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Soumadri Samanta Sunil Kumar V. R. Battula Arpna Jaryal Neha Sardana Kamalakannan Kailasam 《RSC advances》2020,10(50):29633
Metal-free organic polymer photocatalysts have attracted dramatic attention in the field of visible light-induced hydrogen evolution reaction (HER). Herein, we showed a polymeric O-linked heptazine polymer (OLHP) decorated with S, N co-doped graphene quantum dots (S,N-GQDs) as a photosensitizer to generate hydrogen upon quantum dot sensitization. Both of these heptazine-based systems show effective photosensitization with strong π–π interactions and enhanced photocatalytic H2 generation (24 times) as metal-free systems. Electrochemical impedance and optical measurements show effective charge transfer kinetics with decreased charge recombination, which is responsible for the enhanced photocatalytic activity. As a result, a significant high apparent quantum yield (AQY) with highest value of 10.2% was obtained for our photocatalyst OLHP/S,N-GQD10.A polymeric O-linked heptazine polymer (OLHP) decorated with S, N co-doped graphene quantum dots (S,N-GQDs) as a photosensitizer to utilize visible light (λ > 420 nm) for hydrogen generation. 相似文献
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Preethi Jeyaraman Narendra Agrawal Rahul Bhargava Divya Bansal Rayaz Ahmed Dinesh Bhurani Sachin Bansal Neha Rastogi Pronamee Borah Rahul Naithani 《Transfusion and apheresis science》2021,60(3):103075
BackgroundData on convalescent plasma therapy (CPT) in patients of hematological malignancies with severe Covid-19 is scarce.ObjectiveTo study 14-day mortality in patients who received CPT.Patients & methodsRetrospective multicentre observational study conducted in 4 centres treating haematological malignancies across Delhi-national capital region. Total 33 haematological malignancies patients with severe Covid-19 who received CPT were analysed.ResultsThe median age of the study cohort was 62 years (18–80 years). Twenty one percent patients had 1 comorbidity, 18 % had 2 comorbidities and 6% patients had 3 and 5 comorbidities each. Twenty four patients were on active therapy. Sixty nine percent of patients required ICU stay. Twenty five patients received plasma therapy within 7 days (early) of diagnosis of Covid-19 infection. Median day of plasma infusion from date of diagnosis of Covid-19 infection was 4 days (range: 2–25 days). Patient who had early initiation of plasma therapy had shorter duration of hospitalisation (12.7 vs 24.3 days, p = 0.000). Overall mortality in the cohort was 45.5%. There was no effect of disease status, active therapy, presence of comorbidity on mortality. There was no difference in the mortality in patients receiving early vs late initiation of plasma therapy or in patients receiving one versus two plasma therapy.ConclusionsWe provide a large series of patients with hematological malignancies and role of CPT in this group. 相似文献
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Suman Srivastava Neha Thakur Ashutosh Singh Poonam Shukla Vipin Kumar Maikhuri Neha Garg Ashok Prasad Rampal Pandey 《RSC advances》2019,9(51):29856
A new fluorescent sensor 5 based on a fused imidazopyridine scaffold has been designed and synthesized via cascade cyclization. The reaction features the formation of three different C–N bonds in sequence. Imidazopyridine based fluorescent probe 5 exhibits highly sensitive and selective fluorescent sensing for Fe3+(‘turn-on’) and Hg2+(‘turn-off’). The excellent selectivity of imidazopyridine for Fe3+/Hg2+ was not hampered in the presence of any of the competing cations. The limit of detection (LOD) of 5 toward Fe3+ and Hg2+ has been estimated to be 4.0 ppb and 1.0 ppb, respectively, with a good linear relationship (R2 = 0.99). Notably, 5 selectively detects Fe3+/Hg2+ through fluorescence enhancement signalling both in vitro and in HeLa cells.A new fluorescent sensor 5 having fused imidazopyridine scaffold has been synthesized via cascade cyclization. It exhibits highly sensitive and selective detection of Fe3+ (‘turn-on’) and Hg2+ (‘turn-off’) in vitro and in HeLa cells. 相似文献
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Andrea Franceschini Roger Meier Alain Casanova Saskia Kreibich Neha Daga Daniel Andritschke Sabrina Dilling Pauli R?m? Mario Emmenlauer Andreas Kaufmann Raquel Conde-álvarez Shyan Huey Low Lucas Pelkmans Ari Helenius Wolf-Dietrich Hardt Christoph Dehio Christian von Mering 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(12):4548-4553
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Sehgal N Gupta A Valli RK Joshi SD Mills JT Hamel E Khanna P Jain SC Thakur SS Ravindranath V 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(9):3510-3515
A 30-d course of oral administration of a semipurified extract of the root of Withania somnifera consisting predominantly of withanolides and withanosides reversed behavioral deficits, plaque pathology, accumulation of β-amyloid peptides (Aβ) and oligomers in the brains of middle-aged and old APP/PS1 Alzheimer's disease transgenic mice. It was similarly effective in reversing behavioral deficits and plaque load in APPSwInd mice (line J20). The temporal sequence involved an increase in plasma Aβ and a decrease in brain Aβ monomer after 7 d, indicating increased transport of Aβ from the brain to the periphery. Enhanced expression of low-density lipoprotein receptor-related protein (LRP) in brain microvessels and the Aβ-degrading protease neprilysin (NEP) occurred 14-21 d after a substantial decrease in brain Aβ levels. However, significant increase in liver LRP and NEP occurred much earlier, at 7 d, and were accompanied by a rise in plasma sLRP, a peripheral sink for brain Aβ. In WT mice, the extract induced liver, but not brain, LRP and NEP and decreased plasma and brain Aβ, indicating that increase in liver LRP and sLRP occurring independent of Aβ concentration could result in clearance of Aβ. Selective down-regulation of liver LRP, but not NEP, abrogated the therapeutic effects of the extract. The remarkable therapeutic effect of W. somnifera mediated through up-regulation of liver LRP indicates that targeting the periphery offers a unique mechanism for Aβ clearance and reverses the behavioral deficits and pathology seen in Alzheimer's disease models. 相似文献
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