Inhibitory Effects of the Aerial Parts of Epimedium koreanum on TPA-Induced Inflammation and Tumour Promotion in Two-Stage Carcinogenesis in Mouse Skin
Pages 35-42
Ken Yasukawa, Sung-Kwon Ko and Wan-Kyunn Whang
DOI: http://dx.doi.org/10.6000/1927-5951.2016.06.02.1
Published: 27 April 2016

Abstract: Cancer prevention by supplements offers the most cost-effective long-term health strategy. Methanol extracts from the aerial parts of Epimedium koreanum were previously found to inhibit 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammatory ear oedema and tumour promotion by TPA in the two-stage mouse skin carcinogenesis model. Four prenyl flavonol glycosides (1‒4) were isolated from the active fraction of this extract, and were identified. The isolated compounds showed inhibitory activity against TPA-induced ear inflammatory ear oedema. The 50% inhibitory dose (ID₅₀) of icariin (1), epimedin A (2), epimedin B (3) and epimedin C (4) for TPA-induced inflammation ranged from 114 to 255 nmol/ear, suggesting greater potency than indomethacin (ID₅₀: 908 nmol/ear), an anti-inflammatory drug. Thus, the epimedium herb may be useful in cancer prevention.

Keywords: Cancer chemoprevention, antitumour-promoting activity, two-stage carcinogenesis, prenyl flavonol glycosides, Epimedium koreanum.

Myths and Facts about Placebo
Pages 43-54
Hans-Joachim Kremer

DOI: http://dx.doi.org/10.6000/1927-5951.2016.06.02.2

Published: 27 April 2016

Abstract: Many patients, physicians, and sometimes even academics have questionable perceptions of placebo and the so-called placebo effect, Many believe that placebo have its own effects. Although psychological aspects, namely expectations of patients or the persuasive power of the physicians, might sometimes be substantial, such aspects may have little or even no relevance in other situation where placebo control is essential nevertheless. Even in settings where psychological effects should be envisaged, their extent is usually highly variable, indicating that other factors might still exceed the importance of psychological effects. Placebo is defined in US regulations as an inactive preparation designed to resemble the test drug as far as possible. This means that placebo itself cannot be effective. If it would, its correctness is challenged and it should be replaced if still possible. And as placebo is not effective, it can also not have secondary effects, vulgo side effects. Placebo is always used for two reasons: To control bias and to provide the reasonably largest delta, i.e. the difference between two treatments. Placebo should never be interpreted as being able to cause effects.

Keywords: Placebo-effect, definition, bias, delta, nocebo.