33 research outputs found
Facebook and body image concern in adolescent girls: A prospective study
© 2016 Wiley Periodicals, Inc. Objective: The primary aim of the study was to examine the relationship across time between Facebook use and body image concern in adolescent girls. Method: A sample of 438 girls in the first two years (Years 8 and 9) of high school (aged 13-15 years) at Time 1 completed questionnaire measures of Facebook consumption and body image concerns, and again two years later (Time 2). Results: Facebook involvement increased substantially over the two year time period. Body image concerns also increased. Number of Facebook friends was found to prospectively predict the observed increase in drive for thinness. On the other hand, internalization and body surveillance prospectively predicted the observed increase in number of Facebook friends. Discussion: It was concluded that Facebook âfriendshipsâ represent a potent sociocultural force in the body image of adolescent girls. © 2016 Wiley Periodicals, Inc. (Int J Eat Disord 2017; 50:80â83)
Chemically induced DNA hypomethylation in breast carcinoma cells detected by the amplification of intermethylated sites
INTRODUCTION: Compromised patterns of gene expression result in genomic instability, altered patterns of gene expression and tumour formation. Specifically, aberrant DNA hypermethylation in gene promoter regions leads to gene silencing, whereas global hypomethylation events can result in chromosomal instability and oncogene activation. Potential links exist between environmental agents and DNA methylation, but the destabilizing effects of environmental exposures on the DNA methylation machinery are not understood within the context of breast cancer aetiology. METHODS: We assessed genome-wide changes in methylation patterns using a unique methylation profiling technique called amplification of intermethylated sites (AIMS). This method generates easily readable fingerprints that represent the investigated cell line's methylation profile, based on the differential cleavage of DNA with methylation-specific isoschisomeric restriction endonucleases. RESULTS: We validated this approach by demonstrating both unique and reoccurring sites of genomic hypomethylation in four breast carcinoma cell lines treated with the cytosine analogue 5-azacytidine. Comparison of treated with control samples revealed individual bands that exhibited methylation changes, and these bands were excized and cloned, and the precise genomic location individually identified. In most cases, these regions of hypomethylation coincided with susceptible target regions previously associated with chromosome breakage, rearrangement and gene amplification. Similarly, we observed that acute benzopyrene exposure is associated with altered methylation patterns in these cell lines. CONCLUSION: These results reinforce the link between environmental exposures, DNA methylation and breast cancer, and support a role for AIMS as a rapid, affordable screening method to identify environmentally induced DNA methylation changes that occur in tumourigenesis
Interspecies somatic cell nuclear transfer is dependent on compatible mitochondrial DNA and reprogramming factors
Interspecies somatic cell nuclear transfer (iSCNT) involves the transfer of a nucleus or cell from one species into the
cytoplasm of an enucleated oocyte from another. Once activated, reconstructed oocytes can be cultured in vitro to
blastocyst, the final stage of preimplantation development. However, they often arrest during the early stages of
preimplantation development; fail to reprogramme the somatic nucleus; and eliminate the accompanying donor cellâs
mitochondrial DNA (mtDNA) in favour of the recipient oocyteâs genetically more divergent population. This last point has
consequences for the production of ATP by the electron transfer chain, which is encoded by nuclear and mtDNA. Using a
murine-porcine interspecies model, we investigated the importance of nuclear-cytoplasmic compatibility on successful
development. Initially, we transferred murine fetal fibroblasts into enucleated porcine oocytes, which resulted in extremely
low blastocyst rates (0.48%); and failure to replicate nuclear DNA and express Oct-4, the key marker of reprogramming.
Using allele specific-PCR, we detected peak levels of murine mtDNA at 0.1460.055% of total mtDNA at the 2-cell embryo
stage and then at ever-decreasing levels to the blastocyst stage (,0.001%). Furthermore, these embryos had an overall
mtDNA profile similar to porcine embryos. We then depleted porcine oocytes of their mtDNA using 10 mM 29,39-
dideoxycytidine and transferred murine somatic cells along with murine embryonic stem cell extract, which expressed key
pluripotent genes associated with reprogramming and contained mitochondria, into these oocytes. Blastocyst rates
increased significantly (3.38%) compared to embryos generated from non-supplemented oocytes (P,0.01). They also had
significantly more murine mtDNA at the 2-cell stage than the non-supplemented embryos, which was maintained
throughout early preimplantation development. At later stages, these embryos possessed 49.9962.97% murine mtDNA.
They also exhibited an mtDNA profile similar to murine preimplantation embryos. Overall, these data demonstrate that the
addition of species compatible mtDNA and reprogramming factors improves developmental outcomes for iSCNT embryos
Young childrenâs initiation into family literacy practices in the digital age
This article reports a study that explored young childrenâs digital literacy in the home. The aim of the study was to identify the range of digital literacy practices in which children are engaged in the home and to explore how these are embedded into family life and involve family members. Four children, two girls and two boys aged between 2 and 4âyears, were the focus for study. Parents were co-researchers in the study in that they made written observations on childrenâs activities and captured practices using a digital camera and a digital camcorder over the period of 1âmonth. They took part in a series of interviews during the study in which they reflected on this data and were asked about related practices. Findings suggest that children were immersed in a range of multimedia, multimodal practices which involved extensive engagement with other family members who scaffolded their learning and delighted in the childrenâs technological capabilities. The article suggests that, in the light of socio-cultural developments in the new media age, a change in focus from âfamily literacyâ to âfamily digital literacyâ is required
Metal contamination in urban street sediment in Pisa (Italy) can affect the production of antioxidant metabolites in Taraxacum officinale Weber
Taraxacum officinaleWeber (dandelion) is a very ubiquitous species and it can grow in
urban environments on metal polluted sediments deposited in the gutters. This study
represents a preliminary step to verify the presence of metals in sediments collected in
urban streets in Pisa and to assess the alteration in dandelion metabolites in order to
understand its adaptation to polluted environments. The soil and sediments were
collected at three urban streets and analyzed for total and extractable Cr, Pb, Cu, Ni,
Zn. The total values of Pb and Zn in street sediments exceeded the limits for residential
areas of soils. Zn was the most mobile of the metals analysed. Floating cultivations
trials were set up with dandelion seedlings and street sediments. The metals were
analysed in roots and leaves. Antioxidant power, anthocyanins, polyphenols, nonprotein
thiols (NP-TH) and chlorophylls were measured in dandelion leaves. The first
two parameters (anthocyanins and antioxidant power) were higher in the polluted
samples compared to the control; chlorophyll content was lower in the treated samples,
whereas NP-TH showed no differences. NP-TH groups determined in roots were
associated with the root content of Zn and Pb. These results indicate that dandelion
can tolerate plant stress by altering its metabolite conten