Improvement in Biocompatibility and Biointegration of Human Acellular Dermal Matrix through Vacuum Plasma Surface Treatment.

Efforts are ongoing to enhance the functionality of human acellular dermal matrices (hADMs), which are extensively utilized in reconstructive surgeries. Among these efforts, plasma treatments, particularly vacuum plasma treatments, have recently emerged in the medical field. This study aims to investigate the efficacy of a vacuum plasma treatment in enhancing the biocompatibility and biointegration of hADMs. Utilizing a plasma activator (ACTILINK reborn, Plasmapp Co., Ltd., Daejeon, Republic of Korea), hADMs were treated and evaluated through in vitro and in vivo analyses. Hydrophilicity changes were gauged by the blood absorption times, while SEM imaging was used to analyze physical surface deformation. Protein adsorption was measured with fluorescently labeled bovine serum albumin and fibronectin. For the in vivo study, mice were implanted with plasma-treated and untreated hADMs, and the post-implantation effects were analyzed through histological and immunofluorescence microscopy. The plasma-treated hADMs demonstrated a significantly enhanced hydrophilicity compared to the untreated samples. SEM imaging confirmed the maintenance of the microroughness after the treatment. The treated hADMs showed a significant reduction in fibronectin adsorption, a critical factor for cellular adhesion. In vivo, the plasma-treated hADMs exhibited reduced capsule formation and enhanced fibroblast infiltration, indicating improved biocompatibility and integration. These findings highlight the potential of a plasma treatment to enhance the performance of hADMs in clinical settings, offering a promising avenue for improving reconstructive surgery outcomes.

In Vivo Efficacy of an Injectable Human Acellular Dermal Matrix.

BACKGROUND: Human acellular dermal matrix (hADM) has found applications in a variety of settings, particularly in breast surgery. The most common hADM is a sheet. Recently, an injectable hADM has been introduced; we compared the biocompatibility and long-term structural integrity of, an injectable hADM and a sheet-type hADM in mice. METHODS: An injectable hADM (experimental group) and a sheet-type hADM (control group) were implanted into sub-panniculus pockets on the backs of 50 mice. The animals were sacrificed 2, 4, 8, 12, or 24 weeks later and the hADMs and surrounding tissues were recovered and stained for histopathological analyses. The microscopic endpoints included the thickness of the hADM and capsule around the hADM, and the extents of fibroblast proliferation and neovascularization. RESULTS: No animal developed a complication or infection. The capsule was significantly thinner in the experimental than the control group. There were no significant differences between groups in the hADM thickness. Microscopically, the fibroblast density inside the hADM was significantly higher in the experimental group. The fibroblasts inside of the hADM lay significantly deeper in the experimental group. Similarly, the experimental group exhibited significantly deeper microvessels inside the hADM. CONCLUSIONS: The injectable hADM had a thinner capsule thickness (more biocompatible), than the sheet-type hADM. It maintained its thickness as well as the sheet-type hADM and had a more fibroblast proliferation and neovascularization. This means the tissue incorporation and long-term structural integrity of the injectable hADM may be as good as or better than that of the sheet-type hADM. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Tauroursodeoxycholic Acid Decreases Keloid Formation by Reducing Endoplasmic Reticulum Stress as Implicated in the Pathogenesis of Keloid.

Keloids are a common form of pathologic wound healing and are characterized by an excessive production of extracellular matrix. This study examined the major contributing mechanism of human keloid pathogenesis using transcriptomic analysis. We identified the upregulation of mitochondrial oxidative stress response, protein processing in the endoplasmic reticulum, and TGF-ß signaling in human keloid tissue samples compared to controls, based on ingenuity pathway and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Electron microscopic examinations revealed an increased number of dysmorphic mitochondria and expanded endoplasmic reticulum (ER) in human keloid tissue samples than that in controls. Western blot analysis performed using human tissues suggested noticeably higher ER stress signaling in keloids than in normal tissues. Treatment with tauroursodeoxycholic acid (TUDCA), an ER stress inhibitor, significantly decreased scar formation in rabbit models, compared to normal saline and steroid injections. In summary, our findings demonstrate the contributions of mitochondrial dysfunction and dysregulated ER stress signaling in human keloid formation and the potential of TUDCA in the treatment of keloids.

Qualitative and Quantitative Analyses of Donor Site Morbidity Following a Graft of the Acellular Dermal Matrix Versus Primary Fascial Repair After ALT Flap Harvesting.

BACKGROUND: The anterolateral thigh (ALT) flap is one of the most useful flaps in reconstruction because of its reliability, large skin flap territory, and versatility. The relatively small number of side effects is a common reason for preferring this flap. Primary repair is usually performed at the donor site closure; however, this requires substantial tension and causes many donor site morbidities, including pain. We attempted to use acellular dermal matrix graft to overcome these problems. METHODS: We analyzed a total of 41 cases (41 flaps) in this study. Among these flaps, we conducted donor fascia suture with artificial dermis in 20 cases (study group) and primary fascial suture in 21cases (control group). Post-operative ambulation recovery times, pain scores, drainage removals, and wound problems of the donor site were recorded. RESULTS: There were no serious complications, including infection, at the donor sites of all 41 cases. Of 20 cases using the acellular dermal matrix, seroma occurred in 2 cases and partial skin necrosis occurred in 2 cases. In 1 case of skin necrosis, the acellular dermal matrix was removed. However, in comparison to the control group, the group using the artificial dermis recovered ambulatory ability 3.9 days earlier and had a 1.8-point lower visual analogue scale score 5 days post-operatively. CONCLUSIONS: Our study suggested that, if used selectively, the acellular dermal matrix may play an effective role in donor site closure in cases with procedures involving the ALT flap.

HISTORIQUE: Le lambeau antérolatéral de la cuisse est l'un des plus utiles pour la reconstruction à cause de sa fiabilité, de son grand territoire et de sa polyvalence. Le relativement petit nombre d'effets secondaires est une raison courante pour le préférer. La réparation primaire est généralement effectuée à la fermeture du site du donneur, mais il faut une tension importante, ce qui entraîne de nombreuses morbidités au site du donneur, y compris la douleur. Les chercheurs ont tenté d'utiliser une greffe de la matrice dermique acellulaire pour vaincre ces problèmes. MÉTHODOLOGIE: Les chercheurs ont analysé un total de 41 cas (41 lambeaux) dans cette étude. De ce nombre, ils ont effectué une suture du fascia du donneur à l'aide de derme artificiel dans 20 cas (groupe d'étude) et une suture fasciale primaire dans 21 cas (groupe témoin). Ils ont également pris note de la durée de convalescence ambulatoire postopératoire, des scores de douleur, de la désinstallation du drainage, et des problèmes de plaie au site du donneur. RÉSULTATS: Il n'y a pas eu de complications graves, y compris l'infection, aux sites des donneurs des 41 cas. On a observé un sérome dans deux des 20 cas faisant appel à la matrice dermique acellulaire, et une nécrose cutanée partielle dans également deux cas. Dans l'un des cas de nécrose cutanée, la matrice dermique acellulaire a dû être retirée. Cependant, comparativement au groupe témoin, le groupe qui a utilisé le derme artificiel a récupéré sa capacité ambulatoire 3,9 jours plus rapidement et présentait un score de 1,8 point de moins à l'échelle analogique visuelle cinq jours après l'opération. CONCLUSIONS: Selon la présente étude, la matrice dermique acellulaire utilisée sélectivement peut jouer un rôle efficace à la fermeture du site du donneur dans les cas d'intervention faisant appel au lambeau antérolatéral de la cuisse.

Cadaveric study of deep temporal fascia for autologous rhinoplasty grafts: Dimensions of the temporal compartment in Asians.

BACKGROUND: Due to the anatomical complexity of the deep temporal fascia (DTF), practical guidelines for its safe harvest are lacking. However, since the upper temporal compartment (UTC) contains no vital structures, it may provide safe access for DTF harvest. This study aimed to identify the anatomical structures of the temporal compartment in Asian cadavers and to measure their dimensions to enable safe DTF harvest. METHODS: The anatomical structures surrounding the temporal compartment were identified in 27 hemifaces from 15 Korean cadavers. After dissection, digital images were acquired and craniometric landmarks were placed upon them to identify the boundaries of the temporal compartment. The horizontal and vertical lengths of the temporal compartment were measured and their surface areas were computationally assessed. Subsequently, differences in the results by sex were evaluated. RESULTS: The five-layer anatomical structure of the UTC was clearly visualized. The UTC was bounded by the temporal septa superiorly and inferiorly, the innominate fascia laterally, and the DTF medially. No vital structures were present within the UTC. The vertical and horizontal lengths of the UTC were 6.41±0.67 cm and 10.44±0.83 cm, respectively, and the surface area of the UTC was 48.52±5.65 cm2. No statistically significant differences were observed in any dimensions between male and female patients. CONCLUSIONS: During rhinoplasty, DTF can be harvested as an autologous graft material from the UTC. An anatomical understanding of the UTC will aid in the safe and simple harvest of a sufficient amount of DTF.

In Vitro and in Vivo Biocompatibility and Degradability Evaluation of Modified Polydioxanone Plate.

BACKGROUND: Polydioxanone (PDS) has been widely used in the medical field over the past 30 years. In the 2000s, PDS plate began to be used for rhinoplasty and septoplasty. However, in Asia PDS plates are not widely used due to lack of awareness and high prices. The authors devised a method of producing a modified PDS (m-PDS; Rhinoblock Material & Design Co., Gyeonggi-do, Sothh Korea) at low cost, and compared the biocompatibilities and degradabilities of plates produced with m-PDS and commercial PDS plates (Ethicon, Somerville, NJ) in vivo and in vitro. METHODS: The melting point and decomposition rate of m-PDS were determined by differential scanning calorimetry and thermogravimetric analysis and its tensile strength was also measured. Implants (1 cm × 1 cm × 0.15 mm sized) were inserted subcutaneously into mice and harvested en bloc 2, 5, 10, 15, or 25 weeks later. Tissues were stained with hematoxylin and eosin or Masson's trichrome to evaluate inflammation, extracellular matrix deposition, and vascularization, and plate degradability was also assessed. RESULTS: No significant difference was observed between the thermal analysis and tensile test results of m-PDS and PDS plates. m-PDS started to degrade in vivo from around 10 weeks, and commercial PDS plates from around 15 weeks. After 25 weeks in vivo, both products were completely degraded and not observed in tissue slides. Histologic analysis of excised specimens showed m-PDS and PDS were similar in terms of inflammation, extracellular matrix deposition, and vascularization. CONCLUSION: In vivo and in vitro experiments detected no significant difference between the biocompatibilities and degradabilities of modified and commercial PDS plates. The results of this study suggest that the modified PDS can be used to produce versatile, low cost, absorbable graft materials for rhinoplasty and septoplasty.