02685nas a2200265 4500008004100000022001400041245012000055210006900175260007200244300001200316490000700328520175700335653000802092653001702100653002402117653001302141100002102154700002202175700001802197700002102215700002002236700001902256700001602275856012802291 2008 eng d a0022-074400aImaging the interaction between dengue 2 virus and human blood platelets using atomic force and electron microscopy0 aImaging the interaction between dengue 2 virus and human blood p aGREAT CLARENDON ST, OXFORD OX2 6DP, ENGLANDbOXFORD UNIV PRESScJUN a113-1180 v573 a

Thrombocytopenia is frequently associated with dengue virus infection. Host factors such as anti-platelet immunopathogenic processes have been implicated in the origin of dengue-associated thrombocytopenia but the role of dengue virus in directly interacting with platelets and altering their hemostatic property remains incompletely understood. In the present study, we examined the effect of dengue 2 virus on the morphology and physiological activation profile of normal human platelets using atomic force microscopy, electron microscopy and flowcytometry. Platelets obtained from healthy donors were exposed to a cell culture-adapted 10(4) LD(50) dengue 2 virus isolate in vitro and the subsequent effect on morphology and activation biology studied. Our results show that dengue 2 virus exposure at doses comparable to natural viremic states in human infections can activate platelets with an increase in P-selectin expression and fibrinogen-binding property. Atomic force, scanning and transmission electron microscopy also showed typical activation-related morphological changes such as altered platelet membrane architecture, degranulation, presence of filopodia and dilatation of the open canalicular system in the dengue 2 virus-exposed platelets but not in the controls. Importantly, Japanese encephalitis virus exposure at the same dose did not activate platelets or show any morphological changes. Our findings suggest that dengue 2 virus may directly interact with and activate platelets - an event that might be important in the origin of dengue-associated thrombocytopenia. Detailed molecular characterization of this effect might provide key knowledge toward better prophylaxis of the hemostatic complications of dengue disease.

10aAFM10adengue virus10aElectron microscopy10aplatelet1 aGhosh, Kanjaksha1 aGangodkar, Shobha1 aJain, Preksha1 aShetty, Shrimati1 aRamjee, Sandhya1 aPoddar, Pankaj1 aBasu, Atanu uhttp://library.ncl.res.in/content/imaging-interaction-between-dengue-2-virus-and-human-blood-platelets-using-atomic-force-002321nas a2200205 4500008004100000022001400041245014500055210006900200260007100269300001400340490000800354520149600362100002301858700002701881700002701908700002101935700002001956700001901976856012001995 2009 eng d a1932-744700aIn situ observation of antibiotic mediated concurrent growth of two distinct homogeneous populations of gold nanoparticles in solution phase0 aIn situ observation of antibiotic mediated concurrent growth of  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcMAR a3478-34860 v1133 a

We report the observation of the unusual nucleation and growth kinetics of gold nanoparticles synthesized in the presence of the antibiotic cephalexin using in situ static and dynamic light scattering in conjunction with in situ UV-vis absorption measurements and transmission electron microscopy. Following a brief latency period, two well-separated populations of gold nanoparticles, with average sizes of 1-2 nm versus several tens of nanometer, respectively, nucleate simultaneously. For either size regime, the total number of particles increased rapidly, while their mean size and relative frequency remained essentially constant over a growth period of 5 h. With increasing temperature, the morphology of the larger nanoparticles became increasingly spherical, as indicated by the noticeable blue shift of the plasmon frequency for these particles. The detailed morphology for either particle population was confirmed with TEM. To our knowledge, this is the first observation of simultaneous growth of two distinct populations of crystalline nanoparticles in the solution phase. The coupled growth of two distinct populations of nuclei, their tight control of size but rapid increase in overall numbers present novel and intriguing facets of this antibiotic-mediated solution-growth of gold nanoparticles. The size evolution of the Mie-frequency exhibits a noticeable blue shift as the temperature increases, correlating with the roundness of the particle/bimodal distribution.

1 aJagannathan, Ramya1 aParmar, Avanish, Singh1 aAdyanthaya, Suguna, D.1 aPrabhune, Asmita1 aMuschol, Martin1 aPoddar, Pankaj uhttp://library.ncl.res.in/content/situ-observation-antibiotic-mediated-concurrent-growth-two-distinct-homogeneous-001634nas a2200253 4500008004100000022001400041245008700055210006900142260010600211300001000317490000800327520071300335653002201048653001501070653002901085653001801114100003401132700002601166700001401192700001701206700001901223700002101242856011701263 2011 eng d a0038-109800aInvestigations of magnetic and dielectric properties of cupric oxide nanoparticles0 aInvestigations of magnetic and dielectric properties of cupric o aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcJAN a55-600 v1513 a

Cupric oxide nanoparticles of similar to 8-10 nm width and 40-45 nm length self assembled as large particles similar to 1-1 5 mu m have been investigated in the 10-325 K temperature range using magnetic and dielectric measurements In magnetic measurements a single broad peak at similar to 230 K in a zero field cooled sample has been observed Coercivity in magnetization measurements at 10 K suggests that the nanoparticles are core-shell type particles with an antiferromagnetic core and a ferromagnetic shell Dielectric measurements at various frequencies from 3 7 Hz to 949 kHz exhibit a sharp peak at 284 K followed by weak anomalies around 213 and 230 K (C) 2010 Elsevier Ltd All rights reserved

10aCuO nanoparticles10aDielectric10aFerroelectric transition10aFerromagnetic1 aBhalerao-Panajkar, Rohini, S.1 aShirolkar, Mandar, M.1 aDas, Raja1 aMaity, Tuhin1 aPoddar, Pankaj1 aKulkarni, S., K. uhttp://library.ncl.res.in/content/investigations-magnetic-and-dielectric-properties-cupric-oxide-nanoparticles-002685nas a2200193 4500008004100000022001400041245018200055210006900237260011000306300001400416490000600430520181900436100002302255700002302278700002302301700002502324700001902349856012302368 2013 eng d a2040-336400aIn situ synthesis and surface functionalization of gold nanoparticles with curcumin and their antioxidant properties: an experimental and density functional theory investigation0 aIn situ synthesis and surface functionalization of gold nanopart aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcDEC a1882-18930 v53 a

Curcumin ((1E,6E)-1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione) is an active component of turmeric; it is responsible for its characteristic yellow color and therapeutic potential, but its poor bioavailability remains a major challenge. In order to improve the bioavailability of curcumin, various approaches have been used. One of the possible approaches to increase the bioavailability of curcumin is its conjugation on the surface of metal nanoparticles. Therefore, in the present study, we report the binding of curcumin on the surface of gold nanoparticles (AuNPs). The AuNPs were synthesized by the direct reduction of HAuCl4 using curcumin in the aqueous phase, without the use of any other reducing agents. We found that curcumin acts both as a reducing and capping agent, stabilizing the gold sol for many months. Moreover, these curcumin-capped AuNPs also show good antioxidant activity which was confirmed by the DPPH (2,2-diphenyl-l-picrylhydrazyl) radical test. Thus, the surface functionalization of AuNPs with curcumin may pave a new way of using the curcuminoids towards possible drug delivery and therapeutics. Apart from the experimental study, a detailed quantum chemical calculation using density functional theory (DFT) has been performed, in order to investigate the formation of a complex of curcumin with Au3+ ions in different possible conformational isomeric forms. Our theoretical calculations indicate the evidence of electron transfer from curcumin into the Au center and essentially indicate that as a consequence of complexation, Au3+ ions are reduced to Au-0. Our theoretical results also propose that it is the breakage of intramolecular H-bonding that probably leads to the increased availability of curcumin in the presence of gold ions and water molecules.

1 aSingh, Dheeraj, K.1 aJagannathan, Ramya1 aKhandelwal, Puneet1 aAbraham, Priya, Mary1 aPoddar, Pankaj uhttp://library.ncl.res.in/content/situ-synthesis-and-surface-functionalization-gold-nanoparticles-curcumin-and-their-000668nas a2200181 4500008004100000245010900041210006900150260000800219300001400227490000700241100001900248700001400267700002100281700001800302700001900320700002700339856012000366 2014 eng d00aInterchain relay of antiferromagnetic ordering in 1D Co(II) coordination polymers via pi-pi interactions0 aInterchain relay of antiferromagnetic ordering in 1D CoII coordi cSEP a8523-85300 v161 aAhmad, Musheer1 aDas, Raja1 aMrozinski, Jerzy1 aBienko, Alina1 aPoddar, Pankaj1 aBharadwaj, Parimal, K. uhttp://library.ncl.res.in/content/interchain-relay-antiferromagnetic-ordering-1d-coii-coordination-polymers-pi-pi-001182nas a2200157 4500008004100000022001400041245015000055210006900205260007100274300001600345490000800361520049100369100001400860700001900874856013100893 2014 eng d a1932-744700aIonic control on the morphology of ytterbium manganese oxide nanorods and nanoplates in a surfactant-free synthesis and their magnetic properties0 aIonic control on the morphology of ytterbium manganese oxide nan a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUN a13268-132750 v1183 a

Here, we report the synthesis of multiferroic, single-crystalline ID YbMnO3 in nanoregime. By using ionic chemistry without the use of surfactant or template, we demonstrate control synthesis of one- and two-dimensional nanoparticles of YbMnO3. Magnetic properties of YbMnO3 show influence of morphology. Detailed alternating current (ac) and direct current (dc) magnetic study shows ferromagnetic interaction of Mn3+ and Yb3+ moments in nanorods of YbMnO3 below similar to 35 K.

1 aDas, Raja1 aPoddar, Pankaj uhttp://library.ncl.res.in/content/ionic-control-morphology-ytterbium-manganese-oxide-nanorods-and-nanoplates-surfactant-free-001803nas a2200217 4500008004100000022001400041245010000055210006900155260011000224300001400334490000800348520093200356100001801288700002301306700002701329700002701356700003401383700001901417700002501436856012401461 2016 eng d a0003-265400aImmobilization of multivalent glycoprobes on gold surfaces for sensing proteins and macrophages0 aImmobilization of multivalent glycoprobes on gold surfaces for s aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcFEB a2250-22580 v1413 a

The multivalent display of carbohydrates on the cell surface provides cooperative binding to improve the specific biological events. In addition to multivalency, the spatial arrangement and orientation of sugars with respect to external stimuli also trigger carbohydrate-protein interactions. Herein, we report a non-covalent host-guest strategy to immobilize heptavalent glyco-beta-cyclodextrin on gold-coated glass slides to study multivalent carbohydrate-protein interactions. We have found that the localization of sugar entities on surfaces using beta-cyclodextrin (beta-CD) chemistry increased the avidity of carbohydrate-protein and carbohydrate-macrophage interactions compared to monovalent-beta-CD sugar coated surfaces. This platform is expected to be a promising tool to amplify the avidity of sugar-mediated interactions on surfaces and contribute to the development of next generation bio-medical products.

1 aGade, Madhuri1 aKhandelwal, Puneet1 aSangabathuni, Sivakoti1 aBavireddi, Harikrishna1 aMurthy, Raghavendra, Vasudeva1 aPoddar, Pankaj1 aKikkeri, Raghavendra uhttp://library.ncl.res.in/content/immobilization-multivalent-glycoprobes-gold-surfaces-sensing-proteins-and-macrophages01597nas a2200229 4500008004100000022001400041245008100055210006900136260000800205300000800213490000700221520089300228653001501121653001901136653001001155653001901165653001601184653001901200100002101219700001901240856010801259 2023 eng d a0250-470700aInvestigating the ferrimagnetic behaviour of trigonal 3C Fe7S8 nanoparticles0 aInvestigating the ferrimagnetic behaviour of trigonal 3C Fe7S8 n cMAY a1080 v463 a

The magnetic properties of trigonal 3C Fe7S8 nanoparticles, synthesized via the thermal decomposition method, are investigated using temperature-dependent zero-field cooled (ZFC) and field-cooled (FC) magnetization (M-T) curves. The M-T data, recorded at 100 and 1000 Oe, reveal magnetic ordering with high Curie transition temperature (T-C > 300 K) in the specimen. The magnetization vs. applied magnetic field (M-H) data measured in the temperature range from 7 to 300 K show that the compound exhibits ferrimagnetic ordering. The values of coercivity (H-C), saturation magnetization (M-60 kOe) and remanent magnetization (M-R) appear to increase at lower measuring temperatures. As the result of increasing M-60 kOe at lower measuring temperatures, within the temperature range of 7 to 300 K, the maximum energy product (BHmax) has the highest value of 128 kG Oe at 7 K.

10aanisotropy10aenergy product10aFe7S810aferrimagnetism10aPyrrhotites10atrigonal phase1 aJyotsna, Shubhra1 aPoddar, Pankaj uhttp://library.ncl.res.in/content/investigating-ferrimagnetic-behaviour-trigonal-3c-fe7s8-nanoparticles