tbuckley/cabot-search huggingface dataset:
Beneficial effects of high-dose diltiazem in patients with persistent effort angina on beta-blockers and nitrates: a randomized, double-blind, placebo-controlled cross-over study.
Authors: W EBoden, E WBough, M JReichman, V BRich, P MYoung, K SKorr, R SShulman
Journal: Circulation (1985)

The effects of orally administered diltiazem combined with maximally tolerated doses of beta-blockers and nitrates were assessed in 12 patients, who during stress testing exhibited persistent effort angina and continued objective evidence for inducible myocardial ischemia. Patients performed multistage semisupine exercise on a bicycle ergometer during equilibrium-gated radionuclide angiography after consecutive 2 week treatment periods of placebo or diltiazem 90 mg qid (mean dose 340 mg/day) combined with maximally tolerated propranolol (mean dose 178 mg/day) and isosorbide dinitrate (mean dose 137 mg/day). All medications (including diltiazem or placebo) were administered four times daily for the duration of the study. Diltiazem or placebo was administered according to a double-blind design, with randomized cross-over at the end of each 2 week treatment period. The average number of angina attacks decreased during the double-blind cross-over phase of the trial (7 +/- 7 episodes/week at baseline vs 4 +/- ...
Static pressure-flow relation in the total systemic vascular bed of the dog and its modification by the baroreceptor reflex.
Authors: KSagawa, AEisner
Journal: Circulation Research (1975)

To evaluate arterial baroreceptor reflex control of total systemic vascular resistance, we studied the relation between mean arterial blood pressure (P) and mean aortic flow (Q) before and after the reflex was abrogated. In 12 dogs with a perfusion pump interposed at the vena-caval-right atrial junction, Q was kept at 60, 80, 100, 120, and 140 ml/min kg-1 for up to 20 minutes. There was little time-dependent change in P at any of these flows. When the reflex was intact, the mean P-Q curve was only slightly convex to the pressure axis; its linearized slope was 0.55 mm Hg-min-kg/ml and its pressure axis intercept was 44 mm Hg. After section of the sinovagal nerves, administration of hexamethonium (30 mg/kg, iv) and norepinephrine (3-5 mug/kg min-1, iv), or both, the slope became 0.96 mm Hg-min-kg/ml and the pressure axis intercept was about 3 mm Hg. Similar findings were obtained in 3 closed-chest dogs in which P was servocontrolled and Q was measured. Therefore, we think that the conventional practice of c...
Effects of an increase in intracellular free [Mg2+] after myocardial stunning on sarcoplasmic reticulum Ca2+ transport.
Authors: S MKrause, DRozanski
Journal: Circulation (1991)

BACKGROUNDMyocardial stunning has been associated with a greater than twofold increase in intracellular free [Mg2+] from 0.6 to 1.5 mM. The effect of this increase in free [Mg2+] on the function of the sarcoplasmic reticulum (SR) Ca2+ pump was assessed in SR isolated from Langendorff perfused, isovolumic rabbit hearts after 15 minutes of global ischemia.METHODS AND RESULTSOur results indicate that myocardial stunning results in a shift in the Ca2+ sensitivity of oxalate-supported, Ca2+ transport over the entire range of free [Ca2+] associated with the cardiac cycle. Using 0.6 mM free Mg2+ as control, maximal rates of Ca2+ transport occurred at 1 microM free Ca2+ (control, 519 +/- 32; stunned, 337 +/- 37 nmol Ca2+.min-1.mg-1). At 0.56 microM free Ca2+, SR Ca2+ transport was reduced from a control of 351 +/- 49 to 263 +/- 12 nmol Ca2+.min-1.mg-1 at 0.6 mM free [Mg2+]. Moreover, an increase in the free [Mg2+] from 0.6 to 1.5 mM results in a greater shift in the Ca2+ activation curve with no change in the lev...
Novel cardiac myofilament desensitizing factor released by endocardial and vascular endothelial cells.
Authors: A MShah, AMebazaa, R CWetzel, E GLakatta
Journal: Circulation (1994)

BACKGROUNDRecent studies suggest that both endocardial endothelium and coronary vascular endothelium influence myocardial contraction, but the mediators responsible and their mechanisms of action are not well defined.METHODS AND RESULTSWe investigated the effects of cultured endocardial endothelial and vascular endothelial cell superfusate on contraction and intracellular calcium transients of isolated rat cardiac myocytes. Endothelial cell superfusate induced a potent negative inotropic effect, with a rapid reversible decrease in myocyte twitch amplitude, earlier twitch relaxation, and a significant increase in diastolic length. This effect was not associated with significant changes in intracellular calcium or pH; was not attributable to nitric oxide, prostanoids, cGMP, or protein kinase C activation; and did not involve pertussis toxin-sensitive G proteins. The activity was stable at 37 degrees C for several hours, was not destroyed by protease treatment, and was found in low-molecular-weight (< 1 kD) ...
Factors in predicting blood pressure change.
Authors: DSparrow, A JGarvey, BRosner, H EThomas
Journal: Circulation (1982)

A total of 1166 male participants (ages 23--80 years) of the Normative Aging Study who had baseline blood pressure less than 140/90 mm Hg were followed prospectively for 10 years. Blood pressures were taken at 5- and 10-year follow-up examinations. Multiple linear regression analysis indicated that baseline levels of systolic pressure, hematocrit, subscapular skinfold thickness and age were significant predictors of systolic pressure change during the follow-up period. Baseline levels of diastolic pressure, hematocrit, and body mass index were significant predictors of diastolic pressure change. Multiple logistic regression analysis revealed that only baseline blood pressure and hematocrit were significant predictors of subsequent blood pressure elevation to more than 159 mm Hg systolic or 94 mm Hg diastolic. Although the mechanisms by which hematocrit and body build affect blood pressure are unknown, these results suggest that identifying hypertension-prone subjects and delaying or preventing hypertensio...
Flow into ischemic myocardium and across coronary collateral vessels is modulated by a waterfall mechanism.
Authors: CEng, E SKirk
Journal: Circulation Research (1984)

If a coronary artery is ligated and the distal end cannulated, blood flows retrograde from the cannula when vented to the atmosphere. By varying the height of the outflow tubing, and thereby changing the outflow pressure, pressure-flow relationships can be constructed. We used this technique in eight dogs to assess the characteristics of blood flow into ischemic myocardium. Above a back pressure of 10 mm Hg, increasing back pressure resulted in a decrease of retrograde blood flow. However, below a back pressure of about 10 mm Hg (10.7 +/- 2.7 mm Hg), alterations in back pressure did not result in changes in retrograde blood flow (back pressure-independent region). The transition at 10 mm Hg is interpreted as the critical waterfall pressure in ischemic myocardium. In another group of eight dogs, the ischemic bed was completely embolized with 25-micron sized microspheres to prevent RBF from entering the tissue as back pressure was raised. Pressure-flow relationships performed in this group revealed a back p...
Identification and characterization of developmentally regulated genes in vascular smooth muscle cells.
Authors: D KHan, GLiau
Journal: Circulation Research (1992)

We wish to understand the process of smooth muscle cell (SMC) proliferation and maturation during late fetal development and have examined some of the molecular changes associated with blood vessel maturation in late gestational and early neonatal life. By differential screening of a fetal aortic smooth muscle cDNA library, we identified a gene (F-31) that was developmentally regulated in aortic smooth muscle. The F-31 gene encodes a 2.3-kb RNA that was highly expressed in fetal aortic smooth muscle (25-day gestation), was lower in newborns, and was undetectable in the aortic smooth muscle of 4-week-old animals. F-31 was also highly expressed in fetal muscle, esophagus, heart, liver, lung, and placenta; its expression was lower in skin, kidney, and brain. By contrast, the expression of F-31 was low or undetectable in the corresponding tissue of adult animals. DNA sequence analysis of cDNAs encoding F-31 and data base comparison revealed a 73% homology with a previously identified, developmentally regulate...
Enkephalinase inhibition increases plasma atrial natriuretic peptide levels, glomerular filtration rate, and urinary sodium excretion in rats with reduced renal mass.
Authors: H MLafferty, MGunning, PSilva, M BZimmerman, B MBrenner, SAnderson
Journal: Circulation Research (1989)

To investigate the in vivo effects of inhibition of endopeptidase 24.11, an enkephalinase enzyme shown to be involved in atrial natriuretic peptide (ANP) breakdown in vitro, we infused phosphoramidon, a specific inhibitor of endopeptidase 24.11, into rats with reduced renal mass (and chronic extracellular volume expansion) and into normal rats. Relative to baseline values in rats with remnant kidneys, phosphoramidon led to elevations of plasma ANP levels and concomitant increases in urinary sodium excretion, fractional excretion of sodium, glomerular filtration rate, filtration fraction, and urinary cyclic GMP excretion. Similar changes in renal function and urinary cyclic GMP excretion were obtained with thiorphan, another endopeptidase 24.11 inhibitor. These enhanced ANP levels and renal actions were not observed with phosphoramidon in normal rats. These results show that plasma ANP levels can be modulated in rats with reduced renal mass by inhibition of endopeptidase 24.11.
Risk and Incidence of Pulmonary Diseases among HIV-infected Patients in the Era of Combination Antiretroviral Therapy
Authors: Kristina Crothers, Laurence Huang, Adeel A. Butt
Journal: American Journal of Respiratory and Critical Care Medicine (2011)

Cohort Study Virtual Cohort.The findings of this study further emphasize the role of bacterial pneumonia along with chronic obstructive pulmonary disease as important causes of morbidity among HIV-infected patients.While the message that behavioral interventions to enhance adherence to smoking cessation (2, 3) and combination ART (4) are important, surprisingly, the authors did not analyze the impact of pneumococcal vaccination on the incidence of bacterial pneumonia.Among the HIVinfected veterans of the same cohort, a previous study by Rodriguez-Barradas and colleagues (3) has shown that, although less than 50% of the veterans received pneumococcal polysaccharide vaccination, pneumococcal vaccination offered protection against pneumonia in this cohort.Furthermore, a recent double-blind, randomized, placebo-controlled clinical trial (5) has demonstrated that the 7-valent pneumococcal conjugate vaccine protected HIV-infected adults from recurrent pneumococcal infection caused by vaccine serotypes or serotype 6A.Although the cost-effectiveness of pneumococcal conjugate vaccine versus polysaccharide vaccine remains debatable in these aging populations (6), further analyses using the data from this large cohort will be worthwhile and informative.
A Modeling Approach to Radiation Therapy in the Era of COVID-19
Authors: Jimmy T. Efird, Tarun Podder, Tithi Biswas
Journal: JAMA Network Open (2021)

Shervin Tabrizi, MD; Lorenzo Trippa, PhD; Daniel Cagney, MD; Ayal A. Aizer, MD; Shyam Tanguturi, MD; Steffen Ventz, PhD; Geoffrey Fell, MSc; Jennifer R. Bellon, MD; Harvey Mamon, MD, PhD; Paul L. Nguyen, MD; Anthony V. D'Amico, MD, PhD; Daphne Haas-Kogan, MD; Brian M. Alexander, MD, MPH; Rifaquat Rahman, MD
Diffusion permeability of an isolated rete mirabile.
Authors: E ARasio, MBendayan, C AGoresky
Journal: Circulation Research (1977)

The rete mirabile of the swimbladder of the eeel is a countercurrent exchange organ composed of alternately disposed and venous capillaries. A countercurrent perfusion of these was set up by isolating arterial input and outflow, and venous input and outflow, and perfusing each set of capillaries with oxygenated albumin-containing Krebs-Ringer bicarbonate buffer. Constant arterial infusions containing tracer albumin, inulin, 3-O-methylglucose, urea, and water were begun and tracer concentrations at the outlets of arterial and venous beds were determined. Capillary permeabilities were determined from the resulting steady state values. The method of calculation of permeability values from the data acquired in the rete involves no approximations and appears to yield unequivocal values. For the solutes, the values appear compatible with transcapillary passage by free diffusion. No evidence of increasing restriction (in comparison to the diffuse coefficients) was found over the range of molecular sizes explored...
Postischemic free radical production in the venous blood of the regionally ischemic swine heart. Effect of deferoxamine.
Authors: G WMergner, W BWeglicki, J HKramer
Journal: Circulation (1991)

BACKGROUNDWe tested the hypothesis that secondarily produced free radicals can be detected in venous coronary effluent without the need for direct exposure of postischemic tissue to the spin trapping agent alpha-phenyl-tert-butylnitrone (PBN).METHODS AND RESULTSThe left anterior descending coronary artery (LAD) of pigs was ligated for 15, 30, 40, or 60 minutes, and the tissue was subsequently reperfused for 60 minutes. Venous effluent (6.5 ml) from the risk area was withdrawn sequentially at 1.5-minute intervals during reperfusion. The effluent blood was immediately infused (4.5 ml/min) with an isotonic saline solution containing 120 mM PBN: Preischemic control effluent samples were collected in an identical fashion. Plasma from each sample was extracted in organic solvent and subsequently analyzed by electron spin resonance (ESR) spectroscopy. Another group of pigs received an infusion of the metal chelator deferoxamine mesylate (25 mg/kg/hr) into the right atrium starting 1 hour before the 40-minute lig...
Phase 2 Trials with Mgta-456, Single Cord Blood Units (CBU) Expanded with an Aryl Hydrocarbon Receptor (AHR) Antagonist, Demonstrate Uniform Engraftment and Rapid Hematopoietic Recovery in Patients Following Myeloablative or Non-Myeloablative Conditioning
Authors: John E. Wagner, Claudio G Brunstein, Todd E. DeFor, Anthony E. Boitano, David McKenna, Darin Sumstad, Bastiano Sanna, Conrad Bleul, Michael P Cooke
Journal: Blood (2017)
Screening for Hepatitis C Virus Infection in Adults
Authors: Ned Calonge, Janet D. Allan
Journal: Annals of Internal Medicine (2004)

Letters5 October 2004Screening for Hepatitis C Virus Infection in AdultsNed Calonge, MD, MPH and Janet D. Allan, PhD, RN, CSNed Calonge, MD, MPHFrom U.S. Preventive Services Task Force, Rockville, MD 20852.Search for more papers by this author and Janet D. Allan, PhD, RN, CSFrom U.S. Preventive Services Task Force, Rockville, MD 20852.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-141-7-200410050-00022 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail IN RESPONSE:We appreciate the opportunity to comment on this thoughtful letter regarding the U.S. Preventive Services Task Force's grade I recommendation for screening high-risk individuals for HCV infection. It is important to begin with a correction: A grade I recommendation is not a recommendation against screening, as Drs. Rich, Taylor, and Allen suggest. The Task Force recommends against a service only when it finds at least fair evidence that the service is ineffective or that the harms of providing the service outweigh the benefits (such services are then given a grade D recommendation). Rather, when assigning a grade I ...Reference1. Harris RP, Helfand M, Woolf SH, Lohr KN, Mulrow CD, Teutsch SM, et al . Current methods of the US Preventive Services Task Force: a review of the process. Am J Prev Med. 2001;20:21-35. [PMID: 11306229] CrossrefMedlineGoogle Scholar Author, Article, and Disclosure InformationAffiliations: From U.S. Preventive Services Task Force, Rockville, MD 20852. PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetailsSee AlsoScreening for Hepatitis C Virus Infection: A Review of the Evidence for the U.S. Preventive Services Task Force Roger Chou , Elizabeth C. Clark , and Mark Helfand Screening for Hepatitis C Virus Infection in Adults Josiah D. Rich , Lynn E. Taylor , and Scott A. Allen Metrics 5 October 2004Volume 141, Issue 7Page: 576KeywordsBehaviorHepatitis C virusInfectious hepatitisPrevention, policy, and public healthViral loadViral transmission and infection ePublished: 5 October 2004 Issue Published: 5 October 2004 CopyrightCopyright © 2004 by American College of Physicians. All Rights Reserved.PDF DownloadLoading ...
Inhibition of Lactation
Authors: D. MacDonald, K. O'Driscoll
Journal: BMJ (1969)

While controversy continues about the most effective oestrogen for suppression of lactation (18 January p. 184) their is increasing concern over the relationship between oestrogen and puerperal thromboembolism.  A mother who elects to bottle-feed does not want lactation inhibited; she wishes to be free from breast discomfort.  Breast engorgement is self-limiting in the absence of the sucking reflex.  The success of any oestrogen in preventing engorgement must be measured against the results using a placebo.  Since such a trial was carried out in this hospital 25000 consecutive patients have recieved no specific treatment to inhibit lactation.  Analgesics are available for patients who require them.  There has been no death from thromboembolism in this hospital over the same period of time.(Full text)
Glucocorticoids induce the production of the chemoattractant CCL20 in airway epithelium
Authors: Carl Persson, Lena Uller
Journal: European Respiratory Journal (2015)

We read with interest the report by Zijlstra et al . [1] in which the effects of glucocorticoids possibly contributed to airway neutrophilia in asthma. This study nicely adds to the research demonstrating that corticosteroids not only inhibit the production of several inflammatory chemokines and cytokines, but also corticosteroids increase levels of certain regulatory proteins; these neutrophil-active proteins are potentially involved in inflammation or, indeed, in host defence. Hence, the data reported by Zijlstra et al . [1] may deserve attention beyond the focus given by the authors. A major challenge is to distinguish between good and bad aspects of inflammation <http://ow.ly/DAglc>
Comparative effect of disopyramide and ethmozine in suppressing complex ventricular arrhythmias by use of a double-blind, placebo-controlled, longitudinal crossover design.
Authors: C MPratt, J BYoung, M JFrancis, A ATaylor, H JNorton, LEnglish, D EMann, HKopelen, M AQuinones, RRoberts
Journal: Circulation (1984)

This placebo-controlled, double-blind, longitudinal crossover study compares the efficacy of disopyramide and ethmozine, a new investigational drug, in suppressing frequent (40 or more per hour) ventricular premature depolarizations (VPDs) in 27 patients completing a 37 day protocol. Although both drugs significantly reduced VPDs relative to placebo, ethmozine was a superior antiarrhythmic drug in ach9eving near-total abolition of VPDs (30% of patients), which was never observed during disopyramide dosing (p less than .05). At the 80% VPD reduction level, ethmozine was effective in 56% of all patients compared with an effectiveness in only 22% of patients during disopyramide therapy (p less than .05). The mean peak plasma level of ethmozine was 0.66 +/- 0.8 micrograms/ml, which significantly fell to a trough level of 0.1 +/- 0.08 micrograms/ml (p less than .001). Mean peak and trough plasma levels of disopyramide exhibited less fluctuation (2.6 +/- 0.9 micrograms/ml vs 2.2 +/- 0.9 micrograms/ml). Ethmozin...
Effects of beta-adrenergic receptor stimulation and blockade on rate-dependent atrioventricular nodal properties.
Authors: MNayebpour, MTalajic, SNattel
Journal: Circulation Research (1992)

Recent work has shown that alterations in the dynamic atrioventricular (AV) nodal response to changes in heart rate can significantly modify AV nodal function. The present study was designed to evaluate the nature and potential importance of sympathetic regulation of the rate-dependent properties of the AV node. Selective stimulation protocols and mathematical formulations were used to independently quantify AV nodal recovery, facilitation, and fatigue in 12 morphine-chloralose-anesthetized dogs. Vagal effects were prevented by bilateral vagal transection and intravenous atropine, and the sinus node was crushed to allow a broader range of pacing cycle lengths. In seven dogs with sympathetic nerves intact, beta-adrenergic receptor blockade increased the recovery time constant (tau rec) for the conduction of premature test beats from 47 +/- 2 (mean +/- SEM) msec (control) to 62 +/- 1 msec (p less than 0.001), whereas isoproterenol decreased tau rec to 38 +/- 1 msec (p less than 0.001). In addition, beta-blo...
Anchoring Technique to Access the Papillary Area in Patients With Unreachable Second Duodenal Portion
Authors: A Arrubla, N Hervas, I Rodriguez, J Carrascosa, V Jusue, C Saldaña, I Fernandez Urien, JJ Vila
Journal: Endoscopy (2021)

We present an access technique to the papillary area in patients with unreachable second dudodenal portion (SDP) without stenosis or previous surgery. A 20 mm dilatation balloon is passed over a guidewire to the proximal jejunum and is inflated to hook on a jejunal loop. The duodenoscope is introduced while forcefully retracting the balloon catheter into the working channel. The balloon works as an anchor and allows to reach the SDP. We successfully tried this technique in five patients: 3 with large hiatal hernia, 1 with duodenal deformity for previous peptic ulcer and 1 with anatomical distortion for pancreatic cancer.
The Hemoglobin A1c Level as a Progressive Risk Factor for Cardiovascular Death, Hospitalization for Heart Failure, or Death in Patients With Chronic Heart Failure : An Analysis of the Candesartan in Heart Failure : Assessment of Reduction in Mortality and Morbidity (CHARM) Program.
Authors: Gerstein, Swedberg (Karl), Carlsson (Jonas), Mcmurray
Journal: JAMA Internal Medicine (2008)
Cardiac structure growth pattern determined by echocardiography.
Authors: C LRogé, N HSilverman, P AHart, R MRay
Journal: Circulation (1978)

Using M-mode echocardiography, we measured dimensions of the ventricular walls and cavities, great vessels, and left atrium and atrioventricular valve excursions on 93 infants and children without heart disease. The data were analyzed by relating each dimension in mm to body surface area in m2 and the 90% tolerance limits for the data were calculated. The tolerance lines of the data were wider than previously recorded. At birth and maturity they were similar to the range defined as normal by studies in neonates and adults. We suggest that the tolerance lines of these normal data may be used for quantitative echocardiography in childhood.