State Space Exploration of Spatially Organized Populations of Agents

International audienceIn this paper, we aim at modeling and analyzing the behavior of a spatial population of agents through an exploration of their state space. Agents are localized on a dynamic graph and they have internal states. They interact with an environment. The evolution of the agents and of the environment is specified by a set of rules. The framework is carefully designed to enable the construction of a global state space that can be automatically build and analyzed. The formalism, called IRNs for integrated regulatory networks, may be seen as an extension of logical regulatory networks (à la Thomas) developed in systems biology with spatial information and generalized to use arbitrary data values and update functions of this values. This thus allows to model systems with multiple agents that may be located on a varying spatial structure, may store and update local information, may depend on varying global information and may communicate in their neighborhood. A model of such a system can be defined as an IRN, and then analyzed using model-checking to asses its properties. This paper sketches the modeling framework and its semantics. We show how IRN may be used for the modeling of a population of simple agents, the automatic analysis of various reachability properties and the use of symmetries to reduce the size of the state space

Hepatitis E virus infection as a new probable cause of de novo membranous nephropathy after kidney transplantation.

International audienceHepatitis E virus (HEV) has been identified as a cause of chronic viral hepatitis in immunocompromised patients. Some glomerular diseases were found to be associated with this infection. We report the first case, to our knowledge, of a kidney transplant recipient who developed an HEV infection and de novo membranous nephropathy (MN) concomitantly. The patient displayed a hepatic cytolysis first and a nephrotic syndrome occurred 3 months later. HEV infection was diagnosed upon positive polymerase chain reaction on plasma and stool samples, and renal allograft biopsy revealed de novo MN. Typical causes of MN were definitively excluded. A 3-month course of ribavirin monotherapy allowed the patient to mount a sustained viral response that was rapidly followed by complete remission of the nephrotic syndrome. The chronology of the onset and remission of both diseases is highly suggestive of a causal relationship between hepatitis E and MN

Blood Purif

Background: An altered immune response and decreased vaccine response are observed in patients with chronic renal failure. A preliminary study of 15 non-immunised patients, despite appropriate previous hepatitis B vaccination, showed a 60% seroconversion rate after 3 months of dialysis with a polymethylmethacrylate (PMMA) membrane. This response was associated with circulating soluble CD40 (CD40s) decrease, a natural inhibitor of the humoral immune response. The aim of the study is to confirm these results in a randomised study. Methods: We conducted a multicentre randomised intention-to-treat superiority clinical trial comparing polysulfone and a PMMA membrane in 2 parallel patient groups. The primary end point was the vaccine response rate, as defined by an anti-HBs antibodies titre of >10 IU/L, 1 month after the last vaccination with a double dose of Engerix B20®, performed at weeks 12, 16, 20, and 36. Results: Twenty-five patients were randomised and included in an intention-to-treat analysis. They were dialysed on polysulfone (n = 11) or PMMA (n = 14) for 40 weeks. Fifty percent of the PMMA patients versus 54.5% of the polysulfone patients achieved seroconversion (p = 1.00). The median anti-HBs antibody titre in responders at week 40 was 496 (92–750) versus 395 (43–572) UI/mL for PMMA and polysulfone, respectively (p = 0.46). The median CD40s titre at week 12 was 306 (193–448) versus 491 (281–515) pg/mL (p = 0.21). The CD40s median variation between week 0 and week 12 was 5 (–105 to 90) versus 64 (–63 to 123) pg/mL (p = 0.55). The CD40s level at week 12 in non-responders was slightly inferior to that of the responders: median 193 (168–331) versus 413 (281–512) pg/mL (p = 0.08). Conclusion: We did not observe a better vaccine response with the PMMA membrane compared to high-flux polysulfone. The PMMA membrane did not decrease the CD40s more than the polysulfone membrane probably because the titre was previously low in the 2 groups

IAOOS (Ice - Atmosphere - Arctic Ocean Observing System, 2011-2019)

6th International Workshop on Sea-Ice Modelling and Data Assimilation, 2014 September 15-16, Toulouse, FranceInternational audienceThe key to documenting and understanding change in the Arctic is continuous monitoring. The high cost of Arctic operations thus makes observationsby satellite or with long-endurance, refurbishable, autonomous platforms a cost effective solution to continuously observe on-going changes in nearreal-time. IAOOS (Ice Atmosphere Ocean Observing System, http://www.iaoos-equipex.upmc.fr, http://iaoos.ipev.fr/) is a nine-year France-fundedproject (2011-2019), developed by LOCEAN and LATMOS, which objective is to provide and maintain an integrated observing system over the ArcticOcean that collects synoptic and near real time information related to the state of the atmosphere, the snow, the sea-ice and the ocean

Diversité des prises en charge hospitalières de l'anorexie mentale en psychiatrie en France

International audienceBackground: Hospitalization is rare in anorexia nervosa (AN) and local application of indications is heterogeneous. However, no study has evaluated the effect of these different treatment modalities on the mean length of stay. Our objective was to describe the context and modalities of a wide range of hospital care programs offered to patients with anorexia nervosa in eleven specialized French psychiatric centers for patients from childhood to adulthood. This work was carried out within the framework of the EVHAN (Evaluation of Hospitalization for AN, Eudract number: 2007-A01110-53, registered in Clinical trials) research program. The EVHAN program comprises five main lines: weight objectives at discharge, the practice or not of a separation period, the use of clear nutritional dietary objectives (cognitive/behavioral), the intensity of family involvement in treatment, and the existence or absence of a stabilization phase before ending inpatient treatment. These main lines will make it possible to study the impact of treatment modalities on the future of patients in the short and medium term (at discharge and at 1-year follow-up). Methods: The eleven centers are located in France (Bordeaux, Nantes, Paris and Ile-de-France, Rouen and Saint-Étienne). Various staff members (psychiatrists, somatic doctors, nurses, dieticians, psychologists) from each center were interviewed using a semi-structured questionnaire. Data on operating modalities and context of care were collected and analyzed. Results: Four of the eleven centers were exclusively child/adolescent centers, and seven of 11 were adolescent (from 11, 13 or 16 years) and young adult centers. All centers offered a graduated approach from outpatient to full hospitalization. The majority had a number of beds allocated for patients with eating disorders. The criteria for hospitalization were homogeneous with respect to somatic and/or psychic severity prefiguring the consensus criteria defined by the French Health Authority (HAS) in 2010. Child/adolescent units used the weight curve to set weight objectives at discharge (between the 10th and 50th percentiles). Most adult units used weight objectives at discharge corresponding to a body mass index between 17 and 20 kg/m2. Nine centers used a written or oral care contract. One unit did not separate the patient from her/his usual environment, the others had a practice gradient of partial separation and total separation times. These were either short, lasting a maximum of 3 weeks, or long, lasting more than 3 weeks. Conversely, patients were not isolated within the unit, and benefited from a rich social life, depending on her/his physical condition. The patient's family was in contact with the team and fully supported. The longest periods of separation involved adolescents and adults. Nutritional support varied from a group approach (meals in the dining room, standardized meals of the care center) to very individualized approaches within a specific framework. All the units reported meeting with families at least once during the hospitalization; with the patient's parents for child/adolescent patients and/or unmarried patients and with the husband/wife for married patients. The majority of the centers requested a phase of weight stabilization, whatever the age before hospital discharge. Conclusion: There is international and national consensus regarding the indications for hospitalization, and the main lines of multidisciplinary care to be developed within this framework. However, local application of these indications was heterogeneous resulting in diverse modalities of hospital care for anorexia nervosa in France. Specialized teams have developed management strategies arising from their “team culture”. The complexity of the anorexic pathology, due to the psyche-soma intrication and the diversity of age groups, highlights the complexity of care available. The impact of this diversity of hospital care on patient outcomes will be studied as a result of this work

Caregivers in anorexia nervosa: is grief underlying parental burden?

AUTEURS : The members of the EVHAN GroupInternational audiencePurpose: Anorexia Nervosa (AN) is a severe chronic disorder and parents’ experience of caregiving is usually marked by emotional distress and burden. Severe chronic psychiatric disorders are known to be linked with the concept of grief. Grief has not been investigated in AN. The aim of this study was to explore parents’ and adolescents’ characteristics that may be related to parental burden and grief in AN, and the link between these two dimensions. Methods: Eighty mothers, 55 fathers and their adolescents (N = 84) hospitalized for AN participated in this study. Evaluations of clinical characteristics of the adolescent’s illness were completed, as well as self-evaluations of adolescent and parental emotional distress (anxiety, depression, alexithymia). Levels of parental burden were evaluated with the Experience of Caregiving Inventory and levels of parental grief with the Mental Illness Version of the Texas Revised Inventory of Grief. Results: Main findings indicated that the burden was higher in parents of adolescents with a more severe AN; fathers’ burden was also significantly and positively related to their own level of anxiety. Parental grief was higher when adolescents’ clinical state was more severe. Paternal grief was related to higher anxiety and depression, while maternal grief was correlated to higher alexithymia and depression. Paternal burden was explained by the father’s anxiety and grief, maternal burden by the mother’s grief and her child’s clinical state. Conclusion: Parents of adolescents suffering from AN showed high levels of burden, emotional distress and grief. These inter-related experiences should be specific targets for intervention aimed at supporting parents. Our results support the extensive literature on the need to assist fathers and mothers in their caregiving role. This in turn may improve both their mental health and their abilities as caregivers of their suffering child. Level of evidence: Level III: Evidence obtained from cohort or case-control analytic studies

Low incidence of SARS-CoV-2, risk factors of mortality and the course of illness in the French national cohort of dialysis patients

International audienceThe aim of this study was to estimate the incidence of COVID-19 disease in the French national population of dialysis patients, their course of illness and to identify the risk factors associated with mortality. Our study included all patients on dialysis recorded in the French REIN Registry in April 2020. Clinical characteristics at last follow-up and the evolution of COVID-19 illness severity over time were recorded for diagnosed cases (either suspicious clinical symptoms, characteristic signs on the chest scan or a positive reverse transcription polymerase chain reaction) for SARS-CoV-2. A total of 1,621 infected patients were reported on the REIN registry from March 16th, 2020 to May 4th, 2020. Of these, 344 died. The prevalence of COVID-19 patients varied from less than 1% to 10% between regions. The probability of being a case was higher in males, patients with diabetes, those in need of assistance for transfer or treated at a self-care unit. Dialysis at home was associated with a lower probability of being infected as was being a smoker, a former smoker, having an active malignancy, or peripheral vascular disease. Mortality in diagnosed cases (21%) was associated with the same causes as in the general population. Higher age, hypoalbuminemia and the presence of an ischemic heart disease were statistically independently associated with a higher risk of death. Being treated at a selfcare unit was associated with a lower risk. Thus, our study showed a relatively low frequency of COVID-19 among dialysis patients contrary to what might have been assumed