Changes in Aortic Pulse Wave Velocity in Hypertensive Postmenopausal Women: Comparison Between a Calcium Channel Blocker vs Angiotensin Receptor Blocker Regimen.

J Clin Hypertens (Greenwich). 2012;14:773-778. ©2012 Wiley Periodicals, Inc. Postmenopausal women are at greater risk for hypertension-related cardiovascular disease. Antihypertensive therapy may help alleviate arterial stiffness that represents a potential modifiable risk factor of hypertension. This randomized controlled study investigated the difference between an angiotensin receptor blocker and a calcium channel blocker in reducing arterial stiffness. Overall, 125 postmenopausal hypertensive women (age, 61.4±6 years; systolic blood pressure/diastolic blood pressure [SBP/DBP], 158±11/92±9 mm Hg) were randomized to valsartan 320 mg±hydrochlorothiazide (HCTZ) (n=63) or amlodipine 10 mg±HCTZ (n=62). The primary outcome was carotid-to-femoral pulse wave velocity (PWV) changes after 38 weeks of treatment. Both treatments lowered peripheral blood pressure (BP) (-22.9/-10.9 mm Hg for valsartan and -25.2/-11.7 mm Hg for amlodipine, P=not significant) and central BP (-15.7/-7.6 mm Hg for valsartan and -19.2/-10.3 mm Hg for amlodipine, P<.05 for central DBP). Both treatments similarly reduced the carotid-femoral PWV (-1.9 vs -1.7 m/s; P=not significant). Amlodipine was associated with a higher incidence of peripheral edema compared with the valsartan group (77% vs 14%, P<.001). BP lowering in postmenopausal women led to a reduction in arterial stiffness as assessed by PWV measurement. Both regimens reduced PWV to a similar degree after 38 weeks of treatment despite differences in central BP lowering, suggesting that the effect of valsartan on PWV is mediated through nonhemodynamic effects.

Detection of plant-modulated alterations in antifungal gene expression in Pseudomonas fluorescens CHA0 on roots by flow cytometry.

The biocontrol activity of the root-colonizing Pseudomonas fluorescens strain CHA0 is largely determined by the production of antifungal metabolites, especially 2,4-diacetylphloroglucinol. The expression of these metabolites depends on abiotic and biotic environmental factors, in particular, elements present in the rhizosphere. In this study, we have developed a new method for the in situ analysis of antifungal gene expression using flow cytometry combined with green fluorescent protein (GFP)-based reporter fusions to the phlA and prnA genes essential for the production of the antifungal compounds 2,4-diacetylphloroglucinol and pyrrolnitrin, respectively, in strain CHA0. Expression of phlA-gfp and prnA-gfp in CHA0 cells harvested from the rhizosphere of a set of plant species as well as from the roots of healthy, leaf pathogen-attacked, and physically stressed plants were analyzed using a FACSCalibur. After subtraction of background fluorescence emitted by plant-derived particles and CHA0 cells not carrying the gfp reporters, the average gene expression per bacterial cell could be calculated. Levels of phlA and prnA expression varied significantly in the rhizospheres of different plant species. Physical stress and leaf pathogen infection lowered phlA expression levels in the rhizosphere of cucumber. Our results demonstrate that the newly developed approach is suitable to monitor differences in levels of antifungal gene expression in response to various plant-derived factors. An advantage of the method is that it allows quantification of bacterial gene expression in rhizosphere populations at a single-cell level. To our best knowledge, this is the first study using flow cytometry for the in situ analysis of biocontrol gene expression in a plant-beneficial bacterium in the rhizosphere.

Debris flows as a factor of hillslope evolution controlled by a continuous or a pulse process?

Flood effectiveness observations imply that two families of processes describe the formation of debris flow volume. One is related to the rainfall?erosion relationship, and can be seen as a gradual process, and one is related to additional geological/geotechnical events, those named hereafter extraordinary events. In order to discuss the hypothesis of coexistence of two modes of volume formation, some methodologies are applied. Firstly, classical approaches consisting in relating volume to catchments characteristics are considered. These approaches raise questions about the quality of the data rather than providing answers concerning the controlling processes. Secondly, we consider statistical approaches (cumulative number of events distribution and cluster analysis) and these suggest the possibility of having two distinct families of processes. However the quantitative evaluation of the threshold differs from the one that could be obtained from the first approach, but they all agree in the sense of the coexistence of two families of events. Thirdly, a conceptual model is built exploring how and why debris flow volume in alpine catchments changes with time. Depending on the initial condition (sediment production), the model shows that large debris flows (i.e. with important volume) are observed in the beginning period, before a steady-state is reached. During this second period debris flow volume such as is observed in the beginning period is not observed again. Integrating the results of the three approaches, two case studies are presented showing: (1) the possibility to observe in a catchment large volumes that will never happen again due to a drastic decrease in the sediment availability, supporting its difference from gradual erosion processes; (2) that following a rejuvenation of the sediment storage (by a rock avalanche) the magnitude?frequency relationship of a torrent can be differentiated into two phases, the beginning one with large and frequent debris flow and a later one with debris flow less intense and frequent, supporting the results of the conceptual model. Although the results obtained cannot identify a clear threshold between the two families of processes, they show that some debris flows can be seen as pulse of sediment differing from that expected from gradual erosion.

The connectome viewer toolkit: an open source framework to manage, analyze, and visualize connectomes.

Advanced neuroinformatics tools are required for methods of connectome mapping, analysis, and visualization. The inherent multi-modality of connectome datasets poses new challenges for data organization, integration, and sharing. We have designed and implemented the Connectome Viewer Toolkit - a set of free and extensible open source neuroimaging tools written in Python. The key components of the toolkit are as follows: (1) The Connectome File Format is an XML-based container format to standardize multi-modal data integration and structured metadata annotation. (2) The Connectome File Format Library enables management and sharing of connectome files. (3) The Connectome Viewer is an integrated research and development environment for visualization and analysis of multi-modal connectome data. The Connectome Viewer's plugin architecture supports extensions with network analysis packages and an interactive scripting shell, to enable easy development and community contributions. Integration with tools from the scientific Python community allows the leveraging of numerous existing libraries for powerful connectome data mining, exploration, and comparison. We demonstrate the applicability of the Connectome Viewer Toolkit using Diffusion MRI datasets processed by the Connectome Mapper. The Connectome Viewer Toolkit is available from http://www.cmtk.org/

Contributions of pitch and bandwidth to sound-induced enhancement of visual cortex excitability in humans.

Multisensory interactions have been documented within low-level, even primary, cortices and at early post-stimulus latencies. These effects are in turn linked to behavioral and perceptual modulations. In humans, visual cortex excitability, as measured by transcranial magnetic stimulation (TMS) induced phosphenes, can be reliably enhanced by the co-presentation of sounds. This enhancement occurs at pre-perceptual stages and is selective for different types of complex sounds. However, the source(s) of auditory inputs effectuating these excitability changes in primary visual cortex remain disputed. The present study sought to determine if direct connections between low-level auditory cortices and primary visual cortex are mediating these kinds of effects by varying the pitch and bandwidth of the sounds co-presented with single-pulse TMS over the occipital pole. Our results from 10 healthy young adults indicate that both the central frequency and bandwidth of a sound independently affect the excitability of visual cortex during processing stages as early as 30 msec post-sound onset. Such findings are consistent with direct connections mediating early-latency, low-level multisensory interactions within visual cortices.

Auditory-somatosensory multisensory interactions are spatially modulated by stimulated body surface and acoustic spectra

Previous research has provided inconsistent results regarding the spatial modulation of auditory-somatosensory interactions. The present study reports three experiments designed to investigate the nature of these interactions in the space close to the head. Human participants made speeded detection responses to unimodal auditory, somatosensory, or simultaneous auditory-somatosensory stimuli. In Experiment 1, electrocutaneous stimuli were presented to either earlobe, while auditory stimuli were presented from the same versus opposite sides, and from one of two distances (20 vs. 70cm) from the participant's head. The results demonstrated a spatial modulation of auditory-somatosensory interactions when auditory stimuli were presented from close to the head. In Experiment 2, electrocutaneous stimuli were delivered to the hands, which were placed either close to or far from the head, while the auditory stimuli were again presented at one of two distances. The results revealed that the spatial modulation observed in Experiment 1 was specific to the particular body part stimulated (head) rather than to the region of space (i.e. around the head) where the stimuli were presented. The results of Experiment 3 demonstrate that sounds that contain high-frequency components are particularly effective in eliciting this auditory-somatosensory spatial effect. Taken together, these findings help to resolve inconsistencies in the previous literature and suggest that auditory-somatosensory multisensory integration is modulated by the stimulated body surface and acoustic spectra of the stimuli presented.

La pertinence en science forensique. Une (en)quête épistémologique et empirique

A criminal investigation requires to search and to interpret vestiges of a criminal act that happened in a past time. The forensic investigator arises in this context as a critical reader of the investigation scene, in search of physical traces that should enable her to tell a story of the offence/crime which allegedly occurred. The challenge of any investigator is to detect and recognise relevant physical traces in order to provide forensic clues for investigation and intelligence purposes. Inspired by this obser- vation, the current research focuses on the following questions : What is a relevant physical trace? And, how does the forensic investigator know she is facing one ? The interest of such questions is to provide a definition of a dimension often used in forensic science but never studied in its implications and operations. This doctoral research investigates scientific paths that are not often explored in forensic science, by using semiotic and sociological tools combined with statistical data analysis. The results are shown following a semiotic path, strongly influenced by Peir- ce's studies, and a second track, called empirical, where investigations data were analysed and forensic investigators interviewed about their work practices in the field. By the semiotic track, a macroscopic view is given of a signification process running from the discove- red physical trace at the scene to what is evaluated as being relevant for the investigator. The physical trace is perceived in the form of several signs, whose meaning is culturally codified. The reasoning should consist of three main steps : 1- What kind of source does the discovered physical trace refer to ? 2- What cause/activity is at the origin of this source in the specific context of the case ? 3- What story can be told from these observations ? The stage 3 requires to reason in creating hypotheses that should explain the presence of the discovered trace coming from an activity ; the specific activity that is related to the investigated case. To validate this assumption, it would depend on their ability to respond to a rule of relevancy. The last step is the symbolisation of the relevancy. The rule would consist of two points : the recognition of the factual/circumstantial relevancy (Is the link between the trace and the case recognised with the formulated hypothesis ? ) and appropriate relevancy (What investment is required to collect and analyse the discovered trace considering the expected outcome at the investigation/intelligence level?). This process of meaning is based on observations and a conjectural reasoning subject to many influences. In this study, relevancy in forensic science is presented as a conventional dimension that is symbolised and conditioned by the context, the forensic investigator's practice and her workplace environment (culture of the place). In short, the current research states relevancy results of the interactions between parameters from situational, structural (or organisational) and individual orders. The detection, collection and analysis of relevant physical traces at scenes depends on the knowledge and culture mastered by the forensic investigator. In the study of the relation relevant trace-forensic investigator, this research introduces the KEE model as a conceptual map that illustrates three major areas of forensic knowledge and culture acquisition, involved in the research and evaluation of the relevant physical trace. Through the analysis of the investigation data and interviews, the relationship between those three parameters and the relevancy was highlighted. K, for knowing, embodies a rela- tionship to the immediate knowledge allowing to give an overview of the reality at a specific moment ; an important point since relevancy is signified in a context. E, for education, is considered through its relationship with relevancy via a culture that tends to become institutionalised ; it represents the theoretical knowledge. As for the parameter E, for experience, it exists in its relation to relevancy in the adjustments of the strategies of intervention (i.e a practical knowledge) of each practitioner having modulated her work in the light of success and setbacks case after case. The two E parameters constitute the library resources for the semiotic recognition process and the K parameter ensures the contextualisation required to set up the reasoning and to formulate explanatory hypotheses for the discovered physical traces, questioned in their relevancy. This research demonstrates that the relevancy is not absolute. It is temporal and contextual; it is a conventional and relative dimension that must be discussed. This is where the whole issue of the meaning of what is relevant to each stakeholder of the investigation process rests. By proposing a step by step approach to the meaning process from the physical trace to the forensic clue, this study aims to provide a more advanced understanding of the reasoning and its operation, in order to streng- then forensic investigators' training. This doctoral research presents a set of tools critical to both pedagogical and practical aspects for crime scene management while identifying key-influences with individual, structural and situational dimensions. - Une enquête criminelle consiste à rechercher et à faire parler les vestiges d'un acte incriminé passé. L'investigateur forensique se pose dans ce cadre comme un lecteur critique des lieux à la recherche de traces devant lui permettre de former son récit, soit l'histoire du délit/crime censé s'être produit. Le challenge de tout investigateur est de pouvoir détecter et reconnaître les traces dites pertinentes pour fournir des indices forensiques à buts d'enquête et de renseignement. Inspirée par un tel constat, la présente recherche pose au coeur de ses réflexions les questions suivantes : Qu'est-ce qu'une trace pertinente ? Et, comment fait le forensicien pour déterminer qu'il y fait face ? L'intérêt de tels questionnements se comprend dans la volonté de définir une dimension souvent utili- sée en science forensique, mais encore jamais étudiée dans ses implications et fonctionnements. Cette recherche se lance dans des voies d'étude encore peu explorées en usant d'outils sémiotiques et des pratiques d'enquêtes sociologiques combinés à des traitements statistiques de données. Les résultats sont représentés en suivant une piste sémiotique fortement influencée par les écrits de Peirce et une seconde piste dite empirique où des données d'interventions ont été analysées et des investigateurs forensiques interviewés sur leurs pratiques de travail sur le terrain. Par la piste sémiotique, une vision macroscopique du processus de signification de la trace en élément pertinent est représentée. La trace est perçue sous la forme de plusieurs signes dont la signification est codifiée culturellement. Le raisonnement se formaliserait en trois principales étapes : 1- Quel type de source évoque la trace détectée? 2- Quelle cause/activité est à l'origine de cette source dans le contexte précis du cas ? 3- Quelle histoire peut être racontée à partir de ces observations ? Cette dernière étape consiste à raisonner en créant des hypothèses devant expliquer la présence de la trace détectée suite à une activité posée comme étant en lien avec le cas investigué. Pour valider ces hypothèses, cela dépendrait de leur capacité à répondre à une règle, celle de la pertinence. Cette dernière étape consiste en la symbolisation de la pertinence. La règle se composerait de deux points : la reconnaissance de la pertinence factuelle (le lien entre la trace et le cas est-il reconnu dans l'hypothèse fournie?) et la pertinence appropriée (quel est l'investissement à fournir dans la collecte et l'exploitation de la trace pour le bénéfice attendu au niveau de l'investigation/renseignement?). Tout ce processus de signification se base sur des observations et un raisonnement conjectural soumis à de nombreuses influences. Dans cette étude, la pertinence en science forensique se formalise sous les traits d'une dimension conventionnelle, symbolisée, conditionnée par le contexte, la pratique de l'investigateur forensique et la culture du milieu ; en somme cette recherche avance que la pertinence est le fruit d'une interaction entre des paramètres d'ordre situationnel, structurel (ou organisationnel) et individuel. Garantir la détection, la collecte et l'exploitation des traces pertinentes sur les lieux dépend de la connaissance et d'une culture maîtrisées par le forensicien. Dans l'étude du rapport trace pertinente-investigateur forensique, la présente recherche pose le modèle SFE comme une carte conceptuelle illustrant trois grands axes d'acquisition de la connaissance et de la culture forensiques intervenant dans la recherche et l'évaluation de la trace pertinente. Par l'analyse des données d'in- terventions et des entretiens, le rapport entre ces trois paramètres et la pertinence a été mis en évidence. S, pour savoir, incarne un rapport à la connaissance immédiate pour se faire une représentation d'une réalité à un instant donné, un point important pour une pertinence qui se comprend dans un contexte. F, pour formation, se conçoit dans son rapport à la pertinence via cette culture qui tend à s'institutionnaliser (soit une connaissance théorique). Quant au paramètre E, pour expérience, il se comprend dans son rapport à la pertinence dans cet ajustement des stratégies d'intervention (soit une connaissance pratique) de chaque praticien ayant modulé leur travail au regard des succès et échecs enregistrés cas après cas. F et E formeraient la bibliothèque de ressources permettant le processus de reconnaissance sémiotique et S assurerait la contextualisation nécessaire pour poser le raisonnement et formuler les hypothèses explicatives pour les traces détectées et questionnées dans leur pertinence. Ce travail démontre que la pertinence n'est pas absolue. Elle est temporelle et contextuelle, c'est une dimension conventionnelle relative et interprétée qui se doit d'être discutée. C'est là que repose toute la problématique de la signification de ce qui est pertinent pour chaque participant du processus d'investigation. En proposant une lecture par étapes du processus de signification depuis la trace à l'indice, l'étude vise à offrir une compréhension plus poussée du raisonnement et de son fonctionnement pour renforcer la formation des intervenants forensiques. Cette recherche présente ainsi un ensemble d'outils critiques à portée tant pédagogiques que pratiques pour la gestion des lieux tout en identifiant des influences-clé jouées par des dimensions individuelles, structurelles et situationnelles.

Low adiponectin is associated with increased ambulatory pulse pressure and activation of the renin-angiotensin system in subjects of African descent

Purpose: Adiponectin, arterial stiffness, as well components of the renin-angiotensin system are associated with cardiovascular risk. This study was aimed to investigate whether plasma adiponectin was directly linked with pulse pressure (PP), as a marker for arterial stiffness, and the renin-angiotensin system (RAS). Methods and materials: A family-based study in subjects of African descent enriched with hypertensive patients was carried out in the Seychelles. Fasting plasma adiponectin was determined by ELISA, plasma renin activity according to the antibody-trapping principle and plasma aldosterone by radioimmunoassay. Daytime ambulatory blood pressure (BP) was measured using Diasys Integra devices. PP was calculated as the difference between systolic and diastolic BP. The association of adiponectin with PP, plasma renin activity and plasma aldosterone were analyzed using generalized estimating equations with a gaussian family link and an exchangeable correlation structure to account for familial aggregation. Results: Data from 335 subjects from 73 families (152 men, 183 women) were available. Men and women had mean (SD) age of 45.4 ± 11.1 and 47.3 ± 12.4 years, BMI of 26.3 ± 4.4 and 27.8 ± 5.1 kg/m2, daytime systolic/diastolic BP of 132.6 ± 15.4 / 86.1 ± 10.9 and 130 ± 17.6 / 83.4 ± 11.1 mmHg, and daytime PP of 46.5 ± 9.9 and 46.7 ± 10.7 mmHg, respectively. Plasma adiponectin was 4.4± 3.04 ng/ml in men and 7.39 ± 5.44 ng/ml in women (P <0.001). After adjustment for age, sex and BMI, log-transformed adiponectin was negatively associated with daytime PP (-0.009 ± 0.003, P = 0.004), plasma renin activity (-0.248 ± 0.080, P = 0.002) and plasma aldosterone (-0.004 ± 0.002, P = 0.014). Conclusion: Low adiponectin is associated with increased ambulatory PP and RAS activation in subjects of African descent. Our data are consistent with the observation that angiotensin II receptor blockers increase adiponectin in humans.

Diffusion tensor echo planar imaging using surface coil transceiver with a semiadiabatic RF pulse sequence at 14.1T.

Diffusion magnetic resonance studies of the brain are typically performed using volume coils. Although in human brain this leads to a near optimal filling factor, studies of rodent brain must contend with the fact that only a fraction of the head volume can be ascribed to the brain. The use of surface coil as transceiver increases Signal-to-Noise Ratio (SNR), reduces radiofrequency power requirements and opens the possibility of parallel transmit schemes, likely to allow efficient acquisition schemes, of critical importance for reducing the long scan times implicated in diffusion tensor imaging. This study demonstrates the implementation of a semiadiabatic echo planar imaging sequence (echo time=40 ms, four interleaves) at 14.1T using a quadrature surface coil as transceiver. It resulted in artifact free images with excellent SNR throughout the brain. Diffusion tensor derived parameters obtained within the rat brain were in excellent agreement with reported values.

Owl pellets as a source of DNA for genetic studies of small mammals.

Owl pellets contain a good skeletal record of the small mammals consumed, and correspond to the undigested portions of prey which are regurgitated. These pellets are easy to find at the roosting site of owls. As it has been demonstrated that amplifiable DNA can be isolated from ancient bone remains, the possibility of using owl pellets as a source of DNA for small mammal genetics studies via the polymerase chain reaction has been investigated. The main uncertainties when isolating DNA from such a material are firstly the possibility that the extracted DNA would be too degraded during the digestion in the stomach of the owl, and secondly that extensive cross-contaminations could occur among the different prey consumed. The results obtained clearly demonstrate that cross-contamination does not occur, and that mitochondrial and nuclear DNA can be amplified using skulls of small mammals found in owl pellets as a source of DNA. The relative efficiency of two methods of DNA extraction is estimated and discussed. Thus, owl pellets represent a non-invasive sampling technique which provides a valuable source of DNA for studying population genetics of small mammals.

Cellular source and mechanisms of high transcriptome complexity in the Mammalian testis.

Understanding the extent of genomic transcription and its functional relevance is a central goal in genomics research. However, detailed genome-wide investigations of transcriptome complexity in major mammalian organs have been scarce. Here, using extensive RNA-seq data, we show that transcription of the genome is substantially more widespread in the testis than in other organs across representative mammals. Furthermore, we reveal that meiotic spermatocytes and especially postmeiotic round spermatids have remarkably diverse transcriptomes, which explains the high transcriptome complexity of the testis as a whole. The widespread transcriptional activity in spermatocytes and spermatids encompasses protein-coding and long noncoding RNA genes but also poorly conserves intergenic sequences, suggesting that it may not be of immediate functional relevance. Rather, our analyses of genome-wide epigenetic data suggest that this prevalent transcription, which most likely promoted the birth of new genes during evolution, is facilitated by an overall permissive chromatin in these germ cells that results from extensive chromatin remodeling.

Changes in Aortic Pulse Wave Velocity in Hypertension Post-Menopausal Women: Comparison Between Calcium Channel Blocker (CCB) Vs Angiotensin Receptor Blocker (ARB) Regimen

Objective: To compare effects of a non-renin-angiotensin system (RAS) blocker, using a CCB, or a RAS blocker, using an ARB regimen on the arterial stiffness reduction in postmenopausal hypertensive women. Methods: In this prospective study, a total of 125 hypertensive women (age: 61.4_6 yrs; 98% Caucasian; BW: 71.9_14 kg; BMI: 27.3_5 kg/m2; SBP/ DBP: 158_11/92_9 mmHg) were randomized between ARB (valsartan 320mg_HCTZ) and CCB (amlodipine 10mg _ HCTZ). The primary outcome was carotid-femoral pulse wave velocity (PWV) changes after 38 weeks of treatment. Results: There were no significant differences in baseline demographic data between the two groups. Both treatments effectively lowered BP at the end of the study with similar (p>0.05) reductions in the valsartan (_22.9/_10.9 mmHg) and amlodipine based (_25.2/_11.7 mmHg) treatment groups. Despite a lower (p<0.05 for DBP) central SBP/DBP in the CCB group (_19.2/_10.3 mmHg) compared to the valsartan group (_15.7/_7.6 mmHg) at week 38, a similar reduction in carotid-femoral PWV (_1.7 vs _1.9 m/sec; p>0.05) was observed between both groups. The numerically larger BP reduction observed in the CCB group was associated with a much higher incidence of peripheral edema (77% vs 14%) than the valsartan group. Conclusion: In summary, BP lowering in postmenopausal women led to a reduction in arterial stiffness assessed by PWV measurement. Both regimens reduced PWV at 38 weeks of treatment to a similar degree, despite differences in BP lowering suggesting that the effect of RAS blockade to influence PWV may partly be independent of BP.

Shielding requirements in helical tomotherapy.

Helical tomotherapy is a relatively new intensity-modulated radiation therapy (IMRT) treatment for which room shielding has to be reassessed for the following reasons. The beam-on-time needed to deliver a given target dose is increased and leads to a weekly workload of typically one order of magnitude higher than that for conventional radiation therapy. The special configuration of tomotherapy units does not allow the use of standard shielding calculation methods. A conventional linear accelerator must be shielded for primary, leakage and scatter photon radiations. For tomotherapy, primary radiation is no longer the main shielding issue since a beam stop is mounted on the gantry directly opposite the source. On the other hand, due to the longer irradiation time, the accelerator head leakage becomes a major concern. An analytical model based on geometric considerations has been developed to determine leakage radiation levels throughout the room for continuous gantry rotation. Compared to leakage radiation, scatter radiation is a minor contribution. Since tomotherapy units operate at a nominal energy of 6 MV, neutron production is negligible. This work proposes a synthetic and conservative model for calculating shielding requirements for the Hi-Art II TomoTherapy unit. Finally, the required concrete shielding thickness is given for different positions of interest.