Roles of Mechanosensitive Channel Piezo1 in Wound Healing and Scar Formation.

The ability to heal one's wounds is perhaps one of the most fundamental and critical of physiologic processes. This coordinated and closely regulated sequential biological process involves a variety of migratory and resident cells. The activation, modulation, balance, and control of these functions depend upon soluble mediators that activate cells and modulate their diverse functions. Recent advances have identified mechanotransduction as functionally integral in many different cell types and physiologic processes. The mechanically sensitive ion channel Pieoz1 is expressed on platelets, neutrophils, macrophages, endothelial cells, keratinocytes, and fibroblasts, all of which are principally involved in wound healing. On a cellular level, there have been great advances in our understanding of the functional role of Piezo1 mechanotransduction in cutaneous wounding. The blocking of Piezo1 has recently been shown to reduce scarring in vivo and yet, thus far, a comprehensive understanding of the roles that Piezo1 plays in in vivo wound healing remains lacking. Recognizing the ever-present and critical importance of optimal and reparative wound healing, and with the availability of new physical mechanomodulating devices, the time is ripe for gaining deeper insights into optimizing wound healing. In this review, we describe the current knowledge of Piezo1 related to wound healing.

[Surgical management of burn injury patients : Comments on the guidelines on treatment of thermal injuries in adults]. / Chirurgisches Management des brandverletzten Patienten : Kommentar zur Leitlinie Behandlung thermischer Verletzungen des Erwachsenen.

The treatment of burn injury patients is a unique challenge for clinicians. The extent of thermal injuries ranges from very small burns to life-threatening burn injuries. Insufficient treatment can result in a substantial impairment in the quality of life. In order to avoid such sequelae a targeted treatment must be carried out. A precise diagnosis determines the necessary treatment. Superficial second-degree burns (2a) not involving the face, hand or joints with a total body surface area smaller than 10% can usually be treated with modern wound dressings in an outpatient setting. Deep second-degree burns (2b) are an indication for debridement. In addition to the classical surgical procedures with tangential excision, enzymatic debridement can also be employed. Similarly, indeterminate burns (2a/2b) are also considered to be an indication for enzymatic debridement. Third-degree burns are treated with early debridement and skin grafting. These patients can also benefit from special dermal replacement procedures for an improvement of the functional and esthetic results. Due to the long-term visible sequelae of burns, aftercare of these patients is indicated.

[Surgical management of burn injury patients : Comments on the guidelines on treatment of thermal injuries in adults]. / Chirurgisches Management des brandverletzten Patienten : Kommentar zur Leitlinie Behandlung thermischer Verletzungen des Erwachsenen.

The treatment of burn injury patients is a unique challenge for clinicians. The extent of thermal injuries ranges from very small burns to life-threatening burn injuries. Insufficient treatment can result in a substantial impairment in the quality of life. In order to avoid such sequelae a targeted treatment must be carried out. A precise diagnosis determines the necessary treatment. Superficial second-degree burns (2a) not involving the face, hand or joints with a total body surface area smaller than 10% can usually be treated with modern wound dressings in an outpatient setting. Deep second-degree burns (2b) are an indication for debridement. In addition to the classical surgical procedures with tangential excision, enzymatic debridement can also be employed. Similarly, indeterminate burns (2a/2b) are also considered to be an indication for enzymatic debridement. Third-degree burns are treated with early debridement and skin grafting. These patients can also benefit from special dermal replacement procedures for an improvement of the functional and esthetic results. Due to the long-term visible sequelae of burns, aftercare of these patients is indicated.

Reconstruction of Upper and Lower Limb Defects with Medial Sural Artery Perforator Flaps: Is Aesthetics Worth the Effort? A Retrospective Analysis.

Background One of the most essential goals in managing complex limb defects is obtaining adequate soft tissue coverage with excellent functional and aesthetic outcomes. Free perforator skin flaps represent an optimal option for such defects. Therefore, our intention was to reconstruct these kinds of defects with thin fasciocutaneous flaps without the need for debulking. Herein, we define the legitimate use of the medial sural artery perforator (MSAP) flaps for small-moderate size defect coverage of the hand and foot. Patients and Methods Seven patients received MSAP flaps for reconstruction of different hand and foot defects, of which the majority were males (4/7). Age, sex, flap size, location, number of perforators, recipient vessel, type of anastomosis, technique of donor site closure, and postoperative morbidity were recorded. Patients' age ranged from 48 to 84 years. Results Single-stage debridement followed by reconstruction was performed. Flap sizes ranged from 6 to 18 cm in length and 4 to 10 cm in width. The pedicles of 6 flaps were anastomosed to the tibial artery system (three posterior tibial artery, three dorsalis pedis artery) and one to the ulnar artery. Conclusion MSAP flap can be a versatile option for single-stage reconstruction of small-moderate size defects of the extremities, where thin, soft tissue envelope is required. This flap has lower donor site morbidity, more tedious elevation process, and has a good reconstructive and aesthetic result without the need for debulking in the future.

The periodontal ligament, temperature-sensitive ion channels TRPV1-4, and the mechanosensitive ion channels Piezo1 and 2: A Nobel connection.

Teeth are subject to a variety of mechanical forces and vectors. The periodontal ligament (PDL), fibrous tissue that connects the cementum of the tooth to the bony socket, plays a decisive role in transmitting force to alveolar bone via Sharpey fibers, transforming and converting these forces into biological signals. This interaction effects significant osteoblastic and osteoclastic responses via autocrine proliferative and paracrine responses. Recent discoveries of receptors for temperature and touch by the Nobel laureates David Julius and Ardem Patapoutian, respectively have a profound impact on orthodontics. Transient receptor vanilloid channel 1 (TRPV1), initially described as a receptor for temperature, has been proposed to participate in the sensing of force. TRPV4, another ion channel receptor, perceives tensile forces as well as thermal and chemical stimuli. Piezo1 and 2, the classic receptors for touch, in addition to the aforementioned receptors, have similarly been described on PDL-derived cells. In this text, we review the role of the temperature-sensitive ion channels and mechanosensitive ion channels on their biological function and influence in orthodontic treatment.

Autologous Fat Transfer for Thumb Carpometacarpal Joint Osteoarthritis: Long Term Results. / Eigenfettinjektion bei Rhizarthrose: 5 Jahresergebnisse bei 42 Patienten.

BACKGROUND: Initial results after autologous fat transfer for treatment of thumb carpometacarpal joint osteoarthritis have been promising. But long-term results have not yet been available. METHODS: In a prospective study, 42 patients with thumb carpometacarpal joint osteoarthritis were observed for a mean time of 5 years after autologous fat transfer. Manual liposuction and centrifugation were performed. Pain rating according to numerous analogue pain scale; objective force of pinch grip and fist closure; and Disabilities of the Arm, Shoulder, and Hand questionnaire score (DASH score) before and after treatment were analysed. RESULTS: The average pain preoperatively was 8.0 ± 1.6 and 4.0 ± 3.0 after 5 years overall. Force and pinch force of the treated hand improved from 71% and 60% preoperative in comparison to the non-treated hand to 100% and 96%, respectively, 5 years after fat transplantation. There were similar improvements for the parameters strength and DASH score. All improvements were statistically significant. No serious adverse events were observed. CONCLUSIONS: Autologous fat transplantation is a real alternative to trapeziectomy even in the long term in basal joint osteoarthritis of the thumb. The low invasiveness of the procedure and early recovery of patients compared with classical procedures such as trapeziectomy, and the superior long-term results compared with classical injection therapy, make this approach feasible as a first-line therapy in basal joint osteoarthritis of the thumb as it offers stable results and warrants a high patient satisfaction rate.

Preparation of human amniotic membrane for transplantation in different application areas.

The human amniotic membrane (hAM) is the inner layer of the placenta and plays protective and nutritional roles for the fetus during pregnancy. It contains multiple growth factors and proteins that mediate unique regenerative properties and enhance wound healing in tissue regeneration. Due to these characteristics hAM has been successfully utilized in ophthalmology for many decades. This material has also found application in a variety of additional therapeutic areas. Particularly noteworthy are the extraordinary effects in the healing of chronic wounds and in the treatment of burns. But hAM has also been used successfully in gynecology, oral medicine, and plastic surgery and as a scaffold for in vitro cell culture approaches. This review aims to summarize the different graft preparation, preservation and storage techniques that are used and to present advantages and disadvantages of these methods. It shows the characteristics of the hAM according to the processing and storage methods used. The paper provides an overview of the currently mainly used application areas and raises new application possibilities. In addition, further preparation types like extracts, homogenates, and the resulting treatment alternatives are described.

Infections in Burn Patients: A Retrospective View over Seven Years.

Backgroundand objectives: Burn patients represent a challenging cohort because the injuries entail a vulnerability to colonisation by microorganisms. The ensuing infections can lead to serious complications and, in many cases, to the death of the burn patient. Surgical intervention and wound dressings, as well as antibiotic treatment, are crucial for optimising the treatment of the patient. Materialand Methods: In this retrospective analysis, we analysed the treatment course, antibiotic therapy, and general complications of 252 burn patients with second- or third-degree burns over a time span of 7 years. Results: Patients who developed infections tended to have, on average, a higher total body surface area (TBSA), higher abbreviated burn severity index (ABSI) scores, and longer hospital stays. Patients who were admitted to the burn unit after 2006 had significantly shorter stays in the burn unit. TBSA and ABSI scores were lower in the patient cohort admitted after 2006. Patients exhibiting a TBSA greater than 30% had significantly longer hospital stays and antibiotic treatment periods. TBSA and ABSI scores were significantly higher in patients who died. The results of binary logistic regression indicate that a higher ABSI score increases the odds ratio of developing an infection. Bacteria number had no significant effect on the odds of patient death but positively influenced the odds ratio of developing an infection. TBSA was negatively associated with the risk of developing an infection and was an insignificant predictor of mortality. Conclusions: To gauge the optimal treatment for a burn patient, it is crucial for practitioners to correctly select, dose, and time antibiotics for the patient. Monitoring bacterial colonisation is vital to nip rising infection in the bud and ensure the correct antibiotic selection. This will help prevent the development of multi-resistant bacteria.

Burn Injury: Mechanisms of Keratinocyte Cell Death.

Cutaneous burn injury is associated with epidermal loss in the zone of coagulation zone and delayed tissue loss in the zone of stasis. Thus, thermal stress can trigger both necrosis and regulated cell death (RCD) or apoptosis. Experimental in vitro and in vivo work has clearly demonstrated apoptotic events of thermally injured keratinocytes that are accompanied by morphological and biochemical markers of regulated cell death. However, in vivo data for the different pathways of regulated cell death are sparse. In vitro experiments with heat-stressed human keratinocytes have demonstrated death receptor involvement (extrinsic apoptosis), calcium influx, and disruption of mitochondrial membrane potential (intrinsic apoptosis) in regulated cell death. In addition, caspase-independent pathways have been suggested in regulated cell death. Keratinocyte heat stress leads to reduced proliferation, possibly as a result of reduced keratinocyte adhesion (anoikis) or oncogene involvement. Understanding the underlying mechanisms of RCD and the skin's responses to thermal stress may lead to improved strategies for treating cutaneous burn trauma.

[Improvement in burn wound care: summary of the AWMF guideline for the treatment of thermal injuries in adults]. / Optimierung der chirurgischen Behandlung Brandverletzter: Auszüge aus der fachübergreifenden S2k-Leitlinie "Behandlung thermischer Verletzungen des Erwachsenen".

INTRODUCTION: More than half a million patients suffer from minor burns in Germany per year. In 2018, almost 2000 patients needed intensive care for their burn injuries. Despite high standards of burn care, mortality remains high. Burn injuries may lead to long-term sequelae. In order to provide up-to-date burn care, guidelines are available online with public access. METHODS AND RESULTS: This overview presents a summary of the German AWMF guideline for the treatment of thermal injuries in adults (https://www.awmf.org/leitlinien/detail/ll/044-001.html). Experts of eleven different medical organisations and specialties have contributed to this S2k guideline with their expertise. The focus of the article is on acute burn wound assessment, the indication for specialised care in burn centres, the management of the burn wound at the trauma scene and in hospitals as well as scar management and rehabilitation. CONCLUSION: This overview reports on the consensus-based treatment of acute burn wounds in adults in Germany. The article is intended to guide doctors and professional caretakers to perform state-of-the-art burn care. The current guideline aims to improve burn outcome.

Does Increased Patient Load Improve Mortality in Burns?: Identifying Benchmark Parameters Defining Quality of Burn Care.

INTRODUCTION: In burn care, as in other medical fields, there is a tendency to increase the required number of patients for center certifications. Does the increase in patient load automatically improve the quality of burn care? What are the benchmark parameters that have been shown to improve burn care? METHODS: To answer these questions, Medline, Cochrane Library, and Livivo were searched from inception through January 2018 for all studies evaluating the influence of treatment parameters on outcomes in different burn care settings. RESULTS: Fifteen studies were included in this systematic review. In adults, not a single study showed a decreased mortality due to a higher patient load. However, in children, 2 studies demonstrated a further decrease of the already low mortality due to an increase in patient load. In contrast to patient load, benchmark parameters that had a significant influence on the outcome of burn care for adults and children were: single bed isolation, residency programs, American Burn Association certifications of burn centers, speed of wound closure, and standard operating procedures for burn care. CONCLUSIONS: This systematic review demonstrates that a clear correlation between patient load and mortality reduction in adult burn treatment is not supported by the existing literature, requiring future studies. In contrast, all efforts aiming to improve the quality of burn care, such as isolation of burn patients, speed of wound closure, American Burn Association verification and especially standard operating procedures for burn care improve survival and quality of burn care.

Porcine-derived biomaterials in tissue engineering and reconstructive surgery: Considerations and alternatives in Muslim patients.

During the last three decades, tissue engineering and reconstructive surgery have become standard therapeutic options in the world of medicine. Several biomaterials, either alone or in combination with cultured cellular products, have been introduced to compensate for the scarcity of autologous donor tissue or to improve healing in a variety of surgical specialties, for example, abdominal/visceral surgery, plastic surgery, and cardiovascular surgery. Many of these biomaterials are of porcine origin. It is well known that Islam has prohibited the consumption of porcine or any of its products. With Muslims accounting for 23% (1.6 billion) of the global population, a thorough review of the implications of porcine-derived tissue-engineered products in surgery seems necessary. In life-threatening conditions as well as severe diseases, the use of porcine-derived products is permissible if similar non-porcine-derived materials are not available. In this case, the use of porcine-derived products represents a necessity and is allowed. Therefore, this distinction between sole need and necessity has great importance not only for the medical community but also for researchers in biotechnology and industry who may consider alternatives to porcine-derived materials.

Betulin wound gel accelerated healing of superficial partial thickness burns: Results of a randomized, intra-individually controlled, phase III trial with 12-months follow-up.

OBJECTIVE: Acceleration of wound healing promises advantages for patients and caregivers in reducing the burden of disease, avoiding complications such as wound infections, and improving the long-term outcome. However, medicines that can accelerate wound healing are lacking. The objective of this open, blindly evaluated, randomized, multicenter phase III study was to compare intra-individually the efficacy and tolerability of Oleogel-S10 with fatty gauze dressing versus Octenilin® wound gel with fatty gauze dressing in accelerating the healing of superficial partial thickness burn wounds. METHODS: Acute superficial partial thickness burn wounds in adults caused by fire, heat burn or scalding were divided into 2 halves and randomly assigned to treatment with Oleogel-S10 or Octenilin® wound gel. Photos for observer-blinded analysis of wound healing were taken at each wound dressing change. Percentages of reepithelialization were assessed at defined intervals. Efficacy and tolerability were evaluated based on a 5-point Likert scale. RESULTS: Of 61 patients that were enrolled, 57 received the allocated intervention and 48 completed treatment. The percentage of patients with earlier wound healing was significantly higher for Oleogel-S10 (85.7%, n=30) compared to Octenilin® wound gel (14.3%, n=5, p<0.0001). The mean intra-individual difference in time to wound closure was -1.0 day in favour of Oleogel-S10 (-1.4, -0.6; 95% CI, p<0.0001). Most investigators (87.0%) and patients (84.8%) evaluated the efficacy of Oleogel-S10 to be 'better' or 'much better' than that of Octenilin® wound gel. Long-term outcome 3 months and 12 months post injury was improved in some patients. CONCLUSIONS: Oleogel-S10 (Episalvan) significantly accelerated the healing of superficial partial thickness burn wounds. It was safe and well tolerated.

Burn Scar Evaluation Using the Cutometer® MPA 580 in Comparison to "Patient and Observer Scar Assessment Scale" and "Vancouver Scar Scale".

The effect of the "Patient and Observer Scar Assessment Scale" (POSAS) and "Vancouver Scar Scale" (VSS) on patients' quality of life and their correlation with objective scar assessment tools, such as the Cutometer®, is not fully elucidated. In addition, long-term results of the dermal substitute Matriderm® used in combination with split-thickness skin grafting (STSG) remain unclear. We evaluated burn scars of 45 patients at least 2 years postburn injury using the Cutometer® MPA 580, the VSS, and the POSAS with three additional questions regarding quality of life and correlated the results. Study groups were: 1) scars following conservative treatment, 2) scars following STSG, and 3) scars following STSG in combination with Matriderm®. Cutometer® measurements demonstrated better elastic qualities in the Matriderm® group compared with the STSG group. VSS and extended POSAS were rated best for the conservative group, followed by the STSG group and the Matriderm® group. There was a significant correlation between POSAS and VSS, quality of life and the objective Cutometer® measurements. Conservatively treated superficial dermal burns do not reach the elastic qualities of healthy skin, and the use of Matriderm® significantly improves the long-term elastic qualities of STSG in deep dermal and full-thickness burns 2 years post injury. Results from the VSS and the POSAS correlate with restrictions in the quality of life of patients and also with objective Cutometer® measurements and are therefore useful tools in scar evaluation following burn injury.