Thesis (Ph. D.)--University of Wisconsin, 1938. / Typescript (carbon copy). eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (p. [i]-iii).

A dissertation submitted to the Faculty of Health Sciences, University of the Witwatersrand, in fulfilment of the requirements for the degree of Master of Pharmacy Johannesburg. 2004 / As part of investigation of the biological activities of South African plant, a phytochemical and pharmacological investigation was carried out on five indigenous Vitex species; V. obovata ssp. obovata, V.obovata ssp. wilmsii, V. pooara, V. rehmannii and V. zeyheri . The chemical composition of the essential oils was determined using gas chromatography and mass spectrometry, and 1.8-cineole, a- copaene , caryophyllene oxide and y-muurolene were found to be the most abundant constituents in the essential oils of both V. obovatassp. obovataand V. obovata sssp. wilmsii. / IT2018

Tse Lap-Ah. / "July 2003." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2003. / 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 Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Para dar respuesta a la pregunta ¿Cómo es la historia natural de la silicosis en una población de trabajadores mineros de Perú?, se aplicó el análisis de supervivencia de Kaplan – Meier a la data de 4056 mineros peruanos que laboraron entre 1955 y 2006, y que buscaron voluntariamente asistencia médica entre los años 2003 y 2006. Se encontró casos de Silicosis aguda, acelerada y crónica, que progresa rápidamente una vez instalada -Toma 4.7 años pasar de Silicosis 0 a Silicosis III - disminuyendo la esperanza de vida en todos los casos. El periodo de latencia desde el inicio de la exposición laboral hasta el diagnostico de Silicosis 0 fue de 20.11 años, pero para trabajadores mineros de subsuelo este periodo de latencia fue de 13.45 años, y para trabajadores de minería de superficie fue de 21.07 años. La probabilidad de sobrevivir sin diagnostico de silicosis los primeros 5 años de vida laboral fue de 0.9871 +/- 0.004. La mediana de supervivencia global al diagnostico de silicosis fue de 25.7 años. La probabilidad de sobrevivir sin diagnostico de silicosis luego de 50 años de exposición laboral, aun cuando la exposición haya cesado fue de cero. Se demostró que en la historia natural de la silicosis influyen factores como edad, número de empresas en que laboró el huésped, área de superficie corporal, peso, índice de masa corporal, presión arterial, tipo de minería donde laboró el huésped (superficie, subsuelo).

A thesis submitted to the Faculty of Health Sciences, University of the Witwatersrand, in fulfilment of the requirements for the degree of Doctor of Philosophy / Background Silicosis rates in gold miners in South Africa are very high but there have been no analyses of long term trends. While much research has been conducted on occupational respiratory disease in gold, asbestos and coal miners, little is known about the respiratory health of miners of other commodities, such as diamonds and platinum, two of the most important minerals in South Africa. The ore bodies from which minerals are mined often contain other „incidental‟ minerals and compounds that may cause disease. Aims The aims of this thesis were to conduct the first ever analysis of silicosis trends in black and white gold miners over a 33-year period; to discuss the role of oscillating migration in the high rates of silicosis; and to explore the potential for workers in the diamond and platinum mining sectors to develop occupational respiratory diseases. Methods Gold, diamond and platinum mine workers were identified from the PATHAUT autopsy database at the National Institute for Occupational Health. Trends in silicosis from 1975 to 2007 were calculated separately for black and white gold miners because of differences in exposure, patterns of employment and autopsy referral patterns. The role of oscillating migration in the silicosis epidemic was explored. Diamond mine workers with asbestos-related diseases at autopsy and platinum mine workers with silicosis and/or fibrotic nodules in the lymph nodes were identified. Supplementary data from other sources were reviewed to viii exclude all those who might have been exposed to asbestos or silica, respectively, outside of the mining sector in which they worked. Asbestos lung burdens were calculated for the case series of diamond miners and mine tailings and soil samples were examined for asbestos fibres, using scanning electron microscopy. Findings The proportion of white miners with silicosis increased by 17% (from 18% to 22%) over the 33-year study period. That of black miners increased 10-fold (from 3% to 32%), primarily due to the aging workforce and increasing periods of employment. Adjusted odds ratios for silicosis increased with year of autopsy for black miners. Oscillating migration has also played a major role in the silicosis epidemic. Evidence indicates that diamond mine workers are at risk for developing asbestosrelated diseases and that platinum mine workers are at risk for developing silicosis. Conclusion The gold mines have failed to control silica dust levels adequately and prevent disease in mine workers. The sparsity of available dust measurements and poorly documented work histories are major obstacles to conducting occupational health research in South Africa; attention and legislation needs to be focused urgently on these areas. The PATHAUT database is the only occupational respiratory disease database in South Africa that can be used for disease surveillance, trend analyses and research in all mining sectors.

MSc (Med) Molecular Medicine and Haematology, Faculty of Health Sciences, University of the Witwatersrand, 2009 / This is the third phase of a project to identify, confirm, and operationalise biomarkers for crystalline silica dust exposure that could be used for surveillance of dust exposure levels in South African mines. The first phase of the project involved a comprehensive review of the relevant literature [Gulumian et al., 2006] from which ten potential biomarkers of effect were identified as being worthy of further investigation. The second phase of the project examined the ten identified biomarkers in silica dust-exposed and unexposed black male subjects [Murray et al., 2006]. Two of the ten short listed biomarkers, namely erythrocyte glutathione peroxidase (GPx) and serum Clara cell protein 16 (CC16), were found to have significantly reduced levels in the silica dust-exposed versus unexposed subjects. In addition, the biomarkers were found to be unaffected by HIV sero-status, smoking, age and the presence of silicosis. As a result, this third phase of the project aimed to confirm the levels of and further analyze GPx and CC16 in miners exposed to crystalline silica dust. This third phase involved the measurement of the levels of erythrocyte GPx and serum CC16 in 80 adult male gold miners upon their return from leave and then again two to six months after they had returned to work (involving exposure to crystalline silica). Before the field work was conducted, however, the optimal operational parameters for the biomarkers (namely storage temperature, delay in time between blood collection and separation, laboratory temperature and storage duration) were established. The results of these optimization experiments were used to develop Standard Operating Procedures (SOPs) for biomarker specimen handling and storage under field conditions, and for laboratory assays. In this phase, the findings of the second phase were confirmed in that the levels of GPx and CC16 were lowered in miners exposed to crystalline silica dust and were unaffected by age, race and cigarette smoking. In addition, while CC16 was unaffected by the presence of radiological silicosis, GPx may have been affected. Finally, the decrease in the levels of GPx activity and CC16 concentration observed in the study were unaffected by the level of silica dust exposure (high or low) as determined by job category or by the duration of crystalline silica exposure. Regarding the levels of GPx activity, the results suggested that GPx levels decrease after two to six months of chronic exposure to crystalline silica dust and remain decreased (throughout the working week and over a weekend) and then increase or even recover to normal levels during a period of leave. It was therefore concluded that GPx activity levels rise and fall, in response to silica dust exposure, gradually and over periods of some time, possibly months. The CC16 results were, however, less promising. After two to six months of chronic exposure to crystalline silica dust there was a significant change in CC16 on a Wednesday afternoon following an 8-hour shift and during the duration of a shift. In addition, there is the possibility that the observed changes were due to a time-dependent diurnal variation in the CC16 levels. It was concluded that the results of the current phase warrant further research into the use of erythrocyte GPx and serum CC16 as biomarkers of early effect from crystalline silica exposure.

A silicose em cavadores de poÃos da RegiÃo da lbiapaba à uma entidade nosolÃgica ocupacional adquirida por homens com idade mÃdia de 39 anos, cujas razÃes para cavar poÃos de modo artesanal sÃo: 1) ausÃncia de fontes naturais de Ãgua na RI; 2) existÃncia de longos perÃodos de estiagem; 3) falta de distribuiÃÃo democrÃtica da Ãgua existente no reservatÃrio da RI; 4) falta de alternativa de ocupaÃÃo para o ganho por parte desses homens; 5) estÃmulo à escavaÃÃo manual de poÃos pelas frentes de serviÃo dos planos emergenciais de combate aos efeitos da seca. Os cavadores acometidos adoecem em menos de 10 anos de exposiÃÃo à poeira podendo vir a adoecer em apenas 391,4 dias de atividade. Para prevenir a silicose, foi aplicada à populaÃÃo de 687 cavadores de cinco municÃpios da RI uma intervenÃÃo educativa primÃria conforme o mÃtodo Paulo Freire, para o aprendizado sobre o que à a doenÃa, como e por que os cavadores de poÃos a contraem e como podem evitÃ-la. O conteÃdo educativo do programa foi criado e repassado com a participaÃÃo ativa dos educandos, tendo sido feito de pessoa a pessoa, pelos profissionais de saÃde e cavadores; atravÃs de reuniÃo de grupo e da comunicaÃÃo de massa. No presente estudo, 283 cavadores dos 687 beneficiados com a intervenÃÃo responderam a um questionÃrio para se conhecer o papel dessa intervenÃÃo no conhecimento dos cavadores sobre a silicose e na atividade de cavar. Cento e quinze (40,6%) eram silicÃticos, 122 (43,1%) eram nÃo silicÃticos e 46 (16,3%) nÃo sabiam do seu diagnÃstico. Os resultados obtidos indicaram que as medidas educativas aplicadas aos cavadores de poÃos tiveram importante papel no controle da doenÃa. A maioria dos cavadores, 277 (98,9%), acredita que a atividade de cavar poÃos trÃs doenÃa. NÃo houve relaÃÃo entre a crenÃa e o estado de saÃde dos cavadores, (p= 0,362). Duzentos e setenta e um cavadores (95,8%) aprenderam que à o pà da pedra o causador da silicose e 221 (78,1%) disseram que se adquire a doenÃa cavando poÃos. Com relaÃÃo à melhor maneira de aprender sobre a silicose, os cavadores disseram que foi atravÃs de intervenÃÃo feita de pessoa a pessoa. A imensa maioria dos cavadores 241 (85,8%) interrompeu a atividade de cavar e o fato de serem silicÃticos influenciou de modo significativo a interrupÃÃo da atividade (p=0,001). O principal motivo para interromperem a atividade de cavar foi a silicose 211 (89,1%). A relaÃÃo entre o motivo para parar de cavar e o fato de serem portadores de silicose foi significativa: p=0,034. Entretanto, o desejo de mudar de atividade foi expresso pela maioria 174 (77,7%) e nÃo sofreu influÃncia do estado de saÃde dos cavadores, (p=0,831). A minoria que nÃo assimilou o conteÃdo educativo sobre a silicose ou que nÃo mudou de atitude quanto à atividade de cavar poÃos, nÃo se conscientizou da realidade e precisa receber atenÃÃes no sentido de alcanÃarem essa conscientizaÃÃo. / Silicosis affects pit diggers in the lbiapaba Mountain Range (IMR). They are men with a mean age of 39. The circumstances that favors the pit digging activities are: 1) lack of natural water sources in the IMR 2) long periods of drought 3) lack of water supply to the population from the local water reservoir 4) lack of alternatives jobs for those men 5) governmental measures with incentives in emergency programs which encourage the manual pit digging activities in an attempt to curb the drought effects. The pit diggers who acquired silicosis had less than 10 years of silica exposure. Most of them became sick after 391,4 days of activity. A primary educational intervention was implemented to a total number of 687 pit diggers in five cities of IMR in intend to prevent silicosis. The Paulo Freireâs educational method was used it was applied to the pit diggers to make them learn about the disease and the sickening process, including how to prevent it. The pit diggers actively participated in the educational program content. This was done by person to person contact among health workers and pit diggers; by group reunions and by large popular communications. In the present study, 283 of the 687 pit diggers answered a questionary in order to evaluate the effects of the educational program on the pit diggers learning about the disease and on the pit digging activities. One hundred fifteen (40,6%) of the pit diggers known they had silicosis, 122 (43,1%) known they did not have silicosis and 46 (16,3%) did not know their diagnosis. The results indicated that the educational program was important to control the disease. The majority of the pit diggers, 277 (98,9%) believed that digging pits was related to getting silicosis This believing was not different among silicotics or non-silicotics (p=0,362). Two hundred seventy one (958%) pit diggers learned that the rock dust causes silicosis and 221 (78,1%) learned that silicosis is acquired by digging pits. The pit diggers said that person to person contact was the best way to learn about silicosis. Most of them, 241 (85,8%) interrupted digging activities. This attitude was influenced by the knowledge of their diagnosis. It was more frequent if they known they had silicosis (p=0,001). The most relevant motive to stop digging was the knowledge about the presence of the silicosis among the diggers 211 (89,1%). There was an association between stopping digging and being diagnosed as silicotic (p=0,034). Nevertheless, 174 (77,7%) wished to change theirjob activity. This was not related to their health status (p=0,831). The pit diggers who did not assimilated the educational program or did not change their attitude regarding pit digging consisted a minority. They did not realize their problem and they need further attention to assimilate an educational intervention

A research report submitted to the Faculty of Health Sciences, School of Public Health, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Public Health: Occupational Hygiene, Johannesburg, 2012 / The aim of the study was to determine if the gold mine under study achieved the 2008 elimination of silicosis occupational hygiene milestones as set out by the South African mining industry in 2003. To identify high risk quartz exposed occupations within the conventional stope and TM³ stope employees of an underground gold mine between July 2008 and June 2010; to describe the personal quartz exposure of conventional stope and TM³ stope employees in an underground gold mine between July 2008 and June 2010; and to compare the time weighted average (TWA) quartz exposures between the conventional stope and TM³ stope to the Department of Mineral Resources-Occupational Exposure Limit (DMR-OEL) of 0.1 mg/m3, the National Institute of Occupational Safety and Health-Recommended Exposure Limit (NIOSH-REL) of 0.05 mg/m3 and the American Conference of Government Industrial Hygienists-Threshold Limit Value (ACGIHTLV) of 0.025 mg/m3.

Made available in DSpace on 2016-08-10T10:53:30Z (GMT). No. of bitstreams: 1 FABIOLA CURADO.pdf: 968004 bytes, checksum: 6b4b82075a1b0e1f620232a1879668f9 (MD5) Previous issue date: 2010-11-05 / Silicosis, respiratory disease associated with occupational exposure to crystalline silica represents a serious public health problem, since, in spite of being potentially avoidable, presents high rates of incidense and prevalence, especially in less developed countries. Objectives: measure values of Forced Vital Capacity (FVC), Forced Expiratory Volume in 1 second (FEV1) and Peak Expiratory Flow (PEF), verify the occurrence of respiratory symptoms characteristic of silicosis; test whether there is relevant differences between spirometric values and occurrence of respiratory symptoms length of employment, workers' age and smoking factor; test whether there is correlation between spirometric rates and length of employment, age and smoking habit. Methodology: The study was applied by descriptive analytical transversal methods. The studied sample was composed of workers from six companies in the field of stone processing industry (quarries / marble), one in Goiânia-GO district and the other five in the city of Pirenopolis-GO, totaling 56 workers. The method of data collection consisted in two questionnaires and a portable spirometry equipment. Results: Regarding the use of Collective Protection Equipment (CPE), 100% of the employees answered that there was collective protection, 73% related to ventilation with open shelter shed and 27% with semi-open shelter. Regarding to the exhaust ventilation, 100% of the employees related that there was not this kind of ventilation. Regarding the use of Personal Protective Equipment (PPE), specifically in the case of respiratory protection, the mask filter was used by 20 employees and mask without filter (made of fabric) by 36 employees. It can be stated that 100% of the workers wore masks for personal protection, covering any kind of mask, including inappropriate types. The result of the averages of the three spirometric rates presented a highly significant difference when compared to t normal average of reference (P < 0.0001). In the universe of 56 men surveyed, 40 men were symptomatic (71%). There was no statistically significant differences between spirometric values and exposure time (at about 5 years); symptomatic and asymptomatic; and between smokers and nonsmokers. There was statistically significant differences between spirometric values and age (at about 45 years old). At the correlation test showed that there was no statistically differences between spirometric rates and exposure time, number of cigarettes smoked and length of smoking habit. There was negative correlation between spirometric values and age. Conclusion: it was verified that the employees present a high percentage of symptomatic factor; for spirometric values changed significantly for the three indices studied compared with the reference literature. / Silicose, doença respiratória associada à exposição ocupacional ao cristalino, sílica, representa um sério problema de saúde pública, uma vez que, apesar de ser potencialmente evitável, apresenta altos índices de incidência e prevalência, especialmente nos países menos desenvolvidos. Objetivos: mensurar valores de Capacidade Vital Forçada (CVF), Volume Expiratório Forçado no 1º segundo (VEF) e Pico Fluxo Expiratório (PEF); verificar a presença de sintomas respiratórios, característicos de Silicose; testar se há diferença significativa entre os valores espirométricos e presença de sintomas respiratórios, tempo de serviço, idade dos trabalhadores e fator tabagismo; testar se há correlação entre os índices espirométricos e tempo de serviço, idade e hábito tabagista. Metodologia: o estudo foi do tipo descritivo - analítico, transversal. A população estudada foi composta por trabalhadores de seis empresas do ramo de beneficiamento de pedras (pedreiras/marmorarias), uma no município de Goiânia-GO e as outras cinco no município de Pirenópolis-GO, totalizando 56 trabalhadores. Os instrumentos de coleta de dados foram dois questionários e um equipamento de espitometria portátil. Resultados: em relação ao uso de Equipamento de Proteção Coletiva (EPC), 100% dos funcionários respondeu que existia proteção coletiva; 73% referente à ventilação do galpão aberto e 27% com galpão semi-aberto. Em relação à ventilação exaustora, 100% dos funcionários afirmou que não existia esse tipo de ventilação. Referente ao uso de Equipamento de Proteção individual (EPI), tratando-se especificamente de proteção respiratória, a máscara com filtro era utilizado por 20 funcionários e a máscara sem filtro (tecido) por 36 funcionários. Pode-se afirmar que 100% dos trabalhadores usavam máscaras de proteção individual, abrangendo qualquer tipo de máscara, inclusive não apropriadas. O resultado das médias dos três índices espirométricos apresentou uma diferença altamente significativa quando comparado às médias normais de referência (p < 0,0001). Dos 56 homens pesquisados, 40 homens apresentam-se sintomáticos (71%). Não houve diferença estatística significativa entre valores espirométricos e tempo de exposição (mais ou menos de 5 anos), sintomáticos e assintomáticos e tabagistas e não tabagistas. Houve diferença estatística significativa entre valores espirométricos e idade (mais ou menos de 45 anos). No teste de correlação verificou-se que não houve diferença estatística significativa entre os índices espirométricos e tempo de exposição, número de cigarros fumados e tempo de hábito tabágico. Houve correlação negativa entre os valores espirometricos e idade. Conclusão: verificou-se que os funcionários apresentam um alto percentual de fator sintomático; para os valores espirométricos houve alteração significativa para os três índices pesquisados comparados com a literatura de referência.

M. Tech. / The persistent presence of neutrophils is associated with a wide range of inflammatory diseases. Resolution of inflammation in these diseases is also associated with the ingestion of apoptotic neutrophils by macrophages. Inflammation and apoptosis of inflammatory cells are common known features observed in the lung following exposure to crystalline silica. What is not known is how well these apoptotic cells are cleared by macrophages in the presence of crystalline silica? To investigate the latter, we incubated the U937 macrophages and neutrophils with crystalline silica and found that it could increase their apoptosis and necrosis especially those of the U937 cells. We then examined the ability of crystalline silica to induce the production of cytokines (TNF-α, IFN-γ and IL-1β) as well as NO by these cells. We found that these particles could increase the production of TNF-α, IL-1β and NO but not IFN-γ in a time-and concentration-dependent manner. We also assessed the ability of crystalline silica to alter the levels of GSH in neutrophils and U937 macrophages. We found that it could drastically decrease the levels of this antioxidant in U937 macrophages with no additional effect in neutrophils as these latter cells would have low levels of GSH prior to their incubation with crystalline silica. Finally, we examined the effect of crystalline silica on the ability of U937 macrophages to phagocytose apoptotic neutrophils. We found that while untreated U937 macrophages were able to phagocytose apoptotic neutrophils, the presence of crystalline silica reduced this ability by 15%. Taken together, our results suggest that exposure to crystalline silica impairs the clearance of apoptotic neutrophils by decreasing their phagocytosis by macrophages and thus prevents the resolution of inflammation.