Biomedical subjects
Publications and source records attributed to Marinella Mazzone.
Asthma is a chronic reversible respiratory disease characterized by inflammation and bronchial smooth muscle contraction. The therapeutic approach must improve the acute symptoms, avoid disease exacerbations and prevent the pulmonary functional decay.
BACKGROUND: Cardiopulmonary bypass provokes a systemic inflammatory reaction that, in 1% to 2% of all cases, leads to multiorgan disfunction. The aim of this study was to evaluate the possible role of the intestine in the pathogenesis and development of this reaction. METHODS: Eleven selected patients scheduled for elective coronary artery bypass graft surgery were enrolled in a open, prospective clinical study. Gastric tonometry, chromium-labeled test and double sugar intestinal absorption tests, polymerase chain reaction microbial DNA test, and measurement of cytokines and transcriptional factor (nuclear factor kappaB) activation were performed. RESULTS: During the postoperative period, gastric pH remained stable (range,7.2 to 7.3). The partial pressure for carbon dioxide gradient between the gastric mucosa and arterial blood increased significantly (from 1 to 23 mm Hg), peaking in the sixth postoperative hour. Interleukin 6 increased significantly over basal levels, peaking 3 hours after cardiopulmonary bypass (96.3 versus 24 pg/mL). Nuclear factor kappaB never reached levels higher than those observed after lipopolysaccharide stimulation. Escherichia coli translocation was documented in 10 patients: in eight cases from removal of aortic cross-clamps and in two cases from the first postoperative hour. With respect to basal value (6.4%), the urine collection revealed a significant increase in excretion of the radioisotope during the first 24 hours after surgery (39.1%), although there were no significant variations with the double sugar test. CONCLUSIONS: The results obtained showed a correlation between the damage of the gastrointestinal mucosa, subsequent increased permeability, E coli bacteremia, and the activation of a self-limited inflammatory response in the absence of significant macrocirculatory changes and postoperative complications.
Torsade de pointes is a polymorphic ventricular tachycardia, associated with prolonged QT interval and characterized by twisting of the mean electrical axis of the QRS complexes around an isoelectric line. The long QT syndrome can be divided into two categories, congenital and acquired. The congenital long QT syndrome may be caused by some gene mutation, whereas the acquired form is usually associated with drugs and electrolyte imbalance. It usually remains asymptomatic or causes presyncope, although it may degenerate into ventricular fibrillation and may cause sudden death. The different presentation depends on the polymorphism that characterizes genotypic and phenotypic expression of proteic channel subunits, and on drug toxicity that provoke subunit dysfunction. The case report presented here is an example of prolonged QT interval syndrome in a patient with cocaine abuse and electrolyte disturbances.
In this paper the Authors consider the concept of stunning/hibernating myocardium, analizing the most recent articles and reviews in literature, until April 2002 (database PubMed). Dysfunctional segments with normal perfusion and normal glucose utilization are considered to be "stunned", and dysfunctional segments with reduced perfusion and preserved glucose utilization are considered to be "hibernated". Together with the two major hypothesis (generation of oxygen-derived free radicals and transient calcium overload) in developing of dysfunctional myocardium after ischaemia, recent studies have demonstrated an important role in down-regulation of beta-adrenergic receptors both in the stunned and in the hibernated segments. Moreover, the increase of negatively inotropic cytokines TNF-alpha and NOS2 has been observed in dysfunctional segments. The number of copies of mRNA has been quantified by reverse transcription-polymerase chain reaction (reverse-PCR).