Generation of polluted waters from mining wastes in a uranium deposit.

Dump consisting of 9500 tons of rich-in-pyrite mining wastes located in the uranium deposit Curilo, Western Bulgaria, was, after rainfall, an intensive source of acid drainage waters. These waters had a pH in the range of about 1.7-4.5 and contained radionuclides (uranium, radium), heavy metals (copper, zinc, cadmium, lead, nickel, cobalt, iron, and manganese), arsenic and sulphates in concentrations usually much higher than the relevant permissible levels for waters intended for use in the agriculture and/or industry. The generation of these polluted waters was studied under real field conditions for a period of about seven years during different climatic seasons. It was found that the dump was inhabited by a diverse microflora in which some acidophilic chemolithotrophic bacteria were the prevalent microorganisms. The solubilization of the above-mentioned pollutants from the dump material was connected mainly with the oxidation of pyrite and other sulphide minerals by these bacteria. Their activity depended on some essential environmental factors such as temperature, pH, and water, oxygen and nutrient contents in the dump.

Randomized, placebo-controlled phase II study of vandetanib plus docetaxel in previously treated non small-cell lung cancer.

PURPOSE: Vandetanib is a once-daily oral inhibitor of vascular endothelial growth factor receptor-2 and epidermal growth factor receptor kinase activity. The activity of vandetanib plus docetaxel was assessed in patients with previously treated non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: This two-part study comprised an open-label run-in phase and a double-blind randomized phase. Eligible patients had locally advanced or metastatic (stage IIIB/IV) NSCLC after failure of first-line platinum-based chemotherapy. The primary objective of the randomized phase was to prolong progression-free survival (PFS) in patients receiving vandetanib (100 or 300 mg/d) plus docetaxel (75 mg/m2 intravenous infusion every 21 days) versus placebo plus docetaxel. The study was designed to have more than 75% power to detect 50% prolongation at a one-sided significance level of P < .20. Secondary objectives included objective response rate, overall survival, safety and tolerability. RESULTS: In the randomized phase (n = 127), median PFS was 18.7 weeks for vandetanib 100 mg plus docetaxel (n = 42; hazard ratio v docetaxel = 0.64; one-sided P = .037); 17.0 weeks for vandetanib 300 mg plus docetaxel (n = 44; hazard ratio v docetaxel = 0.83; one-sided P = .231); and 12 weeks for docetaxel (n = 41). There was no statistically significant difference in overall survival among the three treatment arms. Common adverse events included diarrhea, rash, and asymptomatic prolongation of corrected QT (QTC) interval. CONCLUSION: The primary objective was achieved, with vandetanib 100 mg plus docetaxel demonstrating a significant prolongation of PFS compared with docetaxel in relation to the prespecified significance level. On the basis of these encouraging data, phase III evaluation of vandetanib 100 mg plus docetaxel in second-line NSCLC has been initiated.

Management of benign stenoses of the large airways in the university hospital in Prague, Czech Republic, in 1998-2003.

BACKGROUND: Clinically significant benign stenoses of the large airways develop in about 1% of patients after intubation. The management of benign stenoses is not unified around the world, nor are there any accepted methods for their screening. OBJECTIVES: The purpose of this study is to describe and compare results of interventional bronchoscopy and surgical therapy of benign stenoses as well as to propose an algorithm for the management of this airways disorder. METHODS: Prospective study on 80 consecutive patients with benign stenoses of the large airways admitted to the Pulmonary Department of the University Hospital of Prague-Motol. RESULTS: Sixty-two patients developed stenoses after endotracheal intubation or tracheostomy, in 18 patients the stenosis was caused by other diseases or pathological situations. Thirty-eight patients were sent for surgical resection of the stenotic part of the airways. 2 surgically treated patients developed recurrence of the stenosis and had to be reoperated on. Narrowing of the trachea at the site of end-to-end anastomosis developed in 6 other patients and was cured by interventional bronchoscopy. The remaining 42 patients were treated by interventional bronchoscopy (Nd-YAG laser, electrocautery, stent) which was curative in 35 patients. Sixty-five patients were alive at the time of evaluation, 15 patients died. Five of them died between 3 and 14 (median 4) months after surgery from a disease other than airway stenosis. Ten nonresected patients also died, with 1 exception, due to a disease other than airway stenosis; the median survival was 9 months. CONCLUSIONS: We recommend to assess the patient for surgery after the initial diagnosis and therapeutic bronchoscopy with dilatation of the stenosis. If the patient is not a suitable candidate for resection, interventional bronchoscopy is an appropriate alternative for the management of benign stenoses of the large airways.