PCB-126 spiked to polyethylene microplastic ingested by juvenile Atlantic cod (Gadus morhua) accumulates in liver and muscle tissues

In the present study, polyethylene (PE) microplastics (150–300 μm) were added to Atlantic cod (Gadus morhua) feeds at 1 %, either in their present form (Virgin PE) or spiked with PCB-126 (Spiked PE). The feeds were given to juvenile cod for a 4-week period. The fish grew from 11 to 23 g with no significant difference between dietary treatments. Cod fed spiked PE showed a significantly higher concentration of PCB-126 in liver and muscle samples compared to control and fish ingesting virgin PE. In accordance with the accumulation of PCB-126 in the liver, the expression of hepatic cyp1a was higher in cod fed spiked PE. Notably, we observed that spiked PE, as well as virgin PE, have an effect on skin. Overall changes indicated a reduced skin barrier in fish fed a diet containing PE. Indicating that PE itself through interaction with gut tissue may influence skin health in fish.PCB-126 spiked to polyethylene microplastic ingested by juvenile Atlantic cod (Gadus morhua) accumulates in liver and muscle tissuespublishedVersio

References for ultrasound staging of breast maturation, tanner breast staging, pubic hair, and menarche in Norwegian girls

Context - Discriminating adipose and glandular tissue is challenging when clinically assessing breast development. Ultrasound facilitates staging of pubertal breast maturation (US B), but has not been systematically compared to Tanner breast (Tanner B) staging, and no normative data have been reported. Objective - To present normative references for US B along with references for Tanner B, pubic hair (PH), and menarche. Design, Setting, and Participants - A cross-sectional sample of 703 healthy girls aged 6 to 16 years were examined. Main Outcome Measures - Breast development was determined with US B and Tanner B staging. Tanner PH and menarcheal status were recorded. The age distributions of entry in US B, Tanner B, and PH stages and menarche were estimated with generalized linear and generalized additive models with a probit link. Method agreement was tested with weighted Cohen’s kappa. Results - The median (±2SD) ages for thelarche, US B2 and Tanner B2, were 10.2 (7.7, 12.8) and 10.4 (8.0, 12.7) years. The median (±2SD) ages at Tanner PH2 and menarche were 10.9 (8.5, 13.3) and 12.7 (11.0, 16.2) years. Cohen’s kappa of agreement (95% confidence interval) between US B and Tanner B was 0.87 (0.85–0.88). When the methods disagreed, US B was usually more advanced. Conclusion - Thelarche occurred at a slightly younger age when assessed with ultrasound compared to clinical Tanner staging, although the 2 methods had a very good agreement when determining pubertal breast maturation. A significant decrease of 2.8 months in age at menarche was observed during the past decade in Norwegian girls

Socio-economic status and menarcheal age in urban african schoolgirls in the western cape, South Africa

The impact of different socio-economic levels, height, weight and sum of four skinfolds on the menarcheal age of 302 Black, South African school girls ranging in age from 8 to 17 years was researched. Socioeconomic status was obtained by means of a questionnaire that focused on the education, income, and occupations of the parents of the participants and the accommodation in which they were reared. Menarcheal age was obtained by means of a questionnaire. When restricted to those girls who had reached menarche, the mean age was found to be 14.34 years (SD=0.93). The application of survival analysis revealed an estimated median age of 14.25 years with a 95% confidence interval estimate of 14.08 and 14.58. Based on the log-rank statistic, significant differences were found in the survival curves of the different SES categories (p=0.0098). It was found that lower SES corresponded to curves having longer survival times, i.e. later ages of menarche. Differences were found in weight (p=0.037) and in height (p=0.0042), but no difference in SUM4 (p=0.44), between girls who have reached menarche and those who have not.DHE

On the Distance to the Ophiuchus Star-Forming Region

The Ophiuchus molecular cloud complex has produced in Lynds 1688 the richest known embedded cluster within ~300 pc of the Sun. Unfortunately, distance estimates to the Oph complex vary by nearly ~40% (~120-165 pc). Here I calculate a new independent distance estimate of 135 +- 8 pc to this benchmark star-forming region based on Hipparcos trigonometric parallaxes to stars illuminating reflection nebulosity in close proximity to Lynds 1688. Combining this value with recent distance estimates from reddening studies suggests a consensus distance of 139 +- 6 pc (4% error), situating it within ~11 pc of the centroid of the ~5 Myr old Upper Sco OB subgroup of Sco OB2 (145 pc). The velocity vectors for Oph and Upper Sco are statistically indistinguishable within ~1 km/s in each vector component. Both Oph and Upper Sco have negligible motion (<1 km/s) in the Galactic vertical direction with respect to the Local Standard of Rest, which is inconsistent with the young stellar groups having formed via the high velocity cloud impact scenario.Comment: to appear in Jan 2008 AN (5 pages), note added in proof regarding new distance estimate (131+-3 pc) using revised Hipparcos parallaxe

Maternal PCOS status and metformin in pregnancy: Steroid hormones in 5–10 years old children from the PregMet randomized controlled study

Objective: Polycystic ovary syndrome (PCOS) is a common endocrine disorder, with potential effects on offspring both genetically and through altered intrauterine environment. Metformin, which ameliorate hormonal disturbances in non-pregnant women with PCOS is increasingly used in pregnancy. It passes the placenta, and the evidence on potential consequences for offspring endocrine development is scarce. We explore the potential effects of maternal PCOS status and intrauterine metformin exposure on offspring steroid hormone levels. Design: This is a follow-up study of 5–10 years old children from the PregMet-study–a randomized controlled trial comparing metformin (2000 mg/day) to placebo during PCOS pregnancies. Of the 255 children invited, 117 (46%) were included. Methods: There was no intervention in this follow-up study. Outcomes were serum levels of androstenedione, testosterone, SHBG, cortisol, 17-hydroxyprogesterone, 11-deoxycortisol and calculated free testosterone converted to gender-and age adjusted z-scores from a Norwegian reference population. These were compared in i) placebo-exposed children versus children from the reference population (z-score zero) by the deviation in z-score by one-sample t-tests and ii) metformin versus placebo-exposed children by two-sample t-tests. Holm-Bonferroni adjustments were performed to account for multiple endpoints. Results: Girls of mothers with PCOS (n = 30) had higher mean z-scores of androstenedione (0.73 (95% confidence interval (CI) 0.41 to 1.06), p<0.0001), testosterone (0.76 (0.51 to 1.00), p<0.0001), and free testosterone (0.99 (0.67 to 1.32), p<0.0001) than the reference population. Metformin-exposed boys (n = 31) tended to have higher 11-deoxycortisol z-score than placebo-exposed boys (n = 24) (mean difference 0.65 (95% CI 0.14–1.17), p = 0.014). Conclusion: Maternal PCOS status was associated with elevated androgens in 5- to 10-year-old daughters, which might indicate earlier maturation and increased risk of developing PCOS. An impact of metformin in pregnancy on steroidogenesis in children born to mothers with PCOS cannot be excluded. Our findings need confirmation in studies that include participants that have entered puberty.publishedVersio

AVACircuitos - Ambiente Virtual de Análise de Circuitos

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Testicular ultrasound to stratify hormone references in a cross-sectional Norwegian study of male puberty

Context: Testicular growth represents the best clinical variable to evaluate male puberty, but current pediatric hormone references are based on chronological age and subjective assessments of discrete puberty development stages. Determination of testicular volume (TV) by ultrasound provides a novel approach to assess puberty progression and stratify hormone reference intervals. Objective: The objective of this article is to establish references for serum testosterone and key hormones of the male pituitary-gonadal signaling pathway in relation to TV determined by ultrasound. Design, Setting, and Participants: Blood samples from 414 healthy Norwegian boys between ages 6 and 16 years were included from the cross-sectional “Bergen Growth Study 2.” Participants underwent testicular ultrasound and clinical assessments, and serum samples were analyzed by liquid chromatography tandem–mass spectrometry and immunoassays. Main Outcome Measures: We present references for circulating levels of total testosterone, luteinizing hormone, follicle-stimulating hormone, and sex hormone–binding globulin in relation to TV, chronological age, and Tanner pubic hair stages. Results: In pubertal boys, TV accounted for more variance in serum testosterone levels than chronological age (Spearman r = 0.753, P < .001 vs r = 0.692, P < .001, respectively). Continuous centile references demonstrate the association between TV and hormone levels during puberty. Hormone reference intervals were stratified by TV during the pubertal transition. Conclusions: Objective ultrasound assessments of TV and stratification of hormone references increase the diagnostic value of traditional references based on chronological age or subjective staging of male puberty.acceptedVersio

Hormone references for ultrasound breast staging and endocrine profiling to detect female onset of puberty

Context - Application of ultrasound (US) to evaluate attainment and morphology of glandular tissue provides a new rationale for evaluating onset and progression of female puberty, but currently no hormone references complement this method. Furthermore, previous studies have not explored the predictive value of endocrine profiling to determine female puberty onset. Objective - To integrate US breast staging with hypothalamic-pituitary-gonadal hormone references and test the predictive value of an endocrine profile to determine thelarche. Design Setting and Participants - Cross-sectional sample of 601 healthy Norwegian girls, ages 6 to 16 years. Main Outcome Measures - Clinical and ultrasound breast evaluations were performed for all included girls. Blood samples were analyzed by immunoassay and ultrasensitive liquid chromatography–tandem mass spectrometry (LC-MS/MS) to quantify estradiol (E2) and estrone (E1) from the subpicomolar range. Results - References for E2, E1, luteinizing hormone, follicle-stimulating hormone, and sex hormone–binding globulin were constructed in relation to chronological age, Tanner stages, and US breast stages. An endocrine profile index score derived from principal component analysis of these analytes was a better marker of puberty onset than age or any individual hormone, with receiver-operating characteristic area under the curve 0.91 (P < 0.001). Ultrasound detection of nonpalpable glandular tissue in 14 out of 264 (5.3%) girls with clinically prepubertal presentation was associated with significantly higher median serum levels of E2 (12.5 vs 4.9 pmol/L; P < 0.05) and a distinct endocrine profile (arbitrary units; P < 0.001). Conclusions - We provide the first hormone references for use with US breast staging and demonstrate the application of endocrine profiling to improve detection of female puberty onset