Decoupling of paramagnetic and ferrimagnetic AMS development during the experimental chemical compaction of illite shale powder

Inclination shallowing of detrital remanent magnetization in sedimentary strata has solely been constrained for the mechanical processes associated with mud deposition and shallow compaction of clay-rich sediment, even though a significant part of mud diagenesis involves chemical compaction. Here we report, for the first time, on the laboratory simulation of magnetic assemblage development in a chemically compacting illite shale powder of natural origin. The experimental procedure comprised three compaction stages that, when combined, simulate the diagenesis and low-grade metamorphism of illite mud. First, the full extent of load-sensitive mechanical compaction is simulated by room temperature dry axial compression. Subsequently, temperature controlled chemical compaction is initiated by exposing the sample in two stages to amphibolite or granulite facies conditions (temperature is 490 to 750°C and confining pressure is 170 or 300 MPa) both in the absence (confining pressure only) and presence of a deformation stress field (axial compression or confined torsion). Thermodynamic equilibrium in the last two compaction stages was not reached, but illite and mica dehydroxylation initiated, thus providing a wet environment. Magnetic properties were characterized by magnetic susceptibility and its anisotropy (AMS) in both high- and low-applied field. Acquisition of isothermal remanent magnetization (IRM), stepwise three-component thermal de-magnetization of IRM and first-order reversal curves were used to characterize the remanence-bearing minerals. During the chemical compaction experiments ferrimagnetic iron-sulphides formed after reduction of magnetite and detrital pyrite in a low sulphur fugacity environment. The degree of low-field AMS is unaffected by porosity reduction from 15 to ∼1 per cent, regardless of operating conditions and compaction history. High-field paramagnetic AMS increases with compaction for all employed stress regimes and conditions, and is attributed to illite transformation to iron-bearing mica. AMS of authigenic iron-sulphide minerals remained constant during compaction indicating an independence of ferrimagnetic fabric development to chemical compaction in illite shale powder. The decoupling of paramagnetic and ferrimagnetic AMS development during chemical compaction of pelite contrasts with findings from mechanical compaction studie

Hypospadias as a novel feature in spinal bulbar muscle atrophy

Spinal and bulbar muscle atrophy (SBMA) is an X-linked neuromuscular disorder caused by CAG repeat expansions in the androgen receptor (AR) gene. The SBMA phenotype consists of slowly progressive neuromuscular symptoms and undermasculinization features as the result of malfunction of the AR. The latter mainly includes gynecomastia and infertility. Hypospadias is also a feature of undermasculinization with an underdeveloped urethra and penis; it has not been described as part of the SBMA phenotype but has been suggested to be associated with a prolonged CAG repeat in the AR gene. This study includes the first epidemiologic description of the co-occurrence of hypospadias and SBMA in subjects and their male relatives in Swedish population-based health registers, as well as an additional clinical case. One boy with severe hypospadias was screened for mutations in the AR gene and was found to have 42 CAG repeats in it, which is in the full range of mutations causing SBMA later in life. We also detected a maximum of four cases displaying the combination of SBMA and hypospadias in our national register databases. This is the third case report with hypospadias in association with CAG repeat expansions in the AR gene in the full range known to cause SBMA later in life. Our findings suggest that hypospadias may be an under diagnosed feature of the SBMA phenotype and we propose that neurologists working with SBMA further investigate and report the true prevalence of hypospadias among patients with SBMA.Swedish Research Council, K2012-64X-14506-10-5Stockholm City CouncilFoundation Frimurare Barnhuset in StockholmSwedish Research Council through the Swedish Initiative for Research on Microdata in the Social And Medical Sciences (SIMSAM), 340-2013-5867Accepte

Nationwide population-based cohort study of psychiatric disorders in individuals with Ehlers-Danlos syndrome or hypermobility syndrome and their siblings

Background: To assess the risk of psychiatric disorders in Ehlers-Danlos syndrome (EDS) and hypermobility syndrome. Methods: Nationwide population-based matched cohort study. EDS, hypermobility syndrome and psychiatric disorders were identified through Swedish national registries. Individuals with EDS (n = 1,771) were matched with comparison individuals (n = 17,710). Further, siblings to individuals with EDS who did not have an EDS diagnosis themselves were compared with matched comparison siblings. Using conditional logistic regression, risk of autism spectrum disorder (ASD), bipolar disorder, attention deficit hyperactivity disorder (ADHD), depression, attempted suicide, suicide and schizophrenia were estimated. The same analyses were conducted in individuals with hypermobility syndrome (n = 10,019) and their siblings. Results: EDS was associated with ASD: risk ratio (RR) 7.4, 95 % confidence interval (95 % CI) 5.2–10.7; bipolar disorder: RR 2.7, CI 1.5–4.7; ADHD: RR 5.6, CI 4.2–7.4; depression: RR 3.4, 95 % CI 2.9–4.1; and attempted suicide: RR 2.1, 95 % CI 1. 7–2.7, but not with suicide or schizophrenia. EDS siblings were at increased risk of ADHD: RR 2.1, 95 % CI 1.4–3.3; depression: RR 1.5, 95 % CI 1.1–1.8; and suicide attempt: RR 1.8, 95 % CI 1.4–2.3. Similar results were observed for individuals with hypermobility syndrome and their siblings. Conclusions: Individuals with EDS and hypermobility syndrome are at increased risks of being diagnosed with psychiatric disorders. These risk increases may have a genetic and/or early environmental background as suggested by evidence showing that siblings to patients have elevated risks of certain psychiatric disorders.NonePublishe

Association between parental age and asthma in a population-based register study

In a nationwide population-based study with family design, we found an association between decreasing parental age and asthma in early childhood. The effect was independent of familial and potentially confounding factors.NoneAccepte

Infant and early childhood dietary predictors of overweight at age 8 years in the CAPS population

BACKGROUND/OBJECTIVES: Programs to address obesity are a high priority for public policy especially for young children. Research into dietary determinants of obesity is challenging but important for rational planning of interventions to prevent obesity, given that both diet and energy expenditure influence weight status. We investigated whether early life dietary factors were predictive of weight status at 8 years in a cohort of Australian children. SUBJECTS/METHODS: We used data from the Childhood Asthma Prevention Study-a birth cohort at high risk of asthma. Dietary data (3-day weighed food records) were collected at 18 months and height, weight and waist circumference were collected at 8 years. We assessed the relationship between dietary predictor variables and measures of adiposity using linear regression. RESULTS: Intakes of protein, meat and fruit at age 18 months were positively associated with measures of adiposity at age 8 years, namely, body mass index and/or waist circumference. We also showed a significant negative relationship between these measures of adiposity at 8 years and intake at 18 months of dairy foods as a percent of total energy, and intake of energy dense cereal-based foods such as cookies and crackers. CONCLUSIONS: This birth cohort study with rigorous design, measures and analyses, has shown a number of associations between early dietary intake and subsequent adiposity that contribute to the growing evidence base in this important field.National Health and Medical Research Council of AustraliaHjärt- och LungfondenSvenska LäkarsällskapetManuscrip

Birth weight as an independent predictor of ADHD symptoms : a within-twin pair analysis

BACKGROUND: Studies have found an association between low birth weight and ADHD, but the nature of this relation is unclear. First, it is uncertain whether birth weight is associated with both of the ADHD dimensions, inattentiveness and hyperactivity-impulsivity. Second, it remains uncertain whether the association between birth weight and ADHD symptom severity is confounded by familial factors. METHOD: Parents of all Swedish 9- and 12-year-old twins born between 1992 and 2000 were interviewed for DSM-IV inattentive and hyperactive-impulsive ADHD symptoms by the Autism - Tics, AD/HD and other Comorbidities (A-TAC) inventory (N= 21,775 twins). Birth weight was collected prospectively through the Medical Birth Registry. We used a within-twin pair design to control for genetic and shared environmental factors. RESULTS: Reduced birth weight was significantly associated with a mean increase in total ADHD (beta = -.42; 95% CI: -.53, -.30), inattentive (beta = -.26; 95% CI: -.33, -.19), and hyperactive-impulsive (beta = -.16; 95% CI: -.22, -.10) symptom severity. These results imply that a change of one kilogram of birth weight corresponded to parents rating their child nearly one unit higher (going from "no" to "yes, to some extent" on a given symptom) on the total ADHD scale. These associations remained within pairs of MZ and DZ twins, and were also present when restricting the analyses to full term births. CONCLUSIONS: There is an independent association between low birth weight and all forms of ADHD symptoms, even after controlling for all environmental and genetic confounds shared within twin pairs. These results indicate that fetal growth restriction (as reflected in birth weight differences within twin pairs) and/or the environmental factors which influence it is in the casual pathway leading to ADHD.The Swedish Council for Working Life and Social ResearchThe Swedish Research CouncilManuscrip

Allergen-specific IgE over time in women before, during and after pregnancy

The trajectory of IgE levels before, during and after pregnancy in sensitized individuals is characterized by significant increase in specific IgE to birch allergens but not to other allergens after multiple testing. This increase may warrant some surveillance in the antenatal care for those with clinical symptoms.The Swedish Research CouncilThe Swedish initiative for Research on Microdata in the Social And Medical Sciences (SIMSAM) framework grant no 340-2013-5867Stockholm County Council (ALF-projects)The Strategic Research Program in Epidemiology at Karolinska InstitutetDepartment of Clinical Sciences at Danderyd HospitalSwedish Medical Research CouncilSwedish Heart-Lung FoundationSwedish Asthma and Allergy Association’s Research FoundationAccepte

Limited association between markers of stress during pregnancy and fetal growth in “Born into Life”, a new prospective birth cohort

AIMS: We aimed to investigate the associations between perceived maternal stress or salivary cortisol levels during pregnancy and birth weight. METHODS: In 2010-2012 we recruited 92 women living in Stockholm, Sweden, and followed them from before conception and through pregnancy and childbirth. Their Perceived Stress Scale (PSS) scores and salivary cortisol levels were collected at 26-28 gestational weeks. Birth weight was collected from medical records. Linear regression analyses and Pearson correlations were performed between the PSS scores or cortisol levels and birth weight respectively, adjusted for gestational age. RESULTS: No significant associations were found between PSS scores or cortisol levels and birth weight. There was a trend towards higher salivary cortisol levels among infants with lower birth weights and this effect was attenuated after adjusting for gestational age. Morning cortisol levels (r=-0.31, p=0.01), the decline in cortisol levels (r=-0.26, p=0.03) and evening cortisol levels (r=-0.21, p=0.09) were negatively correlated with PSS scores. CONCLUSION: Maternal stress during pregnancy was not associated to birth weight. The inverse correlation between PSS scores and cortisol levels may indicate other mechanisms for maternal stress on child outcomes than the previous explanation of hypothalamic-pituitary-adrenal axis activity.Swedish Initiative for Research on Microdata in the Social and Medical Sciences (SIMSAM) framework grant no 340-2013-5867, as well as the Swedish Heart Lung Foundation, the Swedish Asthma and Allergy Association’s Research Foundation, grants provided by the Stockholm County Council (ALF project), FORTE, and the Strategic Research Program in Epidemiology at Karolinska Institutet.Accepte

Limited association between markers of stress during pregnancy and fetal growth in 'Born into Life' : a new prospective birth cohort

Aims: We aimed to investigate the associations between perceived maternal stress or salivary cortisol levels during pregnancy and birthweight. Methods: In 2010-2012, we recruited 92 women living in Stockholm, Sweden, and followed them from before conception and through pregnancy and childbirth. Their Perceived Stress Scale (PSS) scores and salivary cortisol levels were collected at 26-28 gestational weeks. Birthweight was collected from medical records. Linear regression analyses and Pearson correlations were performed between the PSS scores or cortisol levels and birthweight, respectively, adjusted for gestational age. Results: No significant associations were found between PSS scores or cortisol levels and birthweight. There was a trend towards higher salivary cortisol levels among infants with lower birthweights, and this effect was attenuated after adjusting for gestational age. Morning cortisol levels (r = -0.31, p = 0.01), the decline in cortisol levels (r = -0.26, p = 0.03) and evening cortisol levels (r = -0.21, p = 0.09) were negatively correlated with PSS scores. Conclusion: Maternal stress during pregnancy was not associated with birthweight. The inverse correlation between PSS scores and cortisol levels may indicate other mechanisms for maternal stress on child outcomes than the previous explanation of hypothalamic-pituitary-adrenal axis activity.Swedish Research CouncilSwedish Initiative for Research on Microdata in the Social and Medical Sciences framework (grant no 340-2013-5867)Swedish Heart Lung FoundationSwedish Asthma and Allergy Association's Research FoundationStockholm County Council ALF-projectsFORTEFORMASStrategic Research Program in Epidemiology at Karolinska InstitutetAccepte

Individual maternal and child exposure to antibiotics in hospital : a national population-based validation study

Aim: Exposure to antibiotics in early life may affect future health. Most antibiotics are prescribed in outpatient care, but inpatient exposure is also important. We estimated how specific diagnoses in hospitals corresponded to individual antibiotic exposure. Methods: All pregnant women and children from birth to five-years-of-age with infectious diseases and common inpatient diagnoses between July 2005 and November 2011were identified from the Swedish National Patient Register. Random samples of individuals from pre-defined groups were drawn and medical records received from the clinics were manually reviewed for antibiotics. Results: Medical records for 4,319 hospital visits were requested and 3,797 (88%) were received. A quarter (25%) of children diagnosed as premature had received antibiotics and in children from one to five-years-of-age, diagnoses associated with bacterial infections were more commonly treated with antibiotics (62.4-90.6%) than those associated with viruses (6.3-22.2%). Pregnant women who had undergone a Caesarean section were more likely to be treated with antibiotics than those who had had a vaginal delivery (40.1% versus 11.1%). Conclusions: This study defines the proportion of new mothers and young children who received individual antibiotic treatment for specific inpatient diagnoses in Sweden and provides a useful basis for future studies focusing on antibiotic use.Swedish Research Council, 2011-3060Swedish Initiative for Research on Microdata in the Social And Medical Sciences (SIMSAM), 80748301 and 340-2013- 5867Stockholm County Council (ALF)Swedish Heart Lung FoundationStrategic Research Program in Epidemiology at Karolinska InstitutetManuscrip