Rectal peptic ulceration—A rare cause of rectal bleeding

Analysis of the 27 cases of heterotopic gastric mucosa reported in the literature and a new case described here elucidates the main features of this disease: 1) all but one asymptomatic case were diagnosed in infants or in adults under 26 years old; 2) although rectal bleeding occurred in 24 patients, rectal peptic ulceration was found in only 13; 3) six of the patients also had rectal duplication; and 4) 19 times the limited extension of the heterotopic gastric mucosa was compatible with a complete excision by a transanal approach.     

A new type of congenital dysfibrinogenaemia with defective fibrin lysis—Dusard syndrome: possible relation to thrombosis

S ummary . Congenital dysfibrinogenaemia is described in three members of a family presenting with recurrent thrombosis and in two other young members not yet affected. An abnormality in the polymerization of fibrin monomers was noted. In addition, the pathological fibrin clots were found to be less sensitive to degradation by a post venous occlusion euglobulin solution than normal fibrin. After fibrin clot incubation with lys-plasminogen at different concentrations, the biological activity of plasminogen in patient fibrin clot on S 2251 after SK-addition, was less than that observed with normal fibrin. It is speculated that defective in vivo thrombolysis might explain the recurrent thrombosis observed in this family. This finding represents a new concept in understanding thromboembolic diseases.     

Vitamin A abuse: development of cirrhosis despite cessation of vitamin A. A six-year clinical and histopathologic follow-up

ABSTRACT— We report the case of a 35-year-old man who contracted vitamin A-induced liver cirrhosis. Five years before, he had been investigated for vitamin A-induced non-cirrhotic portal hypertension. In this case, the clinical and histopathologic evolution from non-cirrhotic portal hypertension to cirrhosis was documented. In spite of the cessation of pharmaceutical vitamin A intake, the disease progressed. Therapy with colchicine and phenobarbital apparently did not influence evolution to cirrhosis. This suggests that vitamin A can trigger largely unknown mechanisms of liver fibrosis which seem to be self-perpetuating.     

Endothelin is a dose-dependent trophic factor and a mitogen in small arteries in vivo

OBJECTIVE: Endothelin (ET) modulates cellular processes relevant to vascular remodeling, but there is still some debate as to the potential of ET to be a trophic factor or a mitogen. Moreover, the signaling of ET in vivo to produce these effects is largely unknown. METHODS: 3H-leucine and 3H-thymidine incorporation in rat small mesenteric arteries was studied with several doses of ET-1 (0.1-10 pmol/kg/min) administered for 26 h in vivo. RESULTS: The EC50 for protein synthesis was four times lower than that of DNA synthesis, with maximal effects around 1 and 3 pmol/kg/min, respectively. At 5 pmol/kg/min, ET enhanced CDK2 activity by reducing the binding of its inhibitor p27(Kip1). In contrast, the binding was enhanced at 0.5 pmol/kg/min. The reduced binding observed at 5 pmol/kg/min could not be explained by changes of p27(Kip1) or CDK2 content. Phosphorylation of p27(Kip1) on serine 10 was significantly reduced at 5 pmol/kg/min ET. Although the phosphoinositide 3-kinase pathway was activated, it did not contribute to the protein or DNA synthesis responses. Administration of 1 or 5 pmol/kg/min ET-1 for 28 days increased the thickness and cross-sectional area of the small mesenteric artery due to hypertrophy and hyperplasia, respectively, thus confirming the results obtained in acute conditions. CONCLUSION: ET modulates p27(Kip1) binding to CDK2, producing hypertrophy at low and hyperplasia at higher concentrations. Taken together, these results suggest that ET can act both as a trophic factor and as a mitogen in an in vivo environment, depending on its local concentration.     

Differences in oxidative stress dependence between gastric adenocarcinoma subtypes

AIM:To investigate the extent of oxidative stress in pre-neoplastic and neoplastic gastric mucosa in relation totheir pathological criteria and histological subtypes.METHODS:A total of 104 gastric adenocarcinomas from98 patients(88 infiltrative and 16 intraepithelial tumors)were assessed immunohistochemically for expression ofiNOS and occurrence of nitrotyrosine(NTYR)-containingproteins and 8-hydroxy-2'-deoxyguanosine(8-OH-dG)-containing DNA,as markers of NO production anddamages to protein and DNA.RESULTS:Tumor cells staining for iNOS,NTYR and8-OH-dG were detected in 41%,62% and 50% ofinfiltrative carcinoma,respectively.The three markerswere shown for the first time in intraepithelial carcinoma.The expression of iNOS was significantly more frequentin tubular carcinoma(TC)compared to diffuse carcinoma(DC)(54% vs 18%;P=0.008)or in polymorphouscarcinoma(PolyC)(54% vs 21%;P=0.04).NTYRstaining was obviously more often found in TC thanthat in PolyC(72% vs 30%;P=0.03).There was atendency towards a higher rate of iNOS staining whendistant metastasis(pM)was present.In infiltrativeTC,the presence of oxidative stress markers was notsignificantly correlated with histological grade,density ofinflammation,the depth of infiltration(pT),lymph nodesdissemination(pN)and pathological stages(pTNM). CONCLUSION:The iNOS-oxidative pathway may playan important role in TC,but moderately in PolyC and DC.DNA oxidation and protein nitration occur in the threesubtypes.Based on the significant differences of NTYRlevels,TC and PolyC appear as two distinct subtypes.