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This short communication describes how some Mexican tissue banks have established their own system for coding and traceability of tissues.

Knowledge about transplants in Mexico goes back to the Aztec period. Today the need for organ and tissue transplants in Mexico is high; the estimated number is 100,000 patients, but there are only 2 donors per million population, for corneas. The organ, tissue and cell transplantation law which was modified in 2,000, establishes that when a person dies, he will be a potential donor of organs and tissues. This new law will give hope to many patients, since it is expected to increase significantly the amount of organs and tissues for transplants. At present Mexico has 178 hospitals that are authorized to carry out organ and tissue transplants, and 53 Tissue Banks.

A description of the successful use of a fetal membrane in the recovery of a injured patient is presented. A diabetic female patient, 63 years old, was accidentally injured with a winnowing fork, which opened the skin of the front side of her left foot. For first two weeks, she was submitted to a treatment involving antibiotics, analgesics and antiinflammatories, but the infection did not disappear and the pain was almost unbearable. At the end of the third week, the injury underwent surgical washing with epidural blockage; suitable insulin dose and oral antidiabetics controlled the high-glucose concentration. However, due to the intensity of the pain, a risky epidural blockage was administered every four hours for 12 days. Finally, a radiosterilised human fetal membrane, which was collected at HCSAE and processed at ININ, was used as a biological wound dressing. Biological control of the tissue was performed at Facultad de Química de la Universidad Nacional Autónoma de México (The Chemistry Faculty of the National Autonomous University of Mexico) (UNAM). As a result, the pain first diminished and then stopped. The healing process started in a few days and led to a complete recovery in 2 1/2 months. At present, the patient is in good condition, living a normal life.

The cases of two patients with burns treated with dermis allograft and of one patient for lip reconstructive aesthetic filling treated with less than one mm3 of radiosterilised acellular dermis are presented. This paper emphasizes the treatment with radiosterilised dermal grafts with a permanent character so far. Hospitals, therefore, can satisfy the demand for this kind of tissue in the case of disaster and patients with serious injuries. In the cases cited, histocompatibility analysis was not required, thus having the advantage of long-time storage of the radiosterilised dermis used on these patients. Neither inflammatory reaction nor acute phase re-absorption were observed. Moreover, shrink (contract) healing was diminished. After two years, the results are still satisfactory.

The case of a patient with dystrophic epidermolysis bullosa treated with radiosterilised amniotic membranes is presented. The disorder is a congenital disease characterised by a poor desmosomal junction in the keratinocyte membrane. After proper donor screening, amnios were collected at Hospital Central Sur de Alta Especialidad (HCSAE), PEMEX and microbiological analysis was performed at Universidad Nacional Autónoma de México, FQUNAM, (Biology Dept. of the Chemistry Faculty, National Autonomous University of Mexico), before and after radiation sterilisation. Processing, packaging and sterilisation were performed at Instituto Nacional de Investigaciones Nucleares, ININ, (National Nuclear Research Institute). The patient, a ten-year-old boy with severe malnutrition, extensive loss of skin and pseudomonad infection in the whole body, was treated with gentle debridement in a Hubbard bath. Later amnion application was performed with sterilised amnios by using two different processes, in one of which the amnion was sterilised with paracetic acid, preserved in glycerol, kindly donated by the German Institute for Tissue and Cell Replacement and applied by Dr. Johannes C. Bruck, IAEA visiting expert, and the other amnion was processed at ININ: air dried and sterilised by gamma radiation at dose of 30 kGy. After spontaneous epithelisation was successfully promoted for seven days, the pain was alleviated and mobility was improved in a few hours and the patient's general condition was so improved that in a month he was discharged. Unfortunately, because this disease is revertive and has malignant degeneration, the prognosis is not good.