3082. Protein-phospholipid interactions in pulmonary surfactant. The Parker B. Francis Lectureship.
SP-B is the protein in pulmonary surfactant with the greatest capacity to augment the phospholipids, ability to resist surface tension, and capability to prevent collapse of pulmonary alveoli. Synthetic peptides derived from the structure of SP-B and simplified analogues of these SP-B-derived peptides were found by tryptophan fluorescence to partition within the phospholipid layer in contact with both polar head groups and acyl side chains of the phospholipids. The intermittent hydrophilic basic residues were found to be essential for full activity, probably because of electrostatic interactions formed with phosphates of the polar head groups. The hydrophobic stretches of residues in SP-B and the related peptides supplement the activity through interaction with the phospholipid acyl side chains. By increasing intermolecular and intramolecular order of the phospholipid layer and thereby stability of the layer, the SP-B analogues provide strong surfactant activity. Simplified peptide analogues of SP-B, dispersed in DPPC and POPG, provide strong surfactant activity in vitro and in the lungs of premature infant rabbits, rhesus monkeys, and humans.
3088. An interleukin-6 secreting myxoma in a hypertrophic left ventricle.
We describe a patient who had both a left ventricular myxoma and left ventricular hypertrophy; the myxoma was subsequently excised and revealed to produce interleukin-6. The combination of left ventricular myxoma and ventricular hypertrophy is uncommon. Interleukin-6 secreted from the myxoma may be an important factor in the pathogenesis of ventricular hypertrophy in this patient.
3089. Factitious hemoptysis. Adding to the differential diagnosis.
We report a dramatic case of factitious hemoptysis in a 36-year-old black man who presented with hemoptysis and chest pain.
3090. Malignant thymoma. A complicated triad of SVC syndrome, cardiac tamponade, and DIC.
A patient presented with multisystem disease due to a very aggressive malignant thymoma. The case was complicated by the triad of cardiac tamponade, superior vena cava (SVC) syndrome, and disseminated intravascular coagulation (DIC). A review of the English literature reveals this to be a unique constellation of clinical symptoms and that DIC was heretofore unreported.
3092. Use of metallic stents in relapsing polychondritis.
Relapsing polychondritis is a rare multisystem disease. We describe the presentation and treatment of a patient with relapsing polychondritis and review the literature. This patient had involvement of the tracheobronchial tree requiring insertion of metallic stents.
3093. Prevention and regression of coronary atherosclerosis. Is it safe and efficacious therapy?
Atherosclerotic coronary heart disease (CHD) continues to be the dominant disease in Western society. A large body of evidence directly linking serum cholesterol levels and CHD risk has stimulated population treatment strategies designed to reduce cholesterol and CHD risk. Data indicating a relation between low cholesterol and non-CHD risk have, however, suggested that cholesterol reduction may not always be desirable. The primary goal of this evaluative review of the available evidence was to answer the following question: Is prevention/regression therapy for CHD safe and effective?
3099. Pleural effusion in multiple myeloma.
We report the first case of IgA-kappa multiple myeloma presenting as a myelomatous and eosinophilic pleural effusion with increased adenosine deaminase activity. In a review of the literature, 80 percent of myelomatous pleural effusions are due to IgA multiple myeloma.
3100. Staphylococcus aureus pericarditis in HIV-infected patients.
Serious infections caused by Staphylococcus aureus in HIV-infected patients have been reported. Contributing factors in the development of invasive S aureus infections include a high rate of skin and nasal colonization, frequent dermatologic disease, and the use of intravenous catheters. The authors report three cases of S aureus pericarditis in HIV-infected patients. While cases of viral, mycobacterial, and malignant pericardial effusions in HIV-infected patients have been reported, a review of the literature disclosed only three cases of bacterial pericarditis. Despite appropriate antibiotic therapy and drainage, a patient's condition may abruptly deteriorate and progress to tamponade. Early recognition of bacteremia and pericarditis and monitoring for cardiac tamponade, along with aggressive treatment, can result in a favorable outcome, but mortality remains high, particularly when S aureus is the causative agent.
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