tbuckley/cabot-search huggingface dataset:
Preparation, Premedication, and Surveillance
Authors: G D Bell
Journal: Endoscopy (2004)

The main criteria for assessing conscious sedation (perhaps now more correctly termed "moderate sedation/analgesia") continue to be patient satisfaction and comfort, short duration, amnesia, and above all, patient safety. The problems reviewed last year - including the increasing pressure on endoscopy units to perform yet more procedures, reduce costs, and achieve shorter patient turn-around times - certainly have not gone away. Studies reviewed this year suggest that although many endoscopic procedures, such as oesophagogastroduodenoscopy (OGD), colonoscopy, and endoscopic ultrasonography (EUS) can indeed be performed without intravenous sedation, many patients still prefer to be sedated. Further papers on the possible role of ultrathin endoscopes in unsedated OGD are reviewed here. A study in Italy comparing virtual computed-tomographic (CT) colonography and conventional colonoscopy suggests that unsedated colonoscopy is unlikely to meet with wide acceptance. Audits of colonoscopy in both the United States and the United Kingdom suggest that there is still a long way to go before caecal intubation rates of more than 90 % are regularly attained. The evidence suggests that some endoscopists are using larger doses of a midazolam and pethidine combination than are generally recommended (particularly in elderly patients), and sedation-related deaths are still occurring. Impressively large clinical studies, particularly those from Switzerland, on the use of propofol administered by nonanaesthetists are leading to reconsideration of the earlier view that propofol should only be used by anaesthetists. If propofol is to be used more widely and become an agent administered by endoscopists (or nursing staff), then considerable improvements in the standard of airways management will be needed. Several new studies relating to bowel-cleansing agents and the use of a carbohydrate/electrolyte "cholera mixture" to prevent the associated intravascular volume contraction have been published. Warm water is a cheap and effective way of reducing colonic spasm during colonoscopy, and intraluminal peppermint oil is a good antispasmodic in the stomach as well as the colon. Sedation should still be regarded as one part of an overall "endoscopy package". Finally, more attention needs to be given to patients' complaints regarding what are often considered by endoscopists to be "trivial complications" if the patients are to have a positive experience of their examination that will lead to them being prepared to come back a second time.
Clinical Case: ESD in Rectum With the Tunnel Formation in Submucosal Layer
Authors: A Vanyan
Journal: Endoscopy (2021)

In 66-year-old patient in rectum detected lesion 3,0x2,0 cm, 0-Is+0-IIc (Paris classification), 2b (JNET classification). The lesion was removed by ESD with the tunnel formation.Postoperative diagnosis: adenocarcinoma pT1 (sm1-250µ), G1, ly0 v0, R0. Postoperative period without complications.
The role of high-energy phosphate in norepinephrine-induced acute renal failure in the dog.
Authors: T DSinsteden, T JO'Neil, SHill, M DLifschitz, J HStein
Journal: Circulation Research (1986)

Previous studies have demonstrated that pretreatment with mannitol, furosemide, or bradykinin can attenuate the severity of norepinephrine-induced renal functional impairment. The present studies were designed to evaluate the possibility that these agents are protective, in part, by preserving cellular metabolic integrity. The renal cortex was repetitively biopsied during the course of this study, and high-pressure liquid chromatography was used to analyze the tissue content of adenine nucleotides (expressed in nanomoles per gram of wet tissue). The adenine nucleotide charge ratio (CR) and total adenine nucleotide (TAN) content were calculated as indices of cellular metabolic integrity. In addition to the above-established protective agents, phenoxybenzamine was used to evaluate a direct toxic effect of norepinephrine on renal tissue. Inulin clearance at 3 hours post infusion (expressed as a percent of control) was 7% with norepinephrine alone and, in the protected groups, 36% with bradykinin, 61% with fu...
Reversal of atherosis and sclerosis. The two components of atherosclerosis.
Authors: D HBlankenhorn, D MKramsch
Journal: Circulation (1989)

In 1904, Marchand recognized the consistent association of fatty degeneration and vessel stiffening and introduced the term  to indicate this combination. Current research is focused principally on the lipid component, but there is evidence that both aspects are reversible. Atheromatous lipids add significantly to the volume of lesions and thus contribute to vascular obstruction and end-organ damage. Reversal of atherosis has been observed in all the major species used in atherosclerosis research; rabbits, swine, dogs, chicks, pigeons, and subhuman primates. Direct evidence for reversal in humans is based on angiographic trials and is less extensive. One femoral artery and one coronary artery trial indicate that the lesions can be stabilized. CLAS, the largest angiographic trial to date, indicates that coronary lesion reversal is possible. Clinical effects of sclerosis are more subtle, and there is little evidence that sclerosis alone leads to end-organ damage. However, it should be noted...
The effectiveness of antiarrhythmic agents on early-cycle premature ventricular complexes.
Authors: R JKrone, J PMiller, R EKleiger, K WClark, G COliver
Journal: Circulation (1981)

Twelve patients completed a double-blind, crossover antiarrhythmic drug trial in which 300 mg of quinidine, 500 mg of procainamide, 100 mg of phenytoin, or placebo was given four times daily on subsequent weeks. Analysis of 24-hour Holter tapes with a computerized analysis system (Argus/H) permitted accurate counting of premature ventricular complexes (PVCs) subclassified according to coupling interval. No antiarrhythmic agent demonstrated a significant overall reduction in the number of PVCs, but both quinidine and procainamide showed a statistically significant (p less than 0.05) reduction of PVCs with coupling intervals less than 400 msec. This effect was noted both in isolated PVCs (quinidine only) and in PVCs that were part of a couplet or run (both drugs). These findings demonstrate that clinically important effects of procainamide and quinidine can occur in the absence of an overall reduction in the number of PVCs.
Characterization of the spatial distribution of late ventricular potentials by body surface mapping in patients with ventricular tachycardia.
Authors: GFaugère, PSavard, R ANadeau, DDerome, MShenasa, P LPage, RGuardo
Journal: Circulation (1986)

Low-level activity at the end of the QRS complex was analyzed from 63 thoracic leads in 15 normal subjects and in 21 patients with ventricular tachycardia (VT). The latter had old myocardial infarction and no conduction disturbances and had not been receiving antiarrhythmic drugs. In both normal subjects and patients with VT, isopotential maps of the time-averaged and filtered (25 Hz high-pass) electrocardiograms during the terminal portion of the QRS were dipolar, i.e., they showed single positive and negative regions. For patients with VT, the extrema were either distant, with one over the precordial area and the other over the back, or close together in the precordial region. In 10 patients, maps recorded after administration of antiarrhythmic drugs remained the same while QRS duration was prolonged. In six patients, maps recorded before antiarrhythmic surgery showed distant extrema for septal or posterobasal VT sites of origin and close extrema for anterior or posteroapical sites. Generally, QRS durat...
Immunolocalization and expression of functional and nonfunctional cell-to-cell channels from wild-type and mutant rat heart connexin43 cDNA.
Authors: BDunham, SLiu, STaffet, ETrabka-Janik, MDelmar, RPetryshyn, SZheng, RPerzova, M LVallano
Journal: Circulation Research (1992)

The carboxyl terminal cytoplasmic domain of distinct gap junction proteins may play an important role in assembly of functional channels as well as differential responsiveness to pH, voltage, and intracellular second messengers. Oligonucleotide-directed site-specific mutagenesis in a paired Xenopus laevis oocyte expression system was used to examine the expression of mRNAs encoding wild-type and carboxyl terminal mutant connexin43 (Cx43) proteins. Oocytes were stripped, injected with mRNA or distilled water (dH2O), preincubated for 16-20 hours, and then paired for 5-10 hours; this process was followed by electrophysiological recording using the dual voltage-clamp technique. Initial experiments compared the relative junctional conductances (Gjs) in oocyte pairs expressing Cx43 (382 amino acid residues) and two truncated mutants lacking most or a portion of the cytoplasmic carboxyl terminal. The shortest mutant (M241) contained 240 amino acid residues and was devoid of all phosphorylatable serine residues i...
Intramyocardial platelet aggregation in patients with unstable angina suffering sudden ischemic cardiac death.
Authors: M JDavies, A CThomas, P AKnapman, J RHangartner
Journal: Circulation (1986)

A specific search for intramyocardial platelet aggregates was made in 90 patients who died suddenly of ischemic heart disease. Platelet aggregates in small intramyocardial vessels were found in 27 (30%). There was a significant difference (p less than .05) in the incidence of platelet aggregates in patients with chest pain of recent onset (unstable angina) before death (16/36, 44.4%) and that in those without it (11/54, 20.4%). Multifocal microscopic necrosis with involvement of the full thickness of the ventricular wall, including the subpericardial zone, was significantly more common (p = less than .005) in the patients with platelet emboli (55.6% vs 12.7%). With one exception, aggregates were confined to the segment of myocardium immediately downstream of a major epicardial coronary artery containing an atheromatous plaque that had undergone fissuring and on which mural thrombus had developed. The results support the view that platelet aggregates in the myocardium represent an embolic phenomenon and ar...
In vivo determination of the force of leukocyte-endothelium adhesion in the mesenteric microvasculature of the cat.
Authors: S DHouse, H HLipowsky
Journal: Circulation Research (1988)

Quantitative estimates of the force of adhesion between leukocytes and endothelium were obtained from in vivo hemodynamic measurements in small venules of cat mesentery during topical application of the chemotactic compound N-formyl-methionyl-leucyl-phenylalanine (FMLP). Simultaneous measurements of upstream to downstream pressure drop, red cell velocity, microvessel hematocrit, and vessel diameter and length permitted application of the principles of momentum conservation to calculate the forces acting upon a leukocyte during adhesion to the endothelium. For venules ranging in diameter from 23 to 49 micron, the ratio of force (acting in the vessel axial direction) to wall shear stress on the endothelium fell from 14.6 X 10(-6) in small venules to 2.3 X 10(-6) dynes per dyne/cm2 in large venules; reflecting the larger pressure drops and forces attendant to greater lumen obstruction in the smaller venules. The equilibrium force representative of a balance between fluid shear stresses on the leukocyte and t...
The physiologic effects of digoxin under steady-state drug conditions in newborn and adult sheep.
Authors: WBerman, JMusselman, RShortencarrier
Journal: Circulation (1980)

The physiologic response to the chronic administration of digoxin was studied in 12 adult and 13 newborn sheep. Vascular pressures, cardiac output, isovolumic contraction phase indexes and systolic time intervals were measured before and after 2 weeks of digoxin therapy. Physiologic measurements were correlated with drug levels in plasma and myocardium. Resting myocardial function in newborns exceeded that in ewes. In ewes, the heart rate decreased from 98 to 74 beats/min, the preejection period (PEP) decreased from 76 to 57 msec, the ratio of PEP to left ventricular ejection time (LVET) decreased from 0.323 to 0.223 and dP/dt max increased from 2415 to 3460 mm Hg . sec-1 as plasma concentrations of digoxin increased to a mean of 1.8 ng/ml. Although the final steady-state plasma concentration of digoxin in newborn lambs averaged 1.7 ng/ml, cardiac output, PEP, PEP/LVET and dP/dt max did not change significantly from baseline values. These studies suggest that developmental differences in the physiologic r...
Relative impact of targeted versus populationwide cholesterol interventions on the incidence of coronary heart disease. Projections of the Coronary Heart Disease Policy Model.
Authors: LGoldman, M CWeinstein, L WWilliams
Journal: Circulation (1989)

We used the Coronary Heart Disease Policy Model, a state-transition computer simulation, to assess the absolute and relative effects of two different national cholesterol interventions: a targeted program to identify and treat all individuals with elevated serum cholesterol levels (greater than or equal to 250 mg/dl) versus a populationwide program to reduce everyone's serum cholesterol level. Based on the assumptions inherent in our model, which uses the Framingham Heart Study coefficients, we estimate the targeted program would reduce projected coronary heart disease absolute incidence by 8-10% in men ages 35-54 years and by 1-4% in men ages 55-74 years. Our model suggests that similar reductions in coronary heart disease incidence could be achieved by a 10 mg/dl populationwide reduction in serum cholesterol levels. In women, the targeted program would yield greater relative and absolute benefits and would be equivalent to a approximately 23 mg/dl populationwide reduction in serum cholesterol. We conclu...
Increasing pericardial effusion in cardiac transplant recipients.
Authors: H AValantine, S AHunt, RGibbons, M EBillingham, E BStinson, R LPopp
Journal: Circulation (1989)

Although pericardial effusion after cardiac surgery is frequent and usually benign, its etiology and prognosis after cardiac transplantation are unknown. During 1 year (1985-1986), 12 of our current transplant population (total, 189) developed moderate or large pericardial effusions confirmed by two-dimensional echocardiography. These effusions occurred within 1 month of transplantation in 10 patients and at 3 months and 4.5 years in the other two. Pericardiocentesis was performed because of clinical evidence of increasing effusions in eight patients, with demonstrable hemodynamic compromise secondary to tamponade in five. Pericardial fluid was sterile in all but one. Endomyocardial biopsy at the time of increasing effusion revealed moderate acute rejection in five patients, mild rejection in three, and no rejection in four. All three patients with mild rejection had moderate acute rejection on subsequent biopsy performed within 7 days. In two of the four with no rejection, repeat biopsy within 5 days sho...
Heart rate spectral analysis, cardiac norepinephrine spillover, and muscle sympathetic nerve activity during human sympathetic nervous activation and failure.
Authors: B AKingwell, J MThompson, D MKaye, G AMcPherson, G LJennings, M DEsler
Journal: Circulation (1994)

BACKGROUNDAlthough heart rate variability (HRV) at 0.1 Hz has been proposed as a noninvasive clinical measure of cardiac sympathetic nerve firing, this premise has not been sufficiently validated by comparison with techniques such as microneurography and the measurement of norepinephrine spillover from the heart that more directly reflect presynaptic sympathetic activity.METHODS AND RESULTSWe compared the three techniques under conditions of effective cardiac sympathetic denervation, pure autonomic failure (n = 4), dopamine beta-hydroxylase deficiency (n = 1), and after cardiac transplantation (n = 9) as well as in the context of sympathetic nervous activation in cardiac failure (n = 15) and with aging (n = 10). Age-matched comparisons were made in each case with healthy individuals drawn from a pool of 52 volunteers. In pure autonomic failure and early after transplantation, cardiac norepinephrine spillover was negligible, and HRV was low. Late after transplantation, however, cardiac norepinephrine spill...
Regulation of insulin-like growth factor I receptors on vascular smooth muscle cells by growth factors and phorbol esters.
Authors: J JVerveris, LKu, PDelafontaine
Journal: Circulation Research (1993)

Insulin-like growth factor I (IGF I) is an important mitogen for vascular smooth muscle cells. To characterize regulation of vascular IGF I receptors, we performed radioligand displacement experiments using rat aortic smooth muscle cells (RASMs). Serum deprivation for 48 hours caused a 40% decrease in IGF I receptor number. Exposure of quiescent RASMs to platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), or angiotensin II (Ang II) caused a 1.5-2.0-fold increase in IGF I receptors per cell. After FGF exposure, there was a marked increase in the mitogenic response to IGF I. IGF I downregulated its receptors in the presence of platelet-poor plasma. Stimulation of protein kinase C (PKC) by exposure of quiescent RASMs to phorbol 12-myristate 13-acetate caused a biphasic response in IGF I binding; there was a 42% decrease in receptor number at 45 minutes and a 238% increase at 24 hours. To determine the role of PKC in growth factor-induced regulation of IGF I receptors, we downregulated PKC ...
Regional myocardial perfusion during atrial pacing in patients with coronary artery disease.
Authors: D HSchmidt, M BWeiss, W JCasarella, D LFowler, R RSciacca, P JCannon
Journal: Circulation (1976)

Regional myocardial perfusion (RMP) was measured with 133xenon and a multiple-crystal scintillation camera at rest and during atrial pacing in 24 patients with normal coronary arteriograms or less than 50% lesions, Group I, and in 24 with significant (greater than 50% lesions) left coronary artery disease (CAD), Group II. Pacing induced increases in the double product (DP) of heart rate and systolic blood pressure, an index of myocardial oxygen consumption, were not different for Groups I and II. In Group I average mean LV perfusion rate was subnormal at rest but rose from 49 to 73 ml/100 g-min during pacing to 150/min without angina. A response index (RI), (deltaMP X 10(3)/deltaDP), averaged 2.93. Twenty patients in Group II developed angina during pacing. The average mean LV perfusion rose less than in Group I, from 48 to 64 ml/100 g-min (P less than 0.05) and the average RI, 1.76, was lower (P less than 0.01). In 19 of these patients, average RMP distal to the major coronary lesion increased from 46 to...
Adaptation of canine saphenous veins to grafting. Correlation of contractility and contractile protein content.
Authors: C LSeidel, R MLewis, RBowers, R DBukoski, H SKim, J CAllen, CHartley
Journal: Circulation Research (1984)

Saphenous veins are used extensively to replace stenotic coronary arteries. However, the contractile and biochemical adaptations of grafted veins are unknown. The three purposes of this work were to characterize the contractile properties of grafted veins, to determine whether altered contractile characteristics were associated with quantitative changes in actin, myosin and collagen, and to determine which changes were associated with the surgical procedure and which with placement in the arterial circulation. Canine saphenous veins were removed and returned to their original location (venous autograft), while others were used to replace a segment of femoral artery (arterial graft). The grafts were removed 1, 4, and 8 weeks later and compared with the contralateral saphenous vein. Both graft types exhibited an increase in sensitivity to norepinephrine but not to potassium chloride. The venous autograft exhibited a reversible reduction in myosin content and in maximum contractile response (force/cross-sect...
Enhanced phosphodiesteratic breakdown and turnover of phosphoinositides during reperfusion of ischemic rat heart.
Authors: HOtani, M RPrasad, R MEngelman, G ACordis, D KDas
Journal: Circulation Research (1988)

In this study, we examined phosphoinositide metabolism during ischemia and reperfusion using an isolated and perfused rat heart. When myocardial phosphoinositides were prelabeled with [3H]inositol, reperfusion after 30 minutes of normothermic global ischemia resulted in significant accumulations of radiolabeled inositol phosphate, inositol bisphosphate, and inositol trisphosphate. Isotopic incorporation of [3H]inositol into phosphatidylinositol, phosphatidylinositol-4-phosphate, and phosphatidylinositol-4,5-bisphosphate was increased significantly in the heart reperfused with [3H]inositol after 30 minutes of ischemia compared with that perfused with [3H]inositol after 30 minutes of nonischemic perfusion. However, isotopic incorporation of [3H]glycerol into diacylglycerol, phosphatidic acid, and all of the three phosphoinositides was diminished in the reperfused hearts. Reperfusion of the ischemic heart prelabeled with [14C]arachidonic acid resulted in significant increases in [14C]diacylglycerol and [14C]...
Mortality after Allogeneic Stem Cell Transplantation Associates with Gene Polymorphisms in CD40L and Thrombomodulin in the Absence of Statins
Authors: Thomas Luft, Sivaramakrishna P. Rachakonda, Hao Dai, Olaf Penack, Olga Blau, Igor Wolfgang Blau, Aleksandar Radujkovic, Carsten Müller-Tidow, Peter Dreger, Rajive Kumar
Journal: Blood (2017)
Postextrasystolic compliance of the left ventricle.
Authors: W HGaasch, O HBing, J SCole, H GHanley
Journal: Circulation (1977)

The effects of a single premature contraction (PC) on left ventricular diastolic distensibility was studied in man, in the conscious chronically instrumented dog, and in the isolated (isovolumic) blood perfused dog heart. In the isolated dog heart at a constant volume, there was no difference in end-diastolic pressure when control diastolic pressure was compared to that following a PC. In man and conscious dogs, there was no difference between the overall pressure-volume or pressure-length plots when control diastolic data were compared to data from the diastole immediately following a PC (no change in the modulus of chamber stiffness). In the intact circulation of man dog, increased filling during the post PC pause causes the ventricle to operate higher on the steep (stiffer) portion of its pressure-volume or pressure-length curve (decrease in preload-dependent compliance). Thus, although a PC does not alter the modulus of chamber stiffness, a preload-dependent change in compliance may occur during post ...
The phase-dependency of the cardiac chronotropic responses to vagal stimulation as a factor in sympathetic-vagal interactions.
Authors: TYang, M NLevy
Journal: Circulation Research (1984)

We determined the effects of the timing of repetitive bursts of vagal stimulation on the positive chronotropic responses of the heart to trains of cardiac sympathetic nerve stimulation in open-chest anesthetized dogs. Trains of sympathetic stimulation alone, at frequencies of 2 and 4 Hz, decreased the cardiac cycle length by 176 +/- 19 msec (mean +/- SE) and 190 +/- 22 msec, respectively. When bursts of vagal stimuli were given once each cardiac cycle and they were placed at their least effective time in the cycle, sympathetic stimulation at frequencies of 2 and 4 Hz decreased cardiac cycle length by only 107 +/- 8 and 120 +/- 8 msec, respectively. However, when the bursts of vagal stimuli were delivered at their most effective time in each cycle, the same levels of sympathetic stimulation elicited much larger reductions in cardiac cycle length (285 +/- 32 and 330 +/- 32 msec, respectively). Therefore, the effects of sympathetic stimulation were significantly attenuated by the vagal stimuli when the vagal...