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41.
Eight cholesterol based cationic lipids differing in the headgroup have been synthesized based on the ether linkage between the cationic headgroup and the cholesterol backbone. All the lipids formed stable suspensions in water. Transfection efficacies were examined in the absence and presence of serum using their optimized liposomal (lipid:DOPE) formulations. Our results showed that the transfection activities depend on the nature of the headgroup. Lipid bearing 4-N,N′-dimethylaminopyridine (DMAP) as headgroup showed the maximum transfection efficacy in the presence of serum. Importantly, the optimized formulation for this cationic lipid does not require DOPE, which is being used by most commercially available formulations. Cytotoxicity studies showed that the introduction of the positive charge decreases the cell viability of the cationic lipid formulations. Gel electrophoresis and Ethidium bromide exclusion assay revealed the different DNA binding abilities of formulations depending upon the headgroup of the cholesteryl lipid. 相似文献
42.
Neil A. Koorbanally Neil R. Crouch Avinash Harilal Bavani Pillay Dulcie A. Mulholland 《Biochemical Systematics and Ecology》2006
We report on the first phytochemical investigation of a member of the African genus Resnova (Hyacinthoideae: Hyacinthaceae). From the dichloromethane extract of the bulbs of both Resnova humifusa and Eucomis montana (Hyacinthoideae: Hyacinthaceae) a novel 3-benzyl-4-chromanone homoisoflavonoid, 5,6-dimethoxy-7-hydroxy-3-(4′-hydroxybenzyl)-4-chromanone, was isolated. A further 11 known homoisoflavonoids were also identified, the 12 in total presenting a clear biosynthetic sequence. Eight of the 12 compounds found were common to both species. 相似文献
43.
Marc Kschonsak Lionel Rougé Christopher P. Arthur Ho Hoangdung Nidhi Patel Ingrid Kim Matthew C. Johnson Edward Kraft Alexis L. Rohou Avinash Gill Nadia Martinez-Martin Jian Payandeh Claudio Ciferri 《Cell》2021,184(5):1232-1244.e16
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44.
Avinash S. Punekar Tyson R. Shepherd Josefine Liljeruhm Anthony C. Forster Maria Selmer 《Nucleic acids research》2012,40(20):10507-10520
RlmM (YgdE) catalyzes the S-adenosyl methionine (AdoMet)-dependent 2′O methylation of C2498 in 23S ribosomal RNA (rRNA) of Escherichia coli. Previous experiments have shown that RlmM is active on 23S rRNA from an RlmM knockout strain but not on mature 50S subunits from the same strain. Here, we demonstrate RlmM methyltransferase (MTase) activity on in vitro transcribed 23S rRNA and its domain V. We have solved crystal structures of E. coli RlmM at 1.9 Å resolution and of an RlmM–AdoMet complex at 2.6 Å resolution. RlmM consists of an N-terminal THUMP domain and a C-terminal catalytic Rossmann-like fold MTase domain in a novel arrangement. The catalytic domain of RlmM is closely related to YiiB, TlyA and fibrillarins, with the second K of the catalytic tetrad KDKE shifted by two residues at the C-terminal end of a beta strand compared with most 2′O MTases. The AdoMet-binding site is open and shallow, suggesting that RNA substrate binding may be required to form a conformation needed for catalysis. A continuous surface of conserved positive charge indicates that RlmM uses one side of the two domains and the inter-domain linker to recognize its RNA substrate. 相似文献
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Venkat R. Gadhachanda Kyle J. Eastman Qiuping Wang Avinash S. Phadke Dharaben Patel Wengang Yang Christopher W. Marlor Milind Deshpande Mingjun Huang Jason A. Wiles 《Bioorganic & medicinal chemistry letters》2018,28(21):3463-3471
An unprecedented series of organometallic HCV (hepatitis C virus) NS5A (nonstructural 5A protein) replication complex inhibitors that incorporates a 1,1′-ferrocenediyl scaffold was explored. This scaffold introduces the elements of linear flexibility and non-planar topology that are unconventional for this class of inhibitors. Data from 2-D NMR spectroscopic analyses of these complexes in solution support an anti (unstacked) arrangement of the pharmacophoric groups. Several complexes demonstrate single-digit picomolar in vitro activity in an HCV genotype-1b replicon system. One complex to arise from this investigation (10a) exhibits exceptional picomolar activity against HCV genotype 1a and 1b replicons, low hepatocellular cytotoxicity, and good pharmacokinetic properties in rat. 相似文献
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Delcourt Alain Mathieu Gisèle Baji Halima Kimny Tan Flammang Michel Compagnon Paul-Louis 《Mycopathologia》1997,137(1):27-32
Six new polyazole derivatives from 2-(2,4-dichlorophenyl)-1,3-dioxolane were studied for their antifungal activity against pathogenic fungi for humans and animals. The antimycotic effect was largely restricted to the filamentous fungi with Aspergillus fumigatus and Scedosporium apiospermum being remarkably susceptible. Three compounds were as effective as the two references, ketoconazole and oxiconazole. The structure-activity relationships revealed that an oxime group combined with four chlorine atoms increased the antifungal properties of the chemical series.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
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Mahendra Rai Avinash P. Ingle Swapnil Gaikwad Felipe Hering Padovani Monica Alves 《Critical reviews in biotechnology》2016,36(5):777-787
Nanotechnology is the creation and use of materials and devices on the same scale as molecules and intracellular structures, typically less than 100?nm in size. It is an emerging science and has made its way into pharmaceuticals to significantly improve the delivery and efficacy of drugs in a number of therapeutic areas, due to development of various nanoparticle-based products. In recent years, there has been increasing evidence that nanotechnology can help to overcome many of the ocular diseases and hence researchers are keenly interested in this science. Nanomedicines offer promise as viable alternatives to conventional drops, gels or ointments to improve drug delivery to the eye. Because of their small size, they are well tolerated, thus preventing washout, increase bioavailability and also help in specific drug delivery. This review describes the application of nanotechnology in the control of human diseases with special emphasis on various eye and ocular surfaces diseases. 相似文献