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Investigation of Extracts from Tunisian Ethnomedicinal Plants as Antioxidants,Cytotoxins,and Antimicrobials

Biomedical and Environmental Sciences 2017年第11期30卷 811-824页

作者： guesmi fatma Ben Hadj Ahmed Sami Landoulsi Ahmed Laboratory of Biochemistry and Molecular Biology Faculty of Sciences of BizerteUniversity of CarthageZarzouna 7021Tunisia Laboratory of Protein Engineering and Bioactive Molecules(LIP-MB) National Institute of Applied Sciences and Technology(INSA T)BP 6761080 Tunis CedexTunisia

Objective To determine the medicinal potential of various plants and their parts extracted with different solvents. Methods The total phenolic content of acetonitrile/water（60%-40%）（ACN/W） and aqueous（W） extract fractions was determined by high-performance liquid chromatography（HPLC）, and terpenic compounds were detected by gas chromatography/mass spectrometry（GC/MS）. Antioxidant activity of the samples was evaluated using 2,2-diphenyl-1-picrylhydrazyl（DPPH） assay and β-carotene bleaching method. Cell viability was investigated by thiazolyl blue tetrazolium bromide [3-（4,5-dimethylthiazol）-2-yl 2,5-diphenyltetrazolium bromide]（MTT） assay. The mechanisms involved in cytotoxic activity were investigated in a murine macrophage cell line（RAW 264.7） and cancer lines. Results Our findings show that 11 plant species exhibited biological activity. In addition, moderate antibacterial activity was reported against one or more of the tested bacterial strains at two concentrations： 300 μg and 3 mg/disc. Furthermore, our data reveal that among all plants investigated, some extract and hydrophobic fractions were potent scavengers of the DPPH radical（6.78 μg/m L 〈 EC50 〈 8.55 μg/mL）. Taken together, our results show that Nerium oleander（NOACN/W） and Pituranthos tortuosus（PTACN/W） were highly cytotoxic against RAW 264.7 cells with IC80 values of 0.36, and 1.55 μg/mL, respectively. In contrast, murine macrophage cell lines had low growth and were significantly sensitive to water extracts of Thymus hirtus sp. algeriensis（THW）, Lavandula multifida（LMW）, and ACN/W extract of Erica multiflora（EMACN/W） at doses 〉 400, 47.20, and 116.74 μg/m L, respectively. The current work demonstrates that RAW 264.7 cell proliferation was inhibited by samples in a dose-dependent manner. Conclusion Our findings, validated through free radical scavenging activity, agar diffusion assay, and cytotoxicity of essential oils towards cancer cells, show that ethnomedicinal plants used in this work have a novel

关键词： Phenolic compounds Cytotoxicity Antioxidant Antibacterial

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Antioxidant Machinery Related to Decreased MDA Generation by Thymus Algeriensis Essential Oil-induced Liver and Kidney Regeneration

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Biomedical and Environmental Sciences 2016年第9期29卷 639-649页

作者： guesmi fatma Amit K Tyagi Bellamine Houda Landoulsi Ahmed Laboratory of Biochemistry and Molecular Biology Faculty of Sciences of Bizerte University of Carthage 1054 Tunisia Department of Experimental Therapeutics The University of Texas M. D. Anderson Cancer Center 1515 Holcombe Boulevard Houston TX 77030 USA Service of Anatomo-Pathology of Menzel Bourguiba Bizerte 1054 Tunisia

Objective This study was conducted to determine the histopathological and biochemical effects of Thymus algeriensis essential oil （TEO） on hydrogen peroxide （H2O2）-induced oxidative stress in liver and kidney tissues of rats. Methods Rats were treated in six groups and were exposed for 2 weeks to low （LD; 100 μmol/L） and high doses （HD; 1 mmol/L） of H2O2 in the presence or absence of TEO （180 mg/kg）. Liver and kidney atrophy was measured by using biochemical and histopathological assays. Results Our study demonstrated that H2O2 induced liver and kidney atrophy, as evidenced by the significant elevation of serum aminotransferase, urea, and creatinine levels compared with those in the control rats. Urea levels were estimated by evaluating the activity of serum urease that hydrolyzes urea into CO2 and ammonia. However, TEO treatment significantly alleviated oxidative stress in the H2O2-induced liver and kidney toxicity model by reducing the levels of malondialdehyde concomitantly with marked elevations in superoxide dismutase, catalase, glutathione peroxidase, and glutathione S-transferase, as well as decrease in glutathione activity. Conclusion Our data demonstrated that TEO protected against H202 toxicity by decreasing oxidant levels and DNA damage, as well as increasing antioxidant levels, indicating that TEO has a spectrum of antioxidant and DNA-protective properties.

关键词： Liver and kidney atrophy Hydrogen peroxide Thymus algeriensis Antioxidants Toxicity

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Antioxidant Potential of Four Species of Natural Product and Therapeutic Strategies for Cancer through Suppression of Viability in the Human Multiple Myeloma Cell Line U266

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Biomedical and Environmental Sciences 2019年第1期32卷 22-33页

作者： guesmi fatma Saidi Issam Soussi Rawya Hfaiedh Najla Landoulsi Ahmed Laboratory of Biochemistry and Molecular Biology Faculty of Sciences of Bizerte University of Carthage Research Unit of Macromolecular Biochemistry and Genetics Faculty of Sciences of Gfasa Laboratory of Animal Eco Physiology Faculty of Sciences of Gafsa Laboratory of Integrated Physiology Faculty of Science of Bizerte University of Carthage

Objective This research aimed to evaluate the protective effects of bioactive compounds such as phenolic acids, flavonoids, and tannins present in four species extracted with methanol. Methods The total phenolic content of the methanolic extracts was measured spectrophotometrically. The effect of the extracts on cell viability in U266 cells was measured. The effects of extracts on free radical scavenging were assessed by the DPPH test and FRAP assay. Antibacterial effects of the natural products in this report were investigated by using the disc diffusion method. Results Our results clearly demonstrated that the methanolic extracts were characterized by a high amount of phenolic compounds. It has been speculated that ME-TA and ME-TAl exhibit a significant(P < 0.05) and dose-dependent antiradical potential. The exposure of cells to high doses of extracts almost completely suppressed cell growth in vitro. ME-TA and ME-TAl showed significant cytotoxic effects at a concentration of 100 μg/mL in the U266 cell line. ME-TAl and ME-CF inhibited the growth of B. subtilis and S. aureus, respectively, to the same extent as 10 μg/μL of chloramphenicol at a concentration of 1 mg/mL. Conclusion Overall, these results suggest that plants used in traditional medicine have a novel application as free radical scavengers, bacterial inhibitors and tumor suppressors.

关键词： Methanolic fractions Phenolic content DPPH FRAP U266 Antibacterial effect

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Prevention of H2O2 Induced Oxidative Damages of Rat Testis by Thymus algeriensis

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Biomedical and Environmental Sciences 2016年第4期29卷 275-285页

作者： fatma guesmi Hamida Beghalem Amit K Tyagi Manel Ben Ali Ramla Ben Mouhoub Houda Bellamine Ahmed Landoulsi Laboratory of Biochemistry and Molecular Biology Faculty of Sciences of Bizerte Zarzouma Bizerte 7021 Tunisia Cytokine Research Laboratory Department of Experimental Therapeutics The University of Texas M. D. Anderson Cancer Center 1515 Holcombe Boulevard Houston TX 77030 USA Laboratory of Biomonitoring of the Environment (LRO1/ES14) Faculty of Sciences of Bizerte Zarzouma Bizerte 7021 Tunisia Service of Anatomo-Pathology of Menzel Bourguiba Bizerte 7050 Tunisia

Objective We evaluate the effects of Thymus algeriensis （TEO） against hydrogen peroxide （H202） toxicity on body and testis weight, testis sperm count, testis lipid peroxidation, and antioxidant enzyme activities in rats. Methods Rats were treated with low （LD） and high dose （HD） of H202 （0.1 and 1 mmol/L） in the presence or absence of TEO （150 mg/kg）. Results The results exhibited a significant decrease in body weight and testis weight, in total sperm number decrease （P〈0.05）, sperm motility and percentage of sperm viability, leading to complete arrest, in sperm flagellar beat frequency by the gavage of 1 mmol/L H202 compared to controls. The administration of H2O2 resulted in a significant reduction in testis GSH, GPx, CAT, SOD, and GST activity and significant increase （P〈0.05） in MDA concentration compared with the untreated control animals. TEO pre-treatment protected testis from the H2O2 generated oxidative stress. These results were confirmed by histological architecture examinations. Conclusion H2O2 has the ability to alter the sperm function, characteristics and development of testis. However, TEO is an efficient natural agent, which can prevent the testis from H2O2-induced oxidative damage in rats.

关键词： Testis Hydrogen peroxide TEO Antioxidants Infertility

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Adsorption of F-, NO3-and SO42-on AFN Anionic Membrane: Kinetics and Thermodynamics Studies

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American Journal of Analytical Chemistry 2013年第9期4卷 501-509页

作者： Chiraz Hannachi fatma guesmi Wided Bouguerra Bèchir Hamrouni UR Traitement et Dessalement des Eaux Faculté des Sciences de Tunis Université de Tunis El Manar Manar II Tunisie

The sorption of and from aqueous solution on AFN membrane has been studied and the equilibrium isotherms determined. The experimental data have been analyzed using the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models at different temperatures varying from 283 to 313 K. The results were analyzed using three kinetic models, Lagergen first order, second order and the Elovich model. The obtained results show that the best-fit correlation of the experimental data was obtained using the second order model. Thermodynamic parameters for the adsorption system were determined at 283, 298 and 313 K.

关键词： AFN Membrane Adsorption Isotherm Kinetic Models Thermodynamics Parameters

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Ion Exchange Equilibrium between DOWEX 1X8 Resin Modified by Polyethyleneimine and Electrolyte Solutions

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Journal of Water Resource and Protection 2013年第11期5卷 1059-1065页

作者： Chiraz Hannachi fatma guesmi Khaoula Missaoui Hana Tounakti Béchir Hamrouni UR Traitement et Dessalement des Eaux Faculté des Sciences de Tunis Université de Tunis El Manar Manar II Tunisie

In order to improve the selectivity of anion exchange resin, the surface of gel type anion exchange resin was modified with polyethyleneimine (PEI). In the proposed work an attempt to the utilization of commercial anion exchange resin modified by adsorption of polyethyleneimine was investigated. Many conditions of modification of anion exchange resin surface were studied. The influent parameters on the DOWEX 1X8 resin modification were determined using a factorial experimental design. The ion exchange reactions were studied for modified and unmodified resin and electrolyte solutions containing Cl-,NO3-,SO42-. All experiments were performed at constant ionic strength I = 0.3 mol·L-1 and constant temperature T = 298 K. Ionic exchange isotherms were established for the binary systems:Cl-/NO3-,Cl-/SO42- and NO3-/SO42-. The obtained results show that nitrate ion was more sorbed than chloride and sulfate. The order of preference for the anions studied in this investigation is:NO3->Cl->SO42-. All the results given by this resin were compared with those obtained with the AMX anion exchange membrane. Selectivity coefficients and thermodynamic constants for the three binary systems and for the two resins were determined. The modified resin became more selective towards monovalent anions.

关键词： Resin Modification Polyethyleneimine Factorial Design Binary System Isotherm Selectivity Coefficient

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Nitrogen mineralization in the oldest climax communities in the eastern Mediterranean region

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Journal of Forestry Research 2024年第1期35卷 213-228页

作者： fatma Selcen Sakar Gürcan Güleryüz Department of Biology Section Ecology GörükleGraduate School of Natural and Applied ScienceUniversity of Bursa Uludağ16059 NilüferBursaTurkey Department of Biology Section Ecology GörükleFaculty of Science and ArtsUniversity of Bursa Uludağ16059 NilüferBursaTurkey

In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest *** the oldest pure communi-ties of Pinus nigra(PN),Fagus orientalis(FO),and Abies bornmuelleriana(AB)in the mountain range of Mount Uludağ,Bursa,Turkey,annual net yield and N mineraliza-tion in the 0-5-and 5-20-cm soil layers were determined in a field incubation study over 1 *** locations were chosen from 1300 to 1600 m a.s.l.,and moisture content(%),pH,water-holding capacity(%),organic C,total N,and C/N ratio,and annual net mineral N yield of the soil and hydro-lyzed tannic acid and total phenolic compounds in litter were compared for these forest *** had the highest annual net Nmin yield(43.9±4.8 kg ha^(-1) a^(-1)),*** the lowest(30.5±4.2 kg ha^(-1) a^(-1)).Our findings show that in the oldest forest ecosystems,the seasonal soil moisture content and tree species play an essential role in N cycling and that hydrolyzed tannic acids and total phenolic compounds effectively control N *** acid and total phenolics in the litter were found to inhibit nitrification,but total phenolics were found to stimulate ammonification.

关键词： Oldest forest communities Nitrogen mineralization Nitrification Tannic acid Total phenolic Litter

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Exploring Sequential Feature Selection in Deep Bi-LSTM Models for Speech Emotion Recognition

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Computers, Materials & Continua 2024年第2期78卷 2689-2719页

作者： fatma Harby Mansor Alohali Adel Thaljaoui Amira Samy Talaat Computer Science Department Future Academy-Higher Future Institute for Specialized Technological StudiesCairo12622Egypt Department of Computer Science and Information College of Science at Zulfi Majmaah UniversityP.O.Box 66Al-Majmaah11952Saudi Arabia Preparatory Institute for Engineering Studies of Gafsa ZarrougGafsa2112Tunisia Computers and Systems Department Electronics Research InstituteCairo12622Egypt

Machine Learning(ML)algorithms play a pivotal role in Speech Emotion Recognition(SER),although they encounter a formidable obstacle in accurately discerning a speaker’s emotional *** examination of the emotional states of speakers holds significant importance in a range of real-time applications,including but not limited to virtual reality,human-robot interaction,emergency centers,and human behavior *** identifying emotions in the SER process relies on extracting relevant information from audio *** studies on SER have predominantly utilized short-time characteristics such as Mel Frequency Cepstral Coefficients(MFCCs)due to their ability to capture the periodic nature of audio signals *** these traits may improve their ability to perceive and interpret emotional depictions appropriately,MFCCS has some *** this study aims to tackle the aforementioned issue by systematically picking multiple audio cues,enhancing the classifier model’s efficacy in accurately discerning human *** utilized dataset is taken from the EMO-DB database,preprocessing input speech is done using a 2D Convolution Neural Network(CNN)involves applying convolutional operations to spectrograms as they afford a visual representation of the way the audio signal frequency content changes over *** next step is the spectrogram data normalization which is crucial for Neural Network(NN)training as it aids in faster *** the five auditory features MFCCs,Chroma,Mel-Spectrogram,Contrast,and Tonnetz are extracted from the spectrogram *** attitude of feature selection is to retain only dominant features by excluding the irrelevant *** this paper,the Sequential Forward Selection(SFS)and Sequential Backward Selection(SBS)techniques were employed for multiple audio cues features ***,the feature sets composed from the hybrid feature extraction methods are fed into the deep Bidirectional Long Short

关键词： Artificial intelligence application multi features sequential selection speech emotion recognition deep Bi-LSTM

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Time-varying nexus and causality in the quantile between Google investor sentiment and cryptocurrency returns

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Blockchain(Research and Applications) 2024年第2期5卷 1-12页

作者： fatma Ben Hamadou Taicir Mezghani Mouna Boujelbene Abbes Faculty of Economics and Management of Sfax Laboratory URECASfax UniversityBP1169.3029SfaxTunisia

Understanding the interplay between investor sentiment and cryptocurrency returns has become a critical area of ***,this study aims to uncover the role of Google investor sentiment on cryptocurrency returns(including Bitcoin,Litecoin,Ethereum,and Tether),especially during the 2017-18 bubble(January 01,2017,to December 31,2018)and the COVID-19 pandemic(January 01,2020,to March 15,2022).To achieve this,we use two techniques:quantile causality and wavelet ***,the quantile causality test revealed that investors’optimistic sentiments have notably higher cryptocurrency returns,whereas pessimistic sentiments have significantly opposite ***,the wavelet coherence analysis shows that co-movement between investor sentiment and Tether cannot be considered *** result supports the role of Tether as a stablecoin in portfolio diversification *** fact,the findings will help investors improve the accuracy of cryptocurrency return forecasts in times of stressful events and pave the way for enhanced decision-making utility.

关键词： Cryptocurrency COVID-19 pandemic Wavelet coherence Causality-in-quantile approach Google trends

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A survey on automatic dashboard recommendation systems

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Visual Informatics 2024年第1期8卷 67-79页

作者： Praveen Soni Cyril de Runz fatma Bouali Gilles Venturini LIFAT University of Tours64 avenue Jean PortalisTours37200France IUT C University of Lille53 Rue de l’AlmaRoubaix59100France

This paper presents a survey on automatic or semi-automatic recommendation systems that help users create *** starts by showing the important role that dashboards play in data science,and gives an informal definition of dashboards,i.e.,a set of visualizations possibly with linkage,a screen layout and user *** are mainly interested in systems that use a fully or partially automatic mechanism to recommend dashboards to *** automation includes the suggestion of data and visualizations,the optimization of the layout and the use of user *** position our work with respect to existing *** from a set of over 1000 papers,we have selected and analyzed 19 papers/systems along several *** main dimensions were the set of considered visualizations,the suggestion method,the utility/objective functions,the layout,and the user *** conclude by highlighting the main achievements in this domain and by proposing perspectives.

关键词： Automatic visualization Dashboard recommendation Multiple view interfaces

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