thiobutabarbital and Respiratory-Tract-Diseases

Symptoms consistent with inhalation toxicity have long been associated with Florida red tides, and various causal agents have been proposed. Research since 1981 has centered on a group of naturally occurring trans-fused cyclic polyether compounds called brevetoxins that are produced by a marine dinoflagellate known as Karenia brevis. Numerous individual brevetoxins have been identified from cultures as well as from natural bloom events. A spectrum of brevetoxin derivatives produced by chemical modification of the natural toxins has been prepared to examine the effects of functional group modification on physiologic activity. Certain structural features of natural and synthetic derivatives of brevetoxin appear to ascribe specific physiologic consequences to each toxin. Differential physiologic effects have been documented with many of the natural toxins and derivatives, reinforcing the hypothesis that metabolism or modification of toxin structures modulates both the specific toxicity (lethality on a per milligram basis) and potentially the molecular mechanism(s) of action. A series of naturally occurring fused-ring polyether compounds with fewer rings than brevetoxin, known as brevenals, exhibit antagonistic properties and counteract the effects of the brevetoxins in neuronal and pulmonary model systems. Taken together, the inhalation toxicity of Florida red tides would appear to depend on the amount of each toxin present, as well as on the spectrum of molecular activities elicited by each toxin. Toxicity in a bloom is diminished by the amount brevenal present.

Topics: Animals; Dinoflagellida; Eutrophication; Florida; Humans; Inhalation Exposure; Marine Toxins; Oxocins; Public Health; Respiratory Tract Diseases; Risk Assessment; Structure-Activity Relationship; Thiopental

Cardiovascular disorders during endoscopy of the upper respiratory tract have since long induced anaesthetists and laryngologists to find a suitable anaesthetic procedure. It was the purpose of the present study to determine the influence exerted by different kinds of premedication and different modes of anaesthesia on the cardiovascular system, pO2, and the acid-base status. The results obtained show that a hypertensive-tachycardiac response to direct laryngo-tracheoscopy could not be prevented in any of the groups under investigation. Lowest blood pressure and heart rate increases were seen in those groups of patients which received an analgetic drug (Fentanyl or nitrous oxide) in addition to hexobarbital. During endoscopy, respiratory acidosis occurred in five groups of patients. All patients were sufficiently oxygenated.

Topics: Acid-Base Equilibrium; Adult; Anesthesia, General; Atropine; Blood Pressure; Bronchoscopy; Electrocardiography; Heart Rate; Hexobarbital; Humans; Laryngoscopy; Middle Aged; Oxygen; Preanesthetic Medication; Respiratory Tract Diseases; Succinylcholine; Thiopental