277 research outputs found
Protective Effects of Carvedilol and Vitamin C against Azithromycin-Induced Cardiotoxicity in Rats via Decreasing ROS, IL1- β
The Food and Drug Administration recently warned of the fatal cardiovascular risks of azithromycin in humans. In addition, a recently published study documented azithromycin-induced cardiotoxicity in rats. This study aimed to justify the exact cardiovascular events accompanying azithromycin administration in rats, focusing on electrocardiographic, biochemical, and histopathological changes. In addition, the underlying mechanisms were studied regarding reactive oxygen species production, cytokine release, and apoptotic cell-death. Finally, the supposed protective effects of both carvedilol and vitamin C were assessed. Four groups of rats were used: (1) control, (2) azithromycin, (3) azithromycin + carvedilol, and (4) azithromycin + vitamin C. Azithromycin resulted in marked atrophy of cardiac muscle fibers and electrocardiographic segment alteration. It increased the heart rate, lactate dehydrogenase, creatine phosphokinase, malondialdehyde, nitric oxide, interleukin-1 beta (IL1-β), tumor necrosis factor alpha (TNF-α), nuclear factor kappa beta (NF-κB), and caspase-3. It decreased reduced glutathione, glutathione peroxidase, and superoxide dismutase. Carvedilol and vitamin C prevented most of the azithromycin-induced electrocardiographic and histopathological changes. Carvedilol and vitamin C decreased lactate dehydrogenase, malondialdehyde, IL1-β, TNF-α, NF-κB, and caspase-3. Both agents increased glutathione peroxidase. This study shows that both carvedilol and vitamin C protect against azithromycin-induced cardiotoxicity through antioxidant, immunomodulatory, and antiapoptotic mechanisms
Thermodynamic Parameters of the Uncatalyzed Redox Reaction Between Potassium Peroxydisulphate and D(+)Glucose
The uncatalyzed redox reaction between potassium peroxydisulphate and D(+) glucose was studied titremetically . The progress of the reaction was followed by examining the concentration of potassium peroxydisulphate in the reaction mixture at different time intervals by iodometric titration method. Thermodynamic parameters, activation energy (Ea), frequency factor (A), entropy change (?S) and the free energy change (?G) of the uncatalyzed redox reaction were evaluated from the values of the fractional order rate constants ko at different temperatures. Keywords: Uncatalyzed redox reaction, thermodynamic parameters, D(+)glucose, Potassium peroxydisulphate
The effect of dividend payments and firm’s attributes on earnings quality: empirical evidence from Egypt
This empirical study aims mainly to investigate the effect of both dividend payments (DP) and five firm's attributes (firm size, firm leverage, firm performance, legal form and audit quality) on earnings quality (EQ) of the most active listed firms in Egypt. A sample of 552 firm-year observations during four years from 2014 to 2017 was used. Hierarchical Multiple Regression (HMR) was used to regress the six independent variables on firms’ EQ through the absence of firms’ earnings management (EM), which was estimated through discretionary accruals (DAC). Main results show that there is some divergence in EM practices over the four years and might suggest that EM by listed firms in Egypt exists especially in the first two years (2014 and 2015); how¬ever, relatively lower EM practices are found in the last two years (2016 and 2017). Correlation results show a number of significant relationships between the EM and three independent variables (firm leverage, legal form and audit quality). HMR results are in line with the results obtained via Pearson correlation
Nanocrystalline Na0.1V2O5.nH2Oxerogel Thin Film for Gas Sensing
Nanocrystalline thin film of Na0.1V2O5.nH2O xerogel obtained by sol-gel synthesis was used as a gas sensor. Gas sensing properties of different gases such as hydrogen, petroleum and humidity were investigated. Applying XRD and TEM the size of the nanocrystals is found to be 7.5 nm. SEM shows a highly porous structure with submicron meter-sized voids present throughout the sample. FTIR measurement shows different chemical groups identifying the obtained series of gels. The sample was n-type semiconductor according to the thermoelectric power and electrical conductivity. It can be seen that the sensor response curves from 130°C to 150°C show a rapid increase in sensitivity for all types of gas injection, low response values for heating period and the rapid high response values for cooling period. This result may suggest that this material is able to act as gas sensor during the heating and cooling process
Nanocrystalline Na0.1V2O5.nH2Oxerogel Thin Film for Gas Sensing
Nanocrystalline thin film of Na0.1V2O5.nH2O xerogel obtained by sol-gel synthesis was used as a gas sensor. Gas sensing properties of different gases such as hydrogen, petroleum and humidity were investigated. Applying XRD and TEM the size of the nanocrystals is found to be 7.5 nm. SEM shows a highly porous structure with submicron meter-sized voids present throughout the sample. FTIR measurement shows different chemical groups identifying the obtained series of gels. The sample was n-type semiconductor according to the thermoelectric power and electrical conductivity. It can be seen that the sensor response curves from 130°C to 150°C show a rapid increase in sensitivity for all types of gas injection, low response values for heating period and the rapid high response values for cooling period. This result may suggest that this material is able to act as gas sensor during the heating and cooling process
The Value Relevance of International Financial Reporting Standards (IFRS): The Case of the GCC Countries
Improvement of drought tolerance in five different cultivars of Vicia faba with foliar application of ascorbic acid or silicon
Aim of study: To explore the role of ascorbic acid (AsA) or silicon (Si) in improving drought tolerance in five faba bean cultivars under irrigation water deficit (IWD).Area of study: The experimental farm; 30° 36′ N, 32° 16′ E, Egypt.Material and methods: Three drip irrigation regimes (WW, well-watered, 4000 m3 water ha-1; MD, moderate drought, 3000 m3 water ha-1; and SD, severe drought, 2000 m3 water ha-1) were applied to plants, which were sprayed 25, 40, and 55 days after sowing with 1.5 mM AsA or 2.0 mM Si vs distilled water as a control.Main results: Drought negatively affected physiological attributes (photosynthetic pigments, gas exchange parameters, relative water content, membrane stability index, electrolyte leakage (EL), and lipid peroxidation), which restricted plant growth and yields, and stimulated alterations in both enzymatic and non-enzymatic antioxidant activities. However, AsA or Si application mitigated drought effects on physiological attributes, improving growth, yields and water use efficiency by raising antioxidant activities and suppressing lipid peroxidation and EL in stressful cultivars. The mitigating effects of AsA and Si were more pronounced under MD.Research highlights: ‘Nubaria-2’, ‘Giza-843’, and ‘Sakha-3’ were more tolerant than ‘Giza-716’ and ‘Sakha-4’, suggesting the use of AsA or Si to ameliorate the IWD effects on stressful cultivars. Certain physiological traits exhibited positive association with growth and seed yield, demonstrating their importance in enhancing seed yield under irrigation treatments
Adsorptive stripping voltammetry determination of the hormone therapy Raloxifene HCl in formulation and human serum
Integrated application of bacterial carbonate precipitation and silicon nanoparticles enhances productivity, physiological attributes, and antioxidant defenses of wheat (Triticum aestivum L.) under semi-arid conditions
The use of calcium carbonate-precipitating bacteria (CCPB) has become a well-established ground-improvement technique. However, the effect of the interaction of CCPB with nanoparticles (NPs) on plant performance is still meager. In this study, we aimed at evaluating the role of CCPB and/or silicon NPs (Si-NPs) on the growth, physio-biochemical traits, and antioxidative defense of wheat (Triticum aestivum L.) under semi-arid environmental conditions. A 2-year pot experiment was carried out to determine the improvement of the sandy soil inoculated with CCPB and the foliar application of Si-NPs on wheat plants. We tested the following treatments: spraying plants with 1.0 or 1.5 mM Si-NPs (control = 0 mM Si-NPs), soil inoculated with Bacillus lichenforms (MA16), Bacillus megaterium (MA27), or Bacillus subtilis (MA34), and the interaction of individual Bacillus species with Si-NPs. Our results showed that soil inoculation with any of the three isolated CCPB and/or foliar application of Si-NPs at the rates of 1.0 or 1.5 mM significantly improved (p ≤ 0.05) the physiological and biochemical attributes as well as the enzymatic antioxidant activities of wheat plants. Therefore, the combined treatments of CCPB + Si-NPs were more effective in enhancing physio-biochemical characteristics and enzymatic antioxidant activities than the individual treatments of CCPB or Si-NPs, thus achieving the best performance in the treatment of MA34 + 1.5 mM Si-NPs. Our results demonstrated that the co-application of CCPB and Si-NPs, particularly MA34 + 1.5 mM Si-NPs, considerably activated the antioxidant defense system to mitigate the adverse effects of oxidative stress, thus increasing tolerance and enhancing the production of wheat plants in sandy soils under semi-arid environmental conditions
Ore Genesis of the Abu Ghalaga Ferro-Ilmenite Ore Associated with Neoproterozoic Massive-Type Gabbros, South-Eastern Desert of Egypt: Evidence from Texture and Mineral Chemistry
Massif-type mafic intrusions (gabbro and anorthosite) are known for their considerable resources of vanadium-bearing iron–titanium oxide ores. Massive-type gabbroic and anorthosite rocks are frequently associated with magmatic rocks that have significant quantities of iron, titanium, and vanadium. The most promising intrusions that host Fe-Ti oxide ores are the gabbroic rocks in the south-eastern desert. The ilmenite ore deposits are hosted in arc gabbroic and anorthosite rocks. They are classified into three types, namely black ore, red ore, and disseminated ore. The black ilmenite ore is located at the deeper level, while the oxidized red ore is mainly located at or near the surface. Petrographically, the gabbro and ilmenite ores indicate a crystallization sequence of plagioclase, titaniferous pyroxene, and ilmenite. This reveals that the ilmenite is a magmatic deposit formed by the liquid gravity concentration of ilmenite following the crystallization of feldspar and pyroxene. Meanwhile, quartz, tremolite, zoisite, and opaque minerals are accessory minerals. The Fe-Ti ores are composed of ilmenite hosting exsolved hematite lamellae of variable sizes and shapes, gangue silicate minerals, and some sulfides. The X-ray diffraction (XRD) data reveal the presence of two mineral phases: ilmenite and hematite formed by the unmixing of the ferroilmenite homogeneous phase upon cooling. As a result, the ore is mostly made up of hemo-ilmenite. Using an electron microscope (SEM), as well as by observing the textures seen by the ore microscope, ilmenite is the dominant Fe-Ti oxide and contains voluminous hematite exsolved crystals. Under the scanning electron microscope, ilmenite contained intergrowths of hematite as a thin sandwich and lens shape. The formation of hematite lamellae indicates an oxidation process. Mineral chemistry-based investigations reveal late/post-magmatic activity at high temperatures. The examined ilmenite plots on the ferro-ilmenite line were created by continuous solid solution over 800 °C, whereas the analyzed magnetite and Ti-magnetite plot near the magnetite line and were formed by continuous solid solution exceeding 600 °C
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