Mechanical properties of PSIS and PADM.

<p>**<b><i>vs</i></b><b> PADM(</b><b><i>P</i></b><b><0.01).</b></p><p> <b>Psi = 6.895 Kpa.</b></p

Adhesion and thickness of scaffolds varied during 12 weeks.

<p>A and B) Adhesion tenacity and surface area of PSIS and PADM after implantation. C) The increase of the implant thickness after implantation.*<i>P</i><0.05 <i>vs.</i> PADM. **<i>P</i><0.01 <i>vs.</i> PADM.</p

Surface area of PSIS and PADM.

<p>Both PSIS and PADM showed significant contraction after implantation.</p

Contraction of the implants 12 weeks after implantation.

<p>The contraction of the implants surrounding the sutures (arrows) repairing the abdominal wall defects. A) PSIS implant. B) PADM implant. C) Contracted PSIS implant 12 weeks after implantation. D) Contracted PADM implant 12 weeks after implantation.</p

Histologic appearance of the PSIS and PADM explants (Masson trichrome staining and Immunostaining).

<p>A–D: Masson trichrome staining; E–F: Immunostaining. (A) PSIS at Week 1 (×100). Only a thin layer of disorganized collagen deposition was observed at the interface. (B) PADM at Week 1 (×100). Thinner, but more organized, collagen deposition was observed at the interface. (C) PSIS at Week 12 (×100). At the interface, the implants were significantly degraded and replaced by a thick layer of well-vascularized and organized fibrous connective tissue. (D) PADM at Week12 (×100). At the interface, the implants were replaced by well-organized collagen deposition similar to that seen for PSIS. (E) PSIS at Week 12 (×200). Active neovascularization was observed in the center of the scaffold. (L) PADM at Week 12 (×200). Fewer new blood vessels grew into the center of the PADM scaffold compared with the PSIS implants.</p

Histologic scoring criteria for microscopic examination.

<p>Histologic scoring criteria for microscopic examination.</p

Scaffolds structures by SEM.

<p>A) PSIS scaffold. B) PADM scaffold. C) SEM photographs showing PSIS, ×500 and D) PADM, ×500.</p

Histologic appearance of the PSIS and PADM explants (H & E staining).

<p>(A) PSIS at Week 1 (×100). Pronounced inflammatory cell infiltration and few newly formed blood vessels were observed at the interface between PSIS and the surrounding tissues. (B) PADM at Week 1 (×100). Less inflammatory cell infiltration and fewer newly formed blood vessels were observed at the interface between PADM and the surrounding tissues. (C) PSIS at Week 12 (×100). The inflammatory response diminished significantly, and a large amount of well-vascularized, fibrous connective tissue, was observed at the interface. (D) PADM at Week 12 (×100). A similar level of inflammatory response was observed, but with less vascularization at the interface compared with PSIS. Host incorporation (invasion of the implant by host fibroblasts and endothelial cells) was also observed. (E) PSIS at Week 12 (×200). Oriented bundles of collagenous connective tissue with abundant newly formed blood vessels were observed, with only a little PSIS remaining at the center of the scaffold site. (F) PADM at Week 12 (×200). Oriented bundles of collagenous connective tissue with some newly formed blood vessels were observed, with more PADM remaining at the center of the scaffold site.</p

Semiquantitative adhesion scoring system.

<p>Semiquantitative adhesion scoring system.</p

The strength of incorporation of the PSIS and PADM implants during the course of the experiment.

<p>The strength of incorporation of the PSIS and PADM implants during the course of the experiment.</p