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Biosynthesis of silver nanoparticles using Penicillium fungi has been reported. The extracellular mechanism of silver nanoparticles creation was investigated by UV-Vis spectroscopy, electron microscopy and laser diffraction. The zeta potential of silver nanoparticles has also been determined. [ABSTRACT FROM AUTHOR]

The extraction of iron(III) from chloride solutions has been investigated using N,N'-dimethyl-N,N'-diphenylhexylmalonamide (DMDΦ(H)MA), N,N'- dimethyl-N,N'-diphenyldodecylmalonamide (DMDΦ(D)MA), N,N'-dimethyl-N,N'-dicyclohexylmalonamide (DMDCMA) and N,N'-dimethyl-N,N'-dihexylmalonamide (DMDHMA). The main aim of this work was to investigate whether there is a relation between the chemical structure of malonamides and their iron(III) extraction behavior, and to try to understand the dependence of the metal extraction mechanism on the structural characteristics of the malonamides. The introduction of an alkyl chain on the central carbon atom of N,N'-dimethyl-N,N'-diphenyl skeleton malonamides increases the affinity of the organic derivatives for iron(III) at lower hydrochloric acid concentrations: the longer the alkyl chain, the lower the acidity of half of the extraction of iron(III) is. A similar behavior has been observed both for DMDCMA and DMDHMA when N,N'-dimethyl-N,N'-diphenylmalonamide (DMDΦMA) is taken as a reference. The collected spectroscopic results point out that either the presence of a central alkyl chain on N,N'-dimethyl-N,N'-diphenyl skeleton malonamides or the replacement of the N,N'-diphenyl groups by dicyclohexyl-or di-n-hexyl ones, likely determines iron(III) extraction through a solvation pathway, also involving the extraction of HCl molecules. [ABSTRACT FROM AUTHOR]

Abstract: Metalloporphyrins were isolated from copper-bearing black shale ores. The shale originates from the Lubin copper mine (Poland). The porphyrins have been extracted by way of a Soxhlet apparatus, and then purified using column chromatography. In order to identify the extracted porphyrins complexes UV–Vis, mass spectrometry and EPR analytical techniques have been used. [Copyright &y& Elsevier]

Aims To assess the antiischaemic efficacy and tolerability of the metabolic agent trimetazidine in combination with metoprolol in patients with stable effort angina.Methods This was a randomized, multicentre, double-blind, placebo-controlled parallel group study. A total of 426 male and female patients with stable, effortinduced angina and documented coronary artery disease received either placebo or trimetazidine 20mg three times daily in addition to metoprolol 50mg twice daily. Treadmill exercise tests were performed at weeks (−1), 0, 4 and 12.Results After 12 weeks, there were significantly greater improvements in the metoprolol + trimetazidine group than in the metoprolol + placebo group in: time to 1mm ST segment depression, total workload, time to onset of angina, maximum ST segment depression, mean weekly number of angina attacks, mean weekly nitrate consumption, and grade of anginal pain. There was no evidence of any development of tolerance to trimetazidine. The tolerability of trimetazidine was excellent.Conclusions Therapy with trimetazidine plus metoprolol produced significant improvements in exercise stress tests and the symptoms of angina relative to metoprolol alone. With its metabolic effect, devoid of any haemodynamic action, trimetazidine is useful for combination therapy in patients with stable angina insufficiently controlled by monotherapy with a beta-blocker. [ABSTRACT FROM PUBLISHER]

Aims To compare management and clinical outcomes in hospitals stratified by the availability of on-site catheterization in InTIME-II, a multicentre trial comparing alteplase with lanoteplase for acute myocardial infarction.Methods and Results We studied 15–078 patients enrolled in 35 countries and 855 hospitals. Thirty-one percent of hospitals had 24-h, 25% day-only, and 44% no on-site catheterization facilities. Rates of cardiac angiography (57%, 38%, 26%) and revascularization (37%, 21%, 17%) were higher in hospitals with increasing access to on-site facilities )Conclusions There is a marked variation in procedure use by the availability of on-site catheterization with no major differences in patient outcomes. There is a need for additional randomized trials in the current era to address both the appropriate selection of patients and timing of invasive procedures in ST-elevation acute myocardial infarction. [ABSTRACT FROM PUBLISHER]

Objective: Conventional anti-anginal agents may be associated with significant adverse effects in the elderly, often a direct consequence of their haemodynamic action. Trimetazidine is a metabolic agent, which acts at the myocardial mitochondrial level to exert an anti-ischaemic effect in the absence of significant haemodynamic changes. It may therefore be a particularly useful drug in the elderly. The aim of this open, multicentre study was to assess the anti-ischaemic efficacy and tolerability of trimetazidine when added to existing anti-anginal therapy in elderly patients with angina pectoris. Patients and Methods: 71 elderly patients (aged >65 years) with proven coronary artery disease and stable effort-induced angina were included. After a 1-week run-in period to ensure stability, open-label trimetazidine 20mg three times daily was administered for 4 weeks in combination with previous treatment (monotherapy with either a long-acting nitrate, β-blocker or calcium antagonist). Results: Compared with baseline, trimetazidine significantly improved exercise duration (396.5 vs 362.6 sec; p < 0.01), time to onset of anginal pain (365.4 vs 239.3 sec; p < 0.01), time to 1mm ST-segment depression (300.9 vs 250.0 sec; p < 0.01) and total work (7.49 vs 7.12 metabolic equivalents; p = 0.014) during maximal exercise testing. Maximal ST-segment depression was attenuated compared with baseline. No changes in rate-pressure product were evident at maximal exercise. Other findings included a significant reduction in the frequency of anginal episodes and weekly nitrate consumption (both p < 0.01). Conclusions: These results indicate that trimetazidine is effective and well tolerated when used in combination with existing anti-anginal therapy in elderly patients with angina pectoris. [ABSTRACT FROM AUTHOR]

Objective: To compare baseline characteristics, complications, and treatment-specific outcomes of women and men with acute myocardial infarction treated with thrombolytic therapy.Design: Randomized controlled trial.Patients and Setting: A total of 10315 women and 30706 men with acute myocardial infarction treated in 1081 hospitals in 15 countries as part of the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO-I).Intervention: One of four thrombolytic regimens: (1) streptokinase with subcutaneous heparin; (2) streptokinase with intravenous heparin; (3) streptokinase plus alteplase (tissue-type plasminogen activator) with intravenous heparin; or (4) accelerated alteplase with intravenous heparin.Main Outcome Measures: Mortality, stroke, and nonfatal complications during 30-day follow-up.Results: Women were on average 7 years older than men and delayed 18 minutes (median) longer after symptom onset before presenting to the hospital. After adjustment for age, women more often had a history of diabetes, hypertension, and smoking than men. Time to treatment was significantly longer in women (1.2 vs 1.0 hours; P<.001). Women had more nonfatal complications after treatment, including shock (9% vs 5%; P<.001), congestive heart failure (22% vs 14%; P<.001), serious bleeding (15% vs 7%; P<.001), and reinfarction (5.1% vs 3.6%; P<.001). Women had twice as many total strokes as men (2.1% vs 1.2%; P<.001), secondary to their older age at presentation. The unadjusted mortality rate was twice as high in women as men (11.3% vs 5.5%; P<.001); the relative risk (RR) of death was greater among women than men after adjustment for differences in baseline characteristics (RR=1.15; 95% confidence interval, 1.0 to 1.31). Although women and men underwent angiography at similar rates, there were small but significant differences in their rates of revascularization procedures (angioplasty: 35% of women and 32% of men; bypass surgery: 7% of women and 9% of men; P<.001 for both). The higher rate of stroke in women after treatment with alteplase (2.0% vs 1.9% with streptokinase and intravenous heparin) was offset by a greater relative reduction in mortality (10.3% vs 11.1%).Conclusion: Women who received thrombolytic therapy for treatment of acute myocardial infarction were at greater risk for both fatal and nonfatal complications than men. [ABSTRACT FROM AUTHOR]

The modelling of flow leaching solution through the porous media has been considered. The heap bioleaching process can be tested using the column experimental equipment. This equipment was employed to the hydrodynamic studies of copper ore bioleaching. The copper ore (black shale ore) with the support, inertial materials (glass small balls and polyethylene beads) was used to the bioleaching tests. The packed beds were various composition, the ore/support ratio was changed. The correlation between the bed porosity and bioleaching kinetics, and copper recovery was investigated.

The fungus-mediated synthesis of gold nanoparticles with various shapes and sizes is reported. Shape and size of the products may be controlled using different concentrations of HAuCl4. [ABSTRACT FROM AUTHOR]

The bioleaching of flotation concentrate is a new method for copper recovery that could form the basis of an economic and environmentally friendly process. The main objective of this work was to evaluate a bioleaching process from the treatment of two concentrates, (i) a copper gold bearing concentrate and (ii) an ordinary copper flotation concentrate, using mesophilic bacteria. The special gold-bearing copper flotation concentrate was obtained from the Polkowice Mine. The second material was an ordinary copper flotation concentrate purchased from the Lubin Mine. Bioleaching experiments were carried out in 250 ml Erlenmayer flasks and a rotating bioreactor (biorotor). The most important operating parameters were copper dissolution (%) and surface area. A culture of Thiobacillus ferrooxidans was used for the bioleaching tests. The bioleaching maximum was obtained at both 12% and 15% of the solid. The effect of pyrite addition on the kinetics of copper concentrate bioleaching was also investigated. It was established that 3% of pyrite causes an increase in the bioleaching process. In the case of ordinary flotation concentrate bioleaching, 65% of the recovery was obtained at the initial stage (48 h). In the second stage, the copper recovery slowly increased and after 312 h 86% of the copper recovery was obtained. On the other hand, the surface area of copper concentrate initially increased (at 24 h it was 8.67 m2/g) and then slightly decreased in the second stage. [Copyright &y& Elsevier]

The possibilities of metals recovery from copper ores with the biotechnological methods are widely known. The methods consist in bioleaching of copper ores, copper concentrates and byproducts of their production, as well as metals recovery from leaching solutions. Biohydrometallurgical methods were tested for years to be applied at KGHM Polska Miedź S.A., in order to improve efficiency of copper production. Several different research units worked on the topic, and the most significant and wide range initiatives in this area are mentioned in this article. One of the initiatives is an ongoing German and French Ecometals project. KGHM Polska Miedź S.A. and KGHM Cuprum Ltd. Research and Development Centre are this project Partners. In the frame of the project different metals bearing materials (ores, concentrates and tailings) are tested. Among them three lithological types of the copper ore from Rudna mine and the copper concentrate from Lubin concentrator are used for studies. The article gives a general overview of these activities, with the main focus on results of bioleaching studies of selected materials, conducted by KGHM Cuprum. In these studies sandstone and shale, as well as so called “shale concentrate” (containing 39% of the shale) were used for experiments, and possibilities of their bioleaching were evaluated.

Serpentinites have the potential to be used as carbo dioxide capture and storage materials. Acid dissolution is the first stage of this process. This study examined how a shrinking core model can be applied to the dissolution of serpentinite in sulphuric acid. The dissolution process was assumed to occur in two stages: an initial step involving the surface dissolution of serpentinite pieces, and a second step involving surface chemical reaction, described by the shrinking core model. The model formulation was completed by relating the dissolution rate of serpentinite to the surface changes.

Background: It is unclear whether stable, high-risk patients with persistent total occlusion of the infarct-related coronary artery identified after the currently accepted period for myocardial salvage has passed should undergo percutaneous coronary intervention (PCI) in addition to receiving optimal medical therapy to reduce the risk of subsequent events.Methods: We conducted a randomized study involving 2166 stable patients who had total occlusion of the infarct-related artery 3 to 28 days after myocardial infarction and who met a high-risk criterion (an ejection fraction of <50% or proximal occlusion). Of these patients, 1082 were assigned to routine PCI and stenting with optimal medical therapy, and 1084 were assigned to optimal medical therapy alone. The primary end point was a composite of death, myocardial reinfarction, or New York Heart Association (NYHA) class IV heart failure.Results: The 4-year cumulative primary event rate was 17.2% in the PCI group and 15.6% in the medical therapy group (hazard ratio for death, reinfarction, or heart failure in the PCI group as compared with the medical therapy group, 1.16; 95% confidence interval [CI], 0.92 to 1.45; P=0.20). Rates of myocardial reinfarction (fatal and nonfatal) were 7.0% and 5.3% in the two groups, respectively (hazard ratio, 1.36; 95% CI, 0.92 to 2.00; P=0.13). Rates of nonfatal reinfarction were 6.9% and 5.0%, respectively (hazard ratio, 1.44; 95% CI, 0.96 to 2.16; P=0.08); only six reinfarctions (0.6%) were related to assigned PCI procedures. Rates of NYHA class IV heart failure (4.4% vs. 4.5%) and death (9.1% vs. 9.4%) were similar. There was no interaction between treatment effect and any subgroup variable (age, sex, race or ethnic group, infarct-related artery, ejection fraction, diabetes, Killip class, and the time from myocardial infarction to randomization).Conclusions: PCI did not reduce the occurrence of death, reinfarction, or heart failure, and there was a trend toward excess reinfarction during 4 years of follow-up in stable patients with occlusion of the infarct-related artery 3 to 28 days after myocardial infarction. (ClinicalTrials.gov number, NCT00004562 [ClinicalTrials.gov].). [ABSTRACT FROM AUTHOR]