tbuckley/cabot-search huggingface dataset:
Identification of Dysplasia in the Barrett’S Esophagus Using an Endocytoscopy Classification System: Preliminary Results of a Prospective Comparison Between Clinicians and Artificial Intelligence
Authors: JJH van der Laan, JA van der Putten, X Zhao, I Schmidt, RY Gabriëls, A Karrenbeld, FTM Peters, J Westerhof, F Van der Sommen, WB Nagengast
Journal: Endoscopy (2021)

Aims To investigate the feasibility of endocytoscopy (EC) in differentiating dysplastic from non-dysplastic tissue in the Barrett’s esophagus (BE) in vivo, performance of clinicians and a computer-aided diagnosis (CADx) algorithm were assessed and compared with each other. Ultimately, the potential of the implementation of CADx will be determined during a test in which clinicians can use the help of the CADx.
Inhibition of coronary blood flow by a vascular waterfall mechanism.
Authors: J MDowney, E SKirk
Journal: Circulation Research (1975)

The mechanism whereby systole inhibits coronary blood flow was examined. A branch of the left coronary artery was maximally dilated with an adenosine infusion, and the pressure-flow relationship was obtained for beating and arrested states. The pressure-flow curve for the arrested state was shifted toward higher pressures and in the range of pressures above peak ventricular pressure was linear and parallel to that for the arrested state. Below this range the curve for the beating state converged toward that for the arrested state and was convex to the pressure axis. These results were compared with a model of the coronary vasculature that consisted of numerous parallel channels, each responding to local intramyocardial pressure by forming vascular waterfalls. When intramyocardial pressure in the model was assigned values from zero at the epicardium to peak ventricular pressure at the endocardium, pressure-flow curves similar to the experimental ones resulted. Thus, we conclude that systole inhibits corona...
Paradoxical embolism. A diagnostic challenge and its detection during life.
Authors: T OCheng
Journal: Circulation (1976)

Two cases of paradoxical embolism, one with recurrent cerebral embolism and one with brachial and coronary embolism and both associated with pulmonary embolism, were diagnosed during life. Although there was neither pulmonary hypertension nor intracardiac shunt present at the time of cardiac catheterization in both cases, the presence of a patent foramen ovale with an interatrial right-to-left shunt was demonstrated by a simple ascorbate dilution technique following a Valsalva maneuver. Each patient was treated by surgical interruption of the inferior vena cava and did well. Paradoxical embolism should be included in the differential diagnosis of arterial embolism for which there is no obvious source, especially when there is also evidence of venous thrombosis or pulmonary embolism.
Opioids in cerebrospinal fluid in hypotensive newborn pigs.
Authors: W MArmstead, RMirro, D WBusija, D MDesiderio, C WLeffler
Journal: Circulation Research (1991)

This study was designed to determine if opioids were detectable in cerebrospinal fluid (CSF) and if these concentrations were altered by hemorrhagic hypotension. This study was further designed to determine the effects of topically administered opioids on pial arteriolar diameter during normotension and hypotension. Closed cranial windows were used to determine pial arteriolar diameter. Periarachnoid cortical and cisterna magna CSF was collected from piglets during normotension and hypotension (systemic arterial pressure decreased from 63 +/- 1 to 33 +/- 1 mm Hg). Opioid profiles were assessed qualitatively by radioreceptor assay, and individual opioids were measured quantitatively by radioimmunoassay. Periarachnoid cortical and cisterna magna CSF methionine enkephalin-, leucine enkephalin-, dynorphin-, and beta-endorphin-like receptor active values all were increased by hypotension. When quantified by radioimmunoassay, periarachnoid cortical CSF values for methionine enkephalin-like immunoreactivity were...
Cytotoxic effects of a recombinant chimeric toxin on rapidly proliferating vascular smooth muscle cells.
Authors: S EEpstein, C BSiegall, SBiro, Y MFu, DFitzGerald, IPastan
Journal: Circulation (1991)

BACKGROUNDRestenosis after percutaneous transluminal coronary angioplasty is associated with activation of medial smooth muscle cells (SMCs); they proliferate, migrate to the subintima, and narrow the vessel lumen. Cancer cells often express more cell surface receptors than do normal cells. This has allowed tumor cells to be specifically targeted using cytotoxic agents. We have examined whether a similar concept can be applied to rapidly proliferating but nontransformed SMCs. Pseudomonas exotoxin (PE; MW, 66 kDa) is a potent toxin that kills cells by inhibiting protein synthesis; its toxicity is diminished when its cell recognition domain is deleted to produce a 40-kDa protein (PE40).METHODS AND RESULTSA complementary DNA encoding transforming growth factor alpha (TGF alpha) was ligated to that encoding PE40 and the chimeric toxin TGF alpha-PE40, which is cytotoxic to cancer cells displaying epidermal growth factor (EGF) receptors, was expressed in Escherichia coli. The ability of this toxin to kill proli...
Modulation of parasystolic activity by nonparasystolic beats.
Authors: G JNau, A EAldariz, R SAcunzo, M SHalpern, J MDavidenko, M VElizari, M BRosenbaum
Journal: Circulation (1982)

We studied 12 patients with ventricular parasystole in whom pacemaker activity could be modulated by nonparasystolic beats (NPBs). In six patients (group 1) in whom the intrinsic parasystolic cycle length (XX interval) was obtained without interposed NPBs, we found that NPBs falling during the first half of the cycle prolonged the XRX interval (containing one NPB) and that NPBs falling during the second half of the cycle abbreviated the XRX interval; both effects were maximal when NPBs fell close to the middle of the cycle and were separated by a reversal point. However, because of mutual interference between parasystolic beats and NPBs, only 13.2-43.4% of the parasystolic cycle could be effectively scanned. We also found that the XRX and RX intervals were linearly related. This relationship served to establish that in six patients in whom the XX interval was not obtained (group 2), modulation showed a similar behavior, although neither the reversal point nor the sense of the modulation could be determine...
Influence of alteration in preload on the pattern of left ventricular diastolic filling as assessed by Doppler echocardiography in humans.
Authors: M FStoddard, A CPearson, M JKern, JRatcliff, D GMrosek, A JLabovitz
Journal: Circulation (1989)

We examined the influence of alterations in preload on pulsed Doppler indexes of left ventricular diastolic function in 50 patients including 12 without cardiovascular disease, 29 with coronary artery disease, and nine with critical aortic stenosis. Micromanometer left ventricular pressure was recorded simultaneously with pulsed Doppler echocardiography of left ventricular inflow and M-mode echocardiography of left ventricular diameter. Chamber stiffness constants, kd and kv, were obtained from the diastolic pressure-diameter and pressure-volume relations, respectively. Relaxation was measured by the isovolumic relaxation time constants, TL and TD, derived from the exponential left ventricular pressure decay and maximum negative dP/dt. In 41 patients after nitroglycerin treatment, left ventricular end-diastolic pressure decreased from 18 +/- 5 to 13 +/- 4 mm Hg (p less than 0.001). The ratio of peak early to peak atrial filling velocities and time-velocity integral ratios decreased from 1.08 +/- 0.57 to 0...
Compensating Physicians for Telephone Calls
Authors: Hunter Heath
Journal: JAMA (1995)

<h3>To the Editor.</h3> —Dr Sorum's<sup>1</sup>Commentary is spot on. When I call my attorney, I can hear the meter clicking in the background, and the bill arrives within days after the telephone call. The time is overdue for physicians to receive compensation for the extraordinary amount of "free services" that we render over the wire. The time consumed is real time, the judgments require expertise, the advice given has consequences, and the courts have established our liability for the consequences of those calls. Even as an academic physician with a limited practice, I find myself spending an extraordinary amount of time in the evening and on weekends making telephone calls to patients, either because the patients are unreachable during the workday or because I simply have no other time to make the calls. The burden certainly would be lighter were I to receive modest compensation. I hope Sorum's proposal
Effect of chronic myocardial infarction on vagal cardiopulmonary baroreflex.
Authors: A JMinisi, M DThames
Journal: Circulation Research (1989)

Sensory endings in the left ventricle are damaged by acute myocardial infarction. The goal of our experiments was to determine whether reflexes that originate in the heart are impaired by chronic myocardial infarction. Inferoposterior (n = 11) or anterior (n = 10) infarction was produced in dogs by ligation and intracoronary injection of rapidly hardening latex into either the proximal left anterior descending or left circumflex coronary arteries. Four weeks after infarction, the changes in renal sympathetic nerve activity induced by phenylephrine infusion, hemorrhage, and volume expansion were assessed before and after sinoaortic baroreceptor denervation. The results in infarct dogs were compared with the results in 11 sham-operated dogs. With arterial baroreceptors intact, baroreflex sensitivity (defined as the percent change in renal nerve activity per millimeter of mercury change in mean pulmonary artery wedge pressure) was similar in all groups of dogs. Following sinoaortic denervation, dogs with ant...
Increased expression and regional differences of atrial myosin light chain 1 in human ventricles with old myocardial infarction. Analyses using two monoclonal antibodies.
Authors: KNakao, HYasue, KFujimoto, MJougasaki, HYamamoto, YHitoshi, KTakatsu, EMiyamoto
Journal: Circulation (1992)

BACKGROUNDThis study was designed to examine the expression of atrial/fetal-type myosin light chain 1 (ALC1) in human ventricles with old myocardial infarction and in control hearts.METHODS AND RESULTSThe expression of immunoreactive (ir) ALC1 was examined in the subendocardial and subepicardial myocardium of the infarcted and the noninfarcted regions in the left ventricles with old myocardial infarction (n = 12) and of the control left ventricles (n = 8). For the analysis, we prepared two monoclonal antibodies, KA1 and KB1, that were specific for only ALC1 and for both ALC1 and ventricular myosin light chain 1 (VLC1), respectively. The ir-ALC1 expression ratio [ALC1/(ALC1 + VLC1), %] of the subendocardial myocardium, determined densitometrically by Western blotting with KB1, was significantly higher in the infarcted region (11.4 +/- 7.3%) than in the noninfarcted region (4.7 +/- 2.3%, p < 0.001) and the control ventricle (1.0 +/- 1.5%, p < 0.0001). In the infarcted region, the subendocardial myocardium c...
Clarifying Assumptions and Outcomes in Cost-Effectiveness Analyses—Reply
Authors: John R. Goffin, William M. Flanagan, William K. Evans
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
Effects of hemorrhage on renal nerve activity in conscious dogs.
Authors: HMorita, S FVatner
Journal: Circulation Research (1985)

We studied the effects of slow continuous hemorrhage (0.5 ml/kg per min) on measurements of arterial and left atrial pressures, and renal nerve activity in conscious dogs with all reflexes intact, or after sinoaortic baroreceptor denervation, cardiac denervation, or sinoaortic baroreceptor denervation plus vagal denervation. In intact dogs, mean arterial pressure remained relatively constant at 101 +/- 4 mm Hg until 20 +/- 4 ml/kg of hemorrhage, when renal nerve activity increased by 211 +/- 53%. At 39 +/- 2 ml/kg hemorrhage, mean arterial pressure fell by 48 +/- 3 mm Hg, and renal nerve activity returned to the prehemorrhage control level. Cardiac denervation did not affect the response of mean arterial pressure to hemorrhage, whereas, after sinoaortic baroreceptor denervation and sinoaortic baroreceptor plus vagal denervation, mean arterial pressure remained at its control level only through 8 +/- 1 and 4 +/- 1 ml/kg hemorrhage, respectively. The increases in renal nerve activity during nonhypotensive h...
Mechanics of postextrasystolic potentiation in normal subjects and patients with valvular heart disease.
Authors: TWisenbaugh, SNissen, ADeMaria
Journal: Circulation (1986)

To determine the relative influence of preload, afterload, and inotropic state on postextrasystolic potentiation (PESP) of ventricular performance in man, we computed angiographic left ventricular volume and wall stress frame by frame for a control and potentiated beat in each of 31 patients. In 10 normal subjects, PESP increased ejection fraction by 14%, while left ventricular end-diastolic volume increased by 8% (p less than .001) and end-systolic stress fell by 21% (p less than .005). Enhanced diastolic filling (+6%, p less than .005) with a small decline in end-systolic stress (-8%, p = NS) likewise contributed to potentiation of ejection fraction (+14%, p less than .001) in seven patients with aortic stenosis. Diastolic filling was not significantly augmented during the compensatory pause in six patients with isolated mitral regurgitation, nor in eight patients with aortic regurgitation (+2%, p = NS for both). Although afterload tended to fall for potentiated beats in patients with aortic (-11%, p = ...
Relation of smoking with carotid artery wall thickness and stenosis in older adults. The Cardiovascular Health Study. The Cardiovascular Health Study (CHS) Collaborative Research Group.
Authors: G STell, J FPolak, B JWard, S JKittner, P JSavage, JRobbins
Journal: Circulation (1994)

BACKGROUNDCigarette smoking has been associated with increased risk of atherosclerotic diseases in hospital-based studies and in studies of middle-aged populations but not in population-based studies of older adults with and without clinical cardiovascular disease.METHODS AND RESULTSWe investigated the relation of smoking to carotid artery atherosclerotic disease, expressed as intimal-medial wall thickness and arterial lumen narrowing (stenosis) measured by ultrasound. Subjects were 5116 older adults participating in the baseline examination of the Cardiovascular Health Study, a community-based study of cardiovascular diseases in older age. With increased smoking there was significantly greater internal and common carotid wall thickening and internal carotid stenosis: current smokers > former smokers > never-smokers; for instance, the unadjusted percent stenosis was 24%, 20%, and 16%, respectively (P < .0001). A significant dose-response relation was seen with pack-years of smoking. These findings persist...
A life table and Cox regression analysis of patients with combined proximal left anterior descending and proximal left circumflex coronary artery disease: non-left main equivalent lesions (CASS).
Authors: B RChaitman, KDavis, L DFisher, M GBourassa, M BMock, JLespérance, W JRogers, DFray, D HTyras, M PJudkins
Journal: Circulation (1983)

Combined proximal  anterior descending and proximal  circumflex artery stenoses greater than or equal to 70% have been referred to as left main  lesions. We compared the survival rates of medically treated patients who have this type of coronary anatomic characteristics with the survival rates of patients who have  main coronary artery stenoses greater than or equal to 70% by use of a stratified life table approach and a Cox regression model. Comparison of the patients with  main coronary artery stenoses with those who have  main equivalent lesions by use of life table analysis and three different calculations of patient exposure time revealed a poorer prognosis for the patients who had  main coronary artery disease (p less than or equal to .04 for all three methods). The stepwise Cox analysis also determined that patients who had  main artery stenoses had a significantly poorer prognosis than patients who had  main equivalent coronary disease (p = .002), even a...
Coronary blood flow during cardiopulmonary resuscitation in swine.
Authors: R FBellamy, L RDeGuzman, D CPedersen
Journal: Circulation (1984)

Recent papers have raised doubt as to the magnitude of coronary blood flow during closed-chest cardiopulmonary resuscitation. We will describe experiments that concern the methods of coronary flow measurement during cardiopulmonary resuscitation. Nine anesthetized swine were instrumented to allow simultaneous measurements of coronary blood flow by both electromagnetic cuff flow probes and by the radiomicrosphere technique. Cardiac arrest was caused by electrical fibrillation and closed-chest massage was performed by a Thumper (Dixie Medical Inc., Houston). The chest was compressed transversely at a rate of 66 strokes/min. Compression occupied one-half of the massage cycle. Three different Thumper piston strokes were studied: 1.5, 2, and 2.5 inches. Mean aortic pressure and total systemic blood flow measured by the radiomicrosphere technique increased as Thumper piston stroke was lengthened (mean +/- SD): 1.5 inch stroke, 23 +/- 4 mm Hg, 525 +/- 195 ml/min; 2 inch stroke, 33 +/- 5 mm Hg, 692 +/- 202 ml/min...
Comparative effects of nitroprusside and pinacidil on myocardial blood flow and infarct size in awake dogs with acute myocardial infarction.
Authors: NImai, C SLiang, C KStone, SSakamoto, W BHood
Journal: Circulation (1988)

The effect of nitroprusside in limiting myocardial infarct was compared with that of pinacidil, a new antihypertensive agent with potent coronary vasodilator properties, in instrumented awake dogs subjected to 4 hr of left anterior descending coronary artery occlusion and 20 hr of reperfusion. Dogs were randomly assigned to receive intravenous normal saline, nitroprusside, or pinacidil beginning 40 min after the onset of coronary artery occlusion and continuing throughout the occlusion and the first hour of reperfusion. Nitroprusside and pinacidil were titrated to decrease mean aortic pressure by 25 mm Hg; normal saline had no effect on mean aortic pressure. Other systemic hemodynamic variables were not significantly altered by normal saline or nitroprusside, and myocardial blood flow did not change during normal saline infusion in normal and ischemic myocardium. In contrast, nitroprusside increased the blood flow and the endocardial/epicardial flow ratio in ischemic myocardium. This increase in ischemic ...
Angiotensin II stimulates NADH and NADPH oxidase activity in cultured vascular smooth muscle cells.
Authors: K KGriendling, C AMinieri, J DOllerenshaw, R WAlexander
Journal: Circulation Research (1994)

The signaling pathways involved in the long-term metabolic effects of angiotensin II (Ang II) in vascular smooth muscle cells are incompletely understood but include the generation of molecules likely to affect oxidase activity. We examined the ability of Ang II to stimulate superoxide anion formation and investigated the identity of the oxidases responsible for its production. Treatment of vascular smooth muscle cells with Ang II for 4 to 6 hours caused a 2.7 +/- 0.4-fold increase in intracellular superoxide anion formation as detected by lucigenin assay. This superoxide appeared to result from activation of both the NADPH and NADH oxidases. NADPH oxidase activity increased from 3.23 +/- 0.61 to 11.80 +/- 1.72 nmol O2-/min per milligram protein after 4 hours of Ang II, whereas NADH oxidase activity increased from 16.76 +/- 2.13 to 45.00 +/- 4.57 nmol O2-/min per milligram protein. The NADPH oxidase activity was stimulated by exogenous phosphatidic and arachidonic acids and was partially inhibited by the ...
Effectiveness of recombinant desulphatohirudin in reducing restenosis after balloon angioplasty of atherosclerotic femoral arteries in rabbits.
Authors: I JSarembock, S DGertz, L WGimple, R MOwen, E RPowers, W CRoberts
Journal: Circulation (1991)

BACKGROUNDThe effectiveness of balloon angioplasty is limited by a restenosis rate of approximately 30%. Recombinant desulphatohirudin (r-hirudin [CGP 39393]) has been found to be highly effective in preventing acute platelet-rich thrombosis after deep arterial injury as compared with heparin.METHODS AND RESULTSThis study evaluated the effect of intravenous r-hirudin, a selective inhibitor of thrombin, on restenosis after balloon angioplasty in 29 rabbits. Focal femoral atherosclerosis was induced by air desiccation endothelial injury followed by a 2% cholesterol diet for 1 month. At angioplasty (2.5-mm balloon with three 60-second, 10-atm inflations 60 seconds apart), the rabbits received heparin (150 units/kg bolus, n = 16) or r-hirudin (1 mg/kg bolus followed by infusions of 1 mg/kg for the first hour and 0.5 mg/kg for the second hour, n = 13). Angiograms performed before and after angioplasty and before death were analyzed quantitatively by a blinded observer. Rabbits were killed 2 hours (n = 14) or 2...
Volume-dependent effects of positive airway pressure on intracavitary left ventricular end-diastolic pressure.
Authors: R VDitchey
Journal: Circulation (1984)

To test the hypothesis that the effects of positive end-expiratory airway pressure (PEEP) on intracavitary left ventricular end-diastolic pressure (LVEDP) depend on the ventricular filling conditions under which PEEP is applied, the effects of PEEP on pressure in and around the left ventricle were determined before and after stepwise expansion of intravascular blood volume in 10 closed-chest dogs. Over a range of 0 to 20 cm of water, PEEP progressively increased both intrapericardial and intracavitary right ventricular end-diastolic pressures. These increases in pressure around the left ventricle were approximately linear and were relatively unaffected by volume loading. At the same time, PEEP always decreased transmural LVEDP by decreasing ventricular filling. However, transmural LVEDP fell more when ventricular volume was initially large, due to the nonlinear relationship between left ventricular transmural pressure and volume. As a result, intracavitary LVEDP (which reflected the sum of decreased trans...