Georg Alfthan

National Institute for Health and Welfare, Finland, Helsinki, Uusimaa, Finland

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Publications (200)909.59 Total impact

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    Full-text · Article · Feb 2016 · PLoS ONE
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    ABSTRACT: Micronutrient deficiencies can damage the health of adolescent girls and their offspring. There is a lack of population-based data on the micronutrient status of adolescents in Sub-Saharan Africa. We conducted a cross-sectional, population-based study to examine the biochemical status, prevalence of deficiency, dietary intake, and food sources of selected micronutrients among adolescent girls in Central Mozambique. Separate groups of study participants were recruited in 2 seasons in 2010. The participants were girls between 14 and 19 years of age (n = 551) from 1 urban area and 2 rural districts. Micronutrient status indicators were analyzed from blood and urine samples. Twenty-four-hour dietary recalls were also carried out. The overall prevalence with 95% confidence interval (calculated using sampling weights) among nonpregnant girls was 42.4% (37.2%-47.8%; n = 466) for anemia, 27.4% (23.1%-32.2%; n = 427) for low serum ferritin, 32.7% (27.7%-38.1%; n = 423) for low serum zinc, 14.7% (11.2%-19.0%; n = 426) for low plasma retinol, and 4.1% (2.9%-5.8%; n = 448) for low serum folate. The selenium status was considered sufficient. Mild to moderate iodine deficiency was found in the rural districts, whereas the iodine status of urban girls was adequate. Significantly lower serum folate concentrations were found in the urban area compared to the rural districts. The seasonal differences in vitamin A intake were significant. The intakes of micronutrients from animal source foods were small. In summary, adolescent Mozambican girls are at risk of several micronutrient deficiencies. This raises concern especially because adolescent motherhood is common in the region. Actions need to be taken to prevent and control micronutrient deficiencies. Copyright © 2015. Published by Elsevier Inc.
    No preview · Article · May 2015 · Nutrition research

  • No preview · Article · May 2015 · Nutrition Research
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    ABSTRACT: Despite different geological features the Nordic countries are generally selenium-poor areas. In each country various factors such as food importation and life-style determine the selenium (Se) intake. Due to an extremely low Se intake in the 1970s in Finland, 0.025 mg/day, an official decision was made in 1984 to supplement multinutrient fertilizers with Se in the chemical form of sodium selenate. Almost all fertilizers used in Finland since 1985 have contained Se. Currently all crop fertilizers contain 15 mg Se/kg. Finland is still the only country to take this country-wide measure.
    No preview · Article · May 2014 · Journal of Trace Elements in Medicine and Biology
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    ABSTRACT: BACKGROUND: Prospective studies investigating the role of serum vitamin E concentrations during early life in the development of childhood allergies and asthma are limited. OBJECTIVE: To study the associations between serum vitamin E concentrations at first year of life and longitudinal development of atopy, atopic dermatitis, wheeze, and asthma up to 6 years of age. METHODS: The setting was the PASTURE study, a multicenter prospective birth cohort study in five European rural settings. Children of 1133 mothers recruited during pregnancy were followed from birth with measurement of serum vitamin E levels at year 1 and repeated assessments of serum immunoglobulin E antibodies (year 1, 4.5, 6), atopic dermatitis, wheezing symptoms, and asthma (year 1, 1.5, 2, 3, 4, 5, 6). RESULTS: At 6 years of age, 66% and 82% of the original 1133 subjects underwent blood test for IgE and answered the questionnaire, respectively. We did not observe any statistically significant associations between serum vitamin E concentrations at year 1 and the endpoints, but borderline inverse associations between alpha tocopherol and wheezing without cold (OR 0.45, 95% CI 0.19-1.09) and any wheezing symptom (OR 0.52, 95% CI 0.27-1.02). CONCLUSIONS: Serum vitamin E concentrations at year 1 were not associated with allergies or asthma by 6 years of age. While further prospective studies with repeated assessments of vitamin E during early life may clarify its putative role in the development of the diseases, it is also possible that the antioxidant hypothesis in the development of allergies and asthma does not hold.
    Full-text · Article · Nov 2013 · Allergy
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    ABSTRACT: Chronic infections have been demonstrated to maintain low-grade systemic inflammation and associate with atherosclerosis. We studied the inflammation- and lipid homeostasis-related effects of Aggregatibacter actinomycetemcomitans (Aa) and Chlamydia pneumoniae (Cpn) infections on the epididymal and inguinal adipose tissue (AT) transcriptomes and fatty acid distribution in apolipoprotein (apo) E-deficient mice. Chow-fed apoE-deficient mice were exposed to 1) chronic intranasal infection with C. pneumoniae (Cpn group), 2) recurrent intravenous infection with A. actinomycetemcomitans (Aa group), 3) a combination of both types of infection (Cpn + Aa group), or 4) infection with the vehicle (control group). Epididymal and inguinal AT gene expression was analyzed using an Illumina Mouse WG-6 v2.0 platform and quantitative PCR (QPCR). Microarray data were analyzed using Gene Ontology enrichment analysis. AT fatty acid analysis was performed using gas--liquid chromatography. The transcriptomics data revealed significant enrichment in inflammation-associated biological pathways in both AT depots derived from the Aa and Cpn + Aa treated mice compared with the control group. The proportion of saturated fatty acids was higher in the inguinal AT in Aa (p = 0.027) and Cpn + Aa (p = 0.009) groups and in the epididymal AT in Aa group (p = 0.003). The proportion of polyunsaturated fatty acids was significantly lower among all Aa-infected groups in both depots. Chronic Cpn infection displayed only minor effects on transcriptomics and fatty acids of the AT depots. Systemic infection with A. actinomycetemcomitans activates inflammation-related biological pathways and modulates cellular lipid homeostasis. The adverse changes in adipose tissues during chronic infection may promote atherosclerosis.
    Full-text · Article · Oct 2013 · BMC Genomics
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    ABSTRACT: To examine (i) whether the consumption of fresh vegetables, fruit and berries is associated with plasma vitamin C concentration and (ii) educational differences in plasma vitamin C concentration in two neighbouring areas in Russia and Finland. Cross-sectional risk factor surveys in 1992, 1997 and 2002. Logistic regression analysis was applied to examine the associations of consumption of selected foods and education with plasma vitamin C concentration. District of Pitkäranta in the Republic of Karelia, Russia and North Karelia, Finland. Adults aged 25-64 years: 579 men and 612 women in Pitkäranta; 974 men and 642 women in North Karelia. The plasma vitamin C concentration was strikingly low in Pitkäranta, Russia across the study years. During the 10 years of monitoring, the mean plasma vitamin C concentration among men ranged from 2·5 to 8·0 μmol/l in Pitkäranta, Russia and from 27·1 to 53·9 μmol/l in North Karelia, Finland. In both areas, daily consumption of fruit was most strongly associated with plasma vitamin C, while the association of fresh vegetable consumption with plasma vitamin C was less consistent. Consumption of berries was less important in explaining plasma vitamin C. In Pitkäranta, the plasma vitamin C concentration was lower among respondents in the lowest education group. Differences in the consumption of fresh vegetables and fruit resulted in notable differences in vitamin C status between Pitkäranta and North Karelia in spring. In comparative settings, knowledge of local food culture and validation pilots are important before conducting large population surveys.
    Preview · Article · Aug 2013 · Public Health Nutrition
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    ABSTRACT: Aims: The purpose of this study was to identify novel genetic variants influencing circulating asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) levels and to evaluate whether they have a prognostic value on cardiovascular mortality. Methods and results: We conducted a genome-wide association study on the methylarginine traits and investigated the predictive value of the new discovered variants on mortality. Our meta-analyses replicated the previously known locus for ADMA levels in DDAH1 (rs997251; P = 1.4 × 10(-40)), identified two non-synomyous polymorphisms for SDMA levels in AGXT2 (rs37369; P = 1.4 × 10(-40) and rs16899974; P = 1.5 × 10(-38)) and one in SLC25A45 (rs34400381; P = 2.5 × 10(-10)). We also fine-mapped the AGXT2 locus for further independent association signals. The two non-synonymous AGXT2 variants independently associated with SDMA levels were also significantly related with short-term heart rate variability (HRV) indices in young adults. The major allele (C) of the novel non-synonymous rs16899974 (V498L) variant associated with decreased SDMA levels and an increase in the ratio between the low- and high-frequency spectral components of HRV (P = 0.00047). Furthermore, the SDMA decreasing allele (G) of the non-synomyous SLC25A45 (R285C) variant was associated with a lower resting mean heart rate during the HRV measurements (P = 0.0046), but not with the HRV indices. None of the studied genome-wide significant variants had any major effect on cardiovascular or total mortality in patients referred for coronary angiography. Conclusions: AGXT2 has an important role in SDMA metabolism in humans. AGXT2 may additionally have an unanticipated role in the autonomic nervous system regulation of cardiac function.
    Full-text · Article · Feb 2013 · European Heart Journal
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    ABSTRACT: European Journal of Clinical Nutrition is a high quality, peer-reviewed journal that covers all aspects of human nutrition.
    No preview · Article · Nov 2012 · European journal of clinical nutrition
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    ABSTRACT: Background: High-density lipoprotein cholesterol (HDL-C) is important in risk assessment for cardiovascular disease or metabolic syndrome; however, different direct HDL-C assays may lead to erroneous risk estimates and potentially misclassify people. Methods: Data for 30-year HDL-C trends in Finland were obtained from the national FINRISK surveys during 1982-2012 (n=45766) taking into account biases from three external quality assessment programs (EQA). We also compared two different direct HDL-C and turbidimetric apolipoprotein A-I methods using 413 fresh serum samples. Results: HDL-C concentrations in the Finnish population were on average 1.33 (±0.04) mmol/l for men and 1.62 (±0.05) mmol/l for women after bias-correction. Positive HDL-C trends were observed for both sexes with original data, but trends disappeared after bias-correction. Comparison of two direct HDL-C methods demonstrated concentration-dependent difference. When HDL-C concentrations were <1.0 mmol/l, the mean bias was -12.0% (95% CI -13.5 to -10.0) whereas HDL-C concentrations >1.55 mmol/l showed mean bias of 9.0% (95% CI 7.0-10.5). Conclusions: Accurate reporting of HDL-C concentrations at the population level requires proper and regular attendance to reliable EQA programs. We found evidence for a concentration-dependent difference between some direct HDL-C methods, which may cause misclassification of people in cardiovascular risk assessment.
    No preview · Article · Oct 2012 · Clinica chimica acta; international journal of clinical chemistry
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    ABSTRACT: For 32 districts of Omsk oblast, the levels of selenium accumulation were determined across trophic levels: soil, plants, animals, and human. An inverse correlation was found between serum selenium concentration and parameters of total mortality, as well as the incidence of lung, ovarian, and rectal cancer. Significant differences were shown in the coefficient of plant selenium accumulation depending on the soil type. We discuss the most promising approaches to optimizing the selenium status of the population.
    No preview · Article · May 2012 · Contemporary Problems of Ecology
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    ABSTRACT: Oxidatively modified LDL particles contribute to atherogenic development and therefore dietary interventions for promoting oxidation resistance of LDL are of interest. The capacity of LDL to resist oxidation can be determined ex vivo by exposing isolated LDL particles to copper ions and measuring the formation of conjugated dienes by spectrophotometry. The aim of this trial was to determine the effect of none versus high intake of rye bread on the oxidation resistance of LDL in healthy humans while otherwise on habitual diet. Sixty-three healthy subjects excluded rye products for one week (baseline), followed by a stepwise addition of rye bread from 99 g/d during the first two weeks to 198 g/d during the following two weeks. Additionally plant sterols were incorporated into the rye bread for half of the subjects to study cholesterol-lowering. The resistance of LDL against copper-induced oxidation was determined at baseline and at the end of the rye-period by monitoring formation of conjugated dienes. We observed a significant increase in the oxidation resistance of LDL, determined as a prolongation of the lag time (P < 0.001) and decrease in the slope of the propagation phase (P = 0.048) from baseline to the end of the rye-period without changes in vitamin E concentration. We observed no significant differences in the oxidation resistance of LDL between subjects who did or did not receive plant sterols. Rye bread intake improved significantly the oxidation resistance of LDL. Further studies are needed to clarify the protective mechanism(s).
    No preview · Article · Jan 2012 · Atherosclerosis
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    ABSTRACT: Fatty acid concentrations in blood are potential biomarkers of dietary fat intake, but methodological studies among children are scarce. The large number of fatty acids and their complex interrelationships pose a special challenge in research on fatty acids. Our target was to assess the interrelationships between the total fatty acid profiles in diet and serum of young children. The study subjects were healthy control children from the birth cohort of the Type 1 Diabetes Prediction and Prevention Study. A 3-day food record and a frozen serum sample were available from 135 children at the age of 1 year, from 133 at 2 years, and from 92 at 3 years. The relationship between dietary and serum fatty acid profiles was analysed using canonical correlation analysis. The consumption of fatty milk correlated positively with serum fatty acids, pentadecanoic acid, palmitic acid and conjugated linoleic acid (CLA) at all ages. Correlations between dietary and serum eicosapentaenoic and/or docosahexaenoic acid were observed at 2 and 3 years of age. Serum linoleic acid was positively associated with the consumption of infant formula at the age of 1 year, and with the consumption of vegetable margarine at 2 and 3 years. The results indicate a high quality of the 3-day food records kept by parents and other caretakers of the children, and suitability of non-fasting, un-fractioned serum samples for total fatty acid analyses. The correlation between intake of milk fat and serum proportion of CLA is a novel finding.
    No preview · Article · Nov 2011 · Maternal and Child Nutrition
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    ABSTRACT: For practical reasons it is not easy to obtain fasting samples in large population health surveys. Non-fasting triglyceride (Tg) values are difficult to interpret. The authors compared the accuracy of statistically corrected non-fasting Tg values with true fasting values and estimated the misclassification of subjects with high low-density lipoprotein cholesterol (LDL-C) and the metabolic syndrome. Non-fasting blood was obtained from a population-based sample of 4282 individuals aged 24-75 years in the National FINRISK 2007 Study. Fasting blood samples were drawn from the same persons 3 months later. Non-fasting serum Tg values were converted into fasting values using previously published formula. LDL-C was calculated and classification of the metabolic syndrome was carried out according to three different latest guidelines. The median (25th, 75th percentile) non-fasting serum Tg concentration was 1.18 (0.87, 1.72) mmol/L and after postprandial correction 1.06 (0.78, 1.52) mmol/L. The true-fasting serum Tg concentration was 1.00 (0.75, 1.38) mmol/L (P < 0.001) vs. non-fasting and corrected value. Bias of the corrected value was +5.9% compared with the true-fasting Tg. Of the true fasting subjects, 56.4% had LDL-C ≥ 3.00 mmol/L. When calculated using non-fasting serum Tg, the prevalence of high LDL-C was 51.3% and using statistically corrected Tg it was 54.8%. The prevalence of metabolic syndrome was 35.5% among fully fasted persons and among non-fasting subjects 39.7%, which after statistical correction of Tg decreased to 37.6% (P < 0.001 for all comparisons). Correction of non-fasting serum Tg to fasting values plays a minor role in population studies but nevertheless reduces misclassification of calculated high LDL-C from 5.1 to 1.6% and the metabolic syndrome from 4.2 to 2.1%.
    Full-text · Article · May 2011 · BMC Medical Research Methodology
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    ABSTRACT: Concern has been recently raised about possible adverse cardio-metabolic effects of high selenium status, such as increased risks of diabetes and hyperlipidaemia. However, most of the evidence comes from selenium-replete populations such as that of the United States. To examine cross-sectional and longitudinal associations of serum selenium with cardiovascular risk factors in Finland where selenium levels were amongst the lowest in the world until the early 1980s before the implementation of a nationwide selenium fertilization programme. Serum selenium was measured in 1235 young Finns aged 3-18 years at baseline in 1980 (prefertilization) and in a subgroup (N = 262) at the 6-year follow-up (1986, postfertilization). During the 27-year follow-up, serum lipids, blood pressure, body mass index and smoking were assessed five times (1980, 1983, 1986, 2001 and 2007). Mean (±SD) serum selenium concentrations were 74.3 ± 14.0 ng mL(-1) in 1980 and 106.6 ± 12.5 ng mL(-1) in 1986 (average increase 32.3 ng mL(-1); 95% CI: 30.3 to 34.3, P < 0.0001). In univariate and multivariable cross-sectional models in 1980 and 1986, increased serum selenium levels were consistently associated with increased total, HDL and Low-density lipoprotein (LDL) cholesterol. However, the average longitudinal changes in lipids were -0.20 mmol L(-1) (95% CI: -0.30 to -0.10, P < 0.0001) for total cholesterol, 0.06 mmol L(-1) (95% CI: 0.03 to 0.10, P < 0.0001) for HDL cholesterol, and -0.23 mmol L(-1) (95% CI: -0.31 to -0.14, P < 0.0001) for LDL cholesterol. Selenium measured in 1986 was not associated with lipids assessed in 2001 and 2007. Cross-sectional findings from the Young Finns study corroborate positive associations of selenium status with serum lipids. However, longitudinal evidence does not support the causality of this link.
    Full-text · Article · May 2011 · Journal of Internal Medicine
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    ABSTRACT: In addition to traditional measurements of serum lipid levels, apolipoprotein A-I (apoA-I), apolipoprotein B (apoB), and apoB/apoA-I ratio may add more value to risk assessment guidelines for cardiovascular disease. We calculated reference intervals for apoA-I, apoB, and apoB/apoA-I ratio using a reference sample (n=2828) from the FINRISK 2007 study. The reference intervals for apoA-I were 1.1-2.0 g/l for men and 1.2-2.3 g/l for women. The corresponding reference intervals for apoB were 0.6-1.5 g/l and 0.6-1.3 g/l. The reference intervals for apoB/apoA-I ratio were 0.3-1.0 for men and 0.3-0.8 for women. Compared with the healthy reference group, obese men had the lowest ApoA-I, the highest apoB, and the highest apoB/apoA-I ratio. Men with CVD and cholesterol-lowering medication, or diabetes had lower apoB levels and apoB/apoA-1 ratio than the reference group but the opposite was true for women. The therapeutic goal for low-risk individuals for apoB was 0.9 g/l coinciding with LDL-C concentration of 3.0 mmol/l. Reference intervals for apoA-I, apoB, and the apoB/apoA-I ratio and their cutoff values may be useful for the risk evaluation and follow-up of treatment among individuals having CVD or other metabolic disorders.
    No preview · Article · Mar 2011 · Clinica chimica acta; international journal of clinical chemistry
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    U Schwab · G Alfthan · A Aro · M Uusitupa

    Full-text · Article · Mar 2011 · European journal of clinical nutrition
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    ABSTRACT: Plant sterols are naturally occurring cholesterol-lowering compounds which are industrially incorporated in various foods. A novel food carrier is rye bread, the intake of which can be monitored in trials utilizing newly defined plasma biomarkers. Our aim was to determine the effects of plant sterols incorporated into high-fiber rye bread on serum total and LDL cholesterol, apoB/apoA1 and total cholesterol/HDL cholesterol ratios and lipophilic (pro)vitamins in healthy free-living normocholesterolemic individuals. In this double-blind, dietary intervention trial the subjects (n=68) were randomized to receive a rye bread (9.3g/d fiber) with added plant sterols (2g/d) (active) or without (control). In the second phase of the study the amount of rye bread was doubled providing 18.6g/d fiber and in the active group 4g/d plant sterols. Compliance was monitored utilizing 3-day food diaries and a novel rye fiber-derived biomarker in plasma. Intake of rye bread enriched with 2g/d of plant sterols during two weeks reduced significantly serum total and LDL cholesterol, apoB/apoA1 and total cholesterol/HDL cholesterol ratios by 5.1%, 8.1%, 8.3% and 7.2%, respectively, compared to controls. Correspondingly, the following two-week treatment with 4g/d of plant sterols resulted in 6.5%, 10.4%, 5.5% and 3.7% difference compared to controls, being most pronounced for LDL (0.33 mmol/L). The treatments did not affect lipophilic (pro)vitamin levels. Rye bread enriched with 2-4g/d of nonesterified plant sterols beneficially modifies cardiovascular lipid risk factors in normocholesterolemic subjects compared to controls.
    Full-text · Article · Jan 2011 · Nutrition, metabolism, and cardiovascular diseases: NMCD
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    Full-text · Article · Jan 2011 · Journal of Internal Medicine
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    ABSTRACT: Aim. - Reactive oxygen intermediates have been implicated in mediating the destruction of insulin-producing beta cells and antioxidant nutrients thought to protect against such a process. This study aimed to assess the associations between serum alpha- and beta-carotene concentrations, and the risk of advanced beta-cell autoimmunity, in children with HLA-conferred susceptibility to type 1 diabetes. Methods. - This case-control study, comprising 108 case children with advanced beta-cell autoimmunity and 216 matched control children, was nested within the nutrition study of the Type 1 Diabetes Prediction and Prevention (DIPP) birth cohort. Serum alpha- and beta-carotene samples were collected each year from the age of 1 to 6 years. For each case-control group, serum samples were analyzed up to the time of seroconversion in the case children. Associations were studied using a conditional logistic-regression model. Results. - Neither serum alpha- nor beta-carotene concentration was significantly associated with the risk of advanced beta-cell autoimmunity. There was marginal evidence (P = 0.049) of an inverse association between serum beta-carotene concentration and the risk of developing advanced beta-cell autoimmunity at a time closest to seroconversion after adjusting for parental education, maternal age, duration of gestation, diabetes in first-degree relatives, number of earlier deliveries and maternal smoking during pregnancy. Conclusion. - The present study data provided no clear evidence to support an association between serum alpha- or beta-carotene concentration and advanced beta-cell autoimmunity.
    No preview · Article · Jan 2011

Publication Stats

9k Citations
909.59 Total Impact Points


  • 1998-2015
    • National Institute for Health and Welfare, Finland
      • • Department of Chronic Disease Prevention
      • • Disease Risk Unit
      Helsinki, Uusimaa, Finland
  • 1983-2009
    • University of Helsinki
      • • Institute of Dentistry
      • • BioMag Laboratory
      • • Department of Oral Medicine
      Helsinki, Southern Finland Province, Finland
  • 1982-2009
    • National Public Health Institute
      Helsinki, Uusimaa, Finland
  • 2006
    • University of Tampere
      Tammerfors, Province of Western Finland, Finland
  • 1985-2004
    • University of Kuopio
      • • Department of Public Health and General Practice
      • • Department of Biochemistry
      Kuopio, Northern Savo, Finland
  • 1996
    • Vrije Universiteit Brussel
      Bruxelles, Brussels Capital, Belgium
  • 1994
    • Kela - The Social Insurance Institution of Finland
      • Research Department
      Helsinki, Uusimaa, Finland
  • 1992
    • Uppsala University
      • Center for Police Research
      Uppsala, Uppsala, Sweden
  • 1990
    • Finnish Cancer Registry, Helsinki
      Helsinki, Southern Finland Province, Finland
  • 1989
    • University of Oulu
      • Department of Public Health Science and General Practice
      Uleoborg, Northern Ostrobothnia, Finland
  • 1984
    • Central Hospital Central Finland
      Jyväskylä, Province of Western Finland, Finland