Loss of the acetate switch in <i>Vibrio vulnificus</i> enhances predation defence against <i>Tetrahymena pyriformis</i>.

Vibrio vulnificus is an opportunistic human pathogen and autochthonous inhabitant of coastal marine environments, where the bacterium is under constant predation by heterotrophic protists or protozoans. As a result of this selection pressure, genetic variants with anti-predation mechanisms are selected for and persist in the environment. Such natural variants may also be pathogenic to animal or human hosts, making it important to understand these defence mechanisms. To identify anti-predator strategies, thirteen V. vulnificus strains of different genotypes isolated from diverse environments were exposed to predation by the ciliated protozoan, Tetrahymena pyriformis, and only strain ENV1 was resistant to predation. Further investigation of the cell-free supernatant showed that ENV1 acidifies the environment by the excretion of organic acids, which is toxic to T. pyriformis. As this predation resistance was dependent on the availability of iron, transcriptomes of V. vulnificus in iron-replete and iron-deplete conditions were compared. This analysis revealed that ENV1 ferments pyruvate and the resultant acetyl-CoA leads to acetate synthesis under aerobic conditions, a hallmark of overflow metabolism. The anaerobic respiration global regulator, arcA, was upregulated when iron was available. An ΔarcA deletion mutant of ENV1 accumulated less acetate and importantly, was sensitive to grazing by T. pyriformis. Based on the transcriptome response and quantification of metabolites, we conclude that ENV1 has adapted to overflow metabolism and has lost a control switch that shifts metabolism from acetate excretion to acetate assimilation, enabling it to excrete acetate continuously. We show that overflow metabolism and the acetate switch contribute to prey-predator interactions. Importance Bacteria in the environment, including Vibrio spp., interact with protozoan predators. To defend against predation, bacteria evolve anti-predator mechanisms ranging from changing morphology, biofilm formation and secretion of toxins or virulence factors. Some of these adaptations may result in strains that are pathogenic to humans. Therefore, it is important to study predator defence strategies of environmental bacteria. V. vulnificus thrives in coastal waters and infects humans. Very little is know about the defence mechanisms V. vulnificus expresses against predation. Here we show that a V. vulnificus strain (ENV1) has rewired the central carbon metabolism enabling the production of excess organic acid that is toxic to the protozoan predator, T. pyriformis. This is a previously unknown mechanism of predation defence that protects against protozoan predators

National guidelines for cognitive assessment and rehabilitation of Iranian traumatic brain injury patients

Background: Individuals with moderate to severe traumatic brain injury (TBI) often have prolonged cognitive impairments, resulting in long-term problems with their real-life activities. Given the urgent need for evidence-based recommendations for neuropsychological management of Iranian TBI patients, the current work aimed to adapt eligible international guidelines for cognitive assessment and rehabilitation of the TBI patients in Iran. Methods: The project was led by an executive committee, under the supervision of the Iranian Ministry of Health and Medical Education (MOHME). Following a systematic literature search and selection process, four guidelines were included for adaptation. Clinical recommendations of the source guidelines were tabulated as possible clinical scenarios for 90 PICO clinical questions covering all relevant phases of care. After summing up the scenarios, our initial list of recommendations was drafted according to the Iranian patients� conditions. The final decision-making, with the contribution of a national interdisciplinary panel of 37 experts from across the country, was conducted in two rounds using online and offline survey forms (Round 1), and face-to-face and telephone meetings (Round 2). Results: A total of 63 recommendations in six sections were included in the final list of recommendations, among which 24 were considered as key recommendations. In addition, some of the recommendations were identified as fundamental, meaning that proper implementation of the other recommendations is largely dependent on their implementation. Conclusion: Iranian health policy makers and rehabilitation program managers are recommended to address some fundamental issues to provide the necessary infrastructure to set up an efficient cognitive rehabilitation service system. © 2020 Academy of Medical Sciences of I.R. Iran. All rights reserved

Development and psychometric evaluation of "Quality of Life Scale for Asthmatic Children” (QOLSAC)

Background and aimAsthma is a chronic condition affecting on quality of life (QOL) of afflicted children and their families. Nurses and other healthcare workers need a valid and reliable tool to mesure these effects. The aim of this study was to Development and psychometric evaluation of "Quality of Life Scale for Asthmatic Children” (QOLSAC).  Materials and methodsThis research is a methodological study. A review of literature and semistructured interviews with 13 asthmatic children were carried out to develop 81 statements of “Quality of Life Scale for Asthmatic Children (QOLSAC).”The content of the scale were then validated by asking 30 professionals in pediatric medicine and nursing, asthma, tool development and QOL based on relatedness, clarity and simpleness. Statements with 75% validity or more were retained. Face validity of the scale was also identified. Construct (factor analysis) and criterion validitieswere identified by distributing the scale to 136 asthmatic children and comparing with Kindel’s QOL questionnaire respectively. Internal consistency (Cronbach’s α) and stability (test-retest) measurements were performed for the reliability of the scale. FindingsFactor analysis showed 5 domains (factors) in the scale and criterion validity revealed 0.89 correlation between the 2 tools. The range of Cronbach’s α (coefficient of correlation) in the 5 domains was between 0.81 and 0.92 and test-retest measurements indicated 0.93-0.98 correlations in the domains. ConclusionThe results showed that QOLSAC with 61 statements is valid and reliable, using Likert measurement scale. With respect to the importance of this scale, applying it to assess the quality of life of asthmatic children is recommended.  Keywords: Scale development, Psychometric evaluation, Quality of life, Asthmatic children. *Corresponding Author: Dr. Farideh, Yaghmaei. Dept. of Community Health Nursing, Faculty of Nursing and Midwifery, Shahid Beheshti University of Medical Sciences, Tehran, Iran E-mail: [email protected]

Dynamic compartmental models for large multi-objective landscapes and performance estimation

International audienceDynamic Compartmental Models are linear models inspired by epidemiology models to study Multi- and Many-Objective Evolutionary Algorithms dynamics. So far they have been tested on small MNK-Landscapes problems with 20 variables and used as a tool for algorithm analysis, algorithm comparison, and algorithm configuration assuming that the Pareto optimal set is known. In this paper, we introduce a new set of features based only on when non-dominated solutions are found in the population, relaxing the assumption that the Pareto optimal set is known in order to use Dynamic Compartment Models on larger problems. We also propose an auxiliary model to estimate the hypervolume from the features of population dynamics that measures the changes of new non-dominated solutions in the population. The new features are tested by studying the population changes on the Adaptive ϵ-Sampling ϵ-Hood while solving 30 instances of a 3 objective, 100 variables MNK-landscape problem. We also discuss the behavior of the auxiliary model and the quality of its hypervolume estimations

Reusability for Trust and Reputation Systems

Part 2: Full PapersInternational audienceReputation systems have been extensively explored in various disciplines and application areas. A problem in this context is that the computation engines applied by most reputation systems available are designed from scratch and rarely consider well established concepts and achievements made by others. Thus, approved models and promising approaches may get lost in the shuffle. In this work, we aim to foster reuse in respect of trust and reputation systems by providing a hierarchical component taxonomy of computation engines which serves as a natural framework for the design of new reputation systems. In order to assist the design process we, furthermore, provide a component repository that contains design knowledge on both a conceptual and an implementation level

Diagnostic approach to the patients with suspected primary immunodeficiency

Background and Objective: Primary immunodeficiency diseases (PIDs) are a group of more than 350 disorders affecting distinct components of the innate and adaptive immune systems. In this review, the classic and advanced stepwise approach towards the diagnosis of PIDs are simplified and explained in detail. Results: Susceptibility to recurrent infections is the main hallmark of almost all PIDs. However, non-infectious complications attributable to immune dysregulation presenting with lymphoproliferative and/or autoimmune disorders are not uncommon. Moreover, PIDs could be associated with misleading presentations including allergic manifestations, enteropathies, and malignancies. Conclusion: Timely diagnosis is the most essential element in improving outcome and reducing the morbidity and mortality in PIDs. This wouldn�t be possible unless the physicians keep the diagnosis of PID in mind and be sufficiently aware of the approach to these patients. © 2020 Bentham Science Publishers