bluuebunny/crossref_metadata_2025_split huggingface dataset:
Atrial natriuretic peptide during acute treatment of congestive heart failure
Authors: Berglund H. , Bevegård S. , Carlens P. , Hedner J. , Hedner T. 
Published: April 2008

Summary. Atrial natriuretic peptide (ANP) induces potent diuretic/natriuretic, vasorelaxing and aldosterone inhibitory effects. Increased plasma levels in congestive heart failure (CHF) have been reported. The aim of this study was to investigate plasma immunoreactive ANP (ir‐ANP) levels during acute treatment of CHF. Seven patients with CHF underwent cardiac catheterization. Ir‐ANP plasma levels were followed up to two h after administration of an orally given phosphodiesterase inhibitor (Milrinone); a substance with positive inotropic and peripheral vasodilating properties. In all patients cardiac output increased and cardiac filling pressures decreased markedly. Initially high ir‐ANP plasma levels decreased. Our patients did not have an increased blood volume.It is concluded that plasma ir‐ANP levels in the pulmonary artery rapidly decrease when atrial pressure is reduced. These data suggest that atrial pressure is the major determinant for release of ir‐ANP in man and that the ability to respond quickly to changes in cardiac filling pressures is maintained in patients with severe CHF. Plasma ir‐ANP levels may also become useful as an index of the degree of heart failure and serve as a tool in monitoring response to drug therapy.
Spirometry in healthy adult never‐smokers
Authors: Oxhøj H. , Jeppesen G. Mostgaard , Larsen V. Højkjær , Jørgensen B. 
Published: April 2008

Summary. Spirometry was performed in 277 female and 240 male subjects constituting a random, unbiased population sample representative for the population of Denmark. Equipment, calibration and measurement procedures conformed strictly with established standards.Statistical analysis showed that certain power transformations (cubic, quadratic or square root) of the data produced models that fitted the data statistically significantly better than linear models, where no transformations are applied, or logarithmic models where a logarithmic transformation is applied to the response variable. Differences between predictions obtained with the three models were, however, small and without practical significance.Neither rigid adherence to established, well documented standards nor elaborate statistical analysis reduced the inter‐individual variance significantly in comparison to previous investigations.The results emphasize that it is important that reference values are appropriate for the methods and population in question.
Influence of vibration on endurance of maximal isometric contraction
Authors: Samuelson B. , Jorfeldt L. , Ahlborg B. 
Published: April 2008

Summary. In order to investigate how vibration affects endurance during muscular contraction, knee‐joint extension efforts were performed with and without superimposed vibrations. Fourteen healthy non‐smoking 20‐year‐old males performed maximal isometric and sustained knee‐joint extension efforts (angle 90°) in sitting posture three times with each leg, with or without vibration. The tests were done once with each leg in a randomly chosen order. The frequency of the vibration was 20 Hz and the acceleration 20 m/s2 RMS, applied in a horizontal sagittal direction to the ankle. The endurance was defined as the time in seconds that it took for the exerted force to decrease by 10% of the initial value.The endurance time averages 22.5 s without vibration and 15.8 s with vibration. The vibratory stress reduced endurance by 6.7±1.84 s (mean ±SEM) (P<0.005). The difference in maximal force recorded initially was 34 ± 1.9 N (P<0.1). Our conclusion is that vibration may decrease the endurance of maximal och sustained isometric muscular contraction.
Pulmonary vascular resistance rises with lung volume on exercise in obstructed airflow disease
Authors: Schrijen F. V. , Henriquez A. , Carton D. , Delorme N. , Butler J. 
Published: April 2008

Summary. There has been experimental evidence that lung distension produces an increase in pulmonary vascular resistance (PVR). To study this effect in patients, we measured functional residual capacity (FRC) by helium dilution at rest and during lowload supine exercise in 30 patients with chronic obstructive pulmonary disease. Pulmonary haemodynamics were studied in these patients under the same conditions.FRC increased from rest (4·32 ± 0·21 1) to exercise (4·71 ± 0·20, P<0·001) but the change was smaller in the patients with the highest FRC at rest: there was a significant negative correlation between FRC change and FRC at rest (r=–0·38, P<0·01). There were seven patients with a small FRC change (<0·2 1) with exercise and 10 patients with a marked increase (>0.5 1). Exercise was of the same load on average. FRC at rest was 5·1 1 in the first group and 4 1 in the second (P<0·05). Blood gases were almost identical at rest, and almost unchanged during exercise. PVR decreased from rest to exercise by 33 dyn.s.cm‐5 in the first group and increased by 24 in the second (P<0·01). There was a significant correlation (P<0·05) between PVR and FRC changes from rest to exercise. These results suggest that lung distension may play a role in the PVR increase seen in some COPD patients with exercise.
Nitrogen dead space in heavy smokers aged 44–58 years
Authors: Rosberg H. E. , Wiberg R. , Arborelius M. 
Published: April 2008

Summary. Functional and alveolar dead spaces for nitrogen (Vdf and Vdalv) were calculated in a population of 20 male and 20 female heavy smokers and compared to data from static and forced spirometry (functional residual capacity [FRC], residual volume [RV], lung clearance index [LCI] and volume of trapped gas [VTG]) obtained with the same multiple‐breath nitrogen wash‐out as the dead spaces, and to variables considered sensitive to small airways disease measured with a single‐breath nitrogen elimination (closing volume in per cent of vital capacity [CV%], closing capacity in per cent of total lung capacity [CC%] and slope index [SI]).Both nitrogen dead spaces increased with tidal volume in smokers as well as in healthy non‐smokers. The majority of smokers were outside the predicted mean+2 SD for VTG (75%), CC and VDalv (70%) and SI (65%). The following variables were less sensitive for disclosing abnormality: CV (55%), RV (53%), LCI (38%) and forced expired volume in the first second (FEV1, 33%). If high sensitivity is considered preferable in epidemiological studies, the nitrogen dead spaces are equally as sensitive as the better of earlier described tests, and significantly superior to LCI and FEV1. Being tests that measure alveolar distribution of inhaled gas, they are probably sensitive to small airways disease.
Cardiovascular and metabolic response to adrenaline infusion in weight‐losing patients with and without cancer
Authors: Drott C. , Persson H. , Lundholm K. 
Published: April 2008

Summary. Fasting is generally accompanied by a decrease in energy metabolism and hormones. On the other hand, indirect evidence has suggested that the response to adrenergic agonists may be maintained or even increased in malnutrition. The present study evaluated whether weight‐losing patients with and without cancer have increased plasma concentrations of catecholamines and different responses to intravenously infused adrenaline compared to weight‐stable individuals. Eight malnourished cancer and 10 non‐cancer patients (11% weight loss) were compared to seven well‐nourished and weight‐stable patients. Adrenaline was infused i.v. at a rate of 0·005 μg min‐1 kg‐1 body weight during 40 min followed by a 40 min rest period (without infusion) and then a final 40 min period with i.v. adrenaline infusion (0·02 μg min‐1 kg‐1 body weight).Plasma glycerol concentration at fast was higher in weight‐losing patients compared to weight‐stable individuals. Whole body oxygen uptake, carbon dioxide production, heart rate and plasma concentrations of free fatty acids (FFA) increased while the mean arterial pressure decreased significantly in response to adrenaline infusion at 0·02 μg kg‐1 min‐1 in both weight‐losing and weight‐stable patients. Adrenaline at 0·005 μg kg‐1 min‐1 increased plasma FFA levels by 19% (P<0·05) in weight‐losing patients while no significant alteration was observed in well‐nourished patients. Adrenaline infusion at 0·02 μg kg‐1 min‐1 decreased the mean arterial blood pressure and stimulated respiratory gas exchange and heart rate significantly more in weight‐losing than in weight‐stable patients. The slopes for oxygen uptake, carbon dioxide production, heart rate, plasma FFA and plasma glycerol vs. plasma adrenaline and noradrenaline were all significantly steeper (P<0·05–0·01) in malnourished patients than in well‐nourished controls.The present study suggests an increased sensitivity to adrenaline in weight‐losing patients compared to matched controls with normal nutritional state and stable weight.
Plasma lipid and lipoprotein profiles in pre‐ and post‐menopausal middle‐aged runners
Authors: Higuchi M. , Iwaoka K. , Ishii K. , Matsuo S. , Kobayashi S. , Tamai T. , Takai H. , Nakai T. 
Published: April 2008

Summary. Plasma lipid and lipoprotein profiles were compared in middle‐aged trained and untrained women before and after menopause. Subjects were assigned to one of four groups:(1) pre‐menopausal trained (Pre‐T: n= 17, aged 42 ±5 years, body fat 19±5%, training distance 53 ±20 km week‐1, V̇o2max 49 ±4 ml kg‐1 min‐1, mean±SD);(2) pre‐menopausal untrained (Pre‐UT: n= 26, 42 ±5 years, 24 ±7%, 34 ±6 ml kg‐1 min‐1);(3) post‐menopausal trained (Post‐T: n= 16, 54 ±3 years, 20 ±4%, 43 ±19 km week‐1, 41 ±5 ml kg‐1 min‐1); and(4) post‐menopausal untrained (Post‐UT: n= 15, 55 ±3 years, 25 ±6%, 31 ±3 ml kg‐1 min‐1).There were no significant differences in total cholesterol (range 173–194 mg dl‐1), triglyceride (56–72 mg dl‐1), and HDL‐cholesterol (HDLC: 76–85 mg dl‐1) among the four groups. LDL‐cholesterol (LDLC) in the post‐menopausal women (Post‐T: 96 ±32 mg dl‐1; Post‐UT: 104 ±23 mg dl‐1) tended to be higher than in the premenopausal women (Pre‐T: 86 ± 25 mg dl‐1, Pre‐UT: 81 ± 23 mg dl‐1). LDLC/HDLC ratio in Post‐UT (1·42 ±0·38 unit) was higher than in the pre‐menopausal women (Pre‐T: 1·03±0·31 unit, P<0·01; Pre‐UT: 1·10±0·38 unit, P<0·05), whereas the ratio in Post‐T (1·20 ±0·38 unit) was not different from those of the pre‐menopausal groups. These results suggest that endurance running protects against the increase in LDLC/HDLC ratio that frequently occurs after menopause.
Clinical physiology: an accepted branch of physiology
Authors: Linderholm H. 
Published: April 2008

Summary. Clinical physiology is a branch of physiology particularly dealing with functional disturbances in disease (pathophysiology) and the integrated function of the human body in disease against the background of normal function in healthy subjects, suitable physiological methods for the study of patients — particularly for diagnostic purposes — as well as for research, and the education of medical students and laboratory assistants in these fields. Departments of clinical physiology in university hospitals form a bridge between basic physiology and many clinical specialities.Independent departments of clinical physiology developed early in Sweden due to the work of Professor Torgny Sjöstrand at the Karolinska Hospital in Stockholm, and have been models of research, teaching and hospital organization which have been followed in several other countries.The International Union of Physiological Sciences (IUPS) has recognized clinical physiology as a separate branch of physiology by approving a Commission of Clinical Physiology which has contributed to the programme of this and, we hope, future congresses, as well as promote the development of clinical physiology internationally.
Pulmonary absorption of instilled and inhaled DTPA in smokers
Authors: Groth S. , Kristjansen P. E. G. , Mortensen J. , Merrild D. 
Published: April 2008

Summary. Pulmonary absorption of DTPA (diamine‐triethylene‐penta‐acetic acid) has been widely adopted as an index of pulmonary epithelial permeability. The aim of this study was to analyse:

if measurements of pulmonary absorption are influenced by the amount of fluid being administered to the lungs together with the DTPA; and
if all DTPA administered to the lungs is equally accessible for pulmonary absorption.

To this end DTPA was instilled into a lung segment of six smokers in association with a bronchoscopy. In six other subjects (five smokers and one ex‐smoker) the DTPA was inhaled as an aerosol. Pulmonary absorption of DTPA was calculated from the plasma DTPA content, as determined for 4–10 h after the administration of the DTPA. We found that the mean transit time for the absorption of instilled DTPA, i(L), across the pulmonary membranes was significantly (P<0·05) longer (median 1498 min, range 955–2636 min) than the fi(L) of the absorption of the inhaled DTPA (median 131 min, range 44–512 min). Pulmonary clearance of the inhaled aerosolized DTPA tended to be faster when determined by external detection for 4 h, than when estimated from plasma samples, suggesting that not all pulmonary DTPA may be equally accessible for absorption from the pulmonary lining fluids. We conclude that pulmonary absorption of DTPA is influenced by the volume of fluid being administered to the lungs in association with the measurements. Not all pulmonary DTPA, however, is equally accessible for absorption, rendering external detection of pulmonary clearance of DTPA sensitive to a variety of factors other than pulmonary absorption.
Prognosis and diagnostic work‐up in patients admitted for, but without, myocardial infarction — the value of nuclear medicine examinations
Authors: Launbjerg J. , Fruergaard P. , Jørgensen F. B. , Madsen J. Kyst , Hesse B. 
Published: April 2008

Summary. Patients admitted for acute myocardial infarction that is not confirmed (non‐AMI) have a prognosis only slightly better than that of patients with confirmed infarction. In a prospective, prognostic study of 158 patients with non‐AMI the combination of exercise ECG and transient defects demonstrated at 201thallium scintigraphy identified low‐ and high‐risk groups better than either examination alone.The purpose of a new, still ongoing study of non‐AMI patients is to establish a relevant, cost‐effective examination programme in order to arrive at a positive diagnosis in each non‐AMI patient. Preliminary results of lung perfusion/ventilation scintigraphy suggest a rather low frequency of pulmonary embolism. Preliminary data of oesophageal scintigraphy suggest that about 25% of the non‐AMI patients have abnormal mean transit times. The clinical significance of these data are discussed.
Pulmonary clearance of inhaled [99Tcm]DTPA: effects of ventilation pattern
Authors: Evander E. , Wollmer P. , Jonson B. 
Published: April 2008

Summary. While a rise in lung volume is known to increase the pulmonary clearance of technetium‐99m‐labelled dietylene triamine pentaacetate ([99Tcm]DTPA), little interest has been focused on the effects of changes in ventilation frequency, tidal volume and airway pressure. We studied adult, anaesthetized and intubated rabbits during three ventilation patterns (VP) using pressure controlled ventilation (Servo Ventilator 900C). VP was either deep slow (f=20 min‐1, tidal volume (VT) = 30 ± 4 ml kg‐1 and positive end‐expiratory pressure (PEEP) = 0·2 kPa [VP 20/ 0·2, n= 8]) or rapid shallow (f=80 min‐1, VT= 11 ±2 ml kg‐1 and PEEP = 0·2 or 0·4 kPa [VP 80/0·2, n= 6 and VP 80/0·4, n= 6]). The mean airway pressure was similar at VP 20/0·2 and VP 80/0·4. During administration of [99Tcm]DTPA aerosol all animals were ventilated under the same conditions (f=40 min‐1 and PEEP = 0·2 kPa). The pulmonary clearance rate expressed as the half‐life time (T1/2) of [99Tcm]DTPA was at VP 80/0·2 = 113 ± 31 min, at VP 80/0·4 = 70 ± 24 min (P < 0·01 compared to VP 80/0·2) and at VP 20/0·2 = 36± 18 min (P <0·001 compared to VP 80/0·2 and P <0·01 compared to VP 80/0·4).We conclude that the pulmonary clearance of [99Tcm]DTPA increases

during rapid shallow ventilation when PEEP is increased from 0·2 to 0·4 kPa;
during deep slow ventilation relative to rapid shallow ventilation even when the mean airway pressure is similar.
Combined left and right ventricular volume determination by radionuclide angiocardiography using double bolus and equilibrium technique
Authors: Stokholm K. H. , Stubgaard M. , Møgelvang J. , Henriksen O. 
Published: April 2008

Summary. Eighteen patients with ischaemic heart disease were studied. Left and right ventricular volumes including cardiac output (forward flow) were determined by radionuclide angiocardiography using a double bolus and equilibrium technique. As reference, cardiac output was simultaneously measured by indicator dilution. The radionuclide technique comprised four steps:

a first‐pass study of right ventricle;
a bolus study of left ventricle;
an equilibrium study of left ventricle;
determination of the distribution volume of red blood cells.

Absolute volumes of left ventricle were determined from steps 2+3+4. Absolute volumes of right ventricle were calculated from stroke volume and right ventricular ejection fraction (EF) which in turn was determined from step 1 by creating composite systolic and composite diastolic images. There was an acceptable agreement between stroke volume determinations by radionuclide angiocardiography and indicator dilution (r= 0.74; P<0.001). Stroke volume determination by radionuclide was 83±20 ml (mean±SD) and by indicator dilution 84±20 ml with a difference of ‐1±15 ml (NS). Cardiac output determination by radionuclide was 5.24±1.37 1 min‐1 and by indicator dilution 5.28±1.23 1 min‐1 with a difference of ‐0.04±0.95 1 min‐1 (NS). Left ventricular EF was 0.44 ±0.14 and right ventricular EF 0.57 ±0.10. The intra‐observer coefficient of variation for duplicate calculations of the radionuclide determinations was 5.5% for stroke volume, 2.5% for left ventricular EF and 4–8% for right ventricular EF.
Reflex actions of knee joint afferents during contraction of the human quadriceps
Authors: Iles J. F. , Stokes M. , Young A. 
Published: April 2008

Summary.

The spinal reflex actions of afferents stimulated by knee joint distension have been investigated in man.
Cannulation of the knee and infusion of saline raised intra‐articular pressure, especially during quadriceps contraction. High pressures did not induce any sensation of pain. Pressure was taken as an index of joint proprioceptor activation.
Increased pressure progressively depressed the quadriceps H‐reflex, both at rest and during quadriceps contraction. There was no indication of a threshold pressure for this inhibitory action.
It is concluded that joint distension inhibits quadriceps motoneurons through spinal pathways that still operate during voluntary contraction. These pathways could thus contribute to pathological weakness after joint injury.
Joint distension produced spatial facilitation of non‐reciprocal inhibition of quadriceps H‐reflexes from afferents in the tibia1 nerve.
Initial circulatory responses to changes in posture: influence of the angle and speed of tilt
Authors: Sprangers R. L. H. , Veerman D. P. , Karemaker J. M. , Wieling W. 
Published: April 2008

Summary. To assess if changes in the angle or speed of tilt could account for the differences between the initial (first 30 s) circulatory responses induced by active and passive changes in posture, as found in previous studies, we investigated the initial heart rate and blood pressure responses induced by stand up from supine and various head‐up tilt manoeuvres in 12 healthy, male subjects. Comparison was made between 70° head‐up tilt in 3 s, 90° head‐up tilt also in 3 s and 70° head‐up tilt in 1·5 s, using an automatic pneumatic‐driven tilt table with foot support.It was found that the initial heart rate and blood pressure responses induced by the three tilt manoeuvres were almost identical in time course and amplitude, but significantly different from those induced by stand up.The results of this study prove that regardless of the angle and speed of tilt, the initial circulatory responses induced by passive changes in posture are essentially different from the responses induced by active changes in posture.
Circulatory responses to stand up: discrimination between the effects of respiration, orthostasis and exercise
Authors: Sprangers R. L. H. , van Lieshout J. J. , Karemaker J. M. , Wesseling K. H. , Wieling W. 
Published: April 2008

Summary. The initial circulatory responses to an active change in posture (stand up from supine) were compared with the responses induced by a passive change in posture (head‐up tilt) and a burst of muscular exercise on a bicycle ergometer (upright cycling) in order to differentiate between exercise‐ and orthostasis‐induced effects. In eight subjects heart rate responses and in four subjects intra‐arterial pressure transients were measured. In addition the effects of respiration on heart rate responses to the three manoeuvres were assessed.Both stand up and cycling induced almost superimposable and pronounced heart rate responses lasting for about 30 s. This contrasts with the more gradual increases following head‐up tilt. Changing the respiratory phase during the performance of the manoeuvres exerted its effect on heart rate responses in the first 5 s only.Like stand up, cycling induced a transient blood pressure fall lasting for 30 s on average. As both manoeuvres were performed during inspiration the transients observed are not caused by involuntary Valsalva straining.In conclusion, the maximum and duration of the heart rate responses induced by stand up, cycling and head‐up tilt are not influenced by respiratory activity.The initial fall in blood pressure following stand up is probably the result of the muscular effort of the manoeuvre and not due to the effects of orthostasis or Valsalva straining.
Left and right ventricular diastolic function during acute pericardial tamponade
Authors: Smiseth O. A. , Frais M. A. , Junemann M. , Kingma I. , Refsum H. , Smith E. R. , Lipton M. J. , Tyberg J. V. 
Published: April 2008

Summary. The aim of the study was to determine the effect of acute pericardial tamponade on left (LV) and right ventricular (RV) intracavitary and transmural pressure‐volume (P–V) relations and to assess the effect of changing blood volume during tamponade on LV and RV volumes. The experiments were done in 11 acutely instrumented anaesthetized dogs in which LV and RV volumes were determined by computed tomography (CT) (n= 5) and LV and RV diameters by sonomicrometry (n= 6). Pressures were measured in the pericardium (balloon transducer), in the aorta and in the ventricles. Incremental pericardial infusion (up to 180 ml) caused a progressive left and upward shift of the LV and the RV intracavitary P–V relationship. This shift was entirely due to increased pericardial prressure (PP). The induction of tamponade caused no change in the LV and RV transmural P–V relationship. During tamponade with ventricular filling pressures above 10–15 mmHg, blood volume expansion caused only minimal increase in LV and RV volumes.In conclusion, pericardial tamponade shifted the LV and the RV intracavitary diastolic P–V relation by increasing PP. However, there was no change in the transmural P–V relationship, indicating unchanged myocardial compliance. Volume loading caused only minimal increase in LV and RV volumes during tamponade.