| 1. |
- Arora, Neha, et al.
(författare)
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NMR-Based Metabolomic Approach To Elucidate the Differential Cellular Responses during Mitigation of Arsenic(III, V) in a Green Microalga
- 2018
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Ingår i: ACS Omega. - : American Chemical Society (ACS). - 2470-1343. ; 3:9, s. 11847-11856
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Tidskriftsartikel (refereegranskat)abstract
- Nuclear magnetic resonance (NMR)-based metabolomic approach is a high-throughput fingerprinting technique that allows a rapid snapshot of metabolites without any prior knowledge of the organism. To demonstrate the applicability of NMR-based metabolomics in the field of microalgal-based bioremediation, novel freshwater microalga Scenedesmus sp. IITRIND2 that showed hypertolerance to As(III, V) was chosen for evaluating the metabolic perturbations during arsenic stress in both its oxidation states As(III) and As(V). Using NMR spectroscopy, we were able to identify and quantify an array of ∼45 metabolites, including amino acids, sugars, organic acids, phosphagens, osmolytes, nucleotides, etc. The NMR metabolomic experiments were complemented with various biophysical techniques to establish that the microalga tolerated the arsenic stress using a complex interplay of metabolites. The two different arsenic states distinctly influenced the microalgal cellular mechanisms due to their altered physicochemical properties. Eighteen differentially identified metabolites related to bioremediation of arsenic were then correlated to the major metabolic pathways to delineate the variable stress responses of microalga in the presence of As(III, V).
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| 2. |
- Bhatt, Pramod, et al.
(författare)
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Correlation of structural, chemical and magnetic properties in annealed Ti/Ni multilayer structures
- 2005
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 97:4, s. 043509-
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Tidskriftsartikel (refereegranskat)abstract
- Ti/Ni multilayer samples have been synthesized on float glass substrates using an electron-beam evaporation technique under ultrahigh vacuum conditions at room temperature. Grazing incidence x-ray diffraction (GIXRD) and grazing incidence x-ray reflectivity (GIXRR) techniques were used, respectively, to study structural modifications and to determine corresponding changes in microstructural parameters, such as individual layer thickness, interface roughness, and electron density due to annealing treatment. In addition to this, the chemical nature of the surface and interfaces of these samples were also studied using a depth profile x-ray photoelectron spectroscopy (XPS) technique. The GIXRD measurement show clear amorphization of the as-deposited multilayer sample annealed in the temperature range of 300–400 °C. The corresponding GIXRR measurement indicates the formation of a sufficiently thick layer of Ti–Ni at interfaces converting the Ti/Ni bilayer into a Ti/Ti–Ni/Ni trilayer multilayer structure. The precipitation of the Ti–Ni alloy phase at the interface in the case of samples annealed at 400 °C has been confirmed by XPS measurements. The magnetization behavior investigated using the magneto-optical Kerr effect technique clearly shows well the saturation magnetization behavior for all samples annealed up to 300 °C, while the sample annealed at 400 °C does not show saturation magnetization. The corresponding coercivity value (Hc) is also found to be changed drastically from 15.5 to 0.6 Oe. This observed magnetization behavior is discussed and correlated with structural and chemical changes in the multilayer structure.
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| 3. |
- Block, Keith I., et al.
(författare)
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Designing a broad-spectrum integrative approach for cancer prevention and treatment
- 2015
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Ingår i: Seminars in Cancer Biology. - : Academic Press. - 1044-579X .- 1096-3650. ; 35, s. S276-S304
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Forskningsöversikt (refereegranskat)abstract
- Targeted therapies and the consequent adoption of "personalized" oncology have achieved notable successes in some cancers; however, significant problems remain with this approach. Many targeted therapies are highly toxic, costs are extremely high, and most patients experience relapse after a few disease-free months. Relapses arise from genetic heterogeneity in tumors, which harbor therapy-resistant immortalized cells that have adopted alternate and compensatory pathways (i.e., pathways that are not reliant upon the same mechanisms as those which have been targeted). To address these limitations, an international task force of 180 scientists was assembled to explore the concept of a low-toxicity "broadspectrum" therapeutic approach that could simultaneously target many key pathways and mechanisms. Using cancer hallmark phenotypes and the tumor microenvironment to account for the various aspects of relevant cancer biology, interdisciplinary teams reviewed each hallmark area and nominated a wide range of high-priority targets (74 in total) that could be modified to improve patient outcomes. For these targets, corresponding low-toxicity therapeutic approaches were then suggested, many of which were phytochemicals. Proposed actions on each target and all of the approaches were further reviewed for known effects on other hallmark areas and the tumor microenvironment Potential contrary or procarcinogenic effects were found for 3.9% of the relationships between targets and hallmarks, and mixed evidence of complementary and contrary relationships was found for 7.1%. Approximately 67% of the relationships revealed potentially complementary effects, and the remainder had no known relationship. Among the approaches, 1.1% had contrary, 2.8% had mixed and 62.1% had complementary relationships. These results suggest that a broad-spectrum approach should be feasible from a safety standpoint. This novel approach has potential to be relatively inexpensive, it should help us address stages and types of cancer that lack conventional treatment, and it may reduce relapse risks. A proposed agenda for future research is offered. (C) 2015 The Authors. Published by Elsevier Ltd.
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