Predicting sepsis using deep learning across international sites: a retrospective development and validation study

Background

When sepsis is detected, organ damage may have progressed to irreversible stages, leading to poor prognosis. The use of machine learning for predicting sepsis early has shown promise, however international validations are missing.

Methods

This was a retrospective, observational, multi-centre cohort study. We developed and externally validated a deep learning system for the prediction of sepsis in the intensive care unit (ICU). Our analysis represents the first international, multi-centre in-ICU cohort study for sepsis prediction using deep learning to our knowledge. Our dataset contains 136,478 unique ICU admissions, representing a refined and harmonised subset of four large ICU databases comprising data collected from ICUs in the US, the Netherlands, and Switzerland between 2001 and 2016. Using the international consensus definition Sepsis-3, we derived hourly-resolved sepsis annotations, amounting to 25,694 (18.8%) patient stays with sepsis. We compared our approach to clinical baselines as well as machine learning baselines and performed an extensive internal and external statistical validation within and across databases, reporting area under the receiver-operating-characteristic curve (AUC).

Findings

Averaged over sites, our model was able to predict sepsis with an AUC of 0.846 (95% confidence interval [CI], 0.841-0.852) on a held-out validation cohort internal to each site, and an AUC of 0.761 (95% CI, 0.746-0.770) when validating externally across sites. Given access to a small fine-tuning set (10% per site), the transfer to target sites was improved to an AUC of 0.807 (95% CI, 0.801-0.813). Our model raised 1.4 false alerts per true alert and detected 80% of the septic patients 3.7 h (95% CI, 3.0-4.3) prior to the onset of sepsis, opening a vital window for intervention.

Interpretation

By monitoring clinical and laboratory measurements in a retrospective simulation of a real-time prediction scenario, a deep learning system for the detection of sepsis generalised to previously unseen ICU cohorts, internationally.

Funding

This study was funded by the Personalized Health and Related Technologies (PHRT) strategic focus area of the ETH domain.

First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment

The LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t. A profile-likelihood ratio analysis shows the data to be consistent with a background-only hypothesis, setting new limits on spin-independent WIMP-nucleon, spin-dependent WIMP-neutron, and spin-dependent WIMP-proton cross sections for WIMP masses above 9  GeV/c^{2}. The most stringent limit is set for spin-independent scattering at 36  GeV/c^{2}, rejecting cross sections above 9.2×10^{-48}  cm at the 90% confidence level.

AB1120 PSYCHOLOGICAL ASSESSMENT IN PATIENTS WITH CHRONIC RHEUMATIC, SYSTEMIC AUTOIMMUNE, OR AUTOINFLAMMATORY DISEASES PRESENTED WITH COVID-19: THE MentCOVRMD STUDY

Background

The COVID-19 pandemic has raised concerns about its psychological effects. Sleep disturbances, anxiety and/or depressive symptoms, post-traumatic stress symptoms have been reported in general population. Patients with chronic rheumatism, systemic autoimmune disease or auto-inflammatory disease, due to immunosuppression, are at risk of severe forms of infection. Currently, there is little information on psychological impact of the pandemic on the mental health of these more vulnerable patients.

Objectives

To compare psychological assessment between patients with chronic rheumatic, autoimmune and/or autoinflammatory diseases who presented with COVID-19 infection between March and September 2020, first wave of French pandemic, and patients with same diseases who did not presented with infection to date.

Methods

The MentCOVRMD study was a multicenter descriptive study. Cases were patients with chronic rheumatic, autoimmune and/or autoinflammatory diseases from the French RMD cohort who presented COVID-19 infection between March and September 2020. Controls were patients with same diseases who did not develop infection. The study is registered in Clinical Trials under number 2020-A02058-31.

For participants, following criteria were collected: demographics (age, gender, smoking status); psychological assessment questionnaires: Insomnia Severity Index (ISI); Post-traumatic stress disorder (PTSD) checklist; Patient Health Questionnaire (PHQ9) Depression; Generalized Anxiety Disorder (GAD7) Anxiety; Patient Health Questionnaire-15 (PHQ-15) and Somatic Symptom Disorder (SSD)-12.

Results

Between February and December 2021, 60 cases (46 (76.7%) women), median age 52.0 (39.0; 63.0) were included, of which 15 (25%) had been hospitalized during infection, and 169 controls (148 (87.6%) women), median age of 52.0 (38.0; 63.0). There were more smokers in the group of cases 12 (20%) than controls 14 (9.1%) (p=0.028) as well as more cases on ARA2 treatment (8 (13.3%)) than controls (7 (4.5%)) (p=0.035) with no statistically significant difference in others comorbidities or treatments.

There was no statistically difference concerning the ISI scores between cases (11.83 ± 7.31) of which 60% had sleep disorders and controls (11.64 ± 6.82) of which 70.4% had sleep disorders. There was no statistically significant difference in PTSD scores of 15.5 (5.0 to 28.0) for cases and 18.0 (8.0 to 35.0) for controls, of which respectively 12 (20%) had values indicating possible PTSD for cases and 50 (29.6%) for controls. There was no statistically significant difference in PHQ-9 scores (5.5 (1.5 to 11.0)) of which 50% had depressive symptoms and controls (6.0 (2.0 to 11.0)) of which 54.5% had symptoms. There was no statistically significant difference in GAD-7 scores (3.5 (0.0 to 8.0)) of which 40% had anxiety symptoms and controls (4.0 (0.0 to 8.0)) of which 43.2% had symptoms. There was no statistically significant difference in PHQ-15 scores (11.4 ± 6.7), 85% of whom reported presence of symptoms, and controls (10.9 ± 6.2), 82.3% of whom reported symptoms. There was no statistically significant difference in SSD scores between cases (17.7 ± 10.9) and controls (18.4 ± 10.9).

There was a statistically significant difference in reported VAS scores of pain related to inflammatory rheumatism in cases with a median of 4.5 (3.0 to 6. 0) compared to controls with a median of 4.0 (1.0 to 6.0) (p=0.011).

There was no statistically significant difference in any of the psychological assessment scores between the inpatient and outpatient COVID cases.

Conclusion

There was no statistically significant difference between COVID cases and controls in the evaluation of these psychological parameters. Prevalence of all these variables were high in the whole study population, testifying to the need to manage these psychological aspects for patients with chronic rheumatisms, autoimmune and/or autoinflammatory diseases.

Disclosure of Interests

None declared

The life cycle-dependent transcriptional profile of the obligate intracellular amoeba symbiont Amoebophilus asiaticus

Free-living amoebae often harbor obligate intracellular bacterial symbionts. Amoebophilus (A.) asiaticus is a representative of a lineage of amoeba symbionts in the phylum Bacteroidota. Here, we analyse the transcriptome of A. asiaticus strain 5a2 at four time points during its infection cycle and replication within the Acanthamoeba host using RNA sequencing. Our results reveal a dynamic transcriptional landscape throughout different A. asiaticus life cycle stages. Many intracellular bacteria and pathogens utilize eukaryotic-like proteins (ELPs) for host cell interaction and the A. asiaticus 5a2 genome shows a particularly high abundance of ELPs. We show the expression of all genes encoding ELPs and found many ELPs to be differentially expressed. At the replicative stage of A. asiaticus, ankyrin repeat proteins and tetratricopeptide/Sel1-like repeat proteins were upregulated. At the later time points, high expression levels of a type 6 secretion system that likely prepares for a new infection cycle after lysing its host, were found. This study reveals comprehensive insights into the intracellular lifestyle of A. asiaticus and highlights candidate genes for host cell interaction. The results from this study have implications for other intracellular bacteria such as other amoeba-associated bacteria and the arthropod symbionts Cardinium forming the sister lineage of A. asiaticus.

Accuracy of registration techniques and vascular imaging modalities in fusion imaging for aortic endovascular interventions: a phantom study

Background

This study aimed to assess the error of different registration techniques and imaging modalities for fusion imaging of the aorta in a standardized setting using a anthropomorphic body phantom.

Materials and methods

A phantom with the 3D printed vasculature of a patient suffering from an infrarenal aortic aneurysm was constructed. Pulsatile flow was generated via an external pump. CTA/MRA of the phantom was performed, and a virtual 3D vascular model was computed. Subsequently, fusion imaging was performed employing 3D-3D and 2D-3D registration techniques. Accuracy of the registration was evaluated from 7 right/left anterior oblique c-arm angulations using the agreement of centerlines and landmarks between the phantom vessels and the virtual 3D virtual vascular model. Differences between imaging modalities were assessed in a head-to-head comparison based on centerline deviation. Statistics included the comparison of means ± standard deviations, student’s t-test, Bland-Altman analysis, and intraclass correlation coefficient for intra- and inter-reader analysis.

Results

3D-3D registration was superior to 2D-3D registration, with the highest mean centerline deviation being 1.67 ± 0.24 mm compared to 4.47 ± 0.92 mm. The highest absolute deviation was 3.25 mm for 3D-3D and 6.25 mm for 2D-3D registration. Differences for all angulations between registration techniques reached statistical significance. A decrease in registration accuracy was observed for c-arm angulations beyond 30° right anterior oblique/left anterior oblique. All landmarks (100%) were correctly positioned using 3D-3D registration compared to 81% using 2D-3D registration. Differences in accuracy between CT and MRI were acceptably small. Intra- and inter-reader reliability was excellent.

Conclusion

In the realm of registration techniques, the 3D-3D method proved more accurate than did the 2D-3D method. Based on our data, the use of 2D-3D registration for interventions with high registration quality requirements (e.g., fenestrated aortic repair procedures) cannot be fully recommended. Regarding imaging modalities, CTA and MRA can be used equivalently.

Early Prediction of Sepsis in the ICU Using Machine Learning: A Systematic Review

Background: Sepsis is among the leading causes of death in intensive care units (ICUs) worldwide and its recognition, particularly in the early stages of the disease, remains a medical challenge. The advent of an affluence of available digital health data has created a setting in which machine learning can be used for digital biomarker discovery, with the ultimate goal to advance the early recognition of sepsis. Objective: To systematically review and evaluate studies employing machine learning for the prediction of sepsis in the ICU. Data Sources: Using Embase, Google Scholar, PubMed/Medline, Scopus, and Web of Science, we systematically searched the existing literature for machine learning-driven sepsis onset prediction for patients in the ICU. Study Eligibility Criteria: All peer-reviewed articles using machine learning for the prediction of sepsis onset in adult ICU patients were included. Studies focusing on patient populations outside the ICU were excluded. Study Appraisal and Synthesis Methods: A systematic review was performed according to the PRISMA guidelines. Moreover, a quality assessment of all eligible studies was performed. Results: Out of 974 identified articles, 22 and 21 met the criteria to be included in the systematic review and quality assessment, respectively. A multitude of machine learning algorithms were applied to refine the early prediction of sepsis. The quality of the studies ranged from "poor" (satisfying ≤ 40% of the quality criteria) to "very good" (satisfying ≥ 90% of the quality criteria). The majority of the studies (n = 19, 86.4%) employed an offline training scenario combined with a horizon evaluation, while two studies implemented an online scenario (n = 2, 9.1%). The massive inter-study heterogeneity in terms of model development, sepsis definition, prediction time windows, and outcomes precluded a meta-analysis. Last, only two studies provided publicly accessible source code and data sources fostering reproducibility. Limitations: Articles were only eligible for inclusion when employing machine learning algorithms for the prediction of sepsis onset in the ICU. This restriction led to the exclusion of studies focusing on the prediction of septic shock, sepsis-related mortality, and patient populations outside the ICU. Conclusions and Key Findings: A growing number of studies employs machine learning to optimize the early prediction of sepsis through digital biomarker discovery. This review, however, highlights several shortcomings of the current approaches, including low comparability and reproducibility. Finally, we gather recommendations how these challenges can be addressed before deploying these models in prospective analyses. Systematic Review Registration Number: CRD42020200133.

Topological and kernel-based microbial phenotype prediction from MALDI-TOF mass spectra

MOTIVATION

Microbial species identification based on matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) has become a standard tool in clinical microbiology. The resulting MALDI-TOF mass spectra also harbour the potential to deliver prediction results for other phenotypes, such as antibiotic resistance. However, the development of machine learning algorithms specifically tailored to MALDI-TOF MS-based phenotype prediction is still in its infancy. Moreover, current spectral pre-processing typically involves a parameter-heavy chain of operations without analyzing their influence on the prediction results. In addition, classification algorithms lack quantification of uncertainty, which is indispensable for predictions potentially influencing patient treatment.

RESULTS

We present a novel prediction method for antimicrobial resistance based on MALDI-TOF mass spectra. First, we compare the complex conventional pre-processing to a new approach that exploits topological information and requires only a single parameter, namely the number of peaks of a spectrum to keep. Second, we introduce PIKE, the peak information kernel, a similarity measure specifically tailored to MALDI-TOF mass spectra which, combined with a Gaussian process classifier, provides well-calibrated uncertainty estimates about predictions. We demonstrate the utility of our approach by predicting antibiotic resistance of three clinically highly relevant bacterial species. Our method consistently outperforms competitor approaches, while demonstrating improved performance and security by rejecting out-of-distribution samples, such as bacterial species that are not represented in the training data. Ultimately, our method could contribute to an earlier and precise antimicrobial treatment in clinical patient care.

AVAILABILITY AND IMPLEMENTATION

We make our code publicly available as an easy-to-use Python package under https://github.com/BorgwardtLab/maldi_PIKE.

The neural correlates of the visual consciousness in schizophrenia: an fMRI study

In the current literature, two distinct and opposite models are suggested to explain the consciousness disorders in schizophrenia. The first one suggests that consciousness disorders rely on a low-level processing deficit, when the second model suggests that consciousness disorders rely on disruption in the ability to consciously access information, with preserved unconscious processing. The current study aims to understand the mechanisms associated with visual consciousness disorder in order to pave the road that will settle the debate regarding these hypotheses. During a functional magnetic resonance imaging session, 19 healthy participants (HC) and 15 patients with schizophrenia (SCZ) performed a visual detection task to compare the neural substrates associated with the conscious access to the visual inputs. The visual detection threshold was significantly higher in SCZ than in HC [t(32) = 3.37, p = 0.002]. Whole-brain ANOVA demonstrated that around the visual detection threshold patients with SCZ failed to activate a large network of brain areas compared to HC. (1) During conscious vision, HC engaged more the left cuneus and the right occipital cortex than patients with SCZ, (2) during unconscious vision, HC engaged a large network that patients with SCZ failed to activate, and finally, (3) during the access to consciousness process, patients with SCZ failed to activate the anterior cingulate cortex. These results suggest that the consciousness disorders in schizophrenia rely on specific dysfunctions depending on the consciousness stage. The disorders of the conscious vision are associated with dysfunction of occipital areas while the ones associated with unconscious vision rely on a large widespread network. Finally, the conscious access to the visual inputs is impaired by a dysfunction of the anterior cingulate cortex. The current study suggests that none of the two suggested models can explain consciousness disorders in schizophrenia. We suggest that there is an alternative model supporting that the conscious access to visual inputs is due to a disengagement of the supragenual anterior cingulate during the unconscious processing of the visual inputs associated with a sensory deficit.

Schizophrénie et violence : la nécessité de considérer différents sous-groupes

Il est aujourd’hui clairement établi que les patients souffrant de schizophrénie présente un risque plus élevé de violence que la population générale. Différents facteurs de risque de violence ont été mis en évidence chez ces patients, tels que l’impulsivité, le trouble de personnalité antisociale, les comorbidités addictives. Néanmoins, les études ayant tenté d’identifier le risque de violence des patients schizophrènes ont abouti à des résultats variables. L’hétérogénéité des gestes de violence commis, ainsi que la variabilité des profils de ces patients contribuent certainement à la divergence de ces résultats. Par ailleurs, différents auteurs ont montré que les patients présentant un délire d’identification des personnes constituaient une sous-catégorie de patients à risque de comportements violents, devenant agressifs et violents du fait du thème de leur délire. Cependant, aucune étude n’a exploré l’association entre délire d’identification et type de geste violent. Nous nous sommes donc intéressés à l’étude des caractéristiques cliniques de patients schizophrènes ayant commis des gestes de violence, à partir d’une étude descriptive réalisée sur une population de patients schizophrènes détenus. Nous avons évalué l’intensité des symptômes grâce à la Positive and Negative Symptom Scale (PANSS), la coexistence d’un trouble de personnalité antisociale et les comorbidités addictives grâce au Mini International Neuropsychiatric Interview (MINI). Le niveau d’impulsivité et les comportements violents ont été estimés par la Baratt Impulsivity Scale (BIS) et la MacArthur Community Violence Interview. Enfin, l’existence de troubles de la familiarité, tels que ceux qui caractérisent les délires d’identification des personnes, a été systématiquement recherchée. Notre objectif est, d’une part, d’évaluer de manière systématique les troubles de familiarité des patients schizophrènes, et leur association avec les comportements violents, et d’autre part, d’objectiver l’hétérogénéité des profils des patients schizophrènes ayant commis des gestes de violence.

TRAPP webserver: predicting protein binding site flexibility and detecting transient binding pockets

The TRAnsient Pockets in Proteins (TRAPP) webserver provides an automated workflow that allows users to explore the dynamics of a protein binding site and to detect pockets or sub-pockets that may transiently open due to protein internal motion. These transient or cryptic sub-pockets may be of interest in the design and optimization of small molecular inhibitors for a protein target of interest. The TRAPP workflow consists of the following three modules: (i) TRAPP structure— generation of an ensemble of structures using one or more of four possible molecular simulation methods; (ii) TRAPP analysis—superposition and clustering of the binding site conformations either in an ensemble of structures generated in step (i) or in PDB structures or trajectories uploaded by the user; and (iii) TRAPP pocket—detection, analysis, and visualization of the binding pocket dynamics and characteristics, such as volume, solvent-exposed area or properties of surrounding residues. A standard sequence conservation score per residue or a differential score per residue, for comparing on- and off-targets, can be calculated and displayed on the binding pocket for an uploaded multiple sequence alignment file, and known protein sequence annotations can be displayed simultaneously. The TRAPP webserver is freely available at http://trapp.h-its.org.

Post-Antibiotic Gut Mucosal Microbiome Reconstitution Is Impaired by Probiotics and Improved by Autologous FMT

Probiotics are widely prescribed for prevention of antibiotics-associated dysbiosis and related adverse effects. However, probiotic impact on post-antibiotic reconstitution of the gut mucosal host-microbiome niche remains elusive. We invasively examined the effects of multi-strain probiotics or autologous fecal microbiome transplantation (aFMT) on post-antibiotic reconstitution of the murine and human mucosal microbiome niche. Contrary to homeostasis, antibiotic perturbation enhanced probiotics colonization in the human mucosa but only mildly improved colonization in mice. Compared to spontaneous post-antibiotic recovery, probiotics induced a markedly delayed and persistently incomplete indigenous stool/mucosal microbiome reconstitution and host transcriptome recovery toward homeostatic configuration, while aFMT induced a rapid and near-complete recovery within days of administration. In vitro, Lactobacillus-secreted soluble factors contributed to probiotics-induced microbiome inhibition. Collectively, potential post-antibiotic probiotic benefits may be offset by a compromised gut mucosal recovery, highlighting a need of developing aFMT or personalized probiotic approaches achieving mucosal protection without compromising microbiome recolonization in the antibiotics-perturbed host.

Results of a Search for Sub-GeV Dark Matter Using 2013 LUX Data

The scattering of dark matter (DM) particles with sub-GeV masses off nuclei is difficult to detect using liquid xenon-based DM search instruments because the energy transfer during nuclear recoils is smaller than the typical detector threshold. However, the tree-level DM-nucleus scattering diagram can be accompanied by simultaneous emission of a bremsstrahlung photon or a so-called "Migdal" electron. These provide an electron recoil component to the experimental signature at higher energies than the corresponding nuclear recoil. The presence of this signature allows liquid xenon detectors to use both the scintillation and the ionization signals in the analysis where the nuclear recoil signal would not be otherwise visible. We report constraints on spin-independent DM-nucleon scattering for DM particles with masses of 0.4-5  GeV/c^{2} using 1.4×10^{4}  kg day of search exposure from the 2013 data from the Large Underground Xenon (LUX) experiment for four different classes of mediators. This analysis extends the reach of liquid xenon-based DM search instruments to lower DM masses than has been achieved previously.

[General medical care in French psychiatric units for inmates: A national survey]

OBJECTIVES

The UHSA (UHSA) are French psychiatric units for inmates which admit detainees suffering from a psychiatric disorder requiring full-time hospital care. Non-psychiatric pathologies are overrepresented in patients with psychiatric disorders but also in detainees. As a result, patients hospitalized in UHSA are largely exposed to non-psychiatric conditions, and exploring the organization of general medical care for these patients appears very relevant. The aim of this study is to review the general medical care in all French UHSA.

METHODS

A descriptive study was carried out through a survey of the nine facilities.

RESULTS

All UHSA benefit from the intervention of a general practitioner. The physical clinical examination, the biological assessment and the electrocardiogram are systematically performed at the patient's admission in 7, 5 and 9 establishments, respectively. However, the offer of general medical care in UHSA seems disparate and sometimes insufficient. Specialized consultations are regularly requested during hospitalizations, but no establishment benefits from a telemedicine system or specialized consultations on site. The extraction of the patient to the general hospital is therefore systematic when such a consultation is needed. But the number of penitentiary escorts per day is limited. In 6 UHSA, medical extractions are thus regularly canceled by the penitentiary administration, sometimes without a medical opinion. Finally, the patient's regular physician is only contacted in 3 UHSA during hospitalizations.

CONCLUSION

Based on these results, ways of improving the organization of general medical care in UHSA are proposed through four main axes: the structure and general organization; the general medical care; the link with the healthcare partners and the articulation with the penitentiary administration.

[Involuntary hospitalization: A survey of liberty and custody judges]

The procedure of involuntary hospitalization in France has been recently modified by the law of 5 July 2011. Since that time, a liberty and custody judge has been appointed to guarantee the rights of psychiatric inpatients and to prevent abusive hospitalizations. Currently, for one involuntary hospitalization in ten a release is decided by the liberty and custody judge although psychiatrists consider that psychiatric care is necessary. In order to improve our understanding of the role of liberty and custody judges, and how they make their decisions, we conducted a qualitative survey of liberty and custody judges in the Tribunal de Grande Instance of Lille. Three judges were questioned, based on a semi-structured interview. Judges' responses have highlighted the need for psychiatrists to strictly respect the legal procedures and to accurately describe the clinical signs and symptoms that justify the procedure of involuntary hospitalization in the medical certificates. The intervention of liberty and custody judges for patients with psychiatric disorders represents a breakthrough for patients' rights in France, reflecting that they are considered as citizens, with the same rights as others. Nonetheless, this new mission needs a progressive learning, based on mutual exchanges with doctors and caregivers.

Antidepressants Rescue Stress-Induced Disruption of Synaptic Plasticity via Serotonin Transporter-Independent Inhibition of L-Type Calcium Channels

BACKGROUND

Long-term synaptic plasticity is a basic ability of the brain to dynamically adapt to external stimuli and regulate synaptic strength and ultimately network function. It is dysregulated by behavioral stress in animal models of depression and in humans with major depressive disorder. Antidepressants have been shown to restore disrupted synaptic plasticity in both animal models and humans; however, the underlying mechanism is unclear.

METHODS

We examined modulation of synaptic plasticity by selective serotonin reuptake inhibitors (SSRIs) in hippocampal brain slices from wild-type rats and serotonin transporter (SERT) knockout mice. Recombinant voltage-gated calcium (Ca²⁺) channels in heterologous expression systems were used to determine the modulation of Ca²⁺ channels by SSRIs. We tested the behavioral effects of SSRIs in the chronic behavioral despair model of depression both in the presence and in the absence of SERT.

RESULTS

SSRIs selectively inhibited hippocampal long-term depression. The inhibition of long-term depression by SSRIs was mediated by a direct block of voltage-activated L-type Ca²⁺ channels and was independent of SERT. Furthermore, SSRIs protected both wild-type and SERT knockout mice from behavioral despair induced by chronic stress. Finally, long-term depression was facilitated in animals subjected to the behavioral despair model, which was prevented by SSRI treatment.

CONCLUSIONS

These results showed that antidepressants protected synaptic plasticity and neuronal circuitry from the effects of stress via a modulation of Ca²⁺ channels and synaptic plasticity independent of SERT. Thus, L-type Ca²⁺ channels might constitute an important signaling hub for stress response and for pathophysiology and treatment of depression.

[Involuntary psychiatric care for inmates in France: Only for "dangerous" patients?]

The unités hospitalières spécialement aménagées (UHSA) are full-time inpatient psychiatric units for inmates in France. Their creation has been associated with several advances in access to psychiatric care for inmates in recent years. However, there is still only one means of involuntary hospitalization for prisoners in France: care by decision of a representative of the state (les soins sur décision d'un représentant de l'état [SDRE]). Interestingly, for SDRE to be recognized as legal by the French judge, the patient must be "a danger to himself or to the others". Thus, there is a major difference with involuntary hospitalization outside the prison, and there are specific criteria for involuntary psychiatric hospitalization for inmates in France. This situation questions the general framework of involuntary psychiatric care and is very inconsistent with French law. Indeed, the goal of the loi n^o 94-43 du 18 janvier 1994 relating to public health and social protection is to ensure equivalent care for all patients, incarcerated or not.

Evidence for a role of eosinophils in blister formation in bullous pemphigoid

BACKGROUND

Bullous pemphigoid (BP) is an autoimmune bullous disease of the skin characterized by subepidermal blister formation due to tissue-bound and circulating autoantibodies to the hemidesmosomal antigens BP180 and BP230. Although eosinophils and their toxic mediators are found abundantly in BP lesions, their role in blister formation has remained unclear.

OBJECTIVE

To investigate the role of eosinophils in the pathogenesis of BP with a specific focus on blister formation and to define conditions inducing dermal-epidermal separation (DES).

METHODS

In an ex vivo human model of BP, normal human skin cryosections were incubated with purified human peripheral blood eosinophils with or without activation in the presence or absence of BP autoantibodies, brefeldin A, diphenyleneiodonium, DNase or blocking F(ab')₂ fragments to CD16, CD18, CD32 and CD64. Dermal-epidermal separation was assessed by light microscopy studies and quantified using Fiji software.

RESULTS

Following activation with IL-5 and in the presence of BP autoantibodies, eosinophils induced separation along the dermal-epidermal junction of ex vivo skin. Dermal-epidermal separation was significantly reduced by blocking any of the following: Fcγ receptor binding (P = 0.048), eosinophil adhesion (P = 0.046), reactive oxygen species (ROS) production (P = 0.002), degranulation (P < 0.0001) or eosinophil extracellular trap (EET) formation (P = 0.048).

CONCLUSIONS

Our results provide evidence that IL-5-activated eosinophils directly contribute to BP blister formation in the presence of BP autoantibodies. Dermal-epidermal separation by IL-5-activated eosinophils depends on adhesion and Fcγ receptor activation, requires elevated ROS production and degranulation and involves EET formation. Thus, targeting eosinophils may be a promising therapeutic approach for BP.

First Searches for Axions and Axionlike Particles with the LUX Experiment

The first searches for axions and axionlike particles with the Large Underground Xenon experiment are presented. Under the assumption of an axioelectric interaction in xenon, the coupling constant between axions and electrons g_{Ae} is tested using data collected in 2013 with an exposure totaling 95 live days ×118  kg. A double-sided, profile likelihood ratio statistic test excludes g_{Ae} larger than 3.5×10^{-12} (90% C.L.) for solar axions. Assuming the Dine-Fischler-Srednicki-Zhitnitsky theoretical description, the upper limit in coupling corresponds to an upper limit on axion mass of 0.12  eV/c^{2}, while for the Kim-Shifman-Vainshtein-Zhakharov description masses above 36.6  eV/c^{2} are excluded. For galactic axionlike particles, values of g_{Ae} larger than 4.2×10^{-13} are excluded for particle masses in the range 1-16  keV/c^{2}. These are the most stringent constraints to date for these interactions.

Limits on Spin-Dependent WIMP-Nucleon Cross Section Obtained from the Complete LUX Exposure

We present experimental constraints on the spin-dependent WIMP-nucleon elastic cross sections from the total 129.5  kg yr exposure acquired by the Large Underground Xenon experiment (LUX), operating at the Sanford Underground Research Facility in Lead, South Dakota (USA). A profile likelihood ratio analysis allows 90% C.L. upper limits to be set on the WIMP-neutron (WIMP-proton) cross section of σ_{n}=1.6×10^{-41}  cm^{2} (σ_{p}=5×10^{-40}  cm^{2}) at 35  GeV c^{-2}, almost a sixfold improvement over the previous LUX spin-dependent results. The spin-dependent WIMP-neutron limit is the most sensitive constraint to date.

Results from a Search for Dark Matter in the Complete LUX Exposure

We report constraints on spin-independent weakly interacting massive particle (WIMP)-nucleon scattering using a 3.35×10^{4}  kg day exposure of the Large Underground Xenon (LUX) experiment. A dual-phase xenon time projection chamber with 250 kg of active mass is operated at the Sanford Underground Research Facility under Lead, South Dakota (USA). With roughly fourfold improvement in sensitivity for high WIMP masses relative to our previous results, this search yields no evidence of WIMP nuclear recoils. At a WIMP mass of 50  GeV c^{-2}, WIMP-nucleon spin-independent cross sections above 2.2×10^{-46}  cm^{2} are excluded at the 90% confidence level. When combined with the previously reported LUX exposure, this exclusion strengthens to 1.1×10^{-46}  cm^{2} at 50  GeV c^{-2}.

Pre-operative Simulation of the Appropriate C-arm Position Using Computed Tomography Post-processing Software Reduces Radiation and Contrast Medium Exposure During EVAR Procedures

OBJECTIVE/BACKGROUND

The aim was to evaluate the feasibility and efficacy of a new method for pre-operative calculation of an appropriate C-arm position for iliac bifurcation visualisation during endovascular aortic repair (EVAR) procedures by using three dimensional computed tomography angiography (CTA) post-processing software.

METHODS

Post-processing software was used to simulate C-arm angulations in two dimensions (oblique, cranial/caudal) for appropriate visualisation of distal landing zones at the iliac bifurcation during EVAR. Retrospectively, 27 consecutive EVAR patients (25 men, mean ± SD age 73 ± 7 years) were identified; one group of patients (NEW; n = 12 [23 iliac bifurcations]) was compared after implementation of the new method with a group of patients who received a historic method (OLD; n = 15 [23 iliac bifurcations]), treated with EVAR before the method was applied.

RESULTS

In the OLD group, a median of 2.0 (interquartile range [IQR] 1-3) digital subtraction angiography runs were needed per iliac bifurcation versus 1.0 (IQR 1-1) runs in the NEW group (p = .007). The median dose area products per iliac bifurcation were 11951 mGy*cm² (IQR 7308-16663 mGy*cm²) for the NEW, and 39394 mGy*cm² (IQR 19066-53702 mGy*cm²) for the OLD group, respectively (p = .001). The median volume of contrast per iliac bifurcation was 13.0 mL (IQR: 13-13 mL) in the NEW and 26 mL (IQR 13-39 mL) in the OLD group (p = .007).

CONCLUSION

Pre-operative simulation of the appropriate C-arm angulation in two dimensions using dedicated computed tomography angiography post-processing software is feasible and significantly reduces radiation and contrast medium exposure.

Hymenoptera stings in the head region induce impressive, but not severe sting reactions

Stings in the head region are considered to be a risk factor for severe systemic reactions to hymenoptera stings. We supposed that stings in skin areas, which are well supplied with blood, lead to more severe reactions and tested our hypothesis in 847 patients with confirmed hymenoptera venom allergy. However, symptom severity was independent from sting site: only 16.3% of patients with severe reactions were stung on the head (P = 0.017). But we confirmed age > 40 years (P < 0.001) as well as elevated basal tryptase levels (P = 0.001) as risk factors. Taking antihypertensive drugs seemed to have an influence: 41.7% of patients taking antihypertensive drugs experienced a severe reaction compared to 29.5% of patients, not taking such drugs (P = 0.019). However, considering patients' age in regression analysis, taking antihypertensive drugs had no effect on symptom severity (P = 0.342). Importantly, in most patients with severe reactions, cutaneous signs were absent (P < 0.001).

Myocardial lipid content in Fabry disease: a combined 1H-MR spectroscopy and MR imaging study at 3 Tesla

BACKGROUND

Fabry disease is characterized by a progressive deposition of sphingolipids in different organ systems, whereby cardiac involvement leads to death. We hypothesize that lysosomal storage of sphingolipids in the heart as occurring in Fabry disease does not reflect in higher cardiac lipid concentrations detectable by ¹H magnetic resonance spectroscopy (MRS) at 3 Tesla.

METHODS

Myocardial lipid content was quantified in vivo by ¹H-MRS in 30 patients (12 male, 18 female; 18 patients treated with enzyme replacement therapy) with genetically proven Fabry disease and in 30 healthy controls. The study protocol combined ¹H-MRS with cardiac cine imaging and LGE MRI in a single examination.

RESULTS

Myocardial lipid content was not significantly elevated in Fabry disease (p = 0.225). Left ventricular (LV) mass was significantly higher in patients suffering from Fabry disease compared to controls (p = 0.019). Comparison of patients without signs of myocardial fibrosis in MRI (LGE negative; n = 12) to patients with signs of fibrosis (LGE positive; n = 18) revealed similar myocardial lipid content in both groups (p > 0.05), while the latter showed a trend towards elevated LV mass (p = 0.076).

CONCLUSIONS

This study demonstrates the potential of lipid metabolic investigation embedded in a comprehensive examination of cardiac morphology and function in Fabry disease. There was no evidence that lysosomal storage of sphingolipids influences cardiac lipid content as measured by ¹H-MRS. Finally, the authors share the opinion that a comprehensive cardiac examination including three subsections (LGE; ¹H-MRS; T₁ mapping), could hold the highest potential for the final assessment of early and late myocardial changes in Fabry disease.

TRADITIONAL CANISTER-BASED OPEN WASTE MANAGEMENT SYSTEM VERSUS CLOSED SYSTEM: HAZARDOUS EXPOSURE PREVENTION AND OPERATING THEATRE STAFF SATISFACTION

INTRODUCTION

Exposure to blood and body fluids is a major concern to health care professionals working in operating rooms (ORs). Thus, it is essential that hospitals use fluid waste management systems that minimise risk to staff, while maximising efficiency.

METHOD

The current study compared the utility of a 'closed' system with a traditional canister-based 'open' system in the OR in a private hospital setting.

RESULTS

A total of 30 arthroscopy, urology, and orthopaedic cases were observed. The closed system was used in five, four, and six cases, respectively and the open system was used in nine, two, and four cases, respectively. The average number of opportunities for staff to be exposed to hazardous fluids were fewer for the closed system when compared to the open during arthroscopy and urology procedures. The open system required nearly 3.5 times as much staff time for set-up, maintenance during procedures, and post-procedure disposal of waste. Theatre staff expressed greater satisfaction with the closed system than with the open.

CONCLUSION

In conclusion, compared with the open system, the closed system offers a less hazardous and more efficient method of disposing of fluid waste generated in the OR.

Results on the Spin-Dependent Scattering of Weakly Interacting Massive Particles on Nucleons from the Run 3 Data of the LUX Experiment

We present experimental constraints on the spin-dependent WIMP (weakly interacting massive particle)-nucleon elastic cross sections from LUX data acquired in 2013. LUX is a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota), which is designed to observe the recoil signature of galactic WIMPs scattering from xenon nuclei. A profile likelihood ratio analysis of 1.4×10^{4}  kg day of fiducial exposure allows 90% C.L. upper limits to be set on the WIMP-neutron (WIMP-proton) cross section of σ_{n}=9.4×10^{-41}  cm^{2} (σ_{p}=2.9×10^{-39}  cm^{2}) at 33  GeV/c^{2}. The spin-dependent WIMP-neutron limit is the most sensitive constraint to date.

Improved Limits on Scattering of Weakly Interacting Massive Particles from Reanalysis of 2013 LUX Data

We present constraints on weakly interacting massive particles (WIMP)-nucleus scattering from the 2013 data of the Large Underground Xenon dark matter experiment, including 1.4×10^{4}  kg day of search exposure. This new analysis incorporates several advances: single-photon calibration at the scintillation wavelength, improved event-reconstruction algorithms, a revised background model including events originating on the detector walls in an enlarged fiducial volume, and new calibrations from decays of an injected tritium β source and from kinematically constrained nuclear recoils down to 1.1 keV. Sensitivity, especially to low-mass WIMPs, is enhanced compared to our previous results which modeled the signal only above a 3 keV minimum energy. Under standard dark matter halo assumptions and in the mass range above 4  GeV c^{-2}, these new results give the most stringent direct limits on the spin-independent WIMP-nucleon cross section. The 90% C.L. upper limit has a minimum of 0.6 zb at 33  GeV c^{-2} WIMP mass.

Tuning the properties of a novel short cell-penetrating peptide by intramolecular cyclization with a triazole bridge

Cyclic versus linear: cyclic triazole-bridged cell-penetrating peptides are optimally arranged within the membrane, thus at the same time inducing suitable DNA complexation and successful peptide membrane insertion.

Schizophrénie et violence : données actuelles et controverse

L’association entre schizophrénie et violence a longtemps été controversée, mais les données issues des études les plus récentes établissent un lien clair entre schizophrénie et risque de violence. Néanmoins, tous les patients schizophrènes ne présentent pas un risque égal de passage à l’acte violent. Différents facteurs de risque ont ainsi pu être identifiés, tels l’intensité de la symptomatologie psychotique, l’impulsivité ou les comorbidités addictives. Récemment, différents auteurs ont émis l’hypothèse de différents sous-groupes de patients schizophrènes à risque de comportements violents : la majorité des actes commis par les patients schizophrènes représenteraient des gestes de violence mineure alors que les actes de violence majeure ne seraient commis que par une faible proportion de ces patients. Pour l’ensemble de ces patients, des difficultés persistent dans l’établissement de leur responsabilité pénale. Le code pénal français prévoit l’irresponsabilité pénale pour les personnes atteintes, au moment des faits, d’un trouble psychique ou neuropsychique ayant aboli leur discernement ou le contrôle de leurs actes. Pour autant, la reconnaissance de la responsabilité pénale des personnes atteintes de troubles mentaux semble en augmentation, augmentant ainsi le nombre de patients schizophrènes en détention. Une première partie aura pour objectif d’approfondir l’étude des facteurs de risque des comportements violents, en intégrant l’hétérogénéité des gestes de violence, à partir d’une étude descriptive de patients schizophrènes incarcérés. Une attention particulière sera portée sur les liens existant entre troubles de la familiarité et passages à l’acte violents. Une deuxième partie s’intéressera aux facteurs neurobiologiques des comportements violents des patients schizophrènes, grâce à l’étude du lien entre impulsivité et violence en imagerie par résonance magnétique fonctionnelle (IRMf). Enfin, une troisième partie abordera la question de la responsabilité de ces patients souffrant de troubles mentaux et présentant des comportements violents, et s’intéressera notamment aux nouvelles techniques d’approches expertales de la responsabilité.