135 resultados para photosynthetic organisms


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Early detection of plant transformation events is necessary for the rapid establishment and optimization of plant transformation protocols. We have assessed modified versions of the green fluorescent protein (GFP) from Aequorea victoria as early reporters of plant transformation using a dissecting fluorescence microscope with appropriate filters. Gfp-expressing cells from four different plant species (sugarcane, maize, lettuce, and tobacco) were readily distinguished, following either Agrobacterium-mediated or particle bombardment-mediated transformation. The identification of gfp-expressing sugarcane cells allowed for the elimination of a high proportion of non-expressing explants and also enabled visual selection of dividing transgenic cells, an early step in the generation of transgenic organisms. The recovery of transgenic cell clusters was streamlined by the ability to visualize gfp-expressing tissues in vitro.

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Biological systems are typically complex and adaptive, involving large numbers of entities, or organisms, and many-layered interactions between these. System behaviour evolves over time, and typically benefits from previous experience by retaining memory of previous events. Given the dynamic nature of these phenomena, it is non-trivial to provide a comprehensive description of complex adaptive systems and, in particular, to define the importance and contribution of low-level unsupervised interactions to the overall evolution process. In this chapter, the authors focus on the application of the agent-based paradigm in the context of the immune response to HIV. Explicit implementation of lymph nodes and the associated lymph network, including lymphatic chain structure, is a key objective, and requires parallelisation of the model. Steps taken towards an optimal communication strategy are detailed.

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The development of whole-body imaging at single-cell resolution enables system-level approaches to studying cellular circuits in organisms. Previous clearing methods focused on homogenizing mismatched refractive indices of individual tissues, enabling reductions in opacity but falling short of achieving transparency. Here, we show that an aminoalcohol decolorizes blood by efficiently eluting the heme chromophore from hemoglobin. Direct transcardial perfusion of an aminoalcohol-containing cocktail that we previously termed CUBIC coupled with a 10 day to 2 week clearing protocol decolorized and rendered nearly transparent almost all organs of adult mice as well as the entire body of infant and adult mice. This CUBIC-perfusion protocol enables rapid whole-body and whole-organ imaging at single-cell resolution by using light-sheet fluorescent microscopy. The CUBIC protocol is also applicable to 3D pathology, anatomy, and immunohistochemistry of various organs. These results suggest that whole-body imaging of colorless tissues at high resolution will contribute to organism-level systems biology.

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Polybrominated diphenyl ethers (PBDEs), a common class of brominated flame retardants, are a ubiquitous part of our built environment, and for many years have contributed to improved public safety by reducing the flammability of everyday goods. Recently, PBDEs have come under increased international attention because of their potential to impact upon the environment and human health. Some PBDE compounds have been nominated for possible inclusion on the Stockholm Convention on Persistent Organic Pollutants, to which Australia is a Party. Work under the Stockholm Convention has demonstrated the capacity of some PBDEs to persist and accumulate in the environment and to be carried long distances. Much is unknown about the impact of PBDEs on living organisms, however recent studies show that some PBDEs can inhibit growth in colonies of plankton and algae and depress the reproduction of zooplankton. Laboratory mice and rats have also shown liver disturbances and damage to developing nervous systems as a result of exposure to PBDEs. In 2004, the Australian Government Department of the Environment and Water Resources began three studies to examine levels of PBDEs in aquatic sediments, indoor environments and human blood, as knowledge about PBDEs in Australia was very limited. The aim of these studies was to improve this knowledge base so that governments were in a better position to consider appropriate management actions. Due to the high costs for laboratory analysis of PBDEs, the number of samples collected for each study was limited and so caution is required when interpreting the findings. Nevertheless, these studies will provide governments with an indication of how prevalent PBDEs are in the Australian population and the environment and will also contribute to international knowledge about these chemicals. The Department of the Environment and Water Resources will be working closely with othergovernment agencies, industry and the community to investigate any further action that may be required to address PBDEs in Australia.

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This project developed and assessed a standard operating procedure for monitoring microbiological aerosol levels and dispersal from Australian industrial composting facilities. Development occurred via seasonal monitoring of such operations with evaluation of optimal microbial indicator organisms, sampling and analysis logistics. The resultant procedure allows practical end-user assessment of compost-associated bioaerosol levels, and potential health risks to proximal residential populations encroaching on such composting facilities and on-site industrial operations personnel.

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To produce commercially valuable ketocarotenoids in Solanum tuberosum, the 4, 4′ β-oxygenase (crtW) and 3, 3′ β-hydroxylase (crtZ) genes from Brevundimonas spp. have been expressed in the plant host under constitutive transcriptional control. The CRTW and CRTZ enzymes are capable of modifying endogenous plant carotenoids to form a range of hydroxylated and ketolated derivatives. The host (cv. Désirée) produced significant levels of nonendogenous carotenoid products in all tissues, but at the apparent expense of the economically critical metabolite, starch. Carotenoid levels increased in both wild-type and transgenic tubers following cold storage; however, stability during heat processing varied between compounds. Subcellular fractionation of leaf tissues revealed the presence of ketocarotenoids in thylakoid membranes, but not predominantly in the photosynthetic complexes. A dramatic increase in the carotenoid content of plastoglobuli was determined. These findings were corroborated by microscopic analysis of chloroplasts. In tuber tissues, esterified carotenoids, representing 13% of the total pigment found in wild-type extracts, were sequestered in plastoglobuli. In the transgenic tubers, this proportion increased to 45%, with esterified nonendogenous carotenoids in place of endogenous compounds. Conversely, nonesterified carotenoids in both wild-type and transgenic tuber tissues were associated with amyloplast membranes and starch granules.

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Hormesis enco 16 mpasses the notion that low levels of stress stimulate or upregulate 17 existing cellular and molecular pathways that improve the capacity of cells and organisms to 18 withstand greater stress. This notion underlies much of what we know about how exercise 19 conditions the body and induces long-term adaptations. During exercise, the body is 20 exposed to various forms of stress, including thermal, metabolic, hypoxic, oxidative, and 21 mechanical stress. These stressors activate biochemical messengers, which in turn activate 22 various signaling pathways that regulate gene expression and adaptive responses. 23 Historically, antioxidant supplements, nonsteroidal anti-inflammatory drugs, and 24 cryotherapy have been favored to attenuate or counteract exercise-induced oxidative stress 25 and inflammation. However, reactive oxygen species and inflammatory mediators are key 26 signaling molecules in muscle, and such strategies may mitigate adaptations to exercise. 27 Conversely, withholding dietary carbohydrate and restricting muscle blood flow during 28 exercise may augment adaptations to exercise. In this review article, we combine, integrate, 29 and apply knowledge about the fundamental mechanisms of exercise adaptation. We also 30 critically evaluate the rationale for using interventions that target these mechanisms under 31 the overarching concept of hormesis. There is currently insufficient evidence to establish 32 whether these treatments exert dose-dependent effects on muscle adaptation. However, 33 there appears to be some dissociation between the biochemical/molecular effects and 34 functional/performance outcomes of some of these treatments. Although several of these 35 treatments influence common kinases, transcription factors and proteins, it remains to be 36 determined if these interventions complement or negate each other, and whether such 37 effects are strong enough to influence adaptations to exercise.

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In 40 febrile neutropenic episodes during the induction and consolidation chemotherapy of acute leukaemia in Riyadh, 51% of organisms causing septicaemia were gram-negative, 26% gram-positive, 8% anaerobes and 15% fungi. In 21 (52%) febrile episodes there were pulmonary infiltrates; of the 12 where aetiology was known, six were due to fungi. Pulmonary infiltrates progressed to adult respiratory distress syndrome and death in nine instances. There was no significant occurrence of parasitic and tropical infections. The results show that the pattern of infections, during therapy of acute leukaemia in developing countries, may have important differences when compared with western centres. Empiric amphotericin B may need to be introduced at an earlier stage in patients with persistent fever or progressive pulmonary infiltrates.

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The present invention relates generally to methods for diagnosing and treating infectious diseases and other conditions related thereto. More particularly, the present invention relates to methods for determining the presence of organisms of the Chlamydiaceae family in a subject, including species of Chlamydia, and to methods for determining the stage of an infection caused by such organisms. The present invention also relates to kits for use with the diagnostic methods. The methods and kits of the present invention are particularly useful in relation to human and non-human, i.e. veterinary subjects. The present invention further relates to methods for identifying proteins or nucleic acid sequences associated with chlamydial infection in a subject. Such proteins or nucleic acid sequences are not only useful in relation to the diagnostic methods of the invention but are also useful in the development of methods and agents for preventing and/or treating chlamydial infection in a subject, such as but not limited to, immunotherapeutic methods and agents.

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Canonical single-stranded DNA-binding proteins (SSBs) from the oligosaccharide/oligonucleotide-binding (OB) domain family are present in all known organisms and are critical for DNA replication, recombination and repair. The SSB from the hyperthermophilic crenarchaeote Sulfolobus solfataricus (SsoSSB) has a ‘simple’ domain organization consisting of a single DNA-binding OB fold coupled to a flexible C-terminal tail, in contrast with other SSBs in this family that incorporate up to four OB domains. Despite the large differences in the domain organization within the SSB family, the structure of the OB domain is remarkably similar all cellular life forms. However, there are significant differences in the molecular mechanism of ssDNA binding. We have determined the structure of the SsoSSB OB domain bound to ssDNA by NMR spectroscopy. We reveal that ssDNA recognition is modulated by base-stacking of three key aromatic residues, in contrast with the OB domains of human RPA and the recently discovered human homologue of SsoSSB, hSSB1. We also demonstrate that SsoSSB binds ssDNA with a footprint of five bases and with a defined binding polarity. These data elucidate the structural basis of DNA binding and shed light on the molecular mechanism by which these ‘simple’ SSBs interact with ssDNA.

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In 2009, the National Research Council of the National Academies released a report on A New Biology for the 21st Century. The council preferred the term ‘New Biology’ to capture the convergence and integration of the various disciplines of biology. The National Research Council stressed: ‘The essence of the New Biology, as defined by the committee, is integration—re-integration of the many sub-disciplines of biology, and the integration into biology of physicists, chemists, computer scientists, engineers, and mathematicians to create a research community with the capacity to tackle a broad range of scientific and societal problems.’ They define the ‘New Biology’ as ‘integrating life science research with physical science, engineering, computational science, and mathematics’. The National Research Council reflected: 'Biology is at a point of inflection. Years of research have generated detailed information about the components of the complex systems that characterize life––genes, cells, organisms, ecosystems––and this knowledge has begun to fuse into greater understanding of how all those components work together as systems. Powerful tools are allowing biologists to probe complex systems in ever greater detail, from molecular events in individual cells to global biogeochemical cycles. Integration within biology and increasingly fruitful collaboration with physical, earth, and computational scientists, mathematicians, and engineers are making it possible to predict and control the activities of biological systems in ever greater detail.' The National Research Council contended that the New Biology could address a number of pressing challenges. First, it stressed that the New Biology could ‘generate food plants to adapt and grow sustainably in changing environments’. Second, the New Biology could ‘understand and sustain ecosystem function and biodiversity in the face of rapid change’. Third, the New Biology could ‘expand sustainable alternatives to fossil fuels’. Moreover, it was hoped that the New Biology could lead to a better understanding of individual health: ‘The New Biology can accelerate fundamental understanding of the systems that underlie health and the development of the tools and technologies that will in turn lead to more efficient approaches to developing therapeutics and enabling individualized, predictive medicine.’ Biological research has certainly been changing direction in response to changing societal problems. Over the last decade, increasing awareness of the impacts of climate change and dwindling supplies of fossil fuels can be seen to have generated investment in fields such as biofuels, climate-ready crops and storage of agricultural genetic resources. In considering biotechnology’s role in the twenty-first century, biological future-predictor Carlson’s firm Biodesic states: ‘The problems the world faces today – ecosystem responses to global warming, geriatric care in the developed world or infectious diseases in the developing world, the efficient production of more goods using less energy and fewer raw materials – all depend on understanding and then applying biology as a technology.’ This collection considers the roles of intellectual property law in regulating emerging technologies in the biological sciences. Stephen Hilgartner comments that patent law plays a significant part in social negotiations about the shape of emerging technological systems or artefacts: 'Emerging technology – especially in such hotbeds of change as the life sciences, information technology, biomedicine, and nanotechnology – became a site of contention where competing groups pursued incompatible normative visions. Indeed, as people recognized that questions about the shape of technological systems were nothing less than questions about the future shape of societies, science and technology achieved central significance in contemporary democracies. In this context, states face ongoing difficulties trying to mediate these tensions and establish mechanisms for addressing problems of representation and participation in the sociopolitical process that shapes emerging technology.' The introduction to the collection will provide a thumbnail, comparative overview of recent developments in intellectual property and biotechnology – as a foundation to the collection. Section I of this introduction considers recent developments in United States patent law, policy and practice with respect to biotechnology – in particular, highlighting the Myriad Genetics dispute and the decision of the Supreme Court of the United States in Bilski v. Kappos. Section II considers the cross-currents in Canadian jurisprudence in intellectual property and biotechnology. Section III surveys developments in the European Union – and the interpretation of the European Biotechnology Directive. Section IV focuses upon Australia and New Zealand, and considers the policy responses to the controversy of Genetic Technologies Limited’s patents in respect of non-coding DNA and genomic mapping. Section V outlines the parts of the collection and the contents of the chapters.

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In response to scientific breakthroughs in biotechnology, the development of new technologies, and the demands of a hungry capitalist marketplace, patent law has expanded to accommodate a range of biological inventions. There has been much academic and public debate as to whether gene patents have a positive impact upon research and development, health-care, and the protection of the environment. In a satire of prevailing patenting practices, the English poet and part-time casino waitress, Donna MacLean, sought a patent application - GB0000180.0 - in respect of herself. She explained that she had satisfied the usual patent criteria - in that she was novel, inventive, and useful: It has taken 30 years of hard labor for me to discover and invent myself, and now I wish to protect my invention from unauthorized exploitation, genetic or otherwise. I am new: I have led a private existence and I have not made the invention of myself public. I am not obvious (2000: 18). MacLean said she had many industrial applications. ’For example, my genes can be used in medical research to extremely profitable ends - I therefore wish to have sole control of my own genetic material' (2000: 18). She observed in an interview: ’There's a kind of unpleasant, grasping, greedy atmosphere at the moment around the mapping of the human genome ... I wanted to see if a human being could protect their own genes in law' (Meek, 2000). This special issue of Law in Context charts a new era in the long-standing debate over biological inventions. In the wake of the expansion of patentable subject matter, there has been great strain placed upon patent criteria - such as ’novelty', ’inventive step', and ’utility'. Furthermore, there has been a new focus upon legal doctrines which facilitate access to patented inventions - like the defence of experimental use, the ’Bolar' exception, patent pooling, and compulsory licensing. There has been a concerted effort to renew patent law with an infusion of ethical principles dealing with informed consent and benefit sharing. There has also been a backlash against the commercialisation of biological inventions, and a call by some activists for the abolition of patents on genetic inventions. This collection considers a wide range of biological inventions - ranging from micro-organisms, plants and flowers and transgenic animals to genes, express sequence tags, and research tools, as well as genetic diagnostic tests and pharmaceutical drugs. It is thus an important corrective to much policy work, which has been limited in its purview to merely gene patents and biomedical research. This collection compares and contrasts the various approaches of a number of jurisdictions to the legal problems in respect of biological inventions. In particular, it looks at the complexities of the 1998 European Union Directive on the Legal Protection of Biotechnological Inventions, as well as decisions of member states, such as the Netherlands, and peripheral states, like Iceland. The edition considers US jurisprudence on patent law and policy, as well as recent developments in Canada. It also focuses upon recent developments in Australia - especially in the wake of parallel policy inquiries into gene patents and access to genetic resources.

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In the United States, there has been fierce debate over state, federal and international efforts to engage in genetically modified food labelling (GM food labelling). A grassroots coalition of consumers, environmentalists, organic farmers, and the food movement has pushed for law reform in respect of GM food labelling. The Just Label It campaign has encouraged United States consumers to send comments to the United States Food and Drug Administration to label genetically modified foods. This Chapter explores the various justifications made in respect of genetically modified food labelling. There has been a considerable effort to portray the issue of GM food labelling as one of consumer rights as part of ‘the right to know’. There has been a significant battle amongst farmers over GM food labelling – with organic farmers and biotechnology companies, fighting for precedence. There has also been a significant discussion about the use of GM food labelling as a form of environmental legislation. The prescriptions in GM food labelling regulations may serve to promote eco-labelling, and deter greenwashing. There has been a significant debate over whether GM food labelling may serve to regulate corporations – particularly from the food, agriculture, and biotechnology industries. There are significant issues about the interaction between intellectual property laws – particularly in respect of trade mark law and consumer protection – and regulatory proposals focused upon biotechnology. There has been a lack of international harmonization in respect of GM food labelling. As such, there has been a major use of comparative arguments about regulator models in respect of food labelling. There has also been a discussion about international law, particularly with the emergence of sweeping regional trade proposals, such as the Trans-Pacific Partnership, and the Trans-Atlantic Trade and Investment Partnership. This Chapter considers the United States debates over genetically modified food labelling – at state, federal, and international levels. The battles often involved the use of citizen-initiated referenda. The policy conflicts have been policy-centric disputes – pitting organic farmers, consumers, and environmentalists against the food industry and biotechnology industry. Such battles have raised questions about consumer rights, public health, freedom of speech, and corporate rights. The disputes highlighted larger issues about lobbying, fund-raising, and political influence. The role of money in United States has been a prominent concern of Lawrence Lessig in his recent academic and policy work with the group, Rootstrikers. Part 1 considers the debate in California over Proposition 37. Part 2 explores other key state initiatives in respect of GM food labelling. Part 3 examines the Federal debate in the United States over GM food labelling. Part 4 explores whether regional trade agreements – such as the Trans-Pacific Partnership (TPP) and the Trans-Atlantic Trade and Investment Partnership (TTIP) – will impact upon

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Nutrition plays an important role in the development of all organisms and in particular that of farmed aquatic species where costs associated with feed can often exceed 60% of total production costs. Crustacean species in addition, have the added metabolic requirement for regular moulting to allow normal growth and this requires large amounts of energy in the form of sugars (glucose). The current study explored the capacity of the giant freshwater prawn to produce endogenous cellulose-degrading enzymes capable of extracting nutrients (simple sugars) from plant sources in formulated feeds used in the prawn aquaculture industry. We identified a putative cellulase cDNA fragment in the target organism of 1576 base pairs in length of non-microbial origin that after protein modelling exhibited a TM-score of 0.916 with a described cellulase reported from another crustacean species. The functional role of cellulase enzymes is to hydrolyse cellulose to glucose and the fragment identified in GFP was highly expressed in the hepatopancreas, the site of primary food digestion and absorption in crustaceans. Hepatopancreatic tissue from Macrobrachium rosenbergii also showed active digestion of cellulose to glucose following an endoglucanase assay. Cellulase gene(s) are present in the genomes of many invertebrate taxa and play an active role in the conversion of cellulose to available energy. Identification and characterization of endogenous cellulase gene(s) in giant freshwater prawn can assist development of the culture industry because the findings confirm that potentially greater levels of low-cost plant-material could be included in artificial formulated diets in the future without necessarily compromising individual growth performance. Ultimately, this development may contribute to more efficient, cost-effective production systems for freshwater prawn culture stocks that meet the animal's basic nutritional requirements and that also support good individual growth rates.

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The use of malathion in fruit fly protein bait sprays has raised serious concerns due to its adverse effects on non-target organisms. This has necessitated the evaluation of novel reduced-risk compounds. This study evaluated the effects of spinosad, fipronil, malathion and chlorpyrifos mixed with fruit fly protein bait (Mauri Pinnacle protein®) on attraction, feeding and mortality of the Queensland fruit fly, Bactrocera tryoni (Froggatt). The effects of outdoor weathering of these mixtures on fly mortality were also determined. In field-cage experiment, protein-starved flies showed the same level of attraction to baits containing spinosad, fipronil, malathion, chlorpyrifos and protein alone used as control. Female protein-starved flies were deterred from feeding on baits containing malathion and chlorpyrifos compared to baits containing spinosad, fipronil and protein alone. Baits containing malathion and chlorpyrifos caused higher fly mortality and rapid fly knock down than spinosad and fipronil. However, spinosad acted slowly and caused an increase in fly mortality over time, causing up to 90% fly mortality after 72-h. Baits containing malathion and chlorpyrifos, applied on citrus leaves and weathered outdoors, had longer residual effectiveness in killing flies than spinosad and fipronil. Residual effectiveness of the spinosad bait mixture waned significantly after 3 days of outdoor weathering. Results suggest that spinosad and fipronil can be potential alternatives for malathion in protein bait sprays.