Human de-epidermized dermis as a stem cell carrier.

Recently several types of skin equivalents have been developed, consisting of differentiated keratinocytes cultured on various dermal substitutes. Different models of reconstructed human skin have been proposed, such as human and animal de-epidermized dermis, inert filters, collagen matrices, lyophilized collagen membranes populated with fibroblasts, and other models populated with melanocytes and/or Langerhans cells. These skin equivalents mimic native skin in vivo. They have provided information about dermal-epidermal interactions, cell-cell, and cell-matrix interactions; responses of dermal and epithelial cells to biological signals and pharmacological agents; as well as effects of drugs and growth factors on wound healing. Human allodermis from tissue banks has been used for clinical purposes, namely, as support for autologous keratinocyte cultures and as a potentially ideal scaffold for dermal replacement. This bioproduct is considered to be the most suitable clinical carrier for autologous fibroblasts and keratinocytes, as well as an useful experimental model to study angiogenesis and to stimulate vascularization in reconstructed human skin. Because it is human-derived, it is in our opinion the safest of all available types of skin equivalent. Having epidermal and dermal structures, it can be used in one-stage grafting procedures for wound closure.

Processing efficacy in relation to microbial contamination of skin allografts from 723 donors.

The Siena Skin Bank, established in 2000, processes skin from more than 130 cadaveric donors per year (about 400,000 cm(2)) and distributes it for transplants to treat burns and other types of skin loss. More than 1,500,000 cm(2) of homologous skin has been transplanted to date. At the Siena Skin Bank we conducted a retrospective study of our data to assess microbial contamination of skin specimens from 723 donors banked in the period 2000-2007. Our aim was to determine factors deleterious for skin quality, to optimize skin banking procedures and to reduce corrective actions. The factors analyzed were: type of donor (multi-organ, multi-tissue, live or cadaver), cause of death, time elapsing between death and procurement, different procurement centres and operator experience. Of the 723 donors considered, 26.55% (192/723) were positive for microbes, 22.68% (164) for bacteria and 5.39% (39) for mycetes. Of these 192 positives, 82 (42.70%) required corrective actions. The data obtained showed that the only variables significantly affecting microbial contamination of tissue were type of donor (live or cadaver) and type of processing (cryo- or glycerol preservation).

Anaphylactoid reaction to intravenous sodium ferric gluconate complex during pregnancy.

We report the first case of a severe anaphylactic or anaphylactoid reaction to sodium ferric gluconate complex in a pregnant patient. Sodium ferric gluconate complex is felt to be one of the safest forms of iron therapy during pregnancy. This case highlights the need for extreme caution and vigilance in pregnant patients receiving any type of parenteral iron therapy.