917 resultados para Embryo viability


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White light strongly promotes dormancy in freshly harvested cereal grains, whereas dark and after-ripening have the opposite effect. We have analyzed the interaction of light and after-ripening on abscisic acid (ABA) and gibberellin (GA) metabolism genes and dormancy in barley (Hordeum vulgare ‘Betzes’). Analysis of gene expression in imbibed barley grains shows that different ABA metabolism genes are targeted by white light and after-ripening. Of the genes examined, white light promotes the expression of an ABA biosynthetic gene, HvNCED1, in embryos. Consistent with this result, enzyme-linked immunosorbent assays show that dormant grains imbibed under white light have higher embryo ABA content than grains imbibed in the dark. After-ripening has no effect on expression of ABA biosynthesis genes, but promotes expression of an ABA catabolism gene (HvABA8′OH1), a GA biosynthetic gene (HvGA3ox2), and a GA catabolic gene (HvGA2ox3) following imbibition. Blue light mimics the effects of white light on germination, ABA levels, and expression of GA and ABA metabolism genes. Red and far-red light have no effect on germination, ABA levels, or HvNCED1. RNA interference experiments in transgenic barley plants support a role of HvABA8′OH1 in dormancy release. Reduced HvABA8′OH1 expression in transgenic HvABA8′OH1 RNAi grains results in higher levels of ABA and increased dormancy compared to nontransgenic grains.

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Cancer-associated proteases promote peritoneal dissemination and chemoresistance in malignant progression. In this study, kallikrein-related peptidases 4, 5, 6, and 7 (KLK4-7)-cotransfected OV-MZ-6 ovarian cancer cells were embedded in a bioengineered three-dimensional (3D) microenvironment that contains RGD motifs for integrin engagement to analyze their spheroid growth and survival after chemotreatment. KLK4-7-cotransfected cells formed larger spheroids and proliferated more than controls in 3D, particularly within RGD-functionalized matrices, which was reduced upon integrin inhibition. In contrast, KLK4-7-expressing cell monolayers proliferated less than controls, emphasizing the relevance of the 3D microenvironment and integrin engagement. In a spheroid-based animal model, KLK4-7-overexpression induced tumor growth after 4 weeks and intraperitoneal spread after 8 weeks. Upon paclitaxel administration, KLK4-7-expressing tumors declined in size by 91% (controls: 87%) and showed 90% less metastatic outgrowth (controls: 33%, P<0.001). KLK4-7-expressing spheroids showed 53% survival upon paclitaxel treatment (controls: 51%), accompanied by enhanced chemoresistance-related factors, and their survival was further reduced by combination treatment of paclitaxel with KLK4/5/7 (22%, P=0.007) or MAPK (6%, P=0.006) inhibition. The concomitant presence of KLK4-7 in ovarian cancer cells together with integrin activation drives spheroid formation and proliferation. Combinatorial approaches of paclitaxel and KLK/MAPK inhibition may be more efficient for late-stage disease than chemotherapeutics alone as these inhibitory regimens reduced cancer spheroid growth to a greater extent than paclitaxel alone.

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Shanghai possesses an apt legacy, once referred to as “Paris of the East”. Municipal aspirations for Shanghai to assume a position among the great fashion cities of the world have been integrated in the recent re-shaping of this modern city into a role model for Chinese creative enterprise yet China is still known primarily as centre of clothing production. Increasingly however, “Made in China” is being replaced by “Created in China” drawing attention to two distinct consumer markets for Chinese designers. Fashion designers who have entered the global fashion system for education or by showing their collections have generally adopted a design aesthetic that aligns with Western markets, allowing little competitive advantage. In contrast, Chinese designers who rest their attention on the domestic Chinese market find a disparate, highly competitive marketplace. The pillars of authenticity that for foreign fashion brands extend far into their cultural and creative histories, often for many decades in the case of Louis Vuitton, Hermes and Christian Dior do not yet exist in China in this era of rapid globalisation. Here, the cultural bedrock allows these same pillars to extend only thirty years or so into the past reaching the moments when Deng Xiaoping granted China’s creative entrepreneurs passage. To this end, interviews with fashion designers in Shanghai have been undertaken during the last twelve months for a PhD dissertation. Production of culture theory has been used to identify working methods, practices of production and the social and cultural milieu necessary for designers to achieve viability.

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Introduction. Stem cells are regularly cultured under normoxic conditions. However, the physiological oxygen tension in the stem cell niche is known to be as low as 1-2% oxygen, suggesting that hypoxia has a distinct impact on stem cell maintenance. Periodontal ligament cells (PDLCs) and dental pulp cells (DPCs) are attractive candidates in dental tissue regeneration. It is of great interest to know whether hypoxia plays a role in maintaining the stemness and differentiation capacity of PDLCs and DPCs. Methods. PDLCs and DPCs were cultured either in normoxia (20% O2) or hypoxia (2% O2). Cell viability assays were performed and the expressions of pluripotency markers (Oct-4, Sox2, and c-Myc) were detected by qRT-PCR and western blotting. Mineralization, glycosaminoglycan (GAG) deposition, and lipid droplets formation were assessed by Alizarin red S, Safranin O, and Oil red O staining, respectively. Results. Hypoxia did not show negative effects on the proliferation of PDLCs and DPCs. The pluripotency markers and differentiation potentials of PDLCs and DPCs significantly increased in response to hypoxic environment. Conclusions. Our findings suggest that hypoxia plays an important role in maintaining the stemness and differentiation capacity of PDLCs and DPCs.

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Estrogen receptor (ER)-β has been shown to possess a tumor suppressive effect, and is a potential target for cancer therapy. Using gene-expression meta-analysis of human malignant pleural mesothelioma, we identified an ESR2 (ERβ coding gene) signature. High ESR2 expression was strongly associated with low succinate dehydrogenase B (SDHB) (which encodes a mitochondrial respiratory chain complex II subunit) expression. We demonstrate that SDHB loss induced ESR2 expression, and that activated ERβ, by over-expression or by selective agonist stimulation, negatively affected oxidative phosphorylation compromising mitochondrial complex II and IV activity. This resulted in reduced mitochondrial ATP production, increased glycolysis dependence and impaired cell proliferation. The observed in vitro effects were phenocopied in vivo using a selective ERβ agonist in a mesothelioma mouse model. On the whole, our data highlight an unforeseen interaction between ERβ-mediated tumor suppression and energy metabolism that may be exploited to improve on the therapy for clinical management of malignant mesothelioma.

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Non-small cell lung carcinoma remains by far the leading cause of cancer-related deaths worldwide. Overexpression of FLIP, which blocks the extrinsic apoptotic pathway by inhibiting caspase-8 activation, has been identified in various cancers. We investigated FLIP and procaspase-8 expression in NSCLC and the effect of HDAC inhibitors on FLIP expression, activation of caspase-8 and drug resistance in NSCLC and normal lung cell line models. Immunohistochemical analysis of cytoplasmic and nuclear FLIP and procaspase-8 protein expression was carried out using a novel digital pathology approach. Both FLIP and procaspase-8 were found to be significantly overexpressed in tumours, and importantly, high cytoplasmic expression of FLIP significantly correlated with shorter overall survival. Treatment with HDAC inhibitors targeting HDAC1-3 downregulated FLIP expression predominantly via post-transcriptional mechanisms, and this resulted in death receptor- and caspase-8-dependent apoptosis in NSCLC cells, but not normal lung cells. In addition, HDAC inhibitors synergized with TRAIL and cisplatin in NSCLC cells in a FLIP- and caspase-8-dependent manner. Thus, FLIP and procaspase-8 are overexpressed in NSCLC, and high cytoplasmic FLIP expression is indicative of poor prognosis. Targeting high FLIP expression using HDAC1-3 selective inhibitors such as entinostat to exploit high procaspase-8 expression in NSCLC has promising therapeutic potential, particularly when used in combination with TRAIL receptor-targeted agents.

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Current routine cell culture techniques are only poorly suited to capture the physiological complexity of tumor microenvironments, wherein tumor cell function is affected by intricate three-dimensional (3D), integrin-dependent cell-cell and cell-extracellular matrix (ECM) interactions. 3D cell cultures allow the investigation of cancer-associated proteases like kallikreins as they degrade ECM proteins and alter integrin signaling, promoting malignant cell behaviors. Here, we employed a hydrogel microwell array platform to probe using a high-throughput mode how ovarian cancer cell aggregates of defined size form and survive in response to the expression of kallikreins and treatment with paclitaxel, by performing microscopic, quantitative image, gene and protein analyses dependent on the varying microwell and aggregate sizes. Paclitaxel treatment increased aggregate formation and survival of kallikrein-expressing cancer cells and levels of integrins and integrin-related factors. Cancer cell aggregate formation was improved with increasing aggregate size, thereby reducing cell death and enhancing integrin expression upon paclitaxel treatment. Therefore, hydrogel microwell arrays are a powerful tool to screen the viability of cancer cell aggregates upon modulation of protease expression, integrin engagement and anti-cancer treatment providing a micro-scaled yet high-throughput technique to assess malignant progression and drug-resistance.

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We appreciate Holmes' body of work relating to transitions within the Australian landscape, and welcome the opportunity to engage in a discussion on this topic. The paper to which Holmes refers (Bjørkhaug and Richards, 2008) examined the application of agricultural (rather than landscape) multifunctionality in both Norway and Australia. Of specific focus was how non-tradeable concerns, such as environmental sustainability, faired under these divergent systems. We argued that Norway's multifunctionality was strong, due to it being embraced at both the policy and actor level, whereas Australia's could be described as weak. This ‘weak multifunctionality’ that we observed in Australia was due to an emerging bi-lateral (state and federal) policy framework that advocated the importance of environmental values which was rarely embraced by landholders who found themselves trapped on the ‘agricultural treadmill’. The nature of the treadmill is that alternative forms of land use are unthinkable when on-farm investments have been made that support the status quo – to get bigger and/or more efficient. For many of the Australian landholders interviewed in relation to this study, efficiency in production was at odds with the values necessary to effect a transition toward multifunctionality. For instance, graziers in Central Queensland were unconvinced of the value of conserving native flora and fauna when economic viability can be better assured through clear felling native forests to increase the productive capacity of the land.

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The statement. 'it is hard to be green when you are in the red' is commonly used by primary producers to explain the necessity of placing a greater emphasis on financial survival rather than longer term environmental sustainability. The subject of environmental sustainability on pastoral properties was explored during face-to:face interviews with cattle grazers in the Fitzroy Basin area of Central Queensland. Findings from the study suggest that while economic factors are important, they are not the only determinant in whether a landholder priorities environmental sustainability, Rather. social factors such as knowledge claims. beliefs, attitudes. values, peer pressure and social sanctioning, constructed and enacted within the productivist paradigm of primary production. play a crucial role in how landholders manage their natural assets. This suggests that the edict that 'It is hard to be green when you are in the red' is inaccurate and does not explain why conservation-focused pastoral management is not yet occurring on a large scale.

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The ‘war on terror’ and ongoing terrorist attacks around the world have generated a growing body of literature on national and international measures to counteract terrorist activity. This detailed study investigates an aspect of contemporary counter-terrorism that has been largely overlooked; the impact of these measures on the continued viability of the democratic state.

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The measures by which major developments are officially approved for construction are - by common agreement - complex, time-consuming, and of questionable merit in terms of maintaining ecological viability.

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Purpose Managing and maintaining infrastructure assets are one of the indispensible tasks for many government agencies to preserve the nations' economic viability and social welfare. To reduce the expenditures over the life-cycle of an infrastructure asset and extend the period for which the asset performs effectively, proper repair and maintenance are essential. While repair, maintenance, minor alteration and addition (RMAA) sector is expanding in many developed cities, occurrences of fatalities and injuries in this sector are also soaring. The purposes of this paper are to identify and then evaluate the various strategies for improving the safety performance of RMAA works. Design/methodology/approach Semi-structured interviews and two rounds of Delphi survey were conducted for data collection. Findings Raising safety awareness of RMAA workers and selecting contractors with a good record of safety performance are the two most important strategies to improve the safety performance in this sector. Technology innovations and a pay-for-safety scheme are regarded as the two least important strategies. Originality/value The paper highlights possible ways to enhance safety of the rather under-explored RMAA sector in the construction industry.

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Constant changes in the global economic environment require companies to revisit traditional assumptions about how businesses create and capture value (Teece, 2010). In recent years, management practice literature has focused largely on better understanding business models and business model innovation (Amit, Zott and Massa, 2010; Johnson, Christensen and Kagermann, 2008). Much has been written on the benefits of linking design and design thinking to organisational strategies and business transformation. However, very little has been researched and reported on regarding the impact of design led approaches to triple bottom-line opportunities such as, social innovation enterprise. In the context of this paper Design Led Innovation is defined as the tools and approaches which enable design thinking to be embedded as an element of cultural transformation within a business. Being Design Led requires a company to have a vision for top line growth founded on deep customer insights and expanded through customer and stakeholder engagements. The outcomes of this are then mapped to all aspects of the business, enabling the vision to be successfully implemented and achieved. It is the latter part of this definition where we believe Design Led Innovation has the greatest value in transforming social innovation enterprise into a sustainable business venture. However, we also acknowledge that enabling these firms to think strategically about their business model is difficult given the unique operational and funding challenges that often characterize many social enterprises. The purpose of this paper, therefore, is to pose the question, do sustainable innovation enterprise innovate their business model? And if so, how? It is the authors’ opinion that such enterprises only innovate at the product or system level without a complete understanding of the business model structure, which underpins the long term viability. However, in this paper we challenge this notion and explore if such firms can overcome their size and operational constraints to become sustainable enterprises using a design led approach. This is achieved through contextualizing business model innovation, briefly defining social innovation enterprise and profiling a new and emerging industry in Australia – Clean Technology. Future research challenges and opportunities are also presented.

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Highway construction works have significant bearings on all aspects of sustainability. With the increasing level of public awareness and government regulatory measures, the construction industry is experiencing a cultural shift to recognise, embrace and pursue sustainability. Stakeholders are now keen to identify sustainable alternatives and the financial implications of including them on a lifecycle basis. They need tools that can aid the evaluation of investment options. To date, however, there have not been many financial assessments on the sustainability aspects of highway projects. This is because the existing life-cycle costing analysis (LCCA) models tend to focus on economic issues alone and are not able to deal with sustainability factors. This paper provides insights into the current practice of life-cycle cost analysis, and the identification and quantification of sustainability-related cost components in highway projects through literature review, questionnaire surveys and semi-structured interviews. The results can serve as a platform for highway project stakeholders to develop practical tools to evaluate highway investment decisions and reach an optimum balance between financial viability and sustainability deliverables.

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In coastal areas, extreme weather events, such as floods and cyclones, can have debilitating effects on the social and economic viability of marine-based industries. In March 2011, the Great Barrier Reef Marine Park Authority implemented an Extreme Weather Response Program, following a period of intense flooding and cyclonic activity between December 2010 and February 2011. In this paper, we discuss the results of a project within the Program, which aimed to: (1) assess the impacts of extreme weather events on regional tourism and commercial fishing industries; and (2) develop and road-test an impact assessment matrix to improve government and industry responses to extreme weather events. Results revealed that extreme weather events both directly and indirectly affected all five of the measured categories, i.e. ecological, personal, social, infrastructure and economic components. The severity of these impacts, combined with their location and the nature of their business, influenced how tourism operators and fishers assessed the impact of the events (low, medium, high or extreme). The impact assessment tool was revised following feedback obtained during stakeholder workshops and may prove useful for managers in responding to potential direct and indirect impacts of future extreme weather events on affected marine industries. © 2013 Planning Institute Australia.