A new approach to the production of a biovital skin graft based on human acellular dermal matrix produced in-house, in vitro revitalized internally by human fibroblasts and keratinocytes on the surface.

Patients with extensive and deep burns who do not have enough donor sites for autologous skin grafts require alternative treatment methods. Tissue engineering is a useful tool to solve this problem. The aim of this study was to find the optimal method for the production of a biovital skin substitute based on acellular dermal matrix (ADM) and in vitro cultured fibroblasts and keratinocytes. In this work, nine methods of ADM production were assessed. The proposed methods are based on the use of the following enzymes: Dispase II, collagenase I/ethylenediaminetetraacetic acid (EDTA), collagenase II/EDTA, and mechanical perforation using DermaRoller and mesh dermatome. The obtained ADMs were examined (both on the side of the basement membrane and on the "cut-off" side) by means of scanning electron microscopy, immunohistochemistry tests and strength tests. ADM was revitalized with human fibroblasts and keratinocytes. The ability of in-depth revitalization of cultured fibroblasts and their ability to secrete collagen IV was examined. The obtained results indicate that the optimal method of production of live skin substitutes is the colonization of autologous fibroblasts and keratinocytes on the scaffold obtained using two-step incubation method: Trypsin/EDTA and dispase II.

Surface structure changes of pathological placenta tissue observed using scanning electron microscopy - a pilot study.

Structural changes within the placenta are observed in the course of pathological pregnancy. The aim of the study was to perform initial assessment of morphological features of placenta. The analysis was conducted by Scanning Electron Microscopy. Samples of placenta of women who delivered neonates appropriate for gestational age were characterized by a homogenous surface texture with natural corrugation. The surface of IUGR placenta from the group of mothers with pregnancy induced hypertension was definitely heterogeneous - noticeable swelling of tissue surface was observed. Samples from LGA group also demonstrated a number of surface bulges and heterogeneities which were, nonetheless, characterized by a certain repeatability.

The role of topically applied l-ascorbic acid in ex-vivo examination of burn-injured human skin.

Wound treatment and healing is complex and is comprised of an elaborate set of processes including cellular, spectroscopic and biochemical ones as well as the "reaction" of local tissue to thermal injury. Vitamin C as l-ascorbic acid (LA) prevents injurious effects of oxidants because it reduces reactive oxygen species to stable molecules, it becomes oxidized to the short-lived ascorbyl radical. As a result, antioxidant treatment may contribute to minimizing injury in burn patients. The aim of this study is to assess changes in molecular structure of collagen extracted from human epidermis burn wound scab during incubation of the epidermis in l-ascorbic acid solution. The study will be performed using FTIR and FT Raman spectroscopies. During this research it was observed that the intensity of Raman peaks increased where healing was being modified by LA. The intensity of the amide III band at 1247cm-1 relative to the intensity at 1326cm-1 was used to test tissue repair degree at the incision site. FTIR spectra were recorded from frozen specimens of serum modified by LA; an analysis of shifts in the amide I band position was conducted. The appearance of a new band for frozen samples modified by LA was observed around 1149-1220cm-1. The above conclusions confirmed the creation of hydrogen bonds between NH stretch and CO. Samples being incubated in solutions of l-ascorbic acid demonstrated the absence of electrophoretic bands of albumin. Alterations in the surface of the skin incubated in l-ascorbic acid were investigated with the use of Scanning Electron Microscopy (SEM). A decrease in external symptoms of burn injury was noted in the damaged epidermis incubated in l-ascorbic acid.

Active antioxidants in ex-vivo examination of burn wound healing by means of IR and Raman spectroscopies-Preliminary comparative research.

Being a complex traumatic event, burn injury also affects other organ systems apart from the skin. Wounds undergo various pathological changes which are accompanied by alterations in the molecular environment. Information about molecules may be obtained with the use of Raman spectroscopy and Fourier-transform infrared spectroscopy, and when combined, both methods are a powerful tool for providing material characterization. Alterations in the molecular environment may lead to identifying objective markers of acute wound healing. In general, incubation of samples in solutions of l-ascorbic acid and 5% and 7% orthosilicic acid organizes the collagen structure, whereas the increased intensity of the Raman bands in the region of 1500-800cm-1 reveals regeneration of the burn tissue. Since oxidative damage is one of the mechanisms responsible for local and distant pathophysiological events after burn, antioxidant therapy can prove to be beneficial in minimizing burn wounds, which was examined on the basis of human skin samples and chicken skin samples, the latter being subject to modification when heated to a temperature sufficient for the simulation of a burn incident.

Inhibitors of thermally induced burn incidents ­ characterization by microbiological procedure, electrophoresis, SEM, DSC and IR spectroscopy.

Differential scanning calorimetry (DSC) and thermogravimetric (TGA) investigations, acetate electrophoresis (CAE), Fourier-transform infrared spectrometry (FTIR), scanning electron microscopy (SEM) analysis and microbiological procedures were all carried out after heating the samples to a temperature sufficient for simulating a burn incident. In particular, the purpose of the present study was to analyze the effect of antioxidants, such as fucoidan from brown seaweed and flame-retardant cyclic organophosphates and phosphonates, on an organic chicken skin that gets changed by a burn incident. DSC was considered to be a useful tool in assessing in vitro temperature-mediated cross-linking; an innovative analytical conclusion was obtained from the experimentation described in the paper. FTIR tests revealed that heating a dry organic chicken skin to the boiling point leads to the disappearance of a wide band in the 1650-1550 cm(-1) area or the conversion of a band, which may be attributed to the intermolecular ß-sheet aggregates. Fucoidan from brown seaweed and flame-retardant cyclic organophosphates and phosphonates probably bind with the collagen that is changed by the burn (in addition to the influence of antioxidant solutions on samples of a blank or not boiled organic chicken skin) incident forming a polymer film with the collagen of the chicken skin surface (SEM analysis), decreasing the aggregation process and native collagen recovery. Good bacteriostatic properties were determined for fucoidan samples from brown seaweed and flame-retardant cyclic organophosphates and phosphonates against the pathogenic bacteria Escherichia coli and Staphylococcus aureus. Thus, it was observed that the fucoidan incorporated into collagen films can be used as a therapeutically active biomaterial that speeds up the wound-healing process.