Biology Commons^™

Effect Of Insulin And Vanadate On Sre-Mediated C-Fos Expression And Jnk Activation, Francisco J. Berguido

Masters Theses

Insulin mimetics are compounds that mimic the action of insulin in the body and are currently being studied as possible therapeutic agents against diabetes. Vanadium has been identified as an element with insulin-like properties with regard to metabolic processes such as lowering blood glucose levels. Few studies have implicated vanadium in mitogenic actions such as cell growth and differentiation. We studied the action of vanadate on the expression of the insulin-induced SRE, a cis-element of the well-characterized mitogenic gene c-fos. We measured this expression by means of a plasmid containing the reporter gene luciferase linked to the sequences from c-fos …

The Brood-Rearing Habitat, Brood Home Range, And Fecundity Of The Snowy Plover (Charadrius Alexandrinus) In Coastal Southern Texas, Jeffery R. Rupert

Theses and Dissertations - UTB/UTPA

Habitat fragmentation has been shown to have negative effects on avian communities. I looked at the effects of corridor width and vegetation characteristics on nesting densities and breeding success of birds in the Lower Rio Grande Valley. There were definite trends in this study of increasing species richness and nesting densities with increasing corridor widths. Multiple regression revealed little correlation between tree density, diameter at breast height, tree height, canopy cover and ground cover with nesting density or nesting success. However, factors such as parasitism by the Bronzed Cowbird (Molothrus aeneus) and predation were much greater in narrower corridors. This …

Activation Of Signal Proteins By Insulin And Selenite In Primary Rat Hepatocytes, Ginny Lynn Garlock

Masters Theses

Insulin has a wide range of metabolic and mitogenic effects in cells. The mechanism of insulin action in controlling these events is not well understood, but involves, at least in part, a complex phosphorylation cascade. Selenate has been shown to mimic insulin on several metabolic processes, including the regulation of glucose-6-phosphate dehydrogenase (G6PDH) gene expression. Its mechanism of action, however, is not known. To investigate the mechanisms of insulin and selenate action on the regulation of G6PDH, signal proteins from primary rat hepatocytes were first studied. Insulin and sodium selenate similarly increased tyrosyl phosphorylation of the β-subunit of the insulin …

Isolation And Characterization Of Cadmium Hypertolerant Mutants Of Arabidopsis Thaliana, Santiago Xavier Navarro

Masters Theses

Cadmium is an environmental pollutant which accumulates by deposition from anthropogenic activities. Plants readily take-up cadmium from soil and is concentrated in shoot tissues. Plant and animal systems are affected detrimentally by the exposure to cadmium and are known to produce metal binding peptides as part of detoxification mechanisms. In an attempt to find alternative methods of soil cleanup, efforts are being undertaken to isolate heavy metal accumulating plants. Alternatively, to reduce the accumulation of cadmium in food, plants that exclude heavy metals are also being sought. The objective of this project was to isolate mutants which can be used …

Age Related Changes In The Activity And The Responsiveness Of The Renin-Angiotensin System In The 15 Month Old Rat, Michele Mckee Thompson

Dissertations and Theses

Progressive deterioration of renal function is one consequence of aging. Glomerular maladaptation is one aspect of this and includes increased glomerular capillary hypertension and a reduced ultrafiltration coefficient, which can lead to glomerular sclerosis and proteinuria. In the aging rat, angiotensin converting enzyme inhibitors (CEI) lower proteinuria (U_protV) and decrease glomerular sclerosis (2, 18, 24, 45). Accordingly, alterations in the circulating and renal renin-angiotensin system (RAS) are hypothesized to play a role in the pathogenesis of renal disease in the aging rat. Previous studies using rat models have demonstrated a lower responsiveness to converting enzyme inhibitor treatment in …

Whole Body I=In Vivo Vascular Compliance In Two Amphibians, Bufo Marinus And Rana Cate, Todd Micheal Hoagland

Dissertations and Theses

The mean circulatory filling pressure (MCFP), vascular compliance (C) and unstressed volume (USV) were measured in Bufo marinus and Rana catesbeiana, using an in vivo preparation. Capacitance curves were constructed by varying total vascular volume and then measuring MCFP. These capacitance curves enable the extrapolation of USV and the measurement of vascular compliance. The MCFP, C, and USV were 8.6 ± 0.2 (mmHg), 3.7 (ml· mmHg-1 · kg- 1 ) and 2.5 (ml), respectively, in B. marinus. The MCFP, C, and USV were 9.5 ± 0.1 (mmHg), 2.2 (ml· mmHg-1 · kg- 1 ) and 14.2 (ml), respectively, …

Human Trampling In The Upper Rocky Intertidal: Trampling And Recovery In Barnacle Mediated Succession, Timothy Lawrence Grubba

Dissertations and Theses

Marine intertidal ecosystems are vulnerable to human interference,

because trampling can be a significant problem. I studied the impacts of

trampling on community patterns and succession in a rocky intertidal

habitats. This study was divided into two phases: ( 1) a trampling phase and

(2) a recovery phase. Both phases are focused on two barnacles, Balanus

glandula and Chthamalus dalli, and on fucoid and red algae. The trampling

phase tested the effects of trampling on these organisms. The effects of

herbivores, primarily limpets (Collisella digitalis) were also tested to

determine whether anthropogenic (trampling) and natural (herbivory and

limpet bulldozing) disturbances …

Detection Of Hybridization Events Between The Coyote, Canis Latrans, And The Domestic Dog, Canis Familiaris, Using Two Polymorphic Microsatellite Loci And Cranial Morphometric Analysis, John Jobe Cox

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by John Jobe Cox on August 26, 1997.

Whole Body In Vitro Hydraulic Conductivity And Transcapillary Filtration In Two Amphibians, Bufo Marinus And Rana Catesbeiana, Thomas Vincent Hancock

Dissertations and Theses

The capillary filtration coefficient (CFC) and isovolumetric capillary pressure (P_ci) were measured in Bufo marinus and Rana catesbeiana, using a gravimetric technique on an in vitro preparation while perfusing with Ringers and 0.1 g·100 ml^-1 bovine serum albumin Estimates of pre- and post-capillary resistance were obtained from Bufo; the post- to pre-capillary resistance ratio was found to be 0.18, which was used to estimate capillary pressure. CFC was found to be 6.68 ± 0.51 and 5.07 ± 0.23 ml·min^-1·kg^-1·mmHg^-1 and P_ci was found to be 7.4 and 6.3 mmHg in …

A Profile Of Antibiotic Resistant Bacteria In The James River, Keith Allen Boisvert

Master's Theses

Spatial and temporal variability in the antibiotic resistance of bacterial assemblages in the lower portion of the James River was examined. The antibiotic resistance of culturable coliforms was compared to the resistance in the microbial community. Antibiotic resistance was determined via colony formation on media containing antibiotics. The antibiotics ampicillin, chloramphenicol, streptomycin and tetracycline were used at concentrations ranging from 10 to 500 ug/ml. Statistically significant differences in the mean number of antibiotic resistant isolates were observed among both sample sites and dates. The sampling site at river mile 99 just below Richmond showed both increased antibiotic resistance and bacterial …

Isolation And Characterization Of Luxi And Luxr Homologues From Edwardsiella Ictaluri, Edward Todd Jacobs

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Edward Todd Jacobs on August 1, 1997.

Oxyconformity In Burrow-Dwelling Crustaceans : Aerobic Metabolism Of Hemisquilla Ensigera Californiensis, Leandra P. Peters

Loma Linda University Electronic Theses, Dissertations & Projects

Hemisquilla ensigera califomiensis is an active burrow-dwelling stomatopod crustacean common off the coast of Southern California (Basch and Engle, 1989). In this experiment I measured the typical burrow oxygen level, time taken to deplete the oxygen in an inhabited, capped burrow, and tested the hypothesis that H. ensigera, like other burrow dwellers that have been examined, is an oxyregulator; and that like crustaceans in general, they have only limited anaerobic capabilities. Contrary to expectations, I found that H. ensigera is an oxyconformer or at best a weak oxyregulator, and that the species has substantial anaerobic capacity. Since it was …

Partial Characterization Of Na+, K+-Atpase And Its Gill And Antennal Gland Osmoregulatory Role In The Crayfish, Orconectes Putnami, Michael E. Fultz

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Michael E. Fultz on August 1, 1997.

The Role Of Free Radicals In The Plant's Response To Pathogen Attack In Tobacco, Phillip L. Peters

Masters Theses

Previous studies have implicated the involvement of free radicals, specifically reactive oxygen species (ROS), as a key component in plant response to pathogen attack. In this study we examined the effect free radical scavenging compounds have on lesion area, salicylic acid levels, catalase, and superoxide dismutase in response to inoculation with Tobacco Mosaic Virus (TMV), a viral pathogen. Hydroponically grown Nicotiana tabacum (Xanthi nc) were pretreated with one of two antioxidants, either purpurogallin (PPG) or N-acetyl cysteine (NAC). Antioxidants were supplied to the plant via the root system and the leaves were subsequently challenged by inoculation with theTMV. Leaf material …

The Effect Of Lymph Sac Pressure On Lymph Heart Pressure Development In The Toad Bufo Marinus, Michael Georgitsis

Dissertations and Theses

Lymph hearts play an important role in blood volume regulation in anurans by controlling the movement of fluid from the lymphatic spaces to the vasculature. The anatomical continuity between lymph sacs and lymph hearts predicts a coupling of pressure between the two structures which may represent a physical basis for lymph heart regulation. The precise relationship between lymph heart pressure and lymph heart output was not examined so that conclusions regarding changes in work performed by the hearts as a result of changing lymph sac pressure could not be made. However, increases in lymph sac pressure led to increases in …

A Pouplation Genetic Study Of Wild Bottlenose Dolphins (Tursiops Truncatus) In Matagorda Bay, Texas, Joel Stephen Lenox

Dissertations and Theses

A long-term photoidentification study was initiated in response to an unusually high incidence of bottlenose dolphin mortality between Corpus Christi and Matagorda Bays, Texas. Blood samples from 36 captured and released animals were analyzed using three genetic techniques; mtDNA haplotyping, nuclear DNA fingerprinting and electrophoretic analysis of hemoglobin. Two Hinf I mtDNA haplotypes previously described in bottlenose dolphins from other locations within the Gulf of Mexico were discovered. Similarity Indices (SI) were calculated based on nuclear DNA fingerprinting data. These SI values were used as a relative measure of relatedness between two individuals run on the same gel. Means of …

Ovarian Steroid Regulation Of Tryptophan Hydroxylase Enzyme Level In The Midbrain Raphe In Ovariectomized Guinea Pigs, Zhidong Lu

Dissertations and Theses

Progesterone stimulates prolactin secretion in estrogen ( estradiol-17-~)primed monkeys and guinea pigs. It is hypothesized that the serotonin neural system plays a pivotol role in mediating the effect of progesterone on prolactin secretion. Indeed, progesterone, but not estrogen, increases serotonin levels in the midbrain raphe in guinea pigs. However, estrogen alone stimulates gene expression of the rate-limiting enzyme for serotonin synthesis, tryptophan hydroxylase (TPH), and progesterone supplement to the estrogen regimen has no additive effect, as indicated by TPH mRNA levels in monkeys. The discrepancy between ovarian steroid effects on the TPH mRNA level and the serotonin level might be …

The Role Of The Hepatic Vagus In The Pathogenesis Of Fever, Christopher Todd Simons

Dissertations and Theses

Recent evidence has suggested a role of vagal afferents in the pathogenesis of fever. Although bilateral truncal subdiaphragmatic vagotomy has been shown to attenuate the febrile response to lipopolysaccharide (LPS) and interleukin-1, no study has yet been able to verify which of the five subdiaphragmatic vagal branches (viz., the anterior and posterior celiac branches, the anterior and posterior gastric branches, and the hepatic branch) is responsible for communicating this signal. The present study tested the hypothesis that the hepatic vagal branch mediates pyrogenic signals from the periphery to the brain. Male Wistar rats underwent one of four selective …

Structural And Successional Analysis Of Woodland Vegetation In Tualatin Hills Nature Park, Christopher J. Dobson

Dissertations and Theses

Tualatin Hills Nature Park is an urban woodland located in Beaverton, Oregon. The park is owned and managed by Tualatin Hills Park & Recreation District. Vegetation in the park is in a state of secondary succession following a long history of disturbance. The site provided an excellent opportunity to study the recovery of a natural woodland in an urban setting in the northern Willamette Valley.

The purpose of this study was to analyze the species composition, structure, and successional trends of the woodland vegetation in Tualatin Hills Nature Park. A secondary purpose was to determine if there were any natural …

Development Of Fetal Putative Blue Retinal Ganglion Cells Of Rhesus Macaque, Michael Snyder

Loma Linda University Electronic Theses, Dissertations & Projects

Steineke and Kirby (1994) reported that arbors of parasol ganglion cells that ramify in the middle layers of the inner plexiform layer (IPL) are transiently bistratified, becoming unistratified during late fetal periods. In this study I examined cells that ramify in the extreme inner and outer layers of the IPL, in fetal macaque, and compared their dendritic growth to cells ramifying in the middle IPL layers.

Timed dated fetal monkeys were delivered by C-section, euthanized, and their retinas rapidly removed and horseradish peroxidase stained using diaminobenzidine. Dendritic arbors were measured in wholemounts with quantification of the area and depth of …

The Periphyton Community Of A Second Order Subalpine Stream Following Salmon Carcass Decomposition, Jonathan Micheal Honea

Dissertations and Theses

To protect and manage Pacific Northwest salmonid stocks, sound management programs must be developed that incorporate knowledge of the ecological processes critical to their survival. One such process is the nutrient dynamic in headwater spawning streams. It is essential that we understand the trophic relationships among the spawners, the I to 3 year-old juveniles, the invertebrates, and the primary producers in these streams.

The hypothesis that I tested is that photoautotrophic production increases due to the decomposition of salmon carcasses. Increased primary production would stimulate the production of invertebrates which are an important food resource of juvenile salmonid species. The …

Semipermeable Membrane Devices Are Effective Surrogates Of Fish In Concentrating Polychlorinated Biphenyls, Christopher Gardner Collins

Master's Theses

This study examined the effectiveness of Semipermeable Membrane Devices (SPMDs) as surrogates for fish in concentrating polychlorinated biphenyls. Golden shiners (Notemigonus crysolucas) and SPMDs were exposed to three different concentrations (0.5, 1.5, and 3.0ppm) of Aroclor 1254 for 1, 3, and 5 days under laboratory conditions. Concentrations of Aroclor 1254 were measured in the SPMDs and fish tissue using extraction techniques and gas chromatography. The concentrations of PCB in SPMDs and N. crysolucas were positively correlated. This relationship compared favorably with data from other studies. The relationship between the concentration of PCB in SPMDs and tissue offish and …

The Role Of Cold Acclimatization On The Biogeography Of The Mountain Chickadee (Parus Gambeli) And The Juniper Titmouse (Parus Ridgwayi), Sheldon J. Cooper

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Biogeographic patterns of animals are shaped by biotic interactions, such as competition, and by abiotic factors, such as climate. Mountain Chickadees (Parus gambeli) and Juniper Titmice (Parus ridgway) are permanent residents of regions of western North America and are ecologically similar, but have different northern range limits. l measured several physiological variables, including basal metabolic rate (BMR), peak metabolic rate (PMR = maximal thermogenic capacity), metabolic response to varying environmental temperature (MRT), evaporative water loss (EWL), and daily energy expenditure (DEE) for summer-and winter-acclimatized Mountain Chickadees and Juniper Titmice to determine if seasonal and interspecific variation in cold tolerance and …

Exploring The Structure And Function Of The Snf1 Kinase Gene In The Slime Mold Dictyostelium Discoideum, Bryan Donald Whitemarsh

Undergraduate Honors Capstone Projects

All organisms must respond to different environmental stresses. For unicellular organisms, the most important source of stress is starvation or nutrient depletion. These microscopic life forms must respond to a constantly changing food supply in which short periods of nutrient availability are interspersed with extended periods of famine. In addition to complete starvation, these organisms are affected by other chemical changes, such as forced switching from a desirable to a less desirable carbon source, and physical changes, such as heat shock. Many microorganisms respond to such stresses by entering a different phase of their life cycle. For example, the budding …

Homology Among The Autosomal Chromosomes Of Boophilus Annulatus (Say) And B. Microplus (Canestrini), Bonnie S. Gunn

Theses and Dissertations - UTB/UTPA

Autosomes of Boophilus annulatus and B. microplus were compared using C- and G-bands to establish the degree of homology. Karyotypes of both species consisted of 20 autosomes and an XX:XO sex determination system with the X being the largest chromosome. All chromosomes of B. annulatus were acrocentric with heterochromatin limited to centromeric regions. The B. microplus karyotype was acrocentric with one band of noncentromeric heterochromatin occurring in three chromosome pairs. Interspecific comparisons indicated seven pairs of G-band homologous autosomes and three G-band homologous pairs when added interstitial heterochromatin was considered. The number three chromosome of both species showed variation in …

Evolutionary Genetics Of Canyon Treefrogs (Hyla Arenicolor), Roy A. Murray

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Population genetics is the study of the mechanisms that cause genetic change in populations over time. Genetic changes may lead to both adaptive evolution and speciation. While the former process is fairly well understood, many questions remain unanswered with regard to the process of speciation. How important is population isolation in the process of speciation? How long must populations be isolated before speciation is complete? Are the genetic changes that take place during speciation caused mainly by natural selection or does genetic drift play a substantial role? Can genetic drift alone lead to reproductive isolation? These types of questions have …

Interaction Of The Human Serine Protease Inhibitor Alpha-1-Antitrypsin With Cryptosporidium Parvum, John Russell Forney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The human serine protease inhibitor (serpin) alpha-1-antitrypsin (AAT) was studied for potential interaction with components of the protozoan parasite Cryptosporidium parvum. A homogenate prepared from C. parvum oocysts was incubated with purified human AAT, and complexes formed between the serpin and components of the homogenate were detected using an enzyme-linked immunosorbent assay (ELISA). Serpin:parasite infections were effectively blocked by preincubating AAT with a cognate target enzyme, porcine pancreatic elastase, prior to performing the ELISA on the homogenate. Incubation of a mixture of C. parvum oocysts and sporozoites with AAT demonstrated preferential fluorescence labeling of the sporozoite surface membrane by indirect …

Analysis Of The Inheritance Repression Of A Transposable Element In Drosophila Melanogaster, Melissa Leone

Master's Theses

No abstract provided.

The Soybean Retroelement, Sire-1, Encodes An Envelope-Like Protein-Sire-1 Is An Endogenous, Proretrovirus-Like Genomic Element, Arpita Majumdar

Master's Theses

No abstract provided.

Regulation Of The Activities Of The Three Nitrate Reductase Isoforms In Wild-Type Soybean Glycine Max (L.) Merr. (Variety Williams) By Protein Phosphorylation, Maribel T. Joson

Master's Theses

No abstract provided.