High-grade undifferentiated pleomorphic sarcoma of the aortic arch: a case of endovascular therapy for embolic prophylaxis and review of the literature.

Primary malignant tumors of the aorta (PMTAs) are an extremely rare clinical entity. In most cases, the diagnosis is made either postmortem or late in the course of disease due to a low index of clinical suspicion and presenting symptoms that mimic far more common athero-embolic processes. Due to the intravascular origin of these tumors, peripheral and mesenteric embolic events represent a major source of morbidity and mortality.

Mechanisms of vasoactive intestinal peptide-elicited coronary vasodilation in the isolated perfused rat heart.

The present study investigated the potential role of vasoactive intestinal peptide (VIP) receptors, VPAC1 and VPAC2, in VIP-elicited coronary vasodilation of the isolated perfused rat heart. Additional studies determined the role of ATP-sensitive (K(ATP)) and voltage-gated K(+) (K(V)) channels in the VIP-elicited coronary vasodilation. Both the selective VPAC1 agonist, K15,R16,L27VIPl-7GRF8-27, and the selective VPAC2 agonist, RO25-1553, decreased coronary vascular resistance (CVR) in a dose-dependent manner, with EC(50) values of 1.

Coronary vascular effects of vasoactive intestinal peptide in the isolated perfused rat heart.

The potency and mechanism of action of vasoactive intestinal peptide (VIP) for producing coronary vasodilation was investigated in the isolated perfused heart of the rat. VIP reduced coronary vascular resistance in a dose-dependent manner, starting at 1 x 10(-10) M, and maximally reduced coronary vascular resistance by 49% at 1 x 10(-8) M. The potency of VIP for reducing coronary vascular resistance (EC50=3.

A prospective, randomized, study comparing early percutaneous dilational tracheotomy to prolonged translaryngeal intubation (delayed tracheotomy) in critically ill medical patients.

Objective: The timing of tracheotomy in patients requiring mechanical ventilation is unknown. The effects of early percutaneous dilational tracheotomy compared with delayed tracheotomy in critically ill medical patients needing prolonged mechanical ventilation were assessed.

Design: Prospective, randomized study.

Corticotropin-releasing hormone increases the expression of the prostaglandin E(2) receptor subtype EP1 in amnion WISH cells.

The purpose of this study was to investigate the effect of corticotropin-releasing hormone (CRH) on the expression of the prostaglandin (PG) E(2) EP1 receptor subtype and PGE(2) production in amnion WISH cells (AWC). AWC cultures were incubated with CRH. Culture fluid was collected for PGE(2) measurement, and the cells were collected and analyzed for EP1 protein and mRNA.

Immunohistochemical localization of the prostaglandin E subtype-1 receptor in cytokine-stimulated and unstimulated amnion cells.

Objective: To visualize histochemically the prostaglandin EP1 receptor in human amnion cells and to study the effect of inflammatory cytokines, which are known to stimulate the EP1 receptor, on localization.

Methods: Immortalized amnion cells, grown on standard microscope slides and either nonstimulated (control) or stimulated by incubation in culture medium containing interleukin-1beta (25 ng/mL), interleukin-4 (50 ng/mL), or tumor necrosis factor alpha (25 ng/mL), were incubated with rabbit anti-human EP1 antibody and stained by a two-step indirect immunoperoxidase strepavidin-biotin method using horseradish peroxidase and 3,3' diaminobenzidine as the chromogen. The localization was done on ten different flasks of cells.

Modulation of the prostaglandin E receptor: a possible mechanism for infection-induced preterm labor.

Objective: To evaluate the modulatory effects of interleukin (IL)-1beta and prostaglandin (PG)E2 on the PGE2 receptor subtype EP1 in amnion cell cultures.

Methods: Amnion cell cultures were incubated in increasing concentrations of (IL)-1beta or PGE2. Cultures were also incubated in high concentrations of IL-1beta and PGE2 in combination.

Tumor necrosis factor-alpha upregulates the prostaglandin E2 EP1 receptor subtype and the cyclooxygenase-2 isoform in cultured amnion WISH cells.

Recent studies have demonstrated a strong correlation between infection and preterm labor. Preterm delivery is also associated with high levels of cytokines and prostaglandins in amniotic fluid. The purpose of this study was to investigate the effect of tumor necrosis factor-alpha (TNF-alpha) on the levels of cyclooxygenase, prostaglandin E2 production (PGE2), and expression of the PGE2 receptor subtype EP1 in amnion WISH cell culture.

Fibronectin and the extracellular matrix in the perforating disorders of the skin.

Despite detailed microscopic descriptions and clinical observation, little is known regarding the pathogenesis of the perforating disorders of skin, which have traditionally been subdivided into numerous microscopic entities associated with various clinical settings. An increasing body of evidence now suggests that the perforating disorders of skin are akin, and may constitute an expanded single pathologic entity. Each of the classic perforating disorders of skin, including elastosis perforans serpiginosa, perforating folliculitis, reactive perforating collagenosis, Kyrle's disease, and perforating disorder of uremia, have been shown to extrude collagen, elastin, and related extracellular matrix components through the epidermis.

The induction of cyclooxygenase-2 by interleukin-4 in human umbilical vein endothelial cells: a possible role in regulation of fetal vascular tone.

Objective: We sought to determine a possible role for interleukin-4 in the control of umbilical cord blood flow by evaluating its effect on cyclooxygenase-2 production of a vasoactive prostaglandin.

Study Design: Human umbilical vein endothelial cells in culture were incubated for 16 hours in media containing interleukin-4 in concentrations from 5 to 100 ng/ml. Prostaglandin E2 concentrations in the culture media were measured using a monoclonal enzyme-immunoassay.

Signal transduction: activation of the guanylate cyclase-cyclic guanosine-3'-5' monophosphate system by hormones and free radicals.

Intracellular communication and transmission of messages for many hormones and free radicals occur after the hormones and free radicals bind to their receptors by enhancing the activity of guanylate cyclase, the enzyme that catalyzes the conversion of guanosine triphosphate to the intracellular messenger cyclic guanosine-3'-5' monophosphate (cyclic GMP). The guanylate cyclase-linked receptors exist intracellularly (ie, cytoplasmic) and in membrane-bound forms. Enhancement of guanylate cyclase by hormones or free radicals increases intracellular cyclic GMP, which closes cation channels in the kidney while activating cation channels in the retina and olfactory cilia, either directly or by cyclic GMP-dependent protein kinase.

Survival of rat and porcine Sertoli cell transplants in the rat striatum without cyclosporine-A immunosuppression.

The use of cyclosporine-A (CsA) immunosuppression for neural transplantation has become the treatment of choice for ameliorating host-graft rejection responses in human and animal transplant studies. However, the cytotoxic effects of CsA have warranted a search for alternative methods of protecting neural transplants. Sertoli cells produce an immunosuppressant factor, Fas ligand (Fas-L), that may provide the testis with its immunoprivileged status.

The induction of cyclooxygenase-2 (COX-2) in intact human amnion tissue by interleukin-4.

Infection is a major cause of preterm labor. Amniotic fluid from women in preterm labor associated with intrauterine infection contains increased concentrations of cytokines. The mechanism underlying this association may be a cytokine-mediated stimulation of amnion cell prostaglandin production.

Enuresis in sickle cell disease.

The prevalence of enuresis and management options for this condition were studied in our population of sickle cell patients. A total of 91 active patients (6 to 21 years old) followed at our regional sickle cell center was surveyed for the symptoms of primary nocturnal enuresis. Of the 91 patients 27 (29.

Depletion of surfactant tubular myelin with pulmonary dysfunction in a rat model for acute endotoxemia.

Although prolonged Gram-negative sepsis with high permeability alveolar edema, a well documented cause of adult respiratory distress syndrome, has been shown to result in surfactant alterations, the effects of acute endotoxemia on the lung surfactant system are largely unknown. In this study, lethal endotoxemia (> 80% mortality at 24 h) resulting in severe, rapid leukopenia with progressive thrombocytopenia was achieved through intraperitoneal injection of adult Fischer 344 rats with 3.5 mg of Escherichia coli endotoxin/kg.

Atrial natriuretic peptides are present throughout the plant kingdom and enhance solute flow in plants.

The present investigation was designed to 1) determine if atrial natriuretic-like peptides are present throughout the plant kingdom and 2) to determine if these peptides increase the flow of solute and/or water upward to leaves and flowers of plants. The 126-amino acid prohormone of atrial natriuretic factor (proANF)-(1-30), proANF-(31-67), and atrial natriuretic factor (ANF)-like peptides were present in the roots, stems, leaves, and flower petals of the more highly developed plants (Tracheophyta), with their highest concentrations being: Florida beauty > buddhist pine > Boston fern > rose = geranium = resurrection plant or club moss > Moses-in-the-cradle > Florida coontie. These peptides were also present in Bryophata (plants without vascular tissue or roots) and even in Euglena, flagellated chlorophyll-containing plants without leaves, stems, or roots.

Adrenal receptors for natriuretic peptides and inhibition of aldosterone secretion in calf zona glomerulosa cells in culture.

Atrial and brain natriuretic peptides specifically bind to primary cultures of calf adrenal glomerulosa cells. Binding of both natriuretic peptides to the same receptor has been proved by: a Dixon plot showing competitive effects for the binding of 125I-labeled brain natriuretic peptide in the presence of increasing concentrations of unlabeled atrial natriuretic peptide; a Scatchard plot showing a lower dissociation constant (Kd) for atrial natriuretic peptide than for brain natriuretic peptide binding, but the maximum binding (Bmax) values were the same; autoradiography of sodium dodecyl sulfate polyacrylamide gels after cross-linking of 125I-labeled atrial natriuretic peptide and 125I-labeled brain natriuretic peptide, showing the same molecular weights for both peptide receptors--a single 66-kD band in whole cells and a main band at 125 kD in membranes. C-Type atrial natriuretic peptide only slightly displaced atrial natriuretic peptide binding.

Specific binding site for pro atrial natriuretic factors 1-30, 31-67, and 99-126 on distal nephrons, proximal tubules, renal cortical and medullary membranes.

Two peptides with natriuretic and diuretic properties consisting of amino acids (a.a.) 1-30 and 31-67 of the 98 a.

Evaluation of an improved sampling method for blood gas analysis from indwelling arterial catheters.

Embolic complications of indwelling arterial lines are well documented. We evaluated a method of blood sampling from indwelling arterial lines that minimizes blood loss and eliminates the embolic risks associated with retrograde flushing. The values for PaO2, PaCO2, and pH obtained by the conventional sampling technique were compared to those obtained by a technique termed the "three drop" method.