The novel polymeric potassium complex with a new coordination mode of orotic acid [K(μ5-H2Or)(μ-H2O)]n: Synthesis and structural characterization

Tetra-n-butyl-ammonium orotate monohydrate: knowledge-based comparison of the results of accurate and lower-resolution analyses and a non-routine disorder refinement

The title hydrated mol-ecular salt (systematic name: tetra-n-butyl-ammonium 2,6-dioxo-1,2,3,6-tetra-hydro-pyrimidine-4-carboxyl-ate monohydrate), C16H36N+·C5H3N2O4 -·H2O, crystallizes with N-H⋯O and O-H⋯O hydrogen-bonded double-stranded anti-parallel ribbons consisting of the hydro-philic orotate monoanions and water mol-ecules, separated by the bulky hydro-phobic cations. The hydro-phobic and hydro-philic regions of the structure are joined by weaker non-classical C-H⋯O hydrogen bonds. An accurate structure analysis conducted at T = 100 K is compared to a lower-resolution less accurate determination using data measured at T = 295 K. The results of both analyses are evaluated using a knowledge-based approach, and it is found that the less accurate room-temperature structure analysis provides geometric data that are similar to those derived from the accurate low-temperature analysis, with both sets of results consistent with previously analyzed structures. A minor disorder of one methyl group in the cation at low temperature was found to be slightly more complex at room temperature; while still involving a minor fraction of the structure, the disorder at room temperature was found to require a non-routine treatment, which is described in detail.

[The influence of 'potassium orotate' on neocollagenogenesis in implantation of polypropylene endoprosthesis and polypropylene combined with polylactic acid endoprosthesis]

AIM

To study neocollagenogenesis after implantation of polypropylene endoprosthesis and polypropylene combined with polylactic acid endoprosthesis on background of «potassium orotate» administration.

MATERIAL AND METHODS

We used two different types of endoprosthesis in the experiment. The first type was made of just polypropylene, the second type was made of polypropylene combined with polylactic acid. Histological examination was performed using polarizing microscopy. Collagen types I and III ratio in connective tissue around the prosthesis was analyzed according to the color that was individual for each type.

RESULTS

The results were significantly better in case of collagenogenesis stimulation with Potassium orotate within 30 days and later for one type of endoprosthesis. Also we revealed that collagenogenesis and paraprosthesis capsule formation were more active in case of combined endoprosthesis. We revealed stimulating action of «Potassium Orotate» for collegenogenesis process, this fact was proved by increased collagen I/III ratio.

CONCLUSION

Optimization of collagenogenesis was based on persistent 1,37-fold increase of collagen I/III ratio in case of combined endoprosthesis after 90 days. It was manifested by accelerated formation of connective tissue capsule and facilitated early isolation of the implant from surrounding tissues.