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The concentrations of HCB, PCB, and PAH in epiphytic mosses (Hylocomium splendens and Pleurozium schreberi) and forest humus were used to study the atmospheric exposure of conferous forests in a region in central Sweden. Air concentrations of HCB and PCB were monitored around an expected source. Moss contamination was used as a short-term exposure indicator, and humus contamination was assumed to indicate long-term exposure to HCB, PCB, and PAH.The level of HCB in mosses (0.4-1.7 ng/g, by dry weight, DW) complied well with background values. The levels of PCB measured as a sum of 7 identified PCB-congeners varied between 2-28 ng/g DW, with the highest levels in moss from the western part of the region, and decreasing concentrations from west to east. Around an expected PCB source in the southeastern part of the region the concentrations of PCB declined with increasing distance from the source area. The identified PAH concentrations in mosses varied between 39 and 730 ng/g DW. The PAH content in the mosses consisted mainly of nonvolatile PAH while the more volatile PAH were below the detection limit. The levels of HCB in humus were slightly more than in mosses (0.4-3.3 ng/g DW), and complied well with the background values. Sum PCB in the humus varied between 2 and 28 ng/g DW. The PAH in the humus were mainly nonvolatile PAH. The PAH concentrations in humus varied between 99 and 2600 ng/g DW. The air concentrations of PCB around the expected source (radius <1.5 km) were higher than background levels, and most likely caused the raised levels of PCB measured in the moss nearby.

Lund University was founded in 1666 as part of a strategy to assimilate the province of Scania in southern Sweden, which had been obtained from Denmark after a war ending in 1658. The present main building was erected in 1882. The University Hospital and the medical departments are located in the campus area northeast of the building. The main strength of the medical faculty lies in the neuro-biosciences. In retrospect, they offer a fascinating development with interesting historical connections as well as present-day contracts between many scientific disciplines. This shows once again that real scientific progress requires the interaction of many brains; in other words, the cross-fertilization offered by a critically large mass of scientists from different fields working relatively close together over long periods of time.

The distribution of cardiac output, as expressed by the regional uptake of thallium-201 following injection, has been studied by whole body scanning with a gamma-camera in six healthy persons and eight patients with aortic valvular disease. In the patients, cardiac output at rest and during exercise was also measured by the dye dilution technique. Combining the values of cardiac output and regional thallium uptake enabled the calculation of organ blood flow. The myocardial uptake of thallium at rest was 3.2 +/- 0.32% in the control group, which is significantly lower than 8.3 +/- 1.52%, found in the patients. The corresponding values measured in the kidneys were 12.5 +/- 1.91% in the healthy subjects and 7.1 +/- 0.50% in the patient material. Myocardial uptake increased and kidney uptake decreased in both groups following injection at peak exercise. Thallium uptake in the legs increased from about 13% at rest to about 39% at exercise in both groups. Distribution of thallium after injection at peak exercise did not, however, vary significantly between the two groups in the kidneys, abdominal area or the legs. Further methodological work is required before it can be ascertained to what extent the regional thallium uptake reflects the distribution of cardiac output. We nevertheless propose that the technique should be explored further, since it appears to be a simple non-invasive means of visualizing the distribution of the cardiac output in man under certain conditions.

The ability of thallium-201 scintigraphy to detect previous infarction (greater than 6 months ago) was studied in 43 patients with coronary artery disease, 39 with valvular heart disease, and 5 with cardiomyopathy or myocarditis. All patients had undergone selective coronary arteriography and left ventricular angiography. Thallium-201 scintigraphy at rest proved a very sensitive method for detecting previous infarction, also clinically silent. Scintigraphy was more sensitive than a recent ECG. However, scintigraphy can give falsely positive results.

1 The di-isobutyryl ester of terbutaline, ibuterol, was given subcutaneously and orally to healthy volunteers and its effects on heart rate, arterial blood pressure, and ECG were compared with those of terbutaline itself. The effects of the two substances were qualitatively identical, but quantitatively different. 2 By mouth, ibuterol acted more rapidly, and was 2-3 times more active. After intramuscular injection, ibuterol caused less increase in local blood flow than terbutaline. 3 Ibuterol can be regarded as a pro-drug, which in itself has little activity, but which can be made active in the body.

In regional hyperthermic perfusion with melphalan for patients with malignant melanoma of the leg, plasma leakage between the perfusion circuit and the systemic circulation was 4-7 ml X min-1. The melphalan concentration in the perfusate was biphasic, with half-lives of 8-12 mins for the initial phase and 19-28 mins for the second phase, after the first dose. After a second dose, the corresponding values were 11-13 and 26-34 mins. The highest concentration in general circulation was 0.38 micrograms X ml-1.

Fluorescein angiography (FA) of the foot soles was performed in 119 patients with arterial disease of the legs. Fluorescein was injected rapidly intravenously and sequential photographs were taken of the foot soles. Densitometric measurements were performed on three areas of each foot image: the big toe, the foot pad (just proximal to the little toe) and the heel. The relationships between different FA measurements and systolic arterial pressure in the ankle or the big toe were analysed. The appearance times of fluorescence correlated inversely with ankle pressure (P less than 0.001). The initial slopes of the fluorescence-time curves at all three sites of measurement correlated with ankle pressure (P less than 0.001). The initial slopes of fluorescence-time curves of the big toe and the foot pad correlated with toe pressure (P less than 0.001). In 12 patients effective arterial pressure was lowered by elevation of the feet, and in eight patients external pressure was applied to the foot by enclosing it in a box. The changes in FA evoked by these manoeuvres further strengthened the relationship between arterial pressures and FA measurements. We conclude that FA is a good method for evaluating circulation in the foot when neither ankle nor toe pressure is obtainable. In addition, FA may be useful when vascular disease is suspected in the presence of normal pressures, because the fluorescence distribution pattern was clearly abnormal in 11 of 16 such feet.

The carboxyhemoglobin (COHb) level was estimated in patients attending an anti-smoking clinic. A surprisingly large fraction of patients that reported "no smoking" were found to have abnormally high COHb. We believe that this discrepancy is due to the patients not reporting their smoking habits correctly. This phenomenon is further evidence that smoking should be regarded as a form of drug addiction in some persons. Some early relapses in stop-smoking programs can apparently be explained by the patient's admitting previously concealed smoking. For scientific purposes the results of stop-smoking cures should be evaluated by other means than the patient's own reports.

There is a multitude of method for assessing the efficiency of the arterial circulation in the legs. Most of these methods can give conclusive information about the patency of the main arteries in the leg; the level of an arterial obstruction can also be estimated. However, none of these methods provides a direct estimate of the functional importance of arterial lesions of light to moderate severity. The present report describes preliminary findings of the distribution of intravenously injected 201Thallium, a potassium analogue, in the legs during exercise provoking symptoms of ischemia. From this pilot study the general impression is that the thallium uptake pattern corresponds well with the clinical, physiologic, and angiographic picture.

Myocardial scintigraphy with cesium-131 and thallium-201 was performed in 191 patients. Previous myocardial infarctions localized to the anterior and lateral wall of the left ventricle were correctly diagnosed with both radionuclides. Inferior and posterior infarctions were only detected when thallium was used. In patients with non-informative ECG changes like bundle branch block, non-specific ST-T changes or with atypical symptoms, myocardial imaging made an essential contribution to the establishment of a correct diagnosis. The potential value of myocardial imaging in patients with valvular heart disease and in cardiomyopathy is described.

Pulsatile changes in the volume of an arm segment were recorded with an air-filled plethysmograph and related to intra-arterial blood pressure. Alterations in transmural arterial pressure were obtained by changing the pressure in a large chamber surrounding the entire arm. Arterial compliance values were calculated in late diastole when pressure and volume changes were slow. Compliance varied with transmural arterial pressure in a hyperbolic manner, rising steeply at low pressure. Noradrenaline and hypertensin did not change the arterial compliance values, while dihydroergotamine reduced them. Nitroglycerine caused a pronounced increase in compliance values in doses that did not change cardiac output and arterial pressure.

We studied the effect of the dihydropyridine calcium antagonists felodipine nimodipine on perfusion of the cerebral cortex in the spontaneously hypertensive rat (SHR). Nimodipine and felodipine were infused in equipotent doses in chloralose-anaesthetized SHR. During the infusion of a low and an intermediate dose of felodipine, mean arterial blood pressure was lowered to 90.5 +/- 1.5 and 67.1 +/- 2.9% of the control level. The nimodipine infusion lowered mean arterial pressure to 85.7 +/- 2.0 and 59.7 +/- 2.4% of the control level. At these pressures, cortical perfusion as measured by a laser Doppler flow technique increased to 123.5 +/- 6.9 and 130 +/- 5.4% of the control level during the felodipine infusion and to 114.0 +/- 1.6 and 122.3 +/- 3.2% of the control level during the nimodipine infusion. When these results were compared by covariance analysis of variance, felodipine induced a significantly greater change in cortical perfusion. At the highest dose of felodipine and nimodipine there was no significant difference in cortical perfusion between the two drugs. The administration of felodipine induced a decrease in cerebrovascular autoregulation. However, this impairment of cerebrovascular autoregulation is not likely to trigger cerebral hypoperfusion. Thus, for a mean arterial pressure of 55 mmHg, the laser Doppler-measured cortical flow was, if anything, elevated after felodipine administration.

Thermography, clinical examination and 99Tcm-plasmin test were performed in 112 patients and compared with phlebography. The study population consists of consecutive outpatients with symptoms compatible with deep venous thrombosis, who presented during regular clinic hours. Scoring systems were constructed for the clinical and thermographic evaluation. Both thermography and clinical diagnosis were insufficiently sensitive and specific for screening purposes. Plasmin test had a high sensitivity, 95%, but a low specificity. It is possible that a combination of thermography and clinical diagnostic criteria can provide an acceptable screening procedure. Combining thermography with a routine examination by the physician on duty yielded less favourable results.

Great investments have been made in computerized ECG interpretation but little attention has been paid to rationalization of such costly activities as recording, labelling and mounting ECGs, and still less to the presentation of ECGs. A system for such tasks is described. It includes a PDP8/E computer and modified ink jet ECG recorders, which write alphanumeric text and function as analogue input- and output-devices for the computer. On-line computer service is given independently to two laboratories for ECG at rest, VCG or exercise ECG. After averaging the ECG signal, the computer writes out a properly labelled ECG in an easily surveyable form. The visual interpretation of the ECG is entered and is then written on a new sheet together with the averaged 12-lead ECG and a rhythm strip. In exercise testing, the computer records and processes the ECG at predetermined intervals. The processing includes an automatic ST classification. A summarized presentationof the ECG before, during and after exercise allows easy visual identification of ECG changes. Experience of the system has mainly been obtained from 2 years of routine exercise ECG recording and to a limited extent from ECG and VCG recording at rest.

The effects on heart rate and blood pressure during standing, and on plethysmographic arterial pulsation in the calf, of nitroglycerin 0.5 mg sublingually, 6.5 mg orally and a placebo tablet were studied for up to 8 h. Sublingual nitroglycerin increased heart rate and arterial pulsation; the peak height and duration of these effects occurred at slightly different times. Oral nitroglycerin had no effect on heart rate but did increase pulsations as compared to placebo. In the orthostatic test, heart rate and pulse amplitude were affected by both forms of administration. Comparing the areas-under-curve for these variables for the two forms suggested that, in comparison with sublingual nitroglycerin, about 1/3 of the oral nitroglycerin was biologically effective over 8 h. Pulse plethysmography appeared to be the most sensitive method for "bioassay" of nitroglycerin.

A female patient with a side-to-side fistula between the radial artery and the cephalic vein complained of pain in the three radial fingers during dialyses. Using 133-Xenon and histamine injected locally into the thumb musculature, local effective arterial pressure was found to be decreased, and to rise after compression of the fistula, or the radial artery distal to the fistula. The patient's symptoms thus were probably ischaemic and disappeared after ligation of the radial artery distal to the fistula. Ten more patients, of whom 9 had no local symptoms, were studied using the same technique. In 3, systolic blood pressure was measured in the thumb by a strain gauge technique. Some "steal" of thumb blood pressure by the fistula could be demonstrated in all patients but one and retrograde flow of blood in the artery distal to the fistula in 8. "Supernormal" Xenon wash-out occured when the pressure head was restored to normal by compression of the fistula or the radial artery distal to it. This is probably due to a compensatory increase of the distal vascular bed. The technique can be used for investigation of patients with suspected ischaemia distal to an arteriovenous fistula, and to indicate the appropriate treatment, usually ligation of the artery distal to the fistula.

A new, non-ionic low osmolar contrast medium, iohexol 240 mg I/ml, has been tested in a randomized double blind parallel investigation versus meglumine-Ca metrizoate 200 mg I/ml. The study was performed to evaluate the suitability of the contrast medium in phlebography. No post-phlebographic complications were seen in the 24 patients examined with iohexol 240 mg I/ml or in 8 patients examined with iohexol 300 mg I/ml. In the 19 patients examined with metrizoate 200 mg I/ml, 7 had a post-phlebographic thrombotic complication (37%). The radiographic image quality was not significantly different between the two contrast media, neither were the immediate side effects during contrast injections. It has thus been shown that iohexol is a suitable contrast medium in phlebography of the lower limb and that it is preferable to conventional contrast media.

The primary effect of nitrates on the circulatory system is a relaxation of capacitance vessels on the venous and arterial side, while dilatation of resistance vessels (arterioles) is a secondary phenomenon, or occurs only at higher doses. Relaxation of arteries may augment flow in conditions where these vessels offer an increased resistance due to e.g. spasm. Relaxation of capacitance arteries explains in part the lower systolic blood pressure after nitroglycerin. Improved "Windkessel" function may augment diastolic arterial pressure and thus improve coronary perfusion. Some methods for measuring arterial compliance are described. It is suggested that more simple measurements of arterial pulsations may be used for studying nitroglycerin tolerance.