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Mutational analysis of hepatitis E virus ORF1 'Y-domain' : Effects on RNA replication and virion infectivity

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World Journal of Gastroenterology 2017年第4期23卷 590-602页

作者： Mohammad Khalid parvez Department of Pharmacognosy King Saud University College of PharmacyRiyadh 11451Saudi Arabia

AIMTo investigate the role of non-structural open reading frame 1 “Y-domain” sequences in the hepatitis E virus (HEV) life *** of human HEV Y-domain (amino acid sequences 216-442) and closely-related viruses were analyzed in silico. Site-directed mutagenesis of the Y-domain (HEV SAR55) was carried out and studied in the replicon-baculovirus-hepatoma cell model. In vitro transcribed mRNA (pSK-GFP) constructs were transfected into S10-3 cells and viral RNA replicating GFP-positive cells were scored by flow cytometry. Mutant virions’ infectivity was assayed on naïve HepG2/C3A *** silico analysis identified a potential palmitoylation-site (C336C337) and an α-helix segment (L410Y411S412W413L414F415E416) in the HEV Y-domain. Molecular characterization of C336A, C337A and W413A mutants of the three universally conserved residues showed non-viability. Further, of the 10 consecutive saturation mutants covering the entire Y-domain nucleotide sequences (nts 650-1339), three constructs (nts 788-994) severely affected virus replication. This revealed the indispensability of the internal sequences but not of the up- or downstream sequences at the transcriptional level. Interestingly, the three mutated residues corresponded to the downstream codons that tolerated saturation mutation, indicating their post-translational functional/structural essentiality. In addition, RNA secondary structure prediction revealed formation of stable hairpins (nts 788-994) where saturation mutation drastically inhibited virion *** is the first demonstration of the critical role of Y-domain sequences in HEV life cycle, which may involve gene regulation and/or membrane binding in intracellular replication complexes.

关键词： Hepatitis E virus Open reading frame 1 Y-domain Palmitoylation α -helix

Uses of Invasive Alien Plant Species in Rema-Kalenga Wildlife Sanctuary of Bangladesh

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Journal of Mountain Science 2010年第4期7卷 380-385页

作者： Md.parvez Rana Fahima Akhter Department of Forestry and Environmental Science Shahjalal University of Science and Technology Department of Accounting and Information System University of Chittagong

An exploratory survey was conducted on the uses and role of invasive alien species(IAS) to local livelihoods in the Rema-Kalenga Wildlife Sanctuary in the northeastern hilly region of *** was sampled in 50 quadrates,each 10 m×10 m,and 25 line transects,each 50 m×20 m,through a combination of random and systematic *** discussions were also arranged with fifty local inhabitants(17 % of the total inhabitants) to learn the various uses of IAS.A total of 17 alien plant species belonging to 10 different families,of which Leguminosae constitutes the highest number(5 species),include tree(53%) followed by herb(12%),shrub(12%) and others(weed,climber and palm).The majority of the identified species were found to be used for fuel,followed by timber production,medicinal or curative uses,fodder,and many *** addition to providing various forest products,alien tree species planted in forest plantation help provide many vital ecosystem services such as soil amelioration through nitrogen *** is true that the alien species have some negative impacts on local ecosystems,and not all of them are ***,a national programme must be initiated to distinguish the harmful from the harmless species and to identify the uses and impacts of the former and latter.

关键词： Invasive alien species Biodiversity Livelihoods Rema-Kalenga Wildlife sanctuary Bangladesh

Hot-pressed graphene nanoplatelets or/and zirconia reinforced hybrid alumina nanocomposites with improved toughness and mechanical characteristics

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Journal of Materials Science & Technology 2020年第5期40卷 135-145页

作者： Iftikhar Ahmad Mohammad Islam Nuha Al Habis Shahid parvez Center of Excellence for Research in Engineering Materials Deanship of Scientific ResearchKing Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia Mechanical Engineering Department College of EngineeringKing Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia

This work explains the synergistic contribution of graphene nanoplatelets(GNP)and zirconia ceramic nanoparticles(ZrO2)on the microstructure,mechanical performance and ballistic properties of the alumina(Al2O3)ceramic hybrid *** the benchmarked monolithic alumina,the hotpressed hybrid nanocomposite microstructure demonstrated 68%lower grain size due to grain pinning phenomenon by the homogenously distributed reinforcing GNP(0.5 wt%)and zirconia(4 wt%)***,the hybrid nanocomposite manifested 155%better fracture toughness(KIC)and 17%higher microhardness as well as 88%superior ballistic trait over the monolithic alumina,*** superior mechanical and ballistic performance of the hybrid nanocomposites was attributed to the combined role of zirconia nanoparticles and GNP nanomaterial in refining the microstructure and inducing idiosyncratic strengthening/toughening *** combined electron microscopy revealed complicated physical interlocking of the GNP into the microstructure as well as excellent bonding of the GNP with alumina at their interface in the hybrid *** also probed the efficiency of the pull-out and crack-bridging toughening mechanisms through proven quantitative *** on the information extracted from the in-depth SEM/TEM investigation,we outlined schematic models for understating the reinforcing ability as well as toughening mechanisms in the hybrid nanocomposites and meticulously *** hot-pressed hybrid nanocomposites owning high toughness and hardness may have applications in advanced armor technology.

关键词： Graphene Alumina Zirconia Toughness Hybrid nanocomposites

HBV and HIV co-infection:Impact on liver pathobiology and therapeutic approaches

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World Journal of Hepatology 2015年第1期7卷 121-126页

作者： Mohammad Khalid parvez Department of Pharmacognosy King Saud University College of PharmacyRiyadh 11451Saudi Arabia

The consequences of hepatitis B virus(HBV) and human immunodeficiency virus(HIV) co-infection on progression of severe liver diseases is a serious public health issue,worldwide. In the co-infection cases,about 90% of HIV-infected population is seropositive for HBV where approximately 5%-40% individuals are chronically infected. In HIV co-infected individuals,liverrelated mortality is estimated over 17 times higher than those with HBV mono-infection. The spectrum of HIVinduced liver diseases includes hepatitis,steatohepatitis,endothelialitis,necrosis,granulomatosis,cirrhosis andcarcinoma. Moreover,HIV co-infection significantly alters the natural history of hepatitis B,and therefore complicates the disease management. Though several studies have demonstrated impact of HIV proteins on hepatocyte biology,only a few data is available on interactions between HBV and HIV proteins. Thus,the clinical spectrum as well as the complexity of the co-infection offers challenging fronts to study the underlying molecular mechanisms,and to design effective therapeutic strategies.

关键词： Hepatitis B virus Human immunodeficiencyvirus Human immunodeficiency virus-hepatotropism Hepatitis B virus and human immunodeficiency virusco-infection Chronic hepatitis B Hepatopathogenesis

Online power quality disturbance detection by support vector machine in smart meter

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Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1328-1339页

作者： Imtiaz parvez Maryamossadat AGHILI Arif I.SARWAT Shahinur RAHMAN Fahmida ALAM Department of Electrical and Computer Engineering Florida International UniversityMiamiUSA School of Computing and Information Sciences Florida International UniversityMiamiUSA

Power quality assessment is an important performance measurement in smart *** companies are interested in power quality monitoring even in the low level distribution side such as smart *** this issue,in this study,we propose segregation of the power disturbance from regular values using one-class support vector machine(OCSVM).To precisely detect the power disturbances of a voltage wave,some practical wavelet filters are *** the unlimited types of waveform abnormalities,OCSVM is picked as a semisupervised machine learning algorithm which needs to be trained solely on a relatively large sample of normal *** model is able to automatically detect the existence of any types of disturbances in real time,even unknown types which are not available in the training *** the case of existence,the disturbances are further classified into different types such as sag,swell,transients and *** light weighted and fast,the proposed technique can be integrated into smart grid devices such as smart meter in order to perform a real-time disturbance *** continuous monitoring of power quality in smart meters will give helpful insight for quality power transmission and management.

关键词： Machine learning One-class support vector machine Power quality Disturbances Smart grid Smart meter

Inhibition of hepatitis B virus DNA replicative intermediate forms by recombinant interferon-γ

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World Journal of Gastroenterology 2006年第19期12卷 3006-3014页

作者： Mohammad Khalid parvez Deepak Sehgal Shiv Kumar Sarin Seemi Farhat Basir Shahid Jameel Department of Biosciences Jamia Millia Islamia New DelhiVirology GroupInternational Centre for Genetic Engineering and BiotechnologyNew DelhiDepartment of GastroenterologyG.B.Pant HospitalNew DelhiIndia Virology Group International Centre for Genetic Engineering and Biotechnology New DelhiIndia Department of Gastroenterology G.B.Pant Hospital New DelhiIndia Department of Biosciences Jamia Millia Islamia New DelhiIndia

AIM: To evaluate the in vitro anti-HBV activity of recombinant human IFN-γ, alone and in combination with lamivudine. METHODS: A recombinant baculovirus-HBV/HepG2 culture system was developed which could support productive HBV infection in vitro. Expression of HBsAg and HBeAg in infected HepG2 culture medium was detected by commercial enzyme immunoassays. HBV DNA replication intermediates were detected in infected cells by Southern hybridization and viral DNA load was determined by dot hybridization. RESULTS: IFN-γat 0.1 to 5μg/L efficiently down regulated HBsAg expression in transduced HepG2 cells. At 5μg/L, IFN-γalso suppressed HBV DNA replication in these cells. While treatment with a combination of lamivudine and IFN-γshowed no additive effect, sequential treatment first with lamivudine and then IFN-γwas found to be promising. In this culture system the best HBV suppression was observed with a pulse of 2μmol/L lamivudine for two days, followed by 1μg/L IFN-γfor another four days. Compared to treatment with lamivudine alone, the sequential use of 0.2μmol/L lamivudine for two days, followed by 5μg/L IFN-γfor six days showed a 72% reduction in HBV cccDNA pool. CONCLUSION: This in vitro study warrants further evaluation of a combination of IFN-γand lamivudine, especially in IFN-αnon-responder chronic hepatitis B patients. A reduced duration of lamivudine treatment would also restrict the emergence of drug-resistant HBV mutants.

关键词： Hepatitis B virus (HBV) Lamivudine Interferon-γ Replicative intermediates cccDNA

Garg incontinence scores: New scoring system on the horizon to evaluate fecal incontinence. Will it make a difference?

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World Journal of Gastroenterology 2024年第3期30卷 204-210页

作者： Petr Tsarkov Inna Tulina parvez Sheikh Darya D Shlyk Pankaj Garg Department of Colorectal Surgery Sechenov First Moscow State Medical UniversityMoscow 119991Russia Department of Oncologic Colorectal Surgery Sechenov First Moscow State Medical UniversityMoscow 119991Russia Department of Colorectal Surgery Saifee HospitalMumbai 400004MaharashtraIndia Department of Colorectal Surgery Garg Fistula Research InstitutePanchkula 134113HaryanaIndia

The main aim of this opinion review is to comment on the recent article published by Garg et al in the World Journal of Gastroenterology 2023;29:4593–*** authors in the published article developed a new scoring system,Garg incon-tinence scores(GIS),for fecal incontinence(FI).FI is a chronic debilitating disease that has a severe negative impact on the quality of life of the *** IV criteria define FI as multiple episodes of solid or liquid stool passed into the clothes at least twice a *** associated social stigmatization often leads to significant under-reporting of the condition,which further impairs *** important point is that the complexity and vagueness of the disease make it difficult for the patients to properly define and report the magnitude of the problem to their *** to this,the management becomes even more *** issue is resolved up to a considerable extent by a scoring *** were several scoring systems in use for the last three *** prominent of them were the Cleveland Clinic scoring system or the Wexner scoring system,*** Hospital or Vaizey’s scores,and the FI severity ***,there were several shortcomings in these scoring *** the opinion review,we tried to analyze the strength of GIS and compare it to the existing scoring *** main pitfalls in the existing scoring systems were that most of them gave equal weightage to different types of FI(solid,liquid,flatus,etc.),were not comprehensive,and took only the surgeon’s perception of FI into *** GIS,almost all shortcomings of previous scoring systems had been addressed:different weights were assigned to different types of FI by a robust statistical methodology;the scoring system was made comprehensive by including all types of FI that were previously omitted(urge,stress and mucus FI)and gave priority to patients’rather than the physicians’perceptions while developing the scoring *** to this,GIS in

关键词： Fecal incontinence Scoring system Urge Stress Flatus

Central pancreatectomy:a new technique for resection of selected pancreatic tumors

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Hepatobiliary & Pancreatic Diseases International 2009年第1期8卷 93-96页

作者： Omar J Shah Irfan Robbani parvez Nazir Athar B Khan Department of Surgical Gastroenterology Sheri-Kashmir Institute of Medical Sciences Department of Radiodiagnosis/Imaging Sheri-Kashmir Institute of Medical Sciences

BACKGROUND:Pancreatic tumors located in the neck region usually require pancreaticoduodenectomy or *** small benign tumors enucleation is not usually feasible due to their size and localization;then pancreatectomy is often *** pancreatectomy consists of a limited resection of the midportion of the pancreas and can be offered in benign and low-grade malignant tumors of the neck of the *** study aimed to evaluate whether central pancreatectomy has a place in pancreatic surgery. METHODS:In this study,which covered a period of 14 months,we performed central pancreatectomy in four selected *** evaluation and operative frozen section biopsy in indicated cases allowed proper selection for the *** details,complications and follow-up were recorded. RESULTS:Four patients,two with serous cystadenoma,and one with an islet cell tumor,and one with a hydatid cyst, were identified for the *** mean tumor size was 3 cm,the mean operative time was 217.5 minutes,and the mean blood loss was 382.5 *** was no morbidity or mortality in this *** endocrine or exocrine deficiency was observed in any patient during a mean follow-up of 22.7 months. CONCLUSIONS:Central pancreatectomy is a procedure that offers excellent results in benign and low-grade malignant *** preserves functional elements(endocrine and exocrine)of the pancreas and also eliminates the infective and hematological effects of ***,central pancreatectomy should be included in the armamentarium of pancreatic surgery,and in order to obtain good results,proper indications and adequate experience are recommended.

关键词： central pancreatectomy benign pancreatic tumors low-grade malignant tumor

Multiscale Modelling of Aerospace Composites——A Perspective

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民用飞机设计与研究 2017年第3期 42-48页

作者： parvez Alam Institute for Materials and Processes School of EngineeringUniversity of Edinburgh

This paper introduces a series of approaches in the modelling of composites with complex multiscale structures and *** theory underlying multiscale structures are brought to light and *** can be considerable benefit in the representative application of multiscale modelling techniques to civil aircraft design and this aim of this paper is to provide essential perspectives from several fields of research that may be beneficial to aerospace composites modelling methodologies if applied appropriately.

关键词：民用航空飞机设计理论工艺设计