Protracted Respiratory Failure in a Case of Global Spinal Syringomyelia and Chiari Malformation Following Administration of Diazepam: Illustrative Case

BACKGROUND: Syringomyelia is defined as dilation of the spinal cord\u27s central canal and is often precipitated by skull base herniation disorders. Although respiratory failure (RF) can be associated with skull base abnormalities due to brainstem compression, most cases occur in pediatric patients and quickly resolve. The authors report the case of an adult patient with global spinal syringomyelia and Chiari malformation who developed refractory RF after routine administration of diazepam. OBSERVATIONS: A 31-year-old female presented with malnutrition, a 1-month history of right-sided weakness, and normal respiratory dynamics. After administration of diazepam prior to magnetic resonance imaging (MRI), she suddenly developed hypercapnic RF followed MRI and required intubation. MRI disclosed a Chiari malformation type I and syrinx extending from C1 to the conus medullaris. After decompressive surgery, her respiratory function progressively returned to baseline status, although 22 months after initial benzodiazepine administration, the patient continues to require nocturnal ventilation. LESSONS: Administration of central nervous system depressants should be closely monitored in patients with extensive syrinx formation given the potential to exacerbate diminished central respiratory drive. Early identification of syrinx in the context of Chiari malformation and hemiplegia should prompt clinical suspicion of underlying respiratory compromise and early involvement of intensive care consultants

Seismicity of the Atlantis Massif detachment fault, 30°N at the Mid-Atlantic Ridge

Author Posting. © American Geophysical Union, 2012. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 13 (2012): Q0AG11, doi:10.1029/2012GC004210.At the oceanic core complex that forms the Atlantis Massif at 30°N on the Mid-Atlantic Ridge, slip along the detachment fault for the last 1.5–2 Ma has brought lower crust and mantle rocks to the seafloor. Hydroacoustic data collected between 1999 and 2003 suggest that seismicity occurred near the top of the Massif, mostly on the southeastern section, while detected seismicity along the adjacent ridge axis was sparse. In 2005, five short-period ocean bottom seismographs (OBS) were deployed on and around the Massif as a pilot experiment to help constrain the distribution of seismicity in this region. Analysis of six months of OBS data indicates that, in contrast to the results of the earlier hydroacoustic study, the vast majority of the seismicity is located within the axial valley. During the OBS deployment, and within the array, seismicity was primarily composed of a relatively constant background rate and two large aftershock sequences that included 5 teleseismic events with magnitudes between 4.0 and 4.5. The aftershock sequences were located on the western side of the axial valley adjacent to the Atlantis Massif and close to the ridge-transform intersection. They follow Omori's law, and constitute more than half of the detected earthquakes. The OBS data also indicate a low but persistent level of seismicity associated with active faulting within the Atlantis Massif in the same region as the hydroacoustically detected seismicity. Within the Massif, the data indicate a north-south striking normal fault, and a left-lateral, strike-slip fault near a prominent, transform-parallel, north-facing scarp. Both features could be explained by changes in the stress field at the inside corner associated with weak coupling on the Atlantis transform. Alternatively, the normal faulting within the Massif might indicate deformation of the detachment surface as it rolls over to near horizontal from an initial dip of about 60° beneath the axis, and the strike-slip events may indicate transform-parallel movement on adjacent detachment surfaces.We thank the Deep Ocean Exploration Institute at WHOI, Director of Research at WHOI, WHOI’s Department of Geology and Geophysics, and the National Science Foundation for funding the data collection.2013-04-0

Cannabinoid receptor-interacting protein Crip1a modulates CB1 receptor signaling in mouse hippocampus

The online version of this article (doi:10.1007/s00429-015-1027-6) contains supplementary material, which is available to authorized users.This work was supported by the Deutsche Forschungsgemeinschaft FOR926 (subprojects SP3 to B. L. and K. M.), SFB 1080 (subprojects A1 to H. J. L. and B8 to B. L.), the Australian Research Council (ARC Future Fellowship to M. K.), the Hungarian Brain Research Program, KTIA_NAP_13-2-2014-0013 (to A.A.), the Swedish Medical Research Council and the Novo Nordisk Foundation (T. H.

Landmark Recognition in Alzheimer’s Dementia: Spared Implicit Memory for Objects Relevant for Navigation

Contains fulltext : 97074.pdf (publisher's version ) (Open Access)BACKGROUND: In spatial navigation, landmark recognition is crucial. Specifically, memory for objects placed at decision points on a route is relevant. Previous fMRI research in healthy adults showed higher medial-temporal lobe (MTL) activation for objects placed at decision points compared to non-decision points, even at an implicit level. Since there is evidence that implicit learning is intact in amnesic patients, the current study examined memory for objects relevant for navigation in patients with Alzheimer's dementia (AD). METHODOLOGY/PRINCIPAL FINDINGS: 21 AD patients participated with MTL atrophy assessed on MRI (mean MMSE = 21.2, SD = 4.0), as well as 20 age- and education-matched non-demented controls. All participants watched a 5-min video showing a route through a virtual museum with 20 objects placed at intersections (decision points) and 20 at simple turns (non-decision points). The instruction was to pay attention to the toys (half of the objects) for which they were supposedly tested later. Subsequently, a recognition test followed with the 40 previously presented objects among 40 distracter items (both toys and non-toys). Results showed a better performance for the non-toy objects placed at decision points than non-decision points, both for AD patients and controls. CONCLUSION/SIGNIFICANCE: Our findings indicate that AD patients with MTL damage have implicit memory for object information relevant for navigation. No decision point effect was found for the attended items. Possibly, focusing attention on the items occurred at the cost of the context information in AD, whereas the controls performed at an optimal level due to intact memory function.5 p

Long-range temporal correlations in the EEG bursts of human preterm babies.

The electrical activity in the very early human preterm brain, as recorded by scalp EEG, is mostly discontinuous and has bursts of high-frequency oscillatory activity nested within slow-wave depolarisations of high amplitude. The temporal organisation of the occurrence of these EEG bursts has not been previously investigated. We analysed the distribution of the EEG bursts in 11 very preterm (23-30 weeks gestational age) human babies through two estimates of the Hurst exponent. We found long-range temporal correlations (LRTCs) in the occurrence of these EEG bursts demonstrating that even in the very immature human brain, when the cerebral cortical structure is far from fully developed, there is non-trivial temporal structuring of electrical activity