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Increases in extracellular potassium (K + ) concentration (up to 20 mM) cause dilation in some blood vessels. This may be particularly important in myocardial ischemia because in this condition K + is released from ischemic cells. In this study, we investigated mechanisms of effect of increased K + concentration on the tone of isolated bovine coronary artery. Bovine coronary arteries were isolated and mounted in organ baths for isometric tension recording. After an equilibration period, arteries were contracted with serotonin (1 μM). When serotonin contraction reached a steady-state, K + concentration of organ baths was increased from physiological levels to 10 mM, 14 mM, 18 mM or 22 mM in four groups of the arteries. After a washout period, this procedure was repeated in presence of ouabain, a blocker of Na + /K + ATPase or a K + channel blocker (tetraethylammonium, 4-aminopyridine, glibenclamide or barium). Increasing K + concentration of the organ baths to 10 mM, 14 mM and 18 mM caused dilation in the arteries. Ouabain abolished the dilation and barium (a blocker of inward rectifier K + channels) inhibited the dilation significantly.According to our results there is K + -induced dilation in bovine coronary artery and it involves activation of both Na + /K + ATPase and inward rectifier K + channels.

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Growing research on beans suggest that they are good for health, as they reduce the risk and/or help in the management of chronic diseases. Beans are valuable parts of several dietary recommendations. Saponins, α-galactosides, phytates, and lectins are currently drawing attention because of their diverse properties, both adverse and beneficial. The aim was to determine the hepatotoxic effect of dry red kidney beans, i.e. Phaseolus vulgaris, on rabbits at 4 g kg–1, 6 g kg–1, and 8 g kg–1 dosing for the period of 30 days. The histopathological examination revealed inflammation of hepatocyte at all three doses along with congestion. The biochemical testing of liver enzymes revealed elevated alanine transaminase (ALT), aspartate transaminase (AST) and gamma-glutamyl transferase (γ-GT). The dose-dependent increase in liver enzymes indicates the hepatotoxic effect of dry red kidney beans, and various studies have demonstrated that lectins are the toxic components responsible for inflammation of body organs.

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Abstract  

Reproducible specific heat capacities (C p) of triglycerides can be obtained by using heat-flux DSC under improved operating conditions. The improved operating parameters, such as the scanning rate, the sample mass and the atmosphere within the DSC chamber, were established via statistical analysis of the experimental data with trilaurin as a sample. The specific heat capacity results on trilaurin were compared with the values calculated by using estimation methods. The precision of the specific heat capacity measured for trilaurin under these conditions was within ±1%.

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Abstract  

The specific heat capacities of some triglycerides commonly found in palm oil were determined with a heat-flux differential scanning calorimeter. The specific heat capacity measurements were made under the optimum operating conditions determined earlier: scan rate 17 deg·min−1, sample mass 21 mg and purge gas (nitrogen) flow rate 50 ml/min. Pure triglycerides (four simple and four mixed) were used in the experiments. The four simple triglycerides were trilaurin, trimyristin, tripalmitin and tristearin, and the mixed triglycerides were 1,2-dimyristoyl-3-oleoyl, 1,2-dimyristoyl-3-palmitoyl, 1,2-dipalmitoyl-3-oleoyl and 1,2-dioleoyl-3-palmitoyl. The results of this study are compared with literature values and also with values obtained by using estimation methods. The experimental specific heat capacities are within ±1% precision with a 95% confidence level.

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Abstract  

The extractive properties of tri-isoamyl-phosphate (TAP), an indigenously prepared extractant, and the loading capacity of extraction solvent containing TAP for U(VI) and Pu(IV) ions in nitric solution have been investigated. The dependence of the distribution ratio on the concentration of nitric acid showed that TAP has an ability to extract these actinides, while the fission product contaminants are poorly extracted. The distribution data revealed a quantitative extraction of both U(VI) and Pu(IV) from moderate nitric acidities in the range 2–7 mol · dm–3. Slope analysis proved predominant formation of the disolvated organic phase complex of the type UO2(NO3). 2TAP and Pu(NO3)4·2TAP with U(VI) and PU(IV), respectively. On the contrary, the extraction of fission product contaminants such as144Ce,137Cs,9Nb.,147Pr,106Ru,95Zr was almost negligible even at very high nitric acid concentrations in the aqueous phase indicating its potential application in actinide partitioning. The recovery of TAP from the loaded actinides could be easily accomplished by using a dilute sodium carbonate solution or acidified distiled water (0.01 mol · dm–3 HNO3) as the strippant for U(VI) and using uranous nitrate or ferrous sulphamate as that for Pu(IV). Radiation stability of TAP was adequate for most of the process applications.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: R. C. Moore, M. Gasser, N. Awwad, K. C. Holt, F. M. Salas, A. Hasan, M. A. Hasan, H. Zhao and C. A. Sanchez

Summary  

The MARC-VI conference served as an excellent setting for a session organized to present and discuss the problems in nuclear science manpower and education. A panel discussion and contributed papers reflected the world-wide situation. This paper presents the major points of the panel discussion. As a result, a resolution on the current situation of nuclear chemistry and radiochemistry was drafted and endorsed by the conference attendees.

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Abstract  

Nano-particle, pure and CuOx-modified, fluorite-structured cubic-CeO2 were successfully synthesized with surface areas near 240 m2/g applying a microemulsion method with mixed templating surfactants (viz. DDAB and Brij®35). Following calcination at 400–800 °C, the products were characterized by X-ray powder diffractometry, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy, and, then, tested as catalysts for methylbutynol decomposition and CO oxidation in the gas phase. Results obtained showed the pure and CuOx-modified cerias to exhibit comparable activities towards the alcohol decomposition into acetone and acetylene, but the modified ceria exhibited considerably higher activity towards the CO oxidation than the pure one. The calcination product of CuOx-modified ceria at 800 °C was capable of lowering the light-off temperature of the CO oxidation from 300 °C (on the pure) down to 70 °C. Surface chemical consequences of the CuOx-modification, viz. increasing the Ce(III)/Ce(IV) atomic ratio, as well as the establishment of Cu(I) and Cu(II) sites, have been allocated the responsibility of the observed upsurge of the CO oxidation activity.

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Abstract

Objectives: Database review to analyse age and sex differences in complication and conversion rates and influence on return to normal daily activities and work after laparoscopic cholecystectomy (LC). Methods: 658 patients had a laparoscopic cholecystectomy for proven gallstones between 9/4/2001 and 15/2/2006 under the care of one surgeon (F. H.) at Benenden hospital, Kent, UK. Results: We had a 65.5% response rate with 431 replies at a mean follow up of 22.4 months (2.3–52.8). There was a male to female ratio of 5:23 with a mean age of 54.2 years (22–83). Using linear regression we found no significant correlation with operative time and variables of age and sex (df = 2, 251, R 2 = 0.03, F = 0.574, p < 0.564). No significant correlation with number of complications and age or sex (df = 2, 334, R 2 = 0.004, F = 1.615, p < 0.200). Age (Exp(B) = 1.040, p < 0.51) and sex (Exp(B) = 0.863, p < 0.855) had no effect on conversion. No difference was found in relation to age and sex with return to normal daily activities (df = 2, 307, F = 0.904, p < 0.406). Age was a non-significant predictor of return to work (Beta = 0.040, p < 0.572) however men return to work significantly sooner (Beta = 0.191, p < 0.007). Conclusions: Operative time, number of complications, conversion to open and return to normal daily activities may not be affected by age or sex of patients. Hospital stay may be longer in older patients. Men appear to return to work sooner. Further analysis with validated questionnaires are required.

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