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T Rissanen

Publications and source records attributed to T Rissanen.

At least 19 recordsLinked to original sources
PubMed2002

Serum fatty acid composition predicts development of impaired fasting glycaemia and diabetes in middle-aged men.

AIMS: Dietary fatty acid intake is reflected in serum fatty acid composition. Studies prospectively investigating serum fatty acids and development of impaired fasting glycaemia (IFG) or diabetes mellitus (DM) are largely lacking. We assessed the association of serum fatty acid composition with development of IFG or DM. METHODS: Middle-aged normoglycaemic men (n = 895) participating in a prospective cohort study were followed up after 4 years. RESULTS: At baseline proportions of serum esterified and non-esterified saturated fatty acids were increased and polyunsaturated fatty acids decreased in men who after 4 years had developed IFG (n = 56) or DM (n = 34). No differences in dietary fatty acid composition as recorded in 4-day dietary records were noted. In logistic regression analyses adjusting for age; obesity; and fasting lipid, glucose and insulin concentrations, men with proportions of non-esterified and esterified linoleate in the upper third had nearly half the risk for IFG or DM compared with the lower third. In covariate analyses, baseline non-esterified linoleate proportions were associated with changes in fasting insulin and glucose concentrations over the 4-year follow-up. Baseline esterified fatty acid composition was also associated with changes in insulin. CONCLUSIONS: High serum linoleate proportions decreased the risk of developing IFG or DM in middle-aged men over a 4-year follow-up, possibly mediated in part by insulin resistance. These findings support recommendations to substitute vegetable fat for animal and dairy fat in the prevention of disturbances of glucose and lipid metabolism.

Adult↗
PubMed2002

Ultrasound-guided percutaneous thoracoabdominal biopsy.

This review will discuss the benefits and disadvantages of ultrasound-guided percutaneous fine-needle aspiration and cutting needle biopsies. Clinical efficacy, cost-effectiveness, some controversies and safety will be reviewed.

Adrenal Glands↗
PubMed2002

Dynamics of contrast enhancement in MR imaging and power Doppler ultrasonography of solid breast lesions.

PURPOSE: To evaluate the dynamics of contrast enhancement in solid breast lesions at contrast-enhanced MR imaging and power Doppler ultrasonography (US) and to compare the methods to histology and to each other. MATERIAL AND METHODS: Forty breast lesions were prospectively examined with dynamic MR and power Doppler US. Time-signal intensity curves of enhancement were obtained for both methods. The shape of the curve was analyzed to be benign, indeterminate or malignant. The curves were also analyzed quantitatively by calculating the slope of the curve and the area under the curve (both methods), relative enhancement (MR), and time to peak (US). The lesions were divided into malignant lesions, fibroadenomas, and other benign lesions. The results were compared to histology. RESULTS: In the subjective analysis of the MR curve in differentiating between benign and malignant lesions the accuracy was 90%. The MR curve also enabled differentiation between fibroadenomas and malignancies. The accuracy of the US curve was 38%. Quantitatively, statistically significant differences were found using all the MR variables, except between malignancies and fibroadenomas. Using the US variables, no significant difference was found between the groups. CONCLUSION: The dynamics of contrast-enhanced MR were reliable in the differential diagnosis of solid breast lesions, but contrast-enhanced power Doppler US was of limited value.

Adult↗
PubMed2001

B-mode, power Doppler and contrast-enhanced power Doppler ultrasonography in the diagnosis of breast tumors.

PURPOSE: To investigate the role of B-mode and unenhanced and enhanced power Doppler ultrasonography (US) in differentiating solid breast lesions, and to find out whether morphologically different tumors differ in terms of vascularity. MATERIAL AND METHODS: Sixty-five lesions, indeterminate or suggestive of malignancy after mammography were prospectively examined with B-mode and unenhanced and enhanced power Doppler US. The lesions were classified as benign, indeterminate or malignant at B-mode, and as benign or malignant at power Doppler US. The results were compared to the histologic diagnoses. Vascularity was analyzed also quantitatively to find out whether threshold values for differential diagnostics could be set. RESULTS: The sensitivity, specificity, and overall accuracy of the morphologic evaluation were 100%, 10%, and 57%, respectively. Rounded lesions were more vascular than spiculated lesions, but vascular assessment was only helpful when it supported a benign morphology. In quantitative analysis, due to the overlap between the benign and malignant lesions, no threshold values could be set. CONCLUSION: Morphologic criteria were useful in characterizing malignant lesions, but the large proportion of indeterminate findings decreased the specificity of US. Neither unenhanced, nor enhanced power Doppler US was able to improve diagnostic accuracy.

Adult↗
PubMed2000

Fish oil-derived fatty acids, docosahexaenoic acid and docosapentaenoic acid, and the risk of acute coronary events: the Kuopio ischaemic heart disease risk factor study.

BACKGROUND: Previous findings concerning the serum levels of fish-derived (n-3) fatty acids and coronary heart disease are inconsistent. The purpose of this study was to investigate the association between the serum n-3 end-product fatty acids docosahexaenoic acid (DHA), docosapentaenoic acid (DPA), and eicosapentaenoic acid and the risk of acute coronary events in middle-aged men. METHODS AND RESULTS: We studied this association in the Kuopio Ischaemic Heart Disease Risk Factor Study, a prospective population study in Eastern Finland. Subjects were randomly selected and included 1871 men aged 42 to 60 years who had no clinical coronary heart disease at baseline examination. A total of 194 men had a fatal or nonfatal acute coronary event during follow-up. In a Cox proportional hazards' model adjusting for other risk factors, men in the highest fifth of the proportion of serum DHA+DPA in all fatty acids had a 44% reduced risk (P=0.014) of acute coronary events compared with men in the lowest fifth. Men in the highest fifth of DHA+DPA who had a low hair content of mercury (</=2.0 microgram/g) had a 67% reduced risk (P=0.016) of acute coronary events compared with men in the lowest fifth who had a high hair content of mercury (>2.0 microgram/g). There was no association between proportion of eicosapentaenoic acid and the risk of acute coronary events. CONCLUSIONS: Our data provide further confirmation for the concept that fish oil-derived fatty acids reduce the risk of acute coronary events. However, a high mercury content in fish could attenuate this protective effect.

Acute Disease↗
PubMed2000

Low serum folate concentrations are associated with an excess incidence of acute coronary events: the Kuopio Ischaemic Heart Disease Risk Factor Study.

OBJECTIVE: To test the hypothesis that low serum folate concentrations are associated with an increased risk of acute coronary events in men free of prior coronary heart disease. SETTING: Research Institute of Public Health, University of Kuopio, Kuopio, Finland. DESIGN: Prospective study in a cohort of 734 men aged 46-64 y examined in 1991-1993 as part of the Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD) and followed for 5 y and 3 months. INTERVENTION: Acute coronary events during the follow-up period were obtained by national hospital discharge registry. Baseline serum folate concentrations were measured by radioimmunoassay. RESULTS: During the follow-up, six (2.5%) men with higher serum folate concentrations (highest third>11.3 nmol/1) and 28 (5.7%) men with lower serum folate (two lowest thirds) developed an acute coronary event (P=0.008). In a Cox model adjusting for age, examination years, and plasma lycopene concentration, in men with higher serum folate concentrations the relative risk for an acute coronary event was 0.31 (95% CI 0.11-0.90, P=0.031) when compared with men with lower serum folates. CONCLUSION: This prospective cohort study in middle-aged men from eastern Finland indicates that moderate-to-high levels of serum folate are associated with a greatly reduced incidence of acute coronary events.

Adult↗
PubMed2000

Antioxidant Supplementation in Atherosclerosis Prevention (ASAP) study: a randomized trial of the effect of vitamins E and C on 3-year progression of carotid atherosclerosis.

OBJECTIVES: To study the efficacy of vitamin E and C supplementation on the progression of carotid atherosclerosis, hypothesizing an enhanced preventive effect in men and in smokers and synergism between vitamins. DESIGN AND SUBJECTS: Double-masked two-by-two factorial trial, randomization in four strata (by gender and smoking status) to receive twice daily either 91 mg (136 IU) of d-alpha-tocopherol, 250 mg of slow-release vitamin C, a combination of these or placebo for three years. A randomized sample of 520 smoking and nonsmoking men and postmenopausal women aged 45-69 years with serum cholesterol >/= 5.0 mmol L-1 were studied. SETTING: The population of the city of Kuopio in Eastern Finland. INTERVENTION: Twice daily either a special formulation of 91 mg of d-alpha-tocopherol, 250 mg of slow-release vitamin C, a combination of these (CellaVie(R)) or placebo for three years. MEASUREMENTS: Atherosclerotic progression, defined as the linear regression slope of ultrasonographically assessed common carotid artery mean intima-media thickness (IMT), was calculated over semi-annual assessments. RESULTS: The average increase of the mean IMT was 0.020 mm year-1 amongst men randomized to placebo and 0.018 mm year-1 in vitamin E, 0.017 mm year-1 in vitamin C and 0.011 mm year-1 in the vitamin combination group (P = 0.008 for E + C vs. placebo). The respective means in women were 0.016, 0.015, 0.017 and 0.016 mm year-1. The proportion of men with progression was reduced by 74% (95% CI 36-89%, P = 0.003) by supplementation with the formulation containing both vitamins, as compared with placebo. CONCLUSIONS: Our study shows that a combined supplementation with reasonable doses of both vitamin E and slow-release vitamin C can retard the progression of common carotid atherosclerosis in men. This may imply benefits with regard to other atherosclerosis-based events.

Aged↗
PubMed2000

Low plasma lycopene concentration is associated with increased intima-media thickness of the carotid artery wall.

Although a number of epidemiological studies have evaluated the association between ss-carotene and the risk of cardiovascular diseases, there has been little research on the role of lycopene, an acyclic form of ss-carotene, with regard to the risk of cardiovascular disease. We investigated the relationship between plasma concentrations of lycopene and intima-media thickness of the common carotid artery wall (CCA-IMT) in 520 middle-aged men and women (aged 45 to 69 years) in eastern Finland. They were examined from 1994 to 1995 at the baseline of the Antioxidant Supplementation in Atherosclerosis Prevention (ASAP) study, a randomized trial concerning the effect of vitamin E and C supplementation on atherosclerotic progression. The subjects were classified into 2 categories according to the median concentration of plasma lycopene (0.12 micromol/L in men and 0.15 micromol/L in women). Mean CCA-IMT of the right and left common carotid arteries was 1.18 mm in men and 0.95 mm in women with plasma lycopene levels lower than the median and 0.97 mm in men (P:<0.001 for difference) and 0.89 mm in women (P:=0.027 for difference) with higher levels of plasma lycopene. In ANCOVA adjusting for cardiovascular risk factors and intake of nutrients, in men, low levels of plasma lycopene were associated with a 17.8% increment in CCA-IMT (P:=0.003 for difference). In women, the difference did not remain significant after the adjustments. We conclude that low plasma lycopene concentrations are associated with early atherosclerosis, manifested as increased CCA-IMT, in middle-aged men living in eastern Finland.

Age Factors↗
PubMed1999

Effect of an internal carotid stenosis on orbital blood velocity.

PURPOSE: To examine how an internal carotid artery (ICA) stenosis influences the orbital blood velocity and to determine which velocity parameters are most useful. MATERIAL AND METHODS: The study group comprised 94 randomly selected patients examined with orbital US; most of the patients had a carotid artery stenosis. There were 58 men and 36 women, ranging in age from 22 to 88 years with a mean age of 63.1 years. The ICA stenosis grade was determined with carotid US. Peak systolic (Vp) and end-diastolic blood velocities, systolic acceleration, mean velocity, pulsatile index (PI) and resistance index (RI) were measured within the central retinal artery (CRA) and the ophthalmic artery (OA), and peak velocity was measured within the central retinal vein (CRV). The area under the ROC curve was used to compare the outcome of diagnostic tests. RESULTS: Only a severe (> or =80%) ICA stenosis decreased orbital blood velocity significantly, while milder stenoses did not cause significant flow decrease or side differences. According to ROC curve analysis, the threshold values giving the highest accuracy in detecting a > or =80% ICA stenosis were Vp < or =0.08 cm/s for the CRA and Vp < or =0.14 cm/s for the OA. The sensitivities for detecting a > or =80% ICA stenosis were 45% for Vp CRA and 60% for Vp OA. Systolic acceleration also decreased in severe stenoses, but RI, PI and velocity in the CRV did not correlate with ICA pathology. Reversal of OA flow was seen in 92% of ICA occlusion and in 47% of severe ICA stenosis. CONCLUSION: Orbital Doppler combined with carotid Doppler can be helpful in the diagnosis of the ocular ischaemic syndrome and in the evaluation of whether the symptoms are related to occlusion of the ophthalmic or central retinal vessels or are a consequence of carotid artery stenosis.

Adult↗
PubMed1998

Ultrasonography of invasive lobular breast carcinoma.

PURPOSE: To review the US findings in invasive lobular breast carcinoma which is often difficult to diagnose clinically and mammographically. MATERIAL AND METHODS: The mammographic and US findings in 63 cases of pure invasive lobular carcinoma diagnosed at our institution in 1990-1996 were reviewed retrospectively. The US findings were classified as positive, negative or indeterminate for malignancy. RESULTS: Forty-nine of the 63 lobular carcinomas (78%, 95% CI 65.5-87.3%) were US-positive, and 51 (81%, CI 95% 69.1-89.8%) were mammography-positive. The US visibility of the carcinomas was affected by their palpability and mammographic appearance, and the radiographic density of the breasts. Indeterminate US findings (architectural distortion with acoustic shadowing) were visualized in 4 of the 10 cases that had asymmetric densities at mammography. CONCLUSION: The sensitivity of US for lobular carcinoma was not statistically different from that of mammography. The methods were complementary, especially with regard to evaluating dense breasts and lesions which were difficult to assess clinically and mammographically.

Adult↗
PubMed1998

Ultrasonography as a guidance method in the evaluation of mammographically detected nonpalpable breast lesions of suspected malignancy.

PURPOSE: To evaluate the role of ultrasonography (US) as a method of guidance for fine-needle aspiration biopsy or preoperative wire localization in the demonstration of nonpalpable mammographically detected breast lesions. MATERIAL AND METHODS: A total of 168 nonpalpable mammographically detected breast lesions were examined by means of high-resolution real-time US. RESULTS: US depicted: 55% of all the lesions (92/168); 88% of the circumscribed densities (45/51); 80% of the stellate densities (35/44); 47% of the asymmetric densities (7/15); and 9% of the microcalcifications (5/58). CONCLUSION: US was useful in guiding needle biopsy or wire localization in most of the circumscribed and stellate breast lesions, even in fatty breasts. However, with the equipment that is currently available, US was of no value in localizing microcalcifications.

Adult↗
PubMed1997

Incorporation of n-3 fatty acids into plasma lipid fractions, and erythrocyte membranes and platelets during dietary supplementation with fish, fish oil, and docosahexaenoic acid-rich oil among healthy young men.

The effects of n-3 fatty acid supplementation in the form of fresh fish, fish oil, and docosahexaenoic acid (DHA) oil on the fatty acid composition of plasma lipid fractions, and platelets and erythrocyte membranes of young healthy male students were examined. Altogether 59 subjects (aged 19-32 yr, body mass index 16.8-31.3 kg/m2) were randomized into the following diet groups: (i) control group; (ii) fish diet group eating fish meals five times per week [0.38 +/- 0.04 g elcosapentaenoic acid (EPA) and 0.67 +/- 0.09 g DHA per day]; (iii) DHA oil group taking algae-derived DHA oil capsules (1.68 g/d DHA in triglyceride form); and (iv) fish oil group (1.33 g EPA and 0.95 g DHA/d as free fatty acids) for 14 wk. The fatty acid composition of plasma lipids, platelets, and erythrocyte membranes was analyzed by gas chromatography. The subjects kept 4-d food records four times during the study to estimate the intake of nutrients. In the fish diet, in DHA oil, and in fish oil groups, the amounts of n-3 fatty acids increased and those of n-6 fatty acids decreased significantly in plasma lipid fractions and in platelets and erythrocyte membranes. A positive relationship was shown between the total n-3 polyunsaturated fatty acids (PUFA) and EPA and DHA intake and the increase in total n-3 PUFA and EPA and DHA in all lipid fractions analyzed. DHA was preferentially incorporated into phospholipid (PL) and triglyceride (TG) and there was very little uptake in cholesterol ester (CE), while EPA was preferentially incorporated into PL. and CE. The proportion of EPA in plasma lipids and platelets and erythrocyte membranes increased also by DHA supplementation, and the proportion of linoleic acid increased in platelets and erythrocyte membranes in the DHA oil group as well. These results suggest retroconversion of DHA to EPA and that DHA also interferes with linoleic acid metabolism.

Adult↗
PubMed1995

Low-cost digital teleradiology.

A teleradiology link based on standard personal computers and a flat-bed CCD scanner was tested. A 64 kbit/s dial-up digital ISDN telephone line was used for transmission. A total of 254 films (174 uncompressed, 80 compressed) were sent. Ninety-six per cent of the uncompressed images and 98% of the compressed images were considered technically acceptable. The total diagnostic agreement between the acceptable transmitted images and the original films was 98%. Image quality was sufficient for diagnosis in CT and conventional chest and bone radiographs. However, a 256-step gray scale of the scanner was not sufficient for demanding situations, such as overexposed images with a high contrast gradient. The average speed of transmission was 60 kbit/s, which was considered adequate. The tested system suggests that a teleradiology link based on standard personal computers and programs works in situations where instant consultation is needed. However, the image digitization time with the prototype system was quite long, and a better user interface is under development.

Microcomputers↗
PubMed1993

Ultrasound-guided percutaneous galactography.

We present a new percutaneous ultrasound-guided galactography technique that may be used in patients in whom the conventional technique fails and breast ultrasonography show dilated ducts.

Aged↗