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Heavy metal pollution is a prevalent and critical environmental concern. Its rampancy is attributed to indiscriminate anthropogenic activities. Several technologies including biosorption have been continuously researched upon to overcome the limitations of the conventional method of treatments in removal of heavy metals. Biosorption technology involves the application of a biomass in its nonliving form. Pteris vittata L., a pteridophyte, considered as an invasive weed was investigated in the present study as a potential decontaminant of toxic metals, Cr(VI) and Cd(II). The adsorption capacity of the biosorbent for Cr(VI) and Cd(II) under equilibrium conditions was investigated. The morphology, elemental composition, functional groups, and thermal stability of the biosorbent before and after metal loading were evaluated. At 303?K and an equilibrium time of 120?min, the maximum loading of Cr(VI) on the biosorbent was estimated to be 166.7?mg/g at pH 2 and Cd(II) to be 31.3?mg/g at pH 6. Isotherm models, kinetic studies, and thermodynamic studies indicated the mechanisms, chemisorption, ion exchange and intraparticle diffusion, controlling the Cr(VI) and Cd(II) uptake, respectively. The interactive effect of multi-metal ions in binary component systems was synergistic for Cd(II) uptake. The results validate the toxic metal removal potency of the biosorbent. 相似文献
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Vijendra Prabhu Satish B. S. Rao Subhash Chandra Pramod Kumar Lakshmi Rao Vasudeva Guddattu Kapaettu Satyamoorthy Krishna K. Mahato 《Journal of biophotonics》2012,5(2):168-184
The present study focuses on the evaluation of the effect of He‐Ne laser on tissue regeneration by monitoring collagen synthesis in wound granulation tissues in Swiss albino mice using analysis of laser induced fluorescence (LIF) and light microscopy techniques. The spectral analyses of the wound granulation tissues have indicated a dose dependent increase in collagen levels during the post‐wounding days. The histological examinations on the other hand have also shown a significant increase in collagen deposition along with the reduced edema, leukocytes, increased granulation tissue, and fibroblast number in the optimal laser dose treated group compared to the non‐illuminated controls. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Gayathri S. Prabhu Keerthana Prasad Mohandas Rao K.G. Kiranmai S. Rai 《Saudi Journal of Biological Sciences》2021,28(4):2396-2407
IntroductionThe aim of this study was to assess the efficacy of choline and DHA or exposure to environmental enrichment in obese adult and aging rats on alterations in body mass index, serum lipid profile and arterial wall changes, despite stopping high fat diet consumption and interventions during adulthood.Methods21 day old male Sprague Dawley rats were assigned as Experiment-1 & 2 - PND rats were divided into 4 groups with interventions for 7 months (n = 8/group). NC– Normal control fed normal chow diet; OB- Obese group, fed high fat diet; OB + CHO + DHA- fed high fat diet and oral supplementation of choline, DHA. OB + EE- fed high fat diet along with exposure to enriched environment .Experiment-2 had similar groups and interventions as experiment 1 but for next 5 months were fed normal chow diet without any interventions. Body mass index was assessed and blood was analyzed for serum lipid profile. Common Carotid Artery (CCA) was processed for Haematoxylin and eosin, Verhoff Vangeison stains. Images of tissue sections were analyzed and quantified using image J and tissue quant software.ResultsIn experiment.1, mean body mass index (p < 0.001), serum lipid profile (p < 0.01), thickness of tunica intima (p < 0.05), tunica media (p < 0.01) and percentage of collagen fibers (p < 0.01) of CCA were significantly increased in OB compared to NC. These were significantly attenuated in OB + CHO + DHA and OB + EE compared to OB. In experiment.2, mean body mass index (p < 0.01), serum lipid profile (p < 0.05) and thickness of tunica media of CCA (p < 0.01) were significantly increased in OB compared to NC. In OB + CHO + DHA and OB + EE, significant attenuation was observed in mean body mass index and mean thickness of tunica media compared to same in OB.ConclusionAdult obesity has negative impact on body mass index, serum lipid profile and arterial wall structure that persists through aging. Supplementation of choline and DHA or exposure to enriched environment during obesity attenuates these negative impacts through aging. 相似文献
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Reenu Singh Tanwar Krishna Madhava Prabhu 《Redox report : communications in free radical research》2017,22(6):301-307
Objectives: Eugenia jambolana (E. jambolana) is well known for its antidiabetic potential. The aim of the present study was to investigate the antidiabetic and antioxidative effect of an active compound (FIIc) isolated from fruit-pulp of E. jambolana in streptozotocin (45?mg/kg body weight)-induced diabetic rats.Methods: FIIc was isolated from the crude aqueous extract of fruit-pulp by ion-exchange column chromatography and high-performance column chromatography. Detailed UV, NMR, and IR spectra suggested that FIIc is α-hydroxy succinamic acid. FIIc was orally administered to diabetic rats at a dose of 10, 15, and 20?mg/kg body weight (mg/kg bwt.) to determine its effective dose. Thereafter, effective dose was administered to 8 weeks to determine its antidiabetic and antioxidative activity by estimation of glycemic index, lipid profile, key enzymes of carbohydrate metabolism, and oxidative stress parameters.Results: Administration of 15?mg/kg dose daily for 8 weeks led to significant (P?0.001) fall in fasting blood glucose. Treatment with FIIc (15?mg/kg bwt.) showed significant improvement (P?0.001) in all the biochemical parameters.Discussion: The results demonstrate that FIIc possesses significant antidiabetic and antioxidative activity. 相似文献
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