tbuckley/cabot-search huggingface dataset:
The arm-ankle pressure gradient in relation to cardiovascular risk factors in intermittent claudication.
Authors: LJanzon, S EBergentz, B FEricsson, S ELindell
Journal: Circulation (1981)

The arm-ankle systolic pressure gradient was measured in 165 male patients with intermittent claudication and was correlated with different combinations of known cardiovascular risk factors. The pressure gradient increased with increasing number of risk factors. We conclude that intermittent claudication may be used as a simple model for studies of arteriosclerosis, the arm-ankle systolic pressure gradient being a measure of the degree of arteriosclerosis between heart and ankle.
Reduced baroreflex sensitivity with volume loading in conscious dogs.
Authors: S FVatner, D HBoettcher, G RHeyndrickx, R JMcRitchie
Journal: Circulation Research (1975)

The Bainbridge reflex, i.e., the effect of rapid saline infusion (1.1 +/- 0.1 liters) on heart rate and arterial and atrial blood pressures, was examined in 12 intact conscious dogs; mean arterial blood pressure rose by 33 +/- 3 (SE) mm Hg, mean atrial pressure by 14 +/- 1 mm Hg, and heart rate by 75 +/- 9 beats/min. After beta-receptor blockade, heart rate rose slightly less (+49 +/- 5 beats/min, P = 0.05). Cholinergic blockade, combined cholinergic and beta-receptor, or beta-receptor blockade after vagotomy blocked the heart rate response to the infusion. The rise in heart rate in the face of an increase in arterial blood pressure with volume loading suggested that the arterial baroreceptor reflex was not responding appropriately to the increase in arterial blood pressure. In conscious dogs after denervation of the arterial baroreceptors, the increase in heart rate with volume loading was no greater than that in those dogs with their arterial baroreceptors intact, suggesting that the baroreceptor reflex...
A mathematical model for the quantification of mitral regurgitation. Experimental validation in the canine model using contrast echocardiography.
Authors: J MDent, A RJayaweera, W PGlasheen, S PNolan, W DSpotnitz, F SVillanueva, SKaul
Journal: Circulation (1992)

BACKGROUNDBecause the clearance of contrast from the left atrium (LA) relative to the left ventricle (LV) depends on the degree of mitral regurgitation (MR), we hypothesized that a mathematical model can be developed that would provide a quantitative estimation of MR from the washout of contrast from these chambers.METHODS AND RESULTSAfter mathematically developing the model, we performed experiments in two groups of dogs with the use of contrast echocardiography. Group 1 consisted of nine dogs in which different degrees of MR were produced by creating ischemic LV dysfunction. Contrast was injected into the LV, and MR was graded visually on a scale of from 0 to 4+. Videointensity plots generated from the LA and LV were provided to the model. There was excellent correlation between visual assessment of MR and model-derived regurgitant fraction in the 33 stages: y = 0.16x + 0.002 (r = 0.97, p less than 0.001, SEE = 0.06). To obtain a more quantitative validation, we placed electromagnetic flow probes on the...
Pulsed ultraviolet laser irradiation produces endothelium-independent relaxation of vascular smooth muscle.
Authors: P GSteg, A JRongione, S TDeJesus, R HClarke, J MIsner
Journal: Circulation (1989)

Recent studies have shown that continuous wave laser irradiation induces contraction of vascular smooth muscle, except at powers far below the threshold for tissue ablation. To determine the corresponding effects of pulsed laser irradiation on vascular smooth muscle tone, vascular rings of rabbit thoracic aorta were mounted isometrically with 1 g tension in Krebs-bicarbonate buffer and irradiated with 308 or 351 nm from an excimer laser through a 400-microns optical fiber. A total of 250 exposures were performed with 1-6.5 mJ/pulse (fluence = 0.8-5.5 J/cm2), 10-50 Hz, and cumulative exposures of 10-120 seconds. Excimer laser irradiation in combinations of pulse energy (PE), repetition rate (RR), and cumulative exposure below, at, or above threshold for tissue ablation consistently produced relaxation unassociated with contraction in each of the 250 exposures. For the total 250 exposures, the magnitude of relaxation (reduction in recorded tension, Rmax) was 55 +/- 4% (mean +/- SEM) of maximum vasomotor rea...
Defibrillating shocks delivered to the heart impair efferent sympathetic responsiveness.
Authors: MIto, H PPride, D PZipes
Journal: Circulation (1993)

BACKGROUNDFunctional studies indicate that sympathetic efferents are located in the superficial subepicardium and vagal efferents are located in the subendocardium. It is possible that electrical shocks applied directly to the heart might affect the function of these autonomic nerves.METHODS AND RESULTSLow- (  10 J but not with shocks < or = 10 J, was ...
Impact of impinging wall jet on color Doppler quantification of mitral regurgitation.
Authors: C GChen, J DThomas, JAnconina, PHarrigan, LMueller, M HPicard, R ALevine, A EWeyman
Journal: Circulation (1991)

BACKGROUNDIn clinical color Doppler examinations, mitral regurgitant jets are often observed to impinge on the left atrial wall immediately beyond the mitral valve. In accordance with fluid dynamics theory, we hypothesized that a jet impinging on a wall would lose momentum more rapidly, undergo spatial distortion, and thus have a different observed jet area from that of a free jet with an identical flow rate.METHODS AND RESULTSTo test this hypothesis in vivo, we studied 44 patients with mitral regurgitation--30 with centrally directed free jets and 14 with eccentrically directed impinging wall jets. Maximal color jet areas (cm2) (with and without correction for left atrial size) were correlated with mitral regurgitant volumes, flow rates, and fractions derived from pulsed Doppler mitral and aortic forward flows. The groups were compared by analysis of covariance. Mean +/- SD mitral regurgitant fraction, regurgitant volume, and mean flow rate averaged 37 +/- 17%, 3.06 +/- 2.65 l/min, and 147 +/- 118 ml/sec...
Ventricular arrhythmias in trials of thrombolytic therapy for acute myocardial infarction. A meta-analysis.
Authors: S DSolomon, P MRidker, E MAntman
Journal: Circulation (1993)

BACKGROUNDAlthough thrombolytic therapy reduces long-term mortality in acute myocardial infarction, many clinicians remain concerned about an increased risk of ventricular arrhythmias associated with the use of these agents.METHODS AND RESULTSTo determine whether thrombolytic therapy increases the risk of ventricular tachyarrhythmias and whether an increase in arrhythmias could be responsible for the increased mortality seen in the first 24 hours after lytic therapy, we performed a meta-analysis of 15 randomized trials of thrombolysis in acute myocardial infarction in which the odds of developing in-hospital ventricular fibrillation (VF) and ventricular tachycardia (VT) in patients receiving thrombolysis was compared with that of patients receiving placebo. For trials that reported the incidence of VF during the first 6 hours after thrombolysis, the summary odds ratio for developing VF in the thrombolytic group was 0.98 (95% confidence interval [CI], 0.6 to 1.6; P = .94). For trials that reported the inci...
Myocardial blood flow during exercise in dogs with left ventricular hypertrophy produced by aortic banding and perinephritic hypertension.
Authors: R JBache, X ZDai, DAlyono, T RVrobel, D CHomans
Journal: Circulation (1987)

This study tested the hypothesis that for similar degrees of left ventricular hypertrophy, subendocardial blood flow would be facilitated by the increased diastolic coronary perfusion pressure associated with arterial hypertension, as compared with hypertrophy produced by banding the ascending aorta. Left ventricular hypertrophy was produced with perinephritic hypertension in seven adult dogs and by banding the ascending aorta in nine adult dogs. Left ventricular/body weight ratios were 6.15 +/- 0.59 g/kg in the hypertensive animals and 6.87 +/- 0.47 g/kg in dogs with aortic banding, as compared with 4.23 +/- 0.23 g/kg in seven normal dogs (p less than .01). Studies were performed at rest and during two stages of treadmill exercise to achieve heart rates of 195 and 260 beats/min. Diastolic aortic pressure was increased in animals with hypertension but not in dogs with aortic banding. Systolic ejection period was prolonged in dogs with aortic banding but not in hypertensive dogs. Mean blood flow per gram o...
An overview of randomized trials of rehabilitation with exercise after myocardial infarction.
Authors: G TO'Connor, J EBuring, SYusuf, S ZGoldhaber, E MOlmstead, R SPaffenbarger, C HHennekens
Journal: Circulation (1989)

Of 22 randomized trials of rehabilitation with exercise after myocardial infarction (MI), one trial had results that achieved conventional statistical significance. To determine whether or not these studies, in the aggregate, show a significant benefit of rehabilitation after myocardial infarction, we performed an overview of all randomized trials, involving 4,554 patients; we evaluated total and cardiovascular mortality, sudden death, and fatal and nonfatal reinfarction. For each endpoint, we calculated an odds ratio (OR) and 95% confidence interval (95% CI) for the trials combined. After an average of 3 years of follow-up, the ORs were significantly lower in the rehabilitation than in the comparison group: specifically, total mortality (OR = 0.80 [0.66, 0.96]), cardiovascular mortality (OR = 0.78 [0.63, 0.96]), and fatal reinfarction (OR = 0.75 [0.59, 0.95]). The OR for sudden death was significantly lower in the rehabilitation than in the comparison group at 1 year (OR = 0.63 [0.41, 0.97]). The data we...
Acetylcholine-induced coronary vasoconstriction and vasodilation in tranquilized baboons.
Authors: D RKnight, Y TShen, M AYoung, S FVatner
Journal: Circulation Research (1991)

To determine the effects of acetylcholine on the coronary bed in the baboon and whether the effects preceded or followed the action of acetylcholine on ventricular function, eight adult baboons (Papio anubis) were instrumented to measure left ventricular (LV) and mean arterial pressures, LV dP/dt, regional myocardial function, and coronary blood flow. Acetylcholine was injected locally through a catheter positioned in the coronary artery ostium using fluoroscopic guidance in intact sedated baboons. With heart rate held constant, intracoronary acetylcholine (0.5 micrograms/kg) reduced coronary blood flow by 82 +/- 4% from a baseline value of 34 +/- 4 ml/min without a significant change in mean arterial pressure and with a reduction in LV dP/dt of only 12 +/- 3%. The decrease in coronary blood flow occurred before either LV dP/dt or regional myocardial function fell in the region of the heart receiving acetylcholine. After the intense coronary constriction, a later phase characterized by dilation was observ...
Multiple Primary Osseous B-Lymphoblastic Lymphoma/Leukemia Shown on Bone Scintigraphy
Authors: Ming Wen, Xiao-Juan Peng, Jian-Min Huang, Ling-Ge Wei, Peng Xie
Journal: Clinical Nuclear Medicine (2021)

Abstract Primary osseous B-lymphoblastic lymphoma/leukemia is very rare, especially multiple bones involved. Herein, we reported the bone scintigraphy findings in a 16-year-old adolescent boy with a 20-day history of right thigh pain caused by B-lymphoblastic lymphoma/leukemia. Multiple abnormal MDP-avid foci were noted on 99m Tc-MDP bone scintigraphy. Interestingly, the CT images of corresponding lesions were unrevealing. Finally, the B-lymphoblastic lymphoma/leukemia was confirmed by pathology and immunohistochemistry.
Passive electrical properties, mechanical activity, and extracellular potassium in arterially perfused and ischemic rabbit ventricular muscle. Effects of calcium entry blockade or hypocalcemia.
Authors: W ECascio, G XYan, A GKléber
Journal: Circulation Research (1990)

The relation among passive electrical resistive properties, longitudinal conduction velocity, extracellular potassium concentration, [K+]o, and mechanical activity was investigated in the isolated rabbit papillary muscle during normal arterial perfusion and no-flow ischemia in the presence and absence of verapamil, or a reduced extracellular Ca2+ concentration [Ca2+]o. During normal arterial perfusion, verapamil (0.5 microM, free [Ca2+]o = 1.0 mM) and hypocalcemic blood perfusate (free [Ca2+]o = 0.4 mM) reduced the maximal isometric twitch tension by 48% and 78%, depolarized the resting membrane by +3 and +7 mV, decreased the extracellular longitudinal resistance (ro) by 15% and 26%, and increased conduction velocity by 4% and 6%, respectively. The changes in conduction velocity during these interventions were consistent with those predicted by linear cable theory (+3% and +9%) for the observed changes in ro. In contrast, verapamil shortened whereas a reduced [Ca2+]o lengthened action potential duration. ...
106P Predicting response to pembrolizumab in metastatic non-small cell lung cancer (NSCLC): Clinical usefulness of peripheral lymphocyte-monocyte ratio and baseline FDG-uptake
Authors: L. Raimondi, M. Montebello, F. Corica, P. Ciracì, G.P. Spinelli
Journal: Journal of Thoracic Oncology (2021)
Role of Cholangioscopy in The Longitudinal Spreading Assessment of Biliar Intraepithelial Neoplasia
Authors: N Torres Monclús, E Pijoan Comas, M Alburquerque, A Vargas Garcia, G Torres Vicente, I Miguel Salas, DC Bayas Pástor, N Zaragoza Velasco, JM Reñé Espinet, F González-Huix Lladó
Journal: Endoscopy (2021)

A 67-year-old man underwent ERCP for choledocolithiasis and dilated CBD-10mm. A 6-7mm round defect in middle CBD, fixed and unremovable with balloon catheter, was found. Sphincterotomy and extraction of biliary sludge and adenomatous like tissue sphacelus were performed. Brush-citology and intraductal-forceps-biopsy reported intraepithelial adenocarcinoma with microinfiltration.
Certain beta-blockers can decrease beta-adrenergic receptor number: II. Down-regulation of receptor number by alprenolol and propranolol in cultured lymphoma and muscle cells.
Authors: R JHughes, L CMahan, P AInsel
Journal: Circulation Research (1988)

We have used two different cultured cell lines--S49 lymphoma cells and BC3H-1 muscle cells--to examine the regulation of beta-adrenergic receptors by receptor antagonists. Rather than an increase (up-regulation) of receptor number that such antagonists often produce, we found that certain beta-blockers elicit a decrease (down-regulation) of beta-adrenergic receptors. Alprenolol and propranolol, but not sotalol or ICI 118,551, at concentrations of 10-100 nM down-regulated beta-adrenergic receptors 20-70% following 16-20 hours of treatment of S49 or BC3H-1 cells. Several observations suggest that this phenomenon depends upon beta-receptor interaction, including stereoselectivity [(-)-enantiomers more potent than (+)-enantiomers], blockade of the effect by ICI 118,551, absence of down-regulation of alpha-adrenergic receptors in BC3H-1 cells, and lack of a decrease in beta-adrenergic receptor-independent (forskolin-stimulated) cyclic AMP accumulation in S49 cells. The possibility of retained antagonist in...
Phospholamban and troponin I are substrates for protein kinase C in vitro but not in intact beating guinea pig hearts.
Authors: E GKranias
Journal: Circulation Research (1990)

The incorporation of [32P]inorganic phosphate into membranous, myofibrillar, and cytosolic proteins was studied in Langendorff-perfused guinea pig hearts treated with phorbol 12-myristate 13-acetate (PMA) or 1,2-dioctanoylglycerol (D8G), which are potent activators of protein kinase C. Control hearts were perfused with an inactive phorbol ester (4 alpha-phorbol 12,13-didecanoate), which does not cause activation of protein kinase C. To ensure the blockade of different receptor systems, the perfusions were carried out in the presence of prazosin, propranolol, and atropine. Perfusion of hearts with either PMA (4 microM) or D8G (200 microM) was associated with a negative effect on left ventricular inotropy and relaxation. Examination of the 32P incorporation into various fractions revealed that there were no increases in the degree of phosphorylation of phospholamban in sarcoplasmic reticulum, and troponin I and C protein in the myofibrils, although these proteins were found to be substrates for protein kina...
A model study of volume conductor effects on endocardial and intracavitary potentials.
Authors: D SKhoury, YRudy
Journal: Circulation Research (1992)

An idealized mathematical model was developed to study the effects of variations in conductive and geometric parameters on measured endocardial and intracavitary potentials. The model consists of a spherical multielectrode probe located eccentrically within a system of concentric spheres that represent a blood cavity, myocardium, lung region, and surface muscle layer. Solutions were found for endocardial and intracavitary probe potentials produced by two different configurations of equivalent myocardial sources: 1) multiple activation wave fronts oriented radially, representing global fronts in the myocardium; and 2) pairs of equal and opposite dipoles on a line oriented tangentially to the endocardial surface, representing cardiac sources during early ectopic activation. It was found that the complexities of the cardiac source configurations are reflected in the endocardial potential but not in the associated probe potential, which exhibits a smoothed-out, low-amplitude distribution. In addition, probe p...
Safety of Gastrointestinal Endoscopy During the Second Wave of Covid-19 Pandemic: A Single Tertiary Centre Prospective Study
Authors: O Aoko, H Yousuf, N Humphreys, D O’Sullivan, M Alenezi, R Varley, R Saeidi, K Boland, J Ryan, A O’Toole, G Harewood, S Patchett, D Cheriyan
Journal: Endoscopy (2021)

Aims To determine the incidence of COVID-19 transmission following outpatient gastrointestinal (GI) endoscopy during rising community incidence of COVID-19.
The stimulation of cardiac prostaglandin production by blood plasma and its relationship to the regulation of coronary flow in isolated isovolumic rabbit hearts.
Authors: R LMoretti, SAbraham, R REcker
Journal: Circulation Research (1976)

Infusion of small amounts of blood plasma into isolated, isovolumic rabbit hearts perfused with Tyrode's solution resulted in coronary vasoconstriction followed by a decrease in left ventricular developed pressure and dP/dt. Maximal effects were obtained with a perfusate plasma concentration of 1%. Increasing the plasma concentration beyond 1% did not appreciably increase the coronary vasoconstriction. During perfusion with 2% plasma, the coronary flow-oxygen uptake ratio was unchanged over a range of perfusion pressures (40-100 mm Hg) and vascular resistance increased with pressure. In the absence of plasma, the coronary flow-oxygen uptake ratio increased with pressure and vascular resistance decreased. Thus, cardiac regulation of coronary flow in response to changes in perfusion pressure occurred in the presence of plasma but not in its absence. The effects of plasma were reduced with two different inhibitors of prostaglandin synthesis (5,9,11,14-eicosatetraynoic acid and indomethacin). At a perfusate c...
Abstract 12529: Prognostic Value of the Combination of Model of End-Stage Liver Disease Score and Non-Alcoholic Fatty Liver Disease Fibrosis Score in Patients Admitted for Acute Decompensated Heart Failure
Authors: Masatsugu Kawahira, Takahisa Yamada, Takashi Morita, Yoshio Furukawa, Shunsuke Tamaki, Yusuke Iwasaki, Masato Kawasaki, Atsushi Kikuchi, Tsutomu Kawai, Masahiro Seo, Makoto Abe, Jun Nakamura, Kyoko Yamamoto, Kiyomi Kayama, Kazuya Tanabe, Masatake Fukunami
Journal: Circulation (2018)

Background: Cardiohepatic interactions have been a focus of attention in heart failure, and the model of end-stage liver disease (MELD), a robust scoring system of liver dysfunction, has been shown...
Inhibition of feline collateral vessel development following experimental thrombolic occlusion.
Authors: R GSchaub, K MMeyers, R DSande, GHamilton
Journal: Circulation Research (1976)

We compared development of feline hindlimb collateral circulation after acute occlusion of the terminal aorta by ligation, thrombus formation, and formation of a closed aortic loop containing thromboplastin. Collateral circulation development was assessed by aortograms, scintillation scans, neurological signs following occlusion, measurement of hindlimb muscle blood flow, and forelimb and hindlimb temperature. In cats in which aortic occlusion was the result of ligation or thromboplastin in the aortic loop, paralysis was not evident. Aortograms and scintillation scans indicated hindlimb blood flow. Both muscle temperature and blood flow data indicated that the return of blood flow was rapid. The 5th lumbar artery appears to be the origin of the collateral vessels. The mid-zone component is a dorsal and ventral vertebral route and an epaxial muscle route. The reentry components are the 6th or 7th lumbar arteries. The collateral vessels arise from preexisting collateral vessels. Of those cats in which aor...
Endothelial modulation of the ouabain-induced contraction in human placental vessels.
Authors: C FSánchez-Ferrer, M SFernández-Alfonso, APonte, M ACasado, RGonzález, LRodríguez-Mañas, APareja, JMarín
Journal: Circulation Research (1992)

Ouabain (1 x 10(-7)-3 x 10(-5) M) elicited concentration-dependent vasoconstriction in human placental arteries and veins. These responses, but not those produced by 10(-6) M 5-hydroxytryptamine, were increased after the removal of vascular endothelium. In placental arteries, the respective blockade of cyclooxygenase or lipoxygenase with indomethacin of 5,8,11,15-eicosatetraynoic acid as well as the inactivation of nitric oxide with phenidone or oxyhemoglobin and the inhibition of nitric oxide synthesis with NG-monomethyl L-arginine (all at 10(-5) M) did not mimic the effects of endothelial denudation on ouabain-evoked contractions. Bioassay experiments suggested that the above-mentioned endothelial effects are mediated by diffusible factors. 86Rb+ uptake, a method to measure sodium pump activity, was significantly reduced by the removal of endothelium. These results suggest the existence of an inhibitory modulation by the endothelium of the contractions induced by ouabain, likely mediated by a diffusible...
Stimulation of phospholipid N-methylation by isoproterenol in rat hearts.
Authors: YTaira, VPanagia, K RShah, R EBeamish, N SDhalla
Journal: Circulation Research (1990)

Phosphatidylethanolamine (PtdEtn) N-methyltransferase activities were studied in rat heart sarcolemmal and sarcoplasmic reticular fractions after a single intraperitoneal injection of isoproterenol (0.5-5.0 mg/kg). Three active sites (I, II, and III) for PtdEtn N-methylation were assayed by measurement of [3H]methyl group incorporation from 0.055, 10, and 150 microM S-adenosyl-L-[methyl-3H]methionine into membrane PtdEtn molecules. Total methylation activity for catalytic site I of both sarcolemma and sarcoplasmic reticulum was stimulated within 2 minutes by isoproterenol in a dose-dependent manner. Although the increased methyltransferase activity in sarcoplasmic reticulum was normalized at 10 minutes, the enzyme activity in sarcolemma was normalized at 5 minutes but was again increased at 10-30 minutes after isoproterenol injection. No changes in response to isoproterenol were seen for site II and III N-methylation activities in either membrane. Individual N-methylated phospholipids (phosphatidyl-N-mono...