Akihiko Kagami

Effects of gammalinolenic acid on plasma lipoproteins and apolipoproteins

Nineteen hypercholesterolemic patients (10 without and 9 with hypertriglyceridemia) were given evening primrose oil rich in gammalinolenic acid (GLA, 18: 3n - 6), in a placebo controlled cross-over design, over 16 weeks (8 + 8 weeks), with safflower oil as the placebo. During supplementation with evening primrose oil, dihomogammalinolenic acid (20: 3n - 6) increased in plasma lipids and red blood cells, and in subjects without hypertriglyceridemia there was a significant decrease in low density lipoprotein-cholesterol and plasma apolipoprotein B compared with the levels observed during safflower oil administration. Our results confirmed that evening primrose oil is effective in lowering low density lipoprotein in hypercholesterolemic patients.

Ischemia-reperfusion arrhythmias and lipids: Effect of human high- and low-density lipoproteins on reperfusion arrhythmias

SummaryThe effect of high- and low-density lipoproteins separated from human serum on the postischemic reperfusion arrhythmias was investigated. The hearts were perfused by working heart mode with Krebs Henseleit bicarbonate buffer containing arachidonic acid (1 μg/ml) for 5 minutes. Whole heart ischemia was induced by the use of a one-way ball valve, and hearts were perfused for 15 minutes followed by 20 minutes of reperfusion. Physiologic concentrations of high- and low-density lipoproteins were constantly infused through the atrial route during ischemic perfusion. Coronary effluent was collected via pulmonary artery cannulation for subsequent radioimmunoassay of thromboxane B2 and 6-keto-prostaglandin F1α, the major stable metabolites of thromboxane A2 and prostacyclin, respectively. The incidence of ventricular arrhythmias during reperfusion was 6/6 (100%), 1/6 (17%), and 6/6 (100%) in control, high-density lipoprotein and low-density lipoprotein infusion groups, respectively. There was no significant difference in coronary flow among the three groups throughout the perfusion. Both thromboxane B2 and 6-keto-prostaglandin F1α increased significantly during ischemia compared with preischemic values in all groups of hearts. However, the ratio of these two parameters varied in control and low-density lipoprotein infusion groups during ischemia, while there was no significant change in the high-density lipoprotein infusion group. These results provide the possibility that arachidonate metabolites may be involved in the regulation of ischemia-reperfusion arrhythmias and that high-density lipoprotein that was infused during ischemia markedly inhibits the incidence of ischemia-reperfusion-induced ventricular arrhythmias, due in part at least, to stabilizing the arachidonate metabolites during ischemic perfusion.

Effects of probucol and pravastatin on plasma lipids, activities of postheparin lipoprotein lipase, and lecithin cholesterol acyltransferase and apo A-I containing lipoproteins with and without apo A-II in patients with moderate hypercholesterolemia.

In this study, plasma HDL fractions were separated by ultracentrifugation and apo A-I containing lipoproteins (A-I Lp) were then isolated using anti-apo A-I immunoaffinity chromatography. The A-I Lp were further separated into two fractions with the use of anti-apo A-II immunoaffinity chromatography. One fraction, Lp A-I, contained apo A-I without apo A-II, while the other, Lp A-I/A-II, contained both apo A-I and apo A-II. These techniques were applied to investigate the changes in HDL apoprotein composition in hypercholesterolemic subjects treated with either probucol or pravastatin. Treatment with probucol (500 mg/day) or pravastatin (10 mg/day) reduced mean plasma total cholesterol concentrations by 24% (p < 0.01) and 16% (p < 0.05), respectively. Both drugs caused some reduction in lipoprotein lipase activity, but neither had any influence on the activity of hepatic triglyceride lipase or lecithin cholesterol acyltransferase. Their effects on HDL-cholesterol levels and apoprotein composition differed markedly. Probucol significantly decreased the HDL-cholesterol concentration, the plasma apo A-I/apo A-II ratio, and the number of large particles of diameter greater than 10.4 nm. When the ratios of Lp A-I and Lp A-I/A-II for the probucol-treated subjects were compared with those in the normolipidemic controls, and with the ratios before and after administration of probucol, a remarkable decrease in the level of Lp A-I was apparent. It is presumed that the decrease in HLD-cholesterol by prolonged probucol administration reflects the decrease of Lp A-I more than the decrease of Lp A-I/A-II.(ABSTRACT TRUNCATED AT 250 WORDS)

An autopsy case of pseudosarcoma of the common bile duct

An autopsy case of pseudosarcoma in the common bile duct is reported. An 82-year-old Japanese male complaining of jaundice was admitted to our hospital; he was examined by abdominal ultrasonography (US), revealing biliary calculus, dilatation of the common bile duct, and choledocholithiasis, considered to be the possible cause of the obstructive jaundice.Endoscopic retrograde biliary drainage (ERBD) and cholangioscopy were performed concurrently, revealing a vaguely whitish tumor near the papilla of Vater. Two months later, the patient died from complications of the liver, infection, and disseminated intravascular coagulation (DIC). An autopsy study revealed tumor cells with extreme pleomorphic changes, growing diffusely, very like sarcoma. Further examination revealed epithelioid arrangements in the metastatic lymph node. Twelve kinds of immunohistochemical examination showed a positive reaction, reflecting the presence of an epithelioid cytoskeleton. Of 28 cases of true and pseudosarcoma of the biliary system reported in the Japanese literature, only 1 case was reported, in 1990, to involve the common bile duct. We therefore report the present case of pseudosarcoma of the common bile duct.

Endoscopic Detection Rate of Minute Neoplasms in Autopsied Colons

Abstract: This study was designed to determine the actual incidence, distribution and morphology of minute neoplastic polyps, under 5 mm in diameter, in the so‐called normal colon obtained at autopsy. In order to increase the sensitivity of detection of minute lesions, this study was done with the aid of electronic endoscopy using the dye spraying method. The case‐occurrence of minute neoplastic polyps among the 49 autopsy cases was almost 50% and the ratio of cases without adenomas or cancers of the colon was no more than 50%. The ratio of minute neoplastic polyps among the total number of neoplastic polyps, based on electronic endoscopy, was much higher than that of minute polyps of autopsy cases reported previously with macroscopic observation. Regarding the grade of atypia of the minute neoplastic polyps, only one polyp (5 mm in diameter) among 85 lesions was a carcinoma. The results of this study indicate the possibility of considerable numbers of minute neoplastic polyps which are likely to go undetected by endoscopy, probably due to technical difficulties in endoscopic control and the lack of sufficient examination time for each patient.

Adhesive Effect of Ecabet Sodium in a Porcine Gastric Leer Model

Abstract: Protection of the gastric mucosa, based on its high affinity for mucosal lesions, has been reported as one of the antiulcer effects of ecabet sodium. We investigated the adhesive effect of this drug on mucosal lesions in a porcine gastric ulcer model (freshly isolated stomach) and on human mucosal lesions resulting from endoscopic gastric mucosal resection (EMR) and polypectomy. After ulcer lesions had been induced by EMR in the isolated porcine stomach, ecabet sodium and sucralfate suspensions were applied. After washing with citrate buffer, at a pH of 1, 3 or 5, the adhesion of each drug to the gastric mucosa was measured. At pH 1, both drugs showed satisfactory adhesion to the ulcer lesions. When the acidity of the ulcer surfaces was decreased to pH 3 and then to pH 5, the adhesion of sucralfate showed a marked decrease (100%→31→% 13%). while that of ecabet sodium showed only a slight decrease (100%→75%→64%). Futhermore, the activity of thrombin in the ecabet sodium suspension remained high at pH 1, 3 and 5. Since the ecabet sodium suspension produced a satisfactory covering effect on gastric mucosal lesions and this effect was maintained even at low acidity, this drug is considered suitable for endoscopic directsprinkling therapy for gastric mucosal lesions.

A Case of Terminal Ileum Lipoma Treated by Endoscopic Polypectomy

Abstract: This study reports on the case of a 71‐year‐old man who complained of repeated episodes of right lower abdominal pain. A barium enema and colonoscopy revealed a 20 times 20 times 15 mm smooth‐surfaced polypoid tumor (Yamada type III) located in the terminal ileum.