A Novel, Potent, Small Molecule AKT Inhibitor Exhibits Efficacy against Lung Cancer Cells In Vitro

Saketh S. Dinavahi,Rajagopalan Prasanna,Sriram Dharmarajan,Yogeeswari Perumal,Srikant Viswanadha 대한암학회 2015 Cancer Research and Treatment Vol.47 No.4

Purpose Anomalies of Akt regulation, including overexpression in lung cancer, impart resistance toconventional chemotherapy and radiation, thereby implicating this kinase as a therapeuticintervention point. A novel scaffold of Akt inhibitors was developed through virtual screeningof chemical databases available at Birla Institute of Technology and Science, Pilani, Hyderabad,based on docking studies using Maestro. A benzothienopyrimidine derivative (BIA-6)was identified as a potential lead molecule that inhibited Akt1 enzyme activity with an IC50of 256 nM. Materials and MethodsBIA-6 was tested for in vitro Akt1 inhibition using a fluorescence resonance energy transferkit. Anti-proliferative activity was tested in NCI-H460, A549, NCI-H1975, and NCI-H2170cell lines. The effect of the compound on p-Akt (S473) was estimated. ResultsBIA-6 allosterically caused a dose dependent reduction of growth of cell lines with a halfmaximal growth inhibition (GI50) range of 0.49 !M to 6.6 !M. Cell cycle analysis indicatedthat BIA-6 caused a G1 phase arrest at < 100 nM but led to apoptosis at higher doses. BIA-6 also exhibited synergism with standard chemotherapeutic agents. ConclusionBIA-6 is a novel, allosteric Akt inhibitor with potent anti-cancer activity in lung cancer celllines, that effectively blocks the phosphoinositide-3 kinase/Akt pathway with a high marginselectivity towards normal cells.

Study on the ferromagnetism in Co and N doped ZnO thin films

S. Ramasubramanian,R. Thangavel,M. Rajagopalan,A. Thamizhavel,K. Asokan,D. Kanjilal,J. Kumar 한국물리학회 2013 Current Applied Physics Vol.13 No.8

Present investigation reports the structural, optical and magnetic properties of co-doping of Co and N ions in ZnO samples, prepared by two distinct methods. In the first method, samples are synthesized by Solegel technique in which the Co and N are co-doped simultaneously during the growth process itself. In the second case, N ions are implanted in the Co doped ZnO thin films grown by Pulsed Laser Deposition (PLD). Structural studies showed that the nitrogen implantation on Co doped ZnO samples developed compressive stress in the films. X-ray photoelectron spectroscopy confirmed the doping of Co and N in ZnO matrix. In the Resonant Raman scattering multiple LO phonons up to fifth order are observed in the (Co, N) co-doped ZnO. Photoluminescence spectra showed that there is reduction in the bandgap due to the presence of Co in the lattice and also the presence of Zn vacancies in the films. All samples showed ferromagnetic behavior at room temperature. The magnetic moment observed in the implanted films is found to be varied with the different dosages of the implanted N ions. First principle calculations have been carried out to study the possible magnetic interaction in the co-doped system. Present study shows that the ferromagnetic interaction is due to the hybridization between N 2p and Co 3d states in the (Co, N) co-doped ZnO and is very sensitive to the geometrical configurations of dopants and the vacancy in the ZnO host lattice.

정현파 형상 노즐 제트의 유동특성에 관한 실험적 연구

김학림,S.Rajagopalan,이상준 한국가시화정보학회 2009 한국가시화정보학회지 Vol.7 No.2

The turbulent jet with two sinusoidal nozzle exit configurations of in-phase and 180o out-ofphase was investigated experimentally using a smoke-wire method and a hot-wire anemometry. Mean velocity and turbulence intensity were measured at several downstream locations under ReD = 5000. For the case of in-phase nozzle configuration, the length of potential core exhibits negligible difference with respect to the transverse locations (0, λ/4 and λ/2), similar to those of a plane jet. On the other hand, a maximum difference of 30% in the potential-core length occurs for the 180o out-of-phase configuration. The spatial distributions of turbulence intensities also shows significant difference for the nozzle of 180˚ out-of-phase, whereas non-symmetric distribution is observed in the near-exit region(x/D = 1) for the inphase sinusoidal nozzle jet. Compared to normal slit jet, the sinusoidal nozzle jets seem to suppress the velocity deficit as the flow goes downstream. The sinusoidal nozzle jet was formed to decrease turbulent intensity dramatically. The flow visualization results show that the flow characteristics of the sinusoidal nozzle jet are quite different from those of the normal slit plane jet. The turbulent jet with two sinusoidal nozzle exit configurations of in-phase and 180o out-ofphase was investigated experimentally using a smoke-wire method and a hot-wire anemometry. Mean velocity and turbulence intensity were measured at several downstream locations under ReD = 5000. For the case of in-phase nozzle configuration, the length of potential core exhibits negligible difference with respect to the transverse locations (0, λ/4 and λ/2), similar to those of a plane jet. On the other hand, a maximum difference of 30% in the potential-core length occurs for the 180o out-of-phase configuration. The spatial distributions of turbulence intensities also shows significant difference for the nozzle of 180˚ out-of-phase, whereas non-symmetric distribution is observed in the near-exit region(x/D = 1) for the inphase sinusoidal nozzle jet. Compared to normal slit jet, the sinusoidal nozzle jets seem to suppress the velocity deficit as the flow goes downstream. The sinusoidal nozzle jet was formed to decrease turbulent intensity dramatically. The flow visualization results show that the flow characteristics of the sinusoidal nozzle jet are quite different from those of the normal slit plane jet.

정현파 형상의 노즐을 갖는 제트 유동에 대한 실험적 연구

김학림(Hak Lim Kim),S. Rajagopalan,이상준(Sang Joon Lee) 한국가시화정보학회 2008 한국가시화정보학회 학술발표대회 논문집 Vol.- No.2

In this study the flow pattern of a jet with two sinusoidal nozzle exit configurations such as inphase and 180o out-of-phase was investigated using a smoke-wire method and a hot-wire anemometry. Mean velocity and turbulence intensity were measured at several downstream locations (0, λ/4 and λ/2) under U<SUB>j</SUB> (exit velocity) of 3 m/s (Re<SUB>D</SUB> = 5000). For the case of in-phase, the potential core lengths exhibited negligible difference with respect to these transverse locations, similar to those of a plane jet. On the other hand, a maximum difference of 30% in the potential core lengths was appeared for the 180o out-of-phase configuration. Significant differences in the distribution of turbulence intensities were also noticed for the out-of-phase nozzle configuration. Flow visualization images seem to suggest the presence of non-symmetric vortices that can yield the differences between the nozzles configurations.

정현파 형상 노즐 제트의 유동특성에 관한 실험적 연구

김학림(Hak Lim Kim),S. Rajagopalan,이상준(Sang Joon Lee) 한국가시화정보학회 2010 한국가시화정보학회지 Vol.7 No.2

Two turbulent jet with different sinusoidal nozzle exit configurations of in-phase and 180° out-of-phase were investigated experimentally using a smoke-wire method and a hot-wire anemometry. Mean velocity and turbulence intensity were measured at several downstream locations under Re<SUB>D</SUB> = 5000. For the case of in-phase nozzle configuration, the length of potential core exhibits negligible difference with respect to the transverse locations (0, λ/4 and λ/2), similar to that of a plane jet. On the other hand, a maximum difference of 30% in the potential-core length occurs for the 180° out-of-phase configuration. The spatial distributions of turbulence intensities also show significant difference for the nozzle of 180° out-of-phase, whereas non-symmetric distribution is observed in the near-exit region(x/D = 1) for the inphase sinusoidal nozzle jet. Compared to a slit plane jet, the sinusoidal nozzle jets seem to suppress the velocity deficit as the flow goes downstream. The sinusoidal nozzle jet was found to decrease turbulent intensity dramatically. The flow visualization results show that the flow characteristics of the sinusoidal nozzle jet are quite different from those of the slit plane jet.

Facile synthesis of graphene/N-doped carbon nanowire composites as an effective electrocatalyst for the oxygen reduction reaction

Babu, K.F.,Rajagopalan, B.,Chung, J.S.,Choi, W.M. Pergamon Press ; Elsevier Science Ltd 2015 International journal of hydrogen energy Vol.40 No.21

A novel metal-free electrocatalyst for the oxygen reduction reaction (ORR) is one of the most important issues in fuel cells. Here, we report a facile method to synthesize reduced graphene oxide (rGO) decorated with nitrogen-doped carbon nanowires (rGO-CN) as an electrocatalyst for ORR. After the polymerization of polpyrrole nanowires on the rGO surface (rGO-PPy), the carbonization of rGO-PPy at 800 <SUP>o</SUP>C affords a unique nanostructured product by the integration of rGO sheets and the N-doped carbon nanowires with high nitrogen content. The morphology of rGO-CN is confirmed by TEM analysis and the chemical composition and interaction of the prepared samples are analyzed by XPS and FT-IR analysis. The electrocatalytic activity of rGO-CN toward ORR is also evaluated by the cyclic voltammetry. It is found that the rGO-CN electrode shows superior electrocatalytic performance toward ORR, compared to rGO and rGO-PPy, which demonstrates the promising potential of rGO-CN as a carbon-based, metal-free electrocatalyst for enhancing the electrocatalytic property towards ORR.

Optical and Electrical Properties of Bulk-grown Ternary In_xGa_(1−x)As

Y. K. Yeo,A. C. Bergstrom,R. L. Hengehold,J. W. Wei,S. Guha,L. P. Gonzalez,G. Rajagopalan,류미이 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.58 No.51

Bulk ternary In_xGa_(1−x)As polycrystals were grown using the vertical Bridgman technique. The optical and electrical properties of these bulk In_xGa_(1−x)As were investigated as a function of indium mole fraction from 0.75 to 0.99 by using photoluminescence (PL) and Hall-effect measurements. All samples showed good infrared transmission. A free exciton (FX) transition peak was observed from all bulk In_xGa_(1−x)As samples, and it redshifted from 0.568 to 0.412 eV as the indium mole fraction increased from 0.75 to 0.99. Bandgaps estimated from the indium compositionand temperature-dependent FX peaks generally followed the theoretically calculated bandgaps. All as-grown In_xGa_(1−x)As samples showed n-type conductivity. Although all bulk In_xGa_(1−x)As samples showed good optical transmissions and PL transitions, as well as high carrier mobilitites, they exhibited some random compositional fluctuations across the sample area.