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      • KCI등재

        Comparing the Passive Sampler and Biomonitoring of Organic Pollutants in Water: A Laboratory Study

        Nahla S. El-Shenawy,Richard Greenwood,Ismail M. Abdel-Nabi,Zohour I. Nabil 한국해양과학기술원 2009 Ocean science journal Vol.44 No.2

        Passive sampling could provide the solution to problems associated with costly and time consuming sampling programmes and biomonitoring. Mussels (Mytilus edulis) and Chemcatcher passive sampler were simultaneously analyzed for sequestered pesticides and polychlorinated biphenyls (PCBs) by gas chromatography with mass spectrometry (GC/MSD). The Chemcatcher passive sampler based on a solid phase extraction disc with two types of diffusion-limiting membranes (polyethelene and polysulphone), were also compared. Diuron, atrazine, irgarol and lindane were accumulated in the polysulphone passive sampler in greater concentration than in the mussels or in the other passive samplers with polyethelene limiting-membrane. Mussels can accumulate in their tissue high concentration of non polar compounds such as PCB 52, dieldren and PCB 153; more than the passive sampler with polysulphone membrane. The device with polyethelene limiting membrane has high affinity capacity to concentrate high amount of phenenthrene, dieldrin, PCB 153 and PCB 52, so it acts as a sampler for non-polar compounds. The highest uptake rate of hydrophobic compounds by Chemcatcher was observed for analytes with log octanol-water partition coefficient (KOW) between 4.5 and 7.5. Laboratorybased studies using passive samplers to assess the potential for bioaccumulation could provide robust and reliable information at relatively low cost compared to biomonitoring data. Laboratory data obtained using passive samplers could be related to accumulation under field conditions where field assessments are required. Passive sampling could provide the solution to problems associated with costly and time consuming sampling programmes and biomonitoring. Mussels (Mytilus edulis) and Chemcatcher passive sampler were simultaneously analyzed for sequestered pesticides and polychlorinated biphenyls (PCBs) by gas chromatography with mass spectrometry (GC/MSD). The Chemcatcher passive sampler based on a solid phase extraction disc with two types of diffusion-limiting membranes (polyethelene and polysulphone), were also compared. Diuron, atrazine, irgarol and lindane were accumulated in the polysulphone passive sampler in greater concentration than in the mussels or in the other passive samplers with polyethelene limiting-membrane. Mussels can accumulate in their tissue high concentration of non polar compounds such as PCB 52, dieldren and PCB 153; more than the passive sampler with polysulphone membrane. The device with polyethelene limiting membrane has high affinity capacity to concentrate high amount of phenenthrene, dieldrin, PCB 153 and PCB 52, so it acts as a sampler for non-polar compounds. The highest uptake rate of hydrophobic compounds by Chemcatcher was observed for analytes with log octanol-water partition coefficient (KOW) between 4.5 and 7.5. Laboratorybased studies using passive samplers to assess the potential for bioaccumulation could provide robust and reliable information at relatively low cost compared to biomonitoring data. Laboratory data obtained using passive samplers could be related to accumulation under field conditions where field assessments are required.

      • KCI등재

        Prediction and Staging of Hepatic Fibrosis in Children with Hepatitis C Virus: A Machine Learning Approach

        Nahla H. Barakat,Sana H. Barakat,Nadia Ahmed 대한의료정보학회 2019 Healthcare Informatics Research Vol.25 No.3

        Objectives: The aim of this study is to develop an intelligent diagnostic system utilizing machine learning for data cleansing, then build an intelligent model and obtain new cutoff values for APRI (aspartate aminotransferase-to-platelet ratio) and FIB- 4 (fibrosis score) for the prediction and staging of fibrosis in children with chronic hepatitis C (CHC). Methods: Random forest (RF) was utilized in this study for data cleansing; then, prediction and staging of fibrosis, APRI and FIB-4 scores and their areas under the ROC curve (AUC) have been obtained on the cleaned dataset. A cohort of 166 Egyptian children with CHC was studied. Results: RF, APRI, and FIB-4 achieved high AUCs; where APRI had AUCs of 0.78, 0.816, and 0.77; FIB- 4 had AUCs of 0.74, 0.828, and 0.78; and RF had AUCs of 0.903, 0.894, and 0.822, for the prediction of any type of fibrosis, advanced fibrosis, and differentiating between mild and advanced fibrosis, respectively. Conclusions: Machine learning is a valuable addition to non-invasive methods of liver fibrosis prediction and staging in pediatrics. Furthermore, the obtained cutoff values for APRI and FIB-4 showed good performance and are consistent with some previously obtained cutoff values. There was some agreement between the predictions of RF, APRI and FIB-4 for the prediction and staging of fibrosis.

      • KCI등재

        Histopathologic Biomarker Response of Clam, Ruditapes decussates, to Organophosphorous Pesticides Reldan and Roundup: A Laboratory Study

        Nahla S. El-Shenawy,Tarak I. S. Moawad,Mahmoud E. Mohallal,Ismail M. Abdel-Nabi,Inas A. Taha 한국해양과학기술원 2009 Ocean science journal Vol.44 No.1

        Clam Ruditapes decussates was used as a biomonitoring organism to measure the potential impact of pollution. The present study investigated histological alterations of R. decussates following a long-term exposure to a sublethal-level of pesticides Reldan and Roundup. The clams were taken to the laboratory and kept for days to adjust to a continuous closed flow system with quality water control. After the adjustment period, clams were exposed either to sublethal concentrations of Reldan (0.6 μl L−1) or Roundup (1.1 μl L−1) for 90 days. Clams were taken to determine the histological damage at 30, 60 and 90 days. Most histological alterations were highly localized in the glandular cells of the gills, mantle tissues and digestive gland; secretions of glandular cells were found to be increased by increasing the time of exposure. Histopathological results showed the activation of resistance mechanisms that allowed the clams to survive under sublethal stresses. Thus, histological changes on localized tissues were sensitive and they have positive correlation to the time of exposure to the pesticides, suggesting that they may serve as biomarkers for Reldan and Roundup exposures. Clam Ruditapes decussates was used as a biomonitoring organism to measure the potential impact of pollution. The present study investigated histological alterations of R. decussates following a long-term exposure to a sublethal-level of pesticides Reldan and Roundup. The clams were taken to the laboratory and kept for days to adjust to a continuous closed flow system with quality water control. After the adjustment period, clams were exposed either to sublethal concentrations of Reldan (0.6 μl L−1) or Roundup (1.1 μl L−1) for 90 days. Clams were taken to determine the histological damage at 30, 60 and 90 days. Most histological alterations were highly localized in the glandular cells of the gills, mantle tissues and digestive gland; secretions of glandular cells were found to be increased by increasing the time of exposure. Histopathological results showed the activation of resistance mechanisms that allowed the clams to survive under sublethal stresses. Thus, histological changes on localized tissues were sensitive and they have positive correlation to the time of exposure to the pesticides, suggesting that they may serve as biomarkers for Reldan and Roundup exposures.

      • Experimental evaluation of the performance of self-compacting concrete contains nano clay and nano egg shell

        Hilal, Nahla N.,Hadzima-Nyarko, Marijana Techno-Press 2022 Advances in concrete construction Vol.13 No.5

        The rising prices of landfills and the lack of cement production are motivating researchers to be more interested in using wastes to produce concrete mixtures materials. The use of waste materials such as eggshell and matakoline waste not only reduces landfill costs and space, but also reduces the cost of cement production for the concrete mixture. However, recycling waste materials has become critical in order to effectively manage environmental sustainability. The purpose of this paper is to investigate the appropriate properties of self-compacting concrete (SCC) by incorporating waste materials such as crushed ceramics as coarse aggregate and nano egg shell (NES) and nanoclay (NC) as cement replacements. Fresh properties of SCC, such as segregation, flow time and diameter, V-funnel, H2/H1 ratio, and fresh unit weight of concrete mixtures, as well as hardened properties, such as 7, 14, and 28 days compressive strength and 28 and 90 days flexural strength, were measured for this purpose. The presence of NC in the SCC mixture enhanced the compressive strength of the concrete when 5% of NES was added or in the case without the addition of NES compared to the control mixture. The flexural strength enhanced with the incorporation of NC in the SCC increased the flexural strength of the concrete compared to the control mixture, but the incorporation of 5% of NES decreased the flexural strength compared to the mixtures with NC. These results prove the possibility of using crushed ceramics as the coarse aggregate, and NES and NC as substitutes for 5, 7, and 10% of the cement in SCC, because the properties of such SCC in hardened and fresh states are satisfactory.

      • Masked Face Recognition via a Combined SIFT and DLBP Features Trained in CNN Model

        Aljarallah, Nahla Fahad,Uliyan, Diaa Mohammed International Journal of Computer ScienceNetwork S 2022 International journal of computer science and netw Vol.22 No.6

        The latest global COVID-19 pandemic has made the use of facial masks an important aspect of our lives. People are advised to cover their faces in public spaces to discourage illness from spreading. Using these face masks posed a significant concern about the exactness of the face identification method used to search and unlock telephones at the school/office. Many companies have already built the requisite data in-house to incorporate such a scheme, using face recognition as an authentication. Unfortunately, veiled faces hinder the detection and acknowledgment of these facial identity schemes and seek to invalidate the internal data collection. Biometric systems that use the face as authentication cause problems with detection or recognition (face or persons). In this research, a novel model has been developed to detect and recognize faces and persons for authentication using scale invariant features (SIFT) for the whole segmented face with an efficient local binary texture features (DLBP) in region of eyes in the masked face. The Fuzzy C means is utilized to segment the image. These mixed features are trained significantly in a convolution neural network (CNN) model. The main advantage of this model is that can detect and recognizing faces by assigning weights to the selected features aimed to grant or provoke permissions with high accuracy.

      • Clinical Significance of Co-expression of Aberrant Antigens in Acute Leukemia: A Retrospective Cohort Study in Makah Al Mukaramah, Saudi Arabia

        Abdulateef, Nahla Ahmad Bahgat,Ismail, Manar Mohammad,Aljedani, Hanadi Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.1

        Background: Aberrant phenotypes in acute leukemia have variable frequency and their prognostic and predictive relevance is controversial, despite several reports of clinical significance. Aims: To determine the prevalence of aberrant antigen expression in acute leukemia, assess clinical relevance and demonstrate immunophenotype-karyotype correlations. Materials and Methods: A total of 73 (40 AML and 33 ALL) newly diagnosed acute leukemia cases presenting to KAMC, Kingdom of Saudi Arabia, were included. Diagnosis was based on WHO criteria and FAB classification. Immunophenotyping by flow cytometry, conventional karyotyping and fluorescence in situ hybridization for gene rearrangements were performed. Results: Aberrant antigens were detected in 27/40 (67.5%) of AML and in 14/33 (42.4%) in ALL cases. There were statistically significant higher TLC in Ly+ AML than in Ly-AML (p=0.05) and significant higher blast count in ALL with aberrant antigens at presentation and day 14 (p=0.005, 0.046). There was no significant relation to clinical response, relapse free survival (RFS) or overall survival (p>0.05), but AML cases expressing ${\geq}2$ Ly antigens showed a lower median RFS than those expressing a single Ly antigen. In AML, CD 56 was expressed in 11/40. CD7 was expressed in 7/40, having a significant relation with an unfavorable cytogenetic pattern (p=0.046). CD4 was expressed in 5/40. CD19 was detected in 4/40 AML associated with M2 and t (8; 21). In ALL cases, CD33 was expressed in 7/33 and CD13 in 5/33. Regarding T Ag in B-ALL CD2 was expressed in 2 cases and CD56 in 3 cases. Conclusions: Aberrant antigen expression may be associated with adverse clinical data at presentation. AML cases expressing ${\geq}2$ Ly antigens may have shorter median RFS. No specific cytogenetic pattern is associated with aberrant antigen expression but individual antigens may be related to particular cytogenetic patterns. Immunophenotype-karyotype correlations need larger studies for confirmation.

      • KCI등재

        Histopathologic Biomarker Response of Clam, Ruditapes decussates, to Organophosphorous Pesticides Reldan and Roundup: A Laboratory Study

        El-Shenawy, Nahla S.,Moawad, Tarak I.S.,Mohallal, Mahmoud E.,Abdel-Nabi, Ismail M.,Taha, Inas A. 한국해양학회 2009 Ocean science journal Vol.44 No.1

        Clam Ruditapes decussates was used as a biomonitoring organism to measure the potential impact of pollution. The present study investigated histological alterations of R. decussates following a long-term exposure to a sublethal-level of pesticides Reldan and Roundup. The clams were taken to the laboratory and kept for days to adjust to a continuous closed flow system with quality water control. After the adjustment period, clams were exposed either to sublethal concentrations of Reldan (0.6 $\mu$l $L^{-1}$) or Roundup (1.1 $\mu$l $L^{-1}$) for 90 days. Clams were taken to determine the histological damage at 30, 60 and 90 days. Most histological alterations were highly localized in the glandular cells of the gills, mantle tissues and digestive gland; secretions of glandular cells were found to be increased by increasing the time of exposure. Histopathological results showed the activation of resistance mechanisms that allowed the clams to survive under sublethal stresses. Thus, histological changes on localized tissues were sensitive and they have positive correlation to the time of exposure to the pesticides, suggesting that they may serve as biomarkers for Reldan and Roundup exposures.

      • KCI등재

        Poly(DMAEMA-co-MPS) Coated Mesoporous Silica Nanoparticles as Smart Drug Carriers with pH-controlled on-off Release

        Mohammad Hegazy,Nahla Rahoui,Ahmed Abou- Elyazed,Diaa Eldin Fouad,Xin Huang,Yudong Huang 한국고분자학회 2019 폴리머 Vol.43 No.3

        In this paper, pH-responsive nanocarriers based on mesoporous silica nanoparticles (MSN) modified with the pH-sensitive polymer: poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) were constructed, characterized and tested to evaluate their efficacy as drug delivery systems (DDS). The hybrid nanocarriers were synthesized successfully via a simultaneous copolymerization reaction between two monomers; 2-dimethylamino-ethylmethacrylate (DMAEMA) and 3-methacryloxypropyltrimethoxysilane (MPS) within the mesopores of MSN. Exploiting the polymerizable moiety of MPS together with its alkoxysilane moity susceptible to condensation with silanols surface onto silica, MPS comonomer can act as a bridge for yielding a robust and simple hybrid consisting of MSN-P(DMAEMA-co-MPS). In addition, the grafted PDMAEMA serves as efficient gatekeeper to adjust the encapsulation and in vitro release of cargos loaded inside the pores by altering pH values of the medium. These hybrid nanoparticles showed a high loading capacity with quick release in acidic pH, which exists mainly in the diseases environments e.g. inflammatory and cancerous sites.

      • KCI등재

        Anti-proliferative Effects of Androctonus amoreuxi Scorpion and Cerastes cerastes Snake Venoms on Human Prostate Cancer Cells

        Hassan Akef,Nahla Kotb,Dina Abo-Elmatty,Sayed Salem 대한암예방학회 2017 Journal of cancer prevention Vol.22 No.1

        The present study evaluated the effects of Androctonus amoreuxi scorpion venom, Cerastes cerastes snake venom and their mixture on prostate cancer cells (PC3). An MTT assay was used to determine the anti-proliferative effect of the venoms, while quantitative real time PCR was used to evaluate the expression of apoptosis-related genes (Bax and Bcl-2). Furthermore, colorimetric assays were used to measure the levels of malondialdehyde (MDA) and antioxidant enzymes. Our results show that the venoms significantly reduced PC3 cell viability in a dose-dependent manner. On the other hand, these venoms significantly decreased Bcl-2 gene expression. Additionally, C. cerastes venom significantly reduced Bax gene expression, while A. amoreuxi venom and a mixture of A. amoreuxi & C. cerastes venoms did not alter Bax expression. Consequently, these venoms significantly increased the Bax/Bcl-2 ratio and the oxidative stress biomarker MDA. Furthermore, these venoms also increased the activity levels of the antioxidant enzymes, catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, and glutathione-S-transferase. Overall, the venoms have cytotoxic and anti-proliferative effects on PC3 cells.

      • KCI등재

        A Flavonol Triglycoside and Investigation of the Antioxidant and Cell Stimulating Activities of Annona muricata Linn.

        Mahmoud Nawwar,Nahla Ayoub,Sahar Hussein,Amani Hashim,Reham El-Sharawy,Kristian Wende,Manuela Harms,Ulrike Lindequist 대한약학회 2012 Archives of Pharmacal Research Vol.35 No.5

        Chemical investigation on leaves of Annona muricata resulted in the isolation of the flavonol triglycoside, quercetin 3-O-α-rhamnosyl-(1'''' → 6'')-β-sophoroside, together with twelve known phenolics. The structures of these compounds were established by 1D- and 2D-nuclear magnetic resonance spectroscopic techniques and mass spectrometry data. The in vitro antioxidant studies of the investigated aqueous ethanol extract and its column fractions were accomplished using the oxygen radical absorbance capacity (ORAC) method. A stimulating effect on HaCaT human keratinocytes by the leaf extract was also assessed. Il-6 production after UV irradiation was not influenced by A. muricata leaf extract.

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