16 research outputs found

    Addressing the contribution of previously described genetic and epidemiological risk factors associated with increased prostate cancer risk and aggressive disease within men from South Africa

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    BACKGROUND: Although African ancestry represents a significant risk factor for prostate cancer, few studies have investigated the significance of prostate cancer and relevance of previously defined genetic and epidemiological prostate cancer risk factors within Africa. We recently established the Southern African Prostate Cancer Study (SAPCS), a resource for epidemiological and genetic analysis of prostate cancer risk and outcomes in Black men from South Africa. Biased towards highly aggressive prostate cancer disease, this is the first reported data analysis. METHODS: The SAPCS is an ongoing population-based study of Black men with or without prostate cancer. Pilot analysis was performed for the first 837 participants, 522 cases and 315 controls. We investigate 46 pre-defined prostate cancer risk alleles and up to 24 epidemiological measures including demographic, lifestyle and environmental factors, for power to predict disease status and to drive on-going SAPCS recruitment, sampling procedures and research direction. RESULTS: Preliminary results suggest that no previously defined risk alleles significantly predict prostate cancer occurrence within the SAPCS. Furthermore, genetic risk profiles did not enhance the predictive power of prostate specific antigen (PSA) testing. Our study supports several lifestyle/environmental factors contributing to prostate cancer risk including a family history of cancer, diabetes, current sexual activity and erectile dysfunction, balding pattern, frequent aspirin usage and high PSA levels. CONCLUSIONS: Despite a clear increased prostate cancer risk associated with an African ancestry, experimental data is lacking within Africa. This pilot study is therefore a significant contribution to the field. While genetic risk factors (largely European-defined) show no evidence for disease prediction in the SAPCS, several epidemiological factors were associated with prostate cancer status. We call for improved study power by building on the SAPCS resource, further validation of associated factors in independent African-based resources, and genome-wide approaches to define African-specific risk alleles

    Knowledge Transfer and Exchange Processes for Environmental Health Issues in Canadian Aboriginal Communities

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    Within Canadian Aboriginal communities, the process for utilizing environmental health research evidence in the development of policies and programs is not well understood. This fundamental qualitative descriptive study explored the perceptions of 28 environmental health researchers, senior external decision-makers and decision-makers working within Aboriginal communities about factors influencing knowledge transfer and exchange, beliefs about research evidence and Traditional Knowledge and the preferred communication channels for disseminating and receiving evidence. The results indicate that collaborative relationships between researchers and decision-makers, initiated early and maintained throughout a research project, promote both the efficient conduct of a study and increase the likelihood of knowledge transfer and exchange. Participants identified that empirical research findings and Traditional Knowledge are different and distinct types of evidence that should be equally valued and used where possible to provide a holistic understanding of environmental issues and support decisions in Aboriginal communities. To facilitate the dissemination of research findings within Aboriginal communities, participants described the elements required for successfully crafting key messages, locating and using credible messengers to deliver the messages, strategies for using cultural brokers and identifying the communication channels commonly used to disseminate and receive this type of information

    A dose audit of fluoroscopy examinations at Charlotte Maxeke Johannesburg Academic Hospital: Analysis of preliminary results

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    Purpose: To retrospectively analyze the radiation doses delivered to patients undergoing fluoroscopy examinations in terms of the skin dose and the dose-area product (DAP). Materials and Methods: The subjects of this study were patients who underwent fluoroscopy examinations at Charlotte Maxeke Johannesburg Academic Hospital, South Africa during the period August 2007 to March 2008. The skin dose and dose-area product values were obtained from a built-in DAP-meter installed on a digital Philips Medical Systems MultiDiagnost Eleva fluoroscopy unit. The following cases were analyzed namely barium swallow, barium meal, barium enema, hexabrix swallow, gastrografin meal, voiding cystourethrogram, fistulogram, myelogram, nephrostomy and loopogram. Results: An analysis of three hundred and thirty one examinations is presented. From the recorded data the following quantities were deduced: the mean- and range of the skin doses and DAPs, mean screening time and mean fluoroscopy duration. An analysis of the screening time for the various examinations showed a weak correlation (r = 0.59) between skin dose and screening time, while a poor correlation (r = 0.42) was deduced between DAP reading and screening time. Conclusion: There is a wide spread in the radiation doses registered for any one given type of examination. The large variability in the radiation dose delivered proves that fluoroscopic examinations stand to gain from dose optimization. The usefulness and potential use of DAP meters with regards to dose optimization in radiology is shown. In line with efforts to optimize dose from diagnostic radiography examinations the authors recommend the establishment of diagnostic reference levels (DRLs) in South Africa for the most frequent examinations in general radiography, fluoroscopy, mammography and computed tomography. Keywords: patient dose, genetic risk, dose optimization, dose reference level

    Clinical presentation of prostate cancer in black South Africans

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    Background: Compared with White Americans, Black American men are at a significant increased risk of presenting with prostate cancer (PCa) and associated mortality, suggesting a link to African-ancestry. However, PCa status within Africa is largely unknown. We address the clinical presentation of PCa within Black South African men. Methods: Over 1,000 participants with or without PCa have enrolled in the Southern African Prostate Cancer Study (SAPCS). Using genome-wide profiling we establish a unique within Africa population substructure. Adjusting for age, clinical variables were assessed, compared against Black Americans and between rural and urban localities while addressing potential socio-demographic confounders. Results: We report a significant difference in the distribution of prostate specific antigen (PSA) levels skewed towards higher PSA levels in the PCa cases (83.0% present with a PSA ≥ 20 µg/L; median PSA = 98.8 µg/L) relative to men with no detectable PCa (18.5% present with a PSA ≥ 20 µg/L; median PSA = 9.1 µg/L). Compared with Black Americans, Black South Africans presented with significantly more aggressive disease defined by Gleason score >7 (17% and 36%, respectively) and PSA ≥ 20 µg/L (17.2% and 83.2%, respectively). We report exasperated disease aggression defined by Gleason score >7 (P = 0.0042) and poorly differentiated tumor grade (P < 0.0001) within rural versus urban localities. Conclusion: Black South African men present with higher PSA levels and histopathological tumor grade compared with Black Americans, which is further escalated in men from rural localities. Our data suggests that lack of PSA testing may be contributing to an aggressive PCa disease phenotype within South African men.12 page(s

    Setting up the Brazilian Evaluation Network: a challenging work with no boundaries Estabelecendo a Rede Brasileira de Avaliação: um trabalho desafiador sem limites

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    Evaluation may be a relevant tool for the practice of democracy. In order for it to occur, quality and proper utilization of its results must be assured (PATTON, 1997). Therefore, the consolidation of democratic principles in a society and the promotion of effective social interactions (FETTERMAN; WANDERSMAN, 2005) will benefit enormously from a greater and better use of evaluation in all possible formats. The Brazilian Evaluation Network was created approximately three years ago in a country with a recent history of democratic practice. Within a theoretical framework networks do not have boundaries or limits for debate. However, cultural and historical aspects create limits for the discussions and boundaries among its participants. This paper intends to shed light into some of these limits and boundaries, reflecting over how they are being overcome.<br>Uma avaliação pode ser um importante instrumento para o exercício da democracia. Para que isso ocorra é preciso assegurar a qualidade da avaliação, bem como a utilização apropriada dos seus resultados (PATTON,1997). Desta forma, a construção de uma sociedade democrática, que busca a melhoria permanente dos seus processos sociais (FETTERMAN; WANDERSMAN, 2005), depende do aprimoramento contínuo da sua prática de avaliação, em suas variadas manifestações. No Brasil, há aproximadamente 3 anos, foi criada a Rede Brasileira de Avaliação. Uma rede que, em sua concepção teórica, não possui limites ou fronteiras de discussão. Contudo, existem aspectos culturais e históricos (envolvendo valores), que criam limites para as referidas discussões e estabelecem fronteiras entre as diferentes instâncias. Este trabalho apresenta alguns destes limites e fronteiras, refletindo sobre a forma como aqueles que encomendam e que conduzem avaliações vêm contornando os limites e ultrapassando fronteiras
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