Publications by authors named "Anuj Kumar"

228 Publications

Efficacy of Bacterial Nanocellulose in Hard Tissue Regeneration: A Review.

Materials (Basel) 2021 Aug 24;14(17). Epub 2021 Aug 24.

School of Chemical Engineering, Yeungnam University, 280 Daehak-ro, Gyeongsan 38541, Korea.

Bacterial nanocellulose (BNC, as exopolysaccharide) synthesized by some specific bacteria strains is a fascinating biopolymer composed of the three-dimensional pure cellulosic nanofibrous matrix without containing lignin, hemicellulose, pectin, and other impurities as in plant-based cellulose. Due to its excellent biocompatibility (in vitro and in vivo), high water-holding capacity, flexibility, high mechanical properties, and a large number of hydroxyl groups that are most similar characteristics of native tissues, BNC has shown great potential in tissue engineering applications. This review focuses on and discusses the efficacy of BNC- or BNC-based biomaterials for hard tissue regeneration. In this review, we provide brief information on the key aspects of synthesis and properties of BNC, including solubility, biodegradability, thermal stability, antimicrobial ability, toxicity, and cellular response. Further, modification approaches are discussed briefly to improve the properties of BNC or BNC-based structures. In addition, various biomaterials by using BNC (as sacrificial template or matrix) or BNC in conjugation with polymers and/or fillers are reviewed and discussed for dental and bone tissue engineering applications. Moreover, the conclusion with perspective for future research directions of using BNC for hard tissue regeneration is briefly discussed.
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http://dx.doi.org/10.3390/ma14174777DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8432490PMC
August 2021

Enhanced mechanical, biomineralization, and cellular response of nanocomposite hydrogels by bioactive glass and halloysite nanotubes for bone tissue regeneration.

Mater Sci Eng C Mater Biol Appl 2021 Sep 18;128:112236. Epub 2021 Jun 18.

School of Chemical Engineering, Yeungnam University, 280 Daehak-ro, Gyeongsan 38541, South Korea; Research Institute of Cell Culture, Yeungnam University, 280 Daehak-ro, Gyeongsan 38541, South Korea. Electronic address:

In the present study, the synergistic effect of the bioactive glass (BG) and halloysite nanotubes (HNTs) (i.e. [email protected]) was evaluated on physicochemical and bioactive properties of polyacrylamide/poly (vinyl alcohol) (PMPV) based nanocomposite hydrogels. Here, a double-network hydrogel composed of organic-inorganic components was successfully developed by using in-situ free-radical polymerization and freeze-thawing process. Structural analyses confirmed the successful formation of the nanocomposite hydrogels through physical and chemical interactions. Morphological analysis showed that all hydrogel scaffolds are containing highly porous 3D microstructure and pore-interconnectivity. The equilibrium swelling ratio of the hydrogels was decreased by the addition of BG or [email protected] and thereby the lower porosity and pore-size reduced the penetration of media and slow down the degradation process. Enhanced biomineralization ability of PMPV/[email protected] was observed via apatite-forming ability (Ca/P: 1.21 ± 0.14) after immersion in the simulated body fluid as well as significantly enhanced dynamic mechanical properties (compressive strength: 102.1 kPa at 45% of strain and stiffness: 3115.0 N/m at 15% of strain). Furthermore, an enhanced attachment and growth of hFOB1.19 osteoblast cells on PMPV/[email protected] was achieved compared to PMPV or PMPV/BG hydrogels over 14 days. The PMPV/[email protected] nanocomposite hydrogel could have a promising application in low-load bearing bone tissue regeneration.
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http://dx.doi.org/10.1016/j.msec.2021.112236DOI Listing
September 2021

Estimation of Number of Graphene Layers Using Different Methods: A Focused Review.

Materials (Basel) 2021 Aug 16;14(16). Epub 2021 Aug 16.

School of Mechanical Engineering, Yeungnam University, Gyeongsan 38541, Korea.

Graphene, a two-dimensional nanosheet, is composed of carbon species (sp hybridized carbon atoms) and is the center of attention for researchers due to its extraordinary physicochemical (e.g., optical transparency, electrical, thermal conductivity, and mechanical) properties. Graphene can be synthesized using top-down or bottom-up approaches and is used in the electronics and medical (e.g., drug delivery, tissue engineering, biosensors) fields as well as in photovoltaic systems. However, the mass production of graphene and the means of transferring monolayer graphene for commercial purposes are still under investigation. When graphene layers are stacked as flakes, they have substantial impacts on the properties of graphene-based materials, and the layering of graphene obtained using different approaches varies. The determination of number of graphene layers is very important since the properties exhibited by monolayer graphene decrease as the number of graphene layer per flake increases to 5 as few-layer graphene, 10 as multilayer graphene, and more than 10 layers, when it behaves like bulk graphite. Thus, this review summarizes graphene developments and production. In addition, the efficacies of determining the number of graphene layers using various characterization methods (e.g., transmission electron microscopy (TEM), atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectra and mapping, and spin hall effect-based methods) are compared. Among these methods, TEM and Raman spectra were found to be most promising to determine number of graphene layers and their stacking order.
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http://dx.doi.org/10.3390/ma14164590DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8399741PMC
August 2021

Discovery of miRNAs and Development of Heat-Responsive miRNA-SSR Markers for Characterization of Wheat Germplasm for Terminal Heat Tolerance Breeding.

Front Genet 2021 28;12:699420. Epub 2021 Jul 28.

Department of Molecular Biology, Biotechnology and Bioinformatics, College of Basic Sciences and Humanities, CCS Haryana Agricultural University, Hisar, India.

A large proportion of the Asian population fulfills their energy requirements from wheat ( L.). Wheat quality and yield are critically affected by the terminal heat stress across the globe. It affects approximately 40% of the wheat-cultivating regions of the world. Therefore, there is a critical need to develop improved terminal heat-tolerant wheat varieties. Marker-assisted breeding with genic simple sequence repeats (SSR) markers have been used for developing terminal heat-tolerant wheat varieties; however, only few studies involved the use of microRNA (miRNA)-based SSR markers (miRNA-SSRs) in wheat, which were found as key players in various abiotic stresses. In the present study, we identified 104 heat-stress-responsive miRNAs reported in various crops. Out of these, 70 miRNA-SSR markers have been validated on a set of 20 terminal heat-tolerant and heat-susceptible wheat genotypes. Among these, only 19 miRNA-SSR markers were found to be polymorphic, which were further used to study the genetic diversity and population structure. The polymorphic miRNA-SSRs amplified 61 SSR loci with an average of 2.9 alleles per locus. The polymorphic information content (PIC) value of polymorphic miRNA-SSRs ranged from 0.10 to 0.87 with a mean value of 0.48. The dendrogram constructed using unweighted neighbor-joining method and population structure analysis clustered these 20 wheat genotypes into 3 clusters. The target genes of these miRNAs are involved either directly or indirectly in providing tolerance to heat stress. Furthermore, two polymorphic markers miR159c and miR165b were declared as very promising diagnostic markers, since these markers showed specific alleles and discriminated terminal heat-tolerant genotypes from the susceptible genotypes. Thus, these identified miRNA-SSR markers will prove useful in the characterization of wheat germplasm through the study of genetic diversity and population structural analysis and in wheat molecular breeding programs aimed at terminal heat tolerance of wheat varieties.
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http://dx.doi.org/10.3389/fgene.2021.699420DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8356722PMC
July 2021

The Complex Genetic Basis and Multilayered Regulatory Control of Yeast Pseudohyphal Growth.

Authors:
Anuj Kumar

Annu Rev Genet 2021 Jul 19. Epub 2021 Jul 19.

Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109, USA; email:

Eukaryotic cells are exquisitely responsive to external and internal cues, achieving precise control of seemingly diverse growth processes through a complex interplay of regulatory mechanisms. The budding yeast provides a fascinating model of cell growth in its stress-responsive transition from planktonic single cells to a filamentous pseudohyphal growth form. During pseudohyphal growth, yeast cells undergo changes in morphology, polarity, and adhesion to form extended and invasive multicellular filaments. This pseudohyphal transition has been studied extensively as a model of conserved signaling pathways regulating cell growth and for its relevance in understanding the pathogenicity of the related opportunistic fungus , wherein filamentous growth is required for virulence. This review highlights the broad gene set enabling yeast pseudohyphal growth, signaling pathways that regulate this process, the role and regulation of proteins conferring cell adhesion, and interesting regulatory mechanisms enabling the pseudohyphal transition. Expected final online publication date for the , Volume 55 is November 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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http://dx.doi.org/10.1146/annurev-genet-071719-020249DOI Listing
July 2021

Silver-Catalyzed Direct Synthesis of Trifluoromethylated Enaminopyridines and Isoquinolinones Employing Trifluorodiazoethane.

Org Lett 2021 Aug 15;23(15):5815-5820. Epub 2021 Jul 15.

Academy of Scientific and Innovative Research, Ghaziabad 201002, India.

This Letter reports a Ag-catalyzed three-component approach for the N-alkenylation of 2-aminopyridines employing aldehydes and trifluorodiazoethane. Unlike the known reactions of trifluorodiazoethane with imines, which generate Mannich adducts, aziridines, or triazolines depending on the substrates and conditions, this reaction, after Mannich addition, proceeds via a carbene formation and 1,2-aryl migration sequence to afford ()-enaminopyridines. This surprising selectivity, which is effective for a wide range of aldehydes and 2-aminopyridines, has been subsequently explored to access trifluoromethylated isoquinolinones.
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http://dx.doi.org/10.1021/acs.orglett.1c01969DOI Listing
August 2021

Nonlinear dynamical behavior of an SEIR mathematical model: Effect of information and saturated treatment.

Chaos 2021 Apr;31(4):043104

Thapar Institute of Engineering and Technology, Patiala 147004, India.

When a disease spreads in a population, individuals tend to change their behavior due to the presence of information about disease prevalence. Therefore, the infection rate is affected and incidence term in the model should be appropriately modified. In addition, a limitation of medical resources has its impact on the dynamics of the disease. In this work, we propose and analyze an Susceptible-Exposed-Infected-Recovered (SEIR) model, which accounts for the information-induced non-monotonic incidence function and saturated treatment function. The model analysis is carried out, and it is found that when R is below one, the disease may or may not die out due to the saturated treatment (i.e., a backward bifurcation may exist and cause multi-stability). Further, we note that in this case, disease eradication is possible if medical resources are available for all. When R exceeds one, there is a possibility of the existence of multiple endemic equilibria. These multiple equilibria give rise to rich and complex dynamics by showing various bifurcations and oscillations (via Hopf bifurcation). A global asymptotic stability of a unique endemic equilibrium (when it exists) is established under certain conditions. An impact of information is shown and also a sensitivity analysis of model parameters is performed. Various cases are considered numerically to provide the insight of model behavior mathematically and epidemiologically. We found that the model shows hysteresis. Our study underlines that a limitation of medical resources may cause bi(multi)-stability in the model system. Also, information plays a significant role and gives rise to a rich and complex dynamical behavior of the model.
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http://dx.doi.org/10.1063/5.0039048DOI Listing
April 2021

Functional Exploration of Chaperonin (HSP60/10) Family Genes and their Abiotic Stress-induced Expression Patterns in .

Curr Genomics 2021 Feb;22(2):137-152

Department of Biotechnology, Vignan's Foundation for Science, Technology and Research, Vadlamudi, Guntur 522 213, Andhra Pradesh, India.

Background: , the C4 dry-land cereal, important for food, fodder, feed and fuel, is a model crop for abiotic stress tolerance with smaller genome size, genetic diversity, and bio-energy traits. The heat shock proteins/chaperonin 60s (HSP60/Cpn60s) assist the plastid proteins, and participate in the folding and aggregation of proteins. However, the functions of HSP60s in abiotic stress tolerance in remain unclear.

Methods: Genome-wide screening and characterization of SbHSP60s were carried out along with tissue and stress-specific expression analysis.

Results: A total of 36 genes were identified in . They were subdivided into 2 groups, the and co-chaperonins encoded by 30 and 6 genes, respectively. The genes are distributed on all the chromosomes, chromosome 1 being the hot spot with 9 genes. All the HSP60s were found hydrophilic and highly unstable. The genes showed a large number of introns, the majority of them with more than 10. Among the 12 paralogs, only 1 was tandem and the remaining 11 segmental, indicating their role in the expansion of . Majority of the genes expressed uniformly in leaf while a moderate expression was observed in the root tissues, with the highest expression displayed by . From expression analysis, for drought, for salt, and for heat and and have been found implicated for cold stress tolerance and appeared as the key regulatory genes.

Conclusion: This work paves the way for the utilization of chaperonin family genes for achieving abiotic stress tolerance in plants.
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http://dx.doi.org/10.2174/1389202922666210324154336DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8188580PMC
February 2021

Molecular Perspective of Nanoparticle Mediated Therapeutic Targeting in Breast Cancer: An Odyssey of Endoplasmic Reticulum Unfolded Protein Response (UPR) and Beyond.

Biomedicines 2021 Jun 2;9(6). Epub 2021 Jun 2.

School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri 185234, India.

Breast cancer (BC) is the second most frequent cause of death among women. Representing a complex and heterogeneous type of cancer, its occurrence is attributed by both genetic (gene mutations, e.g., BRCA1, BRCA2) and non-genetic (race, ethnicity, etc.) risk factors. The effectiveness of available treatment regimens (small molecules, cytotoxic agents, and inhibitors) decreased due to their poor penetration across biological barriers, limited targeting, and rapid body clearance along with their effect on normal resident cells of bone marrow, gastrointestinal tract, and hair follicles. This significantly reduced their clinical outcomes, which led to an unprecedented increase in the number of cases worldwide. Nanomedicine, a nano-formulation of therapeutics, emerged as a versatile delivering module for employment in achieving the effective and target specific delivery of pharmaceutical payloads. Adoption of nanotechnological approaches in delivering therapeutic molecules to target cells ensures not only reduced immune response and toxicity, but increases the stability of therapeutic entities in the systemic circulation that averts their degradation and as such increased extravasations and accumulation via enhanced permeation and the retention (EPR) effect in target tissues. Additionally, nanoparticle (NP)-induced ER stress, which enhances apoptosis and autophagy, has been utilized as a combative strategy in the treatment of cancerous cells. As nanoparticles-based avenues have been capitalized to achieve better efficacy of the new genera of therapeutics with enhanced specificity and safety, the present study is aimed at providing the fundamentals of BC, nanotechnological modules (organic, inorganic, and hybrid) employed in delivering different therapeutic molecules, and mechanistic insights of nano-ER stress induced apoptosis and autophagy with a perspective of exploring this avenue for use in the nano-toxicological studies. Furthermore, the current scenario of USA FDA approved nano-formulations and the future perspective of nanotechnological based interventions to overcome the existing challenges are also discussed.
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http://dx.doi.org/10.3390/biomedicines9060635DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8229605PMC
June 2021

Functional Heterogeneity of Mammalian IFITM Proteins against HIV-1.

J Virol 2021 Aug 25;95(18):e0043921. Epub 2021 Aug 25.

Centre International de Recherche en Infectiologie (CIRI), University of Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, Lyon, France.

Interferon-induced transmembrane proteins (IFITMs) are a family of interferon-inducible proteins that inhibit a broad range of viruses by interfering with viral-to-cellular membrane fusion. The antiviral activity of IFITMs is highly regulated by several posttranslational modifications and by a number of protein domains that modulate steady-state protein levels, trafficking, and antiviral effectiveness. Taking advantage of the natural diversity existing among IFITMs of different animal species, we have compared 21 IFITMs for their ability to inhibit HIV-1 at two steps, during virus entry into cells (target cell protection) and during the production of novel virion particles (negative imprinting of virion particles' infectivity). We found a high functional heterogeneity among IFITM homologs with respect to both antiviral modalities, with IFITM members that exhibit enhanced viral inhibition, while others have no ability to block HIV-1. These differences could not be ascribed to known regulatory domains and could only be partially explained through differential protein stability, implying the existence of additional mechanisms. Through the use of chimeras between active and inactive IFITMs, we demonstrate that the cross talk between distinct domains of IFITMs is an important contributor of their antiviral potency. Finally, we identified murine IFITMs as natural variants competent for target cell protection, but not for negative imprinting of virion particles' infectivity, suggesting that the two properties may, at least in principle, be uncoupled. Overall, our results shed new light on the complex relationship between IFITMs and viral infection and point to the cross talk between IFITM domains as a novel layer of regulation of their activity. IFITMs are broad viral inhibitors capable of interfering with both early and late phases of the replicative cycle of many different viruses. By comparing 21 IFITM proteins issued from different animal species for their ability to inhibit HIV-1, we have identified several that exhibit either enhanced or impaired antiviral behavior. This functional diversity is not driven by differences in known domains and can only be partly explained through differential protein stability. Chimeras between active and inactive IFITMs point to the cross talk between individual IFITM domains as important for optimal antiviral activity. Finally, we show that murine IFITMs are not capable of decreasing the infectivity of newly produced HIV-1 virion particles, although they retain target cell protection abilities, suggesting that these properties may be, in principle, disconnected. Overall, our results shed new light on the complex layers of regulation of IFITM proteins and enrich our current understanding of these broad antiviral factors.
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http://dx.doi.org/10.1128/JVI.00439-21DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8387037PMC
August 2021

Molecular docking and dynamics studies of curcumin with COVID-19 proteins.

Netw Model Anal Health Inform Bioinform 2021 10;10(1):44. Epub 2021 Jun 10.

Department of Biotechnology, Vignan's Foundation for Science, Technology and Research (Deemed To Be University), Vadlamudi, Guntur, 522 213 Andhra Pradesh India.

Coronavirus disease 2019 (COVID-19) is caused by a Severe Acute Respiratory Syndrome-Coronavirus 2 (SARS-CoV-2), which is a positive-strand RNA virus. The SARS-CoV-2 genome and its association to SAR-CoV-1 vary from ca. 66 to 96% depending on the type of betacoronavirideae family members. With several drugs, viz. chloroquine, hydroxychloroquine, ivermectin, artemisinin, remdesivir, azithromycin considered for clinical trials, there has been an inherent need to find distinctive antiviral mechanisms of these drugs. Curcumin, a natural bioactive molecule has been shown to have therapeutic potential for various diseases, and its effect on COVID-19 is also currently being explored. In this study, we show the binding potential of curcumin targeted to a variety of SARS-CoV-2 proteins, viz spike glycoproteins (PDB ID: 6VYB), nucleocapsid phosphoprotein (PDB ID: 6VYO), spike protein-ACE2 (PDB ID: 6M17) along with nsp10 (PDB ID: 6W4H) and RNA dependent RNA polymerase (PDB ID: 6M71) structures. Furthermore, representative docking complexes were validated using molecular dynamics simulations and mechanistic studies at 100 ns was carried on nucleocapsid and nsp10 proteins with curcumin complexes which resulted in stable and efficient binding energies and correlated with that of docked binding energies of the complexes. Both the docking and simulation studies indicate that curcumin has the potential as an antiviral against COVID-19.
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http://dx.doi.org/10.1007/s13721-021-00312-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8192041PMC
June 2021

WheatQTLdb: a QTL database for wheat.

Mol Genet Genomics 2021 Sep 11;296(5):1051-1056. Epub 2021 Jun 11.

Department of Genetics and Plant Breeding, Chaudhary Charan Singh University, Meerut, Uttar Pradesh, 250004, India.

During the last three decades, QTL analysis in wheat has been conducted for a variety of individual traits, so that thousands of QTL along with the linked markers, their genetic positions and contribution to phenotypic variation (PV) for concerned traits are now known. However, no exhaustive database for wheat QTL is currently available at a single platform. Therefore, the present database was prepared which is an exhaustive information resource for wheat QTL data from the published literature till May, 2020. QTL data from both interval mapping and genome-wide association studies (GWAS) have been included for the following classes of traits: (i) morphological traits, (ii) N and P use efficiency, (iii) traits for biofortification (Fe, K, Se, and Zn contents), (iv) tolerance to abiotic stresses including drought, water logging, heat stress, pre-harvest sprouting and salinity, (v) resistance to biotic stresses including those due to bacterial, fungal, nematode and insects, (vi) quality traits, and (vii) a variety of physiological traits, (viii) developmental traits, and (ix) yield and its related traits. For the preparation of the database, literature was searched for data on QTL/marker-trait associations (MTAs), curated and then assembled in the form of WheatQTLdb. The available information on metaQTL, epistatic QTL and candidate genes, wherever available, is also included in the database. Information on QTL in this WheatQTLdb includes QTL names, traits, associated markers, parental genotypes, crosses/mapping populations, association mapping panels and other useful information. To our knowledge, WheatQTLdb prepared by us is the largest collection of QTL (11,552), epistatic QTL (107) and metaQTL (330) data for hexaploid wheat to be used by geneticists and plant breeders for further studies involving fine mapping, cloning, and marker-assisted selection (MAS) during wheat breeding.
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http://dx.doi.org/10.1007/s00438-021-01796-9DOI Listing
September 2021

Properties of Silicone Rubber-Based Composites Reinforced with Few-Layer Graphene and Iron Oxide or Titanium Dioxide.

Polymers (Basel) 2021 May 12;13(10). Epub 2021 May 12.

School of Mechanical Engineering, Yeungnam University, 280 Daehak-ro, Gyeongsan 38541, Korea.

The increasing demand for polymer composites with novel or improved properties requires novel fillers. To meet the challenges posed, nanofillers such as graphene, carbon nanotubes, and titanium dioxide (TiO) have been used. In the present work, few-layer graphene (FLG) and iron oxide (FeO) or TiO were used as fillers in a room-temperature-vulcanized (RTV) silicone rubber (SR) matrix. Composites were prepared by mixing RTV-SR with nanofillers and then kept for vulcanization at room temperature for 24 h. The RTV-SR composites obtained were characterized with respect to their mechanical, actuation, and magnetic properties. Fourier-transform infrared spectroscopy (FTIR) analysis was performed to investigate the composite raw materials and finished composites, and X-ray photoelectron spectroscopy (XPS) analysis was used to study composite surface elemental compositions. Results showed that mechanical properties were improved by adding fillers, and actuation displacements were dependent on the type of nanofiller used and the applied voltage. Magnetic stress-relaxation also increased with filler amount and stress-relaxation rates decreased when a magnetic field was applied parallel to the deformation axes. Thus, this study showed that the inclusion of iron oxide (FeO) or TiO fillers in RTV-SR improves mechanical, actuation, and magnetic properties.
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http://dx.doi.org/10.3390/polym13101550DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8151798PMC
May 2021

Rifampicin and Letermovir as potential repurposed drug candidate for COVID-19 treatment: insights from an in-silico study.

Pharmacol Rep 2021 Jun 10;73(3):926-938. Epub 2021 May 10.

School of Biotechnology, Gautam Buddha University, Greater Noida, Uttar Pradesh, 201310, India.

Introduction: Drug repurposing is the need of the hour considering the medical emergency caused by the COVID-19 pandemic. Recently, cytokine storm by the host immune system has been linked with high viral load, loss of lung function, acute respiratory distress syndrome (ARDS), multiple organ failure, and subsequent fatal outcome.

Objective: This study aimed to identify potential FDA approved drugs that can be repurposed for COVID-19 treatment using an in-silico analysis.

Methods: In this study, virtual screening of selected FDA approved drugs was performed by targeting the main protease (M) of SARS-CoV-2 and the key molecules involved in the 'Cytokine storm' in COVID-19 patients. Based on our preliminary screening supported by extensive literature search, we selected FDA approved drugs to target the SARS-CoV-2 main protease (M) and the key players of cytokine storm, TNF-α, IL-6, and IL-1β. These compounds were examined based on systematic docking studies and further validated using a combination of molecular dynamics simulations and molecular mechanic/generalized/Born/Poisson-Boltzmann surface area (MM/G/P/BSA) free energy calculations.

Results: Based on the findings, Rifampicin and Letermovir appeared as the most promising drug showing a very good binding affinity with the main protease of SARS-CoV-2 and TNF-α, IL-6, and IL-1β. However, it is pertinent to mention here that our findings need further validation by in vitro analysis and clinical trials.

Conclusion: This study provides an insight into the drug repurposing approach in which several FDA approved drugs were examined to inhibit COVID-19 infection by targeting the main protease of SARS-COV-2 and the cytokine storm.
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http://dx.doi.org/10.1007/s43440-021-00228-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8107206PMC
June 2021

Indoor air quality improvement in COVID-19 pandemic: Review.

Sustain Cities Soc 2021 Jul 15;70:102942. Epub 2021 Apr 15.

CSIR-Central Building Research Institute (CBRI), Roorkee, 247667, India.

Introduction: The advent of COVID-19 has impinged millions of people. The increased concern of the virus spread in confined spaces due to meteorological factors has sequentially fostered the need to improve indoor air quality.

Objective: This paper aims to review control measures and preventive sustainable solutions for the future that can deliberately help in bringing down the impact of declined air quality and prevent future biological attacks from affecting the occupant's health.

Methodology: Anontology chart is constructed based on the set objectives and review of all the possible measures to improve the indoor air quality taking into account the affecting parameters has been done.

Observations: An integrated approach considering non-pharmaceutical and engineering control measures together for a healthy indoor environment should be contemplated rather than discretizing the available solutions. Maintaining social distance by reducing occupant density and implementing a modified ventilation system with advance filters for decontamination of viral load can help in sustaining healthy indoor air quality.

Conclusion: The review paper in the main, provides a brief overview of all the improvement techniques bearing in mind thermal comfort and safety of occupants and looks for a common ground for all the technologies based on literature survey and offers recommendation for a sustainable future.
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http://dx.doi.org/10.1016/j.scs.2021.102942DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8049211PMC
July 2021

Smokeless Tobacco Initiation, Use, and Cessation in South Asia: A Qualitative Assessment.

Nicotine Tob Res 2021 Aug;23(10):1801-1804

Valid Research Ltd, Sandown House, West Yorkshire, UK.

Introduction: Smokeless tobacco (ST) is a significant South Asian public health problem. This paper reports a qualitative study of a sample of South Asian ST users.

Methods: Interviews, using a piloted topic guide, with 33 consenting, urban dwelling adult ST users explored their ST initiation, continued use, and cessation attempts. Framework data analysis was used to analyze country specific data before a thematic cross-country synthesis was completed.

Results: Participants reported long-term ST use and high dependency. All reported strong cessation motivation and multiple failed attempts because of ease of purchasing ST, tobacco dependency, and lack of institutional support.

Conclusions: Interventions to support cessation attempts among consumers of South Asian ST products should address the multiple challenges of developing an integrated ST policy, including cessation services.

Implications: This study provides detailed understanding of the barriers and drivers to ST initiation, use, and cessation for users in Bangladesh, India, and Pakistan. It is the first study to directly compare these three countries. The insight was then used to adapt an existing behavioral support intervention for ST cessation for testing in these countries.
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http://dx.doi.org/10.1093/ntr/ntab065DOI Listing
August 2021

Multinational Study to Assess Stress Levels Among the Health Care Workers of Radiation Oncology Community at the Outset of the COVID-19 Pandemic.

JCO Glob Oncol 2021 04;7:464-473

Department of Radiation Oncology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, India.

Purpose: To evaluate stress levels among the health care workers (HCWs) of the radiation oncology community in Asian countries.

Methods: HCWs of the radiation oncology departments from 29 tertiary cancer care centers of Bangladesh, India, Indonesia and Nepal were studied from May 2020 to July 2020. A total of 758 eligible HCWs were identified. The 7-Item Generalized Anxiety Disorder, 9-Item Patient Health Questionnaire, and 22-Item Impact of Events Scale-Revised were used for assessing anxiety, depression, and post-traumatic stress disorder. Univariate and multivariate analysis was done to identify the causative factors affecting mental health.

Results: A total of 758 participants from 794 HCWs were analyzed. The median age was 31 years (IQR, 27-28). The incidence of moderate to severe levels of anxiety, depression, and stress was 34.8%, 31.2%, and 18.2%, respectively. Severe personal concerns were noticed by 60.9% of the staff. On multivariate analysis, the presence of commonly reported symptoms of COVID-19 during the previous 2 weeks, contact history (harzard ratio [HR], 2.04; CI, 1.15 to 3.63), and compliance with precautionary measures (HR, 1.69; CI, 1.19 to 2.45) for COVID-19 significantly predicted for increasing anxiety (HR, 2.67; CI, 1.93 to 3.70), depression (HR, 3.38; CI 2.36 to 4.84), and stress (HR, 2.89; CI, 1.88 to 4.43) ( < .001). A significant regional variation was also noticed for anxiety, stress, and personal concerns.

Conclusion: This survey conducted during the COVID-19 pandemic revealed that a significant proportion of HCWs in the radiation oncology community experiences moderate to severe levels of anxiety, depression, and stress. This trend is alarming and it is important to identify and intervene at the right time to improve the mental health of HCWs to avoid any long-term impacts.
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http://dx.doi.org/10.1200/GO.20.00647DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8081510PMC
April 2021

Unraveling the potential role of bioactive molecules produced by spp. as inhibitors of tomatinase enzyme having an important role in wilting disease: an approach.

J Biomol Struct Dyn 2021 Mar 15:1-10. Epub 2021 Mar 15.

Centre for Rural Development & Technology, Indian Institute of Technology Delhi, New Delhi, India.

Tomatinase; a saponin detoxification enzyme produced by f.sp is reported as a causative agent for wilting disease in tomato crops. The disease is instigated by inhibiting the activity of α-tomatine. spp. widely used as biocontrol agent play an essential role in plant growth and pathogen control. In the current study, an approach using substrate docking, molecular dynamics and MM/PBSA analysis was used to evaluate the potential role of bioactive metabolites produced by spp. The study aims to establish the efficacy of catalytic tendency of the bioactive metabolites to combat the effect of tomatinase enzyme employing α-tomatine as the substrate. By means of the integrated molecular modeling approach; novel bioactive metabolites namely, Trichodermamide B, Trichosetin and Virone were found to be the potential inhibitors against tomatinase enzyme secreted by . Molecular dynamic (MD) simulations displayed that the screened ligands bound tomatinase during 150 ns of MD simulations. Furthermore, the (MM-PBSA) free energy calculations depicted that screened molecules possess stable and favorable energies for Trichodermamide B (-7.1 kcal/mol), Trichosetin (-7.4 kcal/mol) and Virone (-7.9 kcal/mol) thereby instigating robust binding with the enzyme's binding site. The results attained in this study, reflects that these bioactive metabolites may serve as potential substrates to control and inhibit the tomatinase enzyme; playing an integral role in combating the wilt disease.Communicated by Ramaswamy H. Sarma.
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http://dx.doi.org/10.1080/07391102.2021.1898476DOI Listing
March 2021

Potential of Pueraria tuberosa (Willd.) DC. to rescue cognitive decline associated with BACE1 protein of Alzheimer's disease on Drosophila model: An integrated molecular modeling and in vivo approach.

Int J Biol Macromol 2021 May 9;179:586-600. Epub 2021 Mar 9.

Phytochemistry Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Facultad de Medicina, Universidad del Azuay, Cuenca, Ecuador. Electronic address:

The indispensable role of Beta-site amyloid precursor protein cleaving enzyme-1 (BACE1) in Amyloid beta (Aβ) plaques generation and Aβ-mediated synaptic dysfunctions makes it a crucial target for therapeutic intervention in Alzheimer's disease (AD). In order to find out the potential inhibitors of BACE1, the present study focused on five phytochemicals from Pueraria tuberosa, namely, daidzin, genistin, mangiferin, puerarin, and tuberosin. A molecular docking study showed that all five phytochemicals presented the strongest BACE1 inhibition. Integrated molecular dynamics simulations and free energy calculations demonstrated that all five natural compounds have stable and favorable energies causing strong binding with the pocket site of BACE1 on 50 ns. All these molecules also passed Lipinski's rule of five. To validate the molecular modeling based findings, we primarily targeted the cognitive decline associated with BACE1 expression in AD flies with P. tuberosa. Significant improvement in cognitive decline was observed in AD flies in different behavioral assays such as Larval crawling assay (16.38%), Larval light preference assay (26.39%), Climbing assay (32.97%), Cold sensitivity assay (43.6%), and Thermal sensitivity assay (44.42%). The present findings suggest that P. tuberosa may be considered as a promising dietary supplement that can significantly ameliorate cognitive decline caused by BACE1 in Alzheimer's disease (AD).
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http://dx.doi.org/10.1016/j.ijbiomac.2021.03.032DOI Listing
May 2021

Development and use of miRNA-derived SSR markers for the study of genetic diversity, population structure, and characterization of genotypes for breeding heat tolerant wheat varieties.

PLoS One 2021 4;16(2):e0231063. Epub 2021 Feb 4.

Division of Genetics and Plant Breeding, Faculty of Agriculture (FoA), SKUAST-Kashmir, Wadura, Sopore, Kashmir, India.

Heat stress is an important abiotic factor that limits wheat production globally, including south-east Asia. The importance of micro (mi) RNAs in gene expression under various biotic and abiotic stresses is well documented. Molecular markers, specifically simple sequence repeats (SSRs), play an important role in the wheat improvement breeding programs. Given the role of miRNAs in heat stress-induced transcriptional regulation and acclimatization, the development of miRNA-derived SSRs would prove useful in studying the allelic diversity at the heat-responsive miRNA-genes in wheat. In the present study, efforts have been made to identify SSRs from 96 wheat heat-responsive miRNA-genes and their characterization using a panel of wheat genotypes with contrasting reactions (tolerance/susceptible) to heat stress. A set of 13 miRNA-derived SSR markers were successfully developed as an outcome. These miRNA-SSRs are located on 11 different common wheat chromosomes (2A, 3A, 3B, 3D, 4D, 5A, 5B, 5D, 6A, 6D, and 7A). Among 13 miRNA-SSRs, seven were polymorphic on a set of 37 selected wheat genotypes. Within these polymorphic SSRs, three makers, namely HT-169j, HT-160a, and HT-160b, were found promising as they could discriminate heat-tolerant and heat-susceptible genotypes. This is the first report of miRNA-SSR development in wheat and their deployment in genetic diversity and population structure studies and characterization of trait-specific germplasm. The study suggests that this new class of molecular makers has great potential in the marker-assisted breeding (MAB) programs targeted at improving heat tolerance and other adaptability or developmental traits in wheat and other crops.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0231063PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7861453PMC
June 2021

Crosstalk of long non-coding RNAs and EMT: Searching the missing pieces of an incomplete puzzle for lung cancer therapy.

Curr Cancer Drug Targets 2021 Feb 2. Epub 2021 Feb 2.

Sabanci University Nanotechnology Research and Application Center (SUNUM), Tuzla, 34956, Istanbul. Turkey.

Background: Lung cancer is considered to be the first place among the cancer-related deaths worldwide and demands novel strategies in the treatment of this life-threatening disorder. The aim of this review is to explore regulation of epithelial-to-mesenchymal transition (EMT) by long non-coding RNAs (lncRNAs) in lung cancer.

Introduction: LncRNAs can be considered as potential factors for targeting in cancer therapy, since they regulate a bunch of biological processes, e.g. cell proliferation, differentiation and apoptosis. The abnormal expression of lncRNAs occurs in different cancer cells. On the other hand, epithelial-to-mesenchymal transition (EMT) is a critical mechanism participating in migration and metastasis of cancer cells.

Method: Different databases including Googlescholar, Pubmed and Sciencedirect were used for collecting articles using keywords such as "LncRNA", "EMT", and "Lung cancer".

Result: There are tumor-suppressing lncRNAs that can suppress EMT and metastasis of lung cancer cells. Expression of such lncRNAs undergoes down-regulation in lung cancer progression and restoring their expression is of importance in suppressing lung cancer migration. There are tumor-promoting lncRNAs triggering EMT in lung cancer and enhancing their migration.

Conclusion: LncRNAs are potential regulators of EMT in lung cancer, and targeting them, both pharmacologically and genetically, can be of importance in controlling migration of lung cancer cells.
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http://dx.doi.org/10.2174/1568009621666210203110305DOI Listing
February 2021

Photo-mediated optimized synthesis of silver nanoparticles using the extracts of outer shell fibre of L. fruit and detection of its antioxidant, cytotoxicity and antibacterial potential.

Saudi J Biol Sci 2021 Jan 11;28(1):980-987. Epub 2020 Nov 11.

Research Institute of Biotechnology and Medical Converged Science, Dongguk University-Seoul, Goyang-si 10326, Republic of Korea.

Presently, photo-mediated optimized synthesis of SNPs (CS-AgNPs) was carried out with the help of aqueous extracts of coconut () outer shell fibre. Green synthesis of CS-AgNPs was undertaken under laboratory light conditions and characterized by several standard techniques such as UV-visible spectrophotometer (UV-Vis), X-ray diffraction pattern (XRD), Fourier transform infrared (FT-IR), and scanning electron microscopy (SEM) images and energy dispersive spectroscopy (EDX). UV-Vis spectra displayed a surface plasmon resonance peak at 468 nm equivalent to CS-AgNPs, and the FT-IR spectra confirmed the association of biological molecules from the extract in the synthesis process. The SEM image data confirmed the round and circular nature of CS-AgNPs. The EDX data presented the elemental configuration with a solid peak at 3 KeV that matched with the Ag. The synthesized CS-AgNPs exhibited substantial cytotoxicity potential against the HepG2 cells with (effective concentration (IC) value of 15.28 µg/ml along with robust antioxidant potential, with respect to its 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging (IC of 96.39 µg/ml) and reducing assay (IC of 209.96 µg/ml). The CS-AgNPs demonstrated encouraging antimicrobial potential against four different pathogenic bacteria and one Candida sp. with inhibition zone diameter ranged between 8.87 and 13.07 mm. Overall, the existing investigation suggested that CS-AgNPs can be an attractive, cost-effective, and environment-friendly candidate for its possible uses in the food, cosmetics, and therapeutic fields.
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http://dx.doi.org/10.1016/j.sjbs.2020.11.022DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7785444PMC
January 2021

Redox-sensitive nanoparticles based on xylan-lipoic acid conjugate for tumor targeted drug delivery of niclosamide in cancer therapy.

Carbohydr Res 2021 Jan 16;499:108222. Epub 2020 Dec 16.

Department of Polymer and Process Engineering, Indian Institute of Technology Roorkee, Saharanpur Campus, Paper Mill Road, Saharanpur, 247001, Uttar Pradesh, India. Electronic address:

In this study, novel redox-sensitive nanoparticles based on xylan-lipoic acid (Xyl-LA) conjugate were developed for tumor targeted delivery of niclosamide (Nic) in cancer therapy. The niclosamide loaded xylan-lipoic acid conjugate nanoparticles (Xyl-LA/Nic NPs) showed redox responsive behaviour in presence of reductive glutathione (GSH), which indicate their suitability for intracellular drug release. The obtained Xyl-LA/Nic NPs exhibited uniform particle size (196 ± 1.64 nm), high loading capacity (~28.6 wt %) and excellent blood compatibility. The anticancer activity of the Niclosamide and the Xyl-LA/Nic NPs against the colon carcinoma cell lines (HCT-15, Colo-320) were evaluated by MTT assay and the overall results indicate that the Xyl-LA/Nic NPs significantly enhanced the therapeutic efficiency of niclosamide in cancer therapy.
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http://dx.doi.org/10.1016/j.carres.2020.108222DOI Listing
January 2021

New Horizons in Hydrogels for Methotrexate Delivery.

Gels 2020 Dec 30;7(1). Epub 2020 Dec 30.

Biorefining and Advanced Materials Research Center, Scotland's Rural College (SRUC), Kings Buildings, West Mains Road, Edinburgh EH9 3JG, UK.

Since its first clinical application, methotrexate (MTX) has been widely used for the treatment of human diseases. Despite great advantages, some properties such as poor absorption, short plasma half-life and unpredictable bioavailability have led researchers to seek novel delivery systems to improve its characteristics for parenteral and oral administration. Recently, great attention has been directed to hydrogels for the preparation of MTX formulations. This review describes the potential of hydrogels for the formulation of MTX to treat cancer, rheumatoid arthritis, psoriasis and central nervous system diseases. We will delineate the state-of-the-art and promising potential of hydrogels for systemic MTX delivery as well as transdermal delivery of the drug-using hydrogel-based formulations.
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http://dx.doi.org/10.3390/gels7010002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7839000PMC
December 2020

Nanoporous Sodium Carboxymethyl Cellulose--poly (Sodium Acrylate)/FeCl Hydrogel Beads: Synthesis and Characterization.

Gels 2020 Dec 11;6(4). Epub 2020 Dec 11.

Department of Polymer and Process Engineering, Indian Institute of Technology Roorkee, Roorkee 247667, India.

Novel sodium carboxymethyl cellulose--poly (sodium acrylate)/Ferric chloride (CMC--PNaA/FeCl) nanoporous hydrogel beads were prepared based on the ionic cross-linking between CMC--PNaA and FeCl. The structure of CMC and CMC--PNaA were elucidated by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectroscopy, and the elemental composition was analyzed by energy dispersive X-ray analysis (EDX). The physicochemical properties of the CMC--PNaA/FeCl hydrogel beads were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and thermogravimetric analysis (TGA). The swelling percentage of hydrogel beads was studied at different time periods. The obtained CMC--PNaA/FeCl hydrogel beads exhibited a higher nanoporous morphology than those of CMC--PNaA and CMC beads. Furthermore, an AFM image of the CMC--PNaA/FeCl beads shows granule type topology. Compared to the CMC--PNaA (189 °C), CMC--PNaA/FeCl hydrogel beads exhibited improvement in thermal stability (199 °C). Furthermore, CMC--PNaA/FeCl hydrogel beads depicted a higher swelling percentage capacity of around 1452%, as compared to CMC--PNaA (1096%). Moreover, this strategy with preliminary results could be useful for the development of polysaccharide-based hybrid hydrogel beads for various potential applications.
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http://dx.doi.org/10.3390/gels6040049DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7768363PMC
December 2020

Is Transoral Robotic Surgery (TORS) for oropharyngeal squamous cell carcinoma being done more often than actually indicated?

Head Neck 2021 04 9;43(4):1376-1377. Epub 2020 Dec 9.

Department of Surgical Oncology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, India.

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http://dx.doi.org/10.1002/hed.26569DOI Listing
April 2021

Arsenic-induced differential expression of oxidative stress and secondary metabolite content in two genotypes of Andrographis paniculata.

J Hazard Mater 2021 03 29;406:124302. Epub 2020 Oct 29.

Chemical Sciences Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow 226015, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.

The present study explores the differential responses of two genotypes (APw: wild collection and AP: mass selection line) of A. paniculata against the three application rates of arsenic (42, 126, and 200 mg kg). The oxidative enzymes, As accumulation in different tissues, plant growth, and content of pharmacologically important ent-labdane-related diterpenes (ent-LRDs) of the two genotypes were evaluated in the study. Results demonstrated that As uptake significantly reduced plant biomass in APw and AP by 5-41.5% and 9-33% in a dose-response manner, respectively. The AP exhibited lower bioconcentration and translocation factors, higher As tolerance index, and higher content of ent-LRDs as compared to AP. As treatment induced a decrease in the sum of four metabolite content of AP (1.43 times) and an increase in that of AP (1.12 times) as compared to control. Likewise, variance in the production of 5,7,2',3'-tetramethoxyflavanone, and stress enzymes was also observed between APw and AP. The increase in the expression of ApCPS2 suggested its involvement in channeling of metabolic flux towards the biosynthesis of ent-LRDs under As stress.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124302DOI Listing
March 2021

Well-Defined Palladium N-Heterocyclic Carbene Complexes: Direct C-H Bond Arylation of Heteroarenes.

J Org Chem 2020 11 16;85(21):13983-13996. Epub 2020 Oct 16.

Synthetic Organic Chemistry Research Laboratory, Department of Chemistry, University of Delhi, Delhi 110007, India.

A series of palladium N-heterocyclic carbene (NHC) complexes of type -{(NHC)PdClL} (L = CHN, 3-ClCHN, and PPh) (-) have been developed as efficient precatalysts for direct C-H bond arylation of various heteroarenes. In particular, an in situ generated new NHC ligand derived from {1,3-di-(2,6-diethylphenyl)acenaphtho[1,2-] imidazolium} chloride () is used for the stabilization of the palladium metal center. Among the screened palladium precatalysts (-), the most active PEPPSI themed complex () was successfully employed toward direct C-H bond arylation of various heteroarenes and aryl bromides. A range of functional groups on aryl bromides as well as on heteroarenes sustained throughout the standard reaction conditions for easy access of various arylated heterocyclic compounds. Significantly, the utility of the protocol was demonstrated by the effective synthesis of a precursor of raloxifene, a selective estrogen receptor modulator.
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http://dx.doi.org/10.1021/acs.joc.0c02024DOI Listing
November 2020

Brachytherapy in India: Learning from the past and looking into the future.

Brachytherapy 2020 Nov - Dec;19(6):861-873. Epub 2020 Sep 15.

Department of Radiation Oncology, Apollo Cancer Institute, Hyderabad, India.

India has a longstanding tradition in the practice of brachytherapy and has actively contributed to the scientific literature by conducting prospective studies, clinical audits, developing innovative techniques, and performing randomized studies. Indian investigators have also contributed to international collaborative research, education, training programs along with guideline development for brachytherapy in cervix and head and neck cancers. The present article summarizes the key contributions to scientific literature, current infrastructure, skill set for brachytherapy, existing challenges, and strategy to further strengthen brachytherapy practice in the next decade.
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http://dx.doi.org/10.1016/j.brachy.2020.08.019DOI Listing
June 2021

What is the dosimetric impact of isotropic vs anisotropic safety margins for delineation of the clinical target volume in breast brachytherapy?

Brachytherapy 2021 Jan-Feb;20(1):155-162. Epub 2020 Sep 2.

Department of Radiation Oncology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, India.

Purpose: The purpose of the study was to report dosimetric differences for breast brachytherapy plans optimized for clinical target volume (CTV) generated using conventional isotropic expansion of tumor bed volume (TBV) and Groupe Européen de Curiethérapie-European Society for Radiotherapy and Oncology (GEC-ESTRO) recommendations to expand the TBV anisotropically to achieve a total safety margin of 2 cm (resection margin size + added safety margin).

Methods: Institutional records of 100 patients who underwent accelerated partial breast irradiation using multicatheter interstitial brachytherapy from May 2015 to March 2020 were reviewed retrospectively. Two sets of CT-based plans were made, one with 1-cm isotropic margins around the tumor bed (CTV_ISO) and the other with anisotropic margins (CTV_GEC). Plans were evaluated and compared using the American Brachytherapy Society and GEC-ESTRO guidelines.

Results: The median TBV was 36.97 cc. The median margin widths were as follows: anterior 1.2, posterior 1.0, superior 1.0, inferior 0.9, medial 1.2, and lateral 1.2 cm. The mean tumor bed coverage index was 0.94; 0.93 [p.066], the CTV coverage index 0.86; 0.84 [p 0.001], the dose homogeneity index (DHI) 0.77; 0.75 [p < 0.001] and the conformity index 0.66; 0.64 [p < 0.001] in CTV_ISO and CTV_GEC plans, respectively. In smaller volume implants (TBV< 35 cc), the DHI was 0.76; 0.75 [p 0.008] and the conformity index was 0.66; 0.62 [p < 0.001], whereas in larger volumes >35 cc, the CTV coverage index was 0.86; 0.84 [p 0.003] and the DHI 0.78; 0.76 [p 0.001] in CTV_ISO and CTV_GEC plans, respectively.

Conclusions: In this cohort of patients who underwent accelerated partial breast irradiation, plans with anisotropic margins had lower conformity, the impact of which was predominantly seen in smaller implants. Rest of the dosimetric constraints were achieved in both the plans as per the American Brachytherapy Society and GEC-ESTRO guidelines.
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http://dx.doi.org/10.1016/j.brachy.2020.06.019DOI Listing
August 2021
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