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Absence of D147E mutation of CYP11B2 gene in hypertensive patients with increased corticosterone and aldosterone production.
No full textAbsence of D147E mutation of CYP11B2 gene in hypertensive patients with increased corticosterone and aldosterone production.
Mulatero P1, Glorioso N, Fallo F, Soro A, Morra di Cella S, Carra R, Filigheddu F, Veglio F.
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Abstract
OBJECTIVE:
11beta-Hydroxylase and aldosterone synthase are two highly homologous genes involved in different forms of human hypertension and in different animal models of hypertension. It has been shown that the conservative substitution D147E in the human CYP11B2 gene results in an increased production of corticosterone and aldosterone in vitro. A gene conversion between the CYP11B1 and CYP11B2 genes could be responsible for such a substitution.
METHODS:
In this study we investigated the presence of the mutation D147E of CYP11B2 in a group of 128 patients with primary aldosteronism, 68 patients with essential hypertension and increased corticosterone production and in 48 normal volunteers.
RESULTS AND CONCLUSIONS:
We did not identify any patient carrying this mutation, indicating that if it exists it is very rare and so has no relevance in determining the increased steroid excretion seen in some subtypes of human hypertension
Kinetic modelling of pyrrothite ore leaching by ferric iron and related statistical analysis
No full textSimulation and economic analysis of a hydrometallurgical approach developed for the treatment of waste printed circuit boards (WPCB)
No full textThis paper presents the main achievements of a hydrometallurgical process to recover base and precious metals from waste printed circuit boards (WPCB). The technology comprises a first leaching process performed in a two-step counter current way with sulfuric acid and hydrogen peroxide for base metals solubilization and a consecutive cross leaching process with thiourea, ferric sulfate and sulfuric acid to extract precious metals. Furthermore, the reach solutions are subjected to cementation procedure with zinc powder to recover the elements of interests as metal powders. The spent solution achieved after cementation of precious metals is partially recycled within the process and the other part is treated by Fenton process and then neutralized with lime. Considering the achieved results at the laboratory level, the entire procedure was simulated using SuperPro Designer software to determine the process economy for an industrial plant. Besides this, the use of this software allows achieving the material balance of a process and the design of the plant. As a result, the process implementation at a larger scale is simulated and the main issues that can result in such a case can be determined and solved
Overview on hydrometallurgical procedures for silver recovery from various wastes
No full textThe core of this paper is to expose the current situation on generation and treatment of five streams that present Ag in their composition. During the last two decades, large amounts of silver recovered from primary ores has been used in the manufacturing of electrical and electronic devices. Between these devices, the current situation for printed circuit boards (component which is found in each device that make use of an electrical field) and spent plasma monitors is shown. Moreover, the button cells, which are a special category of waste at the end of their life, are also presented within this article. The spent effluents of photographic industry, X-Ray films and laboratory waste represent two other important secondary resource of silver and therefore their situation and current hydrometallurgical methods of processing will be also present within this paper
Study of multi-step hydrometallurgical methods to extract the valuable content of gold, silver and copper from waste printed circuit boards
No full textIn this work, hydrometallurgical methods like counter and cross current chemical leachings and cementation have been studied and applied for copper, gold and silver recovery from waste printed circuit boards. 1.7 M H2SO4 (98% wt./vol.), 17% (V/V) H2O2 (30 wt./vol%.), solid/liquid ratio of 15 g/L, room temperature, with a continuous stirring rate of 200 rpm for 1 h have been the optimal conditions for Cu dissolution by the two-step counter current leaching procedure. The cross current leaching procedure with thiourea as reagent and triferric ion as oxidizing agent in diluted acid sulfuric media were involved for the dissolution of gold and silver. About 90% of Au and 75% of Ag extraction yield were obtained in the first step with 20 g/L of thiourea, 6 g/L of ferric ion, 0.1 M of sulfuric acid with a vigorous agitation of 200 rpm of 1 h at ambient temperature. In the solutions purification step, high recovery rates of both Cu and precious metals have been achieved by applying cementation process with Zn powder. This procedure can be considered of interest and is under continuously development for a further application on a small hydrometallurgical pilot plant
Study on the influence of various factors in the hydrometallurgical processing ofwaste electronic materials for gold recovery
No full textIl ruolo della terapia di combinazione nellâ€TMacquisizione degli obiettivi terapeutici: i risultati dei grandi trials.
No full textEmpirical models for oxygen mass transfer: a comparison between shake flask and lab-scale fermentor and application to manganiferous ore bioleaching.
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