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Accumulation of hemin in cells, tissues, and organs is one of the major pathological conditions linked to hemolytic diseases like malaria. Pro-oxidant hemin confers high toxicity following its accumulation. We tested the cellular toxicity of hemin on HepG2 cells by exploring modulation in various cellular characteristics. Hemin reduces the viability of HepG2 cells and brings about visible morphological changes. Hemin causes perforations on the surface of HepG2 cells observed through SEM. Hemin leads to the extracellular release of liver enzymes and reduces the wound-healing potential of HepG2 cells. Hemin leads to the fragmentation of HepG2 DNA, arrests the cell cycle progression in the S-phase and induces apoptosis in these cells. Western blot analysis revealed that hemin triggers both the extrinsic and intrinsic pathways of apoptosis in HepG2 cells. We have already shown that the cytoprotective protein HSPA8 can polymerize hemin and minimize its toxicity. Similar experiments with hemin in the presence and absence of HSPA8 showed that HSPA8 reverses all the tested toxic effects of hemin on HepG2 cells. The protection from hemin toxicity in HepG2 cells appeared to be due to the extracellular polymerization of hemin by HSPA8. • Hemin reduces cell viability and causes morphological changes in HepG2 cells. • Hemin causes the release of liver damage-associated enzymes from hepatocytes. • Hemin mitigates the wound-healing potential of HepG2 cells. • Hemin leads to cell cycle arrest and induces apoptosis in HepG2 cells. • HSPA8 impedes the toxic effects of hemin on HepG2 cells. [ABSTRACT FROM AUTHOR]

This paper emphasizes on examining the impact of Soret-Dufour effects and anisotropic slip on the MHD (magnetohydrodynamics) flow of tangent hyperbolic fluid over a rotating disk. The fluid is assumed to be flowing because of the rotating disk with variable thickness. The fluid thermal conductivity and dynamic viscosity are dependent on temperature. The Legendre wavelet collocation method (LWCM) is employed to obtain the numerical solution of the non-linear ordinary differential equations. The influence of several parameters, such as the Weissenberg number, variable dynamical viscosity, variable thermal conductivity, slip parameters, thickness coefficient, magnetic field, Soret-Dufour numbers, Schmidt number, and Eckert number, on the velocities, temperature, and concentration profiles are examined. The validation of the results of LWCM is revealed with existing work. The values of skin friction coefficients, local Nusselt number, and local Sherwood number are provided for two cases: suction and injection. The temperature profiles of tangent hyperbolic fluid enhanced with increasing the values of Soret and Dufour numbers in presence of suction/injection region. In the injection region, as the magnetic field parameter increased from 0 to 0.1, the local Nusselt number rise up to 1.04 %. Furthermore, in the suction region, the local Nusselt number rise up to 0.89 %. [ABSTRACT FROM AUTHOR]

This study examines the spatio-temporal trends obtained from decade long (Jan 2003–Dec 2014) satellite observational data of Atmospheric Infrared Sounder (AIRS) and Measurements of Pollution in the Troposphere (MOPITT) on carbon monoxide (CO) concentration over the Indo-Gangetic Plains (IGP) region. The time sequence plots of columnar CO levels over the western, central and eastern IGP regions reveal marked seasonal behaviour, with lowest CO levels occurring during the monsoon months and the highest CO levels occurring during the pre-monsoon period. A negative correlation between CO levels and rainfall is observed. CO vertical profiles show relatively high values in the upper troposphere at ∼200 hPa level during the monsoon months, thus suggesting the role of convective transport and advection in addition to washout behind the decreased CO levels during this period. MOPITT and AIRS observations show a decreasing trend of 9.6 × 10 15 and 1.5 × 10 16 molecules cm −2 yr −1 , respectively, in columnar CO levels over the IGP region. The results show the existence of a spatial gradient in CO from the eastern (higher levels) to western IGP region (lower levels). Data from the Census of India on the number of households using various cooking fuels in the IGP region shows the prevalence of biomass-fuel (i.e. firewood, crop residue, cowdung etc.) use over the eastern and central IGP regions and that of liquefied petroleum gas over the western IGP region. CO emission estimates from cooking activity over the three IGP regions are found to be in the order east > central > west, which support the existence of the spatial gradient in CO from eastern to the western IGP region. Our results support the intervention of present Indian government on limiting the use of biomass-fuels in domestic cooking to achieve the benefits in terms of the better air quality, household health and regional/global climate change mitigation. [ABSTRACT FROM AUTHOR]

The flow of fluid over a surface that is being stretched has numerous important potential uses, such as polymer extrusion, coating, etc. The objective of this study is to investigate the characteristics of flow attributes (velocity, temperature, skin friction coefficient, and local Nusselt number) under specific conditions, when a quadratic convective flow of tangent hyperbolic fluid is applied over a non-flat stretching sheet. In this case, the transfer of heat is simulated by employing a modified version of Fourier's law and complemented with quadratic thermal radiation. The resolution of the governing partial differential equations is achieved by initially transforming them into ordinary differential equations and subsequently employing the Legendre wavelet collocation technique (LWCT). Moreover, β − cut technique of fuzzy numbers are utilized in ODEs to obtained FDEs (Fuzzy differential equation) and FDEs are solved by triangular fuzzy number (TFN). The numerical computation involves the treatment of We and Rd as fuzzy numbers. The findings suggest that the fluid temperature drops when the relaxation parameter is raised. Moreover, Fuzzy temperature profile decreases with increasing A 1 , A 2 and fuzzy parameter β. The current code demonstrates a high degree of concurrence when subjected to numerical validation in comparison to prior research. [ABSTRACT FROM AUTHOR]

Abstract: The indiscriminate use of pesticides and herbicides to increase crop productivity has aroused a great concern among the environmental and health scientists due to their adverse effects in both target as well as non-target species. Although substantial information is available regarding their environmental and ecological impact, not much is known in regard to its toxicity in the mammalian system. Therefore a study was conducted for the assessment of cytotoxic and genotoxic effects of cypermethrin (Type II pyrethroid) dichlorvos (organophosphate) and pendimethalin (dinitroaniline herbicide) in Chinese hamster ovary (CHO) cells. CHO cells were exposed to 1μM, 10μM, 100μM, 1000μM, and 10,000μM, cypermethrin, pendimethalin and dichlorvos for 3h and cytotoxicity was assessed by MTT assay. Their genotoxic potential was also evaluated by Comet assay. The results demonstrate that dichlorvos and pendimethalin exhibited higher extent of cytotoxicity as compared to cypermethrin. A significant (p <0.05) concentration dependent increase in DNA damage was observed with dichlorvos (0.01μM and above) and pendimethalin (0.1μM and above) as evident by Comet assay parameters viz., Olive tail moment (arbitrary units), tail DNA (%) and tail length (μM). Cypermethrin induced a significant (p <0.05) DNA damage only at higher concentrations (1000 and 5000μM). Our data indicates that these chemicals produce cytotoxicity and DNA damage in mammalian cells and should be used with caution. [Copyright &y& Elsevier]

Abstract In this study, an evaluation of physico-chemical properties, cytotoxicity and genotoxicity of candle soot derived carbon nanoparticles (CNPs) was carried out. Several physico-chemical characterizations including scanning electron microscopy, transmission electron microscope, Brunauer-Emmet-Teller surface area and pore-size distribution, X-ray diffraction, Fourier transform infrared and Raman spectroscopy were implemented to characterize prepared CNPs. Propidium iodide uptake, reactive oxygen species assay and trypan blue exclusion and comet assay tests were executed to determine the toxicity of CNPs. It is found that the CNPs have insignificant cytotoxicity and genotoxicity and could be used in diverse biological and environmental applications as an alternative to expensive less toxic carbon materials. Highlights • Physico-chemical properties, cytotoxicity and genotoxicity of CNPs was carried out. • CNPs have insignificant cytotoxicity and genotoxicity. • No significant DNA damage is observed in CNPs exposed V-79 cells. • Could be used as an alternative of expensive carbon materials. [ABSTRACT FROM AUTHOR]

The unique physico-chemical properties of nano crystalline anatase titanium dioxide nanoparticles (TiO 2 NPs) render them with different biological and chemical activities. Hence, it is widely used in industrial and consumer applications. Previous studies have shown the genotoxicity of TiO 2 NPs. However, there is a paucity of data regarding mutagenicity of these NPs. In the present study, the cellular uptake, sub-cellular localization, cytotoxicity and short term DNA interaction of TiO 2 NPs (1–100 μgmL −1 ) of diameter ranging from 12 to 25 nm on mammalian lung fibroblast cells (V-79) has been studied. The flow cytometric analysis and electron micrographs of V-79 monolayer showed the internalization of TiO 2 NPs in the cytoplasm with the confirmation of elemental composition through SEM/EDX analysis. TEM analysis also showed TiO 2 NPs induced ultra-structural changes such as swollen mitochondria and nuclear membrane disruption in V-79 cells. TiO 2 NPs generated free radicals, which induced indirect mutagenic and genotoxic responses. Apart from measuring the genotoxicity by Comet assay, the mutagenic potential of TiO 2 NPs in V-79 cells was evaluated by mammalian HGPRT gene forward mutation assay, showing a 2.98- fold increase in 6TG R HGPRT mutant frequency (*p < 0.05, **p < 0.01, ***p < 0.001) by culture plate method, which is an early indicator of potential carcinogenicity. Hence, TiO 2 NPs should be closely monitored and there should be a judicious use and disposal of NPs. [ABSTRACT FROM AUTHOR]

The wide application of zinc oxide nanoparticles (ZnO NPs) in cosmetics, paints, biosensors, drug delivery, food packaging and as anticancerous agents has increased the risk of human exposure to these NPs. Earlier in vitro and in vivo studies have demonstrated a cytotoxic and genotoxic potential of ZnO NPs. However, there is paucity of data regarding their immunomodulatory effects. Therefore, the present study was aimed to investigate the immunotoxic potential of ZnO NPs using human monocytic cell line (THP-1) as model to understand the underlying molecular mechanism. A significant (p < 0.01) increase in pro-inflammatory cytokines (TNF-α and IL-1β) and reactive oxygen species (ROS) was observed with a concomitant concentration dependent (0.5, 1, 5, 10, 15 and 20 μg/mL) decrease in the glutathione (GSH) levels as compared to control. The expression levels of mitogen activated protein kinase (MAPK) cascade proteins such as p-ERK1/2, p-p38 and p-JNK were also significantly (p < 0.05, p < 0.01) induced. Also, at the concentration tested, NPs induced DNA damage as assessed by the Comet and micronucleus assays. Our data demonstrated that ZnO NPs induce oxidative and nitrosative stress in human monocytes, leading to increased inflammatory response via activation of redox sensitive NF-κB and MAPK signalling pathways. [ABSTRACT FROM AUTHOR]