T179. DO INDIVIDUALS IN A CLINICAL HIGH-RISK STATE FOR PSYCHOSIS DIFFER FROM HEALTHY CONTROLS IN THEIR CORTICAL FOLDING PATTERNS?

Background Volumetric brain differences between persons meeting criteria for a clinical high-risk state for psychosis (CHR) and healthy controls (HC) have been previously reported, yet little is known about potential abnormalities in surface-based morphological measures. Gyrification (i.e., the amount of cortical convolution) remains relatively stable across the lifespan and is minimally influenced by ubiquitous confounding factors (e.g., drug use, medication, or stress). Recently, a multi-site analysis conducted in 104 CHR persons found global increases in cortical gyrification compared to HC (Sasabayashi et al. 2017). If replicated, gyrification abnormalities in CHR could potentially serve as early neuromarkers of elevated risk, and thus could eventually be used to identify objectively and efficiently the CHR state. Methods A total of 124 CHR and 264 HC subjects were recruited as part of the PRONIA consortium (www.pronia.eu), a large-scale international longitudinal study currently consisting of 10 European sites. Cortical surfaces were reconstructed from structural MRI images using a volume-based, newly introduced technique called the Projection-Based-Thickness (PBT) as available in the SPM-based-toolbox CAT12. Local gyrification was quantified automatically across the whole brain as absolute mean curvature for each vertex of the brain surface mesh consisting of thousands of individual measurement points. Vertex-wise differences of curvature values were calculated applying a General Linear Model, corrected for age, gender and site effects. Results were investigated at corrected and uncorrected levels. Results We found no significant differences in vertex-wise gyrification between CHR and HC at either corrected or uncorrected levels (p>0.05). Further investigations of potential confounding site effects also did not reveal differences. Discussion Our preliminary findings suggest that CHR subjects do not show whole-brain gyrification abnormalities when compared with healthy subjects. These negative results agree with literature suggesting that cortical convolution might be more affected by neurodevelopmental or genetic factors, and thus deviations from normal patterns might not be detectable in heterogeneous samples of at-risk subjects wherein the etiology and ultimate prognosis is unknown. In order to better investigate differences in cortical folding and address the role of gyrification as neuroanatomical biomarker for psychosis, future investigations should focus on subgroups within CHR populations (e.g. patients groups defined by basic symptoms, ultra-high risk, or familial risk) in addition to specific analyses of individuals with higher neurodevelopmental (e.g., obstetric complications) or genetic (e.g., polygenic risk) loadings

Initial management of and outcome in patients with pneumococcal bacteremia: a retrospective study at a Swiss university hospital, 2003-2009

Purpose: The aim of this quality control study was to assess the time to initial diagnostic procedures and the time to the first dose of antibiotics in patients with pneumococcal bacteremia, and to investigate whether the timeliness of these interventions influenced outcome. Methods: We retrospectively studied patient characteristics, chronological sequence of diagnostic and therapeutic steps, and the course of disease of all patients with pneumococcal bacteremia at a Swiss university hospital between 2003 and 2009, and we analyzed associations between these factors and the length of hospital stay (LOS) and mortality. Results: A total of 102 episodes of pneumococcal bacteremia in 98 patients were analyzed, of whom 15.7% died during hospitalization. The median time (interquartile range [IQR]) to the first antibiotic dose was 4.0 (2.0-5.9)h, and the median times (IQR]) to blood cultures, chest radiograph, lumbar puncture, and brain computed tomography (CT) scan or magnetic resonance imaging (MRI) were 1.4 (0.5-3.3), 2.5 (1.2-4.2), 4.2 (2.7-7.2), and 2.3 (0.6-6.2)h, respectively. The time to diagnostic procedures and therapy were not associated with LOS or death. Risk factors for death in the univariable analysis were: Charlson comorbidity index [odds ratio [OR] (95% confidence interval) per unit increase, 1.3 (1.1-1.6)], neutropenia [OR 10.1 (2.0-51.0)], human immunodeficiency virus (HIV) infection [OR 3.9 (1.1-13.8)], chronic respiratory disease [OR 4.4 (1.2-16.0)], chronic liver disease [OR 3.2 (1.0-9.7)], smoking [OR 3.8 (1.1-13.5)], injection drug use [OR 9.7 (1.5-63.7)], and antibiotic therapy within 6months before admission [OR 4.0 (1.3-12.5)]. The multivariable analysis revealed age >60years (P=0.048) and alcoholism (P=0.009) as risks for prolonged LOS. Conclusions: The outcome of pneumococcal bacteremia may be more influenced by patient characteristics than by minor differences in the timeliness of initial diagnostic and therapeutic measures within the first several hours after hospital admissio

Rapidly Destructive Staphylococcus epidermidis Endocarditis

Abstract : A 29-year-old man with rapidly destructive Staphylococcus epidermidis endocarditis after mitral valve reconstruction is presented. Resistance to rifampin and teicoplanin occurred during antibiotic treatment resulting in clinical failure and valve destruction. Subsequently, the patient was successfully treated, by combining valve replacement with antibiotic therapy including quinupristin/dalfopristin, levofloxacin, and vancomycin. In conclusion, S. epidermidis can cause rapid valve destruction with large vegetations, and combination of surgery and antibiotic therapy may be necessar

Quantitative Antibiotic Use in Hospitals: Comparison of Measurements, Literature Review, and Recommendations for a Standard of Reporting

Abstract : Background: : Reports on antibiotic use often lack complete definitions of the units of measurement, hampering the comparison of data between hospitals or hospital units. Patients and Methods: : To compare methods of measures of in-hospital antimicrobial use, we determined aggregate in-hospital consumption data at a tertiary care university hospital using variations of nominators and denominators. Means of defined daily doses (DDD) of individual antimicrobials per 100 bed-days and per 100 admissions at each hospital and intensive care unit (ICU) were calculated. Furthermore, a literature review was performed for benchmarking purposes. Results: : Antibiotic use in different hospital units ranged from 0.105 to 323.37 DDD/100 bed-days and from 4.23 to 6737.92 DDD/100 admissions, respectively. Including the day of discharge in the denominator ‘bed-days' underestimated antibiotic use in various hospital wards by up to 27.7 DDD/100 bed-days (26.0%). Equating ‘numbers of patients admitted to the hospital' and ‘numbers of admissions' on a hospital level resulted in a difference of 192.6 DDD/100 admissions (64%) because patients transferred between hospital units accounted for multiple admissions. Likewise, reporting antimicrobial (Anatomical Therapeutic Chemical [ATC] group ‘J') instead of antibiotic (ATC group ‘J01') use led to a difference of 16.5 DDD/100 bed-days (19.3%). The literature review revealed underreporting of complete definitions of antibiotic use measurements. Conclusions: : Data on in-hospital antimicrobial use vary widely not only due to different antibiotic policies at different institutions but also due to different methods of measures. Adherence to the standard of reporting the methods of measurement is warranted for benchmarking and promotion of rational antimicrobial us

Networks of myelin covariance.

Networks of anatomical covariance have been widely used to study connectivity patterns in both normal and pathological brains based on the concurrent changes of morphometric measures (i.e., cortical thickness) between brain structures across subjects (Evans, ). However, the existence of networks of microstructural changes within brain tissue has been largely unexplored so far. In this article, we studied in vivo the concurrent myelination processes among brain anatomical structures that gathered together emerge to form nonrandom networks. We name these "networks of myelin covariance" (Myelin-Nets). The Myelin-Nets were built from quantitative Magnetization Transfer data-an in-vivo magnetic resonance imaging (MRI) marker of myelin content. The synchronicity of the variations in myelin content between anatomical regions was measured by computing the Pearson's correlation coefficient. We were especially interested in elucidating the effect of age on the topological organization of the Myelin-Nets. We therefore selected two age groups: Young-Age (20-31 years old) and Old-Age (60-71 years old) and a pool of participants from 48 to 87 years old for a Myelin-Nets aging trajectory study. We found that the topological organization of the Myelin-Nets is strongly shaped by aging processes. The global myelin correlation strength, between homologous regions and locally in different brain lobes, showed a significant dependence on age. Interestingly, we also showed that the aging process modulates the resilience of the Myelin-Nets to damage of principal network structures. In summary, this work sheds light on the organizational principles driving myelination and myelin degeneration in brain gray matter and how such patterns are modulated by aging

Neurobiological origin of spurious brain morphological changes: A quantitative MRI study.

The high gray-white matter contrast and spatial resolution provided by T1-weighted magnetic resonance imaging (MRI) has made it a widely used imaging protocol for computational anatomy studies of the brain. While the image intensity in T1-weighted images is predominantly driven by T1, other MRI parameters affect the image contrast, and hence brain morphological measures derived from the data. Because MRI parameters are correlates of different histological properties of brain tissue, this mixed contribution hampers the neurobiological interpretation of morphometry findings, an issue which remains largely ignored in the community. We acquired quantitative maps of the MRI parameters that determine signal intensities in T1-weighted images (R1 (=1/T1), R2 *, and PD) in a large cohort of healthy subjects (n = 120, aged 18-87 years). Synthetic T1-weighted images were calculated from these quantitative maps and used to extract morphometry features-gray matter volume and cortical thickness. We observed significant variations in morphometry measures obtained from synthetic images derived from different subsets of MRI parameters. We also detected a modulation of these variations by age. Our findings highlight the impact of microstructural properties of brain tissue-myelination, iron, and water content-on automated measures of brain morphology and show that microstructural tissue changes might lead to the detection of spurious morphological changes in computational anatomy studies. They motivate a review of previous morphological results obtained from standard anatomical MRI images and highlight the value of quantitative MRI data for the inference of microscopic tissue changes in the healthy and diseased brain. Hum Brain Mapp 37:1801-1815, 2016. © 2016 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc

Air suctioning during colon biopsy acquisition reduces bacterial contamination

Background and Aim: Contamination of endoscopy suites with bacteria during procedures is of concern particularly through droplets during handling of biopsy specimens. It has been advocated that suctioning while removing the biopsy forceps could help to reduce potentially hazardous bioaerosols. The aim of the present study was to evaluate the efficacy of air suctioning during removal of the biopsy forceps. Materials and Methods: Airborne bacteria were collected by an impactor air-sampler (MAS-100). Fifty liters of air were collected continuously for 30 seconds at a 30 cm distance from the colonoscope suction channel. Room air samples were taken in the endoscopy suite in the morning prior to the beginning of the endoscopy program, during colonoscopy with a sham biopsy in the descending colon with and without suctioning and at the end of the procedure day. Standard 90 mm Petri dishes containing a selective medium for gram-positive cocci (CNA blood agar) were used with the impaction sampler and colony forming units/m3 (cfu) were determined. Results: Measurements were performed at fifty consecutive colonoscopies. Prior to the beginning of the endoscopy program, the bioaerosol burden in the colonoscopy suite reached a mean of 4.2 cfu/m3. During colonoscopies performed without suctioning at biopsy the bioaerosol burden increased to 29.4 cfu/m3 whereas this burden increased only to 15.1 cfu/m3 when the suctioning was applied during removal of the biopsy forceps. The difference in bioaerosol burden between suctioning and no suctioning was highly significant (p < 0.0005). At the end of the procedure day the airborne bacteria count dropped to 15.6 cfu/m3. The analysis of the colonies on the CNA blood agar identified predominantly enterococci. Staphylococci spp. and other gram-positive bacteria were rarely isolated. Conclusion: The present study indicates that the bioaerosol burden during handling of biopsy specimens is not neglectable but can be reduced by the simple habit of applying suctioning during acquisition of biopsies. This practice might be an important infection-control measure during gastrointestinal endoscopies

Does Puget Sound have a long-term memory?

More than a decade of high-resolution, full-water column data collected by profiling UW ORCA/NANOOS moorings in several Puget Sound Basins are used to investigate interannual variability of near-surface and deep water properties. Although there are no significant trends in temperature, salinity, density and dissolved oxygen spanning the last decade, measurements show steady and relatively strong trends in these variables over periods of 3 to 5 years in both South Sound near bottom waters and in south Hood Canal deep water. For example, the annual minimum density in south Hood Canal deep water increased four years in a row from 2006 to 2009, then this trend reversed for three years. In Carr Inlet the annual maximum deep temperature increased five years in a row from 2011 to 2015, with deep salinity following a similar trend. As these trends are significantly longer than expected flushing and residence times (\u3c year), this hints at potential interannual dynamical feedbacks, longer-term system “memory”, and/or similar trends in ocean and atmospheric forcing. Using archived National Data Buoy Center, National Weather Service and UW Atmospheric Sciences data we explore and report on potential factors contributing to these trends

Magnetic resonance imaging correlates of first-episode psychosis in young adult male patients: combined analysis of grey and white matter.

Background: Several patterns of grey and white matter changes have been separately described in young adults with first-episode psychosis. Concomitant investigation of grey and white matter densities in patients with first-episode psychosis without other psychiatric comorbidities that include all relevant imaging markers could provide clues to the neurodevelopmental hypothesis in schizophrenia. Methods: We recruited patients with first-episode psychosis diagnosed according to the DSM-IV-TR and matched controls. All participants underwent magnetic resonance imaging (MRI). Voxel-based morphometry (VBM) analysis and mean diffusivity voxel-based analysis (VBA) were used for grey matter data. Fractional anisotropy and axial, radial and mean diffusivity were analyzed using tract-based spatial statistics (TBSS) for white matter data. Results: We included 15 patients and 16 controls. The mean diffusivity VBA showed significantly greater mean diffusivity in the first-episode psychosis than in the control group in the lingual gyrus bilaterally, the occipital fusiform gyrus bilaterally, the right lateral occipital gyrus and the right inferior temporal gyrus. Moreover, the TBSS analysis revealed a lower fractional anisotropy in the first-episode psychosis than in the control group in the genu of the corpus callosum, minor forceps, corticospinal tract, right superior longitudinal fasciculus, left middle cerebellar peduncle, left inferior longitudinal fasciculus and the posterior part of the fronto-occipital fasciculus. This analysis also revealed greater radial diffusivity in the first-episode psychosis than in the control group in the right corticospinal tract, right superior longitudinal fasciculus and left middle cerebellar peduncle. Limitations: The modest sample size and the absence of women in our series could limit the impact of our results. Conclusion: Our results highlight the structural vulnerability of grey matter in posterior areas of the brain among young adult male patients with first-episode psychosis. Moreover, the concomitant greater radial diffusivity within several regions already revealed by the fractional anisotropy analysis supports the idea of a late myelination in patients with first-episode psychosis