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1.
Zookeys ; (547): 93-102, 2015.
Article in English | MEDLINE | ID: mdl-26798316

ABSTRACT

The genus Acronymolpus is proposed as new. It is represented by four new species, all of which are endemic to New Caledonia. Proposed are: Acronymolpus joliveti sp. n. (type species), Acronymolpus gressitti sp. n., Acronymolpus meteorus sp. n., and Acronymolpus turbo sp. n.

2.
Eur J Clin Nutr ; 69(7): 837-42, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25514897

ABSTRACT

BACKGROUND/OBJECTIVES: The prevalence of obesity, defined as body mass index (BMI) ⩾30 kg/m(2), differs between populations; however, there is a need for data on description on body composition in reference populations of different ages and from different countries. The objective of this study was to pool dual-energy X-ray absorptiometry (DXA) body composition reference data from population-based Swedish cohorts. SUBJECTS/METHODS: Four population-based cross-sectional cohort studies including 1424 adult Swedes were divided into five age groups (20-29, 30-39, 40-49, 50-61 and 75 years of age); BMI 24.6±3.9 kg/m(2) were pooled. Body composition was measured with DXA. RESULTS: The difference in BMI from the youngest to the oldest age group was 3.2 and 4.3 kg/m(2) in men and women, respectively (P<0.001, both sexes), and fat mass (FM) was 9.9 and 9.1% higher in the oldest compared with the youngest men and women (P<0.001, both sexes). Fat-free mass (FFM) remained stable up to 60 years of age in men (P=0.83) and was lower at 75 years of age compared with the younger ages. In women, FFM was lower from age 60. From youngest to oldest age groups, height-adjusted FM differed from 4.6 to 7.8 kg/m(2) in men and from 6.8 to 10.8 kg/m(2) in women (P<0.001, both sexes). CONCLUSIONS: Our results provide reference data on body composition in Swedish populations. BMI and FM were higher among older age groups compared with the younger ones. FFM remained stable up to 60 years of age and was lower first among the 75 years of age.


Subject(s)
Adiposity , Aging , Bone Development , Muscle Development , Obesity/epidemiology , Overweight/epidemiology , Absorptiometry, Photon , Adiposity/ethnology , Adult , Aged , Body Composition , Body Height/ethnology , Body Mass Index , Cohort Studies , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Obesity/ethnology , Overweight/ethnology , Prevalence , Sex Factors , Sweden/epidemiology , Whole Body Imaging , Young Adult
3.
Oecologia ; 171(2): 357-65, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22968292

ABSTRACT

A key challenge in the estimation of tropical arthropod species richness is the appropriate management of the large uncertainties associated with any model. Such uncertainties had largely been ignored until recently, when we attempted to account for uncertainty associated with model variables, using Monte Carlo analysis. This model is restricted by various assumptions. Here, we use a technique known as probability bounds analysis to assess the influence of assumptions about (1) distributional form and (2) dependencies between variables, and to construct probability bounds around the original model prediction distribution. The original Monte Carlo model yielded a median estimate of 6.1 million species, with a 90 % confidence interval of [3.6, 11.4]. Here we found that the probability bounds (p-bounds) surrounding this cumulative distribution were very broad, owing to uncertainties in distributional form and dependencies between variables. Replacing the implicit assumption of pure statistical independence between variables in the model with no dependency assumptions resulted in lower and upper p-bounds at 0.5 cumulative probability (i.e., at the median estimate) of 2.9-12.7 million. From here, replacing probability distributions with probability boxes, which represent classes of distributions, led to even wider bounds (2.4-20.0 million at 0.5 cumulative probability). Even the 100th percentile of the uppermost bound produced (i.e., the absolutely most conservative scenario) did not encompass the well-known hyper-estimate of 30 million species of tropical arthropods. This supports the lower estimates made by several authors over the last two decades.


Subject(s)
Arthropods , Biodiversity , Models, Statistical , Animals , Monte Carlo Method , Tropical Climate
4.
J Anim Ecol ; 79(6): 1193-203, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20673235

ABSTRACT

1. The extent to which plant-herbivore feeding interactions are specialized is key to understand the processes maintaining the diversity of both tropical forest plants and their insect herbivores. However, studies documenting the full complexity of tropical plant-herbivore food webs are lacking. 2. We describe a complex, species-rich plant-herbivore food web for lowland rain forest in Papua New Guinea, resolving 6818 feeding links between 224 plant species and 1490 herbivore species drawn from 11 distinct feeding guilds. By standardizing sampling intensity and the phylogenetic diversity of focal plants, we are able to make the first rigorous and unbiased comparisons of specificity patterns across feeding guilds. 3. Specificity was highly variable among guilds, spanning almost the full range of theoretically possible values from extreme trophic generalization to monophagy. 4. We identify guilds of herbivores that are most likely to influence the composition of tropical forest vegetation through density-dependent herbivory or apparent competition. 5. We calculate that 251 herbivore species (48 of them unique) are associated with each rain forest tree species in our study site so that the ∼200 tree species coexisting in the lowland rain forest community are involved in ∼50,000 trophic interactions with ∼9600 herbivore species of insects. This is the first estimate of total herbivore and interaction number in a rain forest plant-herbivore food web. 6. A comprehensive classification of insect herbivores into 24 guilds is proposed, providing a framework for comparative analyses across ecosystems and geographical regions.


Subject(s)
Feeding Behavior/physiology , Food Chain , Insecta/classification , Insecta/physiology , Plants/classification , Trees , Animals , Biodiversity , Papua New Guinea , Tropical Climate
5.
Am Nat ; 176(1): 90-5, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20455708

ABSTRACT

There is a bewildering range of estimates for the number of arthropods on Earth. Several measures are based on extrapolation from species specialized to tropical rain forest, each using specific assumptions and justifications. These approaches have not provided any sound measure of uncertainty associated with richness estimates. We present two models that account for parameter uncertainty by replacing point estimates with probability distributions. The models predict medians of 3.7 million and 2.5 million tropical arthropod species globally, with 90% confidence intervals of [2.0, 7.4] million and [1.1, 5.4] million, respectively. Estimates of 30 million or greater are predicted to have <0.00001 probability. Sensitivity analyses identified uncertainty in the proportion of canopy arthropod species that are beetles as the most influential parameter, although uncertainties associated with three other parameters were also important. Using the median estimates suggests that in spite of 250 years of taxonomy and around 855,000 species of arthropods already described, approximately 70% await description.


Subject(s)
Arthropods/physiology , Biodiversity , Models, Theoretical , Uncertainty , Animals , Probability , Sensitivity and Specificity , Tropical Climate
6.
Acta Paediatr ; 97(12): 1691-7, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18795912

ABSTRACT

OBJECTIVE: To assess variables of body composition and identify their correlates in a group of individuals studied from adolescence to early adulthood. METHODS: Cross-sectional results were obtained from 203, 149 and 106 subjects at the respective ages. Sixty-two subjects examined at all three ages constituted the longitudinal study group. A cohort of randomly selected 15-year-old adolescents from an industrial town in Sweden was studied by dual energy X-ray absorptiometry (DXA) and followed up at 17 and 20.5 years. Lean body mass (LBM), fat mass (FM) and total body bone mineral content (TBMC) were measured by DXA. Total bone mineral density (TBMD) was calculated. Information of parental educational level, energy intake and food habits, energy expenditure (TEE) and physical activity level (PAL) was obtained by questionnaires and diaries. RESULTS: LBM, TBMC and TBMD increased significantly more in males and FM more in females, from 15 to 20.5 years of age. Body weight, height, TEE, PAL and the fathers' educational level and, at age 15, also gender were identified as significant correlates of the body composition variables. CONCLUSION: New reference values for body composition at ages 15, 17 and 20.5 years are presented and also a finding about an association between the father's educational level and the adolescent's body composition.


Subject(s)
Body Composition , Absorptiometry, Photon , Adolescent , Bone Density , Cohort Studies , Cross-Sectional Studies , Educational Status , Energy Intake , Energy Metabolism , Female , Humans , Male , Parents , Reference Values , Sex Factors , Surveys and Questionnaires , Sweden , Young Adult
7.
Eur J Clin Nutr ; 59(11): 1324-34, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16091767

ABSTRACT

OBJECTIVE: To assess physical activity and energy expenditure and to identify their correlates during adolescence and early adulthood. DESIGN: In a cohort study, total energy expenditure (TEE) and physical activity level (PAL) were assessed at 15 and 21 y from a 7-day activity diary and predicted BMR. The influences on TEE and PAL of body size, gender, sexual maturity, physical activity habits, sitting time, region, social conditions, employment, food habits, smoking and alcohol intake were examined in multivariate analyses. SUBJECTS: 71 male and 89 female subjects, living in two socioeconomically different regions of Sweden, a university region and an industrial region. SETTING: The university city of Uppsala and the industrial town of Trollhättan. RESULTS: At both 15 and 21 y, PAL and TEE were high, with gender, sitting time and physical activity habits as main correlates. At age 21 y, employment and the mother's educational level also appeared as significant correlates. The relations between the main variables and their correlates were more complex than at age 15 y, and the sitting time was reduced and the activity habits were changed. CONCLUSIONS: A reduction of daily sitting appears to be a major reason why high levels of physical activity and energy expenditure were maintained from 15 to 21 y of age in spite of changed and less frequent activity habits during this interval.


Subject(s)
Energy Metabolism/physiology , Motor Activity/physiology , Adolescent , Adult , Age Factors , Body Height/physiology , Body Mass Index , Body Weight/physiology , Cohort Studies , Educational Status , Female , Humans , Longitudinal Studies , Male , Parents , Reference Values , Sex Factors , Socioeconomic Factors , Sweden , Time Factors
8.
Environ Res ; 98(2): 215-23, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15820728

ABSTRACT

Food is the main source of trace elements for the general population. The gastrointestinal absorption of certain trace elements, e.g., cadmium, is strongly influenced by iron (Fe) status. This factor may also be relevant for the bioavailability of other trace elements. Therefore, we investigated relationships between Fe status indicators and trace element concentrations in blood and serum of 234 boys and girls at ages 15 and 17 years. Fe status was measured using serum ferritin (S-Ft), soluble transferrin receptor in serum (sTfR), and the ratio sTfR/S-Ft. The trace elements we investigated were, in blood, cadmium, cobalt, copper, zinc, selenium, rubidium, mercury, and lead, and, in serum, cobalt, copper, zinc, selenium, rubidium, tungsten, mercury, and lead. We found inverse correlations between Fe status and blood cadmium, blood or serum cobalt, or blood copper. There were positive correlations between Fe status and mercury concentrations. Selenium was positively correlated with sTfR. The relationships between Fe status and lead were equivocal. There were fewer correlations for serum than for blood, but the inverse relationships between Fe status and cobalt were equally strong in serum and blood. We found only occasional, and perhaps spurious, correlations with zinc, rubidium, and tungsten. In conclusion, previous indications that cadmium, cobalt, and copper are absorbed by transport mechanisms similar to that of Fe are supported by this study. Strong positive correlations between Fe status and mercury concentrations remain to be explained.


Subject(s)
Ferritins/blood , Iron/metabolism , Receptors, Transferrin/blood , Trace Elements/blood , Adolescent , Biological Availability , Female , Humans , Male , Mass Spectrometry
9.
Acta Paediatr ; 93(7): 911-21, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15303806

ABSTRACT

AIM: To follow two children with isolated glycerol kinase deficiency (GKD) with severe symptoms into adulthood. METHODS: The patients were followed during approximately 20 y and interviewed about symptoms, diet and physical activity. Fasting provocations, bicycle ergometer tests, dietary registrations, enzyme and mutation analysis were performed by standard protocols. RESULTS: The activity of glycerol kinase (GK) in fibroblasts was <10% of reference. One case had a deletion of exon 17, the other a mutation in exon 7 of the GK gene (601 A-->G). Both mothers were heterozygotes. Two maternal male cousins in one of the families were hemizygotes without symptoms. Tests performed in childhood documented pronounced sensitivity to fasting and physical exercise, whereas such tests at 23 and 31 y of age were essentially normal but with pronounced ketonaemia. After puberty, the boys had no hypoglycaemic symptoms and now report no problems with their condition; thus, their phenotype has changed over time. CONCLUSION: The greater importance of glycerol as a gluconeogenetic substrate in children than in adults may explain the episodes in young patients with GKD, often elicited by catabolic stress. With meals at frequent intervals, access to glucose and avoidance of strenuous sports, the prognosis is good for a normal adult life of a young child with isolated GKD and symptoms of hypoglycaemia.


Subject(s)
Glycerol Kinase/deficiency , Glycerol/urine , Mutation , Acetoacetates/urine , Adult , Child , Child, Preschool , Exons/genetics , Female , Follow-Up Studies , Genotype , Glycerol/blood , Glycerol Kinase/genetics , Glycerol Kinase/metabolism , Heterozygote , Humans , Male , Pedigree , Phenotype , Prognosis
10.
Scand J Med Sci Sports ; 14(1): 24-9, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14723784

ABSTRACT

BACKGROUND: Osteoporosis is a growing health problem. One of the proposed reasons for this is a more sedentary lifestyle. The aim of this study was to investigate the associations between muscle strength and total body bone mineral density (TBMD) in young adults at expected peak bone mass. METHODS: Sixty-four women and 61 men (total 125) 21 years of age were included. Handgrip strength, isokinetic knee-flexion and -extension muscle strength, TBMD, and body composition were measured. RESULTS: Univariate regression analyses showed that knee flexion and extension explained almost 30% of the variation in TBMD in women, whereas handgrip strength was not associated with TBMD. In men, no correlation between any measures of muscle strength and TBMD was evident. Stepwise regression analysis showed that knee-flexion and -extension muscle strength in women were associated with TBMD, R2=0.27. In men, lean body mass, fat mass, weight, and height were predictors for TBMD, R2=0.43, whereas muscle strength did not affect the prediction of TBMD. CONCLUSIONS: Muscle strength at weight-bearing sites is related to TBMD in women, whereas body composition is related to TBMD in men. The association of lower limb strength on TBMD only in young women indicates a gender difference.


Subject(s)
Aging/physiology , Bone Density/physiology , Muscle, Skeletal/physiology , Adolescent , Adult , Age Factors , Body Composition/physiology , Female , Hand/physiology , Humans , Knee/physiology , Life Style , Male , Regression Analysis , Sex Factors , Sweden
11.
Acta Paediatr ; 92(1): 5-11, 2003.
Article in English | MEDLINE | ID: mdl-12650291

ABSTRACT

AIM: As part of a longitudinal nutrition study of adolescents, changes in serum ferritin (s-Ft), serum transferrin receptors (s-TfR) and the TfR/Ft ratio from 15 to 21 y of age were studied in randomly selected Swedish adolescents. METHODS: Blood samples from 60 males and 66 females were drawn at 15, 17 and 21 y of age. RESULTS: In males, median s-Ft increased significantly from 33 microg l(-1) at 15 y to 96 microg l(-1) at 21 y, and in females, after a non-significant decrease at 17 y, from 27 at 15 y to 34 microg l(-1) at 21 y. Between 15 and 17 y, s-TfR increased significantly, in males from 5.9 to 7.7 microg l(-1), and in females from 5.2 to 7.6 microg l(-1), whereas s-TfR decreased significantly in both genders between 17 and 21 y. The log (TfR/Ft) ratio did not change in males between 15 and 17 y, but decreased significantly from 2.2 +/- 0.3 to 1.8 +/- 0.3 by the age of 21 y. In females, the TfR/Ft ratio increased significantly between 15 and 17 y, whereas a significant decrease was found by the age of 21 y. S-Ft <12 microg l(-1) at 15, 17 and 21 y was 3, 2 and 2% in males, and in females 18, 26 and 21%, respectively. CONCLUSION: This study shows an increase in s-Ft and a decline in s-TfR in males, indicating increased iron stores. In females, s-Ft did not increase significantly, whereas s-TfR and the TfR/Ft ratio decreased between 17 and 21 y, indicating that cellular iron needs were met.


Subject(s)
Iron-Binding Proteins/blood , Nutrition Surveys , Puberty/physiology , Receptors, Cell Surface/blood , Receptors, Transferrin/blood , Adolescent , Adult , Anthropometry , Catchment Area, Health , Cohort Studies , Female , Follow-Up Studies , Health Status , Humans , Male , Population Surveillance , Puberty/blood , Radioimmunoassay , Sweden
12.
Acta Paediatr ; 91(10): 1031-8, 2002.
Article in English | MEDLINE | ID: mdl-12434886

ABSTRACT

AIM: To provide reference data for bone mineral variables in 15- and 17-y-old adolescents and to analyse the relationships between these variables and measures of bone and body size, gender, puberty, growth, various lifestyle and environmental factors and socioeconomic background. METHODS: In the same 321 randomly selected adolescents (147 boys and 174 girls) living in two different regions of Sweden, the total bone mineral content (TBMC), bone area (BA) and total bone mineral density (TBMD) were assessed by dual-energy X-ray absorptiometry at ages 15 and 17 y. The effects of bone and body size, gender, growth, sexual maturity, physical activity, region of domicile, social conditions, food habits, smoking and alcohol intake on TBMC and TBMD were examined in multivariate analyses. RESULTS: In the 15-y-old adolescents, BA, height, gender, physical activity, maturity and weight explained 91% and 48%, of the variance in TBMC and TBMD, respectively. In similar analyses in the 17-y-olds, the corresponding figures were 92% and 62%, respectively, when BA, height, growth, physical activity, gender and region emerged as significant in the model. In all these analyses, BA explained most of the variance in TBMC and TBMD. No significant reduction of variance was found when different measures of social conditions, smoking, food habits, alcohol or dietary intakes of energy, calcium or vitamin D were included in the models. The reason why region of domicile had a significant impact on TBMC in the 17-y-olds is not known. The fact that the normal fluoride concentration in drinking water (1.1 mg/L) is 10 times higher in the region where TBMC was higher than in the other region is an interesting observation. CONCLUSION: Almost 90% of the variance in TBMC and 50% of that in TBMD was explained by measures of bone and body size and only a few percent by gender, physical activity, Tanner stage, growth and region of domicile.


Subject(s)
Bone Density , Adolescent , Anthropometry , Female , Humans , Logistic Models , Longitudinal Studies , Male , Puberty , Reference Values , Regression Analysis , Smoking , Socioeconomic Factors , Sweden
13.
Eur J Clin Nutr ; 56(6): 532-8, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12032653

ABSTRACT

OBJECTIVE: To investigate the change in food habits in Swedish adolescents between 15 and 21 y of age with reference to age, sex, region and socioeconomic background. DESIGN: A longitudinal study from 1993 to 1999. SETTING: Two different regions in Sweden, the university city of Uppsala and the industrial town of Trollhättan. SUBJECTS: On three different occasions, 1993, 1995 and 1999, 208 adolescents, 96 males and 112 females, were studied. METHODS: A food frequency questionnaire containing 29 different food groups was used. The questionnaire also contained questions about food habits and amounts of some food items and socioeconomic conditions of the participants and their families. RESULTS: At 17 and 21 y of age, the adolescents consumed significantly more often pasta, vegetables, coffee and tea compared to age 15, while the frequency consumption of fat spread, milk, bread, potatoes, carrots and buns and biscuits decreased. The changes between 15 and 17 were smaller than between age 17 and 21. At age 21, the males decreased their intake of fruit, while the females decreased their intake of meat. No-meat consumers among females increased from 2 to 13%. Higher educational level of the mothers of the adolescents was associated with more frequent consumption of vegetables and pasta between ages 17 and 21. Milk consumption decreased significantly in both sexes. Breakfast habits did not change: 90% had breakfast five times/week or more. CONCLUSIONS: Food habits change significantly during adolescence along with lifestyle changes. Therefore, health promotion during adolescence ought to be more supported by the society.


Subject(s)
Diet/trends , Feeding Behavior , Adolescent , Adult , Age Factors , Anthropometry , Diet Surveys , Educational Status , Female , Food Preferences , Humans , Longitudinal Studies , Male , Sex Factors , Socioeconomic Factors , Surveys and Questionnaires , Sweden
14.
Mar Pollut Bull ; 42(9): 733-41, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11585065

ABSTRACT

The polychaetes of the tidal flats near the town of Iqaluit, Baffin Island were analysed along gradients of environmental disturbance resulting from human activity. Sources of environmental disturbance include a sewage lagoon, garbage sites; and an area of the tidal flat that is cleared by bulldozer. Sampling of the tidal flats included 300 biological sediment cores taken from 75 sites along seven transects. Environmental disturbance has resulted in four zones of polychaete communities with increasing distance. The heavily disturbed zone is closest to the disturbances and is devoid of polychaetes. The disturbed zone follows and is characterized by low diversity the result of increased densities of a few opportunistic species such as, Capitella 'capitata' sp. The moderately disturbed zone is characterized by increased species diversity due to organic enrichment from the disturbances. The undisturbed zone, located the furthest from the sources of disturbance, is characterized by moderate levels of diversity compared to the other three zones.


Subject(s)
Environmental Monitoring/methods , Geologic Sediments/analysis , Polychaeta/growth & development , Water Pollution/analysis , Animals , Ecosystem , Nunavut
15.
Radiat Prot Dosimetry ; 93(3): 197-205, 2001.
Article in English | MEDLINE | ID: mdl-11548345

ABSTRACT

The microdosimetric variance-covariance method has been used for cosmic radiation measurements on-board aircraft. Two independent methods of data analysis are presented; the first based on a high energy neutron calibration and the second on identification of single high LET events in the measured multiple event spectrum. Reduced dose levels at high geomagnetic latitudes are observed on one flight in a period of enhanced solar activity as indicated by a reduced ground-level neutron fluence rate. It is shown that with a reduced 137Cs-calibration factor, a Geiger-Mueller tube can be used as a low LET monitor, and that the wall thickness of a tissue-equivalent proportional counter is not crucial for flight measurements. No covariance is observed on any flight indicating it is sufficient to base dose determinations on variance measurements with only one detector. The uncertainties involved are also discussed in some detail.


Subject(s)
Aircraft , Cosmic Radiation , Radiometry/methods , Altitude , Fast Neutrons , Linear Energy Transfer , Radiation Dosage
16.
Radiat Prot Dosimetry ; 94(3): 227-32, 2001.
Article in English | MEDLINE | ID: mdl-11487805

ABSTRACT

Measurements with a tissue-equivalent proportional counter (TEPC) using the variance-covariance method have been performed in neutron beams between 71 keV and 180 MeV and in the cosmic radiation reference field (CERF) at CERN. The results show that with appropriate linear QD(yD) relations, the ambient dose equivalent can be determined within about 55% in these beams. Build-up measurements show that wall thickness is not crucial for H* determinations at 60 and 180 MeV.


Subject(s)
Models, Theoretical , Neutrons , Radiometry/instrumentation , Brachytherapy/instrumentation , Dose-Response Relationship, Radiation , Equipment Design , Humans , Radiation Dosage , Radiometry/methods , Sensitivity and Specificity
17.
Br J Nutr ; 85(3): 333-41, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11299079

ABSTRACT

The objective of the present study was to describe the intake of dietary fatty acids among healthy 15-year-old boys and girls and to relate the intake of specific fatty acids and the fatty acid composition of the serum cholesterol esters to serum lipid, apolipoprotein (Apo) and insulin concentrations respectively. Fifty-two girls and forty-two boys were randomly selected from the official population register. Unexpectedly, significant inverse associations were found between the dietary content of saturated fatty acids with a chain length of four to fifteen C atoms, mainly derived from milk fat, as well as the corresponding fatty acids in the serum cholesterol esters, on the one hand and the serum concentrations of cholesterol and ApoB on the other. The estimated dietary intake of 4:0-10:0, 12:0 and 14:0 respectively, were all significantly inversely related to the serum cholesterol (r -0.32, r -0.31, r -0.30, all and ApoB (r -0.42, r -0.42, and r -0.40, all concentrations in girls and 12:0 to the ApoB concentration (r -0.55, in boys. The proportions of 12:0 and 15:0 in the serum cholesterol esters were negatively correlated with the serum cholesterol concentrations in both girls (r -0.34, r -0.32, and boys (r -0.53, r -0.32, and with the ApoB concentrations among boys (r -0.61, r -0.43, It is conceivable that milk fat contains or is associated with some component in the diet, or some other characteristics of the food intake, which counterbalances the expected positive relationships between saturated fat intake and lipid levels.


Subject(s)
Adolescent Nutritional Physiological Phenomena , Cholesterol Esters/blood , Dietary Fats/administration & dosage , Fatty Acids/administration & dosage , Adolescent , Animals , Apolipoproteins/blood , Cholesterol Esters/chemistry , Energy Intake , Female , Humans , Insulin/blood , Lipids/blood , Male , Milk , Sex Factors
18.
Acta Paediatr ; 89(10): 1162-8, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11083369

ABSTRACT

UNLABELLED: Serum ferritin and serum transferrin receptor concentrations, growth and food habits were studied in healthy Swedish boys (n = 103) and girls (n = 124) at the age of 17 y and compared with those in the same adolescents at age 15. Between these ages, serum transferrin receptor increased significantly in both boys and girls. Serum ferritin increased significantly in boys but not in girls. The transferrin receptor/ferritin ratio increased significantly in girls but not in boys, indicating insufficient iron stores in the 17-y-old girls in relation to erythropoiesis and iron needs. Between 15 and 17 y the boys' frequency of consumption of milk and bread decreased, while they more often consumed pasta, cheese and coffee. The girls decreased their frequency intake of fat products, milk and meat. The frequency of meat consumption emerged as the single significant predictor for serum ferritin <12 microg/L in girls, but not in boys. The median daily iron intake, determined in a subsample, decreased in boys from 18.7 to 13.6 mg and in girls from 14.1 to 8.8 mg, and the decrease was to a large extent due to cessation of iron fortification of flour. CONCLUSIONS: The results indicate insufficient iron stores in the 17-y-old girls in relation to erythropoiesis and iron needs, but more favourable iron stores in the boys. The absence of a significant decrease in mean serum ferritin despite rapid growth suggests that the earlier iron fortification of flour only marginally contributed to the iron status of Swedish adolescents of this age group.


Subject(s)
Feeding Behavior , Ferritins/blood , Iron Deficiencies , Iron, Dietary/administration & dosage , Receptors, Transferrin/blood , Adolescent , Age Factors , Female , Follow-Up Studies , Food, Fortified , Humans , Iron/blood , Male , Reference Values , Sex Factors , Sweden
19.
Eur J Clin Nutr ; 54 Suppl 1: S21-8, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10805034

ABSTRACT

OBJECTIVE: To give an overview of the dietary habits among adolescents in the Nordic countries and to present results from studies showing the relationship between dietary habits and other lifestyle factors, nutritional status and socio-economic conditions. DESIGN: A number of nutritional studies among adolescents performed during recent decades using recalls, dietary records and food frequency questionnaire. SETTING: Denmark, Finland, Norway and Sweden. SUBJECTS: Adolescents aged 13-18 y. RESULTS: Food habits are characterized by an irregular meal pattern; many adolescents skip breakfast and also the school lunch, whereas most of them have dinner. However, snacking and light meals are very common, contributing 25-35% of the daily energy intake. Smoking is linked to their dietary habits as well as socio-economic conditions. Dietary intakes of vitamins and minerals are adequate for normal health and growth. Dietary calcium intake is high, whereas the intake of fibre, vitamin D, zinc and selenium and, in girls, iron is below the Nordic recommendations. Relatively low prevalence figures of iron deficiency were found. Many studies show a decrease over time in physical activity. The time spent in sedentary activities, such as television and video watching and computer games has increased during recent decades. CONCLUSION: Overweight and obesity are becoming more prevalent in all the Nordic countries, even though the prevalence figures are far below those in the USA. On the other hand, dieting girls are common, which might be a factor behind their irregular meal pattern and food choice. In a perspective, overweight and diseases attributable to obesity will be an immense challenge in the coming decades for both the individuals and the society as well.


Subject(s)
Adolescent Nutritional Physiological Phenomena , Feeding Behavior , Nutritional Status , Adolescent , Diet Surveys , Energy Intake , Exercise , Female , Humans , Male , Obesity/epidemiology , Prevalence , Scandinavian and Nordic Countries/epidemiology
20.
Int J Obes Relat Metab Disord ; 23(7): 764-70, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10454112

ABSTRACT

OBJECTIVE: To compare bone mineral and body composition results of two dual-energy X-ray absorptiometry (DXA) instruments from the same manufacturer. SETTINGS: The Medical departments of Sahlgrenska University Hospital, Göteborg and University Hospital, Uppsala, Sweden. DESIGN: Unique aluminium spine phantoms (Phant A and B) delivered with each DXA machine (DXA-A and DXA-B) were cross-checked on the other machine by using the 'AP spine mode'. Eight adolescents were examined on both instruments within 5 h to ascertain total body variables by using standard, as well as extended, modes of analysis. All these double-examinations were undertaken on two occasions, before and after exchange of a detector on the DXA-B. SUBJECTS: Four males and four females aged 15.4-19.2 y with normal body weights, were examined on both occasions. On each occasion, the first examination was performed in Göteborg on four individuals and in Uppsala on four individuals. RESULTS: On the first occasion the phantom measurements resulted in much lower bone mineral density (BMD) values on the DXA-B than on the DXA-A. Later it was detected that a so-called R-value and the corresponding '%-fat' value were out of range on the DXA-B. After exchange of detector, the difference in phantom BMD-values between the two machines had diminished. On the first occasion in vivo BMD values were lowest on the DXA-B (P < 0.01), while on the second occasion they were significantly lower on the DXA-A (P < 0.05). Soft tissue differences were greater after detector exchange and as compared to DXA-A, DXA-B underestimated body fat by 3.5 kg (13.2 vs 9.7 kg, P < 0.001) and overestimated lean tissue mass by 3.8 kg (47.1 vs 50.9 kg, P < 0.001) on the second occasion. CONCLUSIONS: The differences in results between two apparently identical Lunar DPX-L machines were not acceptable. In multicenter studies, it may be necessary to standardise results of participating machines into results of one machine by means of regression equations obtained by examining subsamples of individuals on one master machine and other participating instruments.


Subject(s)
Absorptiometry, Photon , Body Composition , Bone Density , Absorptiometry, Photon/instrumentation , Adolescent , Adult , Female , Humans , Male , Reproducibility of Results
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