Clinical features and natural history of central cavitary necrosis.

Central cavitary necrosis (CCN) is an unusual complication of acute pancreatitis in which the necrosis is confined almost entirely to the pancreatic parenchyma and there is little if any extrapancreatic necrosis. In our experience with 10 patients with CCN, clinical features suggested that the episodes of acute pancreatitis were initially severe, with high Ranson scores (mean, 4.2; range, 1-6), development of systemic complications, computed tomography (CT) grade of D or E by the Balthazar-Ranson scoring system, need for intensive care unit admission in 8 of 10 patients, and mean length of hospitalization of 56 days (range, 28-153 days).

Prevention of smooth muscle cell outgrowth from human atherosclerotic plaque by a recombinant cytotoxin specific for the epidermal growth factor receptor.

Smooth muscle cell proliferation in the intima of arteries is a principal event associated with vascular narrowing after balloon angioplasty and bypass surgery. Techniques for limiting smooth muscle cell proliferation, however, have not as yet yielded any therapeutic benefit for these conditions. This may reflect the present lack of sufficiently potent and specific inhibitors of smooth muscle cell proliferation.

Acute respiratory failure neuropathy: a variant of critical illness polyneuropathy.

Objective: To describe a severe axonal polyneuropathy that follows acute respiratory failure and, in turn, causes continued ventilator dependence and paralysis after resolution of the primary illness.

Design: Retrospective chart review of three patients and prospective analysis of two patients.

Setting: Respiratory and neurologic ICUs of a general hospital.

Neurobiology of schizophrenia.

Schizophrenia is the most prevalent of the major psychoses, but the underlying neurobiology of this debilitating disorder remains mysterious. Recent developments in molecular biology, neuroanatomic pathology, neurochemistry, and functional imaging suggest that a number of factors converge to produce schizophrenia. Specifically, an early neurodevelopmental "lesion," possibly within the mesial temporal lobe, may contribute to later temporolimbic-prefrontal dysfunction as the nervous system matures.

The role of inositol phospholipids in the association of band 4.1 with the human erythrocyte membrane.

Band 4.1 is a major protein of the erythrocyte membrane skeleton. It promotes the binding of spectrin to F-actin and may anchor the skeletal network to the plasma membrane via its association with integral membrane proteins.

Dependence of the permanent deformation of red blood cell membranes on spectrin dimer-tetramer equilibrium: implication for permanent membrane deformation of irreversibly sickled cells.

Red blood cells (RBCs) in sickle cell anemia, transformed into a sickled shape by prolonged deoxygenation, or normal RBCs deformed by a prolonged micropipette aspiration become permanently stabilized in their abnormal shape. This semisolid plastic behavior is thought to involve an irreversible reorganization of the membrane skeleton, but the exact nature of this skeletal rearrangement is not known. In this study, we first asked whether the irreversible deformation is associated with a permanent stretching of the skeletal network, and then whether it is due to a rearrangement of skeletal components involving a disruption of pre-existing protein associations and the subsequent reassociation of new protein contacts.

Direct myocardial transfection in two animal models. Evaluation of parameters affecting gene expression and percutaneous gene delivery.

Background: Gene therapy represents a novel approach to the treatment of a variety of disease states. Direct injection of pure untreated DNA into skeletal and cardiac muscle is sufficient to perform gene transfer in vivo. Little information is available, however, regarding the extent to which individual parameters of direct gene delivery affect the efficiency of myocardial transfection.

Successful management of paraprotein-associated peripheral polyneuropathies by immunoadsorption of plasma with staphylococcal protein A.

Two patients with paraprotein-associated peripheral polyneuropathy were treated successfully using immunoadsorption of patient's plasma with staphylococcal protein A. Both had previously been treated with immunosuppressive agents or plasma exchange, and were rapidly relapsing at the time of their protein A immunoadsorption therapy. One patient was treated "on-line" with a blood cell separator, and one was treated "off-line.

Effects of genotype on age-related alterations in the concentrations of stress hormones in plasma and hypothalamic monoamines in rats.

The adaptive response of the neuroendocrine system to stress is known to be impaired during ageing, and this impairment may be genetically determined. To elucidate further the effect of genotype, inbred male rats of the Wistar-Kyoto (WKY) strain, characterized by their hyper-reactivity to stressors and shorter life span, were compared with Brown-Norway (BN) rats. In young BN rats, resting prolactin concentrations were lower than in WKY animals and were reduced with age, while in WKY rats they remained unchanged with age.

How does angioplasty work? Serial analysis of human iliac arteries using intravascular ultrasound.

Background: Previous studies regarding the mechanism by which balloon angioplasty increases luminal patency have generally used animal models or postmortem specimens from occasional fatal cases of angioplasty performed in human patients. In either case, conclusions regarding participatory mechanisms have relied exclusively on nonserial, postangioplasty histopathological examination.

Methods And Results: In the present study, intravascular ultrasound examination was performed before and after balloon angioplasty in 40 consecutive patients with iliac artery stenoses.

Hidden colonic adenomas in a patient with a family history of polyposis.

We describe an asymptomatic patient with a strong family history of polyposis who was found to have flat and depressed adenomas that were not visible on colonoscopy. The diagnosis required assessment of multiple, randomly obtained biopsy specimens. Partial deflation of the colon during colonoscopy may allow hidden lesions to be seen.

The detection of occult renal tumors in children by elevated hematocrit on routine complete blood count: a report of two cases.

Wilms' tumor is a renal neoplasm usually found in young children and is rarely seen in teenagers. The production of erythropoietin by these tumors may result in secondary erythrocytosis, which should be reflected in complete blood counts (CBC). A search of the literature for reports of occult Wilms' tumors initially suspected on the basis of erythrocytosis was unrewarding.

Smooth muscle cell outgrowth from human atherosclerotic plaque: implications for the assessment of lesion biology.

Objectives: The purpose of this study was to determine whether the kinetics of smooth muscle cell outgrowth from in vitro explants of human atherosclerotic tissue is dependent on the nature of the atherosclerotic lesion in vivo.

Background: The use of techniques for percutaneous in vivo extraction of atherosclerotic plaque has provided the opportunity to study human atheroma-derived smooth muscle cells in culture. However, because of cell selection and changes in phenotype, in vitro findings may not always reflect the biologic properties of the vessel wall, particularly if cells are in culture for prolonged periods.

Platelet-derived growth factor activates membrane-associated phosphatidylinositol 3-kinase and mediates its translocation from the cytosol. Detection of enzyme activity in detergent-solubilized cell extracts.

Phosphatidylinositol 3-kinase (PI 3-kinase) activity has been detected in immune complexes with active protein tyrosine kinases, and its products have been measured in intact cells in response to growth stimuli. Both methods do not directly evaluate whole cell PI 3-kinase enzymatic activity. We have developed a sensitive method to measure PI 3-kinase activity in diluted, detergent-containing whole cell extracts and used this method to determine total, soluble, and membrane-associated PI 3-kinase activity in PDGF-stimulated NIH 3T3 fibroblasts.

Metastatic breast carcinoma presenting as persistent diarrhea.

Patients with breast carcinoma metastatic to the colon generally present with multiple symptoms, usually pain, vomiting, nausea, and ascites. We describe a patient who presented only with persistent diarrhea, underwent surgery for colon cancer, and, on pathological evaluation of the surgical specimen, was found to have metastatic breast cancer affecting the colon. Metastatic breast cancer should therefore be suspected in patients with a history of breast cancer and diarrhea of unknown cause that is not accompanied by other symptoms.

Prognostic factors in sterile pancreatic necrosis.

Although the overall mortality in sterile pancreatic necrosis is low, patients who experience systemic complications may have a higher mortality. To study the impact of systemic complications and other factors on survival, possible prognostic factors were evaluated among 26 patients who experienced at least one systemic complication. Mortality was 38%.

Neurological intensive care.

Neurological intensive care has evolved from the principles of respiratory care established during the poliomyelitis epidemics into a broad field encompassing all of the acute and serious aspects of neurological disease. The economic and political complexities of modern intensive care play a major role in organizing a unit and building a program. Central themes of practice in modern neurological intensive care units include the clinical physiology of intracranial pressure, cerebral blood flow, and brain electrical activity; the systemic abnormalities and medical complications of nervous system diseases; postoperative care; and management of neuromuscular respiratory failure.

Noninvasive carotid duplex ultrasound imaging for the evaluation and management of carotid atherosclerotic disease.

Renewed interest in surgical management of atherosclerotic disease of the carotid bifurcation underscores the necessity for accurate and efficacious means for diagnostic evaluation of patients with suspected carotid disease. Noninvasive testing by carotid duplex ultrasound, which combines high-resolution B-mode imaging with pulsed Doppler spectral analysis, is the method of choice. Noninvasive testing permits identification of potentially significant carotid stenosis, occlusion, or unstable plaque morphology with virtually no significant morbidity from the testing itself.

The role of closed pleural needle biopsy in the diagnosis of malignant mesothelioma of the pleura.

Malignant mesothelioma of the pleura is a disease that requires a biopsy procedure for a definitive diagnosis. In the past, closed pleural needle biopsy (CPNB) has given poor yields due to the small amount of tissue obtained, and the patient has subsequently been subjected to a diagnostic thoracotomy. In recent years, the availability of more accurate histopathologic tests have enabled the pathologist to make a diagnosis more easily on samples obtained at CPNB.

Increased phosphorylation of elongation factor 2 in Alzheimer's disease.

Elongation factor 2 (EF-2) is a phosphoprotein that mediates the translocation step of elongation during protein synthesis. We investigated its phosphorylation to characterize translational regulation of gene expression in Alzheimer's disease. EF-2 was identified on two-dimensional (2D) gels of brain homogenates by analyzing immunoblots with EF-2-specific antibody (M(r) 96,000; pI 6.