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https://www.readbyqxmd.com/read/28713053/perils-of-intraoperative-neurophysiologic-monitoring-analysis-of-false-negative-results-in-spine-surgeries
#1
Arvydas Tamkus, Kent S Rice, Michael McCaffrey
BACKGROUND CONTEXT: Although some authors published case reports describing false negatives in intraoperative neurophysiologic monitoring (IONM), systematic review of causes of false negative IONM results is lacking. PURPOSE: The objective was to analyze false negative IONM findings in spine surgery. STUDY DESIGN: Retrospective cohort analysis PATIENT SAMPLE: A cohort of 109 patients with new postoperative neurological deficits was analyzed for possible false negative IONM reporting...
July 13, 2017: Spine Journal: Official Journal of the North American Spine Society
https://www.readbyqxmd.com/read/28708655/utility-of-brainstem-trigeminal-evoked-potentials-in-patients-with-primary-trigeminal-neuralgia-treated-by-microvascular-decompression
#2
Jin Zhu, Xin Zhang, Hua Zhao, Yin-Da Tang, Ting-Ting Ying, Shi-Ting Li
OBJECTIVE: To investigate the characteristics of brainstem trigeminal evoked potentials (BTEP) waveform in patients with and without trigeminal neuralgia (TN), and to discuss the utility of BTEP in patients with primary TN treated by microvascular decompression (MVD). METHODS: A retrospective review of 43 patients who underwent BTEP between January 2016 and June 2016, including 33 patients with TN who underwent MVD and 10 patients without TN. Brainstem trigeminal evoked potentials characteristics of TN and non-TN were summarized, in particular to compare the BTEP changes between pre- and post-MVD, and to discover the relationship between BTEP changes and surgical outcome...
July 13, 2017: Journal of Craniofacial Surgery
https://www.readbyqxmd.com/read/28701550/the-influence-of-envelope-waveform-on-itd-sensitivity-of-neurons-in-the-auditory-midbrain
#3
David Greenberg, Jessica Josephine Margaret Monaghan, Mathias Dietz, Torsten Marquardt, David McAlpine
Interaural time differences (ITDs) conveyed by the modulated envelopes of high-frequency sounds can serve as a cue for localising a sound source. Klein-Hennig et al. (2011) demonstrated the envelope attack, the rate at which stimulus energy in the envelope increases, and the duration of the pause, the interval between successive envelope pulses, as important factors affecting sensitivity to envelope ITDs in human listeners. Modulated sounds with rapid attacks and long pauses produce the lowest ITD-discrimination thresholds...
July 12, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28699322/a-respiratory-marker-derived-from-left-vagus-nerve-signals-recorded-with-implantable-cuff-electrodes
#4
Cristian Sevcencu, Thomas N Nielsen, Benedict Kjaergaard, Johannes J Struijk
OBJECTIVE: Left vagus nerve (LVN) stimulation (LVNS) has been tested for lowering the blood pressure (BP) in patients with resistant hypertension (RH). Whereas, closed-loop LVNS (CL-LVNS) driven by a BP marker may be superior to open-loop LVNS, there are situations (e.g., exercising) when hypertension is normal. Therefore, an ideal anti-RH CL-LVNS system requires a variable to avoid stimulation in such conditions, for example, a respiratory marker ideally extracted from the LVN. As the LVN conducts respiratory signals, this study aimed to investigate if such signals can be recorded using implantable means and if a marker to monitor respiration could be derived from such recordings...
July 11, 2017: Neuromodulation: Journal of the International Neuromodulation Society
https://www.readbyqxmd.com/read/28676704/biomaterial-free-three-dimensional-bioprinting-of-cardiac-tissue-using-human-induced-pluripotent-stem-cell-derived-cardiomyocytes
#5
Chin Siang Ong, Takuma Fukunishi, Huaitao Zhang, Chen Yu Huang, Andrew Nashed, Adriana Blazeski, Deborah DiSilvestre, Luca Vricella, John Conte, Leslie Tung, Gordon F Tomaselli, Narutoshi Hibino
We have developed a novel method to deliver stem cells using 3D bioprinted cardiac patches, free of biomaterials. Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), fibroblasts (FB) and endothelial cells (EC) were aggregated to create mixed cell spheroids. Cardiac patches were created from spheroids (CM:FB:EC = 70:15:15, 70:0:30, 45:40:15) using a 3D bioprinter. Cardiac patches were analyzed with light and video microscopy, immunohistochemistry, immunofluorescence, cell viability assays and optical electrical mapping...
July 4, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28666708/sound-offset-related-brain-potentials-show-retained-sensory-processing-but-increased-cognitive-control-activity-in-older-adults
#6
János Horváth, Zsófia Anna Gaál, Márta Volosin
It has been hypothesized that age-related hearing loss is caused not only by peripheral but also central changes in the auditory system. Many studies used event-related potentials (ERPs) elicited by sound onsets to characterize the age-related differences in central auditory processing. Age-related ERP enhancements in such studies have often been interpreted in terms of elevated sensitivity to auditory stimulation. Such ERPs, however, comprise various components reflecting different aspects of auditory and task-related processing...
June 6, 2017: Neurobiology of Aging
https://www.readbyqxmd.com/read/28662588/utilization-of-multiple-spinal-cord-stimulation-scs-waveforms-in-chronic-pain-patients
#7
Anthony P Berg, Nitzan Mekel-Bobrov, Edward Goldberg, Dat Huynh, Roshini Jain
BACKGROUND: Advances in spinal cord stimulation (SCS) have improved patient outcomes, leading to its increased utilization for chronic pain. Chronic pain is dynamic showing exacerbations, variable severity, and evolving pain patterns. Given this complexity, SCS systems that provide a broad range of stimulation waveforms may be valuable. METHODS: The aim of this research was to characterize the usage pattern of stimulation waveforms and field shapes in chronic pain patients implanted with the Spectra System...
July 12, 2017: Expert Review of Medical Devices
https://www.readbyqxmd.com/read/28660445/serum-adipocyte-fatty-acid-binding-protein-level-is-associated-with-arterial-stiffness-quantified-with-cardio-ankle-vascular-index-in-kidney-transplant-patients
#8
Yen-Cheng Chen, Bang-Gee Hsu, Chung-Jen Lee, Ching-Chun Ho, Guan-Jin Ho, Ming-Che Lee
BACKGROUND: Arterial stiffness is an established marker of cardiovascular risk and an independent predictor of cardiovascular disease (CVD) events and mortality in kidney transplant (KT) patients. Adipocyte fatty acid-binding protein (A-FABP), a novel adipokine, is positively associated with atherosclerosis. The present study evaluated the relationship between fasting circulating A-FABP and peripheral arterial stiffness using the cardio-ankle vascular index (CAVI) in KT patients. METHODS: Fasting blood samples were collected from 74 KT patients, and serum A-FABP levels were measured using an enzyme immunoassay...
June 28, 2017: Clinical and Experimental Nephrology
https://www.readbyqxmd.com/read/28659825/brain-activation-by-h1-antihistamines-challenges-conventional-view-of-their-mechanism-of-action-in-motion-sickness-a-behavioral-c-fos-and-physiological-study-in-suncus-murinus-house-musk-shrew
#9
Longlong Tu, Zengbing Lu, Karolina Dieser, Christina Schmitt, Sze Wa Chan, Man P Ngan, Paul L R Andrews, Eugene Nalivaiko, John A Rudd
Motion sickness occurs under a variety of circumstances and is common in the general population. It is usually associated with changes in gastric motility, and hypothermia, which are argued to be surrogate markers for nausea; there are also reports that respiratory function is affected. As laboratory rodents are incapable of vomiting, Suncus murinus was used to model motion sickness and to investigate changes in gastric myoelectric activity (GMA) and temperature homeostasis using radiotelemetry, whilst also simultaneously investigating changes in respiratory function using whole body plethysmography...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28646801/the-effects-of-exposure-to-low-frequency-electromagnetic-fields-on-male-fertility
#10
Mahsa Darbandi, Sara Darbandi, Ashok Agarwal, Ralf Henkle, Mohammad Reza Sadeghi
Context • People are increasingly exposed to low frequency (LF) electromagnetic fields (EMFs), mainly from electricity distribution networks and electronic devices. Critics of this widespread exposure believe that it can have detrimental effects on the human body. On the other hand, many in vivo and in vitro studies have claimed that low frequency electromagnetic therapy can function as a form of alternative medicine and that therapists can treat disease by applying electromagnetic radiation or pulsed EMFs to the body or cells...
June 23, 2017: Alternative Therapies in Health and Medicine
https://www.readbyqxmd.com/read/28636944/transduction-of-repetitive-mechanical-stimuli-by-piezo1-and-piezo2-ion-channels
#11
Amanda H Lewis, Alisa F Cui, Malcolm F McDonald, Jörg Grandl
Several cell types experience repetitive mechanical stimuli, including vein endothelial cells during pulsating blood flow, inner ear hair cells upon sound exposure, and skin cells and their innervating dorsal root ganglion (DRG) neurons when sweeping across a textured surface or touching a vibrating object. While mechanosensitive Piezo ion channels have been clearly implicated in sensing static touch, their roles in transducing repetitive stimulations are less clear. Here, we perform electrophysiological recordings of heterologously expressed mouse Piezo1 and Piezo2 responding to repetitive mechanical stimulations...
June 20, 2017: Cell Reports
https://www.readbyqxmd.com/read/28628659/wave-intensity-of-aortic-root-pressure-as-diagnostic-marker-of-left-ventricular-systolic-dysfunction
#12
Bernhard Hametner, Stephanie Parragh, Thomas Weber, Siegfried Wassertheurer
BACKGROUND: Systolic left ventricular function strongly influences the blood pressure waveform. Therefore, pressure-derived parameters might potentially be used as non-invasive, diagnostic markers of left ventricular impairment. The aim of this study was to investigate the performance of pressure-based parameters in combination with electrocardiography (ECG) for the detection of left ventricular systolic dysfunction defined as severely reduced ejection fraction (EF). METHODS AND RESULTS: Two populations, each comprising patients with reduced EF and pressure-matched controls, were included for the main analysis (51/102 patients) and model testing (44/88 patients)...
2017: PloS One
https://www.readbyqxmd.com/read/28622745/sex-differences-in-vascular-stiffness-and-relationship-to-the-risk-of-renal-functional-decline-in-patients-with-type-2-diabetes
#13
Kenneth A Earle, Lauren Ng, Sarah White, Karima Zitouni
BACKGROUND: Recent data suggest that the higher risk of end-stage renal disease in women compared with men is associated with waist circumference. We investigated whether vascular stiffness which is linked to visceral fat accumulation is gender specific and associated with a loss in renal function. METHODS: We studied 166 patients with type 2 diabetes at high risk of progressive renal disease. A vascular stiffness index was derived from measurement of the peripheral arterial pulse waveform using infrared finger photoplethysmography...
July 2017: Diabetes & Vascular Disease Research
https://www.readbyqxmd.com/read/28620319/vascular-endothelial-growth-factor-b-induces-a-distinct-electrophysiological-phenotype-in-mouse-heart
#14
Nikolay Naumenko, Jenni Huusko, Tomi Tuomainen, Jussi T Koivumäki, Mari Merentie, Erika Gurzeler, Kari Alitalo, Riikka Kivelä, Seppo Ylä-Herttuala, Pasi Tavi
Vascular endothelial growth factor B (VEGF-B) is a potent mediator of vascular, metabolic, growth, and stress responses in the heart, but the effects on cardiac muscle and cardiomyocyte function are not known. The purpose of this study was to assess the effects of VEGF-B on the energy metabolism, contractile, and electrophysiological properties of mouse cardiac muscle and cardiac muscle cells. In vivo and ex vivo analysis of cardiac-specific VEGF-B TG mice indicated that the contractile function of the TG hearts was normal...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28614281/transcranial-motor-evoked-potential-alarm-criteria-to-predict-foot-drop-injury-during-lumbosacral-surgery
#15
Arvydas Tamkus, Kent S Rice, Gregory Hoffman
STUDY DESIGN: Retrospective cohort analysis. OBJECTIVE: This study aims to investigate whether waveform alterations in transcranial motor evoked potentials (TCMEP) can reliably predict postoperative foot drop. SUMMARY OF BACKGROUND DATA: Nerve injury leading to foot drop is a potential complication of lumbosacral surgery. Very limited data exist on the use of intraoperative TcMEPs to identify iatrogenic foot drop. METHODS: We retrospectively reviewed neuromonitoring data from 130 consecutive spine surgeries with instrumentation involving L4-S1...
June 13, 2017: Spine
https://www.readbyqxmd.com/read/28571131/systemic-and-local-effects-of-warm-oxygen-exposure-to-the-lower-extremities-in-healthy-volunteers
#16
Vidya Sunil Joshi, Sunil Subhash Joshi, Maruthy
INTRODUCTION: Warmth to the extremity is known to improve the cutaneous blood flow and tissue perfusion. Oxygen is essential for healing of chronic wounds. Topical oxygen therapy has become standard therapy in management of lower extremity wounds. A combination of local heat and oxygen is likely to be beneficial in many clinical scenarios of non-healing wounds without any systemic effects. AIM: To evaluate the local and systemic effects of the exposure of extremity to warm oxygen in healthy volunteers...
April 2017: Journal of Clinical and Diagnostic Research: JCDR
https://www.readbyqxmd.com/read/28566465/the-stochastic-nature-of-action-potential-backpropagation-in-apical-tuft-dendrites
#17
Shaina M Short, Katerina D Oikonomou, Wen-Liang L Zhou, Corey D Acker, Marko A Popovic, Dejan Zecevic, Srdjan D Antic
In cortical pyramidal neurons, backpropagating action potentials (bAPs) supply Ca(2+) to synaptic contacts on dendrites. To determine whether the efficacy of AP backpropagation into apical tuft dendrites is stable over time, we performed dendritic Ca(2+) and voltage imaging in rat brain slices. We found that the amplitude of bAP-Ca(2+) in apical tuft branches was unstable, as it varied from trial to trial (termed "bAP-Ca(2+) flickering"). Small perturbations in dendritic physiology, such as spontaneous synaptic inputs, channel inactivation, or temperature-induced changes in channel kinetics, can cause bAP flickering...
May 31, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28559807/eeg-and-eye-tracking-signatures-of-target-encoding-during-structured-visual-search
#18
Anne-Marie Brouwer, Maarten A Hogervorst, Bob Oudejans, Anthony J Ries, Jonathan Touryan
EEG and eye tracking variables are potential sources of information about the underlying processes of target detection and storage during visual search. Fixation duration, pupil size and event related potentials (ERPs) locked to the onset of fixation or saccade (saccade-related potentials, SRPs) have been reported to differ dependent on whether a target or a non-target is currently fixated. Here we focus on the question of whether these variables also differ between targets that are subsequently reported (hits) and targets that are not (misses)...
2017: Frontiers in Human Neuroscience
https://www.readbyqxmd.com/read/28528787/inspiratory-phonation-in-baby-voice
#19
Kathleen Wermke, Asin Ahmad Haschemi, Volker Hesse, Michael P Robb
OBJECTIVE: This study aimed to evaluate the developmental occurrence of inspiratory phonations (IPs) in the spontaneous cries of healthy infants across the first 10 weeks of life. STUDY DESIGN: This is a populational retrospective study. PARTICIPANTS: The spontaneous crying of 17 healthy infants (10 were male) was retrospectively investigated. MATERIALS AND METHODS: Sound files of spontaneously uttered cries that were repeatedly recorded once per week for across the first 10 weeks of life were retrospectively analyzed...
May 18, 2017: Journal of Voice: Official Journal of the Voice Foundation
https://www.readbyqxmd.com/read/28520951/non-selective-his-bundle-pacing-with-a-biphasic-waveform-enhancing-septal-resynchronization
#20
Daniel F Ortega, Luis D Barja, Emilio Logarzo, Nicolas Mangani, Analia Paolucci, Maria P Bonomini
Aims: His bundle pacing has shown to prevent detrimental effects from right ventricular apical pacing (RVA) and proved to resynchronize many conduction disturbances cases. However, the extent of His bundle pacing resynchronization is limited. An optimized stimulation waveform could expand this limit when implemented in His bundle pacing sets. In this work, we temporarily implemented RVA and Non-selective His bundle pacing with a biphasic anodal-first waveform (AF-nHB) and compared their effects against sinus rhythm (SR)...
May 17, 2017: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
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