Accuracy profile validation of a new analytical method for propane measurement using headspace-gas chromatography-mass spectrometry

Propane can be responsible for several types of lethal intoxication and explosions. Quantifying it would be very helpful to determine in some cases the cause of death. Some gas chromatography-mass spectrometry (GC-MS) methods of propane measurements do already exist. The main drawback of these GC-MS methods described in the literature is the absence of a specific propane internal standard necessary for accurate quantitative analysis. The main outcome of the following study was to provide an innovative Headspace-GC-MS method (HS-GC-MS) applicable to the routine determination of propane concentration in forensic toxicology laboratories. To date, no stable isotope of propane is commercially available. The development of an in situ generation of standards is thus presented. An internal-labeled standard gas (C3DH7) is generated in situ by the stoichiometric formation of propane by the reaction of deuterated water (D2O) with Grignard reagent propylmagnesium chloride (C3H7MgCl). The method aims to use this internal standard to quantify propane concentrations and, therefore, to obtain precise measurements. Consequently, a complete validation with an accuracy profile according to two different guidelines, the French Society of Pharmaceutical Sciences and Techniques (SFSTP) and the Gesellschaft für toxikologische und Forensische Chemie (GTFCh), is presented.

Analytical interference of 4-hydroxy-3-methoxymethamphetamine with the measurement of plasma free normetanephrine by ultra-high pressure liquid chromatography-tandem mass spectrometry.

OBJECTIVES: The diagnosis of pheochromocytoma relies on the measurement of plasma free metanephrines assay whose reliability has been considerably improved by ultra-high pressure liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Here we report an analytical interference occurring between 4-hydroxy-3-methoxymethamphetamine (HMMA), a metabolite of 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy"), and normetanephrine (NMN) since they share a common pharmacophore resulting in the same product ion after fragmentation. DESIGN AND METHODS: Synthetic HMMA was spiked into plasma samples containing various concentrations of NMN and the intensity of the interference was determined by UPLC-MS/MS before and after improvement of the analytical method. RESULTS: Using a careful adjustment of chromatographic conditions including the change of the UPLC analytical column, we were able to distinguish both compounds. HMMA interference for NMN determination should be seriously considered since MDMA activates the sympathetic nervous system and if confounded with NMN may lead to false-positive tests when performing a differential diagnostic of pheochromocytoma.

L'aplicació de la normativa comptable europea en el sector sanitari públic: estudi comparat sobre l'aplicació del Sistema Europeu de Comptes SEC-95 als centres sanitaris del Regne Unit, França i Alemanya

Aquest informe té per objecte analitzar com s'interpreta i aplica la normativa comptable europea (el Sistema Europeu de Comptes SEC-95) en el sector sanitari públic, des d'una perspectiva de Dret comparat. Concretament, l'estudi es centra en l'aplicació del SEC-95 als centres sanitaris del Regne Unit, França i Alemanya, amb la finalitat de poder extreure conclusions que resultin d'utilitat en l'àmbit de les Empreses Públiques i Consorcis (EPIC) del Sistema Sanitari Català.

Measurement of the mechanical power of walking by satellite positioning system (GPS).

PURPOSE: This descriptive article illustrates the application of Global Positioning System (GPS) professional receivers in the field of locomotion studies. The technological challenge was to assess the external mechanical work in outdoor walking. METHODS: Five subjects walked five times during 5 min on an athletic track at different imposed stride frequency (from 70-130 steps x min(-1)). A differential GPS system (carrier phase analysis) measured the variation of the position of the trunk at 5 Hz. A portable indirect calorimeter recorded breath-by-breath energy expenditure. RESULTS: For a walking speed of 1.05 +/- 0.11 m x s(-1), the vertical lift of the trunk (43 +/- 14 mm) induced a power of 46.0 +/- 20.4 W. The average speed variation per step (0.15 +/- 0.03 m x s(-1)) produced a kinetic power of 16.9 +/- 7.2 W. As compared with commonly admitted values, the energy exchange (recovery) between the two energy components was low (39.1 +/- 10.0%), which induced an overestimated mechanical power (38.9 +/- 18.3 W or 0.60 W x kg(-1) body mass) and a high net mechanical efficiency (26.9 +/- 5.8%). CONCLUSION: We assumed that the cause of the overestimation was an unwanted oscillation of the GPS antenna. It is concluded that GPS (in phase mode) is now able to record small body movements during human locomotion, and constitutes a promising tool for gait analysis of outdoor unrestrained walking. However, the design of the receiver and the antenna must be adapted to human experiments and a thorough validation study remains to be conducted.

Caveolin expression changes in the neurovascular unit after juvenile traumatic brain injury: signs of blood-brain barrier healing?

Traumatic brain injury (TBI) is one of the major causes of death and disability in pediatrics, and results in a complex cascade of events including the disruption of the blood-brain barrier (BBB). A controlled-cortical impact on post-natal 17 day-old rats induced BBB disruption by IgG extravasation from 1 to 3 days after injury and returned to normal at day 7. In parallel, we characterized the expression of three caveolin isoforms, cav-1, cav-2 and cav-3. While cav-1 and cav-2 are expressed on endothelial cells, both cav-1 and cav-3 were found to be present on reactive astrocytes, in vivo and in vitro. Following TBI, cav-1 expression was increased in blood vessels at 1 and 7 days in the perilesional cortex. An increase of vascular cav-2 expression was observed 7 days after TBI. In contrast, astrocytic cav-3 expression decreased 3 and 7 days after TBI. Activation of eNOS (via its phosphorylation) was detected 1 day after TBI and phospho-eNOS was detected both in association with blood vessels and with astrocytes. The molecular changes involving caveolins occurring in endothelial cells following juvenile-TBI might participate, independently of eNOS activation, to a mechanism of BBB repair while, they might subserve other undefined roles in astrocytes.

Measurement of β-tryptase in postmortem serum in cardiac deaths. [Measurement of beta-tryptase in postmortem serum in cardiac deaths]

Mast cells are well known for their role in hypersensitivity reactions. However, there is increasing evidence that they might also participate in both developing and weakening atherosclerotic plaques, potentially causing plaque instability. Some clinical studies have therefore postulated the existence of relationships between blood β-tryptase levels and acute coronary syndromes. In this study, we investigated postmortem serum β-tryptase levels in a series of 90 autopsy cases with various degrees of coronary atherosclerosis that had undergone medico-legal investigations. β-tryptase concentrations in these cases were compared to levels observed in 6 fatal anaphylaxis cases following contrast material administration. Postmortem serum β-tryptase concentrations in the anaphylactic deaths ranged from 146 to 979 ng/ml. In 9 out of 90 cases of cardiac deaths, β-tryptase levels were higher than clinical reference values of 11.4 ng/ml and ranged from 21 to 65 ng/ml. These results indicate that increased postmortem serum β-tryptase levels can be observed, though not systematically, in cardiac deaths with varying degrees of coronary atherosclerosis disease, thereby suggesting that mast cell activation in this disease cannot be ascertained by postmortem serum β-tryptase measurements.

L'incontinence urinaire chez des personnes âgées hospitalisées en unité de gériatrie: est-ce vraiment une priorité pour les infirmières [Urinary incontinence in hospitalized geriatric patients : is it really a priority for nurses?].

INTRODUCTION: urinary incontinence (UI) is a phenomenon with high prevalence in hospitalized elderly patients, effecting up to 70% of patients requiring long term care. However, despite the discomfort it causes and its association with functional decline, it seems to be given insufficient attention by nurses in geriatric care. OBJECTIVES: to assess the prevalence of urinary incontinence in geriatric patients at admission and the level of nurse involvement as characterized by the explicit documentation of UI diagnosis in the patient's record, prescription of nursing intervention, or nursing actions related to UI. METHODS: cross-sectional retrospective chart review. One hundred cases were randomly selected from those patients 65 years or older admitted to the geriatric ward of a university hospital. The variables examined included: total and continence scores on the Measure of Functional Independence (MIF), socio-demographic variables, presence of a nursing diagnosis in the medical record, prescription of or documentation of a nursing intervention related to UI. RESULTS: the prevalence of urinary incontinence was 72 % and UI was positively correlated with a low MIF score, age and status of awaiting placement. Of the examined cases, nursing diagnosis of UI was only documented in 1.4 % of cases, nursing interventions were prescribed in 54 % of cases, and at least one nursing intervention was performed in 72 % of cases. The vast majority of the interventions were palliative. DISCUSSION: the results on the prevalence of IU are similar to those reported in several other studies. This is also the case in relation to nursing interventions. In this study, people with UI were given the same care regardless of their MIF score MIF, age or gender. One limitation of this study is that it is retrospective and therefore dependent on the quality of the nursing documentation. CONCLUSIONS: this study is novel because it examines UI in relation to nursing interventions. It demonstrates that despite a high prevalence of UI, the general level of concern for nurses remains relatively low. Individualized care is desirable and clinical innovations must be developed for primary and secondary prevention of UI during hospitalization.

Black culture, white youth: la tradició cultural jamaicana al Regne Unit

Amb aquest projecte es pretén documentar tres dècades d'influència jamaicana en la cultura britànica, a partir de l’arribada del vaixell Empire Windrush al 1948, de la independència de Jamaica al 1962 i fins a finals dels anys setanta, coincidint amb l’arribada del rastafarisme. Es tracta de posar de manifest la contribució cultural i social dels jamaicans que, en gran part, ha ajudat al desenvolupament del Regne Unit.Els sound systems, els segells discogràfics i les seves subsidiàries, les gires i concerts d’artistes jamaicans... són una clara mostra de les aportacions de la comunitat jamaicana al país i que molts cops es posen de manifest amb celebracions tan populars com el famós Carnaval de Notting Hill. I és que la música i la cultura jamaicana és quelcom més del que molts es pensen, no només és Bob Marley i el consum de marihuana.

Performance Measurement for Highway Winter Maintenance Operations, TR-491, 2009

The goal of this research project was to develop a method to measure the performance of a winter maintenance program with respect to the task of providing safety and mobility to the travelling public. Developing these measures required a number of steps, each of which was accomplished. First, the impact of winter weather on safety (crash rates) and mobility (average vehicle speeds were measured by a combination of literature reviews and analysis of Iowa Department of Transportation traffic and Road Weather Information System data. Second, because not all winter storms are the same in their effects on safety and mobility, a method had to be developed to determine how much the various factors that describe a winter storm actually change safety and mobility. As part of this effort a storm severity index was developed, which ranks each winter storm on a scale between 0 (a very benign storm) and 1 (the worst imaginable storm). Additionally a number of methods of modeling the relationships between weather, winter maintenance actions and road surface conditions were developed and tested. The end result of this study was a performance measure based on average vehicle speed. For a given class of road, a maximum expected average speed reduction has been identified. For a given storm, this maximum expected average speed reduction is modified by the storm severity index to give a target average speed reduction. Thus, if for a given road the maximum expected average speed reduction is 20 mph, and the storm severity for a particular storm is 0.6, then the target average speed reduction for that road in that storm is 0.6 x 20 mph or 12 mph. If the average speed on that road during and after the storm is only 12 mph or less than the average speed on that road in good weather conditions, then the winter maintenance performance goal has been met.

Impact of the phosphatidylinositide 3-kinase signaling pathway on the cardioprotection induced by intermittent hypoxia.

BACKGROUND: Exposure to intermittent hypoxia (IH) may enhance cardiac function and protects heart against ischemia-reperfusion (I/R) injury. To elucidate the underlying mechanisms, we developed a cardioprotective IH model that was characterized at hemodynamic, biochemical and molecular levels. METHODS: Mice were exposed to 4 daily IH cycles (each composed of 2-min at 6-8% O2 followed by 3-min reoxygenation for 5 times) for 14 days, with normoxic mice as controls. Mice were then anesthetized and subdivided in various subgroups for analysis of contractility (pressure-volume loop), morphology, biochemistry or resistance to I/R (30-min occlusion of the left anterior descending coronary artery (LAD) followed by reperfusion and measurement of the area at risk and infarct size). In some mice, the phosphatidylinositide 3-kinase (PI3K) inhibitor wortmannin was administered (24 µg/kg ip) 15 min before LAD. RESULTS: We found that IH did not induce myocardial hypertrophy; rather both contractility and cardiac function improved with greater number of capillaries per unit volume and greater expression of VEGF-R2, but not of VEGF. Besides increasing the phosphorylation of protein kinase B (Akt) and the endothelial isoform of NO synthase with respect to control, IH reduced the infarct size and post-LAD proteins carbonylation, index of oxidative damage. Administration of wortmannin reduced the level of Akt phosphorylation and worsened the infarct size. CONCLUSION: We conclude that the PI3K/Akt pathway is crucial for IH-induced cardioprotection and may represent a viable target to reduce myocardial I/R injury.

La Monogamie, ou l'Unité dans le mariage, ouvrage dans lequel on entreprend d'établir... l'exacte... conformité des trois loix, de la nature, de Moïse et de Jésus-Christ sur ce sujet, par M. de Prémontval. Dédié aux dames par son épouse.... Tome 3

Comprend : Épître dédicatoire

La Monogamie, ou l'Unité dans le mariage, ouvrage dans lequel on entreprend d'établir... l'exacte... conformité des trois loix, de la nature, de Moïse et de Jésus-Christ sur ce sujet, par M. de Prémontval. Dédié aux dames par son épouse.... Tome 2

Comprend : Épître dédicatoire

Réactualisation de la douzième conférence de consensus de la Société de réanimation de langue française (SRLF) : infections liées aux cathéters veineux centraux en réanimation [Updating of the 12th consensus conference of the Société de Réanimation de langue française (SRLF) : catheter related infections in Intensive Care unit]

Concerning catheter-related infections, many studies have been conducted until the last consensus conference of the Sociétéde réanimation de langue française (SRLF) in 1994. This text is the synthesis of the considerable amount of work performed by the experts of the society to review recent studies. The experts' texts as well as extensive bibliography are available at http://www.srlf.org.

The Europeanisation of the measurement of diversity in education: a soft instrument of public policy

Faced with an increasing number of data and rankings, the author questions the roles of the different groups of actors who were originally involved in questioning the use of statistical indicators as a means of addressing issues of access to higher education. The comparison and nature of these international (UNESCO, OECD, EUROSTAT) and national (Germany, England, France, Switzerland) indicators in matters of inequalities of access to higher education question the tension between the discourses and the indicators they generate, and their recording at the national level. Who says what and with what consequences? What range of actors are involved in this process? What kind of power relations forms them? The author discusses how the issue of inequalities of access to higher education got on to the agendas of European organisations, identifies the policies that were defined, and sets them against an array of indicators, showing the discrepancy between the discourses and what the indicators reveal, the gap between the recommendations and the available tools. Why is there such a contrast? What are the mechanisms at work? Is it a technical or a political problem? What does this discrepancy reveal as far as national specificities within the construction of social inequalities are concerned?