Correlates of low physical activity levels in aging men and women: the DR's EXTRA Study (ISRCTN45977199).

Recognizing correlates of low physical activity (PA) can help in targeting PA interventions for individuals who would benefit most from increasing their PA. We studied the associations of demographic, social, health, and lifestyle factors with low PA by sex in a population sample of 1,303 Finnish individuals aged 57-78 years. We defined low PA as no moderate or vigorous leisure-time PA reported in an interview. Altogether, 39% of men and 48% of women reported low PA. Satisfactory or poor perceived health and high BMI were independently associated with low PA in both sexes. In men, factors such as age, being divorced or separated, still working, having a weak social network, poor diet, and a health professional's suggestion to increase PA were associated with low PA. In women, cardiovascular disease and depressive symptoms were associated with low PA. These results can be applied in targeting PA interventions.

Combined low-saturated fat intake and high fitness may counterbalance diabetogenic effects of obesity: the DR's EXTRA Study.

We report associations of saturated fat (SF) intake with impaired fasting glucose (IFG), impaired glucose tolerance (IGT), concurrent IFG+IGT and type 2 diabetes (T2DM) at different levels of cardiorespiratory fitness and body mass index (BMI). In a population-based sample (n=1261, age 58-78 years), oral glucose tolerance, 4-day food intake and maximal oxygen uptake were measured. High intake of SF (>11.4 E%) was associated with elevated risk for IFG (4.36; 1.93-9.88), concurrent IFG+IGT (6.03; 1.25-29.20) and T2DM (4.77; 1.93-11.82) in the category of high BMI (>26.5) and high fitness, whereas there was no significantly elevated risk in individuals reporting low intake of SF. Concurrent high BMI and low fitness were associated with elevated risks. In general, SF intake and fitness did not differentiate the risk of abnormal glucose metabolism among subjects with low BMI. Limited intake of SF may protect from diabetogenic effects of adiposity, but only in individuals with high level of fitness.

The current standard measure of cardiorespiratory fitness introduces confounding by body mass: the DR's EXTRA study.

OBJECTIVE: Cardiorespiratory fitness is currently estimated by dividing maximal oxygen consumption (VO(2max)) by body weight (per-weight standard). However, the statistically correct way to neutralize the effect of weight on VO(2max) in a given population is adjustment for body weight by regression techniques (adjusted standard). Our objective is to quantify the bias introduced by the per-weight standard in a population distributed across different categories of body mass. DESIGN: This is a cross-sectional study. SUBJECTS AND METHODS: Baseline measures from participants of the Dose-Responses to Exercise Training Study (DR's EXTRA), 635 men (body mass index (BMI): 19-47 kg m⁻²) and 638 women (BMI: 16-49 kg m⁻²) aged 57-78 years who performed oral glucose tolerance tests and maximal exercise stress tests with direct measurement of VO(2max). We compare the increase in VO(2max) implied by the per-weight standard with the real increase of VO(2max) per kg body weight. A linear logistic regression model estimates odds for abnormal glucose metabolism (either impaired fasting glycemia or impaired glucose tolerance or Type 2 diabetes) of the least-fit versus most-fit quartile according to both per-weight standard and adjusted standard. RESULTS: The per-weight standard implies an increase of VO(2max) with 20.9 ml min⁻¹ in women and 26.4 ml min⁻¹ in men per additional kg body weight. The true increase per kg is only 7.0 ml min⁻¹ (95% confidence interval: 5.3-8.8) and 8.0 ml min⁻¹ (95% confidence interval: 5.3-10.7), respectively. Risk for abnormal glucose metabolism in the least-fit quartile of the population is overestimated by 52% if the per-weight standard is used. CONCLUSIONS: In comparisons across different categories of body mass, the per-weight standard systematically underestimates cardiorespiratory fitness in obese subjects. Use of the per-weight standard markedly inflates associations between poor fitness and co-morbidities of obesity.

Diet, fitness and metabolic syndrome--the DR's EXTRA study.

BACKGROUND AND AIMS: To study the independent and combined associations of diet and cardiorespiratory fitness with the prevalence of the metabolic syndrome (MetS). METHODS AND RESULTS: We studied a population-based random sample of 663 men and 671 women 57-78 years of age at baseline of an ongoing randomised controlled trial. Based on a 4-day food record a diet score was created according to goals achieved (vegetables ≥400 g/day, fish ≥2 servings/week, fibre ≥14 g/1000 kcal, saturated fat <10 E%/day). Cardiorespiratory fitness was measured as maximal oxygen uptake (VO(2 max)) in a maximal symptom-limited bicycle ergometer test. MetS was defined by the National Cholesterol Education Program criteria. The lowest prevalence of MetS (5%) was observed among individuals in the highest VO(2 max) tertile and achieving 3-4 dietary goals. The highest prevalence (55%) was observed among those in the lowest VO(2 max) tertile and achieving none of the dietary goals. Among individuals in the highest VO(2 max) tertile, the odds ratio of having MetS was 0.04 (95% CI 0.02-0.10) for those achieving 3-4 dietary goals, 0.07 (0.04-0.14) for those achieving 1-2 dietary goals, and 0.16 (0.07-0.37) for those achieving none of the dietary goals compared with individuals in the lowest VO(2 max) tertile and achieving none of the goals after adjustment for confounding factors. CONCLUSION: Healthy diet and higher levels of cardiorespiratory fitness are associated with a reduced risk of having MetS. However, fitness seems to have a stronger association with MetS than diet.

Cardiorespiratory fitness in aging men and women: the DR's EXTRA study.

The aim of the study was to describe the levels and to create reference values of cardiorespiratory fitness, expressed as maximal oxygen consumption (VO(2max) ), maximal metabolic equivalents (METs) and maximal workload in aging men and women. We measured VO(2max) directly by a breath-by-breath method during a maximal exercise stress test on a bicycle ergometer with a linear workload increase of 20 W/min in a representative population sample of 672 men and 677 women aged 57-78 years. We presented the age and sex-specific categories of cardiorespiratory fitness (very low, low, medium, high and very high) based on variable distribution and non-linear regression models of VO(2max) , maximal METs and maximal workload. The linear age-related decrement of VO(2max) was -0.047 L/min/year (-2.3%) and -0.404 mL/kg/min/year (-1.6%) in men and -0.027 L/min/year (-1.9%) and -0.328 mL/kg/min/year (-1.6%) in women. After exclusion of diseased individuals, the rate of VO(2max) decrement remained similar. The number of chronic diseases (0, 1, 2 or ≥3) was inversely associated with VO(2max) in men (P<0.001) and women (P<0.001). The present study provides clinically useful reference values of cardiorespiratory fitness for primary and secondary prevention purposes in aging people.

Food consumption, nutrient intake and the risk of having metabolic syndrome: the DR's EXTRA Study.

BACKGROUND: The associations of different components of diet with metabolic syndrome (MetS) are largely unknown. We therefore studied the associations of intakes of selected food items and nutrients with the risk of having MetS. METHODS: The participants were a representative population sample of 1334 individuals (671 women, 663 men) 57-78 years of age. Dietary intake was assessed by a 4-day food record. MetS was defined by the National Cholesterol Education Program criteria. RESULTS: Consumption of vegetables, non-root vegetables, legumes and nuts berries and fish had an inverse and consumption of sausage had a direct association with the risk of having MetS in men after adjustment for age, smoking and alcohol consumption. Consumption of vegetables and non-root vegetables had an inverse and consumption of sausage had a direct association with the risk of having MetS in women after these adjustments. However, after further adjustment for maximal oxygen uptake (VO2(max)) most of these associations vanished. Men in the highest third of consumption of berries, fish, and legumes and nuts had 49, 37 and 44% lower risk of having MetS, respectively, than those in the lowest third after further adjustment for VO2(max). Women in the highest third of sausage consumption had a 72% higher risk of having MetS than non-consumers. CONCLUSIONS: Consumption of legumes and nuts, berries and fish was inversely associated with MetS in men. Consumption of sausage was directly associated with MetS in women. VO2(max) seems to be a strong confounding factor between food consumption and MetS.

Electrophysiological properties and expression of the delayed rectifier potassium (ERG) channels in the heart of thermally acclimated rainbow trout.

In ectotherms, compensatory changes in ion channel number and activity are needed to maintain proper cardiac function at variable temperatures. The rapid component of the delayed rectifier K+ current (IKr) is important for repolarization of cardiac action potential and, therefore, crucial for regulation of cellular excitability and heart rate. To examine temperature plasticity of cardiac IKr, we cloned the ether-à-go-go-related gene (ERG) channel and measured its electrophysiological properties in thermally acclimated rainbow trout (Oncorhynchus mykiss; omERG). The present findings demonstrate a complete thermal compensation in the whole cell conductance of the atrial IKr in rainbow trout acclimated to 4 degrees C (cold acclimation) and 18 degrees C (warm acclimation). In situ hybridization indicates that transcripts of the omERG channel are present throughout the muscular tissue of the heart, and quantitative PCR shows increased expression of the omERG in cold-acclimated trout compared with warm-acclimated trout. In both acclimation groups, omERG expression is higher in atrium than ventricle. In addition, the omERG has some functional features that support IKr activity at low temperatures. Voltage dependence of steady-state activation is completely resistant to temperature changes, and steady-state inactivation and activation kinetics are little affected by temperatures below 11 degrees C. Collectively, these findings suggest that high density of cardiac IKr is achieved by cold-induced increase in the number of functional omERG channels and inherent insensitivity of the omERG to temperature below 11 degrees C. These adaptations are probably important in maintaining high heart rates and proper excitability and contractility of trout cardiac myocytes in the cold.

Fish cardiac sodium channels are tetrodotoxin sensitive.

AIM: Sodium current (I(Na)) of the mammalian heart is resistant to tetrodotoxin (TTX) due to low TTX affinity of the cardiac sodium channel (Na(v)) isoform Na(v)1.5. To test applicability of this finding to other vertebrates, TTX sensitivity of the fish cardiac I(Na) and its molecular identity were examined. METHODS: Molecular cloning and whole-cell patch-clamp were used to examine alpha-subunit composition and TTX inhibition of the rainbow trout (Oncorhynchus mykiss) cardiac Na(v) respectively. RESULTS: I(Na) of the trout heart is about 1000 times more sensitive to TTX (IC50 = 1.8-2 nm) than the mammalian cardiac I(Na) and it is produced by three Na(v)alpha-subunits which are orthologs to mammalian skeletal muscle Na(v)1.4, cardiac Na(v)1.5 and peripheral nervous system Na(v)1.6 isoforms respectively. Oncorhynchus mykiss (om) omNa(v)1.4a is the predominant isoform of the trout heart accounting for over 80% of the Na(v) transcripts, while omNa(v)1.5a forms about 18% and omNa(v)1.6a only 0.1% of the transcripts. OmNa(v)1.4a and omNa(v)1.6a have aromatic amino acids, phenylalanine and tyrosine, respectively, in the critical position 401 of the TTX binding site of the domain I, which confers their high TTX sensitivity. More surprisingly, omNa(v)1.5a also has an aromatic tyrosine in this position, instead of the cysteine of the mammalian TTX-resistant Na(v)1.5. CONCLUSIONS: The ortholog of the mammalian skeletal muscle isoform, omNa(v)1.4a, is the predominant Na(v)alpha-subunit in the trout heart, and all trout cardiac isoforms have an aromatic residue in position 401 rendering the fish cardiac I(Na) highly sensitive to TTX.

Association of waist and hip circumference with 12-year progression of carotid intima-media thickness in elderly women.

OBJECTIVE: To test the hypothesis that waist and hip circumferences together provide additional information on the progression of preclinical atherosclerosis beyond either of them alone in elderly women. DESIGN: A 12-year follow-up study. SUBJECTS: A population-based sample of 102 women 60-70 years of age at baseline. MEASUREMENTS: Waist and hip circumferences and body mass index (BMI) were assessed and carotid intima-media thickness (IMT) was quantified noninvasively by ultrasonography. RESULTS: There was a significant increase in the 12-year carotid IMT progression across the thirds of waist circumference (0.080, 0.277, 0.279 mm, P=0.02 for difference) and hip circumference (0.030, 0.342, 0.260 mm, P=0.001 for difference) adjusted for conventional risk factors (age, smoking, systolic blood pressure, serum low-density lipoprotein and high-density lipoprotein cholesterol, blood glucose). The association of waist circumference with IMT progression was not significant after further adjustment for hip circumference or BMI. Further adjustment for waist circumference and BMI did not change the association of hip circumference with IMT progression. The IMT progression was greatest in women with waist circumference >83 cm and hip circumference

Prevention of flower development in birch and other plants using a BpFULL1::BARNASE construct.

The prevention of flower formation is important for avoiding the spread of transgenes from genetically modified plants into wild populations. Moreover, the resources not expended for the generation of flowers and fruits might be allocated to increased vegetative growth. We have been developing methods for preventing flower formation in silver birch (Betula pendula), a tree species of considerable economical importance in the boreal region. Here we study the suitability of the promoter of BpFRUITFULL-LIKE1 (BpFULL1, formerly BpMADS5) for tissue-specific ablation of inflorescences in Arabidopsis, tobacco and birch. With all these species, the development of inflorescences was successfully prevented. The results show that the BpFULL1::BARNASE construct has potential biotechnological applications in different plant species.

Effect of caries in mentally handicapped children of addition of fluoride and bicarbonate-phosphate to dietary sugar products.

Mentally handicapped children, aged 5--15 years and living in institutions, received fluoride supplement in several sugar products of their diet; in candies, marmalades, jams, fruit juices and in sweet desserts corresponding to 10 mg F as NaF per kg of the sugar (sucrose or glucose) of each product. To two of the four daily candies was also added a NaHCO3 + KH2PO4 mixture (mole ratio 9.8/l, resp.) to substitute for 2.5% of the sugar of the candy. The control children received the respective products without the additives. After stepwise exclusions of subjects for various reasons, e.g. for the absence of permanent teeth, low initial caries activity, strong medication, Down's syndrome, etc., the mean DMFS-increment in the remaining 43 control subjects was 4.5 and in the 41 test subjects 2.6 lesions/100 surfaces at risk, i.e. 42% reduction. Caries arrestment had occurred in these test subjects after the first year, while in the respective controls it was continuously increasing. Among numerous oral and body parameters studied, only surface enamel fluoride in primary teeth was increased by the fluoride supplements and urinary phosphate and calcium excretion decreased.