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Abstract: A high-resolution, full-depth, hydrographic section across Drake Passage with tracers and horizontal velocity measurements was repeated within three weeks in austral summer 2006. In-situ data (temperature, salinity, dissolved-oxygen and horizontal current velocities) are used to determine the location of the fronts and eddies of the Antarctic Circumpolar Current (ACC) inferred by from 7-day composite dynamic topography maps along the transect. Frontal displacements are about 40km (2 stations) along the section. Considerable differences in properties between the two sections are observed throughout the whole water column with values as high as 0.2°C in temperature, 0.01 in salinity, 0.03kgm−3 in neutral density and 10μmolkg−1 in dissolved-oxygen concentration found below a depth of 3000m. Only part of the differences is attributable to frontal or eddy displacements along the section. The other part results from the spatial heterogeneity of water properties upstream the section and the funnelling of the flow due to the topographic constraints of the Shackleton Fracture Zone (SFZ). The considerable short-term differences in water properties in rather large-scale structures that cannot be accounted for by frontal motions along the section call for caution when interpreting differences in hydrographical properties obtained by oceanographic cruises that are years apart in terms of climatic signals. The two sections show efficient ventilation of Antarctic Intermediate Water (AAIW) by Winter Water (WW) in the Yaghan Basin, with an estimated eddy-enhanced subduction rate of over 170myear−1. The SFZ constitutes a barrier, causing the two Southern ACC Fronts (SACCF) branches to separate by about 400km and creating sheltered conditions in partial isolation from the ACC, while promoting an active recirculation region in the Ona Basin. This active recirculation, marked by cyclonic eddies carrying cold, fresh and oxygenated water from south of the Southern Boundary of the ACC, causes effective ventilation of the whole Circumpolar Deep Water (CDW) density range. The differences in small-scale structures between the two sections deserve further analyses. [Copyright &y& Elsevier]

Abstract: Altimetry data have proven themselves essential for the early detection, analysis and monitoring of large scale tropical anomalies associated with El Niño in the Pacific. Warm events in the Atlantic are much weaker than in the Pacific and are partially masked by the strong seasonal cycle. Satellite altimetric data permits one to estimate the zonal sea surface slope variations at the equator in the Atlantic with sufficient accuracy for resolving interannual sea surface slope variations. The altimetry-derived slope is here shown to detect Atlantic warm events. For all warm events, anomalies in sea surface slope tend to lead SST. In the mid-1990s’, the equatorial interannual variability is dominated by 17-month period events which exhibit the structure observed in local coupled ocean–atmosphere warm events (zonal wind stress weakening and zonal surface slope relaxation, warm SST, excess precipitation). The frequency of occurrence of these Atlantic warm events is seen to have increased during the mid-1990s. [Copyright &y& Elsevier]

Introduction L’étude des réactions posturales à une stimulation sensorielle permet de mieux comprendre les stratégies posturales comme nous l’avons proposé après AVC (Bonan et al., 2013). Nous rapportons ici l’analyse chez des PIDC. Matériel et méthode Étude prospective chez 15 contrôles (57 ± 13 ans, 6 M, 9 F) et 15 PIDC (63 ± 15 ans, 13 M, 2 F) avec une comparaison de la déviation moyenne principale du centre de pression (mm) durant la stimulation (35s) sur stabilométrie ; la proprioception stimulée par vibrations tendineuses des triceps suraux (TS) et tibiaux antérieurs (TA) et la vision stimulée par flux optocinétique dans 4 directions (haut, bas, droite, gauche). Résultats Les chutes ont été plus fréquentes chez les PIDC que chez les témoins (expliquant la perte de 31,1 % versus 2,2 % des enregistrements ; p < 000,1), essentiellement en condition visuelle (40 % versus 3,3 % sous optocinétique) notamment en rotation optocinétique vers le bas (16,6/9,5 mm, p = 0,019) et à droite (10/4,8 mm, p = 000,9). Ceci objective l’hypersensibilité aux informations visuelles des sujets PIDC. Cependant, les PIDC restaient sensibles aux stimulations proprioceptives et réagissaient sans différence aux témoins pour la stimulation des TS et de façon plus importante en antépulsion lors de la vibration des TA (13,48/7,89 mm, p = 0,017). Discussion–conclusion Les PIDC sont beaucoup plus sensibles aux informations visuelles, comme attendu, mais restent sensibles aux stimulations proprioceptives malgré les troubles sensitifs, ce qui encourage la rééducation visant à la récupération d’informations proprioceptives plutôt qu’à la compensation par les informations visuelles. [ABSTRACT FROM AUTHOR]

Introduction La variabilité de la marche représente les fluctuations des paramètres spatiotemporels (PST) d’un pas à l’autre. C’est un indicateur sensible des déficits moteurs et de contrôle de l’équilibre dynamique. Le Gait Variability Index (Gouelle et al., 2013), dérivé de neuf PST, a été proposé pour améliorer la quantification de la variabilité de la marche. L’objectif est d’étudier l’index chez des patients cérébrolésés, à vitesse spontanée, puis rapide. Matériel et méthodes Vingt-neuf patients patients cérébrolésés (âge = 65 à 80 ans) et 29 sujets contrôles ont été enregistrés sur un tapis GAITRite ® , à vitesse spontanée, puis rapide. L’évaluation clinique de l’équilibre était réalisée par la Berg Balance Scale et le Rivermead Mobility Index. Résultats Aucune différence n’était retrouvée entre les conditions de marche spontanée et rapide chez les sujets contrôles (GVI : 87,9 ± 11,6 vs. 89,4 ± 12,8). À l’inverse, 20 patients cérébrolésés ont montré une variabilité moindre (GVI plus grand) à vitesse rapide, avec pour 14 d’entre eux une amélioration de la la symétrie spatiale et/ou temporelle de leur marche. Seuls 3 patients ont présenté à la fois une détérioration de la variabilité et de la symétrie à vitesse rapide. Aucune relation n’a été identifiée avec les tests cliniques. Discussion–conclusion Nos résultats montrent que, contrairement à une idée communément admise, la marche rapide n’influence pas négativement la stabilité dynamique du patient cérébrolésé, en accord avec les études montrant que la vitesse confortable de marche n’est pas une vitesse lente. Il semble que lors de l’examen, nombre de patients portent davantage leur attention à la qualité de leur marche au détriment de l’efficience. [ABSTRACT FROM AUTHOR]

Introduction Muscle vibration leads to agonist muscle contraction and antagonist muscle relaxation, this is the Tonic Vibration Reflex (TVR) [1] . Central nervous system interprets tendon vibration as a lengthening of this one inducing a virtual movement sensation [2] . The objective of this study is to observe this effect after stroke. Method Thirty-eight subjects have been evaluated: 19 stroke patients (10 men, 60.7 ± 9.8 years old) and 19 healthy subjects (5 men, 56 ± 11 years old). Vibrators (VibraSens VB200, TechnoConcept) were placed on the biceps brachii and wrist flexors tendons. Each subject received a vibration (80 Hz, 40 s) for each upper limb. An accelerometer was placed on the forearm in order to quantify the TVR with the elbow flexion angle. Movement perception of the subject was highlighted through a perception score created for the study. Subjects were seated on a chair, blindfolded, dangling arm. Results Flexion angle of the elbow (TVR) was identical on the left (32.2 ± 22.9°) and right (35.2 ± 32.2°) healthy subjects upper limb. For stroke patients it was identical on the healthy upper limb (33.1 ± 21.2°) compared to the upper limb of healthy subjects but greatly decreased on the deficient upper limb (9.6 ± 13.7°) of stroke patients compared to their healthy upper limb ( P = 0.0003). Perception score was less important on the hemiplegic side than the healthy side ( P < 0.0001) and was correlated to motor impairment (Fugl-Meyer) ( P < 0.0001, r = 0.687) and spasticity ( P < 0.00001). Anaesthesia was not correlated to a low score of perception, but only 3 subjects were concerned. Conclusion TVR and usual movement illusion under tendon vibration are affected on the hemiplegic side after stroke. Any relationship or not on the observed deficiencies require confirmation with a larger sample. [ABSTRACT FROM AUTHOR]

Introduction L’étude de retour à l’équilibre de la posture debout après stimulation sensorielle permet de mieux comprendre les stratégies posturales après un Accident Vasculaire Cérébral (AVC). Matériel et méthodes Étude prospective 20 sujets sains, 40 AVC (20 droits et 20 gauches). La différence entre la position moyenne du centre de pression (mm) avant et 10 s après stimulation sur une durée de 10 s a été étudiée par stabilométrie. La proprioception était stimulée par vibrations tendineuses des triceps suraux (TS) et tibiaux antérieurs (TA). La vision était stimulée par flux optocinétique dans 4 directions (haut, bas, droite, gauche). Résultats Population d’âge moyen 55 ± 11 ans, sex-ratio 1/1, délai post-AVC de 1,8 ± 1,1 mois. L’analyse porte sur 83 % des tests chez les AVC et 97,5 % des tests chez les sujets sains en raison de la survenue de chutes. Après vibrations tendineuses, la posture des AVC gauches était plus antériorisée que celle des sujets sains quels que soient les tendons vibrés (TS : +11,4/ + 2,5 mm, p = 0,01 et TA : –2,8/–8,4 mm, p = 0,03). Après optocinétique, les AVC gauches présentaient une relatéralisation sur leur membre parétique : après stimulation vers le haut (6,3/–2,7 mm, p = 0,0001), vers le bas (1,9/–2,5 mm, p = 0,02) et vers la droite (13,6/2,4 mm, p = 0,03). Les AVC droits ne présentaient pas de différences significatives de leur posture par rapport aux sujets sains. Discussion–conclusion À l’arrêt des stimulations sensorielles, la posture debout était modifiée par rapport à l’état de base uniquement chez les AVC gauches par rapport au sujets sains. [ABSTRACT FROM AUTHOR]

Platelet concentrate (PC) is an alternative therapy to treat mastitis in dairy cattle and is an alternative treatment for reproduction problems such as endometritis. Unfortunately, double-centrifugation processing methods described are time-consuming, require specialized laboratory equipment, and are usually done in a heterologous way, which risks herd health. To overcome this limitation, we evaluated single-step bovine PC processing methods readily applicable to a farm setting using an autologous conditioned plasma (ACP) production system. We investigated the hematologic findings, cytokines, and growth factors of the obtained PC samples. Autologous conditioned plasma was prepared using whole blood (WB) from 4 cows (group 1) using single-step centrifugation and 16 different processing methods. The 2 protocols that yielded the highest ratio of platelet to white blood cell (WBC) concentration were ACP-1 [720 × g (2,200 rpm), 5 min] and ACP-2 [929 × g (2,500 rpm), 3 min]. They were subsequently reproduced and compared using WB from 8 cows (group 2). Hematologic findings were quantified, IL-1β (cytokine) and growth factors [platelet-derived growth factor (PDGF), transforming growth factor (TGF)-β, bovine fibroblast growth factor (b-FGF)] were measured, and enrichment factors were compared between samples and processing methods. Hematological characteristics and platelet enrichment varied markedly among tested protocols and all were statistically different from WB. Protocol ACP-2 resulted in significantly greater platelet enrichment (mean 169% of WB) than ACP-1 (125% of WB). We found no significant difference between the 2 ACP preparation protocols with regard to leukocyte reduction (7.53–9.75% WBC compared with WB) or growth factor enrichment (124–125% PDGF, 95–100% TGF-β, 102–104% b-FGF, and 56–74% IL-1β compared with WB). In conclusion, both ACP protocols yielded a platelet concentration shown to promote healing for clinical applications in cattle, and the ACP-2 protocol resulted in a greater degree of platelet enrichment. Therefore, this protocol could be used for ACP production for clinical applications in cattle. [Display omitted] [ABSTRACT FROM AUTHOR]

Introduction AMBA is a bombesin analogue that binds to GRPr. In a mouse model of estrogen-dependent human breast cancer, we tested whether 68 Ga-AMBA can be used for PET detection of GRPr-expressing tumors and could be more accurate than 18 F-FDG to monitor tumor response to hormone therapy. Methods The radiolabeling of 68 Ga-AMBA was automated using a R&D Synchrom module. ZR75-1, a breast cancer cell line, was xenografted in nude mice. 68 Ga-AMBA tumor uptake was compared with that of 18 F-FDG before and after treatment with tamoxifen. Results AMBA was 68 Ga-radiolabelled in 30 min with 95.3% yield and purity ≥ 98%. Prior to treatment, 68 Ga-AMBA was highly concentrated into tumors (tumor to non-tumor ratio = 2.4 vs. 1.3 with 18 F-FDG). With tamoxifen treatment (n = 6) 68 Ga-AMBA uptake plateaued after 1 week and decreased after 2 weeks, with a significant reduction compared to controls (n = 4). In contrast the effect of tamoxifen treatment could not be appreciated using 18 F-FDG. Conclusions 68 Ga-AMBA appeared better than 18 F-FDG to visualize and monitor the response to hormone treatment in this breast cancer model. [ABSTRACT FROM AUTHOR]

Abstract: A multiparametric analysis is applied on the ANT-XXIII/3 bottle data to determine the spreading and mixing of water masses across Drake Passage during January–February 2006, focusing our interest on the flow of the deep water masses. Mixing proportions are quantified along both the southward and northward journeys between the tip of South America and the Antarctic Peninsula. The method is sensitive enough to detect a marked variability in the flow pathways of the Circumpolar Deep Water, the Southeast Pacific Deep Water (SPDW) and the Weddell Sea Deep Water at the intersection of the Shackleton Fracture Zone (SFZ) and the West Scotia Ridge (WSR) between the southward and northward journeys. Indeed the presence of a sharp meander of the southern branch of the Polar Front (PFS) together with the displacement of the northern branch of the Southern Antarctic Circumpolar Current Front (SACCFN) above the complex bathymetric structure of the WSR induced a strong perturbation in the deep flow field during the southward journey. The height of the SFZ crests clearly sets the lower limit of the SPDW in the Ona Basin. An enhanced δ3He signature is confined to the north of the Polar Front between 55.5°S and 56.5°S in the 1500–2200m depth range. It clearly indicates the signature of the core of the Southeast Pacific Deep Slope Water. The entry pathway in the ACC of the SPDSW during ANT-XXIII/3 was farther to the south off the continental slope of South America than it was during the WOCE A21 expedition in 1990, probably due to the sharp changes in the slope orientation at the extreme tip of the South America. [Copyright &y& Elsevier]

Introduction La faible qualité des acquisitions réalisées par la Wii Board Balance est souvent mise en avant comme le principal obstacle à son utilisation comme plate-forme de force pour l’évaluation de l’équilibre. Une nouvelle approche est proposée, utilisant des méthodes de traitement du signal avancée afin d’améliorer la qualité des enregistrements ainsi que des méthodes de fouille de données pour en améliorer l’interprétabilité. Matériel et méthode Deux cents sujets de plus de 70 ans atteints de différents syndrômes liés à l’équilibre, dont 35 chuteurs, ont été enregistrés deux fois pendant 25 secondes, une fois les yeux ouverts, une fois les yeux fermés. Les signaux ont été traités pour compenser les limitations de la plate-forme de force, puis analysés par des méthodes récentes de fouille de données. Finalement, un score entre zéro et cent est associé de manière automatique à l’enregistrement. Résultats L’aire sous la courbe de spécificité représentant le score d’équilibre en fonction des chutes réelles des patients est supérieure à 0,75, soit un résultat très significatif. Discussion–conclusion Les signaux de la Wii Board balance peuvent être traités et analysés de manière à aider à la détection de troubles de l’équilibre pouvant conduire à des chutes. [ABSTRACT FROM AUTHOR]

Introduction A few studies have found short-term effects of tendon vibration therapy on upper limb function in chronic hemiplegia [1,2] . We report the effect of tendon vibrations of the elbow and wrist flexor muscles on recovery of the upper limb in a recent hemiplegic patient. Observation A 69-year-old woman was admitted to our department for right hemiplegia and aphasia after a left middle cerebral artery (MCA) stroke and a left cerebellar infarct secondary to cardiac arrhythmia. Initial NIHSS 22/44. Motor function on upper limb was limited to slight abduction and elevation of the shoulder, slight flexion of the wrist and elbow. The initial Functional Independence Measure score was 38/126. Intensive classical reeducation was started with little progress of upper limb recovery despite upper limb suspension, bimanual work and mirror therapy for 1 month. Two months after the stroke, the vibration program began. Evaluation using Fugl-Meyer assessment (FMA) for the upper limb, the Action Research Arm Test (ARAT) and the modified Tardieu Scale was performed at days 0, 7, 21, 28 and 35. The tolerance and feasibility were studied. Vibrations (80 Hz) were applied on right distal biceps brachii, flexor carpi radialis and ulnaris muscle tendons during 16 min, twice a day, 5 days a week for 2 weeks on days 7 to 21. No side effects or pain were reported. The FMA score increased 6 points the first week, 9 points during the vibration period, 9 new points the third week, and then stabilized. The ARAT score increased from 0 to 11 during the vibration period and reach 24 at D35. Discussion Tendon vibration seemed to give a new impetus to motor recovery in this patient and leads to the elaboration of a controlled trial to assess its real effectiveness in subacute stroke. [ABSTRACT FROM AUTHOR]

Background The Romberg test, with the subject standing and with eyes closed, gives diagnostic arguments for a proprioceptive disorder. Closing the eyes is also used in balance rehabilitation as a main way to stimulate neural plasticity with proprioceptive, vestibular and even cerebellar disorders. Nevertheless, standing and walking with eyes closed or with eyes open in the dark are certainly 2 different tasks. We aimed to compare walking with eyes open, closed and wearing black or white goggles in healthy subjects. Methods A total of 50 healthy participants were randomly divided into 2 protocols and asked to walk on a 5-m pressure-sensitive mat, under 3 conditions: (1) eyes open (EO), eyes closed (EC) and eyes open with black goggles (BG) and (2) EO, EO with BG and with white goggles (WG). Gait was described by velocity (m·s −1 ), double support (% gait cycle), gait variability index (GVI/100) and exit from the mat (%). Analysis involved repeated measures Anova, Holm-Sidak's multiple comparisons test for parametric parameters (GVI) and Dunn's multiple comparisons test for non-parametric parameters. Results As compared with walking with EC, walking with BG produced lower median velocity, by 6% (EO 1.26; BG 1.01 vs EC 1.07 m·s −1 , P = 0.0328), and lower mean GVI, by 8% (EO 91.8; BG 66.8 vs EC 72.24, P = 0.009). Parameters did not differ between walking under the BG and WG conditions. Conclusion The goggle task increases the difficulty in walking with visual deprivation compared to the Romberg task, so the goggle task can be proposed to gradually increase the difficulty in walking with visual deprivation (from eyes closed to eyes open in black goggles). [ABSTRACT FROM AUTHOR]