Posttraumatic Scrotal Reconstruction with a Pedicled "Extended" Superficial Circumflex Iliac Artery Perforator Flap: A Case Report.

The superficial circumflex iliac artery (SCIA) perforator (SCIP) flap has been used for scrotal reconstruction after Fournier's gangrene, skin cancer, or infections. However, there are few publications with regard to penoscrotal reconstruction after a traumatic injury with this flap. In this article, we propose a new SCIP flap variation, the "extended" or "direct" SCIP flap, to effectively reconstruct a wide scrotal defect after a traumatic injury. The "extended" SCIP flap is designed medial and cranial to the anterosuperior iliac spine (ASIS) using the superficial branch of the SCIA as the main pedicle.

The onset of PI3K-related vascular malformations occurs during angiogenesis and is prevented by the AKT inhibitor miransertib.

Low-flow vascular malformations are congenital overgrowths composed of abnormal blood vessels potentially causing pain, bleeding and obstruction of different organs. These diseases are caused by oncogenic mutations in the endothelium, which result in overactivation of the PI3K/AKT pathway. Lack of robust in vivo preclinical data has prevented the development and translation into clinical trials of specific molecular therapies for these diseases. Here, we demonstrate that the Pik3caH1047R activating mutation in endothelial cells triggers a transcriptome rewiring that leads to enhanced cell proliferation. We describe a new reproducible preclinical in vivo model of PI3K-driven vascular malformations using the postnatal mouse retina. We show that active angiogenesis is required for the pathogenesis of vascular malformations caused by activating Pik3ca mutations. Using this model, we demonstrate that the AKT inhibitor miransertib both prevents and induces the regression of PI3K-driven vascular malformations. We confirmed the efficacy of miransertib in isolated human endothelial cells with genotypes spanning most of human low-flow vascular malformations.

RhoA/ROCK2 signalling is enhanced by PDGF-AA in fibro-adipogenic progenitor cells: implications for Duchenne muscular dystrophy.

BACKGROUND: The lack of dystrophin expression in Duchenne muscular dystrophy (DMD) induces muscle fibre and replacement by fibro-adipose tissue. Although the role of some growth factors in the process of fibrogenesis has been studied, pathways activated by PDGF-AA have not been described so far. Our aim was to study the molecular role of PDGF-AA in the fibrotic process of DMD. METHODS: Skeletal muscle fibro-adipogenic progenitor cells (FAPs) from three DMD treated with PDGF-AA at 50 ng/mL were analysed by quantitative mass spectrometry-based proteomics. Western-blot, immunofluorescence, and G-LISA were used to confirm the mass spectrometry results. We evaluated the effects of PDGF-AA on the activation of RhoA pathway using two inhibitors, C3-exoenzyme and fasudil. Cell proliferation and migration were determined by BrdU and migration assay. Actin reorganization and collagen synthesis were measured by phalloidin staining and Sircol assay, respectively. In an in vivo proof of concept study, we treated dba/2J-mdx mice with fasudil for 6 weeks. Muscle strength was assessed with the grip strength. Immunofluorescence and flow cytometry analyses were used to study fibrotic and inflammatory markers in muscle tissue. RESULTS: Mass spectrometry revealed that RhoA pathway proteins were up-regulated in treated compared with non-treated DMD FAPs (n = 3, mean age = 8 ± 1.15 years old). Validation of proteomic data showed that Arhgef2 expression was significantly increased in DMD muscles compared with healthy controls by a 7.7-fold increase (n = 2, mean age = 8 ± 1.14 years old). In vitro studies showed that RhoA/ROCK2 pathway was significantly activated by PDGF-AA (n = 3, 1.88-fold increase, P < 0.01) and both C3-exoenzyme and fasudil blocked that activation (n = 3, P < 0.05 and P < 0.001, respectively). The activation of RhoA pathway by PDGF-AA promoted a significant increase in proliferation and migration of FAPs (n = 3, P < 0.001), while C3-exoenzyme and fasudil inhibited FAPs proliferation at 72 h and migration at 48 and 72 h (n = 3, P < 0.001). In vivo studies showed that fasudil improved muscle function (n = 5 non-treated dba/2J-mdx and n = 6 treated dba/2J-mdx, 1.76-fold increase, P < 0.013), and histological studies demonstrated a 23% reduction of collagen-I expression area (n = 5 non-treated dba/2J-mdx and n = 6 treated dba/2J-mdx, P < 0.01). CONCLUSIONS: Our results suggest that PDGF-AA promotes the activation of RhoA pathway in FAPs from DMD patients. This pathway could be involved in FAPs activation promoting its proliferation, migration, and actin reorganization, which represents the beginning of the fibrotic process. The inhibition of RhoA pathway could be considered as a potential therapeutic target for muscle fibrosis in patients with muscular dystrophies.

Isolation of human fibroadipogenic progenitors and satellite cells from frozen muscle biopsies.

Skeletal muscle contains multiple cell types that work together to maintain tissue homeostasis. Among these, satellite cells (SC) and fibroadipogenic progenitors cells (FAPs) are the two main stem cell pools. Studies of these cells using animal models have shown the importance of interactions between these cells in repair of healthy muscle, and degeneration of dystrophic muscle. Due to the unavailability of fresh patient muscle biopsies, similar analysis of interactions between human FAPs and SCs is limited especially among the muscular dystrophy patients. To address this issue here we describe a method that allows the use of frozen human skeletal muscle biopsies to simultaneously isolate and grow SCs and FAPs from healthy or dystrophic patients. We show that while the purified SCs differentiate into mature myotubes, purified FAPs can differentiate into adipocytes or fibroblasts demonstrating their multipotency. We find that these FAPs can be immortalized and the immortalized FAPs (iFAPs) retain their multipotency. These approaches open the door for carrying out personalized analysis of patient FAPs and interactions with the SCs that lead to muscle loss.

The Effect of Perioperative Blood Transfusions on Microvascular Anastomoses.

INTRODUCTION: Perioperative transfusions are associated with complications of free flaps. The purpose of the present study was to find out whether there is a significant relationship between the risk of developing complications in vascular anastomoses and the history of transfusions. METHODS: We studied 372 patients retrospectively with microsurgical reconstruction between 2009 and 2017 with regards to the number of red blood cell concentrates transfused. Complications were analyzed relative to flap loss and complications in microvascular anastomoses. RESULTS: 130 patients (34.9%) received blood transfusions. Some 55% of them were transfused between the day of the intervention and the first postoperative day. Ninety-six patients were reoperated on (25.7%). Of those, thirty-six patients (37.5%) corresponded to anastomosis failure. The percentage of patients transfused among those who required reoperation was 55.2%. The percentage of patients transfused among those who were reoperated on within the first 72 h due to an alteration in the anastomosis was 60.6%, while it was 25.6% (Chi square P = 0.0001) for the rest of the patients. CONCLUSIONS: Although there is a strong association between transfusion and vascular anastomosis failure, it is not possible to establish the causation between the two.

Turbocharged bilateral pedicled DIEP flap for reconstruction of thigh defect without recipient vessels: A case report.

Reconstruction of thigh defects is usually straightforward, but in cases of poor soft tissue quality, free flap reconstruction is not possible due to the absence of recipient vessels. The turbocharge technique may increase the viable, vascularized area of a flap. In this report we present a case of the use of a turbocharged bilateral pedicled DIEP flap for reconstruction of thigh defect without recipient vessels. A 29-year-old woman who underwent neoadjuvant chemotherapy plus radiation therapy for a leiomyosarcoma on the left thigh. Six weeks later, complete tumor excision and a femoropopliteal bypass with contralateral saphenous vein was performed. In the following days the wound had dehiscence, infection, necrosis of the surrounding muscles and exposure of femoropopliteal bypass. No recipient vessels were available for free flap and critical limb ischemia due to bypass thrombosis was detected. The reconstruction of a large thigh defect (30 × 12 cm) and the coverage of a femoropopliteal bypass with a turbocharged bilateral pedicled DIEP flap was performed. A flap including the entire infraumbilical tissue was designed and the anastomosis of the proximal stump of the right inferior epigastric vessels with the distal ends of the inferior left epigastric vessels was performed to increase the viable area. The flap survived without any complications during the postoperative period. At 12-month follow up, coverage was stable with no tumor recurrence. Our result suggests that a turbocharged bilateral pedicled DIEP flap may be an option for reconstructing large tissue defects when no recipient vessels are available for free flap.