection with the flesh of infected rats.
Contributing Partner: UNT Libraries
Mixed Culture of Chlorella Pyrenoidosa TX71105 and a Variant Strain of Bacillus Megaterium

Mixed Culture of Chlorella Pyrenoidosa TX71105 and a Variant Strain of Bacillus Megaterium

Date: August 1970
Creator: Yao, Raymond Che-Fong
Description: Very little work has been done on bacteria capable of significantly inhibiting algal growth. This thesis reports the research on mixed cultures of a high-temperature strain of algae, Chlorella pyrenoidosa TX71105, and an organism isolated from the air and tentatively identified as a variant strain of Bacillus megaterium.
Contributing Partner: UNT Libraries
Some Acute Effects of X-Irradiation (LD100) on Plasma and Adrenal Tissue Histamine in Rats

Some Acute Effects of X-Irradiation (LD100) on Plasma and Adrenal Tissue Histamine in Rats

Date: May 1972
Creator: Ferguson, James L.
Description: The effects of a lethal dose (1380 r) of X-irradiation on plasma and adrenal tissue histamine levels of rats were studied. The plasma histamine response was triphasic (increase at 1-3 hours, decrease at 5 and 9 hours and return to control at 24 hours post-irradiation). The adrenal tissue histamine response was found to be biphasic (decrease at 1 to 9 hours and a return to control level at 24 hours post-irradiation).
Contributing Partner: UNT Libraries
Obligately Thermophilic Nitrogen-Fixation in Some Soil Bacteria

Obligately Thermophilic Nitrogen-Fixation in Some Soil Bacteria

Date: August 1971
Creator: Milam, Mary
Description: In the work presented here, it is claimed that bacteria have been isolated which are capable of growth at high temperatures utilizing molecular nitrogen as their sole nitrogen source. Soil bacteria were isolated which grew at 55 C in nitrogen-free media. They were found to be obligatory thermophiles in nitrogen-free media and facultative thermophiles in media containing organically bound nitrogen.
Contributing Partner: UNT Libraries
The Larval Lipids of the Chironomid Midge Glyptotendipes Barbipes (Staeger)

The Larval Lipids of the Chironomid Midge Glyptotendipes Barbipes (Staeger)

Date: December 1971
Creator: Talent, John M.
Description: This problem was concerned with determining the total lipid content and individual lipid composition of the larvae of a local chironomid, Glyptotendipes barbipes (Staeger).
Contributing Partner: UNT Libraries
Some Effects of Electrostatic Fields on Brain Activity in Rats

Some Effects of Electrostatic Fields on Brain Activity in Rats

Date: December 1971
Creator: McCain, Harry B.
Description: This study concerned the effects of short-term exposures to continuous (10 kv/meter) and pulsed 20 volts at 640 cps/100 msecs) electrostatic fields on the EEG recorded from external electrodes and hypothalamic activity recorded from implanted electrodes in rats. Each experiment lasted at least 90 minutes. The total energies of the waveforms recorded were integrated and printed out for plotting and analysis. Besides the brain activity, the ECG, respiration, and temperature of the animals were also monitored before, during,and after exposure to the electrostatic fields.
Contributing Partner: UNT Libraries
Nucleotide Sequence of a Bovine Arginine Transfer RNA Gene

Nucleotide Sequence of a Bovine Arginine Transfer RNA Gene

Date: May 1996
Creator: Eubanks, Aleida C. (Aleida Christine)
Description: A single plaque-pure lambda clone designated λBA84 that hybridized to a ˆ32P-labeled bovine arginine tRNA was isolated from a bovine genomic library harbored in a lambda bacteriophage vector. A 2.3-kilobase segment of this clone was found to contain an arginine transfer RNAccg gene by Southern blot hybridization analysis and dideoxyribonucleotide DNA sequencing. This gene contains the characteristic RNA polymerase III split promoter sequence found in all eukaryotic tRNAs and a potential RNA polymerase III termination site, consisting of four consecutive thymine residues, in the 3'-flanking region. Several possible cis-acting promoter elements were found within the 5'-flanking region of the sequenced gene. The function of these elements, if any, is unknown.
Contributing Partner: UNT Libraries
Subcellular Localization of N-acylphosphatidyl-ethanolamine Synthase in Cotyledons of Cotton Seedlings

Subcellular Localization of N-acylphosphatidyl-ethanolamine Synthase in Cotyledons of Cotton Seedlings

Date: December 1995
Creator: Sriparameswaran, Anuja
Description: N-acylation of phosphatidylethanolamine (PE) with free fatty acids catalyzed by N-acyl phosphatidylethanolamine (NAPE) synthase was reported in cotyledons of 24-h-old cotton seedlings. Here I report subcellular localization of this enzyme. Differential centrifugation, sucrose density gradient fractionation,aqueous two-phase partitioning and electron microscopy techniques were utilized to elucidate subcellular site(s) of NAPE synthase. Marker enzymes were used to locate organelles in subcellular fractions. Differential centrifugation indicated that NAPE synthase is present in more than one organelle and it is a membrane bound enzyme. Sucrose density gradient fractionations indicated that NAPE synthase is present in membranes derived from endoplasmic reticulum (ER),Golgi and possibly plasma membrane (PM) but not mitochondria, glyoxysomes or plastids. Aqueous two-phase partitioning experiments with cotton and spinach tissues supported these results but Goigi appeared to be the major site of NAPE synthesis. Electron microscopy of subcellular fractions was used to examine isolated fractions to provide visual confirmation of our biochemical results. Collectively, these results indicate that NAPE is synthesized in plant ER, Golgi and possibly PM.
Contributing Partner: UNT Libraries
Comparative Bioavailability of Dietary and Dissolved Cadmium to Freshwater Aquatic Snails

Comparative Bioavailability of Dietary and Dissolved Cadmium to Freshwater Aquatic Snails

Access: Use of this item is restricted to the UNT Community.
Date: December 2003
Creator: White, Jessica C.
Description: Heavy metal bioaccumulation in aquatic organisms may occur through direct or indirect uptake routes. Research indicates that the significance of uptake route varies with contaminant and organism exposed. The relative importance of different metal sources in aquatic systems was investigated by exposing freshwater snails to dietary or dissolved sources of cadmium. Snails were exposed to control, contaminated food only, contaminated water only, and contaminated food and water treatments. During the 15-day exposure, samples were taken to determine Cd concentration in snail soft tissue, snail shell, algal food, and overlying water. Analyses of snail soft tissue and shells indicate that exposure route significantly affects Cd concentrations in the tissues. In both cases, dissolved Cd is the primary contributor to metal body burden.
Contributing Partner: UNT Libraries
Pyrimidine Genes in  Pseudomonas Species

Pyrimidine Genes in Pseudomonas Species

Date: December 2003
Creator: Roush, Wendy A.
Description: This thesis is a comparative study of gene arrangements in Pseudomonas species, and is organized into three major sections. The first section compares gene arrangements for different pathways in Pseudomonas aeruginosa PAO1 to determine if the gene arrangements are similar to previous studies. It also serves as a reference for pyrimidine gene arrangements in P. aeruginosa. The second part compares the physical, and genetic maps of P. aeruginosa PAO1 with the genome sequence. The final section compares pyrimidine gene arrangements in three species of Pseudomonas. Pyrimidine biosynthesis and salvage genes will be aligned for P. aeruginosa PAO1, P. putida KT2440, and P. syringae DC3000. The whole study will gives insight into gene patterns in Pseudomonas, with a focus on pyrimidine genes.
Contributing Partner: UNT Libraries
Influence of copper on resistance of Lumbricus terrestris to bacterial challenge

Influence of copper on resistance of Lumbricus terrestris to bacterial challenge

Date: August 2000
Creator: Simmons, Carla Stull
Description: Earthworms, Lumbricus terrestris, were challenged orally and intracoelomically with two bacterial species, Aeromonas hydrophila and Pseudomonas aeruginosa, and mortality rates were observed. Neither were found to be particularly pathogenic at injected doses of up to 108 bacteria per earthworm. The influence of Cu++ (as CuSO4) on the earthworm's response to bacterial challenge was investigated by exposing earthworms to sublethal levels of Cu++ prior to bacterial challenge. Exposure at sublethal concentrations up to 3 m g/cm2 did not have a pronounced influence on host resistance to challenge as measured by earthworm mortality. Cu++ increased the earthworm's ability to agglutinate rabbit erythrocytes, indicating that Cu++ exposure caused coelomocyte death, autolysis and release of agglutinins into the coelom, possibly explaining resistance to bacterial challenge.
Contributing Partner: UNT Libraries
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.
Contributing Partner: UNT Libraries
Induced Bradycardia Effects on Angiogenesis, Growth and Development in Early Development in Chicken Embryos, Gallus Domesticus

Induced Bradycardia Effects on Angiogenesis, Growth and Development in Early Development in Chicken Embryos, Gallus Domesticus

Date: December 2010
Creator: Ruck, Sylvia A.
Description: Cardiac performance, angiogenesis and growth was investigated during early chicken development. Heart rate, and thus arterial pulse pressure and cardiac output, were altered with the bradycardic drug ZD7288. Heart rates at 72 h of development of control embryos and those dosed with chicken Ringer were not different at 171 bpm. Acute and chronic application of ZD7288 caused significant bradycardia. Chronic dosing of Ringer and ZD7288 changed neither eye diameter nor development rate. Chronic dosing of ZD7288 did not significantly alter CAM vessel density close to the embryo (2, 3 and 4 mm) but at farther distances (5 and 6 mm) chronic dosing with both Ringer and ZD7288 decreased vessel density by 13 - 16%. Chronic dosing with ZD7288 also reduced body mass by 20%. Thus, lowered heart rate and cardiac output had little effect on vessel density or developmental stage, but did reduce embryo growth.
Contributing Partner: UNT Libraries
Photoactivatable Quantum Dots in Super-Resolution Microscopy of Muscle

Photoactivatable Quantum Dots in Super-Resolution Microscopy of Muscle

Date: December 2010
Creator: Akel, Amal
Description: Super-resolution 3D imaging was achieved using newly synthesized photoactivatable quantum dot (PAQ dot) probes. Quantum dots were modified with a novel quencher system to make them photoactivatable. The unique properties of these PAQ dots enable single-fluorophore localization in three dimensions using a confocal microscopy optical sectioning method. Myosin and tropomyosin of rabbit myofibrilar bundles were specifically labeled with the newly synthesized PAQ dot. A sufficient number of single quantum dots were photoactivated, localized and reduced to their centroid and then reconstructed to a super-resolution image. The acquired super-resolution image shows a lateral and an axial sub-diffraction resolution and demonstrates ultrafine striations with widths less than 70 nm that are not evident by conventional confocal microscopy. The striations appear to be related to nebulin thin filament binding protein. This newly developed imaging system is cutting edge for its high resolution and localization as well its simplicity and convenience.
Contributing Partner: UNT Libraries
The impact of invertebrates to four aquatic macrophytes: Potamogeton nodosus, P. illinoensis, Vallisneria americana  and Nymphaea mexicana.

The impact of invertebrates to four aquatic macrophytes: Potamogeton nodosus, P. illinoensis, Vallisneria americana and Nymphaea mexicana.

Date: August 2008
Creator: Nachtrieb, Julie Graham
Description: This research investigated the impact of invertebrates to four species of native aquatic macrophytes: V. americana, P. nodosus, P. illinoensis, and N. mexicana. Two treatments were utilized on each plant species, an insecticide treatment to remove most invertebrates and a non-treated control. Ten herbivore taxa were collected during the duration of the study including; Synclita, Paraponyx, Donacia, Rhopalosiphum, and Hydrellia. Macrophyte biomass differences between treatments were not measured for V. americana or N. mexicana. The biomasses of P. nodosus and P. illinoensis in non-treated areas were reduced by 40% and 63% respectively. This indicated that herbivory, once thought to be insignificant to aquatic macrophytes, can cause substantial reductions in biomass.
Contributing Partner: UNT Libraries
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