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K Oho

Publications and source records attributed to K Oho.

90 records · Page 5Linked to original sources
PubMed1978

Study on the specificity of Shore's method for the determination of histamine in various tissues.

Specificity of Shore's method for the histamine determination was investigated by examining the fluorescence spectrum of the extract from rat gastric mucosa, biopsy specimen of human gastric mucosa, human gastric juice and human whole blood. An almost identical spectrum to that of pure histamine was obtained with the extract from rat gastric mucosa and human whole blood, whereas the spectrum with the extract of human gastric biopsy specimen and human gastric juice was different from that of histamine. By means of high-performance liquid chromatography, an approximately three times more concentrated extract from human gastric mucosa gave a distinct peak of histamine while a hundred times concentrated gastric juice gave no measurable peak of histamine. Fluorescence spectrum of the substances which might be extracted with histamine was examined. The ratio of the fluorescence of histidine to that of equimolar concentration of histamine at the wave length for histamine determination was 4.62%. From the above results, it has been concluded that Shore's method is useful for the determination of histamine contents in the gastric mucosa and whole blood if approximately 5% contamination with histidine is taken into consideration.

Animals↗
PubMedDate not supplied

Gastric mucosal blood flow after smoking in healthy human beings assessed by laser Doppler flowmetry.

We measured regional gastric mucosal blood flow by laser Doppler flowmetry before and after control (n = 8) or cigarette smoking (n = 8) in healthy human beings. The control group showed no change in both antrum (from 1.15 +/- 0.32 to 1.20 +/- 0.39 V, NS) and corpus gastric mucosal blood flow (from 1.15 +/- 0.32 to 1.12 +/- 0.28 V, NS). In contrast, cigarette smoking caused a significant reduction in gastric mucosal blood flow in the antrum (from 1.08 +/- 0.31 to 0.71 +/- 0.22 V, p < 0.01) and in the corpus (from 0.99 +/- 0.26 to 0.66 +/- 0.24 V, p < 0.01). The magnitude of reduction in gastric mucosal blood flow was similar between the antrum and the corpus (-34% +/- 11% versus -33% +/- 15%, NS). We conclude that cigarette smoking induces a significant reduction in gastric mucosal blood flow and that no heterogeneous response occurs in regional gastric mucosa. In addition, the laser Doppler flowmeter appears to be a sensitive method to assess rapid change in gastric mucosal blood flow in human beings.

Adult↗
PubMedDate not supplied

McCormack's endoscopic signs for diagnosing portal hypertension: comparison with gastroesophageal varices.

To assess the significance of McCormack's gastric mucosal signs for diagnosing portal hypertension, 100 controls and 100 patients with cirrhosis and portal hypertension underwent endoscopy. Each endoscopic recording was reviewed by multiple blinded observers to reduce bias. Individual signs more frequently observed in patients with cirrhosis and portal hypertension than in controls were fine pink speckling (20% versus 8%, p < 0.05), the snakeskin pattern (30% versus 5%, p < 0.01), and cherry-red spots (15% versus 3%, p < 0.01). In contrast, the prevalence of superficial reddening was similar in the two groups (7% versus 13%, NS). Overall, these gastric mucosal signs also appeared more commonly in patients with portal hypertension than in controls (54% versus 27%, p < 0.01); the sensitivity, specificity, and accuracy of McCormack's signs (overall assessment) for diagnosing portal hypertension were 54%, 73%, and 64%, respectively. Corresponding figures for modified McCormack's signs (exclusion of superficial reddening) were 50%, 85%, and 68%. However, these figures were still lower than those for gastroesophageal varices (72%, 100%, and 86%). We conclude that (1) superficial reddening is not a specific finding in patients with portal hypertension, and (2) gastric mucosal findings are of low sensitivity and specificity for diagnosing portal hypertension compared with gastroesophageal varices.

Esophageal and Gastric Varices↗
PubMedDate not supplied

Effects of vaso-active agents on hepatic function and blood gases in patients with cirrhosis: a study of vasopressin and nitroglycerin.

The effects of vaso-active agents on hepatic function and splanchnic oxygenation were studied in 17 patients with cirrhosis and portal hypertension. Eight patients received vasopressin (0.3 iu/min) and nine patients received nitroglycerin (50 micrograms/min). Both drugs caused a significant reduction in the portal venous pressure gradient. Vasopressin infusion significantly decreased intrinsic clearance of indocyanine green (-23%, P less than 0.01). This may be due to a decreased hepatic perfusion (-28%, P less than 0.01) and portal venous oxygenation (-15% in portal venous oxygen tension, P less than 0.05). In contrast, no changes in hepatic perfusion and portal venous oxygenation were observed after nitroglycerin infusion. Nitroglycerin did not decrease intrinsic clearance of indocyanine green. These results suggest that vasodilators, rather than vasoconstrictors, might be welcome in the treatment of patients with cirrhosis and portal hypertension.

Carbon Dioxide↗
PubMedDate not supplied

Lack of hepatic benefit by oxygen inhalation during vasopressin infusion in patients with cirrhosis.

Vasopressin has been found to impair hepatic function in patients with cirrhosis. The aim of this study was to investigate whether oxygen inhalation could improve hepatic function during vasopressin infusion. Vasopressin (0.3 iu/min) was infused into eight patients with cirrhosis for 50 min. During the first 30 min they were ventilated by room air and for the following 20 min by oxygen (approximate 50% of FiO2). The extra oxygen inhalation caused a typical increase in arterial (+7%, P less than 0.01), portal venous (+8%, P less than 0.05), and hepatic venous (+9%, P less than 0.01) oxygen content. No effect was noted in arterio-hepatic venous and portal venous-hepatic venous oxygen content difference in comparison with the values after vasopressin alone. The hepatic perfusion remained unchanged. These results suggest that the extra oxygen did not increase hepatic oxygen uptake. Similarly, intrinsic clearance of indocyanine green did not improve. It is concluded that oxygen supplement in this setting has no hepatic benefit in patients with cirrhosis.

Adult↗