tbuckley/cabot-search huggingface dataset:
Local administration of porcine immunomodulatory, chemotactic and angiogenic extracellular vesicles using engineered cardiac scaffolds for myocardial infarction
Authors: Marta Monguió-Tortajada, Cristina Prat-Vidal, Miriam Moron-Font, Marta Clos-Sansalvador, Alexandra Calle, Paloma Gastelurrutia, Adriana Cserkoova, Anna Morancho, Miguel Ángel Ramírez, Anna Rosell, Antoni Bayes-Genis, Carolina Gálvez-Montón, Francesc E. Borràs, Santiago Roura
Journal: Bioactive Materials (2021)

The administration of extracellular vesicles (EV) from mesenchymal stromal cells (MSC) is a promising cell-free nanotherapy for tissue repair after myocardial infarction (MI). However, the optimal EV delivery strategy remains undetermined. Here, we designed a novel MSC-EV delivery, using 3D scaffolds engineered from decellularised cardiac tissue as a cell-free product for cardiac repair. EV from porcine cardiac adipose tissue-derived MSC (cATMSC) were purified by size exclusion chromatography (SEC), functionally analysed and loaded to scaffolds. cATMSC-EV markedly reduced polyclonal proliferation and pro-inflammatory cytokines production (IFNγ, TNFα, IL12p40) of allogeneic PBMC. Moreover, cATMSC-EV recruited outgrowth endothelial cells (OEC) and allogeneic MSC, and promoted angiogenesis. Fluorescently labelled cATMSC-EV were mixed with peptide hydrogel, and were successfully retained in decellularised scaffolds. Then, cATMSC-EV-embedded pericardial scaffolds were administered in vivo over the ischemic myocardium in a pig model of MI. Six days from implantation, the engineered scaffold efficiently integrated into the post-infarcted myocardium. cATMSC-EV were detected within the construct and MI core, and promoted an increase in vascular density and reduction in macrophage and T cell infiltration within the damaged myocardium. The confined administration of multifunctional MSC-EV within an engineered pericardial scaffold ensures local EV dosage and release, and generates a vascularised bioactive niche for cell recruitment, engraftment and modulation of short-term post-ischemic inflammation.
Current pharmacologic treatment of elevated serum cholesterol.
Authors: M JTikkanen, E ANikkilä
Journal: Circulation (1987)

A basic difference between dietary and drug therapy of hypercholesterolemia is that dietary therapy can be used as part of a population strategy, whereas the decision to use drugs is always made on an individual basis. In each case, the decision to treat must be based on the assumption that more good than harm is caused to the patient. This is a difficult situation for the physician. As long as there is no easy way of assessing the state and rate of progression of coronary lesions, the physician must treat the patient on statistical grounds only, i.e., rely on the results of studies showing that lowering serum cholesterol significantly decreases the risk of coronary events. Such evidence has recently been strengthened, which increases motivation for both physician and patients. The current general opinion is that drug therapy must be generally confined to those at high risk, i.e., patients with severe hypercholesterolemia. For individuals with moderately elevated serum cholesterol levels, dietary advice a...
Ventricular interaction during experimental acute pulmonary embolism.
Authors: IBelenkie, RDani, E RSmith, J VTyberg
Journal: Circulation (1988)

Although stroke volume may decrease markedly after acute pulmonary embolism, left ventricular end-diastolic pressure (LVEDP) usually changes very little, which suggests that compliance or contractility or both are reduced. To test the hypothesis that the altered LV function during pulmonary embolism is primarily due to reduced preload mediated by increased pericardial constraint, hemodynamics and chamber dimensions (measured by sonomicrometry) were assessed in seven anesthetized dogs during control volume loading, after pulmonary embolism (with autologous blood clot), and after repeated pulmonary embolism in the volume-loaded state. The correlation between LVEDP and an index of LVED volume (LVED area index) throughout a wide range of LVEDP before and after embolism was poor (mean r = 0.42; range, 0-0.82). However, the correlation between transmural LVEDP (LVEDP-directly measured pericardial pressure) and LVED area index (mean r = 0.78; range, 0.61-0.94) was significantly higher (p = 0.03). Similarly, an i...
Quantitative analysis of right and left ventricular infarction in the presence of postinfarction ventricular septal defect.
Authors: R GCummings, K AReimer, RCaliff, DHackel, JBoswick, J ELowe
Journal: Circulation (1988)

To quantitate the amount of right and left ventricular infarction in patients dying with postinfarction ventricular septal defect (PIVSD), hearts from 54 patients with anterior or inferior myocardial infarction were studied at autopsy. Fifteen hearts had myocardial infarction with PIVSD and 39 hearts had infarction without PIVSD and were used as a comparison group. All infarcts were sized histologically and the percent of each ventricle infarcted was quantitated by computer-assisted planimetry. The pathologic substrate for PIVSD was diffuse coronary artery disease with acute thrombosis resulting in transmural confluent infarction. Within the PIVSD group, there was significantly more left ventricle involved in anterior infarctions than in inferior infarctions (p less than .04). Conversely, there was more right ventricular infarction in inferiorly located myocardial infarctions with resulting PIVSD (p = .059). When infarctions resulting in PIVSD were compared with infarctions not resulting in PIVSD, the PIV...
Subaortic obstruction after the use of an intracardiac baffle to tunnel the left ventricle to the aorta.
Authors: A PRocchini, ARosenthal, A RCastaneda, J FKeane, RJeresaty
Journal: Circulation (1976)

Postoperative hemodynamic studies in five patients document subaortic obstruction after surgical repair utilizing an intracardiac baffle to establish continuity between the left ventricle and the aorta. Four of the patients had a Rastelli procedure for D-transposition of the great arteries with a ventricular septal defect and pulmonary stenosis; one patient had repair of double outlet right ventricle with a ventricular septal defect and pulmonary stenosis. The left ventricular outflow was shown to be a long narrow tunnel by angiography in four of five patients and by echocardiography in one patient. Resting aortic peak systolic pressure gradient ranged from 10 to 42 mm Hg (mean 24). The obstruction was localized to the proximal end of the left ventricule to aorta tunnel (i.e., at the site of ventricular septal defect) in five patients. One patient with a gradient of 42 mm Hg has angina and decreased exercise tolerance. Subaortic obstruction is a newly described sequelae after the Rastelli procedure for tr...
Bridging the digital divide: The use of text message-enabled video in the public safety-net setting
Authors: Abigail Cline, Carey Kim, Juliana Berk-Krauss, Abrahem Kazemi, David Ginsberg, Carlos J. Sarriera-Lazaro, Yasaman Mansouri, Bijan Safai, Ashley Keyes Jacobs, Shoshana Marmon
Journal: Journal of the American Academy of Dermatology (2021)
Modification by prostaglandins E1 and E2, indomethacin, and arachidonic acid of the vasoconstrictor responses of the isolated perfused rabbit and rat mesenteric arteries to adrenergic stimuli.
Authors: K UMalik, PRyan, J CMcGiff
Journal: Circulation Research (1976)

In isolated perfused rabbit mesenteric arteries, prostaglandin (PG) E1 and E2, 1-5NG/ML, did not alter the basal perfusion pressure, but reduced the vasoconstrictor responses to sympathetic nerve stimulation; the responses to injected norepinephrine were reduced by PGE1 and variably affected by PGE2. In contrast, in rat mesenteric arteries PGE1 and PGE2, 1-5 ng/ml, potentiated the vasoconstrictor responses to nerve stimulation and to injected norepinephrine. In rabbit mesenteric arteries, the inhibitor of PG synthesis, indomethacin, augmented the responses to sympathetic nerve stimulation and to injected norepinephrine, whereas in rat mesenteric arteries indomethacin inhibited the responses to both adrenergic stimuli. Arachidonic acid, a PG precursor, reduced the vasoconstrictor responses to sympathetic nerve stimulation and to injected norepinephrine in rabbit, whereas in rat, potentiation of the responses to adrenergic stimuli occurred. Since these effects of arachidonic acid were abolished by the simul...
Mitral valve prolapse: a consistent manifestation of type IV Ehlers-Danlos syndrome. The pathogenetic role of the abnormal production of type III collagen.
Authors: A SJaffe, E MGeltman, G ERodey, JUitto
Journal: Circulation (1981)

To evaluate whether abnormal production of type III collagen, the characteristic biochemical feature of patients with the type IV Ehlers-Danlos syndrome, consistently predisposes to mitral valve prolapse, we evaluated the family of a proband with classic type IV Ehlers-Danlos syndrome. Production of type III collagen was assessed with the use of cultured skin fibroblasts. Mitral valve prolapse was detected by M-mode and two-dimensional echocardiography. Biochemical abnormalities in the production of type III collagen and echocardiographic findings of mitral valve prolapse were completely concordant. All patients with abnormal production of type III collagen had mitral valve prolapse and all subjects with normal production of type III collagen had entirely normal echocardiograms. Six of the eight patients with abnormal production of type III collagen had subtle cutaneous abnormalities. The consistent association of abnormal production of type III collagen and mitral valve prolapse in this family suggests t...
A new method for quantification of regurgitant flow rate using color Doppler flow imaging of the flow convergence region proximal to a discrete orifice. An in vitro study.
Authors: FRecusani, G SBargiggia, A PYoganathan, ARaisaro, L MValdes-Cruz, H WSung, CBertucci, MGallati, V AMoises, I ASimpson
Journal: Circulation (1991)

While color Doppler flow mapping has yielded a quick and relatively sensitive method for visualizing the turbulent jets generated in valvular insufficiency, quantification of the degree of valvular insufficiency has been limited by the dependence of visualization of turbulent jets on hemodynamic as well as instrument-related factors. Color Doppler flow imaging, however, does have the capability of reliably showing the spatial relations of laminar flows. An area where flow accelerates proximal to a regurgitant orifice is commonly visualized on the left ventricular side of a mitral regurgitant orifice, especially when imaging is performed with high gain and a low pulse repetition frequency. This area of flow convergence, where the flow stream narrows symmetrically, can be quantified because velocity and the flow cross-sectional area change in inverse proportion along streamlines centered at the orifice. In this study, a gravity-driven constant-flow system with five sharp-edged diaphragm orifices (ranging fr...
Increased thromboxane biosynthesis during coronary thrombolysis. Evidence that platelet activation and thromboxane A2 modulate the response to tissue-type plasminogen activator in vivo.
Authors: D JFitzgerald, FWright, G AFitzGerald
Journal: Circulation Research (1989)

Platelet activation is markedly increased during coronary thrombolysis and limits the response to thrombolytic therapy. A possible mediator of platelet activation in this setting is thromboxane (TX) A2, a potent platelet agonist formed in greatly increased amounts during coronary thrombolysis in man. To address this hypothesis, we examined the role of TXA2 in modulating the response to intravenous tissue-type plasminogen activator (t-PA) in a chronic canine model of coronary thrombosis. Reperfusion occurred in 60 +/- 5 minutes and was complicated by spontaneous reocclusion. The times to reperfusion and reocclusion were platelet-dependent. Consistent with a role for TXA2 in this process, TXA2 biosynthesis, determined a excretion of its enzymatic metabolite, 2,3-dinor-TXB2, was markedly increased during coronary thrombolysis. Furthermore, inhibition of TXA2 by aspirin, given alone or in combination with a TXA2/prostaglandin endoperoxide receptor antagonist, accelerated reperfusion and partly inhibited cycli...
Paradoxical effects of exercise on the QT interval in patients with polymorphic ventricular tachycardia receiving type Ia antiarrhythmic agents.
Authors: A HKadish, H FWeisman, E PVeltri, A EEpstein, M JSlepian, J HLevine
Journal: Circulation (1990)

We analyzed the results of exercise testing performed in the absence of all antiarrhythmic drugs in 11 case patients with newly documented polymorphic ventricular tachycardia in response to type Ia antiarrhythmic agents. These results were compared with those found in 11 control patients matched for age, sex, and heart disease to determine whether the response of the QT interval to exercise testing was abnormal in patients who developed worsening of arrhythmia while taking antiarrhythmic drugs. QT, RR, and QTc intervals (by Bazett's method) were evaluated at rest and at 3 minutes of exercise in both groups. At rest, there was no significant difference in the QT interval (410 +/- 13 vs. 386 +/- 11 msec), RR interval (890 +/- 56 vs. 781 +/- 43 msec), or corrected QT interval (438 +/- 10 vs. 438 +/- 4 msec) in the case patients and the control patients. Both groups demonstrated a similar chronotropic response to exercise. The QT interval shortened in both groups with exercise (p less than 0.001), but the deg...
The hemodynamic effects of cardiac tamponade: mainly the result of atrial, not ventricular, compression.
Authors: N OFowler, MGabel
Journal: Circulation (1985)

We studied the hemodynamic effects of surgically induced regional cardiac tamponade in anesthetized dogs. Tamponade restricted to either the right or the left ventricle was compared with tamponade of either ventricle and both atria. Intrapericardial pressures were elevated to approximately 20 mm Hg. With tamponade of the right ventricle alone, aortic pressure rose from 161 +/- 3.8 to 164 +/- 3.4 mm Hg (p greater than .05) and cardiac output fell from 149.4 +/- 16.1 to 134.9 +/- 11.9 ml/kg/min (p greater than .05). However, tamponade of the right ventricle plus both atria decreased mean aortic pressure from 152.5 +/- 3.6 to 115.9 +/- 8.7 mm Hg (p less than .01) and cardiac output fell from 118 +/- 14.8 to 38.9 +/- 4.8 ml/kg/min (p less than .01). With tamponade of the left ventricle alone, aortic mean pressure changed significantly from 158.5 +/- 6.1 (control) to 148.9 +/- 5.0 mm Hg (tamponade) (p less than .05) and cardiac output was 135.5 +/- 28.3 (control) and 111 +/- 24.7 ml/kg/min (tamponade) (p great...
Evidence for sensory nerve involvement in cutaneous reactive hyperemia in humans.
Authors: S WLarkin, T JWilliams
Journal: Circulation Research (1993)

To study the involvement of local sensory nerves in reactive hyperemia, laser-Doppler measurements of skin blood flow were recorded in locally anesthetized and untreated forearm sites in eight volunteers after 90, 180, and 360 seconds of arrested forearm blood flow. The reactive hyperemia increased in magnitude and duration in response to increasing occlusion periods. However, maximum postocclusion flows in the untreated site of 31 +/- 5%, 38 +/- 6%, and 49 +/- 5% (mean +/- SEM) flux were significantly greater than the 14 +/- 3% (P < .005), 20 +/- 4% (P < .005), and 25 +/- 5% (P < .001) flux seen in the anesthetized sites. The duration of the hyperemia was also shortened from 139 +/- 26 seconds in the untreated site to 61 +/- 17 seconds (after the 360-second occlusion, P < .02) in the anesthetized sites. The anesthesia did not alter the increase in local blood flow induced by intradermally injected calcitonin gene-related peptide. Topically applied capsaicin induced a localized increase in blood flow that...
Verapamil-induced improvement in left ventricular diastolic filling and increased exercise tolerance in patients with hypertrophic cardiomyopathy: short- and long-term effects.
Authors: R OBonow, VDilsizian, D RRosing, B JMaron, S LBacharach, M VGreen
Journal: Circulation (1985)

Verapamil improves exercise tolerance and decreases symptoms in many patients with hypertrophic cardiomyopathy. The mechanisms responsible for these effects are not completely understood, although previous studies indicate that verapamil enhances left ventricular relaxation and diastolic filling in such patients. To investigate the association between changes in left ventricular filling and exercise tolerance after verapamil, we studied 55 patients with hypertrophic cardiomyopathy by radionuclide angiography and graded treadmill testing before and after 1 to 4 weeks of therapy with orally administered verapamil, 320 to 640 mg/d. The verapamil-induced increase in peak left ventricular filling rate at rest (from 3.1 +/- 1.3 to 3.7 +/- 1.3 end-diastolic volumes/sec; p less than .001) was associated with an increase in exercise tolerance (from 5.9 +/- 3.6 to 8.7 +/- 4.7 min; p less than .001); exercise capacity increased in 34 of 43 patients (79%) manifesting an increase in peak filling rate but only one of 1...
Right and left ventricular function after cardiac transplantation. Changes during and after rejection.
Authors: E WSkowronski, MEpstein, DOta, P MHoagland, J BGordon, R MAdamson, MMcDaniel, K LPeterson, S CSmith, B EJaski
Journal: Circulation (1991)

BACKGROUNDAttempts to identify noninvasive markers of ventricular dysfunction accompanying acute rejection have been hampered by a lack of detailed simultaneous hemodynamic data. Therefore, we prospectively performed serial monitoring of detailed left and right heart hemodynamic parameters in cardiac transplant recipients at the time of routine endomyocardial biopsy to better define the physiology of the allograft heart during and after acute rejection.METHODS AND RESULTSTo better assess the pathophysiology of the rejection process, 18 cardiac transplant patients were prospectively studied by serial right heart micromanometer catheterization and digital image processing at the time of routine endomyocardial biopsy. Eleven patients had 18 episodes of rejection. Studies of baseline (negative biopsy preceding rejection), rejection (acute moderate rejection), and resolved (first negative biopsy after rejection) states were compared. Seven patients who did not experience an episode of rejection served as the c...
L-arginine evokes both endothelium-dependent and -independent relaxations in L-arginine-depleted aortas of the rat.
Authors: V BSchini, P MVanhoutte
Journal: Circulation Research (1991)

This study was designed to investigate the effects of L-arginine (the substrate for the formation of endothelium-derived nitric oxide) in vascular tissues. Rat aortic rings, with or without endothelium, were suspended in organ chambers for the measurement of isometric tension; they were contracted with phenylephrine (10(-6) M). After a short incubation period (0.5 hour) in physiological salt solution, L-arginine induced minor changes in both types of rings. In contrast, when the incubation time was increased (2, 4, 6, and 8 hours), L-arginine evoked concentration- and time-dependent relaxations in aortic rings both with and without endothelium. The relaxations were larger in rings with endothelium. The presence of L-arginine (10(-3) M) in the incubation medium inhibited subsequent relaxations evoked by the amino acid. The concentration-relaxation curves associated with acetylcholine in rings with endothelium and the curves associated with Sin-1, a spontaneous donor of nitric oxide, in rings with or withou...
Origin of epicardial ST-T wave potentials in the intact dog.
Authors: M SSpach, R CBarr
Journal: Circulation Research (1976)

Ventricular repolarization was analyzed by measuring epicardial potential distributions in intact dogs with single or multiple ectopic foci and a minimum at the terminal site(s) of excitation. During the latter half of the T wave the distributions became more complex, and two maxima evolved from the initial one at each ectopic site. The measured epicardial potentials were simulated by means of a model of ST-T wave events that is suitable for study of single and multiple ectopic beats with fusion, a a model we call 'SI model.' Intracellular potentials around the ventricles during repolarization were calculated from measured excitation sequences and known action potential shapes. The extracellular potentials around the ventricles were computed from the intracellular ones by a simplified ventricular geometry. The satisfactory agreement between the theoretical and measured extracellular potential distribution shows that the complex changes which occur throughout the ST-T wave are predicted well on the basis o...
Amiloride delays the ischemia-induced rise in cytosolic free calcium.
Authors: EMurphy, MPerlman, R ELondon, CSteenbergen
Journal: Circulation Research (1991)

An increase in cytosolic free calcium (Cai) has been shown to occur early during ischemia in perfused rat, ferret, and rabbit hearts. It has been proposed that this increase in Cai may occur as a result of exchange of Nai for Cao, which occurs as a result of an increase in Nai arising from exchange of Nao for H+i. The latter exchange is stimulated by the intracellular acidification that occurs during ischemia. To test this hypothesis, we examined Cai, Nai, ATP, and pHi during ischemia in rats in the presence and absence of 1 mM amiloride, a Na-H exchange inhibitor. Cai was measured using 19F nuclear magnetic resonance (NMR) of 1,2-bis(2-amino-5-fluorophenoxy)ethane-N,N,N',N'-tetra-acetic acid (5F-BAPTA)-loaded rat hearts. Nai was measured using 23Na NMR, and the shift reagent 1,4,7,10-tetraazacyclododecane-N,N',N,N'-tetramethylenephosph onate (Tm[DOTP]-5) was used to separate Nai and Nao. ATP and pH were determined from 31P NMR measurements. During 20 minutes of ischemia, amiloride did not significantly...
A study of comparative blood pressure measures in predicting risk of coronary heart disease.
Authors: R HRosenman, R ISholtz, R JBrand
Journal: Circulation (1976)

The Western Collaborative Group Study is a prospective study of 3,154 employed men, aged 39-59 years. Coronary heart disease (CHD) occurred in 257 subjects during 8.5 years of follow-up. The multiple logistic risk model was used to assess the comparative strength of systolic, diastolic, mean arterial and pulse pressure for the prediction of CHD in two age decades after adjustment for age, serum cholesterol, cigarette smoking, behavior pattern and weight. The risk of CHD was more strongly associated with the systolic than the diastolic pressure. The general practice of assessing the importance of blood pressure based only on the diastolic component should be reassessed.
Don't look now
Authors: L. Farrell
Journal: BMJ (1996)

In Ireland we have a thing called “craic.” It is a bit hard to define; loosely, it means having fun with friends, with the preferred, though optional, elements of wild music and what Sean Thornton would have called “black beers.” It classically, therefore, occurs in a public house, but really it can happen anywhere: on a Sunday morning out for a walk, during lunch at work, at a funeral, or a-sitting on a gate watching the world go by.

The one constant factor is that it must be spontaneous; planned craic is a dead duck. You may assemble all the desirable ingredients—Friday night after …