Gentechnik und Biologische Sicherheit

A "European Biosafety Workshop on the Uncontained Use of Modified Organisms in the Environment" was held in Berlin on 27-30 November 1988. The author's concluding remarks are given here in a free German translation. The article briefly summarizes the overall conditions for a general evaluation of potential benefits and risks that may be associated with the use of genetically modified organisms.     

Rodlet Cells in the Head and Trunk Kidney of the Domestic Carp (Cyprinus carpio): Enigmatic Gland Cells or Coccidian Parasites?

 Rodlet cells have been found in the head and trunk kidneys of the common carp (Cyprinus carpio L.). From an experimental sample of 50 carps of various ages, we detected these cells in only seven fishes, contradicting the hypothesis that they constitute a normal component of the fish epithelia. The rodlet cells have a typical structure: 12–16 μm in diameter, with a basal nucleus various in form, and an encasing layer of fibrillar structure. The cells contain rodlets, composed of elongated, opaque sacs featuring dark rods in the center, which strongly elongate in ripening cells. Remarkable pseudopodia-like extensions from the apical parts of the rodlet cells penetrate into the delicate blood vessels and sinusoids of the organs. The encasing layer at the cell apex then opens to release the rodlets into the bloodstream. No junctions were found between the rodlet cells and neighboring cells. It is suggested that these cells comprise some kind of "symbiosis" between leukocyte, possible granulocyte cells, and the parasitic rodlets. The cells serve the rodlets as an incubation chamber, as well as a means of transportation into the bloodstream after ripening. Received: 29 December 1998 / Accepted in revised form: 3 March 1999     

Sonographic demonstration of fetal sacrococcygeal teratoma

Six cases of sonographically diagnosed fetal sacrococcygeal teratoma (SCT) are presented and illustrate the variable features of fetal SCT. The sonographic findings assisted the parents and perinatal team in making decisions, and in two of the cases the children survived after elective Cesarean section and prompt neonatal resection of the tumors. None of the patients showed signs of malignant degeneration of the teratoma or metastases. Fetal SCT no longer should be considered a uniformly fatal condition. The literature on sacrococcygeal teratoma detected after birth indicates that the mortality rate is correlated with the degree of extension of the tumor. Therefore, the classification of sonographically diagnosed fetal SCT according to its size and position is important for decisions regarding pregnancy management.     

Prebiotic polypeptides and the origin of biological information

Recent data on the origin of biological information are reviewed. These data corroborate the view that polyamino acids were the first informational polymers. The source of information is seen in the chemical reactivity of amino acids, their prebiotic abundance and the prebiotic environment. Evidence is presented in favor of Matsuno's protohypercycle that may have preceded Eigen's hypercycle, but that involves a translation of information from polypeptides into that of polynucleotides.