tbuckley/cabot-search huggingface dataset:
Changes in Energy Expenditure Resulting from Altered Body Weight
Journal: New England Journal of Medicine (1995)

Background. No current treatment for obesi- ty reliably sustains weight loss, perhaps because com- pensatory metabolic processes resist the maintenance of the altered body weight. We examined the effects of ex- perimental perturbations of body weight on energy ex- penditure to determine whether they lead to metabolic changes and whether obese subjects and those who have never been obese respond similarly. Methods. We repeatedly measured 24-hour total en- ergy expenditure, resting and nonresting energy expend- iture, and the thermic effect of feeding in 18 obese sub- jects and 23 subjects who had never been obese. The subjects were studied at their usual body weight and after losing 10 to 20 percent of their body weight by underfeed- ing or gaining 10 percent by overfeeding. Results. Maintenance of a body weight at a level 10 percent or more below the initial weight was associated with a mean ( ! SD) reduction in total energy expenditure of 6 ! 3 kcal per kilogram of fat-free mass per day in the subjects who had never been obese (P  0.001) and 8 ! 5 kcal per kilogram per day in the obese subjects (P  0.001). Resting energy expenditure and nonresting energy expenditure each decreased 3 to 4 kcal per kilo- gram of fat-free mass per day in both groups of subjects. Maintenance of body weight at a level 10 percent above the usual weight was associated with an increase in total energy expenditure of 9 ! 7 kcal per kilogram of fat-free mass per day in the subjects who had never been obese (P  0.001) and 8 ! 4 kcal per kilogram per day in the obese subjects (P  0.001). The thermic effect of feeding and nonresting energy expenditure increased by approx- imately 1 to 2 and 8 to 9 kcal per kilogram of fat-free mass per day, respectively, after weight gain. These changes in energy expenditure were not related to the degree of ad- iposity or the sex of the subjects. Conclusions. Maintenance of a reduced or elevated body weight is associated with compensatory changes in energy expenditure, which oppose the maintenance of a body weight that is different from the usual weight. These compensatory changes may account for the poor long- term efficacy of treatments for obesity. (N Engl J Med 1995;332:621-8.)
Radiofrequency Ablation for the Treatment of Gastric Antral Vascular Ectasia. a Series of Three Cases in the Centre of Gastroenterology and Hepatology, Misurata, Libya
Authors: F Obide, H Maiteeg
Journal: Endoscopy (2021)

Gastric Antral Vascular Ectasia (GAVE) is an unusual cause of upper GIT bleeding. Recently, radiofrequency ablation (RFA) was used, when available, to treat GAVE gastritis with satisfactory results. Here, Halo RFA was used to treat three patients with GAVE gastritis. Each of the three patients received one or two sessions using Barrx Halo-90. All patients showed stabilization in their hemoglobin level from the first session so they no longer need blood transfusion, and the subsequent Upper GIT endoscopy showed satisfactory results. In Conclusion: treatment of moderate to severe GAVE with RFA can stabilize hemodynamic status with satisfactory results.
Effects of cholinergic nerves on cerebral blood flow in cats.
Authors: D WBusija, D DHeistad
Journal: Circulation Research (1981)

We studied the effects of parasympathetic nerves on cerebral blood flow (CBF). The greater superficial petrosal nerve, which apparently supplies cholinergic fibers to cerebral vessels and the lacrimal gland, was sectioned on one side at the internal auditory meatus in anesthetized cats. CBF was measured with 15-microns microspheres. Section of the petrosal nerve did not alter resting CBF. In addition, electrical stimulation of the distal cut end of the petrosal nerve had no effect on total CBF. In one area of the brain, the caudate nucleus, stimulation increased blood flow from 29 +/- 2 to 36 +/- 2 (mean +/- SE) ml/min per 100 g. Lacrimal gland blood flow increased from 42 +/- 7 to 198 +/- 32 ml/min per 100 g during petrosal stimulation, which indicates that the stimulus was potent. In the same experiments, CBF increased 3- to 4-fold during hypercapnia; thus, cerebral vessels were responsive to another dilator stimulus. In other experiments, petrosal nerve section did not alter the response of cerebral ve...
Heterogeneity of the action potential in isolated rat ventricular myocytes and tissue.
Authors: TWatanabe, L MDelbridge, J OBustamante, T FMcDonald
Journal: Circulation Research (1983)

The objectives of this study were to measure action potential parameters in enzyme-dissociated, adult rat ventricular myocytes stimulated at 1 Hz, to compare these measurements with those obtained from intact ventricular tissue, and to determine myocyte and tissue responses at stimulus frequencies between 0.1 and 5 Hz. Action potentials were characterized in terms of amplitude, overshoot, resting potential, duration at 25% and 75% repolarization (APD25, APD75), and Vmax. Based on statistical differences in APD25 and APD75, myocyte action potentials were classified as type I (3.1 +/- 1.0 and 21.5 +/- 3.6 msec), type II (7.4 +/- 1.1 and 38.2 +/- 6.7 msec), or type III (14.5 +/- 1.9 and 46.0 +/- 4.1 msec). Action potentials corresponding to type I were found in right ventricular endocardium and right papillary muscles, and those corresponding to types II and III in the left ventricular endocardium [apex, middle (II); base (III)] and left papillary muscles (II). Myocytes and papillary muscles responded to inc...
Effect of altered activation sequence on epicardial QRST area and refractory period in dogs.
Authors: KHanashima, IKubota, TOzawa, TShibata, MYamaki, KIkeda, SYasui
Journal: Circulation (1991)

BACKGROUNDWe investigated the effects of activation sequence on cardiac surface QRST areas and refractory periods in experiments on dogs.METHODS AND RESULTSRight and left ventricular pacings were performed, and the pacing site was altered every 6 minutes. After 4 minutes of a given pacing, 54 unipolar electrograms distributed over the entire cardiac surface were recorded. Next, refractory periods at electrode sites near pacing electrodes were measured. Paired right ventricular/left ventricular (RV/LV) pacing data were obtained six or seven times in each sample. Although the QRST isoarea maps during the two activation orders were qualitatively similar, it was recognized consistently from the right ventricle-left ventricle difference map that leads around the RV free wall had positive values and that leads around the LV free wall and apex had negative values. Compared with the same leads at RV and LV pacing, QRST areas were larger when pacing sites were near the leads. The local QRST areas of individual lea...
Effect of exercise on left ventricular mechanical efficiency in conscious dogs.
Authors: TNozawa, C PCheng, TNoda, W CLittle
Journal: Circulation (1994)

BACKGROUNDWe studied the effect of exercise (7.2 to 8.0 km/h) on the efficiency of the conversion of metabolic energy to external work or stroke work (SW) by the left ventricle (LV).METHODS AND RESULTSEnergy use was calculated from LV myocardial oxygen consumption per beat (MVO2). LV volume was calculated from orthogonal dimensions and coronary flow measured with ultrasonic flow probes. The total mechanical energy of the LV was calculated as the pressure-volume area (PVA). At rest, the MVO2-PVA point fell on the MVO2-PVA relation determined by steady-state changes in arterial pressure produced by graded infusions of phenylephrine. Exercise increased the slope (Ees) of LV end-systolic pressure-volume (PV) relation by 29%. During exercise, the MVO2-PVA point shifted to the right only slightly above the control MVO2-PVA relation by 0.007 +/- 0.005 mL O2.beat-1.100 g LV-1. Despite the increase in ventricular contractility with exercise, the PVA/MVO2 ratio was unchanged because of the marked increase in PVA. D...
A small molecule inhibitor of the chloride channel TMEM16A blocks vascular smooth muscle contraction and lowers blood pressure in spontaneously hypertensive rats
Authors: Onur Cil, Xiaolan Chen, Henry R. Askew Page, Samuel N. Baldwin, Maria C. Jordan, Pyone Myat Thwe, Marc O. Anderson, Peter M. Haggie, Iain A. Greenwood, Kenneth P. Roos, Alan S. Verkman
Journal: Kidney International (2021)
Abstract 20556: Safety and Efficacy of Intracoronary Hypoxia-PrecondItioned Bone Marrow Mononuclear Cells Administration for Acute Myocardial Infarction Patients
Authors: Xin YangHu, XinHuang, QianYang, LihanWang, JianzhongSun, HongweiZhan, JianjingLin, ZhaoxiaPu, JunJiang, YongSun, XianbaoLiu, XialjieXie, XiaYu, ZexinChen, Hung-FatTse
Journal: Circulation (2014)

IMPORTANCE: Cell therapy has been a potential approach for ST-segment elevation acute myocardial infarction (STEMI). To improve the therapeutic oucome, the safety and efficacy of hypoxia-preconditioned (H-) bone marrow mononuclear cells (BMCs) in AMI patients need further evaluation. OBJECTIVE: To investigate the safety and efficacy of H-BMCs therapy in AMI patients. DESIGN: A phase 1, randomized and blinded study (February, 2011~ March, 2012) with one-year of follow-up. SETTING: A single center for hospitalized care. PARTICIPANTS: 22 Patients with an acute ST elevation myocardial infarction were recruited and randomized to two groups: normoxia BMCs (N-, n=11) and H-BMCs (n=11). INTERVENTIONS: Intracoronary infusion of H-BMCs or N-BMCs within 5-7 days after treatment with percutaneous transluminal coronary intervention (PCI). Patients were similarly treated by a stop-flow technique through an over-the-wire balloon catheter. MAIN OUTCOMES AND MEASURES: Primary endpoint was Treatment-emergent 30-day serious...
Beneficial effects of hydralazine on rest and exercise hemodynamics in patients with chronic severe aortic insufficiency.
Authors: B HGreenberg, HDeMots, EMurphy, SRahimtoola
Journal: Circulation (1980)

We studied the effects of afterload reduction in chronic severe aortic insufficiency by measuring the hemodynamic response to oral hydralazine in 10 consecutive patients. Hemodynamics were also measured during maximal exercise in eight of these patients. At rest, hydralazine reduced pulmonary artery wedge pressure from 14 to 9 mm Hg (p less than 0.01), and increased cardiac index by 70% and stroke volume index by 35% (both p less than 0.001). Before hydralazine, pulmonary artery wedge pressure exceeded 20 mm Hg in five patients during maximal exercise; with hydralazine, at identical levels of exercise, pulmonary artery wedge pressure remained below 20 mm Hg in all patients. For the group, hydralazine reduced pulmonary artery wedge pressure from 21 to 12 mm Hg (p less than 0.05) and increased cardiac index by 31% (p less than 0.05) during exercise; changes in stroke volume index were more variable and there was no significant increase for the group, although several patients increased stroke volume substan...
Primary Aldosteronism in Diabetic Subjects With Resistant Hypertension
Authors: Ying Wai Ng, Sau Cheung Tiu, Jason Chiu Ming Ng, Hiu Yan Chan
Journal: Diabetes Care (2007)

We read with interest the article by Umpierrez et al. in a recent issue of Diabetes Care (1). Primary aldosteronism, a condition associated with suppressed renin and angiotensin levels, is known to be associated with a higher incidence of cardiovascular complications and increased mortality compared with that in patients with comparable blood pressure levels due to essential hypertension. On the other hand, activation of the renin-angiotensin system, manifesting as …
Antibodies to ADP-ATP carrier--an autoantigen in myocarditis and dilated cardiomyopathy--impair cardiac function.
Authors: KSchulze, B FBecker, RSchauer, H PSchultheiss
Journal: Circulation (1990)

The adenosine diphosphate (ADP)-adenosine triphosphate (ATP) carrier of the inner mitochondrial membrane is identified as an autoantigen in myocarditis and dilated cardiomyopathy. Sera of patients with these diseases contain autoantibodies to the ADP-ATP carrier capable of inhibiting nucleotide transport in vitro. Recently, an antibody-related infringement of energy metabolism was shown in intact perfused hearts isolated from guinea pigs immunized with the ADP-ATP carrier. A decreased cytosolic-mitochondrial difference of the phosphorylation potential of ATP was measured that originated from a reduction in mitochondrial-cytosolic nucleotide transport. Nonimmunized animals did not show these changes in energy metabolism, despite being in a comparable metabolic state and performing equal external heart work. To establish whether antibodies to the ADP-ATP carrier can also alter cardiac function, hemodynamic parameters of isolated hearts of guinea pigs that were preimmunized with the carrier protein were meas...
Right and left ventricular volume characteristics in children with pulmonary stenosis and intact ventricular septum.
Authors: MNakazawa, R AMarks, JIsabel-Jones, J MJarmakani
Journal: Circulation (1976)

Right (RV) and left ventricular (LV) volume variables were calculated in 27 patients with pulmonary stenosis (PS) during routine cardiac catheterization. These included 21 patients with isolated PS (group I) and seven studies in six patients (group II) with PS and right-to-left atrial shunt. Right and left ventricular volumes were calculated according to Simpson's rule and the area length methods respectively. In group I, right ventricular end-diastolic volume (RVEDV) was not different from normal, RVEF (0.70 +/- 0.02) was significantly higher than normal, and right ventricular stroke index (RVSI) (4.36/L/min/M2 +/- 0.23) was normal. The RVEDV/LVEDV ratio was significantly less than normal (P=0.001). Multiple regression analysis indicated that RVEDV (% of normal) decreased with both age and severity of RV outflow obstruction (r=0.77). In group II, RVEDV and RVSI were both less than normal (P less than 0.001), while RVEF was normal. LVEDV in the group was slightly higher than normal (P=0.026) while LVEF wa...
Effects of Human Growth Hormone in Men over 60 Years Old
Journal: New England Journal of Medicine (1990)

Background. The declining activity of the growth hormone-insulin-like growth factor I (IGF-I) axis with advancing age may contribute to the decrease in lean body mass and the increase in mass of adipose tissue that occur with aging. Methods. To test this hypothesis, we studied 21 healthy men from 61 to 81 years old who had plasma IGF-I concentrations of less than 350 U per liter during a six-month base-line period and a six-month treatment period that followed. During the treatment period, 12 men (group 1) received approximately 0.03 mg of biosynthetic human growth hormone per kilogram of body weight sub- cutaneously three times a week, and 9 men (group 2) re- ceived no treatment. Plasma IGF-I levels were measured monthly. At the end of each period we measured lean body mass, the mass of adipose tissue, skin thickness (epidermis plus dermis), and bone density at nine skeletal sites. Results. In group 1, the mean plasma IGF-I level rose into the youthful range of 500 to 1500 U per liter during treatment, whereas in group 2 it remained below 350 U per liter. The administration of human growth hormone for six months in group 1 was accompanied by an 8.8 percent increase in lean body mass, a 14.4 percent decrease in adipose-tissue mass, and a 1.6 percent increase in aver- age lumbar vertebral bone density (P<0.05 in each in- stance). Skin thickness increased 7.1 percent (P = 0.07). There was no significant change in the bone density of the radius or proximal femur. In group 2 there was no signifi- cant change in lean body mass, the mass of adipose tis- sue, skin thickness, or bone density during treatment. Conclusions. Diminished secretion of growth hor- mone is responsible in part for the decrease of lean body mass, the expansion of adipose-tissue mass, and the thin- ning of the skin that occur in old age. (N Engl J Med 1990; 323:1-6.)
Aortic root dilatation and mitral valve prolapse in Marfan's syndrome: an ECHOCARDIOgraphic study.
Authors: O RBrown, HDeMots, F EKloster, ARoberts, V DMenashe, R KBeals
Journal: Circulation (1975)

Echocardiographic and phonocardiographic findings in 35 patients with Marfan's Syndrome and ten patients without Marfan's or other clinically apparent connective tissue disorders but with angiographic and echocardiographic evidence of mitral prolapse are reported and compared. Echocardiography revealed aortic root dilatation and/or mitral valve prolapse in 97% of the patients with Marfan's Syndrome. Aortic root dilatation was found in 60% of this group (74% of males, 33% of females) while mitral valve prolapse was found in 91% (87% of males, 100% of females). The incidence of aortic dilatation and mitral prolapse in patients with Marfan's syndrome was essentially equal in children and adults of the same sex. None of the nine adults or one child with mitral prolapse but without evidence of Marfan's Syndrome or other clinically apparent connective tissue disorder had aortic root enlargement. Ausculatory examination and phnocardiography revealed abnormalities in 54% of the patients with Marfan's Syndrome. Ao...
Coronary surgery after recurrent myocardial infarction: progress of a trial comparing surgical with nonsurgical management for asymptomatic patients with advanced coronary disease.
Authors: R MNorris, T MAgnew, P WBrandt, K JGraham, D GHill, A RKerr, J BLowe, A HRoche, R MWhitlock, B GBarratt-Boyes
Journal: Circulation (1981)

A randomized trial of surgical vs nonsurgical management was carried out in men 60 years of age or younger who had recovered from a recurrent myocardial infarction. Of 205 patients considered, 100 had few or no symptoms and had coronary vessels favorable for bypass grafting; these patients fulfilled the trial conditions and were randomized (50 surgical and 50 nonsurgical). In 41 patients (elective nonsurgical group), randomization was not considered justifiable because of relatively unfavorable coronary anatomy or severe left ventricular dysfunction. Nineteen patients had elective surgery because of disabling angina despite full medical treatment or because of significant left main coronary stenosis. In 45 patients, coronary angiography was not undertaken because of medical contraindications or reluctance of the patient to enter the study. Actuarial survival curves (mean follow-up 4.5 years) show an annual mortality rate of 3-4% per year for all investigated patients, and no advantage for the randomized s...
Excimer laser coronary angioplasty of aorto-ostial stenoses. Results of the excimer laser coronary angioplasty (ELCA) registry in the first 200 patients.
Authors: N LEigler, BWeinstock, J SDouglas, TGoldenberg, GHartzler, DHolmes, MLeon, JMargolis, MNobuyoshi, WO'Neill
Journal: Circulation (1993)

BACKGROUNDPercutaneous transluminal coronary angioplasty (PTCA) of aorto-ostial stenosis has been associated with a lower rate of acute success, a high risk of vessel closure, and late restenosis. The purpose of this report is to document a prospective multicenter trial of excimer laser coronary angioplasty (ELCA) of aorto-ostial stenosis involving the coronary arteries and saphenous vein grafts.METHODS AND RESULTSBetween December 1989 and May 1992, 206 aorto-ostial ELCA procedures were performed on 209 stenoses in 200 patients. Canadian Cardiovascular Society class III or IV angina was present in 76%. The distribution of stenosis locations was left main coronary (LM) in 26 (12%), right coronary (RCA) in 124 (59%), and vein grafts (VG) in 59 (28%). Adjunctive PTCA was performed in 72%. Procedure success defined as < or = 50% diameter stenosis without major complications was achieved in 90% (LM, 92%; RCA, 89%, VG, 90%). Quantitative angiographic analysis documented an improvement in stenosis diameter from ...
Abstract 16308: Novel Action of Cardiomyocyte α2-Adrenergic Receptors in Reversing Angiotensin II Mediated Cardiac Hypertrophy
Authors: Santiago Reyes, Jasmina Varagic, Jessica L VonCannon, Che Ping Cheng, Carlos M Ferrario
Journal: Circulation (2018)

A transgenic rat model expressing the human angiotensinogen gene [TGR(hAGT)L1623] manifests hypertension, cardiac hypertrophy, and systolic left ventricular dysfunction. A concomitant 4-fold increa...
Effects of metabolic blockade on intracellular calcium concentration in isolated ferret ventricular muscle.
Authors: G LSmith, D GAllen
Journal: Circulation Research (1988)

Tension and intracellular free calcium concentration [( Ca2+]i) were measured in isolated ferret papillary muscles. When both anaerobic glycolysis and oxidative phosphorylation were prevented (metabolic blockade), there was a rapid decline of both developed tension and systolic [Ca2+]i signals. Subsequently, resting tension increased, and after a further delay, resting [Ca2+]i also rose. When oxidative metabolism was restarted after a period of metabolic blockade that was sufficient to elevate both resting tension and [Ca2+]i, a variable recovery of mechanical function occurred. In preparations that showed recovery, resting tension declined toward control level, and there was considerable recovery of developed tension. [Ca2+]i initially fell, but it then rose to a level similar to that at the end of the preceding period of metabolic blockade and exhibited large variations in amplitude with frequency components in the range 0.2-1 Hz. This elevated [Ca2+]i gradually declined. Arrhythmias were often present ...
Directional characteristics of action potential propagation in cardiac muscle. A model study.
Authors: L JLeon, F ARoberge
Journal: Circulation Research (1991)

Propagation of an elliptic excitation wave front was studied in a two-dimensional model of a thin sheet of cardiac muscle. The sheet model of 2.5 x 10 mm consisted of a set of 100 parallel cables coupled through a regular array of identical transverse resistors. The membrane dynamics was represented by a modified Beeler-Reuter model. We defined the charging factor (CF) to represent by a single number the proportion of input current used to charge the membrane locally below threshold and showed that CF is inversely correlated with the time constant of the foot of the action potential (tau foot) during propagation on a cable. A safety factor of propagation (SF) was also defined for the upstroke of the action potential, with SF directly correlated with the maximum rate of depolarization (Vmax) and, for cablelike propagation, with propagation velocity. Propagation along the principal longitudinal axis of the elliptic wave front is cablelike but, in comparison with a flat wave front, transverse current flow pr...
Permanent pacemaker implantation in infants, children, and adolescents. Long-term follow-up.
Authors: JBenrey, P CGillette, A TNasrallah, G LHallman
Journal: Circulation (1976)

Twenty-four patients in the pediatric age range who underwent implantation of a cardiac pacemaker for treatment of complete atrioventricular (A-V) block were followed for an average of five years (range 1-12 years). The etiology of the A-V block was surgical in 13 cases, congenital in nine, and acquired in two. Twenty patients had symptoms of cerebrovascular insufficiency and four had congestive heart failure. To date, 18 of the 24 patients studied are alive and well. Death occurred in six patients, five of whom had complex congenital heart defects, and one of whom had Refsum's disease. Death probably was caused by complete heart block despite pacemaker treatment in four patients, and congestive heart failure in two. In 18 of the 24 children with disabling complete A-V block, pacemaker therapy provided relief of symptoms and prolonged life.