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https://www.readbyqxmd.com/read/27885445/limited-ventricular-preload-is-the-main-reason-for-reduced-stress-reserve-after-atrial-baffle-repair
#1
Andreas Eicken, Julia Michel, Alfred Hager, Daniel Tanase, Harald Kaemmerer, Julie Cleuziou, John Hess, Peter Ewert
The atrial baffle repair (ABR) significantly improved the fate of patients with transposition of the great arteries (TGA). However, these patients show impaired exercise tolerance and some present severe decline of systemic ventricular function. Intrinsic myocardial weakness, low heart rate response to exercise and diastolic filling impairment are discussed to be causative. Forty-nine long-term survivors with TGA (median age 23.7 year) after ABR were catheterized with measured oxygen consumption in four conditions (baseline, volume, atrial pacing, dobutamine) and the results were compared to 10 normal controls...
November 24, 2016: Pediatric Cardiology
https://www.readbyqxmd.com/read/27816583/magneto-controlled-aptasensor-for-simultaneous-electrochemical-detection-of-dual-mycotoxins-in-maize-using-metal-sulfide-quantum-dots-coated-silica-as-labels
#2
Chengquan Wang, Jing Qian, Keqi An, Xingyi Huang, Lufang Zhao, Qian Liu, Nan Hao, Kun Wang
Currently there is an urgent need for multi-mycotoxin detection methods due to the co-occurrence of multiple mycotoxins in food raw materials and their augmented toxicity. Herein, a magneto-controlled aptasensor has been developed for simultaneous electrochemical detection of ochratoxin A (OTA) and fumonisin B1 (FB1), two typical mycotoxins found in food crops world-wide. This aptasensor was designed using the high specificity between the target and aptamer with heavy CdTe or PbS quantum dots (QDs) coated silica as labels and the complementary DNA functionalized magnetic beads as capture probes...
October 4, 2016: Biosensors & Bioelectronics
https://www.readbyqxmd.com/read/27754006/js-ish-esh-2-update-on-the-detection-and-follow-up-of-early-hypertensive-heart-disease
#3
Enrico Agabiti Rosei
Current Hypertension Guidelines emphasize the importance of assessing the presence of preclinical organ damage. In fact, an extensive evaluation of organ damage may increase the number of patients classified at high CV risk and therefore strongly influence the clinical management of patients. Hypertensive heart disease remains to date the form of organ damage for which there is the greatest amount of evidence of a strong independent prognostic significance. In the presence of a chronic pressure overload, a parallel addition of sarcomers takes place with an increase in myocyte width, which in turn increases left ventricular wall thickness; myocyte hypertrophy is also associated with apoptosis, collagen deposition and ventricular fibrosis with an impairment of coronary hemodynamics as well, thus profoundly influencing functional properties of the left (and right) ventricle...
September 2016: Journal of Hypertension
https://www.readbyqxmd.com/read/27744267/ventricular-vascular-dynamics-in-pediatric-patients-with-heart-failure-and-preserved-ejection-fraction
#4
Satoshi Masutani, Seiko Kuwata, Clara Kurishima, Yoichi Iwamoto, Hirofumi Saiki, Masaya Sugimoto, Hirotaka Ishido, Hideaki Senzaki
OBJECTIVE: The details of the ventricular-vascular dynamics of heart failure with preserved ejection fraction (HFpEF) in children remain poorly understood. We tested the hypothesis that pediatric HFpEF patients have ventricular systolic, diastolic, and arterial stiffening at rest as well as impaired reserve function associated with coronary supply/demand imbalance. METHODS: We studied the ventricular pressure-area relationship in 22 pediatric HFpEF patients and 22 control subjects before and after dobutamine infusion and during abdominal compression...
September 30, 2016: International Journal of Cardiology
https://www.readbyqxmd.com/read/27642917/js-ish-esh-2-update-on-the-detection-and-follow-up-of-early-hypertensive-heart-disease
#5
Enrico Agabiti Rosei
Current Hypertension Guidelines emphasize the importance of assessing the presence of preclinical organ damage. In fact, an extensive evaluation of organ damage may increase the number of patients classified at high CV risk and therefore strongly influence the clinical management of patients. Hypertensive heart disease remains to date the form of organ damage for which there is the greatest amount of evidence of a strong independent prognostic significance. In the presence of a chronic pressure overload, a parallel addition of sarcomers takes place with an increase in myocyte width, which in turn increases left ventricular wall thickness; myocyte hypertrophy is also associated with apoptosis, collagen deposition and ventricular fibrosis with an impairment of coronary hemodynamics as well, thus profoundly influencing functional properties of the left (and right) ventricle...
September 2016: Journal of Hypertension
https://www.readbyqxmd.com/read/27564375/quantification-of-the-fungal-fraction-released-from-various-preloaded-fibrous-filters-during-a-simulated-ventilation-restart
#6
K Morisseau, A Joubert, L Le Coq, Y Andres
This study aimed to demonstrate that particles, especially those associated with fungi, could be released from fibrous filters used in the air-handling unit (AHU) of heating, ventilation and air-conditioning (HVAC) systems during ventilation restarts. Quantification of the water retention capacity and SEM pictures of the filters was used to show the potential for fungal proliferation in unused or preloaded filters. Five fibrous filters with various particle collection efficiencies were studied: classes G4, M5, M6, F7, and combined F7 according to European standard EN779:2012...
August 26, 2016: Indoor Air
https://www.readbyqxmd.com/read/27553928/acute-effect-of-static-exercise-in-patients-with-aortic-regurgitation-assessed-by-cardiovascular-magnetic-resonance-role-of-left-ventricular-remodelling
#7
Josep M Alegret, Neus Martinez-Micaelo, Andre La Gerche, Luis Franco-Bonafonte, Francisco Rubio-Pérez, Nahum Calvo, Manuel Montero
OBJECTIVE: In patients with aortic regurgitation (AR), the effect of static exercise (SE) on global ventricular function and AR severity has not been previously studied. METHODS: Resting and SE cardiovascular magnetic resonance (CMR) were prospectively performed in 23 asymptomatic patients with AR. RESULTS: During SE, we observed a decrease in regurgitant volume in both end-diastolic (EDV) and end-systolic (ESV) volume in both ventricles, as well as a slight decrease in LV ejection fraction (EF)...
August 23, 2016: European Radiology
https://www.readbyqxmd.com/read/27473939/right-ventricular-end-diastolic-stiffness-heralds-right-ventricular-failure-in-monocrotaline-induced-pulmonary-hypertension
#8
Mohamed Alaa, Mahmoud Abdellatif, Marta Tavares-Silva, José Oliveira-Pinto, Lucas Lopes, Sara Leite, Adelino F Leite-Moreira, André P Lourenço
Recent studies suggest right ventricular (RV) stiffness is important in pulmonary hypertension (PH) prognosis. Smaller stroke volume (SV) variation after a certain RV end-diastolic pressure (EDP) respiratory variation as assessed by spectral transfer function (STF) may identify RV stiffness. Our aim was to evaluate RV stiffness in monocrotaline (MCT)-induced PH progression and to validate STF gain between EDP and SV as marker of stiffness. Seven-week-old male Wistar rats randomly injected with 60 mg/kg MCT or vehicle were divided into three groups (n = 12 each) according to cardiac index (CI): controls (Ctrl), preserved CI (MCT pCI), and reduced CI (MCT rCI)...
October 1, 2016: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/27344674/left-atrial-dysfunction-in-end-stage-renal-disease-patients-treated-by-hemodialysis
#9
Jan Malik, Jana Lachmanova, Jaroslav Kudlicka, Katarina Rocinova, Anna Valerianova, Magdalena Bartkova, Vladimir Tesar
BACKGROUND: Repeated inter-dialysis water retention contributes to the development of left ventricular hypertrophy and failure, which is responsible for significant mortality of end-stage renal disease (ESRD) patients. The left atrium has a thin wall, which makes it even more prone to preload changes. In the general population with heart failure with preserved ejection fraction (HFpEF), left atrial function is even worse than that in patients with reduced ejection fraction. We hypothesized that repeated water retention is related to left atrial dysfunction in ESRD patients treated by hemodialysis and that the expected changes would be related to the brain natriuretic peptide (BNP) levels...
2016: Nephron
https://www.readbyqxmd.com/read/27308858/static-and-functional-hemodynamic-profiles-of-women-with-abnormal-uterine-artery-doppler-at-22-24-weeks-of-gestation
#10
Åse Vårtun, Kari Flo, Christian Widnes, Ganesh Acharya
OBJECTIVE: To compare cardiac function, systemic hemodynamics and preload reserve of women with increased (cases) and normal (controls) uterine artery (UtA) pulsatility index (PI) at 22-24 weeks of gestation. MATERIALS AND METHODS: A prospective cross-sectional study of 620 pregnant women. UtA blood flow velocities were measured using Doppler ultrasonography, and PI was calculated. Mean UtA PI ≥ 1.16 (90th percentile) was considered abnormal. Maternal hemodynamics was investigated at baseline and during passive leg raising (PLR) using impedance cardiography (ICG)...
2016: PloS One
https://www.readbyqxmd.com/read/27291789/effect-of-degeneration-on-the-six-degree-of-freedom-mechanical-properties-of-human-lumbar-spine-segments
#11
Dhara B Amin, Dana Sommerfeld, Isaac M Lawless, Richard M Stanley, Boyin Ding, John J Costi
While the effects of disc degeneration on compression and rotation motions have been studied, there is no data for shear loading. Clinical research has shown that those with low back pain (a potential consequence of degeneration) experience a 75% greater lateral shear force than those without it. Therefore, the aim was to compare the effect of degeneration on spine segment stiffness and phase angle in each of six degree of freedom (6DOF) loading directions. Fourteen intact functional spinal units (FSU) were dissected from human lumbar spines (mean (SD) age 76...
August 2016: Journal of Orthopaedic Research: Official Publication of the Orthopaedic Research Society
https://www.readbyqxmd.com/read/27273159/an-all-in-one-tympanostomy-tube-insertion-device-results-of-usability-testing-in-fourteen-cadaveric-and-twelve-plastic-model-ears
#12
Rachael Lawrence, Paddy McGowan, Matija Daniel
1.The All-In-One Tympanostomy tube (TT) insertion device with its preloaded tympanostomy tube allows a safe, intuitive and rapid myringotomy and TT insertion. 2.In plastic ear models, the TT was successfully inserted into the tympanic membrane in all cases. 3.In cadavers, TT insertion was successful in all 14 ears, but with one premature deployment. 4.The all-in-one TT device has the potential to be used without the requirement for General Anaesthesia (GA) in appropriately selected adults and children. 5.The all-in-one TT device could reduce waiting times and costs...
June 7, 2016: Clinical Otolaryngology
https://www.readbyqxmd.com/read/27256450/a-novel-set-up-for-the-ex-vivo-analysis-of-mechanical-properties-of-mouse-aortic-segments-stretched-at-physiological-pressure-and-frequency
#13
Arthur J A Leloup, Cor E Van Hove, Ammar Kurdi, Sofie De Moudt, Wim Martinet, Guido R Y De Meyer, Dorien M Schrijvers, Gilles W De Keulenaer, Paul Fransen
KEY POINTS: Cyclic stretch is known to alter intracellular pathways involved in vessel tone regulation. We developed a novel set-up that allows straightforward characterization of the biomechanical properties of the mouse aorta while stretched at a physiological heart rate (600 beats min(-1) ). Active vessel tone was shown to have surprisingly large effects on isobaric stiffness. The effect of structural vessel wall alterations was confirmed using a genetic mouse model. This set-up will contribute to a better understanding of how active vessel wall components and mechanical stimuli such as stretch frequency and amplitude regulate aortic mechanics...
November 1, 2016: Journal of Physiology
https://www.readbyqxmd.com/read/27219461/lymphatic-pumping-mechanics-mechanisms-and-malfunction
#14
Joshua P Scallan, Scott D Zawieja, Jorge A Castorena-Gonzalez, Michael J Davis
A combination of extrinsic (passive) and intrinsic (active) forces move lymph against a hydrostatic pressure gradient in most regions of the body. The effectiveness of the lymph pump system impacts not only interstitial fluid balance but other aspects of overall homeostasis. This review focuses on the mechanisms that regulate the intrinsic, active contractions of collecting lymphatic vessels in relation to their ability to actively transport lymph. Lymph propulsion requires not only robust contractions of lymphatic muscle cells, but contraction waves that are synchronized over the length of a lymphangion as well as properly functioning intraluminal valves...
October 15, 2016: Journal of Physiology
https://www.readbyqxmd.com/read/27151565/beat-to-beat-variability-in-preload-unmasks-latent-risk-of-torsade-de-pointes-in-anesthetized-chronic-atrioventricular-block-dogs
#15
Thom Rg Stams, Peter Oosterhoff, Atty Heijdel, Albert Dunnink, Jet Dm Beekman, Roel van der Nagel, Harold Vm van Rijen, Marcel Ag van der Heyden, Marc A Vos
BACKGROUND: Beat-to-beat variability in ventricular repolarization (BVR) associates with increased arrhythmic risk. Proarrhythmic remodeling in the dog with chronic AV-block (CAVB) compromises repolarization reserve and associates with increased BVR, which further increases upon dofetilide infusion and correlates with Torsade de Pointes (TdP) arrhythmias. It was hypothesized that these pro-arrhythmia-associated increases in BVR are induced by beat-to-beat variability in preload. METHODS AND RESULTS: Left ventricular monophasic action potential duration (LVMAPD) was recorded in acute (AAVB) and CAVB dogs, before and after dofetilide infusion...
May 25, 2016: Circulation Journal: Official Journal of the Japanese Circulation Society
https://www.readbyqxmd.com/read/27101363/optimizing-the-circulation-in-the-prone-patient
#16
Mathieu Jozwiak, Xavier Monnet, Jean-Louis Teboul
PURPOSE OF REVIEW: Prone positioning is recommended as a rescue therapy to improve arterial oxygenation in patients with severe acute respiratory distress syndrome (ARDS). In this review, we summarize the macro and the microcirculatory effects of prone positioning and emphasize which hemodynamic variables can be monitored when this therapy is applied. RECENT FINDINGS: Early and prolonged prone positioning sessions significantly decrease the mortality of patients with severe ARDS...
June 2016: Current Opinion in Critical Care
https://www.readbyqxmd.com/read/27013347/differential-impact-of-genetically-modulated-choline-transporter-expression-on-the-release-of-endogenous-versus-newly-synthesized-acetylcholine
#17
Hideki Iwamoto, M Wade Calcutt, Randy D Blakely
The efficient import of choline into cholinergic nerve terminals by the presynaptic, high-affinity choline transporter (CHT, SLC5A7) dictates the capacity for acetylcholine (ACh) synthesis and release. Tissue levels of ACh are significantly reduced in mice heterozygous for a loss of function mutation in Slc5a7 (HET, CHT(+/-)), but significantly elevated in overexpressing, Slc5a7 BAC-transgenic mice (BAC). Since the readily-releasable pool of ACh is thought to constitute a small fraction of the total ACh pool, these genotype-dependent changes raised the question as to whether CHT expression or activity might preferentially influence the size of reserve pool ACh vesicles...
September 2016: Neurochemistry International
https://www.readbyqxmd.com/read/26990567/effects-of-motion-segment-level-pfirrmann-intervertebral-disc-degeneration-grade-and-gender-on-lumbar-spine-kinematics
#18
Muturi G Muriuki, Robert M Havey, Leonard I Voronov, Gerard Carandang, Michael R Zindrick, Mark A Lorenz, Laurie Lomasney, Avinash G Patwardhan
MRI allows non-invasive assessment of intervertebral disc degeneration with the added clinical benefit of using non-ionizing radiation. What has remained unclear is the relationship between assessed disc degeneration and lumbar spine kinematics. Kinematic outcomes of 54 multi-segment (L1-Sacrum) lumbar spine specimens were calculated to discover if such an underlying relationship exists with degeneration assessed using the Pfirrmann grading system. Further analyses were also conducted to determine if kinematic outcomes were affected by motion segment level, gender or applied compressive preload...
August 2016: Journal of Orthopaedic Research: Official Publication of the Orthopaedic Research Society
https://www.readbyqxmd.com/read/26967137/the-high-cost-of-motherhood-end-lactation-syndrome-in-southern-sea-otters-enhydra-lutris-nereis-on-the-central-california-coast-usa
#19
Sarah M Chinn, Melissa A Miller, M Tim Tinker, Michelle M Staedler, Francesca I Batac, Erin M Dodd, Laird A Henkel
Sea otters ( Enhydra lutris ) have exceptionally high energetic requirements, which nearly double during lactation and pup care. Thus, females are extremely vulnerable to caloric insufficiency. Despite a number of compensatory strategies, the metabolic challenge of reproduction culminates in numerous maternal deaths annually. Massive depletion of energy reserves results in a case presentation that we define as end-lactation syndrome (ELS), characterized by moderate to severe emaciation not attributable to a concurrent, independent disease process in females dying during late pup care or postweaning...
April 28, 2016: Journal of Wildlife Diseases
https://www.readbyqxmd.com/read/26946331/ductus-venosus-doppler-in-the-assessment-of-fetal-cardiovascular-health-an-updated-practical-approach
#20
REVIEW
Viola Seravalli, Jena L Miller, Dana Block-Abraham, Ahmet A Baschat
The ductus venosus has a central role in the distribution of highly oxygenated umbilical venous blood to the heart. Its waveform is related to the pressure-volume changes in the cardiac atria and it is therefore important in the monitoring of any fetal condition that may affect forward cardiac function. The cardiovascular parameters that can influence forward cardiac function include afterload, myocardial performance and preload. Decreased forward flow during atrial systole (a-wave) is the most sensitive and ubiquitous finding when any of these parameters is affected...
June 2016: Acta Obstetricia et Gynecologica Scandinavica
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