Thesis (Ph.D.)--Ohio University, November, 2008. / Title from PDF t.p. Release of full electronic text on OhioLINK has been delayed until December 1, 2010. Includes bibliographical references (leaves 140-162)

Thesis (Ph.D.)--Cleveland State University, 2009. / Abstract. Title from PDF t.p. (viewed on Sept.8, 2009). Includes bibliographical references (p. 101-104). Available online via the OhioLINK ETD Center and also available in print.

Thesis (M.S.)--The University of North Carolina at Greensboro, 2009. / Directed by Mark Hens; submitted to the Dept. of Biology. Title from PDF t.p. (viewed May 17, 2010). Includes bibliographical references (p. 60-65).

Thesis (M.Phil.) - University of St Andrews, January 2008.

Thesis (Ph.D.)--Ohio University, November, 2008. / Release of full electronic text on OhioLINK has been delayed until December 1, 2010. Includes bibliographical references (leaves 140-162)

Abstract The aim of the study was to evaluate pulmonary endogenous and inhaled nitric oxide (NO) in neonates with severe respiratory failure. Infant autopsy documents were reviewed for fulminant early-onset bacterial pneumonia. 12 infants with the onset at < 72 h of age and three control groups were identified. Immunohistochemistry revealed that 11 of the infants with early-onset pneumonia (92%) had no or faint inducible nitric oxide synthase (NOS2) staining in their alveolar macrophages (AM). All control infants, regardless of their postnatal age, had NOS2-positive AM. The marker of NO-toxicity, nitrotyrosine, was low in all specimens. To confirm this finding, airway specimens of 21 newborns requiring mechanical ventilation were examined. Seven of them had fulminant early-onset pneumonia with maternal ascending intra-uterine infection (IUI). The controls had no infection at birth despite IUI or neither infection nor IUI. In early-onset pneumonia, NOS2 and nitrotyrosine immunoreactivity were low at birth and increased during the recovery phase (p < 0.05). Analyses of interleukin-1 and surfactant protein A showed the same pattern of age-dependent change. Of the autopsied infants, 12 had received inhaled NO (iNO) before death. Each case was paired with a matched control. Additional five infants without respiratory failure prior to death were also studied. The iNO-treated ones tended to have more intensive NOS2 staining in the bronchiolar epithelium and adjacent tissue than the controls. No differences in other NOS isoforms or nitrotyrosine were detected. A novel method for exhaled NO measurements of intubated infants was developed. Six preterm and six term newborns were prospectively recruited for expired and nasal NO measurements. During the first week of life, the preterm infants showed a different pattern of exhaled NO excretion compared to the term infants. For the pilot intervention study on very early iNO, the eligible patients had a birth weight < 1500 g and progressive, therapy-resistant respiratory failure before five hours of age. Five infants received iNO, showed immediately improved oxygenation and survived without deleterious side effects. Deficient production of NO in small premature infants is associated with severe infection and respiratory failure. Very early iNO therapy may be exceptionally effective in a select group of infants, and did not appear to cause oxidation lung injury.

Catecholamines are elaborated in stress responses to mediate vasoconstriction, and elevate systemic vascular resistance and blood pressure. They are elaborated in disorders such as sepsis, cocaine abuse, and cardiovascular disease. The aim of the study was to determine whether catecholamines affect nitric oxide (NO) production, as NO is a vasodilator and counteracts the harmful effects of catecholamines. RAW264.7 macrophage cells were cultured with lipopolysaccharide (LPS)±epinephrine, norepinephrine, and dopamine at 5×10-6M concentrations for 24h. Supernatants were harvested for measuring NO by spectrophotometry using the Greiss reagent and cells were harvested for detecting inducible NO synthase (iNOS) by Western blot. NO production in RAW 264.7 macrophages was increased significantly by addition of LPS (0.5-10ng/ml) in a dose-dependent fashion. The NO production induced by LPS was further enhanced by epinephrine and norepinephrine, and to a lesser extent by dopamine. These increases in NO correlated with expression of iNOS protein in these cells. The enhancing effect of iNOS synthesis by epinephrine and norepinephrine on LPS-induced macrophages was down regulated by β-adrenoceptor antagonist, propranolol, and dexamethasone. The results suggest that catecholamines have a synergic effect on LPS in induction of iNOS synthesis and NO production, and this may mediate some of the vascular effects of infection. These data support a novel role for catecholamines in disorders such as septic shock and cocaine use, and indicate that β-adrenoceptor antagonists and glucocorticoids may be used therapeutically for modulation of the catecholamine-NO axis in disease states.

No description available.

The emergence of pesticide-resistant mosquitoes and drug-resistant parasites in the last twenty years has made control of malaria more difficult. One novel strategy to better control malaria is the development and release of transgenic mosquitoes whose enhanced immunity prevents transmission of the parasite to the mammalian host. One candidate effector gene is Anopheles stephensi nitric oxide synthase (AsNOS), whose inducible expression and subsequent synthesis of nitric oxide (NO) limits Plasmodium development in A. stephensi. In mammals, one of the most potent physiological regulators of NOS gene expression and catalytic activity is transforming growth factor-β (TGF-β). Moreover, human TGF-β can activate Drosophila melanogaster Smads, the proteins responsible for TGF-β signal transduction. We have determined that following a bloodmeal, active human TGF-β1 (hTGF-β1) persists in the midgut of A. stephensi for up to 48 hours. My data demonstrate that the midgut epithelium recognizes hTGF-β1 as an immunomodulatory cytokine. Specifically, induction of AsNOS by hTGF-β1 occurs in the midgut within minutes of bloodfeeding. Moreover, hTGF-β1 limits development of the human malaria parasite Plasmodium falciparum in the midgut. In other experiments, provision of the AsNOS catalytic inhibitor L-NAME partially reverses the effect of hTGF-β1 on Plasmodium development. These results suggest that AsNOS is a target of hTGF-β1 signaling and additional effectors that impact parasite development may be regulated by hTGF-β1 as well. The fact that hTGF-β1 signals mosquito cells to limit malaria parasite development suggests that there is an endogenous TGF-β signaling network in place. An analysis of the A. gambiae genome database revealed the presence of six TGF-β ligands, including gene duplication in the 60A gene, the first evidence of ligand gene duplication outside of chordates. In addition to five receptors, three Smads were identified in the A. gambiae genome predicted to support TGF-β/Activin- and BMP-like signaling. Midgut epithelial cells and an immunocompetent A. stephensi cell line express all three Smads, confirming that a signaling pathway is in place to support signaling by divergent exogenous and endogenous TGF-β superfamily proteins. The results presented here provide the first evidence of immunological crosstalk between divergent free living hosts of a single parasite. Further, these results imply that the interface between mammals and the mosquitoes that feed on them provide a unique opportunity for circulating molecules in the blood, including TGF-β and other cytokines, to alter the mosquito immune response. / Master of Science

First study determined the effects of genetic deletion of nNOS on the levels of spontaneous apoptosis in brain of young-adult (2-3 months) and aged (12-18 months) mice, using nNOS-knockout mice with age-matched B6129SF2/J mice as wild-type control. The results indicate that aging resulted in 11-fold increase in levels of apoptotic-DNA-fragmentation in B6129SF2/J mouse brain. nNOS-knockout mice demonstrated dramatic (72-fold) increases in levels of apoptotic-DNA-fragmentation in young-adult, but not aged, brains. Aging resulted in decreased number of nNOS-positive cells, increased number of iNOS-positive cells and no change of eNOS-positive cells in control mice. The data suggest that nNOS may serve an anti-apoptotic/neuroprotective role in young-adult mouse brain. However, because of diminished nNOS and increased iNOS with aging, this neuroprotective effect may become less effective in aged mice. / Fourth study showed that new microchip-electrophoresis-technology can be successfully used to identify and quantify levels of apoptosic-DNA-fragments in brain slice cultures, similar to our previous studies with CE-LIF. Because of the much greater throughput of microchip-electrophoresis-system, compared to CE-LIF, this new technology should help accelerate the progress of apoptosis research. / In second study, apoptotic effects of genetic deletion of either eNOS or iNOS were studied using young-adult (1-4 months) and aged (12-24 months) eNOS- or iNOS-knockout mice with age-matched C57BL/6J wild-type control mice. The data show that both young-adult and aged iNOS-knockout mice had dramatically (8- to 36-fold) higher levels of apoptotic-DNA-fragmentation compared to control, especially noticeable in hippocampus and medulla oblongata. Both young-adult and aged eNOS-knockout mice also had dramatically (18- to 35-fold) higher levels of apoptotic-DNA-fragmentation compared to control, especially in cerebral cortex, hippocampus and medulla oblongata. The data suggest that both iNOS and eNOS provide neuroprotective effects, helping to limit the extent of spontaneous apoptosis in brain of young-adult and aged mice. / Nitric oxide (NO) has either pro-apoptotic or anti-apoptotic effects on neuronal cells, depending on concentration of NO produced by different source of NO synthases (NOSs) including neuronal-NO-synthase (nNOS/NOS-1), inducible-NO-synthase (iNOS/NOS-2) or endothelial-NO-synthase (eNOS/NOS-3) and possibly age of the individual. The present study determines if genetic deletion of nNOS, iNOS or eNOS alters levels of aging-induced apoptosis in vivo and hydrogen peroxide (H2O2)-induced-apoptosis in organotypic brain slice cultures using NOS-knockout mice. The quantitative ultrasensitive techniques using capillary-electrophoresis with laser-induced-fluorescent detector (CE-LIF) and Cell-Death---Detection-ELISA were used as novel ways to accurately measure the levels of apoptotic-DNA-fragmentation. Expressions of different forms of NOSs were determined by immunohistochemical-staining. / Third study determined H2O2-induced apoptosis in hippocampal and cerebellar slices from young-adult (8-10 weeks) and aged (12-24 months) C57BL/6J control mice, as well as iNOS- and eNOS-knockout mice (determined by Cell-Death-Detection-ELISA measuring levels of apoptotic-DNA-fragmentation). The data show spontaneous onset of apoptosis occurred in both hippocampal and cerebellar slices during culturing, beginning at 24 hours and progressively increasing for 48--72 hours. Staurosporine (positive-control) and H2 O2 both caused time-dependent increases in apoptosis in both hippocampal and cerebellar slices, compared to time-matched controls. Lastly, genetic deletion of iNOS greatly reduced levels of spontaneous apoptosis in young hippocampus and aged cerebellum, suggesting iNOS had contributed to induction of spontaneous apoptosis. / Chow Wing Han Vivian. / "Dec 2005." / Advisers: Siew Boon Chew Cheng; Ray Ronald Fiscus. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6218. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 144-153). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.