Bacterial Nanocellulose Hydrogels Designed as Bioartificial Medical Implants 193
•. There. were. no. statistical. differences. in. the. diameter. of. the. graft.
before.and.90.days.after.surgery.
•. There.were.no.arteriovenous.fistulae.formations.or.signs.of.hematoma.indicating.bleeding.from.the.grafts.in.the.chronic.course.
This. study. served. as. an. evaluation. of. a. novel. bioengineered. synthetic.
small-caliber. cellulose. graft. using. short. grafts.. Longer. grafts. need. to. be.
verified.concerning.stress.resistance.of.the.wall.and.shear.resistance.of.the.
. neointimal.layer..Therefore,.and.as.a.work.in.progress,.long.segments.of.BNC.
tubes.are.under.investigation.as.vascular.grafts.in.the.carotid.artery.of.sheep.
(graft. length. approximately. 10. cm,. bursting. strength. up. to. 1000  mmHg)..
Thus.far.the.results.demonstrate.very.good.mechanical.stability.of.the.BNC.
grafts.in.the.high.blood.pressure.system.under.nonrestricted.animal.activities.over.3.months.
Conclusions
The. goal. of. this. chapter. was. to. deepen. understanding. and. discuss. recent.
knowledge.in.the.field.of.BNC.materials.for.applications.as.medical.implants..
The.contribution.is.based.on.the.cooperative.work.of.a.truly.interdisciplinary.
team. of. polymer. chemists,. materials. scientists,. biologists,. and. physicians..
The.natural.hydrogel.BNC.appears.to.provide.substantial.combinations.of.
properties. essential. for. a. biomaterial. applicable. as. an. implant. for. crucial.
fields.of.medical.care..Under.proper.control.of.the.biotechnological.formation.of.BNC,.prototypes.of.inlays.for.the.regeneration.of.articular.cartilage.
and. implants. for. blood. vessels. have. been. successfully. produced.. Detailed.
in.vivo.characterization.of.the.performance.of.BNC.implants.(large.animal.
studies).will.be.required,.addressing.in.particular.their.long-term.stability.
and.their.suitability.to.replace.load-bearing.cartilage.or.small-caliber.blood.
vessels.without.significant.thrombogenicity.
References
Ahrem,.H.,.D..Pretzel,.U..Udhart,.and.D..Klemm..2010..Structure.design.for.enhanced.
cell.ingrowth.in.bacterial.nanocellulose.implants..Paper.presented.at.the.239th.
American.Chemical.Society.National.Meeting,.March.23–25,.San.Francisco,.CA.
Andersson,. J.,. H.. Stenhamre,. H.. Baeckdahl,. and. P.. Gatenholm.. 2010.. Behaviour. of.
human.chondrocytes.in.engineered.porous.bacterial.cellulose.scaffolds..J. Biomed.
Mater. Res. A.94A:1124–32.