The dehydration mechanism of Na and K birnessites: a comprehensive multitechnique study.

The structural, spectroscopic and electronic properties of Na and K birnessites were investigated from ambient conditions (birA) to complete dehydration, and the involved mechanisms were scrutinized. Density Functional Theory (DFT) simulations were employed to derive structural models for lamellar A0.33MnO2·xH2O (A = Na+ or K+, x = 0 or 0.66), subsequently compared with the experimental results obtained for Na0.30MnO2·0.75H2O and K0.22MnO2·0.77H2O materials. Thermal analysis (TGA-DSC), X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, and Near Ambient Pressure X-ray Photoemission Spectroscopy (NAP-XPS) measurements were conducted for both birnessites. Dehydration under vacuum, annealing, or controlled relative humidity were considered. Results indicated that complete birnessite dehydration was a two-stage process. In the first stage, water removal from the interlayer of fully hydrated birnessite (birA) down to a molar H2O/A ratio of ∼2 (birB) led to the progressive shrinkage of the interlayer distance (3% for Na birnessite, 1% for K birnessite). In the second stage, water-free (birC) domains with a shorter interlayer distance (20% for Na birnessite, 10% for K birnessite) appeared and coexisted with birB domains. Then, birB was essentially transformed into birC when complete dehydration was achieved. The vibrational properties of birA were consistent with strong intermolecular interactions among water molecules, whereas partially dehydrated birnessite (birB) showed a distinct feature, with 3 (for Na-bir) and 2 (for K-bir) vibrations that were reproduced by DFT calculations for organized water into the interlayer (x = 0.66). The study also demonstrated that the electronic structure of Na birnessite depends on the interlayer water content. The external Na+ electronic level (Na 2p) was slightly destabilized (+0.3 eV binding energy) under near ambient conditions (birA) compared to drier conditions (birB and birC).

Role of fluid status markers as risk factors for suboptimal vancomycin concentration during continuous infusion in neonates: an observational study.

Vancomycin is widely used in neonatal sepsis but proportion of newborn reaching recommended concentration is variable. Fluid status impact on vancomycin level remains understudied. We aimed to study fluid factors impacting vancomycin concentration at 24 h of treatment. We performed a prospective and retrospective observational monocentric study of NICU patients requiring a vancomycin treatment. We used a continuous infusion protocol, with age-appropriate loading and maintenance doses. Vancomycin target serum concentration after 24 h (C24h) was above 20 mg/L. Demographic, infections, and organ failure variables were analyzed as potential predictors of C24h. Over the study period, 70 infective episodes in 52 patients were included. At treatment initiation, the median post-natal age was 12.5 days (IQR 7-23), post menstrual age 30 weeks (IQR 28-35), and median weight 1140 g (IQR 835-1722). Germs isolated were mainly gram-positive with 73.5% being coagulase-negative Staphylococci. Median C24h was 18.7 mg/L (IQR 15.4-22.4). Overall, 41 (58.6%) treatments had a C24h < 20 mg/L. After multivariate analysis, higher creatinine level (OR 1.03 (95% CI 1.002-1.06)) was associated with C24h ≥ 20 mg/L; weight gain the day before infection (OR 0.21 (95% CI 0.05-0.79)) and positive biomarkers of inflammation (OR 0.22 (0.05-0.94)) were associated with C24h < 20 mg/L. CONCLUSION: Vancomycin C24h was underdosed in 60% of patients and factors linked to changes in vancomycin pharmacokinetic such as volume of distribution and clearance, linked to creatinine level, inflammation, or weight gain, were identified. WHAT IS KNOWN: • Adjustment of vancomycin regimen remains difficult due to inter- and intra-individual variability of vancomycin pharmacokinetics. • Impact of fluid status on vancomycin concentration in critically ill neonates is incompletely studied. WHAT IS NEW: • Proportion of patients with adequate vancomycin concentration using a target adapted to nosocomial gram-positive bacteria MIC is low. • We confirmed the role of creatinine level and report two new factors associated with low vancomycin concentration: presence of systemic inflammation and weight gain.

Abdominal musculature segmentation and surface prediction from CT using deep learning for sarcopenia assessment.

PURPOSE: The purpose of this study was to build and train a deep convolutional neural networks (CNN) algorithm to segment muscular body mass (MBM) to predict muscular surface from a two-dimensional axial computed tomography (CT) slice through L3 vertebra. MATERIALS AND METHODS: An ensemble of 15 deep learning models with a two-dimensional U-net architecture with a 4-level depth and 18 initial filters were trained to segment MBM. The muscular surface values were computed from the predicted masks and corrected with the algorithm's estimated bias. Resulting mask prediction and surface prediction were assessed using Dice similarity coefficient (DSC) and root mean squared error (RMSE) scores respectively using ground truth masks as standards of reference. RESULTS: A total of 1025 individual CT slices were used for training and validation and 500 additional axial CT slices were used for testing. The obtained mean DSC and RMSE on the test set were 0.97 and 3.7 cm2 respectively. CONCLUSION: Deep learning methods using convolutional neural networks algorithm enable a robust and automated extraction of CT derived MBM for sarcopenia assessment, which could be implemented in a clinical workflow.

[Glassy cell carcinoma of the uterine cervix: An aggressive type of cancer]. / Glassy cell carcinoma du col de l'utérus : une maladie tumorale agressive.

INTRODUCTION: Cervical cancer is the twelfth most frequent cancer in women in France. Glassy cell carcinoma is a rare histological entity, rapidly aggressive, associated with a poor prognosis. CASE REPORT: A 30-year-old woman was admitted in an internal medicine department for polyarthralgia with high grade fever, evolving for 3 weeks. There was an inflammatory syndrome. The 18-FDG-PET-scan showed inflammatory lymph nodes as well as disseminated osteolytic lesions, and a primitive pelvic tumor. A 3cm tumor of the cervix was found during the gynaecologic examination. Histological analysis elicited a high-index mitotic carcinoma, glassy cell carcinoma type. Despite chemotherapy, the outcome was poor, with early death occurring after three months of follow-up. CONCLUSION: The glassy cell carcinoma of the cervix should be considered as an aetiology of bone metastases in young female patients.

[Can a simple lung ultrasound score predict length of ventilation for infants with severe acute viral bronchiolitis?] / Un score échographique pulmonaire simple peut-il prédire la durée de ventilation des nourrissons atteints de bronchiolite aiguë sévère ?

BACKGROUND: Lung ultrasound (LU) is a bedside point-of-care technique in critical care and emergency medicine. LU is quick and non-irradiating, and provides accurate diagnostic information when compared with chest radiographs. Specific LU signs have been described for bronchiolitis. This study aimed to evaluate the correlation between severity of LU-diagnosed lung lesions, using a quantitative LU score, and the length of non-invasive ventilation (LOV) for infants diagnosed with severe viral bronchiolitis. METHODS: This was a prospective observational single-center study conducted at a level 3 pediatric intensive care unit. A LU score was calculated for 47 infants under 6 months of age with severe acute viral bronchiolitis during the 2015-2016 epidemic, and the number of intercostal spaces with consolidation or interstitial syndrome was counted for each lung. The LU score is based on the presence of A lines or B-line artifacts and consolidation (0-2 points). The modified Wood score (mWCAS) was used to define clinical severity. Other parameters such as gestational age at birth, age, supplemental oxygen (LOS), and length of stay were recorded. All LU scans were later reviewed by two trained ultrasonographers to assess the score's inter-rater reproducibility. RESULTS: The LU score on admission (3.5±2.6) did not correlate with LOV (69±68.6), mWCAS score (4±1.6), LOS (3±3.4), or length of stay (4±3.4). However, there was a significant correlation between the number of affected intercostal spaces on the right and LOS (Spearman's Rho 0.318; P=0.037). CONCLUSION: This is the first study to evaluate the use of LU in infants needing PICU admission for severe acute bronchiolitis. The LU score does not correlate with LOV, mWCAS, LOS, or length of stay, but the number of pathological intercostal spaces on the right side correlates significantly with LOS. Although LU scores have been validated for the newborn and the adult, this has been in the setting of restrictive lung diseases. Bronchiolitis is a predominantly obstructive lung disease and this may explain the lack of performance observed.

Quality improvement program of adult urinary tract infection management: Review and impact.

OBJECTIVE: A quality improvement program for adult urinary tract infection management was established to avoid unnecessary antibiotic treatment and to promote adequate prescription, associated with financial and time savings. METHODS: Management was integrated into a three-step approach: clinical diagnosis, bacteriological diagnosis, and therapeutic decision. For each step, areas for improvement were prioritized and implemented through corrective measures and key messages, measured by indicators. This program was applied to the whole hospital, which includes an emergency department and hospital units (672 beds). RESULTS: The diffusion of new recommendations on clinical diagnosis helped limit the use of Urine Dipstick Tests (UDT) and identify situations requiring the prescription of urine cytobacteriological test (UCBE) and antibiotic treatment: decreased annual consumption of UDTs (34%) and UCBEs (25%). The implementation of a new sampling system for UCBEs was associated with a 21% increase in conclusive analysis. Results of antimicrobial susceptibility testing were also optimized. Trainings on the proper use of antibiotics led to a 5.0% decline in global consumption. Only 23 antibiotic prescriptions for UTI resulted in pharmaceutical advice to prescribers in 2014. CONCLUSION: The program is part of a practice improvement strategy. Integrating the management of urinary tract infections into a global process helped improve each step of patient management.

The First 2 Years of Activity of a Specialized Organ Procurement Center: Report of an Innovative Approach to Improve Organ Donation.

The number of patients requiring organ transplants continues to outgrow the number of organs donated each year. In an attempt to improve the organ donation process and increase the number of organs available, we created a specialized multidisciplinary team within a specialized organ procurement center (OPC) with dedicated intensive care unit (ICU) beds and operating rooms. The OPC was staffed with ICU nurses, operating room nurses, organ donor management ICU physicians, and multidisciplinary staff. All organ donors within a designated geographic area were transferred to and managed within the OPC. During the first 2 years of operation, 126 patients were referred to the OPC. The OPC was in use for a total of 3527 h and involved 253 health workers. We retrieved 173 kidneys, 95 lungs, 68 livers, 37 hearts, and 13 pancreases for a total of 386 organs offered for transplantation. This translates to a total of 124.6 persons transplanted per million population, which compares most favorably to recently published numbers in developed countries. The OPC clearly demonstrates potential to increase the number of deceased donor organs available for transplant. Further studies are warranted to better understand the exact influence of the different components of the OPC on organ procurement.

Characterization and phylogenetic analysis of new bat astroviruses detected in Gabon, Central Africa.

Astroviruses are emerging RNA viruses that cause enteropathogenic infections in humans and in other mammals. The identification of astroviruses in a wide range of animals highlights the zoonotic importance of these viruses. Bats can harbor many different viruses, among which some are highly pathogenic for humans (for instance, Nipah, Ebola and SARS coronavirus), and also several astroviruses. As some RNA viruses can be directly transmitted from bats to humans, it is crucial to collect data about their frequency, genetic diversity and phylogenetic characterization. In this study, we report the molecular identification of 44 new astroviruses (with a detection rate of 4.5%) in 962 apparently healthy bats that belong to five different species and that were captured in different caves in North-East Gabon, Central Africa. Our results show that bat astroviruses form a group that is genetically distinct from astroviruses infecting other mammals. Moreover, these astroviruses showed an important genetic diversity and low host restriction in bat species.

Cerebral venous thrombosis after embolization of pediatric AVM with jugular bulb stenosis or occlusion: management and prevention.

PURPOSE: Thrombosis of cerebral arteriovenous malformation after embolization is rare, but can involve the normal venous network with extensive venous thrombosis. We report angioarchitecture findings, our management and prevention strategy for this complication in pediatric AVMs. METHODS: In this 5.5-year retrospective series, we reviewed records of 13 patients under 15 years who were anticoagulated after embolization. In our initial experience 4 children who didn't receive any prophylactic anticoagulation presented with extensive venous thrombosis after embolization (group 1). Following this, nine children with similar angioarchitecture and embolization modalities were treated with prophylactic anticoagulation immediately after embolization (group 2). We analyzed the type of AVM, angioarchitecture, dose of prophylactic anticoagulant, efficacy/complications of treatment and late outcome. RESULTS: All patients in group 1 had severe jugular bulb stenosis/occlusion associated with cerebral venous dilatation. In group 2 with similar angioarchitecture, only three patients (33%) developed extensive thrombosis. In both groups, thrombosis occurred within two days of treatment in six children and two weeks in one child. The diagnosis was suspected on intracranial hypertension in five patients and occulomotor disorder in one. One was asymptomatic. All children were treated with therapeutic doses of LMWH (anti-Xa: 0.5-1). No hemorrhagic complications occurred. Good venous remodeling was observed in all but one patient. CONCLUSION: Anticoagulation in extensive venous thrombosis after AVM embolization in children appears to be safe and effective. In cases with angioarchitectural features of dilatation of the cerebral venous network and occlusion/severe stenosis of the jugular bulbs, full dose anticoagulation may be required to prevent thrombosis.

Amazonian palm Oenocarpus bataua ("patawa"): chemical and biological antioxidant activity--phytochemical composition.

In French Guiana, "diversity" within the Palm family is obvious since more than 75 species have been identified. Oenocarpus bataua Mart., called "patawa" is well known for its culinary uses whereas literature on its phytochemical composition and biological properties remains poor. This work deals with determining the antioxidant activity of this palm fruit and its polyphenol composition; Euterpe oleracea (açai) used as a reference. It turned out that patawa had a stronger antioxidant activity than açai in TEAC and FRAP tests. A similar activity was observed by DPPH assay whereas in ORAC and KRL tests, that açai showed an antioxidant activity respectively 2.6 and 1.5 fold higher than patawa. Polyphenolic composition, determined by UPLC/MS(n), would imply the presence of anthocyanins, condensed tannins, stilbenes and phenolic acids, well known for their biological activities. These results present patawa fruit as a new amazonian resource for cosmetics, food and pharmaceuticals purposes.

A benign psoas teratoma of the non-pelvic retroperitoneal space: A case report.

This case report is of a benign retroperitoneal teratoma which was adherent to the psoas muscle of a 53-year-old female cadaver with a history of metastatic bladder cancer as a cause of death. Teratomas possess derivatives of all three germ cell layers and are usually seen either in children or in the lower pelvic region of adults. The finding of this mass deep to the inferior pole of the kidney is quite unusual. Few studies mention a possible association between metastatic cancer and teratoma growth in extrapelvic locations. The following report is a detailed account of this unusual finding and a summary of the literature on growths of this kind.

[Medical care of brain malformative vascular diseases discovered during the pre- or neonatal period]. / Prise en charge des malformations vasculaires cérébrales découvertes en période ante- ou néonatale.

Three types of brain arteriovenous vascular malformations can be found during the neonatal period, according to their anatomical location. Vein of Galen malformations are the most common. The others are pial arteriovenous malformations or dural arteriovenous malformations, which include dural sinus malformations. They can be asymptomatic, but most often they are associated with different symptoms, related to their angioarchitecture or their effect on the brain. High-flow arteriovenous malformations can thus be responsible for heart failure. Local or regional venous hyperpressure exposes the patient to subacute or chronic brain lesions, or to hydrovenous disorders such as hydrocephalus. Some types of venous reflux can expose patients to brain hemorrhage. The treatment chosen for these vascular malformations and their consequences is transarterial or transvenous embolization, depending on the angioarchitecture and type of lesion. The schedule for the treatment will be determined according to the malformation type and its local or general effects on the brain. The aim of this article is to present the recommendations of the French National Referral Center for neurovascular malformations in children, in order to help clinicians and radiologists treat these patients during pre- or neonatal period.

Modeling the potential benefits of catch-crop introduction in fodder crop rotations in a Western Europe landscape.

Among possible mitigation options to reduce agricultural-borne nitrate fluxes to water bodies, introduction of catch crop before spring crops is acknowledged as a cost-efficient solution at the plot scale, but it was rarely assessed at the catchment level. This study aims to evaluate a set of catch crop implantation scenarios and their consequences in a coastal catchment prone to eutrophication. The objectives are (i) to discuss the potential benefits of catch crop introduction taking into account the limitations due to the physiographic and agricultural context of the area (ii) to propose a multicriteria classification of these scenarios as a basis for discussion with stakeholders. We used the distributed agro-hydrological model TNT2 to simulate 25 scenarios of catch crop management, differing in length of catch crop growing period, place in the crop rotation and residue management. The scenarios were classified considering the variations in main crop yields and either nitrogen fluxes in stream or the global nitrogen mass balance at the catchment level. The simulations showed that in the catchment studied, little improvement can be expected from increasing the catch crop surface. Catch crop cultivation was always beneficial to reduce nitrogen losses, but led to adverse effects on main crop yields in some cases. Among the scenarios involving additional catch crop surface, introducing catch crop between two winter cereals appeared as the most promising. The classification of scenarios depended on the chosen criteria: when considering only the reduction of nitrogen fluxes in streams, exporting catch crop residues was the most efficient while when considering the global nitrogen mass balance, soil incorporation of catch crop residues was the most beneficial. This work highlights the interest, while using integrated models, of assessing simulated scenarios with multicriteria approach to provide stakeholder with a picture as complete as possible of the consequences of prospective policies.

An African horse sickness virus serotype 4 recombinant canarypox virus vaccine elicits specific cell-mediated immune responses in horses.

A recombinant canarypox virus vectored vaccine co-expressing synthetic genes encoding outer capsid proteins, VP2 and VP5, of African horse sickness virus (AHSV) serotype 4 (ALVAC(®)-AHSV4) has been demonstrated to fully protect horses against homologous challenge with virulent field virus. Guthrie et al. (2009) detected weak and variable titres of neutralizing antibody (ranging from <10 to 40) 8 weeks after vaccination leading us to hypothesize that there could be a participation of cell mediated immunity (CMI) in protection against AHSV4. The present study aimed at characterizing the CMI induced by the experimental ALVAC(®)-AHSV4 vaccine. Six horses received two vaccinations twenty-eight days apart and three horses remained unvaccinated. The detection of VP2/VP5 specific IFN-γ responses was assessed by enzyme linked immune spot (ELISpot) assay and clearly demonstrated that all ALVAC(®)-AHSV4 vaccinated horses developed significant IFN-γ production compared to unvaccinated horses. More detailed immune responses obtained by flow cytometry demonstrated that ALVAC(®)-AHSV4 vaccinations induced immune cells, mainly CD8(+) T cells, able to recognize multiple T-epitopes through all VP2 and only the N-terminus sequence of VP5. Neither VP2 nor VP5 specific IFN-γ responses were detected in unvaccinated horses. Overall, our data demonstrated that an experimental recombinant canarypox based vaccine induced significant CMI specific for both VP2 and VP5 proteins of AHSV4.

NitroScape: a model to integrate nitrogen transfers and transformations in rural landscapes.

Modelling nitrogen transfer and transformation at the landscape scale is relevant to estimate the mobility of the reactive forms of nitrogen (N(r)) and the associated threats to the environment. Here we describe the development of a spatially and temporally explicit model to integrate N(r) transfer and transformation at the landscape scale. The model couples four existing models, to simulate atmospheric, farm, agro-ecosystem and hydrological N(r) fluxes and transformations within a landscape. Simulations were carried out on a theoretical landscape consisting of pig-crop farms interspersed with unmanaged ecosystems. Simulation results illustrated the effect of spatial interactions between landscape elements on N(r) fluxes and losses to the environment. More than 10% of the total N(2)O emissions were due to indirect emissions. The nitrogen budgets and transformations of the unmanaged ecosystems varied considerably, depending on their location within the landscape. The model represents a new tool for assessing the effect of changes in landscape structure on N(r) fluxes.

[Necrotizing community-acquired Staphylococcus aureus pneumonia]. / Pneumopathie aiguë nécrosante à Staphylocoque doré sécréteur de la toxine de Panton-Valentine.

Acute necrotizing pneumonia due to Panton-Valentine secreting Staphylococcus aureus was identified as a clinical entity by Gilet et al., in 2002. This severe acute necrotizing pneumonia occurring in previously healthy children and adolescents can lead to a rapid fatal outcome even if quickly diagnosed and treated. We report the case of a healthy 10-year-old girl presenting with hemorrhagic necrotizing pneumonia and septic shock. Bacteriological cultures yielded methicillin-susceptible Staphylococcus aureus. The course of the disease was characterized by recurrent uncontrolled hemoptysia leading to refractory hypoxemia. The details of the hospital stay are presented. We discuss the clinical features of the disease and describe recent epidemiologic data and Panton-Valentine toxin research results as well as primary hospital care and treatment.