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Bioassay-guided isolation of novel and selective urease inhibitors from Diospyros lotus

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Chinese Journal of Natural Medicines 2017年第11期15卷 865-870页

作者： Abdur Rauf Ghias Uddin Bina S. Siddiqui Ajmal Khan Umar Farooq Farhan A. Khan syed majid bukhari Sher Bahadar Khan Department of Chemistry University ofSwabi Anbar-23561 Khyber Pakhtunkhwa Pakistan Institute of Chemical Sciences University ofPeshawar Peshawar-25120 Pakistan H.E.J. Research Institute of Chemistry International Center for Chemical and Biological Sciences University ofKarachL Ka- rachi- 75270 Pakistan Department of Chemistry COMSAT Institute of Information Technology Abbottabad-22060 Pakistan UoN Chair of Oman 's Medicinal Plants and Marine Natural Products University ofNizwa Birkat Al-Mouz Nizwa-616 Oman Center of Excellence for Advanced Materials Research (CEAMR) Department of Chemistry Faculty of Science King Abdulaziz University Jeddah 21589 Saudi Arabia Kingdom

Two new dimeric naphthoquinones, 5′,8′-dihydroxy-6,6′-dimethyl-7,3′-binaphthyl-1,4,1′,4′-tetraone(1; Di-naphthodiospyrol D) and 5′,8′-dihydroxy-5,8-dimethoxy-6,6′-dimethyl-7,3′-binaphthyl-1,4,1′,4′-tetraone(2; Di-naphthodiospyrol E), along with known naphthoquinones diospyrin(3) and 8-hydroxy diospyrin(4) were isolated from the chloroform fraction of extract of Diospyros lotus roots. Their structures were elucidated by advanced spectroscopic analyses, including HSQC, HMBC, NOESY, and J-resolved NMR experiments. The fractions and compounds 1-4 were evaluated for urease activity and phosphodiesterase-Ⅰ, carbonic anhydrase-Ⅱ and α-chymotrypsin enzyme inhibitory activities. Compounds 1 and 2 and their corresponding fractions showed significant and selective inhibitory effects on urease activities. The IC_(50) values of 1 and 2 were 260.4 ± 6.37 and 381.4 ± 4.80 μmol·L-1, respectively, using thiourea(IC_(50) = 21 ± 0.11 μmol·L^(-1)) as the standard inhibitor. This was the first report demonstrating that the naphthoquinones class showed urease inhibition.

关键词： Diospyros lotus Naphthoquinones Phosphodiesterase-Ⅰ Carbonic anhydrase-Ⅱ α-Chymotrypsin Urease inhibitory activities

Three new anthraquinone derivatives isolated from Symplocos racemosa and their antibiofilm activity

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Chinese Journal of Natural Medicines 2017年第12期15卷 944-949页

作者： Umar Farooq Sara Khan Sadia Naz Ajmal Khan Afsar Khan Ayaz Ahmed Abdur Rauf syed majid bukhari Shujaat Ali Khan Arfa Kamil Nadia Riaz Abdur Rahman Khan Department of Chemistry COMSATS Institute of Information Technology Abbottabad-22060 Pakistan Dr. Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological Sciences University of Karachi- 752 70 Pakistan Department of Geology University of Swabi Anbar-23430 KPK Pakistan Institute of Chemical Sciences University of Peshawar Peshawar 25120 Pakistan Department of Pharmaceutical Chemistry Faculty of Pharmacy Federal Urdu University of Arts Science and Technology Karachi Karachi 75300 Pakistan Department of Environmental Sciences COMSATS Institute of lnformation Technology Abbottabad-22060 Pakistan

Three new alkyl substituted anthraquinone derivatives, trivially named as symploquinones A-C(Compounds 1-3) were isolated from Symplocos racemosa. The structures of these compounds were determined on the basis of extensive spectroscopic analyses(UV, IR, Mass, ~1 H-and ^(13)C-NMR, and two-dimensional(2D) NMR techniques). The resulting data were also compared with the reported literature. These compounds were then subjected to antibacterial or antibiofilm testing. Compounds 1 and 3 exhibited good antibacterial activity in the concentration range of 160-83 μg·m L^(-1) against Streptococcus mutans, methicillin resistant Staphylococcus aureus and Proteus mirabilis. Both compounds were further screened for anti-biofilm activity, which revealed promising activities at sub-MIC concentrations. None of the compounds were found to be active against Klebsiella pneumoniae.

关键词： Symplocos racemosa Substituted anthraquinone Antibiofilm activity

Long-term outcomes of titanium-nitride-oxide coated stents and drug-eluting stents in acute coronary syndrome:A systematic review and meta-analysis

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World Journal of Cardiology 2024年第5期16卷 293-305页

作者： Muhammad Ahmed Ali Fahim Afia Salman Hira Anas Khan syed Muhammad Hasan Muskan FatimaBhojani Sarah Aslam Amna Zia Ul Haq Vishal Reddy Bejugam Beena Muntaha Nasir Wajiha Gul Abdul Moeed Abdelrahman S Abdalla Muhammad majid Muhammad Sohaib Asghar Md Al Hasibuzzaman Department of Internal Medicine Dow University of Health SciencesKarachi 74200Pakistan Department of Internal Medicine North Central Bronx HospitalBronxNY 10467United States Department of Urology Center for Academic MedicineStanford University School of MedicinePalo AltoCA 33872United States Department of Cardiovascular Imaging Cleveland ClinicClevelandOH 44195United States Division of Nephrology and Hypertension Mayo Clinic RochesterRochesterMN 55905United States Institute of Nutrition and Food Science University of DhakaDhaka 1000Bangladesh

BACKGROUND In severe cases of coronary artery disease,percutaneous coronary intervention provide promising *** stent used could be a drug-eluting stent(DES)or a titanium-nitride-oxide coated stent(TiNOS).AIM To compare the 5-year effectiveness and safety of the two stent *** The following systematic review and meta-analysis was conducted in accordance with the preferred reporting items for systematic reviews and meta-analysis guidelines,and PubMed/MEDLINE,Scopus,and Cochrane Central were searched from inception till August *** outcomes were major adverse cardiac events(MACE),cardiac death,myocardial infarction(MI),cardiac death or MI,and ischemia-driven total lesion revascularization(ID-TLR).RESULTS Four randomized controlled trials(RCT),which analyzed a sum total of 3045 patients with acute coronary syndrome(ACS)after a median follow-up time of 5 years were *** statistically insignificant,an increase in the ID-TLR was observed in patients receiving TiNOSs vs *** addition,MI,cardiac death and MI,and definite stent thrombosis(DST)were significantly decreased in the TiNOS *** analysis revealed no significant results with meta-regression presenting non-ST elevated MI(NSTEMI)as a statistically significant covariate in the outcome of *** TiNOS was found to be superior to DES in terms of MI,cardiac death or MI,and DST outcomes,however,the effect of the two stent types on ID-TLR and MACE was not significant.A greater number of studies are required to establish an accurate comparison of patient outcomes in TiNOS and DES.

关键词： Stents Drug-eluting Major adverse cardiac events All-cause death Meta-analysis

Classification of Positive COVID-19 CT Scans Using Deep Learning

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Computers, Materials & Continua 2021年第3期66卷 2923-2938页

作者： Muhammad Attique Khan Nazar Hussain Abdul majid Majed Alhaisoni syed Ahmad Chan bukhari Seifedine Kadry Yunyoung Nam Yu-Dong Zhang Department of Computer Science HITEC University TaxilaPakistan College of Computer Science and Engineering University of Ha’ilHa’ilSaudi Arabia Division of Computer Science Mathematics and ScienceCollins College of Professional StudiesSt.’John’s UniversityNew YorkUSA Department of Mathematics and Computer Science Beirut Arab UniversityLebanon Department of Computer Science and Engineering Soonchunhyang UniversityAsanSouth Korea Department of Informatics University of LeicesterLeicesterUK

In medical imaging,computer vision researchers are faced with a variety of features for verifying the authenticity of classifiers for an accurate *** response to the coronavirus 2019(COVID-19)pandemic,new testing procedures,medical treatments,and vaccines are being developed *** potential diagnostic tool is a reverse-transcription polymerase chain reaction(RT-PCR).RT-PCR,typically a time-consuming process,was less sensitive to COVID-19 recognition in the disease’s early *** we introduce an optimized deep learning(DL)scheme to distinguish COVID-19-infected patients from normal patients according to computed tomography(CT)*** the proposed method,contrast enhancement is used to improve the quality of the original images.A pretrained DenseNet-201 DL model is then trained using transfer *** fully connected layers and an average pool are used for feature *** extracted deep features are then optimized with a Firefly algorithm to select the most optimal learning *** the selected features is important to improving the accuracy of the approach;however,it directly affects the computational cost of the *** the proposed method,a new parallel high index technique is used to fuse two optimal vectors;the outcome is then passed on to an extreme learning machine for final *** were conducted on a collected database of patients using a 70:30 training:Testing *** results indicated an average classification accuracy of 94.76%with the proposed approach.A comparison of the outcomes to several other DL models demonstrated the effectiveness of our DL method for classifying COVID-19 based on CT scans.

关键词： Coronavirus contrast enhancement deep learning features optimization fusion classification

Preconcentration and Determination of Chromium Species Using Octadecyl Silica Membrane Disks and Flame Atomic Absorption Spectrometry

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Chinese Journal of Chemistry 2007年第12期25卷 1859-1865页

作者： MOGHIMI, Ali SABER-TEHRANI, Mohammad WAQIF-HUSAIN, syed MOHAMMADHOSSEINI, majid Department of Chemistry Islamic Azad University Varamin Campus Varamin Iran Department of Chem stry Faculty of Scence Scence and Research Campus lslamic Azad Universty Tehran Iran Department of Chemistry Islamic Azad University of Shahrood Shahrood Iran

A novel and selective method for the fast determination of trace amounts of chromium species in water samples has been developed. The procedure is based on the selective formation of chromium diethyldithiocarbamate complexes at different pH in the presence of Mn（Ⅱ） as an enhancement agent of chromium signals followed by elution with organic eluents and determination by atomic flame absorption spectrometry. The maximum capacity of the employed disks was found to be （396±3） pg and （376±2） pg for Cr（Ⅲ） and Cr（Ⅵ）, respectively. The detection limit of the proposed method is 49 and 43 ng·L^-1 for Cr（Ⅲ） and Cr（Ⅵ）, respectively. The proposed method was successfully applied for determination of chromium species Cr（Ⅲ） and Cr（Ⅵ） in different water samples.

关键词： solid phase extraction sodium diethyldithiocarbamate flame atomic absorption spectrometry octadecyl silica membrane disk

Effective link quality estimation as a means to improved end-to-end packet delivery in high traffic mobile ad hoc networks

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Digital Communications and Networks 2017年第3期3卷 150-163页

作者： syed Rehan Afzal Sander Stuijk majid Nabi Twan Basten Eindhoven University of Technology Den Dolech 2 5612AZ Eindhoven The Netherlands TNO-ESI Embedded Systems Innovation De Rondom 1 5612AP Eindhoven The Netherlands

Accurate link quality estimation is a fundamental building block in quality aware multi hop routing. In an inherently lossy, unreliable and dynamic medium such as wireless, the task of accurate estimation becomes very challenging. Over the years ETX has been widely used as a reliable link quality estimation metric. However, more recently it has been established that under heavy traffic loads ETX performance gets significantly worse. We examine the ETX metric＇s behavior in detail with respect to the MAC layer and UDP data; and identify the causes of its unreliability. Motivated by the observations made in our analysis, we present the design and implementation of our link quality measurement metric xDDR - a variation of ETX. This article extends xDDR to support network mobility. Our experiments show that xDDR substantially outperforms minimum hop count, ETX and HETX in terms of end-to-end packet delivery ratio in static as well as mobile scenarios.

关键词： Asymmetric link quality Link-quality measurement Wireless ad hoe networks

New Hybrid EWMA Charts for Efficient Process Dispersion Monitoring with Application in Automobile Industry

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Computer Modeling in Engineering & Sciences 2022年第5期131卷 1171-1195页

作者： Xuechen Liu majid Khan Zahid Rasheed syed Masroor Anwar Muhammad Arslan Faculty of Economics Taiyuan Normal UniversityTaiyuan030619China Department of Mathematics and Statistics Riphah International UniversityIslamabad44000Pakistan Department of Mathematics Women University of Azad Jammu and KashmirBagh12500Pakistan Department of Statistics University of Azad Jammu and KashmirMuzaffarabad13100Pakistan School of Statistics Shanxi University of Finance and EconomicsTaiyuan030619China

The EWMAcharts are thewell-knownmemory-type charts used formonitoring the small-to-intermediate shifts in the process parameters(location and/or dispersion).The hybrid EWMA(HEWMA)charts are enhanced version of the EWMA charts,which effectivelymonitor the process *** paper aims to develop two new uppersided HEWMAcharts for monitoring shifts in process variance,i.e.,HEWMA1 and HEWMA2 *** design structures of the proposed HEWMA1 and HEWMA2 charts are based on the concept of integrating the features of two ***1 and HEWMA2charts plotting statistics are developed using one EWMAstatistic as input for the other *** Carlo simulations method is used as a computational technique to determine the numerical results for the performance characteristics,such as average run length(ARL),median run length,and standard deviation run length(SDRL)for assessing the performance of the proposed HEWMA1 and HEWMA2 *** addition,to evaluate the overall performance of the proposed HEWMA1 and HEWMA2 charts,other numerical measures consisting of the extra quadratic loss(EQL),relative average run length(RARL),and performance comparison index(PCI)are also *** proposed HEWMA1 and HEWMA2 charts are compared to some existing charts,such as CH,CEWMA,HEWMA,AEWMAHHW1,HHW2,AIB-EWMA-I,and AIB-EWMA-II charts,on the basis aforementioned numerical *** comparison reveals that the proposed HEWMA1 and HEWMA2 charts achieve better detection ability against the existing *** the end,a real-life data application is also provided to enhance the implementation of the proposed HEWMA1 and HEWMA2 charts practically.

关键词： Average run length extra quadratic loss memory-type charts Monte Carlo simulations smoothing parameter

二氧化硫脲:一锅合成吡喃并[4,3-b] 吡喃类化合物的高效可重复使用有机催化剂（英文）

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催化学报 2014年第1期35卷 127-133页

作者： majid Ghashang syed Sheik Mansoor Krishnamoorthy Aswin Faculty of Sciences Najafabad Branch Islamic Azad University Research Department of Chemistry Bioactive Organic Molecule Synthetic Unit C.Abdul Hakeem College

A series of pyrano[4,3‐b]pyran derivatives have been synthesized in excellent yields by the reaction of aromatic aldehydes with malononitrile or cyanoacetate and 4‐hydroxy‐6‐methylpyran‐2‐one in water at 80 °C, with the transformation being catalyzed by an aqueous solution of thiourea dioxide(TUD). Upon completion of the reaction, the product was isolated by filtration or extraction and the remaining aqueous TUD solution could be reused several times without any discernible impact on its catalytic activity. This procedure offers several advantages over existing procedures, including high yields, operational simplicity, the use of a non‐toxic catalyst and solvent, short reaction time and minimum pollution of the environment, making it a useful and attractive process for the preparation of pyrano[4,3‐b]pyran derivatives.

关键词：吡喃衍生物有机催化剂一锅法合成可重复使用二氧化硫脲水溶液反应时间催化活性

Poly(4-vinylpyridinium)hydrogen sulfate:A novel and efficient catalyst for the synthesis of 13-aryl-indeno[1,2-b]naphtha[1,2-e]pyran-12(13H)-ones under solvent-free conditions

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催化学报 2014年第1期35卷 43-48页

作者： majid Ghashang syed Sheik Mansoor Krishnamoorthy Aswin Faculty of Sciences Najafabad Branch Islamic Azad University Najafabad Esfahan Iran Bioactive Organic Molecule Synthetic Unit Research Department of Chemistry C Abdul Hakeem College Melvisharam - 632 509 Tamil Nadu India

An facile and efficient protocol for the synthesis of 13‐aryl‐indeno[1,2‐b]naphtha[1,2‐e]pyran‐ 12(13H)‐ ones has been developed that proceeds via the one‐pot three‐component sequential reaction of an aromatic aldehyde with β‐naphthol and 2H‐indene‐1,3‐dione under solvent‐free conditions in the presence of a poly(4‐vinylpyridinium)hydrogen sulfate(P(4‐VPH)HSO4) catalyst. The catalyst can be reused several times, making this procedure facile, practical, and sustainable. The simple experimental procedure, solvent‐free reaction conditions, use of an inexpensive catalyst, short react time, and excellent yields are some of the major advantages of this methodology.

关键词：乙烯基吡啶合成条件催化剂无溶剂硫酸氢萘酚二酮芳基