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In order to develop osteogenic bone substitutes by tissue-engineering, primary human osteoblasts were cultured on the biomaterials tricalcium-phosphate (TCP), hydroxyapatite-collagene, autoclaved cancellous bone and in fibrin glue.

Primary human osteoblasts were cultered on biomaterials to develop living bone substitutes by Tissue Engineering. Monolayer cultures were established from iliac crest biopsies. Single cell suspensions were then seeded onto tricalciumphosphate (TCP) BIOBASE®, hydroxyapatitecollagen(HAC), autoclaved cancellous bone (CB) and fibrin glue (FG) Tissucol® The constructs were analyzed by electronmicroscopy, Cell proliferation assay (XTT) and histology to assess adhesion, proliferation and extracellular matrix formation on the biomaterial.The osteoblastic cells survived in the fibrin glue and established a mesenchymal phenotype. They adhered to the HAC-sponges, TCP and CB. Prolifertion was seen on TCP and CB. HAC had a suppressive effect on the cells. An inmature matrix was found on TCP and a bone neomatrix on CB after 4 weeks in vitro.

We have recently shown that TGF-beta-treated normal fibroblasts are able to induce apoptosis of transformed fibroblasts, leading to their elimination. Here we describe a test system that allows the quantitative analysis of the elimination of G418-resistant transformed cells by TGF-beta-treated normal cells. This assay system was used to screen for substances that interfere with the elimination of transformed cells. Catechol and hydroquinone, but not resorcinol, were found to represent potent antagonists of TGF-beta-induced elimination of transformed cells by normal cells. Protection of transformed cells from negative effects derived from their cellular environment defines a hitherto unrecognized crucial mechanism for the survival of transformed cells. The protective effect of catechol as seen in this experimental system may act in concert with its co-carcinogenic and promoting activities during carcinogenesis.

In a rectifier system with inductive load circuit the current fluctuations correspond to the time integral of the voltage absorbed by the inductance, while in a circuit with an L-C filter the current ripple is defined by the harmonic composition of the output voltage. Both calculations are rather complex; however, once computed, the results are generally valid. Therefore, this work has been done by the author, and for all operating conditions of interest the results are presented by this paper.

Auf der 18. Tagung der Deutschen Gesellschaft fur Geschichte der Medizin und der Naturwissenschaften zu Bad Bruckenau, habe ich einer Anregung Sudhoffs folgend „Uber den Stand der Augenheilkunde gegen Ende des Mittelalters (etwa 1400)“ berichtet. Aus den „Sermones medicinales“des Niccolo Falcucci, welche um 1400 das vollstandigste Sammelwerk uber alle Gebiete der Medizin bilden, habe ich von den Kapiteln uber Augenheilkunde eine deutsche Ubersetzung gegeben. Nicolaus Florentinus, wie er auch genannt wird, ist wahrscheinlich 1357 in Florenz geboren und 1430 gestorben. Er stutzt sich in seiner Arbeit auf eine Reihe von namhaften arabischen Arzten, die Augenarztliches in ihren Werken hinterlassen haben. Heute mochte ich auf die Augenheilkunde von Lanfranchi, der wahrscheinlich vor 1306 gestorben ist, aufmerksam machen. Lanfranchi gehorte zu jenen Wundarzten Italiens, die im 13. Jahrhundert aus der Schule von Bologna hervorgegangen sind und die Chirurgie wissenschaftlich bearbeitet haben. Sie haben auch die operative Therapie der Augenkrankheiten, die im Mittelalter von den Arabern in verdienstvoller Weise gefordert wurde, im Abendlande zu Studienzwecken ins Lateinische ubersetzt und weiter verarbeitet.