Measurement of 13CO2 in expired air as an index of compliance to a high carbohydrate diet naturally enriched in 13C.

The aim of this study was to determine whether breath 13CO2 measurements could be used to assess the compliance to a diet containing carbohydrates naturally enriched in 13C. The study was divided into two periods: Period 1 (baseline of 4 days) with low 13C/12C ratio carbohydrates. Period 2 (5 days) isocaloric diet with a high 13C/12C ratio (corn, cane sugar, pineapple, millet) carbohydrates. Measurements were made of respiratory gas exchange by indirect calorimetry, urinary nitrogen excretion and breath 13CO2 every morning in post-absorptive conditions, both in resting state and during a 45-min low intensity exercise (walking on a treadmill). The subjects were 10 healthy lean women (BMI 20.4 +/- 1.7 kg/m2, % body fat 24.4 +/- 1.3%), the 13C enrichment of oxidized carbohydrate and breath 13CO2 were compared to the enrichment of exogenous dietary carbohydrates. At rest the enrichment of oxidized carbohydrate increased significantly after one day of 13C carbohydrate enriched diet and reached a steady value (103 +/- 16%) similar to the enrichment of exogenous carbohydrates. During exercise, the 13C enrichment of oxidized carbohydrate remained significantly lower (68 +/- 17%) than that of dietary carbohydrates. The compliance to a diet with a high content of carbohydrates naturally enriched in 13C may be assessed from the measurement of breath 13CO2 enrichment combined with respiratory gas exchange in resting, postabsorptive conditions.

Activités professionnelles et qualité de l'air des parcs de stationnement couvert : rapport d'expertise collective

[Table des matières] 1. Contexte, objet et modalités de traitement de la saisine. - 2. Préambule. - 3. Caractérisation des parcs de stationnement couverts et de leurs activités professionnelles en France (enquête Afsset). - 4. Observations de terrain et analyse d'activités professionnelles exercées dans les parcs de stationnement couverts (étude Anact). - 5. Evaluation des risques sanitaires. - 6. Recommandations. - Bibliographie. - Annexe 1 : Lettre de saisine. - Annexe 2 : Présentation des positions divergentes. - Annexe 3 : Synthèse des déclarations publiques d'intérêts des experts par rapport au champ de la saisine. - Annexe 4 : Réglementation et recommandations institutionnelles concernant la qualité de l'air dans les parcs de stationnement couverts, et l'hygiène et la sécurité des travailleurs. - Annexe 5 : Etude de coparly sur la mesure de polluants atmosphériques dans les parcs de stationnement - Informations générales. - Annexe 6 : Dépassement des valeurs cibles Afsset" limitant les risques pour la santé des travailleurs dans les parcs de stationnement (Coparly, 2009). - Annexe 7 : Enquête Asset - Méthode d'identification du code NAF le plus adapté. - Annexe 8 : Enquête Afsset - Questionnaire d'enquête. - Annexe 9 : Enquête Afsset - Villes d'implantation des parcs inclus dans l'étude. - Annexe 10 : Rapport de l'Anact : Activité professionnelle et qualité de l'air dans les parcs couverts de stationnement. - Annexe 11 : Résultats de mesures de la campagne du LCPP utilisés pour les scénarios d'exposition. - Annexe 12 : Résultats issus de l'enquête Afsset sur les activités professionnelles exercées dans les parcs de stationnement couverts. - Annexe 13 : Concentrations ubiquitaires dans différents "micro-environnements" (Afsset, 2007). - Annexe 14 : Facteurs d'abattement entre concentrations dans le local d'exploitation et dans le parc. - Annexe 15 : Limites des valeurs toxicologiques de référence (Afsset, 2007). - Annexe 16 : Exemples de solutions pour améliorer la qualité de l'air et réduire l'exposition des travailleurs.

Carbon dioxide in scree slope deposits: A pathway from atmosphere to pedogenic carbonate

A continuum of carbon, from atmospheric CO2 to secondary calcium carbonate, has been studied in a soil associ- ated with scree slope deposits in the Jura Mountains of Switzerland. This approach is based on former studies conducted in other environments. This C continuum includes atmospheric CO2, soil organic matter (SOM), soil CO2, dissolved inorganic carbon (DIC) in soil solutions, and secondary pedogenic carbonate. Soil parameters (pCO2, temperature, pH, Cmin and Corg contents), soil solution chemistry, and isotopic compositions of soil CO2, DIC, carbonate and soil organic matter (δ13CCO2, δ13CDIC, δ13Ccar and δ13CSOM values) have been monitored at different depths (from 20 to 140 cm) over one year. Results demonstrated that the carbon source in secondary carbonate (mainly needle fiber calcite) is related to the dissolved inorganic carbon, which is strongly dependent on soil respiration. The heterotrophic respiration, rather than the limestone parent material, seems to control the pedogenic carbon cycle. The correlation of δ13Corg values with Rock-Eval HI and OI indices demonstrates that, in a soil associated to scree slope deposits, the main process responsible for 13C-enrichment in SOM is related to bac- terial oxidative decarboxylation. Finally, precipitation of secondary calcium carbonate is enhanced by changes in soil pCO2 associated to the convective movement of air masses induced by temperature gradients (heat pump effect) in the highly porous scree slope deposits. The exportation of soil C-leachates from systems such as the one studied in this paper could partially explain the "gap in the European carbon budget" reported by recent studies.

Exposition au fumage involontaire dans l'air intérieur des locaux. Problèmes liés aux mesures de l'exposition à la fumée de tabac

A brief and critical review of the physical and chemical markers of ETS was made as well as the techniques which were used to measure their concentrations in indoor air. Despite the existing data, more investigations and measurements are needed to characterize the exposure to ETS and their health effects.

L'exégèse et l'air du temps

La théologie est-elle une science ? Ce débat n'est pas nouveau, et il accompagne les différentes disciplines de la théologie au moins depuis le siècle des Lumières. Dans la discussion actuelle, par exemple entre théologie et sciences religieuses, les disciplines théologiques qui apparaissent souvent comme les plus "scientifiques" sont les sciences bibliques et l'histoire du christianisme. Il ne fait à mon avis aucun doute qu'il s'agit là des disciplines qui posent le moins problème pour une position qu'on pourrait qualifier de "laïque". Et cependant, ce serait un leurre de croire que ces méthodes sont exemptes de présuppositions théologiques ou idéologiques. Je n'ai pas l'intention d'entrer ici dans le débat sur le problème de l'objectivité de la science, faute de temps et de compétence. J'aimerais plus modestement montrer, à partir de l'exégèse de la Bible hébraïque, l'interconnexion - pas toujours consciente - entre certains modèles exégétiques et les options idéologiques des savants qui défendent ou promeuvent ces modèles.

Hypoglycémie chez des patients porteurs de pompe a insuline [Hypoglycemia in patients treated with an external insulin pump].

Hypoglycemia is a potentially serious complication of insulin therapy. Some insulin-dependent diabetic patients can benefit from continuous subcutaneous insulin infusion therapy (an "insulin pump"), which in most case improves glycemia control and decreases the occurrence of hypoglycemic episodes. However, such events may occur, particularly during initial treatment phases or pregnancy. Severe hypoglycemia is mainly managed by stopping the insulin pump and insuring an adequate carbohydrate intake. Patients with insulin pumps and their entourage should receive specific instruction in the adjustment of pump flow in the presence of dysglycemia-inducing circumstances (illness, physical exertion), as well as in anticipation of high-risk situations, such as motor-vehicle driving.

Interim analysis of the Reitan Catheter Pump (RCP) heart failure efficacy study: RCP improves cardiovascular and renal function in acute decompensated heart failure (ADHF)

Background: The RCP is a 14 French collapsable percutaneous cardiovascular support device positioned in the descending part of the thoracic aorta via the femoral artery. A 10 patient first in man study demonstrated device safety and significant improvement in renal function among high risk PCI patients. We now report haemodynamic and renal efficacy in patients with ADHF.Methods: Prospective non randomised study seeking to recruit 20 patients with ADHF with a need for inotropic or mechanical circulatory support with: i) EF < 30% ii)Cardiac index(CI) < 2.2 L / min / m2 Outcome measures included: 1) Cardiac index (CI) 2) Pulmonary Capillary Wedge Pressure (PCWP) 3) Urine output / serum creatinine 4) Vascular / device complications 5) 30 day mortalityResults: INTERIM ANALYSIS (n=12) The mean age of the study group was 64 years, with a mean baseline creatinine of 193 umol/L, eGFR 38 ml/min. The intended RCP treatment period was 24 hours. During RCP treatment there was a significant mean reduction of PCWP at 4 hours of 17% (25 to 21 mmHg p=0.04). Mean CI increased at 12 hours by 11%, though not reaching significance (1.78 to 1.96 L/min/m2 p=0.08). RCP insertion prompted substantial diuresis. Urine output tripled over the first 12 hours compared to baseline (55 ml/hr vs 213 ml/hr p=0.03). This was associated with significantly improved renal function, a 28% reduction in serum creatinine at 12 hours (193 to 151 umol/L p=0.003), and a increase in eGFR from 38 ml/min to 50 ml/min (p=0.0007). 2 patients previously refused cardiac transplantation were reassessed and successfully transplanted within 9 months of RCP treatment on the basis of demonstrable renal reversibility. There were no vascular or device complications. There were 2 deaths at 30 days, one from multi-organ failure and sepsis, and one from intractable heart failure - neither were device related.Conclusion: RCP support in ADHF patients was associated with improved haemodynamics, and an improvement in renal function. The Reitan Catheter Pump may have a role in providing percutaneous cardiovascular and renal support in the acutely decompensated cardiac patient, and may have a role in suggesting renal reversibility in potential cardiac transplant patients. Further data will be reported at recruitment completion.