Geochemical and electrical characterization of heavy metals in contaminated soils.

The present work is conducted in the industrial district south of greater Cairo (ElTabbin area). Some heavy metals like Mn, Co, Ni, Cu, Zn, Pb, Cr, Ba, Cd, Mo were determined in polluted soils during May, 2018. At the study area, results displayed that average heavy metals concentrations differ considerably. They are decreased from Mn to Cd (Mn > Ba > Zn > Cr > Ni > Co > Pb > Cu > Mo > Cd). The average ranges as follows: Mn (255.8-31448.2 ppm); Ba (145.2-17545.6 ppm); Zn (53.3-1589.9 ppm); Cr (26.7-311.3 ppm); Ni (29.7-114.1 ppm); Co (13.2-39.8 ppm); Pb (5.7-77.4 ppm); Cu (7.6-35.2 ppm); Mo (0.1-15.9 ppm) and Cd (0-1.5 ppm), respectively. ElTabbin area has heavy manufacturing activity at Egypt. ElTabbin area was chosen as a model for that contamination. Electrical characteristics of some specimens from El- Tebbin area, Egypt, were taken and measured electrically at frequency range (10-3 to 100 kHz). Major and heavy elements were measured at specimens. Specimens were classified to three categories according to electrical properties. The changes were the consequence of change in minor and major mineral composition in the specimens. Electrical properties were able to recognize different specimens according to different levels of contaminants in the specimens. Texture, tortuosity and minor elements of heavy elements are the controlling factors that control electrical properties at specimens. High values concentration of Mn, Ni, and Zn heavy elements increases conductivity while the high concentration of Pb and Cu heavy elements decreases the conductivity. The mixing up of these different minor and major minerals and elements at specimen may lead to the change of conductivity values. The main controlling factors of the major elements are the Fe2O3 and SiO2, while the main controlling factors of the minor elements are the Mn and Pb. Our main objective is to study mixing up of the different minor and major minerals and elements on electrical properties of rocks.

Effect of CaO/SiO2 molar ratio on the electrical and physical properties of basaltic glass materials.

The effect of CaO∖SiO2 molar ratio on the electrical properties of some glass materials was examined, using the impedance spectroscopy, at different frequency ranges, from 100 Hz up to 5 MHz. Also, a trial was accomplished to study the influence of CaO∖SiO2 molar ratio on some physical properties such as density, micro-hardness and bending strength. Six glass batches, based on Sinai basaltic rocks and bypass cement dust, were prepared with different CaO/SiO2 molar ratios (0.2-0.93 mol %). Accordingly, the electrical properties (conductivity dielectric constant and dielectric loss) of these samples show noticeable change. Electrical results show that the samples with relatively low (CaO/SiO2) molar ratio have relatively higher electrical conductivity, compared to the other samples with higher (CaO/SiO2) molar ratios, at different frequencies. Also, at the same time, the bending strength and Vickers micro-hardness show a gradual increase from 56 to 118 MPa and from 4020 to 6120 MPa, respectively, with decreasing CaO/SiO2 molar ratio. The density of the samples shows a successive increase from 2.79 to 2.96 gm/cm3 with the successive additions of bypass cement dust.

Clinical and biochemical predictors affect the choice and the short-term outcomes of different thrombolytic agents in acute myocardial infarction.

BACKGROUND: The presence of plasminogen activator inhibitor-1, angiotensin-converting enzyme and others may play a role in unsuccessful recanalization after thrombolytic therapy. OBJECTIVES: To find out the clinical and biochemical predictors that may affect the choice and short-term outcomes following different thrombolytic agents in acute myocardial infarction. METHODOLOGY: Angiotensin-converting enzyme and plasminogen activator inhibitor-1 plasma levels of 184 patients with acute myocardial infarction, treated with streptokinase, metalyze or reteplase, were determined. Failure of thrombolysis was assessed by noninvasive reperfusion criteria. Prolonged hospitalization, impaired left ventricular ejection fraction and reinfarction were considered as short-term outcomes. RESULTS: Patients who received streptokinase developed higher incidence of >50% resolution of ST-segment elevation (82.5 vs. 64.7%, P-value<0.05, in comparison with metalyze and 82.5 vs. 55.7%, P-value 0.001, in comparison with reteplase) than those who received other thrombolytic agents. High plasma angiotensin-converting enzyme was associated with prolonged hospitalization (55, 63 and 94%, P<0.02) following streptokinase, metalyze and reteplase, respectively. High plasma plasminogen activator inhibitor-1 is associated with impaired left ventricular ejection fraction (55.3, 76.7 and 68.5%, P<0.09), ST resolution<50% (13.2, 36.7 and 37.5%, P=0.03), ST resolution>50% (86.8, 63.3 and 62.5%, P=0.03) following streptokinase, metalyze and reteplase, respectively. CONCLUSIONS: Rapid determination of pretreatment angiotensin-converting enzyme and plasminogen activator inhibitor-1 plasma levels in patients with acute myocardial infarction may influence the choice and outcomes of the thrombolytic agents. The presence of a high plasma level of either angiotensin-converting enzyme or plasminogen activator inhibitor-1 is significantly associated with adverse short-term outcomes after treatment with reteplase or metalyze.

The effect of high plasma levels of angiotensin-converting enzyme (ACE) and plasminogen activator inhibitor (PAI-1) on the reperfusion after thrombolytic therapy in patients presented with acute myocardial infarction.

UNLABELLED: The resistance to thrombolytic agents and delays in reperfusion occur in more than 30% after acute myocardial infarction. This may play an important role in the unsuccessful recanalization after thrombolytic therapy. The aim of this study is to assess the clinical and biochemical markers of reperfusion after different types of thrombolytic therapy and to find out the relationship between PAI-1 and ACE serum levels and the short-term outcome. Pretreatment ACE and PAI-1 plasma levels of 184 patients with acute myocardial infarction, treated with thrombolytic therapy were determined. Failure of thrombolysis was considered when reperfusion was delayed as assessed by noninvasive reperfusion criteria, reinfarction, and impaired left ventricular function. High plasma level of ACE (> 50 U/L), PAI-1 (> 43 ng/ml) and both was found in 57, 108 and 32 patients respectively. Subjects with high ACE plasma levels were characterized by impaired LV systolic function (79.0% vs. 75.0%), new Q-wave (88.4% vs. 74.2%), less reperfusion arrhythmia (19.3% vs. 22.8%) and prolonged hospitalization (70% vs. 66%) but no statistical significance was observed. High enzymes levels of PAI-1 were observed with higher incidence of anterior myocardial infarction (50.0% vs. 41.0%), lesser ST segment resolution (65.6% vs. 58.8%), reinfarction (6.3% vs. 5.9%), and impaired LV systolic function (90.6% vs. 76.0%), and prolonged hospitalization (70.4% vs. 63.4). There was a statistically significant difference between thrombolytic agents in the presence of high ACE regarding hospital overstay (p = 0.02). While the presence of high PAI-1 was significantly affect the degree of ST-segment resolution (p = 0.03). CONCLUSION: High plasma ACE and/or PAI-1 plays a considerable role in the higher incidence of unsuccessful reperfusion and impaired left ventricular function after thrombolytic therapy. A rapid diagnostic tool that enables physician of detecting those enzymes before giving thrombolytic therapy may change the strategy of treatment to offer another effective revascularization method.