{
  "abstract": "Background: Autologous buccal mucosa grafts remain the surgical standard for complex urethral stricture repair but are limited by donor-site morbidity, restricted tissue availability, and inadequate graft vascularization. Acellular scaffolds, whether synthetic or natural, can offer either mechanical or biological signals but not both. Hybrid composite scaffolds combining synthetic structural support with natural bioactive polymers have been proposed to address this limitation. In this work, a trilayer scaffold consisting of a poly(lactide-co-glycolide) (PLGA) core with chitosan on either side was assessed in vivo in a controlled rabbit dorsal onlay urethroplasty model.\n\nMethods: Twenty-four male New Zealand White rabbits were allocated 1:1:1 to dorsal onlay urethroplasty with the trilayer scaffold, a monolayer PLGA scaffold, or sham control, using weight-stratified allocation. The primary endpoint was vessel density on CD31-stained sections at 12 weeks; secondary endpoints included tissue thickness, fibrosis, smooth muscle content, re-epithelialization, inflammatory cell scores, and urethrography, assessed by blinded observers.\n\nResults: Vessel density in the trilayer was intermediate between sham (highest) and the monolayer (lowest), with significant overall between-group variation (p = 0.008); the trilayer did not significantly differ from the monolayer (p = 0.248). Macrophage scores showed a non-significant trend toward lower values in the trilayer than in the monolayer (p = 0.062), and multinucleated giant-cell scores were significantly higher in both scaffold groups than in sham (p = 0.026), consistent with a foreign-body response. Vessel density was inversely correlated with tissue thickness and fibrosis, defining a coherent host-response signature. Re-epithelialization was complete across groups without ulceration features on histological review. Retrograde urethrography demonstrated preserved patency in all 23 animals completing follow-up, with no ≥50% stricture observed.\n\nConclusion: The trilayer scaffold was feasible to implant and well tolerated in a rabbit dorsal onlay urethroplasty model, supporting tissue regeneration with preserved urethral patency. The trilayer did not significantly increase vessel density over the monolayer at 12 weeks, although a non-significant trend toward lower macrophage scores was observed in the trilayer group. These findings refine rather than confirm the development hypothesis and motivate future studies with earlier endpoints, mechanical-modulus tuning, and alternative polymer ratios.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Renal Surgery and Urology, Aalborg University Hospital , ,",
    "Materials Science and Engineering Group, Department of Materials and Production, Aalborg University , ,",
    "Department of Pathology, Aalborg University Hospital , ,",
    "Department of Clinical Medicine, Aalborg University , ,",
    "Global Andrology Forum, Global Andrology Foundation , , ,",
    "Department of Pediatric Urology, Sidra Medicine and Weill Cornell Medical College , ,",
    "Regenerative Medicine, Department of Health Science and Technology, Faculty of Medicine, Aalborg University , ,"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 13,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Marco Bassam Mahdi"
    },
    {
      "affs": [
        1
      ],
      "name": "Fatemeh Mohtaram"
    },
    {
      "affs": [
        0
      ],
      "name": "Rikke Nørresø Haase"
    },
    {
      "affs": [
        0
      ],
      "name": "Grazvydas Tuckus"
    },
    {
      "affs": [
        1
      ],
      "name": "Peter Fojan"
    },
    {
      "affs": [
        2
      ],
      "name": "Joar Bergman"
    },
    {
      "affs": [
        3
      ],
      "name": "Christian Thomsen"
    },
    {
      "affs": [
        3
      ],
      "name": "Benedict Kjærgaard"
    },
    {
      "affs": [
        3
      ],
      "name": "Sanne Ross Sørensen"
    },
    {
      "affs": [
        4
      ],
      "name": "Hiva Alipour"
    },
    {
      "affs": [
        5
      ],
      "name": "Tariq O. Abbas"
    },
    {
      "affs": [
        6
      ],
      "name": "Cristian Pablo Pennisi"
    },
    {
      "affs": [
        0
      ],
      "name": "Tommy Kjærgaard Nielsen"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8ad3g7g035z7t.bib",
  "cited_by": 0,
  "doi": "10.3389/fbioe.2026.1891449",
  "fulltext_url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13724350/?tool=EBI",
  "id": "8ad3g7g035z7t",
  "issns": [
    "2296-4185"
  ],
  "landing_url": "https://europepmc.org/article/PMC/PMC13724350",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Original Research"
    ],
    [
      "openalex",
      "2746|Tissue Engineering and Regenerative Medicine"
    ]
  ],
  "openalex": "W7222970496",
  "pdf_url": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13724350/pdf/?tool=EBI",
  "pmcid": "PMC13724350",
  "pmid": "42973649",
  "published": "2026-10-19",
  "publisher": "Frontiers Media SA",
  "ris": "https://research.draconitic.com/paper/8ad3g7g035z7t.ris",
  "sources": [
    {
      "first_seen": "2026-11-03T15:20:51Z",
      "native_id": "PMC:PMC13724350",
      "source": "europepmc",
      "url": "https://europepmc.org/article/PMC/PMC13724350"
    },
    {
      "first_seen": "2026-11-04T12:22:56Z",
      "native_id": "PMC13724350",
      "source": "pmc",
      "url": "https://doi.org/10.3389/fbioe.2026.1891449"
    },
    {
      "first_seen": "2026-11-04T15:20:48Z",
      "native_id": "MED:42973649",
      "source": "europepmc",
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    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2746|Tissue Engineering and Regenerative Medicine",
      "subfield": "surgery"
    }
  ],
  "title": "In vivo evaluation of a chitosan/PLGA/chitosan composite versus monolayer PLGA electrospun scaffold for dorsal onlay urethroplasty: a controlled study in rabbits",
  "title_text": "In vivo evaluation of a chitosan/PLGA/chitosan composite versus monolayer PLGA electrospun scaffold for dorsal onlay urethroplasty: a controlled study in rabbits",
  "type": "peer-reviewed",
  "updated_at": "2026-11-06T12:20:52Z",
  "url": "https://research.draconitic.com/paper/8ad3g7g035z7t",
  "venue": "Frontiers in bioengineering and biotechnology",
  "versions": []
}