tbuckley/cabot-search huggingface dataset:
Syncope associated with supraventricular tachycardia. An expression of tachycardia rate or vasomotor response
Authors: J WLeitch, G JKlein, RYee, R ALeather, Y HKim
Journal: Circulation (1992)

BACKGROUNDSyncope in patients with supraventricular tachycardia has been suggested to be an ominous finding, predictive of rapid rates during tachycardia.METHODS AND RESULTSTo explore the mechanism of syncope during supraventricular tachycardia, tachycardia was induced in the supine position and after passive head-up tilting to 60 degrees in 13 patients with atrioventricular (AV) node reentry, eight patients with AV reentry, and one patient with atrial tachycardia. Tilt testing was also performed in sinus rhythm for 30 minutes (the last 15 minutes with isoproterenol infusion). Mean +/- SEM age was 38 +/- 3 years, and 11 patients had a history of syncope (median number of syncopal episodes, three; range, one to 30). The cycle length of tachycardia when upright was shorter than when supine (297 +/- 9 compared with 357 +/- 10 msec, p less than 0.001), and mean blood pressure fell to a greater extent after the onset of tachycardia (fall in mean blood pressure, 53 +/- 6 compared with 24 +/- 3 mm Hg, p less tha...
Prospective evaluation of dietary and lifestyle pattern indices with risk of colorectal cancer in a cohort of younger women
Authors: Y. Yue, J. Hur, Y. Cao, F.K. Tabung, M. Wang, K. Wu, M. Song, X. Zhang, Y. Liu, J.A. Meyerhardt, K. Ng, S.A. Smith-Warner, W.C. Willett, E. Giovannucci
Journal: Annals of Oncology (2021)
Subaortic fibrous ridge and ventricular septal defect: role of septal malalignment.
Authors: PZielinsky, MRossi, J CHaertel, DVitola, F ALucchese, RRodrigues
Journal: Circulation (1987)

The purpose of this study was to test the hypothesis that the presence of a subaortic ridge associated with a ventricular septal defect (VSD) is related to a malaligned ventricular septum caused by anterior or posterior deviation of the infundibular septum with or without obstructive lesions of the aortic arch. Thirty-two of 295 patients in whom a diagnosis of VSD was made by two-dimensional echocardiography and who were studied from June 1983 to April 1985 presented with a subaortic shelf. Every patient (p less than .00001) had a malalignment type of defect; the defect was produced by anterior deviation of the outlet septum (without compromise of the right ventricular outflow tract) in 28 and by posterior deviation of the infundibular septum in four. The prevalence of a subaortic shelf in the malalignment VSD group was 82% (32/39). Among the 28 patients with a subaortic ridge and anterior deviation of the outlet septum only three had aortic coarctation, but all four patients with subaortic stenosis and p...
Total cholesterol and lipoproteins in school children: prediction of coronary heart disease in adult relatives.
Authors: P PMoll, C FSing, W HWeidman, HGordon, R DEllefson, P AHodgson, B AKottke
Journal: Circulation (1983)

The distribution of risk factors and the prevalence of coronary heart disease (CHD) were studied in 850 first- and second-degree relatives of 98 healthy index cases selected from 3666 school children surveyed for lipid levels in Rochester, Minnesota. Three groups of families were based on an index child's total plasma cholesterol level: 18 families with a child in less than the fifth percentile (low-cholesterol group), 47 with a child in the fifth to ninety-fifth percentiles (middle-cholesterol group) and 33 with a child in greater than the ninety-fifth percentile (high-cholesterol group). The children's cholesterol levels clustered with those of their relatives; mortality due to CHD before age 65 was increased by 2.5 times in grandfathers of index cases in the high-cholesterol group compared with those of the middle-cholesterol group (p less than 0.016). The prevalence of CHD in all the grandfathers was associated with an index child's total cholesterol, more strongly associated with an index child's low...
Primary clinical experience with the Hall-Kaster valve in the aortic position: results at 3 months including hemodynamic studies.
Authors: SNitter-Hauge, IEnge, B KSembe, K VHall
Journal: Circulation (1979)

The Hall-Kaster pivotal disc prosthetic heart valve was introduced in 1977. The primary goal of the design was to obtain the least possible obstruction to flow. Toward this end, innovations in the tilting axis, disc guidance mechanisms, and disc translational freedom combine to improve flow through both orifice segments of the open valve. The present study reports the primary clinical and hemodynamic findings in 28 patients (mean age, 53.8 years) with aortic valve disease, examined 3 months after insertion of the Hall-Kaster pivotal disc valve. The hemodynamics findings displayed low gradients and high calculated orifice areas. Satisfactory flow was observed through both the major and minor openings of the prosthesis. There were no arterial thromboembolic episodes. The increase in serum lactate dehydrogenase activity was moderate, indicating a slight-to-moderate intravascular haemolysis.
Propranolol and lidocaine inhibit neural norepinephrine release in hearts with increased extracellular potassium and ischemia.
Authors: X JDu, R ARiemersma, K AFox, A MDart
Journal: Circulation (1993)

BACKGROUNDPropranolol and lidocaine are effective antiarrhythmic drugs in myocardial ischemia and infarction. As sympathetic nerve activation and norepinephrine release in ischemic hearts are arrhythmogenic, we tested the possibility that both agents inhibit neural norepinephrine release following sympathetic activation in the ischemic environment.METHODS AND RESULTSThe model used was an in situ perfused innervated rat heart. Norepinephrine release was induced by electrical stimulation of the left cervicothoracic stellate ganglion and analyzed using radioenzymatic assay or high-performance liquid chromatography. In normoxically perfused hearts, evoked norepinephrine release was not affected by either of the two agents at doses of 1 to 10 mumol/L when extracellular K+ concentration was 4 mmol/L but dose-dependently reduced at 10 mmol/L K+ (D,L-propranolol: -53 +/- 4% at 1 mumol/L and -64 +/- 6% at 10 mumol/L K+, lidocaine: -37 +/- 11% at 0.1 mumol/L, -67 +/- 5% at 1 mumol/L, and -75 +/- 6% at 10 mumol/L). ...
Ascorbyl free radical as a real-time marker of free radical generation in briefly ischemic and reperfused hearts. An electron paramagnetic resonance study.
Authors: M KSharma, G RBuettner, K TSpencer, R EKerber
Journal: Circulation Research (1994)

The role of free radicals in myocardial reperfusion injury remains controversial. We have developed a new method using ascorbyl free radical (AFR) as a real-time, quantitative marker of free radical generation during myocardial reperfusion. A total of 35 dogs were studied. Twelve open-chest dogs underwent either 5 minutes (n = 5) or 20 minutes (n = 7) of coronary artery occlusion and 30 minutes of reperfusion. Seven additional animals undergoing 20 minutes of coronary occlusion also received the antioxidant enzymes superoxide dismutase and catalase, beginning 10 minutes before occlusion through the end of reperfusion. Exogenous ascorbate was infused intravenously, and the concentration of AFR in the great cardiac vein was continuously measured by electron paramagnetic resonance spectroscopy. Preocclusion AFR concentration was similar in the three groups. Upon reperfusion, AFR rose significantly in each animal group (P < .05). However, the AFR rise in the 20-minute-occlusion group, 38 +/- 17%, was signific...
Effectiveness, Safety and Clinical Outcomes of Endoscopic Mucosal Resection (EMR) for Large Colorectal Polyps Performed at a District General Hospital
Authors: MG Shiha, T Thomas
Journal: Endoscopy (2021)

Aims Endoscopic mucosal resection (EMR) is an effective and safe alternative to surgery in resecting large colorectal polyps. However, the procedure is technically challenging and often requires referral to specialist centres. We aimed to assess the effectiveness, safety and clinical outcomes of colorectal EMR procedures performed at a United Kingdom-based district general hospital.
Chuvash Polycythemia Patients from Afghanistan and Southern India Share a Common <i>VHL</i> Gene Haplotype. Support for Its Origin before Asians and Europeans Diverged
Authors: Christine Min, Jihyun Song, Joachim R. Goethert, Soo Jin Kim, Victor R. Gordeuk, Josef T. Prchal, Alan Lubin
Journal: Blood (2017)
Safety and Effectiveness of a 2009 H1N1 Vaccine in Beijing
Authors: Nicholas S Kelley, Michael T Osterholm, Edward A Belongia
Journal: New England Journal of Medicine (2011)

To the Editor: The study by Wu et al. (Dec. 16 issue)1 has serious methodologic issues that limit the interpretation of their estimate of the effectiveness of a 2009 pandemic influenza A (H1N1) vaccine. First, the cumulative incidence of influenza was 2.5 times as high in the unvaccinated cohort as in the vaccinated cohort even before a protective effect from the vaccine could have been achieved (Fig. 2 of the article). Because of bias or confounding, these two cohorts did not have the same risk of influenza. In addition, many students may have been infected with the pandemic virus before the study began. Vaccine trials in China that preceded this study reported that 18 to 25% of children who were 12 to 18 years of age were positive for the pandemic H1N1 antibody.2 At one Chinese school, 32% of the students were infected.3 A subsequent serologic survey conducted in Beijing showed that 19.4% of children and young people between 6 and 17 years of age were seropositive for the pandemic virus.4 Yet in the study by Wu et al., less than 0.30% of the unvaccinated cohort and 0.01% of the vaccinated cohort were infected. Numerous cases must have been missed in both cohorts before the study began and while it was being conducted.
Inhibition by diphosphonate compounds of calcification of porcine bioprosthetic heart valve cusps implanted subcutaneously in rats.
Authors: R JLevy, M AHawley, F JSchoen, S ALund, P YLiu
Journal: Circulation (1985)

Calcification limits the long-term success of heart valve bioprostheses fabricated from glutaraldehyde cross-linked porcine aortic valves. The pathophysiology of calcification of bioprostheses has been studied experimentally with subcutaneous implants of the valve cusps in rats; in this preparation, the accumulation of calcific deposits is biochemically and morphologically identical to that occurring in clinical specimens. The objective of the present study was to determine whether mineralization of bioprosthetic valve cusps (BC) subcutaneously implanted in 3-week-old male rats could be inhibited through the use of diphosphonate compounds. Ethanehydroxydiphosphonate (EHDP), administered by daily subcutaneous injection (25 mg/kg/24 hr) for 21 days inhibited calcification (BC Ca++ = 154.9 +/- 4.1), but caused somatic growth retardation and disruption of epiphyseal development. However, local administration of EHDP by osmotic pump (5 mg/kg/24 hr) implanted in direct contact with the cuspal tissue for 14 days...
Heparin decreases activator protein-1 binding to DNA in part by posttranslational modification of Jun B.
Authors: Y PAu, GDobrowolska, D RMorris, A WClowes
Journal: Circulation Research (1994)

Heparin is a potent inhibitor of the proliferation and migration of vascular smooth muscle cells. This agent selectively inhibits the transcription of tissue-type plasminogen activator and interstitial collagenase, probably by decreasing the binding of activator protein-1 (AP-1) to phorbol ester-responsive elements in the promoters of these genes. Decreased AP-1 binding is not due to a direct inhibition by heparin, since heparinase digestion of nuclear extracts prepared from heparin-treated smooth muscle cells does not restore AP-1 binding activity. Treatment of cells with heparin suppresses the expression of Jun B, one of the components of AP-1. The major effect of heparin is at the level of posttranslational modification of Jun B. Results from pulse-chase labeling experiments show that the newly synthesized Jun B is rapidly converted to a higher-molecular-weight form and that conversion is suppressed by heparin. Evidence is presented suggesting that the heparin-inhibited event is phosphorylation of Jun B.
Iron stores are not associated with acute myocardial infarction.
Authors: D MBaer, I STekawa, L BHurley
Journal: Circulation (1994)

BACKGROUNDThis study evaluated the relation between body iron stores and coronary artery disease. It has been suggested that total body iron stores are an independent risk factor for acute myocardial infarction (AMI).METHODS AND RESULTSOur study population consisted of 46,932 members of a prepaid health plan who were > or = 30 years old and who received a standard health check between 1969 and 1971. Blood collected during this examination was analyzed for serum iron and total iron-binding capacity. Transferrin saturation (TS), calculated as (serum iron/total iron-binding capacity) x 100, was categorized as low (  or = 62%). Hospital stays for AMI were identified from the health plan's computerized discharge records for its Northern California Region through December 31, 1991. Mean follow-up time was 14.1 years. During the follow-up period, 969 men and 871 women had an AMI-related hospital stay. Analysis of AMI-related hospital stays was performed overall and ...
Severe Cervical Borborygmi In A 74-Year-Old Patient With A Zenker´s Diverticulum – Boyce’s Sign
Authors: E-M Holley, S Nagl, H Messmann, SK Gölder
Journal: Endoscopy (2021)

Background A Zenker´s diverticulum is located in the dorsal hypopharynx. Common symptoms are dysphagia, regurgitation or Boyce´s sign, a cervical borborygmus.
A place to be born
Authors: J A Davis, S. Clayton, J Richman, J D Baum, C. Cooper, D H Garrow, J A MacFarlane, D MacCarthy, C. Fisher, W O Goodthorp, P J Huntingford, B. Gordon, S. Kitzinger, M Lee-Jones, L I Zander, D. Smith, M Richards, P S B Russell
Journal: BMJ (1976)
College of Anaesthetists?
Authors: P J Baskett, D F Cochrane, A W Diamond, M B Dobson, R Greenbaum, D F Jones, T M O'Carroll, R M Weller, D G Wilkins, S M Willatts, J S Zorab
Journal: BMJ (1979)

develop ways in which health and safety performance can be improved.The HMSO's sectional list 18 (Health and Safety Executive forms and publications) lists many publications, parts of which are now applicable to hospitals and associated areas.Sectional list 18 (Department of Health and Social Security) enumerates many codes, etc.
The implantable transvenous cardioverter: long-term efficacy and reproducible induction of ventricular tachycardia.
Authors: W MMiles, E NPrystowsky, J JHeger, D PZipes
Journal: Circulation (1986)

We followed 11 patients for 5 to 27 months (mean 14.9) after implantation of a permanent transvenous low-energy synchronized cardioverter to evaluate both long-term reproducibility of ventricular tachycardia (VT) induction via noninvasive programmed electrical stimulation with the cardioverter and efficacy of cardioversion. Induction and termination of VT were attempted at implantation and approximately every 3 months thereafter. All patients had coronary artery disease and were receiving antiarrhythmic drug therapy (amiodarone in eight). VT cycle length, morphology, and mode of induction were reproducible on multiple occasions in nine patients; clinical VT was induced inconsistently in two patients. Multiple VT episodes in five patients had one morphology, whereas two morphologies occurred in six patients. Synchronization of the shock within the QRS complex and right ventricular effective refractory periods determined via the cardioverter remained constant over the follow-up period. VT was terminated on ...
Artificial Intelligence Model for the Characterization of Biliary Strictures During Real-Time Digital Cholangioscopy: A Pilot Study
Authors: C Robles-Medranda, R Oleas, J Alcivar-Vasquez, JC Mendez, M Puga-Tejada, R Del Valle, H Pitanga-Lukashok
Journal: Endoscopy (2021)

Aims We aimed to develop an artificial intelligence model for a real-time evaluation during digital cholangioscopy.
Septal geometry in the unloaded living human heart.
Authors: J ALima, P AGuzman, F CYin, R KBrawley, LHumphrey, T ATraill, S DLima, PMarino, M LWeisfeldt, J LWeiss
Journal: Circulation (1986)

Right ventricular loading leads to diastolic septal flattening in man without necessarily requiring right ventricular pressure to exceed left ventricular pressure. This observation suggested that the unstressed septal configuration is flat and that its normal concave shape is due to the left-to-right transseptal pressure gradient. To examine this hypothesis, we studied septal configuration by two-dimensional echocardiography in nine patients with normal global and regional left ventricular function during surgery for coronary artery disease. The transseptal pressure gradient was obtained from pulmonary capillary wedge pressure minus right atrial pressure. Measurements were obtained at control (open chest, intact pericardium [C]), with the pericardium open (OP), on cardiopulmonary bypass (CPB), and after cardiac arrest (CA). There were no changes in any measurements between C and OP or between CPB and CA. Left ventricular end-diastolic cavity area decreased from 16.5 +/- 2.1 cm2 at C to 11.1 +/- 4.5 cm2 af...
Enzymatic indices of myocardial necrosis: influence on short- and long-term prognosis after myocardial infarction.
Authors: P LThompson, E EFletcher, VKatavatis
Journal: Circulation (1979)

The prognostic effect of the peak level of serum creatine kinase (CK) and aspartate transaminase (AST), estimated daily for 3--5 days after acute myocardial infarction, was studied in 560 patients who survived the first day in hospital. In a subgroup of 54 patients, peak enzyme levels correlated well with the cumulated CK release (r = 0.90 with peak CK, r = 0.74 with peak AST), thus reflecting the extent of myocardial necrosis. Total mortality within a year after infarction was not significantly different in the lower three quintiles of peak serum enzyme level, but increased from 15.5% to 27.9% (p less than 0.001) when peak CK level exceeded eight times the upper limit of normal (8 X N) and form 13.1% to 34.8% (p less than 0.001) when peak AST level exceeded five time the upper limit of normal (5 X N). The effect of high enzyme levels was more marked in patients with a prior history of myocardial infarction; mortality increased from 14.7% for first infarctions to 18.2% for recurrent infarctions, with peak...
Reply
Authors: Raquel Yotti, Javier Bermejo, Enrique Gutiérrez-Ibañes, Candelas Pérez del Villar, Teresa Mombiela, Jaime Elízaga, Yolanda Benito, Ana González-Mansilla, Alicia Barrio, Daniel Rodríguez-Pérez, Pablo Martínez-Legazpi, Francisco Fernández-Avilés
Journal: Journal of the American College of Cardiology (2015)
Determinants of end-systolic pressure-volume relations during acute regional ischemia in situ.
Authors: D AKass, PMarino, W LMaughan, KSagawa
Journal: Circulation (1989)

The influence of extent and location of regional ischemia, baseline left ventricular systolic function, and autonomic reflexes on in situ left ventricular end-systolic pressure-volume relations (ESPVRs) during coronary occlusion were studied in 13 open-chest dogs. Circumflex or left anterior descending arteries were randomly occluded (at proximal or distal sites) for 3 minutes in reflex-blocked (n = 6, hexamethonium/vagotomy) and unblocked (n = 7) animals. Pressure-volume data were obtained by the conductance-catheter technique, with ESPVRs determined by transient inferior vena caval occlusion. Ischemic zone size was estimated for each occlusion by radiolabeled microspheres. The relative influence of each variable on ESPVR change with ischemia was determined by multiple regression analysis. As in previous studies, regional ischemia displaced ESPVRs to the right by an amount that varied directly with ischemic bed size (y = +0.48x, r = 0.76, p less than 0.001). However, in contrast to previous data, coronar...
Intravascular ultrasound imaging of human coronary arteries in vivo. Analysis of tissue characterizations with comparison to in vitro histological specimens.
Authors: J MTobis, JMallery, DMahon, KLehmann, PZalesky, JGriffith, JGessert, MMoriuchi, MMcRae, M LDwyer
Journal: Circulation (1991)

BACKGROUNDIntravascular ultrasound imaging was performed in 27 patients after coronary balloon angioplasty to quantify the lumen and atheroma cross-sectional areas.METHODS AND RESULTSA 20-MHz ultrasound catheter was inserted through a 1.6-mm plastic introducer sheath across the dilated area to obtain real-time images at 30 times/sec. The ultrasound images distinguished the lumen from atheroma, calcification, and the muscular media. The presence of dissection between the media and the atheroma was well visualized. These observations of tissue characterization were compared with an in vitro study of 20 human atherosclerotic artery segments that correlated the ultrasound images to histological preparations. The results indicate that high-quality intravascular ultrasound images under controlled in vitro conditions can provide accurate microanatomic information about the histological characteristics of atherosclerotic plaques. Similar quality cross-sectional ultrasound images were also obtained in human corona...
The effects of tension on acetylstrophanthidin-induced transient depolarizations and aftercontractions in canine myocardial and Purkinje tissues.
Authors: G RFerrier
Journal: Circulation Research (1976)

Transmembrane potentials and contractile activity were recorded from isolated canine Purkinje and ventricular muscle preparations exposed to acetylstrophantidin (AS) and subjected to a resting tension equal to 80% of that required to elicit peak developed tension. AS induced transient depolarizations (TD's) accompanied by aftercontractions in Purkinje tissue. AS also induced aftercontractions in 11 muscle preparations, and in seven of these the mechanical events were associated with TD's. Aftercontractions and TD's in both and the coupling intervals were directly related to the preceding basic cycle length (BCL). The amplitudes of aftercontractions and TD's reached a maximum at a coupling interval of 600-700 msec. Tension increased the amplitude of TD's in Purkinje tissue and promoted the appearance of TD's in muscle. TD's in muscle occasionally reached threshold in the presence of tension. The results of this study suggest that stretch or increased resting tension may promote the types of cardiac arrhyth...
Recovery of regional contractile function and oxidative metabolism in stunned myocardium induced by 1-hour circumflex coronary artery stenosis in chronically instrumented dogs.
Authors: G RHeyndrickx, WWijns, DVogelaers, YDegrieck, ABol, GVandeplassche, J AMelin
Journal: Circulation Research (1993)

Stunned myocardium produced by 1 hour of critical coronary artery stenosis was evaluated for alteration in regional mechanical function and overall oxidative and fatty acid metabolism by positron emission tomography (PET) in chronically instrumented dogs. Twenty-seven dogs, chronically instrumented for measurements of left ventricular pressure and regional myocardial wall thickening in normal and ischemic zones, were subjected to a 1-hour period of myocardial ischemia produced by graded left circumflex coronary artery stenosis, resulting in minimal residual flow. Mean transmural myocardial flow during 1-hour coronary stenosis decreased to 0.34 +/- 0.04 ml/min per gram in the ischemic zones (normal zone transmural flow, 0.96 +/- 0.10 ml/min per gram). Systolic wall thickening in the ischemic zone was almost completely abolished (-97 +/- 4%). On reperfusion, systolic wall thickening immediately resumed but remained depressed. Progressive recovery was noted with time. At 24 hours, systolic wall thickening wa...