Browsing by Author "Arvind Kumar"

Now showing 1 - 20 of 122

A study on CoFe/p-Si interfacial structures before and after swift heavy ion irradiation
(Bellwether Publishing, Ltd., 2015) Arvind Kumar; P.C. Srivastava
Interfacial structures of CoFe/p-Si have been studied before and after the swift heavy ion (∼100 MeV, Ni7+) irradiation to investigate its electronic and magnetic behavior. X-ray diffraction (XRD), atomic force microscopy, magnetic force microscopy and magnetization characteristics (M-H) from vibrating sample magnetometer (VSM) techniques have been used for the above. XRD data have confirmed the formation of the CoFe alloy phase along with the silicide phases of Fe and Co. It is observed that there is an irradiation-induced growth in crystallite but surface remains smooth with a surface roughness of ∼34 nm. A very significant increase has been observed in the magnetization and that too with irradiation dose as compared with unirradiated ones, maintaining their superparamagnetic behavior. The results could be understood due to the role played by various magnetic phases in the structure. The magnetic field sensitivity on electronic transport across the structures has also increased in a significant manner after the irradiation as compared with unirradiated ones. The magnetic field sensitivity has resulted in an MR of 20%. The results could be understood due to the irradiation induced interfacial intermixing to result in increased magnetic phases of silicide for the observed significant magnetic behavior on the irradiation. © 2015 Taylor & Francis.
Ab initio modeling and ligand docking of quercetin and the MC-LR transporter protein Oatp1b2/OATP1B3
(Elsevier B.V., 2023) Kriti Shrinet; Ritika K. Singh; Riden Saxena; Avinash K. Chaurasia; Arvind Kumar
Trans-membrane proteins (TMPs) play a crucial role in the translocation of organic and inorganic molecules. Unlike other proteins, TMPs are difficult to model structurally because of their location within the amphipathic plasma membrane. In this study, we focused on examining the transport of the cyanotoxin microcystin-LR (MC-LR) through organic ion transporting polypeptides (OATPs) and whether the bioactive phytoconstituent quercetin can function as a barrier to the transportation of MC-LR. To test this hypothesis, we first modeled the transporters OATP1B3 and Oatp1b2 localized in the human and mouse liver, respectively, by ab initio modeling with the Iterative Threading ASSEmbly Refinement server and refined the generated model using the refinement tool of the ModLoop server. Using different tools and servers, the structural quality of the transmembrane helices was validated and found to be an accurate structure of a TMP. Docking analysis was performed with the ligands MC-LR and quercetin with both OATPs using the PatchDock and FireDock online servers. The results, in the form of the global energy of both docked structures, were based on predictions made earlier. The Oatp1b2 global energy for quercetin was −36.4 kcal/mol, compared with the corresponding value at the MC-LR location which was only −5.59 kcal/mol. Similarly, in the case of OATP1B3 with quercetin, the global energy was found to be −39.0 kcal/mol, whereas with MC-LR it was −15.6 kcal/mol. These results clearly show that quercetin competitively inhibits the binding of MC-LR to its respective targets. © 2023 The Authors
Ab initio modeling of human IRS1 protein to find novel target to dock with drug MH to mitigate T2DM diabetes by insulin signaling
(Springer Science and Business Media Deutschland GmbH, 2024) Ritika Kumari Singh; Avinash Kumar Chaurasiya; Arvind Kumar
IRS1 is a cytoplasmic adaptor protein that helps in cellular growth, glucose metabolism, proliferation, and differentiation. Highly disordered (insulin receptor substrate 1) IRS1 protein sequence (mol.wt- 131,590.97 da) has been used to develop model using ab initio modeling technique by I-Tassar tool and Discovery Studio/ DogSite Server to decipher a novel active site. The constructed protein model has been submitted with PMDB Id- PM0082210. GRAVY index of IRS1 model (− 0.675) indicated surface protein–water interaction. Protparam tool instability index (75.22) demonstrated disorderedness combined with loops owing to prolines/glycines. After refinement, the Ramachandran plot showed that 88 percent of AAs were present in the allowed region and only 0.5% in the disallowed region. Novel IRS1 model protein has 10 α-helices, 22 β-sheets, 20 β-hairpins, 5 β-bulges, 47 strands, 105 β-turns, and 8 γ-turns. Docking of IRS1 with drug MH demonstrated interaction of Ser-70, Thr-18, and Pro-69 with C–H bonds; Gln-71, and Glu-113 with hydrogen bonds; while both Glu-114 and Glu-113 with salt-bridge connection. Permissible 1.0–1.5 Å range of RMSD fluctuation between 20 and 45 ns was obtained in simulation of IRS1 and IRS1-met complex confirmed that both complexes were stable during whole simulation process. RMSF result showed that except positions 57AA and 114AA, the binding of drug had no severe effects on the flexibility of the IRS1 and IRS1-met complex. The RoG value of compactness and rigidity showed little change in IRS1 protein. SASA value of IRS1 indicated non-significant fluctuation between IRS1 and drug MH means ligand (drug) and IRS1 receptor form stable structure. Hydrogen bond strength of IRS1 and IRS1-met was 81.2 and 76.4, respectively, which suggested stable interaction. © King Abdulaziz City for Science and Technology 2024.
Addition of Crop Residues with Different C:N Ratios on the Release Pattern of Available Nitrogen and Sulfur in Different Soils
(Taylor and Francis Ltd., 2021) Sreejan Singh; P.K. Sharma; Surendra Singh; Arvind Kumar
Mineralization of organic N and S of crop residue is an important useful tool for forecasting availability of N and S in soils. Three different soils (Vertisol, Inceptisol and Alfisol) from eastern Uttar Pradesh, India; seven crops residue, four cereals (rice, barley, maize, wheat) from irrigated area of Varanasi; and three pulses (gram lentil, pigeon pea) from rainfed area of Mirzapur were used in 90-day incubation study under controlled condition to estimate the release of soil available N and S. The experiment was laid out in a factorial completely randomized design with three replications. Total Nitrogen (N) and total Sulfur (S) contents were higher in the pulses than that of cereals. Pulses residue with the lowest C:N:S ratio (177.0:3.7:1 to 195.8:4.5:1) had significantly rapid rate of N and S release up to 45 days and then declined at 60 and 90 days. On the other hand, cereals with the highest C:N:S ratio (390.8:4.3:1 to 463.6:5.0:1) had slow release of N and S up to 45 days and then rapid released at 60 and 90 days. Among pulses residue, pigeon pea has resulted significantly higher net release of soil available N and S at day 45 to the extent of 18.4 and 78.7% in Alfisol, 17.7 and 51.2% in Inceptisol, and 15.0 and 24.1% in Vertisol, respectively, over control. Among the cereals residue, barley residue amended Alfisol had higher net increase in available N at day 90 (13.2%) followed by Inceptisol (10.8%) and Vertisol (9.9%) over control. © 2021 Taylor & Francis Group, LLC.
An efficient oxidation of alcohols using a new trinuclear copper complex as a reusable catalyst under solvent free conditions
(Royal Society of Chemistry, 2014) Rosmita Borthakur; Mrityunjaya Asthana; Mithu Saha; Arvind Kumar; Amarta Kumar Pal
A new trinuclear copper(ii) complex [Cu3(L)(μ2-Cl) 2(H2O)6] was synthesized and characterized by various spectroscopic techniques. The trinuclear complex was demonstrated as an efficient catalyst for the selective oxidation of primary, secondary, aliphatic, heteroatomic and conjugated allyl alcohols to the corresponding aldehydes/ketones in good to excellent yields under solvent free conditions using H2O2 as an oxidant. The catalyst is easily synthesizable, easy to handle and reusable up to eight runs. This journal is © the Partner Organisations 2014.
Analysis of physico-chemical characteristics of pauttika honey procured from Uttar Pradesh, India
(Enviro Research Publishers, 2020) Veena; Vandana Verma; Amala Udayakumar; Shikha Pandhi; Arvind Kumar; Vinod Kumar Paswan
Background of the Study: Ayurveda has described eight kinds of honey with the different medicinal values that get change with the passage of time of one year. Pauttika honey is a specific kind of honey among the eight types of honey produced by Pauttika honey bee, which is indicated in the management of diabetes (Prameha), obesity (Sthaulaya), dyslipidemia, etc. Objective: To identify and standardize the type of honey and its honey bee on scientific parameters and the characteristics as mentioned in Ayurveda. Materials and Methods: Honey was procured from the natural honey hive and Standard methods were used for physico-chemical analysis, sensory evaluation, and color hunter test. Bee identification was done by an expert entomologist. Results: Analysis of honey, showed that procured honey was Pauttika type of honey as described in Ayurveda and bee was identified as Apis dorsata. Researchers also found some changes in the properties of honey after the one year like in pH, HMF, Color, and Sensory evaluation. Conclusion: The Physico-chemical analysis of honey samples confirmed the good quality of Pauttika honey produced by Apis dorsata also confirms a new variety of honey as mentioned in Ayurveda. © 2020 The Author(s). Published by Enviro Research Publishers.
Antialgal activity of a hepatotoxin-producing cyanobacterium, Microcystis aeruginosa
(2001) Dhananjaya P. Singh; M.B. Tyagi; Arvind Kumar; J.K. Thakur; Ashok Kumar
Antimicrobial activity of toxin produced by a freshwater bloom-forming cyanobacterium Microcystis aeruginosa has been studied. When tested against certain green algae, cyanobacteria, heterotrophic bacteria and fungi, the toxin inhibited growth of only green algae and cyanobacteria. The toxin has been partially purified employing Thin layer chromatography (TLC) and High-performance liquid chromatography (HPLC) techniques and appears to be microcystin-LR (leucine-arginine). Both crude and purified toxins showed toxicity to mice, the clinical symptoms in test mice being similar to those produced by hepatotoxin. Purified toxin at a concentration of 50 μg ml-1 caused complete inhibition of growth followed by cell lysis in Nostoc muscorum and Anabaena BT1 after 6 days of toxin addition. Addition of toxin (25 μg ml-1) to the culture suspensions of the Nostoc and Anabaena strains caused instant and drastic loss of O2 evolution. Furthermore a marked reduction (about 87%) in the 14CO2 uptake was also observed at a concentration of 50 μg ml-1. Besides its inhibitory effects on photosynthetic processes, M. aeruginosa toxin (50 μg ml-1) also caused 90% loss of nitrogenase activity after 8 h of its addition. Experiments performed with 14C-labelled toxin indicate that the toxin uptake by cyanobacterial cells occurs both in light and dark. These results demonstrate that the toxin is strongly algicidal and point to the possibility that it may have an important role in establishment and maintenance of toxic blooms of M. aeruginosa in freshwater ecosystems. The relative significance of the hepatotoxic effect and the algicidal effect of the toxin is discussed with reference both to survival and dominance of M. aeruginosa in nature.
Antimicrobial properties of black grape (Vitis vinifera L.) peel extracts against antibiotic-resistant pathogenic bacteria and toxin producing molds
(Medknow Publications, 2015) Devbrat Yadav; Arvind Kumar; Pramod Kumar; Diwaker Mishra
Aim: Black grape peel possesses a substantial amount of polyphenolic antimicrobial compounds that can be used for controlling the growth of pathogenic microorganisms. The purpose of this study was to assess antibacterial and antifungal activity of black grape peel extracts against antibiotic-resistant pathogenic bacteria and toxin producing molds, respectively. Materials and Methods: Peel of grape was subjected to polyphenolic extraction using different solvents viz., water, ethanol, acetone, and methanol. Antibiotic-resistant strains of Staphylococcusaureus,Enterococcusfaecalis, Enterobacteraerogenes,Salmonella typhimurium, and Escherichiacoli were screened for the antibacterial activity of different grape extracts. Antibacterial activity was analyzed using agar well diffusion method. Penicilliumchrysogenum, Penicilliumexpansum, AspergillusNiger and Aspergillusversicolor were screened for the antifungal activity. Antifungal activity was determined by counting nongerminated spores in the presence of peel extracts. Results: As compared to other solvent extracts, methanol extracts possessed high antibacterial and antifungal activity. S.typhimurium and E. coli showed complete resistance against antibacterial action at screened concentrations of grape peel extracts. Maximum zone of inhibition was found in case of S.aureus, i.e., 22 mm followed by E.faecalis and E.aerogenes, i.e., 18 and 21 mm, respectively, at 1080 mg tannic acid equivalent (TAE)/ml. The maximum and minimum percent of growth inhibition was shown by P.expansum and A.Niger as 73% and 15% at 1080 TAE/ml concentration of grape peel extract, respectively. Conclusions: Except S.typhimurium and E.coli, growth of all bacterial and mold species were found to be significantly (P < 0.05) inhibited by all the solvent extracts. © 2015 Indian Journal of Pharmacology Published by Wolters Kluwer.
Antineoplastic and immunomodulatory effect of polyphenolic components of Achyranthes aspera (PCA) extract on urethane induced lung cancer in vivo
(2014) Chandradeo Narayan; Arvind Kumar
Polyphenolic compounds of Achyranthes aspera (PCA) extract is evaluated for anti-cancerous and cytokine based immunomodulatory effects. The PCA extract contains known components of phenolic acid and flavonoids such as mixture of quinic acid, chlorogenic acid, kaempferol, quercetin and chrysin along with many unknown components. PCA has been orally feed to urethane (ethyl carbamate) primed lung cancerous mice at a dosage of 100 mg/kg body weight for 30 consecutive days. 100 mg powder of A. aspera contains 2.4 mg phenolic acid and 1.1 mg flavonoid (2:1 ratio). Enhanced activities and expression of antioxidant enzymes GST, GR, CAT, SOD, while down regulated expression and activation of LDH enzymes in PCA feed urethane primed lung cancerous tissues as compared to PCA non-feed urethane primed lung cancerous tissues were observed. PCA feed urethane primed lung tissues showed down regulated expression of pro-inflammatory cytokines IL-1β, IL-6 and TNF-α along with TFs, NF-κB and Stat3 while the expression of pro-apoptotic proteins Bax and p53 were enhanced in PCA feed urethane primed lung tissues. FTIR and CD spectroscopy data revealed that PCA resisted the urethane mediated conformational changes of DNA which is evident by the shift in guanine and thymine bands in FTIR from 1,708 to 1,711 cm-1 and 1,675 to 1,671 cm-1, respectively in PCA feed urethane primed lung cancerous tissues DNA in comparison to urethane primed lung cancerous tissues DNA. The present study suggests that PCA components have synergistic anti-cancerous and cytokine based immunomodulatory role and DNA conformation restoring effects. However, more research is required to show the effects of each component separately and in combination for effective therapeutic use to cure and prevent lung cancer including other cancers. © 2013 Springer Science+Business Media Dordrecht.
Appropriate solvents for extracting total phenolics, flavonoids and ascorbic acid from different kinds of millets
(Springer, 2015) Rohit Upadhyay; Alok Jha; Satyendra P. Singh; Arvind Kumar; Mithilesh Singh
Different polar solvents (methanol, acetone and water) were tested for their extractability of phenolic compounds from millets grown in India namely, sawan (Echinochloa frumentacea), kodo (Paspalum scrobiculatum), jowar (Sorghum bicolor) and bajra (Pannisetum typhoides). The extracts were evaluated for their total phenolics, flavonoids, ascorbic acid content and antioxidant activity. The acetone extracts reported highest total phenolics content (TPC) between 0.8 and 2.64 mg gallic acid equivalents/g flour dry matter; the lowest for sawan and the highest for bajra. Ascorbic acid content did not differ significantly between different millets (p < 0.05) except for sawan (lowest). The antioxidant assays included 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical (OH*) scavenging and reducing power. The activity in millets followed as bajra > jowar > kodo > sawan. The polyphenols in extracts were also analyzed by high-performance liquid chromatography (HPLC) at 290 nm. A clear correlation obtained between the TPC, flavonoids content and antioxidant activity. Acetone showed better extractability and thus can be appropriate solvent to extract phenolic compounds in millets used in this study. © 2013, Association of Food Scientists & Technologists (India).
Augmenting progress on the elimination of vertical transmissions of HIV in India: Insights from Spectrum-based HIV burden estimations
(Public Library of Science, 2023) Pradeep Kumar; Chinmoyee Das; Udayabhanu Das; Arvind Kumar; Nidhi Priyam; Varsha Ranjan; Damodar Sahu; Sanjay K. Rai; Sheela V. Godbole; Elangovan Arumugam; P.V.M. Lakshmi; Shanta Dutta; H. Sanayaima Devi; Arvind Pandey; Dandu Chandra Sekhar Reddy; Sanjay Mehendale; Shobini Rajan
The government of India has adopted the elimination of vertical transmission of HIV as one of the five high-level goals under phase V of the National AIDS and STD Control Programme (NACP). In this paper, we present the data from HIV estimations 2021 for India and select States detailing the progress as well as the attributable causes for vertical transmissions. The NACP spearheads work on mathematical modelling to estimate HIV burden based on the periodically conducted sentinel surveillance for guiding program implementation and pol-icymaking. Using the results of the latest round of HIV Estimations in 2021, we analysed the mother-to-child transmission (MTCT) during the perinatal and postnatal (breastfeeding) period. In 2021, overall, around 5,000 [3,000–7,800] vertical transmissions were estimated nationally with 58% being perinatal infections and remaining during breastfeeding. MTCT at 6 weeks was around 12.95% [9.45–16.02] with the final transmission rate at 24.25% [18.50–29.50]. Overall, 57% of vertical transmissions were among HIV-positive mothers who did not receive ART during pregnancy or breastfeeding, 19% among mothers who dropped off ART during pregnancy or delivery, and 18% among mothers who were infected during pregnancy or breastfeeding. There were significant variations between States. Depending upon the States, the programme needs to focus on the intervention domains of timely engagement in antenatal care-HIV testing-ART initiation as well as programme retention and adherence support. Equally important would be strengthening the strategic information to generate related evidence for inputting India and State-specific parameters improving the MTCT-related modelled estimates. © 2023 Kumar et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Bioactive compounds and their future therapeutic applications
(Elsevier, 2020) Kriti Shrinet; Ritika K. Singh; Avinash K. Chaurasia; Alok Tripathi; Arvind Kumar
Natural bioactive compounds, plant secondary metabolites, are not necessary for the normal survival of the plants but required for inter- or intragenus/species competition, defense, attraction, and signaling in plants. These compounds play a crucial role in the life of animals with having great potential for human well-fare, mostly with pharmacological or toxicological effects, against microbial pathogens and diseases including cancer in humans and animals. Bioactive compounds involve a broad variety of chemical structures and functions that facilitate a better way for the production of nutraceuticals, functional foods, and food additives. Some bioactive compounds found in nature are significantly high in concentration such as polyphenols; examples are phenolic compounds, flavonoids, anthocyanidins, flavans, tannins, and so on, and other concentrations are nonsignificant, but with high commercial values. Bioactive compounds have diverse pharmacological activities and applications for treatment of many diseases. These compounds act as antidiabetic, antipyretic, anticancerous, antidiuretic, antiatherosclerotic, and so on for the human beings. However, the inherent difficulties in screening and manufacturing these compounds have led to the development of advanced technologies. Frequently used methods for their extraction from plants and their parts are the conventional liquid-liquid or solid-liquid extraction, and the advanced methods include pressurized-liquid extraction, subcritical, and supercritical extractions and microwave- and ultrasound-assisted extractions. Extracted compounds are further characterized by MALDI-TOF-MS based on their specific absorption spectra to be used for the formulation of various drugs. © 2021 Elsevier Inc.
Bioactive metabolites identification of the foxnut and broken millet-based nutritional bar using HR-MS
(Elsevier B.V., 2024) Vishal Kumar; Arvind Kumar; Manish Kumar Singh; Priya Dhyani; Himanshu Mishra; Dinesh Chandra Rai
The by-products of the grain processing industry are a vital resource for the valorization methods in the food industry. In comparison to the whole grain, the broken kernels and seeds own similar nutrient and bioactive compounds having multifaceted health properties. This study aims to develop a nutritional bar by utilizing the by-products from barnyard millet and foxnut with added sweeteners. Furthermore, high-resolution mass spectrometry (HR-MS) metabolomics was carried out in positive and negative both ion modes to identify the major bioactive compounds formed in the matrix of the best-optimized valorized bar. The formulation of the bar having 15 % foxnut flour and the barnyard flour each, was elucidated highest rheological and sensory scores. A sum of 29 bioactive metabolites has been observed in the obtained metabolome. Major metabolites were palmitoyl serinol, glycitein, persin, bufagargarizin, apigenin, carvone, etc. covering a wide area in the mass spectrum. The therapeutic value of these compounds is heart health promotion, anti-inflammatory, anti-carcinogenic, anti-diabetic, anti-microbial, etc. This work highlights the bioactivity of the valorized nutritional bar employing robust and accurate tool of mass spectrometry. The developed snack is a functional food for the consumers. © 2024 The Author(s)
Breeding strategies for improved multistress-resilient crops
(Springer Nature, 2025) B. M. Lokeshkumar; Sanchika Snehi; Krishanu; S. Dasaratha Kumar; Kuram Tirumala Ravikiran; Rahul Kumar; Mukesh Choudhary; Suneetha Kota; Arvind Kumar; Anita Mann; Satish Kumar Sanwal; Nitish Ranjan Prakash
Multiple stresses including abiotic and biotic, affecting crop plants are more common nowadays in the era of climate change. These stresses include several abiotic stresses such as drought, salinity, cold, heat, mineral deficiency, mineral toxicity, and waterlogging and biotic stresses such as diseases, pests, insects, and weeds. Breeding suitable cultivars with the capacity to endure multiple stresses are need of the hour. The approaches in the past were conventional pedigree-based selection, backcross-assisted introgression and transfer, and recombination breeding. However, in the recent past, the marker-assisted backcross breeding (MABB) approach has been used successfully to transfer multiple abiotic and biotic stress-tolerant oligogenic/major QTLs from donor genotypes into elite lines. Presently, with the advent of robust and cheaper genotyping costs, the capability to analyze big data, high computational efficiency, and the use of rapid generation techniques (Speed Breeding), genomic selection has emerged as a major player in breeding. Genomic selection breeding pipelines are very robust in predicting the performance of genotypes. The present chapter summarizes a thorough understanding of conventional and molecular breeding approaches to develop multistress-tolerant crop varieties. © Springer Nature Singapore Pte Ltd. 2025. All rights reserved.
Cd-induced cytosolic proteome changes in the cyanobacterium Anabaena sp. PCC7120 are mediated by LexA as one of the regulatory proteins
(Elsevier B.V., 2023) Akanksha Srivastava; Arvind Kumar; Subhankar Biswas; Vaibhav Srivastava; Hema Rajaram; Yogesh Mishra
LexA, a well-characterized transcriptional repressor of SOS genes in heterotrophic bacteria, has been shown to regulate diverse genes in cyanobacteria. An earlier study showed that LexA overexpression in a cyanobacterium, Anabaena sp. PCC7120 reduces its tolerance to Cd stress. This was later shown to be due to modulation of photosynthetic redox poising by LexA under Cd stress. However, due to the global regulatory nature of LexA and the prior prediction of AnLexA-box in a few heavy metal-responsive genes, we speculated that LexA has a broad role in Cd tolerance, with regulation over a variety of Cd stress-responsive genes in addition to photosynthetic genes. Thus, to further expand the knowledge on the regulatory role of LexA in Cd stress tolerance, a cytosolic proteome profiling of Anabaena constitutively overexpressing LexA upon Cd stress was performed. The proteomic study revealed 25 differentially accumulated proteins (DAPs) in response to the combined effect of LexA overexpression and Cd stress, and the other 11 DAPs exclusively in response to either LexA overexpression or Cd stress. The 36 identified proteins were related with a variety of functions, including photosynthesis, C-metabolism, antioxidants, protein turnover, post-transcriptional modifications, and a few unknown and hypothetical proteins. The regulation of LexA on corresponding genes, and six previously reported Cd efflux transporters, was further validated by the presence of AnLexA-boxes, transcript, and/or promoter analyses. In a nutshell, this study identifies the regulation of Anabaena LexA on several Cd stress-responsive genes of various functions, hence expanding the regulatory role of LexA under Cd stress. © 2023 Elsevier B.V.
CGA mitigates HMGB1 mediated TLR4 activated hepatic cancer in urethane primed mice
(Elsevier B.V., 2024) Alok Tripathi; Kriti Shrinet; Arvind Kumar
Background: Liver cancer is fourth leading cause of cancer deaths worldwide. Urethane presents in herbicides, pesticides and food beverages as preservatives upregulate the expression of inflammatory cytokines in liver tissues for the genesis of cancer. It also naturally formed in fermented food products and distilled beverages. Study design: Balb/c mice of approx same age and body weight were selected and divided into four groups G-I (PBS treated), G-II (urethane of 500 mg/kgb.w.), G-III (CGA of 50 mg/kg b.w.) and G-IV (urethane & CGA). Treatments were given on alternate day upto eight consecutive weeks and 3-12 month of latency period. Blood sample collected was used for counting of inflammatory immune cells by automated cell counter. Total RNA and protein samples isolated from dissected liver of sacrificed mice were used for molecular analysis at transcriptional and translational level. Methods: Gene expression is assessed by RT-PCR at transcriptional level and by western blot at translational level. Immunological effects are evaluated by counting inflammatory immue cells and histopathology is done to examine hepatic tissues injury by carcinogen urethane. Hypothesis and purpose: Inflammatory cytokines create microenvironment for tumor initiation and development which is mediated through TLR-4 pathway activation via HMGB1 upon carcinogen exposure. Here aimed to find out the role of Chlorogenic acid (CGA) a phenolic compound naturally present in plants as anti-cancerous properties to prevent and cure cancer by acting upon HMGB1 & TLR4 pathway. Results: At transcriptional level up-regulated expression of HMGB1, TLR-4 pathway genes, pro-inflammatory cytokines IL-1β, IL-6, TNF-α and IL-18 in urethane treated mice is observed. Western blot results showed up-regulated expression of HMGB1 and NF-κB protein at translational level. CGA treated mice liver showed down-regulated expression of these inflammatory molecules. Increased number of inflammatory immune cells and presence of hepatic tissues injury in histopathological slides is observed in urethane treated mice that is mitigated by CGA. Conclusion: CGA is an important anti-cancerous bioactive compound targets inflammatory cytokines and HMGB1 at molecular level to prevent, cure and mitigate liver cancer. Down regulated expression of HMGB1 and TLR-4 activation pathway in cancerous Balb/c mice liver proved its anti-cancerous properties to become a potential future drug. © 2024
Citrinin Mycotoxin Contamination in Food and Feed: Impact on Agriculture, Human Health, and Detection and Management Strategies
(MDPI, 2022) Madhu Kamle; Dipendra Kumar Mahato; Akansha Gupta; Shikha Pandhi; Nitya Sharma; Bharti Sharma; Sadhna Mishra; Shalini Arora; Raman Selvakumar; Vivek Saurabh; Jyoti Dhakane-Lad; Manoj Kumar; Sreejani Barua; Arvind Kumar; Shirani Gamlath; Pradeep Kumar
Citrinin (CIT) is a mycotoxin produced by different species of Aspergillus, Penicillium, and Monascus. CIT can contaminate a wide range of foods and feeds at any time during the pre-harvest, harvest, and post-harvest stages. CIT can be usually found in beans, fruits, fruit and vegetable juices, herbs and spices, and dairy products, as well as red mold rice. CIT exerts nephrotoxic and genotoxic effects in both humans and animals, thereby raising concerns regarding the consumption of CIT-contaminated food and feed. Hence, to minimize the risk of CIT contamination in food and feed, understanding the incidence of CIT occurrence, its sources, and biosynthetic pathways could assist in the effective implementation of detection and mitigation measures. Therefore, this review aims to shed light on sources of CIT, its prevalence in food and feed, biosynthetic pathways, and genes involved, with a major focus on detection and management strategies to ensure the safety and security of food and feed. © 2022 by the authors. icensee MDPI, Basel, Switzerland.
Constitutive over expression of IL-1β, IL-6, NF-κB, and Stat3 is a potential cause of lung tumorgenesis in urethane (ethyl carbamate) induced Balb/c mice
(2012) Chandradeo Narayan; Arvind Kumar
Background: Lung cancer is a leading cause of cancer death. There has been found a substantial gap in the understanding of lung cancer genesis at the molecular level. We developed urethane (ethyl carbamate) induced lung tumor mice model to understand the mechanism and molecules involved in the cancer genesis. There might be many molecules involved, but we subsequently emphasized here the study of alternation in the expression of NF-κB, Stat3, and inflammatory cytokines interleukin-1β and interleukin-6 to hypothesize that the microenvironment created by these molecules is promoting tumor formation. Materials and Methods: 7-8 week old Balb/c mice of either sex were given intraperitoneal (i.p.) injection of urethane (1g/kgbw) for eight consecutive weeks. Histopathological analysis was done to detect abnormality or invasions occurred in the lung tissues. Automated cell counter was used to count the number of inflammatory cells. The expression of NF-κB, Stat3, and IL-1β was observed at translational level by western blot, while the expression of IL-1β and IL-6 was observed at transcriptional level by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) method. Secretion of IL-1β and IL-6 in the blood was measured by enzyme-linked immunosorbent assay (ELISA) method at different time intervals. Results: Histopathological analysis showed various lung cancer stages hyperplasia, atypical adenomatous hyperplasia, and adenocarcinoma. Increased population of inflammatory cells, persistant expression of NF-κB, Stat3, pStat3, and IL-1β at translational level, while at transcriptional level constitutive enhanced expression of IL-1β and IL-6 followed by increased secretion of IL-1β and IL-6 in the blood were observed in urethane-injected mice in comparison to phosphate buffer saline (PBS) injected mice at 12, 24, and 36 weeks. Conclusions: Overexpression of key molecules such as NF-κB, Stat3, pStat3, IL-1β, and IL-6 might have caused chronic inflammation, leading to the progression of lung cancer.
Cooperative catalysis by polymetallic copper-zinc complexes in the efficient oxidation of alcohols under solvent free condition
(Elsevier, 2014) Rosmita Borthakur; Mrityunjaya Asthana; Arvind Kumar; Ram A. Lal
The oxidation of alcohols to corresponding aldehydes and ketones has been achieved using polymetallic complexes as catalyst with hydrogen peroxide as the terminal oxidant under a solvent free condition. These polymetallic complexes linked to a single ligand system exhibited remarkable cooperative effect in the oxidation process. This ecologically friendly procedure releases water as the only by-product. © 2014 Elsevier B.V. All rights reserved.
Copper pretreatment augments ultraviolet B toxicity in the cyanobacterium Anabaena doliolum: A proteomic analysis of cell death
(2008) Poonam Bhargava; Arvind Kumar; Yogesh Mishra; Lal Chand Rai
This study provides first-hand proteomic characterisation of Cu-pretreatment-induced augmentation of ultraviolet B toxicity in the cyanobacterium Anabaena doliolum Bharadwaja. Of the three treatments (i.e. Cu, UV-B and Cu:+:UV-B) tested, the UV-B treatment of Cu-pretreated Anabaena produced a greater inhibition of oxygen evolution, 14C fixation, ATP and NADPH contents than UV-B alone. Proteomic analysis using two-dimensional gel electrophoresis (2DE), MALDI-TOF MS/MS and reverse transcription polymerase chain reaction (RT-PCR) of Cu, UV-B, and Cu:+:UV-B treated Anabaena exhibited significant and reproducible alterations in 12 proteins. Of these, manganese superoxide dismutase (Mn-SOD), iron superoxide dismutase (Fe-SOD) and peroxiredoxin (PER) are antioxidative enzymes; ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo), phosphoribulokinase (PRK), flavodoxin (Flv), plastocyanin (PLC), phosphoglycerate kinase (PGK), phycocyanin (PC) and phycoerythrocyanin α-chain (PC α-chain) are linked with photosynthesis and respiration; and DnaK and nucleoside diphosphate kinase (NDPK) are associated with cellular processes and light signalling, respectively. However, when subjected to a high dose of UV-B, Cu-pretreated Anabaena depicted a severe down-regulation of DnaK, NDPK and Flv, probably because of inevitable oxidative stress. Thus, the augmentation of UV-B toxicity by Cu can be attributed to the down-regulation of DnaK, NDPK and Flv. © CSIRO 2008.