Rajendra Kumar Shukla

Nitric oxide and oxidative stress is associated with severity of diabetic retinopathy and retinal structural alterations

The aim of the study was to determine plasma nitric oxide (NO) and lipid peroxide (LPO) levels in diabetic retinopathy and its association with severity of disease.

Differential responses of Trans -Resveratrol on proliferation of neural progenitor cells and aged rat hippocampal neurogenesis

The plethora of literature has supported the potential benefits of Resveratrol (RV) as a life-extending as well as an anticancer compound. However, these two functional discrepancies resulted at different concentration ranges. Likewise, the role of Resveratrol on adult neurogenesis still remains controversial and less understood despite its well documented health benefits. To gather insight into the biological effects of RV on neurogenesis, we evaluated the possible effects of the compound on the proliferation and survival of neural progenitor cells (NPCs) in culture, and in the hippocampus of aged rats. Resveratrol exerted biphasic effects on NPCs; low concentrations (10 μM) stimulated cell proliferation mediated by increased phosphorylation of extracellular signal-regulated kinases (ERKs) and p38 kinases, whereas high concentrations (>20 μM) exhibited inhibitory effects. Administration of Resveratrol (20 mg/kg body weight) to adult rats significantly increased the number of newly generated cells in the hippocampus, with upregulation of p-CREB and SIRT1 proteins implicated in neuronal survival and lifespan extension respectively. We have successfully demonstrated that Resveratrol exhibits dose dependent discrepancies and at a lower concentration can have a positive impact on the proliferation, survival of NPCs and aged rat hippocampal neurogenesis implicating its potential as a candidate for restorative therapies against age related disorders.

Density and viscosity of tetrabutyl ammonium hydrogen sulphate and tetrabutyl ammonium chloride salts in aqueous and methanolic solution at 303 K

Density and viscosity of tetrabutyl ammonium hydrogen sulphate and tetrabutyl ammonium chloride in water as well as in methanol have been measured at 303.15 K. Different equations proposed by Einstein, Vand, Moulik and Jones–Dole for viscosity have been applied to the experimental results. An attempt has also been made to study the solute–solute and solute–solvent interactions involved in the system and the effect of anion on cationic surfactant. Molar volumes obtained from Einstein and Vand equations are very close to each other.

Modelling supply chain coordination in fuzzy environment

For allocating the components or services to trading partner, it would be significant to analyse level of coordination in their supply chain. For improving overall supply chain performance, an integrated approach of analytic hierarchy process (AHP) and technique for order preference by similarity to ideal solution (TOPSIS) in fuzzy environment are used. This paper presents how fuzzy analytic hierarchy process and fuzzy technique for order preference by similarity to ideal solution can be integrated for a more consistent evaluation and prioritisation of trading partner based on identified coordination criteria. Questionnaire survey is used to collect data from auto industries on factors reported in literature review. Based on factor analysis of survey data and further experts opinion four coordination criteria namely joint decision-making, information sharing, use of information technology tools and resource sharing determined are used to develop model. A case study of an Indian manufacturing company is described to illustrate the application of the proposed method. Fuzzy AHP is used to calculate relative weights of each coordination criterion and then partners are ranked based on closeness coefficient, calculated for each partner by using fuzzy TOPSIS.

PI3K/Akt/GSK3β induced CREB activation ameliorates arsenic mediated alterations in NMDA receptors and associated signaling in rat hippocampus: Neuroprotective role of curcumin

HIGHLIGHTSProtective role of curcumin in arsenic induced NMDA receptor alterations investigated.Sodium arsenite decreased expression of BDNF, pAkt, pErk ½, pGSK3&bgr; and pCREB.Curcumin protected sodium arsenite induced changes via PI3/Akt/MAPK pathway in hippocampus.Impaired cognitive deficits by sodium arsenite in rats also recovered by curcumin. ABSTRACT Protective efficacy of curcumin in arsenic induced NMDA receptor dysfunctions and PI3K/Akt/ GSK3&bgr; signalling in hippocampus has been investigated in vivo and in vitro. Exposure to sodium arsenite (in vivo – 20mg/kg, body weight p.o. for 28 days; in vitro – 10&mgr;M for 24h) and curcumin (in vivo – 100mg/kg body weight p.o. for 28 days; in vitro – 20&mgr;M for 24h) was carried out alone or simultaneously. Treatment with curcumin ameliorated sodium arsenite induced alterations in the levels of NMDA receptors, its receptor subunits and synaptic proteins ‐ pCaMKII&agr;, PSD‐95 and SynGAP both in vivo and in vitro. Decreased levels of BDNF, pAkt, pERK1/2, pGSK3&bgr; and pCREB on sodium arsenite exposure were also protected by curcumin. Curcumin was found to decrease sodium arsenite induced changes in hippocampus by modulating PI3K/Akt/GSK3&bgr; neuronal survival pathway, known to regulate various cellular events. Treatment of hippocampal cultures with pharmacological inhibitors for ERK1/2, GSK3&bgr; and Akt individually inhibited levels of CREB and proteins associated with PI3K/Akt/GSK3&bgr; pathway. Simultaneous treatment with curcumin was found to improve sodium arsenite induced learning and memory deficits in rats assessed by water maze and Y‐maze. The results provide evidence that curcumin exercises its neuroprotective effect involving PI3K/Akt pathway which may affect NMDA receptors and downstream signalling through TrK&bgr; and BDNF in arsenic induced cognitive deficits in hippocampus.

Photoconduction in amorphous thin films of Se90Sb10-xAgx glassy alloys

ABSTRACT The present paper reports the steady state photoconductivity and photosensitivity response of thermally evaporated amorphous thin films of Se90Sb10-xAgx(x = 2, 4, 6, 8, 10). Temperature dependence of dark conductivity is studied and activation energy is calculated for different samples. Temperature dependence of photoconductivity is also studied at different intensities. From temperature dependence of photoconductivity activation energy is computed at different intensities which are found to vary from 0.26 to 0.47 eV. Intensity dependence of photoconductivity has also been studied at different temperatures. These curves are plotted on logarithmic scale and found to be straight lines which show that photoconductivity follows a power law with intensity. Composition dependence of dark conductivity, activation energy of DC conduction and photosensitivity show that these parameters are highly. composition dependent and show a discontinuity at a particular composition when Ag concentration becomes 6 at. %. This is explained in terms of transition from floppy state to mechanically stabilized state at this composition.

Modelling supply chain coordination for performance improvement using analytical network process-based approach

In order to improve coordination in the supply chain, the selection of a supply chain coordination mechanism plays an important role. Due to the multi-dimensional nature of a supply chain problem, the selection of the right supply chain coordination mechanisms (SCCMs) in a given situation remains a difficult and most challenging task for supply chain managers. In this paper, an attempt has been made first to explore various issues pertaining to the selection and implementation of SCCMs and finally to create an analytical network process (ANP) based framework to help supply chain managers to take appropriate steps in the selection of SCCMs in a given situation. The framework presented in this paper summarises the role of market responsiveness, process integration, risk, requirement and flexibility for supply chain performance. The paper explores the relationship among cost, flexibility, quality, service level and lead time to prioritise coordination mechanisms of supply chain for Indian manufacturing companies. The paper concludes with the justification of the framework, which analyses and prioritises the alternatives using ANP to improve coordination in supply chain.