Getting the Phenotypes Right: An Essential Ingredient for Understanding Aetiological Mechanisms Underlying Persistent Violence and Developing Effective Treatments

In order to reduce societal levels of violence, it is essential to advance understanding of the neurobiological mechanisms involved in initiating and maintaining individual patterns of physical aggression. New technologies such as Magnetic Resonance Imagining and analyses of DNA provide tools for identifying these mechanisms. The reliability and validity of the results of studies using these tools depend not only on aspects of the technology, but also on the methodological rigour with which the studies are conducted, particularly with respect to characterizing the phenotype. The present article discusses five challenges confronting scientists who aim to advance understanding of the neurobiological mechanisms associated with persistent violence. These challenges are: (1) to develop evidence-based hypotheses and to design studies that test alternate hypotheses; (2) to recruit samples that are homogeneous with respect to variables that may be linked to neurobiological mechanisms underpinning violent behaviour; (3) to use reliable and valid measures in order to fully characterize participants so that the external validity of the results is evident; (4) to restrict the range of age of participants so as not to confuse developmental change with group differences; and (5) to take account of sex. Our goal is to contribute to elevating methodological standards in this new field of research and to thereby improve the validity of results and move closer to finding effective ways to reduce violence

Current practice in bicistronic ires reporter use: A systematic review

Bicistronic reporter assays have been instrumental for transgene expression, understanding of internal ribosomal entry site (IRES) translation, and identification of novel cap-independent translational elements (CITE). We observed a large methodological variability in the use of bicistronic reporter assays and data presentation or normalization procedures. Therefore, we systematically searched the literature for bicistronic IRES reporter studies and analyzed methodological details, data visualization, and normalization procedures. Two hundred fifty-seven publications were identified using our search strategy (published 1994–2020). Experimental studies on eukaryotic adherent cell systems and the cell-free translation assay were included for further analysis. We evaluated the following methodological details for 176 full text articles: the bicistronic reporter design, the cell line or type, transfection methods, and time point of analyses post-transfection. For the cell-free translation assay, we focused on methods of in vitro transcription, type of translation lysate, and incubation times and assay temperature. Data can be presented in multiple ways: raw data from individual cistrons, a ratio of the two, or fold changes thereof. In addition, many different control experiments have been suggested when studying IRES-mediated translation. In addition, many different normalization and control experiments have been suggested when studying IRES-mediated translation. Therefore, we also categorized and summarized their use. Our unbiased analyses provide a representative overview of bicistronic IRES reporter use. We identified parameters that were reported inconsistently or incompletely, which could hamper data reproduction and interpretation. On the basis of our analyses, we encourage adhering to a number of practices that should improve transparency of bicistronic reporter data presentation and improve methodological descriptions to facilitate data replication

Vertical Transmission of Rift Valley Fever Virus Without Detectable Maternal Viremia

Abstract Rift Valley fever virus (RVFV) is a zoonotic bunyavirus that causes abortions in domesticated ruminants. Sheep breeds exotic to endemic areas are reportedly the most susceptible to RVFV infection. Within the scope of a risk assessment program of The Netherlands, we investigated the susceptibility of a native breed of gestating sheep to RVFV infection. Ewes were infected experimentally during the first, second, or third trimester of gestation. Mortality was high among ewes that developed viremia. Four of 11 inoculated ewes, however, did not develop detectable viremia nor clinical signs and did not seroconvert for immunoglobulin G (IgG) or IgM antibodies. Surprisingly, these ewes were found to contain viral RNA in maternal and fetal organs, and the presence of live virus in fetal organs was demonstrated by virus isolation. We demonstrate that RVFV can be transmitted vertically in the absence of detectable maternal viremia

Quantifying Rift Valley fever virus transmission efficiency in a lamb-mosquito-lamb model

Rift Valley fever virus (RVFV) is a (re)emerging mosquito-borne pathogen impacting human and animal health. How RVFV spreads through a population depends on population-level and individual-level interactions between vector, host and pathogen. Here, we estimated the probability for RVFV to transmit to naive animals by experimentally exposing lambs to a bite of an infectious mosquito, and assessed if and how RVFV infection subsequently developed in the exposed animal. Aedes aegypti mosquitoes, previously infected via feeding on a viremic lamb, were used to expose naive lambs to the virus. Aedes aegypti colony mosquitoes were used as they are easy to maintain and readily feed in captivity. Other mosquito spp. could be examined with similar methodology. Lambs were exposed to either 1-3 (low exposure) or 7-9 (high exposure) infectious mosquitoes. All lambs in the high exposure group became viremic and showed characteristic signs of Rift Valley fever within 2-4 days post exposure. In contrast, 3 out of 12 lambs in the low exposure group developed viremia and disease, with similar peak-levels of viremia as the high exposure group but with some heterogeneity in the onset of viremia. These results suggest that the likelihood for successful infection of a ruminant host is affected by the number of infectious mosquitoes biting, but also highlights that a single bite of an infectious mosquito can result in disease. The per bite mosquito-to-host transmission efficiency was estimated at 28% (95% confidence interval: 15 - 47%). We subsequently combined this transmission efficiency with estimates for life traits of Aedes aegypti or related mosquitoes into a Ross-McDonald mathematical model to illustrate scenarios under which major RVFV outbreaks could occur in naïve populations (i.e., R0 >1). The model revealed that relatively high vector-to-host ratios as well as mosquitoes feeding preferably on competent hosts are required for R0 to exceed 1. Altogether, this study highlights the importance of experiments that mimic natural exposure to RVFV. The experiments facilitate a better understanding of the natural progression of disease and a direct way to obtain epidemiological parameters for mathematical models

Pharmacotherapeutic intervention in impulsive preschool children: The need for a comprehensive therapeutic approach

Impulsive and aggressive behaviour symptoms often are serious problems in children, even already at preschool age. Thus, effective treatment approaches are requested. In this comment pharmacotherapeutic treatment approaches, first of all risperidone, their limitations and alternative psychotherapeutic approaches are outlined

Effectiveness of simulation training and assessment of PICU nurses' resuscitation skills: A mixed methods study from the Netherlands

Purpose: The quality of resuscitation and effective leadership are decisive for the outcome of a resuscitation. Nurses are usually the first responders upon cardiac arrest. Therefore, we started the “proficiency check” project, which aims to improve nurses' resuscitation and teamwork skills. This article describes the effectiveness of the proficiency check and nurses' experiences with it. Design and methods: This study was done among intensive care nurses working on a pediatric ICU (PICU) in the Netherlands. It was designed as a mixed-methods study combining a quantitative and a qualitative approach. Quantitative data were obtained through a pre-posttest comparison of nurses' resuscitation and teamwork skills, in a simulation setting. Qualitative data on nurses' experiences were collected through semi-structured individual interviews. Results: Both resuscitation and teamwork skills improved significantly. In 39 nurses (32%), the improvement of both resuscitation and teamwork skills after the intervention was large (effect size >0.8). The experiences of nu

A study protocol to develop and test an e‐health intervention in follow‐up service for intensive care survivors' relatives

Background: The negative impact on long-term health-related outcomes among relatives of critically ill patients in the intensive care unit (ICU) has been well described. High-quality ICU specialized follow-up care, which is easily accessible with digital innovation and which is designed by and with relevant stakeholders (i.e., ICU patients' relatives and nurses), should be considered to reduce these impairments in the psychological and social domains. Aim: The programme's aim is to develop and test an e-health intervention in a follow-up service to support ICU patients' relatives. Here, the protocol for the overall study programme will be described. Study Design: The overall study comprises a mixed-methods, multicentre research design with qualitative and quantitative study parts. The study population is ICU patients' adult relatives and ICU nurses. The main outcomes are the experiences of these stakeholders with the newly developed e-health intervention. There will be no predefined selection based on age, gender, and level of education to maximize diversity throughout the study programme. After the participants provide informed consent, data will be gathered through focus groups (n = 5) among relatives and individual interviews (n = 20) among nurses exploring the needs and priorities of a digital follow-up service. The findings will be explored further for priority considerations among members of the patient/relative organization (aiming n = 150), which will serve as a basis for digital prototypes of the e-health intervention. Assessment of the intervention will be followed during an iterative process with investigator-developed questionnaires. Finally, symptoms of anxiety and depression will be measured with the 14-item Dutch version of the ‘Hospital Anxiety and Depression Scale’, and symptoms of posttraumatic stress will be measured with the 21-item Dutch version of the ‘Impact of Events Scale-Revised’ to indicate the effectiveness of digital support among ICU patients' relatives. Relevance to Clinical Practice: The e-health intervention to be developed during this research programme can possibly bridge the gap in integrated ICU follow-up care by providing relevant information, self-monitoring and stimulating self-care among ICU patients' relatives