Detection of skewed X-chromosome inactivation in Fragile X syndrome and X chromosome aneuploidy using quantitative melt analysis.

Methylation of the fragile X mental retardation 1 (FMR1) exon 1/intron 1 boundary positioned fragile X related epigenetic element 2 (FREE2), reveals skewed X-chromosome inactivation (XCI) in fragile X syndrome full mutation (FM: CGG > 200) females. XCI skewing has been also linked to abnormal X-linked gene expression with the broader clinical impact for sex chromosome aneuploidies (SCAs). In this study, 10 FREE2 CpG sites were targeted using methylation specific quantitative melt analysis (MS-QMA), including 3 sites that could not be analysed with previously used EpiTYPER system. The method was applied for detection of skewed XCI in FM females and in different types of SCA. We tested venous blood and saliva DNA collected from 107 controls (CGG < 40), and 148 FM and 90 SCA individuals. MS-QMA identified: (i) most SCAs if combined with a Y chromosome test; (ii) locus-specific XCI skewing towards the hypomethylated state in FM females; and (iii) skewed XCI towards the hypermethylated state in SCA with 3 or more X chromosomes, and in 5% of the 47,XXY individuals. MS-QMA output also showed significant correlation with the EpiTYPER reference method in FM males and females (P < 0.0001) and SCAs (P < 0.05). In conclusion, we demonstrate use of MS-QMA to quantify skewed XCI in two applications with diagnostic utility

Who's most at risk of poor body image? Identifying subgroups of adolescent social media users over the course of a year

Types and stability of appearance-related social media use patterns remain under-explored despite established links between social media use and wellbeing. This study aimed to identify subgroups of social media users, and explore whether subgroup membership was stable over time and associated with body image-related outcomes. Adolescents (N = 766; Mage = 12.76, SD = 0.73; 49.40% female) completed four surveys across 1-year, reporting several social media use indices, body dissatisfaction, dietary restraint, and strategies to increase muscle. Latent profile analyses identified two subgroups (moderate and high users), that remained reasonably stable over time. The high subgroup exhibited poorer body image at baseline, though differences seemed to dissipate somewhat over 1-year. Examination of subgroup transition over time showed more rapid increases in poor body image outcomes among social media increasers and more rapid declines for reducers. Prevention programs which aim to reduce high levels of social media use among children, young adolescents, and high-risk individuals (i.e., appearance-focused users) appear warranted

Motivations for social media use: Associations with social media engagement and body satisfaction and well-being among adolescents

Adolescents are spending considerable time on social media, yet it is unclear whether motivations for social media use drive different forms of social media engagement, and their relationships with body satisfaction and well-being. This study tested a proposed model of the relationships between motivations for social media use, types of social media engagement and body satisfaction and well-being. Responses to an online survey from 1432 Australian adolescents (M = 13.45 years, SD = 1.14, range 11–17; 55.4% boys) were collected. Structural equational modelling indicates excellent model fit. Specifically, motivations for social media use (information sharing, passing time, escapism, social interaction, social capital and appearance feedback) were associated with engagement (intensity, photo-based use, active use, passive use and liking use) and revealed mixed associations with body satisfaction and well-being. The findings support the importance of considering motivations for social media use in future research. ag

Feasibility of neonatal dried blood spot retrieval amid evolving state policies (2009-2010): a Children's Oncology Group study

Dried blood spots (DBS) are collected uniformly from US newborns to test for metabolic and other disorders. Because evidence exists for prenatal origins of some diseases, DBS may provide unique prenatal exposure records. Some states retain residual DBS and permit their use in aetiological studies. The primary study aim was to assess the feasibility of obtaining residual DBS from state newborn screening programmes for paediatric and adolescent cancer patients nationwide with parental/subject consent/assent. Families of leukaemia and lymphoma patients aged ≤21 years diagnosed from 1998 to 2007 at randomly selected Children's Oncology Group institutions across the US were questioned (n = 947). Parents/guardians and patients aged ≥18 years were asked to release DBS to investigators in spring 2009. DBS were then requested from states. Overall, 299 families (32%) released DBS. Consenting/assenting patients were born in 39 US states and 46 DBS were obtained from five states; 124 DBS were unobtainable because patients were born prior to dates of state retention. State policies are rapidly evolving and there is ongoing discussion regarding DBS storage and secondary research uses. Currently, population-based DBS studies can be conducted in a limited number of states; fortunately, many have large populations to provide reasonably sized paediatric subject groups

Chromosomal-level assembly of the Asian Seabass genome using long sequence reads and multi-layered scaffolding

We report here the ~670 Mb genome assembly of the Asian seabass (Lates calcarifer), a tropical marine teleost. We used long-read sequencing augmented by transcriptomics, optical and genetic mapping along with shared synteny from closely related fish species to derive a chromosome-level assembly with a contig N50 size over 1 Mb and scaffold N50 size over 25 Mb that span ~90% of the genome. The population structure of L. calcarifer species complex was analyzed by re-sequencing 61 individuals representing various regions across the species' native range. SNP analyses identified high levels of genetic diversity and confirmed earlier indications of a population stratification comprising three clades with signs of admixture apparent in the South-East Asian population. The quality of the Asian seabass genome assembly far exceeds that of any other fish species, and will serve as a new standard for fish genomics

The genomes of two key bumblebee species with primitive eusocial organization

Background: The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats. Results: We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species. Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms. Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage. Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation. Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits. Conclusions: These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies. Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation

Poor Regenerative Outcome after Skeletal Muscle Necrosis Induced by Bothrops asper Venom: Alterations in Microvasculature and Nerves

artículo (arbitrado) -- Universidad de Costa Rica, Instituto de Investigaciones Clodomiro Picado. 2011Background: Viperid snakebite envenoming is characterized by prominent local tissue damage, including muscle necrosis. A frequent outcome of such local pathology is deficient skeletal muscle regeneration, which causes muscle dysfunction, muscle loss and fibrosis, thus provoking permanent sequelae that greatly affect the quality of life of patients. The causes of such poor regenerative outcome of skeletal muscle after viperid snakebites are not fully understood. Methodology/Principal Findings: A murine model of muscle necrosis and regeneration was adapted to study the effects of the venom and isolated toxins of Bothrops asper, the medically most important snake in Central America. Gastrocnemius muscle was injected with either B. asper venom, a myotoxic phospholipase A2 (Mtx), a hemorrhagic metalloproteinase (SVMP), or saline solution. At various time intervals, during one month, tissue samples were collected and analyzed by histology, and by immunocytochemical and immunohistochemical techniques aimed at detecting muscle fibers, collagen, endothelial cells, myoblasts, myotubes, macrophages, TUNEL-positive nuclei, and axons. A successful regenerative response was observed in muscle injected with Mtx, which induces myonecrosis but does not affect the microvasculature. In contrast, poor regeneration, with fibrosis and atrophic fibers, occurred when muscle was injected with venom or SVMP, both of which provoke necrosis, microvascular damage leading to hemorrhage, and poor axonal regeneration. Conclusions/Significance: The deficient skeletal muscle regeneration after injection of B. asper venom is likely to depend on the widespread damage to the microvasculature, which affects the removal of necrotic debris by phagocytes, and the provision of nutrients and oxygen required for regeneration. In addition, deficient axonal regeneration is likely to contribute to the poor regenerative outcome in this model.This study was supported by NeTropica (grant 2-N-2008), by Vicerrectoría de Investigación, Universidad de Costa Rica (project 741-A7-604). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP

Roadmap for a sustainable circular economy in lithium-ion and future battery technologies

The market dynamics, and their impact on a future circular economy for lithium-ion batteries (LIB), are presented in this roadmap, with safety as an integral consideration throughout the life cycle. At the point of end-of-life (EOL), there is a range of potential options—remanufacturing, reuse and recycling. Diagnostics play a significant role in evaluating the state-of-health and condition of batteries, and improvements to diagnostic techniques are evaluated. At present, manual disassembly dominates EOL disposal, however, given the volumes of future batteries that are to be anticipated, automated approaches to the dismantling of EOL battery packs will be key. The first stage in recycling after the removal of the cells is the initial cell-breaking or opening step. Approaches to this are reviewed, contrasting shredding and cell disassembly as two alternative approaches. Design for recycling is one approach that could assist in easier disassembly of cells, and new approaches to cell design that could enable the circular economy of LIBs are reviewed. After disassembly, subsequent separation of the black mass is performed before further concentration of components. There are a plethora of alternative approaches for recovering materials; this roadmap sets out the future directions for a range of approaches including pyrometallurgy, hydrometallurgy, short-loop, direct, and the biological recovery of LIB materials. Furthermore, anode, lithium, electrolyte, binder and plastics recovery are considered in order to maximise the proportion of materials recovered, minimise waste and point the way towards zero-waste recycling. The life-cycle implications of a circular economy are discussed considering the overall system of LIB recycling, and also directly investigating the different recycling methods. The legal and regulatory perspectives are also considered. Finally, with a view to the future, approaches for next-generation battery chemistries and recycling are evaluated, identifying gaps for research. This review takes the form of a series of short reviews, with each section written independently by a diverse international authorship of experts on the topic. Collectively, these reviews form a comprehensive picture of the current state of the art in LIB recycling, and how these technologies are expected to develop in the future

Systemic chemotherapy with or without cetuximab in patients with resectable colorectal liver metastasis (New EPOC): long-term results of a multicentre, randomised, controlled, phase 3 trial.

BACKGROUND: The interim analysis of the multicentre New EPOC trial in patients with resectable colorectal liver metastasis showed a significant reduction in progression-free survival in patients allocated to cetuximab plus chemotherapy compared with those given chemotherapy alone. The focus of the present analysis was to assess the effect on overall survival. METHODS: New EPOC was a multicentre, open-label, randomised, controlled, phase 3 trial. Adult patients (aged ≥18 years) with KRAS wild-type (codons 12, 13, and 61) resectable or suboptimally resectable colorectal liver metastases and a WHO performance status of 0-2 were randomly assigned (1:1) to receive chemotherapy with or without cetuximab before and after liver resection. Randomisation was done centrally with minimisation factors of surgical centre, poor prognosis cancer, and previous adjuvant treatment with oxaliplatin. Chemotherapy consisted of oxaliplatin 85 mg/m2 administered intravenously over 2 h, l-folinic acid (175 mg flat dose administered intravenously over 2 h) or d,l-folinic acid (350 mg flat dose administered intravenously over 2 h), and fluorouracil bolus 400 mg/m2 administered intravenously over 5 min, followed by a 46 h infusion of fluorouracil 2400 mg/m2 repeated every 2 weeks (regimen one), or oxaliplatin 130 mg/m2 administered intravenously over 2 h and oral capecitabine 1000 mg/m2 twice daily on days 1-14 repeated every 3 weeks (regimen two). Patients who had received adjuvant oxaliplatin could receive irinotecan 180 mg/m2 intravenously over 30 min with fluorouracil instead of oxaliplatin (regimen three). Cetuximab was given intravenously, 500 mg/m2 every 2 weeks with regimen one and three or a loading dose of 400 mg/m2 followed by a weekly infusion of 250 mg/m2 with regimen two. The primary endpoint of progression-free survival was published previously. Secondary endpoints were overall survival, preoperative response, pathological resection status, and safety. Trial recruitment was halted prematurely on the advice of the Trial Steering Committee on Nov 1, 2012. All analyses (except safety) were done on the intention-to-treat population. Safety analyses included all randomly assigned patients. This trial is registered with ISRCTN, number 22944367. FINDINGS: Between Feb 26, 2007, and Oct 12, 2012, 257 eligible patients were randomly assigned to chemotherapy with cetuximab (n=129) or without cetuximab (n=128). This analysis was carried out 5 years after the last patient was recruited, as defined in the protocol, at a median follow-up of 66·7 months (IQR 58·0-77·5). Median progression-free survival was 22·2 months (95% CI 18·3-26·8) in the chemotherapy alone group and 15·5 months (13·8-19·0) in the chemotherapy plus cetuximab group (hazard ratio [HR] 1·17, 95% CI 0·87-1·56; p=0·304). Median overall survival was 81·0 months (59·6 to not reached) in the chemotherapy alone group and 55·4 months (43·5-71·5) in the chemotherapy plus cetuximab group (HR 1·45, 1·02-2·05; p=0·036). There was no significant difference in the secondary outcomes of preoperative response or pathological resection status between groups. Five deaths might have been treatment-related (one in the chemotherapy alone group and four in the chemotherapy plus cetuximab group). The most common grade 3-4 adverse events reported were: neutrophil count decreased (26 [19%] of 134 in the chemotherapy alone group vs 21 [15%] of 137 in the chemotherapy plus cetuximab group), diarrhoea (13 [10%] vs 14 [10%]), skin rash (one [1%] vs 22 [16%]), thromboembolic events (ten [7%] vs 11 [8%]), lethargy (ten [7%] vs nine [7%]), oral mucositis (three [2%] vs 14 [10%]), vomiting (seven [5%] vs seven [5%]), peripheral neuropathy (eight [6%] vs five [4%]), and pain (six [4%] vs six [4%]). INTERPRETATION: Although the addition of cetuximab to chemotherapy improves the overall survival in some studies in patients with advanced, inoperable metastatic disease, its use in the perioperative setting in patients with operable disease confers a significant disadvantage in terms of overall survival. Cetuximab should not be used in this setting. FUNDING: Cancer Research UK

Clostridium difficile infection.

Infection of the colon with the Gram-positive bacterium Clostridium difficile is potentially life threatening, especially in elderly people and in patients who have dysbiosis of the gut microbiota following antimicrobial drug exposure. C. difficile is the leading cause of health-care-associated infective diarrhoea. The life cycle of C. difficile is influenced by antimicrobial agents, the host immune system, and the host microbiota and its associated metabolites. The primary mediators of inflammation in C. difficile infection (CDI) are large clostridial toxins, toxin A (TcdA) and toxin B (TcdB), and, in some bacterial strains, the binary toxin CDT. The toxins trigger a complex cascade of host cellular responses to cause diarrhoea, inflammation and tissue necrosis - the major symptoms of CDI. The factors responsible for the epidemic of some C. difficile strains are poorly understood. Recurrent infections are common and can be debilitating. Toxin detection for diagnosis is important for accurate epidemiological study, and for optimal management and prevention strategies. Infections are commonly treated with specific antimicrobial agents, but faecal microbiota transplants have shown promise for recurrent infections. Future biotherapies for C. difficile infections are likely to involve defined combinations of key gut microbiota