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Background We report an enhancement of the dorsal roots on gadolinium-enhanced cervical magnetic resonance imaging (MRI) in a patient with acute autonomic and sensory neuropathy (AASN). Case presentation A 38-year-old woman visited our university hospital for dizziness and fainting while rising from sitting or lying down and a tingling sensation in the whole body, including her limbs, torso, and abdomen, which was sustained for 15 days. The patient had hyperalgesia in nearly her entire body and slight motor weakness in her bilateral upper and lower limbs. Autonomic dysfunction was confirmed using autonomic testing. Furthermore, the nerve conduction study showed an absence of sensory nerve action potentials in all evaluated peripheral nerves. Cervical MRI was performed 18 days after dysautonomia onset. In the axial T1-gadolinum-enhanced MRIs, enhancement in cervical ventral and dorsal nerve roots and the posterior column of the spinal cord were observed, and the axial T2-weighted MRI showed high signal intensity in the posterior column of the cervical spinal cord. Considering the clinical, electrophysiological and imaging findings, the patient was diagnosed with AASN. A total dose of 90 g (2 g/kg) of intravenous immunoglobulin was administered over 5 days. At the follow-up at 4 years after AASN symptom onset, the hyperalgesia and orthostatic hypotension symptoms improved. However, her systolic blood pressure intermittently decreased to Conclusion Gadolinium-enhanced MRI may facilitate the accurate and prompt diagnosis of AASN.

Shoulder ultrasound (US) examination is the most frequent US application in the musculoskeletal field. This review article critically analyzes the scientific literature concerning new horizons, pitfalls, and advantages in shoulder US and its translation to clinical practice. Although sonographic appearance of shoulder pathologies such as tendinopathy, tendon tear, bursal pathologies, degenerative changes, calcifications, joint abnormalities, and different signs is important, awareness of different shoulder US pitfalls, dynamic assessments, axillary recess evaluation, post-surgical changes, elastography, and other new advancements in this field will be essential for the expert sonographer. Acknowledgment of new techniques and pitfalls in the shoulder US will improve diagnosis and treatment of different shoulder pathologies.

Background We imaged the corticospinal tract (CST) and corticoreticular pathway (CRP) using diffusion tensor tractography (DTT) to evaluate the cause of muscle weakness in a patient who was exposed to high-voltage electricity. Case presentation A 39-year-old man presented with quadriparesis after high-voltage electrical shock from power lines while working about 5.8 years ago. The electrical current entered through the left hand and exited through the occipital area of the head. The degree of weakness on bilateral upper and lower extremities was 3–4 on the Medical Research Council strength scale. Diffusion tensor imaging (DTI) was performed 5.8 years after onset. The CST and CRP were depicted by placing two regions of interest for each neural tract on the two-dimensional fractional anisotropy color map. DTT of the DTI scan showed that the bilateral CST and CRP were thinned compared to those of the healthy control subject. On the nerve conduction test, abnormal findings suggesting peripheral nerve lesion were not observed. Therefore, injury of bilateral CST and CRP seems to have contributed to our patient’s weakness after the electrical shock. Conclusion Depiction of neural tracts in the brain using DTT can assist in the accurate and detailed evaluation of the cause of neural deficit after electrical injury.

Little is known about the role of islet delta cells in regulating blood glucose homeostasis in vivo. Delta cells are important paracrine regulators of beta cell and alpha cell secretory activity, however the structural basis underlying this regulation has yet to be determined. Most delta cells are elongated and have a well-defined cell soma and a filopodia-like structure. Using in vivo optogenetics and high-speed Ca2+ imaging, we show that these filopodia are dynamic structures that contain a secretory machinery, enabling the delta cell to reach a large number of beta cells within the islet. This provides for efficient regulation of beta cell activity and is modulated by endogenous IGF-1/VEGF-A signaling. In pre-diabetes, delta cells undergo morphological changes that may be a compensation to maintain paracrine regulation of the beta cell. Our data provides an integrated picture of how delta cells can modulate beta cell activity under physiological conditions., Pancreatic islets are composed of alpha-, beta-, as well as delta-cells and appropriate regulation of glucose homeostasis relies on auto- and paracrine cellular communication. Here, the authors study the role of delta-cell filopodia in this context by employing optogenetic and calcium imaging approaches.

Time-lapse fluorescence microscopy is an essential technique for quantifying various characteristics of cellular processes, i.e. cell survival, migration, and differentiation. To perform high-throughput quantification of cellular processes, nuclei segmentation and tracking should be performed in an automated manner. Nevertheless, nuclei segmentation and tracking are challenging tasks due to embedded noise, intensity inhomogeneity, shape variation as well as a weak boundary of nuclei. Although several nuclei segmentation approaches have been reported in the literature, dealing with embedded noise remains the most challenging part of any segmentation algorithm. We propose a novel denoising algorithm, based on sparse coding, that can both enhance very faint and noisy nuclei signal but simultaneously detect nuclei position accurately. Furthermore our method is based on a limited number of parameters, with only one being critical, which is the approximate size of the objects of interest. We also show that our denoising method coupled with classical segmentation method works properly in the context of the most challenging cases. To evaluate the performance of the proposed method, we tested our method on two datasets from the cell tracking challenge. Across all datasets, the proposed method achieved satisfactory results with 96:96% recall for the C. elegans dataset. Besides, in the Drosophila dataset, our method achieved very high recall (99:3%).

To evaluate the efficacy and safety of induction in women with a single prior Caesarean section.This was a cohort study in which we included all singleton pregnancies in patients with a single prior Caesarean who delivered between 2007 and 2012. Methods of induction were ocytocic infusion plus amniotomy (if Bishop score ≥6) or insertion of a Foley catheter (Bishop6).Of the 2,075 patients included, 806 (38.8 %) had an elective repeat Caesarean, 1,045 (50.4 %) went into spontaneous labour, 89 (4.3 %) were induced by artificial rupture of the membranes and infusion of ocytocics and 135 (6.5 %) were induced using a Foley catheter. Rates of vaginal delivery were 79.2, 79.8 and 43.7 %, respectively. Six cases of uterine rupture were reported in the group of patients who went into spontaneous labour. There was no difference between groups with regard to neonatal morbidity. On multivariate analysis, risk factors for Caesarean delivery were macrosomia (OR 2.04, 95 % CI 1.31-3.18) and induction by Foley catheter (OR 3.73, 95 % CI 2.47-5.62); protective factors were previous vaginal delivery (OR 0.41, 95 % CI 0.29-0.57) and cervical dilatation (OR 0.84, 95 % CI 0.78-0.91).Uterine induction after a single Caesarean section with ocytocic infusion and amniotomy where the cervix is favourable does not appear to entail any significant added risk in terms of maternal or foetal morbidity. Foley catheter induction is a reasonable option if the cervix is not ripe.

International audience; Dual endosymbioses involving methane- and sulphur-oxidizing bacteria occur in the gills of several species of mussels from deep-sea hydrothermal vents and cold seeps. Variations of total and relative abundances of symbionts depending on local environmental parameters are not yet understood, due to a lack of reliable quantification of bacteria in the host tissue. Here, we report the first attempt to quantify volumes occupied by each type of symbiont in bacteriocyte sections from a vent mussel, Bathymodiolus azoricus, using fluorescence in situ hybridization (FISH) coupled to three dimentional microscopy and image analysis carried out by a dedicated software, which we developed. Bacteriocytes from mussels recovered at different vent sites displayed significantly different abundances of bacteria. Specimens kept in aquaria at atmospheric pressure and exposed to an artificial pulse of sulphur displayed an increase in absolute and relative abundance of sulphur oxidizers within their bacteriocytes. Distributions of all measured parameters fitted normal distributions, indicating that bacteriocytes from a specimen tend to display similar behaviours. This study shows that symbiont volume quantification is tractable using 3D FISH, and confirms the impact of local environmental parameters on symbiont abundances.

Ophiolites are found all over the world: from the Alps to the Himalayas, in Cuba, Papua-New Guinea, New Caledonia, Newfoundland, etc. They are composed of hard rocks—basalt, dolerite, gabbro and peridotite, which are formed at the mid-oceanic ridges, with specific ridge-related tectonic fracturing and intense hydrothermal alteration. Their geological and thus their hydrogeological properties differ from those of both granite or “classical” gabbro and “classical” basaltic lava. A conceptual hydrogeological model of these hard-rock aquifers was developed based on the convergent results of a multidisciplinary approach at several spatial scales, from rock-sample (centimetre) to catchment (kilometre), on well-preserved ophiolite rocks in Oman. In ophiolite rocks, groundwater circulation takes place mostly in the fissured near-surface horizon (≈50 m thick), and, to a lesser degree, in the tectonic fractures. Hydrograph analysis (Water Resour Res 34:233–240, 1977), interpretation of numerous pumping tests using both classical Theis and dual porosity models [Water Resour Res 32:2733–2745, 1996; Comput Geosci J (in press)], and mercury porosity and hydraulic conductivity lab-measurements support the aquifer parameter estimates. The hydraulic conductivity K of the fissured horizon is estimated at 10−5 to 10−6 m/s for gabbro and dolerite, and 10−7 m/s for peridotite. The storage coefficient S of the peridotite aquifer is estimated at 10−3 and appears to be controlled mainly by microcracks (20 to 100 μm wide). Tectonic fractures in the ophiolite have similar hydrodynamic properties regardless of lithology (10−1

Objectives Second-generation triptans are believed to have fewer cardiovascular effects than sumatriptan. This was investigated in vivo by comparing the vascular effects of equipotent therapeutic dosages of selective 5-HT1B/1D-receptor agonists. Methods Sixteen patients with migraine headaches completed a double-blind, placebo-controlled, four-way crossover study. With ultrasonography and applanation tonometry used 1.5 hours after the oral intake of sumatriptan (50 mg), rizatriptan (10 mg), zolmitriptan (2.5 mg), or placebo arterial vessel wall properties, blood flow and pressure waveforms were measured in common carotid, brachial, and temporal arteries. At the brachial artery, flow-induced vasodilation (an endothelium-dependent process) was evaluated, and blood pressures were recorded. Results Mean arterial pressure, 91 ± 2 mm Hg after placebo, increased (P < .05) by 4% to 6% after administration of each triptan. Each active treatment decreased (P < .001) both brachial and carotid artery diameter. Isobaric compliance of the brachial artery, 0.077 ± 0.010 mm2/kPa after placebo, decreased (P < .01) by 11% ± 8%, 11% ± 11%, and 23% ± 7% after administration of sumatriptan, rizatriptan, and zolmitriptan, respectively. Isobaric compliance of the carotid artery was 1.31 ± 0.10 mm2/kPa after placebo (no change). Zolmitriptan was the only triptan that decreased temporal artery diameter significantly (by 12% ± 3%, P < .001). The resistance of the temporal artery vascular bed increased after administration of sumatriptan (by 26% ± 11%, P < .05) and zolmitriptan (by 40% ± 9%, P = .001). Flow-induced vasodilation was unaffected. Conclusions Selective 5-HT1B/1D-receptor agonists induce vasoconstriction and decrease compliance of conduit arteries. These effects are more pronounced at muscular (temporal, brachial) compared with elastic (carotid) arteries. Resistance is only increased at the temporal artery vascular bed, suggesting cranioselectivity for resistance vessels. Endothelial function is not differently affected by any of the triptans tested. (Clin Pharmacol Ther 2000;68:418-26.) Clinical Pharmacology & Therapeutics (2000) 68, 418–426; doi: 10.1067/mcp.2000.110502

This study is altogether an extended legend for the folded maps incorporated in this volume, a review of the current knowledge on the Oman-United Arab Emirates ophiolite belt, and a new synthesis at the scale of the entire belt. Following a brief description of the petrological and structural units composing the ophiolite, the content of the three structural maps (planar structures, linear structures and dikes) is presented. Next, we discuss the various constraints introduced by these data in view of a synthesis of the ophiolite belt in terms of an ocean floor spreading system. Because they are the link between the factual results summarised in the maps, and the ridge models, these constraints are critical (and are central to the structural analysis of ophiolites). They introduce severe limits to possible ridge models such as those proposed in the conclusion. After being reassembled in a best geometrical and structural fit, the belt is parted into three domains (Figure 1). The south-eastern and central domains (from Wadi Tayin to Haylayn and possibly Sarami massifs) incorporate a 40–50 km-wide and possibly over 200 km long new ridge segment, oriented NW–SE, which is opening into a 1–2 My older lithosphere oriented NE–SW. The northern domain (from Khawr Fakkan to Hilti massifs) is well explained by a model of propagating (Aswad) and failing (Fizh) ridge segments of nearly parallel NNW-SSE orientation which are separated by a 10–20 km-wide transform zone covering the north of Fizh massif. This new synthesis integrates and updates the local syntheses published so far. It illustrates again the contrast between locally simple ridge segments organised around mantle diapirs and the tectonic complexity of the two larger domains, with, as an example, sheared mantle, vertical Moho and dismembered lower crust with hydrous contamination, near the tip of ridge propagators. The relation between the northern and central-southern domains is obscure because the paleomagnetic results suggest that, with respect to the central-southern domain, the northern domain should have rotated 130° clockwise. Such a large rotation of a 200 km long domain is difficult to explain, inasmuch as the age constraints seem to restrict the possible duration of the rotation to a couple of Myr. The preferred model consists in a progressive clockwise rotation during tectonic accretion of increasingly larger blocks. This is initiated in the northern massifs, progressing over 1–2 Myr, southward to finally integrate the entire ophiolite.

Mafic dikes and dunite veins are observed in the mantle section of the Oman ‐ United Arab Emirates (O-UAE) ophiolites, as well as diabase dikes and hydrothermal veins in the crust section. They have been systematically measured during the mapping of this ophiolite and are represented by their trajectories in the folded map 3 in the back of this volume, and by local stereoplots included in this study. Mafic dikes in the mantle section correspond to basaltic melt being injected at decreasing temperatures from above or at peridotite solidus, down to below 450C. Hydrothermal veins associated with dioritic dikes issued from hydrous melting of host gabbros are observed down to the base of the crust, bearing evidence for sea water penetration into basal gabbros at or above 900C, that is very close to the ridge axis. Dike orientations record the stress field at the time of their injection. In most places, all types of dikes are dominantly parallel to the general trend of the nearest sheeted dike complex; thus the stress field has not visibly changed from melt injection in the asthenosphere below the ridge of origin to injection in a lithosphere up to a few Myr old, at distances beyond 100 km from the axis. Local preferred orientations, when they are considered in the frame of the paleo-ridge system of O-UAE, result in a coherent model throughout the belt: the sheeted dike complex dips moderately away from the presumed ridge axis and the mantle dikes, toward this axis. These opposite directions are explained by the presumed effect of subsidence toward the axis for the sheeted dikes and by the central feeding from an asthenospheric uprise for the mantle dikes.

Renal 11beta-hydroxysteroid dehydrogenases (11beta-HSDs) are subject to modulation by various endogenous factors. 11beta-HSDs convert glucocorticoids into inactive 11-ketones and thereby determine tissue levels of active glucocorticoids and thus the extent of glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) activation. As such, modulation of the activity of renal 11beta-HSDs may contribute to the cascade of regulatory events involved in renal electrolyte water handling. We investigated whether renal 11beta-HSDs are modulated by elevated circulating angiotensin II. In rats infused for 2 wk with angiotensin II (250 ng/[kg x min] subcutaneously), plasma angiotensin II, aldosterone, and corticosterone were raised 5.1-, 10.7-, and 2.3-fold, respectively, compared with control rats. Angiotensin II infusion raised corticosterone 11beta-oxidation 1.46- and 1.35-fold in renal cortical proximal and distal tubules (enriched by Percoll centrifugation), respectively, but had no effect on 11beta-HSD1 and 11beta-HSD2 mRNA levels (semiquantitative reverse transcriptase polymerase chain reaction), except for distal tubular 11beta-HSD1 mRNA, which was decreased to 50%. In vitro treatment of freshly isolated tubules with angiotensin II for 45 min prior to assessment of 11beta-HSD activity showed no direct acute effects of angiotensin II on tubular corticosterone 11beta-oxidation. The enhanced renal tubular corticosterone 11beta-oxidation in vivo may partly protect renal GR and MR from elevated plasma corticosterone on angiotensin II infusion.

The eastern end of the Haylayn massif exposes a complex paleoridge structure interpreted as the tip of a northwestward propagating segment (Nicolas et al., this issue). The area, revisited from a petrostructural and geochemical viewpoint, offers the most documented exposures of the association of olivine gabbros and gabbronorites in Oman (Juteau et al., 1988). Gabbronorites were injected while the main gabbro unit was deforming in the magmatic state. Both units do not differ chemically, except for the SiO2 enrichment of the orthopyroxene-rich gabbros relative to olivine-gabbro. In addition, they display the same trace element signature, which implies the same parent magma for both units. The extension of the stability field of orthopyroxene is assigned to increase of oxygen fugacity due to hydration. The source of hydration is the ridge axis hydrothermal circulation, suggesting hydrothermal/magma interaction at temperatures above the gabbro solidus. The distribution of gabbronorites at the scale of the entire ophiolite suggests a relation with ridge tectonics where high-T conditions of hydrothermal-magmatic interaction are met. Such conditions are met when propagating segments rotate the structures of the dying magma chamber.

Rats are generally believed to be insensitive for cardiac glycosides. However, like in humans, the hemodynamic effects may be related to the pathophysiological condition. Since the hemodynamic effects of cardiac glycosides have never been investigated in rats with heart failure, the aim of the present experiments was to investigate the role of the pathophysiological condition in the rat. Therefore, hemodynamic and cardiac effects of ouabain were investigated both in normal rats and rats with heart failure due to myocardial infarction (MI). Since the effects of ouabain may also depend on the treatment scheme, rats were treated either for a short-term period or a long-term period. Three weeks after sham surgery or ligation of the left coronary artery (MI), Wistar rats were treated for two weeks with ouabain (14.4 mg/kg.d s.c.), either continuously (osmotic minipumps) or intermittently (once daily). A separate group of rats was treated for 45-60 min (1-100 microg/kg.min ouabain; i.v. infusion 5 weeks after MI). Hemodynamic measurements were performed at rest and after volume loading in conscious rats, chronically instrumented with an electromagnetic flow probe and catheters. Induction of MI resulted in a significant increase in total peripheral resistance (TPR), and a significant decrease in basal and maximal cardiac output following volume loading (basal CO: sham, 92 +/- 5; MI, 74 +/- 5 ml/min; maximal CO: sham, 152 +/- 4; MI, 105 +/- 7 ml/min; n = 7-11). Chronic intermittent ouabain treatment further increased TPR in MI rats. In contrast, continuous ouabain treatment normalized TPR in rats. Only in continuously treated MI rats, basal and maximal CO improved significantly (basal: 83 +/- 4; maximal: 134 +/- 7 ml/min; n = 7). Acute treatment dose-dependently worsened the hemodynamic conditions of MI rats, since TPR and MAP increased and CO and stroke volume decreased significantly. These experiments demonstrate that ouabain can improve cardiac function in rats, although only in MI rats and strongly depending on the delivery regimen. Thus, in contrast to the general belief, the presently used rat model is suitable for investigation of cardiac glycosides in heart failure. The preferential improvement of cardiac function in MI rats continuously treated with ouabain may depend upon changes in Na+,K+-ATPase or altered neurohumoral conditions due to MI and chronic treatment.