Latent ion tracks were finally observed in diamond.

Injecting high-energy heavy ions in the electronic stopping regime into solids can create cylindrical damage zones called latent ion tracks. Although these tracks form in many materials, none have ever been observed in diamond, even when irradiated with high-energy GeV uranium ions. Here we report the first observation of ion track formation in diamond irradiated with 2-9 MeV C60 fullerene ions. Depending on the ion energy, the mean track length (diameter) changed from 17 (3.2) nm to 52 (7.1) nm. High resolution scanning transmission electron microscopy (HR-STEM) indicated the amorphization in the tracks, in which π-bonding signal from graphite was detected by the electron energy loss spectroscopy (EELS). Since the melting transition is not induced in diamond at atmospheric pressure, conventional inelastic thermal spike calculations cannot be applied. Two-temperature molecular dynamics simulations succeeded in the reproduction of both the track formation under MeV C60 irradiations and the no-track formation under GeV monoatomic ion irradiations.

Genetic analyses of metabolic body weight, carcass weight and body conformation traits in Nordic dairy cattle.

Improving feed efficiency in dairy cattle by animal breeding has started in the Nordic countries. One of the two traits included in the applied Saved feed index is called maintenance and it is based on the breeding values for metabolic BW (MBW). However, BW recording based on heart girth measurements is decreasing and recording based on scales is increasing only slowly, which may weaken the maintenance index in future. Therefore, the benefit of including correlated traits, like carcass weight and conformation traits, is of interest. In this study, we estimated genetic variation and genetic correlations for eight traits describing the energy requirement for maintenance in dairy cattle including: first, second and third parity MBW based on heart girth measurements, carcass weight (CARW) and predicted MBW (pMBW) based on predicted slaughter weight, and first parity conformation traits stature (ST), chest width (CW) and body depth (BD). The data consisted of 21329 records from Finnish Ayrshire and 9780 records from Holstein cows. Heritability estimates were 0.44, 0.53, 0.56, 0.52, 0.54, 0.60, 0.17 and 0.26 for MBW1, MBW2, MBW3, CARW, pMBW, ST, CW and BD, respectively. Estimated genetic correlations among MBW traits were strong (>0.95). Genetic correlations between slaughter traits (CARW and pMBW) and MBW traits were higher (from 0.77 to 0.90) than between conformation and MBW traits (from 0.47 to 0.70). Our results suggest that including information on carcass weight and body conformation as correlated traits into the maintenance index is beneficial when direct BW measurements are not available or are difficult or expensive to obtain.

Genetic correlations between energy status indicator traits and female fertility in primiparous Nordic Red Dairy cattle.

Inclusion of feed efficiency traits into the dairy cattle breeding programmes will require considering early lactation energy status to avoid deterioration in health and fertility of dairy cows. In this regard, energy status indicator (ESI) traits, for example, blood metabolites or milk fatty acids (FAs), are of interest. These indicators can be predicted from routine milk samples by mid-IR reflectance spectroscopy (MIR). In this study, we estimated genetic variation in ESI traits and their genetic correlation with female fertility in early lactation. The data consisted of 37 424 primiparous Nordic Red Dairy cows with milk test-day records between 8 and 91 days in milk (DIM). Routine test-day milk samples were analysed by MIR using previously developed calibration equations for blood plasma non-esterified FA (NEFA), milk FAs, milk beta-hydroxybutyrate (BHB) and milk acetone concentrations. Six ESI traits were considered and included: plasma NEFA concentration (mmol/l) either predicted by multiple linear regression including DIM, milk fat to protein ratio (FPR) and FAs C10:0, C14:0, C18:1 cis-9, C14:0 * C18:1 cis-9 (NEFAFA) or directly from milk MIR spectra (NEFAMIR), C18:1 cis-9 (g/100 ml milk), FPR, BHB (mmol/l milk) and acetone (mmol/l milk). The interval from calving to first insemination (ICF) was considered as the fertility trait. Data were analysed using linear mixed models. Heritability estimates varied during the first three lactation months from 0.13 to 0.19, 0.10 to 0.17, 0.09 to 0.14, 0.07 to 0.10, 0.13 to 0.17 and 0.13 to 0.18 for NEFAMIR, NEFAFA, C18:1 cis-9, FPR, milk BHB and acetone, respectively. Genetic correlations between all ESI traits and ICF were from 0.18 to 0.40 in the first lactation period (8 to 35 DIM), in general somewhat lower (0.03 to 0.43) in the second period (36 to 63 DIM) and decreased clearly (-0.02 to 0.19) in the third period (64 to 91 DIM). Our results indicate that genetic variation in energy status of cows in early lactation can be determined using MIR-predicted indicators. In addition, the markedly lower genetic correlation between ESI traits and fertility in the third lactation month indicated that energy status should be determined from the first test-day milk samples during the first 2 months of lactation.

Atopic asthma after rhinovirus-induced wheezing is associated with DNA methylation change in the SMAD3 gene promoter.

Children with rhinovirus-induced severe early wheezing have an increased risk of developing asthma later in life. The exact molecular mechanisms for this association are still mostly unknown. To identify potential changes in the transcriptional and epigenetic regulation in rhinovirus-associated atopic or nonatopic asthma, we analyzed a cohort of 5-year-old children (n = 45) according to the virus etiology of the first severe wheezing episode at the mean age of 13 months and to 5-year asthma outcome. The development of atopic asthma in children with early rhinovirus-induced wheezing was associated with DNA methylation changes at several genomic sites in chromosomal regions previously linked to asthma. The strongest changes in atopic asthma were detected in the promoter region of SMAD3 gene at chr 15q22.33 and introns of DDO/METTL24 genes at 6q21. These changes were validated to be present also at the average age of 8 years.

Soluble urokinase-type plasminogen activator receptor in patients with suspected infection in the emergency room: a prospective cohort study.

OBJECTIVES: The soluble form of urokinase-type plasminogen activator (suPAR) was evaluated as an early prognostic marker of sepsis in patients with suspected infection. DESIGN: A single-centre prospective cohort study. METHODS: The cohort comprised 539 patients in the emergency department with suspected infection: 59 without systemic inflammatory response syndrome (SIRS) and without bacterial infection (group 1), 68 with bacterial infection and without SIRS (group 2), 54 with SIRS and without bacterial infection (group 3), 309 with sepsis (SIRS and bacterial infection) and without organ failure (group 4) and 49 with severe sepsis (SIRS, bacterial infection and organ failure) (group 5). suPAR was measured on admission using a commercial solid-phase enzyme-linked immunosorbent assay. RESULTS: The median soluble form of the receptor (suPAR) concentrations in groups 1-5 were 4.7, 5.0, 4.4, 4.8 and 7.9 ng mL(-1) , respectively (P < 0.001). The levels were significantly higher in nonsurvivors compared with survivors (8.3 vs. 4.9 ng mL(-1) , P < 0.001) and in patients with severe sepsis (group 5) compared with those in the other groups (7.9 vs. 4.8 ng mL(-1) , P < 0.001). Area under the receiver operating characteristics curve (AUC(ROC) ) for the prediction of case fatality was 0.79 (95% confidence interval [CI]: 0.72-0.86, P < 0.0001) and 0.75 for severe sepsis (95% CI: 0.68-0.81, P < 0.0001). At a cut-off level of 6.4 ng mL(-1) , suPAR had 76% sensitivity and 69% specificity for fatal disease; at a cut-off level of 6.6 ng mL(-1) , the sensitivity and specificity for severe sepsis were 67% and 72%, respectively. In multivariate models, high suPAR remained an independent predictor of case fatality and severe sepsis after adjusting for potential confounders. CONCLUSIONS: A high suPAR level predicts case fatality and severe sepsis in patients with suspected infection.

Bone turnover markers during lactation, postpartum amenorrhea and resumption of menses.

Changes in bone turnover, and consequent bone loss and recovery during lactation and the postweaning period, are likely modulated by varying estrogen levels inherent in these time periods. To address this question we measured serum biochemical markers of bone formation (bone-specific alkaline phosphatase, amino-terminal propeptide of type I procollagen, osteocalcin), of bone resorption (type I collagen carboxy-terminal telopeptide), and serum female sex hormones (estradiol, luteinizing hormone and follicle-stimulating hormone) in 32 healthy mothers prospectively after delivery, 3 months postpartum, after postpartum amenorrhea and 1 year after resumption of menses. During postpartum amenorrhea (mean 5.7, SD 2.9 months) bone mineral density decreased significantly, some 2% at the lumbar spine and some 3% at the femoral neck, but subsequently recovered completely at the former site and partially at the latter. Bone turnover marker levels were elevated at parturition and still at the end of postpartum amenorrhea. Subsequent to parturition the bone resorption marker level showed a decreasing trend while the formation marker levels continued increasing, and eventually coincided with the resorption level within the very first months postpartum. Both lactation and hormonal status modulated bone turnover marker levels. Maternal age was positively associated with increased bone turnover. Interestingly, higher parity and longer history of previous lactation were associated with lower bone turnover marker levels postpartum as compared with previously nulliparous women of the same age. The regression models explained typically some 20-30% of the variability in the bone turnover marker levels. The dynamic pattern in bone turnover is dissimilar to that occurring at menopause and it indicates that the bone loss most likely occurs in the beginning of postpartum period. It also seems that estrogen has a specific influence on bone turnover only during the first months of lactation.

Enterovirus, mycoplasma and other infections as predictors for myocardial infarction.

OBJECTIVES: To study antibodies against five infectious agents for their prediction of major coronary events in men with and without evidence of coronary heart disease at baseline. DESIGN: A case-control study nested within a prospective population study. SUBJECTS: The study cases included 441 men 45-64 years old with nonfatal myocardial infarction or coronary death within a mean follow-up time of 10 years. A total of 165 men had already signs of heart disease at baseline, whilst 276 were apparently healthy at the beginning of the study. Two controls for each case were matched for age, heart disease status and place of residence. Antibodies against enterovirus, Mycoplasma pneumoniae, Chlamydia pneumoniae, cytomegalovirus and adenovirus were determined. RESULTS: Men without reported baseline heart disease, but not those with heart disease, showing the highest quartile of antibodies to enterovirus and mycoplasma or increased levels of immune complex-bound antibodies to chlamydia had a significantly higher risk of coronary events than men with lower level of antibodies. The increased risk demonstrated in men with high levels of antibodies to enterovirus and mycoplasma remained significant after adjustment for other antibodies, acute-phase reactant and conventional risk factors. Serological evidence of infection by multiple agents was also significantly associated with coronary events. CONCLUSIONS: Serological evidence for several infectious agents is associated with the risk of coronary heart disease, but only in men without baseline history of heart disease.

Comparison of eight commercial on-site screening devices for drugs-of-abuse testing.

Eight commercially available on-site drugs-of-abuse testing devices for detecting cannabinoids (THC-COOH), opiates (OPI), cocaine (COC), amphetamines (AMP), metamphetamines (MET) and benzodiazepines (BZO) were evaluated. The used urine specimens suspected of being drug positive were all confirmed by gas chromatographic/mass spectrometry (GC/MS). For AMP and MET, sensitivities varied between 83 and 95% and specificities between 98 and 100%. Correspondingly, sensitivities between 88 and 98% and specificities between 95 and 100% were observed for THC-COOH. For BZO, sensitivities varied between 91 and 97% and specificities between 97 and 100%. Only a few confirmed positive samples were available for OPI and COC, the sensitivities being between 83 and 100% and 100%, respectively. On-site devices did not always find extremely high drug concentrations. False-negative results were found with AMP in particular. Pholcodine, commonly used as medicine, was observed to give false-positive results with most of the devices and was not, however, included in given cross-reactivity tables. It was found that the devices differed markedly with respect to interpretation of test results and to ease of test performance, leading to the suggestion that different criteria for selecting on-site devices for either emergency laboratories in hospitals or for police stations and prisons should be used. Since the overall specificity of any of the devices was not 100% and false positives were identified, we found it important to confirm any positive screening test result.

A 1-year prospective study on the relationship between physical activity, markers of bone metabolism, and bone acquisition in peripubertal girls.

We conducted a 1-yr prospective study to evaluate the association between physical activity and biochemical markers of bone formation and resorption with bone mineral acquisition in 155 peripubertal Caucasian girls (51 gymnasts, 50 runners, and 54 nonathletic controls). The bone mineral density (BMD) of the femoral neck, the greater trochanter, and the lumbar spine were measured by dual energy x-ray absorptiometry. Serum biochemical markers of bone formation (osteocalcin, bone-specific alkaline phosphatase, amino-terminal propeptide of type I procollagen) and bone resorption (degradation product of C-terminal telopeptide of type I collagen) were measured. The 1-yr increase in BMD (adjusted for age, height, Tanner stage, BMD at baseline, and increases in height and weight) of the femoral neck was 0.037 g/cm2 x yr [95% confidence interval (CI), 0.019-0.051 g/cm2 x yr), and that of the greater trochanter was 0.020 g/cm2 x yr (95% CI, 0.003-0.039 g/cm2 x yr) greater in gymnasts than in controls. The corresponding figures for gymnasts compared with runners were 0.038 g/cm2 x yr (95% CI, 0.009-0.041 g/cm2 x yr) and 0.033 g/cm2 x yr (95% CI, 0.006 to 0.043 g/cm2 x yr). The figures for the lumbar spine did not differ significantly between study groups. The baseline serum concentrations of formation markers and resorption marker accounted for 2.3-12.8% (P < 0.05) of the variation in the 1-yr increase in BMD at the femoral neck and lumbar spine. However, there was no significant difference between the levels of adjusted baseline bone turnover markers of the gymnasts, runners, and controls. The present data add considerable support to the argument that high impact mechanical loading is extremely important and beneficial for the acquisition of BMD of the hip during peripubertal years. Our results indicate also that a high rate of bone turnover, reflected as elevated bone markers, is only weakly associated with the 1-yr bone gain in peripubertal girls.

Reduced mildly oxidized LDL in young female athletes.

We investigated the effect of physical activity and sports participation on LDL oxidation in vivo and on lipid risk factors in 183 teenage girls (9-15 years): 64 gymnasts, 61 runners, and 58 controls. Oxidized LDL was measured as baseline levels of conjugated dienes in LDL lipids (ox-LDL). The gymnasts had a 15% lower ratio of LDL conjugated dienes to LDL cholesterol (ox-LDL:LDL ratio, P = 0.0052) compared to controls, and the difference persisted when the body mass index was included as a covariate (ANCOVA, P = 0.013). Also, the gymnasts had a 12% higher ratio of HDL cholesterol to total cholesterol than the controls (ANCOVA, P = 0.046). There were no differences in the other common lipid risk factors between the groups. The ox-LDL:LDL ratio correlated negatively with HDL cholesterol (r = -0.23, P=0.0021) and with physical activity METs (multiples of resting metabolic rate) (r = -0.21, P=0.0040). Our study strengthens the evidence that the atherogenic risk is influenced favourably by physical exercise and sporting activities as early as in adolescents. This risk reduction is associated with lower mildly oxidized LDL in adolescent girls.

Serum albumin and colorectal cancer risk.

OBJECTIVE: To study the relationship between serum albumin and colorectal cancer occurrence. DESIGN: A case-control study nested within a cohort followed from 1968 to 1991. SUBJECTS AND METHODS: The albumin concentration was determined from serum samples stored at -20 degrees C at baseline in 177 incident colorectal cancer cases and 288 controls matched for sex, age and study region. RESULTS: An elevated risk was present of cancer of the left, distal colon at high serum albumin concentrations. No significant association was observed for the right, proximal colon or the rectum. The relative risks of cancer of the distal and proximal colon among individuals in the highest and lowest quartiles of serum albumin were 17.03 (95% confidence interval 1.48-195) and 0.77 (95% confidence interval 0. 19-3.13), respectively. CONCLUSIONS: The present study lends support to the hypothesis that some dietary factor associated with serum albumin may be a risk factor for distal colon cancer.

Low vitamin E status is a potential risk factor for insulin-dependent diabetes mellitus.

OBJECTIVES: To study the association of vitamin E status with occurrence of insulin-dependent diabetes mellitus (IDDM). DESIGN: A case-control study nested within a 21-year follow-up study. SUBJECTS: Nineteen incident IDDM patients with an average age of 28 years and three individually matched controls per patient. MAIN OUTCOME MEASURE: Serum concentrations of alpha-tocopherol. RESULTS: Serum alpha-tocopherol concentration at the baseline examination was inversely associated with IDDM occurring 4-14 years later. The cholesterol-adjusted relative risk of IDDM between the highest and lowest thirds of the vitamin concentration was 0.12 (95% confidence interval = 0.02-0.85). CONCLUSIONS: The finding corroborates the hypothesis of a protective effect of vitamin E against development of IDDM. Because of the relatively old age of the patients in the present population, further epidemiological studies on the topic are warranted.

Serum androgen-anabolic hormones and the risk of rheumatoid arthritis.

OBJECTIVE: It has been hypothesised, mainly on the basis of indirect evidence, that low serum concentrations of androgen-anabolic hormones would play a causal part in the aetiology of rheumatoid arthritis (RA). METHODS: A case-control study was nested with a Finnish cohort of 19,072 adults who had neither arthritis nor a history of it at the baseline examination during 1973-1977. Pre-illness serum specimens for the assay of testosterone and dehydroepiandrosterone sulphate (DHEAS) were available from 116 cases who had developed RA by late 1989. Three controls per each incident case were individually matched for sex, age, and municipality. RESULTS: The mean testosterone concentration was 1.4 nmol/l in those 84 women who developed RA and 1.4 nmol/l in their controls; the corresponding figures for DHEAS were 5.2 mumol/l and 5.5 mumol/l, respectively. Mean testosterone concentration in the 32 male cases was 26.1 nmol/l and 26.4 nmol/l in their controls; the corresponding figures for DHEAS were 11.2 mumol/l and 10.1 mumol/l, respectively. Analysis by subgroups (rheumatoid factor positive and negative disease, pre-menopausal and postmenopausal women) and by hormone distributions showed no differences. CONCLUSION: The findings are not in line with the contention that low concentrations of testosterone and DHEAS play a part in the aetiology of RA.

Trends in serum lipid levels during 1980-1992 in children and young adults. The Cardiovascular Risk in Young Finns Study.

To assess secular trends in serum lipid levels in Finnish children and young adults, the authors examined a total of 3,517, 2,769, 2,392, 352, and 880 subjects who had complete data on serum lipids in 1980, 1983, 1986, 1989, and 1992, respectively, in a longitudinal follow-up study. Trend analyses were carried out among subjects aged 15 (n = 1,835) or 18 (n = 1,562) years to exclude the confounding effect of age on the study variables. Data on obesity, physical activity, smoking, and alcohol use were available from each study year, and data on diet were available for the study years 1980, 1986, and 1992. Between 1980 and 1992, mean total cholesterol levels decreased from 4.88 to 4.47 mmol/liter (from 189 to 173 mg/dl), and low density lipoprotein cholesterol levels decreased from 3.06 to 2.85 mmol/liter (from 119 to 110 mg/dl). The mean high density lipoprotein cholesterol levels decreased by 19%, from 1.43 to 1.15 mmol/liter (55.2 to 44.6 mg/dl). During 1986-1992, triglyceride levels increased by 15%, from 0.88 to 1.01 mmol/liter (78.2 to 89.9 mg/dl). During 1980-1992, body mass index values increased from 20.8 to 21.8 kg/m2, parallel to increases in skinfold thickness. In the diet, the ratio of polyunsaturated to saturated fatty acids increased from 0.26 to 0.39. Alcohol and oral contraceptive use became more frequent, and the subjects tended to become less physically active. In conclusion, a change in the lipid profile in Finnish adolescents aged 15 and 18 years and young adults during 1980-1992 was observed, characterized by a decrease in low density lipoprotein cholesterol and high density lipoprotein cholesterol levels and an increase in triglyceride level. Possible determinants for these changes include alterations in diet and a trend toward increased obesity.

Serum immunoglobulins and the risk of rheumatoid arthritis.

OBJECTIVE: Rheumatoid arthritis (RA) is associated with several autoantibodies that can precede the clinical disease. The immunoglobulin concentrations in serum samples before illness were studied to learn more about the immunological process before RA. METHODS: A case-control study was nested within a Finnish cohort of 19,072 adults who had neither arthritis nor a history of it at the baseline examination during 1973-1977. By late 1989, 124 had developed RA, of which 89 were positive for rheumatoid factor (RF). Three controls per each incident case were individually matched for sex, age, and municipality. The concentrations of IgG, IgA, and IgM were measured from stored serum samples. RESULTS: Serum IgG before illness was found to be directly proportional to the risk of RF positive RA, and a non-linear association was present between serum IgA and the risk of RF positive RA. These associations were constant between men and women and other subgroups of the study population and not confounded by serum orosomucoid concentration, level of education, smoking, alcohol intake or body mass index. As adjusted for these factors, the odds ratios (95% confidence intervals) of RF positive RA in the lowest, mid, and highest tertiles of IgG distribution were 1.00, 1.55 (0.81, 2.97), and 2.22 (1.16, 4.26), and in the tertiles of IgA 1.00, 2.23 (1.14, 4.36), and 1.78 (0.89, 3.57), respectively. The associations persisted throughout the entire observation period but were most distinct when the period to the onset of clinical RA was > or = 10 years. IgM carried no predictive significance. None of the serum immunoglobulins predicted the development of RF negative RA. CONCLUSIONS: Increased IgG levels may reflect some, at present unknown process in the early events leading to the development of RA, typically occurring > or = 10 years before the onset of clinical disease.

Reference intervals for serum thyrotropin, free thyroxine and free triiodothyronine in healthy adults in Finland, measured by an immunoautomate based on time-resolved fluorescence (AutoDELFIA).

We have established reference intervals for healthy adults of serum thyrotropin, free thyroxine and free triiodothyronine using the AutoDELFIA (Wallac, Finland) automatic measuring device. The determination of reference intervals in a proper manner is costly, and many laboratories adopt reference ranges from the literature rather than determining them alone. This is the first report on reference values in thyroidology where this automatic system based on time-resolved fluorescence has been used. The reference intervals for thyrotropin, free thyroxine and free triiodothyronine were 0.6-4.3 mIU/l, 9.6-17.1 pmol/l and 4.3-7.5 pmol/l, respectively.

Tracking of serum lipoprotein (a) concentration and its contribution to serum cholesterol values in children from 7 to 36 months of age in the STRIP Baby Study. Special Turku Coronary Risk Factor Intervention Project for Babies.

We investigated the tracking phenomenon of serum lipoprotein (a) concentrations and assessed the impact of serum concentration of lipoprotein (a) cholesterol on total cholesterol concentrations in children from 7 to 36 months of age. Serum samples for lipoprotein (a) and cholesterol determinations at 7, 13, 24 and 36 months were prospectively obtained from 430 children. Serum lipoprotein (a) was determined using immunoradiometric assay. A strong correlation was observed between lipoprotein (a) concentrations at 7 and 36 months of age (r = 0.88, P < 0.001). Seventy-eight per cent to 86% of the children in the lowest and highest lipoprotein (a) quintiles at 13 months remained in the respective quintiles at 36 months. The average contribution of lipoprotein (a) cholesterol to total cholesterol varied from 0.5% to 3.2% (individual variation 0.13-32.39%) depending on the type of milk received and the age of the children. At 7 months the contribution was 0.44% in breast-fed and 0.93% in formula-fed infants (P < 0.0001). The tracking phenomenon of serum lipoprotein (a) concentrations is strong already in early childhood. The contribution of lipoprotein (a) cholesterol to serum total cholesterol concentration should be taken into account when the changes in serum cholesterol levels are interpreted in the first year of life.

Prospective randomized trial of low-saturated-fat, low-cholesterol diet during the first 3 years of life. The STRIP baby project.

BACKGROUND: The long-term consequences of modified fat intake in early childhood are poorly known. The randomized prospective STRIP baby project evaluates the effects of repeated dietary counseling on nutrient intakes and serum lipid values in children 7 months to 3 years old. METHODS AND RESULTS: One thousand sixty-two infants were randomized to intervention and control groups at 7 months of age. The families of the 540 intervention children were counseled to reduce the child's intake of saturated fat and cholesterol but to ensure adequate energy intake. Five hundred twenty-two control children consumed an unrestricted diet. Food records were kept, and serum lipids were measured at 5- to 12-month intervals. Intakes of saturated fat, fat as proportion of energy (E%), and cholesterol were lower in the intervention children than in control children at 13, 24, and 36 months of age. Fat intake by the intervention children decreased from 29 +/- 5 E% at 8 months of age to 26 +/- 6 E% at 13 months and then increased to 30 +/- 5 E% at 24 months and to 31 +/- 5 E% at 36 months. The control children consumed 29 +/- 4 E%, 28 +/- 5 E%, 33 +/- 5 E%, and 33 +/- 5 E% of fat at 8, 13, 24, and 36 months, respectively. The ratio of dietary poly-unsaturated to saturated fats of the intervention children was consistently higher than that of the control children (P < .0001). Baseline adjusted mean serum cholesterol concentration was lower in the intervention children than control children between 13 and 36 months (P < .0001; 95% confidence interval of the difference between the group means, -0.27 to -0.12 mmol/L). The effect was significant only in boys (95% confidence interval, -0.39 to -0.20 mmol/L in boys; -0.21 to 0.01 mmol/L in girls). CONCLUSIONS: Repeated individualized dietary counseling markedly reduces the increase in serum cholesterol concentration that occurs in control children during the first years of life.