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Port Sudan, Sudan

Reece S.E.,University of Edinburgh | Ali E.,Sudan Atomic Energy Commission | Ali E.,University of Khartoum | Schneider P.,University of Edinburgh | And 2 more authors.
Proceedings of the Royal Society B: Biological Sciences | Year: 2010

Life-history theory predicts that sexually reproducing organisms have evolved to resolve resourceallocation trade-offs between growth/survival versus reproduction, and current versus future reproduction. Malaria parasites replicate asexually in their vertebrate hosts, but must reproduce sexually to infect vectors and be transmitted to new hosts. As different specialized stages are required for these functions, the division of resources between these life-history components is a fundamental evolutionary problem. Here, we test how drug-sensitive and drug-resistant isolates of the human malaria parasite Plasmodium falciparum resolve the trade-off between in-host replication and between-host transmission when exposed to treatment with anti-malarial drugs. Previous studies have shown that parasites increase their investment in sexual stages when exposed to stressful conditions, such as drugs. However, we demonstrate that sensitive parasites facultatively decrease their investment in sexual stages when exposed to drugs. In contrast to previous studies, we tested parasites from a region where treatment with antimalarial drugs is common and transmission is seasonal. We hypothesize that when exposed to drugs, parasites invest in their survival and future transmission by diverting resources from reproduction to replication. Furthermore, as drug-resistant parasites did not adjust their investment when exposed to drugs, we suggest that parasites respond to changes in their proliferation (state) rather the presence of drugs. © 2010 The Royal Society. Source

Medani A.M.M.H.,Sudan Atomic Energy Commission | Elnour A.A.,University of Dammam | Saeed A.M.,University of Khartoum
Bulletin of the World Health Organization | Year: 2011

Objective To describe the status of iodine deficiency disorders (IDDs) in the Sudan more than 25 years after the initiation of IDD control programmes and to explore the causes of endemic goitre in the country. Methods Testing for IDDs was carried out in 6083 schoolchildren 6 to 12 years of age from the capital cities of nine states in different areas of the country using the three indicators recommended by the World Health Organization: the prevalence of goitre, laboratory measurements of urinary iodine concentration in casual urine samples and serum thyroglobulin (Tg) levels. Serum levels of thyroxine (T4), triiodothyronine (T3) and thyroid-stimulating hormone (TSH), as well as urinary secretion of thiocyanate, which can affect the transport of iodine into thyrocytes, were also measured. Findings The prevalence of goitre in the different samples ranged from 12.2% to 77.7% and was 38.8% overall. The overall median urinary iodine concentration was 6.55 μg/dl, with the lowest median value having been found in Kosti city (2.7 μg/dl), situated in the centre of the country, and the highest (46.4 μg/dl) in Port Sudan, on the Red Sea coast. The highest mean serum Tg level (66.98 ng/ml) was found in Kosti city, which also had the highest prevalence of goitre. Conclusion IDDs still constitute a public health problem throughout urban areas in the Sudan and iodine deficiency appears to be the main etiological factor involved. Source

Adam A.A.,Taif University | Eltayeb M.A.H.,Sudan Atomic Energy Commission | Ibrahim O.B.,Taif University
Arabian Journal of Chemistry | Year: 2014

This study was carried out in a laboratory scale to recover uranium from Uro area phosphate ore in the eastern part of Nuba Mountains in Sudan. Phosphate ore samples were collected, and analyzed for uranium abundance. The results showed that the samples contain a significant concentration of uranium with an average of 310.3μg/g, which is 2.6 times higher than the world average of phosphate. The green phosphoric acid obtained from the samples was found to contain uranium in the range of 186-2049μg/g, with an average of 603.3μg/g, and about 98% of uranium content of the phosphate ore was rendered soluble in the phosphoric acid. An extraction process using 25% tributylphosphate, followed by stripping process using 0.5M sodium carbonate reported that more than 98% of uranium in the green phosphoric acid exists as uranyl tricarbonate complex, moreover, sodic decomposition using 50% sodium hydroxide showed that about 98% of the uranium was precipitated as sodium diuranate concentrate that is known as the yellow cake (Na2U2O7). Further purification and calcinations of the yellow cake led to the formation of the orange powder of uranium trioxide (UO3). The chemical analysis of the obtained uranium concentrates; yellow cake and uranium trioxide proved their nuclear purity and that they meet the standard commercial specification. The obtained results proved that uranium from Uro phosphate ore was successfully recovered as uranium trioxide with an overall recovery percentage of 93%. © 2010. Source

Naheid S.A.,Sudan Academy of Sciences | Idris A.M.,King Khalid University | Elgorashe R.E.E.,King Faisal University | Altayeb M.A.H.,Sudan Atomic Energy Commission | And 2 more authors.
Journal of Analytical Chemistry | Year: 2013

This manuscript reports the optimization and validation of a new, rapid, reagent-saving and environmentally-safe method for chlorpromazine assay in pharmaceutical formulations utilizing sequential injection analysis (SIA) technique. Despite its benefits over univariate approach, chemometrics has been rarely exploited for optimizing SIA methods. Moreover, in those methods, some conditions have not been considered in optimization process. In the current study, more conditions, namely volumes and concentrations of reagents, have been optimized by chemometrics for the first time. A developing oxidation reaction of chlorpromazine by permanganate in acidic media was adopted. A spectrophotometric detection of the reduction of permanganate was applied at 526 nm using miniaturized fiber optic devices. The 24 full-factorial design and response surface approaches were exploited for method optimization. The method was validated and realized by a British Pharmacopoeia method. Experimental conditions and analytical aspects of the current SIA method were compared with those of a previous SIA method. Some analytical aspects were comparable while other aspects demonstrated better results from the current method than those from the previous one. The current method is rapid with a sample frequency of 51.4 samples/h. It is also reagent-saving with a total volume of consumed reagents and sample of 260 μL as well as environmental-safety with a total volume of waste production of 1260 μL. The method is therefore efficient for industrial-scale pharmaceutical analysis. © 2013 Pleiades Publishing, Ltd. Source

Sulieman A.,University College of Applied Sciences | Babikir E.,King Saud University | Alrihaima N.,Sudan Atomic Energy Commission | Alkhorayef M.,King Saud University | And 3 more authors.
Applied Radiation and Isotopes | Year: 2016

The objectives of this study were to measure the entrance surface air kerma (ESAK) and the effective doses in pediatric patients undergoing micturating cystourethrography (MCU) procedures. The ESAK was determined using calibrated thermoluminescent dosimeters (TLD- GR 200 A) in 167 pediatric patients. The patient population was categorized into three groups according to age (0-5 years (group 1), 6-10 years (group 2) and 11-15 years (group 3)). The mean ESAK±SD and range (mGy) resulting from a MCU procedure was estimated to be 2.2±0.5 (0.8-9.2), 2.48±0.6 (0.9-8.1) and 3.90±0.6 (1.1-10.3) for group 1, 2 and 3, respectively. The mean effective dose was between 0.03 and 0.4 mSv per procedure for the pediatric population. Pediatric patients were exposed to avoidable radiation doses because no gonad shields were used. © 2016 Elsevier Ltd. Source

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