Poor indoor air quality in schools is associated with diminished learning, health risks to students and staff, and economic costs. This dissertation reports findings from the Texas Elementary School Indoor Air Study (TESIAS). The objective of this investigation is to establish a baseline for indoor environmental parameters. The investigation selected 30 elementary schools from 2 school districts. One school district was located along the Texas/Mexico border in a hot-humid climate region. The other school district was located in central Texas in a mixed-humid climate region. Phase I of the study was a questionnaire completed by 1336 teachers and other school staff. Phase II of the study collected both qualitative and quantitative data in 120 classrooms including continuous monitoring of comfort parameters (carbon monoxide, carbon dioxide, temperature, and relative humidity). Phase III collected more in-depth quantitative data, including fungi and bacteria concentrations, in 12 classrooms. This dissertation investigates potential differences in the study data between school districts and between portable and traditional classrooms. The two major findings of this study concern water leakage from roofs and inadequate ventilation. Roof leaks were the highest reported source of water incursion and correlated with health symptoms. Free-standing small footprint classrooms had fewer roof and wall leaks than traditional classrooms. The simple low pitch roof design and sufficient overhangs typically found on the small footprint buildings studied likely result in less reported roof leaks. The measured carbon dioxide concentrations (both average and peak values) were well in excess of the recommended maximums and fewer than 15% of the classrooms met the recommended maximum concentrations. Relatively higher CO2 concentrations and relative humidity in the border school district were attributed to a greater frequency of blocked outdoor air intakes. Further investigation of novel HVAC systems, such as low velocity displacement ventilation, is needed. Ultimately, this study enables the development of best practices for school design for improved indoor air quality. / text

published_or_final_version / Public Health / Master / Master of Public Health

published_or_final_version / Nursing Studies / Master / Master of Philosophy

Objectives: Menthol is an organic compound synthesized or naturally obtained from peppermint or other mint oils and once added to cigarettes, is believed to have caused extra adverse health consequences (Kolawole S. Okuyemi 2004) compared with non-menthol cigarettes. This review has multi-purposes: First, to review and summarize the causes of African Americans’ high preference over menthol cigarettes; Second, to review smoking cessation studies and determine the association between menthol cigarettes and reduced quitting rates for African American smokers; Third, to gather information of evidence-based interventions for menthol cigarette smoking cessation. Methods: This article reviewed 16 journal articles through PubMed search using the following key words: menthol cigarette, smoking cessation, African American. And only one Chinese article was found by searching the key word “薄荷?” in CNKI Chinese database. Further search was done by using Google search engine and got 11 electronic articles or webpages for this topic. According to the objectives of this article, 3 journal papers were reviewed for examining the causes of African American smokers’ high preference over menthol cigarettes; 8 journal papers were reviewed for determining the association between menthol cigarettes and reduced quitting rates for African American smokers. In this section, the inclusion criteria include: age (18-65); gender (male, female); study design (cohort, cross-sectional, RCT). At last, 5 journal papers and 5 electronic resources including news were reviewed to gain an up-to-date insight for possible interventions of menthol cigarette smoking. Results: The leading causes for African American smokers’ high preference over menthol cigarettes include: like the minty/cool flavor; perceive menthol cigarette as having medicinal effects; menthol smokers’ influences from one’s social network; tobacco companies’ tailored marketing strategies. Overall, there were lower quitting rates for menthol cigarette smokers compared to non-menthol cigarette smokers at least among African American smokers. For menthol cigarettes and smoking cessation among African American smokers, 4 studies got significant results. For menthol cigarette and non-menthol cigarette smoking cessation among African American smokers: study 1 (TABLE 2), 6 weeks abstinence rate 28.3% vs. 41.5%, p=0.006; study 2 (TABLE 2), 4 weeks abstinence OR=0.32, 95% CI [0.16, 0.62], p<0.05, 6 months abstinence OR=0.48, 95% CI [0.25, 0.9], p<0.05; study 3 (TABLE 2), 6 months abstinence OR=0.23, 95% CI [0.17, 0.31], p<0.05. Study 4 (TABLE 2) compared African menthol cigarette smokers to Whites non-menthol cigarette smokers, OR=0.72, 95% CI [0.53, 0.97], p=0.031. For another 4 studies, they got non-significant results but still revealed such an association. Conclusions: Causes for African American smokers’ high preference over menthol cigarettes were identified as: tailored marketing strategies; physical properties of menthol cigarette (taste, smell); and demographic/social/psychological/cultural/attitudinal causes. There were significantly lower quitting rates for menthol cigarette smokers compared to non-menthol cigarette smokers at least among African American smokers. For menthol cigarette smoking cessation interventions, whether or not a ban on menthol would be implemented or not, comprehensive programs that include educational program, clinical menthol cigarette smoking cessation aids, taxation for price control, and smoke free and related regulations are needed. At last, China should learn experiences from the US regarding analysis of preference and possible clinical, educational, and policy interventions for menthol cigarette smoking cessation and prevention. / published_or_final_version / Medicine / Master / Master of Public Health

The advance of nanotechnology has made it possible that pure silver can be engineered into nano scale level with less than 100 nm in size. So far many studies have confirmed anti-bacterial and anti-inflammatory efficacy of silver nanoparticles (AgNPs). In our previous study we have revealed that AgNPs could promote wound healing through modulation of cytokines in a burn wound model in mice. Nonetheless, the exact effects mediated by AgNPs on various cell types in skin, including keratinocytes and fibroblasts, during wound healing still remain unknown. Therefore, in the present study we targeted a full-thickness excisional wound model in mice to explore the action and potential toxicity of AgNPs on keratinocytes and fibroblasts. Immunohistochemistry staining and molecular assay were conducted to explore AgNPs-induced re-epithelization and cell differentiation in both in vivo and in vitro studies. We next targeted the healed skin after AgNPs-mediated wound healing using tensile test to compare their mechanical function. Meanwhile, immunohistochemistry staining and quantitative assay were utilized to further investigate and compare collagen deposition, and scanning electron microscopy (SEM) was used to observe the morphology and distribution of collagen fibrils in healed skin. Moreover, AgNPs of different sizes and doses were studied to investigate the potential toxicity, their influence on cell migration, and extracellular matrix (ECM) production. Key results: 1. AgNPs could accelerate excisional wound healing in mouse skin when compared with other formats of silver. 2. AgNPs mediated differential cellular response in skin cells. They promoted proliferation and migration of keratinocytes in epidermal layer, through which the re-epithelization process during wound healing was enhanced; while proliferation of fibroblasts in dermal layer was inhibited and they were driven into the differentiation of myofibroblasts, through which wound contraction process was strengthened. 3. AgNPs could suppress the proliferation of human keloid fibroblasts and ECM production including collagen, fibronectin and heat shock protein, which would suggest that AgNPs had anti-fibrosis effect. 4. The AgNPs could stimulate the proliferation of epidermal progenitors and their differentiation into keratinocytes during wound healing. This biological event further contributed to the re-epithelization process. 5. AgNPs-mediated healed skin possessed comparable mechanical function, collagen deposition and fibril alignment to normal skin, which suggested AgNPs could modulate collagen production during skin wound healing. 6. The inhibitory effect on fibroblasts and cytotoxicity mediated by AgNPs showed a dose-dependent and size-dependent manner. In conclusion, AgNPs not only contribute to healing of infected skin wounds through antibacterial activity, but can also accelerate wound healing through mediating differential cellular responses in different skin cell types and modulate collagen production during wound healing. Furthermore, there should be an optimal concentration and size to exert maximal biological action with minimal toxicity for each specific cell type. Present studies further extended our knowledge of AgNPs and have implications for treatment of wounds in clinical setting. / published_or_final_version / Surgery / Doctoral / Doctor of Philosophy

Exposure to methyl mercury (MeHg) is a global concern. Increased chronic exposure to MeHg among fish and marine mammal consuming populations will increase the risk of prenatal exposure and as a result, the risk of infant brain damage and neurotoxcity. It is therefore important to understand the role of environmental factors, such as nutrition, in determining susceptibility to MeHg toxicity. Three nutrients (selenium (Se), vitamin C and vitamin E) were selected for examination of their interactions with the mechanisms of McHg cytotoxicity in vitro. Two hybrid neural cell lines (M03.13 and NSC-34) were evaluated for their usefulness in the study of MeHg cytotoxicity. Sixteen toxic endpoints were selected for investigation of growth, viability, structure and biochemistry. Both cell lines responded to MeHg exposure in a dose dependent manner for the majority of endpoints suggesting that both MO3.13 and NSC-34 cells undergo structural and biochemical changes during exposure to McHg, but that MO3.13 cells are more sensitive to DNA, mitochondria) membrane damage and glutathione (GSH) depletion and that NSC-34 cells are more sensitive to protein damage and apoptosis. Se exposure lessened the MeHg-induced decrease in DNA and GSH concentrations in both cell lines. In NSC-34 cells, Se also increased F-actin concentrations and prevented an increase in caspase-3 activity. Se may alter the mechanism of cell death by preventing McHg disruption of DNA replication thus maintaining the production and function of peptides (GSH) and protein (polymerized actin) that aid in MeHg detoxification and neural function. In NSC-34 cells, vitamin C prevented the induction of caspase-3 activity and lessened DNA damage and GSH depletion. Vitamin E lessened GSH depletion and lessened G-actin depletion. Both vitamin C and E improved GSH status, but vitamin C also delayed McHg damage of DNA and prevented early signs of apoptosis suggesting these two vitamins interfere with MeHg metabolism by diffe

Traditional male circumcision is a rite of passage among the AmaXhosa in South Africa. According to the custom of male traditional circumcision, initiates should remain in the bush for the entire seclusion period. The AmaXhosa male initiates encounter complications due to a ritual that has gone wrong. Common complications are penile sepsis, dehydration, penile amputations and septicaemia. As a last resort, when the AmaXhosa male initiates do not improve from complications associated with the custom they are referred to hospital for admission (Meintjes, 1998; Warren-Brown, 1998). The main purposes of this study were, first to explore and describe the delivery of care to the hospitalized AmaXhosa male initiates whilst in the hands of healthcare professionals and professional care system. Second, to describe what constitutes culturally appropriate care for hospitalized AmaXhosa male initiates. This study took place in three research sites, that included one rural hospital and two urban hospitals which admitted the AmaXhosa male initiates of traditional circumcision. A total of 13 hospitalized AmaXhosa male initiates and nine health professionals took part in this study. Leininger's ethnonursing qualitative research approach was used to guide this study. Data were collected, using purposive sampling, by means of unstructured interviews using guides, tape-recorder, and field notes. The study was first piloted at Umlamli Hospital using the same data collecting strategies as for the major study. Data from key and general informants were analysed separately using Leininger's (1991) four-phase method. This was carried out in order to answer the research questions and research purposes. Major themes and patterns emerged from this process. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2009.

Low-income communities are potentially more vulnerable to physical, social and environmental hazards than wealthier communities. The lack of services associated with these communities (such as water supply, sanitation facilities and electrification) has increased the exposure of households to health hazards. These households also lack the coping mechanisms and resources to deal with the stress that these hazards impose on them. This study is concerned with the potential health hazards imposed from indoor air pollution. Traditional health risk assessments are used to determine the level of risk to human health from a variety of chemical or biological hazards. What these assessments do not include however, is a measure of the vulnerability of the household. The aim of this study therefore, was to develop a methodology for generating a vulnerability index for the inclusion of factors underlying urban poverty and vulnerability into a risk assessment of indoor air pollution. The approach adopted in this study followed an iterative and inductive pathway. Theories on risk assessment and urban vulnerability were explored in order to understand the manner in which risk to human health is assessed and compounded by vulnerability. Secondary data sources as well as a household survey provided information that aided the selection of a number of vulnerability indicators. These indicators were chosen as measures of vulnerability specifically for low-income households in South African settlements. The findings of the research show that there are a number of factors or issues which underlie vulnerability. The issues are related to demographics, livelihoods, physical exposures, externalities, services and general health. This study used a four-tiered selection approach to sift through the issues of vulnerability and to transform the key issues into a set of vulnerability indicators which make up the vulnerability index. / Thesis (M.Sc.)-University of Natal, Durban, 2003.

Methylmercury (MeHg) is an environmental contaminant mainly present in fish and seafood. The long-term consumption of these fish and seafoods could pose a health risk to pregnant women and their children. Animal studies were conducted to assess the effects of MeHg exposure on reproduction and offspring development as well as the potential benefits of nutrient supplementation. Adult female rats were treated by gavage with MeHg at dose levels of 0.5, 1.0 or 2.0 mg/kg/day for 4 weeks prior to mating and throughout pregnancy, and then were allowed to deliver. In a second study, adult female rats were treated with MeHg at 1.25 mg/kg/day for the same duration, and they were fed diets containing an extra 1 ppm selenium (Se), or 225 IU/kg vitamin E, or both of these two nutrients, 4 weeks prior to MeHg dosing, and then throughout McHg treatment. (Abstract shortened by UMI.)

Thesis (MTech (Biomedical Technology))--Cape Technikon, 2000. / Professionals in a healthcare setting use latex gloves on a daily basis, primarily to prevent transmission of microbial and viral organisms to and from patients and specimens. Repeated exposure to latex proteins (through direct skin contact or mucous membrane absorption) leads to the formation of circulating latex-specific antibodies and increases the risk of sensitisation. Among all known risk groups, healthcare workers have the highest risk to develop latex hypersensitivity. Early detection of antibodies or predisposing factors (e.g. atopy or impaired skin barrier function), could assist in the identification and management of risk groups and limit possible sensitisation. An experimental group with high occupational latex exposure is compared to a control group with low or no occupational latex exposure at Tygerberg Hospital, Cape Town. A questionnaire was completed by all subjects to obtain a thorough history of past and present latex exposure and to identify other risk factors. A complete physical examination was done to evaluate clinical signs and symptoms of risk factors and latex hypersensitivity. Atopy was evaluated by means of the United Kingdom's Diagnostic Criteria for Atopy, personal and lor family history of atopy, haematogram and total serum IgE analyses. Latex-specific IgE antibodies were measured immunometrically. Skin prick tests were performed on subjects with negative in vitro results, but with predefined clinical symptoms suggestive of latex hypersensitivity. An