78 results on '"Naveen Thakur"'
Search Results
2. Ocimum sanctum-mediated co/cu/zn-doped magnesium oxide nanoparticles: Photocatalytic, antibacterial, and antioxidant properties for environmental remediation
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Dimpal Chauhan, Ravi Kumar, Naveen Thakur, Mahender Singh, and Kuldeep Kumar
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MgO nanoparticles ,Biosynthesis ,Ocimum sanctum ,Photocatalysis ,Biological properties ,Technology - Abstract
This research intends to formulate Ocimum sanctum mediated pure and transition metal (Co2+/Cu2+/Zn2+) doped magnesium oxide nanoparticles (MgO NPs). The cubic structure of so synthesized MgO NPs was confirmed by XRD analysis. As per UV–visible spectral analysis, band gap (Eg) is tuned upon doping; doping with Co, Cu and Zn, their respective Eg are 1.65 eV, 1.96 eV and 3.66 eV in relation to MgO, Eg = 3.50 eV. The average particle size decreased from 17 nm for MgO NPs to 8–13 nm for doped MgO NPs, based on TEM analysis. EDX and XPS analysis verified the presence of Mg, O and dopants, Co, Cu and Zn in synthesized NPs. SEM investigations showed that NPs are agglomerated and spherical. Zn–MgO NPs outperform Co/Cu doped MgO NPs in their photocatalytic efficacy and comparative degradation of methyl orange (MO) and malachite green (MG) dyes confirmed that they are more efficient in degrading MG. Antibacterial investigation revealed that Cu and Zn doped MgO NPs are efficient antibacterial agents against B. subtilis and E. coli than MgO NPs. In this study, Co–MgO NPs were ineffective as antibacterial agents. S. aureus was found resistant to all NPs. Using the DPPH radical scavenging technique, these biosynthesized nanoparticles displayed 62–69 % antioxidant activity.
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- 2024
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3. Anti-HIV drugs (emtricitabine and lamivudine) mediated micellization behavior of anionic and cationic surfactants: A thermodynamic investigation
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Richa Sharma, Suvarcha Chauhan, Naveen Thakur, and Kuldeep Kumar
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Anti-HIV drug ,Aggregation property ,Conventional surfactant ,Thermodynamics ,UV-Visible spectroscopy ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Aggregation behavior of conventional surfactants; SDS (anionic) and CTAB (cationic) in aqueous medium has been investigated in the presence of anti-HIV drugs; Emtricitabine (ECT) and Lamivudine (LMV) using conductometry, UV–Visible spectroscopy, and fluoroscence measurements over a temperature range of T = (298.15–313.15) K. The CMC values calculated from the conventional study i.e. conductance measurements corroborate very well with those obtained from spectroscopic techniques i.e. UV–Visible spectroscopy and fluorometry. The calculated CMC values have been used to determine thermodynamic parameters such as standard changes in enthalpy of micellization (ΔHmo), entropy of micellization (ΔSmo) and free energy of micellization (ΔGmo) using pseudo-phase separation model. These parameters have been analyzed in terms of the hydrophobic-hydrophilic interactions present in the surfactant-water-drug ternary system. It has been observed from the thermodynamic analysis that both the drugs favor micellization of studied ionic surfactants (SDS and CTAB) in aqueous medium, with Lamivudine exhibiting a more pronounced effect. Further, the micellar stability of studied systems has been analyzed in terms of enthalpy-entropy compensation graphs. This in-depth exploration of anti-HIV drug-surfactant interactions holds promising implications for enhancing pharmaceutical formulations in the context of HIV infection diseases.
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- 2024
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4. Single-molecule visualization of human A2A adenosine receptor activation by a G protein and constitutively activating mutations
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Shushu Wei, Niloofar Gopal Pour, Sriram Tiruvadi-Krishnan, Arka Prabha Ray, Naveen Thakur, Matthew T. Eddy, and Rajan Lamichhane
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Biology (General) ,QH301-705.5 - Abstract
Abstract Mutations that constitutively activate G protein-coupled receptors (GPCRs), known as constitutively activating mutations (CAMs), modify cell signaling and interfere with drugs, resulting in diseases with limited treatment options. We utilize fluorescence imaging at the single-molecule level to visualize the dynamic process of CAM-mediated activation of the human A2A adenosine receptor (A2AAR) in real time. We observe an active-state population for all CAMs without agonist stimulation. Importantly, activating mutations significantly increase the population of an intermediate state crucial for receptor activation, notably distinct from the addition of a partner G protein. Activation kinetics show that while CAMs increase the frequency of transitions to the intermediate state, mutations altering sodium sensitivity increase transitions away from it. These findings indicate changes in GPCR function caused by mutations may be predicted based on whether they favor or disfavor formation of an intermediate state, providing a framework for designing receptors with altered functions or therapies that target intermediate states.
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- 2023
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5. Phyto-fabrication of CuO–Co3O4 nanocomposites for antibacterial, photocatalytic and antioxidant evaluations: An in-vitro investigation
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Ravi Kumar, Kuldeep Kumar, and Naveen Thakur
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Antibacterial action ,CuO–Co3O4 nanocomposite ,Ipomoea carnea ,Microwave-assisted green method ,Photocatalytic property ,Scavenging activity ,Technology - Abstract
In this current investigation, we elucidated the microwave-assisted green synthesis of 90:10, 80:20, and 70:30 CuO–Co3O4 nanocomposites (NCs) from Ipomoea carnea leaf extract, manifesting their remarkable antibacterial, photocatalytic, and antioxidant capabilities. The spectroscopic techniques of XRD, SEM, EDX, TEM, FTIR, and UV–visible spectroscopy were employed to validate the formation of the synthesized NCs. SEM and TEM images revealed distinctive snowball-rod and distorted spherical structures in the synthesized nanocomposites, with average particle sizes of 33.36, 26.17, and 29.10 nm. The estimated energy band gap values were 1.20, 1.40, and 1.50 eV for the respective nanocomposites. The well diffusion method was utilized to explore the zone of inhibition (ZOI) against bacteria, namely Bacillus subtilis, Staphylococcus aureus, and Escherichia coli. The nanocomposites, specifically the 90:10 and 80:20 CuO–Co3O4 blends, exhibited a noteworthy Zone of Inhibition (ZOI) during testing against B. subtilis, with approximate values of 34.76 ± 0.23 and 33.33 ± 0.32 mm, respectively. Furthermore, the photocatalytic potential has been investigated against the dyes Malachite green (MG) and Congo red (CR). Notably, the 90:10 NCs displayed an exceptional photodegradation rate of 97.69 % for MG and 95 % for CR within a mere 45 min. Moreover, the 70:30 NCs exhibited a commendable radical scavenging activity of approximately 97.53 % at a concentration of 800 μg/mL, while ascorbic acid, used as a standard, displayed a scavenging activity of 98.63 %. These investigations unveil the environmentally friendly, innovative, and cost-effective attributes of CuO–Co3O4 NCs derived from Ipomoea carnea leaf extract, which demonstrated excellent antibacterial, photocatalytic, and antioxidant properties.
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- 2024
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6. Tinospora cordifolia and polyvinylpyrrolidone encapsulated dual doped Ni-Cu TiO2 emerging nanocatalyst for the removal of organic dyes from wastewater and its free radical assay activity
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Nikesh Thakur, Ashwani Kumar, and Naveen Thakur
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Degradation ,Dual doped ,Encapsulation ,Scavenging ,Technology - Abstract
In this study, a microwave-assisted method was used to encapsulate dual doped nickel-copper titanium dioxide (TiO2) nanoparticles (Ni-Cu TNPs) with polymer polyvinylpyrrolidone (PVP) and plant Tinospora Cordifolia (TC). The catalytic efficiency of encapsulated TNPs was performed through photocatalytic activity against Methyl Orange (MO) and Methylene Blue (MB) dyes as considered as water pollutants released by textiles industries. Also, these encapsulated TNPs were incubated in scavenging activity to eliminate the free radicals 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The physicochemical properties of the encapsulated TNPs were analyzed using different characterization techniques. X-Ray Diffraction (XRD revealed that the encapsulated dual doped Ni-Cu TNPs had a tetragonal crystal lattice structure. The scanning electron microscopy (SEM) confirms the spherical morphology of encapsulated dual doped Ni-Cu TNPs with an average particle size ranging from 33 to 41 nm. The bandgap of the encapsulated dual doped Ni-Cu TNPs was found to be between 3.47 and 3.54 eV. Under UV radiation, the photocatalytic activity was performed with using control experiment and using encapsulated dual doped Ni-Cu TNPs against MO and MB dyes. The rate of degradation reached up to 99% for both dyes on increasing with an increase in TNPs catalyst dosage. Also, the encapsulated dual doped Ni-Cu TNPs demonstrated antioxidant activity of up to 93% against the DPPH assay.
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- 2023
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7. Anionic phospholipids control mechanisms of GPCR-G protein recognition
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Naveen Thakur, Arka P. Ray, Liam Sharp, Beining Jin, Alexander Duong, Niloofar Gopal Pour, Samuel Obeng, Anuradha V. Wijesekara, Zhan-Guo Gao, Christopher R. McCurdy, Kenneth A. Jacobson, Edward Lyman, and Matthew T. Eddy
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Science - Abstract
In cell membranes, lipids are ubiquitous regulators of protein function. Here, Thakur et al. observe anionic phospholipids impact the conformational dynamics of a class A human GPCR.
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- 2023
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8. Antibacterial Potential of Zinc Oxide Nanoparticles Synthesized using Aloe vera (L.) Burm.f.: A Green Approach to Combat Drug Resistance
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Chainika Khatana, Ashwani Kumar, Mashael W. Alruways, Nazam Khan, Naveen Thakur, Dinesh Kumar, and Amita Kumari
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aloe vera ,zinc oxide nanoparticles ,green synthesis ,characterization ,microbial pathogens ,Microbiology ,QR1-502 - Abstract
Microbial infections and antibiotic resistance are some of the prime factors that are ascribed to endanger human health. Several reports have highlighted that drug-resistant pathogens assist in the etiology of various chronic diseases and lead to fatality. The present study deciphered the role of zinc oxide nanoparticles (ZnO NPs) as therapeutics against selected bacterial strains. The plant-based technique was followed to synthesize ZnO NPs. The synthesis was confirmed with different techniques viz. X-ray diffraction, transmission electron microscope (interplanar spacing at 0.126 nm), scanning electron microscope (flower-like structure), and Fourier transform infrared spectroscopy. The antibacterial analysis revealed that ZnO NPs inhibited the growth of all tested strains (Escherichia coli, Staphylococcus aureus, Salmonella typhi, Bacillus subtilis, and Klebsiella pneumoniae) to a greater extent (MIC ranged between 0.013±0.004-0.0625±0 mg/mL) as compared with ZnO compound (Bulk material). In the present study, ZnO NPs were produced in a cost-effective and environmentally sustainable way using a green process and can be used as a remedy for drug-resistant pathogens.
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- 2021
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9. A comparative study of interfacial environments in lipid nanodiscs and vesicles
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Xiao You, Naveen Thakur, Arka Prabha Ray, Matthew T. Eddy, and Carlos R. Baiz
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Physics ,QC1-999 ,Biology (General) ,QH301-705.5 - Abstract
Membrane protein conformations and dynamics are driven by the protein-lipid interactions occurring within the local environment of the membrane. These environments remain challenging to accurately capture in structural and biophysical experiments using bilayers. Consequently, there is an increasing need for realistic cell-membrane mimetics for in vitro studies. Lipid nanodiscs provide certain advantages over vesicles for membrane protein studies. Nanodiscs are increasingly used for structural and spectroscopic characterization of membrane proteins. Despite the common use of nanodiscs, the interfacial environments of lipids confined to a ∼10-nm diameter area have remained relatively underexplored. Here, we use ultrafast two-dimensional infrared spectroscopy and temperature-dependent infrared absorption measurements of the ester carbonyls to compare the interfacial hydrogen bond structure and dynamics in lipid nanodiscs of varying lipid compositions and sizes with ∼100-nm vesicles. We examine the effects of lipid composition and nanodisc size. We found that nanodiscs and vesicles share largely similar lipid-water H-bond environments and interfacial dynamics. Differences in measured enthalpies of H-bonding suggest that H-bond dynamics in nanodiscs are modulated by the interaction between the annular lipids and the scaffold protein.
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- 2022
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10. Production of human A2AAR in lipid nanodiscs for 19F-NMR and single-molecule fluorescence spectroscopy
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Naveen Thakur, Shushu Wei, Arka Prabha Ray, Rajan Lamichhane, and Matthew T. Eddy
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Biophysics ,Single-molecule Assays ,Cell Membrane ,Molecular/Chemical Probes ,Protein Biochemistry ,Protein expression and purification ,Science (General) ,Q1-390 - Abstract
Summary: We describe production of the human A2A adenosine receptor (A2AAR), a class A G protein-coupled receptor (GPCR) for 19F-NMR and single-molecule fluorescence (SMF) spectroscopy. We explain in detail steps shared between the two sample preparation strategies, including expression and isolation of A2AAR and assembly of A2AAR in lipid nanodiscs and procedures for incorporation of either 19F-NMR or fluorescence probes. Protocols for SMF experiments include sample setup, data acquisition, data processing, and error analysis.For complete details on the use and execution of this protocol, please refer to Wei et al. (2022) and Sušac et al. (2018). : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.
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- 2022
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11. Ebolavirus Species-Specific Interferon Antagonism Mediated by VP24
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Palaniappan Ramanathan, Bersabeh Tigabu, Rodrigo I. Santos, Philipp A. Ilinykh, Natalia Kuzmina, Olivia A. Vogel, Naveen Thakur, Hamza Ahmed, Chao Wu, Gaya K. Amarasinghe, Christopher F. Basler, and Alexander Bukreyev
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Ebolavirus ,VP24 ,immune evasion ,STAT1 ,Microbiology ,QR1-502 - Abstract
Members of the Ebolavirus genus demonstrate a marked differences in pathogenicity in humans with Ebola (EBOV) being the most pathogenic, Bundibugyo (BDBV) less pathogenic, and Reston (RESTV) is not known to cause a disease in humans. The VP24 protein encoded by members of the Ebolavirus genus blocks type I interferon (IFN-I) signaling through interaction with host karyopherin alpha nuclear transporters, potentially contributing to virulence. Previously, we demonstrated that BDBV VP24 (bVP24) binds with lower affinities to karyopherin alpha proteins relative to EBOV VP24 (eVP24), and this correlated with a reduced inhibition in IFN-I signaling. We hypothesized that modification of eVP24-karyopherin alpha interface to make it similar to bVP24 would attenuate the ability to antagonize IFN-I response. We generated a panel of recombinant EBOVs containing single or combinations of point mutations in the eVP24-karyopherin alpha interface. Most of the viruses appeared to be attenuated in both IFN-I-competent 769-P and IFN-I-deficient Vero-E6 cells in the presence of IFNs. However, the R140A mutant grew at reduced levels even in the absence of IFNs in both cell lines, as well as in U3A STAT1 knockout cells. Both the R140A mutation and its combination with the N135A mutation greatly reduced the amounts of viral genomic RNA and mRNA suggesting that these mutations attenuate the virus in an IFN-I-independent attenuation. Additionally, we found that unlike eVP24, bVP24 does not inhibit interferon lambda 1 (IFN-λ1), interferon beta (IFN-β), and ISG15, which potentially explains the lower pathogenicity of BDBV relative to EBOV. Thus, the VP24 residues binding karyopherin alpha attenuates the virus by IFN-I-dependent and independent mechanisms.
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- 2023
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12. New Insights Into the Function of Flavohemoglobin in Mycobacterium tuberculosis: Role as a NADPH-Dependent Disulfide Reductase and D-Lactate-Dependent Mycothione Reductase
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Naveen Thakur, Amar Nath Sharma, Mangesh Dattu Hade, Ajay Chhaya, Ashwani Kumar, Ravinder Singh Jolly, and Kanak L. Dikshit
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flavohemoglobin ,Mycobacterium tuberculosis ,FAD ,D-lactate ,thioredoxin reductase ,oxidative stress ,Microbiology ,QR1-502 - Abstract
Mycobacterium tuberculosis (Mtb) produces an unconventional flavohemoglobin (MtbFHb) that carries a FAD-binding site similar to D-lactate dehydrogenases (D-LDH) and oxidizes D-lactate into pyruvate. The molecular mechanism by which MtbFHb functions in Mtb remains unknown. We discovered that the D-LDH-type FAD-binding site in MtbFHb overlaps with another FAD-binding motif similar to thioredoxin reductases and reduces DTNB in the presence of NADPH similar to trxB of Mtb. These results suggested that MtbFHb is functioning as a disulfide oxidoreductase. Interestingly, D-lactate created a conformational change in MtbFHb and attenuated its ability to oxidize NADPH. Mass spectroscopy demonstrated that MtbFHb reduces des-myo-inositol mycothiol in the presence of D-lactate unlike NADPH, indicating that D-lactate changes the specificity of MtbFHb from di-thiol to di-mycothiol. When M. smegmatis carrying deletion in the fhbII gene (encoding a homolog of MtbFHb) was complemented with the fhb gene of Mtb, it exhibited four- to fivefold reductions in lipid peroxidation and significant enhancement in the cell survival under oxidative stress. These results were corroborated by reduced lipid peroxidation and enhanced cell survival of wild-type M. smegmatis after overexpression of the fhb gene of Mtb. Since D-lactate is a by-product of lipid peroxidation and MtbFHb is a membrane-associated protein, D-lactate-mediated reduction of mycothiol disulfide by MtbFHb may uniquely equip Mtb to relieve the toxicity of D-lactate accumulation and protect the cell from oxidative damage, simultaneously balancing the redox environment under oxidative stress that may be vital for the pathogenesis of Mtb.
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- 2022
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13. Nanotechnology Interventions in the Management of COVID-19: Prevention, Diagnosis and Virus-Like Particle Vaccines
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Acharya Balkrishna, Vedpriya Arya, Akansha Rohela, Ashwani Kumar, Rachna Verma, Dinesh Kumar, Eugenie Nepovimova, Kamil Kuca, Naveen Thakur, Nikesh Thakur, and Pankaj Kumar
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SARS-CoV-2 ,COVID-19 ,diagnosis ,virus-like particle vaccines ,prevention ,Medicine - Abstract
SARS-CoV-2 claimed numerous lives and put nations on high alert. The lack of antiviral medications and the small number of approved vaccines, as well as the recurrence of adverse effects, necessitates the development of novel treatment ways to combat COVID-19. In this context, using databases such as PubMed, Google Scholar, and Science Direct, we gathered information about nanotechnology’s involvement in the prevention, diagnosis and virus-like particle vaccine development. This review revealed that various nanomaterials like gold, polymeric, graphene and poly amino ester with carboxyl group coated magnetic nanoparticles have been explored for the fast detection of SARS-CoV-2. Personal protective equipment fabricated with nanoparticles, such as gloves, masks, clothes, surfactants, and Ag, TiO2 based disinfectants played an essential role in halting COVID-19 transmission. Nanoparticles are used not only in vaccine delivery, such as lipid nanoparticles mediated transport of mRNA-based Pfizer and Moderna vaccines, but also in the development of vaccine as the virus-like particles elicit an immune response. There are now 18 virus-like particle vaccines in pre-clinical development, with one of them, developed by Novavax, reported being in phase 3 trials. Due to the probability of upcoming COVID-19 waves, and the rise of new diseases, the future relevance of virus-like particles is imperative. Furthermore, psychosocial variables linked to vaccine reluctance constitute a critical problem that must be addressed immediately to avert pandemic.
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- 2021
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14. A case report on buccal mucosa graft for upper ureteral stricture repair
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Vilas Pandurang Sabale, Naveen Thakur, Sharad Kumar Kankalia, and Vikram Pramod Satav
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Buccal mucosa graft ,reconstruction ,ureteric stricture ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Management of ureteric stricture especially long length upper one-third poses a challenging job for most urologists. With the successful use of buccal mucosa graft (BMG) for stricture urethra leads the foundation for its use in ureteric stricture also. A 35-year-old male diagnosedcase of left upper ureteric stricture, postureteroscopy with left percutaneous nephrostomy (PCN) in situ. Cysto-retrograde pyelography and nephrostogram done simultaneously suggestive of left upper ureteric stricture of 3 cm at L3 level. On exploration, diseased ureteral segment exposed, BMG harvested and sutured as onlay patch graft with supportive omental wrap. The treatment choice for upper ureteric long length stricture is inferior nephropexy, autotransplantation, or bowel interposition. With PCN in situ, inferior nephropexy becomes technically difficult, other two are morbid procedures. Use of BMG in this situation is technically better choice with all the advantages of buccal mucosa. Onlay BMG for ureteral stricture is technically easy, less morbid procedure and can be important choice in future.
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- 2016
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15. Male urethral diverticulum uncommon entity: Our experience
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Naveen Thakur, Vilas Pandurang Sabale, Deepak Mane, and Abhirudra Mullay
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Retrograde urethrogram ,urethral diverticulum ,urethroplasties ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Out pouching of the urethral wall could be congenital or acquired. Male urethral diverticulum (UD) is a rare entity. We present 2 cases of acquired and 1 case of congenital male UD. Case 1A: 40 year male presented with SPC and dribbling urine. Clinically he had hard perineal swelling. RGU revealed large diverticulum in proximal bulbar, irregular narrow distal urethra and stricture just beyond diverticulum. Managed with perineal exploration, stone removal, diverticulum repair and urethroplasty using excess diverticular wall. Case 2A: 30 year male with obstructive lower urinary tract symptoms (LUTS). Retrograde urethrogram (RGU) revealed bulbar urethral diverticulum akin to anterior urethral valve, managed endoscopically. 1 year follow up urine stream satisfactory. Case 3A: 27 year male previously operated large proximal bulbar urethral stone with incontinence. RGU large proximal bulbar UD with wide open sphincter. Treated with excision of excess diverticular wall and penile clamp with pelvic exercises for incontinence. Congenital UD develops due to imperfect closure of urethral fold, Acquired UDs occurs secondary to stricture, infection, trauma, long standing impacted urethral stones or scrotal / skin flap urethroplasties. RGU and MCU are the best diagnostic technique to confirm and characterize the UD. Urethral diverticulectomy with urethral reconstruction is the recommended treatment for UD. UD is a rare entity. Especially in males, congenital are even more rare. Management should be individualized. Surgery can involve innovation and/or surgical modifications. We used excess diverticular flap for stricture urethroplasty in one case.
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- 2016
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16. Comparative evaluation of upper versus lower calyceal approach in percutaneous nephrolithotomy for managing complex renal calculi
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Rohit Singh, S P Kankalia, Vilas Sabale, Vikram Satav, Deepak Mane, Abhirudra Mulay, Bhupender Kadyan, and Naveen Thakur
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Percutaneous nephrolithotomy ,staghorn ,supracostal puncture ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Introduction: Percutaneous nephrolithotomy (PCNL) is the treatment of choice for staghorn and large renal stones. The success of PCNL is highly related to optimal renal access. Upper calyceal puncture being more difficult and more demanding have relatively few studies presented. Aims and Objectives: This prospective study was carried out to evaluate the effectiveness and safety of upper calyceal versus lower calyceal puncture for the removal of complex renal stones through PCNL. Materials and Methods: A total of 94 patients underwent PCNL for complex renal stone in our institute. Fifty-one of them underwent lower calyceal, while 43 underwent upper calyceal puncture. The two approaches are compared as per total duration of surgery, intraoperative blood loss, infundibular/pelvic tear, rate of complete clearance and rate of postoperative complications (pulmonary, bleeding, fever and sepsis, etc.). Observation and Results: In our study, the success rate was 76.47% for those in the lower, 90.70% for those in the upper calyceal access group. Thoracic complications (hydrothorax) occurred to 1 patient in upper calyceal supracostal access group. Bleeding requiring blood transfusion happened to 5 patients in lower calyceal access and 1 in upper calyceal group. Conclusion: In our study for the management of complex renal calculi, we conclude that in a previously unoperated kidney, upper calyceal puncture through subcostal or supra 12 th rib is a feasible option minimizing lung/pleural rupture and gives a better clearance rate. We suggest that with due precautions, there should not be any hesitation for upper calyceal puncture in indicated patients.
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- 2015
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17. Multifunctional properties of microwave assisted CuO/Cu2O-ZnO mixed metal oxide nanocomposites
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Ravi Kumar, Kuldeep Kumar, Saurabh Sharma, Nikesh Thakur, and Naveen Thakur
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Electrical and Electronic Engineering ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Published
- 2023
18. Dual mechanisms of cholesterol-GPCR interactions that depend on membrane phospholipid composition
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Arka Prabha Ray, Naveen Thakur, Niloofar Gopal Pour, and Matthew T. Eddy
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Structural Biology ,Molecular Biology - Published
- 2023
19. Degradation of malachite green dye by capping polyvinylpyrrolidone and Azadirachta indica in hematite phase of Ni doped Fe2O3 nanoparticles via co-precipitation method
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Naveen Thakur, Pankaj Kumar, Ashwani Tapwal, and Kamal Jeet
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In the present research, a chemical co-precipitation approach has been used to approach the synthesis, characterization, and photocatalytic applicability of Ni-doped α-Fe2O3 (hematite) nanoparticles. Biosynthesized iron oxide nanoparticles (IONPs) were successfully synthesized using a non-toxic leaf extract of the Azadirachta indica (AI) plant (neem) as a reducing and stabilizing agent. X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy, FT-IR spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, and vibrating sample magnetometer (VSM) have all been used to examine the synthesized materials. All of the produced NPs contain only the nanocrystalline hematite phase, according to XRD measurements. The morphology studies of the Ni-doping hematite nanoparticles, as demonstrated by TEM and SEM. The phase purity and phonon modes of the prepared nanoparticles are confirmed by Raman spectroscopy. The UV-Vis absorption tests show also that value of the band gap increases together with the reduction in particle size, going from 2.26 eV for chemical α-Fe2O3 to 2.5 eV for green Ni-doped α-Fe2O3 nanoparticles. Additionally, it was clear from the magnetic characteristics that all of the samples behaved ferromagnetically at ambient temperatures. On the other side, malachite green (MG) dye was used as a surrogate industrial wastewater dye in order to study the photocatalytic efficiency of Ni-doped α-Fe2O3 particles. The pure/green Ni-doped α-Fe2O3 NPs showed that after 70 minutes of exposure, 92% of the MG had become discolored.
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- 2023
20. Synthesis and characterization of N,N′-Di-1-naphthyl-N,N′-diphenylbenzidine as a hole-transporting layer (HTL) for Perovskite solar cell applications
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Harpreet Kaur Brar, Naveen Thakur, Sukhwinder Singh Brar, and Dinesh Pathak
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Statistical and Nonlinear Physics ,Condensed Matter Physics - Abstract
In this communication, we report a typical structural, optical and electrical analysis of thin films of hole transport material (HTM) based on aromatic phenyl benzidine derivative (N,N[Formula: see text]-Di-1-naphthyl-N,N[Formula: see text]-diphenylbenzidine) deposited by thermal evaporation technique onto the glass substrate. The effect of substrate temperature on the physical and electronic properties of these organic thin films for perovskite solar cells (PSCs) applications has been investigated. The films have been characterized by FTIR, XRD, SEM, UV–Vis spectroscopy and photoluminescence spectroscopy. Electrical conductivity and activation energies of films have also been calculated. From FTIR data of fabricated films and powder, it was found that the compound does not decompose during the thermal evaporation process as observed vibrational frequencies of films and the powder are the same. From the results, it has been determined that the substrate temperature has a huge impact on the physical structure and has also influenced the optical, electrical properties of the films. As observed from the studies it appears that these amorphous films with bandgap near to 3[Formula: see text]eV and suitable conductivity have potential for photovoltaics layer devices. From this study, it can be concluded that N,N[Formula: see text]-Di-1-naphthyl-N,N[Formula: see text]-diphenylbenzidine can be used as an active hole transport layer in PSCs.
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- 2023
21. Tinospora cordifolia mediated eco-friendly synthesis of Cobalt doped TiO2 NPs for degradation of organic methylene blue dye
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Nikesh Thakur, Naveen Thakur, Kuldeep Kumar, and Ashwani Kumar
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General Medicine - Published
- 2023
22. Photodegradation of methyl orange dye by using Azadirachta indica and chemically mediated synthesized cobalt doped α-Fe2O3 NPs through co-precipitation method
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Pankaj Kumar, Naveen Thakur, Kuldeep Kumar, and Kamal Jeet
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General Medicine - Published
- 2023
23. Robust stability, half metallic Ferromagnetism and structural properties of Co2RhSi, and Co2RuSi Heusler compounds-A first principles approach
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Ashwani Kumar, Tarun Chandel, null Diwaker, and Naveen Thakur
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General Medicine - Published
- 2022
24. Phosphatidyl serine preconditions the A2AAR for G-protein coupling via a conserved motif on TM6 and TM7
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Liam M. Sharp, Matthew T. Eddy, Naveen Thakur, Arka Prabha Ray, and Edward R. Lyman
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Biophysics - Published
- 2023
25. Phytoantioxidant Functionalized Nanoparticles: A Green Approach to Combat Nanoparticle-Induced Oxidative Stress
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Rachna Verma, Naveen Thakur, Kamil Kuca, Acharya Balkrishna, Ondrej Krejcar, Akansha Rohela, Eugenie Nepovimova, Dinesh Kumar, Vedpriya Arya, and Ashwani Kumar
- Subjects
Aging ,QH573-671 ,Plant Extracts ,Chemistry ,Phytochemicals ,Metal Nanoparticles ,Nanoparticle ,Nanotechnology ,Context (language use) ,Free Radical Scavengers ,Review Article ,Cell Biology ,General Medicine ,medicine.disease_cause ,Biochemistry ,Antioxidants ,Oxidative damage ,Oxidative Stress ,Cosmetic ingredient ,Functionalized nanoparticles ,medicine ,Animals ,Humans ,Cytology ,Oxidative stress - Abstract
Nanotechnology is gaining significant attention, with numerous biomedical applications. Silver in wound dressings, copper oxide and silver in antibacterial preparations, and zinc oxide nanoparticles as a food and cosmetic ingredient are common examples. However, adverse effects of nanoparticles in humans and the environment from extended exposure at varied concentrations have yet to be established. One of the drawbacks of employing nanoparticles is their tendency to cause oxidative stress, a significant public health concern with life-threatening consequences. Cardiovascular, renal, and respiratory problems and diabetes are among the oxidative stress-related disorders. In this context, phytoantioxidant functionalized nanoparticles could be a novel and effective alternative. In addition to performing their intended function, they can protect against oxidative damage. This review was designed by searching through various websites, books, and articles found in PubMed, Science Direct, and Google Scholar. To begin with, oxidative stress, its related diseases, and the mechanistic basis of oxidative damage caused by nanoparticles are discussed. One of the main mechanisms of action of nanoparticles was unearthed to be oxidative stress, which limits their use in humans. Secondly, the role of phytoantioxidant functionalized nanoparticles in oxidative damage prevention is critically discussed. The parameters for the characterization of nanoparticles were also discussed. The majority of silver, gold, iron, zinc oxide, and copper nanoparticles produced utilizing various plant extracts were active free radical scavengers. This potential is linked to several surface fabricated phytoconstituents, such as flavonoids and phenols. These phytoantioxidant functionalized nanoparticles could be a better alternative to nanoparticles prepared by other existing approaches.
- Published
- 2021
26. Effect of natural radionuclide’s in the environment along the Jwalamukhi thrust of Himachal Pradesh, North West Himalayas, India
- Author
-
Naveen Thakur, Jitender Kumar, Manpreet Kaur, Rohit Mehra, Ajay Kumar, and Reetika Bhadwal
- Subjects
Radionuclide ,Environmental Engineering ,Soil test ,chemistry.chemical_element ,Radon ,Thrust ,General Medicine ,Hazard ,Natural (archaeology) ,Radium ,chemistry ,Geochemistry and Petrology ,North west ,Environmental Chemistry ,Environmental science ,Physical geography ,General Environmental Science ,Water Science and Technology - Abstract
This research paper is devoted to measure the activity contents of natural radionuclide, like, radium (226Ra), thorium (232Th) and potassium (40K) in the soil gathered along the Jwalamukhi thrust of Himachal Pradesh, North Western Himalayas, India. NaI(Tl) Scintillator detector was utilized for the estimation of activity content. The activity concentration of 226Ra, 232Th and 40K for some of the soil samples have been observed to be above the global normal mean values. The outcomes acquired for indoor and outdoor effective dosage are well below the normal international and national proposed results. The determined values of external hazard (Hex) for studied locations are less than unity, therefore; samples assembled from these regions are safe from a health hazard point of view and can be utilized as a construction purposes without producing any radio-logical hazard to human beings. The average estimations of radium equivalent activity were found to be within the limits suggested by Organization for Economic Cooperation and Development (OECD). Radon (222Rn) and thoron (220Rn) exhalation rates have also been calculated and discussed.
- Published
- 2021
27. Antibacterial Potential of Zinc Oxide Nanoparticles Synthesized using Aloe vera (L.) Burm.f.: A Green Approach to Combat Drug Resistance
- Author
-
Mashael W. Alruways, Dinesh Kumar, Ashwani Kumar, Nazam Khan, Chainika Khatana, Amita Kumari, and Naveen Thakur
- Subjects
biology ,Chemistry ,green synthesis ,zinc oxide nanoparticles ,Nanoparticle ,chemistry.chemical_element ,Zinc ,Drug resistance ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Microbiology ,QR1-502 ,Aloe vera ,aloe vera ,characterization ,microbial pathogens ,Biotechnology ,Nuclear chemistry - Abstract
Microbial infections and antibiotic resistance are some of the prime factors that are ascribed to endanger human health. Several reports have highlighted that drug-resistant pathogens assist in the etiology of various chronic diseases and lead to fatality. The present study deciphered the role of zinc oxide nanoparticles (ZnO NPs) as therapeutics against selected bacterial strains. The plant-based technique was followed to synthesize ZnO NPs. The synthesis was confirmed with different techniques viz. X-ray diffraction, transmission electron microscope (interplanar spacing at 0.126 nm), scanning electron microscope (flower-like structure), and Fourier transform infrared spectroscopy. The antibacterial analysis revealed that ZnO NPs inhibited the growth of all tested strains (Escherichia coli, Staphylococcus aureus, Salmonella typhi, Bacillus subtilis, and Klebsiella pneumoniae) to a greater extent (MIC ranged between 0.013±0.004-0.0625±0 mg/mL) as compared with ZnO compound (Bulk material). In the present study, ZnO NPs were produced in a cost-effective and environmentally sustainable way using a green process and can be used as a remedy for drug-resistant pathogens.
- Published
- 2021
28. TiO2 nanofibers fabricated by electrospinning technique and degradation of MO dye under UV light
- Author
-
Viplove Bhullar, Kuldeep Kumar, Nikesh Thakur, Saurabh Sharma, Davinder Pal Sharma, Dinesh Pathak, Naveen Thakur, and Aman Mahajan
- Subjects
Inorganic Chemistry ,Materials science ,Chemical engineering ,Degradation (geology) ,General Materials Science ,Tio2 nanofibers ,Condensed Matter Physics ,Electrospinning - Abstract
Titanium dioxide (TiO2) nanofibers were synthesized by electrospinning to optimize the photocatalytic action efficiency. The synthesis of the fibers was carried out at four different wt% concentrations: 8, 9, 10 & 11% of polymer polyvinylpyrrolidone (PVP). The TiO2 fibers were further calcined at 700 °C to get powder form. The uncalcinated and calcined TiO2 nanofibers were characterized by using X-Ray diffraction (XRD), Raman spectroscopy, Scanning electron microscopy (SEM) and UV-Visible spectroscopy. Raman spectroscopy confirmed the rutile phase of the calcined TiO2nanofibers in powder form with a crystallite size of 34–38 nm. The surface morphology of the uncalcinated and calcined TiO2 nanofibers was examined by SEM and the fiber diameter found to be 360–540 nm. The optical bandgap of the calcined TiO2 nanofibers was found in the range of 3.29–3.24 eV. The photocatalytic activity of the TiO2 nanofibers as examined for uncalcinated and calcined nanofibers, methyl orange (MO) dye degraded up to 98 and 78%, respectively in 180 min under the exposure of UV light. Uncalcinated TiO2 nanofibers were found more suitable for degradation of MO dye as compared to calcined nanofibers.
- Published
- 2021
29. Robustness in half-metallicity, thermophysical and structural properties of Co2YAl (Y = Pd, Ag) Heuslers: a first-principles perspective
- Author
-
Ashwani Kumar, Saurabh Singh, Shakeel Ahmad Sofi, Tarun Chandel, and Naveen Thakur
- Subjects
Biophysics ,Physical and Theoretical Chemistry ,Condensed Matter Physics ,Molecular Biology - Published
- 2022
30. Global insights into the fine tuning of human A
- Author
-
Guillaume, Ferré, Kara, Anazia, Larissa O, Silva, Naveen, Thakur, Arka P, Ray, and Matthew T, Eddy
- Abstract
G protein-coupled receptor (GPCR) conformational plasticity enables formation of ternary signaling complexes with intracellular proteins in response to binding extracellular ligands. We investigate the dynamic process of GPCR complex formation in solution with the human A
- Published
- 2022
31. Effect on Compressive Strength of Concrete on Partial Replacement of Cement by Marble Dust and Fly Ash
- Author
-
Naveen Thakur, Rahul Mahla, Divyam Maharshi, and Rahul Karwasra
- Published
- 2022
32. Phytochemically and PVP stabilized TiO2 nanospheres for enhanced photocatalytic and antioxidant efficiency
- Author
-
Nikesh Thakur, Naveen Thakur, and Kuldeep Kumar
- Subjects
Mechanics of Materials ,Materials Chemistry ,General Materials Science - Published
- 2023
33. Synthesis, Characterization and Antibacterial Efficacy of Catharanthus roseus and Ocimum tenuiflorum-Mediated Silver Nanoparticles: Phytonanotechnology in Disease Management
- Author
-
Acharya Balkrishna, Naveen Thakur, Bhavana Patial, Saurabh Sharma, Ashwani Kumar, Vedpriya Arya, and Ryszard Amarowicz
- Subjects
Process Chemistry and Technology ,Chemical Engineering (miscellaneous) ,Bioengineering ,green synthesis ,silver nanoparticles ,Catharanthus roseus ,Ocimum tenuiflorum ,Antibacterial mechanism - Abstract
Nanotechnology is an emerging multidisciplinary field that has the potential to offer solutions to pharmaceutical challenges starting from drug delivery to therapeutic applications. The plant-mediated method is eco-friendly and the most inexpensive of the various techniques used to synthesize nanoparticles (NPs). In this study, silver (Ag) NPs have been successfully synthesized using leaf extract of Catharanthus roseus and Ocimum tenuiflorum. X-ray diffraction revealed an average crystalline size of 19.96 and 21.42 nm for C. roseus and O. tenuiflorum-mediated Ag NPs, respectively. Further, shape, size, and elemental composition were analyzed using a scanning electron microscope, transmission electron microscope (TEM), and energy-dispersive X-ray spectral technique. TEM study revealed spherical/spheroidal-shaped Ag NPs were formed between 10–48 nm with C. roseus and 17–55 nm with O. tenuiflorum. Both synthesized Ag NPs inhibited Escherichia coli and Bacillus subtilis, where the effect was more prominent against E. coli (MIC 3.90 ± 0 µg/mL) with O. tenuiflorum Ag NPs. Mechanistic insights of antibacterial activity were also highlighted, and the activity might be attributed to the diverse mode of action of surface functionalized phytoconstituents and NPs.
- Published
- 2023
34. Antibacterial and photocatalytic activity of undoped and (Ag, Fe) co-doped CuO nanoparticles via microwave-assisted method
- Author
-
Naveen Thakur, null Anu, Kuldeep Kumar, Vijay Kumar Thakur, Sanjeev Soni, Ashwani Kumar, and Sher Singh Samant
- Abstract
Nanoparticles (NPs) are miniature materials ranging from 1 to 100 nm. The NPs have unique chemical and physical properties due to their shape, size and high surface area. This research paper gives a detailed summary of the synthesis, characterization and applications of undoped and (Ag, Fe) co-doped CuO NPs with a diverse concentration of Fe (0.02, 0.04, 0.06 and 0.08 M) at a constant concentration of Ag (0.02 M). X-ray diffractometer (XRD) results revealed average crystallite size of NPs varies in the range 13.10-24.98 nm. Scanning electron microscopy (FE-SEM) showed that the morphology of pure synthesized CuO NPs and Energy dispersive x-ray spectroscopy (EDX) recognized the presence of Ag, Fe elements in the CuO lattice. The particle size obtained by transmission electron microscope (HR-TEM) images was found in the range 19.73-21.47 nm. Cu-O bond stretching of NPs was also confirmed by Fourier Transform Infrared (FTIR) techniques. The values of direct and indirect band gap for CuO were found to be 1.41-1.54 eV and 0.69-1.51 eV respectively. Antibacterial activity for synthesized NPs tested against gram-negative and gram-positive pathogenic bacteria. The photocatalytic properties of synthesized NPs were investigated by monitoring the methyl orange/methylene blue degradation in ultraviolet visible spectroscopy (UV-Vis).
- Published
- 2022
35. Futuristic role of nanoparticles for treatment of COVID-19
- Author
-
Naveen Thakur, Nikesh Thakur, Pankaj Chauhan, Davinder Pal Sharma, Ashwani Kumar, and Kamal Jeet
- Abstract
COVID-19 is a brand new contagious sickness caused by a brand new coronavirus referred to as intense acute breathing syndrome coronavirus 2 (SARS-CoV-2). COVID-19 is a disease that has reached each continent inside the global; it has overloaded the medical system international and it has been declared a plague by using the arena health agency. presently there are not any set up or tested treatments for COVID-19, that is permitted worldwide. Nanoparticles are described as stable colloidal particles ranging in size from 10 to 1000 nm. Nanoparticles provide many advantages to larger particles including multiplied surface-to-volume ratio and improved magnetic properties. Over the last few years, there was a regularly developing interest in the usage of nanoparticles in distinct biomedical packages inclusive of focused drug transport, hyperthermia, photoablation therapy, bioimaging and biosensors. in this review we've got hypothesize the class and synthesis of nanoparticles with diverse remedies along with photobiomodulation, drug shipping gadget, electrochemical nanotechnology biosensors, hydrothermotherapy and photocatalytic pastime which can be used for remedy and prevention of COVID-19 to lower the severity of moderate and slight instances of Coronavirus. We address current in addition to emerging therapies and prophylactic techniques that may allow us to efficaciously fight this pandemic and additionally can also assist to discover the key areas where nano-scientists can step in.
- Published
- 2022
36. Effect of (Ag, Zn) co-doping on structural, optical and bactericidal properties of CuO nanoparticles synthesized by a microwave-assisted method
- Author
-
Naveen Thakur, null Anu, Kuldeep Kumar, and Ashwani Kumar
- Subjects
Staphylococcus aureus ,Copper oxide ,Silver ,Materials science ,Band gap ,Nanoparticle ,chemistry.chemical_element ,Microbial Sensitivity Tests ,02 engineering and technology ,Zinc ,010402 general chemistry ,01 natural sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Coordination Complexes ,Spectrophotometry ,Escherichia coli ,medicine ,Fourier transform infrared spectroscopy ,Microwaves ,High-resolution transmission electron microscopy ,medicine.diagnostic_test ,technology, industry, and agriculture ,021001 nanoscience & nanotechnology ,Anti-Bacterial Agents ,0104 chemical sciences ,chemistry ,Pseudomonas aeruginosa ,Nanoparticles ,Crystallite ,0210 nano-technology ,Copper ,Bacillus subtilis ,Nuclear chemistry - Abstract
A microwave assisted synthesis method has been used for the fabrication of pure and (Ag, Zn) co-doped copper oxide (Cu1-x-yAgxZnyO) nanoparticles (NPs) with different weight ratios of zinc (0.00, 0.02, 0.04, 0.06, and 0.08 M) at a constant weight ratio of silver (0.02 M). The structure and morphology of the prepared samples were analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray diffraction (EDX), high resolution transmission electron microscopy (HR-TEM), UV-Vis spectrophotometry and Fourier transform infrared (FTIR) spectroscopy. XRD results showed that both pure and (Ag, Zn) co-doped copper oxide (CuO) NPs have a single phase monoclinic structure and no secondary phases were detected. The average crystallite size values of the NPs were found to be 13.10, 14.45, 17.59, 19.72 and 20.33 nm. FE-SEM images confirmed the changes in the morphology of pure copper oxide (CuO) NPs due to co-doping with silver and zinc metal ions. The EDX of the samples provided both semi-qualitative and semi-quantitative information. EDX confirmed the presence of Ag and Zn elements in the CuO lattice. HR-TEM images confirmed that the morphology of pure CuO was found to change from ellipsoidal to star-like structures after co-doping with Ag and Zn ions. The images also established the particle size in a range of 13.88-21.13 nm. The HR-TEM results were in agreement with the XRD results. Tauc's plots were used to determine the optical band gap of the NPs. The band gap for direct transitions was found to be 1.42-1.73 eV and that for indirect transitions was in a range of 1.28-1.78 eV. The functional group properties were also discussed using FTIR techniques. The antibacterial activity of the synthesized NPs was tested against Gram positive (Staphylococcus aureus and Bacillus subtilis) and Gram negative (Escherichia coli and Pseudomonas aeruginosa) pathogenic bacteria by an agar well diffusion method. The zones of inhibition were found to be the maximum for co-doped CuO NPs as compared to pure CuO NPs for three bacterial strains Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. It is also believed that the studied material due to its remarkable properties may be an efficient alternative in the development of smart systems for the detection of pathogens and as antimicrobial agents.
- Published
- 2021
37. Green synthesis of silver nanoparticles and evaluation of their anti-bacterial activities: use of Aloe barbadensis miller and Ocimum tenuiflorum leaf extracts
- Author
-
Saurabh Sharma, Kuldeep Kumar, and Naveen Thakur
- Subjects
silver nanoparticles ,bacillus subtilis ,green synthesis ,Science ,aloe barbadensis miller ,ocimum tenuiflorum ,anti-bacterial agent - Abstract
The presence of various phytochemicals makes the leaf extract-based green synthesis advantageous to other conventional methods, as it facilitates the production of non-toxic by-product. In the present study, leaf extracts from two different plants: Aloe barbadensis miller and Ocimum tenuiflorum, were used to synthesise Ag nanoparticles. The absorbance at 419-432 nm from UV-visible spectroscopy indicates the formation of Ag in the synthesised samples. The effect of precursors’ concentration on the stability, size and shape of the synthesised samples has also been investigated at constant heating temperature, stirring time, and the pH of the solution. The TEM results showed that all the synthesised samples of nanoparticles demonstrated stability with a size range of 7-70 and 9-48 nm with Aloe barbadensis miller and Ocimum tenuiflorum leaf extracts, respectively. The formation of smaller Ag nanoparticles due to utilisation of different precursor concentration and leaf extracts was also explained. The synthesised samples’ anti-bacterial activity was examined against the pathogens, Bacillus subtilis, Staphylococcus aureus, and Escherichia coli. In general, the green synthesis approach established a prospective for developing highly stable Ag nanoparticles with rigid particle shape/size distribution from different leaf extracts for the development of better anti-bacterial agents.
- Published
- 2021
38. Silver Triflate Catalyzed Domino Reactions of o ‐Alkynylanilines: An Approach Toward Unsymmetrical Diarylacetates and Triarylmethanes
- Author
-
Santosh D. Jadhav, Tavinder Singh, Naveen Thakur, and Anand Singh
- Subjects
Organic Chemistry - Published
- 2022
39. Ocimum tenuiflorum leaf extract as a green mediator for the synthesis of ZnO nanocapsules inactivating bacterial pathogens
- Author
-
Kuldeep Kumar, Naveen Thakur, Mohinder Singh Chauhan, and Saurabh Sharma
- Subjects
biology ,Scanning electron microscope ,General Chemical Engineering ,02 engineering and technology ,General Chemistry ,Bacillus subtilis ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Ocimum ,biology.organism_classification ,01 natural sciences ,Biochemistry ,Industrial and Manufacturing Engineering ,Nanocapsules ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Transmission electron microscopy ,Materials Chemistry ,Photocatalysis ,Methyl orange ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Nuclear chemistry - Abstract
ZnO nanoparticles, as fabricated using Ocimum tenuiflorum leaf extract, have been investigated for their photocatalytic and antimicrobial activities. However, the ZnO nanoparticles were synthesized using precursor, Zn(CH3COO)2·2H2O at different concentrations (5, 10 and 50 mmol kg−1) at 70 °C and pH 11.5. The synthesized materials were characterized by employing Fourier transform infrared spectroscopy, UV–Visible, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy techniques. As recorded from UV–Visible studies, there was a drastic decrease in the energy band gap value (Eg) from 3.63 to 3.20 eV with the concentration of precursor, Zn(CH3COO)2·2H2O. The synthesized materials were examined for their photocatalytic activity towards the degradation of methyl orange dye and also for antibacterial action against Bacillus subtilis, Staphylococcus aureus and Escherichia coli pathogenic bacteria.
- Published
- 2020
40. Truncated Hemoglobin O Carries an Autokinase Activity and Facilitates Adaptation of Mycobacterium tuberculosis Under Hypoxia
- Author
-
Sandeep Singh, Deepti Sethi, Kanak L. Dikshit, Naveen Thakur, Ajay Chhaya, Himani Datta, and Mangesh Dattu Hade
- Subjects
0301 basic medicine ,Mycobacterium bovis ,030102 biochemistry & molecular biology ,biology ,Physiology ,Chemistry ,Clinical Biochemistry ,Mutant ,Autophosphorylation ,Cell Biology ,biology.organism_classification ,Biochemistry ,Cell biology ,Mycobacterium tuberculosis ,Cell membrane ,Complementation ,03 medical and health sciences ,030104 developmental biology ,medicine.anatomical_structure ,medicine ,General Earth and Planetary Sciences ,Respiratory system ,Molecular Biology ,Gene ,General Environmental Science - Abstract
Aims: Although the human pathogen, Mycobacterium tuberculosis (Mtb), is strictly aerobic and requires efficient supply of oxygen, it can survive long stretches of severe hypoxia. The mechanism responsible for this metabolic flexibility is unknown. We have investigated a novel mechanism by which hemoglobin O (HbO), operates and supports its host under oxygen stress. Results: We discovered that the HbO exists in a phospho-bound state in Mtb and remains associated with the cell membrane under hypoxia. Deoxy-HbO carries an autokinase activity that disrupts its dimeric assembly into monomer and facilitates its association with the cell membrane, supporting survival and adaptation of Mtb under low oxygen conditions. Consistent with these observations, deletion of the glbO gene in Mycobacterium bovis bacillus Calmette-Guerin, which is identical to the glbO gene of Mtb, attenuated its survival under hypoxia and complementation of the glbO gene of Mtb rescued this inhibition, but phosphorylation-deficient mutant did not. These results demonstrated that autokinase activity of the HbO modulates its physiological function and plays a vital role in supporting the survival of its host under hypoxia. Innovation and Conclusion: Our study demonstrates that the redox-dependent autokinase activity regulates oligomeric state and membrane association of HbO that generates a reservoir of oxygen in the proximity of respiratory membranes to sustain viability of Mtb under hypoxia. These results thus provide a novel insight into the physiological function of the HbO and demonstrate its pivotal role in supporting the survival and adaptation of Mtb under hypoxia.
- Published
- 2020
41. Use of Photocatalyst in Self-Cleaning Constructions Material: A Review
- Author
-
Naveen Thakur, S. B. Singh, and null Anshuman
- Published
- 2022
42. First-principles calculations to investigate structural stability, half-metallic behavior, thermophysical and thermoelectric properties of Co2YAl (Y = Mo, Tc) full Heusler compounds
- Author
-
Ashwani Kumar, Shakeel Ahmad Sofi, Tarun Chandel, and Naveen Thakur
- Subjects
Physical and Theoretical Chemistry ,Condensed Matter Physics ,Biochemistry - Published
- 2023
43. Slow Conformational Dynamics of the Human A(2A) Adenosine Receptor are Temporally Ordered
- Author
-
Shushu Wei, Naveen Thakur, Arka P. Ray, Beining Jin, Samuel Obeng, Christopher R. McCurdy, Lance R. McMahon, Hugo Gutiérrez-de-Terán, Matthew T. Eddy, and Rajan Lamichhane
- Subjects
Receptor, Adenosine A2A ,Structural Biology ,Molecular Conformation ,Humans ,Molecular Dynamics Simulation ,Molecular Biology ,Article - Abstract
A more complete depiction of protein energy landscapes includes the identification of different function-related conformational states and the determination of the pathways connecting them. We used total internal reflection fluorescence (TIRF) imaging to investigate the conformational dynamics of the human A(2A) adenosine receptor (A(2A)AR), a class A GPCR, at the single-molecule level. Slow, reversible conformational exchange was observed among three different fluorescence emission states populated for agonist-bound A(2A)AR. Transitions among these states predominantly occurred in a specific order, and exchange between inactive and active-like conformations proceeded through an intermediate state. Models derived from molecular dynamics simulations with available A(2A)AR structures rationalized the relative fluorescence emission intensities for the highest and lowest emission states but not the transition state. This suggests that the functionally-critical intermediate state required to achieve activation is not currently visualized among available A(2A)AR structures.
- Published
- 2021
44. New Insights Into the Function of Flavohemoglobin in
- Author
-
Naveen, Thakur, Amar Nath, Sharma, Mangesh Dattu, Hade, Ajay, Chhaya, Ashwani, Kumar, Ravinder Singh, Jolly, and Kanak L, Dikshit
- Subjects
Disulfides ,Lactic Acid ,Mycobacterium tuberculosis ,Oxidoreductases ,Oxidation-Reduction ,NADP - Published
- 2021
45. Nanotechnology Interventions in the Management of COVID-19: Prevention, Diagnosis and Virus-Like Particle Vaccines
- Author
-
Nikesh Thakur, Vedpriya Arya, Acharya Balkrishna, Eugenie Nepovimova, Akansha Rohela, Rachna Verma, Pankaj Kumar, Naveen Thakur, Dinesh Kumar, Kamil Kuca, and Ashwani Kumar
- Subjects
Pharmacology ,Coronavirus disease 2019 (COVID-19) ,business.industry ,SARS-CoV-2 ,diagnosis ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Immunology ,Psychological intervention ,COVID-19 ,Nanotechnology ,Context (language use) ,Review ,Vaccine delivery ,virus-like particle vaccines ,Virus-Like Particle Vaccines ,Infectious Diseases ,prevention ,Drug Discovery ,Pandemic ,Medicine ,Pharmacology (medical) ,business ,Personal protective equipment - Abstract
SARS-CoV-2 claimed numerous lives and put nations on high alert. The lack of antiviral medications and the small number of approved vaccines, as well as the recurrence of adverse effects, necessitates the development of novel treatment ways to combat COVID-19. In this context, using databases such as PubMed, Google Scholar, and Science Direct, we gathered information about nanotechnology’s involvement in the prevention, diagnosis and virus-like particle vaccine development. This review revealed that various nanomaterials like gold, polymeric, graphene and poly amino ester with carboxyl group coated magnetic nanoparticles have been explored for the fast detection of SARS-CoV-2. Personal protective equipment fabricated with nanoparticles, such as gloves, masks, clothes, surfactants, and Ag, TiO2 based disinfectants played an essential role in halting COVID-19 transmission. Nanoparticles are used not only in vaccine delivery, such as lipid nanoparticles mediated transport of mRNA-based Pfizer and Moderna vaccines, but also in the development of vaccine as the virus-like particles elicit an immune response. There are now 18 virus-like particle vaccines in pre-clinical development, with one of them, developed by Novavax, reported being in phase 3 trials. Due to the probability of upcoming COVID-19 waves, and the rise of new diseases, the future relevance of virus-like particles is imperative. Furthermore, psychosocial variables linked to vaccine reluctance constitute a critical problem that must be addressed immediately to avert pandemic.
- Published
- 2021
46. Structural Insights into Activation of a Human G Protein‐Coupled Receptor by Membrane Phospholipids
- Author
-
Arka Prabha Ray, Naveen Thakur, Beining Jin, Matthew T. Eddy, and Alexander Duong
- Subjects
Membrane ,Chemistry ,Genetics ,Biophysics ,Molecular Biology ,Biochemistry ,Biotechnology ,G protein-coupled receptor - Published
- 2021
47. A Comparative Analysis of Breast Density between Normal and Carcinoma Breast Cases
- Author
-
Naveen Thakur
- Subjects
Oncology ,medicine.medical_specialty ,business.industry ,Internal medicine ,Medicine ,Breast density ,business ,Breast carcinoma - Published
- 2021
48. Nanotechnology : Agriculture, Environment and Health
- Author
-
Acharya Balkrishna, Naveen Thakur, Vedpriya Arya, Ashwani Kumar, Acharya Balkrishna, Naveen Thakur, Vedpriya Arya, and Ashwani Kumar
- Subjects
- Nanoscience, Nanochemistry, Biotechnology, Public health, Agricultural biotechnology, Pollution
- Abstract
This book presents an update on the state of the art in nanobiology and various nanoparticle synthesis and characterization methods. Further, the application of nanomaterials in agriculture (nanobiofertilizers and nanobiopesticides), environmental remediation (bio-nanoaugmentation), and public health (diagnosis, treatment, and drug delivery) is also a key area of this book. This book serves as a roadmap for researchers to fill various gaps by designing and organizing future research. It offers a crucial reference for academic researchers in nanotechnology, medicine, material science, toxicology, agriculture, environmental science, and biomedical science.
- Published
- 2024
49. Effect of natural radionuclide's in the environment along the Jwalamukhi thrust of Himachal Pradesh, North West Himalayas, India
- Author
-
Naveen, Thakur, Reetika, Bhadwal, Jitender, Kumar, Manpreet, Kaur, Rohit, Mehra, and Ajay, Kumar
- Subjects
Radioisotopes ,Soil ,Radiation Monitoring ,Radon ,Potassium Radioisotopes ,Humans ,India ,Soil Pollutants, Radioactive ,Radium - Abstract
This research paper is devoted to measure the activity contents of natural radionuclide, like, radium (
- Published
- 2020
50. Single-molecule view of slow and sequential conformational transitions of A2A adenosine receptor
- Author
-
Shushu Wei, Naveen Thakur, Arka Prabha Ray, Beining Jin, Samuel Obeng, Christopher R. McCurdy, Lance R. McMahon, Hugo Gutiérrez-de-Terán, Matthew T. Eddy, and Rajan Lamichhane
- Subjects
Biophysics - Published
- 2022
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