tbuckley/cabot-search huggingface dataset:
Ventricular tachycardia in infancy: evidence for a reentrant mechanism.
Authors: W EGaum, D CSchwartz, SKaplan
Journal: Circulation (1980)

Ventricular tachycardia is unusual in infancy. Three infants are described in whom this arrhythmia was documented by electrophysiologic studies. The ability to start and terminate this rhythm by critically timed premature ventricular stimulation suggests a reentrant mechanism. All three patients have remained free of arrhythmias on oral propranolol therapy.
Renal function and urate metabolism in late survivors with cyanotic congenital heart disease.
Authors: E ARoss, J KPerloff, G MDanovitch, J SChild, M MCanobbio
Journal: Circulation (1986)

Diminished glomerular filtration rate, proteinuria, and large hypercellular congested glomeruli with segmental sclerosis are found in late survivors with cyanotic congenital heart disease (CCHD). Hyperuricemia is common, acute gouty arthritis is less common than uric acid levels would predict, and overt tophaceous deposits of uric acid are exceptional. The role of the kidney in causing the basic biochemical disturbances, and the relative importance of impaired urate excretion vs urate overproduction have not been established. Accordingly, we reviewed the courses of two index patients and prospectively studied eight additional CCHD patients from 28 years to 46 years old with mean hematocrits of (62 +/- 10%). Plasma creatinine concentration was normal (0.9 +/- 0.1 mg/dl) yet glomerular filtration rate was mildly reduced to 93 +/- 14 ml/min as measured by creatinine clearance and to 81 +/- 6 ml/min as measured by 111In DTPA. Three patients had significant proteinuria and one was nephrotic. Plasma uric acid c...
Racial Justice and Economic Efficiency Both Require Ending the War on Drugs
Authors: Pierre-André Chiappori, Kristina Orfali
Journal: The American Journal of Bioethics (2021)

The paper by Earp, Lewis, and Hart (2021) offers a strong criticism of the so-called “war on drugs.” The authors very convincingly argue that the war “has worsened many aspects of public health whi...
Adaptations of the left ventricle to chronic pressure overload.
Authors: SSasayama, JRoss, DFranklin, C MBloor, SBishop, R BDilley
Journal: Circulation Research (1976)

Left ventricular (LV) function during the adaptation to chronic pressure overload produced by an ascending aortic constriction was analyzed in conscious dogs, instrumented with intraventricular micromanometers and pairs of ultrasonic crystals for measurement of LV wall thickness (WTh) and internal LV chamber diameter. During inflation of the cuff to produce LV pressures averaging 220 mg Hg, calculated peak wall stress (WSt) increased by 55% above control while percent shortening decreased by 24% and mean circumferential shortening velocity (VCF) decreased by 39% from control. By 9 days (mean) after aortic constriction, the cross-sectional area (CSA) of the LV wall increased by 10% and peak WSt fell to 37% above control. End-diastolic diameter (EDD) increased to 4% above control, while percent shortening and mean VCF remained reduced at -12% and -20% of control, respectively. During the phase of concentric hypertrophy (mean 2 1/2 weeks), CSA increased further to 15% above control and WSt fell to 22% above ...
Loss of the coronary microvascular response to acetylcholine in cardiac transplant patients.
Authors: C BTreasure, J AVita, PGanz, T JRyan, F JSchoen, V IVekshtein, A CYeung, G HMudge, R WAlexander, A PSelwyn
Journal: Circulation (1992)

BACKGROUNDThe coronary arteries of transplanted hearts frequently develop accelerated diffuse arteriosclerosis. The effects of this disease on resistance vessel function are unknown.METHODS AND RESULTSTo investigate the integrity of endothelium-dependent small-vessel vasodilation in transplanted hearts, coronary blood flow (CBF) responses to the endothelium-dependent dilator acetylcholine (10(-8) to 10(-6) M) and the essentially endothelium-independent dilator adenosine (10(-6) to 10(-4) M) were assessed in 40 studies of 29 transplant patients 1-3 years after transplantation and in seven nontransplanted controls. CBF was measured at constant arterial pressure with a Doppler catheter in the left anterior descending coronary artery. Controls, year 1 transplant patients, and year 2 transplant patients had similar increases in CBF in response to acetylcholine (232 +/- 40%, 200 +/- 41%, and 201 +/- 54%, respectively; p = NS), whereas year 3 transplant patients had increased CBF of only 100 +/- 39% (p less than...
Natural history of aortoarteritis (Takayasu's disease).
Authors: RSubramanyan, JJoy, K GBalakrishnan
Journal: Circulation (1989)

The natural history of aortoarteritis was studied in 88 patients (54 women and 34 men). The average age was 24.0 +/- 8.8 years at onset of symptoms and 28.3 +/- 9.9 years at diagnosis. The follow-up period was 83.6 +/- 74.4 months from onset and 33.2 +/- 37.0 months from diagnosis. Ten patients (11.4%) died during follow-up (0.016 deaths/patient year), and 22 patients (25%) suffered major nonfatal events (0.042 events/patient year). The cumulative survival at 5 and 10 years after the onset was 91.0 +/- 3.3% and 84.0 +/- 5.6% (mean +/- SEM), respectively. The event-free survival rates at the same intervals after onset were 74.9 +/- 5.0% and 64.0 +/- 7.4%, respectively. The overall survival and event-free survival at 10 years after diagnosis was 80.3 +/- 6.5% and 61.6 +/- 7.5%, respectively. Patients with no complications or a mild single complication at diagnosis had a higher event-free survival rate than those with severe single complication or multiple complications at 5 years--97.0 +/- 2.9% and 59.7 +/-...
Effect of sudden rate acceleration on the human His-Purkinje system: adaptation of refractoriness in a dampened oscillatory pattern.
Authors: P JTchou, M HLehmann, JDongas, RMahmud, S TDenker, MAkhtar
Journal: Circulation (1986)

Although the refractoriness of the human His-Purkinje system (HPS) during constant-cycle length pacing appears to be closely related to the cycle length of the stimulation, the mode of adaptation of this refractoriness with sudden rate acceleration is not well understood. A systematic evaluation of this adaptation was performed in 14 patients with normal QRS durations and HV intervals referred for electrophysiologic evaluation. The relative refractory period of the HPS (HPS-RRP) was evaluated by the extrastimulus (S2) method during a constant ventricular drive (S1) having a cycle length as close to sinus rhythm as possible. An accelerated train of 6 ventricular beats (S1') was then added to the constant drive and the HPS-RRP of each successive beat of this train was similarly determined. Mean S1 cycle length was 750 +/- 164 msec (range 600 to 1000). Mean S1' cycle length was 475 +/- 55 msec (range 400 to 600). The HPS-RRP of each successive beat of the accelerated train was significantly shorter than that...
Mechanism of interruption of atrial flutter by moricizine. Electrophysiological and multiplexing studies in the canine sterile pericarditis model of atrial flutter.
Authors: JOrtiz, ANozaki, AShimizu, CKhrestian, YRudy, A LWaldo
Journal: Circulation (1994)

BACKGROUNDMoricizine is said to have potent effects on cardiac conduction but little or no effect on cardiac refractoriness.METHODS AND RESULTSThe effects of moricizine (2 mg/kg IV) on induced atrial flutter were studied 2 to 4 days after the creation of sterile pericarditis in 11 dogs. Ten episodes of stable atrial flutter before and after the administration of moricizine were studied in 9 dogs in the conscious, nonsedated state, and 7 episodes were studied in 6 dogs in the anesthetized, open chest state. In the conscious state, the effects of moricizine on atrial excitability, atrial effective refractory period, and intra-atrial conduction times were studied by recording during overdrive pacing of sinus rhythm from epicardial electrodes placed at selected atrial sites. Moricizine prolonged the atrial flutter cycle length in all the episodes, from a mean of 133 +/- 9 to 172 +/- 27 milliseconds (P < .001), and then terminated 7 of the 10 episodes. Moricizine increased the atrial threshold of excitability ...
Prejunctional inhibition of norepinephrine release caused by acetylcholine in the human saphenous vein.
Authors: D KRorie, N JRusch, J TShepherd, P MVanhoutte, G MTyce
Journal: Circulation Research (1981)

We performed experiments to determine whether or not acetylcholine exerts a prejunctional inhibitory effect on adrenergic neurotransmission in the human blood vessel wall. Rings of human greater saphenous veins were prepared 2 to 15 hours after death and mounted for isometric tension recording in organ chambers filled with Krebs-Ringer solution. Acetylcholine depressed contractile responses to electric activation of the sympathetic nerve endings significantly more than those to exogenous norepinephrine; the relaxations caused by the cholinergic transmitter were antagonized by atropine. Helical strips were incubated with [3H]norepinephrine and mounted for superfusion. Electric stimulation augmented the fractional release of labeled norepinephrine. Acetylcholine caused a depression of the evoked 3H release which was antagonized by atropine but not by hexamethonium. These experiments demonstrate that, as in animal cutaneous veins, there are prejunctional inhibitory muscarinic receptors on the adrenergic nerv...
Diagnosis of deep venous thrombosis. A prospective study comparing duplex scanning to contrast venography.
Authors: L AKillewich, G RBedford, K WBeach, D EStrandness
Journal: Circulation (1989)

Duplex scanning has been proposed as a safe alternative to contrast venography for diagnosing deep venous thrombosis, but its accuracy has not been proved. In this prospective, double-blind study of 47 patients, the sensitivity and specificity of duplex scan criteria were determined relative to contrast venography for lower extremity deep venous thrombosis. Criteria considered to show the presence of deep venous thrombosis included visualization of thrombus (T), absence of spontaneous flow by Doppler ultrasonography (F), absence of phasicity of flow with respiration (P), and incompressibility of the vein with probe pressure (VC). When analyzed individually, the variables T and F had low sensitivities (50% and 76%) but high specificities (92% and 100%). VC had low values for both (79% and 67%, respectively). The best single variable was P (sensitivity and specificity = 92%). The best combinations of variables were T+P (sensitivity = 95%, specificity = 83%), T+F+P (sensitivity = 95%, specificity = 83%), F+P...
Regression of myocardial hypertrophy: electrocardiographic-echocardiographic correlations after aortic valve replacement in patients with chronic aortic regurgitation.
Authors: J DCarroll, W HGaasch, SNaimi, H JLevine
Journal: Circulation (1982)

Serial electrocardiographic and echocardiographic left ventricular (LV) studies were performed in 21 patients before and after aortic valve replacement (AVR) for chronic aortic regurgitation. Changes in voltage (SV1 + RV5-6) after AVR were assessed and evaluated relative to changes in LV mass. Muscle cross-sectional area (CSA) derived from echocardiographic dimension and wall thickness data was used as an index of LV muscle mass (LV hypertrophy greater than 10 cm2/m2). In 15 patients, voltage was reduced after AVR: Seven had normal voltage (48 +/- 17 mm to 25 +/- 6 mm, p less than 0.005) and eight still had increased voltage (61 +/- 17 mm to 40 +/- 4 mm, p less than 0.01). Patients with normal voltage had complete regression of hypertrophy by echocardiography (CSA decreased from 13 +/- 3 cm2/m2 to 9 +/- 1 cm2/m2, p less than 0.025), while those who had persistently increased voltage had incomplete regression (15 +/- 2 cm2/m2, p less than 0.001). Reduction in voltage generally occurred in the first 6 month...
Simultaneous aortic, jugular bulb, and right atrial pressures during cardiopulmonary resuscitation in humans. Insights into mechanisms.
Authors: N AParadis, G BMartin, M GGoetting, J MRosenberg, E PRivers, T JAppleton, R MNowak
Journal: Circulation (1989)

Pressure gradients across and between the head and chest were studied during mechanical cardiopulmonary resuscitation (CPR) in 22 humans. Patients in medical cardiac arrest, managed by ACLS guidelines, underwent placement of aortic arch (Ao), jugular venous bulb (JVB), and right atrial (RA) catheters. Simultaneous pressures were measured, and intercatheter gradients were calculated. The JVB to RA pressure difference is the gradient between the cervical and central venous circulations. It was negative when averaged throughout the CPR cycle and was more negative during compression than relaxation, -19 +/- 12 and -2 +/- 6 mm Hg, respectively. This indicates that the intrathoracic pressure rise was not transmitted to the jugular venous system, supporting the concept of a competent jugular valve mechanism during CPR. It is consistent with the thoracic pump model of cerebral perfusion. JVB to RA was positive only during early relaxation, allowing blood return from the head. The Ao to JVB gradient, although not ...
Pneumonitis and pulmonary fibrosis associated with amiodarone treatment: a possible complication of a new antiarrhythmic drug.
Authors: S MSobol, LRakita
Journal: Circulation (1982)

Six patients are presented who developed pulmonary infiltrates of undetermined origin while being treated for severe ventricular arrhythmias with amiodarone hydrochloride. Biopsy material was available in four patients and revealed interstitial or alveolar fibrosis and pneumonitis. Four patients recovered and two died of severe cardiopulmonary decompensation; all of the patients who recovered received corticosteroid therapy. Pulmonary fibrosis is a previously unreported complication of amiodarone therapy.
Cytokine and murine coxsackievirus B3 myocarditis. Interleukin-2 suppressed myocarditis in the acute stage but enhanced the condition in the subsequent stage.
Authors: CKishimoto, YKuroki, YHiraoka, HOchiai, MKurokawa, SSasayama
Journal: Circulation (1994)

BACKGROUNDIt has been shown that the development of coxsackievirus B3 (CB3) myocarditis is regulated by T cells and not by B cells. Interleukin-2 (IL-2) is a T-cell-derived cytokine that stimulates the growth of T cells. This study was carried out to determine the effects of IL-2 on CB3-infected BALB/c mice.METHODS AND RESULTSIn two separate experiments, recombinant human IL-2 (5 x 10(4) U) was administered subcutaneously to 30 mice early (days 0 to 7) and 30 mice late (days 7 to 14) after infection with CB3. Each experiment had a control group of infected animals that did not receive IL-2. On days 7 and 10, splenic natural killer (NK) cell activity determined by 51Cr release assay and the distribution of myocardial lymphocyte subsets were compared in the treated and untreated groups. In the early treatment experiment, survival at 7 days was higher in treated compared with control animals, myocardial virus titers were lower, inflammatory cell infiltration was less (as was the severity of necrosis at the t...
CaDIS: Cataract dataset for surgical RGB-image segmentation
Authors: Maria Grammatikopoulou, Evangello Flouty, Abdolrahim Kadkhodamohammadi, Gwenolé Quellec, Andre Chow, Jean Nehme, Imanol Luengo, Danail Stoyanov
Journal: Medical Image Analysis (2021)

Video feedback provides a wealth of information about surgical procedures and is the main sensory cue for surgeons. Scene understanding is crucial to computer assisted interventions (CAI) and to post-operative analysis of the surgical procedure. A fundamental building block of such capabilities is the identification and localization of surgical instruments and anatomical structures through semantic segmentation. Deep learning has advanced semantic segmentation techniques in the recent years but is inherently reliant on the availability of labelled datasets for model training. This paper introduces a dataset for semantic segmentation of cataract surgery videos complementing the publicly available CATARACTS challenge dataset. In addition, we benchmark the performance of several state-of-the-art deep learning models for semantic segmentation on the presented dataset. The dataset is publicly available at https://cataracts-semantic-segmentation2020.grand-challenge.org/.
Effect of cyclic mechanical loading on immunoinflammatory microenvironment in biofabricating hydroxyapatite scaffold for bone regeneration
Authors: Penghui Zhang, Xizhe Liu, Peng Guo, Xianlong Li, Zhongyuan He, Zhen Li, Martin J. Stoddart, Sibylle Grad, Wei Tian, Dafu Chen, Xuenong Zou, Zhiyu Zhou, Shaoyu Liu
Journal: Bioactive Materials (2021)

It has been proven that the mechanical microenvironment can impact the differentiation of mesenchymal stem cells (MSCs). However, the effect of mechanical stimuli in biofabricating hydroxyapatite scaffolds on the inflammatory response of MSCs remains unclear. This study aimed to investigate the effect of mechanical loading on the inflammatory response of MSCs seeded on scaffolds. Cyclic mechanical loading was applied to biofabricate the cell-scaffold composite for 15 min/day over 7, 14, or 21 days. At the predetermined time points, culture supernatant was collected for inflammatory mediator detection, and gene expression was analyzed by qRT-PCR. The results showed that the expression of inflammatory mediators (IL1B and IL8) was downregulated (p < 0.05) and the expression of ALP (p < 0.01) and COL1A1 (p < 0.05) was upregulated under mechanical loading. The cell-scaffold composites biofabricated with or without mechanical loading were freeze-dried to prepare extracellular matrix-based scaffolds (ECM-based scaffolds). Murine macrophages were seeded on the ECM-based scaffolds to evaluate their polarization. The ECM-based scaffolds that were biofabricated with mechanical loading before freeze-drying enhanced the expression of M2 polarization-related biomarkers (Arginase 1 and Mrc1, p < 0.05) of macrophages in vitro and increased bone volume/total volume ratio in vivo. Overall, these findings demonstrated that mechanical loading could dually modulate the inflammatory responses and osteogenic differentiation of MSCs. Besides, the ECM-based scaffolds that were biofabricated with mechanical loading before freeze-drying facilitated the M2 polarization of macrophages in vitro and bone regeneration in vivo. Mechanical loading may be a promising biofabrication strategy for bone biomaterials.
Heart-specific targeting of firefly luciferase by the myosin light chain-2 promoter and developmental regulation in transgenic mice.
Authors: W MFranz, DBreves, KKlingel, GBrem, P HHofschneider, RKandolf
Journal: Circulation Research (1993)

Based on hybridization studies indicating constitutive expression levels of the endogenous myosin light chain-2 (MLC-2) gene in embryonic, fetal, and adult myocardium, a model system for selective targeting of genes to the heart of transgenic mice has been developed. A 2.1-kb DNA fragment of the 5' flanking region of the rat cardiac MLC-2 gene was fused to the firefly luciferase reporter gene and introduced into fertilized mouse oocytes. In four independent transgenic mouse lines, the expression of the MLC-2-luciferase fusion gene was found exclusively in heart muscle. In contrast to the endogenous MLC-2 gene, no luciferase activity was detectable in slow-twitch skeletal muscle or any other tissue of transgenic mice. This result suggests that the 2.1-kb DNA fragment of the 5' flanking region of the cardiac MLC-2 gene contains the regulatory elements required for selective gene expression in cardiac myocytes in vivo. In contrast to the endogenous steady-state MLC-2 expression during development, transgenic...
Actual causes of death in the United States
Authors: R. R. White
Journal: JAMA (1994)

To the Editor.  —In the Review by Drs McGinnis and Foege,1no specific reference is made to lives lost to abortion.  Under the heading Sexual Behavior, they mention 5000 deaths from excess infant mortality rates among those whose pregnancies were unintended.2Informal estimates range from more than 1 million to approaching 2 million US deaths a year to abortion, but hard data are sorely needed. The total number of deaths reported by McGinnis and Foege for 1990 was only 1 060 000. If such a massive loss of life to a single cause, such as abortion, could be documented and reported, surely it would be of some interest to policymakers. Years of life lost to abortion generate a huge financial number as one calculates monetary consequences of years of productive life lost.  Not reporting the abortion statistics may have significant social consequences. The ostrich approach to this undeniable
Reflex suppression of renin secretion during distention of cardiopulmonary receptors in dogs.
Authors: J EZehr, J AHasbargen, K DKurz
Journal: Circulation Research (1976)

We studied the effect of brief periods of left atrial-pulmonary vein distention on the rate of renin secretion in sodium-restricted dogs anesthetized with chloralose and breathing spontaneously. Series 1 consisted of 32 trials in seven dogs with intact renal nerves and intact vagi. Renin secretion, calculated as the product of renal venous minus arterial renin activity (radioimmunoassay) times renal plasma flow (electromagnetic flowmeter), was depressed to 56% of control during atrial distention despite no change in arterial pressure, central venous pressure, or renal blood flow. Series 2 consisted of 58 trials in 12 dogs which had undergone unilateral renal denervation several days prior to the studies. Simultaneous, bilateral determinations indicated that renin secretion from the innervated kidney was depressed to 58% of control during atrial distention; secretion from the denervated kidney was unchanged. Series 3 consisted of 30 trials in six dogs with bilateral cervical vagotomy. Atrial distention evo...
Regulation of cardiac beta-adrenergic receptors by captopril. Implications for congestive heart failure.
Authors: A SMaisel, CPhillips, M CMichel, M GZiegler, S MCarter
Journal: Circulation (1989)

The interaction of the renin-angiotensin system and the sympathetic nervous system in patients with congestive heart failure is not well understood. We tested the hypothesis that angiotensin-converting enzyme inhibitors can resensitize the beta-adrenergic receptor system. Guinea pigs were given captopril, isoproterenol, or both for 2 weeks. At death, cardiac sarcolemmal and light vesicle fractions and intact mononuclear leukocytes were prepared. Captopril treatment led to an up-regulation of cardiac beta 1- but not mononuclear leukocyte beta 2-adrenergic receptors and an increase in isoproterenol-stimulated adenylate cyclase activity in the heart. Animals treated with isoproterenol developed cardiac hypertrophy, had increased plasma norepinephrine levels, and had a decreased number and responsiveness of both cardiac and mononuclear leukocyte beta-adrenergic receptors. Concomitant treatment with captopril attenuated alterations of heart weight, plasma norepinephrine levels, and cardiac beta-receptor densit...