Ondine curse and neurocristopathy

Two newborns, 1 male and 1 female, had both Ondine curse, also known as congenital, central hypoventilation syndrome, and Hirschsprung disease. Both infants demonstrated insufficient respiration while asleep and normal respiration when awake. The lesser affected child had an otherwise normal neurologic examination, but suffered from seizures. He died at 18 months of age; neuropathologic examination of the brain was unremarkable. The girl had a severe and ultimately fatal form of this disorder and manifested a variety of neurologic abnormalities indicative of developmental failure of the neural crest-derived tissues. These abnormalities included unreactive pupils and deafness. She died at 40 days of age; autopsy permission was denied. The etiology of sleep apnea is not known. Mechanisms of central integration may be abnormal but the association with neural crest maldevelopment implicates the peripheral nervous system.     

Treatment of duplicated thumb using a ligamentous/periosteal flap

Since 1975, 22 duplicated thumbs in 21 children were treated by ablation of one of the digits, elevation of a ligament and periosteal flap from the proximal bone, reduction osteotomy to narrow the widened proximal bone, centralization of the retained thumb, and stabilization of the joint by reattaching the ligament and periosteal flap. In addition to improving the cosmetic appearance by centralizing the retained thumb on the narrowed proximal bone, good joint stability was provided. Three patients had subsequent joint arthrodesis because of laxity of the contralateral collateral ligament. The procedure is preferred to the reconstruction of a single digit by using component parts of both duplicated thumbs because the described procedure is technically simpler and does not potentially interfere with physeal growth or leave a nail matrix defect.     

Tannic acid-induced nucleolar changes in hepatocytes transplanted into syngeneic or xenogeneic host and in hepatocytes maintained in primary culture

In this study we have investigated the effect of a single dose of tannic acid, administered s.c., on the nucleolar ultrastructure of hepatocytes transplanted into a syngeneic or xenogeneic host in order to evaluate the validity of our hepatocyte transplantation system as an in vivo alternative to the use of whole animals to test for species and strain differences to the effects of hepatotoxins. Within 4-6 h following tannic acid injection, rat hepatocytes transplanted into the anterior chamber of eye and inguinal fat pads of rat and athymic nude mouse, showed changes of nucleolar components, with separation of ribonucleoprotein containing granules into discrete dark zones. These dark areas were surrounded by light areas consisting of granular and fibrillar components of the nucleolus. These changes were identical to tannic acid-induced nucleolar alterations in the homotopic liver. Hamster and rat hepatocytes xenotransplanted into athymic nude mice also displayed prominent nucleolar alterations in response to tannic acid. The similarity and extent of nucleolar alterations observed in transplanted hepatocytes and the in situ homotopic liver cells attest to the usefulness of the hepatocyte transplantation system for the evaluation of species differences in biological response to toxic/carcinogenic effects of xenobiotics.