992 resultados para ART regulation


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Fruit softening in apple (Malus 3 domestica) is associated with an increase in the ripening hormone ethylene. Here, we show that in cv Royal Gala apples that have the ethylene biosynthetic gene ACC OXIDASE1 suppressed, a cold treatment preconditions the apples to soften independently of added ethylene. When a cold treatment is followed by an ethylene treatment, a more rapid softening occurs than in apples that have not had a cold treatment. Apple fruit softening has been associated with the increase in the expression of cell wall hydrolase genes. One such gene, POLYGALACTURONASE1 (PG1), increases in expression both with ethylene and following a cold treatment. Transcriptional regulation of PG1 through the ethylene pathway is likely to be through an ETHYLENE-INSENSITIVE3-like transcription factor, which increases in expression during apple fruit development and transactivates the PG1 promoter in transient assays in the presence of ethylene. A coldrelated gene that resembles a COLD BINDING FACTOR (CBF) class of gene also transactivates the PG1 promoter. The transactivation by the CBF-like gene is greatly enhanced by the addition of exogenous ethylene. These observations give a possible molecular mechanism for the coldand ethylene-regulated control of fruit softening and suggest that either these two pathways act independently and synergistically with each other or cold enhances the ethylene response such that background levels of ethylene in the ethylene-suppressed apples is sufficient to induce fruit softening in apples.

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High-temperature, low-light (HTLL) treatment of 35S:PAP1 Arabidopsis thaliana over-expressing the PAP1 (Production of Anthocyanin Pigment 1) gene results in reversible reduction of red colouration, suggesting the action of additional anthocyanin regulators. High-performance liquid chromatography (HPLC), liquid chromatography mass spectrometry (LCMS) and Affimetrix®-based microarrays were used to measure changes in anthocyanin, flavonoids, and gene expression in response to HTLL. HTLL treatment of control and 35S:PAP1 A. thaliana resulted in a reversible reduction in the concentrations of major anthocyanins despite ongoing over-expression of the PAP1 MYB transcription factor. Twenty-one anthocyanins including eight cis-coumaryl esters were identified by LCMS. The concentrations of nine anthocyanins were reduced and those of three were increased, consistent with a sequential process of anthocyanin degradation. Analysis of gene expression showed down-regulation of flavonol and anthocyanin biosynthesis and of transport-related genes within 24 h of HTLL treatment. No catabolic genes up-regulated by HTLL were found. Reductions in the concentrations of anthocyanins and down-regulation of the genes of anthocyanin biosynthesis were achieved by environmental manipulation, despite ongoing over-expression of PAP1. Quantitative PCR showed reduced expression of three genes (TT8, TTG1 and EGL3) of the PAP1 transcriptional complex, and increased expression of the potential transcriptional repressors AtMYB3, AtMYB6 and AtMYBL2 coincided with HTLL-induced down-regulation of anthocyanin biosynthesis. HTLL treatment offers a model system with which to explore anthocyanin catabolism and to discover novel genes involved in the environmental control of anthocyanins.

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Research Findings The present study investigated whether active play during recess was associated with self-regulation and academic achievement in a prekindergarten sample. A total of 51 children in classes containing approximately half Head Start children were assessed on self-regulation, active play, and early academic achievement. Path analyses indicated that higher active play was associated with better self-regulation, which in turn was associated with higher scores on early reading and math assessments. Practice or Policy Results point to the benefits of active play for promoting self-regulation and offer insight into possible interventions designed to promote self-regulation and academic achievement.

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Self-regulation refers to our individual capacities to regulate our behaviours, emotions, and thoughts, with these skills developing rapidly across early childhood. This thesis examined sleep, emotional, and cognitive regulation development, and related parental influences, for children participating in the Longitudinal Study of Australian Children. Important longitudinal associations among children's self-regulation, maternal mental health, parenting, and later behaviour problems for children were also investigated. A unique contribution of this research was a prevalence estimate of early childhood self-regulation problems in Australian children that was documented for the first time.

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Background The behaviour of tumour cells depends on factors such as genetics and the tumour microenvironment. The latter plays a crucial role in normal mammary gland development and also in breast cancer initiation and progression. Breast cancer tissues tend to be highly desmoplastic and dense matrix as a pre-existing condition poses one of the highest risk factors for cancer development. However, matrix influence on tumour cell gene expression and behaviour such as cell migration is not fully elucidated. Results We generated high-density (HD) matrices that mimicked tumour collagen content of 20 mg/cm3 that were ~14-fold stiffer than low-density (LD) matrix of 1 mg/cm3. Live-cell imaging showed breast cancer cells utilizing cytoplasmic streaming and cell body contractility for migration within HD matrix. Cell migration was blocked in the presence of both the ROCK inhibitor, Y-27632, and the MMP inhibitor, GM6001, but not by the drugs individually. This suggests roles for ROCK1 and MMP in cell migration are complicated by compensatory mechanisms. ROCK1 expression and protein activity, were significantly upregulated in HD matrix but these were blocked by treatment with a histone deacetylase (HDAC) inhibitor, MS-275. In HD matrix, the inhibition of ROCK1 by MS-275 was indirect and relied upon protein synthesis and Notch1. Inhibition of Notch1 using pooled siRNA or DAPT abrogated the inhibition of ROCK1 by MS-275. Conclusion Increased matrix density elevates ROCK1 activity, which aids in cell migration via cell contractility. The upregulation of ROCK1 is epigenetically regulated in an indirect manner involving the repression of Notch1. This is demonstrated from inhibition of HDACs by MS-275, which caused an upregulation of Notch1 levels leading to blockade of ROCK1 expression.

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This review will focus on the role of sphingosine and its phosphorylated derivative sphingosine-1-phosphate (SPP) in cell growth regulation and signal transduction. We will show that many of the effects attributed to sphingosine in quiescent Swiss 3T3 fibroblasts are mediated via its conversion to SPP. We propose that SPP has appropriate properties to function as an intracellular second messenger based on the following: it elicits diverse cellular responses; it is rapidly produced from sphingosine by a specific kinase and rapidly degraded by a specific lyase; its concentration is low in quiescent cells but increases rapidly and transiently in response to the growth factors, fetal calf serum (FCS) and platelet derived growth factor (PDGF); it releases Ca2+ from internal sources in an InsP3-independent manner; and finally, it may link sphingolipid signaling pathways to cellular ras-mediated signaling pathways by elevating phosphatidic acid levels. The effects of this novel second messenger on growth, differentiation and invasion of human breast cancer cells will be discussed. © 1994 Kluwer Academic Publishers.

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The Australian Taxation Office (AT)) attempted to challenge both the private equity fund reliance on double tax agreements and the assertion that profits were capital in nature in its dispute with private equity group TPG. Failure to resolve the dispute resulted in the ATO issuing two taxation determinations: TD 2010/20 which states that the general anti-avoidance provisions can apply to arrangements designed to alter the intended effect of Australia's international tax agreements net; and TD 2010/21 which states that the profits on the sale of shares in a company group acquired in a leveraged buyout is assessable income. The purpose of this article is to determine the effectiveness of the administrative rulings regime as a regulatory strategy. This article, by using the TPG-Myer scenario and subsequent tax determinations as a case study, collects qualitative data which is then analysed (and triangulated) using tonal and thematic analysis. Contemporaneous commentary of private equity stakeholders, tax professionals, and media observations are analysed and evaluated within a framework of responsive regulation and utilising the current ATO compliance model. Contrary to the stated purpose of the ATO rulings regime to alleviate complexities in Australian taxation law and provide certainty to taxpayers, and despite the de facto law status afforded these rulings, this study found that the majority of private equity stakeholders and their advisors perceived that greater uncertainty was created by the two determinations. Thus, this study found that in the context of private equity fund investors, a responsive regulation measure in the form of taxation determinations was not effective.

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Estrogen increases the ability of the estrogen-dependent MCF-7 human breast cancer cell line to both proliferate and invade through an artificial basement membrane. In studying the response of MCF-7 cells to various antiestrogens, we found that 4-hydroxytamoxifen and tamoxifen inhibited cell proliferation but increased their invasiveness. In contrast, the structurally unrelated benzothiophene antiestrogens, LY117018 and LY156758, were potent antiproliferative agents which did not stimulate invasiveness. The differential effects of these antiestrogenic agents on invasion correlated with changes in production of collagenase IV, while no significant change was seen in the chemotactic activity of the cells. Invasiveness was increased by 17β-estradiol or 4-hydroxytamoxifen after a few hours of treatment and was rapidly lost when 17β-estradiol was withdrawn. Stimulation of invasiveness with 17β-estradiol was blocked by the antiestrogen, LY117018. Cells from the MDA-MB-231 line which lacks estrogen receptors were not affected by estrogen or antiestrogen in terms of proliferation or invasion. These studies indicate that the invasiveness of MCF-7 cells is regulated by antiestrogens through the estrogen receptor and may be mediated by collagenase IV activity. Antiestrogens which reduce both the proliferation and invasiveness of these cells may be interesting new candidates for clinical application.

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Matrix Metalloproteinase-2 (MMP-2) is secreted as a zymogen, the activation of which has been associated with metastatic progression in human breast cancer (HBC). Concanavalin A (Con A) has been found to induce activation of MMP-2 in invasive HBC cell lines. Con A effects on the expression of mRNA for membrane-type matrix metalloproteinase (MT-MMP), a newly described cell surface-associated MMP, showed a close temporal correlation with induction of MMP-2 activation. It is surprising that MT-MMP mRNA is constitutively present in the uninduced MDA-MB-231 cell, despite a lack of MMP-2 activation. We have used actinomycin D to demonstrate a partial requirement for de novo gene expression in the induction of MMP-2 activation by Con A in MDA-MB-231 HBC cells. Furthermore, this transcriptional response to Con A appeared to require the continued presence of Con A for its manifestation. The nontranscriptional component of the Con A induction manifests rapidly, is quite substantial, and persists strongly despite actinomycin D abrogation of both constitutive and Con A-induced MT-MMP. Cycloheximide analyses suggest that protein synthesis may be involved in this rapid transcription-independent response. These studies suggest that Con A induces MMP-2-activation in part by up-regulation of MT-MMP expression but has a more complicated mode of action, involving additional nontranscriptional effects, which apparently require protein synthesis.

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The level of 67 kDa laminin receptor (67LR) expression on breast and colon tumor cell surfaces was previously shown to be correlated with the capacity of tumor cells to metastasize. In the present work we investigate the effects of progestins and estrogen on the expression of 67LR in two sublines of the T47D human breast cancer cells: weakly tumorigenic, poorly invasive parental T47D cells and a highly tumorigenic, more invasive T47Dco subclone. Inmmunoblotting with an affinity purified antibody directed against a synthetic peptide recognizes the 67LR in these cells. 67LR expression in the T47Dco subclone is 5,5-fold higher than in their parental T47D cells. Treatment of T47D cells with 1 nM of the synthetic progestin R5020 results in a 4-fold increase in 67LR protein expression. Estrogen also induced 67LR expression, but only by 1.5-fold. The progestin-stimulated expression of the 67LR correlates with a 4.3-fold increase in attachment of T47D cells to laminin. A monoclonal antibody, mAb 13, directed against β1 integrin, completely blocks the attachment of T47D cells to fibronectin, only partially inhibits the attachment of T47D cells to laminin, and appears not to affect the progestin-stimulated laminin attachment of T47D cells. A new antiprogestin, ZK 112.993, significantly inhibits both progestin-stimulated 67LR expression and the increased attachment to laminin. These results suggest a possible role for progestin in mediating one of the multiple events thought to be important in metastasis of steroid receptor positive human breast cancer cells.

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One of the forces which has indelibly shaped marketing is the internet. It has not only changed the way we communicate, but our marketing practices and our advertising self-regulation process (Kerr, Mortimer, Dickinson and Waller 2012). This special session seeks to build a new global framework to regulate advertising activity in this uncharted online environment. It looks back to how advertising has been traditionally self-regulated and looks forward to identify the key issues for marketers, consumers, regulators and the media. This special session explores and reinforces the fundamental purpose of the conference, as well as addressing the urgent needs of marketers, consumers and regulators.

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Research background Art of Sleeping’s “Like a Thief” is an EP of popular music produced at Airlock studios and released in 2012 by the record label Dew Process. “Like a Thief” contributes to studies in the field of music production, as well as furthering research into the role of of national radio play in the development of emerging musicians and artists. Using Australian bands such as Boy and Bear as a reference point, the EP showcases the vocal range of Caleb Hodges and investigates possibilities in extending the modes of musicality possible within the recording studio through use of multiple layering of processed keyboards and electric guitar. Scholars such as Ben Eltham and journalists such as Everett True have written about the importance of the support of Australia’s national youth broadcaster Triple J in the early stages of a band’s development. The approach of the production of the EP was conceived with this agenda in mind, and asked, what can we learn about the relationships between popular music production, distribution and consumption, and the role that national public radio has come to play in the Australian context? Research contribution This project has identified that certain avenues of the music industry continue to aligned with Triple J airplay, that these avenues play an important role in the level of success that artists are likely to achieve, and that targeted understanding of music production techniques and aesthetics may contribute to success in this regard. Research significance The EP’s two singles were both in the top 100 most frequently played tracks on Triple J in 2012, and the band were able to leverage this exposure in securing a record deal with Dew Process, along with being selected as part of the competitive peer review process for festival performances such as Splendour in the Grass. The work received positive peer reviews, with indieshuffle writing: “Brisbane's Art of Sleeping are a truly talented band. … the five-piece gained plenty of local attention earlier this year with their stunning single "Empty Hands.” This was the first single off their new EP, Like a Thief, which was produced by the renowned Yanto Browning (The Medics, The Jungle Giants) … The EP includes five tracks of incredible power and sentiment … Title track "Like a Thief” is … [a] standout, again a vast and expansive song which showcases the band's completeness”

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To date, a wide range of methods has been used to measure physical activity in children and adolescents. These include self-report methods such as questionnaires, activity logs, and diaries as well as objective measures of physical activity such as direct observation, doubly labeled water, heart rate monitoring, accelerometers, and pedometers. The purpose of this review is to overview the methods currently being used to measure physical activity in children and adolescents. For each measurement approach, new developments and/or innovations are identified and discussed. Particular attention is given to the use of accelerometers and the calibration of accelerometer output to units of energy expenditure to developing children.

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Human skin fibroblasts were cultured long-term in the presence of ascorbic acid to allow formation of a three-dimensional collagen matrix, and the effects of this on activation of secreted matrix metalloproteinase-2 (MMP-2) were examined. Accumulation of collagen over time correlated with increased levels of both mature MMP-2 and cell-associated membrane type 1-MMP (MT1-MMP), and subsequently increased mRNA levels for MT1-MMP, providing temporal resolution of the "nontranscriptional" and "transcriptional" effects of collagen on MT-1MMP functionality. MMP-2 activation by these cultures was blocked by inhibitors of prolyl-4-hydroxylase, or when fibroblasts derived from the collagen α1(I) gene-deficient Mov-13 mouse were used. MMP-2 activation by the Mov-13 fibroblasts was rescued by transfection of a full-length α1(I) collagen cDNA, and to our surprise, also by transfection with an α1(I) collagen cDNA carrying a mutation at the C-proteinase cleavage, which almost abrogated fibrillogenesis. Although studies with ascorbate-cultured MT1-MMP-/- fibroblasts showed that MT1-MMP played a significant role in the collagen-induced MMP-2 activation, a residual MT1-MMP-independent activation of MMP-2 was seen which resembled the level of MMP-2 activation persisting when wild-type fibroblasts were cultured in the presence of both ascorbic acid and MMP inhibitors. We were also unable to block this residual activation with inhibitors specific for serinyl, aspartyl, or cysteinyl enzymes.