8,232 research outputs found

    Annotated Bibliography: Anticipation

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    Evaluation of behavior in transgenic mouse models to understand human congenital pain conditions

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    BACKGROUND: Containing a brain for signal processing and decision making, and a peripheral component for sensation and response, the nervous system provides higher organisms a powerful method of interacting with their environment. The specific neurons involved in pain sensation are known as nociceptors and are the source of normal nociceptive pain signaling to prompt appropriate responses. Though acute hypersensitization can be advantageous by encouraging an organism to allow an injured area to heal, chronic pain conditions can be pathological and can markedly reduce quality of life. While a variety of genes have been associated with congenital pain conditions, two rare cases examined in this study have not had their mutated genes identified. Potassium voltage-gated channel subfamily H member 8, or KCNH8, is involved in regulating action potential production and propagation, and has not been linked with pain processing of any kind to date. Here, a male patient evaluated at Boston Children’s Hospital contains a novel single-base KCNH8 mutation and possesses an extremely low sensitivity to cold temperatures and mechanical pain, but a higher sensitivity to warmer temperatures. A separate protein, intersectin-2, or ITSN2, normally functions in clathrin-mediated endocytosis and exocytosis. A second patient at Boston Children’s Hospital expresses a previously-unseen point mutation in ITSN2 and experiences erythromelalgia, characterized by episodes of intense pain and red, swollen limbs during ambient warm temperatures. Through the use of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 genome editing, this study will produce these specific genetic mutations in mouse lines to explore their effects on mammalian behavior. OBJECTIVES: This project employs two transgenic mouse models to study the behavioral phenotypes associated with rare potentially damaging mutations in KCNH8 and ITSN2 exhibited in the human patients. Through these experiments, a greater understanding of neural pain signaling and sensitivity changes can occur. METHODS: The differences in temperature preference of KCNH8 and ITSN2 mutant mice compared to wild type mice lacking these mutations was studied using thermal plates under cold and warm conditions. Direct application of acetone and von Frey filaments to mouse paws was used to study cold and mechanical sensitivity. Further testing of stamina, anxiety, coordination, and strength were also evaluated. RESULTS: A marked decrease in sensitivity to von Frey stimulation (p<0.01) and acetone administration (p<0.05) was observed in KCNH8 mutant mice. Thermal preference testing demonstrated a decreased preference for warmer temperatures as compared to wild type mice. In addition, anxiety levels were also observed to be slightly higher in these mutant KCNH8 mice (p<0.05). The mutant ITSN2 mice spent less time at cooler temperatures, though surprisingly they significantly preferred warmer conditions as compared to their wild type littermates. A full and partial reversal of these temperature preferences was demonstrated in cold and heat thermal conditions respectively after intraperitoneal gabapentin injection, which normalized the mice toward wild type behavior. CONCLUSIONS: Data from the KCNH8 mutant mouse model indicates an aversion to warmer temperatures and a decreased ability to detect cold or mechanical pressure, much like the human patient. The mutant ITSN2 mice were less likely to spend time at cooler temperatures, indicating heightened sensory sensitivity, but their preference for warmer temperatures suggests a possible desensitization of the affected nociceptors. These results often mirror the patient’s phenotype, but the preference for ambient warmer environments appears opposite to the patient. As the ITSN2 mice feel discomfort at cooler temperatures, a proposed desensitization at warmer temperatures would result in a more comfortable environment and could explain the observed preference. The trends toward normal neural firing rates achieved through gabapentin injection suggest that the aberrant responses in mutant ITSN2 mice is due to altered sensitization, but additional examination under these conditions with a larger group of mice is necessary to further unravel these signaling pathways. However, these extremely encouraging data introduce two new molecular targets for acute pain control

    Children’s Fitness and Quality of Movement

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    Introduction: Movement is essential to life and plays a key role in development throughout childhood. Movement can be assessed by its quantity and quality. Movement is important to measure as it can aid early intervention. Current research suggests that global levels of fitness are declining, with a lack of research surrounding children’s natural fitness levels as they get older. Quantity of movement is commonly studied, however quality is becoming increasingly popular. A clear understanding of the methods of technology used to measure quality of movement is important as understanding this area will aid in designing appropriate interventions.Methods: This thesis comprises of two experimental studies. Study one is a repeated measures design using previously collected Swanlinx data to investigate how components of children’s fitness change over a one-year period. Study two is a scoping review investigating the measurement of quality of movement with technology in the form of MEM’s devices, while aiming to gain clarity on the definition of quality.Results: Study one revealed that children’s fitness levels increase across a one-year period, in all components of fitness, except sit and reach. Boys performed significantly better in all fitness components, apart from sit and reach. Study two demonstrated the broad field that is included under the term of quality, showing clarity is needed in this area. A large number of devices, movements and populations are being observed, with multiple definitions of quality which is dependent on the metrics collected.Conclusion: Study one concludes that children’s fitness levels increase over one-year, with boys performing better than girls. This can be used to understand children’s natural fitness levels and aid future interventions in participation. Study two concludes that there are multiple ways to assess quality of movement however a clear definition of the quality should be stated, aiding comparison of quality

    Seasonal undernutrition in rural Ethiopia:

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    Marked seasonal variability of both production- and consumption is characteristic of virtually all farming systems in the developing world. This study examines the magnitude and significance of seasonal undernutrition in south central Ethiopia, southern Shewa and Zigwa Boto, a peasant association in the Gurage Zone. The study seeks to answer five questions: (1)Does seasonal energy stress affect individuals of various age groups and sexes differently? (2)Do members of the same household show divergent responses to seasonal energy stress? (3)What are the functional consequences of different levels of adult undernutrition? (4)Are the current anthropometric cut-off points for adults appropriate for rural Ethiopia? (5)What household characteristics are associated with vulnerability to seasonal undernutrition? A number of important findings emerge from this research.....The study clarifies some points of contention in the field of adult undernutrition and shows how seasonal undernutrition operates as an intermittent warning signal, reminding us not to miss opportunities to promote good nutrition throughout the life cycle.Nutrition, Ethiopia, Malnutrition., Food crops., Climate.,

    European Paediatric Formulation Initiative (EuPFI)-Formulating Ideas for Better Medicines for Children.

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    © American Association of Pharmaceutical Scientists 2016, published by Springer US, available online at doi: https://doi.org/10.1208/s12249-016-0584-1The European Paediatric Formulation Initiative (EuPFI), founded in 2007, aims to promote and facilitate the preparation of better and safe medicines for children through linking research and information dissemination. It brings together the capabilities of the industry, academics, hospitals, and regulators within a common platform in order to scope the solid understanding of the major issues, which will underpin the progress towards the future of paediatric medicines we want.The EuPFI was formed in parallel to the adoption of regulations within the EU and USA and has served as a community that drives research and dissemination through publications and the organisation of annual conferences. The membership and reach of this group have grown since its inception in 2007 and continue to develop and evolve to meet the continuing needs and ambitions of research into and development of age appropriate medicines. Five diverse workstreams (age-appropriate medicines, Biopharmaceutics, Administration Devices, Excipients and Taste Assessment & Taste Masking (TATM)) direct specific workpackages on behalf of the EuPFI. Furthermore, EuPFI interacts with multiple diverse professional groups across the globe to ensure efficient working in the area of paediatric medicines. Strong commitment and active involvement of all EuPFI stakeholders have proved to be vital to effectively address knowledge gaps related to paediatric medicines, discuss potential areas for further research and identify issues that need more attention and analysis in the future.Peer reviewedFinal Accepted Versio

    Initial action output and feedback-guided motor behaviors in autism spectrum disorder

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    Background Sensorimotor issues are common in autism spectrum disorder (ASD), related to core symptoms, and predictive of worse functional outcomes. Deficits in rapid behaviors supported primarily by feedforward mechanisms, and continuous, feedback-guided motor behaviors each have been reported, but the degrees to which they are distinct or co-segregate within individuals and across development are not well understood. Methods We characterized behaviors that varied in their involvement of feedforward control relative to feedback control across skeletomotor (precision grip force) and oculomotor (saccades) control systems in 109 individuals with ASD and 101 age-matched typically developing controls (range: 5–29 years) including 58 individuals with ASD and 57 controls who completed both grip and saccade tests. Grip force was examined across multiple force (15, 45, and 85% MVC) and visual gain levels (low, medium, high). Maximum grip force also was examined. During grip force tests, reaction time, initial force output accuracy, variability, and entropy were examined. For the saccade test, latency, accuracy, and trial-wise variability of latency and accuracy were examined. Results Relative to controls, individuals with ASD showed similar accuracy of initial grip force but reduced accuracy of saccadic eye movements specific to older ages of our sample. Force variability was greater in ASD relative to controls, but saccade gain variability (across trials) was not different between groups. Force entropy was reduced in ASD, especially at older ages. We also find reduced grip strength in ASD that was more severe in dominant compared to non-dominant hands. Limitations Our age-related findings rely on cross-sectional data. Longitudinal studies of sensorimotor behaviors and their associations with ASD symptoms are needed. Conclusions We identify reduced accuracy of initial motor output in ASD that was specific to the oculomotor system implicating deficient feedforward control that may be mitigated during slower occurring behaviors executed in the periphery. Individuals with ASD showed increased continuous force variability but similar levels of trial-to-trial saccade accuracy variability suggesting that feedback-guided refinement of motor commands is deficient specifically when adjustments occur rapidly during continuous behavior. We also document reduced lateralization of grip strength in ASD implicating atypical hemispheric specialization
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