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https://www.readbyqxmd.com/read/28107074/analysis-of-the-normal-electrocardiogram-in-wild-rooks-corvus-frugilegus
#1
Hossein Hassanpour, Hossein Abbasi Dehkordi, Mehdi Khosravi, Saeid Soltani, Leila Nasiri
To describe the normal electrocardiographic (ECG) patterns and values in unanesthetized rooks ( Corvus frugilegus ), standard bipolar (I, II, and III) and augmented unipolar limb (aVR, aVL, and aVF) lead ECGs were recorded from 10 clinically healthy wild rooks. Wave forms were analyzed in all leads at 50 mm/s and at 10 mm = 1 mV to determine PR, QRS, ST, and QT durations; the net QRS complex; and P and T amplitudes. The polarity of each waveform was tabulated in all leads. The mean electrical axis (MEA) for the frontal plane was counted by using leads II and III...
December 2016: Journal of Avian Medicine and Surgery
https://www.readbyqxmd.com/read/28102355/determining-arterial-wave-transit-time-from-a-single-aortic-pressure-pulse-in-rats-vascular-impulse-response-analysis
#2
Ru-Wen Chang, Chun-Yi Chang, Liang-Chuan Lai, Ming-Shiou Wu, Tai-Horng Young, Yih-Sharng Chen, Chih-Hsien Wang, Kuo-Chu Chang
Arterial wave transit time (τw) in the lower body circulation is an effective biomarker of cardiovascular risk that substantially affects systolic workload imposed on the heart. This study evaluated a method for determining τw from the vascular impulse response on the basis of the measured aortic pressure and an assumed triangular flow (Q(tri)). The base of the unknown Q(tri) was constructed with a duration set equal to ejection time. The timing of the peak triangle was derived using a fourth-order derivative of the pressure waveform...
January 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28097733/optimized-amplitude-modulated-multiband-rf-pulse-design
#3
Samy Abo Seada, Anthony N Price, Joseph V Hajnal, Shaihan J Malik
PURPOSE: Multiband pulses are characterized by highly temporally modulated waveforms. Rapid phase or frequency modulation can be extremely demanding on the performance of radiofrequency (RF) pulse generation, which can lead to errors that can be avoided if pulses are restricted to amplitude modulation (AM) only. In this work, three existing multiband pulse design techniques are modified to produce AM waveforms. THEORY AND METHODS: Multiband refocusing pulses were designed using phase optimization, time shifting, and root flipping...
January 17, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28097009/statin-utilisation-in-a-real-world-setting-a-retrospective-analysis-in-relation-to-arterial-and-cardiovascular-autonomic-function
#4
John D Sluyter, Alun D Hughes, Andrew Lowe, Carlos A Camargo, Robert K R Scragg
Randomized trials suggest that statin treatment may lower blood pressure and influence cardiovascular autonomic function (CVAF), but the impact of duration of usage, discontinuation, and adherence to this therapy is unknown. We examined these issues with regard to blood pressure (BP)-related variables in a large, population-based study. Participants were 4942 adults (58% male; aged 50-84 years): 2179 on statin treatment and 2763 untreated. Days of utilization, adherence (proportion of days covered ≥0.8), and discontinuation (non-use for ≥30 days immediately prior to BP measurement) of three statins (atorvastatin, pravastatin, and simvastatin) over a period of up to 2 years was monitored retrospectively from electronic databases...
December 2016: Pharmacology Research & Perspectives
https://www.readbyqxmd.com/read/28057900/evaluation-of-the-ureteral-jet-in-dogs-using-doppler-ultrasonography
#5
Hyunjung Oh, Seongsoo Kim, Suyeon Kim, Jeosoon Lee, Sookyung Yun, Junghee Yoon, Joohyun Jung, Mincheol Choi
Ureteral jets are caused by the forceful ejection of urine from the vesicoureteral junction into the urinary bladder. We aimed to identify distinct ureteral jets in dogs by using color Doppler ultrasonography (US), provide insight into ureteral obstruction, and facilitate the study of urodynamics and vesicoureteric sphincter function using pulsed Doppler US. Color Doppler US was applied to detect urinary flow from the right ureteral orifice in eight healthy beagles. Under anesthesia, 0.9% saline (2.5 ml/kg/h) and furosemide (0...
January 4, 2017: Journal of Veterinary Science
https://www.readbyqxmd.com/read/28054915/auditory-processing-disorder-as-the-sole-manifestation-of-a-cerebellopontine-and-internal-auditory-canal-lesion
#6
Vasiliki Vivian Iliadou, Nikos Eleftheriadis
BACKGROUND: Clinical importance of auditory processing disorder (APD) testing is often overlooked and regarded with skepticism given the challenging interpretation of results and the current growing debate of its nature and clinical entity. PURPOSE: Presentation of this case is highly educational as APD is the single clinical manifestation of a large cerebellopontine and internal auditory canal lesion. RESEARCH DESIGN: A case report. DATA COLLECTION AND ANALYSIS: The patient underwent a standard audiological evaluation with normal results...
January 2017: Journal of the American Academy of Audiology
https://www.readbyqxmd.com/read/28046993/su-g-jep4-08-external-and-internal-motion-assessments-with-amplitude-and-time-based-reconstruction-and-avect
#7
P Fogg, T Aland, M West
PURPOSE: To investigate the effects of external surrogate and tumour motion by observing the reconstructed phases and AveCT in an Amplitude and Time based 4DCT. METHODS: Based on patient motion studies, Cos6 and sinusoidal motions were simulated as external surrogate and tumour motions in a motion phantom. The diaphragm and tumour motions may or may not display the same waveform therefore the same and different waveforms were programmed into the phantom, scanned and reconstructed based on Amplitude and Time...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28006027/evidence-for-weakened-intercellular-coupling-in-the-mammalian-circadian-clock-under-long-photoperiod
#8
M Renate Buijink, Assaf Almog, Charlotte B Wit, Ori Roethler, Anneke H O Olde Engberink, Johanna H Meijer, Diego Garlaschelli, Jos H T Rohling, Stephan Michel
For animals living in temperate latitudes, seasonal changes in day length are an important cue for adaptations of their physiology and behavior to the altered environmental conditions. The suprachiasmatic nucleus (SCN) is known as the central circadian clock in mammals, but may also play an important role in adaptations to different photoperiods. The SCN receives direct light input from the retina and is able to encode day-length by approximating the waveform of the electrical activity rhythm to the duration of daylight...
2016: PloS One
https://www.readbyqxmd.com/read/27990759/the-toxicity-of-flonicamid-to-cotton-leafhopper-amrasca-biguttula-ishida-is-by-disruption-of-ingestion-an-epg-study
#9
Kaleem Tariq, Mah Noor, Elaine A Backus, Adil Hussain, Asad Ali, Wei Peng, Hongyu Zhang
BACKGROUND: The cotton leafhopper, Amrasca biguttula, is one of the most destructive pests of cotton in Asia. This species is thought to cause damage by injecting enzymatic saliva into various, presently unknown, cotton tissues and ingesting the resulting macerate. Flonicamid is a novel systemic insecticide used to control the cotton leafhopper however, its mode of action is unknown. RESULTS: The mechanism of action of flonicamid on cotton leafhopper was investigated using electropenetrography (EPG)...
December 19, 2016: Pest Management Science
https://www.readbyqxmd.com/read/27989747/chronic-postnatal-monoamine-oxidase-inhibition-affects-affiliative-behavior-in-rat-pupso
#10
Sofia Blazevic, Mirna Merkler, Dora Persic, Dubravka Hranilovic
Monoamine neurotransmitters serotonin (5-HT), dopamine (DA), and noradrenaline (NA) act as important modulators of mammalian brain development and represent neurobiological substrates of affiliative behavior reflected in rat pups as a tendency to huddle or produce ultrasonic vocalizations (USV) when separated from the nest. Monoamines are metabolized through oxidative deamination catalyzed by the mitochondrial enzyme monoamine oxidase (MAO). In this study, we examined the consequences of postnatal MAO inhibition on affiliative behavior in rat pups...
December 15, 2016: Pharmacology, Biochemistry, and Behavior
https://www.readbyqxmd.com/read/27988629/electric-organ-discharges-of-south-african-i-marcusenius-i-species-teleostei-mormyridae-and-their-effectiveness-as-indicators-of-local-species-diversity
#11
L Bernd Kramer, Pholoshi A Maake, Ofer Gon
Recent morphological and genetic studies have revealed two new species of snoutfish in South Africa, Marcusenius caudisquamatus and M. krameri, which had been confused with M. pongolensis, the South African bulldog fish. All known mormyriform fish are nocturnal and emit electric organ discharges (EODs) for communication that are characteristic for their species. This paper examines whether or not the EODs of these three closely-related South African species can be differentiated from each other. An EOD pulse of a bulldog fish consists of a head-positive phase P, followed by a head-negative phase N of short duration...
November 29, 2016: Zootaxa
https://www.readbyqxmd.com/read/27959902/characterization-of-swallowing-sound-preliminary-investigation-of-normal-subjects
#12
Tsuyoshi Honda, Takuro Baba, Keiko Fujimoto, Takaharu Goto, Kan Nagao, Masafumi Harada, Eiichi Honda, Tetsuo Ichikawa
OBJECTIVE: The purpose of this study was to characterize the swallowing sound and identify the process of sound generation during swallowing in young healthy adults. METHODS: Thirty-three healthy volunteers were enrolled and allocated into three experimental groups. In experiment 1, a microphone was attached to one of eight cervical sites in 20 subjects, participants swallowed 5 ml water, and the sound waveform was recorded. In experiment 2, 10 subjects swallowed either 0, 5, 10, or 15 ml water during audio recording...
2016: PloS One
https://www.readbyqxmd.com/read/27942525/are-long-stimulus-pulse-durations-the-answer-to-improving-spatial-resolution-in-retinal-prostheses
#13
COMMENT
Matthew A Petoe, Mohit N Shivdasani
Retinal prostheses can provide artificial vision to patients with degenerate retinae by electrically stimulating the remaining inner retinal neurons. The evoked perception is generally adequate for light localization, but of limited spatial resolution owing to the indiscriminate activation of multiple retinal cell types, leading to distortions in the perceived image. Here we present a perspective on a recent work by Weitz and colleagues who demonstrate a focal confinement of retinal ganglion cell (RGC) activation when using extended pulse durations in the stimulation waveform...
November 2016: Annals of Translational Medicine
https://www.readbyqxmd.com/read/27939722/the-effects-of-linalool-on-the-excitability-of-central-neurons-of-snail-caucasotachea-atrolabiata
#14
Jafar Vatanparast, Sara Bazleh, Mahyar Janahmadi
Linalool is a major constituent of the essential oil of several plant species and possesses several biological activities. In this work, we studied the effects of linalool on excitability of central neurons of land snail Caucasotachea atrolabiata and tried to elucidate the underlying mechanisms. The lower concentration of linalool (0.1mM) showed suppressive action on spontaneous activity and pentylenetetrazole-induced epileptiform activity. These effects were associated with elevation of the action potential threshold and reduction of action potential rising phase, supporting the inhibitory action of linalool on Na(+) channels...
February 2017: Comparative Biochemistry and Physiology. Toxicology & Pharmacology: CBP
https://www.readbyqxmd.com/read/27911759/neurotransmitter-release-can-be-stabilized-by-a-mechanism-that-prevents-voltage-changes-near-the-end-of-action-potentials-from-affecting-calcium-currents
#15
Stephen G Clarke, Matthew S Scarnati, Kenneth G Paradiso
: At chemical synapses, presynaptic action potentials (APs) activate voltage-gated calcium channels, allowing calcium to enter and trigger neurotransmitter release. The duration, peak amplitude, and shape of the AP falling phase alter calcium entry, which can affect neurotransmitter release significantly. In many neurons, APs do not immediately return to the resting potential, but instead exhibit a period of depolarization or hyperpolarization referred to as an afterpotential. We hypothesized that presynaptic afterpotentials should alter neurotransmitter release by affecting the electrical driving force for calcium entry and calcium channel gating...
November 9, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/27899247/association-of-plasma-fetuin-a-levels-with-peripheral-arterial-disease-and-lower-extremity-arterial-calcification-in-subjects-with-type-2-diabetes-mellitus
#16
Ioanna Eleftheriadou, Pinelopi Grigoropoulou, Alexander Kokkinos, Iordanis Mourouzis, Despoina Perrea, Nicholas Katsilambros, Petros P Sfikakis, Nikolaos Tentolouris
AIMS: Fetuin-A is a hepatic glycoprotein that is involved in insulin resistance and atherosclerosis. Herein we examined the association of plasma fetuin-A levels with peripheral arterial disease (PAD) in patients with type 2 diabetes mellitus (T2DM). MATERIAL AND METHODS: A total of 71 patients with T2DM and 57 non-diabetic individuals were recruited. Diagnosis of PAD was based on the absence of triphasic waveform at pedal arteries, while ankle-brachial index (ABI) was calculated...
November 12, 2016: Journal of Diabetes and its Complications
https://www.readbyqxmd.com/read/27859425/maximizing-fluid-delivered-by-bubble-free-electroosmotic-pump-with-optimum-pulse-voltage-waveform
#17
Mena E Tawfik, Francisco J Diez
In generating high electroosmotic (EO) flows for use in microfluidic pumps, a limiting factor is faradaic reactions that are more pronounced at high electric fields. These reactions lead to bubble generation at the electrodes and pump efficiency reduction. The onset of gas generation for high current density EO pumping depends on many parameters including applied voltage, working fluid, and pulse duration. The onset of gas generation can be delayed and optimized for maximum volume pumped in the minimum time possible...
November 17, 2016: Electrophoresis
https://www.readbyqxmd.com/read/27852807/mechanical-tuning-of-mammalian-sperm-behaviour-by-hyperactivation-rheology-and-substrate-adhesion-a-numerical-exploration
#18
Kenta Ishimoto, Eamonn A Gaffney
The great mammalian sperm race encounters numerous microenvironments to which sperm must adapt and a fundamental sperm response is the change in its waveform owing to both fluid rheology and capacitation, with the latter associated with a hyperactivated beat pattern. Hence, in this modelling study, we examine the effect of different flagellar waveforms for sperm behaviour near adhesive substrates, which are representative of epithelia in female tract sperm reservoirs and the zona pellucida (ZP), which surrounds the mammalian egg...
November 2016: Journal of the Royal Society, Interface
https://www.readbyqxmd.com/read/27814311/effects-of-acoustic-stimulus-duration-on-cervical-vestibular-evoked-myogenic-potentials-a-neurophysiological-and-modeling-study
#19
A Ciardo, N El Assawy, S Mauro, L Priano
OBJECTIVE: To analyze and model the effects of acoustic stimulus duration on cervical vestibular evoked myogenic potentials (cVEMPs). DESIGN: Subjects with normal hearing and no vestibular or cervical disorders were tested using 1 kHz tone bursts (TBs) of different durations to evoke cVEMPs from the ipsilateral sternocleidomastoid muscle. VEMP modeling was performed in Labview. RESULTS: The increase in TB duration initially resulted in a non-linear increase in cVEMP amplitude, followed by more complex cVEMP modifications that were mainly related to the appearance of a new wave (nX) that interfered with n23...
November 3, 2016: Journal of Vestibular Research: Equilibrium & Orientation
https://www.readbyqxmd.com/read/27812293/atrial-electrophysiological-remodeling-and-fibrillation-in-heart-failure
#20
REVIEW
Sandeep V Pandit, Antony J Workman
Heart failure (HF) causes complex, chronic changes in atrial structure and function, which can cause substantial electrophysiological remodeling and predispose the individual to atrial fibrillation (AF). Pharmacological treatments for preventing AF in patients with HF are limited. Improved understanding of the atrial electrical and ionic/molecular mechanisms that promote AF in these patients could lead to the identification of novel therapeutic targets. Animal models of HF have identified numerous changes in atrial ion currents, intracellular calcium handling, action potential waveform and conduction, as well as expression and signaling of associated proteins...
2016: Clinical Medicine Insights. Cardiology
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