898 research outputs found
Feedback and motor skill acquisition using a haptic dental simulator
Aim: To investigate the effect of qualitatively different types of pedagogical feedback (FB) on the training, transfer and retention of basic manual dexterity dental skills using a virtual reality (VR) haptic dental simulator. Methods: Sixty-three participants (M = 22.7 years; SD = 3.4 years), with no previous dental training, were randomly allocated to one of three groups (n = 21 each). Group 1 received device-only feedback during the training phase, that is the visual display of the simulator (DFB); Group 2 received verbal feedback from a qualified dental instructor (IFB); and Group 3 received a combination of instructor and device feedback (IDFB). Participants completed four tasks during which feedback was given according to group allocation as well as two skills transfer tests. Skill retention was examined immediately after training, at 1 week and at 1 month post-test. Results: Statistically significant differences were found between the groups in overall performance (P < 0.001) and error (P = 0.006). Post hoc comparisons revealed the IDFB group produced substantially better performance and fewer errors in comparison with DFB and IFB training. This difference translated to improved performance in skill retention and generalisation of knowledge to novel tasks. Conclusion: These data indicate that the acquisition and retention of basic dental motor skills in novice trainees is best optimised through a combination of instructor and visual display (VR)-driven feedback. The results have implications for the utility and implementation of VR haptic technology in dental education
Should prospective dental students be screened for colour vision deficits?
A perennial question in dental education is: what skills and aptitudes should be assessed in prospective dental students? Intellectual capacity and manual dexterity understandably rank highly, but are there minimum thresholds for visual perception that applicants need be able to demonstrate before they enter the profession? We have recently flagged this issue with regard to the thresholds of stereoscopic acuity required for a dentist when operating on teeth. In the present article, we highlight the issue of identifying a minimum acceptable level of colour vision
Lower cardiorespiratory fitness contributes to increased insulin resistance and fasting glycaemia in middle-aged South Asian compared with European men living in the UK
AIMS/HYPOTHESIS: This study aimed to determine the extent to which increased insulin resistance and fasting glycaemia in South Asian men, compared with white European men, living in the UK, was due to lower cardiorespiratory fitness (maximal oxygen uptake [[Formula: see text]]) and physical activity. METHODS: One hundred South Asian and 100 age- and BMI-matched European men without diagnosed diabetes, aged 40β70Β years, had fasted blood taken for measurement of glucose concentration, HOMA-estimated insulin resistance (HOMA(IR)), plus other risk factors, and underwent assessment of physical activity (using accelerometry), [Formula: see text], body size and composition, and demographic and other lifestyle factors. For 13 South Asian and one European man, HbA(1c) levels were >6.5% (>48Β mmol/mol), indicating potential undiagnosed diabetes; these men were excluded from the analyses. Linear regression models were used to determine the extent to which body size and composition, fitness and physical activity variables explained differences in HOMA(IR) and fasting glucose between South Asian and European men. RESULTS: HOMA(IR) and fasting glucose were 67% (pβ<β0.001) and 3% (pβ<β0.018) higher, respectively, in South Asians than Europeans. Lower [Formula: see text], lower physical activity and greater total adiposity in South Asians individually explained 68% (95% CI 45%, 91%), 29% (11%, 46%) and 52% (30%, 80%), respectively, and together explained 83% (50%, 119%) (all pβ<β0.001) of the ethnic difference in HOMA(IR). Lower [Formula: see text] and greater total adiposity, respectively, explained 61% (9%, 111%) and 39% (9%, 76%) (combined effect 63% [8%, 115%]; all pβ<β0.05) of the ethnic difference in fasting glucose. CONCLUSIONS/INTERPRETATION: Lower cardiorespiratory fitness is a key factor associated with the excess insulin resistance and fasting glycaemia in middle-aged South Asian, compared with European, men living in the UK. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00125-013-2969-y) contains peer-reviewed but unedited supplementary material, which is available to authorised users
Clinical Practice Patterns for Hydroxyurea Initiation in Young Children with Sickle Cell Disease
Query Filtering with Low-Dimensional Local Embeddings
The concept of local pivoting is to partition a metric space so that each element in the space is associated with precisely one of a fixed set of reference objects or pivots. The idea is that each object of the data set is associated with the reference object that is best suited to filter that particular object if it is not relevant to a query, maximising the probability of excluding it from a search. The notion does not in itself lead to a scalable search mechanism, but instead gives a good chance of exclusion based on a tiny memory footprint and a fast calculation. It is therefore most useful in contexts where main memory is at a premium, or in conjunction with another, scalable, mechanism. In this paper we apply similar reasoning to metric spaces which possess the four-point property, which notably include Euclidean, Cosine, Triangular, Jensen-Shannon, and Quadratic Form. In this case, each element of the space can be associated with two reference objects, and a four-point lower-bound property is used instead of the simple triangle inequality. The probability of exclusion is strictly greater than with simple local pivoting; the space required per object and the calculation are again tiny in relative terms. We show that the resulting mechanism can be very effective. A consequence of using the four-point property is that, for m reference points, there arèarè m 2 ´ pivot pairs to choose from, giving a very good chance of a good selection being available from a small number of distance calculations. Finding the best pair has a quadratic cost with the number of references ; however, we provide experimental evidence that good heuristics exist. Finally, we show how the resulting mechanism can be integrated with a more scalable technique to provide a very significant performance improvement, for a very small overhead in build-time and memory cost. Keywords: metric search · extreme pivoting · supermetric space · four-point property · pivot based index 2 ChÑvez et al
The transcriptional response of Caenorhabditis elegans to ivermectin exposure identifies novel genes involved in the response to reduced food intake
We have examined the transcriptional response of Caenorhabditis elegans following exposure to the anthelmintic drug ivermectin (IVM) using whole genome microarrays and real-time QPCR. Our original aim was to identify candidate molecules involved in IVM metabolism and/or excretion. For this reason the IVM tolerant strain, DA1316, was used to minimise transcriptomic changes related to the phenotype of drug exposure. However, unlike equivalent work with benzimidazole drugs, very few of the induced genes were members of xenobiotic metabolising enzyme families. Instead, the transcriptional response was dominated by genes associated with fat mobilization and fatty acid metabolism including catalase, esterase, and fatty acid CoA synthetase genes. This is consistent with the reduction in pharyngeal pumping, and consequential reduction in food intake, upon exposure of DA1316 worms to IVM. Genes with the highest fold change in response to IVM exposure, cyp-37B1, mtl-1 and scl-2, were comparably up-regulated in response to shortβterm food withdrawal (4 hr) independent of IVM exposure, and GFP reporter constructs confirm their expression in tissues associated with fat storage (intestine and hypodermis). These experiments have serendipitously identified novel genes involved in an early response of C. elegans to reduced food intake and may provide insight into similar processes in higher organisms
Improving Data Collection in Pregnancy Safety Studies: Towards Standardisation of Data Elements in Pregnancy Reports from Public and Private Partners, A Contribution from the ConcePTION Project
\ua9 2023, The Author(s).Introduction and Objective: The ConcePTION project aims to improve the way medication use during pregnancy is studied. This includes exploring the possibility of developing a distributed data processing and analysis infrastructure using a common data model that could form a foundational platform for future surveillance and research. A prerequisite would be that data from various data access providers (DAPs) can be harmonised according to an agreed set of standard rules concerning the structure and content of the data. To do so, a reference framework of core data elements (CDEs) recommended for primary data studies on drug safety during pregnancy was previously developed. The aim of this study was to assess the ability of several public and private DAPs using different primary data sources focusing on multiple sclerosis, as a pilot, to map their respective data variables and definitions with the CDE recommendations framework. Methods: Four pregnancy registries (Gilenya, Novartis; Aubagio, Sanofi; the Organization of Teratology Information Specialists [OTIS]; Aubagio, Sanofi; the Dutch Pregnancy Drug Register, Lareb), two enhanced pharmacovigilance programmes (Gilenya PRIM, Novartis; MAPLE-MS, Merck Healthcare KGaA) and four Teratology Information Services (UK TIS, Jerusalem TIS, Zerifin TIS, Swiss TIS) participated in the study. The ConcePTION primary data source CDE includes 51 items covering administrative functions, the description of pregnancy, maternal medical history, maternal illnesses arising in pregnancy, delivery details, and pregnancy and infant outcomes. For each variable in the CDE, the DAPs identified whether their variables were: identical to the one mentioned in the CDE; derived; similar but with a divergent definition; or not available. Results: The majority of the DAP data variables were either directly taken (85%, n = 305/357, range 73β94% between DAPs) or derived by combining different variables (12%, n = 42/357, range 0β24% between DAPs) to conform to the CDE variables and definitions. For very few of the DAP variables, alignment with the CDE items was not possible, either because of divergent definitions (1%, n = 3/357, range 0β2% between DAPs) or because the variables were not available (2%, n = 7/357, range 0β4% between DAPs). Conclusions: Data access providers participating in this study presented a very high proportion of variables matching the CDE items, indicating that alignment of definitions and harmonisation of data analysis by different stakeholders to accelerate and strengthen pregnancy pharmacovigilance safety data analyses could be feasible
Addressing Recruitment Challenges in the Engage-HU Trial in Young Children with Sickle Cell Disease
Background: Sickle cell disease (SCD) is a genetic disorder that causes significant medical and neurologic morbidity in children. Hydroxyurea (HU) is the primary medication used to prevent these complications. National Heart, Lung, and Blood Institute (NHLBI) guidelines recommend offering HU to children as young as 9 months of age with SCD (HbSS or HbSB0 thalassemia) using a shared decision-making approach. Although HU has proven efficacious it remains underutilized and caregivers report that they are not always actively involved in the decision to initiate this therapy. Reasons for limited HU uptake likely include lack of clinician knowledge and training and negative caregiver perceptions. Thus, we developed the Engage-HU trial as a novel approach to address HU utilization barriers. A critical consideration for this trial was that SCD primarily affects individuals of African and Hispanic/Latino descent. In these minority populations, intervention trials are sometimes terminated early because of recruitment difficulties related to mistrust of research, caregiver burden, and transportation issues. As such, the Engage-HU trial design included best-practice strategies for recruiting people of color in research. This study describes these strategies, the initial recruitment plan, preliminary recruitment outcomes and strategies, and our procedural adaptations. Study Design and Methods: Engage-HU is a randomized control trial (NCT03442114) to assess how clinicians can engage caregivers in a shared discussion that considers their values and preferences and includes evidence that supports HU. Engage-HU compares two dissemination methods for clinicians to facilitate shared decision-making with caregivers of young children with SCD: 1) the American Society of Hematology Pocket Guide, and 2) the HU Shared-Decision Making (H-SDM) Toolkit. The study aims to recruit 174 caregivers and evaluate the effectiveness of the dissemination methods on patient-centered outcomes (caregiver confidence in decision-making and perceptions of experiencing shared decision-making) as well as HU uptake and child health outcomes. Eligible children are aged 0 to 5 years, candidates for HU, and their caregiver has not made a decision about HU in the past 3 months. The trial is being conducted at 9 sites in the United States and uses a stepped-wedge design. Data will be analyzed based on the intent-to-treat principle. All participants will remain in the arm of the study to which they were randomized, regardless of whether or not they receive the assigned dissemination method. The primary endpoints are caregiver decisional uncertainty and caregiver perception of shared decision-making measured using validated tools. Data will be analyzed using a linear mixed effects regression model with a robust variance estimator and maximum likelihood estimation with observations clustered within site. The Engage-HU trial includes adaptations to increase recruitment such as tailored messaging, a relational recruitment approach, streamlined data collection, and a Stakeholder Advisory Committee. However, even with these adaptations, the first 6-months of the trial yielded lower than anticipated recruitment. Rather than terminate the trial or accept low enrollment, the research team implemented a series of recruitment strategies to address barriers including helping to improve research coordinator knowledge of the study purpose and adjusting no-show and follow-up procedures (e.g., calls to families after missed appointments and reminder calls before appointments). Site clinicians and clinic staff were provided with additional training so they could give more context about Engage-HU to caregivers and the study principal investigator led monthly "all coordinator" calls to provide support by sharing updates and experiences about successful recruitment. Implementation of these strategies resulted in triple the number of enrollments over the next 7-months compared to the previous 6-months (Table 1). Our goal in sharing this information is to provide lessons learned that can be implemented in future trials with the systematically underserved SCD population. It is also anticipated that methods described here may also inform clinical approaches to better engage caregivers of young children around critical clinical conversations, such as initiating medications like HU. Disclosures King: Magenta Therapeutics: Membership on an entity's Board of Directors or advisory committees; Bioline: Consultancy; RiverVest: Consultancy; Novimmune: Research Funding; Celgene: Consultancy; Tioma Therapuetics: Consultancy; Amphivena Therapeutics: Research Funding; WUGEN: Current equity holder in private company; Cell Works: Consultancy; Incyte: Consultancy. Smith-Whitley:Prime: Other: Education material; Celgene: Membership on an entity's Board of Directors or advisory committees; Global Blood Therapeutics: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Neumayr:Emmaus: Consultancy; Bayer: Consultancy; CTD Holdings: Consultancy; Pfizer: Consultancy; ApoPharma: Consultancy, Membership on an entity's Board of Directors or advisory committees; Micelle: Other: Site principal investigator; GBT: Other: Site principal investigator; PCORI: Other: site principal investigator; Novartis: Other: co-investigator; Bluebird Bio: Other: co-investigator; Sangamo Therapeutics: Other; Silarus: Other; Celgene: Other; La Jolla Pharmaceuticals: Other; Forma: Other; Imara: Other; National Heart, Lung, and Blood Institute: Other; Health Resources and Services Administration: Other; Centers for Disease Control and Prevention: Other; Seattle Children's Research: Other. Yates:Novartis: Research Funding. Thompson:Novartis: Consultancy, Honoraria, Research Funding; CRISPR/Vertex: Research Funding; BMS: Consultancy, Research Funding; Baxalta: Research Funding; Biomarin: Research Funding; bluebird bio, Inc.: Consultancy, Research Funding. </jats:sec
An Age-Structured Extension to the Vectorial Capacity Model
Vectorial capacity and the basic reproductive number (R(0)) have been instrumental in structuring thinking about vector-borne pathogen transmission and how best to prevent the diseases they cause. One of the more important simplifying assumptions of these models is age-independent vector mortality. A growing body of evidence indicates that insect vectors exhibit age-dependent mortality, which can have strong and varied affects on pathogen transmission dynamics and strategies for disease prevention.Based on survival analysis we derived new equations for vectorial capacity and R(0) that are valid for any pattern of age-dependent (or age-independent) vector mortality and explore the behavior of the models across various mortality patterns. The framework we present (1) lays the groundwork for an extension and refinement of the vectorial capacity paradigm by introducing an age-structured extension to the model, (2) encourages further research on the actuarial dynamics of vectors in particular and the relationship of vector mortality to pathogen transmission in general, and (3) provides a detailed quantitative basis for understanding the relative impact of reductions in vector longevity compared to other vector-borne disease prevention strategies.Accounting for age-dependent vector mortality in estimates of vectorial capacity and R(0) was most important when (1) vector densities are relatively low and the pattern of mortality can determine whether pathogen transmission will persist; i.e., determines whether R(0) is above or below 1, (2) vector population growth rate is relatively low and there are complex interactions between birth and death that differ fundamentally from birth-death relationships with age-independent mortality, and (3) the vector exhibits complex patterns of age-dependent mortality and R(0) βΌ 1. A limiting factor in the construction and evaluation of new age-dependent mortality models is the paucity of data characterizing vector mortality patterns, particularly for free ranging vectors in the field
Engaging Caregivers and Providers of Children With Sickle Cell Anemia in Shared Decision Making for Hydroxyurea: Protocol for a Multicenter Randomized Controlled Trial
BACKGROUND: Sickle cell anemia (SCA) is a genetic blood disorder that puts children at a risk of serious medical complications, early morbidity and mortality, and high health care utilization. Until recently, hydroxyurea was the only disease-modifying treatment for this life-threatening disease and has remained the only option for children younger than 5 years. Evidence-based guidelines recommend using a shared decision-making (SDM) approach for offering hydroxyurea to children with SCA (HbSS or HbS/Ξ²0 thalassemia) aged as early as 9 months. However, the uptake remains suboptimal, likely because caregivers lack information about hydroxyurea and have concerns about its safety and potential long-term side effects. Moreover, clinicians do not routinely receive training or tools, especially those that provide medical evidence and consider caregivers' preferences and values, to facilitate a shared discussion with caregivers. OBJECTIVE: The aim of this study is to understand how best to help parents of young children with sickle cell disease and their clinicians have a shared discussion about hydroxyurea (one that considers medical evidence and parent values and preferences). METHODS: We designed our study to compare the effectiveness of two methods for disseminating hydroxyurea guidelines to facilitate SDM: a clinician pocket guide (ie, usual care) and a clinician hydroxyurea SDM toolkit (H-SDM toolkit). Our primary outcomes are caregiver reports of decisional uncertainty and knowledge of hydroxyurea. The study also assesses the number of children (aged 0-5 years) who were offered and prescribed hydroxyurea and the resultant health outcomes. RESULTS: The Ethics Committee of the Cincinnati Children's Hospital Medical Center approved this study in November 2017. As of February 2021, we have enrolled 120 caregiver participants. CONCLUSIONS: The long-term objective of this study is to improve the quality of care for children with SCA. Using multicomponent dissemination methods developed in partnership with key stakeholders and designed to address barriers to high-quality care, caregivers of patients with SCA can make informed and shared decisions about their health. TRIAL REGISTRATION: ClinicalTrials.gov NCT03442114; https://clinicaltrials.gov/ct2/show/NCT03442114. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/27650
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