Development of Z-scheme bimetallic tungstate-supported nitrogen deficient g-C3N4 heterojunction for the treatment of refractory pharmaceutical pollutants

The binary BMT/ND-GCN-based heterostructure photocatalyst for pharmaceutical industry wastewater treatment.

An artificial synaptic transistor using an α-In2Se3 van der Waals ferroelectric channel for pattern recognition

Despite being widely investigated for their memristive behavior, ferroelectrics are barely studied as channel materials in field-effect transistor (FET) configurations. In this work, we use multilayer α-In₂Se₃ to realize a ferroelectric channel semiconductor FET, i.e., FeS-FET, whose gate-triggered and polarization-induced resistive switching is then exploited to mimic an artificial synapse. The FeS-FET exhibits key signatures of a synapse such as excitatory and inhibitory postsynaptic current, potentiation/depression, and paired pulsed facilitation. Multiple stable conductance states obtained by tuning the device are then used as synaptic weights to demonstrate pattern recognition by invoking a hidden layer perceptron model. Detailed artificial neural network (ANN) simulations are performed on binary scale MNIST data digits, invoking 784 input (28 × 28 pixels) and 10 output neurons which are used in the training of 42 000 MNIST data digits. By updating the synaptic weights with conductance weight values on 18 000 digits, we achieved a successful recognition rate of 93% on the testing data. Introduction of 0.10 variance of noise pixels results in an accuracy of more than 70% showing the strong fault-tolerant nature of the conductance states. These synaptic functionalities, learning rules, and device to system-level simulation results based on α-In₂Se₃ could facilitate the development of more complex neuromorphic hardware systems based on FeS-FETs.

Despite being widely investigated for their memristive behavior, ferroelectrics are barely studied as channel materials in field-effect transistor (FET) configurations.

Sunlight-assisted degradation of textile pollutants and phytotoxicity evaluation using mesoporous ZnO/g-C3N4 catalyst

Accessibility of adequate safe and fresh water for human consumption is one of the most significant issues throughout the world and extensive research is being undertaken to resolve it. Nanotechnology is now an outstanding medium for water treatment and remediation from microorganisms and organic dyes, as compared to conventional treatment methods. For this task graphitic carbon nitride (g-C3N4) is a potential nanomaterial for environmental remediation, but its photogenerated charge carrier recombination rate restricts its use in practical applications. Hence, in the current study, we used a simple one-step calcination method to synthesize various ratios of ZnO/g-C3N4 binary nanocomposites. The band gap of g-C3N4 is 2.70 eV, but it is shifted to 2.60 eV by the 0.75 : 1 ZnO/g-C3N4 binary nanocomposite. Moreover, phase structure, morphology, thermal stability, oxidation state, elemental analysis, and surface area were evaluated using XRD, SEM, TEM, TGA, XPS, and BET analysis. The optimal ZnO loading content was determined and the mechanism of enhanced photocatalytic activity was studied in detail. The photocatalytic efficiency of the best catalyst was employed for the degradation of textile effluent followed by phytotoxicity evaluation using methylene blue (MB), and rhodamine B (RhB) as a model substrate was tested. Furthermore, the textile effluent treatment analysis discovered that the 75 mg concentration of 0.75 : 1 ZnO/g-C3N4 catalyst degraded up to 80% within 120 min and significantly reduced the concentrations of different physico-chemical parameters of textile effluents. These treated effluents have no phytotoxic effects on fenugreek plants, according to a pot study. It was found that the mesoporous 0.75 : 1 ZnO/g-C3N4 catalyst can be used as an effective and low-cost technique for the degradation of azo dyes in textile wastewaters.

Molecular Targeting of HuR Oncoprotein Suppresses MITF and Induces Apoptosis in Melanoma Cells

Simple Summary

The human antigen R (HuR) protein regulates the expression of hundreds of proteins in a cell that support tumor growth, drug resistance, and metastases. HuR is overexpressed in several human cancers, including melanoma, and is a molecular target for cancer therapy. Our study objective, therefore, was to develop HuR-targeted therapy for melanoma. We identified that HuR regulates the microphthalmia-associated transcription factor (MITF) that has been implicated in both intrinsic and acquired drug resistance in melanoma and is a putative therapeutic target in melanoma. Using a gene therapeutic approach, we demonstrated silencing of HuR reduced MITF protein expression and inhibited the growth of melanoma cells but not normal melanocytes. However, combining HuR-targeted therapy with a small molecule MEK inhibitor suppressed MITF and produced a synergistic antitumor activity against melanoma cells. Our study results demonstrate that HuR is a promising target for melanoma treatment and offers new combinatorial treatment strategies for overriding MITF-mediated drug resistance.

Abstract

Background: Treatment of metastatic melanoma possesses challenges due to drug resistance and metastases. Recent advances in targeted therapy and immunotherapy have shown clinical benefits in melanoma patients with increased survival. However, a subset of patients who initially respond to targeted therapy relapse and succumb to the disease. Therefore, efforts to identify new therapeutic targets are underway. Due to its role in stabilizing several oncoproteins’ mRNA, the human antigen R (HuR) has been shown as a promising molecular target for cancer therapy. However, little is known about its potential role in melanoma treatment. Methods: In this study, we tested the impact of siRNA-mediated gene silencing of HuR in human melanoma (MeWo, A375) and normal melanocyte cells in vitro. Cells were treated with HuR siRNA encapsulated in a lipid nanoparticle (NP) either alone or in combination with MEK inhibitor (U0126) and subjected to cell viability, cell-cycle, apoptosis, Western blotting, and cell migration and invasion assays. Cells that were untreated or treated with control siRNA-NP (C-NP) were included as controls. Results: HuR-NP treatment significantly reduced the expression of HuR and HuR-regulated oncoproteins, induced G1 cell cycle arrest, activated apoptosis signaling cascade, and mitigated melanoma cells’ aggressiveness while sparing normal melanocytes. Furthermore, we demonstrated that HuR-NP treatment significantly reduced the expression of the microphthalmia-associated transcription factor (MITF) in both MeWo and MITF-overexpressing MeWo cells (p < 0.05). Finally, combining HuR-NP with U0126 resulted in synergistic antitumor activity against MeWo cells (p < 0.01). Conclusion: HuR-NP exhibited antitumor activity in melanoma cells independent of their oncogenic B-RAF mutational status. Additionally, combinatorial therapy incorporating MEK inhibitor holds promise in overriding MITF-mediated drug resistance in melanoma.

Electrical transport and gas sensing characteristics of dielectrophoretically aligned MBE grown catalyst free InAs nanowires

In this report, the precise alignment of catalyst free InAs nanowires (NWs) on pre-patterned Au microelectrodes by dielectrophoresis (DEP) technique for gas sensing applications is presented. The catalyst free InAs NWs have been grown on Si (111) substrate by molecular beam epitaxy (MBE) technique. The effect of dispersing solvents, electrode geometries and gaps, magnitude, frequency and duration of applied voltage etc, has been studied for aligning the InAs NWs by DEP technique. Current-voltage (I-V) measurements on the aligned NWs show linear behavior at room temperature (300 K), which changes to nonlinear at lower temperatures and higher voltages. The nonlinearity at lower temperatures and higher voltages is well explained by a space charge limited current contribution, which further gives a quantitative estimation of free charge carriers and trap density. The DEP aligned NWs exhibit good sensing response upon exposure to 10 ppm NO₂ gas.

Tuning the band gap of hybrid lead free defect perovskite nano crystals for solar cell applications

In recent reports, combinations of lead free organic inorganic halide perovskites have shown significant advances in solar cell devices.

IL-24 modulates the high mobility group (HMG) A1/miR222 /AKT signaling in lung cancer cells

Interleukin (IL)-24, a novel tumor suppressor/cytokine exhibits antitumor activity against a broad-spectrum of human cancer cells. In a recent study, we showed that IL-24 inhibited AKT in lung cancer cells. However, the molecular mechanism of AKT inhibition by IL-24 remains elusive.The high mobility group (HMG) A1 a member of the non-histone chromosomal proteins and commonly referred to as architectural transcription factor, regulates transcription of various genes involved in cell growth and survival. Overexpression of HMGA1 has been shown to be associated with tumor progression and metastasis in several cancers, including human lung cancer. A recent study demonstrated that HMGA1 activates AKT function by reducing the activity of the protein phosphatase, phosphatase 2A subunit B (PPP2R2A) via the oncogenic micro (mi) RNA-222. Based on this report we hypothesized that IL-24-mediated AKT inhibition involved the HMGA1/miR-222 axis.To test our hypothesis, in the present study we used a H1299 lung cancer cell line that expressed exogenous human IL-24 when induced with doxycycline (DOX). Induction of IL-24 expression in the tumor cells markedly reduced HMGA1 mRNA and protein levels. Using a mechanistic approach, we found that IL-24 reduced miR-222-3p and -5p levels, as determined by qRT-PCR. Associated with HMGA1 and miR-222 inhibition was a marked increase in PPP2R2A, with a concomitant decrease in phosphorylated AKTT308/S473 expression. SiRNA-mediated knockdown of HMGA1 in combination with IL-24 significantly reduced AKT T308/S473 protein expression and greatly reduced cell migration and invasion compared with individual treatments. Further combination of IL-24 and a miR-222-3p inhibitor significantly increased PPP2R2A expression.Our results demonstrate for the first time that IL-24 inhibits AKT via regulating the HMGA1/miR-222 signaling node in human lung cancer cells and acts as an effective tumor suppressor. Thus, a therapy combining IL-24 with HMGA1 siRNA or miR-222-3p inhibitor should present effective treatment of lung cancer.

Recent Advances in Nanoparticle-Based Cancer Drug and Gene Delivery

Effective and safe delivery of anticancer agents is among the major challenges in cancer therapy. The majority of anticancer agents are toxic to normal cells, have poor bioavailability, and lack in vivo stability. Recent advancements in nanotechnology provide safe and efficient drug delivery systems for successful delivery of anticancer agents via nanoparticles. The physicochemical and functional properties of the nanoparticle vary for each of these anticancer agents, including chemotherapeutics, nucleic acid-based therapeutics, small molecule inhibitors, and photodynamic agents. The characteristics of the anticancer agents influence the design and development of nanoparticle carriers. This review focuses on strategies of nanoparticle-based drug delivery for various anticancer agents. Recent advancements in the field are also highlighted, with suitable examples from our own research efforts and from the literature.

Chemodrug delivery using integrin-targeted PLGA-Chitosan nanoparticle for lung cancer therapy

In this study, we report the efficacy of RGD (arginine-glycine-aspartic acid) peptide-modified polylactic acid-co-glycolic acid (PLGA)-Chitosan nanoparticle (CSNP) for integrin α_vβ₃ receptor targeted paclitaxel (PTX) delivery in lung cancer cells and its impact on normal cells. RGD peptide-modified chitosan was synthesized and then coated onto PTX-PLGA nanoparticles prepared by emulsion-solvent evaporation. PTX-PLGA-CSNP-RGD displayed favorable physicochemical properties for a targeted drug delivery system. The PTX-PLGA-CSNP-RGD system showed increased uptake via integrin receptor mediated endocytosis, triggered enhanced apoptosis, and induced G2/M cell cycle arrest and more overall cytotoxicity than its non-targeted counterpart in cancer cells. PTX-PLGA-CSNP-RGD showed less toxicity in lung fibroblasts than in cancer cells, may be attributed to low drug sensitivity, nevertheless the study invited close attention to their transient overexpression of integrin α_vβ₃ and cautioned against corresponding uptake of toxic drugs, if any at all. Whereas, normal human bronchial epithelial (NHBE) cells with poor integrin α_vβ₃ expression showed negligible toxicity to PTX-PLGA-CSNP-RGD, at equivalent drug concentrations used in cancer cells. Further, the nanoparticle demonstrated its capacity in targeted delivery of Cisplatin (CDDP), a drug having physicochemical properties different to PTX. Taken together, our study demonstrates that PLGA-CSNP-RGD is a promising nanoplatform for integrin targeted chemotherapeutic delivery to lung cancer.

HuR-targeted small molecule inhibitor exhibits cytotoxicity towards human lung cancer cells

Human antigen (Hu) R is an RNA-binding protein whose overexpression in human cancer correlates with aggressive disease, drug resistance, and poor prognosis. HuR inhibition has profound anticancer activity. Pharmacologic inhibitors can overcome the limitations of genetic inhibition. In this study, we examined the antitumor activity of CMLD-2, a small-molecule inhibitor directed against HuR, using non-small cell lung cancer (NSCLC) as a model. CMLD-2 efficacy was tested in vitro using H1299, A549, HCC827, and H1975 NSCLC cells and MRC-9 and CCD-16 normal human fibroblasts. Treatment of NSCLC cells with CMLD-2 produced dose-dependent cytotoxicity, caused a G1 phase cell-cycle arrest and induced apoptosis. CMLD-2 decreased HuR mRNA and the mRNAs of HuR-regulated proteins (Bcl2 and p27) in tumor cells. Additionally, reduction in the expression of HuR, Bcl2, cyclin E, and Bcl-XL with increased expression of Bax and p27 in CMLD-2-treated NSCLC cells were observed. CMLD-2-treated normal cells, HuR-regulated mRNAs and proteins albeit showed some reduction were less compared to tumor cells. Finally, CMLD-2 treatment resulted in greater mitochondrial perturbation, activation of caspase-9 and -3 and cleavage of PARP in tumor cells compared to normal cells. Our proof-of concept study results demonstrate CMLD-2 represents a promising HuR-targeted therapeutic class that with further development could lead to advanced preclinical studied and ultimately for lung cancer treatment.

Simulation of an Armoured Vehicle for Blast Loading

Occupant safety in an armoured vehicle is of paramount importance. Most serious threat to armoured vehicles comes in the form of explosion of buried charge or an improvised explosive device. The use of numerical methods in the validation process of light armoured vehicles reduces the number of prototypes required and decreases the design time. This paper elucidates the process by which one such validation using numerical methods was done. The process of finite element method used for simulation of blast is a prominent method of numerical method of simulation. The finite element model (FEM) process starts with discretisation. By discretisation or meshing, Shell (Quad/Tria) and solid (Tetra/Hexa) elements are generated. The FEM thus created is provided with relevant material model / properties and loading and boundary conditions. The loading conditions are adopted from STANAG 4569 Level II standards. Local deformation, global displacement, stresses and time history of displacement of particular areas of interest are obtained as results. Comparison results include the effect of with and without thermal softening under blast. Based on the results and comparison, suggestions regarding re-engineering the vehicle are presented.

Tumor-targeted Nanoparticle Delivery of HuR siRNA Inhibits Lung Tumor Growth In Vitro and In Vivo By Disrupting the Oncogenic Activity of the RNA-binding Protein HuR

Selective downregulation of the human antigen R (HuR) protein by siRNA may provide a powerful approach for treating lung cancer. To this end, we investigated the efficacy of transferrin receptor-targeted liposomal nanoparticle-based HuR siRNA (HuR-TfNP) therapy and compared with control siRNA (C)-TfNP therapy both, in vitro and in vivo using lung cancer models. In vitro studies showed HuR-TfNP, but not C-TfNP, efficiently downregulated HuR and HuR-regulated proteins in A549, and HCC827 lung cancer cells, resulting in reduced cell viability, inhibition of cell migration and invasion, and induction of G₁ cell-cycle arrest culminating in apoptosis. However, HuR-TfNP activity in normal MRC-9 lung fibroblasts was negligible. In vivo biodistribution study demonstrated that fluorescently labeled HuR-siRNA or ICG dye-loaded TfNP localized in tumor tissues. Efficacy studies showed intratumoral or intravenous administration of HuR-TfNP significantly inhibited A549 (>55% inhibition) and HCC827 (>45% inhibition) subcutaneous tumor growth compared with C-TfNP. Furthermore, HuR-TfNP treatment reduced HuR, Ki67, and CD31 expression and increased caspase-9 and PARP cleavage and TUNEL-positive staining indicative of apoptotic cell death in tumor tissues compared with C-TfNP treatment. The antitumor activity of HuR-TfNP was also observed in an A549-luc lung metastatic model, as significantly fewer tumor nodules (9.5 ± 3.1; P < 0.001; 88% inhibition) were observed in HuR-TfNP-treated group compared with the C-TfNP-treated group (77.7 ± 20.1). Significant reduction in HuR, Ki67, and CD31 expression was also observed in the tumor tissues of HuR-TfNP-treatment compared with C-TfNP treatment. Our findings highlight HuR-TfNP as a promising nanotherapeutic system for lung cancer treatment. Mol Cancer Ther; 16(8); 1470-86. ©2017 AACR.

Polymeric Nanoparticle-Mediated Gene Delivery for Lung Cancer Treatment

In recent years, researchers have focused on targeted gene therapy for lung cancer, using nanoparticle carriers to overcome the limitations of conventional treatment methods. The main goal of targeted gene therapy is to develop more efficient therapeutic strategies by improving the bioavailability, stability, and target specificity of gene therapeutics and to reduce off-target effects. Polymer-based nanoparticles, an alternative to lipid and inorganic nanoparticles, efficiently carry nucleic acid therapeutics and are stable in vivo. Receptor-targeted delivery is a promising approach that can limit non-specific gene delivery and can be achieved by modifying the polymer nanoparticle surface with specific receptor ligands or antibodies. This review highlights the recent developments in gene delivery using synthetic and natural polymer-based nucleic acid carriers for lung cancer treatment. Various nanoparticle systems based on polymers and polymer combinations are discussed. Further, examples of targeting ligands or moieties used in targeted, polymer-based gene delivery to lung cancer are reviewed.

Nanoparticles for siRNA-Based Gene Silencing in Tumor Therapy

Gene silencing through RNA interference (RNAi) has emerged as a potential strategy in manipulating cancer causing genes by complementary base-pairing mechanism. Small interfering RNA (siRNA) is an important RNAi tool that has found significant application in cancer therapy. However due to lack of stability, poor cellular uptake and high probability of loss-of-function due to degradation, siRNA therapeutic strategies seek safe and efficient delivery vehicles for in vivo applications. The current review discusses various nanoparticle systems currently used for siRNA delivery for cancer therapy, with emphasis on liposome based gene delivery systems. The discussion also includes various methods availed to improve nanoparticle based-siRNA delivery with target specificity and superior efficiency. Further this review describes challenges and perspectives on the development of safe and efficient nanoparticle based-siRNA-delivery systems for cancer therapy.

Abstract 3738: IL-24 modulates the high mobility group (HMG) A1/miR222 /AKT signaling in lung cancer cells

Background: High mobility group A1 (HMGA1), a member of the non-histone chromosomal proteins and commonly referred to as architectural transcription factor, regulates transcription of various genes involved in cell growth and survival. Overexpression of HMGA1 has been shown to be associated with tumor progression and metastasis in several cancers, including human lung cancer. A recent study demonstrated that HMGA1 activates AKT function by reducing the activity of the protein phosphatase, phosphatase 2A subunitB (PPPR2A) via the oncogenic micro (mi) RNA-222. We demonstrated that interleukin (IL)-24, a novel tumor suppressor/cytokine, inhibited AKT in lung cancer cells. However, the molecular mechanism of AKT inhibition by IL-24 remains elusive.

Aim: To determine the molecular mechanism of IL-24-mediated AKT inhibition involved the HMGA1/miR-222 axis.

Methods: Human H1299 lung tumor cell line was stably transfected with a tetracycline-inducible plasmid vector carrying the IL-24. After the induced expression of IL-24 protein, expression levels of HMGA1 and its downstream molecular mechanisms were analyzed at the RNA and protein levels in lung cancer cell lines. The inhibitory effect of IL-24 on HMG A1/miR222 /AKT axis in the lung cancer cells is determined by RT-qPCR, western blot, reporter assay, and immunocytochemistry. Mechanistic approaches on overexpression and knockdown of HMGA1 and or miR-222 were utilized and the consequences of its inhibition/overexpression were analyzed on HMGA1/miR222 /AKT signaling axis and in vitro migration and invasion.

Results: Upon induction of IL-24 expression in the H1299 lung tumor cells, we observed a marked reduction in HMGA1protein and mRNA levels. Using a mechanistic approach, we found that IL-24 reduced miR-222-3p and -5p levels, as determined by qRT-PCR. Associated with HMGA1 and miR-222 inhibition was a marked increase in PPP2R2A, with a concomitant decrease in phosphorylated AKTT308/S473 expression. SiRNA-mediated knockdown of HMGA1in combination with IL-24 significantly reduced AKT T308/S473 protein expression and greatly reduced cell migration and invasion compared with individual treatments. Further combination of IL-24 and a miR-222-3p inhibitor significantly increased PPP2R2A expression.

Conclusion: Our results demonstrate for the first time that IL-24 inhibits AKT via regulating the HMGA1/miR-222 signaling node in human lung cancer cells and acts as an effective tumor suppressor. HMGA1 should present a novel target for the effective treatment of lung cancer.

Citation Format: Janani Panneerselvam, Akhil Srivastava, Ranganayaki Muralidharan, Qi Wang, Wei Zheng, Lichao Zhao, Allshine Chen, Yan Zhao, Anupama Munshi, Rajagopal Ramesh. IL-24 modulates the high mobility group (HMG) A1/miR222 /AKT signaling in lung cancer cells. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3738.

Microstructural and Compositional Characterisation of Electronic Materials

<p class="p1"> </p><p class="p2"><span class="s1"> </span>Microstructural and compositional characterisation of electronic materials in support of the development of GaAs, GaN, and GaSb based multilayer device structures is described. Electron microscopy techniques employing nanometer and sub-nanometer scale imaging capability of structure and chemistry have been widely used to characterise various aspects of electronic and optoelectronic device structures such as InGaAs quantum dots, InGaAs pseudomorphic (pHEMT), and metamorphic (mHEMT) layers and the ohmic metallisation of GaAs and GaN high electron mobility transistors, nichrome thin film resistors, GaN heteroepitaxy on sapphire and silicon substrates, as well as InAs and GaN nanowires. They also established convergent beam electron diffraction techniques for determination of lattice distortions in III-V compound semiconductors, EBSD for crystalline misorientation studies of GaN epilayers and high-angle annular dark field techniques coupled with digital image analysis for the mapping of composition and strain in the nanometric layered structures. Also, <em>in-situ </em>SEM experiments were performed on ohmic metallisation of pHEMT device structures. The established electron microscopy expertise for electronic materials with demonstrated examples is presented.</p>

Folate receptor-targeted nanoparticle delivery of HuR-RNAi suppresses lung cancer cell proliferation and migration

BACKGROUND

Human antigen R (HuR) is an RNA binding protein that is overexpressed in many human cancers, including lung cancer, and has been shown to regulate the expression of several oncoproteins. Further, HuR overexpression in cancer cells has been associated with poor-prognosis and therapy resistance. Therefore, we hypothesized that targeted inhibition of HuR in cancer cells should suppress several HuR-regulated oncoproteins resulting in an effective anticancer efficacy. To test our hypothesis, in the present study we investigated the efficacy of folate receptor-α (FRA)-targeted DOTAP:Cholesterol lipid nanoparticles carrying HuR siRNA (HuR-FNP) against human lung cancer cells.

RESULTS

The therapeutic efficacy of HuR-FNP was tested in FRA overexpressing human H1299 lung cancer cell line and compared to normal lung fibroblast (CCD16) cells that had low to no FRA expression. Physico-chemical characterization studies showed HuR-FNP particle size was 303.3 nm in diameter and had a positive surface charge (+4.3 mV). Gel retardation and serum stability assays showed that the FNPs were efficiently protected siRNA from rapid degradation. FNP uptake was significantly higher in H1299 cells compared to CCD16 cells indicating a receptor-dose effect. The results of competitive inhibition studies in H1299 cells demonstrated that HuR-FNPs were efficiently internalized via FRA-mediated endocytosis. Biologic studies demonstrated HuR-FNP but not C-FNP (control siRNA) induced G1 phase cell-cycle arrest and apoptosis in H1299 cells resulting in significant growth inhibition. Further, HuR-FNP exhibited significantly higher cytotoxicity against H1299 cells than it did against CCD16 cells. The reduction in H1299 cell viability was correlated with a marked decrease in HuR mRNA and protein expression. Further, reduced expression of HuR-regulated oncoproteins (cyclin D1, cyclin E, and Bcl-2) and increased p27 tumor suppressor protein were observed in HuR-FNP-treated H1299 cells but not in C-FNP-treated cells. Finally, cell migration was significantly inhibited in HuR-FNP-treated H1299 cells compared to C-FNP.

CONCLUSIONS

Our results demonstrate that HuR is a molecular target for lung cancer therapy and its suppression using HuR-FNP produced significant therapeutic efficacy in vitro.

Phosphorylation of interleukin (IL)-24 is required for mediating its anti-cancer activity

Interleukin (IL)-24 is a tumor suppressor/cytokine gene that undergoes post-translational modifications (PTMs). Glycosylation and ubiquitination are important for IL-24 protein stabilization and degradation respectively. Little is known about IL-24 protein phosphorylation and its role in IL-24-mediated anti-tumor activities. In this study we conducted molecular studies to determine whether IL-24 phosphorylation is important for IL-24-mediated anti-cancer activity.

Human H1299 lung tumor cell line that was stably transfected with a doxycycline (DOX)-inducible (Tet-on) plasmid vector carrying the cDNA of IL-24-wild-type (IL-24^wt) or IL-24 with all five phosphorylation sites replaced (IL-24^mt) was used in the present study. Inhibition of tumor cell proliferation, cell migration and invasion, and induction of G2/M cell cycle arrest was observed in DOX-induced IL-24^wt-expressing cells but not in IL-24^mt-expressing cells. Secretion of IL-24^mt protein was greatly reduced compared to IL-24^wt protein. Further, IL-24^wt and IL-24^mt proteins markedly differed in their subcellular organelle localization. IL-24^wt but not IL-24^mt inhibited the AKT/mTOR signaling pathway. SiRNA-mediated AKT knockdown and overexpression of myristolyated AKT protein confirmed that IL-24^wt but not IL-24^mt mediated its anti-cancer activity by inhibiting the AKT signaling pathway.

Our results demonstrate that IL-24 phosphorylation is required for inhibiting the AKT/mTOR signaling pathway and exerting its anti-cancer activities.

Tailoring the magnetic and magnetoelectric properties of rare earth orthoferrites for room temperature applications

The M(T) curve shows negative magnetization value for samples containing Er ions. The dielectric constant value does not show any anomaly around the magnetic transition temperature. The temperature at which maximum MDE effect observed corresponds to dielectric loss maxima.

Tumor-targeted and pH-controlled delivery of doxorubicin using gold nanorods for lung cancer therapy

Background

In lung cancer, the efficacy of conventional chemotherapy is limited due to poor drug accumulation in tumors and nonspecific cytotoxicity. Resolving these issues will increase therapeutic efficacy.

Methods

GNR-Dox-Tf-NPs (gold nanorod-doxorubicin-transferrin-nanoparticles) were prepared by different chemical approaches. The efficacy of these nanoparticles was carried out by cell viability in lung cancer and primary coronary artery smooth muscle cells. The receptor-mediated endocytosis studies were done with human transferrin and desferrioxamine preincubation. The GNR-Dox-Tf nanoparticles induced apoptosis, and DNA damage studies were done by Western blot, H2AX foci, and comet assay.

Results

We developed and tested a gold nanorod-based multifunctional nanoparticle system (GNR-Dox-Tf-NP) that carries Dox conjugated to a pH-sensitive linker and is targeted to the transferrin receptor overexpressed in human lung cancer (A549, HCC827) cells. GNR-Dox-Tf-NP underwent physicochemical characterization, specificity assays, tumor uptake studies, and hyperspectral imaging. Biological studies demonstrated that transferrin receptor-mediated uptake of the GNR-Dox-Tf-NP by A549 and HCC827 cells produced increased DNA damage, apoptosis, and cell killing compared with nontargeted GNR-Dox-NP. GNR-Dox-Tf-NP-mediated cytotoxicity was greater (48% A549, 46% HCC827) than GNR-Dox-NP-mediated cytotoxicity (36% A549, 39% HCC827). Further, GNR-Dox-Tf-NP markedly reduced cytotoxicity in normal human coronary artery smooth muscle cells compared with free Dox.

Conclusion

Thus, GNR-Dox-Tf nanoparticles can selectively target and deliver Dox to lung tumor cells and alleviate free Dox-mediated toxicity to normal cells.

Abstract 3306: The RNA-binding protein HuR radiosensitizes human TNBC cells by modulating the cellular response to DNA damage and oxidative stress

The RNA-binding protein human antigen R (HuR) associates with U-/AU-rich mRNAs encoding proteins that control cell proliferation, metabolism and the stress response. HuR is overexpressed in several human cancers and its overexpression is associated with poor prognosis and resistance to therapy. While the role of HuR in drug resistance has been studied, its contribution to radiation resistance has not been examined. Therefore, we investigated the role of HuR in radiation resistance of triple negative breast cancer (TNBC) cells: MDA-MB-231, MDA-MB-468 and Hs578t. Reduction of HuR expression using small interfering (si) RNA decreased cell proliferation and sensitized TNBC cells to ionizing radiation. Clonogenic assays indicated that silencing HuR suppressed the clonogenic survival of all three TNBC cell lines with survival at 2 Gy (SF2) reduced from 59%, 49%, 65% in control cells to 40%, 33%, and 46% in siHuR-treated MDA-MB-231, MDA-MB-468 and Hs578t cells, respectively. To delineate the underlying mechanism of radiosensitization and to identify candidate mRNAs showing altered levels after silencing HuR, we undertook a ribonomic approach. First, since ionizing radiation enhances the production of reactive oxygen species (ROS), causing DNA damage, we investigated the possible involvement of ROS in siHuR-mediated radiosensitization. ROS production in control or HuR-silenced cells treated with or without radiation was measured using the fluorescent dye 2′-7′-Dichlorodihydrofluorescein diacetate (DCFDA). Radiation significantly increased ROS generation in HuR knockdown cells compared to control cells. To further test the involvement of ROS in radiosensitivity, control and HuR-silenced cells were pre-treated with N-Acetyl-L- cysteine (NAC), an ROS scavenger, prior to radiation. The presence of NAC completely prevented radiation sensitivity and ROS production, indicating the involvement of ROS in HuR-mediated radiation sensitivity. Second, we directly tested the involvement of the DNA damage response (DDR) pathway in radiosensitivity after silencing HuR by evaluating the number of γ-H2AX foci (a common indicator of DNA damage) in control and HuR-silenced cells following irradiation. Our results showed that the number of γ-H2AX foci was significantly greater in HuR-silenced cells than in control cells at 1 h, 2 h and 24 h after irradiation. The persistence of γ-H2AX foci suggests that radiosensitization by HuR silencing involves inhibition of the repair of damaged DNA. This hypothesis was supported by the comet assay, which showed that HuR-silenced cells had larger and longer-lasting tails than control cells, in keeping with the higher levels of DNA damage seen after silencing HuR. Our studies indicate that radiosensitization upon HuR knockdown is linked to suppression of the cellular response to genotoxic and oxidative damage.

Citation Format: Meghna Mehta, James Griffith, Kanthesh Basalingappa, Anish Babu, Narsireddy Amreddy, Ranganayaki Muralidharan, Myriam Gorospe, Terence Herman, Wei-Qun Ding, Rajagopal Ramesh, Anupama Munshi. The RNA-binding protein HuR radiosensitizes human TNBC cells by modulating the cellular response to DNA damage and oxidative stress. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3306. doi:10.1158/1538-7445.AM2015-3306

Abstract 3943: siRNA-mediated HuR silencing sensitizes triple-negative breast cancer cells to radiation therapy

HuR is a ubiquitously expressed member of the Elav/Hu family of RNA-binding proteins which can associate with mRNAs containing AU-rich elements in their 3′-untranslated regions. It is predominantly a nuclear protein that translocates to the cytoplasm in response to stress signals and stabilizes mRNAs encoding proteins implicated in cell proliferation, angiogenesis, apoptosis, and stress response. Studies examining HuR expression in human cancers indicated that elevated cytoplasmic HuR expression is associated with a high histologic grade, large tumor size, and poor survival of patients with cancer, leading to the hypothesis that cytoplasmic HuR abundance could be a prognostic marker in cancer patients. It has been reported that altering the subcellular distribution of HuR leads to a decrease in mRNA stability and increases tamoxifen responsiveness in breast cancer cells. As the role of HuR in radiation resistance has not been previously evaluated, we designed this study to determine the role of HuR in mediating radiation response of human breast cancer cells. Subcellular fractionation studies in a panel of breast cancer cells [triple negative (MDA-MB-231, MDA-MB-468 and Hs578t), luminal (MCF-7), and normal mammary epithelial (MCF-10a)] demonstrated elevated cytoplasmic levels of HuR in the more aggressive triple negative breast cancer cells (TNBC) compared to the normal mammary and the luminal cells. TNBCs also had high expression of HuR mRNA and total protein as observed by quantitative (Q) RT-PCR and western blot analysis. To test if high expression of HuR contributed to the radiation resistance of TNBCs, HuR was silenced and cells were exposed to various doses of radiation. Clonogenic assays indicated that silencing HuR enhanced tumor cell radiosensitivity in MDA-MB-231, MDA-MB-468 and Hs578t cells, with the survival fraction at 2Gy declining from 59%, 49%, 65% in control (scrambled siRNA-transfected cells) to 40%, 33%, 46% in HuR-silenced cells, respectively. MCF-7 and MCF-10a cells were not radiosensitized upon HuR silencing. Since HuR plays a central role in cancer it is possible that multiple pathways and mechanisms are affected by HuR knockdown and could contribute to the observed radiosensitivity. Molecular studies suggested that HuR silencing in combination with radiation modulated the expression of several genes involved in cell survival, cell cycle and DNA repair in MDA-MB-231 cells. The involvement of the DNA repair pathway following treatment with siHuR was assessed using γ-H2AX foci as a marker. Our results show that a higher number of radiation-induced γ-H2AX foci are present in HuR-silenced MDA-MB-231 cells compared with control cells, suggesting a suppression of the double-strand DNA repair pathway. The persistence of γ-H2AX foci was not seen in the MCF-7 cells. We propose that HuR knockdown enhances the radioresponse of TNBC cells by inhibiting the repair of radiation-induced double-strand DNA breaks.

Citation Format: Kanthesh M. Basalingappa, Meghna Mehta, James N. Griffith, Ranganayaki Muralidharan, Myriam Gorospe, Rajagopal Ramesh, Anupama Munshi. siRNA-mediated HuR silencing sensitizes triple-negative breast cancer cells to radiation therapy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3943. doi:10.1158/1538-7445.AM2014-3943

Abstract 5418: Tumor-targeted nanoparticle delivery of HuR-RNAi suppresses lung cancer cell proliferation and cell migration

Objective. HuR is an mRNA-binding protein that specifically binds to AU rich (ARE) sites at the 3′end of the mRNA of several growth factors, cell-cycle regulators, and transcription-regulating proteins and transports the mRNA to the cytoplasm for protein translation. HuR overexpression has been demonstrated to be a poor prognostic marker in a spectrum of human cancers and correlate with chemotherapy resistance. On the basis of these reports we hypothesized HuR is a druggable target for cancer therapy and its inhibition will down-regulate multiple oncoproteins resulting in efficient tumor cell killing. To test our hypothesis, we developed and tested the efficacy of a nanoparticle (NP) containing HuR-specific siRNA and targeted towards folate receptor (Fr) overexpressing lung cancer cells in vitro.

Methods. Human lung cancer (H1299, A549) and normal fibroblast (MRC-9) cell lines were used in the present study. Folate receptor (Fr) overexpressing KB cell line was used as positive control. Tumor targeted nanoparticle was synthesized by mixing cationic lipid (DOTAP) with a neutral lipid (cholesterol) in equimolar ratio. The NPs thus formed were used to encapsulate fluorescently labeled siRNA for determining transfection efficiency; scrambled (control) siRNA or HuR-specific siRNA (100 nm) for efficacy studies. The control- and HuR-siRNA-containing NPs were subsequently decorated with DSPE-PEG5000-folate and labeled as C-FNP and HuR-FNP respectively. Transfection efficiency, NP specificity, cell viability, cell migration and HuR knock down studies were performed using standard laboratory assay protocols.

Results. HuR protein expression in H1299 and A549 was higher than in MRC-9 cell line. Folate receptor (Fr) expression from highest to lowest was in the following order KB&gt; H1299&gt;MRC9. Fr expression was not detected in A549 cells. Transfection efficiency study showed FNP uptake was highest in KB cells followed by H1299 cells with lowest uptake by A549 cells. Addition of exogenous folic acid resulted in reduced FNP uptake by H1299 cells demonstrating NP specificity towards Fr. Treatment of H1299 cells with HuR-FNP significantly reduced cell viability at 48h compared to C-FNP-treatment and correlated with a marked reduction in HuR mRNA and protein expression levels. Analysis for proteins whose mRNAs are targets for and regulated by HuR (Bcl2, Cyclin D1, HIF-1α) showed diminished expression in HuR-FNP-treated cells. Finally, cell migration was significantly inhibited in HuR-FNP-treated H1299 cells compared to C-FNP treatment.

Conclusions. Tumor-targeted nanoparticle delivery of HuR-RNAi in lung cancer cells selectively inhibited HuR and HuR-regulated oncoproteins resulting in diminished cell proliferation and cell migration in vitro.

Acknowledgement. This study was funded by a grant (R01CA167516-01) from the National Cancer Institute.

Citation Format: Ranganayaki Muralidharan, Anish Babu, Kanthesh Basalingappa, Anupama Munshi, Rajagopal Ramesh. Tumor-targeted nanoparticle delivery of HuR-RNAi suppresses lung cancer cell proliferation and cell migration. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5418. doi:10.1158/1538-7445.AM2014-5418

Chitosan coated polylactic acid nanoparticle-mediated combinatorial delivery of cisplatin and siRNA/Plasmid DNA chemosensitizes cisplatin-resistant human ovarian cancer cells

Development of resistance toward anticancer drugs results in ineffective therapy leading to increased mortality. Therefore, overriding resistance and restoring sensitivity to anticancer drugs will improve treatment efficacy and reduce mortality. While numerous mechanisms for drug resistance in cancer have previously been demonstrated, recent studies implicate a role for proteasome and the autophagy regulatory protein P62/SQSTM1 (P62) in contributing to drug resistance. Specifically, reduction in the expression of the β5 subunit of the proteasome and/or enhanced P62 protein expression is known to contribute to cancer drug resistance such as cisplatin (CDDP) in ovarian cancer cells. Therefore, we hypothesized that restoration of β5 expression and/or suppression of P62 protein expression in CDDP-resistant ovarian cancer cells will lead to restoration of sensitivity to CDDP and enhanced cell killing. To test our hypothesis we developed a biodegradable multifunctional nanoparticle (MNP) system that codelivered P62siRNA, β5 plasmid DNA, and CDDP and tested its efficacy in CDDP resistant 2008/C13 ovarian cancer cells. MNP consisted of CDDP loaded polylactic acid nanoparticle as inner core and cationic chitosan (CS) consisting of ionically linked P62siRNA (siP62) and/or β5 expressing plasmid DNA (pβ5) as the outer layer. The MNPs were spherical in shape with a hydrodynamic diameter in the range of 280-350 nm, and demonstrated encapsulation efficiencies of 82% and 78.5% for CDDP and siRNA respectively. MNPs efficiently protected the siRNA and showed superior serum stability compared to naked siRNA as measured by gel retardation and spectrophotometry assays. The MNPs successfully delivered siP62 and pβ5 to cause P62 knockdown and restoration of β5 expression in 2008/C13 cells. Combined delivery of siP62, pβ5, and CDDP using the MNPs resulted in a marked reduction in the IC50 value of CDDP in 2008/C13 cells from 125 ± 1.3 μM to 98 ± 0.6 μM (P < 0.05; 21.6% reduction) when compared to the reduction in the IC50 of CDDP observed in cells that had only siP62 delivered (IC50 = 106 ± 1.1 μM; P < 0.05; 15.2% reduction) or pβ5 delivered (IC50 = 115 ± 2.8 μM; 8% reduction) via MNPs. Finally, our studies showed that the CDDP resistance index in 2008/C13 cells was reduced from 4.62 for free CDDP to 3.62 for MNP treatment. In conclusion our study results demonstrated the efficacy of our MNP in overcoming CDDP resistance in ovarian cancer cells.

Abstract 5249: Functional importance of IL-24 phosphorylation in regulating molecular signaling pathways associated with cancer cell survival and metastasis

Purpose of the Study: Interleukin (IL)-24 is a novel tumor suppressor/cytokine that has demonstrated potent anti-cancer activities against human tumors in both, preclinical and clinical studies. However, the importance of IL-24 phosphorylation for its anti-tumor effects remains in question. Therefore the present study was designed to identify the functional importance of IL-24 phosphorylation in mediating its anti-cancer activities.

Experimental Procedure: Human H1299 lung tumor cell line was stably transfected with a tetracycline-inducible plasmid vector carrying the IL-24-wild-type (IL-24wt) or -IL-24 with global knock-down of all five phosphorylation sites (IL-24mt) cDNA. Upon addition of doxycycline (Dox; 1ug/ml), cells were induced to express wt or mt IL-24 protein. The functional importance of IL-24 phosphorylation was determined by assessing the Akt/mTOR signaling pathway and the consequence of its inhibition on cell viability, cell migration, and invasion.

Results: Expression of IL-24wt but not IL-24mt resulted in inhibition of cell growth and reduced colony formation on soft-agar. Cell migration and invasion studies demonstrated that IL-24wt significantly suppressed the migration rate and invasion of tumor cells across matrigel compared to cells expressing IL-24mt. Confocal microscopy showed IL-24wt protein expression as punctate staining and present in the cytoplasm throughout the cell, whereas IL-24mt protein expression was mainly localized to the perinuclear space, endoplasmic reticulum (ER) and golgi. Reverse-phase protein array (RPPA) assay revealed differences in expression levels of Akt and its downstream targets between H1299 cells expressing IL-24wt and IL-24mt. Validation of RPPA data by Western blotting demonstrated expression of phosphorylated (p)-AKT and its downstream targets such as p-GSK-3β, p-mTOR, p-FOXO1, p-YAP1, and Cyclin D1 were markedly reduced with an increased expression of p27 and p-beta-catenin in H1299 cells expressing IL-24wt compared to H1299 cells expressing IL-24mt. Critical Akt/mTOR signaling pathways and their connected molecular transcriptional factors, which are important for cancer cell survival and metastasis were significantly suppressed in IL-24wt expressing H1299 cell lines thus reducing tumor survival and metastasis.

Conclusion: Our results demonstrate for the first time, phosphorylation of IL-24, is functionally important and required for mediating its anticancer activities via inhibiting the Akt/mTOR pathway. Additional molecular studies are underway to identify the specific phosphorylation site (s) required for the IL-24-mediated anticancer activities.

Citation Format: Janani Panneerselvam, Manish Shanker, Jiankang Jin, Cynthia Branch, Ranganayaki Muralidharan, Qi Wang, Anupama Munshi, Ramesh Rajagopal. Functional importance of IL-24 phosphorylation in regulating molecular signaling pathways associated with cancer cell survival and metastasis. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5249. doi:10.1158/1538-7445.AM2013-5249

Susac syndrome: clinical characteristics and treatment in 29 new cases

BACKGROUND AND PURPOSE

  There are few clinical studies on the attempted treatments and outcomes in patients with Susac syndrome (SS) (retinocochleocerebral vasculopathy).

METHODS

  A retrospective review was performed of all patients presenting with SS at the Mayo Clinic in Rochester, Minnesota, USA (1 January 1998-1 October 2011).

RESULTS

  There were 29 cases of SS (24 women, mean age at presentation, 35 years; range, 19-65; full triad of brain, eye, and ear involvement, n = 16; mean follow-up time, 29 months). Thirty CSF analyses were performed in 27 cases (mean protein 130 mg/dl, range 35-268; mean cell count 14, range 1-86). MRI of the brain showed corpus callosal involvement (79%), T2-weighted hyperintensities (93%), and gadolinium enhancement (50%). Average lowest modified Rankin Scale score was 2.5 (median 2, range 0-5). Most patients (93%) received immunosuppressive treatment, with a mean time to treatment of 2 months following symptomatic onset. Treatments included intravenous methylprednisolone or dexamethasone (n = 23), oral corticosteroids (n = 24), plasma exchange (PLEX) (n = 9), intravenous immunoglobulin (IVIg) (n = 15), cyclophosphamide (n = 6), mycophenolate mofetil (n = 5), azathioprine (n = 2), and rituximab (n = 1). Most patients also received an antiplatelet agent (n = 21). Improvement or stabilization was noted in eight of 11 cases treated with IVIg in the acute period (three experienced at least partial deterioration) and eight of nine cases of PLEX treatment (one lost to follow up).

CONCLUSIONS

  Susac syndrome may be severe, disabling, and protracted in some patients. PLEX may be an adjunct or alternative therapy for patients who do not experience symptomatic improvement following steroid treatment.

Enamel defects and salivary methylmalonate in methylmalonic acidemia

INTRODUCTION AND OBJECTIVE

To characterize enamel defects in patients with methylmalonic acidemia (MMA) and cobalamin (cbl) metabolic disorders and to examine salivary methylmalonate levels in MMA.

SUBJECTS AND METHODS

Teeth from patients (n = 32) were evaluated for enamel defects and compared with age- and gender-matched controls (n = 55). Complementation class (mut, cblA, cblB and cblC) and serum methylmalonate levels were examined. Primary teeth from two patients were examined by light and scanning electron microscopy and salivary methylmalonate levels from two patients were analyzed.

RESULTS

Enamel defects were significantly more prevalent per tooth in the affected group than the control group, across complementation types (P < 0.0001). The mut MMA subgroup had a significantly higher prevalence per individual of severe enamel defects than controls (P = 0.021), and those with enamel defects exhibited higher serum methylmalonate levels than those without (P = 0.017). Salivary methylmalonate levels were extremely elevated and were significantly higher than controls (P = 0.002). Primary teeth were free of enamel defects except for two cblC patients who exhibited severe enamel hypoplasia. One primary tooth from a cblC patient manifested markedly altered crystal microstructure.

CONCLUSION

Enamel anomalies represent a phenotypic manifestation of MMA and cbl metabolic disorders. These findings suggest an association between enamel developmental pathology and disordered metabolism.

Approach to a person recently diagnosed with diabetes

The physician who sees a newly diagnosed patient with diabetes can adequately fulfill his professional responsibilities by following a systematic approach to clinical diagnosis, investigations, appropriate treatment planning and involvement of the patient in is or her treatment through self-management education. Correct steps taken in the crucial initial period set the pace for optimum future management of this chronic disease.

Raman and AFM studies of swift heavy ion irradiated InGaAs/GaAs heterostructures

The effect of swift heavy ion (SHI) irradiation on InGaAs/GaAs heterostructures is studied using Raman spectroscopy and atomic force microscopy (AFM). The structures consist of molecular beam epitaxy (MBE) grown InGaAs layers on GaAs(001), having layer thicknesses of 12, 36, 60 and 96 nm. After irradiation, the GaAs type longitudinal optical (LO) mode blue shifted to higher frequency in thin samples and red shifted towards lower frequency in thick samples. These results are discussed invoking the penetration depth of the probe radiation (λ = 514.5 nm) in InGaAs. Deconvoluting the Raman spectra of thin samples indicates a compressive strain developed in the substrate, close to the interface upon irradiation. This modification and diffusion of indium across the interface results in an increase of strain and reduction of the defect densities in the InGaAs layer. The variations in FWHM of the Raman modes are discussed in detail. The surface morphology of these heterostructures has been studied by AFM before and after SHI irradiation. These studies, combined with Raman results, help to identify different relaxation regimes.

Sevoflurane for trans-sternal thymectomy in myasthenia gravis

Myasthenic gravis (MG) is an autoimmune disease associated with acetylcholine receptor deficiency. Patients with MG exhibit increased sensitivity to non-depolarising muscle relaxants. In an attempt to avoid neuromuscular blockers, we used sevoflurane in two myasthenic patients undergoing trans-sternal thymectomy. Inhalation of 8% sevoflurane in oxygen using vital capacity technique produced rapid, pleasant and smooth induction and provided good tracheal intubating conditions. In both patients anaesthesia was maintained with 1.5-2% end-tidal concentration of sevoflurane and nitrous oxide in oxygen without adjunctive neuromuscular blocking agents. There were minimal changes in cardiovascular variables and recovery was faster. It is suggested that sevoflurane may be the main anaesthetic for both induction and maintenance in myasthenic patients undergoing trans-sternal thymectomy.

Growth hormone therapy

Growth hormone therapy with rhGH (recombinant human growth hormone) has been recommended for treatment of GH deficient short stature in children, repeated hypoglycemias in infancy and early childhood due to GH deficiency, short stature accompanying chronic renal failure prior to renal transplantation and Turner's syndrome. It is now increasingly recommended to adults with GH deficiency following pituitary tumour surgery or irradiation or idiopathic hypopituitarism. There are other indications for its use where evidence for protein catabolism is very strong such as burns injury. The end points of GH therapy in children include achievement of desirable adult height or a growth rate velocity of < 2.5 cm/year. In adults GH deficiency, GH therapy is intended for improvement of general well being, body composition and metabolic markers of GH function.

Temple Ecology and Cognitive Development: A Report from South India

The impact of growing up in the vicinity of Hindu temples on cognitive development was studied in the southern part of India. Enrolled in Grades 1 and 4, the participating children (N-281) were drawn from three kinds of ecology, i.e., families intimately associated with temple, families that are religious but not so intimately associated with temple, and families in non-temple areas, using a cross-sectional design. NCERT School Readiness Scale and Das-Naglieri Cognitive Assessment System were used to assess their cognitive development. Children associated with temples emerged to be more cognitively competent than other two groups of children on both points of schooling. Sex differences and their interaction with ecology were not significant for most of the measures. Results point to the role of temple institutions in shaping development of children byproviding rich and variegated ecology.

Drug induced endocrine problems

Drug induced effects on the various endocrine and metabolic processes constitute a very common differential diagnostic possibility in investigating endocrine disorders. Knowledge of drug-effect is of paramount importance to avoid unnecessary and expensive investigations and treatment. Since most of the effects are type A effects and hence predictable, reduction of dose or modification of therapy is sufficient to reverse the adverse effects.