Plutonium-238 nitrate was accidentally deposited in a puncture wound of the right index finger of an employee at the Savannah River Plant Radiochemical Separations Facility in November 1968. A comprehensive treatment and evaluation program was initiated immediately and has continued for more than 2 yr. Postaccident treatment included immediate use of a venous tourniquet; flushing and decontaminating the wound site; excising tissue; and administering chelating agents (intravenously, orally and by aerosol inhalation). The plutonium injection and assimilation was assessed by wound monitoring ; whole-body counting; and an extensive biosassay program (blood, urine and feces). The plutonium body burden is estimated to be 31 nCi, but complications were encountered in making this estimate because of the use of chelating agents and the lack of information about the movement of plutonium nitrate from the wound site.

No abstract

No abstract

No abstract

Currently, various modifications to surfaces are made more and more frequently in order to improve implants' haemocompatibility. The main criterion determining the applicability of the respective surface-modification method is obtaining a product featuring suitable functional properties. These properties depend to a great extent on the corrosion resistance in the environment of human blood. Subject-matter literature does not devote much attention to the sterilisation process for titanium and cpTi alloys with surface modifications. A problem that still remains unsolved is the selection of a proper test showing the full characteristics of their behaviour contact with a blood environment during the time that the implant is used. Therefore, the authors of this study made an attempt to evaluate the impact of medical sterilisation methods, i.e., the ethylene oxide anodic oxide and SiO2 layer, by means of the sol-gel method. The efficiency of the suggested technology for oxide layer application was evaluated on the basis of mechanical and electrochemical tests. Sterilisation in ethylene oxide and steam had a favourable influence on the electrochemical and mechanical properties of cpTi, irrespective of the method of surface preparation. In order to simulate real conditions, the tests were performed in artificial plasma at a temperature of T = 37 ± 1°C and pH = 7.0 ± 0.2. The results proved the diversification of electrochemical properties of the oxide layers, depending on the technological parameters of its application. The suggestion of proper variants of the surface modification with the application of electrochemical and chemical methods is of long-range importance and will contribute to the development of technological conditions with specific parameters for the creation of oxide layers on metallic implants made of cpTi. Keywords: cpTi (Grade 4), SiO 2 , TiO 2 , mechanical properties, electrochemical properties Vedno pogosteje se opravljajo razli~ne modifikacije povr{ine, da bi se izbolj{ala hemokompatibilnost vsadkov. Glavni kriterij, ki dolo~a uporabnost metode za modifikacijo povr{ine je, da proizvod poka`e primerne funkcionalne lastnosti. Te lastnosti so v veliki meri odvisne od korozijske odpornosti v~love{ki krvi. Obstoje~a literatura ne posve~a velike pozornosti postopku sterilizacije titana in cpTi zlitin z modificirano povr{ino. Problem, ki {e ni re{en, je izbira primernega preizkusa, ki bi pokazal vse zna~ilnosti o obna{anju stika s krvjo med uporabo vsadka. Zato so avtorji v tej {tudiji poizkusili oceniti vpliv medicinskih metod sterilizacije, kot je etilen oksid anodni oksid in SiO2 plast izdelano s pomo~jo metode sol-gel. Predlagana tehnologija uporabe oksidnega sloja je bila ocenjena z mehanskimi in elektrokemijskimi preizkusi. Sterilizacija v etilen oksidu in pari je imela ugodne vplive na elektrokemijske in mehanske lastnosti cpTi, ne glede na na~in priprave povr{ine. Za simulacijo realnih pogojev so bili preizkusi izvr{eni v umetni plazmi pri temperaturi T = 37 ± 1°C in pH = 7,0 ± 0,2. Dobljeni rezu...

Titanium and its alloys are characterized by high biocompatibility and good corrosion resistance as a result of the ability to form a TiO2 oxide layer. However, based on literature data it can be concluded that titanium degradation products, in the form of titanium particles, metal-protein groups, oxides and ions, may cause allergic, inflammatory reactions and bone resorption. The corrosion process of Ti6Al4V in the human body environment may be intensified by a decreased pH and concentration of chloride compounds. The purpose of this article was to analyze the corrosion resistance of the Ti6Al4V alloy, obtained by the selective laser melting method in a corrosion solution of neutral pH and in a solution simulating peri-implant inflammatory conditions. Additionally, the influence of zinc oxide deposited by the atomic layer deposition method on the improvement of the physicochemical behavior of the Ti6Al4V alloy was analyzed. In order to characterize the ZnO layer, tests of chemical and phase composition as well as surface morphology investigation were performed. As part of the assessment of the physicochemical properties of the uncoated samples and those with the ZnO layer, tests of wetting angle, pitting corrosion and impedance corrosion were carried out. The number of ions released after the potentiodynamic test were measured using the inductively coupled plasma atomic emission spectrometry (ICP–AES) method. It can be concluded that samples after surface modification (with the ZnO layer) were characterized by favorable physicochemical properties and had higher corrosion resistance.

No abstract

No abstract