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The recovery of critical and precious metals from waste electrical and electronic equipment (WEEE) is an environmental and economic imperative. Biosorption has been considered a key technology for the selective extraction of gold from hydrometallurgical liquors obtained in the chemical leaching of e-waste. In this work, the potential of tannin resins prepared from Pinus pinaster bark to sequester and recover gold(III) from hydrochloric acid and aqua regia solutions was assessed. Equilibrium isotherms were experimentally determined and maximum adsorption capacities of 343 &plusmn, 38 and 270 &plusmn, 19 mg g&minus, 1 were found for Au uptake from HCl and HCl/HNO3 (3:1 v/v) solutions containing 1.0 mol L&minus, 1 H+. Higher levels of acidity (and chloride ligands) significantly impaired the adsorption of gold from both kinds of leaching solutions, especially in the aqua regia system, in which the adsorbent underperformed. Pseudo-first and pseudo-second order models successfully described the kinetic data. The adsorbent presented high selectivity towards gold. Actually, in simulated aqua regia WEEE liquors, Au(III) was extensively adsorbed, compared to Cu(II), Fe(III), Ni(II), Pd(II), and Zn(II). In three adsorption&ndash, desorption cycles, the adsorption capacity of the regenerated adsorbent moderately decreased (19%), although the gold elution in acidic thiourea solution had been quite limited. Future research is needed to examine more closely the elution of gold from the exhausted adsorbents. The results obtained in this work show good perspectives as regards the application of pine bark tannin resins for the selective extraction of Au from electronic waste leach liquors.

Intracapsular carcinomas ex pleomorphic adenoma are exceedingly rare salivary glands tumours, known to have a benign clinical behaviour with metastatic unrecognised potential. We report a case of a 57-year-old female patient presenting with a typical example of intracapsular carcinoma ex pleomorphic adenoma of the parotid gland and evidence of ipsilateral cervical lymph node metastases two years before. The behaviour of this unique case illustrates the disputed malignancy of carcinomas arising within encapsulated pleomorphic adenomas.

The case of a parathyroid carcinoma in a 61-year-old woman is described. The patient was referred to our hospital, with the diagnosis of medullary thyroid carcinoma, after a prior thyroidectomy performed at another hospital. On admission, serum calcium was 3.92 mmol/l (n.r. 2.2-2.5), PTH level was 320 ng/l (n.r. 10-65), urinary cAMP was 508.9 mmol/mmol creatinine (n.r. 330- 630) and serum calcitonin was 2.1 ng/l (n.r.

Auto-antibodies such as anti-elastin, anti-collagen, anti-nuclear and anti-arterial, circulating immune complexes, and cellular responses to collagen I and III are known to be present in Buerger's disease (EO). Deposits of IgG, C3 and C4 have also been found in the vascular lesions of endarteritis obliterans (EO) in young men. The purpose of this study was to correlate clinical evidence of vascular disease with the presence of the circulating immune complexes. Thirty-three patients suffering from Buerger's disease (EO), 20 patients suffering from atherosclerosis (AT) and 20 normal controls (Norm) were studied. All were male, heavy smokers, and age-matched. Five techniques were used: direct nephelometry, nephelometry with protamine, two polyethyleneglycol precipitation methods (PegIgG and PegC4), and an immuno-enzymatic C1q fixation test (C1qE). The results seem to confirm the presence of circulating immune complexes in peripheral arterial disease in young men who are heavy smokers, particularly those suffering from EO.

Adrenaline was incubated with dog plasma in concentrations ranging from 50 to 1,000 ng/ml and binding to plasma proteins was found to be about 12% (8, 12 or 14%, as determined by spectrophotofluorimetric, liquid scintillation or Sephadex G-50 gel filtration methods, respectively). For isoprenaline, the binding to plasma proteins was of about 14-18%, as shown by liquid scintillation or Sephadex G-50 gel filtration methods. Cellulose acetate electrophoresis demonstrated that albumin does not play any significant role in this binding, in the case of both adrenaline and isoprenaline. These results show that adrenaline and isoprenaline are much less bound to proteins that noradrenaline (40%). It is concluded that the N substitution present in adrenaline and isoprenaline appears to be responsible for the different degrees of protein binding.