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KUMAR, M.

Publications and source records attributed to KUMAR, M..

3 recordsLinked to original sources

ConsensusMetaDA: an R Package for consensus-based differential abundance analysis of metagenomic data.

Differential abundance (DA) analysis is critical in metagenomics research for identifying microbial taxa associated with variable biological conditions. Despite numerous mature DA tools being available, they often generate disparate results, making it challenging to obtain consistent and biologically meaningful findings. Tools differ substantially in their input requirements, underlying statistical models, and filtering strategies, yet researchers typically rely on a single tool due to the practical challenges of integrating multiple algorithms with variable workflows and non-standardized output formats. To address this challenge, we developed ConsensusMetaDA, an easy-to-use R package that integrates five widely-used DA tools (ALDEx2, DESeq2, EdgeR, metagenomeSeq, and ADAPT) into a streamlined three-function workflow. The package generates unified output reports and comprehensive visualizations including rarefaction curves, alpha/beta diversity analyses, taxonomic abundance plots, and Venn/UpSet diagrams to visualize algorithmic consensus and disagreement. We benchmarked ConsensusMetaDA on well-characterized public datasets and simulated data, demonstrating that individual tools exhibit complementary strengths and weaknesses. On datasets with known null results, EdgeR and DESeq2 reported false positive differentially abundant OTUs while ALDEx2, metagenomeSeq, and ADAPT correctly identified none. Conversely, simulations revealed that ALDEx2, metagenomeSeq, and ADAPT frequently missed true positives that EdgeR and DESeq2 detected. Our consensus approach improves both sensitivity and specificity compared to any single tool and enables researchers to minimize either false positive or false negative rates based on study-specific priorities. ConsensusMetaDA is freely available with comprehensive documentation at: https://github.com/FieldLabFNQOmics/ConsensusMetaDA

bioinformatics↗

Isolation, characterization and antibiogram of Bacillus cereus from milk products

This study, conducted within the Department of Veterinary Public Health and Epidemiology (VPHE) at Lala Lajpat Rai University of Veterinary and Animal Sciences (LUVAS), undertook a comprehensive investigation into the prevalence, identification, characterization, and antibiotic resistance patterns of Bacillus cereus in milk products from various regions of Haryana, India. Using a systematic sampling strategy, eight tehsils spanning two agroclimatic zones were selected for sample collection. A total of 200 samples were obtained from randomly selected shops within these tehsils. Each sample underwent pre-enrichment in Brain Heart Infusion (BHI) broth with a 1:10 dilution to facilitate the growth of any existing B. cereus contaminants. Following pre-enrichment, streaking on selective PEMBA agar plates was performed for the isolation of B. cereus colonies. The presence of presumptive B. cereus colonies was confirmed through a series of biochemical tests, including gram staining, nitrate reduction, oxidase, indole, methyl red reduction, Voges Praskaur, and catalase tests. Molecular analysis using the 16SrRNA gene confirmed the presence of 88 positive B. cereus isolates. Further characterization involved the differentiation of B. cereus from Bacillus thuringiensis via the cry2 gene. Additionally, the study assessed the presence of virulence-associated genes, identifying gyrB, cytk, hblA, and nheA genes in the isolated strains. Geographical variation in B. cereus prevalence was observed, with higher rates detected in certain tehsils such as Kalka (68%) and Panchkula (60%). Antibiotic sensitivity testing using Tryptone Soya Agar (TSA) broth for enrichment and Muller Hinton Agar (MHA) plates with 14 antibiotic discs revealed widespread resistance among the isolates. Notably, all isolates exhibited resistance to Ampicillin, Cefazolin, Methicillin, Polymyxin-B, and Penicillin, while displaying maximum sensitivity to Amikacin, Gentamycin, Levofloxacin, and Meropenem. Alarmingly, all isolates displayed multiple drug resistance (MDR), indicating resistance to three or more classes of antibiotics. These findings underscore the urgent need for stringent food safety measures and surveillance protocols in dairy production and distribution. Effective interventions are imperative to mitigate the risk of B. cereus contamination and combat antibiotic resistance in milk products. Collaboration with the VPHE department at LUVAS and continued research efforts are essential to address emerging challenges and uphold food safety standards effectively.

molecular biology↗

Quinacrine binds to the kinase domain of FGFR1 and inhibits its activity

BackgroundFGF family receptors, especially FGFR1, have been widely implicated for their potential role in the promotion of oncogenesis and chemoresistance in lung cancer. Quinacrine, an anti-malarial drug, has been widely reported to exhibit anti-neoplastic properties through the activation of p53 and simultaneous inhibition of NF-kB signaling pathways in cancer cells. MethodsThe binding of QC to FGFR1 was studied using molecular docking and molecular dynamics simulation studies. The experimental kinase activity assay for the protein was performed using a luminescence-based kinase assay. FGF-induced phosphorylation and proliferation were studied by cell counting and western blotting. Matrigel-based cell migration was conducted to assess migration activity. ResultsQC interacted with multiple residues around the kinase insert domain of FGFR1 through hydrogen bonding, hydrophobic interactions, and water bridges. The kinase activity inhibition assay demonstrated a significant reduction in FGFR1 kinase activity by QC at higher concentrations, which was further observed at the cellular level in inhibition of FGFR1 phosphorylation and proliferation by QC at higher exposure concentrations of FGF stimulated cells. These effects were further validated downstream in the FGF-induced activation of cell migration. ConclusionQC did form a stable interaction with residues of FGFR1 at another allosteric site surrounding the kinase domain, leading to inhibition of its kinase activity at higher drug concentrations. This effect was further observed at the cellular level in both acidic and basic FGF ligand-induced proliferation, phosphorylation of FGFR1, and cell migration, where a trend of significant reduction in activity was observed at higher drug concentrations.

cancer biology↗