Biomedical subjects

I Ohashi

Publications and source records attributed to I Ohashi.

57 records · Page 4Linked to original sources

PubMedDate not supplied

Aberrant left gastric vein demonstrated by helical CT.

PURPOSE: Our goal was to describe the CT findings of aberrant left gastric vein (ALGV) and to evaluate the clinical significance of this vein. METHOD: Four patients in whom ALGVs were demonstrated by helical CT were examined. Each patient had either intrahepatic cholangiocarcinoma, cirrhosis with gastric varices, chronic hepatitis, or nonspecific abdominal pain. All patients underwent two phase helical CT, and the patient with cholangiocarcinoma underwent CT during arterial portography, and 3D images of the abdominal veins were obtained. RESULTS: In all patients, the ALGVs ran along the hepatogastric ligament and were directly connected with the left portal branch. In the patient with cholangiocarcinoma, the portal vein had severe stenosis by tumor invasion, and both the ALGV and the aberrant right gastric vein functioned as a collateral pathway of the portal flow into the liver. In the patient with cirrhosis, dilated ALGV with hepatofugal flow caused gastric varices. CONCLUSION: The ALGV is directly connected with the left portal branch and may play an important role in the collateral pathway of the portal system.

Aged↗

PubMedDate not supplied

Increased heme oxygenase-1 gene expression in the livers of patients with portal hypertension due to severe hepatic cirrhosis.

Surgical bleeding associated with splanchnic hyperaemia due to portal hypertension complicates the anaesthetic management of hepatic transplantation. Although the mechanism(s) of portal hypertension are not fully understood, carbon monoxide, a product of the heme oxygenase (HO) reaction, is thought to be one of the endogenous vasodilators in the liver. In this study, the expression of mRNA encoding inducible HO isozyme (HO-1) in the livers of patients with portal hypertension undergoing hepatic transplantation was determined in comparison with those without portal hypertension. HO-1 mRNA levels were significantly greater in the portal hypertension group than in the group without portal hypertension. In contrast with HO-1, the gene expression of non-specific delta-amino-levulinate synthase (ALAS-N), which is down-regulated by heme in the liver, was the same in both groups. These results suggest that HO-1 is up-regulated through heme-independent stimuli according to the development of portal hypertension, and that induced HO-1 plays a pathophysiological role in portal hypertension through carbon monoxide production.

Adult↗

PubMedDate not supplied

Electromagnetic fields inhibit endothelin-1 production stimulated by thrombin in endothelial cells.

Electromagnetic field (EMF) radiation has been found to induce arteriolar dilatation, but the mechanism of action remains largely unknown. This study investigated the effect of EMF radiation on the production of endothelin-1 (ET-1), a potent vasoconstrictor, by cultured endothelial cells. EMF radiation reduced ET-1 basal levels in human umbilical vein and microvascular endothelial cells, but failed to reduce ET-1 basal levels in bovine and human aortic endothelial cells. EMF radiation significantly inhibited thrombin-stimulated ET-1 production in all four endothelial cell types in a dose-dependent manner. EMF radiation significantly inhibited thrombin-induced endothelin-1 mRNA expression in all four cell types. The inhibitory effect of EMF radiation on ET-1 production was abolished by the nitric oxide synthase inhibitor NG-monomethyl-L-arginine (10(-3) mol/1). These results demonstrate that EMF radiation modulates ET-1 production in cultured vascular endothelial cells and the inhibitory effect of EMF radiation is, at least partly, mediated through a nitric oxide-related pathway.

Animals↗