579 research outputs found
A role for DNA-dependent activator of interferon regulatory factor in the recognition of herpes simplex virus type 1 by glial cells
<p>Abstract</p> <p>Background</p> <p>The rapid onset of potentially lethal neuroinflammation is a defining feature of viral encephalitis. Microglia and astrocytes are likely to play a significant role in viral encephalitis pathophysiology as they are ideally positioned to respond to invading central nervous system (CNS) pathogens by producing key inflammatory mediators. Recently, DNA-dependent activator of IFN regulatory factor (DAI) has been reported to function as an intracellular sensor for DNA viruses. To date, the expression and functional role of DAI in the inflammatory responses of resident CNS cells to neurotropic DNA viruses has not been reported.</p> <p>Methods</p> <p>Expression of DAI and its downstream effector molecules was determined in C57BL/6-derived microglia and astrocytes, either at rest or following exposure to herpes simplex virus type 1 (HSV-1) and/or murine gammaherpesvirus-68 (MHV-68), by immunoblot analysis. In addition, such expression was studied in ex vivo microglia/macrophages and astrocytes from uninfected animals or mice infected with HSV-1. Inflammatory cytokine production by glial cultures following transfection with a DAI specific ligand (B-DNA), or following HSV-1 challenge in the absence or presence of siRNA directed against DAI, was assessed by specific capture ELISA. The production of soluble neurotoxic mediators by HSV-1 infected glia following DAI knockdown was assessed by analysis of the susceptibility of neuron-like cells to conditioned glial media.</p> <p>Results</p> <p>We show that isolated microglia and astrocytes constitutively express DAI and its effector molecules, and show that such expression is upregulated following DNA virus challenge. We demonstrate that these resident CNS cells express DAI <it>in situ</it>, and show that its expression is similarly elevated in a murine model of HSV-1 encephalitis. Importantly, we show B-DNA transfection can elicit inflammatory cytokine production by isolated glial cells and DAI knockdown can significantly reduce microglial and astrocyte responses to HSV-1. Finally, we demonstrate that HSV-1 challenged microglia and astrocytes release neurotoxic mediators and show that such production is significantly attenuated following DAI knockdown.</p> <p>Conclusions</p> <p>The functional expression of DAI by microglia and astrocytes may represent an important innate immune mechanism underlying the rapid and potentially lethal inflammation associated with neurotropic DNA virus infection.</p
Longitudinal patterns in an Arkansas River Valley stream: an Application of the River Continuum Concept
The River Continuum Concept (RCC) provides the framework for studying how lotic ecosystems vary from headwater streams to large rivers. The RCC was developed in streams in eastern deciduous forests of North America, but watershed characteristics and land uses differ across ecoregions, presenting unique opportunities to study how predictions of the RCC may differ across regions. Additionally, RCC predictions may vary due to the influence of fishes, but few studies have used fish taxa as a metric for evaluating predictions of the RCC. Our goal was to determine if RCC predictions for stream orders 1 through 5 were supported by primary producer, macroinvertebrate, and fish communities in Cadron Creek of the Arkansas River Valley. We sampled chlorophyll a, macroinvertebrates, and fishes at five stream reaches across a gradient of watershed size. Contrary to RCC predictions, chlorophyll a did not increase in concentration with catchment size. As the RCC predicts, fish and macroinvertebrate diversity increased with catchment size. Shredding and collecting macroinvertebrate taxa supported RCC predictions, respectively decreasing and increasing in composition as catchment area increased. Herbivorous and predaceous fish did not follow RCC predictions; however, surface-water column feeding fish were abundant at all sites as predicted. We hypothesize some predictions of the RCC were not supported in headwater reaches of this system due to regional differences in watershed characteristics and altered resource availability due to land use surrounding sampling sites
Coinductive subtyping for abstract compilation of object-oriented languages into Horn formulas
In recent work we have shown how it is possible to define very precise type
systems for object-oriented languages by abstractly compiling a program into a
Horn formula f. Then type inference amounts to resolving a certain goal w.r.t.
the coinductive (that is, the greatest) Herbrand model of f.
Type systems defined in this way are idealized, since in the most interesting
instantiations both the terms of the coinductive Herbrand universe and goal
derivations cannot be finitely represented. However, sound and quite expressive
approximations can be implemented by considering only regular terms and
derivations. In doing so, it is essential to introduce a proper subtyping
relation formalizing the notion of approximation between types.
In this paper we study a subtyping relation on coinductive terms built on
union and object type constructors. We define an interpretation of types as set
of values induced by a quite intuitive relation of membership of values to
types, and prove that the definition of subtyping is sound w.r.t. subset
inclusion between type interpretations. The proof of soundness has allowed us
to simplify the notion of contractive derivation and to discover that the
previously given definition of subtyping did not cover all possible
representations of the empty type
Measuring Cognitive Reflection without Maths: Development and Validation fo the Verbal Cognitive Reflection Test
The Cognitive Reflection Test (CRT) became popular for its impressive power to predict how well people reason and make decisions. Despite the popularity of the CRT, a major issue complicates its interpretation: the numerical nature of the CRT confounds reflection ability with mathematical ability. We have addressed this issue by developing the Verbal CRT (CRT-V), a novel 10-item measure of cognitive reflection (https://osf.io/xehbv/), using non-mathematical problems with good statistical and psychometric properties and with low familiarity. First, we selected suitable items with relatively low familiarity and optimal difficulty as identified in two different populations (Studies 1 and 2) and with high content validity as judged by an expert panel (Study 3). Second, we demonstrated good criterion and construct validity for the test in different populations with a wide range of variables (Studies 4-6, 8) and a good internal consistency and test-retest reliability (Study 7). The Verbal CRT was less associated with math anxiety, objective and subjective numeracy than the original CRT and it was test equivalent across gender, age groups and administration setting. In contrast with the original CRT (Hedge’s g = 0.29, 95% CI[0.17, 0.40]), the Verbal CRT showed no gender differences (Hedge’s g = -0.06, 95% CI[-0.18, 0.06]). The Verbal CRT can complement existing, numerical, tests of cognitive reflection
Ant colonies: building complex organizations with minuscule brains and no leaders
Thus far the articles in the series JOD calls the “Organization Zoo” have employed the notion of a “zoo” metaphorically to describe an array of human institutions. Here we take the term literally to consider the design of the most complex organizations in the living world beside those of humans, a favorite of insect zoos around the world: ant colonies. We consider individuality and group identity in the functioning of ant organizations; advantages of a flat organization without hierarchies or leaders; self-organization; direct and indirect communication; job specialization; labor coordination; and the role of errors in innovation. The likely value and limitations of comparing ant and human organizations are briefly examined
Investigating corroboration of self-perceived posttraumatic growth among Sri Lankan Tamil survivors of ethnopolitical warfare through trait, domain, and profile agreement approaches.
Though research on assessing posttraumatic growth has been severely critiqued, some evidence suggests close others can observe and report changes in individuals following traumatic life events and are sensitive to idiosyncratic ways in which changes manifest. We extended these findings by investigating corroboration of self-perceived posttraumatic growth (PTG) and depreciation (PTD) as measured by the Posttraumatic Growth Inventory–42 (PTGI-42) among Sri Lankan Tamil war survivors (n = 200). Informants slightly corroborated overall levels of PTG and PTD, while a more nuanced profile analysis procedure revealed overall—but not distinctive—profile agreement. This suggests self–other agreement is modest and may partly reflect shared narratives and collective cultural understandings about how people change after trauma. Results demonstrate further that informants were not sensitive to idiosyncratic ways in which target individuals had changed. Together, the lack of validity evidence suggests that the PTGI-42 may be inadequate in some cross-cultural contexts as a measure of nuanced posttraumatic change (i.e., as a measure of specific changes in the five theorized domains of growth and depreciation). Future work should emphasize culture- and context-sensitive measurement of posttraumatic change, particularly focusing on methods other than retrospective self-reports, such as prospective longitudinal designs
Effects of atomoxetine on growth in children with attention-deficit/hyperactivity disorder following up to five years of treatment.
OBJECTIVE: To examine the effects on growth of long-term pharmacological treatment for attention-deficit/hyperactivity disorder (ADHD), we present findings from an ongoing 5-year study of the efficacy and safety of treatment with atomoxetine.
METHODS: North American patients, 6-17 years old at study entry (N = 1,312) and with Diagnostic and Statistical Manual of Mental Disorders,4th edition (DSM-IV) ADHD, were studied under open-label atomoxetine treatment. Sixty-one were studied up to 5 years.
RESULTS: After 1 month\u27s treatment, patients weighed less than expected from their starting percentiles relative to population norms, with a maximum shortfall at 15 months and a return to expected weight by 36 months. Patients were slightly shorter than expected after 12 months, reaching a maximum shortfall at 18 months and returning to expected height by 24 months. Patients in the top quartile for body mass index (BMI) or weight at baseline, and those in the third quartile for height, showed 5-year decreases from expected values. Those below median height at baseline showed increases relative to expected values.
CONCLUSIONS: These interim results indicate that continuous atomoxetine treatment for up to 5 years has little or no long-term effect on juvenile growth and final stature for most patients, although persistent decreases from expected may occur in some patients who are larger than average before treatment
Re-evaluating the Self-Report Habit Index: the cases of Physical Activity and Snacking habits
Objective. The Self-Report Habit Index (SRHI) was originally reported as one-dimensional (Verplanken and Orbell, 2003). Nevertheless, habit has been described as characterized by several features, and one-dimensional models for the SRHI have shown poor fit. Therefore, we aimed to compare multi-dimensional models with a one-dimension model in both snacking and physical activity habits, besides examining further instrument characteristics.
Design. A cross-sectional study was conducted with high school and university students (n = 555).
Main outcome measure. The SRHI adapted for physical activity and for snaking habits was applied at one single time.
Results. Nested models with one factor, two factors, and three factors were compared. Then, a hierarchical second-order model was tested, and further validity issues, as well as invariance between habits, were examined.
Three-dimensional models represented a better fit for both habits. However, fit was still non-adequate in the snacking version. Also, discriminant validity concerns raised for the physical activity SRHI. Also, invariance between the snacking and the physical activity versions was not confirmed.
Conclusions. Considering the SRHI as composed by the dimensions of “lack of awareness”, “lack of control”, and “history of behavioural repetition” seems to be more accurate. Nevertheless, our findings suggest that further research is needed.Universidad de Costa Rica/[723-B7-306]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Sociales::Instituto de Investigaciones Psicológicas (IIP
Gender-based food intake stereotype scale (GBFISS) for adolescents: development and psychometric evaluation
Objective. The study aimed to develop and test the validity and reliability of a gender-based food intake stereotype scale (GBFISS) to further the understanding of gender stereotype influences on food intake. Design. Two cross-sectional studies were conducted among adolescents. In the first one (n = 611), exploratory and confirmatory factor analyses were performed on subsamples to identify and cross-validate the scale’s structure. Evidence of concurrent validity (correlation with sexism) was also examined. In the second study (n = 813), confirmatory factor analysis was conducted to confirm the scale’s dimensionality on a different sample. Further evidence of construct validity (correlations with food intake and social desirability) was examined. Invariance was tested for different features as well. Main outcome. The Gender-Based Food Intake Stereotype Scale. Results. Factor analyses on the first and second studies helped identify and confirm the GBFISS as a three-dimensional scale. The studies also provided evidence of construct validity. Support for invariance by gender and age was found, and reliability was acceptable. Conclusion. The evidence suggests that the GBFISS is valid and reliable. Further research is recommended. The contribution of gender stereotypes, as measured by the GBFISS, to well-established health behavior models should be examined.Ministerio de Salud/[DM-FG-4854-14 and DM-FG.1748-2018]//Costa RicaFundación INCIENSA/[]/FUNIN/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Sociales::Instituto de Investigaciones Psicológicas (IIP
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