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[PMID]: 29524805
[Au] Autor:Roh HF; Kim JM
[Ad] Address:Department of Biomedical Science, Hanyang University College of Medicine and Graduate School of Biomedical Science and Engineering, Seoul, South Korea. Electronic address: frank@ngene.org.
[Ti] Title:Noninvasive pulmonary arterial pressure estimation using a logistic-based systolic model.
[So] Source:Comput Biol Med;95:209-216, 2018 Feb 24.
[Is] ISSN:1879-0534
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:RATIONALE: A hemodynamic relationship of pulmonary artery pressure (PAP) to pulmonary acceleration time (PAcT) has not yet been explicitly presented. OBJECTIVE: We employed a logistic-based systolic model with a subtle modification for pulmonary circulation and provided a logical ground for the relationship between systolic PAP and PAcT using transthoracic echocardiography. Additionally, the logistic-based PAP estimation equation was deduced from the model to relate systolic PAP and PAcT. METHODS AND RESULTS: This equation was statistically tested in comparison to existing PAP estimation equations. Results showed that the logistic-based PAP estimation equation was at least as accurate as previous equations with respect to previously published mean PAP versus PAcT values. After the subtle pulmonary modification of the model, the pulmonary blood flow velocity and pressure not only well reflected the underlying pulmonary circulation physiology, but could also be presented in harmony with systemic circulation physiology. CONCLUSIONS: A future clinical study with actual systolic PAP versus PAcT measurements is needed to test the application of the logistic-based PAP estimation equation.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1803
[Cu] Class update date: 180310
[Lr] Last revision date:180310
[St] Status:Publisher

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[PMID]: 29501630
[Au] Autor:Piersma AH; Burgdorf T; Louekari K; Desprez B; Taalman R; Landsiedel R; Barroso J; Rogiers V; Eskes C; Oelgeschläger M; Whelan M; Braeuning A; Vinggaard AM; Kienhuis A; van Benthem J; Ezendam J
[Ad] Address:National Institute for Public Health and the Environment (RIVM), Center for Health Protection, Bilthoven, Netherlands; Institute for Risk Assessment Sciences, Utrecht University, Netherlands. Electronic address: aldert.piersma@rivm.nl.
[Ti] Title:Workshop on acceleration of the validation and regulatory acceptance of alternative methods and implementation of testing strategies.
[So] Source:Toxicol In Vitro;50:62-74, 2018 Mar 02.
[Is] ISSN:1879-3177
[Cp] Country of publication:England
[La] Language:eng
[Ab] Abstract:This report describes the proceedings of the BfR-RIVM workshop on validation of alternative methods which was held 23 and 24 March 2017 in Berlin, Germany. Stakeholders from governmental agencies, regulatory authorities, universities, industry and the OECD were invited to discuss current problems concerning the regulatory acceptance and implementation of alternative test methods and testing strategies, with the aim to develop feasible solutions. Classical validation of alternative methods usually involves one to one comparison with the gold standard animal study. This approach suffers from the reductionist nature of an alternative test as compared to the animal study as well as from the animal study being considered as the gold standard. Modern approaches combine individual alternatives into testing strategies, for which integrated and defined approaches are emerging at OECD. Furthermore, progress in mechanistic toxicology, e.g. through the adverse outcome pathway approach, and in computational systems toxicology allows integration of alternative test battery results into toxicity predictions that are more fine-tuned to the human situation. The road towards transition to a mechanistically-based human-focused hazard and risk assessment of chemicals requires an open mind towards stepping away from the animal study as the gold standard and defining human biologically based regulatory requirements for human hazard and risk assessment.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1803
[Cu] Class update date: 180310
[Lr] Last revision date:180310
[St] Status:Publisher

  3 / 45111 MEDLINE  
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[PMID]: 29458086
[Au] Autor:Rosas-Hernandez H; Cuevas E; Escudero-Lourdes C; Lantz SM; Sturdivant NM; Imam SZ; Sarkar S; Slikker W; Paule MG; Balachandran K; Ali SF
[Ad] Address:Division of Neurotoxicology, National Center for Toxicological Research, 3900 NCTR Road, Jefferson, AR, 72079, USA.
[Ti] Title:Characterization of uniaxial high-speed stretch as an in vitro model of mild traumatic brain injury on the blood-brain barrier.
[So] Source:Neurosci Lett;672:123-129, 2018 Feb 16.
[Is] ISSN:1872-7972
[Cp] Country of publication:Ireland
[La] Language:eng
[Ab] Abstract:Traumatic brain injury (TBI) occurs when external mechanical forces induce brain damage as result of impact, penetration or rapid acceleration/deceleration that causes deformation of brain tissue. Depending on its severity, TBI can be classified as mild, moderate or severe and can lead to blood-brain barrier (BBB) dysfunction. In the present study, we evaluated the effects of uniaxial high-speed stretch (HSS) at 0, 5, 10 and 15% on a pure culture of primary rat brain endothelial cells as an in vitro model of TBI to the BBB. LDH release, viability and apoptosis analysis, expression of tight junction proteins and endothelial permeability were evaluated 24 h after a single stretch episode. HSS slightly increased cell death and apoptosis at 10 and 15%, while LDH release was increased only at 15% stretch. Occludin expression was increased at 10% stretch, while claudin-5 expression was increased at 5% stretch, which also decreased the endothelial permeability. In summary, 15% HSS induced low levels of cell death, consistent with mild TBI and very low percentages of HSS (5%) enhanced the BBB properties, promoting the formation of a stronger barrier. These data support the use of 15% HSS as valuable tool in the study of mild TBI to the BBB in vitro.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1802
[Cu] Class update date: 180310
[Lr] Last revision date:180310
[St] Status:Publisher

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[PMID]: 29360998
[Au] Autor:Tagge CA; Fisher AM; Minaeva OV; Gaudreau-Balderrama A; Moncaster JA; Zhang XL; Wojnarowicz MW; Casey N; Lu H; Kokiko-Cochran ON; Saman S; Ericsson M; Onos KD; Veksler R; Senatorov VV; Kondo A; Zhou XZ; Miry O; Vose LR; Gopaul KR; Upreti C; Nowinski CJ; Cantu RC; Alvarez VE; Hildebrandt AM; Franz ES; Konrad J; Hamilton JA; Hua N; Tripodis Y; Anderson AT; Howell GR; Kaufer D; Hall GF; Lu KP; Ransohoff RM; Cleveland RO; Kowall NW; Stein TD; Lamb BT; Huber BR; Moss WC; Friedman A; Stanton PK; McKee AC; Goldstein LE
[Ad] Address:Molecular Aging and Development Laboratory, Boston University School of Medicine, Boston, MA 02118, USA.
[Ti] Title:Concussion, microvascular injury, and early tauopathy in young athletes after impact head injury and an impact concussion mouse model.
[So] Source:Brain;141(2):422-458, 2018 Feb 01.
[Is] ISSN:1460-2156
[Cp] Country of publication:England
[La] Language:eng
[Ab] Abstract:The mechanisms underpinning concussion, traumatic brain injury, and chronic traumatic encephalopathy, and the relationships between these disorders, are poorly understood. We examined post-mortem brains from teenage athletes in the acute-subacute period after mild closed-head impact injury and found astrocytosis, myelinated axonopathy, microvascular injury, perivascular neuroinflammation, and phosphorylated tau protein pathology. To investigate causal mechanisms, we developed a mouse model of lateral closed-head impact injury that uses momentum transfer to induce traumatic head acceleration. Unanaesthetized mice subjected to unilateral impact exhibited abrupt onset, transient course, and rapid resolution of a concussion-like syndrome characterized by altered arousal, contralateral hemiparesis, truncal ataxia, locomotor and balance impairments, and neurobehavioural deficits. Experimental impact injury was associated with axonopathy, blood-brain barrier disruption, astrocytosis, microgliosis (with activation of triggering receptor expressed on myeloid cells, TREM2), monocyte infiltration, and phosphorylated tauopathy in cerebral cortex ipsilateral and subjacent to impact. Phosphorylated tauopathy was detected in ipsilateral axons by 24 h, bilateral axons and soma by 2 weeks, and distant cortex bilaterally at 5.5 months post-injury. Impact pathologies co-localized with serum albumin extravasation in the brain that was diagnostically detectable in living mice by dynamic contrast-enhanced MRI. These pathologies were also accompanied by early, persistent, and bilateral impairment in axonal conduction velocity in the hippocampus and defective long-term potentiation of synaptic neurotransmission in the medial prefrontal cortex, brain regions distant from acute brain injury. Surprisingly, acute neurobehavioural deficits at the time of injury did not correlate with blood-brain barrier disruption, microgliosis, neuroinflammation, phosphorylated tauopathy, or electrophysiological dysfunction. Furthermore, concussion-like deficits were observed after impact injury, but not after blast exposure under experimental conditions matched for head kinematics. Computational modelling showed that impact injury generated focal point loading on the head and seven-fold greater peak shear stress in the brain compared to blast exposure. Moreover, intracerebral shear stress peaked before onset of gross head motion. By comparison, blast induced distributed force loading on the head and diffuse, lower magnitude shear stress in the brain. We conclude that force loading mechanics at the time of injury shape acute neurobehavioural responses, structural brain damage, and neuropathological sequelae triggered by neurotrauma. These results indicate that closed-head impact injuries, independent of concussive signs, can induce traumatic brain injury as well as early pathologies and functional sequelae associated with chronic traumatic encephalopathy. These results also shed light on the origins of concussion and relationship to traumatic brain injury and its aftermath.awx350media15713427811001.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1801
[Cu] Class update date: 180311
[Lr] Last revision date:180311
[St] Status:In-Data-Review
[do] DOI:10.1093/brain/awx350

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[PMID]: 29524209
[Au] Autor:Boyle R; Ehsanian R; Mofrad A; Popova Y; Varelas J
[Ad] Address:Vestibular Biophysics Laboratory, Ames Research Center, NASA, Moffett Field, CA 94035-1000, USA.
[Ti] Title:Morphology of the Utricular Otolith Organ in the Toadfish, Opsanus tau.
[So] Source:J Comp Neurol;, 2018 Mar 10.
[Is] ISSN:1096-9861
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:The utricle provides the vestibular reflex pathways with the sensory codes of inertial acceleration of self motion and head orientation with respect to gravity to control balance and equilibrium. Here we present an anatomical description of this structure in the adult oyster toadfish, and establish a morphological basis for interpretation of subsequent functional studies. Light, scanning and transmission electron microscopy techniques were applied to visualize the sensory epithelium at varying levels of detail, its neural innervation and its synaptic organization. Scanning electron microscopy was used to visualize otolith mass and morphological polarization patterns of hair cells. Afferent nerve fibers were visualized following labeling with biocytin, and light microscope images were used to make three-dimensional (3-D) reconstructions of individual labeled afferents to identify dendritic morphology with respect to epithelial location. Transmission electron micrographs were compiled to create a serial 3-D reconstruction of a labeled afferent over a segment of its dendritic field and to examine the cell-afferent synaptic contacts. Major observations are: a well-defined striola, medial and lateral extra-striolar regions with a zonal organization of hair bundles; prominent lacinia projecting laterally; dependence of hair cell density on macular location; narrow afferent dendritic fields that follow the hair bundle polarization; synaptic specializations issued by afferents are typically directed towards a limited number of 7-13 hair cells, but larger dendritic fields in the medial extra-striola can be associated with > 20 hair cells also; and hair cell synaptic bodies can be confined to only an individual afferent or can synapse upon several afferents. This article is protected by copyright. All rights reserved.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1803
[Cu] Class update date: 180310
[Lr] Last revision date:180310
[St] Status:Publisher
[do] DOI:10.1002/cne.24429

  6 / 45111 MEDLINE  
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[PMID]: 29523480
[Au] Autor:Chauffour C; Pouly JL; Gremeau AS
[Ad] Address:Département de gynécologie-obstétrique et de reproduction humaine, CHU Estaing, place Lucie-et-Raymond-Aubrac, 63003 Clermont-Ferrand, France. Electronic address: candicechauffour@gmail.com.
[Ti] Title:Prise en charge en FIV en cas d'endométriose, RPC Endométriose CNGOF-HAS. [Management by assisted reproductive technology in women with endometriosis: CNGOF-HAS Endometriosis Guidelines].
[So] Source:Gynecol Obstet Fertil Senol;, 2018 Mar 06.
[Is] ISSN:2468-7189
[Cp] Country of publication:France
[La] Language:fre
[Ab] Abstract:Should the presence of endometriosis change the management of assisted reproductive technology? There is no difference in pregnancy rate after IVF between an agonist or antagonist protocol in patients with endometriosis, so the choice between one or the other of these protocols is free. But the review of the literature has shown an improvement in the chances of pregnancy in case of prolonged ovulation suppression before stimulation for IVF with a GnRH agonist analogue or with oral contraception, especially in cases of severe endometriosis. Endometriosis, regardless of the stage and type of lesions, would have no effect on the IVF results in terms of pregnancy rate and live birth rate, but with a lower number of oocytes collected, especially in cases of severe endometriosis. In a context of superficial endometriosis without pain and of infertility, surgical treatment of superficial endometriosis is not recommended just to increase the chances of pregnancy in IVF. Surgery may have a place in case of failure of IVF to improve the results of the ART. In case of recurrence of endometriosis, surgery is not better than IVF, a medico-surgical concertation is recommended. In addition, studies on ovulation stimulation for IVF do not show any aggravation of the symptoms associated with endometriosis lesions, or an acceleration of its progression, or an increase in the rate of recurrence of the disease.
[Pt] Publication type:ENGLISH ABSTRACT; JOURNAL ARTICLE
[Em] Entry month:1803
[Cu] Class update date: 180310
[Lr] Last revision date:180310
[St] Status:Publisher

  7 / 45111 MEDLINE  
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[PMID]: 29523052
[Au] Autor:Stegemöller EL; Tatz JR; Warnecke A; Hibbing P; Bates B; Zaman A
[Ad] Address:1 Iowa State University.
[Ti] Title:Influence of Music Style and Rate on Repetitive Finger Tapping.
[So] Source:Motor Control;:1-14, 2018 Mar 09.
[Is] ISSN:1087-1640
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:Auditory cues, including music, are commonly used in the treatment of persons with Parkinson's disease. Yet, how music style and movement rate modulate movement performance in persons with Parkinson's disease have been neglected and remain limited in healthy young populations. The purpose of this study was to determine how music style and movement rate influence movement performance in healthy young adults. Healthy participants were asked to perform repetitive finger movements at two pacing rates (70 and 140 beats per minute) for the following conditions: (a) a tone only, (b) activating music, and (c) relaxing music. Electromyography, movement kinematics, and variability were collected. Results revealed that the provision of music, regardless of style, reduced amplitude variability at both pacing rates. Intermovement interval was longer, and acceleration variability was reduced during both music conditions at the lower pacing rate only. These results may prove beneficial for designing therapeutic interventions for persons with Parkinson's disease.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1803
[Cu] Class update date: 180310
[Lr] Last revision date:180310
[St] Status:Publisher
[do] DOI:10.1123/mc.2017-0081

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[PMID]: 29522557
[Au] Autor:Li M; Chadda KR; Matthews GDK; Marr CM; Huang CL; Jeevaratnam K
[Ad] Address:Physiological Laboratory, University of Cambridge, Cambridge, United Kingdom.
[Ti] Title:Cardiac electrophysiological adaptations in the equine athlete-Restitution analysis of electrocardiographic features.
[So] Source:PLoS One;13(3):e0194008, 2018.
[Is] ISSN:1932-6203
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:Exercising horses uniquely accommodate 7-8-fold increases in heart rate (HR). The present experiments for the first time analysed the related adaptations in action potential (AP) restitution properties recorded by in vivo telemetric electrocardiography from Thoroughbred horses. The horses were subjected to a period of acceleration from walk to canter. The QRS durations, and QT and TQ intervals yielded AP conduction velocities, AP durations (APDs) and diastolic intervals respectively. From these, indices of active, λ = QT/(QRS duration), and resting, λ0 = TQ/(QRS duration), AP wavelengths were calculated. Critical values of QT and TQ intervals, and of λ and λ0 at which plots of these respective pairs of functions showed unity slope, were obtained. These were reduced by 38.9±2.7% and 86.2±1.8%, and 34.1±3.3% and 85.9±1.2%, relative to their resting values respectively. The changes in λ were attributable to falls in QT interval rather than QRS duration. These findings both suggested large differences between the corresponding critical (129.1±10.8 or 117.4±5.6 bpm respectively) and baseline HRs (32.9±2.1 (n = 7) bpm). These restitution analyses thus separately identified concordant parameters whose adaptations ensure the wide range of HRs over which electrophysiological activation takes place in an absence of heart block or arrhythmias in equine hearts. Since the horse is amenable to this in vivo electrophysiological analysis and displays a unique wide range of heart rates, it could be a novel cardiac electrophysiology animal model for the study of sudden cardiac death in human athletes.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1803
[Cu] Class update date: 180309
[Lr] Last revision date:180309
[St] Status:In-Data-Review
[do] DOI:10.1371/journal.pone.0194008

  9 / 45111 MEDLINE  
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[PMID]: 29522401
[Au] Autor:Montesinos L; Castaldo R; Pecchia L
[Ti] Title:Wearable Inertial Sensors for Fall Risk Assessment and Prediction in Older Adults: A Systematic Review and Meta-Analysis.
[So] Source:IEEE Trans Neural Syst Rehabil Eng;26(3):573-582, 2018 Mar.
[Is] ISSN:1558-0210
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:Wearable inertial sensors have been widely investigated for fall risk assessment and prediction in older adults. However, heterogeneity in published studies in terms of sensor location, task assessed and features extracted is high, making challenging evidence-based design of new studies and/or real-life applications. We conducted a systematic review and meta-analysis to appraise the best available evidence in the field. Namely, we applied established statistical methods for the analysis of categorical data to identify optimal combinations of sensor locations, tasks, and feature categories. We also conducted a meta-analysis on sensor-based features to identify a set of significant features and their pivot values. The results demonstrated that with a walking test, the most effective feature to assess the risk of falling was the velocity with the sensor placed on the shins. Conversely, during quite standing, linear acceleration measured at the lower back was the most effective combination of feature-placement. Similarly, during the sit-to-stand and/or the stand-to-sit tests, linear acceleration measured at the lower back seems to be the most effective feature-placement combination. The meta-analysis demonstrated that four features resulted significantly higher in fallers: the root-mean-square acceleration in the mediolateral direction during quiet standing with eyes closed [Mean Difference (MD): 0.01 g; 95% Confidence Interval (CI95%): 0.006 to 0.014]; the number of steps (MD: 1.638 steps; CI95%: 0.384 to 2.892) and total time (MD: 2.274 seconds; CI95%: 0.531 to 4.017) to complete the timed up and go test; and the step time (MD: 0.053; CI95%: 0.012 to 0.095; p = 0.01) during walking.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1803
[Cu] Class update date: 180309
[Lr] Last revision date:180309
[St] Status:In-Data-Review
[do] DOI:10.1109/TNSRE.2017.2771383

  10 / 45111 MEDLINE  
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[PMID]: 29496627
[Au] Autor:Nadein K; Betz O
[Ad] Address:Senckenberg German Entomological Institute, Eberswalder Str. 90, 15374, Müncheberg, Germany. Electronic address: k.nadein@gmail.com.
[Ti] Title:Jumping mechanisms and performance in beetles. II. Weevils (Coleoptera: Curculionidae: Rhamphini).
[So] Source:Arthropod Struct Dev;, 2018 Mar 06.
[Is] ISSN:1873-5495
[Cp] Country of publication:England
[La] Language:eng
[Ab] Abstract:We describe the kinematics and performance of the natural jump in the weevil Orchestes fagi (Fabricius, 1801) (Coleoptera: Curculionidae) and its jumping apparatus with underlying anatomy and functional morphology. In weevils, jumping is performed by the hind legs and involves the extension of the hind tibia. The principal structural elements of the jumping apparatus are (1) the femoro-tibial joint, (2) the metafemoral extensor tendon, (3) the extensor ligament, (4) the flexor ligament, (5) the tibial flexor sclerite and (6) the extensor and flexor muscles. The kinematic parameters of the jump (from minimum to maximum) are 530-1965 m s (acceleration), 0.7-2.0 m s (velocity), 1.5-3.0 ms (time to take-off), 0.3-4.4 µJ (kinetic energy) and 54-200 (g-force). The specific joint power as calculated for the femoro-tibial joint during the jumping movement is 0.97 W g . The full extension of the hind tibia during the jump was reached within up to 1.8-2.5 ms. The kinematic parameters, the specific joint power and the time for the full extension of the hind tibia suggest that the jump is performed via a catapult mechanism with an input of elastic strain energy. A resilin-bearing elastic extensor ligament that connects the extensor tendon and the tibial base is considered to be the structure that accumulates the elastic strain energy for the jump. According to our functional model, the extensor ligament is loaded by the contraction of the extensor muscle, while the co-contraction of the antagonistic extensor and flexor muscles prevents the early extension of the tibia. This is attributable to the leverage factors of the femoro-tibial joint providing a mechanical advantage for the flexor muscles over the extensor muscles in the fully flexed position. The release of the accumulated energy is performed by the rapid relaxation of the flexor muscles resulting in the fast extension of the hind tibia propelling the body into air.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1803
[Cu] Class update date: 180310
[Lr] Last revision date:180310
[St] Status:Publisher


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