Applications of mass spectrometry to the study of siRNA

RNA interference (RNAi) has quickly become a well‐established laboratory tool for regulating gene expression and is currently being explored for its therapeutic potential. The design and use of double‐stranded RNA oligonucleotides as therapeutics to trigger the RNAi mechanism and a greater effort to understand the RNAi pathway itself is driving the development of analytical techniques that can characterize these oligonucleotides. Electrospray (ESI) and MALDI have been used routinely to analyze oligonucleotides and their ability to provide mass and sequence information has made them ideal for this application. Reviewed here is the work done to date on the use of ESI and MALDI for the study of RNAi oligonucleotides as well as the strategies and issues associated with siRNA analysis by mass spectrometry. While there is not a large body of literature on the specific application of mass spectrometry to RNAi, the work done in this area is a good demonstration of the range of experiments that can be conducted and the value that ESI and MALDI can provide to the RNAi field. © 2010 Wiley Periodicals, Inc., Mass Spec Rev 30:979–998, 2011     

Sex and ethnic differences in the use of power.

Hypothesized that women and Chicanos would make less internal and more external attributions for their own successful performance than would Anglo males. 40 Chicano male, 40 Chicano female, 40 Anglo male, and 40 Anglo female undergraduates participated as managers in an industrial simulation study. Ss were randomly assigned to 1 of 4 experimental conditions: designated powers vs unspecified powers, and supervision of male or female workers. Following the managerial task, Ss completed a questionnaire assessing their own performance and that of their workers. All Anglos devalued their workers as a function of controlling power and attributed workers' performance to external factors. All Ss tended to use their power to persuade workers. Males attempted to influence workers to a greater degree than did females. The predicted sex differences in terms of attribution were evident only among Anglos. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prediction of psychological symptoms under high-risk psychosocial circumstances: Life events, social support, and symptom specificity.

Examined life events, perceived dimensions of events, and social support in predicting different types of psychological symptoms (e.g., depressive and anxiety symptoms), all within the context of a specific high-risk situation for psychological distress: the final-examination period for university students (N?=?167). Ss were administered a battery of tests that included the State-Trait Anxiety Inventory and the Beck Depression Inventory. Results indicate that (a) certain dimensions of events and particular aspects of social support are directly related to symptoms manifested during final-examination stress, (b) perceived dimensions of events and social support interactively predict symptoms, and (c) depressive symptoms—in contrast to general distress or anxiety symptoms—are relatively specifically a function of events and support. Findings are discussed within the context of existing research; the implications for extending similar strategies employing other high-risk psychosocial circumstances are advanced. (59 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Is there more to complicated grief than depression and posttraumatic stress disorder? A test of incremental validity.

There is growing interest in complicated grief reactions as a possible new diagnostic category for inclusion in the Diagnostic and Statistical Manual of Mental Disorders. However, no research has yet shown that complicated grief has incremental validity (i.e., predicts unique variance in functioning). The authors addressed this issue in 2 studies by comparing grief, depression, and posttraumatic stress disorder (PTSD) symptoms with different measures of functioning (interviewer ratings, friend ratings, self-report, and autonomic arousal). The 1st study (N = 73) used longitudinal data collected at 4 and 18 months postloss, and the 2nd study (N = 447) used cross-sectional data collected 2.5-3.5 years postloss. With depression and PTSD controlled, grief emerged as a unique predictor of functioning, both cross-sectionally and prospectively. The findings provide convergent support for the incremental validity of complicated grief as an independent marker of bereavement-related psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

TOWARD LEARNING GRID INFRASTRUCTURES: AN OVERVIEW OF RESEARCH ON GRID LEARNING SERVICES

The Learning Grid refers to the promise of projects that pool together instructional materials on distant computers. The Grid provides a wide range of available and potential learning services and resources and does not simply refer to taking advantage of the multiplying effects of connectivity. It supports the personalized use of the collective intelligence provided by networked computers and supports the exchange, negotiation, and dialogue within and among virtual, evolutionary, and pervasive learning communities. This article provides an overview of papers from the first workshop on Grid Learning Services, which brought together researchers discussing their views of infrastructure, services, and resources. It also addresses several research questions, including: What are the relevant resources and services and how can they be identified or built? How do they rely on the basic open Grid service architecture? How can intelligent tutoring systems be built on the Grid? How do the performance, efficiency, usability, and the global ability of those services meet individual and collective users' expectations?     

Ultrafine Particle Deposition in a Human Tracheobronchial Cast

The deposition of 0.20, 0.15, and 0.04 μm diameter particles was measured in a human central airway cast using a variable larynx with cyclic inspiratory flow. Data were compared with theoretical predictions for deposition from laminar flow for the first seven airway generations. With the exception of tracheal deposition, which on average exceeded predictions by a factor of 9, the measured deposition was about twice that predicted. The enhanced deposition is attributable to secondary swirling flows. Less enhancement is observed at higher inspiratory flow rates as turbulence increases. The surface density of particles deposited at bifurcations was approximately 20% greater than along the airway lengths. This increased deposition at bifurcations should be considered when calculating tissue dose for particles which act before the initial deposit is removed by clearance processes.     

Validation of the Adult Suicidal Ideation Questionnaire and the Reasons for Living Inventory in an adult psychiatric inpatient sample.

This study investigated the factor structure of the Adult Suicidal Ideation Questionnaire (ASIQ) and the Linehan Reasons for Living Inventory (LRFI) in a sample of 205 adult psychiatric inpatients. Confirmatory factor analyses provided moderate support for the construct validity of each instrument. Coefficient alphas for the ASIQ (.98) and LRFL (.93) were high. In addition, a range of different clinical cutoff points was derived for each instrument. Both instruments were also better than chance in differentiating between the suicide attempter and psychiatric control groups. High ASIQ and low LRFL scores were significantly associated with scores on selected Minnesota Multiphasic Personality Inventory-2 Content scales. The analyses also indicated that only the ASIQ added to the symptoms of hopelessness and negative affect in differentiating between the suicide attempter and psychiatric control groups. Results suggest that both instruments may be useful screening tests for suicidal behavior in psychiatric long-term care inpatient samples. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ability of periaqueductal gray subdivisions and adjacent loci to elicit analgesia and ability of naloxone to reverse analgesia.

This study is an investigation of the effects of stimulation of regions within and adjacent to the periaqueductal gray (PAG) matter. Eighty-five rats were implanted with 1 monopolar stimulating electrode into 1 of 5 loci. Potency of analgesia was evaluated by relative increases in tailflick latencies after brain stimulation, and threshold current intensity was used to elicit analgesia. The ability of naloxone to reverse the stimulation-induced analgesia was also evaluated. Results replicate the previous finding of differential naloxone reversibility of ventral vs. dorsal PAG sites, but they do not support a regional distinction in the potency of analgesia induced. The results suggest that dorsal PAG sites are involved in a separate nonopiate pain-inhibitory system, whereas ventral sites are involved in an opiate system. These systems, however, do not respect the cytoarchitectural boundaries of the PAG because sites adjacent to the PAG elicit similar effects with a corresponding dorsal-ventral distinction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

User Survey of Subjective Preference for Street-Lighting Sources

A telephone survey was conducted to assess user subjective preferences for metal halide versus high-pressure sodium lighting used in the Neighborhood Streetlight Demonstration Project conducted by an electric utility company. A variety of univariate and multivariate parametric and nonparametric statistical tests were conducted. This analysis revealed that users rated metal halide higher on color and aesthetic dimensions, they rated metal halide and high-pressure sodium equal in terms of overall satisfaction, and they more frequently named metal halide as the preferred source for a street other than the one they live on. Residents living under metal halide lighting were seen to exhibit more of a loyalty for their source than did high-pressure sodium users. In agreement with previous studies, users' assessment of lighting quantity were uncorrelated with photometric measurements. We conclude that further studies are warranted because these suggested preferences and loyalties, if confirmed, would be important to consider in designing street lighting and in setting street-lighting policy.