Based on a screening program of medicinal plants for their possible calcium antagonistic mode of action, the most active lipophilic extract of Ammi visnaga fruits (DAB 10) was fractionated by CC and investigated pharmacologically at K+ (60 mM)-depolarized guinea-pig aortic strips. Visnadin, khellin, and visnagin were identified and determined as the effective principles in this testing model with the dihydropyranocoumarin visnadin being the most active. Further selectivity tests against norepinephrine (100 microM)-induced contractions evaluated a possible pharmacological differentiation between these compounds as the furanochromones khellin and visnagin inhibited both spasms to a similar extent while visnadin's activity was significantly higher against K(+)-spasms, suggesting an involvement of a calcium channel blocking mode of action for visnadin.

Fourteen different extracts of nine vasoactive medicinal plants used in European and African phytotherapy and traditional medicine were pharmacologically tested for their possible calcium antagonistic mode of action. The criteria for the selection of plants were: use in traditional medicine in the treatment of cardiovascular diseases, 'nonspecific' spasmolytic activity (mode of action not known), natural compounds with structural similarities to already known 'calcium-antagonists' or calcium-antagonists that have been found in species of the same tribe. All plant extracts were investigated against contractions of aortic strips induced by K+-depolarization. Extracts derived from Ammi visnaga, Cuajacum officinale, Olea europaea, Peucedanum ostruthium and Ruta graveolens showed a clear activity, while Cryptolepis sanguinolenta, Leonurus cardiaca, Passiflora incarnata and Solidago gigantea showed no effect in this test. A comparison between K+-and norepinephrine-induced contractions evaluated the selectivity of the inhibition, which is demonstrated by the isolation and identification strategy for the Ca++-antagonistic principles of Olea europaea leaves and Peucedanum ostruthium rhizomes.

used as the reference substance in the tests. Verapamil inhibited depolarization induced uptake of 45Ca2 to give an IC50 of 2.0 pg/mi. Archangelicin (1) had an 1C50-value of 1.2 pg/mi, and was the most active of the coumarins investigated. The other coumarins inhibited 45Ca2 uptake as presented in Table 1. All the coumarins from the A. archangeliea had a significant calcium antagonistic activity according to this in vitro test. These results support the wide use of this plant in folk medicine.

This paper presents COAST, a web-based application to easily and automatically enhance syllable structure, word stress, and spacing in texts, that was designed in close collaboration with learning therapists to ensure its practical relevance. Such syllable-enhanced texts are commonly used in learning therapy or private tuition to promote the recognition of syllables in order to improve reading and writing skills.In a state of the art solutions for automatic syllable enhancement, we put special emphasis on syllable stress and support specific marking of the primary syllable stress in words. Core features of our tool are i) a highly customizable text enhancement and template functionality, and ii) a novel crowd-sourcing mechanism that we employ to address the issue of data sparsity in language resources. We successfully tested COAST with real-life practitioners in a series of user tests validating the concept of our framework.