tbuckley/cabot-search huggingface dataset:
Reversible alterations in excitation-contraction coupling during myocardial hypertrophy in rat papillary muscle.
Authors: J MCapasso, R SAronson, E HSonnenblick
Journal: Circulation Research (1982)

To investigate the possible role of an alteration in excitation-contraction coupling in cardiac hypertrophy, we compared simultaneously recorded action potentials along with isometric or isotonic contractions of normal and hypertrophied papillary muscles. Hypertrophy was produced by renal hypertension in rats. Hypertrophied papillary muscles were taken from rats that had been hypertensive for 10 [HBP (10)] or 20 [HBP (20)] weeks. Regression of changes induced by hypertrophy was studied in rats that had been hypertensive for 10 weeks and then made normotensive for 10 weeks by removal of the ischemic kidney. Papillary muscles from age-matched, sham-operated rats [SHAM (10), SHAM (20)] were used as controls. We found that HBP (10) rats had significantly longer action potentials than SHAM (10) rats and that difference in the action potential duration recorded during isotonic and isometric contractions was significantly different from SHAM (10) and HBP (10) rats. Peak developed tension was the same in HBP (10)...
Lower limit of cerebral blood flow autoregulation in experimental renovascular hypertension in the baboon.
Authors: J VJones, WFitch, E TMacKenzie, SStrandgaard, A MHarper
Journal: Circulation Research (1976)

The effect of chronic renovascular hypertension on the autoregulation of cerebral blood flow was studied in anesthetized baboons. Cerebral blood flow was measured by the intracarotid 133Xe clearance method. Six baboons with renal hypertension of 8-12 weeks' duration were compared with six normotensive controls. The lower limit of autoregulation was determined following controlled hemorrhage. In the initially normotensive baboons, cerebral blood flow remained constant until mean arterial pressure had decreased to the range of 45-59 mm Hg. Thereafter, cerebral blood flow decreased with each further decrease in mean arterial pressure. In the chronically hypertensive baboons cerebral blood flow autoregulated until the mean arterial pressure had decreased to the range of 75-89 mm Hg. Therefore, the lower limit of autoregulation of cerebral blood flow was shifted to higher absolute levels of mean arterial pressure in baboons with chronic renovascular hypertension presumably due to adaptive changes in the cerebr...
Aggregating human platelets in carotid sinus of rabbits decrease sensitivity of baroreceptors.
Authors: ZLi, F MAbboud, M WChapleau
Journal: Circulation Research (1992)

Aggregating platelets release factors that act in a local paracrine manner to alter vascular tone. The purpose of the present study was to explore the possibility that factors released from aggregating platelets may alter the sensitivity of arterial baroreceptors. Baroreceptor activity was recorded from the vascularly isolated carotid sinus of rabbits anesthetized with sodium pentobarbital. The carotid sinus was filled with oxygenated Krebs-Henseleit buffer and distended with slow ramp increases in nonpulsatile pressure. Sensitivity of baroreceptors to increased pressure was determined before and during intraluminal exposure of the sinus to washed human platelets suspended in Krebs' buffer. Platelets activated with thrombin (0.4 units/ml) decreased baroreceptor activity and the slope of the pressure-activity curve significantly (n = 6). The platelet-induced decrease in baroreceptor sensitivity was related to the duration of exposure to platelets with no change in baroreceptor activity after 4 minutes and ...
Differential Effects of Cream, Glucose, and Orange Juice on Inflammation, Endotoxin, and the Expression of Toll-Like Receptor-4 and Suppressor of Cytokine Signaling-3.
Authors: Rupali) Deopurkar, Ghanim (Husam), Friedman (Jay), Abuaysheh (Sanaa)
Journal: Diabetes Care (2010)
Reconsideration of criteria for the Fontan operation. Influence of pulmonary artery size on postoperative hemodynamics of the Fontan operation.
Authors: H Senzaki, T Isoda, A Ishizawa, T Hishi
Journal: Circulation (1994)

BACKGROUND The outcome of the Fontan operation largely depends on the selection of patients because this procedure is a physiological correction. Among the several selection criteria for the Fontan operation, the importance of adequate size of the pulmonary artery remains controversial. In this series, in order to clarify whether the pulmonary artery size is indispensable or not as one of the selection criteria for the Fontan operation, we considered the physiological meaning of pulmonary artery size and investigated how it influenced postoperative hemodynamics of the Fontan operation. METHODS AND RESULTS In congenital heart disease of decreasing pulmonary blood flow, 40 patients were examined for this analysis. Pulmonary artery indexes (cross-sectional area of the right and left pulmonary arteries divided by body surface area) were measured as the expression of pulmonary artery size, and the relations of pulmonary artery index (PAI) to pulmonary vascular resistance (Rp) and compliance (Cp) were studied. There was no significant correlation between PAI and Rp, whereas a significant correlation was found between PAI and Cp (r = .71, P = .001). Furthermore, Cp influenced postoperative hemodynamics of the Fontan operation by affecting the peak central venous pressure (pCVP) and total impedance, which was the afterload to the ventricle. Impedance increased abruptly when PAI was &lt; approximately 100 mm2/m2. CONCLUSIONS The smaller pulmonary artery size causes more disadvantageous hemodynamics after the Fontan operation, with resultant effects of the rise in pCVP and the increase in afterload to the single ventricle.
Prediction of severe immune-related adverse events requiring hospital admission in patients on immune checkpoint inhibitors: study of a population level insurance claims database from the USA
Authors: Mark Kalinich, William Murphy, Shannon Wongvibulsin, Vartan Pahalyants, Kun-Hsing Yu, Chenyue Lu, Feicheng Wang, Leyre Zubiri, Vivek Naranbhai, Alexander Gusev, Shawn G Kwatra, Kerry L Reynolds, Yevgeniy R Semenov
Journal: Journal for ImmunoTherapy of Cancer (2021)

Immune-related adverse events (irAEs) are a serious side effect of immune checkpoint inhibitor (ICI) therapy for patients with advanced cancer. Currently, predisposing risk factors are undefined but understanding which patients are at increased risk for irAEs severe enough to require hospitalization would be beneficial to tailor treatment selection and monitoring.
Changes in cholinergic parameters associated with failure of conotruncal septation in embryonic chick hearts after neural crest ablation.
Authors: M LKirby, R SAronstam, J JBuccafusco
Journal: Circulation Research (1985)

Cells from the neural crest over occipital somites migrate to the heart, where they give rise to parasympathetic postganglionic neurons as well as ectomesenchymal elements which contribute to conotruncal septation. With a microcautery needle, the neural crest over occipital somites was ablated bilaterally in chicken embryos at an early stage of development. Histological examination on incubation day 15 revealed conotruncal malformations, involving malformation or absence of the conotruncal septum in all embryos. Two peaks of embryo mortality were observed. One peak (incubation days 6-8) occurred at the same time as conotruncal septal closure; the second peak (incubation days 11-13) was concurrent with the onset of functional parasympathetic innervation. A disruption of parasympathetic innervation was indicated by: (1) a decrease in acetylcholinesterase staining, (2) a decrease (27%) in the number of ganglion cells in the conotruncus, (3) decreases in the acetylcholine content of atrium (31%) and ventricle...
Letter by Andreotti et al Regarding Article, “Hemoglobin Level, Chronic Kidney Disease, and the Risks of Death and Hospitalization in Adults With Chronic Heart Failure: The Anemia in Chronic Heart Failure: Outcomes and Resource Utilization (ANCHOR) Study”
Authors: Felicita Andreotti, Giulio Coluzzi, Filippo Crea
Journal: Circulation (2007)
Inotropic response to norepinephrine is augmented early and maintained late in conscious dogs with perinephritic hypertension.
Authors: R PShannon, R JGelpi, LHittinger, D EVatner, C JHomcy, R MGraham, S FVatner
Journal: Circulation Research (1991)

We studied the inotropic responses to intravenous infusions of norepinephrine in nine conscious chronically instrumented dogs before and early (2-4 weeks) in the development of perinephritic hypertension; seven conscious dogs were studied later (approximately 14 weeks), during a more stable phase of hypertension. perinephritic hypertension was associated with a 24% increase in left ventricular (LV) mass during developing hypertension; no further increase was seen during the stable hypertension phase. LV end-systolic stress was increased early (p less than 0.01) but was normalized later. The LV end-systolic stress-volume relation demonstrated an enhanced contractile response to norepinephrine during developing hypertension, which returned toward control later in the course of stable hypertension. The LV dP/dt responses to norepinephrine (0.4 microgram/kg/min) were significantly greater during developing hypertension (7,509 +/- 337 mm Hg/sec, p less than 0.05) compared with the control period (4,737 +/- 286...
Correction to: LMTK3 inhibition affects microtubule Stability
Authors: Chiara Cilibrasi, Angeliki Ditsiou, Athanasios Papakyriakou, George Mavridis, Murat Eravci, Justin Stebbing, Teresa Gagliano, Georgios Giamas
Journal: Molecular Cancer (2021)

An amendment to this paper has been published and can be accessed via the original article.
Antiphospholipid Antibodies and Risk for Recurrent Vascular Events
Authors: Antonio R Cabral
Journal: JAMA (2004)

Our website uses cookies to enhance your experience. By continuing to use our site, or clicking "Continue," you are agreeing to our Cookie Policy | Continue JAMA HomeNew OnlineCurrent IssueFor Authors Publications JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry (1919-1959) Podcasts Clinical Reviews Editors' Summary Medical News Author Interviews More JN Learning / CMESubscribeJobsInstitutions / LibrariansReprints & Permissions Terms of Use | Privacy Policy | Accessibility Statement 2023 American Medical Association. All Rights Reserved Search All JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Forum Archive JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry Input Search Term Sign In Individual Sign In Sign inCreate an Account Access through your institution Sign In Purchase Options: Buy this article Rent this article Subscribe to the JAMA journal
Measurement of regional myocardial perfusion and mass by subselective hydrogen infusion and washout techniques: a validation study.
Authors: C LGrines, G BMancini, M JMcGillem, K PGallagher, R AVogel
Journal: Circulation (1987)

A technique was developed for measuring regional myocardial perfusion by intracoronary infusions of hydrogen (H2)-saturated saline. H2 concentration was detected during washout in the pulmonary artery by means of the voltage response of a platinum-tipped electrode. Regional myocardial perfusion was calculated from the H2 exponential desaturation curve according to the Kety-Schmidt principle. In 16 anesthetized open-chest dogs, validation of this technique was performed at baseline, reduced (stenosis), and hyperemic (dipyridamole) flow states by means of the radionuclide-labeled microsphere reference withdrawal technique. There was an excellent quadratic correlation between microsphere and H2 washout techniques (range 0.11 to 3.15 ml/min/g) (n = 33, r = .92, y = -0.12x2 + 0.89x + 0.20, SEE = 0.20 ml/min/g; p less than .0001). Hyperemic regional myocardial perfusion was underestimated by H2 washout and severely ischemic regional myocardial perfusion was overestimated. When regional myocardial perfusion valu...
Vascular prostacyclin is increased in patients ingesting omega-3 polyunsaturated fatty acids before coronary artery bypass graft surgery.
Authors: RDeCaterina, DGiannessi, AMazzone, WBernini, GLazzerini, SMaffei, MCerri, LSalvatore, BWeksler
Journal: Circulation (1990)

Interest in the antithrombotic potential of diets enriched with fish oil-derived polyunsaturated fatty acids (omega-3 PUFAs) prompted us to examine how these fatty acids, when taken preoperatively, affect hemostasis, plasma lipid levels, and production of prostacyclin (PGI2) by vascular tissues in atherosclerotic patients undergoing coronary artery bypass graft surgery. Fifteen patients with angiographically proven coronary artery disease received 3 g/day eicosapentaenoic acid and 1.3 g/day docosahexaenoic acid as capsules of purified fish oil for 28 days before surgery. Platelet aggregation induced by low concentrations of ADP, collagen, and epinephrine decreased (p less than 0.05) and serum thromboxane B2 decreased 36% (p less than 0.01) from baseline values. Bleeding times increased 40% (p less than 0.01) from baseline. Serum triglycerides decreased 50% (p less than 0.05) without a change in total serum cholesterol. Spontaneous production of PGI2 measured as 6-ketoprostaglandin F1 alpha (6-keto-PGF1 al...
Continuous measurement of left ventricular performance during and after maximal isometric deadlift exercise.
Authors: JSullivan, PHanson, P SRahko, J DFolts
Journal: Circulation (1992)

BACKGROUNDIsometric exercise produces a reflex increase in arterial blood pressure that is proportional to the intensity and mass of muscle used during contraction. Little is known about the transient effects of heavy weight lifting on left ventricular performance. In this study, we measured continuous changes in left ventricular performance during maximal large-muscle isometric exercise using the standing deadlift position.METHODS AND RESULTSTen healthy young men performed serial deadlifts at 50% of maximal voluntary effort for 90 seconds and 100% of maximal effort for 30 seconds. Echocardiographic imaging (apical four-chamber view), arterial blood pressure (brachial artery catheter), and electrocardiographic monitoring were recorded throughout the deadlift and for 30 seconds of recovery. Aortic flow velocity was also monitored during a separate series of deadlifts. During 100% maximal deadlift, mean arterial pressure increased from 108 +/- 4 to 164 +/- 6 mm Hg. Left ventricular ejection fraction decline...
Morphometry of pinocytotic vesicles in the capillary endothelium of rabbit lungs using automated equipment.
Authors: JGil, D ASilage
Journal: Circulation Research (1980)

Pinocytotic vesicles are one of several anatomic factors relevant to the permeability for macromolecules of capillary endothelia. We quantitified the number and distribution of pinocytotic vesicles present in the endothelium of pulmonary capillaries. Several similar studies have been reported in the past for endothelia of systemic capillaries, but the technical difficulties involved in this difficult application of morphometry never have been discussed. In the present work, an on-line microprocessor was used to assist with the processing of the point-counting data. The average figures from nine rabbit lungs for parameters thought to be relevant to characterize the population of vesicles are: thickness of the endothelium (TAUen) 0.192 microns; number of vesicles per volume unit of cell (NVen), 131 vesicles/microns3; vesicular load of each cell front (N/S)b, 196 vesicle/microns2, and (N/S)i, 181 vesicles/microns2. The number of vesicles per volume unit (NVen) is smaller than that which has been described fo...
In Reply
Authors: Rainer Porschen, Hendrik-Tobias Arkenau, Stefan Kubicka, Richard Greil, Thomas Seufferlein, Werner Freier, Albrecht Kretzschmar, Ullrich Graeven, Axel Grothey, Axel Hinke, Wolff Schmiegel, Hans-Joachim Schmoll
Journal: Journal of Clinical Oncology (2007)
Spectral energy of the first heart sound in acute myocardial ischemia. A correlation with electrocardiographic, hemodynamic, and wall motion abnormalities.
Authors: W BClarke, S MAustin, P MShah, P MGriffin, J TDove, JMcCullough, B FSchreiner
Journal: Circulation (1978)

First heart sound (S1) energy spectra in isovolumic systole, hemodynamics, and angiographic left ventricular wall motion (LVWM) at rest and with atrial pacing were compared in 27 patients who underwent diagnostic cardiac catheterization and angiography because of chest pain. Eighteen patients were found to have coronary artery disease (CAD) and nine patients, normal coronary arteries. Eleven of the 18 CAD patients (61%) had a mean reduction in the spectral energy of S1 of 6.5 +/- 1.4 (SEM) dB below control (-52%), during interruption of ischemic stress of rapid atrial pacing, compared to only one of nine patients without CAD (P less than 0.05). Only five CAD patients (28%) had an abnormal rise (greater than or equal to 5 mm) in left ventricular end-diastolic pressure (LVEDP) either during or upon interruption of pacing, and six (33%) had ischemic ST-segment depression greater than or equal to mv in the ECG. Similarly two patients free of CAD (22%) had an abnormal increase in LVEDP, and none had ECG eviden...
The risks of risk adjustment
Authors: L I Iezzoni
Journal: JAMA (1997)

Risk adjustment is essential before comparing patient outcomes across hospitals. Hospital report cards around the country use different risk adjustment methods.To examine the history and current practices of risk adjusting hospital death rates and consider the implications for using risk-adjusted mortality comparisons to assess quality.This article examines severity measures used in states and regions to produce comparisons of risk-adjusted hospital death rates. Detailed results are presented from a study comparing current commercial severity measures using a single database. It included adults admitted for acute myocardial infarction (n=11880), coronary artery bypass graft surgery (n=7765), pneumonia (n=18016), and stroke (n=9407). Logistic regressions within each condition predicted in-hospital death using severity scores. Odds ratios for in-hospital death were compared across pairs of severity measures. For each hospital, z scores compared actual and expected death rates.The severity measure called Disease Staging had the highest c statistic (which measures how well a severity measure discriminates between patients who lived and those who died) for acute myocardial infarction, 0.86; the measure called All Patient Refined Diagnosis Related Groups had the highest for coronary artery bypass graft surgery, 0.83; and the measure, MedisGroups, had the highest for pneumonia, 0.85 and stroke, 0.87. Different severity measures predicted different probabilities of death for many patients. Severity measures frequently disagreed about which hospitals had particularly low or high z scores. Agreement in identifying low- and high-mortality hospitals between severity-adjusted and unadjusted death rates was often better than agreement between severity measures.Severity does not explain differences in death rates across hospitals. Different severity measures frequently produce different impressions about relative hospital performance. Severity-adjusted mortality rates alone are unlikely to isolate quality differences across hospitals.
Two-dimensional left ventricular deformation during systole using magnetic resonance imaging with spatial modulation of magnetization.
Authors: A AYoung, HImai, C NChang, LAxel
Journal: Circulation (1994)

BACKGROUNDMyocardial tissue tagging with the use of magnetic resonance imaging allows noninvasive regional analysis of heart wall motion and deformation. However, any evaluation of the effect of disease or treatment requires a baseline reference of normal values and variation. We studied the two-dimensional motion of material points imaged within the left ventricular wall using spatial modulation of magnetization (SPAMM) in 12 normal human volunteers.METHODS AND RESULTSFive parallel short-axis and five parallel long-axis slices were acquired at five times during systole. SPAMM tags were generated at end diastole using a 7-mm grid. Intersection point data were analyzed for displacement, rotation, and torsion, and triangles of points were analyzed for local rotation and principal strains. Short-axis displacement was the least in the septum for all longitudinal levels (P < .001). Torsion about the long axis was uniform circumferentially because of the motion of the centroids used to reference the rotation. I...
The role of arterial baroreceptors in mediating the cardiovascular response to a cardiac glycoside in conscious dogs.
Authors: R JMcRitchie, S FVatner
Journal: Circulation Research (1976)

To determine the role of the arterial baroreceptor reflex in mediating the cardiovascular response to a cardiac glycoside, we examined the effects of ouabain (G-strophanthin), 17.5 mug/kg, iv, on direct and continuous measurements of left ventricular diameters, pressures, velocity of shortening, (dP/dt)/P, arterial pressure, cardiac output, and total peripheral resistance. These studies were conducted on healthy conscious dogs before and after total arterial baroreceptor denervation (TABD). Maximal pressor effects were observed in the first 3-5 minutes; mean arterial pressure increased by 11 +/- 1 mm Hg in normal dogs compared to 33 +/- 4 mm Hg in denervated dogs. In intact dogs at this time heart rate decreased by 18 +/- 2 beats/min and cardiac output fell by 18 +/- 3%; these values gradually returned toward control over 15-30 minutes. When heart rate was kept constant, cardiac output did not fall after injection of ouabain. In contrast, heart rate and cardiac output did not change significantly after ou...
Body Mass Index as a Potential Confounder for Oncological Outcomes Following Autologous Fat Transfer—Reply
Authors: Todor K. Krastev, Arjen van Turnhout, René van der Hulst
Journal: JAMA Surgery (2019)

In Reply We have carefully read the comments of Quinn et al regarding our recently published article.1 The authors propose that body mass index (BMI) could be a potential confounder to account for the differences in mortality found in our study.
Color Doppler evaluation of aortic dissection.
Authors: SIliceto, N CNanda, PRizzon, M CHsuing, R GGoyal, AAmico, MSorino
Journal: Circulation (1987)

Color Doppler studies were performed in 16 adult patients with proven DeBakey type I and III aortic dissection. Simultaneous opacification of both aortic lumina with oppositely directed flow was noted by color Doppler in at least one aortic segment in 14 of 16 patients (12 type I, two type III). In two patients (one type I, one type III), flow was seen in one lumen only, with clot demonstrated in the other lumen in one of them. Of 12 patients in whom communication between two aortic dissection channels was shown by angiography/surgery, color Doppler correctly identified them in nine patients (four ascending aorta, two aortic arch, and three descending aorta), either by direct visualization of flow moving from one lumen into the other (six patients) or indirectly by analyzing differences in timing of opacification of the two lumina and flow direction (three patients). Also, color Doppler correctly diagnosed aortic regurgitation as severe (aortic regurgitation jet occupying more than 75% of left ventricular...