RESUMEN
Chemical sterilisation methods for musculoskeletal transplants have the problem of penetration into all tissue strata. The present study examined if a peracetic acid/ethanol solution penetrated to a sufficient extent into specifically prepared femoral heads. To this effect, 10 femoral heads have been provided with drillings (diameter 2 mm, depth 10 mm) at a distance of 15 mm (series B) and placed in a diffusion chamber with sterilisation solution. From an additional central drilling at the femoral neck junction, the sample drawing was made after 30 min each over a period of 4 h for the iodometric determination of peracetic acid (PAA) concentration. Ten femoral heads, which did contain only the central drilling, served as controls (series A). In 9 of the examined femoral heads of series A the defined minimum concentration of PAA of 0.2% (inactivation of bacteria, spores, fungi) has been clearly exceeded over the complete period of measurement. About 0.8% PAA (inactivation of viruses) was achieved within 4 h only with six femoral heads. Nine out of the 10 examined femoral heads in series B show a clearly improved penetration behaviour which was expressed in smaller standard deviations, a faster increase in concentration, as well as in higher starting and final concentrations (approx. 0.9%) of PAA. Previous drying in air leads to a faster penetration into the centre of the bone. Standardised drilling of de-cartilaged femoral heads creates favourable conditions for the penetration of the PAA sterilisation solution into the whole tissue and guarantees a sufficient inactivation of microorganisms.
Asunto(s)
Trasplante Óseo , Cabeza Femoral/efectos de los fármacos , Ácido Peracético/farmacología , Esterilización , Cabeza Femoral/trasplante , Humanos , Factores de Tiempo , Bancos de Tejidos , Trasplante HomólogoRESUMEN
The reduction-cascade of PETN is described as a combination of cyclic-voltammetric measurements and analytical results together with synthesis of PETN-metabolites; furthermore the electroreduction of pentaerythityldinitrate (PEDN) in the presence and absence of cystine as well as cystine and electrogenerated superoxide-radicalanions to elucidate the interaction of PETN with thiol-species. PETN was recognized as precursor for a initial radicalic process, followed by intermediate formation of pentaerythityltrinitratealdehyde (PENA) inside a self-reducing nitrate-system with NO as final product, which may explain its special position in comparison with other pharmaceutically applied nitratestructures. It could be proved, that a cystine-pool reacts as a selective moderator inside the reduction of PEDN without being interfered by O2.-, yielding pentaerythitylmononitrate (PEMN) meanwhile in the absence of cystine only pentaerythrite (PE) is formed.