The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Bramah N Singh - One of the best experts on this subject based on the ideXlab platform.
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effects of amiodarone sematilide and sotalol on qt Dispersion
American Journal of Cardiology, 1994Co-Authors: Guanggen Cui, Luyi Sen, Philip T Sager, Parveen Uppal, Bramah N SinghAbstract:To study the effects of class III agents on QT/QTc Dispersion in patients with heart disease and cardiac arrhythmias, QT Dispersion and QRS and RR intervals were compared in patients before and after treatment with amiodarone (n = 26), sematilide (n = 26), and sotatol (n = 26). QT, QRS, and RR intervals, and QTc values were calculated for each complex, and their mean values were calculated for each lead. QT and QTc Dispersions were defined as differences between the minimal and maximal QT or QTc values in each of the 12 leads studied. Amiodarone, sematilide, and sotalol all significantly prolonged the QT interval and the QTc value. Significant reductions in QT and QTc Dispersions were only found in the amiodarone group (QT Dispersions: 79 ± 13 vs 49 ± 14 ms; p 0.2). The baseline QT and QTc Dispersions were significantly greater in patients with than without myocardial infarction before treatment (p < 0.001). The mean baseline values for QT/QTc Dispersions were not significantly different among all 3 groups. However, only amiodarone significantly reduced the QT Dispersion (from 76 ± 10 to 46 ± 11 ms; p < 0.001) and QTc Dispersion (from 0.09 ± 0.02 to 0.05 ± 0.01 s12; p < 0.001) in patients with myocardial infarction. The reduction in the QT/QTc Dispersion was significantly greater than that in patients without myocardial infarction (p < 0.01). It is concluded that (1) antiarrhythmic agents that act by lengthening repolarization have differing effects on QT/QTc Dispersion, most likely reflecting differences in their fundamental mechanisms whereby they prolong myocardial repolarization, and (2) the low reported incidence of torsades de pointes with amiodarone may in part be due to reduced Dispersion of QT and QTc compared with other class III agents.
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effects of amiodarone sematilide and sotalol on qt Dispersion
American Journal of Cardiology, 1994Co-Authors: Guanggen Cui, Luyi Sen, Philip T Sager, Parveen Uppal, Bramah N SinghAbstract:To study the effects of class III agents on QT/QTc Dispersion in patients with heart disease and cardiac arrhythmias, QT Dispersion and QRS and RR intervals were compared in patients before and after treatment with amiodarone (n = 26), sematilide (n = 26), and sotalol (n = 26). QT, QRS, and RR intervals, and QTc values were calculated for each complex, and their mean values were calculated for each lead. QT and QTc Dispersions were defined as differences between the minimal and maximal QT or QTc values in each of the 12 leads studied. Amiodarone, sematilide, and sotalol all significantly prolonged the QT interval and the QTc value. Significant reductions in QT and QTc Dispersions were only found in the amiodarone group (QT Dispersions: 79 +/- 13 vs 49 +/- 14 ms; p 0.2). The baseline QT and QTc Dispersions were significantly greater in patients with than without myocardial infarction before treatment (p < 0.001). The mean baseline values for QT/QTc Dispersions were not significantly different among all 3 groups. However, only amiodarone significantly reduced the QT Dispersion (from 76 +/- 10 to 46 +/- 11 ms; p < 0.001) and QTc Dispersion (from 0.09 +/- 0.02 to 0.05 +/- 0.01 s1/2; p < 0.001) in patients with myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)
Ali Nokhodchi - One of the best experts on this subject based on the ideXlab platform.
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The dissolution enhancement of piroxicam in its physical mixtures and solid Dispersion formulations using gluconolactone and glucosamine hydrochloride as potential carriers
Pharmaceutical development and technology, 2014Co-Authors: Hiba Al-hamidi, Wasfy M. Obeidat, Ali NokhodchiAbstract:The solid Dispersion technique is one of the most effective methods for improving the dissolution rate of poorly water-soluble drugs; however this is reliant on a suitable carrier and solvent being selected. The work presented explores amino sugars (d-glucosamine HCl and d-gluconolactone) as potential hydrophilic carriers to improve dissolution rate of a poorly water-soluble drug, piroxicam, from physical mixtures and solid Dispersion formulations. Solid Dispersions of the drug and carrier were prepared using different ratios by the conventional solvent evaporation method. Acetone was used as solvent in the preparation of solid Dispersions. Physical mixtures of piroxicam and carrier were also prepared for comparison. The properties of all solid Dispersions and physical mixtures were studied using a dissolution tester, Fourier transform infrared, XRD, SEM and differential scanning calorimetry. These results showed that the presence of glucosamine or gluconolactone can increase dissolution rate of piroxicam compared to pure piroxicam. Glucosamine or Gluconolactone could be used as carrier in solid Dispersion formulations and physical mixtures to enhance the dissolution rate. Solid state studies showed that no significant changes occurred for piroxicam in physical mixtures and solid Dispersion.
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to enhance dissolution rate of poorly water soluble drugs glucosamine hydrochloride as a potential carrier in solid Dispersion formulations
Colloids and Surfaces B: Biointerfaces, 2010Co-Authors: Hiba Alhamidi, Ali Nokhodchi, Alison A Edwards, Mohammad Amin MohammadAbstract:The solid Dispersion technique is the most effective method for improving the dissolution rate of poorly water-soluble drugs, however this is reliant on a suitable carrier and solvent being selected. The work presented explores d-glucosamine HCl (G-HCl) as a potential hydrophilic carrier to improve dissolution rate of a poorly water-soluble drug, carbamazepine (CBZ), from physical mixtures and solid Dispersion formulations. The effect of different solvents in the preparation of solid Dispersion formulations was also investigated. Solid Dispersions of the drug and G-HCl were prepared using different ratios by the conventional solvent evaporation method. Different solvents (ethanol, acetone and water) were used as second variable in the preparation of solid Dispersions. Physical mixtures of CBZ and G-HCl were also prepared for comparison. The properties of all solid Dispersions and physical mixtures were studied using a dissolution tester, FT-IR, SEM and DSC. These results showed that the presence of glucosamine can increase dissolution rate of CBZ compared to pure CBZ. All solid Dispersions of CBZ-G-HCl showed considerably a higher dissolution rate than the corresponding physical mixtures. The presence of water during preparation of the solid Dispersions reduced the dissolution rate of CBZ due to formation of carbamazepine dihydrate during the preparation of solid Dispersion, as proved by DSC and FT-IR studies. To facilitate comparison, the dissolution efficiency was calculated for solid Dispersions prepared with different solvents and the dissolution efficiency can generally be ranked as follows: ethanol > acetone > ethanol-water > acetone-water when the ratios of drug to carrier were 4:1 and 2:1. It has thus been shown that the use of G-HCl in solid Dispersion formulations can significantly enhance the dissolution rate of poorly water-soluble drugs such as carbamazepine. This amino sugar could be used as a new carrier in solid Dispersion formulations and would have significant commercial potential. © 2009 Elsevier B.V. All rights reserved.
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preparation and characterization of solid Dispersions of piroxicam with hydrophilic carriers
Drug Development and Industrial Pharmacy, 2007Co-Authors: Hadi Valizadeh, Parvin Zakerimilani, Mohammad Barzegarjalali, Ghobad Mohammadi, Mohammadali Daneshbahreini, Khosro Adibkia, Ali NokhodchiAbstract:The objective of this study was to improve the dissolution rate of a poor water soluble drug, piroxicam, by solid Dispersion technique. Solid Dispersions were prepared by three different methods depending on the type of carrier. The dissolution rate of piroxicam was markedly increased in solid Dispersion of myrj 52, Eudragit® E100 and mannitol. Solubility studies revealed a marked increase in the solubility of piroxicam with an increase in myrj 52 and Eudragit® E100 concentrations. Data from the X-ray diffraction and FT-IR spectroscopy showed that piroxicam was amorphous in the solid Dispersions prepared with dextrin and Eudragit® E100.
Guanggen Cui - One of the best experts on this subject based on the ideXlab platform.
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effects of amiodarone sematilide and sotalol on qt Dispersion
American Journal of Cardiology, 1994Co-Authors: Guanggen Cui, Luyi Sen, Philip T Sager, Parveen Uppal, Bramah N SinghAbstract:To study the effects of class III agents on QT/QTc Dispersion in patients with heart disease and cardiac arrhythmias, QT Dispersion and QRS and RR intervals were compared in patients before and after treatment with amiodarone (n = 26), sematilide (n = 26), and sotatol (n = 26). QT, QRS, and RR intervals, and QTc values were calculated for each complex, and their mean values were calculated for each lead. QT and QTc Dispersions were defined as differences between the minimal and maximal QT or QTc values in each of the 12 leads studied. Amiodarone, sematilide, and sotalol all significantly prolonged the QT interval and the QTc value. Significant reductions in QT and QTc Dispersions were only found in the amiodarone group (QT Dispersions: 79 ± 13 vs 49 ± 14 ms; p 0.2). The baseline QT and QTc Dispersions were significantly greater in patients with than without myocardial infarction before treatment (p < 0.001). The mean baseline values for QT/QTc Dispersions were not significantly different among all 3 groups. However, only amiodarone significantly reduced the QT Dispersion (from 76 ± 10 to 46 ± 11 ms; p < 0.001) and QTc Dispersion (from 0.09 ± 0.02 to 0.05 ± 0.01 s12; p < 0.001) in patients with myocardial infarction. The reduction in the QT/QTc Dispersion was significantly greater than that in patients without myocardial infarction (p < 0.01). It is concluded that (1) antiarrhythmic agents that act by lengthening repolarization have differing effects on QT/QTc Dispersion, most likely reflecting differences in their fundamental mechanisms whereby they prolong myocardial repolarization, and (2) the low reported incidence of torsades de pointes with amiodarone may in part be due to reduced Dispersion of QT and QTc compared with other class III agents.
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effects of amiodarone sematilide and sotalol on qt Dispersion
American Journal of Cardiology, 1994Co-Authors: Guanggen Cui, Luyi Sen, Philip T Sager, Parveen Uppal, Bramah N SinghAbstract:To study the effects of class III agents on QT/QTc Dispersion in patients with heart disease and cardiac arrhythmias, QT Dispersion and QRS and RR intervals were compared in patients before and after treatment with amiodarone (n = 26), sematilide (n = 26), and sotalol (n = 26). QT, QRS, and RR intervals, and QTc values were calculated for each complex, and their mean values were calculated for each lead. QT and QTc Dispersions were defined as differences between the minimal and maximal QT or QTc values in each of the 12 leads studied. Amiodarone, sematilide, and sotalol all significantly prolonged the QT interval and the QTc value. Significant reductions in QT and QTc Dispersions were only found in the amiodarone group (QT Dispersions: 79 +/- 13 vs 49 +/- 14 ms; p 0.2). The baseline QT and QTc Dispersions were significantly greater in patients with than without myocardial infarction before treatment (p < 0.001). The mean baseline values for QT/QTc Dispersions were not significantly different among all 3 groups. However, only amiodarone significantly reduced the QT Dispersion (from 76 +/- 10 to 46 +/- 11 ms; p < 0.001) and QTc Dispersion (from 0.09 +/- 0.02 to 0.05 +/- 0.01 s1/2; p < 0.001) in patients with myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)
Parveen Uppal - One of the best experts on this subject based on the ideXlab platform.
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effects of amiodarone sematilide and sotalol on qt Dispersion
American Journal of Cardiology, 1994Co-Authors: Guanggen Cui, Luyi Sen, Philip T Sager, Parveen Uppal, Bramah N SinghAbstract:To study the effects of class III agents on QT/QTc Dispersion in patients with heart disease and cardiac arrhythmias, QT Dispersion and QRS and RR intervals were compared in patients before and after treatment with amiodarone (n = 26), sematilide (n = 26), and sotatol (n = 26). QT, QRS, and RR intervals, and QTc values were calculated for each complex, and their mean values were calculated for each lead. QT and QTc Dispersions were defined as differences between the minimal and maximal QT or QTc values in each of the 12 leads studied. Amiodarone, sematilide, and sotalol all significantly prolonged the QT interval and the QTc value. Significant reductions in QT and QTc Dispersions were only found in the amiodarone group (QT Dispersions: 79 ± 13 vs 49 ± 14 ms; p 0.2). The baseline QT and QTc Dispersions were significantly greater in patients with than without myocardial infarction before treatment (p < 0.001). The mean baseline values for QT/QTc Dispersions were not significantly different among all 3 groups. However, only amiodarone significantly reduced the QT Dispersion (from 76 ± 10 to 46 ± 11 ms; p < 0.001) and QTc Dispersion (from 0.09 ± 0.02 to 0.05 ± 0.01 s12; p < 0.001) in patients with myocardial infarction. The reduction in the QT/QTc Dispersion was significantly greater than that in patients without myocardial infarction (p < 0.01). It is concluded that (1) antiarrhythmic agents that act by lengthening repolarization have differing effects on QT/QTc Dispersion, most likely reflecting differences in their fundamental mechanisms whereby they prolong myocardial repolarization, and (2) the low reported incidence of torsades de pointes with amiodarone may in part be due to reduced Dispersion of QT and QTc compared with other class III agents.
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effects of amiodarone sematilide and sotalol on qt Dispersion
American Journal of Cardiology, 1994Co-Authors: Guanggen Cui, Luyi Sen, Philip T Sager, Parveen Uppal, Bramah N SinghAbstract:To study the effects of class III agents on QT/QTc Dispersion in patients with heart disease and cardiac arrhythmias, QT Dispersion and QRS and RR intervals were compared in patients before and after treatment with amiodarone (n = 26), sematilide (n = 26), and sotalol (n = 26). QT, QRS, and RR intervals, and QTc values were calculated for each complex, and their mean values were calculated for each lead. QT and QTc Dispersions were defined as differences between the minimal and maximal QT or QTc values in each of the 12 leads studied. Amiodarone, sematilide, and sotalol all significantly prolonged the QT interval and the QTc value. Significant reductions in QT and QTc Dispersions were only found in the amiodarone group (QT Dispersions: 79 +/- 13 vs 49 +/- 14 ms; p 0.2). The baseline QT and QTc Dispersions were significantly greater in patients with than without myocardial infarction before treatment (p < 0.001). The mean baseline values for QT/QTc Dispersions were not significantly different among all 3 groups. However, only amiodarone significantly reduced the QT Dispersion (from 76 +/- 10 to 46 +/- 11 ms; p < 0.001) and QTc Dispersion (from 0.09 +/- 0.02 to 0.05 +/- 0.01 s1/2; p < 0.001) in patients with myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)
Philip T Sager - One of the best experts on this subject based on the ideXlab platform.
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effects of amiodarone sematilide and sotalol on qt Dispersion
American Journal of Cardiology, 1994Co-Authors: Guanggen Cui, Luyi Sen, Philip T Sager, Parveen Uppal, Bramah N SinghAbstract:To study the effects of class III agents on QT/QTc Dispersion in patients with heart disease and cardiac arrhythmias, QT Dispersion and QRS and RR intervals were compared in patients before and after treatment with amiodarone (n = 26), sematilide (n = 26), and sotatol (n = 26). QT, QRS, and RR intervals, and QTc values were calculated for each complex, and their mean values were calculated for each lead. QT and QTc Dispersions were defined as differences between the minimal and maximal QT or QTc values in each of the 12 leads studied. Amiodarone, sematilide, and sotalol all significantly prolonged the QT interval and the QTc value. Significant reductions in QT and QTc Dispersions were only found in the amiodarone group (QT Dispersions: 79 ± 13 vs 49 ± 14 ms; p 0.2). The baseline QT and QTc Dispersions were significantly greater in patients with than without myocardial infarction before treatment (p < 0.001). The mean baseline values for QT/QTc Dispersions were not significantly different among all 3 groups. However, only amiodarone significantly reduced the QT Dispersion (from 76 ± 10 to 46 ± 11 ms; p < 0.001) and QTc Dispersion (from 0.09 ± 0.02 to 0.05 ± 0.01 s12; p < 0.001) in patients with myocardial infarction. The reduction in the QT/QTc Dispersion was significantly greater than that in patients without myocardial infarction (p < 0.01). It is concluded that (1) antiarrhythmic agents that act by lengthening repolarization have differing effects on QT/QTc Dispersion, most likely reflecting differences in their fundamental mechanisms whereby they prolong myocardial repolarization, and (2) the low reported incidence of torsades de pointes with amiodarone may in part be due to reduced Dispersion of QT and QTc compared with other class III agents.
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effects of amiodarone sematilide and sotalol on qt Dispersion
American Journal of Cardiology, 1994Co-Authors: Guanggen Cui, Luyi Sen, Philip T Sager, Parveen Uppal, Bramah N SinghAbstract:To study the effects of class III agents on QT/QTc Dispersion in patients with heart disease and cardiac arrhythmias, QT Dispersion and QRS and RR intervals were compared in patients before and after treatment with amiodarone (n = 26), sematilide (n = 26), and sotalol (n = 26). QT, QRS, and RR intervals, and QTc values were calculated for each complex, and their mean values were calculated for each lead. QT and QTc Dispersions were defined as differences between the minimal and maximal QT or QTc values in each of the 12 leads studied. Amiodarone, sematilide, and sotalol all significantly prolonged the QT interval and the QTc value. Significant reductions in QT and QTc Dispersions were only found in the amiodarone group (QT Dispersions: 79 +/- 13 vs 49 +/- 14 ms; p 0.2). The baseline QT and QTc Dispersions were significantly greater in patients with than without myocardial infarction before treatment (p < 0.001). The mean baseline values for QT/QTc Dispersions were not significantly different among all 3 groups. However, only amiodarone significantly reduced the QT Dispersion (from 76 +/- 10 to 46 +/- 11 ms; p < 0.001) and QTc Dispersion (from 0.09 +/- 0.02 to 0.05 +/- 0.01 s1/2; p < 0.001) in patients with myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)
