tbuckley/cabot-search huggingface dataset:
Actions of lidocaine on transmembrane potentials of subendocardial Purkinje fibers surviving in infarcted canine hearts.
Authors: J DAllen, F JBrennan, A LWit
Journal: Circulation Research (1978)

We compared the effects of lidocaine, 2 X 10(-5) M, on transmembrane resting and action potentials of Purkinje fibers on the endocardial surface of 24- to 72-hour-old myocardial infarcts in dogs with its actions and subendocardial Purkinje fibers in normal hearts. At both proximal (near the tip of the papillary muscle) and distal (toward the apex) recording sites in noninfarcted hearts, lidocaine had no significant effect on maximum diastolic potential (MDP) or Vmax. It shortened action potential duration (APD) only at the proximal site. In infarcted hearts, we arbitrarily divided Purkinje fibers at the infarcted distal site into two groups. Group I consisted of fibers which did not have a severely depressed MDP or Vmax but in which APD was markedly prolonged. Lidocaine had no effect on MDP of these fibers, significantly depressed Vmax, and shortened APD. Group II consisted of fibers in which MDP and Vmax were markedly reduced. Lidocaine also reduced Vmax of these fibers further (by 60%) without altering ...
Preterm Birth and Heart Failure in Infancy and Beyond
Authors: Mandy Brown Belfort, Suzanne Brown Sacks
Journal: JAMA Pediatrics (2021)

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
Dependence of Gorlin formula and continuity equation valve areas on transvalvular volume flow rate in valvular aortic stenosis.
Authors: I GBurwash, D DThomas, MSadahiro, A SPearlman, E DVerrier, RThomas, C DKraft, C MOtto
Journal: Circulation (1994)

BACKGROUNDValve areas derived by the Gorlin formula have been observed to vary with transvalvular volume flow rate. Continuity equation valve areas calculated from Doppler-echo data have become a widely used alternate index of stenosis severity, but it is unclear whether continuity equation valve areas also vary with volume flow rate. This study was designed to investigate the effects of changing transvalvular volume flow rate on aortic valve areas calculated using both the Gorlin formula and the continuity equation in a model of chronic valvular aortic stenosis.METHODS AND RESULTSUsing a canine model of chronic valvular aortic stenosis in which anatomy and hemodynamics are similar to those of degenerative aortic stenosis, each subject (n = 8) underwent three studies at 2-week intervals. In each study, transvalvular volume flow rates were altered with saline or dobutamine infusion (mean, 10.3 +/- 5.1 flow rates per study). Simultaneous measurements were made of hemodynamics using micromanometer-tipped cat...
The subendocardial border zone during acute ischemia of the rabbit heart: an electrophysiologic, metabolic, and morphologic correlative study.
Authors: R LWilensky, JTranum-Jensen, RCoronel, A AWilde, J WFiolet, M JJanse
Journal: Circulation (1986)

Isolated preparations of rabbit interventricular septum were perfused through the coronary arteries with oxygenated Tyrode's solution and placed in a tissue bath where they were superfused as well. Transmembrane potentials were simultaneously recorded from the subendocardium with two flexibly mounted microelectrodes, one from a superficial cell, and the other from a deep cell. Ischemia was produced by stopping coronary flow while superfusion with oxygenated Tyrode's solution was maintained. After a 7 to 12 min ischemic period, the preparation was fixed by coronary perfusion with fixative while the microelectrodes remained in place. After fixation, the microelectrodes were withdrawn. Appropriate tissue blocks were cut in 4 micron serial sections and the microelectrode track was followed until the tip position was identified. Transmembrane potentials during ischemia were divided into two categories: border zone potentials (resting membrane potential [RMP] 73 +/- 3 mVe, action potential amplitude [APA] 81 ...
The clinical significance of bundle branch block complicating acute myocardial infarction. 2. Indications for temporary and permanent pacemaker insertion.
Authors: M CHindman, G SWagner, MJaRo, J MAtkins, M MScheinman, R WDeSanctis, A HHutter, LYeatman, MRubenfire, CPujura, MRubin, J JMorris
Journal: Circulation (1978)

The indication for prophylactic temporary and permanent pacing during acute myocardial infarction (MI) complicated by bundle branch block is high risk of progression via a Type II pattern to second or third degree (high degree) AV block during hospitalization or follow-up. In this study, determinants of high degree AV block during hospitalization and sudden death or recurrent high degree block during the first year of follow-up were examined in 432 patients with MI and bundle branch block. Timing of onset of bundle branch block, the involved fascicles, and the PR interval were examined as determinants of risk of progression to high degree AV block during MI. At highest risk were 186 patients with blocks involving the right bundle and at least one fascicle of the left bundle which were not documented on prior electrocardiograms. Risk was similar with (38%) or without (31%) accompanying first degree AV block. Patients with transient high degree AV block during MI had a 28% incidence of sudden death or recur...
HIV Prevention Among Black Women in the US—Time for Multimodal Integrated Strategies
Authors: Bisola O. Ojikutu, Kenneth Mayer
Journal: JAMA Network Open (2021)

Louisa Gilbert, PhD; Dawn Goddard-Eckrich, EdD; Mingway Chang, PhD; Timothy Hunt, PhD; Elwin Wu, PhD; Karen Johnson, PhD; Stanley Richards; Sharun Goodwin, BS; Richard Tibbetts, MS; Lisa R. Metsch, PhD; Nabila El-Bassel, PhD
Evidence for early dispersal of domestic sheep into Central Asia
Authors: William T. T. Taylor, Mélanie Pruvost, Cosimo Posth, William Rendu, Maciej T. Krajcarz, Aida Abdykanova, Greta Brancaleoni, Robert Spengler, Taylor Hermes, Stéphanie Schiavinato, Gregory Hodgins, Raphaela Stahl, Jina Min, Saltanat Alisher kyzy, Stanisław Fedorowicz, Ludovic Orlando, Katerina Douka, Andrey Krivoshapkin, Choongwon Jeong, Christina Warinner, Svetlana Shnaider
Journal: Nature Human Behaviour (2021)
Prospective evaluation of a sequential pacing and high-energy bidirectional shock algorithm for transvenous cardioversion in patients with ventricular tachycardia.
Authors: B DLindsay, SSaksena, S TRothbart, NWasty, DPantopoulos
Journal: Circulation (1987)

Rapid ventricular pacing alone or in combination with low- or intermediate-energy shocks has limited efficacy in cardioverting rapid ventricular tachycardia (VT) when delivered through two transvenous catheter electrodes. This prospective study determined the efficacy and safety of an algorithm that used a sequence of rapid ventricular pacing (RVP) and intermediate-energy (5 and 15 J) and high-energy (25J) single, bidirectional shocks delivered by two transvenous catheter electrodes in conjunction with a cutaneous electrode in patients with sustained VT. The bidirectional shock was simultaneously delivered over two electrical vectors via a common right ventricular apical cathode and tow anodes consisting of the superior vena caval catheter electrode and cutaneous patch. The electrical therapy delivered was determined by the cycle length of VT. Slow VT (cycle length greater than 300 msec) was sequentially treated by RVP followed by incremental bidirectional shocks of 5, 15, and 25 J. Rapid VT (cycle length...
Ensuring That LGBTQI+ People Count — Collecting Data on Sexual Orientation, Gender Identity, and Intersex Status
Authors: Kellan E. Baker, Carl G. Streed, Laura E. Durso
Journal: New England Journal of Medicine (2021)

For every gap in health and well-being whose contours we have mapped, the widespread lack of comprehensive data collection means that many more disparities — and the policy and programmatic interventions that might address them — remain unknown.
Systemic Lupus Erythematosus
Authors: L. C. Hill
Journal: BMJ (1957)

Lupus is a serious, potentially life-threatening disease. Its natural history is to culminate in a crescendo of autoimmunity and organ involvement. Difficulty arriving at the diagnosis may delay institution of therapy, which although helpful brings new problems. The fundamental understanding of this disease has made major strides. There is no consensus on the likely etiological agent(s), though evidence implicates Epstein-Barr virus, and the genetic approach to understanding etiology is in its infancy. Nevertheless, efficacious treatments are anticipated in the plethora of new biologics likely to have therapeutic effects in lupus, essentially a disease of immune dysregulation.
The natural history of trifascicular disease following permanent pacemaker implantation. Significance of continuing changes in atrioventricular conduction.
Authors: ELichstein, CRibas-Meneclier, DNaik, K DChadda, P KGupta, HSmith
Journal: Circulation (1976)

Seventy-two patients with trifasicular disease were followed for an average of 40 months following permanent pacemaker insertion. The indications for pacemaker insertion were either electrocardiographic evidence of complete heart block with a wide QRS escape complex or a pattern of bifasicular block with either periods of Mobitz type II atrioventricular (A-V) block or a documented history of syncope. The patients were then divided into three groups depending on subsequent change in A-V conduction. There were 31 (43%) patients with no change in A-V conduction, 17 (24%) with increasing A-V block, and 24 (33%) with decreasing A-V block. The characteristics of these three groups, including age and sex distribution, were compared and found to be similar. The incidence of previous transmural myocardial infarction as determined by electrocardiographic criteria was higher in the group with decreasing block. Survival curves showed a significantly decreased probablity of surviving for those with decreasing block co...
生物分解ゼラチンヒドロゲルを用いた塩基性線維芽細胞成長因子の持続遊離による重大な肢虚血患者に対する治療血管新生の新しい方法 第I-IIa試験の最初の報告
Authors: Marui Akira, Tabata Yasuhiko, Kojima Shinsuke, Yamamoto Masaya, Tambara Keiichi, Nishina Takeshi, Saji Yoshiaki, Inui Ken-ichi, Hashida Tohru, Yokoyama Sumiko, Onodera Rie, Ikeda Tadashi, Fukushima Masanori, Komeda Masashi
Journal: Circulation (2007)
Characteristics of sinoatrial conduction in patients with coronary artery disease.
Authors: JJordan, IYamaguchi, W JMandel
Journal: Circulation (1977)

Electrophysiologic studies were performed in 32 patients with angiographically documented coronary artery disease (CAD). Group I was composed of ten patients (31%) with severe stenosis (greater than or equal to 75%) proximal to the origin of the sinus node artery (SNA); group II was composed of five patients (16%) with moderate (50--75%) proximal stenosis; and group III was composed of 17 patients (53%) with insignificant (0--50%) proximal stenosis. The mean sinoatrial conduction time (SACT) for group I was 119 +/- 18 msec; group II was 84+/- 16 msec; and group III was 72 +/- 5 msec. The SACT was significantly longer in group I than in group III (P less than 0.005). In conclusion 1) in patients with CAD, SACT greater than 72 +/- 5 msec is abnormal; 2) the results suggest a pathogenetic role of CAD in the development of sinus node dysfunction; 3) the SACT is a more sensitive indicator of subtle sinus node dysfunction in CAD patients than is heart rate, sinus node response to artrial extrastimuli, or sinus ...
Effect of coronary hyperemia on Emax and oxygen consumption in blood-perfused rabbit hearts. Energetic consequences of Gregg's phenomenon.
Authors: YGoto, B KSlinker, M MLeWinter
Journal: Circulation Research (1991)

To assess the relation between increases in contractile function and oxygen consumption (VO2) during increased coronary flow (Gregg's phenomenon), we measured the end-systolic pressure-volume relation and the relation between VO2 and left ventricular systolic pressure-volume area (PVA, a measure of total mechanical energy output) in blood-perfused, isovolumically contracting rabbit hearts during control and intracoronary adenosine infusion. During adenosine infusion at a constant perfusion pressure (93 +/- 11 mm Hg), coronary flow increased by 99 +/- 76% (p less than 0.01), and the slope of the end-systolic pressure-volume relation, Emax (ventricular contractility index), increased by 18 +/- 15% (p less than 0.01). When compared at the same left ventricular volume, PVA increased by 20 +/- 14% (p less than 0.01) and VO2 by 19 +/- 15% (p less than 0.01) with adenosine. The VO2-PVA relation was linear under each condition (both median r = 0.98). With increased coronary flow, the VO2-intercept of the VO2-PVA ...
Regression of coronary artery dimensions after successful aortic valve replacement.
Authors: BVillari, O MHess, CMeier, APucillo, AGaglione, MTurina, H PKrayenbuehl
Journal: Circulation (1992)

BACKGROUNDThe effect of regression of myocardial hypertrophy on coronary artery dimensions was evaluated in patients with aortic valve disease who underwent valve replacement.METHODS AND RESULTSCross-sectional area (CSA) of the three major coronary arteries (left anterior descending [LAD], left circumflex [LCx], and right coronary artery) was determined by quantitative coronary arteriography in 15 patients with aortic valve disease before and 38 months (range, 14-113 months) after successful aortic valve replacement. Twelve normal subjects served as controls. Left ventricular (LV) angiographic mass was calculated according to the method of Rackley. CSA of the left coronary artery was larger in aortic valve disease than in controls (LAD, 15 versus 8 mm2, p less than 0.001; LCx, 14 versus 6 mm2, p less than 0.001). After valve replacement, CSA of the left coronary artery decreased (LAD, 12 mm2, p less than 0.05 versus before surgery; LCx, 11 mm2, p less than 0.05 versus before surgery) but remained signific...
Control of arteriolar resistance in heart failure. Partial attenuation of specific phosphodiesterase inhibitor-mediated vasodilation by digitalis glycosides.
Authors: GJondeau, MKlapholz, S DKatz, MMaher, MGalvao, PLevato, T HLeJemtel
Journal: Circulation (1992)

BACKGROUNDThe vasodilatory response to local specific type III phosphodiesterase inhibition with amrinone was evaluated before and immediately after local administration of digoxin in 14 patients with severe congestive heart failure (CHF).METHODS AND RESULTSA 3F polyethylene catheter was inserted into the common femoral artery for drug administration and pressure monitoring. Mean blood flow velocity (MBFV) was continuously determined in the superficial femoral artery by transcutaneous Doppler ultrasonography. After intra-arterial administration of 10 mg amrinone, group MBFV increased from 7.7 +/- 1.4 to 16.0 +/- 2.1 cm/sec (p less than 0.05, n = 10). Local administration of 20 micrograms digoxin, which was infused over 20 minutes, did not alter group MBFV (i.e., 8.2 +/- 1.6 versus 7.6 +/- 1.5 cm/sec; p = NS, n = 10). The second administration of 10 mg amrinone, which immediately followed completion of local digoxin infusion, increased group MBFV but to a lesser extent than that produced by the first amrin...
Digoxin-Induced Bidirectional Ventricular Tachycardia in a Patient With Hypokalemia
Authors: Kristopher S. Pfirman, Travis R. Huffman, Aniruddha Singh
Journal: JAMA Internal Medicine (2021)

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 Internal Medicine 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 Internal Medicine journal
Performance Of Eus-Guided Fna Of Solid Pancreatic Lesions According To The Level Of Operator-Experience
Authors: M Razpotnik, S Bota, G Essler, C Urak, J Weber-Eibel, M Peck-Radosavljevic
Journal: Endoscopy (2021)

Aims The amount of training before the independent performance of EUS-FNA of solid pancreatic lesions has been poorly described. In previous studies, rapid on-site cytopathological examination (ROSE) to evaluate the FNA sample adequacy was used. We aimed to evaluate the number of interventions needed to reach acceptable competence in EUS-guided FNA of solid pancreatic lesions in centers without ROSE.
The past, present, and future of breast cancer models for nanomedicine development
Authors: Paz Boix-Montesinos, Paula M. Soriano-Teruel, Ana Armiñán, Mar Orzáez, María J. Vicent
Journal: Advanced Drug Delivery Reviews (2021)

Even given recent advances in nanomedicine development of breast cancer treatment in recent years and promising results in pre-clinical models, cancer nanomedicines often fail at the clinical trial stage. Limitations of conventional in vitro models include the lack of representation of the stromal population, the absence of a three-dimensional (3D) structure, and a poor representation of inter-tumor and intra-tumor heterogeneity. Herein, we review those cell culture strategies that aim to overcome these limitations, including cell co-cultures, advanced 3D cell cultures, patient-derived cells, bioprinting, and microfluidics systems. The in vivo evaluation of nanomedicines must consider critical parameters that include the enhanced permeability and retention effect, the host's immune status, and the site of tumor implantation. Here, we critically discuss the advantages and limitations of current in vivo models and report how the improved selection and application of breast cancer models can improve the clinical translation of nanomedicines.
Factors affecting real-time, cross-sectional echocardiographic imaging of perimembranous ventricular septal defects.
Authors: J MCanale, D JSahn, H DAllen, S JGoldberg, L MValdes-Cruz, T WOvitt
Journal: Circulation (1981)

Recent studies suggest good prospective accuracy for two-dimensional echocardiographic imaging of ventricular septal defects (VSD). We obtained two-dimensional images with high-frequency, high-resolution scanners from 36 patients proved by cardiac catheterization to have perimembranous VSD. In 20 patients, the VSD was an isolated lesion and in 16 it was associated with other forms of heart disease. VSDs were imaged in long-axis, apical four-chamber and subcostal echocardiographic views. The smallest VSD imaged was 2 mm in diameter on echo; the largest, 23 mm. The imaged size of VSDs was larger at end-diastole than at end-systole by paired t test on all views (all p less than 0.005). VSD size also varied between views, with no predictive relationship except between apical and subcostal four-chamber views in diastole (r = 0.71, p less than 0.005). This agreed with qualitative direct observations of an ellipsoid or irregularly shaped VSD in operated patients. Echocardiographically measured VSD size normalize...
Reentrant ventricular arrhythmias in the late myocardial infarction period. Interruption of reentrant circuits by cryothermal techniques.
Authors: NEl-Sherif, RMehra, W BGough, R HZeiler
Journal: Circulation (1983)

Both sustained and nonsustained ventricular tachycardias were reproducibly induced in dogs 3 to 5 days after ligation of the left anterior descending coronary artery. Isochronal maps of ventricular activation were constructed from close bipolar electrograms recorded from the entire epicardial surface and selected intramural sites by a computerized multiplexing technique. The electrophysiologic data were correlated with the anatomic characteristics of the infarction. The induced tachycardias were due to reentrant activation in the surviving epicardial layer overlying the infarction. Cooling or cryoablation was applied to localized epicardial sites along the reentrant circuit to reversibly or permanently interrupt reentrant activation. The reentrant circuit could be consistently interrupted when cooling or cryoablation was applied to the distal part of the common reentrant wave front proximal to the site of earliest reactivation. Localized cooling of the site of earliest reactivation usually failed to inter...
Alpha 2-receptor-mediated vasoconstriction in patients with congestive heart failure.
Authors: S HKubo, T SRector, S MHeifetz, J NCohn
Journal: Circulation (1989)

alpha 2-Adrenoceptors exist postsynaptically to subserve vasoconstriction and presynaptically to modulate norepinephrine release into the synaptic cleft. Because adrenoceptors may down-regulate in response to chronic stimulation, we investigated the activity of alpha 2-receptor-mediated vasoconstriction in patients with congestive heart failure, who had increased levels of plasma norepinephrine. We used the isolated forearm model and intra-arterial infusions of subsystemic doses of yohimbine, a specific alpha 2-blocker, in 11 patients with heart failure and in 15 normal subjects. Yohimbine produced a dose-related increase in forearm blood flow and decrease in forearm vascular resistance. These findings were consistent with a direct vasodilator effect mediated by blockade of the postsynaptic alpha 2-vascular receptor. Furthermore, the vasodilator responses in patients with heart failure were similar to the normal subjects in terms of the percent increase in forearm blood flow, the dose-response relation, a...