The relation of temperature and lipid composition to cell adhesion.

We have examined as a function of temperature the effect of changes in the composition of the fatty acid chains of membrane phospholipids on the rate of cell to cell adhesion in the neuronal cell line B103. The rate of cell to cell adhesion in this cell line is highly temperature dependent but is not influenced by changes in the fatty acid composition of the plasma membrane generated by growing the cells either in the presence of oleic acid or elaidic acid. In contrast the temperature dependence of the rate of cell to cell adhesion, measured in a monolayer adhesion assay, is highly dependent on the shear force used during the assay. A two-step model of cell to cell adhesion involving multiple adhesion ligands is presented which can be used to explain these observations.

Determination of right ventricular pressure in the presence of a ventricular septal defect using continuous wave Doppler ultrasound.

Continuous wave Doppler ultrasound was employed in 38 patients with ventricular septal defects, many with associated lesions, to measure the velocity (V) of the shunted blood. Using the modified Bernoulli equation (delta P = 4V2) the pressure difference (delta P) between the ventricles was determined. In 22 patients both right ventricular and either left ventricular or ascending aortic pressure were measured at the time shunt velocity was determined. In another 16 patients these measurements were not obtained simultaneously but in most they were done within 24 hours of each other. In the entire group, measured pressure differences between the ventricles (or aorta and right ventricle) ranged from 0 to 97 mm Hg (mean 52 +/- 24). On the basis of velocity measurements the pressure difference ranged from 7 to 112 mm Hg (mean 51 +/- 24). A close correlation was found between the two methods (r = 0.95, SEE = 7.8 mm Hg). This accuracy was not altered by associated lesions. These findings indicate that by the use of continuous wave Doppler interrogation right ventricular pressure can be accurately measured in the presence of a ventricular septal defect.

Effect of hapten heterology on thyroid hormone immunoassays.

We examined the effects of hapten heterology on triiodothyronine (T3) and thyroxine (T4) immunoassays configured with protein-conjugated diiodothyronine (T2), T3 or T4, using acridinium ester (AE) as a chemiluminescent label and paramagnetic particles (PMP) as a solid phase. Assays constructed with hapten-heterologous combinations, such as immobilized anti-T4 plus labeled T3 or immunobolized anti-T3 plus labeled T2, were superior to the homologous ones in their potential for attaining higher sensitivity. This was manifested in a shift of the displacement curves to lower analyte concentrations, accompanied by unexpectedly high bound-tracer/total-tracer (B/T) ratios. This effect of hapten heterology was apparent with the use of either monoclonal or polyclonal antibodies and did not depend upon which component (antibody or protein conjugated hormone) was immobilized on the solid phase. In contrast, heterologous displacement curves with unconjugated hormone (125I-labeled) or with a labeled Fab fragment exhibited both a shift to lower analyte concentration and the expected decrease of B/T ratios. These results can be explained by the existence of positive binding cooperativity in the interaction between antibodies and haptenated proteins. Assay specificity was not adversely affected by hapten heterology when utilizing monoclonal antibodies, and hormone levels measured in serum samples correlated well with values obtained in homologous immunoassays.

Glycosaminoglycans of bovine aorta endothelial cells: identification and localization by use of a platelet factor 4-fluorescein probe.

We utilized platelet factor 4 (PF4) conjugated to fluorescein to stain the proteoglycans of permeabilized fixed bovine aorta endothelial cells in monolayer culture. Treatment of the monolayers with chondroitin ABC lyase and/or a preparation from Flavobacterium heparinum was used to remove chondroitin sulfate and/or heparan sulfate before staining, with resultant separate identification and partial localization of these glycosaminoglycans. When PF4-fluorescein was utilized with untreated control monolayers, fairly uniform reticular, perinuclear, and cell surface fluorescence was seen. After treatment with chondroitin ABC lyase, fluorescence was retained only on the cell surface. In contrast, treatment with the F. heparinum preparation resulted in the loss of all cell surface fluorescence. Use of both glycosaminoglycan lyases together resulted in loss of essentially all the fluorescence. The cell surface heparan sulfate observed by fluorescence after removal of cell surface chondroitin sulfate appeared to be unevenly distributed, with a heavier accumulation at one pole of each cell. This technique offers a specific method for identification and partial localization of cell surface heparan sulfate.

Right cervical aortic arch associated with a ventricular septal defect.

A patient with a right cervical aortic arch and ventricular septal defect is presented. This is the second reported case to have this rare combination of defects and the first to have survived corrective surgery. The x-ray film findings are discussed, and the similarity to the right posterior aortic arch is stressed.

Patent ductus arteriosus with hypoplastic lung.

A median sternotomy approach was used for closure of patent ductus arteriosus associated with a hypoplastic right lung. The anterior approach to the left ductus is indicated if left thoracotomy is contraindicated.

Impairment of bronchial mucociliary clearance in long-term survivors of heart/lung and double-lung transplantation. The Paris-Sud Lung Transplant Group.

The study objective was to investigate bronchial mucociliary clearance after heart/lung and double lung transplantation. Bronchial mucociliary clearance was measured using a noninvasive radioaerosol technique: 99mTc-labeled albumin was aerosolized using a spinning-top generator (mass median aerodynamic diameter, 7.5 mu; geometric standard deviation, 1.5 mu). Radioactivity counts were acquired during 60 min with a gamma camera. A region of interest was drawn over the right lung delineated by a 133Xe lung ventilation image. Bronchial mucociliary clearance was assessed as the percentage of decrease in radioactivity per hour calculated on time-activity curves fitted by a monoexponential model. To exclude patients with acute lung rejection, opportunistic lung infection, and obliterative bronchiolitis, all patients with transplants underwent pulmonary function tests and bronchoscopic examination before clearance measurement. Eight heart/lung and five double-lung nonsmoking transplant patients with normal lung histology were studied 19.3 +/- 4.0 mo after surgery and compared to nine normal nonsmokers. A similar proximal deposition of the aerosol was obtained in patients with transplants and normal subjects; skew values of distribution histograms of aerosol radioactivity counts were 2.1 +/- 0.2 and 1.8 +/- 0.1, respectively, and the ratios between central and peripheral 99mTc radioactivity counts were 2.4 +/- 0.1 and 2.3 +/- 0.2, respectively. No significant difference was observed in bronchial clearance values between patients with heart/lung and double-lung transplants (26.4 +/- 3.0 percent/h vs 35.9 +/- 3.5 percent/h). Conversely, bronchial clearance was significantly lower in transplant recipients (30.0 +/- 2.5 percent/h) than in normal controls (58.7 +/- 6.2 percent/h; p < 0.001). This decreased bronchial clearance can be expected to increase the risk of lung infection in long-term survivors of heart/lung and double-lung transplantation.

Congenital orbital varices causing extreme neonatal proptosis.

PURPOSE: To report a 6-week-old male with extreme proptosis caused by thrombosed orbital varices. METHODS: A 6-week-old male presented with advanced proptosis of his left eye. Computed tomography and magnetic resonance imaging studies of the orbits revealed a heterogeneous cystic mass that filled the entire left orbit. Extreme proptosis and corneal exposure prompted urgent surgical excision of the mass. Histopathologic review of the lesion was consistent with orbital varices. CONCLUSIONS: Although orbital varices usually are found in adults, they should be considered in the differential diagnosis of orbital lesions in children. Observation is usually warranted, but surgical intervention may be necessary in advanced cases.

Ocular hydrofluoric acid burns.

A 30-year-old man sustained exposure of his eyes, face, and neck involving 4% of body surface area to hydrofluoric acid. He was treated with immediate lavage and topical calcium gluconate. Because free fluoride ions from ocular and facial exposures can form complexes with body stores of calcium and magnesium, the patient was transferred to a burn unit for cardiac and electrolyte monitoring. He was also treated with calcium gluconate skin injections, pulmonary nebulizer therapy, and topical antibiotics and corticosteroids. In another case, a 25-year-old man with less severe exposure to hydrofluoric acid was treated as an outpatient with topical antibiotics, corticosteroids, and cycloplegia. If an ophthalmologist is the first to treat a patient with chemical exposure, the history of hydrofluoric acid exposure must be obtained, and the burn team and other medical specialists must be quickly consulted to avoid potentially fatal complications.

[Histopathology and prognosis of thymomas. Statistical analysis of 200 cases]. / Histopathologie et pronostic des thymomes. Analyse statistique de 200 cas.

200 cases of thymoma operated on at the surgical centre of Marie-Lannelongue between 1955 and 1982 were reviewed and analysed statistically; their histology was compared and their evolutionary potential. Based on their degree of differentiation of the epithelial tumour component and on the proportion of non tumour associated lymphocytes, 4 histological types were defined: 1) Spindle-or-oval-cell thymomas where tumour cells reminiscent of normal involutive thymic cells were of small size with a tendency to form clusters, whorls or a glandular appearance; 2) Lymphocyte-rich thymomas where normal epithelial cells, few in number, reproduce the appearance of normal thymic cells; 3) Differentiated epithelial thymomas, comprised of large epithelial cells with abundant cytoplasm and clearly demarcated and often less numerous lymphocytes; 4) Undifferentiated epithelial thymomas, characterised by a poverty of lymphocytes and anaplastic epithelial cells with a raised nuclear cytoplasmic ratio, nuclear irregularity and mitosis. Statistically, there was a significant correlation between the degree of differentiation of the tumor and prognosis. Spindle-or-oval cell thymomas (type 1) and lymphocyte-rich thymomas (type 2) have an 80% survival at 5 years and a 75% survival at 10 years. Well differentiated epithelial thymomas of type 3 have a 75% survival at 5 years and a 50% survival at 10 years, finally undifferentiated epithelial thymomas (type 4); the survival rate was nil at 5 years.(ABSTRACT TRUNCATED AT 250 WORDS)