100 YEARS OF VITAMIN D: Combined hormonal contraceptives and vitamin D metabolism in adolescent girls.

Objective: Combined hormonal contraceptive (CHC) use has been associated with higher total 25-hydroxyvitamin D (25(OH)D) levels. Here, we investigate the relation between CHC use and vitamin D metabolism to elucidate its clinical interpretation.

Methods: The cross-sectional Fit Futures 1 included 1038 adolescents.

Vitamin D supplementation has no effect on cognitive performance after four months in mid-aged and older subjects.

Background: Low serum 25-hydroxyvitamin D (25(OH)D) levels are associated with impaired cognitive function, but the effect of vitamin D supplementation on cognitive function is uncertain.

Methods: 422 subjects were included in a randomized controlled trial with vitamin D (cholecalciferol) 100,000 IU given as a bolus dose followed by 20,000 IU per week versus placebo for four months. Cognitive function was evaluated with verbal recall test, coding test and tapping test.

Cortisol levels and cognitive profile in major depression: A comparison of currently and previously depressed patients.

The association between depressive symptoms and elevated cortisol levels, and depression and cognitive functioning, has been less robust in outpatients with symptoms in the mild to moderate range. Furthermore, the association between elevated cortisol levels and cognitive functioning is unclear. In the present study, currently depressed (n = 37), previously depressed (n = 81) and never depressed controls (n = 50) were assessed on a range of neuropsychological measures.

Failure to Find a Conditioned Placebo Analgesic Response.

Associative learning has, in several studies, been modulated by the sex of the participant. Consistent with this, a recent review found that conditioned nocebo effects are stronger in females than in males. It has been suggested that conditioned placebo responses are stronger in females, and this hypothesis was investigated in the present study.

Co-expression of 1α-hydroxylase and vitamin D receptor in human articular chondrocytes.

Background: The aim was to investigate whether resident chondrocytes in human articular cartilage and in subculture express vitamin D receptor (VDR) and the enzyme that hydroxylates the prohormone 25(OH)D to the active hormone 1α,25(OH)D, namely 1α-hydroxylase (CYP27B1). Any putative effects of vitamin D on chondrocytes were also explored.

Methods: Cartilage from human osteoarthritic knee joints, cultured chondrocytes and cells grown in 3D spheroids were examined for the expression of VDR and 1α-hydroxylase by PCR, Western blots and immunolabelling.

The role of formyl peptide receptor 1 (FPR1) in neuroblastoma tumorigenesis.

Background: Formyl peptide receptor 1 (FPR1) is a G protein-coupled receptor mainly expressed by the cells of myeloid origin, where it mediates the innate immune response to bacterial formylated peptides. High expression of FPR1 has been detected in various cancers but the function of FPR1 in tumorigenesis is poorly understood.

Methods: Expression of FPR1 in neuroblastoma cell lines and primary tumors was studied using RT-PCR, western blotting, immunofluorescence and immunohistochemistry.

Vitamin D 20,000 IU per Week for Five Years Does Not Prevent Progression From Prediabetes to Diabetes.

Context: Vitamin D deficiency is associated with insulin resistance and risk of future diabetes.

Objective: The objective of the study was to test whether supplementation with vitamin D to subjects with prediabetes will prevent progression to type 2 diabetes mellitus (T2DM).

Design: This was a randomized controlled trial performed in 2008 through 2015.

Effects of vitamin D binding protein phenotypes and vitamin D supplementation on serum total 25(OH)D and directly measured free 25(OH)D.

Objective: To determine the relationship between serum total 25-hydroxyvitamin D (25(OH)D), directly measured free 25(OH)D and calculated free 25(OH)D with regard to vitamin D-binding protein (DBP) phenotypes, sex, BMI, age and season, and their interrelationship to vitamin D supplementation.

Design, Patients And Interventions: A randomized controlled trial with 20 000 IU of vitamin D3 per week or placebo for 12 months was designed. A total of 472 subjects, 236 in each of the intervention groups, were included in the analyses.

Human articular chondrocytes express functional leukotriene B4 receptors.

Leukotriene B4 (LTB4) is a potent chemoattractant associated with the development of osteoarthritis (OA), while its receptors BLT1 and BLT2 have been found in synovium and subchondral bone. In this study, we have investigated whether these receptors are also expressed by human cartilage cells and their potential effects on cartilage cells. The expression of LTB4 receptors in native tissue and cultured cells was assessed by immunohistochemistry, immunocytochemistry, polymerase chain reaction (PCR) and electron microscopy.

No effect of high-dose vitamin D supplementation on glycemic status or cardiovascular risk factors in subjects with prediabetes.

Objective: In observational studies, low serum 25-hydroxyvitamin D [25(OH)D] concentrations have been associated with insulin resistance and other risk factors for cardiovascular disease.

Research Design And Methods: We present 1-year data from an ongoing 5-year trial in 511 individuals with impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT) randomly assigned to 20,000 IU/week vitamin D3 or placebo. An oral glucose tolerance test was performed at baseline and after 1 year.

Serum free and bio-available 25-hydroxyvitamin D correlate better with bone density than serum total 25-hydroxyvitamin D.

In the circulation 25-hydroxyvitamin D (25(OH)D) is bound to vitamin D-binding protein (DBP) and albumin. Only a small fraction is in the unbound, free form. According to the 'free-hormone-hypothesis' only the free form is biologically active.

The phosphodiesterase 8B gene rs4704397 is associated with thyroid function, risk of myocardial infarction, and body height: the Tromsø study.

Objective: High serum thyrotropin (TSH) levels predict cardiovascular disease (CVD). Recently several single nucleotide polymorphisms (SNPs) associated with TSH levels have been identified, one of them being the rs4704397 SNP in the phosphodiesterase 8B (PDE8B) gene. If the relation between thyroid function and CVD is causal, one could also expect rs4704397 genotypes to predict CVD and possibly health in general.

Serum calcium and the calcium-sensing receptor polymorphism rs17251221 in relation to coronary heart disease, type 2 diabetes, cancer and mortality: the Tromsø Study.

Serum calcium measured in 27,158 subjects in 1994 and the calcium-sensing receptor polymorphism rs17251221 genotyped in 9,404 subjects were related to cardiovascular risk factors, incident myocardial infarction (MI), type 2 diabetes (T2DM), cancer and death during follow-up until 2008-2010. In a Cox regression model with adjustment for age, gender, smoking and body mass index, subjects with serum calcium 2.50-2.

Effects of Age and Sex on Estimated Diabetes Prevalence Using Different Diagnostic Criteria: The Tromsø OGTT Study.

HbA(1c) 6.5% has recently been recommended as an alternative diagnostic criterion for diabetes. The aims of the study were to evaluate the effects of age, sex, and other factors on prevalence of diabetes and to compare risk profiles of subjects with diabetes when defined by HbA(1c) and glucose criteria.

Effect of vitamin D supplement on depression scores in people with low levels of serum 25-hydroxyvitamin D: nested case-control study and randomised clinical trial.

Aims: To compare depressive symptoms in participants with low and high serum 25-hydroxyvitamin D (25(OH)D) levels and to examine whether supplementation with vitamin D(3) would improve symptoms in those with low serum 25(OH)D levels.

Method: Participants with low 25(OH)D levels were randomised to either placebo or 40 000 IU vitamin D(3) per week for 6 months. Individuals with high serum 25(OH)D levels were used as nested controls.

Polymorphisms related to the serum 25-hydroxyvitamin D level and risk of myocardial infarction, diabetes, cancer and mortality. The Tromsø Study.

Objective: Low serum 25(OH)D levels are associated with cardiovascular risk factors, and also predict future myocardial infarction (MI), type 2 diabetes (T2DM), cancer and all-cause mortality. Recently several single nucleotide polymorphisms (SNPs) associated with serum 25-hydroxyvitamin D (25(OH)D) level have been identified. If these relations are causal one would expect a similar association between these SNPs and health.

Serum 25-hydroxyvitamin D levels in subjects with reduced glucose tolerance and type 2 diabetes - the Tromsø OGTT-study.

The relationships between vitamin D concentrations, hyperglycemia, and insulin resistance remain uncertain. During 2008 - 2010, an oral glucose tolerance test was performed in 3520 subjects from Tromsø, Norway. Serum 25-hydroxyvitamin D [25(OH)D] was measured in 1193 subjects with normal glucose tolerance, in 304 with isolated impaired fasting glucose, in 254 with isolated impaired glucose tolerance, in 139 with a combination of the two, and in 194 subjects with type 2 diabetes.

Staphylococcus epidermidis polysaccharide intercellular adhesin activates complement.

Staphylococcus epidermidis is a frequent cause of nosocomial infections. The central virulence factor of S. epidermidis is biofilm formation.

Vitamin D, insulin secretion, sensitivity, and lipids: results from a case-control study and a randomized controlled trial using hyperglycemic clamp technique.

Objective: Vitamin D deficiency is associated with an unfavorable metabolic profile in observational studies. The intention was to compare insulin sensitivity (the primary end point) and secretion and lipids in subjects with low and high serum 25(OH)D (25-hydroxyvitamin D) levels and to assess the effect of vitamin D supplementation on the same outcomes among the participants with low serum 25(OH)D levels.

Research Design And Methods: Participants were recruited from a population-based study (the Tromsø Study) based on their serum 25(OH)D measurements.

Differences in serum levels of CB-153 and p,p'-DDE, and reproductive parameters between men living south and north in Norway.

Arctic is contaminated with persistent organochlorine pollutants (POPs), and exposure to these compounds may differ between south and north in Norway. POPs may have negative impact on male reproductive characteristics. We compared serum levels of the CB-153 and p,p'-DDE in men who were born and had lived most of their lifetime south and north (close to or above the Arctic Circle) in Norway.

Variation of serum creatine kinase (CK) levels and prevalence of persistent hyperCKemia in a Norwegian normal population. The Tromsø Study.

In this cross-sectional study we assessed the prevalence of hyperCKemia, defined as persistent CK values ≥210 U/L in women, ≥400 U/L in men <50 years and ≥280 U/L in men ≥50 years (reference values according to the Nordic Reference Interval Project). Blood samples were obtained from 12,828 participants in the 6th survey of The Tromsø Study. We identified 686 (5.

Serum 25-hydroxyvitamin D levels are inversely associated with glycated haemoglobin (HbA(1c)). The Tromsø Study.

Animal and human studies have shown an association between serum 25-hydroxyvitamin D (25(OH)D) level and insulin secretion and sensitivity. Accordingly, an association between 25(OH)D and glycated haemoglobin (HbA(1c)) is to be expected, and this was tested for in the present study. The Tromsø Study is a longitudinal population-based study initiated in 1974.

Human articular chondrocytes express ChemR23 and chemerin; ChemR23 promotes inflammatory signalling upon binding the ligand chemerin(21-157).

Introduction: Chemerin is a chemotactic peptide which directs leukocytes expressing the chemokine-like receptor ChemR23 towards sites of inflammation. ChemR23 is a G protein-coupled receptor which binds several different ligands, and it is also expressed by other cell types such as adipocytes. In addition to chemotaxis, recent reports suggest that ChemR23 is capable of mediating either inflammatory or anti-inflammatory effects, depending on the type of ligand it binds.

The secretory profiles of cultured human articular chondrocytes and mesenchymal stem cells: implications for autologous cell transplantation strategies.

This study was undertaken to compare the phenotype of human articular chondrocytes (ACs) and bone marrow-derived mesenchymal stem cells (MSCs) after cell expansion by studying the spectrum of proteins secreted by cells into the culture medium. ACs and MSCs were expanded in monolayer cultures for some weeks, as done in standard cell transplantation procedures. Initially, the expression of cartilage signature genes was compared by real-time PCR.

Effect of smoking on the serum levels of 25-hydroxyvitamin D depends on the assay employed.

Objective: Because we found higher serum 25-hydroxyvitamin D (25(OH)D) levels among smokers than among non-smokers with analyses using an electrochemiluminescence immunoassay (ECLIA) from Roche, the purpose of the present study was to examine whether this difference between smokers and non-smokers was maintained using other serum 25(OH)D assays.

Design: A cross-sectional population-based study on 6932 participants from the Tromsø study, 1994-1995, and one validation study comparing six different serum 25(OH)D assays in 53 non-smokers and 54 smokers were performed.

Methods: The association between smoking, season and serum 25(OH)D as measured by ECLIA (Roche) was assessed in the population-based study using general linear models with multivariate adjustments.