Utilisation de la PCR-RFLP sur de l'ADN chloro-plastique pour l'étude des relations phylogénétiques au sein du genre Phaseolus

Phylogenetic relationships among 74 accessions belonging to six species of Phaseolus are investigated using variation in chloroplast DNA assessed according to a PCR-RFLP protocol. Three fragments of chloroplast DNA are amplified using universal primers, and then digested with 10 restriction enzymes. Thirty-six haplotypes are identified on the basis of the polymorphism in fragment number and size. Three main phylogenetic groups, strongly supported through bootstrap analysis, are identified: (1) accessions from Phaseolus lunatus and Phaseolus xolocotzii; (2) accessions from Phaseolus glabellus; (3) accessions from Phaseolus vulgaris, Phaseolus polyanthus and Phaseolus coccineus. Within the third group, accessions of Phaseolus coccineus are scattered along the phylogenetic tree, which provides some evidence that coccineus accessions are paraphyletic with respect to Phaseolus vulgaris and Phaseolus polyanthus. An analysis of molecular variance applied on four species show that they are significantly differentiated with 79% of molecular variance among species and 21% within species. The results agree with previous investigations on chloroplast DNA variation in the genus Phaseolus, and suggest that PCRRFLP methods, which are technically less labour-intensive than previous methods, are of great value for phylogenetic investigations at the generic level

Thermodynamics of an ideal generalized gas:II Means of order α\alpha

The property that power means are monotonically increasing functions of their order is shown to be the basis of the second laws not only for processes involving heat conduction but also for processes involving deformations. In an $L$-potentail equilibration the final state will be one of maximum entropy, while in an entropy equilibrium the final state will be one of minimum $L$. A metric space is connected with the power means, and the distance between means of different order is related to the Carnot efficiency. In the ideal classical gas limit, the average change in the entropy is shown to be proportional to the difference between the Shannon and R\'enyi entropies for nonextensive systems that are multifractal in nature. The $L$-potential, like the internal energy, is a Schur convex function of the empirical temperature, which satisfies Jensen's inequality, and serves as a measure of the tendency to uniformity in processes involving pure thermal conduction.Comment: 8 page

Astrogliopathy predominates the earliest stage of corticobasal degeneration pathology.

Animal models have shown that tau seeding and propagation are strain- and neural network-specific. The study of preclinical cases is valuable to gain insights into early pathological features of corticobasal degeneration and its progression. Three preclinical corticobasal degeneration cases and six age-matched end-stage corticobasal degeneration cases were included in this study. Tau immunohistochemistry performed in 20 brain regions and quantitative assessment of regional tau load using image analysis were performed. Semi-quantitative grading of tau-positive cellular lesions and neuronal loss in the frontal, parietal and temporal cortices, striatum, substantia nigra and subthalamic nucleus were assessed. All preclinical cases were clinically asymptomatic but had widespread tau lesions in the typically affected regions in corticobasal degeneration and the pathognomonic astrocytic plaques were the most prominent lesion type in the anterior frontal and striatal regions. Mean total tau load (sum of all regional tau load) of end-stage corticobasal degeneration cases were nine times greater than that of the preclinical cases (P = 0.04) and less tau load was found in all regions of the preclinical cases. An anterior-to-posterior tau load ratio in the frontal cortex in preclinical cases was 12-fold greater than in end-stage corticobasal degeneration cases. Relatively greater tau burden in the anterior frontal cortex, striatum and subthalamic nucleus suggests the striatal afferent connection to the dorsolateral prefrontal cortex and basal ganglia circuitry are the earliest neural network connections affected by corticobasal degeneration-related tau pathology. Differential distribution of the tau pathology to selective cortical regions in these preclinical cases implies phenotypic presentation may be predetermined at a very early stage of the disease process. Neuronal loss of the substantia nigra was either absent or very mild in the preclinical cases and was moderate to severe in end-stage corticobasal degeneration cases (P < 0.05). Our findings suggest that a threshold of pathological burden in the ‘right’ anatomical regions needs to be reached before the onset of clinical symptoms. The early prominence of the astrocytic plaques in relation to sparse neuronal lesions leads one to speculate that corticobasal degeneration may begin as an astrogliopathy at a very early disease stage but neuronal lesions gradually take over as the predominant lesion type in advanced disease

PREDICT-PD: Identifying risk of Parkinson's disease in the community: methods and baseline results

To present methods and baseline results for an online screening tool to identify increased risk for Parkinson's disease (PD) in the UK population

Improved ventricular function during inhalation of PGI(2) aerosol partly relies on enhanced myocardial contractility

Inhaled prostacyclin (PGI(2)) aerosol induces selective pulmonary vasodilation. Further, it improves right ventricular ( RV) function, which may largely rely on pulmonary vasodilation, but also on enhanced myocardial contractility. We investigated the effects of the inhaled PGI(2) analogs epoprostenol (EPO) and iloprost (ILO) on RV function and myocardial contractility in 9 anesthetized pigs receiving aerosolized EPO (25 and 50 ng center dot kg(-1) center dot min(-1)) and, consecutively, ILO (60 ng center dot kg(-1) center dot min(-1)) for 20 min each. We measured pulmonary artery pressure ( PAP), RV ejection fraction (RVEF) and RV end-diastolic-volume (RV-EDV), and left ventricular end-systolic pressure-volume-relation (end-systolic elastance, E-es). EPO and ILO reduced PAP, increased RVEF and reduced RVEDV. E-es was enhanced during all doses tested, which reached statistical significance during EPO25ng and ILO, but not during EPO50ng. PGI(2) aerosol enhances myocardial contractility in healthy pigs, contributing to improve RV function. Copyright (C) 2005 S. Karger AG, Basel

National priority setting partnership using a Delphi consensus process to develop neonatal research questions suitable for practice-changing randomised trials in the UK

BACKGROUND: The provision of neonatal care is variable and commonly lacks adequate evidence base; strategic development of methodologically robust clinical trials is needed to improve outcomes and maximise research resources. Historically, neonatal research topics have been selected by researchers; prioritisation processes involving wider stakeholder groups have generally identified research themes rather than specific questions amenable to interventional trials. OBJECTIVE: To involve stakeholders including parents, healthcare professionals and researchers to identify and prioritise research questions suitable for answering in neonatal interventional trials in the UK. DESIGN: Research questions were submitted by stakeholders in population, intervention, comparison, outcome format through an online platform. Questions were reviewed by a representative steering group; duplicates and previously answered questions were removed. Eligible questions were entered into a three-round online Delphi survey for prioritisation by all stakeholder groups. PARTICIPANTS: One hundred and eight respondents submitted research questions for consideration; 144 participants completed round one of the Delphi survey, 106 completed all three rounds. RESULTS: Two hundred and sixty-five research questions were submitted and after steering group review, 186 entered into the Delphi survey. The top five ranked research questions related to breast milk fortification, intact cord resuscitation, timing of surgical intervention in necrotising enterocolitis, therapeutic hypothermia for mild hypoxic ischaemic encephalopathy and non-invasive respiratory support. CONCLUSIONS: We have identified and prioritised research questions suitable for practice-changing interventional trials in neonatal medicine in the UK at the present time. Trials targeting these uncertainties have potential to reduce research waste and improve neonatal care

Web-based assessment of Parkinson's prodromal markers identifies GBA variants.

Identifying those “at risk” of Parkinson’s disease (PD) is a priority and a key strategy for testing neuroprotective agents. PREDICT-PD is a pilot cohort study in which healthy UK adults are screened online (www.predictpd.com) with a questionnaire that ascertains the presence of early phenotypic features and risk factors, based on systematic review