930 resultados para Food regulation


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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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An investigation of the drying of spherical food particles was performed, using peas as the model material. In the development of a mathematical model for drying curves, moisture diffusion was modelled using Fick’s second law for mass transfer. The resulting partial differential equation was solved using a forward-time central-space finite difference approximation, with the assumption of variable effective diffusivity. In order to test the model, experimental data was collected for the drying of green peas in a fluidised bed at three drying temperatures. Through fitting three equation types for effective diffusivity to the data, it was found that a linear equation form, in which diffusivity increased with decreasing moisture content, was most appropriate. The final model accurately described the drying curves of the three experimental temperatures, with an R2 value greater than 98.6% for all temperatures.

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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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Purpose Based on substitutes for leadership theory, the aim of this study is to examine followers' learning goal orientation as a moderator of relationships among transformational leadership, organizational citizenship behavior (OCB) and sales productivity. Design/methodology/approach Data came from 61 food and beverage attendants of a casino, and were analyzed using regression analyses. Findings Transformational leadership was positively related to both OCB and sales productivity. Learning goal orientation moderated the relationship between transformational leadership and OCB, such that transformational leadership was more strongly related to OCB among followers with a low learning goal orientation than among followers with a high learning goal orientation. Research limitations/implications Limitations of the study include the small sample size and cross-sectional research design. Practical implications Organizations could train supervisors to practice a transformational leadership style and to take followers' learning goal orientation into account. Originality/value The findings of this study suggest that, with regard to OCB, a high learning goal orientation of followers may act as a “substitute” for low levels of leaders' transformational leadership.

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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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Purpose. To evaluate the influence of co-administered vehicles on in vitro dissolution in simulated gastric fluid of crushed immediate release tablets as an indicator for potential drug bioavailability compromise. Methods. Release and dissolution of crushed amlodipine, atenolol, carbamazepine and warfarin tablets were tested with six foods and drinks that are frequently used in the clinical setting as mixers for crushed medications (water, orange juice, honey, yoghurt, strawberry jam and water thickened with Easythick powder) in comparison to whole tablets. Five commercial thickening agents (Easythick Advanced, Janbak F, Karicare, Nutilis, Viscaid) at three thickness levels were tested for their effect on the dissolution of crushed atenolol tablets. Results. Atenolol dissolution was unaffected by mixing crushed tablets with thin fluids or food mixers in comparison to whole tablets or crushed tablets in water, but amlodipine was delayed by mixing with jam. Mixing crushed warfarin and carbamazepine tablets with honey, jam or yoghurt caused them to resemble the slow dissolution of whole tablets rather than the faster dissolution of crushed tablets in water or orange juice. Crushing and mixing any of the four medications with thickened water caused a significant delay in dissolution. When tested with atenolol, all types of thickening agents at the greatest thickness significantly restricted dissolution, and products that are primarily based on xanthan gum also delayed dissolution at the intermediate thickness level. Conclusions. Dissolution testing, while simplistic, is a widely used and accepted method for comparing drug release from different formulations as an indicator for in vivo bioavailability. Thickened fluids have the potential to retard drug dissolution when used at the thickest levels. These findings highlight potential clinical implications of the addition of these agents to medications for the purpose of dose delivery and indicate that further investigation of thickened fluids and their potential to influence therapeutic outcomes is warranted.

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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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INTRODUCTION Globally, one-third of food production is lost annually due to negligent authorities. India alone loses some 21 million tonnes of wheat per year even while it has 200 million food-insecure people in the nation. Disturbingly provocative as it may sound, it is amazing how national and international institutions and governments make use of human hunger for their own survival (Raghib 2013). The global food system is increasingly insecure. Challenges to long-term global food security are encapsulated by resource scarcity, environmental degradation, biodiversity loss, climate change, reductions of farm labour and a growing world population. These issues are caused and aggravated by the spread of corporatised and monopolised food systems, dietary change, and urbanisation. These factors have rapidly brought food insecurity under the umbrella of unconventional security threats (Heukelom 2011). For some, humanitarian crises associated with food insecurity, or what has been dubbed ‘the silent tsunami’, is a pending peril, notably for the world’s poorest and most vulnerable people. For others, the food production industry is an emerging market with unprecedented profits. Despite this problem of food scarcity we are witnessing extraordinary ‘food wastage’, notably in North America and Europe, on a scale that would reportedly be capable of feeding the world’s hungry six times over (Stuart 2012). As the opening quotation to this chapter suggests, governments and corporations are deeply involved in the contexts, politics, and resources associated with food related issues. As many economically developed and advanced industrial nations are reporting a rise out of recession, announcements are made by the world’s richest countries that they are to cut $US2 billion per year from food aid. The head of the World Food Aid Programme, Rosette Sheeran, warns that such cuts could result in ‘the loss of a generation’ (Walters 2011). The global food crisis has also reinvigorated debates about agricultural development and genetically modified (GM) food; as well as fuelling debates about poverty, debt and security. This chapter provides a discussion of the political economy of global food debates and explores the threats and opportunities surrounding food production and future food security.

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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.