Read by QxMD icon Read

coronary and Kv

Hidenari Matsumoto, Satoshi Watanabe, Eisho Kyo, Takafumi Tsuji, Yosuke Ando, Yuka Otaki, Sebastien Cadet, Piotr J Slomka, Daniel S Berman, Damini Dey, Balaji K Tamarappoo
BACKGROUND: It has been shown that CT attenuation of noncalcified plaques depends on luminal contrast attenuation (LCA). Although tube potential (kilovolt [kV]) has been shown to exert influence on plaque attenuation through LCA as well as its direct effects, in-vivo studies have not investigated plaque attenuation at lower tube potentials less than 120 kV. We sought to evaluate the effect of kV and LCA on thresholds for lipid-rich and fibrous plaques as defined by intravascular ultrasound (IVUS)...
February 12, 2019: Journal of Cardiovascular Computed Tomography
Weiping Li, Miaomiao Dong, Pengmei Guo, Yu Liu, Yixin Jing, Rui Chen, Mingsheng Zhang
AIMS: Luteolin has been shown to be beneficial to cardiovascular tissues and organs. We aimed to study its vasospasmolytic effects against various vasoconstrictors in the isolated rat coronary arteries (RCAs) and its electrophysiological effects on K+ currents via voltage-gated potassium (Kv) channels and inward rectifier potassium (Kir) channels in freshly isolated rat coronary arterial smooth muscle cells (RCASMCs). MAIN METHODS: The vascular tone of the endothelium-denuded RCAs was recorded by a wire myograph...
February 13, 2019: Life Sciences
Hongliang Li, Jin Ryeol An, Mi Seon Seo, Kwon-Soo Ha, Eun-Taek Han, Seok-Ho Hong, Won-Kyo Jung, Dae-Sung Lee, Mi-Jin Yim, Grace Choi, Jeong Min Lee, Young Min Bae, Il-Whan Choi, Won Sun Park
In the present study, we investigated the inhibitory effect of tacrolimus, a macrolide immunosuppressive drug that acts through calcineurin inhibition, on voltage-gated K+ (Kv) channels expressed in native smooth muscle cells isolated from the coronary arteries of rabbits. Tacrolimus reduced the amplitude of Kv currents in a dose-dependent manner with an IC50 value and Hill coefficient of 7.80 ± 3.01μM and 1.07 ± 0.25, respectively. Tacrolimus caused a shift in the activation curve toward a more positive potential and in the inactivation curve toward a more negative potential...
February 1, 2019: European Journal of Pharmacology
Michael A Masoomi, Iman Al-Shammeri, Khaled Kalafallah, Hany M A Elrahman, Osama Ragab, Ebba Ahmed, Jehan Al-Shammeri, Sharif Arafat
Many discrepancy in selection of proper filter and its parameters for individual cases exists. The authors investigate the impact of the most common filters on patient NM images with coronary artery disease (CAD), and compare the results with the computerized tomography (CT)-Angio and angiography for accuracy.The investigation initiated by performing various single photon emission computerized tomography (SPECT)/CT scan of the national electrical manufacturers association chest phantoms having hot and cold inserts...
January 2019: Medicine (Baltimore)
Michael K Pugsley, Sandro L Yong, Alan L Goldin, Eric S Hayes, Michael J A Walker
A series of amino-2-cyclohexyl ester derivatives were studied for their ion channel blocking and antiarrhythmic actions in the rat and a structure-activity analysis was conducted. The compounds are similar in chemical structure except for ionizable amine groups (pK values 6.1-8.9) and the positional arrangements of aromatic naphthyl moieties. Ventricular arrhythmias were produced in rats by coronary-artery occlusion or electrical stimulation. The electrophysiological effects of these compounds on rat heart sodium channels (Nav 1...
December 17, 2018: European Journal of Pharmacology
Rami M Abazid, Osama A Smettei, Ahmad Almeman, Sawsan Sayed, Hanaa Alsaqqa, Salma M Abdelmageed, Fahad J Alharbi, Abdullah M Alhabib, Mouaz H Al-Mallah
Introduction: Image noise can negatively affect the overall quality of coronary computed tomography angiography (CCTA). Objectives: The purpose of this study was to evaluate the relationship between image noise and fat volumes in the chest wall. We also aimed to compare these with other patient-specific predictors of image noise, such as body weight (BW) and body mass index (BMI). Methods: We undertook a cross-sectional, single-center study...
January 2019: Journal of the Saudi Heart Association
Davide Ippolito, Luca Riva, Cammillo R Talei Franzesi, Cecilia Cangiotti, Andrea De Vito, Filiberto Di Gennaro, Gabriele D'andrea, Andrea Crespi, Sandro Sironi
PURPOSE: To evaluate the image quality and radiation dose exposure of low-dose coronary CTA (cCTA) study, reconstructed with the new model-based iterative reconstruction algorithm (IMR), compared with standard hybrid-iterative reconstruction (iDose4 ) cCTA in patients with suspected coronary artery disease. MATERIALS AND METHODS: Ninety-eight patients with an indication for coronary CT study were prospectively enrolled. Fifty-two patients (study group) underwent 256-MDCT low-dose cCTA (80 kV; automated-mAs; 60 mL of CM, 350 mgL/mL) with prospective ECG-triggering acquisition and IMR...
December 11, 2018: La Radiologia Medica
Nienke G Eijsvoogel, Babs M F Hendriks, Jef L Willigers, Bibi Martens, Luc F Carati, Barbora Horehledova, Bastiaan L J H Kietselaer, Harry J G M Crijns, Joachim E Wildberger, Marco Das
PURPOSE: The aim was to assess personalised contrast media (CM) protocols-based on patient's blood volume (BV) and automated tube voltage selection (ATVS)-in coronary computed tomography angiography (CCTA). METHODS: A total of 114 consecutive patients received an ECG-triggered or ECG-gated helical scan on a 3rd-generation dual-source CT with 70-120kV (ATVS) and 330mAsqual.ref. CM was adapted to BV, scan time (s) and kV. Image quality (IQ) was assessed in a 17-segment coronary model using attenuation values (HU), contrast-to-noise (CNR), signal-to-noise ratio (SNR) (objective IQ) and a Likert scale (subjective IQ: 1 = poor/2 = sufficient/3 = good/4 = excellent)...
2018: PloS One
Jin Ryeol An, Hongliang Li, Mi Seon Seo, Won Sun Park
In this study, we demonstrated the inhibitory effect of the Class Ic antiarrhythmic agent propafenone on voltage-dependent K+ (Kv) channels using freshly isolated coronary artery smooth muscle cells from rabbits. The Kv current amplitude was progressively inhibited by propafenone in a dose-dependent manner, with an apparent IC50 value of 5.04±1.05 µM and a Hill coefficient of 0.78±0.06. The application of propafenone had no significant effect on the steady-state activation and inactivation curves, indicating that propafenone did not affect the voltage-sensitivity of Kv channels...
September 2018: Korean Journal of Physiology & Pharmacology
Rong Yang, Yu Liu, Xiaomin Hou, Yanying Fan, Jie Li, Min Chen, Yan Wang, Xuanping Zhang, Mingsheng Zhang
Acute coronary arterial spasm is contributory to ethanol-induced heart ischemic events. The present experiments were designed to study contractive effect of ethanol in isolated rat coronary arteries (RCAs) stimulated mildly with vasoconstrictors and involvement of voltage-gated potassium (KV ) channels and mitogen-activated protein kinases (MAPKs) of rat coronary arterial smooth muscle cell (RCASMC) in the spasm. The vascular tension was recorded with a wire myograph. KV currents of single freshly isolated RCASMC were assessed with patch clamp...
September 5, 2018: European Journal of Pharmacology
Jin Ryeol An, Hye Won Kim, Hongliang Li, Mi Seon Seo, Won-Kyo Jung, Kwon-Soo Ha, Eun-Taek Han, Seok-Ho Hong, Amy L Firth, Il-Whan Choi, Won Sun Park
This study examined the inhibitory effect of flecainide, a class 1c antiarrhythmic agent (Na+ channel blocker), on voltage-dependent K+ (Kv) channels in smooth muscle cells isolated from coronary arteries. Flecainide decreased the vascular Kv channel current in a dose-dependent manner with an IC50 value of 5.90 ± 0.87 μmol/L and a Hill coefficient of 0.77 ± 0.06. Although the steady-state activation curve was not affected by flecainide, it shifted the steady-state inactivation curves toward a more negative potential...
December 2018: Clinical and Experimental Pharmacology & Physiology
Robert Novotný, Dáša Slížová, Jaroslav Hlubocký, Otakar Krs, Jaroslav Špatenka, Jan Burkert, Radovan Fiala, Petr Mitáš, Pavel Mĕricka, Miroslav Špaček, Zuzana Hlubocká, Jaroslav Lindner
BACKGROUND: The aim of our experimental work was to assess the impact and morphological changes that arise during different thawing protocols on human aortic valve (AV) leaflets resected from cryopreserved aortic root allografts (CARAs). OBJECTIVES: Two thawing protocols were tested: 1. CARAs were thawed at a room temperature (23°C); 2. CARAs were placed directly into a water bath at a temperature of 37°C. After all the samples were thawed, non-coronary AV leaflets were sampled from each specimen and fixed in a 4% formaldehyde solution before they were sent for morphological analysis...
August 2018: Advances in Clinical and Experimental Medicine: Official Organ Wroclaw Medical University
Tilman Hickethier, Bettina Baeßler, Jan Robert Kroeger, Dirk Müller, David Maintz, Guido Michels, Alexander C Bunck
Background Advanced knowledge-based iterative model reconstructions (IMR) became recently available for routine computed tomography (CT). Using more realistic physical models it promises improved image quality and potential radiation dose reductions, both possibly beneficial for non-invasive assessment of coronary stents. Purpose To evaluate the influence of different IMR settings at different radiation doses on stent lumen visualization in comparison to filtered back projection (FBP) and first-generation (hybrid) iterative reconstruction (HIR)...
January 1, 2018: Acta Radiologica
Hongliang Li, Sung Eun Shin, Jin Ryeol An, Mi Seon Seo, Kwon-Soo Ha, Eun-Taek Han, Seok-Ho Hong, Amy L Firth, Dae-Sung Lee, Mi-Jin Yim, Jeong Min Lee, Grace Choi, Il-Whan Choi, Won Sun Park
We investigated the effect of the tricyclic antidepressant clomipramine on voltage-dependent K+ (Kv) channels in native rabbit coronary arterial smooth muscle cells. Our results showed that clomipramine inhibited vascular Kv channels in a concentration-dependent manner, with an IC50 value of 8.61 ± 4.86 μM and a Hill coefficient (n) of 0.58 ± 0.07. The application of 10 μM clomipramine did not affect the activation curves of the Kv channels; however, the inactivation curves of the Kv channels were shifted toward a more negative potential...
May 2018: Journal of Pharmacological Sciences
Nienke G Eijsvoogel, Babs M F Hendriks, Hugo B Park, Sibel Altintas, Casper Mihl, Barbora Horehledova, Bastiaan L J H Kietselaer, Harry J G M Crijns, Joachim E Wildberger, Marco Das
Modern high-performance computed tomography (CT) scanners with improved scan acquisition times now allow for routine assessment of cardiac pathologies on chest CTs, which can result in numerous incidental cardiac findings. The CaPaCT study, an observer blinded, single-centre study, aims to assess the visibility, management and possible clinical impact of incidental cardiac pathologies that are now becoming visible on standard chest CTs. A total of 217 consecutive patients referred for a chest CT on a high-performance third-generation dual-source CT scanner will be included...
2018: European Radiology Experimental
Chunhong Wang, Yuliang Liao, Haibin Chen, Xin Zhen, Jianhong Li, Yikai Xu, Linghong Zhou
Previous studies have shown that employing the low dose computed tomography (CT) technique based on low tube potential reduces the radiation dose required for the coronary artery examination protocol. However, low tube potential may adversely influence the CT number of plaque composition. Therefore, we aimed to determine whether quantitative atherosclerotic plaque analysis by a multi-slice, low radiation dose CT protocol using 80 kilovolts (kV) yields results comparable to those of the standard 120 kV protocol...
August 2018: International Journal of Cardiovascular Imaging
Moritz H Albrecht, Matthew W Bickford, U Joseph Schoepf, Christian Tesche, Domenico De Santis, Marwen Eid, Brian E Jacobs, Taylor M Duguay, Bernhard T Schmidt, Christian Canstein, Akos Varga-Szemes, Doris Leithner, Simon Martin, Thomas J Vogl, Carlo N De Cecco
PURPOSE: To investigate the effect of an iterative beam-hardening correction algorithm (iBHC) on artifact reduction and image quality in coronary CT angiography (cCTA) with low tube voltage. MATERIAL AND METHODS: Thirty-six patients (17 male, mean age, 57.3 ± 14.5 years) were prospectively enrolled in this IRB-approved study and underwent 70-kV cCTA using a third-generation dual-source CT scanner. Images were reconstructed using a standard algorithm (Bv36) both with and without the iBHC technique...
April 2018: European Journal of Radiology
Shihe Liu, Qing Fu, Hualong Yu, Chuanyu Zhang, Qing Yang, Yabin Hu, Wenjian Xu
BACKGROUND: 640-slice coronary CT angiography is becoming an accurate and reliable method of diagnosing coronary heart disease. However, how to reduce the radiation dosage while ensuring the clinically acceptable image quality remains a quite challenging issue. OBJECTIVE: To evaluate the effect of low tube voltage on radiation dosage under 640-slice coronary CT angiography (CCTA). METHODS: Four hundred patients (236 males, 164 females) with coronary heart disease and underwent CCTA using DCVT were classified into A1 (tube voltage: 120 kV; exposure phase window: 30-80%), B1 (120 kV; 70-80%), A2 (100 kV; 30-80%) and B2 group (100 kV; 70-80%), respectively...
2018: Journal of X-ray Science and Technology
Hong Seon Lee, Young Joo Suh, Kyunghwa Han, Jin Young Kim, Suyon Chang, Dong Jin Im, Yoo Jin Hong, Hye-Jeong Lee, Jin Hur, Young Jin Kim, Byoung Wook Choi
BACKGROUND: Reduced image quality from increased X-ray scatter and image noise can be problematic when coronary computed tomography angiography (CCTA) imaging is performed in obese patients. The aim of this study was to compare the image quality and radiation dose obtained using automatic tube potential selection with tube current modulation (APSCM) with those obtained using a body mass index (BMI)-based protocol for CCTA in obese patients. METHODS: A total of 203 consecutive obese (BMI > 30 kg/m2) patients were retrospectively enrolled, of whom 96 underwent CCTA with APSCM and 107 underwent a BMI-based protocol...
2018: PloS One
Yoshinori Nishijima, Ankush Korishettar, Dawid S Chabowski, Sheng Cao, Xiaodong Zheng, David D Gutterman, David X Zhang
OBJECTIVES: KV channels are important regulators of vascular tone, but the identity of specific KV channels involved and their regulation in disease remain less well understood. We determined the expression of KV 1 channel subunits and their role in cAMP-mediated dilation in coronary resistance arteries from subjects with and without CAD. METHODS: HCAs from patients with and without CAD were assessed for mRNA and protein expression of KV 1 channel subunits with molecular techniques and for vasodilator response with isolated arterial myography...
January 2018: Microcirculation: the Official Journal of the Microcirculatory Society, Inc
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"