Browsing by Author "Komal Kumari"

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Bioactives Promiscuity of Mucin: Insight from Multi-Spectroscopic, Thermodynamic, and Molecular Dynamic Simulation Analyses
(American Chemical Society, 2023) Komal Kumari; Avinash Kumar; Ahamad Tamanna Manjur; Surajit Rakshit
Mucosal drug delivery plays an increasing role in the clinical setting owing to mucin’s advantageous biochemical and pharmacological properties. However, how this transport system recognizes different substrates remains unclear. In this study, we explore the mechanism of bioactive (quercetin and berberine) promiscuity of mucin using various spectroscopic techniques and molecular dynamics simulations. The UV-visible spectroscopy results and the decreased fluorescence intensity of mucin in the presence of the bioactive compounds via a static quenching mechanism confirmed ground-state complex formation between the bioactives and mucin. The binding constants (Kb) were evaluated at different temperatures to afford Kb values of ∼104 Lmol-1, demonstrating the moderate and reasonable affinity of the bioactives for mucin, yielding greater diffusion into the tissues. Thermodynamic analysis and molecular dynamics (MD) simulations demonstrate that mucin-bioactive complex formation occurs primarily because of electrostatic/ionic interactions, while hydrophobic interactions were also crucial in stabilizing the complex. Far-UV circular dichroism spectroscopy showed that bioactive binding induced secondary structural changes in mucin. Sitemap and MD simulation indicated the principal binding site of mucin for the bioactives. This study also provides insight into the bioactives promiscuity of mucin in the presence of a crowded environment, which is relevant to the biological activity of mucin in vivo. An in vitro drug release study revealed that crowding assisted drug release in an enhanced burst manner compared with that in a dilute buffer system. This work thus provides fresh insight into drug absorption and distribution in the native cellular environment and helps direct new drug design and use in pharmaceutical and pharmacological fields. © 2023 American Chemical Society
Crowder Chain Length Variability and Excluded Volume Effect on the Phase Separation Behavior of Mucin
(American Chemical Society, 2024) Komal Kumari; Anant Kumar Singh; Priyankar Mandal; Surajit Rakshit
Phase separation within cellular membranes, a critical process underpinning diverse cellular functions, is significantly influenced by transmembrane proteins. Therefore, elucidating the behavior of a transmembrane protein in its phase-separated state is of utmost importance. Our study explores mucin behavior in the cellular milieu, aiming to determine the role of crowder chain length and excluded volume in phase separation. Confocal microscopy images demonstrate the strong partitioning of mucin into the condensed phase influenced by hydrophobic and electrostatic interactions. Fluorescence recovery after photobleaching analysis revealed increased mobility in the presence of shorter chain length crowders, indicating the dynamic behavior of protein within condensed phases. Excluded volume calculation using the theoretical model emphasizes its importance in mucin phase separation under crowded conditions. Our findings underscore the ability of mucin to phase-separate under crowded conditions, highlighting the crucial role of excluded volume and enhancing our understanding of its involvement in cancer progression. © 2024 American Chemical Society.
Efficient Photocatalytic Hydrogen Production Using In-Situ Polymerized Gold Nanocluster Assemblies
(John Wiley and Sons Inc, 2025) Debkumar Bera; Sukhendu Mahata; Maitrayee Biswas; Komal Kumari; Surajit Rakshit; N. Nonappa; Srabanti Ghosh; Nirmal Goswami
Gold nanoparticles (NPs) are widely recognized as co-catalysts in semiconductor photocatalysis for enhancing hydrogen production efficiency, but they are often overlooked as primary catalysts due to the rapid recombination of excited-state electrons. This study presents an innovative gold-based photocatalyst design utilizing an in situ dopamine polymerization-guided assembly approach for efficient H2 generation via water splitting. By employing gold superclusters (AuSCs; ≈100 nm) instead of ultra-small gold nanoclusters (AuNCs; ≈2 nm) before polymerization, unique nanodisk-like 3D superstructures consisting of agglomerated 2D polydopamine (PDA) nanosheets with a high percentage of uniformly embedded AuNCs are created that exhibit enhanced metallic character post-polymerization. The thin PDA layer between adjacent AuNCs functions as an efficient electron transport medium, directing excited-state electrons toward the surface and minimizing recombination. Notably, the AuSCs@PDA structure shows the largest potential difference (26.0 mV) compared to AuSCs (≈18.4 mV) and PDA NPs (≈14.6 mV), indicating a higher population of accumulated photo-generated carriers. As a result, AuSCs@PDA achieves a higher photocurrent density, improved photostability, and lower charge transfer resistance than PDA NPs, AuSCs, or AuNCs@PDA, with the highest hydrogen evolution rate of 3.20 mmol g−1 h−1. This work highlights a promising in situ polymerization strategy for enhancing photocatalytic hydrogen generation with metal nanoclusters. © 2024 Wiley-VCH GmbH.
Neoantigen Identification and Dendritic Cell-Based Vaccines for Lung Cancer Immunotherapy
(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Komal Kumari; Amarnath Singh; Archana Chaudhary; Rakesh Kumar Singh; Asheesh Shanker; Vinay Kumar; Rizwanul Haque
Immunotherapies can treat many cancers, including difficult-to-treat cases such as lung cancer. Due to its tolerability, long-lasting therapeutic responses, and efficacy in a wide spectrum of patients, immunotherapy can also help to treat lung cancer, which has few treatment choices. Tumor-specific antigens (TSAs) for cancer vaccinations and T-cell therapies are difficult to discover. Neoantigens (NeoAgs) from genetic mutations, irregular RNA splicing, protein changes, or viral genetic sequences in tumor cells provide a solution. NeoAgs, unlike TSAs, are non-self and can cause an immunological response. Next-generation sequencing (NGS) and bioinformatics can swiftly detect and forecast tumor-specific NeoAgs. Highly immunogenic NeoAgs provide personalized or generalized cancer immunotherapies. Dendritic cells (DCs), which originate and regulate T-cell responses, are widely studied potential immunotherapeutic therapies for lung cancer and other cancers. DC vaccines are stable, reliable, and safe in clinical trials. The purpose of this article is to evaluate the current status, limitations, and prospective clinical applications of DC vaccines, as well as the identification and selection of major histocompatibility complex (MHC) class I and II genes for NeoAgs. Our goal is to explain DC biology and activate DC manipulation to help researchers create extremely potent cancer vaccines for patients. © 2024 by the authors.
Role of TREM2 in Alzheimer's disease and its consequences on β-amyloid, tau and neurofibrillary tangles
(Bentham Science Publishers, 2019) Anurag K. Singh; Gaurav Mishra; Anand Maurya; Rajendra Awasthi; Komal Kumari; Abhimanyu Thakur; Arati Rai; Gopal Kumar Rai; Bhupesh Sharma; Giriraj T. Kulkarni; Santosh Kumar Singh
Alzheimer's Disease (AD) is age-related neurodegenerative disorder recognized by a steadily gradual cognitive decline that has devastating personal and socioeconomic implications. Recently, some genetic factors for AD have been identified which attracted wide attention of researchers in different areas of AD biology and possible new therapeutic targets. Alternative forms of triggering receptor expressed on myeloid cells 2 (TREM2) genes are examples of such risk factors, which contribute higher risk for developing AD. Comprehending TREM2 function pledge to provide salient insight into how neuroinflammation contributes to AD pathology. The dearth of microglial TREM2 shepherd to augmented tau pathology is couple with frequent enhancement of activated neuronal stress kinases. The involvement of TREM2 in the regulation of tau-associated innate immune response of the CNS has clearly demonstrated through these findings. However, whether decrease level of TREM2 assists pathology of tau through changed clearance and pathological escalation of tau or through direct contact between microglia and neuron and any alternative possible mechanisms need to examine. This review briefly summarizes distinct functional roles of TREM2 in AD pathology and highlights the TREM2 gene regulation. We have also addressed the impact of TREM2 on β-amyloid plaques and tau pathology in Alzheimer’s disease. © 2019 Bentham Science Publishers.
Species distribution models: concepts, tools, and applications
(Elsevier, 2025) Komal Kumari; Prashant Kumar Srivastava
The distribution mapping of vegetation diversity is crucial accurate monitoring and management of valuable and key stone species. SDM is needed in ecological restoration, understanding distribution invasive species and their risks, forest and natural resource management, etc. With the advancement in remote sensing and geographic information system techniques, several modeling techniques are now existing in technical literature domain to determine the spatial distributional pattern of any species. This chapter deals with overview of the numerous species distribution modeling techniques through the important environmental variables such as climates, elevation, temperature, terrain, etc. This chapter provides a detailed account of ecological niche models, correlative models, and spatial models to understand the architecture of the models and applications. © 2026 Elsevier Inc. All rights reserved..
Strategic use of nanotechnology in drug targeting and its consequences on human health: A focused review
(Akademiai Kiado Rt., 2019) Anand Maurya; Anurag Kumar Singh; Gaurav Mishra; Komal Kumari; Arati Rai; Bhupesh Sharma; Giriraj T. Kulkarni; Rajendra Awasthi
Since the development of first lipid-based nanocarrier system, about 15% of the present pharmaceutical market uses nanomedicines to achieve medical benefits. Nanotechnology is an advanced area to meliorate the delivery of compounds for improved medical diagnosis and curing disease. Nanomedicines are gaining significant interest due to the ultra small size and large surface area to mass ratio. In this review, we discuss the potential of nanotechnology in delivering of active moieties for the disease therapy including their toxicity evidences. This communication will help the formulation scientists in understanding and exploring the new aspects of nanotechnology in the field of nanomedicine. © 2019 The Author(s)
Tailoring the photoluminescence of AIE-type gold nanoclusters via biomineralization-inspired polymorphism
(Royal Society of Chemistry, 2024) Sukhendu Mahata; Satya Ranjan Sahoo; Arun Mukhopadhyay; Komal Kumari; Surajit Rakshit; Nirmal Goswami
Tailoring the aggregation-induced emission (AIE) characteristics of well-defined metal nanoclusters (MNCs) is highly sought after for numerous practical applications. Studies have primarily focused on assembling AIE-type MNCs using monomorphic molecules. Achieving polymorphic assemblies, with different molecular arrangements could provide valuable insights into the role of external molecular matrices on the photoluminescence (PL) behaviour of these NCs. In this study, by mimicking biomineralization, we successfully embedded AIE-type Au22SG18 NCs within different polymorphic environments of CaCO3. Upon incorporation into CaCO3 matrices such as, calcite, vaterite and a mixture of both, the PL was enhanced in all the inorganic composites accompanied by a significant blue shift. In the metastable vaterite matrix, Au22SG18 NCs exhibited the highest blue shift in the PL spectrum while in the stable crystalline matrix of calcite, the NCs showed the highest PL intensity as well as excited state lifetime. Time-resolved spectroscopic and single-molecule Raman studies revealed that variations in the PL of NCs are linked to the stability of their polymorphic structures, progressing from vaterite to a vaterite/calcite mixture, and finally to calcite. These findings shed light on the crucial role of external molecular arrangement in the AIE behaviour of MNCs. © 2025 The Royal Society of Chemistry.
Unravelling structural insights into ligand-induced photoluminescence mechanisms of sulfur dots
(Royal Society of Chemistry, 2024) Satya Ranjan Sahoo; Arun Mukhopadhyay; Sukhendu Mahata; Komal Kumari; N.V.S. Praneeth; Ananya Baksi; Saumyakanti Khatua; Sumit Saha; Surajit Rakshit; Nirmal Goswami
Sulfur dots (S-QDs) hold promise as a new category of metal-free, luminescent nanomaterials, yet their practical application faces challenges primarily due to a limited understanding of their structure and its impact on their optical properties. Herein, by employing a spectrum of aliphatic and aromatic ligands, we identify the surface structure and composition of S-QDs while delineating the pivotal role of ligands in inducing photoluminescence. Thiol-functionalized ligands, such as 4-mercapto benzoic acid and glutathione, notably promote the formation of both green and blue luminescent S-QDs, boosting a high quantum yield of up to 56%. Further investigation on the synthesis of S-QDs with 4-mercapto benzoic acid unveils the dual role of H2O2: etching sulfur powder and oxidizing the -SH group to -SO2H. These oxidized ligands passivate the S-QD surface through hydrogen bonding. Electrospray ionization mass spectrometry analysis unveils the presence of distinct sulfur species such as [S4(C6H5SO2H)4(H2O)2H]+ and [S6(C6H5SO2H)6(H2O)3H]+, while XPS analysis confirms the existence of zerovalent sulfur and oxidized sulfur species including SO32− and SO42−. Further detailed spectroscopic examination demonstrates that S-QDs predominantly exist as aggregated entities, with the emission wavelength correlating with the degree of aggregation. The absence of photoluminescence in aggregations devoid of ligands underscores the critical role of ligands in the photoluminescence genesis of S-QDs. © 2024 The Royal Society of Chemistry.