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The purpose of this study was to investigate and compare the attitudes of secondary school principals and superintendents of public schools in the States of North Carolina and Ohio concerning their attitudes toward health education programs in their respective States. North Carolina and Ohio Departments of Instruction and Public Health endorsed the study. From a total of 2,039 incumbent High School Principals and Superintendents, a randomly selected sample of 1,057 were sent a pre-tested research instrument containing fifty attitudinal statements. The reliability co-efficient for the instrument was .99. A 63 per cent return of usable responses was received. Responses to each of the fifty statements were statistically analyzed and the following significant differences in attitudes toward school health programs reported: eight significant differences between North Carolina Superintendents and Principals, seventeen significant differences between Ohio Superintendents and Principals, seventeen significant differences between North Carolina and Ohio Principals, and six significant differences between North Carolina and Ohio Superintendents. Conclusions related to each of the fifty statements included the magnitude of the difference and the direction of the difference. Recommendations were: that health education should be taught as a separate subject, that teachers need more and better training, that up-todate guidelines for over-all state programs should be published, that school administrators need frequent refresher courses, and that certification for health education should be distinct and separate from other subject areas.

Conventional cancer therapies can have severe side effects, so new strategies to limit these needs to be investigated. Several anticancer agents induce the expression of tumour suppressor gene p21 in colorectal cancer cell line HT-29. Interestingly, the stress protein HSPA1A is also often elevated in tumour cells and has an anti - apoptotic activity. The main aim of this study was to examine whether a two - pronged approach, overexpressing p21 (using genetic approach and inhibition of HSPA1A using pifithrin - µ would be effective in inducing apoptosis in tumour cells. Chitosan or BSA based delivery systems were evaluated for cytotoxicity, with the intension of using it for plasmid DNA based cell transfections in this study. The interaction of HSPA1A protein in combination treatments involving UV radiation and hyperthermia at 42℃ were also evaluated to perceive the various roles of HSPA1A in arresting colorectal cancer cells. Colorectal cancer cell lines HT-29 and leukaemia cancer cell lines U937 were used in the study. All experiments were performed with cancer cell lines maintained in culture medium devoid of antibiotics. Cell cytotoxicity were evaluated using MTS and PI assays. The rate of apoptosis was determined using annexin V and PI staining by flow cytometry. Chitosan or BSA based microparticles or microgels were observed for size determination or morphology using scanning electron microscopy. Full length human p21 inserted plasmid DNA was a gift from Mien - Chie Hung, Addgene, USA. HT- 29 cells were subjected to p21 plasmid DNA transfection effects. Cells were treated with pifithrin - µ (15µM) prior to gene transfection to address its combined effect with p21 plasmid DNA transfection. HSPA1A and p21 protein expression studies were analysed using FITC labelled antibodies by flow cytometer. Combination studies with HSPA1A inhibitor pifithrin - µ and UV reflected enhanced cytotoxicity compared with either of the treatments independently. Hyperthermia at 42℃ induced apoptosis by MTS assay, which was confirmed by flow cytometric analysis in both the cell lines tested. Considering the cytotoxicity reflected by the chitosan or BSA delivery systems in drug free states, the p21 plasmid DNA transfection was carried out using lipofectamine 2000. Both overexpression of p21 and inhibition of HSPA1A protein with pifithrin - µ enhanced the rate of apoptosis with statistical significance of (p-< 0.0001****) compared to the respected controls. The data in this thesis suggests the inhibition of HSPA1A in combination with increased p21 would be a promising therapeutic strategy for the treatment of colorectal cancers.

In recent years, compelling evidence has accumulated suggesting heat shock proteins (HSPs) which are generally believed to be localised and functioning mainly within eukaryotic cells as cyto-protective molecular chaperones, are also localised in the extracellular milieu. Depending on their localisation, on the cell surface (membrance-bound or embedded), or in the peripheral circulation, extracellular HSPs may induce apoptotic cell death, or in contrast protect cells from cell damage and/or cell death when exposed to cellular stress, or may even elicit a stimulatory effect on the innate immune response including cell activiation and cytokine secretion. Hence, the localisation of intracellular and extracellular HSPs appears to be critical in determining their roles in terms of stimulating cell death, cyto-protection, or immune activiation under normal physiological conditions and following exposure to stress stimuli. This thesis describes the intracellular expression, up-regulation, and cell surface localisation of endogenous HSPs: HSP27, Hsp60, Hsp72 and Hsp90 by flow cytometry, florescence microscopy and Western blotting, under control conditions and in response to environmental stress using in vitro and ex vivo models with the intention of determining their physiological roles. The ability of extracellularly administered HSPs (Hsp70 and Hsp72) to protect cultured U937 cells in vitro or peripheral primary human leukogytes or erythrocytes ex vivo from various stress stimuli was demonstrated and was found to be dependent on surface binding and/or internalisation via scavenger receptors (SRs) or phosphatidylserine (PS), which could be blocked by receptor specific ligands. Extracellular HSPs were also shown to be able to stimulate an immune response through the induction of U937 monocyte differentiation into macrophages as evidenced through the up-regulation of the surface receptors: CD36, SR-A1 and CD91 analysed by flow cytometry. These proteins were able to stimulate TNF-x and IL-10 production and secretion by U937 macrophages, shown by ELISA, and chemotatic properties were demonstrated using Boyden chambers. The cyto-protective and immune regulatory effects of extracellular HSPs have potential therapeutic value as treatments in a wide variety of clinical situations.

The body initiates an immune response to danger signals. The Danger model of the immune system postulates that danger signals are produced by exogenous molecules from foreign invaders, such as bacteria, and endogenous molecules released from damaged or injured cells. The response involves antigen recognition leading to up-regulation of cytokines and cell surface markers, followed by the recruitment of antigen presenting cells and T-helper cells which determine how the immune system responds. Endogenous danger signals include Hsp72 and HMGB-1. This thesis describes the development of specific antibodies and ELISAs for use in the quantification and detection of intra-cellular Hsp72 from cell extracts, and released Hsp72 from cell cultures which enabled the confirmation of physiological levels of Hsp72 from model systems. The ability of endogenous Hsp72 to stimulate an immune response was demonstrated and this response was not solely due to LPS contamination of recombinant protein preparations. Hsp72 was able to augment the response to LPS. In the presence of another endogenous danger signal, HMGB-1, relative amounts of Hsp72 were shown to augment a pro-inflammatory response whilst being able to maintain an anti-inflammatory response demonstrating Hsp72 has the ability to modulate the immune response. Hsp72 was also shown to be able to stimulate an immune response by binding to cell surface receptors, which could be blocked by specific peptides corresponding to known receptors. These include some receptors not utilised by LPS. The proportion of these different danger signals has consequences for the progression and outcome of an immune response and this may well be modulated by imposition of a supplemental or future stress at different points. In the most severe case, this can lead to death through sepsis following trauma.

Evidence suggesting that Hsp72 is actively participating in cellular signalling as well interacting with immune system dynamics has been increasing. This is true in healthy, stressed and diseased cells but to different degrees. Modulation of the plasma membrane association and secretion in the extracellular environment by different types of stressors is the key event that leads to different degrees of immune system activation. Hence a better understanding of the mechanisms of Hsp72 secretion and association with plasma membrane is crucial. This thesis investigated the tissue source and mechanism of Hsp72 surface presentation to plasma membrane structures and release in relation with different cellular and physiological stressors. In vivo models confirmed that different tissue types determine specific Hsp72 responses following the same stress and increase serum Hsp72 dependant on intensity and duration of the stress. Diseases models confirm that Hsp72 responses in specific cell populations is related to disease progression, while in vitro models clearly showed that there are multiple mechanisms of secretion and surface presentation, dependent on the nature of the stressor as well as the intensity and duration. This observations clearly change the view of extracellular Hsp72 as a danger signal and lead to a revision of the original danger model. It also suggests that manipulation of Hsp72 translocation through the different pathways involved may prove effective therapeutically.

Although a number of HSPs have been shown to be up-regulated in a wide range of human cancers, the full significance of this remains to be determined. The localisation of HSPs seems to be critical in determining their role in cancer cell survival; High intracellular levels (iHsp) appear to be advantageous to the tumour cell, inhibiting key steps in apoptosis, while in some circumstances, surface expression (sHsp) appears to be detrimental to the cell, aiding immune recognition by various effector cells. Consequently, clarifying the importance of HSP cellular location in the cancer setting may lead to the development of novel therapies based upon manipulation of HSP localisation. This thesis had two major aims; (1) to investigate the cellular localisation of HSPs in leukocytes from patients with both myelocytic and lymphocytic malignancies in order to establish relationships between apoptosis and stage of disease (2) to study the synergistic effect of four chemotherapeutic drugs with membrane fluidising agents, compounds which have the potential to modulate HSP localisation. Hsp90 and Hsp27 expression was shown to be restricted to the inside of peripheral blood leukocytes, while Hsp72 was localised both intracellularly and on the cell surface. In CLL, iHsp90 and iHsp27 levels were found to be significantly higher than in control subjects, while surface and intracellular Hsp72 was shown to be expressed either at very high levels or at very low levels. Furthermore, iHsp90 levels were found to be associated with stage of disease, while iHsp27 levels were shown to negatively correlate with levels of apoptosis. CLL patients with stable disease were found to express higher levels of iHsp72 than patients with progressive disease. However, in AML and MDS, levels of all HSPs in peripheral blood were found to be similar to those seen in control subjects, but disease patients showed a much wider range of expression. In AML, levels of sHsp72 positively correlated in all cell types, an observation not made in MDS patients or control subjects. HSP localisation was shown to be affected by membrane fluidising agents, with a movement of Hsp72 and Hsp60 to the cell surface. This effect was not due to proteotoxicity and supports data implicating the cell membrane in the regulation of HSP responses. This manipulation of HSP localisation and the increase in membrane fluidity resulted in increased sensitivity of CLL cells to three chemotherapeutic agents and points to the possibility that manipulation of membrane fluidity, may have significant value in the development of new treatment regimes.

Oxidative stress has been associated with a wide range of diseases, including cardiovascular diseases, Alzheimer's disease, atherosclerosis, Parkinson's disease and cancer. It also plays a role in the ageing process. Hyperhomocysteimia is commonly found to be associated with these diseases. The hyperhomocysteimia is a result of a deficiency in both folate and cobalamin Folate is known to reduce Hey and protect cells from apoptosis, but there are no studies investigating the impact of cobalamin on apoptosis induced by oxidative stress or the mechanism(s) of the protection. The aims of the research are to investigate the protective role of cobalamin and the possible mechanism(s) for this protection. It also examines the protective role of novel cobalamin and investigates their superior protection. The methods used in this research for apoptosis detection we used caspase-3 and the annexin-V, while for necrosis we used PI staining, where cell viability were detected using MTS assay. We also measured the generation of superoxide by Lucigenin-enhanced chemiluminescence and reactive oxygene species by using the redox active prob DCFH-DA. Moreover, the intracellular proteins were measured via staining with specific fluorescent-conjugated antibodies were detected using flowcytometry. Our result demonstrated that 25|iM of cobalamin protects cells from apoptosis. The protection by cobalamin was associated with induction of iHsp72 and iHO-1, and these are shown to be essential for the protection. Furthermore, our research demonstrated a novel mechanism of cobalamin-apoptosis protection involving induction of NfkB, ERK1/2 and AKT signal transduction pathways. In order to protect cells from apoptosis induced by oxidative stress, cobalamin induces the pNfkB which in turn regulate the iNOS and HO-1 induction. Cobalamin also induces thepERK1/2 which regulates the induction of Hps72 and Nrf2. And finally, pAKT induced by cobalamin which regulate the Nrf2 and HO-1 induction. The inhibition of any of theses pathways leads to loss the protection. The GSCbl and NACCbl provide a superior protection against oxidative stress, this protection involved induction of the signal transduction pathways and Hsps. To conclude; cobalamin provides protection against cells death induced by oxidative stress. Cobalamin achieves this by multiple pathways which include direct antioxidant stimulation and induction of signal transduction pathways. Different cobalamin derivatives have superior protections. These finding are a useful pharmaceutical tool in the treatment of the oxidative stress related diseases.

Bone remodelling is a complex process, which involves the coupling of bone formation to completed foci of bone resorption, the balance between these 2 processes determines if bone is lost or gained at a particular site. During bone resorption osteoclasts release growth factors sequestered in bone matrix, which are thought to initiate new bone formation. On the other hand, osteoblasts can regulate osteoclast activity through the expression of the counter-acting cytokines, RANKL and OPG. The aim of this project was to determine if factors released during bone resorption impact on the RANKL/OPG system or on osteoclasts directly to regulate bone remodelling. OPG secretion was characterized in a number of osteoblast-like cells and the osteosarcoma cell line MG-63 was chosen as a model for osteoblastic cell behaviour in vitro. EDTA bone extracts prepared from normal human cortical bone powder were used to treat MG-63 cells in vitro. The response to the extract was dependent on the purification procedure used. OPG production was inhibited by partially purified extracts prepared using hydrophobic interaction chromatography, C18 SPE. In comparison extracts prepared using size exclusion centrifugal filters stimulated OPG secretion in confluent MG-63 cells. Therefore bone matrix constituents were able to influence osteoclast activity directly and indirectly through the osteoblastic cells to produce the same response. The simplest mechanism for this co-ordinated response would be the presence of one factor in the extract that is able to influence both osteoblasts and osteoclasts. The identity of the factor responsible for the opposing effects seen in the bone matrix extracts is at the moment unknown. The work presented in this thesis clearly demonstrated that unknown growth factors present in bone matrix influence bone remodelling.

Heat shock proteins (Hsps) are increasingly being seen as having roles other than those of intracellular molecular chaperones, particularly with regard to their potential to act as cytokines, and to stimulate the innate immune system. Hsps have also been found to promote bone resorption and osteoclast formation in vitro, although the mechanism has not been previously identified. The overall aims of this thesis were to determine whether Hsps could stimulate bone resorption by affecting the RANKL/OPG pathway, and to address the hypothesis that Hsps can act as a danger signal to the innate immune system. In order for Hsps to affect either the RANKL/OPG system of bone resorption or act as danger signals they would need to be actively released from cells, ideally in a controlled manner following exposure to the source of stress. Hsp60 and Hsp70 were found to be released from a range of immune cells including the cell lines Jurkat and U937, and also PBMCs, T-cells and B-cells. This release was not due to cell damage. The release of Hsp60 and Hsp70 were downregulated by inhibitors of protein secretion, in particular Hsp70 release was reduced by compounds that inhibited lysosomal pathways and Hsp60 release by classical secretion inhibitors. Hsp60, Hsp70, GroEL and LPS all affected the RANKL/OPG system of bone regulation; OPG production and release was down-regulated in the MG63 and GCT osteoblast-like cell lines following treatment with Hsp60, Hsp70 and LPS, and RANKL expression was upregulated following treatment with Hsp60, Hsp70, GroEL and LPS. This effect on the RANKL/OPG system was found to translate into an effect on osteoclast formation when conditioned media from treated osteoblasts was added to osteoclast precursors in the presence of M-CSF. A range of different factors that affected Hsp release were identified; PHA activation of PBMCs was found to upregulate Hsp60 release from PBMCs. GroEL and LPS caused an upregulation in Hsp70 release from PBMCs and GCT osteoblast like cells, and Hsp70 was found to stimulate Hsp60 release from PBMCs and GCT cells. These responses of Hsp release were used to form a theory of a cascade-like danger signal that may occur when cells are exposed to bacterial infection and which would result in activation of antigen presenting cells via previously identified receptors for Hsps such as CD14/TLR4 or by unidentified pathways. The elevated release of Hsps in response to GroEL and LPS was also identified as a mechanism that could stimulate bone loss during infection or autoimmuniry by affecting the RANKL/OPG system. hi conclusion, Hsp60 and Hsp70 can be released from immune cells under normal conditions, and from both immune and osteoblast-like cells following stimulation with LPS and other Hsps. The observed release responses provide a mechanism through which Hsps can act as danger signals to the innate immune system, and also as promoters of bone resorption via the RANKL/OPG system.

Osteoarthritis (OA) is a common musculoskeletal disability and represents a major health burden to society. Pathological changes are found in all tissues of the joint; however studies on bone are few. The aims of this thesis were to characterize some of the densitometric, mechanical and compositional properties of cancellous bone from the Superior (Sup) and Inferior (Inf) regions of human femoral heads, and to compare age-selected healthy bones with those from patients with end-stage OA. From coronal sections of the femoral head, bone cores were drilled out along the anterior-posterior axis and non-adherent fatty tissues removed. Measurements of apparent (PA), true (pj) and volumetric bone mineral density (BMDv) were made prior to determining the ultrasound-derived elastic modulus (Eu) and the compression-derived parameters, compressive modulus (Ec), yield strength (CTY) and yield energy (Wy). From aliquots of powdered bone, calcium and hydroxyproline were determined and a minerahcollagen ratio calculated, and osteocalcin, IGF-I, IGF-II and IGFBP-5 measured by RIA. Another aliquot was processed to remove soft tissue, demineralized in EDTA and the resulting collagen matrix digested with trypsin. From these crude tryptic digests (CTDs), divalently and trivalently (ICTP, IIINTP) crosslinked collagen telopeptides and procollagen propeptides of collagens type I and III were analysed by RIA. PA, BMDv, EC, ay, Wy and EU were systematically increased in cores from the Sup region of both Normal and OA groups (all/KO.05) and reflects differences in loading experienced by this region. In OA bone, PA, BMDv and EU were increased in the Inf region (all/KO.05) possibly as a result of adaptation of the bone to altered loading patterns at the hip. Furthermore, the relationship between EC and PA was different to those in Normals (p=0.019) indicating that other factors, such as architecture, may influence the stiffness of cancellous bone. Of the compositional measures, IGFBP-5 was systematically increased in both regions of OA bone (all /?<0.005) and may be the factor responsible for maintenance of bone mass in OA. The minerahcollagen ratio was decreased in the OA Sup region (p=0.008) indicating undermineralization of bone. In the mineralized matrix of OA bone, concentrations of ICTP:collagencTD and type III collagen antigens were increased in both Sup and Inf regions (all/><0.05) suggesting an increase in type I collagen trivalent crosslinking at the Qtelopeptide and an overall increase in type III collagen respectively. Of the relationships between the various properties, inverse correlations were found between mineral.'collagen and ICTPrcollagenciD ratios (rs= -0.36,/?<0.05) in the OA group indicating increased trivalent collagen crosslinking when bone is under mineralized. In the Normal group PA correlated inversely with IGFBP-5 (rs=-0.64 and -0.72, bothp<0.05) and OC (rs=-0.59,/7=0.056 and -0.71, p<0.05) at both Sup and Inf regions respectively, but were lost in the OA group suggesting loss of regulation at this level in OA. hi conclusion, the cancellous bone in OA femoral heads is denser, but not stiffer than that of Normal bone, and has an altered composition with respect to both structural (ICTP) and regulatory (IGFBP-5) factors which may affect the quality of the bone matrix.