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      • KCI등재

        Aberrant Promoter Methylation at CpG Cytosines Induce the Upregulation of the E2F5 Gene in Breast Cancer

        Arshad Ali,Farman Ullah,Irum Sabir Ali,Ahmad Faraz,Mumtaz Khan,Syed Tahir Ali Shah,Nawab Ali,Muhammad Saeed 한국유방암학회 2016 Journal of breast cancer Vol.19 No.2

        Purpose: The promoter methylation status of cell cycle regulatory genes plays a crucial role in the regulation of the eukaryotic cell cycle. CpG cytosines are actively subjected to methylation during tumorigenesis, resulting in gain/loss of function. E2F5 gene has growth repressive activities; various studies suggest its involvement in tumorigenesis. This study aims to investigate the epigenetic regulation of E2F5 in breast cancer to better understand tumor biology. Methods: The promoter methylation status of 50 breast tumor tissues and adjacent normal control tissues was analyzed. mRNA expression was determined using SYBR® green quantitative polymerase chain reaction (PCR), and methylation- specific PCR was performed for bisulfite-modified genomic DNA using E2F5-specific primers to assess promoter methylation. Data was statistically analyzed. Results: Significant (p<0.001) upregulation was observed in E2F5 expression among tumor tissues, relative to the control group. These samples were hypo-methylated at the E2F5 promoter region in the tumor tissues, compared to the control. Change in the methylation status (Δmeth) was significantly lower (p=0.022) in the tumor samples, indicating possible involvement in tumorigenesis. Patients at the postmenopausal stage showed higher methylation (75%) than those at the premenopausal stage (23.1%). Interestingly, methylation levels gradually increased from the early to the advanced stages of the disease (p<0.001), which suggests a putative role of E2F5 methylation in disease progression that can significantly modulate tumor biology at more advanced stage and at postmenopausal age (Pearson’s r=0.99 and 0.86, respectively). Among tissues with different histological status, methylation frequency was higher in invasive lobular carcinoma (80.0%), followed by invasive ductal carcinoma (46.7%) and ductal carcinoma in situ (20.0%). Conclusion: Methylation is an important epigenetic factor that might be involved in the upregulation of E2F5 gene in tumor tissues, which can be used as a prognostic marker for breast cancer.

      • KCI등재

        4-Hexylresorcinol sensor development based on wet-chemically prepared Co3O4@Er2O3 nanorods: A practical approach

        Tahir Ali Sheikh,Mohammed M. Rahman,Abdullah M. Asiri,Hadi M. Marwani,Md. Rabiul Awual 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.66 No.-

        In this approach, Co3O4@Er2O3 nanorods (NRs) were prepared by a wet-chemical method using reducing agents in alkaline medium. The resulting nanoparticles were characterized in details by UV/Vis and FT-IR spectroscopy, X-ray powder diffraction, Elemental dispersive analysis (EDS) coupled with field-emission scanning electron microscopy (FESEM). Co3O4@Er2O3NRs were deposited on a glassy carbon electrode (GCE) to give a selective sensor with a fast response toward 4-hexyl resorcinol (4-HR) in phosphate buffer phase (PBS) by electrochemical approach. The 4-HR sensor also displays good sensitivity, large linear dynamic range, lowest detection limit, and long-term stability, and enhanced electrochemical response. The calibration plot is linear over the 0.1 nM–0.01 M 4-HR concentration range. The sensitivity is ∼14.765 μAμM−1cm−2, and the detection limit is 64.29 pM (signal-to-noise ratio, at a SNR of 3). We also discuss possible future prospective uses of this doped metal oxide semiconductor nanomaterial in terms of chemical sensing.

      • KCI등재

        Carbon sequestrating fertilizers as a tool for carbon sequestration in agriculture under aridisols

        Tahir Mukkram Ali,Hamza Ameer,Noor-us-Sabah,Hussain Sajad,Xie Zuoming,Brestic Marian,Rastogi Anshu,Allakhverdiev Suleyman I.,Sarwar Ghulam 한국탄소학회 2022 Carbon Letters Vol.32 No.7

        Carbon is a part of all living creatures and it is the chief constructing block for life on this planet carbon occurs in several appearances, mainly as plant biomass, organic matter in soil, as gas CO2 in the air and dissipated in seawater. Soil carbon exhausts when production of carbon increases than carbon contribution. Soil comprises nearly 75% of total carbon existing on land, more than the quantity stockpiled in living animals and plants. So, soil plays a major part in maintaining a stable carbon cycle. Over the previous 150-year-period, the quantity of carbon present in the air has amplified by 30%. Majority of scientists thought that there is a straight relationship amongst amplified levels of CO2 in the air and increasing global warming. One anticipated technique to diminish atmospheric CO2 is to escalate the global packing of carbon in soils. Therefore, there is a necessity to manage soils because soil comprises more inorganic carbon as compared to the atmosphere and more organic carbon as compared to the biosphere. Soil is also thought to be a lively and important constituent in global carbon discharge and potential of sequestration. Carbon sequestration, known commonly as C-storage, can be acquired by different controlling practices, and the size of various management techniques, to enhance C-storage of soil and offer a key basin for atmospheric CO2, can be assessed most persuasively from studies conducted over long time that underwrite exclusive data on soil C accumulation, losses and storage. Sequestration happens when input of carbon enhances as compared to output of carbon. Soil carbon sequestration is the method of relocating CO2 from the air in to the soil with crop leftover and additional organic solids and in a configuration that is not instantly emitted back to the atmosphere. This review focused on beneficial role of carbon sequestrating fertilizers (press mud, boiler ash and compost) in carbon sequestration and soil properties.

      • KCI등재

        Antihematotoxic Role of Bunium persicum Seed Differential Extracts in Animal Model: Reactive Oxygen Species Might Be a Contributor

        Tahir Ali,Kamran Saeed,Muhammad Abdullah,Iram Murtaza 질병관리본부 2014 Osong Public Health and Research Persptectives Vol.5 No.6

        Objectives: Humans have been using plants as natural medicines since prehistoric times. Bunium persicum is a rich source of oils with different biological activities such as antioxidative and antimicrobial activities. The aim of this study is to evaluate the antihematotoxic and antioxidative effects of the differential extracts of B. persicum against leukemic blood induced hematotoxicity in an animal model. Methods: This study was performed on animals, which were divided into several groups: normal control, disease control, and groups that were administered with differential extracts of plants. We measured the concentration of free radical [reactive oxygen species (ROS)] and hematological parameters as blast cells from the tibia and femur in different groups. Results: The ROS level and blast cells count were higher in disease control groups than in groups treated with varying amounts of B. persicum extract and the normal group. Moreover, there was an imbalance in hematological parameters in untreated and treated groups with a correlation between free radicals and plant extract administration. Conclusion: These findings may indicate a possible link between free radicals and hematotoxicity and blast cells, while depicting a potential therapeutic role for B. persicum against ROS-induced hematotoxicity.

      • SCISCIESCOPUS

        Anthocyanin-Loaded PEG-Gold Nanoparticles Enhanced the Neuroprotection of Anthocyanins in an Aβ1–42 Mouse Model of Alzheimer’s Disease

        Ali, Tahir,Kim, Min Ju,Rehman, Shafiq Ur,Ahmad, Ashfaq,Kim, Myeong Ok Springer-Verlag 2017 Molecular Neurobiology Vol.54 No.8

        <P>Nanomedicine is an emerging research area. In this study, we investigated the neuroprotective efficacy of anthocyanin-loaded polyethylene glycol-gold nanoparticles (PEG-AuNPs) for enhancing the neuroprotective efficacy of anthocyanins in an amyloid beta (A beta)(1-42) mouse model of Alzheimer's disease. We observed that both anthocyaninloaded PEG-AuNPs and anthocyanins treatment (12 mu g/g/day for 14 days) ameliorated memory impairments in the A beta(1-42)-injected mice. However, the anthocyanin-loaded PEG-AuNPs were more effective than free anthocyanins. Anthocyanin-loaded PEG-AuNPs protected pre-and post-synaptic proteins from A beta(1-42)-induced synaptic dysfunction. Interestingly, the anthocyanin-loaded PEG-AuNPs also regulated the p-PI3K/p-Akt/p-GSK3 beta pathway and, as a result, prevented the hyperphosphorylation of tau protein at serines 413 and 404 in the A beta(1-42)-injected mice. Western blot results of cytochrome c, Bax/Bcl2, caspases and poly (ADP-ribose) polymerase-1 expression levels, and immunohistochemical Nissl and Fluoro-Jade B staining also indicated that the anthocyanin-loaded PEG-AuNPs inhibited apoptosis and neurodegeneration in the A beta(1-42)-injected mice. Our results suggest that the conjugation of dietary polyphenolic compounds with gold nanoparticles, such as anthocyanin-loaded PEG-AuNPs, is a novel approach that may represent an important and promising nanomedicine strategy to prevent age-associated neurodegenerative diseases.</P>

      • KCI등재

        Controlling the selectivity and deactivation of H-ZSM-5 by tuning b-axis channel length for glycerol dehydration to acrolein

        Babar Ali,Xiaocheng Lan,Muhammad Tahir Arslan,Syed Zulfiqar Ali Gilani,Huanjun Wang,Tiefeng Wang 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.88 No.-

        Glycerol dehydration to value-added acrolein over zeolite catalysts is a useful approach to offer asustainable economic route for the biodiesel industry. Glycerol dehydration over H-ZSM-5 withconventional morphology often exhibits a significant mass transfer limitation and inhibits the access toactive sites in the micropores, which causes low activity, selectivity, and severe catalyst deactivation. Inthis study, a significant impact of b-axis channel length on acrolein selectivity and catalyst activity wasrevealed by using H-ZSM-5 synthesized with varied channel length in b-axis of 60, 130, 180, and 250 nm. Complete glycerol conversion and high acrolein selectivity (88%) were observed over H-ZSM-5 with60 nm channels length in b-axis, due to high availability of active sites and enhanced diffusion throughthe shortest channels, which dramatically suppressed the coke formation. The catalysts with long b-axischannels exhibited a slow internal diffusion, leading to increased polymerization side reactions and cokeformation.

      • KCI등재

        Does CSR influence sustained competitive advantage and behavioral outcomes? An empirical study in the hospitality sector

        Islam Tahir,Khan Mumtaz,Ghaffar Abdul,Wang Ying,Mubarik Muhammad Shujaat,Ali Imtiaz Haider,Shahid Zubair Ali,Rehmani Mahmood,Sharma Anshuman 한국마케팅과학회 2023 마케팅과학연구 Vol.33 No.1

        This research examines the underlying mechanism through which corporate social responsibility (CSR) influences customer loyalty in the hospitality sector. A survey conducted in three popular tourist cities in China reveals that CSR positively impacts customer loyalty through institutional-level constructs, including corporate image and sustained competitive advantage, and individual-level constructs, including customer trust and customer satisfaction. Moreover, the core capabilities of organizations moderate the effect of CSR on corporate image and sustained competitive advantage. Corporate image sustained advantage, and customer satisfaction also mediates the relationship between CSR and customer loyalty. The theoretical and practical implications of these findings are discussed.

      • KCI등재

        Privacy-preserving COVID-19 Contact Tracing using Blockchain

        Shahzaib Tahir,Hasan Tahir,Ali Sajjad,Muttukrishnan Rajarajan,Fawad Khan 한국통신학회 2021 Journal of communications and networks Vol.23 No.5

        The outbreak of the COVID-19 virus has causedwidespread panic and global initiatives are geared towards treatmentand limiting its spread. With technological advancements,several mechanisms and mobile applications have been developedthat attempt to trace the physical contact made by a personwith someone who has been tested COVID-19 positive. Whiledesigning these apps, user’s privacy has been an afterthoughtand has resulted in mass violations of privacy of the public andthe patients. A total of 32 countries have designed apps andrely on them as a strategy to flatten the pandemic curve. Alongwith lack of privacy, these methodologies are centralized, wherethey are fully controlled by the government and the healthcareproviders. Owing to these and many other concerns, peopleare hesitant in the adoption of these technologies. This paperpresents a detailed analysis of user tracking apps belongingto 32 countries, thus demonstrating that they collect personaldata and are a gross violation of user privacy. This paperpresents a novel architecture for the efficient, effective andprivacy-preserving contact tracing of COVID-19 patients usingblockchain. The proposed architecture preserves the privacy ofindividuals and their contact history by encrypting all the dataspecific to an individual using a privacy-preserving Homomorphicencryption scheme and storing it on a permissioned blockchainnetwork. The contacts made with a COVID-19 positive patientare identified by performing search queries directly over theHomomorphic encrypted data stored in the blocks. Therefore,only those contacts that are suspected to be COVID-19 positivemay be decrypted by the healthcare professional or governmentfor further contact tracing/ diagnosis and COVID-19 testing;thereby leading to enhanced privacy.

      • Identification of Proteins Differentially Expressed in the Striatum by Melatonin in a Middle Cerebral Artery Occlusion Rat Model—a Proteomic and <i>in silico</i> Approach

        Shah, Fawad Ali,Zeb, Amir,Ali, Tahir,Muhammad, Tahir,Faheem, Muhammad,Alam, Sayed Ibrar,Saeed, Kamran,Koh, Phil-Ok,Lee, Keun Woo,Kim, Myeong Ok Frontiers Media S.A. 2018 Frontiers in neuroscience Vol.12 No.-

        <P>Ischemic stroke is characterized by permanent or transient obstruction of blood flow, which initiates a cascading pathological process, starting from acute ATP loss to subsequent membrane depolarization, glutamate excitotoxicity, and calcium overload. Melatonin is a potent antioxidant that exerts protective effects in different experimental stroke models. In this study, melatonin effects were demonstrated by a proteomic and <I>in silico</I> approach. The proteomic study identified differentially expressed proteins by 2D gel electrophoresis in the striatum 24 h after middle cerebral artery occlusion. Proteomic analysis revealed several proteins with aberrant expression and was validated by western blot and immunofluorescence analysis. Homology modeling was performed to build 3D structures for γ-enolase, thioredoxin (TRX), and heat shock 60 (HSP60) by the template crystal structures using a protein data bank as a sequence database. The structure refinement of each model was achieved by energy minimization via molecular dynamic simulation, and the generated models were further assessed for stability by Procheck and ProSA. The models were processed for docking analysis using AutoDock Vina, and post-docking analysis was determined by discovery studio. The proteomic study showed decreased expression of γ-enolase, TRX, and protein phosphatase 2A subunit B and increased expression of collapsin response mediator protein 2 and HSP60 in the striatum after ischemic injury. Treatment with melatonin modulated the expression profiles of these proteins. This study demonstrated the neuroprotective role of melatonin in the ischemic striatum using a proteomic and <I>in silico</I> approach. Collectively, melatonin may act in a multimechanistic way by modulating the expression of several proteins in the ischemic striatum.</P>

      • KCI등재

        Exploiting W. Ellison model for seawater communication at gigahertz frequencies based on world ocean atlas data

        Tahir, Muhammad,Ali, Iftikhar,Yan, Piao,Jafri, Mohsin Raza,Jiang, Zexin,Di, Xiaoqiang Electronics and Telecommunications Research Instit 2020 ETRI Journal Vol.42 No.4

        Electromagnetic (EM) waves used to send signals under seawater are normally restricted to low frequencies (f) because of sudden exponential increases of attenuation (𝛼) at higher f. The mathematics of EM wave propagation in seawater demonstrate dependence on relative permeability (𝜇<sub>r</sub>), relative permittivity (𝜀<sub>r</sub>), conductivity (𝜎), and f of transmission. Estimation of 𝜀<sub>r</sub> and 𝜎 based on the W. Ellison interpolation model was performed for averaged real-time data of temperature (T) and salinity (S) from 1955 to 2012 for all oceans with 41 088 latitude/longitude points and 101 depth points up to 5500 m. Estimation of parameters such as real and imaginary parts of 𝜀<sub>r</sub>, 𝜀<sub>r</sub>', 𝜀<sub>r</sub>", 𝜎, loss tangent (tan 𝛿), propagation velocity (V<sub>p</sub>), phase constant (𝛽), and α contributes to absorption loss (L<sub>a</sub>) for seawater channels carried out by using normal distribution fit in the 3 GHz-40 GHz f range. We also estimated total path loss (L<sub>PL</sub>) in seawater for given transmission power P<sub>t</sub> and antenna (dipole) gain. MATLAB is the simulation tool used for analysis.

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