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On-line coupling of derivatization with pre-concentration to determine trace levels of methotrexate

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Journal of Pharmaceutical Analysis 2013年第1期3卷 28-35页

作者： Samy Emara Tsutomu Masujima Walaa Zarad maha Kamal Ramzia EL-Bagary Pharmaceutical Chemistry Department Faculty of PharmacyMisr International University Analytical Molecular Medicine and Devices Laboratory Hiroshima UniversityGraduate School of Biomedical Sciences Pharmaceutical Analytical Chemistry Department Faculty of PharmacyModern Sciences and Arts University Pharmaceutical Chemistry Department Faculty of PharmacyCairo University

A new simple, sensitive and precise green analytical procedure using an automated packed-reactor derivatization technique coupled with on-line solid-phase enrichment （SPEn） has been developed and evaluated to determine trace levels of methotrexate （MTX）. The method was based on injection of MTX into a flowing stream of phosphate buffer （0.04 M, ptt 3.4）, carried through the packed oxidant reactor of Cerium （IV） trihydroxyhydroperoxide for oxidative cleavage of the drug into highly fluorescent product, 2,4-diaminopteridine- 6-carboxylic acid, followed by SPEn on a head of short ODS column （10mm x 4.6 mm i.d., 5 I＋tm particle size）. The flow rate was 0.25 mL/min and packed reactor temperaturc was 40 ~C. The trapped product was back-flush eluted from the ODS column to the detector by column-switching with an environmentally friendly mobile phase consisting of ethanol and phosphate buffer （0.04 M, pH 3.4） in the ratio of 5：95 （v/v）. The eluent was monitored at emission and excitation wavelengths of 460 and was linear over the concentration range of 1.25-50 360 nm, respectively. The calibration curve ng/mL with a detection limit of 0.08 ug/ml..The method was successfully applied to determine MTX in pharmaceutical formulations with mean percentage recovery ranging from 99.48 to 99.60.

关键词： Methotrexate Flow injection analysis Cerium (IV) trihydroxy-hydroperoxide On-line solid-phaseenrichment Fluorescence detection

Electrochemical hydrogen compression and purification versus competing technologies: Part Ⅰ. Pros and cons

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Chinese Journal of Catalysis 2020年第5期41卷 756-769页

作者： maha Rhandi Marine Trégaro Florence Druart Jonathan Deseure Marian Chatenet Univ.Savoie Mont Blanc CNRSGrenoble-INPLEPMI38000 GrenobleFrance

It is undisputed that hydrogen will play a great role in our future energetic mix, because it enables the storage of renewable electricity(power-to-H2) and the reversible conversion into electricity in fuel cell, not to speak of its wide use in the(petro)chemical industry. Whereas in these applications, pure hydrogen is required, today’s hydrogen production is still largely based on fossil fuels and can therefore not be considered pure. Therefore, purification of hydrogen is mandatory, at a large scale. In addition, hydrogen being the lightest gas, its volumetric energy content is well-below its competing fuels, unless it is compressed at high pressures(typically 70 MPa), making compression unavoidable as well. This contribution will detail the means available today for both purification and for compression of hydrogen. It will show that among the available technologies, the electrochemical hydrogen compressor(EHC), which also enables hydrogen purification, has numerous advantages compared to the classical technologies currently used at the industrial scale. EHC has their thermodynamic and operational advantages, but also their ease of use. However, the deployment of EHCs will be viable only if they reach sufficient performances, which implies some specifications that their base materials should stick to. The present contribution will detail these specifications.

关键词： Electrochemical hydrogen compression Hydrogen energy Electrochemical hydrogen purification Thermdynamics Efficiency

Electrochemical hydrogen compression and purification versus competing technologies: Part Ⅱ. Challenges in electrocatalysis

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Chinese Journal of Catalysis 2020年第5期41卷 770-782页

作者： Marine Trégaro maha Rhandi Florence Druart Jonathan Deseure Marian Chatenet Univ.Grenoble Alpes Univ.Savoie Mont BlancCNRSGrenoble-INPLEPMI38000 GrenobleFrance

Hydrogen will be at the basis of the World’s energy policy in forthcoming decades, owing to its decarbonized nature, at least when produced from renewables. For now, hydrogen is still essentially produced from fossil feedstock(and to a minor extent from biomass);in consequence the present hydrogen gas on the market is containing non-negligible amounts of impurities that prevent its immediate usage in specialty chemistry or as an energy carrier in fuel cells, e.g. in transportation applications(cars, buses, trains, boats, etc.) that gradually spread on the planet. For these purposes, hydrogen must be of sufficient purity but also sufficiently compressed(at high pressures, typically 70 MPa), rendering purification and compression steps unavoidable in the hydrogen cycle. As shown in the first part of this contribution "Electrochemical hydrogen compression and purification versus competing technologies: Part I. pros and cons", electrochemical hydrogen compressors(EHCs), which enable both hydrogen purification and compression, exhibit many theoretical(thermodynamic) and practical(kinetics) advantages over their mechanical counterparts. However, in order to be competitive, EHCs must operate in very intensive conditions(high current density and low cell voltage) that can only be reached if their core materials, e.g. the membrane and the electrodes/electrocatalysts, are optimized. This contribution will particularly focus on the properties electrocatalysts must exhibit to be used in EHCs: they shall promote(very) fast hydrogen oxidation reaction(HOR) in presence of impurities, which implies that they are(very) tolerant to poisons as well. This consists of a prerequisite for the operation of the anode of an EHC used for the purification-compression of hydrogen, and the materials developed for poison-tolerance in the vast literature on low-temperature fuel cells, may not always satisfy these two criteria, as this contribution will review.

关键词： Electrochemical hydrogen compression Electrochemical hydrogen purification Electrocatalysts Hydrogen oxidation Poison tolerance

Multivariate Aggregated NOMA for Resource Aware Wireless Network Communication Security

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Computers, Materials & Continua 2023年第1期74卷 1693-1708页

作者： V.Sridhar K.V.Ranga Rao Saddam Hussain Syed Sajid Ullah Roobaea Alroobaea maha Abdelhaq Raed Alsaqour ECE Department Vidya Jyothi Institute of TechnologyIndia CSE Department Neil Gogte Institute of TechnologyIndia School of Digital Science Universiti Brunei DarussalamJalanTungku LinkGadong BE1410Brunei Darussalam Department of Information and Communication Technology University of Agder(UiA)N-4898 GrimstadNorway Department of Computer Science College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Information Technology College of Computer and Information SciencesPrincess Nourahbint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Department of Information Technology College of Computing and InformaticsSaudi Electronic University93499RiyadhSaudi Arabia

NonorthogonalMultiple Access(NOMA)is incorporated into the wireless network systems to achieve better connectivity,spectral and energy effectiveness,higher data transfer rate,and also obtain the high quality of services(QoS).In order to improve throughput and minimum latency,aMultivariate Renkonen Regressive Weighted Preference Bootstrap Aggregation based Nonorthogonal Multiple Access(MRRWPBA-NOMA)technique is introduced for network *** the downlink transmission,each mobile device’s resources and their characteristics like energy,bandwidth,and trust are *** by,the Weighted Preference Bootstrap Aggregation is applied to recognize the resource-efficient mobile devices for aware data transmission by constructing the different weak hypotheses i.e.,Multivariate Renkonen Regression *** on the classification,resource and trust-aware devices are selected for *** of the proposed MRRWPBA-NOMA technique and existing methods are carried out with different metrics such as data delivery ratio,throughput,latency,packet loss rate,and energy efficiency,signaling *** simulation results assessment indicates that the proposed MRRWPBA-NOMA outperforms well than the conventional methods.

关键词： Mobile network multivariate renkonen regression weighted preference bootstrap aggregation resource-aware secure data communication NOMA

Optimized Deep Learning Model for Colorectal Cancer Detection and Classification Model

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Computers, Materials & Continua 2022年第6期71卷 5751-5764页

作者： Mahmoud Ragab Khalid Eljaaly maha Farouk SSabir Ehab Bahaudien Ashary S.M.Abo-Dahab E.M.Khalil Information Technology Department Faculty of Computing and Information TechnologyKing Abdulaziz UniversityJeddah21589Saudi Arabia Center of Artificial Intelligence for Precision Medicines King Abdulaziz UniversityJeddah21589Saudi Arabia Department of Mathematics Faculty of ScienceAl-Azhar UniversityNaser City11884CairoEgypt Department of Pharmacy Practice Faculty of PharmacyKing Abdulaziz UniversityJeddah21589Saudi Arabia Information Systems Department Faculty of Computing and Information TechnologyKing Abdulaziz UniversityJeddah21589Saudi Arabia Electrical and Computer Engineering Department Faculty of EngineeringKing Abdulaziz UniversityJeddah21589Saudi Arabia Computer Science Department Faculty of Computers and InformationLuxor University85951Egypt Mathematics Department Faculty of ScienceSouth Valley UniversityQena83523Egypt Department of Mathematics Faculty of ScienceTaif UniversityTaif21944Saudi Arabia

The recent developments in biological and information technologies have resulted in the generation of massive quantities of data it speeds up the process of knowledge discovery from biological *** to the advancements of medical imaging in healthcare decision making,significant attention has been paid by the computer vision and deep learning(DL)*** the same time,the detection and classification of colorectal cancer(CC)become essential to reduce the severity of the disease at an earlier *** existing methods are commonly based on the combination of textual features to examine the classifier results or machine learning(ML)to recognize the existence of *** this aspect,this study focuses on the design of intelligent DL based CC detection and classification(IDL-CCDC)model for bioinformatics *** proposed IDL-CCDC technique aims to detect and classify different classes of *** addition,the IDLCCDC technique involves fuzzy filtering technique for noise removal ***,water wave optimization(WWO)based EfficientNet model is employed for feature extraction ***,chaotic glowworm swarm optimization(CGSO)based variational auto encoder(VAE)is applied for the classification of CC into benign or *** design of WWO and CGSO algorithms helps to increase the overall classification *** performance validation of the IDL-CCDC technique takes place using benchmark Warwick-QU dataset and the results portrayed the supremacy of the IDL-CCDC technique over the recent approaches with the maximum accuracy of 0.969.

关键词： Colorectal cancer deep learning medical imaging bioinformatics metaheuristics parameter tuning

Nuclear Reaction Models for Systematic Analysis of the Fast Neutron Induced （n, p）, （n, a） Nuclear Reaction for Some Stable Nuclide

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材料科学与工程（中英文A版） 2011年第2X期1卷 272-292页

作者： maha Torj man Department of Physics Faculty of science Albaath University Syria

Venous thromboembolism prophylaxis-prescribing patterns among elderly medical patients in a Saudi tertiary care center:success or failure?

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Journal of Geriatric Cardiology 2020年第12期17卷 775-781页

作者： Dalal A.Alabdulkarim Omar A.Almohammed maha A.Al Ammari Nada S.Almaklafi Munirah A.Alkathiri Manal A.Aljohani Pharmaceutical Care Service Ministry of the National Guard-Health AffairsRiyadhSaudi Arabia King Abdullah International Medical Research Center RiyadhSaudi Arabia Department of Clinical Pharmacy College of PharmacyKing Saud UniversityRiyadhSaudi Arabia

Background Hospitalized elderly patients are at high risk of venous thromboembolism(VTE),and the appropriate use of thromboprophylaxis can significantly reduce the incidence of VTE in high-risk *** investigated the pattern of VTE prophylaxis administration among elderly medical patients and assessed its appropriateness based on the American College of Chest Physicians(ACCP)*** A cross-sectional single-center study was conducted between October 2019 and March 2020,including hospitalized(>48 h),elderly(≥60 years),medical patients,and excluding patients receiving anticoagulant for other reason,having contraindication to thromboprophylaxis,or had VTE diagnosed within 48 *** Padua prediction score was used to determine the patients’risk for VTE,and thromboprophylaxis use was assessed against the ACCP *** The study included 396 patients with an average age of 75.0±9.01 years,and most patients(71.7%)were classified as high risk for VTE development(Padua score≥4 points).Thromboprophylaxis use was inappropriate in 27.3%of patients,of whom 85.2%were ineligible but still received *** who were classified as low risk of VTE were more likely to receive inappropriate thromboprophylaxis(AOR=76.5,95%CI:16.1-363.2),whereas patients with acute infection or rheumatologic disorder were less likely to receive inappropriate thromboprophylaxis(AOR=0.46,95%CI:0.22-0.96).Conclusions Although the use of thromboprophylaxis among high-risk elderly patients was reasonably adequate,a large proportion of low-risk patients were exposed to unnecessary risk through inappropriate overutilization of ***,healthcare providers should accurately assess patients’risk before prescribing thromboprophylaxis to ensure patient safety.

关键词： Hemorrhage Hospitalization Prophylaxis The elderly Venous thromboembolism

Epidemiologic and Clinicopathologic Features of Advanced Hepatocellular Carcinoma

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Journal of Cancer Therapy 2019年第6期10卷 411-421页

作者： maha L. Zamzam Department of Clinical Oncology and Nuclear Medicine Faculty of Medicine Suez Canal University Ismailia Egypt

Background: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide as well as in Egypt where it constitutes a significant public health problem. HCC is the third most common cause of death from cancer and chronic infection with HBV and HCV are the most important precursors for HCC development. Objective: To study the epidemiologic, clinical and pathological features of advanced HCC in clinical oncology and Nuclear medicine department, Suez Canal University hospital. Method: This is a retrospective study done to analyse the clinical, demographic and pathological data of advanced HCC patients that attended clinical oncology and Nuclear Medicine Department, Suez Canal University Hospital in the period between January 2013 and December 2016. Results: Results revealed that mean age of the patients was 60.2 ± 7.69, 71.74% male and 28.26% Female, 91.3% were HCV positive while 6.5% were HBV positive. Liver cirrhosis was in 89.13% of patients. Majority of the patients (78.2%) were child Pugh Score B and 21.7% were child Pugh Score C. 67.39% of patients had diabetes. Portal vein thrombosis was present in 50% of cases. Alpha fetoprotein was elevated >400 in 56.52% of cases. Thirty four patients received treatment in the form of chemotherapy while 12 patients did not receive treatment. There is a highly significant increase in survival time P 0.001 in treated group compared to untreated group. Median survival time (in months) was five months in the treated group versus one month in the untreated group. Conclusion: HCC is one of the increasing major health problems in both developing and developed countries. The most important risk factor is cirrhosis which is mainly due to HCV infection. Thus, much effort should be put into the field of prevention and treatment of viral hepatitis infections and chronic liver disease. Screening programs should be done to get rid of the problem, and most importantly, there must be an acceptable and effective therapy f

关键词： Hepatocellular Carcinoma Epidemiologic Clinicopathologic Survival

Value of duplex doppler ultrasonography in non-invasive assessment of children with chronic liver disease

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World Journal of Gastroenterology 2010年第48期16卷 6139-6144页

作者： Mortada HF El-Shabrawi Maissa El-Raziky maha Sheiba Hanaa M El-Karaksy Mona El-Raziky Fetouh Hassanin Abeer Ramadan Department of Pediatrics Cairo University Department of Tropical Medicine Cairo University Department of Clinical Pharmacy Misr International University

AIM:To investigate the value of duplex Doppler ultrasonography (US) in the assessment of the hemodynamics of the portal and hepatic veins in a cohort of children with chronic liver disease (CLD) and to detect any relationship between the US changes,etiology and severity (or stage) of CLD. METHODS:We prospectively enrolled 25 children with biopsy-proven CLD. Thirteen had cirrhosis (aged 8.9 ± 2.0 years) and 12 had chronic hepatitis (aged 9.3 ± 2.3 years). Gray scale and color-coded duplex Doppler US were performed for all,as well as 30 healthy age and sex-matched controls. Findings were correlated with clinical,laboratory and histopathological characteristics. RESULTS:Prominent caudate lobe was detected in 100% of cirrhotics,but none of the chronic hepatitis or controls. Thickened lesser omentum and loss of the triphasic waveform of the hepatic vein were present in 69.2% and 53.8% of cirrhotics vs 33.3% and 8.3% of chronic hepatitis respectively. Portal vein flow velocity was significantly lower (P < 0.0001) and the congestion index was significantly higher (P < 0.005) in both patient groups compared to controls. Child-Pugh's staging showed a positive correlation with both abnormal hepatic vein waveform and direction of portal blood flow; and a negative correlation with both hepatic and portal vein flow velocities. No correlation with the etiology of CLD could be detected. CONCLUSION:Duplex Doppler added to grayscale US can detect significant morphologic and portal hemodynamic changes that correlate with the severity (stage) of CLD,but not with etiology.

关键词： Chronic hepatitis Chronic liver disease Cirrhosis Doppler Grayscale Pediatrics Ultrasound