tbuckley/cabot-search huggingface dataset:
Antiarrhythmic actions of diltiazem during experimental atrioventricular reentrant tachycardias. Importance of use-dependent calcium channel-blocking properties.
Authors: MTalajic, DPapadatos, CVillemaire, MNayebpour, SNattel
Journal: Circulation (1990)

The purpose of this study was to determine if the known frequency-dependent effects of diltiazem on inward calcium current result in selective actions during supraventricular tachycardia. These effects were evaluated by use of an experimental model of orthodromic atrioventricular reentrant tachycardia (AVRT). AVRT was induced in 15 dogs over a wide range of retrograde conduction times before and after two doses of diltiazem. Diltiazem produced a tachycardia-related suppression of atrioventricular nodal conduction resulting in greater efficacy for faster than for slower AVRTs. The degree of slowing for tachycardias that remained inducible after diltiazem administration was greater for AVRTs with a rapid initial rate (dose 1, 29%; dose 2, 40%) than for slower AVRTs (dose 1, 11%, p less than 0.01; dose 2, 18%, p less than 0.001). Rate-dependent AVRT slowing occurred because of a time-dependent phase of AH interval prolongation after the onset of tachycardia, which was observed only after diltiazem administra...
Noninvasive assessment of cardiomyopathy development with simultaneous measurement of topical 1H- and 31P-magnetic resonance spectroscopy.
Authors: TToyo-oka, KNagayama, JSuzuki, TSugimoto
Journal: Circulation (1992)

Background. It might be possible to estimate the metabolic derangement of cardiac muscle by topical nuclear magnetic resonance spectroscopy (MRS) in vivo without killing the animal. Methods and Results. By use of topical 1H- and 31P-MRS focused on the heart of Syrian hamsters with or without cardiomyopathy (CM; BIO 14.6 strain), the chemical constituents were measured in vivo nondestructively and repetitively at several stages of development of CM. A phantom experiment and two-dimensional plot of chain methylenes (CH2) of lipid/water ratio by 1H-MRS versus creatine phosphate (CP)/[beta-P]ATP ratio by 31P-MRS indicated that signal cross talk from the adjacent organs was negligible. Even before the onset of clinical or pathological manifestation of CM (7 weeks after birth), CH2/water ratio by 1H-MRS was lower in the CM group (7.3 +/- 0.7%) than in control (11.8 +/- 2.0%, p less than 0.05), and it decreased further at the hypertrophic stage (17 weeks, 4.1 +/- 0.7%, p less than 0.05) and the congestive stage ...
KISS1 suppresses melanoma metastases to multiple organs
Authors: Kevin T. Nash, Pushkar A. Phadke, John F. Harms, John C. Kappes, Yujiang Jia, Danny R. Welch
Journal: Cancer Research (2006)

4308  The KISS1 metastasis suppressor has been shown to be a potent inhibitor of pulmonary metastases. However, its value as a potential clinical target for the management of metastatic disease would be greater if metastases to other organs could be inhibited as well. We tested the hypothesis that KISS1 can inhibit metastases to multiple organs by using an intracardiac injection model. C8161.9, a highly metastatic human melanoma cell line, was transduced with green fluorescent protein (GFP) to quantify metastatic foci in whole organs. C8161.9 GFP cells were subsequently transfected with pcDNA3 vector or pcDNA3-KISS1 and stable clones were isolated. 2×105 cells comprised of parent, vector, or three KISS1 stables clones were injected into the left ventricle of athymic mice. Five weeks later, whole organs were removed and all metastatic foci were imaged and counted using a stereomicroscope. The incidence of skeletal metastases was reduced from 100% in parent and vector controls to 10–33% by the KISS1-expressing clones (p
A possible change in the rate-limiting step for cardiac norepinephrine synthesis in the cardiomyopathic Syrian hamster.
Authors: M JSole, A BKamble, M NHussain
Journal: Circulation Research (1977)

The development of heart failure in the cardiomyopathic hamster is associated with a decrease in norepinephrine stores and parallel increases in cardiac sympathetic tone and tyrosine hydroxylase activity. Despite the increase in tyrosine hydroxylase, cardiac norepinephrine synthesis does not increase in heart failure. In this study, we have shown that an accumulation of cardiac dopamine accompanies the decline of cardiac norepinephrine. The abnormal content of norepinephrine and of dopamine in the decompensating hamster heart is restored to normal by peripheral ganglionic blockade. The acute increase in cardiac sympathetic tone induced by immobilization stress in control hamsters mimics the alterations in cardiac catecholamine distribution found in heart failure. Other investigators have demonstrated similar alterations in the catecholamine content of the rat submaxillary gland and adrenal medulla following an increase in sympathetic input to these organs. We conclude that the increase in cardiac sympathe...
Tetralogy of Fallot: an angiographic-pathologic correlative study.
Authors: BSoto, A DPacifico, RCeballos, L MBargeron
Journal: Circulation (1981)

The anatomic abnormalities observed by cineangiographic axial techniques of 12 patients with tetralogy of Fallot were correlated with anatomic details noted at necropsy. Right ventricular angiograms made in the right anterior oblique view best demonstrated the severity and type of infundibular obstruction and also permitted differentiation of the perimembranous, infundibular muscular and subarterial types of ventricular septal defects. The degree of aortic overriding was best displayed in the long-axis view. Comparison of the intracardiac anatomy of each postmortem specimen with the respective premortem cineangiogram has provided further clarification of the angiographic anatomy displayed by these axial techniques.
Kinetics of myoglobin release and prediction of myocardial myoglobin depletion after coronary artery reperfusion.
Authors: A KEllis, B RSaran
Journal: Circulation (1989)

To better define the usefulness of blood myoglobin measurements in evaluating the effectiveness of attempted thrombolysis, we studied the kinetics of myoglobin entry into and removal from the circulation after coronary artery reperfusion and the relation between directly measured depletion of myocardial myoglobin after coronary occlusion and reperfusion and the amount of depletion predicted from plasma myoglobin concentration-time curves. Initially, canine myoglobin was administered to 11 dogs by both bolus injection and 40-minute infusion, and the subsequent disappearance patterns of myoglobin from plasma monitored by radioimmunoassay. A monoexponential regression line (corresponding to a one-compartment model) and a biexponential regression line (corresponding to a two-compartment model) were determined for each set of washout data, the kinetic parameters were calculated, and the goodness of fit of each model was assessed. Results were similar after both methods of myoglobin administration. In five of 1...
Abstract 17502: Using Patient-Centered Outcomes Research Principles to Develop and Implement a Mobile Heart Failure Self-Care Program
Authors: Amber E Johnson, Dennis M McNamara, Ravi Ramani, Christy N Taylor, Esa M Davis
Journal: Circulation (2020)

Introduction: Patients admitted with decompensated heart failure (HF) are at risk for hospital readmission and poor quality of life. Remote monitoring and mobile health (mHealth) technologies can help prevent hospitalization for community-dwelling patients. We aimed to develop a HF mHealth application to enhance self-care after HF hospitalization. Hypothesis: We hypothesized that 1) a mHealth platform could be designed to increase HF self-care after hospital discharge for a population at high risk for HF readmission and 2) our tool would be user friendly and feasibly deployed. Methods: Intervention development included input from the following stakeholders: patients, clinicians, information technology developers, patient education experts, and mHealth researchers. We recruited 32 inpatient adults with HF and randomized them 1:1 to the mHealth program plus usual HF care or usual care only. Patients discharged to a nursing home, with end-stage HF (e.g. awaiting transplant/ventricular assist device or on palliative inotropes), or without a smart phone were excluded. Feasibility was determined by ease of deployment, duration of participant recruitment, and participant attrition. We measured program usability by how often the application was opened and used by patients. Results: We developed an educational HF mHealth patient self-care tool consisting of daily videos and self-assessments. Of 202 patients screened: 13 were excluded due to discharge to nursing home; 28 were excluded for end-stage HF; 9 were excluded because they did not have a smart phone. We enrolled 32 patients, 14 of which were randomized to receive the program. Mean age was 60 years (range 22-85). There were 53% male and 81% White. Four of 14 (28.6%) did not fully complete the 90-day program. All survey respondents expressed satisfaction with the intervention. Conclusions: We conducted a pilot study of a HF self-care mHealth tool for adults at risk for HF readmission and have determined it to be both feasible and acceptable. Our intervention, although a research prototype, may serve as a novel approach to reduce hospital admission and improve patient ability to manage HF as an outpatient.
Determinants of 2-year outcome after coronary angioplasty in patients with multivessel disease on the basis of comprehensive preprocedural evaluation. Implications for patient selection. The Multivessel Angioplasty Prognosis Study Group.
Authors: S GEllis, M JCowley, GDiSciascio, UDeligonul, E JTopol, T MBulle, M GVandormael
Journal: Circulation (1991)

BACKGROUNDTo assess the likelihood of intermediate-term event-free survival (freedom from death, coronary artery bypass surgery, and myocardial infarction) in patients with multivessel coronary disease undergoing coronary angioplasty, 350 consecutive patients from four clinical sites were carefully evaluated and followed for 22 +/- 10 months.METHODS AND RESULTSEight clinical variables were evaluated at the clinical sites, and 23 angiographic variables describing the number, morphology, and topography of coronary stenoses were evaluated at a core angiographic laboratory. Most patients had Canadian Cardiovascular Society class III or IV angina (72%), two-vessel coronary disease (68%), and well-preserved left ventricular function (mean ejection fraction, 58 +/- 12%; range, 18-85%). Follow-up was complete in 99% of patients. At 2 years, event-free survival was 72%, overall survival was 96%, freedom from bypass surgery was 82%, and freedom from nonfatal myocardial infarction without surgery was 96%. Sequential...
Subtypes of beta-adrenergic receptors in bovine coronary arteries.
Authors: D EVatner, D RKnight, C JHomcy, S FVatner, M AYoung
Journal: Circulation Research (1986)

Whether large coronary artery dilation induced by beta-adrenergic stimulation is mediated by beta 1- or beta 2-adrenergic receptors remains controversial. This problem is particularly difficult to address in vivo due to the concomitant increase in coronary blood flow with beta-adrenergic stimulation, which by itself can dilate large coronary arteries. To reconcile this problem, 5 calves were instrumented with intraaortic and intracoronary (i.c.) catheters, ultrasonic diameter transducers, Doppler flow transducers, and hydraulic occluders on the left circumflex coronary artery. Two to six weeks following surgery, beta-adrenergic agonists were administered i.c. to avoid complicating systemic effects. Isoproterenol (0.0025 micrograms/kg, a beta 1 + beta 2-adrenergic agonist) increased coronary diameter (7.1 +/- 0.8% from 5.80 +/- 0.58 mm) (p less than 0.01). Similar increases (p less than 0.01) in coronary diameter occurred with prenalterol (0.4 micrograms/kg, beta 1-adrenergic agonist) (9.5 +/- 1.4%) and pi...
Multicentre Randomised Double-Blind Placebo Controlled Trial of Cytisine for Smoking Cessation in Smokers with Tuberculosis
Authors: Omara Dogar, Ada Keding, Rhian Gabe, Anna-Marie Marshall, Rumana Huque, Deepa Barua, Razia Fatima, Amina Khan, Raana Zahid, Sonia Mansoor, Daniel Kotz, Melanie Boeckmann, Helen Elsey, Eva Kralikova, Steve Parrott, Jinshuo Liu, Anne Readshaw, Aziz Sheikh, Kamran Siddiqi
Journal: The Lancet Global Health (2020)
Casting a Wide Net
Authors: Aviva Cohn, Matthew Nehs, Jennifer Chan, Anand Vaidya
Journal: New England Journal of Medicine (2021)

A 16-year-old girl presented to her pediatrician for evaluation of recent weight gain, irritability, weakness, and skin changes. Her mother reported that her daughter’s grades at school had declined and that she had left the cheerleading team owing to fatigue. In the past 2 years, the patient had gained 23 kg. She was now severely obese and had diabetes. Her general appearance had also changed: her face had become rounded, and acne and hirsutism had developed. She had previously . . .
The Efficacy of Band Ligation for Gastroesophageal Varices 2-3 Sm Distal to Z-Line
Authors: K Manukyan, A Khalatyan, S Khachatryan
Journal: Endoscopy (2021)

Aims The main accepted methods are band ligation and obliteration with cyanoacrylate glue for gastroesophagel variceal bleeding. The aim of this study to evaluate the efficacy of band ligation for varices 2-3 sm distal to Z -line.
Cardiac sarcoid: a clinicopathologic study of 84 unselected patients with systemic sarcoidosis.
Authors: K JSilverman, G MHutchins, B HBulkley
Journal: Circulation (1978)

Although sarcoid may involve the myocardium, there is little information on its incidence or significance. We studied 84 consecutive autopsied patients with sarcoidosis. The patients ranged in age from 18--80 years (average 46 years) and 61% were women; 23 (27%) of them had myocardial granulomas. In eight (35%) these were clinically silent, and in 15 (65%) there was a history of heart failure and/or arrhythmias and conduction defects. Of the 23 patients, only four (17%) had grossly evident, widespread myocardial lesions: three of these four (75%) had documented arrhythmias. All four had sudden, unexpected death at an average age of 36 years; in only two had sarcoid been suspected during life. The other 19 patients (83%) had microscopically evident granulomatous involvement. Of these, eight (42%) had a thythm or conduction disturbance and three (16%) sudden death, although none of those who suffered sudden death had a recognized rhythm or conduction disturbance. Nine (15%) of those without cardiac sarcoido...
Electrocautery-Enhanced Delivery System of Lumen Apposing Metal Stent for EUS-Guided Biliary and Gallbladder Drainage: A Single-Center Study
Authors: C Robles-Medranda, R Oleas, J Alcivar-Vasquez, Lopez AC, M Sanchez-Carriel, M Puga-Tejada, H Pitanga-Lukashok
Journal: Endoscopy (2021)

Aims We aimed to evaluate the feasibility and safety of lumen-apposing metal stents for EUS-guided biliary and gallbladder drainage.
Use of combined diet and colestipol in long-term (7--7 1/2 years) treatment of patients with type II hyperlipoproteinemia.
Authors: P TKuo, KHayase, J BKostis, A EMoreyra
Journal: Circulation (1979)

Long-term effects of diet and colestipol (a bile acid sequestrant) were studied in 25 patients with familial type II hyperlipoproteinemia. Serum lipids and body weights of an initial group of 30 patients were stabilized by low cholesterol-saturated fat-refined carbohydrate diet and the patients were then randomized into placebo and drug-treatment groups. After explaining that the drug is nontoxic and effective in lowering serum lipids, total cholesterol (C) and low-density lipoprotein cholesterol (LDL-C), colestipol (30 g/day) and diet were given to the 25 patients who remained in the long-term follow-up program. The treatment resulted in highly significant lowering of serum lipids (mg/dl, mean +/- SEM): C and LDL-C from 412.7 +/- 24.4 and 331.1 +/- 22.8 to 270 +/- 11.0 and 188.1 +/- 13.8, respectively (p less than 0.001 in each instance) over 7--7 1/2 years. Although we observed no absolute increase in high density lipoprotein (HDL), the HDL/LDL ratio was elevated. Long-term colestipol and diet treatment...
Inappropriate Use of the Term <i>Autism</i> as Analogy
Authors: Geraldine Dawson
Journal: JAMA Pediatrics (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 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
Impairment of autonomically mediated heart rate control in patients with cardiac dysfunction.
Authors: R EGoldstein, G DBeiser, MStampfer, S EEpstein
Journal: Circulation Research (1975)

Patients with cardiac disorders have defective parasympathetic control of heart rate. To evaluate the possibility of similar changes in sympathetic control of heart rate, we compared reflex chronotropic responses to 80 degree upright tilt and nitroglycerin-induced hypotension in 31 cardiac patients and 7 normal individuals before and after partial parasympathetic blockade with atropine. Tilting revealed an attenuation of the normal heart rate increase in patients; the magnitude of this defect was greatest in patients with more severe symptoms (class III) and evidence of left ventricular dysfunction (the heart rate increase averaged 25 plus or minus 3 beats/min in normal subjects, 12 plus or minus 2 beats/min in class I-II patients, and 7 plus or minus 1 beats/min in class III patients). Class III symptoms due to mechanical causes (mitral stenosis), however, were not associated with this defect. A marked reduction in heart rate rise with hypotension was seen only in those class III patients without mitral ...
Staircase in frog ventricular muscle. Its dependence on membrane excitation and extracellular ionic composition.
Authors: J MChesnais, FKavaler, T WAnderson, ECoraboeuf
Journal: Circulation Research (1978)

Staircase was studied in frog ventricle strip preparations where it was possible to alter extracellular ionic composition extremely rapidly in the diastolic interval between beats. Several findings strongly indicate that staircase in this tissue is a result of progressively increasing calcium influx per beat, rather than a beat-by-beat augmentation of an intracellular calcium pool which contributes to activation. After a steady state of force development, the very next beat could be graded, from approximately zero force to the steady state value attained during the staircase progression, by grading the calcium concentration of a new Ringer's solution switched to perfuse the muscle in the diastolic period immediately before that beat. Also, action potentials, elicited during the quiescent period in the virtual absence of contraction (in 0.025 mm calcium Ringer's solution), markedly increase force development and accelerate the staircase seen upon return to normal Ringer's solution. Staircase is augmented...
Endoscopic Resection Of Colonic Lipomas: A Single Tertiary Centre Experience
Authors: L Chong, S Hebbar
Journal: Endoscopy (2021)

Aims Endoscopic resection of colonic lipomas is warranted if lesions are large (> 2 cms) and symptomatic. We aimed to report the patient characteristics, technical outcomes and clinical improvement in patients who underwent endoscopic resection of colonic lipomas at our tertiary institution.
Periodic procainamide for paroxysmal tachycardia.
Authors: D WBenson, ADunnigan, T PGreen, D GBenditt, S PSchneider
Journal: Circulation (1985)

We evaluated the efficacy of a single oral dose of procainamide to terminate paroxysmal tachycardia, when procainamide was taken shortly after onset of tachycardia, a regimen we have termed periodic procainamide. In 12 patients (mean age 15 years) with non-life-threatening tachycardia (orthodromic reciprocating tachycardia, 8/12; ventricular tachycardia, 3/12; atrial flutter, 1/12) in whom intravenously administered procainamide (15 mg/kg at 1 mg/kg/min) terminated tachycardia, efficacy of a single oral dose of procainamide (25 mg/kg) to terminate tachycardia was tested during electrophysiologic study. After oral administration of procainamide, tachycardia was terminated and could not be reinitiated in 11 of 12 patients (9/12 less than 75 min, 2/12 greater than 120 min after administration). Time of tachycardia termination approximately coincided with the time of peak serum concentration of procainamide after the single oral dose. Delayed response or failure of procainamide to terminate tachycardia was ...
Diagnostic value of QRST isointegral maps in detecting myocardial infarction complicated by bundle branch block.
Authors: HHayashi, SWatabe, SYabe, KTakami, SOhsugi, MHirai, MMizutani, HSaito
Journal: Circulation (1989)

The clinical usefulness of QRST isointegral maps (IQRST map) for detecting myocardial infarction that was complicated by intraventricular conduction disturbances was evaluated in patients with right bundle branch block (group RBBB, 64 patients) and left bundle branch block (group LBBB, 40 patients) by comparison with the normal mean IQRST map derived from 50 normal subjects. Myocardial infarction complicated the conduction disturbances in 24 of the 64 RBBB and in 18 of the 40 LBBB patients. A correlation coefficient was used for assessing the similarity of each map pattern with the normal mean IQRST map. The difference map was made by subtracting the average normal IQRST map from each abnormal IQRST map, and those differences that were less than 2 SD from the mean were retained as a significant area. The number of leads and their sum of differences were used to represent the size of the difference map. Correlation coefficients were significantly (p less than 0.001) smaller in patients with bundle branch b...
Angiotensin degradation products mediate endothelium-dependent dilation of rabbit brain arterioles.
Authors: R LHaberl, P JDecker, K MEinhäupl
Journal: Circulation Research (1991)

This study demonstrates that the hexapeptide angiotensin II-(3-8) and L-arginine, generated through enzymatic degradation of angiotensin, mediate endothelium-dependent dilation in rabbit brain arterioles. Topical application of angiotensin II (10(-5) M) on the brain surface of anesthetized rabbits caused 21.6 +/- 4.5% (mean +/- SEM) cerebral arteriolar dilation. The cyclooxygenase inhibitor indomethacin did not change this dilation. The natural degradation product of angiotensin II in the brain, angiotensin III, also induced vasodilation at concentrations of 10(-7) to 10(-5) M. The dilation to angiotensin II and angiotensin III was eliminated in the presence of 10(-5) M methylene blue, a known inhibitor of endothelium-dependent vasodilation. Amastatin, an aminopeptidase inhibitor and blocker of enzymatic angiotensin degradation, also inhibited the response to angiotensin II and angiotensin III. The angiotensin fragment angiotensin II-(3-8), which lacks the amino-terminal L-arginine residue of angiotensin ...