In the extreme environment of space, radiation induced health issues is a major concern. The ability to induce higher levels of free radicals and reactive oxidative species (ROS) are factors to be addressed. Ceria nanoparticles (CNPs) can provide a means to scavenge ROS through regenerative redox coupling that occurs on the surface and acts as a radioprotectant. Additionally, the defect levels in CNP can be categorized by the Ce3+/Ce4+ ratio with a high ratio indicating superoxide scavenging, a radical species with high oxidative potential. However, engineering a specialized Ce3+ NP often requires a harsh reducing agent. We hypothesized a wet-chemical synthesis utilizing both reducing and non-reducing sugars to engineer stable CNPs with high Ce3+ state. This sustainable process uses simple sugars to ensure high biocompatibility while maintaining the specific vacancy density found in Ce3+ dominant CNP. X-Ray photoelectron spectroscopy (XPS) show that the reducing sugars allows for nearly 70/30 Ce3+/Ce4+ ratio compared to non-reducing sugars. This high Ce3+/Ce4+ ratio of CNPs can be useful in scavenging ROS in space radiation applications. In addition, typical drug molecules utilize biopolymers which can increase ROS under the ionizing radiation environments found in space. To improve the drug viability, we hypothesized CNPs conjugated to drugs as a viable solution. Current results indicate high Ce3+ structural confirmation of ceria nanoparticles using a wet-chemical synthesis. The synthesized nanoparticles were then conjugated with risedronate, a third-generation bisphosphonate. Microwave radiation studies indicated that CNP was able to be used as a radioprotectant as it prevented changes in drug chemistry as detected by UV/Vis spectra after exposure to microwave radiation. Finally, in vitro human mesenchymal stem cell results from alkaline phosphatase (ALP) and Alizarin red S (ARS) assays, suggest potential for the conjugates to differentiate cells. The mechanism for radioprotective ability can be attributed to the high Ce3+ state.

Racial/ethnic disparities persist in hypertension (HTN) prevalence in the United States, and African Americans are disproportionately affected. The incidence is more than two-folds in African Americans compared to Caucasians, and mortality is highest among African Americans. Understanding the risk factors in HTN and how these factors vary across racial/ethnic groups is essential to reducing the mortality among African Americans. This study examined the prevalence of HTN among a sample non-institutionalized U.S. residents (N = 30,852), assessed racial/ethnic disparities and determined factors associated with racial/ethnic variance in HTN. A cross-sectional design was used to address these aims, utilizing the National Health Interview Survey, 2003 dataset. Chi square and logistic regression techniques were employed in the data analyses. The race-nonspecific prevalence of HTN was 26.7% (N = 8,243). African Americans had the highest prevalence (35.5%), Caucasians (27.5%), and Hispanics (18.6%), p < 0.01. African Americans were 45% more likely to be hypertensive relative to Caucasians, Odds Ratio (OR) = 1.45, 99% Confidence Interval (CI), 1.16-1.82. African Americans significantly differed from Caucasians in the factors that were associated with HTN: smoking, alcohol, physical activities, age, higher income, college education, body mass index, marital status, higher cholesterol and diabetes mellitus. After controlling for these factors, ethnic/racial disparities in HTN persisted. Compared to Caucasian, African Americans had a 61% increased in HTN prevalence, (OR = 1.61, 99% CI, 1.39-1.86) and Hispanics had a 27% decreased prevalence, (OR = 0.73, 99% CI, 0.68-0.79). Confirming that HTN differed by race/ethnicity while controlling for associated factors, this study contributes to positive social change by highlighting the importance of biologic or biologic-environmental interactions for future research or intervention planning.

Prevalence of onychomycosis, as high as 26.9% in the general population, can be reduced by improving current antifungal treatment. This could be accomplished by understanding prognostic factors, especially healthy nail growth, associated with achieving complete cure. This population-based study aimed to evaluate if healthy nail length or percentage of total full nail length as healthy can be early indictors for complete cure. Logistics regression analyses were performed by comparing variables between a population who achieved the complete cure and a population who failed after both populations received the same antifungal treatment in two large randomized double-blinded clinical trials that assessed drug efficacy. Results showed that the largest odds ratios for healthy nail length (mm) and percent of total nail grown as healthy (%) were achieved at Week 12 with 1.63 and 1.07, respectively. Mean healthy nail length at Week 12 was 3.56 mm among cured patients and 1.90 mm among failed patients. Other significant baseline factors for the cure were: younger in age; naive to antifungal treatment; and having less severe disease. Growth of healthy nail during the treatment period is significantly associated with achievement of complete cure. Treatment success might be improved by monitoring the healthy nail growth. This study bears public health importance and can foster positive social changes because better managed disease can improve patient's quality of life and reduce financial burdens to the healthcare system. It could also be a tool for researchers to filter out better drug candidates and reduce research costs therefore cheaper treatments.

The purpose of this study was to determine the contamination level of Campylobacterjejuni in chicken quarters. Ninety-seven thigh and breast samples were purchased from thee supermarkets (Publix, Winn- Dixie, and Sedano's) in Miami-Dade County, Florida over an eight-week period. The bacteria were removed from the chicken skin by shaking the sample in a sterile bag containing nutrient broth. This extract was enriched in thioglycollate broth and subcultured onto selective media, which were incubated for 48 hours under microaerophilic conditions. Suspected colonies that were positive for the four biochemical tests performed were considered C. jejuni. The overall rate of contamination was 62%. Publix had the highest rate of contamination, 72%. Winn-Dixie had a contamination rate of 66%. Sedano's had the lowest rate of contamination, 48%. These findings show that the current methods used in preparing chicken for retail sale is not sufficient to eliminate pathogens, including Campylobacter jejuni.

Experts suggest that the cultural competence of healthcare providers is a critical factor impacting healthcare services to the ethnically diverse patient populations in the U.S. and that it may play a role in improving outcomes and reducing health disparities; however, the association between cultural competence and health outcomes remains unclear. This study used a cross-sectional quantitative design grounded by cultural competency constructs and the ethnic origins theory to explore the relationships between provider cultural competence, adequacy of prenatal care, and neonatal health outcomes in Hmong women, a population whose cultural beliefs affect their use of early and adequate prenatal care. Patient perception and provider self-reported cultural competence data were collected from 80 patients and their 19 corresponding providers. No correlation was found between the patient and provider total cultural competency scores, nor were they predictive of adequacy of prenatal care or neonatal outcomes in multiple regression analyses. However, 3 specific constructs related to physicians' ability to communicate and demonstrate culturally competent behaviors predicted adequacy of prenatal care. There was a moderate but negative correlation between patient and provider cultural competence subscores and a significant difference in 6 of 13 survey questions suggesting discordance between patient and provider perceptions regarding communication during the healthcare encounter. Implications for positive social change include new prenatal care delivery models that incorporate Hmong health beliefs that may increase the number of Hmong women who receive adequate prenatal care, thus potentially improving birth outcomes. This can lead to reduced health disparities experienced by the Hmong.

Stigma surrounding HIV and AIDS poses a significant threat to the curtailing of the epidemic by acting as a barrier to HIV testing and disclosure of serostatus. Previous research in the United States found personal knowledge of someone with HIV/AIDS to be a predictor of lower levels of HIV/AIDS-related stigma. However, no study to date has examined this relationship in Zimbabweans. Allport's contact hypothesis was hypothesis was the theoretical frame used to assess the effect of direct contact on public attitudes towards people living with the human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) in Zimbabweans with the goal of identifying areas of stigma reduction. Stigma surrounding HIV and AIDS poses a significant threat to the curtailing of the epidemic by acting as a barrier to HIV testing and disclosure of serostatus. Previous research in the United States found personal knowledge of someone with HIV/AIDS to be a predictor of lower levels of HIV/AIDS-related stigma. However, no study to date has examined this relationship in Zimbabweans. This study surveyed English-speaking adult Zimbabweans from anywhere in the world. Descriptive statistics, Pearson product-moment correlation coefficients, and hierarchical stepwise multiple regression were used for analysis. Personal knowledge of someone with HIV/AIDS and the beliefs about HIV/AIDS transmission through casual contact emerged as the statistically significant predictors of stigma in the final model (r = -.172, p < .01, and r = .281, p < .001, respectively. There was an inverse correlation between personal knowledge of someone with HIV/AIDS and stigma. Potential positive social change contributions include a mobilized population with a common goal of eradicating HIV/AIDS, seeking HIV/AIDS testing services, disclosure of HIV serostatus, and seeking treatment leading to control of HIV transmission.

<p><strong>Background </strong>The possibility of ageing independently during the past 2 decades assumed a meaning which comprises different aspects. It has been recognized, in studies involving older adults but also by important Health Organizations (such as WHO), that disability could originate from different causes: physical limitations, external causes (such as personal assistance or building barriers), individual causes (lifestyle, behavior, positive attitude) and societal factors. Measuring the level of disability in a comprehensive way could help predict the amount of help and the best resources needed for older adults to cope with disability and remain independent as much as possible. The SAGE scale has been developed to be a complete and easy to use tool to measure independence in older adults.<strong></strong></p> <p><strong>Objectives </strong>The aim of this thesis is to describe the methodology and the design of a study and to assess the validity and reliability of the SAGE scale.<strong></strong></p> <p><strong>Design </strong>SAGE validation will be measured in a cross sectional study, involving 240 older adults conveniently sampled from 3 different facilities in the Hamilton area. Community dwelling older adults, patients recovering from a stroke and subjects living in a nursing home, will be assessed at one point in time with the new tool (the SAGE scale) together with four widely used scales to assess cognitive abilities (Montreal Cognitive Assessment), functional abilities (The Franchay Activity Index), the modified-Rankin scale and the CSHA Clinical Frailty Scale. This thesis will describe the processes through which assess the content, construct and criterion validity. The hierarchical sequence of items will also be investigated as well as specificity and sensitivity of the new tool. <strong></strong></p> <p><strong>Conclusion </strong>The development of the SAGE was motivated by the recent need for an instrument able to capture all the activities that are important for the elderly to be able to age with dignity and independence. The results of this study, if positive, will be useful for further investigation of the SAGE, as a screening tool to recognize and detect early loss of independence in this group of individuals.<strong></strong></p> / Master of Science (MSc)

<p>Multi-faceted interventions that include some form of a clinical information system have been shown to improve primary care physicians' management of chronic diseases. The objective of this pilot study was to assess the feasibility of a cluster randomized controlled trial of a multi-faceted intervention, which includes a clinical information system, to improve the management of the chronic disease of tobacco use by physicians. Feasibility was assessed with respect to the use of a measurement tool (Smoking Status Identification Card) and use of a new smoking cessation management module in the clinical information system.</p> <p>Letters of invitation were sent out to the 65 primary care physicians (in 38 primary care practices) who were subscribed to the web-based clinical information system (P-PROMPT CDMS). Five physicians from 5 primary care practices agree.d to participate, who were stratified and then randomized to the intervention (2 primary care practices) or control group (3 primary care practices).</p> <p>Following the 12-week study period, SSIC completion reached the 90% threshold success criterion in 2 of the 5 primary care practices (one each from the intervention and control group). The intervention group demonstrated basic use of the new smoking cessation management module that reached 21.9% and 19.0% in each of the respective practices, which was below the 30% threshold success criterion. A preliminary evaluation of physician delivery of smoking cessation counselling demonstrated a trend to a higher percentage of Ministry of Health and Long-Term Care (MOHLTC) physician service billing codes submitted among the physicians in the intervention group, which may be indicative of greater smoking cessation counselling.</p> <p>It is concluded that a randomized controlled trial to test a multi-faceted intervention is not feasible with the current study design. Significant modifications to the current study design are required that can potentially be tested prior to progression to a larger trial.</p> / Master of Science (MS)

<p>The purpose of this investigation was 1) to establish an optimal technique for isolating osteoprogenitor cells in vitro using human femoral cancellous bone as a donor site, and 2) to evaluate the effects of various factors on differentiation of osteoprogenitor cultures. Two isolation techniques evaluated were enzyme digestion and primary explant technique. Furthermore, bone morphogenetic protein 2 (BMP-2) and doxycycline were supplemented in a dose dependent manner into various osteoprogenitor cell containing culture dishes. To compare isolation techniques and the effect of supplemented factors, we isolated cell populations from cancellous bone of the femoral neck from 7 and 6 patients, respectively, with osteoarthritis undergoing total hip replacement surgery. Bone derived osteoblasts and their bone nodules were identified using Von Kossa stain. The cell yield of the two isolation techniques was quantified by hemocytometer counts. The ability of the cells to differentiate into bone forming osteoblasts was evaluated by comparing numbers of Von Kossa positive nodule counts. Using alkaline phosphatase (ALP) staining, ALP quantitative assay and osteocalcin polymerase chain reaction, our study is the first attempt to determine the effects of doxycycline, along with the more commonly used BMP-2, on the differentiation of osteoblasts into bone forming colonies.</p> / Master of Science (MS)

<p>Human atherosclerosis is a disease of the blood vessel wall caused by an interplay between inflammatory, thrombotic, and lipid factors. A contributing or causal role for infection in that inflammatory response was first proposed in the 19th century, and with the advent of more sophisticated diagnostic techniques, a new search for a microbiologic etiology of human atherosclerosis has been rekindled. In this thesis, I examine methods for investigating whether infections contribute to human atherosclerotic cardiovascular disease. I explore three different technologies: serology (measuring antibody), inflammatory markers (as risk markers and as surrogates for infections), and the direct measurement of bacterial or viral DNA in the bloodstream. I examine three different study designs: cross-sectional, case-control, and cohort. Chlamydia pneumoniae , an obligate intracellular bacterium, is the primary focus of these studies. In addition, cytomegalovirus and other infections are included as controls, with the a priori expectation that these other infections would not be related to cardiovascular disease. We found a relationship between cardiovascular disease and C. pneumoniae antibody status in a small case-control study, but found no independent association in a large, prospective study. Inflammatory markers were measured in the prospective study, and were associated with cardiovascular events, yet no clear association between inflammation and infection was found. However, in developing methods for directly detecting bacterial and viral DNA in the bloodstream, we found that serology itself was not associated with current detection of bacterial DNA. Furthermore, we found a strong relationship between C. pneumoniae and smoking, and conclude that future studies need to examine the interaction between infection, inflammation, and smoking status.</p> / Doctor of Philosophy (PhD)