Study on the Effect of the Self-Attenuation Coefficient on γ-ray Detector Efficiency Calculated at Low and High Energy Regions

Ahmed. M. El-Khatib,ABOUZEID. A. THABET,MOHAMED. A. ELZAHER,MOHAMED. S. BADAWI,BOHAYSA. A. SALEM 한국원자력학회 2014 Nuclear Engineering and Technology Vol.46 No.2

The present work used the efficiency transfer method used to calculate the full energy peak efficiency (FEPE) curves ofthe (2"*2" & 3"*3") NaI (Tl) detectors based on the effective solid angle subtended between the source and the detector. Thestudy covered the effect of the self attenuation coefficient of the source matrix (with a radius greater than the detector's radius)on the detector efficiency. 152 An Eu aqueous radioactive source covering the energy range from 121.78 keV up to 1408.01keV was used. In this study an empirical formula was deduced to calculate the difference between the measured and thecalculated efficiencies [without self attenuation] at low and high energy regions. A proper balance between the measured andcalculated efficiencies [with self attenuation] was achieved with discrepancies less than 3%, while reaching 39% forcalculating values [without self attenuation] due to working with large sources, or for low photon energies.

Assessment and management of coagulopathy in neurocritical care

Ahmed M. Salem,David Roh,Ryan S. Kitagawa,Huimahn A. Choi,Tiffany R. Chang 대한신경집중치료학회 2019 대한신경집중치료학회지 Vol.12 No.1

Coagulopathy may be defined as the loss of balance between hemostatic and fibrinolytic processes resulting in excessive bleeding, intravascular thrombosis or abnormalities in coagulation testing. It is frequently encountered across a wide range of conditions seen in the neurocritical care unit and can contribute to poor outcomes. Early recognition and appropriate management are key, with traumatic brain injury, acute ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage presenting unique challenges to the neurointensivist. We will discuss techniques to assess coagulopathies as well as treatment strategies for the brain injured patient.

Evaluation of genotoxicity and mutagenicity of aqueous extracts of Rhazya stricta Decne. and Thymus vulgaris L.

Shatha Salem Hameed,M‑Zaki Mustafa ElAssouli,Ahmed M. Al-Hejin,Mohammad Zubair Alam,Sufian Mohamad ElAssouli,Faten Zubair Filimban 경희대학교 융합한의과학연구소 2018 Oriental Pharmacy and Experimental Medicine Vol.18 No.4

Traditional herbal medicines have been part of human healthcare systems since ancient times. The studies on herbal medicines have mainly focused on their beneficial aspects and hence their harmful effects have been usually overlooked. Throughout Middle East and South Asia, Rhazya stricta Decne. and Thymus vulgaris L. are used as traditional medicines for various diseases. We evaluated R. stricta and T. vulgaris aqueous extracts for their genotoxicity and mutagenicity through comet assay and Ames Salmonella mutagenicity test respectively. An overall treatment effect (p < 0.0001) showed higher genotoxicity of T. vulgaris extract indicated by increased tail moments in comet assay compared to the extract of R. stricta and the combined extract. Further, an overall dose effect (p < 0.0001) showed higher genotoxicity at 1 mg/ml which further increased at 5 mg/ml doses of the extracts compared to 0 mg/ml. The genotoxicity did not show any further increase at 10 mg/ml. The extracts were also tested for their mutagenicity through Ames Salmonella test. R. stricta and T. vulgaris were not mutagenic to TA100 and TA98 when extracts tested separately. However, combined extracts of R. stricta and T. vulgaris was weakly mutagenic to TA98 with number of revertants 92 ± 8 at the highest concentration tested. This study implies that the herbal medicines should be used cautiously as they may cause long term harmful effects along with the intended beneficial activity.

Precipitation–deposition assisted fabrication and characterization of nano-sized zinc manganite

N.M. Deraz,Ahmed A. Abdeltawab,M.M. Selim,O. El-Shafey,A.A. El-Asmy,Salem S Al-Deyab 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.5

Catalytic and structural investigations of nano-sized zinc manganite (ZnMn2O4) powders have been determined. These manganites were prepared by precipitation–deposition route followed by heating at 400, 600, and 800℃. The final products were characterized X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray (EDX). The catalytic activity of the as prepared systems was measured by the hydrogen peroxide decomposition in aqueous solution over the solid surface at 30–50℃. The results showed that the calcination temperature affects the different characteristics of the investigated solids.

A novel method for improving the microstructure and electrical properties of Pr6O11-based ZnO varistors

Qaid Salem A. S.,Issa M. A. A.,Hassib A. M.,Al-Asbahi Bandar Ali,Abuassaj E. M.,Ahmed Abdullah Ahmed Ali 한국세라믹학회 2022 한국세라믹학회지 Vol.59 No.6

The eff ects of diff erent synthesis routes and sintering temperatures on the microstructures and electrical properties of ceramic varistors (composed of ZnO doped with Pr 6O11, Co 3O4, Cr 2O3, and Nd 2O3) were investigated. Two types of samples were prepared according to the milling approach (single-mill or double-mill). Remilling the calcined powder material reduced the required sintering temperature by 100 °C, improved the microstructure of the ceramic, and enhanced the nonlinear properties of the varistor. Though the diff erent sintering temperatures and average grain sizes, both types were reach ≈ 98% of the theoretical density. The highest nonlinear coeffi cient value was ≈ 26.5, obtained from the fi rst sample of the double- mill batch. As the sintering temperature increased, the nonlinearity diminished rapidly in the case of single-mill samples compared to double-mill ones. Similar behavior was noted for the varistor (breakdown) voltage. The thermionic emission behavior at the pre-breakdown region and the conduction mechanism through Schottky barriers were applied to fi nd further electrical parameters.

Hibiscus sabdariffa L.: phytoconstituents, nutritive, and pharmacological applications

Mohamed A. Salem,Ahmed Zayed,Magy E. Beshay,Mesih Mirna M. Abdel,Khayal Reem F. Ben,Fady A. George,Shahira M. Ezzat 경희대학교 융합한의과학연구소 2022 Oriental Pharmacy and Experimental Medicine Vol.22 No.3

Hibiscus sabdariffa L. (HS) calyx extracts have been well-documented for the treatment of hypertension, liver dysfunctions, and diabetes among others. An updated concise review of HS regarding phytoconstituents, and involved putative mechanisms of potential biological activities is presented. HS showed other food and other industrial applications, including the preparation of metallic nanoparticles. These activities were explained by the presence of a broad spectrum of valuable phytochemicals, including the red pigments anthocyanins, phenolic, and organic acids and polyphenolics (e.g., flavonoids and tannins). Most of the bioactivities were found to be associated with anthocyanins-rich extracts. Anthocyanins were found to have various mechanisms for the treatment of hypertension, including direct vasodilation and inhibition of angiotensinconverting enzyme (ACE). However, leaves and seeds showed also other potential applications in food industry, owing to the significant amounts of phenolic antioxidant compounds. Therefore, valorization and optimization of bioactive constituents’ extraction from plant biowastes should be considered for maximizing the benefits of HS extracts.

STUDY ON THE EFFECT OF THE SELF-ATTENUATION COEFFICIENT ON γ-RAY DETECTOR EFFICIENCY CALCULATED AT LOW AND HIGH ENERGY REGIONS

El-Khatib, Ahmed M.,Thabet, Abouzeid A.,Elzaher, Mohamed A.,Badawi, Mohamed S.,Salem, Bohaysa A. Korean Nuclear Society 2014 Nuclear Engineering and Technology Vol.46 No.2

The present work used the efficiency transfer method used to calculate the full energy peak efficiency (FEPE) curves of the (2"*2" & 3"*3") NaI (Tl) detectors based on the effective solid angle subtended between the source and the detector. The study covered the effect of the self attenuation coefficient of the source matrix (with a radius greater than the detector's radius) on the detector efficiency. $^{152}$ An Eu aqueous radioactive source covering the energy range from 121.78 keV up to 1408.01 keV was used. In this study an empirical formula was deduced to calculate the difference between the measured and the calculated efficiencies [without self attenuation] at low and high energy regions. A proper balance between the measured and calculated efficiencies [with self attenuation] was achieved with discrepancies less than 3%, while reaching 39% for calculating values [without self attenuation] due to working with large sources, or for low photon energies.

Novel Mutations in the Displacement Loop of Mitochondrial DNA are Associated with Acute Lymphoblastic Leukemia: A Genetic Sequencing Study

Yacoub, Haitham Ahmed,Mahmoud, Wael Mahmoud,El-Baz, Hatim Alaa El-Din,Eid, Ola Mohamed,ELfayoumi, Refaat Ibrahim,Elhamidy, Salem Mohamed,Mahmoud, Maged M. Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.21

Background: Acute lymphoblastic leukemia (ALL) is the most common cancer diagnosed in children and represents approximately 25% of cancer diagnoses among those younger than 15 years of age. Materials and Methods: This study investigated alterations in the displacement loop (d-loop) region of mitochondrial DNA (mtDNA) as a risk factor and diagnostic biomarker for early detection and diagnosis of acute lymphoblastic leukemia. Using mtDNA from 23 subjects diagnosed with acute lymphoblastic leukemia, the first 450 bp of the d-loop region were amplified and successfully sequenced. Results: This revealed 132 mutations at 25 positions in this region, with a mean of 6 alterations per subject. The d-loop alterations in mtDNA in subjects were all identified as single nucleotide polymorphisms in a homoplasmic distribution pattern. Mutant alleles were observed in all subjects with individual frequency rates of up to 95%. Thirteen mutant alleles in the d-loop region of mtDNA occurred with a high frequency. Novel alleles and locations were also identified in the d-loop of mtDNA as follows: 89 G insertions (40%), 95 G insertions (13%), 182 C/T substitutions (5%), 308 C insertions (19%), and 311 C insertions (80%). The findings of this study need to be replicated to be confirmed. Conclusions: Further investigation of the relationship between mutations in mitochondrial d-loop genes and incidence of acute lymphoblastic leukemia is recommended.

Possible Therapeutic Uses of Salvia triloba and Piper nigrum in Alzheimer's Disease–Induced Rats

Hanaa H. Ahmed,Ahmed M. Salem,Gilane M. Sabry,Ahmed A. Husein,Soheir E. Kotob 한국식품영양과학회 2013 Journal of medicinal food Vol.16 No.5

This study aimed to investigate the role of Salvia triloba L. and Piper nigrum extracts in ameliorating neuroinflammatory insults characteristic of Alzheimer's disease (AD) in an experimentally induced rat model. Adult male Sprague-Dawley rats were classified into Group 1 (n=10): normal healthy animals serving as the negative control group; Group 2 (n=60): the AD-induced group. After AD induction, animals in the AD-induced group were divided randomly and equally into 6 subgroups. The first subgroup served as AD control; the second one, which served as positive control, was treated orally with the conventional therapy for AD (rivastigmine) at a dose of 0.3 mg/kg body weight (b.w.) daily for 3 months. The third and fourth subgroups were, respectively, treated orally with the S. triloba extract at a dose of 750 and 375 mg/kg b.w. daily for 3 months. The fifth and sixth subgroups were, respectively, treated orally with the P. nigrum extract at a dose of 187.5 and 93.75 mg/kg b.w. daily for 3 months. Levels of brain acetylcholine (Ach), serum and brain acetylcholinesterase (AchE) activity, C-reactive protein (CRP), total nuclear factor kappa-B (NF-κB), and monocyte chemoattractant protein-1 (MCP-1) were estimated. The results showed that administration of AlCl3 resulted in a significant elevation in the levels of AchE activity, CRP, NF-κB, and MCP-1 accompanied with a significant depletion in the Ach level. Treatment of AD rats with each of the selected medicinal plant extracts caused marked improvement in the measured biochemical parameters. In conclusion, S. triloba and P. nigrum methanolic extracts have potent anti-inflammatory effects against neuroinflammation characterizing AD.

MicroRNAs and Metastasis-related Gene Expression in Egyptian Breast Cancer Patients

Hafez, Mohamed M.,Hassan, Zeinab K.,Zekri, Abdel Rahman N.,Gaber, Ayman A.,Rejaie, Salem S. Al,Sayed-Ahmed, Mohamed M.,Shabanah, Othman Al Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.2

Aim and background: MicroRNAs (miRNAs) are a class of naturally occurring small noncoding RNAs that regulate gene expression, cell growth, differentiation and apoptosis by targeting mRNAs for translational repression or cleavage. The present study was conducted to study miRNAs in Egyptian breast cancer (BC) and their relation to metastasis, tumor invasion and apoptosis in addition to their association with the ER and PR statuses. Methods: Real Time RT-PCR was performed to identify the miRNA expression level of eight miRNAs and eight metastatic-related genes in 40 breast cancer samples and their adjacent non-neoplastic tissues. The expression levels of each miRNA relative to U6 RNA were determined using the $^{2-{\Delta}}CT$ method. Also, miRNA expression profiles of the BC and their corresponding ANT were evaluated. Results: The BC patients showed an up-regulation in miRNAs (mir-155, mir-10, mir-21 and mir-373) with an upregulation in MMP2, MMp9 and VEGF genes. We found down regulation in mir-17p, mir-126, mir-335, mir-30b and also TIMP3, TMP1 and PDCD4 genes in the cancer tissue compared to the adjacent non-neoplastic tissues. Mir -10b, mir -21, mir-155 and mir373 and the metastatic genes MMP2, MMP9 and VEGF were significantly associated with an increase in tumor size (P < 0.05). No significant difference was observed between any of the studied miRNAs regarding lymph node metastasis. Mir-21 was significantly over-expressed in ER-/PR-cases. Conclusion: Specific miRNAs (mir-10, mir-21, mir-155, mir-373, mir-30b, mir-126, mir-17p, mir-335) are associated with tumor metastasis and other clinical characteristics for BC, facilitating identification of individuals who are at risk.