Life Sciences Commons^™

Characterization Of Steroid-17,20-Desmolase And 20Α-Hydroxysteroid Dehydrogenase From Clostridium Scindens, Amy Elizabeth Krafft

Theses and Dissertations

Clostridium scindens is an obligate anaerobe isolated from the normal intestinal flora of man. It is the only bacterium known at present to synthesize both steroid-17,20-desmolase and 20α-hydroxysteroid dehydrogenase (ZOα-HSDH). This study was undertaken to characterize these neutral steroid transforming reactions in extracts of C. scindens; to purify and characterize the enzymes responsible for side-chain cleavage and 20α- hydroxysteroid oxidoreduction and to clone the genes encoding these enzymes with a view towards studying the mechanism of induction by steroids in a prokaryotic system. Both enzymes were found to be co-inducible in cells cultured in the presence of 17α-hydroxysteroids. In cell …

Proliferation And Differentiation Of Mast Cell Progenitors, Daniel Lee Jarboe

Theses and Dissertations

We have identified a late, committed stage in the differentiation of the mast cell progenitor just prior to granulation. This mast cell-committed progenitor (MCCP) differs from the more primitive bone marrow mast cell progenitor in that it is able to proliferate and differentiate in the absence of interleukin-3 (IL-3) when cultured on a monolayer of embryonic skin or 3T3 fibroblasts. The MCCP can be harvested from the mesenteric lymph nodes of mice in their fourteenth day of infection with the rodent hookworm Nippostrongylus brasiliensis and can be cloned in a methylcellulose culture system by supplementing the cultures with fibroblast-conditioned medium …

Phenotypic And Functional Characterization Of Ia+ And La- Sublines Of The Human Monocyte-Like Cell Line, U937, Coles Meredith Squire

Theses and Dissertations

Sublines were derived from the U937 human monocytic cell line by limiting dilution techniques. Several of the sublines derived in this manner were found to constituitively express la, unlike most U937 cell lines previously examined. Thus the la+ and la- sublines were examined and characterized phenotypically and functionally. Morphologically the sublines, both la+ and la-, were found to be similar to the originally described U937 parent cell line. They were positive for production of non- specific esterase and expressed the HLA phenotype A(3,X), B(51,18), DR(2,X). The sublines were examined by immunofluorescence techniques with a large number of antibodies specific for …

Aspects Of Bald Eagle Winter Behavior In Rush Valley Utah: A Telemetry Study, Neil B. Sabine

Theses and Dissertations

The diurnal behavior and nocturnal roosting patterns of 28 bald eagles outfitted with tail-mounted radios were investigated in Rush Valley, Utah between January and March 1982-1984. Casting analysis and feeding observations indicated the principal food source was jackrabbit carrion. Jackrabbit availability declined from 1982 to 1984 and eagles responded by; 1) roosting closer to feeding sites, 2) shifting from canyon to valley roosts, 3) arriving later at and departing earlier from roosts, 4) decreasing diurnal activity, and 5) decreasing residence time. Foraging efficiency appeared to be maximized by experienced eagles using familiar feeding areas and by naive birds monitoring their …

Assessment Of Influence That The Church Of Jesus Christ Of Latter-Day Saints Has On Exercise Habit Of Members Living In Utah County, Gary L. Preston

Theses and Dissertations

This study identified and analyzed the influence the Church of Jesus Christ of Latter-day Saints had on the decision of 309 respondents to exercise. The data obtained from the questionaires were analyzed using chi-square to compare males and females. Within the limitations of this study, the following conclusions were justified: women were more influenced by the LDS Church to exercise than men; LDS males and females exercised more than average American adults; walking, jogging, and aerobic dance were the most popular choices of LDS exercisers; and, there is a need to improve the awareness of LDS members concerning the Physical …

Effects Of Hematocrit Variations On Microcirculatory Hemodynamics And Oxygen Transport In Hamster Striated Muscle, Lih Kuo

Theses and Dissertations

Experiments were performed to investigate the influence of isovolemic hemodilution and hemoconcentration on microcirculatory hemodynamics and oxygen transport in the hamster cheek pouch retractor muscle. Measurements of red blood cell velocity, microvessel hematocrit, vessel diameter, segment length (L), hemoglobin oxygen saturation (SO₂) and longitudinal SO₂ gradient (ΔSO₂/L) were made in four arteriolar branching orders before and after isovolemic exchange with plasma (hemodilution) or packed red blood cells (hemoconcentration).

In the study of hemodilution, systemic hematocrit was reduced from 52 to 33% in 23 hamsters. This degree of hemodilution resulted in an average decrease in microcirculatory …

Degradation Of Human Anaphylatoxin C3a By Rat Peritoneal Mast Cells: A Role For The Secretory Granule Enzyme Chymase And Heparin Proteoglycan, James Edmund Gervasoni Jr

Theses and Dissertations

Purified human C3a was iodinated (¹²⁵I-C3a) and used to study the interaction of labeled peptide with rat peritoneal mast cells (RMC). Cellular binding of ¹²⁵I-C3a occurred within 30 sec, followed by a rapid dissociation from the cell. Both the binding of ¹²⁵I-C3a and the rate of dissociation from the cell were temperature dependent. At 0°C, the binding of ¹²⁵I-C3a was increased and the rate of dissociation reduced, as compared to 37°C. Once ¹²⁵I-C3a was exposed to RMC, it lost the ability to rebind to a second batch of RMC. Analysis of the supernatants by …

Characterization Of A Staphylococcal Trimethoprim Resistance Gene, Jerald Preston Coughter

Theses and Dissertations

Trimethoprim resistance(Tp r) is encoded by conjugative plasmids in clinically significant staphylococcal isolates. Two genetically and physically similar plasmids from S. aureus, pG01 and pGOS, have Tp r genes that map in different locations on these plasmids. In order to study the relatedness of the Tp r genes and their products to other known Tp r genes, a 1.2 kb fragment of pG01 and a 4.2 kb fragment of pGOS were cloned in E. coli and used as probes for in situ filter hybridization experiments.

A 500 base pair subclone of the original 1.2 kb fragment containing only the staphylococcal …

Proliferation Of Schwann Cells Induced By Axolemmal And Myelin Membranes, Michael Paul Dinneen

Theses and Dissertations

Purified Schwann cells were cultured from neonatal rat sciatic nerve using a modification of the method of Brockes (Brockes, J.P. et al, Brain Res. 165(1979) 105-118). Schwann cells and contaminating fibroblasts were unambiguously identified using fluorescent antibodies to 2'3' cyclic nucleotide 3'-phosphodiesterase and the thy 1.1 antigen respectively. The Schwann cells were quiescent unless challenged with mitogens, They proliferated rapidly in response to the soluable mitogen, cholera toxin, or to membrane fractions from rat CNS or PNS, prepared by the method of DeVries (DeVries, G.H., J Neurochem, 40 (1983) 1709-1717). Mitogenic activity was present in both axolemmal and myelin enriched …

Dissection Of Microphage Activation Using T Cell Hybridoma Derived Lymphokines, William S. Futch Jr.

Theses and Dissertations

Macrophage phenotype/function can be modulated by various T-cell lymphokines (LK). The alteration of macrophage phenotype is a result of LK concentration, duration of exposure, and the level of macrophage activation when obtained from in vivo sources through elicitation by either sterile irritants or immune cellular mechanisms. In order to dissect macrophage activation into discrete signals T cell hybridomas were constructed by fusing HAT sensitive BW5147 cells with nylon-wool purified, con A stimulated T cells. The resulting T cell hybrids were screened for their ability to: (a) protect macrophages from the cytopathic effect of Naegleria; (b) induce class II MHC gene …

A Nutritional And Morphological Study Of Two Cyanobacteria Free Azolla Ferns, Michael Paul Bonner

Theses and Dissertations

The symbiotic association between the aquatic water fern Azolla and its symbiont, Anabaena azollae Straus. has been extensively studied in the past ten years. The cyanobacteria has received much of the attention due to its ability to fix atmospheric nitrogen while the fern free of the cyanobiont has been somewhat neglected. The purpose of this research was to determine the nutritional requirements of the cyanobacteria free (CBF) ferns and study the morphology of the leaves and branches of these CBF ferns.

Azolla filiculoides and Azolla pinnata were freed of the cyanobiont using the surface sterilization technique adopted from Duckett, et …

Coxsackievirus B4 Induced Diabetes In Cd-1 Mice, Mary C. F. Anderson

Theses and Dissertations

Most evidence to date clearly indicates that CB4 virus can affect the pancreas of both man and mice during acute infection. Yet, conflicting evidence exists relative to the consequence of the infection in both man and mice. The study described here attempted to provide definitive evidence on the relative role of the virus isolate (i.e. heterogenous virion populations vs. purified clones) in induction of prolonged diabetes-like disease in mice.

Effects Of Pulsed Electric Fields On Mammalian Cell Membranes, Guy K. Smith

Theses and Dissertations

The effect of pulsed electric fields on cell membranes were studied to investigate the effects of an electric field, per se, on biological systems, without the densometric and other technical problems associated with other forms of nonionizing radiation. Exposure of mouse splenocytes to a high voltage pulse resulted in an increase in membrane permeability to K⁺ that was dependent on both the electric field strength and the pulse duration. Exposure to a 2 μsec, 3.0 kV/cm pulse elicited a 50% loss of intracellular K⁺ indicating that the critical transmembrane potential (V_m) at breakdown was 1.26 volts …

An Evaluation Of The Central Neurotoxic Effects Of Aroclor 1254, A Commercial Mixture Of Polychlorinated Biphenyls, In Mice, Diane L. Rosin

Theses and Dissertations

Polychlorinated biphenyls (PCBs) are industrial compounds whose ubiquitous environmental contamination has been known since the late 1960's. Incidents of human intoxication have been reported, most notably, the "Yusho" incident that affected over 1600 people in Japan in 1968. A broad spectrum of adverse effects are produced by PCBs, including some neurological symptoms. While examination of the toxic effects of PCBs has received much attention, there has been little work on the neurotoxicity of PCBs. The intent of the experiments presented in this thesis is to provide further information on the central neurotoxicity of PCBs in mice.

A commercial mixture of …

Nuclear Envelope Proteins: Chemical Characteristics And Molecular Interactions Of The Lamins, David Lee Cochran

Theses and Dissertations

The lamins are a group of proteins in a residual nuclear envelope fraction derived from the nuclear lamina. The absence of specific functional assays for the two predominant species, lamin A and lamin B, has complicated their biochemical characterization. Initial studies reported in this work involved the enzymic cleavage of isolated lamins A and B and another lamina protein with a molecular weight of 61,000-daltons. The results obtained with each of three enzymes indicated strong similarities between the three nuclear envelope proteins.

Further chemical characterization of the lamins has been achieved. Lamins A, B and C have been separated by …

Enflagellation Of Naegleria Fowleri, Terry Wayne Woodworth

Theses and Dissertations

Organisms of the genus Naegleria differentiate from feeding, dividing amebae into temporary swimming flagellates when deprived of nutrients. Factors critical for enflagellation of the pathogenic species, N. fowleri, were delineated and optimal conditions established for evoking reproducible conversion of N.fowleri populations. N. fowleri enflagellation differed from that of N. gruberi in its dependence upon growth phase, population density during enflagellation and in the timing and extent of the conversion. N. fowleri amebae from stationary phase cultures grown at 37°C, washed free of medium and suspended in nutrient~free ameba saline, acquired flagella and converted to mature flagellates in a synchronous manner …

Multivariate Analyses Of Mid-Winter Fattening In Two Species Of Passerine Birds, Michael Harold Shelor

Theses and Dissertations

Although the adaptive significance of daily and seasonal fattening of birds has been studied by many investigators (see Odum, 1965; King, 1972; Blem, 1976a), surprisingly little is known about the interactions of proximate and ultimate environmental factors regulating avian lipid levels. An exception is the study by Evans (1969). He found that lipid levels in Yellow Buntings (Emberiza citrinella) were more closely correlated with long-term temperature averages than with temperatures of the day of capture, or the days preceding or following capture. This is an indication that temperature may be more important as an ultimate control of fattening, through natural …

Genetic Studies Of Questionnaire Data From A Residential School For The Deaf, Frederick Robert Bieber

Theses and Dissertations

A self-administered thirteen page Hearing Loss Questionnaire (HLQ) was designed in order to systematically collect medical and family history data on deaf children and their families. Data were collected from over 400 families with one or more children enrolled in September 1979 at the Maryland School for the Deaf (MSD). Almost 70% of the parents provided pedigree and family history information by completing the detailed HLQ. Computer analyses of the collected data allowed a thorough examination of almost 200 medical and family history variables, providing useful reference data on the MSD probands. Parental responses to a four-step rating scale of …

Solubilization And Partial Characterization Of An Activity Regulating Complement Activation From Membranes Of Raji And Tonsil Cells, Patricia L. Carlson

Theses and Dissertations

Complement is one of the major innate nonspecific mechanisms for host defense in serum. More than a dozen proteins have been isolated from serum which have a function in either the activation or regulation of complement action. Complement is similar to the coagulation sequence in that it comprises a number of precursor proenzymes in plasma that are sequentially cleaved to generate biologically and enzymatically active proteins.

The Role Of Retained Antigen As An Etiological Agent In Rheumatoid Arthritis, Patricia Liccardi Rice

Theses and Dissertations

The cause(s) of arthritis and many other connective tissue diseases are largely unknown. An infectious agent, either bacterial or viral, has not been unequivocally isolated. Theories on the pathogenesis of arthritis abound. Many of these theories implicate the immune system as the problem.

The early information on animal arthridites implicates retained bacterial cell wall antigens as the basis of the arthritis seen. How-ever, numerous types of antigens, both complex polymers and simple proteins, have been shown to persist in immune animals. The antigens persist in the lymph nodes and spleens playing a role in mediating antibody feedback mechanisms. Antigens also …

Effects Of Glucocorticoid Treatment On The Properties Of Single Notor Units In Cat Hindlinb Huscles, Andrew James Robinson

Theses and Dissertations

The administration of glucocorticoids has been shown to induce atrophy and weakness in whole skeletal muscle. These effects frequently appear to be more pronounced in pale muscle than in red muscle. The present study was undertaken to examine the effects of steroid treatment on the contractile, electrical, and fatigue properties of single meter units in pale and red cat hindlimb muscles. Single motor units in the medial gastrocnemius (MG) and soleus muscles were isolated using techniques developed by McPhedran, et al., (1965). The properties of a large number of motor units were examined in normal animals and were compared to …

The Chronic Effects Of Estradiol Benzoate On Ventricular Myocardial Blood Flow In The Adult Female Rat, Stephen Maurice Ashe

Theses and Dissertations

Clinical and experimental data suggest that humans and some animals are protected from acute myocardial infarction by estrogen. There has been much speculation of the exact role which estrogen plays in the circulation. The mechanism of this hormonally related protection is unclear.

In the present study the chronic effects of estradiol benzoate on coronary blood flow in adult female rats were studied. Female control rats, castrates and castrates receiving estrogen for a period of 16 weeks were used. In vivo tracer microsphere studies of myocardial blood flow allowed the quantification of the effects of estrogen on coronary circulation. Results of …

An Analysis Of The Fit Of The Negative Binomial Distribution To Frequencies Of Episodes Of Illness, Philip Melville Brennan Jr.

Theses and Dissertations

In recent years, much interest has been shown in "modeling," or fitting, primary care data to known statistical distributions. Specifically, much work has been done in studying the distributions of episodes of illness and consultations in family practices. This thesis will examine the utility of the negative binomial distribution's fit to family practice data.

Genetic Heterogeneity In Complementation Groups Of Propionic Acidemia, Catherine Mckeon

Theses and Dissertations

Propionic acidemia is an autosomal recessively inherited disorder of organic acid metabolism caused by deficient activity of propionyl CoA carboxylase. This enzyme is required for the catabolism of the odd-chain fatty acids, the side chain of cholesterol and the amino acids: isoleucine, methionine, and threonine. Although the clinical expression of this disorder is variable, affected children usually develop ketoacidosis and hyperammonemia which may progress to seizures, coma and possibly death. Some patients may exhibit vomiting, lethargy and hypotonia in the first few weeks of life whereas others may remain asymptomatic for months or even years.(1) The degree of residual enzyme …

Psychopharmacological Analysis Of Central Muscarinic And Nicotinic Receptors, Leonard T. Meltzer

Theses and Dissertations

Arecoline and nicotine are two psychoactive cholinergic alkaloids. Arecoline is primarily a muscarinic agonist while nicotine, at low doses, is a nicotinic agonist. The experiments in this dissertation investigated two major areas: (1) the role of different factors in the development of tolerance to the behavioral effects of arecoline and nicotine, and (2) the possible mechanism and site of action of the discriminative stimulus (DS) effects of arecoline and nicotine.

The role of dispositional and physiological factors comfiared to behavioral factors in the development of tolerance to the effects of arecoline and nicotine on operant behavior was assessed in Experiments …

An Interphysiographic Analysis Of Herb And Shrub Vegetation In Virginia Forests, Stephen James Binns

Theses and Dissertations

Thirty upland deciduous stands were sampled from the mid-coastal Plain to the mid-Piedmont in New Kent, Hanover, and Louisa Counties. Density data for herb and shrub species were collected and soil samples were collected in each stand. A cluster analysis of the vegetation data was performed using Euclidean Distance and "furthest-neighbor" clustering. Four clusters of stands were identified. A cluster of six stands with Euonymus americanus as the dominant species was strongly related to the Coastal Plain, but the other clusters were not physiographically associated. Other important species in the analysis were Vaccinium vacillans, Gaylussacia baccata, and Mitchella repens.

The …

Efficacy Of Salinomycin On Infections Of Plasmodium Berghei In Male Icr Mice, Anthony Stephen Tokarz

Theses and Dissertations

The objective of this study was to determine whether or not salinomycin, a drug with proven effectiveness against intestinal sporozoan parasites, has any effect on the survival time of mice infected with P. berghei.

Antiviral Activity Of Peritoneal Exudate Cells Of Mice Against Infection With Herpes Simplex Virus Type 2, Margaret Byrd Mcgeorge

Theses and Dissertations

Within the past decade, there has been increasing evidence which suggests that herpes simplex virus type two (HSV-2) is associated with cervical carcinoma. Because cancer of the cervix ranks as the second most common malignant disease of women, with 35 thousand new cases and 10,000 deaths per year, further investigation is warranted to determine if there is a causal relationship (Goldberg, 1976). Currently, most of the evidence which correlates HSV-2 with cancer of the cervix has been, for the most part, indirect: (i) there is an increased incidence of cervical anaplasia in women with cytologically detectable genital herpes infection, (ii) …

Characterization Of The Bursicon-Mediated Pathway For Membrane Permeability Enhancement In The American Cockroach, Periplaneta Americana, David Alan Compton

Theses and Dissertations

The presence of an adenyl cyclase system within the haemocyte of Periplaneta americana has been confirmed by previous investigations, with corresponding experiments using dibutyryl cyclic AMP to show enhancement of 14c-tyrosine uptake into the cuticle linked to stimulation of the sclerotization process.

In the present studies, American cockroaches held at depressed temperatures were treated with bursicon, revealing an increase in haemocyte cyclic AMP concentrations. The levels declined with progression of time, probably resulting from enzymatic hydrolysis.

When animals which had been held at room temperature were treated with bursicon, the levels of haemocyte cyclic AMP were lowered, with a declination …

The Effects Of Streptozotocin-Induced Diabetes On Responses To Opiates And Other Centrally-Acting Pharmacologic Agents, Glenn Stuart Simon

Theses and Dissertations

Diabetes mellitus affects millions of people. Although diabetics can lead relatively normal lives, all treatments for the disease are symptomatic and not curative. The purpose of this investigation was to determine whether the sensitivity to opiates and other selected centrally-acting drugs in animals is altered by streptozotocin (STZ)-induced diabetes. A second objective was to determine which aspect of the diabetic syndrome primarily was responsible for the altered sensitivity. Other experiments were performed in an attempt to elucidate the mechanism whereby this altered sensitivity occurred.

STZ-induced diabetes or dextrose-induced transient hyperglycemia did not have a significant effect on the duration of …