Radana Königova

A recombined skin composed of human keratinocytes cultured on cell-free pig dermis

Treatment of full skin thickness burns requires replacement of both the dermal and the epidermal components of the skin. We describe a method of preparing recombined human/pig skin (RHPS) by cultivating human keratinocytes on dried cell-free pig dermis (CFPD). CFPD dried on a tissue culture dish forms a thin collagen film which behaves like a firm substrate for cell cultures. HK were grown on the epidermal side of the CFPD using lethally irradiated 3T3 cells as feeders. After reaching confluency of human keratinocytes, human fibroblasts can be cultured on the dermal side of the RHPS. It was possible to obtain approximately 500 cm2 of the RHPS from 1 cm2 human split-skin graft in 3 weeks. RHPS is easy to handle, is similar in structural, mechanical and adhesive properties to the normal skin, and can be meshed. This RHPS might be advantageous for permanent covering of wounds in major burns.

Toxic epidermal necrolysis and Stevens‐Johnson syndrome at the Prague Burn Centre 1998–2008

Background  Toxic epidermal necrolysis (TEN) and Stevens‐Johnson syndrome (SJS) are skin disorders characterized by extensive necrosis of the mucous membranes and the epidermis caused by an autoimmune response.

Human Keratinocyte Growth and Differentiation on Acellular Porcine Dermal Matrix in relation to Wound Healing Potential

A number of implantable biomaterials derived from animal tissues are now used in modern surgery. Xe-Derma is a dry, sterile, acellular porcine dermis. It has a remarkable healing effect on burns and other wounds. Our hypothesis was that the natural biological structure of Xe-Derma plays an important role in keratinocyte proliferation and formation of epidermal architecture in vitro as well as in vivo. The bioactivity of Xe-Derma was studied by a cell culture assay. We analyzed growth and differentiation of human keratinocytes cultured in vitro on Xe-Derma, and we compared the results with formation of neoepidermis in the deep dermal wounds treated with Xe-Derma. Keratinocytes cultured on Xe-Derma submerged in the culture medium achieved confluence in 7–10 days. After lifting the cultures to the air-liquid interface, the keratinocytes were stratified and differentiated within one week, forming an epidermis with basal, spinous, granular, and stratum corneum layers. Immunohistochemical detection of high-molecular weight cytokeratins (HMW CKs), CD29, p63, and involucrin confirmed the similarity of organization and differentiation of the cultured epidermal cells to the normal epidermis. The results suggest that the firm natural structure of Xe-Derma stimulates proliferation and differentiation of human primary keratinocytes and by this way improves wound healing.

New biological temporary skin cover Xe-Derma® in the treatment of superficial scald burns in children

BACKGROUND Xe-Derma® is a new dry sterile biological cover derived from acellular pig dermis. Hydrated Xe-Derma® displays bio-mechanical features similar to the normal skin. The aim of the present study was to compare the efficacy of Xe-Derma® with hydrocolloid dressing Askina THINSite® for treatment of superficial burns in children in a prospective study. MATERIALS AND METHODS In a prospective study, 86 patients (5 months to 7 years of age) with superficial scald burns on a surface area of 1-35% BSA were enrolled. In the course of the study, 43 patients were treated with Xe-Derma® and 43 patients with Askina THINSite®. We collected data including the percentage of BSA covered with biological or synthetic material, epithelization time, the number of complete conversions (deepening of 100% of covered area into deep dermal wound) under each cover, the number and extent of partial conversions (deepening of less then 100% of covered area into deep dermal wound), infectious complications, the number of reapplications of the temporary cover and the extent in square centimetres of dressing material needed for successful healing of 1% BSA. RESULTS No significant difference in the epithelization time, percentage of conversion from superficial to deep dermal burns and percentage of infectious complication was detected between the two groups. However, patients in the Xe-Derma® group were burned on a more extensive burn surface area (p ≤ 0.028). Xe-Derma® showed adherence to the wound and therefore there has been no need to be changed The number of reapplications and therefore also the number of square centimetres needed for successful healing of 1% BSA were statistically higher in the Askina THINSite® group (p < 0.01) due to increased secretion and accumulation of fluid underneath this hydrocoloid cover. The minimal frequency of changes of this biological cover material brings a significant benefit to pediatric patients. CONCLUSION Acellular pig dermis Xe-Derma® represents a reliable biological cover material. It is an advantageous alternative to synthetic temporary skin covers in the treatment of superficial scald burns in children.

Immunoglobulin E (IgE) in patients with severe burns

The concentrations of immunoglobulin E (IgE) were measured serially in 30 patients with severe burn injury. A characteristic finding was a rapid and dramatic increase of IgE in the serum of all patients, some of whom showed up to 20-fold increases. IgE was also found in considerable amounts in blister fluid and pleural effusions. In some patients raised IgE values were the only indicator of an anamnestic immediate allergic state. No correlation was found between the IgE levels and clinical characteristics of individual patients but significant changes seemed to be present only in patients with a burn covering more than 20 per cent of the body surface area.

Prevention of burn wound conversion by allogeneic keratinocytes cultured on acellular xenodermis.

Deep dermal burns frequently tend to convert into full-thickness skin loss. We found that this wound deepening may be prevented by recombined human/pig skin (RHPS), consisting of human allogeneic keratinocytes cultured on acellular pig dermis. RHPS has skin-like consistency and therefore optimal adhesiveness to the wound. It can be easily removed from the dish and transferred to the recipient. The wound bed has to be prepared by tangential excision or deep dermabrasion to the level of capillary bleeding. RHPS has to be applied ‘upside-down’, with the epidermal layer facing the wound, to avoid the dermal matrix forming a barrier to the nutrients for the keratinocytes. In our practice, more than 70% of early excised or deeply dermabraded wounds grafted with RHPS healed in the course of one week after keratinocyte transplantation.

Natural Killer Cell Activity Following Thermal Injury

The role of natural killer cell activity in immunosurveillance following thermal injury remains unknown. We utilize a chromium-51-release assay of K562 targets to monitor NK activity. NK activity of peripheral blood mononuclear cells of severely burned patients (BSA greater than 20%) was determined once a week until the convalescence period was completed. From the second week after thermal injury, impairment of NK activity was demonstrated, but the differences did not reach statistical significance. However, a correlation was found between decline of NK activity and incidences of septic complications. Surprisingly, no decline in NK activity was observed in the first week after thermal injury.

Psychology associated with mass burn disasters

Abstract Mental breakdowns occur in war as well as in mass disasters. Not only are men exposed to far more stress, but they are expected to stand up to it and are not permitted to escape. The question why these mental breakdowns occur can be asked and could be explained by the following: 1. 1. Mass disasters initiate much impulsive to irrational behaviour of the victims as well as of their relatives. 2. 2. The severely burned are not aware of the seriousness of their injury, as they are influenced by biopsychic impulses and by emotional factors. 3. 3. A great number of burned patients die not only because of their physical injury, but also because they often have little chance of surviving in the general panic. 4. 4. Developing burn injury is concomitantly associated with psychologic and psychiatric symptoms. 5. 5. Psychological aspects and measures help the doctor to differentiate the cases and consider the risks to the lives of the individual victims. On the basis of the above considerations the authors worked out a model of psychological management and treatment during disasters: personnel and technical equipment of the so called centre for information and psychological support, and of the so called psycho-accommodation stations. The cooperation of these improvised facilities with the other strategic points of the emergency is discussed.

A histological analysis of artificial skin in an extensively burned child, 14 years after application: a case report

INTRODUCTION Artificial skin has become the treatment of choice in extensive, full-thickness thermal injuries. The longest follow-up of the healing process in burn sites covered with the Integra Bilayer Matrix Wound Dressing onto the wound published to date was at around five years after application. In our case report, we describe the clinical and histological analysis of an extensive, full-thickness thermal injury 14 years on from treatment with the bilayer matrix wound dressing. CASE STUDY A nine-year-old boy suffered a full-thickness skin loss over 85% of his body surface area following a fire accident. The bilayer matrix wound dressing was used on both legs and covered almost 30% of his body surface area. Cosmetic and functional results were satisfactory. Histological analysis performed nine years after the application of the bilayer matrix wound dressing onto the wound showed a double-layered skin composition with changes in the fibrous component of the dermis. CONCLUSION Despite satisfactory short- and long-term clinical results from applications of the bilayer matrix wound dressing, we found important differences in microstructure when compared with the physiological condition.

System of postgraduate training in burn emergencies in Prague

The science of disaster planning has shown that the severity of a burn disaster is magnified by the total number of burn injuries. In 1982 Sorensen pointed out that the overall sum is in any case large, whether it is a question of few severe injuries or many smaller ones, and specified that they require a large burns centre or unit.