Saini R.,Dr. B.R. Ambedkar University |
Singh P.,Dr. B.R. Ambedkar University |
Awasthi B.B.,Uttar Pradesh Pollution Control Board |
Kumar K.,Jawaharlal Nehru UniversityNew Delhi |
Taneja A.,Dr. B.R. Ambedkar University
Atmospheric Pollution Research | Year: 2014
Unplanned urban and industrial growth and rise in population are the main factors that had led to air pollution problems. Surface ozone causes human health problems and environmental degradation and acts as a greenhouse gas. Surface ozone is the most significant key substance of photochemical smog. Dependence of air pollutants on meteorology is described with the objective of understanding the prevailing processes pollutants phase interaction. Rigorous measurements of gaseous materials (surface O3, NO2, CO, and SO2) and particulate matter (PM2.5) were carried out regularly during the summer season of 2012 at kerbsite of Agra to assess the characteristics of air pollutants. The air mass trajectories have been calculated using the HYSPLIT 4 and FLEXTRA model. The maximum hourly levels of these pollutants exceeded 116.5 ppb for O3, 96.2 ppb for NO2, 16 ppb for SO2, 4.60 ppm for CO and 188 µg/m3 for PM2.5. There is obvious diurnal variation in the concentration of surface ozone which clearly follows the diurnal variation of atmospheric temperature. The joint application of principal component analysis and clustering techniques to data collected has led to the recognition of inherent relationships between variables that have been associated with governing processes related to surface O3 formation. The effect of wind on pollutants appears to be noteworthy. We also found that, the maximum average concentrations of SO2 and O3 occurred at humidity ≤30% pinpointing for strong vertical mixing. For CO, NO2 and PM2.5 the maximum average concentrations occurred at humidity below 40%. © Author(s) 2014.
Ishtikhar M.,Aligarh Muslim University |
Ali M.S.,King Saud University |
Atta A.M.,King Saud University |
Atta A.M.,Egyptian Petroleum Research Institute |
And 4 more authors.
Journal of Luminescence | Year: 2015
Abstract Biophysical insight into interaction of biocompatible rosin-based surfactants with human serum albumin (HSA) was studied at physiological conditions using various spectroscopic, calorimetric and molecular docking approaches. The binding constant (Kb), enthalpy (ΔH0), entropy (ΔS0) and Gibbs free energy change (ΔG0) were calculated by spectroscopic and calorimetric method. We have also calculated the probability of energy transfer by FRET analysis. The circular dichroism study showed that the cationic surfactant QRMAE significantly altered the secondary structure of HSA as compared to the nonionic rosin surfactants. The thermodynamic study was performed by ITC to determine binding constant as well as change in enthalpy of HSA in presence of rosin surfactants. It clearly showed that hydrogen binding and hydrophobic interaction play an important role in the binding of HSA to rosin surfactants. We have also performed molecular docking studies to locate the binding site on HSA and to visualize the mode of interaction. The present study provides a significant insight into HSA-rosin surfactants interaction, which also improves our understanding of the possible effect of rosin surfactants on human health. © 2015 Elsevier B.V.
Kumar S.,Jawaharlal Nehru UniversityNew Delhi |
Tiku A.B.,Jawaharlal Nehru UniversityNew Delhi
Food and Agricultural Immunology | Year: 2016
Plant polysaccharides have been reported to stimulate growth, differentiation and proliferation of hematopoietic progenitor and stem cells to protect against the deleterious effects of radiations. This study evaluated the radioprotective potential of acemannan, a major polysaccharide component of aloe vera gel. Treatment of mice with 50 mg/kg body weight of acemannan by oral gavage for 7 days was able to protect against the radiation-induced mortality. Seven-day pretreatment or post-treatment of mice with acemannan resulted in the increase in median survival by 60 and 20%, respectively. The decrease in mortality can be attributed to the induction of hematopoiesis (peripheral lymphocytes counts, spleen cellularity, spleen index) and the upregulation of cytokines like TNF-α and IL-1 by acemannan in irradiated mice. Data indicate that acemannan has the ability to protect mice against radiation-induced mortality by immunomodulation and can be developed as a radiation damage mitigation agent. © 2015 Taylor & Francis.
Pathak J.,Jawaharlal Nehru UniversityNew Delhi |
Rawat K.,Jawaharlal Nehru UniversityNew Delhi |
Rawat K.,Inter University Accelerator Center |
Bohidar H.B.,Jawaharlal Nehru UniversityNew Delhi
RSC Advances | Year: 2015
An understanding of the interactions between gelatin B (GB) and β-lacto-globulin (β-Lg) mainly arising from surface selective patch binding occurring at their common pI (≈5.0 ± 0.5) in the absence of added salt. Heterogeneous surface charge distribution on β-Lg facilitated such interaction at different mixing ratio ([GB]: [β-Lg] = r) and the GB-β-Lg complexes carried distinctive surface charge (seen through their zeta potential, ζ). For r < 1 : 1 (partial charge neutralization, ζ ≈ 0) a turbid solution was formed which gives the indication of formation of intermolecular soluble complexes. For r > 1 : 1 (overcharged regime, ζ > 0) the dispersion remained transparent and homogeneous which gives no phase separation, but the dispersion formed a gel on waiting. The overcharged gels were homogeneous, more rigid and higher melting temperature in comparison to coacervate. In the coacervate phase, the intensity of the scattered light Is, and its time-correlation function [g2(t) - 1] did not evolve with time. In contrast, the gel phase displayed considerable change with aging time tw. For gels, as tw → ∞ the system moved from an ergodic to non-ergodic state. At tw = 0, the correlation function exhibited one relaxation mode due to the system residing deeply inside the ergodic phase and purely mirroring Brownian dynamics. After a characteristic waiting time, tw an additional mode (slow relaxation) appeared which was attributed to inter-chain interaction induced reorganization of entanglements. This characteristic time was the time required for the system to get dynamically arrested, similar observation was made from rheology measurements too. A comprehensive phase diagram depicting the stability of the dispersion in various charged soft matter states of the complex under various temperature conditions was established. This journal is © The Royal Society of Chemistry.
Dev S.,Jawaharlal Nehru UniversityNew Delhi |
Kumari S.,Jawaharlal Nehru UniversityNew Delhi |
Singh N.,Case Western Reserve University |
Kumar Bal S.,Jawaharlal Nehru UniversityNew Delhi |
And 2 more authors.
Free Radical Biology and Medicine | Year: 2015
Abstract Iron accumulation and oxidative stress are associated with neurodegenerative disease. Labile iron is known to catalyze free radical generation and subsequent neuronal damage, whereas the role of oxidative stress in neuronal iron accumulation is less well understood. Here, we examined the effect of hydrogen peroxide (H2O2) treatment on cellular iron-uptake, -storage, and -release proteins in the neuroblastoma cell line SH-SY5Y. We found no detectable change in the iron-uptake proteins transferrin receptor-1 and divalent metal ion transporter. In contrast, H2O2 treatment resulted in significant degradation of the iron-exporter ferroportin (Fpn). A decrease in Fpn is expected to increase the labile iron pool (LIP), reducing the iron-regulatory protein (IRP)-iron-responsive element interaction and increasing the expression of ferritin-H (Ft-H) for iron storage. Instead, we detected IRP1 activation, presumably due to oxidative stress, and a decrease in Ft-H translation. A reduction in Ft-H mRNA was also observed, probably dependent on an antioxidant-response element present in the Ft-H enhancer. The decrease in Fpn and Ft-H upon H2O2 treatment led to a time-dependent increase in the cellular LIP. Our study reveals a complex regulation of neuronal iron-release and iron-storage components in response to H2O2 that may explain iron accumulation detected in neurodegenerative diseases associated with oxidative stress. © 2015 Elsevier Inc.