Annual high-dose vitamin D3 and mental well-being: randomised controlled trial

Background Epidemiological evidence supports a relationship between vitamin D and mental well-being, although evidence from large-scale placebo-controlled intervention trials is lacking.

Aims To examine if vitamin D supplementation has a beneficial effect on mood in community-dwelling older women; if a single annual large dose of vitamin D has a role in the prevention of depressive symptoms; and if there is an association between serum 25-hydroxyvitamin D levels and mental health.

Method A double-blind, randomised, placebo-controlled trial of women aged 70 or older (the Vital D Study: ISRCTN83409867 and ACTR12605000658617). Participants were randomly assigned to receive 500 000 IU vitamin D3 (cholecalciferol) orally or placebo every autumn/winter for 3–5 consecutive years. The tools utilised at various time points were the General Health Questionnaire, the 12-item Short Form Health Survey, the Patient Global Impression–Improvement scale and the WHO Well-Being Index. Serum 25-hydroxyvitamin D levels were measured in a subset of 102 participants.

Results In this non-clinical population, no significant differences between the vitamin D and placebo groups were detected in any of the measured outcomes of mental health. Serum 25-hydroxyvitamin D levels in the vitamin D group were 41% higher than the placebo group 12 months following their annual dose. Despite this difference, scores from the questionnaires did not differ. Furthermore, there was no interaction between those on antidepressant/anxiety medication at baseline and the treatment groups.

Conclusions The lack of improvement in indices of mental well-being in the vitamin D group does not support the hypothesis that an annual high dose of vitamin D3 is a practical intervention to prevent depressive symptoms in older community-dwelling women.

Pre-exercise carbohydrate ingestion : effect of the glycemic index on endurance exercise performance

Purpose: This study aimed to examine the effect of glycemic index of pre-exercise carbohydrate (CHO) ingestion on exercise metabolism and performance.

Methods: Eight endurance trained men ingested a high glycemic index (HGI), low glycemic index (LGI), or a placebo (CON) meal 45 min before exercise and then cycled for 50 min at 67% V·O_2max. Subjects subsequently performed a 15-min self-paced performance ride in which total work (kJ) was recorded.

Results: Plasma glucose concentrations were higher (P < 0.01) after ingestion in HGI compared with LGI and CON (7.53 ± 0.64 vs 5.55 ± 0.21 and 4.65 ± 0.14 mmol·L^-1 for HGI, LGI, and CON, respectively, 30 min postprandial; mean ± SE) but declined at the onset of exercise and were lower (P < 0.01) compared with LGI and CON (4.03 ± 0.31 vs 4.64 ± 0.24 and 5.09 ± 0.16 mmol·L^-1 for HGI, LGI, and CON respectively; mean ± SE) at 10 min of exercise. Plasma glucose remained depressed (P < 0.01) until 30 min into exercise in HGI compared with other trials. Plasma insulin concentrations were higher (P < 0.01) following ingestion during rest and exercise in HGI compared with LGI and CON. Plasma FFA concentrations were lower (P < 0.05) following ingestion in HGI and LGI compared with CON and higher (P < 0.05) in LGI compared with HGI at the start and end of exercise. RER and CHO oxidation was higher (P < 0.01) in HGI compared with LGI and CON during submaximal exercise. There were no differences in work output during the performance cycle.


Conclusions: These data indicate that pre-exercise CHO feedings with varying glycemic indexes do not affect exercise performance following short term submaximal exercise despite alterations in metabolism.

Short-term bone biochemical response to a single bout of high-impact exercise

Bone response to a single bout of exercise can be observed with biochemical markers of bone formation and resorption. The purpose of this study was to examine the response of bone biochemical markers to a single bout of exhaustive high-impact exercise. 15 physically active young subjects volunteered to participate. The subjects performed continuous bilateral jumping with the ankle plantarflexors at 65 % of maximal ground reaction force (GRF) until exhaustion. Loading was characterized by analyzing the GRF recorded for the duration of the exercise. Venous blood samples were taken at baseline, immediately after, 2h and on day 1 and day 2 after the exercise. Procollagen type I amino terminal propeptide (P1NP, marker of bone formation) and carboxyterminal crosslinked telopeptide (CTx, marker of bone resorption) were analyzed from the blood samples. CTx increased significantly (32 %, p = 0.015) two days after the exercise and there was a tendensy towards increase seen in P1NP (p = 0.053) one day after the exercise. A significant positive correlation (r = 0.49 to 0.69, p ≤ 0.038) was observed between change in P1NP from baseline to day 1 and exercise variables (maximal slope of acceleration, body weight (BW) adjusted maximal GRF, BW adjusted GRF exercise intensity and osteogenic index). Based on the two biochemical bone turnover markers, it can be concluded that bone turnover is increased in response to a very

Seventy-year-old habitual volleyball players have larger tibial cross-sectional area and may be differentiated from their age-matched peers by the osteogenic index in dynamic performance

The osteogenicity of a given exercise may be estimated by calculating an osteogenic index (OI) consisting of magnitude and rate of strain. Volleyball involves repetitive jumping and requires high power output and thus may be expected to be beneficial to bone and performance. The purpose of the present study was to examine if habitual volleyball playing is reflected in OI. Ten elderly habitual volleyball players [age 69.9 (SD 4.4) years] and ten matched controls volunteered [age 69.7 (4.2) years] as subjects. Distal tibia (d), tibial mid-shaft (50) and femoral neck (F) bone characteristics were measured using pQCT and DXA. To estimate skeletal rigidity, cross-sectional area (ToA50), and compressive (BSId) and bending strength indices (SSImax50) were calculated. Maximal performance was assessed with eccentric ankle plantar flexion, isometric leg press and countermovement jump (CMJ). A fast Fourier transform (FFT) was calculated from the acceleration of the center of mass during the CMJ. Maximal acceleration (MAG) and mean magnitude frequency (MMF) were selected to represent the constituents of OI. OI was calculated as the sum of the products of magnitudes and corresponding frequencies. Volleyball players had 7% larger ToA50 and 37% higher power in CMJ, 15% higher MAG and 36% higher OI (P B 0.047) than the matched controls. No difference was observed in leg press, plantar flexion or the MMF (P C 0.646). In conclusion, habitual volleyball players may be differentiated from their matched peers by their dynamic jumping performance, and the differences are reflected in the magnitude but not rate of loading.

Northward migration of Afro-Siberian Knots Calidris canutus canutus : high variability in Red Knot numbers visiting staging sites on the French Atlantic coast, 1979–2009

The Afro–Siberian Red Knot subspecies, Calidris canutus canutus, winters mainly on Banc d’Arguin, Mauritania, West Africa. An International Wader Study Group project carried out in 1979 suggested that during northward migration Red Knots cover their migration between the wintering grounds and the Siberian breeding grounds in two long-distance non-stop flights, stopping only in the Wadden Sea in Schleswig-Holstein, Germany. Each year Red Knots also visit staging sites along the French Atlantic coast in addition to the German Wadden Sea. Ever since 1979, the French staging sites have been counted on a regular basis and here we present the count data from these 30 years. In some years more than 20% of the population used the French Atlantic coast as a staging site, but numbers are highly variable from one year to the next. We suggest that high numbers in France might occur when birds have to stop short of the Wadden Sea because of head-winds and/or a lack of tail-winds en route from West Africa.

High pressure measurements of the refractive indices of two nematic liquid crystals

The refractive indices of two nematogens, 4-methoxy-benzylidene-4 prime -n-butylaniline (MBBA) and 4-n-pentyl-4 prime -cyanobiphenyl (5CB), were measured throughout their nematic ranges at pressures up to 2 kbar and temperatures up to 70 degree C in the first substance and up to 5 kbar and 145 degree C in the second. Measurements were made at lambda equals 5,890 A, using a sensitive interference fringe technique. Results are presented in the form of functions n//e(P, T) for the extraordinary index and n//o (P, T) for the ordinary index, obtained by least squares fits to the experimental data.

The devil in high heels : drugs, symbolism and Kate Moss

This paper contributes to critical voices on the issue of organisational responses to drugs and employee drug use. It does so by exploring some of the symbolism residing at the heart of organisations’ relations with drugs and drug taking. Our focus is recent media coverage of, and organisational responses to, the UK tabloid media’s exposé of fashion supermodel Kate Moss’s cocaine use. We use this case to explore symbolic relationships between drugs, sex and femininity, and organisation. Through highlighting these symbolic connections we question further the rationality of organisational responses to the ‘spectre’ of drugs and the issue of employee drug use. We conclude by suggesting that workforce drug testing regimes might be fruitfully seen as mechanisms for scapegoating and sacrifice in order to protect the organizational moral order.

Elevated levels of triglyceride and triglyceride-rich lipoprotein triglyceride induced by a high-carbohydrate diet is associated with polymorphisms of AP0A5-1131T>C and AP0C3-482C> in chinese healthy young adults

Background/aims: Changes in lipid profiles have been shown to be associated with diet and apolipoprotein (APO) polymorphisms. Therefore, 2 polymorphisms, i.e. APOA5-1131T>C and APOC3-482C>T, and serum lipids were examined in a Chinese healthy young population with high-carbohydrate/low-fat (HC/LF) diet intervention.

Methods: After a wash-out diet for 7 days, 56 young adults (22.89 +/- 1.80 years) received the HC/LF diet for 6 days. Body mass index (BMI) and fasting serum lipid profiles at baseline, after the wash-out diet, and after the HC/LF diet were measured.

Results: APOA5-1131C carriers had higher triglyceride (TG) and TG-rich lipoprotein TG (TRL-TG) levels at baseline and after the HC/LF diet, though this mainly corresponded to the female cohort. APOC3-482T carriers had higher TRL-TG levels following the wash-out and HC/LF diets, but these were not directly attributable to a single gender.

Conclusions: Both polymorphisms may play an important role in the elevated TG and TRL-TG levels induced by the HC/LF diet, especially in females, thus indicating a potential dietary prevention of coronary heart disease in this Chinese cohort.

Effects of lipoprotein lipase gene variations, a high-carbohydrate low-fat diet, and gender on serum lipid profiles in healthy Chinese Han youth

A high-carbohydrate low-fat (HC/LF) diet and lipoprotein lipase gene (LPL) Ser447Stop and Hind III polymorphisms have separately been found to be associated with triacylglycerol (TG) and high density lipoprotein cholesterol (HDL-C). This study sought to test the effects of LPL polymorphisms and an HC/LF diet on the serum lipid profile of Chinese with a lower incidence of coronary artery disease (CAD) consuming a diet with less fat and more carbohydrates. Fifty-six healthy subjects (22.89 ± 1.80 years) were given a control diet of 30.1% fat and 54.1% carbohydrates for 7 days, followed by an HC/LF diet of 13.8% fat and 70.1% carbohydrate for 6 days; there were no changes in the fatty acid composition or restrictions on total energy. Serum lipid profiles at baseline, before and after the HC/LF diet, and LPL polymorphisms were analyzed. After 6 days of the HC/LF diet, TG and the homeostasis model assessment of insulin resistance (HOMAIR) index were found to increase only in females with S447S. No decrease in HDL-C was noted. In subjects with Hind III polymorphism, increased TG was found in all females but not in males. Increased HDL-C, together with apolipoprotein (apo) AI, was found in male H- carriers but not in males with H+/H+ and females. In conclusion, LPL Ser447Stop and Hind III polymorphisms modified the effects of an HC/LF diet on the serum lipid profiles of a young Chinese population in different ways. Effective strategies for dietary interventions targeted at younger populations should take into account the interplay between genetic polymorphisms, diet, and gender.

Scores on the dietary guideline index for children and adolescents are associated with nutrient intake and socio-economic position but not adiposity 1-3

Diet quality indices reflect overall dietary patterns better than single nutrients or food groups. The study aims were to develop a measure of adherence with dietary guidelines applicable to child and adolescent populations in Australia and determine the association between index scores and food and nutrient intake, socio-demographic characteristics, and measures of adiposity. Data were analyzed from 4- to 16-y-old participants of the 2007 Australian Children’s Nutrition and Physical Activity Survey (n = 3416). The Dietary Guideline Index for Children and Adolescents (DGI-CA) comprises 11 components: 5 core food groups, wholegrain bread, reduced-fat dairy foods, extra foods (nutrient poor and high in fat, salt, and added sugar), healthy fats/oils, water, and diet variety (possible score of 100). The index criteria were age specific. The mean DGI-CA score was low (53.6 ± 0.4), similar between boys and girls, and differed by age; the youngest children scored higher than the oldest children (P < 0.0001). Higher DGI-CA scores were associated with lower energy intake, energy density, total and saturated fat, and sugar intake; higher protein, carbohydrate, fiber, calcium, iron, vitamin C, vitamin A, folate, phosphorous, magnesium, zinc, and iodine intakes; and a higher polyunsaturated:saturated fat ratio (P < 0.0001). DGI-CA scores were associated with socio-economic characteristics and measures of family circumstance. Weak positive associations were observed between DGI-CA score and BMI or waist circumference Z-scores in the 4- to 10-y and 12- to 16-y age groups only. This index is the first validated index in Australia and one of the few international indices to describe the diet quality of children and adolescents.

The high prevalence of vitamin D insufficiency across Australian populations is only partly explained by season and latitude

Background Inadequate sun exposure and dietary vitamin D intake can result in vitamin D insufficiency. However, limited data are available on actual vitamin D status and predictors in healthy individuals in different regions and by season.

Methods We compared vitamin D status [25-hydroxyvitamin D; 25(OH)D] in people < 60 years of age using data from cross-sectional studies of three regions across Australia: southeast Queensland (27°S; 167 females and 211 males), Geelong region (38°S; 561 females), and Tasmania (43°S; 432 females and 298 males).

Results The prevalence of vitamin D insufficiency (≤ 50 nmol/L) in women in winter/spring was 40.5% in southeast Queensland, 37.4% in the Geelong region, and 67.3% in Tasmania. Season, simulated maximum daily duration of vitamin D synthesis, and vitamin D effective daily dose each explained around 14% of the variation in 25(OH)D. Although latitude explained only 3.9% of the variation, a decrease in average 25(OH)D of 1.0 (95% confidence interval, 0.7–1.3) nmol/L for every degree increase in latitude may be clinically relevant. In some months, we found a high insufficiency or even deficiency when sun exposure protection would be recommended on the basis of the simulated ultraviolet index.

Conclusion Vitamin D insufficiency is common over a wide latitude range in Australia. Season appears to be more important than latitude, but both accounted for less than one-fifth of the variation in serum 25(OH)D levels, highlighting the importance of behavioral factors. Current sun exposure guidelines do not seem to fully prevent vitamin D insufficiency, and consideration should be given to their modification or to pursuing other means to achieve vitamin D adequacy.

The neighborhood social environment and body mass index among youth : a mediation analysis

Background

This study aimed to examine associations between aspects of the neighborhood social environment and body mass index (BMI) in youth both cross-sectionally and prospectively; and whether this association was mediated by physical activity, screen-time and sedentary time.
Methods

Data were collected in 2004 and 2006 in high and low socio-economic areas of Melbourne, Australia. In 2004, 185 children aged 8-9 years (47% boys) and 359 children aged 13-15 years (45% boys) participated. Parents reported their perceptions of aspects of the social environment (i.e. social networks and social trust/cohesion), and physical activity (i.e. time spent outdoors by their children; and their younger children's walking and cycling trips) and screen-time (i.e. TV viewing, computer use). The older children self-reported their walking and cycling trips and their screen-time. All children wore an accelerometer to objectively assess outside-school hours moderate- to-vigorous physical activity and sedentary time. BMI was calculated from height and weight measured in 2004 and 2006. Multilevel linear regression analyses were conducted to examine associations between the social environment and BMI. Mediation analyses using the products of coefficient method were conducted to determine whether associations between the social environment and BMI were mediated by the time spent in a range of physical activity and sedentary behaviors.
Results

Cross-sectional and prospective regression analyses showed that a more positive social network and higher social trust/cohesion was related to lower BMI among children. There was no evidence that time spent in physical activity or sedentary behaviors mediated this relation, despite significant associations between social networks and screen-time and between screen-time and BMI.
Conclusions

The findings suggest that the neighborhood social environment may be important for preventing overweight and obesity in children. Further research investigating the mechanisms through which the neighborhood social environment exerts its effect on BMI is needed.

The development of the Melbourne low vision ADL index : a measure of vision disability

PURPOSE. To develop a new test of activities of daily living (ADLs) appropriate for the low-vision population: the Melbourne Low-Vision ADL Index (MLVAI).

METHODS. The MLVAI was designed as a desk-based clinical assessment, comprising 18 observed items on complex ADLs in part (a) and 9 questions on broad self-care ADLs in part (b). Each item was rated on a five-level descriptive scale from 0 to 4, based on independence, speed, and accuracy of performance. It was designed to be administered under standardized conditions with regard to the instructions, illumination, and working distances. The validity and reliability of the new MLVAI was determined for 122 subjects who were representative of the general low-vision population, in a cross-sectional study.

RESULTS. Two items were found to be redundant and were eliminated from the test. Thus, the final test comprised 25 items, with 100 being the highest possible score. Cronbach’s α indicated an internal reliability of 0.96, and an intraclass correlation coefficient indicated an overall reliability of 0.95. The SE of measurement was 4.5. According to Spearman’s correlation coefficient, the test–retest reliability was 0.94 (P < 0.001), and the interpractitioner reliability for five different pairs of practitioners was 0.90 or higher (P < 0.001). With regard to validity, there was a moderately high correlation with vision impairment (r = −0.68, P < 0.001). Using Rasch analysis, content validity was also demonstrated by good separation indexes (4.70 and 9.88) and high reliability scores (0.96 and 0.99) for the person and items parameters, respectively. Separate calculation of indexes and reliability scores for parts (a) and (b) indicated high content validity and reliability of each part. However, the separation indexes and reliability scores were higher for part (a) than for part (b). The correlation coefficient for part (a) and part (b) was 0.68.

CONCLUSIONS. The MLVAI is a highly valid and reliable standardized test of ADL performance for the general low-vision population. It may be used to assess patients with low vision and has the potential to be used as a measure of low-vision rehabilitation outcomes.

A weighted version of the Melbourne low-vision ADL index : a measure of disability impact

Objective. To develop a version of the Melbourne Low-Vision ADL Index that measures the personal impact of disability in activities of daily living (ADL's). Also, to determine the relationship between clinical measures of vision impairment and disability impact.

Methods. The Melbourne Low-Vision ADL Index (MLVAI) is a desk-based clinical assessment of disability in ADL's. Ability to perform each item is rated on a five-level descriptive scale from zero to four. In this study, the original version of the MLVAI was modified to measure disability impact. The simple modification involved weighting each item by the importance of that item to the person being tested. Importance was also rated on a five-level scale from zero to four. The validity and reliability of the Weighted Melbourne Low-Vision ADL Index (MLVAIW) was determined for 97 vision-impaired subjects in a cross-sectional study.

Results. Cronbach's alpha coefficient indicated an internal reliability of 0.94, and an intraclass correlation coefficient indicated an overall reliability of 0.88. The standard error of measurement was 24.7 points (out of a possible score of 400). There was a statistically significant difference in test scores between normal subjects and vision-impaired subjects. All vision measures had a high, statistically significant correlation with MLVAIW score. Near-word acuity had the strongest correlation (rs = 0.78, p < 0.001), followed by Melbourne Edge Test contrast sensitivity (rs = -0.72, p < 0.001). Visual field had the weakest correlation (rs = -0.52, p < 0.001). The best predictive model of MLVAIW score incorporated the variables age, near-word acuity, and visual field. Together, these variables accounted for 65.1% of the variance in MLVAIW score.

Conclusions. The MLVAI is highly valid and reliable when weighted by a scale that reflects the personal importance of ADL's. The MLVAIW can provide information over and above that obtained with the usual clinical vision measures and may be used to assess low-vision patients and to measure low-vision rehabilitation outcomes. It is suggested that the assessment of disability using the original MLVAI and the assessment of the impact of disability using the MLVAIW should be kept separate to facilitate the clear interpretation of the outcomes of low-vision rehabilitation.

The personal wellbeing index : psychometric equivalance for adults and school children

Despite the wealth of accumulated research evaluating subjective wellbeing (SWB) in children and adults, the validity of scores from parallel forms of SWB measures for each age group has yet to be empirically tested. This study examines the psychometric equivalence of the child and adult forms of the personal wellbeing index (PWI) using multiple-group confirmatory factor analysis. The child sample comprised 1,029 Victorian high-school students (aged 11–20) sampled across three independent studies. The adult sample comprised 1,965 Australian adults drawn from the Australian Unity Wellbeing Index. The results demonstrated strict factorial invariance between both versions, suggesting that the PWI measures the same underlying construct in adolescent and adult populations. These findings provide support for quantitative comparisons between adult and adolescent SWB data as valid.