Malignant schwannoma of the heart

Primary cardiac tumor is an extremely rare disease entity. Only three cases of primary malignant cardiac schwannoma, the subject of this report, have been recorded in Japan. Recently, we encountered a case of malignant schwannoma in which retention of pericardial effusion was the first clinical finding. This case was a 30-year-old female, who had dyspnea at work, general fatigue, and fever. Striking cardiac expansion was seen, with a cardiothoracic ratio (CTR) of 69% on chest x-ray. Two-dimensional echocardiograms showed a large volume of pericardial effusion between the side wall of the left ventricle and the epicardium, and the presence of a parenchymatous tumor. An increase in tumor size was detected on chest computer tomography (CT) scan. Using a pump oxygenator, median sternotomy was performed to reach the epicardium. A pale yellow, soft tumor was seen in the left atrium near the left ventricle. Histologically, the patient was diagnosed as having a malignant schwannoma. We have reported a case of primary malignant schwannoma which was surmised to have arisen from the boundary between the atrium and the ventricle.

5-lipoxygenase inhibitor (AA-861) attenuates neutrophil-mediated oxidative stress on the venular endothelium in endotoxemia

Neutrophil-mediated oxidative stress on the rat mesenteric microcirculation was studied in the experimental model of endotoxin-induced disseminated intravascular coagulation (DIC) by using an intravital fluorescent microscope equipped with a Silicon Intensifier Target Image Tube camera and luminol-dependent chemiluminescence (ChL) analysis. Leukocytes adhering to the venules were visualized by the injection of acridine orange, a fluorochrome tracer which shows high affinity to white cells. Endotoxin (E. coli, O-111 B4) was administered intravenously at a dose of 2 mg/kg/hour. After starting the infusion of endotoxin, the number of adherent cells gradually increased in the venular endothelium and was followed by a transient neutropenia. ChL activities from neutrophils were also significantly elevated, which may reflect the enhanced ability to generate oxygen-radicals. To elucidate the role of 5-lipoxygenase products in the locomotive and metabolic changes of neutrophils, the effects of AA-861, a specific inhibitor of 5-lipoxygenase was tested. In addition prednisolone and indomethacin were evaluated. AA-861 and prednisolone reduced neutropenia, leukocyte adhesion to the venular walls and ChL activities from neutrophils. It was concluded that 5-lipoxygenase may modulate neutrophil-mediated oxidative stress on microvasculature in endotoxin-induced DIC.

[The evaluation of cardiac function and the effect of therapy in acute myocardial infarction--comparison by radio nuclide method in acute and chronic phase]

The cardiac function and the effect of therapy in patients with acute myocardial infarction (AMI) were assessed in over 100 patients by analysis of 201Tl-scintigraphy and 99mTc-gated pool study in our ICU. The cardiac function and 201Tl-defect ratio were compared with the results obtained in chronic phase. Sixteen of them were treated with intravenous urokinase (UK) within 6 hours from onset. The other 18 patients without UK treatment served as a control group. Significant correlation was recognized between 201Tl-defect ratio and peak-CPK levels, peak-GOT levels, peak-LDH levels. Significant correlation (r = -0.655, r = -0.713) were found between 201Tl-defect ratio and LVEF in acute and chronic phase. The UK group showed a significant increase of LVEF as compared with the control group in patients with antero-septal (A/S) AMI. In inferior (INF) AMI, no significant differences were observed UK and control group in LVEF, RVEF and 201Tl-defect ratio. In chronic phase, improvements of LVEF and 201Tl-defect ratio were observed in patients with A/S AMI. But no significant differences of LVEF, RVEF and 201Tl-defect ratio were observed in A/S AMI in acute and chronic phase. The UK group showed a significant increase of LVEF (50.1%) as compared with the control group of A/S AMI in chronic phase. We have demonstrated that a combination of 201Tl-scintigraphy and 99mTc-gated pool study are useful techniques in ICU, to evaluate the cardiac function and the effect of thrombolysis therapy and thus greatly contribute to the primary care of AMI cases.

Systemic and coronary hemodynamic effects of beta-adrenoceptor blocking agents in coronary artery disease

Systemic and coronary hemodynamic effects of acebutolol (10 mg i.v.), a cardioselective beta-adrenoceptor blocking agent were investigated in 11 patients with coronary artery disease and significant arterial obstructive lesions. Efficacy was assessed by simultaneous left and right heart catheterization and with an inlaying Webster thermodilution catheter in the coronary sinus. The data were compared with data from 7 other patients who received 2 mg i.v. of propranolol, a non-cardioselective beta-blocker. With acebutolol, (1) the heart rate was reduced significantly (p less than 0.001), (2) no significant changes were observed in the LVSP, LVEDP, mean PWP, LVmax dp/dt/p, LV negative dp/dt/p, CI, SWI and SPI, (3) CSF and MVO2 decreased significantly (p less than 0.01) 5 min after injection and (4) the CVR showed a significant elevation (p less than 0.05) after 5 min. With propranolol, (1) the heart rate decreased significantly (p less than 0.05), (2) there were no significant changes in LVSP and LVEDP, (3) the mean PWP increased significantly (p less than 0.05), (4) the LVmax dp/dt/p, CI and SWI decreased significantly (p less than 0.05), (5) the CSF and MVO2 decreased markedly (p less than 0.01) and (6) the CVR increased markedly (p less than 0.01). As compared to the effects of 2 mg i.v. of propranolol, those produced by acebutolol (10 mg i.v.) were characterized by a predominant negative chronotropic action with minimal negative inotropic action, combined with a reduction in CSF and MVO2. The findings suggest that the efficacy of acebutolol in pump failure caused by myocardial ischemia during effort angina is mediated by improvement of the myocardial oxygen demand-supply imbalance.

Reflectance spectrophotometry for the assessment of gastroduodenal mucosal perfusion

Reflectance spectrophotometry in assessing gastroduodenal mucosal perfusion was evaluated. Ischemia without congestion, e.g., during hemorrhagic hypotension or celiac artery occlusion, was associated with a reduction in the indexes of mucosal hemoglobin concentration and of oxygen saturation. Ischemia with congestion, e.g., during portal vein occlusion, or in absolute ethanol or suction-induced mucosal lesions, was associated with an increase in the index of mucosal hemoglobin concentration but a reduction in the index of oxygen saturation. An increase in the index of mucosal hemoglobin concentration associated with a normal index of oxygen saturation was found in the postischemic hyperemia after release of celiac artery occlusion and during the sustained increase in corpus mucosal blood flow induced by vagus nerve stimulation. Thus reflectance spectrophotometric measurements reflected ischemia, without or with congestion, and hyperemia. Additionally, although regional differences in reflectance spectrophotometric measurements were demonstrated in the duodenal, antral, and corpus mucosa, such differences bore no consistent relationship to regional differences in blood flow demonstrated in previous studies.

Effect of exogenous acid on the rat gastric mucosal microcirculation in hemorrhagic shock

In vivo microscopy and histology were used to study the effect of exogenous acid (0.1 N HCl) on the rat corpus mucosal microcirculation and bleeding in hemorrhagic shock. Systemic blood pressure was reduced stepwise by bleeding. Mucosal blood flow showed a significant linear correlation with mean systemic blood pressure. The flow stopped in half of the rats at 25% of control blood pressure, but red blood cells were always present within the microvessels. In contrast, the topical application of 0.1 N HCl accelerated the decrease of blood flow with graded hypotension and caused progressive disappearance of the honeycomblike network of red blood cell-filled superficial mucosal microvessels. After retransfusion, mucosal bleeding occurred in the area in which the blood-filled microvessels had disappeared. Histology revealed that the bleeding extended from the middle of the depth of the mucosa and was associated with tissue necrosis. These results indicate that exogenous acid in hemorrhagic shock causes increased mucosal ischemia and tissue damage with bleeding on retransfusion.

Inhibitory effect of somatostatin on cholera toxin-induced diarrhea and glycoenzyme secretion in rat intestine

The effects of somatostatin on cholera toxin-induced secretory diarrhea and the appearance of glycoenzymes in the intestinal lumen and intestinal lymph were investigated in rat small intestine. After exposure to cholera toxin, marked fluid accumulation in the small intestinal tract and elevation of the jejunal mucosal cyclic AMP (cAMP) concentration were observed. The activity of alkaline phosphatase, aminopeptidase and sucrase increased in the intestinal lumen after toxin exposure. In intestinal lymph, alkaline phosphatase activity was increased after cholera toxin administration, while aminopeptidase activity remained unchanged. Somatostatin suppressed cholera toxin-induced secretory diarrhea, but it did not affect the elevated mucosal cAMP concentration. This peptide also inhibited the appearance of glycoenzymes in the intestinal lumen and lymph induced by cholera toxin administration. These results suggest that somatostatin exerts its inhibitory effects on cholera toxin-induced secretory diarrhea and on the appearance of glycoenzymes in the intestinal lumen and lymph by affecting processes beyond cAMP formation.

Microvascular actions of platelet-activating factor on rat gastric mucosa and submucosa

Intravenous infusion of platelet-activating factor (PAF or AGEPC) induces extensive acute hemorrhagic damage in the ra gastric mucosa. The effects of PAF have now been investigated on several microcirculatory parameters in the rat gastric mucosa. Infusion of PAF (25-100 ng X kg-1 X min-1 iv) dose-dependently reduced systemic arterial blood pressure and mucosal blood flow, as determined by hydrogen gas clearance. Microscopic observation likewise indicated a dose-dependent slowing of mucosal capillary blood flow, as determined by red blood cell velocity after PAF infusion with stasis of flow at the highest dose. These actions were not the consequence of vasoconstriction, since there was no significant change in arteriolar and venular vessel diameter in the submucosa during PAF infusion, although a dose-related slowing and stasis of blood flow was observed. There was no capillary leakage of plasma protein in the gastric mucosa during PAF infusion, as determined by a fluorescence marker (FITC-BSA) technique. The precursor and breakdown product, lyso-PAF (200 ng X kg-1 X min-1) had no significant action on any of these microcirculatory parameters. These observations support the suggestion that microvascular changes leading to stasis may contribute to the ulcerogenic actions of PAF.

Clinical evaluation of plasma abnormal prothrombin (PIVKA-II) in patients with hepatocellular carcinoma

The clinical usefulness of plasma abnormal prothrombin, defined as a protein induced by vitamin K absence or antagonist-II: PIVKA-II, as a tumor marker for hepatocellular carcinoma (HCC), was evaluated. Plasma PIVKA-II concentration was determined by an enzyme-linked immunosorbent assay (ELISA) using a monoclonal antibody specific for PIVKA-II. Forty-one (65%) out of 63 patients with HCC had an abnormal PIVKA-II level above 0.13 arbitrary units (AU)/ml; the level was above 0.3 AU/ml in 33 patients (52%) and above 0.5 AU/ml in 27 patients (43%). On the other hand, most of the 282 patients with various liver diseases other than HCC had normal or slightly elevated levels of PIVKA-II. Their values were all below 0.5 AU/ml, with the exception of 2 patients with decompensated liver cirrhosis. The patients with PIVKA-II values above 0.5 AU/ml were strongly suspected of having HCC. Plasma PIVKA-II levels were not related to serum alpha-fetoprotein (AFP) levels, but were above 0.5 AU/ml in 14 (44%) out of the 32 patients whose serum AFP levels were below 400 ng/ml. In some patients with HCC, PIVKA-II was increased throughout the course of the disease, and in others it normalized after surgical resection of the tumor. We conclude that the plasma PIVKA-II assay by the ELISA method using a monoclonal antibody is a useful diagnostic tool for monitoring HCC, particularly in HCC patients with low AFP levels.

[Evaluation of the visualized left atrium by 201Tl myocardial scintigraphy]

201Tl myocardial scintigraphy was evaluated in patients with 18 mitral stenosis cases. Left atrium was to be seen in ANT (16.7%), LAO (16.7%), MLAO (16.7%) and L-LAT (11.1%), respectively. Furthermore, 201Tl uptake ratio of left atrium, right ventricle, pulmonary area tended significantly to increase in visible group compared with invisible group. PCW pressure was correlated with left atrial Tl uptake (r = 0.51, p less than 0.005), and it indicated some correlation between left atrial pressure and 201Tl uptake.

Interaction of rat ascites hepatoma cells with cultured mesothelial cell layers: a model for tumor invasion

Interactions of rat ascites hepatoma cells with primary cultured layers of rat mesentery-derived cells were studied. The mesentery-derived cells were isolated from rat mesentery and cultured in Eagle's minimum essential medium with a 2-fold concentration of amino acids and vitamins supplemented with 10% calf serum. The primary cultured cells, consisting mainly of mesothelial cells in polygonal shape, forms a "paving stone" sheet. Upon seeding the tumor cells on the mesentery-derived cell layers, three different types of tumor cell growth were observed. Type 1 was the formation of piled-up tumor cell nests on mesothelial cell layers. Type 2 was the formation of flattened tumor cell islands underneath mesothelial cell layers. This island formation was clearly observed under a phase contrast microscope 2 days after the tumor cell seeding. Protrusion of cellular processes of the tumor cells beneath mesothelial cells was occasionally seen. Type 3 was the growth of tumor cells in suspension. These types of tumor cell growth closely resemble those in the peritoneal cavity observed after i.p. implantation of the tumor cells. When the tumor cells recovered from the blood of tumor-bearing rats were seeded, flattened tumor cell islands were formed 15 times more frequently than when the tumor cells isolated from host peritoneal cavity were seeded. Shortly after the appearance of small flattened tumor cell islands, a distinct morphological change of mesothelial cells from polygonal to spindle shape was seen preferentially at the marginal area of the cell layers (a partial retraction of cell edges). The retraction of mesothelial cells was induced not only by seeding the tumor cells but by adding the tumor ascites fluid or the medium conditioned by the tumor cell culture. The morphological change was reversed by changing the culture medium to remove the effectors. These results indicate that the system described in this study can provide a useful model to study tumor cell invasion.

Vagal nerve stimulation causes noncholinergic dilatation of gastric arterioles

Vagal nerve stimulation causes prompt dilatation of gastric submucosal arterioles (the vessels that control gastric mucosal blood flow) in rats. In vivo microscopy was used to determine whether this direct vasodilator effect of vagal nerve stimulation on rat gastric submucosal arterioles is mediated by cholinergic fibers. Acetylcholine and atropine were topically applied to the submucosa. The distal end of the severed vagus nerve was electrically stimulated (8 V, 2 ms, 6 Hz, 20 s) subdiaphragmatically. Diameter changes of the submucosal arterioles were videotaped and measured with an image-splitting technique on playback of the videotapes. Acetylcholine, 10(-7) to 10(-5) M, dilated the arterioles dose dependently. Atropine prevented the acetylcholine-induced dilatation, 10(-5) M, nearly completely inhibiting the dilatation. Vagal nerve stimulation dilated the arterioles promptly, and this dilatation was not blocked by 10(-5) M atropine, a dose that blocked the acetylcholine-induced dilatation. These results indicate that vagal nerve stimulation causes atropine-resistant, noncholinergic dilatation of gastric submucosal arterioles in rats.

Malabsorption of long-chain fatty acid in cholera toxin-induced secretory diarrhea

The effects of cholera toxin-induced diarrhea on the absorption of fatty acids of different chain lengths were investigated using rat small intestine. In the study using isolated jejunal loops, the absorption of the long-chain fatty acid, linoleic acid, into the intestinal mucosa was significantly impaired 90 min after the administration of linoleic acid micelles in the cholera toxin-treated rats. This reduction of linoleic acid absorption in the cholera toxin-treated rats was not found at 180 min. We could not find any mucosal accumulation of labeled linoleic acid or disturbance of triglyceride formation in the intestinal mucosa as compared with that of controls. The amount of linoleic acid transported into the intestinal lymph was delayed and reduced in cholera toxin-treated rats. Furthermore, the absorption of the medium-chain-length fatty acid, octanoic acid, was unchanged in the cholera toxin-treated rats. These results suggest that intestinal secretion induced by cholera toxin may delay the mucosal uptake and lymphatic transport of long-chain fatty acids. Cholera toxin may not affect triglyceride formation in the epithelial cells.

[Effect of hemodialysis on left and right ventricular function--evaluation using electrocardiogram gated radionuclide ventriculography]

Eighteen outpatients with chronic renal failure undergoing hemodialysis (HD) were studied. Immediately before and after HD, the left and right ventricular function measured by electrocardiogram gated radionuclide ventriculography (RNV). By HD, body weight changed 58.6 +/- 7.50 kg to 57.2 +/- 6.80 kg and BUN level changed 67.9 +/- 29.00 mg/dl to 37.1 +/- 18.96 mg/dl and creatinine level changed 11.3 +/- 3.90 mg/dl to 6.8 +/- 2.48 mg/dl. Before HD, cardiac output was 8.08 +/- 1.50 l/min and cardiac index was 5.00 +/- 0.87 l/(min m2). Left ventricular function improved (LVEF changed 60.4 +/- 6.85% to 64.2 +/- 8.7%, LVEF/LVET changed 0.237 +/- 0.048%/ms to 0.254 +/- 0.021%/ms) between before and after HD, but there was not significant difference. Right ventricular function improved (RVEF changed 41.2 +/- 8.00% to 50.0 +/- 11.96, RVEF/RVET changed 0.167 +/- 0.028%/ms to 0.209 +/- 0.059%/ms) between before and after HD, and there was significant difference (p less than 0.05).