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    Document

Oxidative Stress Mediated Cytotoxicity of Trichloroethane in a Model of Murine Splenic Injury

The present in vivo murine study was aimed to investigate the long-term effect of repeated administration of low-dose of the environmental toxicant trichloroethane (TCE) over three weeks on the spleen and peripheral blood cells, and the possible role of oxidative stress in TCE-induced toxicity. The results showed neither adverse clinical signs nor mortality on the TCE-treated mice. However, significant changes were noticed in the spleen of those animals. Grossly, the spleen of TCE-treated group was congested and enlarged (splenomegaly). Histpathologically, the splenic tissues of TCE-treated mice showed signs of toxicity as highly activated germinal centers of the white pulp with minimal apoptotic reaction as well as a prominent megakarocytosis and infiltration of the red pulp by comparatively increased number of eosinophiIs and mature lymphocytes were detected. In addition, lymphocyte numbers were decreased in peripheral blood as well as basophils. In contrast, there was an increase in monocyte numbers in the peripheral circulation. In addition, lipid peroxidation/ malondialdehyde formation, a biomarker of oxidative stress, was significantly induced by TCE treatment in the sera and spleen of mice, suggesting an overall increase in oxidative stress. These results provide further support to a role of oxidative stress in TCE-induced cell death, which could result in an impaired spleen function. This study concludes that attenuation of TCE-induced splenic damage in mice provides an approach for preventive and/or therapeutic strategies
Massaud S. Maamar, Mohamed A. Al-Griw, Rabia O. Al-Ghazeer, Seham A. Al-Azreg, Naser M. Salama, Emad M. Bennour(3-2016)
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Cerebellar Organotypic Slice Culture System: A Model of Developing Brain Ischaemia

Ischaemic injury during brain development correlates with long-term neurological problems resulting in part from oligodendrocytes (OL) damage and a loss of appropriate myelination. The molecular and cellular mechanisms responsible remain partially understood and there is no effective clinical treatment. Here we develop and characterise an ex-vivo slice culture ischaemia model to elucidate the cellular mechanisms to aid the search for therapeutic interventions. Cerebellar slices from 7 day-old rats were cultured for 10 days and their developmental profile in culture and their response to oxygen-glucose deprivation (OGD) was assessed. During the culture period development of white matter progressed as in-vivo, the numbers of oligodendrocyte precursor cells (OPC) decreased and the numbers of mature OLs increased and there was extensive myelination of axons as judged by colocalisation of myelin basic protein and neurofilament. Cultured slices were exposed to a short period of OGD at 7 days in-vitro and reperfused to mimic in-vivo conditions. Twenty minutes of OGD was found to result in significant injury as judged by a 58.6% reduction in cell viability 3 days post-injury. Treatment of cultures with OGD resulted in a loss of OLs and a loss of myelination of axons. In summary we have developed a paradigm for studying the damage to OLs and loss of myelination associated with ischaemic periods during development which should facilitate the search for understanding the mechanisms responsible and identifying potential therapeutic interventions.
Mohamed A M Al Griw , Mohamed A. Al-Griw, Ian C. Wood, Michael G. Salter(11-2017)
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Prevalence of Mutations in TAL1 Gene in Individuals With T-ALL and T-NHL

Mutations in the TAL1 (T-cell acute leukemia 1) gene were recently described in patients with T-cell acute lymphoblastic leukaemia (T-ALL) and in those with lymphoblastic T-cell non-Hodgkin’s lymphoma (T-NHL). The purpose of this pilot study was to assess the prevalence of mutations in TAL1 gene in T-ALL and TNHL. DNA samples from 15 unrelated healthy controls, 20 T-ALL patients, and 10 T-NHL patients were analyzed using DNA-PCR and direct DNA sequencing to identify sequence genetic variations in TAL1 gene (exons 2 and 3). TAL1 exon 2 mutations were identified in 7.7% adult and 12.5% adolescent T-ALL patients analyzed. TAL1 exon 2 mutations were detected in 16.7% of the adult TNHL patients analyzed. Sequencing of TAL1 exon 3 showed no sequence variation for the T-ALL and T-NHL cancer patients analyzed. No sex difference where observed in the incidences of TAL1 exons 2 mutations between T-ALL and T-NHL patients with and without TAL1 mutations. TAL1 exon 2 missense and frame-shift mutations were present in 44.4% (4/9) and 55.6% (5/9) of T-ALL patients, respectively. However, the frame-shift and missense mutations in the T-NHL patients accounted for, where respectively, 60% (3/5) and 40% (4/5) of all TAL1 exon 2 mutations. Comparing the clinical features showed that there are no differences in PLT and WBC counts as well as the average age between T-ALL and T-NHL patients with and without TAL1 mutations. Overall, these findings indicate that TAL1 mutations are too rare to be of clinical relevance, and do not seem to be significantly associated with the increased T-ALL and T-NHL susceptibility, implying different pathways with respect to TAL1 genetic polymorphisms as a risk factor for T-ALL and T-NHL at least in this population of Libyans.
Amal E. Elarifi, Othman A. El-Ansari, Mohamed A. Al-Griw(12-2016)
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CYP1A1 Genetic Variations and Lung Cancer Risk in a Population of Libyan Males

Alterations in genes encoding the xenobiotic-metabolizing enzymes contribute to the variability in susceptibility to various cancers. In this study, we assessed the possible association between the CYP1A1 variants and lung cancer (LC) risk in a population of Libyan males. For this study, we selected 20 unrelated healthy controls and 32 patients with LC. DNA samples from the controls and patients were screened by DNA-PCR and direct DNA sequence analysis to search for genetic sequence variations in CYP1A1 gene (exon 7 and 3’ non-coding region). CYP1A1 mutations were identified in 11.5 % adult subjects and cases analyzed, and all were males. Overall, 11 CYP1A1 mutations were documented in this study implicating exon 7 and 3’ non-coding region. Nonsense, missense, and frame-shift mutations accounted for, respectively, 27.3 %, 63.6 % and 9.1 % of all CYP1A1 mutations. Three missense mutations namely CYP1A1*2B/m2 (rs1048943), CYP1A1*4/m4 (rs1799814), and CYP1A1*2A/m1 (rs4646903) have already been reported. The remaining mutations have not been described previously. We observed two apparently heterozygous carriers of mutation CYP1A1*2B/m2 (CYP1A1 4889A/G [642Ile/Val] genotype) in control group. We also observed two heterozygotic genotypes one containing mutation m4 (CYP1A1 4887C/A [461Thr/Asp]) and another containing mutation m1 (6235T/C) in cancer group. The mutations m2, m4, and m1 accounted for, respectively, 18.2 %, 9.1 % and 9.1 % of all CYP1A1 mutations. Comparing the clinical features showed that PLT and WBC counts were lower in CYP1A1 mutant than in CYP1A1 wild type, but they have not reached statistical significant (P > 0.05). The average age of CYP1A1 mutant was lower than in CYP1A1 wild type. Overall, these findings suggest that genetic alterations in the metabolic gene CYP1A1 are too rare to be of clinical relevance in this study, implying different pathways for the LC risk with respect to CYP1A1 polymorphisms as a risk factor for LC at least in this study.
Najah A. Fares, Othman A. El-Ansari, Mohamed A. Al-Griw(4-2017)
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Cellular and molecular etiology of hepatocyte injury in a murine model of environmentally induced liver abnormality

Exposures to a wide variety of environmental substances are negatively associated with many biological cell systems both in humans and rodents. Trichloroethane (TCE), a ubiquitous environmental toxicant, is used in large quantities as a dissolvent, metal degreaser, chemical intermediate, and component of consumer products. This increases the likelihood of human exposure to these compounds through dermal, inhalation and oral routes. The present in vivo study was aimed to investigate the possible cellular and molecular etiology of liver abnormality induced by early exposure to TCE using a murine model. The results showed a significant increase in liver weight. Histopathological examination revealed a TCE-induced hepatotoxicity which appeared as heavily congested central vein and blood sinusoids as well as leukocytic infiltration. Mitotic figures and apoptotic changes such as chromatin condensation and nuclear fragments were also identified. Cell death analysis demonstrates hepatocellular apoptosis was evident in the treated mice compared to control. TCE was also found to induce oxidative stress as indicated by an increase in the levels of lipid peroxidation, an oxidative stress marker. There was also a significant decrease in the DNA content of the hepatocytes of the treated groups compared to control. Agarose gel electrophoresis also provided further biochemical evidence of apoptosis by showing internucleosomal DNA fragmentation in the liver cells, indicating oxidative stress as the cause of DNA damage. These results suggest the need for a complete risk assessment of any new chemical prior to its arrival into the consumer market.
Mohamed M. Al-Griw, Rabia O. Alghazeer, S. A. Al-Azreg, Emad M. Bennour(9-2016)
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Effects of storage temperature on the quantity and integrity of genomic DNA extracted from mice tissues: A comparison of recovery methods

Efficient extraction of genomic DNA (gDNA) from biological materials found in harsh environments is the first step for successful forensic DNA profiling. This study aimed to evaluate two methods for DNA recovery from animal tissues (livers, muscles), focusing on the best storage temperature for DNA yield in term of quality, quantity, and integrity for use in several downstream molecular techniques. Six male Swiss albino mice were sacrificed, liver and muscle tissues (n=32) were then harvested and stored for one week in different temperatures, -20C, 4C, 25C and 40C. The conditioned animal tissues were used for DNA extraction by Chelex-100 method or NucleoSpin Blood and Tissue kit. The extracted gDNA was visualized on 1.5% agarose gel electrophoresis to determine the quality of gDNA and analysed spectrophotometrically to determine the DNA concentration and the purity. Both methods, Chelex-100 and NucleoSpin Blood and Tissue kit found to be appropriate for yielding high quantity of gDNA, with the Chelex100 method yielding a greater quantity (P < 0.045) than the kit. At -20C, 4C, and 25C temperatures, the concentration of DNA yield was numerically lower than at 40C. The NucleoSpin Blood and Tissue kit produced a higher (P=0.031) purity product than the Chelex-100 method, particularly for muscle tissues. The Chelex-100 method is cheap, fast, effective, and is a crucial tool for yielding DNA from animal tissues (livers, muscles) exposed to harsh environment with little limitations.
Huda H. Al-Griw, Zena A. Zraba, Salsabiel K. Al-Muntaser, Marwan M. Draid, Aisha M. Zaidi, Refaat M. Tabagh , Mohamed A. Al-Griw(8-2017)
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دليل الوصف المورفولوجي وتصنيف قطاع التربة في الحقل

بتوفيق من الله تم إعداد هذا الكتيب لمساعدة المهندسين والطلبة والباحثين الذين يقومون بإجراء وصف قطاعات التربة في الحقل أثناء دراسات التربة الحقلية أوإجراء بعض البحوث في هذا المجال, حيث أن الكم الهائل من المعلومات والملاحظات التي يجب تدوينها وتجميعها من خلال الوصف الحقلي لقطاع التربة وكذلك المصطلحات العلمية التي يتعذر في كثير من الأحيان تذكرها بصورة مرتبة. عليه ،،،،،،،،،،،،،، لقد حاولنا أن نضع كافة خبرتنا المتواضعة التى اكتسبناها لتسهيل المهمة ويكون هذا الدليل بين أيدي طلبة قسم التربة والمياه والمهتمين بهذا المجال , وذلك لمساعدتهم في إختيارالمصطلحات العلمية المطلوبة والمناسبة ووضعها في مكانها الصحيح مع توحيد هذه المصطلحات وتعريبها بين المستخدمين في هذا المجال. كما يوضح هذا الكتيب الخطوات العلمية الصحيحة لوصف قطاع التربة في الحقل. حيث أنه كلما كان وصف قطاع التربة في الحقل دقيقاً والمصطلحات المستخدمة في مكانها الصحيح كان تصنيف التربة أقرب إلى الواقع ، وبالتالي يكون تقييم خصائص التربة المختلفة واقعياً حتى يتم استخدامها الاستخدام الأمثل والتعرف على مشاكلها بصورة صحيحة , وكذلك وضع برامج الإدارة الفنية المناسبة للتربة للحد من مشاكل أستزراعها. ولقد تم التركيز أيضاً في هذا الكتيب على تصنيف الترب السائدة بكامل أرجاء ليبيا وهي في مجموعها 6 رتب من مجموع 12 رتبة على مستوى العالم وذلك وفق النظام الأمريكي الحديث لتصنيف التربة والمعتمد في دراسات تصنيف التربة فى ليبيا. ويوضح هذا الكتيب أيضاً مستوى تحت الرتب التي يمكن التعرف عليها في الحقل من خلال الوصف المورفولوجي لقطاع التربة والبيئة المحيطة به. كذلك يركز هذا الكتيب على ترتيب ونوعية الآفاق الوراثية أو البيدوجينية بمستوى تحت الرتب المتواجدة بالبيئة الليبية مع تحديد الأفاق التشخيصية السطحية وتحت السطحية المميزة بهذه المستويات مع وضع رسومات توضيحية كلما أمكن ذلك. كما يرفق مع هذا الكتيب النموذج المعتمد لوصف قطاع التربة بالحقل والبيئة المحيطة به وكذلك نموذج تفسير النتائج. والله ولي التوفيق المؤلفان
د.عزالدين الطيب الحويج , مختار محمود مختار العالم(5-2012)

A Comparison of Fuzzy AHP and Ideal Point Methods for Evaluating Land Suitability

This article compares two fuzzy approaches to land suitability evaluations, Analytical Hierarchy Process (AHP) and Ideal Point. The methods were evaluated using a case study which models the opportunities for wheat production under irrigation conditions in the north‐western region of Jeffara Plain, Libya. A number of relevant soil and landscape criteria were identified through a review of the literature and their weights specified as a result of discussions with local experts. The results of the Fuzzy AHP showed that the majority of the study area has membership values to the set of suitability between 0.40 and 0.50, while the results of the Ideal Point approach revealed most of the study area to have membership values between 0.30 and 0.40. While the Fuzzy AHP and Ideal Point approaches accommodate the continuous nature of many soil properties and produce more intuitive distributions of land suitabilities values, the Fuzzy AHP approach was found to be better than Fuzzy Ideal Point. This was due to the latter's tendency to be biased towards positive and negative ideal values
Mukhtar Elaalem, Alexis Comber, Pete Fisher(6-2011)
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