Palmoplantar keratoderma and oral leucoplakia with cutaneous horn of the lips.

The inherited palmoplantar keratodermas (PPK) may be associated with a wide variety of other ectodermal abnormalities. The coexistence of PPK and leucoplakia may indicate the increased risk of oesophageal carcinoma in adult life. Cutaneous horn may develop over benign, precancerous, as well as malignant lesions, and frequently may be associated with actinic keratoses and Bowen's disease. On the other hand, the relationship of cutaneous horn and leucoplakia has been the subject of only a single case report. We present a case of PPK and diffuse oral leucokeratosis associated with relapsing cutaneous horn of the lips.

Tracheal reconstruction with porous high-density polyethylene tracheal prosthesis.

The variety of methods used for the treatment of severe tracheal stenosis and the occasional failure to obtain lasting and consistent relief are measures of the difficulty of the problem. Presently, several surgical approaches are used for reconstructing large defects of the cervical trachea, reminding us that no single technique has gained wide clinical acceptance. We resected a U-shaped cartilage from 6 to 8 rings of the trachea of 10 New Zealand rabbits. We used a porous high-density polyethylene (PHDP) prosthesis to reconstruct the cervical trachea, and did not perform a tracheotomy during this operation. We followed up the rabbits for 4 to 10 months. One of the rabbits died in the second month because of respiratory distress; another was lost in the fourth month of the study while delivering young. The others continued to thrive; in fact, one of them gave birth 3 times after our study and was well able to take care of her young. At the end of the study, the rabbits were painlessly sacrificed in order to remove the larynx and trachea and examine them histopathologically. In the histopathologic examinations, the prostheses were incorporated into the native trachea and adhered to the surrounding organs, especially to the esophagus. No mucosal irregularities were seen on the surface of the prosthesis, and all the surfaces appeared to be covered with ciliated pseudostratified epithelium. This tracheal prosthesis provides good results in rabbit tracheal reconstruction, and appears very promising for the clinical repair of tracheal defects.

Neurotoxicity of midazolam in the rabbit.

Safe and efficient use of spinal drugs requires neurotoxicologic animal studies before ethical application. We have evaluated the neurotoxicologic interruptions of intrathecal administration of midazolam in rabbits. Eighteen white New Zealand rabbits were randomly assigned into three groups consisting of six rabbits each. In conscious animals, 0.3 ml 0.9% normal saline solution, 0.3 ml 0.1% midazolam (Roche, Dormicum) or 0.3 ml preservative free midazolam were intrathecally administered. Light and fluorescence microscopy evaluations were performed on transverse spinal cord sections by a neurohistopathologist in a blind fashion. Midazolam and preservative free midazolam treated rabbits showed significant histologic changes in light and fluorescence microscopy. The histologic and vascular lesions with the use of midazolam and preservative free midazolam suggested neurotoxic effects; thus chronic intrathecal administration of midazolam should be avoided in humans.

The role of leucocyte-derived free oxygen radicals in the pathogenesis of experimental acute pancreatitis.

The role of free oxygen radicals in experimental acute pancreatitis induced by common bile duct ligation was investigated by measuring malondialdehyde levels in the rat pancreas. Also, the potential role of leucocytes as the source of free oxygen radicals was tested by inducing leukopenia with methotrexate. The malondialdehyde levels in the control, pancreatitis and pancreatitis + methotrexate groups were 9.6 +/- 2.0, 44.8 +/- 11.4, and 25.6 +/- 5.0 nmol malondialdehyde/ g pancreas tissue respectively. The corresponding histopathological severity scores were 0.5 +/- 0.7, 8.1 +/- 1.2 and 3.7 +/- 1.1. The results suggest that the leucocyte may be an important source of free oxygen radicals in this experimental model.

Nucleolar organizing regions in the operated rat stomach: relationship to metaplasia, dysplasia and carcinoma.

This study investigated the role of duodenogastric reflux in rats after antecolic gastrojejunostomy. At the end of the study, adenocarcinoma was present in 43 per cent, dysplasia in 14 per cent and intestinal metaplasia in 43 per cent of animals. No such changes were found in control rats. A technique for silver staining nucleolar organizing regions (AgNORs) was applied to these lesions and to the control group. The AgNOR count gradually increased from normal gastric mucosa to carcinoma. This technique demonstrated differences in AgNOR count between normal mucosa and other lesions (adenocarcinoma, dysplasia, intestinal metaplasia) (P < 0.001). There was, however, considerable overlap among adenocarcinoma, dysplasia and metaplasia (P > 0.1).