tbuckley/cabot-search huggingface dataset:
Regulation of large cerebral arteries and cerebral microvascular pressure.
Authors: F MFaraci, D DHeistad
Journal: Circulation Research (1990)

Resistance of large arteries appears to be greater in the cerebral circulation than in other vascular beds. Large arteries contribute importantly to total cerebral vascular resistance and are major determinants of local microvascular pressure. Recent studies have shown that resistance of large arteries and cerebral microvascular pressure are affected by several physiological stimuli, including changes in systemic blood pressure, increases in cerebral metabolism, activity of sympathetic nerves, and humoral stimuli such as circulating vasopressin and angiotensin. Stimuli such as sympathetic stimulation and vasopressin produce selective responses of large arteries and, thereby, regulate microvascular pressure without a significant change in cerebral blood flow. These findings lead to the new hypothesis that the brain may be sensitive to changes in cerebral microvascular pressure, resulting in activation of compensatory neurohumoral mechanisms. Important changes occur in large cerebral arteries under pathophy...
The contractile state as the major determinant in the evolution of left ventricular dysfunction in the spontaneously hypertensive rat.
Authors: IMirsky, J MPfeffer, M APfeffer, EBraunwald
Journal: Circulation Research (1983)

Female spontaneously hypertensive and normotensive rats were studied at 6, 12, 18, and 24 months of age to determine which characteristics of myocardial performance herald the onset of left ventricular dysfunction. Peak ejection fraction index was derived from measurements of peak stroke volume (in vivo volume loading) and passive pressure-volume relations. The myocardial stiffness constant (km, slope of the incremental modulus-stress relation, EINC = km sigma), chamber stiffness constant (kc, slope of the chamber stiffness-pressure relation, dP/dV = kcP), and left ventricular cavitary volume-to-wall volume ratio at 10 mm Hg) were calculated from the pressure-volume data and the contractile state was assessed from the ejection fraction index-afterload relations. In the normotensive rats, the myocardial stiffness constant was not affected by age, whereas, in the spontaneously hypertensive rats, the myocardial stiffness constant remained within normal limits until 18 months, at which time a significant incr...
Two-dimensional echocardiographic evaluation of aneurysms of the descending thoracic aorta.
Authors: SIliceto, GAntonelli, GBiasco, PRizzon
Journal: Circulation (1982)

To determine the ability of two-dimensional echocardiography (2-D echo) to detect aneurysms and dissections of the descending thoracic aorta (DTA), we studied 15 patients, five with proved DTA dissections (group A) and 10 with proved aneurysms without dissection (group B), using 2-D echo in three recording positions: precordial, suprasternal and a modified apical. The DTA was visualized in 14 of 15 patients (93%); in each patient in group A, an intimal flap was recognized (in two patients only by the apical approach and in one patient by all approaches). The DTA was visualized in nine of 10 patients in group B; in each patient, the internal dimension of the DTA was enlarged (25-43 mm/m2). In one group B patient, aortic dissection was erroneously suspected because spurious echoes were present in the lumen; in another patient, 2-D echo failed to demonstrate a thrombotic stratification in the enlarged lumen. We conclude that 2-D echo using all available approaches appears to be a reliable technique for evalu...
Clinicopathological Features of Laterally Spreading Tumors Treated With Endoscopic Mucosal Resection
Authors: K Jankovic, I Jovanovic
Journal: Endoscopy (2021)

Aims Laterally spreading tumor (LST) is defined as superficial lesion at least 10 mm in diameter with lateral rather than vertical growth. They are usually underdiagnosed since they are flat making them unapparent and therefore these lesions harbor high risk for developing cancer. The study was aimed to describe the clinical and histopathological characteristics of laterally spreading tumor in our population. We also sought to measure residual lesion rates and efficacy and safety outcomes of endoscopic mucosal resection (EMR). In addition, the prevalence of synchronous colorectal lesions found in our study group was investigated.
55P Assessment of cardiovascular biomarkers for individualised treatment decision in small cell lung cancer (SCLC)
Authors: E. Gezelius, P-O. Bendahl, W. Gallo, K. Goncalves de Oliveira, L. Ek, B. Bergman, J. Sundberg, O. Melander, M. Belting
Journal: Journal of Thoracic Oncology (2021)
An Evaluation of Outcomes Following Endoscopic Balloon Dilatation of Strictures in Crohn’S Disease Patients in a Tertiary Irish Hospital
Authors: C Walker, A Carroll, E McKearney, C Deane, N Breslin, D McNamara, S O’Donnell, B Ryan, A O’Connor
Journal: Endoscopy (2021)

Aims To evaluate outcomes following endoscopic balloon dilatation (EBD) of strictures in patients with Crohn’s disease (CD).
Treating Chronic Knee Pain With Acupuncture
Authors: Lixing Lao, Wing-Fai Yeung
Journal: JAMA (2015)

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
Allosteric enhancer PD 81,723 acts by novel mechanism to potentiate cardiac actions of adenosine.
Authors: CKollias-Baker, JRuble, DDennis, R FBruns, JLinden, LBelardinelli
Journal: Circulation Research (1994)

The 2-amino-3-benzoylthiophene derivative PD 81,723 is an allosteric enhancer of agonist binding to brain A1 adenosine receptors. One aim of this study was to characterize and contrast the effects of PD 81,723 on the A1 receptor-mediated negative dromotropic and A2a receptor-mediated vasodilatory actions of adenosine and of a nonmetabolizable and unselective N6-(3-pentyl)adenosine derivative. A second aim was to determine the mechanism of action of PD 81,723. In guinea pig isolated hearts, PD 81,723 potentiated the adenosine and the N6-(3-pentyl)adenosine derivative-induced prolongations of the stimulus-to-His bundle (S-H) interval in a concentration-dependent manner. PD 81,723 (30 mumol/L) decreased the EC50 value for adenosine to prolong the S-H interval by ninefold from 7.4 +/- 1.2 to 0.8 +/- 0.1 mumol/L but did not increase the content of adenosine in cardiac effluent. PD 81,723 (30 mumol/L) increased the specific binding of the A1 agonist [3H]cyclohexyladenosine ([3H]CHA) to human atrial and guinea p...
Characteristics and Disease Severity of US Children and Adolescents Diagnosed With COVID-19
Authors: Leigh Ellyn Preston, Jennifer R. Chevinsky, Lyudmyla Kompaniyets, Amy M. Lavery, Anne Kimball, Tegan K. Boehmer, Alyson B. Goodman
Journal: JAMA Network Open (2021)

This cohort study uses data from the Premier Healthcare Database Special COVID-19 Release to assess the association of demographic and clinical characteristics with severe COVID-19 illness among hospitalized US pediatric patients with COVID-19.
Sudden Death in Myotonic Dystrophy
Authors: Ali A Sovari, Samuel C Dudley
Journal: New England Journal of Medicine (2010)

corrections any of the pancreases of the control subjects (Fig. 1F and1H), suggesting that increased intracellular glucose flux stimulates both proliferation and apoptosis pathways.Normal histologic findings in four previous cases of glucokinase-related hypoglycemia have been reported, but none of these patients underwent detailed quantitative morphometric analysis. 2-4In a previously reported case that included quantitative histologic analysis, a similar increase in the mean islet profile was confirmed (it was 2.5 times larger than that of control subjects and 8.0 to 10.0 times larger than that of patients with a K ATP -channel deficiency). 5In both that patient and our patient, the routine pathology report did not indicate any abnormality in islet size; this emphasizes the importance of quantitative morphometric analysis to determine islet size.Thus, histologic findings in infants with hyperinsulinemic hypoglycemia may differ according to the genetic cause of the condition.Furthermore, intracellular glucose flux appears to regulate proliferation and apoptosis in human beta cells; this is consistent with previous findings in murine models.Small-molecule activators of glucokinase are currently being developed for the clinical management of diabetes.Although observations in this young child with a congenital glucokinase mutation may not be directly applicable to adults with diabetes, the effect of these glucokinase activators on human beta-cell mass may be of interest.
Diminished contractile response to increased heart rate in intact human left ventricular hypertrophy. Systolic versus diastolic determinants.
Authors: C PLiu, C TTing, WLawrence, W LMaughan, M SChang, D AKass
Journal: Circulation (1993)

BACKGROUNDExperimental studies indicate that in addition to diastolic dysfunction, hypertrophied myocardium can display depressed contractile responses, particularly at rapid heart rates, compounding reserve limitations. This study tests whether such abnormalities exist in intact human subjects at physiological paced rates and, if so, whether they are linked to simultaneous rate-dependent deterioration in diastolic function.METHODS AND RESULTSTen subjects with left ventricular hypertrophy (LVH) and 8 normal control subjects were studied. Most LVH patients presented with dyspnea and/or pulmonary edema and had concentric hypertrophy. Since rapid pacing simultaneously alters cardiac filling volumes and pressures, pressure-volume relation analysis was used to better define changes in contractile response. Patients were instrumented with a conductance catheter and micromanometer for pressure-volume data recording and a balloon occluder at the right atrial-inferior vena caval junction to vary filling and thus g...
Natural orifice transluminal endoscopic surgery (NOTES)
Authors: A. Meining
Journal: Endoscopy (2012)

The initial White Paper was published in 2005 by the American Society of Gastrointestinal Endoscopy/Society of American Gastrointestinal and Endoscopic Surgeons (ASGE/SAGES) Joint Committee serving as a working group to review all issues related to natural orifice transluminal endoscopic surgery (NOTES) [2]. This Committee also created a consortium called NOSCAR (Natural Orifice Surgery Consortium for Assessment and Research), which established guidelines for research related to NOTES, organized meetings, sought funding, and guided other non-US-committees such as the EURO-NOTES. Whereas, the initial White Paper presented all issues related to research in NOTES before such a new fascinating concept could be transferred to treatment in patients, the Second White Paper summarized substantial progress achieved to date and highlighted future developments, trends, and issues in the field of NOTES [1]. Although the paper is a review article stating the opinion of NOSCAR members rather than presenting new original data, it is an essential paper on NOTES that has been published within the past year.
Stereoselective actions of thiadiazinones on canine cardiac myocytes and myofilaments.
Authors: R JSolaro, GGambassi, D MWarshaw, M RKeller, H ASpurgeon, NBeier, E GLakatta
Journal: Circulation Research (1993)

Thiadiazinones are cardiotonic agents that have potent, direct, and stereoselective actions on the myofilament response to Ca2+ in intact myocardium. Their mechanism of action is unknown. We studied the effects of racemic thiadiazinone, EMD 53998 (5-[1-(3,4-dimethoxybenzoyl)-1,2,3,4-tetrahydro-6-quinolyl]-6-meth yl-3,6- dihydro-2H-1,3,4-thiadiazin-2-one), and its enantiomers on Ca2+ signaling in myocytes, myofilaments, and myofilament proteins. Intact canine ventricular myocytes responded to the positive enantiomer, EMD 57033, with an increase in the extent of shortening during twitch contractions without increasing the peak amplitude of the Ca2+ transient. The negative enantiomer, EMD 57439, also increased the extent of shortening, but in this case there was a concentration-dependent increase in the peak amplitude of the Ca2+ transient. This is predicted from in vitro data showing that this enantiomer is a relatively potent inhibitor of phosphodiesterase activity. There was no effect of EMD 57439 on the ...
Quantification of human atrioventricular nodal concealed conduction utilizing S1S2S3 stimulation.
Authors: DWu, PDenes, R CDhingra, C RWyndham, K MRosen
Journal: Circulation Research (1976)

We studied antegrade concealed conduction of atrial extrastimuli (A2) that blocked in the atrioventricular (AV) node in eight subjects, using a third extrastimulus (A3), coupled at decreasing coupling intervals to A2. Three A1-A2 intervals were tested in each subject: late (just shorter than AV nodal effective refractory period), intermediate, and early (just longer than atrial functional refractory period). The curves relating the following variables were constructed for each A2: A1-A3, H1-H3 and A2-A3, A3-H3. The former was compared to the control A1-A2, H1-H2 curve. Concealment of A2 was demonstrated in all eight subjects at the three tested values of A1-A2. The A2-A3, A3-H3 curve allowed analysis of AV nodal conduction time (A3-H3) and AV nodal recovery time (defined as the shortest A2-A3 at which the impulse conducted to the His bundle) at identical values of A2-A3. In all subjects the timing of blocked A2 had minimal effect on both AV nodal conduction time and recovery time. In five of the eight sub...
Acidification of plasma by the red cell due to radiographic contrast materials.
Authors: M ALichtman, M SMurphy, A AWhitbeck, MPogal, E OLipchik
Journal: Circulation (1975)

The effect of water-soluble radiographic contrast material on pH when added to blood in clinical dosages in vitro or when used in vivo for diagnostic purposes was examined. Contrast material caused a reduction of blood pH. The mechanism of this occurence was found to be the balancing of the negative charge of intracellular organic anions by the extracellular anionic contrast material molecules. The normal negative potential of about 10 mV across the red cell membrane was reduced, nullified, or reversed depending on the concentration of contrast material added to blood. As the inside of the cell became more positive with respect to the outside, protons were, in effect, repelled into plasma, although the apparent exodus of protons occurs by the generation and outward diffusion of carbon dioxide. Since the acidemia is dependent on rehydration of carbon dioxide in plasma, a reaction measured in seconds, the site of injection and transit time of dye will contribute to the pH of the plasma during passage throug...
The similarity of changes in segmental contraction patterns induced by postextrasystolic potentiation and nitroglycerin.
Authors: S CKlausner, R ARatshin, J VTyberg, H ALappin, KChatterjee, W WParmley
Journal: Circulation (1976)

Despite a fundamental difference in their underlying mechanisms, both postextrasystolic potentiation (PESP) and administration of nitroglycerin (TNG) have been utilized to predict reversibility of abnormal segmental wall motion in patients with ischemic heart disease. To determine whether these interventions induce the same changes in segmental contraction pattern, we analyzed biplane ventriculograms of 14 patients who had an adequately visualized PESP beat on a basal ventriculogram as well as a post-TNG ventriculogram. Four segments in each plane were defined and the area ejection fraction of each segment was calculated for a basal sinus, PESP, and post-TNG beat. To correct for global differences in the response to PESP and TNG, we normalized each segmental ejection fraction (NSEF) by the ventricular ejection fraction for that beat and then compared the differences in NSEF from the basal value after PESP and TNG. Eleven patients demonstrated similar responses to both interventions. The three patients who...
Acute subendocardial myocardial infarction in patients. Its detection by Technetium 99-m stannous pyrophosphate myocardial scintigrams.
Authors: J TWillerson, R WParkey, F JBonte, S LMeyer, E MStokely
Journal: Circulation (1975)

Eighty-eight patients admitted to a coronary care unit with chest pain of varying etiology but without ECG evidence of an acute transmural myocardial infarction had myocardial scintigrams using technetium-99m stannour pyrophosphate (99m-Tc-PYP). Seventeen of these patients had ECG and enzymatic evidence suggestive of acute subendocardial myocardial infarction. In each of these the scintigrams were postivie demonstrating increased 99m-Tc-PYP uptake either in a faintly but diffusely positive pattern or in a well-localized strongly positive one. The remaining 71 patients did not evolve ECG or enzymatic evidence of acute myocardial infarction. In each of these patients the myocardial scintigram was negative. Thus 99m-Tc-PYP myocardial scintigrams are capable of identifying the presence of acute subendocardial myocardial infarction in patients. The absolute frequency with shich subendocardial myocardial infarction can be recognized utilizing this technique will have to be established in a larger number of pati...
Increasing oxygen delivery in surgical patients
Authors: V. Dale
Journal: JAMA (1994)

<h3>To the Editor.</h3> —Dr Boyd and colleagues<sup>1</sup>conclude from their study that "[p]erioperative increase of oxygen delivery with dopexamine hydrochloride significantly reduces mortality and morbidity in high-risk surgical patients." I do not understand why they elect to report their results in terms of an increase in oxygen delivery (Do<sub>2</sub>I), and I do not believe that their results support this interpretaton. They set out to control the arterial oxygen saturation and hemoglobin in the two groups of patients, and the results indicate that they accomplished this goal; there were no statistically significant differences between the groups in these measured variables. Cardiac index was significantly different between the two groups, as a direct effect of the intervention. Since the formula for calculating Do<sub>2</sub>I uses arterial oxygen saturation, hemoglobin, and cardiac index, the difference in Do<sub>2</sub>I between the two groups depends only on the difference in
Echocardiographic features of total anomalous pulmonary venous connection.
Authors: MPaquet, HGutgesell
Journal: Circulation (1975)

Seven patients, four months to ten years of age, with total anomalous pulmonary venous connection (TAPVC) were studied by echocardiography. The diagnosis was confirmed by cardiac catheterization, angiography, and surgery in each. The connection was to the left vertical vein in four patients, to the coronary sinus in one, to the inferior vena cava in one, and directly to the right atrium in one. All patients exhibited the echocardiographic criteria of right ventricular diastolic volume overload (RVDVO). In addition, an echo-free space was identified dorsal to the posterior wall of the left atrium. Indocyanine green dye studies done in one of the patients provided evidence that this echo-free space represents the common pulmonary venous chamber. The combination of echocardiographic evidence of RVDVO and demonstration of an echo-free space dorsal to the left atrium is strongly suggestive of TAPVC and should allow an early diagnosis in infants with this anomaly.
Diastolic collapse of the right ventricle with cardiac tamponade: an echocardiographic study.
Authors: W FArmstrong, B FSchilt, D JHelper, J CDillon, HFeigenbaum
Journal: Circulation (1982)

The value of a newly described echocardiographic sign for the detection of cardiac tamponade was retrospectively evaluated in 91 patients. M-mode echocardiograms were reviewed in 86 patients, 36 of whom had concurrent two-dimensional echocardiographic examinations; in five patients, only two-dimensional echocardiography was performed. Cardiac tamponade was clinically present in 17 patients, 14 of whom had abnormal posterior motion of the right ventricular free wall in early diastole. Two of the 17 patients with tamponade had equivocally abnormal motion and one had normal wall motion. The patient with normal wall motion was later proved to have predominantly constrictive pericardial disease. In all cases, the abnormal wall motion reverted to normal after a definitive drainage procedure. Two-dimensional echocardiography confirmed that the abnormal right ventricular wall motion represented a true collapse of the right ventricular cavity in early diastole. Of the 69 patients without clinical cardiac tamponade...
A self-sustained nanoplatform reverses TRAIL-resistance of pancreatic cancer through coactivating of exogenous and endogenous apoptotic pathway
Authors: Xianzhou Huang, Chunqing Ou, Yaqian Shu, Yan Wang, Songlin Gong, Rui Luo, Shouchun Chen, Qinjie Wu, Changyang Gong
Journal: Biomaterials (2021)
A quantitative echocardiographic study of champion childhood swimmers.
Authors: H DAllen, S JGoldberg, D JSahn, NSchy, RWojcik
Journal: Circulation (1977)

An echocardiographic evaluation of 77 members of a championship childhood swim team showed dimensional variations from normal in most athletes. Cardiac walls were thicker than the 95th percentile of normal: right ventricular anterior wall exceeded the 95th percentile in 100%, interventricular septum in 83% and left ventricular posterior wall in 91%. The left ventricular and left atrial cavities in diastole had mean values at the 50th percentile of normal but showed considerable scatter. The left ventricular cavity in systole had a mean value less than the 5th percentile of normal and also showed wide scatter. The aortic root and the aortic intercusp dimension exceeded the 95th percentile of normal in most subjects, 74% and 77%, respectively. No correlation existed between the coach's estimate of championship ability and echocardiographic wall or chamber sizes. Children who participate extensively in athletic training programs such as swimming may have echocardiograms which are quantitatively different fro...