Skin Expansion Research Articles

Primary management of the inframammary fold in breast reconstruction using the thoracoabdominal advancement flap: Surgical technique

Our experience in breast reconstruction confirms the significant importance of reconstructing the inframammary fold in achieving overall aesthetic satisfaction. We describe our technique for primary fixation of the inframammary fold in breast reconstruction using a thoracoabdominal advancement flap. This technique is suitable for patients with a vertical skin laxity of at least 5cm in the future inframammary fold. Prior to the procedure, it requires preparation through physiotherapy, the use of adhesive external breast prosthesis, and skin expansion using an inflatable prosthesis in extreme cases. The surgical approach follows the existing mastectomy scar. After subfascial dissection of the thoracoabdominal advancement flap, the surgeon proceeds to create two separate rows of sutures. The first row mimics the deep attachment of the inframammary fold, fixing the superficial fascia of the flap to the rib periosteum. The second row mimics the superficial attachment of the inframammary fold, fixing the dermis of the flap to the rib periosteum. The main advantage of this technique is its applicability to all breast reconstruction programs.

An Overview of Scaffolds and Biomaterials for Skin Expansion and Soft Tissue Regeneration: Insights on Zinc and Magnesium as New Potential Key Elements.

The utilization of materials in medical implants, serving as substitutes for non-functional biological structures, supporting damaged tissues, or reinforcing active organs, holds significant importance in modern healthcare, positively impacting the quality of life for millions of individuals worldwide. However, certain implants may only be required temporarily to aid in the healing process of diseased or injured tissues and tissue expansion. Biodegradable metals, including zinc (Zn), magnesium (Mg), iron, and others, present a new paradigm in the realm of implant materials. Ongoing research focuses on developing optimized materials that meet medical standards, encompassing controllable corrosion rates, sustained mechanical stability, and favorable biocompatibility. Achieving these objectives involves refining alloy compositions and tailoring processing techniques to carefully control microstructures and mechanical properties. Among the materials under investigation, Mg- and Zn-based biodegradable materials and their alloys demonstrate the ability to provide necessary support during tissue regeneration while gradually degrading over time. Furthermore, as essential elements in the human body, Mg and Zn offer additional benefits, including promoting wound healing, facilitating cell growth, and participating in gene generation while interacting with various vital biological functions. This review provides an overview of the physiological function and significance for human health of Mg and Zn and their usage as implants in tissue regeneration using tissue scaffolds. The scaffold qualities, such as biodegradation, mechanical characteristics, and biocompatibility, are also discussed.

Customization of Soft Tissue Expanders: Improving Safety, Accuracy, and Efficiency for Treatment of Large and Complicated Skin Lesions.

Soft tissue expansion is a common technique for restoring large skin defects. Fixed-type expanders may be inappropriate for the following reasons: (1) the shapes and sizes of the defects vary in different patients; and (2) the bulged base of the fixed-type expander does not fit the curve of the human body, which may induce complications such as concave deformities or nerve palsy from continuous mechanical compression. The customized expander adjusts better to the shape and the topography of the expansion site compared with the fixed-type expander. It improves expansion efficiency and reduces complications caused by compression. Between 2016 and 2022, customized soft tissue expansion was performed in 38 patients with skin lesions, including giant congenital melanocytic nevi and postburn scars. This series of patients included patients with a specific donor site shape that is unsuitable for fixed-type expanders. An expander was customized according to the shape of the donor site and then implanted in the subcutaneous pocket. After the expander reached a sufficient volume, the expander was removed, and the extra expanded skin flap was transferred to resurface the skin lesion. In the follow-up, the outcome and the complications were recorded. All the customized expanders fit not only the dimension but also the topography of the donor site. During expansion, 2 patients experienced leakage of the expander, and 3 patients suffered a skin rupture. In the remaining 33 patients, the expansion was successfully completed, and the expanded flaps restored the skin lesions as designed. The color and texture of the skin flaps remained satisfactory after long-term follow-up. Unlike fixed-type expanders, our customized expanders make it possible for "accurate" expansion, irrespective of the dimension and topography of the donor area. Customization of the expander helps increase efficiency and reduce complications caused by undue compression.

Clinical applications of skin traction technique with adjustable tension in treatment of large area skin defects

ObjectiveTo explore the clinical applications of the adjustable skin traction technique in the treatment of large area skin defects.Research designA prospective study.BackgroundThe skin is the largest organ of the human body and skin tissue exposed to external environment which makes it vulnerable to damage. There are many reasons for skin defects such as trauma, infection, burns, scars, tumors resection, inflammation, pigmented nevus, etc. Skin traction is the application of pulling force to the trunk or extremities for immobilization, fracture reduction and deformity correction. This technique accurately controls skin expansion which is safe, convenient and accelerates wound healing.MethodsA prospective study was conducted on 80 patients suffered from large area skin defects in the department of orthopedics, the first affiliated hospital of Zhengzhou University from September 2019 to January 2023. There were 40 patients in the experimental group who underwent skin traction. In contrast, 40 people in the control group underwent skin flaps or skin grafts without skin traction. The inclusion criteria include large area skin defects, normal peripheral skin & blood supply, normal vital organs, no severe coagulation dysfunction etc. Male & female with and without skin traction are 22 & 18 and 25 & 15 respectively. The skin traction device used was a hook and single rod type. The skin defect area was approximately 15 cm × 9-43 cm × 10 cm.ResultsPostoperatively, the experimental group with traction showed 2 cases of skin infection, 1 case of skin necrosis and 3 cases of inflammation recurrence. In contrast, the control group without traction showed 8 cases of skin infection, 6 cases of skin necrosis and 10 cases of inflammation recurrence. Skin infection (P = 0.04), skin necrosis (P = 0.02) and inflammatory response (P = 0.03) represented significant differences between two groups. There was also a significant difference in hospitalization costs (P = 0.001).ConclusionSkin traction has huge clinical applications including a shorter hospital stay, faster wound healing, lower hospitalization cost, high satisfaction rate, and a fair skin appearance after surgery. It is an effective method of treating skin and musculoskeletal defects.

Utilization of intense pulsed light for hair removal in pediatric auricular reconstruction using tissue expander: A retrospective cohort study.

This study aimed to investigate the safety and efficacy of depilation with intense pulsed light (IPL) in congenital microtia patients during their reconstruction treatment. The hairy skin was treated with the M22TM system (Lumenis, German) using a filter of 695 to 1200 mm. A contact prob with a window of 15 cm × 35 mm or 8 cm × 15 mm was used at a radiant setting of 14 to 15 J/cm2 in the non-expander group and 13 to 14 J/cm2 in the expander group, both in a single pulse mode. The efficiency index of hair removal was classified based on the percentage of hair density reduction as excellent (>75%), good (50-75%), fair (25-50%), poor (<25%). The depilation effect was compared between the 2 groups, and any adverse effects were evaluated. A total of 159 patients were included, with 93 patients in the expander group and 66 in the non-expander group. The reduction of the hair density in the expander group after 3 treatments was higher than that in the non-expander group [82.98 (73.47-89.09)% vs 77.84 (71.50-85.34)%; P < .05, Wilcoxon rank-sum test], as well as the efficiency [excellent cases 68 (73.12%) vs 37 (56.06%); P < .05, Chi-square test]. Four cases of folliculitis, 3 cases of blisters, and no instance of expander exposure and cartilage absorption were observed in this study. Hair removal with IPL is a safe and effective photo-epilation method during all stages of ear reconstruction using tissue expander. Depilation in the skin expansion period resulted in better outcomes after 3 treatments, although after 5 treatments no difference between the 2 groups was observed.

A series of nine newly developed techniques in CT-guided percutaneous lung biopsyPreliminary results from a prospective study.

e21023 Background: CT-guided percutaneous lung biopsy is important for the diagnosis of lung cancer especially in the area of precision medicine. In ASCO 2015, we reported that "Liquid withdraw" technique (to inject small amount of liquid while withdraw of the needle) can prominently reduce incidence of pneumothorax when combined with co-axial technigue in 38 cases. In ASCO 2017, we retrospectively studied 90 patients undergoing CT-guided percutaneous lung biopsy to investigate the role of this technigue in reducing complications and promoting biopsy effectiveness. Based on the above studies, we conducted a prospective study to further evaluate the role of this technique in conjunction with the other eight techniques (Position compensation, Cushion for position adjustment, Skin expansion in advance, Secondary location outside the pleura, Needle core instantaneous replacement, Mutual fix, Simultaneous bleeding arrest, and Cortical displacement) in the precision diagnosis and treatment of lung cancer. Methods: From January 16th, 2018 to October 11th, 2021, a total of 150 CT-guided percutaneous transthoracic biopsy procedures performed in 146 patients were prospectively evaluated. The pathologies and complications secondary to biopsy procedure were analyzed. Pneumothorax and bleeding was graded as mild/very mild, moderate, and severe. All patients were divided into two groups: the lesion depth was &lt; 30mm from the pleura and ≥30mm from pleura. Different complications between the two groups were analyzed using Pearson’s Chi-squared test for categorical values. Results: 148 cases was diagnosed out of 150 biopsies (98.67%), of which 118 cases were malignant (108 cases can be identified which type and source (91.53%), in which 68 cases were adenocarcinoma), 30 cases were benign. Pneumothorax occurred in 27 (18%) cases, among which, 12% were very mild pneumothorax and 6% were mild to moderate pneumothorax. 44 cases (29.33%) happened bleeding, among which, 21.33% could be classified as very mild, while 8% could be classified as mild to moderate. No infection, tumor implantation or aeroembolism observed. There were no statistically significant differences in the incidence of pneumothorax and bleeding at different distances from the pleura( &lt; 30mm vs ≥30mm, P＞0.05). Conclusions: This series of new techniques in CT-guided percutaneous lung biopsy significantly reduced the incidence of pneumothorax and bleeding and were preliminarily proved that can facilitate acquiring more tumor tissue for molecular testing and re-biopsy of lung cancer. Clinical trial information: ChiCTR1800017958 .

Tracing the Change and Contribution of Subcutaneous Adipose to Skin Expansion Using a Luciferase-Transgenic Fat Transplantation Model.

During skin expansion, subcutaneous adipose tissue undergoes the greatest change. The adipose layer appears to gradually thin or even disappear in long-term expansion. The response and contribution of adipose tissue to skin expansion remain to be elucidated. The authors established a novel expansion model by transplanting luciferase-transgenic adipose tissue into the rat dorsum, followed by integrated expansion, to trace the dynamic changes in subcutaneous adipose tissue during expansion and the migration of adipose tissue-derived cells. In vivo luminescent imaging was performed to continuously track the adipose tissue changes. Histologic analysis and immunohistochemical staining evaluated the regeneration and vascularization of the expanded skin. Growth factor expression in expanded skin with or without adipose tissue was determined to evaluate the paracrine effect of adipose tissue. Adipose tissue-derived cells were traced in vitro by anti-luciferase staining, and their fate was determined by costaining for PDGFRα, DLK1, and CD31. In vivo bioimaging showed that cells in adipose tissue were alive during expansion. After expansion, the adipose tissue exhibited fibrotic-like structures, with more DLK1 + preadipocytes. Skin expanded with adipose tissue was significantly thicker than that without adipose tissue, with more blood vessels and cell proliferation. Vascular endothelial growth factor, epidermal growth factor, and basic fibroblast growth factor expression was higher in adipose tissue than in skin, indicating paracrine support from adipose tissue. Luciferase-positive adipose tissue-derived cells were observed in expanded skin, indicating direct participation in skin regeneration. Adipose tissue transplantation can effectively promote long-term skin expansion by contributing to vascularization and cell proliferation by means of various mechanisms. The authors' findings suggest that it would be better if the expander pocket is dissected over the superficial fascia to preserve a layer of adipose tissue with skin. In addition, their findings support the treatment of fat grafting when expanded skin presents with thinning.

The SHH-GLI1 pathway is required in skin expansion and angiogenesis.

To investigate the role of GLI1 on skin proliferation and neovascularization during skin expansion in mice. We constructed GLI1-cre/R26-Tdtomato and GLI1-cre/R26-mtmg gene-tagged skin expansion mouse models. Using a two-photon in vivo imaging instrument to observe the changes in the number and distribution of GLI1(+) cells during the expansion process and to clarify the spatial relationship between GLI1(+) cells and blood vessels during the expansion process. In vitro proliferation assays were performed to further validate the effects of SHH (sonic hedgehog) and its downstream component GLI1 on cell proliferation viability. Finally, qRT-PCR was used to verify the changes in proliferation, angiogenesis-related factors, SHH signalling pathway-related factors, and the role of GLI1 cells in the process of skin expansion in mice. The number of GLI1(+) cells increased during dilation and were attached to the outer membrane of the vessel. The epidermis was thickened and the dermis thinned after the dilated skin was taken, while the epidermal thickening was suppressed and the dermis became thinner after the GLI1 cells were inhibited. The non-inhibited group showed a significant increase in PCNA positivity with prolonged dilation compared to the GANT61(GLI specificity inhibitor) inhibited group; CD31 immunofluorescence showed a significant increase in the number of dilated skin vessels and a significant decrease in the number of vessels after treatment with GANT61 inhibitor. In vitro proliferation results showed that SHH signalling activator significantly increased the proliferation viability of GLI1(+) hair follicle mesenchymal stem cells, while GNAT61 significantly inhibited the proliferation viability of GLI1(+) hair follicle mesenchymal stem cells. GLI1 is necessary for proliferation and neovascularization in expansion skin of mice through activation of the SHH signalling pathway.

Skin Expander to Enhance Anterior Coverage in Knee Liberation Surgery One Case Report

A female 11 years old, right knee stiffness since childhood. Able walking, but unable running, difficult sitting. Right knee Range of Motion 0-0-3°. Thigh muscle atrophy 2cm. Right lower limb axes well aligned. Rectus femoris muscle very tense, easy to feel under skin. Patella alta, 3 cm above normal position. Skin of anterior knee is in normality, but predictorily when flexion 120°, skin closure is impossible. Nerves and vessels are in normal condition. MRI shows severe contracture of Rectus Femoris. Vastus intermedius, lateralis and medialis are almost normal. Few adhesions inside the joint. Patellofemoral articulation smooth. First operation: placing a 300ml skin expander at prepatellar space, then inflate 300ml water by 10 times. Second operation: remove skin expander, lengthening Rectus Femoris 6 cm. Knee flexion 130°.Easy skin closure. 28th postoperative day, closed manipulation was performed under general anesthesia to achieve knee flexion 130°, then knee kept flexed for 2 hours. Knee flexion-extension was crucial exercise in longterm physical therapy. Last examination at 8th month postoperatively: almost normal walking, slight running, Knee Range of Motion 0-0-115°. By this case, presumable conclusion is skin expander may enhance the anterior coverage for the patients in knee liberation surgery

Subcutaneous Implantation of Unidirectional Self-Inflating Anisotropic Tissue Expander Has No Effect on the Physiological Parameters and Behaviours of Horses

The tissue expansion technique is one of the most important innovations in skin reconstructive surgery in human and veterinary medicine. This study investigated horses’ physiological and behavioural responses to subcutaneous implantation of a unidirectional self-inflating anisotropic tissue expander. The tissue expanders were subcutaneously implanted on six horses at three different locations: the frontal region of the head, the lateral side of the right shoulder, and the dorsomedial part of the cannon region of the right forelimb. Prior to the tissue expander implantation, each horse was clinically examined, and the observed vital parameters and behaviour were recorded as baseline data. For six days post implantations, the horses were clinically examined, implantation sites monitored, and the horse’s behaviour was recorded both during the day by visual observation and at night with a video camera. The results showed that all horses tolerated the subcutaneous gradual skin expansion by implantation of the tissue expanders, and all surgical sites healed without any complications. The implantation of the tissue expanders does not affect the vital parameters or overall horse behaviour either during the day or at night. In conclusion, the subcutaneous implantation of unidirectional anisotropic tissue expanders in horses resulted in successful skin growth with no physiological and psychological discomfort; hence skin expansion is a good option to be considered when pursuing equine skin reconstructive surgery.

Reverse Expansion for Breast Reconstruction after Skin-sparing and Nipple-sparing Mastectomy: Our First 100 Cases.

From January 2010 to September 2018, 253 breast reconstruction procedures were performed on 100 patients. The reverse expansion technique consists of autologous fat tissue transplantation requiring the combined use of a skin expander and of multiple lipofilling sessions. At the beginning of every session the breast expander was deflated by removing a saline volume similar to that of the fat to be injected. Overall, 56 breast reconstructions after skin-sparing mastectomy and 44 after nipple-sparing mastectomy were performed. An average of 661.5 cm3 of fat per session was harvested and an average of 305.3 cm3 per breast was injected. The average number of sessions to achieve breast reconstruction was 2.53. Only four complications after 253 procedures (1.5%) were reported: one donor site hemorrhage due to genetic lack of coagulation factors, and three surgical site infections. Considering the large number of positive factors such as a fast postoperative recovery, an easy learning curve, a lack of need of a specialized surgical team, a natural look of the breast shape, and the soft consistency of the grafted tissue, we believe this technique could be the first choice for autologous reconstruction after skin-sparing mastectomy and nipple-sparing mastectomy.

The Role of Tissue Expanders in the Reconstruction of Proximal Hypospadias

OBJECTIVETo report the technique and outcomes of tissue expansion (TE) for generating additional penile skin for urethroplasty and/or skin coverage during primary or redo hypospadias repair in penoscrotal transposition (PST) patients with a proximal hypospadias. METHODSProximal hypospadias and PST patients with a lack of penile skin, congenitally or after failed repair, who underwent TE assisted reconstruction were reviewed. TE were placed under the penile shaft and expanded skin was used for tubularized incised plate repair. Success was defined as urethral advancement to the corona or more distal with tension free skin coverage. RESULTSA total of 24 patients underwent reconstruction including 16 as part of primary repair and for redo repairs in 8. Nine patients experienced expander extrusion and posturethroplasty complications occurred in 43.8% of primary repairs and 75.0% of redo repairs; a urethrocutaneous fistula was most common (n = 8). Overall, success was achieved in 87.5% of patients with postoperative meatal locations almost all coronal (45.8%) or glanular (50.0%). CONCLUSIONProximal hypospadias reconstruction is challenging, and complications are not infrequent. TE is a useful alternative for complex patients with a skin paucity such that cutaneous coverage would be difficult following urethroplasty. Although the complication rate was 43.8% for primary repair, TE generated sufficient residual skin for success after additional reconstruction. For redo repair early use is most beneficial as there is more expandable skin. The pseudocapsules provide vascularized coverage to reinforce the urethra while there is sufficient skin to minimize the need for a skin graft for penile coverage.

Macrophage contribution to the survival of transferred expanded skin flap through angiogenesis.

Despite the application of tissue expansion in the reconstruction of significant tissue defects, complications with expanded random-pattern skin flaps remain a major challenge. Insufficient angiogenesis is one of the keys factors in flap ischemia and dysfunction. Macrophages play a key role in promoting tissue angiogenesis, but their effects on expanded flap angiogenesis and the survival of the transferred skin flap are still unknown. A rat scalp expansion model was established to evaluate the dynamic changes of macrophages in expanded skin. Clodronate liposomes (Clo-lipo) were injected into the expanded scalps to deplete the macrophages, and the expanded scalp flaps with macrophage depletion were orthotopically transferred. The remaining expanded rat scalp flaps were treated with either a macrophage-colony stimulating factor (M-CSF) alone or M-CSF in combination with Clo-lipo and transferred. The number of macrophages, blood perfusion, microvascular densities (MVDs), flap survival, histological changes, and gene expression related to macrophage polarization and angiogenesis were determined with immunofluorescence (IF) staining, full-field laser perfusion imager, hematoxylin and eosin (HE) staining, and quantitative real-time polymerase chain reaction. The number of pan-macrophages significantly increased in the expanded scalp on days 14 and 21 after expander placement. The depletion rate after treatment with Clo-lipo was 29.06%, and the number of macrophages was significantly reduced in the group that underwent Clo-lipo treatment on day 14 before flap transfer (P<0.05). Macrophage depletion resulted in decreased blood perfusion, reduced MVDs, lower expression of factors, and poor survival rate. The recruitment of macrophages with a M-CSF led to higher blood perfusion, increased MVDs, greater expression of angiogenic factors, and better flap survival after flap transfer. Alternatively activated macrophages in the expanded flap could significantly promote angiogenesis, improve blood perfusion, and ultimately increase the flap survival rate. Modulating alternatively activated macrophages may provide a key therapeutic strategy to promote expanded skin flap survival. Our study has provided a basis for clinically improving random-pattern skin flap survival.

Three dimensional printed wound dressings: recent progresses.

Three dimensional printed wound dressings: recent progresses.

A prospective study on the expansion rule of the directional skin and soft tissue expander in abdominal scar reconstruction

A prospective study on the expansion rule of the directional skin and soft tissue expander in abdominal scar reconstruction

Total Breast Reconstruction with Lipofilling after Traditional Mastectomy without the Use of Tissue Expanders.

Lipofilling can be used to reconstruct a breast without additional implants or autologous composite grafts. However, methods to maximize retention of the transferred fat remain under debate. Here, the authors present their experience of breast reconstruction with lipofilling without concomitant use of tissue expanders. Patients who had completed breast reconstruction with lipofilling between June of 2010 and June of 2016 were reviewed. Those with obtainable follow-up magnetic resonance imaging scans were included in this cross-sectional study. The hospital records were reviewed for details of the lipofilling operations. Magnetic resonance imaging scans were evaluated for the volume retention and quality of the transferred fat. The patients were asked to assess the appearance and sensitivity of the reconstructed breast, the recovery time, and any adverse effects at the fat donor area. Thirty-eight women with 41 reconstructed breasts were included in the study. The median age at follow-up was 62 years (range, 48 to 78 years). They had undergone a median of four (range, two to six) lipofilling procedures with a median total volume 690 mL (range, 369 to 1350 mL). After a median follow-up of 2.1 years (range, 0.4 to 6.8 years), the median proportion of transferred fat retained was 58% (range, 14% to 119%), representing a reconstructed breast volume of 76% (range, 17% to 100%) of the contralateral breast. Oil cysts larger than 10 mm were detected in 7%. Most patients reported being satisfied with the reconstructed breast and experienced few side effects. Breast reconstruction with lipofilling can be performed with an acceptable number of procedures and no preoperative skin expansion. It extends the option of autologous breast reconstruction to women unsuited for major reconstructive procedures. Therapeutic, IV.

Testing the circulation of expanded flaps-prevention of necrosis of expanded flaps (a clinic study).

Expanded flaps are commonly used in plastic surgery. Although expanded flaps are more resistant to hypoxia than unexpanded flaps, flap necrosis can sometimes occur, particularly with skin incisions of regular proportion. Distal skin necrosis of the expansion flap can be avoided by careful design; however, the utilization rate of the expansion flap decreases. Consequently, successfully avoiding distal skin flap necrosis remains a challenge. In this study, we designed a device for testing the circulation of the expanded flap that can decrease the risk of expanded flap necrosis, thus maximizing the use of an expanded flap. A total of 128 patients who underwent surgical repair between 2011 and 2019 and were retrospectively examined with the device for testing the circulation of the expanded flap were included in the study. The procedure included (1) making a device for testing the circulation, (2) implanting a skin expander, (3) injecting normal saline into the skin expander, (4) testing the circulation of the expanded flap, and (5) transferring the expanded flap to repair the defect. One hundred forty-eight expanded flaps were implanted in 128 patients. The expanded flap that was transferred to repair the defect had no necrosis or infection. None of the expanded flaps with separated blood supply, which could be observed during operations, revealed complications. The survival rates of the expanded flap were increased by testing the circulation of the expanded flap. Expanded flaps designed by this method showed no swelling or paleness and no obvious temperature changes. In addition, the length-to-width ratio could be extended to 3:1. Our proposed method resulted in an effective surgical procedure for the repair of tissue defects. This approach could effectively change the direction of the blood vessel of the expanded skin flap and prevent necrosis of the expanded flap, thus representing a practical way to increase the use of expanded flaps and the flap survival rate, making the whole expanded flap transfer procedure more convenient.

S100 calcium-binding protein A9 promotes skin regeneration through toll-like receptor 4 during tissue expansion.

In plastic surgery, tissue expansion is widely used for repairing skin defects. However, low expansion efficiency and skin rupture caused by thin, expanded skin remain significant challenges in promoting skin regeneration during expansion. S100 calcium-binding protein A9 (S100A9) is essential in promoting wound healing; however, its effects on skin regeneration during tissue expansion remain unclear. The aim of the present study was to explore the role of S100A9 in skin regeneration, particularly collagen production to investigate its importance in skin regeneration during tissue expansion. The expression and distribution of S100A9 and its receptors-toll-like receptor 4 (TLR-4) and receptor for advanced glycation end products were studied in expanded skin. These characteristics were investigated in skin samples of rats and patients. Moreover, the expression of S100A9 was investigated in stretched keratinocytes in vitro. The effects of S100A9 on the proliferation and migration of skin fibroblasts were also observed. TAK-242 was used to inhibit the binding of S100A9 to TLR-4; the levels of collagen I (COL I), transforming growth factor beta (TGF-β), TLR-4 and phospho-extracellular signal-related kinase 1/2 (p-ERK1/2) in fibroblasts were determined. Furthermore, fibroblasts were co-cultured with stretched S100A9-knockout keratinocytes by siRNA transfection and the levels of COL I, TGF-β, TLR-4 and p-ERK1/2 in fibroblasts were investigated. Additionally, the area of expanded skin, thickness of the dermis, and synthesis of COL I, TGF-β, TLR-4 and p-ERK1/2 were analysed to determine the effects of S100A9 on expanded skin. Increased expression of S100A9 and TLR-4 was associated with decreased extracellular matrix (ECM) in the expanded dermis. Furthermore, S100A9 facilitated the proliferation and migration of human skin fibroblasts as well as the expression of COL I and TGF-β in fibroblasts via the TLR-4/ERK1/2 pathway. We found that mechanical stretch-induced S100A9 expression and secretion of keratinocytes stimulated COL I, TGF-β, TLR-4 and p-ERK1/2 expression in skin fibroblasts. Recombined S100A9 protein aided expanded skin regeneration and rescued dermal thinning in rats in vivo as well as increasing ECM deposition during expansion. These findings demonstrate that mechanical stretch promoted expanded skin regeneration by upregulating S100A9 expression. Our study laid the foundation for clinically improving tissue expansion using S100A9.

Effects of mechanical forces on the formation of cutaneous wounds during skin expansion and emerging therapies for wound healing and scar prevention.

To update a possible role of cosmeceutical topic treatment to obtain a better scar. This is a preliminary supportive study. A total of 14 patients who went to the General Hospital of Mexico City, Mexico, between May and December 2020, for breast reconstruction were included in the current study. The biopsies were carried out to the scar area of the previous I° and II° surgery. The patients were thus divided into 2 groups: those who used Cicolea cream® as a treatment supplement and those who used only petrolatum. Collagen fibers arranged in a regular pattern in the group treated with Cicolea compared to dispersed collagen fibers in the group treated with pure petrolatum. Furthermore, the patients who presented hypertrophic or keloid scars secondary to mastectomy, developed after insertion of breast expanders an organized scarring process, with improvement of scar if treated with Cicolea. Based on our observations, it is possible to propose that the action of the polyphenols present in the different components of Cicolea® cream leads to a better evolution of the wound healing compared to the action of petrolatum composition.

Skin Expansion Technology in Acute Burns and Chronic Wounds.

The ability to grow skin has long been a topic of study and therapeutic interest. Currently, the main ways of doing this are 1) by placing tissue-expansion devices in the subcutaneous space and expanding skin over time, which can then be moved to cover contiguous structures, and 2) via processes that require relatively long (30 days) incubation periods to grow the patient's autogenous skin into laminar sheets. Over the past five years, there have been significant developments in the ability to expand skin cells, either at the bedside or in the laboratory, but much more rapidly than with previous methods. We explore and discuss the current skin cell-expansion techniques, focusing on point-of-care therapeutic interventions that can be used in the burn population as well as the chronic wound population, hair follicle stem-cell incubation techniques and studies supporting this therapy, as well as micro bullae grafting, and morcellated skin cell therapy. The current data supporting these therapeutic interventions and their current direction are outlined in detail.