71 research outputs found
Parkour as a donor sport for athletic development in youth team sports: insights through an ecological dynamics lens
Analyses of talent development in sport have identified that skill can be enhanced through early and continued involvement in donor sports which share affordances (opportunities for action) with a performer's main target sport. Aligning key ideas of the Athletic Skills Model and ecological dynamics theory, we propose how the sport of parkour could provide a representative and adaptive platform for developing athletic skill (e.g. coordination, timing, balance, agility, spatial awareness and muscular strength). We discuss how youth sport development programmes could be (re) designed to include parkour-style activities, in order to develop general athletic skills in affordance-rich environments. It is proposed that team sports development programmes could particularly benefit from parkour-style training since it is exploratory and adaptive nature shapes utilisation of affordances for innovative and autonomous performance by athletes. Early introduction to varied, relevant activities for development of athleticism and skill, in a diversified training programme, would provide impetus for a fundamental shift away from the early specialisation approach favoured by traditional theories of skill acquisition and expertise in sport
The application of methylation specific electrophoresis (MSE) to DNA methylation analysis of the 5' CpG island of mucin in cancer cells
<p>Abstract</p> <p>Background</p> <p>Methylation of CpG sites in genomic DNA plays an important role in gene regulation and especially in gene silencing. We have reported mechanisms of epigenetic regulation for expression of mucins, which are markers of malignancy potential and early detection of human neoplasms. Epigenetic changes in promoter regions appear to be the first step in expression of mucins. Thus, detection of promoter methylation status is important for early diagnosis of cancer, monitoring of tumor behavior, and evaluating the response of tumors to targeted therapy. However, conventional analytical methods for DNA methylation require a large amount of DNA and have low sensitivity.</p> <p>Methods</p> <p>Here, we report a modified version of the bisulfite-DGGE (denaturing gradient gel electrophoresis) using a nested PCR approach. We designated this method as methylation specific electrophoresis (MSE). The MSE method is comprised of the following steps: (a) bisulfite treatment of genomic DNA, (b) amplification of the target DNA by a nested PCR approach and (c) applying to DGGE. To examine whether the MSE method is able to analyze DNA methylation of mucin genes in various samples, we apply it to DNA obtained from state cell lines, ethanol-fixed colonic crypts and human pancreatic juices.</p> <p>Result</p> <p>The MSE method greatly decreases the amount of input DNA. The lower detection limit for distinguishing different methylation status is < 0.1% and the detectable minimum amount of DNA is 20 pg, which can be obtained from only a few cells. We also show that MSE can be used for analysis of challenging samples such as human isolated colonic crypts or human pancreatic juices, from which only a small amount of DNA can be extracted.</p> <p>Conclusions</p> <p>The MSE method can provide a qualitative information of methylated sequence profile. The MSE method allows sensitive and specific analysis of the DNA methylation pattern of almost any block of multiple CpG sites. The MSE method can be applied to analysis of DNA methylation status in many different clinical samples, and this may facilitate identification of new risk markers.</p
Pten dependence distinguishes haematopoietic stem cells from leukaemia-initiating cells
Recent advances have highlighted extensive phenotypic and functional similarities between normal stem cells and cancer stem cells. This raises the question of whether disease therapies can be developed that eliminate cancer stem cells without eliminating normal stem cells. Here we address this issue by conditionally deleting the Pten tumour suppressor gene in adult haematopoietic cells. This led to myeloproliferative disease within days and transplantable leukaemias within weeks. Pten deletion also promoted haematopoietic stem cell (HSC) proliferation. However, this led to HSC depletion via a cell-autonomous mechanism, preventing these cells from stably reconstituting irradiated mice. In contrast to leukaemia-initiating cells, HSCs were therefore unable to maintain themselves without Pten. These effects were mostly mediated by mTOR as they were inhibited by rapamycin. Rapamycin not only depleted leukaemia-initiating cells but also restored normal HSC function. Mechanistic differences between normal stem cells and cancer stem cells can thus be targeted to deplete cancer stem cells without damaging normal stem cells.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62514/1/nature04703.pd
The hypoxia marker CAIX is prognostic in the UK phase III VorteX-Biobank cohort: an important resource for translational research in soft tissue sarcoma
BACKGROUND: Despite high metastasis rates, adjuvant/neoadjuvant systemic therapy for localised soft tissue sarcoma (STS) is not used routinely. Progress requires tailoring therapy to features of tumour biology, which need exploration in well-documented cohorts. Hypoxia has been linked to metastasis in STS and is targetable. This study evaluated hypoxia prognostic markers in the phase III adjuvant radiotherapy VorteX trial. METHODS: Formalin-fixed paraffin-embedded tumour biopsies, fresh tumour/normal tissue and blood were collected before radiotherapy. Immunohistochemistry for HIF-1α, CAIX and GLUT1 was performed on tissue microarrays and assessed by two scorers (one pathologist). Prognostic analysis of disease-free survival (DFS) used Kaplan-Meier and Cox regression. RESULTS: Biobank and outcome data were available for 203 out of 216 randomised patients. High CAIX expression was associated with worse DFS (hazard ratio 2.28, 95% confidence interval: 1.44-3.59, P<0.001). Hypoxia-inducible factor-1α and GLUT1 were not prognostic. Carbonic anhydrase IX remained prognostic in multivariable analysis. CONCLUSIONS: The VorteX-Biobank contains tissue with linked outcome data and is an important resource for research. This study confirms hypoxia is linked to poor prognosis in STS and suggests that CAIX may be the best known marker. However, overlap between single marker positivity was poor and future work will develop an STS hypoxia gene signature to account for tumour heterogeneity
The context and potential of epigenetics in oncology
Cancer has long been known to be a disease caused by alterations in the genetic blueprint of cells. In the past decade it has become evident that epigenetic processes have a function, at least equally important, in neoplasia. Epigenetics describes the mechanisms that result in heritable alterations in gene expression profiles without an accompanying change in DNA sequence. Genetics and epigenetics intricately interact in the pathogenesis of cancer (Esteller, 2007). In this review, we paint a broad picture of current understanding of epigenetic changes in cancer cells and reflect on the immense clinical potential of emerging knowledge of epigenetics in the diagnosis, prognostic assessment, treatment, and screening of cancer
Aberrant methylation of the Adenomatous Polyposis Coli (APC) gene promoter is associated with the inflammatory breast cancer phenotype
Aberrant methylation of the adenomatous polyposis coli (APC) gene promoter occurs in about 40% of breast tumours and has been correlated with reduced APC protein levels. To what extent epigenetic alterations of the APC gene may differ according to specific breast cancer phenotypes, remains to be elucidated. Our aim was to explore the role of APC methylation in the inflammatory breast cancer (IBC) phenotype. The status of APC gene promoter hypermethylation was investigated in DNA from normal breast tissues, IBC and non-IBC by both conventional and real-time quantitative methylation-specific PCR (MSP). APC methylation levels were compared with APC mRNA and protein levels. Hypermethylation of the APC gene promoter was present in 71% of IBC samples (n=21) and 43% of non-IBC samples (n=30) by conventional MSP (P=0.047). The APC gene also showed an increased frequency of high methylation levels in IBC (in 74% of cases, n=19) vs non-IBC (in 46% of cases, n=35) using a qMSP assay (P=0.048). We observed no significant association between APC methylation levels by qMSP and APC mRNA or protein expression levels. In conclusion, for the first time, we report the association of aberrant methylation of the APC gene promoter with the IBC phenotype, which might be of biological and clinical importance
A certified plasmid reference material for the standardisation of BCR-ABL1 mRNA quantification by real-time quantitative PCR
Serial quantification of BCR–ABL1 mRNA is an important therapeutic indicator in chronic myeloid leukaemia, but there is a
substantial variation in results reported by diff
Exploring the environmental strategy of big energy companies to drive sustainability
The purpose of this research is to provide an in-depth evaluation of the environmental strategy of the biggest energy companies to drive sustainability, i.e., for both business and the environment as a collective entity. Rooted in the theory of Corporate Social Responsibility (CSR), a secondary data analysis was conducted on the top five energy companies (i.e., British Petroleum (BP), Exxon Mobil, Gazprom, Sinopec and Saudi Aramco) as published by Enercom (2016) to investigate their approach to sustainable development. To do so, each company's environmental strategy was evaluated in order to gain a clear understanding of their implemented procedures for sustainable development towards future. This research paper gives an insight in to the main energy companies' impact on nature and assesses how sustainable their strategies are towards environmental issues. Through this evaluation, we clearly identified how climate change forces companies to be responsible towards society, the economy, and the environment. This study's finding contributes to the present body of knowledge and highlights how the big energy companies have taken responsibility for their actions towards environmental issues
Reactive oxygen species and male reproductive hormones
Reports of the increasing incidence of male infertility paired with decreasing semen quality have triggered studies
on the effects of lifestyle and environmental factors on the male reproductive potential. There are numerous exogenous
and endogenous factors that are able to induce excessive production of reactive oxygen species (ROS) beyond that of
cellular antioxidant capacity, thus causing oxidative stress. In turn, oxidative stress negatively affects male reproductive
functions and may induce infertility either directly or indirectly by affecting the hypothalamus-pituitary-gonadal (HPG)
axis and/or disrupting its crosstalk with other hormonal axes. This review discusses the important exogenous and
endogenous factors leading to the generation of ROS in different parts of the male reproductive tract. It also highlights
the negative impact of oxidative stress on the regulation and cross-talk between the reproductive hormones. It further
describes the mechanism of ROS-induced derangement of male reproductive hormonal profiles that could ultimately
lead to male infertility. An understanding of the disruptive effects of ROS on male reproductive hormones would
encourage further investigations directed towards the prevention of ROS-mediated hormonal imbalances, which in turn
could help in the management of male infertility
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