b-Sitosterol activates Fas signaling in human breast cancer cells

Abstract b-Sitosterol is the most abundant phytosterol. Phytosterols are enriched in legumes, oil seeds and unrefined plant oils as found in foods such as peanut butter, pistachios and sunflower seeds. b-Sitosterol inhibits the growth of several specific types of tumor cells in vitro and decreases the size and the extent of tumor metastases in vivo. The effects of bsitosterol on the extrinsic apoptotic programmed cell death pathway in human breast MCF-7 and MDA-MB-231 adenocarcinoma cells were examined, along with the extent of its incorporation into cellular membranes and its effects on cell growth, expression of Fas receptor pathway proteins, and caspase-8 activity. The results show that b-sitosterol exposure promotes its enrichment in transformed cell membranes and significantly inhibits tumor cell growth. Concurrently, Fas levels and caspase-8 activity are significantly increased. These actions are specific, as expression of other proteins of the Fas receptor pathway, including Fas ligand, FADD, p-FADD and caspase-8, remain unchanged. These findings support the hypothesis that b-sitosterol is an effective apoptosis-promoting agent and that incorporation of more phytosterols in the diet may serve a preventive measure for breast cancer

Target highlights in CASP14 : Analysis of models by structure providers

Abstract The biological and functional significance of selected CASP14 targets are described by the authors of the structures. The authors highlight the most relevant features of the target proteins and discuss how well these features were reproduced in the respective submitted predictions. The overall ability to predict three-dimensional structures of proteins has improved remarkably in CASP14, and many difficult targets were modelled with impressive accuracy. For the first time in the history of CASP, the experimentalists not only highlighted that computational models can accurately reproduce the most critical structural features observed in their targets, but also envisaged that models could serve as a guidance for further studies of biologically-relevant properties of proteins. This article is protected by copyright. All rights reserved.Peer reviewe

The Technique of Double Narration of R. K. Narayan's The Guide

Abstract R. K. Narayan is one of the three important Indian novelists i

Strain sensing with CNT Nanocomposites: Static, cyclic and dynamic electromechanical material characterization

Carbon Nanotube (CNT) nanocomposites are one of the most important candidates to realize innovative strain sensors for Structural Health Monitoring (SHM) applications. In this work, the effect of static and dynamic strain on the electromechanical properties of carbon nanotubes (CNTs) nanocomposites, is investigated. In particular the nanocomposite is formed by multi-walled CNTs (MWNTs) embedded in a PolymethylMethacrylate (PMMA) matrix. The MWNTs randomly distributed within the PMMA matrix form conductive paths. These paths modify they morphology when the material is strained. Consequently the overall material conductivity changes. Continuous monitoring is possible by correlating these electrical changes to the deformation level of the material. Different specimens are made by varying the MWNTs content (3%, 5%, 7%, weight fractions) and are tested under varying static, cyclic and dynamic loading conditions. It is found that the Gauge Factor (GF) and nanocomposite sensitivity to strain, are directly related to the MWNTs content. Nanocomposites with higher MWNTs percentages (7%) show the best behaviour with a smaller dispersion of the experimental data. This data reproducibility is comparable to that of conventional strain gauges. The proposed functional material has the beauty of being ultralight and flexible. Moreover this material design has the potential of being scalable in size allowing continuous monitoring of larger structural areas than commercial sensors. The results shown in this paper highlight that this nanocomposite is a great candidate for the realization of advanced sensing devices

Dietary Bioflavonoids Inhibit Escherichia Coli ATP Synthase in a Differential Manner

The aim of this study was to determine if the dietary benefits of bioflavonoids are linked to the inhibition of ATP synthase. We studied the inhibitory effect of 17 bioflavonoid compounds on purified F1 or membrane bound F1Fo E. coli ATP synthase. We found that the extent of inhibition by bioflavonoid compounds was variable. Morin, silymarin, baicalein, silibinin, rimantadin, amantidin, or, epicatechin resulted in complete inhibition. The most potent inhibitors on molar scale were morin (IC50∼0.07mM)\u3esilymarin (IC50∼0.11mM)\u3ebaicalein (IC50∼0.29mM)\u3esilibinin (IC50∼0.34mM)\u3erimantadin (IC50∼2.0mM)\u3eamantidin (IC50∼2.5mM)\u3eepicatechin (IC50∼4.0mM). Inhibition by hesperidin, chrysin, kaempferol, diosmin, apigenin, genistein, or rutin was partial in the range of 40-60% and inhibition by galangin, daidzein, or luteolin was insignificant. The main skeleton, size, shape, geometry, and position of functional groups on inhibitors played important role in the effective inhibition of ATP synthase. In all cases inhibition was found fully reversible and identical in both F1Fo membrane preparations and isolated purified F1. ATPase and growth assays suggested that the bioflavonoid compounds used in this study inhibited F1-ATPase as well as ATP synthesis nearly equally, which signifies a link between the beneficial effects of dietary bioflavonoids and their inhibitory action on ATP synthase

Exploiting location and contextual information to develop a comprehensive framework for proactive handover in heterogeneous environments

The development and deployment of several wireless and cellular networks mean that users will demand to be always connected as they move around. Mobile nodes will therefore have several interfaces and connections will be seamlessly switched among available networks using vertical handover techniques. Proactive handover mechanisms can be combined with the deployment of a number of location-based systems that provide location information to a very high degree of accuracy in different contexts. Furthermore, this new environment will also allow contextual information such as user profiles as well as the availability of local services to be combined to provide optimal communications for mobile users. The goal of this paper is therefore to explore the development of a comprehensive framework for achieving optimal communication in heterogeneous wireless environments using location and contextual information to provide efficient handover mechanisms. Using location-based techniques, it is possible to demonstrate that the Time Before Vertical Handover as well as the Network Dwell Time can be accurately estimated. These techniques are dependent on accurately estimating the handover radius. This paper investigates how location and context awareness can be used to estimate the best handover radius. The paper also explores how such techniques may be integrated into the Y-Comm architecture which is being used to explore the development of future mobile networks. Finally, the paper highlights the use of ontological techniques as a mechanism for specifying and prototyping such systems

Functional properties of glass–ceramic composites containing industrial inorganic waste and evaluation of their biological compatibility

Abstract A study has been carried out on the feasibility of using Latvian industrial waste (peat cool ash, fly ash, aluminium scrap metal processing waste, metallurgical slag and waste cullet glass) and raw mineral materials (limeless clay) to produce dense, frost resistant, chemically durable glass–ceramic materials by powder technology. Highly crystalline and dense products (density: 2.50–2.94 g/cm3, water uptake: 1.3–4.3%) were fabricated from different mixtures by sintering at temperatures in the range of 1060–1160 °C. Glass–ceramics were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and four point bending strength test. Chemical durability, soluble salt crystallization as well as biological tests were carried out in order to evaluate the environmental stability and possible toxicity of the materials. The novel glass–ceramics developed here can find applications as building materials, such as wall tiles and for manufacturing industrial floors