tbuckley/cabot-search huggingface dataset:
Optical mapping of repolarization and refractoriness from intact hearts.
Authors: I REfimov, D THuang, J MRendt, GSalama
Journal: Circulation (1994)

BACKGROUNDHeterogeneities of repolarization (R) across the myocardium have been invoked to explain most reentrant arrhythmias. The measurement of refractory periods (RPs) has been widely used to assess R, but conventional electrode and extrastimulus mapping techniques have not provided reliable maps of RPs.METHODS AND RESULTSGuinea pig hearts were stained with a voltage-sensitive dye to measure fluorescence (F) action potentials (APs) from 124 sites with a photodiode array. AP duration (APD) was defined as the time between depolarization (dF/dt)max and R time points (ie, the time when AP returns to baseline or some percent thereof). However, R time points are difficult to determine because AP downstrokes are often encumbered by drifting baselines and motion artifacts, which make this definition ambiguous. In optical and microelectrode recordings, the second derivative of AP downstrokes is shown to contain an easily detected, unique local maximum. The correlation between the position of this maximum (d2F/d...
Differential effects of antihypertensive drug therapy on vascular smooth muscle cell hypertrophy, hyperploidy, and hyperplasia in the spontaneously hypertensive rat.
Authors: G KOwens
Journal: Circulation Research (1985)

The present report extends our previous studies of smooth muscle cell hypertrophy, hyperploidy, and hyperplasia in the 5-month-old spontaneously hypertensive and Wistar-Kyoto rats to include analyses of 3- and 7-month-old rats and explores the effects of antihypertensive drug treatment on the accelerated growth of vascular smooth muscle in aortas of spontaneously hypertensive vs. Wistar-Kyoto rats. Drug-treated rats were administered a combination of reserpine, hydralazine, and chlorathiazide in their drinking water, either between 3 and 5 months or between 5 and 7 months of age. Drug treatment decreased the blood pressure of spontaneously hypertensive rats to values at or below those of Wistar-Kyoto rats for both age-treatment groups. Smooth muscle growth was evaluated by morphometric analyses of aortic smooth muscle content, flow cytometric and microdensitometric measurements of the frequency of polyploid smooth muscle cells, biochemical estimates of aortic medial smooth muscle cell number, and microden...
A Pan-Histone Deacetylase Inhibitor Enhances the Antitumor Activity of B7-H3–Specific CAR T Cells in Solid Tumors
Authors: Xinyuan Lei, Zhanpeng Ou, Zhaohui Yang, Jianglong Zhong, Yanliang Zhu, Jing Tian, Jiannan Wu, Heran Deng, Xinyu Lin, Yu Peng, Bowen Li, Lile He, Zhiming Tu, Weixiong Chen, Qunxing Li, Niu Liu, Hanqing Zhang, Zhangsong Wang, Zezhen Fang, Teppei Yamada, Xiaobin Lv, Tian Tian, Guokai Pan, Fan Wu, Liping Xiao, Lizao Zhang, Tingting Cai, Xinhui Wang, Bakhos A. Tannous, Jinsong Li, Filippos Kontos, Soldano Ferrone, Song Fan
Journal: Clinical Cancer Research (2021)

The limited efficacy of chimeric antigen receptor (CAR) T-cell therapies with solid malignancies prompted us to test whether epigenetic therapy could enhance the antitumor activity of B7-H3.CAR T cells with several solid cancer types.We evaluated B7-H3 expression in many human solid cancer and normal tissue samples. The efficacy of the combinatorial therapy with B7-H3.CAR T cells and the deacetylase inhibitor SAHA with several solid cancer types and the potential underlying mechanisms were characterized with in vitro and ex vivo experiments.B7-H3 is expressed in most of the human solid tumor samples tested, but exhibits a restricted expression in normal tissues. B7-H3.CAR T cells selectively killed B7-H3 expressing human cancer cell lines in vitro. A low dose of SAHA upregulated B7-H3 expression in several types of solid cancer cells at the transcriptional level and B7-H3.CAR expression on human transgenic T-cell membrane. In contrast, the expression of immunosuppressive molecules, such as CTLA-4 and TET2, by T cells was downregulated upon SAHA treatment. A low dose of SAHA significantly enhanced the antitumor activity of B7-H3.CAR T cells with solid cancers in vitro and ex vivo, including orthotopic patient-derived xenograft and metastatic models treated with autologous CAR T-cell infusions.Our results show that our novel strategy which combines SAHA and B7-H3.CAR T cells enhances their therapeutic efficacy with solid cancers and justify its translation to a clinical setting.
Clinical use of sodium nitroprusside in chronic ischemic heart disease. Effects on peripheral vascular resistance and venous tone and on ventricular volume, pump and mechanical performance.
Authors: R RMiller, L AVismara, RZelis, E AAmsterdam, D TMason
Journal: Circulation (1975)

Although hemodynamic benefit has been shown with sodium nitroprusside (NP) in acute coronary pump failure, complete understanding of the mechanisms of action of the agent on the cardiocirculation and its value in chronic ventricular dysfunction are lacking. This investigation evaluates the effects of NP on the systemic and regional arterial and venous beds and on cardiac dynamics, ventricular volumes, contractile state and myocardial energetics in long-standing congestive heart failure. Twelve patients with chronic coronary pump dysfunction received NP infusion to lower systolic pressure to 95-105 mm Hg. Left ventricular (LV) function was assessed directly by angiographic volumes and high fidelity pressure, and peripheral circulatory dynamics were determined simultaneously by forearm arterial and venous plethysmography. NP reduced mean arterial pressure (MAP) from 88.2 to 73.4 mm Hg (P less than 0.05) and significantly (P less than 0.05) enhanced the variables of LV performance: LV end-diastolic pressure ...
Recruitment of an inotropic reserve in moderately ischemic myocardium at the expense of metabolic recovery. A model of short-term hibernation.
Authors: RSchulz, B DGuth, KPieper, CMartin, GHeusch
Journal: Circulation Research (1992)

The regional, functional as well as metabolic consequences of inotropic stimulation on myocardium subjected to prolonged moderate ischemia were investigated. In 35 enflurane-anesthetized swine the left anterior descending coronary artery was cannulated and perfused at constant flow. The vein paralleling the left anterior descending coronary artery was cannulated for measurement of lactate and oxygen content. Transmural biopsies from the anterior myocardium were taken for the measurement of ATP, creatine phosphate, and glycogen. After control measurements, flow was adjusted to reduce regional contractile function (expressed as a work index, determined by sonomicrometry) by approximately 50%. After either 5, 25, 40, or 85 minutes of moderate ischemia, dobutamine was infused for 5 minutes into the ischemic region. In a separate group of five swine also subjected to 85 minutes of ischemia followed by infusion of dobutamine and 2 hours of reperfusion, triphenyltetrazolium chloride staining and light microscopy...
Evaluation of the force-frequency relationship as a descriptor of the inotropic state of canine left ventricular myocardium.
Authors: P AAnderson, J SRankin, C EArentzen, R WAnderson, E AJohnson
Journal: Circulation Research (1976)

The short-term force-frequency characteristics of canine left ventricular myocardium were examined in both isolated and intact preparations by briefly pertubing the frequency of contraction with early extrasystoles. The maximum rate of rise of isometric tension (Fmas) of the isolated trabeculae carneae was potentiated by the introduction of extrasystoles. The ratio of Fmas of potentiated to control beats (force-frequency ratio) was not altered significantly by a change in muscle length. However, exposure of the trabeculae to isoproterenol (10(-7)M) significantly changed the force-frequency ratio obtained in response to a constant frequency perturbation. Similar experiments were performed on chronically instrumented conscious dogs. Left ventricular minor axis diameter was measured with implanted pulse-transit ultrasonic dimension transducers, and intracavitary pressure was measured with a high fidelity micromanometer. Atrial pacing was performed so that the end-diastolic diameters of the beats preceding an...
Platelet cyclic GMP. A potentially useful indicator to evaluate the effects of nitroglycerin and nitrate tolerance.
Authors: HWatanabe, MKakihana, SOhtsuka, TEnomoto, KYasui, YSugishita
Journal: Circulation (1993)

BACKGROUNDThe present study was designed to investigate the intracellular production of cyclic GMP (cGMP) in platelets in response to nitroglycerin and to determine the potential clinical value of platelet cGMP as an indicator of the effects of nitroglycerin and nitrate tolerance.METHODS AND RESULTSPlatelet cGMP levels and the diameters of the coronary arteries before and 2 minutes after intracoronary injection of 200 micrograms nitroglycerin were measured in 15 patients who had previously received nitrates (nitrates group) and in 16 who had not received any nitrates (no-nitrates group). Platelet cGMP levels increased significantly after nitroglycerin injection in the two groups, but plasma cGMP levels and plasma atrial natriuretic peptide levels did not change. The percent increase in platelet cGMP levels and the percent dilatation of the left anterior descending (LAD) and left circumflex (LCx) coronary arteries after nitroglycerin injection were higher in the no-nitrates group than in the nitrates group...
Disseminating Health Care Innovation
Authors: Dieter R Enzmann, James Sayre
Journal: JAMA (2003)

Our website uses cookies to enhance your experience. By continuing to use our site, or clicking "Continue," you are agreeing to our Cookie Policy | Continue JAMA HomeNew OnlineCurrent IssueFor Authors Publications JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry (1919-1959) Podcasts Clinical Reviews Editors' Summary Medical News Author Interviews More JN Learning / CMESubscribeJobsInstitutions / LibrariansReprints & Permissions Terms of Use | Privacy Policy | Accessibility Statement 2023 American Medical Association. All Rights Reserved Search All JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Forum Archive JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry Input Search Term Sign In Individual Sign In Sign inCreate an Account Access through your institution Sign In Purchase Options: Buy this article Rent this article Subscribe to the JAMA journal
Counter-regulatory responses to continuous and intermittent therapy with nitroglycerin.
Authors: J DParker, BFarrell, TFenton, MCohanim, J OParker
Journal: Circulation (1991)

BACKGROUNDVasodilator therapy may be associated with reflex counter-regulatory responses, and these responses may play a role in the development of tolerance to nitroglycerin (GTN).METHODS AND RESULTSStanding systolic blood pressure, body weight, urinary sodium, and hormonal responses to continuous (n = 10) and intermittent (n = 10) transdermal GTN administration were studied in normal volunteers. There was rapid attenuation of the hypotensive response to transdermal GTN therapy in the continuous but not in the intermittent therapy group. Significant weight gain and sodium retention occurred during continuous but not during intermittent GTN therapy. This was accompanied by a greater decrease in hematocrit in the continuous group, a finding that suggests that plasma volume expansion occurred during continuous GTN therapy. Continuous GTN therapy was associated with increases in plasma norepinephrine, atrial natriuretic peptide, arginine, vasopressin, and plasma renin activity. A different pattern of neuroho...
The relationship between overdrive suppression and overdrive excitation in ventricular pacemakers in dogs.
Authors: MVassalle, MCummins, CCastro, J HStuckey
Journal: Circulation Research (1976)

We studied the excitatory and inhibitory effects of overdrive on idioventricular pacemakers in anesthetized dogs with recently induced complete atrioventricular block. The following results were obtained: (1) a slow driving rate may induce a temporary rhythm which may be reinstituted with additional stimuli; (2) the induced rhythm may appear as coupled extrasystoles which, on interruption of the drive, are found to be self-sustaining; (3) during continued slow driving, extrasystoles may appear and disappear in a cyclical manner; (4) a short period of fast driving may be followed by a fast new rhythm, the rate and duration of which are a function of the rate and duration of drive; (5) fast driving may induce a new rhythm at a rate below predrive control; (6) after a long period fast driving, only suppression follows; and (7) intermittent periods of fast driving lead to a summation of inhibition with each successive period. These results suggest the following conclusions: (1) under certain conditions, elect...
Endothelial expression of thrombomodulin is reversibly regulated by fluid shear stress.
Authors: A MMalek, RJackman, R DRosenberg, SIzumo
Journal: Circulation Research (1994)

The vascular endothelium, by virtue of its position at the interface between blood and the vessel wall, is known to play a critical role in the control of thrombosis and fibrinolysis. Thrombomodulin (TM) is a surface receptor that binds thrombin and is a potent activator of the protein C anticoagulant pathway. Although TM expression is known to be regulated by various cytokines, little is known about its response to ever-present biomechanical stimuli. We have explored the role of fluid shear stress, imparted on the luminal surface of the endothelial cell as a result of blood flow, on the expression of TM mRNA and protein in both bovine aortic endothelial (BAE) and bovine smooth muscle (BSM) cells in an in vitro system. We report in the present study that TM expression is regulated by flow. Subjecting BAE cells to fluid shear stress in the physiological range of magnitude of 15 (moderate shear stress) and 36 (elevated shear stress) dynes/cm2 resulted in a mild transient increase followed by a significant d...
Upper limit of vulnerability reliably predicts the defibrillation threshold in humans.
Authors: CHwang, C DSwerdlow, R MKass, E SGang, W JMandel, C TPeter, P SChen
Journal: Circulation (1994)

BACKGROUNDThe upper limit of vulnerability is the stimulus strength above which electrical stimulation cannot induce ventricular fibrillation even when the stimulus occurs during the vulnerable period of the cardiac cycle. The purpose of this study was to test the hypothesis that the upper limit of vulnerability can accurately predict the defibrillation threshold in patients undergoing implantable cardioverter-defibrillator (ICD) implantation using nonthoracotomy lead systems.METHODS AND RESULTSWe studied 77 patients at the time of ICD implantation. Multiple endocardial-endocardial and endocardial-subcutaneous shock pathways were used. Two different protocols were used to test the upper limit of vulnerability. In protocol 1 (n = 17), the upper limit of vulnerability was tested with two shocks on the peak or the up-slope of the T wave of paced rhythm. The shocks were given randomly either at the peak and 20 milliseconds before the peak of T wave (n = 7) or at 20 and 40 milliseconds before the peak of T wav...
Effect of acute volume load on refractoriness and arrhythmia development in isolated, chronically infarcted canine hearts.
Authors: HCalkins, W LMaughan, H FWeisman, SSugiura, KSagawa, J HLevine
Journal: Circulation (1989)

In normal isolated, perfused canine ventricles, increased ventricular volume leads to shortening of refractoriness. To test the hypothesis that myocardium within an infarction zone is more susceptible to volume-induced changes in refractoriness than is normal myocardium, we measured strength-interval curves at low and high end-diastolic volumes at control and infarcted sites in 14 isolated, blood perfused, canine hearts with chronic (greater than 25 days) infarctions. In addition, the effect of volume load on inducing ventricular arrhythmias was studied at one to six sites in 11 hearts. Differences in refractoriness and inducibility at low (22 +/- 5 ml) and high (48 +/- 6 ml) end-diastolic volumes were compared. At control sites, volume load reduced the absolute refractory period from 178 +/- 16.5 to 175 +/- 16.7 msec (p less than 0.05), but no significant change in the relative refractory period occurred. At infarcted sites, the change in refractoriness with volume load was greater, and the absolute refr...
DCM, MR, af tachy の薬物治療抵抗性心不全に Maze+MVR+TAP+両心室ペーシングによる再同期療法を行った一治験例
Authors: 押富隆, 毅文 丁, 一樹 佐藤, 崇 三浦, 栄市 丁
Journal: Circulation (2004)
Isolation and characterization of single canine cardiac purkinje cells.
Authors: M FSheets, C TJanuary, H AFozzard
Journal: Circulation Research (1983)

Single cardiac Purkinje cells should permit improved control of membrane potential during voltage clamp studies. We have developed a method for isolation of single canine Purkinje cells and studied their basic electrophysiological properties using conventional single and double microelectrode techniques. The single Purkinje cells appeared free of connective tissue, had regular striations, excluded trypan blue vital stain, and remained quiescent in solutions containing 1.8 mM calcium. Electrophysiological studies at 22 degrees C showed normal resting membrane potentials, and action potentials could be elicited by extracellular or intracellular stimulation. Plot of the upstroke velocity of the action potential (Vmax) vs. the holding potential showed a sigmoid curve with the peak mean Vmax of 167 V/sec, and voltage corresponding to half-maximal Vmax was about -70 mV. Plot of the overshoot of the action potential vs. the holding potential was similar, with maximal values of about +30 mV. The mean membrane inp...
Noninvasive evaluation of regional myocardial perfusion in 112 patients using a mobile scintillation camera and intravenous nitrogen-13 labeled ammonia.
Journal: Circulation (1976)

The short half-life positron emitter 13N, as labeled ammonia (13NH4+), was evaluated as a myocardial imaging agent. Regional myocardial uptake of 13NH4 correlated with the distribution of labeled microspheres in experimental myocardial infarction. Using intravenous 13NH4+, myocardial scintigraphy was performed in 85 cardiac patients and 27 normal subjects. Ninety-five scintigrams were suitable for analysis. Eighteen of 24 normal subjects had homogeneous myocardial images; six had inhomogeneous images attributable to early technical problems. Perfusion defects were observed in the scintigrams of 82% (57/65) of patients with coronary artery disease, being most common in patients with myocardial infarction (27/28). Six sequential studies showed changes in perfusion consistent with the clinical course of each patient. Scintigraphic abnormalities were also observed in 4/6 patients with valvular heart disease. 13NH4+ myocardial scintigraphy is a valid and sensitive method of assessing regional myocardial perfus...
Eleven worthy aims for clinical leadership of health system reform
Authors: D. M. Berwick
Journal: JAMA (1994)

Clinicians ought to be playing a central role in making the changes in the health care system that will allow the system to offer better outcomes, greater ease of use, lower cost, and more social justice in health status. Instead, most of the proposed changes that are today called "health care reform" are actually changes in the surroundings of care rather than changes in the care itself. Clinicians have an opportunity to exercise leadership for the improvement of care, but they must first agree to address the aims of reform and to adopt an agenda of specific changes in their own work that are likely to meet the social needs driving the reform movement. Health services research offers a sound scientific basis for identifying promising improvement aims for clinician-led reform. Eleven plausible aims are these: (1) reducing inappropriate surgery, hospital admissions, and diagnostic tests; (2) reducing key underlying root causes of illness (especially smoking, handgun violence, preventable childhood injuries, and alcohol and cocaine abuse); (3) reducing cesarean section rates to pre-1980 levels; (4) reducing the use of unwanted medical procedures at the end of life; (5) simplifying pharmaceutical use, especially for antibiotics and medication of the elderly; (6) increasing active patient participation in therapeutic decision making; (7) decreasing waiting times in health care settings; (8) reducing inventory levels in health care organizations; (9) recording only useful information only once; (10) consolidating and reducing the total supply of high-technology medical and surgical care; and (11) reducing the racial gap in infant mortality and low birth weight. Health care professions and their professional organizations in concert should embrace these 11 aims, establish measurements of progress toward them, and commit to continuous and fundamental changes in their pursuit. (<i>JAMA</i>. 1994;272:797-802)
98O First-line nivolumab (NIVO) + ipilimumab (IPI) + 2 cycles chemotherapy (chemo) vs 4 cycles chemo in advanced non-small cell lung cancer (aNSCLC): Association of blood and tissue tumor mutational burden (TMB) with efficacy in CheckMate 9LA
Authors: L. Paz-Ares, T-E. Ciuleanu, M. Cobo, M. Schenker, B. Zurawski, J. Menezes, E. Richardet, J. Bennouna, E. Felip, O. Juan-Vidal, A. Alexandru, H. Sakai, A. Scherpereel, M. Reck, S. Lu, T. John, S. Meadows-Shropshire, D. Balli, S. Agrawal, D.P. Carbone
Journal: Journal of Thoracic Oncology (2021)
Description of Restrictively Defined Acute Flaccid Myelitis
Authors: José Berciano, Daniel Natera-de Benito
Journal: JAMA Pediatrics (2019)

Our website uses cookies to enhance your experience. By continuing to use our site, or clicking "Continue," you are agreeing to our Cookie Policy | Continue JAMA Pediatrics HomeNew OnlineCurrent IssueFor Authors Podcast Publications JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry (1919-1959) JN Learning / CMESubscribeJobsInstitutions / LibrariansReprints & Permissions Terms of Use | Privacy Policy | Accessibility Statement 2023 American Medical Association. All Rights Reserved Search All JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Forum Archive JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry Input Search Term Sign In Individual Sign In Sign inCreate an Account Access through your institution Sign In Purchase Options: Buy this article Rent this article Subscribe to the JAMA Pediatrics journal
Selinexor Maintenance Is Feasible and Tolerable after Allogeneic Stem Cell Transplant (allo-SCT) for Patients with Acute Myeloid Leukemia (AML) and Myelodysplastic Syndrome (MDS)
Authors: Hongtao Liu, Andrew Artz, Richard A. Larson, Satyajit Kosuri, Wendy Stock, Michael R. Bishop
Journal: Blood (2017)