tbuckley/cabot-search huggingface dataset:
Paroxysmal hypotension associated with sympathetic withdrawal. A new disorder of autonomic vasomotor regulation.
Authors: R SWilliams, T MBashore
Journal: Circulation (1980)

We evaluated a patient who had transient episodes of hypotension with clinical and laboratory features apparently distinct from previously recognized disorders of vasomotor regulation. In between his abrupt attacks of hypotension, the patient is asymptomatic and demonstrates normal autonomic modulation of heart rate and blood pressure in response to changes in body position, Valsalva maneuver, cold, and exercise. During periods of hypotension, his plasma norepinephrine falls markedly and he has blunted or absent responses to stimuli that normally have a pressor effect due to sympathetic efferent discharge. Mechanical or known hormonal disorders that produce episodic hypotension have been excluded by extensive testing. We suggest two possible causes for our patient's paroxysmal sympathetic withdrawal: first, a centrally mediated inhibition of sympathetic discharge to peripheral resistance and capacitance vessels, but with no afferent stimulus reflexly producing sympathetic withdrawal readily evident; or se...
Random exercise stress test in diagnosing effort angina.
Authors: ASuyama, KSunagawa, KHayashida, MSugimachi, KTodaka, YNose, MNakamura
Journal: Circulation (1988)

To improve the performance of exercise stress testing in the diagnosis of effort angina while minimizing risks of serious complications, we evaluated an impulse response of ST changes, which is a transient ST response resulting from a hypothetical, strenuous-impulselike exercise, without actually imposing the strenuous load. To obtain the impulse response, subjects walked intermittently according to a computer-generated random binary sequence on a treadmill for 20 minutes (with a constant speed of 1.7 mph and a slope of 10%). We used Fourier transform for beat-to-beat changes in ST level and the binary sequence of exercise. We then determined the transfer function by taking the ratio of Fourier transformed ST level to exercise over the frequency range of 0.5 through 5.0 cycles/min. Converting the transfer function to the time domain yielded the impulse response of ST change. The subjects consisted of 49 patients (60 +/- 9 years) with effort angina, 13 patients with atypical chest pain (56 +/- 9 years), an...
The new (Version 9) American Joint Committee on Cancer tumor, node, metastasis staging for cervical cancer
Authors: Alexander B. Olawaiye, Thomas P. Baker, M. Kay Washington, David G. Mutch
Journal: CA A Cancer Journal for Clinicians (2021)

Abstract The American Joint Committee on Cancer (AJCC) tumor, node, metastasis (TNM) staging for all cancer sites has been periodically updated as a published manual for many years. The last update, the eighth edition AJCC Cancer Staging Manual went into use on January 1, 2018. The AJCC has since restructured and updated its processes, and all AJCC staging‐related data are now housed on its new application programming interface. Consequently, the next AJCC TNM staging update, AJCC version 9 TNM staging, will be published electronically and will be released chapter by chapter. The first chapter of version 9 AJCC TNM staging is the updated cervical cancer staging, which is now published. This article highlights the changes to the AJCC TNM cervical cancer staging; these changes align with the International Federation of Gynecology and Obstetrics staging. The most important of the changes are: 1) the incorporation of imaging and surgical findings, 2) the elimination of lateral spread from T1a, 3) the addition of a subcategory to T1b (T1b3), and 4) histopathology is updated to reflect human papillomavirus‐associated and human papillomavirus‐independent carcinomas.
Mechanoenergetic effects of pimobendan in canine left ventricles. Comparison with dobutamine.
Authors: KHata, YGoto, SFutaki, YOhgoshi, HYaku, OKawaguchi, TTakasago, ASaeki, T WTaylor, TNishioka
Journal: Circulation (1992)

BACKGROUNDWe hypothesized that the effect of pimobendan (UD-CG 115 BS) to increase calcium sensitivity of contractile protein might result in less myocardial oxygen consumption (VO2) in comparison with dobutamine when they enhance ventricular contractility to the same extent. To examine this hypothesis, we compared the effects of pimobendan and dobutamine on left ventricular contractility and energetics using the frameworks of Emax (contractility index) and the relation between VO2 and PVA (systolic pressure-volume area, a measure of left ventricular total mechanical energy).METHODS AND RESULTSWe measured VO2, Emax, PVA, and force-time integral (FTI) in excised, cross-circulated, nonfailing dog hearts. The slope of the VO2-PVA relation reciprocally indicates the efficiency from PVA-dependent VO2 to the total mechanical energy (contractile efficiency). The VO2 intercept of the VO2-PVA relation, i.e., PVA-independent VO2, reflects energy utilization for excitation-contraction coupling. The ratio of FTI to P...
Prevention of reoccluding platelet-rich thrombi in canine femoral arteries with a novel peptide antagonist of platelet glycoprotein IIb/IIIa receptors.
Authors: E JHaskel, S PAdams, L PFeigen, J ESaffitz, R JGorczynski, B ESobel, D RAbendschein
Journal: Circulation (1989)

The composition of an evolving arterial thrombus may be a determinant of how effectively pharmacologic agents prevent reocclusion after initially successful thrombolysis. In this study, reoccluding platelet- or fibrin-rich thrombi as delineated by scanning electron microscopy were produced selectively in the femoral arteries of dogs with the use of electrically induced vascular injury or implantation of copper wire, respectively. Initial thrombolysis after intravenous infusion of tissue-type plasminogen activator (1 mg/kg over 30 minutes) was less frequent in the preparation producing platelet-rich thrombi than in that producing fibrin-rich thrombi (lysis in 19 of 24 versus 18 of 18, p = 0.06). In dogs with initial arterial recanalization, intravenous infusion of arginine-glycine-aspartate-O-methyltyrosine amide (RGDY), which competes with fibrinogen for binding to platelet glycoprotein IIb/IIIa receptors, prevented reocclusion caused by recurrence of platelet-rich thrombi in six of six dogs within 90 min...
Intraoperative Ventilation Strategies to Reduce Pulmonary Complications in Obese Patients
Authors: Carlos Ferrando, Gerardo Tusman, Fernando Suarez-Sipmann
Journal: JAMA (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 HomeNew OnlineCurrent IssueFor Authors 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) Podcasts Clinical Reviews Editors' Summary Medical News Author Interviews More 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 journal
Left ventricular volume from paired biplane two-dimensional echocardiography.
Authors: N BSchiller, HAcquatella, T APorts, DDrew, JGoerke, HRingertz, N HSilverman, BBrundage, E HBotvinick, RBoswell, ECarlsson, W WParmley
Journal: Circulation (1979)

To evaluate the applicability of two-dimensional echocardiography to left ventricular volume determination, 30 consecutive patients undergoing biplane left ventricular cineangiography were studied with a wide-angle (84 degrees), phased-array, two-dimensional echocardiographic system. Two echographic projections were used to obtain paired, biplane, tomographic images of the left ventricle. We used the short-axis view (from the precordial window) as an anolog of the left anterior oblique angiogram, and the long-axis, two-chamber view (from the apex impulse window) as a right anterior oblique angiographic equivalent. A modified Simpson's rule formula was used to calculate systolic and diastolic left ventricular volumes from the biplane echogram and the biplane angiogram. These methods correlated well for ejection fraction (r = 0.87) and systolic volume (r = 0.90), but only modestly for diastolic volume (r = 0.80). These correlations are noteworthy because 65% of the patients had significant segmental wall mo...
Fibrinopeptide A: a marker of acute coronary thrombosis.
Authors: P REisenberg, L ASherman, KSchectman, JPerez, B ESobel, A SJaffe
Journal: Circulation (1985)

To determine whether coronary thrombosis in vivo is reflected by elevations in levels of fibrinopeptide A (FPA) in plasma, we sequentially characterized plasma FPA levels associated with evolving infarction in patients admitted to the cardiac care unit early after the onset of symptoms, in patients with transmural infarction admitted later, and in patients with nontransmural infarction. Studies were also performed in patients in whom the diagnosis of infarction was suspected but subsequently excluded. FPA values were significantly higher in patients with transmural infarction (42.3 +/- 11.2 ng/ml [mean +/- SEM], n = 53) compared with those in patients with nontransmural infarction (4.8 +/- 1.6 ng/ml, n = 17) or with those in patients in whom infarction was subsequently excluded as a diagnosis (3.5 +/- 0.6 ng/ml, n = 17, p less than .01 for both). Elevations in FPA level were greatest in patients with transmural infarction from whom samples were obtained soon after the onset of symptoms. Thus, in 39 patien...
Assessment of the beta-adrenergic receptor pathway in the intact failing human heart: progressive receptor down-regulation and subsensitivity to agonist response.
Authors: M BFowler, J ALaser, G LHopkins, WMinobe, M RBristow
Journal: Circulation (1986)

We developed methods for identifying beta-adrenergic receptors in human right ventricular endomyocardial biopsy tissue with the radioligand (-)[125I]iodocyanopindolol (ICYP). Specific ICYP binding in a crude, high-yield membrane preparation derived from endomyocardial biopsy tissue was high (specificity greater than 90%), of high affinity (KD around 20 pM), saturable and stereospecific for the (-) vs the (+) isomer of isoproterenol. Subjects with mild-moderate and severe biventricular dysfunction had respective decreases in beta-adrenergic receptor density of 38.2% and 57.7% when normalization methods were averaged, with no significant differences in ICYP dissociation constant. A subgroup of subjects was subdivided by left ventricular ejection fraction (LVEF) into those with mild cardiac dysfunction (LVEF less than 0.50 greater than 0.40) and severe heart failure (LVEF less than 0.20) and given graded sequential infusions of dobutamine and calcium gluconate. Those with severe cardiac dysfunction had marke...
Alpha-adrenoceptor stimulation with exogenous norepinephrine or release of endogenous catecholamines mimics ischemic preconditioning.
Authors: ZBankwala, S LHale, R AKloner
Journal: Circulation (1994)

BACKGROUNDBrief episodes of ischemia induced by proximal coronary artery occlusion can precondition the myocardium. Whether other stressful stimuli have the potential to protect the myocardium from subsequent ischemia remains controversial.METHODS AND RESULTSTo study the hypothesis that transient alpha-adrenoceptor stimulation mimics preconditioning, for 5 minutes we administered 0.25 micrograms.kg-1.min-1 norepinephrine or saline 10 minutes before a 30-minute coronary occlusion and 4 hours of reperfusion in an in vivo rabbit model. The area of necrosis (AN) and area of risk (AR) were measured. We found that norepinephrine pretreatment caused a reduction in infarct size when compared with controls (AN/AR, 0.17 +/- 0.04 versus 0.31 +/- 0.04; P < .02). Ischemic preconditioning also reduced infarct size (AN/AR, 0.22 +/- 0.03). The protection observed with norepinephrine treatment was entirely eliminated by pretreatment with alpha-adrenergic blockade using prazosin (AN/AR, 0.42 +/- 0.06). Tyramine, an agent t...
Antiarrhythmic efficacy of encainide in patients with refractory recurrent ventricular tachycardia.
Authors: J WMason, F APeters
Journal: Circulation (1981)

Encainide is a new agent for treating ventricular arrhythmias. We attempted long-term oral therapy with encainide in 38 patients with recurrent, strikingly drug-refractory ventricular tachycardia. The usual daily dose of encainide ws 150-250 mg divided into four or six doses. The mean period until withdrawal of encainide or the date of follow-up was 4.2 months. Encainide completely eliminated recurrence of ventricular tachycardia in 54% of the patients for 6 months of therapy and in 29% of the patients for 18-30 months of therapy. Twelve patients (32%) had side effects possibly due to encainide; in four, the arrhythmia may have been worsened by encainide. During chronic therapy, encainide increased the PR interval by 18% and the QRS duration by 32%. There was no significant change in the corrected QT interval. The presence of QRS prolongation appeared to correlate with antiarrhythmic effect. We conclude that encainide is a safe, well-tolerated antiarrhythmic agent that is often effective against previousl...
Global Differences in Burden and Treatment of Ischemic Heart Disease in Acute Heart Failure
Authors: Jasper Tromp, Wouter Ouwerkerk, John G.F. Cleland, Christiane E. Angermann, Ulf Dahlstrom, Katherine Tiew-Hwa Teng, Sahiddah Bamadhaj, Georg Ertl, Mahmoud Hassanein, Sergio V. Perrone, Mathieu Ghadanfar, Anja Schweizer, Achim Obergfell, Gerasimos Filippatos, Sean P. Collins, Carolyn S.P. Lam, Kenneth Dickstein
Journal: JACC Heart Failure (2021)
Diagnostic Yield Of Probe-Based Confocal Laser Endomicroscopy (PCLE) In Biliary Stricture Of Undefined Origin
Authors: F Rizzi, M Bruno, M Sacco, S Rizza, M Gesualdo, F Cravero, F Fimiano, F Castellano, A Mauriello, CG De Angelis
Journal: Endoscopy (2021)

Aims Biliary strictures often represent a diagnostic challenge. Their nature can be investigated with trans-papillary brushing and biopsies, cholangiography, cholangioscopy-guided biopsies, EUS-FNA and intraductal ultrasound (IDUS) but none of these thecniques has an optimal diagnostic yield. Probe-based Confocal Laser Endomicroscopy (pCLE) is a promising tool in this setting. Our aim was to evaluate the diagnostic value of pCLE in detecting malignant biliary strictures.
Smooth muscle tone and rapid resetting of rat aortic baroreceptors.
Authors: M CAndresen, MYang
Journal: Circulation Research (1992)

Changes in conditioning mean arterial pressure (cMAP) selectively alter the set point of arterial baroreceptors and baroreflexes without affecting gain. Changes in smooth muscle tone at constant cMAPs shift the pressure-discharge curves of aortic baroreceptors in a similar manner. Using an in vitro preparation of the rat aortic arch, we tested whether near maximal changes in smooth muscle tone affect rapid resetting in single regularly discharging aortic baroreceptors. Discharge, pressure, and aortic diameter were simultaneously measured. By using vasoactive drugs (phenylephrine, angiotensin II, Bay K 8644, and nitroprusside), rapid resetting to cMAP changes was tested during different smooth muscle tone conditions (control, constricted, and dilated). Baroreceptor discharge-response curves were periodically assessed with slow ramps of increasing pressure at each of three different cMAP levels (10-15 minutes each). Rapid resetting relations were constructed for pressure threshold (Pth) and diameter thresho...
It Is Too Early to Declare Early or Late Rescue High-Frequency Oscillatory Ventilation Dead
Authors: Peter C. Rimensberger, Thomas E. Bachman
Journal: JAMA Pediatrics (2014)

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 Pediatrics 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 Pediatrics journal
The effects of ryanodine on calcium-overloaded sheep cardiac Purkinje fibers.
Authors: MValdeolmillos, D AEisner
Journal: Circulation Research (1985)

Prolonged exposure to high concentrations of strophanthidin produces an initial increase followed by a subsequent decrease of twitch tension. The slow decrease is termed calcium overload. The aim of the present work was to investigate the effects of ryanodine (an inhibitor of calcium release from the sarcoplasmic reticulum) on calcium-overloaded sheep cardiac Purkinje fibers. The fibers were voltage-clamped, and tension was measured while monitoring the intracellular calcium concentration with the photoprotein aequorin. When strophanthidin (10 microM) was applied to produce calcium overload, a depolarizing pulse produced twitch, and tonic components of tension and repolarization produced an aftercontraction. These components of tension were accompanied by corresponding increases of aequorin light. Ryanodine (1 microM) gave a transient increase of twitch tension. The twitch then decreased to very low levels. The aftercontraction and its corresponding aequorin light signal decreased monotonically on applica...
Endothelium-dependent modulation of cGMP levels and intrinsic smooth muscle tone in isolated bovine intrapulmonary artery and vein.
Authors: L JIgnarro, R EByrns, K SWood
Journal: Circulation Research (1987)

The role of the endothelium in modulating cyclic nucleotide levels and intrinsic smooth muscle tone was studied in isolated rings of bovine intrapulmonary artery and vein. Cyclic 3',5'-guanosine monophosphate (cGMP) levels were threefold to fourfold higher in unrubbed artery and vein than in vessels that had been denuded of endothelium. Cyclic 3',5'-adenosine monophosphate (cAMP) levels were twofold higher in unrubbed than in endothelium-denuded artery, but no differences were observed in veins. Methylene blue, an inhibitor of guanylate cyclase, decreased cGMP but not cAMP levels, and this was accompanied by increases in smooth muscle tone. M&B 22,948, an inhibitor of cGMP-phosphodiesterase, increased cGMP but not cAMP levels, and this was accompanied by decreases in smooth muscle tone. Unrubbed vessels were more sensitive than endothelium-denuded vessels to the actions of both methylene blue and M&B 22,948, and this may be attributed to endothelium-dependent increases in cGMP turnover. Moreover, unrubbed...
Spinal Epidural Abscess
Authors: Ann S. Baker, Robert G. Ojemann, Morton N. Swartz, Edward P. Richardson
Journal: New England Journal of Medicine (1975)

Thirty-nine patients with spinal epidural abscess were evaluated at the Massachusetts General Hospital between 1947 and 1974. Twenty had acute symptoms, and purulent epidural collections were present; 19 had prolonged courses, and epidural granulation tissue was observed at operation. Staphylococcus aureuswas the most common etiologic agent (57 per cent), followed by streptococci (18 per cent) and gram-negative bacilli (13 per cent). The source of infection was osteomyelitis in 38 per cent of cases and bacteremia in 26 per cent. In 16 per cent epidural abscess was due to postoperative infection. The progression from spinal ache to root pain to weakness followed by paralysis continues to be characteristic of spinal epidural abscess. Although the disease is uncommon, the complications are so serious that prompt diagnosis and treatment are of paramount importance. The combination of back pain with fever and local tenderness is an indication for cerebrospinal-fluid examination and, depending on the results, immediate performance of myelography. (N Engl J Med 293:463–468, 1975)
Changes after quitting cigarette smoking.
Authors: G DFriedman, A BSiegelaub
Journal: Circulation (1980)

Changes in cardiorespiratory symptoms and coronary disease risk indicators over an average 1 1/2-year period were assessed in 9392 persistent cigarette smokers and 3825 persons who quit smoking between two multiphasic checkups. The prevalence of questionnaire-reported chronic cough fell markedly in subjects who quit a one-or-more-pack/day habit (e.g., from 11.2% to 1.8% in white men, p less than 0.001). However, chest pain, shortness of breath and exertional leg pain showed no consistent improvement in quitters compared with persistent smokers. Weight gain was about 2-3 lbs greater in quitters, but changes in blood pressure were small and not consistent across race-sex groups, nor were there consistent differences between persistent smokers and quitters in trends in trends in vital capacity, cholesterol or prevalence of ECG abnormality. Quitting was associated with increase in serum uric acid levels of about 0.2-0.5 mg/dl and relative falls in hemoglobin, leukocyte count and serum glucose levels, all cons...
Pathogenesis of paradoxical hypertension after coarctation resection.
Authors: A PRocchini, ARosenthal, A CBarger, A RCastaneda, A SNadas
Journal: Circulation (1976)

The pathogenesis of paradoxical hypertension after resection of coarctation of the aorta was investigated by comparing the course of seven children undergoing repair of coarctation with five acyanotic children undergoing elective cardiovascular surgery. During the first 24 hours after surgery, all coarctation patients demonstrated a rise in systolic blood pressure (35 +/- 15.5 mm Hg; P less than 0.001), a significant depression in cold pressor test response, and only a slight elevation in plasma renin activity. In the next 24-72 hours, coarctation patients developed a rise in diastolic blood pressure (26.8 +/- 10.6 mm Hg; P less than 0.001), plasma renin activity (22.9 +/- 10.2/ml/hr; P less than 0.001) and fluid retention. By contrast, control patients had no significant postoperative changes. Abdominal pain occurred in five coarctation patients during the period of maximal plasma renin activity. The data suggest that the sympathetic nervous system may be responsible for the initial phase of hypertension...
91P The role of endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA) in the diagnosis of large cell neuroendocrine carcinoma (LCNEC)
Authors: B. Teng, M. Rice, D. Rana, D. Shelton, N. Narine, H.M. Al-Najjar
Journal: Journal of Thoracic Oncology (2021)