Interleukin-1 enhances the ability of cultured human umbilical vein endothelial cells to oxidize linoleic acid

Human umbilical vein endothelial cells (HUVEC) were treated with recombinant interleukin (IL)-1 beta, and the metabolism of exogenous linoleic acid was studied. High performance liquid chromatography, gas chromatography-mass spectrometry, and chiral analysis revealed that HUVEC enzymatically convert linoleic acid mainly into 13-(S)hydroxy-9(Z),11(E)-octadecadienoic (13-HODE) and 9-(R)hydroxy-10(E),12(Z)-octadecadienoic acids, which may isomerize toward all-trans compounds. IL-1 beta increased the formation of all octadecanoids in a time- and dose-dependent manner with similar EC50 (approximately 1 unit/ml). The apparent Km values of linoleic acid were 15.59 +/- 8.39 and 152.9 +/- 84 microM (p < 0.05) in IL-1 beta-treated cells and controls, respectively, indicating a higher substrate affinity in cells stimulated with IL-1 beta. Ratios of S/R enantiomers for the hydroxyoctadecanoids produced by untreated and IL-1 beta-treated cells were similar to those from isolated cyclooxygenases (COXs), whereas isolated 15-lipoxygenase yielded 13-HODE with a strict S configuration. The formation of octadecanoids was inhibited in a dose-dependent manner by several COX inhibitors in both controls and IL-1 beta-treated cells, COX2 selective inhibitors being more effective on IL-1 beta-treated cells than on controls. COX1 and COX2 protein levels increased less than 2-fold and 8-fold, respectively, after IL-1 beta treatment. The specificity of COX inhibitors was proven since they did not inhibit 13-HODE formation by human polymorphonuclear leukocytes. Overall, these results indicate that COXs are responsible for the oxidative metabolism of linoleic acid in HUVEC, and IL-1 beta increases it by inducing the expression of new enzyme, mainly COX2.

Nicotinic acetylcholine receptors on the surface of the blood fluke Schistosoma

Blood dwelling stages of schistosomes have acetylcholinesterase (AChE) on their teguments. As an initial step towards understanding the function of tegumental AChE, we have used specific ligand-binding assays to identify nicotinic acetylcholine receptors (nAChR) on the schistosome surface. AChR could not be detected on migratory stages using fluoroscein isothiocyanate-alpha-bungarotoxin binding but the amount of specific labelling increased on sexual pairing and as the parasites matured into egg-producing adults. Both AChE and nAChR were concentrated on the dorsal surface of the adult male. These results indicate a role for AChE and AChR associated with the transporting function of this membrane.

[Pacemaker implantation in a patient with persistent left superior vena cava and atresia of the right superior vena cava]

Persistent left superior vena cava with absence or atresia of right superior vena cava is a congenital abnormality of systemic venous return to the heart which may complicate the insertion of a pacemaker electrode. We present a case report of a patient with conduction system disturbances in whom this abnormality was diagnosed during pacemaker implantation, with the possibility of using a transvenous electrode without active fixation system.

Effect of bovine respiratory syncytial virus infection on hypersensitivity to inhaled Micropolyspora faeni

Respiratory syncytial virus causes mild-to-severe respiratory disease in human infants and young children; a closely related bovine respiratory syncytial virus causes a similar disease pattern in calves. Increased disease severity in atopic children suggests that allergic reactivity may enhance the severity of RSV-induced disease. To examine the association between bovine respiratory syncytial virus (BRSV) infection and allergic reactivity two groups of calves were exposed to aerosolized Micropolyspora faeni (Mf) during an experimental BRSV infection. One group exposed to Mf concurrent with BRSV was challenge-exposed to Mf while infected a second time with BRSV, while the other similarly sensitized and infected group was mock challenged. A control group was exposed only to Mf aerosol and another control group was infected with virus but not exposed to Mf aerosol. Parameters examined included: clinical signs, Mf-specific IgG and IgE, BRSV-specific antibody and IgE, leukotrienes C4 and B4 prostaglandins E2, F2 alpha and D2, and lung pathology. While the initial BRSV infection failed to enhance sensitization to inhaled Mf, a second BRSV infection exacerbated clinical signs resulting from Mf aerosol. Consideration of eicosanoid and antibody profiles together with clinical signs suggests that mechanisms of both type I and type III hypersensitivity were operative during Mf challenge of sensitized calves.

The amount of acetylcholinesterase on the parasite surface reflects the differential sensitivity of schistosome species to metrifonate

Acetylcholinesterase (AChE) is present in all stages of the life-cycle of schistosomes and is located in muscle and on the surface of the parasite. Metrifonate is a drug that inhibits AChE. We compared the AChEs from three schistosome species (Schistosoma mansoni, Schistosoma haematobium and Schistosoma bovis) that have different susceptibilities to metrifonate in vivo. Sensitivities to AChE inhibitors were similar. The subunits of AChE were 110 kDa and 76 kDa and the dominant molecular form of AChE was a G2 form in all three species. This was the major form on the tegument while additional molecular forms were associated with the internal tissues. Differences in relative amounts of AChE activity between these species were found in the adults but not in the schistosomula. At the adult stage the major difference between species lay in the relative amounts of AChE activity in their teguments. S. haematobium teguments carried 20 times and S. bovis 6.9 times the activity present on S. mansoni teguments. These quantitative differences associate with the relative sensitivities of these species to metrifonate.

Massive intraoperative pulmonary embolism

Intraoperative massive pulmonary embolism is extremely rare. We describe such a case in a patient treated for a prolonged period preoperatively with intravenous heparin after an acute myocardial infarction and unsuccessful attempt at angioplasty, emphasizing that the problem should be borne in mind to facilitate expeditious and appropriate management. A clue to the diagnosis is interruption of venous return that is not due to a kink in the cannulae.

Corrosion cast studies of the bronchial arteries

The bronchial a. are the nutrient vessels of the lung. Despite being high pressure (systemic) vessels they are of very small size compared to the pulmonary a. and their side branches are normally so minute that they are extremely difficult to visualize during in vivo studies--yet these branches also supply many important mediastinal structures including the esophagus, trachea, lymph nodes, pericardium, aorta, and mediastinal parietal pleura. The bronchial a. can react vigorously to pathological changes in the lung by hypertrophy and increased flow and their precise anatomy has become of increasing importance with the development of interventional techniques involving the systemic circulation of the lungs. In order to demonstrate the distribution and extent of these vessels we have adopted a casting technique using injections of various colors of latex to distinguish between pulmonary a. and veins, bronchial a. and veins and their connections with the pulmonary vascular bed in both normal and diseased lungs.

Limited proteolysis of tumor cells increases their plasmin-binding ability

Mild proteolytic treatment of SW1116 tumor cells with trypsin or plasmin increases their plasmin-binding ability considerably by increasing the number of binding sites without altering their affinity. This mechanism may be operative for increasing the concentration of active plasmin at the surface of tumor cells. C-terminal lysine residues are involved in plasmin binding to cells, since treatment of cells with carboxypeptidase B decreases this binding by 50%.

Aging and renal clearance of procainamide and acetylprocainamide

Thirty-two patients had blood and urine collected simultaneously for measurement of procainamide, acetylprocainamide, and creatinine. The ratios of drug clearance to creatinine clearance were calculated for each. The procainamide:creatinine clearance ratio averaged 2.9 +/- 1.6 (SD) and fell as age of the patients rose (r = 0.5, p < 0.01). The acetylprocainamide:creatinine clearance ratio averaged 1.7 +/- 0.8 and also fell with age. The combination of decline in overall renal function with age with this decrease in the rate of renal tubular secretion of these drugs led to a progressive age-related rise in the steady-state serum level of procainamide (r = 0.56, p < 0.01) and acetylprocainamide (r = 0.36, p < 0.1) achieved by any dose of procainamide. Thus, the dosage of procainamide must be individualized for both overall renal function (GFR) and the age-related variations in renal tubular secretion that are of most note in children and the elderly.

[Renal pancreatic venous anastomosis: anatomical, clinical and radiological study]

Abnormalities in the left urinary tract have been observed secondary to pancreatopathies. Venous connections between the distal spenopancreatic venous bed and the left adrenal-renal venous system have been demonstrated by cast corrosion technique and by radiographic studies in the cadaver. In all of our anatomic studies, except on one occasion, numerous venous connections between the portal and systemic veins were demonstrated. The intravenous pyelogram and particularly nephrotomography have great value when pathology of the body and/or tail of the pancreas is suspected. Indirect sign on the left renal vein thrombosis on the left side may suggest the presence of a pancreatopathy. With acute and chronic pancreatitis, pseudocyst of the pancreas, and pancreatic carcinomas, we have noticed changes in the left urinary tract.

The deceptive aortic root

Coronal, horizontal, and sagittal sections through the mid-line are excellent ways of depicting the anatomical position of the aortic root and for studying its topographical relationship to the surrounding vascular structures. Minimal radiographic abnormalities or no abnormalities at all may be present with an enlarged ascending portion of the thoracic aorta. Thus, frontal chest roentgenograms obtained with high kilovoltage, fluoroscopy and left anterior oblique projections should be utilized routinely for the evaluation of the ascending aorta. Calcification of the aortic valve and of the coronary arteries and the study of aortic valve prosthesis also demand a dynamic study and the use of complementary views, such as lateral and both oblique projections.

Selective catheterization of the portal vein and its tributaries. Preliminary report

The portal vein and its tributaries were selectively catheterized in 90 patients. Only one complication required surgery. This technique not only provides information about the status of the portal circulation and liver parenchyma but can also be used in the treatment of bleeding esophageal varices by selective embolization of autologous clots or inert material.