Iodothyronines influence lipid metabolism and energy homeostasis. Previous studies demonstrated that 3,5-l-diiodothyronine (T(2)), as well as 3,3',5-L-triiodothyronine (T(3)), was able to both prevent and reverse hepatic steatosis in rats fed a high-fat diet, and this effect depends on a direct action of iodothyronines on the hepatocyte. However, the involvement of thyroid hormone receptors (TRs) in mediating the lipid-lowering effect of iodothyronines was not elucidated. In this study, we investigated the ability of T(2) and T(3) to reduce the lipid overloading using the rat hepatoma FaO cells defective for functional TRs. The absence of constitutive mRNA expression of both TRα1 and TRβ1 in FaO cells was verified by RT-qPCR. To mimic the fatty liver condition, FaO cells were treated with a fatty acid mixture and then exposed to pharmacological doses of T(2) or T(3) for 24 h. Lipid accumulation, mRNA expression of the peroxisome proliferator-activated receptors (PPAR-α, -γ, -δ) the acyl-CoA oxidase (AOX), and the stearoyl CoA desaturase (SCD1), as well as fuel-stimulated O(2) consumption in intact cells, were evaluated. Lipid accumulation was associated with an increase in triacylglycerol content, PPARγ mRNA expression, and a decrease in PPARδ and SCD1 mRNA expression. The addition of T(2) or T(3) to lipid-overloaded cells resulted in i) reduction in lipid content; ii) downregulation of PPARα, PPARγ, and AOX expression; iii) increase in PPARδ expression; and iv) stimulation of mitochondrial uncoupling. These data demonstrate, for the first time, that in the hepatocyte, the lipid-lowering actions of both T(2) and T(3) are not mediated by TRs.

A 70-day experiment was performed with Daphnia magna exposed to waterborne Am-241 on a range of concentrations (from 0.4 to 40 Bq ml-1) in order to test chronic effects of internal alpha irradiation on respiration, somatic growth and reproduction over three successive generations. Changes in Am-241 concentrations were followed in the water and in daphnid tissues, eggs and cuticles. Corresponding average dose rates of 0.3, 1.5 and 15 mGy h-1 were estimated. This study confirmed that oxygen consumption increased significantly in the first generation (F0) after 6 days of exposure to a dose rate ≥1.5 mGy h-1. Consequences were limited to a reduction in body length (5%) and dry mass of females (16%) and eggs (8%) after 23 days of exposure, while mortality and fecundity remained unaffected. New cohorts were started with neonates of broods 1 and 5, to examine potential consequences of the reduced mass of offspring for subsequent exposed generations. Results strongly contrasted with those observed in F0. At the highest dose rate, an early mortality of 38-90% affected juveniles while survivors showed delayed reproduction and reduced fecundity in F1 and F2. At 0.3 and 1.5 mGy h-1, mortality ranged from 31 to 38% of daphnids depending on dose rate, but was observed only in generation F1 started with neonates of the brood 1. Reproduction was affected through a reduction in the proportion of breeding females, occurring in the first offspring generation at 1.5 mGy h-1 (to 62% of total daphnids) and in the second generation at 0.3 mGy h-1 (to 69% of total daphnids). Oxygen consumption remained significantly higher at dose rates ≥0.3 mGy h-1 than in the control in almost every generation. Body size and mass continued decreasing in relation to dose rate, with a significant reduction in mass ranging from 15% at 0.3 mGy h-1 to 27% at 15 mGy h-1 in the second offspring generation. © 2008 Elsevier B.V. All rights reserved.

Many biological seep studies focused on the distribution, structure, nutrition and food web architecture of seep communities as well as on their interaction with the seep geochemistry. However, overall respiration at cold seeps received only little attention. We conducted in-situ oxygen flux measurements in combination with ex-situ oxygen micro-profiles, respiration measurements, as well as rate determinations of microbial methane and sulfate turnover to assess respiration pathways as well as carbon turnover at a seep habitat that was recently discovered alongside the Hikurangi Margin offshore northern New Zealand. This habitat is dominated by dense beds of tube-building, heterotrophic ampharetid polychaetes. Average total oxygen uptake (TOU) from this habitat was very high (83.7 mmol m- 2day- 1). TOU at a non-seep reference site ranged between 2.7 and 5.8 mmol m- 2day- 1. About 37% (30.8 mmol m- 2day- 1) of the average TOU was consumed by ampharetids. Considering mean diffusive oxygen uptake (8.5 mmol m- 2day- 1) the remaining fraction of ~ 53% of the TOU (44.4 mmol m- 2day- 1) might be explained by respiration of epibenthic organisms as well as aerobic methane and sulfide oxidation at the sediment-water interface. The strongly negative carbon isotopic signatures (- 52.9 ± 5‰ VPDB) of the ampharetid tissues indicate a methane derived diet. However, carbon production via anaerobic oxidation of methane (AOM) was too low (0.1 mmol C m- 2day- 1) to cover the mean carbon demand of the ampharetid communities (21 mmol C m- 2day- 1). Likely, organic carbon generated via aerobic methane oxidation represents their major carbon source. This is in contrast to other seep habitats, where energy bound in methane is partly transferred to sulfide via AOM and finally consumed by sulfide-oxidizing chemoautotrophs providing carbon that subsequently enters the benthic food web. © 2009 Elsevier B.V. All rights reserved.

Although almost 90% of the world population of children and adolescents live in low-and middle-income countries, few trials of psychosocial interventions to prevent child mental health problems have been conducted in these countries. 1 Early-onset conduct problems are the most common mental health concern in childhood, affecting 5-8% of the population at the severity level for an ICD-10 diagnosis. 2 Long-term outcomes are very poor, with three-to sixfold increases in the prevalence of adult criminal violence, drug misuse, school failure, teenage pregnancy and unemployment. 3 Although proven preventative interventions exist, they reach few children, even in high-income countries. This problem is amplified in low-and middle-income countries where child mental health services are extremely limited. 4,5 Schools offer a logical setting for interventions for children, and school-based violence prevention programmes in high-income countries have shown significant reductions to children's aggressive and disruptive behaviour and increases in child competencies. Universal interventions promote the mental health of all children, avoid stigmatisation and generally attract community support. 6 However, there is limited information on the effectiveness of these programmes in low-and middle-income countries where schools often have few resources and poor conditions. In Jamaica, violence among youth and adults is particularly prevalent. 7 However, there are good opportunities for early intervention as 98% of 3-to 6-year-old children attend pre-schools so there is potential for almost universal coverage. In pilot studies we implemented the Incredible Years Teacher Training programme and showed large benefits to teachers' practices and to class-wide measures of child behaviour, 8 and also demonstrated that the intervention was acceptable, feasible and relevant. 9 The aim of this study was to evaluate on a larger scale the effect of the intervention on the behaviour of high-risk children at home and at school. Method Study design and participants A cluster randomised trial was conducted in the school year in 24 community pre-schools in inner-city areas of Kingston, Jamaica. Over 75% of preschool children in Jamaica attend community pre-schools, which are provided through community organisations with government oversight. Parents pay a small fee and also provide school materials such as books and pencils. Most teachers are paraprofessionals and the schools generally have poor physical conditions, including overcrowding and few teaching and learning materials. We used 'pre-school' as the unit of randomisation to prevent contamination among teachers. Inclusion criteria for pre-schools were: three to four classes of children, at least 20 children per class, situated in a specified geographical area and all teachers consented to the trial. In total, 50 pre-schools were approached and 24 meeting the inclusion criteria were recruited (Fig. 1). Children at high risk for subsequent externalising problems were selected for evaluation. 2 An interviewer-administered screening questionnaire was conducted with each teacher. Teachers rated each child on ten items from the ICD-10 Diagnostic Criteria for Research 10 for conduct disorder (loses temper, back chats, disobedient/breaks rules, annoys others, blames others, easily annoyed, often angry, spiteful to others, fights or bullies and destroys property), using a four-point scale. The three children from each class with the highest scores were enrolled. Background There is an urgent need for effective, affordable interventions to prevent child mental health problems in low-and middle-income countries.

1. The specific respiration rate of 13 chironomid taxa and Chaoborus were measured to test the hypothesis of the relation between a species' ability to regulate their oxygen uptake and their distributional patterns among nine study lakes in British Columbia, Canada. 2. Respiration patterns of individual taxa were modelled using piecewise linear regression with break point and simple hyperbolic functions. Three types of respiration curves were identified: (i) classical oxy-conformers (e.g. littoral Cricotopus) which cannot sustain a sufficient oxygen uptake with decreasing oxygen availability; (ii) oxy-regulators (e.g. profundal Chironomus) which can regulate and maintain a constant respiration until a certain critical point and (iii) oxy-stressors (Micropsectra) which increase their respiration rate with decreasing oxygen availability until a critical point. 3. Respiration was measured at two different temperatures (10 and 20°C), and over the range of oxygen saturation conditions studied here (0-90%) mean Q10 values varied from 1.3 to 2.5. 4. The results show that different chironomid taxa have varying sensitivity to low oxygen concentrations and different respiratory responses to increased temperature. The critical point increased to higher oxygen saturation for six taxa, decreased for one taxon and was unchanged for two taxa. 5. The results illustrate one of the possible biological mechanisms behind the use of chironomids as temperature and climate indicators in palaeoecological studies by exploring the link between temperature and respiration physiology. © 2007 The Authors.