Development of an in vitro burn wound model

Healing of a deeper burn wound is a complex process that often leads to scar formation. Skin wound model systems are important for the development of treatments preventing scarring. The aim of this study is to develop a standardized in vitro burn wound model that resembles the in vivo situation. A burn wound (10 × 2 mm) was made in ex vivo skin and the skin samples were cultured at the air–liquid interface for 7, 14, and 21 days. Cells in the skin biopsies maintained their viability during the 21-day culture period. During culture, reepithelialization of the wound took place from the surrounding tissue and fibroblasts migrated into the wound area. Cells of the epithelial tongue and fibroblasts near the wound margin were proliferating. During culture, skin-derived antileukoproteinase and keratin 17 were expressed only in the epithelial tongue. Both collagen type IV and laminin were present underneath the newly formed epidermis, indicating that the basement membrane was restored. These results show that the burn wound model has many similarities to in vivo wound healing. This burn wound model may be useful to study different aspects of wound healing and testing pharmaceuticals and cosmetics on, e.g., migration and reepithelialization.     

A case of congenital supratentorial tumor: Atypical teratoid/rhabdoid tumor or primitive neuroectodermal tumor?

Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT.     

ENDOSCOPIC MUCOSAL RESECTION AND SUBMUCOSAL DISSECTION METHOD FOR LARGE COLORECTAL TUMORS

The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms.     

Post‐traumatic reactions among rescue personnel 96 hours after the Hilton Hotel bombing in Sinai: The effect of previous exposure

This paper considers the immediate post‐traumatic reactions of rescue personnel who were exposed to the Hilton Hotel bombing in Sinai. The entire rescue personnel (n = 26) were assessed and separated into two groups on the basis of previous exposure to the same type of trauma. The results suggest that among rescue personnel, those with previous exposure had a lower level of post‐traumatic symptoms than those who were being exposed for the first time. This supports the hypothesis that previous exposure to the same type of trauma has an immunizing effect for subsequent same type of traumatic event among rescue personnel. Copyright © 2005 John Wiley & Sons, Ltd.