Recommendations of the ESGE workshop on Ethics in Gastrointestinal Endoscopy-Based Research. First European Symposium on Ethics in Gastroenterology and Digestive Endoscopy, Kos, Greece, June 2003

Impact of endoscopy-based research on quality of life in healthy volunteers

AIM: To study the impact of an endoscopy-based long-term study on the quality of life in healthy volunteers (HV).

METHODS: Ten HV were included into a long-term prospective endoscopy-based placebo-controlled trial with 15 endoscopic examinations per person in 5 different drug phases. Participants completed short form-36 (SF-36) and visual analog scale-based questionnaires (VAS) for different abdominal symptoms at days 0, 7 and 14 of each drug phase. Analyses were performed according to short- and long-term changes and compared to the control group.

RESULTS: All HV completed the study with duration of more than 6 mo. Initial quality of life score was comparable to a general population. Analyses of the SF-36 questionnaires showed no significant changes in physical, mental and total scores, either in a short-term perspective due to different medications, or to potentially endoscopic procedure-associated long-term cumulative changes. Analogous to SF-36, VAS revealed no significant changes in total scores for pathological abdominal symptoms and remained unchanged over the time course and when compared to the control population.

CONCLUSION: This study demonstrates that quality of life in HV is not significantly affected by a long-term endoscopy-based study with multiple endoscopic procedures.

The effect of single-dose naproxen on eicosanoid formation in human gastroduodenal mucosa

BACKGROUND

In animal studies, aspirin and non-aspirin non-steroidal anti-inflammatory drugs contribute to gastroduodenal damage via cyclo-oxygenase inhibition and consecutive leucotriene formation (COX-LOX eicosanoid shunt).

AIM AND METHODS

Ten Helicobacter pylori-negative healthy volunteers received a single dose of 500 mg naproxen to address two questions: (i) is there a crosstalk between eicosanoids before medication in the human gastroduodenal mucosa and (ii) can we demonstrate a COX-LOX shunt following single-dose naproxen?

RESULTS

Significant correlations in the stomach mucosa before medication were obtained between leucotriene B4 (LTB4) and thromboxane B(2) (TxB(2); r = -0.38, P = 0.05), as well as LTB4 and prostaglandin E(2) (PGE(2); r = 0.71, P < 0.0001). In serum, a >90% inhibition of TxB(2) and PGE(2) occurred within 30 min of naproxen administration. In gastric mucosa, a significant decrease of TxB(2) occurred already at 15 min and preferably in the antrum. For LTB4 there was a non-significant trend towards a transient increase. Mucosal PGE(2) was unchanged in all regions; transcript levels of both cyclo-oxygenases/5-lipoxygenase were unaffected (except for a trend of increasing cyclo-oxygenase-2 in the corpus).

CONCLUSIONS

Baseline correlations between LTB4-TxB(2) and LTB4-PGE(2) reflect a crosstalk between these eicosanoids. A COX-LOX shunt; however, cannot be demonstrated following single-dose naproxen in a low-risk population.

Informed consent for molecular-based diagnostic and prognostic studies in the cancer patient

The consent of the subject who is donating cells, tissues, organs or body fluid for research purposes is a precondition for biomedical research on human samples. Before such consent can be obtained, comprehensive information should be provided to the subject by the investigators. This information includes the scope of research, the intended use of subject's body parts and associated data, the risks and benefits associated with the research project, and the right to withdraw their consent at any time without prejudice. Consent is free and must not be obtained under any kind of pressure. The traditional practice of obtaining consent for unspecified future use of biological samples and data generated from clinical trials is no longer adequate for genetic research. However, the investigator has still interest to keep the definition of the field of research as broad as possible. Privacy is an issue of importance for the patient, who is the primary supplier of human samples, and for his relatives. Benefit sharing is another field of contradictory discussion. Normal volunteers are a special case among gene expression studies. An example of informed consent form is provided.