ABSTRACT
The tissue reaction caused by a sintered tip electrode is compared with that of a platinum-iridium tip electrode in a work which employs implantation in sheep and follow-up of the implant for up to 90 days. Clinical tests and anatomo-pathological examination of the histological sections were performed. The results show a remarkably rapid fixation to the heart for the porous electrode with formation of limited inflammatory process, a thin fibrous capsule and modest alteration of the endocardial tissue. Conversely, the platinum-iridium electrode does not fix even in long periods and therefore continuously rubs the endocardial surface. Chronic inflammation and formation of remarkably thick connective capsule results, under which the heart seems mode deeply altered.
Subject(s)
Biocompatible Materials , Electrodes, Implanted , Endocardium/pathology , Pacemaker, Artificial , Animals , Iridium , Microscopy, Electron, Scanning , Platinum , SheepABSTRACT
In acute poisoning the main purpose of any therapeutic approach is a rapid removal of the drug or poison from body tissues. This approach suggested to undertake a study for the development of an uncoated activated carbon hemoperfusion column suitable for acute poisoning. Th clearances were significantly superior compared with a similar device manufactured using coated carbon. The microparticle generation, utilizing a spherical type of activated carbon, was undetectable with the adopted measuring method, well below the US and British Pharmacopeas limits and practically equal to a coated carbon column with identical geometry.
Subject(s)
Carbon/therapeutic use , Hemoperfusion/methods , Poisoning/drug therapy , Acute Disease , Adsorption , Animals , Blood Glucose , Blood Urea Nitrogen , Creatinine/blood , Humans , Inulin/blood , Particle Size , Phenobarbital/blood , Rabbits , Salicylates/blood , Salicylic Acid , Uric Acid/blood , Vitamin B 12/bloodABSTRACT
The Authors examine the functional, toxicological and pharmacological controls routinely performed on materials and on the finished products. They propose a biocompatibility protocol for screening materials, and they compare Italian regulations on quality control and good manufacturing practice of medical devices with foreign regulations.
Subject(s)
Pacemaker, Artificial/standards , Biocompatible Materials , Electrodes/standards , Humans , Italy , Quality Control , United StatesSubject(s)
Carbon , Electrolytes , Renal Dialysis/methods , Adult , Female , Humans , Kidneys, Artificial , Male , Middle AgedABSTRACT
The permeability of cellulose triacetate membrane coated activated charcoal is enhanced by treatment with KOH. The adsorption data for creatinine in aqueous solution before and after deacetylation are given. In order to study the usefulness of hemoperfusion associated with dialysis for removal of uremic toxins, some experiments were performed on the adsorption by coated and deacetylated charcoal of molecules of various molecular weights (from 113 to 40,000). Although the adsorption capacity of uncoated charcoal was better, the coated material still shows good properties in the adsorption of glucagon (mol wt 3485). The results on in vitro experiments of vitamin B12 removal by coated charcoal cartridge and CDAK Model 3 dialyzer confirms the usefulness of adsorption technique toward medium molecular weight compounds.
