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https://www.readbyqxmd.com/read/28229626/the-role-of-hydrogen-sulfide-in-homocysteine-induced-cardiodynamic-effects-and-oxidative-stress-markers-in-the-isolated-rat-heart
#1
M Stojanovic, V Zivkovic, I Srejovic, V Jakovljevic, N Jeremic, D Djuric
This study aimed to assess the role of H2S in homocysteine-induced cardiodynamic effects in the isolated rat heart. The hearts were retrogradely perfused according to the Langendorff technique. The maximum and minimum rates of pressure in the left ventricle (dp/dt max, dp/dt min), systolic and diastolic left ventricular pressures (SLVP, DLVP), heart rate (HR), and coronary flow (CF) were measured. A spectrophotometrical method was used to measure the following oxidative stress markers: index of lipid peroxidation (thiobarbituric acid reactive substances, TBARS), nitrite level (NO2(-)), superoxide anion radicals (O2(•-)), and hydrogen peroxide (H2O2) concentrations...
December 2016: Physiol Int
https://www.readbyqxmd.com/read/28228405/inhibition-of-romk-blocks-macula-densa-tubuloglomerular-feedback-yet-causes-renal-vasoconstriction-in-anesthetized-rats
#2
Magali Araujo, William J Welch, Xiaoyan Zhou, Kathleen Sullivan, Shawn Walsh, Alexander Pasternak, Christopher S Wilcox
The Na+/K+/2Cl- cotransporter (NKCC2) on the loop of Henle is the site of action of furosemide. Since outer medullary potassium channel (ROMK) inhibitors prevent reabsorption by NKCC2, we tested the hypothesis that ROMK inhibition with a novel, selective ROMK inhibitor (Compound C) blocks tubuloglomerular feedback (TGF) and reduces vascular resistance. Loop perfusion of either ROMK inhibitor or furosemide caused dose-dependent blunting of TGF, but the response to furosemide was 10-fold more sensitive (IC50= 10-6M for furosemide and IC50=10-5M for Compound C)...
February 22, 2017: American Journal of Physiology. Renal Physiology
https://www.readbyqxmd.com/read/28227463/hemodynamic-effects-of-synchronizing-an-intra-aortic-vad-in-reverse-rotation-control-with-left-ventricle-a-mock-loop-study
#3
Yaxin Wang, P Alex Smith, Daniel L Timms, Po-Lin Hsu, Richard A McMahon, Yaxin Wang, P Alex Smith, Daniel L Timms, Po-Lin Hsu, Richard A McMahon, Richard A McMahon, Daniel L Timms, Po-Lin Hsu, Yaxin Wang, P Alex Smith
The IntraVAD is an intra-aortic left ventricular assist device (LVAD) to be located in the ascending aorta. In order to enhance unloading and promote coronary flow for the left ventricle (LV), an operating mechanism, reverse-rotation control (RRc) mode, has been developed for the IntraVAD and tested in vitro in a mock circulation loop (MCL). The RRc mode consists of forward rotation (FR) and reverse rotation (RR). The synchronization between the IntraVAD and the LV was studied to offload the ventricle more effectively and to improve myocardial perfusion...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227085/an-object-oriented-model-of-the-cardiopulmonary-system-with-emphasis-on-the-gravity-effect
#4
Chuong Ngo, Silvia Briones Herranz, Berno Misgeld, Thomas Vollmer, Steffen Leonhardt, Chuong Ngo, Silvia Briones Herranz, Berno Misgeld, Thomas Vollmer, Steffen Leonhardt, Thomas Vollmer, Steffen Leonhardt, Chuong Ngo, Berno Misgeld
We introduce a novel comprehensive model of the cardiopulmonary system with emphasis on perfusion and ventilation distribution along the vertical thorax axis under the gravity effect. By using an object-oriented environment, the complex physiological system can be represented by a network of electrical, lumped-element compartments. The lungs are divided into three zones: upper, middle, and lower zone. Blood flow increases with the distance from the apex to the base of the lungs. The upper zone is characterized by a complete collapse of the pulmonary capillary vasculature; thus, there is no flow in this zone...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226987/blood-viscosity-monitoring-during-cardiopulmonary-bypass-based-on-pressure-flow-characteristics-of-a-newtonian-fluid
#5
Shigeyuki Okahara, Zu Soh, Shinya Takahashi, Taijiro Sueda, Toshio Tsuji, Shigeyuki Okahara, Zu Soh, Shinya Takahashi, Taijiro Sueda, Toshio Tsuji, Zu Soh, Toshio Tsuji, Shinya Takahashi, Taijiro Sueda, Shigeyuki Okahara
We proposed a blood viscosity estimation method based on pressure-flow characteristics of oxygenators used during cardiopulmonary bypass (CPB) in a previous study that showed the estimated viscosity to correlate well with the measured viscosity. However, the determination of the parameters included in the method required the use of blood, thereby leading to high cost of calibration. Therefore, in this study we propose a new method to monitor blood viscosity, which approximates the pressure-flow characteristics of blood considered as a non-Newtonian fluid with characteristics of a Newtonian fluid by using the parameters derived from glycerin solution to enable ease of acquisition...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28222055/ex-situ-perfusion-of-human-limb-allografts-for-24-hours
#6
Nicole L Werner, Fares Alghanem, Stephanie L Rakestraw, Dylan C Sarver, Bruce Nicely, Richard E Pietroski, Paul Lange, Steven M Rudich, Christopher L Mendias, Alvaro Rojas-Pena, John C Magee, Robert H Bartlett, Kagan Ozer
BACKGROUND: Vascularized composite allografts, particularly hand and forearm, have limited ischemic tolerance after procurement. In bilateral hand transplantations, this demands a 2 team approach and expedited transfer of the allograft, limiting the recovery to a small geographic area. Ex situ perfusion may be an alternative allograft preservation method to extend allograft survival time. This is a short report of 5 human limbs maintained for 24 hours with ex situ perfusion. METHODS: Upper limbs were procured from brain-dead organ donors...
March 2017: Transplantation
https://www.readbyqxmd.com/read/28219356/bacopa-monnieri-extract-increases-rat-coronary-flow-and-protects-against-myocardial-ischemia-reperfusion-injury
#7
Sirintorn Srimachai, Sylvie Devaux, Celine Demougeot, Sarawut Kumphune, Nina D Ullrich, Ernst Niggli, Kornkanok Ingkaninan, Natakorn Kamkaew, C Norman Scholfield, Sompol Tapechum, Krongkarn Chootip
BACKGROUND: This study explored Bacopa monnieri, a medicinal Ayurvedic herb, as a cardioprotectant against ischemia/reperfusion injury using cardiac function and coronary flow as end-points. METHODS: In normal isolated rat hearts, coronary flow, left ventricular developed pressure, heart rate, and functional recovery were measured using the Langendorff preparation. Hearts were perfused with either (i) Krebs-Henseleit (normal) solution, (control), or with 30, 100 μg/ml B...
February 20, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28217316/subacute-right-heart-failure-revealing-three-simultaneous-causes-of-post-embolic-pulmonary-hypertension-in-metastatic-dissemination-of-breast-cancer
#8
Flavien Vincent, Nicolas Lamblin, Marion Classe, Guillaume Schurtz, Antoine Rauch, Marie Fertin, Pascal De Groote
A 72-year-old woman with history of breast cancer only treated surgically was referred to our department for pulmonary hypertension (PH) suspicion. Echocardiogram revealed elevated right ventricular systolic pressure. Computed tomography (CT) angiogram showed no pulmonary embolism (PE), but lung scan revealed two ventilation-perfusion mismatch areas. Right cardiac catheterization established precapillary PH. Despite treatment with PH specific therapy (sildenafil, ambrisentan, and epoprostenol), her condition worsened rapidly with acute right heart failure (RHF)...
February 2017: ESC Heart Failure
https://www.readbyqxmd.com/read/28216699/comparison-of-volume-controlled-ventilation-and-pressure-controlled-ventilation-in-patients-undergoing-robot-assisted-pelvic-surgeries-an-open-label-trial
#9
Rishabh Jaju, Pooja Bihani Jaju, Mamta Dubey, Sadik Mohammad, A K Bhargava
BACKGROUND AND AIMS: Although volume controlled ventilation (VCV) has been the traditional mode of ventilation in robotic surgery, recently pressure controlled ventilation (PCV) has been used more frequently. However, evidence on whether PCV is superior to VCV is still lacking. We intended to compare the effects of VCV and PCV on respiratory mechanics and haemodynamic in patients undergoing robotic surgeries in steep Trendelenburg position. METHODS: This prospective, randomized trial was conducted on sixty patients between 20 and 70 years belonging to the American Society of Anesthesiologist Physical Status I-II...
January 2017: Indian Journal of Anaesthesia
https://www.readbyqxmd.com/read/28216049/chronic-treatment-with-fluoxetine-modulates-vascular-adrenergic-responses-by-inhibition-of-pre-and-post-synaptic-mechanisms
#10
Camila A Pereira, Fernanda L Rodrigues, Silvia G Ruginsk, Camila Z Zanotto, José A Rodrigues, Diego A Duarte, Claudio M Costa-Neto, Leonardo B Resstel, Fernando S Carneiro, Rita C Tostes
Fluoxetine, a serotonin reuptake inhibitor (SSRI), has other effects in addition to blocking serotonin reuptake, including changes in the vasomotor tone. Whereas many studies focused on the acute effects of fluoxetine in the vasculature, its chronic effects are still limited. In the present study, we tested the hypothesis that chronic fluoxetine treatment modulates adrenergic vascular responses by interfering with post- and pre-synaptic mechanisms. Wistar rats were treated with vehicle (water) or chronic fluoxetine (10mg/kg/day) for 21 days...
February 16, 2017: European Journal of Pharmacology
https://www.readbyqxmd.com/read/28215591/the-effect-of-resuscitation-position-on-cerebral-and-coronary-perfusion-pressure-during-mechanical-cardiopulmonary-resuscitation-in-porcine-cardiac-arrest-model
#11
Taeyun Kim, Sang Do Shin, Kyoung Jun Song, Yong Joo Park, Hyun Ho Ryu, Guillaume Debaty, Keith Lurie, Ki Jeong Hong
OBJECTIVE: Automated cardiopulmonary resuscitation (CPR) devices can be used during transport in a small spaces (e.g. an elevator) to reduce the length of stretcher and via body position change. It is unknown whether patient position is associated with the optimal cerebral (CePP) and coronary (CoPP) perfusion pressure. METHODS: This study utilized a randomized experimental design and anesthetized, intubated and paralyzed female pigs (n=12) (mean 42, SD 3kg) on a customized tilt table...
February 16, 2017: Resuscitation
https://www.readbyqxmd.com/read/28215427/method-of-hypertonic-saline-administration-effects-on-osmolality-in-traumatic-brain-injury-patients
#12
Kelly L Maguigan, Bradley M Dennis, Susan E Hamblin, Oscar D Guillamondegui
Hypertonic saline (HTS) is an effective therapy for reducing intracranial pressure (ICP). The ideal method of administration is unknown. The purpose of this study was to evaluate the method of HTS infusion and time to goal osmolality. A retrospective cohort analysis was conducted in severe TBI patients with ICP monitoring in place who received 2 doses of HTS. Patients were divided into bolus versus continuous infusion HTS cohorts. The primary outcome was median time to goal osmolality. Secondary outcomes included percentage of patients reaching goal osmolality, percent time at goal osmolality, mean cerebral perfusion pressure (CPP) and ICP, ICU length of stay, and mortality...
February 15, 2017: Journal of Clinical Neuroscience: Official Journal of the Neurosurgical Society of Australasia
https://www.readbyqxmd.com/read/28213770/myosin-heavy-chain-and-cardiac-troponin-t-damage-is-associated-with-impaired-myofibrillar-atpase-activity-contributing-to-sarcomeric-dysfunction-in-ca-2-paradox-rat-hearts
#13
Árpád Kovács, Judit Kalász, Enikő T Pásztor, Attila Tóth, Zoltán Papp, Naranjan S Dhalla, Judit Barta
This study aimed to explore the potential contribution of myofibrils to contractile dysfunction in Ca(2+)-paradox hearts. Isolated rat hearts were perfused with Krebs-Henseleit solution (Control), followed by Ca(2+)-depletion, and then Ca(2+)-repletion after Ca(2+)-depletion (Ca(2+)-paradox) by Langendorff method. During heart perfusion left ventricular developed pressure (LVDP), end-diastolic pressure (LVEDP), rate of pressure development (+ dP/dt), and pressure decay (-dP/dt) were registered. Control LVDP (127...
February 17, 2017: Molecular and Cellular Biochemistry
https://www.readbyqxmd.com/read/28207907/argon-does-not-affect-cerebral-circulation-or-metabolism-in-male-humans
#14
Frank Grüne, Stephan Kazmaier, Sanne Elisabeth Hoeks, Robert Jan Stolker, Marc Coburn, Andreas Weyland
OBJECTIVE: Accumulating data have recently underlined argon´s neuroprotective potential. However, to the best of our knowledge, no data are available on the cerebrovascular effects of argon (Ar) in humans. We hypothesized that argon inhalation does not affect mean blood flow velocity of the middle cerebral artery (Vmca), cerebral flow index (FI), zero flow pressure (ZFP), effective cerebral perfusion pressure (CPPe), resistance area product (RAP) and the arterio-jugular venous content differences of oxygen (AJVDO2), glucose (AJVDG), and lactate (AJVDL) in anesthetized patients...
2017: PloS One
https://www.readbyqxmd.com/read/28207868/acetylcholine-versus-cold-pressor-testing-for-evaluation-of-coronary-endothelial-function
#15
Ahmed AlBadri, Janet Wei, Puja K Mehta, Sofy Landes, John W Petersen, R David Anderson, Bruce Samuels, Babak Azarbal, Eileen M Handberg, Quanlin Li, Margo Minissian, Chrisandra Shufelt, Carl J Pepine, C Noel Bairey Merz
BACKGROUND: Assessment of coronary endothelial function with intracoronary acetylcholine (IC-Ach) provides diagnostic and prognostic data in patients with suspected coronary microvascular dysfunction (CMD), but is often not feasible due in part to the time and expertise needed for pharmacologic mixing. Cold pressor testing (CPT) is a simple and safe stimulus useful for either invasive or non-invasive endothelial function testing and myocardial perfusion imaging but has not been specifically evaluated among symptomatic women with signs of ischemic heart disease (IHD) who have no obstructive coronary artery disease (CAD)...
2017: PloS One
https://www.readbyqxmd.com/read/28203185/reversible-cerebral-vasoconstriction-syndrome-with-intracranial-hypertension-should-decompressive-craniectomy-be-considered
#16
Ségolène Mrozek, Laurent Lonjaret, Aude Jaffre, Anne-Christine Januel, Nicolas Raposo, Sergio Boetto, Jean-François Albucher, Olivier Fourcade, Thomas Geeraerts
BACKGROUND: Reversible cerebral vasoconstriction syndrome (RCVS) is a rare cause of intracerebral hemorrhage (ICH) causing intracranial hypertension. METHODS: Case report. RESULTS: We report a case of RCVS-related ICH leading to refractory intracranial hypertension. A decompressive craniectomy was performed to control intracranial pressure. We discuss here the management of RCVS with intracranial hypertension. Decompressive craniectomy was preformed to avoid the risky option of high cerebral perfusion pressure management with the risk of bleeding, hemorrhagic complications, and high doses of norepinephrine...
January 2017: Case Reports in Neurology
https://www.readbyqxmd.com/read/28202440/exposure-to-placental-ischemia-impairs-postpartum-maternal-renal-and-cardiac-function-in-rats
#17
Nina D Paauw, Jaap A Joles, Frank T Spradley, Bhavisha Bakrania, Zsuzsanna K Zellenger, Arie Franx, Marianne C Verhaar, Joey P Granger, A Titia Lely
INTRODUCTION: Women with a history of preeclampsia (PE) have an increased risk to develop cardiovascular and renal diseases later in life, but the mechanisms underlying this effect are unknown. In rats, we assessed whether placental ischemia results in long-term effects on the maternal cardiovascular and renal systems using the Reduced Uterine Perfusion Pressure (RUPP) model for PE. METHODS: Sprague-Dawley rats received either a SHAM or RUPP operation at gestational day 14...
February 15, 2017: American Journal of Physiology. Regulatory, Integrative and Comparative Physiology
https://www.readbyqxmd.com/read/28202246/analysis-of-myocardial-perfusion-parameters-in-an-ex-vivo-porcine-heart-model-using-third-generation-dual-source-ct
#18
Gert Jan Pelgrim, Taylor M Duguay, J Marco A Stijnen, Akos Varga-Szemes, Sjoerd Van Tuijl, U Joseph Schoepf, Matthijs Oudkerk, Rozemarijn Vliegenthart
PURPOSE: To evaluate the relationship between fractional flow reserve (FFR)-determined coronary artery stenosis severity and myocardial perfusion parameters derived from dynamic myocardial CT perfusion imaging (CTP) in an ex-vivo porcine heart model. METHODS: Six porcine hearts were perfused according to Langendorff. Circulatory parameters such as arterial blood flow (ABF) (L/min), mean arterial pressure (MAP) (mmHg) and heart rate (bpm) were monitored. Using an inflatable cuff and monitored via a pressure wire, coronary artery stenoses of different FFR grades were created (no stenosis, FFR = 0...
February 3, 2017: Journal of Cardiovascular Computed Tomography
https://www.readbyqxmd.com/read/28202085/should-capnography-be-used-as-a-guide-for-choosing-a-ventilation-strategy-in-circulatory-shock-caused-by-severe-hypothermia-observational-case-series-study
#19
Tomasz Darocha, Sylweriusz Kosiński, Anna Jarosz, Paweł Podsiadło, Mirosław Ziętkiewicz, Tomasz Sanak, Robert Gałązkowski, Jacek Piątek, Janusz Konstanty-Kalandyk, Rafał Drwiła
BACKGROUND: Severe accidental hypothermia can cause circulatory disturbances ranging from cardiac arrhythmias through circulatory shock to cardiac arrest. Severity of shock, pulmonary hypoperfusion and ventilation-perfusion mismatch are reflected by a discrepancy between measurements of CO2 levels in end-tidal air (EtCO2) and partial CO2 pressure in arterial blood (PaCO2). This disparity can pose a problem in the choice of an optimal ventilation strategy for accidental hypothermia victims, particularly in the prehospital period...
February 15, 2017: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine
https://www.readbyqxmd.com/read/28198536/prevalence-of-risk-factors-and-asymptomatic-carotid-atherosclerosis-in-diabetic-patients-screened-for-silent-myocardial-ischemia-by-spect-myocardial-imaging
#20
Irena Peovska Mitevska, Natalija Baneva, Marijan Bosevski, Elizabeta Srbinovska Kostovska
BACKGROUND: The aim of the study was to evaluate whether there is any association between myocardial ischemia, common risk factors and carotid artery ultrasound parameters in asymptomatic type 2 diabetic (DMT2) patients. MATERIAL AND METHODS: 60 asymptomatic DMT2 patients (pts) without known coronary artery disease (CAD) underwent one day rest Dypiridamole stress Tc-99m sestamibi single photon emission computed tomography myocardial perfusion scintigraphy (MPS)...
2017: Nuclear Medicine Review. Central & Eastern Europe
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