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The Ciliate Protist <i>Tetrahymena pyriformis</i>as a Cellular Adhesion Model for the Pathogenic Bacterium <i>Staphylococcus aureus</i>

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Advances in Bioscience and Biotechnology 2017年第12期8卷 491-507页

作者： bouchra el khalfi Mohammed Benlahfid Sofia Jarmouni Nezha Senhaji Aurelio Serrano Delgado Abdelaziz Soukri Laboratory of Physiopathology Genetics Molecular and Biotechnology (PGMB) Faculty of Sciences Ain Chock Research Center: Health & Biotechnology University Hassan II of Casablanca Casablanca Morocco Laboratory of Genetic and Molecular Pathology (LGPM) Medical School Hassan II University Casablanca Morocco Institute of Biochemistry Vegetal and Photosynthesis (IBVF-CSIC University of Seville) Seville Spain

Staphylococcus aureus is one of the main pathogenic agents responsible for nosocomial and community-acquired bacterial infections. The pathogenicity of this Gram-positive bacterium is ensured by its different adhesion factors. Collagen and the extracellular glycoprotein adhesin are among the Staphylococcus most important virulence factors. It has been shown that most of the S. aureus strains carry the ica operon, responsible for biofilm production. However, the coexpression of the icaA and the icaD genes is necessary for complete biofilm synthesis. The aim of our study was to study a collection of 15 clinical strains of S. aureus from different sources for the presence of can and icaD genes coding intercellular adhesion proteins. We also intended to estimate the strains’ ability to form biofilms by the red Cong method and to test the adhesion ability of S. aureus to the ciliated protist Tetrahymena pyriformis, which we used as a novel cellular adhesion model. Finally, we checked the adhesion’s inhibition capacity of some plants extracts. The molecular detection of adhesion genes revealed that 80% of strains are cna positive, and 73% are icaD positive. Qualitative biofilm production of S. aureus revealed that 66.6% of strains were slime producers. The adhesion test revealed that 20% of strains are strongly adhering to T. pyriformis and that the Clematis cirrhosa extract has an anti-adhering effect of S. aureus to the ciliate T. pyriformis.

关键词： Staphylococcus aureus Adhering Genes (can and icaD) Tetrahymena pyriformis Biofilm Production Plant Extract Anti-Adhesion Effect

Qualitative analysis and simulation of a nonlinear integro-differential system modeling tumor-immune cells competition

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International Journal of Biomathematics 2018年第8期11卷 171-190页

作者： bouchra Aylaj Departement de Mathematiques et Informatique Faculte des Sciences Ain Chock Km 8 Route d'El adida B.P. 5366 Maarif 20100 Casablanca 20000 Maro

This paper deals with a qualitative and computational study of a class of integrodifferential model, with a nonlinear growth rate. The model is applied to immunology problems, in particular to the competition between tumors and immune system. Our purpose is to take into account the activity transfer processes bet ween cells. The first part of this paper deals with the modeling, while the second part develops the existence and uniqueness of global solutions to the initial boundary value problem related to the application of the model. Finally, numerical simulations are used to illustrate the results obtained for a dynamic of tumor cells contrasted by the immune system.

关键词： Population dynamics kinetic theory nonlinear semigroup separable equations immune competition quasilinear cauchy problem global solution integrodifferentialequations simulation

Cell Stress by Phosphate of Two Protozoa Tetrahymena thermophila and Tetrahymena pyriformis

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Advances in Bioscience and Biotechnology 2017年第12期8卷 451-462页

作者： Papa Daouda Mar bouchra el khalfi Jose Roman Perez-Castineira Aurelio Serrano Abdelaziz Soukri Laboratory of Physiopathology Genetics Molecular and Biotechnology(PGMB)Faculty of Sciences Ain ChockUniversity Hassan Ⅱ of CasablancaCasablancaMorocco Instituto de Bioquímica Vegetal y Fotosíntesis CSIC-Universidad de SevillaCentro de Investigaciones Científicas“Isla de la Cartuja”SevillaSpain

Phosphorus is one of the bioelements most needed as a compound cell by living organisms. Phosphorus is involved in several pathologies: in human with bone and kidney diseases, in mammals with metabolism disorder (glucose, insulin···), in microorganisms whose phosphorus is involved in cell growth. Phosphorus has various forms including pyrophosphate, a by-product of multiple pathways of biosynthesis. Enzymes that hydrolyze pyrophosphate are called inorganic pyrophosphatases (PPases). Two major types of inorganic pyrophosphatases are distinguished: the soluble pyrophosphatases (sPPases) and the membrane pyrophosphatases (mPPases or H+/Na+-PPases). They play a key role in the control of intracellular inorganic pyrophosphate level and produce an important ions gradient (H+ or Na+) to the cells. In this work, we primarily focused on the physiological study in a phosphate-poor medium of two models Tetrahymena thermophile and Tetrahymena pyriformis, following the mobility, the growth and the morphology of cells. Secondly, we evaluated the enzymatic activity of soluble and membrane pyrophosphatases in both species grown in the same complex medium. A decrease of cell growth is correlated with unusual morphologies and different mobility in the stress medium. The measurement of soluble and membrane inorganic pyrophosphatases activities also shows a decrease which illustrates the lack of phosphate found in the stress medium. Deficiency of phosphate is a limiting factor for protozoan growth. These results indicate that Tetrahymena can be used as a model of cellular stress and consists of a target to study inorganic pyrophosphatases for a better understanding of phosphate cycle in higher organisms.

关键词： Phosphorus Pyrophosphatases NBRIP Tetrahymena

Multi-Objective Optimization Using Genetic Algorithms of Multi-Pass Turning Process

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Engineering（科研） 2013年第7期5卷 601-610页

作者： Abdelouahhab Jabri Abdellah el Barkany Ahmed el khalfi Faculty of Sciences and Technology Department of Mechanical Engineering Sidi Mohammed Ben Abdellah University Fez Morocco

In this paper we present a multi-optimization technique based on genetic algorithms to search optimal cuttings parameters such as cutting depth, feed rate and cutting speed of multi-pass turning processes. Tow objective functions are simultaneously optimized under a set of practical of machining constraints, the first objective function is cutting cost and the second one is the used tool life time. The proposed model deals multi-pass turning processes where the cutting operations are divided into multi-pass rough machining and finish machining. Results obtained from Genetic Algorithms method are presented in Pareto frontier graphic;this technique helps us in decision making process. An example is presented to illustrate the procedure of this technique.

关键词： Genetic Algorithms Mutli-Objective Optimization Turning Process Machining

A Maintenance Optimzation Policy for an electric Power Distribution System: Case of the HV/MV Substations

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Engineering（科研） 2014年第5期6卷 236-253页

作者： Morad Mahmoudi Abdellah el Barkany Ahmed el khalfi Department of Mechanical Engineering Faculty of Science and Technology Sidi Mohamed Ben Abdellah University Fez Morocco National Office of electricity and Water Supply (ONEE) Casablanca Morocco

Today, in the modern era, and under the pressure of rapid development around the kingdom regions, electric utilities are confronted with a myriad of challenges that include aging infrastructure, enhanced expectation of reliability, reduced cost, and coping effectively with uncertainties and changing regulation requirements. Indeed, for distribution systems, HV/MV substations represent a complex and critical physical asset that requires a careful evaluation of their maintenance practices aiming at more cost-effective tasks. The first concern of the electric power distribution company in Morocco is the optimization of the distribution network maintenance scheduling, to minimize system operating costs and ensure that the system is running most economically. There is significant pressure on power providers for greater system reliability and improvement of customer satisfaction, while similar emphasis is placed on cost reduction. These cost reductions focus on reducing operating and maintenance expenses, and minimizing investments in new plants and equipment. However, the present of the electricity distribution, influenced by a number of technical restrictions and strict regulatory requirements to meet, leads distribution utilities to search new ways of optimizing the maintenance management, make an effort to maximize profit by reducing their electricity supply and operation costs while maintaining their reliability, developing more effective activities, with lower costs. Furthermore, maximal HV/MV substation asset value and minimal maintenance cost are typical economic objectives of the electric utilities. The optimization of maintenance is one possible technique to reduce maintenance costs while improving reliability and utilities need to implement new strategies for more effective maintenance techniques and Asset Management (AM) methods programs to manage inspections and maintenance activities in order to control HV/MV substation equipment conditions. However, develop

关键词： HV/MV Distribution Substations Maintenance Strategy RCM Optimization Asset Management

Composing Specific Domains for Large Scale Systems

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通讯和计算机（中英文版） 2013年第6期10卷 844-856页

作者： Asmaa Baya bouchra el Asri Models and Systems Engineering team Mobile and Embedded Information Systems Laboratory ENS1AS Mohammed V SouissiUniversity Rabat 10000 Morocco

Selecting accurate post-elimination monitoring tools to prevent reemergence of urogenital schistosomiasis in Morocco:a pilot study

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Infectious Diseases of Poverty 2017年第1期6卷 664-672页

作者： Abdelaali Balahbib Fatima Amarir Paul L.A.M.Corstjens Claudia Jde Dood Govert Jvan Dam Amina Hajli Meryem Belhaddad bouchra el Mansouri Abderrahim Sadak Mohamed Rhajaouim el Bachir Adlaoui National Reference Laboratory for Schistosomiasis and Malacology National Institute of HygieneAgdalRabatMorocco Faculty of Science Laboratory of Zoology and General BiologyAgdalRabatMorocco Laboratory of Parasitology and Malacology Institute of Nursing Professions and Health TechniquesCasablancaMorocco Department of Molecular Cell Biology Leiden University Medical CenterLeidenThe Netherlands Department of Parasitology Leiden University Medical CenterLeidenThe Netherlands

Background:After alleged stop of transmission of schistosomiasis and further down the line in post elimination settings,sensitive tools are required to monitor infection status to prevent potential *** Rahala,where transmission cycle of Schistosoma haematobium is interrupted since 2004 but where 30%of snails are still infected by ***,potential human *** infection can’t be *** methods based on egg-counts do not provide the required sensitivity,antibody or antigen assays are envisaged as the most appropriate tools for this type of ***:In this pilot study,the performances of three assays were compared:two commercially available antibody tests(elISA and haemagglutination format)indicating exposure,and an antigen test(lateral flow strip format)demonstrating active *** 37 recruited study participants resided in Rahala(Akka,province Tata,Morocco).Participants had been diagnosed and cured from schistosomiasis in the period between 1983 and *** 2015 these asymptomatic participants provided fresh clinical samples(blood and urine)for analysis with the aforementioned diagnostics ***:No eggs were identified in the urine of the 37 *** haemagglutination test indicated 6 antibody positives whereas the elISA indicated 28 antibody positives,one indecisive and one false *** and haemagglutination results matched for 18 individuals,amongst which 5 out of 6 haemagglutination *** the antigen test(performed on paired serum and urine samples),serum from two participants(cured 21 and 32 years ago)indicated the presence of low levels of the highly specific Schistosoma circulating anodic antigen(CAA),demonstrating low worm level infections(less than 5 pg/ml corresponding to probably single worm pair).One tested also CAA positive with *** indicated the presence of human anti-Schistosoma antibodies in these two CAA positive cases,haemagglutination results were ***:To pre

关键词： Schistosomiasis Transmission stop elimination Monitoring Antibody test Antigen test Circulating Anodic Antigen(CAA) Active infection

Efficiency of combining pomegranate juice with low-doses of cisplatin and taxotere on A549 human lung adenocarcinoma cells

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Asian Pacific Journal of Tropical Biomedicine 2018年第1期8卷 19-24页

作者： Nasser Mohamad Hijazi Akram Sayed Ahmad bouchra Jamal Eddine Zeinab Ibrahim Sajida Rammal Hassan Al Rekaby Abd-el-Ameer Nasser Mouhamad Doctoral School of Science and Technology Research Platform for Environmental Science (PRASE) Lebanese University Université Fédérale de Toulouse Midi-Pyrénées INP-ENSIACET Laboratoire de Chimie Agro-industrielle Al Mustansiriya University College of Science Department of Biology American University of Beirut

Objective: To test the coalescence effect of two chemotherapy drugs at low effective dose(cisplatin and taxotere) combined with pomegranate juice on A549 cancer cells. Methods: Infrared spectroscopy method is a qualitative test that was performed to ensure the existence of the phytochemicals providing the antioxidant activity through the presence of the hydroxyl group(-OH). The viability of A549 cell line and normal MCs was tested using the neutral red uptake, Clonogenic survival, XTT and Cell migration assays. Results: Our results showed that this combination firstly led to a greater decrease in the viability of cells comparing to those treated with chemotherapy drugs alone, and secondly led to a significant reduction in cell migration. Conclusions: These data suggest a synergistic effect between the pomegranate and cisplatin which makes probably this combination a powerful option for treating lung adenocarcinoma and in parallel minimizing the systemic side effects.

关键词： Lung cancer Chemotherapy Cisplatin Taxotere Pomegranate A549 cells

Learning to Support Derivation of Adaptable Products in Software Product Lines

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Journal of Computer and Communications 2020年第4期8卷 114-126页

作者： Anissa Benlarabi Amal Khtira bouchra el Asri IMS Team ADMIR Laboratory Rabat IT Center ENSIAS Mohammed V University Rabat Morocco

Software product line engineering is a large scale development paradigm based on mass production. It consists in building a common platform from which a set of products can be derived. Under the constraints of continuous evolution and costs optimization, the derivation process must be able to answer customers’ requirements and provide adequate products in a short time without defects. However, this purpose cannot be achieved if the customer must wait for the change is implemented in the common platform. In this paper, we describe our work which proposes a framework to manage derivation of adaptable products. An adaptable product is obtained by deriving the most similar product from the common platform and changing it to support the new requirements. The aim of the framework is to give quick response to the customers need while the new requirements are being implemented in the common platform. The framework includes tools for processing natural language requirements, computing the similarity between products on the basis of their requirements, and the product adaptation effort measuring.

关键词： Software Product Lines Requirement Similarity Product Derivation Natural Language Processing Semantic Models