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Pre-mature birth impacts left ventricular development, predisposing this population to long-term cardiovascular risk. The aims of this study were to investigate maturational changes in rotational properties from the neonatal period through 1 year of age and to discern the impact of cardiopulmonary complications of pre-maturity on these measures.
Pre-term infants (<29 weeks at birth, n = 117) were prospectively enrolled and followed to 1-year corrected age. Left ventricular basal and apical rotation, twist, and torsion were measured by two-dimensional speckle-tracking echocardiography and analysed at 32 and 36 weeks post-menstrual age and 1-year corrected age. A mixed random effects model with repeated measures analysis was used to compare rotational mechanics over time. Torsion was compared in infants with and without complications of cardiopulmonary diseases of pre-maturity, specifically bronchopulmonary dysplasia, pulmonary hypertension, and patent ductus arteriosus.
Torsion decreased from 32 weeks post-menstrual age to 1-year corrected age in all pre-term infants (p < 0.001). The decline from 32 to 36 weeks post-menstrual age was more pronounced in infants with cardiopulmonary complications, but was similar to healthy pre-term infants from 36 weeks post-menstrual age to 1-year corrected age. The decline was due to directional and magnitude changes in apical rotation over time (p < 0.05).
This study tracks maturational patterns of rotational mechanics in pre-term infants and reveals torsion declines from the neonatal period through 1 year. Cardiopulmonary diseases of pre-maturity may negatively impact rotational mechanics during the neonatal period, but the myocardium recovers by 1-year corrected age.
Attention is hypothesized to increase the brain's functional connectivity measured as EEG coherence between brain areas. Is this true for different types of attention compared to no-task resting?
In 25 healthy, meditation-naïve, right-handed, male students 58-channel EEG was recorded during three conditions of 5 minutes each with closed eyes in randomized order: (1) resting [3 runs], (2) mental arithmetic [2 runs], and (3) breath counting, a meditation initiation technique [2 runs]. For the 8 EEG frequency bands, the artifacted EEG was recomputed into sLORETA intracerebral current densities. To avoid localization ambiguities, we computed EEG coherence between sLORETA areas. To avoid effects of volume conduction, we computed intracerebral `lagged coherence' connectivity between sLORETA current densities in 19 areas. Averaged resting runs were compared to those breath counting and arithmetic runs of which participants post-hoc reported that their concentration was best.
Paired t-tests between conditions yielded differences of coherence at p< 0.1 (corrected for multiple testing) for 5 EEG frequency bands (delta, theta, alpha1, alpha2, beta3) [number of connections in brackets]: coherence was lower in breath counting than arithmetic (delta, beta3 [1,1]). Coherence was lower in resting than arithmetic (alpha2 ), but higher in resting than breath counting (theta, alpha1, alpha2, beta3 [2,1,1,1]).
Attention to breath counting showed lowest, to arithmetic highest demands on intracerebral functional connectivity. Breath counting and mental arithmetic induce mental states whose inter-area connectivity differs in opposite directions from resting. The results do not support a global hypothesis of increased coherence during attention.
The measure of complex dimensionality assesses the number of independent processes that generate an observed time series.
To investigate whether meditation exercises are associated with fewer or more independently active brain processes, and whether different meditation traditions show different results.
Does brain electric complex dimensionality differ between the state of meditation and of task free resting in different meditation traditions?
Multichannel EEG recordings (19 to 25 channels) from experienced meditators of five meditation traditions (13 Tibetan Buddhists, 15 Qigong, 14 Shaja Yoga, 14 Ananda Marga Yoga, and 15 Zen) were analyzed (bandpass 1.5–30 Hz) using ‘Omega Complexity’ that obtains a single value for a set of simultaneously recorded EEG time series from a given person (J. Wackermann, Acta Neurobiol Exp (Wars) 1996;56:197–208). Omega Complexity during meditation was compared to the mean of Omega Complexity during pre- and post-meditation resting.
During meditation relative to resting (paired t tests), Omega Complexity was higher in all five traditions, significant for Tibetan Buddhists (p = 0.01), Ananda Marga Yoga (p = 0.007) and Zen (p = 0.0003).
The subjectively experienced agreeable feelings during meditation apparently occur, across meditation traditions, during a brain functional state that is characterized by an increase of independent brain processes compared to task free resting.
Different meditation practices reportedly affect brain electric activity.
To assess common characteristics in brain electric activity during the state of meditation across different meditation traditions.
Do meditation traditions share commonalities in EEG spectral power changes from task-free resting to meditation?
Data from 71 experienced meditators of five meditation traditions were analyzed (13 Tibetan Buddhists, 15 Qigong, 14 Shaja Yoga, 14 Ananda Marga Yoga, and 15 Zen). Power spectral results of multichannel EEG recordings (average reference) during meditation were compared with those during pre- and post-meditation task-free resting. Spectra were averaged across channels (19–58), and subject-wise normalized. Integrated power was computed for the eight independent frequency bands (delta through gamma).
During meditation compared to the average of pre- and post-meditation resting, across the five traditions, there was a significant decrease of power in the alpha-2 band (10.5–12 Hz), and significant increases of power in the beta-3 (21.5–30 Hz) and gamma (35–44 Hz) bands; theta (6.5–8 Hz) band power showed an increase at p = 0.14.
The results indicate that EEG spectral power differences between task-free resting state EEG versus meditation state EEG show communalities that are shared by all five meditation traditions in spite of important differences in meditation techniques.
Arithmetic reportedly involves left parietal areas.
To test this in independent groups of healthy persons.
Which brain regions are activated / inhibited during mental arithmetic compared to task-free resting?
We examined four independent groups of healthy adults (N = 15, 14, 14, 23, respectively) during simple arithmetic (continuous subtraction of 7) and task-free resting before and after arithmetic, all with closed eyes. Multichannel head surface EEG (19–58 channels) was continually recorded, then recomputed (using sLORETA functional tomography) into current density for 6239 cortical voxels, for each of the eight EEG frequency bands (delta through gamma, 1.5–44 Hz). Pre- and post-arithmetic resting was averaged. Using paired t-tests, frequency band-wise normalized and log-transformed current density was compared between arithmetic and resting for each group. The resulting p-values were combined across groups using Fisher’s combination procedure. For each frequency band, sLORETA voxels differing between conditions at Fisher’s (across groups) p < 0.05 were computed into centers of gravity separately for increased and decreased activation.
Activity that was stronger during arithmetic compared to resting had gravity centers in midline anterior regions for slow frequency bands (delta, theta, alpha-1) and in right posterior regions for fast frequency bands (alpha-2 through gamma). Activity that was weaker during arithmetic compared to resting was centered around left parietal areas for all eight frequency bands.
The results suggest that arithmetic compared to resting involves frontal inhibition coupled with increased right parietal activation, and left parietal reduced facilitatory and reduced inhibitory activity.
Functional network disruption in degenerative dementia has been reported. EEG coherence is used to assess functional connectivity between brain areas. Previous studies of Huntington's disease (HD) reported about electroencephalography (EEG) spectral power and source location, but coherence has not yet been examined.
Objectives and Aims
To examine EEG intracortical functional connectivity in HD using low-resolution brain electromagnetic tomography (LORETA).
In 55 HD patients and 55 controls, 3-minute 19-channel vigilance-controlled EEG was recorded, and recomputed to current densities of 6239 cortical sLORETA voxels. These were recomputed into source model time series for 19 regions of interest (ROIs). Coherence overestimation due to volume conduction was avoided by computing functional connectivity as ‘lagged’ coherence. This was done for each ROI pair (19*18/2=171) in each of 8 EEG frequency bands (delta through gamma). Statistics tested coherences (a) HD patients versus controls, and (b) HD patients in early versus late disease stages.
(a) HD patients showed only reduced connectivities compared to controls (p < 0.05 corrected for multiple comparison), involving EEG theta, alpha-1-2 and beta1-2-3 frequency bands. The largest number of reduced connectivities occurred in alpha-1 (79 cases) and beta-2 (96 cases). (b) HD stage-1 versus stage-3-4 revealed only one significant difference.
HD compared to controls showed massive reduction of functional connectivity. This occurred early and remained stable during disease progression. As in other dementing disorders, for example Alzheimer disease, the largest reduction concerned alpha and beta EEG frequencies. The results suggest a neocortical disconnection syndrome of a primarily subcortical disease.
Vertigo and anxiety are frequent symptoms in both psychiatric and vertigo patients, especially in those with phobic postural vertigo (PPV). The aim of this study was the investigation of anxiety-associated functional responses in PPV patients compared to healthy controls. For that purpose cholecystokinin tetrapeptide (CCK-4), a valid model to experimentally induce anxiety symptoms, was used.
15 PPV patients and 15 matched healthy controls underwent challenges with CCK-4. During the paradigm, participants did not know the exact time point of the injection in order to separate the anticipatory and CCK-4 induced anxiety. The panic symptom scale score was assessed before and after the injection.
During anticipatory anxiety healthy controls showed functional responses mainly in fronto-temporal regions. Patients suffering from PPV showed pronounced BOLD responses in the (ventral) anterior cingulate cortex (ACC), dorsolateral prefrontal cortex, orbitofrontal cortex and precuneus. In healthy subjects, CCK-4 induced anxiety was accompanied by activations in the medial and inferior frontal cortex. In PPV, the CCK-4 injection led to increased activities particularly in the ACC, the cuneus, the cerebellum, the amygdala and fronto-temporal regions.
Given the fact of increased neuronal responses in emotion-related brain areas in patients with anxiety disorders these findings could provide evidence for common aspects of phobic postural vertigo and anxiety disorders.
Measles, mumps, rubella (MMR) and varicella zoster virus (VZV) infection can cause serious diseases and complications in the HIV-positive population. Due to successful vaccination programmes measles, mumps and congenital rubella syndrome has become neglected in Germany. However, recent outbreaks of measles have occurred from import-associated cases. In this cross-sectional study the serostatus for MMR and VZV in 2013 HIV-positive adults from three different university outpatient clinics in Bonn (n = 544), Cologne (n = 995) and Munich (n = 474) was analysed. Sera were tested for MMR- and VZV-specific immunglobulin G antibodies using commercial immunoassays. Seronegativity was found in 3% for measles, 26% for mumps, 11% for rubella and 2% for VZV. Regarding MMR, 35% of patients lacked seropositivity against at least one infectious agent. In multivariable analysis younger age was strongly associated with seronegativity against all four viruses, measles, mumps, rubella (P < 0·001, P < 0·001 and P = 0·001, respectively) and VZV (P = 0·001). In conclusion, there is high need for MMR and VZV vaccination in people living with HIV in Germany born in 1970 or later. Thus, systematic MMR and VZV antibody screening and vaccination should be implemented in the HIV-positive population to prevent serious disease and complications of vaccine-preventable diseases.
As part of the activities of the Collaborative Research Centre ‘SFB 350’, measurements of geodetic and geodynamic changes in the area of the Lower Rhine Embayment and the Rhenish Shield are being performed at different scales in space and time. Continuous borehole tilt measurements and repeated microgravimetric surveys yield information on the local stability of the ground and changes in horizontal gravity gradients that are both dominated by seasonal fluctuations. Results of more than seven years of regular GPS campaigns are discussed in terms of vertical and horizontal point motions. The most prominent motions are man-induced effects occurring in or near the browncoal mining areas, where groundwater withdrawal produces subsidence of up to 2.2 cm/y in the area under investigation. Horizontal and vertical motions at other GPS points are smaller by one order of magnitude and in most cases are only marginally detectable. The eastward motion of two points in the Bergisches Land and the westward motion of two points in the Eifel near the Belgian border may be interpreted as a result of the ongoing extension of the Cenozoic rift system in the western part of the Eurasian plate.
Our investigations with silane-modified TiO2 have revealed a beneficial effect of functionalization on the photoelectrochemical performance on spin-coated electrodes. However, in order to produce large area photoelectrodes, a more scalable manufacturing technology is required. Inkjet printing can fulfil this role and furthermore allow a finer control over coating morphologies. In this work, inkjet-printed photoelectrodes were prepared with silane-functionalized TiO2 nanoparticles, and investigated as electrodes for photoactivated water splitting. The catalyst layers, having thickness around 700 nm, were printed on FTO-coated glass supports, from cellulose stabilized dispersions. For comparison, electrodes of similar thicknesses were also prepared by spin-coating. After removing the stabilizer at 300 °C under air atmosphere, the electrodes were characterized in photoelectrochemical cells containing 0.5 M H2SO4 as electrolyte and a platinum ring as counter electrode. Under simulated sunlight, the best photocurrent densities for the oxygen evolution reaction were obtained for the inkjet-printed electrodes prepared with functionalized particles (up to 0.26 mA cm-2 at 1.2 V against the standard hydrogen electrode (SHE), compared to 0.18 mA cm-2 for spin coated). Microscopy of the printed electrodes shows structurally homogenous coatings with evenly distributed roughness. Under continuous illumination at 0.7 V (SHE), the electrodes showed no significant drop in photocurrent within five hours.
We carried out an extensive photometric and spectroscopic investigation of the SPB binary, HD 25558 (see Fig. 1 for the time and geographic distribution of the observations). The ~2000 spectra obtained at 13 observatories during 5 observing seasons, the ground-based multi-colour light curves and the photometric data from the MOST satellite revealed that this object is a double-lined spectroscopic binary with a very long orbital period of about 9 years. We determined the physical parameters of the components, and have found that both lie within the SPB instability strip. Accordingly, both components show line-profile variations consistent with stellar pulsations. Altogether, 11 independent frequencies and one harmonic frequency were identified in the data. The observational data do not allow the inference of a reliable orbital solution, thus, disentangling cannot be performed on the spectra. Since the lines of the two components are never completely separated, the analysis is very complicated. Nevertheless, pixel-by-pixel variability analysis of the cross-correlated line profiles was successful, and we were able to attribute all the frequencies to the primary or secondary component. Spectroscopic and photometric mode-identification was also performed for several of these frequencies of both binary components. The spectroscopic mode-identification results suggest that the inclination and rotation of the two components are rather different. While the primary is a slow rotator with ~6 d rotation period, seen at ~60° inclination, the secondary rotates fast with ~1.2 d rotation period, and is seen at ~20° inclination. Our spectropolarimetric measurements revealed that the secondary component has a magnetic field with at least a few hundred Gauss strength, while no magnetic field was detected in the primary.
The detailed analysis and results of this study will be published elsewhere.
To evaluate an internet-based preapproval antimicrobial stewardship program for sustained reduction in antimicrobial prescribing and resulting cost savings.
Retrospective cohort study and cost analysis.
Review of all doses and charges of antimicrobials dispensed to patients over 6 years (July 1, 2005–June 30, 2011) at a tertiary care pediatric hospital.
Restricted antimicrobials account for 26% of total doses but 81% of total antimicrobial charges. Winter months (November–February) and the oncology and infant and toddler units were associated with the highest antimicrobial charges. Five restricted drugs accounted for the majority (54%) of charges but only 6% of doses. With an average approval rate of 91.5% (95% confidence interval [CI], 91.1%–91.9%), the preapproval antibiotic stewardship program saved $103,787 (95% CI, $98,583–$109,172) per year, or $14,156 (95% CI, $13,446–$14,890) per 1,000 patient-days.
A preapproval antimicrobial stewardship program effectively reduces the number of doses and subsequent charges due to restricted antimicrobials years after implementation. Hospitals with reduced resources for implementing postprescription review may benefit from a preapproval antimicrobial stewardship program. Targeting specific units, drugs, and seasons may optimize preapproval programs for additional cost savings.
Leptin is thought to act as an important mediator in stress reactions. To date, no study has examined the association between psychological stress and leptin levels in children. This study aimed to assess the association between emotional symptoms and peer problems and serum leptin levels in children aged 10 years of the two population-based GINI-plus and LISA-plus birth cohorts.
Cross-sectional data from 2827 children aged 10 years were assessed with regard to leptin concentrations in serum and behavioral problems using the parent-reported Strengths and Difficulties Questionnaire (SDQ). Linear regression modeling was applied to determine the likelihood of elevated leptin levels in children with emotional symptoms and peer problems, controlling for socio-economic status (SES), body mass index (BMI), fasting serum leptin levels, pubertal development and sex hormones.
We found that increases in emotional symptoms (exp βadj = 1.03, s.e. = 0.02, p < 0.04) and peer problems (exp βadj = 1.05, s.e. = 0.01, p = 0.0001) were significantly associated with higher serum leptin levels controlled for BMI and sociodemographic factors. Similar results were found when the fasting serum leptin sample was examined (exp βadj = 1.08, s.e. = 0.04, p = 0.0294). Gender-stratified analyses showed a significant relationship between serum leptin and peer problems in girls (exp βadj = 1.05, s.e. = 0.02, p = 0.03), and a borderline significant association in boys (exp βadj = 1.04, s.e. = 0.02, p = 0.05).
Children with peer problems have higher stress and eat more, acquire a higher body fat mass and thus, through increased leptin resistance, exhibit higher leptin levels.
We present the analysis of HD 181068 which is one of the first triply eclipsing triple system discovered. Using Kepler photometry, ground based spectroscopic and interferometric measurements, we determined the stellar and orbital parameters of the system. We show that the oscillations observed in the red giant component of the system are tidally forced oscillations, while one of the most surprising results is that it does not show solar-like oscillations.