Tumor Subtype-Specific Associations of Hormone-Related Reproductive Factors on Breast Cancer Survival

Purpose

It is inconclusive whether reproductive factors, which are known as risk factors of breast cancer, also influence survival. We investigated overall and subtype-specific associations between reproductive factors and breast cancer survival.

Methods

Among 3,430 incident breast cancer patients who enrolled in the Seoul Breast Cancer Study, 269 patients (7.8%) died and 528 patients (15.4%) recurred. The overall and subtype-specific associations of reproductive factors including age at menarche and menopause, duration of estrogen exposure, menstrual cycle, parity, age at first full-term pregnancy, number of children, age at last birth, time since the last birth, and duration of breastfeeding, on overall and disease-free survival (OS and DFS) were estimated by hazard ratios (HRs) and 95% confidence intervals (95% CIs) using a multivariate Cox proportional hazard model.

Results

An older age at menarche (HR for OS=1.10, 95% CI=1.03-1.19), a greater number of children (≥4 vs. 2, HR for DFS=1.58, 95% CI=1.11-2.26), and a shorter time since last birth (<5 vs. ≥20 years, HR for DFS=1.67, 95% CI=1.07-2.62) were associated with worse survival while longer duration of estrogen exposure with better survival (HR for DFS=0.97, 95% CI=0.96-0.99). In the stratified analyses by subtypes, those associations were more pronounced among women with hormone receptor and human epidermal growth factor 2 positive (HR+ HER2+) tumors.

Conclusions

It is suggested that reproductive factors, specifically age at menarche, number of children, time since last birth, and duration of estrogen exposure, could influence breast tumor progression, especially in the HR+ HER2+ subtype.     

Cigarette smoking and Down syndrome.

A matched case-control study of 100 mothers of Down syndrome children, 100 mothers of children with other defects (defect controls), and 100 mothers of children with no defects (normal controls) was carried out. All infants were born in upstate New York in 1980 and 1981. Matching was very close on maternal age for the normal controls but not for the defect controls. The risk ratios for the association of cigarette smoking around the time of conception with Down syndrome was 0.58 (90% confidence interval of 0.34-0.98) in the case-defect control comparison and 0.56 (90% confidence interval of 0.33-0.95) in the case-normal control comparison. Stratification by alcohol ingestion and maternal age did not abolish the negative trend to association. The results are contrary to that of an earlier study of others that found a positive association of older age and trisomy in spontaneous abortions. In fact, among mothers of Down syndrome cases over age 30 in this analysis, the risk ratio was lower than for younger mothers. (For case-normal control comparisons, the value was 0.39 [90% confidence interval of 0.17-0.87]). If not due to chance or confounding, the negative association in our data may be attributable to, among other factors, a selective effect of smoking upon survival or fertilizability of +21 gametes prior to conception or upon survival of +21 conceptuses after fertilization.     

Search for mutations altering protein charge and/or function in children of atomic bomb survivors: final report.

A sample of (1) children whose parents had been proximally exposed (i.e., less than 2,000 m from the hypocenter) at the time of the atomic bombings of Hiroshima and Nagasaki and (2) a suitable comparison group have been examined for the occurrence of mutations altering the electrophoretic mobility or activity of a series of 30 proteins. The examination of the equivalent of 667,404 locus products in the children of proximally exposed persons yielded three mutations altering electrophoretic mobility; the corresponding figure for the comparison group was three mutations in 466,881 tests. The examination of a subset of 60,529 locus products for loss of enzyme activity in the children of proximally exposed persons yielded one mutation; no mutations were encountered in 61,741 determinations on the children of the comparison group. When these two series are compared, the mutation rate observed in the children of proximally exposed persons is thus 0.60 x 10(-5)/locus/generation, with 95% confidence intervals between 0.2 and 1.5 x 10(-5), and that in the comparison children is 0.64 x 10(-5)/locus/generation, with 95% intervals between 0.1 and 1.9 x 10(-5). The average conjoint gonad doses for the proximally exposed parents are estimated to be 0.437 Gy of gamma radiation and 0.002 Gy of neutron radiation. If a relative biological effectiveness of 20 is assigned to the neutron radiation, the combined total gonad dose for the parents becomes 0.477 Sv. (Organ absorbed doses are expressed in gray [1 Gy = 100 rad]; where dose is a mixture of gamma and neutron radiation, it is necessary because of the differing relative biological effectiveness of gamma and neutron radiation to express the combined gamma-neutron gonad exposures in sieverts [1 Sv = 100 rem]).     

Intra- and Intersession Repeatability of an Optical Quality and Intraocular Scattering Measurement System in Children

Purpose

To evaluate intra- and intersession repeatability of objective optical quality and intraocular scattering measurements with a double-pass system in children.

Methods

Forty-two eyes of 42 children were included in the study. An optical quality analysis system (OQAS) was used to measure optical quality parameters, including modulation transfer function cutoff frequency (MTF_cutoff), Strehl ratio (SR), OQAS values (OV) at 3 different contrasts and objective scatter index (OSI). Three measurement sessions with 10-min intervals were operated by the same technician, and in each session four consecutive measurements were obtained.

Results

Mean values for MTF_cutoff, SR and OSI were 46.85 ± 7.45cpd, 0.27 ± 0.06 and 0.34 ± 0.22 respectively. 1) The intraclass correlation coefficients were ranged from 0.89 to 0.97 and coefficients of variation from 0.06 to 0.16 for all the parameters in the first session; the relative repeatability were 11.1% (MTF_cutoff), 22.5% (SR), 10.9% (OV100%), 16.6% (OV2%), 22.4% (OV9%) and 56.3% (OSI). Similar results were found in the second and third sessions. 2) Bland-Altman analysis showed that narrow 95% confidence intervals (compared between the first and second sessions) ranged from -5.42 to 5.28 (MTF_cutoff), -0.05 to 0.07 (SR), -0.18 to 0.18 (OV100%), -0.26 to 0.29 (OV20%), -0.33 to 0.39 (OV9%) and -0.11 to 0.09 (OSI); the comparison between any two of the three sessions showed similar results.

Conclusion

Measurements of optical quality and intraocular scattering in children by the double-pass system showed good intra- and intersession repeatability. Retinal image quality is high and intraocular scattering is low in children.     

Salivary Melatonin Rhythm as a Marker of the Circadian System in Healthy Children and Those With Attention-Deficit/Hyperactivity Disorder

Attention-deficit/hyperactivity disorder (ADHD) is the most common neurobehavioral disorder of childhood. Problems with sleep structure, efficiency, and timing have been reported in some, but not all, studies on ADHD children. As the sleep-wake cycle belongs to circadian rhythms, the timekeeping circadian system might be involved in ADHD. To assess whether the circadian system of ADHD children differs from that of controls, the rhythm of the pineal hormone melatonin was used as a reliable marker of the system. Saliva from 34 ADHD and 43 control 6- to 12-yr-old children was sampled at 2-h intervals throughout the entire 24-h cycle, and the melatonin profiles of the ADHD and control children were compared. The nocturnal melatonin peaks of the ADHD and control group did not differ significantly. The high nocturnal interindividual variability of the peaks seen in adulthood was present already in the studied children. The 24-h melatonin profiles of all the ADHD subjects did not differ significantly from those of the control subjects. Categorization of subjects according to age, into groups of 6- to 7-yr-old (9 ADHD, 5 control), 8- to 9-yr-old (16 ADHD, 26 control), and 10- to 12-yr-old (9 ADHD, 12 control) children, revealed significant differences between the ADHD and control group in the melatonin rhythm waveform, but not in nocturnal melatonin peaks; the peaks were about the same in both groups and did not change significantly with increasing age. In the oldest, but not in the younger, children, the melatonin signal duration in the ADHD group was shorter than in the control group. The difference might be due to the fact that whereas in the control group both the evening melatonin onset and the morning offset phase delayed in the oldest children relative to those in the youngest children, in the ADHD group only the onset, but not the offset, phase delayed with increasing age. The data may indicate subtle differences between the circadian system of ADHD and control children during development. (Author correspondence: sumova@biomed.cas.cz)     

Plasma C-type natriuretic peptide levels in healthy children

C-type natriuretic peptide (CNP) is assuming increasing importance in cardiovascular disease, and in adults its plasma levels are related to clinical and functional disease severity. Data are scarce regarding the reference values for CNP in infancy. Aim of this study was to assess the reference intervals for CNP in human healthy newborns and infants. Plasma CNP was measured in 121 healthy children divided into: 41 newborns (age 0-3 days), 24 newborns (4-30 days), 22 infants (1-12 months) and 32 children (1-12 years). A group of 32 healthy adult subjects (age 64 ± 1 years) was also studied. CNP was measured by a specific radioimmunoassay. Between- and within-assay variability resulted ≤ 30 and 20%, respectively and analytical sensitivity 0.77 ± 0.05 pg/tube. Plasma CNP resulted significantly higher in children than in adult subjects (13.6 ± 1.2 pg/ml vs. 7.4 ± 1.0 pg/ml, p=0.030). When the results were analyzed as a function of the age the reference intervals for plasma CNP resulted: 11.6 ± 2.1 pg/ml for newborns (0-3 days), 16.4 ± 3.7 pg/ml for newborns (4-30 days), 15.4 ± 2.7 pg/ml for infants (1-12 months), 13.6 ± 2.3 pg/ml for children (1-12 years) [p=0.01 newborns (4-30 days) vs. adults; p=0.03 infants (1-12 months) vs. adults]. CNP showed the highest concentrations after 12h of life with a peak between 4 and 5 days of life and with a progressive decline afterwards. According to these data at least five different reference intervals for CNP determinations should be used. These observations may be helpful for future clinical application of CNP in human children.     

Regional changes in CNS levels of the S-100 and 14-3-2 proteins during development and aging of the mouse

The levels of the S-100 and 14-3-2 proteins were determined in a number of regions of mouse brain at intervals from 1 day to 30 months of age. Both S-100 and 14-3-2 were found in measurable amounts as early as the first day of postnatal age but did not begin to accumulate rapidly in the forebrain, brain stem and cerebellum of the mouse brain until some time between the 7th and 14th days. From days 14 to 28 the levels of S-100 and 14-3-2 in each region continued to increase rapidly with the exception of the forebrain where the rate of accumulation of S-100 appeared to lag considerably behind that in the other regions. The proteins continued to accumulate at a rapid rate until approximately 6 months of age. From 6 to 30 months of age, the levels of 14-3-2 remained relatively stable in cerebellum, hippocampus and hypothalamus and appeared to decrease slightly in striatum and cerebral cortex. In the case of S-100, the level of the protein increased in all regions of brain from 6 to 30 months but the increase was most pronounced in the hippocampus, hypothalamus and striatum. The principal conclusion derived from this study is that the biochemical development and aging of the central nervous system are regionally selective processes.     

Contents of antibodies to Bordetella pertussis antigens in patients with rheumatic diseases

Study of presence of antibodies against pertussis in 72 rheumatic patients (with uvenile rheumatoid arthritis, systemic lupus erythematosus, etc.) aged 1-18 year old without history of pertussis was performed. Mean age of the patients was 10.6 +/- 0.48 year old, duration of illness--51.2 +/- 4.42 months. Immunosupressive therapy at the time of the study was conducted in 68 (94.4%) children. Using ELISA method, IgG to pertussis toxin (PT) and to antigens of acellular pertussis vaccine (aPV) were detected in 98.6% and 100% of children. High titers of antibodies were detected more frequently in 7-18 year old age group, which can indicate recent pertussis disease or infection. Vaccination history was studied in 131 children with rheumatic diseases. Incidence of pertussis in 43 unvaccinated children was 116.3 per 1000, and in 16 children with incomplete vaccination--62.5 per 1000. Out of 75 patients, who received vaccination series and revaccination, clinically distinct pertussis was not diagnosed.     

Emergency health care use and follow-up among sociodemographic groups of children who visit emergency departments for mental health crises

Background:

Previous studies of differences in mental health care associated with children’s sociodemographic status have focused on access to community care. We examined differences associated with visits to the emergency department.

Methods:

We conducted a 6-year population-based cohort analysis using administrative databases of visits (n = 30 656) by children aged less than 18 years (n = 20 956) in Alberta. We measured differences in the number of visits by socioeconomic and First Nations status using directly standardized rates. We examined time to return to the emergency department using a Cox regression model, and we evaluated time to follow-up with a physician by physician type using a competing risks model.

Results:

First Nations children aged 15–17 years had the highest rate of visits for girls (7047 per 100 000 children) and boys (5787 per 100 000 children); children in the same age group from families not receiving government subsidy had the lowest rates (girls: 2155 per 100 000 children; boys: 1323 per 100 000 children). First Nations children (hazard ratio [HR] 1.64; 95% confidence interval [CI] 1.30–2.05), and children from families receiving government subsidies (HR 1.60, 95% CI 1.30–1.98) had a higher risk of return to an emergency department for mental health care than other children. The longest median time to follow-up with a physician was among First Nations children (79 d; 95% CI 60–91 d); this status predicted longer time to a psychiatrist (HR 0.47, 95% CI 0.32–0.70). Age, sex, diagnosis and clinical acuity also explained post-crisis use of health care.

Interpretation:

More visits to the emergency department for mental health crises were made by First Nations children and children from families receiving a subsidy. Sociodemographics predicted risk of return to the emergency department and follow-up care with a physician.Emergency departments are a critical access point for mental health care for children who have been unable to receive care elsewhere or are in crisis.¹ Care provided in an emergency department can stabilize acute problems and facilitate urgent follow-up for symptom management and family support.^1,2Race, ethnic background and socioeconomic status have been linked to a crisis-oriented care patterns among American children.^3,4 Minority children are less likely than white children to have received mental health treatment before an emergency department visit,^3,4 and uninsured children are less likely to receive an urgent mental health evaluation when needed.⁴ Other studies, however, have shown no relation between sociodemographic status and mental health care,^5,6 and it may be that different health system characteristics (e.g., pay-for-service, insurance coverage, publicly funded care) interact with sociodemographic status to influence how mental health resources are used. Canadian studies are largely absent in this discussion, despite a known relation between lower income and poorer mental health status,⁷ nationwide documentation of disparities faced by Aboriginal children,^8–10 and government-commissioned reviews that highlight deficits in universal access to mental health care.¹¹We undertook the current study to examine whether sociodemographic differences exist in the rates of visits to emergency departments for mental health care and in the use of post-crisis health care services for children in Alberta. Knowledge of whether differences exist for children with mental health needs may help identify children who could benefit from earlier intervention to prevent illness destabilization and children who may be disadvantaged in the period after the emergency department visit. We hypothesized that higher rates of emergency department use, lower rates of follow-up physician visits after the initial emergency department visit, and a longer time to physician follow-up would be observed among First Nations children and children from families receiving government social assistance.     

“Upper Limits of Normal” Antistreptolysin O and Antideoxyribonuclease B Titers

"Upper limits of normal" antistreptolysin O (ASO) and antideoxyribonuclease (ADN) B titers were determined on serum specimens from various age groups of pediatric patients with no history of a recent streptococcal infection and on healthy adult hospital employees. The upper limit of normal value is that level of antibody titer exceeded by no more than 15% of the total subjects in each age group. This value varies with the age of the subject, and the most pronounced differences are between the values of preschool age children, school age children, and adults. The upper limit of normal values for these groups were as follows: preschool age, ASO = 85(100); ADN B = 60(50); school age, ASO = 170(166); ADN B=1 70(166); and adult, ASO = 85(100); ADN B = 85(100).     

The effect of birth interval on malnutrition in Bangladeshi infants and young children

This study was undertaken to investigate the independent effect of the length of birth interval on malnutrition in infants, and children aged 6-39 months. Data for this study were drawn from a post-flood survey conducted during October-December 1988 at Sirajganj of the Sirajgani district and at Gopalpur of the Tangail district in Bangladesh. The survey recorded the individual weights of 1887 children. Cross-tabulations and logistic regression procedures were applied to analyse the data. The proportion of children whose weight-for-age was below 70% (moderate-to-severely malnourished) and 60% (severely malnourished) of the NCHS median was tabulated against various durations of previous and subsequent birth intervals. The odds of being moderately or severely malnourished were computed for various birth intervals, controlling for: the number of older surviving siblings; maternal education and age; housing area (a proxy for wealth); age and sex of the index child; and the prevalence of diarrhoea in the previous 2 weeks for the index child. About one-third of infants and young children were moderately malnourished and 15% were severely malnourished. The proportion of children who were under 60% weight-for-age decreased with the increase in the length of the subsequent birth interval, maternal education and housing area. The proportion of malnourished children increased with the number of older surviving children. Children were at higher risk of malnutrition if they were female, their mothers were less educated, they had several siblings, and either previous or subsequent siblings were born within 24 months. This study indicates the potential importance of longer birth intervals in reducing malnutrition in children.     

Increased incidence and clinical picture of childhood narcolepsy following the 2009 H1N1 pandemic vaccination campaign in Finland

Background

Narcolepsy is a rare neurological sleep disorder especially in children who are younger than 10 years. In the beginning of 2010, an exceptionally large number of Finnish children suffered from an abrupt onset of excessive daytime sleepiness (EDS) and cataplexy. Therefore, we carried out a systematic analysis of the incidence of narcolepsy in Finland between the years 2002–2010.

Methods

All Finnish hospitals and sleep clinics were contacted to find out the incidence of narcolepsy in 2010. The national hospital discharge register from 2002 to 2009 was used as a reference.

Findings

Altogether 335 cases (all ages) of narcolepsy were diagnosed in Finland during 2002–2009 giving an annual incidence of 0.79 per 100 000 inhabitants (95% confidence interval 0.62–0.96). The average annual incidence among subjects under 17 years of age was 0.31 (0.12–0.51) per 100 000 inhabitants. In 2010, 54 children under age 17 were diagnosed with narcolepsy (5.3/100 000; 17-fold increase). Among adults ≥20 years of age the incidence rate in 2010 was 0.87/100 000, which equals that in 2002–2009. Thirty-four of the 54 children were HLA-typed, and they were all positive for narcolepsy risk allele DQB1*0602/DRB1*15. 50/54 children had received Pandemrix vaccination 0 to 242 days (median 42) before onset. All 50 had EDS with abnormal multiple sleep latency test (sleep latency <8 min and ≥2 sleep onset REM periods). The symptoms started abruptly. Forty-seven (94%) had cataplexy, which started at the same time or soon after the onset of EDS. Psychiatric symptoms were common. Otherwise the clinical picture was similar to that described in childhood narcolepsy.

Interpretation

A sudden increase in the incidence of abrupt childhood narcolepsy was observed in Finland in 2010. We consider it likely that Pandemrix vaccination contributed, perhaps together with other environmental factors, to this increase in genetically susceptible children.     

Suicide among children and adolescents in Canada: trends and sex differences, 1980�C2008

Background:

Suicide is the second leading cause of death for young Canadians (10–19 years of age) — a disturbing trend that has shown little improvement in recent years. Our objective was to examine suicide trends among Canadian children and adolescents.

Methods:

We conducted a retrospective analysis of standardized suicide rates using Statistics Canada mortality data for the period spanning from 1980 to 2008. We analyzed the data by sex and by suicide method over time for two age groups: 10–14 year olds (children) and 15–19 year olds (adolescents). We quantified annual trends by calculating the average annual percent change (AAPC).

Results:

We found an average annual decrease of 1.0% (95% confidence interval [CI] −1.5 to −0.4) in the suicide rate for children and adolescents, but stratification by age and sex showed significant variation. We saw an increase in suicide by suffocation among female children (AAPC = 8.1%, 95% CI 6.0 to 10.4) and adolescents (AAPC = 8.0%, 95% CI 6.2 to 9.8). In addition, we noted a decrease in suicides involving poisoning and firearms during the study period.

Interpretation:

Our results show that suicide rates in Canada are increasing among female children and adolescents and decreasing among male children and adolescents. Limiting access to lethal means has some potential to mitigate risk. However, suffocation, which has become the predominant method for committing suicide for these age groups, is not amenable to this type of primary prevention.Suicide was ranked as the second leading cause of death among Canadians aged 10–34 years in 2008.¹ It is recognized that suicidal behaviour and ideation is an important public health issue among children and adolescents; disturbingly, suicide is a leading cause of Canadian childhood mortality (i.e., among youths aged 10–19 years).^2,3Between 1980 and 2008, there were substantial improvements in mortality attributable to unintentional injury among 10–19 year olds, with rates decreasing from 37.7 per 100 000 to 10.7 per 100 000; suicide rates, however, showed less improvement, with only a small reduction during the same period (from 6.2 per 100 000 in 1980 to 5.2 per 100 000 in 2008).¹Previous studies that looked at suicides among Canadian adolescents and young adults (i.e., people aged 15–25 years) have reported rates as being generally stable over time, but with a marked increase in suicides by suffocation and a decrease in those involving firearms.² There is limited literature on self-inflicted injuries among children 10–14 years of age in Canada and the United States, but there appears to be a trend toward younger children starting to self-harm.^3,4 Furthermore, the trend of suicide by suffocation moving to younger ages may be partly due to cases of the “choking game” (self-strangulation without intent to cause permanent harm) that have been misclassified as suicides.^5–7Risk factors for suicidal behaviour and ideation in young people include a psychiatric diagnosis (e.g., depression), substance abuse, past suicidal behaviour, family factors and other life stressors (e.g., relationships, bullying) that have complex interactions.⁸ A suicide attempt involves specific intent, plans and availability of lethal means, such as firearms,⁹ elevated structures¹⁰ or substances.¹¹ The existence of “pro-suicide” sites on the Internet and in social media¹² may further increase risk by providing details of various ways to commit suicide, as well as evaluations ranking these methods by effectiveness, amount of pain involved and length of time to produce death.^13–15Our primary objective was to present the patterns of suicide among children and adolescents (aged 10–19 years) in Canada.     

Defining smallness for gestational age in the early years of the Danish Medical Birth Registry

Background

Being born small for gestational age (SGA) is associated with decreased insulin sensitivity and increased blood pressure in childhood, but the association with clinical disease in early adulthood is less certain. The Danish Medical Birth Registry has registered all births in Denmark since 1973, but due to variable data quality, data is most often used only from 1981 onwards, and birth registers in other countries may have similar problems for the early years. We wanted to examine whether the data can be used for identification of children born SGA and used in future research.

Methodology/Principal Findings

All persons born between 1974 and 1996 were identified in the Danish Medical Birth Registry (n = 1.704.890). Immigrants and children without data on gestational age and birth weight were excluded, and a total of 1.348.106 children were included in the analysis. The difference between the different variables used in the history of the registry were examined, and the quality of data in the birth registry from 1974-1981 was examined and compared to subsequent years.Data on birth weight and gestational age in the early years of the registry is inconsistent, and the identification of children born SGA is inaccurate, with 49% false-positives. The biggest source of error is due to the rough and inaccurate intervals used for gestational age. By using –3 standard deviations as a cut-off for the identification of children born SGA, the number of false-positives was reduced to 9%, while the amount of false-negatives were increased.

Conclusion

Choosing –3 standard deviations for identifying children born SGA is a viable, though not optimal solution for identifying children born SGA. Overall the data in the registry is of sufficient quality to be used in further medical research.     

Mobility of integrin alpha5beta1 measured on the isolated ventral membranes of human skin fibroblasts

We have measured the lateral mobility of individual alpha5 integrin molecules in ventral plasma membranes of fibroblasts, which were prepared by removal of apical surfaces and nuclei followed by elimination of actin filaments with gelsolin, an actin-severing protein. The cytoplasmic domain of individual integrin molecules was tagged with 100 nm fluorescent polystyrene bead, and motion of the bead was observed and video-recorded. Position of the bead in each frame was determined from the centroid of the fluorescence image, from which plots of the mean-square displacement against time intervals were derived. Within short intervals of time (<100 ms) the mean-square displacement was proportional to the time interval, and the averaged translational diffusion coefficient of (5.3+/-4.4) x 10(-10) cm2/s was obtained with a broad distribution of (1.3-20) x 10(-10) cm2/s. The broad distribution might reflect the oligomerized state of integrin. The largest diffusion coefficient was comparable to that of lipid molecules previously measured in cells and probably represented the diffusion of a single integrin molecule in the presence of little interference of actin cytoskeleton or extracellular matrix. In longer time intervals (>100 ms) the motion of the bead was confined in an area, the average diameter of which was 410+/-160 nm. This was similar to the values described in previous reports, in which the motion of other membrane receptors labeled on their extracellular domain was measured in living cells.     

Cost-effectiveness of a family-based GP-mediated intervention targeting overweight and moderately obese children

Objective

To assess from a societal perspective the incremental cost-effectiveness of a family-based GP-mediated intervention targeting overweight and moderately obese children. The intervention was modelled on the LEAP (live, eat and play) trial, a randomised controlled trial conducted by the Centre for Community Child Health, Melbourne, Australia in 2002-2003. This study was undertaken as part of the assessing cost-effectiveness (ACE) in obesity project which evaluated, using consistent methods, 13 interventions targeting unhealthy weight gain in children and adolescents.

Method

A logic pathway was used to model the effects of the intervention compared to no intervention on body mass index (BMI) and health outcomes (disability-adjusted life years—DALYs). Disease costs and health benefits were tracked until the cohort of eligible children reached the age of 100 years or death. Simulation-modelling techniques were used to present a 95% uncertainty interval around the cost-effectiveness ratio. The intervention was also assessed against a series of filters (‘equity’, ‘strength of evidence’, ‘acceptability’, ‘feasibility’, sustainability’ and ‘side-effects’) to incorporate additional factors that impact on resource allocation decisions.

Results

The intervention, as modelled, reached 9685 children aged 5-9 years with a BMI z-score of ≥3.0, and cost $AUD6.3M (or $AUD4.8M excluding time costs). It resulted in an incremental saving of 2300 BMI units which translated to 511 DALYs. The cost-offsets stemming from the intervention totalled $AUD3.6M, resulting in a net cost per DALY saved of $AUD4670 (dominated; $0.1M) (dominated means intervention costs more for less effect).

Conclusion

Compared to a ‘no intervention’ control group, the intervention was cost-effective under current assumptions, although the uncertainty intervals were wide. A key question related to the long-term sustainability of the small incremental weight loss reported, based on the 9-month follow-up results for LEAP.     

血清25-羟维生素D水平与儿童骨密度的相关性研究

目的:研究血清25-羟维生素D[25-(OH)D]水平与儿童骨密度(BMD)的相关性。方法:选择2017年1月到2017年12月在亳州市人民医院接受健康体检的儿童100例作为研究对象。根据血清25-(OH)D水平对维生素D(Vit D)营养状况进行分组,其中严重缺乏组9例,缺乏组28例,不足组42例和充足组21例。对比不同年龄段和不同性别儿童血清25-(OH)D、BMD水平以及不同Vit D营养状况儿童对应的BMD水平,并采用Spearman相关性分析法分析血清25-(OH)D水平与儿童BMD、年龄的相关性。结果:5-9岁和10-14岁儿童的血清25-(OH)D及BMD水平均分别低于1-4岁儿童,而10-14岁儿童又低于5-9岁儿童(P0.05)。男童的血清25-(OH)D及BMD水平均分别高于女童,差异有统计学意义(P0.05)。不足组、缺乏组、严重缺乏组儿童的BMD水平均分别低于充足组,且缺乏组和严重缺乏组低于不足组,严重缺乏组又低于缺乏组(P0.05)。根据Spearman相关性分析结果显示,血清25-(OH)D水平与儿童BMD呈正相关,而与年龄呈负相关(P0.05),年龄与儿童BMD呈负相关(P0.05)。结论:血清25-(OH)D水平与儿童BMD呈正相关,但与年龄则呈负相关,及时补充适量的Vit D以满足儿童的机体所需,有利于儿童健康成长。     

Temporal changes in conscious and unconscious trace phenomena in six to seven-year-old children]

Development in time of unconscious trace reactions as well as a change in the time of reproduction of verbal material in natural conditions was studied by the conditioned reflex to time method on 107 school children aged from six to seven years and on 35 subjects of the same age from a kindergarten. It has been found that in schoolchildren the transfer of trace reactions to long-term storage is completed faster, and their voluntary acts in the course of conscious reproduction of an interstimuli intervals are more adequate than in the kindergarten children of the same age. The trace phenomena formed in natural conditions and in the laboratory experiment develop in time in a similar way. The change in time of conscious trace phenomena is of a more complex nature than of the unconscious phenomena. The practical significance of the data obtained is noted.     

Age-related changes and sex differences in postural control adaptability in children during periodic floor oscillation with eyes closed

We investigated age-related changes and sex differences in adaptability of anticipatory postural control in children. Subjects comprised 449 children (4-12 years old) and 109 young adults (18-29 years old). Subjects stood with eyes closed on a force-platform fixed to a floor oscillator. We conducted five trials of 1-minute oscillation (0.5 Hz frequency, 2.5 cm amplitude) in the anteroposterior direction. Postural steadiness was quantified as the mean speed of the center of pressure in the anteroposterior direction (CoPy). In young adults, CoPy speed decreased rapidly until the third trial for both sexes. Adaptability was evaluated by changes in steadiness. The adaptability of children was categorized as "good," "moderate," and "poor," compared with a standard variation of the mean CoPy speed regression line between the first and fifth trials in young adults. Results were as follows: (1) anticipatory postural control adaptability starts to develop from age 6 in boys and 5 in girls, and greatly improves at age 7-8 in boys and 6 in girls; (2) the adaptability of children at age 11-12 (74% of boys and 63% of girls were categorized as "good") has not yet reached the same level as for young adults; (3) the adaptability at age 11-12 for girls is temporarily disturbed due to early puberty.     

The rate of force development obtained at early contraction phase is not influenced by active static stretching

The objective of this study was to investigate the influence of active static stretching on the maximal isometric muscle strength (maximal voluntary contraction [MVC]) and rate of force development (RFD) determined within time intervals of 30, 50, 100, and 200 milliseconds relative to the onset of muscle contraction. Fifteen men (aged 21.3 ± 2.4 years) were submitted on different days to the following tests: (a) familiarization session to the isokinetic dynamometer; (b) 2 maximal isometric contractions for knee extensors in the isokinetic dynamometer to determine MVC and RFD (control); and (c) 2 active static stretching exercises for the dominant leg extensors (10 × 30 seconds for each exercise with a 20-second rest interval between bouts). After stretching, the isokinetic test was repeated (poststretching). Conditions 2 and 3 were performed in random order. The RFD was considered as the mean slope of the moment-time curve at time intervals of 0-30, 0-50, 0-100; 0-150; and 0200 milliseconds relative to the onset of muscle contraction. The MVC was reduced after stretching (285 ± 59 vs. 271 ± 56 N · m, p < 0.01). The RFD at intervals of 0-30, 0-50, and 0-100 milliseconds was unchanged after stretching (p > 0.05). However, the RFD measured at intervals of 0-150 and 0-200 milliseconds was significantly lower after stretching (p < 0.01). It can be concluded that explosive muscular actions of a very short duration (<100 milliseconds) seem less affected by active static stretching when compared with actions using maximal muscle strength.