tbuckley/cabot-search huggingface dataset:
Endothelin ETA receptor antagonist blocks cardiac hypertrophy provoked by hemodynamic overload.
Authors: HIto, MHiroe, YHirata, HFujisaki, SAdachi, HAkimoto, YOhta, FMarumo
Journal: Circulation (1994)

BACKGROUNDWe have recently shown that angiotensin II-induced hypertrophy of cultured rat cardiomyocytes was partially blocked by an endothelin (ET) receptor antagonist (BQ123) selective for the ETA subtype, suggesting the possible involvement of endogenous ET-1 in the mechanism of cardiac hypertrophy in vitro. In the present study, we studied the in vivo blockade effects of BQ123 on cardiac hypertrophy provoked by left ventricular overload with aortic banding in adult rats.METHODS AND RESULTSForty rats were divided into four groups: (1) sham-operated rats without BQ123 administration, (2) rats with aortic banding without BQ123 administration, (3) sham-operated rats with BQ123 administration, and (4) rats with aortic banding with BQ123 administration. BQ123 (250 micrograms/h) was administered continuously by an osmotic pump starting 24 hours before operation. BQ123 blocked increases in the ratio of left ventricular weight to body weight and in the diameter of cardiomyocytes provoked by aortic banding at 1 ...
Case 10-2021: A 70-Year-Old Man with Depressed Mood, Unsteady Gait, and Urinary Incontinence
Authors: Feyza Marouf, McKinley Glover, Bryce Wininger, William T. Curry
Journal: New England Journal of Medicine (2021)

A 70-year-old man with bipolar disorder was evaluated because of depressed mood, suicidal ideation, and gait disturbance. One month earlier, he had been voluntarily hospitalized for depression. In the following weeks, he had worsening gait instability and urinary incontinence. Diagnostic tests were performed.
Electrocardiographic precordial mapping in anterior myocardial infarction. The critical period for interventions as exemplified by methylprednisolone.
Authors: A PSelwyn, K MFox, EWelman, AJonathan, J PShillingford
Journal: Circulation (1978)

Serial 72-point precordial mapping of ECG has been recorded to describe the natural history of changes in the precordial areas of ST segment elevation and the development of Q waves in 51 patients with acute uncomplicated anterior myocardial infarction. Eight patients have been studied in the same way but received 25 mg/kg of methylprednisolone sodium succinate as a single intravenous injection within 6 hours from the onset of chest pain. There was a linear relationship between the stable precordial area of Q waves at 24 hours and the rapidly changing precordial areas of ST segment elevation at 2--3 hours, 5--6 hours and 12 hours after the onset of pain in the untreated patients. When methylprednisolone was given, the treated patients developed a smaller precordial area of Q waves at 24 hours than was predicted from the precordial area of ST elevation recorded before the drug was given. This study has introduced a technique that can provide a qualitative assessment of the relationship between ECG evidence...
Serial evaluation of myocardial thickening and thinning in acute experimental infarction: identification and quantification using two-dimensional echocardiography.
Authors: MNieminen, A FParisi, J EO'Boyle, E DFolland, SKhuri, R AKloner
Journal: Circulation (1982)

Regional left ventricular function was studied serially by quantitative two-dimensional echocardiography (2-D echo) in 20 dogs after left anterior descending coronary artery ligation. Normal values for regional myocardial thickening were established in 20 healthy dogs and used as a standard to recognize abnormally contracting segments (ACS). In normal hearts, the mean percent thickening tended to increase from base (25.8%) to apex (34.0%), but showed considerable diversity from segment to segment (range 20.0-40.0%); nevertheless, at least some degree of thickening was seen in every segment. After coronary occlusion, myocardial segments either thinned or failed to thicken. At the papillary muscle level, there was an improvement in function between 2 and 48 hours, with thinning at 2 hours and thickening at 48 hours. Tissue infarct size (IS) determined at 48 hours was related to IS derived from a weighted summation of ACS at 2, 24 and 48 hours. At 2 hours, ACS considerably overpredicted and correlated poorly...
Effect of edema on segmental vascular resistance in isolated lamb lungs determined by micropuncture.
Authors: J URaj, PChen
Journal: Circulation Research (1987)

We have studied the mechanical effects of fluid accumulation on the pulmonary vasculature in 28 isolated blood perfused lungs of newborn lambs. Vascular resistance in the pulmonary arteries, microvessels, and veins was determined by micropuncture measurement of microvascular pressures, and regional distribution of blood flow in the lungs was determined using radiolabelled microspheres both before and after the development of varying degrees of hydrostatic edema. Edema was induced by raising venous pressure. During measurements, alveolar and venous pressures were kept constant at 7 and 8 cm H2O, respectively, as well as lung blood flow (540 +/- 107 ml/min). All vascular pressures were referenced to the superior surface of the lung, site of all micropunctures. Active vasomotor changes were eliminated by addition of papaverine to the perfusate. Under baseline nonedematous conditions in the absence of vasomotor tone, 17% of the total pressure drop was in arteries, 41% was in microvessels, and 42% was in veins...
Echocardiography in Wolff-Parkinson-White syndrome.
Authors: M SChandra, R EKerber, D DBrown, D CFunk
Journal: Circulation (1976)

Twenty-six patients with Wolff-Parkinson-White (WPW) syndrome were studied by echocardiography. They were classified into the following WPW types: anterior right ventricular pre-excitation (Type I) - six patients; posterior right ventricular pre-excitation (Type II) - six patients; posterior left ventricular pre-excitation (Type III) - fourteen patients. Twenty-three patients were in WPW at the time of study. Four patients with Type I WPW had abnormal systolic motion of the interventricular septum: three paradoxical and one flat. Patients with Type II and Type III WPW had no septal motion abnormalities related to pre-excitation. Three patients had intermittent WPW, Type III; in all three only minor changes in normal septal motion were apparent on WPW beats. Associated cardiac abnormalities were evident in six patients: two mitral prolapse (one Type II WPS and one Tpe III); one idiopathic hypertrophic subaortic stenosis (Type III); one congestive cardiomyopathy (Type III); one hypertrophic nonobstructive c...
Reactive dilation of large coronary arteries in conscious dogs.
Authors: T HHintze, S FVatner
Journal: Circulation Research (1984)

To study the response of large coronary arteries to short periods of myocardial ischemia a pair of ultrasonic dimension transducers, a flow probe and a hydraulic occluder were implanted around the left circumflex coronary artery for the instantaneous and continuous measurement of external coronary artery dimensions and coronary blood flow, respectively. At 6.1 +/- 0.4 seconds after release of a 15-second occlusion, mean coronary blood flow increased by 255 +/- 30% from a preocclusion flow of 32 +/- 4.1 ml/min. At this time, large coronary arterial cross-sectional area was unchanged but increased slowly, reaching a peak 28 +/- 4.4% above preocclusion levels 61 +/- 3.2 seconds after occlusion, i.e., reactive dilation. During maximal reactive dilation, coronary blood flow had already returned to control levels, and heart rate, mean arterial pressure, left ventricular systolic pressure, and left ventricular dP/dt were not different from control. The reactive dilation was not affected if the occlusion occurred...
FANCD2 and HES1 Synergistically Regulate the Immunometabolism of Hematopoietic Stem Cells through Transcriptional Suppression of <i>Pparg-</i> mediated Fatty Acid Oxidation and Oxidative Phosphorylation
Authors: Limei Wu, Jian Xu, Ingrid Weterrins, Peter Mathers, Wei Du
Journal: Blood (2017)
Modulation of cellular calcium stores in the perfused rat heart by isoproterenol and ryanodine.
Authors: D RHunter, R AHaworth, H ABerkoff
Journal: Circulation Research (1983)

The inhibitory action of procaine on cellular calcium release was utilized to define a new cellular calcium pool which, under physiological conditions, is present only during catecholamine stimulation. Rat hearts labeled with 45Ca++ were perfused with medium containing procaine and EGTA at 23 degrees C to remove extracellular calcium, and then cellular calcium was released by removal of procaine and restoration of calcium. By this method we have identified a cellular calcium pool (pool C) whose release is inhibited by procaine, but which does not require extracellular calcium for its release. Release of pool C can also be triggered by caffeine. [We have previously identified a cellular calcium pool (pool A) whose release is triggered by caffeine, inhibited by procaine, and which does require extracellular calcium for its release.] When hearts were labeled for 3 minutes with perfusate containing 1 mM 45Ca++, 48 +/- 6 nmol Ca++/g wet weight was found in pool A, but only 3 +/- 1 nmol Ca++/g in pool C. Howeve...
Federated deep learning for detecting COVID-19 lung abnormalities in CT: a privacy-preserving multinational validation study
Authors: Qi Dou, Tiffany Y. So, Meirui Jiang, Quande Liu, Varut Vardhanabhuti, Georgios Kaissis, Zeju Li, Weixin Si, Heather H. C. Lee, Kevin Yu, Zuxin Feng, Li Dong, Egon Burian, Friederike Jungmann, Rickmer Braren, Marcus Makowski, Bernhard Kainz, Daniel Rueckert, Ben Glocker, Simon C. H. Yu, Pheng Ann Heng
Journal: npj Digital Medicine (2021)

Data privacy mechanisms are essential for rapidly scaling medical training databases to capture the heterogeneity of patient data distributions toward robust and generalizable machine learning systems. In the current COVID-19 pandemic, a major focus of artificial intelligence (AI) is interpreting chest CT, which can be readily used in the assessment and management of the disease. This paper demonstrates the feasibility of a federated learning method for detecting COVID-19 related CT abnormalities with external validation on patients from a multinational study. We recruited 132 patients from seven multinational different centers, with three internal hospitals from Hong Kong for training and testing, and four external, independent datasets from Mainland China and Germany, for validating model generalizability. We also conducted case studies on longitudinal scans for automated estimation of lesion burden for hospitalized COVID-19 patients. We explore the federated learning algorithms to develop a privacy-preserving AI model for COVID-19 medical image diagnosis with good generalization capability on unseen multinational datasets. Federated learning could provide an effective mechanism during pandemics to rapidly develop clinically useful AI across institutions and countries overcoming the burden of central aggregation of large amounts of sensitive data.
LincRNA-p21 Regulates Neointima Formation, Vascular Smooth Muscle Cell Proliferation, Apoptosis, and Atherosclerosis by Enhancing p53 Activity
Authors: GengzeWu, JinCai, YuHan, JinghaiChen, Zhan-PengHuang, CaiyuChen, YueCai, HefeiHuang, YujiaYang, YukaiLiu, ZaichengXu, DuofenHe, XiaoqunZhang, XiaoyunHu, LucaPinello, DanZhong, FengtianHe, Guo-ChengYuan, Da-ZhiWang, ChunyuZeng
Journal: Circulation (2014)

Background—Long noncoding RNAs (lncRNAs) have recently been implicated in many biological processes and diseases. Atherosclerosis is a major risk factor for cardiovascular disease. However, the functional role of lncRNAs in atherosclerosis is largely unknown. Methods and Results—We identified lincRNA-p21 as a key regulator of cell proliferation and apoptosis during atherosclerosis. The expression of lincRNA-p21 was dramatically downregulated in atherosclerotic plaques of ApoE−/− mice, an animal model for atherosclerosis. Through loss- and gain-of-function approaches, we showed that lincRNA-p21 represses cell proliferation and induces apoptosis in vascular smooth muscle cells and mouse mononuclear macrophage cells in vitro. Moreover, we found that inhibition of lincRNA-p21 results in neointimal hyperplasia in vivo in a carotid artery injury model. Genome-wide analysis revealed that lincRNA-p21 inhibition dysregulated many p53 targets. Furthermore, lincRNA-p21, a transcriptional target of p53, feeds back to...
Ventricular arrhythmias in the late hospital phase of acute myocardial infarction. Relation to left ventricular function detected by gated cardiac blood pool scanning.
Authors: R ASchulze, JRouleau, PRigo, SBowers, H WStrauss, BPitt
Journal: Circulation (1975)

Abnormalities of left ventricular function and extent of myocardial infarction were studied in relation to prevalence of late ventricular premature contractions (VPCs) in 36 patients in the convalescent stage of acute myocardial infarction (MI). Left ventricular ejection fraction (EF) and percent akinesis (%A) were calculated from gated cardiac blood pool scans; myocardial infarct size was estimated from peak CPK values; and VPCs were detected by 24 hour ambulatory ECGs 2-4 weeks following hospitalization for acute MI. Twenty-two patients had either zero (class 0) or less than 30/hour unifocal VPCs (class I). Fourteen patients had greater than 30/hour unifocal (class II), multifocal (class III) or coupled VPCs (class IV), including ventricular tachycardia. Thirteen of 14 class II-IV patients had EF less than 40% compared with only 8 of 22 class 0-I patients. Class II-IV patients had significantly lower mean EF (30.5 +/- 2.3 SE to 49.6 +/- 4.0) P less than 0.01, higher mean %A (28.1 +/- 2.2 to 16.9 +/- 3.7...
The Role of the Intestinal Microbiota in the Carcinogenesis of Colorectal Cancer
Authors: I Karasev, V Vereshchak, T Davydkina, O Malikhova
Journal: Endoscopy (2021)

Aims There is growing evidence that the gut microbiota is one of the leading factors associated with colorectal cancer carcinogenesis. Etiological factors of CRC, in addition to genetic mutations, chronic inflammation, and exposure to carcinogens, include epigenetic imbalance, dietary changes, and immune system dysfunction. In recent years, there have been more and more studies on the pathogenesis of CRC based on microbiota.
A predictive method for estimating the late angiographic results of coronary intervention despite incomplete ascertainment.
Authors: R EKuntz, K MKeaney, CSenerchia, D SBaim
Journal: Circulation (1993)

BACKGROUNDInvestigations of coronary restenosis typically use late (4-6-month) angiographic end points. Since only 50-80% of patients generally undergo repeat angiography, however, restenosis for the population as a whole is usually estimated by assuming that nonrestudied and restudied patients are similar. If restudied and nonrestudied patients differ, incomplete angiographic follow-up can yield an erroneous estimate of restenosis. No suitable method has yet been devised to detect and correct these errors.METHODS AND RESULTSWe studied the clinical indications for angiographic restudy in an actual series of 301 treated lesions in 267 consecutive patients who underwent either Palmaz-Schatz stenting (126 patients) or directional coronary atherectomy (141 patients) at our institution. While only 249 (83%) treated segments underwent 4-6-month angiographic follow-up, all had clinical follow-up that described whether specific indications for restudy were present. Patients who had no clinical indications for suc...
Epicardial excitation during ventricular pacing. Relative independence of breakthrough sites from excitation sequence in canine right ventricle.
Authors: GArisi, EMacchi, CCorradi, R LLux, BTaccardi
Journal: Circulation Research (1992)

In a previous investigation, epicardial recordings with 1,124 closely spaced electrodes revealed 20-35 breakthrough (BKT) sites and an equal number of separate wave fronts on the ventricular surface of exposed dog hearts during normal sinus rhythm. In the present study we tried 1) to determine whether ventricular pacing also produced multiple BKTs and wave fronts and 2) to determine whether the number and location of BKTs were, to some degree, independent of pacing site. The study mainly focused on right ventricular BKTs observed during right ventricular pacing. To test hypotheses 1 and 2 we identified many breakthrough sites during sinus rhythm in seven exposed dog hearts and then paced the heart from several BKT and non-BKT sites on the right ventricle. Epicardial potential maps and excitation time maps were obtained by using 1,124 epicardial electrodes covering the anterior right ventricle and part of the anterior left ventricle. A primary wave front spread radially for several centimeters from the pac...
Is Artifical Intelligence (CAD EYE) Useful to Not Only Detect But Also to Characterize Small Colorectal Polyps? First Results From a Prospective French Multicenter Study
Authors: E Coron, G Vanbiervliet, V Prouvost, C Medlej, N Musquer, M Le Rhun, G Perrod, G Rahmi
Journal: Endoscopy (2021)

Aims ”Resect and discard” strategies are difficult to implement since optical diagnosis is challenging. Our aim was to assess the feasibility and performances of a new commercially available system for colorectal polyps.
Effects of acidosis on ventricular muscle from adult and neonatal rats.
Authors: R JSolaro, J ALee, J CKentish, D GAllen
Journal: Circulation Research (1988)

We compared the response of ventricular muscle from adult and neonatal rats to hypercapnic acidosis. In adult muscle, acidosis caused an initial rapid fall of developed tension to 30 +/- 5% of control (mean +/- SEM, n = 6). However, tension recovered slowly to a steady state that was 56 +/- 6% of control. In neonatal muscle, acidosis caused a significantly smaller initial fall in tension to 43 +/- 3% (n = 8, p less than 0.05), but the tension then showed a subsequent slower fall to a steady state that was 29 +/- 4% of control, significantly less than in the adult (p less than 0.01). We have attempted to identify the mechanisms underlying these differences in response. In detergent-skinned myofibrils, reducing the pH from 7.0 to 6.5 caused a reduction in the pCa50 of 0.61 units in the adult muscle, but only 0.27 units in the neonatal ventricular muscle. Myofibrillar Ca2+ sensitivity in neonatal ventricular muscle is thus less susceptible to the effects of acidic pH than that of adult muscle. Since intracel...
Endogenous nitric oxide protects against platelet aggregation and cyclic flow variations in stenosed and endothelium-injured arteries.
Authors: S KYao, J COber, AKrishnaswami, J JFerguson, H VAnderson, PGolino, L MBuja, J TWillerson
Journal: Circulation (1992)

BACKGROUNDThis study was designed to test the hypothesis that endogenously produced nitric oxide protects against platelet aggregation and cyclic flow variations in stenosed and endothelium-injured arteries of mongrel dogs.METHODS AND RESULTSNG-Monomethyl-L-arginine (L-NMMA), an inhibitor of nitric oxide formation, was administered at 5 mg/kg to 15 dogs after the left anterior descending coronary artery was mechanically injured and narrowed by external constrictors and to nine dogs before endothelial injury of the femoral artery and after injury and moderate arterial constriction. Treatment with L-NMMA resulted in cyclic flow variations (as detected by external Doppler flow probes) in the left anterior descending artery of seven of 15 dogs and in the femoral artery of four of nine dogs after endothelial injury. L-Arginine, the precursor for nitric oxide synthesis, was administered at 60 mg/kg and abolished cyclic flow variations in each of the 11 dogs. D-Arginine did not change the L-NMMA-induced cyclic f...
NG-nitro L-arginine methyl ester and other alkyl esters of arginine are muscarinic receptor antagonists.
Authors: I LBuxton, D JCheek, DEckman, D PWestfall, K MSanders, K DKeef
Journal: Circulation Research (1993)

Analogues of L-arginine with modifications at the terminal guanidino nitrogen and/or the carboxyl terminus of the molecule have been widely used for their ability to inhibit the production of nitric oxide and are thought to be competitive antagonists of nitric oxide synthase. The present studies were designed to test the possibility that these agents are also muscarinic receptor antagonists. Acetylcholine produced concentration-dependent contraction of endothelium-denuded rabbit coronary artery as well as isolated strips of canine colonic smooth muscle. The arginine analogue NG-nitro L-arginine methyl ester (L-NAME, 100 microM) but not NG-monomethyl L-arginine (L-NMMA, 100 microM) significantly shifted these contractile relations to the right, an effect that was not reversed by addition of 1 mM L-arginine. In radioligand binding studies using the muscarinic radioligand [3H]quinuclidinyl benzilate and tissues known to contain differing contributions of M1, M2, and M3 muscarinic receptors, addition of incre...
Magnetic resonance imaging of the iliofemoral arteries after balloon dilation angioplasty of aortic arch obstructions in children.
Authors: P EBurrows, L NBenson, PBabyn, CMacDonald
Journal: Circulation (1994)

BACKGROUNDWe wished to determine the nature and incidence of changes in the iliofemoral arteries after balloon dilation angioplasty (BDA) for aortic arch obstruction in children and to determine the reliability of gradient magnetic resonance imaging (MRI) in their detection.METHODS AND RESULTSSixty-three children, including 62 with and 1 without arch obstruction, underwent MRI of the iliofemoral vessels. Of these, 36 patients had undergone transfemoral BDA (7 after previous transfemoral diagnostic catheterization), 12 had undergone diagnostic transfemoral catheterization but not BDA, and 15 had no history of femoral arterial catheterization. The iliofemoral arteries were normal on MRI in all 15 children without catheterization. Among the 36 children who had undergone BDA, the ipsilateral iliofemoral artery was normal in 15, mildly narrowing in 7, and severely stenotic or occluded in 14 (39%), including 6 of 9 patients treated for acute femoral artery thrombosis and 8 with no history of femoral artery thro...
CBFβ-SMMHC Inhibition Disrupts Enhancer Chromatin Dynamics and Represses MYC Transcriptional Program in Inv(16) Leukemia
Authors: John Anto Pulikkan, Mahesh Hegde, Houda Belaghzal, Anuradha Illendula, Jun Yu, Hafiz Ahmed, Kelsey O'Hagen, Jianhong Ou, Carsten Müller-Tidow, Scot A. Wolfe, Julie Zhu, Job Dekker, John H. Bushweller, Lucio H. Castilla
Journal: Blood (2017)
The renal, forearm, and hormonal responses to standing in the presence and absence of propranolol.
Authors: G LBakris, D MWilson, J CBurnett
Journal: Circulation (1986)

Nine normal volunteers underwent assessment of renal, forearm, and hormonal responses to orthostasis (quiet standing) in the presence and absence of 1 week of oral propranolol (160 mg/day). This was done to test the hypothesis that physiologic decrements in renal function (glomerular filtration rate, effective renal plasma flow, and absolute urinary sodium excretion) are attenuated by propranolol during quiet standing. The present studies, however, demonstrate that propranolol exaggerates the physiologic decrement in glomerular filtration rate, effective renal plasma flow, and absolute urinary sodium excretion during orthostasis. Forearm and renal vascular resistances were also accentuated in the presence of propranolol during quiet standing. These responses were associated with significant increases in plasma norepinephrine. We conclude that long-term administration of propranolol accentuates the physiologic decrement in renal hemodynamic and excretory function as well as in the forearm hemodynamic respo...