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Dhiman M.,Panjab University | Sharma R.,Panjab University | Kumar V.,Icon Analytical Equipment Pvt. Ltd. | Singhal S.,Panjab University
Ceramics International | Year: 2016

The present work is focused on studying morphology dependent catalysis of spinel ZnFe2O4 nanostructures. Different morphologies i.e. porous nanorods, nanoparticles, nanoflowers and hollow microspheres were designed hydrothermally. The as prepared nanomaterials were characterized using Fourier Transform Infra-Red (FTIR), field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HR-TEM), powder X-ray diffraction (XRD), vibrating sample magnetometer (VSM), Brunauer-Emmett-Teller (BET) technique and UV-visible spectrophotometer. The results confirmed formation of desired morphologies of cubic spinel ZnFe2O4 with high surface areas (92-138m2/g) and narrow band gaps (1.76-1.97eV). It suggested the use of ZnFe2O4 nanostructures as potential visible light photocatalysts. Therefore, the application of synthesized ZnFe2O4 nanostructures was studied in photo-Fenton degradation of dyes. The results indicated shape dependent relationship with photocatalytic activity as the degradation of dyes followed the order porous nanorods>nanoparticles>nanoflowers>hollow microspheres. The role of main active species in the reaction i.e. (bullet operator)OH was also confirmed. All the materials exhibited stability and magnetic separability hence could act as potential photo-Fenton catalysts for wastewater treatment. © 2016 Elsevier Ltd and Techna Group S.r.l.

Nayek C.,Indian Institute of Technology Madras | Samanta S.,Indian Institute of Technology Madras | Manna K.,Indian Institute of Science | Pokle A.,Icon Analytical Equipment Pvt. Ltd. | And 3 more authors.
Physical Review B - Condensed Matter and Materials Physics | Year: 2016

We report the transition from robust ferromagnetism to a spin-glass state in nanoparticulate La0.7Sr0.3MnO3 through solid solution with BaTiO3. The field- and temperature-dependent magnetization and the frequency-dependent ac magnetic susceptibility measurements strongly indicate the existence of a spin-glass state in the system, which is further confirmed from memory effect measurements. The breaking of long-range ordering into short-range magnetic domains is further investigated using density-functional calculations. We show that Ti ions remain magnetically inactive due to insufficient electron leakage from La0.7Sr0.3MnO3 to the otherwise unoccupied Ti-d states. This results in the absence of a Mn-Ti-Mn spin exchange interaction and hence the breaking of the long-range ordering. Total-energy calculations suggest that the segregation of nonmagnetic Ti ions leads to the formation of short-range ferromagnetic Mn domains. © 2016 American Physical Society.

Khan S.,National Institute of Pharmaceutical Education and Research | Jena G.,National Institute of Pharmaceutical Education and Research | Tikoo K.,National Institute of Pharmaceutical Education and Research | Kumar V.,Icon Analytical Equipment Pvt. Ltd.
Biochimie | Year: 2015

Epigenetic modifications are increasingly recognized to play a significant contribution in diabetic nephropathy (DN). Histone deacetylases (HDACs) are the emerging target in the pathogenesis and progression of DN. Valproic acid (VPA), a widely used anti-epileptic drug and has been proven as an HDAC inhibitor. This study was aimed to evaluate the protective roles of VPA on HDAC-mediated NF-κB/iNOS signaling and autophagy in DN. Diabetes was induced by a single injection of STZ (50 mg/kg), whereas VPA at the doses of 150 and 300 mg/kg/day for 8 weeks was administered by oral route in Sprague-Dawley rat. Blood and urine were collected before animal were sacrificed, while kidneys were dissected after sacrificed. The podocyte and renal injuries were assessed using biochemical markers, histology, podocyte effacement, DNA damage and apoptosis as well as protein expression evaluation. VPA treatment improves the plasma and urinary biomarkers of renal function, decreased expression of iNOS, 3-nitrotyrosine, NF-κB, p-NF-κB, HDAC4/5, calmodulin, calbindin, apoptosis and DNA damage. Further, VPA treatment increased histone acetylation and ameliorated the histological alterations and podocyte effacement. Interestingly, VPA treatment also restored diabetes-associated perturbations in autophagy by HDAC inhibition. To the best of our knowledge, this is the first report, which highlights the beneficial role of VPA in DN. The present results clearly exhibited that VPA treatment ameliorates the podocyte and renal injuries mainly by facilitating the autophagy and inactivation of NF-κB/iNOS signaling. The present findings demonstrated that VPA may be useful in the treatment of DN, since the present experimental doses are clinically relevant. © 2014 Elsevier B.V. and Société française de biochimie et biologie Moléculaire (SFBBM).

Arbuj S.S.,CMET - Photonics And Advanced Materials Laboratory | Rumale N.,ELANTAS Beck India Ltd. | Pokle A.,Icon Analytical Equipment Pvt. Ltd. | Ambekar J.D.,CMET - Photonics And Advanced Materials Laboratory | And 3 more authors.
Science of Advanced Materials | Year: 2014

A highly crystalline ZnO nano pencils/rods were successfully synthesized via low cost and template free solvothermal method. The reaction was carried out at 200°C for 2, 5 and 12 h respectively. The reaction time enhances the photoluminescent properties of ZnO, mainly the intensity of green emission band increased. X-ray diffraction revealed the formed products have a wurtzite structure. The morphology and microstructure analyses of ZnO nano pencils/rods were performed by field emission scanning electron microscopy and transmission electron microscopy. The ZnO nanorods are about 20 to 70 nm in width and length varies from nm to sub-micron size. TEM confirms formation of pencil and rod shaped ZnO nanostructures. ZnO synthesized using different reaction time showed UV-Visible absorbance at 372 nm. Photoluminescence measurement showed UV emission peak and broad yellow-green emission peak centered at 390 and 500 nm respectively. Photocatalytic activity of synthesized ZnO was evaluated by following the degradation of aqueous methylene blue dye. Change in the photocatalytic activity was observed with change in reaction time of ZnO synthesis. ZnO prepared at 2 h of reaction time showed apparent rate constant (Kapp) of 8.8×10-2 min-1 for MB degradation. © 2014 by American Scientific Publishers.

Trivedi P.P.,National Institute of Pharmaceutical Education and Research | Jena G.B.,National Institute of Pharmaceutical Education and Research | Tikoo K.B.,National Institute of Pharmaceutical Education and Research | Kumar V.,Icon Analytical Equipment Pvt. Ltd.
Molecular Carcinogenesis | Year: 2016

Colon carcinogenesis is long known to be associated with ulcerative colitis (UC), a chronic gastrointestinal disorder. Various pre-clinical and clinical studies have shown that melatonin (MEL) has beneficial effects in cancer. However, elucidation of the detailed molecular mechanisms involved in MEL-mediated protection against the colon carcinogenesis deserves further investigation. The present study was aimed at deciphering the effect of MEL on autophagy and Nrf2 signaling pathways in a mouse model of colitis-associated colon carcinogenesis (CACC). For the induction of CACC, male Swiss Albino mice were administered a single ip injection of 20mg 1, 2-dimethylhydrazine dihydrochloride (DMH)/kg bw, followed by 3 cycles of 3% w/v dextran sulfate sodium (DSS) in drinking water treatment initiated 1wk after DMH injection. One week after the initiation of DSS treatment, MEL was administered at the dose of 1mg/kg, bw, po for 8 and 18 wk. Mice were sacrificed at 10 and 20wk after DMH injection. MEL treatment decreased the progression of CACC by down regulating the process of autophagy as revealed by the expression pattern of various autophagy markers such as Beclin-1, LC3B-II/LC3B-I ratio and p62. These findings were accompanied with the increased expression of Nrf2 and the associated antioxidant enzymes, NAD(P)H:quinone oxidoreductase (NQO-1) and heme oxygenase-1 (HO-1) in the colon of mice with CACC. MEL intervention reduced autophagy by ameliorating inflammation and oxidative stress in the colon of mice with CACC. We conclude that MEL treatment attenuates the progression of CACC in mice by modulating autophagy and Nrf2 signaling pathways. © 2016 Wiley Periodicals, Inc.

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