Norihiro Ban

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The "congestion index" is used to mean the ratio between the cross-sectional area (cm2) and the blood flow velocity (cm/sec) of the portal vein, as determined by a duplex Doppler system. The indices as determined in normal subjects and patients with liver disease were as follows: normal subjects (n = 85), 0.070 +/- 0.029 cm X sec; acute hepatitis (n = 11),(More)
Mice with a targeted mutation of the gastric inhibitory polypeptide (GIP) receptor gene (GIPR) were generated to determine the role of GIP as a mediator of signals from the gut to pancreatic beta cells. GIPR-/- mice have higher blood glucose levels with impaired initial insulin response after oral glucose load. Although blood glucose levels after meal(More)
The goal of this study was to demonstrate that glutathione S-transferase (GST)-pi is directly involved in the intrinsic and acquired resistance of cancer cells to anticancer drugs. To this end, GST-pi antisense cDNA was transfected into the cultured human colon cancer cell line M7609, which expresses an innately high level of GST-pi and shows intrinsic drug(More)
We analyzed a mechanism of transcriptional regulation of the human insulin gene by cyclic AMP response element modulator (CREM) through four cyclic AMP response elements (CREs). We isolated two novel CREM isoforms (CREMDeltaQ1 and CREMDeltaQ2), which lack one of the glutamine-rich domains, Q1 and Q2 respectively, and six known isoforms (CREMtaualpha,(More)
The biological responses of the transforming growth factor beta (TGF-beta) superfamily are induced by activation of a receptor complex and Smad proteins. We surveyed the TGF-beta superfamily receptors using the degenerate PCR strategy, and found activin receptor-like kinase 7 (ALK7) to be abundantly expressed in fetal rat pancreatic islets. ALK7 is also(More)
The ultrasonic duplex system, which is composed of a pulsed Doppler flowmeter and a linear array B-mode scanner, was developed for the purpose of quantitative transcutaneous measurement of blood flow. It was applied here to the study of portal blood flow in a normal series with healthy volunteers as subjects. A preliminary experiment, prepared by setting up(More)
To measure volume blood flow quantitatively in human abdominal arteries, we used an ultrasonic image-directed Doppler system and electromagnetic flowmeter to first measure volume flow in canine arteries. In dogs, there was a strong linear correlation (R = 0.98) between the product of the time average of the maximum blood flow velocity and the average(More)
Insulin plays a crucial role in the regulation of glucose-homeostasis, and its synthesis is regulated by several stimuli. The transcription of the human insulin gene, enhanced by an elevated intracellular concentration of calcium ions, was completely blocked by Ca2+/calmodulin-dependent protein kinase inhibitor. The activity of the transcription factor(More)
We have shown recently that oxidative stress by chronic hyperglycemia damages the pancreatic beta-cells of GK rats, a model of non-obese type 2 diabetes, which may worsen diabetic condition and suggested the administration of antioxidants as a supportive therapy. To determine if natural antioxidant alpha-tocopherol (vitamin E) has beneficial effects on the(More)
Portopulmonary venous anastomosis is a potential channel for systemic arterial embolization during embolization procedures for bleeding esophageal varices. To document the presence of such anastomoses, 15 patients with esophageal varices were studied by real-time contrast echocardiography combined with transhepatic cineportography. Cinefluorographic(More)