tbuckley/cabot-search huggingface dataset:
Detection of myocardial scar tissue by M-mode echocardiography.
Authors: SRasmussen, B CCorya, HFeigenbaum, S BKnoebel
Journal: Circulation (1978)

Wall thicknesses were measured and echo densities were evaluated from the left ventricular echograms of 182 patients. The echogram was considered to reflect scar tissue when 1) either the interventricular septum, the posterior left ventricular wall or the anterior left ventricular wall was less than 7 mm thick in mid-diastole and was more echo-producing than its opposing wall or another area of the same wall in a sector scan, or 2) an area of myocardium was 30% less thick than an adjacent area within a sector scan. Myocardial scarring was diagnosed by echocardiography in 52 of the 182 patients. The echocardiographic presence or absence of scarring was confirmed in 95% (173 of 182) of cases, 34 cases by microscopic examination and 139 by surgical appearance. This study shows that M-mode echocardiography is both a sensitive and specfic method for detecting myocardial scar tissue.
Abnormal Parietal Cortex Activation During Working Memory in Schizophrenia: Verbal Phonological Coding Disturbances Versus Domain-General Executive Dysfunction
Authors: Deanna Barch
Journal: American Journal of Psychiatry (2007)

Objective: The goal of this study was to determine whether the regions of the prefrontal and parietal cortices showing abnormal activation among individuals with schizophrenia during working memory tasks are associated with either 1) phonological coding processes that may be specific to verbal tasks (i.e., ventral prefrontal and parietal cortices) or 2) domain-general executive processes engaged by verbal and nonverbal tasks (i.e., dorsal prefrontal and parietal cortices). Method: The participants were 57 medicated individuals with schizophrenia and 120 healthy subjects. Functional magnetic resonance imaging was used to scan all participants during performance of verbal and nonverbal 2-back working memory tasks. Results: In the healthy subjects there was similar bilateral dorsal prefrontal and inferior parietal cortex activation for both the verbal and nonverbal working memory tasks, but greater left ventral prefrontal and parietal cortex activation during verbal compared to nonverbal working memory. Individuals with schizophrenia showed bilateral deficits in dorsal frontal and parietal activation during both verbal and nonverbal working memory tasks. They also demonstrated the typical pattern of greater activity for verbal, as compared to nonverbal, working memory in ventral prefrontal and parietal regions, although they showed less verbal superiority in a left ventral prefrontal region. Conclusions: These results support the hypothesis that working memory deficits in individuals with schizophrenia reflect deficits in activation of brain regions associated with the central executive components of working memory rather than domain-specific storage buffers.
Circadian variation and triggers of onset of acute cardiovascular disease.
Authors: J EMuller, G HTofler, P HStone
Journal: Circulation (1989)

Information obtained during the past decade suggests the need to reexamine the possibility that the onset of myocardial infarction and sudden cardiac death is frequently triggered by daily activities. The importance of physical or mental stress in triggering onset of coronary thrombosis is supported by the findings that 1) the frequencies of onset of myocardial infarction, sudden cardiac death, and stroke show marked circadian variations with parallel increases in the period from 6:00 AM to noon, 2) transient myocardial ischemia shows a similar morning increase, and episodes are often preceded by mental or physical triggers, 3) a ruptured atherosclerotic plaque, often nonobstructive by itself, lies at the base of most coronary thrombi, 4) a number of physiologic processes that could lead to plaque rupture, a hypercoagulable state or coronary vasoconstriction, are accentuated in the morning, and 5) aspirin and beta-adrenergic blocking agents, which block certain of these processes, have been shown to preve...
Serotonin as an alternative transmitter in sympathetic nerves of large cerebral arteries of the rabbit.
Authors: ASaito, T JLee
Journal: Circulation Research (1987)

The distribution of serotonin (5-HT)-like immunoreactive (5-HT-LI) nerves and the potential role of 5-HT as a vasoconstrictor transmitter in large cerebral arteries of the rabbit were examined. 5-HT-LI fibers with weak immunofluorescence were observed in the anterior cerebral, middle cerebral, and basilar arteries when fixed by immersion after dissection from exsanguinated animals. The 5-HT-LI fibers, however, were not detected in these arteries when fixed either in vitro or in situ after first being perfused with Krebs solution in situ to flush the blood component from the lumen prior to dissection. In these arteries, 5-HT-LI nerve fibers with intense immunofluorescence, however, reappeared following incubation with 5-HT in vitro. The intensity of the 5-HT-LI fibers seemed to be proportional to the duration and 5-HT concentration during incubation. Following chronic surgical sympathectomy, 5-HT-LI fibers were not detected in arteries before or after incubation with 5-HT. Transmural nerve stimulation elic...
ESR1 gene amplification in breast cancer: a common phenomenon?
Authors: Hugo M Horlings, Anna Bergamaschi, Silje H Nordgard, Young H Kim, Wonshik Han, Dong-Young Noh, Keyan Salari, Simon A Joosse, Fabien Reyal, Ole Christian Lingjaerde, Vessela N Kristensen, Anne-Lise Børresen-Dale, Jonathan Pollack, Marc J van de Vijver
Journal: Nature Genetics (2008)
Radiofrequency catheter ablation of atriofascicular and nodoventricular Mahaim tracts.
Authors: H RGrogin, R JLee, MKwasman, L MEpstein, D JSchamp, M DLesh, M MScheinman
Journal: Circulation (1994)

BACKGROUNDSeveral mechanisms have been proposed to explain the pathogenesis of tachycardia in patients with  tracts. The tachycardia may involve antegrade conduction over an atriofascicular pathway with decremental properties or a nodofascicular pathway.METHODS AND RESULTSWe report six patients with recurrent episodes of preexcited tachycardia with findings consistent with Mahaim tract conduction. All patients exhibited decremental antegrade preexcited conduction with atrial pacing and a preexcited tachycardia with initial activation of the proximal right bundle branch. In four patients (group 1), atrial premature complexes (APCs) induced at the tricuspid annulus just after the inscription of the septal atrial electrogram and during left bundle branch block preexcited tachycardia advanced the next preexcited ventricular complex. In these patients, discrete  potentials were inscribed over the right anterolateral or lateral tricuspid annulus. Two patients (group 2) had evidence of dual atriove...
Treatment of paroxysmal supraventricular tachycardia in infancy with digitalis, adenosine-5'-triphosphate, and verapamil: a comparative study.
Authors: RGreco, BMusto, VArienzo, AAlborino, SGarofalo, FMarsico
Journal: Circulation (1982)

The treatment of paroxysmal supraventricular tachycardia (PSVT) in infancy with digitalis, adenosine triphosphate (ATP) and verapamil is reported. Treatment was successful in about 90% of the patients treated with ATP and verapamil and in 61--71% of the patients treated with digitalis (Lanatoside C). Verapamil terminated the tachycardia within 2 minutes of administration in most instances and ATP in less than 1 minute. Digitalis, however, took as long as 2 hours; it was therefore excluded as the drug of first choice in emergencies, and is better suited for treating patients with poor hemodynamics. Side effects with ATP are common but short-lived. With verapamil, side effects are rare, but may be serious if certain contraindications are not taken into account. Digitalis in the dose used in this trial rarely produced side effects. We conclude that ATP or verapamil is the drug of first choice for quick termination of PSVT in infancy.
Analysis of surgically-induced right bundle branch block pattern using intracardiac recording techniques.
Authors: R JSung, D MTamer, O LGarcia, ACastellanos, R JMyerburg, HGelband
Journal: Circulation (1976)

Using intracardiac recording techniques, His bundle (H) and right ventricular apical (RVA) electrograms were recorded in 16 patients with a postoperative electrocardiographic pattern of right bundle branch block (RBBB). Their ages ranged from 5 to 12 years (mean 6.9 years) at surgery and the follow-up period was 1 to 7 years (mean 2.7 years). All were asymptomatic and in sinus rhythm at the time of study. The P-A interval was normal in all and the A-H, H-V, and V-RVA intervals were prolonged in one, one, and six patients, respectively. The V-RNA interval was normal (less than or equal to 30 msec) in ten out of the 11 patients (91%) without associated left anterior hemiblock (LAH), indicating a physiologically intact main right bundle branch, and was abnormally lengthened (45-62 msec) in all five patients (100%) with associated LAH. These findings suggest that there are two subgroups of patients with surgicall-induced RBBB pattern and the measurement of the V-RVA interval in conjunction with the H-V interv...
The high-risk angina patient. Identification by clinical features, hospital course, electrocardiography and technetium-99m stannous pyrophosphate scintigraphy.
Authors: H GOlson, K PLyons, W SAronow, P JStinson, JKuperus, H JWaters
Journal: Circulation (1981)

We evaluated 193 consecutive unstable angina patients by clinical features, hospital course and electrocardiography. All patients were managed medically. Of the 193 patients, 150 (78%) had a technetium-99m pyrophosphate (Tc-PYP) myocardial scintigram after hospitalization. Of these, 49 (33%) had positive scintigrams. At a follow-up of 24.9 +/- 10.8 months after hospitalization, 16 of 49 patients (33%) with positive scintigrams died from cardiac causes, compared with six of 101 patients (6%) with negative scintigrams (p less than 0.001). Of 49 patients with positive scintigrams, 11 (22%) had had nonfatal myocardial infarction at follow-up, compared with seven of 101 patients (7%) with negative scintigrams (p less than 0.01). Age, duration of clinical coronary artery disease, continuing angina during hospitalization, ischemic ECG, cardiomegaly and a history of heart failure also correlated with cardiac death at follow-up. Ischemic ECG and a history of angina with a crescendo pattern also correlated with non...
Idiopathic Dilated Cardiomyopathy
Journal: New England Journal of Medicine (1995)

The mechanism by which afterload reduction increases left ventricular stroke volume while decreasing left ventricular filling pressure has not previously been established. In 15 patients with severe congestive heart failure due to ischemic or idiopathic di1ate.d cardiomyopathy, absolute ventricular volume, ejection fraction and total stroke volume from iadionuclide ventriculography were compared with thermodilution stroke volume before and after intensive afterload reduction with vasodilators and diuretics titrated to hemodynamic goals. After 48 to 72 hours, pulmonary artery wedge pressure decreased from 32 f 8 to 16 f 4 mm kg and systemic vascular resistance from 1,960 f 700 to 1,200 f 400 dynes s cmm5. End-diastolic volume decreased from 390 f 138 to 301 f 126 ml (p <O.Ol) and end-systolic votume from 316 f 127 to 241 f 111 (p <O.Ol). Ejection fraction did not change and total stroke volume decreased from 74 f 22 to 59 f 20 ml (p <O.O!). Simultaneous forward stroke volume by thermodilution increased from 37 f 14 to 52 f 14 ml (p <O.Ol), and forward fraction increased from 0.55 f 0.40 to 0.96 f 0.42. Intensive reduction of ventricular filling pressure and systemic vascular resistance decreased total ventricular stroke volume by 20% but increased forward stroke volume by 40%. The major effect of intensive afterload reduction for severe congestive heart failure may be the reduction of ventricular volume and mitral regurgitation.
Gross Dissection of Liver for Hepatocellular Carcinoma Using AJCC Cancer Staging Manual 8th Edition: Anatomical and Practical Considerations
Authors: Marla Beach, Laura Henao Caviedes, Consolato M. Sergi
Journal: Liver Cancer (2021)

Hepatocellular carcinoma is one of the most common causes of cancer-related death worldwide. In cases of liver resection for hepatocellular carcinoma, the dissector, whether a pathologist's assistant, physician, or resident, must have a clear understanding of both the terminology of liver anatomy and the requirements of the corresponding College of American Pathologists Cancer Protocol to properly orient, describe, dissect, and sample the specimen. This chapter provides guidance for the gross dissection procedure for the production of a valuable pathology report, which is of key importance for a patients' ongoing care.
Circadian variation in the frequency of sudden cardiac death.
Authors: J EMuller, P LLudmer, S NWillich, G HTofler, GAylmer, IKlangos, P HStone
Journal: Circulation (1987)

To determine whether sudden cardiac death exhibits a circadian rhythm similar to that recently demonstrated for nonfatal myocardial infarction, we analyzed the time of day of sudden cardiac death as indicated by death certificates of 2203 individuals dying out of the hospital in Massachusetts in 1983. The data reveal a prominent circadian variation of sudden cardiac death, with a low incidence during the night and an increased incidence from 7 to 11 A.M. The pattern is remarkably similar to that reported for nonfatal myocardial infarction and episodes of myocardial ischemia. The finding that the frequency of sudden cardiac death is increased in the morning is compatible with hypotheses that sudden cardiac death results from ischemia or from a primary arrhythmic event. Further study of the physiologic changes occurring in the morning may provide new information supporting or refuting these hypotheses, thereby leading to increased understanding and possible prevention of sudden cardiac death.
Relationship between blood flow direction and endothelial cell orientation at arterial branch sites in rabbits and mice.
Authors: B LLangille, S LAdamson
Journal: Circulation Research (1981)

The orientation of endothelial cells near arterial branch sites has been compared with flow streamlines near the arterial wall. We detected cell orientation by examining cell impressions in vascular casts of rabbit and mouse arterial branch sites. Flow streamlines were assessed in glass models with flow parameters approximating mean in vivo values. At high Reynolds numbers (large arteries), secondary flow develop near branch sites, and this was reflected in the pattern of streamlines near the vessel wall. At symmetrical Y bifurcations, streamlines originating near the inner wall of the branches are directed toward the lateral wall; thus they appear to wind around the daughter vessels and merge on the lateral wall. A similar phenomenon was observed on a 90 degree side branch. When flow conditions in the Y bifurcation and side branch models approximated those at the iliac bifurcation and renal artery origin, respectively, the streamlines near the walls were almost identical to the patterns of endothelial ce...
Inappropriate Data and Measures Lead to Questionable Conclusions
Authors: Glen I. Spielmans, Jon Jureidini, David Healy, Robert Purssey
Journal: JAMA Psychiatry (2013)

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 Psychiatry 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 Psychiatry journal
Effects of aspirin and prostaglandin E1 on in vitro thrombolysis with urokinase. Evidence for a possible role of inhibiting platelet activity in thrombolysis.
Authors: WTerres, CBeythien, WKupper, WBleifeld
Journal: Circulation (1989)

The formation of thrombi in vivo includes the activation of both platelets and the coagulation cascade. Conventional thrombolytic therapy is primarily directed toward the dissolution of fibrin. To evaluate the possibility that platelet activity impairs the lysis of thrombi, we studied the effects of aspirin and platelet-deaggregating prostaglandin E1 on thrombolysis with urokinase. Combined platelet and fibrin thrombi were produced in vitro by adding CaCl2 and collagen (1 microgram/ml) to citrated platelet-rich plasma (250,000 platelets per microliters). Urokinase (500-10,000 units/ml) caused a dose-dependent weight loss of the thrombi that was maximal at 2,000 units/ml. The addition of aspirin (10-200 micrograms/ml) to platelet-rich plasma before thrombus formation markedly enhanced thrombolysis with urokinase. This effect was most pronounced at 20 micrograms/ml aspirin. However, when aspirin was added after completion of thrombus formation, no significant effect on thrombolysis was noted. Prostaglandin ...
The Biological Exposure Indices: A Key Component in Protecting Workers from Toxic Chemicals
Authors: Michael S. Morgan
Journal: Environmental Health Perspectives (1997)

Abstract
Biological monitoring of exposure to chemicals in the workplace is an important component of exposure assessment and prevention of adverse health effects. It should be employed in conjunction with ambient air monitoring to provide information on the absorbed dose of a chemical agent and the effect of all routes of exposure. Judgments regarding the acceptable level of a chemical or its metabolite in biological samples are facilitated by comparison to a reference value. The American Conference of Governmental Industrial Hygienists has established a series of recommended reference values called the Biological Exposure Indices (BEI). The history and characteristics of the BEI are reviewed, and their suitability for use by occupational health specialists is examined. A number of challenges and stimuli to the continued development and improvement of these reference values are described, and the impact of recent advances in macromolecular biology is assessed.
Frequency-dependent effects of quinidine on the ventricular action potential and QRS duration in humans.
Authors: KNademanee, W GStevenson, J NWeiss, V BFrame, M GAntimisiaris, TSuithichaiyakul, C MPruitt
Journal: Circulation (1990)

We studied the frequency-dependent effects of quinidine on the right ventricular action potential and QRS duration in 10 patients (nine men and one woman; mean age, 57 +/- 14 years) undergoing electrophysiologic studies for clinical indications. The right ventricular monophasic action potential, electrocardiographic, and conventional intracardiac electrical signals from various sites were recorded at different pacing cycle lengths from 30 seconds to 1 minute before and after a 10-mg/kg i.v. quinidine infusion. We used the extrastimulus technique to determine the effects of quinidine on ventricular refractory periods at different pacing cycle lengths and on the abrupt changes of the action potential duration. The action potential duration progressively decreased as the ventricular pacing rate increased at baseline and after quinidine infusion. Quinidine significantly increased the action potential duration from that of control by 25 msec (p less than 0.02) at the relatively slow pacing cycle lengths of 600...
Development of short-term myocardial hibernation. Its limitation by the severity of ischemia and inotropic stimulation.
Authors: RSchulz, JRose, CMartin, O EBrodde, GHeusch
Journal: Circulation (1993)

BACKGROUNDShort-term hibernating myocardium is characterized by a decrease in contractile function in proportion to the reduced myocardial blood flow. Myocardial creatine phosphate content, initially decreased during the first minutes of ischemia, returns to near-control values, the ischemia-induced net lactate production is attenuated, and the myocardium remains viable despite ongoing hypoperfusion and contractile dysfunction. Hibernating myocardium after 85 minutes of ischemia maintains an inotropic reserve and responds to short-term intracoronary dobutamine infusion with increased work; however, this inotropic response is at the expense of metabolic recovery. We therefore hypothesized that the development of myocardial hibernation is a delicate process that is easily disturbed by unfavorable alterations in the oxygen-supply demand balance.METHODS AND RESULTSTo study the impact of prolonged inotropic stimulation on the development of myocardial hibernation, the left anterior descending coronary artery w...
Loss of the improvement of angina between 1 and 7 years after aortocoronary bypass surgery: correlations with changes in vein grafts and in coronary arteries.
Authors: LCampeau, JLespérance, JHermann, FCorbara, C MGrondin, M GBourassa
Journal: Circulation (1979)

Improvement of effort angina following pure aortocoronary bypass graft surgery was related to postoperative control angiographic studies of grafts and coronary arteries in 75 unselected patients. Clinical and angiographic evaluations were carried out at approximately 1 year and at 5 to 7 years after surgery. At 1 year, 61 (81.3%) were improved (52 without angina and 9 with partial improvement by at least two functional classes), whereas 14 were unimproved (18.7%). At approximately 6 years, loss of improvement (reappearance of angina or aggravation by at least two functional classes) was observed in 22 of the 61 improved patients, representing an attrition of 36.1% over a 5-year period. Graft occlusion or a narrowing of over 50% was observed in two of the 39 patients in whom improvement had continued (5.1%), whereas it was found in six of the 22 patients (27.3%) whose results deteriorated (p less than 0.05). Similarly, progression to occlusion of a preexisting stenosis of over 50% or appearance of a new st...
Spectral characteristics of heart rate variability before and during postural tilt. Relations to aging and risk of syncope.
Authors: L ALipsitz, JMietus, G BMoody, A LGoldberger
Journal: Circulation (1990)

Fourier analysis of heart rate (HR) may be used to characterize overall HR variability as well as low- and high-frequency components attributable to sympathetic and vagal influences, respectively. We analyzed HR spectral characteristics of 12 healthy young (18-35 years) and 10 healthy old (71-94 years) subjects before and during 60 degrees head-up tilt. Total spectral power in the 0.01-0.40-Hz frequency range and low-frequency (0.06-0.10 Hz) and high-frequency (0.15-0.40 Hz) components of the HR power spectrum were significantly lower in old than in young subjects in supine and upright positions. To characterize and compare overall HR variability in young and old subjects, we computed the regression lines relating the log amplitude to the log frequency of the supine HR spectra (l/fx plots). The regression lines for old subjects were lower and steeper (mean slope, -0.78 [5%, 95% confidence limits (CL), -0.73, -0.83]) than in young (mean slope, -0.67 [CL, -0.62, -0.72]), indicating not only reduced overall ...