Is a Positive Prehospital FAST Associated with Severe Bleeding? A Multicenter Retrospective Study.

INTRODUCTION: Severe hemorrhage is the leading cause of early preventable death in severe trauma patients. Delayed diagnosis is a poor prognostic factor, and severe hemorrhage prediction is essential. The aim of our study was to investigate if there was an association between the detection of peritoneal or pleural fluid on prehospital sonography for trauma and posttraumatic severe hemorrhage. METHODS: We retrospectively studied data from records of thoracic or abdominal trauma patients managed in mobile intensive care units from January 2017 to December 2021 in four centers in France. Severe hemorrhage was defined as a condition necessitating transfusion of at least four packed red blood cells or surgical intervention/radioembolization for hemostasis within the first 24 h. Using a multivariate analysis, we investigated the predictive performance of focused assessment with sonography for trauma (FAST) alone or in combination with the five Red Flags criteria validated by Hamada et al. RESULTS: Among the 527 patients analyzed, 371 (71%) were men, the mean age was 41 ± 19 years, and the Injury Severity Score was 11 (Interquartile range = [5; 22]). Seventy-three (14%) patients had severe hemorrhage - of whom 28 (38%) had a positive FAST, compared to 61 (13%) without severe hemorrhage (p < 0.01). For severe hemorrhage prediction, FAST had a sensitivity of 38% (95%CI = [27%; 50%]) and a specificity of 87% (95%CI = [83%; 90%]) (AUC = 0.62, 95%CI = [0.57; 0.68]). The comparison of the other outcomes between positive and negative FAST was: hemostatic procedure, 22 (25%) vs 28 (6%), p < 0.01; intensive care unit admission 71 (80%) vs 190 (43%), p < 0.01; mean length of hospital stay 11 [4; 27] vs 4 [0; 14] days, p = 0.02; 30-day mortality 13 (15%) vs 22 (5%), p < 0.01. CONCLUSION: A positive FAST performed in the prehospital setting is associated with severe hemorrhage and all prognostic criteria we studied.

Huge discrepancy between serum immunoglobulin concentration and proteinemia due to heavy chain disease.

Immunoassays are widely used in clinical laboratories because of their ease of use and low cost. These tests are based on antigen-antibody binding. However, clinicians and laboratory personnel may be confronted with immunoassay interference leading to difficulties in medical care. Here, we report a huge analytical discrepancy with IgG concentration higher than proteinemia in a 75-year-old man. Serum electrophoresis and immunofixation diagnosed γ-heavy chain disease. After investigation by different methods, the assay discrepancy was still present. We hypothesize that the interference is related to the truncated immunoglobulin secreted by the lymphoproliferative disorder.

Insight into the Nature of the ZnO x Promoter during Methanol Synthesis.

Despite the great commercial relevance of zinc-promoted copper catalysts for methanol synthesis, the nature of the Cu-ZnO x synergy and the nature of the active Zn-based promoter species under industrially relevant conditions are still a topic of vivid debate. Detailed characterization of the chemical speciation of any promoter under high-pressure working conditions is challenging but specifically hampered by the large fraction of Zn spectator species bound to the oxidic catalyst support. We present the use of weakly interacting graphitic carbon supports as a tool to study the active speciation of the Zn promoter phase that is in close contact with the Cu nanoparticles using time-resolved X-ray absorption spectroscopy under working conditions. Without an oxidic support, much fewer Zn species need to be added for maximum catalyst activity. A 5-15 min exposure to 1 bar H2 at 543 K only slightly reduces the Zn(II), but exposure for several hours to 20 bar H2/CO and/or H2/CO/CO2 leads to an average Zn oxidation number of +(0.5-0.6), only slightly increasing to +0.8 in a 20 bar H2/CO2 feed. This means that most of the added Zn is in a zerovalent oxidation state during methanol synthesis conditions. The Zn average coordination number is 8, showing that this phase is not at the surface but surrounded by other metal atoms (whether Zn or Cu), and indicating that the Zn diffuses into the Cu nanoparticles under reaction conditions. The time scale of this process corresponds to that of the generally observed activation period for these catalysts. These results reveal the speciation of the relevant Zn promoter species under methanol synthesis conditions and, more generally, present the use of weakly interacting graphitic supports as an important strategy to avoid excessive spectator species, thereby allowing us to study the nature of relevant promoter species.

Dorsal root ganglion stimulation for refractory post-herpetic neuralgia.

Post-herpetic neuralgia is a chronic neuropathic pain disorder that is the sequela of the varicella zoster virus reactivation in the dorsal root ganglion. A variety of treatment modalities have been implemented, but pharmacologic treatments are often limited due to side effects and interventional procedures have yielded mixed results without promising long-term benefits being consistently seen. A dorsal root ganglion stimulator for treatment of post-herpetic neuralgia is a novel treatment option as it is able to specifically target the area affected. We present 3 patients who underwent implantation of permanent dorsal root ganglion stimulators and had a greater than 50% decrease in scoring on numerical rating scale (NRS) up to 18 months post-procedure and significantly reduced analgesic requirements.

Insight into the thermal decomposition of ammonium hexahalogenoiridates(IV) and hexachloroiridate(III).

Thermal decomposition of (NH4)3[IrCl6]·H2O, (NH4)2[IrCl6] and (NH4)2[IrBr6] in reductive and inert atmospheres has been investigated in situ using quick-EXAFS and temperature-resolved powder X-ray diffraction. For the first time, (NH4)2[Ir(NH3)Cl5] and (NH4)2[Ir(NH3)Br5] have been proven as intermediates of thermal decomposition of (NH4)3[IrCl6]·H2O, (NH4)2[IrCl6] and (NH4)2[IrBr6]. Thermal degradation of (NH4)2[IrCl6] and (NH4)2[IrBr6] is a more complex process as suggested previously and includes simultaneous formation of (NH4)2[Ir(NH3)Cl5] and (NH4)2[Ir(NH3)Br5] intermediates mixed with metallic iridium. In the inert atmosphere, complexes (NH4)[Ir(NH3)2Cl4] and (NH4)[Ir(NH3)2Br4] as well as [Ir(NH3)3Br3] were proposed as possible intermediates before formation of metallic iridium particles.

Multivariate Analysis of Coupled Operando EPR/XANES/EXAFS/UV-Vis/ATR-IR Spectroscopy: A New Dimension for Mechanistic Studies of Catalytic Gas-Liquid Phase Reactions.

Operando EPR, XANES/EXAFS, UV-Vis and ATR-IR spectroscopic methods have been coupled for the first time in the same experimental setup for investigation of unclear mechanistic aspects of selective aerobic oxidation of benzyl alcohol by a Cu/TEMPO catalytic system (TEMPO=2,2,6,6-tetramethylpiperidinyloxyl). By multivariate curve resolution with alternating least-squares fitting (MCR-ALS) of simultaneously recorded XAS and UV-Vis data sets, it was found that an initially formed (bpy)(NMI)CuI - complex (bpy=2,2'-bipyridine, NMI=N-methylimidazole ) is converted to two different CuII species, a mononuclear (bpy)(NMI)(CH3 CN)CuII -OOH species detectable by EPR and ESI-MS, and an EPR-silent dinuclear (CH3 CN)(bpy)(NMI)CuII (µ-OH)2 ⋅CuII (bpy)(NMI) complex. The latter is cleaved in the further course of reaction into (bpy)(NMI)(HOO)CuII -TEMPO monomers that are also EPR-silent due to dipolar interaction with bound TEMPO. Both Cu monomers and the Cu dimer are catalytically active in the initial phase of the reaction, yet the dimer is definitely not a major active species nor a resting state since it is irreversibly cleaved in the course of the reaction while catalytic activity is maintained. Gradual formation of non-reducible CuII leads to slight deactivation at extended reaction times.

Quick-EXAFS and Raman monitoring of activation, reaction and deactivation of NiCu catalysts obtained from hydrotalcite-like precursors.

The understanding of phase transformation upon activation, reaction and deactivation of catalysts is of prime importance for tailoring catalysts with better performances. Herein we combined Quick-EXAFS and Raman spectroscopies in operando conditions through the monitoring of reaction products by mass spectrometry in order to study in depth active species and deactivating ones for Ethanol Steam Reforming reaction. Quick-EXAFS data analyzed by multivariate analysis allows one to determine the nickel and copper species involved during the activation of a Ni-Cu hydrotalcite-like precursors. Upon reaction and regeneration monitoring, Raman spectroscopy combined with mass spectrometry highlights the side products formed upon ESR leading to the formation of amorphous coke species encapsulating active metallic species and inducing catalyst deactivation. The coke encapsulation of active species was demonstrated by the simultaneous observation of oxidation of nickel and copper as soon as the amorphous coke was burnt by the oxidative regeneration treatment. Formation of filamentous coke species is also confirmed as causing little impact in catalyst deactivation.

In Situ Observation of Atomic Redistribution in Alloying Gold-Silver Nanorods.

The catalytic performance and optical properties of bimetallic nanoparticles critically depend on the atomic distribution of the two metals in the nanoparticles. However, at elevated temperatures, during light-induced heating, or during catalysis, atomic redistribution can occur. Measuring such metal redistribution in situ is challenging, and a single experimental technique does not suffice. Furthermore, the availability of a well-defined nanoparticle system has been an obstacle for a systematic investigation of the key factors governing the atomic redistribution. In this study, we follow metal redistribution in precisely tunable, single-crystalline Au-core, Ag-shell nanorods in situ, both at a single particle and an ensemble-averaged level, by combining in situ transmission electron spectroscopy with in situ extended X-ray absorption fine structure validated by ex situ measurements. We show that the kinetics of atomic redistribution in Au-Ag nanoparticles depend on the metal composition and particle volume, such that a higher Ag content or a larger particle size led to significantly slower metal redistribution. We developed a simple theoretical model based on Fick's first law that can correctly predict the composition- and size-dependent alloying behavior in Au-Ag nanoparticles, as observed experimentally.

The Day-Hospital of the University Hospital, Bobo Dioulasso: An Example of Optimized HIV Management in Southern Burkina Faso.

OBJECTIVES: To evaluate the epidemiological evolution of patients with HIV (PtHIV), between 2002 and 2012, in a day-hospital that became an HIV reference centre for south-west Burkina Faso. MATERIALS AND METHODS: This was a retrospective study of PtHIV followed in the Bobo Dioulasso university hospital since 2002. The study was based on clinical data recorded using ESOPE software and analysed using Excel and SAS. RESULTS: A total of 7320 patients have been treated at the centre since 2002; the active file of patients increased from 147 in 2002 to 3684 patients in 2012. Mean age was stable at 38.4 years and the majority were female (71%). The delay to initiation of antiretroviral (ARV) treatment after HIV diagnosis decreased from 12.9 months in 2002 to 7.2 months in 2012. The percentage of PtHIV lost to follow-up, untreated for HIV and deaths all decreased after 2005. Voluntary anonymous screening and/or an evocative clinical picture were the main reasons for HIV diagnosis, usually at a late stage (41.1% at WHO stage 3). Virological success increased due to a decrease in time to initiation of ARV treatment and an increase in percentage of patients treated (90.5% in 2012, mainly with 1st line drugs). However, there was also a slight increase in the rate of therapeutic failures and the percentage of patients who progressed to 2nd or 3rd line-ARVs. CONCLUSION: Our day-hospital is a good example of the implementation of a specialist centre for the management of PtHIV in a resource-limited country (Burkina Faso).

Key features of intertidal food webs that support migratory shorebirds.

The migratory shorebirds of the East Atlantic flyway land in huge numbers during a migratory stopover or wintering on the French Atlantic coast. The Brouage bare mudflat (Marennes-Oléron Bay, NE Atlantic) is one of the major stopover sites in France. The particular structure and function of a food web affects the efficiency of carbon transfer. The structure and functioning of the Brouage food web is crucial for the conservation of species landing within this area because it provides sufficient food, which allows shorebirds to reach the north of Europe where they nest. The aim of this study was to describe and understand which food web characteristics support nutritional needs of birds. Two food-web models were constructed, based on in situ measurements that were made in February 2008 (the presence of birds) and July 2008 (absence of birds). To complete the models, allometric relationships and additional data from the literature were used. The missing flow values of the food web models were estimated by Monte Carlo Markov Chain--Linear Inverse Modelling. The flow solutions obtained were used to calculate the ecological network analysis indices, which estimate the emergent properties of the functioning of a food-web. The total activities of the Brouage ecosystem in February and July are significantly different. The specialisation of the trophic links within the ecosystem does not appear to differ between the two models. In spite of a large export of carbon from the primary producer and detritus in winter, the higher recycling leads to a similar retention of carbon for the two seasons. It can be concluded that in February, the higher activity of the ecosystem coupled with a higher cycling and a mean internal organization, ensure the sufficient feeding of the migratory shorebirds.

An easily accessible Re-based catalyst for the selective conversion of methanol: evidence for an unprecedented active site structure through combined operando techniques.

Heterogeneous Re/SiO(2) catalysts prepared using a one pot sol-gel synthesis were found to display high activity in the direct, selective methanol conversion to methylal, which is correlated to an unprecedented rhenium oxide structure.

Serologic response to hepatitis B vaccination in HIV-Infected patients with isolated positivity for antibodies to hepatitis B core antigen.

We assessed the safety and immunogenicity of hepatitis B vaccination among 40 human immunodeficiency virus-infected patients with isolated positivity for antibodies to hepatitis B core antigen. No baseline factors were found to be predictive of an anamnestic response, which occurred in 32.5% of the patients. The overall response rate among patients without an anamnestic response was 74.0% after 3-6 vaccine doses.