tbuckley/cabot-search huggingface dataset:
Inhibition of accelerated coronary atherosclerosis with dehydroepiandrosterone in the heterotopic rabbit model of cardiac transplantation.
Authors: D MEich, J ENestler, D EJohnson, G HDworkin, DKo, A SWechsler, M LHess
Journal: Circulation (1993)

BACKGROUNDAccelerated coronary atherosclerosis has become a critical problem in cardiac transplantation. Although the pathogenesis of this disease is unknown, hypercholesterolemia has been shown to be a major risk factor.METHODS AND RESULTSTo study this problem, a hypercholesterolemic rabbit model of heterotopic cardiac transplantation was developed to study accelerated graft atherosclerosis. Based on suggestions in the literature, it was hypothesized that dehydroepiandrosterone (DHEA) may retard the progression of the disease. Using semiquantitative light microscopy, a predilection for the development of small vessel occlusive disease in the transplanted hearts was found. Chronic DHEA administration produced a 45% reduction in the number of significantly stenosed vessels in the transplanted hearts (p < 0.05) compared with controls and a 62% reduction in the nontransplanted hearts (p < 0.05), yielding an overall 50% reduction in the number of significantly stenosed vessels in both the transplanted and non...
Echocardiographic and hemodynamic relationships of ejection sounds.
Authors: P GMills, BBrodie, LMcLaurin, SSchall, ECraige
Journal: Circulation (1977)

The physiologic correlates of ejection sounds have been studied by simultaneous phonocardiograms, echocardiograms and high fidelity pressure tracings. Ejection sounds associated with semilunar valve stenosis or hypertension of the systemic or pulmonary circulation occur at the moment of complete opening of the aortic or pulmonary valve recorded echocardiographically. The start of opening of these valves occurs at the onset of the pressure rise in the corresponding great vessel and completion of valve opening always occurs on the pressure upstroke. The ejection sound in the presence of stenotic valves occurs with checking of the opening motion of the thickened valve cusps. Although the hypertensive ejection sounds also occur at the precise moment of full opening of the valve it remains to be seen whether this relationship is causal or coincidental.
Automatic and triggered impulse initiation in canine subepicardial ventricular muscle cells from border zones of 24-hour transmural infarcts. New mechanisms for malignant cardiac arrhythmias?
Authors: K HDangman, K PDresdner, SZaim
Journal: Circulation (1988)

With standard microelectrode techniques, electrical activity of cells in the epicardial border zones of infarcts in the canine heart were studied. Either automaticity or triggered activity (or both) occurred in each of the 12 preparations studied from 24-hour infarcts. One 24-hour preparation had continuous activity indistinguishable from low-potential (abnormal) automaticity. This automaticity was not effected by flecainide 1-5 mg/l. Two other 24-hour subepicardial muscle preparations also were automatic. However, nine preparations from the subepicardium were not automatic during superfusion with standard Tyrode's solution. Delayed afterdepolarizations (DADs) and triggered activity could be induced in all of these preparations by treatment with catecholamines. The amplitude of these DADs was directly related to the stimulus rate of the train of impulses used to elicit them, and their coupling interval was inversely related to this rate of stimulation. Triggered activity occurred from maximal diastolic po...
A multicenter randomized controlled trial indicates that paclitaxel-coated balloons provide no benefit for arteriovenous fistulas
Authors: Narayan Karunanithy, Emily J. Robinson, Farhan Ahmad, James O. Burton, Francis Calder, Simon Coles, Neelanjan Das, Anthony Dorling, Colin Forman, Ounali Jaffer, Sarah Lawman, Raghuram Lakshminarayan, Rhys Lewlellyn, Janet L. Peacock, Raymond Ramnarine, Irene Rebollo Mesa, Shoaib Shaikh, James Simpson, Kate Steiner, Rebecca Suckling, Laszlo Szabo, Douglas Turner, Ashar Wadoodi, Yanzhong Wang, Graeme Weir, C. Jason Wilkins, Leanne M. Gardner, Michael G. Robson
Journal: Kidney International (2021)

The role of paclitaxel-coated balloons has been established in the coronary and peripheral arterial circulations with recent interest in the use of paclitaxel-coated balloons to improve patency rates following angioplasty of arteriovenous fistulas. To assess the efficacy of paclitaxel-coated angioplasty balloons to prolong the survival time of target lesion primary patency in arteriovenous fistulas, we designed an investigator-led multi-center randomized controlled trial with follow up time variable for a minimum of one year. Patients with an arteriovenous fistula who were undergoing an angioplasty for a clinical indication were included but patients with one or more lesions outside the treatment segment were excluded. Following successful treatment with a high-pressure balloon, 212 patients were randomized. In the intervention arm, the second component was insertion of a paclitaxel-coated balloon. In the control arm, an identical procedure was followed, but using a standard balloon. The primary endpoint was time to loss of clinically driven target lesion primary patency. Primary analysis showed no significant evidence for a difference in time to end of target lesion primary patency between groups: hazard ratio 1.18 with a 95% confidence interval of 0.78 to 1.79. There were no significant differences for any secondary outcomes, including patency outcomes and adverse events. Thus, our study demonstrated no evidence that paclitaxel-coated balloons provide benefit, following standard care high-pressure balloon angioplasty, in the treatment of arteriovenous fistulas. Hence, in view of the benefit suggested by other trials, the role of paclitaxel-coated angioplasty balloons remains uncertain.
Hemodynamic and neurohormonal effects of clonidine in patients with preganglionic and postganglionic sympathetic lesions. Evidence for a central sympatholytic action.
Authors: J SKooner, RBirch, H LFrankel, W SPeart, C JMathias
Journal: Circulation (1991)

BACKGROUNDClonidine, a partial presynaptic and postsynaptic alpha-adrenoceptor agonist, has been shown to lower blood pressure in normal subjects but not in tetraplegics; however, the mechanisms of this action have not been elucidated.METHODS AND RESULTSThe hemodynamic and hormonal basis of the hypotensive action of clonidine was investigated in tetraplegics with complete cervical spinal cord transection and preganglionic sympathetic denervation, in patients with unilateral brachial plexus injury and postganglionic sympathetic denervation, and in normal subjects. In normal subjects, the fall in blood pressure after clonidine infusion was accompanied by a reduction in cardiac output that was predominantly due to a fall in stroke volume and in heart rate. The lack of fall in blood pressure, cardiac output, and stroke volume in tetraplegics indicates that these effects are exerted at a supraspinal level and require intact descending sympathetic pathways. After clonidine infusion, digital skin vasodilatation ...
Evidence that bradykinin stimulates renal prostaglandin synthesis by a mechanism distinct from that of other vasoactive substances.
Authors: C LCooper, K UMalik
Journal: Circulation Research (1987)

Arginine-vasopressin (AVP), angiotensin II (AII), and norepinephrine (NE) are known to stimulate prostaglandin (PG) synthesis in the intact rat kidney perfused with Tyrode's solution by a mechanism that requires intracellular Ca2+, while PG synthesis elicited by bradykinin (BK) is independent of Ca2+. To elucidate further the differences in the mechanism of action of BK and other vasoactive agents, in this preparation we have investigated the effect of caffeine, an agent known to interfere with the uptake and storage of Ca2+ in intracellular sites, on renal output of PGE2 and 6-keto-PGF1 alpha elicited by AVP, AII, NE, and BK; various combinations of the maximal doses of BK, AII, AVP, and NE on renal PG synthesis; and RHC 80267, an inhibitor of diglyceride and monoglyceride lipase, on the output of PGs produced by these vasoactive agents. Infusion of 1 mM caffeine inhibited PG output elicited by AVP, AII, and NE but not that caused by BK in the absence of extracellular Ca2+. Combined administration of max...
The pathologic correlates of the electrocardiogram: complete left bundle branch block.
Authors: C JHavelda, G SSohi, N CFlowers, L GHoran
Journal: Circulation (1982)

To assess whether gross pathologic differences exist between hearts with left bundle branch block (LBBB) and left-axis deviation (LAXD) and those with LBBB and a normal frontal plane axis, we examined 70 hearts with LBBB in a series of 1410 sequential dissections (5%). Thirty-two hearts had LAXD and 34 had normal axes on the correlative ECG. Left ventricular enlargement occurred frequently (93%). No significant differences were found in age distribution, left ventricular weight, coronary anatomy or infarct location. Quantitative analysis revealed larger inferoposterolateral and apical infarcts in hearts with LBBB and LAXD (p less than 0.01). The accuracy of various electrocardiographic signs of left ventricular enlargement and myocardial infarction in the presence of LBBB was assessed. Voltage criteria and QRS duration poorly define anatomic chamber enlargement. Anterior infarction is suggested by a q or pathological Q wave in lead I, a q wave in leads I, V5 and V6, or notched S waves in V3 or V4. Patholo...
Age-related decrease of calcitonin gene-related peptide-containing vasodilator innervation in the mesenteric resistance vessel of the spontaneously hypertensive rat.
Authors: HKawasaki, ASaito, KTakasaki
Journal: Circulation Research (1990)

We previously demonstrated that the mesenteric resistance blood vessels have nonadrenergic, noncholinergic vasodilator innervation in which calcitonin gene-related peptide (CGRP) is a possible neurotransmitter. The role of CGRP-containing vasodilator nerves in hypertension was investigated in perfused mesenteric vascular beds isolated from spontaneously hypertensive rats (SHR). The adrenergic vasoconstrictor responses to perivascular nerve stimulation in both SHR (8-, 15-, and 30-week-old) and age-matched Wistar-Kyoto (WKY) rat preparations increased with aging, but the response was greater in SHR than in WKY rats at all ages. The preparation isolated from SHR and WKY rats was precontracted by continuous perfusion of Krebs' solution containing 7 x 10(-6) M methoxamine plus 5 x 10(-6) M guanethidine. In both SHR and WKY rats, perivascular nerve stimulation (1-8 Hz) produced frequency-dependent vasodilation, which was blocked by 1 x 10(-7) M tetrodotoxin, pretreatment with 5 x 10(-7) M capsaicin, and denerv...
Influence of aortic pressure on effective regurgitant orifice area in aortic regurgitation.
Authors: E SCaguioa, S CReimold, SVélez, R TLee
Journal: Circulation (1992)

BACKGROUNDThe regurgitant volume in aortic regurgitation is determined by the diastolic filling period, the pressure gradient between the left ventricle and aorta, and the hemodynamic size of the regurgitant orifice area.METHODS AND RESULTSTo test the hypothesis that the aortic regurgitant orifice area is related to aortic pressure and aortic root size, 16 fresh calf heart and aorta specimens were studied in vitro using a continuous-flow system over a range of aortic pressures. Regurgitant orifice areas were calculated as the ratio of flow divided by peak velocity through the valve measured by image-guided continuous-wave Doppler, and aortic root areas were measured by two-dimensional echocardiography. When the defect was created at the edge of the noncoronary leaflet (n = 10), regurgitant orifice area gradually increased 51 +/- 33% when aortic pressure was increased from approximately 40 to 152 cm of water (29.6 to 112.5 mm Hg) (p less than 0.0001). Similarly, the aortic root size increased 82 +/- 29% wh...
18F-PSMA-1007 Uptake in Pulmonary Lymphangitic Carcinomatosis Metastasis From Prostate Cancer
Authors: Bo-Le Liu, Jun-Jie Hong, Kun Tang, Jie Lin, Xiang-Wu Zheng
Journal: Clinical Nuclear Medicine (2021)

A 55-year-old man with cough, bone pain, and cervical lymphadenopathy underwent both 18F-FDG and 18F-PSMA-1007 PET/CT scans with clinical suspicion of malignant disease. Compared with 18F-FDG PET/CT, 18F-PSMA PET/CT showed intense tracer uptake in the prostate gland, lungs, osteogenic lesions, and multiple lymph nodes. Interestingly, we also found the high tracer concentration of pulmonary lymphangitic carcinomatosis, a very rare form of prostate cancer metastasis to the lung, on 18F-PSMA-1007 PET/CT images.
Screening for Hypertension
Authors: Louis A. De Nino
Journal: Annals of Internal Medicine (1990)

Letters and Corrections15 May 1990Screening for HypertensionLouis A. De Nino, PhD, Cynthia D. Mulrow, MD, MScLouis A. De Nino, PhDSearch for more papers by this author, Cynthia D. Mulrow, MD, MScSearch for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-112-10-796_3 SectionsAboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail ExcerptTo the Editor: We question whether Littenberg, Garber, and Sox (1) have really shown the cost-effectiveness of hypertension screening for all adults. They assumed that most patients can be treated using low-cost drugs, with annual treatment cost estimated at $300 (range, $50 to $500).Standard hypertension treatment includes three or four follow-up visits and two or three sets of laboratory work annually. A physician visit costs between $30 and $50, and laboratory work costs approximately $25 to $50. Drug costs alone can range from $36 per year for reserpine to $300 for propranolol hydrochloride to over $1400 for captopril (2)....References1. Littenberg B, Garber A, and Sox H. Screening for hypertension. Ann Intern Med. 1990;112:192-202. LinkGoogle Scholar2. Edelson J, Weinstein M, Tosteson A, Williams L, Lee T, and Goldman L. Long-term cost-effectiveness of various initial monotherapies for mild to moderate hypertension. JAMA. 1990;263:407-13. CrossrefMedlineGoogle Scholar3. Stason W. Opportunities for improving the cost-effectiveness of antihypertensive treatment. Am J Med. 1986;81(Suppl 6C):45-9. CrossrefMedlineGoogle Scholar4. Weinstein M and Stason W. Cost-effectiveness of interventions to prevent or treat coronary heart disease. Ann Rev Public Health. 1985;6:41-63. CrossrefMedlineGoogle Scholar This content is PDF only. To continue reading please click on the PDF icon. Author, Article, and Disclosure InformationAuthors: Louis A. De Nino, PhD; Cynthia D. Mulrow, MD, MScAffiliations: Audie L. Murphy Memorial VA Hospital University of Texas Health Science Center at San Antonio San Antonio, TX 78284 PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetails Metrics 15 May 1990Volume 112, Issue 10Page: 796-797KeywordsDrugsHypertensionResearch laboratoriesReserpine ePublished: 1 December 2008 Issue Published: 15 May 1990 PDF downloadLoading ...
Enhanced responsiveness to carotid baroreceptor unloading in conscious dogs during development of perinephritic hypertension.
Authors: D AKirby, S FVatner
Journal: Circulation Research (1987)

The effects of unloading the carotid sinus baroreceptors before and during the development of perinephritic hypertension were studied in conscious dogs instrumented with aortic catheters to measure arterial pressure and heart rate, and electromagnetic flow probes to measure cardiac output and calculate total peripheral resistance. Prior to hypertension, bilateral carotid occlusion (BCO) increased mean arterial pressure by 38 +/- 2 from 101 +/- 2 mm Hg and total peripheral resistance by 19 +/- 2 from 46 +/- 3 mm Hg/l/min, while cardiac output and heart rate did not change from 2,299 +/- 128 ml/min and 84 +/- 4 beats/min, respectively. At 2 weeks after renal wrapping, there were significant increases in baseline mean arterial pressure, cardiac output, and total peripheral resistance and decreases in heart rate; BCO increased mean arterial pressure by 59 +/- 5 from 130 +/- 4 mm Hg, heart rate by 36 +/- 5 beats/min from 69 +/- 3 beats/min, and cardiac output by 458 +/- 103 from 2,711 +/- 239 ml/min. By 4 week...
Noninvasive quantitation of regional myocardial oxygen consumption in vivo with [1-11C]acetate and dynamic positron emission tomography.
Authors: D BBuxton, C ANienaber, ALuxen, ORatib, HHansen, M EPhelps, H RSchelbert
Journal: Circulation (1989)

The usefulness of [1-11C]acetate as a tracer of overall myocardial oxidative metabolism for use with positron emission tomography has been investigated in 12 closed-chest dogs. Myocardial 11C activity clearance kinetics after intravenous administration of [1-11C]acetate in dogs have been determined noninvasively by positron emission tomography. Biexponential fitting of regional myocardial 11C time-activity curves was performed to give clearance half-times and fractional distribution. The rate constant k1 for the early rapid phase of 11C activity clearance was found to correlate linearly with myocardial oxygen consumption (y = 0.0156x + 0.039; SEE = 0.023; r = 0.95). k1 was approximately 7% lower in septal sectors compared with the left ventricular free wall, suggesting that regional oxygen consumption in the septum was lower; a concomitant regional attenuation of blood flow in the septum relative to the left ventricular free wall was also observed. In dogs using carbohydrates as the predominant fuel, k1 o...
Evaluation of biplane color Doppler transesophageal echocardiography in 200 consecutive patients.
Authors: ROmoto, SKyo, MMatsumura, P MShah, HAdachi, YYokote, YKondo
Journal: Circulation (1992)

BACKGROUNDWe developed the first biplane transesophageal echocardiography (TEE) probe with two orthogonal transducers, allowing synchronous side-by-side displays of the heart on a monitor TV, and compared its diagnostic value with that of conventional single-plane TEE using commercially available Doppler equipment in 200 consecutive patients intraoperatively, perioperatively, or on an outpatient basis.METHODS AND RESULTSInsertion was easy, except in one patient with a mediastinal tumor, and no complications were encountered. Both transverse and longitudinal scans allowed correct identification of true and false lumina in all 30 aortic dissection examinations, but longitudinal scanning was slightly superior in detecting types I and III entry sites. Three entries that were not detected by transverse scanning (two of DeBakey type I and one of type III) were visualized by longitudinal scanning. Among 37 cases of mitral regurgitation (MR), longitudinal scans were significantly superior (p less than 0.05) in re...
Assessment of severity of mitral regurgitation by measuring regurgitant jet width at its origin with transesophageal Doppler color flow imaging.
Authors: CTribouilloy, W FShen, J PQuéré, J LRey, DChoquet, HDufossé, J PLesbre
Journal: Circulation (1992)

BACKGROUNDThe ability of transesophageal color Doppler echocardiography to provide high-resolution images of both cardiac structure and blood flow in real time is advantageous for many clinical purposes. This study was performed to determine the utility of the regurgitant jet width at its origin measured by transesophageal Doppler color flow imaging in the assessment of severity of mitral regurgitation.METHODS AND RESULTSSixty-three consecutive patients with mitral regurgitation underwent transesophageal color Doppler examination, and the diameter of regurgitant jet at its origin was measured. Both right and left cardiac catheterizations were performed within 24 hours of Doppler studies, and angiographic grading of mitral regurgitation and regurgitant stroke volume were evaluated. There was a close relation between the jet diameter at its origin measured by transesophageal Doppler color flow imaging and the angiographic grade of mitral regurgitation (r = 0.86, p less than 0.001). A jet diameter of 5.5 mm ...
A quantitative analysis of use-dependent ventricular conduction slowing by procainamide in anesthetized dogs.
Authors: CVillemaire, PSavard, MTalajic, SNattel
Journal: Circulation (1992)

BACKGROUNDUse-dependent effects of antiarrhythmic drugs on phase 0 sodium current result in rate-dependent conduction slowing with important potential clinical consequences. The purpose of the present study was to determine whether state-dependent interactions of procainamide with sodium channels can be analyzed based on conduction changes in vivo.METHODS AND RESULTSProcainamide infusions were used to produce stable drug concentrations causing greater than or equal to 25% conduction slowing at a basic cycle length (BCL) of 300 msec in morphine/chloralose-anesthetized dogs with formalin-induced atrioventricular block. Computer-based epicardial activation mapping was applied to assess the time course and pattern of conduction over a wide range of BCLs before and after drug administration. Action potential duration was measured from recordings of monophasic action potentials. The onset and steady-state values of fractional sodium channel block estimated from conduction changes were fitted to equations obtain...
Antihypertensive Drugs
Authors: Irvine H. Page
Journal: New England Journal of Medicine (1981)

IT is widely assumed that most important drugs are discovered through academic research. Indeed, in the case of the antihypertensive drugs credit has been allotted both to the universities and to government, as shown by such encomiums as the Lasker awards. In fact, as I hope to show, all such drugs came from a few pharmaceutical companies, and most of the investigators' names are scarcely known.It is becoming customary to denigrate the history of science by ignoring the origins of discovery — a practice surely not in the best interests of truth and equity. For this reason I have . . .
Therapeutic targets in lung tissue remodelling and fibrosis
Authors: Gang Liu, Ashleigh M. Philp, Tamera Corte, Mark A. Travis, Heidi Schilter, Nicole G. Hansbro, Chris J. Burns, Mathew S. Eapen, Sukhwinder S. Sohal, Janette K. Burgess, Philip M. Hansbro
Journal: Pharmacology & Therapeutics (2021)
Validation of [1-11C]acetate as a tracer for noninvasive assessment of oxidative metabolism with positron emission tomography in normal, ischemic, postischemic, and hyperemic canine myocardium.
Authors: J JArmbrecht, D BBuxton, H RSchelbert
Journal: Circulation (1990)

Extraction and clearance kinetics of [1-11C]acetate were examined in 65 experiments in 30 open-chest dogs. Twenty-nine studies were performed at control, 13 during ischemia, eight after reperfusion, 13 during dipyridamole-induced hyperemia, and two during alteration of cardiac workload. [1-11C]Acetate was injected directly into the left anterior descending coronary artery, and myocardial tissue-time activity curves were recorded with a gamma probe. The single-pass extraction fraction averaged 64.2 +/- 9.7% in control, 65.3 +/- 9.1% in ischemia, 70.0 +/- 4.4% in reperfusion, and 46.5 +/- 7.4% in dipyridamole-induced hyperemia groups. 11C clearance was biexponential in all cases. The rate constant k1 for the first rapid clearance phase correlated closely with myocardial oxygen consumption (r = 0.94) in control, ischemia, reperfusion, and dipyridamole-induced hyperemia groups. Monoexponential fitting of only the first linear part of the clearance curve yielded the rate constant kmono, which also correlated w...