tbuckley/cabot-search huggingface dataset:
Cardiovascular responses to PGI2 (prostacyclin) in the dog.
Authors: T MFitzpatrick, IAlter, E JCorey, P WRamwell, J CRose, P AKot
Journal: Circulation Research (1978)

Arachidonic acid (AA) produces characteristic hemodynamic changes in the canine circulation. These responses are blocked by prostaglandin (PG) synthetase inhibitors, indicating that AA and its nonprostanoic metabolites are not vasoactive. The hemodynamic effects of the cyclic endoperoxides, thromboxanes, and PGD2, PG2, and PGF2a differ from those produced by AA. PGI2, a newly identified product of AA, is reported to relax arterial strips. However, its cardiac and systemic effects are unknown. In 12 open-chest, anesthetized dogs, PGI2 (0.25-5.0 microgram/kg) produced a dose-related decrease in systemic arterial pressure (BP) and myocardial contractile force (MCF). In five left ventricular bypass preparations, PGI2 produced only a slight decrease in MCF at all doses, whereas the BP decreases were parallel to those in the intact preparation. AA, PGD2, PGE2, and PGI2 were administered in random order by bolus intravenous injections in approximately equidepressor doses to intact dogs. BP fell with each agent (...
Increased embolic risk in patients with left ventricular thrombi.
Authors: J RStratton, A DResnick
Journal: Circulation (1987)

Although left ventricular thrombi are associated with an increased embolic risk in the first few weeks after acute myocardial infarction, the long-term risk remains undefined. To ascertain the incidence of strictly defined systemic emboli, we followed 85 patients with echocardiographically documented left ventricular thrombi. At the time of the entry echocardiogram, most patients (n = 57) had remote myocardial infarction, while 19 had recent (less than 1 month) infarction, and nine had idiopathic cardiomyopathy. Because of the difficulty in classifying events as embolic in patients with advanced atherosclerosis, a matched control group of 91 patients without thrombi was also studied. The thrombus and control groups were similar with regard to recent myocardial infarction, remote infarction, anterior infarction, ejection fraction, atrial fibrillation, echocardiographic referral for source of emboli, and warfarin therapy. During a mean follow-up of 22 months after echocardiography, embolic events occurred i...
Measuring the Real Clinical Impact of Randomized Clinical Trials in Oncology
Authors: Massimo Di Maio, Chiara Baratelli, Marco Tampellini
Journal: JAMA Oncology (2016)

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 Oncology HomeNew OnlineCurrent IssueFor Authors Podcast 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) 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 Oncology journal
The effect of high lung conductivity on electrocardiographic potentials. Results from human subjects undergoing bronchopulmonary lavage.
Authors: YRudy, RWood, RPlonsey, JLiebman
Journal: Circulation (1982)

The effect of increased lung conductivity on ECG potentials was studied in human subjects undergoing pulmonary lavage of a whole lung. In this procedure, the air in the lung is replaced by physiologic saline solution, which is a highly conductive fluid. The same situation was simulated theoretically with an eccentric spherical model of the heart and torso. Both the experimental results and theoretical simulations show a decrease in body-surface potentials as the lung conductivity increases. In particular, a large decrease was observed in the posterior vector and the scalar Z lead both experimentally and theoretically. The model simulation shows that the scalar Z lead is maximal at a conductivity value that is very close to the typical normal lung conductivity, so that low voltages are predicted for low lung conductivities as well.
Supernormal excitability as a mechanism of chaotic dynamics of activation in cardiac Purkinje fibers.
Authors: D RChialvo, D CMichaels, JJalife
Journal: Circulation Research (1990)

Supernormality, which can be defined as greater than normal excitability during or immediately after action potential repolarization, has been observed in a variety of cardiac preparations. However, as yet, no description of the dynamics of tissue response to repetitive stimulation in the presence of supernormal or relatively supernormal excitability has appeared. Isolated sheep cardiac Purkinje fibers (2-5 mm in length) were superfused with Tyrode's solution and stimulated with depolarizing current pulses through a suction pipette. Recovery of excitability, restitution of the action potential duration, and response patterns were measured in each fiber for a wide range of current amplitudes and stimulation frequencies. When the potassium chloride concentration of the Tyrode's solution was decreased from 7 to 4 mM, the excitability recovery function consistently changed from monophasic (normal) to triphasic (supernormal'). During repetitive stimulation at increasing rates, normal preparations responded ...
Are contraction and relaxation coupled in patients with and without congestive heart failure
Authors: E JEichhorn, J EWillard, LAlvarez, A SKim, D BGlamann, R CRisser, P AGrayburn
Journal: Circulation (1992)

BACKGROUNDAlthough changes in contractility are often accompanied by changes in relaxation, a mathematical model of ventricular coupling has not been described. A model we examined suggests a hyperbolic relation between measurements of contraction and relaxation. We thus tested the hypothesis that relatively load-independent measurements of contractility (end-systolic elastance [Ees]) and relaxation (the slope of the tau-to-end-systolic pressure relation [R]) were coupled.METHODS AND RESULTSTo establish the validity of the model, an assessment of Ees and R was made in 30 subjects who underwent sequential digital ventriculography and micromanometer pressure measurements during atrial pacing (93 +/- 10 min-1) before and after graded doses of nitroprusside. To establish if a cyclic AMP (cAMP)-mediated intervention alters coupling, seven of the 30 subjects were studied before and after 3 months of beta-blockade. To determine if a non-cAMP-mediated intervention alters coupling, 12 other patients were studied b...
A randomized controlled trial to investigate the effects of intra-dialytic cycling on left ventricular mass
Authors: Matthew P.M. Graham-Brown, Daniel S. March, Robin Young, Patrick J. Highton, Hannah M.L. Young, Darren R. Churchward, Maurice Dungey, David J. Stensel, Nicolette C. Bishop, Nigel J. Brunskill, Alice C. Smith, Gerry P. McCann, Alex McConnachie, James O. Burton
Journal: Kidney International (2021)
Calcific deposits developing in a bovine pericardial bioprosthetic valve 3 days after implantation.
Authors: TIshihara, V JFerrans, MJones, H SCabin, W CRoberts
Journal: Circulation (1981)

Calcific deposits, localized in a thin layer of thrombus covering the cuspal surfaces, were present 3 days after implantation in a valved pulmonic conduit that contained an Ionescu-Shiley bovine pericardial valve and was placed in a 29-year-old man with double outlet right ventricle, valvular and infundibular pulmonic stenosis, and ventricular septal defect. Factors that may have contributed to such a rapid calcification were the relatively young age of the patient, the development of acute renal insufficiency postoperatively, and the administration of large amounts of calcium chloride intravenously during blood transfusions and during episodes of cardiac arrest.
TCTAP C-027 Early Coronary Artery Bypass Graft (CABG) Failure in High SYNTAX Score: What’s Next?
Authors: Yew Fung Kwan, Tze Ming Chan, Jian-Chen Lim, Ramachandran Sathappan, Benjamin Tao Xiung Lim, Mohd Ruslan Mustapa, Gurpreet Pal Singh Jugindar Singh, Hameeth Shah Abdul Wahid, Hazleena Mohamed Hasnan, Nor Hanim Mohd Amin
Journal: Journal of the American College of Cardiology (2021)
Baroreceptor-heart rate reflex function before and after surgical reversal of two-kidney, one-clip hypertension in the rat.
Authors: M EEdmunds, G IRussell, P RBurton, J DSwales
Journal: Circulation Research (1990)

Baroreflex function was studied in conscious early phase (less than 6 weeks) two-kidney, one-clip hypertensive rats before and 24 hours after surgical reversal of hypertension by removal of the constricting renal artery clip or after pharmacological reduction of blood pressure by an infusion of hydralazine or captopril. A normotensive sham-clipped group was included. Another group of two-kidney, one-clip rats was studied 3 weeks after unclipping. Baroreflex sensitivity, as assessed by the steady-state method using a graded phenylephrine infusion, mean arterial pressure, and heart rate were measured preoperatively and at 24 hours postoperatively. Two-kidney, one-clip rats were significantly hypertensive preoperatively compared with control (mean arterial pressure, 183 +/- 4 vs. 106 +/- 2 mm Hg, p less than 0.001), heart rate was similar (420 +/- 9 vs. 401 +/- 9 beats/min, p greater than 0.05), and baroreflex sensitivity was significantly reduced (0.76 +/- 0.07 vs. 1.50 +/- 0.20 msec/mm Hg; p less than 0.00...
Breast Cancer: Treatment Differences and Survival
Authors: Andy Amster
Journal: JAMA (1994)

<h3>To the Editor.</h3> —We are concerned about the conclusion that Dr Lee-Feldstein and colleagues<sup>1</sup>reached about poor breast cancer survival in health maintenance organization (HMO) hospitals in Orange County, California. As the largest hospital-based HMO in Southern California, Kaiser Permanente for years has supported comparison of medical outcomes of all health care organizations. Therefore, we believe it is mandatory for us to provide an accurate reflection of our breast cancer statistics for stage at diagnosis and survival. The Kaiser Permanente Medical Care Program in Southern California has operated its own hospital-based cancer registries for more than 40 years. All but two of our 10 registries are certified by the American College of Surgeons. At all our registries, follow-up rates are more than 97%. The data on stage at diagnosis and survival rate are derived from this rich and unique data source. We analyzed 7819 patients with newly diagnosed breast
Industrial Poisons Encountered in the Manufacture of Explosives
Authors: Amy Hamilton
Journal: JAMA (1917)

Accidental explosions are so great a danger in the industry of making explosives that they overshadow the less spectacular but quite as real danger of industrial poisoning. The outbreak of the great war was followed in Great Britain by a rapid increase in the notifications of occupational poisoning from certain substances as a result of the enormous increase in the manufacture of ammunition of all kinds. What the experience of France and of the Central Powers has been we do not know, but there is no reason to suppose that they have escaped this natural consequence. Nor is there any reason to suppose that we have escaped it, since we too began to increase greatly our production of the ordinary explosives soon after the war broke out, and also to manufacture quite new ones. Consequently, it seemed desirable to learn whether here too this industry has been attended with a
High Confidence Optical Diagnosis Of Small Polyps at Colonoscopy Versus Histopathology: Moving Towards a New Gold Standard?
Authors: A Ahmad, A Wilson, M Moorghen, A Dhillon, S Thomas-Gibson, N Suzuki, A Humphries, A Haycock, K Monahan, M Vance, B Saunders
Journal: Endoscopy (2021)

Aims Histopathology is regarded as the gold standard for diagnosis of small colonic polyps. However, there is growing interest in optical diagnosis and implementation of a ‘resect and discard’ strategy. Our aim is to evaluate accuracy of histopathology reporting where a high confidence diminutive polyp optical diagnosis was made and to assess the impact of performing additional tissue section re-cuts, where there is a discrepancy.
An in situ-forming polyzwitterion hydrogel: Towards vitreous substitute application
Authors: Binbin He, Jianhai Yang, Yang Liu, Xianhua Xie, Huijie Hao, Xiaoli Xing, Wenguang Liu
Journal: Bioactive Materials (2021)

Development of a biostable and biosafe vitreous substitute is highly desirable, but remains a grand challenge. Herein, we propose a novel strategy for constructing a readily administered vitreous substitute based on a thiol-acrylate clickable polyzwitterion macromonomer. A biocompatible multivinyl polycarboxybetaine (PCB-OAA) macromonomer is designed and synthesized, and mixed with dithiothreitol (DTT) via a Michael addition reaction to form a hydrogel in vitreous cavity. This resultant PCB-OAA hydrogel exhibits controllable gelation time, super anti-fouling ability against proteins and cells, excellent biocompatibility, and approximate key parameters to human vitreous body including equilibrium water content, density, optical properties, modulus. Remarkably, outperforming clinically used silicone oil in biocompatibility, this rapidly formed hydrogel in the vitreous cavity of rabbit eyes remains stable in vitreous cavity, showing an appealing ability to prevent significantly inflammatory response, fibrosis and complications such as raised intraocular pressure (IOP), and cataract formation. This zwitterionic polymer hydrogel holds great potential as a vitreous substitute.
Electrophysiology and ultrastructure of canine subendocardial Purkinje cells isolated from control and 24-hour infarcted hearts.
Authors: P ABoyden, AAlbala, K PDresdner
Journal: Circulation Research (1989)

Ventricular arrhythmias that accompany myocardial infarction in dogs may be secondary to the altered electrophysiological properties of the subendocardial Purkinje fibers that survive 24 hours after the coronary occlusion. To better understand the ionic mechanisms that underlie the altered electrical activity of these fibers, we have dispersed, using an enzymatic technique, Purkinje cells from the subendocardium of the infarcted ventricle (IZPCs) and compared their electrical and structural properties to Purkinje cells dispersed from fiber strands (SPCs) and from the subendocardium of the noninfarcted ventricle (NZPCs). Ultrastructural analysis of these cells shows that IZPCs contain an increased number of lipid droplets when compared with the SPCs and NZPCs. In addition, transmembrane action potentials of IZPCs have reduced resting potentials, action potential amplitudes, and upstroke velocity and are increased in duration when compared with either SPCs or NZPCs. Input resistance of IZPCs is increased ov...
Dipyridamole decreases glomerular filtration in the sodium-depleted dog. Evidence for mediation by intrarenal adenosine.
Authors: L JArend, C IThompson, W SSpielman
Journal: Circulation Research (1985)

To determine the renal effects of inhibiting the uptake and subsequent metabolism of endogenous adenosine, dipyridamole, a nucleoside transport inhibitor, was infused intrarenally into anesthetized dogs. Dipyridamole (24 micrograms/kg per min) inhibited the cellular extraction of [14C]adenosine (72 +/- 3% vs. 9 +/- 3%) and elevated the excretion of endogenous adenosine (0.60 +/- 0.08 to 1.70 +/- 0.21 nmol/min, P less than 0.05). The action of exogenous adenosine to decrease glomerular filtration rate is known to be enhanced by sodium depletion, and is minimal or absent in sodium-loaded animals. To ascertain whether dietary sodium intake alters the renal effects of elevated endogenous adenosine, dipyridamole was infused into sodium-depleted and sodium-loaded dogs. In the sodium-depleted dogs (n = 9), dipyridamole infusion decreased the glomerular filtration rate by 59 +/- 7% (20 +/- 1 to 8 +/- 2 ml/min, P less than 0.05) which returned to control levels within 30 minutes after stopping infusion of dipyrida...
Circumferential Endoscopic Submucosal Dissection for Early Squamous Cell Carcinoma Using Double-Tunnel and Clip-Thread Technique
Authors: S Bassioukas, C Katzakis, D Gkaraganis, L Chantzinicolaou
Journal: Endoscopy (2021)

A 51 years old female diagnosed with a high-grade squamous cell dysplasia at the cervical esophagus was referred to our department for endoscopic resection.
Action potentials in chick atria. Ontogenetic changes in the dependence of tetrodotoxin-resistant action potentials on calcium, strontium, barium.
Authors: A JPappano
Journal: Circulation Research (1976)

Action potentials were recorded from chick embryo atrial muscle cells bathed in Tyrode's solution. Tetrodotoxin (TTX), 3.1 muM, was added to block the early, transient, Na+-dependent conductance system. Rectangular stimuli were used to evoke action potentials the peak amplitude (Ep) of which depend on the external concentration of divalent cations, [Me2+]0. The relationship between Ep and [Me2+]0 shifted to the right with increasing age. For example, the slope of Ep was 33 +/- 2,22 +/- 1 and 11 +/- 3 mV per 10-fold change in [Ca2+]0 on the 9th, 12th, and 18th incubation days, respectively. In solutions with reduced [Ca2+]0, Ep increased when Ba2+ or Sr2+ was added to the bath. The potency of Me2+ in generating action potentials was Ba2+ greater than Sr2+ greater than Ca2+ and this sequence did not change during development. Action potential amplitude, which was reduced in 18-day preparations, was increased by isoproterenol (increased Ca2+ conductance, gCa2+) and by tetraethylammonium (TEA) ion (decreased ...
Pseudopolyps in Inflammatory Bowel Disease: Complications and Developing-Associated Factors
Authors: M Ghribi, S Laabidi, B Bouchabou, W Bougassas, H Ben Nejma, R Ennaifer
Journal: Endoscopy (2021)

Aims Pseudopolyp (PP)are considered as indicators of previous episodes of severe inflammation. The reasons that a specific group of inflammatory bowel disease (IBD)patients develop PP remain unclear. Our study aimed at describing the characteristics of patients with PP and at investigating the associated factors of their occurrence as well as their possible complications.
Potential arrhythmogenic electrophysiological derangements in canine Purkinje fibers induced by lysophosphoglycerides.
Authors: P BCorr, M ECain, F XWitkowski, D APrice, B ESobel
Journal: Circulation Research (1979)

We have recently detected accumulation of lysophosphoglycerides, catabolites of phospholipids, in ischemic myocardium early after coronary occlusion. In the present study we delineated effects of selected concentrations of albumin-bound lysophosphatidyl choline (LPC) comparable to those accompanying ischemia in vivo on action potentials of isolated canine Purkinje fibers. Lysophosphoglycerides induced concentration-dependent (0.75-3.0 mM) decreases in resting membrane potential, overshoot of phase 0, maximal velocity of upstroke (Vmax) of phase 0, and action potential duration. The highest concentrations (2.0-3.0 mM) induced fractionation of the action potential into several components, unresponsiveness to external stimulation, and enhanced automaticity at normal and reduced membrane potentials. LPC induced a rightward shift in the membrane response curve, a 40-fold prolongation of conduction time, and an increase in the ratio of effective refractory period to action potential duration such that the effec...
Lipoprotein predictors of the severity of coronary artery disease in men and women.
Authors: M FReardon, P JNestel, I HCraig, R WHarper
Journal: Circulation (1985)

In this study we examined the relationships between levels of several components of plasma lipoproteins and severity of coronary artery disease in 65 men and 42 women who underwent coronary arteriography for suspected coronary disease. Severity of coronary atherosclerosis was scored as the extent of disease seen at arteriography. Univariate analyses of the relationships between the plasma lipoprotein parameters and score for severity of atherosclerosis revealed a marked difference between men and women. In men, the score for severity of atherosclerosis was strongly related to the low-density lipoprotein (LDL) cholesterol and apolipoprotein B concentrations, whereas in women it was related to the triglyceride concentrations in plasma intermediate-density lipoprotein (IDL) and LDL and to the cholesterol and apolipoprotein B concentrations in IDL. The significance of these correlations was not negated by possible confounding factors such as alcohol intake, diabetes, and treatment with thiazides and beta-adre...
Inhibition of platelet adhesion to surfaces of extracorporeal circuits by disintegrins. RGD-containing peptides from viper venoms.
Authors: JMusial, SNiewiarowski, BRucinski, G JStewart, J JCook, J AWilliams, L HEdmunds
Journal: Circulation (1990)

Previous studies indicate that exposure of fibrinogen receptors associated with glycoprotein IIb/IIIa complex contributes to platelet loss during cardiopulmonary bypass. Recently, we isolated a number of RGD (Arg-Gly-Asp)-containing, low molecular weight, cysteine-rich peptides from viper venoms. These peptides, which we propose to call disintegrins, block platelet-fibrinogen interaction and platelet aggregation. We compared the effect of RGDS (Arg-Gly-Asp-Ser) and four disintegrins (echistatin, flavoridin, albolabrin, and bitistatin) on platelet behavior in a membrane oxygenator. During simulated extracorporeal circulation for 2 hours, platelet count decreased to about 30% of initial values. Addition of echistatin (60-200 nM), albolabrin (60-200 nM), bitistatin (60 nM), and flavoridin (45 nM) significantly inhibited platelet loss in the circuit. RGDS (33 microM) did not show any significant inhibitory effect. ADP-induced platelet aggregation was inhibited in samples of platelet-rich plasma taken from t...
Patient Preference for Colon Capsule Endoscopy or Colonoscopy in Population-Based Colorectal Cancer Screening: Interim Analysis of First 39,076 Invitations for Fecal Immunochemical test in Careforcolon2015
Authors: U Deding, T Bjørsum-Meyer, L Kaalby, M Kobaek-Larsen, MK Thygesen, G Baatrup
Journal: Endoscopy (2021)

Aims To compare participation rates for fecal immunochemical test (FIT) prior to offering colon capsule endoscopy (CCE) or colonoscopy with controls offered only colonoscopy as follow-up to positive FIT, and to analyze the choice of screening method in the intervention group within the large randomized clinical trial CareForColon2015[ 1 ].
Pulmonary function, activated T cells, peripheral blood eosinophilia, and serum activity for eosinophil survival in vitro: A longitudinal study in bronchial asthma
Authors: Johann-Christian Virchow, Albert Oehling, Lisbeth Boer, Trevor T. Hansel, Peter Werner, Heinrich Matthys, Kurt Blaser, Christoph Walker
Journal: Journal of Allergy and Clinical Immunology (1994)