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Pathogenesis, Pathology And Chemotherapy Of Experimental Legionella Pneumophila Infection, Arthur O. Tzianabos
Pathogenesis, Pathology And Chemotherapy Of Experimental Legionella Pneumophila Infection, Arthur O. Tzianabos
Doctoral Dissertations
Legionella pneumophila is the causative agent of a severe, often fatal pneumonic illness known as Legionnaires' disease. The mechanisms by which L. pneumophila attaches to U937 (transformed human-like fibroblasts) were investigated. Experimental parameters for adherence assays were established prior to blocking studies designed to identify microbial adhesins and/or eukaryotic receptors that mediate bacterial attachment to target cells. Results from these studies indicated that a lectin-like component(s) associated with L. pneumophila may be responsible, at least in part, for microbial adherence to these eukaryotic host cells. Erythromycin is the drug of choice for the treatment of clinical legionellosis; however, difficulties with …
Changes By Accident Or Design: An Analysis Of Trends In American Nursing From A Feminist Perspective (1870-1988), Gloria Giaveno Straughn
Changes By Accident Or Design: An Analysis Of Trends In American Nursing From A Feminist Perspective (1870-1988), Gloria Giaveno Straughn
Doctoral Dissertations
This exploratory study analyzed trends in American nursing from 1870-1988. The study used three kinds of graphical analysis (timeplots, scatterplot matrices and residual plots) to informally test fifteen hypotheses regarding nurse supply. Nurse supply was broken into two categories: nurse requirement, or the actual number of nurses employed in nursing at any one point in time; and nurse availability, or the potential number of new nurses needed to be produced or recruited. The hypotheses focused on two broad empirical research questions: "How many nurses are there?" and "How many nurses are enough?" Feminist conceptual frameworks were employed to inform the …
Factors Associated With Root Caries Initiation, David William Banting
Factors Associated With Root Caries Initiation, David William Banting
Digitized Theses
Forty institutionalized adults, considered to be at high risk of root caries, were followed for a two year period. They were grouped according to whether the microorganisms under study (Streptococcus mutans, Streptococcus sanguis, Actinomyces viscosus, Actinomyces naeslundii and Lactobacillus) were present at baseline on one or more noncarious root surfaces with gingival recession and the incidence of root caries was then recorded. The null hypothesis was that the presence of these microorganisms is not associated with the occurrence of root caries. The effect of other variables shown to be associated with root caries, such as age, sex, number of teeth, …
Studies On Adenosine-Mediated Neuromodulation In The Enteric Nervous System, Fedias Leontiou Christofi
Studies On Adenosine-Mediated Neuromodulation In The Enteric Nervous System, Fedias Leontiou Christofi
Digitized Theses
Although the role of adenosine in the inhibition of acetylcholine release from myenteric neurons of the small intestine is firmly established, the classification and characteristics of such receptors have not been adequately described. Unlike in the central nervous system, it is not clear if heterogeneity of adenosine receptors exists, or if nucleoside-mediated inhibition of the release of other neuromediators occurs in the enteric nervous system. The studies reported in this thesis were directed at these questions.;Adenosine recognition sites were characterized in ligand binding studies at purified myenteric varicosities. The receptor nature of the binding sites labelled by selective adenosine analogs …
The Morphology And Contractile Function Of Skeletal Muscle In Aged Humans, Charles Leslie Rice
The Morphology And Contractile Function Of Skeletal Muscle In Aged Humans, Charles Leslie Rice
Digitized Theses
Muscle strength and morphology were investigated in four studies in elderly men and women between the ages of 62 and 102 years. The purposes were to: (1) measure the voluntary strength in several limb muscle groups from an 'older' elderly population, (2) measure and compare the amount of muscle and non-muscle tissue (NMT) in the arms and legs of older (65 + years of age) and younger (25 to 38 years of age) males using computed tomography (CT) scans, (3) compare the CT results with measures of anthropometry in the same two groups of males, and (4) measure the electrically …
Characterization Of Immunoregulatory Cells And Factors Derived From Normal Human Bone Marrow, Franco Mortari
Characterization Of Immunoregulatory Cells And Factors Derived From Normal Human Bone Marrow, Franco Mortari
Digitized Theses
The bone marrow is a primary lymphoid organ whose main function is to provide a continuous source of hematopoietic cells to the peripheral immune system. This study was undertaken to elucidate the roles of bone marrow cells and their mediators in immunoregulation.;Fractionation of bone marrow cells resolved two distinct immunoregulatory activities. A population of bone marrow cells of the phenotype HNK-1{dollar}\sp{lcub}+{rcub}{dollar} (human natural killer cell antigen, CD57), SSEA-1{dollar}\sp{lcub}+{rcub}{dollar} (stage specific embryonic antigen) and OKM1{dollar}\sp{lcub}+{rcub}{dollar} (human monocyte antigen, CD11B) was found to be highly suppressive for primary antibody responses. Conversely, a lymphocyte enriched bone marrow cells fraction could enhance the same …
Investigation Of The Mechanism Of Contraction Of The Isolated Guinea Pig Pulmonary Venule Induced By Hypoxia Or Anoxia, Wayne Ross Tracey
Investigation Of The Mechanism Of Contraction Of The Isolated Guinea Pig Pulmonary Venule Induced By Hypoxia Or Anoxia, Wayne Ross Tracey
Digitized Theses
Since small pulmonary arteries are thought to be the major site of hypoxic pulmonary vasoconstriction (HPV), the response of pulmonary veins to hypoxia has not been thoroughly investigated. Therefore, the response of isolated guinea-pig pulmonary venules to hypoxia (bath Po{dollar}\sb2{dollar}: 25 torr) and anoxia (bath Po{dollar}\sb2{dollar}: 0 torr) was characterized. Pulmonary venules (effective lumen radius (ELR): 119 {dollar}\pm{dollar} 1 {dollar}\mu{dollar}m) responded to hypoxia and anoxia with a graded, sustained, and repeatable contraction (hypoxia: 3 {dollar}\pm{dollar} 1 mg/mm; anoxia: 27 {dollar}\pm{dollar} 3 mg/mm), while paired femoral venules (ELR: 184 {dollar}\pm{dollar} 7 {dollar}\mu{dollar}m) contracted to the initial anoxic challenge only (5 {dollar}\pm{dollar} …
Postmenopausal Osteoporosis: Characterisation Of An Animal Model And The Effects Of Dietary Calcium, Darien-Alexis Veronica Lazowski
Postmenopausal Osteoporosis: Characterisation Of An Animal Model And The Effects Of Dietary Calcium, Darien-Alexis Veronica Lazowski
Digitized Theses
Postmenopausal osteoporosis is a debilitating condition which affects 25% of Caucasian women. To date, neither prophylaxis nor treatment have met with any great success. Calcium supplementation (CaSuppl) has been widely advocated in the prevention and treatment of osteoporosis despite the paucity of scientific evidence suggesting that calcium has any beneficial effect. We have employed an oophorectomised rat model to investigate the effects of oestrogen deficiency on the skeleton and bone marrow. In this laboratory approach it was also possible to examine the effects of calcium in this model.;Adult female rats were either oophorectomised or sham operated, and fed either a …
Investigations Of The Mechanism Of Alcohol-Induced Cardiomyopathy, David Christopher King
Investigations Of The Mechanism Of Alcohol-Induced Cardiomyopathy, David Christopher King
Digitized Theses
Investigations into the mechanism of severe, subacute ethanol induced cardiomyopathy in the rat were performed in animals that were severely intoxicated for 48 hours. This treatment produced increases in cardiac wet weight, dry weight and protein content. Determination of cardiac DNA content and water content showed that the increase in heart size resulted from hypertrophy and not hyperplasia nor edema.;In a time effect study of intracellular events it was found that cardiac ornithine decarboxylase activity was enhanced after eight hours of intoxication and remained elevated through 24 hours. RNA content was elevated by eight hours and remained high through the …
The Effects Of High Pressures Of Inert Gases And Of Anaesthetics On Rat Striatal Dopamine In Vitro, Margaret Lorraine Paul
The Effects Of High Pressures Of Inert Gases And Of Anaesthetics On Rat Striatal Dopamine In Vitro, Margaret Lorraine Paul
Digitized Theses
Operational deep-sea diving is complicated by two conditions affecting the Central Nervous System. One of these, known as Inert Gas Narcosis (IGN), is due to the presence of nitrogen (N{dollar}\sb2{dollar}) in the breathing gas, and presents signs and symptoms of progressive CNS depression similar to anaesthesia as pressure (depth) is increased. The other, referred to as the High Pressure Neurological Syndrome (HPNS) was observed when non-narcotic helium (He) was substituted for N{dollar}\sb2{dollar} to circumvent the problem of IGN. The effects are attributed to pressure per se and include, in man, tremor, EEG changes, and motor incoordination. The precise neurological changes …
Studies On The Factors Affecting The Renal Toxicity Of Cadmium Metallothionein And Cis-Diamminedichloroplatinum, Catherine Ann Suzuki
Studies On The Factors Affecting The Renal Toxicity Of Cadmium Metallothionein And Cis-Diamminedichloroplatinum, Catherine Ann Suzuki
Digitized Theses
The critical organ of toxicity after chronic cadmium (Cd) exposure is the kidney. This toxicity can be modified by intracellular interactions of Cd with metallothionein (MT) or glutathione (GSH). Since the Cd-bound form of MT (Cd-MT) is a potent nephrotoxic agent, Cd-MT was used as a model for investigations of Cd-induced renal disease.;After Cd-MT injection in rats, urinary enzymes were used as subcellular markers of renal damage. The maximal excretion of two brush border membrane (BBM) enzymes preceded the maximal excretion of a lysosomal enzyme indicating early damage to the BBM with subsequent lysosomal damage. Pretreatment with zinc (Zn) increased …
Antigen-Specific Ige Suppression Induced By Immunization With Dinitrophenyl-Bordetella Pertussis Is Mediated Through Interferon-Gamma, Michael Hagen
Antigen-Specific Ige Suppression Induced By Immunization With Dinitrophenyl-Bordetella Pertussis Is Mediated Through Interferon-Gamma, Michael Hagen
Digitized Theses
Immunization of mice with dinitrophenyl-Bordetella pertussis (DNP-BP) failed to induce anti-DNP IgE responses. Administration of DNP-BP induced however, the formation of anti-DNP IgE B memory cells, as demonstrated by adoptive transfer. Furthermore, mice pretreated with DNP-BP and primed with 2 {dollar}\mu{dollar}g DNP-OA in alum 2 weeks later produced high day 7 anti-DNP IgE levels. These subsided to near undetectable levels by day 12-14. The transient expression of serum IgE levels was accompanied by normal levels of anti-DNP IgG. The anti-OA response induced as a result of priming with DNP-OA in alum was not affected by pretreatment with DNP-BP. IgG subclass …