The investigation of the effect of pollination on ribosomal RNA, transfer RNA and DNA contents in styles of Nicotiana alata

Using the phenol extraction method and MAK column chromatography the contents of nucleic acids in styles ofNicotiana alata were estimated before and up to 48 h after compatible pollination. As a result of pollination, high-molecular-weight rRNA and DNA registered a significant increase in their content approximating 30% and 16% respectively. The change in sRNA (4-S tRNA and 5-S rRNA) level was very slight and non-significant. In pollen grains there is an unusually high amount of rRNA with respect to the content of other nucleic acids and the rRNA/tRNA ratio approximates 14 : 1. On the other hand, in non-pollinated styles the content of rRNA is only about 6 times higher than that of tRNA. The changes in nucleic acid level found in styles after pollination are at least in a major part the result of the addition of the nucleic acids present in the amount of pollen used for pollination. The high rRNA level relatively to tRNA being generally associated with rapidly growing cells, its significance in pollen may be related to the rapid growth of pollen tubes

Biomechanics of pelvic ring fixation techniques

This work is supported by the European Regional Development Fund-Project Application of Modern Technologies in Medicine and Industry (No. CZ.02.1.01/0.0/0.0/17 048/0007280) and by the project LO1506 of the Czech Ministry of Education, Youth and Sports under the program NPU I.The study focuses on development of computational tools for prediction and analysis of osteosynthesis of pelvic ring injuries. Fractures of pelvic bones may occur after high-energy impact events such as car accidents or sports injuries. For surgical treatment of unstable fractures either internal or external fixators can be applied in order to support the healing bone structures. In the following, a special attention is paid to minimally invasive internal fixation techniques for management of sacral bone injuries