Acta Gastro-Enterologica Belgica最新文献

Barrett's oesophagus is known as one of the most important risk factor of oesophageal adenocarcinoma. Because of the increasing incidence of these latter, many endoscopic methods such as argon plasma coagulation, photodynamic therapy or endoscopic mucosal resection are now in evaluation in order to eradicate Barrett's oesophagus or to treat dysplasia and early cancers arising from this metaplasia. The aim of this paper is to comment these techniques and discuss their usefulness.

The authors first briefly review how the concept of COX-2 selectivity was brought to light, then tested against the known gastrotoxicity ranking of currently used NSAIDs, from the old classics to the most recent. One truly selective COX-2 agent--celecoxib--is now being marketed in an ever increasing number of countries. So far it seems to keep its main promises, i.e. high--albeit not total--safety regarding gastrointestinal adverse effects, and undisturbed platelet function. Association with warfarin drugs seems to raise no problems, but one should still be wary of possible renal side-effects. Efficacy, at least as assessed in osteoarthritis and rheumatoid patients, appears satisfactory. However, treatment of intense inflammatory crises, such as gout or ankylosing spondylitis, has not been assessed, as yet. Another COX-2 agent--rofecoxib--is on the brink of being released. Its even more potent COX-2 selectivity raises new issues. What about some COX-1 activity that several authors detected in rheumatic synovitis? On the other hand, in particular circumstances, organs such as the stomach, the kidney and small blood vessels, seem to have their homeostasis partly controlled by COX-2 mechanisms also. These questions should be answered soon, whilst clinical experience with the COX-2 agent builds up.

A case of a thirty-nine year old woman with cerebral cavernous angiomas who developed anaemia and thrombocytopenia secondary to diffuse liver angiosarcoma is reported. This unique association of liver angiosarcoma and cerebral cavernous angiomas may suggest that this tumour may potentially develop from benign vascular lesions. Hematologic abnormalities in angiosarcomas are moreover reviewed based on recent literature search.

Several advances have been produced in the diagnosis and treatment of patients with hepatocellular carcinoma. It is possible to diagnose the neoplasm at an early stage when radical treatment options may be applied. The criteria to apply them successfully have been refined and the expected outcome has been improved, but we still lack a useful treatment for the vast majority of patients who are still diagnosed at an advanced stage. Efforts have to be done during the next years to develop such an option (perhaps based on gene manipulation) and until then the management of this tumour will still constitute a challenge for physicians taking care of patients with this neoplasm.

The discovery of the HFE gene has improved classification and diagnosis of iron overload. Most patients with a phenotypic diagnosis of haemochromatosis are homozygote for the C282Y mutation. Among those with other genotypes, only compound heterozygotes, who present the C282Y mutation on one chromosome and the H63D on the other, may present with haemochromatosis, but with a low penetrance and a mild expression. Other patients usually present with another cause of iron overload, such as insulin resistance, alcoholic liver disease or liver cirrhosis. The practical management of haemochromatosis has been greatly modified, since liver biopsy is no more necessary for diagnosis in C282Y homozygotes, and is only needed for exclusion of cirrhosis. Family screening has also greatly benefited from genotyping.

In this experimental study, the prophylactic effects of Gingko-Biloba Extract (GBE) were examined after experimental ischemia on intestinal wall damage. 50 Wistar-Albino rats (2.5 month old) were gathered and separated into 5 groups (n:10). Group 1 was subjected to a laparotomy (sham-operated group) whereas all other experimental groups were subjected to an occlusion of their superior mesenteric arteries for 30 minutes and a period of 20 minutes reperfusion following occlusion. Group 2 was not given any prophylactic agent during the experiment (untreated control group). GBE was administered in a dosage of 50 mg/kg (i.v.) as a prophylactic agent to Group 3 one hour prior to laparotomy whereas Group 4 was given GBE at 50 mg/kg (i.v.) just before ischemia. Group 5 was given GBE in the same dosage just before reperfusion. Immediately after reperfusion, a biopsy was taken from the ileum (10 cm proximity to ileocaecal valve) for histopathological assessment. A significant prophylactic effect of GBE was observed in Group 5 in which GBE was administered just before reperfusion.

Cancer is a genetic disease. The unstable genome of cancer cells causes tumour progression through multiple alterations in suppressor and promoter genes, leading to loss of homeostatic and gain of oncogenic functions. Invasion is the critical step in the acquisition of malignancy. It implicates a continuous molecular conversation of the cancer cells with other cells and with the extracellular matrix in which adhesion molecules are crucial. One of these, E-cadherin, is discussed in the present review. E-cadherin is a transmembrane glycoprotein that forms a complex with cytoplasmic proteins, termed catenins because they link E-cadherin to the actin cytoskeleton. E-cadherin/catenin-mediated intercellular adhesion and communication is mainly homophylic homotypic. There is compelling evidence from experiments in vitro as well as in vivo to accept that the E-cadherin/catenin complex acts as an invasion suppressor. The mechanism of this action is not only through cell-cell adhesion but also through transduction of signals to the cell's motility system. In the replication error positive human colon cancer cell line HCT-8, the alpha E-catenin gene CTNNA1 is an invasion suppressor gene. Here, the transition from the non-invasive to the invasive state was prevented by introduction into the unstable non-invasive cells of either an extra CTNNA1 or a wild type hMSH6 mismatch repair gene. beta-catenin also participates at a complex which comprises the adenomatous polyposis cancer protein APC. In colorectal cancer, mutation of either APC or beta-catenin is oncogenic. Downregulation of the E-cadherin/catenin complex may occur in several ways amongst which are gene mutations, methylation of 5'CpG dinucleotides within the promotor region of E-cadherin, tyrosine phosphorylation of beta-catenin, cell surface expression of proteoglycans sterically hindering E-cadherin and proteolytic release of fragments from the extracellular part of E-cadherin. Upregulation of the E-cadherin/catenin complex has been realized with a series of agents, some of which can be used therapeutically. In most human gastrointestinal cancers the E-cadherin/catenin or related complexes are disturbed and this underscores their pivotal role in the progression of these tumours. Mutations of the E-cadherin gene, including germline mutations, occur in diffuse gastric carcinoma, CpG methylation around the promotor region of E-cadherin in hepatocellular carcinomas and mutations of the APC tumour suppressor gene or in the beta-catenin oncogene in most colorectal cancers. The literature agrees about the disturbance of immunohistochemical patterns of E-cadherin and catenin expression in gastrointestinal cancers. Conflicting opinions do, however, exist about the prognostic value of such immunohistochemical aberrations. We doubt that immunohistochemistry of E-cadherin or catenins add prognostic value to the already used histological grading systems. In our opinion the major benefit from understanding

Ascaris lumbricoides is the most frequent human helminthic parasite. Usually human ascariasis is poorly symptomatic but complications can arise due to worm migration. Erratic worm migration into the biliary tree is a rare but threatening condition regarding the associated complications: cholecystitis, pancreatitis, obstruction of bile ducts, liver abcesses and recurrent pyogenic cholangitis. We describe a case of a young belgian women suffering from recurrent biliary colics over a period of eight months with repeated normal ultrasound findings. ERCP proved being the only effective diagnostic procedure for a living biliary worm, which was successfully removed with a balloon catheter.