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  Partner: UNT Libraries
 Degree Discipline: Biology
 Collection: UNT Theses and Dissertations
Induction of 16α Hydroxylase in Human Cultured Lymphocytes

Induction of 16α Hydroxylase in Human Cultured Lymphocytes

Date: December 1975
Creator: Muijsson, Ingrid E.
Description: A method is presented for 160hydroxylase (SAH) induction in cultured human lymphocytes. SAH, a microsomal-associated enzyme, effects the oxidative conversion of 17pestradiol to estriol, which competes for cytoplasmic binding sites. 17,-estradiol and estrone are known mammary carcinogens, while estriol and its epimers have been suggested to have anticarcinogenic properties. To substantiate genetic variations of hydroxylase activity, an analysis of estrogen-induced cultured human lymphocytes was conducted to evaluate the frequency distribution of low, intermediate, and high SAH activity. Frequency analysis indicated that the control population distribution of SAH activity does not corroborate a proposed trimodal expansion of human SAH activity. A log normal distribution of SAH activity does exist, which suggests a polygenic mode of genetic control. SAH activity in a population of breast cancer patients and relatives of breast cancer patients showed no statistical difference from the SAH activity in the control population.
Contributing Partner: UNT Libraries
Permeability of the Kidney Capillaries to Narrow-Range Macromolecular Dextran Fractions

Permeability of the Kidney Capillaries to Narrow-Range Macromolecular Dextran Fractions

Date: August 1979
Creator: Wooldridge, Clayton Bradley
Description: Recent investigations into the permeability of the kidney capillaries have produced conflicting reports. This study was an attempt to better describe the permeability of the kidney capillaries by using narrow-range macromolecular dextran fractions in four molecular sizes: MW 61,400, MW 77,000, MW 118,000, and MW 147,000. Permeability was measured by dextran concentration differences in plasma and kidney lymph. Permeability decreased as the dextran molecular weight increased. Molecular weights 61,400 and 77,000 penetrated into the kidney lymph. Molecular weight 118,000 exhibited greater difficulty in penetrating to the lymph. The largest fraction penetrated into the kidney lymph with greatest difficulty. Plasma expansion by saline infusion increased the permeability of all dextran fractions.
Contributing Partner: UNT Libraries
The Effects of 3-Deazaguanine on Chick Embryo Fibroblasts and Rat Kidney Cells Infected with Temperature-Sensitive Mutant and Wild-Type Rous Sarcoma Viruses

The Effects of 3-Deazaguanine on Chick Embryo Fibroblasts and Rat Kidney Cells Infected with Temperature-Sensitive Mutant and Wild-Type Rous Sarcoma Viruses

Date: December 1979
Creator: Fadare, Samuel O.
Description: Chick embryo fibroblasts and rat kidney cells infected in vitro with Rous Sarcoma viruses were treated with 3-deazaguanine (3-DG). The findings revealed that 3-DG inhibited virus-induced cellular transformation. Degree of inhibition is dependent on concentration and frequency of media change. 3-DG at the concentrations tested will not reverse transformed cells to the untransformed state and does not have marked effect on replication of viruses. Upon removal of 3-DG, its effect was shown to be reversible. Cell growth was generally retarded in medium containing 3-DG. When xanthosine and inosine were added to the medium, cell growth was unaffected, but it increased in guanosine.
Contributing Partner: UNT Libraries
Genic Differentiation Between Two Chromosomal Races of Pocket Gophers, Geomys bursarius

Genic Differentiation Between Two Chromosomal Races of Pocket Gophers, Geomys bursarius

Date: May 1980
Creator: Bohlin, Raymond G.
Description: Genic data from two chromosomal races of Geomys bursarius from a contact zone in central Texas indicated that the two races possessed distinct gene pools which would define them as separate species. Data from proteins encoded from 21 loci in this study substantiated this hypothesis. A pattern of alternately fixed alleles at the ADH-l, MDH-2, LDH-l, and IDH-1 loci with no apparent gene flow in zones of contact strongly suggested that these two races should be designated as separate species. Levels of heterozygosity and high FST values indicate that genomic structuring within Geomys is most heavily influenced by high levels of inbreeding and low migration rates. Fossorial rodents were suggested to undergo speciation primarily through parapatric means.
Contributing Partner: UNT Libraries
Opthalmic Use Of Sodium Cephalothin: An In Vivo Comparison

Opthalmic Use Of Sodium Cephalothin: An In Vivo Comparison

Date: August 1979
Creator: Carney, Gerald R.
Description: A rabbit keratoconjunctivities model was used to evaluate ophthalmic formulations containing 1 percent sodium cephalothin in silicon oil, a 1 percent sodium cephalothin aqueous solution, and a 0.3 percent gentamicin sulfate solution. Rabit eyes were inoculated intracorneally with Pseudomonas aeruginosa, Staphylococcus aureus, or Streptococcus pneumoniae, After topical treatment, none of the antibiotic formulations were effective in the P. aeruginosa model; all three showed good activity against S. aureus, and against S. pneumoniae, the caphalothin formulations were more effective than gentamicin.In a related stability study, the cephalothin potency of the silicon formulation was maintained for 16 weeks at 4, 25, and 450 C These studies suggest that sodium cephalothin can be formulated as an effective and stable ophthalmic dosage form.
Contributing Partner: UNT Libraries
Effect of Operant Behavior on the Metabolism of 5-Hydroxytryptamine

Effect of Operant Behavior on the Metabolism of 5-Hydroxytryptamine

Date: August 1979
Creator: Shepard, Paul
Description: The role of operant behavior in the metabolism of brain 5-hydroxytryptamine (5-HT) turnover was investigated. Two and one-half hours following the administration of 150 mg/kg of para-chlorophenylalanine (PCPA), a specific inhibitor of tryptophan hydroxylase, levels of 5-HT were compared in sedentary and performing rats. Whole brain levels of serotonin were reduced in both responding and sedentary animals; however, differences between these groups were not statistically significant. The drug induced decrease in 5-HT levels was accompanied by a significant decrease in session responding. The degree of suppressed responding could be correlated with the level of 5-HT following PCPA, suggesting that the metabolism of serotonin is in part modulated by the rate of responding as maintained by the operant schedule.
Contributing Partner: UNT Libraries
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.
Contributing Partner: UNT Libraries
Histochemical Characterization of Lymphocytes in Preleukemic and Leukemic AKR Mice

Histochemical Characterization of Lymphocytes in Preleukemic and Leukemic AKR Mice

Date: May 1979
Creator: Michnoff, Carolyn A.
Description: The AKR strain of mice have a genetic trait for spontaneous development of lymphocytic leukemia. In this study, leukemic mice were found to have significantly larger (p<0.01) thymuses and spleens than preleukemic mice. The enlarged leukemic tissues were densely packed with a light staining cell, with a hollow-appearing nucleus. Tissues from preleukemic mice were observed to be infiltrated with a smaller, darker-staining lymphocyte. Fluorescent antibody staining was done on preleukemic and leukemic tissues, using three antisera against murine lymphocyte theta antigen, and an antiserum against murine IgG. Significantly brighter fluorescence, (p <0.05) with theta-specific antisera, was found in leukemic thymuses,spleens, and kidneys than in the same preleukemic tissues. Leukemic tissues had significantly brighter fluorescence (p <0.05) than preleukemic tissues with IgG antiserum.
Contributing Partner: UNT Libraries
Distribution, Abundance, and Food Habits of Larval Fish in a Cooling Reservoir

Distribution, Abundance, and Food Habits of Larval Fish in a Cooling Reservoir

Date: December 1978
Creator: Mitterer, Lana Gayle
Description: Analysis of larval fish collected at four stations in a 330-ha cooling reservoir indicated Dorosoma spp. were most numerous at all stations, followed by Lepomis spp. and Percina Macrolepida. Largest numbers and greatest diversity of larval fish were found at the station least affected by thermal effluent; the mid-lake station provided the smallest numbers and least diversity. The two warmwater stations were intermediate, with similar numbers and diversity. Diversity and abundance of zooplankton between stations were similar to those of fish. The most abundant zooplankter (Bosmina) was generally selected against by Dorosoma, Lepomis and Micropterus spp. larvae except when the larvae were quite small ((10mm). Cyclopoid copepods were most often selected by all larvae.
Contributing Partner: UNT Libraries
The Evolutionary Genetics of Campostoma anomalum and Campostoma oligolepis

The Evolutionary Genetics of Campostoma anomalum and Campostoma oligolepis

Date: December 1978
Creator: Merritt, Ronald L.
Description: Electrophoretic variation in 12 proteins encoded by 16 loci was analyzed to compare the genetic relationships of 18 natural populations representing two species of stoneroller minnows, Campostoma anomalum and C. oligolepis. Ten of the loci were monomorphic and fixed for the same allele in all populations of both species. One locus, Mdh-2, was found to separate both species. Mean heterozygosity for both species was 0.072. Estimates of levels of inbreeding indicated this phenomenon is operating in C. anomalum to structure the populations genetically. Mean genic identity (I) between the two species was high, 0.887, indicating the taxa are closely related. Nevertheless, data accumulated point to the conclusion that the two species maintain electrophoretic variation in 12 proteins encoded by 16 loci was analyzed to compare the genetic relationships of 18 natural populations representing two species of stoneroller minnows, Campostoma anomalum and C. oligolepis. Ten of the loci were monomorphic and fixed for the same allele in all populations of both species. One locus, Mdh-2, was found to separate both species. Mean heterozygosity for both species was 0.072. Estimates of levels of inbreeding indicated this phenomenon is operating in C. anomalum to structure the populations genetically. Mean genic identity (I) between ...
Contributing Partner: UNT Libraries
Effect of Colchicine on Neuronal Excitabilty

Effect of Colchicine on Neuronal Excitabilty

Date: August 1978
Creator: Okafo, Ngozi
Description: The abundance of microtubules in receptive dendrites suggests they may function in sensory transduction. Responses of frog muscle spindle receptors and joint receptors is inhibited within 25 minutes by 50 mM colchicine, a microtubuledisrupting agent. The inhibition is reversible upon removal of colchicine, and the time course of recovery is comparable to that of inhibition. Frog olfactory responses are briefly inhibited by washing the olfactory mucosa with perfusion fluid. Colchicine accentuates the inhibition and substantially retards the rate of recovery in a dose-dependent fashion. Colchicine does not affect axonal conduction, nor the oxygen uptake of isolated crab or frog leg nerves. The inhibitory action of colchicine is therefore an effect on the electrical excitability of the receptive dendrites or soma, and not an effect on axonal conduction.
Contributing Partner: UNT Libraries
Production and Energy Metabolism in Three Benthic Insect Populations in a Small North Central Texas Pond

Production and Energy Metabolism in Three Benthic Insect Populations in a Small North Central Texas Pond

Date: May 1978
Creator: Benson, Daniel J.
Description: Annual energy budgets of dominant benthic macro-invertebrates were examined during November 1973 to October 1974 from the benthos of a small pond ecosystem in north-central Texas. Estimates of annual secondary production (Hynes and Coleman 1968) were Procladius s. (Diptera, Chironimidae), 2.4 g m^-2 y^-1 (13 kcal m^-2 y^-1 ); Tendipes decorus (Diptera, Chironomidae), 6.0 g m^-2 y^-1 (40 kcal m^-2 y^-1 ); Brachycercus sp. (Ephemeroptera, Caenidae), 1.9 g m^-2 y^-1 (11 kcal m^-2 y^-1). Energy metabolism was measured in the laboratory at six seasonally encountered temperatures (5, 10, 15, 20, 25, and 30 C) on an acclimatization basis, and then extrapolated to the field. Estimates of annual energy metabolism are Procladius sp., 5.0 kcal m^-2 y^-1 ; Tendipes decorus, 17.2 kcal m^-2 y^-1 ; Brachycercus sp. 40.0 kcal m^-2 y^-1.
Contributing Partner: UNT Libraries
Nymphs of the Stonefly (Plecoptera) Genus Taeniopteryx of North America

Nymphs of the Stonefly (Plecoptera) Genus Taeniopteryx of North America

Date: May 1978
Creator: Fullington, Kate Matthews
Description: Nymphs of the 9 Nearctic Taeniopteryx species were reared and studied, 1976-78. Two morphologically allied groupings, the Taeniopteryx burksi-maura, and T. litalonicera- starki complexes corresponded with adult complexes. A key separating 7 species, based primarily upon pigment patterns and abdominal setal arrangements, was constructed. Taeniopteryx lita and T. starki were indistinguishable; T. burksi was separated from T. maurawhen no developing femoral spur was present. This study was based upon 839 nymphs. Mouthparts were not species-diagnostic. Detailed habitus illustrations were made for 6 species. Egg SEM study revealed that 3 species were 1.2-1.4 mm diameter, with a highly sculptured chorion, generally resembling a Maclura fruit; micropyle were scattered. Taeniopteryx lita, lonicera, starki and ugola nymphs were described for the first time.
Contributing Partner: UNT Libraries
Trophic Structure and Energy Flow in a Texas Pond

Trophic Structure and Energy Flow in a Texas Pond

Date: August 1978
Creator: Childress, William M.
Description: Annual energy flow and mean annual biocontent of eighteen compartments were determined for a 0.94 ha north central Texas pond ecosystem. Annual primary production was 7,780 kcal m^-2 yr^-2, and community production-to-respiration ratio was 1.49. One-third of annual primary production accumulated on the substrate as silt and sedimentation. Community production, production-respiration ratio, and biocontents of all compartments except aquatic insects were large in summer, small in winter. Biocontents of four trophic levels in the pond were all of the same order of magnitude, approximately 50 kcal m^-2. Suspended and benthic organic material forprimary consumers and terrestrial insects for tertiary consumers were substantial allochthanous energy imports into the pond system.
Contributing Partner: UNT Libraries
Thermal Selection at an Enzyme Locus in Populations of the Red Shiner, Notropis lutrensis, Receiving Hypolimnion Effluents from a Reservoir

Thermal Selection at an Enzyme Locus in Populations of the Red Shiner, Notropis lutrensis, Receiving Hypolimnion Effluents from a Reservoir

Date: May 1978
Creator: Richmond, M. Carol
Description: Genetic variation was examined at 19 loci encoding enzymatic and general proteins Notropis lutrensis from the Brazos River in Texas. The thermal regime of the Brazos River below Possum Kingdom Reservoir is altered due to the release of water from the hypolimnion. Summer water temperatures fluctuate as much as 7^oC. Levels of heterozygosity at the malate dehydrogenase-2 locus were correlated with the degree of water temperature fluctuation at each locality. The isozymes from three homozygous patterns of supernatant malate dehydrogenase (Mdh-l, Mdh-2) exhibited different activities at different experimental temperatures.
Contributing Partner: UNT Libraries
The Dynamics of a Planktonic Microcrustacean Community in a Small North Central Texas Pond Ecosystem

The Dynamics of a Planktonic Microcrustacean Community in a Small North Central Texas Pond Ecosystem

Date: December 1976
Creator: Smith, George Arthur
Description: Seven species of planktonic microcrustacea were identified from the North Texas State University Golf Course Pond. Total adult microcrustacean community density, biomass and biocontent, and seasonal cycles of each species were compared with northern populations. Species diversity and evenness indices were highest in summer and lowest in spring. Variations in microcrustacean density showed a positive correlation with density of phytoplankton. Temperature had a direct effect on metabolic rates of two species of copepods. Metabolic rates of pond species were lower at common temperatures than those of northern populations. An estimate of annual energy flow through the pond ecosystem showed cladocerans contributed the greater percentage of total energy to the next trophic level.
Contributing Partner: UNT Libraries
Diphenyloxazole Metabolism by Aryl Hydrocarbon Hydroxylase

Diphenyloxazole Metabolism by Aryl Hydrocarbon Hydroxylase

Date: December 1976
Creator: Abreu, Mary E.
Description: 2,5-Diphenyloxazole (PPO) was tested as a potential alternate inducer for the aryl hydrocarbon hydroxylase (AHH) system. Its apparent lack. of carcinogenicity and toxicity provide a possible system for investigation of enzyme systems related to chemical carcinogenesis without exposure of the researcher to potent carcinogenic compounds. These studies found PPO to be an inducer of AHH in cultured human lymphocytes. When PPO was utilized as a substrate for the AHH assay system, the major metabolites produced were strongly fluorescent. A simple fluorometric assay was developed which employed PPO as the substrate and which measured constitutive activity more efficiently than similar assays using benzo(a)pyrene as the substrate. Quantitation of both basal and induced lymphocyte AHH metabolism of PPO may be applicable to human population studies and may provide a tool to determine possible genetic variables with respect to carcinogen metabolism related to cancer risk.
Contributing Partner: UNT Libraries
The Effect of Light on Carotenoid Synthesis in Corynebacterium 7E1C

The Effect of Light on Carotenoid Synthesis in Corynebacterium 7E1C

Date: May 1977
Creator: Endicott, George R.
Description: The effects of light, light "mimicking" chemicals, and protein synthesis inhibitors on the photo-induced carotenogenesis of Corynebacterium 7EIC were studied. Changes in the dosage of fluorescent light applied to dark grown cells showed a dose related carotenogenic response. Maintaining the same dosage but varying the wavelength of monochromatic light revealed that light with a wavelength of 280 to 450nm was responsible for photo-induction. It further showed a peak of photo-induction between the wavelengths of 370 and 430nm. The light "mimicking" chemicals antimycin A and p-Chloromercurybenzoate were shown to have no light "mimicking" effects. The transcriptional inhibitor of protein synthesis actinomycin D partially inhibited, and chloramphenicol a translational inhibitor, completely inhibited photo-induced carotenogenesis.
Contributing Partner: UNT Libraries
Effect of Amino Acids on Growth and Cartenogenesis in Corynebacterium Species Strain 7E1C

Effect of Amino Acids on Growth and Cartenogenesis in Corynebacterium Species Strain 7E1C

Date: May 1977
Creator: Coughran, Carolyn S.
Description: Studies were evaluated on the effects of known growth factors on the growth and carotenogenesis of Corynebacterium species strain 7ElC. The complex medium, Tryptic Soy Broth,was found to stimulate growth and production of more pigment in the light and in the dark than did a mineral salts-glucose medium. A complete amino acid mixture added to LSG enhanced carotenogenesis in the dark in Corynebacterium 7ElC, while B-vitamins retarded carotenogenesis. No absolute requirement for one or more amino acids was found,indicating a multiple amino acid requirement. The fewest amino acids found to stimulate carotenogenesis in the dark were a combination of those in the Serine and Histidine families which include serine, glycine, cysteine, and histidine.
Contributing Partner: UNT Libraries
Life History Allocation of Energy to Growth and Reproduction in Gizzard Shad, Dorosoma cepedianum, in North Central Texas

Life History Allocation of Energy to Growth and Reproduction in Gizzard Shad, Dorosoma cepedianum, in North Central Texas

Date: December 1976
Creator: Fagan, Joseph A.
Description: Life history allocation of energy to growth and reproduction was determined for female gizzard shad. Absolute caloric energy allocated to eggs increased with age. The relative amount of production energy directed to reproduction increased with age up to 5 years and then decreased. Seasonal variation in lipids was studied. Quantitative changes occurred in ovarian lipids during the reproductive cycle. Carcass lipids varied seasonally. Age of sexual maturity was 3 years. Delayed maturity is attributed to high allocation of energy to growth enabling shad to outgrow intense competition and predation in pre-reproductive ages; there is little competition and predation in reproductive shad. Growth rates and condition factors indicated constant availability of food seasonally.
Contributing Partner: UNT Libraries
DNA-DNA Hybridization of Methane Oxidizing Bacteria

DNA-DNA Hybridization of Methane Oxidizing Bacteria

Date: December 1976
Creator: Ackerson, Jill W.
Description: Bacteria classified in the family Methylomonadaceae must derive their carbon from one-carbon compounds. They are characterized by the possession of internal membranes of two types. Type I membranes are layered and fill the middle of the cells while type II membranes form concentric layers around the periphery of the cells. Also, there are two metabolic pathways by which the methylobacteria assimilate one-carbon compounds. Further evidence of this dichotomy was sought by DNA-DNA saturation hybridization of DNAs from both types of methylobacteria. Very low DNA-DNA homology was seen between types I and II or within the types. It was not possible, therefore, to correlate the degree of genetic relatedness with either the nature of the internal membranes or the pathway of carbon assimilation.
Contributing Partner: UNT Libraries
The Hypothermic Perfusion of the Isolated Thyroid Gland and Its Release of T₃ And T₄

The Hypothermic Perfusion of the Isolated Thyroid Gland and Its Release of T₃ And T₄

Date: December 1976
Creator: Haenke, Richard F.
Description: Investigations have shown that the hypothalamus and pituitary respond to decreases in body temperature by stimulating thyroid release of T_3 and T_4 . This study was designed to bypass the control of the hypothalamus and pituitary gland and investigate the direct effect of temperature on the thyroid gland. Hypothermia was by an in vivo isolated perfusion of the thyroid gland. Radio-immunoassay was used to measure T_3 and T_4 concentrations. Significant increases were observed in animals perfused between 36º and 25ºc. These results indicate that the thyroid gland is directly effected by decreased temperature and that it is capable of exerting control over body temperature independent of the hypothalamus and pituitary gland. Lower perfusion temperatures produced no significant increases.
Contributing Partner: UNT Libraries
Physiological Studies of the Bdellovibrio-Host Interaction

Physiological Studies of the Bdellovibrio-Host Interaction

Date: December 1976
Creator: Dunton, Philip J.
Description: The purpose of this study was to focus attention on the physiology of the bdellovibrio-host interaction and to determine the metabolic requirements for this reaction. Since bdellovibrio is an aerobic organism, direct measurements of respiration, turbidity, and viable cell counts are reliable indications of the metabolic activity of the cells. It was determined that the metabolic requirements for the parasitic interaction are constituents from either metabolically active host cells or cells which are capable of at least some metabolic activity. The nutritional requirements of host-independent bdellovibrios suspended in buffer are not met by the presence or absence of viable or nonviable Enterobacter aegnes. Unlike the HD bdellovibrios, the HI bdellovibrios lack the ability to make economical use of their self-digesting processes.
Contributing Partner: UNT Libraries
Drumming Behavior of Selected Nearctic Stoneflies (Plecoptera)

Drumming Behavior of Selected Nearctic Stoneflies (Plecoptera)

Date: August 1976
Creator: Zeigler, David D.
Description: Drumming was recorded for 11 of 13 Nearctic stonefly species, representing 4 families. Both male and female signals were obtained from 5 species, and were either 2-way or 3-way communications. Signals were species-specific; those of males and females varied from 3-39 and 1-14 beats/ signal, respectively. Duration of male signals varied from 105-8,016 ms; those of females, except Perlinella drymo (1 beat), varied from 402-1318 ms. Signals among related taxa showed greatest similarities. Duration of male signals of Perlinella drymo became progressively shorter at each of 4 temperatures from 7-29 0C. Females of Perlinella drymo would only repeatedly answer male signals recorded at near their own temperature, and would not repeatedly answer recorded male signals of 8 other species.
Contributing Partner: UNT Libraries