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https://www.readbyqxmd.com/read/28333901/influence-of-the-recurrent-syncope-episodes-on-neurocognitive-functions-in-patients-with-vasovagal-syncope
#1
Joanna Jędrzejczyk-Spaho, Artur Z Pietrucha, Agnieszka Borowiec, Irena Bzukała, Mateusz Wnuk, Ewa Konduracka, Jadwiga Nessler
The aim of study was to evaluate an influence of recurrent syncope episodes on the neurocognitive functions (NCF) in patients with suspected VVS. AIM: The aim of study was to evaluate an influence of recurrent syncope episodes on the neurocognitive functions (NCF) in patients with suspected VVS. MATERIALS AND METHODS: Study population: 24 pts. (16 women) aged 17-70 yrs (mean age 40 years), with suspected VVS, referred to HUTT (head-up tilt test). All pts. underwent initial evaluation regarding to the number and circumstances of the syncopal and/or presyncopal spells...
March 21, 2017: Polski Merkuriusz Lekarski: Organ Polskiego Towarzystwa Lekarskiego
https://www.readbyqxmd.com/read/28320847/multivoxel-pattern-analysis-reveals-3d-place-information-in-the-human-hippocampus
#2
Misun Kim, Kate J Jeffery, Eleanor A Maguire
The spatial world is three-dimensional (3D), and humans and other animals move both horizontally and vertically within it. Extant neuroscientific studies have typically investigated spatial navigation on a horizontal two-dimensional plane, leaving much unknown about how 3D spatial information is represented in the brain. Specifically, horizontal and vertical information may be encoded in the same or different neural structures with equal or unequal sensitivity. Here, we investigated these possibilities using functional MRI (fMRI) while participants were passively moved within a 3D lattice structure as if riding a rollercoaster...
March 20, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28306330/effect-of-changing-the-head-position-on-accuracy-of-transverse-measurements-of-the-maxillofacial-region-made-on-cone-beam-computed-tomography-and-conventional-posterior-anterior-cephalograms
#3
Abbas Shokri, Amirfarhang Miresmaeili, Nasrin Farhadian, Sepideh Falah-Kooshki, Payam Amini, Najmeh Mollaie
OBJECTIVES: This study aimed to assess the effect of head position on the accuracy of transverse measurements of the maxillofacial region on cone beam computed tomography (CBCT) and conventional posterior-anterior (PA) cephalograms. The second objective of this study was to find skull positions with the greatest and smallest effect on transverse measurements in the maxillofacial region. METHODS: PA cephalograms and CBCT scans were obtained from 10 dry human skulls in seven positions namely the central position, 10° and 20° rotations, 10° and 20° tilts and 10° and 20° tips...
March 17, 2017: Dento Maxillo Facial Radiology
https://www.readbyqxmd.com/read/28292884/vascular-conductance-and-muscle-blood-flow-during-exercise-are-altered-by-inspired-oxygen-fraction-and-arterial-perfusion-pressure
#4
Rodrigo Villar, Richard L Hughson
We tested the hypothesis during the combined challenges of altered inspired O2 fraction (FIO2) and posture changes at lower power output regardless of body position that the vascular conductance (VC) recruitment to the exercising muscle would not limit muscle perfusion and estimated O2 delivery (DO2est ). However, in head-down tilt at the higher power output exercise in hypoxia, the recruitment of VC would have a functional limitation which would restrict muscle blood flow (MBF) leading to a limitation in DO2est with consequent increases in metabolic stress...
March 2017: Physiological Reports
https://www.readbyqxmd.com/read/28292276/effect-of-modified-graded-recession-and-anteriorization-on-unilateral-superior-oblique-palsy-a-retrospective-study
#5
Dong Cheol Lee, Se Youp Lee
BACKGROUND: Several inferior oblique (IO) weakening methods exist for correction of superior oblique palsy (SOP). A previously reported method involved recession and anteriorization according to IO overaction (IOOA) grade, which might be subjective and cause upgaze limitation and opposite vertical strabismus. Therefore, this study attempted to examine the efficacy of modified graded recession and anteriorization of the IO muscle in correction of unilateral SOP without resulting in upgaze limitation or opposite vertical strabismus...
March 14, 2017: BMC Ophthalmology
https://www.readbyqxmd.com/read/28291928/quality-assurance-of-a-gimbaled-head-swing-verification-using-feature-point-tracking
#6
Hideharu Miura, Shuichi Ozawa, Tsubasa Enosaki, Atsushi Kawakubo, Fumika Hosono, Kiyoshi Yamada, Yasushi Nagata
To perform dynamic tumor tracking (DTT) for clinical applications safely and accurately, gimbaled head swing verification is important. We propose a quantitative gimbaled head swing verification method for daily quality assurance (QA), which uses feature point tracking and a web camera. The web camera was placed on a couch at the same position for every gimbaled head swing verification, and could move based on a determined input function (sinusoidal patterns; amplitude: ± 20 mm; cycle: 3 s) in the pan and tilt directions at isocenter plane...
January 2017: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/28286774/orthostatic-intolerance-and-postural-orthostatic-tachycardia-syndrome-in-joint-hypermobility-syndrome-ehlers-danlos-syndrome-hypermobility-type-neurovegetative-dysregulation-or-autonomic-failure
#7
Claudia Celletti, Filippo Camerota, Marco Castori, Federica Censi, Laura Gioffrè, Giovanni Calcagnini, Stefano Strano
Background. Joint hypermobility syndrome/Ehlers-Danlos syndrome, hypermobility type (JHS/EDS-HT), is a hereditary connective tissue disorder mainly characterized by generalized joint hypermobility, skin texture abnormalities, and visceral and vascular dysfunctions, also comprising symptoms of autonomic dysfunction. This study aims to further evaluate cardiovascular autonomic involvement in JHS/EDS-HT by a battery of functional tests. Methods. The response to cardiovascular reflex tests comprising deep breathing, Valsalva maneuver, 30/15 ratio, handgrip test, and head-up tilt test was studied in 35 JHS/EDS-HT adults...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28270191/isolation-and-molecular-characterisation-of-halicephalobus-gingivalis-in-the-brain-of-a-horse-in-piedmont-italy
#8
Maria Domenica Pintore, Francesco Cerutti, Antonio D'Angelo, Cristiano Corona, Paola Gazzuola, Loretta Masoero, Corrado Colombo, Roberto Bona, Carlo Cantile, Simone Peletto, Cristina Casalone, Barbara Iulini
BACKGROUND: A fatal case of meningoencephalitis was reported in a 13-year-old Koninklijk Warmbloed Paard Nederland stallion, suspected of West Nile virus (WNV) infection, in the Piedmont region of Italy. Clinical signs included right head tilt and circling, depression alternated with excitability, fever and lateral strabismus. Combined treatment consisting of dimethylsulfoxide, dexamethasone, sulphonamides and sedative was administered, but because of the poor conditions the horse was euthanatized and submitted for necropsy...
March 7, 2017: Parasites & Vectors
https://www.readbyqxmd.com/read/28269522/analysis-of-a-cardiovascular-model-for-the-study-of-the-autonomic-response-of-brugada-syndrome-patients
#9
Mireia Calvo, Virginie Le Rolle, Daniel Romero Perez, Nathalie Behar, Pedro Gomis, Philippe Mabo, Alfredo I Hernandez
This paper describes the integration of mathematical models of the cardiac electrical activity, the cardiovascular system and the baroreceptor reflex control of the autonomic nervous system, with a model representing a head-up tilt test. Sensitivity analyses are performed in order to determine those model parameters producing the greatest significant effects on heart rate and blood pressure. An optimization step is then applied to the most influential parameters in order to find the best model fit to real cardiac data obtained from a patient suffering from Brugada syndrome and a healthy subject, in supine and upright postures during a tilt test...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28269114/application-of-a-new-robust-ecg-t-wave-delineation-algorithm-for-the-evaluation-of-the-autonomic-innervation-of-the-myocardium
#10
Matteo Cesari, Jesper Mehlsen, Anne-Birgitte Mehlsen, Helge Bjarup Dissing Sorensen
T-wave amplitude (TWA) is a well know index of the autonomic innervation of the myocardium. However, until now it has been evaluated only manually or with simple and inefficient algorithms. In this paper, we developed a new robust single-lead electrocardiogram (ECG) T-wave delineation algorithm that is able to detect the T-wave with a wavelet based method and automatically calculate the TWA. We evaluated the algorithm on the QT database, achieving a sensitivity of 99.92% for the T wave peak and 99.38% for the T wave end...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28268928/comparison-between-k-nearest-neighbor-approaches-for-conditional-entropy-estimation-application-to-the-assessment-of-the-cardiac-control-in-amyotrophic-lateral-sclerosis-patients
#11
Alberto Porta, Beatrice De Maria, Vlasta Bari, Andrea Marchi, Kalliopi Marinou, Riccardo Sideri, Gabriele Mora, Laura Dalla Vecchia
The study evaluates the k-nearest-neighbor (KNN) strategy for the assessment of complexity of the cardiac neural control from spontaneous fluctuations of heart period (HP). Two different procedures were assessed: i) the KNN estimation of the conditional entropy (CE) proposed by Porta et al; ii) the KNN estimation of mutual information proposed by Kozachenko-Leonenko, refined by Kraskov-Stögbauer-Grassberger and here adapted for the CE estimation. The two procedures were compared over HP variability recordings obtained at rest in supine position and during head-up tilt (HUT) in amyotrophic lateral sclerosis patients and healthy subjects...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28268420/delta-space-plot-analysis-of-cardiovascular-coupling-in-vasovagal-syncope-during-orthostatic-challenge
#12
S Reulecke, S Charleston-Villalobos, A Voss, R Gonzalez-Camarena, M Gaitan-Gonzalez, J Gonzalez-Hermosillo, G Hernandez-Pacheco, T Aljama-Corrales
In this work, a graphical method to study cardiovascular coupling, called delta space plot analysis (DSPA), was introduced. The graphical representation is susceptible to be parameterized in shape and orientation. The usefulness of this technique was studied on cardiovascular data from patients with vasovagal syncope (VVS) and from controls. The study included 15 female patients diagnosed with VVS and 11 age-matched healthy female subjects. All subjects were enrolled in a head-up tilt (HUT) test, breathing normally, including 5 minutes of supine position (baseline) and 18 minutes of 70° orthostatic phase...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28265145/inclination-of-standing-posture-due-to-the-presentation-of-tilted-view-through-an-immersive-head-mounted-display
#13
Yuji Ohmura, Shiro Yano, Junji Katsuhira, Masato Migita, Arito Yozu, Toshiyuki Kondo
[Purpose] The purpose of the present study is to clarify whether tilted scenery presented through an immersive head-mounted display (HMD) causes the inclination of standing posture. [Subjects and Methods] Eleven healthy young adult males who provided informed consent participated in the experiment. An immersive HMD and a stereo camera were employed to develop a visual inclination system. The subjects maintained a standing posture twice for 5s each while wearing the visual inclination system. They performed this task under two conditions: normal view and 20° leftward tilted view...
February 2017: Journal of Physical Therapy Science
https://www.readbyqxmd.com/read/28263259/head-down-posture-in-glaucoma-suspects-induces-changes-in-iop-systemic-pressure-and-perg-that-predict-future-loss-of-optic-nerve-tissue
#14
Vittorio Porciatti, William J Feuer, Pedro Monsalve, Giacinto Triolo, Luis Vazquez, John McSoley, Lori M Ventura
PURPOSE: To obtain pilot data on posture-induced changes of intraocular pressure (IOP), systemic pressure, and pattern electroretinogram (PERG) predictive of future optic nerve tissue loss glaucoma suspects (GSs). METHODS: Mean peripapillary retinal fiber layer thickness (RNFLT) was measured with optical coherence tomography 2 times/year in 28 GS aged 58±8.9 years over 5.0±0.73 years. All patients had a baseline PERG, IOP, and brachial blood pressure measurements in the seated and -10 degrees head-down-body-tilt (HDT) position...
March 3, 2017: Journal of Glaucoma
https://www.readbyqxmd.com/read/28263183/complexity-of-cardiovascular-rhythms-during-head-up-tilt-test-by-entropy-of-patterns
#15
Dorota Wejer, Beata Graff, Danuta Makowiec, Szymon Budrejko, Zbiginiew Struzik
The head-up tilt (HUT) test, which provokes transient dynamical alterations in the regulation of cardiovascular system, provides insights into complex organization of this system. Based on signals with heart period intervals (RR-intervals) and/or systolic blood pressure (SBP), differences in the cardiovascular regulation between vasovagal patients (VVS) and the healthy people group (CG) are investigated. Short-term relations among signal data represented symbolically by three-beat patterns allow to qualify and quantify the complexity of the cardiovascular regulation by Shannon entropy...
March 6, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28262007/muscle-oxygen-saturation-increases-during-head-up-tilt-induced-pre-syncope
#16
A Lund, H Sørensen, T W Jensen, M J Niemann, N D Olesen, H B Nielsen, N V Olsen, N H Secher
AIM: To evaluate whether muscle vasodilatation plays a role for hypotension developed during central hypovolaemia, muscle oxygenation (Sm O2 ) was examined during (pre)syncope induced by head-up tilt (HUT). Skin blood flow (SkBF) and oxygenation (Sskin O2 ) were determined because evaluation of Sm O2 may be affected by superficial tissue oxygenation. Furthermore, we evaluated cerebral oxygenation (Sc O2 ) and middle cerebral artery mean blood flow velocity (MCAvmean ). METHODS: Twenty healthy male volunteers (median age 24 years; range 19-38) were subjected to passive 50° HUT for 1 hour or until (pre)syncope...
March 6, 2017: Acta Physiologica
https://www.readbyqxmd.com/read/28261104/circulating-micrornas-correlated-with-bone-loss-induced-by-45-days-of-bed-rest
#17
Shukuan Ling, Guohui Zhong, Weijia Sun, Fengji Liang, Feng Wu, Hongxing Li, Yuheng Li, Dingsheng Zhao, Jinping Song, Xiaoyan Jin, Xiaorui Wu, Hailin Song, Qi Li, Yinghui Li, Shanguang Chen, Jianghui Xiong, Yingxian Li
The purpose of this study was to find the circulating microRNAs (miRNAs) co-related with bone loss induced by bed rest, and testify whether the selected miRNAs could reflect the bone mineral status of human after bed-rest. We analyzed plasma miRNA levels of 16 subjects after 45 days of -6° head-down tilt bed rest, which is a reliable model for the simulation of microgravity. We characterize the circulating miRNA profile in individuals after bed rest and identify circulating miRNAs which can best reflect the level of bone loss induced by bed rest...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28257745/accuracy-and-head-positioning-effects-on-measurements-of-anterior-tooth-length-using-3-dimensional-and-conventional-dental-panoramic-radiography
#18
Noriyuki Kitai, Manabu Murabayashi, Hiroshi Sugimoto, Atsushi Fujiwara, Wakako Tome, Akitoshi Katsumata
INTRODUCTION: The purposes of this study were to examine the accuracy and the head positioning effects on measurements of anterior tooth length using 3-dimensional (3D) and conventional dental panoramic radiography and to investigate whether 3D panoramic radiography is suitable for the evaluation of anterior tooth length. METHODS: A simulated human head was radiographed at 4, 8, and 12 mm displaced positions, and at 5°, 10°, and 15° tilted positions from the standard head position using 3D and conventional panoramic radiography, and also using cone-beam computed tomography...
March 2017: American Journal of Orthodontics and Dentofacial Orthopedics
https://www.readbyqxmd.com/read/28245206/cerebrovascular-and-cardiovascular-variability-interactions-investigated-through-conditional-joint-transfer-entropy-in-subjects-prone-to-postural-syncope
#19
Vlasta Bari, Beatrice De Maria, Claudio Enrico Mazzucco, Gianluca Rossato, Davide Tonon, Giandomenico Nollo, Luca Faes, Alberto Porta
A model-based conditional transfer entropy approach was exploited to quantify the information transfer in cerebrovascular (CBV) and cardiovascular (CV) systems in subjects prone to develop postural syncope. Spontaneous beat-to-beat variations of mean cerebral blood flow velocity (MCBFV) derived from a transcranial Doppler device, heart period (HP) derived from surface electrocardiogram, mean arterial pressure (MAP) and systolic arterial pressure (SAP) derived from finger plethysmographic arterial pressure device were monitored at rest in supine position (REST) and during 60° head-up tilt (TILT) in 13 individuals (age mean±standard deviation: 28±9 years, min-max range: 18-44 years, 5 males) with a history of recurrent episodes of syncope (SYNC) and in 13 age- and gender-matched controls (NonSYNC)...
February 28, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28242824/gender-differences-in-tibial-microvascular-flow-responses-to-head-down-tilt-and-lower-body-negative-pressure
#20
Jamila H Siamwala, Brandon R Macias, Paul C Lee, Alan R Hargens
The purpose of the investigation was to study lower body negative pressure recovery in response to head down tilt position in men and women. The study examined the primary hypothesis that tibial bone microvascular flow responses to HDT and lower body negative pressure (LBNP) differ in women and men. Nine women and nine men between 20 to 30 years of age participated in the study. Tibial microvascular flow, head and tibial oxygenation and calf circumference were measured using photoplethysmography (PPG), near-infrared spectroscopy (NIRS) and strain gauge plethysmography (SGP), respectively, during sitting (control baseline), supine, 15° HDT, and 15° HDT with 25 mmHg LBNP Tibial microvascular flow with HDT increased by 57% from supine position (from 1...
February 2017: Physiological Reports
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