RESUMEN
OBJECTIVE: To determine the molecular basis and establish a routine molecular diagnostic service for familial adenomatous polyposis coli (FAP) families in South Africa. DESIGN: The coding region of the adenomatous polyposis coli (APC) gene in affected FAP kindreds was screened using heteroduplex analysis, single-strand conformation polymorphism analysis and the protein truncation test. SETTING: Department of Human Genetics, University of Stellenbosch, and the Cancer Research Campaign Laboratories, Department of Pathology, University of Edinburgh and Molecular Medicine Centre, Western General Hospital, Edinburgh, Scotland (academic visit of 6 months). SUBJECTS: FAP-affected individuals and at-risk family members in 28 apparently unrelated South African families. RESULTS: A total of nine different APC mutations was identified, allowing DNA-based diagnosis in 20 families. Three of these mutations have not been described previously in other populations. CONCLUSION: Pre-symptomatic diagnosis using direct mutation detection is cost-effective and surgical intervention has the potential to prevent cancer in at-risk individuals from FAP families.
Asunto(s)
Poliposis Adenomatosa del Colon/genética , Pruebas Genéticas/métodos , Mutación/genética , Poliposis Adenomatosa del Colon/diagnóstico , Codón , ADN de Neoplasias/análisis , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Masculino , Linaje , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Sudáfrica/epidemiologíaRESUMEN
In this article we present an example of our method for instrument development. This method is called the Development Cycle. It consists of four main stages: (1) defining the requirements for an instrument; (2) research, design and pilot testing; (3) implementation and (4) evaluation. An application of the Development Cycle was realized within a project for the development of a basic questionnaire about work and health, to be used at periodic health surveys. This questionnaire had to identify work and work-related health problems in employees with divergent occupations and working conditions. The design of the instrument and the results of its trial in 517 employees is presented. The evaluation of the test results and the modification of the questionnaire are discussed. From 1995, the questionnaire has been implemented in the Dutch OHS services quite successfully.
Asunto(s)
Salud Laboral , Encuestas y Cuestionarios , Encuestas de Atención de la Salud , Humanos , Política Organizacional , Proyectos PilotoRESUMEN
A literature review was performed on the subject of combined exposure to stressors in the working situation. A general, dynamic model of workload served as the theoretical framework for the study. In this model, every factor that triggers a physiological or psychological response in the worker is regarded as a stressor. Decision latitude plays an important role in the model. A quantitative and qualitative analysis was performed on the available literature. It was concluded that the stressors that appear in studies on combined exposure stem mostly from the physical, chemical and biological environment. The task contents, the labor conditions, social relationships at work and the decision latitude are considerably less often studied in relation to combined exposure. It is concluded that important concepts in the study of combined exposure (e.g. interaction, independence, synergism, antagonism) are often quite carelessly mentioned in the literature. Explicit definition of these concepts is lacking in many publications. Establishment of maximum exposure levels is not yet possible for most stressor combinations. Examples are given of combinations that do allow more or less definite conclusions. It is recommended that more studies should be interdisciplinary organized. More studies are necessary in the field, studying effects of long exposure periods in the working population instead of studying students in laboratory situations. Exposure of susceptible groups, such as older workers and partially disabled workers, deserves special attention.