Physiological and Behavioral Effects of Salt Stress on Juvenile American Alligators (Alligator mississippiensis)

American alligators (Alligator mississippiensis) inhabit freshwater wetlands but are vulnerable to salt stress during storm surges and droughts. Anthropogenic alterations to freshwater system hydrology, runoff of coal mine spoils, and road de-icing using salt can further contribute to salinization of freshwater habitats. Juvenile alligators are especially vulnerable to salt stress due to their thinner integument and lower mobility and ability to avoid saltwater. Little is known about how crocodilian physiological systems respond to environmental stressors such as salinity. To better understand the effects of saltwater on alligators, juvenile alligators were exposed to 12‰ saltwater for 5-week and 1-week periods and blood plasma biochemistry, components of the renin-angiotensin-aldosterone system, steroidogenesis, and behavior were assessed. Furthermore, to correlate findings in laboratory-based studies with conditions in the wild, juvenile male and female wild alligators in various salinities were opportunistically sampled each month excluding November, December, and January for one year at Rockefeller Wildlife Refuge in coastal Louisiana. Compared to freshwater-kept alligators, 5-week exposure to 12‰ saltwater significantly elevated plasma corticosterone, 11-deoxycortisol, 17α-hydroxyprogesterone, testosterone, estrone, 17β-estradiol, and estriol. Conversely, alligators exposed to 12‰ saltwater for 1 week had significantly reduced estrone and 17β-estradiol, while corticosterone and 11-deoxycortisol were elevated and histology showed alterations in gonad tissues. Additionally, the progestogen 17α,20β-dihydroxypregnenone was significantly, positively correlated with environmental salinities wild juvenile male alligators were found in. Angiotensin II was significantly reduced after 5- and 1-week exposure, which correlated with low renin and angiotensin-converting enzyme expression in kidney and lung tissues of alligators exposed for 1 week. Na+ and Cl- were significantly elevated after 5- and 1-week exposure, which corresponded well with Na+ and Cl- being strongly, positively correlated with environmental salinities wild juvenile male alligators were found in. Additionally, saltwater-exposed alligators largely ceased feeding within 1 week and spent significantly less time basking compared with pre-salinity observations. This dissertation demonstrates behavioral changes and time-dependent, dynamic changes in physiology of juvenile alligator exposed to saltwater. This work further shows significant correlation of environmental salinity with electrolyte levels and a sex steroid in wild juvenile alligators, and to my knowledge represents the first measurement of 17α,20β-dihydroxypregnenone in alligators

Higher independent mobility to school among adolescents: A secondary analysis using cross-sectional data between 2010 and 2017 in Spanish youth

The PACO Study was supported by the Spanish Ministry of Economy, Industry and Competitiveness and the European Regional Development Fund (DEP2016-75598-R, MINECO/FEDER, UE), and Spanish Ministry of Education and Vocational Training (FPU17/03934). This study has been partially funded by the University of Granada, Plan Propio de Investigación 2016, Excellence actions: Units of Excellence; Unit of Excellence on Exercise and Health (UCEES), and by the Junta de Andalucía, Consejería de Conocimiento, Investigación y Universidades, European Regional Development Fund (ERDF), ref. SOMM17/6107/UGR. This study is part of a PhD thesis conducted in the Official Doctoral Program in Biomedicine of the University of Granada, SpainThe team would like to acknowledge the support of the following Spanish research centres and local/regional public institutions in providing data used in this study: Auguria, Agenda 21, University of Cádiz, University of Valencia, Autonomous University of Barcelona, University of Zaragoza, La Biciclante, La Ciclería, City Council of Zaragoza, University Carlos III and University of Granada.Aim: To describe and to analyse the associations between independent mobility to school (IM) with gender and age in Spanish youth aged 6–18 years old from 2010 to 2017. Moreover, to study the changes in the rates of IM from 2010 to 2017 by gender and age. Methods: Cross-sectional data were obtained from 11 Spanish studies. The study sample comprised 3460 children and 1523 adolescents. Logistic regressions models (IM with gender and age) and multilevel logistic regressions (IM with time period) were used. Results: Boys had higher odds ratio (OR) of IM than girls in children (OR = 1.86; CI: 1.50–2.28, p < 0.01). Adolescents showed higher IM than children: 12–14 years old (OR: 6.30; CI: 1.65–23.97) and 14–16 years old (OR: 7.33; CI: 1.18–45.39) had higher IM than 6–8 years old for boys (all, p < 0.05). Moreover, 12–14 years old (OR: 4.23; CI: 1.01–17.81) had higher IM than 6–8 years old for girls (p < 0.001). IM was not associ- ated with the time period. Conclusion: The IM is higher in boys and in adolescents, highlighting the relevance to promote IM strategies targeting girls and children. In these strategies is essential the support of researchers, public health practitioners and families to achieve positive results.Spanish Ministry of Economy, Industry and Competitiveness and the European Regional Development Fund, Grant/Award Number: DEP2016-75598-RSpanish Ministry of Education and Vocational Training, Grant/Award Number: FPU17/03934Funding for open access charge: Universidad de Granada / CBU

Evidence for L1-associated DNA rearrangements and negligible L1 retrotransposition in glioblastoma multiforme

Background: LINE-1 (L1) retrotransposons are a notable endogenous source of mutagenesis in mammals. Notably, cancer cells can support unusual L1 retrotransposition and L1-associated sequence rearrangement mechanisms following DNA damage. Recent reports suggest that L1 is mobile in epithelial tumours and neural cells but, paradoxically, not in brain cancers. Results: Here, using retrotransposon capture sequencing (RC-seq), we surveyed L1 mutations in 14 tumours classified as glioblastoma multiforme (GBM) or as a lower grade glioma. In four GBM tumours, we characterised one probable endonuclease-independent L1 insertion, two L1-associated rearrangements and one likely Alu-Alu recombination event adjacent to an L1. These mutations included PCR validated intronic events in MeCP2 and EGFR. Despite sequencing L1 integration sites at up to 250× depth by RC-seq, we found no tumour-specific, endonuclease-dependent L1 insertions. Whole genome sequencing analysis of the tumours carrying the MeCP2 and EGFR L1 mutations also revealed no endonuclease-dependent L1 insertions. In a complementary in vitro assay, wild-type and endonuclease mutant L1 reporter constructs each mobilised very inefficiently in four cultured GBM cell lines. Conclusions: These experiments altogether highlight the consistent absence of canonical L1 retrotransposition in GBM tumours and cultured cell lines, as well as atypical L1-associated sequence rearrangements following DNA damage in vivo

BRAF Fusion Analysis in Pilocytic Astrocytomas: KIAA1549-BRAF 15-9 Fusions Are More Frequent in the Midline Than Within the Cerebellum

Copyright © 2015 by the American Association of Neuropathologists, Inc. Pilocytic astrocytomas (PAs) are increasingly tested for KIAA1549-BRAF fusions. We used reverse transcription polymerase chain reaction for the 3 most common KIAA1549-BRAF fusions, together with BRAF V600E and histone H3.3 K27M analyses to identify relationships of these molecular characteristics with clinical features in a cohort of 32 PA patients. In this group, the overall BRAF fusion detection rate was 24 (75%). Ten (42%) of the 24 had the 16-9 fusion, 8 (33%) had only the 15-9 fusion, and 1 (4%) of the patients had only the 16-11 fusion. In the PAs with only the 15-9 fusion, 1 PA was in the cerebellum and 7 were centered in the midline outside of the cerebellum, that is, in the hypothalamus (n = 4), optic pathways (n = 2), and brainstem (n = 1). Tumors within the cerebellum were negatively associated with fusion 15-9. Seven (22%) of the 32 patients had tumor-related deaths and 25 of the patients (78%) were alive between 2 and 14 years after initial biopsy. Age, sex, tumor location, 16-9 fusion, and 15-9 fusion were not associated with overall survival. Thus, in this small cohort, 15-9 KIAA1549-BRAF fusion was associated with midline PAs located outside of the cerebellum; these tumors, which are generally difficult to resect, are prone to recurrence

Adiposity in preadolescent children: Associations with cardiorespiratory fitness

Lifestyle factors contribute to childhood obesity risk, however it is unclear which lifestyle factors are most strongly associated with childhood obesity. The purpose of this cross-sectional study was to simultaneously investigate the associations among dietary patterns, activity behaviors, and physical fitness with adiposity (body fat %, fat mass, body mass index [BMI], and waist to hip ratio) in preadolescent children. Preadolescent children (N = 392, 50% female, age: 9.5 ± 1.1year, BMI: 17.9 ± 3.3 kg/m2) were recruited. Body fat (%) and fat mass (kg) were measured with bioelectrical impedance analysis. Cardiorespiratory fitness (VO2 max), muscular strength (hand-grip strength), activity, sleep, and dietary pattern was assessed. Multivariable analysis revealed that cardiorespiratory fitness associated most strongly with all four indicators of adiposity (body fat (%) (β = -0.2; p < .001), fat mass (β = -0.2; p < .001), BMI (β = -0.1; p < .001) and waist to hip ratio (β = -0.2; p < .001). Additionally, fruit and vegetable consumption patterns were associated with body fat percentage, but the association was negligible (β = 0.1; p = 0.015). Therefore, future interventions should aim to promote the use of cardiorespiratory fitness as a means of reducing the obesity epidemic in children

SIOP‐PODC adapted risk stratification and treatment guidelines: Recommendations for neuroblastoma in low‐ and middle‐income settings

Neuroblastoma is the most common extracranial solid tumor in childhood in high‐income countries (HIC), where consistent treatment approaches based on clinical and tumor biological risk stratification have steadily improved outcomes. However, in low‐ and middle‐ income countries (LMIC), suboptimal diagnosis, risk stratification, and treatment may occur due to limited resources and unavailable infrastructure. The clinical practice guidelines outlined in this manuscript are based on current published evidence and expert opinions. Standard risk stratification and treatment explicitly adapted to graduated resource settings can improve outcomes for children with neuroblastoma by reducing preventable toxic death and relapse. Pediatr Blood Cancer 2015;62:1305–1316. © 2015 The Authors. Pediatric Blood & Cancer, published by Wiley Periodicals, Inc

LINE-1 Evasion of Epigenetic Repression in Humans

Epigenetic silencing defends against LINE-1 (L1) retrotransposition in mammalian cells. However, the mechanisms that repress young L1 families and how L1 escapes to cause somatic genome mosaicism in the brain remain unclear. Here we report that a conserved Yin Yang 1 (YY1) transcription factor binding site mediates L1 promoter DNA methylation in pluripotent and differentiated cells. By analyzing 24 hippocampal neurons with three distinct single-cell genomic approaches, we characterized and validated a somatic L1 insertion bearing a 3' transduction. The source (donor) L1 for this insertion was slightly 5' truncated, lacked the YY1 binding site, and was highly mobile when tested in\ua0vitro. Locus-specific bisulfite sequencing revealed that the donor L1 and other young L1s with mutated YY1 binding sites were hypomethylated in embryonic stem cells, during neurodifferentiation, and in liver and brain tissue. These results explain how L1 can evade repression and retrotranspose in the human body

Heritable L1 retrotransposition in the mouse primordial germline and early embryo

LINE-1 (L1) retrotransposons are a noted source of genetic diversity and disease in mammals. To expand its genomic footprint, L1 must mobilize in cells that will contribute their genetic material to subsequent generations. Heritable L1 insertions may therefore arise in germ cells and in pluripotent embryonic cells, prior to germline specification, yet the frequency and predominant developmental timing of such events remain unclear. Here, we applied mouse retrotransposon capture sequencing (mRC-seq) and whole-genome sequencing (WGS) to pedigrees of C57BL/6J animals, and uncovered an L1 insertion rate of ≥1 event per eight births. We traced heritable L1 insertions to pluripotent embryonic cells and, strikingly, to early primordial germ cells (PGCs). New L1 insertions bore structural hallmarks of target-site primed reverse transcription (TPRT) and mobilized efficiently in a cultured cell retrotransposition assay. Together, our results highlight the rate and evolutionary impact of heritable L1 retrotransposition and reveal retrotransposition-mediated genomic diversification as a fundamental property of pluripotent embryonic cells in vivo