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Notes: It has been suggested that CN (calcineurin, protein phosphatase-2B) regulates signal transduction, particularly in various secretory cells. In this study, we examined whether CN plays a role in stimulus-secretion coupling of gastric parietal cells.〈section xml:id="abs1-2"〉〈title type="main"〉Materials and methods:Localization of CN in gastric epithelial cells was examined immunohistochemically. The role of CN in the acid secretion pathway of gastric parietal cells was assessed by evaluating the effect of FK506, a specific inhibitor of CN, on gastric acid secretion in pylorus-ligated rats. In addition, the effect of FK506 on secretagogue (carbachol, tetragastrin and histamine)-stimulated acid secretion was investigated in lumen-perfused rats.〈section xml:id="abs1-3"〉〈title type="main"〉Results:CN was specifically expressed in gastric parietal cells and chief cells of the gastric mucosal epithelium immunohistochemically. FK506 dose-dependently inhibited gastric acid secretion in pylorus-ligated rats. In lumen-perfused rats, FK506 completely inhibited acid secretion prestimulated by carbachol and tetragastrin, agonists known to increase cytosolic Ca2+, but did not affect acid secretion prestimulated by histamine.〈section xml:id="abs1-4"〉〈title type="main"〉Conclusions:Our findings demonstrate that FK506 has a potent antisecretory effect in parietal cells through inhibition of only Ca2+-mediated acid secretion pathways. As FK506 is known to specifically inhibit CN, which plays an important role in signal transduction in various secretory cells, protein dephosphorylation signalling might also be crucial for gastrin and M3 muscarine receptor-mediated stimulation of proton pump.

Notes: Abstract Asymptomatic macroscopic portal-hepatic venous shunt (MPVS) without chronic hepatic disease is a rare vascular lesion. Two cases of this disorder are reported, and the usefulness of color Doppler sonography for studying hemodynamics of such small vascular lesions is stressed.

Notes: Abstract. Portal hypertension is a relatively uncommon pathologic condition in children and young adults in contrast with older adults. The aim of this study is to evaluate the utility of sonography and color Doppler sonography in the diagnosis of portal hypertension in children and young patients and to evaluate the sonographic pattern of each disease. We reviewed 25 such patients who were younger than 30 years old and obtained the following sonographic findings: (1) liver cirrhosis: (a) multiple intrahepatic venovenous shunts in patients with primary Budd-Chiari syndrome and (b) intrahepatic vascular narrowing and nodular coarse parenchymal texture, with multiple very-high-echo spots along the portal vein in patients with Wilson disease; (2) congenital hepatic fibrosis: marked and developed collaterals, wide periportal echogenic band, and a heterogeneous parenchymal texture comprised of multiple high echoes but without portal thrombus; and (3) extrahepatic portal thrombosis: invisible portal lumen except as an echogenic band. Sonography and color Doppler sonography are very useful in diagnosing these portal hypertensive diseases. However, there are no specific sonographic findings, and the role of sonography is limited to follow-up observation of associated secondary hepatobiliary changes in patients with congenital biliary atresia.

Notes: Abstract. Background: Compared with esophageal varices, gastrointestinal varices are relatively rare, but they are clinically important because they tend to bleed massively. Color Doppler sonography is now widely used to diagnose the collaterals, but few color Doppler findings of gastric or intestinal varices have been reported. The aim of this study was to investigate the sonographic and color Doppler findings of gastrointestinal varices and to determine the role of color Doppler sonography in the diagnosis of these varices. Methods: We studied 30 patients who were diagnosed by endoscopy as having gastrointestinal varices (24 gastric, four duodenal, two intestinal) with color Doppler sonography and compared the results with the clinical data. The causes of gastric varices included liver cirrhosis (16/24, 66.7%), idiopathic portal hypertension (3/24, 12.5%), chronic pancreatitis with splenic vein thrombosis (2/24, 8.3%), congenital biliary atresia (1/24, 4.2%), congenital hepatic fibrosis (1/24, 4.2%), and unknown (1/24, 4.2%). The causes of duodenal varices included idiopathic portal hypertension with portal thrombosis (3/4, 75%) and liver cirrhosis (1/4, 25%). Results: The gastric wall at the fundus was thickened in 17 of 24 cases (70.8%) with gastric varices, and the duodenal wall was thickened in four of four cases (100%) with duodenal varices. Sonography revealed thrombosis in the splenic vein in two of two cases with gastric varices secondary to chronic pancreatitis and in the confluence of the superior mesenteric vein and the splenic vein in three of four cases with duodenal varices. Color Doppler sonography demonstrated multiple, slow constant blood flows in the thickened wall in 15 of 24 cases (62.5%) with gastric varices and in four of four cases (100%) with duodenal varices. It demonstrated accumulated slow constant blood flows in the cecum in the case with cecal varices. Color Doppler showed also the communication between the varices and the neighboring vascular system (superior mesenteric vein and inferior vena cava) in the case with cecal varices, but it did not directly reveal such a communication in the other 29 cases (96.7%). Color Doppler showed a hepatofugal flow in the left gastric vein in all the hemorrhagic gastric varicose patients with esophageal varices, but it showed a hepatopetal flow in the left gastric vein in the isolated nonhemorrhagic gastric varicose patients. Conclusion: Color Doppler sonography was very useful for the diagnosis of gastric and duodenal varices and for visualizing fine venous flows in the thickened gastric or duodenal wall. When it shows portal thrombosis in the confluence of the splenic vein and the superior mesenteric vein, duodenal varices should be suspected. The flow direction of the left gastric vein helps to differentiate hemorrhagic gastric varices from nonhemorrhagic ones.

Notes: Abstract. Background: The aim of this study was to reevaluate the causes and sites of intrahepatic venous collaterals and to determine the role of color Doppler sonography in the diagnosis of this relatively rare vascular abnormality. Methods: Real-time color Doppler sonography was used to study 21 patients with intrahepatic venous collaterals. The cause, distribution, and clinical manifestations of collaterals were determined, and Doppler waveforms obtained from the collaterals were also analyzed. Results: First, the causes of intrahepatic venous collaterals were divided roughly into two groups according to the presence or absence of veno-occlusions. The former group included liver tumors (six cases), primary Budd-Chiari syndrome (five cases), and metastatic adrenal tumors invading the inferior vena cava (two cases). The latter group consisted of diaphragmatic hernia (three cases), Osler-Weber-Rendu disease (two cases), and congestive liver (one case). The cause was not determined in two cases. Second, venous collaterals were distributed throughout the entire liver in primary Budd-Chiari syndrome but localized in the other cases. Third, Doppler waveforms of the collaterals were divided into two patterns: flat flow and multiphasic flow. Flat flow pattern was seen in patients with veno-occlusive diseases, and multiphasic flow pattern was seen in patients without veno-occlusive disease. Conclusion: The relationship between intrahepatic venous collaterals and veno-occlusive diseases has been emphasized in the literature, but the results of our series showed that they occurred under a wide variety of conditions, even without veno-occlusive diseases, including diaphragmatic hernia and Osler-Weber-Rendu disease. The analysis of the Doppler waveforms of the collaterals was useful in differentiating those due to veno-occlusive diseases and those not.

Notes: Abstract. Color Doppler sonograms and angiographic findings in 23 hepatic hemangioma patients were compared to clarify how arterioportal shunts influence color Doppler findings of hepatic hemangiomas. The results of our study showed that the presence of arterioportal shunts (six cases) gave rise to large feeding arteries (five cases), multiple intratumoral flows (six cases), and reversal of portal flow within (five cases) or around (four cases) the tumor. These color Doppler findings mimicked hypervascular malignant tumors. Knowledge of such unusual color Doppler findings in hepatic hemangiomas may help in avoiding misinterpretations of color Doppler sonograms. RID=""ID=""〈e5〉Correspondence to:〈/e5〉 H. Naganuma

Notes: Abstract Four cases of small abdominal aneurysms were assessed by color Doppler ultrasonography. The aneurysms demonstrated interesting and highly complicated internal hemodynamics, including a swirling blood flow pattern and/or a color mosaic pattern. These findings suggested the usefulness of color Doppler ultrasonography for obtaining details on internal hemodynamics, which cannot be obtained with other modalities, such as angiography or computed tomography (CT).

Notes: Abstract. Anomalous position of the gallbladder is relatively rare and has been reported only in isolated case reports. We tried to determine its ultrasound (US) findings on the basis of 18 such patients. In the left-side gallbladder group (nine patients), the gallbladder was imaged as an oval cystic mass in front of the pancreas. In all patients, the narrow neck of the gallbladder was clearly detected by US in the usual location before the main portal vein. Four of nine patients had small gallbladder stones. The retrohepatic gallbladder group (four patients) showed marked atrophy of the right lobe of the liver. Two patients had multiple gallstones in the bile ducts of the right lobe. All patients in the suprahepatic retrohepatic gallbladder group (four patients) were cirrhotic, and the anterior segment of the right lobe was markedly atrophied. In the intercostal scan, the gallbladder mimicked a perihepatic fluid. In the floating gallbladder group (one patient), the gallbladder was imaged as a cystic mass in the anterior abdominal wall. Surgical intervention showed a severely inflamed gallbladder, with small stones adhered into the anterior abdominal wall and partially ruptured. Knowledge of the wide range of US findings of malposition of the gallbladder helps in avoiding misdiagnosis.

Notes: Abstract The gastroepiploic vein (GEV) may serve as a collateral circulation associated with splenic vein thrombosis. Despite the extensive literature on its computed tomographic and angiographic findings, there is no description of color Doppler findings of the GEV. We report scanning techniques for observing its entire course. When examining patients with pancreatic disease, familiarity with these color Doppler findings could help in the detection of not only splenic vein thrombus but also the GEV and may contribute to patient management.

Notes: Abstract This study was undertaken to evaluate the role of color Doppler sonography in the preoperative assessment of vascular involvement in patients with pancreatic carcinoma. Twenty-six pancreatic carcinomas were investigated with color Doppler sonography and angiography, and the results of these examinations were compared with those of surgical findings. Color Doppler sonography was more sensitive than angiography in depicting vascular involvement of carcinoma. Thus, it seems rational to perform a preoperative assessment in suspected pancreatic carcinoma patients initially with color Doppler sonography to improve patient management.