tbuckley/cabot-search huggingface dataset:
Characterization of muscarinic acetylcholine receptors expressed by an atrial cell line derived from a transgenic mouse tumor.
Authors: M EMorton, CBrumwell, C LGartside, S DHauschka, N MNathanson
Journal: Circulation Research (1994)

The properties of muscarinic acetylcholine receptors in the cell line MCM1, derived from an SV40 T-antigen-induced atrial tumor in a transgenic mouse, were determined. Binding studies using the nonselective muscarinic antagonist [3H]quinuclidinyl benzilate, the M1-selective antagonist pirenzepine, and the M2-selective antagonist AFDX-116 indicate that the receptors have the pharmacological properties of the cardiac (M2) receptor subtype. The receptors could be immunoprecipitated with a monoclonal antibody specific for the cardiac receptor, thus confirming the identity of the receptors expressed in these cells. The types of G proteins expressed in the cells were determined by Northern blot analyses: mRNA encoding the alpha subunits of Gs, G(o), and Gi-2, but not Gi-1 or Gi-3, were detected, consistent with previous observations of neonatal mammalian atria. The muscarinic receptors were functionally active, as demonstrated by the ability of the agonist to stimulate phosphoinositide turnover and to inhibit a...
Baroreflex control of renal sympathetic nerve activity is preserved in heart failure despite reduced arterial baroreceptor sensitivity.
Authors: M EDibner-Dunlap, M DThames
Journal: Circulation Research (1989)

The purpose of this study was to determine if arterial baroreflex control of sympathetic nerve traffic is impaired in heart failure. We recorded renal nerve activity during changes in arterial pressure while simultaneously recording from aortic baroreceptor afferent fibers in 10 dogs with heart failure induced by rapid ventricular pacing and in 10 sham animals. Sensitivity of the aortic baroreceptors (percent change in nerve activity per millimeters mercury change in mean arterial pressure) was reduced in the heart failure group (heart failure, 2.3 +/- 0.3; sham, 3.6 +/- 0.4, p = 0.02). Despite the reduced sensitivity of aortic baroreceptors in heart failure, there was no difference in the baroreflex gain of renal nerve activity (heart failure, -5.5 +/- 1.4; sham, -5.8 +/- 1.3, p = NS). These values tended to decrease in both groups after vagotomy. The relation between baroreceptor input and renal sympathetic output, or central baroreflex gain (percent change in renal nerve activity divided by percent cha...
Hepatology: A Textbook of Liver Disease
Authors: J O'Grady
Journal: Gut (1997)

Book reviews, Notes it may have more limited appeal for the more experienced gastroenterologist.The second half of volume two is also unusual, being devoted to diagnostic and therapeutic procedures including endoscopy, imaging, mucosal biopsy, microbiology, and motility studies.Once again of particular appeal to the younger postgraduate.Sandwiched between these sections on basic mechanisms, symptoms, and diagnostic and therapeutic approaches are some 60 chapters devoted to diseases as they are mani- fest sequentially along the gastrointestinal tract.These contributions are all a pleasure to read and are uniformly well presented and illustrated.The presentations of a consistently high quality and the apparently seamless links from one chapter to the next provide remark- able continuity -a major editorial achievement.
Circus movement in the canine atrium around the tricuspid ring during experimental atrial flutter and during reentry in vitro.
Authors: L HFrame, R LPage, P ABoyden, J JFenoglio, B FHoffman
Journal: Circulation (1987)

A Y-shaped lesion in the right atrium allows induction of atrial flutter in dogs. We recorded the activation sequence during this tachycardia from 96 endocardial bipolar electrodes using intracavitary electrode arrays during 12 separate episodes in three isolated perfused hearts. In each case a reentrant impulse circulated around the tricuspid valve orifice in either a clockwise or counter-clockwise direction. Cutting the pathway terminated the rhythm and prevented its reinduction. There was no discrete segment of markedly slow conduction in the reentrant circuit. The tachycardia cycle length was decreased by methacholine and increased by lidocaine. Reentry was also induced in atrial tissue around the tricuspid orifice when this structure was isolated and superfused in vitro. Tachycardia cycle lengths varied from 205 to 399 msec, depending on the circumference of the ring and temperature. Induction of tachycardia by premature stimulation depended on differences in the duration of the effective refractory ...
Acute Upper Gastrointestinal Bleeding: Less Severe Bleeding In More Frail and Older Patients. Comparison Between Two Periods Fifteen Years Apart
Authors: G Diamantopoulou, E Tsounis, K Papantoniou, M Kalafateli, C Konstantakis, G Theocharis, C Triantos, K Thomopoulos
Journal: Endoscopy (2021)

Aims Acute upper gastrointestinal bleeding (AUGIB) remains a common medical emergency with considerable morbidity and mortality. The aim of this study was to compare characteristics of patients presented with AUGIB today with those of patients15 years ago.
PET/CT Imaging for Langerhans Cell Histiocytosis Involving Only Posterior Elements of the Cervical Vertebra
Authors: Wenjie Zhang, Hangyu Xie, Minggang Su
Journal: Clinical Nuclear Medicine (2021)

Abstract Langerhans cell histiocytosis only involving the posterior elements of the spine is rare. We report the case of a 7-year-old boy who has pain and restricted motion of his neck. 18 F-FDG PET/CT revealed an osteolytic lesion in the posterior elements of the fourth cervical vertebra. The lesion has high 18 F-FDG uptake with an SUVmax of 8.01. An operation was performed, and the final pathological finding revealed Langerhans cell histiocytosis.
Demonstrating Noninferiority of Accelerated Radiotherapy With Panitumumab vs Standard Radiotherapy With Cisplatin in Locoregionally Advanced Squamous Cell Head and Neck Carcinoma
Authors: David Cheng, Kyongsun Pak, Lee-Jen Wei
Journal: JAMA Oncology (2017)

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
Effect of digoxin on atioventricular conduction. Studies in patients with and without cardiac autonomic innervation.
Authors: D JGoodman, R MRossen, D SCannom, A KRider, D CHarrison
Journal: Circulation (1975)

The effect of digoxin on atrioventricular (a-v) conduction was compared in five patients with an intact cardiac autonomic nervous system (Group I) and seven patients who had undergone cardiac transplantation (Group II), in whom we have previously shown the transplanted heart to be completely denervated. Small decreases in the atrial effective refractory period (ERP) (from 262 plus or minus 12 to 254 plus or minus 11 msec) and atrial functional refractory period (FRP) (from 304 plus or minus 12 msec) were observed in Group I patients after digoxin, but these changes were not significant. However, significant increases in the A-V nodal ERP (from 315 plus or minus 18 msec to 351 plus or minus 17 msec, P less than 0.05), and A-V nodal FRP (from 426 plus or minus 42 to 460 plus or minus 46 msec, P less than 0.01) were produced by digoxin and were unrelated to changes in cycle length. In Group II patients with denervated hearts, changes in atrial ERP (from 246 plus or minus 4 to 243 plus or minus 6 during spont...
Advanced-Stage Hodgkin Lymphoma in the East of England Cancer Network: A 10-Year Comparative Analysis of Outcomes for Patients Treated with ABVD or Escalated BEACOPP in the Non-Trial Setting Compared with Age-Matched Patients Treated in the Multinational RATHL Trial
Authors: James Russell, Angela Collins, Alexis Fowler, Mamatha Karanth, Isabel Lentell, Chandan Saha, Suzanne Docherty, Joseph Padayatty, Kyaw Maw, Lisa Cooke, Andrew Hodson, Nimish Shah, Shalal Sadullah, Nicholas Grigoropoulos, Wendi Qian, Amy A Kirkwood, Benjamin J Uttenthal, Peter Johnson, George A Follows
Journal: Blood (2017)
The Rhesus Macaque Serves As a Model for Human Lateral Branch Nephrogenesis
Authors: Meredith P. Schuh, Lyan Alkhudairy, Andrew Potter, S. Steven Potter, Kashish Chetal, Kairavee Thakkar, Nathan Salomonis, Raphael Kopan
Journal: Journal of the American Society of Nephrology (2021)

Most nephrons are added in late gestation. Truncated extrauterine nephrogenesis in premature infants results in fewer nephrons and significantly increased risk for CKD in adulthood. To overcome the ethical and technical difficulties associated with studies of late-gestation human fetal kidney development, third-trimester rhesus macaques served as a model to understand lateral branch nephrogenesis (LBN) at the molecular level.
Impact Of Chronic Statin-Use On The Risk Of Post-Ercp Pancreatitis With Or Without Rectal Non-Steroidal Anti-Inflammatory Drugs (NSAIDS)
Authors: S Bota, M Razpotnik, D Edlinger, G Essler, J Weber-Eibel, M Peck-Radosavljevic
Journal: Endoscopy (2021)

Aims To assess impact of preexisting statin-use on the pancreatitis risk after endoscopic retrograde cholangio- pancreatography (ERCP) with or without rectal NSAIDs.
Effects of K+ and K+-induced polarization on (dV/dt)max, threshold potential, and membrane input resistance in guinea pig and cat ventricular myocardium.
Authors: HKishida, BSurawicz, L TFu
Journal: Circulation Research (1979)

We studied the non-membrane potential-dependent effect of K+ on (dV/dt)max and threshold potential in guinea pig and cat ventricular myocardium. Membrane potential (MP) was changed uniformly in segments (length less than or equal to 1.0 mm) of papillary muscles by applying extracellular polarizing current pulses across a single sucrose gap. Control [K+]o was 5.4 mM and test [K+]o values were 2.0, 10.0, 11.5, 13.0, 16.2, 20, 22, and 24.0 mM. Each muscle was studied under four conditions: (1) control [K+]o and unaltered (control level) resting MP (Em); (2) one of the test [K+]o values and the unaltered (test level) Em; (3) the same test [K+]o and Em held at the control level; (4) control [K+]o and Em held at the test level. At all [K+]o greater than or equal to 11.5 mM, (dV/dt)max showed a decrease significantly (P less than 0.01) greater than the corresponding MP-dependent decrease in both guinea pig and cat myocardium. This non-MP-dependent decrease averaged 7.5% at 11.5 mM, 26.5% at 13.0 mM, 37.2% at 16....
Putative mechanism of hypotensive action of platelet-activating factor in dogs.
Authors: SYamanaka, KMiura, TYukimura, MOkumura, KYamamoto
Journal: Circulation Research (1992)

We examined the mechanism(s) of hypotensive action of platelet-activating factor (PAF) in anesthetized dogs. PAF (0.5 micrograms/kg i.v.) caused a biphasic hypotension; the first phase was transient and was accompanied by a decrease in systemic vascular resistance and an increase in cardiac output. Aspirin-DL-lysine, a cyclooxygenase inhibitor, had no effect on this phase. The second phase was characterized by a sustained hypotension caused by a reduction in cardiac output and was accompanied by an increase in systemic and pulmonary vascular resistance. The plasma concentrations of 6-ketoprostaglandin F1 alpha and thromboxane B2 also increased. These changes were markedly attenuated by aspirin. Both atrial pressures decreased during the second phase, thereby indicating that the PAF-induced reduction in cardiac output was related to a hindrance in venous return. The hematocrit increased, and aspirin did not affect this change. The extravasation of plasma probably plays a minor role, whereas venodilation wo...
Computer-Aided Characterisation Of Colorectal Polyps Using Artificial Intelligence
Authors: R Kader, P Brandao, O Ahmad, M Hussein, S Islam, T De Carvalho, J Puyal, V Sehgal, P Mountney, R Vega, E Seward, D Stoyanov, L Lovat
Journal: Endoscopy (2021)

Aims Optical diagnosis is the in-vivo prediction of colorectal polyp histopathology but inter-observer variability amongst endoscopists has limited its application in clinical practice. Artificial Intelligence, using deep learning, may lead to a new generation of clinical support tools capable of characterising polyps. Our aim was to develop a convolutional neural network (CNN) to characterise colorectal polyps as adenomatous or non-adenomatous.
The effects of milrinone on conduction, reflection, and automaticity in canine Purkinje fibers.
Authors: J MDavidenko, CAntzelevitch
Journal: Circulation (1984)

Milrinone is a newly developed analogue of amrinone possessing potent positive inotropic action. Electrophysiologic actions of the drug have not been reported. In this study microelectrode techniques were used to assess the electrophysiologic effects of milrinone in canine false tendons homogeneously superfused with either normal or high-K Tyrode's solution and in Purkinje fibers mounted in a three-compartment chamber in which the central segment was depressed with an  solution. Milrinone (0.2 to 20 micrograms/ml) caused no major changes in the action potential characteristics, refractoriness, or conduction velocity in fibers exposed to normal Tyrode's solution, but markedly improved conduction and abbreviated or eliminated postrepolarization refractoriness in the ischemic gap preparations. The drug also exerted important effects on reflected reentry generated in these preparations. Depending on the initial level of block, milrinone (1) suppressed the arrhythmia, (2) shifted its frequency depend...
Abstract 16533: Heterogeneity of Fibrosis in Patients Undergoing Combined Heart-Liver Transplant
Authors: Joshua Rushakoff, Evan P Kransdorf, Maha Guindi, Jignesh K Patel, Jon A Kobashigawa
Journal: Circulation (2020)

Introduction: Combined heart-liver transplant (CHLT) is indicated for patients with end-stage heart failure and concomitant irreversible liver injury. Given that liver dysfunction from congestive hepatopathy is common in patients with end-stage heart failure, it can be difficult to determine reversible from irreversible liver injury. Transjugular liver biopsy (TJLB) is frequently used to evaluate the severity of parenchymal injury, but is limited by heterogeneity of fibrosis across biopsy specimens. We sought to compare the fibrosis evaluation of the TJLB specimens as compared to the pathology of the liver explant at the time of CHLT. Methods: All CHLT cases at CSMC between 2007 and 2017 were included. Demographic and liver ultrasound (US) or abdominal computed tomography (CT) imaging was retrieved by chart review. TJLB was performed prior to transplant to determine the severity of liver fibrosis and was compared to the pathology of the liver explant. A biopsy was considered to show heterogenous fibrosis if there was at least a 2 stage difference between the predominant and secondary patterns. Results: Thirteen CHLTs were performed at our center during the study period. The median follow-up was 59 months (IQR 48-67). Mean age at transplant was 53 years (SD +/- 14.9) and 77% of patients were male. Indications for CHLT included cardiac cirrhosis (7), amyloidosis (2), HCV cirrhosis (2), and congenital heart disease (2). By imaging, 3/7 patients (43%) had US and CT evidence, 2/7 (29%) had US or CT evidence, and 2/7 (29%) had no evidence of liver nodularity US or CT. All patients diagnosed with cardiac cirrhosis had both TJLB and explant pathology for review. All TJLBs were graded as stage 4 fibrosis. Fibrosis on analysis of the liver explant was variable: stage 4 (2), stage 3-4 (3), stage 2-4 (1), and stage 1-4 (1). Thus, 2/7 patients (29%) showed heterogeneity of fibrosis in their explant as compared to their TJLB. Conclusions: We found heterogeneity of fibrosis in liver explants of patients that had stage 4 fibrosis (cirrhosis) by TJLB and underwent CHLT. Further work is needed to identify which heart transplant candidates will most benefit from CHLT.
In vivo magnetic resonance spectroscopy measurement of deoxymyoglobin during exercise in patients with heart failure. Demonstration of abnormal muscle metabolism despite adequate oxygenation.
Authors: D MMancini, J RWilson, LBolinger, HLi, KKendrick, BChance, J SLeigh
Journal: Circulation (1994)

BACKGROUNDSkeletal muscle metabolic abnormalities have been described in patients with heart failure that are independent of total limb perfusion, histochemical changes, and muscle mass. However, these skeletal muscle metabolic abnormalities may result from tissue hypoxia caused by maldistribution of flow. Myoglobin is an O2 binding protein that can indirectly assess tissue hypoxia.METHODS AND RESULTSIn vivo measurement of deoxymyoglobin was performed by use of proton (1H) magnetic resonance spectroscopy in 16 heart failure (HF) (left ventricular ejection fraction = 20 +/- 6%; VO2 = 14.5 +/- 5.1 mL/kg per minute) and 7 healthy (Nl) subjects. Simultaneous phosphorus (31P) magnetic resonance spectroscopy and near-infrared spectroscopy also were obtained to examine muscle metabolism and oxygenation. Supine calf plantarflexion was performed every 4 seconds. Incremental steady-state work was performed. A second exercise protocol studied rapid incremental (RAMP) exercise with plantarflexion every 2 seconds. Art...
Increased lung vasoreactivity in children from Leadville, Colorado, after recovery from high-altitude pulmonary edema.
Authors: J WFasules, J WWiggins, R RWolfe
Journal: Circulation (1985)

Cardiac catheterization was performed on seven children after recovery from high-altitude pulmonary edema. All were life-long residents at elevations above 10,000 feet. Three of the seven had developed pulmonary edema without antecedent travel to low altitude but had an upper respiratory infection. Response of pulmonary arterial pressure to 16% inspired oxygen in all seven was compared with that in six well children who resided at a similar altitude and had no history of high-altitude pulmonary edema. With hypoxia the susceptible patients had a greater mean pulmonary arterial pressure (56.3 +/- 23.8) than the nonsusceptible children (18.8 +/- 3.9, p less than .05). Comparison with historical hemodynamic responses in children at high altitudes showed a similar greater mean pulmonary arterial pressure in the susceptible children. Thus, in children from high altitudes, increased pulmonary vasoreactivity to hypoxia may play a role in the pathogenesis of high-altitude pulmonary edema. The development of pulmon...
Trans-fatty acids intake and risk of myocardial infarction.
Authors: AAscherio, C HHennekens, J EBuring, CMaster, M JStampfer, W CWillett
Journal: Circulation (1994)

BACKGROUNDConcern that trans-fatty acids formed in the partial hydrogenation of vegetable oils may increase the risk of coronary disease has existed for several decades, but direct evidence on this relation in humans is limited.METHODS AND RESULTSWith a case-control design, we studied the association between intake of trans-fatty acids and a first acute myocardial infarction among 239 patients admitted to one of six hospitals in the Boston area and 282 population control subjects. Intake of trans-fatty acids was estimated using a previously validated food frequency questionnaire. After adjustment for age, sex, and energy intake, intake of trans-fatty acids was directly related to risk of myocardial infarction (relative risk for highest compared with lowest quintile, 2.44; 95% confidence interval, 1.42, 4.19; for trend P < .0001). This relation remained highly significant after adjustment for established coronary risk factors, multivitamin use, and intake of saturated fat, monounsaturated fat, linoleic aci...
Effects of lower-body negative pressure on sympathetic nerve responses to static exercise in humans. Microneurographic evidence against cardiac baroreflex modulation of the exercise pressor reflex.
Authors: UScherrer, S FVissing, R GVictor
Journal: Circulation (1988)

Although previous studies in both animals and humans have suggested that cardiac baroreceptors modulate reflex sympathetic vasoconstriction during exercise, more recent studies in conscious animals have not supported this view. To further test this concept in humans, we measured sympathetic nerve discharge with intraneural microelectrodes while we used static handgrip to activate the exercise pressor reflex and nonhypotensive lower-body negative pressure (LBNP) to selectively unload the cardiac baroreflex. In nine healthy subjects, we measured blood pressure, heart rate, central venous pressure, and muscle sympathetic nerve activity (MSNA) from the peroneal nerve (resting leg) during 2 minutes of static handgrip at 20% and 30% of maximal voluntary contraction (MVC) alone and in combination with LBNP at -5 mm Hg. Handgrip alone (exercise reflex) at 20% and 30% MVC caused graded increases in MSNA. LBNP alone (cardiac reflex) did not alter blood pressure or heart rate but decreased central venous pressure by...
Difficult Biliary Cannulation: What To Do?
Authors: SEl Aoula, M Borahma, N Lagdali, I Benelbarhdadi, FZ Ajana
Journal: Endoscopy (2021)

Aims Biliary cannulation (BC) failure can occur in 5-10 % of cases, but before concluding to cannulation failure, some techniques can be attempted (double guidewire technique (DGT), the precut, and the Trans pancreatic sphincterotomy…). BC rate > 85 % is the goal of any endoscopist involved in Endoscopic Retrograde Cholangiopancreatography (ERCP).
Is fibrillation chaos
Authors: D TKaplan, R JCohen
Journal: Circulation Research (1990)

Ventricular fibrillation is examined to determine whether it is an instance of deterministic chaos. Surface ECGs from dogs in fibrillation were used to generate a state space representation of fibrillation. Our analysis failed to identify a low-dimensional attractor that could be associated with fibrillation. The results suggest that fibrillation is similar to a nonchaotic random signal. We note, however, that such random-looking but nonchaotic behavior can also be generated by a nonlinear deterministic system.
Sensitization of dog and guinea pig heart myofilaments to Ca2+ activation and the inotropic effect of pimobendan: comparison with milrinone.
Authors: KFujino, NSperelakis, R JSolaro
Journal: Circulation Research (1988)

We compared the effects of the newer inotropic drugs, pimobendan (UD-CG 115 BS) and milrinone (Win 47203), on the electrical, mechanical and biochemical activity of intact and detergent-skinned preparations of cardiac muscle. Both of these agents increased contractile force of guinea pig papillary muscle preparations bathed under physiological conditions or depolarized with 25 mM K+o. The positive inotropic action was associated with potentiation of the Ca2+-dependent slow action potentials (APS). Contractile force developed in the presence of 25 mM [K]o and 1 microM isoproterenol was increased further by addition of 50 microM pimobendan with no effect on the slow action potential. Milrinone (50 microM) did not produce a further increase in the force or potentiate the slow APs. Pimobendan, in a dose-dependent manner, increased active tension developed by chemically-skinned dog heart muscle fibers at submaximally activating concentrations of Ca2+, whereas milrinone did not. At pCa 6.25, the half-maximal co...