Adipose mesenchymal stem cells combined with platelet-rich plasma accelerate diabetic wound healing by modulating the Notch pathway

Background

Diabetic foot ulceration is a serious chronic complication of diabetes mellitus characterized by high disability, mortality, and morbidity. Platelet-rich plasma (PRP) has been widely used for diabetic wound healing due to its high content of growth factors. However, its application is limited due to the rapid degradation of growth factors. The present study aimed to evaluate the efficacy of combined adipose-derived mesenchymal stem cells (ADSCs) and PRP therapy in promoting diabetic wound healing in relation to the Notch signaling pathway.

Methods

Albino rats were allocated into 6 groups [control (unwounded), sham (wounded but non-diabetic), diabetic, PRP-treated, ADSC-treated, and PRP+ADSCs-treated groups]. The effect of individual and combined therapy was evaluated by assessing wound closure rate, epidermal thickness, dermal collagen, and angiogenesis. Moreover, gene and protein expression of key elements of the Notch signaling pathway (Notch1, Delta-like canonical Notch ligand 4 (DLL4), Hairy Enhancer of Split-1 (Hes1), Hey1, Jagged-1), gene expression of angiogenic marker (vascular endothelial growth factor and stromal cell-derived factor 1) and epidermal stem cells (EPSCs) related gene (ß1 Integrin) were assessed.

Results

Our data showed better wound healing of PRP+ADSCs compared to their individual use after 7 and 14 days as the combined therapy caused reepithelialization and granulation tissue formation with a marked increase in area percentage of collagen, epidermal thickness, and angiogenesis. Moreover, Notch signaling was significantly downregulated, and EPSC proliferation and recruitment were enhanced compared to other treated groups and diabetic groups.

Conclusions

These data demonstrated that PRP and ADSCs combined therapy significantly accelerated healing of diabetic wounds induced experimentally in rats via modulating the Notch pathway, promoting angiogenesis and EPSC proliferation.

Functional and Aesthetic Outcomes of Reconstruction of Soft-Tissue Defects of the Heel with Free Flap

Objective

To evaluate functional and aesthetic outcomes of the reconstruction of soft-tissue defects of the heel with microsurgical techniques using a free radial forearm flap and an anterolateral thigh flap.

Patients and methods

The study included 25 patients, 15 males and 10 females, with a mean age of 34.3 ± 10.4 years, with soft-tissue defects of the heel. Of them, 11 patients whose defects were of size between 5 and 10 cm in their largest dimension were treated using a free radial forearm flap, and 14 patients whose defects were of size larger than 10 cm in their largest dimension were treated using a free anterolateral thigh flap.Post-operatively, avoidance of weight-bearing and walking was required for 8 to 10 weeks. At the end of the follow-up, all patients underwent functional, aesthetic and sensation evaluation in addition to assessment of patient satisfaction.

Results

The median follow-up period was 24 months. The causes of the defect were trauma (14 patients), neuropathic ulcer (8 patients) and neoplasia (3 patients). The size of the defect ranged from 5 × 6 cm to 14 × 24 cm. Four patients had calcaneal fracture. By the end of the follow-up period, 21 cases showed complete success, whereas 2 flaps failed, one in each flap type, and the remaining two flaps showed partial loss of the edges (anterolateral thigh flaps). Failure was due to venous congestion (one patient) and ischaemia (one patient). Eighteen patients were satisfied with their aesthetic appearance, functional outcome and flap sensation.

Conclusion

Reconstruction of large heel defects, using radial forearm and anterolateral thigh free flaps, provides acceptable functional and aesthetic outcomes.

Functional Recellularization of Acellular Rat Liver Scaffold by Induced Pluripotent Stem Cells: Molecular Evidence for Wnt/B-Catenin Upregulation

BACKGROUND

Liver transplantation remains the only viable therapy for liver failure but has a severely restricted utility. Here, we aimed to decellularize rat livers to form acellular 3D bio-scaffolds suitable for seeding with induced pluripotent cells (iPSCs) as a tool to investigate the role of Wnt/β-catenin signaling in liver development and generation.

METHODS

Dissected rat livers were randomly divided into three groups: I (control); II (decellularized scaffolds) and III (recellularized scaffolds). Liver decellularization was established via an adapted perfusion procedure and assessed through the measurement of extracellular matrix (ECM) proteins and DNA content. Liver recellularization was assessed through histological examination and measurement of transcript levels of Wnt/β-catenin pathway, hepatogenesis, liver-specific microRNAs and growth factors essential for liver development. Adult rat liver decellularization was confirmed by the maintenance of ECM proteins and persistence of growth factors essential for liver regeneration.

RESULTS

iPSCs seeded rat decellularized livers displayed upregulated transcript expression of Wnt/β-catenin pathway-related, growth factors, and liver specification genes. Further, recellularized livers displayed restored liver-specific functions including albumin secretion and urea synthesis.

CONCLUSION

This establishes proof-of-principle for the generation of three-dimensional liver organ scaffolds as grafts and functional re-establishment.

The utility and outcomes of the temporalis muscle flap for palate reconstruction after maxillectomy for malignancy

BACK GROUND

A common pedicled facial technique in head and neck reconstruction is the TMF It can be utilised to replace missing tissues in a variety of conditions, including oral deformities of the hard and soft palate.

AIM

Aim of the study was to document the utility and outcomes with the reconstruction of the palate using TM flaps following Maxillectomy For maxillary sinus malignancies.

METHODOLOGY

The study included 24 patients who were operated on for cancer maxilla and eligible for maxillectomy and reconstruction of the Palate using temporalis flap. Follow-up was planned for at least 12 months postoperative. Postoperative physical and speech therapy are initiated to help improve speech and swallow outcomes and to prevent trismus.

RESULTS

The current study included 24 cases with Maxillary sinus cancer with a mean age of 42.34 ± 4.67. The mean operative time was 5.4 ± 1.22 h with no reported intraoperative bleeding or injury of important structures. No cases of facial palsy or trismus were reported while partial flap loss was reported in one case where oronasal fistula was evident. The donor site complications were minimal where seroma occurred in two patients and alopecia, wound infection and dehiscence were reported in one case each. The donor site depression was evident in 25 % of cases.

CONCLUSION

TMF is an excellent option for the reconstruction of many craniofacial defects, it is easy to be harvested with good blood supply with minimal postoperative complications.