Epidemiology and reporting characteristics of preclinical systematic reviews

In an effort to better utilize published evidence obtained from animal experiments, systematic reviews of preclinical studies are increasingly more common-along with the methods and tools to appraise them (e.g., SYstematic Review Center for Laboratory animal Experimentation [SYRCLE's] risk of bias tool). We performed a cross-sectional study of a sample of recent preclinical systematic reviews (2015-2018) and examined a range of epidemiological characteristics and used a 46-item checklist to assess reporting details. We identified 442 reviews published across 43 countries in 23 different disease domains that used 26 animal species. Reporting of key details to ensure transparency and reproducibility was inconsistent across reviews and within article sections. Items were most completely reported in the title, introduction, and results sections of the reviews, while least reported in the methods and discussion sections. Less than half of reviews reported that a risk of bias assessment for internal and external validity was undertaken, and none reported methods for evaluating construct validity. Our results demonstrate that a considerable number of preclinical systematic reviews investigating diverse topics have been conducted; however, their quality of reporting is inconsistent. Our study provides the justification and evidence to inform the development of guidelines for conducting and reporting preclinical systematic reviews

Analysis of queries sent to PubMed at the point of care: Observation of search behaviour in a medical teaching hospital

Contains fulltext : 69801.pdf ( ) (Open Access)BACKGROUND: The use of PubMed to answer daily medical care questions is limited because it is challenging to retrieve a small set of relevant articles and time is restricted. Knowing what aspects of queries are likely to retrieve relevant articles can increase the effectiveness of PubMed searches. The objectives of our study were to identify queries that are likely to retrieve relevant articles by relating PubMed search techniques and tools to the number of articles retrieved and the selection of articles for further reading. METHODS: This was a prospective observational study of queries regarding patient-related problems sent to PubMed by residents and internists in internal medicine working in an Academic Medical Centre. We analyzed queries, search results, query tools (Mesh, Limits, wildcards, operators), selection of abstract and full-text for further reading, using a portal that mimics PubMed. RESULTS: PubMed was used to solve 1121 patient-related problems, resulting in 3205 distinct queries. Abstracts were viewed in 999 (31%) of these queries, and in 126 (39%) of 321 queries using query tools. The average term count per query was 2.5. Abstracts were selected in more than 40% of queries using four or five terms, increasing to 63% if the use of four or five terms yielded 2-161 articles. CONCLUSION: Queries sent to PubMed by physicians at our hospital during daily medical care contain fewer than three terms. Queries using four to five terms, retrieving less than 161 article titles, are most likely to result in abstract viewing. PubMed search tools are used infrequently by our population and are less effective than the use of four or five terms. Methods to facilitate the formulation of precise queries, using more relevant terms, should be the focus of education and research

Male-like sexual behavior of female mouse lacking fucose mutarotase

<p>Abstract</p> <p>Background</p> <p>Mutarotases are recently characterized family of enzymes that are involved in the anomeric conversions of monosaccharides. The mammalian fucose mutarotase (FucM) was reported in cultured cells to facilitate fucose utilization and incorporation into protein by glycosylation. However, the role of this enzyme in animal has not been elucidated.</p> <p>Results</p> <p>We generated a mutant mouse specifically lacking the fucose mutarotase (FucM) gene. The <it>FucM </it>knockout mice displayed an abnormal sexual receptivity with a drastic reduction in lordosis score, although the animals were fertile due to a rare and forced intromission by a typical male. We examined the anteroventral periventricular nucleus (AVPv) of the preoptic region in brain and found that the mutant females showed a reduction in tyrosine hydoxylase positive neurons compared to that of a normal female. Furthermore, the mutant females exhibited a masculine behavior, such as mounting to a normal female partner as well as showing a preference to female urine. We found a reduction of fucosylated serum alpha-fetoprotein (AFP) in a mutant embryo relative to that of a wild-type embryo.</p> <p>Conclusions</p> <p>The observation that <it>FucM</it>^-/-female mouse exhibits a phenotypic similarity to a wild-type male in terms of its sexual behavior appears to be due to the neurodevelopmental changes in preoptic area of mutant brain resembling a wild-type male. Since the previous studies indicate that AFP plays a role in titrating estradiol that are required to consolidate sexual preference of female mice, we speculate that the reduced level of AFP in <it>FucM</it>^-/-mouse, presumably resulting from the reduced fucosylation, is responsible for the male-like sexual behavior observed in the FucM knock-out mouse.</p

Maturation of monocyte-derived dendritic cells with Toll-like receptor 3 and 7/8 ligands combined with prostaglandin E2 results in high interleukin-12 production and cell migration

Dendritic cells (DC) are professional antigen-presenting cells of the immune system that play a key role in regulating T cell-based immunity. In vivo, the capacity of DC to activate T cells depends on their ability to migrate to the T cell areas of lymph nodes as well as on their maturation state. Depending on their cytokine-secreting profile, DC are able to skew the immune response in a specific direction. In particular, IL-12p70 producing DC drive T cells towards a T helper 1 type response. A serious disadvantage of current clinical grade ex vivo generated monocyte-derived DC is the poor IL-12p70 production. We have investigated the effects of Toll-like receptor (TLR)-mediated maturation on ex vivo generated human monocyte-derived DC. We demonstrate that in contrast to cytokine-matured DC, DC matured with poly(I:C) (TLR3 ligand) and/or R848 (TLR7/8 ligand) are able to produce vast amounts of IL-12p70, but exhibit a reduced migratory capacity. The addition of prostaglandin E2 (PGE2) improved the migratory capacity of TLR-ligand matured DC while maintaining their IL-12p70 production upon T cell encounter. We propose a novel clinical grade maturation protocol in which TLR ligands poly(I:C) and R848 are combined with PGE2 to generate DC with both high migratory capacity and IL-12p70 production upon T cell encounter

Does Cognitive Impairment Explain Behavioral and Social Problems of Children with Neurofibromatosis Type 1?

Thirty NF1-patients (mean age 11.7 years, SD = 3.3) and 30 healthy controls (mean age 12.5 years, SD = 3.1) were assessed on social skills, autistic traits, hyperactivity-inattention, emotional problems, conduct problems, and peer problems. Cognitive control, information processing speed, and social information processing were measured using 5 computer tasks. GLM analyses of variance showed significant group differences, to the disadvantage of NF1-patients, on all measures of behavior, social functioning and cognition. General cognitive ability (a composite score of processing speed, social information processing, and cognitive control) accounted for group differences in emotional problems, whereas social information processing accounted for group differences in conduct problems. Although reductions were observed for group differences in other aspects of behavior and social functioning after control for (specific) cognitive abilities, group differences remained evident. Training of cognitive abilities may help reducing certain social and behavioral problems of children with NF1, but further refinement regarding associations between specific aspects of cognition and specific social and behavioral outcomes is required

Machine learning algorithms for systematic review: reducing workload in a preclinical review of animal studies and reducing human screening error

BACKGROUND: Here, we outline a method of applying existing machine learning (ML) approaches to aid citation screening in an on-going broad and shallow systematic review of preclinical animal studies. The aim is to achieve a high-performing algorithm comparable to human screening that can reduce human resources required for carrying out this step of a systematic review. METHODS: We applied ML approaches to a broad systematic review of animal models of depression at the citation screening stage. We tested two independently developed ML approaches which used different classification models and feature sets. We recorded the performance of the ML approaches on an unseen validation set of papers using sensitivity, specificity and accuracy. We aimed to achieve 95% sensitivity and to maximise specificity. The classification model providing the most accurate predictions was applied to the remaining unseen records in the dataset and will be used in the next stage of the preclinical biomedical sciences systematic review. We used a cross-validation technique to assign ML inclusion likelihood scores to the human screened records, to identify potential errors made during the human screening process (error analysis). RESULTS: ML approaches reached 98.7% sensitivity based on learning from a training set of 5749 records, with an inclusion prevalence of 13.2%. The highest level of specificity reached was 86%. Performance was assessed on an independent validation dataset. Human errors in the training and validation sets were successfully identified using the assigned inclusion likelihood from the ML model to highlight discrepancies. Training the ML algorithm on the corrected dataset improved the specificity of the algorithm without compromising sensitivity. Error analysis correction leads to a 3% improvement in sensitivity and specificity, which increases precision and accuracy of the ML algorithm. CONCLUSIONS: This work has confirmed the performance and application of ML algorithms for screening in systematic reviews of preclinical animal studies. It has highlighted the novel use of ML algorithms to identify human error. This needs to be confirmed in other reviews with different inclusion prevalence levels, but represents a promising approach to integrating human decisions and automation in systematic review methodology

[11C]-DPA-713 and [18F]-DPA-714 as New PET Tracers for TSPO: A Comparison with [11C]-(R)-PK11195 in a Rat Model of Herpes Encephalitis

Background: Activation of microglia cells plays an important role in neurological diseases. Positron emission tomography (PET) with [C-11]-(R)-PK11195 has already been used to visualize activated microglia cells in neurological diseases. However, [C-11]-(R)-PK11195 may not possess the required sensitivity to visualize mild neuroinflammation. In this study, we evaluated the PET tracers [C-11]-DPA-713 and [F-18]-DPA-714 as agents for imaging of activated microglia in a rat model of herpes encephalitis. Materials and Methods: Rats were intranasally inoculated with HSV-1. On day 6 or 7 after inoculation, small animal PET studies were performed to compare [C-11]-(R)-PK11195, [C-11]-DPA-713, and [F-18]-DPA-714. Results: Uptake of [C-11]-DPA-713 in infected brain areas was comparable to that of [C-11]-(R)-PK11195, but [C-11]-DPA-713 showed lower non-specific binding. Non-specific uptake of [F-18]-DPA-714 was lower than that of [C-11]-(R)-PK11195. In the infected brain, total [F-18]-DPA-714 uptake was lower than that of [C-11]-(R)-PK11195, with comparable specific uptake. Conclusions: [C-11]-DPA-713 may be more suitable for visualizing mild inflammation than [C-11]-(R)-PK11195. In addition, the fact that [F-18]-DPA-714 is an agonist PET tracer opens new possibilities to evaluate different aspects of neuroinflammation. Therefore, both tracers warrant further investigation in animal models and in a clinical setting

Modified Vaccinia Virus Ankara Preferentially Targets Antigen Presenting Cells In Vitro, Ex Vivo and In Vivo

Modified Vaccinia virus Ankara (MVA) is a promising vaccine vector with an excellent safety profile. However, despite extensive pre-clinical and clinical testing, surprisingly little is known about the cellular tropism of MVA, especially in relevant animal species. Here, we performed in vitro, ex vivo and in vivo experiments with recombinant MVA expressing green fluorescent protein (rMVA-GFP). In both human peripheral blood mononuclear cells and mouse lung explants, rMVA-GFP predominantly infected antigen presenting cells. Subsequent in vivo experiments performed in mice, ferrets and non-human primates indicated that preferential targeting of dendritic cells and alveolar macrophages was observed after respiratory administration, although subtle differences were observed between the respective animal species. Following intramuscular injection, rMVA-GFP was detected in interdigitating cells between myocytes, but also in myocytes themselves. These data are important in advancing our understanding of the basis for the immunogenicity of MVA-based vaccines and aid rational vaccine design and delivery strategies

Efficacy of smoking prevention program 'Smoke-free Kids': study protocol of a randomized controlled trial

Contains fulltext : 77005.pdf (publisher's version ) (Open Access)Background - A strong increase in smoking is noted especially among adolescents. In the Netherlands, about 5% of all 10-year olds, 25% of all 13-year olds and 62% of all 17-year olds report ever smoking. In the U.S., an intervention program called 'Smoke-free Kids' was developed to prevent children from smoking. The present study aims to assess the effects of this home-based smoking prevention program in the Netherlands. Methods - A randomized controlled trial is conducted among 9 to 11-year old children of primary schools. Participants are randomly assigned to the intervention and control conditions. The intervention program consists of five printed activity modules designed to improve parenting skills specific to smoking prevention and parent-child communication regarding smoking. These modules will include additional sheets with communication tips. The modules for the control condition will include solely information on smoking and tobacco use. Initiation of cigarette smoking (first instance of puffing on a lighted cigarette), susceptibility to cigarette smoking, smoking-related cognitions, and anti-smoking socialization will be the outcome measures. To collect the data, telephone interviews with mothers as well as with their child will be conducted at baseline. Only the children will be examined at post-intervention follow-ups (6, 12, 24, and 36 months after the baseline). Discussion - This study protocol describes the design of a randomized controlled trial that will evaluate the effectiveness of a home-based smoking prevention program. We expect that a significantly lower number of children will start smoking in the intervention condition compared to control condition as a direct result of this intervention. If the program is effective, it is applicable in daily live, which will facilitate implementation of the prevention protocol. Trial registration: Netherlands Trial Register NTR146510 p

Ethical issues at the interface of clinical care and research practice in pediatric oncology: a narrative review of parents' and physicians' experiences

Contains fulltext : 97879.pdf (publisher's version ) (Open Access)BACKGROUND: Pediatric oncology has a strong research culture. Most pediatric oncologists are investigators, involved in clinical care as well as research. As a result, a remarkable proportion of children with cancer enrolls in a trial during treatment. This paper discusses the ethical consequences of the unprecedented integration of research and care in pediatric oncology from the perspective of parents and physicians. METHODOLOGY: An empirical ethical approach, combining (1) a narrative review of (primarily) qualitative studies on parents' and physicians' experiences of the pediatric oncology research practice, and (2) comparison of these experiences with existing theoretical ethical concepts about (pediatric) research. The use of empirical evidence enriches these concepts by taking into account the peculiarities that ethical challenges pose in practice. RESULTS: Analysis of the 22 studies reviewed revealed that the integration of research and care has consequences for the informed consent process, the promotion of the child's best interests, and the role of the physician (doctor vs. scientist). True consent to research is difficult to achieve due to the complexity of research protocols, emotional stress and parents' dependency on their child's physician. Parents' role is to promote their child's best interests, also when they are asked to consider enrolling their child in a trial. Parents are almost never in equipoise on trial participation, which leaves them with the agonizing situation of wanting to do what is best for their child, while being fearful of making the wrong decision. Furthermore, a therapeutic misconception endangers correct assessment of participation, making parents inaccurately attribute therapeutic intent to research procedures. Physicians prefer the perspective of a therapist over a researcher. Consequently they may truly believe that in the research setting they promote the child's best interests, which maintains the existence of a therapeutic misconception between them and parents. CONCLUSION: Due to the integration of research and care, their different ethical perspectives become intertwined in the daily practice of pediatric oncology. Increasing awareness of what this means for the communication between parents and physicians is essential. Future research should focus on efforts that overcome the problems that the synchronicity of research and care evokes