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https://www.readbyqxmd.com/read/28227523/a-measure-of-cortico-cortical-potentials-evoked-by-10-hz-direct-electrical-stimulation-of-the-brain-and-by-means-of-a-differential-recording-mode-of-electrocorticographic-signals
#1
Marion Vincent, Olivier Rossel, Hugues Duffau, Francois Bonnetblanc, David Guiraud, Marion Vincent, Olivier Rossel, Hugues Duffau, Francois Bonnetblanc, David Guiraud, Olivier Rossel, David Guiraud, Francois Bonnetblanc, Hugues Duffau, Marion Vincent
Direct electrical stimulation (DES) at 60 Hz is used to perform real-time functional mapping of the brain during wide-awake neurosurgery. The electrophysiological effects of DES are largely unknown, locally and at a more remote distance. Here, by lowering the DES frequency to 10 Hz and by using a differential recording mode of electro-corticographic (ECoG) signals to improve the focality, we were able to record cortico-cortical evoked potentials easily with standard current amplitude of stimulation (2 mA). DES applied at 10 Hz and differential recording of ECoG could be used to map on-line the connectivity between different sub-cortical and cortical areas with a higher spatial accuracy...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227502/posterior-tibial-nerve-stimulation-using-a-wirelessly-powered-system-in-anesthetized-cats
#2
Zainab Moazzam, Austin R Duke, Paul B Yoo, Zainab Moazzam, Austin R Duke, Paul B Yoo, Paul B Yoo, Zainab Moazzam, Austin R Duke
Posterior Tibial Nerve Stimulation (PTNS) is an effective overactive bladder (OAB) therapy where electrical pulses are typically delivered once per week in a 12-week stimulation regime. While the mechanism of action remains unknown, effective long-term delivery of PTNS has recently become a subject of concern. To this end, a multi-contact electrode was surgically placed in the hind limb region of anesthetized cats to (1) investigate the feasibility of using a wirelessly powered system to stimulate PTN afferents and (2) characterize implant-driven effects of stimulation frequency on modulating bladder activity...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227320/three-dimensional-modeling-of-physiological-tremor-for-hand-held-surgical-robotic-instruments
#3
Sivanagaraja Tatinati, Yan Naing Aye, Anand Pual, Wei Tech Ang, Kalyana C Veluvolu, Sivanagaraja Tatinati, Yan Naing Aye, Anand Pual, Wei Tech Ang, Kalyana C Veluvolu, Sivanagaraja Tatinati, Anand Pual, Wei Tech Ang, Yan Naing Aye, Kalyana C Veluvolu
Hand-held robotic instruments are developed to compensate physiological tremor in real-time while augmenting the required precision and dexterity into normal microsurgical work-flow. The hardware (sensors and actuators) and software (causal linear filters) employed for tremor identification and filtering introduces time-varying unknown phase-delay that adversely affects the device performance. The current techniques that focus on three-dimensions (3D) tip position control involves modeling and canceling the tremor in 3-axes (x, y, and z axes) separately...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227171/structural-classification-of-protein-sequences-based-on-signal-processing-and-support-vector-machines
#4
Charalambos Chrysostomou, Huseyin Seker, Charalambos Chrysostomou, Huseyin Seker, Huseyin Seker, Charalambos Chrysostomou
The function of any protein depends directly on its secondary and tertiary structure. Proteins can fold into a three-dimensional shape, which is primarily depended on the arrangement of amino acids in the primary structure. In recent years, with the explosive sequencing of proteins, it is unfeasible to perform detailed experimental studies, as these methodologies are very expensive and time consuming. This leaves the structure of the majority of currently available protein sequences unknown. In this paper, a predictive model is therefore presented for the classification of protein sequence's secondary structures, namely alpha helix and beta sheet...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227129/modeling-of-pharyngoesophageal-segment-during-tracheoesophageal-phonation-in-total-laryngectomy-patients-with-preliminary-validation
#5
Teng Zhang, Siwei Bai, Ian Cook, Michal Szczesniak, Julia Maclean, Socrates Dokos, Teng Zhang, Siwei Bai, Ian Cook, Michal Szczesniak, Julia Maclean, Socrates Dokos, Siwei Bai, Michal Szczesniak, Socrates Dokos, Ian Cook, Julia Maclean, Teng Zhang
For patients with large or recurrent laryngeal cancer, total laryngectomy surgery is usually performed. In the absence of a larynx, tracheoesophageal (TE) voice is the gold standard for alaryngeal phonation. The mechanisms underlying TE voice are unknown, but pharyngoesophageal (PE) segment vibration has been shown to play a key role. The aim of this study was to systematically explore the mechanics of PE segment vibration during TE phonation. A 2D axisymmetric finite-element model with two domains representing the air and PE wall was developed...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227087/maximum-likelihood-cardiac-conduction-velocity-estimation-from-sequential-mapping-in-the-presence-of-activation-time-noise-with-unknown-variances
#6
Mohammad Hassan Shariat, Saeed Gazor, Damian Redfearn, Mohammad Hassan Shariat, Saeed Gazor, Damian Redfearn, Mohammad Hassan Shariat, Damian Redfearn
The cardiac conduction velocity (CV) can be estimated by analysing the activation times (ATs) and the locations of the electrodes that are used for the intracardiac electrogram (IEGM) recording. Here, we study the problem of the CV estimation in sequential mapping without using any independent electrogram as a time alignment reference. We assume that the IEGMs are sequentially recorded from several sites, where at each site, at least two of the catheter's electrodes are in contact with the cardiac tissue. We consider the planar wavefront with stable CV that propagates within the recording sites throughout our data collection period...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226984/analysis-of-causal-cardio-postural-interaction-under-orthostatic-stress-using-convergent-cross-mapping
#7
Ajay K Verma, Amanmeet Garg, Andrew Blaber, Reza Fazel-Rezai, Kouhyar Tavakolian, Ajay K Verma, Amanmeet Garg, Andrew Blaber, Reza Fazel-Rezai, Kouhyar Tavakolian, Ajay K Verma, Amanmeet Garg, Kouhyar Tavakolian, Reza Fazel-Rezai, Andrew Blaber
Knowledge of a cause-and-effect relationship between different physiological systems is helpful in predicting their performance under perturbations, such as orthostatic challenge. The causal coupling between representative signals of the cardiovascular and postural systems under orthostatic challenge remains unknown. Understanding the causal relationship between these two systems is critical, as their interplay is vital to maintain stable upright posture of the human body during quiet standing. In this research, convergent cross mapping (CCM) method was applied to study the causal relationship between the cardiovascular and postural systems previously shown to have coherent activity during quiet standing...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226919/an-online-recursive-autocalibration-of-triaxial-accelerometer
#8
Lin Ye, Steven W Su, Dong Lei, Hung T Nguyen, Lin Ye, Steven W Su, Dong Lei, Hung T Nguyen, Steven W Su, Hung T Nguyen, Lin Ye, Dong Lei
In this paper, we proposed a novel method for autocalibration of triaxial Micro-Electro-Mechanical systems (MEMS) accelerometer that does not require any sophisticated laboratory facilities. In particular, this method is an online calibration method which can be conveniently implemented with the accuracy of MEMS accelerometer being significantly improved. The procedure exploits the fact that the output vector of the accelerometer must match the local gravity in static state condition. To achieve online calibration, the model as well as the cost function are linearized at the beginning, and an online recursive method is then utilized to identify the unknown parameters and remove the bias caused by linearization...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226814/detection-of-gait-initiation-failure-in-parkinson-s-disease-patients-using-eeg-signals
#9
Quynh Tran Ly, A M Ardi Handojoseno, Moran Gilat, Nghia Nguyen, Rifai Chai, Yvonne Tran, Simon J G Lewis, Hung T Nguyen, Quynh Tran Ly, A M Ardi Handojoseno, Moran Gilat, Nghia Nguyen, Rifai Chai, Yvonne Tran, Simon J G Lewis, Hung T Nguyen, Nghia Nguyen, A M Ardi Handojoseno, Moran Gilat, Hung T Nguyen, Yvonne Tran, Simon J G Lewis, Quynh Tran Ly, Rifai Chai
Gait Initiation Failure (GIF) is one of the most disabling gait disturbances seen in advanced Parkinson's disease (PD). Gait Initiation is a complex motor task that requires motor and cognitive processing to enable the correct selection, timing and scaling of movement. Failure to initiate the first step often precipitates falls and leads to significant morbidity. However, the brain mechanisms underlying GIF remain unknown. This study utilized an ambulatory electroencephalography (EEG) technique to investigate the brain dynamic changes underlying GIF and aims to detect the occurrence of GIF in four PD patients...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226730/rf-induced-energy-for-partially-implanted-catheters-a-computational-study
#10
Elena Lucano, Micaela Liberti, Tom Lloyd, Francesca Apollonio, Steve Wedan, Wolfgang Kainz, Leonardo M Angelone, Elena Lucano, Micaela Liberti, Tom Lloyd, Francesca Apollonio, Steve Wedan, Wolfgang Kainz, Leonardo M Angelone, Elena Lucano, Leonardo M Angelone, Tom Lloyd, Steve Wedan, Francesca Apollonio, Wolfgang Kainz, Micaela Liberti
Magnetic Resonance Imaging (MRI) is a radiological imaging technique widely used in clinical practice. MRI has been proposed to guide the catheters for interventional procedures, such as cardiac ablation. However, there are risks associated with this procedure, such as RF-induced heating of tissue near the catheters. The aim of this study is to develop a quantitative RF-safety method for patients with partially implanted leads at 64 MHz. RF-induced heating is related to the electric field incident along the catheter, which in turns depends on several variables, including the position of the RF feeding sources and the orientation of the polarization, which are however often unknown...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226700/adaptive-change-point-detection-of-dynamic-functional-connectivity-networks
#11
Sadia Shakil, Sheila D Keilholz, Chin-Hui Lee, Sadia Shakil, Sheila D Keilholz, Chin-Hui Lee, Shella D Keilholz, Chin-Hui Lee, Sadia Shakil
This study presents a new algorithm to adaptively detect change points of functional connectivity networks in the brain. It uses scans from resting-state functional magnetic resonance imaging (rsfMRI) which is one of the major tools to investigate intrinsic brain functionality. Different regions of the resting brain form networks that change states within a few seconds to minutes. The change points of these networks are different in normal and disordered brain functions and their understanding can help in identification of brain disorders...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226663/predicting-seizures-in-untreated-temporal-lobe-epilepsy-using-point-process-nonlinear-models-of-heartbeat-dynamics
#12
G Valenza, A Romigi, L Citi, F Placidi, F Izzi, M Albanese, E P Scilingo, M G Marciani, A Duggento, M Guerrisi, N Toschi, R Barbieri, G Valenza, A Romigi, L Citi, F Placidi, F Izzi, M Albanese, E P Scilingo, M G Marciani, A Duggento, M Guerrisi, N Toschi, R Barbieri, M Guerrisi, F Izzi, F Placidi, A Romigi, E P Scilingo, A Duggento, M Albanese, N Toschi, M G Marciani, R Barbieri, G Valenza, L Citi
Symptoms of temporal lobe epilepsy (TLE) are frequently associated with autonomic dysregulation, whose underlying biological processes are thought to strongly contribute to sudden unexpected death in epilepsy (SUDEP). While abnormal cardiovascular patterns commonly occur during ictal events, putative patterns of autonomic cardiac effects during pre-ictal (PRE) periods (i.e. periods preceding seizures) are still unknown. In this study, we investigated TLE-related heart rate variability (HRV) through instantaneous, nonlinear estimates of cardiovascular oscillations during inter-ictal (INT) and PRE periods...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226546/cardiac-conduction-velocity-estimation-from-sequential-mapping-assuming-known-gaussian-distribution-for-activation-time-estimation-error
#13
Mohammad Hassan Shariat, Saeed Gazor, Damian Redfearn, Mohammad Hassan Shariat, Saeed Gazor, Damian Redfearn, Saeed Gazor, Mohammad Hassan Shariat, Damian Redfearn
In this paper, we study the problem of the cardiac conduction velocity (CCV) estimation for the sequential intracardiac mapping. We assume that the intracardiac electrograms of several cardiac sites are sequentially recorded, their activation times (ATs) are extracted, and the corresponding wavefronts are specified. The locations of the mapping catheter's electrodes and the ATs of the wavefronts are used here for the CCV estimation. We assume that the extracted ATs include some estimation errors, which we model with zero-mean white Gaussian noise values with known variances...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226463/cardiac-katp-channel-modulation-by-16hz-magnetic-fields-a-theoretical-study
#14
Yuval Aharonovich, Mickey Scheinowitz, Sharon Zlochiver, Yuval Aharonovich, Mickey Scheinowitz, Sharon Zlochiver, Yuval Aharonovich, Sharon Zlochiver, Mickey Scheinowitz
Heart exposure to 16Hz magnetic fields (MFs) was shown to be cardio-protective for diseased hearts; still, the mechanism of this effect is unknown. We hypothesize that a possible one mechanism is an increased trans-membrane KATP channel open probability due to modulation of the degree of dissociation between K(+) ions, having a resonance frequency of 16Hz, and the channel selectivity filter. The Fan-Makielski Markovian KATP channel model was adopted, and the MF bio-effect was manifested by modulating the open probability of the channel using the predictive MF bio-effect parameter based on Binhi's quantum mechanics model...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226404/the-effect-of-cortex-medulla-proportions-on-molecular-diagnoses-in-kidney-transplant-biopsies-rejection-and-injury-can-be-assessed-in-medulla
#15
Katelynn S Madill-Thomsen, Roger C Wiggins, Farsad Eskandary, Georg A Böhmig, Philip F Halloran
Histologic assessment of kidney transplant biopsies relies on cortex rather than medulla, but for microarray studies, the proportion cortex in a biopsy is typically unknown and could affect the molecular readings. The present study aimed to develop a molecular estimate of proportion cortex in biopsies and examine its effect on molecular diagnoses. Microarrays from 26 kidney transplant biopsies divided into cortex and medulla components and processed separately showed that many of the most significant differences were in glomerular genes e...
February 22, 2017: American Journal of Transplantation
https://www.readbyqxmd.com/read/28226398/dysregulation-of-interleukin-5-expression-in-familial-eosinophilia
#16
Senbagavalli Prakash Babu, Yun-Yun K Chen, Sandra Bonne-Annee, Jun Yang, Irina Maric, Timothy G Myers, Thomas B Nutman, Amy D Klion
BACKGROUND: Familial eosinophilia (FE) is a rare autosomal dominant inherited disorder characterized by the presence of lifelong peripheral eosinophilia (>1500/μL). Mapped to chromosome 5q31-q33, the genetic cause of FE is unknown, and prior studies have failed to demonstrate a primary abnormality in the eosinophil lineage. OBJECTIVE: The aim of the present study was to identify the cells driving the eosinophilia in FE. METHODS: Microarray analysis and real-time PCR were used to examine transcriptional differences in peripheral blood mononuclear cells (PBMC), and in purified cell subsets from affected and unaffected family members belonging to a single large kindred...
February 22, 2017: Allergy
https://www.readbyqxmd.com/read/28226388/-can-anti-vegf-injections-cause-glaucoma-or-ocular-hypertension
#17
I Lanzl, K Kotliar
An increasing number of patients receive intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections with a high frequency for the treatment of neovascular macular disease. Since the volume of the vitreous body is temporarily increased by the injection of the substances, a short-term intraocular pressure increase after the introduction of the substance is not uncommon. However, there are more and more reports indicating that multiple injections may lead to a long-term increase in intraocular pressure...
February 2017: Klinische Monatsblätter Für Augenheilkunde
https://www.readbyqxmd.com/read/28226288/neural-correlates-of-lexical-decisions-in-parkinson-s-disease-revealed-with-multivariate-extraction-of-cortico-subthalamic-interactions
#18
F U Hohlefeld, A Ewald, F Ehlen, H O Tiedt, A Horn, A A Kühn, G Curio, F Klostermann, V V Nikulin
OBJECTIVE: Neural interactions between cortex and basal ganglia are pivotal for sensorimotor processing. Specifically, coherency between cortex and subthalamic structures is a frequently studied phenomenon in patients with Parkinson's disease. However, it is unknown whether cortico-subthalamic coherency might also relate to cognitive aspects of task performance, e.g., language processing. Furthermore, standard coherency studies are challenged by how to efficiently handle multi-channel recordings...
January 17, 2017: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
https://www.readbyqxmd.com/read/28226265/alterations-of-ubiquitin-related-proteins-in-the-pathology-and-development-of-schizophrenia-evidence-from-human-and-animal-studies
#19
Jessica L Andrews, Frederic J Goodfellow, Natalie Matosin, Mollie K Snelling, Kelly A Newell, Xu-Feng Huang, Francesca Fernandez-Enright
Gene expression analyses in post-mortem schizophrenia brains suggest that a number of ubiquitin proteasome system (UPS) genes are associated with schizophrenia; however the status of UPS proteins in the schizophrenia brain is largely unknown. Ubiquitin related proteins are inherently involved in memory, neuronal survival and morphology, which are processes implicated in neurodevelopmental disorders such as schizophrenia. We examined levels of five UPS proteins (Protein Inhibitor of Activated STAT2 [PIAS2], F-Box and Leucine rich repeat protein 21 [FBXL21], Mouse Double Minute 2 homolog [MDM2], Ubiquitin Carboxyl-Terminal Hydrolase-L1 [UCHL1] and Ubiquitin Conjugating Enzyme E2D1 [UBE2D1]) involved in these neuronal processes, within the dorsolateral prefrontal cortex of post-mortem schizophrenia subjects and matched controls (n = 30/group), in addition to across neurodevelopmental time-points (juvenile, adolescent and adult stages of life), utilizing a well-established neurodevelopmental phencyclidine (PCP) animal model of schizophrenia...
January 18, 2017: Journal of Psychiatric Research
https://www.readbyqxmd.com/read/28226227/protective-and-harmful-immunity-to-rsv-infection
#20
Peter J M Openshaw, Chris Chiu, Fiona J Culley, Cecilia Johansson
Respiratory syncytial virus (RSV) is an exceptional mucosal pathogen. It specializes in infection of the ciliated respiratory epithelium, causing disease of variable severity with little or no direct systemic effects. It infects virtually all children by the age of three years and then repeatedly infects throughout life; this it does despite relatively slight variations in antigenicity, apparently by inducing selective immunological amnesia. Inappropriate or dysregulated responses to RSV can be pathogenic, causing disease-enhancing inflammation that contributes to short- and long-term effects...
February 6, 2017: Annual Review of Immunology
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