Parallel to the growing role of tissue engineering, the need for cell embedding materials, which allow cells to stabilise in a three-dimensional distribution, has increased. Although several substances have been tested, fibrin is thus far the only one that permits the clinical application of cultured tissue. To date, autologous fibrinogen has usually been polymerised with bovine thrombin, which can cause severe immunological side effects. The objective of this study was to explore the practicability of obtaining autologous thrombin from a single patient in an adequate concentration and amount. Fibrinogen was cryoprecipitated from 200 ml of freshly-frozen plasma. Thrombin was isolated from the supernatant through ion-exchange chromatography. The thrombin was first bound to Sephadex A-50 and then eluated using 2 ml of a salt buffer (2.0 M NaCl in 0.015 M trisodiumcitrate, pH 7.0). The activity of the thrombin (51 NIH x ml(-1) to 414 NIH x ml(-1) reached levels comparable to those in commercially available fibrin glues (4-500 NIH x ml(-1)). The study has shown that it is possible to obtain a sufficient amount of autologous thrombin from a single donor to create a fibrin matrix of high efficiency without the risk of immunological and infectious side effects.

Aus den durch Wasserdampfdestillation gewonnenen atherischen Krautolen von Artemisia vulgaris L. sowie Artemisia dracunculus L. wurde erstmals der Sesquiterpenalkohol Spathulenol isoliert und charakterisiert.Substances First Isolated from the Essential Oils of two ArtemisiaSpecies, 1. Spathulenol, an Azulenogenic CIS-AlcoholSpathulenol is one of the sesquiterpenic alcohols which is isolated from the essential oils o f Artcmisia vulgaris L. and Artcmisia dracunculus L.. It is the first time this substance has been found in these volatile oils. 1 E. Stahl und H. Jork in E. Stahl: Handbuch der DunnschichtChromatographie, Kap. J , 2. Aufl., Springer-Verlag, Berlin-Heidelberg-New York 1967.

Defatted linseed flour was prepared from cold-pressed seed meal via hexane extraction of the residual oil, followed by removal of the major portion of the hulls through grinding and sieving (sieve size 0.25mm). The resulting flour had 50% protein on a dry basis compared with 40% contained by the whole seed on an oil-free dry basis. Nitrogen extractability of the defatted flour in water was not influenced by the length of the extraction period but an increased extraction was observed at higher so1id:liquid ratios up to the studied limit of 1:40. The smallest amount of nitrogen (20%) was extracted in the pH range 4.0-4.6 and the greatest (80%) at pH 12.0. Addition of NaCl (0.1-1.0~) broadened the pH range of minimum nitrogen extractability and shifted it towards lower pH region. At higher concentrations (0.6 and 1.0 M) NaCl markedly increased nitrogen extractability in the pH range of 4.0 to 8.0. Precipitation of protein from an extract at pH 10.0 was maximum (77%) at pH 4.1. A higher buffer capacity of the flour was observed in the acidic medium (0.204 mmol HCI g-flour) than in the alkaline medium (0.096 mmol NaOH g-' flour).

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