Combination balloon-ultrasound imaging catheter for percutaneous transluminal angioplasty. Validation of imaging, analysis of recoil, and identification of plaque fracture.

Background: We investigated the hypothesis that an ultrasound transducer positioned within an angioplasty balloon could be used to perform quantitative assessment of arterial dimensions before and after percutaneous transluminal angioplasty (PTA) and to identify certain mechanical alterations consequent to PTA, including vascular wall recoil and the initiation of plaque fractures.

Methods And Results: A combination balloon-ultrasound imaging catheter (BUIC) that houses a 20-MHz ultrasound transducer within and halfway between the proximal and distal ends of an angioplasty balloon was used to perform PTA in 10 patients with peripheral vascular disease. Each PTA site was also evaluated before and after PTA by standard (nonballoon) intravascular ultrasound (IVUS) technique.

Molecular identification of a major palmitoylated erythrocyte membrane protein containing the src homology 3 motif.

The complete amino acid sequence of a 55-kDa erythrocyte membrane protein was deduced from cDNA clones isolated from a human reticulocyte library. This protein, p55, is copurified during the isolation of dematin, an actin-bundling protein of the erythrocyte membrane cytoskeleton. Fractions enriched in p55 also contain protein kinase activity that completely abolishes the actin-bundling property of purified dematin in vitro.

Spinal cord compression secondary to extramedullary hematopoiesis: a noninvasive management based on MRI.

We report the first case of spinal cord compression secondary to extramedullary hematopoiesis in which the diagnosis was made by magnetic resonance imaging (MRI). Based on the great advantage of this imaging test that visualizes the entire spine, the noninvasive approach to such patients, using low-dose radiation therapy and guided by MRI is discussed. This management appears to be both efficacious and safe.

Aggressive malignant hemangiopericytoma in the neck.

Hemangiopericytomas are rare vascular tumors, one fourth of which occur in the head and neck. These lesions are characteristically slow growing and slow to metastasize. We describe an otherwise healthy patient with a hemangiopericytoma on the left side of his neck that metastasized to his chest wall within 3 months after the tumor was first observed.

Organization of the gene for human erythrocyte membrane protein 4.2: structural similarities with the gene for the a subunit of factor XIII.

Human erythrocyte band 4.2 is a major membrane-associated protein with an important, but still undefined, role in erythrocyte survival. We previously sequenced the complete cDNA for band 4.

Sodium inhibits hormone release and stimulates calcium efflux from isolated nerve endings of the rat neurohypophysis.

1. We studied the effects of extracellular sodium on the secretion of vasopressin (VP) and oxytocin (OT) and the efflux of 45Ca from isolated, perfused nerve endings of the rat neurohypophysis (neurosecretosomes). 2.

Hypernatremia due to repeated doses of charcoal-sorbitol.

Hypernatremic dehydration due to unreplaced stool water losses often complicates the use of the osmotic cathartic lactulose in the treatment of hepatic encephalopathy. Sorbitol, another osmotic cathartic commonly used in the treatment of drug intoxications, has been reported in the pediatric literature to induce severe hypernatremia, but there is only a rare case report in an adult. We report a dramatic case of severe hypernatremia secondary to repetitive administration of activated charcoal-sorbitol suspension for the treatment of phenobarbital intoxication in an adult.

Acute catastrophic complications of balloon aortic valvuloplasty. The Mansfield Scientific Aortic Valvuloplasty Registry Investigators.

Among the initial 492 patients who underwent balloon aortic valvuloplasty as part of the Mansfield Investigational Device Exemption Protocol, 31 (6.3%) had acute catastrophic complications. These included ventricular perforation in nine (1.

Uncoupling of the spectrin-based skeleton from the lipid bilayer in sickled red cells.

The distribution of spectrin and band 3 in deoxygenated reversibly sickled cells was visualized by immunofluorescence and immunoelectron microscopy. Antibodies against band 3, the major lipid-associated transmembrane protein, labeled the entire cell body, including the entire length of the long protruding spicule, whereas antibodies against spectrin labeled only the cell body and the base region of the spicules. The results suggest that the formation of long spicules during sickling is associated with a continuous polymerization of hemoglobin S polymers, presumably through gaps in the spectrin-actin meshwork, and a subsequent uncoupling of the lipid bilayer from the submembrane skeleton.

Malaria and ovalocytosis--molecular mimicry?

Two recently published reports have described findings which will have a profound impact on the understanding of molecular mechanisms of human resistance to malaria infection. In Melanesian ovalocytosis, a genetic polymorphism found in Papua New Guinea and parts of South East Asia, the red cells are highly resistant to invasion by various species of malaria parasite. The molecular nature of the defect in ovalocytic erythrocytes was not known.

A hospital-based chemotherapy education and training program.

Impatient chemotherapy administered by nurses from the outpatient setting causes fragmentation of care by impeding the primary nursing model. The inpatient oncology nursing staff, highly motivated to expand their knowledge base for cancer patient care, expressed interest in chemotherapy administration. In a collaborative effort among the oncology clinical nurse specialist, nurse educator, and nurse manager, a program was designed based on The Oncology Nursing Society Cancer Chemotherapy Guidelines and Recommendations for Nursing Education and responses from an education-needs assessment survey.

Factors influencing postoperative urinary retention in patients undergoing elective inguinal herniorrhaphy.

We retrospectively studied 295 men who had undergone herniorrhaphy under spinal or general endotracheal anesthesia to determine the incidence of postoperative urinary retention and to assess factors influencing it. The type and location of hernia had no effect on retention. In contrast, the use of general anesthesia, patient age above 53 years, and perioperative administration of more than 1,200 mL of fluid were significantly associated with an increase in retention.

Infected necrosis: morbidity and therapeutic consequences.

Some 20% of cases of acute pancreatitis are associated with pancreatic and/or peripancreatic necrosis. Mortality of necrotizing pancreatitis is higher than that of acute interstitial pancreatitis, especially if there is secondary pancreatic infection. Despite the fact that patients with infected necrosis are in general more seriously ill than those with sterile necrosis, it is not possible at present by any individual laboratory test or constellation of tests to determine precisely which patients are infected or will develop pancreatic infection.

Activation of phosphatidylinositol 3-kinase in cells expressing abl oncogene variants.

A phosphoinositide kinase specific for the D-3 position of the inositol ring, phosphatidylinositol (PI) 3-kinase, associates with activated receptors for platelet-derived growth factor, insulin, and colony-stimulating factor 1, with products of the oncogenes src, fms, yes, crk, and with polyomavirus middle T antigen. Efficient fibroblast transformation by proteins of the abl and src oncogene families requires activation of their protein-tyrosine kinase activity and membrane association via an amino-terminal myristoylation. We have demonstrated that the PI 3-kinase directly associates with autophosphorylated, activated protein-tyrosine kinase variants of the abl protein.

Transcriptional control of muscle proteins.

The development of a muscle cell from a precursor cell involves a massive adjustment of gene expression such that over 50 previously silent genes are expressed to produce the muscle proteins required for contractile functions. In differentiated muscle, hormonal and physiologic stimuli modify the expression of these proteins primarily at the level of transcription. How does the cell regulate the switching on and switching off of specific genes to produce the muscle phenotype and respond to new conditions?

Cardiac complications of cocaine abuse.

Cocaine abuse is now firmly associated with several cardiac complications. Acute myocardial infarction is the best documented of these complications and appears to result from cocaine-induced coronary arterial spasm. Myocarditis and/or cardiomyopathy have also been reported in a smaller number of patients.

Length of stay in a general hospital psychiatric unit.

Fifty psychiatric inpatients with a prolonged length of stay were compared to 50 control admissions for factors associated with prolonged hospitalizations in a general hospital. Seven variables were found to be significantly overrepresented among the long stayers, including treatment with electroconvulsive therapy, medical consultations, underemployment, dementia, disposition to a place other than home, absence of alcohol or drug abuse, and presence of psychosis without affective symptoms. The clinical and policy implications of these finding are discussed.

Abnormal protein in the cerebrospinal fluid of patients with a submicroscopic X-chromosomal deletion associated with Norrie disease: preliminary report.

Norrie disease is an X-linked recessive disorder characterized by congenital blindness and, in many cases, mental retardation. Some Norrie disease cases have been shown to be associated with a submicroscopic deletion in chromosomal region Xp11.3.

Analysis of photoproducts, free radicals, and particulate debris generated during in vivo argon laser myoplasty.

Catheter-guided laser myoplasty in a closed ventricle has been advocated for the treatment of hypertrophic cardiomyopathy, ablation of arrhythmogenic foci, and transmyocardial laser revascularization of ungraftable regions of ischemic myocardium. The purpose of this study was to evaluate the nature of particulate debris and photoproducts generated in vivo. Accordingly, cardiopulmonary bypass was established in four dogs without active cooling and an apical left ventricular vent was placed.

Predictors of severity in acute pancreatitis.

Accurate predictors of severity in acute pancreatitis are sorely needed. At present, Ranson's scores provide useful information, some of which is recorded too late to be of maximal usefulness. APACHE-II scores on the day of admission and thereafter appear to provide important prognostic information that may enable the clinician to optimize patient care.