tbuckley/cabot-search huggingface dataset:
Sudden cardiac death. Support for a role of triggering in causation.
Authors: S NWillich, MMaclure, MMittleman, H RArntz, J EMuller
Journal: Circulation (1993)

Epidemiological studies have identified associations between time of day and risk of sudden cardiac death. The marked peak in the occurrence of sudden cardiac death after awakening suggests that the disease is triggered by changes that occur during this time period. Increased sympathetic stimulation is a likely cause of such triggering. In the light of the circadian variation of sudden cardiac death and the evidence linking physical activity or mental stress (both associated with activation of the sympathetic nervous system) to the disease, the role of potential triggering events should be investigated. Controlled studies are needed to determine the relative risk of activities that may trigger sudden cardiac death. Since such studies must rely on witnesses (or resuscitated patients), data quality must be closely scrutinized, and studies using case-control and case-crossover designs are needed. The epidemiological and pathophysiological data reviewed in the present article suggest a number of pathways thro...
Acute effects of nitrates on exercise testing in patients with syndrome X. Clinical and pathophysiological implications.
Authors: G ALanza, AManzoli, EBia, FCrea, AMaseri
Journal: Circulation (1994)

BACKGROUNDSublingual nitrates are much more effective in relieving angina pectoris in patients with coronary artery disease than in patients with syndrome X, but it is not known whether their effect on exercise tolerance is also different in these two groups of patients.METHODS AND RESULTSTreadmill exercise testing was performed before and after administration of sublingual isosorbide dinitrate (ISDN, 5 mg) in 18 patients with syndrome X (effort angina and normal coronaries, group X) and in 33 patients with documented coronary artery disease (group C). As a selection criterion, all patients had ST-segment depression > or = 1 mm on the control exercise test. Compared with the control test, the main differences in the two groups observed during the exercise test after administration of ISDN were (1) heart rate at 1-mm ST-segment depression was higher (126 +/- 25 versus 104 +/- 15 beats per minute [bpm], P < .01) in group C, whereas it was not different (125 +/- 15 versus 126 +/- 16 beats per minute) in grou...
RE: Breast Cancer Risk After Salpingo-Oophorectomy in Healthy BRCA1/2 Mutation Carriers: Revisiting the Evidence for Risk Reduction
Authors: Xinglei Chai, Susan Domchek, Noah Kauff, Timothy Rebbeck, Jinbo Chen
Journal: JNCI Journal of the National Cancer Institute (2015)

Heemskerk-Gerritsen et al. (1) questioned the protective effect of risk-reducing salpingo-oophorectomy (RRSO) on breast cancer (BC) risk in women who carry a BRCA1 or BRCA2 (BRCA1/2) mutation, as previously reported. They proposed that studies addressing this question should ensure: 1) women are eligible only if they do not have breast or ovarian cancer and have both ovaries and breasts intact before DNA testing; 2) each woman is followed from the age of DNA testing; and 3) the time at risk considers RRSO as a time-dependent variable that takes value 0 before RRSO and 1 after. Using this design, their analysis of Hereditary Breast and Ovarian Cancer in the Netherlands (HEBON) data reported a BC hazard ratio (HR) by RRSO of 1.09 (95% confidence interval [CI] = 0.67 to 1.77). They hypothesized that the previously reported protective effect of RRSO on BC was because of failure to conform to one of these three design features.
Effects of traditional coronary risk factors on rates of incident coronary events in a low-risk population. The Adventist Health Study.
Authors: G EFraser, T MStrahan, JSabaté, W LBeeson, DKissinger
Journal: Circulation (1992)

BACKGROUNDCalifornia Seventh-Day Adventists have lower mortality rates from coronary heart disease (CHD) than other Californians. Associations between traditional risk factor and CHD events have not been reported previously for Adventists.METHODS AND RESULTSA cohort study allowed 6 years of follow-up of 27,658 male and female California Seventh-Day Adventists. Data collected included age, sex, physician-diagnosed hypertension and diabetes mellitus, body height, weight, previous and current cigarette smoking habits, and current exercise habits. Incident cases of definite myocardial infarction (MI) and definite fatal CHD were diagnosed according to recognized criteria. Both stratified and proportional hazards analyses demonstrated that in this low-risk population, the above traditional coronary risk factors exhibit their usual associations with risk of CHD events. It was noted that exercise had a strong negative association with fatal CHD events (relative risks [RR], 1.0, 0.66, and 0.50 with increasing exer...
Prognosis of asymptomatic patients with hypertrophic cardiomyopathy and nonsustained ventricular tachycardia.
Authors: PSpirito, CRapezzi, CAutore, PBruzzi, PBellone, POrtolani, P VFragola, FChiarella, MZoni-Berisso, ABranzi
Journal: Circulation (1994)

BACKGROUNDIn the early 1980s, studies performed in highly selected referral patients with hypertrophic cardiomyopathy reported a strong association between the presence of brief episodes of ventricular tachycardia (VT) on ambulatory ECG monitoring and sudden death. These observations led to antiarrhythmic treatment in many patients with hypertrophic cardiomyopathy and brief episodes of VT. In recent years, however, a growing awareness of the potential arrhythmogenic effects of antiarrhythmic medications has raised doubts regarding such a therapeutic approach, particularly in less selected and lower-risk patient populations.METHODS AND RESULTSIn the present study, we examined the prognostic significance of nonsustained VT in a population of 151 patients with hypertrophic cardiomyopathy who were asymptomatic or had only mild symptoms at the time of their initial ambulatory ECG recording. Of the 151 study patients, 42 had episodes of VT and 109 did not. The runs of VT ranged from 3 to 19 beats, with 35 patie...
What If Americans Ate Less Fat?
Authors: Richard A. Williams
Journal: JAMA (1992)

<h3>To the Editor.</h3> —As many of your readers may know, the Food and Drug Administration currently is developing regulations to enforce the Nutrition Labeling and Education Act of 1990, which mandates sweeping changes in the information presented on food labels. We recently estimated the benefits of the proposed nutrition label changes using the model described in a recent<i>JAMA</i>article "What If Americans Ate Less Fat?" by Browner et al.<sup>1</sup> We are concerned that physicians will interpret results like those of Browner et al to mean that patients should not be advised to change their diets. The results of the study by Browner et al demonstrated a modest 3- to 4-month increase in average life expectancy due to a change in fat intake from a "best" diet. However, using a population average to summarize the effects of all consumers changing their diet obscures larger increases in individual longevity. For
Echocardiographic features of constrictive pericarditis.
Authors: A GVoelkel, D APietro, E DFolland, M LFisher, A FParisi
Journal: Circulation (1978)

The most characteristic echocardiographic features of 12 patients with constrictive pericarditis were compared with the findings in 10 normal volunteers. Left ventricular posterior wall (LVPW) flatness was quantified by measuring the diastolic change in distance from the crystal artifact to the LVPW endocardium. In 11 of 12 patients the net diastolic LVPW endocardial movement was less than 1 mm. In 10 normal volunteers LVPW endocardium moved posteriorly in diastole from 1.5 to 4 mm (mean 2.2 +/- 0.8). Abnormal septal motion was present in five of 12 patients with constriction. Pericardial thickness measured using standard damping techniques for both cnstriction and normal population did not distinguish the two groups. The flattening of the left ventricular endocardium as quantified above verifies earlier qualitative observations and was the most consistent finding in this series of patients with constrictive pericarditis.
The Role Of Spectral Focused Imaging In Diagnosing Subtle Mucosal Changes In Ulcerative Colitis Patients
Authors: A Ghidersa, Tîrcol SA, L Negreanu, M State, A Dumitru
Journal: Endoscopy (2021)

Aims The aim of this pilot study was to determine whether virtual chromoendoscopy, represented by SFI, a new optical chromoendoscopy system (from SonoScape) has the potential to enhance the rate of detection for subtle mucosal changes in patients with mild or inactive forms of ulcerative colitis (UC) in comparison to high definition white light endoscopy (HD-WLE).
Eus Guided Choledochoduodenostomy With Electrocautery Enhanced Lumen Apposing Metal Stents in the Treatment of Malignant Distal Biliary Obstruction: Multi-Centre Collaboration From the Uk and Ireland
Authors: W On, B Paranandi, AM Smith, A Young, J Pine, SV Venkatachalapathy, MW James, GP Aithal, I Varbobitis, D Cheriyan, C McDonald, JS Leeds, M Nayar, K Oppong, J Geraghty, J Devlin, W Ahmed, R Scott, T Wong, MT Huggett
Journal: Endoscopy (2021)

Aims Endoscopic ultrasound guided choledochoduodenostomy (EUS-CDD) with electrocautery enhanced lumen apposing metal stents (EC-LAMS) has recently emerged as a viable option in the management of patients with malignant distal biliary obstruction (MDBO). We conducted a multi-centre collaboration from the UK and Ireland with an aim to analyse the pooled efficacy, safety and long term outcomes of EUS-CDD for treatment of MDBO.
Attenuation of exercise-induced myocardial ischemia in dogs with recruitment of coronary vasodilator reserve by nifedipine.
Authors: GHeusch, B DGuth, RSeitelberger, JRoss
Journal: Circulation (1987)

There is now evidence that under resting conditions coronary vasodilator reserve exists even in the presence of myocardial ischemia. Therefore, we tested the hypothesis that a vasodilator reserve may exist during exercise so that during exercise-induced ischemia a reduction in coronary constrictor tone can be produced that attenuates the decreases in regional myocardial blood flow and function distal to a severe coronary stenosis without changing the determinants of myocardial oxygen demand. Nine dogs were instrumented with an ameroid constrictor on the left circumflex coronary artery and were studied 2 to 3 weeks later. During a control treadmill run, heart rate increased from 119 +/- 20 to 225 +/- 20 beats/min and peak left ventricular pressure increased from 144 +/- 17 to 163 +/- 28 mm Hg. Poststenotic subendocardial blood flow (measured by a microsphere technique) fell from 1.19 +/- 0.36 to 0.51 +/- 0.30 ml/min X g and systolic wall thickening (by sonomicrometry) decreased from 24.3 +/- 5.8% to 6.0 +/...
Determinants of ventricular tachycardia in patients with ventricular aneurysms: results of intraoperative epicardial and endocardial mapping.
Authors: IWiener, BMindich, RPitchon
Journal: Circulation (1982)

We performed epicardial and endocardial mapping in 11 patients with ventricular aneurysms; six had chronic, recurrent ventricular tachycardia and five had no ventricular arrhythmias more severe than isolated ventricular premature complexes. Forty to 66 epicardial and 16-40 endocardial points were recorded during stable sinus rhythm in each patient. Local electrograms were evaluated as to timing and presence of fragmentation (duration greater than 50 msec, amplitude less than 1 mV, absence of discrete intrinsicoid deflection). Activation of the epicardial surface of the aneurysm was abnormal in all patients, and extended beyond completion of the QRS in three patients in the arrhythmia group and two in the nonarrhythmia group (NS). Activation of the epicardial border zone was normal in all patients. Electrograms from the endocardial surface of the aneurysm were abnormally fragmented in all patients and the mean duration of activation was not different between patients with and without arrhythmias (85.5 +/- ...
Cholinergic constriction in the general circulation and its role in coronary artery spasm.
Authors: SKalsner
Journal: Circulation Research (1989)

The release of acetylcholine from autonomic nerves in those tissues that receive a cholinergic innervation is widely believed to dilate blood vessels. Exogenously administered acetylcholine in vivo does dilate vascular beds and produce hypotension; however, this latter effect is indirect and probably the result of liberation of endothelium-derived relaxing factor (EDRF) from endothelial cells. Some blood vessels contain a substantial population of medial constrictor receptors for acetylcholine, and the implications of this presence for vascular control systems has been largely ignored, although it needs to be considered. A survey of the evolution of vasomotor control systems indicates that acetylcholine serves principally as an excitatory transmitter to blood vessels. Neurally mediated cholinergic constriction and not dilation is found in fish, amphibians, reptiles, and birds, with responses initiated by medial muscarinic receptors. Acetylcholine constricts many vascular preparations from these lower anim...
In vivo lymphocyte-mediated myocardial injuries demonstrated by adoptive transfer of experimental autoimmune myocarditis.
Authors: MKodama, YMatsumoto, MFujiwara
Journal: Circulation (1992)

BACKGROUNDTo elucidate the mechanisms of immune-related myocardial injuries, we examined whether autoimmune myocarditis was passively transferable by use of humoral or cellular factors.METHODS AND RESULTSActive myocarditis was elicited in Lewis rats by immunization with human cardiac myosin fraction in complete Freund's adjuvant. This experimental myocarditis was characterized by macroscopic features such as pericardial effusion, enlargement of the heart, and gray discoloration of the cardiac surface. Histologically, extensive myocardial necrosis and numerous inflammatory cell infiltrations were observed. Interestingly, multinucleated giant cells were frequently observed in the lesions. Transfer of the disease by the humoral factor was examined by use of fresh sera and immunoglobulin fraction of pooled sera from rats with severe myocarditis, and transfer by the cellular factor was tested by use of spleen cells and lymph node cells from the diseased rats. When naive Lewis rats were given 15.75 mg of immuno...
Endothelin antiserum decreases volume-stimulated and basal plasma concentration of atrial natriuretic peptide.
Authors: FFyhrquist, M LSirviö, KHelin, OSaijonmaa, KMetsärinne, IPaakkari, AJärvinen, ITikkanen
Journal: Circulation (1993)

BACKGROUNDEndothelin-1 (ET-1) is the most powerful factor known to release atrial natriuretic peptide (ANP) in vivo and in cultured cardiac myocytes or preparations of atrium. We tested the role of endogenous ET-1 in the regulation of ANP release by passive immunization in anesthetized rats.METHODS AND RESULTSIntravenous injection of antiserum against ET-1 was shown to decrease basal and volume-stimulated plasma concentrations of ANP, whereas control serum was without effect. Antiserum generated in rabbits cross-reacted 100% with endothelin-2 and -3. In pentobarbital-anesthetized Wistar rats treated with ET-1 antiserum, plasma ANP concentration measured by radioimmunoassay was reduced by 37% from starting level after 10 minutes and by 30% after 60 minutes. Control rat serum had no effect on plasma ANP. Rapid intravenous infusion of 8 mL of 0.9% NaCl caused a sixfold increase of plasma ANP concentration in control rats but only twofold in rats pretreated with ET-1 antiserum (P < .01). This effect of ET-1 a...
Association Between Risk Factors for Complications From COVID-19, Perceived Chances of Infection and Complications, and Protective Behavior in the US
Authors: Robert F. Schoeni, Emily E. Wiemers, Judith A. Seltzer, Kenneth M. Langa
Journal: JAMA Network Open (2021)

<h3>Importance</h3> It is unknown whether adults who are susceptible to severe complications from COVID-19 recognize their susceptibility and modify behavior to reduce exposure. <h3>Objective</h3> To determine whether adults with risk factors for COVID-19 complications perceive an elevated chance of complications and undertake fewer higher infection risk behaviors. <h3>Design, Setting, and Participants</h3> This cross-sectional analysis, adjusted for sociodemographic characteristics, included civilian noninstitutionalized US adults of wave 18 of the Understanding America Study collected from November 11 to December 9, 2020. <h3>Exposures</h3> US Centers for Disease Control and Prevention–identified medical risk factors for COVID-19 complications and older age. <h3>Main Outcomes and Measures</h3> Primary outcomes were perceived percentage chance of infection and hospitalization and death if infected; whether 9 potentially higher infection risk activities were undertaken in the past week and, if so, whether a mask was worn; whether a mask was worn anywhere in the past week; and attitudes toward 12 aspects of mask wearing. <h3>Results</h3> In Understanding America Study wave 18 (n = 5910 participants with nonmissing data), the mean age was 48 years, and 52% were women. The response rate was 77%. Adults with 7 of 9 medical risk factors and aged 70 years and older reported a higher perceived chance of complications if infected. Adjusted mean perceived chance of hospitalization if infected ranged from 23.9% (95% CI, 22.2%-25.5%) for those with high blood pressure to 40.4% (95% CI, 34.6%-46.2%) for those with chronic lung disease and was associated with number of medical risk factors: 17.6% (95% CI, 16.4%-18.8%) and 41.8% (95% CI, 38.7%-45.0%) for adults with 0 vs 3 or more medical risk factors, respectively. Fewer potentially higher infection risk activities were undertaken by adults with 3 or more vs 0 risk factors: 2.83 (95% CI, 2.66-2.99) vs 3.12 (95% CI, 3.02-3.22). Wearing a mask sometime last week was nearly universal (90.1%). But during only 1 specific activity (visiting a grocery store or pharmacy) did more than half always wear a mask, and for only 1 activity (visiting a grocery store or pharmacy) was mask wearing more common among adults with 3 or more vs 0 conditions. <h3>Conclusions and Relevance</h3> In this cross-sectional survey study, adults with risk factors for COVID-19 complications reported higher perceived susceptibility to complications. During common activities, including visiting with friends, the majority of adults, including the highly susceptible, did not consistently wear masks.
Release of endogenous catecholamines in the ischemic myocardium of the rat. Part B: Effect of sympathetic nerve stimulation.
Authors: A MDart, ASchömig, RDietz, EMayer, WKübler
Journal: Circulation Research (1984)

The contribution of centrally originating sympathetic activity to the myocardial extracellular accumulation of noradrenaline during the early phase of ischemia has been assessed in a perfused (Langendorff) rat heart preparation isolated except for its sympathetic innervation. A 10-minute electrical stimulation (4 Hz, 5 V) of the left cervicothoracic ganglion during normal perfusion causes the overflow of 177.5 +/- 13.7 pmol noradrenaline/g heart, whereas such stimulation during ischemia liberates only 21.5 +/- 3.6 pmol/g (collected during reperfusion). When neuronal reuptake is blocked by desipramine, corresponding values are 321.5 +/- 22.5 pmol/g (normal flow) and 151.8 +/- 22.4 pmol/g (ischemia). After combined blockade of neuronal uptake, extraneuronal uptake, and alpha 2-receptors, nerve stimulation liberates 674 +/- 22 pmol/g during normal flow and 206 +/- 24.3 pmol/g during ischemia. These results suggest that, in vivo, centrally originating neural activity would not lead to substantial accumulation...
Frequency- and orientation-dependent effects of mexiletine and quinidine on conduction in the intact dog heart.
Authors: A KBajaj, H AKopelman, J PWikswo, FCassidy, R LWoosley, D MRoden
Journal: Circulation (1987)

Myocardial conduction depends on the magnitude of the fast inward sodium current as well as on cardiac fiber orientation, with more rapid propagation along myocardial fibers than across them. Although antiarrhythmic drugs depress the sodium current in a frequency-dependent fashion in vitro, their effects on conduction in the intact ventricle have been less well studied. We therefore evaluated the frequency- and orientation-dependent actions of mexiletine, quinidine, and their combination on epicardial conduction in 24 pentobarbital-anesthetized dogs. These interventions were chosen because the time constant of recovery from sodium-channel blockade by mexiletine in vitro is shorter than that from blockade by quinidine, and because we have previously shown that the combination of these drugs is often clinically effective when single-agent therapy fails. An electrode array that permitted measurement of conduction times in multiple orientations over short segments of epicardium without contamination by rapid ...
208P Safety and efficacy of immune checkpoint inhibitors in NSCLC patients with autoimmune disease: A UK tertiary cancer centre experience
Authors: P. Sawhney, G. Patel, D. Ohana, M.K. Luong, Y.N.S. Wong, A.J.X. Lee, S-M. Lee, M.D. Forster
Journal: Journal of Thoracic Oncology (2021)
The Björk-Shiley aortic prosthesis: flow characteristics, thrombus formation and tissue overgrowth.
Authors: A PYoganathan, W HCorcoran, E CHarrison, J RCarl
Journal: Circulation (1978)

Thrombus formation and tissue overgrowth were observed in nine Bjork-Shiley aortic prostheses recovered six months or longer after implantation. These pathologic findings may be attributed to the flow characteristics of the prosthesis. The open disc of the valve separates the flow into two unequal regions. Varying degrees of thrombus formation were observed in the minor outflow region, including the depression in the aortic face of the disc and the metal strut bridging this area. Tissue overgrowth was noted along the perimeter of the prosthesis adjacent to the minor outflow region. That overgrowth further reduced the available cross section for flow in this already constrained area. In vitro velocity measurements with a laser-Doppler anemometer identified a zone of stagnation about 20 mm wide near the aortic face of the disc. The average velocities in the major and minor outflow regions were around 100 and 25 cm/sec, respectively, and the corresponding peak-shear stresses were approximately 700 and 150 dy...
Microbiome meta-analysis and cross-disease comparison enabled by the SIAMCAT machine learning toolbox
Authors: Jakob Wirbel, Konrad Zych, Morgan Essex, Nicolai Karcher, Ece Kartal, Guillem Salazar, Peer Bork, Shinichi Sunagawa, Georg Zeller
Journal: Genome biology (2021)

Abstract The human microbiome is increasingly mined for diagnostic and therapeutic biomarkers using machine learning (ML). However, metagenomics-specific software is scarce, and overoptimistic evaluation and limited cross-study generalization are prevailing issues. To address these, we developed SIAMCAT, a versatile R toolbox for ML-based comparative metagenomics. We demonstrate its capabilities in a meta-analysis of fecal metagenomic studies (10,803 samples). When naively transferred across studies, ML models lost accuracy and disease specificity, which could however be resolved by a novel training set augmentation strategy. This reveals some biomarkers to be disease-specific, with others shared across multiple conditions. SIAMCAT is freely available from siamcat.embl.de .