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M Ogren

Publications and source records attributed to M Ogren.

36 records · Page 2Linked to original sources

Methodological aspects for in vitro characterization of receptor binding using 11C-labeled receptor ligands: a detailed study with the benzodiazepine receptor antagonist [11C]Ro 15-1788.

As a complement to in vivo studies with positron emission tomography (PET), it is desirable to perform in vitro characterization of newly developed 11C tracers. In this report we describe the technique for determination of receptor-ligand kinetics utilizing ligands labeled with the short-lived radionuclide 11C. The limitations and advantages are discussed. The benzodiazepine antagonist [11C]Ro 15-1788 was used as a model substance, and the use of storage phosphor plates for quantification of radioactivity was validated. Storage phosphor plates showed an excellent linear range (approximately 10[3]) and acceptable resolution (approximately 0.5 mm). Receptor-ligand kinetics, including depletion, association and dissociation, saturation and displacement were evaluated with good results through the use of short-lived radiotracers and storage phosphor plates.

Animals↗

Increased risk of ischaemic heart disease mortality in elderly men using anxiolytics-hypnotics and analgesics. Results of the 10-year follow-up of the prospective population study "Men born in 1914", Malmo, Sweden.

OBJECTIVES: An increased risk of all-cause and cardiovascular mortality in users of anxiolytic-hypnotic drugs (AHD) has been reported, and use of analgesics may be an additional factor. Therefore, we examined the association of AHD and analgesic use, alone and in combination, with all-cause and ischaemic heart disease (IHD) mortality. METHODS: Multivariate 10-year survival analysis in a population based cohort of 500 men born in 1914. Relative risks (RR) were adjusted by relevant confounders (blood pressure, serum cholesterol, diabetes mellitus, smoking habit, high alcohol consumption, history of previous IHD, cancer, and other diseases). RESULTS: The RR of both all-cause and IHD mortality were significantly increased among those using both AHD and analgesics compared to those who took neither of these drugs: RR = 1.8 for all-cause mortality, and RR = 2.7 for IHD mortality. CONCLUSION: Although the number of cases was small, warranting interpretative caution, the current study suggests that the combined use of AHD (mainly benzodiazepines) and analgesics seems to be associated with an increase in all-cause and IHD mortality in elderly men.

Aged↗

Risk of relapse in new cases of ulcerative colitis and indeterminate colitis.

PURPOSE: Changes in morbidity pattern of ulcerative colitis have created a need to update understanding of the course of the disease. METHOD: A follow-up study was done of relapse rates and progression of inflammation in 571 non-selected patients with ulcerative and indeterminate colitis. RESULTS: Relapse rate ten years after diagnosis was 70 percent in definite ulcerative colitis, 22 percent in probable ulcerative colitis, and 77 percent in indeterminate colitis. During the study period, there was no change in the relapse rate. In relapsing proctitis, 52 percent developed more extensive inflammation. Fifty-four percent of patients with only one attack of colitis had persistent signs of inflammatory bowel disease. CONCLUSIONS: Shift in morbidity pattern to a greater proportion of patients with proctitis at diagnosis and a shorter time from onset of symptoms to diagnosis had no influence on the relapse rate. Indeterminate colitis has a worse prognosis than definite ulcerative colitis. Considering the documented efficacy of sulfasalazine, the high relapse rate calls for studies of the effectiveness of such treatment in everyday practice.

Adolescent↗

Receptor imaging technique with 11C-labeled receptor ligands in living brain slices: its application to time-resolved imaging and saturation analysis of benzodiazepine receptor using [11C]Ro15-1788.

Recently we developed a novel imaging technique using positron emitter-labeled compounds as probes and a storage phosphor screen as a detector. This approach makes it possible to follow a variety of biochemical processes with spatial information in living brain slices. Further technical development is reported here in terms of time-resolved imaging and receptor characterization in a real equilibrium state. The method was validated by use of [11C]Ro15-1788, a benzodiazepine receptor antagonist. Fresh brain slices were incubated with [11C]Ro15-1788 in oxygenated Krebs-Ringer solution at 37 degrees C, in a specially designed chamber. By placing the chamber on a storage phosphor screen, we could obtain two-dimensional images of radioactivity in the slices. Time-resolved imaging was made at 5 min intervals, revealing that it took 60 min to reach equilibrium binding. The dissociation process was observed by adding an excess amount of unlabeled Ro15-1788 to the chamber, 25 min was required for the full dissociation. In the equilibrium state, i.e. in the presence of free radio-ligand, Scatchard plot analysis was performed on the cerebral cortex (Kd = 7.4 nM, Bmax = 146 fmol/mg tissue) and striatum (Kd = 7.5 nM, Bmax = 107 fmol/mg tissue), suggesting the presence of a single component of binding site in these two regions. The present method, for the first time, made it possible to study a ligand-receptor interaction in living brain slices with temporal and spatial resolutions. This technique should prove useful for studies of receptor function under physiological conditions.

Animals↗

Prognosis in elderly men with screening-detected abdominal aortic aneurysm.

OBJECTIVES: To study the natural course of screening-detected symptomless abdominal aortic aneurysm (AAA) in elderly men. SETTING: Malmö, a city in southern Sweden with 230,000 inhabitants and a single referral hospital. MATERIALS: 423 seventy-four-year-old men, randomly selected from the population and belonging to the prospective population study "Men born in 1914", were invited. 343 underwent AAA screening, whereas 80 declined or had moved. CHIEF OUTCOME MEASURES: Five year all cause mortality in relation to participation in and findings at ultrasound screening for AAA. MAIN RESULTS: An abdominal aortic aneurysm was present in 38 (11%) out of 340 men who underwent screening and who had a native aorta. During 5 years of follow-up, one third (13/38) of these men died; 7 from myocardial infarction and 3 from stroke. The mortality rate in men with AAA was 80.2/1000 person years; twice as high as it was in men without AAA (39.4/1000 person years; p = 0.018). Six men underwent AAA surgery. None of them died from aneurysm rupture. However, aneurysm surgery did not reduce the total mortality rate in these men. The highest mortality rate, 91.9/1000 person years, was found in the men who did not participate in the screening. CONCLUSIONS: It is our conclusion that screening for early detection and intervention is of questionable value from a public health perspective.

Aged↗

Catechol-O-methyltransferase inhibition increases the uptake of 11C-3-(3,4-dihydroxyphenyl)-L-alanine in the rat pancreas.

BACKGROUND: The objective of the present investigation was to evaluate the uptake and metabolism of 3-(3,4-dihydroxyphenyl-L-alanine) (L-DOPA) in the rat pancreas. METHODS: The procedure included intravenous injection of the positron-emitting radiotracer L-[beta-11C] DOPA (DOP) into unanaesthetized male Sprague-Dawley rats and evaluation of uptake of radioactivity in organs in animals only given the tracer and in animals given therapeutic doses of three different catechol-O-methyltransferase (COMT) inhibitors, OR-486, OR-611, or Ro 41-0960. Selected pancreati were homogenized, and the chemical form bearing the radioactivity was analysed with high-performance liquid chromatography (HPLC). RESULTS: The main finding was that the tracer uptake in the pancreas increased fourfold when the rats were pretreated with COMT inhibitors. Half maximum effect of OR-486 was found at a dose of 0.2 mg/kg. HPLC analysis showed that with COMT inhibitor, the radioactivity in the pancreas consisted of 90% DOPAC. When administering MAO-A and COMT inhibitor together, the pancreas radioactivity corresponded to dopamine. Also in the pig pancreas a significant increase of DOP was observed after COMT inhibition. CONCLUSIONS: This study has shown a high turnover of L-DOPA in the rat pancreas, which can be modulated to give enhanced levels of DOPAC or dopamine by COMT and MAO inhibition.

Analysis of Variance↗

Operations in unselected patients with ulcerative colitis and indeterminate colitis. A long-term follow-up study.

OBJECTIVE: To assess the need for operative treatment for ulcerative colitis and indeterminate colitis. DESIGN: Retrospective study. SETTING: University Hospital, Sweden. SUBJECT: All patients diagnosed from 1958 to 1982, in Malmö, Sweden-ulcerative colitis (n = 471) and indeterminate colitis (n = 100). MAIN OUTCOME MEASURES: Incidence of colectomy. RESULTS: The mean follow-up was 15 years. The incidence of colectomy was 7.51, 1.90 and 36.13/1000 person years for definite ulcerative colitis, probable ulcerative colitis and indeterminate colitis, respectively. The incidence of colectomy in patients with definite ulcerative colitis in the present study was low compared with other studies. In contrast to other reports, men had a threefold risk while extent of inflammation did not influence the incidence. Patients with indeterminate colitis were a high risk group with a high incidence of colectomy. The high incidence among patients with indeterminate colitis compared with that in patients with definite ulcerative colitis was also seen in subgroups such as patients with total colitis at diagnosis, in patients in remission after the first attack, and in patients with a severe attack. CONCLUSION: As patients with indeterminate colitis seem to be at increased risk of colectomy it could be important to distinguish them from those with ulcerative colitis. Today, however, it is not possible to identify all patients with indeterminate colitis early in the course of the disease.

Adolescent↗

Risk of pancreatic carcinoma in smokers enhanced by weight gain. Results from 10-year follow-up of the Malmö preventive Project Cohort Study.

CONCLUSION: The increased risk of pancreatic carcinoma in smokers is enhanced by weight gain. Possible explanations are proposed and discussed. BACKGROUND: Between 1974 and 1992, 35,000 men and women below 55 yr of age participated in a general health examination at the Department of Preventive Medicine in Malmö, Sweden. Mortality and incidence of cancer have been updated by record linkage with the Cause of Death Register and the National Cancer Register. METHODS: The present study deals with the incidence of pancreatic carcinoma during 365,500 person years of follow-up. The 43 cases corresponded to an incidence per 100,000 person years of 13.4 in men and 6.1 in women. RESULTS: Nonsmokers, exsmokers, and smokers had an incidence of 1.5, 24.5, and 15.3/100,000 person years, respectively. The case-control approach used to assess risk factors for pancreatic carcinoma showed that the odds for smoking (odds ratio [O.R] 8.6; 95% confidence intervals [C.I.] 2.0-37.5), for weight gain more than 10 kg since the age of 30 (O.R. 1.8; 95% C.I. 0.9-3.6), and for epigastric pain (O.R. 3.2; 95% C.I. 1.4-7.2) were higher in cases than in controls. These odds ratios were all statistically significant in the logistic regression analysis.

Adult↗

Biased risk factor assessment in prospective studies of peripheral arterial disease due to change in exposure and selective mortality of high-risk individuals.

BACKGROUND: Our aim was to assess whether risk factor assessment in prospective studies of peripheral disease (PAD) might be biased by change in exposure and selective mortality of individuals at high risk. METHODS: The cohort 'Men born in 1914' has been followed since the baseline examination 1969. PAD, (i.e. ankle-brachial pressure index < 0.9) at the age of 68 was related to risk factors measured at the age of 55 and 68. RESULTS: Hypertension was present in 64% of the men. Of these, 62% were normotensive at 55. Men with hypertension at the age of 55 had lower odds for PAD (odds ratio 1.9; 95% CI 0.8-4.5) than men who were normotensive at 55 (odds ratio 3.0. 95% CI 1.5-6.1). One-third remained smokers at 68; 27% were ex-smokers. The odds for PAD was 3.0 times higher (95% CI 1.4-6.3) in ex-smokers and 2.6 times higher (95% CI 1.3-5.4) in current smokers than in non-smokers. Less than half remained in the same cholesterol quartile. The odds for PAD was 1.5 (95% CI 0.8-2.8) in men with hypercholesterolaemia at 68 and 2.2 (95% CI 1.1-4.7) in men with hypercholesterolemia at both examinations. Smoking and hypertension at the age of 55 were both associated with an increased mortality rate: 26% Of the smokers and 31% of the men with hypertension died before the age of 68. CONCLUSION: Risk factor assessment in prospective studies of PAD is affected by change in exposure and selective mortality of individuals at high risk.

Aged↗

Ten year cerebrovascular morbidity and mortality in 68 year old men with asymptomatic carotid stenosis.

OBJECTIVE: To study the natural course of carotid artery stenosis detected by ultrasonography. DESIGN: Prospective cohort study. Baseline examination in 1982-3 included ultrasound examination of carotid arteries, measurement of ankle-brachial blood pressure index, and detection of atrial fibrillation by 24 hour ambulatory electrocardiography. SETTING: Malmö, a city in southern Sweden with 230,000 inhabitants. SUBJECTS: 470 men aged 68 years randomly selected from the population. MAIN OUTCOME MEASURES: Incidence of stroke and transient ischaemic attack and all cause mortality during 10 years of follow up in relation to carotid stenosis, leg artery disease (ankle-brachial blood pressure index below 0.9), and atrial fibrillation. RESULTS: Fifty men had a stroke; six of these were haemorrhagic. Another 11 had a transient ischaemic attack. Eighteen of the men with carotid stenosis (21.6 events/1000 person years) and 43 of the men with normal carotid arteries (14.8 events/1000 person years) had a stroke or transient ischaemic attack (P = 0.188). Men with atrial fibrillation had an increased rate of cerebrovascular events (36.7/1000 person years (P = 0.048). The highest rate was found in men with asymptomatic disease of the leg arteries (38.6/1000 person years) (P < 0.001). The increased risk of stroke or transient ischaemic attack in this group remained after multivariate analysis (relative risk 2.0; 95% confidence interval 1.1 to 3.7). CONCLUSIONS: In this cohort carotid stenosis was not associated with an increased risk of stroke. Part of this lack of association was explained by the high mortality from ischaemic heart disease in men with severe stenosis. Twenty seven of the 61 cerebrovascular events, however, occurred in men who had normal carotid arteries, normal ankle pressure, and no atrial fibrillation.

Aged↗

Incidence of colorectal cancer and all cause mortality in non-selected patients with ulcerative colitis and indeterminate colitis in Malmö, Sweden.

Cancer morbidity and all cause mortality were studied prospectively in all patients with definite and probable ulcerative colitis and indeterminate colitis diagnosed from 1958 to 1982, in the city of Malmö, Sweden. The follow-up to Jan. 1, 1990 was complete for all but ten patients. Nine of the 471 patients with ulcerative colitis and three of the 100 patients with indeterminate colitis developed colo-rectal cancer. The incidence of colorectal cancer in ulcerative colitis was 1.4 per 1000 person-years. The observed number of cases was 2.1 times higher than expected; (95% C.I. 1.0-4.1), based on the age- and sex-specific cancer incidence in the city during the study period. Indeterminate colitis was associated with a higher colorectal cancer risk than ulcerative colitis; 2.4 per 1000 person-years; (SMR 8.6, 95% C.I. 1.8-25.1). Both conditions were associated with a slight increased mortality rate, for ulcerative colitis 12.6 per 1000 person-years; (SMR 1.3, 95% C.I. 1.0-1.5), and for indeterminate colitis 11.7 per 1000 person-years; (SMR 2.7, 95% C.I. 1.6-4.4). Complications of colitis were the main cause of death in both groups. The cancer risk was related to extent of disease, duration of disease and female gender. Ten out of the 12 cases with cancer had or developed total colitis. However, only seven of the 134 cases with total ulcerative colitis and two of 87 cases with total indeterminate colitis developed cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Plethysmographic pulse wave amplitude and future leg arteriosclerosis.

A low pulse wave amplitude during calf plethysmography at 55 years of age was previously found to be associated with an increased mortality and incidence of myocardial infarction. In order to test the hypothesis that a low pulse wave amplitude is associated with an increased risk of future leg atherosclerosis as well, we have studied the relationship between a low ankle-brachial pressure index (ABPI; < 0.9) at 68 years of age and the pulse wave amplitude at 55 years of age in that same cohort. The prevalence of a low pulse wave amplitude (< or = 5 mm; lowest quintile) among men with a low ABPI (42%) was more than twice as high as it was among men who had a normal ABPI (19%) (P < 0.001). No association was found between a low ABPI and the plethysmographically recorded leg blood flow at 55 years of age. A low pulse wave amplitude might reflect early symptom-free arteriosclerosis, or age-dependent non-arteriosclerotic loss of vessel wall elasticity. The relationship between a low pulse wave amplitude and a low ABPI remained when controlling for smoking, hypertension and hyperlipidaemia. It is concluded that pulse wave measurement by plethysmography contributes information to improve leg atherosclerotic risk assessment in individuals exposed to known risk factors.

Aged↗

Low pulse-wave amplitude during reactive leg hyperaemia: an independent, early marker for ischaemic heart disease and death. Results from the 21-year follow-up of the prospective cohort study 'Men born in 1914', Malmö, Sweden.

OBJECTIVE: To study the incidence of myocardial infarction, all-cause mortality and mortality from ischaemic heart disease in relation to arterial leg blood flow determined by venous occlusion plethysmography of the calf. DESIGN: A prospective cohort study 'Men born in 1914'. SETTING: Malmö, a city in southern Sweden with 256,000 inhabitants, and a single referral hospital. SUBJECTS: Six-hundred and thirty-six 55-year-old men, randomly selected from the general population. None of them had signs or symptoms of leg artery disease. MAIN OUTCOME MEASURES: All-cause mortality, morbidity and mortality from ischaemic heart disease during 21 years of follow-up following the initial examination in 1968. RESULTS: A low pulse-wave amplitude (i.e. < 5 mm) during reactive hyperaemia was, independently of other known arteriosclerotic risk factors, associated with a higher cardiac event rate of 37.1% (relative risk: 2.2; 95% CI: 1.3-3.6) and a higher all-cause mortality rate of 62.9% (relative risk: 1.7; 95% CI: 1.2-2.4) during 21 years of follow-up. No other plethysmographically recorded variable was associated with an increased mortality and cardiac event rate. CONCLUSIONS: The plethysmographically recorded pulse-wave amplitude during reactive hyperaemia can be used as an early independent marker to identify individuals at risk of developing ischaemic heart disease and death at an early age.

Aged↗

Non-invasively detected carotid stenosis and ischaemic heart disease in men with leg arteriosclerosis.

Since the excess mortality rate associated with an ankle-brachial blood-pressure index (ABPI) less than 0.9 was only partly explained by an excess cardiovascular mortality, we believe that leg artery disease should not only be regarded as a marker of generalised arteriosclerosis but also as a sign associated with an increased risk of premature death. 439 men who were part of a prospective population study in Malmö, Sweden, were, at 68 years of age, invited to a health examination including, ABPI, carotid-artery ultrasonography, and 24 h ambulatory electrocardiographic monitoring. Cause-specific mortality and incidence of myocardial infarction (MI) during 8 years of follow-up was compared in men with and without signs of arteriosclerotic disease. Of 60 men with an ABPI < 0.9, 20 (33%) had angina pectoris or previous MI. Another 11 (18%) had silent ST-segment depression (> or = 1 mm); 3 (5%) had a history of stroke; and 17 (28%) had symptom-free carotid stenosis (> 30% reduction of the cross-sectional diameter). Total mortality rate in men with no signs of arteriosclerotic disease was 19.6 per 1000 person-years and cardiac event rate (fatal and non-fatal MI and death from chronic ischaemic heart disease was 8.6 per 1000 person-years). Leg artery disease, carotid stenosis, and ischaemic heart disease were in a univariate analysis all associated with an increased cardiac event rate and an increased total mortality rate. In a multivariate analysis an ABPI less than 0.9 was associated with a 2.4 times higher total mortality (95% CI 1.5-3.9) and a 2.0 times higher cardiac event rate (1.1-3.9). Carotid stenosis and ischaemic heart disease contributed to the risk for MI (RR 2.1; 95% CI 1.2-3.8; and 2.1; 1.2-3.9, respectively), whereas no independent association with total mortality was found.

Aged↗

Low ankle-brachial pressure index in 68-year-old men: prevalence, risk factors and prognosis. Results from prospective population study "Men born in 1914", Malmö, Sweden.

The objectives were to study the distribution of ankle-brachial pressure indices (ABPI) in elderly men in relation to arteriosclerotic risk factors, cardiovascular morbidity and total mortality. The data are taken from the prospective cohort study "Men born in 1914" in Malmö, a city in southern Sweden with 220,000 inhabitants and a single referral hospital. Prevalence of low ABPI (< 0.90) at 68 years of age, total mortality, mortality from ischaemic heart disease (IHD) International Classification of Diseases (ICD) code 410.0-412.9) and cardiac event rate [fatal and non-fatal myocardial infarction (MI) and mortality from chronic ischaemic heart disease] during 8 years of follow-up was measured. Sixty-seven of 477 randomly selected men (14.0%) had an ABPI < 0.90 in one or both legs, 18/477 (3.8%) had intermittent claudication according to the Rose questionnaire, which had a sensitivity of 14.9% and a specificity of 98% when using ABPI as a reference method. Ninety-two per cent of the men with an ABPI < 0.90 were or had been smokers, compared with 80% of the men with an ABPI > or = 0.90. Mean systolic blood pressure and median plasma triglyceride levels were significantly higher in the group with low ABPI. Thirty (45%) of the men with low ABPI and 87 (21%) of the men with pressure indices above 0.90 died during follow-up (p < 0.001). Cardiac event rate was 25% (17/67) in the group with low ABPI and 10% (41/410) in the other group (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗