Abstract. The islets of Langerhans is the endocrine function region of pancreas, which exist in five cell types. The majority of endocrine cells are insulin-secreting β cells, mixed up with glucagon-secreting α-cells. The islets of Langerhans are highly vascularized, and the capillary network around the islet is about five times denser than that in the exocrine tissues. It guarantees endocrine cells adequately contact with the capillary networks. Above mentioned is the basis of deep study the interaction between β cells and capillary. Increasing number of studies contribute to the consensus that endothelial cells have positive effects in the islet microenvironment. Endothelial cells can act as endocrine cells which release many active substances, such as hepatocyte growth factors (HGF), thrombospondin-1(TSP-1), laminins, and collagens by means of different molecule pathways, inducing β cells differentiation, proliferation, survivor, and insulin release next to the vessels. Apart from the effect of endothelial cells on β cells by paracrine fashion, the islets can utilize VEGF-A, angiopoietin-1 and insulin signaling to increase the interaction with endothelial cells. As the endocrine role of endothelial cells to β cells, it may be a novel target to stimulate β cells regeneration, promote vascularization post islet transplantation strategy in the treatment of diabetes mellitus.

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Background Large-scale maxillocervical scars impair face and neck function and damage appearance. The forehead expanded bilateral superficial temporal pedicled flap is a good treatment strategy for this area; however, the traditional cutaneous pedicled flap damages the temporal hair area. This impairs aesthetics and causes alopecia; furthermore, requires an additional pedicle-cut operation. Methods A retrospective study was performed on 7 patients with large-scale maxillocervical scars from January 2014 to August 2018. Forehead expanders were implanted in the first-stage operation for all patients. After the injection and rest period, patients were treated using the forehead expanded bilateral superficial temporal vascular fascial pedicled flap. Superficial temporal vascular fascia pedicles were carefully harvested. The use of an intralesional or hidden retrotragus incision was determined by the presence of a preauricular scar. Patient satisfaction with postoperative neck activity and the incision scar was evaluated. Results Intralesional and retrovagus incisions were used in 4 and 3 cases, respectively. One flap developed hematoma, which recovered completely after conservative treatment; all other cases had no complications. All flaps healed well. The neck mobility of the patients was significantly improved with no visible scar in the temporal region. Six cases reported being “very satisfied” and one was “relatively satisfied” with their improvement in neck mobility. All cases reported being “very satisfied” with frontotemporal morphology. Conclusions The forehead expanded bilateral superficial temporal vascular fascial pedicled flap is a good choice for patients with large-scale maxillocervical scars. This technique can maintain the aesthetics of temporal hair and reduce patients extra surgical injury.

Chest wall ulcer induced by postmastectomy radiation therapy (PRMT) remains challenging for plastic surgeons because of the reduced blood supply, fibrosis, and impaired cellular potential in the irradiated area. In this study, chest wall ulcer was treated with negative pressure wound therapy (NPWT) and the latissimus dorsi myocutaneous (LDM) flap reconstruction in 2 stages. A retrospective study was performed on consecutive patients with chronic radiation-induced ulcers in chest wall from June 2012 to June 2017. Surgical debridement and NPWT were performed in the first stage and the chest wall reconstructed by the LDM flap transplantation after extensive debridement in the second stage. There were 10 female patients with chest wall ulcers with a mean age of 60.3 years. The average duration of the ulcers was 21.2 months and the ulcers varied from 1 × 2 to 5 × 7 cm2. Histological examination denied any recurrent breast cancer or radiation-related malignancy. Negative pressure wound therapy was applied with 100 to 125 mm Hg negative pressure during a period of 5 to 7 days in the first stage. The LDM flap varied from 11 × 15 to 15 × 20 cm2. The mean follow-up was 25.9 months. All the flaps survived well with satisfactory appearance and there was no donor-site morbidity or ulcer recurrence during the follow-up period. The staged treatment of the chest wall radiation ulcer incorporated the benefits of NPWT and LDM flap. It is beneficial in increasing the blood and nutrient supply to the irradiated tissue, enhancing the debridement and promoting tissue healing, thus improving the flap survival and decreasing the ulcer recurrence.