The Benthic Chamber experiment in Storfjorden (Norway) 2005 - effects of CO2 on microbes, nanobenthos and meiofauna

Årsliste 2007Carbon capture and storage (CCS) either sub-seabed or in the ocean is considered among the options for reducing future emissions of CO2 to the atmosphere. Such storage does, however, introduce the possibility of CO2 leakage and interaction with marine fauna. It is therefore important to obtain knowledge on possible effects of CO2 that is introduced to the sea floor. Results from experiments on environmental effects of enhanced concentrations of CO2 at the sediment/water interface are presented. The key part of the project was the Japanese Benthic Chamber system (BC) developed to perform experiments with CO2 in sedimentary environments in situ. The BC is equipped with chambers which enclose sections of the sea floor. Two similar experiments were carried out at 400 m depth in Storfjorden, Norway in September, 2005. The pCO2 exposures in the water above the sediment in the chambers were programmed to maintain levels of approximately 5,000 µatm (pH=7.0) and 20,000 µatm (pH=6.3) respectively in two experimental chambers. The pCO2 in the third control chamber was 500 µatm (pH=7.8). This report gives a description of the experiment and the results from measured physical and chemical parameters (pH, NO3, NH4, SiO2 and oxygen) in the water overlying the sediment in the experimental chambers and biological responses (meiobenthos, nanobenthos, bacteria, Archaea, bacterial DNA and ATP, methane production, sulphate reduction) in the chamber sediments. The results from the different research groups and methods clearly show effects of elevated CO2 concentrations on biological processes such as reduced bacterial density and increased nanobenthos densities. Methane formation and sulphate reduction was favoured by the condition in the 5,000 µatm chamberRIT

Quantitative Alterations in Cutaneous Langerhans Cells During the Evolution of Malignant Melanoma of the Skin

Melanomas are associated with a T-cell predominant infiltrate that may cause their regression. Langerhans cells (LC) are essential for initiation and maintenance of specific T-cell- mediated responses in the skin. Therefore, a change in this antigen-presenting LC population may alter the host response. To determine whether the LC population varies during the evolution of primary cutaneous melanoma 32 melanocytic lesions, nevi, and cutaneous melanomas were studied by quantitative immunohistology. The monoclonal antibody, Leu-6, and the avidin biotin complex immunoperoxidase method were used to identify LC. Compared with histologically normal melanoma-adjacent skin, epidermal LC were depleted above “deeply invasive” melanomas but were relatively unchanged above nevi, “early invasive” melanomas, and cutaneous metastatic melanoma nodules. Dermal LC were significantly increased around in situ and “early invasive” melanomas but not around “deeply invasive” melanomas or cutaneous metastatic nodules. Dermal LC are thus associated with early transformed melanocytes and may present neoantigens to T lymphocytes in situ or after LC maturation in the draining lymph node. Melanoma-associated LC decline in number as melanoma progresses

25-hydroxyvitamin D in pregnancy and genome wide cord blood DNA methylation in two pregnancy cohorts (MoBa and ALSPAC)

The aim of the study was to investigate whether maternal mid-pregnancy 25-hydroxyvitamin D concentrations are associated with cord blood DNA methylation. DNA methylation was assessed using the Illumina HumanMethylation450 BeadChip, and maternal plasma 25-hydroxyvitamin D was measured in 819 mothers/newborn pairs participating in the Norwegian Mother and Child Cohort (MoBa) and 597 mothers/newborn pairs participating in the Avon Longitudinal Study of Parents and Children (ALSPAC). Across 473,731CpG DNA methylation sites in cord blood DNA, none were strongly associated with maternal 25-hydroxyvitamin D after adjusting for multiple tests (false discovery rate (FDR) > 0.5; 473,731 tests). A meta-analysis of the results from both cohorts, using the Fisher method for combining p-values, also did not strengthen findings (FDR > 0.2). Further exploration of a set of CpG sites in the proximity of four a priori defined candidate genes (CYP24A1, CYP27B1, CYP27A1 and CYP2R1) did not result in any associations with FDR < 0.05 (56 tests). In this large genome wide assessment of the potential influence of maternal vitamin D status on DNA methylation, we did not find any convincing associations in 1416 newborns. If true associations do exist, their identification might require much larger consortium studies, expanded genomic coverage, investigation of alternative cell types or measurements of 25-hydroxyvitamin D at different gestational time points

Prenatal iron exposure and childhood type 1 diabetes

Acknowledgements: We are grateful to all the participating families in Norway who take part in this on-going cohort study. We thank Dr. Maria Vistnes at Diakonhjemmet Hospital, Oslo, Norway for help with cytokine assays, PM Ueland and Ø Midttun at BEVITAL, Bergen, Norway, for neopterin and KTR assay, and Kathleen Gillespie at Bristol University, UK for confirmatory HLA genotyping. The Norwegian Mother and Child Cohort Study is supported by the Norwegian Ministry of Health and Care Services and the Ministry of Education and Research, NIH/NIEHS (contract no N01-ES-75558), NIH/NINDS (grant no. 1 UO1 NS 047537-01 and grant no. 2 UO1 NS 047537-06A1). The sub-study was funded by a research grant from the Research Council of Norway. The Norwegian Childhood Diabetes Registry is financed by the South-Eastern Norway Regional Health Authority. Dr London was supported by the Intramural Research Program of the NIH, National Institute of Environmental Health Sciences. Dr Størdal was supported by an unrestricted grant from Oak Foundation, Geneva, Switzerland.Peer reviewedPublisher PD

Znf202 Affects High Density Lipoprotein Cholesterol Levels and Promotes Hepatosteatosis in Hyperlipidemic Mice

Background: The zinc finger protein Znf202 is a transcriptional suppressor of lipid related genes and has been linked to hypoalphalipoproteinemia. A functional role of Znf202 in lipid metabolism in vivo still remains to be established. Methodology and Principal Findings: We generated mouse Znf202 expression vectors, the functionality of which was established in several in vitro systems. Next, effects of adenoviral znf202 overexpression in vivo were determined in normo- as well as hyperlipidemic mouse models. Znf202 overexpression in mouse hepatoma cells mhAT3F2 resulted in downregulation of members of the Apoe/c1/c2 and Apoa1/c3/a4 gene cluster. The repressive activity of Znf202 was firmly confirmed in an apoE reporter assay and Znf202 responsive elements within the ApoE promoter were identified. Adenoviral Znf202 transfer to Ldlr-/- mice resulted in downregulation of apoe, apoc1, apoa1, and apoc3 within 24 h after gene transfer. Interestingly, key genes in bile flux (abcg5/8 and bsep) and in bile acid synthesis (cyp7a1) were also downregulated. At 5 days post-infection, the expression of the aforementioned genes was normalized, but mice had developed severe hepatosteatosis accompanied by hypercholesterolemia and hypoalphalipoproteinemia. A much milder phenotype was observed in wildtype mice after 5 days of hepatic Znf202 overexpression. Interestingly and similar to Ldl-/- mice, HDL-cholesterol levels in wildtype mice were lowered after hepatic Znf202 overexpression. Conclusion/Significance: Znf202 overexpression in vivo reveals an important role of this transcriptional regulator in liver lipid homeostasis, while firmly establishing the proposed key role in the control of HDL levels

Lipid-soluble Vitamins A, D, and E in HIV-Infected Pregnant women in Tanzania.

There is limited published research examining lipid-soluble vitamins in human immunodeficiency virus (HIV)-infected pregnant women, particularly in resource-limited settings. This is an observational analysis of 1078 HIV-infected pregnant women enrolled in a trial of vitamin supplementation in Tanzania. Baseline data on sociodemographic and anthropometric characteristics, clinical signs and symptoms, and laboratory parameters were used to identify correlates of low plasma vitamin A (<0.7 micromol/l), vitamin D (<80 nmol/l) and vitamin E (<9.7 micromol/l) status. Binomial regression was used to estimate risk ratios and 95% confidence intervals. Approximately 35, 39 and 51% of the women had low levels of vitamins A, D and E, respectively. Severe anemia (hemoglobin <85 g/l; P<0.01), plasma vitamin E (P=0.02), selenium (P=0.01) and vitamin D (P=0.02) concentrations were significant correlates of low vitamin A status in multivariate models. Erythrocyte Sedimentation Rate (ESR) was independently related to low vitamin A status in a nonlinear manner (P=0.01). The correlates of low vitamin D status were CD8 cell count (P=0.01), high ESR (ESR >81 mm/h; P<0.01), gestational age at enrollment (nonlinear; P=0.03) and plasma vitamins A (P=0.02) and E (P=0.01). For low vitamin E status, the correlates were money spent on food per household per day (P<0.01), plasma vitamin A concentration (nonlinear; P<0.01) and a gestational age <16 weeks at enrollment (P<0.01). Low concentrations of lipid-soluble vitamins are widely prevalent among HIV-infected women in Tanzania and are correlated with other nutritional insufficiencies. Identifying HIV-infected persons at greater risk of poor nutritional status and infections may help inform design and implementation of appropriate interventions

Maternal VDR variants rather than 25-hydroxyvitamin D concentration during early pregnancy are associated with type 1 diabetes in the offspring

This study was supported by the Finnish Academy (grant 127219), the European Foundation for the Study of Diabetes, the Novo Nordisk Foundation, the Diabetes Research Foundation, the EVO funding of the South Ostrobothnia Central Hospital from the Ministry ofHealthand SocialAffairs (EVO1107), the BiomedicumHelsinki Foun- dation, the Jalmari and Rauha Ahokas Foundation, the Yrjö Jahnsson Foundation, the Suoma Loimaranta-Airila Fund, the Onni and Hilja Tuovinen Foundation and the Juho Vainio Foundation