tbuckley/cabot-search huggingface dataset:
Beta 1- and beta 2-adrenergic-receptor subpopulations in nonfailing and failing human ventricular myocardium: coupling of both receptor subtypes to muscle contraction and selective beta 1-receptor down-regulation in heart failure.
Authors: M RBristow, RGinsburg, VUmans, MFowler, WMinobe, RRasmussen, PZera, RMenlove, PShah, SJamieson
Journal: Circulation Research (1986)

We used radioligand binding techniques and measurement of beta-agonist-mediated positive inotropic responses in isolated cardiac tissue to examine beta-adrenergic-receptor subpopulations in nonfailing and failing human left and right ventricular myocardium. In tissue derived from 48 human hearts the receptor subtypes identified in nonfailing ventricle by radioligand binding were beta 1 (77%) and beta 2 (23%), with no evidence of an atypical beta-adrenergic receptor. In failing left ventricle the beta 1:beta 2 ratio was markedly different, i.e., 60:38. This decrease in the beta 1 proportion and increase in the beta 2 proportion in the failing ventricles were due to a 62%, selective down-regulation of the beta 1 subpopulation, with little or no change in beta 2 receptors. In muscle bath experiments in isolated trabeculae derived from nonfailing and failing right ventricles, both beta 1- and beta 2-adrenergic receptors were coupled to a positive inotropic response. In nonfailing myocardium, beta 1 respon...
Post-covid syndrome in individuals admitted to hospital with covid-19: retrospective cohort study
Authors: Daniel Ayoubkhani, Kamlesh Khunti, Vahé Nafilyan, Thomas Maddox, Ben Humberstone, Ian Diamond, Amitava Banerjee
Journal: BMJ (2021)

Abstract Objective To quantify rates of organ specific dysfunction in individuals with covid-19 after discharge from hospital compared with a matched control group from the general population. Design Retrospective cohort study. Setting NHS hospitals in England. Participants 47 780 individuals (mean age 65, 55% men) in hospital with covid-19 and discharged alive by 31 August 2020, exactly matched to controls from a pool of about 50 million people in England for personal and clinical characteristics from 10 years of electronic health records. Main outcome measures Rates of hospital readmission (or any admission for controls), all cause mortality, and diagnoses of respiratory, cardiovascular, metabolic, kidney, and liver diseases until 30 September 2020. Variations in rate ratios by age, sex, and ethnicity. Results Over a mean follow-up of 140 days, nearly a third of individuals who were discharged from hospital after acute covid-19 were readmitted (14 060 of 47 780) and more than 1 in 10 (5875) died after discharge, with these events occurring at rates four and eight times greater, respectively, than in the matched control group. Rates of respiratory disease (P&lt;0.001), diabetes (P&lt;0.001), and cardiovascular disease (P&lt;0.001) were also significantly raised in patients with covid-19, with 770 (95% confidence interval 758 to 783), 127 (122 to 132), and 126 (121 to 131) diagnoses per 1000 person years, respectively. Rate ratios were greater for individuals aged less than 70 than for those aged 70 or older, and in ethnic minority groups compared with the white population, with the largest differences seen for respiratory disease (10.5 (95% confidence interval 9.7 to 11.4) for age less than 70 years v 4.6 (4.3 to 4.8) for age ≥70, and 11.4 (9.8 to 13.3) for non-white v 5.2 (5.0 to 5.5) for white individuals). Conclusions Individuals discharged from hospital after covid-19 had increased rates of multiorgan dysfunction compared with the expected risk in the general population. The increase in risk was not confined to the elderly and was not uniform across ethnicities. The diagnosis, treatment, and prevention of post-covid syndrome requires integrated rather than organ or disease specific approaches, and urgent research is needed to establish the risk factors.
Myocardial contrast echocardiography: a reproducible technique of myocardial opacification for identifying regional perfusion deficits.
Authors: CTei, TSakamaki, P MShah, SMeerbaum, KShimoura, SKondo, ECorday
Journal: Circulation (1983)

The effects and reliability of a simple method of contrast two-dimensional echocardiographic delineation of myocardium after intracoronary injections were evaluated in closed-chest dogs. Multiple injections of an agitated saline-Renografin (meglumine diatrizoate) mixture (3:2 ratio, 2-ml bolus) into the left main coronary artery as well as at different sites of the left anterior descending and circumflex coronary arteries were studied in several short-axis and long-axis cross sections of the left ventricle. These contrast injections opacified specific regions of left ventricular myocardium depending on the site of injection. Contrast injection into the left main coronary artery provided a clear, echo-free outline (negative contrast) of underperfused myocardium distal to the coronary occlusion. Reproducibility studies of the extent of involved zones measured in echocardiographic cross sections indicated high intra- and interobserver correlation coefficients (r = 0.97 and 0.97). The effects of the intracoro...
Thromboxane B2 in cardiac lymph. Effect of superoxide dismutase and catalase during myocardial ischemia and reperfusion.
Authors: L HMichael, ZZhang, C JHartley, RBolli, A ATaylor, M LEntman
Journal: Circulation Research (1990)

Neutrophils have been implicated in the genesis of myocardial ischemia-reperfusion injury, and their mechanism of action has been linked to the production of reactive oxygen species, fatty acid-derived prostanoids, and leukotrienes. In this study, we examined the potential relation between production of reactive oxygen species and cyclooxygenase-derived autacoids by studying the effects of superoxide dismutase (SOD) and catalase (CAT) on the rise in thromboxane formation observed with myocardial ischemia and reperfusion. Immunoreactive thromboxane B2 was measured in cardiac lymph from conscious dogs during reperfusion after a 60-minute occlusion in the presence of infusions of SOD alone, CAT alone, and a combination of SOD and CAT. Reperfusion after 60 minutes of ischemia causes an immediate elevation in thromboxane B2. SOD and CAT infusion prevented this rise in thromboxane B2 as did infusion of SOD alone. The ability of SOD-CAT to suppress thromboxane B2 production dissipated within 3 hours after the ce...
Carotid arteriosclerosis in identical twins discordant for cigarette smoking.
Authors: AHaapanen, MKoskenvuo, JKaprio, Y AKesäniemi, KHeikkilä
Journal: Circulation (1989)

From a nationwide twin panel, identical twin pairs with highest discordance in cigarette smoking were selected for a study of arteriosclerosis (49 pairs with a mean age of 52 years). Smoking history was obtained in 1975, 1981, and 1986. The mean life-long smoking dose of the smoking cotwins was 20 package-years. The smoking and nonsmoking cotwins had similar systolic and diastolic blood pressures, total plasma cholesterol level, body mass index, and some psychosocial factors; the only difference was found in use of alcohol, which was greater among smoking cotwins. Duplex sonography of carotid arteries was performed. Carotid artery stenoses (narrowing of area of the lumen with 15-60%) were found in nine pairs: in nine smoking twins and in two of their nonsmoking cotwins (p = 0.036). The total area of carotid plaques was 3.2 times larger in smoking cotwins (p less than 0.001). The thickness of the inner layer of carotid arteries was more marked in smoking cotwins (p less than 0.001). The size of plaques and...
Sustained ventricular tachycardia in patients with idiopathic dilated cardiomyopathy: electrophysiologic testing and lack of response to antiarrhythmic drug therapy.
Authors: D SPoll, F EMarchlinski, A EBuxton, J UDoherty, H LWaxman, M EJosephson
Journal: Circulation (1984)

Eleven consecutive patients with idiopathic dilated cardiomyopathy and spontaneous, sustained ventricular tachycardia (VT) of uniform morphology underwent programmed ventricular stimulation and serial antiarrhythmic drug testing. The mean ejection fraction was 30 +/- 6.4%. Sustained VT was induced by programmed electrical stimulation in all 11 patients. A mean of 3.7 +/- 2.4 antiarrhythmic drugs were evaluated by programmed stimulation, including at least one experimental agent in eight patients. In nine of 11 patients VT remained inducible on all drug therapy. During a mean follow-up period of 21 +/- 14 months there were four sudden deaths and two patients with recurrences of VT. In all six patients with sudden death or recurrence of VT, the arrhythmia remained inducible on drug therapy. Three patients who died suddenly had a hemodynamically stable, induced tachycardia on antiarrhythmic therapy. Of eight patients treated with amiodarone, only two were successfully treated. We conclude that in patients wi...
Magnetically Controlled Capsule Endoscopy (MCCE) Improves Distal Esophageal Mucosal And Circumferential Z-Line Visibility
Authors: A Finta, M Szalai, BD Lovasz, K Helle, G Olle, A Rosztoczy, L Madacsy
Journal: Endoscopy (2021)

Aims Magnetically controlled capsule endoscopy (MCCE) provides the opportunity for the non-invasive endoscopic screening of the upper gastrointestinal tract before small bowel capsule endoscopy (SBCE). Our recent in-vitro study gave preliminary evidence for the optimal setting of the outer magnetic field of the Ankon MCCE system to enhance the visualization of the cardia. Therefore, we aimed to compare the in-vivo visibility of the distal esophagus and the Z-line by different capsule swallowing protocols.
Reassessing the Inclusion of Race in Diagnosing Kidney Diseases: An Interim Report from the NKF-ASN Task Force
Authors: Cynthia Delgado, Mukta Baweja, Nilka Ríos Burrows, Deidra C. Crews, Nwamaka D. Eneanya, Crystal A. Gadegbeku, Lesley A. Inker, Mallika L. Mendu, W. Greg Miller, Marva M. Moxey-Mims, Glenda V. Roberts, Wendy L. St. Peter, Curtis Warfield, Neil R. Powe
Journal: Journal of the American Society of Nephrology (2021)

For almost two decades, equations that use serum creatinine, age, sex, and race to eGFR have included “race” as Black or non-Black. Given considerable evidence of disparities in health and healthcare delivery in African American communities, some regard keeping a race term in GFR equations as a practice that differentially influences access to care and kidney transplantation. Others assert that race captures important non GFR determinants of serum creatinine and its removal from the calculation may perpetuate other disparities. The National Kidney Foundation (NKF) and American Society of Nephrology (ASN) established a task force in 2020 to reassess the inclusion of race in the estimation of GFR in the United States and its implications for diagnosis and subsequent management of patients with, or at risk for, kidney diseases. This interim report details the process, initial assessment of evidence, and values defined regarding the use of race to estimate GFR. We organized activities in phases: ( 1 ) clarify the problem and examine evidence, ( 2 ) evaluate different approaches to address use of race in GFR estimation, and ( 3 ) make recommendations. In phase one, we constructed statements about the evidence and defined values regarding equity and disparities; race and racism; GFR measurement, estimation, and equation performance; laboratory standardization; and patient perspectives. We also identified several approaches to estimate GFR and a set of attributes to evaluate these approaches. Building on evidence and values, the attributes of alternative approaches to estimate GFR will be evaluated in the next phases and recommendations will be made.
Anisotropy of water diffusion in the myocardium of the rat.
Authors: LGarrido, V JWedeen, K KKwong, U MSpencer, H LKantor
Journal: Circulation Research (1994)

Pulsed field gradient nuclear magnetic resonance methods combined with nuclear magnetic resonance imaging were used to determine the water diffusion anisotropy in perfused rat hearts at 37 degrees C. It was found that the observed diffusion coefficient D(app) (apparent diffusion coefficient) depends on the orientation of the applied gradient g. When g is parallel to the epicardial surface, the observed diffusivity is D(app) parallel = 1.8 +/- 0.4 x 10(-9) m2.s-1, whereas when g is perpendicular to it, diffusivity is D(app) perpendicular = 2.5 +/- 0.5 x 10(-9) m2.s-1. To better characterize this directional dependence, images of the second-order diffusion tensor D of the myocardium were obtained. These data demonstrate several essential features of cardiac myoarchitecture, including the helicity of fiber orientation with respect to the ventricular axis and the variation of fiber pitch angle with transmural depth. Diffusion anisotropy may be quantified in a coordinate-independent manner by the eigenvalues o...
Dose-dependent effect of aspirin on carotid atherosclerosis.
Authors: CRanke, HHecker, ACreutzig, KAlexander
Journal: Circulation (1993)

BACKGROUNDAntiplatelet treatment with aspirin is well established as secondary prophylaxis after a transient ischemic attack or minor ischemic stroke, but the effect of aspirin treatment on the course of carotid atherosclerosis is unknown. We investigated the effect of aspirin on the initial stages of carotid atherosclerosis.METHODS AND RESULTSPatients were recruited from a prospective, randomized, double-blind clinical trial to compare two doses of aspirin (900 mg versus 50 mg daily) with regard to restenoses after lower limb angioplasty. Of the 383 patients admitted to the angioplasty trial, 27 patients with 104 small carotid atheroma (< 50% lumen narrowing) were examined at entry and after 1 year of aspirin treatment with the use of a high-resolution ultrasound duplex system. Disease progression and regression were defined by a change of maximal plaque area (as measured by longitudinal ultrasound sections) of more than 2 SDs of the method. The change in plaque area was significantly different for the t...
Effects of chronic hypertension and sympathetic nerves on the cerebral microvasculature of stroke-prone spontaneously hypertensive rats.
Authors: A HWerber, D DHeistad
Journal: Circulation Research (1984)

The purpose of this study was to examine hemodynamic mechanisms which protect cerebral vessels against chronic hypertension, and contribute to protective effects of sympathetic nerves in the cerebral circulation. We studied stroke-prone spontaneously hypertensive rats and normotensive Wistar-Kyoto rats. At 3-4 weeks of age, all rats underwent removal of one superior cervical sympathetic ganglion. Approximately 1 year later, we cut the superior cervical sympathetic nerve contralateral to the chronic ganglionectomy and exposed pial arterioles on the cerebral cortex ipsilateral or contralateral to the chronic ganglionectomy. We measured aortic, pial arteriolar, and venous pressures with a servo-null technique, and cerebral blood flow with microspheres. Large artery resistance and small vessel resistance were calculated. During control conditions, pressure in pial arterioles was higher in stroke-prone spontaneously hypertensive rats (83 +/- 6 mm Hg) (mean +/- SE) than in Wistar-Kyoto rats (60 +/- 3 mm Hg, P l...
Arginine restores cholinergic relaxation of hypercholesterolemic rabbit thoracic aorta.
Authors: J PCooke, N AAndon, X JGirerd, A THirsch, M ACreager
Journal: Circulation (1991)

BACKGROUNDReduced synthesis of endothelium-derived relaxing factor (EDRF) may explain impaired endothelium-dependent vasodilation in hypercholesterolemia. Accordingly, we designed studies to determine if endothelium-dependent relaxation in hypercholesterolemic rabbits may be restored by supplying L-arginine, the precursor of EDRF.METHODS AND RESULTSNormal or hypercholesterolemic rabbits received intravenous L-arginine (10 mg/kg/min) or vehicle for 70 minutes. Subsequently, animals were killed, thoracic aortas were harvested, and vascular rings were studied in vitro. Rings were contracted by norepinephrine and relaxed by acetylcholine chloride or sodium nitroprusside. Vasorelaxation was quantified by determining the maximal response (expressed as percent relaxation of the contraction) and the ED50 (dose of drug inducing 50% relaxation; expressed as -log M). In vessels from hypercholesterolemic animals receiving vehicle, there was a fivefold rightward shift in sensitivity to acetylcholine compared with norm...
Therapy to reduce free radicals during early reperfusion does not limit the size of myocardial infarcts caused by 90 minutes of ischemia in dogs.
Authors: V JRichard, C EMurry, R BJennings, K AReimer
Journal: Circulation (1988)

It has been postulated that oxygen-centered free radicals are produced in significant quantities upon reperfusion of ischemic myocardium and could cause the death of myocytes that are still reversibly injured at the end of ischemia (reperfusion injury). However, we have shown previously that anti-free radical therapies including superoxide dismutase (SOD) and inhibitors of xanthine oxidase did not limit infarct size after 40 minutes of ischemia and 4 days of reperfusion in dogs. To test whether 40 minutes of ischemia is too brief a period to produce the prerequisite conditions for free radical-mediated necrosis upon reperfusion, we studied infarcts produced by 90 minutes of ischemia followed by reperfusion. Dogs in an SOD-catalase group received a 60-minute infusion of SOD (15,000 units/kg) and catalase (55,000 units/kg) beginning 25 minutes before and ending 35 minutes after reperfusion. A second group of dogs received a single injection of the xanthine oxidase inhibitor oxypurinol (20 mg/kg) 25 minute...
Quantitative Doppler assessment of valvular regurgitation.
Authors: MEnriquez-Sarano, K RBailey, J BSeward, A JTajik, M JKrohn, J MMays
Journal: Circulation (1993)

BACKGROUNDQuantitation of valvular regurgitation remains a challenge. The accuracy of quantitative Doppler is controversial, and its ability to measure regurgitant volume is unknown; therefore, it is not widely used.METHODS AND RESULTSIn 120 patients (20 without regurgitation, 19 with aortic regurgitation, and 81 with mitral regurgitation), the stroke volume through the mitral annulus and left ventricular outflow tract were measured using pulsed-wave Doppler concurrently with left ventricular stroke volume calculated using left ventricular volumes measured by two-dimensional echocardiography Simpson's biapical method. Regurgitant volume and fraction were thus computed using Doppler or ventricular methods. In normal patients there were good correlations between Doppler and left ventricular measurements of stroke volume. Doppler regurgitant volume and fraction were 4.4 +/- 4.4 mL and 5.3 +/- 4.5%, respectively. In patients with aortic regurgitation, there were good correlations between Doppler and left vent...
Torsades de pointes: electrophysiologic studies in patients without transient pharmacologic or metabolic abnormalities.
Authors: L NHorowitz, A MGreenspan, S RSpielman, M EJosephson
Journal: Circulation (1981)

Electrophysiologic studies were performed in 21 patients who had torsades de pointes. This ventricular tachyarrhythmia, characterized by rapid (200-250 beats/min) and irregular paroxysms and progressively varying QRS amplitude and polarity, occurred in the absence of electrolyte disturbance, antiarrhythmic drug therapy or acute ischemia. The QTc interval was prolonged in seven of 21 patients. Electrophysiologic study included ventricular pacing with the introduction of one to three extrastimuli and rapid ventricular pacing. The effect of i.v. procainamide or quinidine in these patients was also studied. Torsades de pointes was inducible n 19 of 21 patients. Induced episodes closely resembled spontaneous episodes. Torsades de pointes spontaneously progressed to ventricular tachycardia with a uniform morphology in three patients and to ventricular fibrillation in four. In eight patients, procainamide or quinidine converted torsades de pointes into typical reentrant ventricular tachycardia. Our data suggest ...
From the authors:
Authors: L. Didon, A. Roos, M. Nord
Journal: European Respiratory Journal (2010)

We would like to thank M. Filippone and co-workers for their comments regarding our paper, “Lung-specific inactivation of CCAAT/enhancer binding protein α causes a pathological pattern characteristic of COPD” 1. We share their concern regarding the lack of human studies addressing the adult phenotype of former bronchopulmonary dysplasia (BPD) patients, and hope to continue this discussion. M. Filippone and co-workers address the difference between “old” and “new” BPD phenotypes, which warrants further discussion with regards to the findings presented in our paper. …
Vagus nerve stimulation alters regional acetylcholine turnover in rat heart.
Authors: D DLund, R POda, B JPardini, P GSchmid
Journal: Circulation Research (1986)

The turnover of neurotransmitter is a direct measure of neuronal function, varying with the impulse activity of the nerve. It is not known if vagal stimulation increases acetylcholine release uniformly throughout the heart, or if modification of neural signals occurs between the vagal nerve trunks and postganglionic synaptic terminals. The rate constant of acetylcholine turnover was measured in conduction and contractile regions of heart by quantifying the incorporation of [3H]choline into acetylcholine after labeling of the blood choline pool in urethane-anesthetized rats during two levels of vagal activity. Choline and acetylcholine were assayed by high pressure liquid chromatography with electrochemical detection of post-column enzymic reaction product, peroxide. The specific activities of choline and acetylcholine in the tissues at sacrifice were used to calculate the fractional turnover rates in cardiac regions. Supramaximal bilateral vagal stimulation for 20 minutes decreased heart rate (P less than...
Effects of serotonin on intracellular pH and contraction in vascular smooth muscle.
Authors: A MKahn, MBishara, E JCragoe, J CAllen, C LSeidel, S SNavran, R GO'Neil, N AMcCarty, HShelat
Journal: Circulation Research (1992)

Serotonin (5-HT) and other contractile agonists stimulate Na(+)-H+ exchange in vascular smooth muscle. Since intracellular alkalinization, per se, stimulates contraction, we tested whether 5-HT-induced contraction was associated with an increased pHi. In HCO3(-)-free buffer (pHo 7.4), 5-HT (10(-5) M) increased pHi, as measured by 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein fluorescence, from 7.10 +/- 0.03 to 7.34 +/- 0.03 (p < 0.01) in primary cultures of canine femoral artery vascular smooth muscle cells grown to confluence in the presence of 10% fetal calf serum. In HCO3- buffer (24 mM, pHo 7.4), resting pHi was 7.26 +/- 0.04 (p < 0.01 versus HCO3(-)-free buffer) but was not altered by 5-HT. In both types of buffer, 5-HT stimulated 5-(N-ethyl-N-isopropyl)amiloride-sensitive 22Na+ uptake (Na(+)-H+ exchange). In HCO3- buffer and in Na(+)- and HCO3(-)-free buffer, 5-HT increased 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid-sensitive 36Cl- uptake, suggesting that 5-HT stimulated Na(+)-independent ...
Human plasmacytoid dendritic cells mount a distinct antiviral response to virus-infected cells
Authors: Tae Jin Yun, Suzu Igarashi, Haoquan Zhao, Oriana A. Perez, Marcus R. Pereira, Emmanuel Zorn, Yufeng Shen, Felicia Goodrum, Adeeb Rahman, Peter A. Sims, Donna L. Farber, Boris Reizis
Journal: Science Immunology (2021)

pDCs recognize cells infected with human cytomegalovirus and respond with a unique prolonged activation program.