Studies of the pathogenesis of hepatic encephalopathy are hampered by the lack of a satisfactory animal model. We examined the neurological features of rats after bile duct ligation fed a hyperammonemic diet (BDL؉HD). Six groups were studied: sham, sham pair-fed, hyperammonemic, bile duct ligation (BDL), BDL pair fed, and BDL؉HD. The BDL؉HD rats were made hyperammonemic via an ammonia-containing diet that began 2 weeks after operation. One week later, the animals were sacrificed. BDL؉HD rats displayed an increased level of cerebral ammonia and neuroanatomical characteristics of hepatic encephalopathy (HE), including the presence of type II Alzheimer astrocytes. Both BDL and BDL؉HD rats showed activation of the inflammatory system. BDL؉HD rats showed an increased amount of brain glutamine, a decreased amount of brain myo-inositol, and a significant increase in the level of brain water. In coordination tests, BDL؉HD rats showed severe impairment of motor activity and performance as opposed to BDL rats, whose results seemed only mildly affected. In conclusion, the BDL؉HD rats displayed similar neuroanatomical and neurochemical characteristics to human HE in liver cirrhosis. Brain edema and inflammatory activation can be detected under these circumstances. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html). H epatic encephalopathy (HE) is a severe neuropsychiatric complication in both acute and chronic liver failure. Although the pathophysiology of this disorder is incompletely understood, there is agreement on the important role of neurotoxins in its development, especially ammonia. 1 Neuropathologically, HE in chronic liver disease is characterized by astrocytic rather than neuronal changes. 2 Histopathology studies of brain sections from patients with cirrhosis who died in hepatic coma show the presence of changes known as Alzheimer type II astrocytosis. These astrocytes display a specific characteristic of swollen cytoplasm containing a large pale nucleus, with prominent nucleolus and patches of heterochromatin associated with the nuclear envelope. 2 Recently, a new pathophysiological hypothesis has been developed, emphasizing the role of low-grade brain edema in the pathogenesis of HE in chronic liver disease. 3 Following this theoretical model, the presence of a lowgrade astrocyte swelling could have important functional consequences despite the absence of clinically overt increases of intracranial pressure. 3

The hind limbs of six dogs were reimplanted immediately after amputation. Another nine were conserved by extracorporeal circulation for 24 h, and then examined histologically. A further six were conserved by the same method and then reimplanted after 24 h. Conservation by extracorporeal circulation maintained the limbs in good condition. Less than 5% of the muscle fibres showed abnormality when examined, and the lesions were reversible.

La úlcera péptica (UP) consiste en una pérdida de sustancia de la superficie interna del tracto digestivo que alcanza al menos en profundidad la s u b m u c o s a 1. Puede aparecer en el tercio inferior del esófago, estómago, bulbo duodenal y menos frecuentemente en la segunda porción del duodeno y yeyuno proximal. Aproximadamente un 5-10% de los adultos en países desarrollados padecen una UP en algún momento de su vida 1-3. En España se ha estimado que un 10% de la población padecerá una UP 2. La prevalencia de la UP se ha estimado en un 1% y la incidencia en un 0,1-0,3% anual 1-3. La úlcera duodenal (UD) es unas 3-4 veces más frecuente que la úlcera gástrica (UG). RESUMEN La úlcera péptica (UP) tiene una alta pre v a l e ncia e incidencia. Se ha estimado que un 10% de la población española padecerá una UP. La infección por Helicobacter pylori (HP) y el consumo de antiinflamatorios no esteroideos (AINE) son las principales

No abstract