154 research outputs found

    DNA crosslinking and biological activity of a hairpin polyamide–chlorambucil conjugate

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    A prototype of a novel class of DNA alkylating agents, which combines the DNA crosslinking moiety chlorambucil (Chl) with a sequence-selective hairpin pyrrole-imidazole polyamide ImPy-beta-ImPy-gamma-ImPy-beta-Dp (polyamide 1), was evaluated for its ability to damage DNA and induce biological responses. Polyamide 1-Chl conjugate (1-Chl) alkylates and interstrand crosslinks DNA in cell-free systems. The alkylation occurs predominantly at 5'-AGCTGCA-3' sequence, which represents the polyamide binding site. Conjugate-induced lesions were first detected on DNA treated for 1 h with 0.1 muM 1-Chl, indicating that the conjugate is at least 100-fold more potent than Chl. Prolonged incubation allowed for DNA damage detection even at 0.01 muM concentration. Treatment with 1-Chl decreased DNA template activity in simian virus 40 (SV40) in vitro replication assays. 1-Chl inhibited mammalian cell growth, genomic DNA replication and cell cycle progression, and arrested cells in the G(2)/M phase. Moreover, cellular effects were observed at 1-Chl concentrations similar to those needed for DNA damage in cell-free systems. Neither of the parent compounds, unconjugated Chl or polyamide 1, demonstrated any cellular activity in the same concentration range. The conjugate molecule 1-Chl possesses the sequence-selectivity of a polyamide and the enhanced DNA reactivity of Chl

    NuA4 and H2A.Z control environmental responses and autotrophic growth in Arabidopsis.

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    Nucleosomal acetyltransferase of H4 (NuA4) is an essential transcriptional coactivator in eukaryotes, but remains poorly characterized in plants. Here, we describe Arabidopsis homologs of the NuA4 scaffold proteins Enhancer of Polycomb-Like 1 (AtEPL1) and Esa1-Associated Factor 1 (AtEAF1). Loss of AtEAF1 results in inhibition of growth and chloroplast development. These effects are stronger in the Atepl1 mutant and are further enhanced by loss of Golden2-Like (GLK) transcription factors, suggesting that NuA4 activates nuclear plastid genes alongside GLK. We demonstrate that AtEPL1 is necessary for nucleosomal acetylation of histones H4 and H2A.Z by NuA4 in vitro. These chromatin marks are diminished genome-wide in Atepl1, while another active chromatin mark, H3K9 acetylation (H3K9ac), is locally enhanced. Expression of many chloroplast-related genes depends on NuA4, as they are downregulated with loss of H4ac and H2A.Zac. Finally, we demonstrate that NuA4 promotes H2A.Z deposition and by doing so prevents spurious activation of stress response genes

    Imidazoacridinone-dependent lysosomal photodestruction: a pharmacological Trojan horse approach to eradicate multidrug-resistant cancers

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    Multidrug resistance (MDR) remains a primary hindrance to curative cancer therapy. Thus, introduction of novel strategies to overcome MDR is of paramount therapeutic significance. Sequestration of chemotherapeutics in lysosomes is an established mechanism of drug resistance. Here, we show that MDR cells display a marked increase in lysosome number. We further demonstrate that imidazoacridinones (IAs), which are cytotoxic fluorochromes, undergo a dramatic compartmentalization in lysosomes because of their hydrophobic weak base nature. We hence developed a novel photoactivation-based pharmacological Trojan horse approach to target and eradicate MDR cancer cells based on photo-rupture of IA-loaded lysosomes and tumor cell lysis via formation of reactive oxygen species. Illumination of IA-loaded cells resulted in lysosomal photodestruction and restoration of parental cell drug sensitivity. Lysosomal photodestruction of MDR cells overexpressing the key MDR efflux transporters ABCG2, ABCB1 or ABCC1 resulted in 10- to 52-fold lower IC(50) values of various IAs, thereby restoring parental cell sensitivity. Finally, in vivo application of this photodynamic therapy strategy after i.v. injection of IAs in human ovarian tumor xenografts in the chorioallantoic membrane model revealed selective destruction of tumors and their associated vasculature. These findings identify lysosomal sequestration of IAs as an Achilles heel of MDR cells that can be harnessed to eradicate MDR tumor cells via lysosomal photodestruction

    Decision aids for respite service choices by carers of people with dementia: development and pilot RCT

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    <p>Abstract</p> <p>Background</p> <p>Decision aids are often used to assist individuals confronted with a diagnosis of a serious illness to make decisions about treatment options. However, they are rarely utilised to help those with chronic or age related conditions to make decisions about care services. Decision aids should also be useful for carers of people with decreased decisional capacity. These carers' choices must balance health outcomes for themselves and for salient others with relational and value-based concerns, while relying on information from health professionals. This paper reports on a study that both developed and pilot tested a decision aid aimed at assisting carers to make evaluative judgements of community services, particularly respite care.</p> <p>Methods</p> <p>A mixed method sequential study, involving qualitative development and a pilot randomised controlled trial, was conducted in Tasmania, Australia. We undertook 13 semi-structured interviews and three focus groups to inform the development of the decision aid. For the randomised control trial we randomly assigned 31 carers of people with dementia to either receive the service decision aid at the start or end of the study. The primary outcome was measured by comparing the difference in carer burden between the two groups three months after the intervention group received the decision aid. Pilot data was collected from carers using interviewer-administered questionnaires at the commencement of the project, two weeks and 12 weeks later.</p> <p>Results</p> <p>The qualitative data strongly suggest that the intervention provides carers with needed decision support. Most carers felt that the decision aid was useful. The trial data demonstrated that, using the mean change between baseline and three month follow-up, the intervention group had less increase in burden, a decrease in decisional conflict and increased knowledge compared to control group participants.</p> <p>Conclusions</p> <p>While these results must be interpreted with caution due to the small sample size, all intervention results trend in a direction that is beneficial for carers and their decisional ability. Mixed method data suggest the decision aid provides decisional support that carers do not otherwise receive. Decision aids may prove useful in a community health services context.</p> <p>Trial registration number</p> <p>ISRCTN: <a href="http://www.controlled-trials.com/ISRCTN32163031">ISRCTN32163031</a></p

    An international collaborative evaluation of central serous chorioretinopathy: different therapeutic approaches and review of literature. The European Vitreoretinal Society central serous chorioretinopathy study

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    Purpose: To study and compare the efficacy of different therapeutic options for the treatment of central serous chorioretinopathy (CSCR). Methods: This is a nonrandomized, international multicentre study on 1719 patients (1861 eyes) diagnosed with CSCR, from 63 centres (24 countries). Reported data included different methods of treatment and both results of diagnostic examinations [fluorescein angiography and/or optical coherent tomography (OCT)] and best-corrected visual acuity (BCVA) before and after therapy. The duration of observation had a mean of 11&nbsp;months but was extended in a minority of cases up to 7&nbsp;years. The aim of this study is to evaluate the efficacy of the different therapeutic options of CSCR in terms of both visual (BCVA) and anatomic (OCT) improvement. Results: One thousand seven hundred nineteen patients (1861 eyes) diagnosed with CSCR were included. Treatments performed were nonsteroidal anti-inflammatory eye drops, laser photocoagulation, micropulse diode laser photocoagulation, photodynamic therapy (PDT; Standard PDT, Reduced-dose PDT, Reduced-fluence PDT), intravitreal (IVT) antivascular endothelial growth factor injection (VEGF), observation and other treatments. The list of the OTHERS included both combinations of the main proposed treatments or a variety of other treatments such as eplerenone, spironolactone, acetazolamide, beta-blockers, anti-anxiety drugs, aspirin, folic acid, methotrexate, statins, vitis vinifera extract medication and pars plana vitrectomy. The majority of the patients were men with a prevalence of 77%. The odds ratio (OR) showed a partial or complete resolution of fluid on OCT with any treatment as compared with observation. In univariate analysis, the anatomical result (improvement in subretinal fluid using OCT at 1&nbsp;month) was favoured by age &lt;60&nbsp;years (p&nbsp;&lt;&nbsp;0.005), no previous observation (p&nbsp;&lt;&nbsp;0.0002), duration less than 3&nbsp;months (p&nbsp;&lt;&nbsp;0.0001), absence of CSCR in the fellow eye (p&nbsp;=&nbsp;0.04), leakage outside of the arcade (p&nbsp;=&nbsp;0.05) and fluid height &gt;500&nbsp;\u3bcm (p&nbsp;=&nbsp;0.03). The OR for obtaining partial or complete resolution showed that anti-VEGF and eyedrops were not statistically significant; whereas PDT (8.5), thermal laser (11.3) and micropulse laser (8.9) lead to better anatomical results with less variability. In univariate analysis, the functional result at 1&nbsp;month was favoured by first episode (p&nbsp;=&nbsp;0.04), height of subretinal fluid &gt;500&nbsp;\u3bcm (p&nbsp;&lt;&nbsp;0.0001) and short duration of observation (p&nbsp;=&nbsp;0.02). Finally, there was no statistically significant difference among the treatments at 12&nbsp;months. Conclusion: Spontaneous resolution has been described in a high percentage of patients. Laser (micropulse and thermal) and PDT seem to lead to significant early anatomical improvement; however, there is little change beyond the first month of treatment. The real visual benefit needs further clarification

    Urban futures and the code for sustainable homes

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    Copyright © 2012 ICE Publishing Ltd. Permission is granted by ICE Publishing to print one copy for personal use. Any other use of these PDF files is subject to reprint fees.A 6?6 ha (66 000 m2) regeneration site, commonly referred to as Luneside East, is to be turned from a run down, economically under-achieving area of Lancaster, UK, into a new, distinctive, vibrant, sustainable quarter of the city. As a result several aspects of water planning for 350 new homes and 8000 m2 of workspace needed to be considered before any infrastructure investment was undertaken. This included assessment of the future capacity requirements (i.e. inflows and outflows) for water infrastructure (i.e. mains water supply, wastewater disposal, rainwater storage and stormwater disposal) much of which will be located underground. This paper looks at the implications of various water management strategies on the Luneside East site (e.g. water-efficient appliances, greywater recycling and rainwater harvesting) in line with current policy measures that focus on technology changes alone (e.g. the code for sustainable homes). Based on these findings this paper outlines some basic implications for technological resilience discussed in the context of four ‘world views’ – that is, the urban futures scenarios considered in this special issue. Conclusions are drawn as to how far this can take engineers, planners and developers in understanding and planning for resilient water infrastructure within a development like Luneside East

    The Role of Sexual and Reproductive Rights in Social Work Practice

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    The understanding and promotion of sexual and reproductive rights are essential in the social work profession, not only to improve the health status of affected populations but to advocate effectively for social justice and to respond to globalized realities. This article highlights the relevance of sexual and reproductive rights in the philosophical foundation and practice of social work, emphasizes the impact of reproductive health and rights on women's lives, and proposes a social work agenda that will embrace and promote sexual and reproductive rights. It uses policy statements from the International Federation of Social Workers as well as a human rights framework focused on sexual and reproductive rights that stems from the global feminist movement.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

    Elasticity of furniture elements glue by layers

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    Соответствующие исследования охватывали послойно склеиваемую буковую древесину предназначенную на выбранные конструкционные мебельные элементы. Целью исследований было определение упругостных свойств этих элементов совместно с определением зависимости между модулями упругости послойно склеиваемых элементов с различным числом слоев, их толщины и направления сгиба. Для достижения указанной цели проводились теоретические исследования с последующей проверкой на основании результатов экспериментальных изысканий. Проведенные анализы показали, что модуль упругости элементов из буковой древесины склеиваемой послойно не зависит от числа слоев ни от вида используемого клея. Примерно так же представляются прочность и деформации.The respective investigations comprised the beech wood glued by layers, designed for selected constructional furniture elements. The aim of the investigations was to determine elastic properties of the wooden elements jointly with datermination of relationships between the elasticity modules of the by-layer glued elements of different number of layers, their thickness and bending direction. To attain this aim, theoretical investigations were carried out with their subselent verification on the basis of the experimental investigation results. The investigations have proved that the elasticity module of beech wood elements glued by layers does not depend on the number of layers and the glue kind used. Strength and deformations are formed similarly
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