tbuckley/cabot-search huggingface dataset:
Body surface detection of delayed depolarizations in patients with recurrent ventricular tachycardia and left ventricular aneurysm.
Authors: J JRozanski, DMortara, R JMyerburg, ACastellanos
Journal: Circulation (1981)

In eight patients with chronic ventricular tachycardia and left ventricular aneurysms, we detected delayed ECG wave forms after the QRS complex from the body surface using a high-resolution ECG recorder, amplification and signal averaging. Delayed wave-form activity (D wave) extended a mean of 70 msec beyond the termination of th QRS complex. This delayed activity frequently extended to the limit of the recording window, and may thus continue throughout much of diastole. Antiarrhythmic agents never abolished the delayed activity; however, it was abolished by aneurysmectomy in four patients. Ventricular tachycardia did not recur after surgery in the four patients during a mean follow-up of 1 year. The D wave was not found in eight control patients who had chronic recurrent ventricular tachycardia nor in 11 of 12 who had aneurysms alone. The surface D wave can be readily and reproducibly detected by high-resolution electrocardiography and appears to be specific for patients with left ventricular aneurysms w...
Improved regional myocardial blood flow, left ventricular unloading, and infarct salvage using an axial-flow, transvalvular left ventricular assist device. A comparison with intra-aortic balloon counterpulsation and reperfusion alone in a canine infarction model.
Authors: R WSmalling, D BCassidy, RBarrett, BLachterman, PFelli, JAmirian
Journal: Circulation (1992)

BACKGROUNDIt has been suggested that left ventricular unloading at the time of reperfusion provides superior infarct salvage over reperfusion alone. The purpose of this study was to show that the Hemopump transvalvular axial-flow left ventricular assist device provides superior left ventricular unloading, ischemic zone collateral blood flow, and infarct size reduction compared with intra-aortic balloon counterpulsation and reperfusion alone.METHODS AND RESULTSEighteen dogs were instrumented with regional myocardial function sonomicrometers in the ischemic and control zones. The left anterior descending coronary artery just distal to the first diagonal branch was instrumented with a silk snare and Doppler flow probe. Additionally, pressure catheters were placed in the left atrial appendage, left ventricular apex, and ascending aorta for hemodynamic measurements. Regional myocardial blood flow was determined by using 15-microns radioactive microspheres. Measurements were made in the control state, immediate...
The role of angiotensins in aldosterone production.
Authors: E LBravo, M CKhosla, F MBumpus
Journal: Circulation Research (1976)

The hypothesis that the COOH-terminal heptapeptide mediates the aldosterone-stimulating activity of angiotensin II was evaluated by comparing the relative effects on aldosterone production of angiotensin II and the heptapeptide to angiotensin analogues that are poorly metabolized to the heptapeptide and to a nonapeptide, des-Asp-1-angiotensin I, that is directly converted to the heptapeptide. In in vivo studies utilizing the adrenocorticotropic hormone-suppressed bilaterally nephrectomized dog, angiotensin II and the heptapeptide produced statistically significant increases in both aldosterone and cortisol secretory rates (P less than 0.001 for both relations). Sar-1-angiotensin II stimulated the production of both steroids to the same extent, but had much longer duration of action. [Poly(oAc)Seryl]angiotensin II was a weak agonist, having only about 30% of the steroidogenic potency of either angiotensin II or the heptapeptide. In equimolar concentrations des-Asp-1-angiotensin I had about one-half of the ...
Myocardial protection during transient coronary artery occlusion in man: beneficial effects of regional beta-adrenergic blockade.
Authors: AZalewski, SGoldberg, J PDervan, SSlysh, P RMaroko
Journal: Circulation (1986)

The goal of this study was to verify whether myocardial protection could be achieved via the intracoronary administration of propranolol in patients undergoing percutaneous transluminal coronary angioplasty (PTCA). Accordingly, 21 patients undergoing PTCA were randomly assigned to receive either intracoronary placebo (group A, n = 10) or intracoronary propranolol (group B, n = 11). Three balloon inflations (i.e., coronary artery occlusions) were performed in each patient. Inflations I and II (maximum duration 60 sec) served as control occlusions. Inflation III (maximum duration 120 sec) was performed either after intracoronary administration of saline (2 ml) or propranolol (1.1 +/- 0.2 mg). The following electrocardiographic index of myocardial ischemic injury were measured: (1) time to development of ST segment elevation equal to 0.1 mV and (2) magnitude of ST segment elevation after 60 sec of coronary artery occlusion. Both indexes did not differ significantly between the groups during inflations I and ...
Delineation of myocardial oxygen utilization with carbon-11-labeled acetate.
Authors: MBrown, D RMarshall, B ESobel, S RBergmann
Journal: Circulation (1987)

Although positron-emission tomography (PET) with labeled fatty acid delineates infarct size and permits qualitative assessment of fatty acid utilization, quantification of oxidative metabolism is limited by complex alterations in the pattern of utilization of fatty acid during ischemia and reperfusion. Because metabolism of acetate by myocardium is less complex than that of glucose or palmitate, we characterized kinetics of utilization of radiolabeled acetate in 37 isolated rabbit hearts perfused with modified Krebs-Henseleit buffer and performed a pilot tomographic study in man. Results of initial experiments with carbon-14-labeled acetate (14C-acetate) indicated that the steady-state extraction fraction of acetate averaged 61.5 +/- 4.0% in control hearts (n = 4), 93.6 +/- 0.9% in hearts rendered ischemic (n = 4), and 54.8 +/- 4.0% in hearts reperfused after 60 min of ischemia (n = 3). Oxidation of 14C-acetate, assessed from the rate of efflux of 14CO2 in the venous effluent, correlated closely with the ...
Effect of adenosine on atrioventricular conduction. I: Site and characterization of adenosine action in the guinea pig atrioventricular node.
Authors: H FClemo, LBelardinelli
Journal: Circulation Research (1986)

Adenosine has a negative dromotropic effect and modulates hypoxia-induced atrioventricular (AV) conduction delay. To further characterize the negative dromotropic effect of adenosine in the guinea pig heart, we determined the site of adenosine-induced AV conduction block; the effect of uptake and deamination of adenosine on its concentration-negative dromotropic effect, and the adenosine receptor that mediates this action. In isolated AV node preparations (n = 16), adenosine in a dose-dependent manner decreased significantly the duration and amplitude of the action potential of atrionodal and nodal cells and, in addition, markedly depressed the maximum rate of rise of the action potential of nodal cells. At high concentrations (greater than 20 microM), adenosine rendered nodal cells inexcitable. In isolated perfused hearts (n = 7), adenosine (5.7 microM) prolonged total AV conduction time by 21 +/- 2 msec. Of this prolongation, 83% was due to an increase in the nodal-to-His-bundle interval and the remaini...
Progressive hypoxemia limits left ventricular oxygen consumption and contractility.
Authors: K RWalley, C JBecker, R AHogan, KTeplinsky, L DWood
Journal: Circulation Research (1988)

To study the cardiac effects of progressive hypoxemia, we measured the left ventricular end-systolic pressure-volume relation (ESPVR), myocardial oxygen consumption (MVO2), and myocardial oxygen delivery (MQO2) in eight thoracotomized dogs anesthetized with fentanyl and droperidol. We specifically looked for evidence of oxygen supply limitation of MVO2 and depressed contractility (altered ESPVR) during stepwise decreases in inspired oxygen fraction. We hypothesized that the reported relation between MVO2 and left ventricular pressure-volume area (PVA) may hold when inadequate MQO2 determines MVO2, which then may limit PVA, manifested partly as a change in the ESPVR. Initially, as arterial oxygen saturation was decreased from 95 +/- 3% to 64 +/- 14%, coronary blood flow increased so that MQO2 was maintained with no change in myocardial extraction ratio (ERm = MVO2/MQO2). During this first phase, lactate utilization, PVA, and ESPVR did not change. When oxygen saturation was further reduced, coronary blood f...
Abstract PD5-11: Not presented
Authors: A Bardia, DA Yardley, S Hurvitz, G Wright, R Moroose, C Ma, L Hart, E Tan-Chiu, S Blau, T Sanft, R Dichmann, A Zelnak, A DeMichele, A Clark, T Small, C Tucci, TS Samant, D Purkayastha, M Karuturi, S Moulder
Journal: Cancer Research (2018)

Abstract This abstract was not presented at the symposium.
Overlap of Rome IV Irritable Bowel Syndrome and Functional Dyspepsia and Effect on Natural History: A Longitudinal Follow-Up Study
Authors: Brigida Barberio, Yan Yiannakou, Lesley A. Houghton, Christopher J. Black, Edoardo V. Savarino, Alexander C. Ford
Journal: Clinical Gastroenterology and Hepatology (2021)
Role of LDL receptors in the in vitro uptake and degradation of LDL in the media of rabbit thoracic aorta.
Authors: P ACurmi, GRenaud, LJuan, BChiron, ATedgui
Journal: Circulation Research (1989)

The possible role of plasma low-density protein (LDL) receptors in the uptake and degradation of LDL in the whole arterial wall was investigated by comparison of the in vitro uptake of 125I-native LDL (nLDL) and 131I-methylated LDL (mLDL) by the media of deendothelialized rabbit thoracic aorta excised at in vivo length and pressurized to 70 mm Hg, taking the advantage that mLDL is not recognized by the LDL receptor. The distribution of the relative concentrations of nLDL (Cn) and mLDL (Cm) across the wall was obtained using a serial frozen sectioning technique. The aorta was incubated under three different conditions for varying periods of incubation in order to analyze separately the processes of binding, binding-internalization, and degradation. At 39 degrees C, in which binding-internalization and degradation occurred, Cn was significantly higher than Cm at each position across the media. The mean medial Cn/Cm ratio was 1.36 +/- 0.15 (n = 5) after 1 hour of incubation, and decreased to 1.23 +/- 0.22 (n...
Hemodynamic consequences of afterload reduction in patients with chronic aortic regurgitation.
Authors: J LBolen, E LAlderman
Journal: Circulation (1976)

Nitroprusside was used to reduce afterload in 13 patients with isolated, severe aortic regurgitation. The drug significantly lowered mean aortic pressure, pulse pressure, left ventricular end-diastolic pressure and left ventricular volume. Total ventricular, or angiographic, cardiac index was generally unaffected, but forward cardiac index was improved significantly in 8 of 13 patients. Augmentation of forward cardiac index was seen in patients with subnormal resting forward cardiac index, in patients with decidedly elevated end-diastolic pressure, and in those with depressed resting ejection fractions. Regurgitant fraction fell with nitroprusside in six patients and remained unchanged in seven. Total stroke work index was diminished in all patients. These data show that afterload reduction in patients with severe aortic regurgitation may improve hemodynamics by reducing aortic regurgitation or by improving ventricular pump function. The lowered total stroke work, reduced ventricular size and improved for...
Early outward current in rat single ventricular cells.
Authors: I RJosephson, JSanchez-Chapula, A MBrown
Journal: Circulation Research (1984)

Voltage clamp experiments were conducted using single ventricular myocytes which had been dissociated enzymatically from adult rat hearts in order to examine further the membrane currents which contribute to the unusual plateau of the rat action potential. Membrane currents were recorded, using a single microelectrode (switching) voltage clamp circuit. From holding potentials near the resting potential (-80 to -90 mV), depolarizing clamp steps above -20 mV elicited an early outward current which overlapped in time with the slow inward current and displayed time-dependent inactivation. This is the first demonstration of a transient potassium current in an isolated ventricular myocyte. The early outward potential was voltage-inactivated at holding potentials of -50 to -40 mV and was blocked by 4-aminopyridine. The current was not dependent on Cao or ICa and was blocked by Bao. Double pulse experiments revealed that the time course for the recovery of the early outward current at -80 mV was rapid, and had a ...
Abstract 15778: Functional Genomics at the SYNE2 Gene Locus Associated With Atrial Fibrillation
Authors: Nana Liu, Jeffrey Hsu, John Barnard, David R Van Wagoner, Mina K Chung, Jonathan D Smith
Journal: Circulation (2018)

Introduction: Atrial fibrillation (AF) genetic studies identified a significant association for rs1152591, an intronic SNP in the SYNE2 gene encoding the nesprin-2 protein that connects the nuclear...
The association of increased levels of intermediate-density lipoproteins with smoking and with coronary artery disease.
Authors: GSteiner, LSchwartz, SShumak, MPoapst
Journal: Circulation (1987)

Studies were undertaken to determine whether there is an association between elevated levels of intermediate-density lipoproteins (IDL) (Sf 12-60 lipoproteins) and coronary artery disease. Forty-five to sixty-five-year-old men with objectively documented coronary artery disease (n = 58) who were free of known risk factors (diabetes, hypertension, obesity, hyperuricemia, and hypercholesterolemia) were compared with similar men who were free of coronary artery disease (n = 52). Smokers could not be excluded. The coronary artery disease group had a higher rate of cigarette smoking (NS, due to large variations); higher concentrations of triglycerides in their plasma (p = .003) and higher levels of very low-density lipoproteins (VLDL) (p = .007), IDL (p = .016), and low-density lipoproteins (LDL) (p = .04); as well as somewhat lower levels of high-density lipoprotein (HDL) cholesterol (p = .04). Chi-squared analysis demonstrated a strong association between coronary artery disease and IDL apolipoprotein (apo) ...
Measurement of renal perfusion and blood flow with fast computed tomography.
Authors: M DBentley, L OLerman, E AHoffman, M JFiksen-Olsen, E LRitman, J CRomero
Journal: Circulation Research (1994)

Fast computed tomography (CT) is one of the few methods available to measure cortical and medullary renal blood flow (RBF) directly. Because these measurements are complicated by passage of the contrast medium into extravascular compartments, we used the residual opacity following the vascular blush as an index to account for extravascular iohexol. Kidneys of anesthetized dogs were examined in situ by fast CT following intra-aortic injections of iohexol. Perfusion was analyzed during a control period and three subsequent periods in which RBF was reduced by 10%, 30%, and 50%. Cortical microvascular distribution volume changed from 19.7 +/- 2.8% to 19.8 +/- 1.7%, 15.3 +/- 1.2%, and 9.9 +/- 1.7%, respectively, without significant alterations in cortical mean transit time. Microvascular distribution volume was divided by mean transit time to determine tissue perfusion. Cortical perfusion changed from 3.8 +/- 0.7 to 3.9 +/- 0.6, 3.1 +/- 0.5, and 2.2 +/- 0.5 mL.min-1.mL tissue-1. Total cortical blood flow (cort...
Elevated 68Ga-FAPI Activity in Splenic Hemangioma and Pneumonia
Authors: Huipan Liu, Yingwei Wang, Wei Zhang, Liang Cai, Yue Chen
Journal: Clinical Nuclear Medicine (2021)

A 59-year-old woman with newly diagnosed pulmonary nodules underwent both 18F-FDG and 68Ga-FAPI PET/CT. Both studies showed similarly increased uptake in pneumonia. However, only 68Ga-FAPI PET/CT showed increased uptake in splenic hemangioma, whereas FDG uptake in the splenic lesion is low. Our case illustrates that splenic hemangioma can also reveal increased FAPI activity.
HCV genome-wide analysis for development of efficient culture systems and unravelling of antiviral resistance in genotype 4
Authors: Long V. Pham, Martin Schou Pedersen, Ulrik Fahnøe, Carlota Fernandez-Antunez, Daryl Humes, Kristian Schønning, Santseharay Ramirez, Jens Bukh
Journal: Gut (2021)

Objective HCV-genotype 4 infections are a major cause of liver diseases in the Middle East/Africa with certain subtypes associated with increased risk of direct-acting antiviral (DAA) treatment failures. We aimed at developing infectious genotype 4 cell culture systems to understand the evolutionary genetic landscapes of antiviral resistance, which can help preserve the future efficacy of DAA-based therapy. Design HCV recombinants were tested in liver-derived cells. Long-term coculture with DAAs served to induce antiviral-resistance phenotypes. Next-generation sequencing (NGS) of the entire HCV-coding sequence identified mutation networks. Resistance-associated substitutions (RAS) were studied using reverse-genetics. Result The in-vivo infectious ED43(4a) clone was adapted in Huh7.5 cells, using substitutions identified in ED43(Core-NS5A)/JFH1-chimeric viruses combined with selected NS5B-changes. NGS, and linkage analysis, permitted identification of multiple genetic branches emerging during culture adaptation, one of which had 31 substitutions leading to robust replication/propagation. Treatment of culture-adapted ED43 with nine clinically relevant protease-DAA, NS5A-DAA and NS5B-DAA led to complex dynamics of drug-target-specific RAS with coselection of genome-wide substitutions. Approved DAA combinations were efficient against the original virus, but not against variants with RAS in corresponding drug targets. However, retreatment with glecaprevir/pibrentasvir remained efficient against NS5A inhibitor and sofosbuvir resistant variants. Recombinants with specific RAS at NS3-156, NS5A-28, 30, 31 and 93 and NS5B-282 were viable, but NS3-A156M and NS5A-L30Δ (deletion) led to attenuated phenotypes. Conclusion Rapidly emerging complex evolutionary landscapes of mutations define the persistence of HCV-RASs conferring resistance levels leading to treatment failure in genotype 4. The high barrier to resistance of glecaprevir/pibrentasvir could prevent persistence and propagation of antiviral resistance.
Superficial Neoplasia Involving the Ileocecal Valve: Clinical Outcomes of Endoscopic Submucosal Dissection
Authors: G Andrisani, T Fukuchi, G Antonelli, J Hamanaka, G Costamagna, S Maeda, C Hassan, FM Di Matteo, K Hirasawa
Journal: Endoscopy (2021)

Aims Endoscopic submucosal dissection (ESD) is considered a first line treatment for colorectal superficial neoplasia, but certain anatomical locations are challenging even for skilled endoscopists. The Ileocecal valve (ICV) is considered a technically challenging site for ESD. Aim of this study was to analyse efficacy and safety of ESD in the treatment of colorectal neoplasia involving the ICV.
Acute impairment of endothelium-dependent relaxations to aggregating platelets following reperfusion injury in canine coronary arteries.
Authors: P JPearson, H VSchaff, P MVanhoutte
Journal: Circulation Research (1990)

Experiments were designed to determine whether endothelial injury contributes to augmented coronary vascular tone seen during myocardial reperfusion. Canine left anterior descending coronary arteries were exposed to ischemia followed by reperfusion (60 minutes each). Rings (3-4 mm) of the reperfused artery and of normal left circumflex (control) coronary artery segments were prepared. Rings were suspended for isometric force measurement in organ chambers containing modified Krebs' Ringer bicarbonate solution (37 degrees C, 95% O2-5% CO2). Endothelium-independent contractions to KCl and prostaglandin F2 alpha were unaltered after reperfusion. Endothelium-dependent relaxations to nitric oxide, sodium nitroprusside, and isoproterenol were comparable in control and reperfused arteries. However, reperfused coronary arteries contracted with prostaglandin F2 alpha lost the ability to express endothelium-dependent relaxations to aggregating platelets. Reperfused arterial rings also exhibited impaired endothelium-...
Porcine heart valves produce a protein that induces cell-mediated connective tissue degradation: II. Biochemical properties of the partially purified protein.
Authors: R SDecker, A MHenney, J TDingle
Journal: Circulation Research (1986)

A cardiac catabolic factor (CCF) has been partially purified from serum-free medium conditioned by minced porcine heart valves. CCF was prepared by a series of chromatographic techniques and compared directly with porcine synovial catabolin purified by the same protocol. CCF displayed a somewhat higher molecular weight (Mr 21,000) and isoelectric point (pI 5.2) than did synovial catabolin (Mr 18,000 and pI 4.8), but the two factors clearly resemble one another closely. CCF stimulated the release of glycosaminoglycans from cultured cartilage and mitral valve and provoked porcine valves to degrade their own collagen extracellular matrix. The release of hydroxyproline was inhibited by corticosteroids, whereas proteoglycan breakdown was not. Partially pure preparations of CCF and synovial catabolin stimulated murine thymocyte proliferation; moreover, that activity was almost totally abolished by an antibody raised against pure porcine interleukin-1. These observations suggest that CCF may represent a cataboli...
Effects of self-induced starvation on cardiac size and function in anorexia nervosa.
Authors: J SGottdiener, H AGross, W LHenry, J SBorer, M HEbert
Journal: Circulation (1978)

Cardiac size, function and rhythm were examined in 11 patients with anorexia nervosa. Mean left ventricular, left atrial and aortic dimensions on echocardiogram were below normal adult values at baseline. In addition to decreased cardiac dimensions--ventricular ectopy, relative hypotension, bradycardia and blunted heart rate--response to exercise were noted. Left ventricular systolic function, however, was unimpaired as indicated by normal echocardiographic fractional shortening, and by normal exercise augmentation of ejection fraction determined by radionuclide cineangiography. Eight of the patients responded to treatment with a mean weight gain of 32%. In these eight, cardiac dimensions increased toward normal: left ventricular dimension increased by 13%; left atrial dimension by 20%; aortic dimension by 15% and estimated left ventricular mass by 20%. We conclude that abnormalities of heart size and rhythm occur in patients with anorexia nervosa. However, cardiac dimensions, including left ventricular m...
Statistical analysis of pacemaker follow-up data. Rate stability and reliability.
Authors: G LGrunkemeier, J LDobbs, AStarr
Journal: Circulation (1976)

In a rate-stable pacemaker, pacemaker rate reflects battery voltage level and should remain constant or be slightly depleted with time in a linear fashion until failure occurs. Linear regression techniques are therefore particularly suited to the analysis of pacemaker rate data. Data on model 8114/8114A Starr-Edwards pacemakers followed at the University of Oregon Health Sciences Center were studied. For a given pacemaker both the slope of the regression line and the standard deviation about the regression line are proportional to the original rate. Natural indices of rate depletion and rate stability for each pacemaker can therefore be calculated by dividing the slope and the standard deviation, respectively, by the inpercept of the corresponding regression line. This model pacemaker has a small average standard deviation so that significant variations from the line of regression, indicating impending pulse generator failure, can be detected in spite of random fluctuations. Emergency and prophylactic rep...