tbuckley/cabot-search huggingface dataset:
Kinetics of 13N-ammonia uptake in myocardial single cells indicating potential limitations in its applicability as a marker of myocardial blood flow.
Authors: BRauch, FHelus, MGrunze, EBraunwell, GMall, WHasselbach, WKübler
Journal: Circulation (1985)

To study kinetics and principles of cellular uptake of 13N-ammonia, a marker of coronary perfusion in myocardial scintigraphy, heart muscle cells of adult rats were isolated by perfusion with collagenase and hyaluronidase. Net uptake of 13N, measured by flow dialysis, reached equilibrium within 20 sec in the presence of sodium bicarbonate and carbon dioxide (pH 7.4, 37 degrees C). Total extraction, 80 sec after the reaction start, was 786 +/- 159 mumol/ml cell volume. Cells destroyed by calcium overload were unable to extract 13N-ammonia. Omission of bicarbonate and carbon dioxide reduced total extraction to 36% of control. 13N-Ammonia uptake could also be reduced by 50 muM 4,4' diisothiocyanostilbene 2,2' disulfonic acid, by 100 micrograms/ml 1-methionine sulfoximine, and by preincubation with 5 muM free oleic acid. These results indicate that in addition to metabolic trapping by glutamine synthetase, the extraction of 13N-ammonia by myocardial cells is influenced by cell membrane integrity, intracellula...
Afferent neural pathway in the regulation of cardiopulmonary responses to tissue hypermetabolism.
Authors: C SLiang, W BHood
Journal: Circulation Research (1976)

We studied the role of neural transmission from hypermetabolic peripheral tissues in the regulation of cardiac output and pulmonary ventilation in chloralose-anesthetized dogs. Cross-circulation techniques with femoral-femoral or femoral-aortic anastomoses were used to produce a vascularly isolated, but normally innervated, hindlimb or lower half-body, 2,4-Dinitrophenol (DNP) was infused into the arterial side of the perfusion circuit to triple oxygen consumption and to increase lactate production by the cross-perfused area. After infusion of DNP, cardiac output and mean systemic arterial blood pressure increased, but neither heart rate nor pulmonary artery wedge pressure changed significantly. Pulmonary minute ventilation and arterial pH also increased, while arterial PCO2 fell. These changes were abolished when the nerve connections between the perfused limb and its parent body were severed. Normal saline, when administered in a similar manner, did not increase either ventilation or cardiac output, and ...
Effectiveness and Safety of 1L PEG-ASC Preparation for Colonoscopy in Patients With Inflammatory Bowel Diseases
Authors: M Maida, GC Morreale, S Sferrazza, E Sinagra, G Scalisi, D Schillaci, A Vitello, G Vettori, F Rossi, D Catarella, CE Di Bartolo, S Pallio, M Manganaro, S Camilleri, Macaluso FS
Journal: Endoscopy (2021)

Aims The effectiveness of bowel cleansing is a key element for a quality colonoscopy, especially in patients with inflammatory bowel diseases (IBD), both for assessment of mucosal healing and for detection of pre-neoplastic lesions during surveillance.
Course of bereavement over 8-10 years in first degree relatives and spouses of people who committed suicide: longitudinal community based cohort study
Journal: BMJ (2013)

Course of bereavement over 8-10 years in first degree relatives and spouses of people who committed suicide: longitudinal community based cohort studyThe authors of this Research paper have alerted us to some errors in table 4 (BMJ 2013;347:f5519, doi:10.1136/bmj.f5519)
Debunking Myths About the Purpose and Intentions of Fundamentals of Laparoscopic Surgery Testing—Reply
Authors: Emily D. Dubina, Xuan-Binh D. Pham, Christian de Virgilio
Journal: JAMA Surgery (2019)

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 Surgery 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 Surgery journal
No Impact of Pharmacokinetics Profiles on the Clinical and Biological Response to Hydroxyurea in Children with Sickle Cell Disease
Authors: Maria Karimi, Anar Rodriguez Cheang, Laurence Dedeken, Phu-Quoc Lê, Laurence Rozen, Malou Ngalula Mujinga, Bernard Wenderickx, Alina Ferster
Journal: Blood (2017)
Influence of compression rate on initial success of resuscitation and 24 hour survival after prolonged manual cardiopulmonary resuscitation in dogs.
Authors: M PFeneley, G WMaier, K BKern, J WGaynor, S AGall, A BSanders, KRaessler, L HMuhlbaier, J SRankin, G AEwy
Journal: Circulation (1988)

The influence of chest compression rate on initial resuscitation success and 24 hr survival after prolonged manual cardiopulmonary resuscitation (CPR) was investigated in 26 morphine-anesthetized dogs (17 to 30 kg). After placement of aortic and right atrial micromanometers and induction of ventricular fibrillation, manual CPR was commenced immediately and continued for 30 min. One group of 13 dogs underwent manual CPR at a compression rate of 60/min, and the other group at a rate of 120/min. The compression durations in the two groups were not significantly different (51.7 +/- 1.8% at 60/min vs 51.6 +/- 1.9% at 120/min). No drugs other than sodium bicarbonate were administered during CPR. A maximum of three attempts was permitted to defibrillate the heart. Successfully defibrillated animals were followed for 24 hr, during which time no treatment, other than naloxone, was given to reverse the effects of morphine. Arterial blood pH, PCO2, and PO2 were not significantly different in the two groups throughou...
Laser probe ablation of normal and atherosclerotic human aorta in vitro: a first thermographic and histologic analysis.
Authors: A JWelch, A BBradley, J HTorres, MMotamedi, J JGhidoni, J APearce, HHussein, R AO'Rourke
Journal: Circulation (1987)

The metal-tipped optical fiber or   has been extensively studied in animal preparations in vivo and in human clinical trials of revascularization. The aim of this study was to evaluate the thermal characteristics of laser probe tissue ablation and to contrast the vascular tissue response to exposure to the laser probe and bare optical fiber. A 2 mm laser probe was heated with up to 4 W of argon-ion laser irradiation and applied to six postmortem strips of human nonatherosclerotic aorta as well as to five atherosclerotic aortic specimens. Surface temperature maps of the laser probe and of the vascular tissue in air were obtained via 8 to 12 micron thermographic imaging. Laser probe temperature was additionally monitored via thermocouples. Two strips each of normal and diseased aorta were irradiated directly with the bare optical fiber. Thus a total of 43 laser probe application sites and 19 bare fiberoptic laser irradiation sites on a total of 15 aortic strips were analyzed both thermographical...
The mechanisms of supraventricular tachycardia in children.
Authors: P CGillette
Journal: Circulation (1976)

The mechanisms of supraventricular tachycardia were investigated in 35 children. Intracardiac electrograms including His bundle potentials were recorded. Atrial pacing and single premature atrial stimuli were performed in the right atrium. Tachycardia was observed and the mechanism elucidated in 33 patients. The atrial activation sequence during tachycardia, including high right atrium, low lateral right atrium, low septal right atrium, and left atrium, together with the ability to initiate or terminate the tachycardia with premature stimuli, were keys to defining the mechanisms. The observed mechanisms included atrioventricular (A-V) node reentry (8), sino atrial node re-entry (5), re-entry through manifest or concealed lateral anomalous pathway (8), re-entry through A-V node bypasses (3), and atrial (7) and junctional (2) ectopic focuses. The frequency of the various mechanisms of SVT is more varied in children than adults, with ectopic mechanisms being more common in children.
Microvascular pressures and resistances in the left ventricular subepicardium and subendocardium.
Authors: W MChilian
Journal: Circulation Research (1991)

These experiments tested the hypothesis that differences in the distribution of subepicardial and subendocardial microvascular resistances may alter the transmural distributions of microvascular pressures. Isolated blood- and physiological saline-perfused porcine hearts were surgically incised to enable exposure of the subendocardial and subepicardial microcirculations. Microvascular pressures were measured during cardiac arrest and maximal vasodilation at various perfusion pressures to formulate relations between perfusion pressure and microvascular pressure in the different subendocardial (both free wall and papillary muscle) and subepicardial segments. Measurements of arteriolar and venular pressures in both myocardial regions were performed in comparably sized vessels (80-120 microns in diameter). At a coronary perfusion pressure of 100 mm Hg, subendocardial arteriolar and venular pressures were 60 +/- 4 and 33 +/- 3 mm Hg, respectively. In contrast, at the same coronary perfusion pressure, arteriolar...
Supplementary Information on pH, Hyperthermia, and Cell Survival: Tumor Hyperacidification and Multistep Cancer Therapy—Reply
Authors: M. L. Freeman, W. C. Dewey, L. E. Hopwood
Journal: JNCI Journal of the National Cancer Institute (1978)

Journal Article Supplementary Information on pH, Hyperthermia, and Cell Survival: Tumor Hyperacidification and Multistep Cancer Therapy—Reply Get access JNCI: Journal of the National Cancer Institute, Volume 61, Issue 1, July 1978, Page 4, https://doi.org/10.1093/jnci/61.1.4 Published: 01 July 1978
Actions of vasoactive intestinal peptide and neuropeptide Y on the pacemaker current in canine Purkinje fibers.
Authors: FChang, HYu, I SCohen
Journal: Circulation Research (1994)

We have investigated the actions of vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY) on the pacemaker current (I(f)) in canine Purkinje fibers. On voltage pulses to the middle of the I(f) activation range, VIP reversibly increases I(f), whereas NPY reversibly decreases I(f). A three-pulse voltage protocol suggests that VIP shifts I(f) activation in the positive direction and that NPY shifts I(f) activation in the negative direction on the voltage axis without changing maximal I(f) conductance. These effects of VIP and NPY on I(f) are exerted through their specific peptide receptors, since the effects are blocked by VIP and NPY receptor antagonists. VIP and NPY are colocalized in cardiac parasympathetic and sympathetic nerve endings, respectively, and can be released preferentially on high and long-lasting nerve stimulation. Given this colocalization and frequency-dependent release, these results suggest a role for these neuropeptides in controlling cardiac I(f) and consequently heart rate.
Modified Endoscopic Ultrasound-Guided Rendezvous Technique For Faster And Safer Access To Narrow Bile Duct: Feasibility Assessment Study
Authors: J Samanta, G Muktesh, A Chowdhury, H Kumar, V Gupta, TD Yadav, R Kochhar
Journal: Endoscopy (2021)

Aims Endoscopic ultrasound (EUS) guided rendezvous technique (EUS-RV) is one of the salvage techniques for biliary access in cases of failed ERCP. Extra-hepatic approach with tapered lower end of common bile duct (CBD) can be technically challenging. We evaluated a modification of the trans-duodenal technique in benign biliary disease with narrow lower CBD.
Transfusion-Associated Graft-versus-Host Disease
Authors: Jane F. Desforges, Kenneth C. Anderson, Howard J. Weinstein
Journal: New England Journal of Medicine (1990)

Graft-versus-host disease is commonly observed after allogeneic bone marrow transplantation but rarely recognized after transfusion or solid-organ transplantation.1 2 3 Transfusion-associated graft-versus-host disease can occur in immunosuppressed recipients (e.g., in infants with congenital immunodeficiency syndromes and bone marrow-transplant recipients); there are also recent reports of graft-versus-host disease in immunocompetent transplant recipients.4 5 6 7 8 9 10 11 The chief clinical manifestations of graft-versus-host disease are fever and skin rash, which usually begins as a central erythematous, maculopapular eruption, spreads to the extremities, and may progress in severe cases to generalized erythroderma and the formation of bullae. Other manifestations include anorexia, nausea, vomiting, and watery or bloody diarrhea, with . . .
Cardiac metabolsim: its contributions to alcoholic heart disease and myocardial failure.
Authors: R JBing
Journal: Circulation (1978)

Changes in cardiac metabolism in myocardial failure and after alcohol ingestion are discussed. The main effect of alcohol ingestion is loss of cardiac contractility. Since heart muscle does not contain alcohol dehydrogenase, its toxicity is probably the result of a direct toxic effect of ethanol and acetaldehyde on the myocardial cell, possibly involving various membrane systems. Alcohol inhibits mitochondrial respiration and the activity of enzymes in the tricarboxylic acid cycle, and its interferes with both mitochondrial calcium uptake and binding. Ethanol profoundly affects myocardial lipid metabolism. Acetaldehyde diminishes myocardial protein synthesis and inhibits Ca++-activated myofibrillar ATPase. In myocardial failure, a series of possibilities may be responsible for the loss of contractility. Excitation-contraction coupling could be disturbed at the level of the sarcolemma, at the sarcoplasmic reticulum, at the mitochondria, and between calcium and the regulatory proteins. Deficiencies in Ca++ ...
The Workgroup Serrated Polyps And Polyposis (Wasp) Classification For Optical Diagnosis Of Diminutive Colorectal Polyps Using Iscan
Authors: E Soons, T Bisseling, C van der Post, I Nagtegaal, Y Hazewinkel, P Siersema
Journal: Endoscopy (2021)

Aims The Workgroup Serrated Polyps and Polyposis (WASP) classification system can be used for the endoscopic differentiation of adenomas (ADs), hyperplastic polyps and sessile serrated lesions (SSLs) and was developed for use with narrow band imaging. The aim of this study was to improve the diagnostic accuracy of diminutive colorectal polyps, when applying the WASP classification using iScan (Pentax).
Calcium transport properties of cardiac sarcoplasmic reticulum from cardiomyopathic Syrian hamsters (BIO 53.58 and 14.6): evidence for a quantitative defect in dilated myopathic hearts not evident in hypertrophic hearts.
Authors: J TWhitmer, PKumar, R JSolaro
Journal: Circulation Research (1988)

Calcium uptake was measured in homogenates and microsomal preparations enriched in sarcoplasmic reticulum vesicles isolated from hearts of hypertrophic (BIO 14.6) and dilated (BIO 53.58) cardiomyopathic as well as control (F1B) Syrian hamsters at 3, 7, 9, and 11 months of age. Calcium uptake studies were done using the Millipore filtration technique under conditions known to restrict transport to the sarcoplasmic reticulum. Steady-state calcium uptake capacity was used as a measure of the relative amounts of sarcoplasmic reticulum in homogenates prepared from individual hearts. At 3 months of age, there were no differences in calcium uptake in homogenates from control or myopathic hearts. However, by 9 months, although calcium uptake of homogenates from control and hypertrophic hearts was the same, calcium uptake by homogenates from dilated hearts was significantly depressed both in initial rate and capacity. Similar trends were seen in the microsomal vesicle preparations, but the decrease in calcium upta...
Local anesthetics and the role of sodium in the force development by canine ventricular muscle and purkinje fibers.
Authors: MVassalle, MBhattacharyya
Journal: Circulation Research (1980)

We studied the effects of the local anesthetics, procaine and benzocaine, on the action potential and force of canine ventricular muscle and Purkinje fibers. In ventricular muscle, procaine often shifted the plateau to a more positive value and increased the force of contraction, whereas benzocaine shortened the action potential and decreased contractile force. In Purkinje fibers, both local anesthetics reduced contractile force and decreased the duration of the action potential markedly. In ventricular muscle fibers norepinephrine potentiated the positive inotropic effect of procaine and changed the effects of benzocaine from a negative to a positive inotropic effect. The potentiating effect of procaine on contraction was eliminated by propranolol. In the presence of norepinephrine (and the absence of propranolol), in Purkinje fibers both anesthetics decreased force but less than in the absence of norepinephrine. In the presence of tetrodotoxin (TTX) and norepinephrine, procaine and benzocaine increased ...
Incremental Yield of Artificial Intelligence in Follow-Up Screening Colonoscopies – an Interim Analysis
Authors: SM Milluzzo, P Cesaro, C Hassan, EV Pesatori, S Piccirelli, F Catino, A Quadarella, N Olivari, L Minelli Grazioli, M Codazzi, A Bizzotto, MR Schivardi, C Spada
Journal: Endoscopy (2021)

Aims Although colonoscopy is the gold standard for detection of precancerous colonics lesions, they are still missed and this is directly related with an increased risk of interval colorectal cancer. To improve the diagnostic performances of colonoscopy, novel technologies have been recently developed, in particular Artificial Intelligence (AI). The objective of this study was to compare the diagnostic yield obtained by using the GI Genius (Medtronic, Minneapolis, USA) AI software during colonoscopy to the yield obtained by the standard colonoscopy (SC).
Relative dipolar behavior of the equivalent T wave generator: quantitative comparison with ventricular excitation in the rabbit heart.
Authors: D ABrody, D MMirvis, R EIdeker, J WCox, F WKeller, R ALarsen, J PBandura
Journal: Circulation Research (1977)

We studied the relative dipolar and nondipolar content of signal energy throughout ventricular excitation and recovery in 34 isolated, perfused rabbit hearts, suspended in an electrolyte-filled spherical chamber. Computer-processed signals were derived from 20 evenly spaced tank-surface electrodes, and a single, moving, equivalent cardiac dipole generator was optimally fitted to the recorded potentials for each 1-msec sampling interval. Superimposed, time-based plots of signal energy for the 34 preparations showed ventricular excitation to be strikingly more nondipolar than was recovery. In terms of the summed square ratio of nondipolar residual energies, overall nondipolarity of QRS exceed that of ST-T by 41%. Furthermore, the maximum instantaneous ratio during QRS was considerably greater than during the ST-T. Evaluation of paired differences, comparing nondipolar behavior throughout QRS with all of ST-T, proved highly significant (P less than .005). We also found that in contrast to the considerable mo...
Mechanism-specific effects of adenosine on atrial tachycardia.
Authors: E DEngelstein, NLippman, K MStein, B BLerman
Journal: Circulation (1994)

BACKGROUNDRecent reports suggest that adenosine, in addition to terminating supraventricular tachycardia involving the atrioventricular (AV) node, may have antiarrhythmic effects on atrial tachycardia. The electrophysiological effects of adenosine on supraventricular tissue include shortening of action potential duration in atrial myocytes mediated by the potassium current, IKACh,Ado; shortening of action potential duration and hyperpolarization in sinus node cells; and anti-adrenergic electrophysiological effects resulting from inhibition of adenylyl cyclase. We therefore hypothesized that the response of atrial tachycardia to adenosine would be mechanism specific, with termination of atrial tachycardia due to sinus node reentry or cAMP-mediated triggered activity, transient suppression of automatic atrial tachycardia, and an absence of antiarrhythmic effect on tachycardia due to intraatrial reentry.METHODS AND RESULTSAdenosine (mean +/- SD, 143 +/- 54 micrograms/kg IV) was administered to 27 patients (5...
Transmural activations and stimulus potentials in three-dimensional anisotropic canine myocardium.
Authors: D WFrazier, WKrassowska, P SChen, P DWolf, N DDanieley, W MSmith, R EIdeker
Journal: Circulation Research (1988)

Epicardial and endocardial pacing are widely used, yet little is known about the three-dimensional distribution of potentials generated by the pacing stimulus or the spread of activation from these pacing sites. In six open-chest dogs, simultaneous recordings were made from 120 transmural electrodes in 40 plunge electrodes within a 35 X 20 X 5-mm portion of the right ventricular outflow tract during epicardial and endocardial pacing at a strength of twice diastolic threshold and at 1 mA. The magnitude of extracellular potentials generated by the stimulus and the activation times were compared in regions proximal (less than 10-12 mm) and distal to the pacing site. Local fiber orientation was histologically determined at each recording electrode. For endocardial pacing, endocardial potentials were larger than epicardial potentials only in the proximal region (p less than 0.001); while in the distal region, epicardial potentials were larger (p less than 0.001), and endocardial activation occurred earlier tha...
Relative significance of endothelium and internal elastic lamina in regulating the entry of macromolecules into arteries in vivo.
Authors: M SPenn, G MSaidel, G MChisolm
Journal: Circulation Research (1994)

A role for the internal elastic lamina (IEL), which separates the intima and media of an artery wall, as a restrictive barrier to macromolecular movement has been suggested in atherosclerotic lesion development or restenosis during angioplasty. The permeability coefficient of the IEL, however, has never been quantified in unperturbed vessels in vivo. Using a newly developed technique, we measured the concentration distributions in both intima and media of cationic (pI approximately 8.5) and anionic (pI approximately 6.3) isozymes of the 44-kD macromolecule horseradish peroxidase (HRP). Two mathematical models of arterial wall transport differing in their resolution of the intima were required to simulate the concentration distribution data and to estimate the parameters of interest. Optimal estimates of the permeability coefficients of the endothelium (PE) and IEL (PIEL) to HRP were determined by the best least-squares fit of the two models to experimental data. These estimates (anionic: PE = 0.050 +/- 0....