Synthetic hydrophilic polymers

Synthetic hydrophilic polymers find promising applications in pharmacology, biotechnology and chemistry. The biocompatibility, biodegradability and pharmacological activity of these polymers depend much on their hydrophilic nature. This article summarizes the recent developments in the utilization of the different classes of these hydrophilic polymers as pharmacologically active agents, for enzyme modification and as catalysts and supports for chemical reactions.     

Morphogene substanzen ausHydra

We use hydra as a model system to understand how growth and differentiation and, as a consequence of this, pattern formation are controlled at the molecular level. We have found that four substances control head and foot formation in hydra: an activator and an inhibitor of head formation and an activator and an inhibitor of foot formation. The two activators are peptides with molecular weights around 1000 daltons, the inhibitors are smaller in molecular weight (<500), have an overall positive charge and do not contain peptide bonds. In normal animals all four substances are present and most likely produced by nerve cells. We hope to understand how these substances act and interact to create the spatial and temporal pattern of growth and differentiation typical for hydra.     

The use of amniotic fluid AFP action limits in diagnosing open neural tube defects

An analysis is made of alphafetoprotein (AFP) concentrations in 3630 amniotic fluids submitted for prospective prenatal diagnoses over a 7-year period. There were 89 cases of anencephaly, 74 of open spina bifida and 3467 with normal singleton outcomes. The AFP data were expressed in both standard deviations above the mean and multiples of the normal median for individual weeks of gestation. False positive and false negative rates were comparable in the two systems at selected cut-offs. It is concluded that either system may be used in setting action limits for the primary distinction of unaffected pregnancies from those in which an open neural tube defect is present.