TY  - JOUR
A1  - Schmid, Rafael
A1  - Schmidt, Sonja K.
A1  - Hazur, Jonas
A1  - Detsch, Rainer
A1  - Maurer, Evelyn
A1  - Boccaccini, Aldo R.
A1  - Hauptstein, Julia
A1  - Teßmar, Jörg
A1  - Blunk, Torsten
A1  - Schrüfer, Stefan
A1  - Schubert, Dirk W.
A1  - Horch, Raymund E.
A1  - Bosserhoff, Anja K.
A1  - Arkudas, Andreas
A1  - Kengelbach-Weigand, Annika
T1  - Comparison of hydrogels for the development of well-defined 3D cancer models of breast cancer and melanoma
JF  - Cancers
N2  - Bioprinting offers the opportunity to fabricate precise 3D tumor models to study tumor pathophysiology and progression. However, the choice of the bioink used is important. In this study, cell behavior was studied in three mechanically and biologically different hydrogels (alginate, alginate dialdehyde crosslinked with gelatin (ADA–GEL), and thiol-modified hyaluronan (HA-SH crosslinked with PEGDA)) with cells from breast cancer (MDA-MB-231 and MCF-7) and melanoma (Mel Im and MV3), by analyzing survival, growth, and the amount of metabolically active, living cells via WST-8 labeling. Material characteristics were analyzed by dynamic mechanical analysis. Cell lines revealed significantly increased cell numbers in low-percentage alginate and HA-SH from day 1 to 14, while only Mel Im also revealed an increase in ADA–GEL. MCF-7 showed a preference for 1% alginate. Melanoma cells tended to proliferate better in ADA–GEL and HA-SH than mammary carcinoma cells. In 1% alginate, breast cancer cells showed equally good proliferation compared to melanoma cell lines. A smaller area was colonized in high-percentage alginate-based hydrogels. Moreover, 3% alginate was the stiffest material, and 2.5% ADA–GEL was the softest material. The other hydrogels were in the same range in between. Therefore, cellular responses were not only stiffness-dependent. With 1% alginate and HA-SH, we identified matrices that enable proliferation of all tested tumor cell lines while maintaining expected tumor heterogeneity. By adapting hydrogels, differences could be accentuated. This opens up the possibility of understanding and analyzing tumor heterogeneity by biofabrication.
KW  - breast cancer
KW  - melanoma
KW  - biofabrication
KW  - hydrogel
KW  - tumor heterogeneity
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-211195
SN  - 2072-6694
VL  - 12
IS  - 8
ER  - 
TY  - JOUR
A1  - Jakubietz, Rafael G.
A1  - Jakubietz, Danni F.
A1  - Horch, Raymund E.
A1  - Gruenert, Joerg G.
A1  - Meffert, Rainer H.
A1  - Jakubietz, Michael G.
T1  - The microvascular peroneal artery perforator flap as a "lifeboat" for pedicled flaps
JF  - Plastic and Reconstructive Surgery – Global Open
N2  - Background:
Pedicled perforator flaps have expanded reconstructive options in extremity reconstruction. Despite preoperative mapping, intraoperative findings may require microvascular tissue transfer when no adequate perforators can be found. The free peroneal artery perforator flap may serve as a reliable back-up plan in small defects.

Methods:
In 16 patients with small soft tissue defects on the upper and lower extremities, perforator-based propeller flaps were planned. The handheld Doppler device was used to localize potential perforators for a propeller flap in close proximity to the defect. Perforators of the proximal peroneal artery were also marked to allow conversion to microvascular tissue transfer.

Results:
In 6 cases, no adequate perforators were found intraoperatively. In 4 patients, the peroneal artery perforator flap was harvested and transferred. The pedicle length did not exceed 4 cm. No flap loss occurred.

Conclusions:
When no adequate perforator capable of nourishing a propeller flap can be found intraoperatively, the free peroneal artery flap is a good option to reconstruct small soft tissue defects in the distal extremities. The short vascular pedicle is less ideal in cases with a large zone of injury requiring a more distant site of anastomosis or when recipient vessels are located in deeper tissue planes.
KW  - surgery
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-202233
VL  - 7
IS  - 9
ER  -