987 resultados para regulate


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Using interview data on LGBT young peoples’ policing experiences, I argue policing practices work to constrain public visibilities of sexual and gender diversity in public spaces. Police actions recounted by LGBT young people suggest the workings of a certain kind of visuality (Mason, 2002) and evidenced more subtle actions that sought to constrain, regulate, and punish public visibilities of sexual and gender diversity. Aligning with the work of sexualities academics and theorists, this paper suggests that, like violence is itself a bodily spectacle from which onlookers come to know things, policing works to subtly constrain public visibilities of “queerness”. Policing interactions with LGBT young people serves the purpose of visibly yet unverifiably (Mason, 2002) regulating displays of sexual and gender diversity in public spaces. The paper concludes noting how police actions are nonetheless visible and therefore make knowable to the public the importance of keeping same sex intimacy invisible in public spaces.

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The use of adherent monolayer cultures have produced many insights into melanoma cell growth and differentiation, but often novel therapeutics demonstrated to act on these cells are not active in vivo. It is imperative that new methods of growing melanoma cells that reflect growth in vivo are investigated. To this end, a range of human melanoma cell lines passaged as adherent cultures or induced to form melanoma spheres (melanospheres) in stem cell media have been studied to compare cellular characteristics and protein expression. Melanoma spheres and tumours grown from cell lines as mouse xenografts had increased heterogeneity when compared with adherent cells and 3D-spheroids in agar (aggregates). Furthermore, cells within the melanoma spheres and mouse xenografts each displayed a high level of reciprocal BRN2 or MITF expression, which matched more closely the pattern seen in human melanoma tumours in situ, rather than the propensity for co-expression of these important melanocytic transcription factors seen in adherent cells and 3D-spheroids. Notably, when the levels of the BRN2 and MITF proteins were each independently repressed using siRNA treatment of adherent melanoma cells, members of the NOTCH pathway responded by decreasing or increasing expression, respectively. This links BRN2 as an activator, and conversely, MITF as a repressor of the NOTCH pathway in melanoma cells. Loss of the BRN2-MITF axis in antisense-ablated cell lines decreased the melanoma sphere-forming capability, cell adhesion during 3D-spheroid formation and invasion through a collagen matrix. Combined, this evidence suggests that the melanoma sphere-culture system induces subpopulations of cells that may more accurately portray the in vivo disease, than the growth as adherent melanoma cells.

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The purpose of this paper is to provide a basis from which to start an informed and rational dialogue in Australia about voluntary euthanasia (VE) and assisted suicide (AS). It does this by seeking to chart the broad landscape of issues that can be raised as relevant to how this conduct should be regulated by the law. It is not our purpose to persuade. Rather, we have attempted to address the issues as neutrally as possible and to canvass both sides of the argument in an even-handed manner. We hope that this exercise places the reader in a position to consider the question posed by this paper: How should Australia regulate voluntary euthanasia and assisted suicide? In line with the approach taken in the paper, this question does not take sides in the debate. It simply asks how VE and AS should be regulated, acknowledging that both prohibition and legalisation of such conduct involve regulation. We begin by considering the wider legal framework that governs end of life decision-making. Decisions to withhold or withdraw life-sustaining treatment that result in a person’s death can be lawful. This could be because, for example, a competent adult refuses such treatment. Alternatively, stopping or not providing treatment can be lawful when it is no longer in a person’s best interests to receive it. The law also recognises that appropriate palliative care should not attract criminal responsibility. By contrast, VE and AS are unlawful in Australia and could lead to prosecution for crimes such as murder, manslaughter or aiding and abetting suicide. But this is not to say that such conduct does not occur in practice. Indeed, there is a body of evidence that VE and AS occur in Australia, despite them being unlawful. There have been repeated efforts to change the law in this country, mainly by the minor political parties. However, apart from a brief period when VE and AS was lawful in the Northern Territory, these attempts to reform the law have been unsuccessful. The position is different in a small but increasing number of jurisdictions overseas where such conduct is lawful. The most well known is the Netherlands but there are also statutory regimes that regulate VE and/or AS in Belgium and Luxembourg in Europe, and Oregon and Washington in the United States. A feature of these legislative models is that they incorporate review or oversight processes that enable the collection of data about how the law is being used. As a result, there is a significant body of evidence that is available for consideration to assess the operation of the law in these jurisdictions and some of this is considered briefly here. Assisting a suicide, if done for selfless motives, is also legal in Switzerland, and this has resulted in what has been referred to as ‘euthanasia tourism’. This model is also considered. The paper also identifies the major arguments in favour of, and against, legalisation of VE and AS. Arguments often advanced in favour of law reform include respect for autonomy, that public opinion favours reform, and that the current law is incoherent and discriminatory. Key arguments against legalising VE and AS point to the sanctity of life, concerns about the adequacy and effectiveness of safeguards, and a ‘slippery slope’ that will allow euthanasia to occur for minors or for adults where it is not voluntary. We have also attempted to step beyond these well trodden and often rehearsed cases ‘for and against’. To this end, we have identified some ethical values that might span both sides of the debate and perhaps be the subject of wider consensus. We then outline a framework for considering the issue of how Australia should regulate VE and AS. We begin by asking whether such conduct should be criminal acts (as they presently are). If VE and AS should continue to attract criminal responsibility, the next step is to enquire whether the law should punish such conduct more or less than is presently the case, or whether the law should stay the same. If a change is favoured as to how the criminal law punishes VE and AS, options considered include sentencing reform, creating context-specific offences or developing prosecutorial guidelines for how the criminal justice system deals with these issues. If VE and AS should not be criminal acts, then questions arise as to how and when they should be permitted and regulated. Possible elements of any reform model include: ensuring decision-making is competent and voluntary; ascertaining a person’s eligibility to utilise the regime, for example, whether it depends on him or her having a terminal illness or experiencing pain and suffering; and setting out processes for how any decision must be made and evidenced. Options to bring about decriminalisation include challenging the validity of laws that make VE and AS unlawful, recognising a defence to criminal prosecution, or creating a statutory framework to regulate the practice. We conclude the paper where we started: with a call for rational and informed consideration of a difficult and sensitive issue. How should Australia regulate voluntary euthanasia and assisted suicide?

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This paper invites consideration of how Australia should regulate voluntary euthanasia and assisted suicide. We have attempted to pose this question as neutrally as possible, acknowledging that both prohibition and legalisation of such conduct involve decisions about regulation. We begin by charting the wider field of law at the end of life, before considering the repeated, but ultimately unsuccessful, attempts at law reform in Australia. The situation in Australia is contrasted with permissive jurisdictions overseas where voluntary euthanasia and/or assisted suicide are lawful. We consider the arguments for and against legalisation of such conduct along with the available empirical evidence as to what happens in practice both in Australia and overseas. The paper concludes by outlining a framework for deliberating on how Australia should regulate voluntary euthanasia and assisted suicide. We ask a threshold question of whether such conduct should be criminal acts (as they presently are), the answer to which then leads to a range of possible regulatory options.

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Purpose The neuromuscular mechanisms determining the mechanical behaviour of the knee during landing impact remain poorly understood. It was hypothesised that neuromuscular preparation is subject-specific and ranges along a continuum from passive to active. Methods A group of healthy men (N = 12) stepped-down from a knee-high platform for 60 consecutive trials. Surface EMG of the quadriceps and hamstrings was used to determine pre-impact onset timing, activation amplitude and cocontraction for each trial. Partial least squares regression was used to associate pre-impact preparation with post-impact knee stiffness and coordination. Results The group analysis revealed few significant changes in pre-impact preparation across trial blocks. Single-subject analyses revealed changes in muscle activity that varied in size and direction between individuals. Further, the association between pre-impact preparation and post-impact knee mechanics was subject-specific and ranged along a continuum of strategies. Conclusion The findings suggest that neuromuscular preparation during step landing is subject-specific and its association to post-impact knee mechanics occurs along a continuum, ranging from passive to active control strategies. Further work should examine the implications of these strategies on the distribution of knee forces in-vivo.

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Integration of small-scale electricity generators, known as Distributed Generation (DG), into the distribution networks has become increasingly popular at the present. This tendency together with the falling price of synchronous-type generator has potential to give the DG a better chance in participating in the voltage regulation process together with other devices already available in the system. The voltage control issue turns out to be a very challenging problem for the distribution engineers since existing control coordination schemes would need to be reconsidered to take into account the DG operation. In this paper, we propose a control coordination technique, which is able to utilize the ability of the DG as a voltage regulator, and at the same time minimizes interaction with other active devices, such as On-load Tap Changing Transformer (OLTC) and voltage regulator. The technique has been developed based on the concept of control zone, Line Drop Compensation (LDC), as well as the choice of controller's parameters. Simulations carried out on an Australian system show that the technique is suitable and flexible for any system with multiple regulating devices including DG.

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Rat testicular cells in culture produce several metalloproteinases including type IV collagenases (Sang et al. Biol Reprod 1990; 43:946-955, 956-964). We have now investigated the regulation of testicular cell type IV collagenase and other metalloprotemases in vitro. Soluble laminin stimulated Sertoli cell type IV collagenase mRNA levels. However, three peptides corresponding to different domains of the laminin molecule (CSRAKQAASIKVASADR, FALRGDNP, CLQDGDVRV) did not influence type IV collagenase mENA levels. Zyniographic analysis of medium collected from these cultures revealed that neither soluble laminin nor any of the peptides influenced 72-Wa type IV collagenase protein levels. However, peptide FALRGDNP resulted in both, a selective increase in two higher molecular-weight metalloprotemnases (83 kDa and 110 Wa and in an activation of the 72-Wa rat type IV collagenase. Interleukin-1, phorbol ester, testosterone, and FSH did not affect collagenase activation, lmmunocytochemical studies demonstrated that the addition of soluble laminin resulted in a redistribution of type IV collagenase from intracellular vesicles to the cell-substrate region beneath the cells. Peptide FALRGDNP induced a change from a vesicular to peripheral plasma membrane type of staining pattern. Zymography of plasma membrane preparations demonstrated triton-soluble gelatinases of 76 Wa, 83 Wa, and 110 Wa and a triton-insoluble gelatinase of 225 Wa, These results indicate that testicular cell type IV collagenase mRNA levels, enzyme activation, and distribution are influenced by laminin and RGD-containing peptides.

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Geminin was identified in Xenopus as a dual function protein involved in the regulation of DNA replication and neural differentiation. In Xenopus, Geminin acts to antagonize the Brahma (Brm) chromatin-remodeling protein, Brg1, during neural differentiation. Here, we investigate the interaction of Geminin with the Brm complex during Drosophila development. We demonstrate that Drosophila Geminin (Gem) interacts antagonistically with the Brm–BAP complex during wing development. Moreover, we show in vivo during wing development and biochemically that Brm acts to promote EGFR–Ras–MAPK signaling, as indicated by its effects on pERK levels, while Gem opposes this. Furthermore, gem and brm alleles modulate the wing phenotype of a Raf gain-of-function mutant and the eye phenotype of a EGFR gain-of-function mutant. Western analysis revealed that Gem over-expression in a background compromised for Brm function reduces Mek (MAPKK/Sor) protein levels, consistent with the decrease in ERK activation observed. Taken together, our results show that Gem and Brm act antagonistically to modulate the EGFR–Ras–MAPK signaling pathway, by affecting Mek levels during Drosophila development.

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Background Dysfunctional lymphatic vessel formation has been implicated in a number of pathological conditions including cancer metastasis, lymphedema, and impaired wound healing. The vascular endothelial growth factor (VEGF) family is a major regulator of lymphatic endothelial cell (LEC) function and lymphangiogenesis. Indeed, dissemination of malignant cells into the regional lymph nodes, a common occurrence in many cancers, is stimulated by VEGF family members. This effect is generally considered to be mediated via VEGFR-2 and VEGFR-3. However, the role of specific receptors and their downstream signaling pathways is not well understood. Methods and Results Here we delineate the VEGF-C/VEGF receptor (VEGFR)-3 signaling pathway in LECs and show that VEGF-C induces activation of PI3K/Akt and MEK/Erk. Furthermore, activation of PI3K/Akt by VEGF-C/VEGFR-3 resulted in phosphorylation of P70S6K, eNOS, PLCc1, and Erk1/2. Importantly, a direct interaction between PI3K and VEGFR-3 in LECs was demonstrated both in vitro and in clinical cancer specimens. This interaction was strongly associated with the presence of lymph node metastases in primary small cell carcinoma of the lung in clinical specimens. Blocking PI3K activity abolished VEGF-C-stimulated LEC tube formation and migration. Conclusions Our findings demonstrate that specific VEGFR-3 signaling pathways are activated in LECs by VEGF-C. The importance of PI3K in VEGF-C/VEGFR-3-mediated lymphangiogenesis provides a potential therapeutic target for the inhibition of lymphatic metastasis.

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The aim of this study was to investigate the expression of GABAB receptors, a subclass of receptors to the inhibitory neurotransmitter gamma-aminobutyric acid (GABAB), in human aortic smooth muscle cells (HASMCs), and to explore if altering receptor activation modified intracellular Ca(2+) concentration ([Ca(2+)]i) of HASMCs. Real-time PCR, western blots and immunofluorescence were used to determine the expression of GABABR1 and GABABR2 in cultured HASMCs. Immunohistochemistry was used to localize the two subunits in human left anterior descending artery (LAD). The effects of the GABAB receptor agonist baclofen on [Ca(2+)]i in cultured HASMCs were demonstrated using fluo-3. Both GABABR1 and GABABR2 mRNA and protein were identified in cultured HASMCs and antibody staining was also localized to smooth muscle cells of human LAD. 100 μM baclofen caused a transient increase of [Ca(2+)]i in cultured HASMCs regardless of whether Ca(2+) was added to the medium, and the effects were inhibited by pre-treatment with CGP46381 (selective GABAB receptor antagonist), pertussis toxin (a Gi/o protein inhibitor), and U73122 (a phospholipase C blocker). GABAB receptors are expressed in HASMCs and regulate the [Ca(2+)]i via a Gi/o-coupled receptor pathway and a phospholipase C activation pathway

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GABAB receptors associate with Gi/o-proteins that regulate voltage-gated Ca(2+) channels and thus the intracellular Ca(2+) concentration ([Ca(2+)]i), there is also reported cross-regulation of phospholipase C. These associations have been studied extensively in the brain and also shown to occur in non-neural cells (e.g. human airway smooth muscle). More recently GABAB receptors have been observed in chick retinal pigment epithelium (RPE). The aims were to investigate whether the GABAB receptor subunits, GABAB1 and GABAB2, are co-expressed in cultured human RPE cells, and then determine if the GABAB receptor similarly regulates the [Ca(2+)]i of RPE cells and if phospholipase C is involved. Human RPE cells were cultured from 5 donor eye cups. Evidence for GABAB1 and GABAB2 mRNAs and proteins in the RPE cell cultures were investigated using real time PCR, western blots and immunofluorescence. The effects of the GABAB receptor agonist baclofen, antagonist CGP46381, a Gi/o-protein inhibitor pertussis toxin, and the phospholipase C inhibitor U73122 on [Ca(2+)]i in cultured human RPE were demonstrated using Fluo-3. Both GABAB1 and GABAB2 mRNA and protein were identified in cell cultures of human RPE; antibody staining was co-localized to the cell membrane and cytoplasm. One-hundred μM baclofen caused a transient increase in the [Ca(2+)]i of RPE cells regardless of whether Ca(2+) was added to the buffer. Baclofen induced increases in the [Ca(2+)]i were attenuated by pre-treatment with CGP46381, pertussis toxin, and U73122. GABAB1 and GABAB2 are co-expressed in cell cultures of human RPE. GABAB receptors in RPE regulate the [Ca(2+)]i via a Gi/o-protein and phospholipase C pathway.

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The biological impact of Rho depends critically on the precise subcellular localization of its active, GTP-loaded form. This can potentially be determined by the balance between molecules that promote nucleotide exchange or GTP hydrolysis. However, how these activities may be coordinated is poorly understood. We now report a molecular pathway that achieves exactly this coordination at the epithelial zonula adherens. We identify an extramitotic activity of the centralspindlin complex, better understood as a cytokinetic regulator, which localizes to the interphase zonula adherens by interacting with the cadherin-associated protein, α-catenin. Centralspindlin recruits the RhoGEF, ECT2, to activate Rho and support junctional integrity through myosin IIA. Centralspindlin also inhibits the junctional localization of p190 B RhoGAP, which can inactivate Rho. Thus, a conserved molecular ensemble that governs Rho activation during cytokinesis is used in interphase cells to control the Rho GTPase cycle at the zonula adherens

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Integration of small-scale electricity generators, known as distributed generation (DG), into the distribution networks has become increasingly popular at the present. This tendency together with the falling price of the synchronous-type generator has potential to give DG a better chance at participating in the voltage regulation process together with other devices already available in the system. The voltage control issue turns out to be a very challenging problem for the distribution engineers since existing control coordination schemes would need to be reconsidered to take into account the DG operation. In this paper, we propose a control coordination technique, which is able to utilize the ability of DG as a voltage regulator and, at the same time, minimize interaction with other active devices, such as an on-load tap changing transformer and a voltage regulator. The technique has been developed based on the concept of control zone, line drop compensation, dead band, as well as the choice of controllers' parameters. Simulations carried out on an Australian system show that the technique is suitable and flexible for any system with multiple regulating devices including DG.