bluuebunny/crossref_metadata_2025_split huggingface dataset:
Visual Dysfunction and Computational Sleep Depth Changes in Obstructive Sleep Apnea Syndrome
Authors: Saunamäki Tiia , Jehkonen Mervi , Huupponen Eero , Polo Olli , Himanen Sari-Leena 
Published: February 2012

The aims of this study are to clarify whether patients with obstructive sleep apnea syndrome (OSAS) have a decline in verbally or visually-based cognitive abilities and whether the possible decline is related to particular sleep depth changes. In addition, the effect of continuous positive airway pressure (CPAP) on the possible changes is investigated. Fifteen OSAS patients and 15 healthy controls joined two full-night polysomnographies, including a computational measure of deep sleep percentage (DS%) bilaterally from the frontal, central and occipital channels, and a neuropsychological assessment. After a 6-month CPAP the patients underwent one more full-night polysomnography with computational DS% analysis and a neuropsychological assessment. At the baseline, the OSAS patients had poorer performance in the Picture Completion, in the Digit Symbol and in copying the Rey-Osterrieth Complex Figure Test (ROCFT) compared to the controls. The patients also showed reduced DS% in all 6 electrographic (EEG) channels compared to controls. The patients had an inter-hemispheric difference showing less deep sleep in the right hemisphere than in the left hemisphere both frontopolarly and centrally, while the controls showed this inter-hemispheric difference only frontopolarly. After CPAP the patients still had poorer performance in the Picture Completion and in the ROCFT. The patients continued to show reduced DS% in all 3 channels of the right hemisphere and occipitally in the left hemisphere, also the inter-hemispheric difference frontopolarly and centrally remained. OSAS patients have mild visually based cognitive dysfunction and reduced amount of deep sleep in the right hemisphere even after CPAP.
Utilization of Below-the-Hairline EEG in Detecting Subclinical Seizures
Authors: Bubrick Ellen J. , Bromfield Edward B. , Dworetzky Barbara A. 
Published: February 2012

Nonconvulsive status epilepticus (NCSE) is a serious condition commonly considered when evaluating a patient with altered mental status, and an electroencephalogram (EEG) is necessary for diagnosis. Neurology house staff often must make this diagnosis at times when no EEG technologist is available. We report our experience with abbreviated, emergency below-the-hairline EEGs (BTH-EEG) performed by neurology residents at our institution over a 1–1/2 year period. We analyzed demographic and clinical data in relation to whether or not an ictal or periodic pattern was identified, and these results were compared to follow up EEGs. Thirty-nine studies were identified, ranging in duration from 3 min-13 hrs. Mean and median age of patients included was 53 (range 25–81yrs); 21 were female. Seven of 39 BTH-EEGs showed at least one electrographic seizure, 9 more showed periodic discharges. Follow-up EEGs showed electrographic seizures in 6 of 39 patients, including 3 of the 7 with ictal BTH-EEG, and an additional 3 whose BTH-EEGs showed periodic lateralized discharges but no organized seizures. All 7 patients with ictal BTH-EEGs survived to discharge, vs. 23 of the remaining 32. We conclude that in selected cases, BTH-EEG is useful in detecting seizures and/or other epileptiform patterns. In our series, when NCSE was in question, the BTH-EEG showed these patterns 41% of the time. The BTH-EEG is a fast, non-invasive, inexpensive tool that may save valuable time, especially when no other viable option is immediately available. This technique may be applicable more broadly, not just limited to centers with neurology residents.
EEG Topography and Tomography (LORETA) in Diagnosis and Pharmacotherapy of Depression
Authors: Saletu B. , Anderer P. , Saletu-Zyhlarz G.M. 
Published: February 2012

Earlier investigations suggested an involvement of the right hemisphere and the left prefrontal cortex (PFC) in the pathogenesis of depression. This paper presents our own electroencephalographic (EEG) topography and low-resolution brain electromagnetic tomography (LORETA) data obtained in unmedicated depressed patients, and the effects of two representative drugs of non-sedative and sedative antidepressants, i.e., citalopram (CIT) and imipramine (IMI), as compared with placebo in normal subjects. Sixty female menopausal syndrome patients with the diagnosis of a depressive episode without psychotic symptoms as well as 30 healthy controls were investigated. Concerning the effects of antidepressants, normal healthy subjects received single oral doses of 20 mg CIT, 75 mg IMI and placebo p.o. A 3-min vigilance-controlled EEG and a 4-min resting EEG was recorded pre- and post-drug administration and analyzed by means of EEG mapping and LORETA. In the EEG mapping, depressed patients demonstrated a decrease in absolute power in all frequency bands, an augmentation of relative delta/theta and beta and a decrease in alpha activity as well as a slowing of the delta/theta centroid and an acceleration of the alpha and beta centroid, which suggests vigilance decrements. In the alpha asymmetry index, they showed right frontal hyper- and left frontal hypoactivation correlated with the Hamilton Depression Score (HAMD). LORETA predominantly revealed decreased power in the theta and alpha-1 frequency band. Negative correlations between theta power and the HAMD were observed in the ventro-medial PFC, the bilateral rostral anterior cingulate cortex (ACC) and the left insular cortex; between alpha-1 power and the HAMD in the right PFC. In the EEG mapping of antidepressants, 20 mg CIT showed mainly activating, 75 mg IMI partly sedative properties. LORETA revealed that CIT increased alpha-2, beta-1, beta-2 and beta-3 power more over the right than over the left hemisphere. However, also a left temporal and frontal delta increase was observed. In conclusion, EEG topography and tomography of depressed menopausal patients demonstrated a right frontal hyper- and left frontal hypoactivation in the alpha asymmetry index as well as a vigilance decrease, with a right-hemispheric preponderance. Within antidepressants at least 2 subtypes may be distinguished from the electrophysiological point of view, a non-sedative and a sedative. LORETA identifies cerebral generators responsible for the pathogenesis of depression as well as for the mode of action of antidepressants.
Low-Frequency Repetitive Transcranial Magnetic Stimulation for the Treatment of Refractory Partial Epilepsy
Authors: Sun Wei , Fu Wei , Mao Wei , Wang Dequan , Wang Yuping 
Published: February 2012

Seventeen refractory partial epilepsy patients were enrolled in an open-label study to evaluate the antiepileptic effect of low-frequency repetitive transcranial magnetic stimulation (rTMS). Seven of the patients had not obtained seizure-free status after epileptogenic focus resection surgery before they were enrolled in the study. All patients were treated with low-frequency rTMS which included 3 sessions per day (0.5 Hz, 90% RMT and 500 pulses each session) and lasted for 2 weeks. Seizure frequency, seizure days and epileptic discharges in the EEG obtained before, during and after stimulation were compared. The psychological conditions of all individual patients were evaluated with Symptom Checklist-90 (SCL-90) before and after rTMS treatment. Mean seizure frequencies per week significantly decreased in the following 4-week rTMS treatment period compared with the pretreatment period (14.09 vs. 5.63, p < 0.05, mean reduction of 60.02% in seizure frequency). Mean seizure days per week during the treatment period and the post-treatment period were lower than that of the pretreatment period (5.18 vs. 2.99 p < 0.05, mean reduction of 42.5% in seizure days). Mean epileptic discharges in the EEG decreased significantly during the treatment period compared to that of the pre-treatment period (78.60 vs. 66.09, p < 0.05, mean reduction of 15.9% in epileptic spikes discharges) in all 17 patients. Fourteen patients completed the test of Symptom Checklist-90 effectively. The scales of Global Severity Index, Depression, Anxiety, Phobic anxiety, Paranoid ideation, Psychoticism, Somatization, Obsession-compulsion, Interpersonal sensitivity, Hostility in patients decreased respectively at the post-treatment periods compared with those of the pre-treatment periods (P < 0.05). Low-frequency rTMS may have a significant antiepileptic effect in patients with refractory partial epilepsy. Additionally, our results indicate rTMS treatment can improve the psychological condition of these patients.
Bihemispheric Cerebral FDG PET Correlates of Cognitive Dysfunction as Assessed by the CERAD in Alzheimer's Disease
Authors: Schönknecht Oskar Dieter Peter , Hunt Aoife , Toro Pablo , Guenther Thomas , Henze Marcus , Haberkorn Uwe , Schröder Johannes 
Published: February 2012

Alzheimer's disease (AD) is characterized by a variety of cognitive deficits which can be reliably assessed by the neuropsychological test battery of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD), but the cerebral changes underlying the respective cognitive deficits are only partly understood. Measures of severity of dementia in AD as well as delayed episodic memory performance in mild cognitive impairment significantly correlated with bihemispheric cerebral glucose hypometabolism. We therefore hypothesized that the CERAD cognitive battery may represent cerebral dysfunction of both hemispheres in patients with AD. In 32 patients with AD, cerebral glucose metabolism was investigated using positron-emission-tomography with 18 Fluorodeoxyglucose (FDG PET) and associated with the test scores of the CERAD cognitive battery by statistical parametric mapping. Episodic memory scores significantly correlated with temporoparietal glucose metabolism of both hemispheres while delayed episodic memory significantly was correlated with the right frontotemporal cortices. Verbal fluency and naming scores significantly correlated with glucose metabolism in left temporoparietal and right frontal cortices, whereas constructional praxis predominantly correlated significantly with the bilateral precuneus. In conclusion, the results of our study demonstrate that not only memory function but also functions of language and constructional praxis in AD are associated with glucose metabolism as revealed by FDG PET in subsets of uni- and bilateral brain areas. The findings of our study for the first time demonstrate that in AD neuropsychological deficits as assessed by the CERAD refer to different cerebral sites of both hemispheres.
Simultaneous EEG/fMRI Analysis of the Resonance Phenomena in Steady-State Visual Evoked Responses
Authors: Bayram Ali , Bayraktaroglu Zubeyir , Karahan Esin , Erdogan Basri , Bilgic Basar , Özker Muge , Kasikci Itir , Duru Adil D. , Ademoglu Ahmet , Öztürk Cengizhan , Arikan Kemal , Tarhan Nevzat , Demiralp Tamer 
Published: February 2012

The stability of the steady-state visual evoked potentials (SSVEPs) across trials and subjects makes them a suitable tool for the investigation of the visual system. The reproducible pattern of the frequency characteristics of SSVEPs shows a global amplitude maximum around 10 Hz and additional local maxima around 20 and 40 Hz, which have been argued to represent resonant behavior of damped neuronal oscillators. Simultaneous electroencephalogram/functional magnetic resonance imaging (EEG/fMRI) measurement allows testing of the resonance hypothesis about the frequency-selective increases in SSVEP amplitudes in human subjects, because the total synaptic activity that is represented in the fMRI-Blood Oxygen Level Dependent (fMRI-BOLD) response would not increase but get synchronized at the resonance frequency. For this purpose, 40 healthy volunteers were visually stimulated with flickering light at systematically varying frequencies between 6 and 46 Hz, and the correlations between SSVEP amplitudes and the BOLD responses were computed. The SSVEP frequency characteristics of all subjects showed 3 frequency ranges with an amplitude maximum in each of them, which roughly correspond to alpha, beta and gamma bands of the EEG. The correlation maps between BOLD responses and SSVEP amplitude changes across the different stimulation frequencies within each frequency band showed no significant correlation in the alpha range, while significant correlations were obtained in the primary visual area for the beta and gamma bands. This non-linear relationship between the surface recorded SSVEP amplitudes and the BOLD responses of the visual cortex at stimulation frequencies around the alpha band supports the view that a resonance at the tuning frequency of the thalamo-cortical alpha oscillator in the visual system is responsible for the global amplitude maximum of the SSVEP around 10 Hz. Information gained from the SSVEP/fMRI analyses in the present study might be extrapolated to the EEG/fMRI analysis of the transient event-related potentials (ERPs) in terms of expecting more reliable and consistent correlations between EEG and fMRI responses, when the analyses are carried out on evoked or induced oscillations (spectral perturbations) in separate frequency bands instead of the time-domain ERP peaks.
Multimodal Quantitative Neuroimaging Databases and Methods: The Cuban Human Brain Mapping Project
Authors: Hernandez-Gonzalez Gertrudis , Bringas-Vega Maria L. , Galán-Garcia Lidice , Bosch-Bayard Jorge , Lorenzo-Ceballos Yenisleidy , Melie-Garcia Lester , Valdes-Urrutia Lourdes , Cobas-Ruiz Marcia , Valdes-Sosa Pedro A. ,   Cuban Human Brain Mapping Project (CHBMP)
Published: February 2012

This article reviews the contributions of the Cuban Neuroscience Center to the evolution of the statistical parametric mapping (SPM) of quantitative Multimodal Neuroimages (qMN), from its inception to more recent work. Attention is limited to methods that compare individual qMN to normative databases (n/qMN). This evolution is described in three successive stages: (a) the development of one variant of normative topographical quantitative EEG (n/qEEG-top) which carries out statistical comparison of individual EEG spectral topographies with regard to a normative database — as part of the now popular SPM of brain descriptive parameters; (b) the development of n/qEEG tomography (n/qEEG-TOM), which employs brain electrical tomography (BET) to calculate voxelwise SPM maps of source spectral features with respect to a norm; (c) the development of a more general n/qMN by substituting EEG parameters with other neuroimaging descriptive parameters to obtain SPM maps. The study also describes the creation of Cuban normative databases, starting with the Cuban EEG database obtained in the early 90s, and more recently, the Cuban Human Brain Mapping Project (CHBMP). This project has created a 240 subject database of the normal Cuban population, obtained from a population-based random sample, comprising clinical, neuropsychological, EEG, MRI and SPECT data for the same subjects. Examples of clinical studies using qMN are given and, more importantly, receiver operator characteristics (ROC) analyses of the different developments document a sustained effort to assess the clinical usefulness of the techniques.
Identification of wounding and topping responsive small RNAs in tobacco (Nicotiana tabacum)
Authors: Tang She , Wang Yu , Li Zefeng , Gui Yijie , Xiao Bingguang , Xie Jiahua , Zhu Qian-Hao , Fan Longjiang 
Published: February 2012

Abstract

Background
MicroRNAs (miRNAs) and short interfering RNAs (siRNAs) are two major classes of small RNAs. They play important regulatory roles in plants and animals by regulating transcription, stability and/or translation of target genes in a sequence-complementary dependent manner. Over 4,000 miRNAs and several classes of siRNAs have been identified in plants, but in tobacco only computational prediction has been performed and no tobacco-specific miRNA has been experimentally identified. Wounding is believed to induce defensive response in tobacco, but the mechanism responsible for this response is yet to be uncovered.

Results
To get insight into the role of small RNAs in damage-induced responses, we sequenced and analysed small RNA populations in roots and leaves from wounding or topping treated tobacco plants. In addition to confirmation of expression of 27 known miRNA families, we identified 59 novel tobacco-specific miRNA members of 38 families and a large number of loci generating phased 21- or 24-nt small RNAs (including ta-siRNAs). A number of miRNAs and phased small RNAs were found to be responsive to wounding or topping treatment. Targets of small RNAs were further surveyed by degradome sequencing.

Conclusions
The expression changes of miRNAs and phased small RNAs responsive to wounding or topping and identification of defense related targets for these small RNAs suggest that the inducible defense response in tobacco might be controlled by pathways involving small RNAs.
The relationship between low back pain and leisure time physical activity in a working population of cleaners - a study with weekly follow-ups for 1 year
Authors: Jespersen Tobias , Jørgensen Marie B , Hansen Jørgen V , Holtermann Andreas , Søgaard Karen 
Published: February 2012

Abstract

Background
Low back pain (LBP) and leisure time physical activity (LTPA) are considered to be closely related, and clinical guidelines for the treatment of acute LBP recommend patients stay physically active. However, the documentation for this recommendation is sparse and based on studies involving patient populations. The purpose of the study was (1) to investigate the correlation between LBP and LTPA on a weekly basis over the course of a year in a high-risk group of cleaners; and (2) to investigate if maintaining LTPA during an episode of acute LBP has a positive effect on LBP intensity in the subsequent 4 weeks.

Methods
188 cleaners consented to participate in a 52-week text message survey about hours of LTPA and intensity of LBP (from 0 to 9) over the previous 7 days. The correlation between LBP and LTPA was calculated by Pearson correlation coefficient. During an episode of acute LBP, a mixed effect logistic regression model was used to investigate whether cleaners who maintain LTPA have a lower pain intensity and higher probability of returning to initial pain intensity within the following four weeks compared with cleaners who decrease LTPA during acute LBP.

Results
The correlation between weekly LTPA and LBP data was negative, but numerically low (r = -0.069) and statistically insignificant (p = 0.08). Among the 82 cleaners experiencing at least one episode of acute LBP, those maintaining LTPA during an episode of acute LBP did not have a lower pain intensity (average LBP intensity difference between groups of 0.06; 95% confidence interval (95% CI) of -0.417 to 0.539) or higher probability of returning to initial pain level (Odds ratio 1,02; 95% CI of 0.50 to 2.09) in the following four weeks compared with cleaners decreasing LTPA during acute LBP.

Conclusions
Hours of LTPA and intensity of LBP measured on a weekly basis throughout a year showed no close correlation. Maintaining LTPA during an episode of acute LBP did not result in a positive effect on LBP in the following 4 weeks. Documentation of LTPA recommendations for acute LBP in working populations is still needed.
Nanoscale anisotropic plastic deformation in single crystal GaN
Authors: Huang Jun , Xu Ke , Fan Ying Min , Niu Mu Tong , Zeng Xiong Hui , Wang Jian Feng , Yang Hui 
Published: February 2012

Abstract
Elasto-plastic mechanical deformation behaviors of c-plane (0001) and nonpolar GaN single crystals are studied using nanoindentation, cathodoluminescence, and transmission electron microscopy. Nanoindentation tests show that c-plane GaN is less susceptible to plastic deformation and has higher hardness and Young's modulus than the nonpolar GaN. Cathodoluminescence and transmission electron microscopy characterizations of indent-induced plastic deformation reveal that there are two primary slip systems for the c-plane GaN, while there is only one most favorable slip system for the nonplane GaN. We suggest that the anisotropic elasto-plastic mechanical properties of GaN are relative to its anisotropic plastic deformation behavior.

PACS: 62.20.fq; 81.05.Ea; 61.72.Lk.
Accelerating large-scale protein structure alignments with graphics processing units
Authors: Pang Bin , Zhao Nan , Becchi Michela , Korkin Dmitry , Shyu Chi-Ren 
Published: February 2012

Abstract

Background
Large-scale protein structure alignment, an indispensable tool to structural bioinformatics, poses a tremendous challenge on computational resources. To ensure structure alignment accuracy and efficiency, efforts have been made to parallelize traditional alignment algorithms in grid environments. However, these solutions are costly and of limited accessibility. Others trade alignment quality for speedup by using high-level characteristics of structure fragments for structure comparisons.

Findings
We present ppsAlign, a p arallel p rotein s tructure Align ment framework designed and optimized to exploit the parallelism of Graphics Processing Units (GPUs). As a general-purpose GPU platform, ppsAlign could take many concurrent methods, such as TM-align and Fr-TM-align, into the parallelized algorithm design. We evaluated ppsAlign on an NVIDIA Tesla C2050 GPU card, and compared it with existing software solutions running on an AMD dual-core CPU. We observed a 36-fold speedup over TM-align, a 65-fold speedup over Fr-TM-align, and a 40-fold speedup over MAMMOTH.

Conclusions

ppsAlign is a high-performance protein structure alignment tool designed to tackle the computational complexity issues from protein structural data. The solution presented in this paper allows large-scale structure comparisons to be performed using massive parallel computing power of GPU.