The Common Shrew (Sorex araneus): A neglected host of tick-borne infections?

Although the importance of rodents as reservoirs for a number of tick-borne infections is well established, comparatively little is known about the potential role of shrews, despite them occupying similar habitats. To address this, blood and tick samples were collected from common shrews (Sorex araneus) and field voles (Microtus agrestis), a known reservoir of various tick-borne infections, from sites located within a plantation forest in northern England over a 2-year period. Of 647 blood samples collected from shrews, 121 (18.7%) showed evidence of infection with Anaplasma phagocytophilum and 196 (30.3%) with Babesia microti. By comparison, of 1505 blood samples from field voles, 96 (6.4%) were positive for A. phagocytophilum and 458 (30.4%) for Ba. microti. Both species were infested with the ticks Ixodes ricinus and Ixodes trianguliceps, although they had different burdens: on average, shrews carried almost six times as many I. trianguliceps larvae, more than twice as many I. ricinus larvae, and over twice as many nymphs (both tick species combined). The finding that the nymphs collected from shrews were almost exclusively I. trianguliceps highlights that this species is the key vector of these infections in this small mammal community. These findings suggest that common shrews are a reservoir of tick-borne infections and that the role of shrews in the ecology and epidemiology of tick-borne infections elsewhere needs to be comprehensively investigated

Determinants of Childhood Adiposity: Evidence from the Australian LOOK Study

BACKGROUND To contribute to the current debate as to the relative influences of dietary intake and physical activity on the development of adiposity in community-based children. METHODS Participants were 734 boys and girls measured at age 8, 10 and 12 years for percent body fat (dual emission x-ray absorptiometry), physical activity (pedometers, accelerometers); and dietary intake (1 and 2-day records), with assessments of pubertal development and socioeconomic status. RESULTS Cross-sectional relationships revealed that boys and girls with higher percent body fat were less physically active, both in terms of steps per day and moderate and vigorous physical activity (both sexes p<0.001 for both measures). However, fatter children did not consume more energy, fat, carbohydrate or sugar; boys with higher percent body fat actually consumed less carbohydrate (p = 0.01) and energy (p = 0.05). Longitudinal analysis (combined data from both sexes) was weaker, but supported the cross-sectional findings, showing that children who reduced their PA over the four years increased their percent body fat (p = 0.04). Relationships in the 8 year-olds and also in the leanest quartile of all children, where adiposity-related underreporting was unlikely, were consistent with those of the whole group, indicating that underreporting did not influence our findings. CONCLUSIONS These data provide support for the premise that physical activity is the main source of variation in the percent body fat of healthy community-based Australian children. General community strategies involving dietary intake and physical activity to combat childhood obesity may benefit by making physical activity the foremost focus of attention.The financial support provided by the Commonwealth Education Trust (London, UK) was vital to the completion of this work, and the authors thank the Board of Trustees for supporting them over several years. The authors also thank members of The Canberra Hospital Salaried Staff Specialists Private Practice Fund for their financial contribution to the study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Longitudinal patterns of physical activity in children aged 8 to 12 years: the LOOK study

BACKGROUND Data on longitudinal monitoring of daily physical activity (PA) patterns in youth over successive years is scarce but may provide valuable information for intervention strategies aiming to promote PA. METHODS Participants were 853 children (starting age ~8 years) recruited from 29 Australian elementary schools. Pedometers were worn for a 7-day period each year over 5 consecutive years to assess PA volume (steps per day) and accelerometers were worn concurrently in the final 2 years to assess PA volume (accelerometer counts (AC) per day), moderate and vigorous PA (MVPA), light PA (LPA) and sedentary time (SED). A general linear mixed model was used to examine daily and yearly patterns. RESULTS A consistent daily pattern of pedometer step counts, AC, MVPA and LPA emerged during each year, characterised by increases on school days from Monday to Friday followed by a decrease on the weekend. Friday was the most active and Sunday the least active day. The percentage of girls and boys meeting international recommendations of 11,000 and 13,000 steps/day respectively on a Monday, Friday and Sunday were 36%, 50%, 21% for boys and 35%, 45%, 18% for girls. The equivalent percentages meeting the recommended MVPA of >60 min/day on these days were 29%, 39%, 16% for boys and 15%, 21%, 10% for girls. Over the 5 years, boys were more active than girls (mean steps/day of 10,506 vs 8,750; p<0.001) and spent more time in MVPA (mean of 42.8 vs 31.1 min/day; p<0.001). Although there was little evidence of any upward or downward trend in steps/day from age 8 to 12 years, there was a trend toward lower MVPA, LPA and a corresponding increase in SED from age 11 to 12 years. CONCLUSION A weekly pattern of PA occurred in children as young as age 8 on a day by day basis; these patterns persisting through to age 12. In addition to supporting previous evidence of insufficient PA in children, our data, in identifying the level and incidence of insufficiency on each day of the week, may assist in the development of more specific strategies to increase PA in community based children

Physical Education and Blood Lipid Concentrations in Children: The LOOK Randomized Cluster Trial

BACKGROUND AND OBJECTIVES Elevated blood lipids during childhood are predictive of dyslipidemia in adults. Although obese and inactive children have elevated values, any potentially protective role of elementary school physical education is unknown. Our objective was to determine the effect of a modern elementary school physical education (PE) program on the blood lipid concentrations in community-based children. METHODS In this cluster-randomized controlled trial, 708 healthy children (8.1±0.3 years, 367 boys) in 29 schools were allocated to either a 4-year intervention program of specialist-taught PE (13 schools) or to a control group of the currently practiced PE conducted by generalist classroom teachers. Fasting blood lipids were measured at ages 8, 10, and 12 years and intervention and control class activities were recorded. RESULTS Intervention classes included more fitness work and more moderate and vigorous physical activity than control classes (both p3.36mmol.L(-1),130 mg/dL) was lower in the intervention than control group (14% vs. 23%, p = 0.02). There was also an intervention effect on mean LDL-C across all boys (reduction of 9.6% for intervention v 2.8% control, p = 0.02), but not girls (p = 0.2). The intervention effect on total cholesterol mirrored LDL-C, but there were no detectable 4-year intervention effects on high-density lipoprotein cholesterol or triglycerides. CONCLUSIONS The PE program delivered by specialist teachers over four years in elementary school reduced the incidence of elevated LDL-C in boys and girls, and provides a means by which early preventative practices can be offered to all children. TRIAL REGISTRATION Australia New Zealand Clinical Trial Registry ANZRN12612000027819 https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=347799.Sources of funding were The Commonwealth Education Trust (New Zealand House, London, UK) (http://www.commonwealth.org.uk/) and the Canberra Hospital Salaried Staff Specialists Fund (http://healthresearch.anu.edu.au/documents/PPFVACATION/ppf-major-info-2012.pdf). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Longitudinal patterns of physical activity in children aged 8 to 12 years: The LOOK study

BACKGROUND: Data on longitudinal monitoring of daily physical activity (PA) patterns in youth over successive years is scarce but may provide valuable information for intervention strategies aiming to promote PA. METHODS: Participants were 853 children (starting age ~8 years) recruited from 29 Australian elementary schools. Pedometers were worn for a 7-day period each year over 5 consecutive years to assess PA volume (steps per day) and accelerometers were worn concurrently in the final 2 years to assess PA volume (accelerometer counts (AC) per day), moderate and vigorous PA (MVPA), light PA (LPA) and sedentary time (SED). A general linear mixed model was used to examine daily and yearly patterns. RESULTS: A consistent daily pattern of pedometer step counts, AC, MVPA and LPA emerged during each year, characterised by increases on school days from Monday to Friday followed by a decrease on the weekend. Friday was the most active and Sunday the least active day. The percentage of girls and boys meeting international recommendations of 11,000 and 13,000 steps/day respectively on a Monday, Friday and Sunday were 36%, 50%, 21% for boys and 35%, 45%, 18% for girls. The equivalent percentages meeting the recommended MVPA of >60 min/day on these days were 29%, 39%, 16% for boys and 15%, 21%, 10% for girls. Over the 5 years, boys were more active than girls (mean steps/day of 10,506 vs 8,750; p<0.001) and spent more time in MVPA (mean of 42.8 vs 31.1 min/day; p<0.001). Although there was little evidence of any upward or downward trend in steps/day from age 8 to 12 years, there was a trend toward lower MVPA, LPA and a corresponding increase in SED from age 11 to 12 years. CONCLUSION: A weekly pattern of PA occurred in children as young as age 8 on a day by day basis; these patterns persisting through to age 12. In addition to supporting previous evidence of insufficient PA in children, our data, in identifying the level and incidence of insufficiency on each day of the week, may assist in the development of more specific strategies to increase PA in community based children

Star Clusters in Virgo and Fornax Dwarf Irregular Galaxies

We present the results of a search for clusters in dwarf irregular galaxies in the Virgo and Fornax Cluster using HST WFPC2 snapshot data. The galaxy sample includes 28 galaxies, 11 of which are confirmed members of the Virgo and Fornax clusters. In the 11 confirmed members, we detect 237 cluster candidates and determine their V magnitudes, V-I colors and core radii. After statistical subtraction of background galaxies and foreground stars, most of the cluster candidates have V-I colors of -0.2 and 1.4, V magnitudes lying between 20 and 25th magnitude and core radii between 0 and 6 pc. Using H-alpha observations, we find that 26% of the blue cluster candidates are most likely HII regions. The rest of the cluster candidates are most likely massive (>10^4 Msol) young and old clusters. A comparison between the red cluster candidates in our sample and the Milky Way globular clusters shows that they have similar luminosity distributions, but that the red cluster candidates typically have larger core radii. Assuming that the red cluster candidates are in fact globular clusters, we derive specific frequencies (S_N) ranging from ~0-9 for the galaxies. Although the values are uncertain, seven of the galaxies appear to have specific frequencies greater than 2. These values are more typical of ellipticals and nucleated dwarf ellipticals than they are of spirals or Local Group dwarf irregulars.Comment: 46 pages, 14 figures, 3 tables, accepted by AJ. Higher quality PS version of entire paper available at http://www.astro.washington.edu/seth/dirr_gcs.htm

Effects of Changes in Adiposity and Physical Activity on Preadolescent Insulin Resistance: The Australian LOOK Longitudinal Study

BACKGROUND In a previous longitudinal analysis of our cohort as 8 to 10 year-olds, insulin resistance (IR) increased with age, but was not modified by changes in percent body fat (%BF), and was only responsive to changes in physical activity (PA) in boys. We aimed to determine whether these responses persisted as the children approached adolescence. METHODS In this prospective cohort study, 256 boys and 278 girls were assessed at ages 8, 10 and 12 years for fasting blood glucose and insulin, %BF (dual energy X-ray absorptiometry); PA (7-day pedometers), fitness (multistage run); and pubertal development (Tanner stage). RESULTS From age 8 to 12 years, the median homeostatic model of IR (HOMA-IR) doubled in boys and increased 250% in girls. By age 12, 23% of boys and 31% of girls had elevated IR, as indicated by HOMA-IR greater than 3. Longitudinal relationships, with important adjustments for covariates body weight, PA, %BF, Tanner score and socioeconomic status showed that, on average, for every 1 unit reduction of %BF, HOMA-IR was lowered by 2.2% (95% CI 0.04-4) in girls and 1.6% (95% CI 0-3.2) in boys. Furthermore, in boys but not girls, HOMA-IR was decreased by 3.5% (95%CI 0.5-6.5) if PA was increased by 2100 steps/day. CONCLUSION Evidence that a quarter of our apparently healthy 12 year-old Australians possessed elevated IR suggests that community-based education and prevention strategies may be warranted. Responsiveness of IR to changes in %BF in both sexes during late preadolescence and to changes in PA in the boys provides a specific basis for targeting elevated IR. That body weight was a strong covariate of IR, independent of %BF, points to the importance of adjusting for weight in correctly assessing these relationships in growing children.Financial support was provided by the Commonwealth Education Trust (London, UK), the Board of Trustees and The Canberra Hospital Salaried Staff Specialists Private Practice Fund. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript