Browsing by Author "Richa Rai"

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Annual and seasonal variations in tropospheric ozone concentrations around Varanasi
(Taylor and Francis Ltd., 2008) Supriya Tiwari; Richa Rai; Madhoolika Agrawal
This study examines the annual, seasonal and diurnal variations in the ambient concentrations of ozone at a suburban site of Varanasi, India, during 2002-2006. Prominent seasonal variations in ozone concentrations were recorded. Ozone concentrations were higher during the warmer months. Daytime 12-hourly mean monthly ozone concentrations varied from 45.18 to 62.35 ppb during summer, from 28.55 to 44.25 ppb during winter and from 24 to 43.85 ppb during the rainy season from 2002 to 2006. Distinct diurnal variations in ozone concentrations were also observed. Daytime maxima in ozone concentration were recorded between 1200 and 1400 h, whereas morning and evening hours showed lower concentrations of ozone. Ozone concentrations in the atmosphere depended on several meteorological factors. Monthly average ozone concentration was significantly correlated with maximum temperature (p<0.001) and mean monthly temperature (p<0.05), maximum relative humidity (p<0.001), minimum relative humidity (p<0.001) and mean monthly relative humidity (p<0.001), and sunshine hours (p<0.001). Ozone concentrations in the ambient air have shown an increase in the past decade that was more in the winter and rainy seasons than in the summer. This study suggests that ozone concentrations around Varanasi were sufficiently high to cause significant damage to agricultural production. The present work can be extended to a regional level by incorporating modelling studies using recent remote sensing tools.
Application of ethylene diurea (EDU) in assessing the response of a tropical soybean cultivar to ambient O3: Nitrogen metabolism, antioxidants, reproductive development and yield
(Academic Press, 2015) Richa Rai; Madhoolika Agrawal; Krishna Kumar Choudhary; S.B. Agrawal; Lisa Emberson; Patrick Büker
The present study deals with assessment of response of a tropical soybean cultivar to O3 in relation to photosynthetic pigments, chlorophyll fluorescence kinetics, antioxidative capacity, N assimilation enzymes, metabolites, growth and yield using ethylene diurea (EDU) given as a soil drench (400) ppm at an interval of 10 days after germination up to maturity. Mean O3 concentration was 42ppb and accumulated threshold above 40ppb (AOT 40) was 9.07ppmh. Lipid peroxidation and total phenolics reduced, while increases in activities of antioxidative and nitrogen assimilation enzymes, ascorbic acid, protein, photosynthetic pigments, Fv/Fm ratio, number of leaves, flowers, pods, branches and yield attributes were found in EDU treated plants. EDU alleviated the negative effects of O3 by enhancing the first line of defense against ROS and protecting N assimilation enzymes at flowering and maintaining adequate supply of photosynthates to developing pods during pod filling stage. EDU provided maximum protection between flowering to pod filling stage. © 2014 Elsevier Inc.
Assessment of competitive ability of two Indian wheat cultivars under ambient O3 at different developmental stages
(2014) Richa Rai; Madhoolika Agrawal
The concentrations of O3 are increasing, which may have potential adverse effects on crop yield. This paper deals with assessing the intraspecific variability of two wheat cultivars (PBW 343 and M 533) at different growth stages using open top chambers. Mean O3 concentrations were 50.2 and 53.2 ppb, and AOT40 values were 9 and 12.1 ppm h, respectively, in 2008-2009 and 2009-2010. Reproductive stage showed higher AOT40 values (6.9 and 9.2 ppm h) compared to vegetative (2.23 and 2.9 ppm h). Critical levels of a 3-month AOT 40 of 3 ppm h led to 6 % yield reduction in two wheat cultivars for two consecutive years. Variations in photosynthesis rate, stomatal conductance (gs), Fv/Fm ratio, photosynthetic pigments, primary and secondary metabolites, morphological parameters, and yield attributes were measured at vegetative and reproductive stages. Reductions in number of leaves, leaf area, total biomass, root/shoot ratio, RGR, photosynthetic pigments, protein content, and Fv/Fm ratio in PBW 343 were more than M 533 at reproductive stage. Photosynthetic rate did not vary between the cultivars, but gs was higher in PBW 343 compared to M 533 under ambient O3. Higher total phenolics and peroxidase activity were recorded in M 533 at reproductive stage conferring higher resistance at latter age. Results of O3 resistance showed that M 533 was sensitive compared to PBW 343 during vegetative stage but developed more resistance at reproductive stage. PBW 343 with larger leaf area and high gs is more sensitive than M 533 with smaller leaf area and low gs. The study suggests that the sensitivity varied with plant growth stage, and the plant showing higher sensitivity during vegetative period developed more resistance during reproductive period due to higher defense mechanism. Though the yield reductions were same in both cultivars under ambient O3, the mechanism of acquiring the resistance is different between the cultivars. © 2013 Springer-Verlag Berlin Heidelberg.
Change in refractive index of p-SnS thin film due to molecular polarizability
(SPIE, 2024) Vinita; P. Arun; Chandra Kumar; Richa Rai; Bhartendu Kumar Singh
The present investigation describes the optical properties of tin sulfide (SnS) thin films that were deposited on fluorine-doped tin oxide (FTO)-coated glass substrates at room temperature using the thermal evaporation method. The obtained films showed oriented growth with "p"-type conductivity. The effect of film thickness on the optical behavior of FTO/SnS was analyzed and compared with data from SnS films grown on glass and indium tin oxide substrates. Our study indicates that the properties of SnS film are independent of the substrate material. The optical band gap was found to decrease from 2.07 to 1.30 eV with increasing film thickness. We have seen a quantum confinement effect in samples whose grain size was less than 27 nm. The refractive indices of the samples were used to determine the single oscillator and dispersion energies using the Wemple-DiDomenico single-oscillator model. Other optical parameters were also determined using the transmission and absorption spectra. Besides grain size and number of defects, our data showed that the polarizability of the molecules along the Van der Waals direction influenced SnS optical properties. The interpretation was made possible considering the carrier concentration of free charges remained constant with varying film thickness. Such work provides insight into how to choose the appropriate thickness and, hence, grain sizes for optoelectronic applications. © 2024 Society of Photo-Optical Instrumentation Engineers (SPIE).
Decreased Pattern Recognition Receptor Signaling, Interferon-Signature, and Bactericidal/Permeability-Increasing Protein Gene Expression in Cord Blood of Term Low Birth Weight Human Newborns
(2013) Vikas Vikram Singh; Sudhir Kumar Chauhan; Richa Rai; Ashok Kumar; Shiva M. Singh; Geeta Rai
Background:Morbidity and mortality rates of low birth weight (LBW) newborns at term are higher than rates in normal birth weight (NBW) newborns. LBW newborns are at greater risk to acquire recurrent bacterial and viral infections during their first few weeks of life possibly as an outcome of compromised innate immune functions. As adaptive immunity is in a naive state, increased risk of infection of LBW as compared to NBW newborns may reflect impairments in innate immunity.Methodology:To characterize the increased susceptibility to infections in LBW newborns we used microarray technology to identify differences in gene expression in LBW newborns (n = 8) compared to NBW newborns (n = 4) using cord blood. The results obtained from the microarray study were validated on a larger number of samples using real time RT-PCR (LBW = 22, NBW = 18) and western blotting (LBW = 12, NBW = 12). The Interferome database was used to identify interferon (IFN) signature genes and ingenuity pathway analysis identified canonical pathways and biological functions associated with the differentially expressed genes in LBW newborns. ELISAs for IFNs and bactericidal/permeability-increasing protein were performed in both LBW and NBW newborns and in adults (LBW = 18, NBW = 18, Adults = 8).Principal Findings:Upon microarray analysis, we identified 1,391 differentially expressed genes, of which, 1,065 genes were down-regulated and 326 genes were up-regulated in the LBW compared to NBW newborns. Of note, 70 IFN-signature genes were found to be significantly down-regulated in LBW compared to NBW newborns. Ingenuity pathway analysis revealed pattern recognition receptors signaling including Toll-Like Receptors (TLRs) -1, -5, and -8 genes and IFN signaling as the most significantly impacted pathways. Respiratory infectious diseases were the most significantly affected bio-functions in LBW newborns.Conclusion and Significance:Diminished PRRs, IFN-signature, and BPI gene expression raises the possibility that impairments in these pathways contribute to the susceptibility of LBW term infants to infection. © 2013 Singh et al.
Decreased toll-like receptor-4/myeloid differentiation factor 88 response leads to defective interleukin-1 (3 production in term low birth weight newborns
(Lippincott Williams and Wilkins, 2014) Vikas Vikram Singh; Sudhir Kumar Chauhan; Richa Rai; Ashok Kumar; Geeta Rai
Background: Morbidity and mortality rates are very high in low birth weight (LBW) newborns because of their increased susceptibility to infections compared with normal birth weight (NBW) newborns. A case and control study was designed to identify the status of toll-like receptor-4 (TLR-4) signaling and maternally derived immunoglobulin-G (IgG) subclasses in term LBW newborns compared with NBW newborns. Methods: To understand the basis of increased susceptibility to infections in LBW newborns, the levels of pro- and antiinflammatory cytokines interleukin-1β (IL-1β) and interleukin-10 (IL-10), respectively, released in response to lipopolysaccharide (LPS) stimulation of cord blood cells of LBW (n = 20) and NBW (n = 18) newborns, were quantified by enzymelinked immunosorbent assay. Further, LPS-induced expression of TLR-4 and basal and LPS-induced expression of myeloid differentiation factor 88 (MyD88) were examined at mRNA levels in both groups. The levels of IgG subclasses in LBW (n = 20) and NBW (n = 18) newborns were quantified by enzyme-linked immunosorbent assay to explore the role of maternally derived immunity in LBW newborns. Results: LPS-mediated release of IL-1β was significantly diminished in LBW newborns when compared with NBW newborns, whereas there was no significant difference in IL-10. Decreased production of IL-1β in LBW newborns was correlated with reduced expression of TLR-4 and MyD88 mRNA. No significant differences were observed in the levels of all 4 IgG subclasses between LBW and NBW newborns. Conclusions. Decreased production of IL-1β in LBW newborns was correlated with reduced expression of TLR-4 and MyD88 mRNA. This raises the possibility of increased susceptibility to infections in LBW when compared with the NBW newborns at term. Comparable levels of IgG subclasses in the 2 groups of newborns indicate that IgG is not a limiting factor in defense against infection in LBW newborns. Copyright © 2014 by Lippincott Williams and Wilkins.
Development of Resistance in Two Wheat Cultivars Against Constant Fumigation of Ozone
(Springer, 2018) Era Singh; Richa Rai; Bhanu Pandey; Madhoolika Agrawal
Tropospheric ozone (O3) has been recognized as the major threat for worldwide agriculture and wheat production will have a crucial bearing on food security in the coming decades. The present study was conducted to evaluate the response of two wheat cultivars (HUW 234 and HP 1209) at constant levels of elevated O3 and to compare results of the present open top chamber studies (OTC) with free air concentration studies (FACE). Wheat cultivars were exposed to 70 (T1) and 100 (T2) ppb O3 for 4 h daily from germination to maturity. Both the cultivars showed differential and negative responses on photosynthetic pigments, morphological characteristics and total biomass at different stages of sampling. Photosynthetic rate, stomatal conductance and photosynthetic efficiency were negatively affected by the exposure of O3 in both the cultivars. Allocation of biomass in different components of plants was observed to be diverse amongst the cultivars under different treatments resulted into the varied responses yield attributes. Exposure of O3 causes variation in quantity as well as quality of grains of both the cultivars with higher yield reduction in HP1209. Therefore, the findings of the experiments revealed that the continuous O3 exposure developed compensatory mechanism particularly reduced stomatal conductance, altered allocation pattern managed to maintain yield against O3, hence led to less reductions in yield was recorded as compared to OTCs and FACE experiments data. © 2017, The National Academy of Sciences, India.
Differential clearance mechanisms, neutrophil extracellular trap degradation and phagocytosis, are operative in systemic lupus erythematosus patients with distinct autoantibody specificities
(Elsevier, 2015) Sudhir Kumar Chauhan; Richa Rai; Vikas Vikram Singh; Madhukar Rai; Geeta Rai
Systemic lupus erythematosus (SLE) patients are generally presented with autoantibodies against either dsDNA or RNA-associated antigens (also known as extractable nuclear antigens, ENA) or both. However, the mechanisms and processes that lead to this distinctive autoantibody profile are not well understood. Defects in clearance mechanism i.e. phagocytosis may lead to enhanced microbial and cellular debris of immunogenic potential. In addition to defective phagocytosis, impaired neutrophil extracellular trap (NET) degradation has been recently reported in SLE patients. However, the extent to which both these clearance processes (NET-degradation and phagocytosis) are operative in serologically distinguished subsets of SLE patients is not established. Therefore, in this report, we evaluated NET-degradation and phagocytosis efficiency among SLE patients with different autoantibody specificities. SLE patients were classified into three subsets based on their autoantibody profile (anti-dsDNA, anti-ENA or both) as determined by ELISA. NET-degradation by SLE and control sera was assessed by sytox orange-based fluorescence assay. Neutrophil-mediated phagocytosis in the presence of SLE and control sera was determined by flowcytometry. The segregation of SLE patients revealed significant differences in NET-degradation and phagocytosis in SLE patients with autoantibodies against dsDNA and ENA. We report that NET-degradation efficiency was significantly impaired in SLE patients with anti-dsDNA autoantibodies and not in those with anti-ENA autoantibodies. In contrast to NET-degradation, neutrophil-mediated phagocytosis was impaired in all three subsets independent of autoantibody specificity. These observations suggest that varying clearance mechanisms are operative in SLE subsets with anti-dsDNA or anti-ENA autoantibodies. The results outlined in this manuscript also suggest that sub-grouping of SLE patients could be useful in delineating the molecular and pathological processes that are often missed when SLE patients are studied as a single group. Further, it will be imperative to propose that therapies targeted at improving NET clearance can be effective in anti-dsDNA+ SLE patients. © 2015 European Federation of Immunological Societies.
Differential microRNA profile and post-transcriptional regulation exist in systemic lupus erythematosus patients with distinct autoantibody specificities
(Springer New York LLC, 2014) Sudhir Kumar Chauhan; Vikas Vikram Singh; Richa Rai; Madhukar Rai; Geeta Rai
Purpose: Systemic lupus erythematosus (SLE) patients have anti-nuclear autoantibodies directed against dsDNA and RNA-associated antigens (extractable nuclear antigens; ENA). In this study, we investigated the differences in microRNA (miRNA) expression and its biological implications in SLE patients with distinct autoantibody specificities. Methods: The SLE patients were grouped into three subsets based on the type of autoantibodies present in their sera (anti-ENA+ group with autoantibodies against ENA alone; anti-dsDNA+ group having autoantibodies against dsDNA only, and anti-ENA+dsDNA+ group having autoantibodies to both dsDNA and ENA). Global miRNA expression profiling was done for each of these three groups using TaqMan® low density miRNA arrays. Results: We report that different sets of miRNAs are dysregulated in SLE patients with different autoantibody specificities. Further, Ingenuity pathway analysis (IPA) software revealed specific biological pathways that were targeted by miRNAs dysregulated in different SLE subsets. Molecules involved in cell cycle and cytoskeleton remodeling were the prime targets of miRNAs dysregulated in anti-ENA+ patients whereas miRNAs dysregulated in anti-dsDNA+ patients were found to be implicated in multiple cytokine signaling pathways. IPA analysis of gene targets of miRNAs commonly dysregulated in all three SLE subsets identified several metabolic-, hormone-, and interferon-related pathways to be affected. Conclusion: The differential miRNA expression in patients with distinct autoantibodies is suggestive of different regulatory mechanisms operating among them. Based on these observations, we are hopeful that this 'sub-grouping' approach could be used to identify other defective processes associated with varying disease manifestations in SLE and may be considered when designing therapeutic interventions. © 2014 Springer Science+Business Media.
Differential response of dwarf and tall tropical wheat cultivars to elevated ozone with and without carbon dioxide enrichment: Growth, yield and grain quality
(2013) Amit Kumar Mishra; Richa Rai; S.B. Agrawal
In past few years, atmospheric concentrations of carbon dioxide (CO2) and tropospheric ozone (O3) have increased due to anthropogenic activities. CO2 enhances the plant growth and surface level of O3 is a well-known phyto-toxic pollutant. Present study was conducted to assess the impact of elevated levels of CO2 and O3, singly and in combination on two wheat cultivars HUW-37 and K-9107 on their growth, yield attributes and grain quality in open top chambers (OTCs). Wheat plants under elevated CO2 (EC) showed increment in growth parameters while exposure to elevated O3 (EO) showed an opposite trend than EC. In elevated CO2+O3 (ECO) exposure, elevated CO2 fully protected wheat cultivars against negative effects of O3. Yield parameters showed significant increase in EC followed by ECO and in EO, significant reductions in yield were noticed in both the cultivars. Protein and total free amino-acids decreased in grains of EC, ECO and EO in both the test cultivars. Total soluble sugars and starch contents in grains increased due to EC and ECO and decreased in EO, however reducing sugars showed an opposite trend in both the cultivars. The yield data obtained from the experiment showed cultivar specific response as cultivar HUW-37 proved to be sensitive as compared to K-9107 against ambient and elevated levels of O3. The study also concludes that elevated CO2 nullified the negative impact of elevated O3 in both the test cultivars of wheat. © 2013 Elsevier B.V.
Distinct autoantibody profiles in systemic lupus erythematosus patients are selectively associated with TLR7 and TLR9 upregulation
(2013) Sudhir Kumar Chauhan; Vikas Vikram Singh; Richa Rai; Madhukar Rai; Geeta Rai
Purpose: Systemic lupus erythematosus (SLE) patients have a wide array of autoantibodies against nuclear antigens. The two predominant classes of these autoantibodies are directed either against dsDNA or RNA-associated antigens (extractable nuclear antigens; ENA). Nucleic-acid sensing Toll-like receptors (TLRs) that recognize dsDNA and RNA, have been well implicated in some murine models of SLE. We took up this study to identify if unique TLR expression patterns are associated with distinct autoantibody profiles in SLE. Methods: We segregated the patients into three subsets distinguished on the basis of autoantibody response either against dsDNA or ENA or both. We determined the mRNA expression of TLR3, 7, 8, and 9 by real-time reverse-transcription PCR in peripheral blood leucocytes (PBLs) of the SLE patients of all three subsets. TLR7 and 9 protein expression was determined by western blotting in PBLs and by flow cytometry on B-cells and monocytes. The serum interferon-alpha (IFN-α) and anti-dsDNA/-ENA autoantibodies were detected using enzyme-linked immunosorbant assay. Results: We report differential and unique TLR expression patterns associated with different autoantibody profiles. The presence of anti-ENA and anti-dsDNA autoantibodies in SLE patients was associated with elevated levels of TLR7 and TLR9 respectively. The TLR9 mRNA expression was further augmented in SLE patients with Glomerulonephritis. Interestingly, anti-dsDNA+ ENA+ patients displayed higher serum IFN-α and interferon regulatory factor 7 mRNA expression than patients with either anti-dsDNA or anti-ENA autoantibodies alone. Conclusion: Characteristic TLRs expression profile associated with distinct autoantibody repertoire is suggestive of differential immuno-regulatory pathways operative in different subsets of SLE patients. © 2013 Springer Science+Business Media New York.
DNA cleavage activity and cytotoxicity of mononuclear and trinuclear Cu(II) complexes containing 1H-pyrazole-3,5-dicarboxylic acid as ligand
(2013) Ashish Kumar Srivastava; Niraj Kumari; Rais Ahmad Khan; Richa Rai; Geeta Rai; Sartaj Tabassum; Lallan Mishra
UV-vis titrations of complexes [Cu(H2pdc)2(H 2O)2] (1) and [Cu3(pdc)2(bpy) 2(H2O)4] (2) (H3pdc=1H-pyrazole-3,5- dicarboxylic acid, bpy=2,2' bipyridine) with calf thymus DNA demonstrate their moderate binding with DNA. Fluorescence titrations show significant displacement of ethidium bromide bound to DNA by the complexes. Agarose gel electrophoretic mobility assay indicates that the complexes are able to cause concentration-dependent nicking of supercoiled DNA under physiological conditions. Ligation experiments with T4 DNA ligase enzyme show that the nicked DNA cleavage products generated by complexes (1) and (2) is religated to a large extent in the presence of T4 ligase enzyme. Complex (2) shows potential cytotoxicity against CaSki cervical cancer, HL-60 leukemic cell lines and THP-1 human monocytic cell lines with IC50 value of 1.5 μM, 2.5 μM and 10 μM respectively. A redox inactive Zn(II) complex of type [Zn(H 2pdc)2(H2O)2]· H2O (3) was also synthesized and characterized but owing to its poor solubility, further studies could not be carried out.
Evaluation of physiological and biochemical responses of two rice (Oryza sativa L.) cultivars to ambient air pollution using open top chambers at a rural site in India
(2008) Richa Rai; Madhoolika Agrawal
Air pollutant concentrations are rising in India, causing potential threats to crop production. As air pollutants are known to interfere with physiological processes, this study was conducted to assess the relative responses of physiological and biochemical characteristics of two cultivars of rice (Oryza sativa L. cv. Saurabh 950 and NDR 97) leading to variable yield responses. Twelve hour monitoring of ambient concentrations of SO2, NO2 and O3 in filtered chambers (FCs), non-filtered chambers (NFCs) and open plots (OPs) showed that O3 was the main pollutant at the experimental site. Ozone concentrations often exceeded 40 ppb during anthesis but not during the vegetative growth period. Photosynthetic rate (Ps), stomatal conductance (gs) and Fv/Fm ratio, superoxide dismutase (SOD) and peroxidase (POD) activities and photosynthetic pigments, ascorbic acid, total phenolics and protein contents were assessed at different developmental stages and yield of grains were quantified. Lipid peroxidation, SOD and POD activities, ascorbic acid and total phenolics were higher, whereas Ps, gs, Fv/Fm ratio and contents of protein and photosynthetic pigment were lower in plants of NFCs as compared to FCs. Yield decreased significantly in both cultivars grown in NFCs. NDR 97 showed less reductions in physiological characteristics, photosynthetic pigments and protein, but a greater increase in the antioxidative defense system as compared to Saurabh 950. Yield reduction was higher in NDR 97 than in Saurabh 950. This suggested that NDR 97 utilized more photosynthate in maintaining the metabolic machinery against O3 stress leading to lower translocation of photosynthate to reproductive parts. The study concluded that under natural field conditions, physiological and biochemical responses of plants varied with pollutant concentrations leading to different translocation strategies in plants, modifying their yield responses. NDR 97, a fast growing and high yielding cultivar was more sensitive than slow growing Saurabh 950. © 2008 Elsevier B.V. All rights reserved.
Evaluation of Tropospheric O3 Effects on Global Agriculture: A New Insight
(Wiley-VCH, 2012) Richa Rai; Abhijit Sarkar; S.B. Agrawal; Madhoolika Agrawal
Tropospheric ozone (O3) is now considered as the most widespread and toxic gaseous pollutant in our environment. To date, unsustainable resource utilization has turned this secondary pollutant into a major component of global climate change, and a prime threat to agricultural production. The projected levels to which O3 will increase are critically alarming, and have become a major issue of concern for global food production. Plants are "soft targets" for O3. Ozone enters plants through stomata, where it can be dissolved in the apoplastic fluid. Ozone has several potential effects on plants: direct reaction with cell membranes; generation of ROS and H2O2 (which alters cellular function by causing cell death); induction of premature senescence; and up- or down-regulation of responsive components such as genes, proteins, and metabolites. In this chapter, we make an attempt to present an overview picture of agricultural crops and O3 interactions. We summarize the vast number of available reports on plant responses to O3 at the morphological, physiological, cellular, and biochemical levels, and also address effects on crop yield, and on "-omics" level. © 2013 Wiley-VCH Verlag GmbH & Co. KGaA.
Heat shock protein 27 and its regulatory molecules express differentially in SLE patients with distinct autoantibody profiles
(Elsevier, 2015) Richa Rai; Sudhir Kumar Chauhan; Vikas Vikram Singh; Madhukar Rai; Geeta Rai
Generation of autoantigens of nuclear origin, like dsDNA and extractable nuclear antigens (ENA) have largely been associated with dysregulated apoptosis and defective clearance of apoptotic debris in SLE. Heat shock protein (HSP) 27 has been reported to have anti-apoptotic properties hence it was of interest to study the expression of HSP27 and its regulatory molecule Brn3a and hsa-miR-939 in SLE patients with distinct autoantibodies specificities. SLE patients were categorized into three subsets based on their distinct sero-positivity for either anti-dsDNA antibody alone (anti-dsDNA+ group) or anti-ENA antibody alone (anti-ENA+ group) or both (anti-dsDNA+ ENA+ group). We investigated the mRNA and protein expression of HSP27 and Brn3a in peripheral blood leukocytes (PBLs) by real-time reverse transcriptase PCR and Western blotting. Expression of apoptosis markers caspase 3 and poly (ADP-ribose) polymerase (PARP) was determined by Western blotting. Hsa-miR-939 expression was determined using TaqMan® miRNA assay. In this study, we report significant downregulation of HSP27 in anti-ENA+ patients and increased expression of caspase 3 and PARP in both anti-ENA+ and anti-dsDNA+ SLE subsets. A negative correlation was observed between the expression of HSP27 and apoptosis markers caspase 3 and PARP. Decreased Brn3a expression was observed in anti-ENA+ SLE patients, which correlated positively with HSP27 expression. Expression of hsa-miR-939, which has a potential target site for Brn3a 3' UTR, was also elevated specifically in anti-ENA+ patients. The decreased expressions of HSP27, Brn3a along with elevated levels of hsa-miR-939 are selectively associated with anti-ENA+ patients and HSP27 was observed to be inversely associated with apoptosis. These findings are suggestive of distinct regulatory processes operative in SLE patient subsets with different autoantibody specificities. © 2015 European Federation of Immunological Societies.
Humidity effect on the evolution of CsI thin films: a fractal study of rough surfaces
(Springer Science and Business Media Deutschland GmbH, 2023) Nabeel Jammal; R.P. Yadav; Richa Rai; Triloki; Alok Pandey; A.K. Mittal; B.K. Singh
The present work aims at studying the morphological, micro-structural, compositional and fractal features of CsI thin films, for the thicknesses 30, 50, 300 and 500 nm, in two cases: (i) as-deposited and (ii) 1-h humid air aged. The average grain sizes, estimated from TEM technique, are varied between the range 313–1058 nm, and their values are found to get increased after exposing to the humid air. The interplanar spacing evaluated from a SAED pattern is lesser than the standard value for a strain-free CsI crystal which suggests that a compressive stress is acting in the film. The compositional analysis suggests that the atomic percentage of Cs:I is 1:1, and it increased by the factor of two with exposure to humidity. The surface morphological images, captured by atomic force microscopy, signify the fractal behavior of CsI films. The values of the roughness exponent and fractal dimensions are determined for both as-deposited and humid-aged CsI films. It is observed that fractal parameters no longer remain unchanged after exposure to humidity, but they do not show any monotonic decreasing or increasing nature. The value of the roughness exponent was found to be greater than 0.5 which indicates that the height fluctuations at neighboring pixels are positively correlated. It signifies the height variations at neighboring pixels exhibit persistent behavior and memory effect. © 2023, The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature.
Impact of heavy metals on physiological processes of plants: With special reference to photosynthetic system
(Springer Singapore, 2016) Richa Rai; Madhoolika Agrawal; S.B. Agrawal
Heavy metal pollution is one of the major environmental problems which is caused by unchecked and uncontrolled discharge of hazardous chemicals consisting of heavy metals. Heavy metals affect agricultural land and plant’s productivity by affecting its most vital process, i.e., photosynthesis. Exposure of plants to heavy metals leads to generation of ROS, and few heavy metals are directly involved in electron transport. It also leads to lipid peroxidation destroying plant’s cell membrane and its associated organelles. Chlorophyll biosynthesis is affected by heavy metals as it substitutes Mg ion from chlorophyll. Few heavy metals also affect enzyme involved in chlorophyll biosynthesis as well as disturb electron transport in light reactions and affect various enzymes in dark reactions. This detailed information helps us to understand the mechanism linked with the impact of heavy metals on physiological responses affecting plant biomass and productivity which is of concern for agriculture. Therefore, the present chapter consists of whole information regarding the impact of heavy metals on photosynthetic pigments, photosynthetic apparatus, and light and dark reactions. © Springer Nature Singapore Pte Ltd. 2016.
Impact of tropospheric ozone on crop plants
(2012) Richa Rai; Madhoolika Agrawal
Tropospheric ozone (O3) is the most important regional atmospheric pollutant causing risk to food production across the globe due to its phytotoxicity and prevalence over agricultural areas. Peak O3 concentrations have declined in Europe and North America due to reductions in precursors during the last decades, however, emissions of O3 precursors have increased in Asia. The current critical level of ozone is determined by the threshold for yield loss which is based on the seasonal sum of the external concentration above 40 ppb. In the present article, the impact of tropospheric O3 on crop photosynthesis, defense mechanism, growth, reproductive processes and yield of crop plants have been documented. O 3 upon its entry into the leaf intercellular spaces rapidly forms reactive oxygen species and reacts with components of the leaf apoplast to initiate a complex set of responses that constitute variable countermeasures by antioxidative enzymes. Ozone affects photosynthetic process by influencing photosynthetic pigments, chlorophyll fluorescence kinetics and electron transport as well as carbon fixation in terms of decreased Rubisco activity and quantity. Translocation and allocation pattern of photosynthate also get influenced under O3, which affect reproductive processes and yield of crops. Plant species and cultivars exhibit a range of sensitivity to O 3, which is identifiable in terms of biochemical, physiological, molecular and yield responses. Hence, understanding of cultivar sensitivity in context to O3 would be helpful in development of potential O 3 biomarkers and O3 tolerant variables. © The National Academy of Sciences, India 2012.
Individual and interactive effects of elevated carbon dioxide and ozone on tropical wheat (Triticum aestivum L.) cultivars with special emphasis on ROS generation and activation of antioxidant defence system
(2013) Amit Kumar Mishra; Richa Rai; S.B. Agrawal
The effects of elevated CO2 and O3, singly and in combination were investigated on various physiological, biochemical and yield parameters of two locally grown wheat (Triticum aestivum L.) cultivars (HUW-37 and K-9107) in open top chambers (OTCs). Elevated CO2 stimulated photosynthetic rate (Ps) and Fv/Fm ratio and reduced the stomatal conductance (gs). Reactive oxygen species, lipid peroxidation, anti-oxidative enzymes, ascorbic acid and total phenolics were higher, whereas Ps, gs, Fv/Fm, protein and photosynthetic pigments were reduced in elevated O3 exposure, as compared to their controls. Under elevated CO2 + O3, elevated levels of CO2 modified the plant performance against O3 in both the cultivars. Elevated CO2 caused significant increase in economic yield. Exposure to elevated O3 caused significant reduction in yield and the effect was cultivar-specific. The study concluded that elevated CO2 ameliorated the negative impact of elevated O3 and cultivar HUW-37 was more sensitive to elevated O3 than K-9107.
Innate Immune Mechanism of Neutrophil Extracellular Trap Formation is Impaired in at-Risk Term Low Birth Weight Newborns
(Taylor and Francis Ltd., 2023) Doli Das; Vikas V. Singh; Sudhir K. Chauhan; Richa Rai; Ashok Kumar; Madhu Jain; Geeta Rai
Low birth weight (LBW) is a leading cause of newborn’s mortality however the underlying defects in cellular immunity and immune mechanisms leading to severe neonatal infections in term LBW (tLBW) newborns are not well understood. Neutrophil extracellular traps (NETs), or NETosis, is an innate immune defense mechanism of neutrophils involved in trapping and killing of microbes. The efficiency of NET formation in cord blood derived neutrophils of tLBW and normal birth weight (NBW) newborns in the presence of toll like receptor (TLR) agonist inductions was evaluated. The NET formation was observed to be substantially impaired in tLBW newborns along with NET proteins expression, extracellular deoxyribonucleic acid (DNA) release and reactive oxygen species generation. The placental tissues from tLBW newborns delivery also showed minimal NETosis. These findings suggest impaired NET formation to be an important factor underlying the deficient immune status of tLBW newborns making them susceptible to life- threatening infections. © 2023 Taylor & Francis Group, LLC.