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https://www.readbyqxmd.com/read/28791908/synthesis-and-biological-evaluation-of-novel-7-hydroxy-4-phenylchromen-2-one-linked-to-triazole-moieties-as-potent-cytotoxic-agents
#1
Chuan-Feng Liu, Qing-Kun Shen, Jia-Jun Li, Yu-Shun Tian, Zheshan Quan
A new series of novel 7-hydroxy-4-phenylchromen-2-one (1a)-linked 1,2,4-triazoles were synthesised using a click chemistry approach. All derivatives were subjected to 3-(4,5-dimethylthiazol-yl)-diphenyl tetrazolium bromide (MTT) cytotoxicity screening against a panel of six different human cancer cell lines (AGS, MGC-803, HCT-116, A-549, HepG2, and HeLa) to assess their cytotoxic potential. Among the tested molecules, some of the analogues showed better cytotoxic activity than that shown by the 7-hydroxy-4-phenylchromen-2-one (1a)...
December 2017: Journal of Enzyme Inhibition and Medicinal Chemistry
https://www.readbyqxmd.com/read/28783626/fast-and-fully-automatic-left-ventricular-segmentation-and-tracking-in-echocardiography-using-shape-based-b-spline-explicit-active-surfaces
#2
Joao Pedrosa, Sandro Queiros, Olivier Bernard, Jan Engvall, Thor Edvardsen, Eike Nagel, Jan Dhooge
Cardiac volume/function assessment remains a critical step in daily cardiology and 3D ultrasound plays an increasingly important role. Fully automatic left ventricular segmentation is, however, a challenging task due to the artifacts and low contrast-to-noise ratio of ultrasound imaging. In the present work, a fast and fully automatic framework for full cycle endocardial left ventricle segmentation is proposed. This approach couples the advantages of the B-spline explicit active surfaces framework, a purely image information approach, to those of statistical shape models to give prior information about the expected shape for an accurate segmentation...
August 2, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28766919/turbulent-kinetic-energy-in-the-right-ventricle-potential-mr-marker-for-risk-stratification-of-adults-with-repaired-tetralogy-of-fallot
#3
Alexandru Fredriksson, Aleksandra Trzebiatowska-Krzynska, Petter Dyverfeldt, Jan Engvall, Tino Ebbers, Carl-Johan Carlhäll
PURPOSE: To assess right ventricular (RV) turbulent kinetic energy (TKE) in patients with repaired Tetralogy of Fallot (rToF) and a spectrum of pulmonary regurgitation (PR), as well as to investigate the relationship between these 4D flow markers and RV remodeling. MATERIALS AND METHODS: Seventeen patients with rToF and 10 healthy controls were included in the study. Patients were divided into two groups based on PR fraction: one lower PR fraction group (≤11%) and one higher PR fraction group (>11%)...
August 2, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28765192/four-dimensional-ct-guided-transcatheter-removal-of-a-fractured-migrated-catheter-of-a-totally-implantable-venous-access-port
#4
Kazushi Fujimoto, Hajime Kasai, Toshihiko Sugiura, Koichiro Tatsumi
Patients undergoing chemotherapy usually undergo placement of a totally implantable venous access port (TIVAP), but TIVAP catheter fracture is rare. We encountered a case where flushing the TIVAP catheter became impossible because of resistance. A 61-year-old-woman underwent TIVAP placement. Although a chest X-ray revealed the fractured catheter had migrated into the right hilar area, the timing of the fracture was unclear. Four-dimensional computed tomography (4D-CT) showed that the tip of the fractured catheter was located at the anterior segmental artery of the right upper lobe and was immobile, with the remaining portion flapping with the blood flow...
August 1, 2017: BMJ Case Reports
https://www.readbyqxmd.com/read/28747663/four-dimensional-material-movies-high-speed-phase-contrast-tomography-by-backprojection-along-dynamically-curved-paths
#5
A Ruhlandt, M Töpperwien, M Krenkel, R Mokso, T Salditt
We present an approach towards four dimensional (4d) movies of materials, showing dynamic processes within the entire 3d structure. The method is based on tomographic reconstruction on dynamically curved paths using a motion model estimated by optical flow techniques, considerably reducing the typical motion artefacts of dynamic tomography. At the same time we exploit x-ray phase contrast based on free propagation to enhance the signal from micron scale structure recorded with illumination times down to a millisecond (ms)...
July 26, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28745409/assessment-of-reynolds-stress-components-and-turbulent-pressure-loss-using-4d-flow-mri-with-extended-motion-encoding
#6
Henrik Haraldsson, Sarah Kefayati, Sinyeob Ahn, Petter Dyverfeldt, Jonas Lantz, Matts Karlsson, Gerhard Laub, Tino Ebbers, David Saloner
PURPOSE: To measure the Reynolds stress tensor using 4D flow MRI, and to evaluate its contribution to computed pressure maps. METHODS: A method to assess both velocity and Reynolds stress using 4D flow MRI is presented and evaluated. The Reynolds stress is compared by cross-sectional integrals of the Reynolds stress invariants. Pressure maps are computed using the pressure Poisson equation-both including and neglecting the Reynolds stress. RESULT: Good agreement is seen for Reynolds stress between computational fluid dynamics, simulated MRI, and MRI experiment...
July 26, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28744840/organ-dynamics-and-fluid-dynamics-of-the-hh25-chick-embryonic-cardiac-ventricle-as-revealed-by-a-novel-4d-high-frequency-ultrasound-imaging-technique-and-computational-flow-simulations
#7
Sheldon Ho, Germaine Xin Yi Tan, Toon Jin Foo, Nhan Phan-Thien, Choon Hwai Yap
Past literature has provided evidence that a normal mechanical force environment of blood flow may guide normal development while an abnormal environment can lead to congenital malformations, thus warranting further studies on embryonic cardiovascular flow dynamics. In the current study, we developed a non-invasive 4D high-frequency ultrasound technique, and use it to analyze cardiovascular organ dynamics and flow dynamics. Three chick embryos at stage HH25 were scanned with high frequency ultrasound in cine-B-mode at multiple planes spaced at 0...
July 25, 2017: Annals of Biomedical Engineering
https://www.readbyqxmd.com/read/28742031/patient-specific-left-ventricular-flow-simulations-from-transthoracic-echocardiography-robustness-evaluation-and-validation-against-ultrasound-doppler-and-magnetic-resonance-imaging
#8
David Larsson, Jeannette H Spuhler, Sven Petersson, Tim Nordenfur, Massimiliano Colarieti-Tosti, Johan Hoffman, Reidar Winter, Matilda Larsson
The combination of medical imaging with computational fluid dynamics (CFD) has enabled the study of 3D blood flow on a patient-specific level. However, with models based on gated high-resolution data, the study of transient flows, and any model implementation into routine cardiac care, is challenging. The present paper presents a novel pathway for patient-specific CFD modelling of the left ventricle (LV), using 4D transthoracic echocardiography (TTE) as input modality. To evaluate the clinical usability, two sub-studies were performed...
July 21, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28721492/peristaltic-like-motion-of-the-human-fetal-right-ventricle-and-its-effects-on-fluid-dynamics-and-energy-dynamics
#9
Hadi Wiputra, Guat Ling Lim, Khong Chun Chua, R Nivetha, Sanah Merchant Soomar, Arijit Biwas, Citra Nurfarah Zaini Mattar, Hwa Liang Leo, Choon Hwai Yap
In both adult human and canine, the cardiac right ventricle (RV) is known to exhibit a peristaltic-like motion, where RV sinus (inflow region) contracts first and the infundibulum (outflow region) later, in a wave-like contraction motion. The delay in contraction between the sinus and infundibulum averaged at 15% of the cardiac cycle and was estimated to produce an intra-ventricular pressure difference of 15 mmHg. However, whether such a contractile motion occurs in human fetuses as well, its effects on hemodynamics remains unknown, and are the subject of the current study...
July 18, 2017: Annals of Biomedical Engineering
https://www.readbyqxmd.com/read/28714282/variability-of-4d-flow-parameters-when-subjected-to-changes-in-mri-acquisition-parameters-using-a-realistic-thoracic-aortic-phantom
#10
Cristian Montalba, Jesus Urbina, Julio Sotelo, Marcelo E Andia, Cristian Tejos, Pablo Irarrazaval, Daniel E Hurtado, Israel Valverde, Sergio Uribe
PURPOSE: To assess the variability of peak flow, mean velocity, stroke volume, and wall shear stress measurements derived from 3D cine phase contrast (4D flow) sequences under different conditions of spatial and temporal resolutions. METHODS: We performed controlled experiments using a thoracic aortic phantom. The phantom was connected to a pulsatile flow pump, which simulated nine physiological conditions. For each condition, 4D flow data were acquired with different spatial and temporal resolutions...
July 16, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28711164/on-estimating-intraventricular-hemodynamic-forces-from-endocardial-dynamics-a-comparative-study-with-4d-flow-mri
#11
Gianni Pedrizzetti, Per M Arvidsson, Johannes Töger, Rasmus Borgquist, Federico Domenichini, Håkan Arheden, Einar Heiberg
Intraventricular pressure gradients or hemodynamic forces, which are their global measure integrated over the left ventricular volume, have a fundamental importance in ventricular function. They may help revealing a sub-optimal cardiac function that is not evident in terms of tissue motion, which is naturally heterogeneous and variable, and can influence cardiac adaptation. However, hemodynamic forces are not utilized in clinical cardiology due to the unavailability of simple non-invasive measurement tools...
July 5, 2017: Journal of Biomechanics
https://www.readbyqxmd.com/read/28710578/four-dimensional-flow-mri-of-stented-versus-stentless-aortic-valve-bioprostheses
#12
Floortje van Kesteren, Laurens W Wollersheim, Jan Baan, Aart J Nederveen, Abdullah Kaya, S Matthijs Boekholdt, Bas A de Mol, Pim van Ooij, R Nils Planken
OBJECTIVES: To evaluate aortic velocity, wall shear stress (WSS) and viscous energy loss (EL) of stented and stentless bioprostheses using 4D flow MRI 1 year after surgical aortic valve replacement. METHODS: For this cross-sectional study 28 patients with stented (n = 14) or stentless (n = 14) bioprosthesis underwent non-contrast-enhanced 4D-flow MRI at 1.5 T. Analyses included a comparison of velocity, WSS and EL in the ascending aorta during peak systole for both spatially averaged values and a comparison of local differences using per-voxel analysis...
July 14, 2017: European Radiology
https://www.readbyqxmd.com/read/28710184/diagnostic-value-of-four-dimensional-ct-angiography-in-arterial-erectile-dysfunction-using-320-detector-row-dynamic-volume-ct
#13
Cheng-Cheng Xu, Xin-Zhong Ruan, Yi-Fan Tang, Jiao-Hai Pan, Guo-Yao Wang, Qiu-Li Huang
The study aims to evaluate the diagnostic value of four-dimensional CT angiography (4D-CTA) in the diagnosis of arterial erectile dysfunction (ED) using 320-detector row dynamic volume CT. Arterial ED patients attributed to arterial insufficiency were enrolled. To induce penile erection, an intracavernous injection of corpus cavernosum with a vasoactive drug was administered. Patients were assigned into the erection hardness score (EHS) 1/2 group or EHS 3/4 group. Color duplex Doppler ultrasound (CDDU) was used to analyze blood flow spectrum...
July 14, 2017: Bioscience Reports
https://www.readbyqxmd.com/read/28699611/impact-of-high-flow-nasal-cannula-therapy-in-quality-%C3%A4-mprovement-and-clinical-outcomes-in-a-non-invasive-ventilation-device-free-pediatric-%C3%A4-ntensive-care-unit
#14
Fulva Kamit Can, Ayse Berna Anil, Murat Anil, Neslihan Zengin, Alkan Bal, Yuksel Bicilioglu, Gamze Gokalp, Fatih Durak, Gulberat Ince
OBJECTIVE: To analyze the change in quality indicators due to the use of high-flow nasal cannula therapy as a non-invasive ventilation method in children with respiratory distress/failure in a noninvasive ventilation device-free pediatric intensive care unit. METHODS: The study was a retrospective chart review of children with respiratory distress/failure admitted 1 year before (period before high-flow nasal cannula therapy) and 1 year after (period after high-flow nasal cannula therapy) the introduction of high-flow nasal cannula therapy...
July 11, 2017: Indian Pediatrics
https://www.readbyqxmd.com/read/28694784/4d-flow-analysis-of-bav-related-fluid-dynamic-alterations-evidences-of-wall-shear-stress-alterations-in-absence-of-clinically-relevant-aortic-anatomical-remodeling
#15
Filippo Piatti, Francesco Sturla, Malenka M Bissell, Selene Pirola, Massimo Lombardi, Igor Nesteruk, Alessandro Della Corte, Alberto C L Redaelli, Emiliano Votta
Bicuspid aortic valve (BAV) is the most common congenital cardiac disease and is a foremost risk factor for aortopathies. Despite the genetic basis of BAV and of the associated aortopathies, BAV-related alterations in aortic fluid-dynamics, and particularly in wall shear stresses (WSSs), likely play a role in the progression of aortopathy, and may contribute to its pathogenesis. To test whether WSS may trigger aortopathy, in this study we used 4D Flow sequences of phase-contrast cardiac magnetic resonance imaging (CMR) to quantitatively compare the in vivo fluid dynamics in the thoracic aorta of two groups of subjects: (i) five prospectively enrolled young patients with normo-functional BAV and with no aortic dilation and (ii) ten age-matched healthy volunteers...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28688629/directional-analysis-of-cardiac-motion-field-from-gated-fluorodeoxyglucose-pet-images-using-the-discrete-helmholtz-hodge-decomposition
#16
J A Sims, M C Giorgi, M A Oliveira, J C Meneghetti, M A Gutierrez
OBJECTIVES: Extract directional information related to left ventricular (LV) rotation and torsion from a 4D PET motion field using the Discrete Helmholtz Hodge Decomposition (DHHD). MATERIALS AND METHODS: Synthetic motion fields were created using superposition of rotational and radial field components and cardiac fields produced using optical flow from a control and patient image. These were decomposed into curl-free (CF) and divergence-free (DF) components using the DHHD...
June 29, 2017: Computerized Medical Imaging and Graphics: the Official Journal of the Computerized Medical Imaging Society
https://www.readbyqxmd.com/read/28656461/comparison-of-radial-4d-flow-mri-with-perivascular-ultrasound-to-quantify-blood-flow-in-the-abdomen-and-introduction-of-a-porcine-model-of-pre-hepatic-portal-hypertension
#17
A Frydrychowicz, A Roldan-Alzate, E Winslow, D Consigny, C A Campo, U Motosugi, K M Johnson, O Wieben, S B Reeder
OBJECTIVES: Objectives of this study were to compare radial time-resolved phase contrast magnetic resonance imaging (4D Flow-MRI) with perivascular ultrasound (pvUS) and to explore a porcine model of acute pre-hepatic portal hypertension (PHTN). METHODS: Abdominal 4D Flow-MRI and pvUS in portal and splenic vein, hepatic and both renal arteries were performed in 13 pigs of approximately 60 kg. In six pigs, measurements were repeated after partial portal vein (PV) ligature...
June 27, 2017: European Radiology
https://www.readbyqxmd.com/read/28645326/improving-visualization-of-4d-flow-cardiovascular-magnetic-resonance-with-four-dimensional-angiographic-data-generation-of-a-4d-phase-contrast-magnetic-resonance-cardioangiography-4d-pc-mrca
#18
Mariana Bustamante, Vikas Gupta, Carl-Johan Carlhäll, Tino Ebbers
Magnetic Resonance Angiography (MRA) and Phase-Contrast MRA (PC-MRA) approaches used for assessment of cardiovascular morphology typically result in data containing information from the entire cardiac cycle combined into one 2D or 3D image. Information specific to each timeframe of the cardiac cycle is, however, lost in this process. This study proposes a novel technique, called Phase-Contrast Magnetic Resonance CardioAngiography (4D PC-MRCA), that utilizes the full potential of 4D Flow CMR when generating temporally resolved PC-MRA data to improve visualization of the heart and major vessels throughout the cardiac cycle...
June 23, 2017: Journal of Cardiovascular Magnetic Resonance
https://www.readbyqxmd.com/read/28640394/in-scan-and-scan-rescan-assessment-of-lv-in-and-outflow-volumes-by-4d-flow-mri-versus-2d-planimetry
#19
Vivian P Kamphuis, Roel L F van der Palen, Patrick J H de Koning, Mohammed S M Elbaz, Rob J van der Geest, Albert de Roos, Arno A W Roest, Jos J M Westenberg
PURPOSE: To evaluate the in-scan and scan-rescan consistency of left ventricular (LV) in- and outflow assessment from 1) 2D planimetry; 2) 4D flow magnetic resonance imaging (MRI) with retrospective valve tracking, and 3) 4D flow MRI with particle tracing. MATERIALS AND METHODS: Ten healthy volunteers (age 27 ± 3 years) underwent multislice cine short-axis planimetry and whole-heart 4D flow MRI on a 3T MRI scanner twice with repositioning between the scans...
June 22, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28624566/4d-phase-contrast-mri-protocol-optimization-using-patient-specific-3d-printed-replicas-for-in-vivo-imaging-before-and-after-flow-diverter-placement
#20
Christof Karmonik, Jeff R Anderson, Saba Elias, Richard Klucznik, Orlando Diaz, Y Jonathan Zhang, Robert G Grossman, Gavin W Britz
PURPOSE: Hemodynamics in cerebral aneurysms is currently investigated towards its clinical efficacy using non-standardized computational simulation techniques. At the same time, flow patterns and velocities are accessible by 4D phase contrast magnetic resonance imaging (4D pcMRI). Complexity of protocol design and imaging duration has limited the use of this technique in clinical imaging. A new approach is presented to overcome these limitations. MATERIAL AND METHODS: 3D replicas of two cerebral aneurysms were fabricated by fused deposition prototyping (3D printing) and imaged using 4D pcMRI while connected to an MRI compatible continuous flow loop...
June 14, 2017: World Neurosurgery
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