Richard Bélanger

A U-shaped association between intensity of Internet use and adolescent health.

OBJECTIVE: To examine the relationship between different Internet-use intensities and adolescent mental and somatic health. METHODS: Data were drawn from the 2002 Swiss Multicenter Adolescent Survey on Health, a nationally representative survey of adolescents aged 16 to 20 years in post-mandatory school. From a self-administered anonymous questionnaire, 3906 adolescent boys and 3305 girls were categorized into 4 groups according to their intensity of Internet use: heavy Internet users (HIUs; >2 hours/day), regular Internet users (RIUs; several days per week and ≤2 hours/day), occasional users (≤1 hour/week), and non-Internet users (NIUs; no use in the previous month). Health factors examined were perceived health, depression, overweight, headaches and back pain, and insufficient sleep. RESULTS: In controlled multivariate analysis, using RIUs as a reference, HIUs of both genders were more likely to report higher depressive scores, whereas only male users were found at increased risk of overweight and female users at increased risk of insufficient sleep. Male NIUs and female NIUs and occasional users also were found at increased risk of higher depressive scores. Back-pain complaints were found predominantly among male NIUs. CONCLUSIONS: Our study provides evidence of a U-shaped relationship between intensity of Internet use and poorer mental health of adolescents. In addition, HIUs were confirmed at increased risk for somatic health problems. Thus, health professionals should be on the alert when caring for adolescents who report either heavy Internet use or very little/none. Also, they should consider regular Internet use as a normative behavior without major health consequence.

Phenolic compounds that confer resistance to spruce budworm

Phenolic compounds are apparently important in the defence mechanisms of conifers. To test the hypothesis that phenolic compounds in resistant white spruce [Picea glauca (Moench) Voss (Pinaceae)] impart resistance against spruce budworm [Choristoneura fumiferana (Clemens) (Lepidoptera: Tortricidae)], we performed aqueous extractions of current‐year shoots of white spruce that were tolerant of varying levels of budworm defoliation. High‐performance liquid chromatographic profiles of water extracts of P. glauca needles differed between resistant and susceptible trees. Further nuclear magnetic resonance analyses identified two phenolic glucosides in susceptible white spruce, picein [3‐(β‐d‐glucosyloxy)‐hydroxy‐acetophenone] and pungenin [3‐(β‐d‐glucosyloxy)‐4‐hydroxy‐acetophenone], and two phenolics in resistant white spruce, pungenol (3′,4′‐hydroxy‐acetophenone) and piceol (4′‐hydroxyacetophenone). We focused on the performance of spruce budworm when piceol and pungenol were added to the diet. These two compounds significantly reduced larval survival, retarded development, and reduced pupal mass. Food consumption by sixth‐instar spruce budworms was affected by a combination of the phenolic compounds. These results suggest that the two phenolic compounds reduce the pressure of spruce budworm herbivory on specific host tree phenotypes. Thus, the mechanism of defence in P. glauca apparently reflects a strategy of constitutive resistance.

Pythium attrantheridium sp. nov.: taxonomy and comparison with related species.

Pythium attrantheridium sp. nov. is a new species isolated from cavity spot lesions of carrots as well as apple and cherry seedlings from various locations widely distributed in Canada and the USA. This fungus is closely related to the heterothallic P. intermedium, but is distinguished by: (1) unique molecular characteristics; (2) unique morphological characteristics; and (3) mating incompatibility with P. intermedium. The ITS region of the nuclear rDNA of all strains of P. attrantheridium studied is different from that of all other known Pythium spp. The oogonia attract a large number of antheridia when compatible mating types contact each other. The positive mating type produces zoospores unlike those of P. intermedium. Thus, biological, morphological and molecular data support the recognition of a new species.

Aquaporins Mediate Silicon Transport in Humans

In animals, silicon is an abundant and differentially distributed trace element that is believed to play important biological functions. One would thus expect silicon concentrations in body fluids to be regulated by silicon transporters at the surface of many cell types. Curiously, however, and even though they exist in plants and algae, no such transporters have been identified to date in vertebrates. Here, we show for the first time that the human aquaglyceroporins, i.e., AQP3, AQP7, AQP9 and AQP10 can act as silicon transporters in both Xenopus laevis oocytes and HEK-293 cells. In particular, heterologously expressed AQP7, AQP9 and AQP10 are all able to induce robust, saturable, phloretin-sensitive silicon transport activity in the range that was observed for low silicon rice 1 (lsi1), a silicon transporter in plant. Furthermore, we show that the aquaglyceroporins appear as relevant silicon permeation pathways in both mice and humans based on 1) the kinetics of substrate transport, 2) their presence in tissues where silicon is presumed to play key roles and 3) their transcriptional responses to changes in dietary silicon. Taken together, our data provide new evidence that silicon is a potentially important biological element in animals and that its body distribution is regulated. They should open up original areas of investigations aimed at deciphering the true physiological role of silicon in vertebrates.

To What Extent Does Adding Tobacco to Cannabis Expose Young Users to Nicotine

INTRODUCTION To determine if mulling, the process of adding tobacco to cannabis for its consumption, exposes young cannabis users to significant levels of nicotine. METHODS This observational study performed in 2009-2010 among Swiss youths aged 16-25 years involved the completion of a self-administrated questionnaire and the collection of a urine sample on the same day. Measures of urinary cotinine were blindly performed using liquid chromatography coupled-mass spectrometry. A total of 197 eligible participants were divided in 3 groups based on their consumption profile in the past 5 days: 70 abstainers (ABS) not having used cigarettes or cannabis, 57 cannabis users adding tobacco to the cannabis they smoke (MUL) but not having smoked cigarettes, and 70 cigarette smokers (CIG) not having smoked cannabis. RESULTS Exposure to nicotine was at its lowest among ABS with a mean (SE) cotinine level of 3.2 (1.4) ng/ml compared, respectively, with 214.6 (43.8) and 397.9 (57.4) for MUL and CIG (p < .001). While consumption profile appeared as the only significant factor of influence when examining nicotine exposure from the ABS and MUL participants on multivariate analysis, it did not result in substantial differences among MUL and CIG groups. CONCLUSIONS Urinary cotinine levels found among MUL are high enough to indicate a significant exposure to nicotine originating from the mulling process. In line with our results, health professionals should pay attention to mulling as it is likely to influence cannabis and cigarette use as well as the efficacy of cessation interventions.

Weekly sport practice and adolescent well-being

Objective Sport practice is widely encouraged, both in guidelines and in clinical practice, because of its broad range of positive effects on health. However, very limited evidence directly supports this statement among adolescents and the sport duration that we should recommend remains unknown. We aimed to determine sport durations that were associated with poor well-being. Methods We conducted a survey including 1245 adolescents (16–20 years) from the general Swiss population. Participants were recruited from various settings (sport centres, peers of sport practicing adolescents, websites) and asked to complete a web-based questionnaire. Weekly sport practice was categorised into four groups: low (0–3.5 h), average (≈ recommended 7 h (3.6–10.5)), high (≈14 h (10.6–17.5)) and very high (>17.5 h). We assessed well-being using the WHO-5 Well-Being Index. Results Compared with adolescents in the average group, those in the very high group had a higher risk of poor well-being (OR 2.29 (95% CI 1.11 to 4.72)), as did those in the low group (OR 2.33 (1.58 to 3.44)). In contrast, those in the high group had a lower risk of poor well-being than those in the average group (OR 0.46 (0.23 to 0.93)). Conclusions We found an inverted, U-shaped relationship between weekly sport practice duration and well-being among adolescents. The peak scores of well-being were around 14 h per week of sport practice, corresponding to twice the recommended 7 h. Practicing higher sport durations was an independent risk factor of poor well-being.

Social contexts of sports-practicing youths' hazardous drinking

Sports-practicing youths are at an elevated risk for alcohol use and misuse. Although much attention has recently been given to depicting subgroups facing the greatest threats, little evidence exists on the contexts in which their drinking takes place. Using data from a cross-sectional study on youth sports participation and substance use in the French-speaking part of Switzerland, this study focused on the social contexts associated with hazardous drinking of 894 sports-practicing adolescents aged 16 to 20. Divided between those who had been drunk in the last month (hazardous drinkers, n = 315) and those who had not (n = 579), sports-practicing adolescents were compared on reported gatherings (sports-related, sports-unrelated, mixed) likely linked to their drinking behaviour. Mixed social contexts, followed by sports-unrelated ones, were reported as the most common context by both male and female youths who practiced sports. After controlling for several possible confounders, male hazardous drinkers were more than 3 times more likely to report sports-unrelated social contexts as the most common, compared to sport-related ones, while females were more than 7 times more likely to do so. Our findings seem to indicate that, rather than focusing only on sports-related factors, prevention of alcohol misuse among sports-practicing youths should also pay attention to the social contextualisation of their hazardous drinking.

Body Dissatisfaction on Top of Depressive Mood among Adolescents with Severe Dysmenorrhea

OBJECTIVES This study aims to determine whether adolescent girls with severe dysmenorrhea (SD) have different psychological characteristics from their peers. STUDY DESIGN Cross-sectional survey (SMASH 02). SETTINGS Nationally representative sample of adolescents attending post-mandatory education. PARTICIPANTS N = 7548, of whom 3340 were females, aged 16-20 years. INTERVENTION Self-administered, anonymous survey consisted of 565 items on 4 main topics: sociodemographic determinants of health, health status, health behaviors, and health care use. OUTCOMES Body image variables, mental health, and associated variables like sexual abuse and health perceptions. Bivariate analysis and binomial logistic regression controlling for explanatory variables were performed. RESULTS 12.4% (95% confidence interval [CI]: 11.0-14) declared SD. Compared to their peers, subjects with SD were more likely to report depressive symptoms (adjusted odds ratio [AOR]: 1.73; 95% CI: 1.38-2.15), have a higher gynecological age (AOR: 1.13; 95% CI: 1.05-1.20), and attend vocational school (AOR: 1.33; 95% CI: 1.00-1.76). Moreover, the proportion of those reporting dissatisfaction with their body appearance was higher (AOR: 1.50; 95% CI: 1.02-2.22). CONCLUSION Patients with SD not only show a different profile from their peers in terms of their mental health academic track and gynecological age, but they are also more dissatisfied with their body appearance. Clinicians should pay particular attention to patients with SD and offer them a global evaluation, bearing in mind what factors can be associated with SD.

Detached, distraught or discerning? Fathers of adolescents with chronic illness: a review of the literature

Abstract Parenting a child with chronic disease provides a unique set of challenges for both mothers and fathers throughout all phases of the illness. However, fathers of these children are under-represented in existing research. This review focuses on the fathers of children with chronic disease included in 44 original articles. We address the challenges to the father’s role as breadwinner, leader and strength-giver in the family. Three time-periods describe the obstacles fathers tackle when parenting children with chronic disease: a) diagnosis and short-term, characterized by distress, isolation and uncertainty; b) the mastery period, characterized by the struggle to establish routine and by support and spirituality; and c) the long-term, characterized by relationship and personality change, worries and bereavement. Overall, whilst current research has revealed some key themes pertaining to fathers of children with chronic disease, further studies are required to foster the development of support mechanisms for the specific needs of these fathers.

Erratum: Cannabis use in relation to obesity and insulin resistance in the inuit population.

Obesity (2015) 23:290-295. doi: 10.1002/oby.20973 After the Brief Cutting Edge Report above was published, it was noted that in the Introduction section of the article, the sentence “In this population, despite high obesity prevalence (49%)” should have been correctly stated as “In this population, despite an overweight prevalence of 59.2% (including an obesity rate of 29.3%).” The authors apologize for any confusion caused by this error.