718 research outputs found

    Site α Is Crucial for Two Routes of IFNγ-Induced MHC Class I Transactivation: The ISRE-Mediated Route and a Novel Pathway Involving CIITA

    Get PDF
    AbstractThe constitutive and cytokine-induced levels of major histocompatibility (MHC) class I expression are tightly controlled at the transcriptional level. In this study, it is shown that the cis-acting regulatory element site α of the MHC class I promoter is essential for the IFNγ-induced transactivation of MHC class I gene expression through the ISRE. Moreover, it was discovered that the class II transactivator (CIITA), which is itself under the control of the IFNγ induction pathway, strongly transactivates MHC class I gene expression and exerts its activity through site α. Therefore, site α is a crucial regulatory element, mediating the classic route of IFNγ induction via the ISRE as well as a novel route of MHC class I transactivation involving CIITA

    Health Considerations Regarding Horizontal Transfer of Microbial Transgenes Present in Genetically Modified Crops

    Get PDF
    The potential effects of horizontal gene transfer on human health are an important item in the safety assessment of genetically modified organisms. Horizontal gene transfer from genetically modified crops to gut microflora most likely occurs with transgenes of microbial origin. The characteristics of microbial transgenes other than antibiotic-resistance genes in market-approved genetically modified crops are reviewed. These characteristics include the microbial source, natural function, function in genetically modified crops, natural prevalence, geographical distribution, similarity to other microbial genes, known horizontal transfer activity, selective conditions and environments for horizontally transferred genes, and potential contribution to pathogenicity and virulence in humans and animals. The assessment of this set of data for each of the microbial genes reviewed does not give rise to health concerns. We recommend including the above-mentioned items into the premarket safety assessment of genetically modified crops carrying transgenes other than those reviewed in the present study

    Finite Minds and Open Minds

    Get PDF
    One of the most persistent complaints about Peter Klein’s infinitism involves the finite mind objection: given that we are finite, how can we ever handle an infinite series of reasons? Klein’s answer has been that we need not actually produce an infinite series; it is enough that such a series be available to us. In this paper a different reply is presented through the reconstruction of epistemic justification as a trade-off. In acting as responsible agents, we are striking a balance between the number of reasons that we can handle and the level of precision that we want our beliefs to have. If we are unable or unwilling to manage a large number of reasons, then we have to pay the price in terms of justificatory inexactitude and thereby of accepting relatively untrustworthy beliefs. As well as being intuitively attractive, this idea of a trade-off is warranted by the mathematics of epistemic justification, understood as involving probabilistic relations

    Синкретизм квантитативних конструювань (на матеріалі числівників англійської мови)

    Get PDF
    У статті осмислюється явище синкретизму на матеріалі англійських квантитативних слів, нумеральних і денумеральних словосполучень. Мають місце порівняння з димензіональною лексико. Синкрети розглядаються на матеріалі синкретсемії. Актуальність теми мотивується зростаючим інтересом учених до нової наукової парадигми – синергетики.Объектом исследования является феномен синкретизма на материале квантитативных единиц в модусах языка, речи и речевого поведения (предмет исследования). Цель исследования состоит в осмыслении упомянутой парадигмы, ее идей, процессов самоорганизации и саморазвития. В работе верифицируются гипотезы: - номинативные единицы являются билатеральными и синкретичными; - их системная организация и эволюция интегрируется триадой материала, энергии, информации; - основным методологическим механизмом является онтогносиологический подход к исследуемым референтам. Ценным вкладом в синергетику представляется дальнейшая разработка основных положений и понятий новой научной парадигмы – лингвосинергетики.The article in question deals with the English quantitative units, i.e. numerals, numeric words, on the one hand, and dimension units – words of weight and measure, on the other hand. This object is dealt with in the endozones of language, speech and speech behaviour. The aim of investigation consists in identification of the markers of systematic arrangement of the paradigm – its selforganization and evolution: - verification of hypotheses that: - bilateral and syncretic; - aspects of words go together; - incorporated subject mater, energy and information of syncretas make the triad go; - ontognosiological method is at work. Topicality of the theme is objectivized by the growing interest to the problem by scientists of this country and abroad. This is a new scientific paradigm (synergetics), let alone many a lacunar items within its domain. Valour scenes remain undiscovered yet and await their solution in terms of mayor ideas and categories. Lacunarity is indebted to the process of cognition, cognized and non-cognized phenomenas. The choise of complex ontognosiological approach is determined by the nature of referents. Missing items come into being due to the problem of nothingness. The syncretas come archaic due to losses in the vocabulary or fall out of concepts. Some words are prohibited by taboo. Some syncretas work in the speech behaviour (silence, hesitation, pauses)

    Feasibility of a liver transcriptomics approach to assess bovine treatment with the prohormone dehydroepiandrosterone (DHEA)

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Within the European Union the use of growth promoting agents in animal production is prohibited. Illegal use of natural prohormones like dehydroepiandrosterone (DHEA) is hard to prove since prohormones are strongly metabolized <it>in vivo</it>. In the present study, we investigated the feasibility of a novel effect-based approach for monitoring abuse of DHEA. Changes in gene expression profiles were studied in livers of bull calves treated orally (PO) or intramuscularly (IM) with 1000 mg DHEA versus two control groups, using bovine 44K DNA microarrays. In contrast to controlled genomics studies, this work involved bovines purchased at the local market on three different occasions with ages ranging from 6 to 14 months, thereby reflecting the real life inter-animal variability due to differences in age, individual physiology, season and diet.</p> <p>Results</p> <p>As determined by principal component analysis (PCA), large differences in liver gene expression profiles were observed between treated and control animals as well as between the two control groups. When comparing the gene expression profiles of PO and IM treated animals to that of all control animals, the number of significantly regulated genes (p-value <0.05 and a fold change >1.5) was 23 and 37 respectively. For IM and PO treated calves, gene sets were generated of genes that were significantly regulated compared to one control group and validated versus the other control group using Gene Set Enrichment Analysis (GSEA). This cross validation, showed that 6 out of the 8 gene sets were significantly enriched in DHEA treated animals when compared to an 'independent' control group.</p> <p>Conclusions</p> <p>This study showed that identification and application of genomic biomarkers for screening of (pro)hormone abuse in livestock production is substantially hampered by biological variation. On the other hand, it is demonstrated that comparison of pre-defined gene sets versus the whole genome expression profile of an animal allows to distinguish DHEA treatment effects from variations in gene expression due to inherent biological variation. Therefore, DNA-microarray expression profiling together with statistical tools like GSEA represent a promising approach to screen for (pro)hormone abuse in livestock production. However, a better insight in the genomic variability of the control population is a prerequisite in order to define growth promoter specific gene sets that can be used as robust biomarkers in daily practice.</p

    Species-dependent responses of crop plants to polystyrene microplastics

    Get PDF
    Abstract: Only recently there has been a strong focus on the impacts of microplastics on terrestrial crop plants. This study aims to examine and compare the effects of microplastics on two monocotyledonous (barley, Hordeum vulgare and wheat, Triticum aestivum), and two dicotyledonous (carrot, Daucus carota and lettuce, Lactuca sativa) plant species through two complimentary experiments. First, we investigated the effects of low, medium, and high (103, 105, 107 particles per mL) concentrations of 500 nm polystyrene microplastics (PS-MPs) on seed germination and early development. We found species-dependent effects on the early development, with microplastics only significantly affecting lettuce and carrot. When acutely exposed during germination, PS-MPs significantly delayed the germination of lettuce by 24%, as well as promoted the shoot growth of carrot by 71% and decreased its biomass by 26%. No effect was recorded on monocot species. Secondly, we performed a chronic (21 d) hydroponic experiment on lettuce and wheat. We observed that PS-MPs significantly reduced the shoot growth of lettuce by up to 35% and increased its biomass by up to 64%, while no record was reported on wheat. In addition, stress level indicators and defence mechanisms were significantly up-regulated in both lettuce and wheat seedlings. Overall, this study shows that PS-MPs affect plant development: impacts were recorded on both germination and growth for dicots, and responses identified by biochemical markers of stress were increased in both lettuce and wheat. This highlights species-dependent effects as the four crops were grown under identical conditions to allow direct comparison. For future research, our study emphasizes the need to focus on crop specific effects, while also working towards knowledge of plastic-induced impacts at environmentally relevant conditions
    corecore