Namita Singh - Academia.edu (original) (raw)

Papers by Namita Singh

Circulation Research, 2000

Molecular Biology and Evolution

Host-dependency factors have increasingly been targeted to minimize antiviral drug resistance. In... more Host-dependency factors have increasingly been targeted to minimize antiviral drug resistance. In this study, we have demonstrated that inhibition of p38 mitogen-activated protein kinase (a cellular protein) suppresses buffalopox virus (BPXV) protein synthesis by targeting p38-MNK1-eIF4E signaling pathway. In order to provide insights into the evolution of drug resistance, we selected resistant mutants by long-term sequential passages (P; n = 60) in the presence of p38 inhibitor (SB239063). The P60-SB239063 virus exhibited significant resistance to SB239063 as compared to the P60-Control virus. To provide mechanistic insights on the acquisition of resistance by BPXV-P60-SB239063, we generated p38-α and p38-ϒ (isoforms of p38) knockout Vero cells by CRISPR/Cas9-mediated genome editing. It was demonstrated that unlike the wild type (WT) virus which is dependent on p38-α isoform, the resistant virus (BPXV-P60-SB239063) switches over to use p38-ϒ so as to efficiently replicate in the ta...

Journal of Food Processing & Technology, 2013

Milk and milk products comprise essential nutrients for all age groups. Hence ensuring the qualit... more Milk and milk products comprise essential nutrients for all age groups. Hence ensuring the quality and safety of dairy products offered to the consumers is mandatory objective of the dairy industry. Bacterial spores one of the hardiest forms of life can be exploited as biosensing element over the cell based detection system because of longer shelf life of the spores. Bacterial spores in the presence of favorable conditions germinate into metabolically active vegetative cells. The ability of spores to carry out cycle between the spore state and germinated cell contributes to their attractiveness as biosensing systems. The presence of contaminants such as antibiotics, aflatoxin and bacteria affects the life cycle events of bacterial spores and hence can be exploited as platform for detection of aforementioned in milk. This review focuses on the application of bacterial spores as biosensing system for contaminants in milk system. Furthermore, we have focused our attention on the discussion of principal concepts of spore structure and spore germination and examples of spore based detection systems that have been achieved up until now to detect potential contaminants in milk in our laboratory.

Food Chemistry, 2009

Epidemiological studies have consistently linked abundant consumption of fruits and vegetables to... more Epidemiological studies have consistently linked abundant consumption of fruits and vegetables to a reduction of the risk of developing several types of cancer. In most cases, however, the identification of specific fruits and vegetables that are responsible for these effects is still lacking, retarding the implementation of effective dietary-based chemopreventive approaches. As a first step towards the identification of foods endowed with the most potent chemopreventive activities, we evaluated the inhibitory effects of extracts isolated from 34 vegetables on the proliferation of 8 different tumour cell lines. The extracts from cruciferous vegetables as well as those from vegetables of the genus Allium inhibited the proliferation of all tested cancer cell lines whereas extracts from vegetables most commonly consumed in Western countries were much less effective. The antiproliferative effect of vegetables was specific to cells of cancerous origin and was found to be largely independent of their antioxidant properties. These results thus indicate that vegetables have very different inhibitory activities towards cancer cells and that the inclusion of cruciferous and Allium vegetables in the diet is essential for effective dietary-based chemopreventive strategies.

Detection and elimination of Bacillus spp. spores is a challenging task being faced by food indus... more Detection and elimination of Bacillus spp. spores is a challenging task being faced by food industry and human life. Spore eradication techniques such as U.V., heat and other stress treatments fails due to dormant and robust nature of spores. Exposure of spores to specific germinants trigger germination and vegetative cells are formed which are metabolically very active and fragile so can be easily eliminated from the site. Mechanistic details for the initiation and specificity of Bacillus spores towards germinants are required. A rapid, simple and inexpensive technique based on fluorescent labeling has been developed for detection of onset and specificity of germination in B. megaterium spores. This technique requires heating the spore suspension followed by addition of germinant and treating it with fluorescent dye diacetate fluorescein which is cell viability stain and is cleaved effectively by germinating spores as compared to dormant spores. Image analysis with EMCCD allows for automated data processing for dormant and germinating spores. A typical increase in fluorescence was observed when spores were germinated with D-Dextrose within minutes. There is a high level of specificity being expressed by spores towards germinants as revealed by their respective florescence pattern.

Superoxide dismutase (SOD), the antioxidant enzyme exists in four diverse forms in cyanobacteria ... more Superoxide dismutase (SOD), the antioxidant enzyme exists in four diverse forms in cyanobacteria i.e. FeSOD, MnSOD, Cu/ZnSOD and NiSOD. FeSOD has an ancestral origin from the GSB ancestor of PSI while MnSOD has protobacterial ancestor to PSII & mitochondria. Cu/ZnSOD shows lateral gene transfer while NiSOD is rarely found. Fe & Mn forms share similarity while Cu/Zn form does not. SOD is prevalent in all subcellular locations where O 2-(superoxide) radicals are formed. SOD plays a defensive role at the time of environmental stress like chilling, dessication, light stress, metatoxicity etc and its activity is usually seen higher at the time of stress. Inactivation of SOD gene results in oxidative damage to the cell.

Emergence of microbial resistance is the one of the major problem nowadays; thus there have been ... more Emergence of microbial resistance is the one of the major problem nowadays; thus there have been tremendous efforts towards finding new metabolites for the development of new antimicrobial drugs. Cyanobacteria have been identified as one of the most promising group of microorganisms from which novel and biochemically active natural products can be isolated. Synthesis of nanoparticles using plant extracts has gained utmost importance in research world but biosynthesis of nanoparticles using microbes is still unexplored and underexploited. In the case of micro-algal species, Cyanobacteria have been studied in great detail for in-vitro silver nano-particle generation and stabilization. Treatment of Cyanobacterial cell extracts with silver nitrate solution in proper concentration and conditions may cap the microbial metabolic proteins and may cause the reduction of silver ions leading to synthesis of silver nanoparticles. In the present study, chemically synthesized silver nanoparticles...

To investigate the production of cellulases from Aspergillus heteromorphus, submerged fermentatio... more To investigate the production of cellulases from Aspergillus heteromorphus, submerged fermentation was performed using wheat straw as substrate. Optimization of saccharification conditions like pH, temperature and time were studied. Highest reducing sugar was released on 5th day at 5 pH, 30° C temperature. When A. heteromorphous was grown on wheat straw in submerged fermentation after 5 days incubation at 30 ° C, 3.2 IU/ml and 83 IU/ml, filter paper activity and CMCase activity respectively.

Phytotherapy Research

The radio source Sagittarius A * (Sgr A *) is believed to be a hot, inhomogeneous, magnetized pla... more The radio source Sagittarius A * (Sgr A *) is believed to be a hot, inhomogeneous, magnetized plasma flowing near the event horizon of the 3.6 × 10 6 M ⊙ black hole at the galactic center. At a distance of 8kpc (≃ 2.5 × 10 22 cm) the black hole would be among the largest black holes as judged by angular size. Recent observations are consistent with the idea that the millimeter and submillimeter photons are dominated by optically thin, thermal synchrotron emission. Anticipating future Very Long Baseline Interferometry (VLBI) observations of Sgr A * at these wavelengths, we present here the first dynamically self-consistent models of millimeter and sub-millimeter emission from Sgr A * based on general relativistic numerical simulations of the accretion flow. Angle-dependent spectra are calculated assuming a thermal distribution of electrons at the baryonic temperature dictated by the simulation and the accretion rate, which acts as a free parameter in our model. The effects of varying model parameters (black hole spin and inclination of the spin to the line of sight) and source variability on the spectrum are shown. We find that the accretion rate value needed to match our calculated millimeter flux to the observed flux is consistent with constraints on the accretion rate inferred from detections of the rotation measure. We also describe the relativistic jet that is launched along the black hole spin axis by the accretion disk and evolves to scales of ∼ 10 3 GM c −2 , where M is the mass of the black hole.

Processes

The objective of this paper is to establish the significance of the mycoremediation of contaminan... more The objective of this paper is to establish the significance of the mycoremediation of contaminants such as Cd2+ to achieve sustainable and eco-friendly remediation methods. Industries such as electroplating, paint, leather tanning, etc. release an enormous amount of Cd2+ in wastewater, which can drastically affect our flora and fauna. Herein, we report on the in vitro bioadsorption of Cd2+ ions using fungal isolates obtained from different contaminated industrial sites. The detailed studies revealed that two fungal species, i.e., Trichoderma fasciculatum and Trichoderma longibrachiatum, were found to be most effective against the removal of Cd2+ when screened for Cd2+ tolerance on potato dextrose agar (PDA) in different concentrations. Detailed adsorption studies were conducted by exploring various experimental factors such as incubation time, temperature, pH, inoculum size, and Cd2+ salt concentrations. Based on optimum experimental conditions, T. fasciculatum exhibited approximat...

Journal of Fungi

Aflatoxin-affected groundnut or peanut presents a major global health issue to both commercial an... more Aflatoxin-affected groundnut or peanut presents a major global health issue to both commercial and subsistence farming. Therefore, understanding the genetic and molecular mechanisms associated with resistance to aflatoxin production during host–pathogen interactions is crucial for breeding groundnut cultivars with minimal level of aflatoxin contamination. Here, we performed gene expression profiling to better understand the mechanisms involved in reduction and prevention of aflatoxin contamination resulting from Aspergillus flavus infection in groundnut seeds. RNA sequencing (RNA-Seq) of 16 samples from different time points during infection (24 h, 48 h, 72 h and the 7th day after inoculation) in U 4-7-5 (resistant) and JL 24 (susceptible) genotypes yielded 840.5 million raw reads with an average of 52.5 million reads per sample. A total of 1779 unique differentially expressed genes (DEGs) were identified. Furthermore, comprehensive analysis revealed several pathways, such as diseas...

Bioeconomy [Working Title]

Cellulase is an enzyme which depolymerizes the cellulose into glucose. Cellulases are produced by... more Cellulase is an enzyme which depolymerizes the cellulose into glucose. Cellulases are produced by a diverse array of microbes including fungi, bacteria, yeast and actinomycetes. Considerable research for understanding the mechanism of cellulases began in early 1950s because of the significant use of these enzymes in various industries. This review provides a general account structure and availability of lignocellulosic biomass, pretreatment strategies for effective digestion, cellulase producing organisms, cellulase activity assay, and enzymology of cellulose degradation. Cellulase production, optimization, purification and characterization studies in addition to the industrial application of cellulase have also been discussed. At last a brief account of present market scenario of cellulases and future prospects of the study are also taken into account.

Polycyclic Aromatic Compounds

Abstract The aim of the research is the dissipation of Phenanthrene in sodic soil in the presence... more Abstract The aim of the research is the dissipation of Phenanthrene in sodic soil in the presence of PGPR by two mucilagenous plant species (Trigonella foenum-graceum and Brassica juncea). To evaluate of affectivity of bioremediation in the presence of local sodic soil was artificially contaminated with the known different concentration of Phenanthrene separately to analyze the dissipation of Phenanthrene. Soil samples were taken after the 30 days of incubation in the presence of plant species and PGPR. Gas Chromatography result clearly indicate that Trigonella foenum-graceum (99%) is more efficient plant over the Brassica juncea (96%) is further indicate that PGPR having synergistic effect on phytoremediation of Phenanthrene. Highlights Trigonella foenum-graceum is more efficient plant species over the Brassica juncea to dissipate Phenanthrene contaminated sodic soil. PGPR play synergistic effect on phytoremediation.

Archives of Microbiology

Awareness of the consumer has increased the demand of safe and chemical-free foods, and consequen... more Awareness of the consumer has increased the demand of safe and chemical-free foods, and consequently it has increased the demand of antibacterial bioactive compounds. In the present study, antibacterial compound produced by a local bacterial isolate NSD MTCC 10072, showing antagonistic activity against six human pathogens, was isolated, partially purified and characterized. Maximum production of antibacterial compound was observed between 51 and 60 h after seeding. The antibacterial activity of the compound was found to be thermostable up to 80 °C for 60 min and its efficacy was very good between pH 4 and 12. Minimum inhibitory concentration (25.84 µg/µl) of the antibacterial compound was observed against Streptococcus aureus NICM 2901. GC–MS analysis of the bacterium secreted chemical compound (C11H18N2O2) was used to identify the antimicrobial compound as Pyrrolo(1,2-a) pyrazine-1,4-dione, hexahydro-3-(2-methylpropyl). In Silico studies showed that the antimicrobial compound is non-toxic, non-irritating and followed Lipinski-type properties which suggested that the compound could be used as potential drug against different human pathogens.

Scientific reports, Jan 31, 2017

We performed integrative analysis of genes associated with type 2 Diabetes Mellitus (T2DM) associ... more We performed integrative analysis of genes associated with type 2 Diabetes Mellitus (T2DM) associated complications by automated text mining with manual curation and also gene expression analysis from Gene Expression Omnibus. They were analysed for pathogenic or protective role, trends, interaction with risk factors, Gene Ontology enrichment and tissue wise differential expression. The database T2DiACoD houses 650 genes, and 34 microRNAs associated with T2DM complications. Seven genes AGER, TNFRSF11B, CRK, PON1, ADIPOQ, CRP and NOS3 are associated with all 5 complications. Several genes are studied in multiple years in all complications with high proportion in cardiovascular (75.8%) and atherosclerosis (51.3%). T2DM Patients' skeletal muscle tissues showed high fold change in differentially expressed genes. Among the differentially expressed genes, VEGFA is associated with several complications of T2DM. A few genes ACE2, ADCYAP1, HDAC4, NCF1, NFE2L2, OSM, SMAD1, TGFB1, BDNF, SYV...

Recent Patents on Biotechnology, 2017

Heavy metals are natural constituents of the earth&amp;#39;s crust, but some heavy metals... more Heavy metals are natural constituents of the earth&amp;#39;s crust, but some heavy metals like cadmium, lead, mercury, arsenic etc. are injurious to living organisms at higher concentration. Nowadays, anthropogenic activities have altered geochemical cycles and biochemical balance of heavy metals. Biomolecules are used nowadays for removal of heavy metals compared to other synthetic biosorbents due to their environmental friendly nature and cost effectiveness. The goal of this work is to review research work and patents related to adsorption through biomolecules like polysaccharides, polypeptides, lignin etc. and bio-sorption by biological material that are used for heavy metal removal. Biomolecules are cost effective and there have been significant progresses in the remediation of heavy metals but, still there are some problems that need to be rectified for its application at industrial processes.

Asian Journal of Home Science, 2009

The percentage of moderate workers was low, constituting 19.65% of the total study subjects. Howe... more The percentage of moderate workers was low, constituting 19.65% of the total study subjects. However, more than one-third (37.06 %) of women in the study area were heavy workers. The percentage of women spending <1700 Kcal per day was 15.2%. The mean energy expenditure was found to be 2326.5 Kcal per day. The vast majority of tribal women (84.6%) had energy expenditure more than their energy intake. The mean energy balance of the tribal women in the study area was 683.4 Kcal/day. Majority of study subjects (84.3 %) had negative energy balance and only 15.6% had positive energy balance. Nearly 58.2% women had energy balance as low as less than-500 Kcal per day. The mean energy balance was highest (200.79 kcal) among sedentary worker, followed by moderate worker (-583.91 kcals) and heavy worker (-1299.80 kcals). The maximum negative energy balance (-1299.80 kcal) was found in heavy worker group, though they were taking 54.96% of estimated mean RDA which was higher than the 51.86 % of estimated mean RDA, taken by sedentary worker. The negative energy balance among moderate worker group was only-583.91 kcal.

Gastroenterology & hepatology, 2015

Therapeutic drug monitoring (TDM) is the clinical practice of measuring drug concentrations or me... more Therapeutic drug monitoring (TDM) is the clinical practice of measuring drug concentrations or metabolites to attain a targeted concentration in a patient's bloodstream, thereby optimizing individual dosage regimens. With the well-established knowledge of the relationship of the genetic variability of thio-purine metabolism driven by the thiopurine S-methyltransferase pathway, and the recent data supporting pharmacokinetic variability and immunogenicity with anti-tumor necrosis factor (anti-TNF) therapies, TDM has emerged as a necessary mechanism to enhance drug efficacy. This article reviews data describing the relationship between drug concentrations and outcomes, including the achievement of a sustained and durable remission. The effect of antidrug antibodies on drug efficacy and toxicity is also examined. Furthermore, we describe different assays that are used for measuring these drug and antibody concentrations, including the advantages and pitfalls of these tools. An algor...

Asian Journal of Experimental Sciences, 2009

F1000Research, 2015

In prokaryotes, horizontal gene transfer (HGT) has been regarded as an important evolutionary dri... more In prokaryotes, horizontal gene transfer (HGT) has been regarded as an important evolutionary drive to acquire and retain beneficial genes for their survival in diverse ecologies. However, in eukaryotes, the functional role of HGTs remains questionable, although current genomic tools are providing increased evidence of acquisition of novel traits within non-mating metazoan species. Here, we provide another transcriptomic evidence for the acquisition of massive plant genes in the mosquito, Anopheles culicifacies. Our multiple experimental validations including genomic PCR, RT-PCR, real-time PCR, immuno-blotting and immuno-florescence microscopy, confirmed that plant like transcripts (PLTs) are of mosquito origin and may encode functional proteins. A comprehensive molecular analysis of the PLTs and ongoing metagenomic analysis of salivary microbiome provide initial clues that mosquitoes may have survival benefits through the acquisition of nuclear as well as chloroplast encoded plant ...