Changes in the concentrations of phenolics and photosynthates in Scots pine (Pinus sylvestris L.) seedlings exposed to nickel and copper.

Studies were done on the effects of elevated soil concentrations of copper (Cu) and (Ni) on foliar carbohydrates and phenolics in Scots pine (Pinus sylvestris L.). Four year-old seedlings were planted in pots filled with metal-treated mineral forest soil in early June. The experimental design included all combinations of four levels of Cu (0, 25, 40 and 50 mg kg(-1) soil dw) and Ni (0, 5, 15 and 25 mg kg(-1) soil dw). Current year needles were sampled for soluble sugar, starch and phenolics at the end of September. Ni increased sucrose concentration in the needles, indicating disturbances in carbohydrate metabolism. Trees exposed to Ni had higher concentrations of condensed tannins compared with controls. In contrast, concentrations of several other phenolic compounds decreased when seedlings were exposed to high levels of Cu or to a combination of Ni and Cu. The results suggest that concentrations of phenolics in Scots pine needles vary in their responses to Ni and Cu in the forest soil.

Quality of dynamic radionuclide renal imaging: multicentre evaluation using a functional renal phantom.

The aim of this study was to evaluate the quality of dynamic radionuclide renal imaging in Finland. Nineteen nuclear medicine departments participated. A functional renal phantom was imaged and interpreted as a patient-like study. Reconstruction and printouts were performed according to the clinical routine of each laboratory. Three nuclear medicine specialists anonymously evaluated the quality of the image sets. The visual scores of the experts were ranked from one to five. In addition, several numerical time-activity parameters were calculated and compared between the laboratories. The average visual scores of the experts for the image sets were 3.2+/-0.5 (range 2.4-4.2). Only two laboratories received a score value of 4 or higher. The average error for the time to reach maximum activity (T(max)) ranged from -29 to +18% and for the washout time to reach half activity from maximum activity (T(1/2)) ranged from -43 to +66%. These results suggest that the difference in calculated parameters between laboratories is most probably due to variations in study protocols and analysis programmes. The need for external quality assurance and quality improvement in nuclear renal imaging is evident and is recommended for regular use.

Stress indications in copper- and nickel-exposed Scots pine seedlings.

Scots pine nursery seedlings were planted in pots, five seedlings per treatment, and placed in an experimental field at the University of Oulu in northern Finland at the beginning of June 1997. Copper and nickel sulphates were mixed with forest mineral soil before seedling planting. The metal levels ranged from 0 to 25 mg Ni kg(-1) dry soil and 0 to 50 mg Cu kg(-1) in dry soil and in combinations of both metals. Current year's needles for element analyses, EDS microanalyses, microscopy and glutathione and peroxidase activity analyses were collected from 1-5 seedlings per treatment in September. Seedling biomass in controls, Cu25 and Cu50 differed significantly from the Ni25Cu50 treatment. The root/shoot ratio was highest in the Ni5 treatment, indicating good root growth, though the roots were visibly healthier in the Cu25 treatment than in the Ni5 treatment. At higher Ni levels, the condition of roots deteriorated. The proportion of plasmolysed mesophyll cells was highest in the Ni25 treatment. Copper-treated seedlings did not suffer from Cu stress, because no severe injuries were seen in either the roots or the needles in Cu-exposed seedlings. The needle concentrations of Cu increased only slightly due to treatments. Ni accumulation in needles increased with increasing concentrations in soil. Needles of Cu-treated seedlings had less oxidized glutathione than those of Ni-treated seedlings, but the roots had higher, not significantly, peroxidase activity levels. Light-colored, swollen thylakoids were occasionally observed in the Ni25Cu50 treatment, indicating some interaction between Ni and Cu. Ni seemed to cause more oxidative stress to the seedlings than copper, which was manifested as a decreased GSH level and an increased proportion of GSSG in the Ni treatments. Copper together with nickel strongly decreased root growth, the root/shoot ratio being lowest in the Ni25Cu50 treatment.

Quality of myocardial perfusion single-photon emission tomography imaging: multicentre evaluation with a cardiac phantom.

The aim of the study was to evaluate quality of myocardial perfusion single-photon emission tomography (SPET) imaging in Finnish hospitals. Nineteen nuclear medicine departments participated in the study. A myocardial phantom simulating clinical stress and rest conditions was filled with routinely used isotope solution (technetium-99m or thallium-201). The cardiac insert included three reversible defects (simulating ischaemia): 30x30x14 mm(3) septal (90% recovery at rest), 30x20x14 mm(3) posterobasal (full recovery) and 20x20x14 mm(3) lateral (full recovery). There were two fixed defects (simulating infarct): 30x20x14 mm(3) postero-apical and 10x10x6 mm(3) apical. The phantom was imaged and interpreted as a myocardial perfusion patient. Reconstruction, printout and reporting were performed according to the clinical routine of each centre. Three nuclear medicine specialists anonymously evaluated the quality of the image sets. The visual scores of the experts were ranked from 1 to 5. Additionally, points from 0 to 8 were given to research reports according to how well perfusion defects were detected. Quantitative points were calculated by comparing background-subtracted and -normalized counts from 12 regions of interest between stress and rest images. Results for technetium studies (12 departments) were better than those for thallium (7 departments). The average visual scores of the experts were 3.7+/-0. 9 for all image sets, 3.2+/-0.5 for thallium users and 3.9+/-0.6 for technetium users (P=0.003). Five laboratories received a low score which, according to the specialists, is barely sufficient for limited clinical use. Average points for the reports were 5.6+/-2.1, 4.9+/-1.5 and 6.5+/-1.7 (P=0.051), and for the quantitation 8.2+/-1. 0, 7.9+/-0.4 and 8.4+/-1.1 (P=0.185), respectively. Seven out of 22 interpreters did not detect the lateral 20x20x14 mm(3) defect; five of them used thallium. This study demonstrated the heterogeneity of myocardial perfusion SPET in Finland. The participating laboratories used a wide scale of methods and, sometimes, inappropriate imaging protocols. The need for quality assurance in nuclear cardiology, correct use of SPET instrumentation and objective comparison of clinical studies is evident. The method described is suitable for external quality assurance and quality improvement of myocardial SPET imaging, and is recommended for regular use in nuclear medicine.

Quality of brain perfusion single-photon emission tomography images: multicentre evaluation using an anatomically accurate three-dimensional phantom.

The aim of the study was to evaluate the quality of routine brain perfusion single-photon emission tomography (SPET) images in Finnish nuclear medicine laboratories. Twelve laboratories participated in the study. A three-dimensional high resolution brain phantom (Data Spectrum's 3D Hoffman Brain Phantom) was filled with a well-mixed solution of technetium-99m (110 MBq), water and detergent. Acquisition, reconstruction and printing were performed according to the clinical routine in each centre. Three nuclear medicine specialists blindly evaluated all image sets. The results were ranked from 1 to 5 (poor quality-high quality). Also a SPET performance phantom (Nuclear Associates' PET/SPECT Performance Phantom PS 101) was filled with the same radioactivity concentration as the brain phantom. The parameters for the acquisition, the reconstruction and the printing were exactly the same as with the brain phantom. The number of detected "hot" (from 0 to 8) and "cold" lesions (from 0 to 7) was visually evaluated from hard copies. Resolution and contrast were quantified from digital images. Average score for brain phantom images was 2.7 +/- 0.8 (range 1.5-4.5). The average diameter of the "hot" cylinders detected was 16 mm (range 9.2-20.0 mm) and that of the "cold" cylinders detected, 11 mm (5.9-14.3 mm) according to visual evaluation. Quantification of digital images showed that the hard copy was one reason for low-quality images. The quality of the hard copies was good only in four laboratories and was amazingly low in the others when comparing it with the actual structure of the brain phantom. The described quantification method is suitable for optimizing resolution and contrast detectability of hard copies. This study revealed the urgent need for external quality assurance of clinical brain perfusion SPET images.

Assessing the critical level of SO2 for Scots pine in situ.

A field survey was performed in eastern Finland, where measured ambient SO2 concentrations were 1.4-3.8 microg m(-3) a(-1) and bulk S deposition 0.17-0.32 g m(-2) a(-1) in 1991-1993. The accumulation of sulphur (S) in needles of Scots pine (Pinus sylvestris L.) was studied with XRF, IC and FESEM analyses and the needle damage examined under a light microscope and by SEM. Foliar N concentrations were also measured. Foliar total S concentrations were observed to be above the normal S level (500-700 microg g(-1)) over almost the whole area. Slight chlorosis and/or necrosis of the needle tips and stomatal areas, changes in the needle surface waxes and localization of S into needle tips and mesophyll cells around the stomata suggested the impact of S deposition, as did the calculations of St/Nt, and 'predicted' and 'excess' S. A concentration of about 900 microg g(-1) may be considered a critical level for foliar St in areas with low N supply.

Abnormalities in left ventricular diastolic function in male patients with rheumatoid arthritis without clinically evident cardiovascular disease.

Epidemiological studies have suggested that patients with rheumatoid arthritis (RA) have increased mortality due to cardiovascular disease. We studied cardiac performance in 12 asymptomatic male patients with RA and 14 control subjects to elucidate early disturbances in cardiac function. In echocardiography, isovolumic relaxation time was longer (64 +/- 6 vs. 49 +/- 3 ms, mean +/- SEM, P = 0.010) and peak filling rate (134 +/- 10 vs. 159 +/- 6 mm s-1, P = 0.015) lower in patients with RA than in control subjects, reflecting an impairment in left ventricular diastolic function. Left ventricular systolic function assessed by radionuclide angiocardiography at rest and during exercise was similar in both groups. There were no differences between the patients with RA and control subjects in the heart rate, systolic blood pressure and oxygen uptake during peak exercise. Left ventricular diastolic function is impaired in spite of normal left ventricular systolic function in patients with RA without clinically evident cardiovascular disease and this may contribute to the excess of cardiovascular mortality in patients with RA.

Effect of hemodilution on maximal oxygen consumption, blood lactate response to exercise and cerebral blood flow in subjects with a high-affinity hemoglobin.

10 subjects with Hb Linköping (beta 36 Pro greater than Thr), a high-affinity hemoglobin variant, with a P50 of 2.2 kPa (16.5 mm Hg) were investigated before and 3-4 days after normovolemic hemodilution. Blood hemoglobin concentration decreased from 176 +/- 13 (SD) to 146 +/- 15 g l-1 and the red cell volume from 2.77 +/- 0.83 to 2.23 +/- 0.67 l. Maximal oxygen consumption decreased slightly by 2.7 +/- 3.8 ml min-1 kg-1 and maximal exercise power by 11 +/- 23 W; these changes were, however, not statistically significant. Maximal heart rate was unchanged (-1.1 +/- 6.4 beats min-1) while submaximal heart rate was consistently increased on comparable loads after hemodilution compared to before. The exercise ECG was normal both before and after hemodilution. Capillary lactate levels at exercise were always higher after hemodilution than before. Cerebral blood flow was normal both before and after hemodilution in all subjects but one who had a high flow. The grey matter blood flow increased slightly but significantly by 8.6 +/- 10.3 ml min-1 100 g-1 from before to after hemodilution. The results indicate that subjects with Hb Linköping have only limited benefit from their increased blood hemoglobin concentration.

Demonstration of disturbed free fatty acid metabolism of myocardium in patients with non-insulin-dependent diabetes mellitus as measured with iodine-123-heptadecanoic acid.

Myocardial free fatty acid metabolism and left ventricular function were evaluated in 15 middle-aged patients with non-insulin-dependent diabetes mellitus (NIDDM) and in 8 healthy control subjects. The study subjects had no evidence of coronary heart disease on the basis of clinical history, exercise ECG or myocardial perfusion scintigraphy. During peak exercise, iodine-123 hepatadecanoic acid (HDA) was intravenously injected. Myocardial activity distribution of 123I-HDA was measured 10, 30, and 50 min after exercise using single-photon emission tomography (SPET); and then further corrected by free 123I-iodine. Venous blood samples were drawn for detecting the plasma activity of 123I. The net extraction of 123I-HDA into the myocardium was obtained by dividing the corrected tissue 123I concentration by the integral of the plasma time activity curve. The net extraction was 0.40 +/- 0.06 min-1 (mean +/- SD) patients with NIDDM and 0.38 +/- 0.06 min-1 in control subjects (P greater than 0.1), respectively. The faster elimination rate of 123I-HDA was found in patients with NIDDM (0.029 +/- 0.008 min-1) than in control subjects (0.022 +/- 0.004 min-1; P less than 0.01). There was no statistically significant difference in left ventricular ejection fraction (LVEF) at rest between patients with NIDDM (53 +/- 9%) and control subjects (56 +/- 2%), whereas the increase of LVEF during exercise remained lower in patients with NIDDM (3.4 +/- 8.2%) than in control subjects (11.8 +/- 5.8%; P less than 0.025).(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical outcome and left ventricular function 23 years after acute coxsackie virus myopericarditis.

The clinical outcome of 18 patients, who presented with a Coxsackie virus myopericarditis in 1965, was evaluated 23 years later. Five patients had died, two of them had had heart failure. Thirteen patients and 23 healthy control subjects underwent exercise testing with gas exchange analysis. Left ventricular (LV) peak filling rate (PFR) was estimated by digitized M-mode echocardiography. Left ventricular ejection fraction was measured at rest and during exercise by radionuclide angiography. All patients were free of cardiac symptoms. Their clinical examination and the chest X-ray were normal. Peak oxygen consumption was not decreased in the patient group compared with the control group. PFR was significantly lower in the patient group than in the control group, 10.2 +/- 0.4 vs 13.2 +/- 0.4 cm s-1, P less than 0.001 (mean +/- SEM). LV ejection fraction was normal at rest in all patients (58 +/- 1%). An abnormal LV ejection fraction response to exercise was observed in two patients. Our data indicate that long-term prognosis after acute Coxsackie virus myopericarditis is good in a majority of patients.

Reversed left internal mammary artery graft for coronary bypass. Evaluation of function with digital subtraction angiography and radionuclide imaging.

Reversed left internal mammary artery grafting with retrograde flow to the left anterior descending coronary branch was used in five of 500 consecutive bypass operations. The indications were significant stenosis in the left subclavian artery (3 patients) or the proximal left internal mammary artery (1) and proximal damage to the left internal mammary artery during dissection from the thoracic wall (1). The postoperative clinical course was smooth in all five patients, with no evidence of myocardial ischemia. In follow-up averaging 14 months four patients were asymptomatic. The reversed internal mammary artery graft was visualized with digital subtraction angiography in four cases. Radionuclide imaging during exercise confirmed graft patency in all but the symptomatic patient, who was found to have an area of reversible ischemia anteriorly in the left ventricle.

Improvement of left ventricular function after starting insulin treatment in patients with non-insulin-dependent diabetes.

Left ventricular function was evaluated noninvasively before and three months after starting insulin treatment in nine patients (mean age 61.8 years, range 51-68 years) with non-insulin dependent diabetes showing an impaired insulin secretion capacity. After starting insulin treatment, fasting blood glucose decreased from 12.9 +/- 0.5 mmol/l (mean +/- SEM) to 9.8 +/- 1.2 mmol/l (p = 0.03), but the decrease of glycosylated haemoglobin Alc was not significant (9.0 +/- 0.4% vs. 8.3 +/- 0.6%). On systolic time intervals, PEP/LVET ratio improved from 0.44 +/- 0.03 to 0.37 +/- 0.02 (p = 0.03). On M-mode echocardiography, E-F slope became steeper (89 +/- 6 mm/sec vs. 103 +/- 8 mm/sec; p = 0.01) but no significant changes were observed in other variables reflecting diastolic or systolic function. On equilibrium radionuclide angiocardiography, the left ventricular ejection fraction at rest was similar before and after starting insulin treatment (48.6 +/- 3.2% vs. 49.2 +/- 2.8%) but during peak exercise the left ventricular ejection fraction improved significantly (51.0 +/- 5.3% vs. 59.9 +/- 4.7%; p = 0.02). The change of PEP/LVET ratio correlated significantly with the changes of blood glucose and glycosylated haemoglobin Alc levels, but the correlation between these metabolic variables and the change of left ventricular ejection fraction during exercise did not reach statistical significance. In conclusion, the left ventricular function improved concomitantly with improved metabolic control after starting insulin treatment in middle-aged patients with non-insulin-dependent diabetes having an impairment in insulin secretion capacity. This finding suggests that metabolic factors are involved in the left ventricular dysfunction observed in diabetes.

Anti-anginal efficacy of a controlled-release formulation of isosorbide-5-mononitrate once daily in angina patients on chronic beta-blockade.

The anti-anginal effect of a controlled-release (Durules) formulation of isosorbide-5-mononitrate (5-ISMN) 60 mg, Imdur, once daily was evaluated in a randomised double-blind, placebo-controlled, crossover study with a placebo run-in period. Each period lasted for 2 weeks. A total of 70 patients (58 men and 12 women) with stable exertional angina pectoris on beta-blockade, mean age 59 years (range 39-71), were included. Exercise testing was performed on a bicycle ergometer 3 hours after the dose at the end of each period. Anginal attacks and intake of sublingual nitroglycerin tablets were noted. Imdur in combination with a beta-blocker significantly increased the total exercise capacity, the time and total work until the onset of chest pain and at 1 mm ST-depression compared with beta-blockade alone. The attack rate and the nitroglycerin consumption were significantly decreased. Headache was the only significant side-effect. In conclusion, the addition of Imdur once daily to beta-blockade significantly increased the anti-anginal effect.

Caries reduction 1.5 years after application of a fissure sealant as related to dietary habits.

Findings 1.5 years after the application of the sealant revealed that among the 200 sealed permanent first molars, 2.5% of the sealants were lost or partly missing, while 95% of the sealants remained in good condition. During the test period, 7 of the 200 sealed permanent fissures had become carious, while 64 of the respective control fissures had decayed. The percentage effectiveness of the prevention by the present method was 85%. Four out of five molars that had lost the sealants became carious, but of the 190 molars having sealants in good condition, only three were diagnosed as carious. All teeth reported as contaminated with saliva at the sealing session had lost the material. No correlation could be found between the type of food eaten or oral hygiene habits of the subjects and the retention of the sealants.