A novel route for synthesis of temperature responsive nanoparticles

We report the preparation of responsive silica nanoparticles by reaction of epoxy modified silica with stimuli responsive poly (acrylic acid‐N‐isopropylacrylamide) (poly (AA‐co‐NIPAAm)). A series of copolymers of poly (AA‐co‐NIPAAm) were synthesized by a novel route, employing solid state condensation of polyacrylic acid and isopropyl amine in different feed ratios (44 mol %–100 mol % AA). The structure of the copolymers was characterized by FT‐IR, ¹H‐NMR. The lower critical solution temperature (LCST) was found to vary with the copolymer composition. The pH dependence of the LCST was also observed, and the copolymers exhibited a higher LCST at neutral pH than at acidic pH (4–5). Selected copolymers were used to prepare responsive core‐shell particles. Silica nanoparticles modified using glycidoxy propyl trimethoxy propyl silane were reacted with the responsive copolymer to form responsive core‐shell particles. The influence of reaction conditions on the modification of silica particles and reaction with responsive copolymers was investigated. The hydrodynamic behavior of the synthesized thermo responsive nanoparticles was also studied. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Development of Human Adrenocortical Adenoma (HAA1) Cell Line from Zona Reticularis

The human adrenal cortex is composed of distinct zones that are the main source of steroid hormone production. The mechanism of adrenocortical cell differentiation into several functionally organized populations with distinctive identities remains poorly understood. Human adrenal disease has been difficult to study, in part due to the absence of cultured cell lines that faithfully represent adrenal cell precursors in the early stages of transformation. Here, Human Adrenocortical Adenoma (HAA1) cell line derived from a patient’s macronodular adrenocortical hyperplasia and was treated with histone deacetylase inhibitors (HDACis) and gene expression was examined. We describe a patient-derived HAA1 cell line derived from the zona reticularis, the innermost zone of the adrenal cortex. The HAA1 cell line is unique in its ability to exit a latent state and respond with steroidogenic gene expression upon treatment with histone deacetylase inhibitors. The gene expression pattern of differentiated HAA1 cells partially recreates the roster of genes in the adrenal layer that they have been derived from. Gene ontology analysis of whole genome RNA-seq corroborated increased expression of steroidogenic genes upon HDAC inhibition. Surprisingly, HDACi treatment induced broad activation of the Tumor Necrosis Factor (TNF) alpha pathway. This novel cell line we developed will hopefully be instrumental in understanding the molecular and biochemical mechanisms controlling adrenocortical differentiation and steroidogenesis.     

Facile and Selective Carbonylation of Methane in Superacids

The carbonylation of CH₄ with carbon monoxide in superacids HF/SbF₅ or HSO₃F/SbF₅ leads to the exclusive and quantitative formation of the acylium ion ([CH₃CO]⁺[SbF₆]⁻) with the concomitant stoichiometric formation of SbF₃.     

Thermo‐rheological and functional properties of gamma‐irradiated wholewheat flour

The effects of different doses (0, 0.5, 1, 2.5, 5 and 10 kGy) of gamma irradiation on the thermal, rheological and functional properties of the wholewheat flour were evaluated. Water and oil absorption capacity of the flour increased from 85.92% to 91.44% and 1.10 to 1.91 g g^?1 of flour, respectively, with increase in irradiation dose. The dough development time decreased with dose from 4.0 to 3.0 min. The transition temperatures (T_o, T_p and T_c) decreased as the dose increased; enthalpy of gelatinisation (?H) decreased from 5.18 to 4.27 J g^?1 with dose. The flow behaviour showed a shear‐thinning behaviour, and the hysteresis area decreased with dose. The structural recovery decreased with dose. FTIR did not show formation of any new chemical groups.     

Bilateral adrenal cortical adenomas in primary hyperaldosteronism

Various 4-alkoxyphenylimidazolidin-2-ones were prepared from benzaldehydes via a Curtius rearrangement and were evaluated for their anticonvulsant activities.     

Secondary leukaemia characterised by monosomy 7 occurring post-autologous stem cell transplantation for AML

Secondary leukaemia has rarely been reported as a complication of autologous stem cell transplantation for AML. We report two cases of AML who presented with well-characterised cytogenetic abnormalities at presentation: t(8;21) and t(15;17) respectively, and who, after achieving complete morphological and cytogenetic remissions post-autograft, developed MDS/AML associated with monosomy 7. This secondary change is most frequently seen following alkylating agent therapy for solid tumours. The secondary leukaemia seen in our patients may thus be due to exposure of the residual stem cells to the alkylating agents used in the transplant conditioning.     

New polymer electrolyte for electrochemical application

A solid polymer electrolyte consisting of poly vinylpyrrolidone (PVP) and potassium iodide (KI) were developed, characterized for possible application in dye sensitized solar cell (DSSC) as an electrolyte. Complex impedance spectroscopy revealed the enhancement in electrical conductivity (σ) by salt doping and a conductivity maximum was obtained at 30 wt% KI concentration. Dielectric phenomena also support the σ data. Fourier transform infrared spectroscopy (FTIR) confirmed the composite nature of polymer electrolyte film. Using maximum electrical conductivity film we have fabricated a DSSC which shows 0.14% efficiency at 1 sun condition.