tbuckley/cabot-search huggingface dataset:
Endothelin-1-induced vasoconstriction in humans. Reversal by calcium channel blockade but not by nitrovasodilators or endothelium-derived relaxing factor.
Authors: WKiowski, T FLüscher, LLinder, F RBühler
Journal: Circulation (1991)

The vascular effects of endothelin-1 (ET) in humans were investigated by brachial artery infusions of ET into 25 healthy volunteers. Forearm blood flow increased from a mean +/- SD value of 2.3 +/- 1.5 to 2.5 +/- 1.5 ml/min/100 ml forearm tissue (n = 25, p less than 0.05) in response to low dose (0.5 ng/min/100 ml forearm tissue) ET infusion and decreased to 1.78 +/- 1.3 and 1.1 +/- 0.9 ml/min/100 ml forearm tissue (p less than 0.001) during higher dosages (25 and 50 ng/min/100 ml forearm tissue). Sodium nitroprusside (0.6 micrograms/min/100 ml forearm tissue, n = 6), acetylcholine (16 micrograms/min/100 ml forearm tissue, n = 7), nifedipine (6 micrograms/min/100 ml forearm tissue, n = 6), and verapamil (80 micrograms/min/100 ml forearm tissue, n = 6) were infused alone and in combination with ET to evaluate the interactions between ET-induced vasoconstriction and stimulation of vascular muscle cyclic GMP levels by sodium nitroprusside, release of endothelium-derived relaxing factor by acetylcholine, and ...
Rapid electrophysiological changes leading to arrhythmias in the aerobic rat heart. Photosensitization studies with rose bengal-derived reactive oxygen intermediates.
Authors: D JHearse, YKusama, MBernier
Journal: Circulation Research (1989)

The objective of this study was to determine whether reactive oxygen intermediates (e.g., singlet oxygen and the superoxide radical) can rapidly induce electrophysiological disturbances leading to the genesis of arrhythmias, even in the absence of ischemia and reperfusion. Rat hearts (n = 6 per group) were perfused aerobically at 37 degrees C for 10 minutes without rose bengal and for 5 minutes with rose bengal (250 nmol/l), during which time no changes in coronary flow or heart rate were observed. Hearts were then uniformly illuminated for 20 minutes with green light (530-590 nm) from 200 fiber optic cables. With light and without rose bengal, or vice versa, all hearts remained stable. However, in the illuminated rose bengal group, electrophysiological changes (inversion of the terminal portion of the T wave and an increase in Q-T interval) were observed within 11.8 +/- 2.1 seconds (i.e., less than 60 beats). All hearts exhibited ventricular premature beats (within 2.2 +/- 0.7 minutes) and ventricular ta...
Duration of ischemia is vital for collateral development: repeated brief coronary artery occlusions in conscious dogs.
Authors: MMohri, HTomoike, MNoma, TInoue, KHisano, MNakamura
Journal: Circulation Research (1989)

The effects of two types of repeated transient coronary artery occlusions on collateral development were examined in chronically instrumented, conscious dogs. A 2-minute coronary occlusion at 32-minute intervals (group 1, n = 11) or a 15-second occlusion at 4-minute intervals (group 2, n = 7) were repeated day and night without interruption. In both groups, the total duration of coronary occlusions each day was the same (90 minutes). Before and after repetitive occlusions of either group, effects of transient 2-minute coronary occlusion on regional segment shortening in the ischemic area were examined to assess the functional state of the collateral vessels. In group 1, systolic segment shortening in the area rendered ischemic was reduced to -97.8 +/- 17.7% of the preocclusive control value during 2 minutes of coronary occlusion. After 125-478 repetitive occlusions (3-11 days), the degree of hypokinesia during the 2-minute occlusion was significantly improved to -0.6 +/- 4.6% of the preocclusive value (p ...
Effects of aging on changing arterial compliance and left ventricular load in a northern Chinese urban community.
Authors: A PAvolio, S GChen, R PWang, C LZhang, M FLi, M FO'Rourke
Journal: Circulation (1983)

Pulse wave velocity (PWV) was measured by means of transcutaneous Doppler techniques in the aorta, right arm, and right leg of 480 normal subjects of both sexes in urban Beijing, China (age range 3 to 89 years, mean age 41 +/- 20.8 SD); supine blood pressure was recorded in the brachial artery of each subject with standard sphygmomanometric procedures. Serum cholesterol was determined in a subgroup of 79 subjects (age 17 to 85 years, mean 47 +/- 26 SD). PWV (y in cm/sec) was found to vary with age (x, years) at each of the three locations according to the following regression equations: aorta, y = 9.2x + 615, r = .673 (p less than .001); right arm, y = 4.8x + 998, r = .453 (p less than .001); right leg, y = 5.6x + 791, r = .630 (p less than .001). Systolic, diastolic, mean, and pulse pressures were found to increase with age. PWV also increased with mean supine blood pressure but was not related to serum cholesterol (average 4.49 +/- 0.11 [SEM], mmol/l). Compared with that of Western populations, serum ch...
Beneficial effects of pimobendan on exercise tolerance and quality of life in patients with heart failure. Results of a multicenter trial. The Pimobendan Multicenter Research Group.
Authors: S HKubo, SGollub, RBourge, PRahko, FCobb, MJessup, SBrozena, MBrodsky, PKirlin, JShanes
Journal: Circulation (1992)

BACKGROUNDThis multicenter trial was conducted to determine the efficacy and safety of pimobendan, an inotropic agent with calcium-sensitizing properties and activity as a phosphodiesterase inhibitor, in patients with heart failure.METHODS AND RESULTSOne hundred ninety-eight ambulatory patients with symptoms of moderate to severe heart failure despite therapy with digitalis and diuretics with or without a single vasodilator were randomly assigned to receive either placebo (n = 49) or pimobendan (n = 149) in a double-blind fashion for 12 weeks. A dose range of pimobendan was used including 2.5 (n = 49), 5 (n = 51), or 10 mg/day (n = 49). One hundred fifty-eight (80%) patients were taking a converting enzyme inhibitor (CEI) and 28 (14%) patients were taking a non-CEI vasodilator. At end point, the 5-mg dose of pimobendan significantly increase exercise duration compared with placebo (121.6 +/- 19.1 seconds, p less than 0.001), whereas the 10-mg dose produced an increase of borderline significance (81.1 +/- ...
Systemic Lupus Erythematosus
Authors: Lester S. King
Journal: JAMA (1961)

The author declares that systemic lupus erythematosus should be considered one of the "great imitators," along with syphilis, tuberculosis, or malaria. The variable course and the widely diverse manifestations can cause difficulty in achieving a correct diagnosis. With this in mind Dr. Larson discusses the disease in systematic fashion, drawing chiefly on a series of 200 cases clinically so diagnosed at the Presbyterian Hospital in New York, over the past 20 years. He takes up, by organs, the various clinical manifestations which the disease may display, and offers brief illustrative case histories. The orientation is essentially clinical, and there is only scant mention of anatomical findings. However, there is a good discussion of the laboratory features of the disease, especially of the LE cell factor. There is a bibliography of 229 titles. The book, attractively published, is in no sense a definitive analysis of our knowledge on this disease, but
Exercise testing soon after myocardial infarction.
Authors: WMarkiewicz, NHouston, R FDeBusk
Journal: Circulation (1977)

Forty-six men under age 70, without clinical congestive heart failure or unstable angina pectoris, performed treadmill tests 3, 5, 7, 9 and 11 weeks after myocardial infarction. Patients were more frequently able to perform moderate exertion (2 mph, 14% grade) at 7 and 11 weeks than at 3 weeks following infarction. Ischemic ST-segment depression, usually unaccompained by angina pectoris, occurred in 45% of patients and was associated with a significantly increased incidence of subsequent coronary events. The presence of exercise-induced ventricular ectopic activity provided little independent prognostic information. No serious complications occurred in 210 tests. Exercise testing soon after myocardial infarction provides objective information concerning the capacity to resume physical activity, including return to work. Two tests, at 3-5 weeks and at 7-11 weeks, appear to provide most of the information contined in five tests performed during this time.
State Medical Board Recommendations for Stronger Approaches to Sexual Misconduct by Physicians
Authors: Patricia A. King, Humayun J. Chaudhry, Mark L. Staz
Journal: JAMA (2021)

This Viewpoint discusses recommendations adopted by the US Federation of State Medical Boards (FSMB) to guide state boards on how to respond to reports of sexual misconduct by physicians toward patients, including harassment and abuse.
Enhancement of rabbit cardiac sodium channels by beta-adrenergic stimulation.
Authors: J JMatsuda, HLee, E FShibata
Journal: Circulation Research (1992)

Voltage-dependent sodium channels from a variety of tissues are known to be phosphorylated by the cAMP-dependent protein kinase, protein kinase A. However, the functional significance of sodium channel phosphorylation is not clearly understood. Using whole-cell voltage-clamp techniques, we show that sodium currents (INas) in rabbit cardiac myocytes are enhanced by isoproterenol (ISO). This enhancement of INa by ISO 1) is holding potential dependent, 2) can be mimicked by forskolin and dibutyryl cAMP, and 3) is accompanied by an increase in the rate of Na+ channel inactivation. In single-channel, inside-out patch experiments, the catalytic subunit of protein kinase A also enhances INa and increases the rate of inactivation, suggesting that cardiac Na+ channel phosphorylation may be physiologically important. Addition of the protein kinase A inhibitor to the pipette solution in whole-cell experiments blocks the stimulatory effect of forskolin without blocking the effect of ISO, suggesting that ISO also enha...
Post-Polypectomy Followup Recommendations Without Pathology, Is it Possible? Preliminary Results
Authors: N Abu Freha, M Abu Tailakh, O Abu-Freha, A Estis-Deaton, J Elkrinawi, O Alamour, O Etzion
Journal: Endoscopy (2021)

Aims Appropriate post-polypectomy surveillance recommendations are an important performance measure for colonoscopy. We aimed to determine the rate of recommendations change due to the pathology results of villous component or high-grade dysplasia in 1-4 polyps smaller than 10 mm.
Evidence that method of use, dose and duration of treatment with benzoyl peroxide and tetracycline determines response of acne.
Authors: Marsden
Journal: Journal of the Royal Society of Medicine (1985)

Abstract
Treatment of acne prior to referral was recorded retrospectively in 72 patients alleged to have responded inadequately; 60% had used benzoyl peroxide (BP) but most applied it to lesions only. Although 86% had used tetracycline, most did not take it correctly for maximum absorption and took less than 1 g/day. Most patients used both drugs for less than three months. Eight-two patients referred because of inadequate response were treated with: (I) 5% benzoyl peroxide (BP) (23 patients); (II) 5% BP and 0.5 g/day oxytetracycline (OTC) (24 patients); (III) 5% BP and 1 g/day OTC (18 patients); (IV) 5% BP and 1.5 g/day OTC (17 patients). BP was applied incrementally from 30 min up to 8-10 hours daily to the entire area affected and OTC taken as a single morning dose. Median grade of severity (0-10 analogue scale) fell by 2 in Groups I and II (P less than 0.05), by 2.5 in Group III (P less than 0.05) and by 3 in Group IV (P less than 0.05); number of lesions fell by 56% +/- 7% (s.e.), (P less than 0.001) 70% +/- less than 10% (P less than 0.001), 75% +/- 8% (P less than 0.001) and 78% +/- 10% (P less than 0.001) respectively and treatment was well tolerated. Thus, although effective drugs are frequently prescribed in acne, method of use, dose and duration are likely to determine response.
Presence of viremia during febrile neutropenic episodes in patients undergoing chemotherapy for malignant neoplasms
Authors: Klára Obrová, Silke Grumaz, Marlene Remely, Stefan Czurda, Isabella Krickl, Susanne Herndlhofer, Karoline V. Gleixner, Wolfgang R. Sperr, Lisa Größlinger, Tijana Frank, Nuno Andrade, Teresa Egger‐Matiqi, Christina Peters, Gernot Engstler, Michael Dworzak, Andishe Attarbaschi, Martine van Grotel, Marry M. van den Heuvel‐Eibrink, Ivan S. Moiseev, Yuliya Rogacheva, Ludmilla Zubarovskaya, Natalia Zubarovskaya, Herbert Pichler, Anita Lawitschka, Elisabeth Koller, Felix Keil, Peter Valent, Kai Sohn, Thomas Lion
Journal: American Journal of Hematology (2021)

The importance of viral infections as a leading cause of morbidity and mortality is well documented in severely immunosuppressed patients undergoing allogeneic stem cell transplantation. By contrast, viral infections generally receive less attention in patients with malignant disorders undergoing chemotherapy, where the onset of neutropenic fever is mostly associated with bacterial or fungal infections, and screening for viral infections is not routinely performed. To address the occurrence of invasive viral infections in a clinical setting commonly associated with less pronounced immunosuppression, we have prospectively screened 237 febrile neutropenic episodes in pediatric (n = 77) and adult (n = 69) patients undergoing intensive chemotherapy, primarily for treatment of acute leukemia. Serial peripheral blood specimens were tested by RQ-PCR assays for the presence and quantity of the clinically relevant viruses CMV, EBV, HHV6 and HAdV, commonly reactivated in highly immunocompromised patients. Viremia was documented in 36 (15%) episodes investigated, including the detection of HHV6 (n = 14), EBV (n = 15), CMV (n = 6), or HAdV (n = 1). While low or intermediate levels of viremia (<104 virus copies/mL) were commonly associated with bacterial or fungal co-infection, viremia at higher levels (>104 copies/mL) was documented in patients without evidence for other infections, raising the possibility that at least in some instances the onset of fever may have been attributable to the virus detected. The observations suggest that viral infections, potentially resulting from reactivation, might also play a clinically relevant role in patients receiving chemotherapy for treatment of malignant neoplasms, and routine screening for viremia in this clinical setting might be warranted.
Specific populations of basal ganglia output neurons target distinct brain stem areas while collateralizing throughout the diencephalon
Authors: Lauren E. McElvain, Yuncong Chen, Jeffrey D. Moore, G. Stefano Brigidi, Brenda L. Bloodgood, Byung Kook Lim, Rui M. Costa, David Kleinfeld
Journal: Neuron (2021)

Basal ganglia play a central role in regulating behavior, but the organization of their outputs to other brain areas is incompletely understood. We investigate the largest output nucleus, the substantia nigra pars reticulata (SNr), and delineate the organization and physiology of its projection populations in mice. Using genetically targeted viral tracing and whole-brain anatomical analysis, we identify over 40 SNr targets that encompass a roughly 50-fold range of axonal densities. Retrograde tracing from the volumetrically largest targets indicates that the SNr contains segregated subpopulations that differentially project to functionally distinct brain stem regions. These subpopulations are electrophysiologically specialized and topographically organized and collateralize to common diencephalon targets, including the motor and intralaminar thalamus as well as the pedunculopontine nucleus and the midbrain reticular formation. These findings establish that SNr signaling is organized as dense, parallel outputs to specific brain stem targets concurrent with extensive collateral branches that encompass the majority of SNr axonal boutons.
Developmental changes in contractile protein adenosine 5'-triphosphatase in the rabbit heart.
Authors: TNakanishi, MNagae, ATakao
Journal: Circulation Research (1986)

This study was designed to investigate developmental changes in contractile protein adenosine 5'-triphosphatase in the rabbit heart. Myofibrils and myosin were isolated from ventricular muscles from the fetal, newborn, and adult rabbits. Actin and troponin-tropomyosin complex were isolated from the adult skeletal muscle. Myofibrillar (actomyosin) adenosine 5'-triphosphatase measured at low ionic strength increased with development. In contrast, myofibrillar calcium adenosine 5'-triphosphatase at high ionic strength was the greatest in the newborn and the lowest in the adult. Myosin calcium adenosine 5'-triphosphatase and actin-activated myosin adenosine 5'-triphosphatase were also the greatest in the newborn and the lowest in the adult. The relative proportion of myosin isozyme V1 was the greatest in the newborn and the lowest in the adult. The addition of troponin-tropomyosin complex stimulated myosin adenosine 5'-triphosphatase in the presence of calcium in the adult, but not in the newborn and fetus. A...
Contrast M-mode echocardiography in diagnosis of atrial septal defect in acyanotic patients.
Authors: GKronik, JSlany, HMoesslacher
Journal: Circulation (1979)

Contrast echocardiograms during normal quiet respiration and during the Valsalva maneuver were performed in 15 patients with atrial septal defect (ASD) by injecting saline solution into an antecubital vein. Contrast shunting (the appearance of contrast echoes in the left heart) was observed not only in four patients with severe pulmonary hypertension (group 2), but also in 11 patients with uncomplicated ASD (group 1). Contrast shunting was prominent in all group 2 patients. In group 1, contrast shunting was sometimes subtle and difficult to recognize, but at other times was very obvious and similar to the findings in group 2. Contrast shunting was generally more pronounced during the Valsalva maneuver than during normal respiration, although there were exceptions. The amount of contrast appearing in the left heart did not correlate with the size of the defect. Small right-to-left shunts which are clinically insignificant but detectable by contrast echocardiography are present, or can be provoked by the Va...
Electropharmacology of amiodarone therapy initiation. Time courses of onset of electrophysiologic and antiarrhythmic effects.
Authors: L BMitchell, D GWyse, A MGillis, H JDuff
Journal: Circulation (1989)

The time courses of onset of the electrophysiologic and antiarrhythmic effects of amiodarone were determined with serial electrophysiologic studies in 34 patients with inducible ventricular tachycardia. A standardized oral loading dosage was used for all patients (1,200 mg/day for 14 days; 800 mg/day for 7 days; and 400 mg/day thereafter). Eleven patients had the studies performed at baseline and after 2, 6, 10, and 20 weeks. Subsequently, 23 patients had studies at baseline and after 2 and 10 weeks. Changes in atrial, sinus, and atrioventricular nodal properties and in conduction intervals were maximal within 2 weeks (early effects). For example, atrioventricular nodal Wenckebach cycle length increased between baseline (369 +/- 80 msec) and 2 weeks (498 +/- 78 msec) (p less than 0.001) but did not change further after 10 weeks (500 +/- 89 msec). However, ventricular Class III effects required 10 weeks to become maximal (late effects). For example, the QT interval during atrial pacing increased between ba...
Contributions of intracellular and extracellular Ca2+ pools to activation of myosin phosphorylation and stress in swine carotid media.
Authors: P HRatz, R AMurphy
Journal: Circulation Research (1987)

Contractile agonists can mobilize Ca2+ from both intracellular and extracellular stores in smooth muscle. This study addresses the role of Ca2+ mobilization as it relates to the complex manner by which Ca2+ regulates the contractile system in smooth muscle. In swine carotid media, both histamine and phenylephrine produced initial rapid increases in myosin phosphorylation and stress. Stress was sustained for the duration of the stimulus while myosin phosphorylation slowly declined to steady-state levels. Removal of extracellular Ca2+ or elimination of cellular Ca2+ influx did not dramatically reduce the initial rapid increase in myosin phosphorylation produced by either agonist but reduced steady-state levels of myosin phosphorylation to basal values. Initial rapid increases in stress were seen, but stress was not maintained. Following depletion of Ca2+ from sarcoplasmic reticulum, muscle activation by Ca2+ influx in the presence of phenylephrine occurred without an initial transient in myosin phosphorylat...
Age-related cardiovascular effects of catecholamines in anesthetized piglets.
Authors: N MBuckley, P MGootman, E LYellin, PBrazeau
Journal: Circulation Research (1979)

We studied cardiac and peripheral circulatory effects of graded doses of catecholamines (0.05-1.0 microgram/kg) in piglets aged less than or equal to 1 day, 2--4 days, 1 wweek, 2 weeks, and 2.5-3 months, under anesthesia with pentobarbital. We evaluated cardiovascular function from simultaneous recordings of aortic pressure, ventricular pressure and its first derivative, heart rate, and phasic carotid and femoral blood flows. We calculated vascular resistance as the ratio of mean aortic pressure to mean flow. The age of onset of a given cardiovascular response was determined, and magnitudes of each type of response were compared among the age groups. Norepinephrine elevated the blood pressure at all doses in piglets of all ages, elicited reflex bradycardia only in older piglets, and increased carotid resistance. Epinephrine elevated the blood pressure at all doses in piglets less than 1 week old, but low doses lowered the blood pressure in piglets older than 1 week of age; resistance changes in the femora...
Prospective Evaluation of a New Artificial Intelligence System For Detection of Colon Polyps
Authors: C Zippelius, J Schedel, D Brookman-Amissah, K Muehlenberg, W Schorr, A Salzberger, C Federle, F Zeman, O Pech
Journal: Endoscopy (2021)

Aims The adenoma detection rate (ADR) varies significantly between different endoscopists leading to an adenoma miss rate (AMR) of up to 26 %. To improve endoscopic quality and to reduce the rate of interval cancer artificial intelligence (AI) systems can be valuable. We evaluated the efficacy of an AI system in real time colonoscopy and its influence on the AMR and the ADR in a clinical setting.
Clinical and electrophysiologic characterization of automatic junctional tachycardia in adults.
Authors: M ARuder, J CDavis, MEldar, J AAbbott, J CGriffin, J JSeger, M MScheinman
Journal: Circulation (1986)

Junctional ectopic tachycardia has been described in infants but not in adults. Five adults with rapid symptomatic paroxysmal junctional tachycardia, distinct from the more common slower nonparoxysmal junctional tachycardia, were recently evaluated. The tachycardia was irregular (rate 120 to 250) and accompanied by periods of atrioventricular dissociation and narrow QRS complexes. A junctional origin was documented during electrophysiologic study in four of the five patients. Analysis of Holter recordings; the response to exercise, isoproterenol, and propranolol; and the effects of atrial and ventricular stimulation appeared to implicate abnormal automaticity of a high junctional focus that was catecholamine sensitive or dependent as the tachycardia mechanism. All patients responded somewhat to beta-blockers, although a combination of procainamide and propranolol proved to be the most effective therapy in one patient and another chose electrode catheter ablation of the atrioventricular junction rather tha...
Higher risk of allergies at 4–6 years of age after systemic antibiotics in the first week of life
Authors: Kim Kamphorst, Arine M. Vlieger, Berthe C. Oosterloo, Susan Waarlo, Ruurd M. van Elburg
Journal: Allergy (2021)

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