Detection of chromosome aberrations in the human interphase nucleus by visualization of specific target DNAs with radioactive and non-radioactive in situ hybridization techniques: diagnosis of trisomy 18 with probe L1.84

The localization of chromosome 18 in human interphase nuclei is demonstrated by use of radioactive and nonradioactive in situ hybridization techniques with a DNA clone designated L1.84. This clone represents a distinct subpopulation of the repetitive human alphoid DNA family, located in the centric region of chromosome 18. Under stringent hybridization conditions hybridization of L1.84 is restricted to chromosome 18 and reflects the number of these chromosomes present in the nuclei, namely, two in normal diploid human cells and three in nuclei from cells with trisomy 18. Under conditions of low stringency, cross-hybridization with other subpopulations of the alphoid DNA family occurs in the centromeric regions of the whole chromosome complement, and numerous hybridization sites are detected over interphase nuclei. Detection of chromosome-specific target DNAs by non-radioactive in situ hybridization with appropriate DNA probes cloned from individual chromosomal subregions presents a rapid means of identifying directly numerical or even structural chromosome aberrations in the interphase nucleus. Present limitations and future applications of interphase cytogenetics are discussed

Ultradian Cortisol Pulsatility Encodes a Distinct, Biologically Important Signal

Cortisol is released in ultradian pulses. The biological relevance of the resulting fluctuating cortisol concentration has not been explored.Determination of the biological consequences of ultradian cortisol pulsatility.A novel flow through cell culture system was developed to deliver ultradian pulsed or continuous cortisol to cells. The effects of cortisol dynamics on cell proliferation and survival, and on gene expression were determined. In addition, effects on glucocorticoid receptor (GR) expression levels and phosphorylation, as a potential mediator, were measured.Pulsatile cortisol caused a significant reduction in cell survival compared to continuous exposure of the same cumulative dose, due to increased apoptosis. Comprehensive analysis of the transcriptome response by microarray identified genes with a differential response to pulsatile versus continuous glucocorticoid delivery. These were confirmed with qRT-PCR. Several transcription factor binding sites were enriched in these differentially regulated target genes, including CCAAT-displacement protein (CDP). A CDP regulated reporter gene (MMTV-luc) was, as predicted, also differentially regulated by pulsatile compared to continuous cortisol delivery. Importantly there was no effect of cortisol delivery kinetics on either GR expression, or activation (GR phosphoSer(211)).Cortisol oscillations exert important effects on target cell gene expression, and phenotype. This is not due to differences in cumulative cortisol exposure, or either expression, or activation of the GR. This suggests a novel means to regulate GR function

Label-free cell separation and sorting in microfluidic systems

Cell separation and sorting are essential steps in cell biology research and in many diagnostic and therapeutic methods. Recently, there has been interest in methods which avoid the use of biochemical labels; numerous intrinsic biomarkers have been explored to identify cells including size, electrical polarizability, and hydrodynamic properties. This review highlights microfluidic techniques used for label-free discrimination and fractionation of cell populations. Microfluidic systems have been adopted to precisely handle single cells and interface with other tools for biochemical analysis. We analyzed many of these techniques, detailing their mode of separation, while concentrating on recent developments and evaluating their prospects for application. Furthermore, this was done from a perspective where inertial effects are considered important and general performance metrics were proposed which would ease comparison of reported technologies. Lastly, we assess the current state of these technologies and suggest directions which may make them more accessible

Dynamic Control of Robot Perception Using Stochastic Spatial Models

Robot perception has traditionally been addressed as a passive and incidental activity, rather than an active and task-directed activity. Consequently, although sensor systems are essential to provide the information required by the decision-making and actuation components of a robot system, no explicit planning and control of the sensory activities of the robot is performed. This has lead to the development of sensor modules that are either excessively specialized, or inefficient and unfocused in their informational output. In this paper, we develop strategies for the dynamic control of robot perception, using stochastic sensor and spatial models to explicitly plan and control the sensory activities of an autonomous mobile robot, and to dynamically servo the robot and its sensors to acquire the information necessary for successful execution of robot tasks. We discuss the explicit characterization of robot task-specific information requirements, the use of information-theoretic measures to model the extent, accuracy and complexity of the robot’s world model, and the representation of inferences about the robot’s environment using the Inference Grid, a multiproperty tesselated random field model. We describe the use of stochastic sensor models to determine the utility of sensory actions, and to compute the loci of observation of relevant information. These models allow the development of various perception control strategies, including attention control and focussing, perceptual responsiveness to varying spatial complexity, and control of multi-goal perceptual activities. We illustrate these methodologies using an autonomous multi-sensor mobile robot, and show the application of dynamic perception strategies to active exploration and multi-objective motion planning.

Epitope Mapping by Epitope Excision, Hydrogen/Deuterium Exchange, and Peptide-Panning Techniques Combined with In Silico Analysis

The fine characterization of protective B cell epitopes plays a pivotal role in the development of novel vaccines. The development of epitope-based vaccines, in fact, cannot be possible without a clear definition of the antigenic regions involved in the binding between the protective antibody (Ab) and its molecular target. To achieve this result, different epitope-mapping approaches have been widely described (Clementi et al. Drug Discov Today 18(9-10):464-471, 2013). Nowadays, the best way to characterize an Ab bound region is still the resolution of Ab-antigen (Ag) co-crystal structure. Unfortunately, the crystallization approaches are not always feasible. However, different experimental strategies aimed to predict Ab-Ag interaction and followed by in silico analysis of the results may be good surrogate approaches to achieve this result. Here, we review few experimental techniques followed by the use of "basic" informatics tools for the analysis of the results

Anatomical characteristics and hydrologic signals in tree-rings of oaks (Quercus robur L.)

Q. robur decline in European floodplain forests in recent years seems to be strongly associated with the deteriorating hydrological regime. We investigated the influence of the Krka River flow on tree-ring patterns of Q. robur from the Krakovo floodplain forests (Slovenia) to assess the effect of micro-location conditions on hydrological signals in wood-anatomical characteristics. We selected two groups of Q. robur trees growing at nearby locations with different hydrological conditions, resulting in frequent autumn and spring flooding at the wetter site (=W oaks) but no flooding at the other, drier site (=D oaks). We found differences between the two groups in the anatomical structure of tree-rings; however, ring width proved to be the main variable determining the anatomical structure of oak wood. D and W oaks responded differently to the Krka River flow in the studied period. Radial growth of D oaks was negatively influenced by spring flow, but positively influenced by minimum summer flow. In W oaks, ring width was positively correlated with mean summer flow. Thus, environmental information stored in wood-anatomical features may vary, even within the same forest stand, and largely depends on the micro-environment. Reduced wood increments of D oaks suggest that growth conditions are less favourable, implying a link between the health state of oaks from lowland forest and hydrological conditions. Trees intended for hydrological reconstruction must therefore be carefully selected to avoid the possibility of error and potential loss of information. Anatomical characteristics and hydrological signals in tree-rings of oaks from areas with regular flooding may vary, even within the same forest stand, and largely depends on the micro-environmental conditions

Conceptualising Graduate Work Readiness: Theories, Concepts and Implications for Practice and Research

This chapter discusses the conceptualization of graduate work-readiness (GWR) and outlines the theoretical underpinnings associated with developing these conceptualisations. The chapter develops the Work-Related Integrated Competence Model (WRICM) as a comprehensive representation of the competency sets required by graduates to meet the expectations of the multiple stakeholders associated with the graduate transition process. The chapter evaluates the measurement of GWR using the WRICM models and compares it to other models used to measure GWR. The implications and possibilities of the WRICM model are then outlined. The proposed model provides a comprehensive foundation for evaluating GWR and for informing practice and policy around developing GWR attributes