Acute post-exercise oxygen uptake, hormone and plasma metabolite response in obese men.

This study aimed to compare oxygen uptake (  V˙O2), hormone and plasma metabolite responses during the 30 min after submaximal incremental exercise (Incr) performed at the same relative/absolute exercise intensity and duration in lean (L) and obese (O) men. Eight L and 8 O men (BMI: 22.9±0.4; 37.2±1.8 kg · m(-2)) completed Incr and were then seated for 30 min.   V˙O2 was monitored during the first 10 min and from the 25-30(th) minutes of recovery. Blood samples were drawn for the determination of hormone (catecholamines, insulin) and plasma metabolite (NEFA, glycerol) concentrations. Excess post-exercise oxygen consumption (EPOC) magnitude during the first 10 min was similar in O and in L (3.5±0.4; 3.4±0.3 liters, respectively, p=0.86). When normalized to percent change (  V˙O2END=100%), %   V˙O2END during recovery was significantly higher from 90-120 s in O than in L (p≤0.04). There were no significant differences in catecholamines (p≥0.24), whereas insulin was significantly higher in O than in L during recovery (p=0.01). The time-course of glycerol was similar from 10-30 min of recovery (-42% for L; -41% for O, p=0.85), whereas significantly different patterns of NEFA were found from 10-30 min of recovery between groups (-18% for L; +8% for O, p=0.03). Despite similar EPOC, a difference in   V˙O2 modulation between groups was observed, likely due to faster initial rates of   V˙O2 decline in L than in O. The different patterns of NEFA between groups may suggest a lower NEFA reesterification during recovery in O, which was not involved in the rapid EPOC component.

Falls efficacy predicts functional status on month after discharge in elderly patients undergoing post-accute rehabilitation

Objective: To investigate the relationship between falls efficacy at admission and functional status reported one month after discharge from post-acute rehabilitation in a cohort of elderly patients. Methods: Participants were elderly patients admitted to postacute rehabilitation in an academic geriatric facility. Data on demographics and affective status were collected upon admission; functional status and gait speed were measured at admission and at discharge; self-reported functional status and history of falls since discharge were collected one month after discharge (follow-up). Falls efficacy was measured using the Fall Efficacy Scale, that assesses confidence in performing 12 activities of daily living without falling (range 0 to 100, higher score indicating higher confidence). Patients were classified using the median FES score at baseline (95) as cut-off to divide the population into "confident" and "fearful" groups. Results: Participants' (N=180, mean age 81.3±7.1 years, 75.6% women) mean FES score was 92.3±8.7 at baseline (range 60-100). Basic ADL score averaged 3.5±1.6 at baseline, 4.7±1.3 at discharge, and 5.5±0.7 at follow-up (self-reported). Baseline FES score was positively correlated with basic ADL at follow-up (rho=0.35, p<.001). At follow-up, 58.7% of the patients were fully independent in basic ADL, this proportion being significantly higher in confident than fearful patients (70.7% vs 42.4%, p<.001). Compared to confident patients, those fearful had significantly lower odds (OR 0.3, 95%CI 0.2-0.6, p<.001) to report full independence at follow-up. This relationship remained (adjOR = 0.4, 95%CI 0.2-0.8, p=.01) after controlling for demographics, baseline gait speed, depressive symptoms, functional status at discharge, and history of falls since discharge. Conclusion: In this cohort of older rehab patients, poor falls efficacy at admission was associated with lower function reported one month after discharge even after controlling for initial mobility performance and functional status at discharge. Further studies should determine whether interventions aiming at falls efficacy improvement will also result in improved function in fearful subjects undergoing rehabilitation.

Effect of hormone replacement therapy on vasomotor function of the coronary microcirculation in post-menopausal women with medically treated cardiovascular risk factors.

Aims The aim of this study was to evaluate the effect of hormone replacement therapy (HRT) on coronary vasomotor function in post-menopausal women (PM) with medically treated cardiovascular risk factors (RFs) in a cross-sectional and a longitudinal follow-up (FU) study. Methods and results Myocardial blood flow (MBF) response to cold pressor testing (CPT) and during pharmacologically induced hyperaemia was measured with positron emission tomography in pre-menopausal women (CON), in PM with HRT and without HRT, and repeated in PM after a mean FU of 24 +/- 14 months. When compared with CON at baseline, the endothelium-related change in MBF (DeltaMBF) to CPT progressively declined in PM with HRT and without HRT (0.35 +/- 0.23 vs. 0.24 +/- 0.20 and 0.16 +/- 0.12 mL/g/min; P = 0.171 and P = 0.021). In PM without HRT and in those with HRT at baseline but with discontinuation of HRT during FU, the endothelium-related DeltaMBF to CPT was significantly less at FU than at baseline (0.05 +/- 0.19 vs. 0.16 +/- 0.12 and -0.03 +/- 0.14 vs. 0.25 +/- 0.18 mL/g/min; P = 0.023 and P = 0.001), whereas no significant change was observed in PM with HRT (0.19 +/- 0.22 vs. 0.23 +/- 0.22 mL/g/min; P = 0.453). Impaired hyperaemic MBFs when compared with CON were not significantly altered from those at baseline exam. Conclusion Long-term administration of oestrogen may contribute to maintain endothelium-dependent coronary function in PM with medically treated cardiovascular RFs.

Red blood cell-derived microparticles isolated from blood units initiate and propagate thrombin generation.

BACKGROUND: Red blood cell-derived microparticles (RMPs) are small phospholipid vesicles shed from RBCs in blood units, where they accumulate during storage. Because microparticles are bioactive, it could be suggested that RMPs are mediators of posttransfusion complications or, on the contrary, constitute a potential hemostatic agent. STUDY DESIGN AND METHODS: This study was performed to establish the impact on coagulation of RMPs isolated from blood units. Using calibrated automated thrombography, we investigated whether RMPs affect thrombin generation (TG) in plasma. RESULTS: We found that RMPs were not only able to increase TG in plasma in the presence of a low exogenous tissue factor (TF) concentration, but also to initiate TG in plasma in absence of exogenous TF. TG induced by RMPs in the absence of exogenous TF was neither affected by the presence of blocking anti-TF nor by the absence of Factor (F)VII. It was significantly reduced in plasma deficient in FVIII or F IX and abolished in FII-, FV-, FX-, or FXI-deficient plasma. TG was also totally abolished when anti-XI 01A6 was added in the sample. Finally, neither Western blotting, flow cytometry, nor immunogold labeling allowed the detection of traces of TF antigen. In addition, RMPs did not comprise polyphosphate, an important modulator of coagulation. CONCLUSIONS: Taken together, our data show that RMPs have FXI-dependent procoagulant properties and are able to initiate and propagate TG. The anionic surface of RMPs might be the site of FXI-mediated TG amplification and intrinsic tenase and prothrombinase complex assembly.

Nonoccupational HIV post-exposure prophylaxis: a 10-year retrospective analysis.

BACKGROUND: We conducted a retrospective analysis of administration of nonoccupational HIV post-exposure prophylaxis (nPEP) in a single centre where tracing and testing of the source of exposure were carried out systematically over a 10-year period. METHODS: Files of all nPEP requests between 1998 and 2007 were reviewed. Characteristics of the exposed and source patients, the type of exposure, and clinical and serological outcomes were analysed. RESULTS: nPEP requests increased by 850% over 10 years. Among 910 events, 58% were heterosexual exposures, 15% homosexual exposures, 6% sexual assaults and 20% nonsexual exposures. In 208 events (23%), the source was reported to be HIV positive. In the remaining cases, active source tracing enabled 298 HIV tests to be performed (42%) and identified 11 HIV infections (3.7%). nPEP was able to be avoided or interrupted in 31% of 910 events when the source tested negative. Of 710 patients who started nPEP, 396 (56%) reported side effects, among whom 39 (5%) had to interrupt treatment. There were two HIV seroconversions, and neither was attributed to nPEP failure. CONCLUSIONS: nPEP requests increased over time. HIV testing of the source person avoided nPEP in 31% of events and was therefore paramount in the management of potential HIV exposures. Furthermore, it allowed active screening of populations potentially at risk for undiagnosed HIV infection, as shown by the increased HIV prevalence in these groups (3.7%) compared with a prevalence of 0.3% in Switzerland as a whole.

Long-term monitoring of post-stroke plasticity after transient cerebral ischemia in mice using in vivo and ex vivo diffusion tensor MRI.

WE USED A MURINE MODEL OF TRANSIENT FOCAL CEREBRAL ISCHEMIA TO STUDY: 1) in vivo DTI long-term temporal evolution of the apparent diffusion coefficient (ADC) and diffusion fractional anisotropy (FA) at days 4, 10, 15 and 21 after stroke 2) ex vivo distribution of a plasticity-related protein (GAP-43) and its relationship with the ex vivo DTI characteristics of the striato-thalamic pathway (21 days). All animals recovered motor function. In vivo ADC within the infarct was significantly increased after stroke. In the stroke group, GAP-43 expression and FA values were significantly higher in the ipsilateral (IL) striatum and contralateral (CL) hippocampus compared to the shams. DTI tractography showed fiber trajectories connecting the CL striatum to the stroke region, where increased GAP43 and FA were observed and fiber tracts from the CL striatum terminating in the IL hippocampus.Our data demonstrate that DTI changes parallel histological remodeling and recovery of function.

Chemical and isotopic equilibrium between CO2 and CH4 in fumarolic gas discharges: Generation of CH4 in arc magmatic-hydrothermal systems

The chemical and isotopic composition of fumarolic gases emitted from Nisyros Volcano, Greece, and of a single gas sample from Vesuvio, Italy, was investigated in order to determine the origin of methane (CH,) within two subduction-related magmatic-hydrothermal environments. Apparent temperatures derived from carbon isotope partitioning between CH4 and CO2 of around 340degreesC for Nisyros and 470degreesC for Vesuvio correlate well with aquifer temperatures as measured directly and/or inferred from compositional data using the H2O-H-2-CO2-CO-CH4 geothermometer. Thermodynamic modeling reveals chemical equilibrium between CH4, CO2 and H2O implying that carbon isotope partitioning between CO2 and CH, in both systems is controlled by aquifer temperature. N-2/(3) He and CH4/(3) He ratios of Nisyros fumarolic gases are unusually low for subduction zone gases and correspond to those of midoceanic ridge environments. Accordingly, CH4 may have been primarily generated through the reduction of CO, by H, in the absence of any organic matter following a Fischer-Tropsch-type reaction. However, primary occurrence of minor amounts of thermogenic CH4 and subsequent re-equilibration with co-existing CO2 cannot be ruled out entirely- CO2/He-3 ratios and delta(13)C(CO2) values imply that the evolved CO2 either derives from a metasomatized mantle or is a mixture between two components, one outgassing from an unaltered mantle and the other released by thermal breakdown of marine carbonates. The latter may contain traces of organic matter possibly decomposing to CH4 during thermometamorphism. Copyright (C) 2004 Elsevier Ltd.

Inferring the mode of origin of polyploid species from next-generation sequence data.

Many eukaryote organisms are polyploid. However, despite their importance, evolutionary inference of polyploid origins and modes of inheritance has been limited by a need for analyses of allele segregation at multiple loci using crosses. The increasing availability of sequence data for nonmodel species now allows the application of established approaches for the analysis of genomic data in polyploids. Here, we ask whether approximate Bayesian computation (ABC), applied to realistic traditional and next-generation sequence data, allows correct inference of the evolutionary and demographic history of polyploids. Using simulations, we evaluate the robustness of evolutionary inference by ABC for tetraploid species as a function of the number of individuals and loci sampled, and the presence or absence of an outgroup. We find that ABC adequately retrieves the recent evolutionary history of polyploid species on the basis of both old and new sequencing technologies. The application of ABC to sequence data from diploid and polyploid species of the plant genus Capsella confirms its utility. Our analysis strongly supports an allopolyploid origin of C. bursa-pastoris about 80 000 years ago. This conclusion runs contrary to previous findings based on the same data set but using an alternative approach and is in agreement with recent findings based on whole-genome sequencing. Our results indicate that ABC is a promising and powerful method for revealing the evolution of polyploid species, without the need to attribute alleles to a homeologous chromosome pair. The approach can readily be extended to more complex scenarios involving higher ploidy levels.

Le gradient entre la pression pulmonaire artérielle diastolique et la pression pulmonaire d'occlusion est important dans l'évaluation des hypertensions pulmonaires post- capillaires

Les hypertensions pulmonaires post-capillaires sont définies par une pression artérielle moyenne (PAPm) ≥ 25mmHg et une pression pulmonaire d'occlusion (PAPO) > 15mmHg. Une augmentation de la PAP peut être soit passive, transmission rétrograde de l'augmentation de la pression du coeur gauche ( gradient transpulmonaire GTP ≤ 12mmHg), soit active, élévation hors de proportion de la PAP due à une augmentation du tonus vasculaire et un remodelage vasculaire (GTP > 12mmHg). Le gradient entre la pression artérielle diastolique (PAPd) et la PAPO, qui est normal (≤ 5mmHg) dans les HP post-capillaires, n'est actuellement plus utilisé dans le diagnostic et l'évaluation des HP dans la dernière classification de 2008 (Dana Point 2008). But : - analyse des données cliniques, échocardiographiques et hémodynamiques des HP post-capillaires des patients référés dans un centre de référence d'HP - évaluer le rôle du gradient PAPd-PAPO dans la prise en charge des HP Méthode : Nous avons analysé de manière rétrospective les données cliniques, hémodynamiques et échocardiographiques des patients qui ont été diagnostiqué pour une HP au moyen d'un cathétérisme cardiaque entre janvier 2009 et juin 2011 au centre de référence d'HP du Centre Hospitalier Universitaire Vaudois (CHUV). Résultats: - 40% des patients ont les critères pour une HP post-capillaire - 33% des patients ont une HP qui répond à la définition d'HP "hors de propotion" avec un GTP > 12mmHg - 74% des patients avec HP post-capillaire ont une cardiopathie gauche associée avec des signes échocardiographiques de dysfonction diastolique - Sur les 27 patients avec une HP du groupe 2, 44% ont plusieurs facteurs de risque (FR) pour une HP - 75% de ces patients avec une cardiopathie gauche ainsi qu'un autre FR pour une HP ont un gradient PAPd-PAPO > 5 mmHg versus 8% de ceux qui n'ont pas d'autre FR (p-value 0.0075) Conclusion : Les HP post-capillaires sont fréquentes chez les patients adressés au centre de référence d'HP pour une suspicion d'HP. Dans notre cohorte 85% des patients avec HP post-capillaire ont une HP hors de proportion dont 44% ont un FR non cardiaque susceptible d'être à l'origine de l'HP. Le gradient PAPd-PAPO semble être un meilleur facteur discriminant que le GTP pour la caractérisation et la classification des HP.