Browsing by Author "Vivek Mishra"

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Comparative study of thermal degradation behavior of graft copolymers of polysaccharides and vinyl monomers
(2012) Arti Srivastava; Vivek Mishra; Pooja Singh; Ambika Srivastava; Rajesh Kumar
The thermal degradation of graft copolymers of both polysaccharides (guar gum and xanthan gum) showed gradual decrease in mass loss. Pure guar gum degraded about 95% but pure xanthan gum degraded about 76% up to 1173.15 K, while graft copolymers of guar gum and xanthan gum degraded only 65-76% up to 1173.15 K. Acrylic acid grafted guar gum and xanthan gum showing two-step degradation with formation of anhydride and ketonic linkage during heating, same pattern of degradation was found for xanthan gum-g-methacrylic acid. Guar gum-g-acrylamide degraded in single step and xanthan gum-g-acrylamide started to degrade above 448.15 K and it is a two-stage process and imparts thermal stability due to the formation of imide linkage with evolution NH 3. Guar gum-g-methacrylamide degraded in three steps due to the loss of NH 3 and CO 2 successively. 4-vinyl pyridine grafted both polysaccharides show single step degradation due to loss of pyridine pendent. N-vinyl formamide grafted guar gum and xanthan gum started to degrade at about 427.15 K, showed two-stage degradation process with the evolution of CO and NH 3 molecules while guar gum-g-(N-vinyl-2-pyrrolidone) degraded into two steps by the loss of pyrrolidone nucleus. Gum-g-2-acrylamido-2-methyl-1- propane sulfonic acid (AMPS) showed two-step degradation processes in two successive degradation steps, while xanthan gum-g-AMPS has started degradation at about 427.15 K and completed in five degradation steps. Overall, it was found that the grafted polysaccharides are thermally more stable than pure polysaccharides. © 2011 Akadémiai Kiadó, Budapest, Hungary.
Coumarin-based polymer and its silver nanocomposite as advanced antibacterial agents: Synthetic path, kinetics of polymerization, and applications
(2012) Ambika Srivastava; Vivek Mishra; Pooja Singh; Rajesh Kumar
A novel polymer bearing coumarin pendants of 4-allyloxy-2H-chromen-2-one (ACO) was synthesized by atom transfer radical polymerization (ATRP) in toluene at 110°C using 2-Bromoisobutyryl bromide (BIBB), Cu (I) Br, and 2,2'-bipyridyl (bpy) as initiator, catalyst, and ligand, respectively. The most appropriate molar concentration ratio of [ACO]: [BIBB]: [Cu (I) Br]: [bpy] was found to be 40: 1: 1: 2 for controlled polymerization. Successful chain extension polymerization of poly (4-allyloxy-2H-chromen-2-one) (PACO) confirms the livingness of the process. The activation energy (E a) (76.26 kJ mol -1) and enthalpy of activation (ΔH) (73.07 kJ mol -1) were in good agreement to each other proving the feasibility of the reaction and negative value of entropy of activation (ΔS) (-320 J mol -1 K -1) supported the highly restricted movement of reacting species in transition state during polymerization. Initial polymer decomposition temperature of PACO was found to be 130°C. SEM analysis revealed that polymer surface is not smooth with pointed rod like shapes. The polymer/Ag nanocomposite was synthesized and examined in view of antibacterial effect against Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Proteus mirabilis, and Klebsiella pneumonae. PACO and its Ag nanocomposite (PACON) have been found to be active selectively against bacterial pathogen E. fecalis with minimum inhibitory concentration of 50 and 32 μg mL -1, respectively. Copyright © 2012 Wiley Periodicals, Inc.
Cyclic Polymer of N-Vinylpyrrolidone via ATRP Protocol: Kinetic Study and Concentration Effect of Polymer on Click Chemistry in Solution
(Pleiades Publishing, 2019) Vivek Mishra; Rajesh Kumar
Abstract: We hereby report the synthesis of a well-defined cyclic poly(N-vinylpyrrolidone) using propargyl-2-bromoisobutyrate as an ATRP initiator and NaN3 followed by the click reaction of alkynyl and azide groups. The decrease of polymer concentration is favorable for cyclization reaction, while the increase of polymer concentration leads to condensation reaction. © 2019, Pleiades Publishing, Ltd.
Development of ionic liquid-capped carbon dots derived from Tecoma stans (L.) Juss. ex Kunth: Combatting bacterial pathogens in diabetic foot ulcer pus swabs, targeting both standard and multi-drug resistant strains
(Elsevier B.V., 2023) Nisha Yadav; Deeksha Mudgal; Shivakant Mishra; Hitesh Sehrawat; Niraj Kumar Singh; Kalicharan Sharma; Prabodh Chander Sharma; Jay Singh; Vivek Mishra
Bacterial infection is rapidly growing and is a severe danger to global welfare worldwide. Consequently, there is a growing demand for novel antibacterial medications. As an outcome, the evaluation of antibacterial assets of carbon dots (CDs) including a variety of ionic liquids (ILs) were employed to reside advance notice of the structure tunability of ILs along with abundant surface functional group of designed amine-modified CDs, have recently sparked a lot of interest. In this study for the first time, highly efficient ionic-liquid decorated CDs were synthesized to assess the impact of capped-ionic liquid on the degree of antibacterial activity. Fluorescent amine-modified CDs (CDs-NH2) were obtained from the Tecoma stans (yellow elder flower) extract by a single-step carbonization method in presence of ethylenediamine, and then capped with ionic liquids; 3-(carboxymethyl)-1-methyl-1-H-imidazol-3-ium bromide (ILIM) and 3-(carboxymethyl)-1-methyl-1-H-benzo[d]imidazole-3-ium bromide (ILBIM) by a simple carbodiimide chemistry. In-vitro antibacterial activity of CDs-NH2, ILIM@CDs and ILBIM@CDs were evaluated against common pathogens, Escherichia coli (E. coli) as Gram(-ive) bacteria and Staphylococcus aureus (S. aureus) as Gram(+ive) bacteria as well as against clinical multi-drug resistant strain obtained from pus swab of diabetic foot ulcer, by microdilution method as well as well-diffusion method. The results showed that functional ILs-capped CDs have enhanced antibacterial activity against standard (E. coli, S. aureus) and clinical resistant bacterial strains, with minimal inhibitory concentrations (MICs) values range from 0 to 64 μg/mL for standard E. coli/ S. aureus and 250 μg/mL for drug resistant clinical strains, respectively. Structure activity analysis and molecular docking studies revealed that the antibacterial activity of ILBIM@CDs/ILIM@CDs is particularly better compared to CDs-NH2 and ionic-liquids. © 2023 SAAB
Effect of energy variation on the dissipative evolution of the system in heavy-ion fusion reactions
(American Physical Society, 2018) N.K. Rai; Vivek Mishra; Ajay Kumar
In heavy-ion fusion reactions, the energy of the projectile couples with the intrinsic degrees of freedom of the target during the collision process and this leads to a dissipative phenomenon. Consequently, the dissipation in the system causes the angular momentum hindrance during the fusion process. In this work, we have focused on the dissipative behavior of the fusing nuclei and its dependency on the incident energy. The dissipative evolution of the system depends not only on the entrance channel mass asymmetry but also on the incident energy, which was not mentioned in earlier studies. Moreover, the dissipative behavior of the fusing nuclei is also compared with respect to the entrance channel parameters like mass asymmetry α and the Coulomb interaction term ZPZT. The dissipation phenomenon decreases when the mass asymmetry increases and it increases when the Coulomb interaction term ZPZT increases. © 2018 American Physical Society.
Effects of G-CSF on serum cholesterol and development of atherosclerotic plaque in apolipoprotein E-deficient mice
(E-Century Publishing Corporation, 2014) Satyesh K. Sinha; Vivek Mishra; Santosh Nagwani; Tripathi B. Rajavashisth
Macrophage colony stimulating factor (M-CSF) is known to have profound effects upon vascular pathologies, but potential roles of other colony stimulating factors (CSF) are not well understood. We treated apo E deficient (apo E-/-) mice with granulocyte colony stimulating factor (G-CSF) or vehicle daily for 9 weeks, during which time they were fed a Western-style diet. G-CSF treatment resulted in increased proportions of circulating monocytes (6.9 ± 2.2% vs. 3.8 ± 0.3%; p < 0.05), a trend towards increased neutrophils (33.5 ± 19.1% vs. 22.2 ± 7.8%; p = 0.17), and decreased serum levels of total cholesterol (981 ± 594 vs. 1495 ± 1009 mg/dL; p < 0.005) compared to control mice. There was a trend towards less low density lipoprotein (LDL) in G-CSF treated mice (24.6 ± 2.4% vs. 37.4 ± 12.3%; p = 0.10). A greater proportion of bone marrow cells from G-CSF treated mice expressed membrane type 1 matrix metalloprotease (MT1-MMP) (G-CSF: 14.5 ± 5.5%; Control: 6.2 ± 5.0%; p < 0.05) compared to bone marrow cells from vehicle treated mice. G-CSF treatment was also associated with smaller atheromatous plaque, decreased Oil red O staining, and decreased infiltration of both Monocyte/Macrophage Marker Antibody (MOMA-2) and F4/80 dependent macrophage populations into aortic lesions. However, decreased plaque area appeared to be largely due to lower cholesterol levels in G-CSF-treated mice. Lesions in G-CSF treated mice appeared to be structurally distinct from control mice, containing relatively less lipid and macrophages. Our results suggest important roles for G-CSF in cholesterol metabolism, mobilization of bone marrow stem cells that might alter plaque development, and accumulation of lipids and macrophages into atherosclerotic lesions. © 2014, E-Century Publishing Corporation. All rights reserved.
Functional Fluorescent Materials: Applications in Sensing, Bioimaging, and Optoelectronics
(CRC Press, 2024) Vivek Mishra; Syed Sibtay Razi; Ajit Kumar
Functional Fluorescent Materials: Applications in Sensing, Bioimaging, and Optoelectronics explains functional molecular probes (organic/inorganic materials, polymers, nanomaterials), with a focus on those that represent spectroscopic properties with detection of different analytes and specific roles in molecular recognition and their applications. It broadly covers molecular recognition to applications of fluorescence reporters, starting from optoelectronic properties of materials, detection of heavy metals, through biological macromolecules, and further to a living cell, tissue imaging, and theranostics. Features: • Covers different aspects of fluorescence spectroscopy ranging from chemical, physical, and biological aspects along with optoelectronic properties, mechanisms, and applications. • Describes all types of chemical and functionalized fluorescent nanomaterials. • Provides additional information on different kinds of fluorescence reporters. • Explains the concept of fluorescence spectroscopy and its role in human health care. • Discusses changes in static and dynamic properties of fluorescent probes and molecular recognitions. This book is aimed at graduate students and researchers in materials, chemical engineering, and engineering physics. © 2024 selection and editorial matter, Vivek Mishra, Syed Sibtay Razi, and Ajit Kumar; individual chapters, the contributors.
Graft copolymerization of carboxymethylcellulose: An overview
(2012) Vivek Mishra; Rajesh Kumar
The modification of Carboxymethylcellulose (CMC) through vinyl monomers containing different functional groups to increase its functionality has attracted the attention of researchers. Among the various methods for modifying polymers, graft copolymerization appears to be highly attractive and has made a paramount contribution towards improved industrial and biomedical applications. In recent years, the polymer functionalization of CMC has greatly benefited from advances in polymerization techniques. Graft copolymerization technique provides different functionalities onto CMC surface, where CMC and its modified graft copolymers have multifunctional characteristics and known for their potentially wider range of applications. In addition to the conventional grafting techniques, we highlight the recent developments in graft copolymerization process that allows increase control over the grafting and permits the production of functional cellulose which possess improved physical and chemical properties.
Grafting of 4-aminoantipyrine from guar gum substrates using graft atom transfer radical polymerization (ATRP) process
(2011) Vivek Mishra; Rajesh Kumar
ATRP graft copolymerization of 4-aminoantipyrine (AAP) was carried out successfully at 50 °C from a guar gum based macroinitiator (GGBr), Cu(I)Br and 2,2′-bipyridyl(bpy) as initiator, catalyst and ligand, respectively, in water. Factors affecting the conversion and rate of graft copolymerization such as temperature, concentration of monomer, catalyst, ligand and initiator were studied. The best initial molar concentration ratio of [AAP]:[GGBr]:[Cu(I) Br]:[bpy] was found 100:1:1:2 for controlled graft copolymerization. The plot ln[M]0/[M]t vs. time showed first order kinetics with respect to 4-aminoantipyrine. The activation energy (Ea = 25.15 kJ mol-1), enthalpy of activation (ΔH‡ = 22.42 kJ mol-1) and negative value of entropy of transition state (ΔS‡ = -233.82 J mol-1 K-1) support the progress of polymerization reaction. The % grafting ratio was found to be 5184% and the graft copolymer was characterised by 1H NMR, FTIR, UV, GPC, XRD, TGA and DSC analyses. © 2011 Elsevier Ltd All rights reserved.
Multinucleated giant cells in atherosclerotic plaques of human carotid arteries: Identification of osteoclast-like cells and their specific proteins in artery wall
(Academic Press Inc., 2015) Jian-Hua Qiao; Vivek Mishra; Michael C. Fishbein; Satyesh K. Sinha; Tripathi B. Rajavashisth
The mechanism(s) mediating atherosclerotic calcification may be similar to those governing bone remodeling, and osteoblast-like cells have been observed in plaque. We tested the hypothesis that osteoclast-like cells (OLCs) also exist in atherosclerotic arteries. In 205 tissue blocks obtained from 21 patients undergoing carotid endarterectomy, we performed histopathologic analysis, histochemical staining for tartrate-resistant acid phosphatase (TRAP), and immunohistochemical analysis for osteoclast and macrophage antigens, including CD68, colony stimulating factor-1 receptor (CSF-1R), cathepsin K (cat-K), receptor activator of nuclear factor-κB (RANK), and osteoprotegerin (OPG). Lesions were classified according to the AHA system, and further grouped as calcified or non-calcified (with necrotic cores or suture granulomas). Multinucleated giant cells morphologically similar to osteoclasts were frequently seen, sometimes exhibited morphologic evidence of polarization, were closely associated with regions of calcification, fibrosis, or granulomatous tissue, and also appeared to be associated with neovascularization and regions of intraplaque hemorrhage. TRAP-positive cells often expressed the osteoclast-associated antigens cat-K, RANK, and OPG. Calcification typically occurred at the base of plaque or in necrotic cores in various morphologies, including a fine powdery pattern, a diffuse pattern of larger deposits near cholesterol clefts and necrotic centers, and nodular forms. Regions of frank ossification were rarely observed. Conclusion: OLCs are frequently found in plaque, and co-localize with sub-regions of cholesterol deposition, mineralization, and necrotic and foreign debris. True bone tissue is rare in carotid plaque, although more common in other arteries. Our findings suggest that arterial OLCs might degrade mineral deposits, prevent formation of calcification or both and therefore counterbalance the activity of the osteoblast-like cells in atherosclerosis. © 2015 Elsevier Inc.
Nuclear localization of catalytically active MMP-2 in endothelial cells and neurons
(E-Century Publishing Corporation, 2014) Satyesh K. Sinha; Kamlesh Asotra; Hiroyasu Uzui; Santosh Nagwani; Vivek Mishra; Tripathi B. Rajavashisth
From microscopic organelles and sub-cellular domains to the level of whole tissues, organs, and body parts, living organisms must continuously maintain and renovate structural components. Matrix metalloproteinases (MMPs) comprise a family of over two dozen Zn-dependent endopeptidases thought to be primary effectors of extracellular tissue renewal and remodeling processes. Endogenous inhibitors, particularly the tissue inhibitors of MMPs (TIMPs), counteract MMP-2 proteolytic activity, but also participate in conversion of several pro-MMPs to proteolytically active forms. Numerous pathologies are characterized by imbalances in activities of MMPs relative to TIMPs. MMPs are synthesized and stored in cytoplasmic domains prior to secretion or expression in cell surface-associated form. Several proteases have been identified in cell nuclei, but their functions, regulation, and substrates remain largely unknown. Here we showed that the catalytically active gelatinase MMP-2 is expressed in nuclei of endothelial cells and neurons, but not in glial or Schwannoma cell lines, in a pattern resembling nuclear speckles, and colocalizes with TIMP-1.
One pot synthesis and characterization of industrially important graft copolymer (GOH-g-ACM) by using peroxymonosulphate/mercaptosuccinic acid redox pair
(European Polymer Federation, 2009) Arti Srivastava; Vivek Mishra; Shailendra Kumar Singh; Rajesh Kumar
Guar gum-g-polyacrylamide is a graft copolymer which is used for many industrial applications. This paper outlines the details of synthesis of guar gum -g-acrylamide by using potassium peroxymonosulphate/ mercaptosuccinic acid redox pair in an inert atmosphere and their characterization by infrared spectroscopy, UV analysis and study of swelling and thermal properties. Grafting characteristics: %G, %E, %C, %A and %H were determined by using Fanta's definition; rate of grafting was also calculated. On studying the effect of reaction conditions on grafting characteristics, it was found that the optimum concentration of peroxymonosulphate, mercaptosuccinic acid, hydrogen ion, acrylamide and guar gum for maximum % of grafting were 8.0×10 -3, 3.2×10-3, 8.0×10-3, 16.0×10-2 mol dm-3 and 60.0×10 g dm -3 respectively. The optimum time duration and temperature of reaction were found to be 120 min and 40°C respectively. During the study [H+] variation showed prompt changes on grafting characteristics. It was found that after 310°C the Polyacrylamide grafted guar gum was thermally more stable than pure guar gum.
Preface
(CRC Press, 2024) Vivek Mishra; Syed Sibtay Razi; Ajit Kumar
[No abstract available]
RAFT polymerization of N-vinyl pyrrolidone using prop-2-ynyl morpholine-4-carbodithioate as a new chain transfer agent
(2012) Vivek Mishra; Rajesh Kumar
RAFT polymerization of N-vinyl pyrrolidone (NVP) has been investigated in the presence of chain transfer agent (CTA), i.e., prop-2-ynyl morpholine-4-carbodithioate (PMDC). The influence of reaction parameters such as monomer concentration [NVP], molar ratio of [CTA]/[AIBN, i.e., 2,2′-azobis (2-methylpropionitrile)] and [NVP]/[CTA], and temperature have been studied with regard to time and conversion limit. This study evidences the parameters leading to an excellent control of molecular weight and molar mass dispersity. NVP has been polymerized by maintaining molar ratio [NVP]: [PMDC]: [AIBN] = 100: 1: 0.2. Kinetics of the reaction was strongly influenced by both temperature and [CTA]/[AIBN] ratio and to a lesser extent by monomer concentration. The activation energy (E a = 31.02 kJ mol -1) and enthalpy of activation (δH †= 28.29 kJ mol -1) was in a good agreement to each other. The negative entropy of activation (δS † = -210.16 J mol -1K -1) shows that the movement of reactants are highly restricted at transition state during polymerization. Copyright © 2011 Wiley Periodicals, Inc.
Role of macrophage colony-stimulating factor in the development of neointimal thickening following arterial injury
(Elsevier Inc., 2016) Vivek Mishra; Satyesh K. Sinha; Tripathi B. Rajavashisth
Evidence suggests that macrophage colony-stimulating factor (M-CSF) participates critically in atherosclerosis; little is known about the role of M-CSF in the development of neointimal hyperplasia following mechanical vascular injury. We examined the expression of M-CSF and its receptor, c-fms, in rodent and rabbit models of arterial injury. Injured rat carotid arteries expressed 3- to 10-fold higher levels of M-CSF and c-fms mRNA and protein following balloon injury as compared to uninjured arteries. In the rabbit, M-CSF protein expression was greatest in neointimal smooth muscle cells (SMCs) postinjury, with some expression in medial SMCs. M-CSF-positive SMCs exhibited markers of proliferation. At 30 days postinjury, neointimal SMCs in the adjacent healed area near the border between injured and uninjured zone lost both proliferative activity and overexpression of M-CSF. The presence of induced M-CSF and c-fms expression correlated with the initiation of SMCs proliferation. M-CSF stimulated incorporation of [3H] thymidine in human aortic smooth muscle cells in a concentration-dependent manner. Serum-free conditioned medium from aortic SMCs also promoted DNA synthesis, and this effect was blocked by M-CSF specific antibody. To test further the role of M-CSF in vivo, we induced arterial injury by placing a periadventitial collar around the carotid arteries in compound mutant mice lacking apolipoprotein apoE (apoE-/-) and M-CSF. Loss of M-CSF abolished the neointimal hyperplastic response to arterial injury in apoE-/- mice. Local delivery of M-CSF to the injured artery restored neointimal proliferation, suggesting a critical role of M-CSF for the development of neointimal thickening following arterial injury. © 2016 Elsevier Inc. All rights reserved.
Synthesis and characterization of five-arms star polymer of N-vinyl pyrrolidone through ATRP based on glucose
(2011) Vivek Mishra; Rajesh Kumar
Glucose based five arms atom transfer radical polymerization initiator was synthesized. This initiator was used to synthesize 5-arms star polymer of N-vinyl pyrrolidone (NVP) through controlled radical polymerization. The ratio of reactants were kept as 1:1:2: 200 (initiator:Cu(I)Br:bpy:NVP). The rate of reaction with respect to NVP was found to be first order, and number-average molecular weight increases linearly with temperature up to 90 °C. The activation energy (Ea = 29.75 kJ mol-1) and enthalpy (ΔH‡ = 26.73 kJ mol-1) were found to be in a good agreement with each other for activated complex, and negative value of entropy of activation (ΔS‡ = -219.12 J mol-1 K-1) supports the highly ordered transition state. © 2010 Elsevier Ltd. All rights reserved.
Synthesis, In-Silico Molecular Docking Studies, and In-Vitro Antimicrobial Evaluation of Isatin Scaffolds bearing 1, 2, 3-Triazoles using Click Chemistry
(Springer, 2024) Ritesh Anand; Nisha Yadav; Deeksha Mudgal; Simran Jindal; Sunak Sengupta; Deepak Kumar; Jay Singh; Nagendra Kumar Panday; Vivek Mishra
Bacterial infections continue to present a formidable challenge to human health, prompting intensified research efforts towards the development of effective antibacterial agents. This study harnesses click chemistry techniques to synthesize Isatin-1,2,3-triazole as a novel antibacterial agent, evaluating its in vitro efficacy against prevalent pathogens including Gram-negative (Escherichiacoli) and Gram-positive (Staphylococcusaureus) strains using both the microdilution and well-diffusion methods. The findings reveal a notable enhancement in antibacterial activity upon incorporation of the triazole moiety into the Isatin framework against both E. coli and S. aureus. Further analysis, including structure–activity relationship studies and molecular docking investigations, highlights the superior antibacterial potency of triazole-tethered Isatin tosyl azide compared to N-propargyl Isatin. Molecular docking simulations with Staphylococcusaureus (PDB ID: 4TU5) and Escherichiacoli (PDB ID: 6YD9) proteins exhibit promising binding affinities of − 10.44 kJ/mol and − 8.4 kJ/mol, respectively. Isatin triazole demonstrates favorable gastrointestinal absorption properties, low toxicity profiles, adherence to Lipinski's rule of five, and compliance with Veber and Ghose standards. Furthermore, molecular dynamics simulations attest to the stability of protein complexes over a 100 ns timeframe. Collectively, these findings underscore the therapeutic potential of Isatin triazole compounds against bacterial infections, warranting further clinical exploration to elucidate their mechanisms of action and therapeutic efficacy. Graphical Abstract: (Figure presented.) © Association of Microbiologists of India 2024.
Synthesis, In-Silico Molecular Docking Studies, and In-Vitro Antimicrobial Evaluation of Isatin Scaffolds bearing 1, 2, 3-Triazoles using Click Chemistry
(Springer, 2025) Ritesh Anand; Nisha Yadav; Deeksha Mudgal; Simran Jindal; Sounok Sengupta; Deepak Kumar; Jay Singh; Nagendra Kumar Panday; Vivek Mishra
Bacterial infections continue to present a formidable challenge to human health, prompting intensified research efforts towards the development of effective antibacterial agents. This study harnesses click chemistry techniques to synthesize Isatin-1,2,3-triazole as a novel antibacterial agent, evaluating its in vitro efficacy against prevalent pathogens including Gram-negative (Escherichiacoli) and Gram-positive (Staphylococcusaureus) strains using both the microdilution and well-diffusion methods. The findings reveal a notable enhancement in antibacterial activity upon incorporation of the triazole moiety into the Isatin framework against both E. coli and S. aureus. Further analysis, including structure–activity relationship studies and molecular docking investigations, highlights the superior antibacterial potency of triazole-tethered Isatin tosyl azide compared to N-propargyl Isatin. Molecular docking simulations with Staphylococcusaureus (PDB ID: 4TU5) and Escherichiacoli (PDB ID: 6YD9) proteins exhibit promising binding affinities of − 10.44 kJ/mol and − 8.4 kJ/mol, respectively. Isatin triazole demonstrates favorable gastrointestinal absorption properties, low toxicity profiles, adherence to Lipinski's rule of five, and compliance with Veber and Ghose standards. Furthermore, molecular dynamics simulations attest to the stability of protein complexes over a 100 ns timeframe. Collectively, these findings underscore the therapeutic potential of Isatin triazole compounds against bacterial infections, warranting further clinical exploration to elucidate their mechanisms of action and therapeutic efficacy. © Association of Microbiologists of India 2024.
To Study the Incidence of Biofilm Formation, its Microbiology and its Effect on the Development of Acute and Chronic Rhinosinusitis- A Prospective Study
(Springer, 2025) Akshat Pandey; Ramraj Yadav; Vivek Mishra; Akanksha Sharma; Sanjay Kumar Saroj; Rahul Yadav; Jeffrey Oswin Rynjah; Srishti Bhansali; Anjalika Sharma; Gundra Chandra Shekar; Sishupal Yadav; Arpit Goyal; Ragini Tilak; Sushil Kumar Aggarwal
Bacterial biofilms are organised complex structures having polymicrobial nature in a single community, which provide protection to bacteria from antibiotics by various means. The aim of our study was to determine the prevalence of biofilm-forming bacteria in clinical isolates of acute and chronic rhinosinusitis (ARS and CRS) patients with sinonasal mucopurulence. To know the incidence of bacterial biofilms in patient with ARS and CRS, to study the microbiology of bacterial biofilms in ARS and CRS, to assess the role and effects of biofilm in ARS and CRS and to correlate the association between the formation of the biofilm and development of rhinosinusitis. This prospective study was carried out at a tertiary care centre in Eastern part of India, in which 60 patients were taken as sample size. All patients of rhinosinusitis between age-group of 10 to70 years, who came to our out-patient department, were taken for our study. Biofilm formation was observed in 50% cases and were absent in 50% cases of chronic rhinosinusitis in our study. 83.3% (50) of patients out of 60 patients got improved after treatment and recurrence was observed in only 16.6% (10) of patients. Recurrence was more at 3 months follow-up as compared to follow-up at 1 month, though it was not statistically significant. Though our study highlighted the incidence and role of biofilms in the development of chronic rhinosinusitis, but few more randomized controlled studies involving larger sample sizes should be done to exactly determine the pathophysiological role of biofilms in the development and recurrence of acute and chronic rhinosinusuitis. © Association of Otolaryngologists of India 2024.
Uptake of hazardous heavy metal ions by aqueous solution of poly(acrylamide) prepared through atom transfer radical polymerization process
(2013) Vivek Mishra; Rajesh Kumar
Poly(acrylamide) (PACM) used in this study was prepared through an effective atom transfer radical polymerization process and characterized by NMR, FTIR, and thermo gravimetric analysis. Resulting polymer was used for the uptake of heavy metal ions from aqueous solution. Partition coefficient, retention capacity, and metal ion uptake behavior in aqueous solution of PACM at different monomer percent conversions and effect of parameters for optimization of polymerization reaction gives thermally stable PACM. Efficiency of metal ion uptake of different molecular weights of PACM were tested in batches for Ni2+, Pb2+, Cu2+, Zn2+, and Hg 2+ ions in single metal solution. Metal ion sorption capacities increase with increase in polymer concentration. Metal ion sorption capacities in single metal system were 6.3 mg g-1 Ni2+, 6.0 mg g -1 Pb2+, 6.9 mg g-1 Cu2+, 6.2 mg g-1 Zn2+, 22.4 mg g-1 Hg2+ for PACM of 88% conversion (Mn = 19,850). Uptake by the PACM indicates that they are effective in removing metal ions from single metal ion solutions. © 2012 Wiley Periodicals, Inc.