title: [Non-antagonistic influence of Krumeich's intrastromal corneal ring in an experimental tissue culture system].
abstract: BACKGROUND
  Intrastromal insertion of Krumeich's corneal ring between graft and residual host corneal tissue appears to impair preripheral, superficial and superfluous vascularization of donor corneal tissue.
  
  
  OBJECTIVE
  The purpose of this study was to investigate the cytotoxic effects of Krumeich's ring using tissue cultures composed of primary human dermal microvascular endothelial cells from adult donors (HMVEC).
  
  
  METHODS
  Soluble growth medium extracts of the individual components of Krumeich's ring alloy were prepared and HMVEC were exposed to these extracts in triplicate for 1 day followed by investigation with 3‑(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Furthermore, HMVEC were cultured for 5 days on either Krumeich's ring or polypropylene (PP) discs coated with individual components of the Krumeich's ring alloy followed by double vital staining with fluorescein diacetate (FDA) and propidium iodide (PI).
  
  
  RESULTS
  The MTT assays revealed that higher doses of the extracts appeared to reduce the viability of HMVEC, while highly diluted extracts of molybdenum (Mo) powder appeared to increase the metabolic activity of HMVEC. The FDA-PI staining showed only a few live HMVEC on either cobalt (Co) or Mo-coated PP discs, compared to the respective titanium (Ti) and chromium (Cr) counterparts. Viable HMVEC appeared to attach to Krumeich's ring after a 5‑day incubation period.
  
  
  CONCLUSIONS
  The results confirm that Krumeich's ring does not exert measurable cytotoxic effects in our chosen assay system. High dilutions of medium-soluble Mo powder extracts appear to increase the metabolic activity of HMVEC.
authors.affiliation: Fraunhofer-Institut für Angewandte Polymerforschung IAP, 14476, Potsdam-Golm, Deutschland.
authors.forename: C
authors.initials: C
authors.lastname: Schmidt
authors.affiliation: HumanOptics AG, Erlangen, Deutschland.
authors.forename: S
authors.initials: S
authors.lastname: Fabinyi
authors.affiliation: Fraunhofer-Institut für Angewandte Polymerforschung IAP, 14476, Potsdam-Golm, Deutschland.
authors.forename: S
authors.initials: S
authors.lastname: Rehfeldt
authors.affiliation: Fraunhofer-Institut für Angewandte Polymerforschung IAP, 14476, Potsdam-Golm, Deutschland.
authors.forename: S
authors.initials: S
authors.lastname: Klöpzig
authors.affiliation: Fraunhofer-Institut für Angewandte Polymerforschung IAP, 14476, Potsdam-Golm, Deutschland.
authors.forename: V
authors.initials: V
authors.lastname: Jentzen
authors.affiliation: Fraunhofer-Institut für Angewandte Polymerforschung IAP, 14476, Potsdam-Golm, Deutschland.
authors.forename: J
authors.initials: J
authors.lastname: Bohrisch
authors.affiliation: HumanOptics AG, Erlangen, Deutschland.
authors.forename: A
authors.initials: A
authors.lastname: Messner
authors.affiliation: Fraunhofer-Institut für Angewandte Polymerforschung IAP, 14476, Potsdam-Golm, Deutschland. joachim.storsberg@iap.fraunhofer.de.
authors.forename: J
authors.initials: J
authors.lastname: Storsberg
mesh_terms: D002470:Cell Survival / Q000187:drug effects*; D002478:Cells, Cultured; D016039:Corneal Transplantation / Q000009:adverse effects* / Q000295:instrumentation; D042783:Endothelial Cells / Q000187:drug effects* / Q000473:pathology / Q000502:physiology*; D006801:Humans; D008422:Materials Testing; D008670:Metals / Q000009:adverse effects*; D019736:Prostheses and Implants / Q000009:adverse effects*; D046509:Tissue Culture Techniques
chemical_list: D008670:Metals
keywords: Alloy; Biomaterial; Cytotoxicity; Krumeich; Vascularization